-------
O 0
CUE
-H 18
- SJJJrH
rH rH tCfH CO
O
O> i)
O\ ej
\O rH rHrH
OO OO
ooooo
ddddd
VO
o
ooo
odd
O
c-
o
AJ
co) a
8*H 3 O AJ
•O »"H JJ 0
5B M
M H
-
0)
Q
§O
OOCOCOO
-cMoOrHOO«n
CM v v «n
oo
oo
OOOrHCNOOO
OOOrHOOOO
O\ 00<£ r- *
OO
V£>
IT) rH 00
OO COOOOOrHrHOOO O
oo ddsorHoddddd d
•o
Q)
oo
O
CM
60
M M
"35
01 M
OO
COCOOOOO-3-OO
VDVO\O ooiDi-t
CM V V
oo
do
O> rH
OOOCOroOOO
ooooooooooooooooo
OOOf-IOOOO
CO
•o
o
CO
M
S
UJ
to
0)
rH
3
rH >
CD a
u X
££
OrH AJ
AJ . fl) T3
V O B EC B
KKMHBtd coo)
oj a) )j ra B >, HP
gH«fl)«O-oo3Seo S33
P3M*O*D «-1^^p?(3666rHrH
S 00
O S3
BrHlH.rl
03 0) BrH
0)
CD
AJ
0)
0) O
B lJ
S R
0)
•O
O U
rH rH 0)
CU (d AJ
^^ CO
AJrH
a)
0)
OWrH
S C
Q)
"OJ
* • V «M CM •—^ ^^ ^— *»• B Ul S O
SrHrHrHAJCXil I Q)AJO>AJrH*rH
' - ' - 0) a CM .rl -rl (3 X! .0) O .rl
146
-------
o
t^.
o
•O &H
4)
3 S
' I
I g
CM
CM O
I 25
> I-l
0) 04
e
S
w
0) CO
t-l O Jrf
•rifl O.S
oj B«* id
j.-i
BOH «
CM
o
ooo
ooo
00
do
oo
00
oooo
dodo
o
d
JJ DO
i o B 1-1
co s «di-i a)
O O 4->f-< 4J
CM z e o «
oo*
•oo
wcoo
, ,-! , oo
to mir> oo
>ooc«joooo-
t-iu"i "">
cor-- CM r».
oootoooom oo
--- "
cMr-
0-40
O O O O O OOOO OO
o
Oi-l -U
O ffl
£
01 O B
SB a: h H a
a. D.3 <
JJ -
e e a o>
CO
•o
0)
•O
03
JJ
5
•o
0) "O
co B
eg co 01
0> co 3 ex S *
•LJ 01 M eg >. 3 8
" O 3 6 O i-l B 3
fl CO O -H »-l 3 -i
_ 0>i-4i-li'£Via S B i—I i-l B
i-i^ia,B6 ocor-i^o)>>ao
cxec3o)f-<3oj-)4jcou'oi-i
M«.«*j^!H*!g.5^«3g3
o
f-H 8>a>
X J2 N
o oi o e
-li-lttl«e OJ2
B H « o PI-H o Pri w JJ jj \? p«
•
s s: HOO
147
-------
o
t^
*^
1
I
4) to
vH U A!
M«rl CX.B
O\ JJ B-»4 «
O» C O Pr-l
r-«i-< tOHB
«5fi
OJ
oio- •©•&••
• » • •
oo oo
o
o
oooooooo
oooooooo
U 60
_i o d fc
22 c «•** o
O O 4J«-4 U
e o «
oooooooooooooo
OOOOOOOOOOOOOOOOOO
0) 0)
2
1
4J JS «
4J 4J 0) WO
ft) 0)r-<
r-li-( O. 0
0)
a 41 n
« B B
4J JB 0) 0)
AJ 4J O) 4J rl
- <
e6jc.eo.fiO os
i-i o
« OJ= QO O O D
VO ljf-40 I I I I
O 0.4J SB S I I B
O «Tl I I -*VO I
148
-------
o
f-
o
VO
o
Sv
a> 09
CuC
er> u o-H td
e^ ed cd Mi-!
r-ii-< OOH «
oo
ooo
ooo
JJ CO
I O 6 K
(O C <8-rl m ui i/i
O o OO O o
- —joooooooooooooooi
0) (1)
4J 4J
cd « o>
r-l rH ffl 4J 01
« td 4J « C3
JSJ3 «r-4 fl)
JJ 4J«-< >B< 6
JJ JJ rH Cd
3 Of-l >>N
pa O >>J3 6
I I 42 U fl>
i i 0) B '
, I i ,^ j ^ I ^g
Q Q O OrH
XJ 4.)
C C
0) (0 CD
C Vi Vi
w £
/-s O^"* 0) JJ
ed N Ji! B J3
^ B^ pa o <
149
-------
Ov JJ B*ri S)
Ov a a lirH
§
CO i-l
oo
oooo
ooooo
v
co
o
ooo
odd
o
r««
O
»
B 0) O)
O -r-l AJ AJ
C3 ^^ QJ 6J
to a o) a
V V V V V V
§ g
U g
c
!i
tM Q
> §
O Cu
g 1
u
•o .u e
01 B (U
~ c 2 a
o •*( y o *-*
oxir-i ±1 a
C4 BO-I 0)
OO
58
eon
oo >A to oo o r>» co
OCMI>vOOOr-_'*_/>_.
TJ
ei
o
C"t
vDcooooocsioooooooo
OOOOOOOOO
ddddddddd
o
eg
00
i-l U
(3 JJ
a) ei
B3:
CM
>!
oo
vO\O\OOOO>i-lOir>OOOOOt-lOOOO
£
g
W
o) o
S3 35 UH
O.G.3
cS
B a
to
•O
o
CO
•a
•a
B
CO 0)
l-i to
4J
0)
l-H >
a) «
•u x
,e. <=-d I
p B >j a ji j: o
01
1
a
01
•o
M
O
0)
01 O
•U Oh
o 01 o
o, H 27!
5 *^? *!!J *T. ITT "» 2" X /"
to O/ c t"' O O 0) W r™
60% 0>rjO>BMOI»-.^^
BPr-ieBt-IO)BT-Hr-(i-l4Ja.«
01 01
U U
« a
rH r-l 01
a a u
£f a
4J Ui-l
ra
0)
0)
... w
u o
B KI-I
o«!^
0) (U M
c ij o
0)
ra to
_
-i-H e J: ai 6 i-i
« O ^ pi,gi S H
150
-------
•O
I
o
r«.
O
S
g
4J
B
O <
CJ EH
£,
CM
CM U
I Z
> H
0) BH
| *
fe
3
en
0) CD
rH U JA
•rl-rl CUB
OX 4J B-rl «
ON S) <8 HrH
rH rH 60H «
0) Q)
O OflrH
ui is e.
MM
"§•0
6 01 0)
O *H 4J 4J
co iSS
4J
•o 4J .a
0* B 0>
O «rl 9 O 4J
©.CrH 4J B
CM s>w o)
8S rn
4J 60
O B rl
1 SliH 0>
CO C 4-1 rH 4J
O Pj C rj at
S*Jg*
01
B • fl)
CM "rl ? 4J
CM EJ p£ ai
o *
u
60
rH rH 0
O Ot 4.
CM , . 01 «
CDS
B
£
M
2
Cu
^
CO
^
at
O
CO
I
CO
I
CO
I
O
CO
S*
e
CO
ca
Q
CO
>•
01
a
^oHoc^oooooo^ooo
CM V V CO
OO VOrH CM
OOOOOOOCMOpOOOOOcoOOOO
(AOOcOOOOrHOOOOOOOOcOOOO©
CM V V CO
I-H rH
in CM o o o O-CM ooooOrHOooocOf-i
CM V V rH U"»CM
rH
ci ^y*' CT*'*A '' ^^ f ' '
CMOO\OOOOOrHOvt>OOOOOrHOOOO<
CM V V
So m m
OOCMOOOOOOOCMCMOOO
OOOOCOOOONrHOr^OOOOOrHOOOO
CM V V rH
O tn 4J
rH "O fi
.£* »rl O)
U rH rH
o at
O M rH >
Oi-H 4J <0 0)
o at "O 4J x
4J • 0) *O O Ol
0) O B ra B H K
K EC MH B « coot
(i. Cu 3 < 01 M 3 O. •>* 0)
4JM ^|0)r(CI9p% Be CO
Pgtl*rj»rj •*H^!COO'r*3"tH"fHV( BrH
B B 0) • O
01 0) O rH
4-1 B fc J3
o oi o u e
H NrH B (
fi J3 l-i 0) <
SB •> 0>OOBr
•rl -rl MrHCOlHOrHJ
BrH 01 O 01 M EH rl >>4
0)rH 0 •> B N O^^O^J
Q)J3«tH"*H^! Ol^rH^C OJ '
vO
o
o
o
tniri CM CM
CO OO rH O
CMOOOOOOO
oooooooo
V V
iri i—t \nin
§o oo
ooooooo
oooooooo
CM rH
o o
ooo
OO 0
oooooooo
>oooooooo
>oooooooo
0) 0)
4J 4J 01
a; at B
rHrH O) OI 01
CD at 4J rH B
£if a) >•> oi
4J 4JrH ^3 i-H
UrH 4J CO 4J
3MrH,C!Ci>Q>rl O>
) 0) >.Pi B IH O O
H ,£ 4J 0) .d rH IH
MfCICQ ^lOt B O BrH
j 4*J i *B Vi at as o *C
Ll 1 O> 4J O> 4J rH -rl
JCMM-rl BJ3 OlOtj
151
-------
•o
d)
!-• elf* n
-* a) —) a
O JJ
OOOOOOO
i-H O
CM
O .*
OOOOOOOVDCMOCMO
mvooodddddddd
•*-*
•O
0)
e >.
1-1 i-<
CM
o
o
OCOOO OO
o VOCN .3-
OOOOOOOCMCMOCMO
CMO
CM O O
0 _ O _ O
CM
no
mui oo
O
o
VO
OO
o> CO
03 C
eit-i-H M
CVrH 0)
o e a> a) *J
CM in u a) o
e) co o
"
o
r»
§
CO
o
CM
OCM
o o
vO FH O O
CMOOOOOOO
00
OOOOOOOO OO
o
o
OOO
odd
e
CO
CM <
i ^
z§
J3 2
H HI
H £
co
Iw
o
JM
5
CO
8
•a
01 B
c a «
•H U 0)
^3 O M
H a 4J
O 0
CM a jj jj
o 1-1 e to
CM jj 0) a
an
u>
c
Tl 0)
r* r-t 01
O J! H
CM 0 *r4
OtrtO
• • •
rHCM O\
OOOOOOOOOOOOOOOO
O O OO
ooooooooo
oooooooo<« I^COCM ooo
OI-HO VOCM o o di-< com d dd d
OO
OOO
4) 09
U CXW
O UT-( 0)
CO 3 O 4J
W
X
lOOOOOOOOOO
>odd odd
1H
O
OrH •
o a
M
S
«
MH
Cuo, D
4J«
Baatu
Ol-H
jz o
a
o-o
B n) co T-I Cl
< 0) CO p c D.
0) C a co
jj
0)
a a
o a)
i a
•HiH O, B
SSH1 O
p c D. - -
C a co X B H
cuwooeosnoEsa
i-i fi LI tn o •*> s -H -3
u 0.0 E c-S a B
C Oto
O tn.ti. HH«ooooi-HH3SScoHsityDSl
BrH MH vt
a 0) B rH
eojd a) i—i o >
B OrH a BrH
a ft o> ,c IH •!-< j-
•~ WH - " "^
152
-------
o
r^
S
•O
01 JB
9 O
B pi
i-l. Cb
I g
O «S
CO O
7 g
> £
5 I
1
S
•o
01 a
C 0) 81
•<-< 4J 01
45 BJ M
e a u
ooo
6©o
OOOOOO-*OrHf>».tU">OO©OOOOOOOOOOOOOOOOOO
w.
"S-OB
B 0) 0)
O -A U 9
O .O «r-<
"* o 2>w
OHM
8
in ooo
) rH rH ITIlfl O
> o o oo o
>ooooo oooooo ooo
r-H CM
•O 4J B
O) B 01
O B 0) B
OT) SOU
CM .O r-l JJ 0)
01
B M
H
cSS
iri o O O O "1 O O O O O O
U r-l
0«
OtOE
g
e s 01 •* •*•
1-lT-ia.EB
i-t •
.
D a>n)o
> e
CU 01
, c
4J 41
' •"
CM
' B
01
01 01
f~* G
>> 0)
(£4 r™!,
4-1 X
0) 1-4 01
MO O
ffr-f Vl
*J J3 01 O
C I-i 9 O
01 U r-l-rl
JS 0) O IJ
153
-------
•o
O O)
S >>4J
O 1-lrH B>
,
BO
o
Oi-ioooo m
CM «*
O CM O CM-*
OOOOOOOCMrHOCMO
l-l CM rH
O O wioo O O O-* ir>ul OO
CMOOOOOOOOOOOOOOOOOOOOO
i-l 00
COOOOOOOOOOOOO
-
•o
0) 0)
O 4J 5>%4J
M BrH CO
oo\oooo
IDVOVOOOO
rH CO
•£ 00
O CM VO I-H CO
OOOOOOOcorOrHCMO
oWdddddddddd
rHCM
CM i-l
O U1 i-t 0000 O
rH O O OO i-l I-H O
COOOOOOOOOOOOOOOOOOOOOO
o
r*.
S
£
eg
0)
CO
C
CArH OlrH «J
o B a> B 4J
u m ca
SS W C 3:
U C
CO <
lOOOCOOOCMr-IO
o
e
E
.
'§
f> o
CM S
< M
> J
O.
e a;
A
£
S
CC
C
•rl U
ft <0
es jj
Ct C
C*
•o
ey-o e
§-rI 5 3
J3 tdi-H
W «
OB M
O M H
CM
i-i o
>O O OO OO
o o o o o o o o o o o o o o
•C 60
0) C
CT< 0)
CO -rtr-l 4J
O U3^ CO
CM BUS)
UPu
VO
ro
UV O O
ooooooooo<
00
o
01 p B to u B
SS JB >J H B a (Ofl Q)
Cbd.3 .
B
0)
id a
'
a
w
5
0)
a
j3 01
•u B
oi a
a) ox:
a t-i 4J
0) O 0)
01
01 -O
C *r^
01 f-l
3 O
rH rH
O 01 J3
BO
MM CD
_ HB OB|B
33$-l'O*D *rl.TJl>IC£>Q*r(3*lH*'Hh C,-H»iH*iH«rf
8 B 0) iH ^1 ; B N
NrH O S O 0)
B 0) 01
aiHrH i-H 4J
rH a a a a
B.C.C.CI-I
01 u 4J u a
JJ
B TJ X >»rH ft<
HhMNOlOIOQJNX
o i a o i
BqrHat)BrH'0)BrHrH!kirH IJ34J 0,2 T
Sz!.o)IBrir|i-ix: oijSrH oi^vou o> a> CM
01
OI
4J
O) 0)
B O
0) M
IH O
Q -£,' a
I iJ Ij
0)
B
0)
I-H
I
Q) Q
BrH
.0! .0 _M
154
-------
O
VO
•D
I
v<
JJ
B
O
CO
CM
I
4)
rH
^>
I
o
5
E2
fe
I
IS
4) 4)
O JJ !».JJ
rH (SrH M
H
•O
41 0)
B >iJJ
O -rl t-< CO
CM SOS
O
B 00
co B
OJrHf-l rl
ON rH 0)1-1 4)
o B 4) B JJ
CM .rl JJ 0) «
« W B »
4J B
CO j ^3 C^ c? C5 CD CD CD ^5 co CD ^D ^D
\O VO COO
1— 1
CM CM r—
CM O moo CM
OmOOO OOVOOOO OO OOCMOOO
VO VD CM O O rH rH O F** CM O O O O O O O O O
r-
CM m ov r*i r**> oo
OOOAOOOOOCMOOOOOOOcMmO«3-co
voo'inddcMrHdeM^dddddddddd
rH rH rH tn
*
mvo
i*^ o\ . o co vo m -^ m
OO O.OO.O.rH^ CS1OO;O-OO-O O'rH r>COvOI»-OO
^5 C5 1^ ^5 CD C? '^^ ^5 ^— > C5 C? ^^ ^^ ^^ ^^ rH rH O^ ^^ CM
cMc>3ddd-*d'-!o-*odooo«*inrHoo
CO CMVO
M
O O> JJ
.-* r! *r! 0)
JD o a
O rl CO rH !>
UI-H jj a a a
o « o-o JJ x
fl) O B w OB H-'SB---
S3 pC IH B-I B a co'*rl fl)
JJ* rlfl)riatO>. SB tO
BSaO)0)O'OOt>03BOB33 4)
SSUtS'-O «rlJ3WCOO«rl3*rI*rlrl BrH
B S fl) «rl «H 08 }H CuO SB'HSSO) BO)
«rl.*rl Q4BS OCO rH»rl4)SOOO4B'O 00*Ai
BXEBBrH3OJJJJJJtO*OV/ v v v v
rH CM
m o m com coco o
rH O O CM O rH rH O
OOO OOOOOOOOOOOOOOOOOOO
B
a 0) *O arHrHrHJJ 0) O)
j;o) B -ri r-taaaa r-i B
JJB 4) M B,B*B.Br-4 >, 4)
'rH 4>a 3 O OlJJJJJJa JSi-l
O fl) 4) O fl) JJ 6 S fl) frl rH rH J3 SO JJ
H JJ Nr-l O B O 4) ST3 X >>r-lpH 4) 4) rl 4)
§fi »B 4)OOOJJBBr-4Hq-4a)4)aoxo)o>^ojJj3o)o
BrH (UOO4)rlHOh*rlrH>.JJJJJJrHlJJriaaUj2
*«i 25*Tj ri"£* m'r'^l m'r'vo'S'm rt*^ eM^«rl«S^-emo IH
155
-------
«*
>
9)
rH
J*
H
CO
1 1
S
e
i
u
2
S
i
o
i
i
co
o\
•a-
CM
O
rH
CM
^
O
CM
U1
O
CM
O
IN
CO
O
CM
1-4
O
CM
W
s
•1
0)
a.
05 CO 5
B a
0) to O
BJO e
o
o
60
B
-H 01
rH CO
^ B
cw
•c BO
0) B
EiH 01
•rl rH CO
*O ^d B
H O«rl
0*
•o
01 01
B OlrH
•H U O
,0. to B
H a o
osw
u
B B
6 01
•rl U g
4J Cd AJ
3 01 «
rH E 01
0 M
CO H
60
B
•rl 01
rH CD
v B
0-rl
S0*
•O
oi a
B 0) rH
•rl U a
,O H> B
B a aj
O ^C C/3
o
rH
>
C
rH
S)
Q
rH
Si
Q
rH
O
rH
^
S)
a
rH
a
1-4
ffi
O
00
u*l O fl ON CO
cM-3-o "xj-cooo OOOCMOVO move
CO VO OO rH rH
CO •*
rH
VO rHrH VOf**^*^
CO CO O rH CM O O O rH O CM O\ r^ CM O
CM CM O rHO OOOrHCSCMOOOrH
CO CO
„_ OO mco CMCO r^ €»•*
CO CO O O O <3" VO VO VD O O O CO O "1 O O rH ITi
CM *ij" f^t O O rH r-l CM fl ^ o O U"1 O CO CM O O O
CMVV rH ~^,v-.w.v-i-H04
C>) i^ ON O O ON ir"i O O O O
COCMO OCO OOOCOOCOrHCOCMCO
U1 CO
VO C-
00*H; CO rH CO ON t*- ^* VO
OOOOOIAI-. O OOrHOSOONCMO U1
o o o oo o CM dddeNdd
CO
O CO CO 4J
£ 33 S
0 rHrH rH
O O 0}
o°«S "" SS
u • a) "o > o 01
OlOBco BrH H S3
aSSChHSffl cooio
o.o>a§O3^>> EB ™ IS
8§01-rl'rlvi$|JOi BB-rtSEO) CdWBrH
•HIHO.BB ocorHrH^iosooa.B'D aoi o> i-i
5i5^2Sri52'y'y4joi'ciiibcL'onic!t>'~<<«
•rl CO 01 p% >>*H rH,COOBMCO.C.BOlHO!cO«rl01-£
SSSHOOOfaPuHE-i^^CJOOOrHMSCiSCOtH
00
*•!•
*
'
VO O
cod
ooo
CMOO
00
,
§00
o
CM
_ rH IT1 rHrH rH
ON O O -4" OOO
••••••••••••••••
V
vO
OO
VO O
09
1 , . .
1
o'oo
r»-OO
' Q)
i 0) U 01
, B 01 CO B
CO tJ rH 0) 01 0)
•B *rl Cd 4J 1—4 B
J-> IH .C « >> O)
rH 0) 0 CrH ^. rH
i CO 01 O rH -fl-cd- • 4J >,
4J B (H X! 0,^3 01 OJ .C
O O1O UO)rH4J BO U
H N*i§ BX£0)0)»H 01
*• 0)C)OBrH.C Ol-CrH Lj
co o) js «ri «« oi n) >M-H u u x; oi o
0>BNOl O4JJ3W4J42BM90
BrH01BrHrHrH4JCL
-------
ON
i—I
es
X «
O CO
a
OOOCN
dddd
O
O
00
do
O O O "I v£> r- O
OOOONOOOO
o i • "
ON 00
OCOO
• • •
Ot-lO
V
vl U 9
US Wfl
e oxw
O tH<*4
OH W
oo
O
ve
CM VO
OOOOOf-OOCMCM
-------
CO
«n
§
g
,a
II
AJ
II
g
43 CO
fl fe
oi m
SJ-rl-H O."5
O\ U Ox-l B
tH B «8>liH
t-l 60H CQ
££
OOO
odd
oo
do
o o oooo
do dddd
o
o
sr
StH'tO
o—i B
£0*
CO ON rH CO
ooo r-»m
ooooi^-
otoooo<—
m rHiniHtH ' r^
- -01 O«NOO m o eMn
cMno oooo co o oo
>oootnoooo<
m
o
m
o
CM i-H
i OO
§
CO B
BUB
t> »H C O
r-lr-4 -H
5f^ O.M
O C042
« 3
rH
1
n
CM
10
O
CM
O
in
O
in
0) B
_ O O.U
O t*«H 0)
CO SOU
f« O-r4 B
I
mm
oo
CMi-lOOO
CNI eo I-H i-i in
ooo >nr^
oooof)
t-l i-l CO tH tH '%£)
-
B B
U X
O 0)
0)
B
O)
o
I-
0)
B
ai
B
0) J3
C JJ
a) co a)
a) a)
BBB
0)0)BAJBB4JM
.QNJSOIBJSaJO
OBJJOXliJOiH
0) 0>
aiai
r-lr-l
158
-------
oo
in
O
vo
0> 09
O.C
4J C -rl 0>
« ffl Mr-l
r-l 60H «
O
d
o
d
oo oo
do do
o
d
00000000
dddddddd
•o
§
§•
P.
IS
9) fl)
CM i) xu
O ffl r-l W
•* CU-r-l (8
oooooooooooooo
ooooooooooooooooooooo
JD
CIS
C5
g
52
tn
o
oo e
C 4J W
VO -O-r) B O
o«-i
CJ O
"
00
OOOl
5
4J
•O JJ C
a) c o)
O B 0) S
O-H 3 O 4J
C§§<
s
a
a.
0) 01 C tt>
EB«8Btt>4)
co ax a c B
4J £ 0) 0)
BBC
o E e e
to « (B tO
0) O
C 0) B
(D (11 0) "-< C 0)
f-l
O
AJ B O to
4) 0) 6
>>« j: o
e x: B. 03
•H JJ O 4J
fl)
CuO 6
<1) ID
e E o
OO^
BMO
OOi-
,
r-l r-l 0) « 01 X!
osuearioo'OfiO'-iot-ieo. &.4J u m n> o <*
Urln-l4J4J B
c
i i
..... . _ _
' ' * ' H ' I I I I I ',CDt-iPOO4J4J4J
159
-------
0) to
•H O .M
0.C
C-H ooooc
«*
CM
I
JO
&
60 B
CUB
\D-O-H B O
OrHrH ftfH
C4 Qr-4 Q.M
U OWJ3
K 3
•O JJ B
OJ C 0]
§B o a
•n y o 4J
CMUir-t 4J a
B>H V
85
V V V
89
O ft.
Ot-l ,4
MOV
B a
SDK
c§
g
M
2
I
CM
CO
a
B 01
01 B
O)
0)
0)
^•S'-N
X W C
O O nt
-
« ^(
C M-l 0) X
e>Hn-i Br-i -o 8
• 1 i-HW g >, &,
ftnt-. 3r-ICO 43 Iff
• « to 9 ID
CM CD O to C 13 I.J M
O O 18 rH O O
0)
•H
rJ
ou
_ _ « «-* 1/S CNI CO-3-VO rH „,
i po I iMCScseMcMtMOjs
tdt tdtdrHrHrHrHrHrHrHft,
- - ~ 4J I I I I I I I (8 Ql
160
-------
00
o
vo
|
•a
§ §
c £
4J
B «tf
0 H
O <
^ Q
•* (S
CM Z
1 1-4
'"* g5
01 2
rH <
O3
H [n
S
Crf
E
g
CO
60
i-l 01
O^ ^i 03
O to B
CM (DiH
B f**t
£
T3 60
a> e
. B i-4 0)
r^ 1-i rH CO
0 J34 rH
O j£> co E
JrlcS
B
s
s.
Cu
CO
CM
•>,
03
Q
CM
^,
(0
Q
CM
cd
Q
CM
^
cd
O
CM
^
03
£^
CM
K.
cd
Q
CM
5»
cd
Q
CM
>
(C
0
C3> ^CO S rH
OCOOrHOOOC^rH-d-OOOOOOt-HOOO
vor^-cooomoocMoooooooooo
pH
00
o>oo mcM om-* r-if-
CMVDr-~OOCMrHrHCMOOO-*rHini-HOOO
CM rH
00
^ po O ^O O O OOO CO CO rH O O
CM 0
vO
CO
O\ m-«t O CM OOCMrH-*
CMinr~OOrHrHOVOOOOCOOOrHOOO
CM CM g rH
OO in r^- *^ CM
in i£> o O O CO O CM vO OOOOOOCMOOOC
vOv&CMOOCOrHOcMOOOOOOOOOOC
CO V V rH
CM
*H^ O\
O rH 4J 03 03
O 03 *O 4J X
jj . flj 73 O 0)
& O B 03 B H S
AJAWO)>-4n>> SB 03
|Bcd«IO)CJ>OO3CoB3i3 W
i-t*rlCXBB OOSrHi-ialBOOCXB'D 60Jl!
SSHOOObitwH^OOOOMJsa
in
i-HOQ
in
OOO
OOC5
*"^
CM m
OXOCMOOO c
COOOOOOC
CM OO
OOOO
rH
rH U > B N O '
rHC8S<-IO)S'-4rH
O
0
rH
CO
>ooe
>ooe
0
o
s
o
o
0
o
0)
01 B
B 0)
5 2
.C rH
oroet
'orm
troto
rHm iH
Si O B
U Pi-l
03 O C
XrH 1
!§ScM
O
o
t
m m
o o
>OfOOOOO
>Ocor~ oi
JJ 03 rH B
03 rH >> 0)
rH 03 ^3 rH
£ 4J 0) 0) ' ,C
4J .C BO 4J
jsE o> o) n o>
Cb B rl O O
rH 0) JSrH K
X£ 03 B O BrH
f u ij 03 cd oj j:
« B "S S JJrH^I
QS^£HHH
161
-------
CO
i
e
•H
XI
-a- o
CM SB
« w
JO
5
0)
03 CO U
(Oft C
fr) t| GO d
O 0) o £
*^ S* Ei I-
•ScSrS
•O
0) 0)
CM U >,4J
O CdrH tO
>» o~-i s)
U0»
H
at eo
B B
•H *fH 0)
rH rH B tO
O S) CO S
33*
rHT3 60
i-H OJ B
\D C3 4J«tH 0)
J£ S3
U M U ca
ai o>
C 0) r-l
r-< "-(.DO
o x> to a
co B ea eg
tSStw
0)
01 co cd
M B 4J
ON 0) O B
•* !> B 0
CM 0» W 0
050 B
O
U
co
e
_ -rl 0)
O rH to
rH J£ B
€^4 y ^^
a.
SAHPI£ POINT
CM
>
CO
O
CM
cd
CM
Is
Q
CM
«
O
CM
^
a
0
CM
a
o
CM
e)
Q
CM
^
Q
•
i
*^ CM
_ o> CM vooooN-a- o CM
Or^O rHOCJvvO r-4 O OO O VO 1/1 OOO OO O OOOO
<1* VO O\ O O VO rH O O OOOOOOOOOO rH O O
CM
VDIO ^ CO i— icOi— ItOrHrHirjr^fO
VOI-OOOCM rHrt OOOOOCMrtOOO " O O O O O O O O O O O O O O C
tnvo^oo^ dio dddddddddd ddddddddddddddde
' : '• • ;;
tr>ir> , ,_i PH ^f r~- r-i
O\ O\ O O O rH O\ T-4 CO OO OOOrHrH OOOO OrtO OOOO O OO rH
IO V V ^H ^"^ ^"^ TT^ ^'^
U^ ITl 00
OOir» i-i m to CM to r- m
OO >O O O O *O IO rH CO O O O PO O 00 f^ C^J O C*) ^"* O CM *"* f^
CMCOOOOO«Si-(T-tjav oooooi-JOOOOOO OOOOC5 OOOOO i-*OC> O O
CO
CNJ too voeooooooo^o Ot-i mcoa\ oo
C*") ^H Ov in ON e*"i
CM rH SS^rS'>,£i5rH?
'W a>I~loS>CNO'SoCl >»x! £ "H W >,S5
zzSc^ogfifififi^^iSScjI'^l^cSlsSllfiSl^JSaSI'risl'si
1-4 -^ i^" I— 1 oooooo
V
VO VO i-l rH
i-H rH O O
o ooooo
d ddddd
0)
0) B
fl) 4J m fl»
)iethyl Phthalat
Jimethyl Phthala
Anthracene
'henanthrene
!etrachloroethyl<
'oluene
?richloroethylem
162
-------
o
CM
t>0
.9*
r-l 01
U
U1V3OOOOOOOCMOOOOOOOOOO
CM
VOOO
does
o
o
o
•
o
•O 60
o> e
c-n o)
fv .rl r-4 to
O J04r-<
•rl JJ ft
,0 co B
B 0 0
OS to
in
00
vOOO
• * •
oooo
•o
s I
5 e
jj
I S
-a- o
V g
> id
O -Z
1 ^
* ft
«
CO
•* •* jj a
O 4J flj 4J
*0 rl
r-ti-4
OO
oo
do
O
d
O—IO
OO OOO
ddddd
60
CO
o
CM
CM OOO
CMOO
O O O r-t O in
OO
00
CM
O
CM
60
i—l 0)
0 JJ
Ist
COOO
o
d
o
d
o
CM
•a
a> ai
C 4)r-l
^i
S
CO
I
ooo
CMOO
O
d
o
•
o
b
o
£
o
o
OrH JJ
o eg
JJ • V
0) O
CO
•o
Ti
1—I
O
CO
"O.
•o
c
CO 0)
01 to a a-
M 0) rl CO
§
CO
•r-l 03 tt)
O B -• -
vf 9«rl>r4 _
c-ri E e o)
..^.^ -v
£^^^c5566,i!
c «> o
JJ 4J 4J
B « 03 03 01
(0 i-l rH r-l 9) JJ
CD <0 4J
C J3.C X
-------
s
••sl-
oi to
B fc
Q) CO 01
CJOftj
0) U
U >>U
OJr-( CO
e?
o
CJ* rH VO f-H
OVOOOOcoa>r- u->
OOOOO
ooooo
I/1IOCM rH rH
OOOOrH
oooooo
oddddd
V V
o
•C
0) 60
B B
•rlM 0)
1-4 B CO
^g-S
CO
\O r-4 i-l
O r-t O
O OO
o od
"1 rHi
O rHI-t O O O
O OOOOO
d odddd
60
f-t a) c
vo a 4J-H at
•sr^i etr-< u
fo AJ o jd a
u o
1-fO 60
CM a .S.5 01
OT< qJr-l 4J
CO u 01 A! a
S
CM
CMO
•
tv.<
CM
ns
at
2
CO
OB
CO
B?
Q
SCO
O
• • •
•-IOO
o
d
o
d
0)
ti to u
0) O B
> E 01
0) ra O
CSO B
O
U
co
BJ
Q
O\OO
COv£>cx)t—i
OO
o
r-t
CM
00
B
A! B
O-H
00-3-O
CM COO*
CO
VO
o oovo r^cM
OOOCOOOO\COOCO
voo
COO
CO
M
s
I
M
O
JS
U
O
O»-l U
O C8
O E CO
09 n
•0-0
o o
coco
U
01
rH
eg
rH >
0)
CO
J=
01 O
0,0
01 CO
« 0) O J3
JJ B rf AJ
O 01 O 01
H: NrH o S O
_ _ ' S £ rl lJ U
E a oi o o
93 CO 0) Ji-rlrH
rHiH«-l >JrHBOm3
OJBrH 0) O 0) lj H O
'JrfOirHO>ENoT<0bQ'
OrH ffl BrH OIBrHrH XrHI.
•rl^JS OJXirH 01
N CO CU po O rH S3
o ox;
•u B o
B 01 01 01
•rl JJ 4J 4J
CO rH rH rH 01 XJ
i-l CO CO CO iJ CO
B jC J5 43 to rH
0) 4-1 ,rH J3 C CD
01 O 01 N >-,&< E
SS2.4J
-------
00
m
O
so
•o
II
4J
B <:
§ i
u
2
•vf
CM
• I
>
0)
J3 CO
cd
H ft
CD CO
1-4 1H CuC!
ON 4J S i-l *
ON cd Cd t-l i-l
1-1 1-4 60H CO
O P
> 0
"O
0) 01
e 0)1-1
O *H 4J p*
CM JS CO B
CM s a «8
OS W
u
50
•5.C
ON rH 4J
i-i J£ cd
CM o pa
1-1
OH
•o
0) 01
O 4J >N*J
CM «i— 1 to
T-( us
H10*
0> Ml
B C
•J-1 •!-) (U
\O rH C EQ
o to to c
O i-i JJ cd cd
o cd "O u ><
CD.O a co B HE
£C3 !Ti W §™^ E 01 CO fl)
CuCX32!V4C^> EBiHEEQJ cdCD
"e">'l!co'o2Scxo'cd s'lj
•H Cd CD >. >fr< r-ljSOBVJCd^lJSOrJaiCd'r';
CO
m .3- m
VOrH CM T-l f^-
OO O . O PO
ooooo oo oo •
ooooo oo oo
V -
co mo o oo m o ooo
00000,000000000000000 ooo
V V
O CO O
OTHO
o
s
CM ao r~m ON mm
\o o o po r-i oo
CMOOOOOOOOOOOOOOOOOOOOOOP
CMOOOOOOOOOOOOOOOOOOOOOOO
V V V
o
r-4 V V V
cMr-400 PO cMmcMoo m 1-11-4 co
h»ooo o ooi^-ff o mm o
3OVDO-*OOO OO OO OOOOO OOOOOOO
•^ V V V.
m
ONOO
r~-oo
^H
B 01 01 0) 0)
0) 1-1 4J 4J AJ 4J 0>
B 0) B « « rt OJ 0) B
cd a) T> cdi-4i-iT-ii-ia)4u CD a>
j30) B 1-1 r-icdcdcdcd*jcd 1-4 B
4J B 0) V-t B JO* £* *£- ^2 cd i— 4 ^ Q)
1— 1 CDCd 3 O 0) 4J JJ 4J 4J i— 1 Cd JC T-^
cd w o x: TH rH i^ijsjSJS'S^ AJ ^>
JJ B^J-1 OCU.B CXCU CUPn P-i JS 4J 0) 0) < «C
O CDOO) JJBUO)iHr-4r-4 4J JS CO U
H Ni-IOBOO) B-DX >%r-4 i-l JS P* CD 0) U 0)
B£hh^NO)cuoa)(o x^cb B i-i o o
BE " CDCJOOAJCBl— ICQJ3B4J4J l-40).£l-4 t)
33 CO 0) rO i-l i— 1 tM*HO}QJcdOr>%0)dOr«H^irJUtCQJO
^•^ ^i— !CO^lj3OC^i-4»CI-l43^PQCD >>*C cd B O B i— 1
CJ r—t 0} O 0) M H O M i-l r— 1 ^> AJ 4J JJ r-^ f 1 J^ U V Cd Cd Q) •£•
0) r-4 CJ&BNO' CdOQ ^*J* «d iH W ^^ 2UJcD4-BV)?O
1-4CH C ri 01 Bl- Xi-U OuZ ' 4J « 1 0)SJ->OIUr-li-<
fli .C *r4 *»^ jC 0) >£ '""I QJ .C ^0 W fl) QJ ' P^ <3 "p4 »H *»~^ »r^ C! <£ QJ O ti
165
-------
CO
10
CM
ta a
(A u
OOOO
POO
oo
o
m
oo
CM
vo
PO
OOOs
ooio
ovo r^oo co
VO CM PO
CM
IO
CN
0 Q)
OS 4J
ooo
CM
OOOOVOVO
O 00
• OO CMVD
o • • • • . , . . .
^.- JOOOOrH OO-
• OOCM 1O
o
vOvO
O f»- PO CO OO
VOPO
1OVO
I
m
21
o
CM
« 0)
OS U
OOCMO
rHO
o
- o
VO
o o o o m
§">O OO
C
CM
CMCMOOtO
00
* 3
OOrHO OOOOO OOOO CM OO
OlOOOO ••» O vo O O
Of- CM
COOO
00
CMCM CM V
to
rH
CM
•O
0) Q)
C fl) r-l
*r4 U Q
J5 ra ff
9 a w
OS=w
CO
B
OJ
o
CM
CMCM
g
M
S
K>
a>
BtJ
O-rl
0°
,J O
q) CO
•o
O O-D
S3 33 U to BO)
CX O* 9 0) CO B CX
JJ (4 0) CO tQ
m a
.CO) B i-l
•u B ' 0) b
«) a) 3 o
0) O f rH rH
B M 4J. o OJ.C
OOO) JJ C O \u -n r-f rH OJ
NrHOBOtt) CTJX >,rHrHj;i
B^!Vlr4UNO)a)OO)NX XCU
0) O O.O 4J C BrH COX! B 4J U r
c o> o) a) at
•rj 4J 4J U U
B cd ccJ c[j m
rH CD cd W « U '
C J3 J3 J3 J3 edr
01 4J 4J 4J tlrH
£,&£,£.jz eg.
0) 0)
c o
-..-c'seS 3'5'BS S§8
OrHrH«H Q) O O O4C*t7 6>0«M 0) I—I CJ > ta O •
5"*JtJOJiJiJCUpM C? O rH Cd B rH B rH rH
_innnt.-.«-...._. -airJ^^ialj-rHu,
~ 10 CO (0 OrH -S
oo
X r-l I
B O
« «
.
) co i CM
-------
4J tO
O B
r-i i cd i-<
.-I C •U i-l
CM o c o
s o o:»
00
O OenOO O
in vo r-oo o
00 E:
C 4J Cd
O T3i-< B O
i-l r-l f< 41 -rl
CS Qr-t &, M
O O CO ,fi
00
o
o
o
u-1
en
oo
OOOOOO
O-*
OO OO i-l «-H en tri O
1-400
CM
CM
CM
i-l 0)
cd w
u-i
O 1-1
u-i VJB O O O O en
i/i i/i m O O en O i-*
• •o
0)
e
•
.QMS
B
o
CM B cd cd
OSto
OOO
CM \Oi-l
CM
CM
CM
60
C
•rl ^
•-< 41
C8 4J
uiui
Sen
CM
OOO
O
CM
•G
4) 4)
B 4)i-l
i-l 4J g
ft to S
S cd cd
OSCO
CM en CM
CM
00
oen
-*o
en
OOOI>>
ey>
41 41 41
., . 4J 4J 4J
41 S cd cd cd 41
i-i cd cd
p B f J5^_.
O 41 4J 4J JJ Cd
.£ <
H
g
0,
CO
4)
41
41
B
4)
4J >>
4) 41 A
BO -U
41 41 P 4)
-- , . B (J O O
_ „ . B4Ji-l4)X!i-l H
(DCU«O^Q)O>->OtJJ2Q)O
-- — -— — ^ — (jBr-^
_ .. -. Cd 41 JC
„ . 4)4=SI-i30
„ I U I S U 41 4Jr-l i-l
l-NS^-ri e.,e ai o^
167
-------
•O JJ
0) *O B
B 0) 0)
•n jj 3
43 <3rH
B «<4H
O U*W
OH W
if} ir, o
o o o
o oo oooo
d do dddd
jj
l!
ag
3ti
a o
u-i
W
js a>
Opj
•3-eo
en co
invo
O
v
O
O\ ON O
oo oooo
do dddd
GJ
O
oo ooon
oocoo
CM
oo oooo
CO CO
CM CM
o
sr
0)
O M
MrH 0)
ooo
OUtCOOOOcOM
vovocMoodod
M
O
CO
B'O
OfH
2
o
o°-3u
KBrill
Cud. 3 <
o) co
(-1 O
o w
•D
O 13
-rl e
ra B a;
3 OS Cu
JJ
01
rH >
CD (8
(d
JJ
5
u
C
a
43 01
4J B
0) ffl
01 O43
a M JJ
01 O 01
tO f-H O
0)
B 0) II) 0) 0)
•rl JJ JJ JJ JJ
0) S « « ed c8 01
•O KtrHrHrHrHCUJJ
rH
JJ B D 01 ^ r-Tr^T JJ 43
O 01 .. B -0 X !>»rH rH 43 (rl 0)
(SrH
0) JJ 4J JJ 4J i-f ffl
B43.fi»J>JN010iOdJ N'>,'^E
0)
01
rH
I
01 01
B O
01 W
0)
0)
rH
£
168
-------
•o
0)
B
ft
U
1
s^
in
0)
1-4
a
i
§
u
z
H
J
PM
i'
SH
in
I-l
CM
S
CM
•o
ID e
B 0) CO
•f"t AJ Q)
43 CO M
5 **
U
60
5.
i—* CO
23
CM
I
CM
*
©©CO ©©©©CM
IAI*^** ©ino©o
CO OOCM
oom
I-HCM
• CO
r-iOOOOi~iOOOOOO
CO CO I~»VO
l-<
CO
in oovoco f* co
or-
CM
CM
OO©
©OOCMVO
CM.
OOOOVOVO
r^.i»-o© ©»©©!-<
^•O moo i-«
\o coin
00 CO-*
CM vo
I».CO
^-
OO
©0©©©©©©^©©©°©
OO rH
tM
CM
I
© ©r»©
o\ c\ so ©
CO©
o
o
!-<
00 rH
OO-*i-l©
§OOO©
VO
covO.
1-4
O^ i-*-*
©CM O-*CM
1-4 00
i-l i-l
o©
e CD o o CD
^-1 4J 4J 4J 4J
S 0) « W «
-------
I?
o
OO
• •
in in
OOOOCM
O\ OOOOCM
O r-» O O CM i-H O
333
P p p f> CJ\
COO
O.CJS OO
o
I-.
CM
••
OOOOO Or-HOOi-lCMO
U1\D SO
00-*
CM
CM
to
0) E
I I
CM
CM
60
f-4 0)
Si JJ
OOOOOOOOQO
* (3
61 E
60
OOOO1OOOOO»HOOOCMCOO
CO
o
CM
to
I-) fl)
r-l CO
X C
PW
CM
I
CM mo
CM
V V V V
O
Ol-H U
o B
U . fl)
0) O C 01
S3 ffi MH B «
(X 0.3 < QI
a B a a)
3 E
e m
-»r! CKis e o
e x a ca 8)1-1
e o
Oi-l
M O
eg co
o
•O
i-l *C
01 B 0)
900.
M 60 co
0)
i-l
I
eg
"O O H 3 B
•rl SlOU) Q
CO i-l i-l >r4
O 3
01
CO
0)
U B<-<
Oi eg 01 d)
a. B •o toj B
a.oe a>
i-l 4J 4J 4J
E eg eg eg
eg i—I r-f r-4 Ot
i-i eg eg eo 4J
01 4J u u i-<
eg
01
B
01
MiJEJSNCOQHeOOi-*
0) 1-1 iH rH U
BJ=WU N B'D^ ^7' -13 W
» 0>CJOO.L)BBi-
eooi^>>Hi-''Wi-40ia)ego>>oi
iJi-i B O^J3 O CJZr-if UJ2£>
O(llUHO)-li-li-IX4J4JJJr-l _„
"'NO' eg o a >*f £ -H W S>,S u J3
Ct—ii—i >»J
o
I OrH O
i O >>cfl
c ' JS ti
•UJB
B O
eg eg
B M
jd
4J
01
o
k
-------
00
o
CM
0)
4J
CO 0)
CO
CO
6*
CM
cd
O
r*. t*» o
• • •
VOVOO
CM
1O1O O
oo o
O OOOOOO
O OOOOOO
v v I-H v
O
CM
moo r~eMm«3; oo
O.CM cooOOOOOrHrHOCOO
dddrHinooooooooo
oo
OOOOOO
• •••••
OOOOOO
•O 4J
wo e
B CD 0)
O tH U 3
C5 .O (C f^
•& e o)
rH M 0 3
M-IWH tH"O
w-i .So)
W O D^
CM
a
GO CO
inOvOOOOcovO
p o a o
-* rH JJ O 3
CM IM rt ti
B .CO)
ON
rH
CO
a) o W 0 -rl
m-* m
CM in oo
OO
oooo
in 060^
t»-
ooooo
mo
CO
ID VOOO O
ON 00
«o o
o
o
OOOOOO
ddddoo
tno
00 CO OO
O i-t iH OO O
ddddod
ON
rH
CM
4J
0)*rl 0)
3 O g
M-l O*H
B •<-> Jd
M CO
CM
CO
Q
OO OOO-*
mcM OOOO
CO
r-
CM
O OOOO
r-~ CMO o o
co-o-
rH rH
vooomoo
VO rH rH CM O
rHOCMOO
o
o
o
mtn o
ooo ooooo
• •••••
OOOOOO
0)
o>-i
rH 3 0) JJ
OS* «
\OvOi-lOOOOO<-l
g
I
PH
CO
171
-------
0
01
ss-a
m a
s> w
OOvO
cot
• oo
o
CM
O
o\
ooo
oo
00
o
O
O
CMtM o
CM
O
CM
to
Jd C
O-rJ
CO
csooooo o oooooo
£0 ooo'oo'd ddddod d dddddd
CM
oooo
r-.i-.coo
coo
o
o
00
CM
VO
OO«A
VD CM
\o
OCM
• •
OO
CM
CM
O O
O O
ooooo
ddddd
V V
S) g)
CO
£
O OOOO
•*r>.O
CO 1-1
o
•
o
in
CM
o-
ooo
oo
-a- i-<
OOO U1OCOOO
•» ooo or- oo
^O OOOOO OOOOOCNOOOrtOOOOOO
vod ddddd dddinddddd dd-Jr-Iddd
CM CM CM v i-< v
2
g
5
CO
0°
r-l
U O
a u
o
•o
o -o
•rl B
B c a)
CO w C(] Qu
01 M 60 CO I
4J
CD
i-l
I
S B
a. c-o
4) BiH S
W
UrH CO Cf-l
w '
co :
£ 0)
cu «
a> ox:
B M XJ
a> o a)
Nr-l O S
01 u o
i o
C Q) 0) 0) h
Vl O
cd B O
01
B
0)
4J
01
2
172
-------
4J
00 B
BUS)
O-Oi-l B O
rH rH i-H a> -iH
CM O rH O, (H
u OKI .n
erf 3
•J
CO
>1
td
Q
OOvo
in m m
CM
O
O
CO
O
in
cr>
rH
VO
ooo
CM
CM
5u
rH 4)
CS AJ
0) CO
B S
ooooooooooo
oooooo
VO
o-
\o
m
o
CM
0)
•o
a)
e
IH u &
js co a
E cd «
OSco
CM tJIVO
•o
I
c
1-1
u
§
V.
IS
vO
CM
CM
in o
CM Z
• H
> J
P-I
o
!H
OS
r-< a)
(0 4J
£03
C
^ C
0-rl
co
o*
OOO O
CO
O
CM
C5C5
OO OO OO
o
CM
•o
Q) a>
C a) rH
•rl U ft
iS§
o » en
o
oooo
v v
S
Cu
CO
173
-------
4> K
<-« O JiJ
•dxrl &.E
o> a B Ur-<
CO
,
oooooo
V V V
•u E O
c g *H
a» e—< u
c> g o H o
-*r-i M o g
COU-HM Jj-o
IM JT ffl
w o pi
CMOO COO\ OOOOO VOCMCOin OO
••• •• ••••••••• ,,
cMcot^ OCM oo r^o oo 1-100 CM oo
•-* BNOI eoo
r-iaaa«u«. r-<
.Cl BO >
K 01 5 ti 0)
C S 0 0
a B o B .
174
-------
§oooo
Oomo
ON
COON
CMOO rH
O-vO
ON ON
vO irt i-l
eo<-i
ON CO
§
in
o
aj
e
•O
o
OOON
OOO-
1-1 CO
CM
I
•8
H
1-1
CO
1-1
(J
0)
4J
I
co
(0
o>
u
M
§,
CO
i-l
es
«l
•O
O
£
o
3
o
u
g,
u
o-
VD
O
VD
ooo-
ITli-l
i>-
O-
CM
-*oo
I--CM
ooooooooo-*
1^^f> O r*
oo 1-1
c
9
OOv&O O
oo
-------
-------
SECTION VI
SELECTION OF POLLUTANT PARAMETERS
The Agency has studied copper forming wastewaters to determine
the presence or absence of toxic, conventional and selected non-
conventional pollutants. The toxic pollutants and nonconven-
tional pollutants are subject to BAT effluent limitations and new
source and pretreatment standards. Conventional pollutants are
considered in establishing BPT, BCT, and NSPS.
One hundred and twenty-nine toxic pollutants (known as the 129
priority pollutants) were studied pursuant to the requirements of
the Clean Water Act of 1977 (CWA). These pollutant parameters,
which are listed in Table V-l (p.79 ), are members of the 65
pollutants and classes of toxic pollutants referred to as Table 1
in Section 307(a)(1) of the CWA.
From the original list of 129 pollutants, three pollutants have
been deleted in two separate amendments to 40 CFR Subchapter N,
Part 401. Dichlorodifluoromethane and trichlorofluoromethane
were deleted first (46 FR 2266, January 8, 1981) followed by the
deletion of bis-(chloromethyl) ether (46 FR 10723, February 4,
1981). The Agency has concluded that deleting these compounds
will not compromise adequate control over their discharge into
the aquatic environment and that no adverse effects on the
aquatic environment or on human health will occur as a result of
deleting them from the list of toxic pollutants.
Past studies by EPA and others have identified many nontoxic pol-
lutant parameters useful in characterizing industrial^wastewaters
and in evaluating treatment process removal efficiencies. Cer-
tain of these and other parameters may also be selected as
reliable indicators of the presence of specific toxic pollutants.
For these reasons, a number of nontoxic pollutants were also
studied for the Copper Forming Category.
Congress has defined the criteria for the selection of conven-
tional pollutants (43 FR 32857 January 11, 1980). These criteria
are:
1. Generally those pollutants that are naturally occurring,
biodegradable; oxygen-demanding materials, and solids that have
characteristics similar to naturally occurring, biodegradable
substances; or,
2. Include those clases of pollutants that traditionally have,
been the primary focus of wastewater control.
177
-------
The conventional pollutants considered (total suspended solids
oil and grease, and pH) traditionally have been studied to
characterize industrial wastewaters. These parameters are
especially useful in evaluating the effectiveness of wastewater
treatment processes.
Several nonconventional pollutants were considered. These
included phenols (total), fluorides, phosphorus, iron, manganese
and total organic carbon (TOG). None of these pollutants were
selected for regulation in establishing effluent limitations
guidelines for the Copper Forming Category.
RATIONALE FOR SELECTION OF POLLUTANT PARAMETERS
The Settlement Agreement in Natural Resources Defense Council,
Inc- vs. Train, 8 ERG 2120 (D.D.C. 1976), modified 12ERG 1833
(D.D.C. 1979), which precedes the CVA, provides for the exclusion
of particular pollutants, categories, and subcategories.
Pollutants that were never detected, and that were never found
above their analytical quantification level, were eliminated from
consideration. The analytical quantification level for a pollu-
tant is the minimum concentration at which that pollutant can be
reliably measured. For the toxic pollutants in this study, the
analytical quantification levels are: 0.005 mg/1 for pesticides,
PCB s, chromium, and nickel; 0.010 mg/1 for the remaining toxic
organic pollutants and cyanide, arsenic, beryllium, and sele-
nium; 10 million fibers per liter (10 MFL) for asbestos; 0.020
mg/1 for lead and silver; 0.009 mg/1 for copper; 0.002 mg/1 for
cadmium; and 0.0001 mg/1 for mercury.
The pesticide TCDD (2,3,7,8-tetrachloridibenzo-p-dioxin) was not
analyzed for because a standard sample was unavailable to the
analytical laboratories. Samples collected by the Agency's con-
tractor were not analyzed for asbestos. Data on asbestos content
are available for a very small number of samples relevant to this
study as a result of the first phase of a screening program for
asbestos in a wide range of industrial categories. Of these
samples, only a few appear to contain asbestos at analytically
significant levels.
Pollutants which were detected below levels considered achievable
by specific available treatment methods were also eliminated from
further consideration. For the toxic metals, the chemical pre-
cipitation, sedimentation, and filtration technology treatability
values, which are presented in Section VII were used. For the
toxic organic pollutants detected above their analytical quanti-
fication level, treatability levels for activated carbon tech-
nology were used. These treatability values represent the most
178
-------
stringent treatment options considered for pollutant removal.
This allows for the most conservative pollutant exclusion based
on pollutants detected below treatable levels.
DESCRIPTION OF POLLUTANT PARAMETERS
The following discussion addresses the pollutant parameters
detected above their analytical quantification level in any
sample of copper forming wastewater. The description of each
pollutant provides the following information: the source of the
pollutant; whether it is a naturally occuring element, processed
metal, or mamifactured compound; general physical properties and
the form of the pollutant; toxic effects of the pollutant in
humans and other animals; and behavior of the pollutant in a POTW
at concentrations that might be expected from industrial
discharges.
Benzene (4). Benzene (CgHg) is a clear, colorless liquid
obtained~mainly from petroleum feedstocks by several different
processes. Some is recovered from light oil obtained from coal
carbonization gases. It boils at 80 G and has a vapor pressure
of 100 mm Hg at 26°C. It is slightly soluble in water (1.8 g/1
at 25°C) and it dissolves in hydrocarbon solvents. Annual U.S.
production is three to four million tons.
Most of the benzene used in the U.S. goes into chemical manufac-
ture. About half of that is converted to ethylbenzene which is
used to make styrene. Some benzene is used in motor fuels.
Benzene is harmful to human health according to numerous pub-
lished studies. Most studies relate effects of inhaled benzene
vapors. These effects include nausea, loss of muscle coordina-
tion, and excitement, followed by depression and coma. Death is
usually the result of respiratory or cardiac failure. Two spe-
cific blood disorders are related to benzene exposure. One of
"these, acute myelogenous leukemia, represents a carcinogenic
effect of benzene. However, most human exposure data is based on
exposure in occupational settings and benzene carcinogenisis is
not considered to be firmly established.
Oral administration of benzene to laboratory animals produced
leukopenia, a reduction in number of leukocytes in the blood.
Subcutaneous injection of benzene-oil solutions has produced sug-
gestive, but not conclusive, evidence of benzene carcinogenisis.
Benzene demonstrated teratogenic effects in laboratory animals,
and mutagenic effects in humans and other animals.
For maximum protection of human health from the potential carcin-
ogenic effects of exposure to benzene through ingestion of water
179
-------
E
and contaminated aquatic organisms, the ambient water concentra-
tion is zero. Concentrations of benzene estimated to result in
additional lifetime cancer risk at levels of 10~7, 10"", and
10~5 are 0.00015 mg/1, 0.0015 mg/1, and 0.015 mg/1,
respectively. !
Some studies have been reported regarding the behavior of benzene
in a POTW. Biochemical oxidation of benzene under laboratory
conditions, at concentrations of 3 to 10 mg/1, produced 24, 27,
24, and 20 percent degradation in 5, 10, 15, and 20 days, respec-
tively, using unacclimated seed cultures in fresh water. Degra-
dation of 58, 67, 76, and 80 percent was produced in the same
time periods using acclimated seed cultures. Other studies pro-
duced similar results. Based on these data and general conclu-
sions relating molecular structure to biochemical oxidation, it
is expected that biological treatment in a POTW will remove ben-
zene readily from the water. Other reports indicate that most
benzene entering a POTW is removed to the sludge and that influ-
ent ^concentrations of 1 g/1 inhibit sludge digestion. There is
no information about possible effects of benzene on crops grown
in soils amended with sludge containing benzene.
Carbon Tetrachloride (6). Carbon tetrachloride (CCl^.), also
called tetrachloromethane, is a colorless liquid produced primar-
ily by the chlorination of hydrocarbons - particularly methane.
Carbon tetrachloride boils at 77°C and has a vapor pressure of 90
mmoHg at 20 C. It is slightly soluble in water (0.8 gm/1 at
25 C; and soluble in many organic solvents. Approximately
one-third of a million tons is produced annually in the U.S.
i
Carbon tetrachloride, which was displaced by perchloroethylene as
a dry cleaning agent in the 1930's, is used principally as an
intermediate for production of chlorofluoromethanes for refriger-
ants, aerosols, and blowing agents. It is also used as a grain
fumigant.
Carbon tetrachloride produces a variety of toxic effects in
humans. Ingestion of relatively large quantities - greater than
five grams - has frequently proved fatal. Symptoms are burning
sensation in the mouth, esophagus, and stomach, followed by
abdominal pains, nausea, diarrhea, dizziness, abnormal pulse, and
coma. When death does not occur immediately, liver and kidney
damage are usually found. Symptoms of chronic poisoning are not
as well defined. General fatigue, headache, and anxiety have
been observed, accompanied by digestive tract and kidney dis-
comfort or pain.
Data concerning teratogenicity and mutagenicity of carbon tetra-
chloride are scarce and inconclusive. However, carbon tetrachlo-
ride has been demonstrated to be carcinogenic in laboratory
animals. The liver was the target organ.
180
-------
For maximum protection of human health from the potential carcin-
ogenic effects of exposure to carbon tetrachloride through inges-
tion of water and contaminated aquatic organisms, the ambient
water concentration of zero. Concentrations of carbon tetrachlo-
ride estimated to result in additional lifetime cancer risk at
risk levels of 10'7, 10'6, and 10'5 are 0.000026 mg/1,
0.00026 mg/lj, and 0.0026 mg/1, respectively.
Data on the behavior of carbon tetrachloride in a POTW are not
available. Many of the toxic organic pollutants have been inves-
tigated, at least in laboratory-scale studies, at concentrations
higher than those expected to be found in most municipal waste-
waters. General observations have been developed relating
molecular structure to ease of degradation for all of the toxic
organic pollxitants. The conclusion reached by study of the
limited data is that biological treatment produces a moderate
degree of removal of carbon tetrachloride in a POTW. No informa-
tion was found regarding the possible interference of carbon
tetrachloride with treatment processes. Based on the water
solubility of carbon tetrachloride, and the vapor pressure of
this compound, it is expected that some of the undegraded carbon
tetrachloride will pass through to the POTW effluent and some
will be volatilized in aerobic processes .
Chlorobenzene (7). Chlorobenzene
~
. also called mono -
chlorobenzene Ts~a clear, colorless, liquid manufactured by the
liquid phase chlorination of benzene over a catalyst. o It boils
at 132°C and has a vapor pressure of 12.5 mm Hg at 25 C. It is
almost insoluble in water (0.5 g/1 at 30 C) , but dissolves in
hydrocarbon solvents. U.S. annual production is near 150,000
tons .
Principal uses of chlorobenzene are as a solvent and as an inter-
mediate for dyes and pesticides. Formerly it was used as an
intermediate for DDT production, but elimination of production of
that compound reduced annual U.S. production requirements for
chlorobenzene by half.
Data on the threat to human health posed by chlorobenzene are
limited in number. Laboratory animals, administered large doses
of chlorobenzene subcutaneously, died as a result of central
nervous system depression. At slightly lower dose rates, animals
died of liver or kidney damage. Metabolic disturbances occurred
also. At even lower dose rates of orally administered chloroben-
zene similar effects were observed, but some animals survived
longer than at higher dose rates. No studies have been reported
regarding evaluation of the teratogenic, mutagenic, or carcino-
genic potential of chlorobenzene.
181
-------
For the prevention of adverse effects due to the organoleptic
properties of chlorobenzene in water the recommended criterion is
0.020 mg/1.
Only limited data are available on which to base cone ITIS ions
about the behavior of chlorobenzene in a POTW. Laboratory
studies of the biochemical oxidation of chlorobenzene have been
carried out at concentrations greater than those expected to
normally be present in POTW influent. Results showed the extent
of degradation to be 25, 28, and 44 percent after 5, 10, and 20
days, respectively. In another, similar study using a phenol-
adapted culture 4 percent degradation was observed after 3 hours
with a solution containing 80 mg/1. On the basis of these
results and general conclusions about the relationship of molec-
ular structure to biochemical oxidation, it is concluded that
chlorobenzene remaining intact is expected to volatilize from the
POTW in aeration processes. The estimated half-life of chloro-
benzene in water based on water solubility, vapor pressure and
molecular weight is 5.8 hours.
i
1,1,1-Trichloroethane (11). 1,1,1-Trichloroethane is one of the
two possible trichlorethanes. It is manufactured by hydrochlori-
nating vinyl chloride to 1,1-dichloroethane which is then chlori-
nated to the desired product. 1,1,1-Trichlproethane is a liquid
at room temperature with a vapor pressure of 96 mm Hg at 20°C and
a boiling point of 74°C. Its formula is CCl^CR^. It is
slightly soluble in water (0.48 g/1) and is very soluble in
organic solvents. U.S. annual production is greater than one-
third of a million tons.
1,1,1-Trichloroethane is used as an industrial solvent and
degreasing agent.
Most human toxicity data for 1,1,1-trichloroethane relates to
inhalation and dermal exposure routes. Limited data are avail-
able for determining toxicity of ingested 1,1,1-trichloroethane,
and those data are all for the compound itself, not solutions in
water. No data are available regarding its toxicity to fish and
aquatic organisms. For the protection of human health from the
toxic properties of 1,1,1-trichloroethane ingested through the
comsumption of water and fish, the ambient water criterion is
15.7 mg/1. The criterion of based on bioassays for possible
carcinogenicity. :
No detailed study of 1,1,1-trichloroethane behavior in a POTW is
available. However, it has been demonstrated that none of the
toxic organic pollutants of this type can be broken down by bio-
logical treatment processes as readily as fatty acids, carbohy-
drates , or proteins.
182
-------
Biochemical oxidation of many of the toxic organic pollutants has
been investigated, at least in laboratory scale studies, at con-
centrations higher than commonly expected in municipal waste-
water. General observations relating molecular structure to ease
of degradation have been developed for all of these pollutants.
The conclusion reached by study of the limited data is that^
biological treatment produces a moderate degree of degradation of
1 1 1-trichloroethane. No evidence is available for drawing con-
clusions about: its possible toxic or inhibitory effect on POTW
operation. However, for degradation to occur, a fairly constant
input of the compound would be necessary.
Its water soltibility would allow 1,1,1-trichloroethane, present
in the influent and not biodegradable, to pass through a POTW
into the effluent. One factor which has received some attention,
but no detailed study, is the volatilization of the lower molecu-
lar weight organics from a POTW. If 1,1,1-trichloroethane is not
biodegraded, it will volatilize during aeration processes in the
POTW.
Chloroform (23). Chloroform also called trichloromethane, is a
colorless liquid manufactured commercially by chlorination of
methane. Careful control of conditions maximizes chloroform pro-
duction, but other products must be separated. Chloroform boils
at 61°C and has a vapor pressure of 200 mm Hg at 25 C. It is
slightly soluble in water (8.22 g/1 at 20 C) and readily soluble
in organic solvents.
Chloroform is used as a solvent and to manufacture refrigerants,
Pharmaceuticals, plastics, and anesthetics. It is seldom used as
an anesthetic.
Toxic effects of chloroform on humans include central nervous
system depression, gastrointestinal irritation, liver and kidney
damage and possible cardiac sensitization to adrenalin. Carcino-
genicity has been demonstrated for chloroform on laboratory
animals.
For the maximum protection of human health from the potential^
carcinogenic effects of exposure to chloroform through ingestion
of water and contaminated aquatic organisms, the ambient water
concentration is zero. Concentrations of chloroform estimated to
result in additional lifetime cancer risks at the levels of
10'7, 10'6, and 10~5 were 0.000021 mg/1, 0.00021 mg/1, and
0.0021 mg/1, respectively.
No data are available regarding the behavior of chloroform in a
POTW. However, the biochemical oxidation of this compound was
studied in one laboratory scale study at concentrations higher
than those expected to be contained by most municipal waste-
waters. After 5, 10, and 20 days no degradation of chloroform
183
-------
I
was observed. The conclusion reached is that biological treat-
ment produces little or no removal by degradation of chloroform
in a POTW.
The high vapor pressure of chloroform is expected to result in
volatilization of the compound from aerobic treatment steps in a
POTW. Remaining chloroform is expected to pass through into the
POTW effluent.
Ethylbenzene (38). Ethylbenzene is a colorless, flammable liquid
manufactured commercially from benzene and ethylene. Approxi-
mately half of the benzene used in the U.S. goes into the manu-
facture of more^than three million tons of ethylbenzene annually.
Ethylbenzene boils at 136°C and has a vapor pressure of 7 mm Hg
at 20 C. It is slightly soluble in water (0.14 g/1 at 15°C) and
is very soluble in organic solvents.
About 98 percent of the ethylbenzene produced in the U.S. goes
into the production of styrene, much of which is used in the
plastics and- synthetic rubber industries. ! Ethylbenzene is a con-
stituent of xylene mixtures used as diluents in the paint indus-
try, agricultural insecticide sprays, and gasoline blends.
i
Although humans are exposed to ethylbenzene from a variety of
sources in the environment, little information on effects of
ethylbenzene in man or animals is available. Inhalation can
irritate eyes, affect the respiratory tract, or cause vertigo.
In laboratory animals ethylbenzene exhibited low toxicity. There
are no data available on teratogenicity, mutagenicity, or car-
cinogenicity of ethylbenzene.
Criteria are based on data derived from inhalation exposure
limits. For the protection of human health from the toxic prop-
erties of ethylbenzene ingested through water and contaminated
aquatic organisms, the ambient water quality criterion is 1.1
mg/1. ;
The behavior of ethylbenzene in a POTW has not been studied in
detail. Laboratory scale studies of the biochemical oxidation of
ethylbenzene at concentrations greater than would normally be
found in municipal wastewaters have demonstrated varying degrees
of degradation. In one study with phenol-acclimated seed
cultures, 27 percent degradation was observed in a half day at
250 mg/1 ethylbenzene. Another study at unspecified conditions
showed 32, 38, and 45 percent degradation after 5, 10, and 20
days, respectively. Based on these results and general observa-
tions relating molecular structure of degradation, the conclu-
sion is reached that biological treatment produces only mod-
erate removal of ethylbenzene in a POTW by degradation.
184
-------
Other studies suggest that most of the ethybenzene entering a
POTW is removed from the aqueous stream to the sludge. The
ethylbenzene contained in the sludge removed from the POTW may
volatilize.
Methylene Chloride (44). Methylene chloride, also called dichlo-
romethane ' (CH?Cl2), is a colorless liquid manufactured by
chlorination of methane or methyl chloride followed by separation
from the higher chlorinated methanes formed as coproducts.
Methylene chloride boils at 40°C, and has a vapor pressure ofQ362
mm Hg at 20°C. It is slightly soluble in water (20 g/1 at 20 C) ,
and very soluble in organic solvents. U.S. annual production is
about 250,000 tons.
Methylene chloride is a common industrial solvent found in
insecticides, metal cleaners, paint, and paint and varnish
removers.
Methylene chloride is not generally regarded as highly toxic to
humans. Most human toxicity data are for exposure by inhalation.
Inhaled methylene chloride acts as a central nervous system
depressant. There is also evidence that the compound causes
heart failure when large amounts are inhaled.
Methylene chloride does produce mutation in tests for this
effect. In addition, a bioassay recognized for its extremely
high sensitivity to strong and weak carcinogens produced results
which were marginally significant. Thus potential carcinogenic
effects of methylene chloride are not confirmed or denied,, but
are under continuous study. Difficulty in conducting and inter-
preting the test results from the low boiling point (40 C) of
methylene chloride which increases the difficulty ofQmaintaining
the compound in growth media during incubation at 37 C; and from
the difficulty of removing all impurities, some of which might
themselves be carcinogenic.
For the protection of human health from the toxic properties of
methylene chloride ingested through water and contaminated
aquatic organisms, the ambient water criterion is 0.002 mg/1.
The behavior of methylene chloride in a POTW has not been studied
in any detail. However, the biochemical oxidation of this com-
pound was studied in one laboratory scale study at concentrations
higher than those expected to be contained by most municipal
wastewaters. After five days no degradation of methylene^chlo-
ride was observed. The conclusion reached is that .biological
treatment produces little or no removal by degradation of
methylene chloride in a POTW.
The high vapor pressure of methylene chloride is expected to
result in volatilization of the compound from aerobic treatment
steps in a POTW. It has been reported that methylene chloride
185
-------
Inhibits anerobic processes in a POTW. Methylene chloride that
is not volatilized in the POTW 'is expected to pass through into
the effluent.
Naphthalene (55). Naphthalene is an aromatic hydrocarbon with
two orthocondensed benzene rings and a molecular formula of
ClO^S' As such It is properly classed as a polynuclear
aromatic hydrocarbon (PAH). Pure naphthalene is a white crystal-
line solid melting at 80°C. For a solid, it has a relatively
high vapor pressure (0.05 mm Hg at 20°C), and moderate water
solubility (19 mg/1 at 20°C). Napthalene is the most abundant
single component of coal tar. Production is more than a third of
a million tons annually in the U.S. About three fourths of the
production is used as feedstock for phthalic anhydride manufac-
ture. Most of the remaining production goes into manufacture of
insecticide, dyestuffs, pigments, and pharmaceuticals. Chlori-
nated and partially hydrogenated naphthalenes are used in some
solvent mixtures. Naphthalene is also used as a moth repellent.
Naphthalene, ingested by humans, has reportedly caused vision
loss (cataracts), hemolytic anemia, and occasionally, renal dis-
ease. These effects of naphthalene ingestion are confirmed by
studies on laboratory animals. No carcinogenicity studies are
available which can be used to demonstrate carcinogenic activity
for naphthalene. Naphthalene does bioconcentrate in aquatic
organisms.
!
For the protection of human health from the toxic properties of
naphthalene ingested through water and through contaminated
aquatic organisms, the ambient water criterion is determined to
be 143 mg/1.
Only a limited number of studies have been conducted to determine
the effects of naphthalene on aquatic organisms. The data from
those studies show only moderate toxicity.
Naphthalene has been detected in sewage plant effluents at con-
centrations up to 0.022 mg/1 in studies carried out by the U.S.
EPA. Influent levels were not reported. The behavior of naph-
thalene in a POTW has not been studied. However, recent studies
have determined that naphthalene will accumulate in sediments at
100 times the concentration in overlying water. These results
suggest that naphthalene will be readily removed by primary and
secondary settling in a POTW, if it is not biologically degraded.
Biochemical oxidation of many of the toxic organic pollutants has
been investigated in laboratory scale studies at concentrations
higher than would normally be expected in municipal wastewaters.
General observations relating molecular structure to ease of
degradation have been developed for all of these pollutants. The
186
-------
conclusion reached by study of the limited data is that biologi-
cal treatment produces a high removal by degradation of naphthal-
ene. One recent study has shown that microorganisms can degrade
naphthalene, first to a dihydro compound, and ultimately to
carbon dioxide and water.
N-nitrosodiphenylamine (62). N-nitrosodiphenylamine
UCfiHOoNNOj, also called nitrous diphenylamide, is a
yellow crystalline solid manufactured by nitrosation of diphenyl-
amine. It melts at 66°C and is insoluble in water, but soluble
in several organic solvents other than hydrocarbons. Production
in the U.S. has approached 1,500 tons per year. The compound is
used as a retarder for rubber vulcanization and as a pesticide
for control of scorch (a fungus disease of plants).
N-nitroso compounds are acutely toxic to every animal species_
tested and are also poisonous to humans. N-nitrosodiphenylamine
toxicity in adult rats lies in the mid range of the values for 60
N-nitroso compounds tested. Liver damage is the principal toxic
effect. N-nitrosodiphenylamine, unlike many other N-nitroso-
amines, does not show mutagenic activity. N-nitrosodiphenylamine
has been reported by several investigations to be non-carcino-
genic. However, the compound is capable of trans-nitrosation and
could thereby convert other amines to carcinogenic N-nitroso-
amines. Sixty-seven of 87 N-nitrosoamines studied were reported
to have carcinogenic activity. No water quality criterion have
been proposed for N-nitrosodiphenylamine.
No data are available on the behavior of N-nitrosodiphenylamine
in a POTW. Biochemical oxidation of many of the toxic organic
pollutants have been investigated, at least in laboratory scale
studies, at concentrations higher than those expected to be con-
tained in most municipal wastewaters. General observations have
been developed relating molecular structure to ease of degrada-
tion for all the toxic organic pollutants. The conclusion
reached by study of the limited data is that biological treatment
produces little or no removal of N-nitrosodiphenylamine in a
POTW. No information is available regarding possible interfer-
ence by N-nitrosodiphenylamine in POTW processes, or on the
possible detrimental effect on sludge used to amend soils in
which crops are grown. However, no interference or detrimental
effects are expected because N-nitroso compounds are widely dis-
tributed in the soil and water environment, at low concentra-
tions, as a resu t of microbial action on nitrates and
nitrosatable compounds.
Phthalate Esters (66-71). Phthalic acid, or 1,2-benzene-
dicarboxylic acid, is one of three isomeric benzenedicarboxylic
acids produced by the chemical industry. The other two isomeric
forms are called isophthalic and terephthalic acids. The formula
for all three acids is C6H4(COOH)2- Some esters of
187
-------
phthalic acid are designated as toxic pollutants. They will be
discussed as a group here, and specific properties of individual
phthalate esters will be discussed afterwards.
Phthalic acid esters are manufactured in the U.S. at an annual
rate in excess of one billion pounds. They: are used as plasti-
cizers - primarily in the production of polyvinyl chloride (PVC)
resins. The most widely used phthalate plasticizer is bis
(2-ethylhexyl) phthalate (66) which accounts for nearly one-third
of the phthalate esters produced. This particular ester is com-
monly referred to as dioctyl phthalate (DOP) and should not be
confused with one of the less used esters, di-n-octyl phthalate
(69), which is also used as a plasticizer. In addition to these
two isomeric dioctyl phthalates, four other esters, also used
primarily as plasticizers, are designated as toxic pollutants.
They are: butyl benzyl phthalate (67), di-n-butyl phthalate
(68), diethyl phthalate (70), and dimethyl phthalate (71).
Industrially, phthalate esters are prepared from phthalic anhy-
dride and the specific alcohol to form the ester. Some evidence
is available suggesting that phthalic acid esters also may be
synthesized by certain plant and animal tissues. The extent to
which this occurs in nature is not known.
Phthalate esters used as plasticizers can be present in concen-
trations up to 60 percent of the total weight of the PVC plastic.
The plasticizer is not linked by primary chemical bonds to the
PVC resin. Rather, it is locked into the structure of intermesh-
ing polymer molecules and held by van der Waals forces. The
result is that the plasticizer is easily extracted. Plasticizers
are responsible for the odor associated with new plastic toys or
flexible sheet that has been contained in a sealed package.
Although the phthalate esters are not soluble or are only very
slightly soluble in water, they do migrate into aqueous solutions
placed in contact with the plastic. Thus, industrial facilities
with tank linings, wire and cable coverings;, tubing, and sheet
flooring of PVC are expected to discharge some phthalate esters
in their raw waste. In addition to their use as plasticizers,
phthalate esters are used in lubricating oils and pesticide car-
riers. These also can contribute to industrial discharge of
phthalate esters.
From the accumulated data on acute toxicity;in animals, phtha-
late esters may be considered as having a rather low order of
toxicity. Human toxicity data are limited. '• It is thought that
the toxic effects of the esters is most likely due to one of the
metabolic products, in particular the monoester. Oral acute tox-
icity in animals is greater for the lower molecular weight esters
than for the higher molecular weight esters.
188
-------
Orally administered phthalate esters.generally produced enlarging
of liver and kidney, and atrophy of testes in laboratory animals.
Specific esters produced enlargement of heart and brain, spleen-
itis, and degeneration of central nervous system tissue.
Subacute doses administered orally to laboratory animals produced
some decrease in growth and degeneration of the testes. Chronic
studies in animals showed similar effects to those found in acute
and subacute studies, but to a much lower degree. The same
organs were enlarged, but pathological changes were not usually
detected.
A recent study of several phthalic esters produced suggestive but
not conclusive evidence that dimethyl and diethyl phthalates have
a cancer liability. Only four of the six toxic pollutant esters
were included in the study. Phthalate esters do bioconcentrate
in fish. The factors, weighted for relative consumption of
various aquatic and marine food groups, are used to calculate
ambient water quality criteria for four phthalate esters. The
values are included in the discussion of the specific esters.
Studies of toxicity of phthalate esters in freshwater and salt
water organisms are scarce. A chronic toxicity test with bis (2-
ethylhexyl) phthalate showed that significant reproductive
impairment occurred at 0.003 mg/1 in the freshwater crustacean,
Daphnia magna. In acute toxicity studies, saltwater fish and
organisms showed sensitivity differences of up to eight-fold to
butyl benzyl, diethyl, and dimethyl phthalates. This suggests
that each ester must be evaluated individually for toxic effects.
The behavior of phthalate esters in a POTW has not been studied.
However, the biochemical oxidation of many of the toxic organic
pollutants has been investigated in laboratory scale studies_at
concentrations higher than would normally, be expected in munici-
pal wastewaters. Three of the phthalate esters were studed.
Bis(2-ethylhexyl) phthalate was found to be degraded slightly or
not at all and its removal by biological treatment in a POTW is
expected to be slight or zero. Di-n-butyl phthalate and diethyl
phthalate were degraded to a moderate degree and their removal by
biological treatment in a POTW is expected to occur to a moderate
degree. Using these data and other observations relating molecu-
lar structure to ease of biochemical degradation of other toxic
organic pollutants, the conclusion was reached that butyl benzyl
phthalate and dimethyl phthalate would be removed in a POTW to a
moderate degree by biological treatment. On the same basis, it
was concluded that di-n-octyl phthalate would be removed to a
slight degree or not at all. An EPA study of seven POTW facili-
ties revealed that for all but di-n-octyl phthalate, which was
not studied, removals ranged from 62 to 87 percent.
189
-------
No information was found on possible interference with POTW oper-
ation or the possible effects on sludge by the phthalate esters.
The water insoluble phthalate esters - butyl benzyl and di-n-
octyl phthalate - would tend to remain in sludge, whereas the
other four toxic pollutant phthalate esters with water solubili-
ties ranging from 50 mg/1 to 4.5 mg/1 would probably pass through
into the POTW effluent.
i
Bis(2-ethylhexyl) phthalate (66). In addition to the general
remarks and discussion on phthalate esters, specific information
on bis(2-ethylhexyl) phthalate is provided. Little information
is available about the physical properties of bis(2-ethylhexyl)
phthalate. It is a liquid boiling at 387°C at 5mm Hg and is
insoluble in water. Its formula is CgH^COOCgHiy^-
This toxic pollutant constitutes about one-third of the phthalate
ester production in the U.S. It is commonly referred to as
dioctyl phthalate, or DOP, in the plastics industry where it is
the most extensively used compound for the plasticization of
polyvinyl chloride (PVC). Bis(2-ethylhexyl) phthalate has been
approved by the FDA for use in plastics in contact with food.
Therefore, it may be found in wastewaters coming in contact with
discarded plastic food wrappers as well as the PVC films and
shapes normally found in industrial plants. This toxic pollutant
is also a commonly used organic diffusion pump oil, where its low
vapor pressure is an advantage.
For the protection of human health from the toxic properties of
bis(2-ethylhexyl) phthalate ingested through water and through
contaminated aquatic organisms, the ambient water quality criter-
ion is determined to be 15 mg/1. If contaminated aquatic organ-
isms alone are consumed, excluding the consumption of water, the
ambient water criteria is determined to be 50 mg/1.
Although the behavior of bis(2-ethylhexyl) phthalate in a POTW
has not been studied, biochemical oxidation of this toxic pollu-
tant has been studied on a laboratory scale at concentrations "
higher than would normally be expected in municipal wastewater.
In fresh water with a non-acclimated seed culture no biochemical
oxidation was observed after 5, 10, and 20 days. However, with
an acclimated seed culture, biological oxidation occured to the
extents of 13, 0, 6, and 23 percent of theoretical after 5, 10,
15 and 20 days, respectively. Bis(2-ethylhexyl) phthalate
concentrations were 3 to 10 mg/1. Little or no removal of
bis(2-ethylhexyl) phthalate by biological treatment in a POTW is
expected.
Butyl benzyl phthalate (67). In addition to the general remarks
and discussion on phthalate esters, specific information on butyl
benzyl phthalate is provided. No information was found on the
physical properties of this compound.
190
-------
Butyl benzyl phthalate is used as a plasticizer for PVC. Two
special applications differentiate it from other phthalate
esters. It is approved by the U.S. FDA for food contact in
wrappers and containers; and it is the industry standard_for
plasticization of vinyl flooring because it provides stain
resistance.
No ambient water quality criterion is proposed for butyl benzyl
phthalate.
Butyl benzyl phthalate removal in a POTW by biological treatment
is expected to occur to a moderate degree.
Pi-n-butyl phthalate (68). In addition to the general remarks
and discussion on phtESTate esters, specific information on di-
n-butyl phthalate (DBF) is provided, DBF is a colorless, oil
liquid, boiling at 3406C. Its water solubility at room tempera-
ture is reported to be 0.4 g/1 and 4.5 g/1 in two different chem-
istry handbooks. The formula for DBF, CeH^COOCAHg^
is the same as for its isomer, di-isobutyl phthalate. DBF
production is 1 to 2 percent of total U.S. phthalate ester
production.
Dibutyl phthalate is used to a limited extent as a plasticizer
for polyvinyl chloride (PVC). It is not approved for contact
with food. It is used in liquid lipsticks and as a diluent for
polysulfide dental impression materials. DBF is used as a plas-
ticizer for nitrocellulose in making gun powder, and as a fuel in
solid propellants for rockets. Further uses are insecticides,
safety glass manufacture, textile lubricating agents, printing
inks, adhesives, paper coatings, and resin solvents.
For protection of human health from the toxic properties of
dibutyl phthalate ingested through water and through contami-
nated aquatic organisms, the ambient water quality criterion is
determined to be 34 mg/1. If contaminated aquatic organisms
alone are consumed, excluding the consumption of water, the
ambient water criterion is 154 mg/1.
Although the behavior of di-n-butyl phthalate in a POTW has not
been studied, biochemical oxidation of this toxic pollutant has
been studied on a laboratory scale at concentrations higher than
would normally be expected in municipal wastewaters. Biochemical
oxidation of 35, 43, and 45 percent of theoretical oxidation were
obtained after 5, 10, and 20 days, respectively, using sewage
microorganisms as an unacclimated seed culture.
Biological treatment in a POTW is expected to. remove di-n-butyl
phthalate to a moderate degree.
191
-------
••}!• r'f!11"1-'":1"'" :'. Itli''?•'' '"I11! ''
., BPf . if,"I i
Di-n-octyl phthalate (69) . In addition to the general remarks
and discussion on phthalate esters, specific information on
di-n-octyl phthalate is provided. Di-n-octyl phthalate is not to
be confused with the isomeric bis (2-ethylhexyl) phthalate which
is commonly referred to in the plastics industry as DOP. Di-n-
octyl phthalate is a liquid which boils at 220°C at 5 mm Hg. It
is insoluble in water. Its molecular formula is CgH/^-
(COOCgHiy^- Its production constitutes about 1 percent of
all phthalate ester production in the U.S;
Industrially, di-n-octyl phthalate is used to plasticize poly-
vinyl chloride (PVC) resins.
No ambient water quality criterion is proposed for di-n-octyl
phthalate .
Biological treatment in a POTW is expected to lead to little or
no removal of di-n-octyl phthalate.
J * \ [[[
Dimethyl phthalate (71). In addition to the general remarks and
discussion on phthalate esters, specific information on dimethyl
phthalate (BMP) is provided. BMP has the lowest molecular weight
of the phthalate esters - M.W. = 194 compared to M.W. of 391 for
bis (2-ethylhexyl) phthalate. DMP has a boiling point of 282°C.
It is a colorless liquid, soluble in water to the extent of 5
mg/1. Its molecular formula is
Dimethyl phthalate production in the U.S. iis just under one per-
cent of total phthalate ester production. DMP is used to some
extent as a plasticizer in cellulosics ; however, its principal
specific use is for dispersion of polyvinylidene fluoride (PVDF) .
PVDF is resistant to most chemicals and finds use as electrical
insulation, chemical process equipment (particularly pipe) , and
as a case for long-life finishes for exterior metal siding. Coil
coating techniques are used to apply PVDF dispersions to aluminum
or galvanized steel siding.
For the protection of human health from the toxic properties of
dimethyl phthalate ingested through water iand through contami-
nated aquatic organisms, the ambient water criterion is deter-
mined to be 313 mg/1. If contaminated aquatic organisms alone
are consumed, excluding the consumption of water, the ambient
water criterion is 2,900 mg/1.
Based on limited data and observations relating molecular struc-
ture to ease of biochemical degradation of other toxic organic
pollutants, it is expected that dimethyl phthalate will be bio-
-------
Polynuclear Aromatic Hydrocarbons (72-84). The polynuclear aro-
matic hydrocarbons(PAH) selected as toxic pollutants are a group
of 13 compounds consisting of substituted and unsubstituted poly-
cyclic aromatic rings. The general class of PAH includes hetero-
cyclics, but none of those were selected as toxic pollutants.
PAH are formed as the result of incomplete combustion when
organic compounds are burned with insufficient oxygen. PAH are
found in coke oven emissions, vehicular emissions, and volatile
products of oil and gas burning. The compounds chosen as toxic
pollutants are listed with their structural formula and melting
point (m.p.). All are insoluble in water.
72
73
74
75
76
77
78
79
80
81
82
83
Benzo(a)anthracene (1,2-benzanthracene)
Benzo(a)pyrene (3,4-benzopyrene)
3,4-Benzofluoranthene
m.p,
m.p,
m. p,
162°C
176°C
168°C
Benzo(k)fluoranthene (11,12-benzofluoranthene)
m.p
Chrysene (1,2-benzphenanthrene)
Acenaphthylene
HC=GH
Anthr.acene
Benzo(ghi)perylene (1,12-benzoperylene)
m.p <
Fluorene (alpha-diphenylenemethane)
Phenanthrene
Dibenzo(a,h)anthracene (1,2,5,6-
dibenzoanthracene)
Indeno (1,2,3-cd)pyrene
(2,3-o-phenylenepyrene)
m.p.
217°C
m.p.255°C
m.p,
92 °C
84 Pyrene
m.p. 216°C
, not reported
m.p. 116°C
m.p. 101°C
m.p. 269°C
not available
m.p. 156°C
193
-------
Some of these toxic pollutants have commercial or industrial
uses. Benzo(a)anthracene, benzo(a)pyrene, chrysene, anthracene,
dibenzo(a,h)anthracene, and pyrene are all used as antioxidants.
Chrysene, acenaphthylene, anthracene, fluorene, phenanthrene, and
pyrene are all used for synthesis of dyestuffs or other organic
chemicals. 3,4-Benzofluoranthrene, benzo(k)fluoranthene, benzo-
(ghi)perylene, and indeno (1,2,3-cd)pyrene have no known indus-
trial uses, according to the results of a recent literature
search. \
Several of the PAH toxic pollutants are found in smoked meats, in
smoke flavoring mixtures, in vegetable oils, and in coffee. Con-
sequently, they are also found in many drinking water supplies.
The wide distribution of these pollutants in complex mixtures
with the many other PAHs which have not been designated as toxic
pollutants results in exposures by humans that cannot be associ-
ated with specific individual compounds.
The screening and verification analysis procedures used for the
toxic organic pollutants are based on gas chromatography (GC).
Three pairs of the PAH have identical elution times on the column
specified in the protocol, which meansvthat the parameters of the
pair are not differentiated. For these three pairs [anthracene
(78) - phenanthrene (81); 3,4-benzofluoranthene (74) - benzo(k)-
fluoranthene (75); and benzo(a)anthracene (72) - chrysene (76)]
results are obtained and reported as "either-or." Either both
are present in the combined concentration reported, or one is
present in the concentration reported.
There are no studies to document the possible carcinogenic risks
to humans by direct ingestion. Air pollution studies indicate an
excess of lung cancer mortality among workers exposed to large
amounts of PAH containing materials such as coal gas, tars, and
coke-oven emissions. However, no definite proof exists that the
PAH present in these materials are responsible for the cancers
observed.
1
Animal studies have demonstrated the toxicity of PAH by oral and
dermal administration. The carcinogenicity of PAH has been
traced to formation of PAH metabolites which, in turn, lead to
tumor formation. Because the levels of PAHj which induce cancer
are very low, little work has been done on other health hazards
resulting from exposure. It has been established in animal
studies that tissue damage and systemic toxicity can result from
exposure to non-carcinogenic PAH compounds.
194
-------
Because there were no studies available regarding chronic oral
exposures to PAH mixtures, proposed water quality criteria were
derived using data on exposure to a single compound. Two studies
were selected, one involving benzo(a)pyrene ingestion and one
involving dibenzo(a,h)anthracene ingestion. Both are known
an imal c ar c ino gen s.
For the maximum protection of human health from the potential
carcinogenic effects of expsure to polynuclear aromatic hydrocar-
bons (PAH) through ingestion of water and contaminated aquatic
organisms, the ambient water concentration is zero. Concentra-
tions of PAH estimated to result in additional risk of 1 in
100,000 were derived by the EPA and the Agency is^considering
setting criteria at an interim target risk level in the range of
10~7 10~°, or 10~5 with corresponding criteria of
0.000000097 mg/1, 0.00000097 mg/1, and 0.0000097 mg/1,
respectively.
No standard toxicity tests have been reported for freshwater or
saltwater organisms and any of the 13 PAH discussed here.
The behavior of PAH in a POTW has received only a limited amount
of study. If is reported that up to 90 percent of PAH entering a
POTW will be retained in the sludge generated by conventional
sewage treatment processes. Some of the PAH can inhibit bac-
terial growth when they are present at concentrations as^low as
0.018 mg/1. Biological treatment in activated sludge units has
been shown to reduce the concentration of phenanthrene^and
anthracene to some extent; however, a study of biochemical oxi-
dation of fluorene on a laboratory scale showed no degradation
after 5, 10, and 20 days. On the basis of that study and studies
of other toxic organic pollutants, some general observations were
made relating molecular structure to ease of degradation. Those
observations lead to the conclusion that the 13 PAH selected to
represent that group as toxic pollutants will be removed °nly
slightly or not at all by biological treatment methods in a POTW.
Based on their water insolubility and tendency to attach to sedi-
ment particles very little pass through of PAH to POTW effluent
is expected.
No data are available at this time to support any conclusions
about contamination of land by PAH on which sewage sludge con-
taining PAH is spread.
Tetrachloroethylene (85). Tetrachlorbethylene (CC12CC12),
also called perchloroethylene and PCE, is a colorless, nonflam-
mable liquid, produced mainly by two methods - chlorination and
pyrolysis of ethane and propane, and oxychlorination of dichloro-
ethane. U.S. annual production exceeds 300,000 tons. PCE boils
at 121°C and has a vapor pressure of 19 mm Hg at 20 C. It is
insoluble in water but soluble in organic solvents.
195
-------
Approximately two-thirds of the U;S. production of PCE is used
for dry cleaning. Textile processing and! metal degreasing, in
equal amounts consume about one-quarter of the U.S. production.
The principal toxic effect of PCE on humans is central nervous
system depression when the compound is inhaled. Headache,
fatigue, sleepiness, dizziness, and sensations of intoxication
are reported. Severity of effects increases with vapor concen-
tration. High integrated exposure (concentration times duration)
produces kidney and liver damage. Very limited data on PCE
ingested by laboratory animals indicate liver damage occurs when
PCE is administered by that route. PCE tends to distribute to
fat in mammalian bodies.
One report found in the literature suggests, but does not con-
clude, that PCE is teratogenic. PCE has been demonstrated to be
a liver carcinogen in B6C3-F1 mice.
For the maximum protection of human health from the potential
carcinogenic effects of exposure to tetrachlorethylene through
ingestion of water and contaminated aquatic organisms, the ambi-
ent water concentration is zero. Concentrations of tetrachloro-
ethylene estimated to result in additional lifetime cancer risk
levels of 10- ', ICT5, and 10~5 are 0.000020 mg/1, 0.00020
mg/1, and 0.0020 mg/1, respectively.
No data were found regarding the behavior of PCE in a POTW. Many
of the toxic organic pollutants have been investigated, at least
in laboratory scale studies, at concentrations higher than those
expected to be contained by most municipal wastewaters. General
observations have been developed relating molecular structure to
ease of degradation for all of the toxic organic pollutants. The
conclusions reached by the study of the limited data is that
biological treatment produces a moderate removal of PCE in a POTW
by degradation. No information was found to indicate that PCE
accumulates in the sludge, but some PCE is expected to be -
adsorbed onto settling particles. Some PCE is expected to be
volatilized in aerobic treatment processes! and little, if any, is
expected to pass through into the effluent from the POTW.
Toluene
Toluene is a clear, colorless liquid with a
odor. It is a naturally occuring compound derived
Some
benzene
primarily from petroleum or petrochemical processes. __
toluene is obtained from the manufacture of "metallurgical coke.
Toluene is also referred to as totuol, methylbenzene , methacide.
and phenylme thane. It is an aromatic hydrocarbon with the
formula C6H5CH3. It boils at 111°C and has a vapor pres-
sure of 30 mm Hg at room temperature. The water solubility of
toluene is 535 mg/1, and it is miscible with a variety of organic'
solvents. Annual production of toluene in the U.S. is greater
than two million metric tons. Approximately two-thirds of the
196
-------
toluene is converted to benzene 'and the remaining 30 percent is
d?v?ded approximately equally into chemical manufacture, and use
as a paint solvent and aviation gasoline additive. An esti-
mated 5,000 metric tons is discharged to the environment anually
as a constituent in wastewater.
Most data on the effects of toluene in human and other mammals
have been based on inhalation exposure or dermal contact studies.
There appear to be no reports of oral administration of toluene
SnumS Subjects. A long term toxicity study on female rats
revealed no adverse effects on growth, mortality, appearance and
behavior, organ to body weight ratios, blood-urea nitrogen
leveTsTboneSmarrow counts, peripheral blood counts, or morphol-
ogy of major organs. The effects of inhaled toluene_on the cen-
tral nervous system, both at high and low concentrations, have ^
blen studied in humans and animals. However ingested toluene is
expected to be handled differently by the body because it is
absorbed more slowly and must first pass through the liver before
reaching the nervous system. Toluene is extensively and rapidly
metabolized in the liver. One of the principal metabolic prod-
ucts of toluene is benzoic acid, which itself seems to have
little potential to produce tissue injury.
Toluene does not appear to be teratogenic in laboratory animals
or man. Nor is there any conclusive evidence that toluene is
mutagenic. Toluene has not been demonstrated to be positive in
any in vitro mutagenicity or carcinogenicity bioassay system, nor
to be carcinogenic in animals or man.
Toluene has been found in fish caught in harbor waters in the
vicinity of petroleum and petrochemical plants. Bioconcentration
Itudies have not been conducted, but bioconcentration factors
have been calculated on the basis of the octanol-water partition
coefficient.
For the protection of human health from the toxic properties of
toluene ingested through water and through contaminated aquatic
organisms, the ambient water criterion is determined to be 14.3
me/1 If contaminated aquatic organisms alone are consumed
excluding £he consumption of water, the ambient water criterion
is 424 mg/1. Available data show that the adverse effects on
aquatic life occur at concentrations as low as 5 mg/1.
Acute toxicity tests have been conducted with toluene and a
variety of freshwater fish and Daphnia magna. ^%la"^ *
to be significantly more resistant tKIn-TTiK. No test results
have been reported for the chronic effects of toluene on
freshwater fish or invertebrate species.
No detailed study of toluene behavior in a POTW is available.
However, the biochemical oxidation of many of the toxic pollu-
tants has been investigated in laboratory scale studies at
197
-------
concentrations greater than those expected to be contained by
most municipal wastewaters. At toluene concentrations ranging
from 3 to 250 mg/1 biochemical oxidation proceeded to 50 percent
of theoretical or greater. The time period varied from a few
hours to 20 days depending on whether or not the seed culture was
acclimated. Phenol adapted acclimated seed cultures gave the
most rapid and extensive biochemical oxidation.
Based on study of the limited data, it is expected that toluene
will be biochemically oxidized to a lesser extent than domestic
sewage by biological treatment in a POTW. The volatility and
relatively low water solubility of toluene lead to the expecta-
tion that aeration processes will remove significant quantities
of toluene from the POTW. The EPA studied toluene removal in
seven POTW facilities. The removals ranged from 40 to 100
percent. Sludge concentrations of toluene ranged from 54 x
10~J to 1.85 mg/1.
Trichloroethylene (87^. Trichloroethylene (1,1,2-trichloroethyl-
ene or TCE) is a clear, colorless liquid boiling at 87°C. It has
a vapor pressure of 77 mm Hg at room temperature and is slightly
soluble in water (1 gm/1). U.S. production is greater than 0.25
million metric tons annually. It is produced from tetrachloro-
ethane by treatment with lime in the presence of water.
TCE is used for vapor phase degreasing of metal parts, cleaning
and drying electronic components, as a solvent for paints, as a
refrigerant, for extraction of oils, fats, and waxes, and for dry
cleaning. Its widespread use and relatively high volatility
result in detectable levels in many parts of the environment.
Data on the effects produced by ingested TCE are limited. Most
studies have been directed at inhalation exposure. Nervous sys-
tem disorders and liver damage are frequent results of inhalation
exposure. In the short term exposures, TCE acts as a central
nervous system depressant - it was used as an anesthetic before
its other long term effects were defined.
TCE has been shown to induce transformation in a highly sensitive
J§ vltro Fischer rat embryo cell system (F1706) that is used for
identifying carcinogens. Severe and persistent toxicity to the
liver was recently demonstrated when TCE was shown to produce
carcinoma of the liver in mouse strain B6C3F1. One systematic
8tud.y of TCE exposure and the incidence of human cancer was based
on 518 men exposed to TCE. The authors of that study concluded
that although the cancer risk to man cannot be ruled out, expo-
sure to low levels of TCE probably does not present a very
serious and general cancer hazard.
198
-------
TCE is bioconcentrated in aquatic species, making the consumption
of such species by humans a significant source of TCE. For the
protection of human health from the potential carcinogenic
effects of exposure to trichloroethylene through ingestion of
water and contaminated aquatic organisms, the ambient water con-
centration is zero. Concentrations of trichloroethylene e^tx-
mated to result in additional lifetime cancer risks of 10 ,
10-6, and 10-5 are 2.7 x lO'4 mg/1, 2.7 x 10 •* mg/1, and
2 7 x 10'2 mg/1, respectively. If contaminated aquatic organ-
isms alone are consumed, excluding the consumption of water the
water concentration should be less than 0.807 mg/1 to keep the
additional lifetime cancer risk below 10~3.
Only a very limited amount of data on the effects of TCE on
freshwater aquatic life are available. One species of fish (fat-
head minnows) showed a loss of equilibrium at concentrations
below those resulting in lethal effects.
The behavior of trichloroethylene in a POTW has not been studied.
However, in laboratory scale studies of toxic organic PollutantB,
TCE was subjected to biochemical oxidation conditions. Alter i,
10 and 20 days no biochemical oxidation occurred. On the basis
of'this study and general observations relating molecular struc-
ture to ease of degradation, the conclusion is reached that TCE
would undergo no removal by biological treatment in a POTW. The
volatility Snd relatively low water solubility of TCE is expected
to result in volatilization of some of the TCE in aeration steps
in a POTW.
Antimony (114). Antimony (chemical name - stibium, symbol Sb) ,
classifiecns--a non-metal or metalloid, is.a silvery white, brit-
tle crystalline solid. Antimony is found in small ore bodies_
throughout the world. Principal ores are oxides of mixed anti-
mony valences, and an oxysulfide ore. Complex ores with metals
are important because the antimony is recovered as a by-product.
Antimony melts at 631°C, and is a poor conductor of electricity
and heat.
Annual U.S. consumption of primary antimony ranges from 1,0,000 to
20,000 tons. About half is consumed in metal products - mostly
antimonial lead for lead acid storage batteries, *ndm^out half
in non-metal products. A principal compound is antimony trioxide
which is used as a flame retardant in fabrics, and as an opaci-
fier in glass, ceramics, and enamels. Several antimony compounds
are used as catalysts in organic chemicals synthesis, as fluori-
nating agents (the antimony fluoride), as pigments, and ^fire-
works! Semiconductor applications are economically significant.
Essentially no information on antimony-induced^human health
effects has been derived from community epidemiology studies.
The available data are in literature relating effects observed
199
-------
with therapeutic or medicinal uses of antimony compounds and
industrial exposure studies. Large therapeutic doses of anti-
monial compounds, usually used to treat schistisomiasis, have
caused severe nausea, vomiting, convulsions, irregular heart
action, liver damage, and skin rashes. Studies of acute
industrial antimony poisoning have revealed loss of appetite,
diarrhea, headache, and dizziness in addition to the symptoms
found in studies of therapeutic doses of antimony.
i
For the protection of human health from the toxic properties of
antimony ingested through water and through contaminated aquatic
organisms the ambient water criterion is determined to be 0.146
mg/1. If contaminated aquatic organisms are consumed, excluding
the consumption of water, the ambient water criterion is deter-
mined to be 45 mg/1. Available data show that adverse effects on
aquatic life occur at concentrations higher than those cited for
human health risks.
Very little information is available regarding the behavior of
antimony in a POTW. The limited solubility of most antimony
compounds expected in a POTW, i.e., the oxides and sulfides, sug-
gests that at least part of the anfeimony entering a POTW will be
precipitated and incorporated into the sludge. However, some
antimony is expected to remain dissolved and pass through the
POTW into the effluent. Antimony compounds remaining in the
sludge under anaerobic conditions may be connected to stibine
(SbH3), a very soluble and very toxic compound. There are no
data to show antimony inhibits any POTW processes. Antimony is
not known to be essential to the growth of plants, and has been
reported to be moderately toxic. Therefore, sludge containing
large amounts of antimony could be detrimental to plants if it is
applied in large amounts to cropland.
i
Arsenic (115). Arsenic (chemical symbol As), is classified as a
non-metal or metalloid. Elemental arsenic normally exists in the
alpha-crystalline metallic form which is steel gray and brittle,
and in the beta form which is dark gray and amorphous. Arsenic
sublimes at 615°C. Arsenic is widely distributed throughout the
world in a large number of minerals. The most important commer-
cial source of arsenic is as a by-product from treatment of
copper, lead, cobalt, and gold ores. Arsenic is usually marketed
as the trioxide (As2°3)- Annual U.S. production of the tri-
oxide approaches 40,000 tons.
The principal use of arsenic is in agricultural chemicals (herbi-
cides) for controlling weeds in cotton fields. Arsenicals have
various applications in medicinal and vetrinary use, as wood
preservatives, and in semiconductors.
i
The effects of arsenic in humans were known by the ancient Greeks
and Romans. The principal toxic effects are gastrointestinal
200
-------
disturbances. Breakdown of red blood cells occurs. Symptoms of
acute poisoning include vomiting, diarrhea, abdominal pain,
lassitude, dizziness, and headache. Longer exposure produced
dry, falling hair, brittle, loose nails, eczema, and exfoliation.
Arsenicals also exhibit teratogenic and mutagenic effects in
humans. Oral administration of arsenic compounds has been
associated clinically with skin cancer for nearly one hundred
years. Since 1888 numerous studies have linked occupational
exposure and therapeutic administration of arsenic compounds to
increased incidence of respiratory and skin cancer.
For the maximum protection of human health from the potential
carcinogenic effects of exposure to arsenic through ingestion of
water and contaminated aquatic organisms, the ambient water con-
centration is zero. Concentrations of arsenic estimated to
result in additional lifetime cancer risk levels of 10~',
ID"6, and 1C)-5 are 2.2 x 1CT7 mg/1, 2.2 x 10"b mg/1, and
2.2 x 10"5 mS/1» respectively. If contaminated aquatic organ-
isms alone are consumed, excluding the consumption of water, the
water concentration should be less than 1.75 x 10~^ to keep the
increased lifetime cancer risk below 10~5. Available data show
that adverse effects on aquatic life occur at concentrations
higher than those cited for human health risks.
A few studies have been made regarding the behavior of arsenic in
a POTW. One EPA survey of nine POTW facilities reported influent
concentrations ranging from 0.0005 to 0.693 mg/1; effluents from
three a POTW having biological treatment contained 0.0004 to 0.01
mg/1; two POTW facilities showed arsenic removal efficiencies of
50 and 71 percent in biological treatment. Inhibition of treat-
ment processes by sodium arsenate is reported to occur at 0.1
mg/1 in activated sludge, and 1.6 mg/1 in anaerobic digestion
processes. In another study based'on data from 60 POTW facili-
ties, arsenic in sludge ranged from 1.6 to 65.6 mg/kg and the
median value was 7.8 mg/kg. Arsenic in sludge spread on cropland
may be taken up by plants grown on that land. Edible plants can
take up arsenic, but normally their growth is inhibited before
the plants are ready for harvest.
Cadmium (118). Cadmium is a relatively rare metallic element
that is selclom found in sufficient quantities in a pure state to
warrant mining or extraction from the earth's surface. It^is
found in trace amounts of about 1 ppm throughout the earth s
crust. Cadmium is, however, a valuable by-product of zinc pro-
duction.
Cadmium is used primarily as an electroplated metal, and is found
as an impurity in the secondary refining of zinc, lead, and
copper.
201
-------
Cadmium Is'an extremely dangerous cumulative toxicant, causing
progressive chronic poisoning in mammals, fish, and probably
other organisms. The metal is not excreted.
Toxic effects of cadmium on man have been reported from through-
out the world. Cadmium may be a factor in the development of
such human pathological conditions as kidney disease, testicular
tumors, hypertension, arteriosclerosis, growth inhibition,
chronic disease of old age, and cancer. Cadmium is normally
ingested by humans through food and water as well as by breathing
air contaminated by cadmium dust. Cadmium is cumulative in the
liver,, kidney, pancreas, and thyroid of humans and other animals.
A severe bone and kidney syndrome known as itai-itai disease has
been documented in Japan as caused by cadmium ingestion via
drinking water and contaminated irrigation water. Ingestion of
as little as 0.6 mg/day has produced the disease. Cadmium acts
synergistically with other metals. Copper and zinc substantially
increase its toxicity.
Cadmium is concentrated by marine organisms, particularly
molluscs, which accumulate cadmium in calcareous tissues and in
the viscera. A concentration factor of 1,000 for cadmium in fish
muscle has been reported, as have concentration factors of 3,000
in marine plants and up to 29,600 in certain marine animals. The
eggs and larvae of fish are apparently more sensitive than adult
fish to poisoning by cadmium, and crustaceans appear to be more
sensitive than fish eggs and larvae. j.
For the protection of human health from the toxic properties of
cadmium ingested through water and through contaminated aquatic
organisms, the ambient water criterion is determined to be 0.010
mg/1. Available data show that adverse effects on aquatic life
occur at concentrations in the same range as those cited for
human health, and they are highly dependent on water hardness.
Cadmium is not destroyed when it is introduced into a POTW, and
will either pass through to the POTW effluent or be incorporated
into the POTW sludge. In addition, it can interfere with the
POTW treatment process.
In a study of 189 POTW facilities, 75 percent of the primary
plants, 57 percent of the trickling filter! plants, 66 percent of
the activated sludge plants, and 62 percent of the biological
plants allowed over 90 percent of the influent cadmium to pass
through to the POTW effluent. Only two of the 189 POTW facili-
ties allowed less than 20 percent pass-through, and none less
than 10 percent pass-through. POTW effluent concentrations
ranged from 0.001 to 1.97 mg/1 (mean 0.028 mg/1, standard
deviation 0.167 mg/1).
202
-------
-rpA«ses the level of cadmxuia i_n tne so3.i* ud-ud &>u.uw uu.c*i_
t • — t*«. -?-i-» ^»/-*>--r\j^-r'a •f'fiH into C2TOOS « 3_nC JLXlCl-LtlS
c3.dnn.uiii Cciti De incorpoi. a.L.CVJ. .L.I.J.t-^ N^J_ ^ f > ^^
• JT f-amiTifli'^d Qoils Since trie cirops wt*-^-*—«— — • —
land.
Chromium
Chromium is an elemental metal usually found as
CroOO- The metal is normally produced by
educng tte oxide2wJth aluminum. A significant proportion of -
?he cSomLm used is in the form of compounds ~ch JB sodrum
dichromate (Na2Cr04) , and chromic acid (Cr03) both are
hexavalent chromium compounds.
inhibitors for closed water circulation systems.
in its various valence states, is hazardous to man. It
sis'irs =
mSrtons that show no effect in man
prohibit determination, to date.
to be so low as to
203
-------
For the protection of human health from the toxic properties of
chromium (except hexavalent chromium) ingested through waS? and
contaminated aquatic organisms , the ambitnt water quality" crite-
rion is 170 mg/1. If contaminated aquatic organisms alone are
Jxcl^dfnS the consumption 2f water, Sthe amb?en? water
^ium ^ 3>443 mg/1. The ambient
hexavalent chromium is recommended to
Chromium is not destroyed when treated by a POTW (althoueh P
a.f?in Stft& ^y ?hanse) » and wil1 ei^er pass through to ?he
effu
-------
concentrations of total chromium of over 20,000 mg/kg (dry basis)
have been observed. Disposal of sludges containing very bj-gh'
concentrations of trivalent chromium can potentially cause prob-
lems in uncontrolled landfills. Incineration or similar • .
destructive oxidation processes, can produce hexavalent chromium
from lower valence states. Hexavalent chromium is potentially
more toxic than trivalent chromium. In cases where high rates ot
chrome sludge application on land are used, distinct growth
inhibition and plant tissue uptake have been noted.
Pretreatment of discharges substantially reduces the concentra-
tion of chromium in sludge. In Buffalo, New York, pretreatment
of electroplal-ine waste resulted in a decrease in chromium con-
cen?ratio£s in POTW sludge from 2,510 to 1,040 mg/kg. A similar
reduction occurred in Grand Rapids, Michigan, POTW facilities
where the chromium concentration in sludge decreased from 11,000
to 2,700 mg/kg when pretreatment was made a requirement.
Copper (120). Copper is a metallic element that sometimes is
l§Snf-fr^ras thS native metal, and is also found in minerals
such as cuprite (Cu20), malechite [CuC03.Cu(OH)2], azunte
[2CuCOvCu(OH)2], chalcopyrite (CuFeS2), and bornite
(CuqFeS/J. Copper is obtained from these ores by smelting,
leaching and electrolysis. It is used in the plating electri-
cal, plumbing, and heating equipment industries, as well as in
insecticides and fungicides.
Traces of copper are found in all forms of plant and animal life,
and the metal is an essential trace element for-nutrition.
Copper is not considered to be a cumulative systemic poison for
humans as it is readily excreted by the body,.but it can cause
symptoms of gastroenteritis, with nausea and intestinal irrita-
tions , as relatively low dosages. The limiting factor in domes-
tic water supplies is taste. To prevent this adverse organolep-
tic effect of copper in water, a criterion of 1 mg/JL has been
established.
The toxicity of copper to aquatic organisms varies significantly,
not only with the species, but also with the physical and chemi-
cal characteristics of the water, including temperature', hard-
nSss turbidity, and carbon dioxide content. In hard water, the
?Sxicity of copper salts may be reduced by the precipitation of
copper carbonatS or other insoluble compounds. The sulfates of
copper and zinc, and of copper and calcium are synergistic in
their toxic effect on fish.
Relatively high concentrations of copper may be tolerated by
adult fish fo? short periods of time; the critical effect of
copper appears to be its higher toxicity to young or juvenile
fish. Concentrations of 0.02 to 0.03 mg/1 have proved fatal to
some common fish species. In general the salmonoids are very
sensitive and the sunfishes are less sensitive to copper.
205
-------
The recommended criterion to protect freshwater aquatic life is
0.0056 mg/1 as a 24-hour average, and 0.012 mg/1 maximum concen-
tration at a hardness of 50 mg/1 CaCOa. For total recoverable
copper the criterion to protect freshwater aquatic life is 0.0056
mg/1 as a 24-hour average.
Copper salts cause undesirable color reactions in the food indus-
try and cause pitting when deposited on some other metals such as
aluminum and galvanized steel. To control undesirable taste and
odor quality of ambient water due to the organoleptic properties
of copper, the estimated level is 1.0 mg/1 for total recoverable
copper. !~
Irrigation water containing more than minute quantities of copper
can be detrimental to certain crops. Copper appears in all
soils, and its concentration ranges from 10 to 80 ppm. In soils,
copper occurs in association with hydrous oxides of manganese and
iron, and also as soluble and insoluble complexes with organic
matter. Copper is essential to the life of plants, and the
normal range of concentration in plant tissue is from 5 to 20
ppm. Copper concentrations in plants normally do not build up to
high levels when toxicity occurs. For example, the concentra-
tions of copper in snapbean leaves and pods was less than 50 and
20 mg/kg, respectively, under conditions of severe copper toxic-
ity. Even under conditions of copper toxicity, most of the
excess copper accumulates in the roots; very little is moved to
the aerial part of the plant.
i
Copper is not destroyed when treated by a POTW, and will either
pass through to the POTW effluent or be retained in the POTW
sludge. It can interfere with the POTW treatment processes and
can limit the usefulness of municipal sludge.
The influent concentration of copper to a POTW has been observed
by the EPA to range from 0.01 to 1.97 mg/1, with a median concen-
tration of 0.12 mg/1. The copper that is removed from the
influent stream of a POTW is absorbed on the sludge or appears in
the sludge as the hydroxide of the metal. Bench scale pilot
studies have shown that from about 25 percent to 75 percent of
the copper passing through the activated sludge process remains
in solution in the final effluent. Four-hour slug dosages of
copper sulfate in concentrations exceeding 50 mg/1 were reported
to have severe effects on the removal efficiency of an unaccli-
mated system, with the system returning to normal in about 100
hours. Slug dosages of copper in the form of copper cyanide were
observed to have much more severe effects oh the activated sludge
system, but the total system returned to normal in 24 hours.
In a recent study of 268 POTW facilities, the median pass-through
was over 80 percent for primary plants and 40 to 50 percent for
trickling filter, activated sludge, and biological treatment
206
-------
plants. POTW effluent concentrations of^copper ranged from 0.003
to 1.8 mg/1 (mean 0.126, standard deviation 0.242).
Copper which does not pass through the POTW will be retained in
S!PSu5ge where it will build up ^ concentration The presence
of excessive levels of copper in sludge may limit its use on
cropland? Sewage sludge contains up to 16,000 mg/kg of copper,
w?th 730 mg/kg Is the mean value. These concentrations are
significantly greater than those normally found in soil, which
usually rangl from 18 to 80 mg/kg. Experimental data indicate
that when dried sludge is spread over tillable land the copper
tends to remain in place down to the depth of.the tillage, except
for copper which is taken up by plants grown in the soil. Recent
investigation has shown that the extractable copper content of
sludge-treated soil decreased with time, which suggests a rever-
sion of copper to less soluble forms was occurring.
Cyanide (121). Cyanides are among the most toxic of pollutants
cgmmoniy-^o^sirved in industrial wastewaters. production of
cyanide into industrial processes is usually by dissolution of
potassium cyanide (KCN) or sodium cyanide (NaCN) in process
waters. However, hydrogen cyanide (HCN) formed when the above
Tails are dissolved in water, is probably the most acutely lethal
compound.
The relationship of pH to hydrogen cyanide formation is very
important. As pH is lowered to below 7, more than 99 percent of
JS lyaSide is present as HCN and less than 1 percent ^ as cyanide
ions. Thus, at neutral pH, that of most living organisms, the
more toxic form of cyanide prevails.
Cyanide ions combine with numerous heavy metal ions to form com-
plexes . The complexes are in equilibrium with HCN. Thus the
Stability of the metal-cyanide complex and the pH determine the
concentration of HCN. Stability of the metal-cyanide anion com-
plexes is extremely variable.' Those formed with zinc, copper
and cadmium are not stable - they rapidly dissociate with pro-
duction of HCN, in near neutral or acid waters. Some of^the com
plexes are extremely stable. Cobaltocyanide is very resistant to
acid distillation in the laboratory. Iron cyanide complexes are
also stable, but undergo photodecomposition to give HCN uPon
exposure to sunlight. Synergistic effects have been demonstrated
for Se inSal cyanide complexes making zinc,,copper, and cadmium
cyanides more toxic than an equal concentration of sodium
cyanide.
The toxic mechanism of cyanide is essentially an inhibition of
oxygen metabolism, i.e., rendering the tissues incapable of
exchanging oxygen! The cyanogen compounds are tr^efln°n|^a^Ve
protoplasmic poisons. They arrest the activity of all forms of
animal life. Cyanide shows a very specific type of toxic action.
207
-------
I
It inhibits the cytochrome oxidase system. This system is the
one which facilitates electron transfer from reduced metabolites
to molecular oxygen. The human body can convert cyanide to a
non-toxic thiocyanate and eliminate it. However, if the quantity
ot cyanide ingested is too great at one time, the inhibition of
oxygen utilization proves fatal before the detoxifying reaction
reduces the cyanide concentration to a safe level.
Cyanides are more toxic to fish than to lower forms of aquatic
organisms such as midge larvae, crustaceans, and mussels. Toxic-
5 ^S-, ^S a f"11^1011 of chemical form and concentration, and
is influenced by the rate of metabolism (temperature), the level
of dissolved oxygen, and pH. In laboratory studies free cyanide
concentrations ranging from 0.05 to 0.14 mg/1 have been proven to
S6,.^* *° sensitive fish species including trout, bluegill, and
fathead minnows. Levels above 0.2 mg/1 are rapidly fatal to most
tish species. Long term sublethal concentrations of cyanide as
low as 0.01 mg/1 have been shown to affect the ability of fish to
function normally, e.g., reproduce, grow, and swim.
For the protection of human health from the toxic properties of
cyanide ingested through water and through contaminated aquatic
£fSn onnS) ?he ambient water quality criterion is determined to
be 0.200 mg/1.
Persistence of cyanide in water is highly variable and depends
upon the chemical form of cyanide in the water, the concentration
ot cyanide, and the nature of other constituents. Cyanide may be
destroyed by strong oxidizing agents such as permanganate and
cnlonne. Chlorine is commonly used to oxidize strong cyanide
solutions. Carbon dioxide and nitrogen are the products of com-
plete oxidation. But if the reaction is not complete, the very
toxic compound, cyanogen chloride, may remain in the treatment
system and subsequently be released to the environment. Partial
chlorination may occur as part of a PQTW treatment, or during the
disinfection treatment of surface water for drinking water prW-
aration. r ?
Cyanides can interfere with treatment processes in a POTW or
pass through to ambient waters. At low concentrations and with
acclimated microflora, cyanide may be decomposed by microorga-
nisms in anaerobic and aerobic environments or waste treatment
systems. However, data indicate that much of the cyanide intro-
duced passes^through to the POTW effluent. The mean pass-through
S£TIT * ?}OS?-cal Plantswas 71 percent. In a recent study of 41
POTW facilities the effluent concentrations ranged from 0.002 to
*SLm8/1 ^ea? =-2:518» standard deviation = 15.6). Cyanide also
enhances the toxicity of metals commonly found in POTW effluents '
including the toxic pollutants cadmium, zincj and copper. '
208
-------
Data for Grand Rapids, Michigan, showed a significant decline in
cyanide concentrations downstream from the POTW^after pretreat-
ment regulations were put in force. Concentrations fell from
0.66 mg?l before, to 0.01 mg/1 after pretreatment was required.
i
Lead (122). Lead is a soft, malleable, ductile, blueish-gray
Seta-lTTc-ilement, usually obtained from the mineral galena (lead
sulfide, PbS), anglesite (lead sulfate, PbSO*), or cerussite
(lead carbonate, PbC03). Because it is usually associated with
minerals of zinc, silver, copper, gold, cadmium, antimony, and
arsenic, special purification methods are frequently used before
and after extraction of the metal from the ore concentrate by
smelting.
Lead is widely used for its corrosion resistance sound and
vibration absorption, low melting point (solders), and relatively
high imperviousness to various forms of radiation. Small amounts
of copper, antimony and other metals can be alloyed with lead to
achieve greater hardness, stiffness, or corrosion resistance than
is afforded by the pure metal. Lead compounds are used in glazes
and paints. About one third of U.S. lead consumption goes into
storage batteries. About half of U.S. lead consumption is from
secondary lead recovery. U.S. consumption of lead is in the
range of one million tons annually.
Lead ingested by humans produces a variety of toxic effects
including impaired reproductive ability, disturbances in blood
chemistry", neurological disorders, kidney damage, and adverse
cardiovascular effects. Exposure to lead in the diet results in
permanent increase in lead levels in the body. Most of the lead
entering the body eventually becomes localized in the bones where
it accumulates. Lead is a carcinogen or cocarcinogen in some ^
species of experimental animals. Lead is teratogenic in experi-
mental animals. Mutagenicity data are not available for lead.
The ambient water quality criterion for lead is recommended to be
identical to the existng drinking water standard which is 0.050
mg/1. Available data show that adverse effects on aquatic lite
occur at concentrations as low as 7.5 x ICT^ mg/1 of total
recoverable lead as a 24-hour average with a water hardness of 50
mg/1 as CaC03.
Lead is not destroyed in a POTW, but is passed through to the
effluent or retained in the POTW sludge; it can interfere with
POTW treatment processes and can limit the usefulness of POTW
sludge for application to agricultural croplands. Threshold con-
centration for inhibition of the activated sludge process is 0.1
mg/1, and for the nitrification process is 0.5 mg/1. In a study
of 2l4 POTW facilities, median pass through values were over 80
percent for primary plants and over 60 percent for trickling
209
-------
filter, activated sludge, and biological process plants. Lead
concentration in POTW effluents ranged from 0.003 to 1.8 mg/1
(mean - 0.106 mg/1, standard deviation = 0.222).
Application of lead-containing sludge to cropland should not lead
to uptake by crops under most conditions because normally lead is
strongly bound by soil. However, under the unusual condition of
low pH (less than 5.5) and low concentrations of labile phos-
phorus, lead solubility is increased and plants can accumulate
lead. ,
i
Nickel (124). Nickel is seldom found in nature as the pure ele-
mental metal. It is a relatively plentiful element and is widely
distributed throughout the earth's crust. It occurs in marine
organisms and is found in the oceans. The chief commercial ores
for nickel are pentlandite [(Fe,Ni)9Sg], and a laterltic ore
consisting of hydrated nickel-iron-magnesium silicate.
Nickel has many and varied uses. It is used in alloys and as the
pure metal. Nickel salts are used for electroplating baths.
The^toxicity of nickel to man is thought to be very low, and sys-
temic poisoning of human beings by nickel or nickel salts is
almost unknown. In non-human mammals nickel acts to inhibit
insulin release, depress growth, and reduce cholesterol. A high
incidence of cancer of the lung and nose has been reported in
humans engaged in the refining of nickel.
Nickel salts can kill fish at very low concentrations. However,
nickel has been found to be less toxic to some fish than copper,
zinc, and iron. Nickel is present in coastal and open ocean
water at concentrations in the range of 0.0001 to 0.006 mg/1
although the most common values are 0.002 to 0.003 mg/1. Marine
animals contain^up to 0.4 mg/1 and marine plants contain up to 3
mg/1. Higher nickel concentrations have been reported to cause
reduction in photosynthetic activity of the giant kelp. A low
concentration was found to kill oyster eggs.
For the protection of human health based on the toxic properties
of nickel ingested through water and through contaminated aquatic
organisms, the ambient water criterion is determined to be 0.0134
mg/1. If contaminated aquatic organisms are consumed, excluding
consumption of water, the ambient water criterion is determined
to be 0.100 mg/1. Available data show that adverse effects on
aquatic life occur for total recoverable nickel concentrations as
low as 0.0071 mg/1 as a 24-hour average.
Nickel is not destroyed when treated in a POTW, but will either
pass through to the POTW effluent or be retained in the POTW
sludge. It can interfere with POTW treatment processes and can
also limit the usefulness of municipal sludge.
210
-------
Nickel salts have caused inhibition of the biochemical oxidation
of sewage in a POTW. In a pilot plant, slug doses of nickel
significantly reduced normal treatment efficiencies for a tew
hoSrs but the plant acclimated itself somewhat to the slug dos-
aae and appeared to achieve normal treatment efficiencies ^ within
40 hours. It has been reported that the anaerobic digestion pro-
cess is inhibited only by high concentrations of nickel, while a
low concentration of nickel inhibits the nitrification process.
The influent concentration of nickel to a POTW has been observed
by the EPA to range from 0.01 to 3.19 mg/1, with a median of 0. 33
me/1 In a study of 190 POTW facilities, nickel pass-through was
e?eater than 90 percent for 82 percent of the primary plants .
Median pass-through for trickling filter, activated sludge and
biological process plants was greater than 80 percent. POTW
effluent concentrations ranged from 0.002 to 40 mg/1 (mean -
0.410, standard, deviation = 3.279).
Nickel not passed through the POTW will be incorporated into the
sludge. In a recent two-year study of eight cities, four of the
cities had median nickel concentrations of over 350 mg/kg, and
two were over 1,000 mg/kg. The maximum nickel concentration
observed was 4,010 mg/kg.
Nickel is found in nearly all soils, plants, and waters. Nickel
has no known essential function in plants. In soils, nickel
typically is found in the range from 10 to 100 mg/kg. Various
environemntal exposures to nickel appear to correlate with _
increased incidence of tumors in man. For example, cancer in the
maxillary antrum of snuff users may result from using plant
materials grown on soil high in nickel.
Nickel toxicity may develop in plants from application of sewage
sludge on acid soils. Nickel has caused reduction of yields for
a variety of crops including oats, mustard, turnips, and cabbage.
In one study nickel decreased the yields of oats significantly at
100 mg/kg.
Whether nickel exerts a toxic effect on plants depends on several
soil factors, the amount of nickel applied, and the contents ot
other metals in the sludge. Unlike copper and zinc, which are
more available from inorganic sources than from sludge, nickel
uptake by plants seems to be promoted by the presence of the
organic matter in sludge. Soil treatments, such as liming, ^
reduce the solubility ^ of nickel. Toxicity of nickel to plants is
enhanced in acidic soils.
Selenium (125).
element
Selenium (chemical symbol Se) is a non-metallic
in several allotropic forms. Gray selenium,
"
element, e-x.jLsuj-i.ig j-n o^v^j-^j- "••*-' * - . -
which has a metallic appearance, is the stable form at ordinary
temperatures and melts at 220°C e«i^4,,m-*a * ^-.OT- mnmonent
Selenium is a major component
211
-------
of 38 minerals and a minor component of 37 others found in
various parts of the world. Most selenium is obtained as a
by-product of precious metals recovery from electrolytic copper
refinery slimes. U.S. annual production at one time reached one
million pounds.
frii' », • ••' " ,
Principal uses of selenium are in semi-conductors, pigments,
decoloring of glass, zerography, and metallurgy. It also is used
to produce ruby glass used in signal lights. Several selenium
compounds are important oxidizing agents in!the synthesis of
organic chemicals and drug products.
While results of some studies suggest that selenium may be an
essential element in human nutrition, the toxic effects of
selenium in humans are well established. Lassitude, loss of
hair, discoloration and loss of fingernails are symptoms of
selenium poisoning. In a fatal case of ingestion of a larger
dose of selenium acid, peripheral vascular collapse, pulmonary
edema, and coma occurred. Selenium produces mutagenic and tera-
togenic effects, but it has not been established as exhibiting
carcinogenic activity. '
For the protection of human health from the toxic properties of
selenium ingested through water and through • contaminated aquatic
organisms, the ambient water criterion is determined to be 0.010
mg/1, i.e., the same as the drinking water standard. Available
data show that adverse effects on aquatic life occur at con-
centrations higher than that cited for human toxicity.
Very few data are available regarding the behavior of selenium in
a POTW. One EPA survey of 103 POTW facilities revealed one POTW
using biological treatment and having selenium in the influent.
Influent concentration was 0.0025 mg/1, effluent concentration
was 0.0016 mg/1, giving a removal of 37 percent. It is not known
to be inhibitory to POTW processes. In another study, sludge
from POTW facilities in 16 cities was found to contain from 1.8
to 8.7 mg/kg selenium, compared to 0.01 to 2 mg/kg in untreated
soil. ^These concentrations of selenium in sludge present a
potential hazard for humans or other mammals eating crops grown
on soil treated with selenium-containing sludge.
Silver (126). Silver is a soft, lustrous, white metal that is
insoluble in water and alkali. In nature, silver is found in the
elemental state (native silver) and combined in ores such as
argentite (Ag£S), horn silver (AgCl), proustite (Ag3AsS3),
and pyrargyrite (Ag3SbS3). Silver is used extensively in
several industries, among them electroplating.
Metallic silver is not considered to be toxic, but most of its
salts are toxic to a large number of organisms. Upon ingestion
212
-------
by humans, many silver salts are absorbed in the circulatory sys-
tem and deposited in various body tissues, resulting in_general-
ized or sometimes localized gray pigmentation of the skin and
mucous membranes known as argyria. There is no known method for
removing silver from the tissues once it is deposited, and the
effect is cumulative.
Silver is recognized as a bactericide and doses from 0.000001 to
0.0005 mg/1 have been reported as sufficient to sterilize water.
The criterion for ambient water to protect human health from the
toxic properties of silver ingested through water and through
contaminated aquatic organisms is 0.010 mg/1.
The chronic toxic effects of silver on the aquatic environment
have not been given as much attention as many other heavy metals.
Data from existing literature support the fact that silver is
very toxic to aquatic organisms. Despite the fact that silver is
nearly the most toxic of the heavy metals, there are insufficient
data to adequately evaluate even the effects of hardness^on
silver toxicity. There are no data available on the toxicity of
different forms of silver.
There is no available literature on the incidental removal of
silver by a POTW. An incidental removal of about 50 percent is
assumed as being representative. This is the highest average
incidental removal of any metal for which data are available.
(Copper has been indicated to have a median incidental removal
rate of 49 percent.)
Bioaccumulation and concentration of silver from sewage sludge
has not been studied to any great degree. There is some indica-
tion that silver could be bioaccumulated in mushrooms to the
extent that there could be adverse physiological effects on
humans if they consumed large quantities of mushrooms grown in
silver enriched soil. The effect, however, would tend to be
unpleasant rather than fatal.
There is little summary data available on the quantity of silver
discharged to a POTW. Presumably there would be a tendency to
limit its discharge from a manufacturing facility because of its
high intrinsic value.
Thallium (I27±. Thallium (Tl) is a soft, silver-white, dense,
malleable metal. Five major minerals contain 15 to 85 percent
thallium, but they are not of commercial importance because the
metal is produced in sufficient quantity as a by-product of lead-
zinc smelting of sulfide ores. Thallium melts at 304 C. U.S.
annual production of thallium and its compounds is estimated to
be 1,500 pounds.
213
-------
Industrial uses of thallium include the manufacture of alloys,
electronic devices and special glass. Thallium catalysts are
used for industrial organic syntheses.
Acute thallium poisoning in humans has been widely described.
Gastrointestinal pains and diarrhea are followed by abnormal
sensation in the legs and arms, dizziness, and, later, loss of
hair. The central nervous system is also affected. Somnolence,
delerium or coma may occur. Studies on the teratogenicity of
thallium appear inconclusive; no studies on mutagenicity were
found; and no published reports on carcinogenicity of thallium
were found.' !
For the protection of human health from the toxic properties of
thallium ingested through water and contaminated aquatic
organisms, the ambient water criterion is 0.004 mg/1.
No reports were found regarding the behavior of thallium in a
POTW. It will not be degraded, therefore it must pass through to
the effluent or be removed with the sludge. However, since the
sulfide (T1S) is very insoluble, if appreciable sulfide is
present dissolved thallium in the influent to a POTW may be pre-
cipitated into the sludge. Subsequent use of sludge bearing
thallium compounds as a soil amendment to crop bearing soils may
result in uptake of this element by food plants. Several leafy
garden crops (cabbage, lettuce, leek, and endive) exhibit rela-
tively higher concentrations of thallium than other foods such as
meat.
Zinc (128). Zinc occurs abundantly in the earth's crust, con-
centrated in ores. It is readily refined into the pure, stable,
silver-white metal. In addition to its use in alloys, zinc is
used as a protective coating on steel. It;is applied by hot dip-
ing (i.e., dipping the steel in molten zinc) or by electroplat-
ing- ;
l
Zinc can have an adverse effect on man and animals at high con-
centrations. Zinc at concentrations in excess of 5 mg/1 causes
an undesirable taste which persists through conventional treat-
ment. For the prevention of adverse effects due to these organo-
leptic properties of zinc, 5 mg/1 was adopted for the ambient
water criterion. Available data show that adverse effects on
aquatic life occur at concentrations as low as 0.047 mg/1 as a
24-hour average.
Toxic concentrations of zinc compounds cause adverse changes in
the morphology and physiology of fish. Lethal concentrations in
the range of 0.1 mg/1 have been reported. Acutely toxic concen- '
trations induce cellular breakdown of the gills, and possibly the
clogging of the gills with mucous. Chronically toxic concentra-
tions of zinc compounds cause general enfeeblement and widespread
214
-------
histological changes to many organs, but not to gills. Abnormal
swimming behavior has been reported at 0.04 mg/1. Growth and
maturation are retarded by zinc. It has been observed that the
effects of zinc poisoning may not become apparent immediately, so
that fish removed from zinc-contaminated water may die as long as
48 hours'after removal.
In general, salmonoids are most sensitive to elemental zinc in
soft water: the rainbow trout is the most sensitive in hard
waters. A complex relationship exists between zinc concentra-
tion, dissolved zinc concentration, pH, temperature, and calcium
and magnesium concentration. Prediction of harmful effects has
been less than reliable and controlled studies have not been
extensively documented.
'•~-. _v
The major concern with zinc compounds in marine waters is not
with acute lethal effects, but rather with the long-term sub-
lethal effects of the metallic compounds and complexes. Zinc
accumulates in some marine species, and marine animals contain
zinc in the range of 6 to 1,500 mg/kg. From^the point of view of
acute lethal effects, invertebrate marine animals seem to be the
most sensitive organism tested.
Toxicities of zinc in nutrient solutions have been demonstrated
for a number of plants. A variety of fresh water plants tested
manifested harmful symptoms at concentrations of 0.030 to 21.b
me/1. Zinc sulfate has also been found to be lethal to many
plants and it could impair agricultural uses of the water.
Zinc is not destroyed when treated by a POTW, but will either
pass through to the POTW effluent or be retained in^the POTW
sludge. It can interfere with treatment processes in the POTW
and can also limit the usefulness of municipal sludge.
In slue doses, and particularly in the presence of copper, dis-
solved zinc can interfere with or seriously disrupt the operation
of POTW biological processes by reducing overall removal effi-
ciencies, largely as a result of the toxicity of the metal to
biological organisms. However, zinc solids in the form of
hydroxides or sulfides do not appear to interfere with biological
treatment processes, on the basis of available data. Such solids
accumulate in the sludge.
The influent concentrations of zinc to a POTW has been observed
by the EPA to range from 0.017 to 3.91 mg/1, with a median con-
centration of 0.33 mg/1. Primary treatment is not efficient in
removing zinc; however, the microbial floe of secondary treatment
readily adsorbs zinc.
In a study of 258 POTW facilities, the median pass-through values
were 70 to 88 percent for primary plants, 50 to 60 percent for
215
-------
trickling filter and biological process plants, and 30 to 40 per-
cent for activated process plants. POTW effluent concentrations
of zinc ranged from 0.003 to 3.6 mg/1 (mean = 0.330, standard
deviation = 0.464).
i
The zinc which does not pass through the POTW is retained in the
sludge. The presence of zinc in sludge may limit its use on
cropland. Sewage sludge contains 72 to over 30,000 mg/kg of
zinc, with 3,366 mg/kg as the mean value. These concentrations
are significantly greater than those normally found in soil,
which range from 0 to 195 mg/kg, with 94 mg/kg being a common
level. Therefore, application of sewage sludge to soil will
generally increase the concentration of zinc in the soil. Zinc
can be toxic to plants, depending upon soil pH. Lettuce, toma-
toes, turnips, mustard, kale, and beets are especially sensitive
to zinc contamination.
Oil and Grease.
tant parameter.
components are:
Oil and grease are taken together as one pollu-
This is a conventional pollutant and some of its
1. Light Hydrocarbons - These include light fuels such as
fasoline, kerosene, and jet fuel, and miscellaneous solvents used
or industrial processing, degreasing, or cleaning purposes. m1-~
presence of these light hydrocarbons may make the removal of
other heavier oil wastes more difficult.
The
2. Heavy Hydrocarbons, Fuels, and Tars - These include the
crude oils, diesel oils, #6 fuel oil, residual oils, slop oils,
and in some cases, asphalt and road tar. j
3. Lubricants and Cutting Fluids - These generally fall
into two classes: non-emulsifiable oils such as lubricating oils
and greases and emulsifiable oils such as water soluble oils,
rolling oils, cutting oils, and drawing compounds. Emulsifiable
oils may contain fat, soap, or various other additives.
!
4. Vegetable and Animal Fats and Oil's - These originate
primarily from processing of foods and natural products.
These compounds can settle or float and may exist as solids or
liquids depending upon factors such as method of use, production
process, and temperature of water.
Oil and grease even in small quantities cause troublesome taste
and odor problems. Scum lines from these agents are produced on
water treatment basin walls and other containers. Fish and water
fowl are adversely affected by oils in their habitat. Oil emul-
sions may adhere to the gills of fish causing suffocation, and
the flesh of fish is tainted when microorganisms that were
exposed to waste oil are eaten. Deposition of oil in the bottom
216
-------
sediments of water can serve to inhibit normal benthic growth.
Oil and grease exhibit an oxygen demand.
Many of the toxic organic pollutants will be found distributed
between the oil phase and the aqueous phase in industrial waste-
waters. The presence of phenols, PCB's, PAH's, and almost any
other organic pollutant in the oil and grease make characteriza-
tion of this parameter almost impossible. However, all^of these
other organics add to the objectionable nature of the oil and
grease.
Levels of oil and grease which are toxic to aquatic organisms^
vary greatly, depending on the type and the species susceptibil-
ity. However, it has been reported that crude oil in concentra-
tions as low as 0.3 mg/1 is extremely toxic to freshwater fish.
It has been recommended that public water supply sources be
essentially free from oil and grease.
Oil and grease in quantities of 100 1/sq km show up as a sheen on
the surface of a body of water. The presence of oil slicks
decreases the aesthetic value of a waterway.
Oil and grease is compatible with a POTW activated sludge process
in limited quantity. However, slug loadings or high concentra-
tions of oil and grease interfere with biological treatment
processes. The oils coat surfaces and solid particles, prevent-
ing access of oxygen, and sealing in some microorganisms. Land
spreading of POTW sludge containing oil and grease uncontamrnated
by toxic pollutants is not expected to affect crops grown on the
treated land, or animals eating those crops.
PH. Although not a specific pollutant, pH is related to the
acidity or alkalinity of a wastewater stream. It is not, how-
ever, a measure of either. The term pH is used to describe the
hydrogen ion concentration (or activity) present in a given solu-
tion. Values for pH range from 0 to 14, and these numbers are
the negative logarithms of the hydrogen ion concentrations. A pH
of 7 indicates neutrality. Solutions with a pH above 7 are alka-
line, while those solutions with a pH below 7 are acidic. The
relationship of pH and acidity and alkalinity is not necessarily
linear or direct. Knowledge of the water pH is useful in deter-
mining necessary measures for corrosion control, sanitation, and
disinfection. Its value is also necessary in the treatment of
industrial wastewaters to determine amounts of chemicals required
to remove pollutants and to measure their effectiveness. Removal
of pollutants, especially dissolved solids is affected by the pH
of the wastewater.
Waters with a pH below 6.0 are corrosive to water works struc-
tures, distribution lines, and household plumbing fixtures and
can thus add constituents to drinking water such as iron, copper,
217
-------
zinc, cadmium, and lead. The hydrogen ion concentration can
affect the taste of the water, and at a low pH water tastes sour.
The bactericidal effect of chlorine is weakened as the pH
increases, and it is advantageous to keep the pH close to 7.0.
This is significant for providing safe drinking water.
Extremes of pH or rapid pH changes can exert stress conditions or
kill aquatic life outright. Even moderate changes from accept-
able criteria limits of pH are deleterious to some species.
I
The relative toxicity to aquatic life of many materials is
increased by changes in the water pH. For example, metallocya-
nide complexes can increase a thousand-fold in toxicity with a
drop of 1.5 pH units. '
Because of the universal nature of pH and its effect on water
quality and treatment, it is selected as a pollutant parameter
for many industry categories. A neutral pH range (approximately
6 to 9) is generally desired because either extreme beyond this
range has a deleterious effect on receiving waters or the pollu-
tant nature of other wastewater constituents.
Pretreatment for regulation of pH is covered by the "General Pre-
treatment Regulations for Existing and New Sources of Pollution,"
40 CFR 403.5. This section prohibits the discharge to a POTW of
"pollutants which will cause corrosive structural damage to the
POTW but in no case discharges with pH lower than 5.0 unless the
works is specially designed to accommodate such discharges."
Total Suspended Solids (TSS). Suspended solids include both
organic and inorganic materials. The inorganic compounds include
sand, silt, and clay. The organic fraction includes such materi-
als as grease, oil, tar, and animal and vegetable waste products.
These solids may settle out rapidly, and bottom deposits are
often a mixture of both organic and inorganic solids. Solids may
be suspended in water for a time and then settle to the bed of
the stream or lake. These solids discharged with man's wastes
may be inert, slowly biodegradable materials, or rapidly decom-
posable substances. While in suspension, suspended solids
increase the turbidity of the water, reduce light penetration,
and impair the photosynthetic activity of aquatic plants.
Suspended solids in water interfere with many industrial pro-
cesses and cause foaming in boilers and incrustations on equip-
ment exposed to such water, especially as the temperature rises.
They are undesirable in process water used in the manufacture of
steel, in the textile industry, in laundries, in dyeing, and in
cooling systems.
Solids in suspension are aesthetically displeasing. When they
settle to form sludge deposits on the stream or lake bed, they
218
-------
are often damaging to the life in the water. Solids, when trans-
formed to sludge deposit, may do a variety of damaging things,
including blanketing the stream or lake bed and thereby destroy-
ing the living spaces for those benthic organisms that would
otherwise occxipy the habitat. When of an organic nature, solids
use a portion or all of the dissolved oxygen available in the
area. Organic materials also serve as a food source for
sludge worms arid associated organisms.
Disregarding any toxic effect attributable to substances leached
out by water, suspended solids may kill fish and shellfish by
causing abrasive injuries and by clogging the gills and respira-
tory passages of various aquatic fauna. Indirectly, suspended
solids are inimical to aquatic life because they screen out
light, and they promote and maintain the development of noxious
conditions through oxygen depletion. This results in the killing
of fish and fish food organisms. Suspended solids also reduce
the recreational value of the water.
Total suspended solids is a traditional pollutant which is com-
patible with a well-run POTW. This pollutant with the exception
of those components which are described elsewhere in this sec-
tion, e.g., heavy metal components, does not interfere with the
operation of a POTW. However, since a considerable portion of
the innocuous TSS may be inseparably bound to the constituents
which do interfere with POTW operation, or produce unusable
sludge, or subsequently dissolve to produce unacceptable POTW
effluent, TSS may be considered a toxic waste.
POLLUTANT SELECTION FOR COPPER FORMING WASTE STREAMS
The pollutant selection procedure was performed for the following
copper forming waste streams to select those toxic pollutants
that would be considered for establishing regulations for the
Copper Forming Category:
Cold Rolling Spent Lubricant
Hot Rolling Spent Lubricant
Drawing Spent Lubricant
Solution Heat Treatment Contact Cooling Water
Extrusion Press Heat Treatment Contact Cooling Water
Pickling Bath
Pickling Rinse
Alkaline Cleaning Bath
Alkaline Cleaning Rinse
Annealing - Water
Annealing - Oil
Pickling Fume Scrubber Water
219
-------
Pollutants Not Detected. The 112 toxic pollutants listed in
Table VI-1 were not detected in any samples from these wastewater
streams as reported in Tables V-14 through V-25 (p.100 -175)-
therefore, they were not selected .for consideration in establish-
ing regulations.
Pollutants Detected but Present at Concentrations too Small to be
Treated^The nine pollutants listed in Table VI-'1 were detected
in copper forming wastewater; however, they were found at concen-
trations which were not treatable. Therefore, they were not
selected for consideration in establishing regulations.
Pollutants Selected for Regulation. The 17 toxic pollutants
listed in Table VI-3 were those not eliminated from consideration
for any of the reasons listed above; therefore, each was selected
for consideration in establishing regulations.
The maximum concentrations of these toxic pollutants which were
found in copper forming wastewaters are presented in Table VI-4.
220
-------
.Table VI-1
POLLUTANTS NOT DETECTED IN COPPER FORMING WASTEWATER
1.' acenaphthene
2. acrolein
3. acrylonttrile
5. benzidine
6. carbon tetrachloride
7. chlorobenzene
8. 1,2,4-trichlorobenzene
9. hexachlorobenzene
10. 1,2-dichloroethane
12. hexachloroethane
13. 1,1-dichloroethane
14. 1,1,2-trichloroethane
15. 1,1,2,2-tetrachloroethane
16. chloroethane
17. DELETED
18. bis(chloroethyl)ether
19. 2-chloroethyl vinyl ether
20. 2-chlor©naphthalene
21. 2,4,6-trichlorophenol
22. p-chloro-m-cresol
24. 2-chlor©phenol
25. 1,2-dicb.lorobenzene
26. 1,3-dichlorobenzene
27. 1,4-dichlorobenzene
28. 3,3'-dichlorobenzidine
29. 1,1-dichloroethylene
30. 1,2-trans-dichloroethylene
31. 2,4-dichlorophenol
32. 1,2-dichloropropane
33. 1,3-dichloropropylene
34. 2,4-dimethylphenol
35. 2,4-dinitrotoluene
37. 1,2-diphenylhydrazine
39. fluoranthene
40. 4-chlorophenyl phenyl ether
41. 4-bromophenyl phenyl ether
42. bis(2-chloroisopropyl)ether
43. bis(2-chloroethoxy)methane
45. methyl chloride (chloromethane)
46. methyl bromide (bromomethane)
47. bromoform (tribromomethane)
48. dichlorobromomethane
49. DELETED
50. DELETED
51. chlorodibromomethane
221
-------
52.
53.
54.
56.
57.
58.
59.
60.
61.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
79.
80.
82.
83.
84.
85.
88.
89.
90.
91.
92.
93.
94.
95.
96.
97.
98.
99.
100.
101.
102.
Table VI-1 (Continued)
POLLUTANTS NOT DETECTED IN COPPER FORMING WASTEWATER
hexachlorobutadiene
hexachlorocyclopentadiene j
isophorone
nitrobenzene
2-nitrophenol .
4-nitrophenol
2,4-dinitrophenol
4,6-dinitro-o-cresol
N-nitrosodimethylamine
N-nitrosodi-n-propylamine
pentachlorophenol
phenol
bis(2-ethylhexyl)phthalate .
butyl benzyl phthalate
di-n-butyl phthalate
di-n-octyl phthalate
diethyl
dimethyl
phthalate
phthalate
benzo(a)anthracene
benzo(a)pyrene
benzo(b)fluoranthene
benzo(k)fluoranthene
chrysene
acenaphthylene
benzo(ghi)perylene
fluorene
dibenzo(a,h)anthracene
indeno(1,2,3-c,d)pyrene
pyrene
tetrachloroethylene
vinyl chloride (chloroethylene)
aldrin
dieldrin
chlordane
4,4'-DDT
4,4'-DDE
4,4'-ODD
alpha-endosulfan
beta-endosulfan
endosulfan sulfate
endrin
endrin aldehyde
heptachlor
heptachlor epoxide
alpha-BHC
222
-------
Table VI-1 (Continued)
POLLUTANTS NOT DETECTED IN COPPER FORMING WASTEWATER
103.
104.
105.
106.
107.
108.
109.
110.
111.
112.
113.
114.
115.
116.
117.
1 18 .
121.
123.
125.
126.
127.
129 .
beta-BHC
gamma- BHC
delta- BHC
PCB-1242
PCB-1254
PCB-1221
PCB-1232
PCB-1248
PCB-1260
PCB-1016
toxaphene
(a)
(a)
(a)
(a)
(b)
(b)
(b)
arsenic
asbestos
beryllium
cadmium
cyanide
mercury
selenium
silver
thallium
2,3,7 ,8-tetrachlorodibenzo-p-dioxin
(a) (b) Phenanthrene and anthracene are reported together since
they are not physically distinguishable using approved
analytical methods.
223
-------
Table VI-2
POLLUTANTS EXCLUDED FROM REGULATION BECAUSE
THEY ARE PRESENT IN AMOUNTS TOO SMALL
TO BE EFFECTIVELY TREATED
Antimony
Arsenic
Beryllium
Cadmium
Cyanide
Mercury
Selenium
Silver
Thallium
224
-------
Table VI-3
POLLUTANTS CONSIDERED FOR REGULATION
4. benzene
11. 1,1,1-trichloroethane
23. chloroform
36. 2,6-dinitrotoluene
38. ethylbenzene
44. methylene chloride
5 5. naphthalene
62. N-nitrosodiphenylamine
7 8. anthracene
81. phenanthrene
86. toluene
87. trichloroethylene
119. chromium
120. copper
122. lead
124. nickel
128. zinc
225
-------
Table VI-4
MAXIMUM CONCENTRATIONS OF TOXIC POLLUTANTS
FOUND IN COPPER FORMINQ WASTEWATERS
Toxic Pollutant
4.
11.
23.
36.
38.
44.
55.
62.
78.
81.
86.
87.
119.
120.
122.
124.
128.
benzene
1,1,1 -tr ichloroethane
chloroform
2, 6-dinitrotoluene
e thy Ib enz ene
methylene chloride
naphthalene
N-ni t r o s od ipheny 1 amine
anthracene (a)
phenanthrene (a)
toluene
trichloroethylene
chromium
copper
lead
nickel
zinc
Maximum Concentration
Observed
2.0 mg/1
0.087 mg/1
0.038 mg/1
14.0 mg/1
0.043 mg/1
0.053 mg/1
3.5 mg/1
90 mg/1
27 mg/1
27 mg/1
0.057 mg/1
0.023 mg/1
174 mg/1
24,000 mg/1
167 mg/1
385 mg/1
!45,000 mg/1
(a) Phenanthrene and anthracene are reported together since they
are not physically distinguishable using approved analytical
methods.
lr"' "!'.' '',!': '. .'!'"! : :"'i ",'""!: K. 'Will :- [[, ,; >'. :'•.•», I !!!'•,'(,' W™ I")'!
226
-------
SECTION VII
CONTROL AND TREATMENT TECHNOLOGY
This section describes the treatment techniques currently used or
available ?o remove or recover wastewater pollutants normally
generated b? the copper forming industrial point source^category.
Included are discussions of individual end-of-pipe treatment
technologiel and in -pi ant technologies. These treatment technol-
ogies art widely used in many industrial categories and data and
information to support their effectiveness has been drawn from a
similarly wide range of sources and data bases.
KND-OF-PIPE TREATMENT TECHNOLOGIES
Individual recovery and treatment technologies are described
which are used or are suitable for use in treating wastewater
discharges from copper forming facilities. Each description
?nc?udef a factional description and discussions of application
and performance, advantages and limitations, operational Actors
(reliability, maintainability, solid waste aspects) ,- and demon-
stration status. The treatment processes described include both
technologies presently demonstrated within the copper forming
category! and technologies demonstrated in treatment of similar
wastes in other industries.
Copper forming wastewater streams characteristically contain
significant levels of toxic inorganics. Chromium, copper, lead,
SlcSl^Sd zinc are found in copper forming wastewater streams
at substantial concentrations. These toxic inorganic pollutants
constitute the most significant wastewater pollutants in this
category.
In general, these pollutants are removed by oil removal
min? emulsion breaking, and flotation), chemical precipitation
aid sedimentation, or filtration. Most of them may be effec-
Svely removed by precipitation of metal hydroxides or carbonates
utilizing the reaction with lime, sodium hydroxide, or sodium
carbonate. For some, improved removals are provided by the use
of sodium sulfide or' ferrous sulfide to precipitate the pollu-
tants as sulfide compounds with very low solubilities.
Discussion of end -of -pipe treatment technologies is divided into
three parts: the major technologies; the effectiveness of major
technologies; and minor end -of -pipe technologies.
227
-------
MAJOR TECHNOLOGIES
i
In Sections IX, X, XI, and XII, the rationale for selecting
ent ^stems *:s discussed. The , individual technologies used
system are described here. The major end-of-pipe technol-
i metals, cyanide precipitation, granu-
filtration pressure filtration settling of suspended
flionShi5i?8 ?Xl» che?ical emulsion breaking, and thermal
emulsion breaking. In practice, precipitation of metals and
settling of the resulting precipitates is often a unified
two-step operation. Suspended solids originally present in raw
wastewaters are not appreciably affected by the precipitation
operation and are removed with the precipitated metals in the
settling operations. Settling operations can be evaluated
independently of hydroxide or other chemical precipitation
operations, but hydroxide and other chemical precipitation
?emovai°opera?ion"7 ^ SValuated in Combination with a solids
Chemical Reduction of Chromium
; °f the Procesg- Reduction is a chemical reaction in
which electrons are transferred to the chemical being reduced
emca eng reuce
the,che*ic*l initiating the transfer (the reducing agent).
Sulfur dioxide, sodium bisulfite, sodium metabisulf itef and
ferrous sulfate form strong reducing agents in aqueous solution
and are often used in industrial waste treatment facilities for
£oL~I:dUCt1?? °f hexavajent chromium to the trivalent form. The
?3J iS allows removal of chromium from solution in conjunction
with other metallic salts by alkaline precipitation. Hexavalent
chromium is not precipitated as the hydroxide. "exavaient
Gaseous sulfur dioxide is a widely used reducing agent and pro-
vides a good example of the chemical reduction process. Reduc-
fnSJiS8^ Ot5er.^a§ents is chemically similar. The reactions
involved may be illustrated as follows:
3S02
2H2Cr04
+ 5H20
The above reactions are favored by low pH. A pH of from 2 to 3
is normal for situations requiring complete reduction. At pH
levels above 5, the reduction rate is slow. Oxidizing agents
such as dissolved oxygen and ferric iron interfere with the
reduction process by consuming the reducing agent.
A typical treatment consists of 45 minutes retention in a
reaction tank. The reaction tank has an electronic recorder-
controller device to control process conditions with respect to
228
-------
pH and oxidation-reduction potential (ORP). Gaseous sulfur
dioxide is metered to the reaction tank to maintain the ORP
within the range of 250 to 300 millivolts. Sulfuric acid is
added to maintain a pH level of from 1.8 to 2.0. The reaction
tank is equipped with a propeller agitator designed to provide
approximately one turnover per minute. Figure VII-1 shows a
continuous chromium reduction system.
Application and Performance. Chromium reduction is used in
copper forming for treating pickling baths and pickling rinses.
Cooling tower blowdown may also contain chromium as a biocide^in
waste streams. A study of an operational waste treatment facil-
ity chemically reducing hexavalent chromium has shown that a 99.7
percent reduction efficiency is easily achieved. Reduction fol-
lowed by chemical precipitation can achieve final concentrations
of 0.05 mg/1, and concentrations of 0.01 mg/1 are considered to
be attainable by properly maintained and operated equipment.
Advantages and Limitations. The major advantage^of^chemical
reduction to reduce hexavalent chromium is that it is a fully
proven technology based on many years of experience. Operation
at ambient conditions results in low energy consumption, and the
process, especially when using sulfur dioxide, is well suited to
automatic control. Furthermore, the equipment is readily obtain-
able from many suppliers, and operation is straightforward.
One limitation of chemical reduction of hexavalent chromium is
that for high concentrations of chromium, the cost of treatment
chemicals may be prohibitive. When this situation occurs, other
treatment techniques are likely to be more economical. Chemical
interference by oxidizing agents is possible in the treatment of
mixed wastesi and the treatment itself may introduce pollutants
if not properly controlled. - Storage and handling of sulfur
dioxide is somewhat hazardous.
Operational Factors. Reliability: Maintenance consists of
periodic removal of sludge, the frequency of which is a function
of the input concentrations of detrimental constituents.
Solid Waste Aspects: Pretreatment to eliminate substances which
will interfere with the process may often be necessary. T^is^
process produces trivalent chromium which can be controlled by
further treatment. There may, however, be small amounts of
sludge collected due to minor shifts in the solubility of the
contaminants. This sludge can be processed by the main sludge
treatment equipment.
229
-------
Demonstration Status. The reduction of chromium waste by sulfur
dioxide or sodium bisulfite is a classic process and is used by
numerous plants which have hexavalent chromium compounds in
wastewaters from operations such as electroplating and coil coat-
ing. Eight copper forming plants report the use of chromium
reduction to treat pickling wastewaters. :
Chemical Precipitation
Dissolved toxic metal ions and certain anions may be chemically
precipitated for removal by physical means such as sedimentation
filtration, or centrifugation. Several reagents are commonly
used to effect this precipitation.
1. Alkaline compounds such as lime or sodium hydroxide may
be used to precipitate many toxic metal ions as metal
hydroxides. Lime also may precipitate phosphates as
insoluble calcium phosphate and fluorides as calcium
fluoride,
Both "soluble" sulfides such as hydrogen sulfide or
sodium sulfide and "insoluble" sulfides such as ferrous
sulfide may be used to precipitate many heavy metal ions
as insoluble metal sulfides.
Ferrous sulfate, zinc sulfate, or both (as is required)
may be used to precipitate cyanide as a ferro or zinc
ferricyanide complex.
Carbonate precipitates may be used to remove metals
either by direct precipitation using a carbonate
reagent such as calcium carbonate or by converting
hydroxides into carbonates using carbon dioxide.
These treatment chemicals may be added to a flash mixer or rapid
mix tank, to a presettling tank, or directly to a clarifier or
?thfri settling device- Because metal hydroxides tend to be col-
loidal in nature, coagulating agents may also be added to facili-
tate settling. After the solids have been removed, final pH
adjustment may be required to reduce the high pH created by the
alkaline treatment chemicals.
i
Chemical precipitation as a mechanism for removing metals from
wastewater is a complex process of at least two steps - precipi-
tation of the unwanted metals and removal of the precipitate.
Some small amount of metal will remain dissolved in the waste-
water after complete precipitation. The amount of residual
dissolved metal depends on the treatment chemicals used and
related factors. The effectiveness of this method of removing
any specific metal depends on the fraction ;of the specific metal
2.
3.
4.
1 - >
230
-------
in the raw waste (and hence in the precipitate) and^the effec-
tiveness of suspended solids removal. In specific instances, *
sacrificial ion such as iron or aluminum may be added to aid in
the precipitation process and reduce the fraction of a specific
metal in the precipitate.
Application and Performance. Chemical precipitation is used in
copper forming for precipitation of dissolved metals. It can be
used to remove metal ions such as antimony, arsenic, beryllium,
cadmium, chromium, cobalt, copper, iron, lead, manganese,
mercury, molybdenum, tin, and zinc. The process is also
applicable to any substance that can be transformed into an
insoluble form such as fluorides, phosphates soaps, sulfides
and others. Because it is simple and effective, chemical precip-
itation is extensively used for industrial waste treatment.
The performance of chemical precipitation depends on several
variables. The most important factors affecting precipitation
effectiveness are:
1. Maintenance of an alklaine pH throughout the
precipitation reaction and subsequent settling;
2. Addition of a sufficient excess of treatment ions to
drive the precipitation reaqtion to completion;
3. Addition of an adequate supply of sacrificial ions
(such as iron or aluminum) to ensure precipitation and
removal of specific target, ions; and
4. Effective removal of precipitated solids (see
appropriate technologies discussed under Solids
Removal").
Control of pH. Irrespective of the solids removal technology
employed, proper control of pH is absolutely essential for favor-
able performance of precipitation-sedimentation technologies.
This is clearly illustrated by solubility curves for selected
metals hydroxides and sulfides shown in Figure VII-2, and by
plotting effluent zinc concentrations against pH as shown in
Figure VII-3. Figure VII-3 was obtained from Development Docu-
ent for the Proposed Effluent Limitations Guidelines and New
Source Performance Standards foi
Metals Manufacturin
.^^^~~ the Zinc Segment of
Point Source Category^U.S.E.P.A.,
Nonferrous
"ER
Metals FianuEacLurj-uK JTKJ.I.IL. u^m.»-^ ^^.^^f,^^j, ~.~- ,
440/1-74/033, November, 1974.Figure VII-3 was plotted from the
sampling data from several facilities with metal finishing
operations. It is partially illustrated by data obtained from
three consecutive days of sampling at one metal processing plant
(47432) as displayed in Table VII-1. Flow through this system is
approximately 49,263 1/hr (13,000 gal/hr).
231
-------
This treatment system uses lime precipitation (pH adjustment)
followed by coagulant addition and sedimentation. Samples were
taken before (in) and after (out) the treatment system. The best
treatment for removal of copper and zinc was achieved on day one,
when the pH was maintained at a satisfactory level. The poorest
treatment was found on the second 'day, when the pH slipped to an
unacceptably low level and intermediate values were achieved on
the third day, when pH values were less than desirable but in
between the first and second days.
Sodium hydroxide is used by one facility (plant 439) for pH
adjustment and chemical precipitation, followed by settling
(sedimentation and a polishing lagoon) of;precipitated solids.
Samples were, taken prior to caustic addition and following the
polishing lagoon. Flow through the system is approximately
22,700 1/hr (6,000 gal/hr). Metals removal data for this system
are presented in Table VII-2.
These data indicate that the system was operated efficiently.
Effluent pH was controlled within the range of 8.6 to 9.3, and
while raw waste loadings were not unusually high, most toxic
metals were removed to very low concentrations.
Lime and sodium hydroxide are sometimes used to precipitate
metals. Data developed from plant 40063, a facility with a
metal-bearing wastewater, exemplify efficient operation of a
chemical precipitation and settling system. Table VXI-3 shows
sampling data from this system, which uses lime and sodium
hydroxide for pH adjustment, chemical precipitation, polyelec-
trolyte flocculant addition, and sedimentation. Samples were
taken of the raw waste influent to the system and of the
clarifier effluent. Flow through the system is approximately
19,000 1/hr (5,000 gal/hr).
At this plant, effluent TSS levels were below 15mg/1 on each
day, despite average raw waste TSS concentrationsof over 3,500
mg/1. Effluent pH was maintained at approximately 8, lime addi-
tion was sufficient to precipitate the dissolved metal ions, and
the flocculant addition and clarifier retention served to remove
effectively the precipitated solids.
Sulfide precipitation is sometimes used to precipitate metals
resulting in improved metals removals. Most metal sxilfides are
less soluble than hydroxides and the precipitates are frequently
more effectively removed from water. Solubilities for selected
metal hydroxide, carbonate, and sulfide precipitates are shown in
Table VII-4 (Source: Lange's Handbook of Chemistry). Sulfide
precipitation is particularly effective ia removing specific
metals such as silver and mercury. Sampling data from three
industrial plants using sulfide precipitation appear in Table
VII-5. The data were obtained from three sources:
,232
-------
1. Summary Report, Control and Treatment Technology for
the Metal Finishing Industry: Sulfide Precipitation,
USEPA, EPA No. 625/8/80-003, 1979.:
2. Industry Finishing, Vol. 35, No. 11, November/ 1979.
3. Electroplating sampling data from plant 27045.
In all cases except iron, effluent concentrations are below 0.1
mg/1 and in many cases below 0.04 mg/1 for the three plants
studied.
Sampling data from several chlorine-caustic manufacturing plants
using sulfide precipitation demonstrate effluent mercury concen-
trations varying between 0.009 and 0.03 mg/1. As shown in Figure
VII-2, the solubilities of PbS and Ag£S are lower at alkaline
pH levels than either the corresponding hydroxides or other sul-
fide compounds. This implies that removal performance for lead
and silver sulfides should be comparable to or better than that
for the heavy metal hydroxides. Bench scale tests on several
types of metal finishing and manufacturing wastewater indicate
that metals removal to levels of less than 0.05 mg/1 and in some
cases less than 0.01 mg/1 are common in systems using sulfide
precipitation followed by clarification. Some of the bench scale
data, particularly in the case of lead, do not support such low
effluent concentrations. However, lead is consistently removed
to very low levels (less than 0.02 mg/1) in systems using
hydroxide and carbonate precipitation and sedimentation.
Of particular interest is the ability of sulfide to precipitate
hexavalent chromium (Cr+6) without prior reduction to the tri-
valent state as is required in the hydroxide process. When fer-
rous sulfide is used as the precipitant, iron and sulfide act as
reducing agents for the hexavalent chromium according to the
reaction:
Gr03 + FeS + 3H20
Fe(OH)3 + Cr(OH)3 + S
The sludge produced in this reaction consists mainly of ferric
hydroxides, chromic hydroxides, and various metallic sulfides.
Some excess hydroxyl ions are generated in this process, possibly
requiring a downward readjustment of pH.
Based on the available data, Table VII-6 shows the minimum relia-
bly attainable effluent concentrations for sulfide precipitation-
sedimentation systems. These values are used to calculate
performance predictions of sulfide precipitation-sedimentation
systems. Table VII-6 is based on two reports:
233
-------
1. Summary Report, Control and Treatment Technology for the
Metal Finishing Industry: Sulfide Precipitation, USEPA.
EPA No. 625/8/80-003, 1979. '.
2. Addendum to Development Document for Effluent Limita-
tions Guidelines and New Source Performance Standards,
Major Inorganic Products Segment of Inorganics Point
Source Category, USEPA.. EPA Contract No7 EPA/68-01-
3281 (Task 7), June, 1978.
Carbonate precipitation is sometimes used to precipitate metals,
especially where precipitated metals values are to be recovered.
The solubility of most metal carbonates is intermediate between
hydroxide and sulfide solubilities; in addition, carbonates form
easily filtered precipitates.
Carbonate ions appear to be particularly useful in precipitating
lead and antimony. Sodium carbonate has been observed being
added at treatment to improve lead precipitation and removal in
some industrial plants. The lead hydroxide and lead carbonate
solubility curves displayed in Figure VII-4 ("Heavy Metals
Removal," by Kenneth Lanovette, Chemical Engineering/Deskbook
Issue, Oct. 17, 1977) explain this phenomenon.
i
Co-precipitation with Iron - The presence of substantial quanti-
ties of iron in metal-bearing wastewaters before treatment has
been shown to improve the removal of toxic metals. In some cases
this iron is an integral part of the industrial wastewater; in
other cases iron is deliberately added as a preliminary or first
step of treatment. The iron functions to improve toxic metal
removal by three mechanisms: the iron co-precipitates with toxic
metals forming a stable precipitate which desolubilizes the toxic
metal; the iron improves the settleability of the precipitate;
and the large amount of iron reduces the fraction of toxic metal
in the precipitate. Co-precipitation with iron has been prac-
ticed for many years incidentally when iron was a substantial
constituent of raw wastewater and intentionally when iron salts
were added as a coagulant aid. Aluminum or mixed iron-aluminum
salts also have been used.
Co-precipitation using large amounts of ferrous iron salts is
known as ferrite co-precipitation because magnetic iron oxide or
ferrite is formed. The addition of ferrous salts (sulfate) is
followed by alkali precipitation and air oxidation. The resul-
tant precipitate is easily removed by filtration and may be
removed magnetically. Data illustrating the performance of
ferrite co-precipitation is shown in Table VII-7. The data are
from:
1.
Sources and Treatment of Wastewater in the Nonferrous
Metals Industry, USEPA, EPA No. 600/2-80-074. 1980.
234
-------
Advantages and Limitations
Chemical precipitation has proven to be an effective technique
for removing many pollutants from industrial wastewater. It_
operates at ambient conditions and is well suited to automatic
control. The use of chemical precipitation may be limited
because of interference by chelating agents, because of possible
chemical interference of mixed wastewaters and treatment^chemi-
cals or because of the potentially hazardous situation involved
with the storage and handling of those chemicals. Lime is usu-
ally added as a slurry when used in hydroxide precipitation. Tne
slurry must be kept well mixed and the addition lines periodi-
cally checked to prevent blocking of the lines, which may result
from a buildup of solids. Also, hydroxide precipitation usually
makes recovery of the precipitated metals difficult, because of
the heterogeneous nature of most hydroxide sludges.
The major advantage of the sulfide precipitation process is that
the extremely low solubility of most metal sulfides promotes very
high metal removal efficiencies; the sulfide process also has the
ability to remove chromates and dichromates without preliminary
reduction of the chromium to its trivalent state. In addition,
sulfide can precipitate metals completed with most complexing
aaents. The. process demands care; however, in maintaining the pti
of the solution at approximately 10 in order to prevent the gen-
eration of toxic hydrogen sulfide gas. For this reason, ventila-
tion o£ the treatment tanks may be a necessary precaution in most
installations. The use of insoluble sulfides reduces the problem
of hydrogen sulfide evolution. As with hydroxide precipitation,
excess sulfide ion must be present to drive the precipitation
reaction to completion. Since the sulfide ion itself is toxic,
sulfide addition must be carefully controlled to maximize heavy
metals precipitation with a minimum of excess sulfide to avoid
the necessity of post treatment. At very high excess sulfiae _
levels and high pH, soluble mercury-sulfide compounds may aiso oe
formed. Where excess sulfide is present, aeration of the efflu-
ent stream can aid in oxidizing residual sulfide to the less
harmful sodium sulfate (Na2S04). The cost of sulfide pre.ca.p-
itants is high in comparison with hydroxide precipitants, and
disposal of metallic sulfide sludges may pose problems. An
essential element in effective sulfide precipitation is the
removal of precipitated solids from the wastewater and proper
disposal in an appropriate site. Sulfide precipitation will also
generate a higher volume of sludge than hydroxide precipitation,
resulting in higher disposal and dewatering costs. This ^ is
especially true when ferrous sulf5.de is used as the precipitanu.
Sulfide precipitation may be used as a polishing treatment after
nydroxid! precipitation-sedimentation. This treatment configura-
tion may provide the better treatment effectiveness of sulfide
235
-------
precipitation while minimizing the variability caused by changes
in raw waste and reducing the amount of sulfide precipitant
required. r
-vn Alkali*e chemical precipita-
highly reliable, although proper monitoring and control
Sulfide alitation S
con
Sulfide Palpitation Systems provide similar
tion
Pliability
Maintainability: The major maintenance needs involve periodic
upkeep of monitoring equipment, automatic feeding equipment
mixing equipment, and other hardware. Removal of accumulated
sludge is necessary for efficient operation of precipitation-
sedimentation systems.
Solid Waste Aspects: Solids which precipitate out are removed in
8t8p' Ultimate1^ these "ollds require
Demonstration Status. Chemical precipitation of metal hydroxides
is a classic waste treatment technology used by most industrial
?!££« treat*ent systems. Chemical precipitation of metals in the
carbonate form alone has been found to be feasible and is commer-
cially used to permit metals recovery and water reuse. Full
n™^00^6^1?} sulfide Precipitation units are in operation at
numerous installations. As noted earlier, sedimentation to
ff??r PreciPitates Js discussed separately. Chemical precipi-
tation is currently demonstrated at 36 copper forming plants.
Cyanide Precipitation ',
Cyanide precipitation, although a method for treating cyanide in
^thr!^ d^S.n?t destr°y ^anide. The cyanide is retained
the sludge that is formed. Reports indicate that during expo-
th\?yanide complexes can break down and for?
mo v r th:L! reason the sludge from this treatment
method must be disposed of carefully.
» **? b? P^^Pitated and settled out of wastewaters by the
addition of zinc sulfate or ferrous sulfate. In the presencJ of
ae. n te presenc of
«JS?£.?Cyan£ de.wl11 nf2rm extremely stable cyanide complexes. The
addition of zinc sulfate or ferrous sulfate forms zinc ferrocya-
nide or ferro and ferricyanide complexes.
™oiron PreciPitated cyanide requires that the PH
must be kept at 9.0 and an appropriate detention^ time be main-
tamed. A study has shown that the formation of the complex is
IonLd?Pe?dent °n PH- ,At PH s of 8 and 10 the residual cyanidl
concentrations measured are twice those of the same reaction car-
ried out at a>PH of 9. Removal efficiencies also depend heavily
on the retention time allowed. The formation of the complexes
236
-------
takes place rather slowly. Depending upon the excess amount of
zinc sulfate or ferrous sulfate added,-at least a 30 minute
retention time should be allowed for the formation of the cyanide
complex before continuing on to the clarification stage.
One experiment with an initial concentration of 10 mg/1 of cya-
nide showed that 98 percent of the cyanide was complexed 10
minutes after the addition of ferrous sulfate at twice the theo-
retical amount necessary. Interference from other metal ions,
such as cadmium, might result in the need for longer retention
times.
Table VII-8 presents data from three coil coating plants. Plant
1057 also does aluminum forming. A fourth plant was visited^for
the purpose of observing plant testing of'the cyanide precipita-
tion system. Specific data from this facility are not included
because: (1) the pH was usually well below the optimum level of
90; (2) the historical treatment data were not obtained using
the standard cyanide analysis procedure; and (3) matched_input-
output data were not made available by the plant. Scanning the
available data indicates that the raw waste CN level was in the
range of 25.0; the pH 7.5; and treated CN level was from O.I to
0.2.
The concentrations are those of the stream entering and leaving
the treatment system. Plant 1057 allowed a 27 minute retention,
time for the formation of the complex. The retention time for_
the other plants is not known. The data suggest that over a wide
ranee of cyanide concentration in the raw waste, the concentra-
tion of cyanide can be reduced in the effluent stream to under
0.15 mg/1.
Application and Performance. Cyanide precipitation can be used
when cyanide destruction is not feasible because of the presence
of cyanide complexes which are difficult to destroy. Effluent
concentrations of cyanide well below 0.15 mg/1 are possible.
Advantages and Limitations. Cyanide precipitation is an inexpen-
sive method of treating cyanide. Problems may occur when metal
ions interfere with the formation of the complexes.
Demonstration Status. Although no plants currently_use cyanide
precipitation to treat copper forming wastewaters, it is used in
at least six coil coating plants.
Granular Bed Filtration
Filtration occurs in nature as the surface ground waters are
cleansed by sand. Silica sand, anthracite coal, and garnet are
237
-------
common filter media used in water treatment plants. These are
usually supported by gravel. The media may be used singly or in
combination. The multi-media filters may be arranged to maintain
relatively distinct layers by virtue of balancing the forces of
gravity?( flow, and buoyancy on the individual particles. This is
accomplished by selecting appropriate filter flow rates (epm/sq-
ft), media grain size, and density.
Granular bed filters may be classified in terms of filtration
rate, filter media, flow pattern, or method of pressxirization.
Traditional rate classifications are slow sand, rapid sand, and
high rate mixed media. In the slow sand filter, flux or
hydraulic loading is relatively low, and removal of collected
solids to clean the filter is therefore relatively infrequent.
The filter is often cleaned by scraping off the inlet face (top)
of the sand bed. In the higher rate filters, cleaning is fre-
quent and is accomplished by a periodic backwash, opposite to the
direction of normal flow.
A"filter may use a single medium such as sand or diatomaceous
earth (Figure VII-5a), but dual (Figure VII-5d) and mixed (multi-
Pil< media (Figure Vll-Se) filters allow higher flow rates and
efficiencies. 'The dual media filter usually consists of a fine
bed of sand under a coarser bed of anthracite coal. The coarse
coal removes most of the influent solids, while the fine sand
performs a polishing function. At the end of the backwash, the
fine sand settles to the bottom because it is denser than the
coal, and the filter is ready for normal operation. The mixed
media filter operates on the same principle, with the finer
denser media at the bottom and the coarser, less dense media at
the top. The usual arrangement is garnet at the bottom (outlet
end; of the bed, sand in the middle, and anthracite coal at the
top. Some mixing of these layers occurs and is, in fact,
desirable.
The flow pattern is usually top-to-bottom, but other patterns are
sometimes used. Upflow filters (Figure VIl-5b) are sometimes
used, and in a horizontal filter the flow is horizontal. In a
biflow filter (Figure VII-5c), the influent enters both the top
and the bottom and exits laterally. The advantage of an upflow
filter is that with an upflow backwash the particles of a single
filter medium are distributed and maintained in the desired
coarse-to-fine (bottom-to-top) arrangement. The disadvantage is
that the bed tends to become fluidized, which lowers filtration
efficiency. The biflow design is an attempt to overcome this
problem.
238
-------
The classic granular bed filter operates by gravity flow; how-
ever, pressure filters are fairly widely used. They permit
higher solids loadings before cleaning and are advantageous when
the filter effluent must be pressurized for further downstream
treatment. In addition, pressure filter systems are often less
costly for low to moderate flow rates.
Figure VII-6 depicts a high rate, dual media, gravity downflow
granular bed filter, with self-stored backwash. Both filtrate
and backwash are piped around the bed in an arrangement that per-
mits gravity upflow of the backwash, with the stored filtrate
serving as backwash. Addition of the indicated coagulant and
polyelectrolyte usually results in a substantial improvement in
filter performance.
Auxiliary filter cleaning is sometimes employed in the upper few
inches of filter beds. This is conventionally referred to as
surface wash and is accomplished by water jets just below the
surface of the expanded bed during the backwash cycle. These
jets enhance the scouring action in the bed by increasing the
agitation.
An important feature for successful filtration and backwashing is
the underdrain. This is the support structure for tne bed. The
underdrain provides an area for collection of the filtered water
without clogging from either the filtered solids or the media
grains. In addition, the underdrain prevents loss of the media
with the water, and during the backwash cycle it provides even
flow distribution over the bed. Failure to dissipate the veloc-
ity head during the filter or backwash cycle will result in bed
upset and the need for major repairs.
Several standard approaches are employed for filter underdrains.
The simplest one consists of a parallel porous pipe imbedded
under a layer of coarse gravel and manifolded to a header pipe
for effluent removal. Other approaches to the underdrain system
are known as the Leopold and Wheeler filter bottoms. Both of
these incorporate false concrete bottoms with specific porosity
configurations to provide drainage and velocity head dissipation.
Filter system operation may be manual or automatic. The filter
backwash cycle may be on a timed basis, a pressure drop basis
with a terminal value which triggers backwash, or a solids carry-
over basis from turbidity monitoring of the outlet stream. All
of these schemes have been used sue cessfully.
Application and Performance. Wastewater treatment plants often
use granular bed filters tor polishing after clarification, sedi-
mentation, or other similar operations. Granular bed filtration
thus has potential application to nearly all industrial plants.
239
-------
Chemical additives which enhance the upstream treatment eauinment
may or may not be compatible with or enhance the filtration pro-
cess. Normal operation flow rates for various types of filters
are as follows:
Slow Sand
Rapid Sand
High Rate Mixed Media
2.04 - 5.30 1/sq m-hr
40.74 - 51.48 1/sq m-hr
81.48 - 122.22 1/sq m-hr
Suspended solids are commonly removed from wastewater streams by
£f}£erifS through a deeP °-3 to 0.9 m (1 to 3 feet) granular
tilter bed. The porous bed formed by the granular media can be
designed to remove practically all suspended particles. Even
colloidal suspensions (roughly 1 to 100 microns) are adsorbed on
the surface of the media grains as they pass in close proximity
in the narrow bed passages.
Properly operated filters following some preliminary treatment to
reduce suspended solids below 200 mg/1 should produce water with
less than 10 mg/1 TSS. For example, multimedia filters produced
the effluent qualities shown in Table VII-9.
Advantages and Limitations. The principal advantages of granular
bed filtration are its comparatively (to other filters) low ini-
tial and operating costs, reduced land requirements over othe>-
methods to achieve the same level of solids removal, and elimina-
tion of chemical additions to the discharge stream. However the
filter may require preliminary treatment if the solids level'is
high Cover 100 mg/1). Operator training must be somewhat exten-
sive due to the controls and periodic backwashing involved, and
backwash must be stored and dewatered for economical disposal.
Operational Factors. Reliability: The recent improvements in
f7^er technol°gy have significantly improved filtration relia-
bility. Control systems, improved designs, and good operating
procedures have made filtration a highly reliable method of water
treatment.
Maintainability: Deep bed filters may be operated with either
manual or automatic backwash. In either case, they must be peri-
odically inspected for media attrition, partial plugging, and
leakage. Where backwashing is not used, collected solids must be
removed by shoveling, and filter media must be at least partially
replaced. r J
)
Solid Waste Aspects: Filter backwash is generally recycled
within the wastewater treatment system, so that the solids ulti-
mately appear in the clarifier sludge stream for subsequent
dewatering. Alternatively, the backwash stream may be. dewatered
directly or, if there is no backwash, the collected solids may be
240
-------
disposed of in a suitable landfill. In either of these situa-
tions there is a solids disposal problem similar to that of
clarifiers.
Demonstration Status. Deep bed filters are in common use in
municipal treatment plants. Their use in polishing industrial
clarifier effluent is increasing, and the technology is proven
and conventional. Granular bed filtration is currently used at
six copper forming plants.
Pressure Filtration
Pressure filtration works by pumping the liquid through a filter
material which is impenetrable to the solid phase. The positive
pressure exerted by the feed pumps or other mechanical means pro-
vides the pressure differential which is the principal driving
force.
A typical pressure filtration unit consists of a number of plates
or trays which are held rigidly in a frame to ensure alignment
and which are pressed together between a fixed end and a travel-
ing end. On the surface of each plate is mounted a filter made
of cloth or a synthetic fiber. The feett stream is pumped into
the unit and passes through holes in the trays along the length
of the press until the cavities or chambers between the trays are
completely filled. The solids are then entrapped, and a cake
begins to form on the surface of the filter material. The water
passes through the fibers, and the solids are retained.
At the bottom of the trays are drainage ports. The filtrate is
collected and discharged to a common drain. As the filter medium
becomes coated with sludge, the flow of filtrate through the
filter drops sharply, indicating that the capacity of the filter
has been exhausted. The unit must then be cleaned of the sludge.
After the cleaning or replacement of the filter media, the unit
is again ready for operation.
Application and Performance. Pressure filtration may be used in
copper forming for sludge dewatering and also for direct removal
of precipitated and other suspended solids from wastewater.
Because dewatering is such a common operation in treatment sys-
tems, pressure filtration is a technique which can be found in
many industries concerned with removing solids from their waste
stream.
241
-------
In a typical pressure filter, chemically preconditioned sludge
detained in the unit for one to three hours under pressures vary-
ing from 5 to 13 atmospheres exhibited a final dry solids content
between 25 and 50 percent. i
i
Advantages and Limitations. The pressures which may be applied
to a sludge for removal of water by filter presses that are
currently available range from 5 to 13 atmospheres. As a result
pressure filtration may reduce the amount of chemical pretreat-
ment required for sludge dewatering. Sludge retained in the form
of the filter cake has a higher percentage of solids than that
from a centrifuge or vacuum filter. Thus, it can be easily
accommodated by materials handling systems.
As a primary solids removal technique, pressure filtration
requires less space than clarification and is well suited to
streams with high solids loadings. The sludge produced may be
disposed of without further dewatering. The amount of sludge is
increased by the use of filter precoat materials (usually dia-
tomaceous earth). Also, cloth pressure filters often do not
achieve as high a degree of effluent clarification as clarifiers
or granular media filters. ,
j
Two disadvantages associated with pressure filtration in the past
have been the short life of the filtjer cloths and lack of auto-
mation. New synthetic fibers have largely offset the first of
these problems. Also, units with automatic feeding and pressing
cycles are now available. s
|
For larger operations, the relatively high space requirements, as
compared to those of a centrifuge, could be prohibitive in some
situations.
i
Operational Factors. Reliability: With proper -pretreatment,
design, and control, pressure filtration is a highly dependable
system. :
Maintainability: Maintenance consists of periodic cleaning or
replacement of the filter media, drainage grids, drainage piping,
filter pans, and other parts of the system. If the removal of
the sludge cake is not automated, additional time is required for
this operation. :
Solid Waste Aspects: Because it is generally drier than other
types of sludges, the filter sludge cake can be handled with
relative ease. The accumulated sludge may be disposed by any of
the accepted procedures depending on its chemical composition.
The levels of toxic metals present in sludge from treating
aluminum forming wastewater necessitate proper disposal.
242
-------
Demonstration Status. Pressure filtration is a commonly used
technology in many commercial applications. No copper forming
plants use pressure filtration for sludge dewatering.
Settling
Settling is a process which removes solid particles from a liquid
matrix by gravitational force. This is done by reducing the
velocity of the feed stream in a large volume tank or lagoon so
that gravitational settling can occur. Figure VII-7 shows two
typical settling devices.
Settling is often preceded by chemical precipitation which
converts dissolved pollutants to solid form and by coagulation
which enhances settling by coagulating suspended precipitates
into larger, faster settling particles.
If no chemical pretreatment is used, the wastewater is fed into a
tank or lagoon where it loses velocity and the suspended solids
are allowed to settle out. Long retention times are generally
required. Accumulated sludge can be collected either periodi-
cally or continuously and either manually or mechanically.
Simple settling, however, may require excessively large catch-
ments, and long retention times (days as compared with hours) to
achieve high removal efficiencies. Because of this, addition of
settling aids such as alum or polymeric flocculants is often
economically attractive.
In practice, chemical precipitation often precedes settling, and
inorganic coagulants or polyelectrolytic flocculants are usually
added as well. Common coagulants include sodium sulfate, sodium
aluminate, ferrous or ferric sulfate, and ferric chloride.
Organic polyelectrolytes vary in structure, but all usually form
larger floe particles than coagulants used alone.
Following this pretreatment, the wastewater can be fed into a
holding tank or lagoon for settling, but is more often piped into
a clarifier for the same purpose. A clarifier reduces space
requirements, reduces retention time, and increases solids
removal efficiency. Conventional clarifiers generally consist of
a circular or rectangular tank with a. mechanical sludge collect-
ing device or with a sloping funnel-shaped bottom designed for
sludge collection. In advanced settling devices, inclined
plates, slanted tubes, or a lamellar network may be included
within the clarifier tank in order to increase the effective
settling area, increasing capacity. A fraction of the sludge
stream is often recirculated to the inlet, promoting formation of
a denser sludge.
243
-------
Application and Performance. Settling and clarification are used
in the copper forming category to remove precipitated metals.
Settling can be used to remove most suspended solids in a partic-
ular waste stream; thus it is used extensively by many different
industrial waste treatment facilities. Because most metal ion
pollutants are readily converted to solid metal hydroxide precip-
itates, settling is of particular use in those industries associ-
ated with metal production, metal finishing, metal working, and
any other industry with high concentrations of metal ions in
their wastewaters. In addition to toxic medals, suitably pre-
cipitated materials effectively removed by settling include
aluminum, iron, manganese, cobalt, antimony, beryllium,
molybdenum, fluoride, phosphate, and many others.
A properly^operated settling system can efficiently remove sus-
pended solids, precipitated metal hydroxides, and other impuri-
ties from wastewater. The performance of the process depends on
a variety of factors, including the density and particle size of
the solids, the effective charge on the suspended particles, and
the types of chemicals used in pretreatment. The site of floccu-
lant or coagulant addition also may significantly influence the
effectiveness of clarification. If the flocculant is subjected
to too much mixing before entering the clarifier, the complexes
may be sheared and the settling effectiveness diminished. At the
same time, the flocculant must have sufficient mixing and reac-
tion time in order for effective set-up and settling to occur.
Plant personel have observed that the line pr trough leading into
the clarifier is often the most efficient site for flocculant
addition. The performance of simple settling is a function of
the retention time, particle size and density, and the surface
area of the basin.
The data displayed in Table VII-10 indicate1suspended solids
removal efficiencies in settling systems.
The mean effluent TSS concentration obtained by the plants shown
in Table VII-10 is 10.1 mg/1. Influent concentrations averaged
838 mg/1. The maximum effluent TSS value reported is 2,3 mg/1.
These plants all use alkaline pH adjustment to precipitate metal
hydroxides, and most add a coagulant or flocculant prior to
settling.
|
Advantages and Limitations. The major advantage of simple set-
tling is its simplicity as demonstrated by the gravitational
settling of solid particular waste in a holding tank or lagoon.
The major problem with simple settling is the long retention time
necessary to achieve an acceptable effluent, especially if the
specific gravity of the suspended matter is close to that of
water. Some materials cannot be effectively removed by simple
settling alone.
244
-------
Settling performed in a clarifier is effective in removing slow-.
settling suspended matter in a shorter time and in less space
than a simple settling system. Also, effluent quality is often
better from a clarifier. The cost of installing and maintaining
a clarifier; however, is substantially greater than the costs
associated with simple settling.
Inclined plate, slant tube, and lamellar settlers have even
higher removal efficiencies than conventional clarifiers., and
greater capacities per unit area are possible. Installed costs
for these advanced clarification systems are^claimed to be one
half the cost of conventional systems of similar capacity.
Operational Factors. Reliability: Settling can be a highly
reliable technology for removing suspended solids. Sufficient
retention time and regular sludge removal are important factors
affecting the reliability of all settling systems. Proper con-
trol of pH adjustment, chemical precipitation, and coagulant or
flocculant addition are additional factors affecting settling
efficiencies in systems (frequently clarifiers) where these
methods are used.
Those advanced settlers using slanted tubes, inclined plates, or
a lamellar network may require prescreening of the waste in order
to eliminate any fibrous materials which could potentially clog
the system. Some installations are especially vulnerable to
shock loadings, as by storm water runoff, but proper system
design will prevent this.
Maintainability: When clarifiers or other advanced settling
devices are used, the associated system utilized for chemical
pretreatment and sludge dragout must be maintained on a regular
basis. Routine maintenance of mechanical parts is also neces-
sary. Lagoons require little maintenance other than periodic
sludge removal.
Demonstration Status
Settling represents the typical method of solids removal and is
employed extensively in industrial waste treatment. The advanced
clarifiers are just beginning to appear in significant numbers in
commercial applications. Thirty-six copper forming plants use
sedimentation or clarification.
Skimming
Pollutants with a specific gravity less than water will often
float unassisted to the surface of the wastewater. Skimming ^
removes these floating wastes. Skimming normally takes place in
a tank designed to allow the floating material to rise and remain
245
-------
I
on the surface, while the liquid flows to an outlet located below
the floating layer. Skimming devices are therefore suited to the
removal of non-emulsified oils from raw waste streams. Common
skxmming mechanisms include the rotating drum type, which picks
up oil from the surface of the water as it rotates. A doctor
blade scrapes oil from the drum and collects it in a trough for
disposal or reuse. The water portion is allowed to flow under
the rotating drum. Occasionally, an underflow baffle is
installed after the drum; this has the advantage of retaining any
floating oil which escapes the drum skimmer. The belt type
skimmer is pulled vertically through the water, collecting oil
which is scraped off from the surface and collected in a drum.
Gravity separators (Figure VII-8), such as the API type, utilize
overflow and underflow baffles to skim a floating oil layer from
the surface of the wastewater. An overflow-underflow baffle
allows a small amount of wastewater (the oil portion) to flow
over into a trough for disposition or reuse while the majority of
the water flows underneath the baffle. This is followed by an
?V^flow baffle> which is set at a height relative to the first
baffle such that only the oil bearing portion will flow over the
first baffle during normal plant operation. A diffusion device
such as a vertical slot baffle, aids in creating a uniform flow'
through the system and increasing oil removal efficiency.
Application and Performance. Skimming is applicable to any waste
stream containing pollutants which float to the surface. It is
commonly used to remove free oil, grease, and soaps. Skimming is
often used in conjunction with air flotation or clarification in
order to increase its effectiveness.
The removal efficiency of a skimmer is partly a function of the
retention time of the water in the tank. Larger, more buoyant
particles require less retention time than smaller particles.
Thus, the efficiency also depends on the composition of the waste
stream. The retention time required to allow phase separation
and subsequent skimming varies from 1 to 15 minutes, depending on
the wastewater characteristics.
API or other gravity-type separators tend to be more suitable for
use where the amount of surface oil flowing through the system is
continuous and substantial. Drum and belt type skimmers are
applicable to waste streams which evidence smaller amounts of
floating oil and where surges of floating oil are not a problem.
Using an API separator system in conjunction with a drum type
skimmer would be a very effective method of removing floating
contaminants from non-emulsified oily waste streams. Sampling
data shown in Table VII-11 illustrate the capabilities of the
technology with both extremely high and moderate oil influent
levels.
246
-------
This data is intended to be illustrative of the very high level
of oil and grease removals attainable in a simple two stage^oil
removal system. Based on the performance of installations in a
variety of manufacturing plants and permit requirements that are
constantly achieved, it is determined that effluent oil levels
may be reliably reduced below 10 mg/1 with moderate influent
concentrations. Very high concentrations of oil such as the 22
percent shown in Table VII-11 may require two step treatment to
achieve this level.
Skimming which removes oil may also be used to remove base levels
of organics. Plant sampling data show that many organic com-
pounds tend to be removed in standard wastewater treatment equip-
ment. Oil separation not only removes oil but also organics that
are more soluble in oil than in water. Clarification removes
organic solids directly and probably removes dissolved organics
by adsorption on inorganic solids.
The source of these organic pollutants is not always known with
certainty, although in metal forming operations they seem to
derive mainly from various process lubricants. They are also
sometimes present in the plant water supply, as additives to
proprietary formulations of cleaners* or due to leaching from
plastic liners and other materials.
High molecular weight organics in particular are much more solu-
ble in organic solvents than in water. Thus they are much more
concentrated in the oil phase that is skimmed than in the waste-
water. The ratio of solubilities of a compound in oil and water
phases is called the partition coefficient. The logarithm of the
partition coefficients for 15 polynuclear aromatic hydrocarbon
(PAH) compounds in octanol and water are:
PAH Priority Pollutant
1. Acenaphthene
30. Fluoranthene
72. Benzo(a)anthracene
73. Benzo(a)pyrene
74. 3,4-Benzofluoranthene
75. Benzo(k)fluoranthene
76. Chrysene
77. Acenaphthylene
78. A.nthracene
79. Benzo(ghi)perylene
80. Fluorene
81. Phenanthrene
82. Dibenzo(a,h)anthracene
83. Indeno(l,2,3,cd)pyrene
84. Pyrene
Log Octanol/Water
Partition Coefficient
4.33
5.33
5.61
6.04
6.57
6.84
5.61
4.07
4.45
7.23
4.18
4.46
.97
.66
5,
7
5.32
247
-------
Plant sampling data show that many organic:compounds tend to be
removed in standard wastewater treatment equipment. Oil separa-
tion not only removes oil but also organics that are more soluble
in oil than in water. Clarification removes organic solids
directly and probably removes dissolved organics by adsorption on
inorganic solids.
|
Figure VII-9 shows the relationship between the concentrations of
total toxic organics and oil and grease in wastewater samples
from copper forming plants. It can be seen that if a daily
maximum oil and grease concentration of 20 mg/1 is achieved, the
concentration of total toxic organics is expected to be below 0.5
mg/1. This conclusion is also supported by data from copper
forming plants which practice oil skimming on wastewaters which
contain toxic organics as well as oil and grease. Data from
three days of sampling at two copper forming plants which prac-
tice oil skimming and achieve effluent oil and grease concentra-
tions of 20 mg/1 or less are presented in Table VII-12. It can
be seen that the concentration of total toxic organics in these
effluent samples never exceeds 0.31 mg/1.
I
The unit operation most applicable to removal of trace toxic
organics is adsorption, and chemical oxidation is another possi-
bility. Biological degradation is not generally applicable
because the organics are not present in sufficient concentration
to sustain a biomass and because most of the organics are
resistant to biodegradation.
Advantages and Limitations. Skimming as a pretreatment is effec-
tive in removing naturally floating waste material. It also
improves the performance of subsequent downstream treatments.
Many pollutants, particularly dispersed or emulsified oil, will
not float "naturally" but require additional treatments. There-
fore, skimming alone may not remove all the pollutants capable of
being removed by air flotation or other more sophisticated tech-
nologies .
Operational Factors. Reliability: Because of its simplicity,
skimming is a very reliable technique.
Maintainability: The skimming mechanism requires periodic
lubrication, adjustment, and replacement of worn parts.
Solid Waste Aspects: The collected layer of debris must be
disposed of by contractor removal, landfill, or incineration.
Because relatively large quantities of water are present in the
collected wastes, incineration is not always a viable disposal
method. !
Demonstration Status. Skimming is a common operation utilized
extensively by industrial waste treatment systems. It is
presently used at 10 copper forming plants.j
248
-------
Chemical Emulsion Breaking
Chemical treatment is often used to break stable oil-in-water
(0-W) emulsions. An 0-W emuls'ion consists of oil dispersed in
water, stabilized by electrical charges and emulsifying agents.
A stable emulsion will not separate or break down without some
form of treatment.
Once an emulsion is broken, the difference in specific gravities
allows the oil to float to the surface of the water. Solids^usu-
ally form a layer between the oil and water, since some oil is
retained ,in the solids. The longer the retention time, the more
complete and distinct the separation between the oil, solids, and
water will be. Often other methods of gravity differential
separation, such as air flotation or rotational separation (e.g.,
centrifugation), are used to enhance and speed separation. ^A
schematic flow diagram of one type of application is shown in
Figure VII-10.
The major equipment required for chemical emulsion breaking
includes: reaction chambers with agitators, chemical storage
tanks, chemical feed systems, pumps, and piping.
Emulsifiers may be used in the plant: to aid in stabilizing or
forming emulsions. Emulsifiers are surface-active agents which
alter the characteristics of the oil and water interface. These
sufactants have rather long polar molecules. One end of the
molec-ale is particularly soluble in water (e.g., carboxyl, sul-
fate, hydroxyl, or sulfonate groups) and the other end is readily
soluble in oils (an organic group which varies greatly with the
different surfactant type). Thus, the surfactant emulsifies or
suspends the organic material (oil) in water. Emulsifiers also
lower the surface tension of the 0-W emulsion as a result of
solvation and ionic complexing. These emulsions must be
destabilized in the treatment system.
Application and Performance. Emulsion breaking is applicable to
waste streams containing emulsified oils or lubricants such as
rolling and drawing emulsions.
Treatment of spent 0-W emulsions involves the use of chemicals to
break the emulsion followed by gravity differential separation.
Factors to be considered for breaking emulsions are type of chem-
icals, dosage and sequence of addition, pH, mechanical shear and
agitation, heat, and retention time.
Chemicals, e.g., polymers, alum, ferric chloride, and organic
emulsion breakers, break emulsions by neutralizing repulsive
charges between particles, precipitating or salting out emul-
sifying agents, or altering the interfacial film between the
249
-------
oil and water so it is readily broken. Reactive cations, e.g.,
H(+l), Al(+3), Fe(+3), and cationic polymers, are particularly
effective in breaking dilute 0-W emulsions. Once the charges
have been neutralized or the ihterfacial film broken, the small
oil droplets and suspended solids wil be adsorbed on the surface
of the floe that is formed, or break out and float to the top.
Various types of emulsion-breaking chemicals are used for the
various types of oils.
If more than one chemical is required, the sequence of addition
can make quite a difference in both breaking efficiency and
chemical dosages.
i
pH plays an important role in emulsion breaking, especially if
cationic inorganic chemicals, such as alum,; are used as coagu-
lants. A depressed pH in the range of 2 to 4 keeps the aluminum
ion in its most positive state where it can function most effec-
tively for charge neutralization. After some of the oil is
broken free and skimmed, raising the pH into the 6 to 8 range
with lime or caustic will cause the aluminum to hydrolyze and
precipitate as aluminum hydroxide. This floe entraps or adsorbs
destabilized oil droplets which can then be separated from the
water phase. Cationic polymers can break emulsions over a wider
pH range and thus avoid acid corrosion and the additional sludge
generated from neutralization; however, an inorganic flocculant
is usually required to supplement the polymer emulsion breaker's
adsorptive properties.
Mixing is important in breaking 0-W emulsions. Proper chemical
feed and dispersion is required for effective results. Mixing
also causes collisions which help break the emulsion, and sub-
sequently helps to agglomerate droplets.
In all emulsions, the mix of two immiscible liquids has a spe-
cific gravity very close to that of water. Heating lowers the
viscosity and increases the apparent specific gravity differen-
tial between oil and water. Heating also increases the frequency
of droplet collisions, which helps to rupture the interfacial
film.
j
Oil and grease and suspended solids performance data are shown in
Table VII-13. Data were obtained from sampling at operating
plants and a review of the current literature. This type of
treatment is proven to be reliable and is considered the current
state-of-the-art for copper forming emulsified oily wastewaters.
Advantages and Limitations. Advantages gained from the use of
chemicals for breaking 0-W emulsions are the high removal effi-
ciency potential and the possibility of reclaiming the oily
waste. Disadvantages are corrosion problems associated with
250
-------
acid-alum systems, skilled operator requirements for batch treat-
ment, chemical sludges produced, and poor cost-effectiveness for
low oil concentrations.
Operational Factors. Reliability: Chemical emulsion breaking is
a very reliable process. The main control parameters, pH and
temperature, are fairly easy to control.
Maintainability: Maintenance is required on pumps, motors, and
valves, as well as periodic cleaning of the treatment tank to
remove any accumulated solids. Energy use is limited to mixers
and pump s.
Solid Waste Aspects: The surface oil and oily sludge produced
are usually hauled away by a licensed contractor. If the recov-
ered oil has a sufficiently low percentage of water, it may be
burned for its fuel value or processed and reused.
Demonstration Status. Sixteen plants in the aluminum forming
category currently break emulsions with chemicals. Eight plants
chemically break spent rolling oil emulsions with chemicals, one
plant breaks its rolling and drawing emulsions, one plant breaks
its rolling oils and degreasing solvent, one plant breaks its
direct chill casting contact cooling water, scrubber liquor, and
sawing oil, and one plant breaks its direct chill casting contact
cooling water and extrusion press heat treatment contact cooling
water. No plants in the copper forming industry currently use
chemical emulsion breaking.
Thermal Emulsion Breaking
Dispersed oil droplets in a spent emulsion can be destabilized by
the application of heat to the waste. One type of technology
commonly used, in the metals and mechanical products industries is
the evaporation-decantation-condensation process, also called
thermal emulsion breaking (TEB), which separates the emulsion
waste into distilled water, oils and other floating materials,
and sludge. Raw waste is fed to a main reaction chamber. Warm
air is passed over a large revolving drum which is partially sub-
merged in the waste. Some water evaporates from the surface of
the drum and is carried upward through a filter and a condensing
unit. The condensed water is discharged or reused as process
makeup, while the air is reheated and returned to the evaporation
stage. As the water evaporates in the main chamber, oil concen-
tration increases. This enhances agglomeration and gravity sepa-
ration of oils. The separated oils and other floating materials
flow over a weir into a decanting chamber. A rotating drum
skimmer picks up oil from the surface of the decanting chamber
and discharges it for possible reprocessing or contractor
removal. Meanwhile, oily water is being drawn from the bottom of
251
-------
the decanting chamber, reheated, and sent back into the main con-
veyorized chamber. Solids which settle out in the main chamber
are removed by a conveyor belt. This conveyor belt, called a
flight scraper, moves slowly so as not to interfere with the
settling of suspended solids.
Application and Performance. Thermal emulsion breaking technol-
ogy can be applied to the treatment of spent emulsions in the
copper forming category.
The performance of a thermal emulsion breaker is dependent
primarily on the characteristics of the raw waste and proper
maintenance and functioning of the process components. Some
emulsions may contain volatile compounds which could escape with
the distilled water. In systems where the water is recycled back
to process; however, this problem is essentially elminated.
Experience in at least two copper forming plants has shown that
trace organics or other contaminants found (in the condensed water
will not adversely affect the lubricants when this water is used
for process emulsions. In one copper forming plant, typical oil
and grease level in the condensed water was 1 mg/1.
]
Advantages and Limitations. Advantages of the thermal emulsion
breaking process include high percentages of oil removal (at
least 99 percent in most cases), the separation of floating oil
from settleable sludge solids, and the production of distilled
water which is available for process reuse. In addition, no
chemicals are required and the operation is automated, factors
which reduce operating costs. Disadvantages of the process are
the energy requirement for water evaporation and, if intermit-
tently operated, the necessary installation of a large storage
tank.
Operational Factors. Reliability: Thermal emulsion breaking is
a very reliable process for the treatment of emulsified oil
wastes.
Maintainability: The thermal emulsion breaking process requires
minimal routine maintenance of the process components, and peri-
odic disposal of the sludge and oil.
i
Solid Waste Aspects: The thermal emulsion breaking process
generates sludge which must be properly disposed of.
Demonstration Status. Thermal emulsion breaking is used in
metals and mechanical products industries. ;It is a proven method
of effectively treating emulsified wastes. Six copper forming
plants currently use thermal emulsion breaking.
252
-------
MAJOR TECHNOLOGY EFFECTIVENESS
The performance of individual treatment technologies was pre-
sented above. Performance of operating systems is discussed
here. Two different systems are considerred: LSeS (hydroxide
precipitation and sedimentation or lime and settle) and LSScF
(hydroxide precipitation, sedimentation, and filtration or lime,
settle, and filter). Subsequently, an analysis of effectiveness
of such systems is made to develop one-day maximum and ten-day
and thirty-day average concentration levels to be used in regu-
lating pollutants. Evaluation of the L&S and the LS&F systems is
carried out on the assumption that chemical reduction of chro-
mium, cyanide precipitation, oil skimming, and emulsion breaking
are installed and operating properly where appropriate.
LS»S Performance - Combined Metals Data Base
Before proposal, chemical analysis data were collected of raw
waste (treatment influent) and treated waste (treatment effluent)
from 55 plants (126 data days) sampled by EPA (or its contractor)
using EPA sampling and chemical analysis protocols. These data
are the data base for determining the effectiveness of L&S tech-
nology. Each of these plants belongs to at least one of the
following industry categories: aluminum forming, battery
manufacturing, coil coating, copper forming, electroplating and
porcelain enameling. All of the plants employ pH adjustment and
hydroxide precipitation using lime or caustic, followed by
settling (tank, lagoon or clarifier) for solids removal. Most
also add a coagulant or flocculant prior to solids removal.
An analysis of this data was presented in the development docu-
ments for the proposed regulations for coil coating and porcelain
enameling (January 1981). In response to the proposal, some
commenters claimed that it was inappropriate to use data from
some categories for regulation of other categories. In response
to these comments, the Agency reanalyzed the data. An analysis
of variance was applied to the data for the 126 days of sampling
to test the hypothesis of homogeneous plant mean raw and treated
effluent levels across categories by pollutant. This analysis is
described in the report, "A Statistical Analysis of the Combined
Metals Industries Effluent Data" which is in the administrative
record supporting this rulemaking. The main conclusion drawn
from the analysis of variance is that, with the exception of
electroplating, the categories are generally homogeneous with
regard to mean pollutant concentrations in both raw and treated
effluent. That is, when data from electroplating facilities are
included in the analysis, the hypothesis of homogeneity across
categories is rejected. When the electroplating data are removed
from the analysis the conclusion changes substantially and the
hypothesis of homogeneity across categories is not rejected. On
253
-------
the basis of this analysis, the electroplating data were removed
from the data base used to determine limitations. Cases that
appeared to be marginally different were not unexpected (such as
copper in copper forming and lead in lead battery manufacturing)
and were accommodated in developing limitations by using the
larger values obtained from the marginally different category to
characterize the entire data set.
The statistical analysis provides support for the technical engi-
neering judgement that electroplating wastewaters are different
from most metal processing wastewater. These differences may be
further explained by differences in the constituents and relative
amounts of pollutants in the raw wastewaters. Therefore, the
wastewater data derived from plants that only electroplate are
not used in developing limitations for the aluminum forming
category.
i
After removing the electroplating data, data from 21 plants and
52 days of sampling remained.
For the purpose of developing treatment effectiveness, certain
additional data were deleted from the data base before examina-
tion for homogeneity. These deletions were made to ensure that
the data reflect properly operated treatment systems and actual
pollutant removal. The following criteria were used in making
these deletions:
Plants where malfunctioning processes or treatment
systems at time of sampling were identified.
- Data days where pH was less than 7.0 or TSS was greater
than 50 mg/1. (This is a prima^facie indication of poor
operation.)
Data points where the raw value was too low to assure
actual pollutant removal occurred (i.e., less than 0.1
mg/1 of pollutant in raw waste).
Collectively, these selection criteria ensure that the data are
from properly operating lime and settle treatment facilities.
The remaining data are displayed graphically in Figures VII-11 to
VII-19. This common or combined metals data base provides a more
sound and usable basis for estimating treatment effectiveness and
statistical variability of lime and settle technology than the
available data from any one category.
One-Day Effluent Values
The basic assumption underlying the determination of treatment
effectiveness is that the data for a particular pollutant are
254
-------
lognormally distributed by plant. The lognormal has been found
to provide a satisfactory fit to plant effluent data in a number
of effluent guidelines categories. In, the case of the combined
metal categories data base, there are too few data from any one
plant to verify formally the lognormal assumption. ^ Thus, we
assumed measurements of each pollutant from a particular plant,
denoted by X, follow a lognormal distribution with a log mean u
and log variance 02. The mean, variance, and 99th percentile
of X are then:
mean of X - E(X) - exp ( U+ a2/?.)
variance of X = V(X) - exp(2 u+a2) [exp(a2) - 1]
99th percentile
= exp( U+ 2.33a)
where exp is e, the base of the natural logarithm. The term
lognormal is used because the logarithm of X has a normal dis-
tribution with mean u and variances2. Using the basic
assumption of log normality the actual treatment effectiveness
was determined using a lognormal distribution that, in a sense,
approximates the distribution of an average of the plants in the
data base, i.e., an "average plant" distribution. The notion of
an "average plant" distribution is not a strict statistical con-
cept but is used here to determine limits that would represent
the performance capability of an average of the plants in the
data base.
This "average plant" distribution for a particular pollutant was
developed as follows: the log mean was determined by taking the
average of all the observations for the pollutant across plants.
The log variance was determined by the pooled within plant
variance. This is the weighted average of the plant variances.
Thus, the log mean represents the average of all the data for the
pollutant and the log variance represents the average of the
plant log variances or average plant variability for the
pollutant.
The one-day effluent values were determined as follows:
Let Xj_j - the jth observation on a particular pollutant at
plant 3. where
X
I
Ji
Then
where
1 ,
total number of plants
number of observations at plant i.
In
£J
In means the natural logarithm.
255
-------
Then
where
y = log mean over all plants
I Ji
= 2 Z
i=l J-l
n — total number of observations
I :
- S Ji
and
V(y)
pooled log variance
(Ji-DSi*
2
(Ji-1)
where
— log variance at plant i
ii
j-i yx:i
s log mean at plant i. >
Thus, y and V(y) are the log mean and log variance, respectively,
of the lognormal distribution used to determine the treatment
effectiveness. The estimated mean and 99th percentile of this
distribution form the basis for the long term average and daily
maximum effluent limitations, respectively. The estimates are
mean
= exp(y)i|in(0.5V(y))
99th percentile = X.99 = exp[y + 2.3;3Vv(y)]
where *K.) is a Bessel function and exp is e, the base of the
natural logarithms (see Aitchison, J. and J. A. C. Brown, The
Lognormal Distribution, Cambridge University Press, 1963). In
cases where zeros were present in the data,, a generalized form of
the lognormal, known as the delta distribution was used (see
Aitchison and Brown, op. cit., Chapter 9).
(
For certain pollutants, this approach was modified slightly to
accommodate situations in which a category or categories stood
out as being marginally different from the others. For instance,
after excluding the electroplating data and other data that did
256
-------
not reflect pollutant removal or proper treatment, the effluent
copper data from the copper forming plants were statistically
significantly greater than the copper data from the other plants.
Thus, copper effluent values shown in Table VII-14 are based only
on the copper effluent data from the copper forming plants. That
is, the log mean for copper is the mean of the logs of all copper
values from the copper forming plants only and the log variance
is the pooled log variance of the copper forming plant data only.
In the case of cadmium, after excluding the electroplating data
and data that did not reflect removal or proper treatment, there
were insufficient data to estimate the log variance for cadmium.
The variance used to determine the values shown in Table VII-14
for cadmium was estimated by pooling the within plant variances
for all the other metals. Thus, the cadmium variability is the
average of the plant variability averaged over all the other
metals. The log mean for cadmium is the mean of the logs of the
cadmium observations only. A complete discussion of the data and
calculations for all the metals is contained in the administra-
tive record for this rulemaking.
Average Effluent Values
Average effluent values that form the basis for the monthly
limitations were developed in a manner consistent with the method
used to develop one-day treatment effectiveness in that the log-
normal distribution used for the one-day effluent values was also
used as the basis for the average values. That is, we assume a
number of consecutive measurements are drawn from the distribu-
tion of daily measurements. The approach used for the 10 mea-
surements valxies was employed previously for the electroplating
category (see "Development Document for Existing Sources
Pretreatment Standards for the Electroplating Point Source
Category," EPA 440/1-79/003, U.S. Environmental Protection .
Agency, Washington, D.C., August, 1979). That is, the distri-
bution of the average of 10 samples from a lognormal was
approximated by another lognormal distribution. Although the
approximation is not precise theoretically, there is empirical
evidence based on effluent data from a number of categories that
the lognormal is an adequate approximation for the distribution
of small samples. In the course of previous work the approxi-
mation was verified in a computer simulation study. The average
values were developed assuming independence of the observations
although no particular sampling scheme was assumed.
Ten-Sample Average:
The formulas for the 10-sample limitations were derived on the
basis of simple relationships between the mean and variance of
the distributions of the daily pollutant measurements and the
average of 10 measurements. We assume the daily concentration
257
-------
measurements for a particular pollutant, denoted by X, follow a
lognormal distribution with log mean and log variance denoted by
P and a^ respectively. Let XIQ denote the mean of 10
consecutive measurements. The following relationships then hold
assuming the daily measurements are independent:
mean of
= E(X)
variance of XIQ - V(XIQ) - V(X) * 10.
Where E(X) and V(X) are the mean and_variance of X, respectively,
defined above. We then assume that X^Q follows a lognormal
distribution with log meanuio and log standard deviation
10
mean and variance of
are then
- exp(y1() + 0.5a210)
V(X10) - exp(2v10 +
Now,
and
can ^e derived in terms of u and a2 as
+ o.51n[l
(exp(a2) -
(exp(a2 -
Therefore, U IQ and cr2^Q can be estimated using the above
relationships and the estimates of U and a;2 obtained for the
underlying lognormal distribution. The 10 sample limitation
value was determined by the estimate of the approximate 99th
percentile of the distribution of the 10 sample average given by
= exp(uio + 2.33 a10)
A
OIQ are the estimates of UIQ and
where UIQ
respectively.
30 Sample Average:
i
The average values based on 30 measurements are determined on the
basis of a statistical result known as the Central Limit Theorem.
This Theorem states that, under general and nonrestrictive
assumptions, the distribution of a sum of a number of random
variables, say n, is approximated by the normal distribution.
The approximation improves as the number of variables, n,
increases. The Theorem is quite general in that no particular
distributional form is assumed for the distribution of the
individual variables. In most applications (as in approximating
the distribution of 30-day averages) the Theorem is used to
approximate the distribution of the average of n observations of
a random variable. The result makes it possible to compute
258
-------
approximate probability statements about the average in a wide
range of cases. For instance, it is possible to compute a value
below which a specified percentage Ae.g., 99 percent) of the
averlgls of n observations are likely to fall. Most textbooks
state that 25 or 30 observations are sufficient for tne
approximation to be valid. In applying the Theorem to the _
determination of 30 day average effluent values, we approximate
the distribution of the average of 30 observations _ drawn from the
distribution of daily measurements and use the estimated yytn
percentile of this distribution. The monthly limitations based
on 10 consecutive measurements were determined using the log-
normal approximation described above because 10 measurements
were, in this case, considered too small a number for use of the
Central Limit Theorem.
30 Sample Average Calculation
The formulas for the 30 sample average were based on an applica-
tion of the Central Limit Theorem. According to the Theorem the
average of 30 observations drawn from the distribution of daily
measurements, denoted by X30, is approximately normally dis-
tributed. The mean and variance of X3o are
mean of X30 - E(X30) = E(X)
variance of X3Q = V(X3o) - V(X) * 30 .
The 30 sample average value was determined by the estimate of the
approximate 99th percentile of the distribution of the 30 sample
average given by
A
A
_
X30(.99) = E(X) + 2.33-V VA(X) * 30
where EA(X) = exp(y)ifn(0.5V(y) )
and VA(X) = exp(2y)!>n(2V(y)) - i|m { (5Z2.)
The formulas for EA(X) and V^X) are estimates of E(X) and_V(X) ,
respectively given in Aitchison, J .. and J. A. C. Brown The
T.ngLrmal Distribution, Cambridge University Press, 1963, page
45?
Application
In response to the proposed coil coating and porcelain enameling
regulations, the Agency received comments pointing out that per
mils usually required less than 30 samples to be taken during a
mon?h while> theqmonthly average used as the basis for permits and
pretreatment requirements is based on the average of 30 samples.
259
-------
In applying the treatment effectiveness values to regulations we
have considered the comments, examined the sampling frequency
SS™* 57 ^ Permits> and considered the changl in valuSs of
averages depending on the number of consecutive slmpling days in
the averages. The most common frequency of sampling requiSd in
permits is about 10 samples per month or slightly greater than
99th. P^cent iles of the dStSbSttSn of
samPlin§ days are not substantially
Percentile of the distribution's 30 day
«™n mPare^ *> ^e one-day maximum, the 10-day average is
about 80 percent of the difference between one and 30-day §
for r^nt.??nCe> the 10"1a? averaSe Provides a reasonable^ basis
1 °f
The monthly average is to be achieved in all permits and pre-
treatment standards regardless of the number of samples required
authority!7 averaged by the -permit or the pretreatment
Additional Pollutants
°f other Pol:l-utant parameters were considered with
to the performance of lime and settle treatment systems in
thS? fr°? industrial wastewater. Performance Sta for
the am* ^1S n0t reSdily availablea so data available to
the Agency in other categories has been selectively used to
determine the long-term average performance of lime and settle
technology for each pollutant. These data indicatJ Sat the
concentrations shown in Table VII-15 are reliably attaiSablS with
hydroxide precipitation and settling. The precipitation of
silver appears to be accomplished by alkaline chloride precipi-
tation and adequate chloride ions must be available for this
reaction to occur.
In establishing which data were suitable for use in Table VII-15
wI?er^aS5Sr2?r?h^eaVily w^f^: ^ th* *ature of 'the waste-
water, and (2) the range of pollutants or ; pollutant matrix in the
raw wastewater. These data have been selected from process^
™o g??er5te ^solved metals in the wastewater and which are
IvafuaS £e? °m- comPiexin§ a§ents. The pollutant matrix was
evaluated by comparing the concentrations of pollutants found in
the raw wast ewaters with the range of pollutants in the raw
wastewaters of the combined metals data set. These data are
^Sfia?±in-Ta?le? VI?-16 and VII-17 and . indicate that the?e is
sufficient similarity in the raw wastes to. logically assume
cnmSn'T^i1?7 5f ^ treated pollutant concentrations to the
combined metals data base. The available data on these added
?£» ™?S d° not1al}ow homogeneity analysis as was performed on
the combined metals data base. The data source for each added
pollutant is discussed separately.
260
t
-------
Antimony (Sb) - The achievable performance for antimony is based
on data from a battery and secondary lead plant. Both EPA sam-
pling data and recent permit data (1978 - 1982) confirm the
achievability of 0.7 mg/1 in the battery manufacturing wastewater
matrix included in the combined data set.
Arsenic (As) - The achievable performance of 0.5 mg/1 for arsenic
is based on permit data from two nonferrous metals manufacturing
plants. The untreated wastewater matrix shown in Table VII-17 is
comparable with the combined data set matrix.
Beryllium (Be) - The treatability of beryllium is transferred
from the nonferrous metals manufacturing industry. The 0.3 per-
formance is achieved at a beryllium plant with the comparable
untreated wastewater matrix shown in Table VII-17.
Mercury (Hg) - The 0.06 mg/1 treatability of mercury is based^on
data from four battery plants. The untreated wastewater matrix
at these plants was considered in the combined metals data set.
Selenium (Se) - The 0.30 mg/1 treatability of selenium is based
on recent permit data from one of the nonferrous metals manufac-
turing plants also used for antimony performance. The untreated
wastewater matrix for this plant is shown in Table VII-17.
Silver (Ag) - The treatability of silver is based on a 0.1 mg/1
treatability estimate from the inorganic chemicals industry.
Additional data supporting a treatability as stringent or more
stringent than 0.1 mg/1 is also available from seven nonferrous
metals manufacturing plants. The untreated wastewater matrix for
these plants is comparable and summarized in Table VII-17.
Thallium (Th) - The 0.50 nig/1 treatability for thallium is trans-
ferred from the inorganic chemicals industry. Although no
untreated wastewater data are available to verify comparability
with the combined metals data set plants, no other sources of
data for thallium treatability could be identified.
Aluminum (Al) - The 1.11 mg/1 treatability of aluminum is based
on the mean performance of one aluminum forming plant and one
coil coating plant. Both of the plants are from categories con-
sidered in the combined metals data set, assuring untreated
wastewater matrix comparability.
Cobalt (Go) - The 0.05 mg/1 treatability is based on nearly com-
plete removal of cobalt at a porcelain enameling plant with a
mean untreated wastewater cobalt concentration of 4.31 mg/1. In
this case, the analytical detection using aspiration techniques
for this pollutant is used as the basis of the treatability.
Porcelain enameling was considered in the combined metals data
base, assuring untreated wastewater matrix comparability.
261
-------
Fluoride (F) - The 14.5 mg/1 treat ability of fluoride is based on
the mean performance of an electronics and electrical component
manufacturing plant. The untreated wastewater matrix for this
plant shown in Table VII-17 is comparable to the combined metals
data set i
LSScF Performance
VII-18 and VI1-19 sh°w long-term data from two plants
which have well operated precipitation-settling treatment
followed by filtration. The wastewaters from both plants contain
pollutants from metals processing and finishing operations
^multi-category) . Both plants reduce hexavalent chromium before
neutralizing and precipitating metals with lime. A clarifier is
nS e?_ to rem°ve much of the solids load and a filter is used to
polish or complete removal of suspended solids. Plant A uses
pressure filtration, while Plant B uses a rapid sand filter.
i
Raw waste data was collected only occasionally at each facility
and the raw waste data is presented as an indication of the
nature of the wastewater treated. Data from Plant A was received
as a statistical summary and is presented as received. Raw
laboratory data was collected at Plant B and reviewed for spuri-
ous points and discrepancies. The method :of treating the data
base is discussed below under lime, settle, and filter treatment
effectiveness.
Table VII-20 shows long-term data for zinc and cadmium removal at
muf^j0' a Primar7 zi-nc smelter, which operates a LS&F system.
This data represents about four months (103 data days) taken
immediately before the smelter was closed. It has been arranged
similarity to Plants A and B for comparison and use.
These data are presented to demonstrate the performance of
precipitation-settling-filtration (LS&F) technology under actual
operating conditions and over a long period of time.
It should be noted that the iron content of the raw waste of
plants A and B is high while that for Plant C is low. This
results, for plants A and B, in co-precipitation of toxic metals
WJ" ?„ ,n* Precipitation using high-calcium lime for pH control
yields the results shown in Table VII-20. Plant operating per-
sonnel indicate that this chemical treatment combination (some-
times with polymer assisted coagulation) generally produces
better and more consistent metals removal than other combinations
of sacrificial metal ions and alkalis.
262
-------
The LS&F performance data presented here are based on systems
that provide polishing filtration after effective L&S treatment.
As previously shown, IAS treatment is equally applicable to
wastewaters from the five categories because of the .homogene-
ity of its raw and treated wastewaters, and other factors.
Because of the similarity of the wastewaters after L&S treatment,
the Agency believes these wastewaters are equally amenable to
treatment using polishing filters added to the L&S treatment
system. The Agency concludes the LS&F data based on porcelain
enameling and nonferrous smelting arid refining is directly
applicable to the aluminum forming, copper forming, battery
manufacturing, coil coating, and metal molding and casting
categories, as well as to the porcelain enameling and nonferrous
smelting and refining.
Analysis of Treatment System Effectiveness
Data are presented in Table VII-14 showing the mean, one day, 10-
day and 30-day values for nine pollutants examined in the LStS
metals data base. The mean variability factor for eight pollu-
tants (excluding cadmium because of the small number of data
points) was determined and is used to estimate one day, 10-day,
and 30-day values. (The variability factor is the ratio of the
value of concern to the mean: the average variability factors
are: one day maximum - 4.100; ten-day average - 1.821; and
30-day average - 1.618.) For values not calculated from the com-
mon data base as previously discussed, the mean value for pollu-
tants shown in Table VII-15 were multiplied by the variability
factors to derive the value to obtain the one, ten- and 30-day
values. These are tabulated in Table VII-21.
LSScF technology data are presented in Tables VII-18 and VII-19.
These data represent two operating plants (A and B) in which the
technology has been installed and operated for some years. Plant
A data was received as a statistical summary and is presented
without change. Plant B data was received as raw laboratory
analysis data. Discussions with plant personnel indicated that
operating experiments and changes in materials and reagents and
occasional operating errors had occurred during the data collec-
tion period. No specific information was available on those
variablss. To sort out high values probably caused by method-
ological factors from random statistical variability, or data
noise, the Plant B data were analyzed. For each of the four
pollutants (chromium, nickel, zinc., and iron), the mean and
1 standard deviation (sigma) were calculated for the entire data
set. A data day was removed from the complete data set when any
individual pollutant concentration for that day exceeded the sum
of the mean plus three sigma for that pollutant. Fifty-one data
days (from a total of about 1,300) were eliminated by this
method.
263
-------
Another approach was also used as a check on the above method of
eliminating certain high values. The minimum values of raw
wastewater concentrations from Plant B for the same four pol-
lutants were compared to the total set of Values for the corre-
sponding pollutants. Any day on which the pollutant concentra-
tion exceeded the minimum value selected from raw wastewater
concentrations for that pollutant was discarded. Forty- five days
of data were eliminated by that procedure. Forty- three days of
data in common were eliminated by either procedures. Since
common engineering practice (mean plus 3 sigma) and logic
(.treated waste should be less than raw waste) seem to coincide
the ^ data base with the 51 spurious data days eliminated is the
basis for all further analysis. Range, mean, standard deviation
and mean plus two standard deviations are shown in Tables VII-18
and VII-19 for Cr, Cu, Ni, Zn, and Fe. ;
j
The Plant B data were separated into 1979, 1978, and total data
base (six years) segments. With the statistical analysis from
Plant A for 1978 and 1979 this in effect created five data sets
in which there is some overlap between the individual years and
total data sets from Plant B. By comparing these five parts it
is apparent that they are quite similar and all appear to be from
the same family of numbers. The largest mean found among the
five data sets for each pollutant was selected as the long-term
mean for LS&F technology and is used as the LS&F mean in Table
V JLJLMuCJL •
Plant C data were used as a basis for cadmium removal performance
and as a check on the zinc values derived from plants A and B
The cadmium data is displayed in Table VII-20 and is incorporated
into Table VII-21 for LS&F. The zinc data were analyzed for com-
pliance with the one-day and 30-day values in Table VII-21- no
ZiniC ^olue/°f the 103 data P°iRts exceeded the one-day zinc value
of 1.02 mg/1. The 103 data points were separated into blocks of
JU points and averaged. Each of the three full 30-day averages
was less than the Table VII-21 value of 0.31 mg/1. Additionally,
xr or^nt C raw wa?tewater pollutant concentrations (Table
VII-20; are well within the range of raw wastewater concentra-
tions of the combined metals data base (Table VII-16) , further
supporting the conclusion that Plant C wastewater data is
compatible with similar data from plants A and B.
Concentration values for regulatory use are displayed in Table
VII-21. Mean one-day, ten-day, and 30-day values for L&S for
nine pollutants were taken from Table VII-14; the remaining L&S
values were developed using the mean values in Table VII-15 and
the mean variability factors discussed above.
264
-------
LSStF mean values for Cd, Cr, Ni, Zn, and Fe are derived from
plants A, B, and C as discussed above. One, ten, and 30-day
values are derived by applying the variability factor developed
from the pooled data base for the specific pollutant to the mean
for that pollutant. Other LSStF values are calculated using the
long-term average or mean and the appropriate variability
factors. Mean values for'LS&F for pollutants not already discus-
sed are derived by reducing the L&S mean by one-third. The one-
third reduction was established after examining the percent
reduction in concentrations going from LScS to LSStF data for Cd,
Cr, Ni, Zn, and Fe. The average reduction is 0.3338 or one-
third.
Copper levels achieved at plants A and B may be lower than gener-
ally achievable because of the high iron content and low copper
content of the raw wastewaters. Therefore, the mean concentra-
tion value achieved is not used; LSStF mean used is derived from
the L&S technology.
LScS cyanide mean levels shown in Table VII-8 are ratioed to one-
day, ten-day, and 30-day values using mean variability factors. ,
LSStF mean cyanide is calculated by applying the ratios of
removals for L&S and LSStF as discussed previously for LSStF ^ metals
limitations. The cyanide performance was arrived at by using the
average metal variability factors. The treatment method used
here is cyanide precipitation. Because cyanide precipitation is
limited by the same physical processes as the metal precipita-
tion, it is expected that the variabilities will be similar.
Therefore, the average of the metal variability factors has been
used as a basis for calculating the cyanide one-day, ten-day, and
30-day average treatment effectiveness values.
The filter performance for removing TSS as shown in Table VII-9
yields a mean effluent concentration of 2.61 mg/1 and calculates
to a ten-day average of 4.33, 30-day average of 3.36 mg/1; a one-
day maximum of 8.88. These calculated values more than amply
support the classic values of 10 and 15, respectively, which are
used for LS&F.
Although iron was reduced in some LSStF operations, some facili-
ties using that treatment introduce iron compounds to aid
settling. Therefore, the one-day, ten-day, and 30-day values for
iron at LS&F were held at the LStS level so as to not unduly
penalize the operations which use the relatively less objection-
able iron compounds to enhance removals of toxic metals.
265
-------
MINOR TECHNOLOGIES :
Several other treatment technologies were considered for possible
application in BPT or BAT. These technologies are presented here
with a full discussion for most of them. A few are described
only briefly because of limited technical development.
Carbon Adsorption ;
The use of activated carbon to remove dissolved organics from
water and wastewater is a long demonstrated technology. It is
one of the most efficient organic removal processes available.
This sorption process is reversible, allowing activated carbon to
be regenerated for reuse by the application of heat and steam or
solvent. Activated carbon has also proved to be an effective
adsorbent for many toxic metals, including mercury. Regeneration
of carbon which has adsorbed significant metals; however, may be
difficult.
The term activated carbon applies to any amorphous form of carbon
that has been specially treated to give high adsorption capaci-
ties. Typical raw materials include coal, wood, coconut shells,
petroleum base residues, and char from sewage sludge pyrolysis.
A carefully controlled process of dehydration, carbonization, and
oxidation yields a product which 4s called activated carbon.
This material has a high capacity for adsorption due primarily to
the large surface area available for adsorption, 500 to 1,500
m^/gm, resulting from a large number of internal pores. Pore
sizes generally range from 10 to 100 angstroms in radius.
Activated carbon removes contaminants from water by the process
of adsorption, or the attraction and accumulation of one sub-
stance on the surface of another. Activated carbon preferen-
tially adsorbs organic compunds over other species and, because
of this selectivity, is particularly effective in removing
organic compounds from aqueous solution.
Carbon adsorption requires preliminary treatment to remove excess
suspended solids, oils, and greases. Suspended solids in the
influent should be less than 50 mg/1 to minimize backwash
requirements; a downflow carbon bed can handle much higher levels
(up to 2,000 mg/1), but requires frequent backwashing. Backwash-
ing more than two or three times a day is not desirable; at 50
mg/1 suspended solids, one backwash will suffice. Oil and grease
should be less than about 10 mg/1. A high level of dissolved
inorganic material in the influent may cause problems with
thermal carbon reactivation (i.e., scaling and loss of activity)
unless appropriate preventive steps are taken. Such steps might
include pH control, softening, or the use of an acid wash on the
carbon prior to reactivation. ;
266
-------
Activated carbon is available in both powdered and granular form.
A flow diagram o£ activated carbon treatment and regeneration is
shown in figure VII-20. A schematic of an individual adsorption
Column is shown in Figure VIIr21. Powdered carbon is less expen-
sive per unit- weight and may have slightly higher adsorption
capacity, but it is more difficult to handle and to regenerate.
Application and Performance. Isotherm tests have indicated that
activated carbon is .very effective in adsorbing 65 percent of the
SxilwgaSi pollutant! and is reasonably effective for another
22 percent. Specifically, activated carbon is very effective in
removing 4-dlmethylphenol, fluoranthene, isophorone naphthal-
III all' phthalates, and phenanthrene. Activated carbon is
reasonably effective on 1,1,1-trichloroethane,
1,1-dichloroethane, phenol, and toluene.
Table VII-22 summarizes the treatability effectiveness for most
of the toxic organic pollutants by activated carbon as compiled
by EPA. Table VII-23 summarizes classes of organic compounds
together with samples of organics that are readily adsorbed on
carbon? Table VII-24 lists the effectiveness of activated carbon
in reaving seven toxic organic pollutants from actual manufac-
turing process wastewater streams in the nonferrouS
-------
Solid Waste Aspects: Solid waste'from this process is contami-
nated activated carbon that requires disposal. Carbon that
undergoes regeneration reduces .the solid waste problem by
reducing the frequency of carbon replacement.
* ;
Demonstration Status. Carbon adsorption systems have been demon-
strated to be practical and economical in reducing COD, BOD and
related parameters in secondary municipal and industrial waste-
waters; xn removing toxic or refractory organics from isolated
industrial wastewaters; in removing and recovering certain
organics from wastewaters; and in the removing, and sometimes
recovering, Deselected inorganic chemicals from aqueous wastes.
Carbon adsorption is a viable and economic process for organic
waste streams containing up to 1 to 5 percent of refractory or
toxic organics. Its applicability for removal of inorganics such
as metals has also been demonstrated.
Flotation
Flotation is the process of causing particles such as metal
hydroxides or oil to float to the surface of a tank where they
can be concentrated and removed. This is accomplished by releas-
ing gas bubbles which attach to the solid particles, increasing
their buoyancy and causing them to float. In principle, this
process is the opposite of sedimentation. Figure VII-22 shows
one type of flotation system. ;
Flotation is used primarily in the treatment of wastewater
streams that carry heavy loads of finely divided suspended solids
S£ in SoJ^d* havj-ng a specific gravity only slightly greater
than 1.0, which would require abnormally long sedimentation
times, may be removed in much less time by flotation.
This process may be performed in several ways: foam, dispersed
air, dissolved air, gravity, and vacuum flotation are the most
commonly used techniques. Chemical additives are often used to
enhance the performance of the flotation process.
The principal difference among types of flotation is the method
of generating the minute gas bubbles (usually air) in a suspen-
sion of water and small particles. Chemicals may be used to
improve the efficiency with any of the basic methods. The fol-
lowing paragraphs describe the different flotation techniques and
the method of bubble generation for each process.
Froth Flotation - Froth flotation is based on differences in the
physiochemical properties in various particles. Wettability and
surface properties affect the ability of the particles to attach
themselves to gas bubbles in an aqueous medium. In froth flota-
tion, air is blown through the solution containing flotation
268
-------
reagents. The particles with water repellant surfaces stick to
air bubbles as they rise and are brought to the surface. A _
mineralized froth layer, with mineral particles attached to air
bubbles, is formed. Particles of other minerals which are read-
ily wetted by water do not stick to air bubbles and remain in
suspension.
Dispersed Air Flotation - In dispersed air flotation gas bubbles
are generated by introducing the air by means of mechanical agi-
tation with impellers or by forcing air through porous media.
Dispersed air flotation is used mainly in the metallurgical
industry.
Dissolved Air Flotation - In dissolved air flotation, bubbles are
produced by releasing air from a superstaturated solution under
relatively high pressure. There are two types of contact between
the gas bubbles and particles. The first type is predominant in
the flotation of flocculated materials and involves the entrap-
ment of rising gas bubbles in the flocculated particles^as they
increase in size. The bond between the bubble and particle is
one of physical capture only. The second type of contact is one
of adhesion. Adhesion results from the intermolecular attraction
exerted at the interface between the solid particle and the gase-
ous bubble.
Vacuum Flotation - This process consists of saturating the waste-
water with air either directly in an aeration tank, or by permit-
tine air to enter on the suction of a wastewater pump. A partial
vacuum is applied, which causes the dissolved air to come out of
solution as'minute bubbles. The bubbles attach to solid parti-
cles and rise to the surface to form a scum blanket, which is
normally removed by a skimming mechanism. Grit and other heavy
solids that settle to the bottom are generally raked to_a central
sludge oump for removal. A typical vacuum flotation unit con-^
sists of a covered cylindrical tank in which a partial vacuum is
maintained. The tank is equipped with scum and sludge removal
mechanisms. The floating material is continuously swept to the
tank periphery, automatically discharged into a scum trough, and
removed from the unit by a pump also under partial vacuum.
Auxiliary equipment includes an aeration tank for saturating the
wastewater with air, a tank with a short retention time for
removal of large bubbles, vacuum pumps, and sludge pumps.
Application and Performance. Flotation is used primarily in the
treatment of wastewater streams that carry heavy loads ^of finely
divided suspended solids or oil. Solids having a specific grav-
ity only slightly greater than 1.0, which would require abnor-
mally long sedimentation times, may be removed in much less time
by flotation.
269
-------
The primary variables for flotation design are pressure, feed
solids concentration, and retention period. The suspended solids
in the^effluent decrease, and the concentration of solids in the
float increases, with increasing retention period. When the
flotation process is used primarily for clarification, a reten-
tion period of 20 to 30 minutes is adequate for separation and
concentration.
Advantages and Limitations. Some advantages of the flotation
process are the high levels of solids separation achieved in many
applications, the relatively low energy requirements, and the
adaptability to meet the treatment requirements of different
Wf5jre. tyP68 • Limitations of flotation are that it often requires
addition of chemicals to enhance process performance and that it
generates large quantities of solid waste.
Operational Factors. Reliability: Flotation systems normally
are very reliable with proper maintenance of the sludge collector
mechanism and the motors and pumps used for aeration.
Maintainability: Routine maintenance is required on the pumps
and motors. The sludge collector mechanism is subject to possi-
ble corrosion or breakage and may require periodic replacement.
Solid Waste Aspects: Chemicals are commonly used to aid the
flotation process by creating a surface or a structure that can
easily adsorb or entrap air bubbles. Inorganic chemicals, such
as the aluminum and ferric salts, and activated silica, can bind
the particulate matter together and create a structure that can
entrap air bubbles. Various organic chemicals can change the
nature of either the air-liquid interface or the solid-liquid
interface, or both. These compounds usually collect on the
interface to bring about the desired changes. The added chemi-
cals plus the particles in solution combine to form a large '
volume of sludge which must be further treated or properly
disposed. , J
Demonstration Status. Flotation is a fully developed process and
is readily available for the treatment of a wide variety of
industrial waste streams. Dissolved air flotation technology is
used by can manufacturing plants to remove oil and grease in the
wastewater from can wash lines. It is not currently used to
treat copper forming wastewaters.
Centrifugation
I
Centrifugation is the application of centrifugal force to sepa-
rate solids and liquids in a liquid-solid mixture or to effect
concentration of the solids. The application of centrifugal
force is effective because of the density differential normally
270
-------
found between the insoluble solids and the liquid in which they^
are contained. As a waste treatment procedure, centrifugation in-
most often applied to dewatering of sludges. One type of centri-
fuge is shown in Figure VII-23.
There are three common types of centrifuges: the disc, basket,
and conveyor type. All three operate by removing solids under
the influence of centrifugal force. The fundamental difference
between the three types is the method by which solids are col-
lected in and discharged from the bowl.
In the disc centrifuge, the sludge feed is distributed between
narrow channels that are present as spaces between stacked .con-
ical discs. Suspended particles are collected and discharged
continuously through small orifices in the bowl wall. The clar-
ified effluent is discharged through an overflow weir.
A second type of centrifuge which is useful in dewatering sludges
is the basket centrifuge. In this type of centrifuge, sludge
feed is introduced at the bottom o£ the basket, and solids col-
lect at the bowl wall while clarified effluent overflows the lip
ring at the top. Since the basket centrifuge does not have pro-
vision for continuous discharge of collected cake, operation^
requires interruption of the feed for cake discharge for a minute
or two in a 10 to 30 minute overall cycle.
The third type of centrifuge commonly used in sludge dewatering
is the conveyor type. Sludge is fed through a stationary feed
pipe into a rotating bowl in which the solids are settled out
against the bowl wall by centrifugal force. From the bowl wall,
they are moved by a screw to the end of the machine, at which
point they are discharged. The liquid effluent is discharged
through ports after passing the length of the bowl under cen-
trifugal force.
Application and Performance. Virtually all industrial^waste
treatment systems producing sludge can use centrifugation to
dewater it. Centrifugation is currently being used by a wide
range of industrial concerns.
The performance of sludge dewatering by centrifugation depends on
the feed rate, the rotational velocity of the drum, and the
sludge composition and concentration. Assuming proper design and
operation, the solids content of the sludge can be increased to
20 to 35 percent.
Advantages and Limitations. Sludge dewatering centrifuges have
minimal space requirements and show a high degree of effluent
clarification. The operation is simple, clean, and relatively
271
-------
inexpensive. The area required for a centrifuge system instal-
lation is less than that required for a filter system or sludge
drying bed of equal capacity, and the initial cost is lower.
Centrifuges have a high power cost that partially offsets the low
initial cost. Special consideration must also be given to pro-
viding sturdy foundations and soundproofing because of the vibra-
tion and noise that result from centrifuge operation. Adequate
electrical power must also be provided since large motors are
required. The major difficulty encountered in the operation of
centrifuges has been the disposal of the concentrate which is
relatively high in suspended, non-settling solids.
Operational Factors. Reliability: Centrifugation is highly
reliable with proper control of factors such as sludge feed con-
sistency, and temperature. Pretreatment such as grit removal and
coagulant addition may be necessary, depending on the composition
of the sludge and on the type of centrifuge employed.
Maintainability: Maintenance consists of periodic lubrication
cleaning, and inspection. The frequency and degree of inspection
required varies depending on the type of sludge solids being
dewatered and the maintenance service conditions. If the sludge
is abrasive, it is recommended that the first inspection of the
rotating assembly be made after appr9ximately 1,000 hours of
operation. If the sludge is not abrasive or corrosive, then the
initial inspection might be delayed. Centrifuges not equipped
with a continuous sludge discharge system require periodic
shutdowns for manual sludge cake removal.
Solid Waste Aspects: Sludge dewatered in the centrifugation pro-
cess may be disposed of by landfill. The clarified effluent
Ccentrate), if high in dissolved or suspended solids, may require
further treatment prior to discharge. !
i
Demonstration Status. Centrifugation is currently used in a
great many commercial applications to dewater sludge. Work is
underway to improve the efficiency, increase the capacity and
lower the costs associated with centrifugation.
Coalescing
i
The basic principle of coalescence involves the preferential
wetting of a coalescing medium by oil droplets which accumulate
on the medium and then rise to the surface of the solution as
they combine to form larger particles. The most important
requirements for coalescing media are wettability for oil and
large surface area. Monofilament line is sometimes used as a
coalescing medium.
272
-------
Coalescing stages may be integrated with a wide variety of grav-
ity oil separation devices, and some systems may incorporate
several coalescing stages. In general, a preliminary oil skim-
ming step is desirable to avoid overloading the coalescer.
One commercially marketed system for oily waste treatment com-
bines coalescing with inclined plant separation and filtration.
In this system, the oily wastes flow into an inclined plate
settler. This unit consists of a stack of inclined baffle plates
in a cylindrical container with an oil collection chamber at the
top. The oil droplets rise and impinge upon the undersides of
the plants. They then migrate upward to a guide rib that directs
the oil to the oil collection chamber, from which oil is dis-
charged for reuse or disposal.
The oily water continues on through another cylinder containing
replaceable filter cartridges that remove suspended particles^
from the waste. From there the wastewater enters a final cylin-
der in which the coalescing material is housed. As the oily
water passes through the many small, irregular, continuous
passages in the coalescing material, the oil droplets coalesce
and rise to an oil collection chamber.
Application and Performance. Coalescing is used to treat oily
wastes that do not separate readily in simple gravity systems.
The three stage system described above has achieved effluent
concentrations of 10 to 15 mg/1 oil and grease from raw waste
concentrations of 1,000 mg/1 or more.
Advantages and Limitations. Coalescing allows removal of oil
droplets too finely dispersed for conventional gravity
separation-skimming technology. It also can significantly reduce
the residence times (and therefore separator volumes) required to
achieve separation of oil from some wastes. Because of its sim-
plicity, coalescing provides generally high reliability and low
capital and operating costs. Coalescing is not generally^effec-
tive in removing soluble or chemically stabilized emulsified
oils. To avoid plugging, coalescers must be protected by pre-
treatment from the very high concentrations of free oil and
grease and suspended solids. Frequent replacement of prefilters
may be necessary when raw waste oil concentrations are high.
Operational Factors. Reliability: Coalescing is inherently ,
highly reliable since there are no moving parts and the coalesc-
ing substrate (monofilament, etc.) is inert in the process and
therefore not subject to frequent regeneration or replacement
requirements. Large loads or inadequate preliminary^treatment;
however, may result in plugging or bypass of coalescing stages.
273
-------
Maintainability: Maintenance requirements are generally limited
to replacement of the coalescing medium on an infrequent basis.
Solid Waste Aspects:
this process.
No appreciable solid waste is generated by
Demonstration Status. Coalescing has been fully demonstrated in
industries generating oily wastewater. A few are known to be in
use at copper forming plants.
Cyanide Oxidation by Chlorine
Cyanide oxidation using chlorine is widely used in industrial
waste treatment to oxidize cyanide. Chlorine can be utilized in
either the elemental or hypochlorite forms. This classic proced-
ure can be illustrated by the following two step chemical reac-
tion:
NaCN + 2NaOH
2. 3C12 + 6NaOH + 2NaCNO
2NaCl
2NaHC03
6NaCl + 2H20
The reaction presented as equation (2) for the oxidation of cya-
nate is the final step in the oxidation of cyanide. A complete
system for the alkaline chlorination of cyanide is shown in
Figure VII-24.
The alkaline chlorination process oxidizes cyanides to carbon
dioxide and nitrogen. The equipment often consists of an equali-
zation tank followed by two reaction tanks, although the reaction
can be carried out in a single tank. Each tank has an electronic
recorder-controller to maintain required conditions with respect
to pH^and oxidation reduction potential (ORP) . In the first
reaction tank, conditions are adjusted to oxidize cyanides to
cyanates. To effect the reaction, chlorine is metered to the
reaction tank as required to maintain the ORP in the range of 350
to 400 millivolts, and 50 percent aqueous caustic soda is added
to maintain a pH range of 9.5 to 10. In the second reaction
tank, conditions are maintained to oxidize cyanate to carbon
dioxide and nitrogen. The desirable ORP and pH for this reaction
are 600 millivolts and a pH of 8.0. Each of the reaction tanks
is equipped with a propeller agitator designed to provide approx-
imately one turnover per minute. Treatment by the batch process
is accomplished by using two tanks, one for collection of water
over a specified time period, and one tank for the treatment of
an accumulated batch. If dumps of concentrated wastes are fre-
quent, another tank may be required to equalize the flow to the
treatment tank. When the holding tank is full, the liquid is
transferred to the reaction tank for treatment. After treatment,
the supernatant is discharged and the sludges are collected for
removal and ultimate disposal.
274
-------
Application and Performance. The oxidation of cyanide waste by
chlorine is a classic process and is found in most industrial
plants using cyanide. This process is capable of achieving
effluent levels of free cyanide that are nondetectable. The
process is potentially applicable to aluminum forming facilities
where cyanide is a component in conversion coating formulations
or is added as a corrosion inhibitor in heat treatment opera-
tions.
Advantages and Limitations. Some advantages of chlorine•oxidaton
for handling process effluents are operation at ambient tempera-
ture, suitability for automatic control, and low cost. Disadvan-
tages include the need for careful pH control, possible chemical
interference in the treatment of mixed wastes, and the potential
hazard of storing and handling chlorine gas. If organic com-
pounds are present, toxic chlorinated organics may be generated.
Alkaline chlorination is not effective in treating metallocyanide
complexes, such as the ferrocyanide.
Operational Factors. Reliability: Chlorine oxidation is highly
reliable with proper monitoring and control, and proper pretreat-
ment to control interfering substances.
Maintainability: Maintenance consists of periodic removal of
sludge and recalibration of instruments.
Solid Waste Aspects: There is no solid waste problem associated
with chlorine oxidation.
Demonstration Status. The oxidation of cyanide wastes by chlo-
rine is a widely used process in plants using cyanide in cleaning
and metal processing baths.
Cyanide Oxidation by Ozone .
Ozone is a highly reactive oxidizing agent which is approximately
10 times more soluble than oxygen on a weight basis in water.
Ozone may be produced by several methods, but the silent electri-
cal discharge method is predominant in the field. The silent
electrical discharge process produces ozone by passing oxygen or
air between electrodes separated by an insulating material. A
complete ozonation system is represented in Figure VII-25.
Application and Performance. Ozonation has been applied commer-
cially to oxidize cyanides, phenolic chemicals, and organometal
complexes. Its applicability to photographic wastewaters has
been studied in the laboratory with good results. Ozone is used
in industrial waste treatment primarily to oxidize cyanide to
cyanate and to oxidize phenols and dyes to a variety of colorless
nontoxic products.
275
-------
Oxidation of cyanide to cyanate is illustrated below:
CN" + 03 —«- CNCT + 02
Continued exposure to ozone will convert the cyanate formed to
carbon dioxide and ammonia; however, this is not economically
practical.
Ozone oxidation of cyanide to cyanate requires 1.8 to 2.0 pounds
ozone per pound of CN~; complete oxidation requires 4,6 to 5.0
pounds ozone per pound of CN~. Zinc, copper, and nickel cya-
nides are easily destroyed to a nondetectable level, but cobalt
and iron cyanides are more resistant to ozone treatment.
Advantages and Limitations. Some advantages of ozone oxidation
for handling process effluents are its suitability to automatic
control and on-site generation and the fact that reaction prod-
ucts are not chlorinated organics and no dissolved solids are
added in the treatment step. Ozone in the presence of activated
carbon, ultraviolet, and other promoters shows promise of reduc-
ing reaction time and improving ozone utilization, but the
process at present is limited by high capital expense, possible
chemical interference in the treatment of mixed wastes, and an
energy requirement of 25 kwh/kg of ozone generated. Cyanide is
not economically oxidized with 03 beyond the cyanate form.
Operational Factors. Reliability: Ozone oxidation is highly
reliable with proper monitoring and control, and proper prelimi-
nary treatment to control interfering substances.
Maintainability: Maintenance consists of periodic removal of
sludge, and periodic renewal of filters and desiccators required
for the input of clean dry air; filter life is a function of
input concentrations of detrimental constituents.
Solid Waste Aspects: Preliminary treatment to eliminate sub-
stances which will interfere with the process may be necessary.
Dewatering of sludge generated in the ozone oxidation process or
in an in-line process may be desirable prior to disposal.
Cyanide Oxidation by Ozone with UV Radiation
One of the modifications of the ozonation process is the simulta-
neous application of ultraviolet light and ozone for the treat-
ment of wastewater, including treatment of halogenated organics.
The combined action of these two forms produces reactions by
photolysis, photosensitization, hydroxylation, oxygenation, and
oxidation. The process is unique because several reactions and
reaction species are active simultaneously.
276
-------
Ozonation is facilitated by ultraviolet absorption because both
the ozone and the reactant molecules are raised to a higher
energy state so that they react more rapidly. In addition, free
radicals for use in the reaction are readily hydrolyzed by the
water present. The energy and reaction intermediates created by
the introduction of both ultraviolet and ozone greatly reduce the
amount of ozone required compared with a system using ozone
alone. Figure VII-26 shows a three-stage UV-ozone system. A
system to treat mixed cyanides requires preliminary treatment
that involves chemical coagulation, sedimentation, clarification,
equalization, and pH adjustment.
Application and Performance. The ozone-UV radiation process was
developed primarily for cyanide treatment in the electroplating
and color photo-processing areas. It has been successfully
applied to mixed cyanides and organics from organic chemicals
manufacturing processes. The process is particularly useful for
treatment of complexed cyanides such as ferricyanide, copper
cyanide, and nickel cyanide, that are resistant to ozone.
Demonstration Status. Ozone combined with UV radiation is a
relatively new technology. Four units^are currently in operation
and all four treat cyanide-bearing waste although none are used
at copper forming plants.
Cyanide Oxidation by Hydrogen Peroxide
Hydrogen peroxide oxidation removes both cyanide and metals in
cyanide-containing wastewaters. In this process, cyanide-bearing
waters are heated to 49°C to 54°C (120°F to 130°F) and the pH is^
adjusted to 10.5 to 11.8. Formalin (37 percent formaldehyde) is
added while the tank is vigorously agitated.- After two to five
minutes, a proprietary peroxygen compound (41 percent hydrogen
peroxide with a catalyst and additives) is added. After an hour
of mixing, the reaction is complete. The cyanide is converted to
cyanate and the metals are precipitated as oxides or hydroxides.
The metals are then removed from solution by either settling or
filtration.
The main equipment required for this process is two holding tanks
equipped with heaters and air spargers or mechanical stirrers.
These tanks may be used in a batch or continuous fashion, with
one tank being used for treatment while the other is being
filled. A settling tank or a filter is needed to concentrate the
precipitate.
Application and Performance. The hydrogen peroxide oxidation
process is applicable to cyanide-bearing wastewaters, especially
those containing metal-cyanide complexes. In terms of waste
reduction performance, this process can reduce total cyanide to
277
-------
less than 0.1 mg/1 and the zinc or cadmium concentrations to less
than 1.0 mg/1.
!
Advantages and Limitations. Chemical costs are similar to those
for alkaline chlorination using chlorine and lower than those for
treatment with hypochlorite. All free cyanide reacts and is com-
pletely oxidized to the less toxic cyanate state. In addition,
the metals precipitate and settle quickly, and they may be recov-
erable in many instances; however, the process requires energy
expenditures to heat the wastewater prior to treatment.
Demonstration Status. This treatment process was introduced in
1971 and is used in several facilities. Np copper forming plants
use oxidation by hydrogen peroxide.
i
Evaporation
Evaporation is a concentration process. Water is evaporated from
a solution, increasing the concentration of solute in the remain-
ing solution. If the resulting water vapor is condensed back to
liquid water, the evaporation-condensation process is called dis-
tillation. However, to be consistent with industry terminology,
evaporation is used in this report to describe both processes.
Both atmospheric and vacuum evaporation are commonly used in
industry today. Specific evaporation techniques are shown in
Figure VII-27 and discussed below. •
I
Atmospheric evaporation could be accomplished simply by boiling
the liquid. To aid evaporation, heated liquid is sprayed on an
evaporation surface, and air is blown over the surface and subse-
quently released to the atmosphere. Thus, evaporation.occurs by
humidification of the air stream, similar to a drying process.
Equipment for carrying out atmospheric evaporation is quite
similar for most applications. The major element is generally a
Jacked column with an accumulator bottom. Accumulated wastewater
s pumped from the base of the column, through a, heat exchanger,
and back into the top of the column, where it is sprayed into the
packing. At the same time, air drawn upward through the packing
by a fan is heated as it contacts the hot liquid. The liquid
partially vaporizes and humidifies the air stream. The fan then
blows the hot, humid air to the outside atmosphere. A scrubber
is often unnecessary because the packed column itself acts as a
scrubber.
j
Another form of atmospheric evaporator also works on the air
humidification principle, but the evaporated water is recovered
for reuse by condensation. These air humidification techniques
operate well below the boiling point of water and can utilize
waste process heat to supply the energy required.
278
-------
In vacuum evaporation, the evaporation pressure is lowered to
cause the liquid to boil at reduced temperatures. All of^the
water vapor is condensed and, to maintain the vacuum condition,
noncondensible gases (air in particular) are removed by a vacuum
pump. Vacuum evaporation may be either single or double effect.
In double effect evaporation, two evaporators are used, and the
water vapor from the first evaporator (which may be heated by
steam) is used to supply heat to the second evaporator. As it
supplies heat, the water vapor from the first evaporator con-
denses. Approximately equal quantities of wastewater are evapo-
rated in each unit; thus, the double effect system evaporates
twice the amount of water that a single effect system does, at
nearly the 'same cost in energy but with added capital cost and
complexity. The double effect technique is thermodynamically
possible because the second evaporator is maintained at lower
pressure (higher vacuum) and, therefore, lower evaporation tem-
perature. Another means of increasing energy efficiency is vapor
recompression (thermal or mechanical), which enables heat to be
transferred from the condensing water vapor to the evaporating
wastewater. Vacuum evaporation equipment may be classified as
submerged tube or climbing film evaporation units.
In the most commonly used submerged tube evaporator, the heating
and condensing coil are contained in a single vessel to reduce
capital cost. The vacuum in the vessel is maintained by an
eductor-type pump, which creates the required vacuum by the flow
of the condenser cooling water through a venturi. Wastewater
accumulates in the bottom of the vessel, and it is evaporated by
means of submerged steam coils. The resulting water vapor con-
denses as it contacts the condensing coils in the top of^the
vessel. The condensate then drips off the condensing coils into
a collection trough that carries it out of the vessel. Con-
centrate is removed from the bottom of the vessel.
The major elements of the climbing film evaporator are the evapo-
rator, separator, condenser, and vacuum pump. Wastewater is
"drawn" into the system by the vacuum so that a constant liquid
level is maintained in the separator. Liquid enters the steam-
jacketed evaporator tubes, and part, of it evaporates so that a
mixture of vapor and liquid enters the separator. The design of
the separator is such that the liquid is continuously circulated
from the separator to the evaporator. The vapor entering the
separator flows out through a mesh entrainment separator to the
condenser, where it is condensed as it flows down through the
condenser tubes. The condensate, along with any entrained air,
is pumped out of the bottom of the condenser by a liquid ring
vacuum pump. The liquid seal provided by the condensate keeps
the vacuum in the system from being broken.
279
-------
Application and Performance. Both atmospheric and vacuum
evaporation are used in many, industrial plants, mainly for the
concentration and recovery of process solutions. Many of these
evaporators also recover water for rinsing. Evaporation has also
been applied to recovery of phosphate metal-cleaning solutions.
In th'eory, evaporation should yield a concentrate and a deionized
condensate. Actually, carry-over has resulted in coridensate
metal concentrations as high as 10 mg/1, although the usual level
is less than 3 iag/1, pure enough for most final rinses. The con-
densate may also contain organic brighteners and antifoaming
agents. These can be removed with an activated carbon bed, if
necessary. Samples from one plant showed 1,900 mg/1 zinc in the
feed, 4,570 mg/1 in the concentrate, and 0.4 mg/1 in the condens-
ate. Another plant had 416 mg/1 copper in the feed and 21,800
mg/1 in the concentrate. Chromium analysis for that plant indi-
cated 5,060 mg/1 in the feed and 27,500 mg/1 in the concentrate.
Evaporators are available in a range of capacities, typically
from 15 to 75 gph, and may be used in parallel arrangements for
processing of higher flow rates.
Advantages and Limitations. Advantages of the evaporation pro-
cess ^ are that it permits recovery of a wide variety of process
chemicals, and it is often applicable to concentration or removal
of compounds which cannot be accomplished by any other means.
The major disadvantage is that the evaporation process consumes
relatively large amounts of energy for the evaporation of water.
The recovery of waste heat from many industrial processes (e.g.,
diesel generators, incinerators, boilers, and furnaces) should be
considered as a source of this heat for a totally integrated
evaporation system. Also, in some cases solar heating could be
inexpensively and effectively applied to evaporation units. For
some applications, preliminary treatment may be required to
remove solids or bacteria which tend to cause fouling in the
condenser or evaporator. The buildup of scale on the evaporator
surfaces reduces the heat transfer efficiency and may present a
maintenance problem or increase operating 'cost. It has been
demonstrated that fouling of the heat transfer surfaces can be
avoided or minimized for1 certain dissolved solids by maintaining
a seed slurry which provides preferential sites for precipitate
deposition. In addition, low temperature differences in the
evaporator will eliminate nucleate boiling and supersaturation
effects. Steam distillable impurities in the process stream are
carried over with the product water and must be handled by
preliminary or post treatment. '.
\
Operational Factors. Reliability: Proper maintenance will
ensure a high degree of reliability for the system. Without such
attention, rapid fouling or deterioration of vacuum seals may
occur, especially when handling corrosive liquids.
280
-------
Maintainability: Operating parameters can be automatically
controlled. Preliminary treatment may be required, as well as
periodic cleaning of the system. Regular replacement of seals,
especially in a corrosive environment, may be necessary.
Solid Waste Aspects: With only a few exceptions, the process
does not generate appreciable quantities of solid waste.
Demonstration Status. Evaporation is a fully developed, com-
mercially available wastewater treatment system. It is used
extensively to recover plating chemicals in the electroplating
industry and a pilot scale unit has been used in connection with
phosphating of aluminum. Proven performance in silver recovery
indicates that evaporation could be a useful treatment operation
for the photographic industry, as well as for metal finishing.
Gravity Sludge ^Thickening
In the gravity thickening process, dilute sludge is fed from a
primary settling tank or clarifier to a thickening tank where
rakes stir the sludge gently to densify it and to push it to a
central collection well. The supernatant is returned to the
primary settling tank. The thickened sludge that collects on the
bottom of the tank is pumped to dewatering equipment or hauled
away. Figure VII™28 shows the construction of a gravity
thickener.
Application and Performance. Thickeners are generally used in
facilities where the sludge is to be further dewatered by a com-
pact mechanical device such as a vacuum filter or centrifuge.
Doubling the solids content in the thickener substantially
reduces capital and operating cost of the subsequent dewatering
device and also reduces cost for hauling. The process is
potentially applicable to almost any industrial plant.
Organic sludges from sedimentation units of 1 to 2 percent solids
concentration can usually be gravity thickened to 6 to 10 per-
cent; chemical sludges can be thickened to 4 to 6 percent.
Advantages and Limitations. The principal advantage of a gravity
sludge thickening process is that it: facilitates further sludge
dewatering. Other advantages are high reliability and minimum
maintenance requirements.
Limitations of the sludge thickening process are its sensitivity
to the flow rate through the thickener and the^sludge removal
rate. These rates must be low enough not to disturb the
thickened sludge.
281
-------
Operational Factors. Reliability: Reliability is high with
proper design and operation. A gravity thickener is designed on
the basis of square feet per pound of solids per day, in which
the required surface area is related to the solids entering and
leaving the unit. Thickener area requirements are also expressed
in terms of mass loading, kilograms of solids per sqxiare meter
per day (Ibs/sq ft/day).
Maintainability: Twice a year, a thickener must be shut down for
lubrication of the drive mechanisms. Occasionally, water must be
pumped back through the system in order to clear sludge pipes.
Solid Waste Aspects: Thickened sludge from a gravity thickening
process will usually require further dewatering prior to dispo-
sal, incineration, or drying. The clear effluent may be recircu-
lated in part, or it may be subjected to further treatment prior
to discharge.
Demonstration Status. Gravity sludge thickeners are used
throughout industry to reduce sludge water content to a level
where the sludge may be efficiently handled. Further dewatering
is usually practiced to minimize costs of hauling the sludge to
approved landfill areas.
Ion Exchange ,
Ion exchange is a process in which ions, held by electrostatic
forces to charged functional groups on the surface of the ion
exchange resin, are exchanged for ions of similar charge from the
solution in which the resin is immersed. This is classified as a
sorption process because the exchange occurs on the surface of
the resin, and the exchanging ion must undergo a phase transfer
from solution phase to solid phase. Thus,, ionic contaminants in
a waste stream can be exchanged for the harmless ions of the
resin.
j
Although the precise technique may vary slightly according to the
applzcation involved, a generalized process description follows.
The wastewater stream being treated passes through a filter to
remove any solids, then flows through a cation exchanger which
contains the ion exchange resin. Here, metallic impurities such
as copper, iron, and trivalent chromium are retained. The stream
then passes through the anion exchanger and its assocaited resin.
Hexavalent chromium (in the form of chromate or dichromate), for
example, is retained in this stage. If one pass does not reduce
the contaminant levels sufficiencly, the stream may then enter
another series of exchangers. Many ion exchange systems are
equipped with more than one set of exchangers for this reason.
282
-------
The other major portion of the ion exchange process concerns the
regeneration of the resin, which now holds those impurities
retained from the waste stream. An ion exchange unit with
lii-place-regeneration is shown in Figure VII-29. Metal ions such
as nickel are removed by an acid, cation exchange resin, which is
regenerated with hydrochloric or sulfuric acid, replacing the
metal ion with one or more hydrogen ions. Anions such as dichro-
mate are removed by a basic anion exchange resin, which is regen-
erated with sodium hydroxide, replacing the anion with one or
more hydroxyl ions. The three principal methods employed by
industry for regenerating the spent resin are:
(A) Replacement Servicer-.. A regeneration service replaces
the spent resin with regenerated resin, and regenerates
the spent resin at its own facility. The service then
has the problem of treating and disposing of the spent
regenerant.
(B) In-Place Regeneration: Some establishments may find it
less expensive to do their own regeneration. The spent
resin column is shut down for perhaps an hour, and the
spent resin is regenerated. * This results in one or
more waste streams which must be treated in an appro-
priate manner. Regeneration is performed as the resins
require it, usually every few months.
(C) Cyclic Regeneration: In this process, the regeneration
of the spent resins takes place within the ion exchange
unit itself in alternating cycles with the ion removal
process. A regeneration frequency of twice an hour^is
typical. This very short cycle time permits operation
with a very small quantity of resin and with fairly
concentrated solutions, resulting in a very compact
system. Again, this process varies according to^appli-
cation, but the regeneration cycle generally begins
with caustic being pumped through the anion exchanger,
carrying out hexavalent chromium, for example, as
sodium dichromate. The sodium dichromate stream then
passes through a cation exchanger, converting the
sodium dichromate to chromic acid. After concentration
by evaporation or other means, the chromic acid can be
returned to the process line. Meanwhile, the cation
exchanger is regenerated with sulfuric acid, resulting
in a waste acid stream containing the metallic impuri-
ties removed earlier. Flushing the exchangers with
water completes the cycle. Thus, the wastewater is
purified and, in this example, chromic acid is recov-
ered. The ion exchangers, with newly regenerated
resin, then enter the ion removal cycle again.
283
-------
Application and Performance. The list of pollutants for which
the ion exchange system has proven effective includes aluminum,
arsenic, cadmium, chromium (hexavalent and trivalent), copper,
cyanide, gold, iron, lead, manganese, nickel, selenium, silver,
tin, zinc, and others. Thus, it can be applied to a wide variety
of industrial concerns. Because of the heavy concentrations of
metals in their wastewater, the metal finishing industries util-
ize ion exchange in several ways. As an end-of-pipe treatment,
ion exchange is certainly feasible, but its greatest value is in
recovery applications. It is commonly used as an integrated
treatment to recover rinse water and process chemicals. Some
electroplating facilities use ion exchange to concentrate and
purify plating baths. Also, many industrial concerns, including
a number of aluminum forming plants, use ion exchange to reduce
salt concentrations in incoming water sources.
i
Ion exchange is highly efficient at recovering metal-bearing
solutions. Recovery of chromium, nickel, phosphate solution, and
sulfuric acid from anodizing is common. A chromic acid recovery
efficiency of 99.5 percent has been demonstrated. Typical data
for purification of rinse water are displayed in Table VII-25.
•
Advantages and Limitations. Ion exchange is a versatile technol-
ogy applicable to a great many situations. This flexibility,
along with its compact nature and performance, makes ion exchange
a very effective method of wastewater treatment. However, the
resins in these systems can prove to be a ^limiting factor. The
thermal limits of the ariion resins, generally in the vicinity of
60 C, could prevent its use in certain situations. Similarly,
nitric acid, chromic acid, and hydrogen peroxide can all damage
the resins, as will iron, manganese, and copper when present with
sufficient concentrations of dissolved oxygen. Removal of a par-
ticular trace contaminant may be uneconomical because of the
presence of other ionic species that are preferentially removed.
The regeneration of the resins presents its own problems. The
cost of the regenerative chemicals can be high. In addition, the
waste streams originating from the regeneration process are
extremely high in pollutant concentrations, although low in
volume. These must be further processed for proper disposal.
Operational Factors. Reliability: With the exception of occa-
sional clogging or fouling of the resins, ion exchange has proved
to be a highly dependable technology. '
Maintainability: Only the normal maintenance of pumps, valves,
piping, and other hardware used in the regeneration process is
required.
I
Solid Waste Aspects: Few, if any, solids accumulate within the
ion exchangers, and those which do appear are removed by the
284
-------
regeneration process. Proper prior treatment and planning can
eliminate solid buildup problems altogether. The brine resulting
from regeneration of the ion exchange resin most usually must be
treated to remove metals before discharge. This can generate
solid waste.
Demonstration Status. All of the ion exchange applications
discussed in this section are in commercial use, and industry
sources estimate the number of ion exchange units currently in
the field at well over 120. The research and development in ion
exchange is focusing on improving the quality and efficiency of
the resins, rather than new applications. Work is also being
done on a continuous regeneration process whereby the resins are
contained on a fluid- transfusible belt. The belt passes through
a compartmented tank with ion exchange, washing, and regeneration
sections. The resins are therefore continually used and
regenerated. No such system, however, has been reported beyond
the pilot stage.
Insoluble Starch Xanthate
Insoluble starch xanthate is essentially an ion exchange medium
used to remove dissolved heavy metals from wastewater. The water
may then either be reused (recovery application) or discharged
(end-of-pipe application). In a commercial electroplating
operation, starch xanthate is coated on a filter medium. Rinse
water containing dragged out heavy metals is circulated through
the filters and then reused for rinsing. The starch-heavy metal
complex is disposed of and replaced periodically. Laboratory
tests indicate'that recovery of metals from the complex is
feasible, with regeneration of the starch xanthate. Besides
electroplating, starch xanthate is potentially applicable to
aluminum forming, coil coating, porcelain enameling, copper
fabrication, and any other industrial plants where dilute^metal
wastewater streams are generated. Its present use is limited to
one electroplating plant.
Peat Adsorption
Peat moss is a complex natural organic material containing lignin
and cellulose as major constituents.' These constituents, partic-
ularly lignin, bear polar functional groups, such as alcohols,
aldehydes, ketones, acids, phenolic hydroxides, and ethers, that
can be involved in chemical bonding. Because of the polar nature
of the material, its adsorption of dissolved solids^such_as
transition metals and polar organic molecules is quite high.
These properties have led to the use of peat as an agent for the
purification of industrial wastewater.
285
-------
Peat adsorption is a "polishing" process which can achieve very
low effluent concentrations for several pollutants. If the con-
centrations of pollutants are above 10 mg/1, then peat: adsorption
must be preceded by pH adjustment for metals precipitation and
subsequent clarification. Pretreatment is also required for
chromium wastes using ferric chloride and sodium sulfide. The
wastewater is then pumped into a large metal chamber called a
kier which contains a layer of peat through which the waste
stream passes. The water flows to a second kier for further
adsorption. The wastewater is then ready for discharge. This
system may be automated or manually operated.
I
Application and Performance. Peat adsorption can be used in
copper forming plants for removal of residual dissolved metals
from clarifier effluent. Peat moss may be used to treiat waste-
waters containing heavy metals such as mercury, cadmium, zinc,
copper, iron, nickel, chromium, and lead, as well as organic
matter such as oil, detergents, and dyes. Peat adsorption is
currently used commercially at a textile plant, a newsprint
facility, and a metal reclamation operation.
Table VII-26 contains performance figures obtained from pilot
plant studies. Peat adsorption was preceded by pH adjustment for
precipitation and by clarification.
In addition, pilot plant studies have shown that chelated metal
wastes, as well as the chelating agents themselves, are removed
by contact with peat moss.
Advantages and Limitations. The major advantages of the system
include its ability to yield low pollutant concentrations, its
broad scope in terms of the pollutants eliminated, and its capac-
ity to accept wide variations of wastewater composition.
Limitations include the cost of purchasing,! storing, and dispos-
ing of the peat moss; the necessity for regular replacement of
the peat may lead to high operation and maintenance costs. Also,
the pH adjustment must be altered according to the composition of
the waste stream.
I
Operational Factors. Reliability: The question of long-term
reliability is not yet fully answered. Although the manufacturer
reports it to be a highly reliable system, operating experience
is needed to verify the claim.
Maintainability: The peat moss used in this process soon
exhausts its capacity to adsorb pollutants. At that time, the
kiers must be opened, the peat removed, and; fresh peat placed
inside. Although this procedure is easily and quickly accom-
plished, it must be done at regular intervals, or the system's
efficiency drops drastically.
286
-------
Solid Waste Aspects: After removal from the kter, the spent peat
must be eliminated. If incineration is used, precautions should
be taken to ensure that those pollutants removed from the water
are not released again in the combustion process. Presence of
sulfides in the spent peat, for example, will give rise to sulfur
dioxide in the fumes from burning. The presence of significant
quantities of toxic heavy metals in copper forming wastewater
will in general preclude incineration of peat used in treating
these wastes.
Demonstration Status. Only three facilities currently use
commercial adsorption systems in the United States - a textile
manufacturer, a newsprint facility, and a metal reclamation firm.
No data have been reported showing the use of peat adsorption in
copper forming plants.
Membrane Filtration
Membrane filtration is a treatment system for removing precipi-
tated metals from a wastewater stream. It must therefore be
preceded by those treatment techniques which will properly pre-
pare the wastewater for solids removal. Typically, a membrane
filtration unit is preceded by pH adjustment or sulfide addition
for precipitation of the metals. These steps are followed by the
addition of a proprietary chemical reagent which causes the pre-
cipitate to be non-gelatinous, easily dewatered, and highly
stable. The resulting mixture of pretreated wastewater and
reagent is continuously recirculated through a filter module and
back into a recirculation tank. The filter module contains tubu-
lar membranes. While the reagent-metal hydroxide precipitate
mixture flows through the inside of the tubes, the water and any
dissolved salts permeate the membrane. When the recirculating_
slurry reaches a concentration of 10 to 15 percent solids, it is
pumped out of the system as sludge.
Application and Performance. Membrane filtration appears to be
applicable to any wastewater or process water containing metal
ions which can be precipitated using hydroxide, sulfide, or car-
bonate precipitation. It could function as the primary treatment
system, but also might find application as a polishing treatment
(after precipitation and settling) to ensure continued compliance
with metals limitations. Membrane filtration systems are being
used in a number of industrial applications, particularly in the
metal finishing area. They have also been used for heavy metals
removal in the metal fabrication industry and the paper industry.
The permeate is claimed by one manufacturer to contain less,than
the effluent concentrations shown in Table VII-27, regardless of
the influent concentrations. These claims have been largely sub-
stantiated by the analysis of water samples at various plants in
various industries.
287
-------
In the performance predictions for this technology, pollutant
concentrations are reduced to the levels shown in Table VII-27
unless lower levels are present in the influent stream.
i
Advantages and Limitations. A major advantage of the membrane
filtration system is that installations can use most of the
conventional end-of-pipe systems that may already be in place.
Removal efficiencies are claimed to be excellent, even with sud-
den variation of pollutant input rates; however, the effective-
ness of the membrane filtration system can be limited by clogging
of the filters. Because pH changes in the waste stream greatly
intensify clogging problems, the pH must be carefully monitored
and controlled. Clogging can force the shutdown of the system
and^may interfere with production. In addition, relatively high
capital cost of this system may limit its iuse.
Operational Factors. Reliability: Membrane filtration has been
shown to be a very reliable system, provided that the pH is
strictly controlled. Improper pH can result in the clogging of
the membrane. Also, surges in the flow rate of the waste stream
must be controlled in order to prevent solids from passing
through the filter and into the effluent.
Maintainability: The membrane filters must be regularly moni-
tored, and cleaned or replaced as necessary. Depending on the
composition of the waste stream and its flow rate, frequent
cleaning of the filters may be required. Flushing with hydro-
chloric acid for six to 24 hours will usually suffice. In
addition, the routine maintenance of pumps, valves, and other
plumbing is required.
Solid Waste Aspects: When the recirculating reagent-precipitate
slurry reaches 10 to 15 percent solids, it is pumped out of the
system. It can then be disposed of directly to a landfill or it
can undergo a dewatering process. Because this sludge contains
toxic metals, it requires proper disposal.
j
Demonstration Status. There are more than 25 membrane.filtration
systems presently in use on metal finishing and similar waste-
waters. Bench scale and pilot studies are being run in an
attempt to expand the list of pollutants for which this system is
known to.be effective. Although there are no data on the use of
membrane filtration in copper forming plants, the concept has
been successfully demonstrated using coil coating plant waste-
water.
288
-------
Reverse Osmosis
The process of osmosis involves the passage of a liquid through a
semipermeable membrane from a dilute to a more concentrated solu-
tion. Reverse osmosis (RO) is an operation in which pressure is
applied to the more concentrated solution, forcing the permeate
to diffuse through the membrane and into the more dilute solu-
tion. This filtering action produces a concentrate and a perme-
ate on opposite sides of the membrane. The concentrate can then
be further treated or returned to the original production opera-
tion for continued use, while the permeate water can be recycled
for use as clean water. Figure VII-30 depicts.a reverse osmosis
system.
As illustrated in Figure VII-31, there are three basic configura-
tions used in commercially available RO modules: tubular,
spiral-wound, and hollow fiber. All of these operate on the
principle described above, the major difference being their
mechanical and structural design characteristics.
The tubular membrane module uses a porous tube with a cellulose
acetate membrane-lining. A common tubular module consists of a
length of 2.5 cm (1 inch) diameter tube wound on a supporting
spool and encased in a plastic shroud. Feed water is driven into
the tube under pressures varying from 40 to 55 atm (600 to 800
psi). The permeate passes through the walls of the tube and is
collected in a manifold while the concentrate is drained off at
the end of the tube. A less widely used tubular RO module uses a
straight tube contained in a housing, under the same operating
conditions.
Spiral-wound membranes consist of a porous backing sandwiched
between two cellulose acetate membrane sheets and bonded along
three edges. The fourth edge of the composite sheet is attached
to a large permeate collector tube. A spacer screen is then
placed on top of the membrane sandwich and the entire stack is
rolled around the centrally located tubular permeate collector.
The rolled up package is inserted into a pipe able to withstand
the high operating pressures employed in this process, up to 55
atm (800 psi) with the spiral-wound module. When the system is
operating, the pressurized product water permeates the membrane
and flows through the backing material to the central collector
tube. The concentrate is drained off at the end of the container
pipe and can be reprocessed or sent to further treatment facili-
ties.
The hollow fiber membrane configuration is made up of a bundle of
polyamide fibers of approximately 0.0075 cm (0.003 in.) OD and
0.043 cm (0.0017 in.) ID. A commonly used hollow fiber module
contains several hundred thousand of the fibers placed in a long
289
-------
tube, wrapped around a flow screen, and rolled into a spiral.
The fibers are bent in a U-shape and their ends are supported by
an epoxy bond. The hollow fiber unit is operated under 27 atm
(400 psi), the feed water being dispersed from the center of the
module through a porous distributor tube. Permeate flows through
the membrane to the hollow interiors of the fibers and is col-
lected at the ends of the fibers. .
The hollow fiber and spiral-wound modules have a distinct advan-
tage over the tubular system in that they are able to load a very
large membrane surface area into a relatively small volume. How-
ever, these two membrane types are much more susceptible to foul-
ing than the tubular system, which has a larger flow channel.
This characteristic also makes the tubulajr membrane much easier
to clean and regenerate than either the spiral-wound or hollow
fiber modules. One manufacturer claims that their helical
tubular module can be physically wiped clean by passing a soft
porous polyurethane plug under pressure through the module.
Application and Performance. In a number of metal processing
plants, the overflow from the first rinse in a countercurrent
setup is directed to a reverse osmosis unit, where it is sepa-
rated into two streams. The concentrated stream contains dragged
out chemicals and is returned to th6 bath to replace the loss of
solution due to evaporation and dragout. ! The dilute stream (the
permeate) is routed to the last rinse tank to provide water for
the rinsing operation. The rinse flows from the last tank to the
first tank and the cycle is complete.
The closed-loop system described above may be supplemented by the
addition of a vacuum evaporator after the RO unit in order to
further reduce the volume of reverse osmosis concentrate. The
evaporated vapor can be condensed and returned to the last rinse
tank or sent on for further treatment. ;
The largest application has been for the recovery of nickel solu-
tions. It has been shown that RO can generally be applied to
most acid metal baths with a high degree of performance, provid-
ing that the membrane unit is not overtaxed. The limitations
most critical here are the allowable pH range and maximum operat-
ing pressure for each particular configuration.
j
Adequate prefiltration is also essential.; Only three membrane
types are readily available in commercial RO units, and their
overwhelming use has been for the recovery of various acid metal
baths. For the purpose of calculating pei-formance predictions of
this technology, a rejection ratio of 98 percent is assumed for
dissolved salts, with 95 percent permeate recovery.
290
-------
Advantages and Limitations. The major advantage of reverse osmo-
sis tor handling process effluents Is its ability to concentrate
dilute solutions for recovery of salts and chemicals with low ^
power requirements. No latent heat of vaporization or fusion is
required for effecting separations; the main energy requirement
is for a high pressure p\imp. It requires relatively little , floor
space for compact, high capacity units, and it exhibits good
recovery and rejection rates for a number of typical process
solutions. A limitation of the reverse osmosis process for
treatment of process effluents is its limited temperature range
for satisfactory operation. For cellulose acetate systems, the
preferred limits are 18°C to 30°C (65°F to 85°F); higher tempera-
tures will increase the rate of membrane hydrolysis and reduce
system life, while lower temperatures will result^in decreased
fluxes with no damage to the membrane. Another limitation is
inability to handle certain solutions. Strong oxidizing agents,
strongly acidic or basic solutions, solvents, and other organic
compounds can cause dissolution of the membrane. Poor rejection
of some compounds such as borates and low molecular weight organ-
ics is another problem. Fouling of membranes by slightly soluble
components in solution or colloids has caused failures, and foul-
ing of membranes by feed waters with high levels of suspended
solids can be a problem. A. final limitation is inability to
treat or achieve high concentration with some solutions. Some
concentrated solutions may have initial osmotic pressures which
are so high that they either exceed available operating pressures
or are uneconomical to treat.
Operational Factors. Reliability: Very good reliability is _
achieved so long as the proper precautions are taken to minimize ,
the chances of fouling or degrading the membrane. Sufficient
testing of the waste stream prior to application of an RO system
will provide the information needed to insure a successful
application.
Maintainability: Membrane life is estimated to range from six
months to three years, depending on the use of the system. Down
time for flushing or cleaning is on the order of two hours as
often as once each week; a substantial portion of maintenance
time must be spent on cleaning any prefilters installed ahead of
the reverse osmosis unit.
Solid Waste Aspects: In a closed loop system utilizing RO there
is a constant recycle of permeate and a minimal amount of solid
waste. Prefiltration eliminates many solids before they reacn
the module and helps keep the buildup to a minimum. These solids
require proper disposal.
291
-------
Demonstration Status. There are presently at least one hundred
reverse osmosis wastewater applications in a variety of indus-
tries. In addition to these, there are 30 to 40 units being used
to provide pure process water for several industries. Despite
the many types and configurations of membranes, only the spiral-
wound cellulose acetate membrane has had widespread success in
commercial applications. One copper forming plant currently uses
reverse osmosis.
Sludge Bed Drying
..... -'— ^ ........... ..i ^ , ,.« |
As a waste treatment procedure, sludge bed drying is employed to
reduce the water content of a variety of sludges to the point
where they are amenable to mechanical collection and removal to a
landfill. These beds usually consist of 15 to 45 cm (6 to 18
in.) of sand over a 30 cm (12 in.) deep gravel drain system made
up of 3 to 6 mm (1/8 to 1/4 in.) graded gravel overlying drain
tiles. Figure VII-32 shows the construction of a drying bed.
I
Drying beds are usually divided into sectional areas approxi-
mately 7.5 meters ^ (25 ft) wide x 30 to 60 meters (100 to 200 ft)
long. The partitions may be earth embankments, but more often
are made of planks and supporting grooved posts.
To apply liquid sludge to the sand bed, a closed conduit or a
pressure pipeline with valved outlets at each sand bed section is
often employed. Another method of application is by means of an
open channel with appropriately placed side openings which are
controlled by slide gates. With either type of delivery system
a concrete splash slab should be provided to receive the falling
sludge and prevent erosion of the sand surface.
i
Where it is necessary to dewater sludge continuously throughout
the year regardless of the weather, sludge beds may be covered
with a fiberglass reinforced plastic or other roof. Covered
drying beds permit a greater volume of sludge drying per year in
most climates because of the protection afforded from rain or
snow and because of more efficient control of temperature.
Depending on the climate, a combination of open and enclosed beds
will prova.de maximum utilization of the sludge bed drying facili-
Application and Performance. Sludge drying beds are a means of
dewatering sludge from clarifiers and thickeners. They are
widely used both in municipal and industrial treatment facili-
ties.
Dewatering of sludge on sand beds occurs by two mechanisms: fil
tration of water through the bed and evaporation of water as a
result ^of radiation and convection. Filtration is generally com
plete in one to two days and may result in solids concentrations
292
-------
as high as 15 to 20 percent. The rate of filtration depends on
the drainability of the sludge.
The rate of air drying of sludge is related to temperature, rela-
tive humidity, and air velocity. Evaporation will proceed at a
constant rate to a critical moisture content, then at a falling
rate to an equilibrium moisture content. The average evaporation
rate for a sludge is about 75 percent of that from a free water
surface.
Advantages and Limitations. The main advantage of sludge drying
beds over other types of sludge dewatering is the relatively low
cost of construction, operation, and maintenance.
Its disadvantages are the large area of land required and long
drying times that depend, to a great extent on climate and
weather.
Operational Factors. Reliability: Reliability is high with
favorable climatic conditions, proper bed design, and^care to
avoid excessive or unequal sludge application. If climatic con-
ditions in a given area are not favorable for adequate drying, a
cover may be necessary.
Maintainability: Maintenance consists basically of periodic
removal of the dried sludge. Sand removed from the drying bed
with the sludge must be replaced and the sand layer resurfaced.
The resurfacing of sludge beds is the major expense item in
sludge bed maintenance, but there are other areas which may
require attention. Underdrains occasionally become clogged and
have to be cleaned. Valves or sludge gates that control the flow
of sludge to the beds must be kept watertight. Provision for
drainage of lines in winter should be provided to prevent damage
from freezing. The partitions between beds should be tight.so
that sludge will not flow from one compartment to another.^ The
outer walls or banks around the beds should also be watertight.
Solid Waste Aspects: The full sludge drying bed must either^be
abandoned or the collected solids must be removed to a landfill.
These solids contain whatever metals or other materials were
settled in the clarifier. Metals will be present as hydroxides,
oxides, sulfides, or other salts. They have the potential for
leaching and contaminating ground water, whatever the location of
the semidried solids. Thus the abandoned bed or landfill should
include provision for runoff control and leachate monitoring.
Demonstration Status. Sludge beds have been in common use in
both municipal and industrial facilities for many years. How-
ever, protection of ground water from contamination is not always
adequate.
293
-------
Ultrafiltration
i
Ultrafiltration (UF) is a process which uses semipermeable poly-
meric membranes to separate emulsified or colloidal materials
suspended in a liquid phase by pressurizing the liquid so that it
permeates the membrane. The membrane of an ultrafilter forms a
m?ifcular screen which retains molecular particles based on their
differences in size, shape, and chemical structure. The membrane
permits passage of solvents and lower molecular weight molecules.
At present, an ultrafilter is capable of removing materials with
molecular weights in the range of 1,000 to 100,000 and particles
of comparable or larger sizes.
In an Ultrafiltration process, the feed solution is pumped
through a tubular membrane unit. Water and some low molecular
weight materials pass through the membrane under the applied
pressure of 10 to 100 psig. Emulsified oil droplets and sus-
pended particles are retained, concentrated, and removed continu-
ously. In contrast to ordinary filtration, retained materials
are washed off the membrane filter rather than held by it.
Figures VII-33 and VII-34 represent the Ultrafiltration process.
]
Application and Performance. Ultrafiltration has potential
application to aluminum forming plants for separation of oils and
residual solids from a variety of waste streams. In treating
aluminum forming wastewater its greatest applicability would be
as a polishing treatment to remove residual precipitated metals
after chemical precipitation and clarification. Successful
commercial use, however, has been primarily for separation of
emulsified oils from wastewater. Over one hundred such units
operate in the United States, treating emulsified oils from
now
a
variety of industrial processes. Capacities of currently oper-
ating units range from a few hundred gallons a week to 50,000
gallons per day. Concentration of oily emulsions to 60 percent
oil or more are possible. Oil concentrates of 40 percent or more
are generally suitable for incineration, and the permeate can be
treated further and in some cases recycled back to the process.
In this way, it is possible to eliminate contractor removal costs
tor oil from some oily waste streams.
Table VII-28 indicates Ultrafiltration performance (note that UF
is not intended to remove dissolved solids). The removal
percentages shown are typical, but they can be influenced by pH
and other conditions. The high TSS level is unusual for this
technology and Ultrafiltration is assumed to reduce the TSS level
by one-third after mixed media filtration.[
294
-------
The permeate or effluent from the ultrafiltration unit is nor-
mally of a quality that can be reused in industrial applications
or discharged directly. The concentrate from the ultrafiltration
unit can be disposed of as any oily or solid waste.
Advantages and Limitations. Ultrafiltration is sometimes an
attractive alternative to chemical treatment because of lower
capital equipment, installation, and operating costs, very high
oil and suspended solids removal, and little required pretreat-
ment. It places a positive barrier between pollutants and
effluent which reduces the possibility of extensive pollutant ^
discharge due to operator error or upset in settling and skimming
systems. Alkaline values in alkaline cleaning solutions can be
recovered and reused in the process.
A limitation of ultrafiltration for treatmentQof process
effluents is its narrow temperature range (18 C to 30 C; for
satisfactory operation. Membrane life decreases with higher
temperatures, but flux increases at elevated temperatures.
Therefore, sxirface area requirements are a function of tempera-
ture and become a tradeoff between initial costs and replacement
costs for the membrane. In addition, ultrafiltration cannot
handle certain solutions. Strong oxidizing agents, solvents, and
other organic compounds can dissolve the membrane. Fouling is
sometimes a problem, although the high velocity of the wastewater
normally creates enough turbulence to keep fouling at a minimum.
Large solids particles can sometimes puncture the membrane and
must be removed by gravity settling or filtration prior to the
ultrafiltration unit.
Operational Factors. Reliability: The reliaiblity of an ultra-
filtration system is dependent on the proper filtration, set-
tling or other treatment of incoming waste streams to prevent_
damage to the membrane. Careful pilot studies should be done in
each instance to determine necessary pretreatment steps and the
exact membrane type to be used. It: is advisable to remove any
free, floating oil prior to ultrafiltration. Although free oil
can be processed, membrane performance may deteriorate.
Maintainability: A limited amount of regular maintenance is
required for the pumping system. In addition, membranes must be
periodically changed. Maintenance associated with membrane^
plugging can be reduced by selection of a membrane with optimum
physical characteristics and sufficient velocity of the waste
stream. It is often necesary to occasionally pass a detergent
solution through the system to remove an oil and grease film
which accumulates on the membrane. With proper maintenance,
membrane life can be greater than 12 months.
295
-------
Solid Waste Aspects: Ultrafiltration is used primarily to
recover solids and liquids. It therefore eliminates solid waste
problems when the solids (e.g., paint solids) can be recycled to
the process. Otherwise, the stream containing solids must be
treated by end-of-pipe equipment. In the most probable applica-
tions within the aluminum forming category, the ultrafilter would
remove concentrated oily wastes which can be recovered for reuse
or used as a fuel.
Demonstration Status. The ultrafiltration-process is well devel-
oped and commercially available for treatment of wasteiwater or
recovery of certain high molecular weight liquid and solid con-
taminants. Currently, no plants in the copper forming category
use ultrafiltration. One aluminum forming plant ultrafilters its
spent rolling oils. Ultrafiltration is well suited for highly
concentrated emulsions, for example, rolling and drawing oils,
although it is not suitable for free oil.
Vacuum Filtration
i
In wastewater treatment plants, sludge dewatering by vacuum fil-
tration generally uses cylindrical drum filters. These drums
have a filter medium which may be cloth made of natural or syn-
thetic fibers or a wire-mesh fabric. The drum is suspended above
and dips into a vat of sludge. As the drum rotates slowly, part
of its circumference is subject to an internal vacuum that draws
sludge to the filter medium. Water is drawn through the porous
filter cake thorugh the drum fabric to a discharge port, and the
dewatered sludge, loosened by compressed air, is scraped from the
filter mesh. Because the dewatering of sludge on vacuum filters
is relatively expensive per kilogram of water removed, the liquid
sludge is frequently thickened prior to processing. A vacuum
filter is shown in Figure VII-35.
Application and Performance. Vacuum filters are frequently used
both in municipal treatment plants and in a wide variety of
industries. They are most commonly used in larger facilities,
which may have a thickener to double the sqlids content of clari-
fier sludge before vacuum filtering. Often a precoat is used to
inhibit filter blinding.
The function of vacuum filtration is to reduce the water content
of sludge, so that the solids content increases from about 5
percent to between 20 and 30 percent, depending on the waste
characteristics.
Advantages and Limitations. Although the initial cost and area
requirement of the vacuum filtration system are higher than those
of a centrifuge, the operating cost is lower, and no special pro-
visions for sound and vibration protection ineed be made. The
296
-------
de-watered sludge from this process is in the form of a moist cake
and can be conveniently handled.
Operational Factors. Reliability: Vacuum filter systems ^
proven reliable at many industrial and municipal treatment facil-
ities. At present, the largest municipal installation is^at^the
West Southwest wastewater treatment plant of Chicago, Illinois,
where 96 large filters were installed in 1925, functioned approx-
imately 25 years, and then were replaced with larger units.
Original vacuum filters at Minneapolis-St. Paul, Minnesota now
have over 28 years of continuous service, and Chicago has some
units with similar or greater service life.
Maintainability: Maintenance consists of the cleaning or
replacement of the filter media, drainage grids, drainage piping,
filter pans, and other parts of the equipment. Experience in a
number of vacuum filter plants indicates that maintenance
consumes approximately 5 to 15 percent of the total time. If
carbonate buildup or other problems are unusually severe, mainte-
nance time may be as high as 20 percent. For this reason, it is
desirable to maintain one or more spare units.
If intermittent operation is used, the filter equipment should be
drained and washed each time it is taken out of service. An
allowance for this wash time must be made in filtering schedules.
Solid Waste Aspects: Vacuum filters generate a solid cake which
is usually trucked directly to landfill. All of the metals
extracted from the plant wastewater are concentrated in the
filter cake as hydroxides, oxides, sulfides, or other salts.
Demonstration Status. Vacuum filtration has been widely used for
many years. It is a fully proven, conventional technology for
sludge dewatering. Several copper forming plants report its use.
IN-PLANT CONTROL TECHNIQUES (FLOW REDUCTION)
This section presents a discussion of flow reduction techniques
which are applicable to copper forming plants for the purpose of
reducing the volume of wastewater discharged to treatment. Flow
reduction is a control technique which, in conjunction with the
treatment processes previously discussed, can further reduce the
mass of pollutants discharged. The primary flow reduction
techniques which are applicable to copper forming plants are
recycle, alternative rinsing techniques, particularly spray
rinsing and counter cur rent rinsing, contract hauling and
reduction of water use.
297
-------
Recycle j
Nearly all copper forming plants recycle some process wastewater
streams. The most commonly reeyelecL streams include spent lubri-
cating solutions, annealing contact cooling water and solution
heat treatment contact cooling water. In general, some treatment
is required to allow process wastewater recycle in this industry
but the required treatment is generally less than that needed for
discharge. At present, the most common treatment practices
prior to recycle in copper forming plants are suspended solids
removal, oil skimming, and cooling. Wastewater is most often
returned to the process operation from which it originated, but
may also be used in other operations.
Recycle is highly effective in reducing pollutant discharges,
often eliminating the discharge completely. Where a discharge
remains, the volume requiring treatment is greatly reduced,
making the application of advanced treatment techniques more
economically attractive. Recycle often results in considerably
reduced requirements for process materials and corresponding
reductions in raw waste loads for some pollutants (e.g., oil and
grease and toxic organics in soluble oil systems).
Where recycle is presently practiced, the rate of recycle varies
from approximately 30 to 100 percent. Many copper forming plants
currently achieve zero discharge of some waste streams through
natural evaporation or land application; however, these options
are not available to all plants in the industry. The Agency
recognizes that discharge of wastewater from particular sources
may not be avoided. This is discussed in greater detail in the
context of specific sources.
i
Cold Rolling, Hot Rolling and Drawing Lubricants. Lubricants
used in cold rolling and drawing are commonly recycled to such an
extent that contract removal of the total discharge is practical.
Factors which limit the extent of recycling include heat removal,
degradation of lubricants which results in staining of the
product, or build-up of dissolved or suspended solids. These
limitations may often be overcome by the application of more
advanced treatment techniques than those presently in common use
for recycle as discussed below.
The use of water soluble oil and emulsified oil lubricants in
cold rolling processes makes it easier to recycle lubricants than
in cases where non-emulsified oil--water mixtures are in use. In
addition, most drawing operations use emulsified lubricants.
Emulsified lubricants are commonly used repeatedly and dumped
when contamination forces replacement of the solution. This type
of technology uses much less process water and oil on a yearly
298
-------
basis than most processes which have continuous oil—water mix-
ture applications; therefore, both process material costs and
treatment or disposal costs can be reduced.
The most common problems encountered in the use of soluble oil
lubricants are the accumulations of heavy metals (especially
copper) and other suspended solids, and the degradation of the
emulsion due to heat and stress. Several methods are used to
prolong the life of the solutions, resulting in even lower ^
end-of-pipe treatment and/or disposal costs. Most recalculating
lubricant systems have a storage tank from which the lubricant is
drawn and to which it is returned following application to the
process material. This storage tank serves the dual purpose of
allowing solids to settle and the lubricant to cool prior to
recycle. Some of these tanks are baffled to enhance settling.
In some copper and copper alloy plants, paddle type devices
traveling on a conveyorized belt, scrape out, solids which
accumulate on the bottom of lubricant recirculation tanks. This
helps to minimize the contamination of the lubricant by avoiding
the build-up of solids on the bottom of the tank. The sludge
removed is often rich enough in copper fines to be sent out for
reclamation. Cartridge and membrane filtration is also known to
remove solids from lubricant streams. These filters^must be
cleaned or replaced as they become clogged with solids.
Annealing Contact Cooling Water. Annealing quenches using only
water are commonly recycled."Treatment of annealing quench
water prior to recycle is typically limited to settling and heat
removal; however, many sites reported recycle with no prior
treatment.
Because annealing quench operations are characteristically
intermittent, retention and equalization tanks are generally^
required for recycle. These tanks can also serve as a settling
basin for removal of suspended solids and sufficient cooling and
temperature equalization to allow a significant degree of recycle
without addition of non-contact cooling or the use of a cooling
tower.
Total recycle may be prohibited by the presence of dissolved
solids for plants which can not take advantage of natural evap-
oration or land application. Dissolved solids (e.g., sulfates
and chlorides) entering a totally recycled waste stream may
precipitate, forming scale if the solubility limits of the
dissolved solids are exceeded. A bleed stream may be necessary
to prevent maintenance problems (pipe plugging or scaling, etc.;
that would be created by the precipitation of dissolved solids.
Required hardware necessary for recycle is highly site-specific.
Recycling through cooling towers is the most common practice.
299
-------
Basic Items include the cooling tower, pumps and piping. Addi-
tional materials are necessary if water treatment occurs before
the water is recycled. Chemicals may be necessary to control
scale buildup, slime, and corrosion problems, especially with
recycled cooling water. Maintenance and energy use are limited
to that required by the pumps, and solid waste generation is
dependent on the type of treatment system in place. A typical
flow diagram for a system using a cooling tower to recycle water
is shown in Figure VII-36.
Solution Heat Treatment Contact Cooling Water. Water quenches
(solution heat treatment) are widely used in copper forming
plants following hot deformation processes to rapidly reduce
product temperatures in order to limit surface oxidation and
allow safe handling of the material. The quench water becomes
contaminated with metals, suspended solids, and lubricants, but
the primary effect of this use is elevation of the water tempera-
ture. Because only minor chemical changes! are produced in the
quench solutions, extensive recycle and reuse is possible without
deleterious effects on production.
In general, quench water associated with solution heat treatment
produces relatively large volumes of water which contain low
concentrations of pollutants. As a result treatment effective-
ness is somewhat limited unless in-process control techniques are
employed. Recycle and reuse of the quench water and a reduction
of water use can reduce the volume of effluent requiring treat-
ment and increase pollutant concentrations to more treatable
levels.
Alternative Rinsing Techniques
Reductic i in the amount of water used and (discharged in copper
and copper alloy manufacturing can be realized through the
installation and use of efficient rinsing techniques. The tech-
niques discussed are alternatives to stagnant rinsing. These
techniques can result in water cost savings, reduced waste treat-
ment chemical costs and improved waste treatment efficiency. The
design of rinse systems for minimum water use depends on the
maximum level of contamination allowed to remain on the work
piece (without reducing product quality) as well as on the
efficiency or effectiveness of each rinse stream.
i
Rinsing is used to dilute the concentration of contaminants
adhering to the surface of a workpiece to an acceptable level
before the workpiece passes on to the next,step of a pickling
operation. The amount of water required to dilute the rinse
solution depends on the quantity of chemical drag-in from the
upstream rinse or pickling tank, the allowable concentration of
chemicals in the rinse water, and the contacting efficiency
between the workpiece and the water.
300
-------
Counter-current Cascade Rinsing
Process variations such as countercurrent cascade rinsing may
cause a decrease in process water use. This technique reduces
water use by countercurrent multiple stage rinsing of the copper
products. Clean rinse water first contacts the copper in the
last stage. The water, somewhat more contaminated, is routed
stage by stage up the rinsing line. After use in the first rinse
stage, the contaminated water is discharged to treatment.
As an example, Figure VII-37 illustrates three rinsing opera-
tions, each designed to remove the residual acid in the water on
the surface of a workpiece. In Figure VII-37a the piece is
dipped into one tank with continuously flowing water. In this
case, the acid on the surface of the workpiece is essentially
diluted to the required level.
In Figure VII-37b, the first step towards countercurrent opera-
tion is taken with the addition of a second tank. The workpiece
is now moving in a direction opposite to the rinse water. The
piece is rinsed with fresh makeup water prior to moving down the
assembly line. However, the fresh water from this final rinse
tank is directed to a second tank, where it meets the incoming,
more-contaminated workpiece. Fresh makeup water is used to give
a final rinse to the article before it moves out of the rinsing
section, but the slightly contaminated water is reused to clean
the article just coming into the rinsing section. By increasing
the number of stages, as shown in Figure VII-37c, further water
reduction can be achieved. Theoretically, the amount of water
required is the amount of acid being removed by single-stage
requirements divided by the highest tolerable concentration in
the outgoing rinsewater. This theoretical reduction of water by
a countercurrent multistage operation is shown in the curve graph
in Figure VII-38. The actual flow reduction obtained is a
function of the dragout and the type of contact occurring in the
tanks. If reasonably good contact is maintained major reductions
in water use are possible.
Significant flow reductions can be achieved by the addition of
only one additional stage in the rinsing operation, as discussed
above. As shown in Figure VII-38 the largest reductions are made
by adding the first few stages. Additional rinsing stages cost
additional money. The actual number of stages added depends on
site-specific layout and operating conditions. With higher costs
for water and waste treatment, more stages might be economical.
With very low water costs, fewer stages would be economical. In
considering retrofit applications, the space available for
additional tanks is also important. Many other factors will
affect the economics of countercurrent cascade rinsing; an
evaluation must be done for each individual plant.
301
-------
Rinse water requirements and the benefits of countercurrent rins-
ing may be influenced by the volume of solution dragout carried
into each rinse stage by the material being rinsed, by the number
of rinse stages used, by the initial concentrations of impurities
being removed, and by the final product cleanliness required.
The influence of these factors is expressed in the rinsing
equation which may be stated simply as:
Vr
x VD
Vr is the flow through each rinse stage.
Co is the concentration of the contaminant(s) in the initial
process bath.
Cf is the concentration of the contaminant(s) in the final
rinse to give acceptable product cleanliness.
n is the number of rinse stages employed.
VD is the dragout carried into each rinse stage, expressed
as a flow.
For a multi-stage rinse, the total volume of rinse wastewater is
equal to n times Vr while for a countercurrent rinse the total
volume of wastewater discharge equals Vr. Drag-out is solution
which remains on the .surface of material being rinsed when it is
removed from process baths or rinses. i
i
In the copper forming category, countercurrent cascade rinsing
can be applied to pickling and alkaline cleaning rinsing
operations. To calculate the benefits of countercurrent rinsing
for copper forming, it can be assumed that a two-stage
countercurrent cascade rinse is installed after pickling. The
mass of copper in one square meter of sheet that is 6 mm
(0.006 m) in thickness can be calculated using the density of
copper, 8.90 kkg/m3 (556 Ibs/cu ft), as follows:
- (0.006 m) x (8.90 kkg/m3) = 0.053 kkg/m2 of sheet
Using the mean pickling rinse water use from Table V-12 (p. 97 ),
Vr can then be calculated as follows:
Vr - [0.053 kkg x 4,000
\ m^
\
- 213.6 1/m2 of sheet.
1 \
EEgj
302
-------
If the film on a piece of copper sheet is 0.015 mm (0.6 mil)
thick, (equivalent to the film on a well-drained vertical
surface) then the volume of process solution, VD, carried into
the rinse tank on one square meter of sheet will be:
VD = (0.015 mm) x / 1 m/mm\ x (1000 1/m3)
\TOUO~ /
= 0.015 1/m2 of sheet
Let r = Go, then r 1/n = Vr
CT VD
For single stage rinsing n = 1
Therefore r == Vr
W
and r = 213.7 = 14,240
U7TJT5
For a 2-stage countercurrent cascade rinse to obtain the same r,
that is the same product cleanliness,
Vr = r^/2 and:
W
119.3
But VD = 0.015 1/m2 of sheet
Vr
VD
Therefore for 2-stage countercurrent cascade rinsing Vr is:
Vr = 119.3 x 0.015 = 1.79 1/m2 of sheet.
In this example, two-stage countercurrent rinsing achieved 99.2
percent reduction in the water used. The actual numbers may vary
depending on efficiency of squeegees or air knives, and the rinse
ratio desired.
Countercurrent cascade rinsing has been widely used as a flow
reduction technique in the metal finishing industry. Counter-
current cascade rinsing is currently practiced at^four copper
forming plants. In aluminum conversion coating lines that are
subject to the coil coating limitations, countercurrent cascade
rinsing is currently used in order to reduce costs of wastewater
treatment systems (through smaller systems) for direct dis-
chargers and to reduce sewer costs for indirect dischargers.
303
-------
Spray Rinsing , ;
Spray rinsing is another method used to dilute the concentration
of contaminants adhering to the surface of a workpiece. The
basis of this approach is to spray water onto the surface of the
workplace, as opposed to submerging it into a tank. The amount of
water contacting the workpiece is minimized as is the amount of
water discharged. The water use and discharge rates can be
further reduced through recirculation of the rinse water. Copper
forming plants practicing spray rinsing discharge typically 60
percent less water than those plants using only stagnant rinses.
The equipment required for spray rinsing includes piping, spray
nozzles, a pump, a holding tank, and a collection basin. The
holding tank may serve as the collection basin to collect the
rinse water prior to recirculation as a method of space economi-
zation.
i
Contract Hauling
Contract hauling refers to the industry practice of contracting a
firm to collect and transport wastes for off-site disposal. This
practice is particularly applicable to low-Volume, high concen-
tration waste streams. Examples of such waste streams in the
copper forming industry are pickling baths, drawing lubricants,
cold rolling lubricants, annealing oil and extrusion press solu-
tion heat treatment. :
Reduction of Water Use
The reduction of process water use has been found to be an
effective approach to reducing treatment costs and pollutant dis-
charges at many copper forming plants. In most cases, substan-
tial reduction may be achieved by simple actions involving little
or no cost. It is often found that satisfactory operation may be
achieved with much smaller rinse or contact cooling water flows
than have generally been used. Many of the copper forming plants
visited reported recent significant reductions in process water
use and discharge.
Many production units in copper forming plants operate intermit-
tently or at widely varying production rateS. The practice of
shutting off process water streams during periods when the unit
is inoperative and of adjusting flow rates during periods of low
activity can prevent much unnecessary dilution of wastes and
reduce the volume of water to be treated and discharged. Water
may be shut off and adjusted manually or through automatically
controlled valves. Manual adjustment involves minimal capital
cost and can be just as reliable in actual practice. Automatic
304
-------
shut off valves are used in some copper forming^operations to
turn off water flows when production units are inactive. Auto-
matic adjustment of flow rates according to production
-------
are also used to reduce drag-out from soap and other lubricant
tanks which are often found as a final step in automatic strip
lines. v
i
i
Heating the tank containing the process bath can also help reduce
drag-out of process solutions in two ways: by decreasing the
viscosity and the surface tension of the solution. A lower
viscosity allows the liquid to flow more rapidly and therefore
drain at a faster rate from the product following application in
a process bath. Increasing 'the temperature of the solution
decreases its viscosity, thereby reducing the amount of process
solution which is dragged out into succeeding rinses. Likewise,
a higher temperature will result in lower surface tension in the
solution. The amount of work required to overcome the adhesive
force between a liquid film and a solid surface is a function of
the surface tension of the liquid and the contact angle. Lower-
ing the surface tension reduces the amount of work required to
remove the liquid and reduces the edge effect (the bead of liquid
adhering to the edges of a product).
Operator performance can have a substantial: effect on the amount
of drag-out which results from manual dip t|ank processes. Spe-
cifically, proper draining time and techniques can reduce the
amount of process solution dragged out into rinses. After dip-
ping the material into the process tank, drag-out can be reduced
significantly by simply suspending the product above the process
tank while solution drains off. Fifteen to 20 seconds generally
seems sufficient to accomplish this. When processing tubing,
especially, lowering one end of the load during this drain time
allows a larger amount of solution to run off from inside the
tubes.
All of the techniques which reduce water use discussed in this
section may be used at copper forming plants to achieve the
average production normalized flows at plants which presently
discharge excessive amounts of wastewater to treatment.
Current Industry Practice
Out of 18 plants which reported a discharge of annealing water,
six currently practice cooling and recycle. Reported recycle
rates range from 50 to 98 percent. Of 24 plants which reported
the use of water for solution heat treatment, eight plants also
reported the use of recycle with recycle rates from 85 to 100
percent.
A large number of plants which practice drawing, cold r-olling or
annealing with oil reported the practice of extensive recycling
of the lubricant streams with contract hauling of the small
306
-------
amounts of spent lubricant which is periodically discharged.
Eighteen out of 28 plants which have cold rolling operations
recycle and contract haul, thereby achieving zero discharge.
Similarily, 68 out of 80 plants which have drawing operations
achieve zero discharge through recycle and contract hauling. For
plants which practice annealing with oil, 23 out of 30 plants
achieve zero discharge of annealing oil through contract hauling.
The use of alternate rinsing techniques in pickling operations
was reported by approximately one-third of the 42 plants which
have pickling operations. The most frequently reported alternate
rinsing technique for pickling is spray rinsing. Spray rinsing
of pickling rinse water is practiced in 16 copper forming plants.
Countercurrent rinsing and multi-stage rinsing were also
reported. Countercurrent rinsing is currently practiced by four
plants in the copper forming industry.
307
-------
w
Q
H
X!
O
H
Q
Cd
CO
a
-------
1O
10
pH
Figure VII-2
COMPARATIVE SOLUBILITIES OF METAL HYDROXIDES
AND SULFIDE AS A FUNCTION OF pH
309
-------
J
O
.
O
o
•
o
0 0
o
o
0 C
coo
O
<
-------
0.40
0.30
Jt
o"
s
a 0.20
u
-i
0.10
\
CAUSTIC SODA
SODA ASH AND
CAUSTIC SODA
10.3
Figure VII-4
LEAD SOLUBILITY IN THREE ALKALIES
311
-------
INFLUENT
L_J_
(a)
30-40 in-* vlv'SANb-'-":
..'•.V/COARS'
EFFLUENT
(b)
6- 10 ft —
DEPTH
E
/-OVERFLOW
/ TROUGH
1 n n n n rTr
.FINE. :-.-.. ;..•;.;
•'.' .' '!•'•' '.' '•••*
."i •' '*•'•!.'•• ': •
•';';•;"; SANO •'.'•;:
/I .v COARSE'
f
t i EFFLUENT V fNFLU
UHOEHORAIN UNDERORAIN \
CHAMBER — * CHAMBER—*
INFLUENT
, , l~JL^J
(d)
COARSE MEDIA— —$
INTERMIX ZONE— p-
FINER MEDIA— —;:.'•;
FINEST MEDIA -s£
UNDERORAIN
CHAMBER — 1
(THRAc[fE; ~T
-%----.TT 30 -40 in
•VSA'N'OtVv-v:. 1
..*.••.•.*:•:•.'/-. I.
T EFFLUENT
X-SRIT TO
RETAIN / « N
SAND \ /
STRAINER -v
EFFLUENT
4-6ft >
i
ENT UNDEROR/
CHAM8E
1
1
(e)
COARSE MEDIA-—
INTERMIX ZONE-y--
FINER MEDIA— -*-
FINEST MEDIA —
t
i
UNDERDRAW
CHAMBER -
/.•..•nur.'.V'
""**•*' 4* '."• **"•.**' ; "
•'.''.COA'RSE.'-'-
• " - ' w . '
^~
MN \
B — i
INFLUENT
.ANTHRACITE
~;..;.:siLiCA-.-'r
^rrj^.rr.TTh.r^.-j:
1^
!
i
T
28- 48 in
!
\ 1 ^-GARNET S/
\ 'EFFLUENT
INFLUENT
Figure VII-5
\
FILTER CONFIGURATIONS
(a) Single-Media Conventional Filter.
(b) Single-Media Upflow Filter.
(c) Single-Media Biflow Filter.
(d) Dual-Media Filter.
(e) Mixed-Media (Triple-
Media) Filter.
312
-------
JNFUUENT
EFFLUEN
STORED
BACKWASH
WATER
0 COLLECTION CHAMBER
DRAIN
Figure VII-6
GRANULAR BED FILTRATION
313
-------
SEDIMENTATION BASIN
INLET ZONE
BAFFLES TO MAINTAIN
QUIESCENT CONDITIONS
OUTLET ZONE
INLET LIQUID
\.
SETTLING
. TRAJECTORY .
«._« • •
A
.?
'
OUTLET LIQUID
BELT-TYPE SOLIDS COLLECTION
MECHANISM
SETTLED PARTICLES COLLECTED
AND PERIODICALLY REMOVED
CIRCULAR CLARIFIER
INLET LIQUID
.CIRCULAR BAFFLE
SETTLING ZONE.
J'-Tr^,-
INLET ZONE -
• • V* • •
-.. . ' V v. %
-• -
=r-7i T
• ^L_
ANNULAR OVERFLOW WEIR
*. * 1 V- • . ' .
• /. LIQUID
*• WFLOW .'
OUTLET LIQUID
•SETTLING PARTICLES
REVOLVING COLLECTION
MECHANISM
SETTLED PARTICLES
COLLECTED AND PERIODICALLY
REMOVED
SLUDGE DRAWOFF
Figure VII-7
REPRESENTATIVE TYPES OF SEDIMENTATION
314
-------
ZQ;
UJ UJ
UJ
z
<£
CC
«s
0.
UJ
CO
00
I
•H
315
-------
oo
w
o
<#
CM
CO
CO
Hjz;
£? o
•^ H
oja
H H
X O
oia
-------
c: o
o*
w UJ
0.
O UJ
H- 03
CC
O
I
I
H
H
i-i
a
o
UJ
u_
i-
UJO
317
w
o
M
s
1
B
H
W
Hi
cn
,-4
g
Si
H-J
ptl
-------
I I
1 1
1 1
-T- ! . .1.
W
©
CM
II
ob
be
Concentration
Raw Wa
Cad
EFFECTIVENESS
ENTAT
5M
B*l
sssl
= 1
YDROXIDE PREC
tration
in
e
ns.
(l/Gui) uoijEHU33uo3 mating paieajj. uiniwpeo
318
Data points with a taw waste con
less than 0.1 mg/i were not includ
treatment effectiveness calculatio
-------
t i
L 1
(
1
I
|
I
I
i
1
i
i i
!
i
t
1
:
1
i
i
1
(
^
)
t
f
W
i
I
i
!
1
©
7>
<"
!
i
i
)
!
|
!>
^v
i
i
!)
)MM
O
uu
«^» i^
|> LU
-5. 2
s O
£ =
2/-vi <£
Ol ^
S ^ ^
g i S s
g = S =3
o « > a I
•• s uu ^y o
S si w si
5 ' =92 =
> ea o cj
1 ^^
« 1
=. S:
'5 u
1 £
" -5
a
X
a
a
o a
v~ >•
—
(j/liui) UOUE41U30U03
319
-------
I
1
©
1
I
^
0
©
r—
•
*
3
©
2 o «-:
1- O
(|/6iu) uoiiBJiusauoQ iuaniyg ps^eajj^ jaddoj
f ' •' "'•"•"
(
0"
<3
a srs
ii
M . .
g
53
"o
e>
5
§ s s
" a
UJ
>
to
Concentration (my/!)
VH-13
IDSMEWTATIOK EFFECT
'PER
3 cc « o
IS a ss «
a> ca o
1 1.0
Copper Raw 1
Fl
HYDROXIDE PRECIPITATI
'•• "-^ o
»»
e
o
320
-------
1
•
J L
0
o ^»»
u
w«
£
«*•
|
3
'""
a
U5
UJ
at
>
ui
u.
u.
2
UJ UU
c- w
=3 a
09 O
O.
01
s
X
o
a
>•
.-s
321
-------
<•*) —
—. IS)
If II
c/t «
§ i
e e
2 2
§ 3
SB .2
I |
2 I
e g
8 <5
§ £
o j
3 S
% 3
"3 '£
•3 i
iz <
© x
UU
S
LU
UU
u.
LL.
UJ
1s
t =>
< 3
a <
O —I
LU
ec
a.
LU
a
x
o
c
a
s-
(l/fiui) UOIJEJW130U03
(l/fiw) UOI1EJWJ30UOO
©
x
322
-------
< I I
<£>
I . I
©
©
0
©
©
©
CS
C3
sn
04
—
c
S-
«3
S
os
^- C
I
i
u
«/5
UJ
UJ
>
UJ
a
O
** 5 "
UJ W S
CS O
U. H
cz
a.
LU
X
a
cc
a
323
-------
I I I
1 I
III I I
I I
©
©
©
©
©
©
0
©
SB
est
II
vt
_3
to
1
S
o
Oi
_o
ra
s
as
3
LU
u
LU
LU
z
p
>—
cc ^
=5 2
ea o
£
UJ
Q
X
ra
c:
a
>
324
-------
§
5
tn
va
UJ
S
UJ
UJ
u.
LL.
UU
O
00 <
s
u
i
m
CC
2 uj-
UJ C/5
11
u. t-
u
UJ
c
X
O
(I/Bui) uoi;ami3ouoo
pajB3Ji
325
-------
cc
V)
LU
UJ
u.
u.
S
tn
o
I
cu
a.
UJ
o
X
a
cz
c
326
-------
CM
I
H
H
>
GO
327
-------
FLANGE
WASTE WATER
INFLUENT
DISTRIBUTOR
WASH WATER
SURFACE WASH
MANIFOLD
BACKWASH
BACKWASH
REPLACEMENT CARBON
CARBON REMOVAL PORT
TREATED WATER
SUPPORT PLATE
Figure VII-21
ACTIVATED CARBON ADSORPTION COLUMN
328
-------
OILY WATER
INFLUENT
WATER
DISCHARGE
OVERFLOW
SHUTOFF
VALVE
EXCESS
AIR OUT
LEVEL
CONTROLLER
TO SLUDGE
TANK
Figure VII-22
DISSOLVED AIR FLOTATION
329
-------
CONVEYOR DRIVE
i— BOWL. DRIVE
ig DRYING
ZONE
SLUDGE
INLET
CYCLOGEAR
IMPELLER
Figure VII-23
CENTRIFUGATION
330
-------
I
H
H
(0
I
331
-------
CONTROLS
OZONE
GENERATOR
DRY AIR
PH]
OZONE;
REACTION
TANK !
-{X}-
TREATED
WASTE
RAW WASTE-
Figure VII-25 '
TYPICAL OZONE PLANT FOR WASTE TREATMENT
332
-------
MIXER
WASTEWATER
FEED TANK
PIF
ST,
SE
ST
J_
Ul ,
!ST i
*GE j
3
to
:OND §.
AGE 3
3!
THIRD jj
STAGE 3
T s
I
CHJ
4 PUMP
TREATED WATE
c
U.
'
C
e=
II
R
— EXHAUST
C
*1
GAS
TEMPERATURE
CONTROL
— — PH MONITORING
\
I
3
| |
I L
C
1 1
i
TEMPERATURE
CONTROL
PH MONITORING
TEMPERATURE
- — — CONTROL w
— PH MONITORING
OZONE
OZONE
GENERATOR
Figure VII-26
TJV/OZONATION
333
-------
<£
O
I-
<
s
o
a.
u
u
h.
U.
Ill
ffl
3
0
a
H
>
-------
CONDUIT
TO MOTOR
INFLUENT »-»•-
CONDUIT TO
OVERLOAD
ALARM
EFFLUENT PIPE
EFFLUENT CHANNEL
PLAN
INFLUENT
CENTER COLUMN
CENTER CAGE
WEIR
SQUEEGEE
STILTS
CENTER SCRAPER
SLUDGE PIPE
Figure VII-28
GRAVITY THICKENING
335
-------
WASTE WATER CONTAINING
DISSOLVED METALS OR
OTHER IONS
REGENERANT TO REUSE,
TREATMENT, OR DISPOSAL
OIVERTER VALVE
DISTRIBUTOR
REGENERANT
SOLUTION
SUPPORT
-DIVERTER VALVE
METAL-FREE WATER
FOR REUSE OR DISCHARGE
Figure VII-29 ;
ION EXCHANGE WITH REGENERATION
336
-------
o
MACROMOLECULES
<| AND SOLIDS
MEMBRANE
A? - 450 PSl
WATER
FEED
PERMEATE (WATER)
MEMBRANE CROSS SECTION.
IN TUBULAR, HOLLOW FIBER,
OR SPIRAL-WOUND CONFIGURATION
CONCENTRATE
(SALTS)
O SALTS OR SOLIDS
O WATER MOLECULES
Figure VII-30.
SIMPLIFIED REVERSE OSMOSIS SCHEMATIC
337
-------
PERMEATE
TUBE
FEED
FLOW
FEED
O-RING —
ADHESIVE BOUND
SPIRAL MODULE
CONCENTRATE
FLOW
BACKING MATERIAL
MESH SPACER
• M EMBRANE
SPIRAL MEMBRANE MODULE
SNAP
RING
"O" RING
SEAL
FEED ..
<=£>
PRODUCT WATER
POROUS SUPPORT TUBE PERMEATE FLOW
WITH MEMBRANE J i
.•.IBRACKISH
WATER
FEED FLOW
PRODUCT WATER
TUBULAR REVERSE OSMOSIS MODULE
BRINE
CONCENTRATE
FLOW
EPOXY
TUBE SHEET
OPEN ENDS
OF FIBERS
CONCENTRATE
OUTLET —FLOW SCREEN
-END PLATE
POROUS FEED
DISTRIBUTOR TUBE
POROUS
BACK-UP DISC
SNAP
RING
PERMEATE
END PLATE
HOLLOW FIBER MODULE
Figure VII-31
REVERSE OSMOSIS MEMBRANE CONFIGURATIONS
338
-------
A
Lc
' L. J-«
IT
jj
3 It C
ii
i
!|
1 1
i
ii
3 II H
II
6-IN. VITRIFIE
* Li U "<•
Tf
j r
3 C
I
JL
ID PIPE LAID— '
WITH PLASTIC JOINTS
b i| t
ii
ii
1!
Ii
3 |! C
il
r- SPLASH BOX
\ 1 1 _.._
\ II P
^> r—i
t !
I
i
i
i
SJ ' h
1
i ^
iiitr
r-C - -_ LT-t
ir
it
2 1'
« !!
a. « II
iijj
\\\\
> ° ii
? 5tH h
i 3 ||
J^,
~^^ '
| 1
3 l| C
i!
? Ii Q
j L! =u -
ir
!
1
r il c
II
II
ii
H
) H [
il
~~~lf
1 1
i '
i|
jj
H i
6-IN. FLANGED ||
X^\~SHEAR GATE 1.
\||
H
1 1
h
Q
-Mil
A
PLAN W \
/-6-IN. FINE SAND wlTl"*1"*"*
3-IN. FINE GRAVEL
3-IN. MEDIUM GRAVEL
3 TO 6 IN. COARSE GRAVEL
PIPE COLUMN FOR
GLASS-OVER
3-IN. MEDIUM GRAVEL
S-IN. UNDERDRAIN LAID-
WITH OPEN JOINTS
SECTION A-A
Figure VII-32
SLUDGE DRYING BED
339
-------
UUTRAFILTRATION
P * 10-50 PSI
MEMBRANE
WATER SALTS
•MEMBRANE
PERMEATE
• •
-••
* o • • *o»»°»wo»*
:ED *Q * O . * • • • « *Q * O * CONCENTRATE
• O • o • ° • . ° • • • O 6 • . 0.0
O • • n
°.
FEED *Q
' 1 ' * •
O OIL PARTICLES
• DISSOLVED SALTS AND LOW-MOLECULAR-WEIGHT ORCANICS
Figure VII-33
SIMPLIFIED ULTRAFILTRATION FLOW SCHEMATIC
340
-------
<
LU
s
en
LU
O.
SJ
KZ
ii
go
. e:
o
->
PROCESS
iZ 03
-'X
cc
LU
O
LU
QC
LU
d O
o ;z
LU cr
UJ <£
cr QL
u- y
LU
LU
tr
u.
o
LU
(f)
t
•z. dL
LU O = j
Q.' Z S —
CO < LU O
H
M
0)
H
CQ
O
H
H
H
v4
H
Ed
-------
FABRIC OR WIRE
FILTER MEDIA
STRETCHED OVER
REVOLVING DRUM
DIRECTION OF ROTATION
ROLLER
VACUUM
SOURCE
SOLIDS SCRAPED
OFF FILTER MEDIA
SOLIDS COLLECTION
HOPPER
STEEL
CYLINDRICAL
FRAME
LIQUID FORCE
THROUGH
MEDIA BY
MEANS OF
VACUUM
INLET LIQUID
TO BE
FILTERED
-TROUGH
FILTERED LIQUID
Figure VII-35
VACUUM FILTRATION
342
-------
EVAPORATION
)
CONTACT COOLING
WATER
COOLING
TOWER
RECYCLED FLOW
SLOWDOWN
DISCHARGE
MAKE-UP WATER
Figure VII-36
FLOW DIAGRAM FOR RECYCLING WITH A COOLING TOWER
343
-------
SINGLE RINSE
OUTGOING WATER
WORK MOVEMENT
INCOMING WATER
DOUBLE COUNTERFLOW
RINSE
OUTGOING WATER
WORK
--••MOVEMENT
INCOMING WATER
TRIPLE COUNTERFLOW
RINSE
WORK MOVEMENT
,-*•—+.—,
r^r-trf
— r
J I 1Q
O
i
\
INCOMING
r- WATER
OUTGOING WATER
Figure VII-37
COUNTER CURRENT RINSING (TTANKS)
344
-------
10001—
750
500
S
o
"«
ca
250
Rinse Stages
Figure VII-38
EFFECT OF ADDED RINSE STAGES ON WATER USE
345
-------
VII-1 ;
j
pH CONTROL EFFECT ON METALS REMOVA£
Day 1
In Out:
Day 2
In Out
Day 3
In Out
pH Range
(mg/1)
TSS
Copper
Zinc
2.4-3.4 8.5-8.7 1.0-3.0 5.0-6.0 2.0-5.0 6.5-8.1
39
312
250
8
0.22
0.31
16
120
32.5
1,9
5.12
25.0
16
107
43.8
7
0.66
0.66
346
-------
Table VII-2
EFFECTIVENESS OF SODIUM HYDROXIDE FOR METALS REMOVAL
Day 1
In Out
Day 2
In Out
Day 3
In Out
pH Range
(mg/1)
Gr
Cu
Fe
Pb
Mn
Ni
Zn
TSS
2.1-2.9
0.097
0.063
9.24
1.0
0.11
0.077
0.054
9.0-9.3
0.0
0.018
0.76
0.11
0.06
0.011
0.0
13
2.0-2.4
0.057
0.078
15.5
1.36
0.12
0.036
0.12
8.7-9.1
0.005
0.014
0.92
0.13
0.044
0.009
0.0
11
2.0-2.4
0.068
0.053
9.41
1.45
0.11
0.069
0.19
8.6-9.1
0.005
0.019
0.95
0.11
0.044
0.011
0.037
11
347
-------
Table VII-3
Al
Co
Cu
Fe
Mn
Nl
Se
Ti
Zn
EFFECTIVENESS OF LIME AND SODIUM HYDROXIDE
FOR METALS REMOVAL
In
Day 1
Out
pH Range 9.2-9.6 8.3-9.8
(mg/1)
37.3
3.92
0.65
137
175
6.86
28.6
143
18.5
0.35
0.0
0.003
0.49
0.12
0.0
0.0
0.0
0.027
In
Day 2
Out
9.2
38.1
4.65
0.63
110
205
5.84
30.2
125
16.2
7.6-8.1
0.35
0.0
0.003
0.57
q.o
i
0.0
Q.O
i
0.044
In
Day 3
Out
9.6
29.9
4.37
0.72
208
0.012 245
5.63
27.4
115
17.0
7.8-8.2
0.35
0.0
0.003
0.58
0.12
0.0
0.0
0.0
0.01
TSS
4,390
3,595
13
2,805
13
348
-------
Table VII-4
THEORETICAL SOLUBILITIES OF HYDROXIDES AND SULFIDES
OF SELECTED METALS IN PURE WATER
Metal
Cadmium (Cd++)
Chromium (Crl I-1)
Cobalt (Co++)
Copper (Cu++)
Iron (Fe++)
Lead (Pb++)
Man gane s e (Mn-H-)
Mercury (Hg-H-)
Nickel (Ni++)
Silver (A§+)
Tin (Sn-H-)
.Zinc (Zn++)
Solubility of Metal Ion, mg/1
As Hydroxide
2.3 x 10-5
8.4 x 1
-------
CO
s
w
H
CO
&
§
w
i
jz;
a)
T3
•H
M -u
o co
cj
««
PC -
O CO
a}
m m co
o o o i
o o o i
I
o
o
CO
*
CO
o
o
W)
1
H
H
>
-^
O
CO
S
g
g
<5
E-i
<5
Q
O
S5
l-l
H!
fc
3
A
0)
4J M
K*% oi
«rH 4J
CO O r-l
dj j~i ^
JS4 JJ N
O
*k 0) *
Q) tH QJ
a »4J
n4»-< -W
O <1)
PM CO
4J
r-3
O
H
o
CO CM
CO O
• *
h-. o
V
CM
CM
r*^ ^?
A
(1)
4-J ^
«r-1 4J
CO Oi-I
(U M «H
fV| 4J |xj
O
«OJ .
0) r-< Q)
S <1) r-i
•H f^-P
. 1 i— J ,JJ
O (U
Pk CO
4->
O
£^
H
^
O> r-l
1 0
CO
o
V
CO
vO
1 vO
O
«O CM
I— 1
•
o
V
•
CM
«^f
O
•
O
V
CO
CM
CO
1 \0
1 •
0
I
co
o
1— 1
o
i-H
1 .
I O
CM
IT)
| •
1 O
tH «-»
O 0*
V V
CO
vo a\
O CO
co
i"
i^.
o
i •
I O
1
I'
\Jf\
1 1 .
i ON
CO
CO
Treatme;
I?
£C S
&• ^
vo
o
M
a
o
-------
Table VII-6
SULFIDE PRECIPITATION-SEDIMENTATION PERFORMANCE
Parameter
Cd
Cr (Total)
Cu
Pb
Hg
Ni
Ag
Zn
Treated Effluent (mg/1)
0.01
0.05
0.05
0.01
0.03
0.05
0.05
0.01
351
-------
Table VII-7
FERRITE CO-PRECIPITATION PERFORMANCE
Metal
Mercury
Cadmium
Copper
Zinc
Chromium
Manganes e
Nickel
Iron
Bismuth
Lead
Influent (mg/1)
7.4
240
10
18
10
12
1,000
600
240
475
Effluent (mg/1)
0.001
0.008
0.010
0.016
<0.010
0.007
0.200
0.06
0.100
0.010
352
-------
Table VII-8
CONCENTRATION OF TOTAL CYANIDE (mg/1)
Plant
1057
Method
FeS04
33056
12052
FeS04
In
2.57
2.42
3.28
0.14
0.16
0.46
0.12
Mean
Out
0.024
0.015
0.032
0.09
0.09
0.14
0.06
0.07
353
-------
Table VII-9 ,
MULTIMEDIA FILTER PERFORMANCE
Plant ID # TSS Effluent Concentration, mg/1
06097 0.0, 0.0, 0.5 !
13924 1.8, 2.2, 5.6, 4.0, 4.6, 3.0, 2.2, 2.8
3.0, 2.0, 5.6, 3.6, 2.4, 3.4
18538 1.0
30172 1.4, 7.0, 1.0
36048 2.1, 2.6, 1.5
•Mean 2.61
354
-------
0>
H
CO
S
W
H
CO
JM
CO
O
e
M
. T
H
H
W
co
Q
H
O
M
hH
Ed
CO
En
O
W
O
5
M
a
N-w'
O
H
3
EH
%%
w
S3
0
U
CO
o
H
j i
O
CO
G
W
Q
W
p i
C/3
J3
CO
en
Q
•U
<§'
Ci
HI
m m t rt
-------
Table VII-11
I
SKIMMING PERFORMANCE
Plant Skimmer Type
06058 API
06058 Belt
Oil Sc Grease (mg/1)
In Out
224,669 17.9
•19.4 8.3
356
-------
Table VII-12
SAMPLING DATA FROM COPPER FORMING PLANTS WHICH PRACTICE
OIL SKIMMING AND ACHIEVE EFFLUENT OIL AND GREASE
CONCENTRATIONS OF 20 mg/1 OR LESS
Influent
Plant Oil and Grease TTO
6058 53,800 166.2
.395,538 0.51
47432 7,070 10.39
1,004 -0.11
Effluent
Oil and Grease TTO
16.3 0.02
13.3 0.31
15 0.04
5 0.01
357
-------
Table VII-13
CHEMICAL EMULSION BREAKING EFFICIENCIES
Parameter
O&G
TSS
O&G
TSS
O&G
TSS
O&G
Concentration (mg/1)
Influent
6,060 .
2,612
13,000
18,400
21,300
540
680
1,060
2,300
12,500
13,800
1,650
2,200
3,470
7,200
Effluent
98
46
277
--
189
121
59
140
52
27
18
187
153
63
80
Reference
Sampling data*
Sampling data+
Sampling data**
Katnick and Pavilcius, 1978-H-
*0il and grease and total suspended solids were taken as grab
samples before and after batch emulsion;breaking treatment which
used alum and polymer on emulsified rolling oil wastewater.
•KDil and grease (grab) and total suspended solids (grab) samples
were taken on three consecutive days from emulsified rolling
oil wastewater. A commercial demulsifier was used in this batch
treatment.
**0il and grease (grab) and total suspended solids (composite)
samples were taken on three consecutive days from emulsified
rolling oil wastewater. A commercial demulsifier (polymer)
was used in this batch treatment.
HHKEhis result is from a full-scale batch chemical treatment system
for emulsified oils from a steel rolling mill.
358
-------
Table VII-14
COMBINED METALS DATA EFFLUENT VALUES (mg/1)
Cd
Cr
Cu
Pb
Ni
Zn
Fe
Mn
TSS
Mean
0.079
0.08
0.58
0.12
0.57
0.30
0.41
0.21
12.0
One- Day
Max.
0.32
0.42
1.90
0.15
1.41
1.33
1.23
0.43
41.0
10-Day Avg.
Max.
0.15
0.17
1.00
0.13
1.00
0.56
0.63
0.34
20.0
30-Day Avg.
Max .
0.13
0.12
0.73
0.12
0.75
0.41
0.51
0.27
15.5
359
-------
Pollutant
Sb
As
Be
Hg
Se
Ag
Th
Al
Co
F •
Table VII-15
LScS PERFORMANCE
ADDITIONAL POLLUTANTS
Average Performance (mg/1)
0.7
0.51
0.30
0.06
0,30
0.10
0.50
l.'ll
O.|05
14 J5
360
-------
Table VII-16
COMBINED METALS DATA SET - UNTREATED WASTEWATER
Pollutant
Cd
Cr
Cu
Pb
Ni
Zn
Fe
Mn
TSS
Min. Cone, (mg/1.)
4.6
Max. Cone, (mg/1)
3.83
116
108
29.2
27.5
337.
263
'5.98
4,390
361
-------
Table VII-17
MAXIMUM POLLUTANT LEVEL IN UNTREATED WASTEWATER
ADDITIONAL POLLUTANTS
Cmg/1)
Pollutant
As Sc Se
Be
Ag
As
Be
Cd
Cr
Cu
Pb
Ni
Ag
Zn
F
Fe
O&G
TSS
4.2
0.18
33.2
6.5
3.62
16.9
352
10.24
8.60 0.23
1.24 110.5
0.35 ( 11.4
100
; 4.7
0.12 1,512
646
16
796 587.8
22.8
2.2
5.35
0.69
760
2.8
5.6
362
-------
0! >
CD
+ Q
d i •
0) J-)
o cooo m
rH O-sJ-CO
dodo
y
vo
CO
i-i
-§
H
W
O
!2
§
O
_^
w
PH
/~\
fe
UJ
CO
O
W
EH *s$
^H
3
CQ
cd
T3
0)
4-1
cd
(1)
M
EH
t
00
^^
^^\
rH
±4
0
O
O rH
rH O
OO
+ 1+
vO
VO rH
OO
OO
m
Of**L
<~>
OO
C t
rH O
OO
O O
r-~ oo
TH *"
o C
rH CO rH
OOO
+ 1+ 1+ 1
O CO ON
CM CM
>
^
0^000
oj o o 01 in
r^* CNJ co ON
1 1 t t t
oo m
O O^O CN O
CN O rH CO O
CO CO rH
minimum
J-l ^ *H ti 0)
U O & M fe
363
-------
o\
1
HI
H
<1)
rH
H
ORMANCE
W
X-N
fa
. U>
CO
H?
S-'
(23
O
H
EH M
fa &*
O
J3
t-i
^
CM >
CU
(3 •
ct) 13
cu -U
t£ co
•
. >
4-ld)
C
ca •
S-u
CO
rH
a
i— i -3- co o
O O r-l O CM
OOOOO
o co oo-d- vo
Is- CM O CM Is-
O O rHO i-l
1 t t S t
OOOOO
ooooo
in-n- o oo CM
i rH O VO i-H -H;
O O O O r-H
i
in vo r-i in o\
in I-H I-H -H- o
o o CM o in
, ooooo
+ 1+ 1+ 1+ 1+ 1
00 i— 1 -H; in CM
CO I-H 00 co O
O O rH O-H-
ooooo
1
;
vo cooo vo in
m CM 00 VO rH
O O rH O CO
1 t I 1 1
ooooo
1 CD CD CD oo
O Is- CO
ON i-H CO -H-
in o co CM
CM
in Is- ON ON
rH CM 00 CO ON
• • * • •
cr> o <}• co in vo
cO
rH
f-l
O
fa
.
in vo in m
364
-------
0
CM
1
H
M
rH
f^S
jrt
H
W
CJ
^
O
w
P-I
_ifc
Pu
CO
$23
O
M
H 0
M H
£_l £2
• ^ «^
i_4 j_j
b PM
O
g
M
jh|
w
CO
1
&
0
r_j
4
H
fl
p
0
-------
CM
I
H
0)
rH
cd
&
<0
4J
CO
r"*!
CO
>,
00
O
o
C
0)
H
UJ
CO
jj]
a
•U
0]
r*
CO
t*
bX
O
rH
O
C
•g
> bC
i *^i *•*<*
O 0 ^
CO Q
^H (Z^ *^4
1 •
d> >•>!. o> co
CO O CM
CM CM rH
O rH O
r^. m co
000
,a oo CD
co -
CM O O
OOO
LO C^ VO
P**- »
O in rH
rH O O
rH CO rH
O vO
rH
rH CO
CM O
00-
c
iS f^4
0 0
o o
rH T— I
00
O CM
rH rH
OO
o m
rH rH
vo
CM
o m
o m
rH rH
0 0
CM O
rH CM
o o
O rH
CM -
-------
Table VII-22
TREATABILITY RATING OF PRIORITY POLLUTANTS UTILIZING
CARBON ADSORPTION
Priority Rallutant
•Removal Rating
Priority Pollutant
*Rgnpval Rating
1. acenaphthene H
2. acrolein !•
3. acrylonitrile . L
4. benzene M
5. benzidine H
6. carbon tetrachloride K
(tetrachloromethane)
7. chlorobenzene H
8. 1,2,4-trichlorobenzene H
9. hexachlorobenzene B
10. 1,2-dichloroethane M
11. 1,1.1-trichlorcethane M
12. hexachlorcethane B
13. 1,1-dichloraethane M
14. 1,1,2-trichlorcethane M
IS. 1,1,2,2-tetrachloroethane H
16. cnloroethane l>
17. bis(chloromethyl)ether
18. bis(2-chloroethyl)ether M
19. 2-chlotoethyl vinyl ether L
(mixed)
20. 2-chloronaphthalene H
21. 2,4,6-trichlorqphenol H
22. parachlorometa cresol H
23. chloroform (trichloronethane) L
24. 2-chlorophenol H
25. 1,2-dichlorobanaene H
26. 1,3-dichlorobenzene 'H
27. 1,4-dichlorobenzene H
28. 3,3'-dichlorcbenzidine H
29. 1,1-dichloroethylene I.
30. 1,2-trans-dichloroethylene L
31. 2,4-dichlorophenbl H
32. 1,2-dichlorcpropane M
33. 1,2-dichloroprcpylene M
(1,3,-dichloropr openfc j
34. 2,4-dimethylphenol H
35. 2,4-dinitrotoluene H
36. 2,6-dinitrotoluene B
37. 1,2-diphenylhydrazine H
38. ethylbenzene M
39. Eluoranthene B
40. 4-chlorophenyl fhenyl ether H
41. 4-bronophenyl phenyl ether B
42. bis(2-chloroisopropyl)ether M
43. bis(2-chloroethoxy)niethane M
44. nethylene chloride L
(dichloromethane)
45. methyl chloride (chlorcmethane) L
46. methyl bromide (brcnrxnethane) L
47. bromofornt (tribronomethane) H
48. dichlorcbroncnethane M
49. trichlorofluoromethane M
50. dichlorodif luut methane L
51. chlorcdibrcnanethane M
52. hexachlorobutadiene H
53. hexachlorocyclopentadiene B
54. iaophorone ' B
55. naphthalene B
56. nitrobenzene H
57. 2-nitrophenol H
58. 4-nitrophenol B
59. 2,4-dinitroFhenol B
60. 4,6-dinitro-o-cresol B
61. N-nitrosodiitethylamine M
62. N-nitroaodiphenylaraine H
63. »^itroscdi-n-propylamine M
64. pentachlorophenol B
65. phenol M
66. bis(2-ethylhexyl)phthalate B
67. butyl benzyl phthalate B
68. di-n-butyl phthalate H
69. di-n-octyl phthalate B
70. diethyl phthalate B
71. dimethyl phthalate B
72. 1,2-benzanthracene (benzo B
(a)anthracene)
73. benzo(a)pyrene (3,4-benzo- B
pyrene)
74. 3,4-benzofluoranthene B
(benzo(b)fluoranthene)
75. 11,12-benzofluoranthene • H
(benzo(k)fluoranthene)
76. chrysene B
77. acenaphthylene B
78. anthracene H
79. 1,12-benzoperylene (benzo H
(ghi)-perylene)
80. fluorene B
81. phenanthrene B
82. 1,2,5,6-dibenzathracene B
(dibenzo (a,h) anthracene)
83. indeno (1,2,3-cd) pyrene H
(2,3-o-phenylene pyrene)
84. pyrene -
85. tetrachloroethylene M
86. toluene H
87. trichlorcetnylene L
88. vinyl chloride L
{chloroethylene)
106. FCB-1242 (Arochlor 1242) B
107. FCB-1254 (Arochlor 1254) B
108. PCB-1221 (Arochlor 1221) B
109. PC&-1332 (Arochlor 1232) B
110. FCB-1248 (Arochlor 1248) B
111. PC&-1260 (Arochlor 1260) B
112. FCB-1016 (Arochlor 1016) B
• NOTE; Explanation of Removal RAtings
Category B (high removal)
adsorbs at levels >^ 100 mg/g carbon at C- » 10 mg/1
adsorbs at levels 2. 100 fg/g carbon at C| < 1.0 mg/1
Category H (moderate renewal)
adsorbs at levels > 100 mg/g carbon at Cf
adsorbs at levels <_ 100 mg/g carbon at
Category L (low renewal)
adsorbs at levels < 100 mg/g carbon at C£
10 ng/1
1.0 mg/1
10
adsorbs at levels < 10 mg/g carbon at Cf < 1.0 ag/1
final concentrations of oriority pollutant «t equilibrium
367
-------
Table VII-23
CLASSES OF ORGANIC COMPOUNDS
Organic Chemical Class
Aromatic Hydrocarbons
Polynuclear Aromatics
Chlorinated Aromatics
Phenolics
Chlorinated Phenolics
High Molecular Weight Aliphatic and
Branch Chain Hydrocarbons
Chlorinated Aliphatic Hydrocarbons
High Molecular Weight Aliphatic Acids
and Aromatic Acids
High Molecular Weight Aliphatic Amines
and Aromatic Amines
High Molecular Weight Ketones, Esters,
Ethers and Alcohols
Surfactants
Soluble Organic Dyes
ADSORBED ON CARBON
Examples of Chemical Class
I •
benzene, toluene, xylene
i
naphthalene, anthracene
bephenyls
chlprobenzene, polychlorinated
biphenyls,- aldrin, endrin,
toxalphene, DDT
phenol, cresol, resorcenol
and Ipolyphenyls
I
tric|hlprophenol, pentachloro-
phenol
i
i
gasoline, kerosine
carbon tetrachloride,
perchloroethylene
i
i
tar pcids, benzoic acid
aniline, toluene diamine
i
i
i
hydroquinone, polyethylene
glycpl
i
alkyl benzene sulfonates
melkylene blue, Indigo carmine
High Molecular Weight includes compounds in the broad range of from 4 to 20
carbon atoms.
368
-------
Table VII-24
ACTIVATED CARBON PERFORMANCE
Type of
Industry
NFM
Foundries
NFM
NFM
NFM
NFM
NFM
Mean Pollutant Levels
ug/l_
Pollutant Parameter
Fluoranthene
N-nitrosodiphenylamine
Benzo(a)anthracene
Chrysene
Anthracene
Phenanthrene
Pyrene
In
Out
55
250
13
160
43
46
130
13
190
0.7
3.8
6.6
4.6
11
369
-------
Table VII-25
I
ION EXCHANGE PERFORMANCE
(All Values mg/1)
1
Parameter
Al
Cd
Cr-f-3
Cr+6
Cu
CN
Au
Fe
Pb
Mn
Ni
Ag
S04
Sn
Zn
Plan
Prior to
Purifica-
tion
5.6
5.7
3.1
7.1
4.5
9.8
--
7.4
—
4.4
6.2
1.5
--
1.7
14.8
t A
After
Purifica-
tion
0.20
0.00
0.01
0.01
0.09
0.04
__
0.01
--
0.00
0.00
0.00
--
0.00
0.40
i Plant
Prior to
Purifica-
tion
--
--
;
.
43.0
l: 3.40
'• 2.30
!
1.70
--
1.60
9.10
210.00
•«, ,"• ,« ',! I if •: ' J . ' i',.1
1.10
— —
B
After
Purifica-
tion
_ _
—
--
--
0.10
0.09
0.10
--
0.01
--
0.01
0.01
.2_.00
0.10
__
370
-------
Table VT.I-26
PEAT ADSORPTION PERFORMANCE
Pollutant
Cr+6
Cu
CN
Pb
Hg
Ni
Ag
Sb
Zri
Influent (mg/1)
35,000
250
36.0
20.0
1.0
2.5
1.0
2.5
1.5
Effluent (mg/1)
0.04
, 0.24
0.7
0.025
0.02
0.07
0.05
0.9
0.25
371
-------
CM
M
H
t^
OJ
5
EH
EH
Z
w
O
. T
£
ft*
H
s
w
EH
CO
£
o
M
EH
3
EH
|J
H
Pn
W
«
s
Ed
S
^
tN V^
o
_j
^^
CO
4J
G
^
H
JJ
vo d
vo O
***' VM/
o
rH
JJ
c
rH
ftj fjj
H
CO
»
!-i
-------
Table VII-28
ULTRAFILTRATION PERFORMANCE
Parameter
Oil (freon
ext r act ab le )
COD
TSS
Total Solids
Feed (mg/1)
95
1,540
1,230
8,920
791
1,,262
5,676
1,380
2,900
Permeate (mg/1)
22*
52*
4
148
19*
26*
13*
13
296
*From samples at aluminum forming Plant B
373
-------
-------
SECTION VIII
COST OF WASTEWATER TREATMENT AND CONTROL
This section presents estimates of the costs of implementing the
major wastewater treatment and control technologies described in
'Section VII. These cost estimates, together with the estimated
pollutant reduction performance for each treatment and control
option presented in Sections IX, X, XI, and XII provide a basis
for evaluating the options presented and identification of the
best practicable technology currently available (BPT), best
available technology economically achievable (BAT), best demon-
strated technology (BDT), and the appropriate technology for
pretreatment. The cost estimates also provide the basis for
determining the probable economic impact on the copper forming
category of regulation at different pollutant discharge levels.
In addition, this section addresses non-water quality environ-
mental impacts of wastewater treatment and control alternatives,
including air pollution, solid wastes, and energy requirements.
In developing the cost estimates presented in this section, EPA
selected specific wastewater treatment technologies and
in-process control techniques from among those discussed in
Section VII and combined them in wastewater treatment and control
systems. Investment and annual costs for each system were
estimated based on wastewater flow rates and raw waste
characteristics as presented in Section V.
COST ESTIMATES FOR INDIVIDUAL TREATMENT TECHNOLOGIES
Introduction
Treatment technologies have been selected from among the larger
set of available alternatives discussed in Section VII on the
basis of an evaluation of raw waste characteristics, typical
plant characteristics (e.g., location, production schedules,
product mix, and land availability), and present treatment prac-
tices. Specific rationale for selection is addressed in Sections
IX, X, XI, and XII. Cost estimates for each technology addressed
in this section include investment costs and annual costs for
depreciation, capital, operation and maintenance, and energy.
The basic cost data came from several sources. Some of the data
were obtained during on-site surveys. Other data were obtained
through discussions with waste treatment equipment manufacturers.
375
-------
The specific assumptions for each wastewater treatment process
are listed under the subheadings to follow. Costs are presented
as a function of influent wastewater flow rate except where noted
in the process assumptions.
Costs are presented for the following control and treatment
technologies: '
i
Lime Precipitation and Clarification>
Vacuum Filtration,
- Oil Skimming
Chemical Emulsion Breaking, ;
Chromium Reduction,
Spray Rinsing,
- Recycle-Cooling,
Contract Hauling, and i
- Multimedia Filtration. [
i
Investment. Investment is the capital expenditure required to
bring the technology into operation. If the installation is a
package contract, the investment is the purchase price of the
installed equipment. Otherwise, it includes the equipment cost,
cost of freight, insurance and taxes, and installation costs.
Total Annual Cost. Total annual cost is the sum of annual costs
for depreciation, capital, operation and maintenance (less
energy), and energy (as a separate function).
Depreciation. Depreciation is an allowance, based on tax regula-
tions, for the recovery of fixed capital from an investment to be
considered as a non-cash annual expense. It may be regarded as
the decline in a value of a capital asset due to wearout and
obsolescence.
Capital. The annual cost of capital is the cost, to the plant,
of obtaining capital expressed as an interest rate. It is equal
to the capital recovery cost (as previously discussed on cost
factors) less depreciation.
Operation and Maintenance. Operation and maintenance cost is the
annual cost of running the wastewater treatment equipment. It
includes labor and materials such as waste', treatment chemicals.
As presented in the tables, operation and maintenance cost does
not include energy (power or fuel) costs. These costs are shown
separately.
Energy. The annual cost of energy is shown separately, although
it is commonly included as part of operation and maintenance
cost. Energy cost has been shown separately because of its
importance to the nation's economy and natural resources.
376
-------
Cost Factors and Adjustments
As previously indicated, costs are adjusted to a common dollar
base and are generally influenced by a number of factors. These
cost adjustments and factors are discussed below.
Dollar Base - A dollar base of January 1978 was used for all
costs.
Investment Cost Adjustment - Investment costs were adjusted to
the January 1978 dollar base by use of the Sewage Treatment Plant
Construction Cost Index. This index is published monthly by the
EPA Division of Facilities Construction and Operation. The
national average of the Construction Cost Index for January 1978
was 288.0. Within each process, the investment cost was usually
defined as some function of the unit size capacity, usually
influent flow rate. ,
Supply Cost Adjustment - Supply costs such as chemicals were
adjusted to the January 1978 dollar base by the Wholesale Price
Index. This figure was obtained from the U.S. Department of
Labor, Bureau of Labor Statistics, "Monthly Labor Review." For
January 1978 the "Industrial Commodities" Wholesale Price Index
was 201.6. Process supply and replacement costs were included in
the estimate of the total process operating and maintenance cost.
Cost of Labor - For operation and maintenance labor costs, the
hourly wage rate for non-supervisory workers in water, steam, and
sanitary systems was used. This rate was obtained from the U.S.
Department of Labor, Bureau of Labor Statistics Monthly publica-
tion, "Employment and Earnings." For January 1978, this wage
rate was $6.00 per hour. This wage rate was then applied to
estimates of operation and maintenance man-hours within each
process to obtain process direct labor charges. To account for
indirect labor charges, 15 percent of the direct labor costs was
added to the direct labor charge to yield estimated total labor
costs. Items such as Social Security, employer contributions to
pension or retirement funds, and employer-paid premiums to
various forms of insurance programs were considered indirect
labor costs. '
Cost of Energy - Energy requirements were calculated directly for
each process. Estimated costs were then determined by applying
an electrical rate of 3.3 cents per kilowatt hour.
The electrical charge for January 1978 was determined through
consultation with the Energy Consulting Services Department of
the Connecticut Light and Power Company. This electrical charge
was determined by assuming that any electrical needs of a waste
377
-------
treatment facility or in-process technology would be satisfied by
an existing electrical distribution system; i.e., no new meter
would be required. This eliminated the formation of any new
demand load base for the electrical charge.
Items Not Included in Cost Estimates '
i
i
Items not included in the cost estimates include:
Administrative and laboratory facilities,
Garage and shop facilities, and
New land purchases.
\
Administrative and laboratory facility investment is the cost of
constructing space for administration, laboratory, and service
functions for the wastewater treatment system. For these cost
computations, it was assumed that there was already an existing
building and space for administration, laboratory, and service
functions. Therefore, there was no investment cost for this
item.
i
For the industrial waste treatment facilities being costed, no
garage and shop investment cost was included. This cost item was
assumed to be part «of the normal plant costs and was not allo-
cated to the wastewater treatment system.
No new land purchases were costed.. It was assumed that the land
required for the end-of-pipe treatment system was already avail-
able at the plant. !
i
System Cost Assumptions :
The costs presented in Figures VIII-1 through VIII-19 for waste-
water control and treatment systems do not'include system costs
associated with construction and operation* These system costs
are as follows: '•
Excess capacity (20 percent except clarification which
uses 40 percent);
Yard piping (20 percent);
Yardwork (14 percent);
Engineering (10 percent);
Contingencies (10 percent); and ;
Legal, fiscal, and administrative (1 percent).
These system costs must be added to the treatment module invest-
ment costs shown in Figures VIII-1 through!VIII-19. The excess
capacity factor is a multiplier on the size of the process to
account for shutdown for cleaning and maintenance.
378
-------
The yard piping and yardwork investment costs include the cost of
general site clearing, intercomponent piping, valves, overhead
and underground electrical wiring, cable, lighting, control
structures, manholes, tunnels, conduits, and general site items
outside the structural confines of particular individual plant
components. This cost is typically 9 to 18 percent of the
installed components investment costs. For these cost estimates,
an average of 20 percent for yard piping and 14 percent for
yardwork was utilized.
Engineering costs include both basic and special services. Basic
services include preliminary design reports, detailed design, and
office and field engineering services during construction of
projects. Special services include improvement studies, resident
engineering, soils investigations, land surveys, operation and
maintenance manuals, and other miscellaneous services. Engineer-
ing cost is a function of the investment cost for installed
equipment, yard piping, and yardwork.
Contingencies are unexpected costs which typically are incurred
during construction.
Legal, fiscal, and administrative costs relate to planning and
construction of wastewater treatment facilities and include such
items as preparation of legal documents, preparation of construc-
tion contracts, acquisition to land, etc. These costs are a
function of investment cost for process installed equipment, yard
piping, yardwork, engineering, and contingency costs.
Lime Precipitation and Clarification
Capital Cost - For continuous clarification with an influent flow
rate greater than or equal to 10,000 liters/hours (2,700 gallons/
hour), costs include a steel flocculator and its excavation, a
steel settling tank with skimmer and its excavation, and two
centrifugal sludge pumps. The capital costs for a continuous
system are shown in Figure VIII-1 (p.393 ). For influent flows
less than 10,000 liters/hour (2,700 galIons/hour), costs include
two above-ground conical unlined carbon steel tanks with a
retention time of four hours, and two centrifugal sludge pumps.
The capital costs for batch operation are shown in Figure VIII-2
(p.394 ). The capital costs for batch operation include $3,202
for sludge pumps. Figure VIII-3 (p.395 ) shows a comparison of
the capital cost curves for the modes discussed above.
The flocculator size is based on a 45-minute retention time, a
length to width ratio of 5, a depth of 2.44 meters (8 feet) and
includes a mixer.
379
-------
The settling tank is sized for a hydraulic loading of 600 liters/
hour/square meter (15 gallons/hour/sq. ft.), and a 4-hour reten-
tion time. Costs include motors, starters? alternators, and
necessary piping.
Chemical Cost - Lime is added for metals and solids removal. The
amount of chemical required is based on.equivalent amounts of
various pollutant parameters present in the stream entering the
treatment unit. The methods used in determining the lime
requirements are shown in Table VIII-1 (p.412 ).
i
i
Labor - Figure VIII-4 (p.396 ) presents the man-hour requirements
for the continuous clarifier system. For the batch system,
maintenance labor is assumed to be negligible and operation labor
is calculated from: :
(man-hours for operation)
390 + (0.975) (Ibs. lime added
!"'' '' " •''•"''•"per day)
Energy - The energy costs are calculated from the treatment and
sludge pump horsepower requirements. For the continuous mode the
horsepower requirement is assumed to be constant over the hours
of operation of the treatment system at a level of 0.0000265
horsepower per 1 gph of flow influent to the clarifier. The
sludge pumps are assumed to be operational for five minutes of
each operational hour at a level of 0.00212 horsepower per 1 gph
of sludge stream flow. I
For the batch mode the horsepower requirement is based on 7.5
minutes per operational hour at the following level:
Influent flow
Influent flow
1042 gph; 0.0048 hp/gph
1042 gph; 0.0096 hp/gph
The power required for the sludge pumps in!the batch mode is the
same as that required for the sludge pumps;in the continuous
mode. ;
i
Vacuum Filtration j
Capital Cost - Vacuum filtration costs are shown in Figure
VIII-5.Vacuum drum filtration units were sized based on a
typical loading of 14.6 kg of influent so lids/hour/sqiiare meter
of filter area (3 Ibs/ft2/hr.). The capital cost obtained from
this curve includes installation costs.
Alum and lime are added to sludges prior to filtration to provide
additional coagulation. All vacuum filtration costs are based on
data from a major manufacturer.
380
-------
Labor - The required operating hours per year varies with both
flow rate and the total suspended solids concentration in the
influent stream. Figure VIII-6 (p.398 ) shows the variance of
operating hours with flow and TSS concentration. Maintenance
labor for sludge disposal is fixed at 24 manhours per year.
Materials - The cost of materials and supplies needed for opera-
tion and maintenance includes belts, oil, grease, seals, and
chemicals required to raise the total suspended solids to the
vacuum filter. The amount of chemicals required is based on
raising the TSS concentration to the filter by 1 mg/1. Costs of
materials required as a function of flow and unaltered TSS
concentrations is presented in Figure VIII-7 (p.399 ).
Energy - Electrical costs needed to supply power for pumps and
controls are presented in Figure VIII-8 (p.400 ). Because the
required pump horsepower depends on the influent TSS level, the
costs are presented as a function of flow and TSS level.
Oil Skimming
Capital Cost - Oil skimming capital costs are shown in Figure
VIII-9. The costing analyses for the API Oil Skimming process
were based upon an optimization of the one channel oil separator
design by expanding the API design standards. The following
assumptions were used for costing purposes:
1. The unit was assumed to be an in-the-ground rectangular
cross-section concrete tank with a maximum horizontal
stream velocity set to the smaller of 3 fpm or 4.72
times the oil rise rate.
2. The depth-to-width ratio was maintained between
0.3 and 0.5 to minimize tank size.
3. The depth was maintained between 3 ft. minimum and
8 ft. maximum, and the width between 6 ft. minimum
and 20 ft. maximum to provide minimum tank size.
4. The costs were based on a 0.3 m (1 ft.) concrete
thickness and include the excavation required.
Flows up to 0.25 MGD are costed for a single unit; flows greater
than 0.25 MGD, require more than one unit.
Operation and Maintenance Costs. Only labor is included in the
operation and maintenance costs of the skimmer since other costs
were considered negligible in comparison. Figure VIII-10
(p.402 ) illustrates the correlation used to calculate the
381
-------
required marihours for operation and maintenance. The total
marihours are then multiplied by the $6.00 per hour labor rate
plus 15 percent indirect labor charge. Power costs were ignored
as they were negligible in comparison to all other operation and
maintenance costs. ,
,
Chemical Emulsion Breaking
i
Capital Cost - Chemical emulsion breaking costs are shown in
Figure VIII-11 as a function of the waste stream flow rate. Two
steel tanks are sized for a 6-hour retention time.
Costs include mixers, an acid feed system, pumps, and a pH
control system. The capital cost and power costs were based on
data from major manufacturers.
Labor - Annual labor expenses for both the continuous and batch
operating modes for the chemical emulsion breaking unit are shown
in Figure VIII-12 as a function 'of waste stream flow rate. For
the continuous operating mode, labor requirements are based on
estimated marihours required for diluting and mixing the polymer
and alum solutions and operating the unit. General operation
labor has been estimated at 0.75 manhours per 8 hour shift.
General maintenance of the entire system has been estimated at 2
manhours per week. :
For the batch operating mode, labor requirements are based on
estimated manhours required for diluting and mixing the polymer
and alum solutions and operating the unit. General operation
labor has been estimated at 0.75 manhours required per batch.
General maintenance of the entire system has been estimated at 1
manhour per week.
Materials - Material costs are associated with the alum and poly-
mer chemical addition requirements. Polymer is added to the
wastewater until a concentration of 150 mg/1 is attained. Alum
is added to the wastewater until a concentration of 25 mg/1 is
attained. Chemical costs have been based xipon the following unit
prices:
$0.38 per kg of alum
$1.55 per kg of polymer
The assumption has been made that the unit operates 24 hours per
day, 5 days per week, 52 weeks per year.
Ener
brea
•gy Costs - Annual energy expenses for the chemical emulsion
.king system (both batch and continuous operating modes) are
shown in Figure VIII-13 as a function of waste stream flow rate.
These costs are based on operation of the dilution tank mixers,
382
-------
chemical feed pumps, mixing and separation tank mixers (as appli-
cable), oil skimmer (as applicable), and solution transfer pumps
(oil and separation tank transfer pumps, as applicable). Energy
expenses have been estimated based upon a rate of $0.045 per
kilbwatt-hour of required electricity. It has been assumed that
the unit operates 24 hours per day, 5 days per week, 52 weeks per
year.
Chromium Reduction
Capital Cost - Chromium reduction capital costs are presented in
Figure VIII-14. Sulfuric acid is added for pH control and a 90
day supply is stored in the 25 percent aqueous form in an
above-ground, covered concrete tank, 0.305 meters (1 foot)
thick.
A single continuous chromium reduction tank is sized as an
above-ground cylindrical concrete tank with a 0.305 meter (1
foot) wall thickness, a 45 minute retention time, and an excess
capacity factor of 1.2. Sulfur dioxide is added to convert the
influent hexavalent chromium to the trivalent form.
The control system for chromium reduction consists of:
1 immersion pH probe and transmitter
1 immersion ORP probe and transmitter
1 pH and ORP monitor
2 slow process controller
1 sulfonator and associated pressure regulator
1 sulfuric acid pump
1 transfer pump for sulfur dioxide ejector
2 maintenance kits for electrodes, and miscellaneous
electrical equipment and piping
A completely manual system is provided for batch operation.
Subsidiary equipment includes:
1 sodium bisufite mixing and feed tank
1 metal stand and agitator collector
1 sodium bisulfite mixer with disconnects
1 sulfuric acid pump
1 sulfuric acid mixer with disconnects
2 immersion pH probes
1 pH monitor, and miscellaneous piping
Labor - The labor requirements are plotted in Figure VIII-15
(p.407 ). Maintenance of the batch system is assumed to be
negligible and so it is not shown.
383
-------
Chemical Addition - For the continuous system, sulfur dioxide is
added according to the following:
(Ibs S02/day) = (15.43) (flow to unit-MGD) (Cr+6 mg/i)
• i
In the batch mode, sodium bisulfite is added in place of sulfur
dioxide according to the following:
(Ibs NaHSC-3/day) - (20.06)(flow to unit-MGD)(Cr+6 mg/1)
Energy - Two horsepower is required for chemical mixing. The
mixers are assumed to operate continuously over the operation
time of the treatment system. ;
Given the above requirements, operation and maintenance costs are
calculated based on the following:
$6.00 per man + 15 percent indirect labor charge
- $380/ton of sulfur dioxide '.
- $20/ton of sodium bisulfite
$0.032/kilowatt hour of required electricity
Contract Hauling
As stated previously, information obtained from 511 plants in an
EPA Effluent Guideline Division study of the paint industry was
used to determine contract hauling costs. Costs in the paint
study ranged from $0.01 to over $0.50 per gallon. The paint
industry contract hauling costs included both hazardous and
nonhazardous wastes. While the Agency believes that the wastes
from copper forming are nonhazardous, EPA selected the value of
$0.30 per gallon used in the paint study for use in estimating
sludge and wastewater hauling costs.
i
Spray Rinsing
i
Spray rinsing costs represent the cost of flow reduction for
pickling rinse wastewaters. The flow used to determine spray
rinsing costs for a plant is equal to the average production-
normalized flow pickling rinse flow. Spray rinsing costs are
based on the cost of a holding tank with an additional 20 percent
added to cover the cost of'spray nozzles. The capital cost curve
for holding tanks is shown in Figure VIII-16. One transfer pump
was also included in calculations of capital and energy costs.
Recycle-Cooling
i
Capital Cost - Recycle-cooling costs include the cost of one
cooling tower, pumping and 1,000 feet of force main. Costs are
presented as a function of flow. Recycle and cooling costs
384
-------
represent the cost of flow reduction for annealing water and
solution heat treatment wastewaters. The flow used to calculate
recycle and cooling costs for a plant is equal to the plants
current flow for these waste streams minus the flows which would
be allocated to these streams under Option 2 (see Discharge
Flows, Section X, p.435 ). Capital costs for recycle and cooling
are presented in Figure VIII-17.
Operation and Maintenance Costs - Operation and maintenance
expenses include labor and electrical power. Labor is estimated
at 252 hours per year. Figure VIII-18 (p.410 ) shows the
electrical energy costs for operation of the pumps and fans for
the cooling tower.
Multimedia Filtration
Capital Cost - Capital and operation and maintenance costs for
multimedia filtration are shown in Figure VIII-19. The capital
and operating costs were based on data contained in the EPA
technology transfer Process Design Manual for Suspended Solids
Removal (EPA 625/1-75-003A), as well as inputs from several
manufacturers.
One filter unit with a bed depth of 4 to 6 feet with sand and
coal media was used for estimating costs. The unit is sized
based on a hydraulic loading of 81.45 liters/minute/square meter
of filter surface area (2 gpm/ft^). Investment costs include
filter tanks, internals, media operating valves and piping, a
pump, and automatic backwash controls.
Operation and Maintenance. The costs shown in Figure VIII-19 for
operation and maintenance includes contributions of materials,
electricity and labor. These curves result from correlations
made with data obtained by a major manufacturer. Energy costs
are estimated to be 3 percent of total OScM.
COST ESTIMATING METHODOLOGY
The costs of compliance with the various treatment options for
the copper forming industry were determined by calculating the
costs that would be incurred by a population of representative
plants. These individual plant costs were then added and the sum
was multiplied-by the ratio of the total number of plants in the
industry to the number of plants in the representative popula-
tion.
For direct dischargers, costs were determined for 10 representa-
tive direct discharging plants. For each plant, the current mass
discharge of pollutants was determined based on actual plant
wastewater flow rates and plant-specific raw waste data and
385
-------
wastewater treatment equipment in place at the plant. In cases
where actual raw waste data were not available, the average of
raw waste data from all plants was used.
For wastewaters currently being treated, effluent concentrations
were used that are based on the long-term treatability data for "
the type of treatment process in place as discussed in Section
VII.
i
The amount of pollutant reduction which would be required for
each plant to achieve the mass limitations based on the various
treatment options was then determined. New or additional treat-
ment systems were then designed and costed which would achieve
the required pollutant reduction for each plant. The costs for
these 10 plants were then added and the sum was multiplied by
37/10, the ratio of the total number of direct dischargers in the
copper forming category (37) to the number of plants selected for
costing (10).
i
A similar approach was taken for indirect dischargers. Six
representative indirect discharging plants were costed and the
sum of these costs was multiplied by 45/6, the ratio of the total
number of indirect dischargers in the copper forming category
(45) to the number of indirect discharging plants selected for
costing (6) .
Two of the plants which were costed have both direct discharges
and indirect discharges. These two plants ;were selected for
costing because this situation is representative of a number of
plants in the copper forming industry. Further, the waste
streams that are discharged from these plants to POTW are asso-
ciated with operations which are representative of plants which
discharge all wastewater to POTW. Consequently, the indirect
discharge treatment costs for these plants are also representa-
tive of all other indirect dischargers found in the copper
forming category. Because discharges from ;these plants would be
regulated under both BAT and PSES, separate costs were, developed
for the direct discharges and indirect discharges associated with
these plants. The costs associated with the direct discharges
from these plants were used in the determination of the total
cost of compliance with the BPT and BAT treatment options for the
copper forming category. Likewise, the costs associated with the
indirect discharges from these plants were used in the determina-
tion of the cost of compliance with the PSES treatment options.
For this reason, a total of 16 sets of costs were developed from
a representative population of 14 plants.
i
The plants which were used for costing were selected in order to
represent the characteristics of the total population of plants
in the copper forming category in terms of production, number and
386
-------
type of manufacturing operations present, and wastewater treat-
ment in place. As previously discussed in the overview of the
copper forming category presented in Section III, the copper^
forming category consists of approximately 176 plants, of which^
approximately 100 practice only one forming operation. Plants in
this group typically practice only drawing and annealing. Tll|s
group represents 60 percent of the category. The remaining 76
plants practice multiple forming operations (from two to five).
These plants typically practice any combination of hot rolling,
cold rolling, extrusion, drawing, and forging along with the
ancillary operations of solution heat treatment, alkaline cleanr
ing, annealing, and pickling. This group of plants represents 40
percent of the category.
Seven of the 12 plants which were visited and sampled as part of
the data gathering effort were also used for costing because they
are also representative of plants in the category in terms of
treatment costs. While the remaining five sampled plants provide
wastewater characterization data which were representative of the
major forming and ancillary operations found in the category,
they were not: used to determine treatment costs. The inclusion
of these plants would have skewed the sample population towards
plants with multiple forming operations. Accordingly, an addi-
tional seven plants comprised of single forming operations were
selected for costing. The 14 plants selected in this manner
represent a population comprised of 50 percent single forming
operation plants and 50 percent multiple forming operation
plants. As previously discussed, this distribution approximates
the makeup of plants in the category. The distribution of
production of the sample population (3-300 million pounds) also
approximates the range of production from plants in the copper
forming category.
COSTS FOR TREATMENT AND CONTROL OPTIONS
The components of the five control and treatment options which
were considered as the bases for BPT, BAT, PSES, NSPS, and PSNS
are presented below. The five options are discussed in greater
detail in Section X (p.433 ).
Option 1
The following treatment processes are costed for Option 1:
Lime precipitation and clarification,
Vacuum filtration,
Oil skimming,
Chromium reduction, and
Contract hauling.
387
-------
Option 2
The treatment processes included in Option 2 consist of all of
the Option 1 processes as well as reduction of annealing and
solution heat treatment contact cooling water flows through cool-
ing and reduction pickling rinse water flows through the use of
spray rinsing and recirculation.
Option 3
i
i
The treatment processes and flow reduction techniques included in
Option 3 consist of all of the Option 2 processes as well as
end-of-pipe polishing filtration (multimedia).
Option 4 • ,
The^treatment processes and flow reduction techniques included in
Option 4 consist of all of the,Option 3 processes and techniques
as well as additional flow reduction achieved through the use of
countercurrent rinsing in pickling operations. Countercurrent
rinsing was not costed for existing plants because Option 4 is
being proposed only for new sources. As discussed in Section X,
p. , the Agency believes that existing copper forming plants
do not have sufficient space to add countercurrent cascade
rinsing. The Agency believes that the cost of installing
countercurrent rinsing in a new plant would not be greater than
the cost of installing single stage or spray rinsing and in some
cases may actually be less because of decreased water use and
pumping requirements.
Option 5
The, treatment processes included in Option ;5 consist of all of
the Option 1 processes as well as multimedia filtration.
The cost estimates were based on treatment in-place and the
regulatory flows. Since the Option 1 regulatory flow is on the
whole larger than Option 2 flow and in-process controls tend to
be relatively inexpensive, the cost of Option 2 was less than
Option 1 for a number of plants. Therefore, the BPT costs were
based on the lowest cost option, either Option 1 or Option 2.
NORMAL PLANT COSTS
Normal plants costs are estimates of the treatment costs which
would be incurred by a hypothetical plant with no wastewater
treatment in-place with manufacturing operations representative
of the industry as a whole. The Agency has prepared eningeering
costs for all five options described above using a normal plant
to provide an indication of the relative costs of the options for
plants with little or no treatment in place. The amount of
388
-------
production and associated wastewater flows used in developing the
normal plant for the five treatment options are shown in Table
VIII-2.
The capital, annual operation and maintenance, and annualized
costs are shown in Table VIII-3. For plants without treatment in
place,, the cost of Option 4 is comparable to the cost for Option
2. Recalling that Option 4 is identical to Option 2 except that
Option 4 includes additional flow reduction an an end-of-pipe
polishing filter (multimedia), it can be seen that the reduction
in flow almost offsets the additional cost of the polishing
filter. The Agency did not take credit for savings in water
costs between Options 2 and 4; however, if these savings were
taken into account the difference in the costs between Option 2
and Option 4 would be minimized.
ENERGY AND NON-WATER QUALITY ASPECTS
The following are the nonwater quality environmental impacts
(including energy requirements) associated with the proposed
regulations.
A. Air Pollution
Imposition of BPT and BAT limitations and NSPS, PSES, and PSNS
will not create any substantial air pollution problems. The
technologies used as the basis for this regulation precipitate
pollutants found in wastewater which are then settled or filtered
from the discharged wastewater. These technologies do not emit
pollutants into the air.
B. Solid Waste
EPA estimates that copper forming facilities generated 39,000 kkg
of solid wastes (wet basis) in 1978 as a result of wastewater
treatment in place. These wastes were comprised of treatment
system sludges containing toxic metals, including chromium,
copper, lead, nickel, zinc, and spent lubricants.
EPA estimates that the proposed BPT will contribute an additional
13,000 kkg per year of solid wastes. Proposed BAT and PSES will
increase these wastes by approximately 11,000 kkg per year beyond
BPT levels. These sludges will necessarily contain additional^
quantities (and concentrations) of toxic metal pollutants. While
NSPS and PSNS will generate additional sludge, its quantity is
insignificant in relation to the amounts generated by BAT and
PSES.
The Agency examined the solid wastes that would be generated at
copper forming plants by the suggested treatment technologies and
believes they are not hazardous under Section 3001 of the
389
-------
Resource Conservation and Recovery Act (RCRA). This judgment is
made based on the recommended technology of lime precipitation.
By the addition of a small excess of lime during treatment, simi-
lar sludges, specifically toxic metal bearing sludges, generated
by other industries such as the iron and steel industry passed
the EP toxicity test. See 40 CFR Part 261.24 (45 FR 33084 (May
19, 1980)). Thus, the Agency believes that the copper forming
wastewater sludges will similarly not be found toxic if the
recommended technology is applied. Since the copper forming
solid wastes are not believed to be hazardous, no estimates were
made of costs for disposing of hazardous wastes in accordance
with RCRA requirements. '
.
Although it is the Agency's view that solid wastes generated as a
result of these guidelines are not expected to be classified as
hazardous under the regulations implementing Subtitle C of the
Resource Conservation and Recovery Act (RCRA), generators of
these wastes must test the waste to determine if the wastes meet
any of the characteristics of hazardous waste. See 40 CRF Part
262.11 (45 FR 12732-12733 (February 26, 1980)). The Agency may
also list these sludges as hazardous pursuant to 40 CFR Part
261.11 (45 FR at 33121 (May 19, 1980), as: amended at 45 FR 76624
(November 19, 1980)). j
If these wastes are identified as hazardous, they will come
within the scope of RCRA's "cradle to grave" hazardous waste man-
agement program, requiring regulation from the point of genera-
tion to point of final disposition. EPA's generator standards
would require generators of hazardous copper forming wastes to
meet containerization, labeling, record keeping, and reporting
requirements; if copper formers dispose of hazardous wastes off-
site, they would have to prepare a manifest which would track the
movement of the wastes from the generator's premises to a per-
mitted off-site treatment, storage, or disposal facility. See 40
CFR Part 262.20 (1981). The transporter regulations require
transporters of hazardous wastes to comply with the manifest
system to assure that the wastes are delivered to a permitted
facility. See 40 CFR Part 263.20 (1981). Finally, RCRA
regulations establish standards for hazardous waste treatment,
storage, and disposal facilities allowed to receive such wastes.
See 40 CFR Part 464 (46 FR 2802 (January 12, 1981), 47 FR 32274
(July 26, 1982)).
Even if these wastes are not identified as hazardous, they still
must be disposed of in compliance with the Subtitle D open dump-
ing standards, implementing 4004 of RCRA. See 44 FR 53438
(September 13, 1979). The Agency has calculated as part of the
costs for wastewater treatment the cost ofjhauling and disposing
of these wastes.
390
-------
Estimates of the amount of solid waste generated currently by
copper formers and the incremental amount of solid waste gener-
ated as a result of installing the proposed options were calcu-
lated using the following approach. The amount of solid waste
generated by treatment in place was estimated using the current
discharge flows for direct and indirect dischargers accounting
for treatment in place. For the purposes of estimating the
volume of sludge generated by chemical precipitation and sedimen-
tation it was assumed that the treatment system was operated
using ten percent excess lime, and that the hydroxide sludge^
resulting from sedimentation was concentrated using vacuum fil-
tration to 20 percent solids. Thus applying the percentage of
the industry with treatment in place (70 percent of direct dis-
chargers and 31 percent of indirect dischargers), the amount of
sludge currently generated was calculated. The incremental
amount of sludge generated under the proposed BPT were then
calculated by assuming that the portion of the flow not currently
treated would be treated using chemical precipitation and sedi-
mentation. The incremental amount of sludge generated under the
proposed BAT and PSES was calculated based on the assumption that
flow reduction measures selected reduce the overall plant flow by
approximately 60 percent.
C. Consumptive Water Loss
Treatment and control technologies that require extensive
recycling and reuse of water may require cooling mechanisms.
Evaporative cooling mechanisms can cause water loss and con-
tribute to water scarcity problems--a primary concern in arid and
semi-arid regions. While this regulation assumes water^reuse,
the quantity of water involved is not regionally significant. We
conclude that the consumptive water loss is insignificant and
that the pollution reduction benefits of recycle .technologies
outweight their impact on consumptive water loss.
D. Energy Requirements
EPA estimates that the achievement of proposed BAT effluent
limitations will result in a net increase in electrical energy
consumption of approximately 0.6 million kilowatt-hours per year.
To achieve the proposed BAT effluent limitations, a typical
direct discharger will increase total energy consumption by less
than 1 percent of the energy consumed for production purposes.
NSPS will not significantly add to total energy consumption. EPA
recognizes that there will be increased energy requirements for
pumping for NSPS with the addition of filtration; however, the
use of countercurrent cascade rinsing will reduce the wastewater
flow to the treatment system by approximately 30 percent. The
reduction in the overall flow will result in smaller overall
pumping requirements for the entire treatment system.
391
-------
The Agency estimates that proposed PSES will result in a net
increase in electrical energy consumption of approximately 0.5
million kilowatt-hours per year. To achieve proposed PSES, a
typical existing indirect discharger will increase energy con-
sumption by less than 2 percent of the energy consumed for pro-
duction purposes. PSNS, like NSPS, will not significantly add to
total energy consumption.
392
-------
rH
t
H
H
H
^
0)
3
So
•r-\
a
o
pi
o
fe
H
CO
O
o
.-3
2
H
PM
-------
i
£
u
w
u
K
*
CM
I
M
CU
>-(
g,
- 2
NVf"«) J.SOS
394
-------
CO
t
H
Q)
M
a
•H
(•£.
-t) A«O3 1VJ.UVD
395
-------
t
H
H
(I)
J-l
3)
•H
NVW
396
-------
H
M
H
(1)
P
3)
H
8
O
o
H
H
O
(•£. Nvr -
397
-------
s;
SJ
•rH-
XI
S
NV
j
•5--
:8:
-o-
-u.
.o.
-u.
-1
«
I
S
a
lll<
•>•
«
S
2
o
w
o
^w;
E§:
i-»-
T-T
\
$
Av
1 1
W
I
CO
w
Pi
M
VO
t
H
0)
3 O
&0 M
•H H
H
M
to
O
(UV3A/CMOOH) uoivi
398
-------
£
w
t
l-l
M
H
3)
H
CO
O
u
PM
P
CO
Q
5
o
M
H
j
M
QNV
399
-------
£
H
K
oo
t
H
H
0)
00
H
O
O
H
I
O
M
H
Nvr - suviioa)
400
-------
".'IX —f
il
I—I-
I!
I I
1 I
I '
i!
i T
e
u
x
i
S
t
M
H
IH
a)
^
3)
•H
Pn
CO
O
IS
H
PM
M
t*J
CO
rf
o
AtOD T VJLWV3
401
-------
w
t O
1-1 M
CO
00 g
•H
-------
l-l
a
M
0)
O
M
403
-------
aouBuaq.UT-BK pup
404
a)
C/3
EH
t/3
O
U
w
-------
in
o
O
li.
(U
I
•H
o
5
^
PQ
S3
o
M
CO
§
hJ
•d
O
a
o
hJ
pt,
^
CO
H
w
o
o
>H
O
w
.J
^
savmoa) SJ.SOD AOHHNH
405
-------
t
H
H
IH
Q)
H
8
o
H
PM
M
§
O
PM
O
H
O
Q
9
Pi!
0
(91. NVr-*J JLS09
406
-------
1
s
t
"^
>
*
V
^^
%
/
/
I
0
«
I
o
•— •
X
u
H
0 •
•
^r—
>»,
rF
1
1
\
\
%
S
1
t
I
1
1 1
1 f
1
^ "- —
- ^
\
'
J
T
*
' s
\
•
k
\
k
^^
\
f
o
r
4
c
hi
£
O
1NIJLNO
U
fc
V
-V
\
\
"
V
\
^
V
\>v
\ '*
\
1
L 1
XI
\
\
\
\
i
v !
\J
H
U
"" z
u.
*
z
u
o
?i
11 O
,..— ;* ',
*.
%i
5
z
')
u
s<
Sz
3 ft
.z "
c t
V -
o?
°5.
S
s
k
^
L
\
y
\
^»
or
e
u
<
u
<
SI
X_
s
«~
\
\
t
\
-
\
\
>
\
\
\
Sw
\
id
w
H
§
ffS
H
8-
i
•
H
H
<
B
i
^
r-H
(
M
H
1-1
>
0)
3
g
h4
S
S
^3
§
H
^
o
55
O
M
H
O
B
4
o
M
S
•unoH - woovi IVANNV
407
-------
Q..
5
.
.KK.
Ill
"
_ _
,00-
U
QQ
U3
-WJ-
<0
OZ
_Y
\
ID
o
>•
o
|
VO
I-H
c
H
H
H
0)
E
CO
H
CO
o
O
H
CO
la
H
Q
C^
W
SJ.SOO iN3WJLS3AK
408
-------
c
1
*
-
I
• 1 \
1
i
t •
^*
*
i
^J
^
>J
\
v
\
>
r _
V
\
\
\
s
e
e
e
"
0
•
O
^
5
i
1 E s
°- S o
^ . T
0 ^ ^
«
8 H ^
8 H 0
o ••*
u <" S
y tj ^g
s so
o 2 OO EH
k *
^ &y C jj
SH^
h. H
O
CJ
o
Jt*. Mvr-t)
409
-------
z
X
N
:£
|
8
i£
c
H
O
i
00
M
>
cu
^
I
O
O
410
-------
1
1
1
_•
!
1
—v
\ ]
\ t
\!
\
\
i
i
i
'. ,
i .
: ,
1 1 '
L „ ...
s
\
1
t
•
1
\
<
Ml
1
o
u
J
0.
u
\
\
\
1_
\
\
s
1
'' ,
] H
t
JL
l
oT
""u
'u
J
o
z
z
"'0
J.UI
..o
J
I
-H-
"1
^
i
i
•
^
0
8
9
0
m
0
••
o
»
•i
e
e
C/3
H
U
J
Z
t
H
H
H
>
-------
TABLE VIII-1
CLARIFIER CHEMICAL REQUIREMENTS
LIME REQUIREMENT1
POLLUTANT
Chromium, Total
Copper
Acidity
Iron, Dissolved
Zinc
Cadmium
Cobalt
Manganes e
Aluminum
0.000470
0.000256
0.000162
0.000438
0.000250
I 0.000146
! 0.000276
0.000296
0.000907
1) (Lime Demand Per Pollutant, Ibs/day) - ^Lime x Flow
Rate (GPH) x Pollutant Concentration (mg/1)
412
-------
M
H
CU .
rH
3
^
-vt-0
rH
0
0 X
•rl
4J rl
ft >->
i-H
00 xx
00
rtrH
CN X
ro JH
•rl rH
0
U^
00
rtrH
rH X
<» rl
13 !>.
•rl rH
m co o o
ON CO O ON
• • • •
rH CO O OO
m oo o o
O"\ CO ^5 O^
• • • •
i-H CO O 00
m co o o
ON CO O O
I-H co o in
CO
0
Ox
•H rl
4J >,
o-
;d bC
•Or«
0^5
0
o
ON
O
O
OO
0
o
00 OO
O
O
OO
I
o
rH
O
O
00
X
o
CO
o
00
00
• •
00
OO
•
00
m
m
oo
o o
o o
m CM
o
o
o
•
o
in
oo
•
m
co
m
CO
•
o
CM
O
O
O
•
O
m
CO
•
m
co
m
vo
o
O
60 CO
0
•rl CU
rl 4-1
0 W
4-1 rt
O J3
rt
H
s
rt
S
ent Lubricant
ft
CO
-~^
60
0
•rl
rH
rH
O
4J
O
.M
pent Lubricant
CO
* — ^
60
(3
•rl
i-H
rH
O
TJ
rH
O
CJ
Lubricant
4J
(3
(1)
ft
CO
"•~».
60
0
•rl
Jj
rt
rl
Q
Treatment/
ing Water
rH
4J 0
rt o
0) O
W
4J
0 0
o rt
•rl 4J
4J 0
3 o
i-H O
O
CO
s Heat Treat-
Cooling Water
OQ 4J
CU O
JH rt
pj | i
13
0 0
0 O
•rl-^.
03 4J
rl 0
rl CU
4J 3
W
W
60
0
•H
rH
O
O
CJ
4J
0
rt
4-1
13
O
0
60
13
•H SH
rH 0)
rt 4J
CU rt
0ps
<1
act Cooling
lution
4J O
0 CO
O
O JH
--. 0)
60 4J
0 rt
rH 1
rt I-H
CU iH
00
•^
ing/Bath
0
rt
CU
rH
0
CU
0
•rl
rH
rt
i-H
-------
Option 1
Option 2
Option 3
Option 4
Option 5
Table VIII-3
SUMMARY OF COPPER FORMING NORMAL PLANT COSTS
Capital Cost ($fs)
452,200
538,200
651,800
618,800
590,400
\ Annual Operation and
Maintenance Cost ($'s)
314,000
324,100
333,800
331,600
326,400
Option 1
Option 2
Option 3
Option 4
Option 5
Annualizedl
Cost ($)
413,500
442,500
477,200
467,700
456,300
•'•Using capital recovery factor of 0.22.
414
-------
SECTION IX
BEST PRACTICABLE CONTROL TECHNOLOGY
CURRENTLY AVAILABLE
This section identifies the effluent characteristics attainable
through the application of best practicable control technology
currently available (BPT), Section 301(b)(a)(A). BPT reflects
the existing performance by plants of various sizes, ages, and
manufacturing processes within the copper forming category, as
well as the established performance of the recommended BPT sys-
tems . Particular consideration is given to the treatment already
in place at plants within the data base.
The factors considered in identifying BPT include the total cost
of applying the technology in relation to the effluent reduction
benefits from such application, the age of equipment and facili-
ties involved, the manufacturing processes employed, and nonwater
quality environmental impacts (including energy requirements).
In general, the BPT level represents the average of the best
existing performances of plants of various ages, sizes, proces-
ses, or other common characteristics. Where existing performance
is uniformly inadequate, BPT may be transferred from a different
subcategory or category. Limitations based on transfer of
technology are supported by a rationale concluding that the
technology is, indeed, transferable, and a reasonable prediction
that it will be capable of achieving the prescribed effluent
limits (see Tanner1s Council of America v. Train. 540 F.2d 1188
(4th Cir. 1976).BPT focuses on end-of-pipe treatment rather
than process changes or internal controls, except where such
practices are common industry practice.
TECHNICAL APPROACH TO BPT
The Agency studied the copper forming category to identify the
manufacturing processes used and wastewaters generated during
copper forming. Information was collected from industry using
data collection portfolios, and wastewaters from specific plants
were sampled and analyzed.
Some of the factors which must be considered in establishing
effluent limitations based on BPT have already been discussed.
The age of equipment and facilities and processes employed were
taken into account in the discussion not to subcategorize and are
discussed fully in Section IV. Nonwater quality impacts and
energy requirements are considered in Section VIII.
415
-------
In making technical assessments of data, reviewing manufacturing
processes, and assessing wastewater treatment technology options,
both indirect and direct dischargers have been considered as a
single group. An examination of plants and processes did not
indicate any process differences based on the type of discharge,
whether it be direct or indirect. However, in determining the
technical basis representing the average of the best existing
performance, EPA considered only direct dischargers.
i
Wastewater produced by the deformation operations contains sig-
nificant concentrations of oil and grease, suspended solids, and
toxic metals. Surface cleaning produces a rinse water- in which
significant concentrations of oil and grease, suspended solids,
and toxic metals are found. The other surface treatment
wastewaters have similar characteristics.
j
BPT for the copper forming category is based upon common treat-
ment of combined streams. The general treatment scheme for BPT
is to apply lime and settle technology to remove metals and
solids from the combined wastewaters. Separate preliminary
treatment steps for chrome reduction, chemical emulsion breaking,
and oil skimming are utilized when required. The BPT effluent
concentrations are based on the performance of chemical precipi-
tation and sedimentation (lime and settle) when applied to a
broad range of metal-bearing wastewaters. The basis for lime and
settle performance is set forth in substantial detail in Section
VII (p.253).
For each of the 12 wastewater sources, a specific approach was
followed for the development of BPT mass limitations. To account
for production and flow variability from plant to plant, a unit
of production or production normalizing parameter (PNP) was
determined for each waste stream which could then be related to
the flow from the process to determine a production normalized
flow. Selection of the PNP for each process element is discussed
in Section V. Each process was then analyzed to determine
(1) whether or not operations included generated wastewater,
(2) specific flow rates generated, and (3) the specific produc-
tion normalized flows for each process.
Production normalized flows presented in Section V were analyzed
to determine which flow was to be used as part of the basis for
BPT mass limitations. The selected flow (referred to as a BPT
regulatory flow or BPT flow) reflects the water use controls
which are common practices within the industry. The BPT flow is
based on the average of all applicable data.
The general assumption was made that all wastewaters generated
were combined for treatment in a single or common treatment
system. A disadvantage of common treatment is that some loss in
416
-------
pollutant removal effectiveness will result where waste streams
containing specific pollutants at treatable levels are combined
with other streams in which these same pollutants are absent or
present at very low concentrations. Since treatment systems
considered under BPT are primarily for metals, oil and grease,
and suspended solids removal, and because they are found in most
waste streams in treatable quantities the Agency did not reject
control treatment. In addition, several existing plants usually
had one common treatment system in place, and a common treatment
system is reasonable in terms of cost and effectiveness. Both
treatment in place at copper forming plants and treatment,in
other categories having similar wastewaters were evaluated.
The overall effectiveness of end-of-pipe treatment for the
removal of wastewater pollutants is improved by the application
of water flow controls within the process to limit the volume of
wastewater requiring treatment. The controls or in-process tech-
nologies recommended under BPT include only those measures which
are commonly practiced within the category.
The Agency usually establishes wastewater limitations in terms of
mass rather than concentration. This approach prevents the use
of dilution as a treatment method (except for controlling pH).
For the development of effluent limitations, mass loadings were
calculated for each operation. This calculation was made on a
process-by-process basis, primarily because plants in this
category may perform one or more of the ancillary operations in
conjunction with the major forming operations present. The mass
loadings (milligrams of pollutant per kilogram of production unit
- mg/kg) were calculated by multiplying the BPT flow (1/kkg) by
the concentration achievable using the BPT treatment system
(mg/1) for each pollutant parameter to be regulated under BPT.
REGULATED POLLUTANT PARAMETERS
Pollutant parameters are selected for regulation in the copper
forming category because of their frequent presence at high
concentrations in untreated wastewaters. Total suspended solids,
oil and grease, pH, chromium, copper, lead, nickel, and zinc have
been selected for regulation.
Total suspended solids, in addition to being present at high con-
centrations in raw wastewater from copper forming operations, is
an important control parameter for metals removal in chemical
precipitation and sedimentation treatment systems. The metals
are precipitated as insoluble metal hydroxides, and effective
solids removal is required in order to ensure reduced levels of
toxic metals in the treatment system effluent. Total suspended
solids are also regulated as a conventional pollutant to be
removed from the wastewater prior to discharge.
417
-------
Oil and grease is regulated under BPT since a number of copper
forming operations (e.g., hot rolling, cold rolling, and drawing)
generate emulsified wastewater streams which may be discharged.
As seen in Section V, several waste streams have high concentra-
tions of the conventional pollutant oil and grease. Oil and
grease is found at elevated concentrations in waste streams asso-
ciated with lubrication and cooling, and alkaline cleaning, as
well as heat treatment when oil is used as the heat treating
medium. Generally the compounds measured by the analytical
procedure for determining oil and grease are removed in skimming
operations. When emulsions are used for lubrication it may be
necessary to apply chemical emulsion breaking technology prior to
oil skimming. :
The importance of pH control is documented in Section VII
(p.231 ), and its importance in metals removal technology cannot
be over emphasized. Even small excursions from the optimum pH
level can result in less than optimum functioning of the system
and inability to achieve specified results. The optimum operat-
ing level is usually found to be pH 8.7 to 9.3. To allow a
reasonable operating margin above this level and preclude the
need for final pH adjustment, the effluent pH is specified to be
within the range of 7.5 to 10 rather than!the more normal 6.0 to
9.0. i
Hexavalent chromium is found at high concentrations in waste-
waters from pickling operations using dichromate. Hexavalent
chromium is not regulated specifically since it is included in
total chromium. Only the trivalent form is removed by the lime
and settle technology. Therefore, the hexavalent form must be
chemically reduced in order to meet the limitation on total
chromium.
The toxic metals copper, lead, nickel, ancl zinc are selected for
regulation under BPT since they are present in wastewater as a
result of contact with copper and copper alloy products. As
discussed in Section III (p. 50 ), lead, nickel, and zinc are
used as alloying agents.
DISCHARGE FLOWS |
The BPT regulatory flows for the copper forming waste streams are
presented in Table IX-1. The flows are expressed as liters per
metric ton of production (1/kkg). A discussion of how each of
these flows was determined is presented below.
The flows which are used to calculate mass limitations and stand-
ards based on Option 1 technology were derived in the following
manner. EPA examined the reported discharge flows for each
operation, and then averaged the flows from plants demonstrating
water use practices consistent with the vast majority of plants.
418
-------
In some instances, flows are based on in-process control when
these controls are common industry practice.
Hot Rolling Spent Lubricant. The production normalized flow data
for hot rolling spent lubricants are presented in Table V-2.
Twenty-one plants reported information regarding wastewater
discharge flows from hot rolling. Of the 21 plants, 17 reported
discharges and the remaining four reported no discharge from this
operation. Nine of the remaining 17 reported recycle. The
regulatory flow is based on the average of nine plants which
reported recycle. Based on the magnitude of the reported dis-^
charge flow rates, the Agency believes that other plants practice
recycle or some other method of flow reduction; however, we did
not include these plants in the average because the plants did
not specifically report recycle. Of the 21 plants which sub-
mitted discharge information for hot rolling spent lubricant, 15
are presently at or below the BPT regulatory flow. The BPT flow
is 103 1/kkg.
Cold Rolling Spent Lubricant. The production normalized flow
data for cold rolling spent lubricant: are presented in Table V-3.
The BPT flow allowance of 379 1/kkg is based on the average
discharge flow rate of all 28 plants which reported cold rolling
operations.
Drawing Spent Lubricant. The production normalized flow data for
drawing spent lubricant are presented in Table V-4. Of the 80
plants which have drawing operations, 68 currently achieve zero
discharge through extensive recycling and contract hauling. The
Agency has selected zero discharge for this waste stream because
85 percent of the plants achieve zero discharge.
Solution Heat Treatment Contact Cooling Water. The production
normalized flow data for solution heat treatment are presented in
Table V-5. A review of these data revealed that the amount or,
water used and discharged does not vary significantly as a
function of which major forming operation it follows. Refer to
Table V-5 (p.89 ). The BPT flow allowance is based on the
average discharge flow rate of the 21 plants which reported a
discharge of solution heat treatment wastewater. While three
other plants reported zero discharge, the Agency believes that
plants have to discharge a portion of the recirculating flow to
prevent the buildup of dissolved solids. Therefore, these plants
were not included in the average. The resulting flow allowance
is 2,541 1/kkg.
Extrusion Press Solution Heat Treatment. The production normal-
ized flow data for extrusion press solution heat treatment are
presented in Table V-6. The BPT flow allowance of 2.00 1/kkg is
based on the average discharge flow rate of the three plants
which reported a discharge of extrusion press solution heat
treatment wastewater.
419
-------
Alkaline Cleaning Bath. The production normalized flow data for
alkaline cleaning bath wastewater are presented in Table V-7. The
BPT flow allowance of 46.7 1/kkg is based on the smaller of the
two discharge flows reported. The larger reported flow (2,790
1/kkg) was not averaged because it is believed to be incorrectly
reported. This flow was reported by a plant with a very small
production of approximately 10 tons per year of copper tubing.
This plant does not report rinsing following alkaline cleaning
and therefore is probably showing a flow for both the bath and
rinse streams.
Alkaline Cleaning Rinse. The production normalized flow data for
alkaline cleaning rinses are presented in Table V-8. Only one
plant reported recycle of alkaline cleaning rinse water. The BPT
flow allowance of 4,214 1/kkg is based on the average flow of all
five plants which reported a discharge of alkaline cleaning
rinse wastewater. The plant practicing recycle was included in
the average becasue it's flow was not significantly different
than plants without recycle.
I
Annealing Water. The production normalized flow data for anneal-
ing water are presented in Table V-9. Twenty-two of the 33
plants using annealing water reported a discharge. Eleven plants
reported^zero discharge of annealing water; however, they gener-
ally achieve zero discharge through natural evaporation or land
application. Natural evaporation and land; application is not
available to all plants. The Agency believes that a periodic
discharge from this waste is necessary to control levels of
dissolved solids. Therefore, the BPT flow allowance is based on
the average flow of all plants which reported a discharge. The
BPT flow allowance is 5,667 1/kkg. ;
Annealing Oil. The production normalized flow data for annealing
oil are presented in Table V-10. Zero discharge is typically
achieved through contract hauling of the relatively small quanti-
ties of annealing oil which are periodically dumped. There are
no direct dischargers of annealing oil. Consequently, the Agency
has selected zero discharge for this waste stream.
Pickling Bath. The production normalized flow data for pickling
baths are presented in Table V-ll. The BPT flow allowance of 116
1/kkg is based on the average flow of the 11 plants which
reported discharges from pickling baths.
i
Pickling Rinse. The production normalized flow data for pickling
rinses are presented in Table V-12. The reported values ranged
from 65.58 to 257,000 1/kkg. Two plants reported production
normalized flows approximately four times higher than any other
reported values. The BPT flow allowance of 3,622 1/kkg is based
on the median flow of all 44 plants which ireported pickling
rinses. The median was used rather than the average to lessen
the influence of the two extreme values. !
420
-------
Pickling Fume Scrubbers. The production normalized flow data for
pickling fume scrubbers are presented in Table V-13. The BPT
flow allowance of 626 1/kkg is based on the average flow from two
of the three plants which reported pickling fume scrubbers. The
third and highest value was not -included in the average because
the,Agency believes that it was incorrectly reported.
Plants discharging greater than regulatory flows for a given
stream may have to reduce their discharge rate for that process.
Alternatively, in that plants are only required to comply with a
total discharge mass based limit, plants have the option of sub-
stantially reducing their water discharges from other process
operations by any means. Information from plant visits shows
that many plants with greater than average flows water use water
based on historical considerations without regard to actual
process requirements. Consequently, the Agency believes that
plants can achieve the BPT regulatory flows without engineering
modifications and therefore should not incur significant costs.
Treatment Train
Option 1 represents the average of the best existing performance
of pollution control technology currently used by copper forming
plants. There are 36 plants that use chemical precipitation and
sedimentation. Twenty-five of these plants are direct dis-
chargers. There are ten plants that use oil skimming and eight
plants that practice hexavalent chromium reduction as preliminary
treatment prior to chemical precipitation and sedimentation.
The BPT treatment train consists of chemical precipitation and
sedimentation and preliminary treatment, where necessary, con-
sisting of chemical emulsion breaking, oil skimming, and hexa-
valent chromium reduction. The effluent from preliminary treat-
ment is combined with other wastewaters for common treatment by
oil skimming and chemical precipitation and sedimentation. The
hot rolling spent lubricant, cold rolling spent lubricant,
annealing oil, extrusion press heat treatment, alkaline cleaning
bath, and alkaline cleaning rinse waste streams may require
chemical emulsion breaking and oil skimming prior to combined
treatment. The pickling bath and rinse waste streams may require
hexavalent chromium treatment prior to combined treatment. The
pickling fume scrubber and annealing water waste streams gener-
ally will not require any preliminary treatment. This treatment
train is presented in Figure IX-1.
Effluent Limitations
The effluent concentrations resulting from the application of the
BPT technology are identical for all wastewater streams; however,
the mass limitations vary for each waste stream depending on the
421
-------
regulatory flow. The effluent concentrations which were used as
the basis for BPT mass limitations are presented in Table VII-21,
p.366 !
The treatment performance data discussed in Section VII is used
to obtain maximum daily and monthly average pollutant concentra-
tions. These concentrations (mg/1; along with the copper forming
regulatory flows (1/kkg of copper processed) are used to obtain
the maximum daily and monthly average values (mg/kg) for effluent
limitations and standards. The monthly average values are based
on the average of 10 consecutive sampling days. The 10 day
average value was selected as the minimum number of consecutive
samples which need to be averaged to arrive at a stable slope on
a statistically based curve relating one day and 30 day average
values and it approximates the most frequent monitoring require-
ment of direct discharge permits. The monthly average numbers
shown in the regulation are to be used and by permit writers in
writing direct discharge permits.
Effluent limitations representing the degree of effluent reduc-
tion attainable by the application of the best practicable
control technology currently available (BPT) are shown in Tables
IX-1 through IX-12. j
I
Compliance Costs and Environmental Benefits
j
In establishing BPT, EPA considered the cost of treatment and
control in relation to the effluent reduction benefits. BPT will
remove 27,000 kilograms of toxic pollutants (metals and organics)
and 56,000 kilograms of conventional and nonconventional pollu-
tants per year beyond current discharge levels. The estimated
capital investment cost to comply with BPT is $1.87 million (1978
dollars), with a total annual cost of $0.78 million. The Agency
estimates that 11 of the 37 direct dischargers presently comply
with BPT, and an additional 15 plants can achieve the limitations
without incurring significant costs.
.422
-------
§
S3
.H
B
1
£
a
ta
i
B
a)
a.
•H
O
423
-------
Table IX-1
BPT FOR HOT ROLLING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs)of Copper Hot Rolled
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
0.044
0.20
0.016
O.i5
0.14
2.06
4.23
0.018
Ooll
0.014
11
06
24
06
Within the range of 7.5 to 10.0
at all times
Table IX-2
BPT FOR COLD ROLLING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams; Per Off Kilogram
(Ibs/million Ibs) of Copper Cold Rolled
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
O.lj6
0.72
0.057
0.5f4
0.51
7.58
15.5^
Within the range of 7.5 to 10.0
at all times
0.065
0.38
0.050
0.38
0.22
.55
.58
4,
7,
424
-------
Table IX-3
BPT FOR DRAWING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Drawn
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table IX-4
BPT FOR SOLUTION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Quenched in
Water
Chromium .
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
1.07
4.83
0.39
3.58
3.38
50.82
104.19
0.43
2.54
0.33
2.54
1.42
30.49
50.82
Within the range of 7.5 to 10.0
at all times
425
-------
Table IX-5 ;
BPT FOR EXTRUSION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Heat |Treated on an
Extrusion Press
i
0.000|84 0.00034
0.0038 0.0020
0.00030 0.00026
0.0028 0.0020
0.0026 0.0011
0.040 0.024
0.082 0.040
Within the range of 7.5 to 10.0
at all times
Table IX-6
BPT FOR ANNEALING WITH WATER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
2.38 0.97
10.77 i 5.67
0.85 0.74
7.99 5.67
7.54 3.17
113.34 68.00
232.35 ; 113.34
Within the range of 7.5 to 10.0
at all times
426
-------
Table IX-7
BPT FOR ANNEALING WITH OIL
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in a Lubricant
Solution
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Within the range of 7.5 to 10.0
at all times
Table IX-8
BPT FOR ALKALINE CLEANING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
Cleaned
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
1.77
8.01
0.63
5.94
5.60
84.28
172.77
0.72
4.21
0.55
4.21
2.36
50.57
84.28
Within the range of 7.5 to 10.0
at all times
427
-------
Table IX-9
i
BPT FOR ALKALINE CLEANING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
Cleaned
0.020 0.0080
0.089 0.047
0.0071 0.0061
0.066 0.047
0.062 0.026
0.93 0.56
1.91 0.94
Within the range of 7.5 to 10.0
at all times
Table IX-10
BPT FOR PICKLING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
.Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
1.52, 0.62
6.88; 3.62
0.54 0.47
5.12 3.62
4.82, 2.03
72.44 43.46
148.50 72.44
Within the range of 7.5 to 10.0
at all times
428
-------
Table IX-11
BPT FOR PICKLING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
0.049 0.020
0.22 0.12
0.017 . 0.015
0.16 0.12
0.16 0.065
2.32 1.39
4.76 2.32
Within the range of 7.5 to 10.0
at all times
Table IX-12
BPT FOR PICKLING FUME SCRUBBER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
0.26
1.19
0.094
0.88
0.83
12.52
25.67
0.11
0.63
0.081
0.63
0.35
7.51
12.52
Within the range of 7.5 to 10.0
at all times
429
-------
•I" i ' f""!* '.,,,,'IH ': , p!'1,-!1!1 W1!"!'!,'! ,,:l,",,,Ji" , !''
-------
SECTION X
BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
The effluent limitations which must be achieved by July 1, 1984
are based on the best control and treatment technology employed
by a specific point source within the industrial category or sub-
category, or by another industry where it is readily transfer-
able. Emphasis is placed on additional treatment techniques
applied at the end of the treatment systems currently employed
for BPT, as well as improvements in reagent control, process con-
trol, and treatment technology optimization.
The factors considered in assessing best available technology
economically achievable (BAT) include the age of equipment and
facilities involved, the process employed, process changes, non-
water quality environmental impacts (including energy require-
ments), and the costs of application of such technology. BAT
technology represents the best existing economically achievable
performance of plants of various ages, sizes, processes, or other
characteristics. Those categories whose existing performance is
uniformly inadequate may require a transfer of BAT from a differ-
ent subcategory or category. BAT may include process changes or
internal controls, even when these are not common industry
practice. This level of technology also considers those plant
processes and control and treatment technologies which at pilot
plant and other levels have demonstrated both technological per-
formance and economic viability at a level sufficient to justify
investigation.
TECHNICAL AP3?ROACH TO BAT
In pursuing this second round of effluent regulations, the Agency
reviewed a wide range of technology options and evaluated the
available possibilities to ensure that the most effective and
beneficial technologies were used as the basis of BAT. To accom-
plish this, the Agency elected to examine technology alternatives
which could be applied to copper forming as BAT options and which
would represent substantial progress toward prevention of pollut-
ing the environment above and beyond progress achievable by BPT.
The statutory assessment of BAT considers costs, but does not
require a balancing of costs against effluent reduction benefits
[see Weyerhaeuser v. Costle, 11 ERG 2149 (D.C. Cir. 1978)];
however, in assessing the proposed BAT, the Agency has given
substantial weight to the reasonableness of costs.
431
-------
Under these guidelines, five levels of BAT were evaluated for the
category. Option 1 is BPT treatment. Option 2 is BPT treatment
plus flow reduction. Option 3 provides additional treatment by
including end-of-pipe filtration technology, and Option 4 is
Option 3 plus additional flow reduction of pickling rinsewater
through the use of countercurrent cascade rinsing. Option 5 adds
filtration as an end-of-pipe treatment process to Option 1 which
does not include flow reduction. Each treatment technology
option is based on common treatment of all waste streams and
results in the same concentrations of pollutants in the effluent
regardless of the number and combinations of copper forming waste
streams entering the treatment system. Mass limitations derived
from these options may vary because of the impact of different
regulatory flows. The derivation of these regulatory .flows is
discussed later in this section.
In summary form, the treatment technologies considered for BAT
for copper forming are:
Option 1 (Figure X-l) is based on:
Lime and settle (chemical precipitation of metals,
followed by sedimentation), and where required
Chemical emulsion breaking,
|
Oil skimming, and
Hexavalent chromium reduction.
This option is equivalent to the same technology on which BPT is
based.
Option 2 (Figure X-2) is based on:
Option 1, plus process wastewater flow reduction by the
following methods:
- Recycle of solution heat treatment contact cooling
water.
- Recycle of annealing contact cooling water.
Spray rinsing and recirculation of the pickling
rinse stream.
Option 3 (Figure X-3) is based on:
Option 2, plus polishing filtration (multimedia).
432
-------
Option 4 (Figure X-4) is based on:
Option 3, plus further reduction of flow through the
use of countercurrent cascade rinsing on the pickling
rinse stream.
Option 5 (Figure X-5) is based on:
Option 1, plus polishing filtration (multimedia).
The Agency considered but ultimately rejected thermal emulsion
breaking as a treatment component of BAT. Thermal emulsion
breaking is practiced at six copper forming plants. This process
removes water from oil emulsions allowing the water to be reused
and the oil to be reused or disposed of efficiently without dis-
charge. Thermal emulsion breaking has high energy requirements
and with the rapid escalation of energy costs over the last
decade is a high cost technology. EPA did not include thermal
emulsion breaking as part of the BAT model technology because
plants using chemical emulsion breaking in combination with oil
skimming, will achieve the same level of oil removal as plants
using thermal emulsion breaking. Most copper forming plants will
utilize chemical emulsion breaking because it will be less expen-
sive than thermal emulsion breaking; however, plants with waste
heat available may want to use thermal emulsion breaking to
achieve the BAT oil and grease limitation.
OPTION 1
Option 1 represents the BPT end-of-pipe treatment technology.
This treatment train consists of preliminary treatment, when
necessary, of chemical emulsion breaking and oil skimming, and
hexavalent chromium reduction. The effluent from preliminary
treatment is combined with other wastewaters for common treat-
ment by lime and settle.
OPTION 2
Option 2 builds upon the BPT end-of-pipe treatment technologies
of skimming, lime and settle with preliminary treatment to reduce
hexavalent chromium and chemically break emulsions. Flow reduc-
tion measures, based on in-process changes, are the mechanisms
for reducing pollutant discharges at Option 2. The flow reduc-
tion measures concentrate the pollutants present in these waste
streams. Treatment of a more concentrated stream allows a
greater net removal of pollutants and economies of treating a
reduced flow. The methods for reducing process wastewater
generation include recycle of solution heat treatment contact
cooling water and annealing contact cooling water through cooling
towers and recirculation. Spray rinsing and recirculation of the
433
-------
rinsewater is the method for reducing wastewater discharges from
the pickling rinse waste stream. These in-plant control measures
were discussed in detail in Section VII (p.297 ).
OPTION 3 , ;
Option 3 builds upon the technical basis of•Option 2 by adding
conventional multimedia filtration after the Option 2 treatment
train and the in-process flow reduction controls.
OPTION 4 ' : !"
Option 4 builds upon the technologies established for Option 3 by
adding another in-process flow reduction control, countercurrent
cascade rinsing for the pickling rinse waste stream.
OPTION 5 !
Option 5 builds upon the technical basis of Option 1 by adding
conventional multimedia filtration after the Option 1 treatment
train. Gravity, mixed-media filtration wasiused as the technical
basis for establishing treatment performance of filtration in
Section VII (p.237 ). EPA believes that other filtration tech-
nology such as pressure filtration is equally applicable.
BAT OPTION SELECTION !
i
For BAT, EPA is proposing limitations based on Option 2. The
Agency selected Option 2 because it results in substantial reduc-
tion of toxic pollutants above the removal achievable by BPT.
This technology option is comprised of Option 1 (BPT) plus flow
reduction. Flow reduction consists of recycle of the annealing
water and solution heat treatment streams, and spray rinsing and
recirculation of pickling rinse water. This technology consists
of end-of-pipe treatment equivalent to Option 1 which is chemical
precipitation and sedimentation and where required chemical emul-
sion breaking, oil skimming, and hexavalent chromium reduction.
All wastes are treated centrally. The treatment achieves the
concentrations discussed in Section VII (p.366). The improved
incremental pollutant removal brought about by Option 2 results
from in-process flow reduction. The discharge flows arid the
rationale for the selection of these flows are presented in a
later subsection, entitled Discharge Flows (p.435).
Although EPA is proposing effluent limitations based on technol-
ogy Option 2, the Agency will give equivalent consideration to
promulgating limitations based on technology Option 3. Section
VII (p.262 ) contains a discussion of the treatment effectiveness
that can be achieved using Option 3 and Section II contains
effluent limitations tables based on Option 3 technology in the
434
-------
subsection entitled Alternate Limitations and Standards (p.31 ).
Options 4 and 5 were considered for BAT, but were ultimately
rejected for the reasons discussed below.
Option 4. is based on the installation of countercurrent cascade
rinsing for rinse water associated with pickling. This technol-
ogy option was rejected for BAT because it is only demonstrated
at four copper forming plants and because most of the other
existing plants lack sufficient space to add the additional rinse
tank and associated piping required for countercurrent rinsing.
Option 5 is based on filtration added to Option 1. Option 5 was
considered and ultimately rejected because as compared to Option
2 it provides only one-fourth as much pollutant removal at
approximately the same costs.
REGULATED POLLUTANT PARAMETERS
In implementing the terms of the Settlement Agreement in NRDC v.
Train, Op. Git., and 33 U.S.C. § 1314(b)(2)(A and B)(197677~the
Agency placed particular emphasis on the toxic pollutants. The
raw wastewater concentrations from the individual operations and
the category as a whole were examined to select those pollutant
parameters found at frequencies and concentrations warranting
regulation. The regulated pollutants are chromium, copper, lead,
nickel and zinc. The toxic organics selected for regulation in
Section VI are not specifically regulated at BAT because the oil
and grease limitation proposed at BPT should provide adequate
removal. Refer to Section VII (p. 247 ) for an expanded discus-
sion of the removal effectiveness of the toxic organics with the
application of oil skimming. (See Table VII-12and Figure VII-9 ,
p.357 and316).
DISCHARGE FLOWS
EPA studied each of the waste streams to assess the potential of
flow reduction at BAT by using the information provided in the
dcp and by observing examples of flow reduction during the sam-
pling trips. The most commonly observed flow reduction tech-
niques were recycle of solution heat treatment contact cooling
water and annealing contact cooling water through cooling towers
prior to recirculation. Spray rinsing of recirculated rinse
water and countercurrent cascade rinsing were also observed.
Spray rinsing is practiced on pickling lines in 16 plants and
likewise four plants use countercurrent rinsing. Countercurrent
cascade rinsing was not included for BAT for reasons presented
under BAT Option Selection. Information available regarding
discharge flows from other waste streams did not support reduc-
tion beyond BPT. Therefore, for these waste streams the BAT
regulatory flow allowances are equal to the BPT flow allowances
for all of the copper waste streams except solution heat
435
-------
treatment, annealing water and pickling rinse. The BAT flow
allowances for these three streams are presented in Table X-l. A
discussion of how each of these three flows was determined
follows. !
Solution Heat Treatment. The production normalized flow data for
solution heat treatment are presented in Table V-5. Recycle is
practiced by eight of the 24 plants which reported solution heat
treatment. The reported recycle rates range from 85 percent to
100 percent. The plants currently recycling this water .are using
cooling towers to remove excess heat. Although three plants
reported no discharge of wastewater from solution heat treatment,
the Agency believes that most plants may have to discharge a
portion of the recirculating flow to prevent the buildup of
dissolved solids. Consequently, these three plants were not used
to obtain average. The Agency based the BAT regulatory flow
allowance of 646 1/kkg on the average flow reported by the five
plants which not only practice recycle but also reported
discharge flow rates. ;
Annealing Water. The production normalized flow data for anneal-
ing water are presented in Table V-9. Eleven plants reported
zero discharge of annealing water. The Agency did not select
zero discharge for BAT because they generally achieve zero dis-
charge through natural evaporation or land application. Six of
the 22 plants which discharge annealing water practice recycle.
The reported recycle rates for these six plants range from 50
percent to 98 percent. Plants recycling this water do so in the
same manner as plants recycling solution heat treatment water.
As such, EPA based the regulatory flow allowance of 1,2,40 1/kkg
on the average flow reported by the six discharging plants which
practice recycle.
Pickling Rinse. The production normalized flow data for pickling
rinses are presented in Table V-12. Sixteen of the 42 plants
reporting pickling rinse water use spray rinsing. Five other
plants did not indicate in the dcp that spray rinsing was used,
but based on the reported discharge flow rates the Agency
believes that these plants are using spray rinsing or an equiva-
lent flow reduction technique to attain these flows. EPA based
the BAT regulatory flow on the average of the twenty-one plants
which represent the lower 50'th percentile of the reported pro-
duction normalized flows. The BAT flow is 1,306 1/kkg.
Treatment Train
EPA has selected Option 2 as the basis for BAT in this category.
Again, this option uses the same technology as BPT, with the
addition of measures to reduce the flows from selected waste
streams. The end-of-pipe treatment configuration is shown in
436
-------
Figure X-2. The combination of in-process control and technology
significantly increases the removals of pollutants over that
achieved by BPT and at a reasonable cost.
Effluent Limitations
Table VII-21 (p.366 ) presents the treatment effectiveness corre-
sponding to the BAT treatment train for the pollutants selected.
Effluent concentrations (one day maximum and ten day average
values) are multiplied by the normalized discharge flows sum-
marized in Table X-l to calculate the mass of pollutants allowed
to be discharged per mass of product. The results of these
calculations are shown in Table X-2 through X-13.
Benefits
In establishing BAT, EPA considered the cost of treatment and
control in relation to the effluent reduction benefits. The
application of the proposed BAT will remove 31,000 kilograms per
year of toxic pollutants (metals and organics) from current dis-
charge levels. The estimated capital investment cost is $4--77
million (1978 dollars) and a total annual cost of $1.54 million
for equipment and in-process changes not presently in place.
The incremental effluent reduction benefits of BAT above BPT are
the removal annually of 4,000 kg of toxic pollutants. The incre-
mental costs of these benefits are $2.92 million capital cost and
$0.8 million total annual costs.
As stated above, EPA is considering promulgating limitations
based on technology Option 3. Option 3 consists of Option 2 plus
filtration. The addition of the filter results in an additional
removal of 5,000 kg/yr of toxic pollutants above BPT. The Agency
estimates that this will result in $5.31 million (1978 dollars)
in capital expenditures and $1.46 million on an annual basis.
437
-------
B
H
fn
I
8
CO
60
•S
8
H
1
cd
0)
M
H
g
•H
u a a
S3 B
5U u §
111-
S
EK
|
o
•H
Su
01 u
o. e
CO CO
60 5
C H
O .
C
U
§
*
g
a
i
u
£
u
CO
1
s
3
Solution Heat Treal
Extrusion Press Heal
Alkaline Cleaning 1
Alkaline Cleaning 1
438
-------
I
-
§
ed
Q)
H
EH
CM
g
•r-l
s
QJ 4
Cu
o
oo
I
439
-------
I
rt
I? S
•H
PU
O
to
C
•H 1)
r-l CO
A! B
U -H
•H OS
s.
CO
a. c
co a
o
60 T(
5JS
**
I
§:
ex «
co o
a d -ss i g
rK O O 13 T* T*
DC
I
O ?S 1-4
•W -H
440
-------
i
CO
e
i
o
cd
g
6
4-1
cd
0)
§
•H
4->
OH
O
•§ •§ S
s s s
V 4-1 CO
§B to
01 til
e. o, u
O3 W Oi 4J
M Sf e o
60 60
5 5
01 01
e a
60
e>o . 60 e
5* .Soi-S
33 ss-|
b Pu X
2
o.
en
•H M
t-l 111
CO 4J
s^
- a-
£ S
^S e g
O M
-------
,-i ^
s|
u e i
ea S
c o a
O -H S
T< U U u
w .o e fi
J> 3 S **
3rJ K u
u a
e> a. H
a. tn
s
•a
§
M
cd
5-4
H
-U
e
a)
tn
4J
••8
G.
•rt
O
I
»H H C
r+ O O
O K -r<
0)
5
442
-------
Table X-l
BAT REGULATORY FLOWS FOR COPPER FORMING WASTE STREAMS
REQUIRING FLOW REDUCTION
Waste Stream
Solution Heat Treatment
Annealing Water
Pickling Rinse
BAT Flow (1/kkg)
646
1,240
1,306
443
-------
Table X-2
BAT FOR HOT ROLLING SPENT
,UBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Hot Rolled
Chromium
Copper
Lead
Nickel
Zinc
0.044
0.20
0.016
0.15
0.14
0.018
0.11
0.014
0.11
0.058
Table X-3
BAT FOR COLD ROLLING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average^
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Cold Rolled
Chromium
Copper
Lead
Nickel
Zinc
444
0.16
0.72
0.057
0.54
0.51
0.065
0.38
0.050
0.38
0.22
'<«!
-------
Table X-4
BAT FOR DRAWING SPENT LUBRICANT
Pollutant
or Pollutant
Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Drawn
Chromium
Copper
Lead
Nickel
Zinc
0
0
0
0
0
0
0
0
0
0
Table X-5
BAT FOR SOLUTION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Quenched in Water
Chromium
Copper
Lead
Nickel
Zinc
0.27
1.23
0.097
0.91
0.86
0.11
0.65
0.084
0.65
0.36
445
-------
Table X-6 ;
BAT FOR EXTRUSION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Extrudeil and Quenched in a
Lubricant Solution
Chromium
Copper
Lead
Nickel
Zinc
0.00084
0.0038
O.Q0030
0.0028
0.0026
0.00034
0.0020
0.00026
0.0020
0.0012
Table X-7 ;
I
I
BAT FOR ANNEALING WITH WATER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Annealed and Quenched in Water
Chromium
Copper
Lead
Nickel
Zinc
0.52
2.36
0.19
1.75
1.65
0.21
1.24
0.16
1.24
0.69
446
-------
Table X-8
BAT FOR ANNEALING WITH OIL
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Annealed and Quenched in a
Lubricant Solution
0
0
0
0
0
0
0
0
0
0
Table X-9
BAT FOR ALKALINE CLEANING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Alkaline Cleaned
Chromium
Copper
Lead
Nickel
Zinc
1.77
8.01
0.63
5.94
5.60
0.72
4.21
0.55
4.21
2.36
447
-------
Table X-10
BAT FOR ALKALINE CLEANING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Alkaline Cleaned
0.020
0.089
0.0071
0.066
0.062
Table X-ll
BAT FOR PICKLING RINSE
0.0080
0.047
0.0061
0.047
0.026
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
0.55
2.48
0.20
1.84
1.74
0.22
1.31
0.17
1.31
0.73
448
-------
Table X-12
BAT FOR PICKLING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
0.049
0.22
0.017
0.16
0.15
0.020
0.12
0.015
0.12
0.06
Table X-13
BAT FOR PICKLING FUME SCRUBBER
Pollutant or Pollutant Property
Maximum
For Any
One Da.y
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
0.26
1.19
0.094
0.88
0.83
0.11
0.63
0.082
0.63
0.35
449
-------
-------
SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
The basis for new source performance standards (NSPS) under
Section 306 of the Clean Water Act is the best available demon-
strated technology (BDT). New plants have the opportunity to
design the best and most efficient production processes and
wastewater treatment technologies. Therefore, BDT includes pro-
cess changes, in-plant controls (including elimination of^waste-
water streams), operating procedure changes, and end-of-pipe
treatment technologies to reduce pollution to the maximum extent
possible. This section describes the control technology for^
treatment of wastewater from new sources and presents mass dis-
charge limitations of regulated pollutants for NSPS, based on the
described control technology.
TECHNICAL APPROACH TO NSPS
All wastewater reduction and process changes applicable to a new
source have been considered previously for the BAT options. For
this reason, five options were considered for NSPS, all identical
to BAT options in Section X. The five options are summarized
below and presented in greater detail in Section X.
In summary form, the treatment technologies considered for new
copper forming facilities are:
Option 1 is based on:
Lime and settle (chemical precipitation of metals
followed by sedimentation), and where required,
Hexavalent chromium reduction,
Chemical emulsion breaking, and
Oil skimming.
Option 2 is based on:
Option 1, plus process wastewater flow minimization by
the following methods:
- Recycle of solution heat treatment contact cooling
water.
- Recycle of annealing contact cooling water.
Spray rinsing and recirculation of pickling rinse-
water.
451
-------
Option 3 is based on:
j
Option 2, plus polishing filtratzon (multimedia) at the
end of the Option 2 treatment train.
Option 4 is based on:
Option 3, plus countercurrent cascade rinsing applied
to the pickling rinse stream. '
i
Option 5 is based on:
Option 1, plus polishing filtration (multimedia) at the
end of the Option 1 treatment train.
i
A more detailed discussion of these options and their applica-
bility is presented in Section X.
NSPS OPTION SELECTION
i
i
EPA is proposing that the best available demonstrated technology
for the copper forming category be equivalent to BAT technology
with the addition of countercurrent cascade rinsing for pickling
rinsewater and the addition of filtration prior to discharge
(Option 4). The Agency recognizes that new sources have the
opportunity to implement more advanced levels of treatment
without incurring the costs of retrofit equipment, the costs of
partial or complete shutdown to install new equipment and the
costs to start up and stablize the treatment system as existing
systems would have to do.
Six copper forming plants use filtration technology as end-of-
pipe treatment prior to discharge or recycle of process water
into the plant. Four plants use countercurrent cascade rinsing
on pickling rinse lines. A technical description of these
control and treatment options is provided in Section VII on
p.227 . Countercurrent cascade rinsing and filtration are
appropriate technologies for NSPS because they are demonstrated
in this category and because new plants have the opportunity to
design and implement the most efficient prpcesses without
retrofit costs and space availability limitations. In addition,
the Agency does not believe that standards for new sources based
on Option 4 will create a barrier to entry:
REGULATED POLLUTANT PARAMETERS
i
The Agency has no reason to believe that the pollutants that will
be found in significant quantities in processes within new
sources will be any different than with existing sources. Conse-
quently, pollutants selected for regulation, in accordance with
452
-------
the rationale of Section VI, are the same ones for each subcate-
gory that were selected for BAT plus TSS, oil and grease, and pH.
DISCHARGE FLOWS
\
The discharge flows for NSPS afe identical to those for BAT for
all waste streams except pickling rinse. As was the case for
BAT, the Agency reviewed the water use and discharge practices of
copper forming plants with regard to each of the waste streams
(Tables V-2 through V-13, p. 84-99). EPA determined that addi-
tional flow reduction beyond that developed for BAT was not
demonstated except for pickling rinse water. As discussed in
Section VII, countercurrent cascade rinsing substantially
improves the efficiencies of water use for rinsing. For example,
the use of a two-stage countercurrent rinse can reduce water
usage to approximately one-tenth of that needed for a single-
stage rinse and achieve the same level of product cleanliness
(refer to example in Section VII, p. 302). Similarly, a three-
stage countercurrent rinse would reduce water usage to approxi-
mately one-thirtieth. Countercurrent cascade rinsing is
practiced at four copper forming plants.
The NSPS flow for pickling rinse water is based on the lowest
production normalized flow observed at a copper forming plant
which uses countercurrent cascade rinsing for pickling rinse.
The NSPS discharge flow is 585 1/kkg.
COSTS AND ENVIRONMENTAL BENEFITS
NSPS based on Option 4 will result in the reduction of approxi-
mately 2,000 kg/yr of toxic pollutants beyond the option proposed
for BAT. The Agency has estimated the per plant cost associated
with NSPS will be approximately equal to those for BAT. BAT is
based on technology Option 2 consisting of flow reduction, lime
and settle, and, where necessary, preliminary treatment with
chromium reduction, chemical emulsion breaking, and oil skimming.
NSPS is based on Option 4 which is Option 2 plus filtration and
greater flow reduction achieved by countercurrent cascade rinsing
of the pickling rinse stream. The data relied upon for selection
of NSPS were primarily the data developed for existing sources
which included costs on a piant-by-piant basis. The Agency
believes that the additional costs of filtration for NSPS will be
offset by the lower treatment costs associated with smaller
wastewater flows using countercurrent rinsing. (See Normal Plant
Cost, Section VIII, p.388 ) Therefore, new sources regardless of
whether they are plants with major modifications or greenfieId
sites, will have costs approximately equivalent to the costs
existings sources will incur in achieving BAT and PSES.
453
-------
EFFLUENT STANDARDS
Table VII-21 (p.366 ) presents the treatment effectiveness corre-
sponding to the NSPS treatment train for the pollutants selected.
Effluent concentrations (one day maximum and ten day average
values) are multiplied by the normalized discharge flows sum-
marized in Table VII-21 to calculate the mass of pollutants
allowed to be discharged per mass of product. The results of
these calculations are shown in Tables XI-1 through XI-12.
454
-------
Table XI-1
NSPS FOR HOT ROLLING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Hot
Rolled
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
0.038
0.13
0.011
0.057
0.11
1.03
1.55
Within the range of 7.5 to 10.0
at all times
0.016
0.063
0.0093
0.038
0.043
.03
.13
1
1
Table XI-2
NSPS FOR COLD ROLLING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Cold Rolled
0.14 0.057
0.49 0.23
0.038 0.034
0.21 0.14
0.39 0.16
3.79 3.79
5.69 5.07
Within the range of 7.5 to 10.0
at all times
455
-------
Table XI-3
NSPS FOR DRAWING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximupi
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Drawn
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
PH
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Within the range of 7.5 to 10.0
at all times
Table XI-4
NSPS FOR SOLUTION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
PH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Quenched in Water
i
0.24 0.097
0.83 0.39
0.065 0.058
0.36 0.24
0.66 0.27
6.46 6.46
9.69 7.11
Within the range of 7.5 to 10.0
at all times
456
-------
Table XI-5
NSPS FOR EXTRUSION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Extruded
and Quenched in Oil
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
0.00074
0.0026
0.00020
0.0011
0.0021
0.020
0.030
0.00030
0.0012
0.00018
0.00074
0.00084
0.020
0.022
Within the range of 7.5 to 10.0
at all times
Table XI-6
NSPS FOR ANNEALING WITH WATER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in Water
0.46 0.19
1.59 0.76
0.13 0.12
0.68 0.46
1.27 0.52
12.40 12.40
18.60 13.64
Within the range of 7.5 to 10.0
at all times
457
-------
Table XI-7 j
i
NSPS FOR ANNEALING WITH OIL
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in a Lubricant
Solution
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
PH
0
0
0
0
0
0
0
Within the range of 7.5 to 10.0
at ;all times
0
0
0
0
0
0
0
Table XI-8
i
NSPS FOR ALKALINE CLEANING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
] Cleaned
i
I
1.56 0.63
5.39 2.57
0.42 0.38
2.32 1.56
4.30 1.77
42.14 42.14
63.21 46.35
Within the range of 7.5 to 10.0
at all times
458
-------
Table XI-9
NSPS FOR ALKALINE CLEANING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
PH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
Cleaned
0.017 0.0070
0.060 0.029
0.0047 0.0042
0.026 0.017
0.048 0.020
0.47 0.47
0.70 0.51
Within the range of 7.5 to 10.0
at all times
Table XI-10
NSPS FOR PICKLING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
0.22 0.088
0.75 0.36
0.059 0.053
0.32 0.22
0.60 0.25
5.85 5.85
8.78 6.44
Within the range of 7.5 to 10.0
at all times
459
-------
Table XI-11
NSPS FOR PICKLING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
PH
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
0.043 0.018
0.15: 0.071
0.012 0.011
0.065 0.043
0.12 0.048
1.16 1.16
1.74 1.28
Within the irange of 7.5 to 10.0
at all times
Table XI-12
NSPS FOR PICKLING FUME SCRUBBER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs /million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
Oil and Grease
TSS
pH
0.23^
0.81
0.063
0.35
0.64
6.26
9.39
0.094
0.38
0.057
0.23
0.26
6.26
.89
Within the range of 7.5 to 10.0
at all times
460
-------
SECTION XII
PRETREATMENT STANDARDS
Section 307(b) of the Clean Water Act requires EPA to promulgate
pretreatment standards for existing sources (PSES), which must be
achieved within three years of promulgation. PSES are designed
to prevent the discharge of pollutants which pass through, inter-
fere with, or are otherwise incompatible with the operation of
publicly owned treatment works (POTW). The Clean Water Act of
1977 adds a new dimension by requiring pretreatment for pollu-
tants, such as heavy metals, that limit POTW sludge management
alternatives, including the beneficial use of sludges on agricul-
tural lands. The legislative history of the 1977 Act indicates
that pretreatment standards are to be technology based, analogous
to the best available technology for removal of toxic pollutants.
Section 307(c) of the Act requires EPA to promulgate pretreatment
standards for new sources (PSNS) at the same time that it promul-
gates NSPS. New indirect discharge facilities, like new direct
discharge facilities, have the opportunity to incorporate the
best available demonstrated technologies, including process
changes, in-plant controls, and end-of-pipe treatment technol-
ogies, and to use plant site selection to ensure adequate treat-
ment system installation. *
General Pretreatment Regulations for Existing and New Sources of
Pollution were published in the Federal Register, Vol'. 43, No.
123, Monday, June 26, 1978. These regulations describe the
Agency's overall policy for establishing and enforcing pretreat-
ment standards for new and existing users of a POTW and deline-
ate the responsibilities and deadlines applicable to each part in
this effort. In addition, 40 CFR Part 403, Section 403.5(b),
outlines prohibited discharges which apply--to all users of a
POTW. I
This section describes the treatment and control technology for
pretreatment of process wastewaters from existing sources and new
sources, and presents mass discharge limitations of regulated
pollutants for existing and new sources, based on the described
control technology.
DISCHARGE OF COPPER FORMING WASTEWATERS TO A POTW
There are approximately 45 plants in the copper forming industry
which discharge to a POTW. The plants that may be affected by
pretreatment standards represent about 26 percent of all of the
copper forming plants.
461
-------
Pretreatment standards are established to ensure removal of pol-
lutants which interfere with, pass through, or are otherwise
incompatible with a POTW. A determination of which pollutants
may pass through or be incompatible with POTW operations, and
thus be subject to pretreatment standards, depends on the level
of treatment employed by the POTW. In general, more pollutants
will pass through or interfere with a POTW employing primary
treatment (usually physical separation by settling) than one
which has installed secondary treatment (settling plus biological
treatment). ;
i
Many of the pollutants contained in copper forming wastewater are
not biodegradable and are, therefore, ineffectively treated by
such systems. Furthermore, these wastes have been known to pass
through or interfere with the normal operations of these systems.
Problems associated with the discharge of pollutant parameters
identified in copper forming process wastewaters to POTW were
discussed in Section VI. The discussion covered pass-through,
interference and sludge usability.
i
The Agency based the selection of pretreatment standards for the
copper forming category on the minimization of pass through of
toxic pollutants at POTW. For each subcategory, the Agency com-
pared the removal rates for each toxic pollutant limited by the
pretreatment options to the removal rate for that pollutant at
well operated^POTW. The POTW removal rates were determined
through a study conducted by the Agency at over 40 POTW and a
statistical analysis of the data. (See Fate of Priority Pollu-
tants in Publicly Owned Treatment Works. EPA 440/1-80-301,
October 1980; and Determining National Removal Credits for
Selected Pollutants for Publicly Owned Treatment Works., EPA
440/82-008, September 1982.)
The average percentage of the toxic metals removed by a
well-operated POTW meeting secondary treatment requirements is
about 50 percent (varying from 20 to 70 percent), whereas the
percentage that can be removed by a copper forming direct
discharger applying the best available technology economically
achievable is more than 90 percent.
In addition to pass through of toxic metalsj available informa-
tion shows that many of the toxic organics from copper forming
facilities may also pass through a POTW. As previously
mentioned, toxic organics are not specifically regulated at BAT
because, for direct dischargers, the BPT oil and grease limit
will adequately control toxic organics. As demonstrated by the
data presented in Section VII, Table VII-9, and Table XII-1
direct dischargers who comply with the BPT limitation for oil and
grease will remove a greater percentage of the toxic organics
than a well operated POTW achieving secondary treatment.
462
-------
The pretreatment options selected provide for significantly more
removal of toxic pollutants than would occur if copper forming
wastewaters were discharged untreated to a POTW. Thus, pretreat-
ment standards will control the discharge of toxic pollutants to
POTW and prevent pass-through.
Mass-based limitations, which are the only method used for desig-
nating pretreatment standards, are set forth below. Regulation
on the basis of concentration only is not appropriate because it
will not adequately control the amount of toxic pollutants
released, since a plant can achieve a concentration-based stand-
ard by dilution of its wastewater without actually removing any
pollutant mass. Therefore, the Agency is not proposing concen-
tration-based pretreatment standards (40 CFR Part 403.6).
TECHNICAL APPROACH TO PRETREATMENT
Under these standards, five levels of PSES and PSNS were evalu-
ated for the category. Option 1 is BPT treatment. Option 2 is
BPT treatment, plus flow reduction. Option 3 includes a filter in
addition to Option 2 treatment technology. Option 4 includes all
of the elements of Option 3 plus further reduction of the
pickling rinse flow through countercurrent cascade rinsing.
Option 5 adds filtration as an end-of-pipe treatment process to
Option 1. Each treatment technology option is based on central
treatment of all waste streams and results in the same concentra-
tions of pollutants in the effluent regardless of the number and
combinations of copper forming waste streams entering the treat-
ment system. Mass limitations derived from these options may
vary because of the impact of different regulatory flows. The
derivation of these regulatory flows is discussed later in this
section.
In summary form, the treatment technologies considered for PSES
and PSNS for copper forming are:
Option 1 is based on:
Lime and settle (chemical precipitation of metals,
followed by sedimentation), and where required
Chemical emulsion breaking,
Oil skimming, and
Hexavalent chromium reduction.
This option is equivalent to the same technology on which BPT is
based.
463
-------
Option 2 is based on:
Option 1, plus process wastewater flow reduction by the
following methods:
Recycle of solution heat treatment contact cooling
water.
Recycle of annealing contact cooling water.
i
Spray rinsing and recirculation of rinse pickling
rinse water.
[,' LiLi,,!,,,11,',!.' ii'isi! ifi, :, ,,;r» .,.1 • ,,,'i,,ni , k' , IL ",,,i,,!!,i, "i • ,„"!•:
Option 3 is based on: !
Polishing filtration (multimedia) at the end of the
Option 2 treatment train.
Option 4 is based on:
Option 3, plus further reduction of the pickling
rinse flow through the use of countercurrent cascade
rinsing.
I
Option 5 is based on:
Option 1, plus polishing filtration (multimedia) at the
end of the Option 1 treatment train.
PSES OPTION SELECTION
EPA is proposing PSES based on the application of technology
Option 2. Option 2, which is also the basis for BAT limitations,
consists of chemical precipitation and sedimentation, flow reduc-
tion, ^ and preliminary treatment, where necessary, consisting of
chromium reduction, chemical emulsion breaking, and oil skimming.
The Agency believes that there may be pass through of toxic
organic pollutants from plants in this category. Given the mix
of toxic organic pollutants found in these waste streams and the
fact that they may pass through POTW, we propose to establish a
pretreatment standard for total toxic organics (TTO) to control
these pollutants. The proposed TTO standard is based on the
application of oil and grease removal technology which achieves
the same removal of TTO as the BPT model treatment technology.
Oil and grease removal is a relatively inexpensive technology
which may be used to control toxic organics when compared with
treatment technologies such as biological treatment or activated
carbon. In addition, oil and grease removal may be an important
part of good treatment for metals removal.
,., T 1iii,ii:;ilP\illF I 'ii'll1'.',!,,'1!1*
464
-------
EPA proposes to establish a Total Toxic Organics (TTO) limitation
based on the data presented in Section VII of this document. The
list of organics included under TTO is presented in Table XII-1.
Analysis of toxic organics is costly and requires delicate and
sensitive equipment. Therefore, 'the agency proposes to establish
as an alternative to monitoring for total toxic organics, an oil
and grease limit equivalent to the BPT limit for which the
analysis is much less costly and frequently can be done at the
plant. Data available to EPA indicates that the toxic organics
are in the oil and grease and by removing the oil and grease the
toxic organics should also be removed. See Table VII-9.
The PSES set forth in the proposed regulation are expressed in
terms of mass per unit of production rather than concentration
standards. Regulation on the basis of concentration only is not
appropriate because concentration based standards do not restrict
the total quantity of pollutants discharged. Flow reduction is a
significant part of the model technology for pretreatment because
it results in more concentrated waste streams which further
result in more effect pollutant removal.
Although EPA is proposing PSES based on technology Option 2, the
Agency will give equivalent consideration to promulgating limi-
tations based on technology Option 3. Section VII (p.262 )
contains a discussion of the treatment effectiveness that can be
achieved using Option 3 and Section II contains effluent limi-
tations tables based on Option 3 technology in the subsection
entitled Alternative Limitations and Standards (p.31). Options 4
and 5 were considered for BAT, but were ultimately rejected for
the reasons discussed below.
Option 4 is based on the installation of countercurrent cascade
rinsing for rinse water associated with pickling. This technol-
ogy option was rejected for BAT because it is only demonstrated
at four copper forming plants and because most of the other
existing plants lack sufficient space to add the additional rinse
tank and associated piping required for countercurrent rinsing.
Option 5 is based on filtration added to Option 1. Option 5 was
considered and ultimately rejected because as compared to Option
2 it provides only one-fourth as much pollutant removal at
approximately the same costs.
PSNS OPTION SELECTION
The technology basis for PSNS is Option 4 which is equivalent to
NSPS. The Agency has determined that PSNS based on Option 4 is
necessary to prevent pass through of toxic metals and organics.
In selecting the technology basis for PSNS, the Agency compares
the toxic pollutant removal achieved by a well-operated POTW to
465
-------
that achieved by a direct discharger meeting NSPS. New indirect
dischargers, like new direct dischargers, have the opportunity to
design and implement the most efficient processes without retro-
fit costs and space availability limitations.
COSTS AND ENVIRONMENTAL BENEFITS OF PSES AND PSNS
The application of PSES will remove 18,700 kilograms per year of
toxic pollutants (metals and organics) beyond current discharge
levels. EPA estimates that the capital investment costs of com-
plying with PSES is $6.15 million (1978 dolilars) with a total
annual cost of $4.08 million.
PSNS will result in the additional removal of 1,500 kg/yr beyond
that achieved by PSES. The Agency believes that the additional
costs of filtration for PSNS will be offset by the lower treat-
ment costs associated with smaller wastewater flows using
countercurrent rinsing. Therefore, new sources regardless of
whether they are plants with major modifications or greenfield
sites, will have costs approximately equivalent to the costs
existing sources will incur in achieving BAT and PSES.
REGULATED POLLUTANT PARAMETERS
Twelve toxic organics have been selected since they may pass
through a POTW as discussed above. They are listed in Table
XII-1. As discussed above, oil and grease is being proposed as
an alternate monitoring parameter for both PSES and PSNS, since
removal of oil and grease through the application of oil skimming
effectively removes these 12 toxic organics. The toxic metals
selected are copper, chromium (total), lead, nickel, and zinc.
TSS is not regulated since it is adequately handled by a POTW and
will not interfere with its operation.
EFFLUENT STANDARDS [
Table VII-21 (p. 366) presents the treatment effectiveness corre-
sponding to the BAT treatment train for the pollutants selected.
Effluent concentrations (one day maximum and ten day average
values) are multiplied by the normalized discharge flows sum-
marized in Table VII-21 to calculate the mass of pollutants
allowed to be discharged per mass of product. The results of
these calculations are shown in Tables XII-2 through XII-25.
466
-------
Table XII-1
TOXIC ORGANIC POLLUTANTS SELECTED FOR REGULATION
FOR COPPER FORMING INDIRECT DISCHARGERS
4. benzene
11. 1,1,1-trichloroethane
23. chloroform
36. 2,6-dinitrotoluene
38. ethylbenzene
44. methylene chloride
55. naphthalene
62. N-nitrosodiphenylamine
78. anthracene
81. phenanthrene
86. toluene
87. trichloroethylene
467
-------
Table XII-2 .
PSES FOR HOT ROLLING SPENT' LUBRICANT
Pollutant or Pollutant Property
Maximum
For Apy
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Hot Rolled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Sc Grease (for alternate
monitoring)
0.044
0.20
0.016
o.is
044
0.032
2.06
0.018
0.11
0.014
0.11
0.058
0.025
1.24
Table XII-3
i
PSES FOR COLD ROLLING SPENT* LUBRICANT
Pollutant or Pollutant Property
Maximum
For Apy
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Cold Rolled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Sc Grease (for alternate
monitoring)
0.|L6
0.72
0.057
0.54
0.51
0.12
7.58
0.065
0.38
0.050
0.38
0.22
0.091
4.55
468
-------
Table XII-4
PSES FOR DRAWING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Drawn
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Se Grease (for alternate
monitoring)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table XII-5
PSES FOR SOLUTION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Sc Grease (for alternate
monitoring)
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Quenched in Water
0.27
1.23
0.097
0.91
0.86
0.20
12.92
0.11
0.65
0.084
0.65
0.36
0.16
7.75
469
-------
r
Table XII-6
PSES FOR EXTRUSION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Extruded
and Quenched in a Lubricant
Solution
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil St Grease (for alternate
monitoring)
0.00084
O.Ob38
0.00030
0.0028
0.0027
0.00062
0.040
0.00034
0.0020
0.00026
0.0020
0.0012
0.00048
0.024
Table XII-7 (
PSES FOR ANNEALING WITH WATER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in Water
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil St Grease (for alternate
monitoring)
0.52
2.36
0.19
1.75
1.6|5
0.38
24.80
0.21
1.24
0.16
1.24
0.70
0.30
14.88
470
-------
Table XII-8
PSES FOR ANNEALING WITH OIL
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in a Lubricant
Solution
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table XII-9
PSES FOR ALKALINE CLEANING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
Cleaned
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
1.77
8.01
0.63
5.94
5.60
1.31
84.28
0.72
4.21
0.55
4.21
2.36
1.01
50.57
471
-------
Table XII-10
PSES FOR ALKALINE CLEANING BATH
.NG
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
| Cleaned
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil St Grease (for alternate
monitoring)
0.020
0.089
0.0071
0.066
0.062
0.014
0.93
0.0080
0.047
0.0061
0.047
0.026
0.011
0.56
Table XII-11
PSES FOR PICKLING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium ,
Copper
Lead
Nickel
Zinc
TTO
Oil Se Grease (for alternate
monitoring)
0,
2,
1
1
55
48
0.20
.84
.74
0.41
26.12
0.22
1.31
0.17
1.31
0.73
0.31
15.67
472
_
-------
Table XII-12
PSES FOR PICKLING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
0.049
0.22
0.018
0.17
0.16
0.036
2.32
0.020
0.12
0.015
0.12
0.065
0.028
1.39
Table XII-13
PSES FOR PICKLING FUME SCRUBBER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Lead
Nickel
Copper
Zinc
TTO
Oil.& Grease (for alternate
monitoring)
0.26
1.19
0.094
0.88
0.83
0.19
12.51
0.11
0.63
0.082
0.63
0.35
0.15
7.51
473
-------
Table XII-14
PSNS FOR HOT ROLLING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Hot Rolled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Se Grease (for alternate
monitoring)
0.038
0.13
0.011
0.657
O.ll
0.022
1.03
Table XI1-15
i
PSNS FOR COLD ROLLING SPENT;LUBRICANT
0.016
0.063
0.0093
0.038
0.043
0.022
1.03
Pollutant or Pollutant Property
Maximum
For Ahy
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Cold Rolled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Sc Grease (for alternate
monitoring)
0.14
0.49
0.038
0.21
0.39
0.080
3.79
0.057
0.23
0.034
0.14
0.16
0.080
3.79
474
-------
Table XII-16
PSNS FOR DRAWING SPENT LUBRICANT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Drawn
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil 8e Grease, (for alternate
monitoring)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table XT.I-17
PSNS FOR SOLUTION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper
Quenched in Water
0.24
0.83
0.065
0.36
0.66
0.14
6.46
0.097
0.39
0.058
0.24
0.27
0.14
6.46
475
-------
•1
Table XII-18
PSNS FOR EXTRUSION HEAT TREATMENT
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Extruded
and Quenched in a Lubricant
i Solution
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil 8e Grease (for alternate
monitoring)
0.0
O.C
026
0.00020
0.6011
0.6021
0.60042
0.020
0.00030
0.0013
0.00018
0.00074
0.00084
0.00042
0.020
Table XII-19 \
PSNS FOR ANNEALING WITH WATER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in Water
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
0.46
1.59
0.13
0.68
147
0.26
12.40
0.19
0.76
0.12
0.46
0.52
0.26
12.40
476
-------
Table XII-20
PSNS FOR ANNEALING WITH OIL
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Annealed
and Quenched in a Lubricant
Solution
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table XII-21
PSNS FOR ALKALINE CLEANING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
Cleaned
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
1.56
5.39
0.42
2.32
4.30
0.89
42.14
0.63
2.57
0.38
1.56
1.77
0.89
42.14
477
-------
Table XII-22
PSNS FOR ALKALINE CLEANING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Alkaline
i Cleaned
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
o.oi?
0.060
0.0047
0.026
0.048
0.0099
0.47
0.0070
0.029
0.0042
0.017
0.020
0.0099
0.47
Table XII-23 !
PSNS FOR PICKLING RINSE
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Se Grease (for alternate
monitoring)
0.22
0.75
0.059
0.32
0.60
0.12
5.85
0.088
0.36
0.053
0.22
0.25
0.12
5.85
478
-------
Table XII-24
PSNS FOR PICKLING BATH
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil & Grease (for alternate
monitoring)
0.043
0.15
0.012
0.064
0.12
0.024
1.16
0.018
0.071
0.011
0.043
0.048
0.024
1.16
Table XII-25
PSNS FOR PICKLING FUME SCRUBBER
Pollutant or Pollutant Property
Maximum
For Any
One Day
Maximum for
Monthly Average
Milligrams Per Off Kilogram
(Ibs/million Ibs) of Copper Pickled
Chromium
Copper
Lead
Nickel
Zinc
TTO
Oil Sc Grease (for alternate
monitoring)
0.23
0.81
0.063
0.35
0.64
0.13
6.26
0.094
0.38
0.057
0.23
0.26
0.13
6.26
479
-------
-------
SECTION XIII
BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY
The 1977 amendments to the Clean Water Act added Section
301(b)(2)(E), establishing "best conventional pollutant control
technology" (BCT) for discharge of conventional pollutants from
existing industrial point sources. Biological oxygen-demanding
pollutants (BODs), total suspended solids (TSS), fecal coli-
form, oil and grease (O&G), and pH are considered by EPA to be
conventional pollutants (see 44 FR 50732).
BCT is not an additional limitation but replaces BAT for the con-
trol of conventional pollutants. In addition to other factors
specified in Section 304(b) (4) (B), the Act requires that BCT lim-
itations be assessed in light of a two part "cost-reasonableness"
test (American Paper Institute v. EPA, 660 F.2d 954 (4th Cir.
1981)). The first test compares the cost for private industry to
reduce its conventional pollutants with the costs to publicly
owned treatment works for similar levels of reduction in their
discharge of these pollutants. The second test examines the
cost-effectiveness of additional industrial treatment beyond BPT.
EPA must find that limitations are "reasonable" under both tests
before establishing them as BCT. In no case may BCT be less
stringent than BPT.
On October 29, 1982, the Agency proposed a revised BCT method-
ology. EPA is deferring proposal of BCT limitations for the
copper forming category until the revised methodology can be
applied to the technologies available for the control of con-
ventional pollutants in the copper forming category.
481
-------
-------
SECTION XIV
ACKNOWLEDGEMENTS
The initial draft of this document was prepared by Hamilton
Standard, a division of the United Technologies Corporation under
Contract No. 68-01-4408. The document has been checked and
revised at the specific direction of EPA personnel by Radxan
Corporation under Contract No. 68-01-6529.
The field sampling programs were conducted under the leadership
of Mr. Mark Hellstein of Hamilton Standard. Preparation and^
writing of the initial drafts of this document was accomplished
by Mr. Daniel Lizdis, Mr. Robert Blazer, Mr. Edward Hodgson and
Mr. Mark Hellstein. Mr. James Sherman, Program Manager, Mr. Mark
Hereth, Project Director, Mr. John Vidumsky and Mr. John Sheehan
have contributed in specific assignments in the final preparation
of this document.
The project was conducted by the Environmental Protection
Agency, Metals & Machinery Branch, Mr. Ernst P. Hall, Chief. The
technical project officer is Mr. Dave Pepson; the previous
technical project officer was Mr. John Williams. The project s
legal advisor is Ms. Jill Weller, who contributed to this
project. The economic project officer is Ms. Ann Catkins.
Contributions from the Monitoring & Data Support Division came
from Mr. Rich Healey.
The cooperation of the Copper and Brass Fabricators Council,
Incorporated, their technical committee and the individual copper
forming companies whose plants were sampled and who submitted
detailed information in response to questionnaires is gratefully
appreciated.
Acknowledgement and appreciation is also given to the secretarial
staff of Radian Corporation (Ms. Nancy Reid, Ms. Sandra Moore and
Ms. Debbie Dodd and to the word processing staff of the Effluent
Guidelines Division (Ms. Pearl Smith, Ms. Carol Swann, and Ms.
Glenda Nesby) for their efforts in the typing of drafts,
necessary revisions, and preparation of the effluent guidelines
document.
483
-------
, ,, - ,
-------
SECTION XV
GLOSSARY
This section is an alphabetical listing of technical terms (with
definitions) used in this document which may not be familiar to
the reader.
4-AAP Colorimetric Method
An analytical method for total phenols and total phenolic com-
pounds that involves reaction with the color developing agent
4-aminoantipyrine.
Some
Acid Dip
Using any acid for the purpose of cleaning any material,
methods of acid cleaning are pickling and oxidizing.
Acidity
The quantitative capacity of aqueous solutions to react with
hydroxyl ions. Measured by titration with a standard solution of
a base to a specified end point. Usually expressed as milligrams
per liter of calcium carbonate.
The Act
The Federal Water Pollution Control Act Amendments of 1972 as
amended by the Clean Water Act of 1977 (PL 92-500).
Aging
A change in the properties of certain metals and alloys that
occurs at ambient or moderately elevated temperatures after hot
working or heat treatment (quench aging in ferrous alloys,
natural or artificial aging in ferrous and nonferrous alloys) or
after a cold working operation (strain aging). The change in
properties is often due to a phase change (precipitation), but
never involves a change in chemical composition of the metal or
alloy.
Alkaline Cleaning
A proces where dirt, mineral and animal fats, and oils are
removed from the metal surface by exposure to solutions at high
temperatures containing alkaline compounds, such as caustic soda,
soda ash, alkaline silicates, and alkaline phosphates.
485
-------
Alkalinity
The capacity of water to neutralize acids, a property imparted by
the water's content of carbonates, bicarbonates, hydroxides, and
occasionally borates, silicates', and phosphates. It is measured
by titration with a standardized acid to a specified end point,
and is usually reported in milligrams per liter of calcium
carbonate. •
Amortization :
i
The allocation of a cost or account according to a specified
schedule, based on the principal, interest and period of cost
allocation.
i
Analytical Quantification Level
i
The minimum concentration at which quantification of a specified
pollutant can be reliably measured. ',
Annealing . ; . .
A generic term describing a metals treatment process that is used
primarily to soften metallic materials, but also to simultane-
ously produce desired changes in other properties or in micro-
structure. The purpose of such changes may be, but is not
confined to, improvement of machinability, facilitation of cold
work, improvement of mechanical or electrical properties, and/or
increase in stability of dimensions. Annealing consists of heat-
ing and cooling the metal at varying rates to achieve the desired
properties. ,
Backwashing
The operation of cleaning a filter or column by reversing the
flow of liquid through it and washing out matter previously
trapped.
Batch Treatment
A waste treatment method where wastewater is collected over a
period of time and then treated prior to discharge. Treatment: is
not continuous, but collection may be continuous.
Bench-Scale Pilot Studies
Experiments providing data concerning the
wastewater stream or the efficiency of a
ducted using laboratory-size equipment.
treatability of a
treatment process con-
486
-------
Best Available Demonstrated Technology (BADT)
Treatment technology upon which new source performance standards
are based as defined by Section 306 of the Act.
Best Available Technology Economically Achievable (BAT)
Level of technology applicable to toxic and nonconventional pol-
lutants on which effluent limitations are established. These .
limitations are to be achieved by July 1, 1984 by industrial dis-
charges to surface waters as defined by Section j01(b;U.KW ot
the Act.
Best Conventional Pollutant Control Technology (BCT)
Level of technology applicable to conventional pollutant effluent
limitations to be achieved by July 1, 1984 for industrial dis-
charges to surface waters as defined in Section 301(b;(Z)(£) ot
the act.
Best Management Practices (BMP)
Regulations intended to control the release of toxic and hazard-
ous pollutants from plant runoff, spillage, leaks, solid waste
disposal, and drainage from raw material storage.
Best Practicable Control Technology Currently Available (BPT)
Level of technology applicable to effluent limitations to have
been achieved by July 1, 1977 (originally) for industrial dis-
charges to surface waters as defined by Section 301(b)Cl)(A; ot
the Act.
Billet
A long slender cylindrical cast product used as raw material in
subsequent forming operations.
Biochemical Oxygen Demand (BOD)
The quantity of oxygen used in the biochemical oxidation of^
organic matter under specified conditions for a specified time.
Slowdown
The minimum discharge of circulating water for the purpose of
discharging dissolved solids or other contaminants contained in
the water, the further buildup of which would cause concentration
in amounts exceeding limits established by best engineering
practice.
487
-------
Catalyst
An agent that (1) reduces the energy required for activating a
chemical reaction and (2) is not consumed by that reaction.
Chelation
The formation of coordinate covalent bonds between a central
metal ion and a liquid that contains two or more sites for com-
bination with the metal ion.
Chemical Finishing
Producing a desired finish on the surface of a metallic product
by immersing the workpiece in a chemical bath.
!
Chemical Oxygen Demand (COD)
A measure of the oxygen-consuming capacity\of the organic and
inorganic matter present in the water or wastewater.
Colloid
[
i
Suspended solids whose diameter may vary between less than one
micron and fifteen microns.
Composite Samples
A series of samples collected over a period of time but combined
into a single sample for analysis. The individual samples can be
taken after a specified amount of time has;passed (time compo-
sited), or after a specified volume of water has passed the sam-
pling point (flow composited). The sample can be automatically
collected and composited by a sampler or can be manually
collected and combined.
Consent Decree (Settlement Agreement)
Agreement between EPA and various environmental groups, as insti.-
tuted by the United States District Court for the District of
Columbia, directing EPA to study and promulgate regulations for
the toxic pollutants (NRDC, Inc. v. Train. 8 ERG 2120 (D.D.C.
1976), modified March 9, 1979, 12 ERG 1833).
Contact Water
Any water or oil that comes into direct coritact with the copper
or copper alloy, whether it is raw material, intermediate
product, waste product, or finished product.
488
iir ';,'!!."! .;'.. ''iiHi ;;;'<> o/fcicMOff1 v* • ,n|
"11,1 "illim;" IK; I "i »" ,""11 ,' i ill" i '"' I » ,'"" ,' .minus1,"'II, |"i I", i "I'll,, Ai'iini 'illlE'lviILn ' iii, ':,! 'fill
""i'i:,'"'(:;'a'' [,""!i-!'i"!|i, !"n-|l'j i'il •••; ,,"'> J i' It ,'• ,, .. "..aw B lit ', !'""»il I
n'n.. ,|!"ll. . r'l .I'l.: '! .111. I T- ."i.
'liiil'li',,' '! ,i-i,'J", "i:>i 'llii'i:,"',: "II , i "
-------
Continuous Casting
A casting process that produces sheet, rod, or other long shapes
by solidifying the metal while it is being poured through an
open-ended mold using little or no contact cooling water. Thus,
no restrictions are placed on the length of the product and it is
not necessary to stop the process to remove the cast product.
Continuous Treatment
Treatment of waste streams operating without interruption as
opposed to batch treatment. Sometimes referred to as flow-
through treatment.
Contractor Removal (Contractor Hauling)
Disposal of oils, spent solutions, or sludge by a commercial
firm.
Conventional Pollutants
Constitutents of wastewater as determined by Section 304(a)(4) of
the Act, including pollutants classified as biological-oxygen-
demanding, oil and grease, suspended solids, fecal coliforms, and
pH.
Cooling Tower.
A hollow, vertical structure with internal baffles designed to
break up falling water so that it is cooled by upward-flowing air
and the evaporation of water.
Counter Current Cascade Rinsing
A staged process that employs recycled, often untreated water as
a rinsing medium to clean metal products. Water flow is opposite
to product flow such that the most contaminated water encounters
incoming product first.
Data Collection Portfolio (dcp)
The questionnaire used in the survey of the copper forming
industry.
Desmutting
A process that removes a residual silt (smut) by immersing the
product in an acid solution, usually nitric acid.
489
-------
Direct Chill Casting
A method of casting where the molten copper, is poured into a
water-cooled mold. The base of this mold is the top of a
hydraulic cylinder that lowers the copper first through the mold
and then through a water spray and bath to cause solidification.
The vertical distance of the drop limits the length of the ingot,
This process is also known as semi-continuous casting.
Direct Discharger i
]
Any point source that discharges to a surface water (river, lake
or stream).
Dragout
I
The solution that adheres to the objects removed from a bath or
rinse, more precisely defined as that solution which is carried
past the edge of the tank.
Drawing
[
Pulling the metal through a die or succession of dies to reduce
the diameter or alter the shape of the metal.
Drying Beds
Areas for dewatering of sludge by evaporation and seepage.
Effluent
Discharge from a point source.
Effluent Limitation
_^_^———————— I
Any standard (including schedules of compliance) established by a
state or EPA on quantities, rates, and concentrations of chemi-
cal, physical, biological, and other constituents that are dis-
charged from point sources into navigable waters, the waters of
the contiguous zone, or the ocean.
Electrostatic Precipitator (ESP)
A gas cleaning device that induces an electrical charge on a
solid particle which is then attracted to an oppositely charged
collector plate. The collector plates are intermittently
vibrated to discharge the collected dust to a hopper.
490
-------
Emulsifying Agent
A material that increases the stability of a dispersion of one
liquid in another.
Emulsions
Stable dispersions of two immiscible liquids.
End-of-Pipe Treatment
The reduction of pollutants by wastewater treatment prior to dis-
charge or reuse.
Extrusion
A process in which high pressures are applied to a billet of
copper, forcing the copper to flow through a die orifice.
Finishing
The coating or polishing of a metal surface.
Forging
A process that exerts pressure on die or rolls surrounding heated
aluminum stock forcing the stock to take the shape of the dies.
Gas Chromatography/Mass Spectroscopy (GC/MS)
Chemical analytical instrumentation used for quantitative organic
analysis.
Grab Sample
A single smample of wastewater taken without regard to time or
flow.
Heat Treatment
A process that changes the physical properties of the metal, such
as strength, ductility, and malleability by controlling the rate
of cooling.
Indirect Discharger
Any point source that discharges to a publicly owned treatment
works.
491
-------
Inductively-Coupled Argon Plasma Spectrophotometer (ICAP)
i
A laboratory device used for the analysis of metals.
Ingot
A large, block-shaped casting produced by various methods.
Ingots are intermediate products from which other products are
made. ;
In-Process Control Technology ',
Any procedure or equipment used to conserve chemicals and water
throughout the production operations, resulting in a reduction of
the wastewater volume.
New Source Performance Standards (NSPS)
Effluent limitations for new industrial point sources as defined
by Section 306 of the Act.
Nonconventional Pollutant
i
Parameters selected for use in performance standards that have
not been previously designated as either conventional or toxic
pollutants.
Non-Water Quality Environmental Impact
The ecological impact as a result of solid, air, or thermal pol-
lution due to the application of various wastewater technologies
to achieve the effluent guidelines limitations. Also associated
with the non-water quality aspect is the energy impact of waste-
water treatment. !
NPDES Permits
Permits issued by EPA or an approved state program under the
National Pollution Discharge Elimination System.
Off-Gases i
Gases, vapors, and fumes produced as a result of an alximinum
forming operation. '.
Oil and Grease (O&G)
Any material that is extracted by freon from an acidified sample
and that is not volatilized during the analysis, such as hydro-
carbons, fatty acids, soaps, fats, waxes, and oils.
492
-------
El
The pH is the negative logarithm of the hydrogen ion activity of
a solution.
Pickling
The process of removing scale, oxide, or foreign matter from the
surface of metal by immersing it in a bath containing a suitable
chemical reagent that will attack the oxide or scale, but^will
not act appreciably upon the metal during the period of pickling.
Frequently it is necessary to immerse the metal in a detergent
solution or to degrease it before pickling.
Plate
A flat, extended, rigid body of copper having a thickness greater
than or equal to 6.3 mm (0.25 inches).
Pollutant Parameters
Those constituents of wastewater determined to be detrimental
and, therefore, requiring control.
Priority Pollutants
Those pollutants included in Table 2 of Committee Print number
95-30 of the "Committee on Public Works and Transportation of the
House of Representatives," subject to the Act.
Process Water
Water used in a production process that contacts the product, raw
materials, or reagents.
Production Normalizing Parameter (PNP)
The unit of production specified in the regulations used to
determine the mass of pollution a production facility may
discharge.
PSES
Pretreatment standards (effluent regulations) for existing
sources.
PSNS
Pretreatment standards (effluent regulations) for new sources.
493
-------
Publicly Owned Treatment Works (POTW) ;
I
A waste treatment facility that is owned by a state or
municipality. ,
Recycle •
Returning treated or untreated wastewater to the production pro-
cess from which it originated for use as process water.
Reduction
A reaction in which there is a decrease in valence resulting from
a gain in electrons.
Reuse i
!
The use of treated or untreated process wastewater in a different
production process.
Rinsing
A process in which water is used to wash pickling and cleaning
chemicals from the surface of metal.
Rolling
i
A forming process that reduces the thickness of a workpiece by
passing it between a pair of lubricated steel rollers.
Scrubber Liquor ;
The untreated wastewater stream produced by wet scrubbers clean-
ing gases produced by copper forming operations.
Seal Water j
j
A water curtain used as a barrier between the annealing furnance
atmosphere and the outside atmosphere. l
Semi-Fabricated Products ;
Intermediate products that are the final prbduct of one process
and the raw material for a second process. !
Stationary Casting
A process in which the molten copper is poured into molds and
allowed to air-cool. It is often used to recycle in-house scrap.
494
'! ' ,,"!i'lIII, ', :.!!! 'il'1' '" 'nlillli'".^ :'
-------
Strain-Hardening (see work-bardening)
Subcategorization
The process of segmentation of an industry into groups of plants
for which uniform effluent limitations can be established.
Surface Water
Any visible stream or body of water, natural or man-made. This
does not include bodies of water whose sole purpose is wastewater
retention or the removal of pollutants, such as holding ponds or
lagoons.
Surfactants
Surface active chemicals that tend to lower the surface tension
between liquids.
Swaging
A process in which a solid point is formed at the end of a tube,
rod or bar by the repeated blows of one or more pairs of oppos-
ing dies. It is often the initial step in the drawing process.
Total Dissolved Solids (TDS)
Organic and inorganic molecules and ions that are in true solu-
tion in the water or wastewater.
Total Organic Carbon (TOG)
A measure of the organic contaminants in a wastewater. The TOG
analysis does not measure as much of the organics as the COD or
BOD tests, but is much quicker than these tests.
Total Recycle
The complete reuse of a stream, with makeup water added for
evaporation losses. There is no blowdown stream from a totally
recycled flow and the process water is not periodically or con-
tinuously discharged.
Total Suspended Solids (TSS)
Solids in suspension in water, wastewater, or treated effluent.
Also known as suspended solids.
495
-------
Tubing Blank
A sample taken by passing one gallon of distilled water through a
composite sampling device before initiation of actual wastewater
sampling.
Volatile Substances
Materials that are readily vaporizable at relatively low
temperatures.
Wet Scrubbers
Air pollution control devices used for removing pollutants as the
gas passes through the spray.
Wire
A slender strand of copper with a diameter less than 9.5 mm (3/8
inches).
i
Work-Hardening
An increase in hardness and strength and a loss of ductility that
occurs in the workpiece as a result of passing through cold form-
ing or cold working operations. Also known as strain-hardening.
Zero Discharger
Any industrial or municipal facility that does not discharge
wastewater.
496
-------
SECTION XVI
REFERENCES
Adin, A., Baumarm, E. R., Cleasby, J. L., 1979, "The Application
of Filtration Theory to Pilot-Plant Design," Journal of the Amer-
ican Water Works Association, January.
Alloid Colloids, Inc. brochure.
American Society for Metals, 1964, Heat Treating, Cleaning, and
Finishing, Metals Handbook, 8th ed., Vol. 2, OH.
American Society for Metals, 1970, Forging and Casting, Metals
Handbook, 8th ed., Vol. 5, OH.
Amstead, B. H., Ostwald, P. F., Begeman, M. L., 1977, Manufactur-
ing Processes, 7th ed., John Wiley & Sons, NY.
API, 1969, Manual on Disposal of Refinery Wastes: Volume on
Liquid Wastes, 1st ed., American Petroleum Institute, Washington,
D.C.
Argo and Wesner, 1976, "AWT Energy Needs a Prime Concern," Water
and Wastes Engineering, 13:5:24.
Banerji and O1Conner, 1977, "Designing More Energy Efficient
Wastewater Treatment Plants," Civil Engineering ASCE, 47:7:76.
Bansal, I. K., 1977, "Reverse Osmosis and Ultrafiltration of Oily
and Pulping Effluents," Industrial Wastes, May/June.
Barnard, J. L., Eckenfelder, W. W. Jr., 1971, Treatment Cost
Relationships for Industria'
#23, Vanderbilt University.
Dcl.LLlCL.I-VJ.} »J • -LJ * y 1I*^E\.C;».1 J-d J.u^J. 9 »»• vi • w»^_»j — ^ , — 5 _ _ •—" — ;- — — —_
Relationships for Industrial Waste Treatment, Technical Report
Bauer, D., 1976, "Treatment of Oily Wastes—Oil Recovery Pro-
grams," Presented at 31st Annual Purdue Industrial Waste Confer-
ence.
Basselievre, E. B., Schwartz, M., 1976, The Treatment of Indus-
trial Wastes, McGraw-Hill Book Co., New York, NY.
Brody, M. A., Lumpkins, R. J. , 1977, "Performance of Dual Media
Filters," Chemical Engineering Progress, April.
Burns and Roe, 1979, Draft Technical Report for the Paint Indus-
try.
497
-------
Carborundum, 1977, "Dissolved Air Flotation Systems," December.
Catalytic, Inc., 1979, Treatment Catalogue for the Catalytic Com-
puter Model.
I
Chemical Marketing Reporter, March 17, 1978.
Cheremisinoff, P. N., Ellerbusch, F., 1978, Carbon Adsorption
Handbook, Ann Arbor Science, Ann Arbor, MI.
Chieu, J. H., Gloyna, E. F., Schechter, R. S., 1975, "Coalescence
of Emulsified Oily Wastewater by Fibrous Beds," Presented at the
30th Annual Purdue Industrial Waste Conference.
j
Clark, J. W., Viessman, W., Hammer, M. S., 1977, Water Supply and
Pollution Control, IEP-A Dun-Donnelley Publisher, New York, NY.
Gulp and Gulp, 1974, New Concepts in Water Purification, Van
Nostrand Reinhold, New York, NY.
Gulp, R. L., Wesner, G. M., Gulp, Gi L. , 1978, Handbook of
Advanced Wastewater Treatment, Van Nostrand Reinhold Company, New
York, NY. ;
Davies, B. T., Vose, R. W., 1977, "Custom Designs Cut Effluent
Treatment Costs, Case Histories at Chevron, U.S.A., Inc.," Purdue
Industrial Waste Conference, p. 1035. i
!
Denyo, D. J., ed., 1978, Unit Operations for Treatment of Hazard-
ous Wastes.
Dickey, 1970, "Managing Waste Heat with the Water Cooling Tower,"
Marley Co.
Dugas, R. S., Reed, P. E,,, 1977, "Successful Pretreatment and
Deep Well Injection of Chemical Plant Wastewater," Presented at
32nd Annual Purdue Industrial Waste Conference.
Dynatech RID Company, 1969, A Survey of Alternate Methods for
Cooling Condenser Discharge Water, Large-Scale Heat Rejection
Equipment, EPA Project No. 16130DH3.
Eckenfelder, W. W. Jr., O'Connor, D. J., 1961, Biological Waste
Treatment, Pergamon Press, NY.
Envirodyne, "Dissolved Air Flotation & Solids Settling - Model
Jupitor - 7,000."
Environmental Quality Systems, Inc., 1973, Technical and Economic
Review of Advanced Waste Treatment Processes.
498
-------
Federal Register, 43 FR 2150.
Federal Register, 44 FR 15926.
Federal Register> 44 FR 28716.
Federal Register, 44 FR 43660.
Federal Register, 44 FR 56628.
Ford, D. L., Elton, R. L., 1977, "Removal of Oil and Grease from
Industrial Wastewaters," Chemical Engineering, October 17, p. 49.
Gloyna, E. F., Ford, D. L., 1974, Cited by Osamor, F. A., Ahlert,
R. C., 1978, in Oil Water Separation: • State-of-the-Art, U.S.
Environmental Protection Agency, Cincinnati, OH, PB-28U 755.
Gross, A. C., 1979, "The Market for Water Management Chemicals,"
Environmental Science & Technology, 13:9:1050.
.Guthrie, K. M., 1969, "Capital Cost Estimating," Chemical Engi-
neering, March 24.
Hagan and Roberts, 1976, "Energy Requirements for Wastewater
Treatment Plants, Part 2," Water and Sewage Works, 124:12:52.
Hager, D. G., 1974, "Industrial Wastewater Treatment by GAC,"
Industrial Water Engineering, 11:1:18.
Hammer, M. J., 1975, Water and Wastewater Technology, John Wiley
& Sons, Inc., New York, NY.
Hawley, Gessner G., rev., The Condensed Chemical Dictionary, 9th
ed.
Hockenbury, M. R., Loven, A. W., 1977, "Treating Metal Forging
and Processing Wastewater," Industrial Wastes, 23:3:45.
Howes, Robert and Kent, Robert, 1970, Hazardous ^Chemicals
Handling and Disposal, Noyes Data Corp., Park Ridge, NJ.
Hsiung, K. Y., Mueller, H. M., Conley, W. R., 1974, "Physical-
Chemical Treatment for Oily Waste," Presented at WWEMA Industrial
Water Pollution Conference and Exposition, Detroit, MI, Cited by
Osamor, F. A., Ahlert, R. C., 1978, Oil/Water Separation: State-
of-the-Art, U.S. Environmental Protection Agency, Cincinnati, OH,
PB-280 755.
499
-------
Hutchins, R. A., 1975, "Thermal Regeneration Costs," Chemical
Engineering Prog., 71:5:80.
Industrial Water Engineering, 1970, "Cooling Towers - Special
Report," May.;
Infilco Degremont, Inc., 1974, "Sediflotor Clarifier," Company
Brochure DB830, September.
Jones, H. R., 1971, Environmental Control in the Organic and
Petrochemical Industries, Noyes Data Corp., Park Ridge, NJ.
Journal of Metal Finishing: "Guidelines for Wastewater Treat-
ment," September and October, 1977.
Katnick, K. E., Pavilcius, A. M., 1978, "AiNovel Chemical
Approach for the Treatment of Oily Wastewaters," Presented at
33rd Annual Purdue Industrial Waste Conference.
Kirk-Othmer, Encyclopedia of Chemical Technology, 2nd ed., 1963,
Interscience Publishers, New York, NY.
Koon, J. H., Adams, C. E. Jr., Eckenfelder, W. W., 1973,
"Analysis of National Industrial Water Pollution Control Costs,"
Associated Water and Air Resources Engineers, Inc.
Krockta, H., Lucas, R. L., 1972, "Information Required for the
Selection and Performance Evaluation of Wet Scrubbers," Journal
of the Air Pollution Control Association, June.
Kumar, J. I., Clesceri, N. L., 1973, "Phosphorus Removal from
Wastewaters: A Cost Analysis," Water Sc Sewage Works, 120:3:82.
i
Lacey, R. E., 1972, "Membrane Separation Processes," Chemical
Engineering, Sept. 4.
Lange, Norbert, Adolph, 1973, Handbook of Chemistry, McGraw-Hill,
New York, NY.
I
Lee, E. L., Schwab, R. E., 1978, "Treatment of Oily Machinery
Waste," Presented at 33rd Annual Purdue Industrial Waste Con-
ference, i
j
i
"Lime for Water and Wastewater Treatment: ^Engineering Data,"
BIF, Providence, Ref. No. 1.21-24. '
Lin, Y. G., Lawson, J. R., 1973, "Treatment of Oily and Metal
Containing Wastewater," Pollution Engineering, November.
500
-------
Lopez, C. X., Johnston, R., 1977, "Industrial Wastewater Recy-
cling with Ultrafiltration and Reverse Osmosis," Presented at the
32nd Annual Purdue Industrial Waste Conference.
Lund, H. F., ed.5 1971, Industrial Pollution Control Handbook,
McGraw-Hill Book Co., New York, NY.
Luthy, R. G., Selleck, R. E., Galloway, 1978, "Removal of Emulsi-
fied Oil with Organic Coagulants and Dissolved Air Flotation,
Journal Water Pollution Control Federation, 50:2:331.
Maeder, E. G., 1975, "The D&I Can: How & Why it Does More with
Less Metal," Modern Metals, August, pp. 55-62.
McKee, J. E. and Wolf, H. W., ed., 1963, Water Quality Criteria,
2nd ed., The Resources Agency of California, State Water Quality
Control Board, Publication No. 3-A.
t
McKinney, R. E., 1962, Microbiology for Sanitary Engineers,
McGraw-Hill Book Co., Inc., NY.
Myansnikov, I. N., Butseva, L. N., Gandurina, L. B., 1979, "The
Effectiveness of Flotation Treatments with Flocculants Applied to
Oil Wastewaters," Presented at USEPA Treatment of Oil Containing
Wastewaters, April 18 to 19, 1979, Cincinnati, OH.
National Commission on Water Quality, 1976, Water Pollution
Abatement Technology: Capabilities and Cost, PB-250 690-U3.
Nebolsine, R., 1970, "New Methods for Treatment, of Wastewater
Streams," Presented at 25th Annual Purdue Industrial Waste Con-
ference.
NTIS, 1974, Cost of Dissolved Air Flotation Thickening of Waste
Activated Sludge at Municipal Sewage Treatment Plants,
PB-226-582.
Osamor, F. A., Ahlert, R. C., 1978, Oily Water Separation:
State-of-the-Art, U.S. Environmental Protection Agency,
Cincinnati, OH, EPA-600/2-78-069.
Patterson, James W., Wastewater Treatment Technology.
Patterson, J. W., 1976, "Technology and Economics of Industrial
Pollution Abatement," Illinois Institute for Environmental Qual-
ity, Document No. 76/22.
Peoples, R. F., Krishnan, P., Simonsen, R. N., 1972, "Nonbiologi-
cal Treatment of Refinery Wastewater," Journal Water Pollution
Control Federation, November.
501
-------
Personal communication with Dave Baldwin or Tenco Hydro, Inc.
Personal communication with Jeff Busse of Envirex.
i
I
Personal communication with Envirodyne sales representative.
Personal communication with Goad, Larry and Company.
Personal communication with Kerry Kovacs of Komline-Sanderson.
Personal communication with Don Montroy of the Brenco Corporation
representing AFL Industries.
i
Personal communication with Jack Walters of Infilco-Degremont,
Inc.
t
Personal communication with Leon Zeigler of Air-o-Flow.
Pielkenroad Separator Company brochure.
I
Quinn, R., Hendershaw, W. K., 1976, "A Comparison of Current
Membrane Systems Used in Ultrafiltration and Reverse Osmosis,"
Industrial Water Engineering.
Richardson Engineering Services, Inc., 1980, General Construction
Estimating Standards, Solana Beach, CA.
Rizzo, J. L., Shephard, A. R., 1977a, "Treating Industrial Waste-
water with Activated Carbon," Chemical Engineering, January 3,
p. 95.
Rizzo, J. L., Shephard, A. R., 1977b, "Treating Industrial Waste-
water with Activated Carbon," Chemical Engineering, September 3.
Roberts, K. L., Weeter. D. W., Ball, R. 0., 1978, "Dissolved Air
Flotation Performance," 33rd Annual Purdue Industrial Waste Con-
ference, p. 194.
Sabadell, J. E., ed., 1973, Traces of Heavy' Metals in Water
Removal Processes and Monitoring, USEPA, 902/9-74-001.
Sawyer, C. N., McCarty, P. L., 1967, Chemistry for Sanitary
Engineering, McGraw-Hill Book Co., NY.
Sax, N. Irving, , Dangerous Properties of Industrial
Materials, Van Nostrand Reinhold Co., New York, NY.
Sax, N. Irving, 1974, Industrial Pollution, Van Nostrand Reinhold
Co., New York, NY.
502
-------
Sebastian, F. P., Lachtman, D. W. , Kominek, E., Lash, L., 1979,
"Treatment of Oil Wastes Through Chemical, Mechanical, and Ther-
mal Methods," Symposium; Treatment of Oil-Containing Wastewater,
April 18-19, Cincinnati, OH."
Seiden and Patel, Mathematical Model of Tertiary Treatment by
Lime Addition, TWRC-14.
Smith, J. E., 1977, "Inventory of Energy Use in Wastewater Sludge
Treatment and Disposal," Industrial Water Engineering, 14:4:20.
Smith, R., 1968, "Cost of Conventional and Advanced Treatment of
Wastewater," Journal Water Pollution Control Federation,
40:9:1546.
Sonksen, M. K., Sittig, M. F., Maziarz, E F., 1978, "Treatment of
Oily Wastes by Ultrafiltration/Reverse Osmosis - A Case History
Presented at 33rd Annual Purdue Industrial Waste Conference.
it
Spatz, D. D., 1974, "Methods of Water Purification," Presented to
the American Association of Nephrology Nurses and Technicians of
the NSAIO-AANNT Joint Conference, Seattle, Washington, April
1972, Revised July 1974.
Steel, E. W., I960, Water Supply and Sewerage, McGraw-Hill Book
Company, Inc., New York, NY.
Strier, M. P., 1978, "Treatability of Organic Priority Pollutants
- Part C - Their Estimated (30-Day Average) Treated Effluent Con-
centration - A Molecular Engineering Approach," Report to Robert
B. Schaffer, Director, EPA Effluent Guidelines Division, July 11;
and "Treatability of Organic Priority Pollutants - Part D - The
Pesticides - Their Estimated (30-Day Average) Treated Effluent
Concentration," December 26.
Symons, J. M., 1978, Interim Treatment Guide for Controlling
Organic Contaminants in Drinking Water Using Granular Activated
Carbon, Water Supply Research Division, Municipal Environmental
Research Laboratory, Office of Research and Development,
Cincinnati, OH.
Tabakin, R. B., Trattner, R., Cheremisinoff, P. N., 1978a,
"Oil/Water Separation Technology: The Options Available - Part
1," Water and Sewage Works, Vol. 125, No. 8, August.
Tabakin, R. B., Trattner, R., Cheremisinoff, P. N., 1978b,
"Oil/Water Separation Technology: The Options Available - Part
2," Water and Sewage Works, Vol. 125, No. 8, August.
503
-------
Thompson, C. S., 1972, "Cost and Operating :Factors for Treatment
of Oily Waste Water," Oil and Gas Journal, '70:47:53.
Throup, W. M., 1976, "Why Industrial Wastewater Pretreatment?"
Industrial Wastes, July/August, p. 32.
S
U.S. Department of Interior, FWPCA, 1967, industrial Waste
Profile No. 5 Petroleum Refining, Vol. III.
____ , !
U.S. Department of Interior, 1968a, Cost of Wastewater Treatment
Processes, TWRC-6.
U.S. Department of Interior, 1968b, Preliminary Design and
Simulation of Conventional Wastewater Renovation Systems Using
the Digital Computer, USDI-WP-20-9.•
i
U.S. Department of Interior, 1969, Appraisal of Granular Carbon
Contacting, Report No. TWRC-12.
U.S. Environmental Protection Agency, 1971a, Estimating Costs and
Manpower Requirements for Conventional Wastewater Treatment
Facilities, Water Pollution Control Research Series, 17090 DAN.
U.S. Environmental Protection Agency, 1971b, Experimental
Evaluation of Fibrous Bed Cpalescers for Separating Oil-Water
Emulsions,12050 DRC,November.
U.S. Environmental Protection Agency, 1973a, Capital and
Operating Costs of Pollution Control Equipment Module - Vol. II,
EPA-R5-73-023b.
U.S. Environmental Protection Agency, 1973b, Electrical Power
Consumption for Municipal Wastewater Treatment, EPA-R2-73-281.
i
U.S. Environmental Protection Agency, 1973c, Estimating Staffing
for Municipal Wastewater Treatment Facilities, EPA-68-01-0328.
U.S. Environmental Protection Agency, 1973d, Process Design
Manual for Carbon Adsorption, EPA-625/l-71-002a~^
U.S. Environmental Protection Agency, 1974c, Flow Equalization,
EPA-625/4-74-006.
U.S. Environmental Protection Agency, 1974d, Policy Statement on
Acceptable Methods of Utilization or Disposal or Sludges,
Washington, D.C..
U.S. Environmental Protection Agency, 1974g, "Wastewater
Filtration-Design Considerations," EPA Technology Transfer
Seminar Publication, July.
504
-------
U.S. Environmental Protection Agency, 1975a, A Guide to the
Selection of Cost-Effective Wastewater Treatment System,
EPA-430/9-75-002.
U.S. Environmental Protection Agency, 1975b, Costs of Wastewater
Treatment by Land Application, EPA-430/9-75-003, June.
U.S. Environmental Protection Agency, 1975c, Evaluation of Land
Application Systems, EPA-430/9-75-001, March.
U.S. Environmental Protection Agency, 1975d, Lime Use in
Wastewater Treatment Design and Cost Data, EPA-600/2-75-038.
U.S. Environmental Protection Agency, 1975e, Process Design
Manual for Suspended Solids Removal, EPA-625/l-75-003a.
U.S. Environmental Protection Agency, 1976a, Cost Estimating
Manual--Combined Sewer Overflow Storage and Treatment,
EPA-600/2-76-286.
U.S. Environmental Protection Agency, 1976b, Land Treatment of
Municipal Wastewater Effluents. Design Factors - I, EPA Tech-
nology Transfer Seminar Publication.
U.S. Environmental Protection Agency, 1976c, Land Treatment of
Municipal Wastewater Effluents. Design Factors - II, EFA Tech-
nology Transfer Seminar Publication.
U.S. Environmental Protection Agency 1976d, Land Treatment of
Municipal Wastewater Effuents. Case Histories, EPA Technology
Transfer Seminar Publication.
U.S. Environmental Protection Agency, 1977b, Controlling
Pollution from the Manufacturing and Coating of Metal Products:
Water Pollution Control, Technology Transfer, May,
EPA-625/3-77-009.
U.S. Environmental Protection Agency, 1977d, State-of-the-Art of
Small Water Treatment Systems, Office of Water Supply.
U.S. Environmental Protection Agency, 1977e, Supplement for
Pretreatment to the Development Document for the Petroleum '
Refining Industry Existing Point Source Category, March.
U.S. Environmental Protection Agency, 1978a, Analysis of
Operation and Maintenance_Costs for Municipal Wastewater
Treatment Systems, EPA-430/9-77-015"!
U.S. Environmental Protection Agency, 1978b, Construction Costs
for Municipal Wastewater Conveyance System: 1973-1977^
EPA-430/9-77-014.
505
-------
U.S. Environmental Protection Agency, 1978c, Construction Costs
for Municipal Wastewater Treatment Plants: 1973-1977,
EPA-430/9-77-013.
l
U.S. Environmental Protection Agency, 1978e, Estimating Costs for
Water Treatment as a Function of Size and Treatment Plant
Efficiency, EPA-600/2-78/182.
U.S. Environmental Protection Agency, 1978f, Innovative and
Alternative Technology Assessment Manual, EPA-430/9-78-009.
U.S. Environmental Protection Agency, 1978g, Process Design
Manual for Municipal Sludge Landfills, USEPA Technology Transfer,
EPA-625/1-78-010, SW-705, October.
U.S. Environmental Protection Agency, 1978h, Revised Economic
Impact Analysis of Proposed Regulations on Organic Contamination
Drinking Water, Office of Drinking Water.
i
U.S. Environmental Protection Agency, 1979a, Dissolved Air
Flotation of Gulf Shrimp Cannery Wastewater, EPA-600/2-79-061.
U.S. Environmental Protection Agency, 1979d, Process Design
Manual for Sludge Treatment and Disposal, EPA-625/1-79-Oil,
September. ;
!
U.S. Environmental Protection Agency, U.S. ,Army Corps of
Engineers, U.S. Department of Agriculture, 1977, Process Design
Manual for Land Treatment of Municipal Wastewater,
EPA-625/1-77-008, October.
Verschueren and Karel, 1972, Handbook of Environmental Data on
Organic Chemicals, Van Nostrand Reinhold Co., New York, NY.
Wahl, J. R. , Hayes, T. C., Kleper, M. H., Pinto, S. D. , 1979,
"Ultrafiltration for Today's Oily Wastewaters: A Survey of
Current Ultrafiltration Systems," Presented at 34th Annual Purdue
Industrial Waste Conference. ;
Wastewater
Water Pollution Control Federation, 1977, MOP/8:
Treatment Plant Design, WPCF, Washington, D.C.
!
Wyatt, M. J., White, P. E. Jr., 1975, Sludge Processing,
Transportation, and Disposal/Resource R~ecovery: A Planning
Perspective, Report No. EPA-WA-75-R024, December.
,
Zievers, J. F., Grain, R. A., Barclay, F. G., 1968, "Waste
Treatment in Metal Finishing: U.S. and European Practices,"
Cited by Technology and Economics of Industrial Pollution
Abatement^Illinois Institute for Environmental Quality,Document
No.76/22. as well as other pollutants including halogenated
organics.
506
-------
-------
United States
Environmental Protection
Agency
Official Business
Penalfy for Private Use
$300
Washington DC 20460
-------