EPA/540/2-89/048
SUPERFUNDTREATABILITY
CLEARINGHOUSE
Document Reference:
Research Triangle Institute. Information: "Input/Output Data for Several Treatment
Technologies." Center for Hazardous Material Research. 10 pp. May 1987.
EPA LIBRARY NUMBER:
Super-fund Treatability Clearinghouse -FCSP-1
-------
SUPERFUND TREATABILITT CLEARINGHOUSE ABSTRACT
Treatment Process:
Media:
Document Reference:
Document Type:
Contact:
Site Name:
Location of Test:
Physical/Chemical - Low Temperature Thermal
Stripping
Sludge/Oily
Research Triangle Institute. Information: "Input/
Output Data for Several Treatment Technologies."
Center for Hazardous Material Research. 10 pp.
May 1987.
EPA ORD Report
Dr. Clark Allen
Research Triangle Institute
P.O. Box 12194
Research Triangle Park, NC 27709
919-541-5826
Luva Corp., Charlotte, NC (Non-NPL)
Charlotte, NC
BACKGROUND; This treatability study is a pilot-scale evaluation of a
thin-film evaporator (TFE) for volatile organics (VO) removal from oily
sludges such as refinery sludges. TFEs were studied to evaluate their use
to remove and recover VO from these sludges prior to land treatment. This
would reduce the amount of VO available for release during land treatment
of the sludges. The process can also be operated to remove water and low
boiling point oils, reducing sludge volume while recovering oil from the
sludges prior to disposal. The organics were recovered as a condensate and
recycled to the petroleum refinery as product.
OPERATIONAL INFORMATION; The pilot-test was conducted September 8-12,
1986, on non-hazardous (as defined by RCRA) refinery wastes, similar to
hazardous refinery wastes such as API separator sludge. The TFE equipment
selected included a mechanical agitator device for producing and agitating
the film, permitting the processing of high viscosity liquids and sludges
with suspended solids. The mechanical agitation at the heat transfer
surface promotes heat transfer and maintains precipitated or crystallized
solids in manageable suspension without fouling the heat transfer surface.
A total of 22 runs were performed using two different wastes, three
temperatures, three flow rates and under both atmospheric and vacuum
conditions. Five 55-gallon drums of emulsion tank sludge were used on Test
1-18 while the balance of the tests were conducted on oily tank bottoms.
Temperatures used were 150°C, 230°C and 310°C. Flow rates of 70-150 Ib/hr
were evaluated. Sampling and analysis are discussed but no QA/QC is
reported.
PERFORMANCE; The fraction of feed removed by the TFE ranged from 11 to
95.7 percent. From 98.5 to 99.5 percent of the VO and 10 to 75 percent of
the semi-volatiles were removed from the sludge. Results for VO for the
extremes of feed rate and temperature range are provided in Table 1. The
3/89-34 Document Number: FCSP-1
NOTE: Quality assurance of data may not be appropriate for all uses.
-------
removal efficiency for volatiles was greater at higher temperatures. At
150°C some of the water in the feed was evaporated along with most of the
VO. At 320°C essentially all of the water and VO was removed along with
much of the higher boiling point oils. At this higher temperature, the
amount of bottom sludge produced ranged between 10 and 13 percent of the
feed rate, substantially reducing the amount of material to dispose of.
This sludge was still pumpable. The vacuum runs produced a milky-white
emulsion as condensate which would require further processing. At 320 C
the bottoms product was only 4.3 percent of the feed. This would indicate
a two stage process to first remove VO and semi-volatiles at atmospheric
pressure and then heavier oils under vacuum operation could substantially
reduce the amount of sludge material requiring disposal.
CONTAMINANTS:
Analytical data is provided in the treatability study report,
breakdown of the contaminants by treatability group is:
The
Treatability Group
W07-Heterocyclics and Simple
Aromatics
W08-Polynuclear Aromatics
W09-0ther Polar Organic
Organic Compounds
CAS Number
71-43-2
100-41-4
108-38-3
95-47-6
100-42-5
108-88-3
91-57-6
83-32-9
208-96-8
120-12-7
205-99-2
207-08-9
132-64-9
91-20-3
129-00-0
86-73-7
218-01-9
50-32-8
56-55-3
85-01-8
117-84-0
Contaminants
Benzene
Ethylbenzene
M-Xylene
O&P Xylene
Styrene
Toluene
2-Methylnaphthalene
Acenaphthene
Acenaphthylene
Anthracene
Benzo(B)fluoranthene
Benzo(K)fluoranthene
Dibenzofuran
Naphthalene
Pyrene
Flourene
Chrysene
Benzo(A)pyrene
Benzo(A)anthracene
Phenanthrene
Di-n-octylphthalate
3/89-34 Document Number: FCSP-1
NOTE: Quality assurance of data may not be appropriate for all uses.
-------
TABLE 1
TFE VOLATILE ORGANICS REMOVAL FOR SELECTED COMPOUNDS
Operating Conditions
Test
No.
5
7
8
10
Temperature
(*C)
150
150
310
310
Flow
rate
(Ib/hr)
71.6
153.7
68.5
143.4
Reduction in concentrations from feed (£)a
Benzene
99.58
99.73
99.72
99.76
Toluene
99.61
99.78
99.84
99.90
Ethylbenzene
99.48
98.83
99.68
99.78
m-Xylene
99.54
98.64
99.67
99.75
Notes: a) Based on GC/MS analysis.
b) This is a partial listing of data. Refer to the document for more
information.
3/89-34 Document Number: FCSP-1
NOTE: Quality assurance of data may not be appropriate for all uses.
-------
RESEARCH TRIANGLE INSTITUTE
Center for Hazardous Materials Research
Mr. Jack Campion
COM Federal Programs Corporation
1 Center Plaza
Boston, MA 02108
Dear Mr. Campion:
Enclosed is some additional information you requested. I hope you find
this information useful. The reports evaluating these processes will be
available upon request.
Please do not hesitate to call me at (919) 541-5826 if you wish to discuss
this information.
Very truly yours,
Clark Allen
CCA:fts
Enclosures
cc: C. W. Westbrook
Post Office Box 12194 Research Triangle Park, North Carolina 27709 Telephone- 919 541-6000
-------
-I- H
Ethylene dichloride
Chloroform
Benzene
Carbon tetrachloride
Chlorobenzene
1,1-Dichloroethane
1,1-Dichloroethene
1,2-Dichloroethene
Methylene chloride
Tetrachloroethene
1,1,2-THchloroethane
Trlchloroethene
Vinyl chloride
5,630
271
0.27
0.38
8.9
1.2
?!s
8.*4
0.097
9.6
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
ofiO a
o
t I
Kethylene chloride
Chlorofomi
Carbon tetrachloride
Chloromethane
Trichloroethylene
1,1,2-Trichloroethane
0.011
0.006
<0.005
<0.005
<0.005
<0.005
ce>i
A
7
0.031
n&
-------
M-
I
i-i
fl.
-_
*
w
<3
^
t
(/)
<-
^>
-V
e
--)
i \
v
%
v^.
1
1
-f
«
k.
-*i
«
I
0* O W
%
C C JO C »..£ X
* X » >
M«3».I.KIX*
1 0 > 0 1 - « 1
IDMI-11JM E OZd
J>
in
1*
NIOttV Bf^^ttt^ 9Oll*»
* *^ * «*O^- ^ C^OOtOCDCDfOOlCM^VC^^CM
c r-4 r-« CN (N r- r- U>CM
a>
c^
10 W V >^
^ -«
«
c
c
5 . Ill x
^ c ~ x x *> c
^ sji^'S x c c
. S5S»* c « c < c
e x "xi-ue c «i >, « u c
a x CL o o c N c c -n X D i.
t- ! "S J e 7.C C a ' 9C«vc * >»x: j: o c *»
w£«.*Sx» A v XX^ . cncj>co>,xxao.N0c
xx ee«>v c o ^> jr . «KC c X*>-t>«o«cc«
a a LC**-'»O «-»«-'^^ i Kia3xi->.ix0cci>oc
?! i^JrSS'rSSSi CI JCXXaQ.2»«jQ3*
»»j>5z»7>I!cLicce «io*>4>i - « i u u j:
oo IXCK«X ! tDCWt-LL/weo2CM-<-<«>ro^
W «-<*> »«-*>
u x c c
*>
L X 1. 1. C
x a. o o
*> 3 3 L
C X
c >>*- v- a
/-^ > »> »^^^^\
U C O JO JC
^ O v^^v^
C C O VI 1 O O O
*> i. c t. i e c c
cx«x
UQCD
M- 2
5
-t
-, 3 &
3 o
-------
5
^
II
» a>
« M
O> «
is
(O 61 S «S>
OQ
ro
(M
O CJ (S CM
oj
61
a
U
a
o
o
4-
C
.
1 | - *
1
^
1
-t
>~
>
5
M
^ ^
-t-
5
t
-f-
i
-fc
f7
*
^3
^
o
1
v> £
0
C 0
0
c
0
.c
V
4> C
X. 0
a
c
X
XX X
X +> *>
1 X 0
a 0.3:
- 1
0 Z CM
»N
,\
AcenapM
0 C
c
.1 »
AcenapM
Dibenzoi
c
0
t_
0
3
U.
c
f-
Phenantl
a
Anthraci
0
c
u
M
*>
c
X"\
000
*> C C
0 0
£ Ji
X. C C
4> 0
X U C C
o. o o 0
3 3 «-
X
XV- V- 0-
f *> s-*'I^'~*
CO ^^^
c "o" M i ooo
D H X C M N M
U C 1. 1 C C C
^ f £ 000
CL co o Q oo CD co
_
«
c
« « «
CM C -
0 C 0
C t> « C
C C M C 0 >,
« K 0 X
N 0 3 >> U >, 1
c i .c xx a
c i o *> *> i
OQ CM 1- UJ to E O
~ -
o
c
0
~
L (
1
I
\
1
1
1
0 0
)
'
QL
-
K
;
>
P
:
J
r -
>
: .
a.
>%
.
> i
>
r '
» .
»
L
>
y
>
> <
» .
j i
^ -o-o
c e
fX « 4J C C
c »
^ C X JC
4> 4>
>. U X C C
XX* «>
O-»C LXllC
C X00C 0 X O.OO0
r 0 a C C 4> 3 3 U
-x C « >, C L. 0* C X
: « c x -c 3 c c xv. v- o.
> *>*>««-0X0 ^.0*» X-N^N^-.
>ax,xxoc-»>u cu^tje*
XX 3.0.N0CM0^'0O v^v_^x^
l«>^>«igCLICI.COWI O O O
-X OCC0OCX0NXC»4NKI
ia^00j}3»^i.ct. i ccc
< 1 OU XCX0X 000
)Z(M<ro
c
«
V.
-^
q>
v
~+-
?
c
0
V.
V)
3
^
3
Q
1
^
aa
c^r
V
o
-------
RTI 472U-2500-36
472U-2500-47
EPA Contract No. 68-03-3149
Interim Report on the Feasibility of Using U.V. Photolysis and APEG
Reagent for Treatment of Dioxin Contaminated Soils.
Alkali Polyethylene Glycolate (APEG) was field tested at Shenandoah
Stables, Moscow Mills, Missouri, to evaluate its potential to dechlorinate
2,3,7,8-tetrachlorodibenzo-p-dioxin 12^1^8-TCDD] under ambient conditions.
The U.S. Environmental Protection Agency sampled the site in May and June
1982. The results indicated that the soil contamination in the arena ranged
from 1 to 127 parts per billion (ppb) in the top 30 inches of soil. In
addition, dust taken from tne spectator bleachers contained 110 ppb of dioxin.
An experimental design employing a Latin square was used by RTI to compare 5
levels of treatments. The treatments were designated: (1) APEG treated and
covered, (2) APEG treated and uncovered, (3) not treated and covered, (4) not
treated and uncovered, and (5) MPEG control and uncovered. Four separate
applications were made to each treatment level. The average of plot-specific
dioxin concentrations from treatment time 1 to treatment time 4 are as
follows:
Dioxin concentrations ppb
Treatment Time 1 Time 4 ,,,
1 88.5 75.8
2 92.1 79.6
3 96.2 127.8
4 92.3 143.6
5 97.1 89.2
No cost data for full-scale testing is available through this study since
the design was to compare the effectiveness of the five levels of treatment.
-------
RTI 471U-3065-34
EPA Contract No. 68-02-3992
Application of a Heated In-situ j\PEG Treatment Process to Decontaminate
RGB-Contaminated SoilA Case Study
Alkali polyethylene glycolate complexes (APEGs) were applied in situ to
drummed PCB-contaminated soils utilizing the Terraclene-Cl APEG process
developed by Galson Research Corporation. RTI documented the case history of
the PCB contaminated site, initial remedial efforts, and evaluated the
implementation of the Terraclene-Cl process as final remediation for the site.
Initial PCB concentrations ranged from £1 to 195 pom before treatment and 8.9
Drums above 50 ppm were retreated until
concentrations were reduced to below 50 ppm. Costs for this treatment were
originally to be S553 per drum or $2-8RQ per m3 nf «?nil. Actual costs
incurred after treatment were $5,066 per m3 of soil. The higher costs were
attributable to the pijot scale nature of the study.
-------
-TSl -
PILOT-SCALE EVALUATION OF A THIN-FILM EVAPORATOR FOR VOLATILE ORGANIC REMOVAL
FROM LAND TREATMENT SLUDGES
Coleen M. Northeim, C. Clark Allen, and Scott M. Harkins
Research Triangle Institute
P. 0. Box 12194
Research Triangle Park, North Carolina 27709
ABSTRACT
The U.S. Environmental Protection Agency Office of Air Quality Planning and Standards
is currently developing regulations to control air emissions from waste treatment, stor-
age, and disposal facilities. In support of this regulatory development effort, the
Research Triangle Institute has conducted a study of thin-film evaporators (TFE) for
removing volatile organics (VO) from refinery wastes. Thin-film evaporators were studied
to evaluate their use to remove and recover VO from waste petroleum sludges prior to land
treatment. This would reduce the amount of VO available for release to the atmosphere
during land treatment of the sludges.
The treatment of two refinery sludges was investigated in a pilot-scale agitated TFE.
The fraction of feed removed by the TFE ranged from 11 to 95.7 percent. At the greatest
overhead fraction, more than 99.9 percent of the VO and 75 percent of the semi volatile
compounds were removed from the sludge. At the lowest overhead fraction, greater than
98.5 percent of the VO and 10 to 43 percent of the semivolatiles were removed from the
sludge. The sludge processed with the lowest overhead fraction contained water and
maintained suitable handling characteristics for land treatment.
INTRODUCTION
The TFE test was conducted at Luwa
Corporation in Charlotte, NC, during the
week of September 8-12, 1986. Due to
regulatory constraints, the wastes that
were tested were nonhazardous (as defined
by RCRA) refinery wastes. These wastes
were selected based on their similarity to
hazardous refinery wastes, such as API
separator sl"dge (hazardous waste code
K051), that .ire currently land-treated.
The use of TFEs was investigated to
determine if VO can be removed and
recovered from waste petroleum sludges
prior to land treatment of the sludge.
This would reduce the amount of VO avail-
able for release to the atmosphere during
land treatment of the sludges. The VO
would be recovered as an organic conden-
sate and recycled to petroleum refineries
as product. In addition to VO removal,
the process can also be operated to remove
water and low boiling oils from sludges,
reducing sludge volume while recovering
oil from sludges prior to disposal. These
benefits are not limited to sludges dis-
posed of by land treatment.
-------
THIN-FILM EVAPORATION
Agitated TFEs are designed to spread a
thin layer of viscous liquids or sludges
on one side of a metallic surface with
heat supplied to the other side. This
promotes the transfer of heat to the
material while simultaneously exposing a
large surface for evaporation of volatile
compounds. Heat can be supplied by either
steam or heated oil; heated oils are used
to heat the waste to temperatures higher
than cSn be achieved with saturated steam.
Volatile constituents separate from the
feed liquid or sludge, producing a vapor
stream of volatiles and leaving a treated
waste which flows out of the bottom of the
evaporator. Vapors can be condensed and
recovered.
The unique feature of this equipment
is not the thin film Itself (falling- and
rising-film evaporators use thin liquid
layers), but rather the mechanical agi-
tator device for producing and agitating
the film. This mechanical agitator per-
mits the processing of high-viscosity
liquids and sludges with suspended solids.
The agitation at the heat transfer surface
not only promotes heat transfer but also
maintains precipitated or crystallized
solids in manageable suspension without
fouling the heat transfer surface.
With typical tip speeds of 900 to
1,200 cm/s (30 to 40 ft/s), centrifugal
forces distribute the feed as a thin film
on the heated cylinder wall, and the wave
action produced by the rotating blades
provides rapid mixing and frequent surface
regeneration of the thin liquid layer on
the transfer surface. A typical vertical
thin-film evaporator is Illustrated in
Figure 1.
PILOT FACILITY AND TEST
The tests were conducted at the pilot
facility of Luwa Corporation, Charlotte,
NC. This facility contains a variety of
evaporators produced by the company and is
used to test potential applications of
their equipment for clients. The equip-
ment used for the tests was judged most
suitable for our appHcat.ons. Samples of
tank bottoms sludges were obtained from an
oil refinery, tested in the equipment, and
then returned to the refinery for normal
disposal.
Drive
System
Rotor
Modular Heating
Bodies
Heating Medium |=
Product Outlet
Figure 1. Luwa vertical thin-film evaporator.
Figure 2 shows the equipment used in
the pilot-scale tests. The 100-gal feed
tank was agitated with both an axial mixer
and continuous recirculation of the feed
liquid through a centrifugal pump. A
positive displacement pump was used to
pump the feed sludge through the preheater
and into the top of the TFE. There, the
sludge was continuously spread over the
heated surface of the TFE. Unevaporated
material flowed down through the TFE to a
collection pot at the base. Materials
evaporating in the TFE passed through an
empty demister and were condensed in a
condenser that was cooled with cooling
tower water. Condensate flowed from the
condenser and was collected directly into
liquid sample jars or a flask used for
measuring condensate volumes. Any uncon-
densed vapors flowed from the condenser
through a wet testmeter for flow measure-
ment.
-------
Steam
100 Gallon
Feed Tank
Recirculation "oy,no
Feed
Pump n
Pump
Evacuated Pot
with 5 gallon bucket
intrainment
Separator
no demister pads)
. Condenser
(Water)
Vent
We,
Testmeter
To Vacuum
Process Streams:
F Feed
B Bottoms
C Condensate
V Vent
Figure 2. Configuration of test equipment.
-------
The TFE was heated by hot oil.
although steam could be used for lower
temperatures. Entrainment separators are
used frequently with TFEs to remove en-
trained liquids from the vapors flowing to
the condenser. The entrainment separator
was empty (but heated) during the testing,
and very little material condensed there.
Five feed lines from the preheater to the
TFE were heated with low-pressure steam,
as were the vapor lines from the TFE
through the entrainment separator and to
the condenser.
A total of 22 runs were performed with
the TFE, using two different wastes, three
temperatures, three flow rates, and under
both atmospheric and vacuum operation.
The feed rates and temperatures were
chosen to operate the TFE over its normal
range of operation and to demonstrate the
removal of VO compounds from the feed
sludges. Tests 1 through 18 used five
55-gal drums of an emulsion tank sludge
while tests 19 through 22 were performed
on oily tank bottoms. The process test-
ing, sampling, and analysis concentrated
on the tests using the first waste while
the second waste was used to gather addi-
tional process data and demonstrate proc-
ess operation on a second waste sludge.
Matrices indicating operating condi-
tions and run numbers for the tests are
shown in Table 1. This test plan studied
the two major variables affecting TFE
performance, the temperature of the heat-
ing jacket and the feed rate. The indi-
cated flows and temperatures were the
nominal process parameters during the
tests and the actual measured parameters
varied somewhat from these values. Runs
5, 6, and 7 were a series of tests at a
constant heating jacket temperature
(150 *C) at three different feed rates.
Runs 8, 9, and 10 were conducted at simi-
lar flow rates to Runs 5, 6, and 7 but
were at a much higher heating jacket tem-
perature (310 *C). Runs 14, 15, and 16
were conducted at an intermediate tempera-
ture (23'0 *C) and were limited to the two
lower flow rates. Runs 1-4, 12, and 13
were used as shakedown runs. These runs
allowed practice samples to be taken and
potential problems to be solved before the
samples to be analyzed were taken.
Three vacuum runs were performed with
the first waste sludge during Runs 11, 17,
and 18. The purpose of these runs was to
examine the effect of vacuum operation on
the removal of VO compounds from the feed
waste. The final four runs (19, 20, 21,
and 22) were performed with the second
waste. These tests were principally to
demonstrate the operation of the TFE with
a second waste sample and were not exten-
sively sampled and analyzed during the
project.
Four of the tests (5, 7, 8, and 10)
were selected for extensive sampling and
analysis of process streams. These four
runs allowed the process to be examined
with both high and low feed rates and at
both high and low heating temperatures.
They represent the range of reasonable
operating conditions for the TFE process-
ing waste sludges for the removal of vola-
tiles, water, and oils from the sludge.
SAMPLING AND ANALYSIS
Samples were taken to characterize the
wastes treated during the pilot studies
and to determine the efficiency of the TFE
process. Four process streams were
sampled: feed, bottoms, condensate, and
condenser vent gas. The procedures for
obtaining these samples are outlined in a
specific test and quality assurance plan.
In all cases, special precautions were
taken to obtain representative samples and
to prevent the loss of VO from the samples
prior to analyses.
Sample analysis was performed onsite
by RTI and offsite by contract labora-
tories. The onsite measurements performed
by RTI were: (1) the analysis of head-
space concentrations of VO from feed
sludge samples and bottoms samples and
(2) the measurement of vent gas flow rates
and overall VO concentrations in the vent
gas and bottoms collection pot. Two types
of analyses for headspace concentrations
of VO were employed. The first used
syringes to transfer gas samples from
half-filled sample bottles and a portable
GC to measure the concentrations of VO in
air above the samples. The second method
of measuring the headspace concentrations
of VO used a calibrated total hydrocarbon
anaTyzer. This instrument was a Bacharach
TLV Sniffer that pulls a continuous sample
that is continuously oxidized by a
catalyst-coated resistance element. The
resistance of this element varies with
-------
TABLE 1. THIN-FILM EVAPORATOR TEST PLAN
Feed No. 1, Emulsion Tank Bottoms
Flow Rate (Ib/hr)
70
100
150
Run 5
Run 6
Temperature (*C)
230
Run 14
Run 15
Run 16
310
Run 8
Run 9
150 Run 7 Run 10
Feed No. 2. Oily Tank Bottoms
Temperature (*C)
Flow Rate (Ib/hr) 150 310
45 Run 21 Run 19
80 Run 22 Run 20
-------
temperature, which 1s 1n turn proportional
to the hydrocarbon concentration of the
analyzed gas. These measurements were
intended to be a rough analysis of head-
space concentrations and to confirm the
results from GC analysis. The Bacharach
TLV Sniffer had a maximum measurable con-
centration of 10,000 ppm. This limit was
exceeded in the headspace of all of the
feed samples.
The Bacharach TLV was also used to
measure concentrations of organics in the
vent gas, feed tank headspace, and vapors
above the bottoms when the sample pot was
removed from the TFE. Measured organic
concentration of the vent gas and feed
tank headspace also exceeded the range of
the instrument.
Samples of the TFE feed, bottoms, and
condensate from selected tests were ana-
lyzed by a contract laboratory for vola-
tile and semivolatile organics; percent
oil, solids, and water; and metals using
the EPA Contract Laboratory Program (CLP).
The purpose of these analyses was to
evaluate the process effectiveness on an
individual component basis and to obtain
information to calculate a material bal-
ance around the TFE.
RESULTS AND DISCUSSION
The feed rate and temperature of the
TFE were varied over its normal range with
no observed operational problems when
operated at atmospheric pressure with the
tested sludges. There were difficulties
when it was operated under vacuum at 320
*C, as some carryover of feed into the
condensate was observed. The condensate
from the vacuum runs was a milky-white
emulsion, which would require additional
treatment to separate the oils.
When the TFE was operated at the 150
*C, some of the water in the feed was
evaporated along with most of the VO. As
illustrated in Table 2, the VO removals
ranged between 99.5 and 99.8 percent at
the low feed rate and decreased slightly
when the feed rate was increased (98.6 to
99.8 percent at a feed rate of 154 Ib/h).
The bottoms temperatures for these runs
were 98 to 102 *C, indicating that water
was still boiling from the bottoms as it
exited the base of the TFE.
The removal efficiency for volatiles
was greater when the TFE was operated at
higher1temperatures. The VO removals when
the TFE was operated at 320 *C were 99.88
to 99.99 percent, with no clear trends
relative to changes in feed rate. These
runs removed essentially all of the water
and VO from the feed sludge, along with
much of the higher boiling oils. The
amount of bottoms sludge produced ranged
between 10 and 13 percent of the feed
rate, substantially reducing the amount of
material requiring disposal. This bottoms
product was a relatively viscous, high
solids content sludge, which was still
pumpable.
Several vacuum runs were performed
with the TFE. These runs produced a
milky-white emulsion as condensate, which
contrasted substantially with the cleanly
separating organic/aqueous condensate of
the atmospheric pressure runs. A high-
temperature vacuum run (320 *C) produced a
bottoms product that was only 4.3 percent
of the feed sludge. This indicates that a
two-stage process (first-stage removal of
water and volatiles at atmospheric pres-
sure, second-stage removal of heavier oils
under vacuum operation at high tempera-
ture) could be employed to reduce substan-
tially the amount of sludge material
requiring dlsposal.
Metals in the feed sludge appeared to
remain in the bottoms products. Only
minor amounts of metals were found in the
organic condensate.
The organic condensates produced dur-
ing the atmospheric pressure tests could
easily be recycled as raw products to the
refinery operation. This would reduce the
actual operating costs of the TFE while
removing organics from the wastes prior to
disposal. The aqueous condensate was
water saturated with the recovered organ-
ics and could be sent to existing waste-
water treatment facilities at refineries.
If the process is applied for the removal
of volatiles only, the aqueous condensate
could be recycled to the process feed, so
that all water would exit with the process
bottoms. (This would not be practical if
large quantities of water we-e condensed,
as in high-temperature operction) The
bottoms sludge produced by the process
could be treated by existing methods (land
treatment) or perhaps incinerated. The
-------
TABLE 2. TFE VO REMOVAL FOR SELECTED COMPOUNDS
Operating Conditions
Test
No.
5
7
8
10
Temperature
rc)
150
150
310
310
Flow
rate
(Ib/hr)
71.6
153.7
68.5
143.4
Reduction in concentrations from feed (%}a
Benzene Toluene Ethylbenzene m-Xylene
99.58 99.61 99.48 99.54
99.73 99.78 98.83 98.64
99.72 99.84 99.68 99.67
99.76 99.90 99.78 99.75
aBased on GC/MS analyses.
-------
ultimate treatment for any bottoms product
will require additional testing of pos-
sible disposal methods.
The results from this test were used
to verify a model that can be used to
predict the effectiveness of TFE treatment
on different waste sludges. Generally, a
TFE 1s modeled as a one theoretical stage
separation device. Countercurrent steam
purging is thought to improve the separa-
tion to approximately one and one half
theoretical stages. The number of
theoretical stages, together with the
partition coefficient (K) of the volatile
organic component at the TFE operating
temperatures, and the flow rates can be
used to predict the percent removal of
volatile organlcs from the sludge 1n a
treatment device. For a complete discus-
sion of the TFE model and the pilot test,
the reader is referred to Harkins, Allen,
and Northelm (1987) (1).
CONCLUSIONS
The TFE was found to have very high
removal efficiencies of VO compounds from
the waste sludges tested. In each of
three methods used to assess the reduction
of volatiles (two headspace analyses, one
analysis of VO compounds in feed and bot-
toms), the removal efficiencies for VO
compounds were greater than 99 percent.
REFERENCE
1. Harkins, S. M., C. C. Allen, and C. M.
Northeim, 1987. Pilot-Scale
Evaluation of a TnTh-Film Evaporator
for Volatile Organic Removal from Land
Treatment Sludges"! U.S. Environmental
Protection Agency, Hazardous Waste
Engineering Research Laboratory,
Alternatives Technology Division.
(Draft. Prepared by the Research
Triangle Institute under EPA Contract
No. 68-02-3253, Work Assignment 1-6.)
-------
FIELD ASSESSMENT OF STEAM STRIPPING VOLATILE ORGANICS
FROM AQUEOUS WASTE STREAMS
Marvin Branscome, Clark Allen, Scott Ha.rklns, and Keith Leese
'x Research Triangle Institute
Research Triangle Park, North Carolina
and
Dr. Benjamin L. Blaney
U.S. Environmental Protection Agency
Cincinnati, Ohio
ABSTRACT
This paper discusses the removal of volatile organics (VO) from aqueous waste streams
by steam stripping and summarizes the effectiveness of VO removal from the waste, the air
emissions from the process, and the cost of the treatment process. Tests were conducted
at two chemical plants that used continuous steam strippers to remove VO from the waste-
water. The operation at Plant H, which produces ethylene dicnloride and vinyl chloride
monomer, treated about 852 liters per minute (L/min) or 225 gallons per minute (gal/min)
of aqueous waste containing about 6 grams per liter (g/L) of VO. The operation at Plant
I, which produces one-carbon chlorinated solvents, was smaller and treated 42 L/min (11
gal/min) of aqueous waste containing about 6 g/L of VO.
The test program evaluated the removal of VO from the water, which was about 99.8 to
99.999 percent at the two plants. At Plant H, the concentration of VO in the stripper
bottoms ranged from 0.34 to 36 parts per million (ppm) with an average of 9.7 ppm. This
wide range was caused by variations in the concentration of chloroform (the major consti-
tuent in the bottoms), which was apparently related to column fouling. This stripper
processes wastewater containing about 1.4 g/L of filterable solids. At Plant I, the con-
centration of VO in the bottoms ranged from less than 0.005 to 0.13 ppm. Solids and an
organic layer are removed in decanters at Plant I prior to steam stripping to provide a
feed stream containing about 0.01 g/L of filterable solids. Emissions of VO from the
decanter and storage tank vents at Plant I were estimated as 46 megagrams per year
(Mg/yr). Significant vent rates of VO were also measured from the condensers at both
sites. The condenser vent rate at Plant H averaged about 20 Mg/yr compared to 11 Mg/yr at
Plant I. The condenser efficiency at Plant H ranged from an average of 6 percent for
vinyl chloride to 99.5 percent for ethylene dichloride. At Plant I, the condenser effi-
ciency ranged from 89 percent for chloromethane to 94 percent for chloroform.
INTRODUCTION its 1984 amendments to control air emis-
sions from hazardous waste treatment,
The EPA Office of Air Quality Planning storage, and disposal facilities (TSDFs).
and Standards (OAQPS) is currently devel- In support of this regulatory development
oping regulations under the Resource effort, EPA's Hazardous Waste Engineering
Conservation and Recovery Act (RCRA) and Research Laboratory (HWERL) is conducting
-------
field assessments of hazardous waste
treatment processes that could be used to
remove volatile organics (VO) from wastes.
Volatile organics are defined as those
organic compounds detected and quantified
by EPA procedures, which include both
purgeable and extractable compounds.
Aqueous wastes represent a high percentage
of the total volume of hazardous wastes.
These aqueous wastes are often stored,
treated, or disposed of in open area
sources, such as surface impoundments and
open wastewater treatment units, which are
sometimes aerated. Steam stripping of the
waste prior to placement in these open
units is one promising technique that may
reduce VO emissions from these sources.
APPROACH
This project focused on the use of
continuous steam strippers. There are
potential cost and cost-effectiveness
advantages of continuous stripping,
particularly for high volume aqueous
wastes. Batch processes have been evalu-
ated previously. The goals of the testing
effort included measuring the effective-
ness of the process for VO removal from
the waste, measuring any air emissions,
and assessing the cost of treatment.
Samples of the feed strew*, to the sttaf
strippers were taken for aw^jutt ta^ gas
chromatography/mass spectroscopy (Ic/MS)
to identify purgeable and extractable
organic compounds. No significant quanti-
ties of extractable organics were found at
either plant; consequently, the sampling
and analysis for each test focused on the
purgeable organic compounds that were
identified.
The sampling at tact) site was conduct-*
ed ever a 2-day p«rtod with 5
taken each day at
from each sampj
sa*>l
per's
as " -we_
samples'wTrTTo
mi 11i 1
At Plant!
heads pace .
EPA Method (SH/which is a purge-and-trap
procedure with analysis by GC/MS. The
vapor flow rate and composition from the
steam stripper's condenser system were
also measured. At Plant H, the con-
denser/decanter was vented within a closed
system to an incinerator. The system was
f*t«nrals
maintained at a pressure of 1.3 atmos-
pheres. The vapor flow rate in this
closed system was measured by a tracer gas
dilution technique. Propane was metered
into the vapor inlet to the condenser at a
known rate and the concentration of pro-
pane was measured downstream to calculate
the vapor flow rate.
Samples of the wastewater from Plant I
were screened by GC/MS to identify the
organic compounds. Because only purgeable
chlorinated compounds were found, EPA
Method 601 was used for analysis of the
samples from Plant I. At Plant I, the
vapor flow rate from the condenser system
was measured directly with a wet gas meter
because the system was vented to the
atmosphere. Vapor samples were collected
in electropollshed stainless steel canis-
ters that had been previously cleaned and
evacuated. The vapor flow rates and con-
centration measurements were used to
calculate condenser efficiency. Addition-
al liquid samples at each plant were taken
for analysis of solids content, metals,
pH, and VO in the headspace. Process data
were collected for the steam stripping
system and included flow rates and temper-
atures of the various streams entering and
leaving the stripper.
The treatment system at Plant I also
included removal of solids and any separ-
ate organic layer in decanters prior to
steam stripping. Samples were taken from
the streams entering and leaving the de-
canter for analysis of VO, solids, and
metals to assess the effectiveness of the
treatment and to determine the character-
istics of residuals. In addition, vapor
samples were taken from the headspace of
the decanter and from. the feed tank for
the steam stripper to estimate air emis-
sions.
PROCESS DESCRIPTION
to
ttrlpper at PUnt H is used
of
vinyl chloride
w
from
_ t,
4Mf eWeroform. The
characfeT*fs"tTcs of the two waste streams
are summarized in Table 1. The primary
constituents at Plant H were ethylene
dichloride (5,630 ppm) and chloroform (271
-------
ppm). A total of 12 other compounds,
mostly chlorinated organlcs, were also
detected at Plant H at average levels that
ranged from 0.3 ppm (for benzene) to 11
ppm (for I,l-d1chloroethane). At Plant I,
methylene chloride (4,490 ppm) and chloro-
form (1,270 ppm) were the major constitu-
ents. A total of four additional chlori-
nated compounds were detected at average
levels that ranged from 5.3 ppm (for
I,l,2-tr1chloroethane) to 55 ppm (for
carbon tetrachloride). Total VO at both
plants averaged about 6,000 ppm (6 g/L).
The stream stripper at Plant H used a
tray column to treat water at a rate of
about 852 L/min (225 gal/min). Solids at
this plant were not removed prior to steam
stripping and were processed through the
steam stripper at a level of 1.4 g/L for
filterable solids. Fouling of the heat
exchanger and column from the accumulation
of solids requires that this system be
backflushed or cleaned periodically. The
company prefers to process the solids
through the steam stripper rather than
install a system for solids removal.
Removal of solids prior to steam stripping
would generate a sludge that could be a
hazardous waste requiring treatment before
disposal. The vapors from the stripper
pass through a primary condenser cooled
with cooling tower water followed by a
secondary condenser cooled with refriger-
ated glycol. Noncondensibles vented from
the secondary condenser are routed to an
incinerator. The condensate, which con-
tains both an aqueous and organic phase,
is recycled to the production process.
The steam stripper at Plant I was a
packed column used to treat about 42 L/min
(11 gal/min) of wastewater. The waste-
water is treated for removal of solids and
any separate organic phase in a decanter
prior to stripping. The treatment in-
cludes pH adjustment, addition of floccu-
lant, mixing, and settling for phase
separation of each batch in the decanter
over a 24-hour period. The aqueous phase
is decanted and stored in the feed tank
prior to steam stripping. Vapors from the
steam stripper pass through a primary
condenser and a secondary condenser, both
cooled with cooling tower water. The
condensate is separated in a decanter and
the aqueous layer is returned to the
column. The heavier organic layer is
removed periodically and returned to the
production process. The two solids
decanters are also vented to the secondary
condenser. The feed storage tank is vent-
ed to the atmosphere through a conserva-
tion vent.
After steam stripping, the wastewater
from Plant H 1s sent to the wastewater
treatment process, which includes solids
removal and biological treatment. At
Plant I, no additional treatment usually
is needed (other than occasional pH ad-
justment) prior to discharge to the river.
VO REMOVAL FROM WATER
At Plant H, the removal of the major
component (ethyl ene dichloride) was gener-
ally on the order of 99.999 percent with a
feed concentration of 5,630 ppm reduced to
0.097 ppm 1n the stripper bottoms (see
Table 1). The removal of chloroform aver-
aged 99.6 percent for 6 of the 10 runs and
averaged only 92.4 percent for the other 4
runs. A feed concentration of 271 ppm
chloroform was reduced to an average in
the bottoms of 9.6 ppm with a range of
0.13 to 36 ppm. The variations in chloro-
form removal appeared to be related to
column fouling problems because the lowest
values in the stripper bottoms were found
after backflushing the steam stripper, and
the highest levels were found Before back-
flushing when the column pressure drop was
increasing. None of the other 12 volatile
compounds found in the feed at 0.3 to 11
ppm was detected in the stripper bottoms
at a detection limit of 0.01 ppm. The
percent removal for these compounds gener-
ally exceeded 99 percent. Total VO at
this plant was reduced from an average
feed concentration of about 6,000 ppm to
an average of 9.8 ppm in the effluent, or
about 99.8 percent removal of total VO.
The Mj*r cMistittwftt at Plant I
(methyl ens cbtaridti mf jrfdufifd from an
ppm to
,270 ppm to
0.006 ppm and carbon tetrachloride was
reduced from 55 ppm to <0.005 ppm. The
other chlorinated compounds present in the
feed (chloromethane, trichloroethylene,
and 1,1,2-trichloroethane) were not de-
tected in the bottoms at a detection limit
of 0.005 ppm. The total VO at this plant
was reduced from about 6,000 ppm to <0.037
ppm with about 99.999 percent removal.
-------
The removal efficiency of this steam
stripper over the 2-day test was more
consistent than that observed at Plant H.
During the first test day, the levels of
chloroform 1n the bottoms ranged from 7 to
9 ppb compared to all values <5 ppb on the
second test day. None of the volatile
compounds in the stripper bottoms exceeded
0.023 ppm for any of the samples.
CONDENSER EFFICIENCY AND AIR EMISSIONS
The condenser efficiency (Table 2) was
evaluated at both plants from the quantity
of VO entering the overhead system and the
quantity leaving with the noncondenslble
gases. The condenser system at Plant H
included two condensers in series that
used cooling tower water followed by
refrigerated glycol at 2 *C. A total of 7
of the 14 compounds detected in the feed
were also detected and quantified 1n the
vented vapors. The condenser removed 99.5
percent of the major constituent (ethylene
dichloride) and about 96 percent of the
chloroform. The removal efficiency for
compounds present in lower concentrations
was much lower. Vinyl chloride removal in
the condenser averaged only 6 percent and
indicated that this compound passed
through the condenser in the vapor phase
and was sent to the incinerator. The
average flow rate from the condenser was
3.1 L/s and the total VO from the vent was
about 20 Mg/yr (0.62 g/s). Although the
condenser removed 99.5 percent of the
ethylene dichloride from the vapor,
ethylene dichloride was the major compo-
nent of the vented vapors and comprised
about one-half of the total VO vented to
the incinerator.
The condenser system at Plant I also
included two condensers in series; how-
ever, both were cooled with cooling tower
water. Because of no significant differ-
ences in vapor phase concentrations and
temperatures from samples taken after the
two condensers, the small secondary con-
denser apparently was not removing any
additional constituents. All of the sig-
nificant condensation was provided by the
primary condenser on the steam stripper.
Vapor phase concentrations of VO after the
primary condenser were high and averaged
44 percent VO by volume in the vapor phase
or a mass concentration of 1.6 g/L at 25
*C. The vent rate was measured as 0.2
L/s. The condenser removed about 90
percent of the major constituent
(methylene chloride) and about 94 percent
of the chloroform from the vapors. The
overall removal efficiency for total VO
was approximately 91 percent. Emissions
from the secondary condenser vent due to
steam stripping were measured as 11 Mg/yr
(0.34 g/s).
The vapor space 1n the solids decanter
contained primarily methylene chloride (28
to 32 volume percent), chloroform (6.4 to
7.6 percent), carbon tetrachloride (1.5 to
3.8 percent), and chloromethane (0.6 to
1.0 percent). The vapor space in the feed
tank also contained methylene chloride
(9.7 to 12 percent), chloroform (2.5 to
3.1 percent), carbon tetrachloride (0.7 to
0.8 percent), and chloromethane (0.2 per-
cent). Emissions from these two tanks
were estimated based on the measured vapor
phase concentrations and the working
losses from the tanks based on a water
transfer rate of 11 gal/min. Total VO
emissions from the solids decanter were
estimated as 35 Mg/yr or 1.7 grams per
liter (g/L) of water treated. Total VO
emissions from the feed tank were esti-
mated as 11 Mg/yr or 0.5 g/L treated. The
total VO emissions from the three major
sources (condenser vent, solids decanter
vent, and feed tank vent) were estimated
as 57 Mg/yr or about 2.7 g/L treated. The
estimate of annual emissions is based on
an average water treatment rate of 11
gal/min for 50 weeks during s. year.
Samples taken from the solids decanter
showed that the treatment process could
reduce filterable sol Ids from 1,100 ppm to
50 ppm. Samples from the storage tank,
which represented water decanted before
our test, showed filterable solids levels
of 11 ppm. Reductions in chromium, cop-
per, nickel, lead, and zinc were also
observed after treatment. Solids removal
prior to steam stripping decreases column
cleaning requirements and probably
improves the consistency of the operation.
However, the process generates about
190,000 L/yr of sludge, which contains the
chlorinated compounds at levels of 20 to
30 percent. The solids removal process
also increases the capital and operating
cost of the treatment system. However,
the bottoms from the steam stripper at
this plant do not require any additional
wastewater treatment (other than occasion-
al pH adjustment) before discharge.
-------
COST
Cost data were not available for the
small steam stripper at Plant I. However,
cost data were available for the steam
stripper at Plant H and for a similar
operation at Plant K, which treated a
wastewater stream similar to that at Plant
H. The steam stripper at Plant K was not
evaluated in a full-scale test; however,
process data, cost data, and samples were
obtained during a one-day plant visit.
The basic process equipment for the
steam stripping operation at Plant H
includes a feed storage and surge tank,
heat exchanger, the column and trays, two
condensers 1n series, a decanter, 8 pumps,
instrumentation, piping, and Insulation.
The total installed capital cost was esti-
mated as $950,000 (1986 dollars). The
major annual operating cost components
include utilities (primarily steam),
operating and maintenance labor, and
laboratory support for analyses. A credit
is included for the recovery of ethylene
dlchloride that is recycled to the produc-
tion process. The annual operating cost
was estimated as $250,000/yr. The total
annualized cost, which includes capital
recovery based on an interest rate of 10
percent and a lifetime of 10 years, was
estimated as $405,000/yr or $0.89/1,000 L
treated.
The data from the steam stripper at
Plant H are compared in Table 3 with data
obtained from a similar stripper at Plant
K during a one-day plant visit. One dif-
ference between the two types 1s that the
stripper at Plant H used trays for vapor/
liquid contact whereas the Plant K opera-
tion uses a packed column. The basic feed
constituents are similar; however, Plant K
has a higher concentration of 1,2-di-
chloroethane in the feed. The difference
in annual operating cost 1s probably
attributable to the higher rate of steam
usage at Plant K where approximately 75
percent of the annual operating cost is
for steam. Both of these steam strippers
achieve similar effluent (or bottoms)
concentrations of VO in the range of 1 to
2 ppm. Although the steam usage for Plant
K appears to be higher than that at Plant
H, the steam rates in terms of VO removed
are very similar (6.2 and 6.7 kg steam/kg
VO removed). The small difference in cost
effectiveness is probably not significant
and can likely be attributed to the higher
feed concentrations observed at Plant K.
Steam usage contributes significantly
to the annual operating cost of a steam
stripper. The steam usage at Plants I and
K averaged about 0.1 kg/kg water treated
compared to 0.036 kg/kg treated for Plant
H. (Each of these plants used heat ex-
changers to preheat the stripper feed with
the hot bottoms stream from the steam
stripper.) These values compare favorably
with some published design information on
steam usage. Typical values of 0.07 to
0.24 (1), 0.1 to 0.3 (3), and 0.31 (2) kg
steam/kg water treated have been reported.
CONCLUSIONS
Steam stripping can remove 99.8 to
over 99.999 percent of the purgeable
organic compounds found in the two waste
streams. The presence of solids in the
wastewater can lead to fouling problems
and variations in performance; however,
wastewater containing 1.4 g/L of filter-
able solids can be processed 1n a tray
column steam stripper. When the condenser
and tanks are vented to the atmosphere,
emissions of 20 to 57 Mg/yr can result.
The cost effectiveness of stripping a
saturated wastewater stream in systems
designed for 680 to 820 L/min was on the
order of $120 to $220/Mg VO removed. The
water treatment cost ranged from $0.89 to
$1.57 per Mg or $3.38 to $5.96 per 1,000
gallons of water.
REFERENCES
1. Ehrenfeld, J., and J. Bass. Handbook
for Evaluatino Remedial Action
Technology Plans.EPA 600/2-87-076.
August 1983.
2. Nathan, M. F. Choosing a Process for
Chloride Removal"! Chemical
Engineering. January 1978. p. 93-
100.
3. Shukla, H. M., et al. Process Design
Manual for Stripping of Organics. EPA
600/2-84-139.August 1984.
-------
TABLE 1. SUMMARY OF AVERAGE STRIPPER FEED (IN) AND BOTTOMS (OUT)
CONCENTRATIONS (ppm)a
Constituent
Ethylene dichlorlde
Chloroform
Benzene
Carbon tetrachloride
Chlorobenzene
l,l-D1chloroethane
1,1-Dichloroethene
1,2-Dichloroethene
Methylene chloride
Tetrachloroethene
1,1, 2-Tri chl oroethane
Trichloroethene
Vinyl chloride
Total
Plant H
In
5,630
271
0.27
1.7
0.38
11
4.7
8.9
1.2
1.4
7.5
4.8
8.4
5,950
Out
0.097
9.6
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<9.8
Filterable solids (g/L)
1.4
0.93
Plant I
Constituent
Methylene chloride
Chloroform
Carbon tetrachloride
Chloromethane
Trichloroethylene
1,1, 2-Tri chl oroethane
Total
Filterable solids (g/L)
In
4,490
1,270
55
33
5.6
5.3
5,860
0.011
Out
0.011
0.006
<0.005
<0.005
<0.005
<0.005
<0.037
0.009
^Averages of 10 samples taken over a 2-day test.
-------
TABLE 2. SUMMARY OF AVERAGE CONDENSER VENT RATES AND EFFICIENCIES
Plant H
Constituent
Vinyl chloride
Chloroethane
1, 1-Dichloroethene
1,1-Dichloroethane
1,2-Dichloroethene
Chloroform
Ethylene dichloride
Condenser
loading
(g/s)
0.089
0.081
0.036
0.11
0.006
2.9
63
Vent rate
(g/s)
0.084
0.043
0.031
0.013
0.001
0.11
0.34
Condenser
efficiency
(percent)
6
47
15
88
84
96
99.5
Total
66
0.62
99
Plant I
Constituent
Chloromethane
Methylene chloride
Chloroform
Carbon tetrachlorlde
Total
Condenser
loading
(g/s)
0.021
2.9
0.81
0.038
3.8
Vent rate
(g/s)
0.0024
0.29
0.045
0.0039
0.34
Condenser
efficiency
(percent)
89
90
94
90
91
-------
TABLE 3. COST COMPARISON
Item
Capital cost ($)
Operating cost ($/yr)
Total annuallzed cost ($/yr)a
Average feed rate (L/min)
Steam rate (kg/h)
Feed constituents (ppm)
1,2-Dichloroethane
Chloroform
Other VO
Bottoms constituents (ppm)
1,2-Dichloroethane
Chloroform
Other VO
Steam usaoe
kg/kg water
kg/ kg VO removed
Cost-effectiveness
$/Mg VO removed
$71,000 L treatedf
Plant H
950,000
250,000
405,000
820
1,790
5,600
270
59
0.16
0.8C
<0.01
0.036
6.2
220d
0.89
Plant K
700,000
450,000
564,000
680
4,090
15,000^
17h
31°
.037°
1.3&
1.4*>
0.10
6.7
120e
1.57
aBased on a 10-year lifetime at 10% (Capital recovery factor = 0.163).
bBased on a single sample analysis from presurvey trip.
cBased on 6 of 10 runs.
dBased on 1,820 Mg/yr recovered.
Estimated from single analysis and 329 days/year operation.
^Also equals $/Mg treated.
-------
To
Wastcwater
Treatment
Miscellaneous
Plant I
Wastcwater
1
CT^
~~^»
Feed
Tank
**
Heat
i
__**
r
i
S? iRnttnmt)
;
Exchanger
i
Overhead
Vapors
1 L -^
Steam
Stripper
^-
!
[
Cooling Tower Refrigerated S4 (Vaporj)
Water Condenser Glycol Condenser
1
"s Condensate Decanter
'
1 Vent
' r ^-- ^*^""^
n \
1 Decanter I
S3 (Condensate)
-^ Steam .
' Condensate Recycled
Bottoms
Figure 1. Schematic of steam stripper and sampling locations for Plant H. (S = sampling point).
-------
S1
Water
In
S9(V)
Vent
Condenser
-S12(V)
Vent
Solids and
Organics Decanter
S3
S2
1
Sludge
Decanted
Water
I
S4
Organics
S10(V)
I
Storage and
Feed Tank
S5 (Feed)
I
S8(V)
I
Vent
1
Condenser
Decanter
Vapors
Steam
Stripper
S6 (Bottoms)
Steam
Water
Holding
Tank
Surge Tank
Diicharga to River
Condensate
- S7
S11 (V)
Collection
Tank
Figure 2. Simplified schematic of sampling points for Plant I.
(S = sampling point, V = vapor sample)
------- |