Draft Report on Waste Pofiles
       of the Paper Industry
ENVIRONMENTAL PROTECTION AGENCY • WATER QUALITY OFFICE

-------
       DRAFT REPORT ON

       WASTE PROFILES

           OF THE

       PAPER INDUSTRY
             by

        WAPORA, Inc.
    1725 DeSales St., N.W.
      Washington, D. C.
           for the

   Office of Water Quality

Environmental Protection Agency


          Covering
    Contract #68-01-0012
    Contract #68-01-0022
     Date:  March 5, 1971

-------
                        CONTENTS
                                      PAGE
 INTRODUCTION 	1

 MAJOR_PROCESS CATEGORIES

   I.  Wood Preparation	-	5

  II.  Groundwood Pulp 	16

 III.  NSSC Pulping	22

  IV.  Kraft and Soda Pulping	27

   v.  Pre-Hydrolysis	.31

  VI.  Kraft-Sulfit* Bleaching	32

VIII.  Kraf t-Sulf ite Bleaching	32

 VII.  Acid Sulfite Pulping	35

  IX.  Deinked Pulp 	39

   X.  Paper Making	43

  XI.  Waste Paperboard	49

 XII.  Building Products 	56

 OTHER MILL EFFLUENTS	60

 WASTE PARAMETERS (SWRL)	61

-------
                               LIST OF FIGURES
                                                            PAGE


   I.  Settling Rate of Barker Screening Effluent	..-13

  II.  Wet Debarking Flow Diagram 	14

 III.  Groundwood Pulp Flow Diagram 	20

  IV.  Refiner Groundwood Pulp Flow Diagram 	21

   V.  BOD Load of Effluents from NSSC Pulping	 24

  VI.  Suspended Solids Loss from NSSC Pulping	 25

 VII.  NSSC Pulp Mill Flow Diagram	 26

VIII.  Kraft Pulping Flow Diagram 	 29

  IX.  Kraft Recovery System Flow Diagram 	 30

   X.  Four Stage Bleaching Flow Diagram	34

  XI.  Acid Sulf ite Pulping Flow Diagram	37

 XII.  Magnesium Base Sulfite Recovery System Flow Diagram...38

XIII.  Deinking of Waste Paper Flow Diagram	41

 XIV-  Fordrinier Paper Machine Flow Diagram	45

  XV.  Waste Paper Board Mill Flow Diagram	54

 XVI.  Insulating Board, Builing Board and Hardboard Flow
       Sheet	 58

-------
                    LIST OF TABLES


                                            PAGE

  I.   Major Manufacturing Categories 	  A

 II.   Leachate From Logs 	 11

III.   Analysis of Debarking Effluents	12

 IV.   Effluent Characteristics of
      Groundwood Pulp Mills	19

  V.   Analysis of Waste Paperboard
      Mill Effluents  	53

 VI.   SRWL Data for Major Industrial
      Categories 	76

-------
                             ABSTRACT







     This report  includes short descriptions of the major waste waters




discharged from pulp and paper mills previous to any external treatment.




Tte concentration values for BOD^ and suspended solids are included together




with other effluent characteristics.  A flow sheet of each major process




is also included together with references as to where the information was




obtained.




     Data collected also includes load factors  for individual manufacturing




processes with ranges of BOD  and total suspended solids lost from each,




together with corresponding typical values.  With the exception of processes




for which fiber or cooking liquor recovery processes are operative, little




can be done about these losses since they represent materials that must




be removed from the raw material in order to make a satisfactory product.




The quality and quantity of these is determined by the various raw  materials.




used such as wood, waste paper, etc.  The values set forth are referred to




as the "Standard Raw Waste Load" (SRWL).




     In addition, Tables indicate pH range, color and COD values for the




various wastes where these are available and indications as to what




heavy metals, if any, might be present.  Also, notations regarding their




potential toxicity to aquatic life are included together with a listing




of their pollutional characteristics.




     In arriving at the SRWL figures experienced judgment of both the authors




and specialists from the industy were employed to evaluate collected data.




Frequently, due to combined sewering many of the industrial figures collected




represented more than one operation and could not be used per se.  It




is felt that the data presented represent as sound values as can be  obtained

-------
considering the many variables involved in pulp and paper manufacturing.




We believe that with only minor adjustments the data will meet with




approval of those industrial engineers acquainted  with effluent control.




     The parameters of pollution as they apply to  these spent   process




waters are discussed in detail.  The limited  amount of mass  data available




in some process categories is evidence of the unimportance of  many  of  them




to these wastes.  The major problems involved with them are  caused  by  suspended




and dissolved organic matter.  Strong emphasis is,  therefore,  put upon




these criteria by tne industry and  regulating agencies.
                                 11

-------
                              INTRODUCTION






     This progress report covers the pertinent information requested by




the Environmental Protection Agency for review prior to the interim report




and conference scheduled for April, 1971.  The report includes:




     1.  A description of the processes used in producing




         most of the pulp and paper products manufactured




         in the United States.  These processes have been




         broken down into categories and sub-categories




         based on logical sequence in production and technical




         judgment on the types of wastes produced.




     2.  Narrative information on the pertinent waste load constituents




         as they apply to each manufacturing process category.  This




         discussion covers the basis for establishing Standard Raw Waste




         Load parameters.




     3.  Flow diagrams of the processes involved in each major




         category.  The diagrams show product lines, water flow,




         wastewater flow, recirculation patterns and sources of




         air pollution and solid wastes produced.




     4.  A comprehensive Table showing the "Standard Raw Waste




         Loads" (SRWL) for the processes described.  Included




         are the major parameters of concern in wasteloads from




         each process, the range of quantities of these (in mg/1




         per ton of product) and a typical level of wastes which




         might be expected.

-------
      The number  of mills  included in some of the sampling is not as large




 as  desirable  because  either the sewer division in many mills did not allow




 process effluent segregation or that surveys available did not concern




 themselves with  more  than overall discharge from individual mills or




 segments thereof.  There  is a feeling among many regulatory agencies




 that their concern is for the total discharge rather than individual




 process effluents and the data available reflects this.




      The delay involved between requests and receipt of information




 has also been a  limiting  factor.  Hence, it is felt that further information




 will be available relative to SRWL.  However, it is doubtful that the figures




 presented herein will be  substantially changed since both experience and




 published summaries strongly support the data presented.  Also abundant




 information was  available for the major chemical pulping processes which




 account for a very large  percentage of the total production involving




 the large units  of the industry.




      No information was available on a few minor processes.   A continued




 effort will be made to obtain data regarding them even though they represent




 only a small  factor in respect to the number of operating mills and tonnage




 of  product.




      More serious is  the  limited number of parameters of pollution reported.




Inmost cases, this is limited to BOD and total suspended solids.  However,




 pH,  COD and color figures are to be found in operating and research reports




which will allow  an estimate to be made.




      Little information is to be found on heavy metals or on the effect of




wastes on aquatic productivity,  however, those wastes which are potentially




 toxic to aquatic organisms are well established.   Wastes so involved

-------
are identified in the Table presented together with a statement  relative




to the undesirable qualities of each effluent.




     It is not possible to supply detailed data of value for  speciality




paper mills because of the very wide variety of products made by most




of them.  A large number of mills manufacture products on a short  run




basis.




     In considering raw waste loads it must be appreciated that  except




where initial recovery systems are involved, little can be done  to




control the volume and character of the waste waters discharged.   It




must also be realized that most mills operate with some degree of




flexibility relative to the products manufactured.  This flexibility




is reflected in effluent character, strength and volume.  Recovery systems




tend to minimize effluent variations from pulp mills.

-------
                                       TABLE I
                       MAJOR MANUFACTURING CATEGORIES OF THE




                              PULP AND PAPER INDUSTRY
  I.  WOOD PREPARATION




      A.  Hydraulic Barking




      B.  Drum Barking




      C.  Wood Washing




 II.  GHOUNDWOOD PULP




      A.  Stone Grcundwood




      B.  Refiner Groundwood




      C.  Cold Soda Pulp




III.  NEUTRAL SULFITE SECT-CH3iMICAL PULP




      A.  No Recovery



      B.  With Recovery




 IV.  KRAFT AND SODA PULPING




  V.  PRE-HYDROLYSIS




 VI.  KRAFT BLEACHING




      A.  Semi Bleach




      B.  High Bleach




      C.  Dissolving Grades (Soft Wood)




      D.  Dissolving Grades (Hardwood)




VII.  ACID SULFITE PULPING




      A.  No Recovery




      B.  MgO Recovery




      C.  NHo Recovery
VIII.  SULPHITE PULP BLEACHING




       A.  Paper Grade




       B.  Dissolving Grade




  IX.  DEINKED PULP




       A.  Magazine and Ledger




       B.  News




   X.  PAPER MAKING




       A.  Coarse Paper




       B.  Fine Paper




       C.  Book Paper




       D.  Tissue Paper




       E.  Specialties




  XI.  WASTE PAPERBOARD




 XII.  BUILDING PRODUCTS




       A.  Building Papers




       B._ Felts




       C.  Insulating Board




       D.  Hard"boaM




       E.  Exploded

-------
CATEGORY I
                          WOOD PREPARATION

Underwater Log Storage
     Some mills store their wood supply underwater, others spray log piles
with water to prevent deterioration and maintain a uniform moisture content.
The latter practice has taken precedence over the former because of its
much lower cost.  The leaching effects of underwater storage were studied
by  (Schaumburg) (12).  In his experiments (unbarked and barked) logs
were submerged for 7 days in water containing sufficient mercuric chloride
to prevent biodegradation of the leached substances.  Data obtained for
three species of wood is shown in TABLE II»giving the BOD,- values of the
water containing the leachings and the BOD^ leached from each square
foot of log surface exposed.  From these data it was computed that a cord
of unbarked wood will add from 0.5 to 7.0 pounds of BOD and 0.8 to 23
pounds of COD to the water in which it is stored.
Log Washing
     Logs are frequently washed before debarking by a water shower to
remove silt.  This practice applies to both wet and dry barking.  In most
installations the shower water discharge is activated by the log on the
conveyer so that a minimum of water is used.  The actual quantity dis-
charged per unit of wood handled or pulp produced is most difficult to
ascertain because of the wide variation in stick size relative to weight
and the fact that at all installations all the wood debarked is not pulped,
a portion going to lumber.
     It is established that this effluent is very low in volume, color
and BOD and that its suspended solids content is largely silt.  Hence,
it is generally disposed of on the land together with grits from the

-------
pulp mill or ashes from the boiler plants in dry barking establishments




or  combined with the general discharge in the case of wet barking installations.




Debarking




     Most of the pulpwood used in the United States is small in diameter




and it  is debarked dry.  However, when large diameter wood is used?wet




debarking is employed.  These latter operations are pretty much limited




to  the  Northeast and Northwest.  Wet barking of logs is generally accom-




plished by one of three methods namely, by drums, pocket barkers or




hydraulic barkers as described in Volume I of the Joint Textbook of the




Paper Mills (1).  Slabs are generally handled by hydraulic units as is




the larger diameter/round wood. The wet drum barker consists of a slotted




drum equipped with internal staves which knock the bark from the wood




as  the  drum rotates in a pool of water.  The bark falls through the slots




and is  removed with the overflow of water.  Water is recycled in some units




which debark from 7 to 45 cords daily.   Performance of these devices vary




widely  with wood size.




     Wet pocket barkers are stationary machines which abrade bark from




timber  by jostling and gradually rotating a confined "wood stack against




an  endless chainbelt equipped with "dogs" which raise the pile allowing




bark to pass between the chains.   Water is sprayed through appatures ••




in  the  side of the pocket at rates of  between 330 and 600 gpm for pockets




of  2.8  and 5.7  cords  respectively.




     Hydraulic  barkers employ high pressure water jets to blow the bark




from the timber which is either conveyed  past them or indexed under a




moving jet which traverses  the log.

-------
     Water discharged from all three types is generally combined with




prewash water from sprays, which give the logs a preparatory cleaning




and coarse screening to remove the large pieces of bark and splinters




which are conveyed away continuously.  The flowage then passes to fine




screens of the drum or horizontal vibrating type having mesh or perforated




plates with openings in the range of 0.05 to 0.10 inches.  Screenings




are conveyed away and mixed with the coarse materials, the mixture being




dewatered in a press prior to burning in the bark boiler.  Press water,




(which is combined with the fine screen effluent is minor in volume).




This waste amounts to about 300 gallon a ton and carries less than one




pound of BOD and three pounds of suspended solids per ton of product.




     The combined discharge contains bark fines and silt, the latter




varying greatly in quantity since its presence is due mainly to soil




adhering to these logs.  In dry weather the percentage of silt in relation




to bark fines is low as is the case for logs stored in or transported




by water.  However, attachment of mud in wet weather can make this material




a substantial percentage of the total suspended matter passing the fine




screens.




     Analyses of fine screen effluent following hydraulic barkers has been




given by several investigators (2)  (3)  (4)  (5)  and examples are shown




in TABLE III.In the case of this effluent the water originally employed is




all fresh process water since the close clearances of the high pressure




pumping systems supplying water to the jets will not tolerate the presence




of suspended solids in the water.  It can be concluded from these data




that these effluents have a total suspended solids content of from




521 to 2350 mg/1  with an ash content ranging from 11 to 27%, usually

-------
running below 15% for clean logs.  BOD5 values range between 56 and 250




mg/1.   These low values are due to the fact that the contact of the water




with the bark is short and no grinding action  on the wood takes place.




Hence,leaching of wood and bark solubles are minimized.   This is not




the case with drum and pocket grinding where attrition in contact with




water over an appreciable period of time takes place.  Also, spent pulping




and bleaching process waters already high in BOD are not infrequently




used for barking which raises further the ultimate level of organics




in the screened effluent.  While wet drum and pocket barker screens




discharges are not greatly different from that of hydraulic barkers in




suspended solids content, the BOD,- ranged from 480 to 987 mg/I    (6)  (7 )




in the data shown in TABLE  III.




     BOD values are also greatly affected by the species of wood debarked




and the season in which the wood was cut since the wood  juices and trash




extractables are responsible for it.  That contributed by the suspended




matter present is a minor fraction of the total BOD curves (3)  indicate




the 15 day values to be about twice that of the five day with little




further demand being exerted after this period.   The oxygen demand




rate over five days is similar to that of sanitary sewage.




     Settling will remove from 70 to  90 percmt of the total suspended




solids present and is essentially complete in 30 to 60 minutes.   Settling




curves were published by Draper and Mercier (2 )  and Blosser G )  and a




typical one is presented in Figure j .   Because of the good settling




characteristics of the screened effluent sedimentation is employed for




clarifying it.   Also, because of this attribute coagulants are not needed (8)

-------
Settling is sometimes accomplished in alternating earth embarked basins




from which the settlings, which compact well, are dredged.  More modern




practice is the use of circular, heavy duty type clarifiers.  These




are designed for a rise rate of 1000 to 1200 gal/ft^ of suface area a




day and have a retention period of about two hours.   These are equipped




and piped to handle dense sludge such as that produced when considerable




silt is present in the  underplane as well as a skimmer to collect the




floating materials, some of which are always present,  The underflow is




removed by means of a diaphram, plunger or screw pumps and delivered




to drying beds or to a vacuum filter for dewatering.  The latter can be of




the disc or drum type, and because of the freeness of the solids this can




operate at high submergence producing a thick cake.   Drum speed is variable




so that variations in cake freeness can be accomodated and a vacuum of about




15 inches is desireable.  Filter media frequently consists of 120 mesh




stainless steel wire cloth.  Filter cake produced contains about 30% solids




and loadings range from 10 to 12 pounds of dry solids per square feet




per hour.  Such cakes are either disposed of on the land or sold  as mulch.




A diagram of the entire process is presented in Figure II




     Effluents from clarifiers are not treated furtner separately but combine




with pulp mill and other wastes when biological treatment of them is practiced,




As can be judged from the BOD rate biological treatment of them represent




no problems.




     Pennsylvania established raw waste standards for barker effluents




in the early 1950's (9).  These allowed 50 to 70 pounds of total suspended




solids and 15 to 20 pounds of BODc per ton of pulp produced.  Raw waste




standards for barker effluents are of little significance since no control

-------
can be exercised over the process discharge except to see that screening




and clarification are adequate.   The state of Washington, however, has set




an effluent standards of less than 200 mg/1  of volatile suspended matter,




a value which can be met by clarification installations  of good design and




operation.  It is impossible because of the many variables involved to set




a fixed number for the volume, pounds of BOD^ and  total  suspended  solids




discharged per ton of pulp produced.   However,  a single  barker  of  the




usual size operating on common sizes  of logs can generally serve a 200




to 300 ton/day pulping operation  and  employs between  100 and 150




gpm of water.
                                 10

-------
                                                  TABLE II
LEACHATE FROM LOGS OF DIFFERENT SPECIES - (7 DAYS EXPOSURE)
                                          BOD
(WATER TREATED TO PREVENT
     BIO-DEGRADATION)

        COD         „
Douglas Fir
50 years old
Douglas Fir

Douglas Fir
120 years old
Hemlock

Pondorosa
Pine

Bark
No Bark
Bark
No Bark
Bark-
No Bark
Bark
No Bark

Bark
No Bark
54
34
84
120
6
42
15
. 79

42
92
0.9 .
0.9
1.3
1.2
0.1
0.6
0.3
0.9

0.8
1.4
193
287
272
313
53
142
101
174

284
185
3.2
3.2
3.9
3.4
1.0
1.9
0.15
0.45

4.2
2.8

-------
            TABLE III




ANALYSIS OF DEBARKING EFFLUENTS
Mill
I
2
3
4
5
6
7
8

9
10
11
Type
Debarking
Hydraulic
IF
II
(1
1 1
M
fl
ft

Drum
Drum
Drum
SSttSa
— — —
««_
^« M
...

	
(Avg)
	

	
	
	
Tot al ,
Suspend
Solids
2362
889
1391
550
521
2017
2000
600

2017
3171
2875
Non-
gSIids
141
101
180
66
53
69
<200
41

69
57
80
p/c Ash
of S.S.
27
14
17
11
13
21
19
10

	
21
18
BOD
85
101
64
99
121
56
97
250

480
605
987
Color
MM/1
<£50

-------
                                    FIGURE  I

                                   SETTLING RATE OF

                               BARKER SCREENING EFFLUENT
EH
U
s
O
w
Q
§
^
P?
Pn
W
CQ
    100
     90
     80
70
     60
     50
       imri±a<«CTco]jr^UMMi
                                                           80          100
                  3240
                          1620
                                            1000
                                                     810
                                                                       648
                       CLARIFIER SURBACE  LOADING- Gal./Ft./Day
                                        13

-------
                                                   FIGURE II
Water
Raw
Logs
[-
Log Wash
•<>
                         Deck
                         Drain
                                       West Barker
                                       Drum Packet
                                    or Hydraulic .Type
                                                            Logs

                                      Coarse
                                      Screening
                                                      ...
                                                      A
Off
Gas
                                                                     3yclon«
                                            ,           '  Press     I

                   r~Fmra;rRe-t"rn-^        VTSTrT           ^	j

                                    r  Fine           I  •
                                      Screening                             Bark
                                      	1	'                     Boiler
                                            i


Filter                              I  ~~ Bark
Cake             Vacuum    Underflow  Clarifier       I   Overflow     To Mill
poll     *»-.    Filter  P1|                 [           "*"  Treatment Plant
jConditioner



Product   	
Bark      ....
Water     >  _
Gas       __ .
                                                                                      Bark
                                                                                      Ash
                                                                                           Wet Debarking
                                                                                           Flow Diagram

-------
                                REFERENCES
                             WOOD PREPARATION
  1.   "The Pulping of  Wood,"  Textbook Committee  of  the Paper  Industry,
      2nd  Edition, Volume I,  McGraw Hill Book Company, New York  (1969).

  2.   Draper,  R.  E., and  Mercier,  F.S.,  "Hydraulic  Barker Effluent Clarifier
      at Wood  Products Division,"  Weyerhaeuser Company, Everett, Washington.

  3.   Blosser,  R.O., "Practice in  Handling  Barker Effluents in Mills  in
      the  United  States", NCASI Technical Bulletin, No. 194   (1966).

 k.   "Pollutional Effects of Pulp  and Paper Mill Pastes in Puget Sound,"
      U.S. Dept.  of Interior, FWPCA, Portland, Oregon, Washingtci State
      Pollution Control Commission,  Glympia, Washington (l-larch. 1967).

 5.  Rudolfs,  W.  , "Industrial Wastes," Chapter #10, ACS Monograph #118
      (1953).
 6.  New Zealand Forest Products,Ltd., Private Communications.

 7.  Vickerman, J. L., NCASI Technical Bulletin,  Purdue University,
     Lafayette, Indiana.

 8.  Klingner, K., "Clarifying Debarker Waste Waters through Flocculation,'
     Zellstoff Papier (German), 13, No. 181  (1964).

 9.  Pennsylvania State Department of Health, "Raw Waste Standards for  the
     Pulp and Paper Industry"(1951).

10.  Washington State Standards for Barking Effluents.

11.  Graham J., and Schaumburg,  F.D., "Pollutants Bleached from Selected
     Species of Wood in Log Strange Waters," 24th Industrial Wastes  Con-
     ference, Purdue University, Lafayette, Indiana (1968).

12.  Schaumburg,, F.D., "The Influences of Log Handling  on Water Quality,"
     Department of Civil Engineering, Oregon State University,  Project
     No. 2, FWPCA Regular Grant, #WP-013220 (1969-1970).
                                   15

-------
CATEGORY II




                         GROUNDWOOD PULP MILLS




     Groundwood is produced from roundwood by pressing logs against a




large grindstone hydraulically in machines designed for this purpose.




The logs are barked prior to grinding, hence groundwood mills generally




have a wood preparation plant similar to that of chemical pulp mills.




On discharge from the grinder the pulp is screened free of splinters




and other coarse wood debris then thickened on deckers.  The decker




filtrate is generally recirculated with some being bled off continuously




to prevent solubles from building up in the system with attending slime




problems.  This discharge seldom exceeds 10,000 gal/ton of product and




in some cases is as low as 2000 gal/ton.  The BOD5 of these wastes ranges




from about 5 to 20 ppm and is due largely to wood juices.   Hence,




the species of wood and the season at which it was cut influences this




number and nothing can be done in the manufacturing process to control it.




Total suspended solids content is quite uniform at mills exercising good




loss control, running from 10 to 20 pounds per ton.  In the case of large




mills this is frequently on the lower sides.




     A list of mills showing their effluent volume together with their




BOD^ and total suspended solid losses is shown in TABLE IV the U.S.




Forest Products Laboratory, and others, give similar numbers.




     The only raw waste standards of record for mills of this type are




those set forth by Pennsylvania.   These set forth an effluent flow range




of 5 to 10 thousand gallons per ton of product with a BOD5 loss of 16




to 22 pounds per ton of products  and a suspended solids loss of 70 to 35 .




The latter figures were based on  older practice in which decker seal pit




water was not  recirculated.





                                  16

-------
     Groundwood pulp is also produced from chips by passing through disc




refiners.  Two  stages of refining are employed followed by a third




generally a part of the papermaking process.  These machines consist of




fixed and rotating serrated discs,;  between which chips or saw mill residues




are passed.  Some machines employ discs turning in opposite directions.




Water is added with the chips and the pulp is discharged as a thick slurry.




     In the case of both  stone and refiner groundwood, the pulp is diluted,




screened and then deckered to the desired consistency.  The discharge




from the process is water lost from the deckering system, the remainder




being returned for stock dilution. Figure III and IV show flow designs.




     Groundwood pulping effluents can be clarified by settling of flotation




yielding a clear effluent since about 90% of the total suspended solids




are settleable.  However, the sludg'e produced is very hydrous averaging




only about 0.5%   consistency and most resistant to dewatering.  It can




be dewatered by the addition of other pulp and paper mill solids if a sufficient




percentage of them are available.  These are generally supplied by settling




two wastes together.




     Groundwood mill effluent is responsive to biological treatment alone




and in combination with other wastes such as kraft pulping and bleaching




effluents.  However, when treated alone by the- activated sludge process




a relatively lower oxidation rate has been observed for it than when com-




bined with kraft mill discharges.




     Two large mills treat this waste in combination with bleached kraft




effluent by the activated sludge process and two others in aerated




stabilization basins.  Another mill employs storage oxidation for like




treatment.






                                  17

-------
Bleaching of Groundwood Pulp




     Groundwood pulp is generally bleached with hydrogen or sodium




peroxide, sodium or zinc hydrosulfite and sodium sulfite.  Interest




has developed recently in the use of. peracetic acid,  sodium borohydride and




amine borides for this purpose,  but their use is not  established.




     The pH is generally adjusted to between 4.5 and  7.0 depending




upon the bleaching agent and sometimes 'complexing chemicals are added to




tie up heavy metals and other undesirable material  which may be present.




Buffers and catalytic agents are also used at times.




     Since groundwood can be bleached at  high consistency it is frequently




used without washing.  Hence, the bleaching operation itself produces no




liquid effluent, the small amount of residues appearing  in the  paper  machine




white water.
                                18

-------
                            TABLE IV
Effluent Characteristics  of Ground Wood pulp Mills
              Eff.  Floxj
              Thous . /gal/t on
      Mill


      1                  6.3

      2                  1.9

      3                  4.4

      4                  5.4

      5                  8.3

      6                  2.7

      7                  2.2


U.S Forest Prod.  Lab.

Gur nil am,'' Inc..  Was t e
V/at er Contr oi''
Chap. 20 - Genm       4 to 10

Penn. Rav; V.'aste
Standards              5 to 10
BOD^5
ft/ton
11
8
11
9
18
19
4
rrl 0 o
1,0. v.-
#/tor
16
1<
11
1?
1"
-
•,2
                                       3 to 18
                                      15 to 25    40 tO 80
                                      16  to 22     70 tO 85
                               19

-------
Product _
Water	
Screenings .,
Chemicals  	
                                    FIGURE III
Groundwood
   Pulp
Flow Diagram
                  Water
              Overflow
                                  Peeled
                                   Wood
                                    Storage

                              •C»4  Grinders
                                      I
                                  Course
                                    Screens   f
                                                  Screenings
                                                             Water
                                              Product
                                       20

-------
                                        FIGURE IV
Product
Water
Refiner Groundwood
     Pulp
  Flow Diagram
       Return
       Fiber
           Water
     ProducUo
                                                                  Overflow
                                                                    to
                                                                   Sewer
                                         21

-------
  CATEGORY III




                            NEUTRAL SULFITE




                         SEMI-CHEMICAL PULPING
      Approximately 10,000 tons of NSSC pulp is produced in the United




 States daily.  This is a two stage process in which the wood chips are




 softened by a short cook with a neutral sodium or ammonium sulfite




 solution;  then defibrinated in a refiner.  Pulp yields from the




 wood range from 60 to 80 percent on a bone dry basis to produce a variety




 of products from corrugated'board to a bleachable pulp.  Most, however,




 goes to coarser products since the bleaching of this pulp will soon



 come to an end in this country.




      While some mills buy the -cooking chemicals,  most  prepare liquor by




 burning sulfur and  absorbing  it  in ammonia or  soda ash.   This part of




 the process produces  little  liquid wastes  'other than fioo drainings




 and equipment  wash-up  waters.




      Chips  are cooked  in  both batch and continous digesters and passed




 through refiners  prior  to washing.   Digester relief  and blow  gases are




 condensed,  and  in some mills used  for pulp washing.  Wash  water together




 with  drainings from the blow  tank  are delivered to the.recovery or




 liquor burning system.  Since many of these mills are adjunct to kraft




 pulp mills  the spent liquor is recovered in the kraft system, supplying



 the necessary chemical make-up.




     From the washers the pulp is conveyed to an agitated  chest where it is




diluted with white water from the paper mill to the desired Consistency




for feed to the secondary refiners serving the  paper making operation.  Other




than spent liquor,the  pulping and washing  operations discharge little waste




water  since the small  amount  of residual liquor solids  present in  pulp
                                  22

-------
is carried through the machine system passing out with the overflow white




water.




     Spent liquor is commonly fed to triple effect evaporators after which




it is burned with bark, in a fluidized bed or in a special furnace if chemical




recovery is practiced.  The latter practice is limited to a few large mills.




     The final effluent from NSSC pulping is low in volume because of the




high degree of recirculation practiced.  For the same season it is usually




high in BOD^ ranging from 1500 to 5000 mg/1 with a suspended solids content




of from 400 to 600 mg/1.  The color and COD content are correspondingly




high. Overall  process losses without recovery are shown in Figures "



and VI.  Figure "VTI  shows a flow diagram of  the NSSC Pulp Mill.
                                  23

-------
                            FIGURE V
   700
   600
   500
I
g
§
CO
o
Pk
   400
   300
   200
   100
                                                         BOD LOAD OF

                                                         EFFLUENTS FROM

                                                         NSSC PULPING
               BLEACHED
                 UNBLEACHED
                  1___L
        50
55
                              60
                       65
J_

 70
                                                                  75
tn&e-'Brt



  80
                         PERCENT YIELD
                                      24

-------
                                 FIGURE VI
O
ra
en
P
O
CO

P

s
55
w
^
CO
en
P
    120
    100
     80
SO
     40
     20
                                                   SUSPENDED SOLIDS LOSS


                                                         FROM

                                                       NSSC PULPING
         0
                   60
                          65
70
75
80
85
                                 PERCENT YIELD
                                       25

-------
Product    _
Water
Chemicals
Steam
       FIGURE VII
                                                             NSSC  Pulp Mill
                                                              Flow Diagram
                   Chip
                    Storage
                     Cooking
                     Liquor
                                  Digesters
                                                   1
                                                                 Cooling
                                                                 Water
                        Steam
                 Dilution
                 Liquor
                                   Blow
                                   Tank
                                  Refiners
          I
                                   Washers
          Spent Liquor
            Evaporators
                                      i
                                        i
                                       vap.
                                       onfl.
                                      Boiler
                                      Plant
                                      	1—
                                                         White
                                                         Water
                                                         Tank
                                                            t
                                                            I
                                      o-—
Overflow
   to
  Sewer
                                                         Saveall
                                  Shredder
                                   Fitter
                                     to
                                   Process
                             Paper
                             Machines

                                          Stock
                                          Gas
Liquor
 Burning
or Recovery
                                                                    Product
                                                          Water
                                                    Recovered Chemical
                                       26

-------
 CATEGORY IV
                          KRAFT AND SODA PULPING


      About 85 percent of the chemical pulp produced in the United States

 is kraft pulp.  In the kraft pulping process wood chips are cooked in

 either batch or continuous digesters with    solution of caustic soda and

 sodium sulfide.  Because of the high cost of the chemicals employed and

 other reasons,a recovery process is inherent to this pulping method.

 This necessitates separating the spent liquor from the pulp to a high

 degree and in as high a concentration as possible.

      The liquor is then evaporated in multiple effect evaporators followed

 by either a contact evaporator or a concentrator.  The heavy liquor is then

 burned for its heat value in a recovery furnace and the ash,which is

 in the form of a smelt, dissolved in water and processed to render it

 suitable as fresh cooking liquor.

      The waste water streams of greatest importance which are discharged  from

 the cooking section of the mill are digester relief and blow condensates.

 Turpentine is generally separated from these by gravity and the water

 sewered.  It contains mainly methanol, and accounts for about one-third

 of the BOD5 lost from the process.

      Spent liquor is separated from the pulp by counter-'-.urrent vacuum

or  diffuser washing and the pulp diluted for screening.  It is then

 deckered back to high consistency for refining and the water removed

 is sewered.  This accounts for another third of the BOD^ loss and

 contains some suspended solids.

      The remaing third  consists of evaporator condensates, chemical

 plant wash waters, flow and miscellaneous drains.

      Combined kraft mill effluent generally ranges between 150 and 300 mg/1


                                    27

-------
BOD,- and contains a similar, concentration of suspended solids together with




750 to 1500 mg/1 of color.   Total solids run normally from 1200 to 2000




mg/1, the inorganic portion of which consists mainly of sodium and




calcium sulfates.  The pH is between 9.0 and 10.0 under normal operating




conditions and the COD between 350 and  500 mg/1.




     This waste responds well to common treatment processes such as sedimentation




and biological oxidation when nutrients are  added.   Methods for  removing the




color and refractory organics are under large scale  mill  investigation




by the industry and Office  of Water Quality.  Mainly methanol accounts for




about 25 percent of the total BOD load  of a  mill.




   Figure VIII shows a kraft pulping flow diagram.




   Figure IX shows a kraft  recovery system flow diagram.
                                 28

-------
    Product"
    Water
    Chemicals
    Steam
                                    Kraft Pulping
                                    Flow Diagram
                                       FIGURE VIII
        Chips
        Steam
              	J" White Liquor


              	_|" Black Liquor
                                                              Condensate
                                                         	C>JTo Sewer
                 rurpentine
                 Recovery
                                                              Turpentine
                                                     Cooling
                                                              Water
                                             Accumulator  ._ _ —
           lulti Effect
            Evaporators'
 Weak Liquor
   Storage
           Blow Tank
Contact
 Evaporator
     To
Recovery
  System
               Talloil
                                                                 Non-condensable
                                                                   Gases
                                                                Fresh Water
                                                                     i
                                                                     i
                                               Washers
                                    Knotters
                                                    Rejects  «^—I
Screening
                                                                  Decker
                                    Brown
                                    Stock
                                    Storage
                                           29

-------
Product
Water
Chemicals
Steam
Kraft Recovery
   System
 Flow Diagram
                              FIGURE IX
                                                          Off
                                                        Gases

•

Strong Steam <>• •
Black
Liquor -^
-i _ _ _ ^»
Storage

Salt
Cake

t
ff Gases
i r Weal
£ Water Lm
; j— L"vdLt;i ffasj
i
i
Scrubber — - (
T.imp

Grits L- '
J0' ' _ _ ./i 	
! * *
1 '.._ _i tator
A
T
i
Recovery
Furnace
j
I" ' T j
9 *
Dissolving
Tank
1
< i
i i
^
Green
Liquor
Clarif ier
i
i i

- "7

Caus.ticizing

i
*
White
Liquor
Clarif ier
! !
i i
i
i
i
• • ^.<="-i
— - 1
i
i
i
>
i
i
i

i
i
i Salt
^ Cake
Water
i
^
Dregs
Washer

	 4

i
i
i
V
Dregs




Whi te
-._ Liquor
Storage
                                 30

-------
   CATEGORY V
                              PRE-EYDROLYSIS


     In order to obtain a more easily bleaching pulp from the kraft  and
sulfite processes, the chips are sometimes steamed in the digester prior
to addition of the cooking liquor.  After steaming the digestor is relieved
and drained.  The condensate and drainings contain wood solubles and have
a BOD5 value of from 2,000 to 5,000 mg/1.  This practice is followed
particularly in the production of dissolving grades where coupled with a
"soft" cook, "bleaching chemical consumption and bleach plant as well as
overall mill losses are reduced since more organic material goes to  the
recover plant.  The pre-hydrolysate is frequently added to the weak  black
liquor, hence does not enter the sewer system.
                                      31

-------
  CATEGORIES VI AND VIII



                          KRAFT-SULFITE BLEACHING
       The most important bleaching operations from the effluent standpoint




  are those for sulfite and kraft pulps..  This is because a considerable amount




  of organic material is separated from the pulp as compared to bleaching




  mechanical pulps and no method for its recovery is available.  Hence, no




  control of these losses can be exerted other than by  external treatment




  The inorganic constituents of the waste,  mainly chlorides,  can also prove




  a problem in receiving waters.




       While there can be many stages in a  bleach plant,  the  important




  ones from an effluent standpoint  are the  chlorination and alkaline




  extraction stages.   The finishing steps such as those involving




  hypochlorite and chlorine dioxide usually produce  a wash  water  that can




  be recycled to the  chlorination and  extraction  stages.




       Bleaching effluents are high in color,  in  particular those from the




  caustic extraction  stages in which color  bodies  chlorinated  in the first




  stage are washed from the pulp.   Color values of 6000 mg/1 are not




  uncommon in the  combined  chlorination and extraction wash waters while  BOD




  values  range from 150 to  300 mg/1 depending upon the de'gree  of recirculation




 practiced.   Chloride concentration  in the  effluent can be accurately  com-




 pited  by adding the chlorides present in the process water to  those added




 in the forms  of chlorine,  chlorine dioxide and hypochlorites  to the process.




      Degrees of bleaching vary and the sewer losses increase with  the




 brightness to which the pulp is bleached.  The bleaching  technique  is also




. used to produce dissolving grades of pulp  which consists almost entirely




 of alpha cellulose.   Since the shrinkage experienced in  producing these




 giades is Of the order of 25 percent,  as compared to 5  percent for papermakir.g
                                   32

-------
grades, sewer losses are correspondingly high.   This is particularly




the case for the oxygen demand values since considerable hydroloysis of




cellulosic material takes place.  However, when soft wood is involved more of




the load is in the prehydrolysate and cooking liquor since these woods




can be better prepared for bleaching than the hardwoods.




   Figure X shows a four stage bleachery  flow diagram.
                                   33

-------
Product
Water
Chemicals
Steam
FIGURE X
                    FOUR  STAGE BLEACHER*
                    FLOW  DIAGRAM
                                Brown
                                Stock
                                Storage
Chlorination
Stage
1
f
                                                      — Chlorine
                                            	Fresh Water
                               Caustic
                               Extraction
                      [Caustic
                    ""[Soda
      Chlorine
      Dioxide
      Fresh
      Water
       Sulfur
       Dioxide
                               Hypochloriteo—  - -
                      I  Hypochlorite
                               Bleached
                               Pulp
                               Storage
                                   34

-------
CATEGORY VII





                         ACID SULFITE PULPING




     About 10,000 tons of sulfite pulp is produced daily in the United




States.  It is produced by, cooking wood chips with a bisulfite  solution.




This was originally calcium bisulfite, but modern mills employ more soluble




bases such as magnesium, ammonia or sodium so that the liquor can be




readily burned and the chemicals recovered.




     Cooking acid is made by reacting the base with sulfur dioxide, usually




produced by burning sulfur.  The finished acid is cooled, filtered and




adjusted to strength and         for use.  Practically all the water leaving




this step in the process is cooling water which can be reused elsewhere.




The remainder comes from floor drainage, filter backwash and other




equipment cleaning operations and the impurities contained therein are in-




organic in nature.




     After cooking the pulp is blown to a tank or blow pit and the "pulp




washed either in the latter or on drum washers.  Final wash water is




sewered together with relief and blow condensates when the latter are




collected.  The combined wastes amount to about one-third the total




BODc lost from the process.




     Spent liquor  is then evaporated in multiple effect long tube




evaporators and subsequently in a contact evaporator.  Condensates from the




evaporation step are high in acetic acid and account for over 50 percent




of the BODr of the combined mill discharge.




     The liquor is burned for its fuel value in special furnaces and in




the case of magnesium and sodium the chemicals are recovered from the ash




or smelt.  Sulfur dioxide recovered from the off-gases is employed in





this recovery.
                                  35

-------
     Total effluent from sulfite mills  employing recovery range from




1000 to 2000 mg/1 BOD5 and  from 100 to  200 mg/1 in suspended solids.




COD values range from 1000  to  1500  and  the pH is acid running from 2.0




to 3.0.




     After neutralization,  sulfite  pulping effluent responds to biological




treatment for BOD reduction when nutrients are added..




   Figure XI shows an acid  sulfite  pulping flow diagram.




   Figure XII shows a tnagnesium base sulfite  recovery system flow diagram.
                                 36

-------
                                FIGURE  11
Product     ^	                     r	
Water       	                        ACID SULFITE
Chemicals      	                         PULPING
Steam	                        FLOW DIAGRAM




       Sulfur "1	cj  Sulfur
             J          Burner

       Water

       Lime   I	   -^ Absorption
       Stone S        L£^fL__
                               *

             -,        .	i
       Cooking	oUcid
             J*0	Cooler	|                       S02
                                                    Chip     To Process
                                                  Storage
                        Cooking Acid
                           Storage                                  >

                               i


                                           _A__        ]	
                                                                 e
               ->.                       ^^   ^         Relief •
       Steam   1	    Digester     ['Gases''    •    i
                  Red
                  Liquor
                  Storage
Blow Pits
  or
Washers
                To Recovery
                   or
                By-Products
    I
                                         Pulp

                                                      Blow Gas
                                                      wash
i
                                    37

-------
Product
Water
Chemicals
Steam
                                 FIGURE  12
                           Magnesium Base
                           Sulfite Recovery System
                             Flow Diagram
                               [v
 eak Red
^iquor Storagi
                                Evaporators

                                                  Condensates
                                                 	1
                               Strong Red
                               JLiquor Storagi
                            To
                           Sewer
 Fresh
 Water
Off
Gases
*
•
•
•
._ S09
"^r, ^ *& ~
Recovery ^
•
i.
fortification
Tower
f i:_ .

Sulfur
Burner <> —

Direct Contact
Evaporator
1
\

Recovery
Furnace
I
I
Dust
Collector
WgO

r-Mg
|_ Ma
- - s>
_ — Sulfur


1
O
keup ,
»
r

Acid
Filter
i 	
i
Cooking
Acid
Storage
Bac
Was
:k
3h

-------
 CATEGORY VTTT


                            PEINKING PULP





     Waste  papers  are deinked  for recovery of their fiber content mainly



 at nine  large mills  in  the United States.  Six of these deink magazine,



 ledger and  other high grade raw stocks  and three mills newsprint only.



 A large  number  of  small mills  deink a variety of waste papers on a small



 scale and frequently on an  intermittent basis. Some mills also reclaim pulp



 from  trimmings, brake  and other papers which have not been used but are



 manufacturing wastes.



     The deinking  process involves cooking the papers in an alkaline solution,



 soda ash, caustic  soda,  sodium silicate and at times sodium peroxide is



 used. Some  employ  dispersing agents as  well.  The chemicals saponify these



 ink vehicles and solubilize coating adhesives allowing the ink, coatings and



 fillers  to  be subsequently washed from  the pulp.  In the case of news print,
                                                                   *


 which consists  only  of  fiber and ink, a detergent is used to separate the



 ink so that it  can be washed out.



     Washing is accomplished on Lancaster washers, in beaters, and in the



 case of  some small operations,  on side  hill screens.  With some magazine



 stocks as much  as  40% of the bale weight of the paper is lost to the sewer



 in the washing  operation



     After  washing,  the recovered pulp  is generally given a light bleach



 with a hypochlorite.  The pulp is washed again after bleaching on drum washers



 in large mills, but  small ones usually  wash in the beaters.  Loses from this



operation are very small as compared to the others from the process, and



 since the effluent from it is  generally combined with this total flow, it



 is included in  the overall sewer loss data.
                                     39

-------
     Since the range of losses from the deinking of magazine and ledger




type stocks is so wide and newsprint so constant separate figures are presented




for each.  The ash content' of the suspended matter contained in the former




is generally and in the latter low.




     The suspended solids concentration deinking wastes from magazine




and ledger stock stocks runs from 1000 to  3100 mg/1 and the BOD in the




order of 300 to 500 mg/1.  Combustibles present in the suspended solids




range from 28 to 61 percent and the  total  solids from 1,900 to  as high




as 10,800.
   Figure 13 shows a deinking of  waste paper  flow diagram.
                                 40

-------
Product
Water
Chemicals
Steam
        Waste
        Paper
     Steam
                               FIGURE 13
                                I
                             Rifflers
                     	
                                 I
                           Centrifugal
                            Cleaners
                             Washers
                            Bleaching
                             Washer

                 Effluent
                   to
                  Sewer
                           To Process
Deinking of Waste;
    Paper
Flow Diagram
jf"*-.
v-»
I_
___

Digester



1

r
Refiner
  [cooking
  (Chemicals

  JFresh
"JWater
                                                          Bleaching
                                                          Chemicals

-------
                               REFERENCES

                              DEINKING PULP


1.  TAPPI Monograph #16, "Deinking".

2.  "Deinking Report", NCASI Technical Bulletin #5 (1946).

3.  Hodge, W.W. and Morgan, P.F.,  "Characteristic and Methods of Treatment
    of Deinking Wastes", Sewer Works Journal, p. 830 (1947).

4.  Data supplied by NCASI and mills

5.  Pulp and Paper Industries, Joint Textbooks, Vol.  Ill,  McGraw Hill Publishing
    Company (1969).

6.  Klebbe, P.J. and Rogers, C.N., "Survey of Water Utilization and Waste
    Control Practices in the Southern Pulp and Paper  Industry,"Dept. of
    Wood and Paper Science, North  Carolina State University, Raleigh, N.C.(1970).

7.  Nemerow, N., "Theories and Practices of Industrial Waste Treatment",
    Addison-Wesley Publishing Company, Reading, Massachusetts (1963).

8. Pulp and Paper Manufacturing, Volume III, McGraw Hill Publishing Company,
   New York (1970).
                                 42

-------
  CATEGORY X




            MANUFACTURE OF FI1IE PAPERS, BOOK PAPm AM) TISSUE






     Most  fine paper, took paper and tissue is manufactured on Fordrinier




machines.  The pulp  employed  is refined and cleaned with centrifugal




cleaners and the  necessary additives applied ahead of the machine. These




consist of sizing materials such as alum and rosins, sodium aluminate and




certain wax emulsions.  Synthetics such as acrylics, isocyanates,  alkene




ketene dimer, fluocarbons and others are sometimes employed to impart




special characteristics to the paper produced.  Fillers such as clays,




calcium carbonate and sulfate, talc "barium sulfate, alumina compounds




and titanium dioxide are examples of these.  When fillers are employed,




retention  aids, generally synthetic resin type compounds are added to in-




crease retention  of  the filler in the  sheet.  Fillers add opacity to the




sheet and  improve printatdlity.  They  are added in quantities up to 15$




•"by dry weights of the materials employed in the process.




     Some  papers  are machine  coated with mixtures of pigments and filler




materials  and adhesives such  as especially prepared starches, dextrines




and gums   such as mannoglactans and synthetic  resins.




     All modern mills recycle most of  the machine waters and employ a




save-all to capture  materials lost through the Fordrinier wire.  These




employ sedimentation, filtration and floation with the separated materials




being returned to the process and a portion of the clarified water re-




turned for stock  preparation  and other uses in the paper machine system.



     White water  from paper manufactured without fillers produces a machine




overflow water containing from 150 to  300 ppm of suspended matter




which consists mainly of pulp fines and is about 90% organic in nature.




EOD5 values are in the  same range, the demand "being due to the cellulose
                                    43

-------
present as veil as organic additives.



     Filled and coated sheets produce effluents of about twice the




suspended solids content of those not containing inorganic additives.



About half of the additional suspended matter consists of these sub-



stances, hence their ash content is high, frequently amounting to kO% to



50$ of the total suspended solids.  BOD values are frequently higher



"because of the adhesives used to retain the filler or coating in or on



the paper.  The inorganic materials impart a high turbidity to these



effluents which is generally in proportion to the percentage used in the



furnish.  The true color of such effluents is low and the pH is in the



neutral range.



     These machine waters respond well to treatment "by the usual pro-



cesses with the exception of the fac.t that due to the presence of very



fine, high "brightness inorganics, removal of all opalescence is



difficult.



     Tissue and toweling papers are produced on Fordrinier paper machines



from furnishes consisting mainly of bleached sulfite, kraft and ground-



vood pulp.  Rosins are sometimes added to give these products special



properties such as high wet strength.   Because of the light weights of



these sheets the volume of water employed is high and the effluents weak



ranging in total suspended solids content of from 15 to 250 -mg/1  and



BOD values of from 35 to 100 mg/1.   These run higher at a few mills



vhich use some deinked pulp in the finish.  The pH value is substan-



tially neutral and natural color is very low.




     Figure 14  shows a Fordrinier Paper Machine Flew Diagram.
                                   44

-------
            Product
            Water
            Chemicals
            Steam
                               Fordrinier Paper Machine
                               Flow Diagram
                                                        FIGURE 14
                     Pulp
                     Chest
                   Refiners
                                                	 Fresh Water
                                       Filtered
                                       White
                                       Water
                                       Tank
Save
All
Rich"
White
Water
Tank
Ui
                                                                                          Overflow
                                                                                             to
                                                                                            Sewer

-------
                             REFERENCES

           MANUFACTURE OF FINE PAPERS  AND BOOK PAPER AND TISSUES


1.  Wisconsin State Department of  Health, Pulp and Paper Advisory
    Committee Report (1965).

2.  Black,  H.H.,  "Baseline for A Normal Tissue Mill",  Division of Pure
    Waters, State of New York.

3.  State of Pennsylvania,  "Raw Waste  Standards"  (1951).

4.  NCASI Data Review.

5.  State of Ohio,  "Raw Waste Standards" (1953).

6.  Gurnham, F.,  "Industrial  Waste Water Control",  Chapter  20,  #357
    Academic Press (1965).

7.  Pulp and Paper Industrial Joint Textbook Vol.  #ni  McGraw  Mill
    Publishing Company,  New York.

8.  Private Communications  -  Scott Paper Company, Westvaco, Inc.  and
    Mead Corporation.
                                46

-------
                          SPECIALTY PAPERS






     Specialty paper mills produce over a thousand kinds of  paper which




is made and used  in small quantities.  Some mills produce as little  :as




two tons daily.   Many  single mills produce as many as one hundred different




grades.  They employ a wide variety of pulps and use an almost endless




number of additives.   Runs of  a  particular grade are generally short, so




that changeover losses can be  higher  than those entailed in continuous




operation.




     A number of  these employ  cotton  linters or textile fibers such as




flax, jute and some synthetics.  Most of the mills once pulping rags now




employ cotton linters.  The raw  fiber is cooked in boilers and washed in




beaters where the stock is bleached if necessary and the other materials




making up the furnish  added.   From here it goes to a stock chest from




which it is withdrawn  for preparation of the machine furnish.




     Because of the great variation of these operations, it is not possible




to give specific numbers of their sewer loses.  Howaver, where information




is needed to give some idea of the magnitude of these, reference is made




to the following  publications:
                            (See next page)
                                   47

-------
                             REFERENCES

                            SPECIALTY PAPERS


NCASI

Camp, Dresser & McKee Report on Industrial Wastes at Pittsfield, Massachusetts.

Pirnie, Malcolm, Report on Industrial Wastes at Watertown, New York.

Nemerow, N. , "Theories and Practices of Industrial Waste Treatment, Addison
Wesley Publishing Company, Reading, Massachusetts (1963).

NCASI, Technical Bulletin, Rag, Rope and Jute Pulping.

"Pulp and Paper Manufacturing, Volume II, McGraw Hill Publishing Company,

(1970).

-------
CATEGQRy XI
                       WASTE PAPERBOARD MILLS
     Waste paper is the primary furnish for waste paper board mills

although a small percentage of new  filler is .-.used to produce products
having a lining or coating.  They employ both cylinder and Fordrinier

machines and in some a special stock preparation system is employed to

refine the waste pulp and disperse asphalt which is frequently present.
This is known as the  A D or  asphalt dispersion  system. A few mills employ
a special vertiformer wet end on the paper machines.

     Numerous types of board for a multitude of uses are produced in 145
mills in the United States, ranging from crude products such as pad backing
to food boards and patent coated specialities.
     Effluent, Volume, BOD5 and total suspended solids data for 34 mills
have been  collected.  These were compiled from data collected by the
Department of Environmental Services at Rutgers University, the Michigan
Water Resources Commission, the Connecticut Water Resources Commission,
the Pennsylvania State Health Department and the NCASI.  The volume
of effluent ranged from 3.3 to 21.6 thousand gallons per ton and  it is known

that at three mills the effluent has been virtually eliminated through
clarification and reuse.  However, these mills manufacture a small number
of products of a coarse grade which makes this procedure possible.
Extended full-scale trials on complete water resue after diatomite filtration

at several other mills indicated this practice to be unsatisfactory when

a variety of high quality products were made.
     The minimum quantity of water required depends on whether or not

food packaging grades of board are produced.  If they are not, a reuse to
the extent that 7,000 gallons or less per ton of produce are discharged,
                                   49

-------
can generally be achieved.   Reuse is somewhat restricted when food




board is produced since taste and odor producing substances tend to




accumulate in the system 
-------
     These wastes are generally substantially neutral though leaning




toward the acid side due to alum used as sizing.  They do not contain




mineral acidity and can be treated biologically without neutralization.




They seldom contain much true color unless such as is imparted by the




water supply, but can be quite turbid due to the presence of clay or




titanium dioxide used in the process or entering the system with the




waste paper.  They are not toxic, but can have a high bacteria count




these being largely aerogenes and frequently some E.Coli.  They appear




to have no other undesirable characteristics.  Concentrations of suspended




solids, BOD^ - and COD are similar to that of strong -sanitary sewage




and it responds well to treatment applied to sewage.  According to




Rudolfs about 25% of the BOD is removed by settling and 30% by




coagulation and settling.  This is accompanied by total suspended solids




removals of about 85 and 95 percent respectively.




     Close to one-half of the news and wastepaper board mills discharge




to public sewage systems and more can be expected to follow.  These




are frequently available since many of these mills are in or close to large




municipalities which serve as their souce of raw materials.   Over thirty




mills treat their waste water, most by sedimentation or flotation and




coagulation.  Four employ activated sludge, three have aerated stabilization




basins and two practice storage oxidation.




     Published results from the two large activated sludge plants reveal




that they  are capable of achieving effluent BOD^ values in the order




of 10 to 30 mg/1 and total suspended solids in the order of 5 to 25 mg/1.




COD effluent values at one of these mills ranged from 65 to 101 mg/1.




Th    values will vary with the influent concentration.  Both have dif-




ficulty in disposing of the waste activated sludge.




                                 51

-------
   Data on analyses of Waste Paperboard and Mill Effluents is shown  in




Table V.  A Waste Paperboard Mill flow diagram is covered by Figure 15.
                                  52

-------
                                     * TABLE V
Production-Tons




Flow-Million  Gallons




Pounds of  B.O.D.   (Net)




Pounds of  B.O.D.  P




Pounds of  Dry Soli




Pounds of  Dry Soli




Pounds of  Vol. Sol




Pounds of  Vol. Sol




Gallons Waste Per




Fibre Loss-Percent




Population Equivalent
ANALYSIS OF WASTE PAPERBOARD AND
MICHIGAN

>ns
(Net)
3er Ton Product
Ids (Net)
.ds Per Ton Product
Lids (Net)
Lids Per Ton Product
Ton Product

Lent
MICHIGAN

>ns
(Net)
'er Ton Product
ds (Net)
ds Per Ton Product
.ids (Net)
ids Per Ton Product
Ton Product

ent
MILL #1
Survey
No.l
29.25
0.735
349
11.9
524
17.9
328
11.2
15,200
0.59
2,090
MILL #2
Survey
No.l
43.19
0.54
1,224
28.3
1,857
43.0
1,496
34.6
12,500
1.82
7,330
MILL EFFLUENTS
Survey
No. 2
35.38
0.729
344
9.7
486
13.7
381
10.8
9,830
0.57
2,060
Survey
No. 2
43.0
0.518
.957
22.3
1,080
25.1
880
20.5
12,050
1.08
5,730
Survey
No. 3
30.89
0.820
279
9.0
932
0.2
632
20.5
15,300
1.08
1,670
Survey
No. 3
43.4
0.593
870
20.1
940
21.7
785
18.1
13,650
0.95
5,210
Production-Tons




Flow-Million Gallons




Pounds of B.O.D.   (Net)




Pounds of B.O.D. F




Pounds of Dry Soli




Pounds of Dry Soli




Pounds of Vol. Sol




Pounds of Vol. Sol




Gallons Waste Per




Fibre Loss-Percent




Population Equivalent







Source:  Michigan Water Resources Commission




                                          53

-------
     Product   	
     Water    —
     Trash
     Chemicals —
     Fresh
     Water
    FIGURE 15
                                   Waste
                                   Paper
                        Waste Paper Board Mill
                            Flow Diagram
                       r

$ \
Hydro
Pulper



LI
                                              Junker
                         -"•{   Cleaner
Overflow to Sewer
                         I Trash
                             Dump
                                               Refiner
'
f
Screen
                                                            Fresh
                                                            Water

                                                              Stock
                                                 Liner
                                                 Beater
                                                 Cylinder  Type
                                                 Paper  Machine
                               Product
                                       54

-------
                              REFERENCES,

                           WASTE PAPERBQARD


1.  RidolfSj w. , "White Water Research Report", NCSI, Technical Bulletin
   Number 9 (1947).

2. Wisconsin  State Department of Health, Pulp and Paper Advisory Committee
   Reports.

3.  NCASI Technical  Bulletin #220,  "Biological Waste Treatment Case Histories
    in the Pulp and  Paper  Industry  (1968).

4.  Michigan  Water Resources Commission, "Reports on Kalamazoo River".

5.  Pulp and  Paper Manufacture, Volume  II, McGraw Hill Publishing Company,
    New York  (1970).
                                    55

-------
     CATEGORY 12
                            BUILDING PRODUCTS
   Building papers are made in generally the same manner as other coarse

papers or waste paperboard, kraft and NSSC or groundwood pulps being used as

finish.

   Building felts are produced from single refiner groundwood pulp together

with waste paper and in some instances, other fibrous  materials such as

bagasse pulp and extracted licorice roots, etc.   They are made on forming

machines of the Fordrinier or cylinder type and since the furnish is generally

hot, a very high degree of recirculation of the white water can be practiced

lowering the discharge to as little as 1000 gallons-per-ton of product.

Effluent characteristics are similar to that of waste paperboard except for

the fact that these products are impregnated with bituminous materials or

contain preservatives which can be toxic to aquatic life.  BODc values»can

run as high as 5000 mg/1  when a high degree of recirculation is practiced,

and total suspended solids in the range of from 4000 to 6000  mg/1.   They

are highly turbid and while the true color is not very high it can be

appreciable.  This waste is difficult to treat by the usual processes except

if mixed with a relatively large quantity of sanitary sewage or other dilute

effluents.  Most of the mills producing felts discharge to public sewage

systems.

   insulating board is produced from a furnish similar to that of building

felts except for the fact that the quantity of refiner groundwood is usually

much higher.  It is also made on a forming machine generally of the mold or

Fordrinier type and is produced in various thicknesses and both with and

without impregnation.   Water reuse depends greatly upon the grade produced


                                    56

-------
and this practice is reflected in the suspended solids content of the machine

effluent.  High grade products necessitate high suspended solids losses since

a substantial portion of the refined wood must be rejected from the product.

Hence the total suspended solids content of these effluents can run as high

as 3500  mg/1 and the BOD5 to 3200  mg/1  most of which can be removed by

settling.


   Most hardboard is produced by adding binders to a sheet produced in the

same manner  as insulating board and consolidating it on a wire surface in a

hot press.   This treatment removes all the moisture and sets the natural

binders present in the wood as well as those added which can be linseed, tung
                I,
or tall-oil  or  phenol-formaldehyde resins. A tvPical effluent from this

process amounts to 5.3 thousand gallons-per-ton of product containing 30 Ibs.

of BOD and 39 Ibs. of total suspended solids.

   Hardwood  is also produced by the Masonite process in which wood chips are

placed in a  "gun" under steam pressure of 1000 psig ,then exploded against a

target.  The material so produced is disc refined, washed and formed into a

wet lap which is pressed between platens of a hydraulic press having a

screen on one side.  Water is removed and the natural binders present in the

wood allow its moulding into a solid sheet.  The losses of both BOD5 and

suspended fines from this process can be high since washing of the pulp

produces a molasses-like waste.


     Figure XVI shows Insulating Board, Building Board and Hardboard, flow sheet.
                                      57

-------
Product
Water
Chemicals
Steam
                            Insulating Board,
                            Building  Board and
                            Hardboard, Flow Sheet
                                 FIGURE XVI
   Steam. ..
                                                       fFreSh
                                                  	[Water
                                                   Condensate
        Building Felt
             or     <*
        Ins. Board
   Drier
 Overflow
   to
  Sewer
Hydrau
 Press
E
ilic
                                                   Additives

                                                 Hardboard
                                     58

-------
                               REFERENCES




                           BUILDING PRODUCTS







New Zealand Forest Products, Ltd., Private Communications.




NCASI




Joint Textbook, Pulp and Paper Industry




Kleppe, P. J.  and Rogers, C.N., Report




TAPPI Air  and  Water Conference, Jacksonville, Florida (1969)
                                    59

-------
                          Other Mill Effluents







     In addition to process effluents many mills discharge water from




their utilities.  These consist of filter backwash and sedimentation tank




underflow or clean out from water treatment, boiler blow down and cooling




water.  In some instances the latter is salt or brackish water.   In




addition, mills burning bark and/or coal usually sluice ash to a. ponding




area.  Frequently the grits and dregs from kraft recovery systems are combined




with this flowage.   In addition to these effluents, some mills dispose




of process clarifier underflow in land fill areas.   In respect to the




latter good practice dictates the return of overflow water to the




waste treatment system since it can be high in both suspended solids and




BOD.  The overflow water from ash sluicing ponds generally carries but




a small pollution load which frequently is discharged- only during periods




of high precipitation.  Hence,  it is diluted with rain water and th'e




receiving stream at relatively high run-off.
                                  60

-------
              WATER QUALITY PARAMETERS Iff ESTABUSHI1IG SKWL
                   FOR PULP, PAPER
       tal_smd Volatile Suspended Solids_

      Basic considerations related to the raw materials "being processed

and the process requirements results in the presence of organic matter,

dissolved and suspended in the process wastewaters.  Therefore, "biochemical

oxygen demand (BOD),  total and volatile suspended solids are parameters

recommended for measurement at all mills.  These three parameters measure

the most significant  components of these vastewaters and provide the basis

for quantitative  evaluation of treatment effectiveness.

      BOD   the principal product of the paper-making process is wood fiber,

the cellulose component of wood.  To get the fiber freed from the wood re-

quires a separation of the fiber from its binders usually by a digestion

process which, in turn, may convert up to 50$ of wood solids into soluble

organics such as  wood sugars, lignins,  and hemicelluloses.  These solu-

bilized extracts, along with the chemicals used in digestion, have very

limited commercial use, therefore, constitute the principal waste of the

papermaking process.  As soluble organic matter the sugar and cellulosic

components are biodegradable and cause heavy oxygen depletion if discharg-

ed into natural waterways.  Thus, the BOD test serves to measure the

biochemical oxygen consuming capability of the wastewater.

      Since this  test can be quantified in terms of quantity of oxygen

required, it is one of the fundamental measurements of wastewater

characteristics,  and  is particularly applicable to wastewaters of the

pulp and papermaking  process.

      The EQD5 or 5 -day test is the agreed standard test by which all
                                    61

-------
organic putrescible waste-waters are evaluated.  It is recommended, there-



fore, that all waste-waters of the pulp and paper-making processes be re-




ported in terms of the BOD5, as described in the latest edition of



"Standard Methods".  This procedure, being based on empirical considerations.




and being dependent upon biochemical processes using living organisms,



must be performed with careful attention to all details.   Even so, the



results obtained are not universally comparable, particularly when attempt



is made to compare raw and primary effluent with secondary effluent.   The



FWPCA Manual "FVZPCA Methods for Chemical Analysis of Water and Wastes"



November 1969, recognizes this in its appraisal of the method, but can



give no practical alternative.  Yet, the universal applicability of the



test to all wastes containing putrescible organic matter requires that it



be used until a better test has been demonstrated.



      Other BOD intervals, i.e.,BOD 20 have been utilized, and have



applicability for specific purposes.  However, these would serve no use-



ful function in terms of wastewater quality assessment since nearly all



available historical data on effluent or process wastewaters has been re-



ported as BOD5-  It should be pointed out that BOD is not a requirement



of established stream quality criteria.  This is due to the basic



character of the test, which, in reality, is an assessment of oxygen con-



suming potential.  Such a criterion has been found to be unrealistic for



^tream quality assessment.  The National Technical Advisory Committee on



Water Quality Criteria in its review and recommendation of criteria for



the various water uses to be accommodated did not propose BOD as a



criterion, since the BOD effect, namely the dissolved oxygen level, is
                                    62

-------
the primary criterion.   However,  effluents must "be judged on their




Potential for affecting stream criteria,  consequently, the EOD5 is a




much more significant effluent criterion  "because of its adverse effect on



steam  oxygen resources.
      In parallel with the EOD5 effect  of mill vastewaters are the




visible solids  that result from these processes.  There are two basic




types of solids from these mills;  those of inorganic substance and those




of organic character.   In general,  the  organic fraction is the more




damaging if allowed to escape to the stream, because of its oxygen demand-




ing sludge forming tendencies when allowed to settle under quiescent




conditions.   On the other hand,  the loss of organic solids implies loss




of the  fiber which is  the sought for product.  Thus, heavy organic solids




losses  can imply inefficient fiber handling and consequently, a heavy




profit  drain on the mill.




      Inorganic solids result from the  primary wood handling steps in the




clean up of the wood before 'digestion,  and in the paper making step where




specific materials are added for opacity control or as fillers and in




 coatings.   The properties  of these solids are somewhat different in that




the vood handling process  solids reflect the randosized contact of the




raw material, in its excursion to the mill, in the form of mud, clay and




silt washed from the vood.  These solids, in general,  settle adequately




and are removable in conventional treatment devices.  In contrast, the




"fillers" in the paper making process are substances with specified




properties, one of which is the ability to remain in suspension.   When




these substances escape to the environment they my cau.3e a relatively
                                    63

-------
greater visible impact "because they produce a greater turbidity in relation



to the quantity lost.  Although the stream quality effects of these in-



organic suspended solids are not as serious as the organic solids,



neverthless they create objectionable aesthetic effects and they do settle



and may interfere with the natural ecology by smothering spawning areas




of fish and affecting insect and other macro vertebrate propagation.



    Because these suspended solids have differing properties depending



upon their organic or inorganic nature, it is pertinent to distinguish between




or to  characterize the  nature  of the solids discharged.  This is determined by




differentiating between volatile and non-volatile fraction of the solids



that are present in the wastewaters.  The method for suspended solids



(non-filterable solids) is specified in the FWPCA manual, previously



cited, and requires filtration through a glass fiber filter of specified



pore size, followed by  drying at 103-105°C.  The "Standard Methods" pro-



cedure offers alternatives in filtration media such as the "asbestos mat"



and the membrane filter.  Historical data based on the "Standard Method"



should be acceptable for this test.  However, the "Federal" method



should be specified for future testing.



       The method for volatile suspended solids is specified in "Standard



Methods as Volatile and Fixed Suspended Matter".  The "Standard" method



uses an electric muffle furnace set at 600°C.  The "Federal" (FWPCA manual)



specifies 550°C as the  temperature of the electric muffle furnace.  Other-



wise both methods are identical.  Historical data based on the "Standard"



method should be acceptable for this test.  This test, therefore, will



characterize the type of suspended matter in the waste in terms of




"Volatile or Fixed" residue.  In general, the volatile fraction represents
                                     64

-------
 the organic component of suspended solids found in an effluent.



.Chemical Oxygen Demand (COD)




        The National Council for Stream Improvement, Tech Bulletin 193,



 1966 reports on a study of 60D/BOD relationship of raw and biologically



 treated Mill Effluents. It concludes;




             "Based on the results obtained it does not appear possible



 to develop time-automated treatment process and effluent discharge con-



 trols for rapid BOD estimation based on the COD test.  Examination of



 BOD, COD, and lignin content relationships on 352 samples of untreated



 and treated pulpmill effluents showed no fixed relationship  between



 these values.  It is probable that materials other than lignin which are



 resistant to biological oxidation are present in the waste,  as well as



 some lignin materials do decompose.  Possibly these are functional groups




 of the large lignin molecule.  There is also wide variation  in momentary



 relative concentration of the various constituents present in these wastes.



 Correcting COD values for oxygen equivalent of the lignin content of both



 untreated and treated wastes significantly lowers the COD/BOD ratio.




 However, it does not yield a ratio sufficiently constant for reliably




 estimating BOD by this technique.





        In view of the large* number of representative samples used and




 the well-controlled laboratory techniques employed, it appears that final




 solution of this problem will depend on the separation and measurement  of




 those constituents contributing to both chemical and biochemical oxygen





 demand".
                                    65

-------
        This is not surprising, nor has there yet teen discovered any




 physical  chemical procedure that correlates -well with the BOD test.  How-



 ever,  this  shortcoming, the lack of correlation, is not sufficient to rule



 out a  test  procedure that can provide meaningful information that may be



 translated  into stream or  effluent quality appraisal.  The dichromate



 procedure for COD (with chloride correction) has been recognized as a



 "Standard"  method.  This method seems to correlate well with filtured



 domestic  sewage and with wastewaters having characteriistics similar to




 domestic  sewage.  A less favorable correlation is experienced with treated



  effluents, with the COD/BOD ratio increasing with greater bio-



 logical stabilization.  This serves to indicate that biologically stabi-



 lized  effluents contain organic components that react very slowly bio-



 logically,  but retain chemically oxidizable properties„  The COD test is



 also more easily repeatable since its conditions are better controlled.



 On the other hand, there is no established usage of the COD test in which



 it is  readily quantified. Treatment plant designs are strictly on BOD/



 suspended solids criteria, especially through secondary treatment stages.



 As yet, criteria for advanced treatment have not been thoroughly standard-



 ized.  These criteria would more likely reflect the tertiary process that



 was needed  to remove a specific residue from secondary«treatment, i.e,



 residual  ammonia, carbon, phosphorus, etc.



        Therefore, the COD test as currently practiced, provides some use-



 ful information that may be utilized to provide a general classification



 of the oxidizable carbon content of a wastewater or its receiving stream,



but the interpretation of COD values, without other qualifying data,



provides  very little of value for classifying effluents or the resultant



 effects on stream quality.  Currently the usage of COD data is in process
                                    66

-------
control wherein intimate knowledge of the process can be used to interpret
   e COD value  of  effluents and to make appropriate process adjustments.
It is therefore recommended that the COD test not he required as a deter-
mination  of  Standard Raw Waste loads from the pulp, paper and paperboard
industries.
Turbidity
        This empirical test differentiates the light scattering properties
of fluids.   Its unit of measurement in water and wastewater analysis is  the
Jackson Turbidity Unit (JTU).  Turbidity is a qualitative criterion for
aesthetic uses, which require such waters to be free of substances that
produce objectionable turbidity.  Another quantitative (but indirect)
criterion is the  Secchi disc test to measure clarity,which is generally
used for  recreational waters.
        As a criterion for uses for public water supply, the absence,of
turbidity is  considered desirable, as is the absence of a frequently
changing  turbidity, to the treatment plant operator.  Because turbidity
can not define other properties of the suspended particles causing it,
the water supply  criterion remains qualitative.  The criteria for uses
for the propagation of fish, aquatic life and wildlife are set to a
limit of  50  JTU for warm water streams, 10 JTU for coldwater streams,
25 JTU for warm water lakes and 10 JTU for cold water lakes. These
criteria  are based on the probable settling out of the turbidity causing
particles on spawning grounds of fish and habitats of aquatic  insects,
resulting in interference in the life cycles of these organisms, and on
light penetration requirements for aquatic life propagation and produc-
tivity of stream bottoms.  In marine waters, a qualitative criterion is
                                    67

-------
recoEmended which states that no effluent should be added which causes



changes in turbidity unless it has been shown that such will not be de-



leterious to aquatic life.  For other water uses (Agricultural,Industrial)




turbidity of raw water does not appear to be a serious impediment, and is



not specified as a specific criterion for these uses.  Turbidity and



suspended solids parameters are not synoymous.  Suspended Solids (S3)



measures nonfilterable particulates in the fluid, turbidity meansures the



light scattering properties of a fluid.  Where SS is present, turbidity is



always found.  However,  sometimes turbidity may be observed under condi-



tions of extremely fine particle size, which pass through the standard



filters used for SS measurement.



     In the mill, turbidity is found in all wastewater systems carrying



suspended solids.    High turbidity can be due to mud, clay and detritus



carried on logs and removed during washing operations, in fiber losses



during processing, and in white water losses from the paper making process.



In the latter instance, the finely divided materials used for fiber, such



as clay, calcium carbonate, titanium oxides, and the various chemicals



used in special finish coatings may escape detection as Suspended Solids,



but would be readily detected as turbidity.  Historical data on turbidity



of mill process steams is non existent, since this has traditionally been



reported as Suspended Solids.  However, the quality effect on water uses



that distinguishes turbidity from Suspended Solids requires that effluents



be characterized using both parameters.  It is therefore recommended that




turbidity be a standard measurement of plant effluents only, since its



usage in the operating mill process flows has no important significance.
                                    68

-------
Color-




     Basic  to the  conversion of wood into paper is the extraction of color



 rom the raw material or its converted products during the refining pro-



cesses.   The origin  of most of the color in the wastewaters of these pro-



cesses are  the  lignins and tannins of the wood.  As the fiber is separated,




these hinders are  solubilized into the color extracts found in the result-




ing  wastewaters.   Therefore, all processes in pulping and "bleaching con-



tribute  waste-water with more or less significant qualities of color per



unit of  product.   Along with Suspended Solids and BOD, color is a "basic




parameter that  characterizes the wastewaters of -this industry.




     A second characteristic of the color extracted from these processes is



its  refractory  nature when present in the water environment.  It persists



indefinitely in solution, having  practically no  "biological activity,



therefore its reduction must "be through chemical attack or "by absorption.



     The need to measure color and to limit its presence in receiving



vaters is spelled  out in the quality criteria for aesthetic, water supply,



fish, aquatic and  wildlife propagation and some industrial uses.  For



aesthetic uses  the criteria specify the absence of objectionable color.



For  water supply uses, the criteria specify a limit of 75 color units



(cobalt-platinum standard units).  This standard permits the treatment



plant to produce a satisfactory water with moderate dosages of coagulants




and  chemicals.   For  fish, aquatic life and wildlife propagation, the




criteria specify the need for at least 10$ of incident light to reach the



bottom of a desired  photosynthetic zone in order to maintain adequate




dissolved oxygen levels.  The conversion of this requirement into standard



color units is  not possible because of associated turbidity, fro^ natural
                                     69

-------
and -waste-water sources.  However, a value above 50 units has "been signi-




ficant in limiting photosynthesis  and having a deleterious effect upon




aetuatic life, particularly phytoplankton and the benthos.  Some specific




industrial vater users primarily the food and beverage producers specify




raw water color to "be limited to 5 units.  However, industry in general




sets no specific limit, since its varied  uses usually require a complete




treatment for removal of most substances including color.




     The standard method for color measurement is in terms of platimum-




cobalt unit of color, as specified in "Standard Methods" for water.




     Since the color of the wastewaters from pulp, paper and paperboard




manufacture have the characteristic brown color very similar to the




platinum-cobalt system, there is little need to modify this procedure




except for those special processes in .which dyes are used to introduce




 other colors.  Gehm suggests,  however, that all mill effluent measurements




be made at pH 7.6 because there may be significant pH effect on the color




of the wastewater being measured.




     It is recommended therefore that color measurement should be a




requirement in the quality evaluation of these wastewaters.




pH (Hydrogen Ion Concentration)




     Processes used in pulp, paper and paperboard manufacture result in




wastewaters with pH values encompassing both ends of the scale, from




highly acidic level of 1.2 to alkaline levels above 12.0.  Water quality




criteria for nearly all uses allow the pH range to remain within the limits of




5.0 to 9.0, with some uses, i.e., marine organisms having much more narrow




limits (6.7-8.5).   Adverse effects, such as corrosion of metals and concrete




occur at both ends of the pH scale.  Toxicity effects of some substances
                                    70

-------
 re enhanced by changes in pH, such as ammonia  toxicity which increases




   higher pH values, and Cyanide toxicity which increases at lower pH values.




It: is universally recognized that pH is a significant water quality criterion




and that its acceptable levels lie within narrow limits surrounding the




neutrality level of 7.0.  Therefore, all effluent measurements should in-




clude pH as one of the required parameters to be reported.




     It should be understood that pH measurement by itself does not indicate




the acidic or alkaline effect of the wastewater discharge.   To evaluate this




effect it is necessary to have information on the alkalinity or acidity of




the wastewater and of the receiving stream.   However, so long as the pH




level of the effluent is within the water quality criteria set for the




receiving waters, there is very little likelihood that the pH changes




in the stream caused by the wastewater assimilation will exceed those




criteria.




Other Significant Parameters




     The parameters that have been  reviewed  above have applicability to nearly




all the mill wastewaters of the industry.  Those to  be discussed below may




be applicable to some process wastewaters and  effluents, but are not




universally applicable  for all mills  therefore  they  are recommended only




for those specific conditions that  may be critical to a particular receiving



body of water.




    - Medium Tolerance Limit
     This is a bio-assay procedure  that  is  used to establish a concentration




level of the substance under test that will result in survival (or non injury)




to fifty percent of a test population during a specified time interval.  A




static procedure and a flow-through procedure are used in measuring this




criterion.  The static procedure has been standardized in "Standard Methods"
                                    71

-------
using fish as the test organism for those instances in which the material

"being tested is persistent, non volatile and without  significant oxygen

demand.

     It is well known that process wastewaters from various pulping processes

exert varying degrees of toxic effect upon the ecology of receiving waters.

It is also well known that "biological treatment reduces these toxic effects

significantly.  Since toxicity tests are not yet recognized universally as

standard tests and they are relatively expensive and tedious to perform, .it

would seem logical to suggest that these tests "be required only under those

circumstances that would constitute a sensitive relationship "between the use

of a body of water for -?7astewater disposal and its use for the propagation of

valuable fish and food organisms.  In these instances, the test should "be

performed under continuous flow through conditions where feasible.   The ultimate
 purpose of  the test  would  be its use. as  a regulator of  the discharge

 rate of the final effluents  from the affected mill.

  Heavy Metals
      Low concentrations of chromium, nickel,  lead, mercury  and  zinc have

 been found  in process wastewaters  of the industry, and  particularly in the

 waters resulting from the  pulping  and bleaching  operations.   These metals

 have known  toxic effects on  aquatic life, and  their presence in water

 for human consumption is limited to very low concentrations.  Mercury

 and lead may be present in the caustic used  in  the pulping  process,

 chromium and nickel  are picked up  as corrosion  products along with iron

 from the process equipment.   Zinc  is used in groundwood bleaching  operations.

 It would serve no useful purpose to require  analysis  of these substances

 in the various process wastewaters since they are only  minor or incidental

 components  of the basic materials  being  processed.  However,  their

 absence from wastewater discharges should be a  basic  requirement and

 analysis to prove their absence should be specified.

                                    72

-------
and Dissolved Solids
                                                     in
      Digestion  and bleaching  operations  in a pulpmill can result in a




    dup of  significant  levels of acidity, alkalinity and dissolved salts




the wastewaters from  these  operations.   Dissolved salts are also accumulated




in steam  boiler blowdown  and  in cooling  tower blowdown.  Where recovery




of chemicals  is practiced,  as in the more modern kraft and sulfite mills,




losses of acid  and alkaline components are minimized.




      For  purposes of  determining the resultant pH effect of a plant discharge




on the receiving water  body,  and for the regulation of such discharges in




order to maintain pH  criteria, it  is necessary that the acidity or




alkalinity  of discharges  be known.  Therefore, these tests should be




a requirement   for all  effluents.




     Dissolved  salts, when  added in quantity to cause a significant increase




in the ionic  levels of  the  receiving body of water, may adversely affect




some  forms  of natural biota common to the water course.  For these reasons^




addition  to natural waters  which are to  be protected for fish, aquatic life




and wildlife uses have  been limited to a level that will restrict such




increase  to • a  factor 1/3 greater  than the background ionic level.  In




addition, the maximum concentration of the ionic components should not




exceed the  ionic effect of  a  1500 mg/1 solution of sodium chloride;




(50 milliosmoles, in terms  of  osmotic effect).  Where public water supply




is to be protected, the total  dissolved  solids level of 500 mg/1 is the




limiting criterion for  this parameter.   Specifications for industrial




wastes at the raw water level  are usually less restrictive than the




criteria for public water supply and fish and wildlife uses.  This is




due to the .wide range of quality required in industrial processing,
               73

-------
which requires that the raw water be treated to a needed specification.




For these uses, increases in dissolved salt concentration result in an




increased economic burden to the user, especially in those uses that require




deionization.




     It is therefore concluded that the total dissolved solids test be




required of all effluents from this industry.




Coliforms




     The use of the total coliform test as a quality criterion for natural




waters is rapidly being displaced by the fecal coliform test.   This




differentiation is significant to the assessment of natural water quality




for contact recreation purposes and for public water supply because it




is being universally recognized that the protection of the public health




is served better through the elimination of those organisms that are




directly related to human and animal fecal matter.




     It has also been amply documented that many of the wastewaters from




this industry have a property of stimulating the multiplication of coliform




organisms because of the presence of various carbohydrates that are extracted




from wood during the pulping process.  The resultant high coliform con-




centrations may appear significant, but invariably, these are  classified




as non-fecal types, with only a very small fraction testing out as of fecal




origin.  Where mill sanitary sewage is combined with process wastes,




there is, of course, a relatively higher fecal coliform content.




Based on these considerations the total coliform test should no longer




be a requirement for effluent bacteriological quality.  It-should be




replaced by tests that differentiate the presence of the fecal coliforms.
                                   74

-------
     Excessive concentrations of the  nutrient   elements phosphorus and

nitrogen, when present in a, natural water body have been implicated as

the causitive agents in overfertilization or eutrophication leading to

overgrowth of undesirable aquatic organisms.  Sources of these nutrients

are the wastewaters from municipal wastes and some industrial wastes.  The

processes in use by the pulp paper and paperboard industry result in

wastewaters that are usually deficient in one or both of these critical

nutrient elements.  Therefore,  it has been a general practice to add

calculated quantities of nitrogen and phosphorus to the biological treatment

processes in order to optimize  treatment.  Where secondary biological

treatment is being practiced, it has been determined that a ratio of

1:5:100 of phosphorus to nitrogen to BOD should be maintained for optimum

treatment.  It is therefore concluded that there is very little likelihood

of excessive nutrient concentrations being found in the process wastes or

wastewaters from this industry, therefore, no useful purpose would be

served to require nutrient analyses of these waters.
                                    75
                                                  ft U.S. GOVERNMENT PRINTING OFFICE : 1971 O - 420-295

-------
                         TABLE VI
STANDARD RAW WASTE LOADS FROM PULP AND PAPER MANUFACTURING PROCESSES

-------
PAGE NOT
AVAILABLE
DIGITALLY

-------
PAG E N OT
AVAILABLE
DIGITALLY

-------
PAGE NOT
AVAILABLE
DIGITALLY

-------