PLYWOOD PLANT
GLUE WASTES  DISPOSAL
     PROGRESS REPORT
       February 1968

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                PROGBESS  REPORT

       PLYWOOD PIANT GLUE WASTE  DISPOSAL
                  Prepared  by

              Danforth  G. Bodien
           Technical Projects  Branch

                Report  No.  PR-2
        U. S. Department  of  the  Interior
Federal Water Pollution Control  Administration
               Northwest  Region
      Pacific Northwest Water Laboratory
               Corvallis,  Oregon
                  February 1968
                0c ft of the interior
                Edison, W. J. 08817

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                          ABSTRACT






     In the States of Oregon, Washington, Idaho, Montana, and




California, 158 plywood plants generate an estimated 6.2 million




gallons of waste per day from the cleanup of glue mixing equip-




ment and glue spreaders.  The waste is toxic and high in pollu-




tional strength.  Treatment of these glue wastes varies from plant




to plant but generally consists only of solids separation or the




removal of suspended matter.  Further investigations are needed




to determine which treatment methods will solve the pollution




problems caused by the discharge of these wastes.

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                           TABLE OF  CONTENTS
                                                       Page
   I.   INTRODUCTION
       A.  Problem	1
       B.  Objectives	2
       C.  Authority	2
       D.  Acknowledgments	2
  II.   SUMMARY
       A.  Findings	4
       B.  Conclusions 	  4
 III.  PLANT SURVEY  	  5
  IV.  PLYWOOD PLANT CHARACTERISTICS

       A.  Locations and Number  	  8
       B.  Production	8
       C.  Operations	11
   V.  WASTE CHARACTERISTICS

       A.  Waste Quantity	18
       B.  Waste Quality	28
  VI.  DISPOSAL OF WASTE

       A.  Methods in Use	33
       B.  Incineration of Waste	36
 VII.  PROPOSED STUDIES  	 40


VIII.  SELECTED REFERENCES 	 41


  IX.  APPENDIX

       A.  Definition of Terms	43
       B.  Plywood Plant Locations  	 47

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                            LIST OF FIGURES




No.






 1      Plywood Plant Flow Diagram	12






 2      Average Glue Waste Flows (Plant 1)	20






 3      Daily Average Glue Waste Flows (Plant 2)  ....  22






 4      Daily Average Glue Waste Flows (Plant 3)  ....  23






 5      Daily Average Glue Waste Flows (Plant 4)  ....  24

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                            LIST OF TABLES

No.                                                         Page

 1    Number of Plants by Types of Plywood 	     6
 2    1966 Plant Production by Type and Grade of Plants
        Surveyed 	  ,
 3    Number and Percentage of Plants Surveyed 	     9


 4    1966 Plant Production by Types of Plywood 	     10


 5    Number of Glue Spreaders for Plants Surveyed  ...     13


 6    Number of Spreader Shifts for Plants Surveyed ...     14


 7    Green Ends, Cold Decks, and Log Ponds	     16


 8    Number and Size of Log Ponds at Plants Surveyed .  .     17


 9    Characteristics of Plants Used in Discharge Study  .     19


10    Glue Waste Discharge Measurements	     25
11    Ingredients of Typical Exterior and Interior Glue
        Mixes	      29
12    Chemical Analysis of Plywood Glue	      31


13    Disposal Methods of Plants Surveyed  	      34


14    Chemical Analysis of Settled Effluent	      35


15    Incineration Test of Exterior and Interior Glue  .      38

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                            PROGRESS REPORT
                   PLYWOOD PIANT GLUE WASTE DISPOSAL
                           I.  INTRODUCTION


     A.   Problem

     The cleanup of glue spreaders at 158 plywood mills throughout

the study area produces a waste that is high in pollutional strength

even though volumes are quite low.  At the present time the State

of Oregon rates this waste as their primary pollution problem

based on the number of complaints received.

     The glues used in the plywood industry are of three basic types:

the blood soya variety used for interior grade plywood; the phenolic

formaldehyde variety used for exterior grade plywood; and a urea

formaldehyde glue used for hardwood paneling.  Each type presents

its own problem and combinations of two or more types of glue present

additional and more complicated problems.

     The blood soya glues produce an alkaline waste with a high

oxygen demand.  Coagulation of the glue solids may cause large

masses of solids resulting in sewer stoppage.  The waste also

supports the growth of Sphaerotilus sp.

     Phenolic formaldehyde glues produce a toxic waste which is

alkaline.  The waste from this glue also creates  color, taste,

and odor problems.
                                   -1-

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     The urea formaldehyde glues also produce a toxic waste,  but




it is acidic.  These glues are used for less than 8 percent of




the plywood production in the study area.   For this reason, the




majority  of work has been done with the interior and exterior




glues.




     B.  Objectives




     This study is to determine the magnitude and extent of the




problem created by the disposal of glue wastes, review the charac-




teristics of plywood glue wastes, and recommend methods of treatment




for these wastes.  The study area includes the States of Oregon,




Washington, Montana, Idaho, and California.  Basic information on ply-




wood plants was collected from plants in all five States while field




work has been confined to plants in Oregon that are representative




of those in the industry.  This progress report covers the preliminary




phases of the project.  A final report will be issued later covering




the entire project.




     C.  Authority




     The Pacific Northwest Water Laboratory of the Federal Water




Pollution Control Administration, Northwest Region, was requested




by the Oregon State Sanitary Authority, letter dated January 19, 1966,




to study methods for disposing of glue wastes from plywood plants.




The Federal authorization for this study was from the Federal Water




Pollution Control Act, as amended.




     D.  Acknowledgments




     Acknowledgment is given the American Plywood Association for






                                   -2-

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their valuable assistance in conducting the survey.




     Special thanks to the Borden Chemical Company at Springfield,




Oregon, for their donation of glue ingredients and their assistance




in explaining and defining techniques involved in the preparation




of the mixes.




     Thanks are due to the personnel of the many plants visited.




Their interest and cooperation is appreciated.
                                   -3-

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                             II.   SUMMARY






     A.  Findings




          1.  Some 158 plywood plants in the study area generate




an estimated 6.2 million gallons  of waste per day from the cleanup




of glue spreaders and glue mixing equipment.




          2.  Water usage at plants varies greatly with no apparent




relationship to amount or type of plywood produced.




          3.  Both exterior and interior grade glues exhibit high




pH and COD.  The exterior grade glue is high in phenol but low in




nitrogen and phosphorus content.




          4.  Interior and exterior glues each contribute approxi-




mately 50 percent of total waste  based on production figures.




          5.  Most plywood plants utilize some sort of settling tank




which removes the wood chips and  some of the glue solids, but some




plants still dump raw waste into  rivers, the ocean, and other receiv-




ing bodies of water.




          6.  Glue solids can be  burned at high temperatures with




small percentages of ash being produced.




     B.  Conclusions




          1.  Water usage at most plants far exceeds that required




to wash down the spreaders and glue-mixing equipment.




          2.  Proper maintenance  of settling tanks and ponds is




neglected until they become inoperative.  This lack of maintenance




leads  to low efficiencies.
                                   -4-

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                          III.  PLANT SURVEY






     Plywood plants vary with respect to many parameters such as




size, type of waste generated, and waste disposal methods.   To gain




an understanding of the plywood industry two methods were employed.




The first involved personal visits to 50 plants; all in the State of




Oregon.  The second method consisted of obtaining from the  American




Plywood Association (A.P.A.) the information they had collected from




a survey of their plants.  This survey was concerned with production,




operations, waste generation, and disposal practices.




     To obtain a good response, the A.P.A. had their plant  supervisors




personally fill out a questionnaire when they visited each  plant in




their district.  This method gave a 100 percent return for  the plants




belonging to the A.P.A.  From the results listed in Table 1 and Table




2, it can be seen that the survey represented about 67 percent of




the plants and 70 percent of the production in the study area; this




appears to have been a representative sample of the industry.
                                   -5-

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                            TABLE 1




            Number of Plants by Types of PlywoodfL/
State
California
Idaho
Montana
Oregon
Washington
Totals
Softwood
Plants
17
4
6
84
22
133
Hardwood
Plants
4
0
0 ,
2
_2
8
Mixed
Plants
1
:r 0
0
6
10
17
Total
Plants
22
4
6
92
34
158
a/
' 1967 Plywood and Board Products Directory
                                -6-

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                  IV.  PLYWOOD PLANT CHARACTERISTICS
                                                        t

     A.  Location and Number

     The location of the 158 plywood plants in the five-state study

area is shown on Plate 1 in Appendix B.  The plants are concentrated

in the Willamette and Rogue River Valleys in Oregon and the Puget

Sound area in Washington.  Table 3 shows the distribution by state

of the 158 plants.  As can be seen, Oregon has 92 plants or approxi-

mately 58 percent of the total.  Table 1 gives the breakdown by type

of plywood produced by the plants surveyed.  Comparison of the tables

shows that a good cross-section was obtained by the survey.

     B.  Production

     Plywood production for 1966, which was a normal year, is given

in Table 4.  These data give the hardwood and softwood production by

states and show that in the study area the softwood makes up 92.1

percent of the total.  The production in the State of Oregon in 1966

was 64 percent of the total for the five states in the study area.

     Table 2 gives the 1966 production for the plants surveyed.  In

this table, the softwood production is further divided into interior

and exterior grades of plywood.  The survey shows that the total

production of interior and exterior grades is very similar, being

48.0 percent and 48.4 percent, respectively.  Hardwood plywood

production accounts for the remaining 3.6 percent.  Since each type

of plywood uses a different type of glue, these data indicate the

relative amounts of the glues used.


                                   -8-

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                            TABLE 3
                                                  a/
State
California
Idaho
Montana
Oregon
Washington
Totals
Number
Plants
22
4
6
92
34
158
          Number and Percentage of Plants Surveyed'


                                    Number Plants      % Plants
                                      Surveyed         Surveyed

                                            11               50

                                             2               50

                                             4               67

                                            59               64

                                            30               88

                                           106               67
iA.P.A. Survey, 1967
                               -9-

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                            TABLE 4
                                                   a/
          1966 Plant Production by Types  of Plywood
          Softwood Production   Hardwood Production
Total Production
State
California
Idaho
Montana
Oregon
Washington
Totals
7
/o
(Sq.Ft. 3/8" Basis)
1,277,000,000
293,100,000
456,000,000
7,948,350,000
2,150,600,000
12,125,050,000
92.1
(Sq.Ft. 3/8" Basis)
115,500,000
	
	
499,450,000
427,500,000
1,042,450,000
7.9
(Sq.Ft. 3/8" Basis
1,392,500,000
293,100,000
456,000,000
8,447,800,000
2,578,100,000
13,167,500,000

a/
 1967 Plywood and Board Products Directory
                              -10-

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     C.  Operations




     To help understand the plywood operations, a flow chart of a




complete plant is shown in Figure 1.  This flow chart also indicates




sources of solid and liquid wastes.




          1.  Green End




          The green end of a plant involves the storage and handling




of logs through the process of turning them into veneer.  Storage of




logs may be through the use of a log pond, cold decks, or a combina-




tion of both.  Log ponds at plywood plants usually serve as a disposal




site for the glue wastes.  This rids the plant of the glue waste but




usually complicates the pollutional problems caused by the log storage




itself.  Cold decking also causes some pollution problems; water




sprayed over the logs to keep them from checking usually finds its




way into the log pond or to another receiving body of water.  Table 5




presents data on green ends, log  ponds, and cold decks.  Of the plants




surveyed, 82.1 percent have green ends.  Of these with green ends,




63.2 percent have log ponds and 59.4 percent have cold decks.  Table 6




presents more detailed information on the log ponds.  The average



size log pond for the plants surveyed was 17 acres with a range from one-




half to 100 acres.




          2.  Gluing




          The first source of glue waste comes from the washdown of




kettles and equipment used to mix the glue ingredients.  A typical




plant, which produces 100,000,000 square feet of plywood per year,




approximately 50 percent exterior grade and 50 percent interior
                                  -11-

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                               TABLE  5
                                                   a/
               Green Ends,  Cold Decks, and Log  Ponds
             Plants Surveyed
                  with
   Average
for 5 States
                Plants  Surveyed
                     with
State
California
Idaho
Montana
Oregon
Washington
Green Ends (%)
90.9
100.0
100.0
83.1
73.3
Cold Decks
72.7
100.0
100.0
57.6
50.0
W





82.1
59.4
Plants Surveyed
     with
 Log Ponds (%)

     27.3

      0.0

     16.7

     72.9

     56.7


     63.2
    a/
      A.P.A.  Survey,  1967
                                -13-

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grade, makes about 11 batches per day of interior glue and 9




batches per day of exterior glue.  This amounts to approximately




400,000 pounds of exterior and 350,000 pounds of interior glue




per month.  The mixing equipmtnt may not always be washed between




batches, but when it is washed, only a small amount of water is




used.  Thus, the waste volume from this phase of the operation is




a small but highly concentrated part of the total waste.




          The second source of glue waste is from the spreaders




themselves.  Table 7 gives data on the number of spreaders in the




plants surveyed.   As can be seen, the average plant has approximately




three spreaders with a range from one to nine.  Of more interest




is the number of spreader shifts per day.  Table 8 contains data




on spreader shifts for the surveyed plants.  The average plant




has slightly over six spreader shifts per day with a range from




one to twenty.   These spreaders are usually washed down once per




shift when interior glue is used and at least once per day for




exterior glue.   The difference is due to the fact that the interior




glues have a pot  life of 6 to 8 hours whereas the exterior glue




lasts almost indefinitely.  The accumulation of wood chips in the




pans of the spreaders usually necessitates  cleaning the exterior




glue spreaders  at least once per day.
                                  -15-

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                            TABLE  7

                                                   a
        Number of Glue Spreaders for Plants Surveye'
State
California
Idaho
Montana
Oregon
Washington
Number
24
3
10
179
94
Average/
Plant
2.2
1.5
2.5
3.0
3.1
Max./
Plant
4
2
4
9
6
Total        310


Average for 5 States           2.9


Maximum for 5 States


Minimum for 5 States
a/
-A.P.A. Survey, 1967
                                                       Min./

                                                       Plant


                                                         1


                                                         1


                                                         2


                                                         1



                                                         1
                              -16-

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                             TABLE  8


                                                     a/
         Number of Spreader Shifts  for  Plants  Surveyed

State
California
Idaho
Montana
Oregon
Washington
Total
Number
42
8
25
406
185
Average/
Plant
3.8
2.0
6.3
6.9
6.2
Max./
Plant
7
5
11
20
16
Min./
Plant
1
3
4
2
1
 Total      666



 Average for 5 States      6.3



 Maximum for 5 States                    20



 Minimum for 5 States
-/A.P.A. Survey, 1967
                              -17-

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                       V.   WASTE CHARACTERISTICS







     A.   Waste Quantity




          1.   Measured Waste Discharges




          Waste flows were measured at four plants  over periods




ranging from 6 weeks to several months.  A different scheme was




used at  each plant for these measurements due to equipment availa-




bility and accessibility to the waste stream.  The  plants where




flows were measured will be referred to by number.   Pertinent data




on the four plants are in Table 9.




          At Plant Number 1, a water meter was placed in the wash-




water line adjacent to one of the four glue spreaders.   This meter




was read at various time intervals  over a 7-month period.  The meter




readings were multiplied by four, and the average flows were computed.




Figure 2 shows these flows for the  7-month period.   The average  flow




for the  7-month period was 12.9 gpm, and the average flow for the




working days in the period was 18.2 gpm.




          At Plant Number 2, a 45-degree V-notch weir and water level




recorder were installed in a ditch  between the plant and the settling




pond.  This proved to be a bad arrangement as the weir  was soon  plugged




with glue and wood chips.   The weir was removed and an  alternate plan




was sought.  At this plant, the settling pond effluent  was pumped




into the log pond.  The pump was controlled by a set of probes.   The




recorder was placed on the pond.  The pond area was measured and
                                  -18-

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                            TABLE 9


       Characteristics of Plants Used in Discharge Study

Plant
Number
1
2
3
4

1966 Production-'
(Sq.Ft.3/8" Basis)
100,000,000
135,000,000
100,000,000
70,000,000
Exterior
Grade
(%)
50
0
25
75
Interior
Grade
(%)
50
100
75
25
Numbe r
of
Spreaders
4
3
4
2
Spreader
Shifts
Per Day
8
9
9
6
Days
Worked
Per Week
5
5
5
5
a /
 1967 Plywood and Board Products Directory
                               -19-

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  AVERAGE  GLUE WASTE FLOWS

            (PLANT  I)
               AVEKAM n0W.NOV.M-.MC 2, I2.t .PM.
DECEMBER
 1966
JANUARY FEBRUARY
 1967    1967
                  DATE
                                      FI6UME t

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the flow was determined.  This set up was used for 7 weeks and proved to




be the easiest to maintain.  Figure 3 shows the daily average flows




for the period.  The average flow for the 7 weeks was 24.4 gpm and




the average flow for the working days was 30.2 gpm.




          At Plant Number 3, a 60-degree V-notch weir and level




recorder were installed in a ditch located downstream from the




plant's settling tank.  This setup was used for 6 weeks and required




only minor maintenance.  Figure 4 shows the daily average flows for




the period.  The average flow for the period was 17.9 gpm and the




average flow for the working days was 21.6 gpm.




          At Plant Number 4, a 16-inch rectangular weir and level




recorder were installed in the last compartment of the plant's




settling tank.  This setup was used for 6 weeks.  Figure 5 shows




the daily average flows for the period.  The average flow for the




period was 53.2 gpm and the average flow for the working days was




54.0 gpm.




          Table 10 compiles the flow data for the four plants.  As




can be seen, the average flows vary widely.  This variance should




be a result of the spreader shifts per day and the types of glue




used.  Plant Number 4, with the fewest spreader shifts per day and




the highest percentage of exterior grade production, should have




the smallest flow but as can be seen it is much higher than the




other three.  At Plant Number 4 there is only a small difference




between amount of water used on working and nonworking days further




indicating water is being used when spreaders are not being washed




down.





                                  -21-

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DAILY AVERAGE GLUE  WASTE FLOWS
            (PLANT  2)
     *> tZ 24
     MAT IM7
2B 2B 3D t 4  
D B M   20 22 24 26 2B
  JUNE 1967
               DATE
                                  FIOUMC 3

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DAILY AVERAGE GLUE  WASTE  FLOWS
             (PLANT  3)
   AVCMAK njam,tucr S-JUM , irtuw.
    6 8
DBMMI8202224262B30
    MAY 1967
46 8 10 12 W
 JUNE 1967
                  DATE
                                     FIGURE 4

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DAILY AVERAGE GLUE WASTE FLOWS
           (PLANT 4)
            22 24 2B 24 30 2 4 6  K> tt M
               DATE
                               FMUHC a

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          The flow from Plant Number 1 was much lower than the




other three.  This may be due to the manner by which the flow was




calculated.  Here, actual amounts of water used for washdown were




measured, eliminating any other discharges which may get into the




waste stream further down the line such as the washdown water from




the glue mixing area.




          On two plants the daily maximum and minimum flows were




recorded.  The average is shown in Table 10.  These are shown as




a percentage of the average flow.  The maximum for the two plants




averaged 213 percent while the minimum was 60 percent.




          The average discharge for the four plants was 27.1 gpm.




This is about 39,000 gpd.  When multiplied by the 158 plants in




the study area, it results in a discharge of 6.2 million gallons




per day of glue waste.




          In conclusion, it can be seen that under present conditions




of inexpensive water and little concern over the destination and




pollutional effects of the waste, the flow from different plants




will vary markedly depending on plant practices.




          2.  Calculated Waste Discharges




          Two spreader washdowns have been observed.  Both of these




took place at Plant Number 1 where a water meter had been installed




in the wash-water line.  The first washdown required 210 gallons,




took approximately 35 minutes, and resulted in an average discharge




of 6 gpm.  The second washdown measured 250 gallons, took approxi-




mately 35 minutes, and resulted in an average discharge of 7 gpm.






                                  -26-

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For this calculation assume that 250 gallons at 7 gpm is needed to




wash down a spreader.  To flush out lines or troughs, an additional




10 minutes at 7 gpm is added, giving a total of 70 gallons for




flushing.  This gives a total of 320 gallons for each washdown.  The




average interior plywood plant with six spreader shifts and a wash-




down at the end of each shift would generate 1,920 gallons of waste




per day.  To this should be added the contribution from the washdown




of glue mixing equipment.  A plant making 10 batches of glue per




day and washing down their equipment after each batch should add




approximately 300-500 gpd of waste.  The total glue waste discharge




should then be around 2300 gpd per plant.  This is considerably less




than the 18,500 to 76,500 gallons measured at Plants 1-4.  This great




difference can be traced to the fact that water is allowed to run in




the waste lines when glue is not being washed off equipment.  This




practice has been followed for one or more of the following reasons.




First, some plant personnel feel that by diluting the glue waste their




pollution problems will be reduced.  Second, lines have become




plugged on occasion and water is kept running in an effort to prevent




this.  Third, forgetfulness and poor plant practices account for




the excess amounts of water consumed.




          It is concluded that glue waste discharges could and




should be reduced considerably.  This could easily be done through




better in-plant practices and through the development of new




techniques such as the use of steam instead of water for cleaning
                                  -27-

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the metal parts of equipment.  Surely, if a disposal method such




as incineration is to be used, the waste should be concentrated




as much as possible.




          The problem of plugged lines could possibly be solved




by using better line flushing techniques, minimizing waste line




lengths, by using teflon coated pipes or a combination of these.




If biological treatment is to be employed, some dilution of waste




beyond the quantities calculated may be needed to reduce the




effects of toxic substance on biological organisms.  This problem




will be studied further in connection with activated sludge pilot




plant work.




     B.  Waste Quality




          1.  Chemical Investigations




          Many different glue formulas are used by the plants in




the study area.  However, the glues vary only slightly with respect




to their actual ingredients.  Table 11 lists the ingredients of




typical interior and exterior glue mixes.  The pentachlorophenol




or phenolic formaldehyde resin listed under interior glue is added




only when a toxic mix is required.  This toxic mix makes the glue




more resistant to biological degradation.




          Because all glues could not be chemically analyzed,




typical exterior and interior glues were chosen.  These were


                     a/                                       a/
Borden's Cascophen 31  exterior glue and Borden's Casco S-230







a/
 Use of product and company names is for identification only and

  does not constitute endorsement by  the Department of the Interior.





                                  -28-

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                        TABLE 11

 Ingredients of Typical Exterior and Interior Glue Mixes


                        Exterior

              Water    .
              Furafil-7
              Wheat flour
              Phenolic formaldehyde resin
              Caustic soda
              Soda ash



                         Interior

              Water
              Dried blood
              Soya flour
              Lime
              Sodium silicate
              Caustic soda
              Formaldehyde doner for thickening
              Pentachlorophenolk/
              Phenolic formaldehyde resinH/
a/
Residue from furfural extraction of corn cobs and oat hulls

May be added to produce a toxic glue
                           -29-

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interior glue.  The Casco S-230 mix contains neither pentachloro-



phenol nor phenolic formaldehyde resin.   The ingredients of these



glues were obtained from the producing company and the glues were



mixed in the laboratory.  These prepared glues were then chemically



analyzed.  Table 12 lists the results of these analyses.  As can



be seen, the COD of the exterior glue is much greater than that of



the interior glue.  The levels of total phosphates and total



kjeldahl nitrogen, however, are much higher in the interior glue.



These low levels of phosphate and total kjeldahl nitrogen in the



exterior glues may make it necessary to add nutrients for biological



treatment.  The phenol concentration of the exterior glue is much



greater  than that of the interior glue.  While the phenol concen-



trations are quite high (514 mg/kg) they still are in the range of



500 mg/1 found by McKinney et al to be biologically treatable with



proper acclimation.' '



          2.  Biological Investigations



               a.   Stream Survey



               Biological investigations of a small creek in Western



Oregon were undertaken to determine the effects of plywood glue



wastes on the ecology of a small stream.  This creek receives both


                                                              a/
interior and exterior plywood glue wastes from Plant Number 1.



               Ten sampling stations were established on the creek.



The aquatic community is being sampled routinely through the
a/
~ Information regarding this plant can be found in Table 9.
                                   -30-

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                               TABLE 12

                   Chemical Analysis of Plywood Glue


Analysis and Units                     Exterior Glue   Interior  Glue

COD, mg/kg                               653,000           176,500

TOG, mg/kg                               176,000            52,000

Total Phosphate, mg/kg as P                  120               260

Total Kjeldahl Nitrogen, mg/kg as N        1,200            12,000

Phenols, ^g/kg                           514,000             1,810

Suspended Solids, mg/kg                   92,000            59,000

Dissolved Solids, mg/kg                  305,000           117,500

Total Solids, mg/kg                      397,000           176,500

Total Volatile Suspended Solids,  mg/kg    84,000            34,000

Total Volatile Solids, mg/kg             171,500           137,000
Borden's Cascophen 31 which is similar to Borden's  Cascophen  382
b/Borden's Casco S-230
                                  -31-

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collection of bottom-dwelling animals,  phytoplankton, and  attached




algae.  Artificial substrates for the collection of bottom animals




and diatoms were also installed and are being serviced  at  scheduled




intervals.




               Preliminary results from samples  that have  already




been collected indicate a classical picture of river pollution.   The




creek supports a well balanced community of aquatic organisms




upstream from the waste outfall and exhibits extremely  degraded




conditions downstream.  Pollution-tolerant organisms are in




abundance below the outfall along with large amounts of Sphaerotilus.




               Studies of this creek are valuable in showing dramatic




changes in the stream environment due to plywood glue wastes.  However,




the large volume of wastes and the normally low stream  flow coupled




with a marshy drainage area in the downstream reaches of the creek,




make it difficult to evaluate  recovery from the glue wastes.




               b.  Bioassays




               Toxicity bioassays run in accordance with Standard




Methods are being conducted to evaluate the relative acute toxicity




of plywood glue.  A series of bioassays, using guppies  as  test




organisms,  were conducted on both interior and exterior glues.  The




test solutions were renewed daily to lessen the effects of deoxy-




genation and detoxification.  Preliminary results indicate the




Cascophen 382, an exterior glue, is about four times as toxic as




Casco S-230, an interior glue.  Median tolerance limits for 96 hours




for Cascophen 382 ranged from 830 to 1200 mg/1 while Casco S-230




ranged from 4200 to 4800 mg/1.





                                  -32-

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                        VI.  DISPOSAL OF WASTE






     A.  Methods in Use




     Many different disposal methods for glue waste are being used




at the present time.  These methods vary from no treatment to systems




involving municipal treatment plants.  Table 13 lists 23 different




schemes used by the 106 plants surveyed.  As can be seen, 77 plants




employ some type of settling tank or pond.  The settling tanks




commonly consist of one or more 1,000-gallon septic tanks.  These




settling devices remove some of the glue solids and the wood chips.




Table 14 lists the chemical analyses of the settled effluent for three



                                           a/
of the plants used in the discharge survey."  Comparison of Table 12




and Table 14 shows a significant increase in the dissolved solids/




suspended solids ratio after the settling operation, indicating a




reduction of suspended solids.  A similar comparison also shows




little reduction in phenols, phosphates, and total kjeldahl nitrogen.




     The removal of suspended solids is further evidenced by the




filling of settling devices, necessitating their periodic clean out.




This clean out is needed every 1 to 3 months depending on the size




of the tank, number of washdowns, and types of glues used.  In these




tanks and ponds, lack of proper maintenance leads to poor efficiencies"




and subsequent problems.  Usually, these tanks are not cleaned until
a/
Information regarding the three plants can be found in Table 9.
                                  -33-

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                               TABLE 13
                 Disposal Methods of Plants in Survey
                                             Number of Plants  Using System
Disposal System

Field Spreading  .
Log Pond (N.O.)-
Log Pond, Field Spreading
Log Pond, S.L.R.O.k/
Municipal Sewer
Settling Pond (N.O.)
Settling Pond,
Settling Pond,
Settling Pond,
Settling Tank,
               Log Pond (N.O.)
               S.L.R.O.
               Waste Burner
               (Further Disposal Unknown)
Settling Tank, Field Spreading
Settling Tank, Log Pond (N.O.)
               Log Pond, Field  Spreading
               Log Pond, S.L.R.O
               Municipal Sewer
               Settling Pond (N.O.)
               Settling Pond, Field  Spreading
               Settling Pond, Slough
               Settling Pond, S.L.R.O.
               S.L.R.O.
               Waste Burner
Settling Tank,
Settling Tank,
Settling Tank,
Settling Tank,
Settling Tank,
Settling Tank,
Settling Tank,
Settling Tank,
Settling Tank,
S.L.R.O.
Other/
.3
c
M
O
M-l O
H J2
i-l Ctf
(8 T>
U H
1
1
1
1
1
1




2


1



1
1


2

Montana





1



2




1








Oregon
2


4
5
5
3
1
1
8
2
4
1
3
4

1

1
8
1
4
1
Washington




1
1

1

4
3
1



1



12
1
5

t i
a
0
H
3
1
1
5
7
8
3
2
1
14
7
5
1
4
5
1
1
1
2
20
2
11
1
a/
 Nonoverflow
k/Stream, Lake, River, or Ocean
/Waste is put in Drums and hauled to Land Disposal
                                  -34-

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                               TABLE 14

                 Chemical Analysis of Settled Effluent
Analysis & Units

PH

COD, mg/1

TOG, mg/1

Total Phosphate, mg/1

Total Kjeldahl

Phenol, |ig/l

Suspended Solids, mg/1

Dissolved Solids, mg/1

Total Solids, mg/1




mg/1
.trogen, mg/1

mg/1
mg/1
1
ispended Solids, mg/1
ilids, mg/1
#2 a/
Plant
11.6
1814
772
15
110
1667
148
1479
1627
125
1122
#3 y
Plant
9.4
1917
723
9
64
1790
356
1458
1814
338
1267
#4 y
Plant
10.8
1621
540
12
3
222
330
790
1120
322
919
'Average of 2 grab samples
2/Average of 3, 24-hour composite samples
/Average of 2, 24-hour composite samples
                                  -35-

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they are completely filled,  resulting in zero or even negative




efficiencies.




     Table 13 also shows that 18 plants employ some type of non-




overflow system to dispose of their waste.   In this type of system,




rates of evaporation and infiltration exceed the waste input.




Because of the plugging nature of glue solids, evaporation probably




accounts for most of the moisture lost.




     Twelve of the plants surveyed dispose  of their waste in munici-




pal treatment systems.   High pH plus wood chips and glue solids cause




some problems at these  plants.  Adjustment  of pH and the use of




settling tanks or ponds should make the waste amenable to conventional




waste treatment.  The settling tank would also help damp out any




slugs of toxic materials such as phenolic compounds which could




upset the balance of a  biological system.




     Eleven of the plants listed in Table 13 dispose of their  waste




without treatment of any sort.  The majority of these plants are




located on large bodies of water such as Puget Sound, the Pacific




Ocean, or the Columbia  River.




     B.  Incineration of Waste




     Due to the low volume of waste, the high organic content  of the




waste, and the availability of existing sources of heat, disposal




by incineration offers  a potential solution to the glue waste




problem.




     The survey of plants indicated that three plants at the present
                                  -36-

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time are using their waste burners to dispose of their glue waste.




Realizing that waste burners burn rather inefficiently and that




these metal "teepees" will be eliminated in the near future, some




other source of heat is needed.  One large corporation is consider-




ing the use of their Dutch ovens.  Most plants have this type of




device to generate heat.  These ovens burn at temperatures from




1800-2000 F.  If sander dust is burned, the temperature can go




as high as 2500F.




     An ash test was made on samples of interior and exterior glue.




These were run at the usual 600C (1112F) and at 1000C (1832F).




The results of these tests are shown in Table 15.  The tests




indicate that at 1000C (1832F) very little ash would remain.   The




interior glue produced 4.12 and 23.40 percent ash, based on wet




and dry weight, respectively, at 1000C (1832F).  The exterior




glue produced 6.12 and 15.76 percent ash,  based on the wet and




dry weight, respectively, at 1000C (1832F).  A plant with three




spreaders running six spreader shifts per day and washing down  each




shift would generate about 12 pounds of ash per day.  This is a




small percentage of the total ash produced in a furnace of this




type.




     The ash produced at 1000C (1832F) was tested to check




whether it could be redissolved.  A small  portion was redissolved




in H20 while the majority could not be redissolved with either  the




strongest acids or bases.
                                  -37-

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     One of the biggest problems in this method of disposal lies in




transporting the glue waste from the spreader to the furnace.




Maintenance of pumps and lines must be low.   This problem will be




investigated further as it will be important in many treatment




schemes.




     A third problem lies in a potential air pollution problem.




Before incineration can be an accepted method of disposal, it  must




be shown that no harmful pollutants are given off from the burning




of this waste.
                                  -39-

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                        VII.   PROPOSED STUDIES






     Future work on the project will be aimed at determining




applicable treatment methods  for plywood glue waste.   Investi-




gations will be made in regard to biological treatment,  floc-




culation, sedimentation, and  incineration.




     Biological treatment will be studied by installing  a mechanical




aerator at a plant and by using some bench scale activated sludge




units.  These studies will be made with and without the  use of




pH control and additional of  nutrients.  The work with the bench




scale units should give basic information on the treatability of




the waste including some insight into the effect of glue waste




on municipal treatment systems.




     Flocculation and sedimentation studies will be made at the




bench scale level.  These investigations will include the use of




flocculating agents such as alum, lime, ferric  chloride, etc.,




plus the addition of polyelectrolytes.  pH control will  also be




studied along with this phase of the project.




     More work will be carried out on the process of incineration.




This work will mainly concern problems associated with storage  and




handling of the waste from the time it leaves the spreader until




it reaches the furnace.  These problems could be acute as waste




streams to be treated must be highly concentrated.




     Water use and reuse will also be studied in conjunction with




the above-mentioned treatment schemes.






                                  -40-

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                      VIII.   SELECTED REFERENCES
1.   Sawyer,  Clair N.,  Chemistry for Sanitary Engineers, McGraw
         Hill,  New York,  1960.
2.   Anon.,  1967 Plywood and Board Products  Directory,  Forest
         Industries,  Portland,  Oregon,  1967.
                                 -41-

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IX. APPENDIX

-------
    APPENDIX A
DEFINITION OF TERMS

-------
                          DEFINITION OF TERMS






     COD -- Chemical Oxygen Demand.  A measure of the pollutional




strength of sewage and industrial wastes which is based on fact




that all organic compounds, with a few exceptions, can be oxidized




to carbon dioxide and water.  COD values give the amount of oxygen




required to perform this oxidation.




     Cold Deck -- A method of log storage where logs are stacked




in piles and kept wet to prevent checking by use of sprinklers




located on top of the stack.




     Conductivity -- Referred to as specific conductance at a




specified temperature (25C).  The opposite of resistance and




used as a measure of the concentration of total ionized solids




in water.  Reported in micromohos (nMHOS).




     Dissolved Solids  Solids which are in solution.




     Exterior Grade Plywood -- Plywood made with 100 percent




waterproof glue and a high grade veneer.




     gpm -- Gallons per minute.




     Green End  Portion of plant involving the storage and handling




of logs through the process of turning them into veneer.




     Interior Grade Plywood -- Plywood made with a moisture resistant




(but not waterproof) glue.




     ug/1 -- micrograms per liter (1000 (j.g/1 = 1 mg/1).




     mg/1 -- milligrams per liter (1000 mg/1 = 1 gm/1).
                                  -43-

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     mgd -- million gallons per day.



     p_H -- The negative log of the hydrogen ion concentration.   The



pH scale is usually represented as ranging from 0 to 14 with a  pH



of 7 representing neutrality.  Acid conditions increase as pH values



decrease and alkaline conditions increase as pH values increase.



     Phenols -- (C6H50H) The monohydroxy derivative of benzene,



known as carbolic acid.  Phenols are waste products of oil refineries,



coke plants, and some chemical producing facilities.  Phenols are



used extensively in the synthesis of phenolic type resins.  Concen-



tration of phenols in the order of .01 to .1 mg/1 are detectable by



taste and odor tests.



     Sphaerotilus sp. -- Slime-forming bacteria.



     Spreader Shift -- One spreader running one shift (8 hours).



     Suspended Solids -- Solids that either float on the surface



or are in suspension in water, sewage, or other liquids.


                                                                 a/
     TOG -- Total Organic Carbon.  TOG is determined on a Beckman



Carbonaceous Analyzer that catalytically oxidizes all organic



carbon to carbon dioxide that is measured with an infrared analyzer.



     Total Kjeldahl Nitrogen -- Organic nitrogen and nitrogen in



the form of ammonia (Nl^).  Does not include nitrogen in the form



of nitrates (N0) and nitrites (NO^)  Nitrogen and phosphorus



are nutrients necessary for maintaining biological growth.
'Use of product and company is for identification only and does

  not constitute endorsement by the U.  S.  Department of the Interior.
                                 -44-

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     Total Phosphate -- Phosphorus in organic and inorganic forms.




Phosphorus and nitrogen are nutrients necessary for maintaining




biological growth.




     Total Solids -- The sum of the suspended and dissolved solids,




     Total Volatile Solids -- The quantity of solids in water,




sewage, or other liquids lost on ignition of the total solids at




600C (1112F).




     Total Volatile Suspended Solids -- The quantity of solids  in




water, sewage, or other liquids lost on ignition of the suspended




matter at 600C (1112F).




     Veneer -- A thin sheet of wood turned off a log by a lathe




and used in the production of plywood.
                                 -45-

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      APPENDIX B






PLYWOOD PIANT LOCATIONS

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