EPA-R2-73-195
APRIL 1973 Environmental Protection Technology Series
Aerobic Secondary Treatment
of Plywood Glue Wastes
Office of Research and Monitoring
U.S. Environmental Protection Agency
Washington, D.C. 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were established to facilitate further
development < and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
U. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards.
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EPA-R2-73-195
April 1973
AEROBIC SECONDARY TREATMENT
OF PLYWOOD GLUE WASTES
By
John L. Graham
Project 12100 EZU
Project Officer
Dr. H. Kirk Willard
Pacific Northwest Environmental Research Laboratory
Corvallis, Oregon 97330
Prepared for
OFFICE OF RESEARCH AND MONITORING
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402
Price 90 cents domestic postpaid or 66 cents QPO Bookstore
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EPA REVIEW NOTICE
This report has been reviewed by the Environmental Protection
Agency and approved for publication. Approval does not
signify that the contents necessarily reflect the views and
policies of the Environmental Protection Agency, nor does
mention of trade names or commercial products constitute
endorsement or recommendation for use.
-11-
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ABSTRACT
An activated sludge treatment system, consisting of an aera-
tion tank, a tube-settler clarification module and a waste
solids lagoon, was constructed at Klamath Plywood Corpora-
tion in Klamath Falls, Oregon to treat urea-formaldehyde
glue and steam vat condensate wastewater. Operation of the
system was studied over a period of 18 months. Prior to
operation of the system, several in-plant^ changes were made
to reduce the flow and BOD loading. The flow to the treat-
ment system was reduced from about 40,000 gallons per day to
about 8,000 gallons per day and BOD from 500-1,100 pounds
per day to 100-400 pounds per day. During the period of
greatest efficiency, the flow averaged 6,700 gallons per day
and the BOD averaged 182 pounds per day. The results of the
study indicate that activated sludge treatment of urea-
formaldehyde glue waste alone is not feasible (average BOD
removal of 8 percent). The combined wastewater is amenable
to treatment by activated sludge, but requires the addition
of phosphorus. Without nutrient addition, the average BOD
removal was 38 percent. During the period when phosphorus
was added to the system, the BOD removal averaged 78 per-
cent. The flow averaged 9,800 gallons per day during the
latter period. Treatment.efficiency was adversely affected
by cold weather during part of the study period.
This report was submitted in fulfillment of Grant No. 12100
EZU under the partial sponsorship of the Office of Research
and Monitoring Environmental Protection Agency.
-111-
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CONTENTS
Section Page
I Conclusions 1
II Recommendations 3
III Introduction 5
IV Treatment Facilities 9
V Demonstration Procedures 15
VI Wastewater Characteristics 21
VII Treatment Plant Performance 27
VIII Project Costs 33
IX Discussion 35
X Acknowledgments 47
XI References 49
XII Abbreviations 51
XIII Appendixes 53
-iv-
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FIGURES
Page
1 Schematic Plan 10
2 Wastewater Characteristics - Phases I,
II and III 22
3 Wastewater Characteristics - Phase IV 23
4 BOD Removal and Effluent Characteristics
(3 Day Moving Average Data) 29
5 BOD Removal and Effluent Characteristics 30
6 BOD Removal Rate - Phase IV-2 37
7 Effect of Organic Loading on BOD
Removal - Phase IV 39
8 Temperature Effects (3 Day Moving Average
Data) 40
9 Temperature Effects - Phase IV 41
10 Oxygen Uptake 44
11 Fraction of BOD From Suspended Solids-
Phase IV-2 57
-v-
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TABLES
No. Page
1 Treatment System Design Criteria 11
2 Design Factors 12
3 Process Equipment 13
4 Demonstration Program Operation Schedule 17
5 Sampling and Testing Schedule - Phases I, II and
III 18
6 Sampling and Testing Schedule - Phase IV 19
7 Influent Characteristics - Phases I, II and
III 24
8 Influent and Effluent Data - Phase IV 25
9 Effluent Characteristics, Phases I, II and III 28
10 Influent and Aeration Basin pH Data -
Average Values 32
11 Treatment System Capital Cost 33
12 Demonstration, Operation and Maintenance Costs 34
13 Total Annual Cost 34
-vi-
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SECTION I
CONCLUSIONS
Operation of a completely mixed activated sludge system de-
signed to provide secondary treatment of glue and steam vat
condensate wastes at Klamath Plywood Corporation, has been
studied during the period from 15 February 1970 through 17
November 1972.
4
The following conclusions have been reached, based on the
results of the study presented in this report:
1. Activated sludge treatment of urea-formaldehyde
glue wastes alone is not feasible.
2. Combined glue and steam vat condensate wastewater
is phosphorus deficient and produces a poorly
settling activated sludge.
3. The combined wastewater is amenable to completely
mixed activated sludge treatment with the addition
of phosphorus.
4. Variations in MLSS levels had no significant effect
on BOD removal efficiency when treating the combined
waste without nutrient addition.
5. Foaming has little influence on operation of the
system.
6. Freezing of the aeration basin surface occurs dur-
ing cold weather periods.
7. The system has adequate buffering capacity so that
pH adjustment is not necessary.
8. The tube settler unit performed adequately during
periods when reasonably good settling activated
sludge was present.
9. The tube settler module anchorage was not adequate
to withstand the uplift force during periods when
the unit surface was frozen.
10. Substantial quantities of slowly degradable or non-
degradable solids accumulate in the system and are
carried out in the effluent flow.
-1-
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11. BOD removals from 55 to 95 percent can be achieved
with this type of system.
12. Treatment of these wastes by activated sludge
can be accomplished at a cost of $0.38 per thousand
BFM (Scribner C) of logs processed.
-2-
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SECTION II
RECOMMENDATIONS
Analysis of the data obtained during this study showed several
areas where further studies would be desirable.
No direct comparison of the tube settler performance with con-
ventional settling methods was made. Information of this type
would provide valuable criteria for design ^of future systems
of this kind.
Further analysis of the basin cooling problem and possible
solutions would be desirable.
A more comprehensive study of the nutrient requirements for
this type of waste would be valuable in view of the trend
toward more stringent effluent discharge standards.
The following items should be carefully considered in the
future evaluation of a biological system for treating glue and
steam vat condensate wastewaters:
o The application of primary settling prior to
the aeration basin. This concept results in a
solids handling problem; however, if sufficient
boiler capacity is available, the waste solids
could be disposed of by spraying on the hog fuel
prior to burning.
o The use of surge protection to reduce the
detrimental effect of large fluctuations in flow
to the activated sludge system.
-3-
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SECTION III
INTRODUCTION
SCOPE
A completely mixed activated sludge secondary treatment sys-
tem designed to treat wastes from the glue spreader operation
and condensate from the log holding vats was constructed at
Klamath Plywood Corporation in Klamath Palis, Oregon. The
system was studied through the periods from February 1970 to
April 1971, and June 1972 through November 1972, to establish
the feasibility of aerobic secondary treatment for this type
of waste. This project was financed with the aid of a
demonstration grant provided by the Environmental Protection
Agency (EPA), under grant number 12100 EZU.
The grant objectives were to:
1. Demonstrate the feasibility of secondary treatment
for glue waste, utilizing completely mixed acti-
vated sludge.
2. Determine the BOD removal efficiency and effluent
characteristics at various mixed liquor suspended
solids concentrations.
3. Determine the quality and character of excess bio-
logical sludge.
4. Define the influence of foaming, ice, and tempera-
ture on system operation.
5. Determine the effect of nutrient supplementation on
BOD removal efficiency and sludge settleability-
6. Determine the buffering capacity of the mixed
liquor, and the effect of pH adjustment on BOD re-
moval efficiency and sludge settleability.
->=?-
7. Determine the operating costs for the methods of
treatment demonstrated.
8. Evaluate the performance of the tube settler over-
flow system.
BACKGROUND
Klamath Plywood Corporation produces both interior hardwood
faced plywood and exterior plywood. Total production exceeds
7 million square feet per month (3/8" basis). About 2.2
million BFM of logs are processed each month.
-5-
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Nearly all face and back veneer is hardwood and is purchased,
dry and ready to lay up, from U.S., Canadian or Far East
sources. The core veneer is softwood (White Fir) and is
processed at the Klamath Plywood mill. Most of the product
is interior grade plywood utilizing urea-formaldehyde glue.
Only minor quantities of Melamine and phenolic exterior glues
are used.
Prior to beginning this project, from 20,000 to 60,000 gallons
per day of untreated glue spreader and log holding vat wastes
were being discharged to the Klamath River. A program to
correct this problem was initiated in March 1967, at the
direction of the Oregon State Department of Environmental
Quality (OSDEQ).
Klamath Plywood Corporation was directed to provide wastewater
treatment capable of 85 percent BOD removal prior to discharge
to the Klamath River.
The program developed included in-plant changes to reduce the
quantity of wastewater requiring treatment, and aerobic
biological treatment of the wastewater prior to discharge
to the river.
Two recycle systems were installed which reduced the waste-
water flow from an average of about 40,000 gallons per day
to about 8,000 gallons per day and the BOD load from 500-1,100
pounds per day to 100-400 pounds per day-
Glue Waste Recycle System. The glue spreader washdown water
is recycled and used for a portion of the glue make-up
water and replaces most of the fresh water previously used
for washdown. A small quantity of the concentrated urea-
formaldehyde glue washdown water is discharged to the treatment
system. Melamine and phenolic exterior glue wastes are
removed in a completely separate system and are trucked from
the mill site for disposal.
Vat Waste Recycle System. The debarked White Fir blocks
are heated in steam vats for several hours before peeling.
Water is added to the steam to provide a heat carrying medium.
A system was installed which provides for recycle of the
condensates from these vats to replace the fresh water which
was previously added to the steam. The excess condensates
are discharged to the treatment system.
Treatment System. The completely mixed activated sludge
process was selected for treatment of these wastes because
it appeared to be economically favorable and bench-scale
studies indicated a reasonable possibility of successful
operation.
-6-
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Klamath Plywood Corporation applied to EPA for a demonstration
grant to help finance the system because aerobic biological
treatment had not previously been used to treat this type
of waste. Construction of the facility was completed in
March 1970.
A complete list of definitions of the technical terms used
in this report may be found in the WPCF Glossary [1], and a
list of abbreviations and symbols used is contained in Section
XII.
THEORETICAL CONSIDERATIONS
Microbiology. The living organisms found in activated sludge
are classified as either plants or animals. The plants con-
sist of bacteria and fungi and the animals are primarily proto-
zoa, rotifers and nematodes.
Hawkes [2] stated that bacteria are normally dominant as pri-
mary feeders on organic wastes, with different holozoic pro-
tozoa being secondary feeders, and rotifers and nematodes are
found at the higher levels in the food chain. Fungi cannot
normally compete with bacteria, but they may predominate as
primary feeders if certain conditions exist, such as: low
pH, nitrogen deficiency, or low dissolved oxygen [3]. High
carbohydrate wastes are also reported to stimulate fungi
growth.
Metabolism. The metabolic reactions which occur within acti-
vated sludge can be divided into three phases: (1) oxidation,
(2) synthesis, and (3) endogenous respiration. These three-
phase reactions have been illustrated with general equations
formulated by Weston and Eckenfelder [4].
In the presence of enzymes, produced by living microorganisms,
about one-third of the organic matter removed is oxidized to
carbon dioxide and water, to provide energy for synthesis to
cell material of the other two-thirds of the organic matter
removed [5]. The cell material is also oxidized to carbon
dioxide, water, etc., by endogenous respiration (auto-oxida-
tion) .
Kinetics. Several authors [6,10,11] have formulated mathe-
matical equations for design and operation of complete-mix
activated sludge plants. Some of these formulations are more
easily used for evaluation of full-sized plant operation than
others. Eckenfelder's basic equations [11,12] are of this
nature and are presented below.
-7-
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BOD Removal. The microbial growth rate and steady-state sub-
strate removal in a completely mixed system can be defined by
use of the Michaelis-Menton relationship. A simplified equa-
tion for substrate removal was developed from this relation-
ship:
Sa ~ Sf Sr
Where: S = BOD removed, Ib/day
S = Influent BOD, Ib/day
a
S_ = Soluble effluent BOD, Ib/day
S = Soluble effluent BOD, mg/1
X = Average mixed liquor suspended
a solids
k = Removal rate coefficient (Ib
BOD/day/lb MLSS) per mg/1 BOD
NOTE: See Appendix A for further explanation.
The equation shows that BOD removal is proportional to the
product of the MLSS and the aeration time. However, the
validity of this equation is limited to conditions where the
actual substrate concentration is much less than the concen-
tration at one-half the maximum reaction rate (Michaelis
Constant) . A properly operating completely mixed system,
producing a low soluble effluent BOD would satis fythis condi-
tion since the effluent soluble BOD is the same as the soluble
BOD in the aeration basin. However, as effluent soluble BOD
approaches the concentration at one-half the maximum reaction
rate, BOD removal becomes less predictable by this simplified
form of the Michaelis-Menton kinetics.
-8-
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SECTION IV
TREATMENT FACILITIES
GENERAL DESCRIPTION
Fig-are 1 is a schematic plan of the treatment system showing
the flow pattern through the plant. Wastewater from washdown
of the glue spreaders flows by gravity through a screening
facility to the raw waste pump station.
Condensate collected from the log holding vats flows through
a screening facility into a holding tank which forms a portion
of the vat recycle system. Overflow from the holding tank
flows by gravity to the raw waste pump station.
The combined waste is pumped by a submersible sump pump through
a 3-inch diameter pressure line to the aeration basin inlet
box. The pump is controlled by means of a level sensing de-
vice in the sump.
The aeration basin inlet box serves two functions. It pro-
vides a location for sampling the raw waste and for flow
measurement. The wastewater flows out of the box over a 90
degree "V"-notch weir. The flow is measured, totalized and
recorded by means of a float-operated flowmeter.
Samples are pumped from the inlet box by a progressing cavity-
type pump which is controlled by a signal from the flow re-
corder. Composite samples, proportional to the flow into the
aeration basin are stored under refrigeration in a building
adjacent to the aeration basin. This building also houses
the electrical control panel.
The raw waste flow enters the aeration basin where two 10-
horsepower pump type, floating aerators provide oxygen for
biological growth, and mixing of the basin contents to maintain
the solids in suspension.
Effluent from the aeration basin flows upward through a tube
settler unit and overflows into a channel connected to the
outfall pipe. Solids settle in the tubes and are recirculated
into the basin contents.
Excess, or waste, solids are removed from the aeration basin
by pumping from a trough beneath the tube settler. These
waste solids are pumped to the solids storage pond where they
are concentrated by settling. Overflow from the pond is com-
bined with the tube settler effluent prior to discharge to the
river. The pond is also used, occasionally, as an effluent
polishing pond.
-9-
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FLOW MEASUREMENT
AND SAMPLING BOX
FLOATING
SURFACE
AERATORS
O
I
RAW WASTE
PUMP STATION
FROM GLUE
SPREADERS
LEGEND
© PUMP
-(S)- AUTOMATIC SAMPLING POINT
TS> OTHER SAMPLING POINTS
TUBE SETTLER
S> C
TUBE SETTLER
OVERFLOW
AERATION
' BASIN
FROM'STEAM
VATS
CONTROL PANEL AND
SAMPLE STORAGE t S> B
POND
^
OVERFLOW
SOLIDS STORAGE POND
FIGURE 1
SCHEMATIC PLAN
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DESIGN CRITERIA
Table 1 lists the criteria used for design of the Klamath
Plywood Corporation wastewater treatment system.
DESIGN FACTORS
The design factors used for the major unit and equipment selec-
tion are listed in Table 2. The manufacturers of the major
equipment items are listed in Table 3. The "treatment units
are described below.
The aeration basin has a volume of 80,000 gallons. This
volume provides a detention time at design flow (8,000 gal/day)
of 10 days. The basin was constructed as a tank with a steel
ring wall and a PVC liner. Oxygen is supplied to the basin
by two Ashbrook 10 horsepower, floating, pump type surface
aerators.
TABLE 1
TREATMENT SYSTEM DESIGN CRITERIA
Average Daily Flow (gpd)
Glue Waste 200
Vat Waste 7,800
Total 8,000
Peak Flow (gpm)
Glue Waste 5
Vat Waste 15
Total 20
Average Daily BOD Loading (Ib/day)
Glue Waste 30
Vat Waste 700
Total 730
Average Daily TSS Loading (Ib/day)
Glue Waste 12
Vat Waste 13_
Total 25
pH
Glue Waste 6-7
Vat Waste 5
Effluent Requirements 85% BOD Removal
-11-
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TABLE 2
DESIGN FACTORS
Raw Wastewater Pump
Number
Type
Capacity
Aeration Basin
Number
Volume
Detention Time
Design Organic Loading
Aeration Equipment
Number of Aerators
Type
Size
Clarification Unit
Number
Type
Area
Depth
Flow Measurement
Type
Waste Solids Pump
Number
Type
Capacity
Solids Storage Pond
Number
Type
Volume
Solids Detention Time
Submersible, nonclog
50 gpm
80,000 gal.
10 days @ design flow
68 Ib BOD/1,000
ft3/day
Floating, surface,
pump type
10 hp
Tube settler in
aeration basin
24 ft2
24 inches
Float operated, totalizing
recording
Progressing cavity
27 gpm
Earth embankment
40,000 ft3
2 years
-12-
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TABLE 3
PROCESS EQUIPMENT
Equipment Model
Raw Wastewater Pump SP 50A
Flowmeter TF-61-5M
Aerators MSA-10
Aeration Basin
Tube Settler
Waste Sludge Pump FS-56 C
Sample Pump FS-11 E
Manufacturer
Hydromatic Pump Co.
Leupold & Stevens
Instruments, Inc.
Ashbfook Corp.
Plasti-Steel, Inc.
Neptune MicroFLOC, Inc.
Robbins and Meyers, Inc.
Moyno Pump Division
The clarification unit consists of a tube settler module
mounted in the aeration basin. The unit was designed for an
overflow rate of 0.23 gpm per square foot of tube area at
average design flow. Sludge is recycled by the mixing action
of the tank contents. A portion of the settled solids which
accumulate beneath the tube settler are resuspended by this
action. A trough mounted beneath the module isolates a por-
tion of the solids so that they will become concentrated prior
to pumping to the waste solids pond.
The solids storage pond has a volume of about 40,000 ft . The
pond is of earth construction with a baffled, concrete over-
flow structure.
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SECTION V
DEMONSTRATION PROCEDURES
PLANT STARTUP
Startup of the plant was initiated on 17 February 1970. The
tank had previously been filled with water to test the opera-
tion of the aerators. About 3,500 gallons of raw wastewater
consisting only of glue spreader waste was pumped into the
aeration basin and the aerators were started. By the follow-
ing day, a substantial blanket of foam had developed on the
surface of the basin. The basin was seeded with approximately
150 gallons of solids taken from the river bank at the point
where the raw waste had previously been discharged to the
river. Approximately 1,500 gallons per day of raw waste was
added to the basin for a period of 10 days and total suspended
solids analyses were made on the mixed liquor to monitor the
buildup of biological solids. No apparent biological growth
occurred during this time. The raw wastewater pump was shut
off on 27 February and no wastewater was added to the system
through 5 March. An extremely heavy buildup of foam persisted
during this period.
On 9 March, 500 gallons of activated sludge from the Klamath
Falls airport sewage treatment plant was added to the aeration
basin as seed. Raw wastewater feed was again started and the
system was monitored through 30 March. The system did not
become acclimated during this period.
The decision was made at this time to restart the system. This
was accomplished by displacing the entire basin contents with
river water, reseeding with activated sludge, and adding glue
waste in controlled amounts such that the system would not be
overloaded. The system was operated in this fashion through
17 June.
During this time the system did not appear to acclimate proper-
ly, even though several oxygen uptake tests indicated that
biological activity was taking place. The biological solids
formed were of a dispersed nature and would not settle in the
tube settler.
Analysis of the test results and operating procedures produced
the conclusion that the system could not be efficiently oper-
ated with raw wastewater from the glue spreaders alone. The
decision was made at this point to begin running all of the
required tests, in order to document the failure of the system
to operate, and then proceed with the remainder of the demon-
stration program.
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OPERATION
The demonstration program was set up for three operation phases:
(1) operation on glue waste alone, (2) operation on glue and
vat waste without nutrient supplementation, and (3) operation
on glue and vat waste with nutrient supplementation. The
system was operated continuously, except for periods when the
mill was shut down, from 15 July 1970 to 4 April 1971 and the
operation was monitored throughout this period. The opera-
tion covered both cold and warm weather periods.
Table 4 lists the demonstration program operation schedule
which was established for this project. The development of
this schedule was based on the results of the pilot study
conducted by the FWPCA, which were summarized in an interim
report of October 1968 [7].
After completion of the scheduled three phases of operation,
a thorough analysis of the data was made. The results of
this analysis showed that further operation and data collec-
tion would be required to provide a complete report. A fourth
phase of operation was set up, to provide the required infor-
mation.
Phase IV consisted of operation on glue and vat waste with
nutrient supplementation, and was conducted in two parts.
Phase IV-1 covered the periods from 12 June 1972 through 24
June 1972 and 21 August 1972 through 11 September 1972. The
system was operated at a MLSS concentration of about 3000 mg/1
during this period. Phase IV-2 covered the period from 2 Oc-
tober 1972 through 17 November 1972, with the MLSS concentration
maintained at about 5000 mg/1.
SAMPLING SCHEDULE AND PROCEDURES
Samples were taken at various locations throughout the system.
These sample point locations are shown on Figure 1, and are
described below. Table 5 lists the sampling and testing sche-
dule used during Phases I, II and III. The sampling and test-
ing schedule for Phase IV is listed in Table 6.
Plant Influent. Automatic 24-hour composite samples, propor-
tional to plant flow, were obtained by pumping from the in-
fluent pressure line upstream from the aeration basin inlet
box. This location is shown as sample point A on Figure 1.
The automatic sampler, sample pump and storage refrigerator
are housed in a small building adjacent to the aeration basin,
which also contains the electrical control panel.
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TABLE 4
DEMONSTRATION PROGRAM OPERATION SCHEDULE
OPERATION
PERIOD
15 JULY 1970 -
15 SEPTEMBER 1970
16 SEPTEMBER 1970 -
23 NOVEMBER 1970
24 NOVEMBER 1970 -
4 JANUARY 1971
5 JANUARY 1971 -
11 JANUARY 1971
12 JANUARY 1971 -
3 FEBRUARY 1971
4 FEBRUARY 1971 -
9 FEBRUARY 1971
10 FEBRUARY 1971 -
8 MARCH 1971
9 MARCH 1971 -
22 MARCH 1971
23 MARCH 1971 -
3 APRIL 1971
PHASE
I
II
II
II
II
II
II
III
III
ITEM
-
1
2
3
4
5
6
1
2
METHOD OF OPERATION
GLUE WASTE ONLY - 4,000 mg/l
MLSS
GLUE AND VAT WASTE -
ACCLIMATION PERIOD
MLSS LESS THAN OPTIMUM'
(3,000 mg/l)
ADJUSTMENT PERIOD
OPTIMUM MLSS (4,000 mg/l) -
MINIMUM POWER REQUIREMENT
DETERMINATION
ADJUSTMENT PERIOD
MLSS GREATER THAN OPTIMUM
(6,000 mg/l)
GLUE AND VAT WASTE WITH
NUTRIENT SUPPLEMENTATION
ADJUSTMENT PERIOD
OPTIMUM MLSS (4,000 mg/l) -
MINIMUM POWER REQUIREMENT
DETERMINATION
AS DETERMINED BY THE PILOT STUDY (7).
-17-
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TABLE 5
SAMPLING AND TESTING SCHEDULE
PHASES I, II AND III
(NUMBER OF TESTS PER WEEK)
00
I
A
B
C
D
SAMPLE
POINT
PLANT INFLUENT
AERATION BASIN
TUBE SETTLER
EFFLUENT
WASTE SLUDGE
Q
8
3
-
3
1
O
O
00
3
-
3
1
SUSPENDED
SOLIDS
TOTAL
3
3
3
3
VOLATILE
3
3
3
LU
TEMPERATUR
3
2
-
-
a
3
2
-
1
DISSOLVED
OXYGEN
-
2
-
NITROGEN
TOTAL
1
1
-
AMMONIA
1
1
-
NITRATES
1
1
TOTAL
PHOSPHATES
1
-
1
-
DISSOLVED
PHOSPHATES
-
1
in
5
D
SLUDGE VOL
INDEX
3
-
SLUDGE AGE
2
-
ALKALINITY
-
1
-
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TABLE 6
SAMPLING AND TESTING SCHEDULE
PHASE IV
(NUMBER OF TESTS PER WEEK)
SAMPLE
POINT
A
B
C
PLANT INFLUENT
AERATION BASIN
TUBE SETTLER EFFLUENT
ID
O
o
m
6
6
6
O
LU
Q
^
LU
Q.
CO
TOTAL SL
SOLIDS
6
6
6
LU
CC
1
TEMPERA
6
6
6
a
6
6
6
O
DISSOLVE
OXYGEN
6
6
6
_l
I
^
Q
1
LU _^
TOTAL KJ
NITROGEr
1
1
1
CO
LU
TOTAL
PHOSPHA7
1
1
1
Aeration Basin. Grab samples were obtained from the surface
of the aeration basin. The location is shown as sample point
B.
Tube Settler Effluent. These samples were obtained by manually
compositing grab samples during the day shift. Sample point C
indicates the location of these samples.
Waste Sludge. Sample point D indicates the location of these
grab samples taken from the waste sludge discharge line.
ANALYTICAL METHODS
All analyses were performed in the Oregon Technical Institute
Laboratory in Klamath Falls, Oregon. All testing was done in
accordance with the FWPCA manual [8] or the twelfth edition
(1965) of "Standard Methods for the Examination of Water and
Wastewater" by the American Public Health Association[9].
-19-
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SECTION VI
WASTEWATER CHARACTERISTICS
GENERAL
The wastewater originates from two sources in the mill: the
glue spreader operation and the log holding, vats.
Glue Spreader Wastes. Excess glue is steam cleaned from the
spreader equipment during the washdown operation. The wash-
down water is recycled to the glue mixer, with the excess
being discharged to the treatment system. The wastewater also
contains excess glue from the hot press operation.
Log Holding Vat Wastes. After the barking operation and be-
fore peeling,the logs are placed in vats where they are
steamed for several hours. The steam condensate from these
vats is collected in channels and flows to a holding tank from
which the flow is recycled over the logs. Overflow from the
holding tank is discharged to the treatment system. This
wastewater contains wood sugars, dissolved lignins, tannins
and other constituents.
TREATMENT SYSTEM
Figures 2 and 3 are chronological plots of influent flow, BOD
and suspended solids data for the entire demonstration period.
These figures show that the flow to the treatment system was
highly variable and exceeded the design conditions much of the
time. The variability of the flow can be attributed to the
nature of the mill operation which causes intermittent dis-
charges of wastewater.
Maximum, minimum and average values of all Phase I, II, and
III influent data are listed in Table 7. These data are
separated according to the various phases of operation. Table
8 lists both influent and effluent data for Phase IV.
-21-
-------
I
to
NJ
I
t/3
OT
8
S3
o
o
<
o
g J
q <
i °
o
§
o
20
15-
ID-
S'
0-
20-
15-
10-
5-
0-
4-
3-
2-
1-
0
PHASE I
PHASE
PHASE III
1 2
JULY AUG. SEPT. OCT. NOV. DEC. JAN.
1970
FIGURE 2
WASTEWATER CHARACTERISTICS
PHASES I, II, AND III
FEB. MAR. APR.
1971
-------
I
to
u>
I
81
m
500
400-
300-
200-
~~ 100-
0-
_ 300-
< 200-
m 100-
0-
12-
10-
8-
6-
4-
2-
<
O
o
8
PHASE IV-1
-N
PHASE IV-2
i i
10 20
JUNE
20 31
AUG.
10
20
SEPT.
1972
30
10
20
OCT.
31
10
I
20
NOV.
FIGURE 3
WASTEWATER CHARACTERISTICS
PHASE IV
-------
TABLE 7
INFLUENT CHARACTERISTICS
PHASES I, II AND III
i
10
PARAMETER
FLOW (GAL/DAY)
COD (LB./DAY)
BOD (LB./DAY)
TSS (LB./DAY)
VSS (LB./DAY)
TEMP. (°C)
pH
TOTAL KJELDAHL
N (mg/l)
NH3-N (mg/l)
N03-N (mg/l)
TOTAL P (mg/l)
PHASE
AVG.
3,885
572
93
65
65
26.6
5.2
635
430
71
30
MAX.
19,000
1,605
562
356
352
37.8
6.9
650
450
75
31
MIN.
500
72
9
6
6
20.5
2.0
620
420
68
28
PHASE II-2
AVG.
7,675
522
387
384
372
32.4
4.6
600
413
63
23
MAX.
18,850
1,080
1,415
1,250
1,220
44.1
5.6
612
423
68
27
MIN.
800
68
30
23
23
18.1
3.6
590
410
58
20
PHASE II-4
AVG.
13,505
1,566
610
761
752
36.8
4.6
607
411
48
21
MAX.
19,400
5,885
2,131
2,235
2,220
50.2
5.1
610
415
60
21
MIN.
1,900
373
42
77
77
25.6
4.1
601
409
26
20
PHASE II-6
AVG.
15,810
790
172
280
272
36.8
4.6
596
404
26
20
MAX.
50,350
2,511
689
1,332
1,332
41.9
5.2
609
412
28
23
MIN.
4,150
191
39
39
32
32.0
4.3
589
400
25
19
PHASE 1 1 1-2
AVG.
15,030
780
181
193
193
31.2
4.5
588
399
24
19
MAX.
28,000
875
254
281
281
36.8
4.8
590
401
25
20
MIN.
8,650
586
116
68
68
25.0
4.3
586
397
23
18
-------
TABLE 8
INFLUENT AND EFFLUENT DATA
PHASE IV
to
en
PARAMETER
TEMPERATURE (°C)
PH
BOD5 (MG/L)
TSS (MG/L)
TOTAL PHOSPHATE
(MG/L)
TOTAL KJELDAHL N
(MG/L)
BOD REMOVAL (%)
ORGANIC LOADING
(LB BOD/LB MLSS)
FLOW (GAL/DAY)
PHASE IV-1
INFLUENT
AVG.
34
4.7
2450
1380
16.8
220
78.1
0.071
7610
MAX.
43
5.2
3980
3040
26.4
301
93.4
0.130
11,100
MIN.
26
4.5
1260
760
12.1
125
43.5
0.039
2240
EFFLUENT
AVG.
16
7.3
512
2110
21.0
285
MAX.
20
7.7
900
3200
24.2
356
MJN.
9
7.0
195
1580
14.1
197
PHASE IV-2
INFLUENT
AVG.
30
4.7
3250
1860
61.2
100
82.9
.058
6730
MAX.
41
5.2
6500
5720
262
160
95.0
0.118
12,200
MIN.
13
4.3
1279
500
9.4
25.0
54.6
0.022
3590
EFFLUENT
AVG.
12
7.1
459
1860
33.9
310.
MAX.
18
7.4
1090
4000
107
565
MIN.
6
6.6
100
250
8.8
6.0
-------
SECTION VII
TREATMENT PLANT PERFORMANCE
GENERAL
Influent and effluent COD, BOD and suspended solids and aera-
tion basin MLSS data were collected three times per week for
each of the first three phases of operation. Influent and
effluent BOD and suspended solids and MLSS data were collected
6 times per week during Phase IV. Additional data such as
temperature, pH, and nutrient levels, were recorded on a less
frequent basis. Table 9 lists average, maximum and minimum
values of the effluent data for Phases I, II and III. Effluent
data for Phase IV are listed in Table 8.
BOD REMOVAL AND EFFLUENT CHARACTERISTICS
Figure 4 is a chronological plot of plant flow, percent BOD
removal, aeration basin MLSS and effluent suspended solids
data for the first three phases of the demonstration period.
These curves were plotted as a three-day moving average of
the raw data. This approach results in a more meaningful
plot, showing longer range trends, since the data for these
Phases were extremely variable.
Figure 5 is a plot of the same parameters using Phase IV raw
data. These data were much less variable, hence three day
moving averages were not used.
Phase I. Operation of the system on glue waste alone resulted
in generally poor BOD removals. The maximum BOD removal dur-
ing this period was 27 percent, which occurred near the end
of the Phase I operation. BOD removals of less than 10 percent
were recorded throughout most of the period. The effective
detention time during this period was about 20 days, and the
average BOD load was about 13 percent of the design loading.
The center curves of Figure 4 show the aeration basin MLSS
data plotted on the same axes with the effluent suspended
solids data. The relative magnitude of these values serve
as an indication of the settleability of the activated sludge.
These values show that poorly settling biological sludge was
produced throughout the Phase I operation period.
Wastewater flow ranged from 500 to 19,000 gallons per day dur-
ing Phase I. For most of this period, the flow was uniform
on a daily basis, and averaged 3,900 gallons per day for
the entire period. However, substantial diurnal variation
in the flow rate was a common occurrence. These variations
in flow rate, coupled with the poor sludge settleability,
resulted in substantial solids carryover into the plant
effluent. This is reflected by the variation in effluent
suspended solids shown on Figure 4.
-27-
-------
TABLE 9
EFFLUENT CHARACTERISTICS
PHASES I, II AND III
PARAMETER
BOD REMOVAL (%)
COD (LB./DAY)
BOD (LB./DAY)
TSS (LB./DAY)
VSS (LB./DAY)
PH
TOTAL KJELDAHL
N (mg/l)
NH3 - N (mg/l)
N03 - N (mg/l)
TOTAL P (mg/l)
PHASE
AVG.
8
185
24
83
81
7.3
467
265
33
20
MAX.
27
527
39
365
362
8.0
480
278
39
22
MIN.
0
57
8
17
17
5.6
423
255
28
18
PHASE 1 1 -2
AVG.
56
321
64
221
221
7.0
405
276
35
22
MAX.
69
562
89
393
392
7.2
410
298
40
24
MIN.
46
61
14
32
32
6.8
405
255
30
22
PHASE II-4
AVG.
40
1142
590
533
515
6.6
408
288
26
16
MAX.
85
1718
2872
903
887
7.1
423
295
30
17
MIN.
0
660
95
301
265
6.0
401
278
19
15
PHASE II-6
AVG.
18
614
128
367
343
6.8
387
281
22
14
MAX.
49
2091
588
1134
1134
7.4
390
283
27
14
MIN.
0
251
33
153
150
6.4
381
279
19
13
PHASE III-2
AVG.
72
351
55
175
173
6.9
373
277
20
40
MAX.
86
616
91
276
276
7.0
375
280
21
40
MIN.
54
161
19
48
48
6.7
372
274
19
39
I
K>
00
-------
I
N)
ID
JULY
AUG.
SEPT. OCT.
1970
NOV.
FIGURE 4
DEC.
JAN.
FEB. MAR.
1971
APR.
BOD REMOVAL AND EFFLUENT CHARACTERISTICS
(3 DAY MOVING AVERAGE DATA)
-------
oo
o
I
100
I 60-
»
i 20.
0.
5-
. 4.
r
o-
12<
< 10'
! 8*
i j
CD o -
^^ o
9. 4
" 2
0
1
PHASE IV-1
YV-
t4f
^
MLSS
EFFL.S.S.
^
i
10
JUNE
i
20
20 31
AUG.
10
PHASE IV-2
i
20
SEPT.
1972
30
i
10
20
OCT.
31
FIGURE 5
BOD REMOVAL AND EFFLUENT CHARACTERISTICS
10 20
NOV.
-------
Phase II. The initiation of Phase II (operation on glue and
vat waste without nutrient supplementation) resulted in a
substantial increase in flow rate to the system. The flow
averaged 8,000 gallons per day during the acclimation period.
The Phase II operation period was accomplished in three parts
as discussed in a previous section and as shown on Figure 4.
The first part (Phase II-2) was to cover operation at a lower
MLSS level (3,000 mg/1) than the optimum. The average MLSS
level during this period was 4,000 mg/1. During the second
part of Phase II (II-4), the system was to be operated at the
optimum MLSS level (4,000 mg/1), and during the third part
(II-6), a higher than optimum MLSS level (6,000 mg/1). The
MLSS level averaged 4,500 mg/1 during II-4 and 4,000 mg/1
during II-6. The average BOD removal during these three periods
was as follows: II-2, 56 percent; II-4, 40 percent; and
II-6, 18 percent.
The biological sludge produced during the entire Phase II
operating period had poor settling characteristics resulting
in high effluent suspended solids. This is again indicated
by the data plotted on Figure 4.
Phase III. The effluent quality appeared to improve sub-
stantially during the Phase III operation period (operation
on glue and vat waste with nutrient supplementation.) The
addition of nutrients to the aeration tank in the form of a
phosphoric acid fertilizer (Simplot 0-20-0) caused a marked
improvement in the settleability of the activated sludge. The
data plotted on Figure 4 show a reduction in effluent suspended
solids with an increase in MLSS and a corresponding improvement
in BOD removal percentage after Phase III was begun. The
average BOD removal during this time was 72 percent.
The average flow during this period was 15,000 gallons per
day and the MLSS averaged 3,900 mg/1.
Phase IV. The performance of the treatment system improved
during the Phase IV operation period. The average BOD removal
during the period of operation at 3000 mg/1 MLSS was about
78%. The BOD removal increased to about 83 percent during
operation at 5000 mg/1 MLSS. However, as shown on Figure 5,
there was a significant variation in BOD removal throughout
the period.
Figure 5 also indicates a general trend toward reduced BOD
removals at higher flows. This is likely due to the reduction
in aeration time at higher flows.
There was also a substantial variation in effluent suspended
solids values through this period. However, the MLSS concen-
tration remained reasonably uniform.
-31-
-------
The flow to the treatment system averaged 7,610 gallons per
day during Phase IV-1 and 6,730 gallons per day during
Phase IV-2.
pH CONTROL AND SYSTEM BUFFERING
The system provided adequate buffering capacity throughout
the demonstration program. Influent and aeration basin pH
data are listed in Table 10 for each of the various operating
conditions. This data shows that the buffering capacity in
the aeration basin was sufficient to maintain a neutral pH,
with influent pH consistently in the 4 to 5 range.
TABLE 10
INFLUENT AND AERATION BASIN pH DATA - AVERAGE VALUES
PHASES
I II-2 II-4 II-6 IIT-2 IV-1 TV-2
Influent
Aeration
Basin
5.2
7.3
4.
7.
6
0
4.
6.
6
6
4.
6.
6
8
4.5
6.9
4.
7.
7
3
4.7
7.1
-32-
-------
SECTION VIII
PROJECT COSTS
The total capital cost for construction of the treatment
system was $40,370. A capital cost breakdown is listed in
Table 11. Table 12 lists demonstration, operation and main-
tenance costs for a 12-month operation period. The Research
and Development portion of these costs totaled $12,047. Oper-
ation and maintenance costs were $3,900 resulting in a total
of $15,947 for the 12-month period.
Table 13 lists the total annual cost of the system. These
figures include operation and maintenance costs and capital
cost amortized at 9 percent for 15 years. The operation and
maintenance costs were based on those recorded during the
Research and Development period and exclude costs related to
the demonstration program.
TABLE 11
TREATMENT SYSTEM CAPITAL COST
Item Total Cost
Vat Waste Holding Tank $ 675
Raw Waste Pump Station 2,327
Raw Waste Pressure Line 2,755
Sampling Equipment 1,470
Aeration Basin 6,912
Aeration Equipment 5,690
Tube Settler 2,829
Solids Storage Pond and Piping 5,738
Outfall Piping 509
Plant Piping and Valves 335
Electrical 4,055
Engineering 6,729
Legal and Administration 54
Contingency 243
Preliminary Site Engineering 49_
TOTAL CAPITAL COST $40,370
-33-
-------
TABLE 12
DEMONSTRATION, OPERATION AND MAINTENANCE COSTS
RESEARCH AND DEVELOPMENT
Item
Demonstration Program Supervision
Laboratory Testing (including Plant
Operation)
Sample Shipping
Final Report
Total Cost
$ 4,432
3,600
15
4,000
$12,047
OPERATION AND MAINTENANCE
Operation
Chemicals and Lab Equipment
Maintenance
Power
Office and Administrative
Subtotal
Included in
Lab Testing
$ 900
1,200
1,500
300
$ 3,900
TOTAL - DEMONSTRATION, OPERATION AND MAINTENANCE
COSTS
$15,947
NOTE: Costs based on operation from April 1970 to April 1971
TABLE 13
TOTAL ANNUAL COST
Item
Capital Cost
Amortized Capital Cost (9% - 15-yr)
Operation and Maintenance
TOTAL ANNUAL COST
Cost
$40,370
5,000
5,100
$10,100
-34-
-------
SECTION IX
DISCUSSION
ACTIVATED SLUDGE SYSTEM
General. Many limitations of completely mixed activated
sludge systems for treatment of this type of wastevrater were
encountered during the course of this project. The major
limitations were related to the type of waste, temperature
effects, nutrient deficiency, and the highly variable waste-
water flow. The extremely poor treatment results obtained
during Phase I indicate that aerobic biological treatment of
urea-formaldehyde glue waste alone is not feasible at this
location. Treatment efficiency improved considerably with
the addition of steam vat condensate to the system and reduc-
tion of the glue waste to a minimum flow. However, it appears
that phosphorus addition is necessary for this system to
successfully treat the combination wastewater.
Acclimation problems during startup of the system resulted
principally from the poor treatability of the waste and the
cold weather during this period. Biological reaction rates
are sharply reduced at low temperatures. The combination of
a slowly degrading waste and low reaction rates prevented a
normal startup of the system.
Treatment Efficiency. The low BOD removal efficiency observed
during Phase I was partially due to the poor settling charac-
teristics of the activated sludge. This problem was also
encountered during the pilot plant study [7]. The pilot
study also showed no apparent BOD removal increase by adding
nutrients.
Similar problems with sludge settling occurred during Phase
II. Low temperatures were also a problem during this period.
The changes in MLSS level and several oxygen uptake tests
showed the presence of biological activity in the basin but
poorly settling sludge was produced. This characteristic made
close control of the MLSS level very difficult because of the
washout of solids in the effluent during high flow periods.
Uncontrolled wasting of activated sludge was the result. The
design provided for MLSS control by wasting sludge at a rate
which could be preset on a timer controlling the waste sludge
pump. The MLSS levels shown in the planned operation sche-
dule for the various phases were not closely maintained be-
cause of the control problems described above. However, dur-
ing portions of these planned phases, the system was operated
at the MLSS levels indicated. Operation at these various MLSS
levels had no apparent effect on BOD removal efficiency or
effluent characteristics.
-35-
-------
BOD Removal. BOD removal in the activated sludge system as
discussed previously, is described by the equation
However, this simplified form of the Michaelis-Menton kinetics
is limited to use only where the substrate concentration in
the reactor is much less 1Jian the concentration at one-half
the maximum reaction rate. The concentration in the reactor
is the same as the effluent soluble BOD concentration in a
completely mixed system. This relationship was used to
evaluate the performance of the treatment system.
Data from Phase IV-2 only, were used for this analysis be-
cause the most consistent operation was achieved during this
period. Soluble BOD was not measured directly, but was
calculated from effluent total BOD and effluent total suspendec
solids data. This method is described in Appendix A.
Effluent soluble BOD varied from 20 to 300 mg/1 during Phase
IV-2, with an average of 140 mg/1. Eckenf elder ' s data [11]
for domestic sewage and certain industrial wastes, indicate
that effluent BOD values up to 80-90 mg/1 fall within the
required limits. Lawrence and McCarty [13] have shown the
one-half maximum reaction rate substrate concentration to be
highly variable. They show a variation of 65 to 355 mg/1,
based on BOD measurements, for various wastewater compositions
Eckenf elder ' s simplified equation for BOD removal, therefore,
appears to be of questionable validity for analysis of this
treatment system.
The BOD removal rate, k, is equal to the slope of the first
order curve passing through the origin, on a plot of total
pounds of BOD removed per day per pound of MLSS vs. mg/1 of
effluent soluble BOD. Figure 6 is such a plot, using the
data from Phase IV-2. This plot shows that the data is quite
scattered. This can be attributed to large fluctuations in
BOD loading to the system, as well as highly variable effluent
suspended solids concentrations which directly affected the
soluble BOD values in this analysis (see Figures 3 and 5) .
The curve shown on Figure 6 was drawn through the mean coor-
dinates of the data points because of the scattered data.
Figure 6 also shows that the BOD removal rate was very low.
This is due to the large accumulation of non-degradable, or
very slowly degradable, influent suspended solids in the
aeration tank. The use of "active mass" in the system, if
-36-
-------
111
SLOPE = K = 0.00035
100
200 300
EFFLUENT SOLUBLE BOD (MG/L
400
500
FIGURE 6
BOD REMOVAL RATE
PHASE IV-2
-------
such data were available, or possibly data for MLSS due to
BOD removed, to calculate the BOD removal rate, would likely
improve the reliability of the k rate obtained from this
type of plot. In general, it appears that the accumulation
of these biodegradably resistant solids tends to obscure the
kinetics evaluation. The BOD removal coefficient, k, result-
ing from this analysis was 0.00035 per day. This is much
lower than Eckenfelder's data [11] for various types of
wastewater. However, it must again be emphasized that this
method of analysis is of questionable validity because of
the marginal conditions encountered.
Figure 7 is a plot of percent BOD removal and organic loading
during Phase IV. In general, the BOD removal appeared to
increase with increasing organic loading, and to decrease
with decreasing organic loading. This indicates that the
average organic loading on the system was lower than that
required for the most efficient operation. Again, the accumu-
lation of poorly degrading influent solids in the aeration
basin resulted in calculated loadings which were probably
much lower than the actual loadings.
TEMPERATURE EFFECTS
Basin Temperature. Figure 8 shows aeration basin temperature,
air temperature, MLSS and percent BOD removal through the
first three phases of the demonstration period. This data
was plotted as a three-day moving average to show the trends
rather than daily variations, thus providing a better oppor-
tunity for data comparison. The aeration basin temperature
closely paralleled the air temperature nearly all the time.
Deviations from this pattern were caused by high influent
flows of vat waste, which raised the basin temperature for
short periods.
Temperature, BOD removal and MLSS data for Phase IV are
plotted on Figure 9. Raw data rather than three-day moving
averages, were plotted for this phase because the operation,
and the resulting data, were much more uniform than during
the first three phases. The most significant observation
from this figure is the apparent reduction in BOD removal
with lowering basin temperature, at the end of Phase IV-2.
No definite relationship between basin temperature and BOD
removal or MLSS level can be established from this data.
However, biological activity appears to have been retarded
by temperatures consistently below 10 degrees C.
Freezing Problems. The plant is located in an area subject
to extremely cold winter weather. A layer of ice formed on
the surface of the aeration basin on several occasions. This
caused a blockage of the tube settler effluent, effectively
-38-
-------
PHASE IV-1
-A/
PHASE IV-2
I
U)
vo
I
Q <
o >
co o
5
in
cc
,.
O 05
2 -J
100
80.
60-
40-
20
0
0.10
o <
-Q
< Q 0.05
a o
tr m
O m
i o
Vv-
10 20
JUNE
Ara
20 31
AUG.
10 20 30
SEPT.
1972
10 20 31 10 20
OCT. NOV.
FIGURE 7
EFFECT OF ORGANIC LOADING ON BOD REMOVAL
PHASE IV
-------
O
I
PHASE 1
1
PHASE II
2 bl 4
II
5
6
PHAS
1
E III
2
241
16
Is
-8
100-
80-
uj 60
Q 40-
20-
0
03
4H
3
s!
BASIN
'-YV
BASIN
«.ALA^
AIR
JULY AUG. SEPT. OCT. NOV. ' DEO ' JAISL FEB^ MAR. ^ APR.
1970 1971
FIGURE 8
TEMPERATURE EFFECTS
{3 DAY MOVING AVERAGE DATA)
-------
30
25
o
o
LLI ID
S
0
100
-. 80
£
§5 60
CO ^ 40
1 20
0
5
3 4
PHASE IV-1
I A/
PHASE IV-2
AIR
A/-
Y-V
^
10 20
JUNE
H\n
20 31
AUG.
AIR
10 20
SEPT.
1972
30
10 20
OCT.
31 10 20
NOV.
FIGURE 9
TEMPERATURE EFFECTS
PHASE IV
-------
stopping the plant operation. The uplift force beneath the
ice layer in the tube settler module lifted it from its
foundation twice.
Foaming. A layer of foam developed on the surface of the
aeration basin several times. No problems arose from the
presence of the foam. The worst condition occurred during
the startup period, when the foam layer spilled over onto
the ground around the basin.
However, this foam quickly dissipated. The foaming generally
occurred after a period when no wastewater was pumped through
the system, such as when the mill was down for several days.
Near the end of December 1970, the aeration basin contents
became very viscous and slimy. The reason for this condition
was not definitely established. However, it was very likely
due to a nutrient deficiency which affected the metabolism
of the microorganisms, a common occurrence for high strength
wastes with nutrient imbalance. The slimy condition dis-
appeared with the addition of phosphorus to the system at
the start of Phase III.
NUTRIENT EFFECTS
The pilot plant data indicated that the combined glue and vat
wastewater was deficient in phosphorus. The effect of nutrient
supplementation was determined during Phase III by adding 0.2
pounds of phosphorus, as Simplot 0-20-0 fertilizer, to the
system each week.
The BOD:N:P ratio was 100:15:0.5 during Phase II, before
nutrient addition was started. This ratio shows a low phos-
phorus content which would retard the biological growth.
With the addition of phosphorus during Phase III, the ratio
improved to 100:40:1.3.
Two principal effects of the nutrient addition were observed.
The viscosity of the mixed liquor returned to normal as the
slimy condition disappeared, and the settling properties of
the activated sludge improved markedly. The BOD removal
efficiency increased steadily until Phase III of the demon-
stration program was ended on 3 April 1971.
Visual observations after completion of Phase III indicated
the continuance of this trend. The improved settleability
of the activated sludge was corroborated by the steady re-
duction in effluent suspended solids during a period of widely
varying flow to the treatment system. During prior operation
phases, substantial washout of activated sludge solids occurred
-42-
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during periods of high flow. These observations led to the
initiation of Phase IV to obtain additional data.
The operation during Phase IV corroborated the visual obser-
vations made after Phase III was terminated. No problems
with increased viscosity of the mixed liquor were encountered
during this period. The BOD removal efficiency increased
slightly above that which was observed at the end of Phase
III. This level was maintained throughout Phase IV. The
effluent suspended solids stayed well below MLSS levels, but,
as shown on Figure 5, fluctuated widely.
Figure 5 and Table 8 show that the effluent suspended solids
concentration was very high throughout Phase IV. No definite
reason for this has been established. However, it could be
due to either the accumulation of poorly degradable, poorly
settling, influent solids or inadequate performance of the
tube settler module, or both.
TUBE SETTLER
A qualitative evaluation of the tube settler performance was
attempted. A definite conclusion about the effectiveness of
this unit was not reached. The unit appeared to do an ade-
quate job on the activated sludge with good settling proper-
ties. However, high solids carryover was observed with the
poorly settling sludge during periods of high flow to the
system. This problem may or may not be related to the effi-
ciency of the tube module since no comparison with conven-
tional methods of clarification was possible. Displacement
of the unit from its foundation due to ice buildup in the
module was a definite problem. However, this could be
avoided by using a different type enclosure. The high ef-
fluent suspended solids levels observed during Phase IV
would indicate a poor performance by the tube settler. The
average loading rate during this period was about 0.21 gal-
lons per *in per square foot of tube settler area. However,
this could not be substantiated with the data available.
OXYGEN UPTAKE
Figure 10 is a typical plot of oxygen uptake data taken dur-
ing Phase II. The actual uptake rate at this time was
19.2 mg/l/hr. An oxygen transfer rate of 35 Ib/hr at zero
D.O. and standard temperature (20 degrees C) was calculated
from this data. This results in an oxygen transfer efficiency
of 1.75 Ib/hp/hr based on the total aeration capacity of 20
horsepower. No correction for the alpha or beta factors was
made in these calculations.
-43-
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7.0 .
DATE: 7 OCTOBER 1970
TEMP: 8°C
do
dt = 19.2 mg/l/HR.
O2 TRANSFER = 1.75 LB./HP/HR.
10 15
TIME (MIN.)
20
25
FIGURE 10
OXYGEN UPTAKE
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SOLIDS STORAGE POND
Very little sludge was pumped to the storage pond during
the demonstration period because of the presence of poorly
settling sludge and the resultant difficulty in maintaining
the desired MLSS level. Most of the solids removed from
the system during this period were in the tube settler
effluent. However, during the period between the end of
Phase III and the beginning of Phase IV, the storage pond
was used as a polishing lagoon, with the entire effluent
passing through it prior to discharge to the river. This
approach has worked very well in terms of effluent quality,
and has been resumed since the end of Phase IV.
Prior to the initiation of Phase IV of the demonstration
program, the pond was drained. No solids concentration
data were obtained at that time, but the concentration was
estimated to be 8-9 percent solids. The estimated volume
of sludge in the lagoon was about 13,000 cubic feet. Several
truckloads of sludge were removed from the pond and spread
on farmland.
The pond was drained again at the end of the second year of
operation of the treatment system. The estimated volume
of sludge in the pond at that time was about 20,000 cubic
feet.
Since the end of the demonstration period the pond has been
used as a storage basin for a portion of the effluent during
the cold weather when the efficiency of the activated sludge
system is reduced. Sufficient capacity to allow this type
of operation is obtained by draining the pond during the warm
weather when the system efficiency is greatest.
No odor problems from solids storage have been observed. An
abundant algae growth has occurred on the pond surface during
the spring and summer months, which tends to reduce the odor
potential.
OPERATING PROBLEMS
Process. Most of the process operation problems have been
discussed in previous sections of this report. These problems
are summarized as follows:
Cold temperatures affected the process in two ways:
a reduction of the biological reaction rate; and
ice formation on the aeration basin and tube settler
surfaces. The poor treatability of glue waste alone
resulted in very poor BOD removal during Phase I.
The production of poorly settling activated sludge
was largely responsible for high effluent suspended
-45-
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solids concentrations and uncontrolled wasting of
solids from the aeration basin. The wide variation
in flow rate from day to day also added to this
problem.
Mechanical. There were very few major mechanical problems
during this demonstration program. Two items which were a
continual problem were the flowmeter and the automatic
sampler. A regular buildup of wood chips and other debris
beneath the float, hampered the operation of the flowmeter.
Several corrective methods, including a jet of water to Keep
these solids washed out, were tried with little success. A
similar plugging problem from chips and glue solids affected
the operation of the automatic sampler.
Plugging of the raw waste pump occurred during Phase I, but
with the addition of the vat waste to the system, this prob-
lem was lessened.
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SECTION X
ACKNOWLEDGMENTS
This project was supported in part by Environmental Protection
Agency Research and Development Grant No. 12100 EZU. Appre-
ciation is expressed to W. H. Ferry of Columbia Plywood
Corporation and to Dr. H. K. Willard, EPA project officer,
for their cooperation and assistance during this study.
-47-
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SECTION XI
REFERENCES
1. "Glossary: Water and Wastewater Control Engineering,"
APHA, ASCE, AWWA, WPCF, (1969).
2. Hawkes, H. A., "Ecology of Waste Water Treatment,"
Pergamon Press, New York, N. Y. (1963).
3. McKinney, R. E., "Microbiology for Sanitary Engineers,"
McGraw-Hill Book Co., New York, N. Y. (1962).
4. Weston, R. P., and Eckenfelder, W. W., "Application of
Biological Treatment to Industrial Wastes, I. Kinetics
and Equilibria of Oxidative Treatment." Sewage and
Industrial Wastes, 27, 802 (1955).
5. McKinney, R. E., "Biological Design of Waste Treatment
Plants." Presented at Kansas City Section of ASCE
Seminar, Kansas City, Mo. (1961).
6. McCarty, P. L., and Brodersen, C. F., "A Theory of
Extended Aeration Activated Sludge.", Jour. Water Poll.
Control Fed., 34, 1095 (1962).
7. Clark, B. D., "Pilot Plant Study on Aerobic Biological
Treatment of Urea Formaldehyde Glue and Steam Vat
Condensate Wastes," Interim Report, U. S. Dept. of the
Interior, FWPCA (1968).
8. FWPCA Methods for Chemical Analysis of Water and Wastes,
Federal Water Pollution Control Federation (1969).
9. Standard Methods for the Examination of Water and Waste-
water, APHA, AWWA, WPCF, New York, (1965).
10. McKinney, R. E., "Mathematics of Complete Mixing Activated
Sludge." Jour. San. Engr. Div., Proc. Amer. Soc. Civil
Engr., 88, SA3, 87 (May 1962).
11. Eckenf elder.- W. W. , "Comparative Biological Waste
Treatment Design." Jour. San Engr. Div., Proc. Amer.
Soc. Civil Engr., 93, SA6, 157 (December 1967).
12. Eckenfelder, W. W., "A Theory of Activated Sludge Design
for Sewage." Proceedings of Seminar at the University
of Michigan, 72 (February 1966).
13. Lawrence, A. W. and McCarty, P. L., "A Unified Basis
for Biological Treatment Design and Operation." Jour.
San. Engr. Div., Proc. Am. Soc. Civil Engr., 96, SA3,
757 (June 1970).
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SECTION XII
ABB1?EVIATIONS
mg/1 milligrams per liter
BOD biochemical oxygen demand
ffive day)
MLSS mixed liquor suspended
solids
mgd million gallons per day
TSS total suspended solids
D.O. dissolved oxygen
O_ oxygen
COD chemical oxygen demand
-51-
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SECTION XIII
APPENDIXES
APPENDIX A
SUPPLEMENTARY INFORMATION
-53-
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BOD REMOVAL RELATIONSHIP
Eckenfelder [11, 12] has presented the following formulation,
based on the Michaelis-Menton Kinetics, for defining micro-
bial growth rate and steady state substrate removal:
Where: S = BOD removed, mg/1
X = Average MLSS, mg/1
a
t = Aeration time, days
S^ = Soluble effluent BOD, mg/1
k = Removal rate coefficient,
(mg BOD/day/mg MLSS)/ mg/1 BOD
The application of BOD removal and MLSS data in terms of
Ib/day was more convenient for data analysis for this report,
Modification of the above equation was required to allow its
use with the desired units. This was accomplished through a
dimensional analysis of the equation.
Multiplying both numerator and denominator of the right side
of the equation by a volume term gives the following result:
Cone _ Cone Vol
Cone, x time Cone, x time Vol
_ Cone, x vol/time
Cone, x vol
Wt/time nv. Ib/day
"Iftl or Ib
-54-
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Therefore, the equation becomes:
Where: S = BOD removed, Ib/day
X= = Average MLSS, Ib
oi
S = Effluent Soluble BOD, mg/1
k - Removal rate coefficient, "* "" MLSS)
SOLUBLE BOD DETERMINATION
As indicated in Section IX, effluent soluble BOD measurements
were not made during this project. Effluent soluble BOD
values were approximated, however, as described in this sec-
tion, to provide data for the attempted evaluation of the
BOD removal rate coefficient. It must be kept clearly in mind
that these data are only approximations, and do not necessarily
represent the actual conditions prevailing in the treatment
system.
The effluent total BOD consists of two fractions: that BOD
contributed by the solids in the effluent flow; and that BOD
which is soluble.
The slope of the first order curve obtained by plotting eff-
luent BOD vs. effluent suspended solids, gives the fraction
of BOD contributed by a unit quantity of suspended solids.
Effluent soluble BOD is then obtained by use of the following
equation:
Se = st - y(xe)
Where: S = Effluent soluble BOD, mg/1
St = Effluent total BOD, mg/1
X = Effluent suspended solids, mg/1
y = Fraction of BOD per unit solids,
mg BOD/mg X
-55-
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Figure 11 is a plot of effluent total BOD vs. effluent
suspended solids for all Phase IV-2 data. The slope of
the curve (y) equals 0.17 mg BOD per mg suspended solids,
Therefore the above equation becomes:
S = S,. - 0.17X
e t e
This equation was used to calculate the effluent soluble
BOD data plotted on Figure 6.
-56-
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8
I
o
"1
a
n
w
5?
1,100-
1,000 -
900 -
800 -
c5 70°
5
9 600
LU
LU
500
400 -
300
200 -
100 -I
O
8
o o
1 000 2 000 3 000
EFFLUENT SUSPENDED SOLIDS (MG/L)
LOPE =Y = 0.17
4,000
5,000
FIGURE 11
FRACTION OF BOD FROM SUSPENDED SOLIDS
PHASE IV-2
-------
SELECTED WA TER '
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
2. 3. Accession No.
w
4. Title S. Report Date
Aerobic Secondary Treatment of Plywood Glue Wastes 6-
7. Autbor(s)
John L. Graham
9. Organization
CH2M/H111 (for)
Columbia Plywood Corporation
8. Performing Organization
Report No.
10. Project No.
11. Contract/Grant No.
12100 EZU
Portland, Oregon 13. Type of Report and
Period Covered
12. Sponsoring Organization
15. Supplementary Notes
Environmental Protection Agency report
number, EPA-R2-73-195, April 1973.
16. Abstract
An activated sludge treatment system, consisting of an aeration tank, a tube-settler clar-
ification module and a waste solids lagoon, was constructed at Klamath Plywood Corporatioi
Ln Klamath Falls, Oregon to treat urea-formaldehyde glue and steam vat condensate waste-
i/ater. Operation of the system was studied over a period of 18 months. Prior to operation
of the system, several in-plant changes were made to reduce the flow and BOD loading. The
Elow to the treatment system was reduced from about 40,000 gallons per day to about 8,000
gallons per day and BOD from 500-1,000 pounds per day to 100-400 pounds per day. During
the period of greatest efficiency, the flow averaged 6,700 gallons per day and the BOD
averaged 182 pounds per day. The results of the study indicate that activated sludge treal
ment of urea-formaldehyde glue waste alone is not feasible (average BOD removal of 8 per-
cent) . The combined wastewater is amenable to treatment by activated sludge, but requires
the addition of phosphorus. Without nutrient addition, the average BOD removal was 38 per-
cent. During the period when phosphorus was added to the system, the BOD removal averaged
78 percent. The flow averaged 9,800 gallons per day during the latter period. Treatment
efficiency was adversely affected by cold weather during part of the study period.
This report was submitted in fulfillment of Grant No. 12100 EZU under the partial sponsor-
ship of the Office of Research and Monitoring Environmental Protection Agency.
17 a. Descriptors
*Waste Treatment, Industrial Wastes, *Aerobic Treatment Activated Sludge,
Biological Treatment, Wood Wastes
17 b. Identifiers
*Plywood Glue Wastes, Tube Settler
17c.CO WRR Field & Group Q5D
21. No. of Send To:
Pages
18. Availability 19. Security Class.
{Report)
20. Security Class.
J. L. Graham (P*ge)
Abstractor \Iastitutioa CH2J$/HILIi, Corvallis, Oregon
22
WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON. O. C. 2O240
WRSIC102(REV JUNE 1971) SPO 913.261
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