Environmental Protection Technology Series
Activated Sludge Bio-Disc Treatment
of Distillery Wastewater
Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
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PEsi-r<;:;cB REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Aqency, have
been grouped into five series. These five bread
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
3ซ Ecological Research
^. 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.
EPA REVIEW NOTICE
This report has been reviewed by the Office of Research and
Development, EPA, 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.
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EPA-660/2-74-014
April 1974
ACTIVATED SLUDGE - BIO-DISC TREATMENT
OF DISTILLERY WASTEWATER
By
John L. Thomas and Lawrence G. Koehrsen
Project 12060 FLL
Program Element 1BB037
Project Officer
Max W. Cochrane
Environmental Protection Agency
Pacific Northwest Environmental Research Laboratory
Corvallfs, Oregon
Prepared for
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
For salo l)y tlio Superintendent of Documents, V.S. Government Printing Office, Washington, D.C. 20402 - Price $1.40
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ABSTRACT
Plant scale evaluation of activated sludge and Bio-Disc (rotating biologi-
cal contactor) treatment of distillery wastewater has been conducted over
a period of more than one year at Pekin, Illinois. The activated sludge
process consistently provided in excess of 90 percent removal of BOD-,
even at loadings greater than the treatment plant design levels. Waste
flow to the Bio-Disc process had to be reduced from the original design
basis of 120,000 gallons per day to ^5,000 gallons per day to attain a
BODj. removal efficiency of 90 percent.
After adjustment of design criteria based on test performance, investment
costs for a 530,000 gpd facility were determined to be $809,000 for the
activated sludge process and $980,000 for the rotating biological contactor.
Annual costs including fixed charges and operating costs were determined
to be $188,900 for the activated sludge process and $209,300 for the
rotating biological contactor.
The activated sludge process exhibited only a small reduction in BOD,.
removal efficiency when subjected to shock loadings of BOD,.. This same
performance could not be demonstrated with the rotating biological contactor
configuration used in this facility.
The activated sludge process demonstrated advantages over the rotating
biological contactor based on economics, treatment performance, and ability
to handle shock loads.
This report was submitted in fulfillment of Project No. 12060 FLL by
The American Distilling Company under the partial sponsorship of the
Environmental Protection Agency.
ii
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CONTENTS
ABSTRACT. . . .
LIST OF FIGURES
LIST OF TABLES.
SECTION I - CONCLUSIONS
SECTION II - RECOMMENDATIONS
SECTfON IK - INTRODUCTION
DISTILLERY PROCESS DESCRIPTION
POLLUTION ABATEMENT BACKGROUND
STUDY PURPOSE AND SCOPE
SECTION IV - TREATMENT PLANT DESCRIPTION .............. 7
DESIGN BASIS .......................... 7
DESIGN LOADINGS ........................ 9
PROCESS DESCRIPTION ...................... 10
DESIGN CRITERIA ........................ 16
Raw Waste Pumps ...................... 17
Grit Chamber ........................ 17
Nitrogen Addition ..................... 17
Phosphorus Addition .................... 17
Equal ization Basin ..................... 18
Bio-Disc .......................... 18
Final Clarifier Nos. 1, 2, and 3 .............. 18
Final Clarifier No. 4 ................... 19
Aeration Basins ...................... 19
Aerators .......................... 19
Sludge Pumps ........................ 19
SECTION V - WASTEWATER CHARACTERISTICS ............... 20
GENERAL ............................ 20
TOTAL ORGANIC LOAD ....................... 21
BODc:COD RELATIONSHIP ..................... 26
OTHER PARAMETERS ........................ 27
METERING, SAMPLING, AND TESTING ................ 27
SECTION VI - OPERATIONAL DATA AND EVALUATION ............ J>k
OPERATIONAL CHRONOLOGY AND RESULTS ............... 3^
Stage 1 - (September 27, 1971, to February 6, 1972 -
19 weeks) ........................ 36
Surface Aerators .................... 38
Nutrient Addition ................... 38
Grit Removal ...................... 39
Flow Rates ....................... ^0
ill
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CONTENTS (Continued)
Stage 2 (February 7 to February 20, 1972 - 2 weeks). ...
Stage 3 (February 21 to February 27, 1972 - 1 week). ...
Stage 3A (February 28 to March 12, 1972 - 2 weeks) ....
Stage k (March 13 to April 2, 1972 - 3 weeks) 46
Stage 5 (April 3 to April 16, 1972 - 2 weeks) 49
Stage 6 (April 17 to May 14, 1972-4 weeks) 50
Stage 7 (May 15 to June 18, 1972 - 5 weeks) 52
Stage 8 (June 19 to July 16, 1972 - 4 weeks) 54
Stage 9 (September 11 to October 1, 1972 - 3 weeks). ... 58
Stage 10 (October 2 to October 29, 1972 - 4 weeks) .... 59
Stage 11 (October 30 to November 26, 1972 - 4 weeks) ... 62
Stage 12 (December 4 to December 2k, 1972 - 3 weeks) ... 6k
WASTEWATER TREATMENT SUMMARY 67
SECTION VII - ADJUSTED DESIGN CRITERIA 69
BASIC CRITERIA 69
EQUALIZATION 69
KINETICS OF BOD REMOVAL 71
OXYGEN REQUIREMENTS 7k
SETTLING CHARACTERISTICS OF WASTE 75
ACTIVATED SLUDGE DESIGN CRITERIA 76
BIO-DISC DESIGN CRITERIA 78
RESPONSE TO SHOCK LOADINGS 79
SECTION VIII - ECONOMIC COMPARISON 82
ORIGINAL COST OF FACILITIES 82
General Construction Contract 82
Bio-Disc 82
Cool ing Tower 83
Engineering 83
ADJUSTED COST OF FACILITIES 83
Annual Costs 86
APPENDIX A - GLOSSARY 90
iv
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FIGURES
Figure Page
No. No.
TREATMENT PLANT SCHEMATIC,
2 PHOTOGRAPHS OF AERATION BASIN NO. 3 AND WASTE TREATMENT
PLANT 12
3 PHOTOGRAPHS OF BIO-DISC BIOLOGICAL MASS AND BIO-DISC .... 14
k PHOTOGRAPH OF INTERMEDIATE BIO-DISC CLARIFIER 15
5 RELATION OF RAW WASTE BOD5 TO GRAIN MASHED 22
6 BOD5 LOAD FREQUENCY - TREATMENT PLANT INFLUENT 2k
7 COD AND CORRESPONDING BODc - ACTIVATED SLUDGE PROCESS
INFLUENT 28
8 TEMPERATURE VARIATION - TREATMENT PLANT INFLUENT 29
9 PH VARIATION - TREATMENT PLANT INFLUENT 30
10 FLOW VARIATION - TREATMENT PLANT INFLUENT 31
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TABLES
Page
No.
1 WASTEWATER TESTING PROGRAM 33
2 BIO-DISC OPERATING PATTERN 35
3 ACTIVATED SLUDGE OPERATING PATTERN 36
4 DATA SUMMARY - STAGE 1 41
5 DATA SUMMARY - STAGE 2 43
6 DATA SUMMARY - STAGE 3 45
7 DATA SUMMARY - STAGE 3A 47
8 DATA SUMMARY - STAGE 4 48
9 DATA SUMMARY - STAGE 5 51
10 DATA SUMMARY - STAGE 6 53
11 DATA SUMMARY - STAGE 7 55
12 DATA SUMMARY - STAGE 8 56
13 DATA SUMMARY - STAGE 9 60
14 DATA SUMMARY - STAGE 10 61
15 DATA SUMMARY - STAGE 11 63
16 BOD DATA - SERIES OPERATION 65
17 DATA SUMMARY - STAGE 12 66
18 SUMMARY OF AVERAGE BIO-DISC PERFORMANCE DATA 67
19 SUMMARY OF AVERAGE ACTIVATED SLUDGE PERFORMANCE DATA . 68
20 ACTIVATED SLUDGE PROCESS - F/MLVSS AND RESULTING BOD
REMOVAL RATES '. 77
vi
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SECTION I - CONCLUSIONS
1. The American Distilling Company wastewater averages 860 mg/1 of BOD ,
is extremely variable in strength characteristics, and exhibits a
rapid oxygen uptake.
2. Evaluation of long-term records of treatment plant influent quality
indicates a correlation of BOD^COD as follows:
BOD = 0.786 COD - 35
where BOD and COD are expressed in pounds per day.
3. Total BOD in the distillery wastewater is dependent on factors other
than bushels of grain mashed. No valid correlation could be established
between raw material and wastewater BOD load.
A. The activated sludge process has consistently been successful in
removing over 90 percent of the BODj. influent to the treatment plant even
though such operating parameters as waste volume, waste strength, mixed
liquor solids concentrations, and dissolved oxygen levels have varied
over wide ranges.
5. The Bio-Disc process has achieved approximately 90 percent BOD^ removal
at flow rates of ^0,000 to 50,000 gallons per day when preceded by a
detention period in an aerated equalization basin of 10 to 12 hours.
6. Based on variation in the temperature and pH of the waste treated,
equalization storage must be provided ahead of the Bio-Disc treatment
line. The activated sludge process was not noticeably affected either
adversely or beneficially by the equalization pre-treatment.
7. Aeration is required in the Equalization Basin in order to maintain a
fresh wastewater amenable to treatment in the Bio-Disc process.
8. The activated sludge process as installed, is capable of handling more
flow and organic load than the original design basis.
9. The installed Bio-Disc unit cannot treat the specified wastewater load.
Operating results indicate the plant should be rated at ^5,000 gpd of
flow and 320 pounds per day of BODj..
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10. Comparisons of both capital costs and annual costs indicate that an
activated sludge system is less expensive than a Bio-Disc system for
treating a wastewater similar to that from The American Distilling
, Company plant.
11. Series operation with activated sludge treatment following the Bio-
Disc process did not yield any discernable advantage in terms of
improved treatment efficiency.
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SECTION II - RECOMMENDATIONS
1. An activated sludge system for treating wastewater with characteristics
similar to those of The American Distilling Company could be confidently
designed on the following basis:
F/M, BOD /MLVSS 0.30
MLVSS, mg/1 3,000
2. A Bio-Disc system for treating wastewater with characteristics similar
to those of The American Distilling Company should be designed with
aerated equalization storage ahead of the biological unit and with the
following maximum design loadings:
Hydraulic Loading, gpd/sq ft 1.0
Organic Loading, Ib BOD_/1,000 sq ft/day 1.2
3. Wastes with different characteristics, or subject to another pattern
of variation could substantially influence results of investigations
reported herein. Therefore, care must be exercised in extrapolating
design criteria developed in this research project to other situations.
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SECTION I I I - INTRODUCTION
DISTILLERY PROCESS DESCRIPTION
The research and development project reported herein was conducted entirely
at The American Distilling Company plant at Pekin, Illinois. The dis-
tillery operation utilizes approximately 12,500 bushels of grain per day
as the raw material. Grain use is about 70 percent corn, 20 percent rye,
and 10 percent malt. Industrial process operations include mashing, cooking,
fermenting, distilling, and by-product recovery for livestock feed production,
The initial process step consists of mixing ground grain with water and
cooking to produce a mash. The starch content of this mash is then
converted to sugar by a malt. The malted mash is fermented and the sugar
content is converted to alcohol. Alcohol is recovered from the mash in
a primary distillation column. Distillate from this first column is
again distilled in a pot still to refine the product. Mash remaining
after distillation is centrifuged and dried to produce a high protein
feed.
Process wastewater contains non-recoverable grain particles and by-products
such as organic acids, aldehydes, esters, and alcohols. Normal process
wastes are increased in flow and strength by the cleaning of grain mixers,
cookers, converters, mash coolers, fermenters, stills, centrifuges, and
evaporators. A substantial volume of wastewater originates at barometric
condensers in the by-product recovery operation.
POLLUTION ABATEMENT BACKGROUND
The American Distilling Company has been systematically working toward
solution of water pollution problems at the Pekin plant since 1967. The
first investigation, completed in that year, involved a water and waste-
water inventory and preparation of a report summarizing the problems and
outlining preliminary recommendations for sewer separation and treatment
faci1 it ies.
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Based upon the results of the initial inventory, sources of process and
sanitary waste discharges to 20 outfall sewers were identified. A sewer
separation program was undertaken to intercept contaminated waste flows
entering 11 of these sewers, leaving only clean streams which could be
discharged directly back to the Illinois River. Other uncontaminated
waters were intercepted before entering the waste sewers and redirected
to the clean water sewers. Flows from the sewers containing all of the
process and sanitary wastes were collected in an interceptor sewer dis-
charging to a new pumping station which was ultimately incorporated into
the treatment plant. Sanitary wastes are those produced by a plant staff
of 500 on the day shift and 15 on each cf the two other shifts.
High volume, slightly contaminated wastewater discharges from barometric
condensers with average BOD^ content of about 20 mg/1 were isolated and
combined in a separate trunk sewer for monitoring and direct discharge to the
river without treatment. Storm water was handled in a similar manner.
Beginning early in 1968 and continuing for approximately two years, exten-
sive laboratory scale biological studies were conducted by American Dis-
tilling personnel. These investigations evaluated the specific character-
istics of the wastewater in a biological (activated sludge) treatment
process, determined nutrient requirements for treatment, and provided
information relative to design of full-scale plant facilities.
In 1970, little technical literature information was available regarding
design and operation of full-scale wastewater treatment plants handling
distillery process wastes. The laboratory studies completed by The
American Distilling Company provided a substantial volume of information
on wastewater characteristics but also indicated a need for additional
research on this type of waste. A research and development program was,
therefore, formulated and submitted to the Environmental Protection Agency
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for plant scale evaluation of alternative biological wastewater treatment
processes. A grant offer was made to The American Distilling Company
on May 27, 1970, and was subsequently accepted.
Design of full-scale treatment facilities was initiated immediately and
the plant was completed and placed in operation on September 27, 1971-
This report covers the results obtained during the research operational
phase of the full-scale treatment facility. Twelve different operating
procedures were evaluated including both parallel and series operation
of activated sludge and rotating biological contactor processes.
After research operations were terminated, the plant continued to treat
wastewater from the industrial operation with discharge of treated
effluent to the Illinois River in compliance with current regulatory
criter ia.
STUDY PURPOSE AND SCOPE
The goals of the demonstration project reported herein are the evaluation,
on a plant scale basis of the performance of the rotating biological
contactor (interchangeably referred to as Bio-Disc) and activated sludge
processes for treating distillery wastewater.
Specific objectives of the project are to determine:
1. Operating characteristics of both types of systems under widely
varying conditions of temperature, pH, flow, and organic load.
2. Design parameters for industry-wide wastewater treatment process
selection and sizing.
3. Comparative treatment costs for the two types of systems.
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SECTION IV - TREATMENT PLANT DESCRIPTION
DESIGN BASIS
The design approach for treatment facilities was directed toward meeting
the following two requirements:
1. Reducing waste constituents to a level which would meet effluent
criteria regulations.
2. Generation of data to compare the economics and capabilities of
the activated sludge and the Bio-Disc processes.
Regulations covering effluent quality as set forth by the Sanitary Water
Board (Illinois) indicated an allowable BOD,, content of 30 mg/1 and a
suspended solids content of 35 mg/1. These were applicable to the total
waste flow including untreated flow from barometric condensers. On this
basis, BODj. removal of 90 percent for process wastes was planned. This
approach is illustrated as follows:
Barometric
Fl ow
Raw
, gpd
Waste BOD
Treated
Waste,
, Ib/day
mg/1
BOD5,
1
b/day
Process
530,
3,
mg/1
Waste
000
200
725
320
73
Condenser Flows
3,700,000
550
18
550
/'c
Total
*ป,230
3
18*
,000
,750
870
25
ow
"No treatment of this waste.
Sampling and gaging data indicated that the daily BOD,, load and daily fl
of process wastes would each exceed the values shown above approximately
20 percent of the time.
Prior to design, an assessment of waste treatablllty had been made In a
series of experiments performed by the technical staff of the American
"lauiinng Company. Typical data is shown for batch-type tests under
Experiment No*: "^ +-* ป reported in Volume !M Qf Laboratory Waste Treat-
ment experiments , which document! thiง prc'iminary laboratory work.
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In Experiment No. 20 the effect of aeration time on BOD5 (unflltered)
removal was checked for the activated sludge process. Five aeration
periods were examined ranging from 6 to 2k hours:
EXPERIMENT 20
Run No. J_ 2 3 4 5
Aeration Period, hrs. 2k 12 10 8 6
Influent BOD5> mg/1 644 702 563 434 683
Effluent BOD5, mg/1 17 33 13 8 2k
BOD5 Removal, % 97.k 95.3 97.7 98.2 96.5
Experiment 21 was performed to determine the effect of MLVSS level on
BOD removal:
EXPERIMENT 21
Rim 1-3 2-3 3-3 4-3
Raw Waste
BOD
MLVSS
After 4 hr Aeration
BOD
MLVSS
BOD Removal , %
After 8 hr Aeration
BOD
MLVSS
BOD Removal , %
After 24 hr Aeration
BOD
MLVSS
655
452
510
568
22.2
282
57.0
38
984
685
842
385
1 ,008
43.0
120
mr
82.5
8
1,604
675
1,652
176
1,742
73.5
42
93.8
6
2,000
680
3,326
64
3,662
90.4
14
97.9
5
3,882
BOD5 Removal, %' 94.2 98.8 99.1 99.3
Notes: 1. All BOD^ data on filtered samples.
2. All results in mg/1 except as noted.
8
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Data from Experiment 21 indicate that a higher MLVSS concentration does
increase BODj. removal with shorter aeration periods. However, with an
aeration period of 2k hours, MLVSS concentrations above 1,500 mg/1 do
not significantly affect BOD^ removal.
The above data indicated that treatability requirements (percent BOD^
removal) could be met for uniform strength waste treated on a laboratory
basis with an aeration period of between 4 and 8 hours. Other laboratory
tests demonstrated that supplemental nutrient requirements were approxi-
mately 1.5 pounds of nitrogen and 0.7 pounds of phosphorus per 100 pounds
of BODj-. Tests on suspended solids production indicated a range of values
from 0.16 to 0.35 pounds per pound of BODC in the raw waste.
>
Design criteria for the activated sludge process were established to
recognize variations in pH and temperature. An added requirement was
provision of sufficient storage capacity to maintain the process in a
viable state over the two-day weekend when it was anticipated that organic
loading and flows would be low. A higher solids retention time would also
have the latent benefit that endogenous respiration would proceed further
and reduce sludge production.
DESIGN LOADINGS
The loadings which were utilized as a design basis for the treatment plant
are as follows:
Flow Rate- 530,000 gpd--370 gpm
Peak Flow Rate 1,700,000 gpd1,200 gpm
BOD Load--- 3,200 Ib per day
Peak BOD Load k,"00 Ib per day
Suspended Solids Load 430 Ib per day
Maximum Suspended
Solids Load 1,350 Ib per day (during clean-up
operations)
Nutrient Addition 5 Ib nitrogen per 100 It BODr
Requirements , ,b phosphoruฃ per 10C Ib
"Exceeded 20 percent of time.
9
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PROCESS DESCRIPTION
Figure 1 is a plant flow schematic which illustrates the relationships
between the various treatment unit processes. Two photographs, showing
plant facilities are included on Figure 2. Following is an outline
description of the process flow pattern.
1. Waste is received at the pump station, metered, and discharged
to treatment facilities.
2. Nutrients, including nitrogen as a water solution of anhydrous
ammonia and phosphorus as a solution of triple superphosphate,
are mixed with the waste in the wet well.
3. Wastewater flows to a grit chamber where large particulate matter
i s removed.
k. Four secondary treatment lines are utilized including three for
activated sludge treatment (Lines 1, 2, and 3) and one Bio-Disc
process (Line k). Lines 3 and k are used to generate research
data with Lines 1 and 2 treating flow in excess of that required
by Lines 3 and k for test conditions.
5. Flow to the Bio-Disc passes through an equalization basin to
minimize short-term peak variations in pH, temperature, and
organic load. This unit also functions as a flow splitter to
divide waste flow among the four process treatment lines in the
desired proportion.
6. Influent to Aeration Basin No. 3 can be taken from the Equalization
Basin or directly from the grit chamber.
7. Piping is provided so that flow can be directed through the Bio-
Disc and Aeration Basin No. 3 in series.
8. Secondary clarification is provided for all lines. Sludge can
be recirculated to aeration basins or pumped to the sludge dis-
posal area.
10
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Treatment Plant Schematic
Figure 1
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CLARIFIERS
AERATION
BASINS
BIO-DISC
BUILDING
AERATION BASIN NO. 3
SLUDGE LAGOONS
WASTE TREATMENT PLANT
CONTROL
BUILDING
EQUALIZATION
BASIN
GRIT
CHAMBER
COOLING
TOWER
Figure 2
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9. Waste sludge is pumped to lagoons.
10. Total plant effluent is chlorinated prior to discharge to the
111inoi s River.
In the basic parallel flow sequence, as contemplated in the initial plant
design, a constant 25 percent of the plant design waste flow (133,000 gpd)
would be directed to the Bio-Disc unit and another 25 percent routed to
Aeration Basin No. 3. The balance of the waste flow would be treated in
Aeration Basin Nos. 1 and 2.
The Bio-Disc unit consists of a series of closely spaced discs mounted
on a horizontal shaft. Discs are submerged in the wastewater to just
below the shaft level in a tank with the bottom formed in a cylindrical
shape slightly larger than the discs. Rotation of the shaft alternately
exposes disc surface area to the wastewater and to the atmosphere. The
discs thus serve both as media for growth of a biological slime and as
an aeration device. Intermediate settling is provided between the second
and third stages of the six-stage Bio-Disc. Sludge removed at this point
is normally discharged to Aeration Basin No. 2 for further stabilization.
Flow from the final stage of the Bio-Disc is by gravity to a final clarifier.
Photographs of the Bio-Disc are shown on Figures 3 and 4.
Three identically sized aeration basins operating as complete mix activated
sludge units are provided for contact between the active microorganisms and
the waste materials. A photograph of Aeration Basin No. 3 is shown on
Figure 2. A separate final clarifier is provided for each aeration basin.
Sufficient underflow from the final clarifiers is returned to the aeration
basins to maintain the desired mixed liquor suspended solids content. Provi-
sion is made for up to 100 percent sludge return. The remaining sludge is
wasted. It is possible to return the sludge from Final Clarifier No. 3 to
Aeration Basin No. 3 independent of the operation of other basins and clari
fi ers.
13
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BIO-DISC BIOLOGICAL MASS
BIO-DISC
Figure 3
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INTERMEDIATE BIO-DISC CLARIFIER
Figure 4
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DESIGN CRITERIA
The activated sludge aeration basins and associated final clarifiers were
designed to provide 90 percent reduction of BOD,.. Aeration basins were
sized for a solids retention time of approximately 30 days at average flow
rates. This resulted in a 33-hour detention time at an average flow of
177,000 gpd and an average organic loading of 33 lb BOD^ per 1,000 cubic
feet per day. This is a somewhat longer detention period than requirements
indicated by laboratory tests performed under steady state conditions.
However, additional objectives of the design as established were to achieve
some measure of aerobic digestion and provide sufficient aeration basin volume
to dampen out the effect of the large hourly variations in wastewater flow,
temperature, pH, and strength. Maintaining a viable active mass over week-end
low load periods was particularly important. Data on variations experienced
are discussed later herein.
The design criteria necessary to adapt the Bio-Disc to this waste were more
difficult to project. This equipment with a multi-stage arrangement provides
a closer approach to a plug-flow biological process with each of the 6 stages
serving as a completely mixed reactor. It was reasoned that some equalization
would be required to minimize variation in influent waste temperature and pH.
It was reported that temperatures In excess of 85 F and pH values outside the
range of 6.0 to 8.5 would Impair process performance. Therefore, an equali-
zation basin with a detention time of about 9 hours at a flow of 120,000 gpd
was Incorporated In the treatment cycle. The Bio-Disc system was specified
to provide 90 percent reduction of BOD,, and suspended solids at an average
flow rate of 120,000 gpd and a BOD. loading of 800 lb per day. The hydraulic
capacity of the Bio-Disc Is somewhat less than 133,000 gpd (25 percent of total
plant capacity). This occurred because plant design flow criteria were Increased
based on added measurement data available subsequent to Bio-Disc purchase.
Specifications set forth performance requirements. The manufacturer was required
to establish detail design criteria. Equipment sizing resulted in an average
16
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Speed
(rpm)
1,150
860
860
Flow
(gpm)
1,200
k 00
580
Head
TftT
k2
33.5
35.5
organic loading of 17.8 Ib BOD5 per 1,000 sq ft of biological surface area and
an average hydraulic loading of 2.67 gpd per sq ft. The design organic loading
on the first stage is 69 Ib of BOD5 per 1,000 sq ft of biological surface.
A summary of design criteria and significant features of each of the major
units in the treatment system follows:
Raw Waste Pumps
1. Two identical 2-speed vertical centrifugal pumps provided.
2. Characteristics:
No. of Pumps
Running
1
1
2
Grit Chamber
1. Rectangular horizontal flow type with mechanical grit collection
equ ipment.
2. Design basis: horizontal velocity range, 0.75 to 1.20 feet per
second; overflow rate - ^0,000 gpd/sq ft.
Nitrogen Addition
1. Equipment: ammoniator to feed anhydrous ammonia in aqueous solu-
tion.
2. Maximum feed rate: 2^0 pounds per day as N.
Phosphorus Addition
1. Equipment: chemical solution tank with mixer to dissolve fertilizer
grade triple superphosphate pellets; variable speed chemical
metering pump to feed PO, solution.
2. Maximum feed rate: 71 pounds per day as P.
17
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Equal ization Bas in
1. Volume: 44,200 gallons.
2. Detention time: 8.9 hours at 120,000 gpd.
2.0 hours at 530,000 gpd.
Bio-Di sc
1. Number of stages: 6.
2. Discs:
Number: 154 in first two stages.
144 in other four stages.
298 total .
Size: 9.84 ft (3 meters) in diameter.
0.5 inch (13 mm) in thickness.
1-35 inches (34 mm) spacing.
Material: Expanded molded polystyrene.
3. Biological surface: 45,000 sq ft.
4 . Hyd raul ic 1oad ing:
Flow Load ing
(gpd) (gpd/sq ft)
120,000 (design) 2.67
530,000 (maximum) 11.8
5. Organic loading (design basis):
Total: 800 Ib BOD,, per day.
Average: 17.8 Ib BOD per 1,000 sq ft per day.
First Stage: 6g.O Ib EODq per 1,000 sq ft per day.
.>
Final Clarifier Nos. 1, 2, and 3
1. Hydraulic loading: 177,000 gpd each, 404 gpd per sq ft.
2. Normal detention time: 7-9 hours.
18
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F i na1 C1ar i f ier No. k
]. Hydraulic loading: 132,500 gpd , 580 gpd per sq ft.
2. Normal detention time: 3 hours.
Aeration Basins
1. Three equal size units provided.
2. Hydraulic loading: 177,000 gpd each (average); 567,000 gpd each
(peak f 1ow rate).
3. Volume: 2^4,000 gallons each.
k. Detention time: 33 hours at average flow rate.
5. Average organic loading: 1,070 pounds BOD per day each; 33
pounds BOD per 1,000 cu ft per day.
Ae r a to r s
1. Fixed pier surface aerators, two provided per basin.
2. Design specifications:
Size (each): 20 HP
Oxygen transfer: 3.2 Ib/hp-hr at 20 C in clean water.
2.0 Ib/hp-hr at 10 C in mixed liquor.
ซ = 0.8
3 = 0.9
Sludge Pumps
1. Three horizontal centrifugal pumps provided.
2. Capacity: 200 gpm each at 23 feet head.
3. Return sludge capability: 0 to 100 percent of design average
flow.
19
-------
SECTION V - WASTEWATER CHARACTERISTICS
GENERAL
Wastes generated by The American Distilling Company process operations
are typical of many industrial installations. Design bases and wastewater
treatment operational conditions are sensitive to numerous factors including
the follow!ng:
1. Substantial hour to hour, day to day, and longer term fluctuations
in total organic wastewater loads. An operation such as mashing
may occur two, three, or four days per week. Distilling may be
performed on other days while normal operation will, at times,
include both processes. Equipment cleaning also results in
periodic additions to the normal process waste streams. Fermenter
washing and pot still cleanout are typical of such operations.
2. Variations occur in pH, temperature, and flow volume. The pH of the
waste is increased periodically by the presence of alkaline
cleaning chemicals and has been observed to vary from a low of
5 to as high as 13- Large flows of condensate during periods of
evaporator operation significantly increase the total process
waste temperature with extremes of 50 F and 150 F experienced.
3. Reduced industrial processing on weekends results in extended
periods of low feed to biological systems.
Sampling, gaging, and quality analyses conducted as part of the initial
survey study indicated substantial flow, BOD, and suspended solids varia-
tions. Upon completion of the sewer separation program, a continuous
sampler was installed on the total combined process waste stream.
Composite sample data further substantiated the variation of the waste-
water characteristics and ultimately provided the basis for design loadings
to the wastewater treatment facilities.
20
-------
Compilation of data on raw waste was continued during the period of
treatment plant evaluation. This not only permitted determination of
plant performance, but also served as a basis for a more complete analysis
of of raw waste characteristics.
TOTAL ORGANIC LOAD
Treatment plant design was based on the original wastewater survey data
and on an anticipated grain mashing schedule of five days per week. Design
parameters were: a daily BOD load of 3,200 pounds exceeded 20 percent of
the time; and an average flow of 530,000 gallons exceeded 20 percent of the
time. The design load of 3,200 pounds of BOD per day and a flow of 530,000 gpd
results in a BOD concentration of about 725 mg/1.
An attempt was made to correlate wastewater BOD with bushels of grain
mashed. Because of changes in distillery operations from day to day. the
relationship was investigated for one week periods rather than single days.
Such one week periods include a normal recurring cycle of operations.
Data comparing bushels of grain mashed with total weekly wastewater BOD
are shown on Figure 5- Two curves are also presented v/ith equations as
follows:
Curve A: BOD = 0.256 B
Curve B: BOD = 7,982 + 0.177 B
Where
BOD = Weekly raw waste BODC, Ib.
B = Grain mashed weekly, bushels.
The equation for Curve A is derived from the design bases of 3,200 pounds
of BODj. and a daily grain mash of 12,500 bushels. This approach assumes
that BODj. produced is a direct function of grain mashed; however, it must
be recognized that during the study period there was no week when the
grain mashed averaged 12,500 bushels per day for all seven days.
21
-------
35
30
1 25
=>
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a.
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tn
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I 20
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LLJ
LU
5
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Relation Of Raw Waste BODs
To Grain Mashed
""'
^
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9
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^5s^
i^^
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0 10 20 30 W 50
GRAIN MASHED WEEKLY, THOUSANDS OF BUSHELS
Figure 5
22
-------
The equation for Curve B Is a least squares fit of actual data to establish
a linear relationship. It is concluded from the examination of data and
Curve B that BOD_ cannot relate directly to bushels of grain mashed.
Detailed Investigations to establish causes for the lack of correlation
between raw material and waste load were not within the scope of the study
reported herein. However, probable factors Include lack of consistency
in the amount of material wasted during cleanup operation, occasional dumps
of partially processed material, and similar items.
Figure 6 graphically depicts the frequency of dally BOD_ load occurrence.
For the period of November 1, 1971, through October 1, 1972, the daily
BOD,, load exceeded 3,200 pounds 2k percent of the time. During almost all
of this time, grain was being mashed only three days per week; there were
no weeks when grain was mashed five days, and only one when mashing occurred
four days.
Therefore, the treatment plant has been operating at or above the design
BOD,, load while the average raw material flow to the distillery has been
5 /
only about 60 percent of design levels. If grain mashing were performed
five days each week at a rate of 12,500 bushels per day, It is doubtful that
daily BOD,, loading would be any greater than currently experienced.
There have been several shock BOD,, loads to the plant. Two were parti-
cularly large; almost 7,600 pounds on March 13, 1972, and over 31,000 pounds
on July 12, 1972. The reactions of the activated sludge and Bio-Disc
treatment facilities to such loads are discussed in later sections of this
report.
23
-------
'10,000
9,000
8,000
7,000
6,000
5,000
>j 3,000
0
m
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- 2,000
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-^ 900
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200
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MM^MI
BO 05 Load Frequency
Treatment Plant Influent
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PERCENT OF THE TIME BOHg IS EQUAL TO OR LESS THAN VALUE
Figure 6
-------
Typical hourly variation of raw waste BOD is shown below:
TYPICAL BOD5 HOURLY VARIATION
Time
9 AM
10 AM
1 1 AM
12 PM
1 PM
2 PM
3 PM
4 PM
5 PM
6 PM
7 PM
8 PM
9 PM
10 PM
11 PM
12 AM
1 AM
2 AM
3 AM
4 AM
5 AM
6 AM
7 AM
8 AM
All results presented herein are based on a five-day operational week from
Monday through Friday unless otherwise noted. Weekend flows and BODj. loads
to the treatment plant have not been subjected to detailed study. However,
25
Monday
BOD5
(mg/1)
560
560
560
560
560
560
560
560
560
1 ,180
920
560
560
560
1 ,160
560
1,150
560
560
560
560
560
560
560
Thursday
BOD
(mg/1)
1 ,140
790
790
790
1,130
790
790
790
790
790
790
334
334
800
334
334
334
334
334
334
1 ,140
1 ,100
527
527
-------
a variation similar to that which occurs in the weekday loads has also been
observed in the weekend flows. During the period of March A, 1972, through
July 16, 1972, data for eighteen weekends was analyzed. BOD,, loads for the
two-day period varied from 395 to 5,925 pounds. During the period of
November 6, 1971, through July 15, 1972, flows for reported two-day weekends
ranged from 102,500 gallons to 703,000 gallons. Daily BOD load and flow
during weekends averaged 25 to 50 percent of the previous week daily values.
BOD5:COD RELATIONSHIP
The magnitude of the BOD load and the pattern of variation must be known
to control such operating factors as:
I. Nutrient add i tion.
2. F/M.
3. Aerator operating schedule.
The BOD,, test takes five days for completion. If the sample were a 2^-hour
composite, a period of six days can elapse between the receipt of the BODj-
load for treatment and the determination of its magnitude. Also, the BOD,.
test is recognized by various authorities as being subject to a great deal
of error. Precision and accuracy are both rather low, particularly for
high concentrations, where slight errors in dilution or seeding can be
multiplied by large factors.
At some waste treatment plants, the BODc concentration or weight per day is
relatively constant or varies with some regular pattern. At The American
Distilling Company plant, no such consistency or pattern has been observed.
Without any prior information as to magnitude of the likely BODc load for a
given day, the plant operator must set nutrient feed rates at arbitrarily
high levels so that enough nitrogen and phosphorus will be available during
times of high loads. This has led to an unnecessarily high concentration of
nitrogen and phosphorus in the effluent during days of low loads.
26
-------
A correlation between Influent BODj. and COD was sought in an effort to
correct this condition. The COD test is run in a few hours, and is more
precise and accurate than the BOD,, determinations. If a reasonable corre-
lation could be developed between BOD- and COD, then a treatment plant
operator would be able to utilize a COD test on a grab or short-term
composite sample of influent waste to obtain an idea of the magnitude of
load coming into the treatment plant. A BOD :COD relationship for the
raw waste entering Aeration Basin No. 3 is shown on Figure 7-
Fitted by a computer analysis to a linear equation form using the method
of least squares, the BOD :COD relationship in terms of pounds per day
shown on Figure 4 is as follows:
BOD = 0.786 COD - 35
OTHER PARAMETERS
Typical hourly variations in temperature, pH, and flow of raw waste are
shown on Figures 8, 9, and 10.
METERING, SAMPLING, AND TESTING
Points of routine metering and sampling within the wastewater treatment
process are shown on Figure 1 and are summarized on the following page.
The various flow streams are tabulated, along with the type of metering
element and the data the element generated.
27
-------
18
15
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COD And Corresponding BOD5
Activated Sludge Process Influent
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r
Temperature Variation
Treatment Plant Influent
i
Figure 8
-------
pH Variation
Treatment Plant Influent
6 DAY
30
-------
Flow Variation
Treatment Plant Influent
J.H9IN9
31
Figure 10
-------
Sampling
Point
A
Flow Stream
Raw Waste
B
C
D
E
F
G
Clari f ier
(Bio-Disc
eff 1 uent)
Clari f ier
(A.S.
eff 1 uent)
Return SI
Basin 3
Return SI
Basins 1
k
3
udge
udge
& 2
Waste Sludge
Combined
Plant
Effluent
Flow Data
Recorded
Indicated
I ndicated
Parameters
Continual ly
Mon i to red
pH, Temp.
Flow
None
None
Compos i te
Samples
Collected
Yes
Yes
Yes
Primary
Metering
Element
Palmer-Bowl us
Fl ume
PropelIer Type
Meter
PropelIer Type
Meter
Magnetic Flow
Meter
Magnetic Flow
Meter
Magnetic Flow
Meter
Palmer-Bowl us
Flume
Other sampling points where flow is not measured directly include the
following:
H Activated sludge mixed liquor.
I Third stage Bio-Disc effluent.
J r.larifier No. k influent.
S Effluent of Equalization Basin.
As shown on the preceding tabulation, composite samples were routinely col-
lected from four points (A, B, C, and G) for complete analysis. Tempera-
tures were continuously recorded at two of these four points (A and G)
while field checks were made, one each day, at the other two sampling
locations (B and C).
Indicated,
Total ized
I nd icated
Indicated,
Total i zed
Recorded,
Total i zed
Flow
Flow
Flow
Flow, Temp.
No
No
No
Yes
32
-------
Other tests were made on grab samples or manually composited samples, as
required. The schedule and frequency of tests is shown in Table 1.
Table 1
WASTEWATER TESTING PROGRAM
Number of Tests Per Week
Sampl ing Po int
Biochemical Oxygen Demand
Soluble BOD
Chemical Oxygen Demand
Soluble COD
Total Suspended Solids
Volatile Suspended Solids
Sol uble Sol i ds
pH
Temperature
Dissolved Oxygen
Nitrite-Nitrate Nitrogen
Kjeldahl Nitrogen
Ammonia Nitrogen
Total Phosphorus
Chlori ne
A
2
2
5
5
5
5
5
R*
R
-
2
2
2
2
B
2
2
5
5
5
5
5
5
5
1
2
2
2
2
~-
C D E
2
2 - -
5 - -
5 - -
5 5 5
5 5 5
5 - -
5 - -
5 - -
1
2 - -
2 - -
2 - -
2
_ _
F G H 1 J K
2-11-
______
1 - 1 1 -
------
5251 15
5-51 15
- 5 5 - - -
- 5511-
R 5 1 1 -
- - 511-
1 - - - -
1 - - - -
1 - - - -
1 - - - -
- 5 - - - -
*R Continuous recording.
All samples were analyzed
by plant personnel. All
12th edition of Standard
at The
analyses
Methods
Amer
ican Distil 1
were conducted
for
the Examinat
ing Company laboratory,
in accordance with the
ion of Water and
Wastewaters.
33
-------
SECTION VI - OPERATIONAL DATA AND EVALUATION
OPERATIONAL CHRONOLOGY AND RESULTS
To achieve the stated objectives of the research project, the study period
was divided into a series of stages, each with specific desired operational
characteristics. Plant operation was initiated on September 17, 1972.
During the period of study from September 27, 1971, to December 2A, 1972,
twelve operational stages were completed.
To analyze system operation a seven point approach was contemplated:
1. Start-up of facilities with growth and acclimation of the bio-mass
to establish a basic plant operational mode necessary to achieve
90 percent removal of BOD^.
2. At a constant flow of 133,000 gpd through the activated sludge
process, determine the effect of varying MLSS and/or MLVSS.
3. Vary the flow through the Bio-Disc and activated sludge processes
to determine effect of BOD_ removal. Hold MLSS concentration
in aeration basin at previously determined optimum level.
^4. Operate the Bio-Disc and activated sludge processes at optimum flow
level to obtain 90 percent BOD_ removal. Maintain MLSS at optimum
level. ~"
5. Vary the detention time of waste in Equalization Basin to determine
any effects of pH and temperature on the biological process In
either the Blo-DIsc or activated sludge system.
6. Operate the Bio-Disc and activated sludge processes In series at
several flow levels to determine performance with this operating
mode.
7. If time permits, vary nutrient levels to establish optimum levels.
Detail planning of operating parameters for individual stages changed through-
out the investigation as results of performance of previous stages were evalu-
ated. A summary of planned and actual operating conditions provides an over-
view of conditions prior to a detailed discussion of each stage. This data
is shown in Tables 2 and 3.
-------
TABLE 2
BIO-DISC OPERATING PATTERN
Flow
(1,000 gpd)
Stage Planned Actual
(Average)
1 - 57
2 60 63
3 60 69
3A 45 45
4 45 49
5 45 45
6 45 48
'7 45 45
8 90 71
9 130 114
10 65 55
11 72 65
12 265 224
After an initial attempt In Stage 1 to treat waste with the Bio-Disc at a
flow rate of 133,000 gpd without acceptable performance, the rate was
decreased to 60,000 gpd then to 45,000 gpd. Aeration of the Equalization
Basin was initiated at the start of Stage 7. In subsequent stages flow
was increased to determine if such aeration would provide better per-
formance. The high flow rate in Stage 12 was established to determine
performance of series operation with the activated sludge process.
For the activated sludge process, it was planned to maintain a constant
flow through Stage 5 and increase the MLSS (and MLVSS) to determine
optimum concentration. In subsequent stages, the flow was first decreased
then later increased to determine the effect on process performance. At
higher flows it was anticipated that BODr removal would decrease to the
90 percent level.
35
-------
TABLE 3
ACTIVATED SLUDGE OPERATING PATTERN
Flow
MLSS
MLVSS
Stage
1
2
3
3A
4
5
6
7
8
9
10
11
12
(1 ,000
PI anned
133
133
133
133
133
80
45
90
130
185
212
265
gpd)
Actual
(Average)
92
135
156
123
114
148
79
50
78
118
170
195
224
(mg/1)
Planned
--
1,250
2,500
3,500
3,500
4,500
4,500
4,000
4,500
4,500
4,000
4,000
4,000
Actual
(Average)
--
2,500
2,198
3,615
4,294
3,661
3,958
4,208
4,237
4,860
4,025
--
(mg/1)
Actual
(Average)
2,470
1,471
2,187
1,929
3,060
3,610
3,105
3,350
3,649
3,488
4,053
3,475
2,721
Stage 1 (September 27, 1971, to February 6, 1972 - 19 weeks)
The purpose of this stage was to establish an acclimated biological environ-
ment for both the activated sludge and Bio-Disc processes. Seeding was
performed with activated sludge containing a suspended solids content of
10,500 mg/1 obtained from the Greater Peoria Sanitary District. The aeration
basins received 1,950 gallons and the Bio-Disc received 650 gallons of this
material. To aid in acclimation, flow was sent to treatment facilities for
only 8 to 15 hours per day for the first two weeks. In addition, it was
planned that this stage would provide an opportunity to determine and to
correct any start-up mechanical or operating problems.
-------
Initial planning contemplated a flow of 133,000 gpd (25 percent of total
plant design flow) to the activated sludge process (Aeration Basin No. 3)
and the same flow to the Bio-Disc. Flows to both processes were routed
through the Equalization Basin on the basis that both should receive waste
with the same characteristics.
By early November, it became apparent that the Bio-Disc could not treat
waste flows of this magnitude and achieve 90 percent BODj. removal without
some modifications to operating conditions. Flows to the unit were reduced
to about 50,000 gpd after November 14 and various problems in the operating
environment were considered. These included the following:
1. pH variation.
2. Temperature variation.
3. Zero dissolved oxygen in waste from Equalization Basin.
The pH of the incoming raw waste varied from less than 5-0 to greater than
10.0. This was measured by a continuous recorder. The ability of the
Equalization Basin to minimize this range had not been established. There-
fore, grab samples of waste entering the Bio-Disc were checked periodically
during December, 1971. Although a variation from 6.4 to 9-9 was noted by
test, it was assumed that a wider range probably had been experienced.
Likewise, raw waste temperature exceeded 140 F at times, but intermittent
temperature readings at the Bio-Disc did not exceed 91 F.
Although the dissolved oxygen of the waste entering the Bio-Disc was zero,
it was assumed at that time that high pH and high temperature were the
major factors responsible for poor performance. On January 11, the flow
pattern was changed to reduce the effect of sudden peaks in raw waste
temperature and pH. Flow to the activated sludge process was routed to by-
pass the Equalization Basin. Only flow to the Bio-Disc was routed through
the Equalization Basin. This effectively increased the equalization period ai
37
-------
therefore, should have minimized pH and temperature reduction. However,
this longer detention period produced a septic waste in the Equalization
Basin. BOD^ removal rates through the Bio-Disc process improved after
January 11 (61.6 percent during the week of January 10 to 90.2 percent
during the week of January 31). On January 3'> to alleviate the septic waste
problem, the detention time of the basin was again shortened by routing
part of the flow to the activated sludge process through the Equalization
Basin. It was not possible to determine the division of flow but it was
estimated that approximately one-half the flow through the Equalization
Basin went to the Bio-Disc. The Equalization Basin was cleaned in early
February, but septic conditions quickly reappeared. Contents removed were
black solids including some grain particles and carbon.
The activated sludge process, represented by Aeration Basin No. 3 and
Final Clarifier No. 3, displayed the capability of removing greater than
90 percent of the influent BOD during this stage. Operations were
hampered by recurring difficulties with the stationary aerators.
The following is a summary discussion of start-up adjustments and opera-
tional problems which were recognized and dealt with during the early phases
of the investigations:
Surface Aerators - The pier-mounted surface aerators required numerous
mechanical modifications. These units exhibited excessive vibrations
due to lack of dynamic balance. This caused mechanical failure. In
November, the pier-mounted aerators were replaced by temporary floating
units while repairs were made to the original equipment. The pier-
mounted aerators were all operating again by February k.
Nutrient Addition - Nitrogen and phosphorus were added to the waste-
water to provide necessary nutrients for biological growth. The planned
nitrogen and phosphorus additions were 5 percent and 1 percent of the
raw wastewater BOD,, content, respectively. To meet this requirement,
anhydrous ammonia was injected as a water solution to provide nitrogen
and triple superphosphate was added to provide phosphorus.
38
-------
Both nutrient supply systems developed problems with plugging of
supply piping. This was solved in the phosphate system by:
1. Mixer modification in the supply tank to provide better dispersion
of the sparingly soluble triple superphosphate.
2. Screening of the phosphate suspension prior to pumping (30 mesh
screen).
3. Use of supplemental carriage water (well water) to dilute the
phosphate suspension.
The nitrogen system originally relied upon untreated well water as a
carrier of the ammonia nitrogen to the pump station wet well. The high
pH of the ammonia solution resulted in precipitation of calcium
carbonate and possibly some magnesium hydroxide. Scale formations
completely plugged the ejector in only a few hours. This problem
was minimized by substituting mixed liquor from Aeration Basin No. 2
for the well water as the carriage liquid.
Grit Removal - The amount of material removed in the grit chamber far
surpassed original design estimates. It was anticipated that the
quantity of grit including inorganic materials such as sand and cinders
would be only a few cubic feet per day. However, presence of other
materials such as whole and broken grain kernels increased the amount
of readily settleable materials. Carryover of some of this material
settled in the flow splitter channels of the Equalization Basin.
Therefore, velocity in the grit chamber was reduced approximately 75 per-
cent to 0.25 to 0.30 feet per second by adjustment of weir level.
Resulting material removed in the grit chamber increased to a level of
2 to 3 cubic yards per week. This necessitated construction of a chute
to transport the materials to the ground to replace the original receiving
container. Some freezing of the moist solids in the grit chute has been
experienced.
39
-------
Flow Rates - With a varying raw waste influent flow, adequate wet
well equalizing storage must be available to maintain a minimum
continuous flow to treatment facilities. In this instance equalizing
storage with one pump operation is less than 1,000 gallons. Since the
wet well was constructed prior to the gaging period which established
flow characteristics, sufficient equalizing capacity has not been
available to maintain a continuous flow. Therefore, as the inflow
pattern changes flow distribution to the individual treatment lines
also changes. However, a reasonably constant flow during the Monday
thru Thursday period of the operating week has been maintained by
pump throttling. On Fridays, flow is lower and more frequent "off"
periods are experienced in pump operations. This results in a lower
daily flow to treatment facilities under study and accounts for a
significant part of recorded variation. It should be noted that the
Equalization Basin is arranged only for waste quality equalization and
does not provide for flow equalization.
A summary of operating data for Stage 1 is shown in Table k. The data
indicates high, low, and average values. Analyses are based on 2A-hour
composite samples. Values shown under any column heading do not neces-
sarily occur on the same day.
At the close of Stage 1, the following preliminary conclusions could
be drawn about the two waste treatment methods:
1. The Bio-Disc could not treat 133,000 gpd (25 percent of the design
plant flow) and achieve 90 percent BODj. removal.
2. With adequate equalizing storage prior to treatment, the wide
variations in wastewater pH and temperature were minimized.
3. More satisfactory treatment was achieved in the Bio-Disc at lower
flow rates provided.
4. A long detention period in the Equalization Basin produced a septic
influent for subsequent treatment processes.
5. The activated sludge process generally removed 90 percent of the
BOD^ at an average flow of 92,000 gpd (1? percent of the total
plant design flow), with varied MLVSS levels.
40
-------
TABLE 4
DATA SUMMARY
STAGE 1
H igh Low Average
Raw Waste
BODr, mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, lb BOD /lb MLVSS
Loading, lb BOD^/1,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Vollume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BOD5 Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
1,470
81,900
1,040
0.183
5,384
0.339
5.78
32.0
418.
409
12,100
62
99.6
412
92
165
196
4
0.011
484
0.005
0.17
532.4
25.
56
3,090
9
77.6
6
0
589
2,336
151
0.092
2,470
0.101
1.95
63.7
210.
169
6,406
29
93.9
53
28
Bio-Disc System (Line 4)
Flow, mgd 0.175 0.005 0.057
Biological Loading, lb BOD,./
1,000 sq ft/day ' 35.0 0.5 7.9
Hydraulic Loading, gal/sq ft/day 3.89 0.11 1.27
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day 764 22 249
Effluent BOD5, mg/1 1,160 35 251
BOD Removal Efficiency, % 92.6 <0 70.1
Effluent COD, mg/1 1,319 71 385
Effluent Suspended Solids, mg/1 244 0 55
-------
6. The activated sludge process was not noticeably sensitive to
variations in influent waste characteristics such as pH and
temperature. This indicated that equalization of waste entering
this process was of questionable benefit. This was not unexpected
in view of the sizeable inherent equalization capacity of the
aeration basin.
Stage 2 (February 7 to February 20, 1972 - 2 weeks)
Originally it had been planned to operate the Bio-Disc and activated
sludge processes at flows of 133,000 gpd each during this stage. However,
Stage 1 experience indicated that a lower flow should be applied to the
Bio-Disc. The revised scheduled lower flow was 60,000 gpd.
Scheduled MLSS concentration in activated sludge process was 1,250 mg/1.
Although the stage was scheduled for three weeks of operation, the acti-
vated sludge bio-mass grew so rapidly at the average waste flow of
135,000 gpd that MLSS concentrations of 1,250 mg/1 could not be maintained
without excessive waste of sludge. BOD_ removals varied from 92.1 to
98.9 percent and averaged 96.1 percent.
The Bio-Disc, during Stage 2, received wastewater flows varying from
A3,000 to 7^,000 gpd, and averaged 63,000 gpd. BOD removals ranged from
68.5 to 78.8 percent, and averaged 75.1 percent. The contents of the
Equalization Basin continued to be septic.
A summary of operating data for Stage 2 is shown in Table 5 and conclusions
drawn from Stage 2 operations are as follows:
1. An average BOD_ removal of 96.1 percent in the activated sludge
process at a MLSS concentration of 1,250 mg/1 indicated that better
than design performance could be achieved at this relatively low
MLSS concentration.
-------
TABLE 5
DATA SUMMARY
STAGE 2
High Low Average
Raw Waste
BOD5, mg/1 1 ,080 605 775
COD, mg/1 1,861 641 1,168
Suspended Solids, mg/1 694 14 139
Activated Sludge System (Line 3)
Flow, mgd 0.162 0.072 0.135
MLVSS, mg/1 1,920 952 1,471
F/M, Ib BOD /lb MLVSS 0.613 0.177 0.350
Loading, lb BOD /I,000 cu ft/day 4.88 2.09 3-73
Aeration Detention, hrs 36.1 81.3 43.4
Clarifier Overflow, gal/sq ft/day 370. 165 309
Sludge Volume Index 134 65 91
Return Solids Concentration, mg/1 6,430 3,030 4,795
Effluent BOD mg/1 85 10 38
BOD Removal Efficiency, % 92.1 98.9 96.1
Effluent COD, mg/1 191 36 81 .
Effluent Suspended Solids, mg/1 130 12 29
Bio-Disc System (Line 4)
Flow, mgd 0.074 0.043 0.063
Biological Loading, lb BOD-/
1,000 sq ft/day 5 14.6 5-7 9.5
Hydraulic Loading, gal/sq ft/day 1.64 0.96 1.40
Equalization Time, hrs 5.5 5.2 5.4
Clarifier Overflow, gal/sq ft/day 323 188 275
Effluent BOD5, mg/1 277 170 216
BOD Removal Efficiency, % 78.8 68.5 75.1
Effluent COD, mg/1 368 77 282
Effluent Suspended Solids, mg/1 100 0 33
-------
2. The contents of the Equalization Basin continued to be septic even
with a part of the flow diverted to the activated sludge process to
reduce detention time.
3. BODj. removal averaging 75 percent at the hydraulic rate of 63,000 gpd
through the Bio-Disc was not satisfactory. This was undoubtedly due,
in part, to the septic condition of waste entering the Bio-Disc.
k. The BOD,, content of the incoming raw waste continued to vary signi-
ficantly.
Stage 3 (February 21 to February 27, 1972 - 1 week)
Results of Stage 3 operations are shown in Table 6. Flows to the activated
sludge process averaged 156,000 gpd which is higher that) the scheduled flow
of 133,000 gpd. The target MLSS level was 2,500 mg/1 . Actual MLSS levels
varied from 1,232 to 3,284 mg/1 and averaged 2,500 mg/1. BOD removals
averaged 92.8 percent.
The Bio-Disc operated at an average flow of 69,000 gpd. Based on only
one sample, BOD removed was only 40 percent. This reduced performance
compared to Stage 2 could be attributed to a flow increase of approximately
15 percent and a lower influent BODj. concentration. It was, therefore,
decided to reduce flow to the Bio-Disc and initiate Stage 3A.
Stage 3A (February 28 to March 12, 1972 - 2 weeks)
For the activated sludge process, operating conditions were at essentially
the same levels as Stage 3. Flows averaged 123,000 gpd, and MLSS levels
varied from 1,650 to 2,9^2 mg/1 and averaged 2,198 mg/1. BOD removal
averaged 97.9 percent. F/MLVSS levels for Stages 3 and 3A averaged 0.22.
For the Bio-Disc, average flows were reduced to ^5,000 gpd (8.5 percent of
plant design flow). The effluent from the Equalization Basin continued
to have septic characteristics pending installation of aeration equipment.
-------
Raw Waste
TABLE 6
DATA SUMMARY
STAGE 3
, mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD5/lb MLVSS
Loading, Ib BOD-/1 ,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
S 1 ud ge Vo 1 ume I ndex
Return Solids Concentration, mg/1
Effluent BOD_, mg/1
BOD5 Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
F 1 ow , mgd
Biological Loading, Ib BOD,./
1,000 sq ft/day 5
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD5, mg/1
BOD_ Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
*0nly one sample.
High
Low
Average
_^.^fc_
620
710
482
0.175
2,922
0.394
3.52
33.5
400
107
8,960
21
92.8
94
38
0.078
7.7
1.73
.7.1
341
270
40.0
341
62
290
370
44
0.100
1,072
0.092
1.70
58.6
229
67
3,430
20
92.8
50
24
0.050
4.2
1.11
4.3
218
174
40.0
235
16
455
540
263
0.156
2,187
0.243
2.61
37.5
357
95
5,774
21
92.8
71
31
0.069
6.0
1.53
4.9
301
222
40.0*
2,694
33.6
A.W.BERC LIBRARY U.S. EPA
-------
The Bio-Disc, although receiving a septic influent, showed a decided
improvement in BOD,, removal rates. Removal rates varied from 55.7 to
3k.3 percent, and averaged 92.4 percent for the final week of this stage.
This was accomplished while the actual influent weight of BOD,, increased
from an average of 268 pounds per day during the week of February 21, to
an average of 333 pounds per day for the week of March 6.
Operating data for Stage 3A are shown on Table 7 and conclusions drawn
from Stage 3A are as follows:
1. Activated sludge process performance of 98 percent removal was
excellent with a flow of 123,000 gpd and MLSS concentrations
ranging from 1,650 to 2,9^2 mg/1. This indicated an increased
BOD removal efficiency over that shown in Stage 2.
2. At the lower flow rates of k5,QOQ gpd, the Bio-Disc performance
increased dramatically to an average of 92.A percent in the
second week of this stage.
Stage k (March 13 to April 2, 1972 - 3 weeks)
Results of Stage 4 operations are shown in Table 8. Flow to Aeration
Basin No. 3 averaged 11^,000 gpd (21 percent of total plant design flow),
and MLSS levels averaged 3,615 mg/1. This was an increase in MLSS of
nearly 1,500 mg/1 over that in Stage 3A. Maintaining this higher level
was aimed at determining effect and performance. F/MLVSS ratios averaged
0.17, and BODj. removal rates averaged 93-7 percent. The process continued
to receive about 50,000 gpd of septic effluent from the Equalization Basin,
while the remainder of the flow consisted of raw waste. This division of
flow was made to reduce detention time in the Equalization Basin. The
system appeared to be unaffected by any sudden changes in influent pH or
temperature.
-------
TABLE 7
DATA SUMMARY
STAGE 3A
Hi gh Low Average
Raw Waste
BOD , mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, lb BOD /lb MLVSS
Loading, lb BOD /I ,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BOD,. Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
Flow, mgd
Biological Loading, lb BOD /
1 ,000 sq ft/day
Hydraulic Loading, gal/sq ft/day
Equal ization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD , mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
1 ,280
1,443
472
0.147
2,604
0.287
4.51
39.8
336.
153
12,950
24
98.9
94
70
0.061
10.1
1.36
12.1
266
285
94.3
588
32
460
708
60
0.069
1,460
0.088
1.27
84.9
158.
66
3,590
7
97.2
49
6
0.034
3.0
0.76
11.6
148
51
55.7
168
12
793
1 ,004
182
0.123
1,929
0.210
3.27
47.6
281 .
120
5,873
18
97-9
75
20
0.045
6.6
1.00
11.9
197
173
75.4
301
19
-------
TABLE 8
DATA SUMMARY
STAGE 4
High Low Average
Raw Waste
BOD,., mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, lb BOD /lb MLVSS
Loading, lb BOD^/1,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BOD5 Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
2,320
2,730
384
0.155
4,424
0.594
12.30
37.8
354
139
10,260
108
97.9
208
94
425
516
0
0.033
2,486
0.048
1.68
177.5
75
99
3,500
18
88.4
52
6
949
1,147
134
0.114
3,060
0.174
4.17
51.4
261
116
7,329
52
93.7
105
50
Bio-Disc System (Line 4)
Flow, mgd 0.065 0.025 0.049
Biological Loading, lb BOD_/
1,000 sq ft/day 5 23.2 3.8 8.8
Hydraulic Loading, gal/sq ft/day 1.44 0.56 1.09
Equalization Time, hrs 11.6 10.6 10.9
Clarifier Overflow, gal/sq ft/day 284 109 214
Effluent BGD5, mg/1 iy4 99 ]38
BOD,. Removal Efficiency, % 87.5 70.5 82.7
Effluent COD, mg/1 285 145 215
Effluent Suspended Solids, mg/1 58 8 26
-------
The Bio-Disc received an average daily flow of ^9,000 gallons. BOD
removals ranged from 70.5 to 87.5 percent and averaged 82.7 percent.
Removals were lower than obtained under similar conditions with Stage 3A.
The septicity of the influent waste flowing to the Bio-Disc was considered
to be a contributing factor to the low BOD,. removal rates. Therefore, work
was initiated on the design and installation of an aeration system for the
Equal izat ion Basin .
Conclusions drawn from Stage k operations are as follows:
1. The activated sludge process provided BOD removal of greater
than 90 percent at all flow, MLSS, and F/MLVSS levels studied to
this point. No optimum loading could yet be determined.
2. BOD removal by the Bio-Disc decreased from that experienced in
Stage 3A. This could be due to somewhat higher average
j.
concentrations and the slightly higher hydraulic loading, although
septicity of the influent was also a factor.
3. Until a method for removing the septic conditions in the equali-
zation basin could be provided, it was decided to maintain the
flow to the Bio-Disc at about ^5,000 gpd. A temporary aeration
system was implemented by installing an air hose in the inlet well
of the Bio-Disc to provide some improvement in the DO level of the
Equalization Basin effluent. This was done at the suggestion of
the manufacturer.
Stage 5 (April 3 to April 16. 1972 - 2 weeks)
Total plant flow during this stage averaged 292,000 gpd. Daily average
flow to the activated sludge process was 103,000 gallons. MLSS levels
ranged from 3,868 mg/1 to 4,616 mg/1 and averaged k ,23k mg/1 . F/MLVSS
ranged from 0.0^8 to 0.210. BODj. removals averaged 96.6 percent.
Flow to the Bio-Disc averaged 45,000 gpd. BOD removals ranged from 57.2
to 81.7 percent, and averaged 7^-8 percent.
-------
The following conclusions are drawn from the results of Stage 5 opera-
tions which are summarized In Table 9'-
1. It was initially anticipated that after Stage 5 operations were
complete, an optimum MLSS level would be selected. Since BOD_
removals had been excellent at all levels, no optimum could be
chosen. It was decided to continue to maintain an MLSS concen-
tration in the 3,500 to 4,500 mg/1 range. Such a level would
provide adequate protection for any moderate shock loading without
upset, and still provide good BOD,, removal.
2. Average BOD,, removal by the Bio-Disc declined from that achieved
in Stage 5. Average influent BOD,, was somewhat higher during this
period.
3. It was believed to be desirable to continue Bio-Disc operation
with an influent of about 45,000 gpd until the Equalization
Basin aeration system was installed and the septic conditions were
eliminated.
Stage 6 (April 17 to May 14, 1972 - 4 weeks)
The activated sludge process operated during this stage at concentrations
which varied from 2,676 to 4,756 mg/1 and averaged 3,661 mg/1. It was
planned to reduce flows to determine any effect on performance. Flows
ranged from 27,000 to 150,000 gpd and averaged 79,000 gpd. F/MLVSS values
ranged from 0.029 to 0.253, and averaged 0.083. BOD,, removals averaged
97.6 percent.
Flows to the Bio-Disc ranged from 15,000 to 72,000 gpd, and averaged
48,000 gpd. BOD removals ranged from 51.3 to 94.3 percent, and averaged
86.1 percent.
On May 11, the Equalization Basin aeration system became operable. This
aeration system consists of a 120 cfm blower plus air piping and dlffusers.
By the end of Stage 6 (May 14) septic conditions in the basin had been
substantially reduced, although no measureable DO was present in the
eff1uent.
50
-------
TABLE 9
DATA SUMMARY
STAGE 5
Raw Waste
BOD_, mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD5/lb MLVSS
Loading, Ib BOD-/1.000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD,., mg/1
BOD_ Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Blo-Dlsc System (Line 4)
Flow, mgd
Biological Loading, Ib BOD,./
1 ,000 sq ft/day '
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD5, mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
High
1,300
1,945
1,184
0.148
3,910
0.210
6.60
39.6
338
204
12,000
37
97.9
100
104
0.060
11.8
1.33
12.7
262
264
81.7
597
98
Low
558
702
32
0.035
3,144
0.048
1.56
167.3
80
90
3,350
27
93.4
12
6
0.018
3.4
0.40
11.3
79
210
57.2
267
8
Average
1,021
1,401
406
0.103
3,610
0.107
3.23
56.9
235
118
7,313
32
96.6
69
43
0.045
8.1
1.00
12.0
197
243
74.8
424
34
51
-------
As Stage 6 progressed, the MLSS in all three aeration basins began to
exhibit poor settling characteristics, as determined by the Settled Volume
Test. During the week of April 17, tests using a 1,000 ml sample and 30-min-
ute settling period, indicated sludge levels from all three basins were in
the range of 500 to 800 ml. These remained at this level through April 27.
On April 28, the 30-minute levels rose to 980 ml for samples from Aeration
Basin Nos. 1 and 2. The levels for Aeration Basin No. 3 also rose into the
800 to 950 ml range during the week of May 1. Since that time, with the
exception of occasional periods of a few days of lower readings, 30-minute
settling values for mixed liquor from all basins have been greater than
700 ml. These high 30-minute settling values explain the relatively low
suspended solids content of the waste sludge. This factor has caused
waste sludge quantities to be two to three times that originally estimated.
Addition of polymers to promote settling has been only slightly successful.
Results of Stage 6 operations are summarized in Table 10. Conclusions
drawn from this stage are as follows:
1. The activated sludge process continued to provide acceptable
treatment even though a poor settling sludge was produced.
2. BOD_ removal provided by the Bio-Disc, although improved over
previous stages, was still not consistently in the 90 percent
range.
Stage 7 (May 15 to June 18. 1972 - 5 weeks)
It was suggested by the project officer that consideration should be
given to reducing flow through aeration basin and again supplying both
the Bio-Disc and the activated sludge processes with the same quality of raw
waste. Therefore, flows to both were routed through the Equalization Basin.
The scheduled flow to each process was ^5,000 gpd. The total flow of
90,000 gpd would yield an average detention period of approximately 12 hours
in the Equalization Basin. Equipment for aeration of the Equalization Basin
was in operation.
52
-------
TABLE 10
DATA SUMMARY
STAGE 6
Raw Waste
BOD,., mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD5/lb MLVSS
Loading, Ib BOD /I ,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BODj., mg/1
BODj. Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
Flow, mgd
Biological Loading, Ib BOD /
1,000 sq ft/day b
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD5, mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
High
1,390
2,04?
900
0.150
4,072
0.253
4.75
39.0
343
300
11,300
42
98.8
95
78
0.072
15.5
1.60
17.7
314
326
94.3
529
84
Low
355
444
16
0.027
2,258
0.029
0.88
216.9
62
95
4,040
7
95.6
31
2
0.015
2.1
0.33
8.7
66
44
51.3
67
4
Average
747
1,032
344
0.079
3,105
0.083
1.99
74.1
181
198
6,346
20
97.6
62
28
0.048
6.6
1.07
11.9
210
108
86.1
196
38
53
-------
Results of Stage 7 operations are summarized in Table 11. Flows to
Aeration Basin No. 3 ranged from 33,000 to 63,000 gpd and averaged
50,000 gpd. MLSS concentrations varied from 2,392 to 5,^84 mg/1 and
averaged 3,358 mg/1. F/MLVSS ratios were low, ranging from 0.009 to
0.127 and averaging 0.062. BOD removal rates averaged 95-0 percent.
The Bio-Disc received an average of ^5,000 gpd (8.5 percent of total
plant design flow); total daily flows ranged from 10,000 to 59,000 gpd.
Average BOD,, removal rates varied from 76.0 to 96.9 percent and averaged
91.6 percent. These removals were achieved on an average daily BOD,, load
which, on a weight basis, was comaprable to the loads in previous stages.
Conclusions drawn from this stage of operation include:
1. At comparable hydraulic loadings of approximately 50,000 gpd,
and treating the same influent waste, both processes provided
average BOD removal of greater than 90 percent.
2. Based upon results of previous stages, the activated sludge process
was loaded at a rate well below demonstrated capacity.
3. The Bio-Disc appeared to be operating near its capacity to treat
this type of wastewater based on BOD,, removed.
Stage 8 (June 19 to July 16, 1972 - k weeks)
During this stage all flow to both processes continued to be routed through
the Equalization Basin.
Results of operations are summarized in Table 12. This stage ended on
July 16, when the distillery began an annual shutdown for vacations and
maintenance. During this four-week period, the activated sludge process
received an average of 78,000 gpd. MLSS concentrations varied from 2,7^6
to 5,986 mg/1 and averaged 4,208 mg/1. F/MLVSS ratios varied from 0.0^5
to 1.33 and averaged 0.223. The extremely high upper value occurred on
July 12, when a BOD,, shock load of more than 31,000 pounds entered the
-------
TABLE 11
DATA SUMMARY
STAGE 7
Raw Waste
BOD,., mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD /lb MLVSS
Loading, lb BOD /I, 000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD mg/1
BODj. Removal Efficiency, %
Effluent COD . mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
F 1 ow , mgd
Biological Loading, lb BODq/
1 ,000 sq ft/day 5
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BODj., mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
High
1 ,800
2,665
1,738
0.063
4,606
0.127
3.44
93-0
144
257
9,680
129
98.9
240
176
0.059
16.0
1.31
12.4
258
143
96.9
493
130
Low
121
258
42
0.033
1 ,048
0.009
0.22
177-5
75
36
1,910
7
82.4
26
6
0.010
0.9
0.22
10.4
44
23
76.0
45
6
Average
1,004
1,325
462
0.050
3,350
0.062
1.70
117.1
114
219
5,482
40
95.0
85
51
0.045
8.4
1.00
11.3
197
67
91.6
135
37
55
-------
TABLE 12
DATA SUMMARY
STAGE 8
Raw Waste
BOD,., mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD /lb MLVSS
Loading, lb BOD ,71 ,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BQD Removal Efficiency, %
Effluent COD , mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
F 1 ow , mgd
Biological Loading, lb BOD /
1,000 sq ft/day 5
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD5> mg/1
BOD Removal Efficiency, %
Eff 1 uent COD, mg/1
Effluent Suspended Solids, mg/1
High
9,680
9,635
2,264
0.092
5,986
1.33
28.81
63.7
210
180
10,630
39
99.0
4 Ik
178
0.086
135.0
1.91
8.3
376
840
95.6
1,092
188
Low
690
990
244
0.033
2,278
0.045
1.21
177.5
75
63
1,700
20
97.2
35
6
0.027
5.3
0.60
6.5
118
53
49.1
63
2
Average
1,992
2,723
804
0.078
3,649
0.223
5.49
75.1
178
114
6,361
27
97-9
113
43
0.071
27-3
1.58
7-2
310
269
80.8
411
68
56
-------
treatment plant. The high loading was caused by a major spill of alcohol
in the plant. The activated sludge process was able to treat the resulting
one day load of over 7,000 pounds of BOD,, with no noticeable upset to the
system.
COD loading was essentially the same as BODj.. This is not unexpected since
the added v/aste was ethanol . Data on BOD and COD removal for July 12,
the previous day, and the two following days are as follows:
BOD
Influent, Ib
Effluent, Ib
Removal, %
COD
Influent, Ib
Effluent, Ib
Removal, %
The major effect on effluent quality should be experienced in the two days
following, although some effect would be continued for an additional period.
At a flow of 78,000 gpd, the aeration basin has a detention time of slightly
over three days. Other parallel basins with shorter detention periods did
not perform equally well although sufficient test data is not available to
document this. BOD,, removal rates for this stage averaged 97-9 percent.
The Bio-Disc received an average flow of 71,000 gpd. BOD,, removal rates
varied from ^9.1 to 95.6 percent and averaged 80.8 percent. The BOD,.
removal dropped to 49.1 percent on July 13, the day following the shock
load.
uly 11
820
15
98.2
1,050
26.3
97.5
July 12
7,030
--
--
7,000
93.7
98.7
July 13
990
23.4
97-7
1,830
39.1
97.9
July 14
2,600
--
--
3,630
66.6
99.2
57
-------
During Stage 8, both treatment systems were receiving an average of more
than three times the weight of BOD_ received in Stage 7. The activated
sludge process continued to provide excellent removal. The lower removal
efficiency of the Bio-Disc indicated that a lower BOD_ or hydraulic loading,
or both, would be necessary to achieve 90 percent BOD_ removal consistently.
Based on BODC removal performance, it was concluded that the activated
5 *
sludge process should receive hydraulic loads of progressively greater
magnitude following the annual distillery shutdown period. The activated
sludge process exhibited no recognizable sensitivity to sudden changes in
influent pH and temperature. Therefore, it was decided that in subsequent
stages only the Bio-Disc influent would flow through the Equalization
Basin. Flow to the Bio-Disc process for Stage 9 would be again increased
to about 25 percent of total plant design flow (133,000 gpd). This would
determine what affect aeration of Equalization Basin would have on performance
at higher flows. Subsequent loads would be determined on the basis of the
unit's response.
Stage 9 (September 11 to October 1, 1972-3 weeks)
In late August plant production was resumed and Stage 9 of waste treatment
plant testing was resumed on September 11. During this period the activated
sludge process received an average flow of 118,000 gpd. MLSS concentrations
varied from 2,936 to 5,254 mg/1 and averaged 4,237 mg/1. F/MLVSS ratios
ranged from 0.079 to 0.257 and averaged 0.132. BODj. removals averaged 97.6 per-
cent.
The Bio-Disc received an average flow of 114,000 gpd. Aeration of the
Equalization Basin continued with this and all subsequent stages. BOD_
removals ranged from negative values (effluent concentrations higher than
influent) to 62.4 percent. Process effluent was of such poor quality that
it was all routed from Clarifier No. 4 to Sludge Well No. 2 and returned
to Aeration Basin Nos. 1 and 2 for more complete treatment.
58
-------
The program of Increasing hydraulic loads to the activated sludge process
would be continued with resulting shorter aeration times and higher
F/MLVSS ratios. MLSS concentrations would be kept at about *ป,000 mg/1 .
Flow to the Bio-Disc would be reduced to 65,000 gpd.
Stage 9 operating results are summarized in Table 13.
Stage 10 (October 2 to October 29, 1972 - ^ weeks)
Scheduled flow to the activated sludge process was 185,000 gpd. This
higher flow was planned to determine the effect of higher loading on
process performance. Actual flow ranged from 95,000 to 196,000 gpd and
averaged 170,000 gpd. MLSS varied from 3,685 to 6,935 mg/1 and averaged
A,860 mg/1. BOD,, removal varied from 9^.6 to 98.6 percent with an average
of 96.9 percent for the period.
Scheduled flow to the Bto-Dtsc was 65,000. It had been hoped that
accumulation of bio-mass, aeration of the Equalization Basin contents,
and minimizing pH and temperature peaks by adequate equalization time
would provide Improved performance at this flow. Actual flow averaged
55,000 gpd with a range of 28,000 to 132,000 gpd. Hydraulic loading
varied from 0.62 to 2.93 gpd per sq ft with an average of 1.22 gpd per sq
ft. BOD_ removal averaged 83.2 percent which Is somewhat higher than the
62.k percent averaged removal achieved at the 11*1,000 gpd flow in Stage 9.
Performance data for Stage 10 are shown on Table 1A and conclusions drawn
from Stage 10 operations are as follows:
1. BOD,, removal with the activated sludge process continued to be in
excess of 90 percent at higher flow rates.
2. Reduction In the flow to the Bto-Dtsc from 11^,000 gpd In Stage 9
to 55,000 gpd In Stage 10 did Increase removal efficiency from
62.** to 83.2 percent.
59
-------
TABLE 13
DATA SUMMARY
STAGE 9
Raw Waste
BOD,., mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD5/lb MLVSS
Loading, Ib BOD /I ,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BODj. Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
F 1 ow , mgd
Biological Loading, Ib BODj./
1,000 sq ft/day b
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD,., mg/1
BOD,. Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
High
1,640
3,031
1,438
0.161
4,328
0.257
6.48
36.4
368
20k
7,910
26
98.7
111
62
0.140
34.1
3.11
10.2
611
2,240
62.4
>1,876
934
Low
403
640
56
0.086
2,380
0.079
1 .82
68.1
197
68
3,920
1.1
96.5
18
2
0.086
9.9
1.91
8.4
376
398
<0
395
10
Average
936
1,383
594
0.118
3,488
0.132
3.75
49.6
270
150
5,772
20
97.6
56
23
0.114
19.6
2.53
9.4
498
909
925
434
60
-------
TABLE 14
DATA SUMMARY
STAGE 10
Raw Waste
BOD5, mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, lb BOD /lb MLVSS
Loading, lb BOD /I, 000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BOD,. Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
F 1 ow , mgd
Biological Loading, lb BOD,./
1 ,000 sq ft/day
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD , mg/1
BODj. Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
High
1 ,280
2,571
1,310
0.196
5,704
0.217
7.07
29.9
448
174
13,500
29
98.6
93
42
0.132
16.8
2.93
8.0
576
246
97.3
632
518
Low
248
336
30
0.095
3,094
0.038
1.48
61.6
217
62
3,590
9
94.6
16
4
0.028
2.6
0.62
37.9
122
16
40.0
16
8
Average
709
1,217
490
0.170
4,053
0.128
4.10
34.4
389
130
7,445
21
96.9
50
17
0.055
7.2
1.22
19.3
240
106
83.4
202
181
61
-------
Stage 11 (October 30 to November 26, 1972 - 4 weeks)
The flow to the activated sludge process was scheduled for an increase to
212,000 gpd. Actual flow varied from 86,000 to 222,000 gpd with an average
of 195,000 gpd. It was planned to maintain MLSS at 4,000 mg/1; actual MLSS
averaged 4,025 mg/1. F/MLVSS values varied from 0.037 to 0.361 with an
average of 0.163. With this higher flow, average BOD- removal of 96.7 per-
cent was essentially the same as the previous stage with a lower flow.
However, a combination of increased flow and a change in the settling
characteristics of the mixed liquor suspended solids resulted in the need
to reduce overflow from the clarifier by increasing the underflow. This
added underflow was directed to other treatment units.
In Stage 10, SVI ranged from 100 to 180 ml/gm. In this stage a number of
higher values up to 290 ml/gm were experienced.
It was planned to again increase flow to the Bio-Disc slightly from that
used in the previous stage. Scheduled flow was 72,000 gpd while actual
flows varied from 27,000 to 74,000 gpd with an average of 65,000 gpd.
This is equivalent to an average loading of 1.44 gpd per sq ft of Bio-Disc
surface. During the week of November 13, effluent BODj. ranged from 140 to
335 mg/1. Effluent was returned to Aeration Basin Nos. 1 and 2. The reason
for this upset was not determined. Effluent BODj. values were not used in
computing average. BOD- removal averaged 78.8 percent.
Operating data for Stage 11 are summarized in Table 15. Conclusions drawn
from Stage II operations are as follows:
1. With the higher flows to the activated sludge process, the BOD
removal of 96.7 percent was essentially the same as for the previous
stage. However, clarifier overflow rate should be limited to
400 gpd/sq ft.
2. The higher flow to the Bio-Disc resulted in a reduction in average
BOD removal from 83.4 percent in Stage 10 to 78.8 percent in
Stage 11. To achieve 90 percent removal flow must be limited to a
much lower level.
62
-------
TABLE 15
DATA SUMMARY
STAGE 11
Raw Waste
BOD , mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD /lb MLVSS
Loading, lb BOD^/1,000 cu ft/day
Aeration Detention, hrs
Clarifier Overflow, gal/sq ft/day*
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD , mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Bio-Disc System (Line 4)
Flow, mgd
Biological Loading, lb BOD,./
1,000 sq ft/day ^
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
Clarifier Overflow, gal/sq ft/day
Effluent BOD5, mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
High
1,330
2,328
1,758
0.222
4,650
0.361
9.28
26. 4
409
298
8,460
25
98.6
123
112
0.074
16.5
!.64
14.3
323
335
87.4
407
182
Low
296
383
54
0.086
2,246
0.037
0.91
68.1
89
86
4,820
12
92.7
8
6
0.027
1.5
0.60
39.3
118
78
74.3
37
6
Average
593
1,070
387
0.195
3,475
0.163
4.18
30.0
263
162
6,393
18
96.7
53
27
0.065
7.7
1.44
16.3
284
149
78.7
229
51
*Part of flow from aeration basin diverted as clarifier underflow to avoid
carryover of suspended solids.
63
-------
Stage 12 (December 4 to December 24, 1972 - 3 weeks)
During this final stage of study, the Bio-Disc and activated sludge pro-
cesses were operated in series. There was a one week delay in starting
this stage after completion of Stage 11. Flow from the Equalization
Basin was directed through the Bio-Disc and then to Aeration Basin No. 3-
Effluent from Aeration Basin No. 3 was proportioned between Clarifier
Nos. 3 and k to achieve nearly equal surface overflow rates. This arrangement
required some temporary piping changes.
Scheduled flow was 265,000 gpd; actual flow averaged 224,000 gpd. BOD
removal decreased to an average of 89-9 percent. This average removal rate,
however, was influenced greatly by one low value.
System performance for this stage is best shown by a detailed tabulation
of BODj. data. Operational data are shown in Tables 16 and 17. The
conclusion drawn from Stage 12 is that series operation offered no advan-
tage over parallel operation.
-------
TABLE 16
BOD DATA - SERIES OPERATION
Date
Dec 4
5
6
7
8
11
12
13
14
15
18
19
20
21
22
Flow
(1 ,000 gpd)
225
221
204
279
146
252
250
261
243
184
263
242
143
262
182
Inf 1 uent
BOD
(mg/1 )
1,055
4,125
920
1,485
795
1,195
1,115
705
1,035
1,410
--
545
--
675
Bio-Disc
Effluent
BOD -F
(mg/1)
--
493
--
1,385
--
270
--
663
--
--
--
--
--
--
Activated Sludge
Effluent
BOD -F
(mg/1)
--
43
--
560
--
--
31
--
17
--
--
--
--
BOD
(SgTTT
--
146
605
--
67
--
24
17
14
65
-------
TABLE 17
DATA SUMMARY
STAGE 12
Raw Waste
BOD mg/1
COD, mg/1
Suspended Solids, mg/1
Activated Sludge System (Line 3)
Flow, mgd
MLVSS, mg/1
F/M, Ib BOD5/lb MLVSS
Loading, Ib BOD^/1,000 cu ft/day
Aeration Detention, hrs
Clarlfier Overflow, gal/sq ft/day
Sludge Volume Index
Return Solids Concentration, mg/1
Effluent BOD5, mg/1
BOD_ Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Blo-DIsc System (Line 4)
Flow, mgd
Biological Loading, Ib BOD,./
1 ,000 sq ft/day b
Hydraulic Loading, gal/sq ft/day
Equalization Time, hrs
High
A, 125
6,215
2,026
0.279
4,212
NA
--
21.0
201
8,990
605
97.7
745
464
0.279
169.0
6.20
3.8
Low
545
722
86
0.143
742
NA
40.5
--
92
1,260
14
59.3
18
4
0.143
22.0
3.18
7.4
Clarifier Overflow, gal/sq ft/day
Effluent BOD5, mg/1
BOD Removal Efficiency, %
Effluent COD, mg/1
Effluent Suspended Solids, mg/1
Average
1,255
1,837
816
0.224
2,721
NA
26.2
127
5,489
146
88.9
178
101
0.224
53.0
4.98
4.9
66
-------
WASTEWATER TREATMENT SUMMARY
The results of the research operation reported in the foregoing discussion
define most aspects of the capability of the two biological processes to
treat distillery wastewater. In general, the activated sludge process
performed well under all loading conditions and can confidently be used
for this type of waste treatment. The Bio-Disc system could not provide
the desired 90 percent removal of BOD,, at the design loading rate. Design
criteria must, therefore, be adjusted based upon results obtained. A
summary of performance Is shown in Tables 18 and 19.
TABLE 18
SUMMARY OF AVERAGE BIO-DISC PERFORMANCE DATA
Dally Loading
itage
2
3
3A
4
5
6
7
8
9
10
11
Influent BOD5
Ong/1)
775
455
793
949
1,021
47^
1,004
1,992
936
704
593
Flow
(1 ,000 gpd)
63
69
45
49
45
48
45
71
114
55
65
BODr
5
(lb/1 ,000 sq ft)
9.5
6.0
6.6
8.8
8.1
4.2
8.4
27.3
19.8
7.2
7.7
Hydraul ic
(gal/sq ft)
1.40
1.53
1.00
1 .09
1 .00
1.07
1.00
1.58
2.53
1 .22
1.44
BOD^ Removal
U)
75.1
40.0
75.4
82.7
74.8
86.1
91.6
80.8
83.4
78.7
Note: Aeration of Equalization Basin was initiated with Stage 7.
67
-------
TABLE 19
SUMMARY OF AVERAGE ACTIVATED SLUDGE PERFORMANCE DATA
Stage Influent BOD Flow MLVSS F/M BOD5 Removal
2
3
3A
4
5
6
7
8
9
10
11
(mg/1 )
775
455
793
949
1 ,021
747
1 ,004
1,992
936
709
593
(1 ,000 gpd)
135
156
123
114
103
79
50
78
118
170
195
(mg/1)
1,471
2,187
1,929
3,060
3,610
3,105
3,350
3,649
3,488
4,053
3,475
(Ib/lb)
0.350
0.243
0.210
0.174
0.107
0.083
0.062
0.223
0.132
0.128
0.163
(*)
96.1
92.8
97.9
93.7
96.6
97.6
95.0
97.9
97.6
96.9
96.7
68
-------
SECTION VII - ADJUSTED DESIGN CRITERIA
BASIC CRITERIA
To establish design criteria for distilling industry waste treatment, a
number of basic factors must be considered:
1. Equalization to minimize the effect of the variations in pH,
temperature, BOD,, concentration, and flow.
2. Kinetics of BOD removal.
3. Oxygen requirements.
k. Settling characteristics of suspended solids in the waste leaving
the biological step of the process.
The overall mechanisms involved in BOD removal are similar for both the
activated sludge and Bio-Disc processes. Incoming organic materials
measured in terms of BOD_ are used by viable organisms in the biological
reaction as food for normal metabolic needs and for propagation. To
ensure an efficient biological growth, the substrate must have an adequate
microorganism population, sufficient dissolved oxygen for respiration
needs, and necessary nutrients such as nitrogen and phosphorus. Temperature
and pH must be within a limited range.
The purpose of the biological reactor in the BOD reduction process is to
convert the substrate material into suspended cell mass. Suspended cell
mass is removed in a subsequent step by settling.
EQUALIZATION
Equalization for both the activated sludge and Bio-Disc processes is
required to minimize wide variations in pH and temperature characteristic
of distillery waste. At this installation some steps have been taken up-
stream from the waste treatment facilities to ensure that waste character-
istics are such as to not exceed the capability of equalization facilities.
Such steps jnclude reduction in the use of highly alkaline cleaners, partial
neutralization of demineralizer regenerants, and cooling of condensate from
feed recovery operations.
69
-------
Equalization can be provided for both processes upstream from the
biological reactor. In the case of the activated sludge process, however,
adequate equalization capacity has been shown to be inherent in the aera-
tion basin which serves as the biological reactor for that process. The
aeration basin in that process must also provide equalization capacity
to meet two other conditions:
1. Hold a sufficient inventory of active cell mass to absorb the
effect of short-term shock loads of BOD.
2. Contain sufficient substrate to maintain viable organisms during
low flow or plant shutdown periods.
Based on periods of continuous temperature monitoring and frequent pH
testing of the Bio-Disc influent data, it appears that an Equalization
Basin with a detention period of about 12 hours is necessary to meet
reported influent quality requirements of the Bio-Disc. These influent
requirements are a maximum temperature of 90 F and a pH range of 6.0 to
9.5. It was not established during the test period that operation outside
these limits was a major contributing cause of poor performance. Since
organism metabolic processes continue during equalization storage, it has
been found necessary to provide for aeration equipment to prevent an
anaerobic environment. When such aeration was initiated with Stage 7> BOD
removal appeared to increase. During the detention period some cell growth
takes place reducing the filterable BOD. It has not been possible to verify
this quantitatively.
The aeration basin of the activated sludge process has a detention time of
33 hours at design flow. Providing additional detention time in the
Equalization Basin did not improve BOD removal. A shorter detention time
than the design basis could be used under essentially all conditions. How-
ever, it is probable that BOD removal performance would decrease below
90 percent with some extreme shock loads. This is based on experience gained
with the shock load which occurred on July 12, 1972, when plant BODj. load for
that day was about 10 times the total plant design value of 3,200 pounds.
70
-------
KINETICS OF BOD REMOVAL
The process of BOD removal from a waste by the activated sludge process
is influenced by many rate mechanisms and substrate characteristics. Two
models are used frequently for characterizing performance of the biological
portion of the total process, as follows:
Model 1 : p
F = ' (McKinney Model)
o is. t * i
m
Model 2: F
L. i (Eckenfelder Model)
where: F = Effluent BOD (filtered), mg/1
F. = Influent BOD (total), mg/1
K = Constant
m
K = Constant
X = Mixed liquor volatile suspended solids, mg/1.
t = Detention time, hrs (or days).
Use of BOD rather than total first stage BOD (BOD ) is based on the
premise that the ratio BOD^/BOD. is same for influent and effluent.
The difference between the two models is that Model 1 does not directly
consider the effect of MLVSS (assumed to be proportional to active cell
mass) while Model 2 does. If the process were such that microorganisms are
in the declining growth phase (F/M ratio is low), the use of Model 1 appears
logical. However, Model 2 has been used to describe the process for many
industrial applications.
For activated sludge process these models have normally been applied to
aeration periods of k to 12 hours. However, they have also been applied
to aerated lagoons where detention times are much longer and the MLVSS
levels are much lower.
71
-------
Computation of K and K values indicated a wide variation.
m
computation of K is shown below:
Data for
Stage
2
3A
4
5
6
7
8
9
10
11
Fi
(mg/1)
775
793
949
1 ,021
1,032
1 ,004
1,992
936
709
593
F
o
(mg/1)*
27
12
23
10
13
16
17
17
13
9
t
(days)
1.81
1.98
2.14
2.37
3.09
4.88
3.13
2.07
1.44
1.25
K
m
15.3
32.8
18.8
42.7
25.4
12.7
37.2
26.2
37.3
51-7
Mixed
Liquor
Temp
(C)
9.5
10.1
11.7
12.5
14.6
13-3
21.3
22.4
15.9
13.9
K
m
@ 20 C
31.9
65.5
32.4
71.3
36.8
13.4
33.8
22.2
49.0
78.3
BOD
Removal
(*)*
96.5
98.9
97.6
99.0
98.9
98.4
99.1
98.2
98.2
98.5
-Based on BODr (filtered) in effluent.
Temperature compensation of K to 20 C does not reduce variances. The
m T-20
correction factor used was 1.071
The exact cause for variance cannot be defined. However, the following
are believed to be some of the potential contributing factors:
1. The data used are arithmetic average values. Such use is not a
truly accurate approach with the flow variations encountered.
2. The precision and accuracy of,BOD,, analysis permits a variance
in results particularly at low effluent BOD_ values. With low
effluent values an error of only a few mg/1 can change the value
of K substantially.
m '
3. Variation in the type of oxygen demanding constituents may affect
organism metabolic rates.
4. With the relatively long detention periods and low F/M ratio,
the process is beyond the normal declining growth phase and into
auto-oxidation. The kinetic formula may not be as applicable under
such condi tions.
72
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^ removal shown in data on kinetics is based on a filtered effluent
sample. BODj. associated with all cell mass or organic material removed
by filtering is not included. Therefore, to achieve 90 percent removal
of total BOD in the plant effluent would require a slightly higher BOD
removal of 92 to 93 percent based on kinetic data. Eliminating the low
value of K obtained in Stage 7 on the basis of long detention time, the
lowest value of K is 15-3 per day. Required detention time can be deter-
mined as follows:
F
_o_ _ 1
F. K t + 1
i m
with 32% Removal , _o_ _
i
Km = 15.3 (@ 9-5 C)
0.08 = 1
05.37(0 + 1
t = 0.75 days
Therefore on a conservative basis, when hydraulic detention time is in excess
of 0.75 days, kinetics will not be a limiting factor. Laboratory data and
data from other stages would indicate a shorter detention time would be
adequate to meet kinetic requirements.
For domestic waste, anticipated Bio-Disc performance can be determined on
the basis of hydraulic loading. Percent BOD removal decreases linearly
with increasing flow per unit area of active biological surface. Some
increase in percent removal takes place as influent BOD concentration
increases. This was not the case with distillery waste.
73
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There have been some very recent indications from the equipment manufacturer
that at higher influent concentrations of BODj., organic loading may be signi-
ficant, particularly when expressed in terms of weight of BOD,, per square
foot of the first stage contactor. This is possibly due to limiting mass
transfer of oxygen to the biological mass. Test data which had been
previously collected were not detailed enough to determine this effect.
The Bio-Disc used in these studies contains six stages. Based on BOD
removal progression as a first order reaction, removal kinetics should
be similar to that for a multi-stage completely mixed activated sludge
system. Attempts to reduce actual performance data to a mathematical
model were not successful.
OXYGEN REQUIREMENTS
Transfer of oxygen from the air to the waste under treatment must be
adequate to supply respiration needs of the microorganisms and maintain
an aerobic environment.
Oxygen uptake can be related to the rate of BOD_ removal, MLVSS concentra-
tion, and the conversion of the reduced forms of nitrogen such as ammonia
and protein to higher oxidized forms such as elemental nitrogen, nitrate,
and nitrite.
In the case of the activated sludge process, the rate of absorbtion of
oxygen by the mixed liquor can be determined by considering temperature,
oxygen deficit, and transfer coefficients. However, under varying condi-
tions of flow, waste strength, MLVSS, and temperature; the accuracy of
averages is subject to some question. A similar mathematical approach is
not available for the Bio-Disc.
-------
A simpler approach Is to examine the dissolved oxygen concentration of
waste leaving the biological reactor. If a concentration of 1 to 2 mg is
present, the oxygen supply Is adequate. Lower residuals indicate a
deficiency and higher levels indicate an excess.
For the activated sludge process, aeration equipment provided was generally
adequate with deficiencies occurring during certain shock load conditions.
A re-examination of design criteria Indicates that by judgment aeration
capacity should be increased about 30 percent to minimize the frequency of
low residuals.
Oxygen supply for the Bio-Disc is governed by inherent characteristics of
the equipment and is, therefore, not an Independent variable as with the
activated sludge process.
SETTLING CHARACTERISTICS OF WASTE
Even though the biological reactor Is satisfactorily converting BOD of the
waste to cell mass, overall treatment and effluent BODj. levels cannot be
satisfactorily maintained without effective final settling.
The original design provided a nominal clarifier overflow rate of ^00 gpd
per sq ft for the activated sludge process and 580 gpd per sq ft for the
Bio-Disc. These are conservatively based on Ten State Standards of 600 gpd
per sq ft for activated sludge and 800 gpd per sq ft for trickling filters.
The adjusted design criteria set the overflow rate for both the activated
sludge and the Bio-Disc processes at AOO gpd per sq ft. This limit is set
for the activated sludge process based on experience with Stage 10, where
suspended solids in the effluent averaged 17 mg/1 with a maximum of k2 mg/1.
In other stages with lower overflow rates, suspended solids concentrations
have on some days been higher than those in Stage 10. However, this is
attributed to transient loads or poor samples.
75
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The nominal overflow rate for settling of the Bio-Disc effluent, as reported
by the manufacturer, is 800 gpd per sq ft. For The American Distilling
Company wastes, satisfactory suspended solids removal has been demonstrated
at over 350 gpd per sq ft. In other instances, lower overflow rates have
yielded effluent suspended solids in excess of 100 mg/1.
It has been assumed that individual Instances of high effluent suspended
solids concentration has been due to transient conditions or poor sampling.
The adjusted design rate of *ป00 gpd per sq ft has been established by judg-
ment.
ACTIVATED SLUDGE DESIGN CRITERIA
The following conclusions can be reached from the analyses previously
presented:
1. Kinetics are not a controlling factor if detention time is
greater than 0.75 days (18 hours).
2. Aeration capacity has been deficient at times based on the
absence of dissolved oxygen in the mixed liquor. By judgment
aeration capacity should be increased about 30 percent.
3. Overflow rate for the final clarifier should be limited to
*tOO gpd per sq ft.
The fourth criteria to be considered is system equalization requirements.
This criteria can be evaluated only on the basis of experience. No
rigorous model can be defined to recognize time related variations in
waste characteristics.
Temperature of the mixed liquor during the test period was generally
maintained between 50 F and 80 F. Only infrequent instances were experienced
where temperature dropped below 50 F. These occurrences were normally
during or after a weekend or holiday period in cold weather. The mixed
liquor pH was always maintained in the range of 7.0 to 8.2. Therefore,
the original design detention period has been adequate and could be reduced
25 to 30 percent without any harmful effect on temperature and pH of the
mixed 1i quor.
76
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On the other hand equalization capacity is also required to maintain an
adequate inventory of MLVSS to handle low load periods and shock loads.
An analysis of performance as a function of F/M ratio will provide a
design basis recognizing both kinetics and equalization requirements.
Table 20 is an accumulation of all data collected on 24-hour composite
samples illustrating the relationship between the F/MLVSS ratio and the
resulting BOD,, removal. This summary illustrates good BODj. removal
rates at all F/M ratios up to 0.65. There is a good representation of
data up to F/M of 0.30 and limited information above this level. It
appears reasonable that a system can be conservatively designed for an
F/M of 0.30.
BOD /MLVSS
Range
.01 -
.051 -
.101 -
.151 -
.201 -
.251 -
.301 -
.351 -
.Ml -
.451 -
.501 -
.551 -
.601 -
.05
.10
.15
.20
.25
.30
.35
.40
.45
.50
.55
.60
.65
TABLE 20
ACTIVATED SLUDGE PROCESS
F/MLVSS AND RESULTING BOD^ REMOVAL RATES
Number
of Values
7
17
9
10
9
5
1
2
0
1
0
0
1
BOD,. Removal
Low
7*7
94.3
82.it
92.0
88. i>
94.3
97.5
99.0
92.1
High
W
98.6
98.8
98.6
98.6
98.9
98.7
99.0
95.9
Average
(%)
96.8
95.1
97.2
96.5
97.3
98.2
99.0
94.0
97.4
98.9
97-4
98.9
97-4
98
77
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The activated sludge process has demonstrated performance in excess of
the 90 percent BOD- removal used as a design basis. Therefore, original
criteria can be adjusted upward. The original and adjusted design basis
for the plant are as follows:
Or iginal Adjusted
MLVSS, mg/1 3,000
F/M, Ib BOD /day/1b MLVSS -- 0.30
Aeration Basins
Number 3 2
Volume (each), gal 244,000 252,000
Volume (total), gal 732,000 504,000
Influent BOD , Ib/day 3,200 3,800
Influent BOD , mg/1 725 860
Flow, mgd 530,000 530,000
Aeration Basin Detention, hrs 33 23
Aerators, hp 120 160
Clarifier Overflow Rate,
gpd/sq ft 400 400
Limited operating data would indicate that BOD,, removal of at least 90 per-
cent can be maintained
increasing above 0.30.
cent can be maintained at higher BOD,, influent levels with F/M ratios
BIO-DISC DESIGN CRITERIA
The Bio-Disc biological system installed at The American Distilling Company
plant cannot adequately treat the wastewater loading of 120,000 gpd origi-
nally specified; design criteria must, therefore, be re-evaluated to provide
a basis for applying the process to other installations and for arriving at
the actual capacity of the existing installation.
78
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There is a wider scattering of results obtained from the Bio-Disc unit
than from the activated sludge process. Therefore, determination of
reliable design criteria is somewhat more difficult. Shown below are the
original and adjusted design ratings. The adjusted rating appears reason-
able for the installation on the basis of actual operating results parti-
cularly those shown for Stage 7.
Orig inal Adjusted
Flow, mgd 0.120 0.0^5
Average Influent BOD , mg/1 725 860
Influent BOD , 1b/day 800 322
Organic Loading, Ib BOD /
1,000 sq ft/day ^ 17-8 7.2
Equalization Basin Detention,
hrs 8.8 12
Clarifier Overflow Rate, gpd/
sq ft 580 400
The adjusted overflow rate is determined by judgment. These values
represent the best estimate based upon available data. It would appear,
however, that the activated sludge design criteria presented are some-
what more conservative than for the Bio-Disc system. The activated sludge
process consistently achieved greater than 90 percent BOD removal, even
at loading rates considerably in excess of the revised design values
specified. The Bio-Disc, however, did not consistently maintain BOD^
removals in excess of 90 percent at the levels indicated in the revised
design criteria.
RESPONSE TO SHOCK LOADINGS
The American Distilling Company operation is typical of many industries;
wastewater loads exhibit frequent wide flucturations. A biological waste-
water treatment system must be able to accept these load variations and
consistently provide an effluent which satisfies applicable discharge
criteria. Two shock loads taken through the treatment facilities illustrate
the response of the two systems being evaluated to extreme loading conditions
79
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On Monday, March 13, 1972, which was the first day of Stage *4, 3,000 pounds
of BOD entered the activated sludge process. This resulted in an F/MLVSS
ratio of 0.6. Flow on this day was 155,000 gallons. No BOD determination
was made on the Monday effluent sample; however, COD removal was 9^.5 per-
cent. The Tuesday effluent sample, undoubtedly affected by the high load
of the previous day, yielded a total effluent BOD of 180 mg/1 or 88.k per-
cent removal. On the same day, the load to the Bio-Disc was 1,050 pounds
of BOD representing a loading rate of 0.023 pounds per day per square foot.
Flow for the day was 5^,000 yielding a hydraulic loading of 1.2 gal/sq ft/
day. However, part of the flow through the Equalization Basin was being
diverted to the activated sludge process. Detention time was estimated to
be about 10 hours. COD removal on March 13 was 90 percent of BODj. ; on
March ]k was 83.5 percent with an effluent BOD- concentration of 1 5^ mg/1.
The second major shock load occurred on Wednesday, July 12, 1972, during
Stage 8 just prior to the plant shutdown period when a total of 31,100 pounds
of BOD was received at the treatment plant. Aeration Basin No. 3 was
subjected to a loading of 7,030 pounds. This represented a F/MLVSS ratio
of 1.33- Flow for the day was 87,000 gallons. COD removal for the day was
98.7 percent. Again, no BODj. determination was available for the actual
day of the shock loading; however, on July 13 the effluent BODj. concentra-
tion was 39 mg/1 representing a removal efficiency of 97-6 percent. The
BOD,, load of 7,030 pounds was approximately seven times the nominal design
value of 1,070 pounds. Flow of 87,000 gallons per day, however, is slightly
less than one-half of the nominal design value of 177,000 gallons per day.
On July 12, the Bio-Disc received a BOD,, load of 6,1^0 pounds or a rate of
136 pounds per day per 1,000 square feet. Flow on this day was 76,000 gal-
lons resulting in a hydraulic loading of 1.69 gal/sq ft/day. The effluent
BOD on July 13 was 8^0 mg/1 and the corresponding BOD_ removal was ^9.1 per-
cent.
80
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From these data, it is apparent that the activated sludge system is capable
pf accepting shock organic loads and providing a reasonable degree of
treatment. The Bio-Disc system is much more susceptible to performance
loss as a result of the shock loads. Other examples of this are apparent
from a review of the operational stage results. The activated sludge
system performed well regardless of the equalization storage provided
prior to treatment. The Bio-Disc unit could not provide a satisfactory
effluent without equalization storage and without the addition of aeration
to the equalization storage to eliminate septic wastewater conditions.
81
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SECTION VIII - ECONOMIC COMPARISON
ORIGINAL COST OF FACILITIES
The wastewater treatment facilities for The American Distilling Company
research project were constructed under general contract awarded by
competitive bid. Two bids were received for the general construction
portion of the contract. The rotating biological contactor was bid
separately and two bids were also received for this unit.
General Construction Contract
Mobilization and General Expense $ 33,000
Chlorination and Control Building 153,22?
Grit Chamber 25,300
Sludge Bids 13,450
Concrete Headwall and Outfall 21,465
Pumps and Plumbing 23,000
Water Main 23,259
Gas Piping 2,000
Fence 3,030
Road 2,500
Electrical Work 63,208
Final Clarifiers (activated sludge) 139,271
Final Clarifier (Bio-Disc) 41,805
Equalization Basin (including aeration) 44,845
Aeration Basins 268,270
Bio-Disc Support (piling, substructure) 37,222
Subtotal $894,852
Bio-Disc
Bio-Disc including installation, auxiliaries
housing superstructure, an aeration equipment
for Equalization Basin $ 94,950
82
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Cool ing Tower
Cooling tower Including auxiliaries and
Installation $ 11,311*
Engineering
Design of facilities and resident supervision $ 106,267
Total Construction Cost $1,107,383
The above does not Include general overhead expense and special process
consultation expense.
ADJUSTED COST OF FACILITIES
In order to make a meaningful cost comparison between the activated sludge
and Blo-Dlsc processes, facilities of equal capacity must be used. There-
fore, based on the performance obtained, the size of component unit opera-
tions, and unit processes have been adjusted. An activated sludge and a
Blo-Dlsc treatment plant each with a nominal design capacity of 530,000 gal'
Ions with 90 percent BOD_ removal are compared.
For the activated sludge process, the capital cost has been determined by
removing from the original plant cost all components associated with the
Bio-Disc such as:
Cool ing Tower
Final Clarifler No. A (Bio-Disc)
Equalization Basin
Bio-Disc Support
Bio-Disc and Auxiliaries
Also, one aeration basin has been deleted and aerator capacity has been
Increased from 120 to 160 horsepower. The number of final clarifiers has
been reduced from three to two, but overflow rate has been maintained at
^00 gpd per sq ft by increasing individual clarifier size. These changes
are based on adjustments dictated by actual performance attained.
83
-------
Costs are at the levels in effect at the time of bidding in October, 1970.
The facility costs are as follows:
Mobilization and General Expense $ 33,000
Chlorination and Control Building 150,000
Grit Chamber 25,300
Aeration Basins 208,000
Final Clarifiers 115,000
Sludge Beds 13,500
Headwall and Outfall 21,500
Pumps and Plumbing 23,000
Water Main 23,300
Gas Piping 2,000
Fence 2,900
Road 2,500
Electrical Work 60,000
Total $680,000
For the Bio-Disc process, the adjusted plant size is much larger than test
facilities. Therefore, a different configuration is indicated. First,
the flat discs of the Bio-Disc used in the test facility installation are
replaced in current equipment design by an improved design with an extended
surface configuration permitting more active biological surface per unit of
floor area. Therefore, the generic term rotating biological contactor (RBC)
Is used hereinafter to describe this type of equipment. Second, the larger
installation size dictates use of an assembly of individual shafts as opposed
to the completely integrated unit used in the test facility.
The arrangement selected includes one Equalization Basin sized for a 12-hour
detention period and equipped with two 10 horsepower mechanical aerators.
The remainder of the treatment process is divided into two equal size trains.
Each train consists of the following:
Contactor (single stage - 100,000 sq ft)
Intermediate Clarifier (1,200 gpd per sq ft overflow rate)
Contactor (single stage - 80,000 sq ft)
84
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Contactor (two stage - 96,000 sq ft)
Final Clarifier (**00 gpd per sq ft overflow rate)
Cost of those components determined from current price information has
been factored to late 1970 levels. The cost of other components has been
based on actual original plant costs or adjusted based on size changes
from original plant costs.
Estimated facility costs are as follows:
Mobilization and General Expense $ 33,000
Chlorination and Control Building 1^5,000
Grit Chamber 25,300
Cool ing Tower 11,300
Equalization Basin Including Aeration 93,000
Bio-Surf Building 126,500
Bio-Surf Equipment and Auxiliaries 1^3,000
Final Clarifiers 115,000
Sludge Beds 13,500
Headwall and Outfall 21,500
Pumps and Plumbing 20,000
Water Main 23,300
Gas Piping 2,000
Fence 3,000
Road 2,500
Electrical Work 55.000
Total $832,900
To determine total investment requirements, engineering and overhead costs
must be added to the above contract costs. Engineering includes that for
both design and resident supervision. Overhead costs are estimated at
5 percent of other costs.
85
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Rotating
Activated Biological
Sludge Contactor
Construction Contract Cost $680,000 $832,900
Design Engineering 55,700 65,700
Resident Engineering 35,000 35,000
Subtotal $770,700 $933,600
Overhead 38,300 *t
Total Construction Cost $809,000 $980,000
Annual Costs
The annual costs for operating waste treatment facilities include the
fol lowi ng :
Fixed Charges
Operating Labor and Testing
Administrative Costs
Ma intenance
Chemicals and Supplies
Water
Electrical Energy
Fixed charges include depreciation, cost of money, taxes and insurance.
Depreciation is computed on a straight line basis of 5 percent using an
estimated facility life of 20 years.
The cost of money is determined on the basis that 40 percent of the invest-
ment will be equity capital and 60 percent debt capital. The required
gross return on equity is assumed to be 22 percent with half of this attri-
buted to taxes, yielding a net return of 11 percent. Debt capital interest
rate is computed at 8 percent. The cost of money based on a combination of
equity and debt capital cost is 13.6 percent. If the amortization period
were assumed equal to the estimated useful life, the capital recovery factor
is equal to the sum of depreciation plus average cost of money. This is
14.3 percent of the investment.
86
-------
Taxes and insurance are computed at 1.5 percent of investment,
A summary of fixed charges is as follows:
Depreciation
Average Cost of Money
Taxes and Insurance
Total
Activated Sludge Process
$809,000 @ 15.8% = $127,800 per year
Rotating Biological Contactor
$980,000 @ 15.8* = $15^,800 per year
During the testing period two men performed all plant operating and sample
testing duties. Cost including 20 percent fringe benefits was equal to
$26,^00 annually. It is estimated that with normal testing and operating
practices this can be reduced about 25 percent to $20,000 annually for
either process.
General administrative costs are those associated with time spent by
policy making personnel of the distillery in connection with waste treat-
ment plant personnel and technical operation. Although there is no
rigorous basis to determine this effort, it is a real factor and is esti-
mated at 10 percent of operating labor or $2,000 annually.
Maintenance was performed by regular distillery staff and averaged $1
per month or $17,300 annually. This is slightly less than 2 percent of
facility investment. For projecting costs of activated sludge and ro-
tating biological contactor facilities, maintenance is computed at 2 per
cent of investment.
87
-------
Activated Sludge
$809,000 @ 2% = $16,200 per year
Rotating Biological Contactor
$980,000 ง 2% = $19,600 per year
The cost of chemicals and supplies averaged $300 per month during the test
period. Most of these costs are associated with chemical requirements
including anhydrous ammonia, triple superphosphate and chlorine. It is
estimated that such costs with either the activated sludge or rotating
biological contactor processes would be essentially the same. Therefore,
an annual cost of $3,600 is used.
Water costs for waste treatment facility have averaged about $33 per month
during the test period. Therefore, an annual cost of $400 is used for
either type of facility.
Electrical requirements have been computed as follows using a unit cost
of $0.01785 per kilowatt hour:
Average Running
Horsepower Cost
Activated Sludge
Aerators 120 $16,000
Sludge Pumps 3 ^00
Other -- 2,500
$18,900
Rotating Biological Contactor
Equalization Basin 20 2,670
Rotating Biological Contactor Drives 28 3,730
Other ~" 2,500
$ 8,900
88
-------
A summary of annual costs are as follows:
Activated Rotating Biological
Sludge Contactor
Fixed Charges $127,800 $15^,800
Operating, Labor, and Testing 20,000 20,000
Administrative Costs 2,000 2,000
Maintenance 16,200 19,600
Chemicals and Supplies 3,600 3,600
Water 1*00 ^00
Electrical Energy 18,900 8,900
$188,900 $209,300
Both investment and annual costs are lower with the activated sludge process.
If integral plastic covers were provided for the rotating biological con-
tactors as a means of housing rather than a building, the investment cost
could be reduced $^0,000 to $^5,000. Annual costs would be reduced $7,000
to $8,000. The decision to take advantage of such savings would be contin-
gent upon individual circumstances.
89
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APPENDIX A
GLOSSARY
ACTIVATED SLUDGE PROCESS - An aerobic stabilization process for biodegrad-
able wastes accomplished by aerating a mixture of raw waste and activated
sludge to convert waste constituents to cell mass with subsequent removal
of suspended matter by settling. Activated sludge consists of agglomerated
biological mass containing microorganisms which utilize the waste constituents
as food for growth and propagation. A part of the activated sludge in the
clarifier is recirculated to the aeration basin to maintain the required
organism population. Excess sludge is wasted.
BIO-DISC - A name for a rotating biological contactor consisting of a
series of discs continuously rotating partially submerged in the waste
stream. A biological mass forms on the discs. Disc rotation alternately
exposes this mass to waste and to the air thereby providing for an aerobic
stabilization of waste constituents. Suspended biological mass transferred
to the waste stream is removed by settling.
BIOCHEMICAL OXYGEN DEMAND (BOD) - A measure of the oxygen necessary to
satisfy needs of aerobic decomposition of degradable waste constituents.
This parameter is determined by measuring oxygen depletion of sample mixed
with aerated water after an incubation period at 20 C. Standard Incu-
bation period is five days and the value so determined is designated as
BOD .
BIOCHEMICAL OXYGEN DEMAND - Filtered (BOD-F) - A BOD test performed on a
filtered sample. This approximates the biochemical oxygen demand of solu-
ble and colloidal constituents present.
90
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CHEMICAL OXYGEN DEMAND (COD) - A measure of oxygen required to approach
complete oxidation of waste constituents which are degradable by oxidation.
This test is performed by measuring remaining oxidation capacity of an
inorganic oxidizing solution continuously contacted with the sample for a
defined period and at a defined temperature.
ENDOGENOUS RESPIRATION - The decomposition of dead cell mass by living
microorganisms.
f
FOOD TO MICROORGANISM RATIO (F/M) - The ratio of the weight of BOD
entering a biological aeration system per day to the weight of mixed
liquor volatile suspended solids (MLVSS) in the aeration system.
LOADING - Various criteria used to denote unit load on treatment unit
operations or processes. Typical loading parameters are as follows:
Clariflers: Detention time, hrs ,
Overflow rate, gpd/sq ft
Sol ids load, Ib/day/sq ft
Bio-Disc: Hydraulic, gpd/sq ft
BOD, Ib/day/sq ft
Aeration Basin: BOD, lb/1,000 cu ft
Detention time, hrs
F/M, Ib BOD /day/1b MLVSS
MIXED LIQUOR SUSPENDED SOLIDS (MLSS) - The suspended solids content of mixed
liquor in an activated sludge aeration basin. Testing is performed by
filtering a sample followed by drying of residue at 103 C. Dried weight of
residue is related to volume of sample with concentration expressed as mg/1.
MIXED LIQUOR VOLATILE SUSPENDED SOLIDS (MLVSS) - The volatile portion of
the MLSS. Test is performed by measuring loss In weight of MLSS sample
residue after tgnjijlpn at 550 C. Weight after Ignition Is related to sample
s'** ฃna concentration is expressed as mg/1.
91
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NUTRIENTS - Various elements such as nitrogen phosphorus, and potassium
needed for microorganism metabolism. Deficiencies of nutrients in waste
are met by addition of ammonia - NH_ for nitrogen and triple superphosphate
Ca (rLPO,)? for phosphorus.
pH - A measure of the intensity of acid or alkaline condition of the solu-
tion. The logarithm of the reciprocal of the hydrogen ion concentration.
RAW WASTE - Waste entering the treatment facility.
RETURNED SLUDGE - Sludge removed from the clarifier and returned to the
aeration basin to maintain the desired F/M ratio of the mixed liquor.
SLUDGE VOLUME INDEX - A measure of sludge settleabi1 ity. The volume
occupied by one gram of sludge after a 30 minute settling period.
SUSPENDED SOLIDS - Solids retained by filtering a sample of waste stream.
Retained material dried at 103 C prior to weighing.
VOLATILE SUSPENDED SOLIDS - Volatile portion of suspended solids. Test
performed by measuring loss of weight of suspended solids after ignition
at 550 C.
WASTE SLUDGE - Sludge removed from clarifier and pumped to sludge lagoons.
The quantity is equal to sludge produced less that necessary for return to
aeration basin to maintain required MLSS level.
ซU.S. GOVERNMENT PRINTING OFFICE:1974 546-318/374 1-3
-------
-'J..('
WATER i. Report No.
KSOURCES ABSTRACTS
INPUT TRANSACTION FORM
2. ,?. Accession No.
< Title 5. Report Date
Activated Sludge - Bio-Disc Treatment of Distillery f-
WaStSWater _ * Performing Organization
,7. Authors) Re,,ortNo.
John L. Thomas and Lawrence G. .Koehrsen
9. Organization
11. Contract/Grant No.
The American Distilling Company
Pekin, Illinois
10. Project No.
12060 FLL
13. Type of Report and
Period Covered
12. Sponsoring Organization Environmental Protection Agency , 1070 to
IS Supplementary Notes April 1972
Environmental Protection Agency report number,
EPA-660/2-74-014, April 1974.
16. Abstract
Plant scale evaluation of activated sludge and Bio-Disc treatment of distillery
wastewater has been conducted over a period of more than one year at Pekin,
Illinois. The activated sludge process consistently provided in excess of
90 percent removal of BOD?, even at loadings greater than the treatment plant
design levels. The Bio-Disc process had to be down-rated from the original
design basis in order to approach a comparable removal efficiency. Of the
two systems evaluated, the activated sludge process was the more desirable from
standpoints of economics, treatment performance, and.ability to handle shock
loads.
This report was submitted in fulfillment of Project No. 12060 FLL by The
American Distilling Company under the partial sponsorship of the Environmental
Protection Agency. Work was completed as of May 25, 1973*
17a. Descriptors
'^Activated Sludge, ^Industrial Wastes, *Waste Identification, *Design.Criteria
Biological Treatment, Evaluation.
17b. Identifiers
*dlstillery wastes, ^rotating biological contactor, economic comparison, aeration
clarification
t7c. COWRR Field & Group
18. Availability 19. Security Class.
(Report)
20. Security Class.
(P'ge)
21. No. of Send To:
Pages
22. Price WATER RESOURCES SCII-NI ino INI ORM ATI
U.S. DEPARTMENT OF TNI. IN'l FHIOH
WASHINGTON. D. C 20240
_____ _
Abstractor J. L. Thomas \Institution
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