WATER POLLUTION CONTROL RESEARCH SERIES 12020 DIS 01/72
ANAEROBIC TREATMENT
OF
SYNTHETIC ORGANIC WASTES
U.S. ENVIRONMENTAL PROTECTION AGENCY
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WATER POLLUTION CONTROL RESEARCH SERIES
The Water Pollution Control Research Series describes the
results and progress in the control and abatement of pollution
in our Nation's waters. They provide a central source of
information on the research, development, and demonstration
activities in the water research program of the Environmental
Protection Agency, through in-house research and grants and
contracts with Federal, state, and local agencies, research
institutions, and industrial organizations.
Inquiries pertaining to Water Pollution Control Research Reports
should be directed to the Chief, Publications Branch (Water),
Research Information Division, R&M, Environmental Protection
Agency, Washington, D. C. 20460
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ANAEROBIC TREATMENT OF SYNTHETIC ORGANIC WASTES
by
J. C. Hovious
J. A. Fisher
R. A. Conway
Union Carbide Corporation
Chemicals and Plastics Division
Research and Development Department
South Charleston, West Virginia 25303
for the
OFFICE OF RESEARCH AND MONITORING
ENVIRONMENTAL PROTECTION AGENCY
Project #12020 DIS
January 1972
For sale by the Superintendent of Documents, U.S. Government Printing Office
Washington, D.C. 20402 - Price $1.75
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EPA Review Notice
This report has been reviewed by the Environmental
Protection Agency and approved for publication.
Approval does not signify that the contents necessar-
ily 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.
ii
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ABSTRACT
Bench, semi-pilot, and pilot-scale studies of three anaerobic treatment processes
have shown the anaerobic lagoon to be both the performance and economic choice
for pretreatment of petrochemical wastes in warm, spacious locations. Semi-pilot
scale studies of anaerobic contact digesters and packed-bed reactors indicated
performance problems when treating actual petrochemical wastes. Experimental
data from several sources were combined to prepare a design procedure for anaerobic
lagoon pretreatment systems.
Operation of a large (30 gpm) pilot plant consisting of anaerobic lagoons followed
by aerated stabilization and facultative ponds provided a BOD removal from the
petrochemical wastes of greater than 90 percent and a resistance to both organic-
loading and pH shocks. Comparison of an anaerobic-aerobic system with a strictly
aerobic system pointed out an economic advantage with the series system due to
lower sludge-disposal and oxygen requirements.
in
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CONTENTS
Section Page
I Conclusions 1
II Recommendations 3
III Introduction 5
IV Demonstration Scale Pilot Plant 15
V Anaerobic Lagoon 21
VI Aerated Stabilization of Anaerobic Effluent 61
VII Facultative Lagoons 73
VIII Overall System Performance and Special Studies 79
IX Lagoon Process Economics 87
X Alternatives Studied 101
XI Economic Analysis of Alternative Anaerobic Process 119
XII Acknowledgements 125
XIII References 127
XIV List of Publications 129
XV Glossary 131
XVI Appendix I - Pilot Plant Operating Data 135
XVII Appendix II - Experimental Methods and Apparatus 183
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FIGURES
No.
1 Biochemical Processes 9
2 Laboratory Contact Digesters H
3 Final An aerobic-Aerobic Demonstration System 16
4 COD Removal as a Function of Loading and Temperature 30
5 Relationship Between BOD and COD Removal 32
6 Organic Removal as a Function of Temperature 33
7 COD Removal as a Function of Loading 34
8 BOD Removal as a Function of Loading 35
9 COD Removal versus Areal Loading at 26 to 31°C 36
)
10 COD Removal as a Function of Loading and Temperature 38
11 Predicted Lagoon Temperatures in January, Houston- 39
Galveston Area
12 Lithium Profiles at Lagoon Influent 44
13 Lithium Profiles Near Lagoon Effluent 45
14 Digester for Bottom Solids Tests 47
15 Non-Photosynthetic Anaerobic Tests with Lagoon Sludge 49
16 Biological Activities at Various Lagoon Depths 52
17 Effect of Lagoon Depth on COD Removal and Sulfide Level 57
18 Aerated Stabilization Data, October-December, 1970 66
19 Aerated Stabilization Data, January-March, 1971 67
20 Aerated Stabilization Data, April-June, 1971 68
VI
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No. Page
21 Aerated-Stabilization Treatment of Anaerobic Effluent 69
Performance with Respect to Previous Semi-Pi lot Studies
22 Effect of Additional Aeration on Aerated Stabilization 71
Effluent
23 Relationship of Lagoon Feed and Effluent Solids Levels 75
24 Typical Removal Efficiencies for Anaerobic-Aerobic Systems 88
Basis - 100 Ib. BOD5 to Primary Clarifier,
800 mg/l Waste Strength
25 Variations in Cost with Waste Strength 95
26 Variation in Operating Cost with Waste Strength 96
27 Semi-Pilot Contact Digester 104
28 Effect of Retention Time on COD Removal in Laboratory 106
Contact Digesters
29 Removal vs Loading for Contact Digester Bench Scale Units 107
30 Semi-Pilot Scale Contact Digester Performance, Influent 109
and Effluent COD
31 Contact Digester, Efficiency at Various Loadings 110
32 Anaerobic Filters 111
33 Performance of Semi-Pilot Submerged Filters 114
34 Capital Cost Estimates, Anaerobic Treatment Processes 123
35 Capital Cost Estimates, Anaerobic Treatment Processes 124
36 Anaerobic Lagoon Performance, August-September 1970 136
VII
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No. Page
37 Anaerobic Lagoon Performance, October-December 1970 137
38 Anaerobic Lagoon Performance, January-March 1971 138
39 Anaerobic Lagoon Performance, April-June 1971 139
40 Hydrogen Sulfide Generator 192
41 Titration Curve 194
42 Anaerobic Pilot-Scale Reactor 200
VIII
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TABLES
No. Page
1 Typical Biological Treatment Reactions 7
2 Anaerobic Treatment Considerations 10
3 Anaerobic Systems Studied 12
4 Properties of Wastes Treated 17
5 Pilot Plant Analytical Schedule 18
6 Anaerobic Lagoon Study Periods 23
7 Anaerobic Lagoon Experimental Data 24
8 Performance of Lagoons at Two Depths 25
9 Anaerobic Lagoons Studied 26
10 Data from Union Carbide Pilot and Full Scale Studies 27
11 Data from EPA Sponsored Semi-Pilot Lagoon Studies 29
12 Removal of Specific Organics in Semi-Pilot Scale 41
Anaerobic Lagoons
13 Removal of Specific Organics in Pilot Scale Anaerobic Lagoons 42
14 Batch Decomposition in Bottom Sediments 48
15 Batch Photosynthetic Tests 50
16 Profile Data from Pilot Anaerobic Lagoons of Two Depths 54
17 Anaerobic Basin Profile 55
18 pH Shocks in Feed to Anaerobic Lagoon 59
19 Aerated Stabilization Analytical Summary 62
IX
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No.
20 Aerated Stabilization Performance Summary 63
21 Facultative Lagoon Summary 74
22 Profiles of Facultative Lagoons I and II 76
23 Facultative Lagoon Sludge Profile 78
24 Overall System Performance 80
25 Nutrient Analyses 81
26 Long Term BOD Data 82
27 Comparison of Long and Short Term BOD Removals 84
28 Major Assumptions of the Study 89
29 Anaerobic-Aerated Stabilization System, Summary of 90
Major Equipment
30 Construction Cost Summary, Anaerobic-Aerated 93
Stabilization System
31 Estimated Operating Cost, Anaerobic-Aerated 94
Stabilization System
32 Construction Cost Summary, Activated Sludge System 98
33 Cost Comparison, 10.0 MM Gal/Day Systems 99
34 Anaerobic Treatment of Synthetic Organic Wastes, 102
Mixed Chemicals - Digester Feed
35 Detected Constituents of Waste Used as Feed in Semi- 103
pilot Scale Studies
36 Laboratory Anaerobic Filter Studies on Dilute Waste 113
37 Removal of Specific Compounds in Contact Digestion Studies 116
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No. Page
38 Removal of Specific Compounds in Anaerobic Filter 117
Pilot Studies
39 Efficiencies of Three Processes in Specific Compound Removal 118
40 Summary of Wastewater Flows and BOD^ Concentrations 120
for Economic Comparisons
41 Design Parameters for Economic Comparisons 121
42 List of Major Assumptions for Economic Comparisons 122
43 Anaerobic Lagoon Data 140
44 Aerated Stabilization Data 149
45 Facultative Lagoon Data 158
46 Anaerobic Basin Profiles 167
XI
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SECTION I
CONCLUSIONS
1. In warm, spacious locations anaerobic lagooning has been shown as an
effective, economical process for pretreating petrochemical wastes prior to aerobic
stabilization in a 30 gpm pilot plant operated over a period of 11 months.
2. Anaerobic lagoon effluent fed to an aerated stabilization-facultative lagoon
process was treatable; a final effluent suitable for release to the environment was
produced. A dissolved oxygen residual of 1.5 mg/l was found to be necessary in
the aerated stabilization process.
3. The performance of anaerobic lagoons in organic removal was dependent upon
both the volumetric loading rate (Ib organic/unit volume-unit time) and the lagoon
temperature.
4. Lagoon performance decreased markedly at temperatures above approximately
43°Cand below 20°C.
5. Photosynthetic bacteria found to exist in the anaerobic lagoon could effective-
ly oxidize anaerobically produced sulfides. These bacteria also could utilize
volatile acids, but then exhibited a lower rate of sulfide oxidation. The lagoon
process was unique among the three alternatives in its tolerance of sulfates in the
feed.
6. Surface sulfide concentration was found to be dependent upon lagoon depth,
while BOD removal efficiency was only slightly dependent upon depth.
7, All influent volatile organic compounds identified chromatographlcally were
at least partially removed in the anaerobic lagooning process with the exception of
produced intermediates such as volatile acids. No chromatographically identifiable
materials were found in the effluent from the series system.
8. The increase in performance of anaerobic lagoons with decreased volumetric
loading was found to be due to greater removal of all identified influent constituents
rather than increased removal of any one.
9. The anaerobic-lagoon/aerated-stabilization/facultative-lagoon process was
found to have both performance and economic advantages over a completely mixed
activated sludge system.
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10. A design procedure was developed to apply the anaerobic pretreatment
process in a variety of situations.
11. Eleven-month operation of a large-scale pilot plant provided greater than
90 percent removal on a total-BOD5 basis and 95 percent removal on a soluble-
BOD5 basis.
12. The pilot plant was extremely stable with respect to pH and organic shock
loadings.
13. Degradation of biosolids in the facultative lagoons was found to be 56 per-
cent on a total suspended solids basis and 70 percent on a volatile suspended
solids basis.
14. Anaerobic filters and contact digesters provided satisfactory removals when
treating dilute wastes in bench-scale studies. Neither unit provided satisfactory
removals when tested on a semi-pilot scale with actual wastes.
15. The semi-pilot scale contact digester and anaerobic filter both provided
conversion of complex organics to volatile acid intermediates at levels comparable
to the anaerobic lagoons which were more efficient in removal of oxygen demand.
The difference in performance between the lagoon and filters and contact digesters
was due to the ability of the lagoons to metabolize produced volatile acids,
16. The anaerobic lagoon process was found to have the best performance and the
least cost of the three anaerobic alternatives considered (anaerobic lagoon,
anaerobic contact-digester, and submerged filter processes).
17. A series anaerobic/aerated-stabilization/facultative-lagoon system was
estimated to cost $0.034 per pound of BOD5 removed fora 10 mgd plant treating
an 800 mg/l BOD*; waste. The annual cost was approximately 25 percent investment
and 75 percent operating costs.
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SECTION II
RECOMMENDATIONS
1. In order to apply the anaerobic.process on a wider basis it would be
necessary to
a) Increase the allowable loadings in the anaerobic lagoon
process, and/or
b) Determine the cause and a remedy for problems encountered
with methane generation in the packed column and contact
digestion processes.
c) Investigate the performance of anaerobic lagoons having liquid
depth in excess of 12 feet.
d) Investigate the performance of anaerobic lagoons in locations having
colder climates than the project site.
The digester or filter process conceivably could be used as is for a pretreatment
approach in specialized locations with streams difficult to treat anaerobically by
utilizing their ability to convert complex materials to more readily degradable
intermediates. The loading to the anaerobic lagoon system conceivably could be
increased by determining the limiting step in the metabolic processes within the
system.
2. The study of organic compounds of low volatility which are not easily identified
(via gas-liquid chromatography) also is needed to determine whether these materials
can be removed by the anaerobic process. An example would be heavy organics
causing taste-and-odor problems in water supplies.
3. The value of the anaerobic processes could rest in properties other than oxygen
demand removal. Studies on difficult-to-degrade specific organics not identified
or not present in this study would be of value to determine those problem compounds
that can be degraded at least in part to materials more amenable to subsequent
aerobic treatment.
4. Further studies would also seem to be in order to delinate design parameters
for a flocculent system following the anaerobic step. Use of a flocculent system
could result in a cleaner effluent with no produced algae.
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5. Further studies are needed to determine the types and threshold concentrations
of compounds which inhibit anaerobic treatment. An initial project (^12020 PER)
to partially fulfill this need is now being conducted by the grantee under partial
sponsorship of the EPA Research, Development, and Demonstration rYograrm
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SECTION III
INTRODUCTION
The only practical tools now available for treating soluble organics in large volumes
of wastewater from a petrochemical plant are the aerobic biological systems, in
particular the activated sludge and aerated stabilization processes (1,2). This study
of anaerobic systems was undertaken to provide design engineers with an alternative
approach potentially avoiding some of the problems characteristic in aerobic treat-
ment and offering some performance improvements and economic advantages.
Difficulties encountered in the treatment of petrochemical wastes by conventional
aerobic biological systems have been described in some detail in reporting the
examination of a variety of treatment alternatives (3). One problem cited was the
characteristic elevated temperature of these wastes which was detrimental to micro-
organism flocculation and separation. Also, contained surfactants cause foaming
problems. The high temperature, surfactants, and the high rates of oxygen demand
due to the concentrated wastes result in oxygen transfer problems and usually dictate
the selection of long retention time and completely mixed systems in order to provide
sufficient aeration equipment. Even at longer retention periods, peak oxygen
demands often cannot be met with conventional equipment using air as a source of
oxygen. Some of the synthetic organic constituents have been cited as inhibitory
to nitrifiers (4), to protozoa, and possibly to flocculating organisms. The rapidly
varying types and quantity of organics discharged from a large petrochemical
complex result in non-equilibrium conditions in a high-rate biological process.
Even in a situation where an efficiently operating aerobic system can be provided,
the costs to aerate the system and to dispose of produced biological solids could
make anaerobic treatment an attractive alternative.
Encouraging results from lightly loaded anaerobic lagoon systems at various plants
and preliminary data in the literature attracted Union Carbide Corporation to conduct
further studies of anaerobic processes as they apply to petrochemical wastes.
Potential advantages of the anaerobic or combined anaerobic-aerobic process over
the aerobic process alone were identified in initial work. In order to increase the
scope of the study of anaerobic systems and to develop and disseminate the informa-
tion in a form useful to others, a research grant was awarded by the Office of
Research and Monitoring of the U. S. Environmental FVotection Agency for partial
support of in-depth anaerobic treatment studies by Union Carbide,
This report describes the anaerobic and aerobic treatment principles involved,includ-
ing the advantages and disadvantages of each, the process steps studied, the methods
and results used to select and develop an anaerobic treatment process for study in
a demonstration pilot plant, the results of the pilot studies, and an economic
evaluation of the selected system.
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TREATMENT PRINCIPLES
Although the stepwise chemical reactions for the intracellular metabolism of ^
organic chemicals by bacteria are complicated, more simple, over-all equations
familiar to chemists and engineers may be written that describe the initial
reactants and the final products (Table 1). The anaerobic reactions, known as
fermentation and anaerobic respiration, occur in closed reactors or in the bottom
of open lagoons and typically involve the reduction of carbon oxides, sulfates,
nitrates, and organic molecules (5). Typical empirical equations also are included
in Table 1 for photosynthetic processes and for the microbiological oxidation of
organic compounds in which molecular oxygen is the electron acceptor. The
biological cycles as they relate to the reactions listed in Table 1 are shown in
Figure 1.
Several important economic and technical advantages inherent in the anaerobic
treatment process are listed in Table 2 along with potential problem areas (6,7,8).
Significant savings can result if the anaerobic and aerobic processes are joined to
utilize the best features of each to compensate for some of their problems. This
usually would involve utilizing a roughing anaerobic treatment followed by an
aerobic treatment step for polishing of the wastewater.
Alternatives Tested
The first of three fairly well developed anaerobic processes selected for tests with
petrochemical wastestreams was the contact digester (9) or "anaerobic activated
sludge" system, Figure 2. The contact digester employs separation and recycle of
produced biological solids to increase the concentration of organisms and their
effective retention time within the digester. The increased organism retention time
compensates for the long generation times of the critical methanogenic bacteria,
The anaerobic trickling filter (10) was the second process selected for study.
Anaerobic filters utilize both the tendency of methane bacteria to grow on surfaces
and the filtering capacity of a flooded, packed bed to overcome the long generation
time of the methanogenic culture. The low solids production of the anaerobic
system slows filter clogging when a low solids feed such as a petrochemical waste is
treated.
The third anaerobic process selected for study was the anaerobic lagoon (11),
Anaerobic lagoons are a low rate system which operate at low suspended micro-
organism concentrations and therefore require a relatively long retention time for
adequate reduction of organic levels. The retention time required in a system is
primarily a function of temperature and the amenability of the waste constituents
to treatment by the various types of organisms involved.
Characteristics of the three systems studied are summarized in Table 3.
6
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TABLE 1
TYPICAL BIOLOGICAL TREATMENT REACTIONS
I. Anaerobic Non-Photosynthetic Reactions (molecular oxygen absent)
A. Nitrate Reduction (Denitrification)
5CH3COOH + 8NO3" > 10CO2 + 4N2 + 6H2O + 8OH"
5S + 6NO3" + 2H2O > 5SO4= + 3N2 + 4H+
B. Sulfate Reduction
2CH,CHOHCOOH + SO/* > 2CH-COOH + 2CO0 + H0S + 2OH"
o 4 o * f-
4H2 + SO4= ^ 2H2O + H2S + 2OH"
C. Organic Carbon Reduction (Fermentation)
CHLCOOH > CH,+CO9
O ^ £.
4CH3OH > 3CH4 + CO2 + 2H2O
C6H12°6 » 3CH3COOH
D, Carbon Dioxide Reduction
2CH3CH2OH + CO2 > 2CH3COOH + CH4
4H2 + C02 ^ CH4 + 2H20
4H2 + 2CO2 > CHgCOOH + 2H2O
II. Aerobic Non-Photosynthetic Bacterial Reactions
A. Oxygen-Li mi ted Systems
CH3CH2OH + O2 > CH3COOH + H2O
2CH3CHO+02 ^ 2CH3COOH
2CH3CHOHCH3 + O2~
(continued)
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TABLE 1 (continued)
II. Aerobic Non-Photosynthetic Bacterial Reactions (cont.)
B. Complete Oxidation
CH3COOH + 2O2 - > 2CO2 + H2O
> 2H2O
CH4 +2O2
+2H2O
C. Nitrification
2NH3 +3O2
2NO" +O
+
2NO2~ +2H +2H2°
» 2NO
D. Sulfur Oxidation
2H2S
» 2S + 2H2O
2S + 2H2O + 3O2
+
S2°3= + H2° + 2O2
4H
> 2SO= + 2H
E. Nitrogen Fixation
N« - > Nitrogenous Organics
III. Photos ynthetic Reactions
C02 +2H2S l!9ht > (CH20) + H20 + 2S
3C02 +2S +5H20
C02 + 2H20
9CH3COOH
3(CH20) +4 H
+
> (CH20) + H20 + O
^> 2C02+4(C4H602)+6H20
C02 + 2H2
2CH3COOH
> (CH20) + H20
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FIGURE 1. BIOCHEMICAL PROCESSES
Acetic
Propionic
Acids
Methane I
Anaerobic
Processes
(Lagoon depths)
Aerobic Processes
(Lagoon surface)
~~~. . Light
Light
Bacteria
Organics CO2/ H2O
(a)
(a) Possible gaseous emission to atmosphere
(b) Possible waste constituents
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TABLE 2
ANAEROBIC TREATMENT CONSIDERATIONS
I. Advantages of Anaerobic Processes
A. No aeration equipment is required for organic reduction, Associated
capital, power, and maintenance costs are avoided. System loading
is not limited by oxygen transfer.
B. Cellular material is produced in lower quantity and more stable form,
Savings in nutrients and in flocculants, equipment, and labor costs for
biomass dewatering and final disposal can be realized.
C. Some problem organic chemicals difficult to degrade aerobically will
degrade anaerobically.
D. The oxygen in nitrate and sulfate ions can be utilized for organic
oxidation.
E. Methane in off-gas potentially can be used for heating or in odor
control by incineration.
F. The anaerobic system can operate at temperatures at which a flocculant
aerobic system experiences biomass separation difficulties (3).
II. Potential Problems with Anaerobic Processes
A. High temperatures are needed for maximum rates.
B. High biomass concentration is required for reasonable rates at short
retention times.
C. Regeneration time for methane bacteria is long (2 to 11 days at 37°C),
thereby requiring long solids retention and acclimation times.
D. Methanogenic microorganisms are reportedly more sensitive to shock
loads, toxic materials, and environmental conditions.
E. Effluents low in BOD (<50 mg/l) with good aesthetic properties are
difficult to produce.
F. Produced gases are odorous if released.
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FIGURE 2
LABORATORY CONTACT DIGESTERS
Gas Pump
Mixer
Digester (5-gu!lcn)
Heating Mantle
Wet Test Meter or
Gas Collection
Bottles
Effluent
Receiver
Peristaltic
Sludge Recycle
Pump
Feed
*or Packed Column,
1-inch diameter
11
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TABLE 3
ANAEROBIC SYSTEMS STUDIED
Description
Flow pattern
Biosolids level
Metabolic pathways
Retention time
Gas collection
Temperature control
Submerged Filter
Rock or gravel
packed column
Plug flow
High biomass
through attached
growths
Fermentation and
anaerobic
respiration
1 to 3 days
Normally collected
Not normally
practiced
High biomass
through settling
and return
Fermentation
and anaerobic
respiration
Contact Digester Open Lagoon
Completely mixed Basin with con-
vessel siderable
stratification
Backmixed Some wind and
wave mixing,
thermal turn-
overs
Low suspended
solids, bottom
sludge layer
Fermentation,
anaerobic
respiration,
sulfur oxidation,
photosynthesis,
some aerobic
respiration
1 to 10 days 10 to 100 days
Collected Gas is released,
although a
plastic covering
with peripheral
collection tiles
is possible
Usually practiced Unfeasible unless
covered and
insulated
12
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SCOPE OF STUDY
The approach taken for the study was similar to that for chemical process develop-
ment: a literature survey, bench-scale studies of several anaerobic processes to
prove their feasibility under ideal conditions, semi-pilot studies of selected
processes under less ideal operating conditions, and finally large-scale piloting of
the best system. Economic evaluations were made concurrently to direct the
development toward the most feasible area. The end result was a design basis
for a large system for the anaerobic-aerobic treatment of petrochemical wastes.
Modifications of the three anaerobic processes were studied in bench-scale equip-
ment using a simulated petrochemical waste to determine process feasibility
with known, degradable substrates under well-controlled laboratory conditions.
The studies were performed in laboratories at the Union Carbide Technical Center,
South Charleston, West Virginia. The most promising systems were then tested
under less ideal conditions feeding actual petrochemical wastes. The tests with
real wastes under field conditions were originally planned for Union Carbide's
Institute Plant at Institute, West Virginia. However, periodic inhibition with the
wastes indicated a change in the study site and was the basis for the EPA Grant
Number 12020-FER " Identification and Control of Petrochemical Pollutants
Inhibiting the Anaerobic Processes. " The tests were therefore conducted at
Union Carbide's Texas City Plant to determine which of the processes worked best
under field conditions. The Texas City Plant wastes had been previously shown to
be amenable to anaerobic treatment in studies conducted by Union Carbide. The
field studies were made with concurrent economic studies and comprised the basis
for selection of one anaerobic process for testing in a large-scale unit. Large-scale
process selection comprised the first of three phases envisioned in the over-all
study.
The second phase was the design and construction of a pilot-scale demonstration unit
using the anaerobic process selected as superior. The third phase included operation
of the demonstration unit to optimize the process and to provide both economic and
design data adaptable for a large-scale (at least 500,000 gal/day) plant.
Pilot scale aerobic treatment studies were made on the effluent of the anaerobic
unit during the third phase, These studies provided information for designing and
estimating the cost of a total treatment plant combining the roughing anaerobic
treatment with the polishing aerobic treatment to produce a suitable effluent.
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Selection of Process for Demonstration Study
Based on the economic and technical feasibility studies, the anaerobic lagoon^
process was concluded to be sufficiently promising to test on a pilot scale. This
conclusion was based primarily on the following information obtained from the
preliminary studies.
1. The investment estimated for both the anaerobic contact and filter processes
exceeded that for the lagoon process at assumed favorable performance conditions
for all three processes. This relationship should hold for waste less degradable than
assumed in the estimates. The investment estimates assume land availability at a
reasonable price.
2, In semi-pilot studies neither the anaerobic filter nor the contact process
showed the reductions demonstrated in bench scale studies and assumed for the
conditions of the economic study. Therefore, from a performance and economic
standpoint they were even less attractive than the preliminary economic study
indicated.
3. The need for further development of the lagoon process on a small semi-pilot
scale was minimal, while considerable additional study on a semi-pilot scale
was needed before the contact and filter processes could be considered.
4. The lagoon process was unique in its tolerance of sulfates in the feed through
utilization of the sulfur oxidation-reduction cycle possible in the open-type
system. It benefits from both anaerobic and aerobic conditions at the different
levels in the lagoon.
5. According to the revised preliminary economic data the anaerobic-aerobic
process had lower annual costs than did the aerobic process alone, as was postulated.
Revised investment costs for both were similar (12).
6. Semi-pilot-scale studies of the aerated stabilization of anaerobic effluents
have shown the feasibility of the aerobic treatment step of a combined treatment
process.
7- The degradability of the Texas City Plant wastewater in open lagoons has been
repeatedly confirmed,
8. Land availability and mild cold weather conditions at the Texas City, Texas
location satisfy location requirements fora lagoon system.
14
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SECTION IV
DEMONSTRATION SCALE PILOT PLANT
The demonstration-scale pilot facility consisted of the selected anaerobic lagoon
process followed by an aerated stabilization process and facultative ponds for
aerobic effluent polishing, A line drawing of the experimental facility is
presented in Figure 3,
Two 50-by-100 foot anaerobic lagoons were used to determine the effect of depth
on the lagoon process. The deeper lagoon (12 foot) had a capacity of 450,000
gallons while the volume of the shallower lagoon (6 foot) was 225,000 gallons.
When operating at a 15-day retention time approximately 30 gpm of pretreated
(clarified and neutralized) waste was fed to the two lagoons.
Aerated stabilization was accomplished in a 31,000 gallon open lagoon equipped
with a surface aerator which accepted only a portion of the effluent from either
lagoon. A flow of approximately 7 gpm was required to provide the desired 3-day
retention time.
Two facultative lagoons each 6-feet deep and of 21,000 gallons' volume were
used to settle effluent solids from the aerated stabilization basin and provide a
polishing treatment.
The petrochemical waste treated in the pilot system was made up of the dilute
waste from the Texas City Plant of Union Carbide Corporation. At times this
dilute waste was supplemented with effluent from a long-retention-time lagoon
system treating concentrated wastes and with the concentrated feed to this system.
Properties of the wastes treated are described in Table 4.
The sampling and analytical schedule followed during the pilot study is listed in
Table 5. Where composite samples are indicated the sample was collected in an
iced container over the period of compositing. All samples were preserved by
refrigeration between sampling and analysis.
The anaerobic lagoon demonstration system was operated to identify problems
associated with scale up of the semi-pilot data, to determine the effects of depth
on performance, and to provide design parameters. Aerobic units were operated to
prove treatability of anaerobic effluent and to provide a design basis for economic
comparison of the anaerobic-aerobic series process with completely aerobic systems.
15
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FIGURE 3
FINAL ANAEROBIC-AEROBIC DEMONSTRATION SYSTEM
Anaerobic Lagoons
(10- 15 day retention)
(225,000 and 450,000 gallons)
Aerated Stabilization
(2-3 day retention)
(30,000 gal Ions)
Facultative Lagoons
(1.2 to 2 day retentions)
(21,000 gallons each)
Feed:
Neutralized
Nutrients Added
BOD"22 700 mg/l
COD~ 1300 mg/1
6ft
Anaerobic Lagoon
Cross Section
50ft
50ft
(100ft long)
12ft
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Property
Temperature, °C
BOD, mg/l
COD, mg/l
Alkalinity, mg/l
as CaCOg
Total Carbon,
mg/l
PH
S04=, mg/l**
Specific Volatile
Organics
TABLE 4
PROPERTIES OF WASTES TREATED
Dilute Waste
35-55
400 - 800
700- 1600
200 - 400
6- 11
200 - 300
See Tables
12 and 13
Concentrated Lagoon
Effluent
Ambient
600- 1000
3000
4500
2500*
8-9
Very low (20)
Acetone
Methyl ethyl ketone
Methyl isobutyl
ketone
Volatile acids
Concentrated Lagoon
Feed
Ambient
4000 - 7000
15,000
4000 - 6000
7-9
600 - 700
Those present in
dilute waste with the
addition of
Acetaldehyde
Prop ionic acid
Butyric acid
Pentanol
Gj-aldehydes
Cc-acids
CQ-alcohols
Phenol
Butyl ethers
Propyl ethers
Methyl isobutyl
ketone
^10-18 a'cori°ls+
Formate"*"
* Total organic carbon, 1200 mg/l
+ Known to be present but not specifically identified
** Approx. 200 mg/l added from 1^504 required for
neutralization
17
-------
00
TABLE 5
PILOT PLANT ANALYTICAL SCHEDULE
Type Analysis
pH
Feed
M, G,
Anaerobic Lagoons
Basin Effluent
East West East West
COD (unfiltered and filtered)
BOD5 (unfiltered) C3
BOD5 (filtered)
Volatile acids C3
Alkalinity C3 G,
Total suspended solids C3
Volatile suspended solids C3
Total organic carbon O
Sulfur (S=, SO4=) SC3
Phosphates SC3
Nitrogen (NH4+, NO2~, NO3~) SC3
BOD2Q (total) . SC3
Dissolved oxygen
Oxygen uptake
Microscopic examination ~ E
Specific organics (GLC) SC3
Total nitrogen (Dohrmann) O
Profile . ~ P
Temperature G, G]
Aerated
Stabil.
Effluent
O
SG,
SG,
SG,
sc3
--
sc3
0
O
SG,
SG,
sc3
SC3
O
O
SG,
SG,
SG,
SG,
Gl
Gl
E
SG,
0
Facultative Lagoons
Basin
East West
Effluent
West
G3
G3
O
SG3
SG3
SG3
SGo
so,
GI
Gl
(continued)
-------
TABLE 5 (continued)
S = Four special one week studies during period of steady operation.
P = Depth and horizontal profiles of D.O., pH, ORP, Temp,, 504s, S=, COD.
Unscheduled (3 or 4 times during test period).
E = Microscopic examination for viable organisms and identification of types as
required. Unscheduled.
M = Controlled or monitored continuously.
Cg = Three-day composite of 24-hour samples (refrigerated).
G, = Grab daily.
C^ = Daily continuously composited sample.
O = Readings taken occasionally during course of study.
Go = Composite of 3 daily grab samples (refrigerated).
-------
SECTION V
ANAEROBIC LAGOON
The anaerobic lagoon system, due to its open surface, provides an environment
suitable for not only the strictly anaerobic processes which occur in the contact
digester and anaerobic filter but also facultative, photosynthetic, and aerobic
processes at the surface. The wide variety of reactions possible is illustrated
previously in Figure 1. Within the anaerobic depths illustrated at the extreme left
of the figure, the classical acid-formation/methane-fermentation reaction steps are
observed. The role of inorganic electron acceptors such as nitrate and sulfate in
anaerobic respiration is depicted. In addition, some petrochemical waste components
such as low molecular weight acids and alcohols may enter the cycle at an intermed-
iate point and be converted directly to methane. The lagoon surface also provides
an environment in which photosynthetic bacteria and algae may proliferate. Near
the lagoon surface microaerophillic and facultative bacteria may utilize surface-
entrained and photosynthetically produced oxygen in aerobic stabilization of
organic wastes and inorganic reduced forms such as sulfides.
Two aspects of the complex biochemical relationships are of particular interest in
petrochemical waste lagooning. Bacteria which are able to utilize volatile acids
are important as these are generally present as components of the waste as well as
produced metabolically within the system. If such bacteria were not present, the
system acidity would increase, overcoming the buffer capacity and failure due to
low pH would be certain. Bacterial groups of consequence in volatile acid meta-
bolism are the classical methanogenic group and the photosynthetic purple sulfur
and non-sulfur bacteria. Another potential mechanism for removal of volatile acids
is aerobic oxidation in surface layers.
A second aspect of particular interest includes those bacterial and chemical
reactions which comprise the lagoon sulfur cycle. In an uninhibited anaerobic
system, influent sulfates will be reduced to sulfides with stabilization of organics.
However, no net reduction in oxygen demand will take place unless the produced
sulfides are either oxidized, lost to the atmosphere, or precipitated. Organisms
which oxidize reduced sulfur forms are important both in reduction of oxygen demand
and in maintaining a low level of sulfides, which would otherwise create serious
odor problems and could be toxic to algae and methanogenic bacteria (13,14). The
photosynthetic purple sulfur bacteria and microaerophillic sulfur bacteria are two
bacterial groups which act to control sulfides, while atmospherically entrained and
photosynthetically produced oxygen can chemically oxidize sulfides.
21
-------
The characteristics of anaerobic photosynthetic purple sulfur bacteria of the family
Thiorhodaceae have been documented in standard textbooks in terms of ability
to oxidize both sulfide and stored elemental sulfur to sulfate, uptake of organic
materials, atmospheric nitrogen fixation, and proper environmental conditions for
maximum growth. The seasonal variation of interactions between methane
bacteria, purple sulfur bacteria, and algae in a lagoon treating domestic waste-
water also has been studied (14).
Demonstration Lagoon Performance
During operation of the demonstration system a wide variety of both routine
analytical determinations and special studies were performed both in the anaerobic
segment and around the entire system. Experimental periods as segmented for
temperature or loading conditions are itemized in Table 6 while routine operating
and environmental data for the lagoons are presented in Table 7 and performance
data are included in Table 8. Daily operating data for the entire system are included
in Appendix I. A graphical presentation of performance indicating break points in
feed and temperature is also included in Appendix I.
Lagoon performance was found to vary both with temperature and with volumetric
loading rate (Ib organic applied/unit volume-time) to the system. Some variation
with the depth of the lagoon also was observed at higher loading rates.
As the demonstration study was operated over a relatively narrow range of loading
conditions, data on performance in organic removal has been combined with the
semi-pilot data collected in this study and data collected by Union Carbide from
previous pilot and full scale lagoon studies for analysis. Combination of the data
provides for prediction of lagoon performance under a wide range of conditions,
and hence, wider applicability.
Experimental data utilized originate from lagoons ranging in size from 50 gallons
(190 liters) to 450,000 gallons (1,700,000 liters) while full scale data originate
from lagoons from 26 million to 180 million gallons. Lagoon volumes, waste
strengths, nominal depths, and detention times are included in Table 9while
loading and removal data are included in Tables 8, 10, and 11.
The effectiveness of the lagoons in removal of oxygen demand was correlated with
volumetric loading rate (Ib waste/1000 cu ft-day) and temperature. In addition,
an attempt was made to correlate removal with area I loading (Ib waste/acre-day)
for one temperature range. The effect of volumetric loading and temperature on
COD removal is illustrated in Figure 4, while the observed relationship between
22
-------
TABLE 6
ANAEROBIC LAGOON STUDY PERIODS
Date
8-10 to 10-8-70 Dilute waste feed> warm temperature
10-9 to 11-2-70 Dilute waste feed, cooler temperature
11-3 to 2-7-71 Dilute waste feed, cold temperature
2-8 to 3-10-71 Dilute waste + previously treated anaerobic waste feed,
cold temperature
3-11 to 4-14-71 Dilute waste + previously treated anaerobic waste feed,
cool temperature
4-15 to 5-11-71 Dilute waste + additional concentrated feed, cool
temperature
5-12 to 6-7-71 Dilute waste + additional concentrated feed, warm
temperature
6-8 to 6-30-71 Dilute waste + additional concentrated feed, warm
temperature
23
-------
Food
TABLE 7
ANAEROBIC LAGOON EXPERIMENTAL DATA
No. 1 Lagoon, Deep
No. 2 Logoon, Shallow
Date
8-10 to 10-8-70
10-9 to 11-2-70
11-3 to 2-7-71
2-8 to 3-10-71
3-1 1 to 4-14-71
4-15 to 5-11-71
5-12 to 6-7-71
6-8 to 6-30-71
pH
6.7
6.9
6.7
7.0
6.7
6.5
7.0
6.5
Temp.,
°C (a)
41
40
39
33
32
35
37
40
CODr
(b),
mg/l
1120
1120
990
970
1140
1780
1600
2000
BOD
(d),
mg/l
460
550
480
420
550
640
790
1180
Volatile
Acid,
mg/l as
HAc
199
133
151
160
213
360
376
686
pH
7.5
7.4
7.3
7.0
7.2
7.3
7.1
7.1
Temp . ,
°c
30
25
20
17
21
24
27
29
CODT
(b),
ma/I
560
530
580
660
730
1030
930
1130
CODF
(c),
mg/l
460
360
520
610
660
920
830
1070
BOD
mg/l
170
150
180
210
280
370
440
600
Volatile
Acid,
mg/l as
HAc
205
269
184
232
238
359
465
686
Alkalinity,
mg/l as
CoC03
591
520
456
389
601
769
827
942
Temp. ,
pH °C
7.8 29
7.6 25
7.4 19
7.1 17
7.3 20
7.5 24
7.3 27
7.3 29
CODT
(b),
mg/l
530
530
580
600
670
860
830
1010
CODF
(c).
mg/l
480
380
500
550
570
800
770
920
BOD
W),
mg/l
160
180
190
190
230
270
410
480
Volatile
Acid,
mg/l as
HAc
184
199
173
222
225
309
441
622
Alkalinity,
mg/l as
CoCOj
634
639
482
386
602
793
833
99.1
(a) Neutralization pit
(b) CODT - Total COD
(c) CODF - Filtered COD
(d) BOD - Total, 5 day BOD
-------
TABLE 8
PERFORMANCE OF LAGOONS AT TWO DEPTHS
(a) lb/1000 eu ft-doy x 16 « g/eu m-doy
(b) Total COD
KJ
Oi
Pwlod
8/10- 10/8/70
10A- 11/2/70
11/3/70-2/7/71
2/fc - 3/10/71
3/11-4/14/71
4/15-5/11/71
5/12 - 6/7/71
6/6 - 6/30/71
Tvmp.,
c
30
25
20
17
20
24
27
29
Feed Concentration,
mg/l
BOD
460
550
4SO
420
550
640
790
1180
COP OQ
1120
1120
990
970
1140
1780
1600
2000
Loading,
lb/1000 cu ft-doy (a)
BOB COD (b)
2.0
2.4
2.1
1.8
2.4
2.8
3.4
5.1
4.9
4.9
4.3
4.2
4.9
7.7
7.0
8.7
Loading, Ib/A-day
Deep
BOD
1050
1250
1080
945
1245
1450
1790
2670
COD
2290
2300
2280
2190
2570
4025
3633
4530
Shallow
BOD
525
625
705
470
620
.725
890
1335 ,
COD
1150
1150
1140
1095
1285
2010
1815
2265
Removals, percent
Deep Lagoon
BOO COD (b)
64 50
74
62
50
48
42
44
49
53
41
32
36
42
42
43
Shallow Lagoon
BOD
65
67
60
54
58
59
49
59
COD (b)
53
53
41
37
41
51
48
50
Difference
Shallow-Deep, %
BOD
1
-7
-2
4
10
17
5
10
COO
3
0
0
5
5
9
6
7
-------
TABLE 9
ANAEROBIC LAGOONS STUDIED
Seadrift Plant
Foil-Scale
Approximate
Location
Texas City Plant
Full -Scale
Pi lot -Study
Lagoon
Volume, gal (a)
26,000,000
110,000,000
50(e)
5,500 (e)
225,000(b,e)
450,000(c,e)
Waste Strength, i
COD
8500
6000
1300-15,000
1200-3400
900-2000
900-2000
ma/I
BOD
4500
3000
500-5800
500-1600
400-1200
400-1200
Approximate
Retention, days
30
125
4-40
5-15
15
15
Depth, ft
1.5
3.5
3
3 (d)
6
12
180,000,000
600
45
(a) gal x3.785 - liters
(b) 6-feet (1.8 m) depth, 50 x 100-feet (15 x 30 m) surface
(c) 12-feet (3.7 m) depth, 50 x 100-feet (15 x 30 m) surface
(d) Computed as volume/surface area
(e) Part of 12020-DIS project
-------
TABLE 10
DATA FROM UNION CARBIDE PILOT AND FULL SCALE STUDIES
Lagoon
Texas City Plan*
Volume, gal.
26,000,000
Texas G ty Plant 110,000,000
SeadrSft Plant
180,000,000
Temperature
°C
~
__
--
28
22
16
24
29
Waste Strength,
mg/l
BC>D
4510
4440
5500
2990
2685
2280
536
527
598
547
641
COD
8450
8440
5900
5960
4450
__
Volumetric Loadings,
Ib/lOOOcuft-day
BOD
9.4
9.2
6.6
0.88
0.78
1.2
0.76
0.92
1.1
1.4
1.3
COD
17.3
17.3
1.7
1.7
2.2
--
Areal Loading,
Ib/A-day
BOD
665
640
460
133
120
175
132
160
188
237
228
COD
1200
1200
262
265
340
Removal, %
BOD
33
39
58
66
63
65
75
75
69
76
83
COD
30
31
46
42
29
__
Texas City Plant
50
27
21
31
13
8
30
20
43
48
31
27
20
31
1360
1420
1300
1310
1410
1270
1385
1295
1410
1240
1330
1380
1245
8.8
9.2
8.4
8.5
9.2
8.3
8.9
8.4
9.2
8.0
8.6
9.0
8.1
960
1000
920
930
1000
900
970
915
996
877
938
975
881
56
50
60
38
30
54
46
48
23
57
43
46
56
(continued)
-------
TABLE 10
(continued)
Lagoon
Texas City Plant
Volume, gal.
5500 (a)
00
Waste Strength,
Temperature, mg/I
°C
23
30
27
23
28
28
28
26
19
15
10
17
13
19
22
13
19
22
23
28
29
BOD
580
550
490
680
630
1053
1480
1080
1080
1080
925
1390
1540
1500
1620
1390
1050
810
1040
1230
COD
1200
1100
1230
1260
1260
1620
2150
1930
2000
2160
2160
2160
3080
3400
3240
3000
3000
2300
1740
3020
3080
Volumetric Loadings,
Ib/lOOOcufr-day
BOD
3.8
3.6
3.2
4.4
4.1
14.0
12.0
7.0
7.0
7.0
6.0
9.0
10.0
13.0
7.0
6.0
5.0
7.0
9.0
8.0
COD
7.8
7.1
8.0
8.2
8.2
10.5
28.0
25.0
13.0
14.0
14.0
14.0
20.0
22,0
28.0
13.0
13.0
10.0
15.0
26.0
20.0
Areal Loading,
Ib/A-day
BOD
490
470
415
575
540
1830
1570
920
920
920
785
1175
1310
1700
915
785
655
915
1175
1045
COD
1020
930
1050
1075
1070
1370
3660
3270
1695
1830
1830
1830
2615
2875
3660
1700
1700
1310
1960
3400
2615
Removal, %
BOD
47
73
76
67
73
30
20
45
48
43
54
34
40
52
46
52
68
62
62
54
COD
24
42
52
53
52
50
30
19
37
42
40
45
30
33
37
32
37
49
45
38
42
(a) Lagoon of an irregular, prismoid shape. Effective depth computed as volume/surface area.
-------
TABLE 11
DATA FROM EPA SPONSORED SEMI-PILOT LAGOON STUDIES
Lagoon
Texas City Plant
Volume
50
Waste
Strength,
Temperature, mg/l
«c
15
15
14
14
14
BOD
5800
5800
COD
14,600
14,600
1,490
1,480
1,380
Volumetric Loading,
lb/1000
BOD
18.8
9.4
cu ft-day
COD
47.5
22.2
24.4
12.1
11.3
Area! Loading,
Ib/A-day
BOD
2050
1030
COD
5175
2420
2660
1320
1230
Removal, %
BOD
18
34
--
COD
18
23
26
34
34
Texas City Plant 5500
15
685 1,510 5.8
12.8
760 1675
36
29
-------
FIGURE 4
COD REMOVAL AS A FUNCTION OF LOADING AND TEMPERATURE
COD Removal, %
T 100
90
80
*lb/1000cuffx 16 =
30
-------
BOD and COD removal is shown in Figure 5, Efficiency is seen to be highest at
warmer temperatures and light loading;rates and,to decrease with either a temper-
ature drop or a load increase. Figures 6-8 indicate the performance variation
resulting from changing one variable while the other variables are held constant
and illustrate the fit of the data points about BOD and COD removal lines.
Figure 6 indicates that removal efficiency decreases above a maximum temperature
of approximately 43°C at a loading of 8-9 Ib COD/1000 cu ft-day (130-140 g/cu
m-day)D Temperatures were varied by artifically heating or cooling reactors and
therefore do not necessarily represent actual conditions in a Gulf Coast location.
In Figures 7 and 8 the effect of varying loading on performance in terms of COD
and BOD removal respectively is illustrated.
A correlation between area I loading and COD removal at a temperature of 26 to
31 °C is presented in Figure 9. A particular discrepancy is noted between removals
from the twelve foot deep pilot system and the 5500 gallon semi-pilot lagoon at
loadings of approximately 3500 Ib COD/A-day, Areal loading is related to
volumetric loading as
Areal Loading (Ib/A-day) = Volumetric Loading (lb/1000 cu ft-day)
(43.56)(Depth,ft).
Since the deep pilot scale system had a depth of four times that of the semi-pilot
lagoon a volumetric loading four times larger must have existed in the semi-pilot
lagoon for an equal areal loading. The large reduction in performance in the semi-
pilot lagoon correlates well with the volumetric loading plot (Figure 7). Due to
the discrepancies observed in comparing data using an areal loading correlation
and the good agreement with volumetric loading, the volumetric loading rate was
selected as a design parameter.
Since a given volumetric loading may occur from a number of combinations of
waste strengths and retention times, the source of the data used in this study needs
to be defined. The maximum loading rates in Figure 4 were obtained using
concentrated wastes in 20- and 40-day retention 50-gallon reactors. These same
wastes are treated acceptably in actual lagoons of longer retention time (lower
loading rate) at the Texas City Plant. Minimum loading rates were observed with
dilute wastes in retention times from 5 to 15 days and concentrated wastes in
extremely long retention ponds.
Fora given volumetric loading rate the large differences in hydraulic retention time
due to varying waste strengths result in changes in surface cooling during the
critical winter periods. For example, at the same volumetric loading a concen-
trated waste is retained longer than is a dilute waste; and the increased retention
31
-------
FIGURES
RELATIONSHIP BETWEEN BOD AND COD REMOVAL
80
1
J
o
O
co
70 -
60
50 -
40
30 -
20
10 -
A 50 gallon reactor
V 5500 gallon reactor
a Large scale pilot data
20 30 40
COD Removal, %
32
-------
FIGURE 6
ORGANIC REMOVAL AS A FUNCTION OF TEMPERATURE
100
CO
CO
8
BOD (2^4 lb/1000 cu ft-day)
O 50-pallon reactor
O 5500-ga I Ion reactor
&
reactors
COD (8-9 lb/1000 cu ft-day)
24 28 32
Temperature, °C
-------
FIGURE 7
COD REMOVAL AS A FUNCTION OF LOADING
CO
50-gallon reactor
5500-gallon reactor
225,000 &450,000ngallon reactors
U-16°C
28-31°C
18 22 26 30 34
Loading, Ib COD/1000 cu ft-day
-------
FIGURE 8
BOD REMOVAL AS A FUNCTION OF LOADING
Q
O
O 50-gallon reactor
A 5500-gallon reactor
Seadrift Plant data
Q 225, 000 & 450, 000 reactors
Loading, Ib BOD/1000 cu ft-day
40
20
-------
FIGURE 9
COD REMOVAL VERSUS AREAL LOADING AT 26 TO 31 °C
/v
60
50
#
V
I 40
&
a
<-> 30
20
10
i
V
7A
A
jO
A->
V
V 5500 gallon semi-pilot lagoon
A 6- foot deep pilot lagoon
O 12-foot deep pilot lagoon
o
V
V. .. ,
V
O
1
500 1000 1500 2000 2500 3000 3500 4000 4500 5000
Areal Loading, Ib COD/A-day
-------
retention results in a lower temperature and a consequent depression in performance.
Relationships between loading, temperature/ and resultant removals, therefore/ must
be considered for use of the curves in design. Figures 10 and 11 provide a method of
evaluating various alternatives for a desired removal.
In Figure 10 the three-dimensional Figure 4 is reduced to a topographic plot of
constant removal with temperature and loading. The area under the constant
percentage removal line incorporates temperature and loading conditions that
represent a removal of that level or greater. The lengths of line presented for each
removal level indicate the limits of available data from this study. As lower
temperatures and loadings are most generally critical/ the curves define the area of
greatest interest.
Application of these relationships would typically start from a known waste strength
with an estimation of volumetric loading. The associated retention time and lagoon
volume are computed from Equations I/ 2/ and 3.
. .. ,, x Influent concentration (mg/l) x 62.4 ,.x
Retention (days) = v -g/ (1)
Desired loading (lb/1000 cu ft-day) x 103
_ Influent concentration (mg/l) ,«
Desired loqding (gm/cu m-day)
Volume (gal) = HOW (gaJ/
-------
00
^
f
3
O
cf
O
«J
I
a
1
10
45
FIGURE 10
COD REMOVAL AS A FUNCTION OF LOADING AND TEMPERATURE
40
35
30
25
Temperature, °C
15
10
-------
FIGURE 11
PREDICTED LAGOON TEMPERATURES IN JANUARY, HOUSTON-GAL VESTON AREA
30
eo
o
26
U 22.
%
S
I '8
I
J
u
10
Assumed Conditions
10-foot depth (3.8m)
50°C waste temperature
13.3 miles/hour average wind (21 lcm/hr)and
1030 Btu/sq ft^day sunlight (2800 kg-cal/
sq m-day)
75 percent! le dew point temperature 4°C
2000 3000 4000 5000 6000 7000
Influent COD Concentration, mg/l
8000
9000
10,000
-------
The following example illustrates the utility of the developed relationships. Cooling,
equalization, and a 50 percent minimum BOD removal are required prior to aerobic
treatment for a 3 mgd (11,000 cu m/day) flow containing 3000 mg/l COD at a Gulf
Coast location near Houston, Texas. Also assume that influent sulfates are low so
that the lagoon system may be constructed reasonably deep, about 10 ft (3 m).
Relating to Figure 5 to obtain a BOD removal of 50 percent a COD removal of 40
percent would be reasonable in design. Figure 10 indicates that such a removal
could be met at the following loading-temperature conditions:
Loading, Ib COD/ Required
1000 cu ft-day Temperature, °C
10 14
15 17
20 21
Examination of Figure 11 for an actual temperature at the three loadings indicates
that at the 20 lb/1000 cu ft-day (320 g/cu m-day) loading, the required minimum
temperature of 21 °C just can be maintained while at the two lower loadings, a
temperature warmer than required and hence, larger removals would occur. Such
a loading would require a retention time of
3000 mg/l x 62.4
-* =9.4 days
20 Ib/lOOOcu ft-day x 103
or a lagoon of approximately 9 acres (3.6 ha) would be required at the assumed
10-ft (3 m) depth. Assuming the lagoon maintained approximately ambient
temperature in the warmer months a removal of approximately 45 percent COD
(60 percent BOD) would be expected (Figure 5).
Although gross performance parameters are of interest in overall design, the utility
of the lagooning process in removal of specific materials is needed when determining
its applicability to any given waste stream. Removal of specific volatile organic
compounds from lagoons receiving petrochemical wastes has been monitored by gas
chromatographic techniques for two lagoon loading rates with a concentrated waste
(15,000 mg/l COD), for one loading with a dilute waste (1500 mg/l COD) and for
the demonstration system. As presented in Tables 12 and 13, the more lightly loaded
of the systems treating concentrated waste (22 Ib COD/1000 cu ft-day) provided a
slightly lower effluent concentration of virtually all the detected influents and less
volatile acids than did the more heavily loaded system (48 Ib COD/1000 cu ft-day)
The lagoon treating dilute wastes (13 Ib COD/1000 cu ft-day) showed an average '
reduct.on m detected materials, excluding acetic acid, of about 60 percent The
lagoons treating dilute wastes contained none of the produced propionic and butyric
ac.ds wh.ch were observed in the concentrated system, possibly due to different
40
-------
TABU 12
REMOVAL OF SPECIFIC ORGANIC* IN SEMI-PILOT SCALE ANAEROBIC LAGOONS
Dilute Wastes
1 3 Ib COD/1000 eu ft-day
Influent (mg/1)
Compound
Methonol
Ethonol
n-Propanol
Isoproponol
n-Butanol
Isobutonol
bopentanol
Hexanol
Acetaldenyde
n-Bvtyroldehyde
rsobutyraldehyde
Acetone
Methyl ethyl
ketone
Benzene
Ethylene glyeoi
Acetic ocld
Proplonic acid
Butyric acid
Mean
80
80
~
60
--
30
60
15
10
135
215
Max
134
134
134
~
101
89
30
11
232
300
Min
40
38
17
_-
18
32
8
5
103
100
Number of
Occurrences
10
11
11
-_
14
11
10
10
11
10
Mean
35
15
_
30
_
10
_
39
8
5
30
220
Effluent (mg/1)
Max
67
19
_
84
_
18
_
48
8
5
39
500
Min
13
10
..
17
~
9
..
~
16
8
5
26
75
Number of
Occurrences
7
6
_
11
..
_.
7
_.
- ~
10
7
6
6
11
Mean
380
270
170
175
170
250
315
140
80
190
210
100
-
755
2120
0
0
Concentrated Wastes
Influent (mg/1)
Max
400
480
584
376
246
711
735
355
92
450
450
128
1420
3440
Min
294
144
33
125
77
77
162
71
46
68
98
80
387
1000
_
Number of
Occurrences
8
6
5
9
7
8
9
9
9
7
7
9
9
9
9
9
22 Ib COD/1000 cu ft-day
Effluent (mg/1)
Mean
135
120
35
45
75
80
70
20
35
50
50
53
155
2280
505
330
Max
187
144
84
84
123
139
88
36
92
112
75
80
322
3380
824
448
Min
107
48
17
42
38
31
44
21
18
22
22
40
77
1300
196
96
Number of
Occu rrences
7
7
5
7
4
4
4
4
5
5
5
7
-
6
7
7
7
48 Ib COD/1000 cu ft-day
Effluent (mg/1)
Mean
145
130
40
55
80
85
100
30
40
35
50
47
190
2620
470
300
Max
200
144
84
84
116
123
184
71
92
75
75
80
387
4000
772
320
Min
120
96
17
42
62
38
59
14
18
15
15
40
-
103
1400
185
128
' Nunberof
Occurrence*
9
9
6
8
4
4
8
6
5
6
7
8
8
9
7
6
Note: Data are averaged from 5 to 12 occurrences in grab or composite tqmplei.
Average temperature for all systems 15°C
Depth of lagoons treating concentrated waste was 3 ft, 2.5 ft for dilute watte
Detention times were 40 days (22 Ib COD/1000 cu ft-day), 20 days (48 Ib COD/1000 cu ft-day)
and 7.5 to 10 days (13 Ib COD/1000 cu ft-day).
-------
TABLE 13
REMOVAL OF SPECIFIC ORGANICS IN PILOT SCALE
ANAEROBIC LAGOONS
Effluent
Influent
Compound, mg/l
Mefhanol
Ethanol
n-Propanol
Isopropanol
Acetaldehyde
Acetone
Methyl ethyl ketone
Benzene
Ethyl acetate
Ethylene glycol
Acetic acid
Prop ionic acid
Mean
74
in
25
28
24
31
15
6
9
124
140
31
Max
107
230
58
58
37
48
22
10
9
168
188
31
Number of
Min Occurrences Mean
53
38
17
17
18
16
8
5
9
77
112
31
12
12
10
7
3
12
4
9
5
12
12
1
" 27
12
8
10
4-
14
7
4v
4~-
26
118
16
Deep Lagoon
Max
27
19
8
17
24
7
~
26
125
21
Number of
Min Occurrences Mean
27
10
8
8
8
7
--
26
62
10
1
4
1
3
~
9
2
~
1
6
2
27
10
4-
8
4-
11
7
4-
4-
26
122
10
Shallow Lagoon
Max
27
10
8
16
7
26
175
10
Number of
Min Occurrences
27
10
8
8
7
26
25
10
1
5
4
9
2
1
7
1
4- Compound not detected in lagoon effluent
Deep lagoon 12 feet deep
Shallow lagoon 6 feet deep
Detention time = 15 days
Temperature ranged from 17 to 30°C
-------
wastes. Analysis of removal data on an unsteady feed could be misleading since the
effects of feed dilution into a large volume/ weathering, and concentration are not
taken into account. However, based on the five to twelve occurrences in the
composite and grab samples collected, all of the detected materials except meta-
bolic intermediates such as volatile acids appear to be removed to a significant
degree in the anaerobic lagoon pretreatment process.
Mixing and Tracer Studies
A tracer study was made in the deeper pilot lagoon to determine Whethefi,short
circuiting, leakage, or vertical liquid stratification would be d prbbleffHitt S)«tem
operation or scaling. The tracer results also provide a measure of the equalization
capacity of the lagoon.
A lithium tracer was added to the deep lagoon feed as a spike on December 22, 1970,
The winter period was selected for testing since the potential for thermal stratifica-
tion and short circuiting (maximum temperature differential between waste, 40°C
temperature, and lagoon contents, 14 to 22°C) should be greatest. Initial samples
were collected at 0.1, 6, and 11 foot depths near the lagoon inlet at intervals of
1, 3, 6 and 24 hours after dosing. Samples were also collected at 0.1, 3, and
11 foot depths near the lagoon effluent at intervals of 1, 3, 5, 7, 9, 13, and 16
days. Lithium profiles with time are presented in Figures 12 and 13.
Profile data at the lagoon inlet indicate a rapid rise in lithium concentration at
the 0.1 and 6 foot depths near the inlet. No peak in concentration was seen at the
sludge layer. After a 9 hour period the concentration had attained a uniform level
at all three depths indicating complete vertical mixing. Data collected near the
effluent show that a uniform vertical distribution was present. The, tim|,o|.prfi(val
of the peak concentration was approximately 4 days at the 6 foot dep|^g||1ef fhe
extended shape of the tracer curve indicates longitudinal distribution, approaching
a completely mix condition after 5 to 6 days' retention.
Analysis of the water in the shallow lagoon and surrounding the deep lagoon
indicating a maximum concentration of 0.1 mg/l lithium compared to the 1 to 2
Tig/I level in the lagoon.
Functional Tests
A number of experiments have been made to estimate the impact of various microbial
groups on lagoon performance and to trace hydraulic properties within the demonstra-
tion lagoon. Emphasis was placed on volatile acid and sulfur metabolism. Two
techniques were used in studying the influence of various cultures on lagoon
performance.
43
-------
FIGURE 12
LITHIUM PROFILES AT LAGOON INFLUENT
Concentration, mg/l
o i\> w
JUi H-H.G
Dose
: /v_
2M
i i
12N 12M
12/22
i i
12N 12M
12/23
i;
*. £ 1
i
-3 S
'
12M
12N
12/22
6-feet
2M
12N
12/22
12M
12N
12/23
12M
11-feet
12M
I
12N
12/23
12M
44
-------
li"
FIGURE 13
LITHIUM PROFILES N.EAR LAGOON EFFLUENT
Surface
12/20 21
Ji
22 23 24 25 26 27 28 29 30 31 1/1
Data
3ft
23456
I I I r
12/20 21 22 23 24 25 26 27 28 29 30 31 1/1 2 3 4 5
.r
3 S
Date
11 ft
i I
j I i I I
12/20 21 22 23 24 25 26 27 28 29 30 31 1/1
Dale
2345
-------
Continuous experiments were performed in the two large experimental lagoons
constructed under the demonstration phase of the project. During the 11-month
duration of the study diurnal profiles of sulfur compounds, COD, volatile acids,
pH and temperature occasionally were made.
Batch studies of both methanogenic and photosynthetic activities were made by
innoculating waste or synthetic substrates with biota from the demonstration lagoon
system and incubating the mixture under either the original or an artificially
imposed environment. In the case of methanogenic studies, 1,5 liters of bottom
sludges were mixed with 1.5 liters of waste or waste and dilution water to a 1.51
volume in a one-gallon (3.8 liters) container as illustrated in Figure 14. Gas was
collected by displacement in an inverted graduated cylinder. The reactor contents
were mixed daily,and samples were withdrawn at various intervals for analysis of
total soluble COD, soluble organic COD (sulfides removed by acidification and
nitrogen stripping), total carbon, total organic carbon, sulfates, sulfides, volatile
acids, and pH. Bottom sludge reactors were incubated at ambient temperature.
Batch tests of photosynthetic activity were made by filling a standard 300-ml BOD
bottle with 240 ml of lagoon liquor from the desired level and test material,
dilution water, or a combination to bring the total volume to 300 ml. One half of
the prepared samples were covered with aluminum foil to maintain a dark condition.
Samples were then incubated under ambient temperature conditions either in a
continually lighted bath for studies of maximum photosynthetic activity or within
the lagoon for studies under actual conditions. Analyses were performed for the
same parameters as during methanogenic studies with the exception that in photo-
synthetic tests sampling was destructive.
Results
Data obtained in methanogenic studies for various waste loadings and reactor
charges are summarized in Table 14, while the soluble organic COD and volatile
acid levels are plotted in Figure 15. Initial soluble organic COD uptake was found
to be very rapid, with the rate dependent upon initial COD level. Inhibition as
evidenced by both decreased removal rate and increased volatile acid levels was
noted at an added loading level of 35 Ib COD/1000 cu ft (560 g/cu m). In all
systems except the one showing inhibition, the rapid COD uptake was followed by
a period of uniform removal which was equal in all systems. Gas production lagged
behind COD uptake and was most rapid during this uniform uptake period.
Data obtained in two batch photosynthetic studies are presented in Table 15.
Examination of the first study which involved incubation in unlimited light conditions
indicated that photosynthetic sulfide oxidation occurred with samples from the
surface and from within the lagoon depths. The oxidation progressed to sulfate at
low but measurable sulfide levels as evidenced by the increase in sulfate levels in
the light-incubated samples. The increase in sulfate levels would also discount
46
-------
FIGURE 14
DIGESTER FOR BOTTOM SOLIDS TESTS
Septum for application
of vacuum to reset gas
collector
Gas collection by displacement in
inverted graduate
Low pH water to keep CC>2 in gas
Tubing clamp - closed except when collecting sample
Vacuum for
sample
collection
I-gal glass bottle containing
3 liters of liquid mixed 2~3 times/
week
Test tube for sample collection
47
-------
TABLE U
BATCH DECOMPOSITION IN BOTTOM SEDIMENTS
00
Charge Added,
Ib COO/1000 eu
(a)
0
9
21
31
35
ft
Day
0
3
7
15
33
0
3
7
15
33
0
3
7
15
33
0
3
7
15
33
0
3
7
15
33
Total (b)
Organic
Carbon,
mg/l
100
70
70
100
45
125
100
80
135
75
145
120
95
110
55
215
170
100
90
65
250
250
200
115
80
Soluble (b)
COD,
mg/l
330
195
170
220
180
470
255
270
220
200
670
370
340
250
225
830
405
360
260
245
890
705
630
350
285
Soluble (c)
Organic Volatile
COD,
mg/l
315
210
160
200
170
435
275
210
220
200
560
390
280
260
225
750
430
290
245
215
755
715
565
340
290
Acids,
mg/l as HAc
72
36
24
24
12
24
24
24
24
24
120
120
84
92
24
48
84
48
36
12
84
230
190
150
24
PH
7.5
7.3
7.2
7.0
7.5
7.3
7.2
7.0
7.0
7.8
7.5
7.2
6.9
7.0
7.8
7.2
7.2
7.0
7.0
7.7
7.1
7.4
6.9
7.1
7.8
Cumulative
Gas, ml
0
Nil
20
48
~
0
Nil
62
85
0
Nil
108
137
0
Nil
138
273
0
Nil
121
325
Sulfide,
mg/l, S'
5
Nil
Nil
Nil
Nil
5
5
5
Nil
6
5
Nil
5
Nil
26
5
Nil
5
Nil
6
5
5
5
10
Nil
Sulfate,
mg/l, 504
20
75
100
100
175
Nil
30
20
60
80
35
30
Nil
50
75
25
Nil
Trace
60
35
100
20
Nil
10
65
Notes: (a) All reactors contain 50% by volume lagoon bottom sludge. In addition the reactors contain dilute
and concentrated wastes to provide the quoted volumetric loadings and tap water to bring the
volume to 100%.
(b) Filtered.
(c) Pilfered, acidified, nitrogen sparged to remove sulfides.
(d) Units were incubated at ambient temperature (25-30°C).
-------
o
O
u
JO
FIGURE 15
NON-PHOTOSYNTHETIC ANAEROBIC TESTS WITH LAGOON SLUDGE
900
800 X
600
400
200
Charge
Ib COD/1000 cu ft
8 12
Incubation Period, days
16
Charge
IbCOD/lOOOcuft
-O I
50-
4 8 12
Incubation Period, days
49
-------
TABLE 15
BATCH PHOTOSYNTHETIC TESTS
Oi
o
Lagoon
Seed
Source
Study 1 -
0.5-foot
3-foot
6-foot
Study 2 -
0.5-foot
3 -foot
Incubation
Conditions (a)
Optimum lighting
L
D
L
D
L
D
L
D
L
D
L
D
Natural lighting,
L
D
L
D
Additives
Sulfide Level,
mg/l
Initial Finaf
, 7-day incubation in
None
None
1 g/l NaAc
1 g/l NaAc
None
None
1 g/l NaAc
1 g/l NaAc
None
None
1 g/l NaAc
1 g/l NaAc
30
30
30
30
30
30
30
30
30
30
30
30
laboratory
9
73
37
78
<5
78
31
92
<5
82
33
92
15-day incubation submerged in
20% waste (c)
20% waste
20% waste
20% waste
24
24
25
25
15
72
75
70
Sulfate Level,
mg/l
Initial
320
320
320
320
325
325
325
325
320
320
320
320
lagoon
170
170
155
155
Final
355
165
270
145
310
285
290
115
375
155
295
120
110
Nil
Nil
Nil
Soluble Organic
COD (b), mg/l
Initial
485
485
1610
1610
465
465
1610
1610
460
460
1630
1630
875
875
900
900
Final
370
395
1440
1630
360
396
1400
1590
340
415
1340
1630
435
780
690
700
Volatile Acids
as HAc, mg/l
Initial
205
205
1175
1175
180
180
1160
1160
180
180
1175
1175
265
265
275
275
Final
36
120
850
1110
24
120
865
1110
36
120
815
980
60
530
370
385
(a) Both light (L) and dark (D) covered bottles were incubated at ambient temperatures (25 to
(b) Sulfides removed by acidification and sparging with nitrogen gas.
(c) Bottle makeup 60 ml of waste (1000 mg/l COD) plus 240 ml lagoon liquor.
30°C).
-------
oxidation by molecular oxygen which would result primarily in sulfite or thiosulfate
production (16'). Less sulfide oxidation occurred in the presence of higher acetate
levels; however, a net oxidation did occur as evidenced by the difference between
the light and dark bottles. Increased COD removals and volatile acid uptakes were
also observed in all lighted samples. Apparently the organisms responsible for the
photosynthetic effect are present both at the surface and at a considerable depth in
the lagoon.
The data from the second study, in which the samples were returned to the lagoon
for incubation under ambient, diurnal light and temperature conditions, indicate
that near the lagoon surface the photosynthetic culture is quite active. A large
uptake of both soluble organic COD and volatile acids in the diurnally lighted
bottle in excess of that in the dark system is indicative of the amount of photo-
synthetic effect present in the surface layers. In spite of the fact that a decrease
ih sulfides was observed, no increase in sulfate was noted indicating either that the
sulfur was stored internally or that it'was potentially oxidized by a mechanism other
than bacterial photosynthesis. At the three-foot depth no significant difference was
noted between the lighted and dark samples. Apparently light transmission was not
sufficient for photosynthetic activity at this depth. A plot of the influence of various
microbial groups on the lagoon system as derived from the batch tests is illustrated
in Figure 16.
The influence of depth on the contributions of the various microbial groups to over-
all lagoon performance may be estimated by assuming plug flow through the lagoons
and no vertical mixing. If a zone of influence of two feet is assumed for the photo-
synthetic and sludge zones and removals in a 15-day detention time system are as
evidenced in the batch tests illustrated in Figure 16, then removals of 30 and 40'
percent soluble organic COD would be expected in the 12- and 6-foot (3.7 and
1.8m) lagoons, respectively. As liquid is free to move from one area to another in
an actual lagoon as shown in the tracer studies, the vertical mixing would act to
temper the influence of depth on performance, particularly with the rapid initial
uptake rate evidenced in the sludge layers.
The actual influence of depth was measured by both environmental profiles and
performance in the two continuously fed experimental lagoons. Since the two pilot
systems had identical top and bottom surface areas, an equal amount of atmospheric
oxygen entrainment, photosynthetic activity, and bottom activity could be assumed.
Both lagoons were also operated at the same volumetric loading rate and detention
time. Differences in performance as listed in Table 8 should be directly relatable
to the relative volume of the less active lagoon mid-depths.
51
-------
FIGURE 16
BIOLOGICAL ACTIVITIES AT VARIOUS LAGOON DEPTHS
1000
O Sludge Reactor
(Table 14, 21 Ib
COD/1000 cu ft
loading)
8 10 12 14 16
Incubation, days
52
-------
The experimental data indicate that at lower volumetric loading rates no significant
difference in performance existed. As loading increased, the shallower lagoon
provided up to a 9 percentage point increase in COD removal (17 percent increase
in BOD removal). Although the magnitude of the performance difference is
approximately that predicted from batch tests, the absolute COD removal is greater.
The effect of depth became pronounced when residual surface sulfide levels and
profiles were examined. Averaged profile data are presented in Table 16, a typical
profile in Table 17, and results of all profiles in Appendix I. The typical profile
in Table 17 indicates the deeper lagoon maintained a surface sulfide level 3 to 4
times that in the shallower lagoon in the afternoon period and 4 times the shallow
lagoon in the early morning. As would be expected from the batch photosynthetic
studies, the sulfide profile increased from a minimum at the surface to a maximum at
the sludge water interface. A tendency was also noted toward lower volatile acid
and organic levels near the sludge in agreement with the rapid uptakes of these
parameters observed in batch determinations. A lower concentration of total and
filtered COD, total organic carbon, and volatile acids was also noted at all points
in the shallower lagoon.
Averaged data for all profiles indicated that the 12-foot lagoon system maintained a
surface sulfide concentration of 1.6 times that in the 6-foot lagoon (25 vs 40 mg/l)
with both receiving feed sulfate levels of 400 to 500 mg/l. Effects of depth on both
COD removal and sulfide concentration are summarized in Figure 17, which in-
corporates data from a 50-gallon reactor (2.5 foot depth) operating at a similar
loading and temperature. While overall COD removal changed only 11 percentage
points with a four-fold increase in depth, the surface sulfide level increased by a
factor of two. The greatest increase in sulfides occurred between the 6- and 12-foot
depths, while little difference was seen between 2.5- and 6-foot depths. Depth
becomes important in design of a system where sulfates are present in the feed at high
levels.
In practical application lagoon depth selection is tempered by soil conditions,
available land area, land costs, and performance requirements as well as sulfate
load. The pretreatment function of the lagoon system in waste equalization, cooling,
removal of a significant portion of influent oxygen-demanding materials, and re-
moval of inhibitory materials may be satisfied without the maximum removal possible
in the system.
Operating Observations
One point which has been cited as an advantage of the lagoon system for petro-
chemical waste treatment is its ability to treat the rapidly varying effluent from a
typical petrochemical facility with long term stability. The eleven-month operation
of the demonstration lagoons provided considerable evidence of stable operation.
53
-------
TABLE 16
PROFILE DATA FROM PILOT ANAEROBIC LAGOONS OF TWO DEPTHS
Surface Sulfide, mg/l
Doily Mean, COD, mg/l (a) 4 a.m. .
Date
10-1-70
10-8-70
10-29-70
1-13-71
2-17-71
3-17-71
Mean
12 ft
656
610
570
649
607
518
6ft
492
507
440
585
526
420
12ft
56
45
.68
17
19
42
41
6ft
33
33
43
0
5
J4
25
4 p.m.
12ft
51
39
59
26
17
J4
38
6ft
27
31
41
11
5
.11
24
(a) Average soluble organic COD measured at 6-16
points in lagoon at various depths.
Feetx 0.3048 = meters
54
-------
I. 4:30 p.m. 2/17/71
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
TOC, mg/l
VA, mg/l as HAc
SS/VSS, mg/l
S", mg/l
SO4/ mg/l
pH
ORP, mv
Temp., °C
CODT/CODF, mg/1
TOC, mg/l
VA, mg/l as HAc
SS/VSS, mg/l
S", mg/l
SO4, mg/l
TABLE 17
ANAEROBIC BASIN PROFILE
Influent, Deep Basin
Effluent, Deep Basin
Surface
7.0
-300
24
685/580
205
216
44/28
15-
380
3ft
6.8
-305
24
690/585
205
240
42/22
20
375
6ft
6.7
-300
24
700/595
210
264
50/30
23
360
Sludge
6.8
-300
24
655/595
200
264
40/16
47
290
Surface
6.9
-300
24
635/580
195
264
42/22
19
375
3ft
6.9
-310
24
675/565
180
278
54/32
18
380
6ft
6.9
-310
24
630/560
180
278
44/24
16
370
Sludge
6.9
-290
23
670/580
185
264
48/24
38
300
Influent, Shallow Basin
Surface
7.0
-280
23
635/540
170
192
54/32
5
380
3 ft
7.0.
-280
23
620/505
165
204
50/32
5
410
6ft
7.0
-300
23
615/440
160
240
66/36
29
305
Effluent, Shallow Basin
Surface
7.1
-290
23
615/380
160
228
50/32
5
380
3ft
7.1
-300
23
615/400
165
240
48/34
5
385
6ft
7.1
-310
23
640/420
165
264
84/48
21
290
(continued)
-------
TABLE 17 (continued)
II. 4:30a.m. 2/17/71
Parameter
PH
ORP, mv
Temp., °C
COD-r/CODp, mg/l
TOC, mg/l
VA, mg/l as HAc
SS/VSS, mg/l
S=, mg/l
, mg/l
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
TOC, mg/l
VA, mg/l as HAc
SS/VSS, mg/l
S=, mg/l
SO., mg/l
North Section of I
South Section of I
Surface
6.8
-310
23
740/645
180
230
30/22
19
335
North
Surface
7.0
-320
20
645/630
185
288
35/26
5
370
3 ft
6.8
-300
21
740/680
170
230
28.24
17
355
Section of II
3ft
6.9
-300
21
680/630
205
264
38/32
5
370
6ft
6.8
-340
20
725/655
160
240
26/21
19
350
6ft
6.9
-280
21
655/630
210
230
37/32
5
365
Sludge
6.8
-340
20
715/630
195
192
23/18
32
275
Surface
6.8
-310
21
740/670
170
230
29/21
19
335
Soutfi
Surface
7.0
-280
21
690/600
195
216
38/31
5
360
3ft
6.8
-320
21
740/645
210
278
30/25
16
360
Section of II
3ft
7.0
-300
21
665/610
195
230
37/29
8
375
6ft
6.8
-330
20
705/645
200
336
28/20
15
350
6ft
7.0
-320
20
690/530
180
264
104/61
19
330
Sludge
6.9
-340
19
695/585
205
264
26/20
31
280
-------
FIGURE 17
EFFECT OF LAGOON DEPTH ON COD REMOVAL AND SULFIDE LEVEL
*
Q
o
60
50
40
30
20
10
8-9 Ib COD/1000 cu ft-doy, 29-30°C
O 6 and 12 ft experimental facility
rj 5500 ga I Ion reactor (effective
depth computed as volume/
surface area)
50
10
678
Lagoon Depth, ft
10
11
12
-------
Examination of the influent-effluent COD graphs (Appendix I) indicated that many
times during the course of operation the influent COD levels would at least double.
As the feed samples analyzed were composite samples over a 3-day period, the
instantaneous levels were undoubtedly much greater in the on line system without
equalization. In no case did the influent variation cause problems in lagoon
operation. With the exception of one spill, the influent peaks were diluted and
subsequently degraded without an increase in effluent level.
Due to failure of the feed pH control equipment, the lagoon was also subjected to
many pH shocks. Examples of maximum and minimum levels experienced are
indicated in Table 18. Obviously the lagoon is very insensitive to short duration
(5 to 6 days) of acid feed (4 to 5) or to shorter periods (3 days) of basic feed
(9 to 9.5).
One reason for the ability of the lagoon to withstand an acid feed is the presence of
volatile acid salts in the influent. Biological decomposition of the volatile acid
segment releases undissociated cations which result in increasing system alkalinity.
For example, an overall reaction for decomposition of sodium acetate yields an
increase in biocarbonate alkalinity as
CHgCOONa + H2O *> CH4 + NaHCOg
This phenomena was so prevalent in the demonstration lagoons that a lagoon feed
pH of 6.5 to 7.0 resulted in lagoon pH range of 7 to 8. In all cases (Table 8) an
increase in pH through the lagoons was noted.
58
-------
TABLE 18
PH SHOCKS IN FEED TO ANAEROBIC LAGOON
Date
September 2, 1970
7
9
January 10, 1971
11
12
February 8, 1971
28
March 8, 1971
9
10
28
29
30
31
April 1, 1971
7
8
9
TO
11
12
May 1, 1971
2
3
4
5
16
17
18
19
20
21
22
23
24
25
26
27
pH(a)
8.8
2.3
Duration,
days Resulting Effect in Lagoon
1 None
1 None
2.1 1 None
5.1 1
5.6 > 3 None
5.2 J
3.8 1 Slight pH dip, immediate recovery
3.0 1 None
9.5
9.2
9.0 .
4.5
4.6
4.6
5.2
4.9 -
5.2
4.8
5.2
4.8
4.8
4-2
4.8 '
5.6
4.4
2.7
5.2 _
5.0 ~
2.4
5.0
5.8
4.3
5.3
3.1
5.9
9.1
5.8
4.5
5.6
3 None
P
5 None
6 None
* 5 None
Lagoon 1 pH dropped from pH 7.5
> before low pH feed to 6.2 on
May 23rd, recovered on 25th with
no effects
59
-------
SECTION VI
AERATED STABILIZATION OF ANAEROBIC EFFLUENT
In order to provide the additional treatment required prior to release of an
anaerobic effluent to the environment, an aerated stabilization process was selected
for the demonstration-scale study. Aerated stabilization was chosen due to a pre-
viously reported problem (3) in maintaining a flocculent bacterial population in a
conventional, complete-mix activated sludge system with the varying winter-summer
feeds from an anaerobic lagoon.
The aerated-stabilization process calls for less critical operation and can accept
varying applied loads since it does not rely on maintenance of conditions required
by the sensitive floe-forming bacteria. The aerated stabilization system was follow-
ed by two facultative lagoons primarily for solids removal, storage, and de-
composition.
The aerated stabilization process is a high-rate lagooning operation employing a low
concentration of non-flocculent bacteria which are synthesized during bio-
oxidation of the organics and are discharged with the effluent. Given a proper
environment and lack of toxicants, the performance of an aerated stabilization process
is limited by one of two factors. If the system is not operated at a positive oxygen
level, then removal is dependent upon the quantity of oxygen supplied. If oxygen is
maintained above some level where performance is independent of oxygen concen-
tration, then retention time for bacterial growth and resulting assimilation of waste
products is the limiting mechanism. If the rate of liquid flow through the reactor and
resulting detention time is less than the time required for stabilization, only a portion
of the waste will be removed. As the detention time becomes large, near equilibrium
stabilization is reached. Based on previous studies performed by Union Carbide (3) a
retention time of three days was selected for the demonstration aerated stabilization
study.
Performance
Data obtained as grouped for temperature, loading, and other test conditions are
presented in Table 19/while performance and daily operating data are presented in
Table 20 and Appendix I, respectively.
In addition to normal temperature and loading variations, a study of controlled
dissolved oxygen levels was made. Also, additional more-concentrated wastes were
added to both the anaerobic and aerobic units to increase the loading level.
61
-------
TABU 19
AERATED STABILIZATION ANALYTICAL SUMMARY
Efflmnt
Data
10-1 to 11-3-70
1 1-4 to 1 1-22-70
11-23 to 12-17-70
12-18-70 to 1-3-71
1-4 to 1-11-71
1-12 to 2-4-71
2-5 to 2-15-71
2- 16 to 3-9-71
^ 3-10 to 4-14-71
a-
10 4- IS to 5-27-71
5-28 to 6-30-71
pH
7.4
7.4
7.2
8.1
8.1
8.2
7.0
7.0
7.2
7.2
7.1
T.mp.
26
21
20
21
14
20
16
18
21
25
29
CODj
528
496
659
731
730
828
648
672
727
991
1070
CODp
349
396
581
-
-
-
610
614
660
890
991
TSS
102
83
78
-
-
~
57
58
55
67
86
VSS
75
54
40
~
~
~
43
39
43
54
61
BOD
148
130
224
216
283
325
216
196
287
386
582
VA
261
215
60
-
-
-
180
247
236
386
659
Alk
557
483
413
686
728
696
438
380
597
793
903
PH
7.6
7.6
7.7
7.8
8.4
7.8
7.7
7.2
7.6
8.0
7.2
T«mp.
22
17
19
19
10
17
13
17
19
23
26
DO
4.1
1.0
4.9
4.5
5.4
4.2
7.4
4.7
3.8
4.1
4.1
CODT
264
444
383
445
557
428
374
343
430
522
488
COD,;
184
306
266
306
444
230
181
234
267
246
275
TSS
54
138
138
222
184
220
198
174
156
283
254
VSS
42
87
95
155
121
169
161
134
134
246
212
BODT
44
95
74
72
145
94
59
53
85
104
95
SODp
-
69
-
90
64
26
28
33
30
37
Alk
474
448
344
528
578
386
264
210
414
583
609
* Not* - Will in toot* COIM fa* Ih* lain* at anaerobic lagoon fTlu»nt
Unlti are a «a>mwd In Tabli 7.
Nom
Low DO
-------
TABLE 20
AERATED STABILIZATION PERFORMANCE SUMMARY
Loading,
Ib/lOOOcu ft-day Percent Removal Oxygen Uptake Oxygen Required
Dote
10-1 to 11-3-70
1 1-4 to 11-22-70
11-23 to 12-17-70
12-18 to 1-3-71
1-4 to 1-11-71
1-12 to 2-4-71
2-5 h> 2-15-71
2-16 to 3-9-71
3-10 to 4-14-71
4-15 to 5-27-71
5-28 to 6-30-71
BOD
3.1
2.7
4.7
4.5
5.9
6.8
4.5
4.1
6.0
8.0
12.1
COD
10.9
10.3
13.7
15.2
15.2
17.2
13.5
14.0
15.1
20.6
22.2
BODj
70
27
67
67
49
71
73
73
70
73
84
BODp
~
~
69
~
68
80
88
86
89
92
94
CODy
50
10
42
39
24
48
42
49
41
47
54
CODF
47
23
54
70
62
60
72
72
mg/l-hr
Low DO
~
3.7
2.8
6.9
8.6
8.4
Ib Oxygen/lb BODR
~
~
~
~
1.5
1.5
2.6
2.3
1.3
-------
In order to determine the limiting oxygen level an 18-day study was performed
(November 4 to November 22, 1970) in which the oxygen level was controlled at
a 1 mg/l concentration. During the prior and subsequent operation periods the
over-sized aerator was not controlled and the oxygen level was generally at a
4 mg/l level or above. During the controlled period the aerated stabilization basin
became dark and odorous. A large decrease in removal of total BOD and totd and
filtered COD was also noted. Such a performance decrease was unexpected with
1 mg/l residual DO as many aerated stabilization units operate successfully with'
no measurable oxygen residual although they may suffer some performance decrease.
The presence of a dissolved oxygen residual was verified by using both the Winkler
titration and a polarographic probe, so the basin was by definition "aerobic" in
spite of odors. Determinations made during this period also indicated nil soluble
sulfides and a low level of reduced iron present in the system which would contribute
to the high residual BOD and COD.
Chen and Morris (16) have indicated the oxidation of sulfide by molecular oxygen to
be a complex series of reactions with rate and end products dependent upon sulfide
level, oxygen level, and catalysts present. Conceivably, the lower oxygen Jevel
present during the low oxygen study could result in incomplete conversion of sulfides
and a resulting end product such as sulfite, thiosulfate or elemental sulfur detectable
in the BOD and COD tests. Each of these compounds were analyzed in the COD
determination at concentrations of 1000 mg/l to determine whether it would result
in a significant oxygen demand as measured by the COD technique. Results indicated
that while elemental sulfur was insoluble and only slightly oxidized, sulfide and
thiosulfate were 87 and 77 percent oxidized, respectively. The presence of partially
oxidized sulfur forms rather than incomplete carbon removal could have contributed
to the performance decrease.
Overall oxygen requirements were determined by monitoring the oxygen level with
time in a 300-ml BOD bottle filled with the system mixed liquor. Due to the stressed
conditions which existed periodically in the aeration basin, a definite correlation
of oxygen requirements was difficult. The data do indicate that conceivably more
than one pound of oxygen per pound of BOD removed was required.
i
The oxygen level was raised (11/23/70 - 12/16/70) following the low oxygen test,
at which point BOD removal increased to the 67 percent level confirming that
oxygen level was the controlling factor. Operating observations indicated that a
DO residual of 1.5 mg/l was necessary to avoid problems.
During the period of December 18, 1970 to February 4, 1971, effluent from an
anaerobic lagoon treating concentrated waste was added to the aerated stabilization
feed to provide a higher organic feed level and to determine whether a concentrated
waste could undergo further stabilization after long-term (approximately one year)
anaerobic lagooning. The initial study period (December 18 to January 3) indicated
64
-------
no operational problems and organic removals comparable to performance without the
additional feed. However, between January 4 and 11,0 brief cold snap and a high
pH resulting from the alkaline concentrated anaerobic waste resulted in decreased
BOD and COD removals. Addition of sulfuric acid to the aeration basin provided an
increase in removals to previous levels.
Between April 15 and June 30, 1971, a concentrated waste was added to the
anaerobic lagoon to bring the overall waste strength to 1000 mg/l BOD. The in-
creased loading to the anaerobic system resulted in a higher loading to the aerobic
lagoon. As discussed in the anaerobic lagooning section, a high system pH (8.0)
accompanied decomposition of the waste high in salts of volatile acids. Inhibition
was indicated at this pH as evidenced by both decreased oxygen uptake and high
organic residual during peak loadings as may be seen in examination of Figures
18-20. From the oxygen uptake data inhibition apparently occurs at pH levels
greater than about 8.0. Neutralization with sulfuric acid (May 28 to June 30, 1971)
restored system performance to normal.
Loading and Retention-Time Effects
The percentage of organic material removed in aerated stabilization has been found
to be dependent upon the influent organic concentration. Because the efficiency of
the prior anaerobic lagooning step is temperature dependent, the aerated-stabilization
process will receive a varying load. Performance in the aerated-stabilization process
at various influent loads must be evaluated to predict the effluent quality. A
previously developed (3) BOD removal loading curve for a 3-day aeration time
together with the removal data collected in this study are presented in Figure 21.
Removals of BOD are near equal to or better than those reported in small-scale
studies except for periods of imposed stress (high pH or low DO).
Examination of the per forma nee-1 cod ing curves indicates that BOD removal is a
function of volumetric loading (Ib BOD/1000 ft^-day) for the three-daydetention
time. The increase in reduction efficiency with loading is in agreement with the
theory of complete-mix, continuous-culture systems which predict an effluent
concentration of the limiting substrate which is independent of influent concentration
under steady-state conditions. At higher loadings, a greater efficiency removal
would then be obtained as influent concentration increased and effluent concen-
tration remained approximately constant. A difference in removal of approximately
10 percent was noted between winter and summer operation. The absolute
difference could be due to temperature influence on the predominant biological
culture or to different products in the anaerobic lagoon effluent. For example, the
anaerobic system could produce a more stabilized waste in the summer periods with
less contained volatile acids and a more complete breakdown of complex influent
wastes.
65
-------
FIGUM 1»
ABATED STABILIZATION DATA, OCTMBt-OtCEMSt, 1970
OCTOMft
NOVEMMK
MCXMMT
-------
900 r-
FIGUXE If
ABATED STABILIZATION DATA, JANUAIY-MAtCH, 1
t:
JANUARY
FEMUARY
MARCH
-------
ASUTtOSMilUZAIIONDATA. AXIL-JUNE, 1971
O
00
5 10 13 *> IS »
20
JUNE
-------
100
90
80
70
_- 60
j 50
Q
eo 40
30
20
10
0
FIGURE 21
AERATED-STABILIZATION TREATMENT OF ANAEROBIC EFFLUENT
PERFORMANCE WITH RESPECT TO PREVIOUS SEMI-PILOT STUDIES
dissolved oxygen study
I I
3-day retention time, hot
-3-day retention time,
cold
Demonstration plant performance
^ Semi-pilot study performance
10 "15 20 25
Organic Loading, Ib BOD/1000 ff3- day
30
35
-------
To confirm that a 3-day aeration period was sufficient for virtually complete^
degradation, samples were taken from an aerated stabilization system operating
at a 3-day detention and aerated in a batch degradation test under ambient
conditions for up to 8 additional days. Samples were obtained daily from this
batch test. The results presented in Figure 22 indicate no additional degradation
with longer aeration periods using samples collected under non-upset conditions.
70
-------
FIGURE 22
EFFECT OF ADDITIONAL AERATION ON AERATED STABILIZATION EFFLUENT
11/1/70 Sample
c- 100
Q
O
I ' ', ' i
5 6 7 8 '
11/24/70 Sample
(spill in system)
12/11/70 Sample
a
O
150
c- 100
50
O
O
Days
-------
SECTION VII
FACULTATIVE LAGOONS
In many instances the effluent from the aerated-stabi lization process needs to be
clarified before release to receiving waters as these biological solids can contribute
0.2 to 0.5 Ib BOD5/lb solids released. Because the produced biosolids are non~
flocculent and consequently settle at a slow rate, a conventional clarifier may be in-
efficient in removal. Facultative lagoons were selected in the demonstration
facility to provide a long retention time and large area for solids separation and
for subsequent storage and anaerobic decomposition of the solids. Two lagoons in
series were designed for the demonstration facility, each of a six-foot depth and
providing two days' retention .
Operating and BOD-removal data for the facultative lagoons are presented in
Table 21. The lagoons were able to provide a total BOD removal of 40 to 50 per-
cent except for the period of low dissolved oxygen in the prior aerated stabilization
unit. The removal was primarily through solids sedimentation as evidenced by the
relatively low soluble BOD reductions. A system effluent of less than 50 mg/l total
BOD was noted except during stressed periods of aerated-stabilization operation.
The performance of the lagoons in solids removal is summarized in Figure 23. The
best fit line indicates a net "removal" of approximately 60 percent of the applied
volatile and suspended solids. The removal was expressed on a net basis as the
primary constituent in the effluent was visually noted to be produced algae while
the influent contained primarily bacteria.
A profile of environmental parameters within the facultative lagoons is reported in
Table 22. A dissolved oxygen residual is noted at all points with the maximum
concentration at the effluent. Minor sulfide concentrations also were noted and are
indicated by the low oxidation reduction potential in spite of the oxygen present.
Only a slight suspended solids gradient is seen through the lagoons indicating that
on this date the influent suspended solids (period average 150 mg/l) were rapidly
settled.
Sludge Storage and Decomposition
In order to evaluate the facultative lagoons as a means of solids storage and
decomposition a solids material balance was made around the system after operation
had ceased. To determine the solids accumulated, samples of the lagoon contents
were collected by lowering a piece of glass tubing to the bottom of the lagoon .
The top was then stoppered and the tubing withdrawn. The bottom of the tube was
stoppered before lifting above the surface of the water. The tubing containing the
73
-------
TABLE 21
FACULTATIVE LAGOON SUMMARY
Nunier 1 Effluent Number 2 Effluent
Dot* pHTamp. CODj CODp TSS VSSBODy BODf Alt pHCODjCODp TSSVSSAMt pHCODT CODp TSSVSS BODT BODp AUT BODT tODf
11-2 to
11-22-70 7.6 17 444 306 138 87 95 51 448 7.5 371 263 79 60 479 7.7 322 215 61 38 36 29 62
11-23(0
12-17-70 7.7 19 383 266 138 95 74 69 344 7.5 354 250 94 67 355 7.6 327 243 89 55 70 338 5
12-18-70 fo
1-3-71 7.8 19 445 306 222 155 72 528 7.8 382 290 121 89 498 7.9 330 265 103 69 45 489 38
1-4to
1-11-71 8.4 10 557 444 184 121 145 90 578 8.0 437 368 141 103 548 8.0 403 335 123 92 67 559 54
1-12 to
2-4-71 7.8 17 428 230 220 169 94 64 386 7.8 307 255 102 70 404 7.8 302 236 s85 58 46 442 51
2-5to
2-15-71 7.7 13 374 181 198 161 59 26 264 7.5 248 172 90 72 338 7.6 225 180 75 55 31 22 354 48 15
2-16 to
3-9-71 7.2 17 343 234 174 134 53 2B 210 7.1 280 223 70 55 209 7.3 242 195 55 39 32 20 217 40 28
3-10 to
4-14-71 7.6 19 430 267 156 134 85 33 414 7.5 343 254 72 59 418 7.5 289 247 49 36 48 24 410 43 27
4-15 to
5-27-71 8.0 23 522 246 283 246 104 30 583 7.8 409 268 148 132 609 7.9 354 259 117 102 55 25 628 47 16
5-28 to
6-30-71 7.2 26 488 275 254 212 95 37 609 7.7 361 303 102 83 724 7.8 320 264 86 70 49 28 753 48 24
* Aerated <(ob!liza(ion affluent wai find to No. 1 Lagoon, which in (urn hd into No. 2 Lagoon.
Units are at expressed in Table 7.
-------
FIGURE 23
RELATIONSHIP OF LAGOON FEED AND EFFLUENT SOLIDS LEVELS
vj
en
Total suspended solids
Volatile suspended solids
120 160 200
Influent Suspended Solids, mg/l
-------
TABU 22
PROFILES OF FACULTATIVE LAGOONS I AND II
North Section I
South Section I
South Section II
North Section II
12 Noon 3-9-71
pH
ORP, mv
Temp., ",C
DO, ma/I
COD, ma/'
TSS/VSS, mo/I
Sulfide, mfl/l
S04, ma/I
Surface
7.0
-160
15
2.4
270
72/56
5
600
3 Ft
6.9
-260
15
0.3
270
70/56
6
600
6 Ft
6.9
-260
14
0.2
280
66/50
10
590
Sludge
6.6
-300
13
0.2
255
78/63
19
560
Surface
7.0
-190
15
0.6
275
70/56
5
595
3 Ft
7.0
-230
15
0.3
270
76/58
9
615
6 Ft
6.4
-320
13
0.2
375
76/60
8
615
Sludge
6.7
-340
14
0.2
265
83/72
17
610
Surface
7.3
-120
16
3.8
225
68/52
6
630
3 Ft
7.2
-220
17
1.8
230
64/48
8
655
6 Ft
7.2
-230
12
1.6
230
64/46
9
630
Sludge
6.8
-300
13
2.4
190
78/62
80
245
Surface
7.2
-200
16
0.6
230
64/48
19
600
3 Ft
7.2
-260
15
0.3
225
60/46
15
610
6 Ft
7.1
-270
18
0.4
235
68/52
18
590
Sludge
6.9
290
13
0.3
205
74/62
45
430
Notes: Flow it from North I
-South I-
-South II
-North II
-------
sample was lowered into a dry ice-acetone mixture, frozen, and cut into 6-inch
sections. The sections were thawed completely prior to performing the analyses
indicated in Table 23.
Based on the solids monitoring data for the influent and effluent (Table 21), 2347
pounds of total suspended solids and 1938 pounds of volatile suspended solids were
removed during the 231-day operational period. Solids remaining in the lagoon
system were composed of 1030 pounds total suspended solids and 585 pounds
volatile suspended solids. A material balance proved that degradation of total and
volatile suspended solids amounted to 50 and 70 percent, respectively. A change
in volatility from 82 percent to 56 percent was observed with the decomposition.
The maximum final sludge composition observed was 3.7 percent total suspended
solids.
Useful life of the lagoon system can be estimated as follows. If a 4-foot allowable
sludge depth, a 4 percent final sludge concentration, a 240 mg/l TSS influent, and
removal and degradation as existed in the demonstration system are assumed, then
the two 2-day lagoons would have a useful life of 4.6 years before cleaning.
77
-------
TABLE 23
FACULTATIVE LAGOON SLUDGE PROFILE
Organic
Soluble
COD, TSS, VSS,
mg/l mg/l mg/l
Basin #1 Influent Area 7 s
Bottom 6" Section 1,470 22,900 13,800 72 7.5
2nd 6" Section from Bottom 1,220 21,800 13,700 96 7.3
3rd 6"Section 1,080 13,700 8,140 192 7.4
1" Above Sludge Level 430 140 60 84 7.7
Basin *1 Effluent Area
Bottom 6" Section 930 25,510 17,000 132 7.2
2nd 6"Section from Bottom 880 19,600 11,400 144 7.3
1'Above Sludge Level 210 72 52 60 8.0
Basin *2 Influent Area
Bottom 6 "Section 380 6,640 3,510 72 7.7
1" Above Sludge Level 255 68 44 72 8.1
Basin #2 Effluent Area
Bottom 6" Section 795 37,400 16,000 192 7.5
1'Above Sludge Level 245 72 44 48 8.0
78
-------
SECTION VIII
OVERALL SYSTEM PERFORMANCE AND SPECIAL STUDIES
Overall system performance in terms of BOD and COD removal is presented in
Table 24, Except during the period of the low oxygen study in the aerated
stabilization system, the series system consistently provided a total BOD removal of
greater than 90 percent and a soluble BOD removal of 95 percent or greater. A
total COD removal of 75 to 81 percent was observed during this period. Twelve
analyses of the aerated stabilization and facultative lagoon effluents by gas
chromatography indicated that none of the identifiable components entering the
treatment system were present in identifiable quantity in the effluent from either of
these processes. The treatment system operated on-line during the entire study
except for equipment problems. As mentioned under the anaerobic lagoon section,
the ability of the lagoons to absorb both organic and pH shocks and to provide a
long term BOD removal of greater than 90 percent served to demonstrate system
reliability.
In order to estimate nutrient requirements and to determine the fate of nutrients
in the anaerobic-aerobic system, analyses were selected or developed for testing
samples collected at various points in the system, It was necessary to develop
ammonia and phosphate methods applicable to anaerobic systems and to systems
containing amine wastes. The methods used are included as a part of Appendix II,
while data obtained are listed in Table 25. Nitrate data indicate that little nitrate
ion enters the treatment system and that no nitrification occurs in the aerated
stabilization process.
Ammonia and phosphorous data are inconclusive, apparently indicating only the
variable influent content in the wastes. Little definable uptake through the
biological system was noted.
Long term (20-day) BOD concentrations also were determined in special studies on
the demonstration-scale facility. Data are presented in Table 26 which includes
a ratio of 5-day to 20-day BOD. A comparison of 20-day BOD, 5-day BOD, and
COD removals are listed in Table 27.
The BOD5/BOD2Q ratio could be considered indicative of the relative ease of
degradation of a waste, assuming a seed equally acclimated to all compounds, An
easily or a rapidly degraded waste would have a ratio near one, while a slowly
degraded waste should have a ratio considerably less than one. In passing through
a treatment process a heterogeneous waste would be expected to have a decreasing
ratio if the easily degraded compounds were preferentially removed. If all
79
-------
oo
o
TABLE 24
OVERALL SYSTEM PERFORMANCE
Influent, mg/l
Date
1 1-3-70
to 2-7-71
2-8-71 to 3- 10-71
3-11-71
4-15-71
to 4- 14-71
to 6-30-71
BOD
478
417
550
881
COD
986
967
1138
1786
Effluent
BOD
52
32/20
48/24
52/26
/ mg/l
COD
328
237
289
339
Removal, %
BODT
89
92
91
94
BODp
95
96
97
COD
67
75
75
81
Notes
Includes period of low oxygen
study in aerated stabilization
basin
Increased influent concentratic
period
Note - Units are as expressed in Table 7.
-------
TABLE 25
NUTRIENT ANALYSES
Nutrient (o)
System (b)
Influent
Anaerobic- Lagoon
Effluent
0.2
45.8
56.6
January 21, 1971
NO3
Ortho-PO4 (c)
Total Hydrolyzabie
Phosphate (TH-PO4)
March 17-19, 1971
NO3
NHo (d)
Ortho-PO4
TH-PO4
March 20-22, 1971
N03
NH3
Ortho-PO4
TH-PO4
April 24-26, 1971
NH3
April 27-29, 1971
NH3
June 14, 1971
N03
NH3
Ortno-PO4
(a) Concentration of nitrate ions and ammonia are mg/l or N, phosphorous forms are
as phosphate
(b) 3-day composite sample
(c) 40 mg/l K^PCty added as nutrient
(d) 45 mg/l NHg added as nutrient
0.3
247.0
41.0
0.3
62.0
25.0
60.0
254.0
75.0
0.3
39.0
44.0
0.1
100.0
20.0
72.0
0.1
65.0
32.0
107.0
212.0
171.0
0.3
34.0
69.0
0.3
74.0
38.0
0.2
64.0
22.0
65.0
167.0
131.0
0.3
25.0
67.0
~
0.2
49.0
36.0
53.0
94.0
51.0
0.3
26.0
44.7
0.2
68.0
42.0
0.2
22.0
36.0
55.0
144.0
106.0
0.2
22.0
77.0
81
-------
00
TABLE 26
LONG TERM BOD DATA
20-day BOD, mg/l
Anaerobic Lagoon
Aerated
. Date
9/18/70
9/19/70
9/20/70
9/21/70
9/22/70
9/23/70
9/24/70
9/25/70
9/26/70
9/27/70
9/23/70
9/29/70
9/30/70
10/1/70
10/2/70
10/3/70
10/4/70
10/5/70
10/6/70
10/7/70
10/8/70
10/9/70
10/10/70
10/11/70
10/12/70
10/13/70
10/14/70
Influent
_.
~
698 (0.96) (a)
460 (0.98)
~
726 (0.87)
626 (0.84)
598 (0.97)
375(1.17)
--
518 (0.97)
No. 1 Effluent
__
104(1.50)
133 (0 87)
135 (1.07)
178 (0.94)
158 (0.77)
~
140(1.31)
--
~
--
144 (0.97)
~
No. 2 Effluent
135 (1.11)
153 (0.86)
1 15 (0.99)
206 (0.95)
202 (0.97)
144 (0.96)
158 (1.01)
Stabilization Effluent
56 (0.45)
~
28 (0.71)
69 (0.74)
48 (0.79)
56 (0.79)
52 (0.65)
34 (0.74)
58 (0.79)
72(1.19)
106 (0.60)
74 (0.93)
68 (0.93)
52 (0.44)
44 (0.59)
35 (0.51)
34 (0.47)
52 (0.81)
58 (0.98)
54 (0.67)
32 (0.88)
42 (0.71)
44 (0.61)
27 (0.96)
29 (0.79)
Focuitattv*
Lagoon Effluent
65
(continued)
-------
TABLE 26 (continued)
oo
CO
Date
3/19/71
3/20/71
3/21/71
3/22/71
3/23/71
3/24/71
3/25/71
5/20/71
5/21/71
5/22/71
5/23/71
5/24/71
5/25/71
5/26/71
5/27/71
Anaerobic Lagoon
Influent
1050 (0.40)
1045 (0.35)
1120 (0.72)
830(0.67)
1060 (0.72)
No. 1 Effluent
330 (0.55)
420 (0,59)
674 (0.55)
569 (0.65)
620 (0.64)
No. 2 Effluent
344 (0.51)
551 (0.34)
558 (0.62)
488 (0.63)
558 (0.60)
Aerated
Stabilization Effluent
(0.60) 126/46 (0.33) (b)
(0.48) 126/54(0.48)
(0.43) 188/62 (0.29)
(0.48) 150/56 (0.38)
(0.43) 126/61 (0.26)
_ . .
(0.41)214/72 (0.60)
(0.39)222/68 (0.54)
(0.43) 164/88 (0.45)
(0.37) 138/41 (0.61)
(0.31) 153/29 (0.79)
(0.40) 158/32 (0.59)
(0.54) 138/34 (0.76)
(0.47) 174/41 (0.73)
Facultative
Lagoon Effluent
133
58 (0.62)
(0.40) 89/57 (0.35)
(0.38) 134/54 (0.70)
(0.26) 144/50 (0.52)
(0.42) 124/44 (0.50)
(a) Number in parenthesis is ratio of
(b) Total BOD/filtered BOD.
-------
TABLE 27
COMPARISON OF LONG AND SHORT TERM BOO REMOVALS
Anaerobic Lagoon Removal,
8OD5 BOO2Q
Due
9/18 to 10/I5AO*
3/19 to 3/25/71*
5/10 to S/O/n*
No. 1
74
48
44
No. 2
67
58
49
No. 1
75
64
38
No. 2
72
57
47
COO
No. 1
53
36
42
No. 2
53
41
48
Aerated Stabtlln
Removal, %
BODj
70
70
84
BOD20
64
62
73
iHon
Overall Removal, %
COO B005 BOOjo COD Feed
50 0.97
41 91 91 75 0.3B
54 94 87 81 0.70
No. 1
Anaerobic
Lagoon
1.06
0.57
0.61
No. 2
Anaerobic
Lagoon
0.96
0.42
0.62
Aerated
Stabilization
Effluent
0.75
0.48
0.42
Facultative
Effluent Wale Feed
Dilute woite
0.47 Preview ly treated
anaerablcallx
0.35 Additional cane.
feed
Note - Removal data far BOOj and COO en band on lono-fwm averagei containing fheie doto.
-------
compounds were removed equally a slightly decreased ratio might be expected due
to somewhat less degradable biological intermediates. An anaerobic process with
inefficient methane fermentation could conceivably provide an increased ratio with
the conversion of complex, slowly degradable organics to readily degradable
volatile acids.
Examination of the BOD /BOD2Q ratios with removals and waste feed data yields
an interesting comparison of the anaerobic and aerobic processes. During the first
period in which only a dilute waste was fed to the system the BOD5/BOD2Q ratio
increases slightly through the anaerobic step. A marked decrease in the ratio
(1.06 to 0.75) was observed in the aerobic step. The ratio greater than one reflects
some difficulties in the long-term BOD determination which subsequently were
overcome as discussed in Appendix II. Note that during this period 6065 and
BOD2Q removals were roughly equivalent and considerable greater than COD
removals.
During the second experimental period the effluent from a long-retention anaerobic
lagoon was added to the feed. Again an increase in the BOD5/BOD2Q ratio is
observed through the anaerobic process with a decrease in the aerobic step
(0.57 to 0.48 - the aerobic unit received the effluent from the No. 1 lagoon).
The feed ratio was much lower in this case reflecting the presence of the well
degraded waste in the feed. In this case BOD2Q removals were greater or equal
to BOD5 removals in the anaerobic process. Less BOD2Q than BOD5 removal
occurred in the aerobic process.
In the last experimental period dilute waste was supplemented with a concentrated
waste. During this period the anaerobic system ratio declined less than did the
aerobic system indicating less of a change in degradability with significant removal
of organics, During the last period, anaerobic system BOD^, BOD2Q ar|d COD
removals all are roughly equivalent while aerobic 8OD5 removal is greater than
BOD2Q removal reflecting the lower degradation of more slowly reacting materials,
The long-term BOD data suggest that while the higher rate aerobic system may act
to remove readily degradable materials preferentially, the anaerobic system acts
on all degradable influent material with only a small change in waste degradability
with organic removal. The similar BODc and BOD2Q removals observed in the
anaerobic system compared to the greater BOD5 than BOD2Q removal in the
following aerobic treatment support the hypothesis, Additional experimental work
would be necessary for a definite confirmation of this suggested basic difference
in the two process types.
85
-------
SECTION IX
LAGOON PROCESS ECONOMICS
Design criteria developed from the demonstration study and supplemented by
additional plant and small-scale pilot data for anaerobic lagoons have been used
to make an economic evaluation of the anaerobic-aerobic system.
Investment and operating cost estimates have been prepared for three plant sizes.
An investigation of the variation of construction cost with waste strength also was
made for one plant size. Finally, a comparative cost estimate of the anaerobic-
aerobic system and a completely mixed activated sludge system was made,
The Anaerobic-Aerobic System
The anaerobic-aerobic system for which cost studies were made includes pH adjust-
ment, primary clarification, anaerobic lagoons, aerated stabilization, and
facultative (solids removal) ponds.
The design basis for these studies and expected performance of each unit operation
during summer and winter conditions is shown in Figure 24. The design detention
time for each step at an influent BOD5 level of 800 mg/l is listed. For the
particular wastes tested a COD concentration of approximately 1600 mg/l would be
expected. For some other petrochemical waste the degradable fraction of organics
present could be expected to vary significantly from this observed 2:1 ratio. The
major difference between warm and cold weather performance is due to the reduced
performance of the anaerobic lagoon as temperature decreases. Overall BOD5
removals of 95 and 90 percent are expected in summer and winter, respectively, at
design conditions. Since the BODjCOD ratio could be expected to vary with
different petrochemical wastes, the COD removal efficiency is not a particularly
reproducible parameter between wastes. However, a removal of approximately
1.7 Ib COD/lb BOD/j removed was noted in the pilot studies. This parameter should
be reasonably consistent between wastes.
A solids level of 200 mg/l is expected in the aerated stabilization system, Settling
provided in the facultative ponds will produce an effluent with 75 mg/l of suspended
solids. Some degradation of settled solids is expected. No long-term solids
degradation data are available, but short-term data show that approximately fifty
percent of the suspended solids will be degraded in one year. Cost estimates are
based on periodic dewatering and incineration of waste sludges.
A summary of the major assumptions used in preparation of the cost estimates is pro-
vided in Table 28. Table 29 contains a tabulation of the major structural and mechan-
ical features for the 0.5, 10.0, and 25.0 million gallon per day plants chosen for
study.
87
-------
SUMMER
FIGURE 24
TYPICAL REMOVAL EFFICIEHCIES FOR ANAEROBIC-AEROBIC SYSTEMS
BASIS - 100 LB. BOD- TO PRIMARY CLARIFIER
800 ne/1 WASTE STRENGTH
100
PRIMARY
12(D
88
ANAEROBIC
70
26 A
AERATED
STABILIZATION
79
5
FACULTATIVE
POND
20
n ji
OVERALL REMOVAL 95.6*
oo
oo
WINTER
100
PRIMARY
12
88
ANAEROBIC
*7
1*6.6
AERATED
STABILIZATION
72
13-1
FACULTATIVE
POND
20
10. k
OVERALL REMOVAL 89.6ft
DESIGN DETECTION TIMES
ANAEROBIC - 15 DAYS
AERATED STABILIZATION - 3 DAYS
FACULTATIVE POIDS - 8 DAYS
ROTES
(1) Values in unit box represent percent BO05 removal across that operation or process in the pilot operations
(2) A removal of 1.7 Ib COD/lb BOD5 removed was noted in pilot studies
-------
TABLE 28
MAJOR ASSUMPTIONS OF THE STUDY
1. Earthwork slopes are two horizontal units for each vertical
unit,
2. Piling is required under all major structures,
3. A Gulf Coast location is assumed.
4. All earthen basins are lined with four inches of concrete from
the top of the slope to two feet below the water surface unless
otherwise noted.
5. Basin interconnect piping is low-head corrugated metal drain-
age pipe with protective coating.
6. All costs adjusted to 1971 dollars.
89
-------
TABLE 29
ANAEROBIC-AERATED STABILIZATION SYSTEM
SUMMARY OF MAJOR EQUIPMENT
Plant Size (mgd)
Neutralization
No. of Compartments
Materials of Construction
Dimensions, ft
Plan
Depth
Horsepower
Piling
Control Loops
Primary Clarification
No. of Units
Dimensions, ft
Diameter
SWD
Freeboard
Piling
Anaerobic Ponds
No. of Units
Dimensions, ft
Length (1)
Width
Depth
Aerobic Basin
No. of Units
Dimensions, ft
Length (1)
Width
Depth
Aerators (mechanical, floating)
Number
Horsepower
0.5
2
Concrete
6.0x7.5
8
10
Yes
2
2
18
9
3
Yes
2
180
255
15
2
187
72
10
ia}
'9/
6
25
(continued)
90
10.0
2
Concrete
20x20
12
60
Yes
2
2
80
9
3
Yes
2
1060
676
15
2
676
325
10
28
75
25.0
4
Concrete
22x22
12
80
Yes
4
4
90
9
3
Yes
4
1155
780
15
4
770
350
10
50
100
-------
TABLE 29 (continued)
Plant Sjze (mad)
0.5 10.0 25.0
Facultative Ponds
No. of Units 444
Dimensions, ft
Length (1) 162 677 762
Width 162 677 1475
Depth 666
(1) Length and width dimensions are measured at water
surface.
91
-------
The Activated Sludge System
Design parameters for the activated sludge system used in this study were developed
from pilot scale work conducted on wastewater similar to that used for the anaerobic-
aerobic study (3). The treatment system consists of pH adjustment, primary clarifi-
cation, equalization, activated sludge and final clarification. Sludge disposal
costs were estimated by adjusting published unit cost data for investment and
operating costs to incorporate bench-scaledewatering data.
The principal design criteria for the biological reactor and final clarification
tanks are tabulated below:
Detention Time 17 hours
Food to Biomass Ratio 0.45/day
MLSS 2500 mg/l
BOD5 Removal 88%
Clarifier Overflow Rate 600 gal/day-ft
Cost estimates for the activated sludge system include two features which are not
included in the anaerobic-aerobic system. A concrete lining is included in the
aeration basins for erosion protection. Fixed mounted surface entrainment aerators
are included to facilitate maintenance of closely spaced equipment. No estimate
of COD removal efficiency was made for the activated sludge system.
Cost Estimates
Anaerobic-Aerated Stabilization
Construction cost estimates were prepared for plants with daily flow of 0.5, 10.0,
and 25.0 million gallons. A waste strength of 800 mg/l BOD5 was selected for the
base case estimate. This study yielded a cost of $168, $33, $28 per pound of BOD
per day applied with increasing plant size. A construction cost summary is presented
in Table 30. The respective operating cost for each plant is shown in Table 31.
Operating costs for the plants are $0.073, $0.022, $0.018 per pound BOD applied
as size increased.
A further extension of the study was made by holding the waste flow constant to a
10.0MM gallon per day plant and increasing waste strength to 2000 mg/l. The only
significant increase in construction cost with increasing waste strength is for aeration
capacity. Figure 25 presents the variation in total and unit construction cost.
Operating cost increase with waste strength is related to increases in reagent dosage
and aeration horsepower. A significant decrease in cost per pound of BODc applied
can be observed in Figure 26.
92
-------
TABLE 30
CONSTRUCTION COST SUMMARY
ANAEROBIC-AERATED STABILIZATION SYSTEM
Plant Size (mgd)
System Component
Neutralization
Structural
Mixing
Reagent Storage
pH Control
Clarification
Structural
Mechanical Equipment
Anaerobic Ponds
Earthwork
Concrete Liner
Aerobic Basin
Earthwork
Concrete Liner
Aeration Equipment
Electrical Support
Facultative Ponds
Earthwork
Concrete Liner
Piping
Instrumentation
Building and Lab Equipment
Site Preparation
Land at $1 ,000/acre
Sub- Total
Construction Contingency
Construction Cost
Cost/Lb, BOD Applied
Cost/1000 Gal.
0.5
$ 6,800
3,000
30,400
12,000
20,700
20,700
70,800
1,900
63,800
10,000
45,000
22,800
36,500
15,400
38,700
30,000
34,000
22,000
9,000
$506,000
51,500
$560,000
$ 168
$ 1,120
10.0
$22,000
9,300
30,400
12,000
123,600
59,000
326,500
39,300
209,500
32,800
448,000
85,500
135,500
59,100
167,400
56,000
51,000
49,100
100,000
$2,016,000
209,000
$2,225,000
$ 33
$ 222
25,0
$51,000
15,500
60,800
24,000
279,300
146,000
516,500
104,300
368,300
77,100
900,000
194,000
323,000
239,000
412,600
115,000
70,000
93,600
230,000
$4,220,000
430,000
$4,650,000
$ 28
$ 186
93
-------
TABLE 31
ESTIMATED OPERATING COST
ANAEROBIC-AERATED STABILIZATION SYSTEM
Plant Size. MM gal/day
0.5 10.0 25.0
Operating Labor & Supervision
Technical Supervision $ 5,800 $17,500 $17,500
Day-Shift Supervisor 6,200 12,500 12,500
Operators 36,400 72,800 72,800
Laboratory Analysis 5,200 18,000 20,000
Mechanic-Instrument Man 5,200 10,400 15,600
Reagents
NH3-lLb N/20 Lb. BOD 500 10,000 25,000
H3PO4-lLb P/100 Lb, BOD 200 23,800 59,50.0
H2SO4- 3000 Lb- 93% Acid/MM Gal 7,800 150,000 375,000
Power (1)
Aeration Horsepower x 1.15 11,400 157,000 372,000
Maintenance
2.0 Percent of Construction Cost 10,000 44,000 80,000
Operating Supplies 300 2,000 4,100
Annual Operating Cost $90,000 $518,000 $1,054,000
Sludge Disposal (2) 20,000 25,000 70,000
Amortize Investment - 20 yrs at 6% 49,000 194,000 405,000
Total Annual Cost $159,000 $737,000 $1,529,000
Cost/1000 Gallons $0.87 $0.21 $0.17
Cost/Lb BOD Removed $0.14 $0.034 $0.028
Cost/Lb COD Removed $0.081 $0.020 $0.016
(1) Power at $0.01 per kw-hr
(2) Annual operating plus investment costs
94
-------
FIGURE 25
VARIATIONS IN COST WITH WASTE STRENGTH
3.0
Oi
o
-a
o
o
U
o
i_
in
C
O
U
2.75
2.5
2.25
2.0
Anaerobic-Aerobic System
10.0 mgd
35
20
15
1000
1500
Waste Strength, mg/l BOD5
2000
o.
a.
o
10
Q
O
ca
O
U
c
a>
E
-*-
I/)
O
c
-------
FIGURE 26
VARIATION IN OPERATING COST WITH WASTE STRENGTH
.025
Anaerobic-Aerobic
10.0 mgd gal/day
o-
Sludge disposal costs not
included
1000
1500
2000
Waste Strength, mg/l
-------
Activated Sludge
Investment and operating cost data for a 10.0 million gallon per day plant are
presented in Tables 32 and 33. A total cost of $0.043 per pound of BOD removed
is forecast based on amortizing the capital investment at six percent interest over
a 20 year period.
System Comparison
The anaerobic-aerated stabilization system would be considered as a substitute
for a completely-mixed activated sludge system. A comparison of the two systems
is presented below:
SYSTEM COMPARISON
10.0 mgd
800 mg/l
Anaerobic/ Activated
Aerated Stabilization Sludge
Land Required (acres) 100 10
Effluent BOD5 (mg/l)
Warm 35 84
Cold 85 84
Effluent Suspended Solids (mg/l) 75 100
Cost/lb BOD5 Removal $0.034 $0.043
The anaerobic-aerated stabilization system will produce an effluent at least as good
as the activated sludge plant. A significant reduction in unit removal cost can be
expected. High land requirements and reduced efficiency at low temperature are
negative factors to be weighed.
Cost comparisons are based on total annual cost for each system, Conslruction cost
estimates for each system are based on actual layout and quantity estimates for all
components except sludge disposal. This construction cost estimate was reduced to
an annual cost to amortize the investment. The second element of annual cost was
estimated operating cost. The final element of total cost is a unit cost for sludge
disposal derived from the literature. This cost reflects both investment and operating
allocations. The development of the unit cost figures is shown in Table 33.
97
-------
TABLE 32
CONSTRUCTION COST SUMMARY
ACTIVATED SLUDGE SYSTEM
10.0 MM gal/day
800 mg/l
Neutralization Construction Cost
Structural $ 22,000
Mixing 9,300
Reagent Storage 30,400
pH Control 12,000
Primary Clarification
Structural 123,600
Mechanical Equipment 59,000
Equalization
Structural 78,100
Concrete Liner 17,400
Mixing 20,000
Aerobic Basin
Earthwork and Roadway 25,300
Concrete Liner 90,000
Aeration Equipment 504,000
Aeration Equipment Support 280,000
Electrical Support 67,000
Final Clarification
Structural 214,900
Mechanical Equipment 112,000
Piping 113,700
Instrumentation 50,000
Building & Lab Equipment 56,000
Site Preparation 28,300
Land at $1,000/acre 10,000
Sub-Total 1,923,000
Construction Contingency 192,000
Construction Cost $2,115,000
98
-------
TABLE 33
COST COMPARISON
10.0 MM GAL/DAY SYSTEMS
800 mg/l
Operating Labor and Supervision
Technical Supervision
Day-Shift Supervisor
Operators
Laboratory Analysis
Mechanic- Instrument
Reagents
NH3 - 1 Lb. N/20 Lb. BOD
H3PO4- 1 Lb. P/100 Lb. BOD
H2SO4 at 3000 Lb of 93% Acid/MM Gal
Power
Aeration Horsepower x 1.15
Maintenance
2.0% of Construction Cost
Operating Supplies
Annual Operating Cost
Sludge Disposal (1)
Amortize Investment - 20 yrs. at 6%
Total Annual Cost
Cost/Lb. BODR
Activated
SI udge
$ 17,500
12,500
72,800
18,000
10,400
13,300
49,000
150,000
210,000
42,000
2,000
598,000
153,000
184,500
935,000
$0.043
Anaerobic-
Aerated
Stabilization
$ 17,500
12,500
72,800
18,000
10,400
10,000
23,800
150,000
157,000
44,000
2,000
518,000
25,000
194,000
737,000
$0.034
(1) Sludge data unit costs include investment and operating
cost and are based on A Study of Sludge Handling and
Disposal by R. S. Burd, Publication No. WP-20-4,
Federal Water Pollution Control Administration,
May 1968.
99
-------
SECTION X
ALTERNATIVES. STUDIED
The alternative processes of anaerobic contact digestion and anaerobic trickling
filters were studied on a bench scale with synthetic wastes at the Union Carbide
Technical Center, South Charleston, West Virginia and on a semi-pilot scale at
Union Carbide's Texas City, Texas Plant using actual wastes,
Description of Wastes Treated
The synthetic waste treated in the bench-scale units is described in Table 34. The
units were started from domestic digesting sludge on a readily degradable mixture
of diluted acetic acid, ethano! and ethylene glycol. After active cultures were
developed the simulated chemical waste which contained eleven chemicals at equal
theoretical oxygen demand was used. Trace elements were added as were ammonia
and phosphate compounds for nutrient values in both feeds. Two strengths of
simulated waste were used, one of about 20,000 mg COD/I (25,000 mg theoretical
oxygen demand/I) and another of 2,000 mg COD/I (2500 mg TOD/I). The dilute
waste was prepared by adding one part of the concentrated waste to nine parts tap
water.
Petrochemical wastes were treated in semi-pilot scale studies at two concentration
levels. The actual petrochemical effluent streams from the Texas City Plant consisted
of one stream having an average COD of qbout 150Q mg/l, the other about 15,000
rng/1, The streams were,bjfnq'fe| with tap wafer to provide an in-between composition
feed for the filters. Sulfates In the feed ranged in concentration from less than
200 to more than 1500 mg/l. Specific organic chemicdls detected in the feed are
listed in Table 35.
Contact Digestion
Bench-scale contact digestion experimentation was performed in four completely
mixed 5-gallon carboys illustrated schematically in Figure 2. Tube and packed
bed type clarifiers were used for solids separation in the continuously fed systems.
Pilot scale studies were performed in a 5600-gallon, heated, hydraulically mixed
reactor equipped with an internal, tube type clarifier (Figure 27).
The bench-scale units were operated to determine feasible conditions for experi-
mentation in the pilot scale facility and to evaluate two types of solids separation
(tube clarifier and packed bed) and the effect of colloidal asbestos on solids
separation and digester performance.
101
-------
TABLE 34
ANAEROBIC TREATMENT OF SYNTHETIC ORGANIC WASTES
MIXED CHEMICALS - DIGESTER FEED
Date First Used 4-29-69
Theoretical Oxygen Demand, mg/l 25,000
Measured COD, mg/l (1) 20,000
Measured BOD5 (1) 19,600
Substrate
AceTic Acid 2124
Benzoic Acid 1165
Propionic Acid 1505
Acetaldehyde 1248
Phenol 955
Butanol 878
Ethanol 1093
Vinyl Acetate 1361
Butyl Acetate 1033
Monoethanolamine 914
Diethylene Glycol 1505
Buffer-Nutrient
(NH4)2CO3-H2O 4292
NaH2PO4-H2O 542
KH2P04 542
Trace Elements
FeCI3 180
MnSO4-H2O 3.08
CoCI2-6H2O 4.04
MoO3 1.53
ZnS04-H2O 5.32
Note: Concentrated mixtures were diluted with tap water as required,
(1) Mean of several analyses of diluted feeds recalculated to
original strength.
(2) Provided ratio COD/N/P ^ 100/5/1
102
-------
TABLE 35
DETECTED CONSTITUENTS OF WASTE USED AS FEED
IN SEMI-PILOT SCALE STUDIES
Aceta Idehyde
Acetic acid
Acetone
Ethylenediamine polymers
Benzene
Isobutanol
n-Butanol
Bis(2-chloroethyl) ether
Ethanol
Ethylene dichloride
Ethylene glycol
Isobutyra Idehyde
n-Butyra Idehyde
Hexanol
Methanol
Isopentanol
n-Pentanol
Isopropanol
n-Propanol
Propiona Idehyde
Methyl ethyl ketone
Waste tested at two dilutions: 1,500 and 15,000 mg
COD/I iter
NH.OH and H,PO4 added as nutrients; r^SO, and
NaOH added to adjust pH
103
-------
FIGURE 27
SEMI-PILOT CONTACT DIGESTER
Hydraulic
Mixing Pump
Feed Pumped
from 3000-gal.
mixed tank
Effluent
Tube-Type
Clarifier
8ft.
9ft.
Diameters
12.5ft.-
104
-------
The tube type of gravity clarifier separation system, illustrated in Figures 2 and 27,
exploits the theoretical advantages of low hydraulic flow per unit surface area of
clarifier (17). The tubes are inclined so as to be self-cleaning; the solids fall back
into the reactor or into a storage facility for recycle. In the laboratory packed bed
system, also alluded to in Figure 2, the solids are filtered from the effluent and
retained in the bed of gravel or glass beads. Periodic backflushing returns the solids
to the reactor.
The bench scale units operating on the dilute synthetic waste feed, described in
Table 34, gave satisfactory results of up to 80% chemical oxygen demand (COD)
reduction at hydraulic retention times (HRT) exceeding approximately 5 days
(Figure 28), while units treating the concentrated wastes experienced between 10
and 50% COD removal efficiency at 7 to 10 day HRT. At detention times of less
than 4 days the performance in some units treating dilute waste deteriorated indica-
ting either insufficient reaction time or organism washout.
The solids retention time (SRT) in the short HRT experiments decreased somewhat due
to less efficient solids capture at the increased flow and was in some cases relatively
near the minimum generation time of methane bacteria. Also, although the SRT
decreased both in the units receiving colloidal asbestos and those not receiving
asbestos, the organic removal efficiency remained approximately steady in those
units receiving asbestos. It is hypothesized that the asbestos provides growth sites
for the methane bacteria and may serve to selectively concentrate these or other
surface cultures as well as aid in overall organism separation. The range of SRT
covered was 5 to 130 days while loadings were 10 to 190 Ib. COD/1,000 cu ft/day.
The effects of asbestos addition in dilute waste treatment are further shown in
Figure 29. The organic loading was increased by feeding a more concentrated waste
while holding the HRT above 5 days. The resulting removal per unit volume increases
but at a lesser rate. A line with an intercept of zero and a slope of one would
indicate constant removal efficiency. The steeper slope with the units receiving
asbestos indicates increased efficiency, at least at loading of 15 Ib. COD/1,000
cu.ft./day or greater. The asbestos served to increase the digester suspended
solids level and to avert solids separation difficulties.
The purpose of the bench scale experimentation was to determine feasible operational
conditions and preliminary design information. As a result, the units were not
necessarily allowed to come to steady state, but conditions were changed after an
adequate removal was established. The bench scale units did point out the
effectiveness of the less costly tube type of clarifier and the advantages of colloidal
asbestos in the feed.
105
-------
FIGURE 28
EFFECT OF RETENTION TIME ON COD REMOVAL
IN LABORATORY CONTACT DIGESTERS
4 6
Retention time, days
106
-------
FIGURE 29
REMOVAL VS LOADING FOR CONTACT DIGESTER
BENCH SCALE UNITS
24
1 18
u
o
8
O
u
JO
"5
12
Dilute Synthetic
Waste Only
12 18 24
Loading, Ib. COD/1000 cu. ft ./day
-------
Pilot scale experiments were performed on concentrated wastewater only, as full
scale contact reactor facilities were visualized as economically unfeasible for a ^
large volume, dilute waste stream. Colloidal asbestos was added to the pilot unit
feed at a 25 mg/liter level to aid in solids separation.
The COD removals experienced for 6 and 10 day HRT were 21 and 34%, respectively,
as illustrated in Figure 30. These removals were not as substantial as desired but
were consistent with those experienced in the bench scale units treating concentrated
wastes at similar loadings. Figure 31 illustrates the relationship observed between
volumetric loading and removal efficiency for both bench and pilot scale units.
Suspended solids were maintained at a suitable level of 5,000 mg/liter in the
pilot digester through 85 to 95% solids capture efficiency in the tube clarifier,
One factor possibly limiting semi-pilot-scale performance was the high influent
sulfate level. The 500-to-800 mg/l level of sulfates was reduced to sulfides, with
50 to 100 mg/l sulfides remaining in the mixed liquor and the remainder lost as
hydrogen sulfide in the digester gas. The oxygen demand of contained sulfides was
included in the effluent COD measurements in all experimental results. The sulfide
levels found were marginal for inhibition of methane bacteria. Sulfides can be
tolerated at 50 to 100 mg/l, can be acclimated to up to 200 mg/l, and are
definitely toxic at above 200 mg/l (18). Means of combating sulfide toxicity would
be precipitating with heavy metals or mixing the unit by gas recycle to allow scrub-
of additional sulfide from the liquid.
The high volatile acid level also could be a cause of semi-pilot-scale digester
performance limitation. Feed volatile acids ranged from 3000 to 4000 mg/l as acetic
and increased with residence in the reactor. Although Andrews (19) has indicated
that dissociated volatile acids are inhibitory at approximately 2000 mg/l, others (20)
have indicated inhibition to be dependent on the associated cation. Batch studies
of the digester mixed liquor yielded good methane production showing a methano-
genic culture was present, but possibly inhibited in treating the actual concentrated
waste stream. In contrast, volatile acids in the dilute waste feed in bench scale
units which provided acceptable COD removal were approximately 400 mg/l as
acetic acid and dropped to less than 200 mg/l in the reactor indicating good
conversion of the produced acids.
Anaerobic Filters
The performance of anaerobic filters was evaluated both in 1.4 gal bench
units and in 35 gal pilot scale units (Figure 32). Laboratory units were packed with
1-in berl saddles yielding a 58% void volume, while 1-in diameter river gravel was
used in pilot studies (41% void volume). The laboratory unit was 3.5 in in diameter
and 25 in high, while these dimensions were approximately tripled in the pilot unit.
Annular ring baffles were installed to prevent short-circuiting along the sides.
108
-------
18000
16000
^o"
"o
c
o
o
O
O
U
12000
8000
FIGURE 30
SEMI-PILOT SCALE CONTACT DIGESTER PERFORMANCE
INFLUENT AND EFFLUENT COD
Period A - 10 Day Detention - Increasing Feed Strength
B - 10 Day Detention - Full Strength
C - 6 Day Detention - Full Strength
4000
10
20 30 40
Elapsed Time, days
50
60
-------
FIGURE 31
CONTACT DIGESTER, EFFICIENCY AT VARIOUS LOADINGS
O Synthetic wastewater
A Synthetic with asbestos additive
D Plant wastewater
D
Concentrated
60 90 120
Loading, Ib. COD/1000 cu. ft./day
180
-------
Thermistor
Vent
Seal Leg
x
Connections
Electrically
Traced Packed
Column
k
/ef Test Meter
Peristaltic
Feed Pump
Effluent
FIGURE 32
ANAEROBIC FILTERS
-------
Both dilute and concentrated simulated wastes were treated in laboratory scale units,
while a concentrated plant waste diluted with tap water was treated in the pilot
studies. Both types of experimental units were heated to 32° to 35°C
The anaerobic filters operated satisfactorily on dilute wastes over the loading range
tested, up to 130 Ib COD/1,000 cu ft/day based on total filter volume. For the
type of subsh-ate described in Table 34, removal efficiencies ranged from 60 to 80%
over a retention time of 0.5 to 2.0 days at 32°C. The average weekly data were
grouped around a 70% removal at 1.0 day HRT (Table 36).
The bench scale filter receiving concentrated wastes failed, probably due to the
introduction of a concentrated synthetic petrochemical feed to this unit started on an
alcohol and volatile acid feed. The waste loading per se to the concentrated unit
should not have been enough to cause failure unless rapid production of volatile acids
combined with the high level in the feed was inhibitory to the methanogenic culture
or a specific constituent was at an inhibitory level.
The pilot scale filters were started by seeding with an acclimated anaerobic sludge
which was actively producing methane. Three filters were started under identical
conditions, thought to be conservative, to achieve a high initial removal level.
However, satisfactory removals were never obtained over the 90 day run in spite of
attempts to optimize operating conditions. COD reductions at 34°C and a retention
time of 3 days tended to stabilize at 10 to 13% as shown in Figure 33.
Methane was produced during the course of pilot filter operation, indicating that
some methanogenic population was present. The methane could also have been
produced directly from simple substrates in the feed such as methanol and reduction
of carbon dioxide by hydrogen without conversion of produced or fed volatile acids.
Feed volatile acids ranged from 600 to 1,500 mg/liter as acetic. This level increased
approximately 30% through the units, indicating an active acid forming population
and an insufficient methane population to convert the produced acids. Volatile acid
levels found in the unit were below levels reported to be inhibitory,
Sulfates at 150 to 200 mg/l in the feed were reduced to sulfides with some escaping
as hydrogen sulfide in the produced gas. Effluent dissolved sulfides ranged from
50 to 100 mg/l. Sulfide toxicity again was only a marginal problem, but varying
sulfate feed levels or a dropoff in sparging gas production would cause toxicity
problems. Inhibition could have resulted from a specific chemical in the feed or one
formed in an intermediate breakdown step.
112
-------
TABLE 36
LABORATORY ANAEROBIC FILTER STUDIES ON DILUTE WASTE
Study Period, Average Retention Time, Average COD Removal,
weeks days %
1 - 8th 2.7
9 - 12th 7.5
13- 15th 1.9 76
16-18th 1.1 73
19 - 21st 0.92 69
22-24th 0.86 70
25 - 27th 0.69 64
113
-------
FIGURE 33
PERFORMANCE OF SEMI-PILOT SUBMERGED FILTERS
22 29 6 13 20 27
|*-Nov.*4« December, 1969
3 10 17 24 31
January, 1970 *(*-
7 14 21
February, 1970
28
-------
Specific Organic Analyses
The overall performance of the pilot scale contact digestion and anaerobic filter
units can be examined more closely if the specific organic compounds and removals
for each process are compared. Tables 37 and 38 contain a listing of chromato-
graphically identified compounds from the contact digester and filters while those
for the lagoons were listed previously in Tables 12 and 13. The analyses were made
on a number of composite or grab samples while the mean level for each compound
is the average for the number of times observed.
In both the contact digestion and anaerobic filter process a decrease in the concen-
tration of all applied organics except volatile acids was noted. An increase in the
concentration of metabolic intermediates such as acetic, propionic, butyric, and C
-------
TABLE 37
REMOVAL OF SPECIFIC COMPOUNDS IN CONTACT DIGESTION STUDIES
Feed (a)
Compound
Acetaldehyde
MethanOl
Ethanol
Acetone
Isopropanol
n-Propanol
Methyl ethyl
ketone
Acetic acid
Isopentanol
Ethylene glycol
n-Butyraldehyde
Hexanol
Pentanpl
Isobutyraldehyde
Propionic acid
Isobutanol
Butyric acid
Cg acid
n-Butanol
Propionaldehyde
Unknown
Benzene
Mean
44
155
74
100
62
269
50
788
331
306
91
139
88
102
0
241
0
0
210
50
0
50
Maxi-
mum
50
225
100
550
100
350
50
1900
640
500
'115
260
100
160
0
300
0
0
280
50
0
50
Mini-
mum
30
75
45
30
45
50
50
180
150
200
50
50
75
50
0
50
0
0
50
50
0
50
Number of
Occurrences
10
10
10
10
10
4
1
10
7
8
6
7
2
5
0
7
0
0
7
1
0
1
Mean
9
37
52
25
56
43
0
973
80
61
28
50
0
30
525
94
357
200
61
0
200
0
Maxi-
mum
10
80
80
50
100
45
0
1550
100
70
50
50
0
40
1200
120
850
200
100
0
370
0
Effluent
Mini-
mum
5
10
30
10
15
40
0
365
40
50
15
50
0
15
40
10
60
200
10
0
100
0
Number of
Occurrences
5
11
11
11
12
2
0
12
5
6
5
1
0
5
10
9
9
1
10
0
7
0
Conversion,
mg/l compound
mg/l total carbon
1.83
2.67
1.92
1.61
1.67
1.67
1.50
2.50
1.47
2.58
1.50
1.42
1.47
1.50
2.06
1.54
1.28
1.70
1.54
1.61
1.08
(a) Concentrations are as mg/l total carbon
(b) Average of 12 samples, composite and grab
(c) Detention time 6 to 10 days
Temperature 34 °C
Loading 60-160 Ib COD/1000 cu ft/day
-------
TABLE 38
REMOVAL OF SPECIFIC COMPOUNDS IN ANAEROBIC FILTER PILOT STUDIES (a)
Feedjb)
No. 1 Filter Effluent
No. 2 Filter Effluent
No. 3 Filter Effluent
Compound (c)
Acetaldehyde
Methonol
Ethanol
Acetone
Isoproponol
n-Ftopanol
Methyl ethyl
kerone
Acetic acid
n-Butanol
n-Pentanol
Ethylene glycol
Hexanol
Isopentanol
Propionie acid
Butyric acid
Isobutyraldehyde
rr-Butyroldehyde
Cjocid
Isabulanol
Unknown
Mean
39
59
49
38
52
35
15
531
25
35
168
76
263
0
0
88
58
0
82
150
Maxi-
mum
75
100
100
50
150
40
15
750
25
35
275
100
300
0
0
100
100
0
120
150
Mini-
mum
10
10
20
10
5
30
15
190
25
35
5
10
175
0
0
75
15
0
75
150
Number of
Occurrences Mean
9
9
9
9
9
2
2
9
1
1
9
7
6
0
0
2
2
0
3
1
9
19
7
29
34
5
10
746
20
0
125
50
100
160
144
5
15
110
5
130
Maxi-
mum
10
50
10
25
95
5
10
1200
25
0
150
50
100
220
225
5
15
120
5
130
Mini-
mum
5
5
5
5
5
5
10
420
15
0
100
50
100
100
50
5
15
100
5
130
Number of
Occurrences Mean
4 7
6
3
7
7
1
1
7
2
0
2
1
1
4
5
2
1
2
1
1
21
18
28
36
0
0
773
13
0
125
50
100
173
132
5
13
118
5
180
Maxi-
mum
10
50
35
60
120
0
0
1200
15
0
150
50
100
250
220
5
15
135
5
180
Mini-
5
10
5
10
10
0
0
440
10
0
100
50
100
100
45
5
10
100
5
ISO
Number of
Occurrences Mean
3
5
4
6
7
0
0
7
2
0
2
1
1
5
5
2
2
2
1
1
12
21
13
33
35
0
0
749
13
0
125
50
100
187
166
10
18
135
5
Maxi-
mum
20
50
20
70
90
0
0
1200
15
0
150
50
100
280
250
15
25
160
5
Mini- Number of
mum Occurrences
5
10
5
10
10
0
0
400
10
0
100
50
100
100
50
5
10
110
5
3
5
2
6
7
0
0
7
2
0
2
1
"
5
5
2
2
2
1
-
(a) Operating conditions for all filters:
Detention time - 3 days
Temperature - 34 "C
Loading - 40 to 145 Ib COD/1000 cu D-day void volume
(b) Concentrations ore as mg/1 total carbon, far factor to convert to compound see Table 37.
(c) Average of 9 feed samples, 7 effluent samples, both composite and grab.
-------
TABLE 39
EFFICIENCIES OF THREE PROCESSES IN SPECIFIC COMPOUND REMOVAL
Anaerobic Lagoon
oo
Carbon removal, %
Non-volatile acid
carbon removal, %
48 lb/1000
cu ft-day
Loading
22 lb/1000
cu ft-day
Loading
13 lb/1000
cu ft-day
Loading
32
66
37
69
47
58
Anaerobic Filter
40-145 Ib COD/
lOOOcu ft-day
Loading
31
63
Contact Digester
60-160 Ib COD/
lOOOcu ft-day
Loading
18
73
-------
SECTION XI
ECONOMIC ANALYSIS OF ALTERNATIVE ANAEROBIC PROCESSES
An economic study of the three anaerobic processes was made by a consulting
engineering firm under a subcontract to this project. The alternatives considered
included treatment of a dilute and concentrated feed (800 and 8,000 mg/liter BOD)
of flow rates of 1 and 10 million gal/day for dilute waste water and 10 to 100
thousand gal/day for concentrated wastes. A summary of the wastewater flow and
BOD concentration for each of the twelve design cases is shown in Table 40. The
basic design parameters used in the comparison are listed in Table 41. A bio-
chemical oxygen demand reduction of 50 and 80% was assumed, respectively, for
dilute and concentrated wastes for all types of treatment. Estimates were based on
laboratory data and were not necessarily confirmed by pilot studies. Assumptions
made in developing the process designs are summarized in Table 42.
Anaerobic Processes
Estimates of the capital cost for the four design cases of each of the three anaerobic
process alternatives are graphically presented in Figure 34. These costs are present-
ed as unit capital costs ($/lb BOD5 removed/day) in Figure 35. The cost estimates
include equipment, materials, and labor costs for construction of the processes under
consideration, but do not include certain project costs, such as costs for engineering
or for a control building, which depend upon the type of additional facilities to be
built as a part of the waste treatment system. The two more sophisticated processes
(anaerobic filter and anaerobic contact) are much more costly than is the anaerobic
lagoon process for both concentrated and dilute wastewaters.
Although annual operating costs were not estimated in this study for the individual
anaerobic processes, the differences in these costs for the three anaerobic processes
considered may be discussed in qualitative terms. Of the three processes, the
anaerobic lagoon is the least expensive to operate since it requires no power, no
operation as such, minimum lab analyses, and minimum maintenance. The anaerobic
contact process is the most expensive to operate because it requires recycle and
considerable analytical data to maintain a given level of treatment. Also,
maintenance costs will be greater for this process, since it requires more mechanical
equipment.
119
-------
TABLE 40
SUMMARY OF WASTEWATER FLOWS AND BOD5 CONCENTRATIONS
FOR ECONOMIC COMPARISONS
Case No.
Flow, gpd
BOD5/ mg/l
Anaerobic Filter Process
Dilute Wastewater
Concentrated Wastewater
Anaerobic Contact Process
Dilute Wastewater
Concentrated Wastewater
Anaerobic Lagoon
Dilute Wastewater
Concentrated Waste wafer
1
2
3
4
5
6
7
8
9
10
11
12
10,000,000
1,000,000
100,000
10,000
10,000,000
1,000,000
100,000
10,000
10,000,000
1,000,000
100,000
10,000
800
800
8,000
8,000
800
800
8,000
8,000
800
800
8,000
8,000
120
-------
TABLE 41
DESIGN PARAMETERS FOR ECONOMIC COMPARISONS
Dilute Concentrated
Waste water Waste water
BOD Loading (a)
lb/1,000 cu ft/day
Anaerobic Filter Process 47 210
Anaerobic Contact Process 31 100
Detention Time (a), days
Anaerobic Lagoon Process 8 40
Treatment Temperature, °C
Anaerobic Filter Process 20 35
Anaerobic Contact Process 20 35
Anaerobic Lagoon Process 20 20
BOD Removal, percent 50 80
(a) Based on influent flow.
121
-------
TABLE 42
LIST OF MAJOR ASSUMPTIONS FOR ECONOMIC COMPARISONS
1. The wastewaters to be treated are not inhibitory.
2. Any pumping, pretreatment (e.g. neutralization, grit removal, equalization,
or nutrient addition), or second-stage treatment should be comparable for the
three alternatives; therefore, they need not be considered in this comparison.
3. The facilities are to be located in a warm climate such as in Texas, and the
raw wastewater temperatures are assumed to be between 25 and 35 °C.
4. Sulfates present in the wastewaters will be reduced to sulfides during
anaerobic treatment. Some of the sulfides will be precipitated as heavy
metal sulfides, thereby reducing toxicity attributable to the heavy metals.
The remaining sulfides will be distributed between the liquid and gaseous
phases as h^S. It is assumed that no special problems will be caused by the
hydrogen-sulfide in the digestion gas based on observations of no-odor
problems during laboratory investigations.
122
-------
FIGURE 34
CAPITAL COST ESTIMATES
ANAEROBIC TREATMENT PROCESSES
«l
42
S
O
*5.
3
£
o
IVfV.V/V
50.00
20.00
10.00
5.00
2.00
1.00
0.5
0.2 I
0.1
0.04 j
Anaerobic filter process
A Anaerobic contact process
Anaerobic lagoon process
Concentrated
Waste waters
BOD5 = 8000 mg/l
1
X
X
X
X ^
S 4*
^
-"
1
Dilute Wastewaters
BOD5 =800mg/l
AS*
/'
/
X
X
X
x
X
X
X
f
.01 0.1 1.0 10.(
Flow, mgd
123
-------
FIGURE 35
CAPITAL COST ESTIMATES
ANAEROBIC TREATMENT PROCESSES
1000
Anaerobic filter process
A Anaerobic contact process
Anaerobic lagoon process
500
o
o
oo
200
^ 100
3 <
s.
'a.
8
Concentrated x,
Wastewaters x-
BOD5 = 8000 mg/l Xl
20
Dilute Wastewaters
BOD5 = 800 mg/l
0.01
0.1
1.0
10.0
Flow, mgd
124
-------
SECTION XII
ACKNOWLEDGEMENTS
This project was completed by the Research and Development Department of Union
Carbide Corporation, Chemicals and Plastics Division under the general direction
of Mr, R. A. Conway. Bench and semi-pilot scale experimentations were
conducted by Mr. J. A. Fisher. Demonstration scale studies were conducted by
Mr. J. C. Hovious who also prepared the final project report. Mr. G. W. Kumke,
currently with Union Carbide International Division, provided valuable technical
input to the project.
The contributions of Messrs. J. F. Erdmann, A. R. Pettyjohn, Z. B. Harvey,
Ca R, Ganze, R. Connor, and Miss C. R. Hester of the Texas City Plant,
Mr. G. M. Alsop, Mr. A. H. Cheely, Mr. J. F. Dietrich and Mrs. Jackie Gray
of the South Charleston Technical Center, and Mr. J. A. Horn, EPA Project
Officer, are gratefully acknowledged.
Dr. P. L. McCarty of Stanford University, Dr. J. W. Vennes of the University
of North Dakota, and Roy F. Weston Company provided valuable technical
assistance as consultants. The loan of a surface aerator by the Ashbrook
Corporation for pilot scale studies is gratefully acknowledged.
125
-------
SECTION XIII
REFERENCES
1. Payne, R. A., Kumke, G. W., and Cheely, A. H., Journal WPCF, 17, 4,
535 (1969). ~~
2. Kumke, G. W., Hall, J. F., and Oeben, R. W., Journal WPCF, 40, 8,
Part 1, 1408 (1968). ~~
3. Hovious, J. C., Conway, R. A., and Harvey, Z, B., "Pilot Studies of
Biological Alternatives for Petrochemical Waste Treatment," Presented at
26th Purdue Ind. Waste Conf., May 4-6, 1971.
4. Painter, H. A., Water Research, 4, 393 (1970).
5. Stonier, R, Y,, Doudorff, M., and Adelbery, E. A., The Microbial World,
2nd Ed., pp 259-283, Prentice-Hall, Inc., Englewood Cliffs, N. J. (1963).
6. McCarty, P. L., and Young, J. C., Journal WPCF, 39, 8, 1259 (1967).
7. McCarty, P. L., Public Works, 95, 9, 107; 10, 123; 11, 91; 12, 95 (1964).
8, Smith, P. H,, "Pure Culture Studies of Methanogenic Bacteria," Proc. 20th
Ind. Waste Conference, Purdue University Ext. Ser. 118, 583 (1966).
9. Schroepfer, G. J., and Ziemke, W. R., Sewage and Industrial Wastes, 31,
164 (1959).
10. Young, J. C., and McCarty, P. L., "The Anaerobic Filter for Waste
Treatment," Technical Report 87, FWPCA Grant WP-00585, Sept. 1963 -
Feb. 1967, Dept. of Civil Engineering, Stanford University, March 1968.
11. Pfeffer, J. T., "Anaerobic Lagoon-Theoretical Considerations," Proc. 2nd
International Symposium for Waste Treatment Lagoons, R. E. McKinney, ed.
1970.
12. Fisher, J. A., Hovious, J. C., Kumke, G. W., and Conway, R. A.,
Water-1970, AlChE Chemical Engineering Process Symposium Series, 67,
107 (1971). ~~
127
-------
13. Gloyna, E. F., and Espino, E., Journal San. Eng. DIv., ASCE, 95, SA3,
607 (1969).
14. Holm, H. W., and Vennes, J. W., Applied Microbiology, ^9, 988 (1970).
15. Brady, D. K., Graves, W. L., Jr., and Geyer, J. C., "Surface Heat
Exchange at Power Plant Cooling Lakes," Cooling Water Studies for Edison
Electric Institute, Research Project RP-49, The Johns Hopkins University,
Baltimore, Md., 97, 1969.
16. Chen, R. Y., and Morris, J. C., "Oxidation of Aqueous Sulfide by Op
1. General Characteristics and Catalytic Influences," presented at 5th
International Water Pollution Research Conference, July 1970.
17. Hansen, S. P., Culp, G. L., and Stukenberg, J. R., Journal WPCF, 41,
8, 1421 (August 1969).
18. Lawrence, A. W., McCarty, P. L., and Guerin, F. J. A., Int. Journal Air
Water Pollut., 10, 207, 1966.
19. Andrews, J. F,, Journal San. Eng. Div., ASCE, 95, SAI, 95 (1969).
20. Dague, R. R., Journal San. Eng. Div., ASCE, 95, SA6, 1194 (1969).
21. Standard Methods for the Examination of Water and Wastewater, 12th ed.
Am. Public Health Assoc. Inc., New York (1965).
22. Methods for Chemical Analysis of Water and Wastes, Environmental
Protection Agency, Water Quality Office, Analytical Quality Control
Laboratory, Cincinnati, Ohio (1971).
128
-------
SECTION XIV
LIST OF PUBLICATIONS
1. FisheivJ. A., Hovious, J. C., Kumke, G. W., and Conway, R. A.,
"Pilot Demonstration of Basic Designs for Anaerobic Treatment of Petro-
chemical Waste," Water-1970, AlChE Chemical Engineering Progress
Symposium Series, 67, 107 (1971).
2. Hovious, J. C., Conway, R. A., and Harvey, Z. B., "Pilot Studies of
Biological Alternatives for Petrochemical Waste Treatment," Presented at
26th Purdue kid. Waste Conf., May 4-6, 1971.
3. Hovious, J. C., Conway, R. A., and Ganze, C. W., "Anaerobic Lagoon
Pretreatment of Petrochemical Wastes," Presented at 44th Annual WPCF
Convention, October 3-8, 1971.
129
-------
SECTION XV
GLOSSARY
Aerobic Respiration - Biological oxidations in which molecular oxygen is the
ultimate electron acceptor.
Aerobic Stabilization - Aerated biological process operated without solids
sedimentation within process and without organism recycle.
Algae - Simple plants containing chlorophyll and capable of photosynthesis.
Anaerobic Respiration - Biological oxidations in which an inorganic compound
other than molecular oxygen is the ultimate electron acceptor.
Area I Loading - Loading computed on the basis of weight organic applied per
unit surface area per unit time.
BOD, BOD5 - Five-day biochemical oxygen demand. Unless otherwise specified
BUD Indicates five-day BOD.
BOD2Q ~ Long-term BOD exerted during 20 days' incubation.
BOD-r - Total BOD including that exerted by suspended solids; five-day
incubation time unless otherwise specified.
BODp - Filtered BOD without suspended solids effect; five-day incubation
time unless otherwise specified,
Biomass-Biosolids - Heterogeneous growth of bacteria, fungi, protozoa, and
rotifers existing in biological treatment system.
CODf - Total COD including that exerted by suspended solids.
CODp - Filtered or soluble COD.
COD -Total Organic - COD which measures oxygen demand without sulfide
influence.
131
-------
Concentrated Lagoon Effluent- A concentrated waste which has been previously
treated in a full-scale anaerobic lagoon.
Concentrated Lagoon Feed - A concentrated waste stream (15,000 mg/l COD).
Equalization - Mixing to provide a time smoothing of variation in a waste stream.
Facultative Lagoon - A lagoon which exists with an aerobic top and an anaerobic
bottom layer.
Fermentation - Energy yielding biological oxidation-reduction reaction in which
organic compounds serve as a final electron acceptor.
Hydraulic Retention Time (HRT) - Basin volume divided by liquid flow rate.
Metabolic Intermediates - Materials arising from formation or from breakdown of
other materials in metabolism.
Methanogenic Bacteria - Obligately anaerobic bacteria characterized by an
energy yielding metabolism which results in oxidation of simple organic materials
and reduction of carbon dioxide or organics to methane.
Microaerophillic Bacteria - Bacteria which grow in the presence of minute
quantities of free oxygen.
Non-Volatile Acid Organics - A measure of organics excluding volatile acids,
computed as [Total Organic - Organic Contribution of Volatile Acids (as acetic)^.
Photosynthesis - Utilization of light as an energy source through chlorophyll for
biological synthesis^generally involving CO2 fixation as a source of carbon.
Solids Retention Time (SRT) - Average retention time of microorganisms
(Total Weight of Microorganisms/Total Weight of Solids Lost Daily)
Theoretical Oxygen Demand (TOD) - Theoretical amount of oxygen which would
be required to convert the carbon and hydrogen in a compound to their highest oxidation
state.
Thiorhodaceae - A family photosynthetic purple sulfur bacteria which anaerobically
use carbon dioxide as a carbon source and hydrogen sulfide as a source of energy.
132
-------
Volatile Acids - Short chain fatty acids detected by the column chromatographic
method described in Standard Methods (21).
Volumetric Loading - Loading computed on the basis of weight organic per unit
volume of reactor per unit of time.
133
-------
APPENDIX I
PILOT PLANT OPERATING DATA
135
-------
1700
1600
1500
1400
1300
1200
1100
1000
s 900
O 800
700
600
500
400
300
200
100
0
Feed to Anaerobic Basins
- A Effluent '1 (East, Deep)
O Effluent '2 (West, Shallow)
Feed Started
' to System
10
15
FIGURE 36
ANAEROBIC LAGOON PERFORMANCE, AUGUST-SEPTEMBER 1970
20
25
30
10
AUGUST, 1970
15 20
SEPTEMBER, 1970
25
30
-------
FIGURE 37
ANAEROBIC LAGOON PERFORMANCE. OCTOBER-OfCEMBER 1970
MOO
1300
1200
1100
1000
900
r800
|" TOO
600
500
400
300
200
100
0
Feed to Anoerob't Basins
- < Effluent '1, (East. Deep)
O Effluent '2, (West, Shallow)
10 15
OCTOBER, 1970
NOVEMBER, 1970
15 20
DECEMBER, 1970
-------
FIGURE 38
ANAEROBIC LAGOON PERFORMANCE, JANUARY-MARCH 1971
CO
00
to Anoeroblc Btnlra
A Efflu.nl't (6.1,
O Effluent '2 (W«lt, (holloa)
JANUAftY, 1971
19 20
F£WUA«Y, 1971
-------
CO
2200
2100
2000
1900
1800
1700
1600
1SOO
MOO
1300
1200
1100
1000
900
a
700
600
500
400
0
Feed to »n>eroblc basins
Effluent No. 1 (East, deep)
Effluent No. 2 (ve»t, ihillow)
FIGURE 39
ANAEROBIC IAGOON PERFORMANCE, APRIL-JUNE 1571
-4-
APSIL, 1971
10 15
MAY, 1971
15
JUNf, 1971
-------
TABLE 43
ANAEROBIC LAGOON DATA
Day
io/ \fm
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Amroblc
Benin
l?a> 2'
7.4
7.8
7.6
7.4
7.4
7.5
7.5
7.4
7.4
7.6
7.6
7.4
7.4
7.4
7.2
7.2
7.4
7.5
7.2
7.1
7.1
7.1
7.3
7.3
7.3
7.3
7.3
7.3
7.1
7.5
7.0
7.7
7.8
7.8
7.7
7.8
7.7
7.9
7.8
7.8
7.6
7.6
7.4
7.6
7.5
7.4
7.4
7.8
7.8
7.6
7.3
7.5
7.5
7.6
7.5
7.7
7.6
7.4
7.4
7.6
7.8
7.6
Anaerobic
Benin
Tp^
26
28
29
29
28
29
29
28
26
25
25
24
25
26
25
25
25
26
24
26
26
26
26
27
26
27
27
26
24
23
24
26
28
29
29
28
29
29
28
26
25
24
24
25
26
25
25
25
26
2$
26
26
26
26
27
26
27
27
26
24
23
24
Anaerobic food
COD
1170
1060
--
--
1125
925
1210
~
1390
--
-.
1140
_
1110
~ '
1140
~
TSS
23
_
28
--
42
59
20
~
37
--
28
~
~
30
36
vss
14
__
16
r
17
35
16
~
27
15
41
17
BOOS
580
440
__
570
--
500
420
~
680
800
690
442
~
451
--
VA
105
__
130
105
--
110
«
--
190
--
~
120
108
120
A Ik.
580
110
120
360
380
250
120
180
100
110
180
210
320
180
200
180
260
230
210
80
120
145
ISO
210
280
260
270
270
220
220
220
COO
520/325 (b)
555/325
~
440/305
-
475/315
425/250
370/290
«
660/560
66-/370
~
735/435
~
Ne.
TSS
150
136
--
72
77
64
«
74
~
~
68
~
176
~
--
88
1 Lagoon Cfftmnt
VSS
130
94
--
48
--
63
52
--
57
~
52
~
--
130
61
~
BOD5
122
184
157
140
~
102
--
110
100
~
315
~
--
129
144
VA
230
240
250
230
245
«
275
«
~
290
~
265
--
Alk.
580
590
580
600
660
670
670
670
560
680
700
520
550
500
480
510
580
480
520
510
560
570
580
580
580
600
600
580
540
600
COD
585/465(b)
535/430
480/370
590/360
495/J85
--
435/355
~
555/400
--
550/395
'
695/435
No. 2 Lagoon Efflutnt
TSS
156
126
70
59
--
45
77
«
72
~
92
~
76
--
VSS BODj
134
86
48
--
39
--
33
--
57
61
~
74
--
54
195
138
192
~
160
~
114
125
~
134
~
~
325
~
~
228
~
VA
240
225
~
~
210
~
200
~
~
225
«
265
--
«
«
~
228
~
Alk.
580
700
700
680
720
740
740
740
660
680
660
610
580
540
530
560
590
560
600
680
690
690
700
680
680
660
670
670
680
690
(a) Number 1 Lagoon is 12 feet deep. Number 2 is 6 feet deep
(b) Total/Filtered
(c) Units are as in Table 7
(conHnund)
-------
ANAEROBIC LAGOON DATA (continued)
AnMrabfe
Borin
PH
Day
11/1/70
2
3
4
5
6
7
8
9
10
11
12
13
14
IS
14
17
18
19
20
21
22
23
24
25
26
27
28
29
30
I (<>)
7.3
7.5
7.5
7.4
7.2
7.1
7.1
7.1
7.4
7.5
7.4
7.4
7.5
7.5
7.6
7.6
7.4
7.4
7.4
7.3
7.2
7.4
7.4
7.3
7.4
7.1
7.0
7.1
7.1
7.2
2
7.5
7.4
7.8
7.7
7.2
7.3
7.3
7.3
7.4
7.6
7.5
7.5
7.5
7.6
7.7
7.6
7.5
7.6
7.3
7.5
7.4
7.6
7.3
7.4
7.0
7.0
7.3
7.3
7.3
7.3
AmtraMc
Benin
^*SF
24
24
20
20
22
19
19
20
22
22
23
23
23
21
20
20
20
20
21
21
21
22
22
18
18
18
20
21
21
21
24
24
19
19
20
21
21
23
22
22
23
23
22
17
17
16
17
17
18
18
19
20
20
16
16
17
18
19
19
19
Antmobie Food
COD
._
900
--
~
1005
940
960
--
1260
~
1040
--
~
1120
~
955
~
1075
--
--
1030
~
TSS
_
45
«
142
*»
26
--
39
52
28
32
--
21
52
vss
..
22
~
~
--
112
16
~
--
20
--
20
22
~
_
18
14
20
~
--
BODj
_
425
--
~
420
--
-
455
~
521
590
--
410
--
452
_
380
--
610
410
VA
_
ISO
--
120
228
_
no
~
96
Alk.
280
140
120
145
160
280
200
210
180
160
120
145
200
290
150
190
130
120
220
100
120
130
200
480
210
100
92
110
120
ISO
COD
..
440/915
~
~
475/345
--
330
--
460/350
--
885/600
--
505/415
4X5/370
--
~
37S/K5
~
415/305
.
--
69S/-
~
No.
TSS
..
110
~
~
106
70
104
«
~
82
72
~
71
78
~
84
~
--
54
«
1 lagoon Efflucnf
VSS BOD5
..
66
~
--
68
~
~
46
72
~
54
_
42
--
61
38
~
68
~
~
22
..
130
145
~
92
.
125
«
~
186
~
114
~
~
113
..
135
151
230
VA
325
~
265
~
120
--
~
~
~
~
260
~
60
--
.--
~
Alk.
580
370
510
520
580
500
510
500
560
580
560
430
450
450
460
450
450
510
380
400
410
480
330
340
380
300
280
300
310
360
COD
..
550/385
~
585/495
470/
655/510
1080/330
685/500
640/510
-.
_
565/530
~
_
420/385
«
.
760/620
~
No.
TSS
..
146
~
117
«
70
94
74
~
76
~
--
66
_-
82
--
..
68
«
58
«
2 lagoon Effluwif
VSS
..
103
~
«
88
--
«
48
32
~
~
44
--
42
50
..
-.
46
~
50
--
~
32
~
BODj
.
195
~
"
210
~
~
160
186
268
169
_
235
134
..
165
240
--
VA
._
180
90
~
..
^.
215
~
..
84
--
Ak.
620
570
550
540
500
520
580
610
620
540
550
550
510
460
510
590
480
480
490
610
620
620
610
380
360
380
380
400
(a) Nutter 1 Lagoon ! 12 foot anp, Nuntor 2 ii 6 feet OMB.
(continued)
-------
ANAEROBIC LAGOON DATA (continued)
Pay
12/ 1/70
2
3
4
5
6
7
8
9
10
It
12
13
14
IS
16
17
18
19
20
21
22
23
24
25
26
27
28
»
30
31
Anaerobic
Benin
3*4:
7.1
7.0
7.0
7.2
7.2
7.0
7.3
7.4
7.3
7.3
7.1
7.2
7.1
7.1
7.2
7.1
7.2
7.2
7.2
7.4
7.2
7.4
7.4
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.3
7.4
7.4
7.3
7.5
7.5
7.2
7.5
7.6
7.6
7.6
7.4
7.4
7.4
7.4
7.4
7.4
7.3
7.4
7.4
7.6
7.4
7.7
7.7
7.5
7.4
7.7
7.6
7.5
7.5
7.5
7.6
Anaerobic
Bailn
J*-f
21
22
22
22
22
21
20
19
21
21
19
18
17
17
17
18
18
18
22
24
24
24
23
19
20
18
20
20
22
22
19
20
21
21
21
21
19
18
18
20
20
18
18
16
16
16
17
17
17
21
23
23
23
22
18
19
18
20
20
22
22
19
Anaerobic Feed
COD
965
1160
--
1070
--
1140
~
--
1220
--
--
1230
--
--
1160
1040
-
~
1060
--
1040
~
905
TSS
48
--
36
~
68
~
72
56
~
~
72
«
58
«
72
~
~
46
«
64
52
VS5
30
--
18
--
24
-.-
28
12
32
22
~
58
--
24
38
«
--
40
BOD;
527
660
~
652
«
637
--
--
390
--
--
687
575
~
480
~
535
~
480
--
~~
VA Alk.
160
- 160
200
~ 200
70
44
250
-- 210
180
200
~ 180
210
260
200
100
110
350
260
320
150
260
180 200
200
220
120
240
-- 210
- 210
- 120
- 140
160
COD
735/675
785/695
675/630
--
695/610
--
645/545
~
--
630/610
665/590
-.
595/540
-
« -
575/490
--
565/490
460/380
(continued)
No.
TSS
64
66
64
--
84
~
104
104
--
72
--
90
«
70
82
~
74
1 Lagoon Effluent
VS5 8OD,
40
30
~
20
~.
44
36
--
~
56
--
42
~
58
48
~
57
~
~*
202
246
~
201
--
~
288
--
198
272
~
250
_
188
~
172
«
150
~
--
~~
VA Alk.
360
340
380
380
380
400
490
480
- 450
- 460
480
500
-- 520
520
540
- 520
530
580
570
530
~ 560
250 540
570
480
500
480
- 460
132 460
480
- 500
500
COD
630/530
590/480
~
605/515
590/495
--
465/400
.
570/460
~
S70/475
--
565/480
--
~
435/J65
~
~
385/330
460/345
No.
TSS
58
-.
88
60
--
80
--
--
88
96
78
--
-.
92
80
--
~
86
~
94
2 Lagoon Effluent
VSS BOO.
34
-.
44
-.
28
40
40
..
52
..
50
--
..
72
~
60
--
~
54
«
~
62
219
..
255
203
-.
292
~
170
..
250
150
_
176
126
--
~
114
~
~
VA Alk.
420
410
400
590
610
480
600
650
650
560
550
540
580
580
560
550
550
580
590
620
580
230 550
10
490
520
500
570
108 580
560
560
570
-------
ANABtOBIC LAGOON DATA (eenHnuKl)
Day
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
AKMroblc
Botln
7.3 7.7
7.2 7.4
7.3 7.3
7.3 7.3
7.7
7.6
7.6
7.5
7.5
7.1
7.1
7.1
7.2
7.3
7.4
7.5
7.5
7.4
7.3
7.2
7.1
7.2
7.2
7.2
7.0
6.8
6.5
6.9
7.0
6.9
7.2
7.5
7.3
8.2
7.7
7.8
7.3
7.3
7.2
7.3
7.3
7.2
7.1
7.2
7.2
7.3
7.3
7.3
7.2
7.2
7.2
7.0
6.9
6.7
7.0
7.1
7.0
7.2
Anaerobic
latin
Temp.. *C
1
18
19
18
17
14
10
9
13
13
15
18
19
21
21
20
19
20
20
19
20
20
20
20
20
20
22
19
20
21
22
22
2
18
19
18
17
14
.10
9
9
10
14
17
19
20
21
20
19
19
19
18
19
20
20
19
19
20
21
18
19
20
21
21
COD
865
--
735
~
--
1080
--
--
1055
--
--
895
«
765
--
~
840
~
670 '
--
855
--
--
810
Anaerobic FMd
TSS
48
36
~
50
~
~
56
42
44
~
44
~
42
~
38
~
--
36
~
VSS
30'
20
~
~
30
--
16
--
18
~
30
~
34
«
26
~
--
26
~
2
BOD5
462
392
532
440
--
459
-.
330
--
350
«
345
450
~
«
442
VA
..
144
192
--
152
.
~
110
~
180
Alk.
100
120
140
150
50
120
160
200
160
230
Nil
Nil
260
150
100
185
140
100
150
120
150
180
160
140
140
100
100
210
230
130
210
COD
395/345
_
415/405
..
605/530
715/665
..
595/535
..
570/560
-.
-.
645/605
--
630/545
~
635/570
--
~
625/545
No.
TSS
68
..
48
64
~
70
..
..
70
..
..
58
..
56
40
«
54
--
42
1 Lagoon Effluent
VSS BODs
40 126
..
26
..
36
-.
34
..
..
28
..
..
36
..
_
42
_
_
26
~
38
38
_
154
..
_.
168
-.
180
..
_
186
..
_
162
..
_.
131
..
206
..
~
222
274
VA
_
144
..
~
~
150
~
_
.-
_
..
__
._
..
260
~
202
Alk.
510
500
510
510
550
530
530
570
540
510
510
490
480
500
510
530
530
510
380
380
350
380
390
400
350 '
350
360
340
380
340
410
COD
290/215
..
525/455
..
520/470
-.
548/590
-.
_.
570/505
_
__
640/620
..
655/565
555/470
650/590
655/595
No.
TSS
72
..
64
_
__
56
..
..
70
..
..
60
__
...
62
_.
_.
62
..
42
..
..
38
..
34
> 2 Lagoon Effluent
VSS
44
__
40
..
_.
30
..
36
._
..
26
._
..
38
..
_.
46
..
26
24
_
22
99
*.
152
..
. ..
165
_
-_
148
__
171
..
..
276
..
207
..
148
__
216
..
..
220
VA
180
..
185
._
190
H
_.
..
_
..
*
^.
..
..
..
..
_
H
245
.H
192
Alk.
610
520
480
410
450
450
550
500
490
510
530
490
530
420
410
400
410
400
420
420
370
290
420
410
270
300
300
330
330
310
400
(continued)
-------
ANAEROBIC LAGOON DATA (conrimnd)
Doy
2/1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Anaerobic
Bnln
7.2
7.6
7.6
7.4
7.5
7.2
7.1
6.5
6.6
6.9
7.0
7.1
7.1
7.1
7.1
7.0
6.9
6.9
7.0
6.9
6.9
6.9
7.0
7.1
7.1
7.0
6.9
6.9
7.2
7.6
7.6
7.5
7.4
7.3
7.0
6.4
6.5
6.8
7.0
7.0
7.2
7.2
7.2
7.0
6.9
7.0
7.1
7.0
7.0
7.0
7.2
7.3
7.3
7.3
7.1
7.0
Anaerobic
Bailn
Temp., *C
19
17
19
19
18
18
17
14
14
15
15
16
16
15
14
20
21
21
22
22
20
18
17
17
19
18
19
21
18
16
18
19
17
17
16
13
13
14
14
15
16
15
15
19
20
20
21
21
19
17
15
16
18
15
17
20
Anaerobic Feed
COD
785
835
855
1070
870
900
~
1000
-T
~
1170
~
1030
--
TSS
40
36
50
48
42
--
80
--
48
69
--
47
--
VSS
20
22
40
28
--
30
--
56
30
~
~
48
~
--
37
--
BODj
442
320
265
405
375
392
352
412
~
«
415
VA
--
108
--
-
--
--
132
144
Alk.
220
380
190
200
260
460
Nil
Nil
400
390
120
180
280
410
450
480
430
450
400
320
220
400
550
370
400
390
140
80
COD
615/590
680/635
595/555
630/605
--
685/645
680/660
~
645/620
«
~
690
~
--
715/
--
No.
TSS
42
48
78
40
--
62
--
--
62
--
-
46
~
~
50
--
~
60
~
1 Lagoon Effluent
VSS
32
34
64
26
48
~
40
~
30
«
38
--
38
--
BODj
219
259
202
262
140
~
120
168
219
~
«
198
VA
~
180
~
~
~
~
~
420
205
~
Alk.
400
440
450
400
360
430
450
410
400
460
480
480
460
485
400
380
340
360
370
340
360
380
400
400
400
390
370
360
COD
600/555
615/580
535/490
300/565
--
655/610
--
~
630/575
593/575
625/
~
645/
~
No.
TSS
32
34
68
48
..
54
--
76
--
80
50
--
56
~
«
2 Logoon Effluent
VSS
24
22
52
30
52
«
28
--
--
62
40
--
~
38
-
BODj
204
223
214
259
138
-.
102
168
~
172
178
«
VA
_
156
--
..
.-
_
398
192
~
Alk.
390
400
380
360
340
360
370
310
350
380
400
420
430
440
370
370
330
360
380
340
380
380
410
400
430
360
360
360
(continued)
-------
ANAEROBIC LAGOON DATA (continued)
Day
3/1/H
3
4
5
&
7
8
9
10
II
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Amrebic
Benin
7.0 7.1
6.7 6.8
7.1
7.1
7.0
6.9
7.0
7.1
7.2
7.0
7.0
7.0
7.0
6.9
6.9
6.8
6.1
7.2
7.1
7.1
7.3
7.3
7.3
7.2
7.2
7.3
/.2
7.2
7.1
7.4
7.3
7.2
7.2
6.9
7.0
7.1
7.2
7.4
7.2
7.1
7.2
7.0
7.1
7.0
7.0
7.0
7.3
7.0
7.3
7.4
7.2
7.5
7.4
7.4
7,5
7.4
7.7
7.2
7.6
7.4
Anaerobic
Bnln
fSF
22 21
22 21
14
13
12
14
16
18
18
19
20
21
22
24
22
23
25
21
18
18
20
22
21
18
19
17
21
22
23
20
22
19
12
11
13
IS
17
17
18
19
20
20
23
20
21
24
23
20
17
17
19
21
17
18
16
20
21
22
19
21
Anwroblc Fwd
COO
856
--
925
845
«
1060
--
970
~
-.
910
~
980
1115
~
1080
1020
~
1450
TSS
48
44
46
--
34
56
~
54
-.
48
58
-.
46
-.
44
«
54
vss
32
--
32
~
32
~
28
--
34
--
«
30
-~
38
~
46
30
~
22
~
--
32
BODj
367
492
«
532
582
530
--
455
--
~
400
415
--
365
--
666
--
710
VA
208
157
..
208
~
208
~
«
216
144
144
«
216
264
.-
180
Alk.
240
280
450
450
350
400
360
400
440
410
430
4iO
390
400
170
410
400
390
350
280
640
400
480
380
410
470
400
300
580
420
COD
660/585
600/652
~
635/555
--
--
600/605
--
650/575
715/625
560/540
..
655/585
-.
770/705
~
675/600
~
~
820/935
No.
TSS
68
--
68
«
50
~
--
36
~
72
--
~
70
44
-.
44
38
~
~
40
-.
58
1 lagoon Effluent
VSS BOD5
36 188
~
56
~
~
38
...
30
-.
..
50
.-
-.
50
~
38
~
.
36
..
~
28
.-
38
.-
«
42
~
208
~
~
273
.-
312
.-
231
264
~-
303
_
182
..
246
262
~
303
VA
--
208
~
157
220
--
372
~
276
228
..
144
216
~
~
288
96
AUT.
350
340
370
370
380
380
410
450
450
460
450
440
370
450
440
420
410
450
480
500
560
500
480
540
540
600
570
600
590
610
610
COD
595/550
--
645/540
~
655/515
--
~
575/525
«
--
550/490
«
635/520
~
620/550
«
57S/
~
680/590
~
~
600/520
~
775/650
No.
TSS
82
78
~
«
50
«
--
40
76
100
-.
~
84
..
60
--
.-
50
~
--
46
--
70
2 Laooen Effluent
VSS
58
~
44
.-
18
«
34
~
--
54
78
~
«
74
..
48
.-
38
~
>.
44
»
52
BODj
160
^_
«
169
.-
286
~
--
266
162
~
~
262
240
..
174
189
247
..
279
VA
157
208
«
220
--
~
312
--
264
~
180
..
192
_
204
240
_.
..
120
A St.
350
340
390
370
380
410
420
450
450
450
450
450
380
450
430
440
430
460
500
560
580
530
490
560
560
510
600
600
600
610
620
-------
ANAEROBIC LAGOON DATA
Doy
Aimroblc
Bain
4/1/71
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
7.3
7.3
7.4
7.3
7.2
7.2
7.2
7.3
7.2
7.2
7.8
7.4
7.4
6.8
7.0
7.1
7.2
7.2
7.6
7.6
7.5
7.5
7.5
7.4
7.4
7.3
7.5
7.5
7.4
7.5
7.5
7.5
7.5
7.5
7.3
7.6
7.3
7.4
7.3
7.4
7.8
7.6
7.6
7.0
7.1
7.3
7.4
7.4
7.8
7.8
7.5
7.5
7.8
7.4
7.5
7.4
7.6
7.6
7.6
7.6
21
19
18
18
19
19
18
21
21
22
22
22
23
23
24
23
23
23
23
23
24
22
24
26
25
25
26
25
24
24
20
19
17
17
18
17
16
19
20
21
21
21
21
21
23
22
22
22
22
22
24
22
23
24
24
24
24
24
24
23
AnoM-oblc FMd
COD
_.
--
1310
«
1300
--
--
1350/1260
--
1030/945
~
1680
~
--
1630
1250
..
2050
1900
2160
TSS
60
_
56
--
58
~
58
86
56
'
66
68
68
66
VSS
._
38
--
40
54
42
~
78
~
45
44
42
42
46
BO05
__
~
775
~
_
610
~
-.
627
502
580
567
477
_
612
~
672
VA
252
--
240
288
192
~
215
--
--
252
445
~
418
--
384
Alk.
380
520
120
480
280
540
800
300
400
250
290
250
250
Nil
260
660
340
380
530
370
360
360
450
340
430
480
450
400
450
470
COD
830/715
885/780
730/890
770/765
-
--
950/
~
995
«
705/565
--
960/780
~
1055A55
--
1140/1030
No.
IbS
_.
76
58
52
76
~
60
72
~
60
58
60
~
62
1 Ugoon EFFttonr
VSS
».
60
--
46
~
40
58
~
40
60
~
52
~
46
--
38
~
52
BO05
..
«
366
372
319
~
284
--
292
-
~
303
162
--
306
~
432
-
«
~
VA
H.
228
~
288
--
«
312
--
228
230
~
«
192
~
336
--
--
396
--
336
Alk.
630
750
760
800
780
770
800
780
800
750
740
740
730
600
610
650
680
680
730
680
670
670
730
790
860
820
860
850
890
870
COD
_..
760/580
795/715
715/595
660/590
--
--
810
~
905
505/465
--
765/720
970/030
~
~
870/^25
No.
TSS
._
76
56
~
70
-.
66
82
~
96
56
«
-'-
52
--
68
~
68
2 Lopoon EfFlucnr
VSS BODS
~-
60
..
44
--
58
~
.-
56
62
86
_
50
~
46
48
~
--
56
..
240
300
~
271
166
--
-.
219
«
~
278
146
286
--
324
VA
..
~
264
276
~
_
252
«
_
168
--
--
~
170
192
~
324
«
118
--
~
348
Alk.
660
no
810
780
680
720
740
750
750
730
740
740
730
620
640
750
760
770
760
700
700
700
730
740
750
820
800
830
860
840
(continued)
-------
ANAEROBIC LAGOON DATA (continued)
Anaerobic
Bailn
5/ 1/71 7.3 7.4
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
7.2
7.2
7.1
7.1
7.4
7.2
7.2
7.2
7.2
7.5
7.3
_ 7.5
7.5
7.5
7.4
7.2
7.0
7.1
6.7
6.4
6.7
6.2
6.9
6.8
7.2
7.4
7.4
7.2
7.2
7.2
7.3
7.5
7.4
7.3
7.1
7.6
7.5
7.6
7.6
7.6
7.7
7.6
7.5
7.2
7.5
7.0
7.2
7.1
6.9
7.0
6.3
6.5
6.8
7.1
7.5
7.6
7.6
7.4
7.4
7.5
Anaerobic
Benin
24 23
24
24
25
26
26
26
26
24
25
24
25
25
26
26
26
26
27
27
26
26
25
27
27
27
27
27
27
27
27
27
23
23
26
25
25
25
25
25
26
26
26
26
27
27
27
29
27
27
26
26
25
27
27
27
27
27
27
27
27
27
Anaerobic reed
COD
1550
~
~
1940
1835
2040
~
1910
~
~
1400
~
1740
~
-.
1360
1500
1420
TSS
~
60
86
~
84
72
72
~
74
114
102
62
50
VSS
40
~
48
-.
50
52
56
~
60
~
84
80
52
~
40
r1
730
860
~
Broke
_
Broke
_
990
~
~
610
~ "
«
810
~
555
~
765
~
730
VA
300
468
396
~
445
~
_
~
~
288
~
~
372
~
~
288
324
~
~
_
Alk.
280
450
480
600
390
400
340
630
360
900
410
530
400
280
480
510
500
430
480
650
520
500
640
490
420
300
280
580
540
COD
975/B90
1220/1170
--~
~
1255/1075
1070A70
895/850
~
~
830/675
~
~
945/710
940/800
~
925/895
~
90S/S43
No.
TSS
~
70
78
68
84
_
90
"
~
74
66
52
~
~
50
~
~
60
1 lagoon Effluent
VSS BOD5
58
~
54
^~
52
~
74
~
~
78
~
~
64
~
58
~_
44
~
42
~
~
50
~
532
~
561
Broke
_
Broke
_
429
360
~
370
~
371
396
~
~
545
VA
324
~
560
494
448
~
--
288
-
456
~
468
492
~
~
Alk.
840
690
720
750
800
790
740
840
840
860
900
900
910
900
900
800
820
800
790
880
850
780
750
770
760.
800
800
780
780
780
COD
900/865
~
.
V90/910
~
1070/V50
940/865
-
775/735
~
785/790
~
~
875/830
920/770
~
825/^05
~
730/710
No.
TSS
56
66
~
64
66
.
--
62
~
60
~
70
-
52
~
«
54
~
~
72
2 lagoon Effluent
VSS BOD5
44
50
--
50
_
56
~
44
~
~
52
60
~
~
50
~
50
62
~
297
310
Broke
~
Broke
427
364
~
344
~
309
336
~
450
~
VA
420
«
516
~
.
386
~
445
~
~
~
288
-*
408
--
480
~
468
Alk.
820
860
780
820
750
870
820
880
900
880
890
900
860
900
910
910
820
830
840
780
900
860
800
800
810
780
760
780
780
740
BOO
(continued)
-------
ANAEROBIC LAGOON DATA (continued)
Anaerobic
tain
«^ -r^r
6/1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
IB
19
20
21
22
23
24
25
26
27
28
29
30
7.2
7.4
7.4
7.3
7.2
7.2
7.2
7.2
7.2
7.0
7.2
7.2
7.1
7.1'
7.1'
7.2
7.2'
7.0
7.0
7.0
7.1
7.0
7.3
7.2
7.1
7.1
7.1
7.2
7.2
7.1
7.4
7.6
. 7.6
7.5
7.4
7.4
7.4
7.4
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.2
7.3
7.2
7.2
7.3
7.3
7.3
7.4
7.4
7.4
7.4
7.4
7.2
7.2
7.2
Anaerobic
tain
Temp.. *C
27
27
27
27
27
27
27
28
29
29
29
30
JO
30
30
30
30
30
29
30
30
28
28
29
29
30
30
29
29
30
27
27
27
27
27
27
27
28
29
29
30
30
30
30
30
30
30
30
29
30
30
28
26
29
29
30
30
29
29
30
Anaerobic Feed
COD
_
1325
1740
-
~ .
1570
1730
_
1550
2690
2/20
1920
2280
--
1540
TSS
72
84
88
84
80
116
~
108
116
100
132
VST
_
52
52
~
64
.
56
-1~
72
72
~
60
76
64
92
BODS
785
1090
880
1170
_
880
1790
1680
1020
1170
840
VA^
360
~
552
504
552
504
904
840
816
~
864
504
Alk.
560
580
580
460
410
520
540
550
460
400
560
500
510
560
580
460
Nil
800
780
880
900
910
900
610
580
600
600
660
560
500
COD
895/800
-
930/740
.
830/825
_
1100/1070
~~
1065/1020
1210/1 100
1180/1120
-
1110/1200
.
1390/1130
1160/1040
No.
TSS
80
80
68
58
~^-
92
~
92
100
~
~
105
108
100
1 lagoon Effluent
VSS
58
60
--
42
~
36
72
72
64
68
«
80
68
BODj
_
568
524
~
533
733
490
698
670
«
620
520
~
506
VA
328
~
576
552
600
696
744
--
744
708
744
6V6
Alk.
780
800
800
790
880
910
920
910
880
BOO
820
880
860
860
920
880
880
880
900
900
910
900
910
1060
1080
1060
1100
1060
1100
1120
COD
~
810/760
805/705
~
--
799/765
~
1020/820
_
96S/B3S
~
990/960
IWO/V90
1060/1190
1140/935
~
1070/625
~
No. 2 Lagoon Effluent
TSS
_
82
92
68
98
..
100
92
104
~
100
~
132
100
vss
_
66
_
68
.
48
_
78
..
_"
88
~
72
.
72
72
~
96
~
68
BOD5
..
542
_
475
446
663
..
432
~
_
494
510
500
430
402
VA
_
504
_
492
480
552
_
-.
600
660
672
~
660
690
660
Alk.
800
820
820
800
880
920
920
910
900
890
900
920
920
910
980
960
1000
900
920
930
930
940
920
1100
1160
1200
1200
1100
1100
1100
-------
TABLE 44
AERATED STABILIZATION DATA
Day
10/ 1/70
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
pH
7.8
7.0
7.0
7.7
7.8
7.7
7.6
7.4
7.7
8.0
7.9
7.4
7.6
7.7
7.8
7.4
7.6
7.8
7.5
7.5
7.8
7.7
7.6
7.6
7.6
7.6
7.6
7.8
7.5
7.5
7.7
Basin Condition
Temp.,
°C
23
23
24
25
25
25
26
26
25
18
20
22
24
23
23
22
20
21
18
18
20
22
23
24
24
25
25
24
20
19
18
s
D.O.(
7.6
2.6
1.0
3.6
1.2
1.4
0.8
2.6
7.2
8.0
4.8
2.8
6.6
6.8
6.0
1.8
4.0
4.8
7.1
3.6
4.2
1.8
2.1
6.0
7.8
7.8
7.6
1.5
4.0
Feed (b)
COD
TSS VSS BODf
520/323 (a) 150 130 122
535/325
184
136 94 157
(a) Total COD/filtered COD
(Jb) All units are as in Table 7
440/305 72 48 140.
475/315 77 63 102
425/250 66 52 110
370/290 74 57 100
660/560 68 52 315
660/370 176 130 129
735/435 88 61 144
(continued)
COD
290/205
/190
215/140
230/205
265/190
340/275
295/190
280/175
240/210
280/225
240/195
168/1 17
168/145
255/215
265/215
330/190
200/145
195/150
195/150
195/145
220/185
~
290/145
255/165
205/140
345/180
295/155
Effluent
TSS
__
71
45
63
57
92
68
48
55
76
40
22
24
35
35
39
26
22
49
56
52
125
82
--
(b)
vss
63
35
42
46
74
54
41
48
62
31
20
14
23
25
28
16
12
34
42
38
109
56
BOD5
69
63
23
26
18
16
42
57
36
28
30
27
26
23
26
51
45
45
48
36
54
67
67
67
69
58
22
37
41
45
50
-------
Basin Conditions
Day
ll/ V70
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
_PH_
7.8
7.8
7.6
7.7
7.7
7.6
7.2
7.6
7.3
7.6
7.6
7.6
7.3
7.7
7.7
7.7
7.8
7.8
7.6
7.3
7.4
7.6
7.5
7.6
7.6
7.4
7.3
7.4
7.6
7.6
Temp.,
°C
20
19
19
18
15
14
15
20
21
18
20
19
17
16
14
13
14
16
18
18
18
18
17
14
14
16
18
20
20
20
D.O.(b)
1.8
1.2
0.8
1.8
0.5
1.4
0.8
0.5
1.8
2.0
1.0
0.3
0.7
1.6
0.6
0.8
0.8
0.4
0.8
0.8
0.4
1.2
3.8
0.8
6.4
7.6
6.8
7,4
7.6
8.0
(b) All units mg/l.
AERATED STABILIZATION DATA (continued)
Feed
COD TSS VSS BODs
440/315 110 66 130
475/345 106 68 145
330/- 70 46 92
464/350 104 72 125
885/600 82 54 186
505/415 72 42 114
445/370 71 61 113
375/295 78 38 135
415/305 84 68 151
695/- 54 22 230-
(continued)
COD
438/210
445/300
420/310
390/205
335/195
410/295
390/310
395/320
360/235
350/250
295/225
345/315
670/440
745/490
555/390
495/365
360/117
410/270
560/
530/380
430/395
415/295
525/390
595/375
386/288
340/330
330/292
300/260
Effluent
TSS VSS
156
148
188
240
126
156
142.
140
106
94
96
118
118
116
130
132
106
98
94
102
47
88
118
102
100
124
32
122
100
60
76
66
68
80
86
90
84
86
76
74
82
80
34
62
55
62
71
92
80
64
59
62
70
66
61
107
71
118
144
132
140
132
96
212
50
40
56
90
76
66
81
60
66
56
-------
AERATED STABILIZATION DATA (continued)
Basin Conditions
Day
12/ V70
2
3
4
5
6
7
8
,9
IP
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
.EiL
7.8
7.5
7.6
7.5
7.4
7.4
7.8
7.8
7.9
7.8
7.7
7.8
7.9
8.0
8.0
7.6
7.5
7.7
7.8
8.0
7.5
8.2
8.0
7.7
7.8
7.8
7.7
7.7
7.7
7.9
7.9
(b) All
Temp./
°C
21
22
22
23
23
20
18
18
20
21
20
17
17
17
17
18
18
16
19
19
20
21
21
18
19
17
19
19
20
21
20
units mg/l.
D.O.(bj
8.2
2.6
4.8
1.0
6.2
4.6
3.8
5.6
7.0
6.2
4.2
6.5
4.6
4.0
3.8
3.6
3.8
4.0
4.4
4.0
5.2
6.4
4.6
4.0
3.2
4.8
3.0
5.6
4.6
4.2
4.0
COD
735/675
785/695
675/630
695/610
645/545
630/610
825
825
820
815
845
740
725
800
720
680
710
690
Feed
TSS VSS BOD*
64 40 202
66 30 246
64 20 201
84 44 288
104 36
104 56
198
272
150
210
225
174
204
200
186
222
162
180
210
COD,
340/200
360/200
348/215
400/270
365/245
370/187
335/250
455/240
295/215
375/215
350/215
380/215
420/310
365/295
300/245
390/310
445/310
420/255
440/310
420/315
400/270
485/300
450/280
500/335
430/350
455/350
470/390
410/275
430/310
420/305
420/320
Effluent
TSS VSS
180
152
161
184
120
128
132
173
176
208
156
128
152
164
144
168
180
208
184
176
192
256
205
260
227
-220
220+
232
240
252
222
80
100
108
136
72
80
84
107
128
144
100
92
100
108
100
116
128
156
116
112
140
180
150
186
160
165
160
170
165
185
162
64
127
90
78
72
87
83
78
37
27
42
53
93
97
123
54
56
50
55
50
53
63
59
64
65
63
59
72
106
(continued)
-------
AERATED STABILIZATION DATA (continued)
Cn
Ki
Basin Conditions
bay pH
V V
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
71 8.0
7.9
8.0
8.3
8.6
8.1
8.6
8.3
8.6
8.1
8.3
7.9
7.6
7.8
7.6
7.5
7.6
7.7
7.8
8.1
7.8
8.0
8.1
7.5
7.9
7.7
7.6
7.7
7.6
7.3
7.6
(a) All units
Temp* r
°c
18
19
19
15
8
6
5
5
9
14
15
18
19
20
20
17
16
17
10
12
14
16
17
18
19
20
17
18
19
20
20
mg/1.
D.O.(a)
2.6
6.0
5.2
5.6
8.0
7.0
3.8
4.0
4.6
4.4
5.6
8.0
4.6
5.2
3.2
4.8
5.2
4.8
3.6
4.8
5.2
4.2
3.8
5.0
4.8
4.2
3.8
2.0
2.8
3.6
3.8
COD
__
395/345
415/405
605/530
715/665
--
595/535
570/560
645/605
630/545
635/570
625/545
(b) Total/filtered BOD.
Feed
TSS
__
68
.-
48
64
__
70
70
58
__
56
40
--
54
42
VSS
__
40
26
36
34
28
36
__
42
26
38
38
BOD^
__
126
154
168
180
186
__
162
__
131
206
222
274
(continued)
COD
440/300
480/290
445/255
495/315
540/305
450/355
490/380
540/405
590/490
685/615
665/605
595/440
480/280
480/270
445/265
475/235
440/260
435/235
455/225
500/290
475/265
445/290
400/190
350/210
360/180
425/215
415/195
380/165
375/170
350/190
410/200
Effluent
TSS VSS
180
228
275
380
314
212
156
104
114
100
92
124
240
240
208
216
236
248
252
292
215
225
204
188
184
235
235
195
185
220
230
112
140
175
225
200
142
98
78
82
70
76
96
144
172
136
160
176
188
196
208
125
190
164
147
128
185
190
165
150
180
190
-------
AERATED STABILIZATION DATA (continued)
Basin Conditions
Day
2/ 1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
PH
7.2
8.1
8.1
8.4
7.8
7.7
7.7
7.8
7.7
7.8
7.6
7.7
7.8
7.8
7.4
7.0
7.0
7.1
7.2
7.3
7.6
7.6
7.4
7.4
7.1
7.1
7.1
7.1
Temp./
°C
20
15
18
17
16
16
16
13
12
10
11
12
13
13
16
19
19
20
21
22
18
13
13
14
17
19
17
17
D.O.(a)
2.8
4.6
3.6
2.2
3.8
6.5
6.8
5.6
7.7
9.2
8.5
9.0
8.0
8.1
8.0
2.4
2.4
4.6
3.7
4.7
3.6
7.8
6.8
5.0
2.8
2.5
3.6
4.0
COD
__
615/590
--
680/635
595/555
-_
630/605
685/645
680/660
--
645/620
690/
~
715/
__
Feed
TSS
-_
42
48
--
78
40
--
62
62
46
--
50
60
--
vss
__
32
34
-.
64
'
26
~
48
40
30
38
38
^
BODg
219
259
202
262
--
140
~
120
~
168
219
198
. Effluent
COD TSS VSS
380/175 225 185
410/210 220 195
410/220 224 188
385/165 230 198
390/210 204 182
360/165 144 116
355/160 192 152
320/145 188 156
345/155 184 144
360/125 196 160
410/240 216 164
405/200 212 172
370/155 225 180
415/190 240 190
405/245 180 155
290/160 155 110
260/180 115 60
370/185 190 140
320/185 182 132
385/185 198 142
210/ 202 148
306/ 196 148
290/ 168 156
385 184 144
350 196 144
336 176 148
370/250 152 140
40/24
33/19
35/19
40/15
36/18
35/19
(a) All units mg/I.
(b) Total/filtered BOD.
(continued)
-------
AERATED STABILIZATION DATA (continued)
Basin Conditions
Day
3/1/71
2
3
4
5
6
.7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
PH
7.2
7.0
7.2
7.2
7.2
7.1
7.4
7.5
7.2
7.3
7.5
7.2
7.4
7.3
7.4
7.5
7.4
7.2
7.4
7.2
7.3
7.5
7.5
7.6
7.7
7.2
7.8
7.3
7.4
7.6
7.5
Temp.,
°C
19
21
14
12
16
15
14
17
15
18
18
20
21
22
20
20
21
20
15
15
17
19
21
20
21
19
17
19
21
18
20
D.O.(a)
7.2
3.9
3.5
5.1
6.0
4.0
5.2
6.8
6.4
1.2
5.6
4.0
3.6
3.4
2.0
2.4
1.2
3.6
2.2
7.0
3.8
1.5
3.3
1.0
4.0
2.4
9.2
2.0
2.5
2.2
1.8
COD
660/585
~
680/650
635/555
660/605
605/575
715/625
560/540
653/585
770/705
675/600
820/735
Feed
TSS
68
68
50
36
72
70
44
44
38
40
58
Effluent
VSS
36
56
38
30
~
50
50
~
38
36
28
38
~
42
BODS
188
~
208
273
312
231
264
303
~
182
246
262
-
303
COD
385/240
285/255
390/255
235/240
420/235
425/165
475/375
415/350
395/245
385/360
365/285
345/225
335/218
340/180
330/220
330/250
330/260
340/255
320/200
320/180
385/205
415/200
340/195
480/450
415/195
450/230
525/275
400/330
455/560
425/300
480/360
TSS
176
184
192
192
220
172
148
100
56
60
96
112
88
142
60
114
92
126
124
164
158
114
148
200
192
236
164
70
62
104
120
VSS
144
164
156
168
176
148
124
84
48
48
72
76
64
126
30
90
82
120
110
136
138
108
144
192
176
224
160
68
50
84
96
BOD5
35/18 (b)
34/21
34/20
72/55
61/27
54/23
97/27
104/67
90/45
100/56
72/58
70/21
90/59
93/57
98/62
108/71
79/21
93/18
75/15
60/26
80/18
72/21
54/16
115/32
76/18
82/36
1 14/47
105/50
114/58
100/49
119/32
(a) All units mg/l.
(b) Total/filtered BOD.
(continued)
-------
AERATED STABILIZATION DATA (continued)
Ol
en
Day
4/1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
PH
7.6
7.9
7.8
7.8
7.9
8.1
7.7
7.9
7.7
7.6
7.8
7.8
7.9
8.0
7.7
7.7
7.8
7.8
7.7
7.8
7'.5
7.5
7.6
7.9
7.9
7.8
7.8
7.9
7.7
8.2
Temp. ,
°C
21
18
17
18
17
14
15
16
18
20
20
20
24
21
22
21
21
21
23
23
22
22
22
21
21
22
24
24
24
24
D.O
^mi^
2.4
7.4
5.2
6.5
6.2
7.0
2.6
5.8
2.0
1.8
4.0
5.4
4.2
6.3
6.0
4.8
5.6
4.2
2.4
2.0
4.5
4.2
5.0
2.4
2.3
2.0
1.0
2.3
3.2
4.0
Feed
COD
TSS VSS BODc
850/715 76 60 366
885/780 58 46 372
730/390 52 40 319
770/765 76 58 284
950/
895/
60 40 292
72 60 303
(b) Total/filtered BOD.
705/565 60 52 162
960/780 58 46 306
1065/955 60 38 432
1140/1030 62 52
(continued)
Effluent
COD
470/360
605/200
505/275
500/280
535/340
465/265
440/295
500/230
495/250
495/270
495/260
500/260
505/270
480/230
530/
485/230
465/220
465/215
475/205
500/260
510/245
495/225
550/250
525/260
565/340
690/385
570/308
635/300
600/295
TSS
126
270
215
196
184
200
140
244
192
224
224
226
224
224
208
232
232
232
256
256
280
260
296
268
292
292
328
332
260
VSS
116
215
175
168
156
168
108
200
180
180
192
196
200
184
164
200
196
192
220
228
236
232
264
240
272
208
284
292
228
BOD5
68/26 (b)
71/24
71/27
57/22
47/25
60/13
58/24
85/30
104/33
88/30
98/28
101/28
105/28
77/29
78/25
73/28
89/19
82/28
85/17
100/35
95/23
64/22
78/21
66/22
63/25
109/33
122/21
122/30
-------
Day
5/ 1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
PH
8.1
7.2
7.9
7.9
8.0
7.8
8.2
8.2
8.3
8.6
8.1
7.7
7.8
7.9
7.8
7.8
7.9
8.1
7.7
8.0
8.3
7.7
8.0
8.6
8.5
8.1
7.6
7.4
7.7
7.5
7.6
Temp.,
°C
21
21
22
23
23
24
25
25
24
24
23
21
19
18
20
22
22
23
24
24
24
24
24
24
25
25
26
26
25
25
25
AERATED STABILIZATION DATA (continued)
Feed
Effluent
D.O.
4.9
1.8
2.8
3.5
5.0
1.3
4.7
4.9
5.3
7.0
4.1
3.0
4.1
7.8
0.2
4.9
3.9
3.3
4.3
4.6
5.3
5.9
7.7
7.6
6.2
4.6
3.7
4.0
3.6
2.6
4.3
(b) Total/filtered BOD.
COD
--
975/890
~
1223/1170
1255/1075
1070/970
895/350
-
830/675
~
945/910
940/800
925/895
905/843
TSS
70
78
68
84
90
74
66
--
52
50
-
60
vss
58
54
52
74
--
78
64
-
58
44
42
50
--
BOD5
~
532
561
Broke
Broke
429
360
--
370
371
396
545
COD
715/320
495/255
565/245
560/260
570/245
520/245
540/250
585/250
560/260
530/350
565/265
565/275
545/175
440/150
575/208
540/185
415/145
405/105
520/270
465/230
415/230
430/240
445/240
430/225
420/240
445/215
375/155
420/175
440/205
TSS
405
365
316
300
316
336
312
288
292
268
316
312
292
328
340
352
316
292
244
240
212
228
212
224
204
200
196
208
209
VSS
320
320
276
272
280
292
292
252
252
236
268
276
~
264
276
292
316
280
244
220
200
184
180
208
184
188
176
164
184
184
BOD5
180/33 (b)
165/17
172/28
174/31
178/42
170/36
168/34
Broke
~
~
124/42
105/19
116/43
105/34
89/J1
102/39
102/47
87/43
86/37
71/40
51/25
48/23
63/19
75/26
82/30
75/43
82/60
104/36
77/31
(continued)
-------
AERATED STABILIZATION DATA (continued)
pH
7.8
7.4
7.3
7.3
7.4
7.3
7.0
7.1
7.2
7.1
7.1
6.9
6.8
6.8
7.0
7.1
6.9
7.0
7.1
7.1
7.0
6.9
7.0
7.2
7.3
7.1
7.1
7.2
7.2
7.2
Temp. ,
°C
25
25
24
24
24
24
25
25
26
27
27
27
27
27
27
27
26
27
26
26
26
26
26
27
27
27
27
27
26
27
Feed
Effluent
D.O.
3.8
4.0
1.2
5.8
3.0
2.8
2.4
3.0
5.5
2.8
3.2
2.6
3.8
2.3
1.3
5.5
5.8
2.0
5.6
4.8
4.4
4.8
3.6
4.2
4.2
5.8
6.0
6.0
6.5
3.8
COD
TSS VSS BOD5
895/800 80 58 568
930/740 80 60 524
830/325 68 42 533
1100/1070 58 36 733
1068/1020 92 72 490
1210/1100 92 72 698
1180/1120 100 64 670
1110/1240 104 68 620
1390/1130 108 80 520
1160/1040 100 68 506
GOD
450/355
425/360
445/180
380/235
420/190
470/210
425/200
350/185
320/315
485/250
553/310
570/295
515/300
565/295
430/326
505/370
555/245
510/280
430/275
415/240
510/310
575/220
560/395
590/300
555/315
540/370
515/380
573/385
510/270
500/255
TSS
216
232
248
272
240
244
220
264
246
270
296
252
228
292
276
264
240
308
276
220
180
300
244
332
284
296
268
272
266
270
VSS
188
196
202
180
200
200
188
272
208
228
262
240
204
264
248
224
204
220
196
160
140
256
292
286
224
228
196
208
220
228
BOD5
85/57 (b)
88/49
--
75/35
104/31
116/35
98/34
78/32
66/27
113/37
114/58
100/55
112/49
117/36
124/53
104/36
127/40
110/32
120/78
124/30
121/42
122/59
117/56
120/40
66/31
67/22
50/17
64/22
52/21
(b) Total/filtered BOD.
-------
Ol
00
Facultative Logoon Feed
Day
10/ 7/70
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
COD (a)
265/190
340/275
295/190
280/175
240/210
280/225
240/193
168/117
168/145
255/215
265/215
330/190
200/140
105/150
195/150
195/145
320/185
290/145
255/165
205/140
345/180
295/155
TSS
57
92
68
48
55
76
40
22
24
35
35
34
26
22
49
56
52
125
82
~
VSS
46
74
54
41
48
62
31
20
14
23
25
28
16
12
34
42
38
109
56
BODg
42
57
36
28
30
27
26
23
26
51
45
45
48
36
54
67
67
67
69
58
~
TABLE 45
FACULTATIVE LAGOON DATA
No. 1 Logoon
COD TSS VSS
No. 2 Lagoon Effluent
COD
280/190
TSS
56
VSS
44
BODc
220/153 66 41
168/143 65 38
(a) Total COD/filtered COD
(b) All units are as in Table 7
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
Facultative Lagoon Feed
No. 1 Lagoon
No. 2 Lagoon Effluent
Ol
Day
ll/ 1/70
2
.3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
COD
__
430/210
445/300
420/310
390/205
335/195
410/295
390/310
395/320
360/235
350/250
295/225
345/315
670/440
745/490
555/390
495/365
360/1 17
410/270
560/~
530/380
430/395
415/295
525/390
595/375
386/288
340/330
330/296
302/260
TSS
~
~
--
156
148
188
240
126
156
142
140
106
94
96
118
118
116
130
132
106
98
94
102
47
88
vss
.»
118
102
100
124
32
122
100
60
76
66
68
80
86
90
84
86
76
74
82
80
34
62
BOD5
55
62
71
92
80
64
59
62
70
66
61
107
71
118
144
132
140
132
96
212
50/45 (d)
40/56
56/49
90/76
76/94
66/71
81/65
60/69
66/66
COD
__
~
280/210
--
330/270
330/315
310/160
~
405/360
430/320
410/296
--
TSS
~
--
:70
106
--
66
~
74
98
80
~
VSS
-
--
46
~
76
~
51
--
--
68
62
64
~
COD TSS VSS
28
15
200/160 60 36 40
270/240
30
360/260 68 38 36
335/145 53 38 64
46
394/355 78 54 62
360/278 74 58 93
74
(a) Total BCD/filtered SOD
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
facultative Lagoon Feed
No. 1 Lagoon
Day
12/ 1/70
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
COD
340/220
360/200
345/215
400/270
365/245
370/187
355/250
455/240
295/215
375/215
350/215
380/215
420/310
365/295
300/245
370/310
445/310
422/255
440/310
420/315
400/270
485/300
450/180
500/335
430/350
455/350
470/390
410/275
430/310
470/305
420/320
TSS
108
152
161
184
120
128
132
173
176
208
156
128
152
164
144
168
180
208
184
176
192
256
205
260
227
220
220
232
240
252
222
VSS
80
100
108
136
72
80
84
107
128
144
100
92
100
108
100
116
128
156
116
112
140
180
150
186
160
165
160
170
165
185
162
BOD5
76/~
81/»
64/49
127/74
90/48
78/37
72/40
87/41
83/63
78/40
37/47
27/38
42/62
53/61
93
97
123
54
56
50
55
50
53
63
59
64
65
63
59
72
COD
370/255
353/240
~
335/220
325/235
~
295/185
~
310/240
--
~
335/280
~
380/285
~
400/275
395/315
--
415/370
TSS
86
112
~
52
~
114
104
~
108
~
120
128
86
104
112
108
VSS
74
~
86
46
~
86
56
~
60
~
~
84
96
70
76
80
No. 2 Lagoon Effluent
~CO"DTSSVSS~~
327/225 84 64
320/220 84 44
295/195 104 68
68
72
78
300/190 108 56 45
290/240 88 40 66
290/205 108 64 32
350/235 156 104 36
330/280 80 60 38
325/300 76 56 31
365/315 94 60 62
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
Day
1/1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
COD
440/300
480/290
445/255
495/315
540/305
450/355
490/380
540/405
590/490
685/615
665/605
595/440
480/280
480/270
445/265
475/235
440/260
435/235
455/225
500/290
475/265
445/290
400/190
350/210
360/180
425/215
415/195
380/165
375/170
350/190
410/200
TSS
180
228
275
380
314
212
156
104
114
100
92
124
240
240
208
216
236
248
252
292
215
225
204
188
184
235
235
195
185
220
230
VSS
112
140
175
225
200
142
98
78
82
70
76
96
144
172
136
160
176
188
196
208
125
190
164
148
128
185
190
165
150
180
190
BOD
118
122
110
128
138
132
135
114/70
132/82
178/144
199/64
187/74
175/54
105
92
72
108
102
104
112
128
132
103
99
76
106
135
54
54
58
37
COD
«
365/215
415/330
385/330
510/445
--
440/360
305/280
340/285
320/305
--
~
290/260
--
230/185
--
TSS
178
194
132
66
104
~
86
124
106
116
88
VSS
126
145
--
93
-
72
44
56
84
80
--
72
--
-
64
-
-
COD
320/255
380/315
395/295
435/395
455/340
--
305/265
335/295
-
295/225
~
285/235
290/195
-
TSS
--
-
172
--
98
95
--
114
70
~
94
--
84
96
72
--
--
VSS
~
--
"
134
--
68
--
74
--
64
--
50
--
60
60
64
48
--
BOD
70
~
--
76
--
56
--
--
68
--
67
--
37
56
~
55
49
,--
~
32
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
to
Day
2/
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Facultative Logoon Feed
COD
380/175
410/210
410/220
385/165
390/210
360/165
335/160
320/145
345/155
360/125
410/240
405/200
370/155
415/190
405/245
290/160
260/180
370/185
320/185
385/185
21 0/
340/
290/
288
350
336
370/250
TSS
225
220
224
230
204
144
192
188
184
196
216
212
225
240
180
155
115
190
182
198
202
196
168
184
196
176
152
VSS
185
195
188
198
182
116
152
156
144
160
164
172
180
190
155
110
60
140
132
142
148
148
156
144
144
148
140
BOD
36
47
77
68
87
54/23
42/23
57/22
60/25
69/36
83/27
72/32
44/23
44/23
42/26
37/23
31/26
56/28
69/45
40/24
33/19
35/19
40/15
36/18
35/19
No. 1 Lagoon No. 2 Logoon Effluent-
COD TSS VSS COD TSS VSS BOD
246/165 88 76 200/165 60 48 31
290/200 102 84 250/170 88 66 42
265/170 96 78 255/185 78 58 32
240/160 90 70 210/160 72 60 32
240/185 84 68 210/195 76 48 28/22 (a)
230/195 74 46 225/185 68 42 26/26
225/200 42 28 210/195 46 30 34/27
210/ 46 31 290/
76 52 162
34 23 32/16
42 26
327/177 70 64 210/170 52 44
(a) Total/filtered BOD5.
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
Facultative Lagoon Feed No. 1 Lagoon _ No. 2 Lagoon Effluent
Day
3/
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
COD
385/240
285/255
390/255
285/240
425/235
425/165
475/375
415/350
395/245
365/360
365/285
345/225
335/210
340/180
330/220
330/250
330/260
340/255
320/200
320/180
385/205
415/200
340/195
480/450
115/195
450/230
525/275
400/330
455/360
420/300
480/360
TSS
176
184
192
i92
200
172
148
100
56
60
96
112
88
142
60
114
92
126
124
164
158
114
148
200
192
236
164
70
62
104
120
VSS
144
164
156
168
176
140
124
84
48
48
72
76
64
126
30
90
82
120
110
136
138
108
144
192
176
224
160
68
. . 50
84
96
BOD
35/18
34/21
34/20
72/55
61/27
54/23
97/27
104/67
90/45
100/56
78/58
70/21
90/59
93/57
98/62
108/71
79/21
93/18
75/15
60/26
80/18
72/21
54/16
1 15/32
76/18
82/36
114/47
105/50
" 1 14/48
100/49
119/32
COD
275/245
315/240
380/280
340/245
290/180
385/260
245/215
300/210
--
280/200
--
345/270
TSS
--
84
90
80
42
-
50
46
52
88
--
88
62
VSS
72
76
~
68
--
28
34
44
44
86
86
48
COD
ISS VSS
BOD
245/205 60 30 31/15
260/190 68 54 26/14
335/225 68 60 42/32
310/230 36 30 67/40
245/210 40 22 41/~
243/230 34 32 42/17
260/215 34 28 36/34
265/210 48 46 36/20
265/185 50 48 57/20
280/265 44 34 65/25
-------
FACULTATIVE LAGOON DATA (continued)
Facultative Lagoon Feed
No. 1 Lagoon
No. 2 Lagoon Effluent
Day
4/1/71
2
3
4
5
6
7
8
9
ib
it
12
13
14
15
16
17
18
19
20'
21
22
23
24
25
26
27
28
29
30
COD
470/360
605/290
505/275
500/280
535/340
465/265
440/295
500/230
495/250
495/270
495/260
500/260
505/270
480/230
530/
485/230
465/220
465/215
475/205
500/260
510/245
495/225
550/250
525/260
565/340
690/385
570/308
635/300
600/295
TSS
126
270
215
196
184
200
140
244
192
224
224
224
224
224
208
232
232
232
256
256
280
260
296
268
292
292
328
332
260
vss
116
215
175
168
156
168
108
200
180
180
192
196
200
184
164
200
196
192
220
228
236
232
264
240
.272
208
284
292
228
BOD5
68/26
71/24
71/27
57/22
47/25
60/13
58/24
85/30
104/33
88/30
98/28
101/28
105/28
77/29
78/25
73/28
89/19
82/28
85/17
100/35
95/23
64/22
78/21
66/22
63/25
109/33
122/21
122/30
~
COD
415/355
~
465/380
~
300/225
520/270
325/240
~
~
355/210
395/265
--
465/350
~
480/325
-
TSS
72
~
66
~
62
94
136
128
~
140
122
140
176
~
vss
52
56
48
82
104
120
128
106
128
152
COD
315/280
365/355
~
280/240
310/265
335/280
375/290
300/215
330/250
~
370/355
420/295
~
TSS
60
36
46
62
92
88
116
88
108
136
VSS
38
~
30
~
32
28
72
80
92
--
80
96
120
~
BOD5
.64/30
~
45/22
35/18
39/20
41/20
40/19
43/21
27/10
94/19
65/12
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
Facultative Lagoon Feed
No. 1 Lagoon
Day
5/1/71
2
3!
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
COD -
715/320
495/255
565/245
560/260
570/245
520/245
540/250
585/250
560/260
530/350
565/265
565/275
545/175
440/150
575/205
540/185
415/145
405/105
520/270
465/230
415/230
430/240
445/240
430/225
420/240
445/215
375/155
420/175
490/205
TSS
405
365
316
300
316
336
312
288
292
268
316
312
292
328
340
352
316
292
244
240
212
228
212
224
204
200
196
208
209
VSS
320
320
276
272
280
292
292
252
252
236
268
276
264
276
292
316
280
~
244
220
200
184
180
208
184
188
176
164
184
184
BOD5
180/33
165/17
172/28
174/31
178/42
170^36.
168/34
Broke
t24/42
105/19
116/43
105/34
69/31
102/39
102/47
87/43
86/37
71/40
51/25
48/23
63/19
75/26
82/30
75/43
82/60
104/36
77/31
COD
425/320
--
--
435/320
465/280
420/315
~
380/205
385/205
360/145
~
-
395/260
355/290
--
~
320/305
TSS
-
144
--
160
--
148
136
--
136
--
160
200
--
~
158
--
120
~
-
94
~
VSS
~
132
140
--
144
--
124
~
128
144
~
172
-
~
136
--
96
--
--
80
No. 2 Lagoon Effluent
COD
360/270
405/310
410/296
410/295
310/200
320/200
275/145
345/245
TSS
124
124
124
124
108
112
148
128
VSS
108
112
112
100
104
104
128
112
BOD5
51/19
52/21
63/37
61/34
57/37
61/34
51/38
38/26
320/255 108 84 52/22
315/260 80 70 51/46
(continued)
-------
FACULTATIVE LAGOON DATA (continued)
FocultoMve Lagoon Feed
No. 1 Lagoon
Day
6/1/71
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
COD
450/355
425/360
445/180
380/235
420/190
470/210
425/200
380/185
320/315
485/250
553/310
570/275
515/300
565/295
430/320
505/370
555/245
510/280
460/275
415/240
5 10/3 TO
575/220
560/395
590/300
555/315
540/370
615/380
570/305
510/270
500/255
TSS
2ll
232
248
272
240
244
220
264
246
270
296
252
228
292
276
264
240
308
276
220
180
300
244
332
284
296
268
272
266
270
VSS
188
196
202
180
200
200
188
212
208
228
262
240
204
264
248
224
204
220
196
160
140
256
292
286
224
228
196
208
220
228
BOD5
85/57
88/49
75/35
104/31
116/35
98/34
78/32
66/27
113/37
1 14/58
100/55
112/49
117/36
124/53
104/36
127/40
110/32
102/28
104/30
121/42
122/39
117/36
120/40
66/31
67/22
50/17
64/22
52/21
COD
245/240
300/285
355/220
330/230
425/300
370/340
--
395/350
--
~
400/340
--
435/350
-
420/370
-
--
TSS
82~
72
92
102
164
100
-
96
104
104
~
112
--
VSS
74
56
72
84
132
88
~
64
88
92
'
80
No. 2 Lagoon Effluent
COD TSSVSSBOD5
290/235 86~ 76~ 65/38
330/260 100 88
355/-- 76 48
50/25
305/240 88 72 48/28
295/245 76 58 57/31
330/270 128 112 35/15
380/270 56 44 61/36
305/295 72 56 46/21
290/275 116 100 42/28
325/285 68 44 43/23
34/15
-------
I. 4a.m. 10/1/70
Parameter
ORP, mv
Temp., °C
CODT/CODF/ mg/l
VA, mg/l as HAc
TOC, mg/l (a)
S=, mg/l
SO4, mg/l
Parameter
pH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4, mg/l
TABLE 46
ANAEROBIC BASIN PROFILES
Deep Lagoon
Inlet
Outlet
Surface
3ft
7.4 7.3
-340 -360
26 26
1060/705 905/695
250 250
200 215
59 60
204 188
6ft
Sludge
7.5 7.9
-350 -320
26 26
895/605 910/540
215 205
195 150
69 76
120 84
Surface 3 ft
6ft
Sludge
7.4 7.4 7.4 8.0
-340 -370 -370 -390
26 26 26 26
755/735 760/815 750/670 61.0/550
215 215 130 180
145 135 180 100
47 55 45 73
204 208 208 100
Shallow Lagoon
Inlet
Surface 3 ft
7.7 7.7
-320 -330
25 25
595/535 585/510
215 215
90 105
39 45
140 92
Sludge
8.0
-370
25
585/460
170
110
33
148
Outlet
Surface 3 ft
7.7 7.7
-35 -360
25 25
630/455 625/475
215 205
160 145
35 32
156 140
Sludge
8.1
-380
25
555/540
180
75
43
188
(a) All samples for total carbon determinations are filtered and
nitrogen purged at low pH
-------
CD
I. 4p.m. 10/1/70
Parameter
PH
ORP, mv
Temp., °C
CODj/CODp, ma/I
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
S04, mg/l
Parameter
ORP, mv
Temp., °C
CODT/CODF/ mg/l
VA, mg/l as HAc
TOC, mg/l
S-, mg/l
SO4, mg/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Surface
8.0
-320
31
795/695
270
230
50
256
Inlet
3ft
7.7
-350
30
825/710
265
235
54
258
Outlet
6 ft
7.7
-360
30
Sludge
8.0
-380
30
925/685 1680/595
240
220
70
166
210
200
84
66
Surface
8.0
-320
31
3 ft
7.7
-340
30
755/575 680/610
210
200
51
254
215
220
53
204
6 ft
7.7
-350
30
755/505
140
180
70
166
Sludge
8.0
-380
30
455/430
190
150
84
68
Shallow Lagoon
Surface
8.0
-320
31
Inlet
3 ft
7.8
-350
31
Outlet
570/495 565/515
220
125
22
180
220
140
26
182
Sludge
7.8
-390
30
525/430
180
110
64
68
Surface
8.0
-330
31
590/495
215
140
31
190
3 ft
8.0
-370
31
565/515
205
125
46
164
Sludge
7.9
-350
30
525/430
180
130
37
166
-------
ANAEROBIC BASIN PROFILES (continued)
>o
II. 4a.m. 10/8/70
Parameter
pH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO., mg/l
Parameter
ORP, mv
Temp., °C
COD-r/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
Deep Lagoon
Inlet
Outlet
3ft
Surface
7.3 7.3
-340 -350
29 29
735/640 730/655
265 250
245 200
49 51
270 265
6 ft Sludge
3 ft
6 ft Sludge
7.2 7.9
-360 -400
29 28
720/620 2630/570
265 145
230 190
48 102
265 20
Shallow Lagoon
Surface
7.3 7.3 7.2 8.0
-350 -360 -360 -370
29 29 29 29
710/710 735/650 720/720 2600/830
275 265 265 170
290 240 240 165
38 50 51 112
290 300 290 40
SO,
m
g/l
Surface
Inlet
3ft
7.7 7.7
-350 -360
27.5 27.5
570/510 565/530
215 190
140 180
37 38
210 210
Sludge
7.6
-370
27.5
1780/470
190
180
38
215
Surface
Outlet
3 ft
7.7 7.7
-250 -240
27 27.5
575/570 590/575
190 205
180 150
34 38
240 195
Sludge
7.6
-220
27.5
930/720
190
190
42
195
-------
ANAEROBIC BASIN PROFILES (continued)
V\. 4:30 p.m. on 2/17/71
Parameter
pH
ORP, mv
Temp., °C
CODT/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO,
'4'
m
Parameter
pH
ORP, my
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4, mg/l
Deep Lagoon
Surface
7.0
-300
24
685/580
216
205
15
380
Surface
7.0
-280
23
Inlet
3ft
6.8
-305
24
690/585
240
205
20
375
Inlet
3ft
7.0
-280
23
Outlet
6ft
6.7
-300
24
700/595
264
210
23
360
635/540 620/505
192
170
5
380
204
165
5
410
Sludge
6.8
-300
24
655/530
264
200
47
290
Shallow Lagoon
Sludge
7.0
-300
23
615/440
240
160
29
305
Surface
6.9
-300
24
3 ft
6.9
-310
24
6ft
6.9
-310
24
635/530 675/565 630/560
264
195
19
375
Surface
7.1
-290
23
278
180
18
380
Outlet
3ft
7.1
-300
23
278
180
16
370
615/380 615/400
228
160
5
380
240
165
5
385
Sludge
6.9
-290
23
670/550
264
185
38
300
Sludge
7.1
-310
23
640/420
264
165
21
290
-------
-111. 4a.m. on 10/29/70
Parameter
PH
ORP, mv
Temp., °C
GOOT/CODF/ mg/l
VA, mg/l as HAc
TOC, mg/l
S", mg/l
SO
4'
ig/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Inlet
Surface 3 ft
7.4 7.4
-340 -340
24 24
800/520 820/590
228 228
175 190
68 70
80 82
6 ft Sludge
7.4 7.4
-340 -340
24 24
800/605 790/585
240 240
190 175
69 70
80 80
Outlet
Surface 3 ft
6ft
Sludge
7.4 7.4 7.4 7.5
-340 -350 -350 -340
24 25 24 24
785/665 775/605 780/605 780/615
228 216 228 228
195 185 195 195
68 68 70 75
65 70 72 70
Shallow Lagoon
Parameter
pH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
SB, mg/l
SO,
ru-
Surface
7.4
-320
24
Inlet
3ft
7.4
-340
24
615/520 615/520
120
210
46
105
132
210
43
100
Sludge
7.4
-340
24
620/500
144
195
43
103
Surface
7.4
-340
23
695/525
120
180
40
84
Outlet
3ft
7.4
-340
24
635/570
180
195
42
75
Sludge
7.4
-340
24
680/495
180
180
39
78
-------
ANAEROBIC BASIN PROFILES (continued)
II. 4p.m. on 10/8/70
Parameter
KJ
pH
ORP, my
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO, mg/l
Deep Lagoon
Inlet
3ft
Surface
6.9 6.9
-330 -320
27.5 28
710/580 740/560
260 250
210 215
46 48
245 255
6 ft Sludge
6.9 7.7
-350 -370
28 28
740/615 1805/440
260 145
210 180
44 109
260 80
Outlet
6 ft Sludge
Surface 3 ft
6.9 6.9 6.9 7.7
-350 -300 -350 -365
28 28 28 27.5
680/595 725/585 715/605 1585/475
270 260 260 180
150 155 155 105
33 31 34 103
290 285 285 20
Shallow Lagoon
Parameter
PH
ORP, mv
Temp, C
CODT/CODp/ mg/l
VAf mg/l as HAc
TOC, mg/l
S=/ mg/l
SO4, mg/l
Inlet
Surface 3 ft
7.3 7.3
-340 -350
27.5 28
650/475 615/495
210 195
185 180
30 26
205 210
Sludge
7.4
-365
28
935/530
195
140
37
180
Outlet
Surface 3 ft
7.3 7.3
-320 -330
27.5 28
535/405 530/425
200 205
130 130
33 32
195 200
Sludge
7.3
-340
28
660/450
195
150
40
165
-------
VI
CO
III. 3 p.m. on 10/29/70
Parameter
pH
ORP, mv
Temp., dC
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S-, mg/l
SO4/ mg/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Inlet
3ft
Surface
7.4 7.4
-410 -420
25 25
745/510 770/585
150 165
180 185
41 65
85 75
6ft
Sludge
7.2 7.2
-420 -420
25 24
775/545 750/510
190 220
185 180
67 76
80 80
Outlet
3ft
6 ft Sludge
Surface
7.4 7.3 7.3 7.3
-400 -420 -410 -420
25 25 25 24
740/525 755/530 770/545 715/510
160 170 185 220
175 180 185 170
66 68 69 73
80 78 72 65
Shallow Lagoon
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S-, mg/l
$04, mg/l
Surface
7.6
-370
23
Inlet
3ft
7.6
-400
22
435/310 460/325
145
155
47
95
145
165
50
90
Sludge
7.4
-410
21
495/335
155
170
50
95
Surface
7.6
-380
23
Outlet
3ft
7.6
-420
23
455/325 475/340
155
155
39
88
140
155
41
85
Sludge
7.5
-420
22
490/345
160
160
44
80
-------
ANAEROBIC BASIN PROFILES (continued)
IV. 4a.m. on 11/18/70
Parameter
pH
ORP, mv
Temp., °C
CODj/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
$04, mg/l
Deep Lagoon
Surface
7.0
-330
20
890/775
218
235
40
170
Inlet
3 ft
7.0
-350
21
920/760
276
235
42
180
Outlet
6ft
7.0
-355
21
910/725
276
220
38
180
Sludge
7.15
-365
21
820/695
240
195
49
105
Surface
7.0
-340
19
900/765
264
220
35
160
3 ft
6.9
-350
21
890/760
240
210
35
160
6 ft
7.0
-350
21
880/730
264
210
38
160
Sludge
7.15
-360
21
810/715
240
135
50
80
Shallow Lagoon
Parameter
PH
ORP, mv
Temp., °C
CODy/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=7 mg/l
$04, mg/l
Surface
7.0
-350
17
790/670
205
200
30
185
Inlet
3ft
7.1
-360
17
790/660
192
200
31
185
Sludge
7.3
-390
18
760/585
192
185
45
125
Surface
7.1
-350
18
Outlet
3ft
7.1
-360
18
835/700 805/700
205
210
29
165
205
190
31
160
Sludge
7.3
-380
17
760/600
205
200
42
110
-------
XJ
Oi
IV. 4p.m. on 11/18/70
Parameter
pH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
5=, mg/l
SO., mg/l
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
SB, mg/l
SO4, mg/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Inlet
Outlet
Surface 3 ft
7.0 7.0
-350 -355
23 23
740/645 845/620
224 288
225 235
43 43
190 165
6 ft Sludge
7.1 7.0
-360 -370
22 21
810/655 735/565
288 256
220 205
45 50
165 100
Shallow Lagoon
Surface
7.0
-355
23
855/645
260
240
38
165
3ft
6ft
Sludge
7.0 7.1 7.3
-365 -370 -380
23 22 21
835/665 840/645 765/560
276 265 252
230 235 220
38 45 50
170 170 100
Inlet
Surface 3 ft
7.2 7.2
-330 -345
20 20.5
745/495 740/515
180 204
195 200
27 31
110 190
Sludge
7.2
-355
19
725/445
192
190
47
110
Outlet
Surface 3 ft
7.2 7.2
-340 -350
21 20
755/520 750/530
228 228
205 210
25 36
110 150
Sludge
7.2
-355
19
730/465
204
200
45
115
-------
ANAEROBIC BASIN PROFILES (continued)
Vj
V. 4a.m. on 1/13/71
Parameter
pH
ORP, mv
Temp., °C
CODT/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
so,
m
g/l
Parameter
ORP, mv
Temp., °C
CODT/CODF/ mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4, mg/l
Deep Lagoon
Surface
6.9
-265
21
775/735
240
245
17
230
Surface
6.8
-205
20
Inlet
3ft
6.9
-230
21
785/735
240
245
24
215
Inlet
3ft
6.7
-220
19
Outlet
6 ft
6.8
-230
16
785/720
216
250
21
230
Sludge
7.2
-250
15
725/645
216
245
42
96
Shallow Lagoon
Surface
6.9
-190
21
780/760
240
220
17
245
3ft
6.9
-230
21
790/765
240
210
22
245
6ft
6.8
-255
16.5
785/710
228
205
23
225
Sludge
7.2
-285
15
725/630
192
225
42
45
Outlet
755/700 745/700
252
210
Nil
300
240
225
5
310
Sludge
7.1
-260
14
680/590
228
220
10
164
Surface
6.9
-210
20
760/700
240
180
Nil
300
3ft
6.8
-215
19
755/700
228
250
5
410
Sludge
7.1
-255
14
675/600
216
245
5
145
-------
V. 4p.m. on 1/13/71
Parameter
pH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
$04, mg/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Inlet
3ft
Surface
6.9 6.9
-275 -275
22.5 22
780/605 765/600
228 216
225 220
21 30
230 220
6ft
Sludge
6.9 7.2
-285 -305
16 15
775/675 680/590
240 228
220 205
33 67
245 75
Outlet
3ft
6ft
Sludge
Surface
7.0 6.9 7.0 7.2
-240 -255 -275 -285
22 21.5 16 15
785/610 765/605 740/535 665/515
228 240 228 216
225 220 215 200
31 31 18 40
225 210 220 100
Shallow Lagoon
Parameter
PH
ORP, mv
Temp., °C
CODT/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4, mg/l
Inlet
Surface 3 ft
6.9 6.9
-245 -255
22 19
700/515 600/550
240 228
190 175
18 5
260 300
Sludge
7.0
-280
14
645/470
216
165
11
290
Outlet
Surface 3 ft
6.9 6.9
-270 -260
22 20
690/500 695/540
228 228
185 190
5 15
280 280
Sludge
7.1
-265
15
650/455
216
180
17
210
-------
ANAEROBIC BASIN PROFILES (continued)
VI
CO
V\. 4:30 a.m. on 2/17/71
Parameter
PH
ORP, mv
Temp., °C
CODy/CODp, mg/l
Vk, mg/l as HAc
TOC, mg/l
S=, mg/l
SO,
m
g/l
Parameter
PH
ORP, rr\v
Temp., °C
CODT/CODF/ mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO,
m
g/l
Deep Lagoon
Surface
6.8
-310
22
740/645
230
180
19
335
Surface
7.0
-320
20
Inlet
3 ft
6.8
-300
21
740/680
230
170
17
355
Inlet
3ft
6.9
-300
21
Outlet
6 ft
6.8
-340
20
Sludge
6.8
-340
20
725/655 715/630
240
160
19
350
192
195
32
275
Shallow Lagoon
Surface
6.8
-310
21
740/670
230
170
19
335
3ft
6.8
-320
21
740/645
278
210
16
360
6ft
6.8
-330
20
Sludge
6.9
-340
19
705/645 695/585
336
200
15
350
264
205
31
280
Outlet
645/630 680/630
288
185
5
370
264
205
5
370
Sludge
6.9
-280
21
655/630
230
210
5
365
Surface
7.0
-280
21
3 ft
7.0
-300
21
690/600 665/610
216
195
5
360
230
195
8
325
Sludge
7.0
-320
20
690/530
264
180
19
330
-------
-O
VII. 4:30 a.m. on 3/17/71
Parameter
pH
ORP, my
Temp., °C
CODT/CODp, mg/l
VA, mg/l as HAc
TOG, mg/l
S=, mg/l
SO,
m
g/i
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Inlet
Surface
6.8
3ft
6.8
-340 -350
24 25
610/495 672/495
348 276
165 170
42 40
375 360
6ft
Sludge
6.8 6.7
-350 -350
25 25
610/520 595/390
312 324
160 160
43 42
380 ~ 355
Outlet
3 ft
6ft Sludge
Surface
6.8 6.8 6.8 7.0
-330 -350 -350 -370
24 25 25 24
640/465 670/515 620/545 740/565
288 264 276 276
170 175 170 190
42 ~ 41 39 39
375 375 375 365
Shallow Lagoon
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S-r mg/l
SO4/ mg/l
Surface
7.0
-300
22
Inlet
3ft
7.0
-320
23
605/445 555/430
264
155
35
345
264
145
35
340
Sludge
6.9
-340
22.5
555/360
276
150
35
330
Surface
7.0
-330
22
550/415
336
160
33
315
Outlet
3ft
7.0
-345
23
575/395
312
160
28
350
Sludge
7.0
-350
23
390/420
384
165
26
355
-------
VII. 4:00 p.m. on 3/17/71
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF/ mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4/ mg/l
Parameter
pH
ORP, mv
Temp., °C
CODT/CODp, mg/l
VA, mg/l as HAc
TOC, rng/1
S=, mg/l
SO4, mg/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Surface
7.1
-340
25
Inlet
3ft
7.1
-360
24
600/545 630/560
228
155
36
375
228
160
38
365
Outlet
6ft
7.0
-360
23
SI udge
7.2
-380
23
655/570 590/500
252
160
40
355
156
165
84
185
Surface
7.0
-340
24
620/545
240
160
33
365
3ft
6.9
-350
23
610/570
252
165
38
365
6ft
6.8
-370
23
Sludge
6.9
-370
22
655/530 545/450
276
165
40
360
276
155
83
190
Shallow Lagoon
Surface
7.3
-320
24
Inlet
3ft
7.2
-360
23
580/440 520/415
228
155
30
345
252
145
29
335
Sludge
7.1
-360
22
585/445
312
155
33
325
Surface
7.2
-320
23
Outlet
3ft
7.2
-350
23
505/420 505/415
300
145
33
325
336
145
32
330
Sludge
7.1
-370
23
555/445
324
155
29
330
-------
00
VIII. 5:30 a.m. on 4/26/71
Parameter
pH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
$04, mg/l
ANAEROBIC BASIN PROFILES (continued)
Deep Lagoon
Inlet
Outlet
3ft
Surface
6.9 6.8
-360 -350
26 26
1140/935 1170/880
360 360
119
100
6ft Sludge
7.0 6.7
-390 -390
26 25
1190/925 1290/760
372 336
Analyzers were not working
111 115 130 111
105 65 40 90
Surface 3 ft 6ft Sludge
6.8 6.9 6.9 6.9
-290 -360 -360 -380
26 26 25 24.5
1120/950 1090/925 1175/835 «
384 372 360
116
85
114
75
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO,
m
g/l
Shallow Lagoon
Surface
7.0
-320
25
Inlet
3 ft
7.0
-340
25
915/830 830/820
418
56
175
480
Ana lyze rs
51
170
Sludge
6.9
-350
25
1170/775
420
were not wo
55
155
Surface
6.9
-320
25
Outlet
3ft
7.0
-350
25
920/790 965/785
456
rking
49
165
480
48
165
Sludge
7.0
-360
25
1050/940
420
51
190
-------
ANAEROBIC BASIf4 PROFILES (continued)
CD
ro
VIII. 4:00 p.m. on 4/26/71
Parameter
PH
ORP, mv
Temp., °C
CODy/CODp, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4, mg/l
Parameter
PH
ORP, mv
Temp., °C
CODT/CODF, mg/l
VA, mg/l as HAc
TOC, mg/l
S=, mg/l
SO4, mg/l
Deep Lagoon
Surface
7.4
-380
27
1110/840
312
83
120
Inlet
3ft
7.2
-390
25
1150/910
336
Analyze
102
110
Outlet
6ft
7.1
<390
24
1150/840
312
rs were
107
55
Sludge
7.0
-400
23
885/680
240
not work
138
50
Surface
7.3
-380
27
3ft
7.0
-380
25
6ft
7.1
-390
24
1000/950 1080/990 1060/955
384
ing
105
105
324
117
95
348
148
25
Sludge
6.9
-390
23
885/730
288
148
25
Shallow Lagoon
Surface
7.4
-320
27
870/820
384
47
165
Inlet
3ft
7.3
-340
25
845/740
360
Analyze
70
150
Outlet
rs were
Sludge
7.3
-370
24
845/770
418
not work
72
135
Surface
7.3
-360
27
3ft
7.3
-370
24
910/695 865/845
348
ing
54
195
360
65
170
Sludge
7.3
-380
23
915/645
360
72
150
-------
APPENDIX II
EXPERIMENTAL MET 1ODS AND APPARATUS
It Analytical Methods
The analytical methods used during the bench-, semi-pilot, and pilot-scale
studies are:
A. Alkalinity - Alkalinity was determined to the methyl orange endpoint as given
in Standard Methods (21).
B. Anaerobic Gas Composition - Gas composition was measured using a Perkin
Elmer Model 154 Vapor Fractionator* (gas chromatograph).
C. Biochemical Oxygen Demand (BOD) - All five-day BOD determinations were
performed in accordance with Standard Methods (21). In many cases analyses were
made on both filtered and unfiltered samples. Filtered BOD tests were made on
samples after filtration through quantitative filterpaper (Whatman No. 42 or equiva-
lent).
Twenty-day BOD determinations were based in part on a technique used at Office
of Water Programs-Wheel ing and in part on techniques developed by Union Carbide.
Based on advice of the EPA the dilution water forall long-term BOD determinations
was aerated to 15 to 20 mg/l dissolved oxygen with pure oxygen. Contained oxygen
was monitored at frequent intervals (3, 5, 7, 10, 15 and 20 days) using a polaro-
graphic technique. Acclimated, petrochemical seed was used in all BOD deter-
minations.
During initial BOD2Q determinations problems were experienced with a high oxygen
uptake after a period of 10 to 15 days. As the BOD within the samples was usually
exerted prior to this.time the increase in uptake by the blank resulted in a decrease
in calculated BOD. In cases where the BOD was noted to decrease after 10 days'
incubation the ultimate BOD was taken to be the maximum BOD observed within the
20-day test. The problem was ultimately avoided through a change in dilution water
source and use of larger sample sizes for analysis.
* Perkin Elmer, Norwalk, Connecticut
183
-------
D. Chemical Oxygen Demand (COD - COD determinations were made on both
unfiltered and filtered samples by the dichromate-reflux method as presented in^
Standard Methods (21). Special care was necessary during the analysis to contain
the oxygen-demanding dissolved sulfides in the anaerobic samples. The sample was
added to the reflux flask after all reagents were present so that the sulfides were
oxidized by the dichromate before being evolved to the atmosphere in the acid
environment.
E. Dissolved Oxygen (DO) - DO was measured using a polarographic probe*
or by the alkaline-azide modification of the Winkler titration as presented in
Standard Methods(21). The polarographic probe was calibrated using the Winkler
Technique,
F. Gas-Liquid Chromatography - Specific chemical analyses were made by direct
liquid injection using a Varian Aerograph Model 1200** chromatograph and a
10-foot Porapak Q column.
G, Nitrates - Evaluation of available methods on anaerobic-lagoon samples indicat-
ed the Brucine Method as outlined in Standard Methods (21) could be used. Other
methods failed due to interferences.
H. Oxidation Reduction Potential (ORP) - ORP was measured using an Analytical
Measurement Model 707M Redox-pH meter*** and a platinum probe.
I. pH - pH was measured using the Glass Electrode Method specified in Standard
Methods (21).
J. Phosphate - An evaluation was made of the available phosphate methods to
determine which was applicable to the anaerobic-lagoon system. The molybdenum-
blue methods as outlined in Standard Methods (21) and the FWPCA Manual (22) were
found to be unsuitable for the samples taken from the anaerobic lagoons. It was known
that the presence of sulfide ions would interfere with the molybdenum-blue methods.
However, after employing several sulfide-removal techniques (sparging under acidic
conditions, mild oxidation, and precipitation) problems still existed with the above
methods. Applying these methods after the removal of the sulfide led to the formation
of a yellow solution upon the addition of the reducing agent. The yellow color could
***
Yellow Springs Instrument Company, Model No. 51 or 54, Yellow Springs, Ohio
Varian Aerograph, Walnut Creek, California
Analytical Measurements, Inc., Chatham, New Jersey
184
-------
not be correlated to the phosphate content, and the blue complex would not form on
standing for periods up to two hours. All the above methods employ sulfuric acid.
Substituting hydrochloric acid for sulfuric acid eliminated the yellow-color formation
and the blue complex formed as would be expected. Because the methods employing
sulfuric acid performed well on synthetic samples but not well on actual samples, it
might be concluded that the sulfuric acid reacted with some component in the samples
under reducing conditions, whereas hydrochloric acid did not. Due to time con-
sideration, the exact nature of this interference was not established.
Sparging with nitrogen under acidic conditions was found to remove the sulfide
content to a satisfactory level to allow the application of the following molybdenum-
blue method utilizing hydrochloric acid for the determination of soluble orthophosphate,
A hydrolyzable phosphate was subjected to the soluble-orthophosphate method and
found not to interfere with the orthophosphate analysis. After it was established that
the hydrochloric acid version worked satisfactorily on synthetic samples, the method
was applied to representative lagoon samples and spiked lagoon samples. The spikes
were recovered and the orthophosphate content was found to check within approxi-
mately 2 milligrams per liter in the 0 to 50 milligrams per liter range.
A technique to permit the determination of all phosphorous-containing components
was sought with no immediate success. With all the digestion techniques tried, part
of the orthophosphate content known to be present was lost before the organic matter
was completely digested. Because the phosphate employed by the bacteria is
generally converted to a hydrolyzable phosphate, the total phosphorous method was
abandoned for a method which would yield total-ortho-plus-hydrolyzable phosphate.
The total-ortho-plus-hydrolyzable-phosphate method used was checked on known
synthetic and representative samples and found to reproduce results within 5 milli-
grams per liter at the 50 to 100 milligrams per liter range (expected range on lagoon-
effluent samples). It should be noted that the soluble-orthophosphate method utilizes
a filtered sample, whereas the rbtal-ortho-plus-hydrolyzable-phosphate method
utilizes an unfiltered sample.
Preservation of samples was checked employing two different preserving agents:
mercuric chloride and chloroform. No detectable difference was noted with respect
to choice of preserving agent. However, because samples must either be sparged
free of sulfide prior to the addition of mercuric chloride or have excess mercuric
chloride added to remove the sulfide in a mercuric sulfide precipitate, it is
recommended that the samples be preserved with chloroform (5 milliliters per liter).
185
-------
1. Soluble Orthophosphate
a. Reagents
i) Sodium Molybdate Reagent: Dissolve 100 grams of sodium
molybdate dihydrate (NaMoO4«2H2O) in distilled water
and dilute to one liter.
ii) Ascorbic Acid Reagent: Dissolve 10 grams of ascorbic acid
in distilled water and dilute to 100 milliliters.
iii) Hydrochloric Acid Solution; Add 100 milliliters of concen-
trated c.p. hydrochloric acid to 500 milliliters of distilled
water, cool, and dilute to one liter. Be careful.
iv) Phenolphthalein Indicator; Dissolve 0.5 gram of phenol-
phthalein disodium salt in distilled water and dilute to one
liter.
v) Potassium Hydroxide Solution; Dissolve 6.5 grams of
potassium hydroxide in distilled water and dilute to 100
I I I i
milliliters.
b. Procedure
i) Filter 60 milliliters of a well-mixed sample through Whatman
No. 4 paper, employing gravity filtration.
ii) Pipet 50 milliliters of the filtrate, or a suitable dilution,
into a 100-mi Hi liter, glass-stoppered graduated cylinder.
The 50 milliliters of filtrate should not contain more than
0.6 milligram of phosphate (PO^.). Most samples will
probably require a 1 to 10 dilution.
iii) Add four drops of phenolphthalein indicator and adjust the
pH to the phenolphthalein endpoint with the hydrochloric
acid or potassium hydroxide solution.
iv) Pipet 50 milliliters of distilled water into a 100-milliliter
graduate and adjust the pH to the phenolphthalein endpoint.
This will serve as a blank.
186
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v) Using a pipet introduce 10 milliliters of the diluted hydro-
chloric acid solution dropwise into the sample graduate
while sparging with nitrogen. Continue the nitrogen sparge
for 10 minutes after the addition of hydrochloric acid. Add
10 milliliters of the hydrochloric acid solution to the blank;
the nitrogen sparge is not necessary for the blank.
vi) Using a pipet, transfer 10 milliliters of sodium molybdate
reagent to both sample and blank graduates and invert
several times.
vii) Pi pet one milliliter of ascorbic acid solution into the sample
and blank graduates and invert several times.
viii) Dilute both sample and blank to 100 milliliters, invert
several times, and allow to stand for 10 minutes, timed from
the addition of ascorbic acid.
ix) Employing one-centimeter cells, measure the absorbance at
800 millimicrons with a Beckman* Model Bor equivalent
instrument. Use the blank to zero the instrument. From a
previously prepared calibration curve read the concentration
of soluble orthophosphate in milligrams per liter.
2. Total Hydrolyzable and Orthophosphate
a. Reagents
i) Concentrated Potassium Hydroxide Solution: Dissolve 65
grams of potassium hydroxide in distilled water and dilute
to 100 milliliters . This solution must be stored in a
polyethylene bottle.
ii) Concentrated Hydrochloric Acid: Concentrated c.p.
hydrochloric acid (approximately 11.6N).
iii) Remaining Reagents: The same as for soluble-orthophosphate
method.
* Beckman Instruments, Inc., Fullerton, California.
-------
b. Procedure
I) Via a graduated cylinder, add 50 milliliters of a well-mixed
sample, or suitable dilution to a 250-milliliter polyethylene
bottle. The 50 milliliters of sample should not contain more
than 0.6 milligram of phosphate (PO4). Most samples will
probably require a 1 to 20 dilution.
ii) Add 50 milliliters of distilled water to a 250-milliliter
polyethylene bottle for use as a blank.
iii) Into both sample and blank pipet 10 milliliters of dilute
hydrochloric acid dropwise while sparging with nitrogen.
Continue the nitrogen sparge for 10 minutes after the
addition of the acid. Sparging of the blank is not necessary.
iv) Into both sample and blank pipet 2 milliliters of concentrated
hydrochloric acid and heat in a steam bath for 30 minutes.
v) Cool and filter through Whatman No. 4 paper into a 100-
milliliter glass-stoppered graduate, washing the poly-
ethylene bottle and filter paper with 5 milliliters of distilled
water.
vi) Sparge again with nitrogen for an additional period of five
minutes.
vii) Add four drops of phenolphthalein indicator and neutralize
to the phenolphthalein endpoint employing the concentrated
potassium hydroxide solution.
viii) Pipet 10 milliliters of the dilute hydrochloric acid solution
into each graduate and invert several times.
ix) Continue with steps vi through ix of the soluble-ortho-
phosphate method. From the calibration curve read the
total-ortho-plus-hydrolyzable-phosphate content as PC>4 in
milligrams per liter.
188
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3. Calibration for Phosphate Methods
a. Calibration Solutions
i) Stock Phosphate Solution; Dissolve 0.7165 gram of anhydrous
potassium dihydrogen phosphate (Kr^PC^) in distilled water
and dilute to one liter with additional water.
ii) Standard Phosphate Solution: Dilute TOO milliliters of the
stock phosphate solution to one liter using distilled water.
iii) Test Phosphate Solutions: Dilute 2-, 4-, 8-, and 12-milli-
liter portions of the standard phosphate solution to 100
milliliters with distilled water. These test solutions will
contain 1-, 2-, 4-, and 6-milligrams per liter phosphate,
respectively.
b. Procedure
i) Obtain the absorbance of the above test phosphate solutions
by following the procedure (Section l-b) described in the
soluble-ortho-phosphate method, eliminating the nitrogen
sparge.
ii) Plot the absorbance at 800 millimicrons vs milligrams per
liter phosphate
L. Sulfate - Sulfate concentrations were measured using the Turbidimetric Method
presented in Standard Methods (21). The analysis was investigated and no inter-
ferences were found in the anaerobic system.
M. Sulfide - Methods were developed for accurate determinations of both total
and soluble ionic sulfide concentrations in the anaerobic-lagoon system. The
methods are itemized below:
1. Total Sul fides
a. Purpose and Limitations - This method is designed for the determination
of both soluble and insoluble ionic sulfide concentrations. By
employment of this method and the method for soluble sulfide con-
centration, it is possible to calculate the insoluble sulfide concen-
tration. The insoluble sulfide is generally regarded as the sulfide
of heavy metals.
189
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b. Principle - The sulfides are isolated by the addition of hydrochloric
acid to the sample. The acid converts all the sulfides to hydrogen
sulfide which is driven from solution by heating and a nitrogen purge.
The hydrogen sulfide gas is then bubbled into a solution of zinc
acetate and precipitated as zinc sulfide. The zinc sulfide precipitate
is isolated, washed, and treated with a known amount of acidic
silver nitrate solution, which yields a silver sulfide precipitate. By
determination of the concentration of unreacted silver ion with
chloride ion, it is possible to calculate the concentration of total
ionic sulfide in the sample. The following reactions are utilized in
this method:
S2-+ 2H+ -> H2S
H2S + Zn++ + 2OAc-. > _ZnS + 2HOAc
ZnS + (excess), Ag + NO3~ Acidic > Ag2S + Zn(NO3)2 +AgNO3
Ag+ + Cl- > AgCI
c. Reagents and Apparatus
i) Zinc Acetate Reagent: Dissolve 22 grams of Zn(OAc)2-
2H2O in 100 milliliters of distilled water.
ii) Sodium Hydroxide Solution: Dissolve four grams of NaOH
in TOO milliliters of distilled water.
iii) Silver Nitrate Solution 0.01 N Ag /O.I N HNO3: To 500
milliliters of distilled water add 6.25 milliliters of c.p.
HNO3; after cooling this solution, add 1.698 grams of
AgNO3 and bring the volume to one liter with distilled
water.* Take care.
iv) Hydrochloric Acid, Dilute Solution: To 500 milliliters of
distilled water, add 250 milliliters of c.p. hydrochloric acid
and then bring to a volume of one liter with distilled water.
Standardize the silver nitrate solution potentiometricallyby titrating 25 milliliters
of the solutittf) in 100 milliliters of distilled water using 0.01 N HCI.
190
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v) Hydrochloric Acid: Standard 0.01 N aqueous solution.
vi) pH Meter: Beckman Zeromatic* or its equivalent.
vii) Electrode System - Reference Electrode: Double-function-
sleeve type, Beckman* Part No. 40452; Indicator Electrode:
silver billet, Beckman* Part No. 39261 - or equivalent.
d. Procedure
i) Set up the hydrogen sulfide generator as shown in the
attached Figure 41. Purge the system with nitrogen
(200 to 300 cubic centimeters per minute) through inlets A
and B with the final purge through inlet B.
ii) Introduce 100 milliliters of dilute hydrochloric acid in the
addition funnel with the addition funnel's stopcock closed.
iii) Remove the condenser and add the sample (c); the system
should still be under a nitrogen purge. Replace the condenser
and attach the delivery tube as shown in Figure 40.
iv) Immerse the delivery tube to within approximately one
centimeter of the bottom of the collection vessel. The
collection vessel is a 100-mi Mi liter glass-stoppered graduated
cylinder containing one milliliter of zinc acetate solution
and 74 milliliters of distilled water.
v) Open the stopcock on the addition funnel and simultaneously
transfer the nitrogen pressure from inlet B to inlet A, thus
introduce the dilute hydrochloric acid into the reaction
vessel.
vi) Allow the system to remain in this configuration until the
solution comes to a boil; then transfer the purge to inlet B,
closing the addition funnel's stopcock.
vii) The generation should be allowed to proceed for a period of
30 minutes. The purge is then transferred back to inlet A
for a period of five minutes.
viii) At this time the collection vessel is removed.
* Beckman Instruments Inc., Fullerton, California
191
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FIGURE 40
HYDROGEN SULFIDE GENERATOR
Tension
Holddowns
12/5 female
500 ml
Delivery tube
in 100 milli-
lirer ground
glass stoppered
graduate
192
-------
ix) Add one mill? liter of 1 N sodium hydroxide via a pipet to the
collection vessel, bring the volume to 100 milliliters with
distilled water and invert several times.
x) Allow the resulting precipitate to settle and remove the
precipitate from solution by gravity filtration employing
Whatman No. 4 filter paper.
xi) Wash the collection vessel with two 10-milliliter portions of
distilled water, pouring the washings over the precipitate.
xii) Wash the precipitate with an additional 125 milliliters of
distilled water, added by at least four additions.
xiii) Transfer the filter paper, containing the precipitate to a 200-
milliliter electrolytic beaker. Next add 75 milliliters of
distilled water to the beaker.
xiv) Stir the solution with a magnetic stirrer beating the filter
paper into small pieces. To the solution containing the
small pieces of paper, add 40 milliliters of 0.01 N silver
nitrate solution by means of a buret with continuous stirring
of the solution.
xv) Titrate the solution potentiometrically with 0.01 N hydro-
chloric acid. A typical titration curve is shown in Figure 41.
e. Calculation
(ANAa-BNHC,)16030
sample volume (nil) ~ liter
where A is the milliliters of 0.01 N silver nitrate, normally 40 as
suggested in the above procedure; B is the milliliters of 0.01 N
hydrochloric acid; N/\g is the normality of silver nitrate; and
's ^ne normality of hydrochloric acid.
2. Soluble Sulfides
a. Purpose and Limitations - This method is designed for the determination
of ionic sulfides that are dissociated in a waste-stream sample. This
method will not detect the insoluble sulfides (sulfides of heavy metals).
The soluble sulfides are those which would cause most concern in an
anaerobic system.
193
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FIGURE 41
TITRATION CURVE
50 nil ssimple size
Uo ml 0.01 N silver nitrate reagent
0*0.00 x 0.01 - 21.60 x O.Qll 16Q3Q
50
52 ffl«/l S
10
11
12
13
li.
15
16
17 18 19 20 21 22 23
0.01 IJ Hydrochloric Acid Titrant, mis
21*
25
26
27
30
-------
b. Principle - The ionic sulfide is removed from other interfering ions in
the waste-stream sample by precipitation of the sulfide as zinc
sulfide, followed by a filtration of the precipitate. The precipitate
is then treated with a known amount of acidic silver nitrate solution,
which yields a silver sulfide precipitate. By determination of the
unreacted silver ion via a potentiometric titration using standardized
hydrochloric acid as the titrant, it is possible to calculate the concen-
tration of soluble sulfide in the waste-stream sample. The following
reactions are utilized in this method:
S2" + Zn2 + - > ZnS
_L O-4- _L
ZnS + excess Ag - ^> Ag2S + Zn + Ag (excess)
A 4. _._ acidic ^ . _.
Ag^ + Cl >AgCI
c. Reagents and Apparatus
i) Zinc Acetate Reagent: Dissolve 22 grams Zn(OAc)2'2H2O
in 100 milliliters of distilled water.
ii) Sodium Hydroxide Solution, 1 N: Dissolve four grams
NaOH in 100 milliliters of distilled water.
iii) Silver Nitrate Solution, 0.01 N Ag /O.I N HMC^: To 500
milliliters of distilled water add 6.25 milliliters of c.p.
nitric acid; after cooling this solution, add 1 .698 grams
of AgNOo and bring the volume to one liter with distilled
water.*
iv) Hydrochloric Acid, Standard 0.01 N Aqueous Solution:
v) pH Meter: Beckman Zeromatic**, or its equivalent.
vi) Electrode jystern - Reference Electrode: Double-junction-
sleeve type, Beckman Part No. 40453; Indicator Electrode:
silver billet, Beckman Part No. 39261 - or their equivalent.
* Standardize the silver nitrate solution potentiometrically by titrating 25 milliliters
of the solution in 100 milliliters of distilled water using standard 0.01 N HCI.
** Beckman Instruments Inc., Fullerton, California
195
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d. Procedure
i) If the sample* contains solids, they should be removed by
gravity filtration employing Whatman No. 4 paper.
ii) Pipet one mi Hi liter of the zinc acetate solution into a 100-
milliliter, glass-stoppered graduated cylinder.
iii) Introduce 25 ml to 50 ml** of sample to the graduated
cylinder, bring the volume to 99 milliliters with distilled
water and invert several times.
iv) Add one milliliter of 1 N sodium hydroxide via a pipet to
the graduated cylinder and invert several times.
v) Allow the resulting precipitate to settle and remove the
precipitate from the solution by gravity filtration employing
Whatman No. 4 filter paper.
vi) Wash the cylinder with two 10-milliliter portions of distilled
water, pouring the washings over the precipitate.
vii) Wash the precipitate with an additional 125 milliliters of
distilled water added by at least four additions.
viii) Transfer the filter paper containing the precipitate to a 200-
milliliter electrolytic beaker, followed by the addition of
75 milliliters of distilled water.
ix) Stir the solution with a magnetic stirrer breaking the filter
paper into small pieces. To the solution containing the
small pieces of paper, add 40 milliliters of 0.01 N silver
nitrate solution by means of a buret, with continuous stirring
of the solution.
x) Titrate the solution potentiometrically with 0.01 N hydro-
chloric acid. A typical Htrqtion curve is illustrated in
Figure 41.
Samples should be stabilized at the time of sampling by adjusting the pH to
approximately 11.5. Otherwise the sulfide may be oxidized and/or lost via
volatile hydrogen sulfide prior to being analyzed.
Sample size will be determined by the expected sulfide concentration and can best
be determined employing the formula in the calculation.
196
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e. Calculation
(ANA -BNHa) 16030 _ milligrams S2'
sample volume (ML) liter
where A is the millilirers of 0.01 N silver nitrate, normally 40 as
suggested in the above procedure; B is the milliliters of 0.01 N
hydrochloric acid; N^g is the normality of silver nitrate; and
's tne normality of hydrochloric acid.
N. Suspended Solids (SS) and Volatile Suspended Solids (VSS) - Suspended-solids
concentrations were measured using the technique given in Standard Methods (21)
except that a glass-fiber filter was substituted as the filter media. Volatile-solids
concentrations were determined by measuring the difference between solids concen-
tration before and after ignition at 600°C.
O. Total Carbon (TC) and Total Organic Carbon (TOC) - TC and TOC measure-
ments were made on filtered samples using the Union Carbide Total Carbon Analyzer.*
Total carbon was measured directly on the filtered samples while TOC was measured
after inorganic carbon compounds were removed from the filtered samples by
acidification to a pH below 4.3 and sparging with nitrogen gas.
P. Volatile Acids ^V.A) * VoJqtiJe-qcids concentrations were determined as
specified in Standard
II. Experimental Apparatus
A. Anaerobic Filters
Bench-Scale Filters - Bench-scale submerged filters were fabricated from
Plexiglas tubing with an inside diameter of 3.5 inches. They were about two feet
long and packed with 1-inch Berl saddles, which provided void volume of about
3 liters, or 58 per cent. Both bench units were maintained at 35°C by electrical
heating tape wound around each tube. Units were fed from a nitrogen-mixed feed
container using a peristaltic pump. Effluent gas and liquid were separated in a
500-milliliter separatory funnel; the liquid was retained for analysis, while the
product-gas flow was monitored in a wet test meter.
Semi-Pilot Filters - Semi-pilot scale filters were fabricated from 12-inch
diameter stain less-steel tubes to provide six feet of packed bed height. Filters were
packed with 1-inch diameter, hand-graded river gravel to provide a 41 per cent
void volume of 14.2 gallons. Doughnut-shaped distribution rings were installed
* Union Carbide Instruments Division, White Plains, N. Y. (now Ionics Inc.,
Cambridge, Mass.).
197
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at 2-foot intervals to prevent short-circuiting along the wall. All three units were
insulated and thermostatically controlled at 35°C by electrical heating tape wound
about them.
Petrochemical waste adjusted for pH and organic concentration and to which
nutrients were added was fed by a peristaltic pump from 50-gallon, polyethylene-
lined drums. Product gas was measured with wet test meters and analyzed for
methane.
B. Contact Digesters
Bench-Scale Digesters - Bench scale contact digestion units consisted of
five-gallon carboys which were back-mixed and continuously fed. An active
volume of 16 liters was used. All units were mixed by recycling product gas with a
diaphragm-type gas pump to a submerged tee in the bottom of the reactor. Tube-type
and packed-bed clarifiers were tested as solids separation devices. Net product gas
was analyzed, and flow was metered.
The tube-type clarifiers used in the bench-scale studies consisted of a multiplicity
of 5-mm diameter tubes inside a 30-mm diameter tube inclined at an angle of approxi-
mately 45° with the horizontal. This type clarifier system exploits the theoretical
advantages of low hydraulic flow per unit area of clarifier. The inclined tubes are
self cleaning, the settled solids slide down the tubes back into the reactor or solids
recycle system. Sludge was recycled with a peristaltic pump back through the feed
line.
The packed-bed clarifiers were 1-inch O.D. by 12-inch long tubes packed with
either pea-sized gravel or 6-mm diameter glass beads. Waste flow was directed
upwards through the bed. The beds in these small units were back-flushed daily by
simply raising them until the solids and effluent were flushed back to the reactor
through the flexible connections used.
Semi-Pilot Digesters - The semi-pilot scale unit was a 5600-gallon below-
grade, steel vessel having a bottom diameter of 9 feet, a top diameter of 12.5 feet,
a liquid depth of 8 feet, and a removable steel cover. The waste was fed continuously
with a peristaltic pump from a 3000-gallon tank containing feed adjusted to pH 7 and
to which nutrients had been added. The digester contents were mixed hydraulically
with a centrifugal pump. The digester was maintained at 35°C by means of internal
coils using recycled hot water as the heat transferring agent. Solids were recovered
from the effluent by use of an internal tube-type clarifier. This clarifier consisted
of 49, two-inch diameter stainless steel tubes inclined at an angle of 60° with the
horizontal. The liquor flowed upward through the tube to an overflow box and thence
out of the digester through a gas-seal leg. Product gas was metered and analyzed.
198
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C. Anaerobic Lagoons
Semi-Pilot Lagoons - Semi-pilot scale studies were made treating an
actual petrochemical waste in anaerobic lagoons ranging in size from 50 gallons to
5500 gallons. With one exception, all units were cylindrical vessels of either
polyethylene-lined steel or stainless steel construction, open-topped and located
outdoors to take advantage of photosynthetic bacteria. The largest unit (5500
gallons) was a prismoid constructed of plywood having top dimensions of 24 by 18
feet and sides sloped at 45°. This latter unit is described in Figure 42. Submerged
influent and effluent connections were used in all units. Gas was not collected in
these units.
D. Demonstration Facility
The process consisted of the treatment of clarified, pH-adjusted wastewater in two
anaerobic lagoons followed in series by aerated stabilization and by facultative
lagoons for sludge separation and digestion.
Influent Pretreatment - Clarified petrochemical wastewater from the
Texas City Plant was mixed and pH adjusted in a 5600-gallon basin. Because the
wastewater was usually alkaline provisions were made for only the controlled
addition of sulfuric acid. Sulfuric acid was pumped from drums to a constant head
tank, or stand pipe, to provide constant pressure to an automatically controlled
motor valve. The excess acid overflowed the head tank and returned to the feed
drum. The controlled sulfuric acid flow from the head tank flowed through the motor
valve to the mixing tank. Dilute and at times concentrated wastewater plus metered
flows of nutrients, ammonium hydroxide (25%) and phosphoric acid (75%), were
pumped to the mixing basin. The contents of the basin were mixed hydraulically with
a centrifugal pump. A portion of the recycle stream from this pump passed through a
2-celled pH analyzer with the output signal used to control the addition of sulfuric
acid.
Anaerobic Lagoons - The rate of feed to the anaerobic lagoons was
controlled by a steam-driven reciprocating pump. The pretreated wastewater was
pumped to a surge chamber to dampen the pulsations and thence through a totalizing,
flowmeter. The total flow then passed through a weir-type flow splitter to split
the total flow, one-third to the shallow lagoon and two-thirds to the deep lagoon.
Thes.e two lagoons were similar in area (501 x 100') but different in depth; one
was six-feet deep, the other 12-feet deep. Upstream equipment was designed to
provide flows equivalent from 8 to 15 days (or longer) residence time in the anaerobic
lagoons. The lagoons were large in area to model more closely full scale with respect
to wind and wave action and their effects on reaeration and on mixing. In order to
199
-------
FIGURE 42
Anaerobic Pilot-Scale Reactor
Submerged
Influent
Recycle
Siphon
Effluent
J
1
y
\
\/
\
\
\
L \
/
_ _
?/'
/
/
/
i
>/ / ,»,.if i
\
\
\
\
\
\
/
\
18'
Effluent
Recycle
Influent
Submerged Dam
Partition
200
-------
increase the similarity, free-board was low at one foot to allow good wind action.
Straight vertical sides were used to obviate any effects of a difference in top and
bottom surface area.
Because of the uncertainty on the relative effects of the anaerobic bottom and
aerobic surface, combined with mixing and aeration, two lagoon depths, 6 and
12 feet, were used. The direction of placement was selected so that the dividing
wall common to both lagoons extended in a north-south direction to ensure that both
lagoons received equal periods of light from the sun. Another feature was that the
direction of water flow was opposite to the prevailing southeasterly wind direction to
reduce the opportunity for short circuiting by warmer water being blown across the
upper portion of the lagoons to the outfall.
Inlets and outlets were simple tees located at the midpoint of opposite ends of the
lagoons. More exotic distribution or collection systems were thought to be un-
necessary since outlets in a full-scale lagoon likely would be no less than fifty feet
apart due to distribution achieved by input velocity and wind action.
The influent wastewater flowed through submerged inlets through the lagoons to
submerged, vented overflows. Since only a portion of the stream was to be treated
aerobically, provisions were made to collect and dispose of the excess anaerobic
lagoon overflow. Both lagoons overflowed to a sump. Connections to each or both
lagoon-overflow lines were used to provide treated water for the aerated-stabilization
feed pump. Excess anaerobic lagoon overflow was transferred from the sump by pumps
to a disposal basin.
Aerated Stabilization - Anaerobically treated wastewater from either,
or both, anaerobic lagoons was pumped at a controlled rate by a steam-driven
reciprocating pump to a surge chamber for pulsation damping. The wastewater flowed
from the surge chamber through a totalizing water meter to the aerated-stabilization
unit for further organic reduction.
The aerated stabilization unit utilized a variable-speed Yoemans1* cone surface
aerated and later a high speed Ashbrook aerator** installed in the 31,000-gallon
basin (9 ft deep,7 ft square bottom, 30 ft square surface).
The effluent from the aerated-stabilization unit flowed by gravity to lagoons for
solids separation and stabilization.
* The Clow Co., Melrose Park, III
** Ashbrook, Inc., Houston, Texas
201
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Sludge Separation and Stabilization - Solids contained in the aerated-
stabilization unit effluent were removed in the facultative lagoons by gravity
settling. Two lagoons in series were used, each one provided two days' detention
time with the aerated stabilization unit operating at a 3-day detention time. The
primary function of these lagoons was solids removal as little or no removal of
soluble COD or BOD5 was expected. Lagoons were 13 ft wide by 26.5 ft long by
6 ft deep each.
Sampling - Provisions were made for collecting 24-hour composite
samples of major streams. In order to ensure representative material the samples
were held in ice-cooled containers to prevent degradation during the collection
period.
202
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1
Accession Number
w
5
Q Subject Field & Group
05D
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
Organization
and Development Department, South Charleston, West Virginia
Title
ANAEROBIC TREATMENT OF SYNTHETIC ORGANIC WASTES
10
22
Author(s)
Hovious, Joseph C.
Fisher, John A.
Conway, Richard A.
if Project Designation
EPA, ORM Project No. 12020-DI5
21 Note
Citation
23
Descriptors (Starred First)
*Chemical Wastes, *lndustrial Wastes, *Anaerobic Digestion
25
Identifiers (Starred First)
*Anaerobic Lagoons, *Anaerobic Filter, *Contact Digester, Anaerobic-Aerobic Processes
27
Abstract
Bench, semi-pilot, and pilot scale studies of three anaerobic treatment processes have
shown the anaerobic lagoon to be both the performance and the economic choice for pretreatment
of petrochemical wastes in warm, spacious locations. Semi-pilot scale studies of anaerobic contact
digesters and packed bed reactors indicated performance problems when treating actual petrochemical
wastes. Experimental data from several sources were combined to prepare a design procedure for
anaerobic lagoon pretreatment systems.
Operation of a large (30 gpm) pilot plant consisting of anaerobic lagoons followed by
aerated stabilization and facultative ponds provided a BOD removal from the petrochemical wastes
of greater than 90 percent and a resistance to both organic-loading and pH shocks. Comparison of
an anaerobic-aerobic system with a strictly aerobic system pointed out an economic advantage
with the series system due to lower sludge-dispose I and oxygen requirements.
.Abstractor
Hovious, Joseph C.
Institution
Union Carbide Corporation
WR:I02 (REV. JULY 1969)
WRSIC
SEND, WITH COPY OF DOCUMENT. TO: WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON. D.C. 20240
* GPO: 197U-389-930
OU.S. GOVERNMENT PRINTING OFFICE: 19 7 2 484-486/248 i-j
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