EPA-660/2-73-038
MARCH 1974
Environmental Protection Technology Series
Deepwater Pilot Plant
Treatability Study
Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were established to facilitate further
development and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
<*. Environmental Monitoring
5. Socioeconomic Environmental studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards.
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EPA-660/2-73-038
March 1974
Final Report
DEEPWATER PILOT PLANT TREATABILITY STUDY
by
Delaware River Basin Commission
P.O. Box 360
Trenton, N. J. 08603
Project Officer
Gilbert Horwitz
Environmental Protection Agency
Region III
Philadelphia, Pennsylvania 19106
Project No. 11060-DRO
Program Element 1BB036
Prepared for
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price $4.10
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EPA Review Notice
This report has been reviewed by the Environmental Protection Agency and
approved for publication. Approval does not signify that the contents necessarily
reflect the views and policies of the Environmental Protection Agency nor does
mention of trade names or commercial products constitute endorsement or
recommendation for use.
ii
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ABSTRACT
The Delaware River Basin Commission initiated a study of a joint industrial-
municipal regional wastewater collection and treatment system for southern New
Jersey. Staff personnel determined an optimum collection area for ten industrial
plants and inclusive municipalities.
Engineering-Science, Inc. was selected as design and operating engineers of a
50 gpm pilot plant to treat a composite of refinery, petrochemical, and municipal
wastewater „
Raw wastewater was subjected to the following processes: pretreatment, equali-
zation, neutralization, primary clarification, varied types of activated sludge,
final clarification, and intermittent varied testing on polishing and disinfection.
The activated sludge process, at optimum conditions, removed 90 percent of the
BOD of the strong predominately industrial waste. The raw wastewater color
ranged from 400 to 1200 units color which was readily removed by carbon sorption
of the activated sludge effluent.
Aerobic digestion reduced excess activated sludge volatile suspended solids 50
percent in 20 days. Either vacuum filtration or filter pressing would be most
applicable for dewatering.
Pilot plant operation confirmed treatability proposals, developed design criteria
and pointed out areas of concern for additional study.
This report was submitted in fulfillment of Project Number 11060-DR0 under the
sponsorship of the Environmental Protection Agency.
• • *
in
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CONTENTS
Section
I Preface 1
II Conclusions and Recommendations 7
III Introduction 13
IV Wastewater Characterization 19
V Bench Scale Treatability Studies 57
VI Pilot Plant Treatability Studies 169
VII Conceptual Design and Treatment Cost Estimated 367
VIII Effluent Quality Analysis 385
Appendix 401
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FIGURES
JPage
P-l Proposed Deepwater Regional Sewerage System 3
1 Activity Plan Pilot Plant Preliminary Engineering
Study 15
2 Variation in the Pilot Plant Composite Wastewater
Organic Parameters 53
3 Variation in the Pilot Plant Composite Wastewater
Solids 54
4 Variation in the Pilot Plant Composite Wastewater
pH 55
5 Titration Curve for Integrated Wastewater 76
6 Bench Scale Biological Reactor Flow Diagram 85
7 Bench Scale Biological Reactors 86
8 Substrate Removal Rate 92
9 Oxygen Requirements and Sludge Production 93
10 Percent Removal of BOD5 and COD for Wastewater 510 102
11 Percent Removal of BOD5 and COD for Wastewater 210 103
12 Percent Removal of BOD5 and COD for Wastewater 220 104
13 Percent Removal of BOD5 and COD for Wastewater 230 105
14 Percent Removal of BOD5 and COD for Wastewater 240 106
15 Percent Removal of BOD5 and COD for Wastewater 260 107
16 Percent Removal of 8005 and COD for Wastewater 280 108
17 Percent Removal of BOD and COD for Wastewater 290 109
VI
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FIGURES (continued) Page
18 Percent Removal of BODg and COD for Wastewater 300 110
19 Filtered Effluent Concentrations for the Integrated
Wastewater 1 14
20 Determination of Kinetic Coefficients Based on BOD5
for Wastewater 510 115
21 Determination of Kinetic Coefficients Based on BOD5
for Wastewater 210 116
22 Determination of Kinetic Coefficients Based on BOD.
for Wastewater 220 1 17
23 Determination of Kinetic Coefficients Based on BOD5
for Wastewater 230 1 18
24 Determination of Kinetic Coefficients Based on BOD5
for Wastewater 240 1 19
25 Determination of Kinetic Coefficients Based on
for Wastewater 260 120
26 Determination of Kinetic Coefficients Based on BODc
for Wastewater 280 121
27 Determination of Kinetic Coefficients Based on BODc
for Wastewater 290 122
28 Determination of Kinetic Coefficients Based on
for Wastewater 300 123
29 Determination of Kinetic Coefficients Based on COD
for Wastewater 510 124
30 Determination of Kinetic Coefficients Based on COD
for Wastewater 210 125
31 Determination of Kinetic Coefficients Based on COD
for Wastewater 220 126
32 Determination of Kinetic Coefficients Based on COD
for Wastewater 230 127
VII
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FIGURES (continued) Page
33 Determination of Kinetic Coefficients Based on COD
for Wastewater 240 128
34 Determination of Kinetic Coefficients Based on COD
for Wastewater 260 129
35 Determination of Kinetic Coefficients Based on COD
for Wastewater 280 130
36 Determination of Kinetic Coefficients Based on COD
for Wastewater 290 131
37 Determination of Kinetic Coefficients Based on COD
for Wastewater 300 132
38 Oxygen Transfer by Diffused Aeration Load 0.25 Ib
BOD^Ib MLVSS/day 138
39 Oxygen Transfer by Mechanical Aeration Load 0.25
Ib BOD^Ib MLVSS/day 139
40 Oxygen Transfer by Diffused Aeration Load 0.5 Ib
BODy'lb MLVSS/day 140
41 Oxygen Transfer by Mechanical Aeration Load 0.5 Ib
BODg/lb MLVSS/day 141
42 Oxygen Transfer by Diffused Aeration Load 1.0 Ib
BOD^Ib MLVSS/day 142
43 Oxygen Transfer by Mechanical Aeration Load 1.0 Ib
BODy% MLVSS/day 143
44 Zone Settling Curves for Individual Wastewaters Load
0.25 Ib BOD^Ib MLVSS/day 146
45 Zone Settling Curves for Individual Wastewaters Load
0.50 Ib BODyib MLVSS/day 147
46 Zone Settling Curves for Individual Wastewaters Load
1.0 Ib BOD5/lb MLVSS/day 148
47 Zone Settling Curves for Integrated Wastewater 149
VIII
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FIGURES (continued) Page
48 Zone Settling Velocity for Integrated Wastewater 150
49 Freundlich Isotherm for COD 158
50 Freundlich Isotherm for MBAS 159
51 Freundlich Isotherm for Phenol 160
52 Proposed Control Tests for Pilot Plant Evaluation 165
53 Process Flow Diagram Deepwater Pilot Plant 170
54 Delaware River Basin Commission Deepwater Pilot
Plant: Site Preparation 171
55 Delaware River Basin Commission Deepwater Pilot
Plant: Site Piping Plan 172
56 Delaware River Basin Commission Deepwater Pilot
Plant: Water Surface Profile 173
57 Delaware River Basin Commission Deepwater Pilot
Plant: Schematic Piping Layout 174
58 Delaware River Basin Commission Deepwater Pilot
Plant: Control Building 175
59 Delaware River Basin Commission Deepwater Pilot
Plant: Electrical Site Plant 176
60 Photographs of the Deepwater Pilot Plant 177
61 Theoretical Dye Recovery Curves for a Completely
Mixed System with Varying Amounts of Dead Space 182
62 Theoretical Dye Recovery Curves for a Completely
Mixed System with Varying Amounts of Plug Flow 183
63 Theoretical Dye Recovery Curves for a Completely
Mixed System with Varying Amounts of Dead Space
and Plug Flow 184
64 Dye Study for Equalization Tank, 21 March 1970 187
IX
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FIGURES (continued) Page
65 Dye Study for First Stage Neutralization System,
13 March 1970 188
66 Dye Study for Two-stage Neutralization System,
13 March 1970 189
67 Dye Study Reactor Clarifier W/Turbine Off, 16
March 1970 190
68 Dye Study Reactor Clarifier W/Turbine on at .25
Max. Speed, 16 March 1970 191
69 Dye Study for Aeration Tank B, 27 March 1970 192
70 Dye Study for Aeration Tank C, 27 March 1970 193
71 Dye Study for Secondary Clarifier Overflow Before
Modifications, 4 March 1970 194
72 Dye Study for Secondary Clarifier Underflow Before
Modifications, 4 March 1970 195
"73 Dye Study for Secondary Clarifier Overflow After
Modifications, 9 March 1970 196
74 Dye Study for Secondary Clarifier Underflow After
Modifications, 9 March 1970 197
75 Dye Study for Secondary Clarifier Overflow After
Modifications, 13 March 1970 198
76 Dye Study for Secondary Clarifier Underflow After
Modifications, 13 March 1970 199
77 Surface Aerator Characteristics 206
78 Air Operated Automatic Sampling System for Pilot
Plant 215
79 Pilot Studies Operation Schedule 221
80 Pilot Plant Organic Loadings and Oxygen Uptake 223-224
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FIGURES (continued) Page
81 Pilot Plant Efficiency - COD Removal 225-226
82 Pilot Plant Efficiency - BOD5 Removal 227-228
83 Pilot Plant Mixed Liquor Conditions 229-230
84 Percent BOD^ - COD Removal (Total) vs.
Aeration Time 232
85 Percent BOD - COD Removal (Across Aeration
Tank) vs. Aeration Time 233
86 Aeration Basin Temperature vs. Removal Efficiency 237
87 January Temperatures for Wilmington, Del., Based
on 20 Year Period 241
88 Aeration Basin Temperature vs. Basin Inlet Temperature
for January Conditions Deepwater Regional Treatment
Plant 245
89 Removal Velocity vs. Effluent BOD5 (Soluble) 250
90 Sludge Growth Rate vs. Removal Velocity (BOD5
Basis) 251
91 Unit Respiration Rate vs. Removal Velocity
Basis) 252
92 Removal Velocity vs. Effluent COD 253
93 Sludge Growth Rate vs. Removal Velocity (COD
Basis) 254
94 Unit Respiration Rate vs. Removal Velocity (COD
Basis) 255
95 Bench Scale Aerobic Digestion Results - Solids
Reduction and Oxygen Utilization - Unit 1 260
96 Bench Scale Aerobic Digestion Results - Solids
Reduction and Oxygen Utilization - Unit 2 261
XI
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FIGURES (continued) Page
97 Bench Scale Aerobic Digestion Results - Solids
Reduction and Oxygen Utilization - Unit 3 262
98 Pilot Scale Aerobic Digestion Results - Solids Reduction
and Oxygen Utilization 263
99 Aerobic Stabilization of Volatile Solids 264
100 Pilot Filter Press Assembly 266
101 Filter Press Assembly 267
102 Filter Leaf Apparatus 270
103 Filter Leaf Test Results 272
104 Filter Leaf Test Results 274
105 Filter Leaf Test Results 275
106 Pilot Scale Centrifuges 278
107 Flow Diagram for Pilot Scale P-600 Centrifuge 280
108 Primary Sludge Recovery Curves (P-600) 282
109 Digested Sludge Recovery Curves (P-600) 283
110 Combined Sludge Recovery Curves (P-600) 284
111 Combined Sludge Recovery Curves (P-600) 285
112 Combined Sludge Recovery Curves (P-600) 286
113 Primary Sludge Recovery Curves - Fletcher 287
114 Operating Recovery Curve - P5400 75/25 Primary to
Secondary Sludge Ratio 289
115 Operating Recovery Curve - P5400 50/50 Primary to
Secondary Sludge Ratio • 290
116 Adsorption Isotherm - COD Untreated Wastewater 294
XII
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FIGURES (continued) Page
117 Adsorption Isotherm - COD Primary Treatment
Effluent 295
118 Adsorption Isotherm - COD Biological Treatment
Effluent 296
119 Adsorption Isotherm - Color Untreated Wastewater 297
120 Adsorption Isotherm - Color Primary Treatment Effluent 298
121 Adsorption Isotherm - Color Biological Treatment
Effluent 299
122 Carbon Column Testing Apparatus 303
123 Activated Carbon Column Performance Macro-Nutrient
Removal by Carbon Sorption 306
124 Phenol Removal from Untreated Wastewater 307
125 Phenol Removal from Biological Treatment Effluent
(4.5 gpm/ft2) 308
126 Phenol Removal from Biological Treatment Effluent
(9.8 gpm/ft2) 309
127 Activated Carbon Column Performance BOD5
Removal from Untreated Wastewater 310
128 Activated Carbon Column Performance COD
Removal from Untreated Wastewater 311
129 Activated Carbon Column Performance TOC Removal
from Untreated Wastewater 312
130 Activated Carbon Column Performance COD
Removal from Untreated Wastewater as a Function
of COD Applied 313
131 Activated Carbon Column Performance TOC Removal
from Untreated Wastewater as a Function of TOC
Applied 314
XIII
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FIGURES (continued) Pq9g.
132 Activated Carbon Column Performance COD Removal
for Primary Treatment Effluent 3l7
133 Activated Carbon Column Performance COD Removal
from Primary Treatment Effluent as a Function of
COD Applied 318
134 Activated Carbon Column Performance BOD5
Removal from Biological Treatment Effluent
(4.5 gpm/ft2) 319
135 Activated Carbon Column Performance BODc
^J
Removal from Biological Treatment Effluent
(9.8 gpm/ft2) 321
136 Activated Carbon Column Performance COD Removal
from Biological Treatment Effluent (4.5 gpm/ft2) 322
137 Activated Carbon Column Performance TOC Removal
from Biological Treatment Effluent (4.5 gpm/ft2) 323
138 Activated Carbon Column Performance COD Removal
from Biological Treatment Effluent (9.8 gpm/ft2) 324
139 Activated Carbon Column Performance TOC Removal
from Biological Treatment Effluent (9.8 gpm/ft2) 325
140 Activated Carbon Column Performance COD Removal
from Biological Treatment Effluent as a Function of
COD Applied (9.8 gpm/ft2) 326
141 Activated Carbon Column Performance TOC Removal
from Biological Treatment Effluent as a Function of
TOC Applied (9.8 gpm/ft2) 327
142 Activated Carbon Column Performance COD Removal
from Biological Treatment Effluent as a Function of
COD Applied (4.5 gpm/ft2) 328
143 Activated Carbon Column Performance TOC Removal
from Biological Treatment Effluent as a Function of
TOC Applied (4.5 gpm/ft2) 329
XIV
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FIGURES (continued) Page
•tfVWB^BVMMIWHI
144 Activated Carbon Column Performance Color Removal
from Biologically Treated Effluent (4.5 gpm/ft2) 330
145 Activated Carbon Column Performance Color Removal
from Biologically Treated Effluent (9.8 gpm/ft2) 331
146 Activated Carbon Column Performance Color Removal 332
147 Pilot Scale Carbon Column 334
148 Filtered COD vs. Volume Throughput, Activated Carbon
Study Test I 341
149 COD Removal from Biological Treatment Effluent as a
Function of COD Applied, Activated Carbon Study
Test I (Based on Filtered COD Analysis) 342
150 Color vs. Volume Throughput, Activated Carbon Study
Test I 343
151 COD versus Volume Throughput, Activated Carbon
Study - Test No. 2 344
152 COD Removal from Biological Treatment Effluent as a
Fucntion of Volumetric Throughput, Carbon Test No. 2 345
153 Influence of Breakthrough Curve Geometry on Carbon
Capacity Activated Carbon Study - Test No. 2 348
154 COD vs. Volume Throughput, Activated Carbon Study -
Test No. Three 349
155 Influence of Breakthrough Curve Geometry on Carbon
Capacity Activated Carbon Study - Test No. 3 350
156 Color Versus Volume Throughput, Activated Carbon
Study - Test No. 3 351
157 Organic Selectivity Through Combined Systems 353
158 Additional BOD^ - COD Removed in Powdered Carbon
Biological System 357
xv
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FIGURES (continued) Page
159 Effluent Color vs. Powdered Carbon Dosage 358
160 Typical Results for Pilot Upflow Sand Filter Experiments 361
161 Effect of Hydraulic Loading on Upflow Sand Filtration
System 362
162 Schematic of Proposed Activated Sludge - Carbon
Adsorption Treatment System 368
163 Conceptual Layout of the Deepwater Regional Treatment
Facilities 383
A-l Schematic of Computational Technique Program STATPK 403
A-2 Relationships for Determining Design Coefficients 412
XVI
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TABLES
Page
-i • • .< -, -. •
1 Participant Wastewater Flows 28
2 Characterization of Participant Wastewaters Bench
Scale Phase 29-38
3 Characterization of Participant Wastewaters Pilot
Plant Phase 39-49
4 Characterization of Combined Industrial and
Municipal Wastewaters Bench Scale Phase 50
5 Characterization of Combined Industrial and
Municipal Wastewaters Pilot Plant Phase 52
6 Equalization Basin Size Based on Storm Water Runoff 60
.7 Neutralization Requirements of Industrial Wastewaters 67
8 Cumulative Neutralization Requirements in Interceptor 68
9 Summary of Results for Flocculation Without pH
Adjustment 70
10 Summary of Results for Flocculation With pH
Adjustment 71
11 Results of Additional Coagulation and Flocculation
Studies 72
12 Summary of Effect of pH Adjustment on Solids in the
Integrated Wastewater 77
13 Summary of the Effect of pH Upon Heavy Metals in the
Integrated Wastewater 79
14 Sedimentation Analyses of Untreated Wastewater 81
15 Activity of Acclimated Seeds Dissolved Oxygen Uptake 84
16 Pre- or Primary Treatment Requirements 88
XVII
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TABLES (continued)
17 Computer Program for Treatability Studies 95-100
18 Effluent First Stage Oxygen Demand for Individual
Wastewaters at Various Loadings 112
19 Summary of Kinetic Coefficients 133
20 Summary of Oxygen Transfer Parameters 137
21 Mixed Liquor Thickening Results for the Integrated
Wastewater 151
22 Coliform Organisms in Industrial Wastewaters 153
23 Chlorine Demand of Industrial Wastewaters 155
24 Summary of Results for Activated Carbon Batch Study 161
25 Summary of Dye Study Results and Flow Characteristics 200
26 Oxygenation Capacity Determination 204
\
27 Individual Participant Contributions for the Integrated
Pilot Plant Wastewater Summer Loadings 208
28 Participant Wastewater Contributions Based on Trucking
Schedule 209
29 Deepwater Pilot Plant Trucking Schedule for Summer
Loading 210
30 Individual Participant Contributions for Integrated
Pilot Plant Wastewater Winter Loadings 211
31 Participant Wastewater Contributions Based on Revised
Trucking Schedule 212
32 Deepwater Pilot Plant Trucking Schedule for Winter
Loadings 213
33 Identification and Location of Sample Point Numbers 218
34 Daily Analytical Schedule for Pilot Plant 219
XVIII
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TABLES (continued) Page
35 Aeration Basin Heat Loss Comparison 240
36 ClimatoUgical Data for Proposed Treatment Site 240
37 Transient Loading Effects on the Biological System 247
38 Biological Design Coefficients 249
39 Pilot Scale Filter Press Results, Beloit-Ffcssavant
Filter Assembly, 6" Nominal Diameter 268
40 Vacuum Filtration Studies 273
41 Vacuum Filtration Constants 276
42 Centrifuges Tested at the Pilot Plant 277
43 Centrifuge Performance Summary 291
44 Activated Carbon Capacities from Isotherm Studies 300
45 Summary of Testing 315
46 Activated Carbon Column Results - 3.08 gpm/ft^
(Q = 21.8 gpm) 336-337
47 Activated Carbon Column Results - 2.4 gpm/ft2
(Q = 17 gpm) 338-340
48 Activated Carbon Column Results - 4.0 gpm/ft^
(Q = 28 gpm) 347
49 Summary of Carbon Capacity Values Bench and
Pilot Scale Carbon Columns 354
50 Results of the Conventional and Carbon Activated
Sludge Systems 356
51 Microstraining Results 364
52 Cost Estimates for the Regional Treatment Facility 384
XIX
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TABLES (continued) Page
53 Effluent Quality Requirements, Delaware River Basin
Commission 386
54 Predicted Effluent Quality of Biological Treatment
Based on Bench Scale Test 387
55 Observed Effluent Quality of the Pilot Biological
Treatment Plant 389
56 Observed Effluent Quality of the Pilot Carbon Columns 390
57 Gross Gamma Analyses (0-2.56 MeV) 396
58 Gross Beta Analyses 397
59 Predicted Effluent Quality 399-400
A-J Parameters Used in Process Design 410
xx
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SECTION I
PREFACE
Onset of Regionalization
The DRBC established Standards for water quality control in April 1967. After
adoption of the Standards, there was considerable local interest in regionalization
to minimize waste treatment costs, particularly by industry. This reaction re-
inforced the Commission Director's feeling that serious and detailed thought should
be given to regionalization, particularly along the Delaware Estuary.
Pollution Abatement for the Delaware Estuary
The most critical water quality problem area in the Delaware River Basin is the
86 mile long Estuary stretching from Trenton, New Jersey to Liston Point, Delaware.
The Estuary receives waste discharges from a complex, broad spectrum of industry
and several ma|or cities: Philadelphia, Pennsylvania; Trenton, New Jersey;
Wilmington, Delaware; Camden, New Jersey; and Chester, Pennsylvania.
To meet or exceed the dissolved oxygen concentration set by the Standards anal also
sustain the other uses specified by DRBC, the capacity of the Estuary to accept
waste was allocated among the dischargers. Based on the Year 1964 raw wastewater
data, treatment reductions of approximately 88% of the first stage oxygen demand
are required. With the growth anticipated in this area, higher treatment reductions
may be necessary by Year 1990.
Initial Development of Deepwater Regional Study
The Deepwater area extending some 30 miles in Gloucester and Salem Counties
in southern New Jersey appeared to be economically and practically favorable
for waste treatment regionalization.
An abbreviated preliminary evaluation of the technical feasibility of a two-coMnty
regional waste treatment facility in the vicinity of Deepwater, New Jersey wds
conducted by DRBC staff in January 1968. The determination of the boundary 'of the
collection system for regionalization was based on balancing the cost advantages of
a regional treatment facility against the cost of interceptors to convey wastes to
the central location. Preliminary indications showed that the optimum 130 MOD
collection system would extend from ihe City of Salem, Salem County to Mobil
Oil Corporation, Gloucester County with the regional treatment at Deepwater,
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New Jersey adjacent to the DuPont-Chambers Works plant which had the bulk of
the flow. Subsequent development showed that inclusion of Texaco, Inc. further
upriver from Mobil would serve the purpose of covering all major riverfront
industries in Gloucester County; the significant industries in Salem County were
already included. In addition, municipal wastes within the collection area of
the two counties would be included in the regional system. The system would
extend from the regional treatment facility 23 miles upriver to Texaco and 9
miles downriver to the City of Salem. Ten industrial plants and four municipalities
were considered for the collection area. This area is shown on the following map.
Mathematical model evaluation conducted by DRBC showed an overall improvement
in the dissolved oxygen profile by translating the wastes to the proposed regional
plant and outfall. There appeared to be about a 10% cost advantage for the
regional system based on total annual costs for initial development considering
amortization and operation and maintenance .
Meetings were held with the industries and municipalities and these showed
favorable support to continue the study.
Study Proposals
It was decided that an in-depth study by a consulting firm would be required to
delineate the collection area, determine a preliminary engineering cost estimate
of the project and develop these details necessary to determine treatability. The
project was divided into two basic studies: a pilot plant study to determine
treatability and a traditional preliminary engineering study that would be developed
concurrently with the pilot plant study. It was envisioned that the pilot plant
study would eventually have a feed-back into the costs pertaining to the preliminary
engineering for the treatment facility. This report encompasses the pilot plant
operations.
Pilot Plant Study
The specific objectives of the pilot plant study were:
a. to determine the treatability characteristics of the composite industrial and
municipal wastes;
b. to develop design criteria for the facility to achieve 90-95% BOD reduction
as well as to meet other effluent quality requirements;
c. to test methods of secondary and advanced waste treatment of combined
municipal and industrial wastes;
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\ proposed deepwater regional sewerage system \
aalem ami gloucester counties, n. j.
Cxlmtlng Dischargers In OMywafw- Study
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d. to estimate cost of construction and operation of the facility;
e. to provide data on which to base an equitable apportionment of the cost
among the industries and municipalities to be served; and
f. to demonstrate the expedituous and timely resolution of the technical and
economic difficulties of achieving a regional solution to a complex multi-
industrial and multi-waste disposal problem.
The pilot plant was planned to operate continuously at 50 gpm, 7 days per week,
24 hours per day. Wastewater was to be composited with projected loads and
flows so as to be representative of the influent to the proposed regional waste
treatment plant. Of the 50 gpm entering the pilot plant, it was estimated 44 gpm
to be industrial wastewater and 6 gpm municipal.
Wastes from the nearby DuPont-Chambers Works would be conveyed to the pilot
plant by ditch flow. Tank trailers were envisioned to convey the composite waste
from each industry. It was envisioned that several tank trailers would bring
in the waste from varied distances between 2 and 25 miles from the pilot plant.
Treatment processes proposed were equalization, neutralization, primary clari-
fication, aeration, final clarification, polishing, chlorination and sludge
disposal. The aeration basin was to be designed to provide flexibility for various
methods of the activated sludge process.
Funding
Federal funding assistance was solicited and an EPA Research and Development
grant offer of $646,700 or 67% of eligible project costs for the pilot study was
received on March 24, 1969.
On May 21, 1969, ten industrial plants and four municipalities agreed to contribute
up to $654,300 to fund a portion of the pilot plant study and all of the total
preliminary engineering study. The DRBC agreed to contribute $75,000.
Contract for Engineering Services
A contact was entered into between the DRBC and Engineering-Science, Inc., on
June 27, 1969 for the major part of the studies including the preliminary engineering
studies and the design, construction, and operation of the pilot plant and evaluation
of data.
The timetable included: (1) completion of an interim preliminary engineering
report not later than 6 months after date of the contract; (2) construction and
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operation of the pilot plant not later than 6 months after date of the contract;
(3) completion of the final report on the preliminary engineering studies not later
than one year from date of contract; (4) completion of the interim report on pilot
plant treatment studies not later than 18 months after date of contract; and
(5) completion of a final report of pilot plant studies not later than 3 years from
date of the contract. Scheduled dates were met.
Project Status at Completion of Pilot Plant Study
At the completion of the study, the industries were unwilling to agree to participate
in full scale regional treatment without guarantees of state and federal construction
grants. Such guarantees could not be met which was a major cause of the full scale
regional system not developing. The basis for industrial resistance was that approxi-
mately one-quarter of the construction cost of the initial project was the incremental
cost for system capacity for future participants. Industry did not want to subsidize
facilities for other, possibly competitive, industry without a guarantee of public
aid. However, one of the alternate plans of regional treatment with the dischargers
split into two regional systems - upriver and downriver portions - is presently being
pursued at county level.
The data gathered as the result of the pilot plant operations have been utilized
by several of the participating entities. The study engendered considerable interest,
nationwide, and a numb er of requests have been received for copies of the report.
This project provided an example of a solution to a difficult problem that could
be applied nationwide.
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SECTION II
CONCLUSIONS AND RECOMMENDATIONS
An analytical and treat-ability program for an area-wide industrial and municipal
treatment facility has been consummated and found to be sufficiently complete to
develop design information. The bench and pilot scale testing programs, covering
a period of 30 months, were established to obtain the design coefficients and
parameters. On this basis, cost estimates were formulated for a proposed regional
treatment system which could serve industries and municipalities in the lower
Delaware River Basin.
CONCLUSIONS
An analyses of data accumulated during the course of this project and presented
in the report has resulted in the following conclusions and observations.
Wastewater Characterization
1. The wastewaters from each of the participating industries were characterized
with respect to their organic and inorganic quality. This characterization schedule
was implemented during both the bench scale and pilot plant phases of this
project. The analytical results indicate that the combined wastewater conveyed
to the regional treatment system will have the following general characteristijcs:
Chemical Oxygen Demand (COD) 420-822 mg/l
Biochemical Oxygen Demand (BOD) 136-453 mg/l
Total Organic Carbon (TOC) 109-358 mg/l
Phenols 1-19 mg/l
Phosphates 0.2-13 mg/l
Total Kjeldahl Nitrogen 10.5-45 mg/l
Color 200-1800 Std. Co. Units
2. It is recognized that the aforementioned concentrations of organic constituents
as well as inorganic levels will fluctuate with both seasonal and operational
variations. Although one must recognize the factors which are prevalent when
interpreting these data—namely, sampling methods and frequencies, analytical
procedures, interferences, etc.—it does provide a rational approach for establish-
ing an individual and collective characterization picture of the combined waste-
water which must be treated in the regional system. It is from this information
that plant design, cost evaluations, and cost allocations must be formulated.
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Bench Scale Treatability Studies
1. Based on studies and considerations established during the early phases of
this project, the need for an equalization basin at the site of the regional
wastewater treatment plant does not appear to be economically attractive or
economically justified.
2. The results of neutralization studies conducted during this phase of the
project indicate that approximately 8.7 meq/l of lime are required for neutrali-
zation. The most acidic conditions encountered during the analytical program
required approximately twice as much lime as normally required. As unusual
operating conditions would have to appear simultaneously at several of the
participating plants, it is doubtful that the pH of the unneutralized stream would
ever be above 7.0. The need for acid neutralization is therefore not envisioned.
3. The results of the coagulation-precipitation studies indicated that chemical
precipitation of the combined wastewater flow at the regional plant as a method
of removing organic constituents is not justified.
4. It is estimated that 95 percent of the BOD5 contained in the. combined waste-
waters can be removed at a loading of 0.25 Ibs BOD5/day/lb MLVSS with
approximately a 90 percent BOD5 removal at loadings up to 0.70 Ibs BOD^/day/
Ib MLVSS. These data were obtained using bench scale biological reactors.
5. It is anticipated that approximately 36,000 Ibs/day of biological synthesis
sludge and 144,000 Ibs/day of primary sludge will be generated when the full-
scale treatment system is put into operation.
6. The bench scale studies indicate that approximately 1,800 Ibs of oxygen/
day/MG are required for an aerobic activated sludge system.
7. Based on laboratory analyses, fecal organisms observed in the raw industrial
wastewaters appeared to be sufficiently destroyed as to not require disinfection.
These studies indicate chlorination of the final effluent from a treatment system
receiving wastewaters as presently constituted is not required. Coliform analyses
conducted during the pilot plant phase of this study confirmed these results.
8. The effectiveness of removing pollutants from biologically treated effluent
using carbon adsorption was evaluated by undertaking batch carbon adsorption
isotherm tests. These studies indicated that most of the soluble BOD remaining
after biological treatment was removed with an activated carbon dose of less than
40 mg/l. The removal of color to trace levels required carbon concentrations
slightly in excess of 200 mg/l. While batch isotherm studies are "screening
tests" only, they are indicative of carbon removal capacities and thus establish
8
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a basis for subsequent continuous column studies.
Pilot Plant Treatability Studies
1. The hydraulic mixing characteristics for the 50 gpm capacity pilot plant
facility were established using dye studies. The results for the equalization tank
indicate that adequate mixing and circulation are achieved by using a high
capacity recycle pump. The data indicate that only 23 percent of the tank was
unused, with the remaining volume exhibiting completely mixed characteristics.
Neutralization and aeration tanks were completely mixed. The primary and
secondary clarifier flow patterns were found to be adequate after subsequent
modifications were made.
2. The oxygenation capacity of the mechanical and diffused aeration systems
in the aeration tanks of the pilot plant were determined. A transfer efficiency of
2.90 Ibs of oxygen/HP-hr for the mechanical aeration system was noted and tin
efficiency of 1.15 Ibs of oxygen/HP-hr was observed for the diffused aeratjion
system. These results are reflected in the process design formulation.
3. A computer program was developed to perform the necessary mathematical
operations of the biological treatment results and resolve the data into design
parameters and coefficients with an interpretation of the statistical reliability
of each parameter.
4. The biological pilot plant studies indicate that approximately 65 percent of
the COD and 90 percent of the BOD5 can be effectively removed by this process
except during periods of extremely cold weather. A minimum BODg removal of
66 percent is predicted during the coldest period of the year based on a temperature
balance calculated across the aeration basins. As this balance was made utilizing
observed inlet temperatures to the aeration basin of the pilot plant, slightly
higher removal efficiencies could be expected in the full scale plant based on a
comparison of heat losses calculated for both the pilot plant and the regional
facility.
5. The transient loading studies conducted during both the summer and winter
operations indicate that there is little or no effect on the performance of the
biological system due to variations in the organic characteristics of the combined
wastewaters. Equalization at the regional treatment site, therefore, is not
recommended based on these results.
6. The process design criteria for the biological system were formulated based on
the computer resolved design parameters and coefficients. These basic criteria
include a required aeration detention time of 12 hours, an oxygen utilization
rate of approximately 155,000 Ibs/day and a biological sludge production rate of
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36,000 Ibs/day with a hydraulic design flow rate of 72 MGD.
7. The pilot plant performed efficiently in the removal of organic contaminants
from the combined wastewaters. However, there were occasional problems
encountered during the operations which should be considered in the full-scale
treatment design. For example, the pH monitoring probes required cleaning;
foaming occurred occasionally in the aeration basins and was excessive at times;
exposed carbon steel appurtenances on the upstream side of the neutralization
facility were subject to extensive corrosion; and occasional power shutdowns
temporarily interrupted operations. The experience gained from the pilot plant
operations is considered invaluable in the translation of these studies to full-scale
design and implementation of wastewater management practices.
8. Aerobic digestion provides a maximum of 50 percent reduction in volatile
suspended solids (VSS) with a retention period of 20 days. A retention time of
seven days is sufficient to achieve 75 percent reduction of the digestible solids
provided the reactor has facilities for continuous withdrawal of sludge liquor and
subsequent thickening of the residual sludges. Mixing will control requirements
for an aerobic digester.
9. The effectiveness of the filter press, vacuum filter and centrifuge for de-
watering primary and digested sludges was evaluated using pilot scale models.
These process simulation studies indicate that filter press or vacuum filtration
dewatering would be the most applicable processes when considering land fill
as the ultimate disposal of the sludges. Filter press dewatering of the combined
primary and excess biological sludges was used for the process design calculation
and cost estimates.
10. Continuous flow bench and pilot scale carbon column studies indicate that
carbon adsorption is effective in removing color, residual organics, and toxic
substances from the biologically treated effluent throughout the operational year.
However, the data suggest that carbon adsorption is more effective as a tertiary
process following biological treatment than as a total process. This observation
is predicated on the fact that a high leakage of BOD was noted when the un-
treated wastewater was applied directly to the carbon columns. This can be
attributed to the presence of certain organic constituents which are biodegradable
but not amenable to adsorption.
11. The addition of powdered activated carbon to the activated sludge process
was investigated. Although improved organic removal was observed, the sludge
handling phase including powdered carbon regeneration has not been sufficiently
developed to allow a forceful recommendation of this process.
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12. Effluent polishing processes including sand filtration and microstraining
were investigated. On the basis of effluent quality criteria, the use of either
of these processes as polishing processes is not recommended.
Effluent Quality Analysis
1. The predicted effluent quality of the proposed treatment facility as presented
in this report will meet the DRBC standards as adopted on 7 March 1968, and as
amended through March 26, 1970.
2. It is recognized that the effluent quality projection as presented in this report
is based on the treatability of the combined wastewater having the quality
characteristics observed during this study. However, the period of time over which
the treated and untreated wastewaters were characterized affords statistical
creditability. The effluent quality as predicted is therefore sufficiently accurate
to justify implementation of the recommended system which has the capacity and
capability to treat wastewaters of a similar nature to this required quality level.
RECOMMENDATIONS
Based on the conclusions as stated herein, and the detailed investigations which
are documented in this report, the following recommendations are made concerning
the major treatment processes for the regional treatment system.
1 o It is recommended that the major treatment processes for the regional treatment
system, based on economic considerations, process applicability and effluent
quality standards, include an activated sludge system followed by an activated
carbon effluent polishing system. Recommended pretreatment processes include
neutralization and primary clarification. Additionally, aerobic digestion and
filter press dewatering are recommended to handle the primary and wasted
activated sludges.
Specific recommendations pertaining to the individual treatment processes are as
follows:
a. It is recommended that the neutralization system includes a premixing
basin prior to a series of four, two-stage neutralization basins, each
stage having a residence time of fifteen minutes. Dolomitic lime is
recommended as the neutralization agent based upon economic
considerations.
b. It is recommended that the primary clarification system includes twelve
parallel basins equipped with mechanical sludge removal mechanisms.
Each basin would be sized for a maximum overflow rate of 800 gal/day/
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c.
ft* with a minimum residence time of two hours.
It is recommended that the secondary biological system include six
completely mixed, parallel aeration basins each having a residence
time of twelve hours. Ten - 100 HP, pier mounted, surface aerators
are recommended for each basin to provide for adequate mixing and
oxygenation. Final clarification will be accomplished by twelve,
parallel, center-fed, 110 ft. diameter circular clarifiers.
d. It is recommended that the activated carbon effluent polishing system
include twenty, two stage parallel adsorbers having a total residence
time of 20 minutes. Activated carbon regeneration, storage and
conveyance appurtenances should be sized to handle a carbon exhaust-
ion rate of 283,300 Ibs/day.
e. It is recommended that the wasted activated sludge be aerobically
digested, combined with the primary sludge, gravity thickened and then
dewatered by the filter press process. Ultimate sludge disposal by land
fill is recommended as this is currently the most acceptable method.
(Reference Interim Pilot Plant Report, Chapter VII).
2. It is recommended that a 72 MGD treatment facility, conceptually designed
as described within this text, be implemented to serve the industries and
municipalities in the lower Delaware River Basin. The estimated capital cost of
the regional facility is $39,957,000(ENR=1400). The estimated annual operation
and maintenance cost is $2,965,000 and the total annual cost is estimated to be
$5,829,000. While it is recognized that a higher ENR value would be applicable,
1400 is used to be consistent with previously submitted cost estimates.
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SECTION III
INTRODUCTION
GENERAL
This final pilot plant report summarizes the results of the entire pilot plant testing
program. This compilation is intended to complement the final report, "Deepwater.
Regional Sewerage System Preliminary Engineering and Feasibility Study," presented
by Engineering-Science, Inc., to the Delaware River Basin Commission, June, 1970.
This project was supported in part by the United States Government, Environmental
Protection Agency, Research and Development Grant 11060-DR0. Where that
report presented the aspects related to the Interceptor Preliminary Engineering Study
system cost estimates and cost apportionment plans, the information presented herein
relates to the "treatment phase" of the overall project. These data represent the
accumulation of approximately 30 months of treatment studies, including the
purification of wastewaters emanating from the participating industries and munici-
palities, the handling of resultant wastewater sludges, and an evaluation of
applicable wastewater treatment and handling systems, using both bench scale
and pilot scale unit procedural techniques.
The use of 6 combination of unit processes, which must be properly integrated in
order to constitute an efficient waste treatment system, depends on many factors.
A "treatability" evaluation, therefore, must consider and properly define these
factors in order to effectively translate the data as presented into a basis for
establishing an optimal treatment system. The presentation of treatment information,
its interpretation, and its resolution to design information is therefore consistent
with the goals of conceptualizing and developing a wastewater treatment complex
capable of producing an effluent with a quality which meets the criteria as
established by the regulatory authority.
SCOPE OF THE STUDY
The scope of the Deepwater Pilot Plant Study generally conforms with that outlined
in the "P Task" section of the proposal for the Deepwater Pilot Plant Engineering
and Interceptor Preliminary Engineering Study submitted to the Delaware River
Basin Commission by Engineering-Science, Inc., in February, 1969, and incorpora-
ted into the contract between the aforementioned parties in July, 1969. However,
there are many ancillary studies both with respect to treatment of liquid wastewaters
and handling of sludges, which were not included in the original scope but which
were considered necessary in order to fully complement the treatment evaluation
program.
As defined in the original proposal presented by Engineering-Science, Inc., the
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project was subdivided into a series of individual and identifiable Tasks. The
identification of these Tasks, properly sequenced, is illustrated in the Activity
Plan as originally presented, Figure I. The implementation of these various
tasks generally follows the format originally established. This Task delineation
of project requirements can be summarized as follows:
Task P-1 — Preliminary Design of Pilot Plant Characteristics
This Task includes a comprehensive wastewater collection and characterization
program, bench scale biological treatability studies both on the individual
wastewaters and the composite, an evaluation of the related physical and chemical
characteristscs of the biological system, and ancillary bench scale studies necessary
for overall system evaluation.
Task P-2 — Define Pilot Treatment Plant Programs
This Task involves the comprehensive review of Task P-1, as well as other inputs,
all related to properly defining the pilot treatment plant program. Alternative
pilot treatment systems were considered, methods for properly collecting and
analyzing data were delineated and operational flexibility requirements were
defined.
Task P-3 — Design Pilot Treatment Plant
Based on preliminary information collected in Task P-1 and elsewhere, the final
pilot treatment plant design drawings and specifications were formulated.
Task P-4 — Construct Pilot Treatment Plant
Once the design drawings and specifications were reviewed and approved, the
Deepwater Pilot Plant, which was designed hydraulically rf 50 gallons per
minute, was constructed. This construction included wastewater receiving
facilities, storage tanks, neutralization, biological oxidation processes, final
clarification, and chemical treatment facilities. All of the piping, control
valves, sample collection devices, and process safeguard appurtenances were
included in order to insure that the pilot system would be capable of meeting
project objectives.
Task P-5 — Evaluate Unit Processes of Pilot Treatment Plant
The physical, hydraulic and oxygenation characteristics of the pilot plant
facility were established in this Task effort.
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Ol
Note''.?" Toiki Refer to (tie
Deepwater Pilot Plant Study.
ACTIVITY PLAN
PILOT PLANT PRELIMINARY
ENGINEERING STUDY
(Q
i
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Task P-6 — Define Feasible Alternative Treatment- Systems
The feasible alternative treatment systems based on the waste'water characteri-
zation per present technology and economics were assessed in this Task write-up.
Task P-7 — Conduct Pilot Treatment Plant Studies
The responses of the biological system to operating and environmental variables
were assessed during the performance of this Task. Additionally, ancillary
biological, chemical and physical tests were undertaken in order to establish a
basis for the formulation of final design criteria for the regional treatment
facility.
Task P-8 — Recommend Wastewater Treatment System
Additional modes of treatment were considered in order to establish the relative
feasibility of using conventional biological processes. Carbon adsorption and
chemical treatment were considered both in terms of individual systems or as
supplementary steps to the biological phase of treatment.
Task P-9 -- Establish Final Design Criteria for Regional Treatment Plant
Based on a comprehensive review of the "P Tasks" up to and including P-8,
general guidelines for selecting and sizing unit processes within an overall
treatment complex were set forth.
Task P-10 — Prepare Preliminary Regional Facility Design & Cost Estimates
This Task included the formulation of the general treatment plant design and the
resultant cost estimates.
Task P-11 -- Conduct Detailed Pilot Treatment Plant Studies
Following completion of the previously outlined pilot studies, additional tests
considering a refined treatment approach using the existing pilot system were
undertaken. This included a more thorough study of sludge handling and disposal
and liquid effluent polishing.
Task P-12 — Prepare Final Report on Pilot Treatment Plant Study
This final report is submitted to the Delaware River Basin Commission and includes
the entire spectrum of previously discussed studies. The submission of this final
report constitutes the terminal phase of the project, the timing of which is in
accordance with that outlined in the Activity Plan, Figure I.
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ORGANIZATION OF THE STUDY
In order to effectively implement the Tasks associated with the bench and pilot
scale treatability program, key personnel including engineers, chemists, and
management specialists were selected. This team then directed their entire efforts
toward the realization of the project objectives.
A special office was established by Engineering-Science, Inc. at the pilot plant
site located on the Chambers Works Plant, E. I. duPont de Nemours Company,
Deepwater, New Jersey. The field supervision of the wastewater collection
program, bench scale treatability studies, pilot plant construction and operations,
and data assimilation and processing was conducted from this office.
Overall project management for the wastewater treatment phase of this project was
provided by Eugene J. Kazmierczak, President of Engineering-Science, Inc.,
and Dr. Harvey F. Ludwig, Chairman of the Board. Dr. Davis L. Ford was the
Project Engineer assisted by Resident Engineers Fred J. Fahlen and S. Dave Ellison.
Staff engineers who provided valuable assistance to this project include Dr. Jan
Scherfig, Nicholas L. Presecan, Larry Tropea, James M. Eller, Billy A. Carnes,
Richard W. Bentwood, and Douglas M. Darden.
The analytical work associated with this project, including organic analyses,
bacteriological testing, and ancillary chemical, physical, and biological analyses
were conducted by contractual arrangement between Engineering-Science, Inc., and
duPont. Trucking of the various wastewaters to the pilot plant holding tanks was
undertaken by Chemical Leaman, Inc., and the daily operational and maintenance
duties were relegated to duPont personnel, all according to agreements with and
under the supervision of Engineering-Science project management.
Special Consultants to Engineering-Science, Inc.
•
The consultants which provided special input to the design and implementation
of the pilot plant program are eminently qualified in the field of wastewater
treatment and water quality management. They are:
(1) Dr. Earnest F. Gloyna, Dean, College of Engineering, The University
of Texas at Austin, Austin, Texas, and;
(2) Dr. ErmanA. Pearson, Professor of Sanitary Engineering, University of
California at Berkeley, Berkeley, California.
Coordination and Liason
Dr. Leon Weinberger, former Assistant Commissioner of the Federal Water Quality
Administration, and Dr. Gordon McCallum, former Assistant Surgeon General,
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U. S. Public Health Service, both of the Washington, D. C. office of Engineer-
ing-Science, served in the capacity of providing the necessary liason with the
Environmental Protection Agency in Washington, D. C.
Delaware River Basin Commission Staff
The project implementation was continuously coordinated with the Delaware River
Basin Commission Staff including the following: James F. Wright, Executive
Director; Herbert A. Hewlett, Chief Engineer; Ralph Porges, Head, Water Quality
Branch; Paul Webber, Supervisor of the Deepwater Project; and Arthur E. Peeck,
Chief Administrative Officer. This coordination was necessary in order to insure
that Task development and implementation were commensurate with the general
project goals and water quality objectives established by the Commission.
Technical Advisory Committee
Each participating industry and municipality had representation on the Technical
Advisory Committee and this consortium provided valuable assistance and
guidance throughout the conduct of the Project. Mr. W. H. Roach of Texaco,
Inc., served capably as Chairman of this committee until his retirement from
Texaco. Mr. Charles A. Evans of the duPont Chambers Works Plant succeeded
him as Chairman. Mr. Robert Kausch has ably served as secretary of all Technical
Advisory Committee meetings. Monthly meetings were held by the TAC in order to
provide a forum for submitting progress reports, exchanging ideas, and insuring
liason between all of the attendant groups.
Executive Committee
>
Mr. Herbert A. Hewlett, Chief Engineer of the Delaware River Basin Commission,
and Dr. Harvey F. Ludwig, Chairman of the Board, Engineering-Science, Inc.,
assisted by their staff consultants, have reviewed the treatability phase of the
project, and in concert with Mr. James F. Wright, have made recommendations
relative to its effective implementation.
Acknowledgements
There are many entities and individuals who have made significant contributions
to the technical and managerial facets of this Project. Those organizations
and individuals previously mentioned deserve special credit as well as the
Environmental Protection Agency, the Department of Environmental Protection
of the State of New Jersey, and the Delaware River Port Authority. Particular
appreciation is expressed to industrial and municipal representatives who assisted
Engineering-Science personnel in resolving the complex logistics involved with
collecting representative wastewater samples from the many points of discharge
within the study area.
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SECTION IV
WASTEWATER CHARACTERIZATION
The first step in developing a rational basis for designing wastewater treatment
facilities is the determination of the wastewater characteristics, both quantita-
tively and qualitatively. This is particularly complex when considering the
variable flow and constituents inherent with the operations of both the participating
municipalities and industries. Because of this variation, it is necessary to obtain
sufficient characterization data to have statistical significance. Moreover, it is
necessary not only to define existing quantities of pollutants but also to project
pollutant levels which could be anticipated throughout the life of the treatment
facility.
The present and projected industrial wastewater quantities established for purposes
of designing a regional treatment facility in the Deepwater Region have been
cited previously. However, a more complete tabulation of wastewater characteri-
zation data collected during the bench scale and pilot scale phases of this
Project are presented herein.
The characterization schedule included those parameters considered meaningful
with respect to wastewater definition, treatability, and effluent quality require-
ments. Because of the volume of data accumulated during the course of this
study, only pertinent statistical results are reported in this Chapter. Additional
information - such as sample collection procedures, data correlation and inter-
pretation, and ancillary parametric definition - is also included.
DESCRIPTION OF THE SAMPLING PROGRAM
Sampling programs were established at all the industrial sites in the Study Area for
the bench scale phase of the study, with the exception of the B. F. Goodrich
Plant which was under construction. Prior to the initiation of the sampling programs,
in-plant surveys were made at each industry to determine the layout of the waste-
water systems and to select sampling points where the most representative samples
could be obtained. Sampling schedules were then initiated at each individual
plant depending on the type of sampling equipment utilized and the sample fre-
quency required to obtain the composites. Each composite was then collected
for analysis and transported to the laboratory .
Sampling programs at five municipal treatment plants in the Study Area were
established on a 24-hour composite basis with three composites taken on Tuesday,
Thursday, and Saturday. Municipal treatment plants sampled included Pennsville
Sewerage System, Salem City, Upper Penns Neck, Woodbury, and Paulsboro.
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A description of the wastewater facilities at each of the industries, the sampling
sites, and the sampling programs that were established are described below:
Industry; Texaco, Inc.
Treatment Facilities
The treatment facilities at Texaco consist of a collection system that discharges
into an API oil separator. The effluent from the separator flows to a surface
discharge point, over a five foot rectangular weir, and into the Delaware River.
All process wastewater, cooling tower blowdown, boiler blowdown, process
area runoff and ballast water from incoming ships flow via the collection system
to the oil separator.
Sampling Site and Equipment
The economics of oil recovery through the separator dictates oil separation prior
to the discharge of the wastewater. Therefore, the proposed discharge to the
regional system would, be the effluent from the oil separator. A sampling point
was established at the separator outfall.
The sampling equipment consisted of a gas-operated liquid sampler (Protec Model).
This instrument was set so that a series of 50 ml samples, taken at specific time
intervals, would give a sample volume of 22 liters over each 24-hour composite
period. This type of compositing is considered satisfactory because the flow from
the continuous refining process is relatively constant.
Sampling Program
Twenty-four hour composites were taken every other 24-hour period so that
within a two-week sampling period, each day of the week was represented .
Industry; Shell Chemical Co.
Treatment Facilities
The treatment facilities at Shell consist of a neutralization chamber, floatable
solids separation tank and a lift station-force main system that delivers the
effluent to the Delaware River. There are three separate collection systems
within the plant. Two systems flow directly to the neutralization chamber,
one conveying the septic tank overflow, cooling tower blowdown and some
process wastes and the other conveying the effluent from the alcohol recovery
unit. The third system is the surface runoff collection sewer which empites into
Mantua Creek without treatment „
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Sampling Site and Equipment
The effluent from the process area contains floatable plastic fines and therefore,
the proposed effluent to the regional system would be the effluent from the
floatable solids separation tank. The sampling point was established at the out-
fall of the solids separation tank.
The sampling equipment consisted of a Protec Model, gas-operated, liquid
sampler. This instrument was set so that a series of 50 ml samples, taken at specific
time intervals, would give a sample volume of 22 liters over each 24-hour composite
period. This type of compositing was considered satisfactory because the flow from
the polypropylene process is relatively constant.
Sampling Program
Twenty-four hour composites were taken every other 24-hour period so that over
a two-week period, each day of the week was sampled.
Industry; Mobil Oil Corporation
Treatment Facilities
The treatment facilities at Mobil consist of three separate discharge systems—the
North Pond, the Channelized Pond, and the Commissioner's Ditch. Each of the
systems has some type of oil separation and skimming equipment installed. All
process water, once-through cooling water, cooling tower blowdown, boiler
blowdown, surface runoff and ballast water from incoming ships discharge through
one or more of the three systems. All the systems discharge directly to the
Delaware River following oil separation.
*
Sampling Site and Equipment
During the sampling program, flows were not measured at any of the three outfall
systems. For this reason, separate composite samples were taken at each of the
three outfalls and then combined to make up a total composite based on flow*
estimated by Mobil personnel.
North Pond; The sampling point at the North Pond was at the outfall
structure. A Protec Model sampler was employed at this point.
Channelized Pond; The sampling point was at the outfall structure using a
Protec Model sampler.
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Commissioner's Ditch: The elevation of the outfall structure at Commissioner's
Ditch is such that discharges occur only at low tides. For this reason, a
composite sampler was utilized at this point in which one-hour composites
were obtained continuously and then composited based on tidal time charts.
Sampling Program
Twenty-four hour composites were taken once a week at each of the outfall systems.
This type of sampling program was necessitated because of the absence of reliable
flow data and the exigency of scheduling samplers. Additional data was supplied
by another consultant conducting an in-plant survey for Mobil.
Industry; Houdry Process and Chemical Co.
Treatment Facilities
The treatment facilities at Houdry consist of two separate systems, the once-
through cooling water system and the organic wastewater system. Two separate
lift stations pump the waste streams to a common manhole on Mobil property.
The combined waste then outfalls to a surface ditch leading off of Mobil property
to the Delaware River. Included in the organic wastewater system is the septic
tank overflow and cooling tower blowdown.
Sampling Sites and Equipment
Since there are two waste systems, two sampling sites were selected, each at
their respective lift station. In both cases, sampling cocks on the discharge side
of the pumps were connected to collection containers. When the pumps were
operating, a steady stream of waste entered the containers. Composite samples,
therefore, were obtained according to flows. Samples collected at the once-
through cooling water lift station were analyzed separately to determine if any
outside contamination was present.
Sampling Program
Twenty-four hour composites of both streams were taken initially. After several
analyses of the cooling water waste, only grab samples were taken. Composites
on the organic waste stream were continued at a frequency of three per week.
Industry: Hercules, Inc.
Treatment Facilities
The treatment facilities at Hercules consist of neutralization, equalization,
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extended aeration, clarification and chlorination. The outfall from the chlorine
contact tank is routed directly to the Delaware River. Included within the waste-
water stream is some process area surface runoff. A separate, highly concentrated
waste consisting of spent sodium carbonate is incinerated in a thermal oxidizer
unit.
Sampling Equipment and Site
A sampling site was established at the neutralization facility. This facility is
well mixed and acts as a wet well for the lift station which pumps the waste to
the biological treatment facilities. Samples were taken from a sampling cock
on the discharge side of the lift pump and composited in a 55 gallon drum over a
24-hour period.
A second sampling point was established at the thermal oxidizer unit as this
waste might be discharged into the regional system. A sampling cock on the
discharge side of the recirculation pump at the feed storage tank was employed
to obtain grab samples.
Sampling Program
Twenty-four hour composites of the organic waste stream were collected every
other 24-hour period. Grab samples of the waste discharged to the thermal
oxidizer were taken at various intervals to establish the organic strength of the
waste.
Industry; duPont-Repauno Works
Treatment Facilities
The present facilities at Repauno consist of an open ditch system that collects all
the cooling water and organic waste streams. The waste is discharged directly
into the Delaware River after neutralization and floatable solids separation.
Sampling Sites and Equipment
The waste segregation program within the Repauno Plant was not yet completed
and therefore composites were taken manually from the three concentrated
organic streams. Composites were based on the future waste segregation estimates.
Sampling Program
Composite samples were obtained three times per week.
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I nd ustry; Mo nsa nto C o.
Treatment1 Facilities
The facilities at Monsanto consist of a lift station-force main system which outfalls
directly to the Delaware River, All surface runoff is conveyed to the Delaware
River via a separate system.
Sampling Site and Equipment
The sampling site selected at Monsanto was at the lift station and was the only place
where a composite could be conveniently taken. A composite sampler was utilized
such that a composite was collected every eight hours with a total composite made
manually over a three-day collection period.
Sampling Program
Samples were composited three times a week; two of these composite samples were
three-day composites and one sample was a one-day composite.
Industry; duPont -Carney's Point
Treatment Facilities
The facilities at Carney's Point consist of a lift station-force main system which
discharges waste directly to the Delaware River. Most of the plant's aqueous
waste is carried through this system.
Sampling Site and Equipment
The sampling site at Carney's Point was at the lift station and consists of an air-
operated valve assembly on the discharge side of the lift pumps. The samples
were composited in a stainless steel 55 gallon drum.
Sampling Program
Composite samples were obtained three times a week and depending on the pick-up
date were either two or three-day composites.
Industry; duPont - Chambers Works
Treatment Facilities
The waste treatment facilities at the Chambers Works consist of a ditch system
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that outfalls into a sedimentation basin. The waste is then neutralized and pumped
to the Delaware River.
Sampling Sites and Equipment
The waste segregation program had not been fully completed at the Chambers Works
at the time of sampling . Therefore, composites of various organic streams were
based on estimated waste discharges after the segregation program was completed.
Sampling Program
Composites of the projected waste streams were made daily.
The mode of sample pick-up for the Pilot Plant phase of the Project was varied
from the sampling program previously described because of the daily wastewater
volume requirement and the logistical problems involved. Although the sampling
locations remained the same, industrial and municipal wastewater samples were
collected from the participants and conveyed to the pilot plant site in 5,600
gallon capacity tank trucks. This, in effect, represents a "grab" rather than a
"composite" approach in obtaining the samples. It should be recognized,
however, that these samples were collected a minimum of twice weekly from each
participant over a period of twelve months, which would imply a statistical
significance.
WASTEWATER CHARACTERIZATION AND FLOW
The characterization of wastewaters received from the participants during all
phases of this program and the respective volumes of flow are summarized herein.
Quantity
The samples collected from each industrial participant were composited according to
stated design flows and subsequently pumped to the bench scale units. No municipal
wastes were included in this phase of the investigation because of their minor
contribution to the total input, both in terms of hydraulic and organic loading. The
contributing percentages of flow were slightly altered when the pilot plant studies
commenced because of an updating of effluent discharge volumes obtained from the
participants. The basis for compositing participant wastewater contributions for the
bench scale studies and the revised formula for equalizing the contributions for the
pilot plant study are summarized in Table I. The flow distribution is stated in terms
of estimated 1975 values.
Quality
Detailed analyses of the industrial wastewaters were begun as soon as the
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sampling systems were installed at the individual plant sites. The analytical
program for the integrated industrial waste sample was begun after all sampling
systems were completed and the estimated flows for 1975 had been received.
Initially, 24-hour composite samples from each plant were analyzed approximately
three times a week.
The integrated sample was analyzed once a week, and this schedule was continued
until the pilot pbnt was operating on the integrated waste stream. At that time,
the Task P-l, or bench scale, analytical program was replaced by the pilot plant
evaluation program.
Analyses were also performed on five separate municipal wastewaters.
Three 24-hour composite samples were collected at each of the following plants
and analyzed for the same constituents as the industrial wastewaters: Pennsville,
Salem City, Upper Penns Neck, Woodbury, and Paulsboro. These characterization
data are reported in Chapter V of the Final Preliminary Engineering and Feasibility
Study submitted by Engineering-Science in June, 1970.
Procedures
The analyses performed on the individual samples and the methods used are as
follows:
1. pH was measured with a Leeds and Northrup pH meter.
2. Alkalinity, acidity and neutralization determinations were made with a
Fisher Automatic Tritrimeter with 0.02 N sodium hydroxide or 0.02 N
sulfuric acid.
3. Chemical oxygen demand (COD) was measured in accordance with
Standard Methods using the 10.0 ml alternate procedure.
4. Biochemical oxygen demand (BOD) was determined in accordance with
Standard Methods using seed acclimatized to the individual industrial
wastewaters.
5. Dissolved oxygen was measured with a Weston-Stack D.O. meter.
The meter was calibrated daily using the Winkler Method.
6. Nitrate and nitrite determinations were made with a Technicon Auto-
analyzer in accordance with the Technicon Manual.
7. Total Kjeldahl nitrogen was measured with a Technicon Auto-analyzer
in accordance with the Technicon Manual.
26
-------
8. Total phosphorus was measured in accordance with Standard Methods.
9. Phenol was measured in accordance with Standard Methods except that
a 100 ml sample was distilled instead of 500 ml.
10. All solids measurements were in accordance with Standard Methods.
11. Methylene Blue Active Substances (MBAS) were measured in accordance
with the Water and Sewage Analysis Methods Manual, Hach Chemical
Company, using the methyl green procedure.
12. All heavy metals were measured using a Perkin-Elmer Atomic Absorption
Spectrophotometer Model 303.
13. Total organic carbon (TOC) was measured with a Beckman Model 915
Total Organic Carbon Analyzer.
14. Color determinations were made with a color comparator in accordance
with Standard Methods, 12 Edition (1965).
Data Handling and Output
Raw data were transferred from laboratory work sheets to standardized data sheets,
with each sample identified only by a three digit code and the date. From the
standardized sheets, the data were transferred to computer cards, and then read
and stored on discs by an IBM 360 Computer.
The output from the computer consisted of the following for each individual
wastewater: one sheet presenting all data to date and summarizing each constituent
in terms of high value, low value, average, and the standard deviation based on
N observations; a second sheet with the ratios BOD5: COD, BOD5: TOD, TOC:
COD; a third sheet summarizing flow data.
Results
The computer output sheets are not included in this report and are tabulated
separately as task reports because of the bulk of information accumulated during
this project. However, a statistical water quality representation of the samples
received from each participant during the bench scale phase of the project is
tabulated in Table 2. A similar presentation of the quality data observed during
the pilot plant studies is given in Table 3. The characteristics of the combined
industrial and municipal samples used in the bench scale phase are summarized in
Table 4. The combined characterization data of the wastewaters applied to the
pilot plant, effectively representing the quality of water which would have to be
27
-------
TABLE 1
PARTICIPANT WASTEWATER FLOWS
CO
00
PARTICIPANT
duPont -
Chambers Works
Mobil
Texaco
Shell
Monsanto
duPont -
Carney's Point
Goodrich
duPont - Repauno
Houdry
Hercules
Municipalities
Five-Year
Projected
Flow (MGD)*
38.60
26.00
8.60
3.00
3.00
2.40
1.20
1.10
0.30
0.14
3.50
Percent
Contribution
43.90
29.60
9.70
3.40
3.40
2.70
1.40
1.30
0.40
0.20
4.00
Revised
Five-Year
Flow (MGD)**
45.21
14.00
6.80
3.00
3.25
S-JB
•1.30
0.25
0.25
0.16
5.57
Revised
Percent
Contribution
54.50
16.87
8.20
3.61
3.92
3.83
1.57
0.30
0.30
0.20
6.70
87.84 MGD 100.00%
* Basis for conducting bench scale studies.
** Basis for conducting pilot plant studies.
82.97 MGD 100.00%
-------
TABLE 2(A)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 015*
PARAMETER
PH
TDS,mg/l
VDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**.
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
10.6
42,570
9,440
560
70
28 ,000
13,200
7,175
30.0
5.0
5,250.0
12,2
0.6
0.3
6.8
0.9
1.8
0.6
LOW
8.3
15,760
800
10
0.01
7,600
2,108
2,411
2.5
0.3
800.0
4.8
0.2
< 0.1
< 0.1
< 0.1
0.2
< 0.1
MEAN
9.4
23,497
3,154
80
31
14,977
7,463
4,656
14.0
1.8
2,187.5
8.5
0.4
< 0.2
< 0.35
< 0.4
0.5
< 0.2
STD.
DEV.
0.7
6,792
2,513
125
17
5,542
2,655
1,465
7.5
1.1
1,188.7
3.7
0.1
-
-
-
0.4
-
COEF. OF
VAR.
0.07
0.30
0.80
1.54
0.55
0.37
0.36
0.31
0.54
0.61
0.54
0.44
0.25
-
f—
-
0.80
-
# OF
OBS.
16
18
17
17
16
18
18
16
17
17
12
2
18
18
18
18
18
18
* Composited samples
** Sensitivity of analysis = 0.1 mg/1
29
-------
TABLE 2(B)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 025*
PARAMETER
PH
TDS, mg/1
VDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
9.6
2,860
1,500
140
120
930
98
156
34.0
32.0
6.8
3.8
1.1
< 0.1
3.2
0.7
1.6
1.1
LOW
2.7
210
80
1
1
107
16
21
1.0
0.1
0,0
0.4
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0,1
MEAN
7.0
920
386
31
23
238
57
48
16.5
3.6
1,6
1.2
< 0.3
< 0.1
< 1.0
< 0.2
< 0.3
< 0.2
STD.
DEV.
4.4
599
286
32
26
146
20
30
8.3
7.1
1.8
1.3
-
-
-
-
-
-
COEF. OF
VAR.
0.63
0.65
0.74
1.03
1.13
0.61
0.35
0.62
0.50
1.97
1.13
1.08
-
-
-
-
-
-
# OF
OBS.
21
26
26
24
24
32
24
26
24
25
21
5
24
24
24
24
24
24
* Composited samples
** Sensitivity of analysis =0.1 mg/1
30
-------
TABLE 2 (C)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 035*
PARAMETER
pH
TDS, mg/1
VDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
8.6
1,110
520
60
60
461
110
116
40.0
2.6
7.9
40.5
0.3
< 0.1
1.9
0.2
3.5
0.4
LOW
3.3
340
1
1
1
203
47
11
3.2
0.3
0.0
5.1
< 0.1
< 0.1
0,2
< 0,1
< 0.1
< 0.1
MEAN
6.5
700
209
38
27
290
66
52
21.2
1.0
2.8
15.5
< 0.2
< 0.1
0.6
< 0.1
< 0.5
< 0.2
STD.
DEV,
1.7
212
131
19
19
101
17
39
12.6
0.6
2.8
12.8
-
-
-
-
-
-
COEF. OF
VAR.
0.26
0.30
0.63
0.50
0.70
0.35
0.26
0.75
0.59
0.60
1.0
0.83
-
*—
-
-
-
-
# OF
OBS.
10
12
12
11
11
12
10
10
10
11
9
5
11
11
11
11
11
11
* Composited samples
** Sensitivity of analysis =0.1 mg/1
31
-------
TABLE 2(0)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 045*
PARAMETER
PH
IDS, mg/1
YDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
4.2
3,750
1,320
120
90
927
300
233
39.0
55.0
6,9
9,5
3.5
1.1
5.0
0.5
1.0
5.8
LOW
2.0
1,500
30
1
1
251
41
79
1.0
0.3
1.0
4.6
< 0.1
0.3
2.3
< 0.1
< 0.1
0.8
MEAN
2.7
2,446
769
54
32
495
181
133
17.8
8.6
4.1
6.3
< 1.1
0.6
3.6
< 0.2
< 0.5
2.3
STD.
DEV.
0.5
752
354
38
27
176
60
39
11.4
11.6
1.5
2.3
-
0.2
0.8
-
-
1.5
COEF. OF
VAR.
0.18
0.31
0.46
0.70
0.84
0.36
0.33
0.29
0.64
1.35
0.37
0.37
-
0.33
0.22
-
-
0.65
t OF
OBS.
20
19
19
18
18
20
18
20
14
19
10
3
12
12
12
12
12
12
* Composited samples
** Sensitivity of analysis
0.1 mg/1
32
-------
TABLE 2(E)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 065*
PARAMETER
PH
TDS, mg/1
YDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOG, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/l**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH.
2.6
4,600
1,720
200
180
1,788
780
480
38.0
2.0
25.0
4.8
0.6
0.3
45.0
0.8
0.9
1.2
LOW
1.2
1,980
1,080
1
1
392
120
129
0.8
0.0
0.0
0.2
< 0,1
< 0.1
3.8
< 0.1
< 0.1
0.2
MEAN
1.9
3,423
1,327
60
53
767
329
238 ^
8.3
0.6
3.7
1.7
< 0,2
< 0.1
8.1
< 0.2
< 0.2
0.4
STD.
DEV.
0.4
1,086
281
81
74
319
140
98
9.6
0.4
8.7
2.2
-
-
9.1
-
-
0.2
COEF. OF
VAR.
0.21
0.32
0.21
1.35
1.40
0.42
0.43
0.41
1.16
0.67
2.34
1.29
-
-
1.12
-
-
0.50
# OF
OBS.
22
3
3
4
4
23
22
20
23
23
7
3
18
18
18
18
18
18
* Composited samples
** Sensitivity of analysis =0.1 mg/1
33
-------
TABLE 2(F)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 075*
PARAMETER
pH
TDS, mg/1
VDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
11.4
5,680
1,970
3,130
36Q
154
69
68
1,250.0
92.8
2.9
1.3
0.4
< 0.1
1.2
0.2
0,9
0.3
LOW
2.7
190
j
110
20
1
39
3
4
0.7
0.3
0.0
0.2
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
MEAN
8.7
1,446
623
312
56
88
14
30
194.5
7.1
0.5
0.7
< 0.1
< 0.1
< 0.2
< 0.1
< 0.2
< 0.1
-. STD.
DEV.
2.3
1,487
540
717
83
35
17
17
397.3
22.2
0.9
0.5
-
-
-
-
-
-
COEF. OF
VAR.
0.26
1.03
0.87
2.30
1.48
0.40
1.21
0.57
2.04
3.13
1.80
0.71
-
-
-
-
-
-
# OF
OBS.
18
18
18
17
16
18
15
16
14
16
10
3
13
13
13
13
13
13
* Composited samples
** Sensitivity of analysis
0.1 mg/1
34
-------
TABLE 2(G)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 085*
PARAMETER
pH
TDS, mg/1
YDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols , mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
10.3
1,590
1,200
60
50
1,092
510
249
14.5
1.2
3.4
1.0
1.6
< 0.1
1.1
0.4
0,5
1.5
LOW
3.6
580
140
1
1
4
1
7
0.1
0.4
0.1
1.0
< 0,1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
MEAN
7.9
902
471
20
11
400
160
96
2.6
0.8
0.9
1.0
< 0.9
< 0.1
< 0.3
< 0.2
< 0.3
< 0.3
STD.
DEV.
1.9
267
317
18
15
290
114
64
3,9
0.3
1.0
-
-
-
-
-
-
-
COEF. OF
VAR.
0.24
0.30
0.67
0.90
1.36
0.73
0.71
0.67
1.5
0.38
1.11
-
-
-
-
-
-
-
# OF
DBS.
9
13
13
13
12
27
22
23
11
12
8
1
13
13
13
13
13
13
* Composited samples
** Sensitivity of analysis
0.1 mg/1
35
-------
TABLE 2(H)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 095*
PARAMETER
pH
TDS, mg/1
YDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5,mg/l
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
NBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
10.2
26,800
19,980
17,270
17,270
43,300
25,000
15,595
4,400
305.0
320.0
710.0
0.7
30.9
10.8
10.7
3.5
0.5
LOW
1.3
8,560
4,730
116
40
2,500
2,409
2,391
9
4.0
0.5
104.0
0.4
2.4
< 0.1
0.3
< 0.1
< 0.1
MEAN
3.5
17,831
11,590
5,640
5,548
19,186
10,062
5,896
897
115.8
80,7
405.3
0.5
20.4
< 3.4
1.3
< 0.6
< 0.2
' STD.
DEV.
3.0
5,263
4,428
4,825
4,839
10,912
6,298
4,638
1,248
88.3
91.1
247.4
0.1
6.5
-
2.7
*•
-
COEF. OF
VAR.
0.86
0.30
0.38;
0.86
0.87
0.57
0.62
0.79
1.39
0.76
1.13
0.61
0.20
0.32
-
2.08
-
-
# OF
OBS,
16
13
13
13
13
22
22
14
15
15
9
3
13
13
13
13
13
13
* Composited samples
** Sensitivity of analysis
0.1 mg/1
36
-------
TABLE 2(1)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
INDUSTRIAL WASTEWATER 105 *
PARAMETER
PH
TDS, mg/1
VDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOG, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1**
Cu, mg/1**
Fe, mg/1**
Ni, mg/1**
Pb, mg/1**
Zn, mg/1**
HIGH
12.2
19 , 700
9,300
2,620
1,090
5,200
2,922
1,994
22.0
4.0
12.0
1,3
3.4
< 0.1
4.5
0.6
1.0
0.8
LOW
4.7
9,220
1,410
200
100
1,590
115
828
1.1
0.1
0.2
1.0
1.1
< 0.1
< 0.1
0.2
0.3
< 0.1
MEAN
10.8
13,201
4,266
1,026
410
3,363
1,795
1,335
7.3
1.0
2.7
1.2
2.2
< 0.1
< 1.1
0.4
0.6
< 0,2
STD.
DEV.
2.1
2,445
2,275
545
240
1,009
600
323
5.5
1.2
4.2
0,1
0.6
-
-
0.1
0.2
-
COEF. OF
VAR.
0.19
0.19
0.53
0.53
0.59
0.30
0.33
0.24
0.75
1.20
1.56
0.08
0.27
-
-
0.25
0.33
-
# OF
OBS.
11
14
14
14
14
26
24
22
11
12
6
3
12
12
12
12
12
12
* Composited samples
** Sensitivity of analysis =0.1 mg/1
37
-------
TABLE 2(J)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
BENCH SCALE PHASE
MUNICIPAL WASTEWATERS*
PARAMETER** PENNSVILLE
TDS
TSS
COD, mg/1
BOD5, mg/1
Nitrogen, mg/1
TKN, mg/1
Total P, mg/1
Of, mg/1
Cu, mg/1
Fe, mg/1
Ni, mg/1
Pb, mg/1
Zn, mg/1
480
40
300
119
0.6
16.6
13.5
< 1.0
< 0.25
< 1.0
< 2.5
< 2.0
< 1.0
UPPER PENNS
NECK
490
30
420
123
0.7
23.7
15
< 1.0
< 0.25
< 1.0
< 2.5
< 2.0
< 1.0
SALEM
480
25
300
97
0.5
12.9
10
< 1.0
< 0.25
< 1.0
< 2.5
< 2.0
< 1.0
PAULSBORO
460
70
547
185
1.0
20.4
12
< 1.0
< 0.25
< 1.0
< 2.5
< 2.0
< 1.0
WOODBURY
450
70
365
110
1.7
12.9
10
< 1.0
< 0.25
< 1.0
< 2.5
< 2.0
< 1.0
* Composited samples
** Represent mean values
38
-------
TABLE 3(A)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 015*
PARAMETER
pH
COD, mg/1
TOG, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH
11.9
90,200
6,300
77,000
0.3
2.8
0.5
0.9
0.6
20.0
0.4
<0.1
<0.1
0.0190
LOW
4.3 -'
189
763
380
<0.1
0.2
<0.1
0.2
<0.1
4.4
<0.1
<0.1
<0.1
0.0001
MEAN
8.59
«- 16,791
3,560
13,963
<0.14
1.1
<0.22
0.43
<0.17
7.86
<0.24
<0.1
<0.1
0.00478
STD.
DEV.
1.58
17,389
1,578
13,734
-
.8
-
0.23
-
4.87
-
-
-
0.00668
COEF. OF
VAR.
0.18
1.04
0.44
0.98
-
.73
-
0'.53
-
0.62
-
-
-
1.40
# OF
OBS.
58
44
15
43
9
9
9
9
9
9
5
5
5
7
* Grab type samples
** Sensitivity limit of analysis =0.1 mg/1
39
-------
TABLE 3(B)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 025*
PARAMETER
PH
COD, mg/1
TOC, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH LOW
11.7 1.9
12,800 81
429 25
3,500 42
0.3 <0.1
1.3 <0-1
<0.1 <0.1
1.3 <0.1
0.2 <0.1
8.2 <0.1
0.9 <0.1
<0.1 <0.1
0.6 0.3
0.0048 0.0001
MEAN
8.72
542
128.7
456.0
<0.11
<0.40
<0.10
<0.30
<0.11
<1.73
<0.14
<0.1
0.46
0.00129
STD.
DEV.
1.47
1,054
96.1
408.8
-
-
-
-
-
-
-
-
0.15
0.00122
COEF. OF
VAR.
0.17
1.94
0.75
0.90
-
-
-
-
-
-
-
-
.33
0.94
# OF
OBS.
193
150
34
163
47
47
47
47
47
47
5
5
5
44
* Grab type samples
** Sensitivity of analysis =0.1 mg/1
40
-------
TABLE 3(C)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 033*
PARAMETER
pH
COD, tng/1
TOC, mg/1
TOD ,mg/l
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH
12.1
9,280
822
12,500
0.3
16.6
0.2
20.0
0.3
20.0
0.6
<0.1
0.2
0.0060
LOW
2.3
56
17
30
<0.1
<0.1
<0.1
<0.1
<0.1
0.2
0.2
<0.1
0.2
0.0001
MEAN
7.73
754
200.2
630
<0.11
<0.60
<0.10
<0.80
<0.13
2.18
0.36
<0.1
0.20
0.00139
STD.
DEV.
2.07
1,212
189.1
1,140
-
-
-
-
-
3.24
0.02
-
0.00
0.00171
COEF. OF
VAR.
0.27
1.61
0.94
1.81
-
-
-
-
-
1.49
0.06
-
0.00
1.23
# OF
OBS
253
204
54
213
47
47
47
47
47
47
5
q
W
C
32
* Grab type samples
** Sensitivity of analysis - 0.1 mg/1
41
-------
TABLE 3(D)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 034*
PARAMETER
pH
COD, mg/1
TOC, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH LOW
11.0 1.9
38,100 48
218 12 .
4,625 30
0.9 <0.1
1.4 <0.1
0.2 <0.1
2.0 <0.1
0.2 <0.1
25.0 <0.1
1.0 0.2
<0.1 <0.1
0.2 <0.1
0.0143 0.0001
MEAN
6.51
687
50.3
273.3
<0.14
<0.37
<0.10
<0.38
<0.11
<2.15
0.5
<0.1
<0.16
0.00224
STD.
- i''DEV.
1.96
3,069
43.3
374.6
-
-
-
-
-
-
0.33
-
-
0.00319
COEF. OF
VAR.
0.30
4.47
0.86
1.37
-
-
-
-
-
-
0.66
-
-
1.42
# OF
OBS.
225
178
45
192
53
53
53
53
53
53
5
5
5
40
* Grab type samples
** Sensitivity of analysis =0.1 mg/1
42
-------
TABLE 3(E)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 045*
PARAMETER
PH
COD, mg/1
TOG, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**-
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH
5.1
884
416
850
1.0
2.4
0.5
8.6
0.4
20.0
2.5
<0.1
0.3
0.1635
LOW
0.7
16
416
63
<0.1
<0.1
<0.1
0.2
<0.1
3.2
0.7
<0.1
<0.1
0.0002
MEAN
2.48
515.1
416
407.6
<0.47
<0.56
<0.11
2.32
<0.21
6.70
1.16
<0.1
<0.22
0.00851
STD.
DEV.
0.37
120.0
-
170.1
-
-
-
2.18
-
3.39
0.81
-
-
0.02374
COEF. OF
VAR.
0.15
0.23
-
0.42
-
-
-
0.94
-
0.50
0.70
-
-
2.79
# OF
OBS.
132
111
1
107
35
35
35
35
35
35
5
5
5
47
* Composite samples based on flow
** Sensitivity of analysis =0.1 mg/1
43
-------
TABLE 3(F)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 055*
PARAMETER
pH
COD, mg/1
TOG, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH
10.4
5,700
480
2,050
0.2
0.4
<0.1
0.3
0.8
50.0
-
-
••
0.0058
LOW
6.5
760
320
300
<0.1
<0.1
<0.1
<0.1
<0.1
1.4
-
-
-
0.0001
MEAN
8.80
1,896
400
997.4
<0.11
<0.21
<0.10
<0.15
<0.18
12.9
-
-
-
0.00193
STD.
DEV.
1.14
1,276
110
368.1
-
-
-
«•
-
13.1
-
-
-
0.00187
COEF. OF
VAR.
0.13
0.67
0.28
0.37
-
-
••
-
-
1.02
-
-
-
0.97
# OF
OBS.
24
13
2
19
15
15
15
15
15
15
-
-
-
12
* Grab type samples
** Sensitivity of analysis
0.1 mg/1
44
-------
TABLE 3(G)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 065*
PARAMETER
pH
COD, mg/1
TOC, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH
9.2
5,780
3,364
1,310
0.4
0.5
<0.1
1.0
0.9
725.0
0.5
<0.1
0.4
0.0047
LOW
0.9
310
68
22
<0.1
<0.1
<0.1
<0.1
<0.1
0.4
0.2
<0.1
0.2
0.0008
MEAN
2.07
1,026
688.8
222.9
<0.20
<0.22
<0.10
<0.43
<0.16
47.6
0.32
<0.1
0.32
0.00247
STD.
DEV.
1.24
887
874.1
239.5
-
-
-
-
-
159.6
0.13
-
0.08
0.00128'
COEF. OF
VAR.
0.60
0.86
1.27
1.07
-
-
-
-
-
3.35
0.41
-
0.25
0.52
# OF
OBS.
102
71
16
41
20
20
20
20
20
20
5
5
5
17
* Grab type samples
** Sensitivity of analysis =0.1 mg/1
45
-------
TABLE 3(H)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 085*
PARAMETER
pH
COD, mg/1
TOC, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH LOW
10.2 2.2
1,582 23
2,080 1
4,360 10
0.4 <0.1
1.1 <0.1
0.2 <0.1
0.7 <0.1
0.8 <0.1
11.3 <0.1
I.I <0.1
<0.1 <0.1
0.4 <0.1
0.1080 0.0002
MEAN
7.40
321.2
172.5
202.6
<0.14
<0.57
<0.11
<0.28
<0.14
<2.54
<0.32
<0.1
<0.28
0.00748
STD. COEF. OF
DEV. VAR.
1.63 0.22
321.4 1.00
456.1 2.64
499.9 2.47
-
-
-
-
-
-
-
-
-
0.02439 3.26
# OF
OBS.
95
75
20
78
22
22
22
22
22
22
5
5
5
19
* Grab type samples
** Sensitivity of analysis =0.1 mg/1
46
-------
TABLE 3(1)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 095*
PARAMETER
PH
COD, mg/1
TOG, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
' HIGH
12.2
99,999
17,985
58,200
0.5
0.7
0.2
1.5
0.5
20.0
0.4
<0.1
0.8
0.0810
LOW
1.3
512
118
32
<0.1
<0.1
<0.1
<0.1
<0.1
0.2
<0.1
<0.1
0.2
0.0125
MEAN
5.18
23,100
7,875
9,600
<0.19
<0.21
<0.11
<0.39
<0.22
6.38
<0.25
<0.1
0.37
0.03542
STD.
DEV.
3.37
27,360
6,689
11,230
-
— «
••
w
-
7.29
-
-
0.28
0.02964
COEF. OF
VAR.
0.65
1.18
0.85
1.17
-
-
-
-
-
1.14
-
-
0.76
0.84
# OF
OBS.
51
39
10
40
8
8
8
8
8
8
4
4
4
6
* Grab type samples
** Sensitivity of analysis =0.1 mg/1
47
-------
TABLE 3(J)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
INDUSTRIAL WASTEWATER 105*
PARAMETER
pH
COD, mg/1
TOC, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH LOW
12.4 1.4
10,100 19
2,312 56
17,000 75
0.3 <0.1
8.6 <0.1
0.4 <0.1
16.2 <0.1
1.4 <0.1
75.0 <0.1
1.1 <0.1
<0.1 <0.1
3.7 <0.1
0.0200 0.0005
MEAN
9.75
2,904
815.4
2,668
<0.13
<2.04
<0.18
<1.38
<0.35
<19.07
<0.56
<0.1
<1.00
0.00334
STD. COEF. OF
DEV. VAR.
3.49 0.36
1,534 0.53
576.4 0.71
2,414 0.90
-
-
-
-
-
-
-
-
-
0.00483 1.45
# OF
OBS.
82
73
14
66
18
18
18
18
18
18
5
5
5
16
* Grab type samples
** Sensitivity of analysis =0.1 mg/1
48
-------
TABLE 3(K)
CHARACTERIZATION OF PARTICIPANT WASTEWATERS
PILOT PLANT PHASE
MUNICIPAL WASTEWATER 835*
PARAMETER
pH
COD, mg/1
TOC, mg/1
TOD, mg/1
Cu, mg/1**
Cr, mg/1**
Ni, mg/1**
Zn, mg/1**
Pb, mg/1**
Fe, mg/1**
Mn, mg/1**
Ag, mg/1**
Sr, mg/1**
Hg, mg/1
HIGH LOW
9.8 2.5
2,690 71
352 13
1,900 20
0.3 <0.1
0.5 <0.1
<0.1 <0.1
0.5 <0.1
0.4 <0.1
9.3 0.4
0.2 <0.1
<0.1 <0.1
0.3 <0.1
0.0092 0.0001
MEAN
7.39
393.7
91.9
280.6
<0.12
<0.16
<0.10
<0.17
<0.13
1.54
<0.14
<0.1
<0.22
0.00226
STD.
DEV.
0.70
292.5
73.9
221.2
-
-
-
M
-
1.52
-
-
0.00262*
COEF. OF
VAR.
0.09
0.74
0.80
0.79
-
-
-
-
-
0.99
-
-
1.16
# OF
OBS.
203
178
34
175
43
43
43
43
43
43
5
5
5
24
* Grab type samples obtained from Upper Perm's Neck Wastewater Treatment Plant
** Sensitivity of analysis =0.1 mg/1
49
-------
TABLE 4
CHARACTERIZATION OF COMBINED INDUSTRIAL & MUNICIPAL WASTEWATERS
BENCH SCALE PHASE
PARAMETER
pH
TDS, mg/1
VDS, mg/1
TSS, mg/1
VSS, mg/1
COD, mg/1
BOD_, mg/1
TOC, mg/1
TKN, mg/1
Total P, mg/1
Phenols, mg/1
MBAS, mg/1
Cr, mg/1
Cu, mg/1
Fe, mg/1
Vo'-
Ni, mg/1
Pb, mg/1 **
it **
Zn, mg/1
HIGH
3.1
3,250
1,230
90
80
908
340
230
39.6
4.6
9.2
14.5
2.3
0.9
7.2
0.7
1.0
2.8
LOW
1.9
1,900
390
1
1
570
170
155
3.0
2.3
3.1
14.5
0.3
0.5
3.2
<0.1
0.2
0.5
MEAN
2.6
2,466
861
18
14
688
293
196
18.1
3.4
6.6
14.5
0.8
0.7
4.9
< 0.2
0.5
1.2
STD.
DEV.
0.4
435
"4 . '
262
28
26
102
53
24
15.0
0.8
1.8
-
0.6
0.1
1.6
-
0.2
0.7
COEF. OF
VAR.
Q".l5
0.18
0.30
1.56
1.86
0.15
0.18
0.12
0.83
0.24
0.27
-
0.75
0.14
0.33
-
0.40
0.58
# OF
OBS.*
6
8
8
8
8
8
7
7
7
7
6
1
7
7
7
7
7
7
* Composited samples
** Sensitivity of analysis =0.1 mg/1
50
-------
treated in the prototype system, are tabulated in Table 5. The parameters cited
are for samples obtained at the neutralization tank influent or primary clarifier
effluent as noted in the Table. The statistical distribution of these key parameters
are illustrated in Figures 2, 3, and 4.
DISCUSSION
The characterization data presented in this chapter represent the summarized
results observed from the inception of the project in August, 1969, to the
termination of the pilot plant study in October, 1971. Based on the frequency
and number of observations accumulated during this time span, it was possible
to accurately define the magnitudes and patterns of the pertinent constituents
contained in the various wastewaters.
It is noted that there is some variation in the reported analyses from the
individual participants in the bench scale phase, Table 2, and the pilot plant
phase, Table 3. Although the sampling points were essentially the same, this
variation can be attributed to ?n-plant modes of operation and the influence of
the sampling date on process and cooling operations.
The coefficient of variation is indicative of the relative variations for each of
the water quality parameters cited. For example, the coefficient of variation
of the organic parameters (COD, BOD, TOC, and TOD) was generally higher
for the individual industrial waste samples recorded during the pilot plant
phase of the project than during the bench scale phase. This is reflected in
Tables 4 and 5 and can be attributed to the respective number of observations
and the nature of sampling. Conversely, a higher variation in suspended solids
data was noted during the bench scale phase, which is reasonable when
considering the nature of the test and the methods of obtaining the samples.
It is interesting to note that of the organic parameters listed in Tables 4 and 5,
the COD and TOC variations as measured by the coefficient of variation were
less than those for the BOD. This is most probably reflected by the accuracy of
the tests, the COD and TOC analytical procedures being less subject to inter-
ferences and human error than the BOD test. The variations in suspended solids
were higher than those reported for the organic parameters, although variations
in dissolved solids concentrations were about the same. The coefficients of
variation for phenols, nitrogen, phosphorus, and heavy metals followed no
specific pattern, although the magnitudes approximate those reported from
similar studies.
The distribution of organics, solids, and pH for the pilot plant influent water
are illustrated in Figures 1, 2, and 3. The organic data presented in Figure 2
most probably represents two populations. For example, the organic con-
centration of the wastewaters is considerably lower in the summer than in the
51
-------
TABLS 5
CHARACTERIZATION OF COMBINED INDUSTRIAL AND MUNICIPAL WASTEWATERS
PILOT PLANT PHASE
PARAMETER
pH
TDS, mg/1
VDS, mg/1
TSS, mg/1 .
VSS, mg/1
COD, mg/1
BOD5, mg/1
TOC, mg/1
TOD, mg/1
Phenols, mg/1
**
Color, Std. Units
Total P, mg/1
**
TK.N, mg/1
**
Ammonia Nitrogen, mg/1
**
N02 + NO mg/1
Cu, mg/1 """""""
Cr, mg/l'
Mi, mg/l"**
Zn, mg/1
Pb, mg/1***
. ***
Fe, mg/1
***
Mn, mg/1
***
Ag, mg/1
Sr, mg/1
Hg, mg/1
-'..>..<-
Al, mg/1
Cd, mg/1
S04, mg/1
MBAS, mg/1
Fecal Coliforms. Nn./lOO ml
NOTE: All analyses were made on
HIGH
5.0
3,182
1,182
100
SO
822
453
338
990
18.75
1,800
13.0
45.0
36.5
122.5
0.8
1.9
0.2
7.8
0.4
10-2
1.8
<0.1
0.6
0.0158
1.5
0.03
592
9.0
0
LOW
---I - -fcn»ii —
2.0
1,275
290
28
20
420
136
109
237
0.75
200
0.2
10.5
4.0
0.7
" 0.1
<0.1
-------
0>
Oi
CO
z
UJ
o
900 p-
800 -
700 -
600
500
400
300
200
VARIATION IN THE
PILOT PLANT COMPOSITE
WASTEWATER ORGANIC PARAMETERS
I00_
TOC
I
_L
I
0.1
I 10 30 50 70 90
PERCENT OF VALUES LESS THAN GRAPH VALUE
99
99.9
-------
2800
2400
a 2000
x.
o>
600
CO
Q
co" 1200
o
800
400
0.1
1
VARIATION IN THE
PILOT PLANT COMPOSITE
WASTEWATER SOLIDS
_L
I 10 30 50 70 90
PERCENT OF VALUES LESS THAN GRAPH VALUE
99
140
120
100 —
80
0
99.9
o»
E
co
CO
60 co"
CO
40
20
-------
VARIATION IN THE
PILOT PLANT COMPOSITE
WASTEWATER pH
4.4
4.0
3.6
pH 3.2
2.8
2.4
2.0
0.1
I
I
I
I
10 30 50 70 90
PERCENT OF VALUES LESS THAN GRAPH VALUE
99
99.9
Tl
MB*
CO
s
-------
winter due to the volume of cooling water diluent present during the warm weather
months. This is reflected in the probability curve geometry and should be con-
sidered when designing a waste treatment facility which is capable of producing an
acceptable effluent during each season. In a practical sense, less importance is
attached to the suspended solids distributions shown in Figure 3. This is predicated
on the fact that the suspended solids observed in the pilot plant effluent following
trucking and temporary storage are liable to be quite different from those in a
wastewater discharge from the equalization facility at an individual plant and
conveyed to the regional facility through an interceptor. As a matter of judgment,
the levels shown in Figure 3 are considered to be conservative. The dissolved
solids levels are more representative, however, and should be indicative of that
expected for the combined wastewater influent to the regional treatment facility.
As noted, there was much less variation in pH values, attributable in part to the
dampening of batch dumps and surges by the equalization facilities preceding the
pilot plant system.
In summary, certain patterns, both seasonal and operational, can be detected in
the tabular and graphical presentation of the wastewater characterization data.
Although one must recognize the constraints which are prevalent when interpreting
this data (sampling methods and frequencies, analytical procedures, interferences,
etc.), it still provides a rational approach for establishing an individual and
collective characterization picture of the wastewaters involved. It is from this
information that plant design, cost evaluation, and cost allocation were based.
56
-------
SECTION V
BENCH SCALE TREATABILITY STUDIES
There are many aspects involved in the development of design criteria for waste-
water treatment facilities through the use of bench scale and pilot scale treata-
bility studies. The first logical step toward evaluating the treatability of a
wastewater is the application of bench scale simulation techniques, observing
system responses under various environmental and physical conditions.
There are several approaches which can be employed to evaluate the individual
processes which comprise a total waste treatment system. It should be recognized,
however, that regardless of the approach taken, the ultimate accuracy of the
information developed from bench scale studies depends on several conditions,
namely:
1. The characteristics of the wastewater used in the treatability tests are representa-
tive of those anticipated in the field;
2. The physical nature of the bench or pilot scale process is similar to the prototype
unit;
3. Independent and dependent operational variables are considered; and,
4. Environmental parameters affecting process efficiency are defined. Observing
these and other guidelines, bench and pilot scald simulation techniques can pro-
vide limited process information with respect to applicability, establishment of
predictor relationships, and approximate determinations of process capacity.
Although information garnered during these studies must be applied in a judicious
manner, a treatability study which is properly programmed and carefully implemented
does afford the basis for the logical development of unit process selection, design,
and predictive performance.
OPERATIONAL PROCEDURES
The scope of the bench scale treatability program included an evaluation of pre-
and primary treatment processes, secondary biological treatment, and ancillary
studies related to sludge dewatering, chemical treatment, and physical treatment.
The bench scale equipment consisted of standard laboratory glassware, commercially
available testing equjpnent, and specially constructed process models. This
equipment is described in the following sections of this Chapter.
57
-------
The laboratory analytical schedule was programmed to provide sufficient data for
adequately evaluating each of the processes considered. Analyses were performed
using accepted analytical techniques, primarily conforming to Standard Methods,
12 Ed. (Reference 1). Many of the methods used in the treatability studies were
based on those outlined in Water Pollution Control (Reference 2).
PRE- AND PRIMARY TREATMENT EVALUATION
Equalization
Experience has shown that treatment processes, whether physical, chemical, or
biological, perform at a higher rate of efficiency if the hydraulic and organic
load fluctuations to the process can be dampened. The most prevalent situations
where the equalization principle should be applied are summarized as follows
(Reference 3):
1. Biological Treatment
A. Poisoning by high concentrations of toxic materials, even if only of
slight duration.
B. Inhibition by high concentrations of normally biodegradable materials.
C. Short-term upsets caused by extreme deviations of input; transient effects.
2. Chemical Treatment -Variations in chemical demand, if not smoothed out,
will require variable rate feeders, and sophisticated control systems.
•
3. Physical (equalization without treatment) -Where effluent regulations limit
the concentration of a component in the discharge to a value which is above
its long-term mean value, equalization facilities can smooth the concentration-
time curve and attain compliance.
Equalization will occur in varying degrees at the plant site of each participant.
Additionally, there will be some equalization in the conveyance system, and finally,
equalization at the Regional plant can be instituted if considered necessary for
adequate process performance. Although no bench scale equalization studies were
conducted per se, a review of the individual modes of equalization and their
influence with respect to regional treatment are discussed individually.
Equalization Basins at the Individual Plant Sites
Basin Size;
In essence, each industry will size its equalization basin based on the cost of
58
-------
buying more capacity in the interceptor sewer and treatment plant versus the cost
of installing a larger equalization basin. Minimum interceptor costs would result
by never exceeding the average annual flow rate by over 10 percent. However,
if a particular industry experienced significant seasonal variations in wastewater
flows, a very large equalization basin would be required and it might be more
economical to buy more capacity in the regional system.
Minimum Basin Size;
The smallest equalization basin that an industry could economically consider would
be designed only to store contaminated storm water runoff until it could be pumped
into the system with the 10 percent allowable excess flow rate.
Using flow data presented in the Preliminary Engineering Report which was submitted
in June, 1970, the size and detention time of the minimum equalization basin
required for each industry pumping into the interceptor sewer is presented in
Table 6. The minimum basin size is based on holding all of the runoff from a storm
having five inches of precipitation in 24 hours.
With the exception of Hercules, which already has a relatively large equalization
basin, the detention time provided by the minimum basin is rather small. A further
consideration is that the operating volume in a small basin would normally be kept
low so as to provide the maximum possible retention of storm water after a storm
began. Therefore, the detention of process wastewaters provided by the minimum
size equalization basins would normally be very small, and a negligible effect on
equalizing fluctuations in the quality characteristics of the wastewaters would be
expected.
Maximum Basin Size;
The maximum basin size would result from dampening out fluctuations in process
wastewaters. Particularly critical would be seasonal fluctuations such as occur
with industries having a large flow of contaminated, once-through cooling water.
During the summer months, when the river temperature is high, more cooling
water is required to achieve the same cooling effect that is obtained in the winter
with considerably less water.
Depending on the amount of cooling water involved, it is indicated that an
equalization basin having a detention time of between five and 10 days at the
average yearly flow is required if seasonal flows are balanced using an excess
pumping factor of 10 percent.
Currently, it is doubtful if five to 10 days equalization capacity will be economical
and a practical maximum would probably be one to two days.
59
-------
TABLE 6
EQUALIZATION BASIN SIZE BASED ON STORM WATER RUNOFF^
Location
Monsanto
Repauno
Mobil
Houdry
Shell
Texaco
BFG
1990
Flow
MGD
9.0
7.2
26.0
0.4
6.0
7.9
2.4
Excess
Time to
Allowable Pump
Volume/^ Pumping All of
of Runoff Rate Runoff
MG
0.68
1.36
20.50
0.14
0.68
5.04
0.68
MGD
0.9
0.72
2.6
0.04
0.6
0.79
0.24
Days
0.75
1.90
7.90
3.50
1.10
6.40
2.83
Detention of Process
Wastewater Provided
by Basin Equal to
Runoff Volume
Days
0.07
0.19
0.80
0.35
0.11
0.64
0.28
(a) Based on flows and runoff volumes from Table V-l, Task C-l
(Preliminary Interceptor Report)
(b) Based on five inches of rain in 24 hours
60
-------
Effect of Equalization Basin on Wastewater Characteristics;
Assuming each industry will provide some equalization capacity to dampen out
fluctuations in wastewater flows, there will be some effective equalization of the
quality characteristics. The degree of equalization will depend on the capacity
and the flow characteristics of the basin.
Two types of flow can occur in a basin: (1) plug flow, and (2) completely mixed
flow. The relative amounts of these two types of flow plus the degree of short-
circuiting and dead space that occurs in a basin determines the flow characteristics.
Ideally, a completely mixed basin without any dead space or short-circuiting would
provide the highest degree of equalization of the fluctuations in the quality
characteristics of a wastewater. In such a basin, the concentration of any con-
stituent in the effluent from the basin would be the same as the concentrations
within the basin. There would, therefore, be a maximum dampening of the fluctu-
ations in influent quality characteristics.
Conversely, a basin with plug flow-regard I ess of the amount of dead space and
short-circuiting-would provide little or no equalization of quality characteristics.
Effluent concentrations would reflect those in the influent after the necessary time
lag.
Although short-circuiting and dead space can be minimized by proper baffling and
inlet and outlet structures, completely mixed systems are obtained only by providing
external agitation. The cost of building and operating such a basin is therefore
higher than for one with plug flow characteristics.
Because the equalization basin requirements at the individual plants are based
solely on dampening out variations in flow rate, there is no economic incentive
for installing a basin with completely mixed characteristics. The design of the
basins vill essentially be predicated on minimizing costs and will therefore have
flow characteristics that are a combination of plug, mixed, short-circuiting, and
dead space. The amount of mixing that does take place will be the result of wind
action, thermal currents, inlet turbulence, etc., and essentially will be uncontrolled,
Previous experiments have indicated that such basins usually have about 10 to 40
percent completely mixed characteristics.
Assuming the actual basins are approximately 25 percent completely mixed, with
the remaining characteristics being divided equally among short-circuiting, plug
flow, and dead space, the basins could effectively equalize fluctuations in
concentrations that occur over a time interval equal to 25 percent of the theoretical
detention time of the basin. Therefore, unless a participant constructs an unusually
large equalization basin, only short term fluctuations in quality parameters will
be equalized. Assuming the typical equalization capacity
61
-------
provided to dampen out wastewater flows is equal to two days, 25 percent of
this, or approximately 12 hours, would be available to dampen out fluctuations
in concentrations.
Equalization in Interceptor
The flow characteristics of the interceptor will be almost TOO percent plug flow.
.Some mixing will occur at the pumping stations, but this would be essentially
negligible.
Because the flow in the interceptor will have plug characteristics, there will be
no dampening out of the fluctuations in concentrations of the various constituents
in the combined wastewaters. This can only occur in the individual equalization
basins.
As each individual wastewater is pumped into the interceptor, the effect is
primarily one of blending together wastewaters having different concentrations of
the various quality characteristics. Of the reactions that will be taking place
among the various wastewater constituents, the most significant at the present time
appears to be the combination of alkalinity and acidity. There will be a dampening
of neutralization requirements as the alkaline wastewaters tend to neutralize the
predominantly acidic wastewaters. Moreover, there are preliminary indications
that the overall BOD load might be reduced slightly due to the interaction of all
the wastewaters. The laboratory work to date indicates that the BOD of the
integrated wastewaters is approximately 10 percent less than that calculated from
the individual wastewaters. This, however, is based on a completely mixed
system and the reduction in the interceptor would be considerably less.
The preliminary design and operating characteristics of the interceptor sewer permit
the following conclusions to be drawn concerning equalization capacity in the
interceptor:
1. The capacity provided in the individual equalization basins required for storm
water runoff would have only a minor effect on equalizing quality characteristics.
2. The equalization capacity provided to level out fluctuations in the flow of
process wastewater would have some effect on equalizing quality characteristics.
Assuming typical basin design and an effective detention time of two days,
variations in quality characteristics occurring over a 12-hour period would
probably be effectively equalized.
3. There will be little or almost no opportunity for leveling out fluctuations in
quality characteristics in the interceptor sewer because of its plug flow characteri-
stics. There will be an opportunity for reactions to take place among the
62
-------
constituents of the various wastewaters, but with the exception of neutralization
this effect appears to be minor.
Equalization at the Regional Plant Site
I n order to assay the need for providing additional equalization facilities at the
regional treatment plant site, one must first consider those wastewater flow and
quality characteristics which merit consideration in terms of regional plant
equalization.
Flow;
Because the interceptor is being designed for partial length as a pressure system,
it is not economically attractive to size facilities to handle peak flows. As
previously discussed, tentative restrictions on fluctuations in the flow rate from
each industrial source have been set at plus 10 percent of the design flow. Those
industries pumping directly to the treatment plant would also be required not to
exceed 10 percent of the design flow. These restrictions would reduce the need
for surge basin requirements at the regional plant site.
Solids;
1. Suspended Solids - equalization is not required to dampen out fluctuation in the
suspended solids load. Settleable solids will be removed in the primary clarifiers,
and there is no real advantage in operating at a uniform concentration. Solids
that can damage either the interceptor or treatment plant would not, however, be
permitted in the system.
2. Dissolved Solids - biological processes are upset by large and rapid changes in
the concentration of dissolved solids. The fluctuations must be substantial, however,
and would have to exceed an increase of approximately 10,000 mg/l in less than
24 hours.
Biochemical Oxygen Demand;
Changes in the concentration of BOD do not usually upset activated sludge units
unless the variation is large or a degree of toxicity is present. If the change
results in a higher loading in terms of Ibs BOD/lb MLVSS/day, the percent of BOD
removal would decrease because activated sludge efficiency is responsive to
loading.
The secondary clarification process following activated sludge can be upset if
fluctuations in the BOD load result in sludge bulking. Although the cause of
bulking is not fully understood, activated sludges have been difficult to contain
63
-------
"
under some loading conditions and particularly when the character of the BOD load
is changing.
The data presented in Section IV indicate that the regional plant would normally
have to be operated at fairly conservative activated sludge loadings to insure that
effluent standards were met during periods of high BOD loads which "short-circuit
through the participant equalization basin and the regional interceptor.
Most of the variable BOD load can be attributed to a small volume of industrial
waste flows such as DuPont Repauno. It would be much more economical to provide
equalization basins for these flows rather than for the entire waste stream.
It should also be noted that the analytical data for the one industrial plant accounting
for the high BOD load is based on several in-plant samples that are blended to give a
representative sample. This method could result in more extreme variations in BOD
concentrations than would occur if one representative stream were available for
sampling. In any case, the need for equalizing the BOD load will depend on the
situation at only a few of the participant industrial plants.
Neutralization;
Equalization of alkalinity and acidity is advantageous if there is a net savings
in neutralization costs. Such a situation would occur if a waste stream varied from
acidic to basic on an hourly or daily basis, but would tend to "self-neutralize"
if there were sufficient detention time. There is no advantage, however, in
equalizing a waste stream that is consistently acidic or basic because the net amount
of chemicals required for neutralization remains essentially the same.
If one regional plant is constructed, the composite waste stream, according to the
characterization data cited in Section IV, would always be acidic so there would
be no advantage in equalization.
Potentially Toxic Constituents;
Materials that are capable of damaging the processes incorporated at the treatment
plant, particularly the biological processes, will not be permitted in the regional
system unless adequately diluted. Therefore, slug discharges of pesticides, solvents/
large quantities of phenolic compounds, etc., will have to be regulated at the source
by pre-treatment requirements.
Disinfection;
Bacterial analytical information has indicated that the industrial wastewaters are
adequately disinfected by the low pH of the integrated waste stream. It is
64
-------
reasonable to assume that the municipal wastewaters would also experience
some degree of disinfection if mixed with the industrial waters for a sufficient
period of time. Therefore, there could be an advantage in equalization if it
resulted in significant reduction in disinfection requirements.
X
Summary of Equalization
The need for equalization of the entire regional wastewater flow does not appear
to be economically attractive or technically justified. This is underscored by the
study conducted expressly for evaluating the effects of transient loadings using the
Chambers Works flow. The results of this study are considered in Section VI of this
report.
Neutralization
As part of the wastewater characterization program, the alkalinity, acidity, and
amount of acid or base required to neutralize a sample to pH 7.0 were determined.
In this task, these results were combined with flow data, and analyzed with respect
to each individual industry's location along with the proposed interceptor route to
ascertain cumulative neutralization requirements.
Municipal wastewaters were not included in the neutralization calculations.
Although domestic wastewaters typically have about 5.0 meq/l (250 mg/l CaCC>3)
alkalinity, their pH values were usually in the range of 6.5 to 7.5 and therefore
do not require neutralization.
Procedure
The amount of acid or base required to neutralize a sample to pH 7.0 was determined
in accordance with Standard Methods (Reference 1). The results included herein are
based on approximately 10 to 15 samples for each individual wastewater. Four
analyses had been performed on the integrated wastewater and were available to
check the cumulative requirements of the individual wastewaters.
The wastewater streams of two industries could not be sampled adequately before
existing neutralization facilities. The neutralization requirements for these two
wastewaters were therefore determined from plant operating records.
Results
1. The neutralization requirements for the individual wastewaters are presented in
Table 7. The results are summarized in terms of high, low, and average require-
ments .
65
-------
TABLE 7
NEUTRALIZATION REQUIREMENTS OF INDUSTRIAL WASTEWATERS
Wastewater Condition pH Required to Neutralize to pH 7.0
on
021
031
041
061
071
081
091
High
Low
Average
High
Low
Average
High
Low
Average
High
Low
Average
High .
Low
Average
High
Low
Average
High
Low
Average
High
Low
Average
V
N.A.
N.A.
N.A.
9.1
2.7
7.0+
8.2
3.7
7.0+
3.5
2.0
2.6
2.5
1.2
1.8
11.4
2.7
7.0+
N.A.
N.A.
N.A.
10.2
1.3
2.0
Acid (a)
meq/l Equiv/day meq/l
28
5
16
2.18 44,000
31.60
0.44 40,000
1.40
18.50
2.46
8.88
121.50
5.70
74.0
5.56 6,100
93.20
0.56 6,300
162.0 700,000
104.0
100.0
Base (a)
Equiv/day
15,000
2,600
8,500
663,000
mm
126,000
2,700,000
360,000
1,300,000
1,370,000
64,000
840,000
103,000
450,000
430,000
High 11.0 5.0 5,000
101 Low 4.0 5.0 5,000
Average 7.0+ - -
(a) Equivalents/day based on 1975 flow, (preliminary estimate)
1 meq/l = 50 mg/l CaCOs - 37 mg/l Ca(OH)2 = 40 mg/l NaOH
66
-------
2. The cumulative neutralization requirements as the individual wastewaters were
combined along the proposed interceptor route are summarized in Table 8. The
cumulative requirements are presented for three different conditions: (1) typical
effluent conditions at the individual plants, (2) the most basic conditions, and
(3) the most acidic conditions.
3. The results for the typical conditions indicate that 8.7 meq/l of base would be
required to neutralize the industrial waste stream at the regional treatment plant.
For example, this amounts to 2,570,000 equivalents/day, or 176,000 Ibs/day of
90 percent CaO at a flow of 78.6 MOD.
4- The most acidic conditions require approximately twice as much base for
neutralization as do the typical conditions.
5. The most basic conditions indicate that a small amount of acid might be required
to neutralize the industrial waste stream at the regional plant. The theoretical
amount required, however, is quite small, and in view of the fact that unusual
operating conditions would have to occur simultaneously at several plants, it is
doubtful if this condition would ever occur.
6. Neutralization results for the integrated wastewater indicated that an average
of 9.22 meq/l bf base was required for neutralization. This compares favorably
with the 8.7 meq/l figure previously cited.
Summary of Neutralization
The results of the neutralization studies indicate that the industrial wastewater
stream at the Regional Treatment Plant would normally require approximately
8.7 meq/l of base for neutralization. The most acidic conditions experienced
in the analytical program required approximately twice as much neutralization
as the normal conditions. Because unusual operating conditions would have to
occur simultaneously at several plants, it is doubtful if the pH of the waste-
water stream would ever be above 7.0.
Chemical Coagulation and Flocculation
Studies were conducted on seven of the nine individual wastewaters to determine
the potential for coagulation and flocculation as pretreatment. The two waste-
waters that were excluded from the studies had been shown previously to have very
little potential for pretreatment for suspended solids removal.
An integrated sample consisting of proportional volumes of the individual waste-
waters was also analyzed to obtain a preliminary evaluation of its coagulation and
flocculation potential before a more detailed evaluation was conducted during the
operation of the pilot plant.
67
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TABLE 8
CUMULATIVE NEUTRALIZATION REQUIREMENTS IN INTERCEPTOR
oo
Interceptor
Station
Flow
MGD
National Park
Mantua
Greenwich
Oldmans
5
8
34
37
.4
.7
.0
.0
Typical Conditions
Base Required
me a/I
Equiv/day
Most Basic Conditions
Acid Required
meq/l
2.2
(0.20)
3.4
3.1
(6,300)
432,200
432,200
1
6
6
.7
.2
.0
Equiv/day
44,
56,
793,
843,
000
400
800
800
Most Acidic Conditions
Base Required
meq/l
32.5
23.1
7.8
7.5
Equiv/day
663,
759,
1,004,
1,054,
000
700
700
700
Deepwater
Treatment Plant
78.6
8.7 2,572,200 1.4
419,800
17.2
5,124,700
-------
Procedure
The methodology wus as follows:
1. Analyze raw waste sample for COD, suspended solids, pH and unusual
characteristics.
2. Place one liter portions of raw waste in jars on a six-jar stirrer and check
stirrer operation.
3. During a rapid mix of 100 rpm add the coagulant and mix for one minute.
Use alum at doses of 2, 4, 8, 16, 32 and 64 mg/l.
4. Flocculate for 30 minutes at 30 rpm.
5. Settle for 30 minutes.
6. Visually observe the results. Measure the COD, suspended solids, and pH
of the supernatant in the jar or jars which have the best visual results.
7. Repeat steps 1 and 2 for fresh samples of the raw waste.
8. Adjust pH of the one liter portions to 4, 5, 6, 7, 8 and 9 with sodium
hydroxide or sulfuric acid.
9. To each jar add the optimum alum dose previously determined in steps 1
through 6.
10. Repeat step 6.
Results
The results for coagulation and flocculation without pH adjustment are summarized
in Table 9. Table 10 summarizes results with pH adjustment. Wastewaters 061
and 091 had removals of over fifty percent in the chemical oxygen demand (COD),
and subsequent tests were performed on these two wastewaters. These results are
summarized in Table 11.
Wastewater Oil:
When the wastewater was treated with a dose of 64 mg/l of alum, good flocculation
occurred. At lower doses the particles were more discrete in nature, and little
mechanical entrapment occurred. Good settling characteristics were found present
with the 64 mg/l dose.
69
-------
TABLE 9
SUMMARY OF RESULTS FOR FLOCCULATION WITHOUT pH ADJUSTMENT
Wastewater
Sample
Number
Oil
041
061
071
081
091
101
191
Optimum
Alum Dose
mg/1
64
8
32
8
8
8
8
8
Suspended
Initial
pH
9.15
2.02
1.78
1.79
8.52
1.38
11.2
3.0
Initial
mg/l
100
20
100
320
60
6,500
1,420
0
Final
mg/1
0
20
40
20
0
90
88
0
Solids
Percent
Removal
100
0
60
93.8
100
98.9
93.9
__
Chemical Oxygen Demand
Initial
mg/l
12,520
373
1,059
74
326
17,600
4,510
573
Final
mg/l .
11,640
365
863
58
283
8,400
3,690
5.55
Percent
Removal
6.4
2.1
18.5
21. £
15.2
52.3
18.2
1.4
Comments
Large floes formed .
No visual effect of alum.
Large number of floe particles .
Small floes with good settling
characteristics.
Some floating solids; clear
supernatant .
Excellent settling; clear
supernatant .
Slow settling but good solids
removal .
No visible flocculation
occurring.
-------
TABLE 10
SUMMARY OF RESULTS FOR FLOCCULATION WITH pH ADJUSTMENT
Wastewater
Sample
Number
Oil
041
061
071
081
091
101
191
Optimum
Alum Dose
mg/l
64
8
32
8
8
8
8
8
Suspended Solids(a)
Optimum
pH
9.15
9.10
7.01
7.15
7.01
7.00
6.89
9.30
Initial
mg/l
100
(b)
20
660
100
120
6,500
1,300
(c)
0
Final
mg/l
0
(b)
20
60
20
0
60
60
(c)
0
Percent
Removal
100.0
(b)
0
91.0
80.0
100.0
99
95.4
(c)
Chemical Oxygen Demand
Initial
mg/l
12,520
419
1,120
101
385
17,600
3,160
577
Final
mg/l
11,640
376
556
74
327
18,400
2,360
500
Percent
Removal
7.0
10.3
50.3
26.8
15.1
-
25.3
13.3
Comments
Good flocculation; clear
supernatant .
Good flocculation at high pH .
Excellent flocculation. Parti-
cles come out of solution as
pH is raised .
At lower pHs, poor settling;
at high pHs excellent
flocculation .
Clear supernatant; some
floating solids.
Particles go into solution as
pH is raised .
Particles in supernatant; slow
settling.
Good flocculation at high pH .
(a) Initial suspended solids refers to suspended solids concentration before pH adjustment.
(b) As pH is raised flocculant particles come out of solution.
(c) At pHs above 4.0, solids begin to come out of solution.
-------
TABLE 11
RESULTS OF ADDITIONAL COAGULATION AND FLOCCULATION STUDIES
WASTEWATER SAMPLE
061* 091**
Optimum Alum Dose mg/l 32 8
Optimum pH 3.09 1.46
COD
Initial, mg/l 460 18,500
Final, mg/l 304 13,200
Percent Removal 33.9 . 28.6
BOD5
Initial, mg/l 260 9,575
Final, mg/l 226 7,950
Percent removal 13.1 17.0
*Good flocculent suspension
** Excellent settling
72
-------
The effect of varying the initial pH of the wastewater sample was found to yield
no additional removal of COD.
Although the optimum doses resulted in essentially the complete removal of the
suspended solids, the reduction in COD was only 7.0 percent.
Wastewater 041:
Few solids were present in the raw wastewater and therefore little success was
achieved by coagulation and flocculation.
As the pH of the wastewater was raised, however, a large volume of dissolved
solids went into suspension. At high pH values, good flocculation was found to
occur. Maximum removal in COD was found to be 10.3 percent.
Wastewater 061:
At the low pH of the raw wastewater sample, moderate success was achieved by
the flocculation process. As the pH of the wastewater was raised, however,
material came out of solution and excellent flocculating conditions developed.
At an alum dose of 32 mg/l and a pH of 7.01, 90.0 and 50.3 percent removals
were obtained for suspended solids and COD respectively.
Additional studies, including five-day BOD analyses, were performed on
wastewater 061 and are summarized in Table 11. An alum dose of 32 mg/l
at a pH of 8.09 produced a COD removal of 33.9 percent and a BOD removal
of 13.1 percent. Although the subsequent test produced a smaller COD
removal, the most significant fact is that the BOD removal is considerably less
than that for COD. This would indicate that a large percentage of the
suspended material can be chemically oxidized, but not biologically oxidized.
Wastewater 071:
Good flocculation and suspended solids removal were obtained for the waste-
water both with and without pH adjustment, COD removals were not as good,
however, with the maximum removal being 26.8 percent at a pH of 7.15 and an
alum dose of 8 mg/l.
Wastewater 081:
The majority of solids contained in the sample were floating solids, and
flocculation had no effect on them.
The fine suspended solids found present in the sample were found to flocculate
well regardless of initial pH. COD and suspended solids removal were not found
to be a function of initial pH. Maximum COD removal was 15.2 percent.
73
-------
Wastewater 091:
Characteristically, this wastewater has a low pH and high suspended solids content.
At a very low coagulant dose, high CODand suspended solids removals were achieved.
While some bridging and flocculation occurred, the majority of the particles remained
discrete. At an alum dose of 8 mg/l and a pH of 1.38, 98.9 and 52.3 percent
removals were obtained for the suspended solids and COD respectively. While some
removal can be attributed to coagulation and flocculation, most of the removal
appeared to be the result of sedimentation.
No success was achieved by varying the initial pH of this wastewater because at
higher pH values, the solids go into solution.
Subsequent studies resulted in a 28.6 percent removal of COD and a 17.0 percent
removal of five-day BOD at an alum dose of 8 mg/l and an initial pH of 1.46.
Although the COD removal was substantially less in this test, the BOD results
indicate that the BOD load of this waste can be reduced significantly with a small
amount of flocculation and settling.
Wastewater 101:
The raw wastewater sample contained a large number of particles for flocculation.
At its raw pH, moderate removals were achieved.
The effect of varying the pH while keeping the dose constant was found to increase
the removals slightly, but particles remained suspended in the supernatant. The
optimum dose was 8 mg/l alum at pH of 6.89. The maximum reductions in suspended
solids and COD was 95.4 and 25.3 percent respectively.
Wastewater 191 (Integrated Wastewater):
At its raw pH of 3.0, very few particles were present in the integrated wastewater
sample and therefore flocculation resulted in negligible removals.
Characteristically, as the pH of the integrated sample is raised, dissolved material
goes into suspension. Although the opportunity for flocculation improves at a higher
phi values, the optimum dose and pH in this study resulted in a maximum COD removal
of only 13.3 percent.
Summary
1. The results of this task did not indicate a significant potential for coagulation and
flocculation as pretreatment for wastewaters Oil, 041, 071, 081, and 101.
74
-------
2. The results for wastewater 061 indicate that significant COD removals and
smaller BOD removals can be achieved at a neutral pH with an alum dose of
32 mg/l. The high alum dose required, and the lesser effect on BOD tend to
reduce the attractive ness of coagulation and flocculation on this wastewater.
3. The results for wastewater 091 indicate that significant COD, suspended
solids, and BOD removals could be achieved with low alum doses at the acidic
pH of the raw waste.
4. From the preliminary results for the integrated wastewater sample, it appears
that there is not a significant potential for flocculation coagulation at the
regional plant.
Effect of pH Adjustment without Chemical Addition
During the performance of the P-l tasks, it became apparent that the integrated
industrial wastewater had a considerable amount of dissolved material that tended
to come out of solution as the pH was raised. In this study, the effect of pH
adjustment as a sole method of treatment was further investigated, with particular
attention given to the amount of base required for pH adjustment and the correspond-
ing effect upon settleable solids and heavy metals.
Procedure
1. A titration curve of the integrated industrial wastewater was prepared using
sodium hydroxide. The results were then plotted as pH versus meq/l of base
added.
2. Four one liter samples of the integrated wastewater were placed in Imhoff
Cones and the pH adjusted to approximately 7.0, 9.6 and 11.9 respectively.
The pH of the fourth sample was not adjusted.
3. After one hour, the heavy metal concentration in the supernatant of each
sample was measured.
4. After 18 hours, the volume of solids in all samples was measured.
Results
1. The titration curve for the integrated wastewater is presented in Figure 5.
2. Table 12 summarizes the effect of pH adjustment on the solids present in the
integrated wastewater.
75
-------
Figure 5
16
14
12
10
9
0>
E
TITRATION CURVE FOR
INTEGRATED WASTEWATER
J I I
I I
345678 9 10 II 12
pH
76
-------
TABLE 12
SUMMARY OF EFFECT OF PH ADJUSTMENT ON SOLIDS
IN THE INTEGRATED WASTEWATER
Sample
1
2
3
pH
7.0
9.6
11.9
Volume of
Solids (a)
ml
8.0
16.0
30.0
Observations
Fine particles, poor settling.
Fine particles, slow settling.
Particles very large, excellent
settling, some color removal.
Unadjusted 3.2 0.01 Very few particles visible.
(a) After 18 hours settling in an Imhoff Cone.
-------
3. Table 13 summarizes the effect of pH adjustment on heavy metals.
Summary
A large amount of settleable material can be removed from the integrated waste-
water by raising the pH, with the effects becoming particularly significant above
a pH of 7.1. At a pH of 11.9, large particles which settled rapidly were obtained.
Seventeen meq/l (850 mg/l of CaCC^) were required to adjust the pH to 11.9.
Similar effects were observed for heavy metal concentrations. With the exception •
of zinc and strontium, the heavy metals investigated were reduced below the 0.1
mg/l sensitivity of the spectrophotometer by'adjusting the pH to 11.9.
Sedimentation Analyses of Untreated Wastewaters
Sedimentation analyses were conducted on the individual industrial wastewaters to
determine the possible need for primary sedimentation at the individual plant sites.
An integrated sample consisting of proportional volumes (based on 1975 flows) of
the individual wastewaters was also analyzed in order to establish a preliminary
evaluation for primary clarification efficiency at the future regional treatment plant.
r
Preliminary sedimentation analyses indicated that extensive analyses are not required
at this time based on the low suspended solids concentrations of the individual
wastewaters. The procedure as described herein'was therefore used to delineate those
streams potentially requiring gravity separation from those where it was not deemed
necessary.
Procedure
—^—— . t
;
The methodology was as follows: !
1. Each sample was neutralized to a pH of 7.0 and thoroughly mixed. A volume of
one hundred ml was then withdrawn for an initial suspended solids analysis.
2. One liter of the neutralized sample was then placed in a 1000 ml graduated
cylinder equipped with sampling ports.
3. After a settling time of 10 minutes, 100 ml was removed from the sample port
located 11.2 inches below the initial water surface in the cylinder. This sample
was then analyzed for a final suspended solid concentration.
The settling that occurs under these conditions is indicative of that which would
occur in ajclarifier with an overflow rate of approximately 1000 gpd/ft .
78
-------
TABLE 13
SUMMARY OF THE EFFECT OF PH UPON HEAVY METALS
IN THE INTEGRATED WASTEWATER
pH
11.90
9.60
7.11
3.20
Cr,
mg/l
<0.1
0.2
0,2
0.6
Cu,
mg/l
<0.1
0.2
0.2
0.7
' Fe,
mg/l
<0.1
0.2
:" 0.3
8.0 .
Ni,- Pb, Zn
mg/l .. mg/l mg/r
<0.1 <0.1 0.8
<0.1 <0.1 0.3
<0.1 <0.1 0.7
<0.1 0.5 0.8
Mn . . iiAg,".'
mg/l ^ > '"mg/l-:
<0.1 '• <0.1
<0.1 " <0.1
"• £
0.5 <0.1
'mg/l
0.4
0.3
0.4
0.4
-------
All samples that were investigated were collected from the individual plants at
points above any gravity separation facilities.
Results
All results are summarized in Table 14. Only the wastewarer designated 101
demonstrated a potential for requiring sedimentation. The remaining individual
wastewaters were sufficiently low in suspended solids concentrations and it would
not appear feasible to require sedimentation as pretreatment at these plant sites.
Almost all of the solids that were removed from wastewater 081 floated readily to
the surface, thus indicating a potential of flotation as pretreatment.
Two samples had sufficient quantities of floating oil to indicate the need for in-
plant control.
The integrated wastewater had an initial suspended solids concentration of 130
mg/l with a removal of 23 percent under the aforementioned settling conditions.
Two significant factors were apparent based on these bench scale studies, namely,
the solids were of a flocculent nature, and the concentrations appeared to be pH
dependent. j
BIOLOGICAL TREATMENT EVALUATION |
Secondary biological treatment is applied to reduce the concentration of organic
wastewater constituents through biochemical oxidation to a level acceptable for
discharge into a receiving body of water or to the point where tertiary treatment
can be employed effectively. Although the applicability of biological processes
for domestic wastewater treatment is well documented, bench or pilot scale
biological treatability tests should be conducted where industrial wastewaters
are involved. Such testing programs yield data which are necessary in predicting
the levels of effluent quality which can be obtained and the design factors required
to achieve these effluent quality goals.
The scope of the biological treatment evaluation using the bench scale approach
as originally proposed included only the use of batch reactors. However, it was
assumed that a more representative simulation study would be required in order
to accurately define the response of each individual wastewater to biological
treatment. Consequently, the scope was expanded to include the evaluation of
biological treatment for each industrial wastewater and the integrated composite
using continuous bench scale reactors. These studies were conducted over a
period of three months.
i
The general procedure for the treatability studies involved operating one continuous
80
-------
TABLE 14
SEDIMENTATION ANALYSES OF UNTREATED WASTEWATER
Suspen ded Sol ids
00
WASTEWATER
Oil
021
031
041
051
061
071
081
091
101
191
Initial
mg/l
180
70
80
130
110
170
210
170
750
130
Final
mg/l
180
50
70
50
80
70
60
90
120
100
Percent
Removal
0
28.6
vfafQ
61.6
27.3
58.9
71.4
47.0
84.0
23.0
OBSERVATIONS
No visible solids.
Large amount of floating oil . No solids visible .
Solids are discrete, very fine. Some floating oil
present .
Very few particles present . Appear discrete .
No samples available.
Discrete particles, very few visible .
Large fragile floes.
Most of solids floated to surface.
Many solids appeared to go into solution when pH
adjusted from 1 .1 to 7.0. Remaining particles are
discrete.
Large discrete particles . Rapid settling .
Solids became visible when pH adjusted from 2.6
to 7.0. Small floes visible after 10 minutes.
After 30 minutes large non-settling floes visible.
-------
reactor for each industrial wastewater including an integrated sample made up of
proportional volumes of the individual wastewaters. Each unit was evaluated at
three different organic loading rates for approximately three weeks or until sufficient
characterization data had been obtained at each loading condition.
Twenty-four hour composite wastewater samples were collected at the individual
industrial plants three times per week as described in Section IV. One gallon
of each sample was split off for use in the wastewater characterization program,
and the remaining volume was stored for use as feed for the biooxidation units.
Typically, the individual samples for each wastewater were accumulated for one
to two weeks in a 50 gallon drum, with each drum maintained at a pH of 2.0
or less to prevent bacterial decay. This accumulated sample was then used as feed
to the biological reactors.
Acclimation of the Biological Seed
Prior to the operation of the continuous biooxidation units, activated sludge
organisms were acclimated to the individual wastewaters. The units used for
acclimation consisted of a four-liter Erlenmeyer flask kept under a small vacuum.
The acclimated cultures were aerated by drawing prefiltered air through the
cultures. The air suction line also served as a constant level control and sludge
removal line. Excess cells were collected in a second Erlenmeyer flask which
acted as a liquid trap between the acclimation flask and main vacuum line.
Initially, the cultures were fed manually. However, after tests indicated that
viable cultures had developed, the cultures were fed continuously by means of a
Dekastaltic pump.
Several sources of seed were used to develop the acclimated organisms, including
domestic activated sludge from the City of Wilmington, the activated sludge
treatment plant operated by Hercules, Incorporated in Gibbstown, New Jersey,
and acclimated seeds maintained at the Wastewater Laboratory duPont, Chambers
Works, Deepwater, New Jersey.
Operation of Acclimation Units
Initial loading of the individual units were based upon the available information
about the individual waste streams and in each case, the seed sludge was selected
from that source which was most like the corresponding waste. During the first
days each seed culture was examined microscopically at least twice a day and
frequent adjustments were made in the rate and dilution of the waste used as feed.
After one week all cultures had stabilized, and a regular feed program was
initiated. Determinations of volatile suspended solids and oxygen uptake were made
during the acclimation period to ascertain that the acclimated seeds remained active.
A summary of the results for the individual acclimated seeds are presented in
82
-------
Table 15. The results show that all seeds were active at the completion of the
acclimation period.
Experimental Biological Reactors
The experimental apparatus used on each wastewater consisted of a continuous
reactor, a feed pump, feed and effluent bottles, and an air supply. The
primary element of each system was the biooxidation unit, a schematic of which
is shown in Figure 6. Ten of these units were obtained from BioDevelopment
Associates, Austin, Texas. Each unit has an aeration chamber with a maximum
capacity of eight liters, a two liter clarification chamber, and an adjustable
overflow weir for control of the working volume. The aeration chambers have
completely mixed flow characteristics, and settled solids from the clarification
chamber are recycled by induced hydraulic action. Air from a central supply
system was bubbled through a stone diffuser to provide dissolved oxygen and
provide mixing for the individual units.
The wastewater feed system consisted of individual feed bottles and one central
Dekastaltic pump with ten channels. Each pumping channel consists of a Tygon
tube looped around a central variable speed rotor with three roller bars. Flow
variations can be achieved by varying the tubing size and the motor speed.
The complete biological reactor system as set up in the laboratory is shown in
Figure 7.
Operating Procedures
The following basic procedures were generally followed during the treatability
studies:
(1) The previously mentioned industrial wastewater samples were accumulated in
50 gallon storage drums, one for each individual wastewater, for one to two weeks.
(2) When the necessary volume had accumulated, proportional samples were taken
from each individual drum and mixed to give an integrated wastewater that was
representative of the industrial wastestream that would be treated at the proposed
regional,treatment plant. The percentage of each individual wastewater used for
the integrated wastewater was cited previously in Section IV.
(3) The feed stock in all the storage drums was analyzed for total suspended solids
(TSS), volatile suspended solids (VSS), Five-day biochemical oxygen demand
(6005), chemical oxygen demand (COD), total organic carbon (TOC), total
Kjeldahl nitrogen (TKN), nitrite and nitrate nitrogen (NC>2 + NO3), total phosphorus,
phenols, and methylene blue active substances (MBAS).
83
-------
TABLE 15
ACTIVITY OF ACCLIMATED SEEDS
DISSOLVED OXYGEN UPTAKE
Tabulated values are mg dissolved oxygen per liter
Time
(Sec.)
0
15
30
60
180
300
420
540
600
900
(b)
VSSV '
10
7.0
6.6
6.2
5.8
4.5
3.5
2.7
1.8
1.4
_._
20
8.1
8.0
7.8
7.6
7.4
7.0
6.6
• — \
6.2
6.0
5.1
30
(d)
8.1W
8.0
7.8
7.6
7.4
7.0
6.6
6.2
6.0
5.1
40
6.2
4.8
3.0
2.7
1.6
0.9
0.4
0.2
0.1
0.0
WASTEWATER CODE
50 60 70
(c) 1 .2
0.9
0.7
0.7
0.5
0.4
0.2
0.2
0.2
0.1
7.6
7.5
7.4
7.4
7-2
6.9
6.7
6.3
6.2
5.5
80
7.5
7.4
7.3
7.2
6.8
•T
6.3
5.9
5.4
5.1
3.8
90
1.5
1.5
1.5
1.4
0.5
0.4
0.2
0.2
0.2
0.1
100
7.0
6.8
6.7
6.4
5.7
5.1
4.4
3.8
3.5
-
200
8.0
7.9
7,8
7.8
7.5
7.2
6.8
6.5
6.3
5.5
(mg/l) 3,200 1,780 1,320 1,820 1,800 2,080 2,200 1,800 2,400 1,520
(a) Composite of all wastes. (d) Same seed used for 20 and 30.
(b) Mixed liquor volatile suspended solids •
(c) No waste available.
-------
I'.--
Figure 6
FEED BOTTLE
PUMP
INFLUENT
FEED LINE
*- ADJUSTABLE
OVERFLOW
WEIR
EFFLUENT
BOTTLE
BENCH SCALE BIOLOGICAL REACTOR FLOW DIAGRAM
85
-------
BENCH SCALE BIOLOGICAL REACTORS
t
-------
(4) Each day sufficient amounts of each wastewater were removed from the
individual storage drums to serve as feed to the corresponding biooxidation unit
for the following 24 hour period. This sample was neutralized and, if necessary,
nutrients added. In some cases, dilution of the feed stock was necessary to permit
adequate control of the feeding rate. The feeding rate was measured daily.
(5) Bach day the following tests were conducted on the mixed liquor of each unit:
suspended solids, volatile suspended solids, oxygen uptake, pH, and temperature.
(6) The effluents from each unit were collected in containers and analyzed according
to the following schedule:
(a) Once a day an effluent sample was filtered and analyzed for COD and TOC .
(b) Twice a week the BOD5 of the filtered sample was measured.
(c) Once a week the filtered effluent was analyzed for TKN, NO2 + NOo,
total phosphorus, phenol, and MBAS.
(d) The carbonaceous oxygen demand of the filtered effluent was determined
once for each loading condition.
(e) Once a week the COD of settled effluent was determined.
The above procedures were modified at times according to the response of the
individual units.
Theory of Biological Treatment
When evaluating the biological treatability of wastewaters, it is important to
consider the constituents which adversely affect the performance and capacity of
the system. This is particularly true when developing design information from
bench or pilot scale studies. Although the limiting or inhibitory threshold con-
centrations of specific constituents on biological performance fluctuate, approxi-
mate values are reported in Table 16. Once those constituents which may affect
biological treatment are defined, continuous-flow and batch biological reactor
systems can be used in the laboratory to assess the treatability and predict the
process kinetics. Most pilot plant operations, however, are continuous-flow
systems. The batch analysis approach is usually limited to screening tests, seed
acclimation, and generalized estimates of organic removals, as the continuous-flow
process analyses provide a more accurate basis for predicting process kinetics and
establishing design criteria.
It is desirable to relate the biological oxidation system to a mathematical model,
87
-------
TABLE 16
PRE-OR PRIMARY TREATMENT REQUIREMENTS
Constituent
Limiting or Inhibitory
Concentration
Treatment
Suspended Solids
Oil or Grease
Heavy Metals
Alkalinity
Acidity
Organic load variation
Sulfides
Chlorides
Phenols
Ammonia
dissolved salts
>125 mg/l
>100 mg/l
< 1-10 mg/l
0.5 Ibs alkalinity as CaCO3 per Ib
BOD removed
Free mineral acidity
> 100 mg/l
>8,000-25,000 mg/l
> 70-160 mg/l
>1,600 mg/l
>16,000 mg/l
Lagooning, sedimentation, flotation
Skimming tank or separator
Precipitation or ion exchange
Neutralization for excessive alkalinity
Neutralization
Equalization
Precipitation or stripping
Dilution, deionization
Stripping, provide complete mixing
Dilution; pH adjustment and stripping
Dilution, ion exchange
-------
determining the coefficients from bench or pilot scale studies. This includes an
evaluation of substrate removal, sludge production, and oxygen requirements.
There is an increasing use of completely mixed biological systems, particularly in
the activated sludge treatment of industrial wastes. In this case, the soluble BOD
in the effluent is equal to that in the aeration tank. A material balance results in
the following relationship:
Q SQ - Q Se = dS .V (V-l)
dt
where:
SQ = raw waste COD, BOD
V = tank volume
Se = effluent COD, BOD
t = detention time
Q = flow
Substituting the simplest form of dS in terms of a retardent equation will yield the
relationship: dt
So ~Se _ „«. n (V-2)
where:
XQ = VSS undergoing aeration
K = substrate removal rate
n = exponent (for a first order approximation, n=l)
The total oxygen requirements in a biological system are related to the oxygen con-
sumed to supply energy for synthesis and the oxygen consumed for endogenous
respiration. This assumes that oxygen must be supplied to the system in order to:
(1) provide oxygen for biological organic removal (a'SrQ),
(2) provide oxygen for endogenous respiration where cells lyse and release
soluble oxidizable organic compounds (b'XaV), and
(3) provide oxygen required for chemical oxidation as measured by the
immediate oxygen demand (k°Q).
89
-------
This expression is:
RrV = a'SrQ + b'XaV + k°Q (V-3)
where:
Rr = oxygen utilization per day
V = volume of aeration basin <
a1 = fraction of substrate (BOD or COD) used for oxidation
Sr = substrate (BOD and COD) removed
Q = flow
b1 = fraction per day of VSS oxidized (oxygen basis)
Xo=av MLVSS in aeration tank
k = chemical oxygen demand coefficient (as measured
by immediate oxygen demand)
Sludge accumulation in the activated sludge system from the biological oxidation of
wastewaters can be computed using a similar approach. The components of a
mathematical relationship would include:
(1) increase in sludge attributable to influent SS (Q X j)
(2) increase in sludge due to cellular sythesis (aSrQ)
(3) decrease in sludge due to cellular oxidation or endogenous respiration
(4) decrease in sludge due to effluent SS (QXe)
The expression is:
AX = [QX.+aSrQ] - fbXaV+QXg] (V-4)
where:
AX = sludge production per day
90
-------
V = volume of aeration basin
Q = flow
a = fraction of substrate (COD, BOD) converted to new cells
Sr = substrate (BOD or COD) removal
b = fraction per day of VSS oxidized (sludge basin)
XQ = average MLVSS in aeration tank
X- = influent SS
Xe = effluent SS
A graphical solution for determining the design coefficients can be obtained by
varying organic loadings to the bench or pilot units and measuring the parametric
responses. The substrate removal rate from Equation (V-2) can be estimated by
plotting the response data in accordance with Figure 8(A) . If a non-removable
COD or BOD persists as shown in Figure 8(B), then Equation (V-2) must be
modified accordingly:
S0-Se = KSe -y
Xat (V-5)
The system oxygen requirements can be estimated by rearranging Equation (V-3):
R = a'Sr + b1
Xa Xat (V-6)
where t = ^and k°Q is neglected assuming this oxygen demand is satisfied prior to
testing. TKe a1 coefficient is taken as the slope and b1 as the intercept when plotting
the data as shown in Figure 9(A).
The synthesis sludge production is predicted by rearranging Equation (V-4) and
neglecting or accounting for the influent and effluent suspended solids:
AX =aSr -b (V-7)
~*a~ Xat
the "a" and "b" coefficients are taken as the slope and intercept values,
respectively, of the plot shown in Figure 9(B).
-------
SUBSTRATE REMOVAL RATE
St
mg/l
mg/l
•
i
S0-S«
Xat
xt
Figured
92
-------
Figure 9
OXYGEN REQUIREMENTS AND SLUDGE PRODUCTION
(S-S)
AX
Xo
L
(S0-St)
Xat
93
-------
It is to be emphasized that a key parameter in the analysis of the data is:
V (V-8)
This parameter hereafter will be referred to as the removal velocity and has the
units pounds substrate removed/pound MLVSS/day.
An equally important parameter is:
So
~X? (V-9)
This parameter hereafter referred to as the organic loading and has the units of
pounds substrate applied/pound MLVSS/day.
It should be noted that the removal velocity is approximately equal to the load
when the effluent concentration of the substrate (Se) is small.
Data Management
Because of the considerable amount of data that was generated during the course of
the treatability studies, it was essential that efficient data handling methods be
utilized from the start. The procedures were as follows: (1) basic analytical results
were recorded on typical laboratory data sheets; (2) these data were then transferred
to a standard data sheet that could be read by a key punch operator; (3) the data
were then punched on computer cards; and (4) the data were read into an IBM 360
computer and processed by a Fortran IV program.
While the studies were in progress, a simplified computer program was incorporated
for monitoring results. After the completion of the studies, the program was
expanded so that the output for each individual wastewater consisted of seven
sheets as follows:
(1) a summary of results based on BOD5
(2) a summary of results based on COD
(3) a summary of results based on TOC
(4) a summary sheet for organic removals in terms of BODe, COD, TOC,
phenols, and MBAS
(5) a summary of influent conditions
(6) a summary of filtered effluent conditions, and
(7) a summary of the mixed liquor conditions.
The computer program is outlined in Table 17.
94
-------
TABLE 17
COMPUTER PROGRAM FOR TREATABILITY STUDIES
IV G LEV ELI , MOD 4 MAIN DATE = 70120 07/26/38
DIMENSION X(16), X3(20/ 16), X5(50,5), X6(20,3), X7(50,3),
1 X4(50,16), ID3(20), IM3(20), IY3(20),ID5(50), 1X5(50), IM5(50), 106(20),
21M6(20), 1X6(20), ID7(50), IM7(50), IY7(50), ID4(50), IM4(50), IY4(50),
3DIL(50), BODIN(SO), FLO(50), T(50), CIN(50), VSS(50), SA(50),
4SLUDGE(50), DT(50), PCTB(50), PCTC(50), PCTT(50), PHENL(50), SMBA(50),
5PCTP(50), PCTM(50), TOCIN(50), CODS(50)
CODSET-1000000.
2 N3=0
13=0
N4=0
XFOUR=1.0E30
XFIVE=1 .OE-10
14=0
N5=0
15=0
N6=0
16=0
N7=0
17=0
1 READ(1,100) IS, IYR, IMO, IDAY, (X(J),J=1,16),V
ISAM=IS- 3
IF(IS ) 10,10,20
3 READ(1,101) ISI,IS2, IS3, IYR, IMO, IDAY, (X(J), J=l, 16), VI
IF(V1.NE.O.)V--V1
12 IF(IS3.NE.3) GO TO 25
20 N3=N3+1
13=13+1
IM3(I3) =IMO
ID3(I3) =IDAY
IY3(I3) =IYR
IF(X(1). NE.O.O)FLOW=X(1)
DO 21 J=l,16
X3(I3,J)=X(J)
IF(X3(I3/J))22,22,21
22 X3(I3,J)=1.0E20
21 CONTINUE
GOTO 3
95
-------
TABLE 17 (continued)
25 IF(IS3.NE.5) GO TO 30
N5=N5+1
15=15+1
IM5(I5)=IMO
ID5(I5)=IDAY
IY5(I5)=IYR
X5(I5,1)=X(2)
X5(I5,2)= X(3)
X5(I5,3)=X(4)
X5(I5/4)=X(5)
IF(X(5).NE.O.)XFIVE=X(5)
X5(I5/5)=X(10)
DO 26 J=l,5
IF(X5(I5,J))27,27,26
27 X5(I5/J)=1.0E20
26 CONTINUE
GO TO 3
30 IF(IS3.NE.6) GO TO 35
CODSET=X(8)
IF(CODSET.EQ.O.O)CODSET=1 .OE 10
31 GO TO 3
35 IF(IS3.NE.7) GO TO 40
N7=N7+1
17=17+1
X7(I7,1) =X(1)
X7(I7,2! =-X(4)
X7(I7,3) =-X(5)
DO 36 J=2,3
IF(X7(l7,J))37/37/36
37 X7(I7,J)=1.0E10
36 CONTINUE
GO TO 3
40 N4=N4+1
I4=|4+l
PHENL(N4) = X3(«3,15)
BODIN(N4)= X3(I3,6)
DIL(N4)=X3(I3/11)
FLO(N4)=FLOW
VOL(N4)=V
TOCIN(N4)=X3(I3,9)
CIN(N4)=X3(I3,8)
CODS(N4)=CODSET
VSS(N4)=XFIVE
SMBA(N4)=X3(I3/16)
96
-------
TABLE 1/(continued)
IM4(I4) = IMO
IY 4(14) =IYR
ID4(I4) =IDAY
IF(X(6).NE.O.)XFOUR=X(6)
DO 41 J=*,16
X4(I4,J)=X(J)
IF(X4(I4,J))42,42,41
42 X4(I4/J)=1.0E20
41 CONTINUE
X4(I4,4)=0.
X4(I4,5)=0.
IF(I4.NE.1) GO TO 43
WRITE(3,200) I SAM
WRITE(3,205)
WRITE (3,202)
43 DT(N4)=VOL(N4)/FLO(N4)
ALOAD =(FLOW * X3(N3,6) / (V* XFIVE)
REMV KFLOW * (X3(N3/6) - XFOUR) ) / (V* XFIVE)
PCTB(N4) =100.*(X3(N3,6)-X4(N4,6))/X3(N3,6)
SLUDGE(N4) = X7(N7,1) *X7(N7,3) /1000.
SA(N4) =(X7(N7,1) * X7(N7,3)) /(V*XFIVE)
IF(X7(N7,1).EQ.O.) SA(N4)=1 .OE10
IF(X4(N4/6) .LT. 1 .OE05)GOT044
PCTB(N4)=1000000.
CODSET=1000000.
GOT03
44 WRITE(3/201) IMO/IDAY/IYR,V/X3(N3/1)/ DT(N4)7 X3(N3/6)/ X4(N4,6),
1ALOAD,REMV, PCTB(N4)7 X4(N4,7)f SLUDGE(N4), SA(N4),VSS(N4)
CODS ET=1000000.
GO TO 3
11 WRITE(3/271)ISAM
WRITE(3,207)
WRITE(3/202)
DO 71 I=1,N4
ALOAD=(FLO(I) * CIN(I))/(VOL(I) * VSS (I))
REMV =(FLO(I) *(CIN(l)-X4(lf8))/(VOL(l)*VSS(l) )
PCTC(I)=100. *(CIN(D-X4d,8))/CIN(l)
IF(CIN(I) .LT.l .OE05)GOT072
GOT071
72 IF(X4( 1,8) .IT. 1 .OE05)GOT070
PCTC(I)=1000000.
GOT071
70 WRITE(3/270)IM4(I)/
97
-------
TABLE 1/(continued)
1X4(1,8),ALOAD,REVM,PCTC(I),CODS(I), SLUDGE (I),SA(I) ,
71 CONTINUE
206 FORMAT(14X,'L',8X,'L/DAY D AYS', 6X,'MG/L',6X,'MG/L',46X,
TG/DAY G/G*DAY MG/L1)
WRITE(3,281) ISAM
WRITE(3,206)
WRIT E(3,202) ^
DO 81 1=1 ,N4
PCTT(I)=100. *(TOCIN(I)-X4(I,9))/TOCIN(I)
ALOAD=(FLO(I)*TOCIN(I))/(VOL(I)*VSS(Q)
REMV=(FLO(I)*(TOCIN(I)-X4(I,9)))/(VOL(I)*VSS(I) )
IF(TOCIN(l).LT.l .OE05)GOT082
REMV= 1000000.
PCTT( l)=l 000000.
GOT081
82 IF(X4(I/9).GT.1.0E05)GOT081
80 WRITE(3,280) IM4(I),ID4( I),IY4(I),VOL(I),FLO(I),DT(I),TOCIN(I),
1 X4a,9),ALOAD,REMV,PCTT(l), SLUDGE(l),SA(i),VSS(l)
81 CONTINUE
WRITE(3,291) ISAM
DO 90 1=1, N4
PCTP(I)=ICO.*(PHENL(I)-X4(I,15))/PHENL(I)
IF(PHENL(I).GT.1.0E05)PCTP(I)=1000000.
PCTM(I)=100.*(SMBA(I) -X4(l/ 16))/SMBA(I)
IF(SMBA(I) .GT.l .OE05)PCTM(I)=1000000.
90 WRITE(3,290) IM4(I)/ID4(I)/IY4(I)/DIL(I)/BODIN(I)/CIN(I)/TOCIN(I).
1 PHENL (I) SMBA (I), X4(l,6), (X4(I/J)/ J=8,9), X4(l/15)/ X4(l,16)/
2 PGTB(I),PCTC(I),PCTT(I)/PCTP(I),PCTM(I)
290 FORMAT(1X/I2,2X/I2/1X,I2/5X,F3,0/5X/ 3(F5.0.1X)/F7.3,1X/F4.1.
16X/3(F5.0/1X)/F7.3/1X/F4.1X/F4J/6X/4(F5.1/1X)/1X/F5.1)
291 FORMAT(1H1 , *TREATABILITY STUDY FOR WASTEWATER ',I3/
I1 SUMMARY OF ORGANIC REMOVALS1/
270X,'FILTERED1/
312X,'DILUTION INFLUENT CONCENTRATIONS', 12X,'EFFLUENT1,
42X 'CONCENTRATIONS', 15X,'PERCENT REMOVALS'/ISX'OF'/
5' MO DAY YR RAW WASTE BOD COD TOC PHENOL MBAS',7X,
6'BOD COD TOC PHENOL MBAS',7X,'BOD COD TOC PHENOL MBAS'/
711X,'WATER/WASTE MG/L MG/L MGA MG/L MG/L1
87X,'MG/L MG/L MG/L MG/L1//)
205 FORMAT(14X,'L',8X,'L/DAY DAYS',6X,'MG/L,6X,'MG/L',36X,
I'MG/L'^X/G/DAY G/G*DAY MG/L1)
207 FORMAT(14X,'L',8X,'L/DAY DAYSVdX/MG/L'^X
1'(FILTERED)',3X,'MG/L1,6X/G/DAY G/G*DAY MG/L1)
WRITE(3,230)ISAM
98
-------
TABLE 17(continued)
WRITE(3,231)
DO 53 13= 1,N3
53 WRITE(3,224) IM3(I3), IDS (13), IY3(I3),
1X3(13,6),
2X3(13,8),X3(I3,9),
3(X3(I3,J),J=12,16),X3(I3,11)
WRITE(3,223) ISAM
WRITE(3,232)
DO 60 14=1, N4
60 WRITE(3,229) IM4(I4),ID4(I4),IY4(I4),X4(I4,6),
1X4(I4,8),X4(I4,9),
2(X4
-------
TABLE 1/(continued)
230 FORMAT(1H1, 'TREATABILITY STUDY FOR WASTEWATER ',I3/
T SUMMARY OF INFLUENT CONDITIONS1/
2' ALL DATA EXPRESSED AS MG/L EXCEPT AS NOTED1/)
223 FORMAT (1H1, 'TREATABILITY STUDY FOR WASTEWATER', 13/
T SUMMARY OF FILTERED EFFLUENT CONDITIONS'/
2' ALL DATA EXPRESSED AS MGA'/)
231 FORMAT(42X, 'TKN NO2 + NO3 TOTAL PHOS1, 22X,'DILUTION'/
T MO DAY YR', 3X, ' BODS'^X/COD'^X/TOC,
28X,'N1,9X,IN',9X,IPI,7X,'PHENOL , MBA WATER/WASTE1//)
232 FORMAT(42X, 'TKN NO2 + NO3 TOTAL PHOS1, 22X,1 '/
T MO DAY YR',3X 'BODS'^X/COD'^X/TOC1,
28X/N1, 9X,1NI,9X/'PI,7X,'PHENOL MBA '//)
240 FORMAT(1 HI,'TREATABILITY STUDY FOR WASTEWATER',13)
271 FORMAT( 1H1,'TREATABILITY STUDY FOR WASTEWATER1, I3/
I1 SUMMARY OF RESULTS BASED ON COD1/
2' LOADING AND REMOVAL VELOCITY ARE EXPRESSED AS LABS COD / LBS MLV
3SS * DAY1//
451X/FILTERED1, 23X,'PERCENT SETTLED1/
511X, 'VOLUME1,13X,'DETENTION INFLUENT EFFLUENT1,
613X, 'REMOVAL REMOVAL EFFLUENT SLUDGE GROWTH1/
71 MO DAY YR OF UNIT FLOW RATE TIME COD COD LOAD
SING VELOCITY OF COD COD PRODUCTION RATE',5X,'MLVSS')
281 FORMAT(1H1,'TREATABILTIY STUDY FOR WASTEWATER1,13/
I1 SUMMARY OF RESULTS BASED ON TOC'/
2' LOADING AND REMOVAL VELOCITY ARE EXPRESSED AS LBS TOC / LBS MLV
3SS * DAY'//
451X, 'FILTERED', 23X,1 PERCENT1/
511X, 'VOLUME1,13X,1 DETENTION INFLUENT EFFLUENT1,
613X, 'REMOVAL REMOVAL SLUDGE GROWTH1/
7' MO DAY YR OF UNIT FLOW RATE TIME TOC TOC LOAD
SING VELOCITY OF TOC PRODUCTION RATE',5X,'MLVSS')
270 FORMAT(I3,2X,I2,I3,2X,F5,3,5X,F6,3,4X/F5.2,5X,F5.0,5X,F5.0,5X,
1F5.2,5X, F5.2,6X, F4.1,5X, F5.0,4X, F6.3,5X, F5.3,5X, F5.0)
280 FORMAT(I3,2X, 12,13,2X, F5.3,5X, F6.3,4X, F5.2,5X, F5.0,5X, F5.0,5X,
1F5.2,5X,F5.2,6X,F4.1,5X,5X ,4X,F6.3,5X,F5.3,5X,F5.0)
10 STOP
END
100
-------
Results of Bench Scale Biological Reactor Studies
Identification of Participants^
As agreed at the start of the laboratory investigations, the results for the
individual participants are identified only by code. For the treatability studies,
the code was the number of the individual industry plus 200: i .e., the code
number of industry 40 would be 240. The code used for the integrated wastewater is
510.
Participants Excluded from the Study
No individual treatability studies were conducted on the wastewater from Houdry
because the characterization studies had indicated that the BOD5 concentration
was too low for efficient biological treatment.
B. F. Goodrich was also excluded because their plant was not producing a
wastewater at the time of the studies.
Computer Output
The summary of results provided by the computer program for each wastewater
investigated is not included in this Report, but was submitted as a separate task
report.
Substrate Removal
The percent removal for both BOD^ and COD for the integrated wastewater (510)
is plotted versus the removal velocity in Figure 10. The same results for the
individual participants are presented in Figures 11 through 18. All results are based
on filtered effluent samples.
All of the wastewaters investigated resulted in BOD5 removals in excess of 90
percent at low loadings. (Note: loading is approximately equal to the removal
velocity in the lower ranges because of the low effluent concentration of the
substrate. At higher loadings the effluent concentration increases and therefore
the removal velocity begins to become significantly lower than the loading.)
At intermediate and high loadings, results for the individual units varied
substantially. Wastewaters 240, 260, 290, and 300 continued to have BOD5
removals negr or in excess of 90 percent at loadings of approximately 0.5 to 0.6
Ibs BOD5/lb MLVSS/day. Wastewaters 220, 230, and 280 experienced fairly uniform
decreases in performance as the loading was increased, and the unit treating waste-
water 210 could not be operated satisfactorily at loadings above approximately 0.3.
101
-------
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510
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The results for the-integrated wasrewater (510) indicated the removals in excess
of 90 percent could be achieved at loadings as high as 0,70. At higher loadings
the removals fell off uniform!ly.
Effluent First State Oxygen. Demand (LJ
The La concentration in the filtered effluent for each of the individual waste-
waters at the various loadings are summarized in Table 18. For the integrated
wastewater (510), the data indicated that the effluent La would be 36 mg/l at a
loading of 0.50. this would result in 310 pounds of first stage oxygen demand
being discharged in the effluent from a regional plant for each million gallons
treated.
Substrate Removal Rate .'
Effluent concentrations for both BOD«j and COD versus the removal velocity for
the integrated wastewater (510) are plotted in Figure 19. The resulting substrate
removal rate K, which is the inverse of the slope of the line of best fit, is 0.0316
using BODs as the basis and 0.00725 based on COD. In the latter case, there
is an extrapolated, non-degradeble COD concentration in the effluent of
approximately 30 mg/l, although the actual COD residual value will probably be
higher. On the basis of extrapolation, the factor "y" in the previously derived
equation for substrate removal (Equation V-5) is 0.2. In the case of BODs, there
is negligible residual concentration in the effluent and therefore y approximates 0.
To demonstrate the use of the substrate removal equation, assume it was desirable
to maintain an effluent BOD5 concentration of 15 mg/l. Using the above
coefficients
SQ."Se= KSe-v =(0.0316) (15) - 0 = Q.475 lbs BOD5 Removed
V lb MLVSS day
Therefore the required removal velocity is 0.475. Assuming also that the influent
BODs 'S 300 mg/l and the MLVSS concentration in the aeration basin will be
maintained at 2000 mg/l, the required detention time is as follows:
S°/$e = 0.475
300-15 = 0.475
2000 t
t = 0.3 days = 7.2 hours
111
-------
TABLE 18
EFFLUENT FIRST STAGE OXYGEN DEMAND FOR
INDIVIDUAL WASTEWATERS AT VARIOUS LOADINGS'
(a)
(b)
(b) Removal LQ Removal La Removal
Waitewofer Load Velocity mg/l Load Velocity mg/l Load Velocity mg/l
510
210
220
230
240
260
280
290
300
0*27
0.26
0.15
0.08
0.14
0;*29
0.57
0.22
0.31
0.26
0.20
0.14
0.07
0.13
0.29
0.51
0.21
0.29
7
125
6
9
6
4
42
64
30.
0.50
0.23
0.19
0.60
0.26
0.68
0.85
0.47
0.19
0.16
0.56
0.26
•
0.62
0.26
36 0.70
16 0.37
10
47 0.82
13
200
3400
0.63 71
0.27 31
0.58 105
(a) First stage oxygen demand (LQ) determined in accordance with DRBC
publication dated June 1968.
(b) The units for load and removal velocity are Ibs BOD^/lb MLVSS/day,
112
-------
Therefore the required detention time for the assumed conditions, namely, 95
percent BOD5 removal, is 7.2 hours. Scale-up factors and temperature factors
dictate a longer detention requirement fora full-scale system, however.
It is to be noted that these results are based on filtered effluent samples. Also,
as can be seen in Figure 19, Equation V-2 for BOD5 applies only to removal
velocities below 0.60. Above this point, the data were scattered.
Sludge Production and Oxygen Requirements
Oxygen uptake rates and sludge growth rates are plotted versus the BOD5 removal
velocity for each wastewater in Figures 20 through 28. The same data using COD
as a basis for the removal velocity are presented in Figures 29 through 37.
These graphs were used in determining the kinetic coefficients in the previously
derived mathematical expressions for sludge production and oxygen requirements.
The resulting coefficients are summarized in Table 19 for the BODg basis and the
COD basis.
Sludge Production
In some cases, particularly for wastewaters 210, 230, and 300 the scatter of
points was such that the coefficients could not be determined. The data for the
remaining wastewaters indicated that the factor "a", which is the amount of
biological sludge produced for each pound of substrate removed, was consistently
low. The "a" value of 0.19 derived from the combined wastewater treatability
study is significantly lower than that normally experienced for municipal and
industrial wastewaters. It should be recognized that the reliability of sludge
production values from bench scale studies is low because of the physical limitations
of the testing approach.
However, more definitive data was developed from the subsequent pilot plant
studies as described in Section VI, indicative that the sludge production rate is in
fact lower than that normally reported. Based on the data from the pilot plant
studies, it is anticipated that approximately 200 to 300 Ibs of biological sludge
per day per MGD will be generated.
Oxygen Requirements
The data cited in Table 19 indicate oxygen utilization coefficients which are
similar to those normally reported for biological treatment of industrial wastewaters.
Applying Equation (V-3), it is estimated that approximately 1,800 Ibs of oxygen
would be required per MGD treated. The subsequent pilot plant studies described
in Section VI closely substantiate this data although somewhat higher values were
113
-------
FILTERED EFFLUENT CONCENTRATIONS FOR THE INTEGRATED WASTEWATER
100 r-
90
80
_ 70
*v
O»
E
. 60
in
Q
O
1X1 50
UJ
13
li_
u.
40
30
20
10
D
D
0.0 0.2
BOD
_L
I
D
0.4
0.6
0.8
REMOVAL VELOCITY
1.0 1.2 1.4 1.6
LB SUBSTRATE REMOVED
LB MLVSS • DAY
1.8
D
300^
O>
O
8-
ZOO
UJ
u.
u.
UJ
100
2.0
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTE WATER 510
Oi
g
OB
cc
x
t
O
K
O.SOf—
0.45
O.40
0.35
0.30
0.25
0.20
0.15
O.IO
O.OS
a
O.OO
o.o
O.2
B
D.
a
I
0.4 as
REMOVAL VELOCITY
O.8
LB
i.o
REMOVED
I.Z
LB MLVSS-DAY
-i 1.0
0.9
o.t
O.T
0.5 m
O.4
CO
0.3 CO
1.4
OJt
0.1
O.O
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 210
CD
>-
O
DC
X
O
oc
0.10 r-
0.09
0.08
O.O7
0.06
0.09
0.04
0.03
0.02
0.01
0.00
1
0.0
0.2
0.4 a6
REMOVAL VELOCITY
0.8 1.0
LB BOD^ REMOVED
LB MLVSS-DAY
1.2
1.4
—i i.o
O.9
0.8
0.7
0.8
O
X
m
0.5 m
00
0.4 7
to
0.9 cn
|
0.2
0.1
CD
0.0
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 220
CD
0.10 i—
0.09
O.O8
0.0?
CD
o
oc
0.06
O.O5
0.04
0.03
0.02
0.01
0.00
0.0
0.2
0.4
REMOVAL VELOCITY LB B00*^ REMOVED
REMOVAL VELOCITY LQ M|_vss . DAY
1.4
-1 1.0
0.9
0.8
O.T
o..
8
2
0.9 m
CD
° « 2
w
0.3 C/»
I
0.8
O.I
0.0
O>
-------
a>
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 230
5
CO
0.10 r-
O.O9
O.O8
0.07
0.06
0.09
ec
x
^^
§
0.04
0.05
O.O2
0.01
0
0.00 ' • •
i
i
O.O
0.2
0.4 ae
REMOVAL VELOCITY
0.8 1.0
LB BODjt
LB MLVSS-DAY
1.2
1.4
-il.O
O.9
8
0.6
X
as PI
O4
a»
as co
s
0.1
0.0
-------
"Q
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 240
0.10 r-
o.oo
0.0
0.2
0.4
REMOVAL VELOCITY
0.8 1.0 1.2
LB BODs REMOVED
LB MLVSS • DAY
1.4
o.o
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 260
8
O
CQ
O
or
0.10 i—
O.O9
0.08
0.07
0.06
0.09
O.04
0.03
0.02
0.01
0.00
0.0
0.2
0.4
0.6
REMOVAL VELOCITY
0.8 1.0
LB BOD*REMOVED
LB MLVSS • DAY
1.4
—I 1.0
0.0
Cn
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 280
s
o
•
CO
o
or
0.10 i—
0.09 -
0.08 -
0.07
0.0«
O.OS
0.04
O.O3
O.02
O.OI
O.OO
0.0
0.2
D
I
0.4 0.6
REMOVAL VELOCITY
0.8 1.0
LB BOD* REMOVED
LB MLVSS • DAY
1.2
-I 1-0
0.9
O.B
1.4
O
X
0.7 cT
O.C
0.5 m
0.4 5
CO
as co
6
O.I
O.O
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 290
m
00
0.10 i—
O.O9
O.O8
O.O7
0.06
0.09
0.2
0.4
0.6
0.8
1.0
1.2
REMOVAL VELOCITY LB BOD* REMOVED
REMOVAL VELOCITY LB MLVSS . DAY
1.4
—1 1.0
0.9
O.8
o
x
0-7 O
m
0.6 S
o.s m
0.4 5
0.3
I
O.2
O.I
0.0
CD
-------
hO
CO
DETERMINATION OF KINETIC COEFFICIENTS BASED ON BOD5
FOR WASTEWATER 300
0.20 i-
0.16
O.IC
0.14
0.12
O.IO
0.06
0.06
0.04
O.O2
m
0.2
0.4 a«
REMOVAL VELOCITY
0.8 1.0
LB BOO*REMOVED
LB MLVSS-OAY
1.2
1.4
—I 1-0
0.9
0.6
O.T
O.6
O.S
0.4
O
X
O
0.3 C/>
i
0.2
O.I
O.O
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 510
0.5O|—
0.49 -
0.05 -
0.00
0.0
REMOVAL VELOCITY LB COP REMOVED
REMOVAL VELOCITY LB M|_vss . DAY
0.0
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 210
00
or
i
O.IO i—
O.09 -
0.08 -
0.07 -
os
O.O9
O.O4
O
or
O 0.03
0.02
0.01
0.00
0.0
0.2
D
0.4
D
D
0.6
REMOVAL VELOCITY
0.8 1.0
LB COD REMOVED
LB MLVSS • DAY
1.2
1.4
—i i.o
0.9
0.8
o.r
0.6
O
x
-<
m
x
0.9 m
o»
O.4
CO
0.3 CO
0.2
O.I
0.0
ro
CQ
co
o
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 220
O.IO
0.09
O.08
. 0.07
IV
o
00 V
-1 ^ 0.06
m
tf
5 0.05
.•••••••• oc
X
£" O.04
O
cc
» 0.03
0.02
O.OI
^\ ^^f%
p. —
-
_ — •
_ _
_ _
— . —
*— i— i D —
U D
— • • —
o. «• a
^^^F ^^^ ^H^
(P °
D D
— —
i~ ~~ i . « i T i i i
I.O
...
0.8
O
X
O-7 O
PI
z
0.8 =5
X
o.s m
£
o * x E
p OD
to O
0.3 Cfliw
|
0.2
0.1
M A
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
•••••••-•• ii ii ii •
nriutnvAi vn nriTY LB COD REMOVED
REMOVAL VELOCITY LB ^^^ . DAy
CO
(D
CO
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 230
0.10 i—
-i 1.0
0.09 -
- 0.9
CE.
0.08
0.07
o.o«
0.8
0.7
0.9
O
X
m
K>
•SI
K.
X
O
DC
o.os
O.O4
0.03
0.02
0.5 1*1
D
0.4
CD
CO
0.9 CO
£
0.2
O.OI
D
O.I
O.OO
0.0
0.4 0.6 0.8 1.0
REMOVAL VELOCITY L.SB Cfff
,2
|4
0.0
CQ
i
-------
KJ
00
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 240
i
0)
o
IT
O.IO r-
O.O9
0.08
O.O7
0.06
0.05
0.04
0.03
0.02
0.01
0.00
0.0
0.2
0.6
REMOVAL VELOCITY
0.8 1.0
LB COD REMOVED
LB MLVSS • DAY
1.2
1.4
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 260
O.IO i—
K>
0.01 -
0.00
0.0
0.2
0.4
0.6
REMOVAL VELOCITY
0.8 I.O
LB COD REMOVED
LB MLVSS' DAY
1.4
0.0
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 280
m
c
X
o
oc.
O.IO i—
O.09
0.08
0.07
O.O8
0.09
0.04
0.03
0.02
0.01
O.OO
0.0
D
0.2
D D
0.6
0.8
1.0
1.2
REMOVAL VCLOCITYLB COD REMOVED
REMOVAL VELOCITY LB MLVSS . DAY
1.4
—i 1.0
0.9
0.8
0.7
0.8
O
X
•<
ni
*
0.9 m
0.4 2
CO
0.3 en
6
0.2
O.I
0.0
CD
-------
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 290
O.IO i-
o.ot -
O.OO
0.0
0.2
REMOVAL VELOCITY
o.a
LB
1.0 1.2
COD REMOVED
LB MLVSS-OAY
1.4
0.0
CO
c
-------
CO
to
DETERMINATION OF KINETIC COEFFICIENTS BASED ON COD
FOR WASTEWATER 300
DO
5
o
UJ
I
or
0.2Oi—
0.18
0.16
0.14
a12
0.10
0.08
0.06
O.O4
O.02
0.00
0.0
D
D
DO
3 a
a
0.2
0.4
0.8
REMOVAL VELOCITY
REMOVAL VELOCITY
0.8 1.0
LB COD REMOVED
LB MLVSS • DAY
1.2
1.4
—i i.o
0.9
0.8
O.T
O
X
-<
m
a. %
0.5 m
£
0.4 9
CO
0.3 CO
6
0.2
0.1
0.0
CD
-------
TABLE 19
SUMMARY OF KINETIC COEFFICIENTS
(BOD5 BASIS)
_ _ b _ o| _ b1
Ibs sludge Ibs sludge oxidized Ibs oxygen reg'd Ibs oxygen reg'd
Wastewdter Ibs BOD5 removed Ibs sludge day Ibs BODg removed Ibs sludge oxidized day
510 0.19 0.06 0.63 6.06
2 TO * * * *
220 0.18 0.025 0.75 0.13
230 0 0 * *
240 0.02 0.003 0.67 0.06
260 0.05 0.01 0.28 0.11
280 0.08 0.015 * *
290 0.05 0.01 0.37 0.13
300 * * * *
*Data did not fit a straight line
SUMMARY OF KINETIC COEFFICIENTS
(COD BASIS)
Wastewater
510
210
220
230
240
260
280
290
300
a
Ibs sludge
Ibs COD removed
0.06
0.00
*
0
0.006
0.04
0.004
0.10
*
b
Ibs sludge oxidized
Ibs sludge day
0.025
0.00
*
0
0.002
0.07
0.001
0.045
*
a1
Ibs oxygen reg'd
Ibs COD removed \
0.25
*
*
*
0.33
*
*
0.40
*
b1
Ibs oxygen reg'd
fes sludge oxidized
0.13
*
*
*
0.04
*
*
0.05
*
day
*Data did not fit a straight line.
133
-------
determined .
Summary
(1) The main conclusion to be drawn from the treatabiiity studies is that all
wastewaters investigated had BOD5 removal (based on filtered effluent samples)
in excess of 90 percent at loadings of approximately 0.20 pounds BOD^/pound
MLVSS/day. Wastewaters 240, 260, 290, and 300 continued to have BOD5
removals in excess of 90 percent at loadings up to 0.60 pounds BOD5/pounol MLVSS/
day. The results for the integrated wastewater indicated BOD5 removals in excess
of 95 percent at a loading of approximately 0.25 pounds BOD5/pound MLVSS/day
and removals above 90 percent at loadings up to 0.70 pounds BOD^/pound MLVSS/
day. The predicted effluent quality based on bench scale tests is presented in
Section VI11, Table 54.
(2) Using the results for the treatability study for the integrated wastewater based
on filtered effluent data, the following parameters would be applicable to the
theoretical design of a regional plant.
Assume: Influent soluble BOD5 = 300 mg/l
Effluent soluble BOD5 = 15 mg/l
MLVSS= 2000 mg/l
Loading = 0.50 Ibs BODylb MLVSS/day
Removal velocity = 0.475 Ibs BOD^lb MLVSS/day
i
Required: Detention time = 0.3 days (no scale-up applied) !
Oxygen required = 1,800 Ibs/day/MGD (oxygen basis only)
Volatile sludge produced = 300 - 600 Ibs/day/MGD
Effluent La = 36 mg/l
= 310 Ibs/MGD
These results are only approximate and were modified as required based on subsequently
obtained pilot plant results.
(3) The treatability studies indicated that with the possible exception of color and
bioassay requirements, the activated sludge process could be used to treat the
industrial wastewaters involved in the study to the quality level tentatively pro-
posed by the DRBC. The true color of the industrial wastewaters, particularly the
integrated wastewater, was not reduced significantly by biological treatment.
Although the concentration of MBAS in the integrated wastewater effluent exceeded
10 mg/l, the data indicated that the high concentration was the result of inter-
ferences rather than detergents. Also, phenol removals for the integrated waste-
water were in excess of 90 percent and resulted in an effluent concentration of
approximately 0.30 mg/l.
134
-------
Oxygen Transfer Studies
In this study the oxygen transfer parameters were determined for the integrated
wastewater using both diffused air and mechanical aeration methods. The
settled effluent from the bench scale reactor treating the integrated wastewater
was chosen for analysis because its characteristics more closely resemble the
fluid in an aeration basin than would the raw waste. It was decided not to
conduct oxygen transfer experiments using the mixed liquor from the reactor
because of the difficulty in establishing a true oxygen uptake by the activated
sludge organisms.
These results are based on bench scale studies as described below. Subsequent
analyses were conducted in the pilot plant operation using an "in situ" approach as
described in Section VI.
Procedure
]. The aeration vessel was filled with six liters of tap water and the temperature
recorded.
2. The solution was deoxygenated by the addition of a sodium sulfite solution
containing a cobalt chloride catalyst.
3. The liquid was reaerated, measuring the dissolved oxygen concentrations at
various time intervals. Reaeration was achieved using both sparged compressed
air and a bench scale mechanical aerator.
4. The oxygen deficit versus time was plotted on semi-log paper.
5. The coeficients K|_a, &, and B were calculated based on the following
equations:
dc= KLa(Cs-C) (V-10)
dt
KLa=J ln(Cs-C0)/(Cs-Ct) (V-ll)
B = Cs (Waste) / Cs (Water) (V-12)
a = KLa (Waste) / KLO (Water) (V-13)
135
-------
where:
dc _ Rate of change of the dissolved oxygen concentration.
dT~
K|_a = Overall oxygen transfer coefficient, (hour)
T = Time of aeration, hour.
Cs = Saturation concentration of oxygen in liquid, mg/l.
Co = Concentration of oxygen in liquid at T = 0, mg/l
Cf = Concentration of oxygen in liquid at time T, mg/l
6. Steps 1 - 5 were repeated using an equal volume of settled effluent from the
reactor treating the integrated wastewater.
7. Steps 1 - 6 were repeated using mechanical aeration equipment.
Results
The results of the oxygen transfer studies and the calculated coefficients are
summarized in Table 20. The plots from which the determinations were made are
shown in Figures 38 through 43. These include both the diffused and mechanical
aeration tests.
As noted in Table 20, the oxygen transfer coefficient, OL, decreased with an increase
in organic loading for the diffused air studies. This is to be expected as more
dissolved organic constituents are present in the effluent at the higher loading, and
this will tend to reduce the oxygen transfer from the gas phase to the liquid phase
across the liquid film. However, the K|_a and a values derived from the mechanical
aeration studies were rather erratic and it is recommended that these values be
discarded as confirmatory pilot plant tests were conducted.
Zone Settling Analyses
Settling analyses were conducted on the mixed liquor from each of the bench
scale reactors. For the units treating the individual wastewaters, the settling
analyses were performed basically to determine the relative settleability of the
individual sludges.
Data for the unit treating the integrated wastewater were further analyzed to
136
-------
TABLE 20
SUMMARY OF OXYGEN TRANSFER PARAMETERS
Bio-Reactor
Loading
Ib BOD5
Ib MLVSS/Day
-0.25
-0.50
-1.00
Diffused Air
KLa
Wastewater (a)
hr-'
9.4
6.5
3.2(b)
Water
hr"'
12.0
8.5
5.2
^
21
21
25
a
1.27
0.92
0.61
KLCI
Wastewater (a)
hr~'
Data Inconsistent
4.4
7. l(b)
Mechanical Aeration
Water
TFT
2.8
3.2
Temp
°C
21
25
a
1.55
2.20
(a) Experiments conducted on the effluents from the Bio-Reactors at the various loadings.
(b) KLa corrected to 25°C by formula KLa(J1) = K|_a(T2) }
-------
10
OXYGEN TRANSFER BY DIFFUSED AERATION
LOAD » 0.25 LB BOD5/LB MLVSS/DAY
5
§ 4
x
o
Water at 21* C
Waste at 21° C
6 8
TIME (minutes)
10
12
14
-------
10
OXYGEN TRANSFER BY MECHANICAL AERATION
LOAD « 0.25 LB BOD5/LB MLVSS/DAY
o
LI.
ui
o
o
x
o
5
4
Water at 20° C
-Waste at 20.5° C
10
15 20
TIME (minutes)
25
30
35
CO
w
*o
-------
10
OXYGEN TRANSFER BY DIFFUSED AERATION
LOAD » 0.5 LB BOD5/LB MLVSS/DAY
,5 5
0 4
UL
UJ
UJ
52
2
6 8
TIME (minutes)
10
12
14
-------
10
OXYGEN TRANSFER BY MECHANICAL AERATION
LOAD g 0.5 LB BOD5/LB MLVSS/DAY
a*
£ 5
O 4
UJ
O
UJ
CD
I 3
Water at 21° C
Wasteat2l°C
6 8
TIME (minutes)
10
14
-------
10
OXYGEN TRANSFER BY DIFFUSED AERATION
LOAD ss 1.0 LB BOD5/LB MLVSS/DAY
~ 5
t
O 4
k.
Ul
Waste at 18.5° C
Water at 25°
8
10
TIME (minutes)
12
14
-------
to
10
OXYGEN TRANSFER BY MECHANICAL AERATION
LOAD g 1.0 LB BOD5/LB MLVSS/DAY
Water at 25° C
o>
£ 5
O 4
u_
UJ
o -,
UJ
o
X
Waste at I6.5°C
6 8
TIME (minutes)
10
12
14
-------
determine the preliminary design parameters for secondary clarification.
Secondary clarification of activated sludge involvestwo requirements: clarification
of the liquid overflow; and thickening of the sludge underflow.
For clarification, the rise velocity of the liquid overflowing the tank must be
less than the zone settling velocity of the activated sludge. Thickening requires
that sufficient time be provided for the sludge to compress to the desired con-
centration. Both criteria must be considered in analyzing the results of sludge ••
settling analyses.
Procedure
1 . One liter of mixed liquor from each biological reactor was placed in a one
liter graduated cylinder. Samples were also taken for suspended solids analyses.
2. Zone settling curves were then determined by measuring and plotting the
sludge interface height versus time for each individual unit.
3. The results for the integrated wastewater were converted to a plot of inter-
face settling velocity versus the solids concentration by taking the slope of the
curve from step 2 at various times and calculating the resulting solids concentration
at that time. The allowable overflow rate in gpd/sq ft for various inlet con-
centrations of solids can then be determined by multiplying the zone settling velocity in
by (24 hr/day) (7.48 gal/cu ft) .
4. The allowable overflow rate for the integrated wastewater based on sludge
thickening was determined by the equations presented as follows:
UA ~-!y-_ x 106 |b/cu ft (V-14)
^o H0 62.4
(V-15)
OR = _] - x Qr^o x IP6 ib/aa|
UAC0 Co 8.33
where:
UA = unit area, sq ft - day/Ib
OR = overflow rate, gpd/sq ft
Co = initial concentration of suspended solids, ppm
Cy = underflow concentration of suspended solids, ppm
Ho = initial height of the mixed liquor in the graduated
cylinder- 1.15 ft (13.8 in).
Hy = height of the sludge layer at the desired underflow concentration
Ty = time required to reach C and H
144
-------
Results
The zone settling curves from the individual industrial biological reactors at loadings
of 0.25, 0.50, and 1.0 Ibs BODs/lb MLVSS/day are presented in Figures 44, 45,
and 46 respectively. These data indicate good settling of sludges based on the batch
sludge settling approach. It should be recognized, however, that prototype clari-
fiers exhibit different characteristics than what might be observed in a graduated
cylinder. However, these results do indicate good biological solids - liquid
separation and offer some basis for estimating the design overflow rates.
The zone settling curves for the biological reactors treating the integrated industrial
wastewater at each of the three loadings are summarized in Figure 47. These results
have been further analyzed by taking the slope of the curves at various times and
calculating the resulting solids concentration in order to depict the interface
settling velocity versus solids concentration as shown in Figure 4§". The design
parameters for the integrated wastewater based on thickening the underflow to a
concentration of 10,000 mg/l are tabulated in Table 21. Based on these data, an
overflow rate of 1,600 gpd/ft2 would be permissible at a design organic loading of
0.5 Ibs BOD5/lb MLVSS/day. However, lower overflow rates should probably be
considered based on past experience relative to scale-up.
ANCILLARY BENCH SCALE STUDIES
Bacterial Quality Characterization
In order to determine the need for disinfection, coliform determinations were made
on the raw industrial wastewaters and on the effluents from the bench scale reactors»
Coliform organisms can result from both fecal and non-fecal sources. Both types of
organisms were investigated. Hereafter, the designation "coliforms" includes all
coliforms whether fecal or non-fecal, and "fecal coliforms" refers only to those
organisms that are primarily the result of fecal contamination.
The DRBC standards require disinfection of any wastewater having an average fecal
coliform concentration in excess of 200 organisms per 100 milliliters. Because of the
low pH and limited contamination of the industrial wastewaters, it is probable that
fecal organisms would be sufficiently destroyed to preclude the need for chlorination
or other means of disinfection.
Municipal sewage was not investigated in this task as coliform counts for individual
sewage effluents are well-documented and such data would have little meaning.
145
-------
Figure 44
ZONE SETTLING CURVES FOR
INDIVIDUAL WASTE WATERS
LOAD w 0.25 LB BOD5/LB MLVSS/DAY
Unit 290, SS=2660mg/l
^ - -
Unit 210, SS=l400mg/l
^—— _
Unit 280, SS= 1340 mg/l
Unit 260, SS = 960 mg/l
Unit 240, SS = l320mg/l
Unit 220, SS=660mg/l
10
20 30 40
TIME (minutes)
50
146
-------
Figure 45
I
o
o
UJ
X
UJ
o:
UJ
ZONE SETTLING CURVES FOR
INDIVIDUAL WASTEWATERS
LOAD » 0.50 LB BOD5/LB MLVSS/DAY
Unit 280, 88* 1440 mg/l
Unit 290,88*2640 mg/l
*x.
Unit 260,88 = 2000 mg/l
Unit 30Q 88 * 3000 mg/l
Unit220, SS = 1010 mg/l
^C13mr240.88 = 1250 mg/l
Unit 230.188* 1160 mo/I
24 36
TIME (minutes)
147
-------
Figure 46
ZONE SETTLING CURVES FOR
INDIVIDUAL WASTEWATERS
LOAD x. 1.0 LB BOD5 /LB MLVSS/DAY
Unit280,SS=l550mg/l
*
IJnit 210, SS= 1400mg/l
Unit 290, SS = 2800mg/l
Unit 30C5T5S « 3700 mg/l
nTT240,SS= 1450 mg/l
Unlt"220,SS = 1250 mg/l
Unit 230, SS= 1000 mg/l
24 36
TIME (minutes)
148
-------
Figure 47
ZONE SETTLING CURVES FOR
INTEGRATED WASTEWATER
Unit 510, SS=2350mg/l,
Load = 1.0
Unit 510, SS*l560mg/l,
Load =0.25
2| Unit 510, SS - 2250mg/l,
Load s 0.50
20 30 40
TIME (minutes)
149
-------
Figure 48
ZONE SETTLING VELOCITY FOR
INTEGRATED WASTEWATER
4000
6000 8000
CONCENTRATION (mg/l)
150
-------
TABLE 21
MIXED LIQUOR THICKENING RESULTS FOR THE INTEGRATED WASTEWATER
Loading
Ibs BOD5
IBs MLVSS/day
-0.25
-0.50
-1.0
Suspended
Assumed
Underflow
mg/l
10,000
10,000
10,000
Solids
Influent
mg/l
1,560
2,250
2,350
Unit Area
sq ft - day/I b
0.16
0.0259
0.173
Overflow
1
Rate
gpd/sq. ft
400
1,600
230
-------
Procedure
Samples of the raw wastewaters and of the effluents from the biological reactors
at loadings of 0.50 and 1.0 Ibs BODj/lb MLVSS/day were tested for the presence
of coliform organisms and fecal coliforms using the Millipore Filter Technique
as described in Standard Methods.
Results
The results of all determinations are summarized in Table 22.
Coliforms were found in only two of the raw wastewaters. Wastewater 021 had
1,300 coliforms per 100 mi Hi liters, but only 30 were of the fecal group. Waste-
water 31 had 10 coliforms per 100 milliliters, but none were of the fecal origin.
All but one of the bench scale reactors had coliforms in their effluents. None
of these, however, were of the fecal group.
Summary
Based on a limited number of samples, fecal organisms in the raw industrial
wastewaters appear to be sufficiently destroyed to not require disinfection.
Coliform organisms do appear in the effluents from the reactors. The organisms
probably were a result of the initial seeding of the reactors, which was done with
an activated sludge treated municipal sewage. It would appear that the coliforms
are now an active part of the bacterial population and would not require disinfect-
ion because they are not of fecal origin.
Chlorination Evaluation
Chlorine demand tests were performed on the effluents from each of the reactors to
determine how much chlorine each of the individual wastewaters would require to
meet the Delaware River Basin Commission's standards for disinfection. These
standards call for a residual of 1.0 mg/l free chlorine after a contact time of
15 minutes. The standards do not mention a combined chlorine residual and,
therefore, these evaluations were limited to free chlorine.
It was determined that the bacterial quality of the individual wastewaters was
such that disinfection probably would not be required. However, depending upon
the degree of contamination from municipal contributors, disinfection could become
necessary and therefore the amount of chlorine required for each stream was
determi ned.
152
-------
TABLE 22
COLIFORM ORGANISMS IN INDUSTRIAL WASTEWATERS
Cn
CO
Industry
Raw Waste
Bio-Reactor Effluents
at Loadings of
0.5 1.0
on
021
031
041
061
071
081
091
101
191
Fecal
#/100 ml
0
30
0
0
0
0
0
0
0
0
Total
#/100ml
0
1300
10
0
0
0
0
0
0
0
Total
#/100 ml
80
1860
180
60
0
100
>2000
20
>2000
Fecal
#/100ml
0
0
0
0
0
0
0
0
0
-------
The orthotolidine flash method was chosen for the determination of free residual
chlorine. Although it is a qualitative technique, it is sufficiently accurate for
the purposes of this task. Other orthotolidine methods were not used because of
potential interferences from nitrite nitrogen and color.
Procedure
1. One hundred milliliter portions of the effluent from each of the reactors at a
loading of approximately 0.5 Ibs BOD5/lb MLVSS/day were placed in beakers
and the color and odor observed.
i
2. The samples were dosed with varying amounts of a standard hypochlorite
solution, agitated, and allowed to stand for 15 minutes.
3. After 15 minutes contact time, the free chlorine residual was determined in
each sample using the orthotolidine flash method as described in Standard Methods.
The effect on color and odor was also observed.
Results
All results are summarized in Table 23. The probable dose of the individual samples
was taken as the average of the sample having a free residual and the sample not
having a free residual.
The sum of the individual requirements is greater than that indicated for the
integrated wastewater. This could be the result of interactions that are taking place
to reduce the chlorine demand of the integrated sample, or it could be the result
of experiment error.
No significant effect on odor or color was observed in any of the samples.
Summary
The results of this task indicate that approximately 25 to 30 Ibs chlorine per MGD
would be required to obtain a free chlorine residual of 1.0 mg/l after a 15 minute
contact time.
Only one wastewater had an abnormally high chlorine demand. However, because of
the low flow of this particular wastewater, it does not have significant effect on the
integrated wastewater.
Because of nitrite and color interferences, the Amperometric Titration Method should
be used to determine chlorine residuals if a high degree of accuracy is required.
154
-------
TABLE 23
CHLORINE DEMAND OF INDUSTRIAL WASTEWATERS
Waste-
water
010
020
030
040
060
080
090
100
Chlorine Dose (a)
Highest
Without
Free Cl
Residual
mg/1
510
60
1
1
5
5
1
10
10
1
Lowest
With
Free Cl
Residual
me/1
70
3
3
10
10
5
15
20
5
Probable
Dose
ma/1
65.0
2.0
2.0
7.5
7.5
3.0
12.5
15.0
3.0
Flow
MGD
0.14
5.4
24.0
38.6
2.4
3.0
1.15
3.0
77.7
Probable
Chlorine
Required,, ,.
Ib/dav W
76
90
400
2,420
150
75
120
380
1,940
Comments
Slight chlorine odor.
Duplicate results at
T = 5°C and T - 20°C.
No significant odor.
Slight chlorine odor.
Slight chlorine odor.
Slight chlorine odor.
No significant odor.
Color interference.
Slight chlorine odor.
Slight chlorine odor.
Slight chlorine odor.
(a) All tests performed at 5°C except as noted.
(b) The sum of industries 10 through 100 equals 3,700 Ib/day.
(c) Integrated wastewater.
155
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Preliminary Activated Carbon Study
Adsorption is a process by which a substance (the adsorbate) is taken up and
becomes attached to the surface of a solid (the adsorbent). The process is
selective in all practical applications, and one component of a mixture may be
adsorbed to a greater extent than another.
Adsorbents have found direct application in waste water treatment for the removal
of organic constituents which are difficult or impossible to remove by conventional
biological treatment processes. The adsorbent which is most commonly applied to
wastewaters is activated carbon.
In this study, effluent from the bench scale reactor treating the composite waste-
water at a loading of approximately 1.0 IDS BOD5/lbs MLVSS/day was treated
with activated carbon to determine the effect on chemical oxygen demand (COD),
biochemical oxygen demand (BOD), methylene blue active substances (MBAS),
phenol, color, and odor. The reactor did not produce sufficient effluent to
operate a continuous carbon column/ and the investigation was therefore limited
to batch studies. Subsequent batch and column studies were performed during the
pilot plant phase of the project and this information is presented in Section VI.
Procedure
1. The activated carbon was soaked for 24 hours in distilled water, then oven-
dried for 24 hours at 103°C.
2. Doses of 41, 68, and 200 mg of the powdered carbon were placed in test
flasks and one liter portions of filtered effluent from the reactor treating the
integrated wastewater were added.
3. Samples were taken every 15 minutes and filtered immediately. This was
continued until the equilibrium concentration was obtained.
4. The COD, BOD, MBAS, phenol, color and odor of the raw and treated samples
were measured.
Data Analysis
The Freundlich isotherm is commonly used to correlate batch adsorption data.
The equation is based on empirical relationships and at equilibrium may be
expressed as:
X/M = kCl/n (V-17)
156
-------
where:
X = the weight of the substance adsorbed
M = the weight of the adsorbent
C = the concentration remaining in solution
k and n = empirical constants depending on temperature, the adsorbent, and the
substance to be adsorbed
Based on this formulation, X/M versus C should plot as a straight line on log paper
thus facilitating both the determination of k and n, and the interpolation of data.
Results
The effect of activated carbon on COD, BOD, MBAS, and phenol are summarized in
Table 24. The Freundlich isotherms for COD, MBAS, and phenol are presented in
Figures 49 through 51, respectively.
The equilibrium concentration was reached in approximately 30 minutes for COD,
BOD, and MBAS. Phenol equilibrium occurred after one hour, with the longer
equilibrium period probably explained by the dilute initial concentration of phenol.
The results indicate that most of the dissolved BOD remaining after biological
treatment can be removed with an activated carbon dose of less than 41 mg/l.
Extrapolation of the MBAS isotherm indicates that a dose of over 500 mg/l
activated carbon would have been required to reduce the MBAS concentration
to the DRBC river objective of 1.0 mg/l. However, interferences attributable to
specific acids in the wastewater render this data questionable, and the results should
be interpreted in this context. Similarly, to reduce the phenol concentration of the
raw wastewater to 0.2 mg/l approximately 430 mg/l activated carbon would be
required.
During testing, significant color reduction was observed at the 200 mg/l activated
carbon dose, with the deep brown initial color diminishing to a very pale yellow.
Indications were that a carbon dose slightly greater than 200 mg/l would remove
most of the color-causative compounds.
The wastewater before activated carbon treatment did not have a noticeable odor
and therefore no effect could be determined.
Summary
The results of the activated carbon batch studies indicate that most of the soluble
BOD remaining after biological treatment was removed with an activated carbon
157
-------
Figure 49
FREUNDLICH ISOTHERM FOR COD
10,000
9,000
ui
o
o
U
o
W
i.
900
100
NOTE:
BIOLOGICALLY TREATED EFFLUENT
USED AS THE WASTEWATER
i I
i
i i
30
40 90 60 TO 8090100
ZOO
3OO 400 9OO6OO 800 1000
C (EQUILIBRIUM CONCENTRATION, mg/l)
158
-------
Figure 50
FREUNDLICH ISOTHERM FOR MB AS
1000
900
o
UJ
ui
a:
V)
CD
oc.
o
a
UI
100
50
NOTE:
BIOLOGICALLY TREATED EFFLUENT
USED AS THE WASTEWATER
10
' ' '
_L
J_
56789 10 20 30409060 708090IOO
C (EQUILIBRIUM CONCENTRATION, mg/l)
159
-------
Figure 51
FREUNDLICH ISOTHERM FOR PHENOL
100
50
o
UJ
I
DC
s
s
I
5
i
10
NOTE:
BIOLOGICALLY TREATED EFFLUENT
USED AS THE WASTEWATER
I i
I
I i
.03 .04 .05 .06.07.00 O.I 0.2 0.3 0.4 0.5 0.60.70.8 1.0
C (EQUILIBRIUM CONCENTRATION, mg/l)
160
-------
TABLE 24
SUMMARY OF RESULTS FOR ACTIVATED CARBON BATCH STUDY
COD BODg MBAS PHENOL
Carbon Dose
mg/l
41
68
200
Concentration
(°) Initial Equil.
rog/I mg/l
235 156
235 145
235 1 16
Percent
Removal
33.6
38.3
50.6
Concentration
Initial Equil.
mg/l mg/l
67
67
67
1.6
1.6
1-.6
Percent
Removal
97.6
97.6
97.6
Concentration
Initial
mg/l
15.7
15.7
15.7
Equil .
rng/l
10.8
8.8
4.3
Percent
Removal
31.2
44.0
72.6
Concentration
Initial
mg/l
1.0
1.0
1.0
Equil.
mg/l
0.24
0.15
0.1
Percent
Removal
76.0
85.0
90.0
(a) Darco Activated Carbon, Grade KB, Manufactured by Atlas Chemical Industries
-------
dose of less than 40 mg/l „ Color removal required a dose slightly in excess
of 200 mg/l. • "
For MBAS and phenol, carbon doses of 500 mg/l and 430 mg/l respectively would
have been required to reduce the concentration of these constituents to the' "
objectives of the DRBC for Zone 5 of the Delaware River. It should be noted,
however, that batch isotherm studies can be considered as "screening tests" only.
They are, however, indicative of carbon capacities, and do establish a basis
for subsequent continuous column studies. A verification of these tests with
additional carbon studies was performed. The results are summarized in Section VI.
FORMULATION OF THE PILOT PLANT EVALUATION PROGRAM ™
The information developed from the bench scale studies and reported in this
Section served two basic functions: (a) an approximation of the degree of
wastewater treatability was established, and (b) the performance and evaluation
program inherent in the operation of the pilot plant could be designed so as to
obtain maximum benefit from the study.
The pilot plant studies, the results of which are cited in Section VI, were
programmed to satisfy many objectives. The more important considerations are
listed as follows:
1) A continuing characterization of all input wastewaters including those organic
and inorganic substances which affect process operation.
2) Monitoring of the neutralization system with respect to chemical demand,
buffering capacity of the combined wastewaters, and operating characteristics
of the process.
3) Analyzing the primary-clarifier with regard to process efficiency as a function
of various operation conditions, nature of the accumulated sludge, and quality
of the primary effluent.
4) Evaluation of the mixed liquor in the aeration basin, including the response of
the microbial population to varying conditions of organic and hydraulic loadings,
temperature, oxygen tension levels, suspended solids concentrations, and other
environmental factors.
5) Determination of the efficiency of secondary clarification at various organic
loadings and hydraulic overflow rates. This includes an evaluation of the sludge
settleability, the degree of thickening which is obtainable and the resulting
recycle rates which are practical, and the nature and concentration of suspended
materials remaining in the effluent overflow.
162
-------
6) Evaluation of the nature and dewaterability of the excess sludge produced
daily within the pilot plant system. This includes primary sludge consisting of
settled suspended materials which were present in the raw wastewaters, chemical
sludge resulting from chemical coagulation and precipitation as well as certain
substances which come out of solution during changes in pH, and excess bio-
logical sludge resulting from microbial synthesis and replication.
7) Application of miscellaneous tertiary or effluent polishing processes within
the treatment system and estimating their application in removing residual and
conservative substances present in the secondary effluent.
8) A detailed characterization of the effluent from the unit processes at each
operating condition. It is necessary to define the processes within the system
in terms of efficiency, operating constraints, and general limitations. The
final effluent must be similarly defined, with the range of resulting effluent
quality being considered in terms of the regulatory criteria.
Operating Factors
The factors of operating variables and ranges, necessary analytical tests for
each system component, operating schedules, and duration of anticipated tests
as conceived at the termination of the bench scale studies are considered herein
and will be discussed individually.
Operating Variables and Ranges
It was necessary to measure the response of the pilot plant system to various
hydraulic and organic loadings, with the intent of translating this information into
basic design criteria for the prototype plant. Based on characterization and the
treatability results reported in this chapter, the following loading conditions were
scheduled to be applied to the biological system.
Operating Condition 1
Organic loading = 0.2 Ibs BODs/lb MLVSS/day
General conditions: BOD5 = 350 mg/l
Detention time = 18 hours
MLVSS = 2300 mg/l
Flow = 18 gpm to individual aeration tank
163
-------
Operating Condition 2
Organic loading = 0.5 Ibs BOD5/lb MLVSS/day
General conditions: BOD^ = 350 mg/I
Detention time = 12 hours
MLVSS = 1400
Flow = 25 gpm to individual aeration tank
Operating Condition 3
Organic loading = 0.8 Ibs BODs/lb MLVSS/day
General conditions: BODg = 350 mg/I
Detention time = 6 hours
MLVSS = 1750 mg/I
Flow = 50 gpm to individual aeration tank
Operating Condition 4
Organic loading = 1.2 Ibs BODs/lb MLVSS/day
General conditions: BOD5 = 350 mg/I
Detention time = 3 hours
MLVSS = 2330
Flow= 50 gpm to individual aeration tank
These loadings were obtained either by operating the three aeration basins in
parallel or in series, depending on the required flow rate and other operational
considerations. The pilot plant is designed to allow parallel operations whereby
each aeration basin can be subjected to the same hydraulic and/or organic load,
while environmental conditions can be varied as required in the individual cells.
Analytical Tests
A tentative test program for the pilot plant program is shown in Figure 52.
Although subsequent modifications were necessary, this tabulation provided a general
testing format which included those analyses deemed necessary to properly evaluate
the pilot program and to formulate the design basis for the full-scale treatment system,
As indicated in this Figure, there are six major testing points within the system train,
each point including those analyses necessary to evaluate the specific unit process or
treatment component. These points will be discussed individually:
1.) Plant Influent - The characteristics of the raw waste were evaluated at the
point where the stored industrial and municipal wastes were blended with the
DuPont Chambers Works waste in the equalization basin. This characterization
164
-------
PROPOSED CONTROL TESTS FOR PILOT PLANT EVALUATION
01
pH
acidity/
alkalinity
SS
VSS
-------
included the necessary organic and inorganic analyses, solids concentrations,
oils, acidity, and specific detection of substances related to potential biological
toxicity and nutrient demand.
2.) Neutralization Effluent -The liquid discharged from the neutralization tanks
was monitored for pH, acidity or alkalinity, and suspended solids.
3.) Reactor-Clarifier Effluent - The primary effluent was analyzed for organic
substances, solids, pH, oils, and other constituents as required, recognizing that
the wastewater at this point represents the actual input to the biological portion of
the system.
4.) Aeration Basin - The mixed liquor in the aeration basin was analyzed to
determine environmental conditions such as pH, temperature, and oxygen tension,
sludge concentration, biological activity, and other tests as required.
5.) Sludge Holding Tank - The accumulated primary, chemical, and excess
activated sludge was pumped to a temporary holding tank, where samples were
withdrawn and characterized according to chemical constituents biological
viability, and dewaterability.
6.) Secondary and/or Tertiary Effluent - The final effluent from the pilot plant
was analyzed in accordance with those tests cited in Figure 52. This included all
analyses necessary to evaluate the efficiency of the total system, to determine
the fate of individual constituents, and to estimate the quality of the treated
effluent with respect to that allowable.
Operating Schedules
The operating schedules for the changing of loading conditions or alteration of
process variables depended primarily on the response of the system to a given
condition, as indicated by the data. Generally, a given load or set of environ-
mental conditions was imposed on the total system or an individual component,
until a "steady state" or a "quasi-steady state" response had been obtained. This
meant that the variation of system responses to a given input, i .e., process
efficiency, oxygen utilization, etc., had been minimized and varied only with
the nominal changes in the raw waste.
Duration of Anticipated Tests
At the outset of the pilot plant tests, a general time table wasoutlined for the
plant operation based on the treatability studies and on past experience. Some
duration from this time frame was imposed, as explained in Section VI.
166
-------
It normally takes three to four weeks for a biological population in an activated
sludge aeration basin to become acclimated to chemical and refinery wastewaters.
Once acclimation is obtained, an additional two to three weeks is required for
the system to become equilibrated to a defined loading level. One or two more
weeks are then required to evaluate properly all of the desired parameters at the
level imposed. If environmental changes occur, additional time is required in
order to allow the biological population to adjust to such changes. Based on the
aforementioned, the estimated duration of each anticipated test was programmed
as shown below:
Time
Condition Description Requirement
System startup - dye studies, etc. 3.0 months
i
Acclimation of biological culture to wastewater 1.0 month
Operating Condition No. 1 (Lowest organic and
hydraulic loading - including equilibration time)
-winter and summer conditions. 1.5 months
Operating Condition No. 2 - Summer and winter conditions 2.0 months
Operating Condition No. 3 - Summer and winter conditions 2.0 months
Operating Condition No. 4 - (highest organic and
hydraulic loading - including equilibration time)
-summer and winter conditions. 2.5 months
General evaluation of various environmental conditions. 1.0 month
General process evaluation; auxiliary studies,
operational and control studies. 6 to 12 months
As previously mentioned and as will be noted in Section VI, several alterations
in process operations and testing procedures were made to fit the situation.
The general format as mentioned here, however, proved applicable in most
instances. Although construction of the pilot plant by Zurn Environmental
Engineers occurred concurrently with the bench scale studies reported herein,
the pilot facility did not come fully operational until the termination of the bench
scale studies.
167
-------
REFERENCES
1. Standard Methods, 12th Ed., American Public Health Association (1965)
2. Eckenfelder, W. W., and Ford, D. L., Water Pollution Control -
Experimental Procedures for Process Design, Pemberton Press,
Austin, (1970).
3. Wallace, A. T., "Anal/sis of Equalization Basins," Journal of the
Sanitary Engineering Division, Proceedings of the American
Society of Civil Engineers, Dec. (1968).
168
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SECTION VI
PILOT PLANT TREATABILITY STUDIES
The development of design criteria and an economic evaluation of the various
wastewater treatment processes can be effected to a limited extent using a bench
scale testing approach as reported in Section V. However, in dealing with complex
industrial-municipal wastewater such as that entering the Deepwater Regional
Treatment System, bench scale studies are constrained because of the very nature
of their operations. Hence, a pilot scale wastewater investigation program was
deemed necessary to evaluate treatment processes under field conditions. Engineer-
ing-Science and Zurn Environmental Engineers designed, constructed, and operated
a 50 gpm biological treatment pilot plant for the purpose of developing these design
criteria. The intent of this Section is to describe the design and subsequent modi-
fications of the pilot plant, discuss its operation and control, outline the data
analysis techniques used in determining design criteria, and evaluate the wastewater
treatment processes tested during the pilot plant program.
PILOT PLANT DESIGN AND MODIFICATIONS
Description of the Pilot Plant Facilities
The pilot plant treatment processes include equalization, neutralization, primary
clarification, aeration, secondary clarification and chlorination as shown in
Figure 53. In addition, other treatment processes have been demonstrated at the
pilot pldnt - including centrifugation, vacuum filtration, filter press dewatering,
carbon adsorption, chemical treatment, aerobic sludge digestion, and effluent
filtration. These ancillary tests were completed utilizing pilot scale equipment
temporarily installed at the pilot plant site.
The "as built" construction drawings for the pilot plant facility are shown in
Figures 54 through 59. Photographs of the pilot plant are shown in Figure 60.
Wastewater Storage
The Deepwater Pilot Plant was designed on a maximum throughput of 50 gpm. Of
the 72,000 gallons of wastewater treated per day, approximately half was trans-
ported to the pilot plant via tank truck, while the remaining wastewater was
pumped Idirectly to the plant from the duPont Chambers Works outfall. Waste-
water storage facilities were provided for the transported wastes utilizing two wood
stave storage tanks, each with a working capacity of 82,150 gallons. Wood
construction was selected because of the corrosive nature of some of the industrial
wastewaters. A 250 gpm truck unloading pump was provided to off-load the 5,600
gallon tank trucks. All necessary piping included within this system was of fiberglass
169
-------
PROCESS FLOW DIAGRAM DEEPWATER PILOT PLANT
SECONDARY
CLARIFICATION
_ ., __ ,__ w^>^ -
9EEES1
WASTEWATER STORAGE
PRIMARY
CLARIFICATION .
TRUCK
Pump
RAW WASTEWATER-UNNEUTRALIZED
RAW WASTEWATER-NEUTRALIZED
AERATION BASIN EFFLUENT
»._•.... RECYCLE SLUDGE
FINAL EFFLUENT
MIXING
Pump
EQUALIZATION
-------
DELAWARE RIVER BASIN COMMISSION
OEEPWATER PILOT PLANT
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DELAWARE RIVER BASIN COMMISSION
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DELAWARE RIVER BASIN COMMISSION
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DELAWARE RIVER BASIN COMMISSION
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Figure 60
PHOTOGRAPHS OF THE DEEPWATER
PILOT PLANT
177
-------
construction, again because of the corrosive nature of some of the wastewaters.
Equalization
The equalization tank provided a blending facility for the transported wastewater
and the waste stream pumped to the pilot plant from the duPont Chambers Works
plant. This tank was also of wood stave construction with a working capacity of
71,000 gallons. A minimum equalization time of 23 hours was achieved when the
tank was completely full and operating at the maximum flow rate of 50 gpm. The
stored wastewater was transferred from the storage tanks to the equalization tank
via a 30 gpm tank transfer pump with the flow controlled by a liquid level control
system on the equalization tank. By the use of this level contrdl system and manual
flow control at the point of the Chambers Works waste stream pick-up, the correct
proportions of the two wastewaters could be obtained .
• v-> '
The original design of the equalization facility provided that the 250 gpm tank
unloading pump also be used for mixing the equalization tank. Because of necessary
trucking schedules, an additional 250 gpm pump was installed in parallel to the
original truck unloading pump in order to allow for continuous mixing of the equali-
zation tank.
Neutralization J
The composite wastewater from the equalization tank was pumped via one of two
20 to 70 gpm process pumps, through a manual flow control and recording system
and into the first stage of a two-stage neutralization system. Each neutralization
tank had a working capacity of 1,200 gallons and was mixed with a three horse-
power agitator. At the maximum flow rate of 50 gpm, the detention time for each
stage was 24 minutes. The neutralization agent applied was high calcium slaked lime.
Control for the neutralization system was implemented by a dual Honeywell pH
controller-recorder with Universal Interloc pH probes and amplifiers. A loop lime
slurry feed system was installed and consisted of two air operated feed valves, two
positive displacement 250 psi feed pumps, and lime slurry storage tanks with agitators.
Back pressure was obtained by installing the first stage reverse-acting air operated
feed valve on the lime recycle effluent line. When lime was needed in the first
stage tank, this valve closed, forcing the lime slurry out the open feed pipe. The
second stage feed valve was installed at the point of entry on the neutralization
tank and required no additional back pressure for operation.
The piping system from the second stage neutralization tank to the primary clarifier
was equipped with a low pH emergency dump system utilizing two air operated valves.
This system was actuated by a low pH signal from the second stage pH probe and was
preset to actuate if the pH dropped below 6.0. This prevented slugs of low pH waste
from entering the biological system if lime feed problems developed. An additional
pH monitoring system was installed in the effluent stream of the primary clarifier as a
final pH check before the waste entered the biological system.
178
-------
Primary Clarification
Primary clarification was provided with a dual purpose Eimco-type reactor clarifier.
This unit acted not only as a conventional clarifier but also could be used for chemical
addition and flocculation as the equipment contained a central mixing turbine and
flocculation well. In addition, sludge thickening space was provided at the bottom
of the structure from which sludge was piped directly to the electrically operated
sludge blowdown valve. Sampling ports were provided above the bottom of the vessel
to allow visual determinations of the sludge blanket height. The necessary frequency
for sludge blowdown could thus be determined.
The clarifier was originally sized for an overflow rate of 1,120 gpd/ft2 at 50 gpm.
However, the geometry of the center reaction well and the effluent weir assembly
was such that the theoretical overflow rate "as built" was 1,529 gpd/ft^ at 50 gpm.
The working volume of the clarifier was 6,150 gallons which allowed a minimum
detention time of two hours at 50 gpm.
Aeration
General - The effluent from the primary clarifier entered a manifold piping
system for the wastewater distribution to the aeration tanks. Three 18,000 gallon
aeration tanks were provided and piped so that they could be operated in parallel,
in series, or independently as required. Each tank was equipped with two header
systems, one for the influent wastewater from the primary clarifier and one for the
return activated sludge from the final clarifiers. Each was configured with; four
feed valves spaced equidistantly along the tank, allowing wastewater and return
sludge to enter the tankage at any desired point. Two of the aeration tanks were
supplied with diffused aeration equipment and the remaining tank was supplied
with mechanical aerators.
Mechanical Aeration Tank - The mechanical aeration tank was equipped with
two Eimco-Simcar 1.5 horsepower surface type aerators. Each aerator had a surface
turbine for aeration and a submerged mixing turbine five feet below the operating
liquid level. The aerators were mounted on adjustable platforms in order that the
submergency of the surface turbines could be varied a maximum of three inches.
This aeration tank was equipped with an effluent weir box to maintain a constant
liquid level at flow rates up to 100 gpm. The tank was also fitted with the!necessary
structural members for the placement of a wood baffle segmenting the tank in half
for a 9,000 gallon aeration chamber. At a 50 gpm wastewater throughput, a
minimum aeration detention time of three hours could be obtained with the baffle
installed.
t
Diffused Aeration - The diffused aeration tanks were equipped with two
air header systems per tank . Each air header, located one foot from the bottom
179
-------
of the tank, had eight Eimco non-clog diffuser plates. An attached Suiterbilt
Rotary Blower with an adjustable speed clutch assembly provided compressed air
at the rate of 200 to 350 cfm at five psi. A Fisher and Porter Flow Tube was
provided to measure the air flow rate from the blower.
The liquid level for both diffused aeration tanks was initially controlled by the four
inch outlet pipes located one foot from the top of each aeration tank. This outlet
piping conveyed the waste to a flow splitter box and then into both final clarifiers.
Subsequent modifications were made to the diffused aeration tanks so that each tank
could be operated independently, utilizing the two final clarifiers separately. Under
this mode of operation, the liquid level was controlled by the height of the overflow
weirs in the final clarifiers.
Secondary Clarification
The effluent from the aeration tanks - as previously mentioned - was conveyed to a
flow splitter box and then into the two final clarifiers. The final clarifiers were
Eimco-type flotation clarifiers and were modified to serve as conventional-type
clarifiers for the biological treatment studies. Each clarifier had a working volume
of 5,000 gallons with a detention time of 3.3 hours and an overflow rate of 380 gpd/
ft* at a 25 gpm throughput. A single sludge return system was initially provided to
serve both clarifiers.
Modifications were made to the clarifiers to provide each of the diffused aeration
tanks with a clarifier and an independent sludge return system. This configuration
allowed testing of two biological systems independently and provided greater
flexibility of pilot plant operations.
Chlor? nation
The effluent from the final clarifiers was piped to a 1,200 gallon chlorine contact
tank. At the maximum flow of 50 gpm, the detention time for this system was 24
minutes. The overflow from this tank was piped to the wood box drainage system
for the pilot plant.
Hydraulic Studies of the Pilot Plant Units
Dye studies were conducted at the Deepwater Pilot Plant to determine the flow
characteristics of the individual units. The purpose of the studies was to insure
that the pilot plant data was evaluated under known hydraulic conditions. Also,
such studies permitted undesirable conditions to be detected and corrected during
the initial phases of the investigation.
180
-------
Procedure
The basic procedure consisted of adding a measured amount of fluorescent dye to the
influent of the particular unit being evaluated and measuring the concentration of dye
in the effluent as a function of time. As discussed below, the flow characteristics in
the unit can be ascertained from the shape of the dye recovery versus time curve.
Two dyes were used successfully during the course of the studies. During the initial
studies, pontacyl brillant pink B was utilized but unfortunately additional supplies
could not be obtained and the final studies were conducted with Rhodamine B-WT.
An attempt was made to use straight Rhodamine B in the aeration tank studies, but
apparently bacterial decay resulted in extremely low dye recoveries and the; use of
that dye was discontinued.
The effluent concentration of dye was measured with a Turner Fluorometer Model
Number 111 equipped with a 546 primary filter and a 590 secondary filter. The
fluorometer was calibrated using serial dilutions of the respective dyes at 20°C.
All samples were brought up to the calibration temperature before determining the
dye concentration.
All of the dye studies were conducted while the pilot plant was treating only the
Chambers Works wastewater. Because fluorescent materials are manufactured at the
plant, there was a slight background concentration of fluorescence that had to be
accounted for in analyzing the data .
Data Analysis
Theoretical Analysis - The main purpose of the flow studies was to determine the
relative amounts of complete mixing, plug flow, and dead space that was occurring
in each unit process and to compare the actual results with the desirable characteristics.
Complex mathematical models have been derived for describing various combinations
of flow regimes that occur in a theoretical hydraulic system. Applications of the
theoretical models to real systems have, in some cases, been quite satisfactory. The
disadvantage of using complex models, however, can be attributed to the fact that the
original purpose of the flow study can be lost in the complexity and accuracy of the
analysis.
The method utilized in this study is based on the flow models proposed in Reference I.
The basic models can be presented graphically as shown in Figures 61 through 63.
Figure 61 shows the effect of dead space on a completely mixed flow system. It can
be shown theoretically that approximately 63 percent of the dye added to a completely
mixed system with no dead space will be recovered after one detent.on time:
181
-------
THEORETICAL DYE RECOVERY CURVES FOR
A COMPLETELY MIXED SYSTEM WITH VARYING
AMOUNTS OF DEAD SPACE
00
N>
D=% DEAD SPACE
O.5
1.0
t/T
1.5
2.0
-------
THEORETICAL DYE RECOVERY CURVES FOR
A COMPLETELY MIXED SYSTEM WITH VARYING
AMOUNTS OF PLUG FLOW
00
CO
P = % PLUG FLOW
2.0
CD
c
3
IS3
-------
THEORETICAL DYE RECOVERY CURVES FOR
A COMPLETELY MIXED SYSTEM WITH VARYING
AMOUNTS OF DEAD SPACE AND PLUG FLOW
00
M = %MIXED FLOW
D = % DEAD SPACE
P * % PLUG FLOW
2.0
-------
Percent Recovery = 100 (1 - e "*/T) = 10Q (1 - e"1 -°) = 63 (Vl-l)
where:
T — detention time
t = actual measured time interval
To determine the amount of dead space in a completely mixed system, it is necessary
only to determine what fraction of a detention time 63 percent of the dye is recovered,
The remaining fraction is then equal to the fraction of dead space in the vessel. As
shown in Rgure 61, if 63 percent of the dye is recovered at tA = 0.75, the amount
of dead space is 0.25 or 25 percent.
Figure 62 shows the effect of plug flow on a completely mixed system. In ihis case,
all of the curves pass through 63 percent dye recovery at t/T = 1.0, but the curves
originate at various points on the abscissa. The fraction of plug flow is equal to the
starting point on the abscissa. For example, a completely mixed system having 50
percent plug flow would have a recovery curve originating at t/T = 0.50, as shown
in Rgure 62.
Figure 63 shows various combinations of plug flow and dead space in a completely
mixed system. The determination of the relative amounts of the three characteristics
proceeds exactly as for the individual cases. For example, a system having 25
percent dead space would show 63 percent dye recovery at t/T = 0.75. If, in the
same system, the remaining volume - i .e., the effective volume - were divided
evenly between completely mixed and plug flow, the curve would originate at
t/T = 0.375 -i.e., one half of (1.0 -0.25).
Interpretation of Field Data - As discussed in the Procedure Section, the
concentration of dye in the effluent from a particular unit was measured versus time.
This was then plotted with concentration as the ordinate and time as the abscissa.
For ease of analysis, both parameters are "normalized" by dividing the concentration
C by C0 and the time t by T where:
C and t = actual concentration of dye after a particular time interval t
£ _ weight of dye added
0 theoretical volume of tank
T = 1.0 detention time = ™lume
flow
The actual percent recovery of dye is then equal to the area under the curve of
C/GO versus tA- A percent recovery versus time curve can be established by
integrating the curve for various time intervals. The latter curve is constructed by
assuming that the area under the concentration versus time curve is equal to 100
percent dye recovery rather than the actual dye recovery.
185
-------
Results
Dye recovery curves for each of the unit processes investigated are presented in
Figures 64 through 76. Two different curves are presented in each figure: the
left ordinate refers to the normalized concentration C/CO/ and the right ordinate
refers to the percent recovery assuming 100 percent dye recovery at t/t = oo .
For both curves, the abscissa is the normalized time interval as t/T.
' s*
Moreover, each figure contains the resulting flow characteristics in terms of the
relative percent of dead space, plug flow, and completely mixed flow. The
resulting flow characteristics are also summarized in Table 25„
/«
jt
Summary ;'
Equalization - The results for the equalization tank indicate that adequate
mixing and circulation are achieved by using a high capacity recycle pump. The
data showed that only 23 percent of the tank was unused or dead space and the
remaining volume had completely mixed characteristics.
Neutralization - The results for both one and two stage neutralization
confirmed that both tanks had completely mixed flow characteristics.
Rea ctor -CI a r i f i e r - The data for the reactor-clarifier were practically identical
with and without the reaction turbine in service. The results indicated that the tank
was approximately 85 percent mixed with T2 percent plug flow and three percent
dead space. Although it would be desirable to have a higher fraction of plug flow,
clarifiers typically perform satisfactorily with 10 to 20 percent plug characteristics.
Normally, a clarifier would have a higher fraction of dead space than indicated by
these results. However, because the entire center section of the vessel is designed
as a completely mixed reactor, the small amount of dead space would be expected.
The limited amount of dead space is quite significant because it indicates that there
is relatively little space available for conventional sludge storage and thickening.
Aeration Tanks - The results for the aeration tanks were essentially identical
for diffused air and mechanical aeration equipment. Both systems had 100 percent
completely mixed characteristics.
Secondary Clarification - The first dye study was conducted on a single
clarifier with an overflow of 25 gpm and an underflow or sludge recycle rate of
25 gpm for a total flow of 50 gpm to the tank. Ideally, under such conditions
50 percent of the dye would be recovered in each stream. Although the data
indicated that the recoveries were 38 and 30 percent respectively for the overflow
and underflow, the most significant result was the complete lack of plug flow for
186
-------
DYE STUDY FOR EQUALIZATION TANK
21 MARCH 1970
C0= 0.246M6/L
Q=45 GPM
T=I435MIN.
100
00
FLOW CHARACTERISTICS
77 % MIXED
23% DEAD SPACE
Background Fluorescence
2.0
-------
DYE STUDY FOR FIRST STAGE NEUTRALIZATION SYSTEM
13 MARCH 1970
C0S 0.536MG/L
Q=50 GPM
T= 24.7 MIN.
FLOW CHARACTERISTICS
100% MIXED
Background Fluorescence
P
0.0
4.O
-------
00
>O
O.O
DYE STUDY FOR TWO-STAGE NEUTRALIZATION SYSTEM
13 MARCH 1970
C0 =0.273 M6/L
= 50 6PM
T= 48.5 MIN.
FLOW CHARACTERISTICS
98% MIXED
2% PLUG
Background Fluorescence
o.o
4.0
-------
DYE STUDY REACTOR CLARIFIER W/TURBINE OFF
16 MARCH 1970
C0= 0.214 M6/L
Q=50 GPM
T= 123.4 MIN
c/c, os
FLOW CHARACTERISTICS
84% MIXED
1 1 % PLUG
5 % DEAD SPACE
Background Fluorescence
o.o
2.0
-------
DYE STUDY R£ACTOR CLARIFIER W/TURBINE ON AT .25 MAX. SPEED
16 MARCH 1970
C0= 0.214 MG/L
Q = 50 GPM
T* 123.4 MIN.
FLOW CHARACTERISTICS
85% MIXED
12% PLUG
3% DEAD SPACE
Background Fluorescence,.
o.o
z.o
-------
DYE STUDY FOR AERATION TANK B
C0 " 0.400 MG/L
27 MARCH 1970
Q = 27 6PM
T = 685 MIN.
1.0
O.9
0.8
0.7
0.6
C/Co
0.5
0.4
0.3
O.Z
O.I
0.0
FLOW CHARACTERISTICS
100% MIXED
o.o
i i i i i i i I i i i i i i i i i I
1.0 2.0
t/T
too
90
8O
70 -o
m
60 I
so a,
m
40 O
n?
JO
30 -<
20
10
-------
DYE STUDY FOR AERATION TANK C
27 MARCH 1970
C0 = 0.400 MG/L
= 23 6PM
T = 800 MIN.
too
•o
CO
FLOW CHARACTERISTICS
100% MIXED
o.
t/T
-------
DYE STUDY FOR SECONDARY CLARIFIER OVERFLOW BEFORE MODIFICATIONS
4 MARCH 1970
CQ= 0.21 M6/L
Q = 25 GPM
T= 202 MIN.
PEAKED AT 2.285
FLOW CHARACTERISTICS
33% MIXED
67% DEAD SPACE
Background Fluorescence
o.o
-------
DYE STUDY FOR SECONDARY CLARIFIER UNDERFLOW BEFORE MODIFICATIONS
4 MARCH 1970
C0 = 0.21 M6/L
GPM
T = 202 MIN.
o
C/C0
FLOW CHARACTERISTICS
30% MIXED
70% DEAD SPACE
Background Fluorescence-^
o.o
0.0
-------
DYE STUDY FOR SECONDARY CLARIFIER OVERFLOW AFTER MODIFICATIONS
9 MARCH 1970
C0=0.2I MG/L
Q=25 GPM
T = 202 MIN.
FLOW CHARACTERISTICS
58% MIXED
7% PLUG
35 % DEAD SPACE
Background Fluorescence
o.o
-------
DYE STUDY FOR SECONDARY CLARIFIER UNDERFLOW AFTER MODIFICATIONS
9 MARCH 1970
C0= 0.21 MG/L
Q =25GPM
T = 202 MIN.
5.0
4.3 H-1 PEAKED AT 6.5
FLOW CHARACTERISTICS
2 % MIXED
98 % DEAD SPACE
i i i i i I
o.o
0.0
O.I
0.9
t/T
-------
>o
00
DYE STUDY FOR SECONDARY CLARIFiER OVERFLOW AFTER MODIFICATIONS
13 MARCH 1970
C0=0.2IMG/L Q = 25GPM T = 202 MIN.
c/c
FLOW CHARACTERISTICS
59% MIXED
12% PLUG
29% DEAD SPACE
Background Fluorescence..
o.o
o.o
0.5
t/T
-------
DYE STUDY FOR SECONDARY CLARIFIER UNDERFLOW AFTER MODIFICATIONS
13 MARCH 1970
C0 =0.21 MG/L
Q = 5 6PM
T = 1010 MIN.
S3
PEAKED AT 2.43
FLOW CHARACTERISTICS
I I % MIXED
89 % DEAD SPACE
Background Fluorescence^
i i i I
i i i i i I
o.o
0.0
0.2
0.3
t/T
-------
TABLE 25
SUMMARY OF DYE STUDY RESULTS AND FLOW CHARACTERISTICS
N>
O
O
Process
Equalization
Neutralization
Neutralization
Reactor-Clarifier
Reactor-Clarifier
Aeration Tank B
Aeration Tank C
Secondary Clarified3)
(a)
Secondary Clarifier
Secondary Clarifier
Secondary Clarifier
Secondary Clarifier
Secondary Clarifier
Figure
IV- 7
IV-8
IV- 9
IV- 10
IV- 11
IV- 12
IV- 13
IV- 14
IV- 15
IV- 16
IV- 17
IV- 18
IV- 19
Conditions
Flow Rate
GPM
45
50
50
50
50
27
23
50 {
f
50 {
30 <
General
Recycle at 350 gpm
One stage
Two stages
Turbine off
Turbine @ 257, speed
Diffused air
Mechanical aeration
Overflow at 25 gpm
Underflow at 25 gpm
Overflow at 25 gpm
Underflow at 25 gpm
Overflow at 25 gpm
Underflow at 5 gpm
Dye
Recovery
Percent-
80-0
101.0
96.0
91.0
63.2
83.5
85-0
38-0
30-0
45-0
54-0
82-0
13-0
Flow
Mixed
Percent
77
100
98
84
85
100
100
33
30
58
2
59
11
Characteristics
Plug
Percent
--
--
2
11
12
--
--
7
--
12
Dead Space
Percent
23
--
--
5
3
--
--
67
70
35
98
29
89
(a) Before modifications to inlet and outlet structures.
-------
the overflow and the fact that the tank had approximately the same amount of
completely mixed space for both the overflow and the underflow.
Normally, a clarifier overflow would have at least a small amount of plug flow
and the underflow would occupy only a very small fraction of the vessel .
Investigation of the tank indicated that the inlet pipe was directed at the effluent
structure, and that the effluent channel did not collect the overflow uniformly
around the tank periphery.
Both secondary clarifiers were modified by installing a deflection plate over the
inlet pipe and cutting more holes in the effluent channel . The dye studies were
then repeated with two sets of conditions: the first with both the overflow and
underflow at 25 gpm; and the second with the overflow at 25 gpm; and the underflow
at five gpm. The results for both cases indicated considerable improvement in the
hydraulic characteristics of the tanks. With the former conditions, the underflow
used an indicated two percent of the volume of the tank and the overflow had seven
percent plug flow characteristics. With the reduced underflow, the amount of plug
flow for the overflow increased to 12 percent and the underflow used an insignificant
12 percent of the total volume of the clarifier.
Determination of Oxygenation Capacity
Although the oxygen transfer efficiency of aeration equipment is furnished by the
manufacturers, this value is subject to many variables such as basin volume, basin
geometry, nature of the waste water, and environmental conditions. The purpose of
this study, therefore, was to obtain general estimate of the oxygenation capacity
of the operating system, using this information as appropriate in designing full scale
facilities.
Procedure
The basic procedure applied in determining the oxygenation capacity of the system
was the insitu approach as described by Kayser (Reference 2). This approach has
the advantages of taking critical measurements with minimum interruption of plant
operation and obtaining data under actual process conditions.
The variation of the oxygen content in an activated sludge system is expressed by
the following equation:
dt
201
-------
where:
°_~ = velocity of changing oxygen concentration (mo/l/hr)
dt
K|_a= overall mass transfer coefficient (hr~')
Csw = oxygen saturation under process conditions (mg/l)
C* = oxygen saturation under equilibrium conditions (mg/l)
C = oxygen concentration in aeration basin (mg/l)
r = microbial respiration rate (mg/l/rir)
If wastewater and recycled sludge inputs to the aeration tank are stopped, the
oxygen uptake rate will become relatively constant following 0.5 to 2 hours of
aeration. When aeration is stopped, the oxygen content in the aeration tank
decreases, the velocity of this decrease being the microbial respiration rate.
If the aeration is started, the oxygen concentration will increase to a certain level
and then remain constant (C*s). Once conditions are stabilized, i.e., dC/dt = 0
and r is constant, then K|_a will be constant and can be evaluated by rearranging
Equation (V1-2):
K|_a = r
C - C*
^sw ^ s
The mass transfer coefficient, K|_a, then must be corrected to a 20°C standard by:
KL°(T) = KLa(20) 1.0241"20 (VI-4)
The oxygenation capacity (O .C .) of the system can then be determined:
O .C. = K|_a(20) (^sw^ (rar|k volume)
The transfer efficiency (T.E.) can then be calculated:
T.E. = OX-
nameplate HP of aerator
Data Analysis
The test was performed using half of aeration basin "C" for the mechanical aerator
evaluation. The wastewater and sludge return flow were stopped, the aerators were
202
-------
turned off following a brief aeration period, and the microbial respiration rate
was determined using a galvanic cell oxygen analyzer. Two verification runs were
made, the data being tabulated in Table 26. The oxygen saturation value of the
wastewater was determined from parallel test tanks at similar environmental
conditions. The oxygenation capacity and transfer efficiency values are calculated
as follows:
Mechanical Aeration -
1. Mass Transfer Coefficient Determination
Qw = 7.48 mg/l (observed)
C*s = 3.60 mg/l (observed)
T = 29°C
r avg.= 30 mg 02/l/hr
K,a= E = 3° = 7.74 hr'1
CSW-C*S 3.88
7.74=KLa(20) 1.02429"20
KLa(20)» 7'74 = 6 .25 hr"1
V ; 1.238
2. Oxygenation Capacity Determination (20°C)
O.C.= 6'25 7.48 mg/l o.mnjr.1. 8.34 Ibs
hr 106 gal. mg/l
O.C. = 3.50 Ibs 02/hr
3. Transfer Efficiency Determination (20°C)
I.E. = 3.50 Ibs OVhr * 2.90 Ibs 02/HP-hr
1.5 HP -0.3 HP (turbine)
203
-------
TABLE 26
OXYGENATION CAPACITY DETERMINATION
Conditions: Nameplate H.P. - 1.5 (Mechanical Aeration)
Liquid Volume - 9,000 gal.
Temperature - 84°F = 29°C
Time
(min.)
Run No . 1
OiOO
0:30
1:00
1:30
2:00
3:00
5:00
Run No. 2
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
Analyze*
Reading
1.6
1.9
2.8
3.3
3.4
3.5
3.6
Avg. 02 Uptake Rate,
1.6
2.0
2.6
3.0
3.4
3.5
3.6
3.6
Dissolved Oxygen
(mg/l)
1.45
1.72
2,54
3.00
3.10
3.18
3.28
r, = 33 mg/I/1ir
1.45
1.82
2.46
2.73
3.04
3.19
3.38
3.28
Avg. 02 Uptake Rate, r, = 28 mg/l/hr
204
-------
Diffused Aeration -
1. Mass Transfer Coefficient Determination
Csw =7.88 mg/l (observed)
C s = 6.55 mg/l (observed)
T =29°C
r avg. = 8 mg 02/1 /4ir
KLa= 1 = § = d.Ohr"1
Csw - C*s 1.33
6.00 = KLa(20) 1.024 29~20
Kla(20) = 6'°° =4.85 hr'1
1.238
2. Oxygenation Capacity Determination (20°C)
O'C =( 4-85 V7-88 mg/iyi8,000 gal .V 8.34
\ hr )\ A A 106 gal.
O.C.=5.74lbs02/hr
3. Transfer Efficiency Determination (2QoC)
T. E. = 5.74 Ibs02/hr= 1.15 Ibs 02/HP-hr
5 HP
Summary
The oxygen transfer efficiencies of the aeration systems at the pilot plant have been
evaluated. The values agree quite closely with observations previously reported
for similar conditions. For example, the surface aerator transfer efficiency of
2.90 Ibs 02/HP hr at a power level of 1.5/9000 = 0.17 HP/1000 gal. agrees with
the relationship shown in Figure 77. (Reference 3).
CONTROL AND OPERATION OF THE PILOT PLANT
The control and operation of the pilot plant involved many of the activities that
would be encountered in a prototype system. To augment the operational control
and maintenance of the pilot plant, operators were contracted through the duPont
Company on a full-time basis with one operator per shift, three shifts per day.
Ibs
mg/l
205
-------
Figure 77
SURFACE AERATOR CHARACTERISTICS
cc
»
a.
c?
CO
0.2 0.3 0.4
HP/1000 GAL
206
-------
seven days per week. In addition, qualified laboratory technicians and the
necessary analytical equipment were provided under this contract. Engineering-
Science, Inc. directly supervised the operators and laboratory personnel resident
at the plant site. Described herein is the wastewater collection and sampling
system, and the pilot plant instrumentation and hydraulic controls that were utilized
during the pilot plant study.
Wastewater Col lection and Sampling Program ,
Transported Wastewater
** ''""-** '•> ' * * * * ,
The composition schedule for the integrated wastewater treated at the pilot plant
was based on 1975 projected flow estimates as shown in Table 27* Based on these
original flow estimates, approximately 44 percent of the wastewater was contributed
by the participants outside of the duPont Chambers Works. This wastewater,
212,000 gallons per week as tabulated in Table 28, was transported to the pilot
plant facility via tank truck on a five day per week basis. The trucking schedule
is shown in Table 29. This schedule allowed for maximum utilization of the
transport equipment while also satisfying the various truck loading requirements of
the individual participants. Moreover, the schedule was arranged so that the
compositing of the integrated wastewater was as close to field conditions as physically
possible. The storage tanks at the pilot plant were operated in parallel on a
continuous withdrawal basis. Each Monday the stored wastewater inventory was
82,000 gallons while on each Friday the stored wastewater inventory was a
maximum of 164,000 gallons. This arrangement allowed for the continuous operation
of the plant on a seven day per week basis using the integrated wastewater as a
feed source.
The pilot plant studies were initiated on April 1, 1970. At that time, the B. F.
Goodrich plant was still under construction and therefore no wastewater was
transported from this participant until the Fall of 1970. The wastewater from
Houdry Chemical Company was also omitted because of the small flow and because
the analyses made during the bench scale studies indicated that most of the waste-
water was uncontaminoted once-through cooling water. As further revised flow
estimates were made by the various participants, it became necessary to make
adjustments to the. wastewater compositing schedule. Tabjles 30 through 32 present
these revised flow estimates and the revised trucking schedule for the "winter loading"
conditions at the pilot plant.
the truck loading facilities at each of the various participant locations were the
sdme sampling points utilized during the bench scale wasjewater characterization
studies. The transport trailers were equipped with 400 gpm gasoline-powered,
self-priming centrifugal pumps for self loading. Each loading facility was fitted
207
-------
TABLE 27
INDIVIDUAL PARTICIPANT CONTRIBUTIONS FOR THE INTEGRATED PILOT
PLANT WASTEWATER SUMMER LOADINGS
N>
Participant
duPont Chambers
Works
Texaco
Shell
Mobil
Hercules
duPont Repauno
Monsanto
B.F. Goodrich**
glu Pont Carney's
Municipalities
Estimated 1975
Flow(MGD)*
45.21
5.40
3.00
14.00
0.14
0.29
3.00
1.20
Point 2.40
6.00
Percent of
Total
56.06
6.70
3.70
17.36
0.17
0.36
3.72
1.49
2.98
7.44
Gal . Needed
Per Day
40,363
4,824
2,678
12,992
122
259
2,678
1,073
2,146
5,357
Gal . Needed
Per Week
282,542
33,768
18,749
87,749
856
1,814
18,748
7,509
15,019
37,497
Number of 5600 Gal .
Tank Truck Loads/Wk
(Pumped to Pilot Plant)
6
3
16
856 Gal .
1,814 Gal.
3
3
7
TOTAL
80.64
100.00%
72,492
503,996
* Estimates were effective as of May 1970
**Plant was not in operation during the summer
-------
TABLE 28
PARTICIPANT WASTEWATER CONTRIBUTIONS BASED ON TRUCKING SCHEDULE*
to
Participant
duPont Chambers Works
Texaco
Shell
Mobil
Hercules
duPont Repauno
Monsanto
duPont Carney's Point
Municipalities
TOTAL
Number of Truck
Loads Per Week
(5600 Gal . ea .)
(Pumped to
Pilot Plant)
6
3
12
-
-
3
3
7
Partial Loads
Per Week Total Gallons
(gal.)' Per Week
292,000
33,600
16,800
19,000 86,200
750 750
1,900 1,900
16,800
16,800
39,200
504,050
Percent of
Total
as Trucked
57.94
6.67
3.33
17.10
0.15
0.37
3.33
3.33
7.78
100.00%
*For summer loading
-------
TABLE 29
DEEPWATER PILOT PLANT TRUCKING SCHEDULE FOR SUMMER LOADINGS
Number One Truck
Monday
Mobil
Texaco
Monsanto
Municipalities
Tuesday
Wednesday
Mobil Mobil
Mobil Mobil
f Mobil-4650 go I. Monsanto
\Repauno-950 gal. Municipalities
Municipalities Municipalities
Thursday
Mobil
Mobil
Municipalities
Municipalities
Friday
Texaco
f Mobil -4650 gal.
\Repauno - 950 gal.
Monsanto
Municipalities
jo
o
Number Two Truck
Shell
Carney's Point
Mobil
Mobil
f Mobil -5225gal.
\Hercules - 375 gal
Texaco
Mobil
Texaco
Shell
Carney's Point
Texaco
Texaco
Mobil
/Mobil -5226gal.
[Hercules - 375 gal
Carney's Point
She! I
Mobil
Capacity for each truck = 5600 gal
-------
TABLE 30
INDIVIDUAL PARTICIPANT CONTRIBUTIONS FOR INTEGRATED PILOT PLANT
WASTEWATER WINTER LOADINGS
Revised 1975
>articipant Flow (MGD)*
duPont Chambers
Works
Texaco
Shell
Mobil
Hercules
duPont Repauno
Monsanto
B.F. Goodrich
duPont Carney's
Point
Houdry**
Municipalities
45.21
6.80
3.00
14.00
0.16
0.25
3.25
1.30
3.18
0.25
5.57
Percent of
Total
54.50
8.20
3.61
16.87
0.20
0.30
3.92
1.57
3.83
0.30
6.70
Gal . Needed
Per Day
39,240
5,904
2,599
12,146
144
216
2,822
1,130
2,758
216
4,824
Gal . Needed Number of 5600 Gal .
Per Week Tank Truck Loads/Wk .
274,680
41,328
18,194
85,024
1,008
1,512
19,757
7,912
19,303
1,512
33,768
(Pumped to Pilot Plant)
7
3
15
1,008 Gal.
1,512 Gal.
3
7,912001.
3
-_
6
TOTAL
82.97 MGD 100.00%
71,990
* Estimates were effective as of August 1970
** Waste not trucked to Pilot Plant
503,998
-------
TABLE 31
PART 1CIPANT WASTEWATER CONTRIBUTIONS BASED ON REVISED TRUCKING SCHEDULE*
Participant
duPont Chambers
Works
Texaco
Shell
Mobil
Hercules
duPont Repauno
Monsanto
B. F. Goodrich
duPont Carney's
Point
Municipalities
Number of Truck Partial Loads
Loads Per Week Per Week
(5600 Gal . ea .) (gal.)
7
3
11 19,900
1,000
1,500
3
8,000
3
6
Total Gallons
Per Week
288,800
39,200
16,800
81,500
1,000
1,500
16,800
8,000
16,800
33,600
Percent of
Total
57.30
7.78
3.33
16.17
0.20
0.30
3.33
1.59
3.33
6.67
TOTAL
504,000
100.00
* For winter loadings
-------
TABLE 32
DEEPWATER PILOT PLANT TRUCKING SCHEDULE FOR WINTER LOADINGS
Number One Truck
Monday
Mobil
Texaco
Monsanto
Municipalities
ro
CO
Number Two Truck
Shell
Carney's Point
Mobil
Mobil
Tuesday Wednesday
Mobil Mobil
B.F. Goodrich- Mobil
4,000 gal.
Monsanto
/Mobil - 4850 gal . Municipalities
[Repauno -750 gal . Municipalities
Municipalities
1 Mobi 1 - 5 1 00 gal . Texaco
*• Hercules - 500 gal . Texaco
Texaco Shell
Mobil Carney's Point
Thursday
Mobil
Mobil
Municipalities
Municipalities
Texaco
Texaco
Mobil
Friday
Texaco
B.F. Goodrich-
4,000 gal.
JMobil -4850 gal.
{Repauno - 750 gal .
Monsanto
fMobil -5100 gal.
I Hercules - 500 gal .
Carney's Point
Shell
Mobil
Capacity for each truck = 5600 gal.
-------
with three inch pipe connections and located to allow access to trucking equipment.
In some cases, arrangements were made to fill the tank trucks by in-house pumping
facilities. All the truck loads represented grab type samples with the exception of
the duPont Repauno and the Hercules samples. These two plants had equalization
and/or large volume compositing facilities in-house.
Chambers Works Wastewater Collection System
The wastewater conveyance system at the Chambers Works consisted of two streams-
namely, the organic waste stream and the cooling water waste stream. The organic
waste stream was utilized for the pilot plant make-up. This wastewater was pumped
directly to the pilot plant on a continuous basis through a flow metering and
control system. A composite sampling system as described later in this Section
was used to collect 24-hour composite samples. <
Modifications were later made to this collection system because of necessary
construction carried out by the duPont Company at the location of the pump intake.
A 1,500 gallon head tank was installed and became the intake facility for the
wastewater pump. The organic waste stream was then transferred via two additional
pumps to the head tank from the two streams that made up the total organic waste
stream flow.
Pilot Plant Sampling System
In order to obtain selected composite samples for the evaluation of unit processes,
an automatic sampling system was installed at the pilot plant. Since the flow
through the plant was constant, grab type samples taken on a regular sequence and
composited over identical time periods represented true composites proportional to
flow. The system itself, as shown in Figure 78, consisted of six Protec Model
sampling foot valves connected in parallel with an electrically controlled air supply
system. The foot valves were submerged in the integrated wastewater sampling
bucket, the Chambers Works sampling bucket, the second stage neutralization tank,
the effluent weir box of the primary clarifier, and the effluent weir boxes of the
two final clarifiers. The force of the water filled the 20 milliliter sample chamber
via a ball check valve. When the timing clocks actuated the three-way solenoid
valve, air pressure was applied to the sampling chambers forcing the sample out
the effluent pipe of the samplers and to compositing carboys in a refrigerator
at 4 °C. The cycle time for each grab sample was set for 15 minute intervals
with 25 seconds of air pressure applied per interval. Using this system, a sample
of approximately two liters per 24 hours was collected at each sample point.
Once every 24-hour period, the carboys were transported to the laboratory for
analysis.
214
-------
N>
AIR OPERATED AUTOMATIC SAMPLING SYSTEM FOR PILOT PLANT
SUBMERGED FOOT
VALVES
BY PROTEC INC.
SAMPLE BUCKET
3/6 " AIR SUPPLY LINE
CHAMBERS WORKS WASTE -
SECOND STAGE NEUTRALIZATION
3 WAY SOLENOID
VALVE
AIR PRESSURE REGULATOR^
DUAL TIME
. CLOCKS
EXHAUST
EFFLUENT PRIMARY CLARIFIER
EFTLUENT SECONDARY CLARIFIER
SAMPLE RETURN7
LINES (1/4"plostic '
tubinq)
REFRIGERATOR
AT 4JC
~n
5"
i
oo
-------
In addition to the composited samples, grab samples were taken once per 24-hour
period of the mixed liquor and sludge blowdowns. As these particular samples are
time-de pendent, composites could not be made. The samples from each tank truck
load were also grab type samples.
Instrumentation and Hydraulic Control of the Pilot Plant
Instrumentation of the Pilot Plant
The pilot plant was equipped with only minimal control instrumentation as complete
laboratory facilities were available at the Chambers Works, alleviating the need
for sophisticated instrumentation at the plant site. The control'instrumentation
consisted of a dual Honeywell pH recorder-controller with Universal Interloc pH
probes installed in both stages of the two stage neutralization system. Recording
instrumentation consisted of Honeywell temperature and dissolved oxygen equipment
that was installed in the aeration tankage. In addition, portable pH and dissolved
oxygen instruments were kept on hand at the pilot plant to spot check and calibrate
the recording instrument.
Hydraulic Control System
The hydraulic control of the pilot plant was augmented by the use of two Hammel
Dahl Flow Tubes with Honeywell recorders located on the total process flow and
the Chambers Works waste streams. Manually-operated diaphragm valves were placed
downstream from the flow tubes and provided adequate flow controlling schemes.
In addition, Sparling propeller-type flow indicator/totalizers were installed on the
feed system to the aeration tanks and the sludge return system as noted in Figure 77.
Each sludge return meter was downstream from in-line screens to avoid meter plugging.
DATA COLLECTION AND ELECTRONIC DATA ANALYSIS
The voluminous quantity of information that was generated in the course of this study
necessitated the use of computer techniques for data processing. The development
of the design parameters and coefficients for biological waste treatment processes
involves numerous mathematical calculations which are both time-consuming and
subject to computational error. In addition, it is valuable for the user of these data
to know the statistical reliability of his information. In recognition of these limita-
tions, two computer programs were written. The first program summarized and
printed out the daily pilot plant data, and the second program developed the design
parameters from this information. The acronym "STATPK" was assigned to the latter
program. The following discussion will include a description of each of these
programs.
216
-------
Data Collection and Management Procedures
An analytical program was established around each of the unit processes at the
pilot plant and designed for maximum data retrieval and utilization. Since
computer techniques were used to summarize and tabulate the data, it was con-
venient to identify each sample by an eleven digit number as follows:
*** ** ** ** *#
LOCATION YEAR MONTH DAY HOUR
The location number of the individual samples are outlined in Table 33. The hour
code was based on the 24-hour system and designated either the time of grab
sampling or the end of the compositing period .
Samples were transported to the laboratory each morning and the analytical
schedule presented in Table 34 was followed. Results of analytical tests such as
oxygen uptake, solids and COD were sent back to the pilot plant during the
afternoon of the sampling day. This procedure provided direct operational control
of the pilot plant based on these laboratory results.
Data Summary Computer Program
The basic procedure for handling the raw laboratory data included its tabulation
on standardized data sheets, transferring it to computer cards, and processing it
using a FORTRAN program. This basic procedure was used successfully to handle
the data from the wastewater characterization and bench scale rreatability studies.
The Fortran program as described in Section V was modified to read out the pilot
plant responses to various wastewater inputs. The output sheets from this program
summarized the data from each of the unit processes and presented all necessary
parameters of the operation unit. Additionally, the total pilot plant performance
was presented in terms of removal efficiencies across the plant. This program
was run at the end of each calendar month and printouts were presented as monthly
task reports.
STATPK Program
The availability and utility of high-speed electronic computers gives the environ-
mental engineer a tool which he can use to relieve himself of tedious and complicated
mathematical procedures. In view of the myriad of data accumulated during the
bench and pilot scale phases of this project, a computer program was developed to
perform the necessary mathematical operations on biological waste treatment process
information and to arrive at the required design information and the errors associated
with it. The resolution of the pilot plant data is subsequently presented in this
Section. A description of the STATPK program is presented in Appendix A.
217
-------
TABLE 33
IDENTIFICATION AND LOCATION OF SAMPLE POINT NUMBERS
Description Number
Plant Inlet - Raw Wastewater 601
Neutralization Process 610
Effluent from Second Stage Neutralization 610
Chemical Feed to Neutralization 613
Primary Clarification Process 620
Effluent from Primary Clarification 621
Chemical Feed to Primary Clarifier 622
Sludge from Primary Clarifier 623
Activated Sludge Process 630
Mixed Liquor from Aeration Tank A 631
Mixed Liquor from Aeration Tank B 632
Mixed Liquor from Aeration Tank C 633
Filtered Effluent from Activated Sludge Process 634
Settled Effluent from Activated Sludge Process 636
Waste Sludge from Activated Sludge Process 637
Return Sludge to Activated Sludge Process 638
Final Effluent from Pilot Plant 699
218
-------
TABLE 34
DAILY ANALYTICAL SCHEDULE FOR PILOT PLANT
Truck
601 610 621 623 631 632 633 634 636 637 638 699 Samples
Alkalinity
Acidity
Neut.w/acid to 7
Neut.w/bdse to 7
TDS x x
YDS x x
TSS xxx xxxx xxx
VSS xxx xxxx xxx
COD unfiltered x x x x
I COD filtered x x xxxx
BOD5 unfiltered x x x
BO05 filtered x x x
TOC unfiltered x x x
TOC unfiltered x
TOD unfiltered x x x x
TOD filtered x x
pH xxxxxxx x
Elec. Cond.
Kjeldahl N. x x
Ammonia N. x x
NO2 + NO3 x x
Total P x x
Phenol x x
MBAS x x
Color xx x
Grease and Oil x x
Heavy Metals x x x x
Volume F F F
Flow F F
Lime added (ft.) F
Lime Sol. (*/ga\.) F
Temp. («>F) x xxx x
02 Uptake xxx
SVI xxx
219
-------
PILOT PLANT PROCESS EVALUATION - BIOLOGICAL TREATMENT
The pilot plant process evaluation with respect to the biological removal of organics
was conducted in a manner similar to that previously described for the bench scale
portion of Section V. The basic approach involved the application of various
organic loadings to the activated sludge system while monitoring the resultant
responses in terms of sludge build-up/ organic removal efficiency, and oxygen
utilization. In order to further delineate this evaluation, the organic loading
levels were applied under both summer and winter conditions. Therefore, the
hydraulic and organic loadings could be controlled with some semblance of
temperature regulation.
The intent of this section is to describe the operating schedule followed during
this process evaluation, present the summarized results of the data gathered during
these tests, define the design parameters and coefficients as developed from a
statistical analysis of the data, and discuss the effects of temperature and transient
loading on the biological system. As the abundance of data generated during the
pilot plant studies prevents its total inclusion in this text, only pertinent data are
presented. The daily operational data has been presented under separate cover as
monthly task reports.
Operating Schedule
The pilot plant operating schedule as originally envisioned is schematically out-
lined in Figure 79. This schedule was generally implemented throughout the
pilot studies with the following exceptions:
(a) the proposed organic loadings of 0.75 and 1.2 Ibs BOD5/lb MLVSS/day were
never obtained in September and October of 1970 as the cooling water usage of the
various participants resulted in a lower than anticipated BOD concentration in the
untreated wastewater; and,
(b) the initiation of the winter loading studies was delayed by a trucking strike
which occurred in November of 1970.
These two combined factors forced a scheduling change which substituted the transient
loading study for the high organic loading study. Moreover, extremely cold weather
resulted in a two week shutdown of the pilot plant during February of .1971. Ancillary
process evaluation studies such as carbon adsorption, sludge handling, and filtration
were expanded to include necessary design and treatment process evaluation.
Results of the Summer and Winter Loading Conditions
General
The pilot scale biological treatment data covering the activated sludge studies are
220
-------
PILOT STUDIES OPERATION SCHEDULE
1970
Apri1 Hay June lu1y Aug,
TASK P-7, 11
Pilot Plant
Biological
Studies
— 50 JOT,
Org. Load
- 0 15-
0.24
Org. Loa
= 0.45-
0.55
• 0.75-
O.Bi
Organic Loading in His SOD/day' lh MI.VSS
• WARM WEATHER CONDITIONS •
COI.U KKATHKK t:uNI)lTtO"S
Cht
1-Aerat ion
Tank
TASK P-ll
TASK P-b. 11
TASK P-9. 10
Submittal of Refine
Treat (sent Facil ity
Cost Estimate
d
Rcpor
TASK P-lt
l)ix«S i'»"
Studi s
l-Atr -
ri.iti ank
J
Operal ion-Spot fal S Indies
as Kvqn i rod
t'ri-|.arat i.ni of Fittal Ktf>»rt
CO
c
-------
presented graphically in Figures 80 through 83. Figure 80 presents the organic
loadings in terms of COD and BOD5 while Figures 81 and 82 present the COD and
BOD5 concentrations of the untreated wastewater (601), the primary clarifier
effluent (621), and the final effluent (636). Figure 83 presents the mixed liquor
solids (MLSS) concentrations and temperature. Additionally, operational modes are
noted on each of the Figures in conjunction with explanations of process difficulties.
At the outset, several general conclusions can be established from the pilot plant data.
First, there is a distinct seasonal variation in the organic concentration of the
combined wastewater. This variation is underscored by the difference in the COD
and BOD5 values of the raw wastewater during May and June of 1970. The
average BOD5 of the raw wastewater during May was approximately 350 mg/l,
while during the last of June the average BOD5 was approximately 200 mg/l.
Low BODs and COD values were experienced throughout the warm summer months.
This significant variation is the result of additional usage of once-through cooling
water during the summer months, acting as a diluent to the raw wastewater. As
economic considerations dictate the in-plant segregation of cooling and process
waste waters, it is expected that this seasonal variation of the organic characteristics
in the regional system will be less pronounced than experienced at the pilot plant.
In addition to the seasonal variations, daily organic variations were also experienced „
The changing nature of the wastewaters which were both trucked from the participating
industries as well as pumped directly from the Chambers Works plant resulted in a
restricted form of transient loading to the aeration basin. Based on participant
equalization requirements and the equalization of flows in the interceptor, it is
anticipated that the degree of fluctuation in organic loading will not be any more
severe in the full scale system than observed in the pilot plant studies. However,
as a precautionary measure, more pronounced fluctuations were deliberately im-
posed on the pilot plant system using the Chambers Works wastewater. The results
are subsequently discussed in this section, although no marked deterioration of the
biological system was noted during this test series,
Several minor biological upsets were observed during the pilot plant studies as a
result of sulfide dumps, short-lived pH variations, and nitro-benzene dumps.
Although the removal efficiencies were reduced during these upsets, a complete
biological kill was never experienced during the entire pilot plant operation.
This notwithstanding, a biological system is subject to occasional physical,
chemical, biochemical, or environmental stresses which temporarily reduce the
overall system efficiency. Proper design features, however, can minimize
biological upsets.
Biological Treatment Removal Efficiencies
The observed removal efficiencies in terms of BODs and COD generally decrease
222
-------
PILOT PLANT ORGANIC LOADINGS AND OXYGEN UPTAKE
5
EL
N>
CO
C/}
O
Z
I
in
Q
O
CD
O
O
O
A Hr AERATION DETENTION TtME
le.OOCtai AERATION VOLUME
I AERAfiON TANK
90 IE"" FLOW
COMBINED WASTEWATER FEED
24 Hi COMHtNEO rLOMT
3 hi AERATION OCTENTION T
9.000 «B1 AERATION VOLUME
I AERATION TANK
30 «p« *L01»
COMBINED MAITEMATEN flED
14 «' COM0IMCO *
EOUALIZAT)ON
29 gvm 'LOU
C« MwaTCHMTEN ONL*
NO EOUM.IZjmOM
t AERATION TANK
COMBINED1" WAST € WATER
FEED
14 til COMBINED FLO*
EQUALIZATION
SEPTEMBER 1970
CO
c
00
o
-------
PILOT PLANT ORGANIC LOADINGS AND OXYGEN UPTAKE
I
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to
1
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100
80
60
4O
20
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PILOT PLANT EFFICIENCY - COD REMOVAL
14.4'J', |«' AERATION *OIUWt
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COMB'MCO M&M«*TEf> Flit
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MAY I 970
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1 ". AE»*'IOH «-£"*' 01 ' Ht
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AUGUST 1970
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- • AC RAT t CM TAKK —
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I
SEPTEMBER 1970
ss
u
i
T 1 T
OCTOBER
-------
PILOT PLANT EFFICIENCY - COD REMOVAL
100
80
6O
40
20
0
KJ
O
o
inANi.it MI i DADiNU sruDr
fi hi A[RA!iON (IMtNliON TlMI
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IB.OOOgDl AfHAIIO
-i Af RATION 1ANK
tO gprn PLOW
rw WASTE WATER >>
MO t OIIAI IfANON
1970
TRANSIiNT I OHO IMC STUDV
7 hr AERATION DETENTION "ME
8.000 gal AERATION VOLUME
AE3A1ION TANK
AERATION TANK
9pm FIQW
BINED
CW - NO EQUAUZATION
COLO WEATHER
- OPERATIONAL -
SHUTDOWN
UJ^j
NOVEMBER 1970
DECEMBER 1970
JANUARY 1971
300 gal '
VOLUME
TANK
to gem FLOW
•OMBINEO WASTEWATER
FEED
:w - NO EQUALIZATION
>4 Br TRANSPORTED
WASTEWATER »
EQUALIZATION G
I PARALLEL SYSTEMS
6 hi AND .12 hr AERATION OETeNTION
TIMES
FEBRUARY 1971
O, D 6 tu AERATION DETENTION TiME
*.• I£M AERATION DETENT ON T>ME
MARCH 1971
o
(D CO
Q- —i
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100
80
60
40 -
20
TOO
600
_ SOO
|" 4OO
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ZOO
100
0
o
m
PILOT PLANT EFFICIENCY - BOD5 REMOVAL
IBM AEHATlDN DETENTION TtMt
94,400 f«l MMTlON VOkUME
„ 9 ACKATlON TANK! IN Mft*.l.LlL .
to um FLO»
COIMiNIO VA>TE
MO tOU«LIZAflOM
SEPTEMBER 1970
OCTOBER
CO
f
00
-------
PILOT PLANT EFFICIENCY - BOD5 REMOVAL
KJ
~ (D
-------
PILOT PLANT MIXED LIQUOR CONDITIONS
cc
IU
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100
80
60
40
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3,200
2,800
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> AERATION TANK* IN PARALLEL ,
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14 hi COMBINED H.OW EQUALIZATION
il a! a^
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1 «
MAY 1970
12 hi AERATION DETENTION TIIIE
H.*OOI«I AERATION VOLUME
t AERATION TANKS IN PARALLEL.
CoJSmtO MASTCWATER FEED
Z4 ft. COMBINED FLOW
EQUALIZATION
il
TSS
vss
JUNE I97O
Kf AEMTiQN DETENTION TiW
t.OOOjal AERATION VOLUME
I AERATION TANK
f LOW " '
D WASTEWATCR f£EO
Z4 h> COMBINED FLOW
EQUAL HAT ION
•1 •!
$ Is
!i al
JULY 1970
6 hr AERATfON
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l«.000 ggl AERATION
\— VOLUME -
I AERATION TA«M
JO BOH, FLOW
COMBINED WAsTEftATE
J l» AEMATiON DETENTION TIME
9,000 gal AEOATION VOLUME
h/Z AEHATIQH TAHK
AUGUST 1970
mAHSItWT
in/ AE**I
.ITIQN TANI
iflpn FLOW
WASTEWATEH ON
> EQUALIZATION
\
_1_
_l_
_1_
_1_
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SEPTEMBER 1970
OCTOBER
c'
i
oo
CO
-------
PILOT PLANT MIXED LIQUOR CONDITIONS
ro
jtx 1CII>tIOW DCTIN1-O* t'ttt
19-OOOt*' *E*ktiON VKU»M
j »f»»Tt T*ANSPO*TEO *AS'(**TE« COUALIZATIOM
NOVEMBER 197O
TSS
VSS-
DECEMBER "970"
_ _
to is
JANUARY 1971
« Hf AEIUTlOM OCTCttTlG
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—— VOLtMK —
I KffftTlOM TANK
50 tfm fiQm
COHtlMCO W«STC«r*TCH
rifti
C* - MO EQUALIIATI
?4 IIP T«AMS.«CmTED
»*STE»ATEB
EQUAL lZ«TiO
«HO tlkr ACH'TIDM KTEMT1OM
VOLUMES
23 »• FLOW TMtv (MM SV9TCM
COAINCO HSTEwmil FCEO
I* M COHBITIEO FLO* EOWLIlaTIO
-------
with a decrease m aeration detention time as shown in Figures 81 and 82. Moreover,
the removal efficiencies dropped markedly during the winter loading series due to
the cold weather effects on the biological system. Recognizing that as the organic
loading increases, the removal efficiency decreases, data groups having an
approximate BODs loading of 0.2 Ibs BOD5/lb MLVSS/day were selected at each
of the four detention periods tested during the summer months. Figure 84 presents
this summarized data and reflects the removal efficiencies across the total pilot
plant system. As noted, the removal efficiency was the highest at the twelve
hour detention time and decreased as the detention time was decreased and the,
organic load was increased. The organic removal efficiencies across the aeration
basin alone decrease even more dramatically as shown in Figure 85.
The removal efficiencies observed during the winter months were lower as compared
to the summer operation. Since biological systems exhibit temperature dependence
and since the effluent quality standards necessitate accurate prediction as to the
winter removal efficiencies of a biological system, a complete analysis of the
temperature effects was undertaken and is described in the following section.
Cold Weather Effects on the Biological System
The expanding use of mechanical aerators for oxygenating activated sludge basins
coupled with increasingly stringent temperature and organic effluent criteria
underscores the need for accurately predicting temperature balances in the design
of the regional treatment system. It should first be recognized that a mechanically
aerated activated sludge basin is both a cooling pond and a biological reactor.
As the degree of heat dissipation dictates the equilibrium basin temperature which
in turn influences the efficiency of organic removal via biochemical oxidation,
the importance of temperature prediction is apparent. Paradoxically, many
biological treatment systems are designed with little or no reference to thermal
effects. The purpose of this discussion, therefore, is to present a design approach
for predicting a temperature profile across a mechanically aerated basin, and
estimate the resultant biological removal capacity and effluent quality of the
system based on the data accumulated during the winter pilot plant studies.
General Review;
A review of pertinent historical information is necessary in order to provide a
basis for developing a rational temperature-prediction approach. As heat
loss from mechanical aerators, temperature effects on biological systems, and
regulatory constraints with respect to effluent temperature and organic residuals
are all interrelated, each of these aspects is included in this review.
231
-------
PERCENT BOD5-COD REMOVAL (TOTAL)
vs. AERATION TIME
10
CO
KJ
100
§80
2
LJ
cr
o
860
I
m
Q
O
CD
H40
UJ
O
tr
20
A
O BOD5-SUMMER CONDITIONS
A COD-SUMMER CONDITIONS
1
I
1
8 10 12 14
AERATION TIME (hours )
16
18
J
20
CO
i
00
-------
PERCENT BOD -COD REMOVAL (ACROSS
AERATION TANK) vs. AERATION TIME
100
to
CO
CO
§80|—
O
2
UJ
(T
O
§601-
O
CD
40
UJ
O
tr
UJ
a.
20
O BOOg- SUMMER CONDITIONS
A COD-SUMMER CONDITIONS
1
I
I
8 10 12 14
AERATION TIME (hours )
16
18
J
20
CQ
C
CO
Oi
-------
Aeration Basin Heat Loss
Mechanical aerators in activated si udge basins serve not only to oxygenate
the mixed liquor, but also to increase heat transfer from the basins. The total
heat dissipated in a mechanically aerated basin is the sum of the losses in the
aerator spray cloud and the losses due to the exposed water surface. Assuming
the usual "water warmer than air" case, the heat loss through a spray cloud can
be estimated by multiplying the enthalpy (heat content) change of the air
flowing the cloud by the air flow rate (Reference 4). The net heat loss at the
exposed water surface is the sum of the evaporation, convection, and radiation
losses less the solar heat gain. This loss can be estimated by the following
equation (Reference 5).
H = 75 (1 + 0.1-W) (Vw - Va) + (1.8 + 0.12 W) (Tw - TQ) - Hs (VI-7)
where:
H = net heat loss (BTU/ft2 x hr)
W = wind velocity (mph) - tree top level
w = vapor pressure of water at temperature Tw (in. Hg)
Va = vapor pressure of water at temperature Ta (in. Hg)
'w= water temperature at surface (°F)
Ta = air temperature (°F)
Hs = average solar heat gain (BTU/ft x hr)
When the equilibrium pond or river water temperature, E, is used, Equation
VI-7 can be modified by setting:
T = E and H = 0
W
therefore:
Hs = 75 (1 +0.1 W) (Ve - VQ) + (1.8+0.12 W) (E-TQ) (VI-8)
substituting in Equation VI-7:
H=75(l +0.1 W)(Vw-Ve) + (1.8 + 0.12 W)(T - E) (VI-9)
where:
E = equilibrium temperature (°F) — i.e., water temperature of
undisturbed pond or river at which H is zero
Ve= vapor pressure of water temperature E (in. Hg)
234
-------
The total heat loss from a mechanically aerated basin can be predicted using this
approach, although several assumptions are required. The validity or degree
of accuracy can be established by comparing actual heat loss in existing systems
to the calculated values.
Temperature Effects on Biological Systems
Temperature influences the rate of chemical and biochemical reactions. In
the range of normal biological activity (5° to 35°C), the biochemical organic
removal rate, K, approximately doubles for each 10°C rise in temperature.
According to the Van't Hoff-Arrhenius equation, K would vary with temperature
as follows:
d In K/dt = Ea/RT2 (VI-10)
where:
K = organic removal rate coefficient
_T = absolute temperature
a = energy of activation constant
R= universal gas constant
The most traditional expression for relating the organic removal rate (via
biochemical oxidation) with temperature is the Phelps equation (Reference 6):
K -K n -ft(T-20)
KT-K20°C^ (Vl-ll)
where:
K KT = organic (BOD) removal rate coefficient at temperature T
20°C= organic (BOD) removal rate coefficient at 20°C
T = liquid temperature, °C
-&•= temperature coefficient
The coefficient, •$, is a function of many variables; namely, the nature of the
wastewater and the type of process. For example, Eckenfelder has reported-6-
values ranging from 1.06 to 1.09 for a temperature range of 10°C to 30°C
(Reference 7). Wuhrmann has reported -0-to be 1.0 for activated sludge,
treating domestic wastes (Reference 8), and Howland has reported-0-to be 1.035
for trickling filters (Reference 9). Based on the pilot plant studies, a-0-approach-
ing 1.05 was calculated. This indicates a more pronounced temperature effect
when treating soluble industrial wastes as compared to treating domestic wastes
of a colloidal and suspended nature. This is logical when considering that the
organic removal via physical entrapment of colloidal and suspended BOD (bio-
235
-------
sorption) on the activated floe is less temperature dependent than the bio-
chemical oxidation of soluble BOD. The results of the pilot plant study plus
reported temperature effects on existing industrial waste activated sludge
plants are shown in Figure 86. This temperature-efficiency relationship
illustrates the importance of recognizing this effect when designing activated
sludge systems, particularly for soluble industrial wastes, and predicting the
effluent quality during the most critical winter months.
Technical Approach and Justification;
The approach for predicting temperatures in mechanically aerated basins as
described herein includes the calculation of heat loss attributable to the
aeration spray and the predicted loss through the surface. The spray heat
loss is calculated from the differential enthalpy of the air flow through the
spray cloud. The cross-^sectional area of the spray pattern exposed to the
air flow from the design mechanical aeration unit must be known, the velocity
of air through the spray estimated, and the approach and exit air temperature
predicted. The surface losses can be estimated by Equation VI- 7 or VI-9
which require climatological data for the area in question. This includes the
selection of design values for relative humidity, wind velocity, ambient air
temperature, solar radiation, equilibrium water temperature (if applicable),
and the influent liquid temperature. Once these two heat loss components
are estimated, the total heat loss can be used to predict the aeration basin
temperature as a function of the influent water temperature. The biological
response in terms of organic removal then can be correspondingly calculated.
In order to establish a valid basis for this procedure, four existing aeration
basins using mechanical aerators were surveyed . Two basins were in Texas and
two were in Illinois. Climatological data, influent and basin temperatures,
and mechanical aerator spray patterns were obtained for each basin. The
calculated heat loss using the aforementioned procedure was then compared
to actual heat loss to demonstrate the degree of accuracy. Example calcu-
lations for one of the four basins-is presented as follows:
Survey Information -
Basin Location Southern Illinois
Wastewater Flow l,300gpm
Wastewater Temperature In 98°F
Wind Velocity (tree top level) 8.1 mph
Aeration Basin Temperature 89°F
Ambient Air Temperature 89°F
Equilibrium Temperature
(based on river temperature) ,82°F
236
-------
NJ
CO
AERATION BASIN TEMPERATURE
vs. REMOVAL EFFICIENCY
gioo
UJ
8 80
UJ
Q.
O
UJ 60
o
40
UJ
tr
in
g 20
CD
n
a
n
o
Q
DRBC
CHEMICAL PLANT "A"
CHEMICAL PLANT "B11
1
1
I
I
1
1
1
0
32
5
41
10
50
15
59
20
68
25
77
30
86
35
95
«C
•F
to
AERATION BASIN TEMPERATURE
-------
therefore:
QA = (6,770,000 ft3/hr) (lb/14.2 ft3) (47.0 - 39.0) BTU/lb
QA = 3,820,000 BTU/hr
The total calculated heat loss Qc = QS + Q^
Qc = 2,360,000 BTU/hr + 3,820,000 BTU/hr
Qc = 6,180,000 BTU/hr as compared to the observed
value, QAct. of 5,850,000 BTU/hr
Similar comparisons were made for the other three basins. These
results are reported in Table 35, indicating the validity of this approach in
predicting the heat loss through a mechanically aerated basin.
Temperature Calculations - Deepwater Regional Plant;
Information Furnished - The proposed activated sludge plant for the
regional system will include mechanical aeration with completely mixed
aeration basins. The first step in estimating the biological removal
efficiency is to estimate the aeration basin temperature using the afore-
mentioned procedure and based on the following conditions:
(1) The climatological data obtained from the weather bureau statioh
closest to the proposed construction site as tabulated in Table 36
and Figure 87.
(2) The temperature of the wastewater into the aeration basin being
in the range of 45°F to 65°F during the coldest day of operation.
(3) Parallel aeration basins will be used. Each basin will receive a flow
of 12.0 MGD, occupy a surface area of 75,250 ft^7 and be oxygenated
and mixed by ten 100 HP slow speed aerators, each having a cross-
sectional spray area of 80 ft .
Information Required - The relationship between the aeration kxssin
temperature and the influent wastewater temperature must be developed
for the coldest month. The design ambient temperature is taken as the
10 percent probability value of the daily mean temperature for the coldest
month. The mean wind velocity for the coldest month and the average
relative humidity for the coldest day will be considered as design values.
The air velocity at the surface is assumed to be half of the tree top value.
238
-------
Dew Point 7Qop
Basin Dimensions 375' x |2Q'
Mechanical Aerators, .five 20 HP fixed mounted, slow speed with
63.3 ft cross-sectional spray area per unit;
Total cross -sectional spray area =5(63.3) = 316.5 ft2
Actual Heat Loss -
Actual Heat Loss, QAch = (1,300 gpm) (8.34 Ib/gal) (60 min/hr)
(98° - 89°)( 8TU )
Ib - OF
QAct. = 5'85M°0 BTU/hr
•••' • • • ;-.•{•* v
Ca|culated Heat Loss - :r
A. Heat Loss from non-aerated surface:
Using Equation VI-9 where Vw @ 89°F = 1 .375 In. Hg
Ve@82°F = 1.106 in. Hg
H=75 [1+0.1(8.1)] [1.375-1.106] +[1.8 + 0.12(8.1) (89-82)]
H=75 (1.81) (.269) +(2 .77) (7)
H=56.2 BTU/ft2/4ir
I
f\
The unaerated area of the basin = 42,000 ft (assuming spray diameter
= 28 ft)
The heat loss from the non-aerated surface, Qs, is therefore:
Q =( 56-2 BTU - ) (42,000 ft2) = 2,360,000 BTU/U
ft2 x hr
B. Heat Loss from the five mechanical aerators, QA, 's:
QA = Air flow (ha in - ha out ) (VI-12)
where:
ha in = enthalpy of air into the spray, BTU/lb
ha out = enthalpy of air out of spray, BTU/lb
air flow = (air velocity at surface of water) (total cross-sectional area of spray)
Assume air velocity at surface equals 50 percent of the air velocity at tree level .
air flow = (4.05 mph) (5,280 ft/mi) (316.5 ft2) = 6,770,000 ft3/hr
ha in =39.0 BTU/lb
ha out = 47.0 BTU/lb at est. 85°F and 90 percent relative humidity
(Conditions for air leaving spray cloud based on spray pond design
given in Perry's Chemical Engineering Handbook, Reference 10.)
239
-------
TABLE 35
AERATION BASIN HEAT LOSS COMPARISON
Aeration Basin No. 1 (Illinois)
Aeration Basin No. 2 (Illinois)
Aeration Basin No. 3 (Texas)
Aeration Basin No. 4 (Texas)
Actual Heat
Loss ,QAct.
BTU/hr
5,850,000
14,300,000
9,120,000
11,000,000
Calculated Heat
Loss, Qc
BTU/hr
6,180,000
11,630,000
10,150,000
13,430,000
TABLE 36
CLIMATOLOGICAL DATA FOR PROPOSED TREATMENT SITE*
Time of Day
0100
0400
0700
1000
1300
1600
1900
2200
AVERAGE
December,
Ambient
Temp.
°F
34
33
32
37
41
40
37
35
36.2°F
1970
Dew
Point
°F
26
25
25
25
25
26
27
27
January
Ambient
Temp.
°F
26
25
24
29
33
33
28
26
27.
, 1971
Dew
Point
°F
17
17
17
18
17
16
17
16
.8°F
February, 1971
Ambient .Dew
Temp. Point
Op op
32 26
31 25
31 25
36 25
41 25
41 26
36 27
34 27
36.3°F
Climatological data from Wilmington, Delaware airport
A. January is the coldest month and considered for design.
B. The probability of the ambient air temperature (daily maximum, mean, and
minimum) being equal to or less than the graph value for the month of
January is shown in Figure 87.
C. The average relative humidity for the coldest day in January is 71.2 percent.
D. The mean wind velocity for January based o.n a ten year average is 9.0 mph
(tree-top level).
E. Solar heat gain = 24 BTU/hr/f>2
240
-------
JANUARY TEMPERATURES FOR WILMINGTON
DEL., BASED ON 20 YEAR PERIOD
DAILY MAXIMUM
TEMPERATURE
DAILY MEAN
TEMPERATURE
DAILY MINIMUM
TEMPERATURE
I 10 50 90 99 99.99
PROBABILITY ACTUAL VALUE IS LESS THAN GRAPH VALUE (%)
(5*
c
CO
-------
Solution - From Table 36 and Figure 87:
Design Ambient Temperature = 21,5°F
Design Relative Humidity = 71.2%
Design Wind Speed = 9.0 mph (tree top level)*
Heat Loss From Exposed Water Surface — Use Equation VI-7; assume1
basin temperatures of 40°F, 50°F/ and 60°F/ and calculate the corresponding
inlet temperatures.
For Tw = 40°F;
H = 75 (1 +0.1)9^.246 - .127) + [l .8 + 0.12 (9.0)]
(40-21.5) -24
H = 17.0 + 53.3 -24
H = 46 BTU/hr x ft2
For Tw = 50° F;
H = 75 [1 + 0.1(9.0)] [.362 - .127] +[1.8 + 0.12(9.0)]
[50-21.5] -24
H = 33.5+82.0 -24
H = 91.5 BTU/hr x ft2
For Tw = 60°F;
H = 75 [1 +0.1(9.0)] [.520-.127] + [1.8 + 0.12(9.0)]
[60-21.5] -24
H=56.0+ 111-24
H = 143 BTUAr x ft2
Heat Loss Due to Aerator Spray —
QA = Air Flow (ha in - ha out)
Air flow through 10 aerators assuming surface wind velocity at 50 percent:
Air Flow = (4.5 mph)(80 ft2/aerator) (10 aerators)
(5,280 ft/mi) = 19,000,000 ft3/hr
*Constrants in Equation VI-7 assume wind speed at tree top level.
242
-------
For air @ 21.5°F and 71.2% relative humidify:
ha in = 6.9BTU/lb
To obtain enthalpy of air leaving spray cloud, the approach to
saturation is estimated at a temperature of 7°F with 90 percent saturation:
40°F 50°F 60°F
Ta out 33°F 43°F 53°F
ha out 11.8 BTU/lb 16.1 BTU/lb 21.5 BTU/lb
air k. 12.4ft3/lb 12.7ft3/lb 13.0 ft3/lb
Applying Equation V1-12;
QA(40°F) = (19,000,000 ft3/hr) (lb/12.4 ft3)(l 1.8 - 6.9)BTU/lb
= 7,500,000 BTU/hr
QA(50°F)= (19/000,000fr3)(lb/12.7ft3)(l6.1 -6.9)BTU/lb
= 13,700,000 BTU/hr
QA(60<>F) = (19,000,000 ft3/hr)(lb/13.0 ft3)(21.5 - 6.9) BTU/lb
v ' 21,300,000 BTU/hr
The Qs values are calculated as follows:
The unaerated area of the basin assuming a spray diameter of 35 feet is:
Area = 75,250 ft - 10 (.785)(35)2
Area = 65,650 ft2 per basin
@ 40°F,46 (_BTU_J(65,650 ft2) = 3,020,000 BTUAr
ft2 x hr
@ 50°F,91 .*(_ BTU ^ (65,650 ft2) = 6,007,000 BTUAr
ft2 x hr
@ 60°F,143 ( BTU )( 65,650 ft2) = 9,388,000 BTU/hr
ft2 x hr
Calculation Summary —
Assumed Basin Temperature 40°F 50°F 6Q°F
Qs, BTUAr 3,020,000 6,007,000 9,388,000
QA, BTUAr 7,500,000 13,700,000 21,300,000
Total Q 10,520,000 19,707,000 30,688,000
243
-------
At a hydraulic flow of 12.0 MGD;
(12,000,000 gpd)(8.34 lb/gal)(day/24 hrs) = 4,170,000 Ib/hr
T = Q/flow
=10,520,000/4,170,000 = 2.5°F
= 19,707,000/4,170,000 = 4.7°F
T60oF = 30,688,000/4,170,000 = 7.4°F
Inlet Temperatures = 42.5°F, 54.7°F, and 67.4°F respectively.
The relationship between the aeration basin temperature and the influent
wastewater temperature for the coldest month is shown in Figure 88. Based
on the observations at the pilot plant during January, 1971, the average
influent temperature to the aeration basins was 52°F during days when the
average ambient temperature was 20°F to 22°F. Assuming the 52°F entrance
temperature, the aeration basin temperature would be 48°F as shown in
Figure 88. The minimum predicted removal efficiency at this temperature,
in terms of BOD, is then 66 percent based on the pilot plant studies as shown
in Figure 86.
It should be recognized that the observed inlet temperature during the pilot
plant studies may be lower than that of an interceptor flow because of the
physical characteristics of the pilot system. Heat losses occurred during
wastewater storage and equalization prior to the aeration system. Since the
proposed regional system will not include storage or equalization, a slightly
higher inlet temperature could be expected even considering losses in the
participant equalization basins and in transmission.
Summary;
In summary, it is obvious that heat loss calculations need to be
considered when formulating the conceptual design for the activated sludge
process treating industrial wastewaters. This is particularly true when specific
effluent criteria must be observed throughout the year. The Delaware River
Basin Commission, in its standards for the Delaware estuary, has limited the
secondary treatment plant efficiency to a two-thirds override of effluent BOD
during cold weather months where the operating temperature falls below 59°F.
Based on this extra allowance, a removal efficiency of approximately 80
percent must be obtained during the winter months to conform with these
standards. As the predicted maximum removal efficiency is 66 percent during
the most severe winter conditions, the biological system alone would not
provide the necessary treatment during this time. Effluent polishing using
activated carbon columns, however, will satisfy this particular effluent
criteria throughout the year.
244
-------
Figure 88
AERATION BASIN TEMPERATURE vs. BASIN
INLET TEMPERATURE FOR JANUARY CONDITIONS
DEEPWATER REGIONAL TREATMENT PLANT
65
UJ
cr
z>
| 60
UJ
CL
UJ
I-
Z 55
(75
m
10% PROBABILITY AMBIENT
OBSERVED INLET TEMPERATURE
AT THE PILOT PLANT
45 50 55 60 65
WASTEWATER TEMPERATURE AT INLET
TO AERATION BASIN (°F)
70
245
-------
Transient Loading Effects on the Biological System
Biological systems, in addition to being temperature dependent, are also
responsive to extreme variations in the organic load applied to the system.
Equalization, therefore, was considered for dampening organic and flow variations
prior to biological treatment. Several aspects of equalization are discussed in
Section V. As most industrial wastewaters have varying organic characteristics
resulting from batch type process operations, chemical spills, etc., the potential
need for equalization at the regional plant site was investigated. Transient loading
studies were therefore conducted at the pilot plant to determine the applicability
of equalization.
Procedure;
The design of the pilot plant incorporated storage and equalization as a
pretreatment process. A 71,000 gallon tank was provided which would
allow a maximum equalization period of 23 hours at a flow of 50 gpm.
The wastewater utilized for the summer loading series was equalized for
23 hours. The data obtained from these special tests served as a basis
for comparing the effects of equalized and non-equalized flow on the bio-
logical system. Prior to the initiation of the winter loading series,
transient loading studies were conducted using only the Chambers Works
wastewater. This wastewater, when neutralized, exhibited many similar
characteristics to that of the combined flow. During these tests, the
equalization tank was bypassed. The analytical and sampling program
remained the same as previously described. The 24-hour composite
samples, however, did not reflect the instantaneous organic variations
that were applied to the biological system.
A second series of transient loading studies was completed during the
winter testing program. The flow regime during this series was such
that the transported wastewater was equalized for 24 hours while the
Chambers Works wastewater had no equalization. This flow regime was
established to represent the regional treatment facility without equalization.
Confirmatory tests, with 24-hour equalization of the total waste flow,
were completed during the terminal phase of the winter studies. The results
of these tests then served as the basis for comparing the equalized and non-
equalized data of the winter tests.
Results;
The results of the summer and winter transient loading studies and the
equalized comparative data are presented in Table 37. With respect to
the summer conditions, the BOD and COP removal efficiencies are almost
246
-------
TABLE 37
TRANSIENT LOADING EFFECTS ON THE BIOLOGICAL SYSTEM
FLOW REGIME
OPERATING ORGANIC
TEMP. LOADING
(°F) Clb BOD/lb MLVSS/dav)
PERCENT BOD
REMOVAL 3
AERATION PROCESS
PERCENT BOD PERCENT COD
REMOVAL 5 REMOVAL
TOTAL AERATION PROCESS
PERCENT COD
REMOVAL
TOTAL
SUMMER CONDITIONS
All wastewater equalized
for 24 hours - 6 hour
aeration detention time 78
Chambers Works as total feed-
no equalisation - 6 hour
aeration detention tine 69
WINTER CONDITIONS
All wastewater equalised for
24 hours - 6 hour aeration
detention time 51.0
All wastewater equalized for
24 hours - 12 hour aeration
detention time. 51.0
Chambers Works wastewater not
equalized. All other wastewaters
equalized for 24 hours - 6 hour
aeration detention time 49.5
Chambers Works wastewater not
equalized. All other wastewaters
equalized for 24 hours - 12 hour
aeration detention time 46.0
Chambers Works wastewater .not
equalized. All other wastewaters
equalized for 24 hours - 12 hour
detention time. 51.0
0.23
0.27
0.82
0.25
0.60
0.19
0.23
54.0
60.0
39.0
65.0
41-2
53.7
72.3
76-0
74.0
46.0
67.0
47.0
55.0
74.0
32.0
42.0
31.3
48.0
21.6
41.7
55.2
52.0
54.0
38.0
52.0
30.7
45.0
57.0
-------
identical at the six-hour aeration detention time. Correspondingly, the
removal efficiencies at six hours during the winter conditions are very similar.
The data presented for the 12-hour detention time tests exhibited some
difference which is primarily attributable to the difference in the operating
temperature of the aeration basin. Based on this information, the variation
in the organic characteristics of the combined wastewater as experienced
at the pilot plant indicated little or no effect on the performance of the
biological system. It should also be recognized that the variations of flow
and wastewater constituents inherent with process operations will be dampened
in the pre-equalization basins of the participants as well as in the conveyance
system.
Summary;
In summary, there is no recommended need for equalization facilities at the
regional treatment plant. Moreover, the proposed treatment facility
will include completely mixed aeration chambers operated in parallel,
providing additional operational flexibility and performance reliability.
Biological System Design Parameters and Coefficients
The pilot scale evaluation program was established not only to predict the reliability
of the biological process, but also to develop the necessary design parameters based
on the performance requirements of the proposed treatment system. The mathematical
models which represent biological systems are presented in Section V of this report
and serve as the basis for the following development of the biological design
parameters.
Application of the STATPK Computer Program
As previously mentioned, computer techniques were utilized in the development
of the biological design criteria. The basic approach in implementing the STATPK
program was to select grouped biological data based on the modes of operation and
environmental conditions, key punch this information on computer cards, and
translate the results into design criteria. Two separate computer runs were made with
the data groups delineated according to organic loadings and temperature conditions.
Upon retrieval of the computer output, a complete review of the information was
made based on the stated statistical significance of the data and the estimation of
steady-state conditions. The design criteria and coefficients were then established
and used for sizing the unit processes and predicting process performance.
Biological Design Coefficients
The biological design coefficients related to substrate removal rates, sludge
248
-------
production and oxygen requirements as determined from the STATPK program
are presented graphically in Figures 89 through 94 and are summarized in
Table 38.
TABLE 38
BIOLOGICAL DESIGN COEFFICIENTS
COEFFICIENT ~
K
K
a
b
a1
b1
-substrate removal rate (day )
(summer conditions)
- substrate removal rate (day "')
(winter conditions)
- Ibs sludge produced/I b BOD-COD removed
- Ibs sludge oxidized/I bs sludge/day
- Ibs oxygen required/1 b BOD -COD removed
- Ibs oxygen requi red/I b sludge oxidized/day
BOD BASIS
0.0115
0.00487
0.445
0.10
0.913
0.0743
COD BASIS
0.00485
0.00367
0.44
0.10
0.699
0.019
By incorporating these design criteria into the mathematical models as presented
in Section V, the aeration detention time, oxygen requirements, and sludge
production can be predicted as follows:
Conceptual Design Calculations
Aeration Detention Time;
(Summer Conditions - BOD basis)
Design basis:
1. BOD of raw wastewater = 230 mg/l (50 percent!le value)
2. BOD removal in primary clarifier = 20%
3. Total removal = 87.5%
4. MLVSS= 1,500 mg/l
249
-------
Figure 89
REMOVAL VELOCITY vs.
EFFLUENT BOD5(SOLUBLE)
0.40 i—
0.35 -
k=O.OII5 day'1
y=O.I25 day'1
k=0.00485 day'1
y=O.I25 day'1
40 60
EFFLUENT BOD5 (mg/l)
100
250
-------
Figure 90
SLUDGE GROWTH RATE vs. REMOVAL
VELOCITY (BOD5 BASIS)
0.20 i—
a=0.445
b=O.IO day"1
-0
BOD5 REMOVAL VELOCITY
251
-------
N
Oi
i-o
0.50
>>
o
UJ
0.40
2 0.30
o
-------
Figure 92
REMOVAL VELOCITY vs. EFFLUENT COD
0.70
0.60
3 0.50
o
X
0.40
o
Q
UJ
> 030
ui
K
o
o
o
0.20
0.10
k»0.00485 doy-l
,y=0.465dayH
k=0.00367 day
y=0.530 day"'
1
100
200 300 400
EFFLUENT COD (mg/l)
500
253
-------
Figure 93
SLUDGE GROWTH RATE vs. REMOVAL
VELOCITY (COD BASIS)
0.20
-0.10
0=0.44
b=O.IOdayH
0.10 0.20 0.30 0.40 0.50
COD REMOVAL VELOCITY, Sj"f* (day""1)
^*i i
254
-------
N>
Oi
Oi
0.501—
UNIT RESPIRATION RATE vs. REMOVAL
VELOCITY (COD BASIS)
0=0.699
b1 =0.019 day'1
I
1
0.10
0.20 0.30 0.40 0.50 0.60
COD REMOVAL VELOCITY, ° * (dayH)
AM!
0.70
CD
-------
Therefore;
S0 = 230 - (0.2) (230) = 184 mg/l
Se = (230) (1 - 0.875) = 29 mg/l
From the STATPK-developed relationship shown in Appendix A, Figure A-2;
t= (So-Se)(24hrs/day)= (184 - 29) (24 hrs/day)
Xa (K Se - y) (1,500) (0.0115) (29) -0.125
t = 12.0 hours
(Winter Conditions - BOD basis)
Design Basis:
1. BOD of raw wastewater = 360 mg/l
2. BOD removal in primary clarifier = 10%
3. Total removal = 66% (observed efficiency during coldest
month)
4. MLVSS = 2,000 mg/l
Therefore;
S0 = 360 - 0.1 (360) - 324 mg/l
Se = 360(1 -0.66) = 122 mg/l
From the STATPK-developed relationship shown in Appendix A, Figure A-2;
f = (S0 - Se)(24 hrs/day) = (324 - 122) (24 hrs/day)
Xa(KSe-y) (2,000) (0.00487) (122)-0.125
t = 5.2 hours
Use a design detention time of 12 hours as summer conditions control.
256
-------
Oxygen Requirements;
Calculated as Ibs 02/ 106 gal
Assume maximum condition - i .e., winter conditions
S0 - Se = Sr = 202 m9/l = 1,690 lbs/106 gal
X a = 2,000 mg/l assuming 12 hour aeration time
then XgV = 8,300 Ibs
Then:
RrV Ibs 02/10° gal = a'S,. + b'XaV
= (0.913)(1,690) + (0.0743X8,300)
= 1,540 + 624
= 2,164 Ibs 02/106 gal
Sludge Production;
Calculated as Ibs sludge/10 gal
Neglecting influent and effluent solids
AX = a SrQ - b V
Assume SrQ = (202 mg/l)(8.34)(l MGD) = 1,690 Ibs/lO* gal
V =(1,500 mg/l)(8.34)(0.5)(l MGD) = 6,250 Ibs
Then;
AX = (0.445)(1,690) -(0.10)(6,250)
AX = 753 - 625
AX= 130 Ibs sludge/106 gal
Use 500 Ibs-sludge/106 gal based on similar installations. Based on the
above calculations, the following parameters would be
257
-------
applicable to the theoretical design of the regional plant using a flow of 72 MGD.
Required Detention Time = 12.0 hours
Total Oxygen Requirement-2'164 tbs °2 (72 MGD) = 155,000 Ibs/day
106 gal
Estimated Sludge Production (VSS, dry wt) = 500 Ibs VSS (72 MQQJ
106gal
= 36,000 Ibs/day
Summary (Biological Treatment)
The results of the pilot plant treatability studies have been presented herein.
These results indicate that a biological system has the capacity to remove the
organic constituents of the combined waste water to a quality level acceptable in
terms of BOD for discharge with the possible exception of cold weather operations.
Additionally, the results indicate that equalization at the regional site is not
required. The proposed biological system will include an aeration detention time
of 12 hours and should be so designed to provide for a completely mixed flow regime,
The observed effluent quality of the biological system is presented in the following
Section and is compared to the effluent quality standards as set forth by the
Delaware River Basin Commission.
PILOT PLANT PROCESS EVALUATION -SLUDGE HANDLING
Various methods of sludge dewatering were evaluated in the pilot plant treatability
program. Included within these studies were dewatering methods such as centri-
fugation, filter pressing and vacuum filtration. Additionally, aerobic digestion
of the biological solids was tested. The results of these evaluations are presented
herein.
Aerobic Digestion
Stabilization of biological solids under aerobic conditions is often termed as
aerobic digestion. The process is widely used to reduce the volatile fraction of
waste solids from activated sludge systems and is most feasible when the volatile
fraction of the suspended solids is greater than 60 percent. In cases where the
volatile suspended solids is less than 50 percent, it is normally not practical to
use this means of sludge treatment. During the process, oxygen is added under
completely mixed conditions, and the biomass is reduced to carbon dioxide,
water, and other end products with very little synthesis occurring. The process
is often called "auto-oxidation" or "endogenous respiration." If primary sludge is
258
-------
introduced into the system, the synthesis and oxygen requirements must be
increased to accommodate the additional load. After aerobic stabilization,
the sludge may be concentrated and dewatered using sand drying beds, vacuum
filters, filter presses, or centrifuges.
Procedure
Aerobic digestion was simulated on a pilot and bench scale level during the
course of this work. In practice, the process is normally conducted on a fill
and draw basis and thus the use of batch techniques is appropriate. The primary
influent feed was shut off from one of the pilot plant aeration basins during the
period of June through July, 1970, and the basin was operated as an aerobic
digester. The bench scale studies consisted of setting up three 8 liter reactors
which are shown in Section V, Figure 7 . Each reactor was supplied with
diffused air. Waste activated sludge was concentrated by gravity prior to being
added to the reactors. During both the pilot and bench scale studies, the
following analyses were made on the mixed liquor; total suspended solids,
volatile suspended solids, oxygen uptake, and pH. Periodically, the BOD^,
COD, TOD, and pH, as well as phosphorus and nitrogen concentrations of the
supernatant liquor were determined. Each of the bench scale reactors was
operated for 20 days and during this period, no additional sludge was added.
Results
The results, as measured by the suspended solids concentration of the reactor
contents and oxygen uptake are presented in Figures 95, 96, 97, and 98.
During the bench scale studies, three different initial solids concentrations
were used. Stabilization efficiencies are shown in Figure 99.
Summary
The data indicate that a maximum of 50 percent VSS reduction could be achieved
in 20 days and that up to a concentration of one percent solids, the solids loading
does not affect the rate of stabilization. Approximately 50 percent of the
volatile solids are not removable during any realistic aeration period as reflected
by the data during the last 10 days of aeration. The low oxygen utilization also
indicates a low rate of cellular destruction through oxidation. This underscores
the importance of thickening either in the digester or prior to digestion in order
to achieve economy in design. A detention time of seven days should be
sufficient to achieve 75 percent reduction of the digestible solids provided the
reactor has facilities for continuous supernating and subsequent thickening of the
contents. The aerobic digestion could be accomplished in earthen basins
provided with surface aeration or in concrete basins provided either with
mechanical or diffused aeration systems. Mixing will control aeration requirements
259
-------
CO
CO
>
I
(O
CO
11', 000
10,000
9000
8000
7000
6000
5000
4000
3000
2000
1000
BENCH SCALE AEROBIC DIGESTION RESULTS
SOLIDS REDUCTION AND OXYGEN UTILIZATION
UNIT I
vss
14
4 2
>v
9
E
UJ
-. a.
•J :D
Z
UJ
g
c, 22232425262728293°3. ' 2
JULY 1970
4 5 6
AUG 1970
-------
BENCH SCALE AEROBIC DIGESTION RESULTS-SOLIDS REDUCTION AND OXYGEN UTILIZATION-UNIT 2
11,000 —
V)
>
i
to
CO
10,000 —
9000
8000
>^
I" 7000
6OOO
5000
4000
3000
2000
1000
vss
- -.5
- -.4
- -.3
Oo UPTAKE-,,
* M n
E
UJ
- -.2
O
>-
X
o
- -.1
* 6 '6 ,7 »
2223242526272829303I ' 2 3 4 5 6
CD
JULY 1970
AUG 1970
-------
BENCH SCALE AEROBIC DIGESTION RESULTS - SOLIDS REDUCTION AND OXYGEN UTILIZATION-UNIT 3
4500
4000
3500
o> 3000
E
CO
co 2500
2000
1500
1000
500
0
\s
02 UPTAKE
VSS
I ' I ' I ' I '' I ' I ' I ' I ' I ' I ' I ' I
.2 »
•3
C
6
E
UJ
UJ
O
>-
X
o
I4.5I6,7I8I9202I2223242526272829303, ' 2 3 4 5 6
JULY 1970 I AUG 1970
-------
CO
PILOT SCALE AEROBIC DIGESTION RESULTS-SOLIDS REDUCTION AND OXYGEN JUT ILIZ AT ION
6000—,
5000—
o»
E
to
I
V)
c/>
I-
4000—
3000—
2000—
1000—
15 (6 17 18 19 go 21 2223 2425 26 2728 29 30 I 2 3 4 5 6 7 8 9 10 II 12 IS H 15 16
JUNE 1970 | JULY 1970
-------
10,000
8,000
Figure 99
AEROBIC STABILIZATION OF VOLATILE SOLIDS
THEORETICAL 50%
REMOVAL
LU
O
I/I
6,000 —
<
*—I
5 4,000
©PILOT PLANT
2,000
I
I
1,000 2,000 3.000 4,000 5,000
FINAL VSS CONCENTRATION, mg/1 - 20 DAYS AERATION
264
-------
and therefore the aeration system should be designed on a basis of approximately
0.15 HP per thousand gallons of aeration volume in the case of mechanical
aerators.
Filter Press
The fixed plate high pressure filter press may be used to dewater waste sludges
produced by municipal water and wastewater treatment facilities as well as
industrial sludges. The process produces filter cakes containing up to 55 percent
solids which are suitable for land disposal or incineration. The economics of the
process are enhanced by thickening prior to pressing and by utilizing incinerator
ash as a conditioner. The press does not dewater solids by squeezing, but operates
similar to a rotary vacuum filter, except higher pressures are used.
Procedure
The filter press process may be simulated by the use of the filter press
"bomb" or a larger pilot plant. However, the larger facility requires a con-
siderable quantity of waste sludge. During these studies, a filter press "bomb"
supplied by Beloit-Passavant was used to investigate the process. Illustrations
of the pilot apparatus are shown in Figures 100 and 101. Three types of waste
solids generated at the pilot plant were utilized for these investigations and in
all cases the sludges were thickened by gravity before testing. The filter press
bomb consists of a nitrogen or CO2 gas cylinder pressure source, a pre-coat
tank, filter feed tank, and a six inch nominal diameter filter. The press
produces a cake about 3/4" thick in the center which tapers off toward the outer
edges. The process has been found more efficient at an elevated pH and therefore
lime was added to the sludges to increase the pH to above 10. In addition, the
process requires sludge conditioning and for these investigations, diatomaceous
earth was used. No attempt was made to optimize the quantity of body feed
required, and therefore the amounts used were in excess of those which would
normally be required. The filtration cycle is preceded by pre-coating the press
with diatomaceous earth. Following the pre-coat, the sludge and conditioning
material combination is pressed onto the filtering medium and the filtrate is
forced through the center with the solids remaining in a cake on the filter.
The maximum pressure used for this investigation was 340 psi, although the normal
operating pressure would be around 230 psi. The operation was continued for 30
minutes at which time filtration was virtually at a standstill.
Results
The results of the pilot investigations are presented in Table 39. The data indicates
moisture contents in excess of 60 percent resulting in a total solids concentration of
about 38 percent. However, approximately half of the solids content of the cases
265
-------
PILOT FILTER PRESS ASSEMBLY
CO
c
5
-------
Figure 101
FILTER PRESS ASSEMBLY
V
267
-------
00
TABLE 39
PILOT SCALE FILTER PRESS RESULTS
BELOIT-PASSAVANT FILTER ASSEMBLY, 6" NOMINAL DIAMETER
WASTE SOLIDS
Activated
Digested Activated
Primary
Primary and
Activated
Body,
Characteristics Feed Water Solids
of Feed Wt. Wt. Wt.
pH2 % Sol ids gm % gm % gm
9.5 1.2 12.6 20.7 38.0 62.5 10.3
11.3 ' 1.5 14.9 24.7 36.8 60.5 10.7
10.9 1.3 11.6 19.1 38.9 64.0 9.3
12.1 1.4 14.4 23.7 39.9 65.5 15.6
Total
Wt.
% gm
16.7 60.9
17.6 62.4
15.3 59.8
25.7 69.9
Filtrate
Volume
ml
7000
7800
7200
7100
1 Diatomaceous earth added for conditioning
2Lime added for pH adjustment
-------
was diatomaceous earth. The best results in terms of the filtrate volume were
obtained using the digested waste activated sludge. However, the filter cake
produced from primary and activated sludge contained the greatest percentage
of sludge solids. It is noteworthy that the pH of this sludge combination was the
highest at 12.1. The highest concentration of feed solids before the addition of
diatomaceous earth was 1.5 percent; however, in practice, these concentrations
might be increased to two to three percent, thereby enhancing the process.
Summary
In summary, the filter press results reflected the highest solids concentrations
obtainable when compared to other dewatering processes which were simulated.
However, it is important to recognize that a great portion of the solids con-
centration consisted of conditioning chemicals. If incineration is not included
in the sludge disposal system, ash or other conditioning chemicals must be
provided. For the most part, the dewatered sludge volumes obtained in the
filter press would be less than those obtained by using other means; however, the
weight in most cases would be greater.
Filter Leaf
Sludge filtration studies using a filter leaf apparatus were conducted in order to
predict sludge yield values for specified operating conditions. Primary sludge,
excess activated sludge, and a combination of the two were used. Although
other sludge dewatering modes were tested more extensively on a pilot scale,
the filter leaf sludge filtration approach provides useful information with respect
to the effect of operating variables on dewaterability. Moreover, the practicality
of using vacuum filtration methods for dewatering the sludges in question can be
assessed.
Samples of primary and excess activated sludge accumulated in the normal
operation of the pilot plant were thickened and taken into the laboratory for filter
leaf testing. The filter leaf apparatus used in this experiment is shown in Figure
102. The predictive equation for filter performance is:
pO-0
1 = 35.7
where:
L = filter loading
P = applied vacuum
cm
269
-------
FILTER LEAF APPARATUS
:lgure 102
VACUUM
GAUGE
TO VACUUM
PUMP
RUBBER VACUUM
TUBING
270
-------
[A— filtrate viscosity
RQ= filter resistance
C = solids deposited per unit volume of filtrate
tf = form, time
The leaf test studies were directed toward the determination of the empirical
constants (1-s)/ rn, and n, as these exponents vary according to the nature
of the sludge. These constants were evaluated by measuring the sludge yield
as a function of operating vacuum, form time, and initial solids concentration.
A bleed valve on the vacuum pump enabled vacuum control. Form time was
obtained by submerging the leaf apparatus in the test sludge beaker for pre-
scribed periods of time. The initial solids concentration was varied by diluting
with sludge filtrate. The procedure used in the performance of this task is
outlined elsewhere (Reference 11).
Data Analysis
The test results for each sludge run are tabulated in Table 40. These data in
turn are plotted in Figures 103, 104, and 105 with the value of the constants
for each sludge noted on the plot. The filter loading values areicalculated on
the basis of form time.
Summary
As indicated by the data, the unconditioned primary sludge, either alone or
combined with excess activated sludge, was not amenable to rapid or effective
dewatering based on the filter leaf test results. It is recognized that the yield
could be enhanced to some extent by the addition of coagulant aid. The excess
activated sludge, however, exhibited higher sludge yields and appears to be
more amenable to vacuum filtration.
The data as presented herein can be used in sizing vacuum filtration units for
the prototype treatment system. Based on the resolution of observed data,
Iquation VI-13 can be used for the general sizing of units, applying the
following exponents as shown in Table 41:
271
-------
FILTER LEAF TEST RESULTS
LU
1.0
.5 .5
.2
: PRIMARY,
1 SLUDGE,
m=2.!5
I 2 345
% FEED SOLIDS
UJ
.1
m-2.6
ACTIVATED
SLUDGE
I 2 3456
% FEED SOLIDS
UJ
5
oc
5
PtL
< C
1.0
E .5
.2
.1
m=l.8
COMBINED
SLUDGE
i i
I 2 345
%FEED SOLIDS
CO
c
8
-------
TABLE 40
VACUUM FILTRATION STUDIES
Initial
Sample
No.
Run No.
1
2
3
4
5
6
7
Run No .
1
2
3
4
5
6
7
Run No .
1
2
3
4
5
6
7
Solids Vacuum Form Time Dry Time
(mg/l) (in. Hg.) (min.) (min.)
Yield Moisture
(gms., dry wt.) C% solids)
1 - Primary Sludge
36,240
36,240
36,240
36,240
36,240
22,000
15,520
2 - Activated
21,280
21,280
21,280
21,280
21,280
12,160
13,600
20
20
20
12
6
20
20
Sludge
20
20
20
12
6
20
20
2
5
10
2
2
2
2
2
5
10
2
2
2
2
1.5
1.5
1.5
1.5
1.5
1.5
1.5
.5
.5
.5
.5
.5
.5
.5
1.659
1.790
3.330
1.312
1 .080
0.565
0.321
3.314
3.408
3.911
2.748
2.938
0.232
0.064
30.0
27.4
23.8
26.0
25.0
26.4
20.0
9.9
9..9
12.5
10.5
10.7
12.6
13.9
3 - Primary-Activated Sludge
26,120
26,120
26, 120
26,120
26, 120
20,800
14,960
20
20
20
12
6
20
20
2
5
10
2
2
2
2
.5
.5
.5
.5
.5
.5
.5
0.758
0.827
2.806
0.126
0.090
0.636
0.169
23.2
24.0
16.7
4.5
24.5
25.6
18.6
273
-------
VI
FILTER LEAF TEST RESULTS
CD
z 0.5 - •,
o .£ /
gj! • As.07Q
£ H °-' ~ X COMBINED
= .05 -r ,SLl!DGE
5 10 20
VACUUM,( in Hg)
e> 1.0 r
1 1 °-5 r
£ ^ 0.2 -
i- ^
0
„ ACTIVATED
I SLUDGE
°*^ • -^^*^7T
-Jl '"S.p
Q:^ 1.0 r 2 ~'18
UJ to
i- -° :
— ' "" n •* -
— O.O 111
^ 0 5 10 20
VACUUM, ( in Hg)
-^=0.30
PRIMARY
SLUDGE
1 l i
5 10 20
VACUUM, ( in Hg)
(Q
C
5
g
-------
FILTER LEAF TEST RESULTS
Figure 105
2.0
1.0
Ocsi
<*£
LJ CO
I- CD
0.5
0.2
O.I
ACTIVATED
SLUDGE
i=0.88
n=0.63
PRIMARY
SLUDGE
I
12 5 10
FILTER FORM TIME, MINUTES
275
-------
TABLE 41
VACUUM FILTRATION CONSTANTS
Sludge , \ , \
(m) (n)
Primary
Excess Activated
Combined
.30
.18
.70
2.15
2.60
1.80
.63
.88
—
Sludge Drying Beds
Although sludge drying beds are a widely applied means of dewatering sludges,
it is believed at this time that area constraints and other factors such as
environmental conditions and sludge characteristics preclude serious consideration
of their installation. However, if subsequent engineering studies dictate their
inclusion in the system, pilot scale evaluation is not deemed mandatory for the
development of process design information.
Centrifugation
Centrifugation, in general, is the use of mechanical equipment that separates
solids from a liquid by sedimentation utilizing centrifugal force. Within the
waste treatment field, centrifuges have been used effectively for sludge thickening
and sludge dewatering with and without chemical addition. It is, however,
difficult to predict centrifuge performance based on bench scale studies because
of the many variables involved and the uncertainties in scale-up. For this reason,
pilot scale centrifuges were installed at the Pilot Plant to evaluate centrifugal
performance in dewatering the primary sludge, the secondary waste activated
sludge which had been aerobically digested, and mixtures of these two sludges.
Three types of centrifuges were rented from the Sharpies Division of the Pennwalt
Chemical Corporation and included a Sharpies P-600 Super-D-Canter solid bowl
type centrifuge, a Sharpies DHL Nozljector disc type centrifuge and a 14"
Fletcher solid bowl basket type centrifuge as indicated in Table 42 and Figure 106.
Each of these units was skid-mounted and equipped with the necessary electrical
gear for operation. In addition, equipment on hand at the Pilot Plant was used as
necessary for feed systems, sludge storage and chemical addition.
276
-------
TABLE 42
CENTRIFUGES TESTED AT THE PILOT PLANT
Model
1. Sharpies P-600
Super-D-Canter
3. 14" Fletcher
Type
Solid Bowl, Scroll
2. Sharpies DHL Nozljector Disc type
Solid bowl with skimmer
Sludges Tested
A) Primary
B) 50/50 combination of primary
and secondary aerobic
digested.
C) 75/25 combination of primary
and secondary aerobic
digested
D) Secondary aerobic digested
A) Secondary digested
B) 75/25 combination of primary
and secondary aerobic digested
A) Primary
B) Effluent from P-600 on 75/25
combination of sludges
-------
Figure 106
PILOT SCALE CENTRIFUGES
P- 600
14 FLETCHER
DHL NOZLJECTOR
CHEMICAL FEED SYSTEM
278
-------
Sharpies P-600 Super-D-Canter Centrifuge
The Sharpies P-600 centrifuge is a conventional type horizontal, cylindrical-
conical, solid bowl machine in which the sludge is fed through a stationary feed
tube along the center of the bowl to the hub of the screw conveyor. The screw
conveyor is mounted inside the rotating bowl and rotates at a slightly lower speed
than the bowl with the use of a planetary gear arrangement. Sludge leaves the end
of the feed tube, is accelerated, passed through the ports of the conveyor shaft,
and distributed to the periphery of the bowl. The solids are settled through the
liquid and are moved along the bowl wall by the blades of the screw conveyor.
The solids move out of the liquid bowl and onto a conical drainage deck and then
are continuously conveyed by the screw to the end of the machine and discharged.
The liquid effluent is discharged through effluent ports after traveling the length
of the pool under centrifugal force. The depth of the liquid or pool volume can be
varied by adjustment of weir plates located at the opposite end of the bowl. In
addition, the P-600 centrifuge has a conveyor designed to add flocculent internally
to the bowl so that the effects of these chemicals can be maximized.
In testing the solid bowl type centrifuge, several independent and dependent
variables must be evaluated including the speed of rotation of the bowl, the speed
of the conveyor with respect to the bowl, the liquid throughput, the solids
throughput, the pool depth, the conveyor pitch, and the amount of flocculent added.
The P-600 centrifuge was designed such that all of these variables could be evaluated
on a pilot scale.
Procedure:
The P-600 centrifuge was installed to provide maximum flexibility in the
testing program as shown in Figure 107. Prior to each test run, the rotation
speed, the backdrive speed, the pool level and the conveyor pitch of the
centrifuge were pre-set. A composite sample of sludge was pumped to the
300 gallon sludge feed tank. The centrifuge was brought up to operational
speed and the sludge feed pump started. A minimum equilibrium time of ten
(10) minutes was allowed for each run before samples were taken of the
centrifuged sludge and centrate. In some cases the flow and flocculent feed
were varied while the centrifuge was in operation thus allowing several tests
to be completed during the same centrifuge run. The samples were analyzed
for solids and moisture content.
Each of the two sludges, the primary sludge and the aerobically digested
sludge, were tested individually with and without flocculent aids. Additionally,
50/50 and 75/25 percentage combinations of the primary and secondary sludge
were evaluated. These various combinations of sludge were tested to provide
additional design information for several alternate ultimate sludge disposal systems,
279
-------
FLOW DIAGRAM FOR PILOT SCALE P-600 CENTRIFUGE
DRIVE MOTOR
300 GALLON SLUDGE
FEED TANK
0-10 GPI-1 SLUDGE
FEED PUHP
CONVEYOR
BACK DRIVE MOTOR
FEED TUBE Jl
i— — —m —
1 II F
M m
I £
*•
f
\
•\ —
kv
3^
•— — — — — "
1
L
\
V PLANETARY GEAR BOX
SLUDGE CENTRATE
DISCHARGE DISCHARGE
FLOCCULANT
FEED PUMP
-------
Results;
The results of the P-600 Centrifuge tests are shown in Figures 108
through 112. Figure 108 presents the results of the primary sludge with and
without the addition of a flocculent. If the flocculent dosage is increased,
the percent recovery increased accordingly. Figure 109 presents the same'
data on the aerobically digested sludge. Again, the percent recovery
increases with flocculent dosage. Figure 110 presents the results of the
combination of the two sludges indicating that the digested sludge has a
higher recovery than does the primary sludge. Figure 111 and 112 present
the 75/25 and 50/50 combination of the two sludges with and without
flocculent addition at varying pool levels.
Fletcher Centrifuge;
The 14" Fletcher solid bowl basket type centrifuge consists of a vertical cylinder
with a sludge storage capacity proportional to the height of the lip ring of the
basket. The sludge is fed into the center of the bowl and is retained in the outer
periphery with the centrate passing over the lip plate. The operation is batch
type in that when the basket is full of centrifuged sludge, the feed is stopped and ,
a sludge skimmer is lowered into the bowl to remove the collected sludge. The feed
is then started, initiating another cycle.
Procedures:
The same feed system was used in operating the Fletcher Centrifuge as the
P-600 except that no flocculents were added to the Fletcher unit. The feed
was started and samples of the centrate were taken on a time basis. As the
basket filled with sludge, the centrate suspended solids also increased. At
this point the feed was stopped and the sludge skimmed from the basket* The
cycle was then repeated.
Results;
Figure 113 presents the results of the Fletcher unit with the primary sludge
and the P-600 effluent from a combined sludge run. As the feed rate was
decreased, the cycle time and percent recovery increased as might be expected.
Sharpies DHL Nozljector
The DHL Nozljector had a recycle clarifier bowl assembly equipped with .050
inch nozzles. With the recycle bowl assembly, it was possible to vary the underflow
or cake concentration by varying the feed rate and recycle rate.
281
-------
PRIMARY SLUDGE RECOVERY CURVES (P-600)*
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Report
-------
NO
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DIGESTED SLUDGE RECOVERY CURVES (P-600)*
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f ,
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COMBINED SLUDGE RECOVERY CURVES (P-600)*
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10.0
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SYM. FEED FEED RATIO
CONG PRIMARY/DIGESTED
O 1.20% 100/0
X 1.62% 75/25
® .61 % 50/55
H .29% 0/100
POLY ADDITION
*/TON
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From
report
(Q
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00
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COMBINED SLUDGE RECOVERY CURVES (P-600)*
10.0 p —i
9.0
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From
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COMBINED SLUDGE RECOVERY CURVES -(P-600)*
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% RECOVERY
SYMBOL
V
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FEED CONC. POLY ADDITION POND
tt/TON
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From
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ro
-------
PRIMARY SLUDGE RECOVERY CURVES-FLETCHER
too
90
80
70
£ 60
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a so
tr
3? 40
30
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0
SYMBOL FEED
Q
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PRIMARY
PRIMARY
PRIMARY
P-600 EFR
FEED RATE
.39 GPM
.65 GPM
1.01 GPM
I.9O GPM
10
15 2O
TIME (MINI.)
25
35
40
(Q
c
-------
Results;
The Sharpies DHL Nozljeclop was able to process secondary aerobic
digested sludge with over 90 percent recovery of the solids without
pol/electrolytes. However/ installation limitations such as pump capacities
and quantity of feed material available did not allow for complete evaluation
of this particular model. The Sharpies DH-5 Nozljector, however, has been
reported to recover 80 percent of the solids in the feed at a flow rate of 200
gpm with a solids increase from one percent to six percent dry solids for
municipal sludges.
Summary (Centrifugation)
Based on the centrifuge pilot program previously described, Sharpies has recommended
a P-5400 Sharpies Super-D-Canter with operating curves fora 75/25 primary-
secondary sludge ratio shown in Figure 114 and a 50/50 ratio shown in Figure 115.
They have included a process requirement summary as shown in Table 43. The
values presented here are indicative of the centrifuge performance using Sharpies
equipment or equal.
Summary (Sludge Handling)
An analysis of aerobic digestion and sludge dewatering by Filter Pressing, Vacuum
Filtration, and Centrifugation has been performed. Aerobic disgestion appears to
be a feasible way of reducing approximately half of the VSS wasted from the
secondary clarifier to the digestor. The digested solids should then be combined
with the primary sludge, thickened, and conveyed to the dewatering facilities.
The pilot tests indicate theft the combined sludge can be thickened to approximately
38 percent solids using a filter press, although the conditioners are included in
this concentration. Influent solids were 1.5 percent, although this concentration
might be increased to two to three percent in practice, thereby enhancing the
process. The leaf tests indicated vacuum filters can dewater the combined sludge
up to a concentration of 20 to 25 percent solids without conditioners. Centri-
fugation will dewater the combined sludge to approximately 12 percent with
or without conditioners. The results of these studies would favor vacuum filtration
or filter pressing over Centrifugation, although the process economics and ultimate
disposal of the sludge itself will strongly influence the selection of the dewatering
system.
PILOT PLANT PROCESS EVALUATION - EFFLUENT POLISHING
Several methods of effluent polishing were evaluated during the pilot plant
program. An extensive evaluation of carbon adsorption was made using both granular
288
-------
ro
CD
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OPERATING RECOVERY CURVE -P5400
75/25 PRIMARY TO SECONDARY SLUDGE RATIO
100 i-
90
80
70
(T 60
UJ
8 50
ui
cr
s? 40
30
20
10
25
50 75 100
P-5400 FEED RATE, GPM
125
ISO
175
-------
OPERATING RECOVERY CURVE -P 5400
50/50 PRIMARY TO SECONDARY SLUDGE RATIO
100 h-
90
80
70
K>
8
50
40
30
20
10
0
25
50 75 100 125
P-5400 FEED RATE, GPM
150
175
(Q
C
-------
TABLE 43
CENTRIFUGE PERFORMANCE SUMMARY
Conditions: Influent suspended solids concentration: 1.6 percent solids
Approximate primary/secondary solids ratio: 75/25
Equipment: Sharpies P-5400
Feed Rate Pol/electrolyte Addition Recovery Cake
GPM Ibs Poly/ton feed solids % % total solids
50 0 54 12
50 2 83 12
50 4 90 12
100 0 42 13
100 2 70 12
100 4 78 12
150 0 35 13
150 2 60 12
150 4 68 12
291
-------
and powdered activated carbon. Additionally, effluent sand filtration and micro-
straining were evaluated. This section describes the procedures followed during
these tests and presents the results as related to design criteria.
Activated Carbon Adsorption Evaluation
In general, two types of experimental procedures were utilized for an evaluation
of activated carbon adsorption as a method of wastewater treatment, namely adsorption
isotherms and adsorption column studies. The amount of substance adsorbed per unit
weight of carbon can be investigated by the preparation of adsorption isotherms.
Isotherms can also be used to develop a general estimate of carbon column efficiency,
though caution must be exercised as other removal phenomena occur in actual column
operations. The prime advantage of adsorption isotherm studies is that they can be
performed on a batch basis and thus provide a rapid method for screening the relative
efficiencies of various carbon types and the susceptability of a given wastewater to
treatment.
Conversely, adsorption column studies require considerable equipment and extended
periods of operation for the development of meaningful data. Column studies are
however, the best available method for developing design criteria for a specific
wastewater.
Adsorption Isotherm
A series of adsorption isotherm experiments were performed to investigate the
feasibility of carbon adsorption as a method of treatment. Additionally, this
method was utilized to screen several types of commercial carbon to determine which
was the most effective. Tests were performed on untreated wastewater, wastewater
after neutralization and primary settling and effluent from the pilot biological
treatment unit.
Adsorption isotherm tests were performed by mixing predetermined amounts of
activated carbon with a solution of known contaminant concentration. The batch
system was then mixed until adsorption equilibrium had been reached after which
the final concentration of the contaminant in solution was determined.
When this procedure is followed for a given wastewater using several different
carbon dosages, the results will generally conform to the Freundlich isotherm,
described by Equation VI-14,
292
-------
where x/m is the carbon loading in Ib. of contaminant per
Ib. carbon, c is the equilibrium concentration and
k and n are constants.
If plotted on log-log paper, the data normally defines a straight line which is
representative of the capacity of the carbon to adsorb a given contaminant from
the wastewater for a given initial concentration. Since powdered activated carbon
is generally mixed with the wastewater to be treated in precisely the same manner
as the test procedure, the adsorption isotherm gives a direct measurement of the
carbon dosage required to reach a given purity level. However, in the application
of granular activated carbon in columns, other removal mechanisms occurred and
isotherm studies can provide only a generalized estimate of the results to be
expected.
Normally, powdered activated carbon is used to perform isotherm studies because
equilibrium is attained more rapidly and reliable results can be obtained within
30 minutes of contact. However, isotherms developed using powdered carbon are
not always representative of what would occur using granular material. Because
granular carbon exhibits a much lower adsorption rate than the powdered material,
a sufficient contact time must be allowed.
Tests were performed to determine the contact time required for several types of
granular activated carbon to reach adsorption equilibrium in samples of untreated,
primary and secondary effluents. In all cases equilibrium occurred within three
hours of contact.
Based upon the results of these studies, isotherms were performed using raw waste-
water, primary effluent and secondary effluent with three brands of activated carbon
and allowing three hours for equilibrium to be obtained. The adsorption isotherms of
powdered carbons were also determined. Performance was measured in terms of COD
and color as determined by platinum-cobalt standards.
Results of the Adsorption Isotherm Studies;
The results of the batch adsorption studies are presented graphically in
Figures 116 through 121, with associated carbon capacity estimates summarized
in Table 44. Plotting of the batch adsorption data in the Freundlich isotherm
format allows the rapid estimation of carbon capacity at exhaustion for a given
influent concentration of contaminant. Perhaps the most pertinent development
of the batch adsorption studies is that the resulting estimates of adsorptive
capacity generally fall in the range indicative of economically feasible activated
carbon treatment.
This conclusion was reached by virtue of the fact that existing carbon
293
-------
Figure 116
ADSORPTION ISOTHERM - COO UNTREATED WASTEWATER
-5
o
00
ct
<
o
CO
o
UJ
o
o
CJ
CO
.02
o — —
A —m.
O——
GRAND DARCO 8 X 35
GRAND DARCO 12 X kQ
CALGON 8 X 30
WESTVACO 12 X kO
30
50
100
C (COD) MG/L
500
294
-------
Figure 117
ADSORPTION ISOTHERM - COD PRIMARY TREATMENT EFFLUENT
.5
8
oc.
o
03
1.10
o
o
QQ
.05
,02
_ o-
A.
D-
GRAND DARCO 8 X 35
GRAND DARCO 12 X 40
CALGON 8 X 30
WESTVACO 12 X 40
30
50
100
C (COD) MG/L
500
295
-------
Figure 118
ADSORPTION ISOTHERM - COD BIOLOGICAL TREATMENT EFFLUENT
.5
o
CO
a.
CO
i •lo
UJ
OL
O
O
CD
.05
02
I I I I I I I
I I
GRAND DARCO 8 X 35
GRAND DARCO 12X^+0
CALGON 8 X 30
WESTVACO 12 X 1*0
i i i
30
50
100
C (COD) MG/L
i i
500
296
-------
ADSORPTION ISOTHERM - COLOR UNTREATED WASTEWATER
to
.7
.5
8
OL
>
o
O
- _l
O
<_>
u. . 10
o
T
T
T 1 1 1—I I I
O ——
GRAND DARCO 8 X 35
GRAND DARCO 12 X 40
CALGON 8 X 30
WESTVACO 12 X 40
• 05
.03
10
/
•
1—I—I—I I I
I I I I I
i i i i i i
50 100
C (COLOR) UNITS
500
1000
CO
I
-------
ADSORPTION ISOTHERM - COLOR PRIMARY TREATMENT EFFLUENT
38
.7
.5
T 1 I
o
A
a
GRAND DARCO 8 X 35
GRAND DARCO 12 X 4
CALGON 8 X 30
WESTVACO 12 X
o
LU
>
O
LU
cc
CC
O
. 10
.05
.03
i i i
j i i i i
50 100
C (COLOR) UNITS
500
1000
-------
ADSORPTION ISOTHERM - COLOR BIOLOGICAL TREATMENT EFFLUENT
10
>o
*o
.7
• 5
o
CD
OC.
i I I I r
GRAND OARCO 8 X 35
GRAND DARCO 12 X 40
CALGON 8 X 30
WESTVACO 12 X
i i r
• 05
.03
10
i i i i i i
50 100
C (COLOR) UNITS
J 1 I
500
1000
CD
i
-------
TABLE 44
ACTIVATED CARBON CAPACITIES FROM ISOTHERM STUDIES
NEUTRALIZED SECONDARY EFFLUENT
PRIMARY Six-Hour Twelve-hour
PARAMETER RAW WAST EWATER EFFLUENT _ Detention Detention
COD
(1) Influent
concentration
530 410 320 250
(2) Capacity
Range I bs COD/
Ibs Carbon 0.20 to 0.45 0.175 to 0.440 0.26 to 0.42 0.170 to 0.275
COLOR
(1) Influent
concentration
(color units) 700 550 500 500
(2) Capacity
Range
units/mg
carbon 0.39 to 2. 80 0.43 to 0.65 0.2 to 0.6 0.17 to 0.44
300
-------
treatment facilities operate in the range of 0.25 to 0.5 pounds of COD
removed per pound of carbon regenerated. Experience has indicated that
carbon utilization in full scale facilities is 50 to 100 percent more efficient
than was predicted from adsorption isotherms. Even without this 50 to 100
percent surcharge, the carbon capacity estimates shown in Table 44 fall within
the accepted range of economic feasibility. Considering Table 44, increasing
the degree of pre-treatment had little effect upon carbon capacity, except in
the case of color removal, where neutralization and primary settling actually
appeared to increase adsorption capacity. The apparent decrease in capacity
experienced when biological treatment was extended from six to twelve hours
can be attributed to a reduction in assumed influent concentration, rather
than a significant change in adsorptive capability. In all cases, the isotherm
indicated that the organic contaminants responsible for color in the wastewater
are selectively adsorbed. Therefore, color removal should be relatively more
efficient than the removal of the entire spectrum of organic contaminants as
reflected by COD. As expected, the smaller particle size of the 12 x 40 mesh
granular carbon exhibits the greatest capacity for both COD and color due to
its larger surface area.
The granular carbon produced by the Westvaco Corporation consistently
exhibited superior capacity for COD, whereas, Grand Darco carbon manu-
factured by the Atlas Chemical Company was superior in color removal
capabilities. Based upon these results, Westvaco 12 x 40 carbon was selected
for bench scale column studies. However, other factors, such as a chemical
resistance and durability must be considered for the final selection of granular
carbon for full scale facilities.
Bench Scale Carbon Column Studies
A series of four carbon column experiments were performed to further evaluate the
feasibility of carbon sorption as a treatment process. Additionally, data was
gathered to develop design criteria for cost analysis purposes. Three of the experiments
utilized the down flow packed column mode of contact, two of these being performed
upon effluent from the pilot biological treatment plant in order to evaluate activated
carbon in a purely tertiary treatment role. The third down flow experiment was
conducted upon wastewater that had received neutralization and primary sedimentation.
Another study was performed using the upflow expanded bed mode of contact, the
influent to the columns being raw wastewater.
Six 2.9 inch I. D. Plexiglas columns six feet in length and associated stainless steel
tubing and valving composed the major elements of testing equipment. Prior to
beginning an experiment, each column was loaded with five pounds of activated
carbon to an average depth of 44 inches. Flow through the columns was provided
301
-------
by a small variable speed centrifugal pump, with flow rate measurement accomplished
by a rotameter. Valves were strategically placed in the piping system so that
individual columns could be backwashed at essentially any desired flow rate using
the variable speed pump. Effluent from the final column was collected and stored
for bqckwashing. In the down flow mode of contact, the first column was back-
washed weekly as dictated by head loss.
During the course of experiments using raw wastewater as the influent, a slip stream
from the equalization tank discharge line was routed to the surge tank adjacent to the
carbon columns. The column feed pump then took suction from the surge tank. On
subsequent experiments, primary and secondary effluents were siphoned from the
primary and secondary clarifiers for discharge to the surge tank. The continuous
column test apparatus is shown in Figure 122.
i
Sampling and Analysis Schedule;
Influent to the columns and effluent from the final carbon columns were
sampled twice daily. Influent grab samples were taken from the surge tank,
whereas effluent from the final column was stored under refrigeration and
the resulting composite sampled. The effluent from intermediate columns
Was sampled on a daily basis. The volume of through-put was recorded twice
daily in conjunction with the sampling effort.
Chemical oxygen demand was the only parameter investigated during
experiments using effluent from the primary clarifier. However, a much more
inclusive analysis schedule was followed for the other experiments. The
schedule included analysis for the following parameters:
a. Chemical Oxygen Demand
b. Total Organic Carbon
c. Total Oxygen Demand
d. Biochemical Oxygen Demand
e. Phenolic materials
f. Total Kjeldahl Nitrogen
g. Total Nitrates
h. Total Phosphates
i. Color (Spectrophotometric)
Discussion of Results;
i
To increase clarify and reduce the volume of tabular data, the results
of the column studies are presented in graphical form wherever possible. In
many cases, these graphs depart significantly from the clear cut geometry
302
-------
CARBON COLUMN TESTING APPARATUS
8
CJ
-------
expected from theoretical concepts. These departures from normally
accepted form can be attributable to the following:
v
a) influent concentrations significantly higher than normal municipal
wastewaters;
b) continually changing influent concentrations and characteristics; and
c) the complex makeup industrial wastewater. .
It must be recognized that the development of design criteria from such studies
by necessity should include appropriate safety factors and engineering judgment.
It is recognized that the carbon column experiments were performed on a
wastewater at different stages of pretreatment, and varying results would be
expected. However, several phenomena were found to occur irrespective of
the degree of pretreatment, and therefore, this can be attributed to fundamental
characteristics of the wastewater.
The first of these involves the ease and consistency of color removal by treatment
with activated carbon. This phenomena is indicated to some extent by the
results of the adsorption isotherm studies. The consistency of removal can be
explained by the fact that both physical-chemical and biological pretreatment
steps apparently have little effect on either true color concentration or the nature
of the substance responsible for coloration. The failure of biological treatment
to significantly reduce color indicates that large complex organic molecules
are the causitive agent, and thus easily sorbed by the activated carbon.
Another interesting phenomena is the excessive leakage of certain organic
contaminants irrespective of degree of pretreatment or loading. The normally
expected pattern of organic removal in activated carbon columns entails
essentially complete removal until the zone of adsorption begins to exit the
column. However, in all four column experiments, excessive leakage began
almost immediately and precluded obtaining removal efficiencies exceeding
90 percent for any extended period. Biological pretreatment apparently reduced
the concentration of the offending organic contaminants to levels where
acceptable removal efficiencies could be maintained. In the experiments j
involving raw wastewater and primary effluent, leakage of adsorption resistant
compounds increased with loading producing what appeared to be an initial
break-through. Quite possibly, the leakage is composed predominantly of low
molecular weight organic compounds susceptible to biological removal but
highly resistant to adsorption by activated carbon.
304
-------
As expected, the removal of the primary nutrients, nitrogen and phosphorous,
by carbon sorption was unimpressive. This effect was typified by the removal's
experienced in treating the secondary biological effluent. Apparently, only
that portion of nutrients bound up in adsorbable organic molecules can be
effectively removed. Conversely, the removal of phenol was highly efficient
with effluent concentration never exceeding 0.1 mg/l. These characteristics
are depicted in Figures 123 through 126.
Results of Carbon Adsorption of Untreated Wastewaters
Carbon adsorption studies were conducted on the untreated influent to the pilot
plant. The wastewater was serially routed through six adsorption columns
each containing approximately five pounds of Westvaco 12 x 40 mesh activated
carbon. An expanded bed upflow mode of contact was selected for the tests
in order to eliminate plugging problems. A linear flow velocity of 8.07 gp
was maintained, thereby providing a total contact time of approximately 21
minutes and a carbon bed expansion which varied between 20 and 30 percent.
Other pertinent operation data are summarized in Table 45.
The performance of the columns in terms of BOD, COD, and TOC removal
is graphically depicted in Figures 127 through 131. Considering Figure 127,
it is apparent that effective treatment is not feasible on a BOD basis due to
an excessive leakage of biodegradable organic contaminants. The Initial
effluent from the final column exceeded projected release criteria and leakage
increased linearly to approach influent concentrations. This conclusion is
reinforced by the COD and TOC data plotted in Figures 128 and 129. Judging
from the BOD5/COD ratio of the residual contaminants, they are predominantly
biodegradeable. Apparently, an extension of column length or contact time
would serve only to retard the observed leakage, and within the bounds of
economic feasibility, probably would not provide an effective treatment system.
Column performance data is shown in Figure 130 and 131 in a format to reflect
percent contaminant removal as a function of the cumulative mass of contaminant
applied. These graphs validate the inability of the carbon system to meet
removal criteria. In addition to leakage problems, the removal of sorbable
COD and TOC proved to be relatively inefficient as indicated by measured
carbon capacities at exhaustion of approximately 0.45 Ib COD/lb carbon and
0.1 IbTOC/lb carbon.
Results of Carbon Adsorption of Neutralized Primary Effluent
Six packed columns operating in the downflow series mode of contact were
utilized to evaluate the affinity of neutralized primary effluent for activated
carbon treatment. A total of 30 pounds of Westvaco 12 x 40 mesh carbon was
305
-------
ACTIVATED CARBON COLUMN PERFORMANCE
MACRO-NUTRIENT REMOVAL BY CARBON SORPTION
o 30
_i
* 20
o
i—
~ 10
5 0.50
o
>1S
H- -
2 25
20
15
- c,
- c.
500
1000 2000
VOLUME OF WATER TREATED (GAL.)
3000
-------
PHENOL REMOVAL FROM UNTREATED WASTE WATER
12
11
10
9
8
I"~I"C(
3
2
I
0
MODE OF CONTACT - EXPANDED BED
LINEAR VELOCITY - 8 GPM/FT2
SOO 1 ,000 I,500
VOLUME OF WASTE WATER TREATED (GAL.)
2,000
2,500
-------
PHENOL REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (4.5 GPM/FT'
00
0.8
0.7
0.6
0.5
0.4
i 0.3
o.
0.2
0.1
0
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - k. 5 GPM/FT
2 -
500
1000 1500 2000 2500 3000
VOLUME OF WASTE WATER TREATED (GAL.)
3500
.4000
-------
PHENOL REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (9-8 GPM/FT )
o
1 .2
1 .1
1 .0
0-9
0.8
0.7
~ 0.6
§ 0.5
O.k
0.3
0.2
0.1
0
Q.
MODE OF CONTACT
LINEAR VELOCITY
500 1000 1500 2000 2500 3000 3500
VOLUME OF WASTE WATER TREATED (GAL.)
1*500 5000
(Q
C
CD
-------
ACTIVATED CARBON COLUMN PERFORMANCE
BOD5 REMOVAL FROM UNTREATED WASTEWATER
500
kOO
CO
G
300
o
§ 200
100
0
•o
%
'6
MODE OF CONTACT - EXPANDED BED -
LINEAR VELOCITY - 8 GPM/FT2
I
I
I
500
1000 1500 2000 2500 3000
VOLUME OF WASTE WATER TREATED (GAL.)
3500
WOO
CO
§
K>
"si
-------
1000
900
800
700
600
500
0 400
300
200
100
0
ACTIVATED CARBON COLUMN PERFORMANCE
COD REMOVAL FROM UNTREATED WASTEWATER
o
o
o
0
T
»
I
I
MODE OF CONTACT
LINEAR VELOCITY
I I
EXPANDED BED
8 GPM/FT2 ~l
500
1000 1500 2000 2500 3000
VOLUME OF WASTE WATER TREATED (GAL.)
3500
i+000
-------
ACTIVATED CARBON COLUMN PERFORMANCE
TOC REMOVAL FROM UNTREATED WASTEWATER
500
400
300 -
CO
O
O
MODE OF CONTACT
LINEAR VELOCITY
200 -
100 -
500
1000 1500 2000 2500 3000
VOLUME OF WASTE WATER TREATED (GAL.)
3500 i+000
(Q
3
to
•O
-------
CO
CO
o
o
1-4
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^
1 0
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o
z:
OC
»—
z
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ec
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o.
ACTIVATED CARBON COLUMN PERFORMANCE
COD REMOVAL FROM UNTREATED WASTEWATER AS A FUNCTION OF COD APPLIED
0
10
20
30
40
T ^/
50
60
70
80
90
III l l 1 1 i l l 1 l i l l i
MODE OF CONTACT - EXPANDED BED *-^— —-"A
LINEAR VELOCITY - 8 GPM/FT2 ^^~"~
.-•*^*
A » r ^^^**
3 ^^^
"~ o r ^^""'
= L6 ^^^ A
/A
JD
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^^''" ^> ^*o
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^^ S
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cr
inn i i i l l 1 i 1 i 1 l i i i l i
0 1 2 3 4 5 6 7 8 9 1C 11 12 13 14 15 16 17
CUMULATIVE LOADING (LB- COD APPLIED)
-------
ACTIVATED CARBON COLUMN PERFORMANCE
TOC REMOVAL FROM UNTREATED WASTEWATER AS A FUNCTION OF TOC APPLIED
0
10
1 \J
20
o
o
,— i
x 30
o u
0
_j 50
^ 60
C£.
t—
5 70
o
CL
£ 80
90
i
•
i no c
1 1 1 1 1 /* '
/
MODE OF CONTACT - EXPANDED BED /
LINEAR VELOCITY - 8 GPM/FT2 /
/
- C /
3 /
- C '
6 /
/-
s' /
./ /
s' /
^•^^ Q-X1***'^
/*' ^*
t .-^^^
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CUMULATIVE LOADING (LB. TOC APPLIED) ' !-, ^
-------
TABLE 45
SUMMARY OF TESTING
Column
Experiment
ITEM No. 1
(a) Period of 28 July -
Operation 2 August
(b) Mode of Upflow
contact expanded bed
(c) Influent Raw wastewater
(d) No. Columns six
(e) Flow Rate
(gpm) 0.37
(f) Linear
Velocity
(gpm/fK) 8.068
(g) Ibs carbon/
column
Column No. 1 5
2 5
3 5
4 5
5 5
6 5
TOTAL 30
(h) Volume/
Column (ft3)
Column No. 1 0.175
2 0.175
3 0.175
4 0.175
5 0.175
6 0.175
TOTAL 1 .050
(i) Contact Time(min)
Column No.1 3.55
2 3.55
3 3.55
4 3.55
5 3.55
6 3.55
TOTAL 21 .30
Column
Experiment
No. 2
27 May -
15 June
Down How
Primary Eff.
six
0.20
4.36
5
5
5
5
5
5
30
0.175
0.175
0.175
0.175
0.175
0.175
1.050
6.43
6.43
6.43
6.43
6.43
6.43
38.5
Column
Experiment
No. 3
3 July -
14 July
Down flow
Secondary Eff.
three
0.205
4.50
5
5
5
15
0.175
0.175
0.175
0.525
6.27
6.27
6.27
18.8
Column
Experiment
No. 4
15 July -
23 July
Down Flow.
Secondary Eff.
three
0.45
9.80
5
5
5
15
0.175
0.175
0.175
•^^HVUBIW^M*
0.525
2.88
2.88
2.88
8.65
315
-------
placed in the columns, with influent applied at a rate of 0.2 gpm providing
a total contact time of approximately 38 minutes. The actual performance
data in terms of the COD removal are presented graphically in Figure 132
and 133.
The performance of the carbon columns operating on primary effluent is in
many respects similar to the results achieved with the untreated wastewater.
Even though the removal curve more closely approximates the classical
breakthrough diagram, leakage of adsorption resistant constituents still
greatly exceeds release criteria. Almost immediately following initiation
of the experiment, effluent COD consistently exceeded 150 mg/l with a
BOD5/COD ratio of approximately 0.5. Apparently, neutralization and
primary clarification does not significantly effect the adsorption resistant
compounds found in the untreated wastewater as column leakage per unit of
contact time was determined to be essentially the same.
The plot of percent removal as a function of cumulative COD loading shown
in Figure 133 serves to accentuate the results, for removals dropped rapidly
below 90 percent following a loading of only 0.11 Ib. COD/lb. carbon.
However a classical breakthrough curve developed as the adsorption wave
exited the final column. Carbon capacity at exhaustion reached approximately
0.5'lb COD/lb carbon.
Results of Carbon Adsorption of Biologically Treated Effluent
Two separate downflow packed column experiments were performed upon the
effluent from the biological Pilot Plant. Both experiments were conducted using
three packed columns in series and a total of 15 pounds of Westvaco 12 x 40
mesh activated carbon. Linear flow velocities of 4.5 gpm/ft* and 9.8 gpm/ft
were maintained during the first and second experiments respectively. Empty
bed volume contact times were respectively 18.8 and 8.7 minutes.
As shown in Figure 134, BOD5 concentrations in the final column effluent
during the first experiment never exceeded 10 mg/l. This can, in part,
be attributed to the relatively dilute nature of the effluent. However, a
considerable reduction in BOD/j was accomplished. Evidently, the biological
pre-treatment did not render the wastewater more amenable to carbon adsorption,
but merely removed a large enough portion of the adsorption resistant compounds
to reduce column leakage to an acceptable level.
In order to achieve a breakthrough at the projected release criteria of 20 mg/l
BOD5, throughput was increased by approximately a factor of two for the second
experimental run. This objective was accomplished although complete exhaustion
316
-------
ACTIVATED CARBON COLUMN PERFORMANCE
COD REMOVAL FROM PRIMARY TREATMENT EFFLUENT
CO
VI
5 600
§ 500
o
400
300
200
100
0
/ Xs*
/ *.^
I
.'"
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - k.k GPM/FT'
1 .
500
1000
2000 3000 ^000
VOLUME OF WASTEWATER TREATED (GAL.)
5000
-------
oo
§
ACTIVATED CARBON COLUMN PERFORMANCE
COO REMOVAL FROM PRIMARY TREATMENT EFFLUENT AS A FUNCTION OF COO APPLIED
*x Oy
^ r
*• I
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY -
100 I
10 15 20 25 30
CUMULATIVE LOADING (LB. OF COD APPLIED)
35
-------
CO
NO
60
50 -
5 30
UN
Q
§
20
10
ACTIVATED CARBON COLUMN PERFORMANCE
BOD REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (k.S GPM/FT2)
T
T
T
T
T
T
T
T
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - k.$ GPM/FT'
I
I
I
I
300 900
1200 1500 1800 2100 2400
VOLUME OF WATER TREATED (GAL.)
2700
3000 3300
3600
(Q
C
-------
was never attained as BOD^ removal remained above 60 percent, as shown
in Figure 135.
The performance of the three columns in removing organic contaminants as
measured by COD and TOC is presented in Figures 136 through 139. As
shown/ a relatively low level of column leakage was experienced for both
parameters throughout the first experiment with adsorption zone emergence
noted only in the effluent of the first column. A similar pattern was developed
during the second experiment; however, contaminant loading was sufficient
to essentially exhaust the adsorptive capacity of the lead column. These
effects are further documented by Figures 140 through 143 in which percent
contaminant removal was plotted as a function of cumulative loading.
Graphicarintegration of the areas under the adsorption curves revealed carbon
capacity of approximately 0.7 Ibs COD/lb carbon and 0.25 Ibs TOC/lb carbon.
Color removal performance is shown in Figures 144 through 146. As indicated
in the first two Figures/ the effluent from the columns was essentially a colorless
fluid (irrespective of the extent of coloration of the influent) and breakthrough
with respect to color was never achieved. Actual treatment performance for.
both experiments is shown in Figure 146 where the color of the biologically
treated effluent/ a distinct greenish yellow with a dominant wave length of
575 millimicrons/ was almost completely removed.
Summary:
In summary/ the pertinent results of this series of experiments was the determination
of a highly significant leakage of adsorption resistant compounds when activated
carbon was applied for the treatment of untreated wastewaters or those having
received only primary treatment and neutralization. Perhaps of equal importance,
was the discovery that the wastewater constituents responsible for coloration are
apparently not adsorption resistant and are easily removed on contact with granular
activated carbon.
The experiments conducted with effluent from the biological Pilot Plant indicate
that a workable facility can be designed to remove essentially all effluent
coloration and reduce other organic contaminant concentrations to a level
acceptable for direct release to the Delaware River. Results and conclusions
obtained from this test series were verified by the pilot-scale testing of effluent
polishing by carbon adsorption.
Pi lot Scale Carbon Column Studies
Pilot scale activated carbon studies were performed to supplement and verify the
320
-------
CO
ro
120
110
100
90
80
~ 70
_i
I 60
LA
g 50
co
40
30
20
10
0
ACTIVATED CARBON COLUMN PERFORMANCE
BOD5 REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (9.8GPM/FT2)
I
I
MODE OF CONTACT - DOWN FLOW
t
LINEAR VELOCITY - 9-8 GPM/FT'
I
I
500 1000 1500 2000 3000 4000
VOLUME OF WASTE WATER TREATED (GAL.)
5000
CD
c
-n
(D
CO
On
-------
ACTIVATED CARBON COLUMN PERFORMANCE
COD REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (4.5 GPM/FT2)
210
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - k.$ GPM/FT
-X^ '\'
^>~~. ^ff \
X. -: ^-""S \ r'
^'
900 1200 1500 1800 2100 2400
VOLUME OF WASTE WATER TREATED (GAL.)
2700
3000
3300
-------
ACTIVATED CARBON COLUMN PERFORMANCE
TOC REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (k.$ GPM/FT2)
CO
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - k. 5 GPM/FT
^-x/ X /
300 600
900 1200 1500 1800 2100 2^*00 2700
VOLUME OF WASTE WATER TREATED (GAL.)
3000 3300
Tl
i
CO
VI
-------
ACTIVATED CARBON COLUMN PERFORMANCE
COD REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (9-8 GPM/FT2)
300
250
200
150
O
O
O
100
150
- C,
'1
*
'2
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - 9.8 GPM/FT'
I
500 1000 2000 3000
VOLUME OF WATER TREATED (GAL.)
1*000
5000
-------
ACTIVATED CARBON COLUMN PERFORMANCE
TOC REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT (9-8 GPM/FT2)
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - 9-8 GPM/FT
500 1000
2000 3000 4000
VOLUME OF WASTEWATER TREATED (GAL.)
5000
(Q
I
CO
>o
-------
ACTIVATED CARBON COLUMN PERFORMANCE
COO REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT AS A FUNCTION OF COD APPLIED (9.8 GPM/FT2)
8
i-i
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^U*
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01 23456 789
CUMULATIVE LOADING (LB. COD APPLIED)
T
(Q
C
3
•••
-------
CO
NJ
XI
ACTIVATED CARBON COLUMN PERFORMANCE
TOC REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT AS A FUNCTION OF TOC APPLIED (9.8GPM/FT2)
1 U
20
o
o
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£ 70
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LINEAR VELOCITY - 9-8 GPM/FT2 ^•***^
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CO
ACTIVATED CARBON COLUMN PERFORMANCE
COD REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT. AS A FUNCTION OF COD APPLIED (4.5 GPM/FT2)
10
o
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r- 1
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MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - 4.5 GPM/FT2
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CUMULATIVE LOADING (LB. COD APPLIED)
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CO
ACTIVATED CARBON COLUMN PERFORMANCE
TOC REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT AS A FUNCTION OF TOC APPLIED (4.5 GPM/FT2)
o
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MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - 4.5 GPM/FT2
— m __________ _ C —1
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CUMULATIVE LOADING (LB. TOC APPLIED)
T-
CQ
C
%
•M_l
t
-------
25
ACTIVATED CARBON COLUMN PERFORMANCE
COLOR REMOVAL FROM BIOLOGICALLY TREATED EFFLUENT (k.$ GPM/FT2)
20
15
\
u
ec
ui
a.
10
5 -
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - k. 5 GPM/FT'
<»00
_L
800 1200 1600 2000
VOLUME OF WASTEWATER TREATED (GAL.)
2400
(Q
2800
3200
-------
ACTIVATED CARBON COLUMN PERFORMANCE
COLOR REMOVAL FROM BIOLOGICALLY TREATED EFFLUENT ( 9.8 GPM/FT2)
30
25
20
oc
2 '5
Ul
a.
10
MODE OF CONTACT - DOWN FLOW
LINEAR VELOCITY - 9.8 GPM/FT'
- C.
1
I
500 !000 1500 2000 2500 3000 3500
VOLUME OF WASTEWATER TREATED (GAL.)
<»500 5000
-------
Figure 146
0.375
ACTIVATED CARBON COLUMN PERFORMANCE
COLOR REMOVAL
0.275
0.275
0.300
0.325
VALUES OF X
0.350
0.375
332
-------
data obtained from the bench scale columns. These studies were undertaken using
a three foot in diameter upflow filter shell packed to a seven foot carbon bed
depth. The column was piped to serve as an effluent polishing unit receiving the
effluent from the pilot plant biological system. The carbon used in the column
for these studies was Westvaco 12 x 40 mesh Nuchar, which was the same carbon
used in the bench scale columns. Three different runs were performed in this
test series by varying the hydraulic application rate. The performance of the
column in terms of quality response was recorded, and the results are reported
in this section. A diagram of the test column is shown in Figure 147.
Sampling and Analysis Schedule;
Sampling points established for this test series included the raw waste to the
biological system, the biological effluent, or carbon column influent, and the
effluent from the columns. Grab samples were obtained daily, the volume of
throughput recorded, and the following analyses were performed:
biochemical oxygen demand
chemical oxygen demand
•
a.
b.
c. color
d. pH
e. phenols
f. MBAS
g. total carbon
Discussion of Results:
Three separate runs were performed at various hydraulic loadings, but using the
biologically treated effluent as the charge in each case. The quality of the
effluent from the biological treatment system was representative of what might
be expected from summer operating conditions. Although the organic concentra-
tion would be higher during winter operation as previously noted, the geometry
of the BOD and COD breakthrough curves observed during this test series indicates
that summer conditions can be safely used for establishing a year-round design basis.
The three different test runs will be discussed individually. The observed data from
each run is presented in tabular and graphical form, the results compared to those
from the bench scale studies, and the selection of design parameters finalized.
These parameters are in turn used for establishing the conceptual design of an
effluent polishing system using carbon columns. This conceptual design is presented
in Section VII and serves as the basis for estimating capital and operating costs
which are included in Section VIII.
333
-------
Figure 147
PILOT SCALE CARBON COLUMN
WASTE WASH WATER VALVE
WASH OUTLET-*
EFFLUENT VALVE
WATER INLET VALVE
AIR DRAIN VALVE
AIR INLET VALVE
334
-------
Test Series No. 1 -
Test Conditions:
Wastewater Charge: Biologically treated effluent
Carbon Column: T ,300 Ibs of Westvaco 12x 40 mesh "Nuchar"
Applied Flow: 21.8 gpm
Linear Flow Velocity: 3.08 gpm/ft2
Contact Time: 17.8 minutes
The results of Test Series No, 1 are tabulated in Table 46. The column
effluent in terms of filtered COD as a function of cumulative throughput
volume is plotted in Figure 148. It is noted that the first noticeable break-
through occurred following a throughput of 100,000 to 120,000 gallons. At
the corresponding COD concentration level of 80 mg/l, the cumulative
loading to the carbon is approximately 0.2 Ibs COD applied/lb carbon as
seen in Figure 149. It is noted that the data generated from the bench scale
columns compares favorably with that from the pilot scale columns with
respect to cumulative loading.
The color removal in the carbon column as a function of volume throughput is
plotted in Figure 150. It is observed that any apparent color breakthrough
occurs long after COD breakthrough, which only confirms the results recorded
during the bench scale studies.
Test Series No. 2 -
Test Conditions:
Wastewater Charge: Biologically treated effluent
Carbon Column: 1,300 Ibs of Westvaco 12 x 40 mesh "Nuchar"
Applied Flow: 17.0 gpm
Linear Flow Velocity: 2.4 gpm/ft
Contact Time: 23 minutes
The results of Test Series No. 2 are tabulated in Table 47. The column effluent
in terms of filtered COD as a function of cumulative throughput volume is
plotted in Figure 151. Analysis of this plot indicates multi-phase breakthrough.
This phenomenon is accentuated when the data are plotted in the format of
percent COD removal as a function of volumetric throughput as shown in
Figure 152. This Figure indicates that an apparent initial breakthrough, or
"COD leakage," occurs immediately after initiating operation of the
column. A secondary breakthrough occurs at approximately 30,000 gallons
throughput, and a final breakthrough occurs at approximately 560,000 gallons
335
-------
TABLE 4£
ACTIVATED CARBON COLUMN RESULTS - 3.08 gpm/ft2 (Q = 21.8 gpm)
Sample
No.
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
Date
5/3/71
5/4/71
5/5/71
5/6/71
5/7/71
5/8/71
5/9/71
5/10/71
5/11/71
5/12/71
5/13/71
5/14/71
pH
2.2
7.1
7.6
2.3
7.1
7.0
2.4
7.2
7.2
2.4
7.3
7.2
2.4
7.1
7.0
2.1
7.1
6.9
2.2
7.2
7.0
2.3
7.2
6.9
2.4
7.3
7.1
2.4
7.3
7.1
2.6
7.2
7.4
2.4
7.1
7.1
COD*
ms/1
405
186
29
393
148
45
419
126
41
363
102
37
518
180
65
565
244
77
426
153
72
399
177
80
510
181
96
486
155
92
403
155
72
500
204
76
BOD*
ma/1
183
32
18
162
35
25
146
25
23
144
31
18
170
20
17
223
36
26
227
38
27
205
43
31
199
39
27
189
29
22
199
48
18
198
43
36
Color
USPHS
832
1099
70
832
1099
70
727
1158
136
1311
855
263
998
962
135
-
-
-
1187
1358
212
859
1290
102
1008
2383
230
994
1840
84
939
1027
93
_
-
~
Phenol
mg/1
4.5
1.7
0.10
5.2
0.45
0.095
4.05
0.40
0.05
3.65
0.40
0.12
10.10
0.30
0.09
6.85
0.46
0.05
6.85
0.46
0.05
6.55
0.44
0.06
4.45
0.38
0.08
_
-
-
7.2
0.34
-
_
-
~
MBAS
mg/1
1.98
1.26
0.12
1.35
-
-
2.08
1.19
0.05
_
-
-
-
-
-
-
-
-
2.91
1.68
0.16
2.45
1.53
0.14
1.98
1.52
0.15
_
-
-
-
-
-
1.89
0.99
*""
* COD and BOD values based on filtered samples
601 = raw waste
636 - biological effluent (influent to carbon column)
695 = effluent from carbon column
336
-------
TABLE 46 cont'd.
ACTIVATED CARBON COLUMN RESULTS - 3.08 gpm/ft2 (Q - 21.8 gpm)
Sample
No.
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
601
636
695
601
636
695
601
636
695
601
636
695
Date
5/15/71
5/16/71
5/17/71
5/18/71
5/19/71
5/20/71
5/21/71
5/22/71
5/23/71
5/24/71
5/25/71
5/26/71
pH
2.4
7.0
6.7
2.6
6.9
7.0
2.6
7.0
7.0
2.3
7.1
6.8
2.2
6.9
6.8
2.3
7.4
7.1
2.3
7.3
7.3
2.1
7.2
2.4
7.3
7.1
2.5
7.0
7.0
2.5
7.1
7.0
2.4
6.8
6.9
COD*
me/1
315
118
83
427
142
87
413
165
83
336
154
79
406
141
102
398
168
94
477
131
89
347
126
370
105
97
444
142
92
360
131
76
396
125
83
BOD*
me/1
135
30
26
197
37
35
182
33
23
148
28
18
184
31
22
-
-
-
228
26
22
212
29
_ _ _ w
236
30
26
213
30
21
160
23
17
120
14
5
Color
USPHS
517
601
154
578
523
117
709
691
148
1064
1395
197
1547
1260
271
1238
1414
346
1322
1488
186
621
629
555
810
349
1099
752
405
1130
1030
546
1065
999
334
Phenol
me/1
5.05
0.32
0.06
6.55
0.32
0.11
6.30
6.36
0.13
4.05
0.33
0.11
6.75
0.36
0.15
-
-
-
6.10
0.23
0.15
6.75
0.26
6.75
0.36
0.25
8.70
3.15
0.25
-
-
-
-
-
*™
MBAS
me/1
2.24
0.91
0.15
1.89
1.08
0.20
1.30
1.01
0.20
_
_
-
_
-
-
-
-
-
_
-
-
-
-
..
-
-
-
-
-
-
-
-
-
-
"
* COD and BOD values based on filtered samples.
601 - raw waste
636 = biological effluent (influent to carbon column)
695 = effluent from carbon column
337
-------
TABLE 47
ACTIVATED CARBON COLUMN RESULTS - 2.4 gps/ft2 (Q - 17 gpo)
Sample
No.
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
69-5
601
636
695
601
636
695
601
636
695
601
636
695
Date
1971
6/10
6/11
6/12
6/13
6/14
6/15
6/16
6/17
6/18
6/19
6/20
6/21
6/22
6/23
6/24
pH
2.2
7.3
2.2
7.3
2.1
7.3
2.15
6.85
2.4
7.15
2.2
6.8
2.25
7.1
2.2
7.0
2.3
7.1
2.3
7.15
2.3
6.55
2.45
7.4
2.55
7.4
COD
344
117
(18)
327
121
(40)
365
104
(16)
310
149
(28)
352
128
(35)
356
96
(53):
184
104
(54.5)
424
112
(48)
373
115
414
125
(68)*
382
102
(77)*
263
120
(54)
BOD
122
17.5
121
13.9
138
13.8
122
11.3
99
15.6
119
14.7
148
10.2
138
4.8
165
13.1
174
22
197
11.8
150
7.3
103
9.6
Color
USPHS
1229
722
1382
597
438
683
714
662
1280
859
465
739
1241
694
1114
686
1592
1548
1698
712
1276
911
Phenol
mg/1
4.6
.12
5.0
Trace
6.7
.05
4:8
0.7
5.7
1.6
5.
.03
8.8
0.4
7.5
0.3
1.6
0.25
8.0
0.25
7.8
0.25
MBAS
2.55
1.14
3.17
1.41
3.72
1.75
4.20
1.01
4.4
2.24
3.5
2.86
4.08
2.80
3.8
3.4
2.66
2.73
3.3
3.0
4.2
3.5
TC Gal/
me/1 day
135
63
90
68
16,400
109
62
23,600
129
56
18,000
117
87
24,000
129
56
22,000
26 ,000
126
48
25,900
120
50
24,100
22,300
19,700
120
41
21 ,000
147
35
24,000
26,800
69
26,200
Total
Gal
[8,200)
16,400
[28,200]
40,000
[49,000]
58,000
[70,000]
82,000
(93,0001
104,000
[117,000]
130,000
[142,900]
155 ,9.00
[167,900]
180 ,000
[191,000]
202,300
[212,000]
222,000
[232,500]
243',000
[255,000]
267,000
[280,400]
293,800
[306,900]
320,000
601 raw waste
636 - biological effluent (influent to carbon column)
695 = effluent from carbon column
( ) = average of 4-6 hr grab samples (filtered)
( )*= average of 4-6 hr grab samples (unfiltered)
[ J - total volumetric throughput at midpoint of daily sampling period
338
-------
TABLE 47 (cent)
ACTIVATED CARBOH COLUMN RESULTS - 2.4 Km/ft' (Q • 17 gpO
Sample
No.
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
Date
1971 '
6/25
6/26
6/27
6/28
6/29
6/30
7/1
7/2
7/3
Tll>
7/5
7/6
7/7
7/8
7/9
P»
2.6
7.4
3.4
7.15
2.9
7.15
7.0
2.5
6.2
6.6
2.65
6.45
6.7
3.0
7.2
7.1
2.5
7.0
7.5
2.8
7.3
7.2
3.0
7.0
7.2
2.85
7.05
7.2
2.85
6.9
7.0
~OM>
•«/l
390
112
(62)
347
93
59
(64)
427
110
55
(59)
(70)
(71)
366
122
67
299
115
65
333
107
50
347
115
76
349
111
64
326
120
94
BOD
M/l
168
10.2
105
8.5
148
13.2
6.0
103.
13.8
6.1
133
13.2
6.0
145
13.2
8.1
143
7.5
6.0
84
8.7
6.3
151
10.3
10.4
105
10.8
12.8
Color
DSPHS
1233
993
1057
753
981
1024
263
1128
774
221
708
674
254
1086
746
301
933
349
801
595
606
225
1135
219
240
769
545
268
1106
1001
599
" rti.no! "'
M/l
6.0
.15
4.5
.15
6.0
0.25
0.10
4.2
0.24
0.055
5.5
0.21
0.05
4.9
0.17
0.055
4.75
0.15
0.06
4.05
0.13
0.065
4.45
0.115
0.09
4.75
0.165
0.115
4.1
0.7
0.365
kBfl ~
•g/1
5.3
3.5
3.8
3.24
3.8
3.24
0.84
2.86
2.0
0.95
2.0
2.04
0.85
2.6
2.0
1.11
2.86
2.19
1.5
2.73
2.41
1.11
2.86
2.12
1.33
2.51
1.92
1.33
4.38
3.50
2.80
TC
-8/1
141
44
120
57
24
117
43
30
111
43
33
69
38
22
126
50
35
132
50
37
108
48
32
105
48
31
99
40
31
75
34
29
Gal/ -
day
25,400
24.600
26,700
27,200
25,700
27.200
24.600
24,600
25.800
25,200
24,100
24,600
26,900
25,800
25,300
Total
Gal
(332.700]
345.400
(357..700J
370,000
(383,350]
396,700
(410,300]
423,900
1*36,750]
449,600
(463,200]
476,800
[488,100]
501,400
[513,700]
526,000
[538,900 )
551,800
[564,400]
577,000
[589,500]
601,100
[613,4001
625,700
[639,100]
652,600
[665,5001
678,400
[691,000]
703,700
601 - raw waste
636 - biological effluent (Influent to carbon column)
695 • affluent froa carbon column
( ) - average of 4-6 hr grab samples (filtered)
( )*- average of 4-6 hr grab samples (unfiltered)
[ ] - total volumetric throughput at midpoint of daily sampling period
339
-------
TABLE 47 (cont)
ACTIVATED CARBON COLUMN RESULTS -2.4 gpm/ft2 (Q = 17 gpm)
Sample
No.
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
Date
1971 pH
7/10
6.95
7/11 2.7
7.05
7.05
7/12
7/13 2.8
7.3
7.4
7/14 2.7
7.15
7.15
COD
mg/1
343
136
106
322
127
93
305
47
BOD Color
mg/1 USPHS
9.0 1007
148
10.8
10.8
113 926
4.2 929
6 . 7 956
136 1176
5.4 682
7.7 350
Phenol
rag/I
0.195
7.4
0.26
0.135
6.2
0.19
0.14
7.5
.20
.15
MBAS
mg/1
2.07
3.78
2.60
2.41
4.08
2.94
2.35
3.7
2.24
TC Gal/ Total
mg/1 day Gal
[715,600]
41 23,800
727,500
[738,500]
22,000
749,500
[762,150]
25,300
774,800
118
43 [786,750]
35 23,900
798,700
108
[812,770]
28,100
826,800
601 = raw waste
636 = biological effluent (influent to carbon column)
695 = effluent from carbon column
( ) = average of 4-6 hr grab samples (filtered)
( )*= average of 4-6 hr grab samples (unfiltered)
[ ] = total volumetric throughput at midpoint of daily sampling period
-------
250 r—
150
o>
-------
COD REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT AS A FUNCTION OF COD APPLIED
ACTIVATED CARBON STUDY TEST I (Based on Filtered COO Analysis)
Small Column Test
(July 1970) ,
Vel =4.5 gpm/ft^
Large Column Test
Q = 21.8 gpm „
Vel =3.08 gpm/ft*
I I I I I I I I I I I I
0.0 0.2 0.4 0.6 0.8 1.0
Cumulative Loading (Ibs COD Applied/lb Activated Carbon)
1.2
-------
CO
2500 r—
COLOR VS. VOLUME THROUGHPUT
ACTIVATED CARBON STUDY TEST I
3.08 gpm/ft'1
2000 —
I/)
4->
C
CO
a:
a.
CO
s_
o
o
o
1500
1000
500
Carbon Column Influent
Carbon Column Effluent
o-o
345
Volume Throughput (gallons x 10 )
CQ
Ol
O
-------
COD VERSUS VOLUME THROUGHPUT
ACTIVATED CARBON STUDY - TEST NO. 2
— 120
Q
O
o
Carbon Column
Influent
Q = 17.0 gpm
Carbon Column
Effluent
idealized breakthrough
geometry
Throughput Volume (gal x 10 )
CD
Ol
-------
0
20
1
| 40
CC.
o
o
o
a>
g 60
G.
80
100
C
mu
COD REMOVAL FROM BIOLOGICAL TREATMENT EFFLUENT
AS A FUNCTION OF VOLUMETRIC THROUGHPUT
CARBON TEST NO. 2 . .
* — -»
.
_ • ^j^M^^
/
» /
•J
112345678
Volume Throughput (gal x 105)
CO
§
ol
K)
-------
throughput. Based on this multiple breakthrough curve, a plot representing
carbon capacity (Ibs COD removed per Ib of carbon applied) as a function
of volumetric throughput is presented in Figure 153. Based on this graphical
presentation, the carbon capacity at a COD breakthrough level of 80 mg/l is
approximately 0.23 Ibs COD removed per Ib carbon and the capacity at
exhaustion is 0.25 Ibs COD removed per Ib carbon. This is lower than the
value reported during the bench scale studies, although the applied linear
velocity was correspondingly lower.
Test Series No. 3 -
.;
Test Conditions:
Wastewater Charge: Biologically treated effluent
Column Carbon: 1,040 Ibs of Westvaco 12 x 40 mesh "Nuchar"
Applied Flow: 28 gpm
Linear Flow Velocity: 4 gpm/ft
Contact Time: 14 minutes
The results of Test Series No. 3 are tabulated in Table 48. The column
effluent in terms of filtered COD as a function of cumulative throughput
volume is plotted in Figure 154. It is observed from this figure that a
significant COD leakage occurred immediately after beginning the run, then
the concentration remained at or below 100 mg/l until almost 400,000
gallons of wastewater had passed through the column. The initial breakthrough
is probably attributable to the inordinately high influent COD concentration
at the beginning of the run as well as possible channeling or "short circuiting"
at the incept because of the higher linear flow velocity. As in Test Series
No. 2, a carbon capacity-volumetric throughput curve is developed for
Test Series No. 3. This representation is shown in Figure 155.
Based on these relationships, the carbon capacity at a COD breakthrough level
of 80 mg/l is approximately 0.38 Ibs COD removed per Ib carbon and the
capacity at exhaustion is 0.48 Ibs COD removed per Ib carbon. This is higher
than the value obtained from Test Series No. 2, but still slightly lower than ,
indicated by the bench scale studies. It does indicate, however, a generalized
basis for establishing a design carbon capacity in terms of COD removal which
is necessary for sizing columns and estimating costs.
The color removal in the carbon column as a function of volume throughput is
plotted in Figure 156. No significant breakthrough occurred during the test
run. These results substantiate previous observations that the color-causative
constituents are not resistant to adsorption and are easily removed by means
of granular carbon columns .
346
-------
TABLE 48
ACTIVATED CARBON COLUMN RESULTS - 4.0 gpm/ft (Q . 28 gpn)
Sample
No.
601
636
695
601
636
695
601
636
695
601
636
695
601
636
6»5
601
636
69J
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
601
636
695
Date
1971
7/22
7/23
7/24
7/25
7/26
7/27
7/28
7/29
7/30
7/31
8/1
8/2
8/3
8/4
8/5
8/6
8/7
8/8
8/9
8/10
PH
2.3
8.45
2.5
7.4
7.75
2.55
7.1
7.2
2.55
6.85
7.1
2.85
6.65
2.90
7.05
6.75
7.1
T.O
9.8
6.95
6.95
2.8
6.95
7.0
2.5
7.05
7.05
2.5
7.0
7.0
2.3
7.15
7.15
2.1
6.8
7.0
2.25
6.45
7.2
2.3
6.2
2.7
6.5
2.8
6.9
3.1
6.95
3.1
6.9
2.9
7.1
COD
»K/l
412
340
416
269
105
311
184
107
444
142
71
356
151
(98)
395
163
68
110
82
410
131
49
494
175
82
384
128
62
360
150
85
541
135
83
592
294
109
448
202
73
371
230
(175)
399
206
(165)
373
137
351
121
391
133
326
171
BOO
w/l
160
86
173
94
51.8
60.6
61.5
206
29.0
34.2
125
19.9
106
17.5
10.8
9.0
198
13.2
7.8
195
9.7
6.3
135
9.3
6.0
145
13.9
7.8
145
37
12.5
158
24
10.8
167
37
7.5
121
41
171
22
159
16.3
158
21
182
23
152
19.2
Color
USPHS
677
1,756
903
1,058
151
483
504
729
484
44
915
767
684
672
57
718
70
896
592
99
1,222
668
38
679
551
116
1,042
537
90
1,172
826
95
1,415
1,317
119
1.383
1,588
1,028
2,385
1,062
1,491
Phenol
mg/1
5.6
.2
5.4
.15
.05
5.6
.25
.05
4.15
.3
.05
.4
4.0
4.35
.3
.05
.25
.1
.25
.1
3.65
.3
.1
5.0
.2
.1
3.9
.35
.15
4.75
.2
.05
.35
6.25
.3
5.5
.4
5.3
.35
5.8
.35
5.6
.35
6.3
.35
3.0
.2
9.1
.15
MMS
ms/1
4.9
4.4
4.8
4.2
.13
3.4
4.2
.06
2.8
3.0
.19
1.61
1.75
2.09
1.66
.3
1.53
.3
2.66
3.4
3.3
.3
2.66
.43
2.41
2.04
.43
1.61
1.57
.48
1.5
1.45
.54
1.7
1.26
1.41
1.24
TC
OK/I
120
104
126
72
90
150
83
52
144
61
43
37
153
105
47
24
38
20
114
48
18
114
48
20
154
51
25
126
74
22
129
68
117
57
123
34
111
38
111
48
105
41
Gal/
day
26,495
36,555
40,500
52,670
21,330
29,050
34,350
29,050
32,260
30.460
30,600
32,530
33,500
35,200
38,300
33,800
40,800
36,900
42 ',"-
Total
Gal
(13,247)
26,495
(42,600)
63,050
[83.505]
103,550
(129,500)
156,220
(166,2001
177,550
(192,0001
206,600
(223,600)
240,950
(255,450)
270,000
[286,0001
302,260
(317,300)
332,720
[348,020]
363,320
[379,300]
395.850
[412.300]
429,700
(446,400)
464,600
[483,600]
502,900
[518,400]
536,700
[557,100]
577,500
|596,OOO]
ol4,400
(635,400)
657.130
601 - raw waste
636 - biological effluent (influent to carbon column)
695 » effluent from carbon column
( ) = average of 4-6 hr grab samples (filtered)
( )*. average of 4-6 hr grab samples (unfiltered)
[ J - total volumetric throughput at midpoint of daily sampling period
347
-------
Figure 153
a
o
o
INFLUENCE OF BREAKTHROUGH CURVE
GEOMETRY ON CARBON CAPACITY
ACTIVATED CARBON STUDY - TEST NO. 2
CARBON COLUMN
INFLUENT
CARBON COLUMN
EFFLUENT
41 5 6
V lume Though
•Capacity at Break-
through Considering
Initial Leakage
.25 fe
10
ut (gal x 10)
Caracity at Idea'
Breakthrough
Capacity at
COD of 80 mg/1
Capacity at
Exhaustion
ized
234567
Volume Throughput (gal x 105)
10
348
-------
280
240
eoo
o>
S 160
120
80
COD vs. VOLUME THROUGHPUT
ACTIVATED CARBON STUDY - TEST NO. 3
Q = 28 gpm
2 3
VOLUME THROUGHPUT ( gal x 105 )
(
§
-------
Figure 155
INFLUENCE OF BREAKTHROUGH CURVE
GEOMETRY ON CARBON CAPACITY
ACTIVATED CARBON STUDY-TEST NO. 3
280
240
200
I 160
e
0 120
8
80
40
0
02
-------
1400 -
1200 -
1000
COLOR VERSUS VOLUME THROUGHPUT
ACTIVATED CARBON STUDY - TEST NO.3
Q = 28 gpm
CO
Q.
in
s_
o
o
C3
800
600
400
200
-Effluent
Volume Throughput (gal x 10 )
(Q
-------
Summary;
The design criteria for a conceptual effluent polishing step using fixed bed
carbon columns can be established based on the extensive bench and pilot
scale studies as reported herein. It is recognized that subsequent events may
alter the design basis to some extent, but the information as presented is
considered adequate for the purposes of preliminary design, effluent quality
determination, and cost estimation.
Most of the carbon treat-ability reported in this Chapter in terms of organic
quality has been presented in terms of COD. This is justified based on the
nature and reproducibility of the analytical procedure as compared to BOD.
Moreover, the relationship between BOD and COD for the biological-carbon
systems for similar wastewaters has been previously documented (Reference 12).
This relationship as shown in Figure 157 indicates that at an effluent COD of
80 mg/l, which is possible to obtain through the biological-carbon system,
the effluent BOD will be less than 15 mg/l during summer operating conditions
as confirmed by the data presented in Tables 46 through 48. These levels are
not expected to increase significantly during winter operations, and in any
event, are expected to satisfy the "override" criteria as set forth by DRBC.
The results from the bench and pilot scale studies which influence the
conceptual design of the carbon effluent polishing system are summarized
in Table 49. Based on these numbers, the following criteria are selected
for design:
Design Linear Velocity - 8 gjwn/ft2
This is a higher flow rate than applied to the pilot scale column, but it is
within the range of the bench scale tests. This application rate will provide
for higher carbon utilization as well as enhanced operation with respect to
TSS removal and backwash cycle requirements.
Design Contact Time - 20 minutes
This contact time is justified on the observed bench and pilot scale column
studies.
Design Carbon Capacity - 0.40 Ibs COD removed/Ib carbon
It is observed from Table 49 that the carbon capacity increases with linear
flow velocity. The selected capacity of 0.40 is based on the pilot scale
Test Series No. 3 properly weighted with respect to a higher design linear
velocity and a capacity fora pre-selected breakthrough of 80 mg/l COD.
352
-------
ORGANIC SELECTIVITY THROUGH COMBINED SYSTEMS
CO
Ol
CO
10
AERATION BASIN
RETENTION TIME (hrs)
CARBON - ACTIVATED SLUDGE SYSTEM
ACTIVATED SLUDGE - CARBON SYSTEM
A-
O—
• —A REFINERY NO. I WASTEWATER
—O REFINERY NO. 2 WASTEWATER
REFINERY-PETROCHEMICAL WASTEWATER
CO
I
-------
TABLE 49
SUMMARY OF CARBON CAPACITY VALUES
BENCH AND PILOT SCALE CARBON COLUMNS
Linear Flow
Velocity
TEST DESCRIPTION (gpm/ft2)
Contact
Time
(min.)
Carbon Capacity
( Ibs COD removed \
Ib carbon
@ breakthrough @ ex-
80 mg/l COD haustion
1. Bench scale columns
2.9"x6'-downflow 4.4
2. Bench scale columns
2.9" x 6'-downflow 9.8
3. Pilot scale column
3* diameter - upflow
Test Series No. 1 3.1
4. Pilot scale column
31 diameter - upflow
Test Series No. 2 2.4
5. Pilot scale column
3' diameter- upflow
Test Series No. 3 4.0
18.8
8.7
0.5
0.70
17.8
0.19
0.20
23.0
0.23
0.25
14.0
0.38
0.48
NOTE: Carbon in all cases was granular "Nuchar" 12 x 40 mesh
Conventional Biological Treatment Using Powdered Activated Carbon
The direct-application of powdered carbon to the activated sludge aeration basin
has been the subject of investigation for several years, particularly where effluent
color and residual organics are in question. Because of the circumstances inherent
in the overall study as related to effluent quality, it was determined to evaluate
this approach from the standpoint of organic removal and solids-liquid separation.
The disposal or reconditioning of the sludge-carbon mixture was not included in the
354
-------
scope of the field investigations, although this facet most probably represents
the critical path.
Procedure:
A direct comparison approach was taken in evaluating this system by
operating two parallel biological systems simultaneously; namely, one
with powdered carbon addition and one without. Each of these systems
had a feed rate of 25 gpm, an aeration detention time of 12 hours and
operated under identical environmental conditions. Carbon addition to
aeration tank "B" was accomplished by feeding a powdered carbon slurry
to the tank through a time controlled, air operated, three-way ball valve
arrangement such that a predetermined feed rate was continuously applied
to the system. The MLSS concentration of the powdered carbon system
ranged from 2,000 mg/l to 6,000 mg/l while the MLSS concentration of the
conventional system was controlled at approximately 2,000 mg/l. The
performance of each of the systems was monitored daily in terms or organic and
color removal and sludge settleability.
Results;
The daily results were grouped and summarized over identical operational
periods. This summary is presented in Table 50. As expected, the
powdered carbon system in terms of both organic removal and color removal
outperformed the conventional biological system. Both systems when
tested during the winter months, however, exhibited relatively low organic
removal efficiencies. Additionally, the sludge settleability in terms of
the SVI for the powdered carbon system was markedly lower than that of the
conventional system.
Since both the conventional biological system and the powdered carbon
system were operated concurrently, the environmental conditions affecting
both systems were essentially normalized when considering the comparative
performance of the two systems. Thus, an estimation of the effects of the
carbon dosage could be obtained in terms of additional removal efficiency.
Figure 158 presents the observed additional BOD-COD removed with respect
to the powdered carbon dosage. Figure 159 presents the effluent color results
as a function of carbon dosage.
Summary;
As evidenced by the pilot plant data presented, the addition of powdered
carbon to the aeration basin enhances the overall removal efficiencies
of the biological system. Moreover, sludge settleability and
355
-------
TABLE 50
RESULTS OF THE CONVENTIONAL AND CARBON ACTIVATED SLUDGE SYSTEMS
TEST
PERIOD
INF. BOD*
mg/1
EFF. BOD* PERCENT INF. COD*
mg/1 REMOVAL mg/1
EFF. COD*
mg/1
PERCENT
REMOVAL
INF.**
COLOR
EFF.**
COLOR
SVI POWDERED CARBON
FEED RATE
mg/1
CONVENTIONAL BIOLOGICAL SYSTEM
I
II
III
IV
BIOLOGICAL
I
II
III
IV
141
192
144
193
SYSTEM WITH
141
192
144
193
56
81
76
128
POWDERED
36
61
45
65
58
57
46
34
CARBON ADDITION
73
68
59
66
507
615
533
622
507
615
533
622
269
321
301
394
162
234
195
240
48
48
43
37
68
61
63
61
620
1,062
860
956
620
1,062
860
956
570
995
759
925
87
513
27,3
262
48
49
46
47
26
30
28
29
140
80
100
150
* BOD and COD results based on soluble organics
** Platinum cobalt units
-------
Figure 158
ADDITIONAL BODg-COD REMOVED IN
POWDERED CARBON BIOLOGICAL SYSTEM
o
O
O
a 150
UJ
ft!
u.
o
en
(O
u
o
X.
UJ
100
50
o
O
o
10
o
o
CD
1
1
1
1
40 80 120 160
POWDERED CARBON DOSAGE (mg/l)
200
357
-------
Figure 159
EFFLUENT COLOR vs. POWDERED CARBON
DOSAGE
IZOOi—
40 80 120 160
POWDERED CARBON DOSAGE (mg/l)
200
358
-------
I
color removal are improved . Based on the results of this test, a carbon
dosage in excess of 150 mg/l would be required in oreler to satisfy the
effluent color regulations of 100 units. At this anticipated feed rate, the
spent carbon-biological sludge would necessarily have to be regenerated to
economically compete with alternate color removal systems. The critical
path of this system's applicability, therefore, is the sludge handling phase of
the treatment cycle. The sludge, containing spent carbon, excess biological
mass, and other particulates, must be segregated and the carbon recovered in
an efficient and economical manner. Since this type of regeneration and
recovery has not been attempted on a large scale basis, a forceful recommendation
of the system cannot be made at this time. Additionally, effluent filtration
may be necessary as a tertiary step to this process for the elimination of carbon
fines.
Upfiow Sand Filtration
Sand filtration was demonstrated as an effluent polishing process with the three
foot in diameter upflow filter as described in the Pilot Scale Activated Carbon
Test section of this Section. The filter media gradation from bottom to top is
described as follows:
2.5 cubic feet of 1 1/4" x 1 1/2" gravel, six cubic feet of 3/8" x 5/8" gravel,
seven cubic feet of 2-3 mm sand and 40 cubic feet of 1-2 mm sand. The
filter was operated at three hydraulic loadings of four, six, and eight gpm/ft
utilizing the effluent from the final clarifier of the biological pilot plant.
Procedure
The operational procedures used for each filter run are listed below:
1 . The filter was backwashed prior to each test run. The backwash cycle
included bumping the filter with 30 cfm of air for three to four minutes.
The 100 gpm backwash rate was then continued for an additional six to
10 minutes until a clear effluent was produced.
2. The filtration cycle was initiated. The hydraulic flow rate was
controlled manually with a valve.
3. Turbidfty tesi* were performed on grab samples of the effluent through-
out the filter run. The break point was established when the turbidity
reached a pre-defined level.
359
-------
Results
The data from a typical filter run is presented in Figure 160. The turbidity
remained reasonably constant throughout the filter run until the actual
breakthrough occurred. Organic removal in terms of COD in the run pre-
sented here increased as breakthrough was approached . However/ the
organic removal was minimal across the filter. Additionally, no color
removal was observed during any of the filter tests.
The removal of suspended solids as a function of the hydraulic loading is
presented in Figure 161. As noted/ the total solids accumulated in the sand
media at breakthrough decreased with increased hydraulic loading. However/
since the quality of the effluent from each of the hydraulic loadings was
essentially the same with respect to COD and TSS, the design hydraulic loading
should be based on filter service time and backwash frequency*
Summary
The results of the filtration studies cited here indicate that only minimal
residual organic and color removal can be expected through the filter.
This is reasonable when considering that most organics removed by filtration
are of a coilofdal and suspended nature and the residual organic constituents
of the combined waste are primarily soluble. Based on these results, fil-
tration does not appear to be technically justified on the basis of effluent
quality regulations.
Micros training Pilot Studies
Microstraining pilot studies were conducted as an effluent polishing process
with a Micro-Matic straining system four feet in diameter and two feet
wide. The strainer was fabricated with 12 stainless steel straining assemblies
with a total area of 24 square feet. The water entered the center of the
rotating drum/ flowed through the screens and out the effluent weir box.
As the drum rotated/ the screens were backwashed by means of a spray system
located on the top side of the drum.
Procedure
The procedure followed for each of two test runs entailed pumping the
biological effluent through the straining system while monitoring the influent
and effluent suspended solids. Two separate tests were conducted/ the
first at a flow rate of 21 gpm with 24 square feet of filter area, and the
second at a flow rate of 43.5 gpm with 12 square feet of filter area.
360
-------
Figure 160
TYPICAL RESULTS FOR
PILOT UPFLOW SAND FILTER EXPERIMENTS
£ 20
c
3
>>
4->
£ 10
400
350
o
o
300
-a
•— QJ.—.
3 C -C -i-
« « 4-> I/I
•—•
S-M- ,/,
a. <»- o
•i- S-
o u
Average Influent Turbidity = 59 units
O
Flow Rate = ^
00
O
Influent COD = 361
O
5,000 1:0,000 15,000
Cumulative Flow (gal)
361
-------
Figure 161
CVJ
+J
14-
l-
•<-• CQ •
(O (/)
3 •--
E r-
3 O
t_- oo
3,000
2,000
-a
ai
+-> M-
ITJ O
^1
•o an
> o 4-
o s- --
0.4
0.3
i^-S'0.2
TO
-4->
O
0.1
0
O. OTO
O 3 OJ
S- O -Q
Q S-
0.5
3 TO 4J
to O) M-
i/> i. ~-^
QJ CQ -r-
^ 1/1
O- 4- Q.
TO-
EFFECT OF
'HYDRAULIC LOADING ON
UPFLOW SAND FILTRATION SYSTEM
Hydraulic Loading (gpm/ft )
362
-------
Results
The results of the two test runs are tabulated in Table 51. As noted, the
suspended solids removal efficiency was low during both tests although some-
what better solids removal was experienced at the higher flow rate. Since
the suspended solids from a biological system are quite small, the 20 micron
steel mesh screens were apparently too large to adequately entrap the sus-
pended solids.
Summary
The use of a microstraining system does not appear to be technically justified in
this particular application based on the pilot scale studies.
363
-------
TABLE 51
MICROSTRAINING RESULTS
2
Results At 21 gpm With 24 ft Screen Area
Accumulated
Gallons
5,000
10,000
15,000
20,000
Results At 43.5
Accumulated
Gallons
5,000
10,000
15,000
20,000
25,000
Influent
TSS mg/1
60
40
50
60"
2
gpm With 12 ft Screen Area
Influent
TSS mg/1
80*
70*
60>
70
50
Effluent
TSS mg/1
50
35
40
50
Effluent
fSS ng/1
70
60
45
55
40
*
Samples based on grab type samples - results are tabulated as
mean values.
364
-------
REFERENCES SECTION VI
1. "Residence Time Distribution in Real Systems," Davis Wolf and William
Resnick, I & EC Fundamentals, 2, 287-293, Nov. (1963).
2. Kayser, Rolf, "Comparison of Aeration Efficiency Under Process Conditions,"
Fourth International Conference on Water Pollution Research, Prague,
Czechoslovakia (1968).
3. Ford, D. L., "Oxygen Transfer and Aeration," Process Design in Water
Quality Engineering, Vanderbilt University fl970).
4. Kelly, R. B., "Large-scale Spray Cooling," Industrial Water Engineering,
August/September (1971).
5. Langhaar, J. W., "Cooling Pond May Answer Your Water Cooling Problem,"
Chemical Engineering, August (1953).
6. Phelps, E. B., Stream Sanitation, John Wiley and Sons, New York (1944).
7. Eckenfelder, W. W., Jr., Industrial Water Pollution Control, McGraw-
Hill, New York (\95ST. ;
8. Wuhrmann, K., "Advances in Biological Waste Treatment," Pergamon Press,
Oxford (T963).
9. Rowland, W., "Flow Over Porous Media as in a Trickling Filter," Proc.,
12th Ind. Waste Conference, Purdue (1958).
10. Perry, J. H., Chemical Engineering Handbook, 4th Edition, McGraw-Hill,
New York (1963).
11. Eckenfelder, W. W. and Ford, D. L., Water Pollution Control - Experimental
Proceddres for Process Design, Pemberton Press, Austin, Texas (1970).
12. Buercklin, M. A. and Ford, D. L., "The Interrelationship of Biological-Carbon
Adsorption Systems for the Treatment of Refinery and Petrochemical
Wastewaters," Sixth Conference, International Association of Water
Pollution Research, Jersusalem, June 1972.
365
-------
SECTION VII
CONCEPTUAL DESIGN AND TREATMENT COST ESTIMATES
The conceptual design and subsequent cost estimates of the regional treatment
facility are presented in this Section. The basis for selection of the most
appropriate unit processes to be included in the optimal treatment system was
predicated on economic considerations, process applicability and reliability
as determined by the bench and pilot studies, and the effluent quality and
stream objectives of the Delaware River Basin Commission. The treatment
system developed was based on the current flow estimates totaling 72 MOD and
on the raw wastewater characterization data as presented in Section IV of this
report. It has been determined that the proposed system will meet the necessary
effluent criteria as presented in Section VIII.
The major treatment processes selected include an activated sludges/stem followed
by an activated carbon effluent polishing system. Pretreatment processes include
neutralization followed by primary clarification. Additionally, sludge digestion
and sludge dewatering processes were selected to handle both the primary and
wasted activated sludges. A schematic of the proposed treatment system is
presented in Figure 3:62.
DESIGN CALCULATIONS AND COST ESTIMATES
The design criteria, design calculations, and cost estimates for the major unit
processes are included herein. The design criteria as presented are based on the
results of the pilot and bench studies as discussed in Section VI. The estimated
costs are based on an ENR index of 1400 to be consistent with estimates cited
in the Preliminary Engineering Report and the Interim Pilot Plant Report.
Neutralization
The proposed neutralization system includes a premixing basin prior to a series
of four two-stage neutralization basins. Dolomitic quick lime will be slaked and
added to the appropriate basin as required with a pH controlled feed mechanism.
As this system is necessary for only two of the industrial participants, namely,
the duPont Chambers Works and the duPont Carney's Point Plant, some of the
costs will be borne directly by these two participants. However, the combined
premixing-neurralizarion process is designed to act as a disinfection process as
well, utilizing the available acid as a biocide. Based on the pilot plant data,
367
-------
00
SCHEMATIC OF
PROPOSED ACTIVATED SLUDGE - CARBON ADSORPTION TREATMENT SYSTEM
CARBON TRANSPORT
(DUPONT- CHAMBERS WORKS AND CARNEY'S POINT)
COMBINED .. .... ocr-nviNr
WASTEWATER „ ^TgxSJj
FROM INTERCEPTORS STRUCTURE
1
NEUTRALIZATION /
WITH LIME *\
w \
,
SLUDGE i—
DISPOSAL
"* HAUL TO LANDFILL
'PRIMARY'S. i i f ^v
mmnotjl r B.OLOG.CAL JaBB*SwM t
nOTMUnJ I STABILIZATION \ m^m }
sREMov*i/ L^ 1 y— y
~ 1 I
1
1— M
RETURN ACTIVATED §
SLUDGE &&
\ PRIMARY i JgB
1 SLUDGE g
I ^ — x^ .' ^-^x.
SLUDSE / THICKENING L »_/ SLUDGE I
DEWATERING ~~\ AS FA DIGESTION J
PUMP
STATION
r^
s~^
-o
-o
-o
-6-
~w~
**\^e
L-Th
FIXED
CARBON
1
f ^
U
1
/^ A THERMAL
X. ) REGENERATION
r^^
SCRUBBERS
On
. y—\
P"
r^"
\o-
fc-
cc
FINAL HOLDING
a REUSE BASIN
FINAL EFFLUENT
TO DELAWARE RIVER'
BED
COLUMNS
TI
<5*
C
3
K>
-------
this arrangement will be effective as no fecal coliforms were ever observed in the
influent or effluent during the entire pilot plant study. Therefore, the cost as
presented includes the capital and operating costs of the basins alone and do not
reflect the costs of lime addition or storage facilities. Moreover, only the basin
sizing and power requirements are presented herein.
Process Requirements
Premixing Basin
Flow = 72 MGD
Detention Time = 15 minutes
Power Level for Complete Mixing - 0.4 HP/1,000 gal
Neutralization Basins
Flow = 72 MGD
Number of Basins = 4 two-stage
Detention Time/Stage = 15 minutes
Power Level for Complete Mixing = 0.4 HP/1,000 gal
Design Calculations
Premixing Basin
Calculate basin size using a 15-minute detention time:
Basin Size =(72 x 10° gal/day) (15 min) = 100,000 ft3
(1,440 min/day) (7.48 gal/ft3)
Calculate basin area assuming 12 ft depth with a square
configuration:
Basin Area = 100f000 ft3 = 8,340 ft2
12
Length = Width =\Xs,340 ft2 = 91.3 ft USE 100 ft
Calculate power requirements @ 0.4 HP/1,000 gals
Total HP = H2 ft) (100 ft) (100 ft) (7.48 gal/ft3) (0.4 HP) .A 360
1,000 gal
Use four 100 HP slow speed mixers on 50 ft centers
369
-------
Neutralizing Basins
Calculate Volume of each stage using a detention time of 15 minutes:
V0|um./Sta,» - (72 xlO6 gal/day) (15 min) = ,37 500 ,
Volume/Stage - (4sys,ems) (1f440 min/doy)
Calculate basin area assuming 12 ft depth with a square configuration:
Area= 187,500 gal 2,080ft2
(7.48 gal/ft3) (12 ft)
Length = Width = N/2,080 ft2 = 46 ft USE 50 feet
Calculate power requirements @ 0.4 HP/1,000 gal
HP/stage = 02 ft) (50 ft) (50 ft) (7.48 gal/ft3) (0.4 HP)
1,000 gal
HP/stage = 90 Use one 100 HP slow speed mixer per basin
Design Summary
Premixing Basin
Basin Dimensions = 12 ft x 100 ft x 100 ft
Power Requirements = 4-100 HP mixers
Neutralization Basins
Number of Basins = 4 two-stage basins
Basin Dimensions/Stage = 12 ft x 50 ft x 50 ft
Power Requirements = 8-100 HP mixers — one each stage
Cost Estimate*
Item Est. Cost
i
Concrete and Earthwork $ 390,000
Mechanical (Mixers) 216,000
Electrical 18,000
Piping and Valves 45,000
Structural 40,000
Basin Lining 50,000
Contingencies and Miscellaneous 51,000
Total Capital $810,000
370
-------
Operating Costs 165,000
Fixed Annual Costs 58,000
Total Annual $223,000
* Based on apportioned costs only as described above.
Primary Clarification
The proposed primary clarification system includes 12 parallel basins equipped with
mechanical sludge removal mechanisms. Sludge pumps are provided for solids
removal to the dewatering process. Each basin will have two parallel flight
assemblies designed for both sludge and scum collection.
Process Requirements
Flow = 72 MGD
Number of Basins = 12 rectangular shaped
Detention Time =>two hours
Overflow Rate (not to exceed) = 800 gal/day/ft
Sludge Production = 2,000 Ibs 10° gal @ one percent concentration
(Based on pilot plant observations)
Design Calculations
Calculate surface area per basin assuming an average SWD of 10 feet:
Surface Area = (72 x 10° gal/day)
(12 basins) (800 gal/day/ft*)
Surface Area = 7,500 ft2
Calculate basin length using a maximum width of 40 feet:
Basin Length = 7'500 *2 = 187 ft
40ft
Use 200 ft basins to allow for weir location.
Check detention against a minimum of two hours:
Volume per basin = (10 ft) (40 ft) (200 ft) (7.48 gal/ft2) = 600,000 gal
Detention Time = (600,000 gal]> (24 hrs/day) =2.4 hours
6.Ox 10° gal/day
371
-------
Therefore the detention time is adequate.
Calculate sludge pumping requirements assuming continuous removal at one
percent solids content:
Volume of Sludge = (2,000 Ibs/lQ6 gal) (72 MGD) (IP6 gal)
9 (10,000 mg/l) (8.34 Ibs/gal)
Volume of Sludge = 1,730,000 gal/day
Use four 600 gpm pumps - two operational and two standby. Located in a
centralized pump station.
Design Summary
Number of clarifiers = 12
Basin Dimensions - 10 ft SWD x 40 ft x 200 ft
Pumps = four 600 gpm
Sludge Removal Mechanisms =24-20 ft flight assemblies (two each basin)
Cost Estimate
Item Est. Cost
Concrete & Earthwork $ 1,565,000
Mechanical (pumps & flight assemblies) 876,000
Electrical 15,000
Piping & Valves 190,000
Instrumentation and Controls 23,000
Hand Rails 58,000
Contingencies & Miscellaneous 363,000
•Total Capital $3,090,000
>,
Operating Costs $120,000
Fixed Annual Cost 221,500
Total Annual $341,500
Secondary Biological System
The conceptual design of the secondary biological system includes six completely mixed
aeration basins followed by 12 center-fed circular clarifiers. Three communal pump
372
-------
stations are provided for returning the activated sludge to the aeration basins.
Process Requirements
Aeration System:
Flow = 72 MGD
Aeration Detention Time = 12 hours (based on maximum conditions
during the summer, see Section VI)
Oxygen Utilization = 2,164 Ibs 02/106 gal (based on maximum
conditions during the winter, see Section VI)
Aeration Transfer Efficiency = 2.9 Ibs 02/HP-hr fsee Section VI)
Power Level for Complete Mixing = 0.15 HP/1,000 gal
Sludge Production = 500 lbs/106 gal (see Section VI)
Final Clarification:
Flow = 72 MGD
2
Overflow Rate (not to exceed) = 700 gal/day/ft
Theoretical Detention Time = >two hours
Sludge Return = 50% with 75% possible
Sludge Concentration = one to two percent
Design Calculations
Aeration Basins:
Calculate basin surface area assuming six basins with a depth of 12 feet:
Surface Area = (36xlO°cnn = 66,800 ft2
(6 basins) (7.48 gal/ft3) (12 ft)
Based on aeration requirements as tabulated below, calculate basin
dimensions using ten 100 HP aerators per basin at a power level of 0.15
HP/1,000 gal. Calculate square surface mixing area of each aerator
assuming a basin depth of 12 feet.
373
-------
Surface Area/Aerator = (100 HP) (1,000 gal) = 7 ^ ft2
(0.15 HP) (7.48 gal/ft^) (12 ft) '
Length = Width = 7,427 ft2 = 86 teet
Design each basin with two rows of five aerators at 86 foot centers.
Length of Aeration Basin = 5(86 ft) = 430 feet
Width of Aeration Basin = 2(86 ft) = 172 feet
Use 175 foot width
Aeration Requirements (Oxygen Basin):
Calculate ox/gen required based on a utilization rate of 2,164 Ibs
02/106gal:
Oxygen Required/Basin = (2,164 Ibs 09/I06 gal) (72 MGD)
(6 basins)
= 25,968 Ibs/day
Calculate power requirements at a transfer efficiency of 2.9 Ibs
02/HP-hr:
Power Requiremente/Basin = _ 25,968 Ibs/day
(2.9 Ibs 02/HP-hr)(24 hr/day)
= 428 HP
Aeration Requirements (Power Level Basis);
Calculate power requirements based on a minimum power level of
0.15 HP/1 ,000 gal:
Power Requirements/Basin -<*«10
,
(6 basins) (1,000 gal)
Power Requirements/Basin = 900 HP
Since 900 HP is greater than 428 HP, power level controls; use ten
100 HP aerators and size basin according to power level .
374
-------
Final Clarifier:
Basin Size
Calculate separate clarifications systems for each aeration basin with a
maximum overflow rate of 700 gpd/ft^:
Clarification Surface Area/Aeration Basin =
= 17,150 ft2
(72 x IP6 gpd) = 17 ,cn ft2
(6 basins) (700 gpd/fH)
Calculate surface area using two clariflers per aeration basin:
Surface Area/Clarifier = 17'150 ft2 = 8,575 ft2
Diameter of Each Clarifier = (4) (8,575)
3.14
Diameter of Each Clarifier = 109 feet
Use two 110 foot diameter clarifiers with a SWD of 10 feet, and check
detention time minimum requirement of two hours:
Detention Time/Clarifier =
(3.14) (110 ft)2 (7.48 gal/ft3) (10 ft) (24 hr/day)
(4) (6 x 1G\6 GPD/clarifier)
Detention Time = 2.84 hours, therefore adequate.
Sludge Return Pump Stations:
Design three communal pump stations, each serving four clarifiers with
an operating recycle rate of 50 percent and a maximum recycle rate of
75 percent^
375
-------
Sludge Return Rate/Clarifier = (°-50K6-0x 106 gpd)
(1,440 mi n/day)
Sludge Return Rate/Clarifier = 2,080 gpm
Use three 1,000 gpm pumps per clarifier; two operational and
one stand-by.
Design Summary
Aeration Basins:
Number of Basins = 6
\
Dimensions of Each Basin = 12 ft x 175 ft x 430 ft
Power Requirements = 60 - 100 HP aerators (10 each basin)
Final Clarifier:
Number of Basins = 12
Dimensions of each Basin = 10 ft SWD x 110 ft diameter
Sludge Return System:
Number of Pump Stations = three (each serving four clarifiers)
Pump Requirements = 36 - 1,000 gpm pumps (three per clarifier)
Cost Estimates (Secondary Treatment Facility)
Item Est. Cost
Concrete & Earthwork $8,242,000
Structural 679,000
Mechanical 2,144,000
Electrical 210,000
Instrumentation & Controls 255,000
Valves & Piping 382,000
Contingencies & Miscellaneous 1,608,000
Total Capital $13,520,000
Operating Costs 888,000
Fixed Annual Cost 969,400
Total Annual $1,857,400
376
-------
Design of Effluent Polishing System (Fixed Bed Carbon Columns)
The conceptual design for an effluent polishing system using packed bed, pressure
vessel carbon columns and the basis for design are described herein. The
criteria as listed below are based on bench and pilot scale studies which are
presented in Section VI of this report. The water quality of the columnar influent
represents observed values of the pilot plant biological effluent. The quality
numbers listed below represent higher, and thus more conservative, levels within
the range of observed values.
Quality Criteria (Influent to Columns)
RANGE DESIGN VALUE
COD (mg/l) 60 - 350 250
BOD5 (mg/l) 20-120 100
Temperature (°C) 5-30
TSS (mg/l) 15 - 150 40
Oil Content, mg/l <10
Process Requirements
(From bench and pilot studies and manufacturers' recommendations)
Flow = 72 MGD (50,000 gpm)
Linear Flow Velocity = 8 gpm/ft2 (Section VI)
Contact Time (empty volume) = 20 minutes (Section VI)
Carbon Capacity = 0.40 Ibs COD removed/lb carbon
(assume breakthrough = 80 mg/l COD)
o
Backwash Rate (no pre-filtration) = 15 gpm/ft
Required Carbon/Water Ratio for conveyance
of spent and regenerated carbon = one Ib carbon/gal of water
(per manufacturer's recommendation)
Carbon loss/regeneration cycle = 5% (per manufacturer's recommendation)
Reduction in original carbon
capacity for 20 cycle operation = 10%
(per manufacturer's recommendation)
Regeneration Steam Equipment = one Ib steam/lb carbon regenerated
(per manufacturer's recommendation)
377
-------
Design Calculations
Carbon Columns:
Required Surface Area = (50,000 gpm) ( min x ft ) = 6,250 ft2
8 gal
Use Standard 20 foot diameter column, Area = 314 ft2
Required No. of Columns = (6,250 ft2) (column ) = 20
314 ft2
Use parallel columnar operation, 20 sets. (2 columns per set)
Required empty bed carbon volume per set =
(2500 gpm/set) (20 min) = 6 685 ft3
(7.48 gal/ft3)
Required minimum carbon length per set = ( 6,685 ft ) = 21.3 ft
314 ft2
Allow 50% expansion during backwash = 32 feet
Allow minimum of 7 feet per column for installation of inlet, backwash,
and filter bottom appurtenances. Extra carbon depth allowances are
made to allow singlje columnar operation while second column of series
is being regenerated.
Use a series of two columns per set, 20 feet diameter, x 25 feet deep.
Initial Carbon Inventory:
Initial Inventory/Set =(6,685 ft3) (26 Ibs/ft3) = 173,810 Ibs
Total Initial Inventory = 20 (173,810) = 3,476,300 Ibs
Allowance for Idle Carbon Inventory = 400,000 IJ>s
Total Inventory = 3,876,000 Ibs
Regeneration Requirements:
Virgin Carbon Capacity = 0.40 Ibs COD removed/lb carbon
Average regenerated carbon capacity = 0.40 (.90) = 0.36
Design Loading (COD) = (250 mg/l) (72 MGD) (8.34/10°)
= 150,000 Ibs COD/day
378
-------
COD Exhaustion Rate (assuming breakthrough COD = 80 mg/l)
250-80 )(150/000 |bs/day) = 10
Regeneration Requirement = ( JO^OOO.) = ^^ |h§
0.36
= 11,800 Ibs carbon/hour
Design regeneration furnace for this capacity. The final furnace
selection will depend on carbon storage volume, furnace operating
time, and feed rate as per manufacturer's recommendations.
Furnace Requirements:
Assume 90 Ibs/day carbon to be regenerated per ft2 hearth area:
(Largest furnace available 25' diameter x 12 hearth)
Hearth Area = (283,300 I b carbon/day ) = 3 100 ft2
(90 Ibs carbon/ft2/day )
Steam Requirement = ( 1 Ib steam/lb carbon) (1 1,800 Ibs carbon/hr)
= ll,800lbsAr
Cost Estimate
Item _ Est. Cost _
Earthwork and Concrete 420,000
Inlet Lift Station 280,000
Carbon Adsorber Tanks 5,040,000
Slurry and Fresh Carbon Tanks 210,000
Mechanical (pumps, comp., conveyance,
screening) 280,000
Piping and Valves 2,380,000
Electrical 462,000
Instrumentation and Control 336,000
Structures 273,000
Regeneration Furnaces (2) and Steam Generator 686,000
Carbon Inventory 1,680,000
Contingencies and Miscellaneous 1,518,000
Total Capital $13,565,000
Operating Costs 1,060,000
Fixed Annual Cost 972,500 , n nn
Total Annual Cost _ $2,032,500
379
-------
Sludge Digestion and Dewatering
The selection of sludge handling processor was necessarily based on the
ultimate disposal of the primary and wasted activated sludges. Since sludge
disposal at sea is being curtailed and sludge incineration is not applicable
with respect to the primary sludge, ultimate disposal by land fill was
selected. (Reference Interim Pilot Plant Report, Chapter VII). Filter press
dewatering was selected as the most applicable dewatering process since
it will yield a sludge cake of sufficient dry ness for direct landfill as opposed
to alternate canidate process such as vacuum filtration and centrifugation
(Reference Section VI of this Report). As a pretreatment step, gravity
thickening of the primary and disgested waste activated sludge will be
included. The wasted activated will be aerobically digested prior to
dewatering.
Aerobic Digestion -Wasted Activated Sludge
Process Requirements;
Detention Time = 15 days (Section V) (Section VI)
Volume of Sludge = 500 Ibs/lQo gal
Reduction of Volatile Matter = 50 percent (Section VI)
Power Level in Basin = 0.15 HP/1000 gal
Design Calculations
Calculate Volume of Sludge
Volume = ( 500 lbs/106 gal) (72 MOD) = 36,000 Ibs/day
Calculate Flow Based on One Percent Concentration
F^vf^ 36,OOP Ibs/day x 10° = 432,000 gal/day
(8.34 Ibs/gal) (10,000 mg/l) 7
Calculate Basin Volume with 15 Day Detention Time
Volume of Basin = (15 days) (432,000 gal/day)
= 6,470,000 gals
Using the basin dimensions of the activated sludge aeration basins.
Length =430 ft.
Width = 175ft.
Depth = 12 ft.
Volume = 6,750,000 gal
ttJse 10*100 HP floating type high speed aerators such that the basin depth
can be varied.
380
-------
Gravity Sludge Thickener
Process Requirement's;
Loading Rate (not to exceed) = 10 Ibs solids/ft2 day
Primary Sludge Produced = 144,000 Ibs/day :
Digested Secondary Sludge Produced = 21,600 Ibs/day (40% TSS reduction)
"*» .
Design Calculations;
Calculate surface area of thickener using a loading of lOlb sludge/
ft2day with a SWD = 10ft.
Surface Area =065,600 Ibs sludge/day) = 16 560 ft2
(10lbs/ftz/day)
Use two 100 ft dia basins.
Calculate volume of sludge holding tank assuming a thickened sludge
concentration of 4 percent.
Volume = (162,000 Ibs sludge/day) (106 gal) = 48Of000 gal
(8.34 Ib/gal) (40,000 mg/l)
Assuming 24 hr maximum detention time use one 100 ft dia sludge
storage tank with mixer.
Filter Press
Process Requirements
Dry Solids Concentration of Cake = 45% (See Section VI)
Cake Density = 85 Ib/ft2
Total Sludge per Day = 162,000 Ibs/day
Lime Dosage Required = 10% dry wt of sludge
Ferric Chloride Dosage Required = 5% dry wt of sludge
Design Calculations
- r w , (162,000 Ibs) +(10) (162,000) +(0.05) (162,000)
Cake Volume = -i (85 Ib/ft3) (0.45)
Cake Volume = 4,870 ft3/cby
381
-------
Calculate volume of sludge per operating cycle assuming an effective
operating time of 20 hrs/day - two hours per cycle.
Cake Volume/Cycle =4,870 ft3/day = 487 ft3/ ,_
10 cycles/day ' Y
Calculate plate requirements assuming 64 inches diameter press
with a capacity of 2.4 fr* per p|aj.e.
Number of Plates = 487 ftVcycle _
2.4ft3/plate
Select two 100 plate presses 64 inches in diameter.
Cost Estimates (Solids Handling)
Item Est. Cost
Earthwork $141,000
Concrete 883,000
Piping and Valves 12,000
Mechanical 268,000
Structures 152,000
Filter Press and Auxiliary Equipment 1,110,000
Installation 186,000
Lime Addition System 72,000
Electrical 10,000
Instrumentation and Control 82,000
Contingencies and Miscellaneous 394,000
Total Capital $3,310,000
Operating Costs $680,000
Fixed Annual Cost 237,000
______^__ $917,000
SUMMARY
The design criteria, design calculations, and unit process cost estimates have
been presented herein. A conceptual layout of the proposed treatment facility
is shown in Figure 163. The summarized unit costs are tabulated in Table 52.
382
-------
CONCEPTUAL LAYOUT OF THE DEEPWATER
REGIONAL TREATMENT FACILITIES
FINAL CLARIFICATION
BASINS,
PRIMARY CLARIFICATION NEUTRALIZATION PREMIXING
BASINS •
BASINS
-'BASIN
k0O
/Q0
00
00
^ 1
PROPERTY BOUNDARY/*1
— |
MASTER
CONTROL
CENTER
PILOT
PLANT
^y
...._/
f
$*
-^
y
/
•\
SCALE I" ' 200'
-------
TABLE 52
COST ESTIMATES FOR THE REGIONAL TREATMENT FACILITY
Construction Annual O&M Total
Item Costs Costs Annual Costs
Description
1 $ 810,000 $165,000 223,000
2 3,090,000 120,000 341,500
3 13,520,000 888,000 1,857,400
4 3,310,000 680,000 917,000
5 912,000 40,000 105,400
6 2,500,000 - 179,200
7 450,000 - 32,400
8 800,000 12,000 69,400
9 1,000,000 - 71,700
r\
Neutralization*
Primary Clarification^
Secondary Biological System
Solids Handling and Disposal3
Electrical and Site Piping4
Foundation Work5
Re-routing of Henby Creek
Outfall Structure
Land Costs
Sob Total $26,392,OOP $1,905,000 $3,797,000
10 13,565,000 1,060,000 2,032,500 Carbon Adsorption Effluent Polishing
Total$39,957,000 $2,965,000 $5,829,500
Costs based on ENR of 1400 and include construction, engineering, legal,
administrative, profit and contingencies. This ENR value used to be
consistent with estimates cited in the Preliminary Engineering Report.
2
Costs include ancillary appurtenances up to process limits.
3
Cost includes sludge handling system - connection and controls.
4.
Electrical and piping costs outside unit process limits.
Additional cost only if extensive pile foundations required.
384
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SECTION VIII
EFFLUENT QUALITY ANALYSIS
The logical outgrowth of the bench and pilot scale treatability studies, the
resulting formation of treatment concept, and the preliminary design of this
system is to predict the quality of the effluent and relate it to the DRBC
effluent quality standards. The activated sludge process followed by effluent
polishing using activated carbon is deemed to be the most applicable system
based on current technology for treating the combined wastewaters to a
quality level commensurate with the DRBC objectives. This is predicated on
the extensive bench and pilot work conducted pursuant to this project and the
accompanying chemical and bio-chemical analyses.
The results of these bench and pilot studies in terms of effluent quality anlayses
from the secondary activated sludge and the carbon column effluent polishing
process are tabulated and summarized herein. They are then discussed inter-
pretively with respect to the effluent quality standards as adopted by the
Delaware River Basin Commission on March 7, 1968 and as amended through
March 26, 1970. The interpretive guidelines adopted by the Commission on
January 26, 1972 are shown in Table 53.
It is recognized that the effluent quality projection presented in this Section is
based on the treatability of the combined wastewaters having the quality characteri-
stics presented in this Report. However, the period of time over which the
treated and untreated wastewaters were characterized affords statistical creditability.
The effluent quality as predicted in this section is therefore sufficiently accurate
to justify implementation of the recommended system Which has the capacity to
treat wastewaters of a similar nature to this quality level.
EFFLEUNT STANDARDS FOR THE REGIONAL TREATMENT FACILITY
The effluent criteria recently established by the DRBC are presented in Table 53.
DISCUSSION OF EFFLUENT QUALITY
The effluent quality as predicted from the bench scale tests is tabulated in Table
54. A more comprehensive quality analysis observed during summer and
385
-------
TABLE 53
EFFLUENT QUALITY REQUIREMENTS
DELAWARE RIVER BASIN COMMISSION
Adopted January 26, 1972
1. Suspended Solids;
For municipal and industrial waste treatment facilities, at least 90 percent removal
as determined by an average of samples taken over each period of 30 consecutive
days of the year and not to exceed 100 mg/l, whichever is less,
2. Public Safety;
A. Temperature - Maximum 110°F where readily accessible to human contact.
3. Limits;
A. Oil - not to exceed 10 mg/l; no readily visible oil.
B. Debris, scum, or other floating materials - none.
C . Toxicity -
1) Not more than 50 percent mortality in 96 hours in an appropriate bioassay
test with a 1:1 dilution. Wastes containing chlorine may be dechlorinated
prior to the bioassay test.
2) Notwithstanding the results of the tests prescribed in the stream quality
objectives, the substances listed below being accumulative or conservative,
shall not exceed the following specified limits in an effluent:
Limit mg/l
Arsenic 0.1
Barium 2.0
Cadimum 0.02
Chromium (hexavalent) 0.10
Copper 0,20
Lead 0.10
Mercury 0.01
Selenium 0.02
Zinc 0.60
3) Persistent pesticides - not to exceed one one-hundredth of the TLcg value
at 96 hours as determined by appropriate bioassay.
D. Odor - not to exceed a threshold number of 250.
E. BOD -
1) The former INCODEL Standards which were saved from repeal by
Resolution 67-7 remain applicable; that is, no discharge shall exceed a
daily average of 50 mg/l in Zone 1 and 100 mg/l in Zone 2. A slight
deviation may be permitted by the Commission when it results from reduced
secondary treatment plant efficiency caused by wastewater temperatures
below 59°F(15°C).
2) In Zones 2, 3, 4, and 5, a waste shall receive not less than zone percent
reduction in addition to meeting allocation requirements.
These guidelines will be administered in accordance with the procedures contained in the
Commission's Basin Regulations-Water Quality adopted 3/7/68.
386
-------
TABLE 54
PREDICTED EFFLUENT QUALITY OF BIOLOGICAL
TREATMENT BASED ON BENCH SCALE TEST*
QUALITY PARAMETER
MEAN VALUES
EFFLUENT RANGE
BOD (filtered)
COD (filtered)
IOC (filtered)
Phenols
MBAS
TKN
N02 + N03-N
Color
Heavy Metals
13 mg/1
90 mg/1
65 mg/1
6-30 mg/1
60-250 mg/1
30-90 mg/1
.01-0.30 mg/1
7**
12-25 mg/1
30-55 mg/1
not measured
not measured
* Represent effluent quality levels using conventional biological
treatment — organic loading 0.5 Ibs BOD/day/lb MLSS. Influent
includes all industrial and municipal participants, proportionate
to flow (Wastewater 510).
** Based on one analysis.
387
-------
winter biological operations of the pilot plant is shown in Table 55. These
data are discussed on a parametric basis. Table 56 presents the effluent
quality of the pilot carbon columns.
Suspended Solids
The effluent suspended solids from the biological pilot plant ranged from 30 to
90 mg/l with a mean value of 52 mg/1. The carbon column effluent varied from
10 to 25 mg/l with a mean of 15 mg/l.
Temperature
The temperature of the effluent from the biological system ranged from approxi-
mately 5°C (41°F) during winter operations to 32°C (89°F) during the summer.
There will be no significant deviation from this range in a full scale plant,
although the winter effluent temperature is expected to be slightly higher based
on heat balance calculations. The temperature of the biologically treated
effluent will not be altered significantly through the polishing carbon columns.
pH_
The influent to the regional plant, as in the pilot plant studies, will be neutra-
lized to a pH in the 7 to 8.5 range. This pH will drop slightly in the secondary
biological plant to a range of 6.5 to 8.0. No significant change in pH was
observed through both the bench and pilot scale carbon columns, and this is expected
to hold true for the full scale facility.
Oil
No oils of any consequence were noted in the composited raw wastewater through-
out the treating program. Even if oils get into the interceptor, the activated
sludge system can reduce oily substances from -50 mg/l to less than 10 mg/l.
This system, coupled with carbon adsorption, should produce an effluent free of
visible oil and less than 5 mg/l total oil.
Debris, Scum, Or Other Floating Materials
This criteria as established by the DRBC can be easily met by the proposed treat-
ment system.
Toxicity
Toxicity tests were completed on the biological and activated carbon column
effluents during the March, 1971 testing period. The toxicity tests were run
388
-------
TABLE 55
Summer Conditions Winter Condition?
PARAMETER
BOD5 (filtered) mg/1
BOD (unfiltered) mg/1
COD (filtered) mg/1
COD (unfiltered) mg/1
TOC (filtered) mg/1
TOC (unfiltered) mg/1
TOD (filtered) mg/1
TOD (unfiltered) mg/1
Mean . Range
11 7-20
13 10-23
113 66-160
169 78-230
39 22-57
43 23-60
113 50-172
116 45-165
Mean Range
60 40-83
78 49-122
248 199-298
324 234-527
77 60-93
84 61-150
233 164-292
251 176-314
Summer & Winter Conditions
Kjeldhal Nitrogen, mg/1
Ammonia Nitrogen, mg/1
N0_ + NO_-N, mg/1
Total P, mg/1
Phenols, mg/1
Color, Standard Units
TSS, mg/1
TDS, mg/1
Sulfates, mg/1
MBAS, mg/1
Fecal Coliforms
Aluminum, mg/1*
Arsenic, mg/1
Cadmium, mg/1
Chromium (total) mg/1*
Chloride, mg/1
Copper, mg/1*
Fluoride, mg/1
Iron, mg/1*
Lead, mg/1*
Manganese, mg/1*
Mercury, mg/1*
Nickel, mg/1*
Silver, mg/1*
StroYitium, mg/1*
Zinc, mg/1*
Mean
24.2
21.4
15.4
0.95
0.75
746
52
1,910
510
3.2
0
0.44
< 0.01
< 0.02
< 0.1
548
< 0.1
0.248
< 0.32
< 0.1
0.65
0.00114
< 0.1
< 0.1
0.41
< 0.63
Ranee
9.5-47.0
8.8-38.0
1.2-58.0
0.1-3.9 '
0.04-8.00
300-1,440
30-90
1,780-2,110
448-575
2.2-4.2
-
0.3-0.7
-
< 0.01-0.03
-
450-620
< 0.1-0.2
0.04-0.54
< 0.1-1.1
< 0.1-0.2
0.2-1.2
0-0.0050
< 0.1-0.2
••
0.3-0.6
< 0.1-1.4
* Sensitivity Limit of Analysis
389
-------
TABLE 56
OBSERVED EFFLUENT QUALITY OF THE PILOT CARBON COLUMNS*
PARAMETER
BOD (filtered) mg/1
BOD- (unfiltered) mg/1
COD (filtered) mg/1
COD (unfiltered) mg/1
TSS, mg/1
Color, Standard Units
Phenols ^ mg/1
MBAS, mg/1
MEAN
20
25
62
94
15
100**
0.09
0.15
RANGE
10-36
17-40
29-102
33-204
10-25
0-100
0.05-0.15
0.05-0.20
* Data generated during winter operations
** Color breakthrough occurred after COD breakthrough, therefore color
during column operation would be <100 color units.
390
-------
in accordance with the procedures described in the FISH-PESTICIDE ACUTE
TOXIC1TY TEST METHOD prepared by the Environmental Protection Agency
and the Fish Bioassay Procedure described in the 1970 edition of Standard
Methods (APH A). ——
The toxiclty tests were made utilising fathead minnows (Pimephales promeias)
acquired from a commercial hatchery in Arkansas and had a mean weight and
length of 0.96 oz. and 37 mm, respectively. . >;
The test fish were observed in the laboratory hatchery facilities for at least
10 days prior to testing. During that period, mortality in the test populations
was less than 2 percent and the fish were judged to be in excellent physical
condition. Bioassays were conducted in five gallon glass vessels held in
constant temperature (18°C + 0.5). water baths. The test diluent consisted of
15 liters of deionized water of at least one million ohms resistivity which was
reconstituted by adding three mg potassium chloride, 30 mg calcium sulfete,
30 mg magnesium sulfate, and 48 mg sodium bicarbonate per liter. The pH
of the diluent was 7.1, and the methyl orange alkalinity was 35 ppm. Bioassays
were conducted under static conditions, without aeration, and with a single
introduction of the effluent in question. Fish of any one species were of
approximately the same weight and length '(+ 20%). Fish were conditioned to
the test water for at least 24 hours prior to testing. Test solutions were pre-
pared by adding appropriate amounts of effluent to sufficient test diluent to
yield a final test volume of 15 liters. The dissolved oxygen levels in the
effluent tested was never less than 5.2 mg/l. The test diluent was saturated
prior to use in a bioassay by bubbling oxygen through it. Ten fish were tested
at each concentration, the mass/volume ratio never exceeded 1.0 gram of
fish per liter of water. A minimum of seven concentrations of the chemical
formulation were prepared in logorithmic series and used to evaluate the
susceptibility of each fish species to each compound.
The 96 hour TLjQ values (95 percent confidence interval) were obtained on the
six hour aeration effluent, the 12 hour aeration effluent and the 12 hour
aeration effluent treated with granular activated carbon. The six hour aeration
effluent TI.50 values at 96 hours averaged 15.9 percent wastewater in the test
solution. The 12 hour aeration effluent TL5Q values at 96 hours averaged 30.0
percent wastewater in the test solution. The activated carbon effluents showed
no toxic effects at 96 hours and therefore, since all the fish were alive after
96 hours, no ll^Q values were obtained. Hence the effluent from the carbon
columns will meet or exceed the effluent quality as set forth in Table 54.
Odor
Odor tests were completed on the biological and carbon effluents during the
391
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March, 1971 testing period. The threshold odor numbers for the biological
effluent ranged from 200 to 800, with a geometric mean of 346. In comparison,
the carbon effluent threshold odor number was four based on a 24 hour composite
sample.
BOD
Extensive effluent BO05 information is available from these bench and pilot
scale treatability studies. As noted in Tables 54 and 55, the BO05 of the
biologically treated effluent can be expected to range from 7 to 30 mg/l during
summer operations and as high as 122 mg/l during the most severe winter conditions.
If carbon adsorption is used as an effluent polishing step, this can be reduced to
a BO05 concentration of less than approximately 25 mg/l throughout the operating
year.
During the course of this investigation, a series of BOD analyses were run in order
to tabulate biochemical oxygen demand versus time. The objectives of obtaining
this information were (1) to determine first-stage biochemical oxygen demand
reaction rate K, (2) to determine first stage ultimate oxygen demands, and
(3) to use the information thus obtained to predict first stage ultimate oxygen
demands (FSOD). i
In order to accomplish the above objectives, BOD data obtained during the
months of February and March, 1971, were analyzed by several techniques.
Both the rapid ratio method and the method of moments were used to ascertain
first stage BOD reaction rates and first stage ultimate oxygen demands.
Additionally, k rates developed from this winter operations data were compared
for similarity with data obtained during previous summer operations.
The BOD data used for this study are tabulated in Table 56. It should be noted
that BOD's were taken at intervals of 1, 3, 5,7, 11, 15 and 20 days, thus
allowing a BOD vs time relationship to be developed. All samples used were
inhibited against nitrification. Therefore, the first stage biochemical oxygen
demand being measured should have approached the first order reaction
mathematically described by Equation VII1-1.
y = L(l-10-kt) Vlll-l
where:
y = biochemical oxygen demand exerted at time t
L = first stage ultimate oxygen demand
k = reaction rate constant
t = time
392
-------
Analyzing the data using the two techniques mentioned in the preceding, the
following results were obtained:
1 . Using the rapid ratio method —
(avg) =0.059 day-*, L = 214 mg/l
2. Using the method of moments -
kj (avg) = 0.080 day'l , L = 214 mg/l
3. Using the average of the above two determined values -
kl (avg) = 0.070 day-1, L = 214 mg/l
The average rate constant as determined above compared favorably with rate
constants developed from BOD data obtained during operations during the
summer of 1970. It was therefore possible to use the rate constants developed
to determine FSOD (first stage oxygen demands) for winter and summer operations
assuming an average BOD5 of 20 mg/l . This was done by means of the following
calculation and yielded an average FSOD of 36.2 mg/l .
since y = L(l-10~kt)
20 = L(l-10-5k)
and
Using the average kj value of 0.070 day
This therefore indicates that during summer operations if effluent five-day BOD's
are maintained at 20 mg/l, the FSOD should not exceed 36 mg/l on the average.
This predicted value compares quite favorably with measured BOD2Q values of
from 25 to 30 mg/l during summer operations. This is a conservative approach
in that k values tend to decrease with an increasing degree of biological treat-
ment. This means that when the effluent is of better BOD quality than that
reported in Table 55, FSOD/BOD5 ratio will tend to decrease toward unity.
The FSOD for winter operations can be calculated in the following manner. The
k value of 0.070 day"' is referenced to the standard incubation temperature of
20°C and therefore can be used to correct five day BOD values to FSOD levels
at any temperature. Assuming the BODs of the biological treated effluent during
winter operations ranges between 49 and 122 mg/l, an FSOD range between 90 and
220 mg/l could be expected .
393
-------
As previously stated, the biological system followed by a polishing step using
carbon columns is capable of producing an effluent having a BOD5 of less
than 15 mg/l during summer operations. This level is not expected to materially
increase during the winter months because carbon capacity is available to
handle the increased organic loading to the columns. On this basis, the final
effluent FSOD can be expected to range between 10 to 35 mg/l throughout the
year.
••?
Color
Color levels of the biological and carbon effluents were measured on the
platinum-cobalt scale. The effluent color from the biological system is included
in Table 55. The mean value of 746 units exceeds regulatory criteria. Excellent
color removal was effected, however, in the bench and pilot scale carbon columns
as indicated in Section VI. Based on these data, the color of the carbon column
effluent will be below 100 standard units on the platinum-cobalt scale.
Trace Organ!cs
Phenols were monitored through both the biological system and the carbon
columns. Phenols and organic compounds exhibiting "phenolic" characteristics
are both biodegradable and sorbable. This is confirmed by the phenol carbon
isotherms shown in Section V, the bench scale carbon studies shown in
Section VI, Figure 127, and the biological removal indicated in Table 55.
Based on this data, the biologically treated effluent will have a phenol con-
centration in the 0.04 to 8.00 mg/l range and the phenols will be less than
.05 mg/l in the carbon column effluent.
Many of the miscellaneous trace organics will be removed to levels below
detection limits in the carbon columns, with the exception of refractory
compounds. There is nothing to indicate, however, that these refractions will
cause any deleterious effect on the water body receiving the treated effluent.
Inorganic Constituents
Little change in the level of dissolved inorganic constituents through the
bio logical-carbon system can be anticipated. Based on the composite waste-
waters used in this study, the effluent from the biological and carbon units
will contain a TDS of 1700 to 2200 mg/l, fluorides of <1.0 mg/l, chlorides of
400 to 650 mg/l, sulfates of 400 to 600 mg/l, and nutrites-nitrates of 1 to
60 mg/l. These concentrations in the biologically treated effluent are reported
in Table 55.
394
-------
Nutrient^
The nitrogen and phosphorus levels in the biologically treated effluent are shown
in Table 27. These are reported in terms of TKN (ammonia and organic N)
with a mean value of 24 mg/l; ammonia-nitrogen, which has a mean level of
21 mg/l; and total phosphorus, which has a mean level of 1.0 mg/l. Based on the
ammonia analyses through the biological plant, little nitrification occurred within
the 12 hour detention time. This indicates that biological effluent ammonia will
be highly dependent on the influent concentration. Moreover, no significant
degree of ammonia removal can be expected through the carbon columns as
indicated in Section VI. The phosphate concentration will remain relatively
unchanged through the carbon columns.
Fecal Coliforms
No fecal col i forms were observed in the effluent from the pilot plant at any
time during the study as shown in Table 55.
Heavy Metals
Heavy metallic ions were analyzed using an atomic adsorption spectrophotometer
through the pilot plant treatabilitity studies. The average values for 12 different
metals in the biologically treated effluent are listed in Table 55. The levels
indicated therein are commensurate with the accuracy of the analytical equipment
used to perform those analyses. It is noted that the most sensitive analytical
capability was for mercury, where levels as low as one part per billion could
be detected.
Only a slight decrease in metallic ion concentration can be anticipated in the
effluent polishing step based on observed data. This slight removal is most
probably attributable to sorption of organic-metal lie complexes, or organic
compounds with metallic functional groups.
Radioactivity
The level of radioactive substances in the biological and carbon effluents were
analyzed. Both gamma and gross beta radiation levels were determined. The
gamma radiation activity (photons originating from nuclei! of excited atoms) is
indicated m Table 57. Gross beta levels (negation of nuclear origin) are pre-
sented in Table 58. The radioactivity indicated represent normal levels well
below hazardous thresholds. It is interesting to note the removal of both beta
and gamma emitting substances in the carbon column.
395
-------
TABLE 57
GROSS GAMMA ANALYSES (0-2.56 MeV)
Sample Description Al A2
Suspended
Bl
B2
Al
Dissolved
A2 Bl
B2
Weight kg
.648
654
667
612
nCi/kg
(Kr4Q equivalent) neg neg 0.15 (±11) 0.3 (±12) 2.7 (±1) 1.2 (±1) neg 0.5 (±1)
nCi/kg
CY equivalent! neg neg 0.2 C±.01) .01 (±.01) 0.2 (±1) 0.1 (±1) neg 0.06 (±.1)
No spectral peaks were observed except for K-40 in A dissolved.
"A" Samples • Biologically treated effluent
"B" Samples * Carbon column effluent
-------
TABLE 58
GROSS BETA ANALYSES
Gross g"
20 ml sample volumes evaporated on stainless steel planchets and
counted on Nuclear Chicago Low Background proportional-counter.
Sample # Activity pCi/1
A-l 28.4 ± 6.1
20.3
A-2 12.2 ± 5.8
B-l 13.5 ± 5.8
15.8
B-2 18.0 ± 5.9
Lower limits of detection: x * -025 B " '05°
MSMA - 7.65 pCi/1
MDTA • 14.07 pCi/1
"A" Samples - Biologically treated effluent
"B" Samples - Carbon column effluent
397
-------
SUMMARY
The predicted effluent quality from both the biological treatment facility and
the carbon columns have been discussed in this Section. These values, which
correspond to the quality of the composited raw wastewater used in this testing
program and the stated treatment conditions/ are tabulated in Table 59.
398
-------
TABLK 59
PREDICTED EFFLUENT QUALITY
Constituent
BOD5, mg/1
FSOD, mg/1
COD, mg/1
V
PH
temperature, C
TSS, mg/1
TDS, mg/1
Toxicity (Bioassays TL,-
@ 96 hr)i(% wastewater)
Oil
Color, standard units
Odor
MBAS, mg/1
Phenols , mg/1
Chloride, mg/1
Fluoride, mg/1
NH3-N, mg/1
TKN-N, mg/1
Total P, mg/1
Primary Effluent
150-340
-
400-800
7-8.5
7-33
20-40
1,780-2,200
-
10-20
300-1,440
-
2.2-4.2
0.5-15
400-650
< I
8.8-38
9.5-47
0.1-3.9
Activated Sludge
Effluent
7-122
12-220
80-230
6.5-8
5-32
20-50
1,780-2,200
30%
< 10
300-1,440
200-800
2.2-4.2
0.05-10
400-650
< 1
8.8-38
9.5-47
0.1-3.9
Combined Activated Sludge-
Carbon Effluent
< 20
10-35
< 80
6.5-8
No significant removal
10-25
No significant removal
100%
< 5
< 100
=4.0
< .40
< 0.05
No significant removal
< 1
No significant removal'
No significant removal
No significant removal
Remarks
BOD residual depends on BOD/COO
ratio which characterizes rela-
tive biodegradability of wastewater
Exact COD residuals vary with
complexity of wastewater & design
contact times in the Act. S. and
Carbon Treatment Plants.
pH drop in Act. S. systems at-
tributed to biological production
of CO and intermediate acids. pH
change in carbon columns depends
on preferential adsorption of
acidic and basic organics.
TDS is essentially unchanged
through all three treatment systems .
Phenols (ice) are generally amenable
to biological and sorption removal.
-------
TABU 59 cont'd.
PREDICTED EFFLUENT QUALITY
Constituent
Fecal Coliforms
Radioactive Substances
Gamma pCi/kg
Beta pCi/1
Heavy Metals
Aluminum, mg/1
Arsenic, mg/1
Cadmium, mg/1
Chromium (Total) , mg/1
• Copper, mg/1
Iron, mg/1
Lead, mg/1
Manganese, mg/1
Mercury, mg/1
Nickel, mg/1
Silver, mg/1
Strontium, mg/1
Zinc, mg/1
Primary Effluent
0
-
0.3-0.7
< 0.01
< 0.02
< 0.1
< 0.1-0.2
< 0.1-1.1
< 0.1-0.2
0.2-1.2
0-0.0050
< 0.1-0. 2
< O.I
0.3-0.6
< 0.1-1.4
Activated Sludge
Effluent
0
0.1-0.2
20.5
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
No significant removal
Combined Activated Sludge Remarks
Carbon Effluent
<
0
0-0.6
15^8
Values reported are based on anal-
ysis as shown in Figure VI-2.
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight -removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
Possibility of slight removal
-------
APPEND IX A
STATPK COMPUTER PROGRAM
ELECTRONIC DATA ANALYSIS AND PROCESSING
The large quantity of data accumulated during this extensive wastewater
characterization and biological waste treatment investigation makes rapid
and reliable data handling and analysis techniques indispensable. It is
valuable for the user of these data to know the statistical reliability of his
information. The development of the design parameters and coefficients for
biological waste treatment processes involves numerous mathematical mani-
pulations which are both time-consuming and subject to computational error.
It is also informative to determine the error inherent in the design coefficients
and-parameters to reduce the uncertainty in process design calculations.
Unfortunately, application of the theory of propagation of errors to field data
is a time-consuming process and is thus usually neglected in biological waste
treatment investigations.
The availability and utility of high-speed electronic computers gives the
environmental engineer a tool which he can use to relieve himself of tedious
and complicated mathematical procedures. In view of the myriad of data
accumulated during the bench and pilot scale phases of this project, a computer
program was developed to perform the necessary mathematical operations on
biological waste treatment process information and to arrive at the required
design information and the errors associated with it. This program provides the
user with the following analyses:
1. Analysis of user-selected parameters to determine if steady-state conditions
prevailed during the sampling period.
2. A statistical analysis of each parameter for the sampling period.
3. Removal of outliers from the original data (for each parameter) and a
recompuration of the statistics.
4. Computation of biological waste treatment process parameters (organic
loading, removal rates, etc.) and their associated most probable errors.
5. Least squares curve fitting of process parameters to obtain design coefficients
(a, a1, b, b1). Correlation coefficients are developed to indicate the error
401
-------
in these coefficients.
6. Plotting graphically either with a pen plotter or line printer/ the design
parameters and coefficients previously computed.
The computer program was developed for use on a high-speed, large core computer
such as the UNIVAC 1108, CDC 6400, or IBM 360/50. With the exception of the
plotting routines, the program is machine independent. Most of the typical data
analysis problems solved with this program should compile and execute in consi-
derably under one minute on any of the above machines. This results in a consi-
derable savings in manpower as well as permitting a better statistical analysis with
a reduced opportunity for error.
The following paragraphs briefly consider each of the aforementioned analyses
performed by Program STATPK which is schematically illustrated in Figure A-T.
The reader is referred to the bibliography and user's manual if additional Informa-
tion on the computational algorithm is desired (References 1, 2, and 3).
Data Input
Program STATPK is user-oriented and is thus relatively simple for an individual
to use with only a basic knowledge of computers and FORTRAN. The input
data are written on specially designed coding forms to facilitate coding and
keypunching. A maximum of 32 different input parameters, not including the
date of sampling, are used in this program. These parameters are:
Influent*
Total
Total COD
Total TOD
Total TOC
Soluble BODs
Soluble COD
Soluble TOD
Soluble TOC
TSS
VSS
IOD
Effluent*
Total BOD5
Total COD
Total TOD
Total TOC
Settled BOD5
Settled COD
Settled TOD
Settled TOC
Soluble BOD5
Soluble COD
Soluble TOD
Soluble TOC
TSS
VSS
Mixed Liquor
Waste Flow Rate (liters/day)
Aeration Volume (liters)
TSS*
VSS*
Oxygen uptake (mg/l/hr)
Temperature (°C) c
Waste Solids (gms/day)
mg/l unless otherwise indicated
402
-------
Figure A-l
SCHEMATIC OF COMPUTATIONAL
TECHNIQUE PROGRAM STATPK
REMOVE
OUTLIERS IN
EACH PARAMETER
SET
ARE
BIOLOGICAL
DESIGN COEFFICIENTS
DESIRED
READ DATA
FOR CURVE
FITTING AND
PLOTTING
LEAST SQUARES
CURVE FITTING
OF SELECTED
PARAMETERS
READ
UNIT
OPERATIONS
DATA
COMPARE ORIGINAL
IS CHECK
FOR STEADY-STATE
CONDITIONS
DESIRED
WRITE RESULTS
OF STATISTICAL
ANALYSIS
IS
PEN PLOTTER
PLOT DESIRED?
LINEAR TRE
ANALYSIS OF
SELECTED
PARAMETERS
HAVE
ALL DATA SETS
BEEN READ?
WRITE RESULTS
OF STEADY-STATE
ANALYSIS
PEN PLOTTER
PLOT OF BIOL.
DESIGN CURVES
LINE PRINTER
PLOT OF BIOL.
DESIGN CURVE
ARE
BIOLOGICAL WASTE
TREATMENT PARAMS
DESIRED?
STATISTICAL
ANALYSIS
OF ALL
PARAMETERS
TERMINATE
EXECUTION
COMPUTE BIOLOGICAL
WASTE TREATMENT
PARAMETERS AND THE
ASSOCIATED MOST
PROBABLE ERRORS
IS
OUTLIER REMOVAL
DESIRED
ITE PARAMETERS
AND MOST PROBABLE
E
403
-------
Any or all of the above parameters are entered on a coding form for each
sampling period. If a parameter is not sampled or is not to be included in the
computations, a negative one is entered in its position on the appropriate coding
form. This is necessary since the program would otherwise use a zero value in the
statistical computations. Three coding forms, designated Files 1,2, and 3, are
filled out for each sample period. A "data set" is formed from a number of sample
periods representing biological waste treatment process operation for one set of
steady-state conditions. A "data set" will result in one set of design parameters
(organic loadings, removal velocities, etc.). Three or more" "data sets" are
required for computation of the biological design coefficients (a, a1, b, b1)
since each set produces one point!for the least squares curve-fitting technique.
Although the program would fit a curve through two points (two data sets),
this practice should be considered undesirable because of the uncertainty inherent
with the limited amount of data used.
The user reads in a number of these data sets, each separated by an end-of-file
card, for a computational run* The last data set to be read is followed by an
end-of-job card which indicates the end of the problem to the computer.
Steady-State Analysis
The theory behind the calculation of the biological waste treatment process
design parameters and coefficients assumes that steady-state (with respect to
time) conditions prevailed when the process data were taken. Since this assumption
is fundamental to the development of these coefficients, it is advisable to
determine, if possible, the existence of time-dependent trends in a data set.
The user of this program selects anywhere from one to four input (process)
parameters which he feels would be most likely to show the presence or absence
of steady-state conditions (e.g. , effluent total COD, MLVSS, etc.). It is
also desirable to use essentially equally-spaced data with as many samples as
possible. These conditions assure maximum reliability of the curve-fitting
process used in the trend analysis.
The parameters to be analyzed for trends are treated as the dependent variable with,
time being treated as the independent variable, giving an equation of the form:
y = a + bt (A-l)
where: y = parameter of interest
t = incremental sample time, t = 0 for the first sample
a, b = regression coefficients
404
-------
X
Least squares regression is used to fit this simple linear function to the data.
The coefficient "b" represents the slope, which defines the time-dependent
trend. A positive slope indicates that the parameter value was increasing
with time while a negative slope denotes the opposite condition. Obviously,
this provides the engineer with a reasonable assessment of the stability of the
process during the sampling period .
However, merely fitting a linear function to the time series data to discern trends
does not provide the analyst with information pertaining to the reliability of the
trend analysis. Thus it is necessary to incorporate a technique to evaluate the
significance and reliability of the trend coefficient (slope). The method used in
this program for this purpose involves the computation of a "t-value1' for the
regression coefficient which is a means for arriving at the confidence intervals of
the coefficient. The equation for computing the t-value of the r«nw»««»on coefficient
is:
t = (b-B) (n-2) Z(x\ -xj2
-Yj')2
-------
The utility of this technique for steady state analysis is obvious. By
specifying appropriate parameters for analysis, the engineer can rapidly and
reliably detect any time dependent trends by this program and a table of
"Student's t" distribution. The program user is referred to any standard
statistics text for additional information on this analysis.
Statistical Analysis
Program STATPK performs a complete statistical analysis on all process
parameters read as input. The statistical analyses used are based upon the
theories of random sampling and small sample distributions, which are also
applicable to large sample sizes. In order to simplify computational procedures
the collected data are assumed to follow a normal Gaussian distribution. With
the exception of parameters which may frequently have values close to or equal
to zero, this assumption should be generally adequate for biological waste
treatment data. The user should be aware that the normality assumption is liable
to fail under certain conditions and should use reasonable care and judgment in
the application of this data analysis package.
The statistical characteristics computed for each parameter are the mean:
n
* * I x. (A-3)
n
where: x = mean of parameter x (estimated)
xj = ith datum of parameter x
n = number of samples;
the standard deviation:
n - 1 (A-4)
where: a - standard deviation of parameter , x
the coefficient of variation:
CV= £ * 100 (A-5)
x
where: CV= coefficient of variation, in percent, and the standard deviation
of the mean:
n (A-6)
406
-------
The four preceding statistical measurements provide the program user with a
guantitative estimate of the validity of the process data. The arithmetic mean,
x, of a series of samples of a given parameter is the most probable value of that
parameter.. It can be shown that the arithmetic mean is the best unbiased estimate
for the true mean of a normally distributed population. The mean also is generally
superior to the mode and median as a measure of central tendency for other types
of distributions because it usually tends to be more stable than these other measures
of location. * -
The standard deviation, a, is a measure of variation or dispersion in a sample
population of a parameter. Standard deviation is a measure of the probability
that a single reading will be near the sample mean value. For most common types
of data, the standard deviation is superior to other common measures of variation
due to its greater stability in repeated sampling experiments, which is similar to
the situation of the mean with respect to other measures of location.
The coefficient of variation, CV, provides the analyst with a measure of a
relationship of the variation in a sample population (a) to the magnitude of the
numbers observed (x~) • This measure indicates whether an increase in variation
(ff) is due to large magnitudes of the parameter being sampled or to some other
influence, such as sampling error. It is also useful in comparing the variability of
parameters which are measured in different units. However, the coefficient of
variation is not a rigorous statistical measure and should not be used to attempt to
quantify the sizes of variations between sample populations of parameters.
The final statistical measure computed by this program is the standard deviation of
the mean,0* . As was previously discussed, the standard deviation, cr, is a
measure of rfie reliability of a single sample with respect to the mean of the sample
population. The standard deviation of the mean is a measure of the reliability
of the estimated mean, x, as a predictor of the true population mean,/*, the
basis for this statistic is that the mean of "n" equally precise observations is a
mujch more reliable estimate of the population mean than any single observation.
The standard deviation of the mean is also useful in estimating probable errors of
products and quotients involving means of various parameters and data sets.
All of the above statistics are computed for each parameter in each data set.
After the statistics are computed, each parameter sample population is searched for
"outliers." Outliers are defined as sample values for which the probability of
occurrence is so low that these values can be considered to be in •rrors and can
thus be discarded from the sample population. An arbitrary cutoff limit of 1.96
standard deviations is used in this program for outlier reduction. This value
corresponds to the 95 percent confidence interval fora Gaussian distribution. By
using 2.58 standard deviations for the cutoff criterion, the analyst could increase
this certainty to 99 percent. The search for outliers in each parameter sample
407
-------
population is conducted using the mean and standard deviation computed for
that population. A new set of statistics is then computed for the modified (out-
liers removed) sample population of each parameter. If a parameter set is found
to have no outliers, this operation is bypassed.
It is mandatory that the modified sample population be representative of the
"true" population of the parameter being considered if meaningful results are
to be obtained in subsequent calculations. To ascertain whether or not the
modified parameter data are still representative of the original sample population,
a form of "Student's t" test is used to compare the means of the two data sets
(original and modified). This test requires an assumption that the variances of
the two populations are equal and tests the hypothesis:
against the alternate:
Hi ' "* * %
where: ;ux and /4y denote the "true" means of the original and modified sample
populations, respectively. The t-value is then computed using the equation:
(x--y)-Q.x->y) /nx 0/^-2) ^
y/nA'+V/ V nfcfy
where:
*• .,
x = estimated mean of original sample population
y = estimated mean of modified sample population
, u= true parameter population means (unknown)
$x= estimated standard deviation of original sample population
S = estimated standard deviation of modified sample population
y
nx= no. of son pies used to estimate x, S
n»= no. of samples used to estimate y",
x
which can be shown to have "Student's t" distribution with "n + n - 2" degrees
of freedom. The computed t-value is tested in a manner similar to that previously
shown for the regression coefficient in the trend analysis. If the alternative
hypothesis CMX rpy) is shown to be valid, the modified data set cannot be used
for any additional calculations since it is not representative of the sample popu-
lation. .In this case, the original sample data are used in the computation of
biological design parameters. If the modified data set passes the t-Test, it is
408
-------
used for these calculations rather than the original data. The removal of
outliers is performed to attempt to eliminate bias in the data due to experimental
Or sampling error.
At this point in the data manipulations, the program now has a mean, standard
deviation, coefficient of variation and standard deviation of the mean for each
parameter in each data set. The statistics may be either from the intitial sample
populations or the sample populations with the outliers removed. The data used
are appropriately flagged to indicate: a) no outliers present and original data
used, b) outliers present and modified data used, and c) outliers present but
original data used due to significant changes in the modified data. These
statistics are then used throughout the remainder of the program to represent each
parameter in all subsequent computations.
. Compute Biological Waste Treatment Design Parameters
The user of program STATPK has the option to calculate a number of biological
waste treatment process parameters for use in process evaluation and design
(Reference 4). These parameters are listed in Table A-J .All computations
leading to these parameters are performed in accordance with established
engineering practice. Each data set provides one (1) value for each of the
design parameters and these values are combined with similar values from other
data sets to compute the biological design coefficients, which will be subsequently
discussed.
It is informative to know the reliability (or uncertainty) of each of the biological
design parameters computed by the program (e.g., Table Anl). The theory of pro-
pagation of errors must be used to develop this information. These design para-
meters are computed by various mathematical manipulations involving addition,
subtraction, multiplication, and division. Since the statistical information for
each of the components entering into the calculation of these design parameters
was previously calculated, it is possible to apply appropriate techniques to esti-
mate the uncertainty in the latter. A measure of this uncertainty is the probable
uncertainty, or error. This statistic assumes that the directly measured quantities
(input parameters) will differ from their true values by amounts less than their
maximum uncertainties (as represented by the standard deviation of the mean),
and that some of the measured values will be larger than their true values while
others will be smaller. The probable uncertainty is computed with the equation:
a .(_A-jt_f _^ + (~n~L * +'"+
xl
409
-------
Influent Parametric
Relationships
Total: BOD5/COD
Soluble: BOD5/COD
Total: BOD5/TOC
Soluble: BOD5/TOC
Total:. BOD5/TOD
Soluble: BOD /TOD
Total: COD/TOC
Soluble: COD/TOC
TABLE A-l
PARAMETERS USED IN PROCESS DESIGN
Removal
Efficiencies
s«-so
C-2— x 100)
o
Total BOD-
Settled BOD-
Soluble BOD,
Total COD
Settled COD
Soluble COD
Total TOD
Settled TOD
Soluble TOD
Total TOC
Settled TOC
Soluble TOC
Design
Parameters
Removal
Velocities
.8 -S N
( o e)
X t
a
Organic Lo
S
o
X t
a
Sludge Age
Respiration -
X
a
AX
Detention Time
Soluble BOD.
Soluble COD
Soluble TOD
Soluble TOC
Soluble BODt
Soluble COD
Soluble TOD
Soluble TOC
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where:
°"~ = probable uncertainty of design parameter
y * design parameter f(x], x2,..., x )
xl/ X2* •••» xn = directly measured input parameters
axi' axo ' * * *' ^x" = standard deviation of the mean for input parameters
The above equation indicates that the error in the computed design parameter
is not directly influenced by the nature of the equation used to calculate it,
but rather is a function of the errors in the independent variables as modified
or propagated by the equation. Any input parameter with a standard deviation
of the mean of zero does not contribute to the error in the design parameter in
any way. Thus, the uncertainty in the design parameter is a function of the
"weakest link" or "links" as the case may be.
After the probable uncertainty is computed for each design parameter in each
of the data sets, all of this information is printed out in a readily usable format.
Selected design parameters are used later in the program computational scheme
to compute design coefficients which are useful in the development of a biological
waste treatment process design.
Design Coefficients
Certain biological waste treatment design coefficients useful in computing
sludge growth rates, process oxygen requirements, and organic removal rates
must be calculated by fitting linear relationships to design parameters measured
at several organic loadings (food to micro-organism ratios). Program STATPK
provides the user with the option to compute these coefficients directly if the
appropriate data are available. Figure A-2 illustrates the relationships
developed in this program and the design coefficients which are calculated
from these relationships . These coefficients are computed for each of the types
of organic parameters in the original data set (e.g., BOD5, COD, TOC, TOD),
as applicable.
It is inadvisable to use this curve-fitting technique if only two sets of data are
available, and obviously it is meaningless for data from only one loading. As
mentioned above, a linear relationship is assumed for design coefficient cal-
culation which is consistent with their theoretical development .
The technique used for estimating the regression coefficients of the assumed
linear relationship is the method of least squares. The appropriate intercepts
and slopes which represent the biological design coefficients are the results of
these regression analyses .
411
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Figure A-2
RELATIONSHIPS FOR DETERMINING DESIGN COEFFICIENTS
REMOVAL
VELOCITY
VSe
y
Sr
' "< VV
EFFLUENT ORGANICS
Se
(a) SUBSTRATE REMOVAL
UNIT
OXYGEN
UPTAKE
RATE
REMOVAL VELOCITY
YSe
(b) OXYGEN UTILIZATION
UNIT
SLUDGE
GROWTH
RATE
AX
REMOVAL VELOCITY
se
REMOVAL
OF
ORGANICS
ORGANIC LOADING
So
o
(c) SLUDGE PRODUCTION
(d) ORGANIC REMOVAL EFFICIENCY
412
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Several statistical parameters are computed to indicate the goodness of fit or
reliability of each regression line. This information includes the sum of the
squares, the correlation coefficient and the index of correlation. The sum of
the squares is obtained directly from the least squares analysis and represents
the minimized residuals between the measured parameter values and the fitted
line. The correlation coefficient is simply a measure of correlation between
the two variables being analyzed and is not a measure of the goodness of fit
of the regression line. However, it is useful in determining the confidence in
the design coefficients obtained from the regression analysis. The correlation
coefficient is calculated from the equation:
n
£ (x. - x ) (y. - y )
(A-9)
nSxSy
where:
r = correlation coefficient
Xj— ith value of design parameter used as independent variable
y. = ith value of design parameter used as dependent variable
x, y = means
S^S = standard deviations
n = number of observations
Correlation coefficients are limited to the range:
1.0 > r > -1.0
Negative correlation coefficients denote an inverse relationship between the
variables. Coefficients with an absolute value of 0.9 or greater demonstrate
a strong relationship between variables and would indicate that curve fitting
should be quite successful. Conversely, correlation coefficients with absolute
values less than 0.7 indicate that the relationship between the variables is very
weak and that curve fitting would likely be unsuccessful.
The index of correlation is a measure of the accuracy of fit of an equation to a
set of experimental data. This statistic is a function of the standard deviation of
the data with respect to the fitted curve and of the apparent standard deviation
of the daw with respect to their mean value. The index of correlation is
computed as:
413
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1 =
where:
I = index of correlation
y. = measured irh value of dependent variable @ x = x.
y = computed value of dependent variable @ x = Xj
y = mean of dependent variable
n = number of observations
Values of I range from 0 to 1.0. A regression equation is considered to fit
the measured data well if the index of correlation lies between 0.94 and 1.0.
Lesser values of this index indicate a poorer fit and thus reduce the reliability
of the design coefficients obtained from the regression analysis.
These measures of goodness of fit are computed for each of the relationships
shown in Figure A-2. Applying these criteria with engineering judgment
permits an evaluation of the reliability of the biological design coefficients.
In addition, the use of the method of least squares to fit the linear relationships
assures that the most reliable fit of the experimental data has been obtained,
regardless of the degree of correlation of the data.
Information Display
All of the input data, the design parameters and their associated statistics are
printed in a readily usable tabular format. This listing is designed so that it
can fit into a standard three-ring notebook. The linear relationships used to
calculate the biological waste treatment process design coefficients are
plotted graphically. The design coefficients themselves and the good ness-of-fit
measures are printed out in a tabular format. The program user has an option in
regard to the type of graphical display he uses to plot the linear relationships.
One option is to use a drum-type pen plotter to graph each of the relationships.
This plotter is found as a peripheral unit of many high-speed computers. The
plot routine in this program is machine-dependent and will operate only on the
Univac 1108 Computer. The pen plots from this option was suitable for direct
inclusion in engineering reports. They include titles, labeled axes, the linear
414
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relationships and the measured data points. A complete graphical plot of the type
shown in Figure A-2 can be completed in approximately seven minutes with the
Univac plotting system.
The other plotting option is executed on the standard line printer and is commonly
known as a "printer plot." Standard printer characters are used to generate the
plot which includes labeled axes, titles, the regression line and the measured
data for each relationship. The relationship can be traced directly from the
printer plot to standard paper and can be used in a report with appropriate labeling
lettered in. Each of the design relationships shown in Figure A-2 may be plotted
in this manner.
Caveat
Program STATPK is a powerful tool for analyzing experimental biological waste
treatment process data and as such it should be used with care and judgment.
The design parameters and coefficients calculated by this program are no better
than the input data and should be considered in this context.
Particular care should be taken in the interpretation of the statistical analyses.
As was previously discussed, most of these analyses assume that the data are taken
from a normal (Gaussian) distribution. Slight deviations from this distribution
type will cause no problems, but serious discrepancies can arise if unusual
population distributions exist. An example of this is an industrial waste which is
subject to large dumps and spills and which is in fact a combination of several
different populations. The normality assumption will fail completely in this
case and the computed statistical measures will be meaningless. The user of the
program should be aware of the characteristics of the waste and process being
analyzed so that he can find any ambiguties in the input data. If a discrepancy
in the statistical analysis is suspected, it is wise to graphically display the pro-
bability distribution of the suspect parameter on probability graph paper so that
it may be closely examined to verify or reject the normality assumption.
The other assumptions made in the statistical analyses, such as the assumption of
equality of variances for the t-Test, should also be considered when using the
results of the program. In conclusion, this program uses the best data analysis
techniques available for its purpose, but none are universally applicable. In the
final analysis, only sound engineering judgment can provide the desired confidence
in the final design.
Summary
This section has included a brief description of the STATPK program which was used
to resolve the pilot plant data into the necessary design parameters, coefficients,
415
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and constants with the corresponding statistical accuracy. Although the Program
was developed specifically for the Deepwater Pilot Plant Study because of the
myriad of data accumulated, it will have application for similar projects requiring
biological process kinetics and coefficient derivation.
416
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REFERENCES — APPENDIX A
1. Fogel, C. M., Introduction to Engineering Computations, International
Textbook Co., Scrgjvtbn, Pennsylvania (1960).
2. Sterling, T. D. and Pollack, S. V., Introduction to Statistical Data
Processing, Prentice-Hall, Englewood Cliffs, New Jersey (1968).
3. Hoel, P. G., Introduction to Mathematical Statistics, 3rd edition,
John Wiley and Sons, Inc., New York (1962).
4. Eckenfelder, W. W., Jr., Industrial Water Pollution Control, McGraw-
Hill, New York (1966).
417
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SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
3. Accession No,.
w
4, Title
FINAL REPORT -DEEPWATER PILOT PLANT TREATABILITY STUDY I]
". Atsthor(s)
[10. Project No,
9 DELAWARE RIVER BASIN COMMISSION, TRENTON, NEW JERSEY
ENGINEERING-SCIENCE, INC., WASHINGTON, D.C.
IS. Su vj'liar.eatary Notes
Environmental Protection Agen9y report number,
EPA-660/2-73-038, March 1974.
11. Contract/Grant No.
EPA PROJECT 11060-DRtf
16. Abstract
The Delaware River Basin Commission initiated a study of a joint industrial-municipal
regional wastewater collection and treatment system for southern New Jersey. Staff personnel
determined an optimum collection area for ten industrial plants and inclusive municipalities.
Engineering-Science, Inc. was selected as design and operating engineers of a 50 gpm
pilot plant to treat a composite of refinery, petrochemical, and municipal wastewater.
Raw wastewater was subjected to the following processes: pretreatment, equalization,
neutralization, primary clarification, varied types of activated sludge, final clarification,
and intermittent varied testing on polishing and disinfection.
The activated sludge process, at optimum conditions, removed 90 percent of the
BOD of the strong predominately industrial waste. The raw wastewater color ranged from 200
to 1800 units color which was readily removed by carbon sorption of the activated sludge
effluent.
Aerobic digestion reduced excess activated sludge volatile suspended solids 50 percent
in 20 days. Either vacuum filtration or filter pressing would be most applicable for dewatering.
Pilot plant operation confirmed treatability proposals, developed design criteria and
pointed out areas of concern for additional study.
17a. Descriptors
*P5lot Plants, *Activated Sludge, * Regional Analysis
Activated Carbon, Organic Loading, Delaware River Basin Commission
17 b. Identifiers
*Proposed industrial-municipal regional wastewater treatment, New Jersey
17c. COWRk field & Group 05D
•^••HB^^MMM^MM^MMIMMi
18. Availability Send To:
WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON, D. C. 2O24O
^g^^^g^gg^^^p^^p^pj^^^^^^^^^^^^^^^^^^^^^^^UiMyiiHBHMttlltidildUMkiVMVVHialMMI^
actor Webber-Delaware River Basin Cbmm.)
U.S. GOVERNMENT PRINTING OFFICE: 1974- 546-318:343
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