WATER POLLUTION CONTROL RESEARCH SERIES • 12020 DJI 06/71
WASTEWATER TREATMENT FACILITIES
FOR A POLYVINYL CHLORIDE
PRODUCTION PLANT
ENVIRONMENTAL PROTECTION AGENCY
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WATER POLLUTION CONTROL RESEARCH SERIES
The Water Pollution Control Research Series describes the
results and progress in the control and abatement of pollution
in our Nation's waters. They provide a central source of
information on the research, development, and demonstration
activities in the water research program of the Environmental
Protection Agency, through inhouse research and grants and
contracts with Federal, State, and local agencies, research
institutions, and industrial organizations.
Inquiries pertaining to Water Pollution Control Research
Reports should be directed to the Chief, Publications Branch
(Water), Research Information Division, R&M, Environmental
Protection Agency, Washington, DC 20460.
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WASTEWATER TREATMENT FACILITIES
FOR A
POLYVINYL CHLORIDE
PRODUCTION PLANT
by
B.E. GOODRICH CHEMICAL COMPANY
nvronma oo
3135 Euclid Avenue
Cleveland, Ohio 44115
for the
OFFICR OF RESEARCH AND MONITORING
ENVIRONMENTAL PROTECTION AGENCY
Project No. 12020 DJI
June, 1971
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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 an endorsement
or recommendation for use.
ii
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ABSTRACT
B.F.Goodrich Chemical Company has completed construction and has begun
operation of a new polyvinyl chloride (PVO production plant that includes
emulsion, suspension, and bulk polymerization processes. The wastewater
treatment system for this plant was designed to meet the stringent dis-
charge requirements of both the State of New Jersey and the Delaware River
Basin Commission.
The wastewater treatment system consists of a primary-secondary completely
mixed activated sludge process including equalization, flocculation,
clarification, mechanical aeration, nutrient addition, sludge thickening
and centrifugation, and automatic process monitoring.
Although the Company operates several PVC production plants in the United
States, none of these plants could be considered to be a duplicate of the
proposed production plant. Therefore, it was necessary to simulate the
anticipated production plant wastes by selective sampling and to conduct
pilot plant treatment studies.
This report presents summarized results of the laboratory and pilot plant
studies and a complete and detailed description of the full-scale waste-
water treatment system as constructed.
Actual operating data of the system is included and supplemented by dis-
cussion of individual unit operations and unit process performance. Ev-
aluation of a full-scale wastewater recycle and reuse system is included.
This report was submitted in fulfillment of Project Number 12020DJI under
the (partial)sponsorship of the Office of Kesearcti and Monitoring,
Environmental Protection Agency.
iii
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CONTENTS
Section
I Conclusions
II Introduction
III Design Requirements
State of New Jersey Dept. of Health
Delaware River Basin Commission
IV Design Basis
Water Usage
Waste Load
V Primary Treatment Methods
Chemical Coagulation
Dissolved-Air Flotation
Steeling
VI Toxicity Studies
VII Secondary Treatment Methods
Activated Carbon Adsorption
Contact Stabilization
Completely Mixed Activated Sludge
Page
1
3
5
11
17
19
VIII Oxygen Transfer Studies
IX Sludge Removal and Thickening
X Process Design Summary
XI Operation
XII Wastewater Recycle and Reuse
XIII Abbreviations
XIV References
29
37
41
51
67
71
73
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FIGURES
Number Page
1 Settling Column Sketch 15
2 Toxicity Curves 18
3 Biological Reactor 21
4 BOD Removal Rate vs. Load Ratio 24
5 Oxygen Transfer Apparatus 30
6 Non-Steady State Oxygen Transfer 36
7 Sludge Thickening Curve 37
8 Sludge Clarification and Thickening 39
9 Waste Treatment System Diagram 42
vi
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TABLES
Number Page
1 Raw Process Waste Characteristics 8
2 Chemical Clarified Process Waste 9
3 Coagulation Data 12
4 Settling Test Data 16
5 Pilot Plant Data 22
6 Sludge Volume Index Data 23
7 Activa-ed Sludge System Design Data 26
8,9,10 Oxygen Transfer Test Data 33,34,35
11,12, Flocculator Clarifier Performance Data 53,54,
13,14 55,56
15,16, Aeration Tank Performance Data 59,60
17,18 61,62
19,20, Secondary Trearment Performance Data 63,64
21,22 65,66
23,24 Recycle Water Quality 68,69
vii
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SECTION I
CONCLUSIONS
1. Waste equalization facilities were found to be a prerequisite to the
treatment of this type waste. Variations in organic loading, hydraulic
loading, and problems encountered with shock loadings in the pilot plant
studies substantiated this need.
2. Latex solids definitely have an adverse effect on a completely mix-
ed activated sludge system. The solids tend to cling to the biological
•floe causing stickiness and extreme reduction in organic removals. In
addition, these solids should be removed in order to minimize the diffi-
culty in keeping the aeration tank contents in suspension; in order yto
maximize oxygen transfer; and to reduce the quantity of biological inert
solids in the aeration tank.
These conclusions were supported by the initial difficulty encountered
in obtaining reproducible data from toxicity studies and by the diffi-
culties encountered in the biological treatment studies.
3. The method most suitable for removal of this type of solids and for
accomplishing primary treatment was determined to be chemical coagula-
tion-flocculation and clarification. The use of coagulants and coagulant
aids is recommended. The salt of ferric iron was found to be more eff-
ective as a coagulant as compared to alum. Calgon 227 and Nalco 670 were
found to be effective coagulant aids. The dosage requirement for coagu-
lants and coagulant aids was found to be approximately 150 milligrams per
liter, and 1 milligram per liter, respectively.
Dissolved air flotation was investigated and found to be ineffective
for this type of waste. The floe formed was extremely fragile.
4. The wastes from this type of production plant were found to be non-
toxic to a biological treatment system. It was, however, determined nec-
essary to provide waste equalization and primary solids removal prior to
such a system.
5. Of the secondary treatment methods investigated, a completely mixed
activated sludge system was found to be most applicable for this type of
waste.
Organic loading rates achievable with this system for this particu-
lar waste were found to be in a range between those for a conventional
activated sludge system and a high rate system treating domestic wastes.
A loading rate of 0.70 pounds of 5 day biochemical oxygen demand removed
per day per pound of volatile suspended solids under aeration was estab-
lished. This compares with ranges for conventional and high rate systems
of 0.1 to 0.5 and 1.25 to 4.5, respectively (11).
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Energy oxygen requirements were determined to be 0.90 pounds of oxygen
per pound of 5 day biochemical oxygen demand removed. This compares
with 0.50 for conventional systems treating domestic wastes (12).
Alpha and Beta factors were established at 0.5 and 0.96, respectively.
The Alpha factor established for this waste was lower than that commonly
found for other types of wastes. This was attributed in part to the
large amount of soaps and emulsifiers in the wastes. These values com-
pare with Alpha and Beta factors of 0.8 and 0.9, respectively, for dom-
estic wastes.
Sludge production was determined to be 0.68 pounds of volatile suspended
solids per pound of 5 day biochemical oxygen demand removed. This com-
pares favorably with values of 0.5 to 0.7 for conventional systems treat-
ing domestic wastes (11).
The aeration basin detention time was established at 6 hours. A mixed
liquor volatile suspended solids level of 2500 milligrams per liter was
determined optimum for practical design.
Aeration basin pH adjustment was provided in order to prevent the growth
of large numbers of filamentous organisms and bulking sludge.
This type of waste was found deficient in nitrogen and phosphorous levels
necessary to support biological life. Supplemental nutrients are essen-
tial.
6. Activated carbon treatment was determined to be impractical for
this waste. Poor adsorption capacities were attributed to the presence
of water soluble long-chain organic soaps contained in the wastes.
7. Laboratory data indicated the contact stabilization process was not
practical for treatment of this waste. The time requirements for adsorp-
tion of the soluble organics was found to be approximately equal to the
time required for complete degradation.
8. Suspended solids removal efficiency has averaged greater than 95
percent through the flocculator-clarifier system (primary treatment);
99 percent through the secondary system; and 98 percent through the com-
plete treatment system.
9. During initial operations of the plant biochemical oxygen demand
average removal efficiency has been in excess of 98 percent resulting
in an average effluent concentration of 2.4 milligrams per liter.
10. Wastewater recycle has been investigated and appears feasible.
Plans are underway for installation of a permanent wastewater recycle
and reuse system.
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SECTION II
INTRODUCTION
In 1966, B.F.Goodrich Chemical Company initiated plans to construct a
polyvinyl chloride (PVC) manufacturing facility on the Delaware River
in Salem County, New Jersey. This facility would employ emulsion, sus-
pension, and bulk polymerization processes (1,2,3,4) and would generate
waste waters containing monomers, polymers, organic and inorganic salts,
organic acids, resin and rubber fine solids, dispersants, wetting agents,
and catalyst.
The wastewater discharges from this manufacturing facility were subject
to the requirements of the State of New Jersey Department of Health and
the Delaware River Basin Commission. A minimum of secondary treatment
and a 90 percent removal of biochemical oxygen demand was required.
In order to competently design an industrial wastewater treatment system
to meet these established requirements, extensive laboratory and pilot
plant investigations were performed at the Company's environmental con-
trol laboratory. These investigations were performed under the direction
of graduate sanitary engineers from the Company and from Roy F. Weston &
Associates.
Both primary and secondary treatment methods were investigated. Waste
equalization; solids removal by chemical coagulation, dissolved air flo-
tation, and clarification; activated carbon adsorption; contact stabili-
zation; completely mixed activated sludge; and various other methods
were considered and studied.
This report discusses the studies performed with a major emphasis placed
on those processes found most applicable to the treatment of PVC wastes.
A description of laboratory methods and pilot; plant equipment is included.
Typical data is presented and interpreted in terms of process design.
Significant observations, specifically pertaining to the treatment of PVC
wastes, are included along with a detailed and comprehensive process de-
sign summary. In addition, full-scale plant operation is discussed in
relation to invidivual unit operations and unit processes. Problems en-
countered during initial start-up operations are presented including re-
commendations for system improvements. Actual operating data is included.
Lastly, wastewater recycle and reuse is included. The project was support-
ed in part by the Office of Research and Monitoring, Environmental
Projection Agency. Since completion of the wastewater treatment system,
over 250 persons from 25 states and 3 foreign countries have toured the
facilities.
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SECTION III
DESIGN REQUIREMENTS
The waste water effluent from B.F.Goodrich Chemical Plant in Oldmans
Township, New Jersey is subject to the Effluent Quality Requirements and
Water Quality Objectives as established by the New Jersey State Depart-
ment of Health and the Delaware River Basin Commission.
The New Jersey State Department of Health requires treatment "to
a degree providing, as a minimum, ninety percent of reduction of bio-
chemical oxygen demand at all times and such further reduction of
biochemical oxygen demand as may be necessary to maintain the receiving
waters, after reasonable effluent dispersion, as specified in the
regulations entitled, "Regulations Concerning Classification of the
Surface Wasters of the Delaware River Basin, Being Waters of the State
of New Jersey, effective July 28, 1967". (5)
The Delaware River Basin Commission on April 26, 1967, adopted
Section X of the Comprehensive Plan entitled "Water Quality Standards
for the Delaware River Basin". Section 2-1.3, Effluent Quality Re-
quirements, and Section 3-3.6, BOD Reduction of these requirements,
are quoted below.
Section 2-1.3 Effluent Quality Requirements;
(1) Minimum Treatment. All wastes shall receive a minimum of
secondary treatment, regardless of the stated stream quality
objective.
(2) Disinfection. Wastes (exclusive of stormwater bypass) con-
taining human excreta or disease producing organisms shall
be effectively disinfected before being discharged into
surface bodies of water.
(3) Public Safety. Effluents shall not create a menace to
public health or safety at the point of discharge.
(4) Limits. Discharges shall not contain more than negligible
amounts of debris, oil, scum or other floating materials,
suspended matter which will settle to form sludge, toxic
substances, or substances or organisms that produce color
taste, odor of the water, or taint fish or shellfish flesh.
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Section 2-1.3 Effluent Quality Requirements; (continued)
(5) Allocation of Capacity. Where necessary to meet the stream
quality objectives, the waste assimilative capacity of the
receiving waters shall be allocated in accordance with the
doctrine of equitable apportionment.
Section 3-3.6 BOD Reduction
The 85 percent minimum BOD reduction for secondary treat-
ment will be determined by an average of samples taken over
each period of thirty consecutive days of the year. From
December 1 through March 31 a lesser percent reduction may
be permitted by the Commission when it results from reduced
plant efficiency caused by low atmospheric temperature, pro-
vided that the BOD reduction shall not be less than an
average of 75 percent over any consecutive ten days.
B.F.Go9<3rich Chemical Company, therefore, established design objectives
to meet or exceed these requirements. The waste treatment system was
designed for 90 percent removal of ultimate biochemical oxygen demand at
winter conditions, 13°C.
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SECTION IV
DESIGN BASIS
B.F.Goodrich Chemical Cpmpany has several plants engaged in the pro-
duction of polyvinyl chloride resins, similar to those to be produced at
the Pedricktown, New Jersey plant. To estimate the design flows and
effluent waste concentrations to be expected, data from these exist-
ing plants were inspected. Obviously, corrections were necessary to
compensate for advanced process technology, improved housekeeping and
water conservation practices, and differing production capacities.
In addition, complete theoretical process material balances were
utilized for establishment of water usage and waste concentrations.
WATER USAGE
The waste water volume for the new plant was established at
800,000 gallons per day. This figure includes all process wastes,
utility water, storm drainage from areas subject to accidental spills,
storm drainage from critical tank farm diked areas, and a nominal
expansion capacity. The new plant water usage per pound of product
was established at approximately 20 percent less than the lowest
usage figures for similar processes in existing plants.
WASTE LOAD
In many cases when a new production facility is being designed,
synthetic wastes or process pilot plant wastes must be utilized for
study. Fortunately in this particular case, many of the processes
scheduled for the new plant were in production at an existing Goodrich
plant. Thus for design purposes, waste water samples were taken from
these existing processes and composited in proper proportion for the
new plant production capacities.
The analyses of all samples were in accordance with "Standard
Methods for the Examination of Water & Waste Water", 12th Edition,
published by the American Public Health Association. Dissolved
oxygen determinations were made with a YSI dissolved oxygen analyzer.
Total carbon and total organic carbon determinations were made with
a Beckman carbonaceous analyzer.
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The analyses of these composited waste samples are shown in
Table 1. With the exception of COD, these data were averaged
and utilized for design. Necessary corrections were applied to com-
pensate for factors previously discussed. A significant variation in
organic and solids loading is apparent, thus indicating a need for.
waste equalization prior to any treatment process.
TABLE 1
RAW PROCESS WASTE CHARACTERISTICS*
Date
3/29/68
3/30/68
3/31/68
4/10/68
4/11/68
4/16/68
4/17/68
4/18/68
4/19/68
4/22/68
4/23/68
4/24/68
4/25/68
4/26/68
4/30/68
5/01/68
5/02/68
5/03/68
5/06/68
5/07/68
COD
mg/1
1600
1372
2660
7440
1068
1960
3064
3885
1546
6547
4464
4464
2381
2142
1904
5356
4256
4365
6994
1760
TC
mg/1
460
545
590
2600
380
800
848
860
460
710
1410
1310
705
1000
390
1840
1520
1280
790
270
TS
mg/1
980
1728
1267
4420
1068
2363
1683
1347
2098
1359
2486
1936
4060
3290
2884
2808
VTS
mg/1
666
1040
880
3816
483
447
1148
1079
1468
1032
1712
1249
3395
3044
1314
1431
SS
mg/1
436
992
2888
528
456
678
348
1902
560
1628
1180
2688
1392
976
808
VSS
mg/1
376
974
2856
516
412
632
340
1866
536
1584
1112
2620
1344
952
784
Turbidity
JTU
245
1760
8500
350
168
1070
1680
190
3200
2500
3800
2140
2400
Average 938 2230 1514 1164 1125
*Necessary corrections have not been applied to this data.
COD = Chemical Oxygen Demand
TC = Total Carbon
TS = Total Solids
VTS = Volatile Total Solids
SS = Suspended Solids
VSS = Volatile Suspended Solids
2160
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Design parameters for organic loading were handled in a different
manner. It was found that consistent and reproducible BOD5 (5 day
biochemical oxygen demand) results could not be achieved until the raw
process wastes had been chemically clarified. Table 2 shows
BODc and COD data on chemically clarified process wastes. These data
were ranked arithmetically and statistically analyzed. Design values
for 8005 and COD were then selected, such that the probability of
exceeding these values was less than 10 percent.
TABLE 2
CHEMICALLY CLARIFIED PROCESS WASTE
ORGANIC LOADING
RANKED JDATA
100
BOD N n + 1 COD
356 1 3.3 820
410 2 6.7 832
427 3 10.0 843
482 4 13.3 920
490 5 16.7 940
493 6 20.0 964
543 7 23.4 976
548 8 26.7 1009
567 9 30.0 1016
583 10 33.4 1091
615 11 36.7 1115
629 12 40.0 1136
647 13 43.4 1178
658 14 46.7 1190
666 15 50.0 1192
690 16 53.4 1220
714 17 56.6 1270
744 18 60.0 1280
746 19 63.4 1309
752 20 66.6 1320
753 21 70.0 1360
767 22 73.5 1440
802 23 76.7 1449
808 24 80.0 1449
873 25 83.4 1473
901 26 86.7 1557
1036 27 90.0 1599
1254 28 93.4 1768
1470 29 96.7 3030
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In summary, the following data were developed characteristic of the
raw process wastes. The BODg and COD results represent chemically
clarified process wastes.
Waste Volume = 800,000 GPD
BOD5 = 720 mg/1
COD = 1,285 mg/1
TS (Total Solids) = 2,000 mg/1
SS (Suspended Solids) = 1,000 mg/1
VSS (Volatile Suspended Solids) = 950 mg/1
In addition, variations in both hydraulic and organic loading
were observed. Moreover, it was found that chemical clarification of
the wastes was necessary in order to achieve reproducible BOD5 data.
This also further substantiates the need for waste equalization.
10
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SECTION V
PRE1ARY TREATMENT METHODS
The waste streams to be treated originate predominantly from
emulsion, suspension, and bulk polymerization processes. In general
the waste can be characterized as milky white in color and containing
various amounts of monomers, polymers, organic and inorganic salts,
organic acids, resin and rubber fine solids, dispersants, wetting
agents, catalysts, and trace amounts of heavy metals. In addition, the
waste may be further characterized by the data in Table 1, Section IV.
This section discusses the laboratory investigations performed in
order to develop a primary treatment method applicable to this
waste. The methods investigated consisted of chemical coagulation,
dissolved air flotation, and settling. The procedures and apparatus
used will be discussed; data will be presented; and conclusions will
be drawn.
CHEMICAL COAGULATION
In general, the solids in the wastewater can be described as 80 percent
settleable, 15 percent colloidal, and 5 percent floating. To remove col-
loidal solids, to settle floating solids, or to raise settleable solids,
a coagulant is needed. A coagulant will stabilize the colloidal mater-
ials and form floe materials, thus enhancing sedimentation or flotation,
depending on the particular application.
A coagulant aid may also be used with a coagulant in order to pro-
mote the formation of larger floe particles, thus enhancing solids
removal.
Several coagulants and coagulant aids were used to determine the
right combination for this particular waste effluent. The coagulants
tested were alum, fsrri-floc, and ferric chloride. The coagulant aids
used were anionic, cationic, and non-ionic.
The Phipps-Bird jar test apparatus was used when performing these
studies. The equipment consists of six mixers with variable speeds
(0 to 100 rpm) and six one-liter beakers. Each waste sample tested
was one liter in size.
11
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In all cases, each sample was mixed at 100 rpm and the chemicals
were added. After two minutes of the flash mix, the mixer was adjusted
to 50 rpm for five minutes. The final 10 minutes were conducted at
10 rpm in order to promote floe growth. It was important to mix the
coagulant first at 100 rpm and then add the coagulant aid. Reversing
the order would not produce a satisfactory floe particle.
When testing for the type of coagulant, each coagulant was tested
alone; coagulant aids were not used at this point. The results of the
coagulation tests indicated the salt of the ferric ion worked best. The
alum worked fairly well. Good results with alum were achieved only in a
narrow pH range close to 8. The Fe''' worked well over a wide pH range
(4.0 to 10.0) and because of this was considered best for the results
needed for this system. The optimum dosage for the Fe''' was 150 mg/1
as FeClo-
|i I
The coagulants aids w.ero tested using the Fe' ' ' at an optimum dos-
age, as indicated by the results of previous tests. The results indi-
cated that a slightly cationic to non-ionic polyelectrolyte was the best
for the purposes of the study. The chemicals that worked well were Calgon
227"and Nalco 670. The optimum dosage of polyelectrolyte was 1 mg/1.
The data in Table 3 shows typical results obtained using a composite waste
sample similar to that which was expected to exist at the Pedricktown plant.
Note that the coagulant dosage was 150mg/l, and the coagulant aid dos-
age was lmg/1. Turbidity was used as a parameter for solids removal
efficiency. In all cases, a significant amount of turbidity was re-
moved. COD was also used as a measure of efficiency; however, the COD
is only a function of the removal of solids which have soluble organics
attached to them.
TABLE 3
COAGULATION DATA
Before Coagulation
After Coagulation
Sample
1.
2.
3.
4.
Turbidity
1800 JTU
860 JTU
400 JTU
950 JTU
COD
778 mg/1
1532 mg/1
1863 mg/1
2621 mg/1
_pJH_
9.5
11.0
11.0
12.4
5.7
9.8
6.7
5.8
COD
778 mg/1
1109 mg/1
1552 mg/1
1935 mg/1
Turbidity
(Clarified)
10 JTU
44 JTU
55 JTU
24 JTU
* Suspended
Solids
1114 mg/1
779 mg/1
671 mg/1
427 mg/1
NOTE: 1. 150 mg/1 FeClo coagulant dosage and 1 mg/1 coagulant aid dosage
was used for all samples.
The final suspended solids data
before settling. These figures
treatment design purposes.
is that of the total sludge
were obtained for sludge
12
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In conclusion, it was determined that coagulation is an effective
method of solids agglomeration from the waste under investigation. The salt
of ferric ion was found to work best at dosages ot approximately 150
mg/1. In addition, Calgon 227 and Nalco 670 coagulant aids were found
to enhance solids removal. The order of addition of the coagulant and
coagulant aid was found to be of importance. The coagulant must be
mixed first.
Once a suitable dosage of coagulant and coagulant aid was deter-
mined, the next step was to determine the best method of solids removal.
The methods of dissolved-air flotation and settling were investigated.
These methods were evaluated by the volume rate of which suspended
solids were removed.
DISSOLVED-AIR FLOTATION
To remove waste materials, using the principle of dissolved-air
flotation, air is dissolved in water under pressure, injected into the
waste sample, and released. The result is thousands of micro-bubbles
rising to the surface. These small bubbles cling to the floe particles
and suspended matter carrying them to the surface.
The equipment used consisted of a one-gallon pressurizing cylinder,
a one-liter graduated cylinder, and the Phipps-Bird mixing apparatus
described previously. The procedure followed for coagulating the waste
was the same as that described in the previous section. After a sample
had been coagulated, a portion was put into the graduated cylinder.
Before the floe could settle, air-saturated water under approximately
40 PSIG pressure was injected into the base of the cylinder. The micro-
bubbles released carried the materials to the surface.
Dissolved-air flotation proved very ineffective for this particular
waste. The floe formed was extremely fragile and acceptable solids re-
moval could not be accomplished.
SETTLING
The equipment used for the settling consisted of an eight foot
plexiglass column with sample ports at each foot of depth as shown in
Figure 1. The coagulant and coagulant aid dosage was known from previous
jar tests. The dosage for the column was based on a five-gallon sample
volume.
The procedure consisted of thoroughly mixing the coagulant and co-
agulant aid into the five-gallon sample. This sample was then pumped
into the plexiglass column. A multi-blade, 6 RPM agitator inside the
column was used to flocculate the waste for a period of 15 to 20 minutes.
Following flocculation, samples were taken from the one and six foot
depth sample ports and were considered zero time samples. The average
13
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of the two zero time samples was used as the initial suspended solids
for the waste. At set time intervals, additional samples were taken
from one, two, four, and six foot sample ports. All samples were
analyzed for suspended solids.
The data shown in Table 4 indicates the suspended solids at various time
intervals and depths in the column for both coagulated and uncoagulated
wastes. The depths indicated are measured from the top of the column
down. The results clearly indicate the need for chemical coagulation.
As shown, the maximum suspended solids removed at a point of one foot
depth in the column was 48 percent of the total for uncoagulated wastes.
For coagulated wastes, approximately 95 percent of the suspended solids
were removed after 30 to 60 minutes of settling.
All data completed on settling tests gave results of 95 percent suspended
solids removal. From this data a primary clarifier overflow rate was
established at 1000 GPD/ft2, and the detention time at 2.8 hours. App-
ropriate scale-up factors were used to compensate for the ideal settl-
ing conditions of the study.
14
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FIGURE 1
SETTLING COLUMN
Stirring Mechanism
Sample Ports
81 x 6" Plexiglass Column
1'
12"
6"
I
15
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TABLE 4
SETTLING TEST ON UNCOAGUIATED EFFLUENT
Time Suspended Solids % Suspended Solids Removed
Minutes at Indicated Depths mg/1 at Indicated Depths
1' 2' 4' 61 I1 2f 4' 61
0
10
20
30
60
496
390
260
270
480
476
320
330
390
320
320
376
440
496
220
270
380
360
21
48
45
3
4
35
33
21
35
35
25
11
66
45
23
27
120 260 390 360 410 48 21 27 17
180 280 340 480 380 43 31 3 23
1,080 280 290 500 320 43 41 xx 35
SETTLING TEST ON COAGULATED EFFLUENT
Coagulant Dosage = 150 mg/1
Time Suspended Solids % Suspended Solids Removed
Minutes at Indicated Depths mg/1 at Indicated Depths
1' 2' 4' 6' 1' 2' 4f 6'
0
1
5
10
20
30
60
90
130
330
199
78
46
35
26
494
402
209
102
55
41
34
14
8
537
256
111
62
51
34
39
21
799
624
461
163
57
36
39
37
31
49
69
88
93
95
96
38
68
84
91.5
94
95
98
99
17
60
83
90.5
92
95
94
97
3
29
75
91
96
94
94
95
16
-------
SECTION VI
TOXICITY STUDIES
During the preliminary waste characterization studies, extreme difficulty
was encountered in developing consistent and reproducible BOD data. This
factor indicated the possibility of elements in the wastes which were
toxic to microorganisms commonly utilized in wastewater treatment opera-
tions. Therefore, before detailed biological treatment studies were be-
gun, toxicity studies were conducted. Waste streams were investigated on
both an individual and composite basis.
These studies consisted of batch tests using standard BOD deter-
minations. A series of BOD's were prepared with waste concentrations
ranging from 0 to 98 percent. Prior to setting up the BOD determina-
tions the wastes were chemically clarified. To insure that biode-
gradable materials were present, 0.12 milligrams of glucose was added
to each BOD bottle. Acclimated seed, nutrients, and dilution water
were added before incubation. Dissolved oxygen (DO) measurements were
taken before and after incubation. A YSI DO analyzer was used for
oxygen determinations.
A plot of DO concentration versus waste concentration will indi-
cate if toxicity is present. If no toxicity is present, the DO
concentration will decrease as the waste concentration increases.
This will continue until all DO is depleted. If toxicity is present
the DO will deplete to a point where the waste concentration becomes
toxic. Beyond this point the DO depletion will decrease with increas-
ing waste concentration. Figure 2 shows the results of toxicity
studies on composite wastes. Curve B illustrates a toxic waste. It
was later found that this toxicity was due to an excess of hexavalent
chromium from a process spill.
It was concluded that the combined wastes under investigation would
not be toxic to a biological system. In addition, these studies
further substantiated the need for providing equalization and spillage
isolation facilities prior to a biological system.
17
-------
Curve A - No Toxicity
X
\
\
\
S
o
01
I—I
a
c 4
00
•X3
-------
SECTION VII
SECONDARY TREATMENT METHODS
In order to achieve the treatment levels as outlined in Section III,
it was necessary to provide secondary treatment. The methods of second-
ary treatment considered consisted of activated carbon and various
biological systems.
Activated carbon adsorption isotherm tests were conducted on the chem-
ically clarified wastes. These tests indicated that the adsorption
capacity of activated carbon was relatively poor for these particular
wastes. This poor adsorption capacity was attributed to water soluble
long-chain organic soaps contained in the wastes. It was thus concluded
that activated carbon treatment would not be a practical or economical
method of achieving secondary treatment. Therefore, no further carbon
studies were conducted.
The biological systems considered consisted of an aerated lagoon, a
completely mixed activated sludge system, and contact stabilization.
The aerated lagoon was eliminated due to excessive area requirements
and the degree of treatment attainable from this type process.
Laboratory data indicated that the contact stabilization process was
not practical. The time requirements for adsorption of the soluble
organics was found to be approximately equal to the time required for
complete degradation.
4
Past experience in the waste treatment field has shown the completely
mixed activated sludge process to be highly efficient and more cap-
able of withstanding shock loading. For this reason it was decided to
further investigate the feasibility of utilizing this system.
At this point a completely mixed activated sludge pilot plant process
was designed and operated in order to develop design parameters for a
treatment system.
19
-------
The consulting firm of Roy F. Weston & Associates was contracted
to provide assistance in these studies. Design data was developed from
both the continuous pilot process and from batch tube run studies which
utilized the sludge produced in the continuous pilot process. The tube
runs were conducted in accordance with procedures developed by the con-
sultant (8, 9, 10) as described in the referenced report. No further des-
cription is included in this report.
The data developed from the continuous and batch studies compared
closely with the exception of oxygen requirements. With this exception,
the data developed from the continuous pilot plant was used for design
purposes since the continuous system represented the waste stream over
a longer period of time.
The following paragraphs describe the equipment and the methods of
operation used in the continuous pilot plant studies. Data on the final
pilot plant study will be presented and discussed. Calculations leading
to the selection of process design conditions will be presented and im-
portant observations will be discussed.
CONTINUOUS PILOT PLANT
In these studies a completely mixed activated sludge system was
simulated by providing sludge recycle and mixing of the aeration tank
contents. The equipment used is shown in Figure 3 and consisted of
a 55-gallon equalization and feed tank, a 6-gallon aeration tank, a
5-gallon conical clarifier, aeration diffuser, and appropriate pumps.
The biological system was started by placing a mixture of activated
sludge from a nearby sewage treatment plant in the aeration tank. Chemi-
cally clarified process waste was placed in the feed tank. Essential
nutrients were added. The waste feed pumps were started at a low initial
feed rate in order to allow acclimatization of the organisms. The process
was operated under various conditions of feed rate, detention time,
sludge recycle rate, and at various mixed liquid volatile suspended
solids levels (MLVSS). Some of the data developed is shown in Table 5
The symbols and terms used are discribed below.
Ql = Feed rate of the chemically clarified process
wastes, ml/min.
Q« = Sludge recycle rate, ml/min.
T = System operating temperature, °C.
L = BODc of the chemically clarified process
wastes, ng/1.
20
-------
Feed Pump
^
i
Chemically
Clarified
Waste Feed
and
Nutrients
55-Gal.
Feed Tank
Air Supply
6-Gal. Aeration Basin
5-Gal. Clarifier
Settled Sludge
*<
Sludge Recycle Pump
Clarified
Effluent
w
H
1
1
-------
TABLE 5
Date
4/5
4/6
4/10
4/11
4/15
4/16
4/19
4/20
4/21
4/22
4/23
4/24
4/25
4/27
4/28
4/29
5/1
5/2
5/3
5/4
5/5
5/6
Ql
10
17
24
24
30
30
47
50
50
58
50
48
48
66
48
55
48
64
66
66
66
65
ANALYTICAL DATA
CONTINUOUS PILOT PLANT STUDIES
02
10
17
24
24
30
30
47
50
50
58
50
36
36
67
50
59
51
70
72
72
72
68
T
16
23
21
20
20
19
22
22
25
23
20
20
17
20
22
24
20
17
22
21
20
18
L0
802
873
901
752
636
629
1470
753
2120
1328
1236
2100
2000
1096
1019
1515
1065
1113
1348
1158
1244
928
if
26
26
24
24
14
18
15
13
25
57
25
16
30
40
25
50
36
44.3
55.0
50.0
44.0
23.0
Si
1780
1220
2160
1980
2130
1900
3020
2950
4600
3290
3190
3700
4670
4030
3180
3500
3860
4190
2940
4290
4630
3820
1133
670
473
473
378
378
242
227
227
186
227
270
270
186
220
204
238
179
173
173
173
175
22
-------
Le = Equilibrium BODg which is equivalent to the
effluent BODc, considering the system is
operating continuously at equilibrium.
S^ = MLVSS in the aeration tank, mg/1.
t£ = Detention time in the aeration tank, min.
From the data in Table 5 and the system geometry, the relation-
ship of the BODc removal rate coefficient (r) to the load rate Li/Si
can be developed as shown in Figure 4. The BODg removal rate co-
efficient is a measure of the rate of BODc removal from the aeration
tank under equilibrium conditions; that is,
r = Li - Le min. ~1
where L. = BODe of the aeration tank influent, mg/1
+ Q2 Le
Ql +Q2
The load ratio = L./Sj[, mg/1 BOD5/mg/l MLVSS, and may be defined
as a measure of the food to microorganism ratio in the aeration tank.
Once this relation was established, then various process design and
operating conditions were investigated in order to define optimum de-
sign parameters in terms of physical equipment capacities and operation-
al flexibility. Calculations were made at MLVSS levels of 1500, 2000,
3000, 3500, and 5000 mg/1 and at three sludge volume index (SVI) levels;
100, 150 and 200 representing conditions of good settling, average
settling, and poor settling respectively. These values were estab-
lished based on the laboratory data shown in Table 6.
Table 6.
SLUDGE VOLUME INDEX DATA
DATE MLSS (mg/1) SVI
4/7 1890 97.8
4/9 2090 83.7
4/17 2900 62.1
4/18 3060 68.6
4/23 3490 68.8
4/24 3980 61.6
4/25 4670 63.2
4/26 5320 59.2
4/27 4380 57.1
4/28 3570 58.8
4/29 3920 63.8
4/30 5440 53.3
5/1 4640 62.5
23
-------
FIGURE 4
BOD REMOVAL RATE VS LOAD RATIO
H
S3
W
0.1
O
§
CQ
Q)
II
M
d)
4-J
.02
.01
.005
_L
0.05 0.1
LOAD RATIO
0.2
0.5
24
-------
Note that the SVI shown in the Sludge Volume Index Data on the
preceding page, was less than 100 for all MLVSS levels, indicating
good sludge settling characteristics.
For the calculations, a design flow of 0.8 MGD was used at a BODc
concentration of 720 mg/1. All calculations were based on a 90 percent
BOD removal at winter conditions (13° C.).
The following equations were used for calculating the data shown
in Table 7.
(1) MLVSS (mg/1) = 907, MLSS MLSS =
(2) Recycle SS (mg/1) = 1 x 106
SVI
(3) Percent Recycle = _ MLSS _
of Forward Flow Recycle SS - MLSS
(4) Basin Volume = (Design Flow Rate) (1 + Percent Recycle) t
e
where te = detention time
= Li - Le
r -^goQ Le
where r is determined from Figure 4 and
corrected to 13°C.
Analysis of the calculated data in Table 7 show a considerable
variation in recycle rates, aeration basin volumes, and detention time
for the MLVSS levels investigated. Variation at the individual MLVSS
levels for the selected SVl's were less extreme. It was desired to
select a MLVSS concentration sufficiently high in order to minimize basin
volume while at the same time holding the sludge recycle rates within
reasonable operational ranges. For these reasons, a MLVSS level of 2500
mg/1 and an SVI of 150 was selected for design parameters. Up to this
2500 mg/1 level, the aeration basin volume requirements remained essen-
tially constant for all SVI levels up to 200. In addition, the corres-
ponding sludge recycle rate requirements are manageable for the SVI
levels up to 200.
As previously indicated, the oxygen requirements were developed
from the tube run studies. It was found that 0.9 pounds of energy
oxygen were required per pound of BOD^ removed (equivalent to 4100
pounds oxygen per day). In addition, the endogenous oxygen requirement
for the design VSS level was found to be 875 pounds per day. In com-
bination, the total oxygen requirement amounted to 207 pounds per day
(equivalent to 70 mg/l/hr.).
25
-------
TABLE 7
NO
Activated
MLVSS (mg/1)
SVI
Recycle (%)
Recycle (GPM)
Process Eff. (%)
Li, (fflg/1)
Basin Volume ,
Gallons X 10
Detention Time
Min. at "r" 13°C.
100
20
112
88.1
611
42.8
640
1500
150
33.
186
87
556
43.
590
Sludge System Design Data
200
4 50
278
85.9
505
9 43.2
500
100
38.5
214
86.6
540
34.8
450
2500
150 200
71.5 125
398 696
84 80
450 360
35.4 32.0
370 255
100
63.6
354
84.6
468
30.1
330
3500
150 200
141 350
785 1950
78.9 66.7
341 216
23.5 18.0
175 72
-------
Excess sludge production values also were determined from the
tube run studies. It was found that 0.68 pounds VSS were produced
per pound of BOD^ removed; 51 pounds of VSS were destroyed per 1000
pounds VSS under aeration; and that 50 mg/1 SS would be lost in the
secondary clarifier effluent.
In summary, the design parameters developed from the biological
studies, which were later used for design purposes, consisted of:
MLVSS Concentration = 2500 mg/1
SVI = 150
Sludge Recycle Rates = 0-125%, normal = 71.5%
Aeration Basin Volume = 354,000 gallons
Detention Time = 370 minutes
Oxygen Requirements = 70 mg/l/hr.
Sludge Production = 0.68# VSS/#BOD5 removed
In addition to these specific parameters, several important obser-
vations were made relative to the biological treatment of PVC wastes.
The significance of these observations was incorporated into the system
design. Such observations are discussed below.
1. Solids removal prior to biological treatment -
It was found that latex solids definitely have an adverse
effect on a completely mixed activated sludge system. These
solids tend to cling to the biological floe causing sticki-
ness and extreme reductions in organic removal. In*addition,
these solids should be removed in order to minimize the
difficulty in keeping the aeration tank contents in suspension;
in order to maximize oxygen transfer; and in order to reduce
the quantity of biologically inert solids in the aeration
tank.
2. pH adjustment -
Provisions should be made for caustic addition in order to
prevent the pH from dropping significantly below 7.0. On
two separate occasions the pH in the aeration tank dropped
to approximately 5.0 for short periods of time. This resulted
in the presence of large numbers of filamentous organisms
and a bulking sludge.
3. Supplemental nutrients -
This type oZ waste was found to be deficient in nitrogen
and phosphorous levels necessary to support biological
life. Supplemental nutrients are essential.
27
-------
Equalization -
The waste from this type of production process was found to
be variable in hydraulic and organic loading. A one day
waste equalization time is recommended in order to prevent
"shocking" of the biological treatment process.
28
-------
SECTION VIII
OXYGEN TRANSFER STUDIES
Oxygen transfer studies were conducted to determine the transfer charac-
teristics of the waste. In order to size aeration equipment it was nec-
essary to know alpha (a) and beta (p). Alpha is the ratio of the trans-
fer coefficient in waste water to the transfer coefficient in tapwater.
Beta is the ratio of oxygen saturation values.
The equipment used is shown in Figure 5. Mixed liquor was placed in
the basin and the surface aerator started. Once the test had started
none of the equipment could be moved. Changing the position of the
aerator or basin would change the overall oxygen transfer coefficient
(K^a) that was obtained, and therefore give an invalid value for a,
Waste water was fed into the basin for the purpose of determining an
equilibrium dissolved oxygen value. When the feed is started the dis-
solved oxygen will begin to drop. When the dissolved oxygen stabilizes,
this value is recorded and the oxygen uptake rate is measured by record-
ing DO versus time.
The basin was then emptied, cleaned, and refilled with tapwater without
moving the basin. The dissolved oxygen was then removed using sodium
sulfite. Cobaltous chloride was used as the catalyst. The surface
aerator was then started at the same speed as was used on the mixed
liquor. The values of DO versus time were recorded as oxygen was trans-
ferred to the water.
The saturation values (Cg) were obtained by aerating supernate and tap-
water until saturation was obtained.
The rate of diffusion of oxygen from the gas to the liquid depends on
the temperature, the driving force (concentration gradient), the area
across which diffusion takes place, and the characteristics of the waste.
The process is defined by Fick's law:
N = (DLA) d£ (i)
dy
where:
N = mas transfer per unit time
A = cross sectional area
dc/dy = concentration gradient perpendicular to cross-
sectional area
DT = diffusion coefficient
29
-------
Aerator Mechanism
u>
o
0 u u u trtru
Basin
Clamp
Feed Pump
•n
H
o
@
M
Ul
Overflow
-------
Assuming that equilibrium exists at the interface, Lewis and
Whitman developed the two film concept. This concept considers in-
finitely small stagnant films at the gas and liquid interface through
which the gas is transferred. Pick's law can be rewritten as:
N = KLA (CS-C) = KgA (pg-p) (2)
where :
KL = liquid film coefficient
Kg = gas film coefficient
C = dissolved oxygen concentration
p = partial pressure of oxygen
For oxygen and other slightly soluble gases, the liquid film will
control. Since N = (dc/dt)V equation (1) can be re-expressed as:
dc/dt = KL(A/V) (CS-C) (3)
For convenience, KT (A/V) is usually expressed K^a which is the over-
all transfer coefficient.
dc/dt = KLa (CS-C) (3-A)
In an activated sludge system there is a simultaneous oxygen up-
take while the oxygen is being transferred. Equation (3) becomes:
dc/dt = Kja (Cs-C) - r (4)
where:
r = biological oxygen uptake rate
If, as in the laboratory test, the system is in steady state:
dc/dt = 0
and KLa = r/C -C (5)
To find K-^a on tap water, a non-steady method must be used. Re-
arranging equation (3-A) and integrating both sides gives:
_3£_ - (KLa) dt (6)
Icl o^c - / I2, (W dt (7)
Aln (CS-C) = (KLa) At (8)
KLa = Aln (Cfi-C) (9)
At
31
-------
From equation (9) it can be seen that BL a would be the slope of a plot
of In (C -C) versus time.
Knowing the two KLa's, the value of
a = Kj a Waste Water
KLa Tap Water
can be determined.
P is equal to the saturation concentration in wastewater divided by
saturation concentration in tap water.
The value of a obtained was considerably lower than that normally found
in domestic waste. This was due to waste characteristics. The presence
of surface active agents and other organics will have a profound effect
on KT a. Molecules of surface active materials will orient themselves on
the interfacial surface and create a barrier to diffusion. The excess
surface concentration is related to the change in surface tension, as
defined by the Gibbs equation, such that small concentrations of surface
active material will depress K^a, while large concentrations will exert
no further effect. The absolute effect of surfactants on KLa will also
depend on the nature of the aeration surface. Less effect would be
exerted at a highly turbulent liquid surface, since the short life of
any interface would restrict the formation of an adsorbed film. Con-
versely, a greater effect would be exerted at a bubble surface because
of the relatively long life of the bubble as it rises through an aeration
tank. In some cases, the reverse effect may be noticed. The decrease in
surface tension will decrease the size of bubbles and this will increase
the area volume ratio (A/V). If the increase in A/V exceeds the decrease
in K. , then the KTa will increase over that in water. These cases, how-
ever, are unusual.
The actual data and calculations of the three tests are shown in
Tables 8, 9, and 10, and Figure 6. The average a value of the three runs
is 0.434. The average of 0 is 0.963. Since the consultant indicated
that a higher a value was usually observed in the field than in labora-
tory studies, a value of a = .5 was used for design. With values of
a and |3 and the oxygen requirement developed in Section VII, and aerator
manufacturer can size necessary equipment.
32
-------
.28
3.10
5.38
6.82
7.70
8.32
8.69
8.90
8.92
6.10
3.82
2.38
1.50
.88
.51
.30
TABLE 8
OXYGEN TRANSFER STUDIES
TEST #1
A. Determination of K^a of tap water
Temperature 18.2° C. 02 Saturation 9.20
Time (min.) P.O. (mg/1) CP-C
0
1
2
3
4
5
6
7
KLa = 2.303 X .203 = .474 min."1
B. Determination of K^a of waste water
Temperature - 18.2° C.
Dissolved Solids 1,067 mg/1
Saturated Oxygen concentration (corrected for dissolved
solid)
Supernate 8.74 mg/1
Oxygen transfer
a. Equilibrium oxygen concentration 2.90 mg/1
b. Biological uptake rate 67.9 mg/l/hr.
Transfer coefficient
Kja = r/Cs-C e
KLa = 67.9 = 11.82 hr."1 = .197 min."1
8.74 - 2.90
C. Comparisons
1. a = KLa waste water = .197 = .417
NT a waste water
KLS tap water
C0 waste water
Cs tap water
= .197
.474
= 8.74
9.20
2. « = U0 waste water = e./f = .950
33
-------
B.
C.
TABLE 9
OXYGEN TRANSFER STUDIES
TEST #2
Determination of Kj-a of tap water
Temperature 18.3° C. 02 Saturation 9.30 mg/1
Time (min.)
0
0.5
0.75
1.00
1.5
2.0
2.5
3.0
3.5
D.O. (mg/1)
.50
2.45
3.32
4.12
5.38
6.38
7.15
7.65
8.05
Cg-C
8.80
6.85
5.98
5.18
3.92
2.92
2.15
1.65
1.25
KLa = 2.303 X .242 = .565 min.'1
Determination of K^a of waste water
Temperature - 18.3° C.
Dissolved Solids 932 mg/1
02 saturation (corrected for D.S.) 9.08 mg/1
Oxygen transfer
a. Equilibrium oxygen concentration 6.10 mg/1
b. Biological uptake rate 47.3 mg/l/hr.
Transfer coefficient
KTa = r/C -Ca
KLa = 47.3/9.08 - 6.10
Comparisons
15.9 hr.
-1
.265 min.
-1
1
9
a
ft
_ K^a waste water
Kj^a tap water
_ Cs waste water
Cg tap water
.267
.565
9.08
9.30
= .473
= .976
34
-------
TABLE 10
OXYGEN TRANSFER STUDIES
TEST #3
Determination of K^a of tap water
Temperature 18.0° C. Oo Saturation
9.42
Time (min . )
0
0.25
0.50
0.75
1.00
1.50
2.00
2.50
3.0
3.5
4.0
D.O. (mg/1)
1
2.05
3.00
3.90
4.68
5.90
6.80
7.40
7.95
8.30
Cg-C
8.42
7.37
6.42
5.52
4.74
3.52
2.62
2.02
1.47
1.12
.82
KLa
= 2.303 X .254 = .592 min.
-1
Determination of
of waste water
Temperature - 18.0° C.
Dissolved Solids .220 mg/1
02 Saturation (corrected for D.S.)
Oxygen transfer
Equilibrium oxygen concentration
a.
b.
Biological uptake rate
9.05
5.58 mg/1
50.4 mg/l/hr.
Transfer coefficient
Kra = r/Cq-C
TJ s e
KLa = 50.4/9.05 - 5.58 = 14.6 hrT1 = .243 min.'1
Comparisions
1. a =
2. 0 =
K^a waste water
KLa tap water
Co waste water
C0 tap water
= .243
.592
= 9.05
9.42
.412
.962
35
-------
FIGURE 6
iNON-STEADY STATE OXYGEN TRANSFER STUDIES
o
i
ID
o
J_
z
Time (rain)
36
-------
SECTION IX
SLUDGE REMOVAL AND THICKENING
At this point it was apparent that a completely mixed activated sludge
process would be utilized for achieving secondary treatment, thus, it
was necessary to develop design parameters in order to size the nec-
essary final clarification facilities and to size both chemical and bio-
logical sludge thickening tanks.
Laboratory settling studies were performed, similar to those described
in Section V. A homogenous sample of the aeration basin effluent was
placed in an 8 foot by 6 inch diameter settling column. Data was taken
relating sludge interface level with settling time. A typical curve,
as shown in Figure 7, can be developed from such data.
Figure 7
Sludge Thickening Curve
01
0)
o
cd
s !
H
Q) *+•
GO V
•o
CO
Free Settling Range
Range of Intermediate
Sludge Compaction
Maximum Sludge
Compaction
Settling Time
It is apparent from this curve that various degrees of sludge compaction
can be achieved depending upon the settling time allowed. Design over-
flow rates can be calculated from various degrees of sludge compaction
from the data developed in the settling studies.
37
-------
Figure 8 shews a summary of the results of several individual
settling studies performed on wastes of varied solids concentrations.
From this figure a clarifier overflow rate can be determined for a
specified MLSS level. Since these data were developed under ideal
settling conditions, correction factors must be applied in order to
compensate for the effects of turbulence, short circuiting, and inlet
and outlet losses.
The secondary clarifier was designed such that the sludge would
settle to an approximate 1 percent consistency. This resulted in a
design overflow rate of 565 GPD/ft.2 and a design detention time of
approximately 3 hours.
Design parameters for both the chemical and biological thicken-
ing tanks were developed in a similar manner. Chemical and biological
sludge compaction levels were established at 8 percent and 2 percent
consistency, respectively. The resultant design parameters were:
Chemical Sludge Thickener
Overflow Rate = 160 GPD/ft.2
Detention Time = 11.3 Hours
Biological Sludge Thickener
Overflow Rate = 174 GPD/ft.2
Detention Time = 10.8 Hours
In addition to these studies, preliminary laboratory studies
were performed in order to determine the feasibility of further sludge
dewatering by centrifugation. The results from these preliminary
studies were quite favorable. Equipment manufacturers were consulted
for further details. Recommendations were made to install a centrifuge
for sludge dewatering.
38
-------
01
CO
fXi
03
,—I
U
FIGURE 8
SLUDGE CLARIFICATION AND THICKENING
100
800
400
Free Settling
Thickening to 1%
Thickening to
Maximum
20003000 4000
Inlet MLSS (mg/1)
§
0)
-------
SECTION X
PROCESS DESIGN
The laboratory studies, as discussed in the previous sections of this
report, provided basic design parameters for the Pedricktown Plant Waste
Treatment System. Engineers of Roy Weston & Associates and the B.F.
Goodrich Chemical Company developed the detail process design for such
a system.
This section includes a summary of the resultant treatment system process
design including a process flowsheet to facilitate understanding of the
system. No attempt was made to include design calculations.
41
-------
Igyasr /yag
KQTTTFnT
.
L- "- --
FIGURE 9
Waste Treatment System Diagram!
I*— ™
•nmr *zr A!ZT
fftT ^MVMT4P!Mf ^VfliB NlM
-------
Equalization Tank (TK-8Z)
This tank is sized at 950,000 gallons total to provide an equali-
zation for both organic and hydraulic loads. The need for this facility
was determined in part by the pilot plant studies and individual analy-
sis of samples taken from an existing plant. The change in organic
loading over a period of a day was great enough to justify this tank to
prevent "shocking" a biological process following in the system. The
following is a summary of the design of this tank:
Design Flow - 0.8 MGD
Detention Time - 1 day
Agitator - 25 HP, 30 RPM, 95" in dia. turbine
Dimensions - 90 ft. dia. by 20 ft. straight side
Construction - steel, above ground, baffled, pumped
influent, pump?d effluent.
Chemical Flash Mixing Tank (TK-30Z)
The purpose of this tank is to give approximately two minutes re-
tention in each of two compartments, so that the coagulant and coagulant
aid can be put into solution. Two tanks were provided in order to add
coagulant and coagulant aids in the proper order. The agitation is
quite vigorous to give good shear, as well as good blending. The
following is a summary of the design of this tank:
Design Flow - 0.8 MGD
Detention Time - 4 minutes (total)
Agitator - 2000 GPM pumping capacity
Dimensions - 7 ft. by 14 ft. rectangular by 7 ft.
straight side, 4 ft. SWD (Side Water
Depth)
Construction - steel
Waste Water Transfer Pumps (PU-30 & 31Z)
These two pumps are sized to handle the design flow of 0.8 MGD
individually. One pump will be used as a spare. Flow from these
pumps is adjusted by a manual regulator. A magnetic flow meter ad-
justs a control valve to allow through the set flow desired.
Design Flow - 600 GPM at 31' TDK
Construction - cast iron
Coagulant Aid Handling System (TK-3 & 4Z) - (PU-5 & 6Z)
The system consists of two 250 gallon tanks, each with agitators,
to put the powdered coagulant aid into solution. The coagulant aid in
the powder form is mixed with water through the use of an "Asperator"
43
-------
Coagulant Aid Handling System (continued)
feeder. This feed mechanism wets the particle before it enters the
250-gallon tank. The coagulant aid solution is pumped by one of
two (one is a spare) manually adjusted proportioning pumps to the
flash mix tank.
Tank Construction - carbon steel
Tank Size - 250 gallon
Pump Construction - steel
Pump Capacity - 12.4 GPH
Ferric Chloride Handling System (TK-6Z) - (PU-9 & 10Z)
The ferric chloride tank is sized at approximately 15,000 gallon
capacity. The tank was set at this capacity to insure enough space
should railway tank cars be used to transport ferric chloride to the
plant site in the future. The pumps to transfer the ferric chloride
to the flash mix tank are proportioning pumps and are manually adjust-
able. One pump is a spare.
Tank Construction - fiberglass
Tank Size - 12 ft. I.D., 18 ft. straight side
Pump Construction - PVC plastic
Pump Size - 0 to 15 GPH
Flocculator - Clarifier (TK-12Z)
From the laboratory studies it was determined that part, or all,
of the biologically inert solids were detrimental to the optimum per-
formance of a biological system. In addition, it was also necessary to
remove the inert solids for the following reasons:
(a) Minimize the difficulty in keeping the aeration tank
contents in suspension.
(b) Maximize oxygen transfer.
(c) Reduce the quantity of biologically inert solids in the
aeration tank and in the sludge aerobic digester which
is planned for the future.
(d) Reduce the suspended solids and turbidity in the
effluent.
Provisions are made at the flocculator-clarified to add caustic
to insure pH control in the biological system. This provision was made
44
-------
Flocculator - Clarifier (continued)
because of a "bulking" problem noted in the laboratory studies. The
following is a summary of the flocculator-elarifier design basis:
Design Flow - 0.8 MGD
Overflow Rate - 1000 GPD/ft.2
Flocculation Time - approximately 20 minutes
Construction - steel, above ground, pumped influent,
gravity effluent
Accessories - mechanical skimmer and sludge collector,
pH control
Phosphoric Acid Addition System (TK-6Z)
The phosphoric acid is provided to be added prior to the biologi-
cal process. The phosphoric acid is needed as a nutrient in the
biological system. The overall phosphorous requirement is 1 mg/1 per
every 100 mg/1 BOD5 entering the aeration basin. The amount of actual
phosphorous added will depend on the amount already in the waste stream
at that point.
A summary of the equipment and size of the tank is as follows:
Tank Construction - fiberglass
Tank Size - 8 ft. I.D., 14 ft. straight side
Diaphragm Pump Construction - 316 SS with Teflon diaphragm
Pump Capacity - 1.8 GPH
Ammonia Addition System (TK-28Z)
Ammonia is supplied to the system prior to the aeration basin as
a nutrient for biological growth. The ammonia supplies necessary nitro-
gen. The overall nitrogen needed in the system is 5mg/l per every 100
mg/lBOD5 entering the aeration basin. The actual amount of nitrogen
needed to be added depends on the amount already in the waste stream.
The ammonia is supplied to the system from a large storage tank
through an Ammoniator. The ammonia leaves the storage tank as a gas and
mixes with water in the Ammoniator, which forms ammonium hydroxide.
This is fed to the waste stream prior to an in line mixer before enter-
ing the aeration basin.
Biological Aeration System (TK-14Z & 15Z)
After leaving the primary clarifier and blending with the nutri-
ents, the waste flow passes through a flow splitter box that will
insure an equal distribution of flow between the two aeration tanks.
In the aeration basin the wastes will be mixed with an activated sludge
for approximately 370 minutes. The activated sludge consists of bacteria
45
-------
Biological Aeration System (continued)
and other micro-organisms within a biological floe. These organisms
utilize the organic content of the waste water as food and decompose
the organics to carbon dioxide and water. The oxygen needed is
supplied by a fixed surface aerator. The aerator in each tank was
sized based on the oxygen needed and the oxygen transfer characteris-
tics of the waste water.
A provision has been made in both aeration basins to monitor
dissolved oxygen and pH. These are both important since oxygen will
be needed at all times to accomplish the organic decomposition, and
a stable pH will be needed to prevent bulking.
Both aeration basins are equipped with spray nozzles to be used
to break foam that may be caused by aeration. The treatment system
effluent will be used for this service.
After leaving the aeration basin the waste water passes into a
secondary clarifier. Here the biological solids are settled out,
leaving a clear, low 6005 effluent. The settled solids are recircula-
ted back to the aeration tank, or are wasted, depending on the require-
ments of the system. The design of the system from the laboratory work
indicates that an MLSS level of 2500 mg/1 was optimum for that parti-
cular waste effluent at Pedricktown. To maintain the 2500 mg/1,
recycle sludge at the concentration of approximately 6700 mg/1 will be
recirculated at rates between 38.5 percent and 125 percent of the design
flow. This capacity was provided in order to have the capability of
handling larger MLSS levels in the aeration basin if it is desired in the
future.
The aeration tanks are sized to handle 10-20 percent above the design
flow without losing the efficiency as defined by the design. The
following is a summary of the design figures:
Basin
Design Flow - 0.8 MGD
Detention Time - 370 minutes with 71.5% recycle
10.6 hrs. for the forward flow only
Volume - approximately 178,000 gals, each
MLSS - approximately 2800 mg/1 (90% VSS)
Est. Oxygen Uptake - 70 mg/l/hr.
Design Temperature - 13° C.
BOD5 Removal Rate - 0.035 min. at 27° C.
Coefficient - 0.015 min.'1 at 13° C.
Dimensions - approximately 55 ft. diameter by
10 ft. SWD each
Construction - steel, above ground, baffled
Accessories - dissolved oxygen analyzers and re-
corders, froth sprays for foam
control, pH control, nutrient
addition
46
-------
Biological Aeration System (continued)
Mechanical Aerators
Energy Oxygen
BOD5 Removal
Oxygen Demand
Total Required
Endogenous Oxygen
Oxygen Demand
- approximately 4560 Ib./day at 27° C.,
907» load
- 0.916 02/lb. BODc removed
- 4,100 Ib./day
- 1.42 Ib. 02/lb. VSS destroyed
Sludge Destruction - 51 Ib./VSS destroyed/100 Ib. VSS ,
under aeration at 20° C.
Total Required - 875 Ib./day at 27° C., 90% load
Oxygen Transfer Conditions
a - 0.5
0 - 0.96
Design Temperature - 13° C.
Motor HP Required - 150 HP (at 85% overall energy
transfer efficiency)
Aerators per Basin - 75 HP - 2 speed
Secondary Biological Clarifiers (TK-16Z & 17Z)
The two secondary clarifiers are designed to operate at 53,000 gallon
capacity with an overflow rate of 565 GPD/ft2. The system was designed
to have an overflow rate such that the sludge would settle to approximately
a 1 percent consistency. The sludge recycle pumps are sized to return up
to 230 percent of the design flow. The pumps are variable speed so that
the full range, 0 to 230 percent, can be utilized without problems.
The whole biological system was of a flexible design so that the
effluent from either aeration basin could be directed to either second-
ary clarifier.
Each secondary clarifier is equipped with a skimmer to remove any
floating material that may accumulate on the surface of the clarifier.
The following is a summary of the design:
Flow
Overflow Rate-
Design
Design
Volume
Detention Time
Dimensions
Construction
Accessories
0.8 MGD
565 GPD/ft2
53,000 gallons each
190 minutes
approximately 30 ft. diameter by
10 ft. SWD
steel, above ground, gravity inflow
at periphery, gravity takeoff at
periphery
mechanical skimmers and tow-brow
sludge collectors
47
-------
Biological Sludge Freshening Tank (TK-13Z)
The purpose of this tank is to reoxygenate the activated sludge
wasted from the secondary clarifier. If the sludge was not reoxygenated
an anaerobic condition might exist causing the release of methane gas,
thus tending to float the sludge and making thickening difficult. The
air to be supplied will come from the packaged air compressor provided
with the sanitary waste treatment system.
The following is a summary of the design of this system:
Flow - 43,800 GPD sludge
Detention Time - 1 hour
Volume - 2,000 gallons
Dimensions - 7 ft. diameter by 6.5 ft. SWD
Air Required - 80 SCFM
Construction - steel, above ground, pumped inflow
from return sludge wastage, gravity
overflow to sludge thickener
Biological Sludge Thickener (TK-27Z)
It is anticipated that the normal biological clarified sludge from the
secondary clarifier will have a solids concentration between 0.5 and 1 per-
cent. The thickener should concentrate the sludge to 2 percent. The thick-
ening is accomplished by slowly agitating the sludge in the thickening
tank causing it to settle into a more compact mass. The discharge from
the underflow of the thickener can go directly to a centrifuge or a
sludge blending tank to be centrifuged with chemical sludge from the
primary clarifier. The supernatant liquid from the thickener passes
back to the equalization tank.
The following is a summary of the biological thickener design:
Flow - 43,800 GPD at 90% load
Overflow - 29,200 GPD
Design Overflow Rate - 174 GPD/ftz
Detention Time - 10.8 hours (liquid)
Volume - 18,900 gallons (liquid)
Dimensions - 20 ft. diameter by 14 ft. SWD
Underflow - 14,600 GPD (2,420 Ib. at 2% solids)
Construction - steel
Chemical Sludge Thickener (TK-18Z)
The purpose of this system is to thicken chemical sludge from the
primary clarifier prior to centrifuging. The underflow from the prim-
ary clarifier will be approximately 2.5 percent solids concentration. It is
expected that this will thicken to 8 percent solids. The thickening process
48
-------
Chemical Sludge Thickener (continued)
is accomplished by slowly agitating the waste solids. The underflow
from the chemical thickener is discharged to a sludge blending tank
prior to centrifuging. The system is flexible so that the chemical
sludge can be centrifuged separately, if necessary. The filtrate
from the thickener is returned to the equalization tank.
The following is a summary of the chemical thickener design:
Flow - 40,000 GPD
Overflow - 28,500 GPD
Design Overflow Rate - 160 GPD/ft2
Detention Time - 11.3 hours (liquid)
Volume - 18,800 gallons (liquid)
Dimensions - 20 ft. diameter by 14 ft. SWD
Underflow - 12,500 GPD (9,280 Ib. at 8% solids)
Construction - steel, above ground
Centrifuge (CE-lZ)
It is intended to use a solid bowl centrifuge for dewatering the
waste sludge. The centrifuge is designed on a hydraulic basis to
handle approximately 40,000 GPD of sludge.
Provision is made for adding a polyelectrolyte to the centrifuge
to aid in the dewatering of the sludge.
The centrifuge filtrate will be returned to the equalization tank
for further treatment.
The sludge cake (probably 15-25 percent solids) will be transported from
the production plant property and disposed of at a suitable sanitary
landfill site operated in accordance with the rules and regulations of
the New Jersey State Department of Health. It is estimated that approxi-
mately 23 tons of solids per day will be disposed of in this manner.
Lagoon
The treatment plant effluent will flow through a "polishing"
lagoon prior to discharge into the receiving stream. Some additional
BOD and solids removal should be obtained.
This lagoon will also normally receive the storm water run-off
from the operating area of the production plant. It is also anticipated
that spills may occur in the plant despite the most careful precau-
tions to prevent such incidents. This lagoon will be used to hold such
spills, if the treatment system cannot handle them. It should be em-
phasized that such a provision is a safety factor and that spills are
not anticipated to be a normal occurrence.
49
-------
Lagoon (continued)
The lagoon will provide detention of the design industrial waste
flow and a three-hour storm of one inch per hour that would have a
frequency of greater than once in 10 years, according to the records
of the U. S. Weather Bureau in Philadelphia.
The nominal dimensions of the lagoon are 200 feet by 250 feet
with a dry weather operating depth of 2 feet and a storm operating
depth of 4.25 feet.
Water Reuse
It is planned to reuse part of the water that will pass through
the treatment system. Investigations are now underway to determine what
additional treatment will be necessary to make the water acceptable for
reuse.
Metering, Sampling and Monitoring
A total carbon analyzer will be used on-stream to analyze the in-
fluent to the treatment system, the effluent from the primary clarifier,
and the effluent from the secondary clarifier. In addition, the waste
water treatment operators will routinely sample and analyze the waste
and solids at various locations throughout the system. The laboratory
facilities provided in the treatment area will provide for a routine
analysis of BOD, COD, TS, SS, VTS, VSS, pH, and SVI. Also, routine
microscopic observations of the aeration tank mixed liquor will be
made.
The treatment system has the facilities to meter the raw waste
flow sludge returned to the aeration basin and sludge wasted to the
thickening process. Other monitoring instruments are:
(1) pH control at the primary clarifier
(2) pH control at the aeration basins
(3) DO monitoring at the aeration basins
Continuous samplers have been provided on the raw waste stream
and effluent to get a good composite each day, so that the laboratory
tests mentioned above can be run.
50
-------
SECTION XI
OPERATION
Overall performance of the wastewater treatment system has been superior,
and to date, far exceeds design requirements. Hydraulic, organic, and
solids loadings in the raw, untreated wastewater have not reached those
design levels as given in Section 4. BOD5 and solids removals have con-
sistently averaged greater than 95 percent, with 95 to 99 percent removals
not uncommon.
This section discusses the performance of the system and the design and
mechanical problems encountered during system start-up and operation.
Actual operating data of individual unit operations and unit processes is
included.
For clarity of discussion, the system is divided into the following three
phases of treatment.
Primary Treatment,
Secondary Treatment,
Solids Handling
Primary Treatment
Primary Treatment comprises wastewater equalization, chemical coagulation,
solid flocculation and separation, pH control, and nutrient addition.
Pilot plant and laboratory studies indicated a need for good waste equal-
ization prior to primary and secondary treatment. The equalization sys-
tem provided (described previously) has performed satisfactorily in dam-
pening fluctuations in pH, solids loading, organic loading, and hydraulic
loading. The 950,000 gallon capacity system is operated at a two-thirds
full level and is allowed to fluctuate about this level for hydraulic
equalization. As a check on the blending and solids suspension effec-
tiveness of the 25 HP 30 RPM agitator associated with this system, pro-
bing (or sounding) studies were conducted to determine if build-up of
solid deposits were occurring. Investigation of the 90 foot diameter
tank bottom particularly in those areas most remote from the agitation
resulted in no solids build-up.
From the equalization tank, the wastewater is pumped on a controlled basis
to a two-compartment rapid mix tank where ferric chloride, caustic, and
coagulant aid are added. The wastewater flow is measured by a magnetic
flow meter and controlled as a function of the liquid level in the equal-
ization tank.
The flow measurement and control system have performed satisfactorily.
Considerable problems have been experienced with the rapid mix tank sys-
51
-------
Primary Treatment (continued)
tern. Initially, the ferric chloride was added at the bottom of the rapid
mix tank below the 1.5 HP rapid mixer. Overall agitation and blending of
the ferric chloride into the waste was adequate when related to detention
time; however, localized areas of concentrated ferric chloride occurred
in the rapid mix tank resulting in corrosion and failure of the tank
bottom. This problem was corrected by relocating the ferric chloride
addition to the top (water surface) of the rapid mix tank and by relocat-
ing a caustic neutralization addition to this same point. This method of
caustic addition, although manual, has been adequate to maintain a
satisfactory pH range.
Ferric chloride addition requirements have varied somewhat depending on
solids loadings. Optimum dosage conditions are determined by periodic
laboratory jar test procedures.
From the rapid mix tank, the wastewater gravity flows to the flocculator-
clarifier. Tables 11 through 14 show actual operating data for a four-
month period. Loadii gs and removals of suspended solids, COD, and BODc
are given for the primary treatment phase.
The suspended solids removal efficiency for the period was greater than
95 percent, resulting in a primary treatment effluent average concentra-
tion of 36 mg/1. Total solids removal for the period averaged 47 percent.
COD and BOD,, removals achieved in the primary system have been greater
than anticipated from the laboratory and pilot plant studies. COD and
BODc removals of 64 and 85 percent, respectively, were observed for the
reporting period.
These operating results were not achieved without problems. The floccu-
lator-clarifier was designed so that the wastewater entered from above
the tank rather than through the tank sidewall or bottom. The inlet pip-
ing terminated 18 inches directly above the flocculator compartment, allow-
ing the wastewater to gravity drop to the compartment. This resulted in
considerable turbulance and detriment to flocculation. To correct this
problem, a cone was installed to deflect the influent water and reduce
turbulance.
Problems were also experienced in removing floating solids. These pro-
blems were associated with the structural and mechanical design of the
skimming mechanism and with the erection of the flocculator-clarifier
tank shell.
The tank shell was erected without perfect alignment, thus resulting in
a slightly out-of-round tank. Subsequently, the out-of-round tank re-
sulted in scum flowing around the end of the skimmer arm at certain
areas of the tank. The problem has been partially solved by adjustments
to the wiper blades.
The skimming mechanism construction was of lightweight materials result-
ing in continuing maintenance attention for system operation.
52
-------
Table 11
Flocculator-Clarifier Performance Data
Month 1
Influent
Date
1
2
3
4
5
6
7
S
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
SS
mg/1
196
140
732
1,140
548
604
868
370
310
320
780
542
506
944
420
314
488
744
814
512
748
244
328
272
756
1,688
1,412
1,412
1,112
1,664
VSS
TOg/1
196
132
444
920
420
528
624
280
270
250
590
508
460
706
360
268
386
562
676
438
688
208
252
240
604
1,376
1,204
1,180
632
1,372
TS
mg/1
1,503
1,144
1,263
1,471
1,222
1,473
1,580
940
758
1,160
1,718
1,344
1,422
1,725
1,137
1,053
1,340
1,684
1,944
1,518
1,582
1,050
929
1,054
1,627
2,520
2,152
1,853
1,892
2,010
BOD
mg/1
162
67
35
75
134
114
140
115
44
164
228
173
193
220
148
51
273
140
183
272
255
157
108
147
94
107
114
99
29
16
COD
TOg/1
765
800
804
720
931
856
823
621
307
564
706
771
624
940
660
454
818
778
1,160
784
1,063
348
328
519
838
1,147
965
1,370
532
1,192
SS
mg/1
31
22
25
33
41
40
20
15
13
18
16
20
-
29
8
3
11
-
11
38
48
33
22
39
3
15
18
18
20
75
Effluent
VSS
mg/1
20
17
14
26
19
35
10
7
11
10
8
13
-
5
2
0
2
150
6
12
40
20
7
23
3
13
10
18
20
44
TS
mg/1
1,125
1,068
965
989
979
921
951
1,031
1,048
1,079
989
927
1,817
880
786
967
866
915
939
1,023
908
1,010
945
931
1,074
1,134
1,029
1,100
1,064
1,163
BOD
mg/1
128
93
14
20
71
34
63
66
12
66
124
127
112
140
104
65
99
39
104
130
91
61
77
77
33
51
23
10
16
-
COD
mg/1
109
171
113
68
156
262
269
145
121
124
392
210
382
268
143
100
138
215
180
108
291
202
105
115
62
76
74
82
83
67
-------
Table 12
Flocculator-Clarifier Performance Data
Month 2
Influent
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
SS
mg/1
1,530
870
908
800
732
450
750
920
928
1,400
998
240
1,126
808
1,002
2,444
1,556
840
1,212
1,220
988
510
2,180
1,990
1,530
1,296
1,220
1,088
860
1,556
3,270
VSS
mg/1
1,130
830
816
672
664
380
660
800
832
1,360
836
190
1,000
694
600
2,212
1,372
720
1,136
1,112
964
470
2,080
1,950
1,480
1,228
1,064
1,088
796
1,444
3,050
TS
TBg/1
1,894
2,005
1,724
1,572
1,493
1,241
1,323
2,141
2,136
2,430
2,124
2,022
1,824
1,537
5,333
3,308
2,756
2,187
1,859
1,788
1,601
1,520
3,048
2,791
2,044
2,008
1,788
1,733
1,723
2,145
4,368
BOD
mg/1
119
49
295
131
173
111
60
170
141
82
254
282
224
90
199
283
264
232
134
90
154
176
205
174
129
72
34
83
108
213
293
COD
mg/1
1,247
1,408
1,237
930
827
568
704
1,874
1,108
1,284
1,157
1,802
1,705
827
1,685
2,399
2,570
1,990
1,411
1,243
1,126
-
2,427
1,754
1,483
1,631
1,601
922
1,106
1,200
1,191
SS
mg/1
26
45
36
45
16
9
19
15
39
31
33
49
26
34
20
12
31
40
46
33
27
25
59
30
72
52
162
320
18
24
73
Effluent
VSS
mg/1
19
34
25
25
11
7
15
10
37
20
27
40
18
26
4
6
51
96
13
25
26
23
56
27
46
44
147
220
13
13
70
TS
ing /I
1,032
1,029
891
945
900
829
888
907
921
850
891
979
866
823
931
881
887
815
826
750
836
814
787
900
804
763
839
921
989
973
927
BOD
mg/1
22
17
52
38
49
17
11
17
42
55
110
184
99
24
31
70
68
70
65
50
17
12
5
13
7
4
2
13
13
39
99
COD
tng/1
69
115
171
140
154
107
15
77
93
126
234
336
222
91
97
81
224
170
181
126
87
-
92
83
71
114
122
109
168
282
490
-------
Table 13
Flocculator-Clarifier Performance Data
Month 3
Ln
Influent
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
SS
mg/1
2,520
1,490
1,440
1,280
1,000
1,730
1,970
-
1,600
1,930
1,600
1,310
1,070
1,090
990
1,020
850
180
136
376
248
768
2L6
472
260
332
700
2,012
1,665
1,000
600
VSS
mg/1
2,410
1,370
1,220
980
610
1,370
1,830
-
1,330
1,550
1,590
1,290
810
950
1,010
1,000
840
180
88
280
192
532
444
208
220
272
616
1,936
1,605
960
540
TS
mg/1
3,307
2,539
2,646
2,366
2,122
2,637
2,995
2,860
2,770
2,373
2,488
2,551
1,982
2,236
1,946
2,150
1,859
1,011
916
1,215
1,040
1,587
1,684
1,600
1,011
1,425
1,539
2,905
2,722
2,286
1,526
BOD
me/1
388
142
217
168
205
329
319
268
368
286
267
200
137
345
283
131
-
260
390
275
293
322
211
113
75
79
304
134
184
346
198
COD
mg/1
2,047
460
955
620
1,115
1,842
3,312
1,772
1,492
1,069
1,614
1,709
947
2,039
1,980
1,768
1,161
673
1,019
699
1,650
3,102
1,670
1,258
762
767
1,541
1..134
3,363
1,383
1,080
SS
mg/1
58
2
20
35
20
112
123
-
33
77
25
22
29
44
93
32
14
80
21
21
55
36
34
21
28
20
20
38
18
35
37
Effluent
VSS
mg/1
57
1
9
33
13
76
91
-
6
47
25
19
8
53
87
29
13
54
12
8
47
20
23
12
14
10
14
38
18
22
27
TS
mg/1
1,032
1,021
990
1,127
995
830
1,087
1,105
1,089
938
896
887
809
916
899
897
941
920
744
830
846
958
950
871
803
934
949
971
917
988
929
BOD
mg/1
56
41
74
31
59
67
109
98
137
109
105
93
56
80
81
90
87
60
65
50
69
127
86
23
15
7
80
87
81
204
158
COD
mg/1
428
460
193
225
295
480
261
288
271
237
226
191
135
142
193
187
100
82
136
92
194
176
153
93
48
141
95
163
140
339
305
-------
Table 14
Flocculator-Clarifier Performance Data
Month 4
Ui
Influent
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
SS
mg/1
524
418
1,090
930
1,460
2,440
2,370
1,760
2,110
2,490
440
260
1,420
1,320
1,120
788
1,180
510
520
300
380
270
630
700
872
1,068
1,960
720
vss
mfiA
456
390
1,060
860
1,390
2,330
2,230
1,430
1,870
2,410
400
200
1,400
1,300
1,065
760
1,080
420
520
-
330
260
500
620
800
1,000
1,520
680
TS
tng/1
1,545
1,534
2,361
2,649
2,648
3,620
3,412
2,702
2,550
2,275
2,015
1,995
2,679
2,379
1,922
1,698
2,246
1,813
1,553
1,452
1,465
1,073
1,213
1,876
1,797
2,025
3,719
1,687
BOD
me 11
140
178
202
284
277
257
178
135
193
191
334
279
321
252
155
310
220
188
228
213
154
63
102
82
393
236
237
167
COD
mg/1
1,140
1,131
1,380
1,645
1,308
1,740
2,048
976
972
987
967
2,000
1,785
1,521
1,574
1,532
1,765
1,372
1,600
1,042
990
510
980
1,130
1,300
1,257
1,390
1,410
SS
mg/1
18
13
20
20
37
23
20
73
32
63
31
31
22
65
4
52
49
12
22
22
25
18
23
35
26
48
65
10
Effluent
VSS
mg/1
6
12
19
17
33
20
20
54
15
55
25
29
22
56
3
46
37
12
20
21
14
15
12
32
25
39
33
7
TS
mg/1
1,010
926
974
1,007
1,072
969
992
930
907
929
961
1,028
993
918
851
839
951
901
945
930
887
-
774
850
910
924
884
801
BOD
mg/1
89
59
145
246
227
155
125
84
86
95
219
208
158
138
67
73
106
53
92
111
92
53
28
103
282
254
191
106
COD
mg/1
212
139
200
365
381
255
228
208
154
217
348
402
323
310
181
160
207
122
184
221
186
91
147
163
500
416
363
240
-------
Secondary Treatment
Secondary treatment comprises biological oxidation via a completely mixed
activated sludge process followed by clarification and sludge recycle.
Initial start-up of the biological system was quite smooth. When plant
production operations started, the wastewaters were stored in the equal-
ization tank until sufficient volumes were available to fill and supply
feed to the biological aeration system. The aeration tank was filled with
wastewater and aerators started. Activated sludge from two nearby muni-
cipal sewage treatment plants was introduced to the system as seed. App-
roximately 60,000 gallons ware used. The activated sludge was added dir-
ectly to the secondary clarifiers and fed immediately to the aeration
system for oxygen via the sludge recycle sy-stem. The sludge added re-
sulted in an aeration tank mixed liquor volatile solids concentration of
600 mg/1.
During initial start-up of production operations the wastewaters were
extremely variable in volume and composition. Supplementary feed (corn
sugar) was added to the biological system during this period.
To date, the organic loading to the wastewater treatment system has not
reached design levels. This has resulted in the biological system being
operated in the extended aeration range as can be seen from the data in
Tables 15 through 18. These tables show calculated levels of the feed to
microorganism ratio "and the BOD removal rate as discussed in section VII.
No meaningful correlations of this data with pilot plant conditions can
be made while the system is operated in the extended aeration range.
The two-speed 75 HP aerators have been more than adequate to meet oxygen
requirements. Only one train of the dual train secondary system was op-
erated through the reporting period. One aerator on low speed has been
used. Actual oxygen usage has been approximately 1.2 pound/pound of BOD
removed. The average usage for Month 1 and Month 2 were 1.01 and 1.3
pound/pound of BOD removed, respectively. This compares favorably with
conventional extended aeration systems.
The sludge return system and magnetic flow meters have performed quite
satisfactorily but hydraulic problems on the discharge piping of the
system have developed. The return sludge from both clarifiers is mixed
in a common header and then the flow is split between the two aeration
tanks. A side stream from this header allows sludge to be wasted to the
sludge freshening tank. The return piping to the aeration tanks was
sized large enough to allow maximum sludge flow back to one aeration
tank in case one aerator was out of service. However, the large piping
did not exert enough back pressure to allow sludge to be wasted under
normal conditions unless the control valves were almost closed. This
problem was corrected by inserting restricting orifices in the lines to
the aeration tanks.
57
-------
Secondary Treatment (continued)
Tables 19 through 22 show recycle sludge solids levels, secondary clari-
fier influent and effluent conditions, and effluent BOD,, levels.
Sludge recycle concentration for the period averaged 5,160 mg/1 suspended
solids of approximately 82 percent volatile content. Secondary clarifier
suspended solids removal averaged 99 percent resulting in an average eff-
luent concentration of 20 mg/1 and an overall suspended solids removal
efficiency of 98 percent for the complete treatment system. The BOD re-
moval for the complete treatment system exceeded 98 percent resulting in
an average effluent concentration of 2.4 mg/1. Ammonia nitrogen and phos-
phate residuals average 0.65mg/l and 0.29 mg/1 respectively.
Solids Handling
The solids handling system was designed to handle two types of sludge; bio-
logical sludge and inert or chemical sludge. The chemical sludge is from
two sources, the primary clarifier and the preclarifier in the process
area. This sludge is composed primarily of PVC solids but also contains
iron floe from the water treatment plant. The biological sludge is waste
activated sludge from the secondary system.
The chemical sludge thickener has performed satifactorily. This tank was
designed for both thickening and sludge storage. The only problems ex-
perienced with the thickener occurred when the sludge became so concentra-
ted that the unit over-torqued. This usually happened when production was
shut down and there was little flow through the system. The thickener can
thicken up to 13 percent solids before problems occur.
The sludge concentration from the primary clarifier runs about 2 percent
solids which compares with the 2.5 percent used for design. The sludge
from the preclarifier is quite variable and may range from almost water
up to about 25 percent solids. Normal operation is to thicken to approxi-
mately 8 percent solids. From the thickeners, the sludge is pumped to
the sludge blend tank in order to insure a uniform feed to the centrifuge.
Throughout the brief period during which the biological sludge thickener
was in service, performance was excellent. The sludge could be thickened
to about 7 percent solids, which was greater than expected.
No problems were experienced with the centrifuge on initial start-up.
Later a problem did develop with iron fines which were not being removed
by the centrifuge. The centrate from the centrifuge was recycled to the
head of the treatment system thereby allowing this iron floe to be re-
moved again in the flocculator-clarifier. Subsequently, the fines continu-
ed to build up in the system. This necessitated the addition of a coagu-
lant aid addition system which is shown on the flow sheet in Section X.
Typical operation of the centrifuge with a feed sludge of 8 percent solids
resulted in a 25 to 30 percent solids cake and a centrate of .1 percent or
less. Average daily wet sludge production was 16,716 pounds and 25,267
pounds for Month 1 and 3 respectively.
58
-------
Table 15
Aeration Tank Performance Data
Month 1
VO
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Temp.
°C
19
19
19
17
16
16
17
16
16
18
19
20
18
18
18
14
14
15
17
17
18
16
14
11
13
13
13
14
16
Load
LiZSt
"•™^^™"— ^
.058
.047
.006
.003
.030
.014
.024
.020
.005
.029
.044
.037
.030
.033
.021
.016
.024
.010
.026
.033
.020
.012
.015
.015
.005
.009
.006
.002
.004
Det.Time
Min.
1281
1364
1203
1195
1267
1050
1413
2000
1568
1167
1152
1116
1123
1290
1568
1369
1089
997
1267
1066
1323
2132
1435
2011
2599
2373
2373
2760
2561
Rate
Mln-1
.0617
.0265
.0224
.0326
.1113
.0314
.0439
.0655
.0045
.0180
.2144
.2267
.1986
.1078
.1320
.0467
.0445
.0381
.0813
.0600
.0680
.0091
.0529
.0378
.0123
.0103
.0190
.0069
.0038
Loading
#BOD/#VSS/Day
.1331
.1040
.0143
.0064
.0708
.0361
.0533
.0388
.0095
.0684
.1088
.0926
.0754
.0768
.0452
.0351
.0609
.0253
.0614
.0828
.0450
.0207
.0337
.0278
.0080
.0115
.0075
.0026
.0045
% Removed
99
97
96
97
99
97
98
99
87
95
100
100
100
99
100
98
98
97
99
98
99
95
99
99
97
96
98
95
91
Rate 20°C
Min-1
.0655
.0281
.0238
.0391
.1415
.0399
.0526
.0833
.0057
.0203
.2277
.2267
.224
.1216
.1783
.067
.0638
.0515
.0974
.0719
.0767
.0116
.0759
.0649
.01873
.0157
.0289
.0099
.0048
-------
Table 16
Aeration Tank Performance Data
Month 2
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
Temp.
-°C
15
16
16
15
13
10
8
9
12
13
13
12
11
12
12
15
15
15
16
Load
Li/S1
.004
.004
.012
.009
.004
.003
.002
.005
.012
.016
.030
.048
.024
.005
.009
.022
.030
.022
.018
Det.Time
Min.
1119
1106
1156
1348
1641
2094
2094
1745
1477
1343
1561
1762
1762
1864
1703
1219
904
920
1391
Rate Loading
Min-1 #BOD/#VSS/Dav
.0384
.0145
.0216
.0556
.0201
.0158
.0100
.0189
.0278
.0811
.4103
.2082
.1118
.0123
.0085
.0183
.0139
.0370
.0227
.0102
.0091
.0286
.0187
.0067
.0058
.0040
.0102
.0246
.0366
.0634
.0970
.0486
.0101
.0174
.0495
.0785
.0604
.0381
% Removed
98
94
96
99
97
97
95
97
98
99
100
100
99
96
94
96
93
97
97
Rate 20 °C
Min-1
.0519
.0184
.0275
.0751
.0306
.0288
.0206
.0366
.0449
.1236
.2137
.3369
.1690
.0200
.0138
.0247
.0188
.0499
.0288
-------
Table 17
Aeration Tank Performance Data
Month 3
Date
1
2
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
30
31
Temp.
°C
12
14
18
20
16
16
16
17
18
21
18
12
15
17
13
15
15
14
15
17
19
21
18
19
18
12
16
18
13
Load
Li/S-i
.018
.017
.013
.035
.031
.042
.040
.058
.031
.037
.044
.029
.049
.038
.038
.037
.034
.048
.071
.065
.088
.068
.026
.009
.007
.054
.046
.098
.053
Det.Time
Min.
1411
1081
663
513
653
763
757
756
779
736
744
744
650
672
699
694
695
672
695
707
769
836
842
817
654
636
542
665
1085
Rate
Min-1
.0191
.0180
.0141
.0236
.1011
.0940
.0310
.1195
.0687
.0343
.0195
.0094
.0121
.0136
.0115
.0111
.0093
.0093
.0066
.0181
.0813
.0502
.0097
.0110
.0038
.0613
.0624
.1007
.0476
Loading
#BOD/#VSS/Dav
.0257
.0299
.0381
.1358
.0918
.1119
.1065
.1553
.0806
.1003
.1200
.0808
.1502
.1213
.1237
.1212
.1090
.1394
.1699
.1561
.1998
.1438
.0624
.0232
.0175
.1549
.5102
.2709
.1018
Removed
96
95
90
92
99
99
96
99
98
96
94
87
89
90
89
89
87
86
82
93
98
98
89
90
71
97
97
99
98
Rate 20°C
Min-1
.0276
.0259
.0159
.0236
.1286
.1195
.0395
.1431
.0775
.0323
.0220
.0152
.0164
.0163
.0174
.0150
.0126
.0133
.0089
.0217
.0863
.0473
.0110
.0117
.0042
.0993
.0794
.1136
.0726
-------
Table 18
Aeration Tank Performance Data
Month 4
NJ
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Temp.
°C
12
8
13
15
17
18
17
18
15
14
16
18
21
17
17
18
19
23
23
24
19
19
19
15
Load
LI/S!
.020
.013
.031
.075
.046
.031
.018
.026
.017
.018
.100
.077
.043
.028
.015
.020
.030
.019
.030
.035
.039
.024
.015
.040
Det.Time
Min.
1037
827
698
806
1095
1135
1091
1105
1064
1049
1059
1044
666
875
871
893
876
855
863
1345
1238
1179
709
613
Rate
Min-1
.0308
.0218
.0851
.2022
.1286
.0674
.0247
.0557
.0260
.0292
.0508
.0488
.1170
.0778
.0373
.0806
.0594
.0608
.1511
.1172
.0363
.0741
.0150
.0783
Loading
#BOD/#VSS/Day
.0710
.0501
.1366
.2325
.1208
.0784
.0451
.0682
.0451
.0485
.2174
.1359
.1232
.0740
.0397
.0526
.0778
.0507
.0839
.0777
.0870
.0558
.0459
.1703
% Removed
97
95
98
99
99
99
96
98
97
97
98
98
99
99
97
99
98
98
99
99
98
99
91
98
Rate 20°C
Min-1
.0499
.0449
.1297
.2732
.1541
.0760
.0296
.0628
.0351
.0420
.0646
.0551
.1102
.0931
.0447
.0884
.0630
.0507
.1317
.0921
.0386
.0787
.0160
.1058
-------
Table 19
Secondary Treatment Performance Data
Month
OJ
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Recycle
Sludge
SS TS
mg/1 me/1
1216
2216
2356
2630
3180
2410
3560
2430
2700
2870
3810
4490
4960
5500
4770
3980
4890
4640
5050
5240
5620
5160
3940
3840
3040
1410
1660
1940
2642
2828
3254
3300
3509
3239
3912
3333
3035
3719
4506
4608
5055
5296
4566
4483
4451
5032
5423
5356
6045
5764
4546
4707
3912
2077
2338
7100
2181
Secondary Clarifier
SS
tne/1
908
1132
1612
1670
1520
1310
1740
1480
1890
1610
2050
2090
2110
2440
2650
2400
2610
3050
2610
2950
2920
2680
2850
2540
2890
3350
3180
3470
3500
4010
Influent
VSS
me/1
756
832
1284
1360
1130
1060
1210
1200
1700
1200
1710
1750
1670
1840
2110
2000
2120
2350
1920
2180
2080
1770
2270
1920
2310
3744
2510
2840
2810
3230
Secondary Clarifier
Effluent
TS
ma/1
2091
2077
2126
2087
2140
2143
2307
2380
2347
2517
2924
2544
2708
2856
2912
3039
2682
2680
3112
3274
3428
3511
3575
3468
3749
4128
3992
3801
3813
4071
SS
me/1
14
15
6
14
18
5
15
9
12
15
8
9
7
27
11
7
8
13
16
16
27
13
20
23
10
16
16
10
-
34
VSS
me/1
6
12
6
14
18
5
5
5
8
2
4
5
4
8
7
2
3
9
1
4
22
12
7
15
5
6
14
10
-
23
TS
me/1
997
1010
976
945
945
928
882
954
969
1003
966
885
891
798
810
851
802
800
816
877
892
885
898
881
924
.982
1021
1010
-
1051
Effluent
BOD
me/1
1.3
2.4
.35
.33
.4
1.2
1.2
0.5
1.5
2.8
0.6
0.6
0.7
.8
0.7
1.0
2.0
1.0
0.7
2.0
1.0
3.0
1.0
1.0
1.0
2.0
.35
.18
1.3
-------
Table 20
Secondary Treatment Performance Data
Jlonth 2
ON
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Recycle
Sludge
SS TS
mg/1 tng/1
4570
6420
5560
5870
5730
4200
5000
4240
3600
3540
3460
3540
3360
3280
3520
4800
3980
980
468
704
5250
4870
5310
3960
.3510
3140
2840
3810
4680
7770
4820
6378
6630
6566
5932
5275.
5335
4732
4269
4273
3929
4039
3706
3854
4120
4164
4284
2596
1133
1369
5977
5596
6372
4798
4213
3765
4176
4560
5515
8591
Secondary Clarifier
SS
mg/1
3640
2700
2680
2510
2390
2010
1920
1820
1920
1940
1590
1900
2300
2100
1980
1840
1180
1960
2850
3310
2890
3000
2810
2580
2230
2660
2710
2530
2300
1390
2580
Influent
VSS
mg/1
3080
2190
2190
2010
2170
1840
1750
1330
1650
1620
1440
1690
1790
1850
1470
1690
1140
1790
2250
2760
2530
2630
2390
2240
1840
2240
2290
2180
1950
1160
2310
TS
mg/1
3871
3475
3206
3123
2993
2762
2635
2500
2574
2652
2703
2734
3779
2362
2763
2685
2220
2649
3273
3835
3546
3597
3424
3176
3047
3301
3167
3040
3203
3252
3326
Secondary Clarifier
SS
mg/1
12
27
23
109
16
5
16
9
10
18
8
14
15
13
19
11
20
11
42
-
10
11
5
9
7
21
0
48
22
37
7
Effluent
VSS
mg/1
9
8
23
10
6
4
7
6
4
13
6
9
9
8
4
9
11
5
19
_
8
10
5
8
1
12
0
36
17
26
12
TS
mg/1
1086
986
919
881
904
828
830
869
842
843
837
825
851
823
827
835
826
750
745
694
797
780
766
775
774
746
733
770
767
820
Effluent
BOD
mg/1
0.3
1.0
1.8
0.6
0.2
0,
0,
0.2
1.0
0.4
0.5
0.4
0.8
,0
.0
.0
.0
,0
,0
,0
.0
1.0
2.0
1.0
0.2
0.9
0.9
1.1
0.5
2.2
-------
Table 21
Secondary Treatment Performance Data
Month 3
01
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Recycle
Sludge
SS TS
tng/1 me/1
9780
11,880
8430
11,280
9330
5650
5720
8110
7380
6150
7600
4600
2740
4180
4450
3280
3370
2930
7640
9020
8280
6500
4430
5300
5600
4840
6560
10,010
10,760
7450
10,284
12,290
8812
11,517
9122
5040
6715
7200
8930
6320
6742
7862
5107
3800
5348
5055
3989
4097
3580
8056
10,323
8613
8160
5350
6118
6590
6271
7250
10,657
11,985
8075
Secondary Clarifier
SS
me/1
2470
2060
2260
1970
1470
2090
2180
-
2380
2250
2170
1660
1670
1250
1530
1750
1520
1450
1480
1500
1420
1810
1440
1610
1490
1620
1630
1710
1910
1880
2390
Influent
VSS
me/1
2220
1830
1860
1770
1220
1610
1840
-
1680
2500
2050
1500
1340
1180
1430
1500
1490
1140
1000
610
900
1190
1030
630
1140
880
1170
1540
1720
1630
2060
Secondary Clarifier
Effluent
TS
ma/1
3206
3088
3099
2831
2613
2680
2707
2853
3024
3377
2920
2662
2601
2206
2261
2342
2311
2221
2136
2122
1880
2274
2384
2436
2294
2308
2433
2601
2772
2801
3111
SS
mK/1
20
5
20
28
18
32
29
-
3
56
13
24
41
60
20
44
54
41
64
26
8
35
23
11
20
15
20
20
5
17
19
VSS
me/1
23
3
11
27
14
4
23
-
0
28
13
18
14
30
2
40
42
40
40
16
6
28
15
8
10
9
14
20
5
11
10
TS
me/1
865
392
1011
1012
997
601
938
1034
971
930
904
942
869
898
839
894
892
866
824
778
783
800
906
924
765
883
891
941
870
^902
826
Effluent
BOD
mg/1
1.8
1.9
2.6
3.1
4.5
1.2
1.3
4.0
1.6
2.0
4.0
6.0
7.0
9.0
8
.10
10
8
9
9
5
2
2.1
2.7
1.6
2.2
1.9
2.4
3.0
3.2
3.2
-------
Table 22
Secondary Treatment Performance Data
Month 4
ON
ON
Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Recycle
Sludge
SS TS
mg/1 me/1
7010
3810
4400
6100
6790
6590
6690
7320
7270
7070
8040
14,890
10,240
11,730
9880
10,570
9040
8230
6040
5710
3070
3030
5670
9090
7710
8630
8770
8850
7745
3280
5015
7177
7593
7340
7633
8034
1111
8006
8788
16,076
11,304
12,298
11,969
Secondary Clarifier
SS
mg/1
2060
2320
2480
2300
2770
2810
2620
2480
3020
2760
1660
2180
3100
3390
3140
2550
2590
1980
2030
1630
1460
1340
1440
1690
2300
2580
3000
2760
Influent
VSS
ma/1
1740
2050
2190
1890
2470
2510
2390
2460
2580
2690
1370
2110
2770
3070
2790
2240
2240
1760
1830
1530
1230
1160
1240
1420
2070
2290
2460
2590
TS
ma/1
3215
3182
3208
3465
3720
3741
3846
3670
3531
3767
2821
3563
4151
4090
-
-
-
-
-
-
-
2566
-
-
-
-
-
-
Secondary Clarifier
SS
me/1
14
22
40
16
12
5
5
23
20
16
13
20
5
27
17
41
39
19
15
16
12
13
10
20
30
26
56
3
Effluent
VSS
TDK/1
4
19
39
15
10
2
0
5
9
11
2
12
5
26
17
39
30
18
14
16
3
12
4
18
14
20
26
2
TS
tng/l
873
937
934
911
921
956
973
890
825
816
851
919
896
887
862
960
857
908
839
880
871
875
825
751
854
819
826
763
Effluent
BOD
mg/1
2.7
3.1
2.4
,5
,6
1,
1,
2
2
3
3
3
4
4
2
2
2
1
2
1
0.7
0.7
2
0.6
2.4
7.1
9.0
9.2
4.2
4.9
-------
SECTION XII
WASTEWATER RECYCLE AND REUSE
The preservation of our natural resources through recycle and reuse pro-
cesses is becoming evermore common throughout industry today. Although
recycle and multiple reuse of cooling waters has long been practiced,
only during the past few years has such attention been given to the re-
cycle and reuse of wastewater streams.
Recycle and reuse of the secondary treated PVC production plant wastewaters
from the Pedricktown plant has been evaluated. The planned recycle system
including actual pilot operation data is presented and discussed in this
section.
The raw water supply for the plant is from underground wells. Water is
pumped from two separate underground aquifiers and treated according to
its ultimate use. Two separate but identical raw water treatment systems
were installed with the original plant. One of these systems has been
utilized for evaluation of wastewater recycle.
The quality of the secondary treated wastewater has been high, as can be
seen from Tables 19 through 22 of Section XI. For the past several months
a recycle evaluation program has been underway in which 100 gallons per
minute of secondary treated effluent has been recycled to the raw well
water treatment system for further treatment. Tables 23 and 24 show
typical water quality after treatment in the well water system. This water
is of acceptable quality for reuse as service and cooling water.
To date recycle has been accomplished through a temporary system of pumps
and firehoses. Plans are now underway to install a permanent recycle
system for further evaluation of wastewater recycle and reuse.
The secondary treated effluent will gravity flow to a 1,500 gallon surge
tank in which chlorine is added for bacteria control. From the surge
tank the chlorinated wastewater will be pumped to the existing water
treatment system. The existing water treatment system, supplied by Los
Angeles Water Treatment Company, consists of an aeration tower, followed
by a reaction-precipitation-sedimentation tank, followed by an anthracite
coal filter. From the water treatment system, the treated waters will
gravity flow to the treated water reservoir. These waters will then be
used for cooling purposes, service water, and fire water.
67
-------
Table 23
Recycle Water Quality
Residual Dissolved
Iron Chlorine Turbidity Solids
£H mg/1 mg/1 JTU mg/1
79 8.0 .25 .01 4 1,050
89 8.15 .55 .01 11
98 7.8 .35 .03 10 1,200
98 8.25 .28 Nil 8 1,200
54 8.5 .42 .01 25 1,350
121 7.8 .63 Nil 20 1,300
90 7.65 .35 Nil 25 1,350
60 7.45 .1 .05 10 1,300
203 8.0 .9 .03 25 1,150
106 8.25 .23 .03 48 1,100
70 8.3 .45 .15 30 1,200
145 8.0 .14 .04 40 950
157 7.8 .1 .05 10
104 8.15 0.4 .06 21 1,120
70 8.05 .47 .01 35 1,125
79 7.35 0.48 .02 25 990
100 7.95 0.95 .07 43 970
110 7.95 1.2 0.10 43 1,030
114 8.1 0.06 0.12 38 1,100
74 7.55 0.76 0.11 26 1,090
101 8.2 0.94 0.08 26 1,120
93 7.25 0.60 1.1 36 1,110
85 7.5 .04 1.38 37 1,290
99 7.6 .15 .14 24 1,370
80 8.1 .20 .08 13 1,400
44 7.8 0.45 0.01 0 880
37 7.15 0.32 0.01 1 860
22 7.8 .02 <.01 4 850
33 7.81 .04 <.01 11 820
27 7.7 .05 <.01 16 800
68
-------
Table 24
Recycle Water Quality
COD
mg/1
125
83
55
74
57
75
79
129
106
225
119
-
104
19
35
-
38
43
37
24
34
19
21
25
34
-
26
-
25
42
2H
7.5
8.0
8.02
7.6
8.1
7.8
8.0
8.1
8.0
8.2
8.4
7.2
8.15
7.4
8.1
7.3
7.2
7.4
7.5
8.1
8.25
8.15
8.1
8.25
8.1
8.05
7.4
7.5
7.5
7.7
Iron
mg/1
.05
.05
.031
.02
.70
.05
.4
.02
.8
.3
.023
.05
.4
.03
.04
.03
.05
.01
.03
.01
.05
.05
.03
.05
.05
.32
.03
.10
.18
.34
Residual
Chlorine
mg/1
.05
<.01
.02
.01
-
.07
.05
<.o
.03
<.01
<.01
.09
.06
.15
.04
.01
.25
.02
.01
.01
.01
.01
.01
.05
-
.01
.01
.01
.02
.01
Turbidity
JTU
28
12
21
20
19
18
25
20
25
25
10
11
21
0
5
3
0
0
0
0
9
0
0
5
3
11
10
12
0
0
Dissolved
Solids
910
1,000
990
930
910
990
900
950
900
1,000
1,200
850
1,120
900
900
1,000
950
1,000
900
1,000
1,050
1,000
1,000
1,025
1,000
880
970
900
905
875
69
-------
SECTION XIII
ABBREVIATIONS
PVC Poly vinyl chloride
BOD Biochemical Oxygen Demand
BODg Five-day biochemical oxygen demand
C Temperature - degrees centigrade
COD Chemical Oxygen Demand
TC Total Carbon
TS Total Solids
VTS Volatile Total Solids
SS Suspended Solids
VSS Volatile Suspended Solids
JTU Jackson Turbidity Units
RPM Revolutions Per Minute
mg/1 milligrams per liter
PSIG Pressure - pounds per square in guage
GPD/ft Gallons per day per square foot
DO Dissolved oxygen
ml milliliters
MLSS Mixed Liquor Suspended Solids
MLVSS Mixed Liquor Volatile Suspended Solids
SVI Sludge Volume Index
MGD million gallons per day
GPM gallons per minute
hr hour
SWD side water depth
TDH total dynamic head
dia diameter
HP horsepower
I.D. Inside Diameter
SCFM Standard Cubic Feet per Minute
Ib s pound s
% percent
71
-------
SECTION XIV
REFERENCES
1. Albright, L.F., "Vinyl Chloride Polymerization by Emulsion,
Bulk, and Solution Processes". Chemical Engineering, 74, 7, 85
(1967)
2. Barr, J.T., "Vinyl and Vinyladiene Chlorine Polymers on
Copolymers", in "Manufacture of Plastics: Vol. 7", Reinhold
Publishing Corp., New York (1964)
3. Shreve, N., "Chemical Process Industries" McGraw-Hill, New
York (1967)
4. "Polyvinyl Chloride". Private report by Stanford Research
Institute, (June, 1966)
5. New Jersey State Department of Health Regulations Concerning
Treatment of Waste Water, Domestic and Industrial, Separately
or in Combination, Discharged into the Waters of the Delaware
River Basin, filed with the Secretary of State, October 17, 1967.
6. Product of Calgon Corp., Pittsburgh, Pennsylvania
7. Product of Nalco Chemical Co., Chicago, Illinois
8. Weston, R.F., "Design of Sludge Reaeration Activated Sludge
Systems", Journ. W.P.C.F. 33, 7, 748 (1961)
9. Weston, R.F. and Stack, V.T., "Prediction of the Performance
of Completely Mixed Biological Systems from Batch Data".
Presented at Manhatten College Biological Waste Treatment
Conference (April, 1960)
10. Bhatla, M.N., Stack, V.T., and Weston, R.F., Journ. W.P.C.F.
4, (1966)
11. Eckenfelder, W.W., and O'Conner, D.J., "Biological Waste
Treatment". Pargaman Press, New York (1961)
12. Eckenfelder, W.W., "Industrial Water Pollution Control,"
McGraw Hill, Inc., New York (1966)
73
-------
1
5
Accession Number
2
Subject Field Si Croup
05D
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
Organization
B. F. Goodrich Chemical Company
Environmental Control Engineering
Title
Wastewater Treatment Facilities for a Polyvinyl Chloride Production Plant
10
Authors)
B. F. Goodrich Chemical Co.
Environmental Control Dept.
16
Project Designation
EPA, ORM, Grant f 12020 DJI 6/71
2] Note
22
Citation
Descriptors (Starred First)
25
Identifiers (Starred First)
Industrial wastes, polyvinyl chloride, activated sludge, process monitoring
271 Abstract B> F> Goodrich Chemical Company has completed construction and has begun
operation of a new polyvinyl chloride (PVC) production plant that includes emulsion,
suspension, and bulk polymerization processes. The wastewater treatment system for
this plant was designed to meet the stringent discharge requirements of both the
State of New Jersey and the Delaware River Basin Commission. The wastewater treatment
system consists of a primary-secondary completely mixed activated sludge process including
equalization, flocculation, clarification, mechanical aeration, nutrient addition,
sludge thickening and centrifugation, and automatic process monitoring. Although the
Company operates several PVC production plants in the United States, none of these
plants could be considered to be a duplicate of the proposed production plant. Therefore,
it was necessary to simulate the anticipated production plant wastes by selective sampling
and to conduct pilot plant treatment studies. This report presents summarized results
of the laboratory and pilot plant studies and a complete and detailed description of the
full-scale wastewater treatment system as constructed. Actual operating data of the
system is included and supplemented by discussion of individual unit operations and unit
process performance. Evaluation of a full-scale wastewater recycle and reuse system is
included. This report was submitted in fulfillment of Project Number 12020 DJI under
the sponsorship of the Office of Office of Research and Monitoring, Environmental
Protection Agency.
Abstractor
Institution
WR:102 (REV. JULY 19691
WRsrc
SEND TO: WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON. D C. 20240
* SPO: 1989-359-339
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