United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Cincinnati OH 45268
EPA-600 2-79-110
July 1979
Research and Development
&EPA
Processing Chrome
Tannery Effluent to
Meet Best Available
Treatment Standards
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution-sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
t on Service, Springfield, Virginia 22161.
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EPA-600/2-79-110
July 1979
PROCESSING CHROME TANNERY EFFLUENT TO MEET
BEST AVAILABLE TREATMENT STANDARDS
by
Lawrence K. Barber
A. C. Lawrence Leather Co., Inc.
Winchester, New Hampshire 03470
Ernest R. Ramirez
Swift Environmental Systems
Chicago, Illinois 60680
William L. Zemaitis
Envirobic Systems
New York, New York 10001
Grant No. S 804504
Project Officer
Jack L. Witherow
Food and Wood Products Branch
Industrial Environmental Research Laboratory
Corvallis, Oregon 97330
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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DISCLAIMER
This report has been reviewed by the Industrial Environmental Research
Laboratory, U. 3. Environmental Protection Agency, and approved for publica-
tion. Approval does not signify that the contents necessarily reflect the
views and policies of the U. 3. Environmental Protection Agency, nor does men-
tion of trade names or commercial products constitute endorsement or recommen-
dation for use.
ii
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FOREWORD
When energy and material resources are extracted, processed, converted,
and used, the related pollutional impacts on our environment and even on our
health often require that new and increasingly more efficient pollution con-
trol methods be used. The Industrial Environmental Research Laboratory-
Cincinnati (lERL-Ci) assists in developing and demonstrating new and improved
methodologies that will meet these needs both efficiently and economically.
The A. C. Lawrence Co. has demonstrated a highly efficient wastewater
treatment system at their chrome tannery in Winchester, N. H. The system
uses flow equalization, primary treatment by chemical addition and air
floation, and secondary treatment in an oxidation ditch. Removal of both
carbonaceous and nitrogenous materials was. accomplished. This study will be
of great interest to the entire leather tanning industry. The Food and Wood
Products Branch, lERL-Ci, may be contacted for further information on the
subject.
David G. Stephan
Director
Industrial Environmental Research Laboratory
Cincinnati
iii
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ABSTRACT
To satisfy stream discharge requirements at its Winchester, N. H.,
chrome tan shearling tannery, the A. G. Lawrence Leather Co., Inc. selected
primary and secondary systems that are unique as applied to tannery effluent
treatment in the United States. Primary clarification is accomplished by
means of coagulation and flotation, using electrolytic as well as mechanical
micro-bubble generation. The secondary biological section is a so-called
CARROUSEL, a technical modification of the Passveer oxidation ditch. Dur-
ing the 12-month study, complete analytical data representing winter as well
as summer operating conditions were acquired along with operating cost data.
This report presents these data and describes the design and operation
of the system. Possible applications of the same principles to other tannery
wastewaters are also suggested.
This report was submitted in fulfillment of Grant No. B 80^50^ by the
A. C. Lawrence Leather Co., Inc., under the sponsorship of the U.S. Environ-
mental Protection Agency. This report covers the period September 15, 19?6
through March 31» 1978 , and work was completed as of March 1, 19?8.
iv
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CONTENTS
Foreword iii
Abstract iv
Figures vi
Tables viii
Conversion Table ix
Acknowledgments x
1. Introduction 1
2. Wet Process Description 3
3. Treatment Plant Components 6
4. Primary Treatment 23
5. Secondary Biological Treatment 27
6. Experimental Procedures 31
7. Operating and Analytical Data, Discussion 38
8. Conclusions and Evaluations 84
9- Application of the System to Chrome-Cattlehide and
Vegetable Cattlehide Tanneries 94
10. Reuse of Treated Wastewater 134
References 145
Bibliography 147
Appendices
A. Letters from J. L. Witherow to J. A. Reid concerning
analysis of standard samples for analytical quality control 149
B. Initial cost of Winchester Tannery Wastewater Treatment
Plant 151
v
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FIGURES
Number
1, Schematic Diagram of Winchester Treatment Plant. 7
2. Holding and Equalizing Tank 9
3. Constant Head Box 9
4. Schematic Diagram of Constant Head Box 10
5. Dispersed Air Generator 12
6. Coagulation Cell 12
7. Bubble Classifier 13
8. LectroClear Flotation Basin 13
9. Schematic Diagram of LectroClear System 15
10. Filter Press 18
11. Schematic Diagram of Oxidation Ditch 19
12. Carrousel Oxidation Ditch 20
13. Final Clarifier 20
14. BOD^ Levels in Raw Wastewater, After Primary Treatment, 54
5 and After Total Treatment, First Sixty Weeks
15. Temperature and pH in the Carrousel, First Sixty Weeks 55
16. Food to Microorganisms Ratio and Relationship to Final BCD-. 56
First Sixty Weeks 5
17. Average Age of Suspended Solids in the Carrousel. First 57
Sixty Weeks
18. Suspended Solids in the Carrousel and Sludge Volume Index. 58
First Sixty Weeks
19. Suspended Solids in Raw Wastewater; after Primary Treat- 59
ment; and after Total Treatment. First Sixty Weeks
20. Nitrogen in Raw Wastewater; after Primary Treatment; and 60
after Total Treatment. First Sixty Weeks.
21. Ammonia Nitrogen in Raw Wastewater; and afte'r Total 61
Treatment. First Sixty Weeks.
22. Fats, Oils, and Grease in Raw Wastewater; after Primary 62
Treatment; and after Total Treatment. Fizst Sixty Weeks.
23. Chromium in Raw Wastewater; after Primary Treatment; and 64
after Total Treatment. First Sixty Weeks.
24. BODjj Levels in Raw Wastewater; after Primary Treatment; 65
and after Total Treatment. Summer Test Period.
25. BODc Levels in Raw Wastewater; after Primary Treatment; 66
and after Total Treatment. Winter Test Period.
26. Suspended Solids Levels in Raw Wastewater; after Primary 67
Treatment; and after Total Treatment. Summer Test
Period.
vx
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2?. Suspended Solids Levels in Raw Wastewater; after Primary 68
Treatment} and after Total Treatment. Winter Test
Period. 6g
28. Sludge Volume Index for Carrousel Activated Sludge. y
Summer Test Period.
29. Sludge Volume Index for Carrousel Activated Sludge. 70
Winter Test Period.
30. Volatile Suspended Solids Levels after Primary Treatment 71
and in the Carrousel. Summer Test Period.
31. Volatile Suspended Solids Levels after Primary Treatment 72
and in the Carrousel. Winter Test Period.
32. Total Nitrogen Levels in Raw Wastewater; after Primary 73
Treatment; and after Total Treatment. Summer
Test Period.
33• Total Nitrogen Levels in Raw Wastewater; after Primary 74
Treatment; and after Total Treatment. Winter
Test Period.
34. Kjeldahl Nitrogen Levels in Raw Wastewater; after Primary 75
Treatment; and after Total Treatment. Summer Test
Period.
35• Kjeldahl Nitrogen Levels in Raw Wastewater; after Primary 76
Treatment; and after Total Treatment. Winter Test
Period.
36. Ammonia Levels in Raw Wastewater; and after Total Treat- 78
ment. Summer .Test Period.
37• Ammonia Levels in Raw Wastewater; and after Total Treat- 79
ment. Winter 'Test Period.
38. Fats, Oils, and Grease Levels in Raw Wastewater; after 80
Primary Treatment; and after Total Treatment.
Summer Test Period.
39• Fats, Oils, and Grease Levels in Raw Wastewater; after 81
Primary Treatment; and after Total Treatment.
Winter Test Period.
40. Chromium Levels in Raw Wastewater; after Primary Treat- 82
ment; and after Total Treatment. Summer Test Period.
41. Chromium Levels in Raw Wastewater; after Primary Treat- 63
; ment; and after Total Treatment. Winter Test Period.
42. Schematic Diagram of Proposed Wastewater Treatment Plant 98
for a. Category 1 Chrome Tan Pulp Hair Cattiehide
Tannery.
43. Schematic Diagram of Proposed Wastewater Treatment Plant 120
for a Category 3 Vegetable Tan Save Hair Cattlehide
Tannery.
44. Schematic Diagram of a System for Proposed Re-use of 141
Treated Wastewater.
vii
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TABLES
Number Page
1. Typical Winchester Effluent Analysis 5
2. Laboratory Data Required for E.P.A. Project 32
3. Analytical Laboratory Quality Control Comparison of 35
Results on Divided Samples
4. Analytical Laboratory Quality Control Comparison of 36
Results Between A.C. Lawrence and E.P.A. I.E.R.L.
5. Analytical Laboratory Quality Control Comparison of Re- 3?
suits On Samples Run in Duplicate
6. Summer Operating Conditions 39
7. Winter Operating Conditions 41
8. Summer Analytical Results ^J 3
9. Winter Analytical Results 46
10. First Sixty Weeks Analytical Results 49
11. Average Percent of Pollutant Removal. Total Treatment. 84
Summer and Winter Test Periods.
12. Comparison of Winchester Effluent with Best Available 88
Treatment Standards for 1983
13t Comparison of Costs of Operation of Systems to Provide 92
Microbubbles for a Flotation System for Sus-
pended Solids Separation
14. Comparison of Carrousel Treatment Efficiencies 93
Winchester, N.H. vs. Oisterwijk, Netherlands
15. Typical Tannery Wastewater Analyses 95
16. Summary of Treatment Plant Components and Estimated Cost 117
for a Category 1, Chrome Tan, Pulp Hair, Cattle-
hide Tannery
17. Summary of Treatment Plant Components and Estimated Cost 132
for a Category 3, Vegetable Tan, Save Hair,
Cattlehide Tannery
18. Recap of Savings Possible Through Wastewater Recovery and 14,0
Reuse.
19. Recap of Estimated Effluent Reuse Construction Costs 144
viii
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Multiply (English Units)
English Unit
British Thermal Unit
British Thermal Unit/pound
cubic foot/minute
cubic foot/second
cubic foot
cubic foot
cubic inch
degree Fahrenheit
foot
gallon
gallon/minute
hdrsepower
inch
pound
million gallons/day
pound/square inch (gauge)
square foot
square inch
tons (short)
yard
CONVERSION TABLE
by
Conversion
0.252
0.555
0.028
1.7
0.028
28.32
16.39
0.555(°F-32)*
0.3048
3-785
0.0631
0.7457
2.54
0.454
3,785
(0.06805 psig+1)*
0.0929
6.452
0.907
0.9144
To Obtain Metric Units
Ketric Unit
kilogram-calories
kilogram calories/ldbgtam
cubic meter/minute
cubic rneter/rainute
cubic meter
liters
cubic centimeters
degree Centigrade
meter
liters
liter/second
kilowatt
centimeters
kilogram
cubic meters/day
atmospheres (absolute)
square meter
square centimeters
metric tons (lOOOMlq§raii)
meter
*Actual conversion, not a multiplier
IX
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ACKNOWLEDGMENTS
The authors wish to particularly acknowledge the indispensable devo-
tion and dedication to the task of gathering the extensive amount of data
over considerable periods of time, as provided by Mr. John A. Reid, Mr. M. R.
Reynolds, and Mr. Frank Russell, all of A. C. Lawrence Leather Company, Inc.
In addition to performing the on-plant chemical analyses, Mr. Reid arranged
for and directed the analytical work done commercially, and offered valuable
advice in the area of operational adjustments towatd maximizing treatment
efficiency.
The project is also indebted to Mr. Francis E. Stone, Plant Manager
at Winchester, who maintained a keen interest and directed prompt attention
to necessary maintenance details thus providing continuity of operation,
It is also appropriate to acknowledge the direction and assistance of
Mr. Jack L. V/itherow and Mr. Donald F. Anderson of the U.S.E.P.A. whose cap-
able guidance was essential to this project.
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SECTION 1
INTRODUCTION
Tanneries are generally pollution-intensive industrial complexes gen-
erating large volumes of high-concentration wastewaters. These wastes have
historically been discharged into rivers and waterways with little if any
purification. This report presents construction and operating data, includ-
ing analytical results, for a system designed to eliminate most of the ob-
jectionable components of a tannery effluent formerly discharged directly into
a small river.
Tanneries are not all alike. The basic design of procedures for hide
preparation, tanning, and finishing vary rather widely according to the types
of raw hides employed and the characteristics desired in the finished leather
product. Accordingly, the U.S. Environmental Protection Agency (EPA) has
classified the various segments of the industry into the following seven
categories:
1. Cattlehide - pulp hair - chrome tan
2. Cattlehide - save hair - chrome tan
3. Cattlehide - non chrome tan
4. Thru-the blue
5« Retan only
6. No beamhouse tannery
7. Shearlings
The tannery investigated here is a shearling tannery, which tans and
finishes sheep pelts with the wool intact. These skins, except for the al-
terations of character and appearance needed to accomplish permanent preser-
vation and enhance aesthetic qualities, are essentially the same entity re-
moved from the parent animal. The pelts are received at the Winchester tan-
nery either green salted or dry salted in railroad cars or auto trucks from
large-scale meat producing points in the Midwest, Fax West, or Atlantic sea-
board. The pelts contain large amounts of animal grease and interfibrillary,
water-soluble, proteinaceous compounds in the form of glycomucins and the
like, as well as large quantities of lanolin, wool grease, and soil attached
to or entrapped in the wool. These components are removed early in the pro-
cessing procedure during washing operations, which coax the grease and lano-
lin into dispersal through the use of strong detergents and emulsifiers.
The basic difference between a shearling tannery and a conventional
Cattlehide tannery is that the former requires no dehairing steps. This
process, known as beamhouse operations, involves the use of chemical agents
such as lime and sodium sulfide to produce either cattle hair suitable for
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resale or denatured (pulped) hair, most of which enters the waste stream in
the form of fine particles. Section 2 describes the shearling process, and
Section 9 presents designs for complete cattlehide processing systems.
The wastewater treatment system selected for the Winchester tannery
was chosen from a number of options. The electrochemical primary system,
sometimes called LectroGlear, was favored for several reasons:
1. The presence of large quantities spent fatliquor solutions and emulsi-
fied lanolin, wool grease, and animal fat all well dispersed, dictated
a clarification system that would involve flotation rather than gra-
vity separation.
2. Laboratory-scale demonstrations clearly indicated that the floated
skimmings would have a much higher solids content (perhaps on the
order of 10X) than a gravity system could deliver. Sludge storage,
handling, and dewatering would thus be expedited.
3. The continued flotation effect provided by the electrodes in the
flotation basin seemed to maximize primary clarification.
4. The electrolytic generation of chlorine coincident with the other
products of electrolysis appeared to have the beneficial side effect
of providing some disinfection.
5. At the time of selection, ammonia reduction was thought to be occur-
ring within the LectroGlear system. This effect was a possible plus,
but it was later f^und to be untrue.
The secondary system was likewise selected from a number of possible
choices. The carrousel concept, which is a technical modification of the
Passveer oxidation ditch, was brought to our attention by EPA and leather in-
dustry representatives who visited Holland in 19?4. They reported rather en-
thusiastically the simplicity of design, low cost, minimum land requirement,
adaptability to northern winter climate operation, ease of control of dis-
solved oxygen, and low operating cost. In addition, the most important, this
system was claimed to have the capability of both nitrifying and denitrify-
ing. Because all of these factors seemed to indicate superiority over other
known systems, consultant help was secured, and the decision made to install
a carrousel unit.
The choice of a sludge dewatering device was affected by the fact that
the land area of the tannery property was limited, and solid waste from the
treatment, plant thus had to be deposited at the regional solid waste manage-
ment facility. Samples were submitted. The material was accepted with the
stipulation that the dry solids content would consistently have to reach 35$£
to kVfo (and preferably 40%). Only one device, a filter press, could relia-
bly be expected to provide this performance.
The choices made in assembling this treatment plant have proved to be
wise. Consistently high-degree removals of pollutants have been achieved, in
most cases well in excess of discharge permit requirements.
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SECTION 2
WET PROCESS DESCRIPTION
Shearling processing is a complex procedure using a. much greater water-
to-hide ratio than most tanneries. Because the wool is retained and it is
desirable to keep the wool fibers attached to the pelts free from interweav-
ing and tangling, the practice of swimming the skins in chemical solutions
has been adopted. Other categories of tanning operations limit the chemical
floats to the smallest possible amounts. The liquor-to-skin ratio, by weight,
for each fill and drain is on the order of 2.5 to 1. With side leather, the
ratio is apt to be 1 to 1, and in some individual instances, it may be as
little as 0.25 to 1. The Winchester tannery uses approximately 90 gal of
water per pelt (7,500 gal per 1,000 Ib of green salted weight as received),
or on a weight basis, a ratio of 60 to 1. This seems very high, but is ne-
cessitated primarily by the extremely soiled condition of the pelts as re-
ceived- The tannery processes some 3iOOO skins per day and
discharges just under 300,000 gal of wastewater per day.
The process used at Winchester has evolved over many years of trial
and error and has gradually been optimized by experience. There is no close-
knit shearling trade group in the U.S. exchanging ideas for mutual benefit,
nor is there any standard procedure for converting raw pelts into finished
products. Many tannages are used in lias, tannery, ranging from glutaraldehyde
to modified mineral and vegetable tannages, depending on the end use and
characteristics desired in the finished shearling. The shearling process
consists of soaking and washing, pickling, tanning, retanning, dyeing, and
fatliquoring, drying, and dry finishing * This section describes the wet
processing steps, or those contributing to liquid waste volumes.
SOAKING AND WASHING
Chemicals used in the soaking and washing process are soda ash, de-
tergents (biodegradable), and bactericide. Skins are immersed in water in
batches of about 100 in a horizontal, semicylindrical wooden tub, on which a
paddle wheel is mounted. The above chemicals are added, and the paddle wheel
is rotated to provide a swirling action that enhances liquid contact with
both the skin and the wool. A number of fills and draws are executed during
the wash and rinse cycles. This is a overnight operation.
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PICKLING
Chemicals used in the pickling process include sodium chloride and
sulfuric acid. Skins are immersed again in paddle vats and gently agitated,
this time in 5% salt brine containing sulfuric acid sufficient to adjust and
maintain the pH to about 1.8. This operation is also an overnight one.
Equilibrium at the pH specified is achieved.
TANNING
Chemicals used in the tanning process are sodium chloride, basic
chromium sulfate, and sodium formate.
Skins are again immersed and gently agitated in paddle vats to which
the chromium tanning solution has bean added. This requires a 2-day expo-
sure. In some cases, depending on the product desired, the chromium solu-
tions are retained and reused. In others, certain dyes are added that pre-
vent reuse.
RETANNING, DYEING, AND FATLIQUORING
Chemicals used in this process are sodium chloride, basic chromium
sulfate, sodium formate, emulsified animal, vegetable, fish, and mineral
oils, and various dyestuffs. Similar equipment to that described in the
foregoing steps is employed. The only significant difference in the dyeing
and fatliquoring sequence is that much higher temperatures can be tolerated
by the now chrome-tanned skins, and such elevations can be used to advantage
in the exhaustion of the dye baths and fixation of the dyestuffs. The time
periods required are relatively short - on the order of 2 to 3 hr.
All of the above operations are carried on at the ground-floor level
of the tannery, and the liquid contents of the paddle vats discharge by
gravity to in-floor drains and sewers. This means that it is possible for a
number of vats to be discharging dissimilar solutions to the wastewater col-
lection system at the same time. Generally the soak waters are the first to
be sewered in the workday, beginning at about 3 a.m. and lasting until 3 p.m.
The pickle liquors are dropped from about 11 p.m. to 11 a.m. The tan liquors
from 7 a.m. to 2 p.m., and the color-fatliquor solutions from 7 a.m. to
3 p.m. The equalizing tank at the front end of the wastewater treatment
works blends dissimilar solutions and absorbs surges in hydraulic flows.
The blended waste stream is thus a complex mixture of organic and in-
organic chemicals, mineral and vegetable tanning materials, animal, mineral,
and vegetable oils, both raw and solubilized, and a spectrum of dyes. It is
a murky brew at best, sometimes red, sometimes blue, usually dirty gray, but
always a challenge to any sanitary engineer. A typical analysis of a compo-
site sample from the equalizing holding tank is as follows:
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TABLE 1. TYPICAL WINCHESTER TANNERY EFFLUENT ANALYSIS
Parameter rag/1
Suspended solids -------------- 1,150
BOD5 812
N%-N 32
TKN 75
FOG
Gr 99
Though this analysis may not appear to represent contamination loads
encountered at chrome side tanneries, it is not as different as one might ex-
pect (See Section 9)-
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SECTION 3
TREATMENT PLANT COMPONENTS
Treatment plant components are described briefly as follows. Sche-
matic views of the primary and secondary treatment systems, the constant head
box, the primary clarifier, and the carrousel are presented as Figures 1,4,
9, and 11.
PRIMARY CLARIFICATION SECTION
Screen House
The screen house contains a screen pit with a horizontal cylindrical
rotating monel screen. The screen measures 3 ft. diameter by 5 ft. long and
has 5/32 in. perforations on 1/2 in. centers. It is equipped with link chain
mounted bar rakes that continuously remove accumulated coarse suspended solids.
Manufacturer: Exeter Machine Co., Inc.
Lomura, Wisconsin
Raw Wastewater Pumps - 3
These are submerged pumps located in a sump adjacent to and having a
water level the same as the screen pit referred to above. These pumps ele-
vate the wastewater to the equalizing tank as required, and are actuated by
float switches in the collection sump.
Manufacturers Flyte Corp.
Model No. - 6 - CP - 3126
Capacity - 600 gpm. Mhp -9.4
Holding and Equalizing Tank
See Figure 2.
This is used to accumulate wastewater during working hours, absorb
flow surges, and serve as a supply tank to allow constant flow through the
treatment system.
Constructions Concrete, circular.
Size - 40 ft. diam. x 18 ft. deep
Capacity - 17QOOO gals.
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BUILDING OUTLINE
K
IU
RIVER
SAMPLE COLLECTION POINT
Figure 1. Schematic diagram of Winchester treatment plant.
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Supply Pumps - 2
These are submerged pumps located near the bottom of the holding tank.
They are activated by float switches iuoun'r.ed near the bottom of the tank.
They elevate the wastewater to the constant-flow head box - see next item.
Manufacturer - Same as raw wastewater pumps above.
Model and Capacity - Same as raw wastewater pumps above.
Constant-Flow Head Box
See Figures 3 and ':-.
This consists of a fiberglass vessel, cylindrical, open top, which has
an adjustable side weir with which to regulate the depth of water within it.
It has two bottom connections, one to supply - pumps located directly below
in the holding tank , the other to the treatment plant. It is lo-
cated within the holding tank, near the top, attached to the perimeter.
Wastewater is pumped upward into the head box in an amount greater than can
be absorbed by gravity flow through the system. The excess overflows the ad-
justable weir and cascades back into the holding tank, creating turbulence
beneficial to solids suspension and hydraulic mixing. The constant head pro-
vides a constant rate of flow to and through the system until the water level
in the holding tank is reduced to the point that the level sensing switch
shuts the primary system down.
Diameter (ft) k
Depth (ft) 6.?5
Volume (ft^) 84
Design flow (gpm) 400
Design flow (gpm/ft2)- 63.5
Design flow (gpm/ft3)_ 9.5
Dosing Pump - Alum
This is a small centrifugal pump used to meter in alum solution
(45% wt. solids) from a fiberglass storage tank holding a 24 hr. supply.
Manufacturer -Liquiflo Equipment Go.
Series 34 3gpm 1/2 in. 316SS.
Motor - G.E. 0.?5 hp DC
Variable speed 1725 rpm max.
Dosing Pump - Lime
This is an air actuated diaphragm pump used to add lime slurry (1Q&
solids) to the wastewater stream from a continuously agitated storage tank
holding a 24 hour supply.
Manufacturer - Dorr Oliver Corp.
Diaphragm slurry pump
Model ODS if in. - Comp. Air 45 psi.
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Figure 2. Holding anfl Equalizing Tank
Figure 3. Constant Head Box
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PLAN VIEW
ELEVATION
OVERFLOW RETURN
TO
HOLDING TANK
ADJUSTABLE
WEIR
FROM
HOLDING
TANK
OUTSIDE WALL
OF
HOLDING TANK
FIXED
WEIR
•*» TO TREATMENT SYSTEM
Figure H-* Schematic diagram of Constant Head Box.
10
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Dispersed Air Generator
See Figure >
This is an in-line mixer used to provide high frequency agitation for
dispersing compressed air introduced to it into fine microbubbles for floe
flotation.
Manufacturer - Greey Mixers, Ltd.
Toronto, Canada
Model No. - 4-LBC-200 Lightning
Impeller - 5 in. diam. 316 S3.
Motor - 2 HP 1150 rpm.
Coagulation Cell
See Figure 6
This is a sheet iron vessel consisting of a cylindrical top section
and a rectangular bottom section. It allows intimate contact to develop be-
tween microbubbles and minute solids in suspension. The wastewater flow
enters the chambers tangentially at the lower level and leaves tangentially
at the upper level, thus providing a vortex action. Effective residence
time +2 minutes.
Manufacturers Local sheet metal fabricator
Plans furnished by Swift Environmental Systems, Oak Brook, Illinois
Diameter top section (ft) ?•£
Depth top section (ft) 2.5
Length bottom section (ft) -------7-6
Width bottom section (ft) 7.6 ,
Depth bottom section (ft) ------- !.8
Dosing Pump - Polyelectrolyte
This is a small centrifugal pump used to continuously add polyelectro-
lyte solution in small quantity to the waste stream from a stock tank holding
24 hr. supply.
Manufacturer - Liquidflo Equipment Go.
Series 36 5 gpm 3/4 in 316 S3
Motor: G.S. 0.7.5 HP D.G.
Variable speed 1725 rpm max.
Bubble Classifier
See Figure 7
This is a rectangular open top steel tank located in the line of flow
between the coagulation cell and the LectroGlear basin. The wastewater leav-
ing the coagulation cell contains some bubbles which are too large to be
effective in floe flotation and cause agitation and disruption of the sludge
11
-------
Figure
Dispersed Air Generates?
Figure 6. Cosgulation Cell
12
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Figure 7. Bubble Classifier
Figure 8. LectroClear Flotation Basin
13
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blanket at the surface of the primary clarifier. This vessel allows oversize
bubbles to escape to the atmosphere prior to entering the primary clarifier.
Manufacturer - Local sheet metal fabricator
Length (ft) 4
Width (ft) 3
Depth (ft) 4.5
LectroClear Glarifier 1'2-3'4'5'6
See Figures 8 and 9-
This is a large rectangular steel tank in which coagulated suspended
solids rise to the surface, and are continuously skimmed off. Skimmer flights
are mounted on the top of the tank structure, 10* apart, traveling at 2.5'
per min. Travel is continuous while the system is operating. Floating
solids are pushed forward and up a beach into a continuously rotating screw
conveyor. The conveyor discharges the skimmed material into a receiving tajik
from which it is intermittently transferred to storage tanks to await compac-
tion. In order to avoid flow channelling in the basin, 4 baffles, equally
spaced, with 67% free space consisting of 3 in. holes on 4 in. centers, are
equally spaced about 7 ft. apart in the clarifier. These are made of marine
plywood. The clarifier contains 78» 2 3/16 in. diam. Duriron electrodes,
Type TA-2. They are operated in pairs with a surface to surface spacing of
half an inch. They are mounted in polypropylene cradles 10 in. above the
basin bottom. One half of the electrodes are concentrated in the front quar-
tile of the clarifier.
Manufacturer - Local sheet metal fabricator
Length (ft) -35
Width (ft) 12
Depth (ft) 5.5
Operating depth (ft) 5
Current requirement - amperes 1400 to 1?00
Current requirement - volts -_-___ 6 to 7 DC
Current Rectifier
This unit is used to furnish direct current to the electrodes in the
LectroClear clarifier for generation of electrolytic microbubbles to assist
in floe flotation.
Manufacturer - Oxymetal Industrial Corp., Warren, Michigan
Model - Udalite No. 4 MDV - 5000
Type - SASS C 460V
Water cooled.
Skimmings Pump
See Figure 9.
This is an open impeller centrifugal trash pump used to move skimmings
from the receiving tank at the LectroClear clarifier to the skimmings storage
14
-------
SKIMMER FLIGHTS
SCREW
CONVEYOR
BUBBLE CLASSIFIER
POLYELECTROLYTE
DISPERSED
AIR
PRIMARY
CLARIFIED
EFFLUENT
SKIMMINGS
COAGULATION PUMP
CELL
Figure 9. Schematic diagram of LectroClear system
-------
tank. It is actuated by a float switch in the receiving tank.
Manufacturer - Gorman Rupp Go 4
Capacity (gpm) __- 100
Model - 3 in Centrifugal
Motor - 3 HP 1750 rpm
Sludge Storage Tanks
These are large cylindrical steel tanks used to store and accumulate
primary clarifier sludge and return sludge frcm the secondary final clarifier
to allow compaction to be carried out at a convenient time.
Manufacturer - Local sheet metal fabricator
Height (ft) 15
Diameter (ft) 12
Volume (gal) 12000
Steel thickness (in) ----------- 3/8
Number ------------------ 2
SLUDGE COMPACTION SECTION
Sludge Compaction Pump
This is an air actuated diaphragm pump, which forces sludge from the
sludge storage tanks through steam heated tubular heat exchangers and through
the filter press.
Manufacturer - ¥arren Rupp Pump Go. Mansfield, Ohio
Model No. - SA3A Sand Piper
Air Actuation (psi) 75
Heat Exchangers
These are used to elevate the temperature of the stored primary and
secondary sludge to 175 F to aid in filter press compaction. Operated in
parallel.
Manufacturer - Eimco, Inc.
Length (ft) 14
Shell diameter (in) 8
Design - Two pass
Tube diameter (in) ------- 0.5
Number of tubes each pass - - - 12
Stainless steel 316
Number - 2
Air Compressor
This unit is used to supply compressed air to the sludge compaction
diaphragm pump and to the dispersed air generator.
16
-------
Manufacturer - Kellog American
Model No. B-462
Motor HP . 25
Pressure (psi) . 100 to 125
Filter Press
See Figure 10.
This unit dewaters and compacts sludges produced in the primary and
secondary sections to the degree required by state regulations for land-fill
material.
Manufacturer - Sperry Equipment Go.
East Aurora, Illinois
Model No. 48EHCL
Number of plates -------------- 75
Plate design
Width (in) . 48
Height (in) 48
Feed port Center
Feed vent -------------- Corner
Face pattern pyramid
Filter cloth fabric ------------ Polyester
nonwoven
BIOLOGICAL REDUCTION SECTION
Carrousel Oxidation Ditch 7-8.9.1°.11.12 13
See Figures 11, 12, 13,
This is one of the major components of the entire treatment system. It
is a closed loop raceway of patented design constructed of concrete, mostly
below grade. Two aerators, mounted at specific locations,provide dissolved
oxygen by aeration and hydraulic force for continuous circulation of contents
through the channels.
Manufacturer - Local construction contractor
Design and specifications - Envirobic Systems, Inc., New York, N. Y.
Design F/M ratio - (BOD/MLSS) 0.06
Design MISS ( mg/l) 5500
Length over-all (ft) 123
Width over-all (ft) 66
Operating depth under aerators (in) 98
Operating depth in channels (in) 79
Operating volume (gal) ----------------- 380,000
Channel length - total (ft) 610
17
-------
Figure 10. Filter-
18
-------
PLAN VIEW
TOR TWO
DO 1.0
AERATOR ONE
& DO 1.5
FINAL CLARIFIER SLUDGE
DO O.O
TO FINAL CLARIFIER
RETURN
ELEVATION
Figure 11. Schematic Diagram of Oxidation Ditch,
-------
gure 1?. Carrousel Oxidation Ditc
Figure 1.3. Final Clarifier
20
-------
Aerators -
Oxygenation capacity - Oo/hp/hr (ib) 3.5
Design formula - Q£ - 1.5 x BOD + 4.6 TKN
Number ----------- «__.._.__«.2
Manufacturer - Hubert Sneek
Type 190
Diameter (mm) 1900
Motorized adjustable immersion
Minimum (cm) ----------__-._. o
Maximum (cm) ---------------- 30
Motors - Drive motors
Manufacturer - Scorch
HP 20
Speed (rpm) ---------..----__ 1160
Immersion adjustment motors
Manufacturer - Leroy
HP 1
Speed (rpm) 1700
Final Clarifier
This j.s a rim flow clarifier with bottom sweeps directing settled solids
to a collection point. It removes biological solids generated in the oxida-
tion ditch and discharges a clear effluent to the river.
Manufacturer - Glow Corp.
Florence, Ky.
Model - UEOFLO
Diameter (ft) 46
Depth (ft) 9
Operating depth (ft) ----------------- 8
Feed ---------------------- - Peripheral
Sludge draw Center
Effluent outlet Center
Sludge Return Pumps
These pumps return solids separated from the wastewater flow in the
final clarifier to the oxidation ditch, or to the sludge holding tanks as
wasted.
Manufacturer - Midland Pump Co.
Model - Midwhirl No. 4WS-4511
Capacity (gpm) 350
Motor HP 30
HOUSING
All of the components of the primary section, and the solids compaction
equipment are housed in a prefabricated, insulated, steel building.
21
-------
Manufacturer - Butler Buildings, Inc.
Length (ft) 104
Width (ft) 40
Height - bottom of truss (ft) 16
Ventilation -
Exhaust fans at gable peak, each end.
Diameter (in) ----------------- 36
Speed (rpm) 500
22
-------
SECTION I*
PRIMARY TREATMENT
Evaluation of processes for primary wastewater treatment began at Win-
chester in 1971. During that year, following laboratory bench-scale work, a
pilot plant using electrolytic microbubbles and suspended solids flotation was
designed and constructed to treat 15 gpm. The preliminary runs with this
equipment were encouraging but not successful because of incomplete flotation
of solids.
Modifications were made, and during the summer of 19?2, preliminary test
runs were repeated. These pilot tests clearly showed that the eleetroflota-
tion basin alone was inadequate to give reproducible and consistently accept-
able treated wastewater. Finally in 1973, an electrocoagulation cell was de-
veloped, designed, and installed just ahead of and in series with the electro-
flotation basin (Figure 9 ). This step was the key to success.
During the summer of 197^i round-the-clock runs were made operating the
pilot unit at 12 gpm. These tests lasted for several weeks, and the results
conclusively showed that the two-step electrocoagulation electroflotatlon
technology could provide the results desired.
SISCTROCOAGULATION
123456
Theory of the Blectrocoagulation Process ' ''
The key step in this primary treatment is the addition of microbubbles
to the wastewater after metal coagulants have been added and before the addi-
tion of a polyelectrolyte. This step is especially important in wastewaters
that have suspended material of high specific gravity (3 and higher). In the
electrocoagulation cell, the surface charges on the pollutant particles are
neutralized by the metal coagulant. This condition brings about a growth in
aggregate size of pollutants. Under these circumstances, the high density of
the pollutants invariably leads to a rapid settling action.
The notable contribution of this new two-step technology is the addi-
tion of a buoyancy factor (microbubbles) to the pollutant particles. Pairing
of particles and microbubbles is enhanced either by vortex action or other
turbulence, which increases the probability of collision between pollutant
aggregates and microbubbles. Once the microbubble and pollutant particle
have collided and united, the addition of the polyelectrolyte flocculates the
solid-gas aggregate and forms a gross floe that is buoyant.
23
-------
In the initial work at the A. C. Lawrence Leather Company, only elec-
trolytic raicrobubbles were employed in the coagulation cell. Since that time,
extensive tests have shown that dispersed air as well as dissolved air can
effectively be used in the two-step process. Single-step jar tests carried '
out with direct-dissolved air flotation were not successful.
In summary, this two-step concept provides a useful new technology for
treatment of industrial wastewater.
Dispersed-Air Coagulation Cell Versus Electrocoagulation Cell
An electrocoagulation cell employing electrolytic microbubble genera-
tion was initially the only source of flotation and was evaluated at the
Winchester plant. The cell contained 126 TA-2 electrodes with a horizontal.
surface-to-surface spacing of half an inch. These electrodes were placed
beneath the wastewater flow pattern and were situated below the coagulation
cell proper. The electrolytic microbubbles generated at the electrodes rose
to the center of the vortex coagulation seclion by natural buoyancy.
¥astewater enters and leaves the coagulation cell tangentially. The
design called for the coagulation cell to use 6 to ? V DC and to provide a DC
current of approximately 3*000 A. Under these conditions, the volume of
electrolytic gases generated was 30 liters/min (STP, 2.0 vol % of the waste-
water treated). Microbubbles that coalesced in the coagulation cell were
vented through a 3-in pipe in the center of the vortex coagulation unit.
Problems developed quite early in the electrolytic microbubble genera-
tion section. The wooden electrode supports deteriorated rather quickly, and
some electrodes shorted out. Problems also occurred with wool and debris ac-
cumulation on and around the electrodes,which interfered with good bubble
formation. Our consultants suggested as a remedy the use of an in-line mixer
that, when properly supplied with air, could cause minute bubbles to form
directly in the waste stream.
This dispersed-air generator, which is produced by Lightning Mixer
(Figure 5)1 is housed in a 10-in. diameter pipe that is placed just before
the vortex coagulation cell. Compressed air (10# psi and higher) is fed to
the bottom of the mixer. Air volume is regulated,,in the mixer by a rotaraeter
valve, which is adjusted for a flow of about 2 ft^ (56.6 It/min STP). The
microbubbles generated by the dispersed-air device are definitely coarser
than those generated electrolytically. A small percentage of bubbles pro-
duced by the dispersed-air device are very large, approaching 2,000 microns
in diameter. These microbubbles are deleterious to the overall process and
must be removed in the fractioriator. This device is an open-top vessel lo-
cated approximately 10 ft downstream from the vortex coagulation cell (see
Figure 9). The microbubble fractionator is 3 by 3 ft and 4 ft high. Bubbles
larger than a certain size (approximately 400 microns in diameter) exit from
the wastewater through the fractionator. The fine bubbles, because of their
slow rise rate, are held in the hydraulic flow pattern. Failure to use a
bubble frationator invariably leads to poor results in the electroflotation
basin, since the wastewater carries large bubbles into the flotation basin,
where the turbulence they
24
-------
create breaks up the floe as it is being skimmed off.
ELECTROFLOTATION
A major component in the primary treatment system follows next in the
sequence, the LectroGlear flotation basin (Figure9 ). The design was fur-
nished by Swift Environmental Systems of Chicago, the holder of patents in
connection with the application of this device. The flotation basin contains
microbubble-producing electrodes that perform two main functions! the first
is to provide assistance to stray floe agglomerates that may not have ac-
quired enough bouyaney in the coagulation cell to help them to the surface,
and the second is that as the microbubbles rise and encounter the underside
of the floating sludge blanket they add bouyaney and raise
the top of the blanket above the water surface. As a consequence of this
action, substantial dewatering occurs through downward flow of water and the
solids content of the skimmed sludge increases to as high as 1($. In actual
practice, the operators say that all is well with the system when the skim-
mings look like wet crumbly gingerbread,
SOLIDS COMPACTION
The skimmings, which now contain nearly all of the influent suspended
acO.idSj are directed by the screw conveyor on the LectroGlear flotation basin
to a transfer purap and thence into storage tanks to await charging into the
filter press during the normal working day* They are withdrawn from the
storage tanks by means of an air-actuated diaphragm pump called a Sand Piper,)
which is particularly efficient for this purpose. At the end of the charging
cycle, the pump is working at 100 psi and thus creates a very solid cake in
the press. Filtration and compaction are enhanced by raising the temperature
at 150° F or so, hence the inclusion of a heat exchanger between the Sand
Piper and the filter press,
OPERATION OF THE PRIMARY SECTION
The plant obtains about 90$ of its water for processing from the
Ashuelot River. City water is used for drinking and for certain limited
plant processing steps. Dumping of the water used for processing the pelts
occurs between the hours of 3 a.m. and 7 p.m., with the peak, hydraulic waste-
water flow occurring at about 11:00 a.m. As the wastewater leaves the plant,
it passes through a stainless steel, cylindrical Stehling screen where some of
the wool fiber is removed. From this point, the water passes into a 3»000-gal
pit and is then pumped directly into the 170,000-gal holding tank. Wastewater
in the holding tank is lifted by an immersion pump and passes through a head
box that provides the hydraulic head to feed the primary LectroClear operation.
This hydraulic head provides a flow of about 300 gpm, and the wastewater flows
by gravity from the headbox to and through the entire primary phase.
When the wastewater leaves the head box (in a 10 in. pipe), 1,000 mg/1
of alum is added. At a distance of approximately 20 ft from the alum addition
25
-------
and just "before the dispersed-air device, 800 ppm of hydrated lime is added
from a 10 vi,% lime slurry. Both chemical additions are added by metering
iV.jj; manually set to a predetermined feed. The wastewater then passes through
the dispersed-air device and the vortex coagulation cell for a dwell time of
2.2 min, after which 12 mg/1 of polyelectrolyte is added (X-400 Swift anionic
polyacrylic acrylamide). At this point, the pH is consistently between ?.5
and 8.5. The pH is monitored frequently, and deviations from the just-above-
neutral zone are corrected by adjustment to the lime-feeding mechanism.
The intention was to control pH by automatic adjustment of lime feed-
ing. Equipment was provided for this at the outset, but thus far, manual ad-
justment has not only been found to be adequate, but more reliable.
The system is designed as an on-off operation. This on-off control is
carried out by a float switch in the holding tank. When the water in the
holding tank is above a predetermined level, the float switch keep all pumps
and power on. Conversely,when the water is below a certain level, it keeps
all pumps and power off.
26
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SECTION 5
SECONDARY BIOLOGICAL TREATMENT
OXIDATION DITCH7'8'9'10'11'12'13
The secondary wastewater treatment process consists of biological re-
duction using an oxidation ditch of proprietary design known as a CARROUSEL,TO
and a rim flow clarifier.
The carrousel concept was first applied to sewage treatment in 1968 at
Oosterwolde, Netherlands. Today more than 100 carrousel installations are in
operation. Capacities range up to 300 mgd flow with 500 to 600 mg/1 BOD.
Dairy, food, tannery, brewery, chemical, pharmaceutical, and paper industry
wastes have all been treated. The first carrousel installation in the United
States went on line in December 19?6 at the A. C. Lawrence Leather Company, at
Winchester, N. H.
The carrousel is a technical modification of the original oxidation
ditch developed during the 1950's by Dr. Ir. A. Pasveer of the Netherlands
Research Institute for Public Health Engineering, Delft, Holland. Several
thousand of these oxidation ditches are in operation worldwide. Aeration in
the original ditches was supplied by horizontally mounted cage rotors, whose
oxygenation rates and amounts depended on the rotor design, immersion depth,
and the rpm.
The extended aeration process used in most oxidation ditches yields a
high percentage of BOD, COD, and suspended solids reduction and a sludge that
has been aerobically digested. The latter is a result of the endogenous res-
piration phase undergone by microorganisms.
The carrousel concept was developed and patented by Dwars, Heederik en
Verhey, B.V., Amersfoort, Holland ~ a European consulting firm. It is a hy-
draulic application of vertically mounted mechanical aerators that impart oxy-
gen and- that simultaneously provide sufficient horizontal velocity to prevent
solids from settling in the aeration channels. Final settling tanks are the
only major components needed in addition to the aeration channels for most ap-
plications. Settled sludge is returned to the aeration unit, with excess
sludge being wasted periodically.
The number of aerators and the size are based primarily on the amount
of oxygen needed. In turn, the channel cross-section dimensions are based on
the aerator impeller size. The channel length is a function of the volume,
which is related to the treatment efficiency or the type of activated sludge
27
-------
process selected. Special shaping is used to optimize the velocity. The
platform or bridge must be designed to handle all of the forces and vibrations
associated with the aerator. See Figure 11.
The common design factors or criteria required to produce a BOD reduc-
tion of 95% to 99% and a GOD reduction of 90$ to 95% are as follows:
a. Mixed liquor suspended solids (inLSS) (mg/l) ----- 5000 to 6000
b. Organic loading (ib BOD/lb MLSS/day) --------- 0.05 to 0.10
c. Oxygen supply (lb/lb BOD) -------------- 2.0 to 2.5
d. Hydraulic volume (ft3/lb BOD) ------------ 80
The carrousel can be operated to achieve nitrogen removal without addi-
tional treatment units and without the use of chemicals for a carbon source.
Thorough nitrification is achieved by large numbers of nitrifying organisms
maintained in the aeration unit. The high MISS, the long retention time, and
the well-conditioned sludge are all conducive to good nitrification.
After the organic nitrogen has been oxidized to nitrate, denitrif ica-
tion is accomplished by specific strains of organisms in the carrousel. A
section of the channels is made to operate at or near zero D0(0 to 0.5 ^.g
thus creating a favorable environment for denitrifying bacteria. This may be
accomplished by automatic control of the dissolved oxygen concentration at the
aerators by using a DO probe and instrumentation that can activate a mechanism
to change the depth of immersion and thereby the rate of oxygenationj or by
manual depth adjustment. The mixed liquor is passed through this anoxic zone,
in which an adequate carbon source is available from the continual inflow of
raw waste , during which denitrif ication takes place . This phase lasts only a
few minutes, as the velocity in the channel normally exceeds 1 fps. Odor pro-
blems do not develop because of stable sludge condition as well as the very
short time period in the anoxic zone for each pass. An advantage of combining
oxygenation and denitrification in the design is the release of oxygen during
denitrif ication for BOD removal.
The interconnection of DO probes and instrumentation with the aerators
to allow the automatic monitoring of DO levels to control immersion depths of
the aerators on this carrousel has not been successful to date. Since this
was a design feature A. G. Lawrence has, on several occasions, attempted to
derive satisfaction on this point from the licensor, but as of the close of
this demonstration period the control of » immersion depths is manual.
FINAL GLARIFIfiR
A high content of suspended solids (7000 to 8000 mg/l) is generated in
the carrousel through bacterial activity. This material must be. removed be-
fore the wastewater flow can be released to the river. A rim flow clarifier
is used for this purpose having a maximum solid flux design load of 1.0 lb/ft2
per day, and peak flow limited to 600 gal/ft2 per day. Suspended solids re-
moved by this clarifier are continuously returned to the carrousel or wasted
to the sludge holding tanks for a period each day.
28
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OPERATION OF THE SECONDARY
Dissolved Oxygen Control.
The measure of dissolved oxygen at the aerators is used to control the
biological activity and operating efficiency of the carrousel. The operator
uses a portable DO meter for this purpose, taking readings at least daily, and
more often if necessary or desired, just downstream from aerators one and two.
Aerator one is designated as the unit nearest the discharge point, and since
this is next adjacent to the anoxic zone it is required to furnish oxygen to
the greater degree.
The operating goal is to maintain a level of 1.5 mg/1 of dissolved oxy-
gen at aerator one and about 1.0 mg/1 at aerator two, with residuals of 0.5
at the section of the carrousel farthest from the aerators, and at or near
zero at the discharge point. See Figure 11 .
Since dissolved oxygen is almost if not non-existent in the wastewater
stream as it emerges from the carrousel it is necessary to substantially raise
the DO before discharge to the river. Stream requirements call for a minimum
of 4 mg/1. This is accomplished with four waterfalls, each with a free fall
of about three feet. The first is at the carrousel discharge overflow weir,
the second is at the overflow weir at the final clarifier, and the third and
fourth are arranged between the final clarifier and the river. Through these
waterfalls the stream specification for dissolved oxygen as required by the
State of New Hampshire is satisfied.
Suspended Solids - Activated Sludge
Mixed liquor suspended solids (MISS) and mixed liquor volatile sus-
pended solids (MLVSS) are sampled and analyzed at least weekly at sample
point 83. These are indicative of the biological activity in the carrousel.
It is desired to maintain the MLSS at ?000 to 8000 mg/1 and the MLVSS at 60
to 65$ of MLSS.
Since the wastewater passing from the primary treatment section to the
secondary treatment section (carrousel) is relatively free from suspended
solids the high analytical values for MLSS and MLVSS are the result of bib- •
logical activity. These solids are removed in-the final clarifier. They are
continuously completely returned to the carrousel except for a period each day
when a portion is wasted into the sludge holding tanks to be concentrated in
the filter press and directed to land-fill. The time of wasting each day is
dictated by the actual level of MLSS at 83 compared with the desired operating
concentration. It is usually about four hours.
Phosphorus
Phosphorus is nutritionally required for vigorous bacterial life sup-
port. It is found in relatively large concentrations in the Winchester tan-
nery wastewater, amounting to as much as 20 mg/1. The chemicals used in pri-
mary treatment, principally alum and lime, remove or combine with some of the
phosphorus, however, making it mostly unavailable as t£ nutrient for the bac-
29
-------
teria in the secondary treatment section. The accepted nutrient ratio of
100 BOD to 5 nitrogen to 1 phosphorus for good bacterial growth indicates that,
for every 100 parts of BOD treated, one part of phosphorus must be available.
At this treatment plant the mean BOD loading to the biological section
is 280 mg/1 or an average of ?00 to 800 pounds per day. On this basis the
daily addition of 2 gallons of 75$ phosphoric acid, containing approximately
six pounds of phosphorus as P, in addition to the residual available in the
flow to the secondary, was dictated. The resulting BOD reductions and other
manifestations of biological activity demonstrated that the amount was suffi-
cient. The phosphorus content in the final effluent is low, usually 5 mg/1
or less, indicating good balance of biological usage and chemical absorption.
When the plant started operation in December, 19?6, foaming on the
oxidation ditch was extensive. Anti-foaming agents were considered, but as
the MISS increased the foaming decreased. As the MLSS approached design
foaming was no longer present.
30
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SECTION 6
EXPERIMENTAL PROCEDURES
SELECTION OF PARAMETERS
Soon after this demonstration project was approved and accepted by
E.P.A. a meeting was held at Winchester at which all of the principals of the
program were present, including the project officer, the project director,
the consultants, and local operating personnel. Data collection and analysis
were discussed in detail. The parameters considered essential are listed in
Table 2, along with where and how the samples for them should be taken. In
addition to those listed a number of daily measurements and readings were
specified which would be needed to properly assess the performance and allow
operating costs to be calculated. These were:
Pelts processed
Lime consumed
Alum consumed
Polymer consumed
Electricity consumed
Dissolved oxygen at aerators one and two
Depths of the top of the sludge blanket in the final clarifier
Primary sludge volume
Secondary sludge volume wasted
Outside temperature
Values for all of the parameters and readings for the special periods of this
project are given in Section 7, Tables 6, 7, 8, and 9. The absence of chemi-
cal oxygen demand (COD) as an analytical parameter and measure of performance
will be noted throughout this report. The high concentration of chloride in
the waste stream, unchanged during the treatment process, interfered with the
analytical procedure to such a degree as to render the determination useless.
SAMPLING PERIODS
Activated sludge operations are temperature-dependent, and most full-
scale wastewater treatment systems are expected to reduce BOD more efficiently
in summer than in winter. The claimed superiority of the carrousel design in
this respect prompted a large share of the interest in this project. A specJal
condition for data collection and analysis was set forth in a grant amendment
dated August 23, 1976. This condition was:
The sampling and data collection procedure in part IV-e
of the proposal shall:
31
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N>
Parameter
Dissolved oxygen
BOD5
Solids-total
-Suspended
-volatile
-Settleable
PH
Fats, oils, grease
Nitrogen-Ammonia
Kjeldahl
Nitrite
Nitrate
Phosphorus-Total
Chromium-Cr
Fecal Golif onn
Flow
Temperature °G
Chloride
Sample Type
TABLE
Equalized
influent
sl
D**
0
D
D
D
D
D
D
D
D
0*
G*
2. LABORATORY
Primary
effluent
S2
D
D
D
D
D
D
D
C
DATA REQUIRED
Carrousel
effluent
s3
D
D
D
D
D
G*
FOR EPA PROJECT
Final Return
effluent sludge
s^ s5
D
0**
D 0
D
D
D
D
D
D
D
D
D
D
0
G* G
Primary Dewatered
sludge sludge
s6 s?
C
0
0
0
0
G G
* 2 hour intervals during working day
** Frequency D - Daily 0- Occasionally
-------
—be performed on not less than 25 days of
typical operation during the winter and on
not less than 25 days of typical operation
during the summer.
At the time of selection of parameters and data readings it was
established that operating temperatures for mixed liquors would be limited to
a minimum of 21°G for summer operating conditions, and a maximun of 16°C for
winter. On eight occasions during the winter this rule was violated slightly,
particularly toward the end of the operating week, when the warm wastewater
from the tannery was sufficient to offset atmospheric cooling. The average
temperature recording in the carrousel at 83 during the winter period was
15.60C. This result demonstrates the innate resistance of the carrousel to
atmospheric interference, since the average of the outside highs and lows was
minus 8.8, and the lowest low minus 26°C.
SAMPLING
The following procedures were used for procuring samples at sample
points Si through Slj,. See Figure 1.
BI - wastewater from the holding and equalizing tank. This is also
called raw wastewater in this report.
Four 1 liter grab samples were taken from the tank at approxi-
mately 2-hr intervals. These were refrigerated, and composited
at the end of each day.
So - effluent from LectroClear primary treatment. An Isco sampling
instrument was used. Ice was employed in the instrument. The
device was programmed to sample 10 ml every 15 min.
So - grab samples taken at the discharge overflow weir of the carrou-
sel. These were taken four times a day at about equal intervals,
refrigerated, and composited at the end of each day.
Sn - grab samples taken after discharge from the final clarifier four
times a day at about equal intervals, refrigerated, and composited,
ANALYTICAL METHODS
The analytical methods used were those specified inj
Methods for Chemical Analysis of Water and Waste 1976
U.S. Environmental Protection Agency
FREQUENCY OF ANALYSES
Since two periods of intensive sampling were specified for this pro-
ject, 25 days of summer conditions and 25 days of winter conditions, sampling
and analysis were performed five days each week for five consecutive weeks
beginning September 12, 1977, and for 25 working days of seven consecutive
weeks beginning December 12, 1977, and extending into February, 1978.
33
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PERFORMANCE OF ANALYSES
Routine weekly analyses have been performed in the laboratory at the
Winchester wastewater treatment plant since start-up. This routine was not
interrupted during the demonstration periods.
Since daily analyses are not feasible in the on-plant facility most of
the analytical work for this project was performed by Tighe and Bond, a
certified and approved laboratory located at Easthampton, Mass. Composite
samples from sampling points Sj., 831 83, and S^ were delivered by A. G.
Lawrence personnel to Tighe and Bond each day on the day they were obtained.
It will be noted in reviewing the tables of analytical data, and the
graphs, that analysis was not made for every parameter at all four sampling
points. Those not showing were considered by the project officer and consul-
tants to have insufficient significance to be included.
QUALITY CONTROL
Two approaches to quality control of analytical work were used.
v
The first was the analysis of identical samples by the A. C. Lawrence
laboratory and by Tighe and Bond. Composites from each of the sampling
points Sj_, S£, 83, and Sty were divided on three separate days, one portion
going.to each laboratory. The results are presented in Table 3. Examination
of the comparative values reveals very few instances of unsatisfactory agree-
ment. A. C. Lawrence results were consistently higher for nitrite in the
final effluent, and one Tighe and Bond analysis for fats, oils and grease was
so high as to be technically suspect. Otherwise there were no deviations be-
tween laboratories in excess of standard.
The second approach was the furnishing of standard samples by the
U.S.E.P.A. Industrial Environmental Research Laboratory to the A. C. Lawrence
laboratory at Winchester. The samples were received in May, 19?8. Results
by A. C. Lawrence were reported early in July. The values reported and the
values provided by E.P.A. for the standard samples are presented in Table If.
The agreement was generally good. A critique of this effort prepared by the
Project Officer is presented as Appendix A.
The third quality control measure was the analyzing of samples in
duplicate in the. treatment plant laboratory. These analyses are presented
in Table 5« The agreement is good for all parameters.
PRESENTATION OF DATA
No statistical analysis of data has been attempted. All analytical
determinations as presented in the tables are as reported by the analysts.
In some cases inconsistencies occur, such as ammonia nitrogen in excess of
kjeldahl nitrogen in the same sample. These are considered to be within the
experimental error.
34
-------
TABLE 3. ANALYTICAL LABORATORY QUALITY CONTROL
COMPARISON OF RESULTS ON DIVIDED SAMPLES
OJ
Ul
Sample
Date
9/lV??
A. C. Lawrence *
Tighe and Bond **
10/12/7?
A . C . Lawrence
Tighe and Bond
12/12/7?
A. C. Lawrence
Tighe and Bond
9/14/7?
A . C . Lawrence
Tighe and Bond
10/12/77
A. C. Lawrence
Tighe and Bond
12/12/7?
A. C. Lawrence
Tighe and Bond
BODs (mg/l)
Suspended Volatile suspended
Solids (mg/l) Solids (mg/l)
Fats, oils
Grease (mg/l)
si £>2 *4 s»l i>2 *J &4 ^2 "3 al °2 34
960
990
8?0
790
988
980
Ammonia
(nw/i:
Si
25
32
39
40
41
31
131
262
366
34?
366
324
N
)
S4
0.50
0.4?
1.44
2.?0
2.?0
1.86
5
4
7 1,
6?0 141
828 150
104 410
6 1,005 412
6 1,
7
Si
104
73
76
81
91
82
0?0 135
992 194
TKN
(m«/l)
S2
4?
44
52
56
42
56
8
9
9
8
11
,360 30
,280 32
,730 64
,669 13
,362 19
12,360 68
S4
3.9
3-1
4.5
5.6
5-3
4.2
Nitrite
(mg/l)
S4
• 750
.180
.640
.295
.610
.164
105
126
868
905
76
102
5,010
5,550
6.750
5,205
7,120
7,610
Nitrate
OssZi)
S4
34.5
40.1
8.5
9-9
13.3
14.8
Si
82
70
95
110
120
115
539 32
401 33
454 82
480 101
548 37
559 22
Chromium
Cr (mK/1)
S2
7.9
5.5
28.
39.
11.9
9-5
8.8
5.4
0.8
18.0
5-5
3.2
S4
1.01
0.81
0.45
0.?4
0.60
0.61
* Treatment plant laboratory
** Commercial laboratory
-------
TABLE 4. ANALYTICAL LABORATORY QUALITY CONTROL
COMPARISON OF RESULTS BETWEEN
A. C. LAWRENCE AND E.P.A. I.E.R.L.
Sample
Parameter number
BOD5 1
2
COD 1
2
Ammonia-N 3
TKN 5
6
Nitrate-N 3
24'
PO^-P 3
4
Total - P 5
6
Chromium-Cr 7
8
9
A.C. Lawrence
value
20.9
94
74
234
3.08.
8.96
5.04
38.08
•925
6.46
.066
1.43
0.906
4.30
11.6
82,65
368.3
E.P.A. I.E.R.L.
value or comment
within one standard
viation
about 40^ low
within one standard
viation
within one standard
viation
2.6
8.8
2.1
38
1.2
6.7
.13
2.4
0.85
4.28
within one standard
viation
within one standard
viation
within one standard
viation
de-
de-
de-
de-
de-
de-
-------
TABLE 5. ANALYTICAL LABORATORY QUALITY CONTROL
COMPARISON OF RESULTS ON SAMPLES RUN IN DUPLICATE*
u>
BOD^
Date S/j,
10/5/77 A 3M
10/5/77 AA 3.25
10/5/77 A
10/5/77 AA
12/28/77 A
12/28/77 AA
Suspended
Solids (mg/1)
S^ Sg S-j S^
739 233 8,787 31.
725 223 8,990 31.
Nitrite Phosphate
N02(mg/l) PO^ (mg/1)
0.521 0.913
0.525 0.916
0.091
0.096
Volatile suspended Pats/oUs NH^-N
Solids (mg/1) graeeftiK/l) (mg/l)
s2 s3 s4 si s4
0 128 5,339 18 32 0.9
1 128 5,220 27 32 0.9
Chromium
Cr (mg/1)
sl S2
75-^ 2.^9
76.6 2.51
TKN
5.0^
^.48
S4
1.21
1.06
1.95
1.9^
* Treatment plant laboratory
-------
SECTION ?
OPERATING AND ANALYTICAL DATA
DISCUSSION
In connection with this special demonstration project two separate
test periods were selected, one in summer, one in winter, during which samples
were taken frequently, for most of the time daily, and analysed by an outside
laboratory. Analytical results for those periods are recorded in Table 8 and
Table 9.
During the entire period that this treatment plant has been in opera-
tion samples at each of the significant sampling points have been obtained at
least weekly, with few exception, and. analyzed by the staff analytical techni-
cian. Those results are presented in Table 10.
Thus three groups of analytical data have been accumulated from which
conclusions as to system capability can be derived.
Graphs of analytical results.
In order to more clearly show the levels and trends of parameter in-
cidence and removals across the treatment system a number of graphs have been
plotted. These follow as Figures 14 through 41. Parameters plotted are:
BOD5 (Ib/day)
pH
Temperature (°c)
Food to microorganism ratio in the carrousel
Sludge age (days)
Mixed liquor suspended solids (mg/l)
Mixed liquor volatile suspended solids (mg/l)
Sludge volume index
Suspended solids (ib/day)
Nitrogen as TKN, nitrate and total. (Ib/day)
Ammonia nitrogen (Ib/day)
Fats, oils and grease (Ib/day)
Chromium (Ib/day)
Where results are shown in pounds per day a rough conversion to milli-
grams per liter can be made by multiplying by 0.4. This assumes a normal
daily flow of 300,000 gals. The sampling locations and procedures are ex-
plained in Section 6.
38
-------
TABLE 6. SUMMER OPERATING CONDITIONS
Wastewater
Date Volume (gal)
9/12/7?
9/13/77
9/14/77
9/15/77
9/16/77
9/19/77
9/20/77
9/21/77
9/22/77
9/23/77
9/26/77
9/27/77
9/28/77
9/29/77
9/30/77
10/3/77
10/4/77
10/5/77
10/6/77
10/7/77
10/11/77
10/12/77
10/13/77
10/14/77
10/15/77
661,734
286,344
280,492
302,058
275,868
529,038
288,090
307,296
277,614
331,740
515,070
316,026
277,614
296,820
316,026
312,534
347,454
370,152
316,026
308,990
275,600
288,404
368,406
279,360
310,996
Est. Ave,
Pelts
Processed
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
3,120
Coagulants added
Lime**** Alum***
(gal) (gal)
1,986
1,102
1,010
1,290
1,019
4,045
1,369
1,100
1,750
2,400
2,098
1,912
1,202
1,974
2,554
1,808
2,772
2,608
2,090
1,794
1,210
1,390
1,409
1,392
1,561
1,485
800
540
560
600
1,209
804
804
610
810
590
610
544
675
651
630
910
870
689
576
620
786
970
806
775
Polymer**
(gal)
868
1,643
1,191
1,300
1,683
3,080
1,671
1,508
1,650
1,980
1,406
1,976
760
1,808
1,982
1,972
2,308
2,010
1,900
1,870
1,648
1,710
2,062
1,674
1,910
Si
6.2
6.0
5.1
4.9
4.9
6.8
6.4
6.1
6.7
5-7
5.6
5.0
5.4
6.0
4.0
6.1
5.2
6.7
5-0
4.6
5.0
4.8
5.5
3.9
5.6
PH
S?
6.1
8.0
7-5
6.4
9.4
9.1
7.5
7.7
8.2
8.6
7.8
7-9
10.4
8.7
7-9
7-4
5-9
8.0
7.3
7.4
5.6
7.8
8.9
6.2
7.5
SL.
6.7
7.2
7.4
6.8
6.9
7.1
7.3
6.6
6.9
7.1
6.9
6.5
7.5
7.6
7.1
7.0
6.6
7.3
7-5
7.2
7.4
7.5
6.7
6.5
7.1
T
Si
27
31
29
28
29
30
28
29
27
28
28
29
29
29
30
27
27
26
28
28
28
28
29
27
27
emp. (
Si
23
25
26
24
24
25
23
23
23
24
22
24
25
25
24
20
21
22
22
22
22
22
22
21
21
°fi)
O.S.*
11
12
14
15
15
17
16
8
9
10
9
14
10
13
9
12
7
8
11
7
7
9
9
7
6
**** 10# Solids
*** 45^ Solids
** 0.2$ Solids
* Average of outside high and low
(Continued)
-------
TABLE 6. (CONTINUED)
Flotatior
basin
Date
9/12/77
9/13/77
9/14/77
9/15/77
9/16/77
9/19/77
9/20/77
9/21/77
9/22/77
9/23/77
9/26/77
9/27/77
9/28/77
9/29/77
9/30/77
10/3/77
10/4/77
10/5/77
10/6/77
10/7/77
10/11/77
10/12/77
10/13/77
10/14/77
10/15/77
volts .
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7-2
7.2
7.2
7.2
7-2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
amps.
1,720
1,300
1,900
1,500
1,600
1,800
1,700
1,600
1,600
1,700
1,600
1,600
1,400
1,900
1,700
1,700
1,900
1,700
1,700
1,600
1,700
1,900
1,900
1,900
1,900
Primary
sludge
volume
(gal/day)
6,000
4,900
4,000
5,000
4,800
7,000
4.700
4,200
3,900
4,200
3,900
4,400
4,000
3,800
4,000
6,000
4,000
4,400
4,700
5,160
4,400
5,000
6,000
6,100
4,800
Dissolved
oxygen (ppmj
aerator
one
1.5
4.1
3.8
2.0
3.1
3.4
3.4
3.3
3.0
3.4
3.9
4.5
5.0
2.4
2.6
2.6
5.7
2.6
2.6
-
_
-
-
0.9
Settling T
Sq (m
two 83 a.m.
2.0 640
3.7 ' 900
3.0 ' 890
OUT ' 550
3.0 | 910
2.9 ' 870
3.0 ' 760
4.7 o 820
OUT o 900
3.0 8- 870
3.4 % 910
3.3 ^ 840
OUT KI 710
1.6 & 590
2.0 £ 790
-x3
3.4
4.9
2.3
2.4
-
_
-
-
0.5
670
910
970
840
890
850
850
940
870
850
sst £
1/1) c
p.m.(i
710
870
900
640
870
850
710
810
850
900
870
810
680
-
790
810
890
870
840
880
840
850
700
860
710
.econdary
Jlarifier
T;. clear)
4
3
3
5
5
4.5
5
5
5
5
5
5
5.5
1.5
4
5
5
5
5
3.5
5 .
4
3.5
4
4
Secondary
sludge waste
(gal/day)
2,400
1,920
1,200
2,400
2,400
2,000
2.700
2,100
2,300
2,450
2,300
2,150
1,975
4,800
2,500
3,430
2,940
5,880
3,675
2,500
3,400
2,900
2,205
3:, 000
-------
TABLE ?.
WINTER OPERATING CONDITIONS
Coagulants
Wastewater Pelts
Date Volume (gal) Processed
12/12/7?
12/13/7?
12/14/??
12/15/7?
12/16/7?
12/29/77
12/30/77
1/3/78
1/4/78
1/5/?8
1/6/78
1/9/78
1/10/78
1/11/78
1/12/78
1/13/78
1/19/78
1/23/78
1/24/78
2/1/78
2/2/?8
2/3/78
2/6/78
2/9/78
2/10/78
V y YiM 4 fyif
A A TtrK T^LJ/O
***45#
332,640
269,280
285,120
285,120
205,920
241,?40
180,540
306,000
264,180
233,640
250,272
290,700
300,960
313,296
-
180,720
306,858
301,410
323,136
313,650
91,392
178,500
317,016
312,732
184,212
Solids **
Solids *
3,205
3,210
3,429
3,190
3,510
3,650
3,773
3,600
3,58?
3,680
3,625
3,750
3,605
3,626
3,450
3,762
3,693
3,810
3,830
4.070
3,890
3,896
3,890
3,664
3,903
0.2fi Solids
Average of
added
Lime**** Alum*** Polymer*^
(gal) (gal) (gal)
2,045
1,269
1,018
2,04?
1,288
2,2?1
1,820
2,49?
2,705
2,538
2,576
1,916
2,138
2,522
2,388
1,83?
2,589
1,440
2,522
2,255
601
1,252
2,00?
2,095
1,570
outside
461
199
430
576
578
516
36?
642
65?
49?
489
626
720
751
65?
40?
?06
516
931
757
282
563
595
556
313
high and
1,380
776
979
857
801
1,423
1,171
1,835
1,683
1,651
1,585
1,811
1,340
1,804
1,171
1,085
2,27?
1,056
1,665
1,520
518
?02
1,534
1,68?
1,443
low.
It
si
5.5
5-7
6.4
5.2
4.6
5.6
4.2
4.4
4.7
4.9
4.8
5.4
4.9
5.0
5.0
4.5
5.2
4.8
5-3
4.9
5.6
4.9
5.1
5.4
4.5
vH
S2
7.5
6.8
8.3
8.2
7.7
9.2
7.8
9.0
8.8
9.0
8.8
8.1
7.4
8.6
8.5
8.0
7.3
6.2
8.2
6.7
7.5
8.0
7.8
7.4
7.9
Temp. (°G)
S4
7.1
7.5
7.5
7.0
7.*
7.1
7 .4
7.6
7.2
7.3
7-5
7.5
7-3
7.4
7.2
7.2
7.1
7.1
7.1
7.0
7.0
7.0
6.8
7.3
7-1
Si
23
24
26
25
26
24
24
26
26
26
28
21
26
26
2?
2?
26
24
25
25
26
24
24
26
26
83 QS.*
11 -5
14 1
16 -2
18 -5
18 -4
15 -12
15 -11
12 -10
15 -12
18 -11
19 -2
15 9
13 0
15 -14
18 -10
18 -5
15 -8
13 -9
16 -11
15 -13
17 -12
16 -12
13 -14
16 -14
18 -13
-------
TABLE ?, (CONTINUED)
Flotation
basin
Date
12/12/77
12/13/77
12/14/77
12/15/77
12/16/77
12/29/77
12/30/77
1/3/78
1/4/78
1/5/78
1/6/78
1/9/78
1/10/78
l/H/78
1/12/78
1/13/78
1/19/78
1/23/78
1/24/78
2/1/78
2/2/78
2/3/78
2/6/78
2/9/78
2/10/78
volts .
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
amps.
1,900
2,000
2,100
2,100
1,900
1,800
1,800
2,100
2,000
2,500
1,900
1,350
1,500
2,800
2,000
1,700
1,800
1,700
1,700
1,700
1,700
1,700
1,300
1,500
1,600
Primary
sludge
volume
(gal/day)
9,979
8,078
8,553
8,661
6,177
7,252
5,416
9,180
7,925
7,009
7,508
8,721
9,028
9,398
-
5,421
9,205
9,042
9,694
9,409
2,741
5,355
9,510
9,381
5,526
Dissolved
oxygen (ppm)
B
aerator
one
1.1
.8
1.1
.5
1.2
2.0
2.6
1.2
2.4
2.2
2.4
3.3
1.2
1.9
1.9
1.9
2.0
_
0.7
0.9
-
0.7
0.6
1.8
0.7
two
.30
.30
.50
.30
.30
.25
.25
1.10
0.25
0.25
0.25
1.75
1.1
1.0
0.15
0.15
0.20
_
0.10
0.30
-
0.35
0.30
0.15
0.15
S3
.20
'.20
.50
.10
.10
.25
.30
.20
0.25
0.25
0,50
1.90
0.20
0.20
0.15
0.25
0.20
_
0.30
0.20
-
0.35
0.30
0.10
0.30
ettling Test
S-, (ml/1)
a.m.
550
560
950
580
820
700
725
810
700
675
800
875
875
825
725
760
800
850
800
700
720
900
950
775
700
p.m.
625
670
825
600
710
535
750
750
660
630
590
800
775
650
800
650
700
825
740
750
770
800
810
690
625
Secondary Secondary
clarifier sludge wasted
(ft. clear) (gal/day)
5.0
5.0
4.0
4.0
4.0
5*0
5-0
7.0
6.5
6.0
6.0
7.5
3.5
2.0
1.5
4.0
2.5
_
1.5
2.0
2.0
4.0
5.5
5.0
3.5
1,800
1,800
1,800
1,650
900
1,920
1,920
1,920
3,840
1,920
2,560
^
3,520
2,560
2,400
2.720
1,920
2,280
2,304
1,920
-
-
1,500
-
-------
TABLE 8. SUMMER ANALYTICAL RESULTS
BOD.; (mg/l)
Date
9/12/77
9/13/77
9/14/77
9/15/77
9/16/77
9/19/77
9/20/77
9/21/77
9/22/77
9/23/77
9/26/77
9/27/77
9/28/77
9/29/77
9/30/77
10/3/77
10/4/77
10/5/77
10/6/77
10/7/77
10/11/77
10/12/77
10/13/77
10/14/77
10/15/77
10/18/77
10/19/77
sl
750
1,080
990
840
630
1,140
960
1,195
950
570
660
690
975
930
470
600
690
683
990
610
870
870
790
830
580
720
881
S2
288
270
262
252
210
300
284
283
322
246
308
354
315
336
240
192
246
248
312
216
300
366
347
288
312
252
286
S4
5
5
4
3
5
3
5
5
3
4
3
3
5
3
3
3
3
3
5
4
4
7
6
4
6
3
8
sl
884
702
828
1,098
480
1,414
1,028
1,020
896
558
988
1,294
1,225
1,222
674
972
954
732
1,078
676
1,022
1,104
1,005
1,004
608
1,164
1,080
Suspended
solids (mg/l)
S2
37k
192
150
160
230
182
256
40
210
122
214
160
81
316
306
308
180
228
236
118
332
410
412
252
316
142
96
s3
9,270
9,730
9,280
9,790
10,310
10,470
9,990
8,140
10,810
10,400
10,790
10,030
10,664
9,180
10,670
10,470
10,390
8,888
10,060
9,730
9,850
9,730
8,669
10,110
9,700
10,620
8,677
Volatile suspended
solids (mg/l)
S4
98
92
32
42
52
82
120
28
78
176
140
50
126
34
46
80
58
31
32
32
60
64
13
40
182
66
44
S2
216
98
126
50
72
96
110
28
86
68
94
92
41
158
178
176
124
128
142
54
174
254
262
132
182
84
59
S3
5,560
5,660
5,550
5,820
5,880
6,390
5,820
4,880
6,060
6,020
6,330
5,980
6.730
5,590
6,340
6,160
6,720
5,430
6,190
5,660
6,060
6,750
5,205
6,290
5,920
6,520
5,299
Pats , oils Chromium
grease (mg/l) Cr (mg/l)
Sl
283
462
401
470
282
439
298
550
258
223
510
573
596
402
266
1,563
439
370
452
265
377
454
480
415
218
413
542
S2
-}4
20
33
17
27
6
16
25
28
17
15
13
11
39
72
134
104
43
25
5
21
82
101
9
61
5
24
S4
0.6
0.8
5.4
1.6
4.4
1.2
0.8
1.5
5.6
4.4
4.8
3.6
4.6
3.2
2.0
6.6
2.8
2.2
2.8
0.8
1.2
0.8
18.0
2.8
1.8
4.8
7.0
sl
65
80
70
80
75
95
85
76
70
120
87
110
100
105
110
100
85
94
100
100
85
95
110
100
110
65
104
s2
17.1
4.5
5.5
6.5
^.5
2.2
5.0
2.5
7-5
8.0
7.1
11.3
3.8
9.2
22.0
17.5
6.5
11.5
23.2
3.5
12.0
28.0
39.0
6.3
27.1
1.6
4.7
S4
l.l
0.8
0.8
0.8
1.1
0.9
0.9
1.1
1,2
1.6
1.2
1.1
2.0
0.7
1.1
1.1
0.8
0.9
0.6
0.2
0.4
0.4
0.7
0.5
0.8
1.0
1.5
-------
TABLE s. (CONTINUED)
NHo-N
Date
9/12/77
9/13/77
9/14/77
9/15/77
9/16/77
9/19/77
9/20/77
9/21/77
9/22/77
9/23/77
9/26/77
9/27/77
9/28/77
9/29/77
9/30/77
10/3/77
10/4/77
10/5/77
10/6/77
10/7/77
10/11/77
10/12/77
10/13/77
10/14/77
10/15/77
10/18/77
10/19/77
sl
23
13
25
31
12
42
28
38
42
43
35
42
35
42
31
31
34
32
24
37
34
39
40
39
34
10
36
S4
0.9
0.5
0.5
0.6
0.2
1.2
0.5
1.0
0.3
0.4
0.4
0.5
0.6
3.1
3.2
0.7
0.4
0.9
0.4
0.6
0.5
1.4
2.7
3.5
3.8
0.9
2.4
sl
77
76
104
80
48
85
88
102
92
55
85
88
102
92
55
71
70
73
65
43
79
76
81
83
44
62
80
TKN
(mg/1)
S2
44
43
44
50
36
52
47
55
53
43
52
47
55
53
43
40
35
46
20
28
19
52
56
47
27
32
43
S4
4.2
1.4
3.1
4.8
4.2
3.4
3.9
6.2
3.3
5.8
3.4
3.9
6.2
3.3
5.8
3.6
3.1
4.8
2.0
5.0
2.8
4.5
5.6
7.8
8.7
3.9
6.7
NOo
mS4
.50
.18
.20
.22
.05
.01
.03
.52
.02
.10
.00
.51
.09
.02
.02
.02
.01
1.17
.01
.76
.11
.64
.30
.00
.30
.34
.00
NO^ Fecal *
(mg/1) Coliforms
9.7
35-5
40.0
41.0
45.5
62.0
51.0
55.0
35.0
2.5
61.0
63.0
75-0
66.0
46.0
61.0
53.0
48.0
22.0
2.5
13.0
9.0
10.0
8.0
5.0
23.0
9.0
4
60
56
204
36
<1
<1
<1
18
100
660
130
469
<1
160
<1
<1
7
24
18
36
30
70
66
18
12
40
*Colonies per 100 ml.
-------
TABLE 8 (CONTINUED)1
Ui
Date
10/12/7?
9/12/7?
9/14/7?
9/16/??
9/20/7?
9/22/7?
9/26/7?
9/28/7?
9/16/7?
9/26/7?
9/14/77
10/12/7?
10/7/7?
10/12/77
10/13/7?
10/19/7?
Total solids Chloride Press Cake
rag/1 BdmarySixLsB Secondary 3LuJp mg/1 #
S2 S^ 55 solids ?S solids S1 S^ Solids FOG Cr
17,880 10,212 7,291 5,775
8.?0
8.?6
6.43
8.08
7.69
8.29
8.25
1.66
1.21
21 2.0? 0.59
29 4.06 0.9?
Phosphate
POk
TKN mg/1
0.25
2.80
.25
4.48
1.30
0.65
0.00
1.00
0.45
0.54
0.50
0.12
0.00
0.66
*Parameters on this table required to be determined occasionally only.
-------
TABLE 9. WINTER ANALYTICAL RESULTS
ON
Suspended
BOD^ (mK/1) solids (mg/l)
Date
12/12/77
12/13/7?
12/14/77
12/15/77
12/16/7?
12/29/77
12/30/77
1/3/78
1/4/78
1/5/78
1/6/78
1/9/78
1/10/78
1/11/78
1/12/78
1/13/78
1/19/78
1/23/78
1/24/78
2/1/78
2/2/78
2/3/78
2/6/78
2/9/78
2/10/78
Sl
660
790
980
690
720
930
583
680
1,067
690
630
510
990
1,258
1,100
990
1,020
930
990
1,222
690
630
720
750
720
32
312
330
324
276
300
348
212
272
355
312
288
276
360
437
432
372
372
479
420
434
408
456
444
348
252
34
6
4
7
8
6
13
12
5
7
7
11
3
4
7
6
11
4
3
10
9
12
20
4
12
20
Sl
1,012
1,036
992
1,120
482
2,216
1,280
1,120
794
1,760
1,890
1,270
1,830
1,060
1,790
1,300
1,520
1,320
1,330
1,100
1,510
1,200
1,800
1,650
1,380
s2
282
146
194
174
148
212
292
342
151
330
348
186
320
159
336
280
200
732
310
248
298
406
438
476
236
s3
13,050
14,130
12,360
15,750
14,280
11,690
12,320
13,280
11,130
15,040
13,990
10,100
13,750
10,880
14,070
21,640
13,400
13,740
19,680
11,640
13,110
14,620
14,690
5,340
13,590
Volatile suspended
solids (mg/1)
S4
76
104
68
76
68
168
62
100
39
158
90
46
152
16
114
214
66
110
92
25
50
74
38
62
46
S2
190
82
102
98
110
108
158
156
82
100
140
118
186
101
170
158
108
262
166
175
216
256
306
292
114
s3
?,860
8,750
7,610
9,820
8,810
7,280
7,740
8,300
7,060
9,030
8,700
6,640
8,780
7,080
8,600
14,180
8,230
8,780
12,710
7,800
8,680
9,660
9,550
460
8,730
Fats, oils
grease (mg/l)
sl S2 S4
320
421
559
310
273
421
428
444
550
527
463
215
614
685
525
224
579
375
320
620
554
464
438
575
536
42
24
22
18
19
39
16
16
36
15
9
26
34
56
42
52
29
23
69
7?
60
90
92
73
34
0.8
7.5
3.2
2.8
3.8
0.4
1.2
2.0
10.0
0.8
1.8
2.6
2.2
1.8
2.0
1.0
4.0
3.2
5.1
2.3
2.6
6.8
3.0
3.4
3.2
Chromium
Cr (mK/1)
Sl
80
95
115
135
145
105
135
115
131
100
80
75
85
126
100
105
95
85
100
99
95
100
115
125
110
S2
18,0
8.0
9.5
6.5
8.1
7.0
11.0
6.0
6.7
17.0
1.7
8.0
10.0
7.6
7.0
6.0
7.0
15.0
8.0
11.0
10.0
18.0
16.0
5.0
22.0
S4
1.7
0.7
0.6
0.6
0.7
0.9
1.1
1.0
1.2
0.9
0.8
0.7
0.6
0.5
0.3
0.4
0.3
0.4
0.35
0.55
0.50
1.15
0.106
0.60
0.55
-------
TABLE 9. (CONTINUED)
Date
12/12/77
12/13/77
12/14/77
12/15/77
12/16/77
12/29/77
12/30/77
1/3/78
1/4/78
1/5/78
1/6/78
1/9/78
1/10/78
1/11/78
1/12/78
1/13/78
1/19/78
1/23/78
1/24/78
2/1/78
2/2/78
2/3/78
2/6/78
2/9/78
2/10/78
NH^-N
(mg/l)
Sl
15
29
31
18
44
2?
37
33
37
32
37
5
25
43
68
33
29
37
24
44
20
46
30
27
31
* Colonies per
S4
0.6
0.4
1.9
5.5
9.3
JJ-.5
12.4
0.0
7.0
13.4
15.5
0.0
5.8
3.7
6.1
16.7
5.5
1.2
15.5
16.0
7.5
10.0
1.4
16.2
28.0
100 ml.
Sl
(J-6
68
82
86
72
95
62
79
78
81 .
64
61
71
105
88
59
87
79
89
85
70
67
85
72
63
TKN
(mg/1)
S2
31
43
56
62
51
60
46
52
53
58
43
35
45
65
61
45
52
50
58
55
41
52
28
52
44
S4
0.6
0.4
1.9
5.5
9.3
4.5
12.4
0.0
7.0
13.4
15-5
0.0
5.8
3.7
6.1
16.7
6.7
1.4
15-7
14.0
21.0
23.0
1.7
16.8
30.0
(mg/l)
S4
.02
.01
.16
.01
.63
.00
.12
.00
.05
.03
.04
.03
.14
.04
.02
.03
.32
.03
.01
.019
.010
.006
.002
.030
.000
NCH Fecal
(mg/l) Coliforms*
SK. s4
0.44
0.44
1.48
0.44
0.62
0.44
0.89
3.30
0.51
0.00
3.50
3.70
1.30
0.33
0.00
1.10
18.20
5-30
9.60
0.13
0.00
0.62
1.60
0.44
0.44
28
4
40
110
7,000
<1
20
430
148
-------
TABUE 9. (CONTINUED)
03
Date
11/30/77
12/14/77
12/12/77
12/14/77
12/16/77
12/19/77
1/3/78
1/6/78
1/10/78
1/11/78
1/12/78
2/6/78
2/8/78
12/15/78
1/23/78
11/30/77
1/12/78
Total solids Chloride Press Cake
m^/1 PrimarySlute SesorriarySM^ m^/1 $
S2 S^ # solids # solids S1 S^ Solids FOG Cr
17,000 13,000 7,870 6,736
15,000 12,000 6,523 6,346
6.25
8.00
6.17
7.89
7.55
6.90
7.9^
7.07
6.79
7.49
7.^2
1.43
1.34
33 3.84 0.98
34 4.15 1.26
Phosphate
POk
TKN mg/1
0.00
0.00
0.15
0.21
0.29
0.20
0.00
0.03
0.00
1.43
0.11
0.20
4.34
0.57
0.41
-------
TABLE 10. FIRST SIXTY WEEKS ANALYTICAL RESULTS
Week
No.
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
Day Volume °
Sampled mgd
12/21/76
12/28/76
1/4/77
1/11/77
1/18/77
1/25/77
2/1/77
2/8/7?
2/15/77
2/22/7?
3/1/77
3/8/77
3/15/77
3/22/7?
3/29/77
4/5/7?
4/12/7?
4/19/77^
4/26/77
5/3/7?
5/10/77
5/17/77
5/24/77
5/31/7?
6/7/77
6/14/7?
6/21/77
6/28/7?
7/5/7?
7/12/7?
7/19/77
.306
.31?
.295
.319 .
.344
.28?'
.355
.295
.286
.305
.28?
.321
.321
.26?
.2?6
.37? -
.283
.272
.269
.312
.295
.316
.304
.336
.313
.241
.313
.376
.343
.36*4
No Data
BOD< Ib/day
Sl
1,465
1,654
1,505
3,908
2,948
2,386
3,23?
3,438
2,296
3,8?4
3,537
3,221
2,584
3,05?
2,303
2,313
S2
816
785
78?
?82
1,248.
771
953
814
935
1,205
1,004
1,185
1,393
1,352
1,452
942
861
1,062
1,40?
869
848
1,151
1,459
S4
128
12?
96
154
20?
136
89
91
86
51
48
59
32
74
48
4?
18
25
40
36
17
32
12
10
15
34
14
14
Suspended
Solids Ib/day
sl
2,456
1,360
6,409
3,630
4,553
4,968
4,61?
3,425
4,871
4,080
3,959
4,451
4,881
4.777
3,216
3,920
3,753
S2
388
315
249
72
668
84
186
145
262
112
203
470
164
843
1,520
1,873
403
635
182
1,039
219
405
643
1,799
S4
299
313
346
215
23?
175
86
74
41
6?
2?
71
90
98
25
61
63
47
18
42
15
38
17
27
29
49
MLSS Sludge
Ibs Age
S-j Days
8,580
9,813
7,621
15,428
11,780
12,448
11,940
12,905
13,940
18,108
15,473
18,935
15,831
21,210
19,766
24,899
27,630
27,279
20,251
24,921
29,54?
25,551
25,273
27,148
26,959
26,151
12
13
11
15
15
16
15
14
15
24
14
18
18
22
24
26
22
32
33
31
22
Chromium
Cr Ib/day
sl
111.0
6?.0
324.
200.
262.
2??.
250
220
2?2
234
249
226
284
266
201
229
226
S2 Sij.
4.08
5.08
2.95
2.66
19.22
1.80 6.22
3-55 3-85
6.2? 1.6?
8.11 4.84
2.04
1.96
.94
1.34
1.83
2.0?
3.08
.9?
1.84
2.60
2.60
1.11
1.93
.98
1.65
.4?
1.10
62.9 1.09
.85
-------
TABLE! 10. CONTINUED
t_n
O
Week
No.
32
33
&
35
36
37
38
39
40
41
42
43
44
45
46
4?
48
49
50
51
52 -
53 .
54
55
56
5?
58
59
60
Day Volume
Sampled mgd
7/26/7?
8/2/77
8/9/77
8/16/77
8/23/77
8/30/7?
9/6/7?
9/13/77
9/20/7?
9/27/7?
10/4/7?
10/11/7?
10/18/7?
10/25/7?
11/1/77
11/8/77
11/15/7?
11/22/7?
11/29/77
12/6/7?
12/13/7?
12/20/7?
12/27/7?
1/3/78
1/10/78
1/17/78
1/24/78
1/31/78
2/7/78
No Data
.363
.325
.366
.342
.28?
.231
.30?
.2?8
.370
.288
.313
.250
.283
.325
.260
.266
.261
.285
.356
.242
.264
.313
.30?
.323
.314
.313
BOD*
Si '
2,516
2,098
1,758
918
1,850
3,060
2,261
2,108
1,898
2,300
2,348
2,366
1,877
2,349
3,284
2,611
2,66?
1,964
1,958
Ib/day
S2
730
861
391
252
737
730
765
834
74?
8?0
846
702
782
1,141
953
1,131
911
908
Suspended
Solids Ib/day
S4
10
11
11
16
10
10
13
12
9
14
21
6
50
18
9
33
21
15
10
26
15
18
10
2?
31
31
Si
2,604
2,971
3,724
3,195
1.972
2,48?
6,688
6,585
6,971
5,798
7,359
2,543
1,6?8
4,4?3
1.748
2,76?
3,892
3,583
2,880
4,30?
S2
109
2,56?
1,774
231
311
524
261
436
2,172
2,378
655
321
229
428
333
415
512
835
650
1,243
S4
38
51
62
185
96
112
184
677
296
75
300
67
113
108
52
35
70
45
59
339
86
42
169
24?
66
162
wisa Sludge
Ibs . Age
Sj Days
26,85?
32,096
29,170
24,538
24,819
26,704
26,001
34,063
28,390
27,691
27,716
29,150
30,754
35,871
38,985
36,909
36,293
36,734
37,340
35,552
34,753
42,803
62,862
37,181
17,057
4?
43
75
38
85
38
45
48
33
41
41
54
71
61
40
60
74
54
25
Or
Si
294
293
369
251
158
195
232
290
264
271
285
288
211
289
329
243
269
259
326
Chromium
Ib/day
S2
5-5
141.0
79.4
22.5
10.5
15.2
6.4
8.8
35-5
93.7
12.3
27.8
22.3
14.1
14.8
19.8
17.9
21.6
28.8
13.1
34
2.82
2.98
2.05
6.85
3.83
1.9
2.8
4.6
2.8
1.7
3.9
1.7?
2.36
2.63
1.30
2.38
1.94
1.50
1.19
1.82
2.64
1.31
0.7?
0.94
1.44
1.57
-------
TABLE 10. CONTINUED
Week
no.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
1?
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Day
Sampled
12/21/76
12/28/76
1/4/77
1/11/77
1/18/77
1/25/77
2/1/77
2/8/77
2/15/77
2/22/77
3/1/7?
3/8/7?
3/15/77
3/22/7?
3/29/7?
V5/7?
4/12/7?
4/19/7?
4/26/7?
5/3/7?
5/10/77
5/17/7?
5/24/7?
5/31/7?
6/7/7?
6/14/??
6/21/7?
6/28/77
7/5/7?
7/12/77
7/19/7?
Pats, oils, and
grease Ib/day
Sl
1,190
833
2,241
1,336
1,754
196
1,8?9
1,361
1,7^5
1,859
1,274
1,950
1,643
1,728
No Data
No Data
1,201
1,455
1,242
No Data
%
80.6
55-0
39-4
77.2
200.8
43.1
45-9
66.4
116.9
?8.4
^5-5
98.0
198.0
66.0
455-5
453.7
540.?
124.9
179-6
23.7
329.6
62.7
138.4
235.2
489.2
34
31.1
16.1
16.1
24.5
54.7
23.6
7.1
13.6
33.7
46.8
27.1
23.7
1?.?
5-2
32.4
8.2
45.8
9.1
Kjeldahl - N Nit
1h/rla.v
Sl
352
342
206
424
234
199
250
241
214
170
20?
23?
s2
157
137
152
168
130
128
111
140
9?
10?
116
169
S4
59-7
66.1
81.?
69.6
72.9
81.2
94.9
81.3
74.4
33-9
42.0
37.2
18.8
rate - N
Lb/day
S4
.62
.22
.41
.21
.45
.74
.91
.25
.26
.06
.28
.26
.19
.54
.94
Total-N
Ib/day
S4
66.3
82.2
70.3
73-8
81.5
95-2
81.4
74.?
34.2
42.2
37.7
19.7
Ammonia-N Temperature
Ib/day °C PH
*1
104
95
6?
121
89
88
62
87
97
120
97
93
9?
81
98
103
122
15?
73
74
100
b4
118.4
96.0
73.9
61.1
43.1
56.2
32.1
66.8
55-2
66.0
73-2
81.?
65.1
62.5
81.2
94.9
75.7
70.3
2?.4
4?.0
24.3
4.6
S3
11
8
9
12
13
12
11
11
13
17
16
17
17
15
21
1?
19
21
20
22
19
25
28
25
26
28
25
29
S3
?.^
7.4
?.?
7.3
7.4
7.3
7.7
7.4
7.5
7.4
7.6
7.3
3.2
7.8
7.2
3.5
7.5
?.?
7.5
7.6
7.7
7.4
8.1
7.7
7.4
7.4
7.3
-------
Ol
.TABLE 10. CONTINUED
no.
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Sampled
7/26/77
8/2/77
8/9/77
8/16/77
8/23/77
8/30/77
9/6/77
9/13/77
9/20/77
9/27/77
10/4/77
10/11/77
10/18/77
10/25/77
11/1/77
11/8/77
11/15/77
11/22/77
11/29/77
12/6/77
12/13/77
12/20/77
12/27/77
1/3/78
1/10/78
1/17/78
1/24/78
1/31/78
2/7/78
Fats, oils, and
grease Ib/day
Sl
No Data
1,386
1,418
No Data
1,038
1,408
1,382
1,142
1,153
1,413
No Data
1,303
1,058
850
1,212
1,788
1,483
862
1,624
1,501
S2
13.6
745.6
488.0
49.9
64.7
62.
64.
26.
133.
243.
62.6
88.0
62.4
78.7
79-3
146.2
74.3
185.9
201.6
190.6
S4
11.5
17.6
27-5
25.4
21.6
17.0
3.8
10.7
6.8
43.2
18.3
13.4
177.0
19.0
3.3
15-1
15-5
13.1
36.6
0.8
22.0
4.7
10.2
13.7
6.0
8.9
K jeldahl -
Ib/dav
Sl
221
241
211
248
141
261
236
225
195
209
216
202
192
172
274
222
240
222
188
S2
121
150
123
91
141
128
142
135
112
136
149
121
117
170
133
156
144
136
N Nii
34
10.0
13.6
11.9
16.0
7.5
15-9
14.4
14.8
13.5
17-5
8.8
42.5
43.4
10.2
30.0
23.9
12.6
14.9
9.1
26.4
9.7
17.2
42.3
36.7
43.9
;rate - N Total-N
Ib/day Ib/day
4.66
2.63
5-71
51-51
15.02
31.79
39.29
33.44
5.42
5.31
1.60
0.18
0.20
0.38
0.26
7.14
24.4?
0.20
0.25
0.20
10.52
5.84
0.08
0.26
14.7
16.2
17.6
67.5
22.5
47-7
53-7
48.2
18.9
22.8
10.4
42.7
43.6
10.6
30.3
19.7
39.4
9.3
26.7
9.9
27.7
48.1
36.8
44.2
Ammonia-N Temperature
Ib/flav °G PH
Sl
112
127
107
49
72
62
97
81
99
96
94
98
131
54
82
112
74
65
115
71
34
2.4
2.7
2.1
1.1
3.4
1.0
2.6
1.4
2.8
6.5
6.3
2.7
37.8
29.8
5.0
12.7
19.6
6.4
5-9
9.1
15.4
9.7
14.1
41.8
41.9
42.3
S3
26
27
26
28
25
26
23
25
22
22
16
17
17
16
16
15
15
15
15
16
15
16
S3
6.6
6.8
6.6
6.8
7.6
7.4
6.6
7.5
7-3
6.7
6.6
7.1
7.2
7.0
7.2
7.3
7.4
7.5
7.4
7.1
7.2
7.4
7.1
7.1
7.0
7.3
-------
Discussion of graphs of analytical results.
The results as depicted in the graphs indicate operational features
and dependent variables that have occurred during the three periods. Com-
ments upon each graph follow:
Figure 14. BOD vs. Week; This graph indicates that biological stability or
consistency was not established until about the 20th week of opera-
tion. The overall results indicate a BOD of 10 to 20 Ib/day
(^ to 8 mg/l) is readily achieved. The special test periods do not
indicate any abnormalities.
Figure 15. pH and Temperature vs. Weekt A notable indication in this graph is
that the plant was put into operation during a very cold period
which was generally much colder than the winter of 19??-?8. This
curve might seemingly indicate that the reason for the long break-
in period was the cold weather, but other factors such as opera-
tional problems in the primary and secondary and overall plant
break-in problems were equally significant.
Figure 16. F/M vs. Weekt This curve shows that the design F/M of 0.06
was not reached until about the 20th week of operation. The best
BOD efficiency is seen to occur during the lowest F/M loading
periods.
Figure 1?. Sludge Age vs. Week; This curve indicates that the sludge age is
Figure 38.
over 30 days which insures the sludge to be aerobically digested.
MISS, MLVSS, and SVI vs. Weekt This curve indicates a very good
set of values for SVI, but it also shows that the MISS is much
higher than designed or expected.
Figure 19 . Suspended Solids vs. Weekt This graph indicates a higher than ex-
pected amount of suspended scOMs in the effluent. The very high
MISS or solids in the aeration unit can be imagined to be the
cause, but other reasons including final clarifier upset, erratic
sludge return, and inability to waste excess sludge were respon-
sible in part.
Figure20. Nitrogen vs. Week; The nitrogen plots indicate a trend toward
consistent nitrogen removal which seems to be independent of tem-
perature or pH. The erratic values indicate a need for refine-
ment in operational procedures, but no change in the design.
Figure 21. Ammonia vs. Weekt This curve indicates a potential for high am-
monia removal. It also seems to indicate that nitrification and
denitrification maximizes during the summer or warm water tempera-
ture period.
Figure22. Fats, Oils and Grease vs. Weekt This plotting indicates erratic
primary and secondary removal, but a. very consistent overall re-
moval .
53
-------
10000
WINTER
SPRING I SUMMER
FALL | WINTER
1000
(0
100
O
DO
10
BREAK-IN
PERIOD
BIOLOGICAL
STABILITY
10
20
30 40
WEEKS
50
60
Figure lit.,
BOD,- levels in paw wastewater, after primary
treatment, and after total treatment.
First sixty weeks.
54
-------
100C-
WINTER I SPRING I SUMMER | FALL | WINTER I
1 _________ L..._l
...... J ________
0 10 20 30 40 50 60
WEEKS
Figure 1$. Temperatare and pH In the carrousel.
PIrat sixty weeks.
55
-------
100
0.01
30 40
WEEKS
Figure 16.
Food to microorganisms ratio and relation-
ship to final BOD^. First sixty weeks.
56
-------
100
I
UJ
a
UJ
O 10
O
1.0
~~r i i—r
10
20
30 40
WEEKS
50
I.
60
Figure I?. Average age of suspended solids In the car-
rousel. First sixty weeks.
57
-------
100,000
10,000
E
i
Q
O
Q
UJ
Q
z
UJ
Q.
(/) 1,000
V)
X
uj 100
Q
UJ
5
UJ
O
Q
10
(f)
7 T
7
10
20
30 40
WEEKS
50
_L
60
Figure 18. Suspended solids in the carrousel and sludge
volume index. First sixty weeks*
58
-------
10,000
I
Q
LU
O
z
UJ
Q.
V)
1,000|- —
100
WEEKS
Figure 19* Suspended solids in raw wastewater; after
primary treatment; and after total treat-
ment. First sixty weeks.
59
-------
100
•o
^
111
CD
O
QC
10
7
TKN
TKN
1.0
<<\;
A I
fM'
TOTAL N-S4~-
I * ft
'i. \.. PAH
NITRATE N-S4
'\
"A I
10
L _ L 1 J J
20 30 40 50 60
30 40
WEEKS
Figure 20* Nitrogen in raw wastewater; after primary
treatment; and after total treatment.
First sixty weeks.
60
-------
100
O
<
0.1
_L _ J
10 20
7
30 *0
WEEKS
[ _L_ J
50 60
Figure 21. Ammonia nitrogen in raw wast ©water; and after
total treatment. First sixty weeks.
61
-------
10,000
1,000
(0
•o
I
HI
UJ
DC
o
100
30 40
WEEKS
50
60
Figure 22. Pats, oils, and grease in raw waste-water;
after primary treatment; and after tfital
treatment. First sixty weeks.
62
-------
Figure 23. Chromium vs. Week; The characteristics of this plot are similar
to the previous Fats, Oils and Grease curves. Content in the
final effluent is low and consistent.
Figure BOD vs % Frequencyt This set of plots indicates good removal and
2k, 25 or satisfaction of BOD as shown by the effluent BOD at S^. The
results would be better if the solids were filtered from the
samples prior to analyzing for BOD. The efficiency is seen to be
the same for the two special test periods. The variations are
about what they would be expected to be.
Figure Suspended Solids vs. % Frequency; The primary significance in
26, 2? this set of plots is the relatively poor removal of solids in the
secondary clarifier,, The MLSS in the aeration unit is much higher
than the design. This was due to a combination of reasons which
will ultimately be corrected, including inability to waste excess
sludge on a set schedule because of clogging of return pumps.
This difficulty also contributed to the high solids content in
the final effluent. The secondary clarifier was subject to set-
tling upsets and short circuiting assumed to be due to changes
which the unit could not handle. The overall plant efficiency is
over 90^ and does not vary greatly with seasonal changes.
Figure SVI vs. % Frequency» The consistent value of less than 100 in-
28, 29 dicates a very stable sludge condition. The sludge condition
changed somewhat from the first test period to the second but the
amount of MLSS also changed appreciably.
Figure Suspended Solids (% Volatile) vs. % Frequency; This set of plots
30, 31 did not indicate anythdng significant except to show the great
variation in the primary effluent and the consistently low MLVSS
content in the aeration unit. The low volatile percentage can be
assumed to be due to c-arryover of suspended solids from the primary
section.
Figure Nitrogen vs. % Frequency; These plots indicate one of the most
32, 33 important determinations of this demonstration project, the ability
of the secondary treatment to remove over ?0# of the total nitrogen
summer or winter. During the summer more nitrate and less ammonia
occured in the effluent than during the winter test period, but
the overall nitrogen removal for the total plant was greater in
the winter 90$ to $4$. The erratic results were due to operational
trials, changes, and adjustments, but the overall ability to remove
substantial amounts of :nitrogen can be seen. More work must be
done on optimizing the loperation through instrumentation in order
to eliminate operator control and error.
Figure TKN vs. % Frequency t This set of plots is very similar to the total
34, 35 nitrogen plots, Figures 15 & 24. When nitrates are present the
total nitrogen includes them, as in Figure 20, but they are not
included in the TKN. The TKN includes Mj. It does not, by itself,
indicate the degree of nitrification.
63
-------
1,000
0.1
10
20
30 40
WEEKS
50
60
Figure 23. Chromium in raw wastewater; after primary
treatment; and after total treatment.
First sixty weeks.
64
-------
10,000
FT
|
Summer
Test Period
1,000
(0
•o
.0
O
CD
10O
10
1.0
-* *
" MEAN 2100
V
MEAN 740
2 5
Figure
-'fe « « MEAN 12
I L i I U I_LLJ_
5 10 30 50 70 90
98
levels in paw wastewater; after pri-
t?I2twnt; and after t^otal treatment,
65
-------
10,00
1,000
(0
O
CO
10
i.o
T T
Winter
Test Period
Tr T FT
* *
5 10
30 50 70
90
9
Figure 2$.
Frequency Of Occurrence, %
BOD,- levels in raw wastewater; after prim-
ary treatment; and after total treatment.
66
-------
1000
1.0
10 30 SO 70 90
Frequency Of Occurrence,
98
Figure 26. Suspended solids levels in raw
wastewater; after primacy treat-
ment; and after total treatment
67
-------
10,000
10
10 30 50 70
Frequency Of Occurrence, %
9O
98
Figure 27. Suspended solids levels in raw
wastewater; after primary treat-
ment; and after total treatment.
68
-------
120
X
Ul
Q
100
80
§
Ul
O
Q
60
40
T
Summer
Test Period
1 T
MEAN 84
0.1
5 10 SO 80 90 95 98 99 99.5
Frequency Of Occurrence, %
Figure 28. Sludge voluwe ladex for carrousel activated sludge
69
-------
120
O)
i
X
UJ
Q
5 80
UJ
g
UJ60
O
O
40
1 T
Winter
Test Period
MEAN 55 »>"
d L
20
so
L.LU. .1
80 90 95 98 99
Frequency of Occurrence, %
Figure 29. Sludge volume index for carrousel activated sludge.
70
-------
0.1
Figure 30.
15 20 50 80 90 95 98 99
Frequency Of Occurrence, %
Volatile suspended solids levels after primary
treatment, and In the carrousel.
71
-------
Figure 31.
L.U_LL
1 5 10 50 80 90 95 98 99
Frequency Of Occurrence, %
Volatile suspended solids levels after* primary
treatment, and in the earrousel.
72
-------
1,00
80 90
Frequency Of Occurrence,%
98
Figure 32. Total nitrogen levels IB raw waste-
water; after primary treatment; and
after total treatment.
73
-------
1000
1.0
Frequency Of Occurrence, %
Figure 33. Total nitrogen levels in raw waste*
water; after primary treatment;
and after total treatment.
74
-------
1,000
(0
^s" 100
LU
o
O
DC
I-
X
<
Q
10
1.0
E~T~T—T
1
Summer
Tesl Period
T f j I
MEAN 11
1
98
2 5 10 20 40 60 80 90
Frequency Of Occurrence - °/0
Figure 3lj.. Kjeldahl aitrogen levels la paw waste-
water; after primary treatment; and
after total treatment.
75
-------
1,000
1.0
2 5 10 20 40 60 80 90
Frequency Of Occurrence -%
98
Figure 35« Kjeldahl nitrogen levels la raw
wastewater; after primary treatment;
and after total treatment.
76
-------
Figure Ammonia vs. % Frequencyt This graph indicates very good removal
36, 37 or conversion of NHo. It also indicates better efficiency during
the summer test period.
Figure Fats, Oils and Grease (FOG) vs. % Frequencys This plot shows con-
38, 39 sistency, good removal, and low effluent concentration.
Figure Chromium vs. % Freq uency \ The most important observation in this
40, 41 set of plots is the consistently high removal efficiency and the
low final effluent concentration.
77
-------
100
MEAN 95
>.
CO
^
£
i
10
O
FT i r
Summer
Test Period
1 T
TT1
2 S 10 20 40 60 80 90 98
.Frequency Of Occurrence -%,.
Figure 36. ammonia levels in raw wastewater
and after total treatment.
78
-------
1,000
100
(0
10
z
o
1.0
0.1
Winter
Test Period
rr~TTT
10 20
40
60
80
98
V *»» -TV
Frequency Of Occurrence -%
Figure 3?. Ammonia levels in raw wastewater,
and after total treatment*
79
-------
10,00
1.0
2
LJ_i LLLLL L
98
5 10 20 40 60 80 90
Frequency Of Occurrence - %
Figure 38. Pats, oils, and grease levels in
paw wastewater; after primary treat-
ment; and after total treatment.
80
-------
10,000
1,000
<0
•o
.Q
I
HI
C/>
<
LU
DC
O
o
<
.ILL I -
100
5 10 20 40 60
Frequency Of Occurrence -
Figure 39. Pats, oils, and grease levels in raw
waafeewater; aftep primary treatment;
and after total treatment.
81
-------
1,000
I Summer
Test Period
1.0
10
Frequency Of Occurrence - %
figure UO. Chromium levels in raw wastewater;
after primary treatment; and after
total treatment, expressed as Cr.
82
-------
1,000
100
eo
O
O
cc
X
O
10
1.0
i i r
Winter
Test Period
TTT7
T~ r
MEAN 230
20
60
80 90
1U
-------
SECTION 8
CONCLUSIONS AND EVALUATIONS
CONCLUSIONS AS TO PARAMETER REMOVALS
The first objective of this demonstration grant was to determine the
effectiveness of this treatment system in finite terms. One of the principal
further objectives was to determine the effect of cold weather upon bacterial
activity in the secondary portion. The data in tables 8 and 9 has been sum-
marized to show the total pollutant removal efficiency of this wastewater
treatment plant while operating under summer conditions as well as winter
conditions. This summary follows:
TABLE 11. AVERAGE PERCENT OF POLLUTANT REMOVAL
TOTAL TREATMENT* SUMMER AND WINTER TEST PERIODS
% Removal
Pollutant
BOD5
Suspended solids
Nitrogen- total
TKN
Ammonia
Fats, oils and grease
Chromium
Summer
99-1
80.9
94.7
94.1
96.4
98.8
99-0
Winter
97.6
84.1
83-5
87-4
74.6
99.0
98.8
*0n basis of differences between samples taken at Sj_ and
It is evident from this table that winter operating conditions did re-
duce carbonanceous and nitrogenous biological activity noticeably but substan-
tial reduction continued to occur.
BOD Remo v^als
Cold weather has a substantial effect upon many biological wastewater
treatment systems in lowering the efficiency of BOD removal. In this study
84
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the average .BOD reduction during winter was only slightly less than in summer.
In addition, Table 9 reveals that single-digit results in mg/1 were frequently
achieved in winter, thus indicating excellent resistance by the carrousel de-
sign to atmospheric conditions well below freezing.
Table 11 shows in excess of 97% removal of BOD regardless of seasonal
conditions. The average residual BOD is shown by analysis to be on the order
of 6 mg/1. This is one-fifth of the unofficial BAT standard. Obviously this
wastewater treatment plant is very effective in reducing biological oxygen
demand.
Suspended Solids Removal
Short of an actual freeze low temperatures would not be expected to be
much of a deterrent to removal of suspended solids. Actually the record
shows the removals to be a little better in winter than in summer, but exa-
mination of the data reveals that temperature was not a factor in the inci-
dence of residual suspended solids as discharged.
Table 12 shows suspended solids to be in excess of the unofficial BAT
requirements. Terminal removal is dependent upon the efficiency of the final
clarifier. Obviously some additional fine tuning will be required but com-
pliance seems to be attainable.
Nitrification - Denitrification
The data shows that the carrousel is capable of supporting nitrifying
and denitrifying bacteria. The former converts nitrogenous compounds to
nitrates, and the latter converts nitrates to free nitrogen. Analytical re-
sults reported in Table 8 and Table 9 bear this out. Some TKN removal occurs
chemically in the primary section. The tables clearly show that ammonia
nitrogen and organically bound nitrogen entering the carrousel at S£ were
substantially reduced in the ditch, more in summer than in winter. Table 9
also reveals that on some days during winter operation very low concentra-
tions of NH3-N and TKN did occur at 84, indicating that lower average nitri-
fication activity in winter may have been more attributable to occasional in-
cidence of an unknown form of toxicity than temperature.
Conversion of nitrates to nitrogen is not only an interesting and per-
haps unique feature of this system but it also has broad implications in the
whole field of wastewater treatment. Support of denitrifying bacteria seems
to be somewhat more difficult than that of the nitrifying strain. Additional
study toward establishing a more stable environment for these organisms would
certainly be worthwhile. Denitrifiers were rather late in developing during
the summer period but they were extremely active and efficient during the^
winter period Later on, after this grant project was completed, the denit-
rifiers were adversely affected for a time, but they have now returned. They
may have been subjected to some form of chemical toxicity, or perhaps the
balance of aerobic/anoxic conditions was not agreeable. Work is continuing
to gain further insight.
85
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Fats, Oils and Grease Removal
As with suspended solids the removal of fats, oils and grease would
not seem to be very temperature dependent, and the results are consistent
with this. Average removal was actually a little higher in winter than in
summer but it is not possible to fix to this any real significance .
In comparison with unofficial 1983 BAT levels the average results are
better than required, with residual pollutant in the effluent approximately
of that allowable by BAT. 99$ removal is achieved.
Chromium Removal
Chromium is probably the most important parameter, from the point of
view of removal, of any of the components of tannery effluent. Controversy
exists as to the relative toxicity of tannery chromium discharged. Actually
it exists entirely in the trivalent form and as such is highly insoluble at
pH's encountered in a biological treatment system, but many investigators are
skeptical and suspect that a portion may exist as or be converted to the hexa-
valent form which is highly toxic. The existence of chromium .in this system
at the residual level after primary treatment has never poisoned the bacteria
in the secondary or limited biological activity in any way, thus indicating
rather conclusively that it is all trivalent, virtually insoluble, and benign.
The analytical data shows a high degree of removal, 99% on the average,
both summer and winter. In terms of kilograms discharged per kilogram of raw
pelt the average amount discharged is within the BAT requirement.
SYSTEM EVALUATION AND DISCUSSION
The proposal for this grant states on page 20, Part IV-^te, Sampling
and data collection procedures, that methods for evaluating the results of
the project will consist of:
a. Evaluating the character of the final effluent in terms of attain-
ment of BAT requirements.
b. Fixing the cost of operation while producing effluent at BAT
levels in terms of:
Cents per foot of finished leather product .
Gents per pound of finished leather product.
Cents per pound of BOD plus GOD removed.
Cents per pound of suspended solids removed, compacted and
placed at final destination.
Cents per pound of nitrogen removed.
86
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The grant amendment dated August 23, 1976, added other means of eval-
uating the results. These are:
Page 5A, item 3C
Include the cost in cents per 1,000 gallons treated.
Page 5A, item 5
The grantee shall include a section which compares the demonstrated
processes with other processes used for the same or similar purposes
in the tanning industry and describe what changes in design or cost
would be expected when applying the demonstrated technology to a
typical cattle hide tannery. Specific items to be addressed ares
a. comparison on a cost-effective basis of the LectroGlear with
available information on conventional primary treatment or dis-
solved air flotation being utilized by the industry, or with the
possibility of no primary treatment.
b. comparison of the performance and other data on the carrousel
with available information on the unit in Oisterwijk, Nether-
lands treating tannery wastewaters.
c. based on the demonstrated design criteria and available infor-
mation, make a preliminary design and cost estimate for install-
ing the system at a typical cattle hide tannery in the U.S. to
meet the 1983 guidelines.
In this section of the report the above specified means of evaluation
will be dealt with in the order of listing, with the exception of item 5c,
which will be detailed in a separate section. See Section 9-
ATTAINMENT OF BAT REQUIREMENTS
The BAT requirements for 1983 (unofficial) are compared in Table 12
with the results obtained during thV summer and winter operating periods of
the Winchester project. Compliance is achieved in almost every category ex-
cept suspended solids, TKN in the winter, and fecal coliforms. The latter
can be controlled only by disinfection. Ghlorination has not been provided
as a function of the treatment facility, Undoubtedly some chlorine genera-
tion occurs as a result of electrolysis in both the coagulation cell and the
flotation basin but this was not evaluated. It may account for the lower in-
cidence of coliform colonies during the first test period when electrolytic
activity was greater. It is interesting to note that the average level of
.1*0 kg of TKN per 1,000 kg of raw pelt in the treated wastewater during win-
tertime conditions, while in excess of BAT, represents an 87% removal of TKN
from the raw wastewater.
87
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TABLE 12. COMPARISON OF WINCHESTER EFFLUENT WITH
BEST AVAILABLE TREATMENT STANDARDS FOR 1983 *
oo
CO
BAT BAT Winchester
average of daily
maximum/day _ values for summer conditions
30 consecutive days /£c ciays)
Pollutant
BOD^ **
Total suspended solids **
Chromium **
Oil and grease **
Sulf ide **
TKN **
Fecal Coliforms/100 ml
PH
3.20
3.60
0.12
1.26
0.012
0.62
400
6.0-9.0
1.60
1.80
0.06
0.63
0.006
0.31
no std.
no std.
max/day
0.4?
12.34
0.14
3-25
-
0.59
660
6,5-7-6
ave/day
0.29
4.77
0.06
0.34
-
0.31
-
Winchester
winter conditions
(25 days)
max/day
0.86
9.24
0.07
1.63
-
1.29
7,000
6.8-?.6
ave/day
0.36
3-65
0.06
0.19
-
0.40
-i
* Federal Register Volume 39 Number 69 April 9, 1974. Promulgated but remanded. Par42553
** Unit is kg/1000 kg raw pelt.
-------
COSTS OF OPERATION
One of the study objectives was to -determine the operating costs of
producing treated effluent at BAT levels in terms of cents per foot of fin-
ished father product, cents per pound of finished leather product, cents per
pound of BOD removed, cents per pound of suspended solids removed, compacted
and placed at final destination, cents per pound of nitrogen removed, and
cents per 1,000 gallons of wastewater treated.
Operating costs for the 12-month study period weie as follows:
Plant personnel $46,860.68
Chemical supplies and electricity — 78,301.20
Repairs and equipment ----____ 8,423.00
Total $133,584.88
Production during the 12~month period was:
Skins produced (dozen) 58,466
O
Skins produced (ft ) 5,846,600
Gents per Foot of Finished Leather Product
The cost of producing BAT level effluent per foot of finished leather
product is determined as follows:
Operating cost/year $133,584.83
Skins produced (ft2) 5,846,600
Cost per square foot of product - - - $.0228
Cents per Pound of Finished Leather Product
Cost of the BAT-level effluent per pound of finished leather product
is determined as follows:
Operating cost/year $133»584.88
Skins produced (dozen) 58,446
Average weight per dozen (ib) - - - - 24
Total weight (ib) 1,402,?04
Total cost per pound $0.095
Cents per Pound of BOD Removed
Cost of removing BOD is determined as follows:
Operating cost/year $133,584.88
Operating days/year 250
Operating cost/day $53^
89
-------
BOD removed/day (ib) 2,050
Cost/lb BOD removed $0.26
Cents per Pound of Suspended Solids Removed, Compacted, and Placed at
Final Destination
Cost for removing suspended solids, compacting them, and placing them
at their final destination is determined as follows:
Operating cost/day ------------ $53^
Suspended solids removed/day (ib) - - - - 2,39^
Gost/lb suspended solids removed ----- $.22
Gents per Pound of Nitrogen Removed
Cost for removing nitrogen is determined as follows:
Operating cost/day ------------ $53^
Nitrogen removed/day (ib) -------- 272
, Gost/lb nitrogen removed --------- $1.96
Cents per 1,000 Gal, of Wastewater treated
Cost per 1,000 gal of wastewater treated is determined as follows:
Average daily flow (gal) 301,000
Operating cost/day ------------ $53^
Gost/1,000 gal wastewater treated - - - - $1.77
OPERATING COST OF MIGROBUBBLE GENERATION BY ELECTROLYSIS, DISPERSED AIR,
AND DISSOLVED AH.
Elsewhere in this report it is stated that the LectroGlear electroly-
tic cell, as a primary source of microbubbles, was discontinued for two rea-
sons; an inordinate amount of difficulty was encountered with maintaining
electrodes in the coagulation cell operational, and clear evidence was estab-
lished that the electrolytic generation of microbubbles could not compete
cost-wise with dispersed air generation.
Electrolysis
The cost of operation of the LectroGlear electrolytic cell, the ori-
ginal principal LectroGlear microbubble generator is determined as follows:
Design amperage requirement ------- 2,900
Design voltage requirement (DC) ----- 6
Kilowatts required per hour ------- 17.^
90
-------
Power cost per kilowatt hour $0.035
Cost of power per hour . $0.609
Hydraulic flow rate (gpm) JQO
Cost per 1,000 gallons $.034
Dispersed Air
The cost of operation of the dispersed air generator is determined as
follows!
Design power requirement (hp) 2
Kilowatts per horsepower --------- 0.746
Power cost per kilowatt hour ------- $0.035
Cost of power per hour $0.052
Hydraulic flow rate (gpm) 300
Cost per 1,000 gal. . $.003
Dissolved Air12
The estimated cost of operation of dissolved air flotation for this
application, 300 gpm throughput with 50% recirculation for microbubble forma-
tion is calculated as follows:
Design rate of flow (gpm)- -------- 300
Recirculation rate - 50% (§pra) ------ 150
Back pressure for air solubilization (psi) 60
Required pump HP------------- 7
Kilowatts required per hour 5«2
Power cost perKWH $0.085
Cost of power per hour ---------- $0.182
Hydraulic flow rate (gpm) 300
Cost per 1,000 gallons $0.010
These calculations show that the cost of electrolytic generation of
microbubbles is on the order of eleven times that of dispersed air genera-
tion. Considering this, along with less than adequate electrode reliability,
leads to rejection of the electrolytic concept as a principal source of en-
couragement to flotation. Likewise the calculated cost of operation of a
system designed to provide microbubbles by means of dissolved air for floe
flotation is in excess of the cost determined by actual operation for dis-
persed air.
91
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TABLE 13. COMPARISON OF COSTS OF OPERATION OF SYSTEMS TO PROVIDE
MICROBUBBLSS FOR A FLOTATION SYSTEM
FOR SUSPENDED SOLIDS SEPARATION
Cost of operation
Microbubble per
generation mode 1,000 gals treated
LectroClear
Dissolved Air
Dispersed Air
$.034
$.010
$.003
CONSIDERATION OF THE POSSIBILITY OF NO PRIMARY TREATMENT
The possibility of elimination of primary clarification, and depen-
dence upon a biological treatment system plus a final clarifier only has been
considered. The existence of a relatively large amount of chromium in the
non-clarified wastewater as a substance potentially toxic to activated sludge
bacteria has been a deterrent to experimental by-pass of the primary section.
Other toxic chemicals which may be absorbed in the agglomerated precipitates
in the primary section and removed there are suspected of being present in
the raw wastewater also, which could interfere with bacterial activity in the
carrousel, although these were not identified in this study. Chromium and
alumium hydroxides formed by pH adjustment to 7.5 to 8.5 to remove them, as
well as to provide agreeable environmental conditions for bacteria in the se-
condary, are gelatinous precipitates which do not rapidly settle to a reason-
ably compact bottom sludge layer. These facts, and the high incidence of
emulsified fats and oils encountered in the waste stream, led to a laboratory
bench scale testing decision in the design stage that removal of the suspend-
ed solids introduced to the system would best be removed by flotation. These
considerations, in addition to the compaction feature provided by microbubbtes
continuously rising, raising and dewatering the sludge blanket atop the flo-
tation basin, haxe adequately demonstrated the desirability of maximum separa-
tion of suspended solids in a primary clarification section prior to acti-
vated sludge treatment.
COMPARISON OF THE PERFORMANCE OF THIS CARROUSEL WITH ONE AT OISTERWIJK,
NETHERLANDS13
A full scale carrousel has been in operation at Oisterwijk, Nether-
lands since 1973 treating tannery wastewater. The tannery is in the category
1 classification, chrome tan-hair burn, and is of medium size, processing not
much more raw hide weight (55»000 Ib/day) than the Winchester tannery
(<^3i200 Ib/day green salted shearlings). Water usage at 0.475 mgd is in
direct proportion on a green hide or skin weight basis to the volume used at
Winchester (.350 mgd). Following is a table showing waste loadings to the
92
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Oisterwijk carrousel as well as the Winchester carrousel, and the degree of
removal of pollutants affected significantly by secondary treatment, BOD,
NH«j-N and total N.
TABLE 14. COMPARISON OF CABROUSEL TREATMENT EFFICIENCIES
WINCHESTER, N. H. vs. OISTERWIJK, NETHERLANDS
Treatment
plant
Winchester BOD5
Oisterwijk BOD5
Winchester-NH-^-N
Oisterwijk-NH3-N
W inches ter- 1 otal-N
Oisterwijk-total-N
Influent
mg/1
31?
1,100
32
264
10?
408
Effluent
mg/1
6
20
5
248
12
2?0
Removal
%
98
98
84
6
89
34
The loadings to the carrousel at Oisterwijk are far greater than to
the carrousel at Winchester as shown above. This may be due to removal of
BOD and nitrogenous material in the Winchester primary section, whereas it
is the understanding that the Oisterwijk treatment plant does not have pri-
mary coagulation and clarification.
Comparison of the efficiency of each in terms of removal of parameters
clearly shows superiority of the Winchester operation. Further proof of this
is demonstrated by quoting from a recently issued DRAFT of an E.P.A. develop-
ment document for the leather tanning and finishing industry!3 Investigators
who prepared this document state, on lines 6863 through 6866, "This (analysis
of data) indicates that this (Winchester) activated sludge system produced
better results than the Netherlands (Oisterwijk) application, including de-
monstration of insensitivity to winter temperatures in removal of carbonace-
ous oxygen demand (BOD5) and nitrogenous oxygen demand (ammonia) by nitrifi-
cation ."
The Oisterwijk application, according to analytical data available,
was not very effective in nitrification and denitrification. Experience at
Winchester at times other than the demonstration periods has shown that de-
nitrification in particular is a sensitive process. It is also possible
that the Oisterwijk facility was not being operated with any emphasis upon
nitrification-denitrification at the time the above data was recorded. More
operating background and understanding is needed to further establish relia-
bility at high levels of nitrification-denitrification.
93
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SECTION 9
APPLICATION OF THE SYSTEM
TO
CHROME-CATTLEHIDE AND VEGETABLB-CATTLEHIDE
TANNERIES
CONSIDERATION AND COMPARISON OF PROCESSES
Three of the seven categories of tanneries relate to full-scale cattle-
hide processing - including hair removal, tanning, coloring and fatliquoring,
and finishing. The three categories are cattlehide tanneries that (l) pulp
hair and chrome tan, (2) save hair and chrome tan, and (3) save hair and
vegetable tan.
Few if any chrome tanneries save hair. More and more the mode has been
to soak, wash, and hair-burn using strong sodium sulfide liquors. Most tan-
neries operating this way reclaim sulfide liquors and separate pulped hair
solids from those solutions, directing the solids to land-fill, thus keeping
as much as possible of those materials out of the waste stream. Similarly
systems have been developed by most chrome tanners to conserve chromium by
precipitation and reuse or by recycling of chrome tan liquors, and most are
conscious of the need for water conservation, not only from the point of view
of initial cost, but in consideration of the effects of wasteful dilution, and
the hydraulic load cost of disposal and sewerage treatment.
In a different but similar manner most vegetable tanneries employ a
hair save process. This system uses much less sulfide and produces a valua-
ble by-product in the form of cattle hair. Not unlike chrome tanners, vege-
table tarmere have been able to reduce or eliminate some process steps which
formerly required much water.
The net result of these in-plant activities has been to reduce high
potency waste liquors to levels which are not so different from those encoun-
tered at the shearling tannery. Because a shearling tannery is not typical,
since it does not process cattlehide and has no beamhouse, transfer of identi-
cal wastewater treatment technology is not possible. Nevertheless, very real
similarities do exist in the nature of the respective tannery discharges,
which lead to speculation that adaptations should be explored.
94
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COMPARISON OF WASTEWATERS
, v, t0 rather definitely establish the similarity the following
table of typxcal analyses of wastewater from these A, G. Lawrence tanneries,
all of which are considered to be more or less representative of complete
tanning operations in their respective categories are presented.
TABLE 15. TYPICAL TANNERY WASTEWATER ANALYSES
Parameter
BOD-
Suspended solids
Total solids
Calcium-Ca
Fats, oils, greases
pH
Chromiuni-Cr
Ammonia-N
TKN-N
Volume-mgd
Raw hide or pelt Ib/day
Water usage-gal/lb hide
Category 1
Cattlehide
Chrome tan-pulp hair
South Paris, Maine
mg/1
1,630
2,?18
5,620
649
580
10.9
18?
14
126
0.8
130,000
6.1
Category 3
Cattlehide
VegtawsERenair
Hazelwood, N.C.
mg/1
686
1,080
5,314
550
201
9.9
-
73
179
0.3
52,000
5.8
Gate, - .y 7
Shearlings
Chrome tan
Winchester
mg/1
812
1,150
14,000
400*
450
5.1
99
32
75
0.3
41,500
6.9
*Added at treatment plant
Examination of this table shows that there is a remarkable similarity
in the nature of the wastewater from each. The volumes are not the same, of
course, but the significant differences in pollutant strengths are on the
order, for the most part, of about 2X. Total volume is considerably greater
for the side leather tannery since this is a function of capacity. The
figure of 14,000 mg/1 for total solids in the Winchester column reflects the
very large comparative amount of curing salt in and on a raw pelt or entrapped
in the wool, and the use of long brine floats in paddle pits while processing
shearlings as opposed to short brine floats in drums for hides.
It seems in order then, to take the stance that this treatment system,
with some modifications, is suitable for any tannery. One of the require-
ments of this demonstration project is to prepare a preliminary design and
cost estimate for a system suitable for a. typical U.S. cattlehide tannery to
meet 1983 BAT guidelines. This exercise will include a system for a chrome
95
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tan-pulp hair category 1 tannery, and a system for a vegetable tan-save hair
category 3 tannery. Since A. G. Lawrence Leather Company operates and has
intimate knowledge of fairly typical tanneries processing cattlehides in both
of these categories those tanneries will comprise the basis for the designs.
Comparison of parameters, as in Table 15» seems to impart validity to
the statement that the only apparent differences between wastewater a treat-
ment facility suitable for a hide tannery, and a shearling tannery, would be;
(l) size, (2) provision for initial sedimentation to remove some of the heavy
beamhouse and tanhouse solids before intermixing the two streams and (3)»
proper built-in precaution, particularly in the case of the chrome-pulp hair
tannery, to consistently maintain the pH in the mixed beamhouse-tanhouse
liquor above 8.5 to prevent evolution of hydrogen sulfide as an obnoxious
and perhaps potentially lethal gas. These considerations are incorpoxated
in the designs.
96
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PRELIMINARY DESIGN AMD COST DEVELOPMENT FOR A
WA3TEWATSR TREATMENT PLANT FOR A CHROME
TAN-PULP HAIR CATEGORY 1 GATTLSHIDE TANNERY
This exercise is addressed by expanding the detailed information on
the Winchester treatment plant components as presented in Section 3 of this
report, and cost information for the complete system presented as Appendix B.
Two reports, entitled "Supplemental Report on Combined Wastewater Treatment
Facilities, Paris Utility District, South Paris, Maine" by Whitman and Howard,
Inc. Boston, Mass, and the other, "Activated Sludge Treatment of Chrome Tan-
nery Wastes" by A. C. Lawrence Leather Co., South Paris, Maine, F.W.P.C.A.
Publication ORD-5 are used for background information in developing the
chrome-tan pulp hair preliminary design. Co'sting of components is estimated
by comparing flows and parameter loadings at South Paris and Winchester where
applicable, and arriving at a reasonable estimation. No attempt has been
made to provide engineering designs or obtain equipment or construction con-
tractors bids for any item. Costing of concrete construction has been esti-
mated by examination of costs presented in the above documents, and has been
determined to be about $8.00 per cubic foot of total tank volume, after up-
dating 1974 and 19?6 prices by compounding at 8$ per year.
See Figure 42 for schematic diagram.
97
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CONSTANT
HEAD BOX
DISPERSED AIR
COAGULATION
ALKALINE FLOW
EQUALIZATION TANK
ALUM
CELL
BUBBLE
CLASSIFIER
BEAMHOUSE FLOW
CLARIFIER
QC
Ul
z
ACID FLOW
EQUALIZATION TANK
TANHOUSE
CLARIFiER*
00
RIVER
I FINAL
CLARIFIER
Figure L.2.
Schematic Diagram of Proposed Wastewater Treatment Plant
for a Category 1 Chrome Tan Pulp Hair Cattlehide Tannery
-------
Basic Design Parameters - Chrome Tan, Pulp->Hair wtfTP
Total flow (mgd) 0.8
Beamhouse flow (mgd) ---------___-_ 0.575
Tanhouse flow (mgd) 0.225
Pollutant loadings - see Table 15.
Treatment plant operating day (hrs) 20
Equalized beamhouse flow (gpm) -------- ^79
Equalized tanhouse flow (gpm)- -------- 200
Total equalized treatment plant operating
flow (gpm) 679
Design and Cost Estimation of Components
Coarse Screening
This is not necessarily a part of a treatment system per se. Coarse
screening at the point the effluent stream emanates from the tannery is es-
sential whatever the destination may be, for protection of transmission lines
if nothing else. Therefore, this item is not being included as such, but
provision for removal of solids which can be separated by simple sedimenta-
tion is included in the plans for the alkaline and acid wastewater holding
tanks.
Raw Wastewater Pumps
These are needed only in the event that grades are not adequate for
gravity flow, and are related to transmission rather than treatment. In
most cases the holding tanks can be located below grade if necessary, and the
constant flow pumps will provide whatever elevation is needed.
Holding and Equalizing Tanks
The wastewater flow from the tannery arrives at the treatment plant in
two streams, beamhouse flow which is highly alkaline because of its lime and
sodium sulfide content, and tanhouse flow which is acidic. Both flows are
erratic because each is dependent upon batch operation dumps Also both
flows may contain suspended solids in sizes ranging from fiue ^ goss. In
view of difficulties encountered with entrained solids at existing treat-
lent Santa where their presence was not sufficiently recognized during the
desLf SaSe i?is considered essential to include solids removal in the
2 S£"s-h S^S teve tte ^
%£.•% sSotiS,, s* ^^^jrrsjs'ss
tion of each to direct sedimented soj-1^
entering end, very similar to a standard
99
-------
Beamhouse flow holding, equalizing, and clarifying tank
This tank is envisioned to be of concrete, rectangular,' and is di-
vided into two sections by a wall located two thirds of the total length
of the tank from the entering end. The wall extends from the top of the tank
to,/bhe bottom, with a three inch horizontal opening in the wall across the
full width of the tank, two feet from the bottom of the tank. This horizon-
tal slot opening allows flow to pass from-the first section into the second
section where the constant flow head box is located, whilst minimizing back-
passage of turbulence and discouraging wash-through of solids at times when
the liquid level may be low. The aforementioned scraper flights are located
in the first section, travelling in the direction counter to flow across the
bottom, thence vertically upward to near the top of the tank, horizontally
in the direction of flow across the top of the tank, and vertically downward
to the beginning. In order to avoid excessive length for the wooden flights
the width of the tank should not exceed twenty feet.
Design parameters
Detention time (hrs) -------------- 10
Beamhouse flow (mgd) -------------- 0.575
Width of tank - see above (ft) max 20
Sizing and specifications
Construction - concrete
Volume - 2$ x 5?5fOOO (gal) 239,000
Constant-gal/ft^ 7.5
Volume (ft-3) 32,000
Width (ft) 20
Length (ft) 100
Depth (ft) 16
Cost estimate
o
Estimated unit cost - see above (ft )- - - - $8.00
Volume (ft3) 32,000
Construction cost $256,000
Total cost including sedimentation
equipment (est) $275,000
Tanhouse flow holding, equalizing, and clarifying tank
This tank is also envisioned as being constructed of concrete, rec-
tangular, and of the same total concept as the beamhouse flow tank, except
that it is smaller, and the second section would not contain a constant flow
head box, but would be the location of the tanhouse wastewater flow pumps.
100
-------
Design parameters
Detention time (hrs) ^0
Tanhouse flow (mgd) 0 225
Width of tank (ft) - - max 20
Sizing and specifications
Construction - concrete
10
Volume - T5F x 225,000 (gal) 94,000
Constant - gal/ft3 y ^
Volume (ft3) 12,500
Width (ft) 20
Depth (ft) - 16
Length (ft) 40
Cost estimate
o
Estimated unit cost (ft ) $8.00
O
Volume (ft-*) 12,500
Construction cost --------------- $100,000
Total cost including sedimentation
equipment (est) $115,000
Constant Flow Equipment
The concept of constant flow through the treatment system was incor-
porated into the design of the Winchester, W.W.T.P. Pumps in the holding tank
elevate wastewater to an overflow weir box of special design (see Section 3),
from whence it flows to and through the system at a constant rate. This mode
of operation simplifies process control since all of the components of the
primary treatment section operate in unison without adjustment for flow
variations. The primary section operates either ail-on or ail-off, depend-
ing upon the availability of effluent to be treated, thus allowing constant
settings for dosing pumps and the dispersed air microbubble generator, and
eliminating wear and tear when flows are low or non-existent. The on-off
control is provided in this situation through level sensing switches located
in the beamhouse flow holding tank, which activate or interrupt the constant
head supply pumps and the tanhouse flow pumps according to the availability,
in this case, of alkaline tannery effluent.
101
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Constant flow head box
See Section 3
Design parameter
Horizontal cross section (gal/ft^/min) ------- 32
Sizing of vessel
Total volume of beamhouse flow (gpd) 575»000
Design treatment plant operating day (hr) ----- 20
Flow rate through weir box (gpm) ---------- 479
Gross sectional area needed @ 32 gal/ft2/min - (ft2) 15
Diameter (ft) . - - 4.5
Depth (ft) . 9
Cost estimate
Fiberglass lay-up $750
Constant flow supply pumps - beamhouse flow holding 'tank
These are submerged pumps to be located near the bottom of the beam-
house flow holding tank at the end opposite from the flow entrance. They
elevate the beamhouse wastewater to the constant-flow head box- and thence into
the treatment system. Two pumps, each capable of supplying full flow are in-
cluded here to avoid interruption in case of single pump failure.
Design parameter
Flow rate (gpm) 479
Sizing and pump specification
Capacity (gpm) 600
Manufacturer - Flyght Corp. Norwalk, Conn.
Model No. 6- GP - 3126
Motor HP 9.4
Cost estimate
Pumps - 2 $1,500 each $3,000
Tanhouse Wastewater Flow Pumps
Tanhouse waste will be collected in the tanhouse flow holding tank and
dispensed therefrom at a constant rate as long as alkaline waste is available
unless interrupted by the pH sensing device located in the main flow line
downstream of the constant flow head box, signalling that the danger condition
of pK 9.0 is being approached. It is estimated that the constant flow rate
for this material will be 200 gpm, which would deplete the design supply in
10.75 hours, slightly sooner than the design supply of alkaline beamhouse
waste from the beamhouse flow holding tank. Actual practice or pilot plant
102
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work might disclose that a higher rate of acid waste flow could be tolerated
but it seems important to have the two waste streams become exhausted at about
the same time. Two pumps, each capable of supplying full flow are specified
here, as in the beamhouse line, to avoid interruption in case of single pump
failure. * ^
Design parameter
Flow rate (gpm) 200
Sizing and specification
Capacity - each (gpm) . 200
Manufacturer - Flyght Corp.
Norwalk, Conn.
Model No - 4 - GP - 3105
Motor HP 5
RPM - - - - 1,750
Cost estimate
Pumps - 2 $1,000 each $2,000
pH Sensing for Acid Waste Flow Control
As noted in the foregoing this sensor would function only as a safe-
guard against development of an acid condition in the mixed wastewater flow.
Design parameters
pH range --------------------- 7«5 to 11
Power interruption level (pH) ---------
Specifications
Manufacturer - Beckman Instrument Go.
Cedar Grove, N. J.
Model No. - 940 pH analyzer
Special feature - !<%> dead band @ pH 8.0 to 9.0
Cost estimate
Instrument $1,500
Remote sensor connection - 150 ft. 200
Total - ^'7°°
Dosing Pump - Alum
Alum is used to develop agglomerated flocculation which not only aids in
entrapping and removing finely divided suspended solids, but also aids in en-
trapping microbubbles to enhance flotation. The alum is purchased and used in
wt. solids solution, sp. gr. 1.330.
103
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Design parameter
1,000 mg/Lto be added to combined beamhouse-tanhouse flow
Sizing and pump specification
2qualized beamhouse flow (gpm) ------------- 479
Equalized tanhouse flow (gpm) ------------- 200
Total equalized flow (gpm) 679
Weight of flow (ib/gal) 8.5
Weight of flow (ib/min) 5,770
Weight of alum @ 1,000 mg/l(lb/min) 5-77
Weight of stock alum solution needed @ k^% solids (ib) 12.82
Weight of stock alum solution (ib/gal) 11.1
Volume of stock alum solution needed (gpm) ----- 1.15
Pump capacity needed (gpm) ------------- + 1.15
Manufacturer - Liquiflo Equipment Go.
Warren, N. J.
Series 34 3 gpm | in. 316 S3
Motor HP (DC) 0.75
Speed - variable. Max rpm 1,725
Cost estimate
Pump and motor ------------------- $250
Dispersed Air Generator
See Figure 5«
Microbubbles are used to provide flotation for the suspended solids re-
moval principle used in this treatment system. Dispersed air is the least
expensive means for providing the same, see section 8.
Design paramter
Ft-' of air/100 gal of flow 0.5
Total equalized flow rate (gpm) --------- — 679
Sizing and specifications.
Manufacturer - Greey Corp.
Toronto, Canada
Model No. 6 - LEG - 300 316 S3
Motor HP 3
Cost estimate
Generator with motor, complete ---------- $4,500
104
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Coagulation Cell
See Figure 6 .
x ? US6d t0 provide Detention time to allow microbubbles and suspend-
ed floe to become intimately associated, thus enhancing flotation.
Design parameter
Effective residence time 2 minutes
Sizing and specifications.
Total equalized flow rate (gpm) ----------- 6?9
Cell volume required for 2 min. flow (gal) ----- 1,358
Cell volume required for 2 min. flow (ft^) ----- 181
Diameter of top section (ft) ------------ 7.5
Depth of top section (ft) -------------- 2.5
Width of bottom section (ft) ------------ 8.0
Length of bottom section (ft) ------------ 8.0
Depth of bottom section (ft) ----- -- _____ 2.0
Manufacturer - Local sheet metal fabricator
Cost estimate
Same as 19?6 updated <§ %?0 per year (est) ------ $10,500
Dosing Pump - Polyelectrolyte
This pump is used to continuously add about 12 ma/1 of polyelectrolyte
in 0,2?» solution to the waste stream to aid flocculation and flotation.
Design parameter
12 mg/1 to be added to combined flow.
Polyelectrolyte solution strength - 0.2^
Sizing and specifications.
Total equalized flow rate (gpm) ----------- 6?9
Weight of flow (ib/gal) --------------- 8-^
Weight of flow (Ib/min) ............... 5,700
Weight of polyelectrolyte needed @ 12 mg/1 (ib) --- 0.068
Solution strength (%} ----- • ----------- °-2
Weight of solution needed/min (ib) ---------- 3^
Factor - Ib/gal @ sp. gr. 1.015 ----------- 8«5
Volume of solution needed (gpm) - ---------- *
105
-------
Pump capacity needed (gpm) ------------- ^
Manufacturer - Liq.uiflo Equipment Go.
Series 36 5 gpm 3/4 in. 316SS
Motor (HP) - 0.75DC
Variable speed, i,?25 rpm max.
Cost estimate
Pump and motor (est) ---------------- $300
Bubble Classifier
See Figure ?
This unit is an open top, rectangular, steel tank through which the
waste stream is passed, after introduction of microbubbles, to allow oversize
bubbles to escape before entering the flotation basin. Large bubbles disrupt
the floating sludge blanket at the entering end of the LectroGlear tank.
Design parameter
» 2
Surface area (ft /100 gpm) 3
Depth (ft/100 gpm) 1
Sizing and specifications
Total equalized/flow rate (gpm) ---------- 679
O
Surface area - 100 x 3 (ft ) 20
Length (ft) 5
Width (f^g- 4
Depth -100x1 7
Manufacturer - Local sheet metal fabricator
Cost estimate
Tank complete (est) ---------------- $750
LectroGlear Solids Flotation Basin
See Figure 8
For description see Section 3
Design parameters
o
Surface area - ft /100 gpm —• 100
Vertical cross section perpendicular to direction
of flow - ft /100 gpm 15
Width - maximum (ft) --------------- 20
Electrode density - number/100 gpm -------- 20
106
-------
Sizing and specifications
Total equalized flow rate (gpm)
Area of vertical cross^section
® 15 ffyioo gpm (fir) --- - ........... 102
Depth of vessel, say (ft) ---------- . ___ 5
Width of vessel (ft) ----------------- j_7
Surface area @ 100 ft2/100 gpra (ft2) --------- 6?9
Length of vessel (ft) ----------_______ 40
Manufacturer - Local machinery fabricator
Cost estimate
Cost of Winchester LectroGlear (19?6) -------- $31,200
Update for 19?0 @ 8$ per year ------------ $35,000
Volume of Winchester unit (ft^) ----------- 2,100
o
Volume of unit sized as above (ft ) --------- 4,080
Comparative size (x) ---------------- 1.9^
Comparative cost of unit (19?8) -------- . --- $6?, 900
Electrodes needed ------------------ 136
Cost of electrodes, each -------------- $95
Total cost of electrodes -------------- $12,920
Total cost of flotation basin, installed (est) --- $80,820
Current Rectifier
Direct current is required for microbubble generation by electrolysis
in the LectroClear flotation basin.
Design parameter
2,600 amperes at 7 volts, D.C.
Sizing and specifications
Manufacturer - Oxymetal Industrial Corp., Warren, Mich.
Model - Udalite No. 4 MDV-5000
Type SASS e 460V
Water cooled
Cost estimate
Winchester cost (1976) including switches
and wiring, installed ............... $10,500
Estimated total cost updated to 1978 -------- $12,250
107
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Skimmings Pump
Floated solids in the LectroGlear unit are skimmed off and directed
into a receiving tank, see figure 8, from which they are pumped to sludge
holding tanks.
Design parameters
Open impeller trash pump design.
Capacity 2 times Winchester unit.
Sizing and specifications
Manufacturer - Gorman Rupp Go.
k inch intake, 3" discharge
Motor 3 HP, 1750 rpm, direct connected
Cost estimate
Pump, installed $1,500
Solids Slurry Pumps
Solids separated by sedimentation in the two holding tanks have to be
transferred to the sludge holding tank to be compacted along with skimmed
solids from the LectroClear and wasted solids from the carrousel. These will
be activated by timers. Three pumps are needed, one at each initial clari-
fier, beamhouse and tanhouse, and a third for a spare. The advantage of
standardization calls for specifying three alike.
Design parameters
Vaughn chopper pumps
Corrosion resistant construction
Sizing and specifications
Total volume of beamhouse flow (mgd) --------- 0.575
Suspended solids removed by sedimentation (mgA) (est)- 500
Constant (ib/gal) 8.5
Weight of beamhouse flow (ib/day) 4,887,500
Weight of suspended solids removed (ib/day) 2,445
Weight of solids slurry ® 1% solids (ib/day) 244,500
Constant (Ib/gal) 8.5
Average pumping rate $ 20 hr. day (gpm) ------- 24
Total volume of tanhouse flow (mgd) --------- 0.225
Suspended solids removed by sedimentation (est) (mg/L) 400
Weight of tanhouse flow (Ib/day) ---- - 1,912,500
108
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Weight of suspended solids removed (ib/day) ____ 760
Weight of solids slurry @ 1% solids (ib/day) ---- ?6,000
Weight of slurry (ib/gal) ------------- 8.5
Volume of tanhouse flow solids slurry (gpd) ____ 8,950
Average pumping rate @ 20 hr. day (gpm) ------ 7.5
Number of pumps required - 3 Interchangeable
Manufacturer - Vaughn Co., Inc.
Montesano, Wash.
Model 150. Motor 5 HP, 1,750 rpm
Cost estimate
Pumps, each $3,500 ----------------- $10,500
Sludge Storage Tanks
These tanks are used to accumulate and store sludge during the entire
wastewater flow period so that the filter press can be operated mostly during
the normal working day.
Design parameters
Storage capacity - 28 hrs.
Stirrers for uniformity and solids suspension
Sizing and specifications
Volume of flow in this W.W.T.P. (mgd) ------- 0.8
Volume of flow in Winchester W.W.T.P. (mgd) ---- 0.3
Factor for flow- increase (x) - - - - — ______ 2.7
Suspended solids analysis, combined wastewater,
this W.W.T.P. fogA) --------------- 2,718
Suspended solids analysis, raw wastewater, Winchester
(mg/l) ....................... i'295
Factor for suspended solids- increase (x) - _ - - -- 2.10
Volume of sludge generated at Winchester,
see table 9 (spd) ---------------- 18,000
Estimated sludge volume generated this W.W.T.P.
18,000 x 2.? x 2.1 (gpd) ............. 102,060
Estimated sludge volume - 28 hrs (gal) ------- 120,000
Number of tanks needed --------------- **
Construction - reinforced concrete, rectangular with stirrers.
109
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Size of tanks, each
Volume (gal) ---- ......... ---- 30,000
Volume (ft3) ------ - -------- -- 4,000
Depth (ft) --------- - -------- JA
Width (ft) ------------------ 18
Length (ft) ------------------ 18
Cost estimate
Estimated cost of rectangular concrete tank
construction (ft ) --------------- $8
Estimated cost of each tank ------------ $32,000
Estimated cost of four tanks ----------- $128,000
Estimated cost of four tanks with stirrers (est)~ - $150,000
Sludge Compaction
Compaction in this exercise calls for the use of a filter press, thus
requiring a special charging pump, and a heat exchanger to improve the rate
of filtration.
Sludge compaction pumps
Design parameters
Sand Piper, air actuated, or equivalent
Maximum delivery pressure (psi) --------- 100
Sizing and specifications
Total volume of sludge (gal/day) --------- 102,600
Sludge compaction operating day (hr) ------ 16
Sludge pump operating time (hrs) -------- 12
Average rate of sludge flow to filter press (gpm)
Peak rate of sludge flow to filter press
(start of batch) (gpm) 300
Pump capacity required (gpm) ---------- 300
Cost estimate
Manufacturer - Warren Rupp Pump Co.,
Mansfield, Ohio
Model no. - SA3A
Number required @ 300 gpm ------------ 2
Estimated cost, each -------------- $1,^00
Total cost -- --- -- ------ ------ $2,800
110
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Filter press
According to information available the plate and frame filter press is
capable of dewatering sludge to a greater degree than any other equipment de-
signed for that purpose. Maximum dewatering is economically essential.
Design parameters
Solids content of press cake (%} ------------ 35
Sizing and specifications
Total volume of sludge, Winchester (gpd) 18,000
Total volume of sludge, this unit (gpd) 102,600
Factor of size increase (x) -------------- 5.7
2
Total filter area, Winchester filter press (ft ) 2,^00
Filter area needed, this unit (ft2) - 13,680
Cost estimate
Cost of Winchester filter press, installed 19?6 $55,000
Cost of Winchester filter press, installed 19?8 - - - $6^,150
Estimated cost of unit 5*7 times larger $365,650
Heat exchanger
Design parameters
Stainless steel construction (316)
Temperature increase - 25°G to 65CG
Sizing and specifications
Contact area of Winchester unit (ft ) 88
Peak rate of sludge flow Winchester unit (gpm) 50
Peak rate of sludge flow this unit (gpm) 300
Factor of increase in contact area needed 6
\ j ,, /^
Estimated contact area, this unit (ft ) 528
Cost estimate
Cost of Winchester unit 19?6 $4,000
Cost of Winchester unit 19?8 $4'665
Cost of unit 6 times larger $28,000
111
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Air Compressor
Since the sludge compaction pump is air actuated it is important to
have an adequate and reliable air source readily available. It is possible
that the tannery compressed air would be adequate, but in the absence of in-
formation,, compressed air generation is being included.
Design parameters
Air pressure required (psi) ----------- max 100
Air volume required, each pump (cfm)~ ------ max 125
Sizing and specifications
Number of compaction pumps specified ------ 2
Air requirement vs. Winchester W.W.T.P. (x)- - - 2
Manufacturer - Kellog American
Oakmont, Pa.
Model no - A 462-TVI
Motor HP 25
Capacity @ 100 psi (cfm) 83
Cost estimate
Cost of Winchester compressor 19?6 $3,000
Cost of Winchester compressor 19?8 ------- 3.500
Cost of compressor with 2x capacity (est)~ - - - $5»000
Carrousel Oxidation Ditch
Design parameters
The volume of the oxidation ditch and the number and size of aerators
is determined by the amount of oxygen demanding material in the feedwater
entering the ditch, BOD and TKN each use oxygen. Both are substantially re-
duced in the primary treatment phase, BOD by 6Q&, and TKN by 40%. The re-
sidual material after primary treatment determines the load on the secondary.
Design MISS (mg/l) 7,500
Design F/M ratio - (BOD/MLSS) .06
Fixed design average swd in carrousel (ft)- - - - 13•A
Fixed design single channel width (ft) ----- 13
Oxygen required to satisfy BOD and TKN in the carrousel
1.5 x BOD + 4.6 x TKN
Oxygen rating per aerator 0?/hp/hr -------- 3.5
112
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Sizing and specifications
BOD present in combined flow raw wastewater (ng/1} 1,630
Residual BOD after 60?3 removal in primary (mg/l) 652
TKN present in combined flow raw wastewater (rag/I) 126
Residual TKN after 4C$ removal in primary (mg/L) 76
Average daily total flow (mgd) 0.8
BOD entering the secondary (ib/day) 4,353
TKN entering the secondary (ib/day) 507
Oxygen furnished per aerator (02/hp/hr) 3.5
Calculation of volume of carrousel
BOD i 0.06 = MISS (Ib)
l|353 f 0.06 = 72,550
72,550 Ib @ 7,500 mg/l » 1.15 M Sal
1.15 KG - 152,520 ft3
Calculation of surface area of carrousel
o
. Volume (ft-*) 152,520
Average depth (ft) 13.5
p
Surface area (ft ) 11,300
Calculation of total channel length
o
Surface area (ft ) ?• 11,300
Design channel width (ft) 13
Total channel length (ft) 870
Selection of number of channels
870 ft, total channel length required, indicates using a configura-
tion of three channel circuits, six single channels, each 135 ft.
long plus 80 ft of cross channel automatically included. This ar-
rangement" calls for three aerators.
Calculation of aerator horsepower required
Oxygen required - 1.5 x BOD + 4.6 x TKN
09 - 1.5 x 4353 •*• 4.6 x 507
£t
Q = 8,862 Ib/day
HP - 8,862 T (3.5 x 24) = 105.5
Three aerators will be used, see channel selection above.
Each aerator (HP) ko
113
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Cost estimate
Volume of Winchester carrousel (gal) ----------- 380,000
o
Volume of Winchester carrousel (ft )----------- $0,666
Volume of this carrousel (ft^) -------------- 152,500
Comparative size of this carrousel to Winchester
carrousel (x) --------------------- 3«0
Cost of Winchester carrousel unit 19?6 ---------- $197,700
Cost of Winchester carrousel unit 1978 (8/S/year) ----- $230,597
Estimated cost of this carrousel unit (3«^x) ------- $593,100
CarrouselTh license fee ($.10/gal) ----- - ------ $11^,985
Total cost, carrousel unit ---------------- $708,085
Secondary Glarifier
Although the primary section produces a clear effluent passing into
the secondary* biological activity in the secondary generates a high level
of suspended solids which have to be removed. They are relatively light in
density and therefore somewhat difficult to separate .
Design parameters
r\
Surface area at peak flow (gal/ft /day) ----- - -- - 300
Peak flow - 2x normal average flow.
Sizing and specifications
Total average wastewater flow (gpd) ------------ 800,000
Peak flow (gpd) --------------------- -1,600,000
Peak flow 4 300 (ft2) ------------------- 5,333
Diameter of 5,333 ft2 circle (ft) ------------- 82
Diameter of final clarlfier (ft) ------------- 82
Depth of final clarifier (swd) (ft) ------------ 8
Manufacturer: Glow Corp.
Florence, Ky.
Models Veof low . Periferal feed center sludge drawt. center
effluent outlet
Cost estimate
T
Volume of Winchester final clarifier (ft^) -------- 13 » 295
Volume of this final clarifier
Comparative size of this clarifier to Winchester
final clarifier (x) -- - --- ------- - ---- 3.2
114
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Cost of Winchester unit 1976 „ $33 500
Cost of Winchester unit 1978 $37,650
Estimated cost of this clarifier (3.2x) - - $120,000
Sludge Return Pumps
These pumps return solids separated in the final clarifier to the
oxidation ditch or to the sludge holding tanks as wasted.
Design parameter
Open pattern sludge pumps, standard construction, Midland Midwhirl
or equivalent 100$ return flow.
Sizing and specification
Total wastewater flow (gpd) . 800,000
Average wastewater flow (gpm) ~ - - _ 557
Manufacturer - Midland Pump Go.
Model Ho. - Midwhirl ^WS - 4-511
Capacity (gpm) 350
Motor HP 30
Cost estimate
Pump and motor - each ---------------- $2,500
Two required -------------------- $5,000
Chemical Tanks, Piping, Power and Wiring
The foregoing items and costs as calculated, and summarized in table
16, are, in part, for equipment in place, including excavation where required.
A major portion of the cost of construction of any treatment plant is for
small tanks, pumps and piping, power and wiring. Preliminary estimates for
these items, in the absence of engineering drawings, must be calculated from
existing data. Appendix B lists costs for many of the major items in the
Winchester treatment plant, total cost, and categorical costs for tanks,
pumps, piping and electrical. Taken as a group these total $122,500 out of
a total of $611,900, exclusive of housing and laboratory., or 20>S. This per-
cent of the total estimated cost of equipment for this exercise, as itemized
in table 16, amounts to $380,700. However, some items of pumps are included
in table 16, aggregating to $25,350, and thus must be deducted from the total.
So doing leaves an estimated balance amount, to cover chemical tanks, piping,
power and wiring, of $355,300
Housing
The dosing solution tanks, dosing pumps, flotation basin and sludge
compaction equipment must be protected from weather if located in other than
a tropical climate. Considering the size and possible arrangement of equip-
ment it is estimated that a building about 200 ft x 100 ft would be required.
115
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Specification
All steel, insulated, Butler building or equivalent
Forced ventilation at roof peaks.
Approximate size 100 ft x 200 ft.
Concrete slab floor with drains.
Cost estimate
Size of Winchester building -
Length (ft) 104
Width (ft) 40
Floor area (ft2) 4,160
Size of building needed, this exercise
Length (ft) . 200
Width (ft) - • • 100
Floor area (ft2) 20,000
Cost of Winchester building 19?6 $8?,500
Cost of Winchester building 19?8 (est) - - - $102,000
Estimated cost of housing, this project ------ $400,000
This estimate has been reduced from $500,000 in deference
to size, realizing that there would be some economy in scale.
116
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TABLE 16. SUMMARY OP TREATMENT PLANT COMPONENTS
AND ESTIMATED COST FOR CATEGORY 1 CHROME TAN-PULP HAIR
GATTLBHIDJJ: TANNERY
Item
Cost
Beamhouse flow holding, equalizing, and clarifying tank
Tanhouse flow holding^ equalizing, and clarifying tank
Constant flow head box
Constant flow supply pumps
Tanhouse wastewater flow pumps
pH sensing for acid waste flow,control
Dosing pump - alum ^
Dispersed air generator
Coagulation cell
Dosing pump - polyelectrolyte
Bubble classifier
LectroClear solids flotation basin
Current rectifier
Skimmings pump
Solids slurry pumps
Sludge storage tanks
Sludge compaction pump
Air compressor
Filter press
Heat exchanger
Carrousel oxidation ditch, complete
Secondary clarifier
Sludge return pumps
Total for above
Chemical tanks, piping, power and wiring
Housing
Total
Contingencies - lQ?i
Total estimated cost of project
$275,000
115,000
750
3,000
2,000
1,700
250
ij-,500
10,500
300
750
80,820
12,250
1,500
10,500
150,000
2,800
5,000
365,650
28,000
708,085
120,000
5.000
$1,903,355
355,300
il-00,000
$2,658,700
265,800
$2,92^,500
117
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Estimated Cost of Operation
Examination and study of table 15 reveals that a cattlehide, chrome,
pulp hair, tannery could be expected to emit effluent in slightly less volume
per pound of raw hide or pelt than a shearling tannery, 6.1 gal/lb hide vs.
7.2. In terms of BOD and suspended solids, the cattlehide tannery wastewater
contains about double the amount of the shearling tannery in each instance.
Since most of the cost of operation is in removal and deposition of suspended
solids, and in electric power for aeration to support biological activity for
BOD reduction, it follows that the cost of operation of a treatment facility
for a cattlehide, chrome, pulp-hair tannery would be about double that of a
shearling tannery. Section 8 reveals a cost of $1.7?Per thousand gallons of
wastewater treated. Assuming some economy of scale the cost of operation for
this model would be expected to be on the order of $3.00 per one thousand
gallons treated.
118
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PRELIMINARY DESIGN AND COST DEVELOPMENT
FOR A WASTEtfATER TREATMENT PLANT
FOR A VEGETABLE TAN-SAVE HAIR CATEGORY 3
GATTLEHIDE TANNERY
Comparison of parameters in Table 15 for the category 3 tannery - veg
tan, cattlehide, hair save - with category ?, shearlings, reveals a high de-
gree of similarity. BOD, Suspended Solids, and volume of effluent, the most
significant parameters, are all very close to being the same. In category 3,
as in category 1, alkaline beamhouse wastes and acid tanhouse wastes are in-
volved. Therefore the same approach to treatment, particularly as it per-
tains to the primary section, would be used as for the category 1 tannery.
See schematic diagram, Figure 43. Also the same sources for background in-
formation are used in this exercise as used for the category 1 development
preceding.
Basic Design Parameters - Vegetable Tan, Save Hair tf.tf.T.P.
Total flow (mgd) 0.3
Beamhouse flow (mgd) ------------------- 0.215
Tanhouse flow (mgd) 0.085
Polluta-nt loadings - see Table 15
Treatment plant operating day (hr) ----------- 20
Equalized beamhouse flow (gpm) ---------- 179
Equalized tanhouse flow (gpm) 71
Total equalized treatment plant operating flow (gpm) 250
Design and Cost Estimation of Components
Coarse Screening
Not included. See comments page 99..
Raw Wastewater Pumps
Not included. See comments page 9°.
Holding and Equalizing Tanks
See general comments page 99,. The sizing of the two tanks in this
case are calculated on the basis of volume needed to accomodate 10 hours of
flow from each source, alkaline and acid.
119
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CONSTANT
HEAD BOX
DISPERSED AIR
COAGULATION
ALKALINE FLOW
.EQUALIZATION TANK
ALUM
BEAMHOUSE FLOW
CLARIFIER
CELL BUBBLE
CLASSIFIER
SLUDGE
HOLDING
TANKS
Figure lj.3.
Schematic Diagram of Proposed Wastewater Treatment Plant for
a Category 3 Vegetable Tan Save Hair Cattlehide Tannery.
-------
Beamhouse flow holding, equalizing, and clarifying tank
This tank is of concrete rectangular. See general comments page 100.
Design parameters
Detention time (hr) ^0
Beamhouse flow (mgd) 0.215
Sizing of tankn
Volume - 24" x 215,000 (gal) - 89,600
Constant - gal/ft _ 7,5
Volume (ft3) 11,944
Width (ft) - 14
Length (ft) 65
Depth (ft) 13
Cost estimate
rt
Estimated cost - see page (ft ) --------- $8
Volume (ft3) 11,944
Construction cost -------------- — 95»552
Total cost including sludge moving equipment (est) $110,000
Tanhouse flow holding, equalizing, and clarifying tank
This tank is also constructed of concrete, rectangular, and of the
same total concept as the beamhouse flow tank except that it is smaller. See
comments page 100 .
Design parameters
Tanhouse flow (mgd) 0.085
Detention time (hr) 10
Sizing of tank
Volume - 24 x 85,000 ( gal) 35»^20
Constant - gal/ft3 ?-5
Volume - (ft3) ^'?22
Width (ft) ^
Depth (ft) - 13
Length (ft) 26
121
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Cost estimate
Histirnated cost - _____----- $8
Volume (ft3) 4,722
Construction cost ------------------ $37»77&
Total cost including sludge moving equipment ----- $50,000
Constant Flow Equipment
See general comments page 101-.
Constant flow head box
See section 3
Design parameter
r~)
Horizontal cross-section (ft /gal/ruin) -------- 32
Sizing of vessel
Total, volume of beamhouse flow (gpd) 215,000
Design treatment plant operating day (hr) ------ 20
Flow rate through weir box (gpm) ----------- 179
Cross sectional?area needed
@ 32 gal/ft /inin (fir) -- 5.6
Diameter (ft) 3
Depth (ft) 6
Cost estimate
Fiberglass lay-up, standard mandrel --------- $500
Constant flow supply pumps
See general comments page 102 .
Design parameter
Flow rate (gpm) - - 179
Sizing and pump specification
Capacity (gpm) ------------------- 300
Manufacturer - Flyght Corp.
hodel No. 6-CP-3126
Capacity - 600 gpm 9.4 HP
Cost estimate
Pumps - 2 $1,500 each $3,000
122
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Tanhouse vJastewater Flow Pumps
See general comments page 102 .
Design parameter
Flow rate (gpm) ----
Sizing and pump specification
Capacity, each (gpm) ---
Manufacturer - Flyght Corp.
Model No. if-CP-3105
Motor HP-------~-----~~~_______ 5
Cost estimate
Pumps - 2 $1,000 each --------------- $2,000
pH Sensing For Acid Waste Flow Control
See general comments page 103 .
Design parameters
pH range --------------------- -7-5 to 11
Power Interruption level (pH) ------------ 9»0
Specifications
Manufacturer - Beckman Instrument Go.
Cedar Grove, N. J.
Model No. - 940 pH analyzer
Special feature - ICP/o dead band SpH ------- 8.0 to 9.0
Cost estimate
Instrument --------------------- $1,500
Remote sensor connection (150 ft) --------- 200
Total ........................ $1.
Dosing Pump - Alum
See general comments page 103.
Design parameter
l,000mg/lto be added to combined beamhouse-tanhouse flow
Alum solution 45^ solids @ sp gr 1.330, 11.1 Ib/gal.
123
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Sizing and pump specification
Equalized beamhouse flow (gpm) ---------- 179
Equalized tanhouse flow (gpm) --------- — 71
Total equalized flow (gpm) ------------ 250
Weight of flow (Ib/gal) 8.5
I/eight of flow (Ib/mln) 2,125
Weight of alum @ l,000mg/l (ib/rain) 2.12
Weight of alum solution & k$}o solids (ib/min) 4-7
Volume of alum solution @ 11.1 Ib/gal (gpm) - - - 0,42
Pump capacity required (gpm) ---------- +0.5
Manufacturer - Liquiflo Equipment Go.
Series 34 3 gpm 0,5 in 316 S3
Motor HP 0.75 DC
Variable speed - max rpm ------------- 1»725
Cost estimate
Pump and motor (est) $250
Dispersed Air Generator
See Figure 5
See general comments page 104.
Design parameter
Ft-3 of air/100 gal of flow 0.5
Sizing and specifications
Manufacturer - Lighting Mixer Corp.
Model No. - 4 - LSC - 200 5 in 316 S3
Motor HP . 2
Cost estimate
Generator with motor, complete ---------- $3i500
Coagulation Cell
See Figure 6
See general comments page 105.
Design parameter
Effective residence time 2 minutes
124
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Sizing and specifications
Total equalized flow rate (gpm) 250
Cell volume required for 2 min flow (gal) 500
Cell volume required for 2 min flow (ft-*) 6?
Diameter of top section (ft) 7,5
Depth of top section (ft) 2.5
Diameter of bottom section (ft) 7.5
Depth of bottom section (ft) 1.8
Manufacturer - Local sheet metal shop
Cost estimate
Same as Winchester 1976 updated to 1978 $10,500
Dosing Pump - Polyelectrolyte
See general comments page 105.
Design parameter
12 mg/1 to be added to combined flow
Polyelectrolyte solution strength - 0.270
Sizing and specifications
Total equalized flovr rate (gpm) ---------- 250
Weight of flow (ib/gal) 8.4
Weight of flow (ib/min) 2,100
Weight of polyelectrolyte needed © 12 mg/1 (ib) .024
Solution strength (%} 0.2
Weight of solution needed @ 12ag/l (lb) 12
Weight of solution (ib/gal) 8-5
Volume of solution needed (gpm) 1«^
Pump capacity needed (gpm) 1«^
Manufacturer - Liquiflo Equipment Go.
Series 36-5 gpm 0-75 in 316 S3
Motor HP 0.75DC
Variable speed 1,725 rpm max
Cost estimate
Pump and motor (est) $300
125
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Lubble Classifier
See Figure ?
See general comments page 106.
Design parameter
Surface area = 3 ft /100 gprn flow
Depth - 1 ft/100 gpm
Sizing and specifications
Total equalized flow rate (gpm) ----------- 250
Surface area @ 3 ft2/100 gpra (ft2) 7.5
Depth (ft) 2.5
Manufacturer - Local sheet metal shop
Cost estimate
Same as 19?6 updated @ 6%/yr (est) ----. i<500
-------
Cost estimate
Winchester cost (19?6), including switches and
wiring, installed $10 ^00
Estimated total cost updated to 1978 $12 2C0
Skimmings Pump
See general comments page 108.
Sizing and specifications
Same as Winchester
Cost estimate
Pump, installed • $1,500
Solids Slurry Pumps
See general comments page 108.
Design parameters
Vaughn chopper pumps
Corrosion resistant construction
Sizing and specification
Total volume of beamhouse flow" (rngd) --------- . 0.215
Suspended solids removal by sedimentation (est) (mg/L)- 500
Constant (ib/gal) 3.5
Weight of beamhouse flow (ib/day) 1,827,500
Weight of suspended solids removed (ib/day) ----- 91^
Weight of solids slurry @ 1% solids (ib/day) 91>/-!-00
Weight of slurry (ib/gal) -------------- 8.5
Volume of beamhouse flow (gpd) 10,750
Average pumping rate & 20 hr. day (gpm) 9
Total volume of tanhouse flow (mgd) 0.085
Suspended solids removed by sedimentation (est) (jngA) ^0°
Constant (Ib/gal) 8-5
Weight of tanhouse flow (Ib/day) 722,500
Weight of suspended solids removed (Ib/day) 289
Weight of solids slurry S \% solids (Ib/day) 28,900
Weight of slurry (Ib/gal) 8-5
Volume of tanhouse flow solids slurry (gpd) 3,iK)0
127
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Average pumping rate '•& 20 hr. day (gpm) ------ 3
Number of pumps required - 3 Interchangeable
Pump selection - Vaughn Chopper
Manufacturer - Vaughn Go., Inc.
Hontesano, Wash.
Model 150 Motor 5 HP 1,750 rpm
Cost estimate
Pumps, each $3,500 - - - $10,500
Sludge Storage Tanks
These tanks are used to accumulate and store sludge during the entire
daily wastewater flow period so that the filter press can be operated mostly
during the normal working day. Table 15 indicates that the total hydraulic
flow, and the incidence of suspended solids is no more in the veg-tan hair
save cattlehide tannery than at Winchester, therefore, the same tank design
and capacity can be used. See section 3«
Cost estimate
Two 12,000 gallon steel tanks
$3,500 each $7,000
Sludge Compaction
See general comments page 110.
Since the wastewater in this exercise is expected to generate the same
amount of sludge as the Winchester tannery effluent, the same equipment items
and the same size of each can be used.
Sludge compaction pump
Specification
Manufacturer - Warren Rupp Pump Co.
Mansfield, Ohio
Model No. - SA3A
Cost estimate
. Number needed --- — _______________ j_
Estimated cost installed --_---------__
-------
The press now in service at Winchester should be adequate for this
use. u
Specifications
Manufacturer - D. R. Sperry Go.
East Aurora, 111.
Model No. 48 EHG_.
75 rectangular, pyramid face pattern, 48 in by 48 in plates.
Center feed, corner vent.
Cost estimate
Cost of Winchester press 1976 $55,000
Cost of Winchester press 1978 $64,150
Heat exchanger
The unit now used for this purpose at Winchester should be adequate.
See section 3«
Specifications
Manufacturer Eimco, Inc.
Length (ft) 14
Diameter (in) ----- — ____________ 8
Two pass.
Cost estimate
Cost of Winchester heat exchanger 1976 $4,000
Cost of same 1978 $4,665
Air Compressor
See general comments page 112.
The same size compressor as that in use at Winchester will suffice.
Design parameters
Air pressure required (psi) max 100
Air volume required (cfm) roax 125
Sizing and specifications
Number of compaction pumps 1
Air requirement vs. Winchester same
129
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Manufacturer - Kellog American
Oakinont, Pa.
I-;odei Ko. A-462-TVI
I-iOtor HP 25
Capacity 3 100 psi (efm) 8.3
Cost estimate
Cost of Winchester compressor 19?6 --------- $3,000
Cost of Winchester compressor 19?8 --------- $3,500
Carrousel Oxidation Ditch
Due to similarity of wastewater characteristics a ditch of the same
size and detailed specifications should be adequate for this use. See sec-
tion 3«
Cost estimate
Cost of Winchester unit 19?6, exclusive of pumps, piping, '
valves, and electrical - $251,200 /
Cost of same, 1978' $293,000
Secondary Clarifier
See general comments page 114.
As is true with other components of this treatment plant the Win-
chester size arid specifications will provide an adequate secondary clarifier.
See section 3«
Cost estimate
Cost of Winchester secondary clarifier 19?6 - - $33,500
Cost of Winchester secondary clarifier 19?8 - $39,000
Sludge Return Pump
See general comments page 115•
Same size as used at Winchester.
Specification
Manufacturer - Midland Pump Co.
Model No. - Midwhirl 4W3-4511
Capacity (gpm) 350
Motor Hi' 30
Cost estimate
Pump and motor --------------____ $2,500
130
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Housing
See general comments page il6.
The same steel Butler building will provide the protection needed for
this application. See section 3«
Specification
Manufacturer - Butler Buildings, Inc.
Dimensions - 40 ft wide x 104 ft long.
Concrete floor with drains.
Cost estimate
Cost of Winchester Butler building 1976 - $8?,500
Cost of Winchester Butler building 1978 -------- $102,000
Chemical Tanks, Piping, Power and Wiring
See explanation page 115. Refer to table 17 instead of table 16 for
itemization of equipment and. totalisation of cost.
Cost estimate
Total cost of itemized equipment, this exercise - - - - $667,745
20?o of total cost »- 133i549
Itemized cost of pumps, table 17- • 24,050
Estimated cost of chemical tanks, piping, power
and wiring --- - - 109,500
131
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TABLE 1?. SUMMARY OF TREATMENT PLANT
COMPONENTS AND ESTIMATED COST
FOR CATEGORY 3 VEGETABLE TAN
SAVE: HAIR CATTLEHIDE TANNERY
Item
Cost
Beainhouse flow holding, equalizing, and clarifying tank- - - - $110,000
Tanhouse flow holding, equalizing, and clarifying tank - - - - 50,000
Constant flow head, box -------------------- 500
Constant flow supply pumps ------------------ 3»000
Tanhouse wastewater flow pumps ---------------- 2,000
pH sensing for acid waste flow control ------------ 1,700
Dosing pump - alum ---------------------- 250
Dispersed air generator ------------------- 3»500
Coagulation cell ----------------------- 10,500
Dosing pump - polyelectrolyte ---------------- 300
Bubble classifier 500
LectroClear solids flotation basin -------------- 43,430
Current rectifier ---------------------- 12,250
Skimmings pump ------------------------ 1,500
S'olids slurry pumps --------------------- 10,500
Sludge storage tanks --------------------- 7,000
Sludge compaction pump -------------------- 4,000
Filter press ------------------------- 64,150
Heat exchanger ------- — - ----___--_____ 4,665
Air compressor ------------------------ 3,500
Carrousel oxidation ditch ---------_-________ 293,000
Secondary clarifier -----------------_____ 39,000
Sludge return pump --------------------- 2,3.00
Total for above $667,745
Chemical tanks, pumps, power and wiring -------____ 109,500
Housing 102,000
Total 879,245
Contingencies - 10% 87,925
Total estimated cost of project ---------______ $967,170
132
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Estimated Cost of Operation
Reference to table 15 reveals that there are no substantial differ-
ences in pollution load or volume, per pound of raw hide or pelt, between a
cattlehide, veg tan, hair save, category 3 tannery and a category ? shearling
tannery. Therefore the operating costs presented in terms of a number of
parameters in section 8 are applicable to this model.
General Statement
It must be recognized that the attempted technology transfer from a
category 7 tannery to one of category 1 and one of category 3, as described
in some detail in this section is not based upon actual experience. Obviously
there has been no opportunity to apply the principles used in the Winchester
'•treatment system on any other tannery wastewater. The concept suggested for
receiving and combining two waste streams, alkaline and acid, only seems to
have credibility based upon observations at the South Paris facility. As for
biological activity in the oxidation ditch with respect to carbonaceous as
well as nitrogenous bacteria strains it can only be speculated that similar
results would be forthcoming if similar conditions would be established.
The factor of scale has not been taken into account in the calcula-
tions for construction of most of the high cost items, particularly in the
chrome cattlehide model, hence more engineering refinement could reveal
lower costs there.
133
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SECTION 10
REUSE OF TREATED WASTEWATER
A definite potential would seem to exist for wastewater reuse at the
Winchester tannery. River water, the primary source of plant process water,
has substantial deficiencies. During the winter, the water temperature is
well below the acceptable level for use, and during the summer, it can be too
warm. At times of flooding contamination is considerable, and, indeed at all
times it is far from pure. Thus the treated effluent water is consistently
more uniform in some important aspects than the source from which it is drawn,
and seemingly it could be used to advantage at almost any point in the process.
Recycled water does have some real limitations, however. The purpose
of wash water is' to carry off contaminants and other unwanted components, and
some of these, particularly sodium chloride (salt),are non-compatible pollu-
tants. These pass through the treatment plant and are present to almost the
same degree after treatment as before. Consequently, in order to avoid com-
pounding the existence of these materials in the process water, consideration
of recirculation has to be performed in the light of this restraint.
Positive action should be taken to recover some of the energy used to
heat process water. Wastewater taken after passing through the primary sec-
tion of the treatment plant could be expected to be 40°F warmer in winter and
10°F warmer in summer than river water, a year-round average of 25°F. This
represents heat that would normally be wasted but that perhaps could be re-
covered simply by recycling. On the other hand contaminants in the form of
BOD, ammonia, TKN, and traces of residual dyestuffs still exist in this water.
During the secondary treatment step the continuous churning of me-
chanical aeration lowers the water temperature through evaporative cooling,
and during the cold season direct heat transfer to the atmosphere occurs.
Accordingly it might seem more reasonable to consider reusing water which has
passed through the primary section only when concerned with heat recovery.
However, the unique design of the carrousel with respect to resistance to at-
mospheric interference accomplishes heat retention to a large degree even in
winter, so that the temperature differential between effluent water from the
secondary clarifier, and river water becomes 30°F in winter and 5°F in summer,
or an average of 1?.5°F. While this is not as attractive as the primary ef-
fluent average differential of 25°F it is certainly appreciable and tips the
scales in favor of using totally treated effluent in the reuse concept versus
the somewhat warmer but less pure primary treated effluent flow.
The primary individual uses for water in a shearling tannery include
initial pelt washing, soaking, make-up water for saturated brine, hose-down
134
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for clean-up, make-up water for pickle liquors and certain tan liquors, and
wash and make-up water used during dyeing and fat-liquoring procedures. Note
that all of these uses, with the exception of hose-down for clean-up, have the
capacity for adversely affecting the quality of the product. Therefore any
potential dangers not identified by rationalization must be determined through
extensive trial before reuse is instituted. Each usage as above will be con-
sidered individually as to material and energy savings. Obviously the material
savings will be limited to salt since the water to be used is the product of a
purification process designed to remove other components which conceivably
otherwise might be present in recoverable amounts.
RECOVERY AND USE FOR PELT WASHING
A large portion of the water used in this tannery is used for washing
pelts. As received they contain much salt and animal soil. The water used is
river water warmed as necessary, depending upon the time of year, to about
85°F, thus consuming energy. No salt is used at this point. In fact, a large
part of this exercise is salt removal. Thus it becomes necessary to consider
the impact of adding salt to the wastewater discharge system at this point
from two directions rather than one if wastewater is reused, that in and on
the skins, as usual, and that in the recycled wastewater if recycling should
be practiced. The following facts help to examine this situation:
Pelts processed per day ------------- 3,600
Salt in and on pelts as received (lb/pelt)- - - - 1.5
Salt entering the system on pelts (ib/day) 5,^00
Water used for pelt washing (gal/day) 150,000
Weight of water @ sp. gr. 1.000 (ib/gal) 8.3^5
Specific gravity of effluent 1.005
Weight of effluent @ sp. gr. 1.005 (ib/gal) 8.38?
Weight of 150,000 gal of recycled effluent (ib) 1,258,050
Salt content of effluent (%) I-2
Salt entering the system in recycled
effluent (ib/day) -- 15,097
These figures clearly show that on the order of three times as much
salt would return to the pelt washing operation as it is desired to remove,
thus interfering greatly with the efficiency of this process step. Even if
effective washing couM be achieved by using effluent for the first batch
washes, and fresh water for the last batch washes, recycling of even half as
much salt would lead rapidly to saturation of the wastewater system with sodium
chloride.
135
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Energy Saving
As stated above, initial pelt washing does consume a considerable
amount of energy in the use of wash water at 100°F. However, as discussed in
the foregoing paragraph, the concept of recycling water containing salt to a
process step that is primarily concerned with salt removal, prevents serious
consideration of any other aspect of reuse, including energy saving.
RECOVERY AND USE FOR BRINE PREPARATION
Recycling of effluent for use in brine preparation could result in
measurable savings. The lixator system for brine preparation, as practiced
at Winchester, in itself is a purification process since make-up water is
passed through a large bed of rock salt as a means to achieve saturation.
This mode of reuse of treated wastewater seems to hold the greatest promise
of success among those envisioned.
Material Saving
The following facts apply:
Salt used in brine preparation (ib/day) ------ 30,000
Salt content of saturated brine (lb/gal)- ----- 2.65
Volume of brine used (gal/day) 11,400
Since 11,400 gal of saturated brine is consumed each day, on the aver-
age, this is the limit of recycle volume for effluent to be used for this
purpose.
Weight of effluent @ sp. gr. 1.005 (lb/gal) . 8.38?
Weight of 11,400 gal effluent (ib) 95,608
Salt content of effluent (%) 1.2
Salt content of 11,400 gal effluent (ib) 1,14?
Cost of rock salt as received (ib) - ------- $.018
Value of salt recovered / day ---------- -$20.65
Value of salt recovered / year (250 days) $5,160
Energy Saving
Volume of wastewater possibly recycled for brine
preparation (gal/day) 11,400
See calculation for energy saving page 138 - - - -
Yearly saving, heat recovery in brine preparation - $990
136
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RECOVERY AND REUSE FOR HOSEDOWNS AND CLEAN-UP
No material or energy savings are envisioned for this reuse per se.
Temperature or salt content are not important. Pumping costs would be no less
than for fresh water. On the other hand, considering the wastewater volume as
an entity, it is cooled, particularly in winter, through the addition of cold
river water to it as a result of using such water for hose-downs and clean-up.
Therefore, reuse of wastewater for this purpose could result in indirect
energy conservation.
Energy Saving
Calculations are made as followsi
Volume of water used for hose-down and
clean-up (gal/day) 15,000
See calculation for energy saving page 138 - - -
Yearly saving, this use $1,300
RECOVERY AND REUSE FOR PICKLE LIQUOR MAKE-UP
Material and energy savings are possible in this category. Reused ef-
fluent would carry salt and heat energy into the pickle liquors which would
not have to be provided otherwise. Effluent contains l.Zfc salt, and is 1?.5°F
warmer, on the average, than fresh water. As stated before, untried quality
considerations are paramount, and this use could only occur after extensive
trial and experience.
Material Savings
The volume of water needed for pickle liquor make-up determines the
degree of economy in effluent recovery for this purpose. The salt would
automatically reduce the amount of saturated brine needed to reach the pro-
cess specification, for salometer. The following facts apply:
Volume of new pickle liquor (gal/day) 12,000
Salt content of effluent (%} 1.2
Weight of effluent (ib/gal) 8.38?
Salt content of 12,000 gal effluent (ib) 1,208
Cost of rock salt as received (ib) — $-018
Value of salt recovered / day $21.7^
Value of salt recovered / year $5,^35
137
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Energy Saving
Volume of wastewater recycled for pickle liquor,
make-up (gal/day) 12,000
See calculation for energy saving below.
Yearly saving, this use -------------- $1,042
RECOVERY AND REUSE FOR TAN LIQUOR MAKE-UP
This reuse is much the same as for pickle liquor make-up. A common
distribution system would serve both uses. Again, the salt would automatic-
ally reduce the amount of saturated brine needed to reach the required total
salometer level.
Material Savings
Volume of new tan liquor (gal/day) -------- 20,000
Salt content of effluent (%} 1.2
Weight of effluent (ib/gal) 8.38?
Salt content of 20,000 gal effluent (ib) 2,013
Cost of rock salt as received (ib) $.018
Value of salt recovered / day $36.23
Value of salt recovered / year ---------- $9,058
Energy Saving
Volume of wastewater recycled for chrome
liquor make-up (gal/day) ---------- 20,000
See calculation for energy saving below.
Yearly saving, this use $1,738
RECOVERY AND REUSE - TOTALIZED ENERGY SAVINGS
Potential volume for saturated brine preparation
(gal/day) 11,400
Potential volume for hose-down and clean-up 15,000
Potential volume for pickle liquor clean-up
(gal/day) 12,000
Potential volume for tan liquor make-up (gal/day) 20,000
Total potential volume effluent reuse (gal/day) - 58,400
Weight of effluent (ib/gal) 8.38?
138
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Weight of recycled volume (ib/day) 489,800
Average temperature in excess of river water (°P) - i?«5
BTU recoverable /day S,5?l,51^
Fuel value of fuel oil (BTU/gal) 1^,000
Equivalent gallons of oil recoverable / day 58
Cost of oil/gal $0.35
Value of recovered heat / day $20.30
Value of recovered heat / year $5*075
139
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TABLE 18. RECAP OF SAVINGS POSSIBLE THROUGH RECOVERY AND REUSE
Material Energy
Use $ / year $/year
Brine preparation 5,160 990
Hose-down and clean-up - 1,300
Pickle liquor make-up 5,^35 1,042
Tan liquor make-up 9,058 1,738
Total 19,653 5,070
Grand Total $24,723
The combined saving is substantial. It is probably not factual to ex-
pect that all of the heat energy would be recovered, but since this represents
by far the lesser portion of the total savings, the heat loss during transmis-
sion would not seriously impact the total.
In order to determine the viability of a proposed recycle system from
the point of view of cost of operation and cost of construction versus savings
to be realized, it is first necessary to make a preliminary design of an ef-
fluent return system.
Figure W is a schematic drawing of the tannery, the treatment plant,
and a proposed effluent return system, more or less to scale.
ESTIMATED COSTS FOR EFFLUENT REUSE
Consideration of Operating Costs
Figure *& schematically shows fresh river water entering the tannery
for process use. The water is used almost entirely on the first, or ground
floor, and is distributed in part to the same areas and use points as con-
sidered for reuse of treated wastewater. This water is pumped from the level
of the river to the point of use through a vertical rise of about twenty feet.
Purified effluent water would be pumped from a point about ten feet above the
level of the river to exactly the same level of use. Thus the static head
against which each of the pumps would be working is virtually the same in each
case. The only other difference between the two would be several hundred feet
of additional pumping distance for the returned effluent, incurring some addi-
tional dynamic head due to pipe friction. Again this is insignificant, assum-
ing proper design and pipe sizing. It is also the case that the two differences
are counterbalancing.
140
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I 100 f T. 1
LIXATOR
TREATED EFFLUENT ftETUftN LINE
-------
The conclusion becomes, therefore, that pumping costs will be the same
whether fresh water or treated wastewater is used where applicable.
Consideration of Construction Costs
Figure 44 shows that a return system for treated effluent would consist
of a pump withdrawing treated water from the outfall from the final clarifier,
and discharging into an underground (below frost level) return line to the
tannery buildings, and thence to the points of use. All piping and valves
would be PVG. The main would be of fairly large size all the way, with re-
duction fittings and smaller size pipe, valves, fittings, etc. at each point
of use. Following are design parameters and cost estimates:
Pumps
Estimated volume to be reused (gal/day) ---------- 58>400
Time frame for reuse - minimum (min/day) --------- 480
Average volume to be reused (gal/min) ----------- 122
Estimated peak volume (gal/min) -------------- 150
Pump specifications
Capacity (gal/min) ----------------- 150
5" suction, 4" discharge standard centrifugal,
iron body, motor direct connected (HP) ------- 30
Estimated cost of pump and motor, inplace --------- $3,000
Power supply, wiring and switches (est) ---------- 1,000
Labor (est) ------------------------ 500
Total for pump $4,500
Weather protection (pump house)
Construction - Prefabricated insulated aluminum
Concrete floor-
Size - 8 ft by 8 ft or standard.
Estimated cost inplace ------------------ $750
Pipe main to tannery building
Pump suction line
50 ft. 5 in PVC - $315/C ft. - $158
Foot valve and fittings ----------------- 75
142
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Underground to tannery.
750 ft It in PVG - $235/C ft |lf?62
Trench and backfill 1500
Pipe fittings (est) ----- 2QO
Labor (est) -- —. , ^Q
Total . . $4,445
Piping inside tannery buildings
Distribution main
700 ft 4 in PVG - $245/C ft $1,715
Pipe fittings (est) 500
Labor (est) . 1,500
Total - - _ . $3,715
Valving assemblies at each pair of paddle pits.
One 4 in to 2 in reducing tee --------------- $10.40
One 2 in to 1 in reducing tee --------------- 7.60
Two 1 in valves PVG - $13.00 each 26.00
Two 1 in 45° tees - $1.46 each 2.92
Four ft 2 in pipe - $90.75/0 ft 3.63
Two ft 1 in pipe - $42.00/G ft .84
Total material for each pit piping assembly 51.44
Labor for each pit piping assembly (est) 25.00
Total cost of each pit piping assembly 76.44
Average number of pits in use
Pickle Pits J°
Tan Pits °2
Total Pits to be equipped - 102
Number of assemblies needed 51
Total cost of use assemblies $3.900
143
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TABLE 19. RECAP OF ESTIMATED EFFLUENT REUSE CONSTRUCTION COSTS
Item
Pump
Pump house
Outside Main
Inside Main
Point of use assemblies
Material
$4,500
600
3,695
2,215
2.625
$13,635
Labor
$500
150
750
1,500
1,275
$4,175
Total $17,810
It is not realistic to estimate any project cost on labor and material
alone. Overhead is always involved. It is customary to add on the order of
of the direct labor cost for this item, or, in this case, $6,262.00.
Grand total estimated cost of distribution system for reclaimed ef-
fluent wastewater.
Material and equipment -------------- $13,635
Labor -------------- -_-___-- i
Overhead -------------------- 6.262
Total ................ $24,072
This estimated total of $24,072 for cost of equipment in place compares
very favorably with the estimated annual saving of $24,734, especially in view
of anticipated equality in operating costs. It must be emphasized again, how-
ever, that some of the reuses envisioned could seriously impair quality and a
careful program of evaluation of each potential use would most certainly have
to be undertaken before adoption.
USE OF FILTER PRESS CAKE AS FUEL
The 35^ solids filter press cake that results from compaction of
solids removed from the waste stream is ordinarily land-filled. This material
has a fuel value, on a dry basis, of about 6,000 BTU/lb, compared to coal at
13,000 BTU/lb. The relatively low fuel value and high moisture content
(65^) make the filter cake uninteresting as a fuel. A further consideration
is the presence of trivalent chromium which poses the threat of formation of
hexavalent chromium by oxidation during combustion. Production of such a
highly toxic compound would make any burning of the filter cake a hazardous
undertaking.
It is the conclusion, therefore, that the filter press cake is not a
viable source of energy.
144
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REFERENCES
1. Ramirez, E. R. and Clemens, 0. A., "Recovering Marketable Values from
Beef Packinghouse Wastewaters," WWSMA Pollution Conference, Houston,
March 1976.
2. Ramirez, E. R., "Electrocoagulation Clarifies Food Wastewater," Ohio
Water Pollution Control Conference, 48th Annual Meeting, Toledo, June
3. Ramirez, E. R., "Electrocoagulation Clarifies Food Wastewater," Deeds &
Data, WPCF, April 1975.
4. Ramirez, E. R. and Clemens, 0. A., "Electrocoagulation Techniques for
Primary Treatment of Several Different Industrial Types of Wastewater,"
49th Conference of WPCF, Minneapolis, October 1976.
5. Ramirez, E. R., Barber, L. K., and Clemens, 0, A., "Primary Physiochemi-
cal Treatment of Tannery Wastewater Using Electrocoagulation," 32nd
Industrial Waste Conference, Purdue University, West Lafayette, May 1977•
6. Ramirez, E. R., and Barber, L. K., "Clarification of Tannery Wastewater
by Electroflotation," Tannery Pollution Control Seminar, New England
Tanners Club, November 1977-
;\
7. Stensel, H. D., and Wright, J. D., "Cost Effective and Energy Efficient
Wastewater Treatment," 33rd Industrial Wastewater Conference, May 1978.
8. Passveer, I. A., "Simplified Method of Sewage Purification," Report
No. 26, Research Institute for Public Health Engineering, T.N.O.,
Netherlands.
9. Zemaitis, W. L., and Jenkins, C. R., "Biological Activity in the Oxida-
tion Ditch Method of Waste Water Treatment," American Institute of Chemi-
cal Engineers, 1971•
10. Stensel, H. D., Refling, D. R., and Scott, H. S., "Carrousel Activated
Sludge for Biological Nitrogen Removal," Book, "Biological Nutrient Re-
moval." Ann Arbor Science, October 1978.
11. Sawyer, C. H., Wild, H. E. Jr., and McMahon, T. C., "Nitrification and
Denitrification Facilities," E.P.A. Technology Transfer Seminar Publica-
tion, August 1973-
145
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12. Ford, D. L., and Elton, R. L, "Removal of Oil and Grease from Industrial
t/astewaters," Chemical Engineering Deskbook Issue, October 197?•
13. Leather Tanning and Finishing Development Document, Draft, Revised,
U.S.E.P.A. October 19?8.
146
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BIBLIOGRAPHY
1. "Aeration in Wastewater Treatment", Water Pollution Control Federation.
Washington: 1971. ~~~"~"~ ~"~—
2. "BASF Applies the Big Treatment", Chemical Week. April 2, 1975.
3. Burchinal, J. C., Jenkins, C. R., "Ditches Provide Efficient Treatment",
Environmental Science and Technology. 3:11:11?0; 1969.
4. Horskotte, G. A., Niles, D. G., Parker, D. S., Caldwell, D. H., and
Horstokotee, D. G., "Full-Scale Testing of a Water Reclamation System",
Journal of Water Pollution Control Federation. 1*6 p. 181; 1974.
5. Jacobs, A., "Loop Aeration Tank Design Offers Practical Advantages",
Water and Sewage Works, October and Novembers 1975.
6. Koot, A. C. J., and Zeper, J., "CARROUSEL, A New Type of Aeration-System
With Low Organic Load, Water Research, Pergamon Press Vol. 6; 1972.
7. Maier, P., "A Dutch Approach Toward Sewage Treatment and Automation of
Sewage-Treatment Plants", Progress in Water Technology, Vol. 6; 1974.
8. Matsche, N. F., and Spatzierer, G., "Austrian Plant Knocks Out Nitrogen",
Water and Wastes Engineering, January; 1975•
9- Metcalf and Eddy, Inc., "Wastewater Engineering", McGraw-Hill; 1972.
10. Monn, E. P., "Design and Maintenance of Extended Aeration Sewage Treat-
ment Plants", Public Works, January; 19&9-
11. Murphy, R. S. and Ranganathan, K. R., "Bio-Processes of the Oxidation
Ditch When Subjected to a Sub-Arctic Climate", Report No. IWR-27,
Institute of Water Resources, University of Alaska, May; 1972.
12. "Operation and Maintenance of Wastewater Treatment Facilities", United
States Environmental Protection Agency. Washington, August; 1974.
13. Parker, H. W., "Oxidation Ditch Sewage Treatment Process", Volume 6,
Water Supply and Waste Disposal Series, U. S. Department of Transporta-
tion, April; 1972.
14. Pasveer, I. A., "Simplified Method of Sewage Purification", Report No.
26, Research Institute for Public Health Engineering. T. N. 0., Nether-
lands.
147
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15. Pas veer, I. A., "A Case of Filamentous Activated Sludge", Journal
of Water Pollution Control Federation, 51, p. 1340; 1969.
16. Procedure Manual for Evaluating the Performance of Wastewater Treatment
Plants, Environmental Protection Agency;
17. Sweeris, S. and Trietsch, R., "Determination of the Oxygenation Capacity
in CARROUSEL Plants", H20, February and March; 197^.
18. Zemaitis, W. L., and Jenkins, C. R., "Biological Activity in the Oxida-
tion-Ditch Method of Waste Water Treatment", American Institute of
Chemical Engineers; 1971.
19. Zeper, J. and DeMan, A., "New Developments in the Design of Activated
Sludge Tanks With Low B.O.D. Loadings", I.A.W.P.R.. San Francisco,
July; 1970.
148
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APPENDIX A
LETTERS FROM J. L. WITHEROW TO J. A. REID CONCERNING ANALYSIS OF
STANDARD SAMPLES FOR ANALYTICAL QUALITY CONTROL
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
Industrial Environmental Research Laboratory - Cincinnati
, Food and Wood Products Branch
i
w^ Corvallis Field Station
^ &
-------
s
\
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
.to I/,,,
' Industrial Environmental Research Laboratory — Cincinnati
Food and Wood Products Branch
Corvallis Field Station
200 S.W. 35th Street
Corvallis, Oregon 97330
July 13, 1977
Mr. John A. Reid
A. C. Lawrence Leather Co., Inc.
1 Bridge Street
Winchester, NH 03470
Dear John:
Your analytic results for NH3-NS N03-N, PO--P, KjN, and T-P
arrived July 11, 1977. The standard values of the lower concentrations
were 2.6, 1.2, 0.13, 2.1 and 0.85 mg/1, respectively. The standard
values for the higher concentrations were 8.8, 6.7, 2.4, 38. and
4.28 mg/1, respectively. Seven of your results were "on the money."
As you can see the PO,-P were half the standard values and the
lower KjN value was srightly more than 2 times the standard value.
This suggests that'dilution of the samples for these analyses may
have been in error.
Since we have been concerned over NH3-N measurement techniques
I checked and found one standard deviation for concentrations 3 and
4 was 0.4 mg/1 and 1.3 mg/1, respectively. This standard deviation
was developed from an analyses by a number of laboratories in a
"round robin" testing program. This is about a 15% variation from
the mean. Your data indicates accuracy and no difference between
the two methods of analyses.
Standard deviations for concentration 3 and 4 on PO,-P were
0.04 and 0.4 mg/1, respectively. The standard deviation for con-
centration 5 for K.N is 0.5 mg/1. Because of the large standard
deviation in the P64-P analyses we would not reject your two
values. The K.N value of 5.04 mg/1 would be rejected.
J
Thank you for running these standards. If you find dilution
was the problem I would appreciate knowing. Toward the middle of
the project or upon your request I will forward two additional
'sets of standard samples to aid in your quality control efforts.
Very truly yours,
Jack L. Witherow
Food Products Staff
cc: Mr. Barber
150
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APPENDIX B
INITIAL COST OF WINCHESTER TANNERY WASTEWATER TREATMENT PLANT
PRIMARY CLARIFICATION SYSTEM
Holding tank $62,100
Dispersed-air unit 3,500
Coagulation cell 9,300
Flotation basin 31,200
Electrodes 17.300
Rectifier and wiring ------------- 10,500
t
Chemical tanks, pumps and piping ------- 50,700
Power and control wiring ----------- 3^,200
Laboratory 8,900
Housing for above -------------- 87,500
Total $315,200
SLUDGE DENATURING
Air-powered press pump ----------- $3,500
Filter press and related sludge removal
equipment ---------------- 68,700
Switches and wiring, installation ------ 5,000
Total - $77,200
SECONDARY BIOLOGICAL
Carrousel license -------------- £J6,300
Concrete work 119,4-00
Aerators 51,800
Pumps, piping, valves, etc. - 19,700
Electrical 12,900
Monitoring and control equipment 15,200
Excavation and miscellaneous -------- 26,500
Total $283,800
SECONDARY CLARIFIER $33,500
TOTAL FOR SYSTEM $709,700
151
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO,
EPA-600/2-79-110
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Processing Chrome Tannery Effluent To Meet Best
Available Treatment Standards
5. REPORT DATE
July 1979 (issuing date)
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Lawrence K. Barber, Ernest R. Ramirez*, William L. Zemaitis**
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
A. C. Lawrence Leather Co., Inc.
Winchester, N.H. 031*70
10. PROGRAM ELEMENT NO.
1BB610
11. CONTRACT/GRANT NO.
S 804504
12. SPONSORING AGENCY NAME AND ADDRESS
Industrial Environmental Research Lab. - Cinti., OH
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, OH
13. TYPE OF REPORT AND PERIOD COVERED
Final Report
14. SPONSORING AGENCY CODE
EPA/600/12
15. SUPPLEMENTARY NOTES
*Swift Environmental Systems, Chicago, Illinois 60680
**Envirobic Systems, New York, New York 10001
16. ABSTRACT
To satisfy stream discharge requirements at its Winchester, N.H.,
chrome tan shearling tannery, the A. C. Lawrence Leather Co. , Inc.
selected primary and secondary systems that are unique as applied to
tannery effluent treatment in the United States. Primary clarification
is accomplished by means of coagulation and flotation, using electrolytic
as well as mechanical micro-bubble generation. The secondary biological
section is a so-called CARROUSEL,™ a technical modification of the
Passveer oxidation ditch. During the 12-month study, complete analytical
data representing winter as well as summer operating conditions were
acquired along with operating cost data.
This report presents these data and describes the design and operation
of the system. Possible applications of the same principles to other
tannery wastewaters are also suggested.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
;. COSATI l-'ield/Gtoup
Leather
Processing
Wastewater
Activated Sludge Process
Economic Analysis
Waste characterization
68 D
18. DISTRIBUTION STATEMENT
19. SECURITY CLASS (This Report/
Unclassified
21. NO. OF PAGES
RELEASE TO PUBLIC
20. SECURITY CLASS (This page)
Uncl assi'
.162.
22. PRICE
EPA Form 2220-1 (Rev. 4-77)
152
U. S. GOVERNMENT PRINTING OFFICE: 1979 — 657-060/5349
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