United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
EPA-600/D-82-331 October 1982
£,EPA QECHNOLOGY
T
RANSFER
The Bridge Between
Research and Use
Design Manual for Dewatering Municipal
Wastewater Sludges
The newly published Technology Transfer Design Manual for
Dewatering Municipal Wastewater Sludges was distributed at
the 55th Annual Conference and Exhibition of the Water Pollution
Control Federation (WPCF) in St. Louis, Missouri, October 3-8,
1982.
The selection and design of dewatering equipment for organic
sludges produced during primary and secondary municipal waste-
water treatment involves consideration of many factors. The
procedure is complicated by interaction among the dewatering
process, prior treatment processes, and subsequent treatment,
transportation, and ultimate disposal requirements. This manual
outlines a five-step approach to the selection and design of
dewatering equipment for either new or the upgrading of existing
treatment facilities: (1) initial screening; (2) initial cost evaluation;
(3) laboratory testing; (4) field level testing; and (5) final evaluation
based on detailed design parameters. Generally, all five stages
would be considered for dewatering facilities at a large plant,
while only stages 1 to 3 would be considered for small plants.
Also included in the manual is a discussion of sludge character-
istics which would affect dewatering,' brief descriptions of
dewatering processes, and a discussion of the capabilities of
these dewatering processes. Conditioning chemicals and typical
dosages used in sludge dewatering were also discussed.
Direct energy requirements for the dewatering operation, as
well as indirect energy requirements for conditioning chemicals,
are presented for each dewatering process. To illustrate the
relative costs of different treatment, transport and disposal
systems, comparative cost estimates are presented for 1, 5, and
50 ton/day capacity sludge treatment systems. A summary of
nine recent side-by-side comparisions of different dewatering
techniques is also presented to illustrate recent trends in the
selection of dewatering equipment. An appendix containing
capital and operation and maintenance cost curves for eight
dewatering processes is also included.
The order number for this publication is 1014.
Handbook: Identification and Correction of
Typical Design Deficiencies at Municipal
Wastewater Treatment Facilities
ThisTechnologyTransfer handbook has been prepared for use
by engineers involved in the design and/or review of designs for
Publicly Owned Treatment Works (POTWs). Its intent is to identify
design deficiencies found to limit POTW performance. Design
considerations have been developed that will eliminate these
deficiencies during the design phases of the project. The docu-
ment will prove useful to personnel involved in the operation and
maintenance of POTWs since procedures are presented, where
feasible, for correction of design deficiencies at existing facilities.
Use of the handbook will assure that the design incorporates a
maximum number of operational conveniences.
Typical design deficiencies found in POTWs are identified and
associated methods to correct each of the deficiencies noted are
presented. The information is not intended for use as a trouble-
shooting guide for process-oriented operating problems.
The handbook describes design deficiencies that contribute to
performance and reliability problems, poor safety practices,
and/or decreased flexibility of plant process control. The result of
such deficiencies may be any combination of increased plant
operations and maintenance, cost, and energy requirements. The
handbook is intended to provide design engineers with guidance
that will make their designs more operable and maintainable at
less cost, as well as more flexible in providing adequate perform-
ance during times of changing influent characteristics.
The order number for this publication is 6007.
Handbook: Remedial Action at Waste
Disposal Sites
This Technology Transfer handbook explains the nature of
contamination at waste disposal sites and describes some of the
remedial actions that can be applied for the clean-up of each
contaminated medium. Remedial actions are designed to control,
contain, treat or remove contaminants from uncontrolled hazard-
ous waste sites, and are divided into surface controls, ground-
water controls, leachate controls, direct treatment methods, gas
migration controls, techniques for contaminated water and
sewer lines, and methods for contaminated sediment removal.
The handbook is intended for use by industrial and governmental
technical personnel involved with the clean-up of uncontrolled
hazardous waste sites. When used in conjunction with the
proposed National Contingency Plan, it will assist in the develop-
ment of technically sound, environmentally protective, consistent,
cost-effective remedies.
The handbook presents information on technologies that may
be applicable to specific problems of controlling hazardous
wastes at disposal sites. It does not cover any technology
exhaustively, nor is the subject of alternative disposal methods
addressed except in the context of remedial measures at
uncontrolled sites. Neither are the topics of quick- or short-term
remedial response actions or management/manifesting pro-
cedures considered to be appropriate for inclusion in this
handbook.
The order number for this publication is 6006.
Thermal Conversion of Sludge—Conference
The "International Conference on Thermal Conversion of
Municipal Sludge" sponsored by the USEPA's Office of Research
and Development will be held March 22, 23 and 24,1983 at the
Sheraton Hartford Hotel, Trumbull Street & Civic Center Plaza,
Hartford, Connecticut. The purpose of the conference is to
disseminate the latest information on the design and operation of
thermal sludge conversion systems with primary emphasis on
incineration. For further information write to. Dr. Atal E. Erlap,
USEPA-MERL, 26 West St Clair Street, Cincinnati, OH 45268;
telephone 513/684-7663; or Dr James E. Smith, Jr., at the same
address; telephone 513/684-7394.

-------
Innovative Technology: The Sequencing
Batch Reactor
There are a number of recently developed technologies which
offer potential cost and energy savings and other benefits. One of
these is the Sequencing Batch Reactor (SBR).
A full-scale 0.3 mgd SBR demonstration project funded by the
USEPA was initiated April 1979 in Culver, Indiana. The major
conclusion from the Culver study is that the SBR is capable of
treating domestic wastewater for removal of BODs and SS,
nitrification, and denitrification. Phosphorus removal can be
accomplished using chemicals. Specifically, it was found that
effluent limits of 10 mg/l BODs and SS could easily be achieved in
an SBR. Effluent ammonia nitrogen concentrations of less than
1.0 mg/l were also easily achieved. Nitrification and denitri-
fication occurred simultaneously during fill and react modes.
Finally, the SBR at Culver was easy to operate and, as the
treatment plant operator indicated, "more forgiving than the
continuous-flow system."
A SBR system may include one or more tanks, each having five
basic modes of operation: fill, react, settle, draw, idle. Fill is the
receiving of the raw wastewater; react describes the period of
treatment; settle is clarification; draw is effluent discharge; and
idle is the waiting period until the next cycle begins. Time clock
controls can be used, as well as level sensors or turbidity sensors,
to operate the system. Microprocessors are also easily adapted to
control SBR operations. In fact, the present stage of development
of a batch process in Australia is a fully automated system
requiring only unskilled operators. Variations in flow, loads and
treatment requirements govern the method of controls used.
Solids wasting is done after the settle period or during react and
can be accomplished from twice-per-monthfor a simple one-tank
system to once-per-cycle for a more complex multi-tank system.-
Neither primary nor separate secondary clarifiers are required,
and no recycle pump is necessary, indicating potential for
significant savings in construction as well as O&M costs.
This innovative process is presently under construction in
Grundy Center, Iowa and under design in Sabula, Iowa.
The design of Grundy Center consists of two SBR tanks to treat
0.83 mgd. The two basins are common-wall constructed each
sized 48'x28' (15' SWD) with a volume of 47,300 ft3 (1340 m3)
and surface area of 3,150 ft2 (290 m2). Each basin is a racetrack-
type endless channel. Operation will be controlled by the use of a
microprocessor. The innovative SBR was one of six prequalifica-
tion bidding proposals for the secondary treatment portion of the
facility. The other five were conventional continuous-flow stirred
tank reactors including clarifiers and return sludge pumping.
The SBR system cost $687,000 and saved 18.2% in construc-
tion costs compared to the least-cost conventional alternative
which cost $841,500. The SBR system will use 285,500 kwh/yr
(10,160 M J/yr), saving 9.4% in power requirements compared to
the conventional alternative. With the elimination of clarifiers
and return activated sludge pumping and use of microprocessor
control for automatic operation, significant O&M cot savings will
be made. In addition, operation of this system will be simple and
reliable.
Three Additional Flue Gas Desulfurization
Summary Reports Available
Three additional summary reports on sulfur oxides control from
fossil fuel burning steam and electric generating facilities have
been prepared. In addition to existing reports on the Wellman-
Lord and dual alkali processes, reports on the magnesium oxide,
lime/limestone, and spray dryer processes are now available.
The magnesium oxide (MgO) flue gas desulfurization (FGD)
process is a sulfur dioxide (SO2) recovery system that uses a
recirculating MgO slurry to remove S02from stack gas. The slurry
reacts with SO2 to form magnesium sulfite (MgS03>, which is
then heated to regenerate MgO. The concentrated SO2 release
during regeneration can be converted to sulfuricacid(H2S04)and
other products.
Major advantages of the MgO FGD process include the ability
to
•	Recover sulfite salts easily from the slurry
•	Regenerate the absorbent (MgO)
•	Alleviate the problem of solids disposal
Wet time/limestone FGD processes employ a scrubbing slurry
of lime or limestone to remove SO2. As a side benefit, these
processes also remove fly ash and chlorides. Lime and limestone
FGD processes are similar. Both are nonregenerable. Their
operation is based on the ability of an aqueous slurry of slaked
lime, Ca(0H)2, or wet ground limestone, CaCOs, to absorb SO2
from flue gas. Absorbed SO2 is removed from solution by a
chemical reaction that forms a calcium sulfite and calcium sulfate
solid solution and insoluble calcium sulfate dihydrate. These salts
precipitate in a holding tank. A continuous bleed stream removes
part of the slurry from the holding tank to be concentrated and, as
an optional step, stabilized. It is common practice to dispose of the
resulting solid in ponds or as landfill.
Lime/limestone systems are usually less complex than regen-
erate systems, and they cost less to install and operate that other
FGD processes. Consequently, lime/limestone FGD processes
are the most widely used FGD systems in operation.
Spray dryer FGD is a throwaway process in which S02 is
removed from the flue gas by an atomized lime slurry, Ca(OH)2, or
a solution of sodium carbonate, Na2COs- The hot flue gas dries the
droplets to form a dry waste product while the absorbent reacts
with SO2 in the flue gases. Dry waste solids—consisting of sulfite
(S03) and sulfate (S04) salts, unreacted absorbent, and fly ash-
are collected in a fabric filter (baghouse) or electrostatic precipita-
tor (ESP) and are typically disposed of by landfill.
Interest in spray dryer FGD has been spurred primarily by the
potential cost savings dry FGD offers over conventional wet FGD,
particularly for low-sulfur coal (less than 1.5 percent) applica-
tions.
For those interested in obtaining the reports, the EPA order
numbers are as follows:
•	Magnesium oxide 	 8005
•	Lime/limestone 	 8006
•	Spray dryer 	 8009
Capsule Report Describes on Adipic
Acid Additive Test Results
This is the fifth in a.series of capsule reports describing the
results of the Shawnee Lime and Limestone Wet Scrubbing Test
Program conducted by EPA's Industrial Environmental Research
Laboratory, Research Triangle Park, North Carolina.
This report describes the results of adipic acid-enhanced lime-
and limestone testing at the Shawnee Test Facility from July
1978 through March 1981. Also reported are preliminary results
from the 100 MW full-scale demonstration being conducted at
the Southwest Power Plant of Springfield City Utilities, Spring-
field, Missouri and from the 27 MW equivalent industrial boiler
test at Rickenbacker Air Force Base.
A primary objective of the EPA alkali wet scrubbing tesli
program during the last several years has been to enhance SO?
removal and improve the reliability and economics of lime and
limestone wet scrubbing systems by use of adipic acid as a
chemical additive.
The order number for this publication is 2029.

-------
REQUEST FOR TECHNOLOGY TRANSFER MATERIAL
PROCESS DESIGN MANUALS
Phosphorus Removal (April 1976) 			1001 ~
Sulfide Control in Sanitary Sewerage Systems (Oct. 1974)		1005 ~
Nitrogen Control (Oct. 1975)		1007 ~
Wastewater Treatment Facilities for Sewered Small
Communities (Oct 1977)		1009 ~
Municipal Sludge Landfills (Oct. 1978)		1010 ~
Sludge Treatment and Disposal (Oct 1979)		1011 ~
Onsite Wastewater Treatment and Disposal Systems (Oct 1980)		1012 ~
Land Treatment of Municipal Wastewater (Oct. 1981)		1013 ~
Dewatering Municipal Wastewater Sludges (Oct. 1982)		1014 ~
TECHNICAL CAPSULE REPORTS
Third Progress Report: Lime/Limestone Wet-Scrubbing Test
Results at the EPA Alkali Scrubbing Test Facility	2010 ~
First Progress Report Wellman-Lord SO2 Recovery Process—Flue
Gas Oesulfurization Plant	 2011 ~
Fabric Filter Particulate Control on Coal-Fired Utility Boilers-
Nucla, CO and Sunbury, PA	 2013 ~
Double Alkali Flue Gas Oesulfurization System Applied at the
General Motors Parma. OH Facility	 2016 ~
Recovery of Spent Sulfuric Acid from Steel Pickling Operations	 2017 ~
Fourth Progress Report' Forced-Oxidation Test Results at the EPA
Alkali Scrubbing Test Facility	 2018 ~
Control of Acidic Air Pollutants by Coated Baghouses	 2020 ~
Particulate Control by Fabric Filtration on Coal-Fired
Industrial Boilers	 2021 ~
Bahco Flue Gas Oesulfurization and Particulate Removal System	 2022 ~
First Progress Report Physical Coal Cleaning Demonstration at
Homer City. PA	 2023 ~
Acoustic Monitoring to Determine the Integrity of Hazardous
Waste Dams			 2024 ~
Restoration of Medical Lake (Washington)	 2025 ~
Restoration of Lake Temescal (California)	 2026 ~
Lake Restoration in Cobbossee Watershed (Maine)	 2027 ~
Disposal of Flue Gas Desulfurization Wastes' Shawnee
Field Evaluation	 2028 ~
Adipic Acid-Enhanced Lime/Limestone Test Results at the
EPA Alkali Scrubbing Facility	 2029 ~
INDUSTRIAL SEMINAR PUBLICATIONS
Erosion and Sediment Control—Surface Mining in the
Eastern U.S. (2 Vol )	 3006 ~
Pollution Control in the Forest Products Industry 	 3010 ~
MUNICIPAL SEMINAR PUBLICATIONS
Upgrading Lagoons	 4001 ~
Benefit Analysis for Combined Sewer Overflow Control	4013 ~
~ U.S. GOVERNMENT PRINTING OFFICE: 1982	559-017/0793
BROCHURES
Environmental Pollution Control Alternatives* Municipal
Wastewater	5012 ~
Environmental Pollution Control Alternatives: Economics of Wastewater
Treatment Alternatives for the Electroplating Industry	5016 ~
Environmental Pollution Control Alternatives Centralized Waste
Treatment Alternatives for the Electroplating Industry	5017 ~
HANDBOOKS
Industrial Guide for Air Pollution Control (June 1978)		6004 ~
Continuous Air Pollution Source Monitoring Systems (June 1979) ....	6005 ~
Remedial Action at Waste Disposal Sites (June 1982)		6006 ~
Identification/Correction of Typical Design Deficiencies at
Municipal Wastewater Treatment Facilities (Oct 1982}		6007 ~
INDUSTRIAL ENVIRONMENTAL
POLLUTION CONTROL MANUALS
Pulp and Paper Industry—Part 1/Air (Oct 1976) 	. 7001 ~
SUMMARY REPORTS
Control and Treatment Technology for the Metal Finishing
Industry Series1 Sulfide Precipitation	 8003 ~
Sulfur Oxides Control Technology Series FGD Dual
Alkali Process	 8004 ~
Sulfur Oxides Control Technology Series FGD Magnesium
Oxide Process	 8005 ~
Sulfur Oxides Control Technology Series. FGD Lime/Limestone
Processes	 8006 ~
Control and Treatment Technology for the Metal Finishing
industry Series. Ion Exchange	 8007 ~
Control and Treatment Technology for the Metal Finishing
Industry Series* In-Plant Changes 	 8008 ~
Sulfur Oxides Control Technology Series FGD Spray
Dryer Process	 8009 ~
EXECUTIVE BRIEFINGS
Short-Term Tests for Carcinogens, Mutagens, and Other
Genotoxic Agents	 9003 ~
Diesel Emissions Research Report		 . . , 		 9004 ~
Environmental Assessment. Perspective on the Emerging
Oil Shale Industry	 9005 ~
ENVIRONMENTAL REGULATIONS AND
TECHNOLOGY PUBLICATIONS
Environmental Regulations and Technology
The Electroplating Industry	10001 ~
ATTENTION PUBLICATION USERS
Due to the increasing costs of printing and mailing, it has become necessary to institute positive management controls over distribution of Technology Transfer
publications Although these publications will be distributed on a no-cost basis, any request for more than five documents total, or for more than one copy of a single
document must be accompanied by written justification, preferabaly on organization letterhead. In the event your order cannot be filled as requested, you will be
contacted and so advised
If you are not currently on the mailing list for the Technology Transfer Newsletter, do you want to be added? Yes ~	No ~
Name 	,					
Street	
City/State/Zip Code	—	—		
Note- Forward to CERI, Technology Transfer, U.S. Environmental Protection Agency, Cincinnati, OH 45268

-------
Emerging Technology Assessments
One function of ORD's Municipal Environmental Research
Laboratory, Cincinnati, Ohio, is to provide technical support to
state and regional management of the Agency's Innovative and
Alternative Technology Program. In particular, one program
objective is to increase awareness of new developments in
wastewater treatment technologies among consulting engineers,
municipal officials, and state and local water pollution control
agencies. As a direct output, a series of Emerging Technology
Assessment reports has been developed to provide a state-of-
the-art review of new developments in municipal wastewater
treatment technology and a thorough, objective engineering
evaluation that compares performance, costs, and energy
consumption with equivalent conventional systems. Of 20
Assessments that have been initiated, five have been published:
Deep Shaft Biological Reactor (EPA-600/2-82-002); Fine Bubble
Aerators (EPA-600/2-82-003); Anaerobic Treatment (EPA-600/
2-82-004); Vertical Well Chemical Reactor (EPA-600/2-82-005);
and Solar Thermal Energy in Wastewater Treatment (EPA-
600/2-82-006).
Assessment reports for wetlands, aquaculture, the biological
aerated filter, and the sequencing batch reactor are in final draft
form (a brief summary of the sequencing batch reactor follows
this article). During the next 18 months, additional Assessments
will be completed on; anaerobic digestion of combined wastes;
Carver/Greenfield sludge dewatering; sludge combustion tech-
niques; trickling filter/solids contact process; sludge disinfection
techniques; biological phosphorus removal; small diameter
gravity sewers; large soil absorption systems; aerobic thermo-
philic sludge digestion using air; in-channel clarification in an
oxidation ditch; and aeration/mixing techniques.
To further disseminate information on new municipal waste-
water treatment technologies, a series of Emerging Technology
Seminars is planned for 1983. Selected technologies, with
appropriate case studies, will be presented and discussed in
detail.
Environmental Aspects of the Oil Shale
Industry
Oil shale deposits in the United States are among the richest
and most extensive in the world. Total identified resources of
medium and rich shales in the Nation are estimated at 2 trillion
equivalent barrels (320 billion equivalent cubic meters) of oil. The
Green River formation alone—which covers an area of 17,000
square miles (44,000 square kilometers) in Colorado, Utah, and
Wyoming—contains an estimated 1.8 trillion equivalent barrels
(280 billion equivalent cubic meters) of oil. About 600 billion
barrels (95 billion cubic meters) is considered recoverable by
currently known technology.
This environmental assessment;
• Summarizes available information on oil shale sources
In-Plant Changes Provide Alternatives
for the Metal Finishing Industry
The metal finishing industry in the United States is subject to a
variety of changing business conditions. Two of the most
significant factors are the increasing costs of materials, such as
plating chemicals and process water, and the environmental
considerations, which include the need to control the discharge
of effluent waste streams and the disposal of hazardous wastes.
The survival of many metal finishing companies will depend on
how effectively they deal with the impact of these changes and
requirements.
•	Summarizes major air, water, solid waste, health and other
environmental impacts
•	Analyzes applicable pollution control technology
•	Provides guidance for sampling, analyzing, and monitoring
emissions, effluents, and solid wastes from oil shale pro-
cesses
This assessment provides a brief summary of a more compre-
hensive report. Environmental Perspective on the Emerging Oil
Shale Industry (EPA-600/2-80-205). The full report provides a
preliminary overview of environmental considerations related to
the emerging oil shale industry. The report and similar ensuing
reports are intended to develop the technical basis for eventual
regulations.
The order number for this publication is 9005.
Because of rising prices and changing regulations, it is
necessary to re-evaluate water pollution control techniques and
costs and to examine methods for improving raw material yields.
In many cases, changing the manufacturing process can signifi-
cantly alter chemical losses and water flow rates. These in-plant
changes usually involve techniques for reducing both the drag-
out removed from process solutions and the amount of water
used in the rinsing process. The overall effect is a reduction of:
•	Chemical purchases
•	Water use (resulting in lower water and sewer costs)
•	Wastewater treatment needs and disposal costs
The order number for this publication is 8008.
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Postage and
Fees Paid
Environmental
Protection
Agency
EPA 335
Official Business
Penalty for Private Use $300
RETURN POSTAGE GUARANTEED

-------