United States
Environmental Protection
Agency
Office of Water
WH-552
Washington, DC 20460
April 1986

EPA 440/1-86/093
Water
Multimedia Technical
Support Document for the
Ethanol - for - Fuel Industry

-------
-*    .     r'»    "-    :   i-i  "-V  '  *  :• £  =••« = •-•---  t_* ^Wty^&jfX-r'^fft^™^"^''^??!^^^^                    T'*"' JK*'''""i*''"'- ''"' "• •^•'1^.^ l^ji - A/'^3*-"".

-------
    MULTIMEDIA TECHNICAL SUPPORT DOCUMENT

                    for  the

          ETHANOL-FOR-FUEL  INDUSTRY
                 Lee  M.  Thomas
                 Administrator
               Lawrence J.  Jensen
            Assistant Administrator
            for the Office  of Water
                James M.  Conlon
            Acting Director for the
   Office of Water Regulations and Standards
                Devereaux Barnes
Acting Director, Industrial Technology Division

                William Telliard
         Energy and Mining Branch Chief
                   March 1986
         Industrial Technology Division
   Office of Water Regulations and Standards
      U.S. Environmental Protection Agency
            Washington, D.C.  20460

-------

-------
                           DISCLAIMER


This Multimedia Technical Support Document was primarily based
on the EPA/EGD Multimedia sampling and  analysis program.   Data
were also obtained from NPDES permits,  an EPA Region  IV
Surveillence  and Analysis Division Program,  the IBRL-Ci Source
Test Evaluation, published literature and EPA supported
•engineering calculations.  No proprietary or confidential  data
appear or have been used in the preparation  of this document.
Although this document addresses various wastewater treatment
technologies, no process developer or process licensee was
involved in the development of this manual.  Mention  of trade
names or commercial products does not constitute endorsement or
recommendation for use.
                                 ii

-------

-------
                            FOREWORD
This Multimedia Technical Support Document (MTSD) provides
process, discharge and pollution control data in summarized form
for the use of permit writers, developers, and. other interested
parties." This document presents examples of control technologies
both as individual process units and as integrated control
train's.  These examples may be taken in part from applicable
NPDES or other permit applications and, therefore, reflect
specific plants.  None of the examples are intended to convey an
Agency endorsement or recommendation but rather are presented
for illustrative purposes.  The selection of control tech-
nologies for application to specific plants is the exclusive
function of the designers and permitters who have the flexi-
bility to utilize the lowest cost and/or most effective ap-
proaches.  It is hoped that the readers will be able to relate
their waste streams and controls to those presented in this
document to enable them to better understand the extent to which
various technologies may control specific waste streams and
utilize the information in making control technology selections
for their specific needs.

The reader should be aware that this document contains no
legally binding requirements or guidance, and that nothing
contained in this document relieves a facility from compliance
with existing or future environmental regulations, or permit
requirements.
                                111

-------

-------
                            ABSTRACT


This Multimedia Technical Support Document presents the
technical data base developed by the Effluent Guidelines
Division of EPA for the ethanol-for-fuel point source category.
Data were originally collected between 1979 and 1981 with the
intent of using them as the basis for proposing effluent
limitations guidelines.  However, in early 1982, an EPA policy
decision was made to develop guidance for the Ethanol-for-Fuel
industry instead of effluent limits.  This decision was made
because of the decline in the growth of this industry when
foreign crude oil became more available and the fuel shortage
was somewhat abated.

The ethanol-for-fuel industry is defined as those commercial-
size (greater than one million gallons of ethanol per year)
facilities that convert biomass (via fermentation) to ethanol
for use as a fuel.  On September 1, 1981 the ethanol-for-fuel
industry consisted of 15 such facilities with a total annual
capacity of 164 million gallons.  Thirty-five plants with a
total capacity of 705 million gallons per year were under con-
struction, and 42 plants with a total capacity of 980 million
gallons per year were proposed.  Approximately one-fourth of the
existing plants (in operation and under construction) were
direct dischargers (or discharging directly into a surface water
body).

In September 1985, there were 102 plants in 31 states, each with
a capacity of 1 million gallons per year or more.  Out of these
102, there were 57 plants in operation and producing, with
capacity of approximately 764 million gallons per year.  In 1985
there were 15 plants under construction in 12 states, with a
capacity of 220 million gallons per year.

This document discusses various sources of pollution generated
from the ethanol-for-fuel facilities on a multimedia basis:  for
air, water, and solid waste.  Also, various pollutants of con-
cern associated with each media waste stream are listed.  These
lists come from an extensive data gathering program also dis-
cussed in this document.  A presentation of pollution control
alternatives for each media waste stream is also included
followed by a discussion of costs for some of these control
systems.
                               v

-------
In regard to biomass sources, the pollution control strategies
discussed in this document for the ethanol-for-fuel industry
pertain to facilities that use grain, wood sugar, cane and cit-
rus molasses, and cheese whey as feedstocks.  Biomass sources
such as cellulose, sugar crops (i.e., sweet sorghum, sugar
beets, and sugar cane), and potatoes could not be addressed with
the information available at the time this document was
completed.
                               VI

-------
                          TABLE  OF  CONTENTS
                                                             Page

Disclaimer	»...	      ii
Foreword	\  \     m
Abstract   .	       v
Tables		      ix
Figures	  I    xiii

Section  1  Introduction  	       1
              1.1  Technology Overview	       2
              1.2  Regulatory Background  	       3
              1.3' Industry Overview  	       8
              1.4  Data Collection  Methodology  	       9
              1.5  Document Organization  	      10

Section  2  Industry Profile 	      12
              2.1  Historical Development   	      12
              2.2  Ethanol-For-Fuel Industry  Status   ...      15
              2.3  Ethanol-For-Fuel Process Description   .      33

Section 3  Waste Stream Characterization   	      52
              3.1  Data Collection	      52
              3.2  Statistical Data" Evaluation	      70
              3.3  Water Use and Effluent Source	      80
              3.4  Wastewater Characterization  .......      88
              3.5  Wastewater Pollutants of Concern   .  .  .     108
              3.6  Air Emissions	     130
              3.7  Solid Wastes	     146

Section 4  Wastewater Treatment and Control  Technology   .     157
              4.1  Background	     157
              4.2  In-Plant Source Control for
                    Wastewater Reduction  	     158
              4.3  Preliminary Treatment Technologies   .  .     166
              4.4  Primary Treatment Technologies  ....     171
              4.5  Secondary Treatment Technologies   .  .  .     173
              4.6  Tertiary Treatment	     182
              4.7  Disinfection	     186
              4.8  Sludge Handling .	     187

Section 5  Solid Waste Treatment and Disposal
           Technologies	     192
              5.1  Recycle/Reuse	     192
              5.2  Treatment Technologies  ...  	     194
              5.3  Disposal and Management Practices . .  .     196
                               vii

-------
                  TABLE OF CONTENTS (Continued)
                                                            Page
Section 6  Cost, Energy, and Nonwater Quality Aspects
           of Wastewater Treatment  	    198
             6.1  Model Plant Costing 	    198
             6.2  Treatment Options for Cost
                  Evaluation	    206
             6.3  Capital and Operation and
                  Maintenance Costs 	    208
             6.4  Non-water Quality Aspects  	    214

Glossary      	    222

References	    237

Bibliography  	    240

Appendix A  Sampling Procedures  .	    A~l

Appendix B  Analytical  Methods   	    B~l

Appendix C  Quality Assurance/Quality -Control Procedures.    C-l

Appendix D  Solid Waste and Air  Sampling Results   ....    D-l

Appendix E  Wastewater  Sampling  Results  	    E-l

Appendix F  Statistical Support  Calculations  	    F-l

Appendix G  Ethanol-for-Fuel  Effluent Guidelines
            Cost Manual	    G~l
                                viii

-------
LIST OF TABLES
Table
1-1
2-1
2-2
2-3
2-4

2-5
2-6

2-7

2-8

3-1
3-2
3-3
3-4
3-5
3-6
3-7

3-8

3-9

3-10

3-11

No.
THE CLEAN WATER ACT AMENDMENTS OF 1977 	
ETHANOL-FOR-FUEL FACILITIES (1981) . 	
ETHANOL-FOR-FUEL OPERATING PLANTS (1985) ...
PLANTS UNDER CONSTRUCTION (1981) 	
ETHANOL-FOR-FUEL PLANTS UNDER CONSTRUCTION
(SEPTEMBER 1985) 	 ...
PROPOSED PLANTS (1981) . „ 	 .
ENTANOL-FOR-FUEL PLANTS PROPOSED (SEPTEMBER
1985) 	 	
PROJECTED MAXIMUM ETHANOL PRODUCTION FROM
U.S. BIOMASS RESOURCES 	
ETHANOL-FOR-FUEL PLANTS BY STATE (SEPTEMBER
1985) 	 	
ETHANOL-FOR-FUEL DATA BASE SUMMARY 	
LIST OF 129 PRIORITY POLLUTANTS 	 	 .
CONVENTIONAL POLLUTANTS 	 	
NONCONVENTIONAL POLLUTANTS ANALYZED 	
EGD/EPA SAMPLING PROGRAM 	
DATA AVAILABLE FOR STATISTICAL ANALYSES ....
GROUPING OF FACILITIES BASED ON UNTREATED
EFFLUENT QUALITY ... 	
RELATIONSHIP BETWEEN ETHANOL FACILITIES AND
EVALUATION FACTORS FOR TSS 	 	
RELATIONSHIP BETWEEN ETHANOL FACILITIES AND
EVALUATION FACTORS FOR BOD5 	
RELATIONSHIP BETWEEN ETHANOL FACILITIES AND
EVALUATION FACTORS FOR FLOW RATIO 	
PERCENT VOLUME OF TOTAL UNTREATED EFFLUENT FOR
GRAIN DISTILLERS WITH BY-PRODUCT RECOVERY . . .
Page
6
16
17
20

23
24

27

29

32
53
56
61
62
64
72

74.

76

77

78

83

-------
LIST OF TABLES (Continued)
Table No.
3-12

3-13

3-14

3-15

3-16

3-17

3-18

3-19

3-20

3-21

3-22

3-23

3-24

3-25

3-26
3-27



SOLVENT STRIPPING COLUMN BOTTOMS FROM
DEHYDRATION SYSTEM/DISCHARGE VALUES 	
EVAPORATOR CONDENSATE CHARACTERIZATION:
PRIORITY POLLUTANTS 	
UNTREATED EFFLUENT ANALYSES SUMMARY — PRIORITY
POLLUTANT ORGANICS 	
UNTREATED EFFLUENT ANALYSES SUMMARY — PRIORITY
POLLUTANT METALS, . CYANIDE, AND ASBESTOS ....
UNTREATED EFFLUENT ANALYSES SUMMARY — CONVEN-
TIONAL POLLUTANTS 	
UNTREATED EFFLUENT ANALYSES SUMMARY — NONCONVEN-
TIONAL PARAMETERS 	
UNTREATED EFFLUENT ANALYSES SUMMARY — NONCONVEN-
TIONAL PARAMETERS 	 .' 	
UNTREATED EFFLUENT ANALYSES SUMMARY — NONCONVEN-
TIONAL PARAMETERS 	
TREATED EFFLUENT ANALYSES SUMMARY — PRIORITY
POLLUTANT ORGANICS 	
TREATED EFFLUENT ANALYSES SUMMARY — PRIORITY
POLLUTANT METALS, AND CYANIDE 	
TREATED EFFLUENT ANALYSES SUMMARY — CONVEN-
TIONAL POLLUTANTS 	 	 .
TREATED EFFLUENT ANALYSES SUMMARY — NONCONVEN-
TIONAL PARAMETERS ... 	
TREATED EFFLUENT ANALYSES SUMMARY — NONCONVEN-
TIONAL PARAMETERS 	
TREATED EFFLUENT ANALYSES SUMMARY — NONCONVEN-
TIONAL PARAMETERS 	
SETTLEMENT AGREEMENT EXCLUSION CRITERIA ....
TOXIC ORGANIC POLLUTANTS FOUND IN UNTREATED
EFFLUENT FROM ETHANOL PLANTS 	
X
Page

85

87

90

95

96

97

98

99

101

106

107

109

110

111
114

115
^^m

-------
                     LIST OF  TABLES  (Continued)

Table No.                                                    Page

 3-44     RCRA RELATED SOLID  WASTE ANALYSIS SUMMARY .  .  .    155

 3-45     ANALYTICAL PARAMETERS  ANALYZED FOR SOLID WASTE
          TESTING	    156

 4-1      BOD5 AND TSS REDUCTION ACHIEVED BY ETHANOL
          PLANT WASTEWATER TREATMENT  SYSTEMS.' 	    159

 4-2      TYPICAL INFLUENT WASTEWATER CHARACTERISTICS  AT
          GRAIN DISTILLERIES	    175

 5-1      TREATMENT AND DISPOSAL TECHNIQUES FOR  ETHANOL
          PLANT SOLID WASTES	    193

 6-1      ETHANOL-FOR-FUEL PLANT SIZE DISTRIBUTION  .  .  .    200

 6-2      UNTREATED EFFLUENT  CHARACTERISTICS USED IN THE
          DESIGN AND COSTING  OF  WASTEWATER TREATMENT
          SYSTEMS FOR ETHANOL-FOR-FUEL PLANTS 	    201

 6-3      PRODUCTION AND WASTEWATER GENERATION DATA FOR
          BEVERAGE AND ETHANOL-FOR-FUEL  PLANTS  .....     203

 6-4      SUMMARY OF MODEL PLANT CHARACTERISTICS   ....     205

 6-5      BIOSLUDGE PRODUCED  DURING WASTEWATER TREATMENT
          FOR ETHANOL FACILITIES 	    207

 6-6      ASSUMPTIONS USED IN THE DESIGN OF THE  SOLID
          WASTE HANDLING SYSTEM  .............     209

 6-7      SUMMARY OF WASTEWATER  TREATMENT CAPITAL COSTS
          FOR NEW ETHANOL-FOR-FUEL FACILITIES 	     210

 6-8      SUMMARY OF WASTEWATER  TREATMENT CAPITAL COSTS
          FOR EXISTING ETHANOL-FOR-FUEL  FACILITIES   ...     211

 6-9      SUMMARY OF WASTEWATER  TREATMENT O&M COSTS  FOR
          NEW AND EXISTING ETHANOL-FOR-FUEL FACILITIES.  .     212

 6-10     ASSUMPTIONS USED IN SYSTEM  DESIGN .......     216

 6-11     ASSUMPTIONS USED IN COST ESTIMATION	     218

 6-12     COST OF SOLID WASTE HANDLING	     219

 6-13     SUMMARY OF WASTEWATER  TREATMENT ENERGY
          REQUIREMENTS FOR NEW AND EXISTING ETHANOL-
          FOR-FUEL PLANTS 	  .....     221

-------
                     LIST OF TABLES (Continued)






Table No.
3-28
3-29
3-30
3-31
3-32
3-33
3-34
3-35
3-36
3-37
3-38
3-39
3-40
3-41
3-42
3-43

CONTROL AND METHOD BLANKS ANALYSES/PRIORITY
CONCENTRATIONS OF TOXIC ORGANIC POLLUTANTS
FOUND IN TREATED EFFLUENT FROM ETHANOL PLANTS .
BIOLOGICAL TREATABILITY OF CHLOROFORM AND
PHENOL PRESENT IN ETHANOL PLANT WASTEWATERS . .
PRIORITY METALS PRESENT' IN UNTREATED ETHANOL
PRIORITY POLLUTANT METALS PRESENT IN UNTREATED
MAJOR SOURCES OF AIR EMISSIONS FROM AN
TOTAL HYDROCARBON (THC) AND BENZENE ANALYSES
PARTICULATE MATTER ANALYSIS AND SAMPLING DATA
FOR PLANT A03/CYCLONE ON DIRECT-CONTACT
SULFUR DIOXIDE AND NITROGEN OXIDE ANALYSIS
FOR PLANT A03/CYCLONE ON DIRECT-CONTACT
1980 EPA SAMPLING PROGRAM/AIR EMISSIONS
FUGITIVE VOC EMISSION RESULTS FOR PLANT A06 . .
FUGITIVE VOC EMISSION RESULTS FOR PLANT EOS . .
ESTIMATED PARTICULATE AND VOC EMISSIONS FROM
THE CURRENT AND PROJECTED ETHANOL-FOR-FUEL
FACILITIES AND SOLID WASTE STREAMS TESTED . . .
POLLUTANT PARAMETERS ANALYZED TO DETERMINE
RCRA EP-TOXICITY 	
117
118
123
124
125
126
133
135
136
137
139
141
143
144
152
154
                                xii

-------
                          LIST  OF  FIGURES
Figure
  No.                                                        Page

 2-1      PROJECTED .GEOGRAPHIC  DISTRIBUTION OF ETHANOL-
          FOR-FUEL PLANTS  IN  1990  BY U.S.  EPA REGIONS . .     30

 2-2      PROJECTED GEOGRAPHIC  DISTRIBUTION OF ETHANOL-
          FOR-FUEL PLANTS  BY  STATE.  .	     31

 2-3      PROCESS DIAGRAM  FOR CHEESE.WHEY PREPARATION . .     37

 2-4      CONVENTIONAL  DISTILLATION  	     41

 2-5      CONVERTED BEVERAGE  PLANT	     43

 2-6      CURRENT DISTILLATION  DESIGNS	     45

 2-7      DEHYDRATION WITH SOLVENT RECOVERY 	     47

 2-8      DEHYDRATION WITHOUT SOLVENT RECOVERY	     48

 2-9      PROCESS FLOW  DIAGRAM:  BY-PRODUCT RECOVERY  . .     50

 3-1      MAJOR  SOURCES OF WASTEWATER FOR ETHANOL
          FACILITIES	     81

 3-2      MAJOR  SOURCES OF AIR  EMISSION FOR ETHANOL
          FACILITIES.  ........ 	    132

 3-3      SOLID  WASTE STREAMS FROM ETHANOL PRODUCTION . .    149

 3-4      SOLID  WASTE STREAMS FROM PROCESS WASTEWATER
          TREATMENT	    150

 4-1      SCHEMATIC  FLOW DIAGRAMS OF EQUALIZATION
          FACILITIES.	    169

 4-2      PLANT  El3  AERATED LAGOON WASTEWATER TREATMENT
          SYSTEM	    177

 4-3      PLANT  A03  ACTIVATED SLUDGE WASTEWATER TREATMENT
          SYSTEM	    179

 4-4      PLANT  E17  TRICKLING FILTER WASTEWATER
          TREATMENT  SYSTEM	    181

 4-5      PLANT  EOS  ROTATING BIOLOGICAL CONTACTOR
          WASTEWATER TREATMENT SYSTEM ..... 	    183
                               XI11

-------
                          LIST OF  FIGURES
Figure
  No.

 4-6

 6-1


 6-2


 6-3
A TYPICAL SLUDGE HANDLING AND  DISPOSAL  SYSTEM

RATIO OF WASTEWATER GENERATED  TO ETHANOL
PRODUCED VERSUS ETHANOL PRODUCTION	
SCHEMATIC DIAGRAM OF TREATMENT OPTIONS
1 AND 3	  .  .  .  ,
SCHEMATIC DIAGRAM OF TREATMENT OPTIONS
2 AND 4	
Page

 189


 204


 213


 215
                              XXV

-------
                           SECTION 1

                         INTRODUCTION


The purpose of this document is to provide, guidance to permit
writers, industry, and the general public on multimedia
pollution control systems for the ethanol-for-fuel industry.
Information is provided on ethanol-for-fuel waste stream
characterization, process descriptions, and pollution control
options and costs on a variety of ethanol-for-fuel facilities.

The term "Ethanol-for-Fuel" in this document concerns only the
ethanol derived from biomass through fermentation.  Ethanol can
also be derived from ethylene and ethanol derived in this
fashion is called synthetic ethanol.  However, synthetic ethanol
is not considered as a source of ethanol for the Ethanol-for-
Fuel industry evaluations.  Fermentation ethanol was first used
as a fuel in the United States, in the late 1800's; in the early
1900's ethanol was used both in stationary and mobile combustion
applications.  By the end of World War II, ethanol production in
the United States totaled 600 million gallons per year.  Using
ethanol as a fuel decreased after the war and nearly disappeared
until the late 1970's when interest was renewed because of
concern over dependence on insecure foreign oil supplies.

In light of this potential new industry, in 1979 the Agency
initiated the gathering of data with the intent of proposing
multimedia environmental regulations on the ethanol-for-fuel
industry.  In January 1981, the Federal government cut back on
financial assistance for ethanol production.  This action, along
with high corn prices and a more stable supply of petroleum
resources, resulted in a steep cutback of ethanol-for-fuel
production.  In early 1982, the Agency reached the decision to
utilize the data gathered to provide guidance rather than issue
formal regulations on pollutant discharges in the ethanol-for-
fuel industry.

The Multimedia Technical Support Document  (MTSD) contains no
legally binding requirements, no regulatory standards and
includes no preference for process technologies or controls.
Nothing within this document binds a facility to accepting the
example control  technology(ies) nor relieves a facility  from
compliance with existing or future environmental regulations or
permits.

-------
1.1  TECHNOLOGY OVERVIEW

All fermentation alcohol plants employ four basic processes:
feedstock preparation, fermentation, distillation and de-
hydration.  A fifth process, byproduct recovery, is also
possible, but not necessarily included in all ethanol-for-fuel
plants.  Variations within the fermentation, distillation and
dehydration processes do not result in significant changes in
the quality or amount of emissions or effluents from a facility.
Both feedstock preparation and byproduct recovery process
variations have greater impact on the characteristics of the
generated wastes.

Feedstock Preparation

Feedstock preparation includes all steps in converting the raw
material to a saccharified mash.  Depending on the feedstock,
different methods of preparing the saccharified mash and for
removing valuable byproducts, such as germ or lignin, are
available.  The feedstock preparation techniques in use in the
existing ethanol-for-fuel industry include:  dry milling, wet
milling, wood sugar preparation, and cheese whey preparation.

Fermentation

The biological conversion of the saccharified mash by.yeast for
the production of ethanol can be rendered in continuous or batch
fermentation processes.  The grain and wood sugars are converted
into ethanol and carbon dioxide.  Other reactions also occur
producing small quantities of acetic acid, aldehydes and longer
chain alcohols.

Continuous and batch fermentation processes require temperature
control, agitation and pH control.  Fermentation is an exo-
thermic process and cooling is usually employed for temperature
control.  Depending on the choice of fermentation process,  the
fermented mash will vary with respect to yeast reclamation,
vessel residence time, live yeast concentration and ethanol
concentration.  These four parameters are closely interrelated
and require special attention for the maintenance of steady
state operation.

Distillation

In the distillation process the ethanol is removed from the
solids and most of the water.  The process variations in the
distillation chain are a function of desired product quality.
Those plants which produce potable as well as fuel-grade ethanol
include additional stills to remove nearly all organic con-
taminants (e.g., fusel oils and aldehydes) whereas new grass
roots ethanol-for-fuel plants are designed to minimize energy
requirements and wastewater generation.

-------
Dehydration

When a mixture of ethanol and water is distilled, a minimum
boiling point azeotrope is found.  At this point  ( 96 percent
ethanol) further separation of ethanol and water  is impossible
using simple distillation.  To produce anhydrous  ethanol, a
third compound, the dehydration agent, can be added to the
mixture to alter the azeotrope and subsequently permit the
removal of all water from the ethanol.  This is the most common
technique used in the dehydration of ethanol to be used as fuel.

Byproduct Processing

The method of byproduct recovery is dependent upon the feedstock
and the feedstock preparation technique employed.  The stillage
from the bottom of the beer still is often recovered as a
marketable, high-protein byproduct but may be discharged as
wastewater.  In some cases, the quantity and/or quality of
stillage does not warrant the capital expenditure required for
byproduct recovery, particularly if feedstocks other than grain
are used.  Those plants which do recover the stillage utilize
dewatering and drying processes such as cyclones, evaporators
and dryers for complete recovery of a dry solid.  Those plants
that do not recover stillage have a substantially higher
wasteload since the byproduct recovery system is  the major
contributor to total distillary wastes.

1.2  REGULATORY BACKGROUND

Wastewater Regulations

The Federal Water Pollution Control Act of 1972 established a
comprehensive program to "restore and maintain the chemical,
physical, and biological integrity of the Nation's waters"
[Section 101(a)].  By 1 July 1977, existing point source
industrial dischargers were required to achieve "effluent
limitations requiring the application of the best practicable
control technology currently available" (BPT) [Section
301(b)(A)].  Further, by 1 July 1983, these dischargers were
required to achieve "effluent limitations requiring the
application of the best available technology economically
achievable (BAT) which will result in reasonable  further
progress toward the national goal of eliminating  the discharge
of all pollutants" [Section 301(b)(2) (A)].  New  industrial
direct dischargers were required to comply with Section 306 new
source performance standards (NSPS), based on best available
demonstrated technology (BAD), and new and existing dischargers
to publicly owned treatment works (POTWs) were subject to pre-
treatment standards under Sections 307(b) and (c) of the Act.
While the requirements for direct dischargers were to be
incorporated into National Pollution Discharge Elimination
System (NPDES) permits issued under Section 402 of the Act,

-------
pretreatment standards were made enforceable directly against
dischargers to POTWs (indirect dischargers).

Although Section 402(a)(l) of the 1972 Act authorized the set-
ting of requirements on a case-by-case basis, Congress intended
that, for the most part, control re- quirements would be based
on regulations promulgated by the Administrator of the EPA.
Section 304(b) of the Act required the Administrator to prom-
ulgate regulations providing guidelines for effluent limitations
setting forth the degree of effluent reduction attainable
through the application of BPT and BAT.  Moreover, Sections
304(c) and 306 of the Act required promul- gation of regulations
for NSPS, and Sections 304(f), 307(b), and 307(c) required
promulgation of regulations for pretreatment standards. In
addition to these regulations for designated industry cate-
gories, Section 307(a) of the Act required the Administrator to
promulgate effluent standards applicable to all dischargers of
toxic pollutants.  Finally, Section 501(a) of the Act authorized
the Administrator to prescribe any additional regulations
"necessary to carry out his functions" under the Act.

On 27 December 1977, the President signed into law the Clean
Water Act of 1977 (P.L. 95-217).  Although•this law makes
several important changes in the federal water pollution control
program, its most significant feature is its incorporation into
the Act of several of the basic elements of the Settlement .
Agreement program for toxic pollution control.  Sections 301(b)
(2)(A) and 301(b)(2)(C) of the Act now require the achievement,
by 1 July 1984, of effluent limitations requiring application of
BAT for toxic pollutants, including the 65 toxic pollutants and
classes of pollutants which Congress declared toxic under Sec-
tion 307(a) of the Act.  Likewise, the EPA's programs for new
source performance standards and pretreatment standards are now
aimed principally at toxic pollutant controls.  Section 306(b)
includes a list of industrial categories for which these per-
formance standards should be developed.  Moreover, to strengthen
the toxics control program, Congress added Section 304(e) to the
Act, authorizing the Administrator to prescribe "best management
practices" (BMPs) to prevent the release of toxic and hazardous
pollutants from plant site runoff, spillage or leaks, sludge or
waste disposal, and drainage from raw material storage associ-
ated with, or ancillary to, the manufacturing or. treatment
process.

In keeping with its emphasis on toxic pollutants, the Clean
Water Act of 1977 also revised the control program for nontoxic
pollutants.  Instead of BAT for "conventional" pollutants iden-
tified under Section 304(a)(4) (including biochemical oxygen
demand, total suspended solids, fecal coliform, pH, and oil and
grease), the new Section 301(b)(2)(3) requires achievement, by 1
July 1984, of "effluent limitations requiring the application of
the best conventional pollutant control technology" (BCT).  The

-------
factors considered in assessing BCT for an industry include the
costs of attaining a reduction in effluents and the effluent
reduction benefits derived compared to the costs and effluent
reduction benefits from the discharge of publicly owned treat-
ment works [Section 304(b)(4)(B)].  For nontoxic, nonconven-
tional pollutants, Sections 301(b)(2)(A) and (b)(2)(F) require
achievement of BAT effluent limitations within three years after
their establishment or 1 July 1984, whichever is later, but not
later than 1 July 1987.   Table 1-1 summarizes these levels of
technologies, sources affected, and deadlines for promulgation
and compliance.

BPT, BCT, BAT, and NSPS have not been developed for the ethanol-
for-fuel industry.  This industrial category was not listed
among those in Section 306(b) of the Clean Water Agt.  Yet in
1979, when it appeared that the industry was growing at a rate
requiring regulatory control, the Agency initiated a regulation
development program.  However, by 1981 when projected growth of
the industry substantially declined, the Agency made the deci-
sion to develop guidance rather than regulations.  The dif-
ference between the two is that regulations are legally binding
standards that require compliance.  "Guidance" on the other hand
simply provides information which permit writers and industrial
developers can use (among other sources) in their determination
of appropriate pollution control measures.

Air Regulations

The Clean Air Act and its amendments created a comprehensive
program to protect and enhance the Nation's air quality and a
regulatory scheme for the control of air pollution.  The
cornerstone of the Act is the development of uniform national
ambient air quality standards  (NAAQS).  The responsibility for
limiting emissions to meet the ambient standards lies with the
states.  The Act required each State to develop state  imple-
mentation plans (SIPs) which provide for implementing, main-
taining, and enforcing the ambient standards.

The Act also requires the United States Environmental Protection
Agency to establish three sets of nationally uniform emission
limitations:  new source performance standards (NSPS), hazardous
pollution emission standards, and motor vehicle emission stand-
ards.  The NSPS requires the application of "best demonstrated
technology" to new and modified stationary sources.  However,
the Act allows the States to require more stringent emission
limitations than those developed for NSPS.

Part C of the Act, prevention of significant deterioration of
air quality, provides EPA a means to regulate any pollutant from
any major emitting facility which may adversely affect the pub-
lic health and welfare.  A major emitting facility for the
ethanol-for-fuel  industry would be any source which emits or has

-------
                          u
                          o
                         JJ
                          CO
                          J-l
                          
              r-l
               3
              "-3
        CO
        cn
        t-i
a>
01
60
Cfl
< C
CU O
Ez2 *H
JJ
O 60
U-l i— 1
3
cu e
B 0
1-1 u
•o
to h
0) O
CU-I
CO
CO
CO
o.
Jj
cu
JJ
UH
to

(-1
^•l

•-4
0)
60
CO
CO
CO
co
o.
u
cu
JJ
U-l
to

p
^^

i-H
cu
o^
(0
(fl
(0
id
0<
J.J
0)
4-1
M-l
id

£
K^

H
                            t)
                            CU
                            JJ
                            u
                            co
                            O)
                            o

                            3
                            o
                            CO
        co
        01
        ej

        S
        O
        CO

        60
 co
 0)
 U

 3
 O
 co

 60


 JJ
 CO
 §
 CO

 S1
•r)
 to
•H
o
Vi
Q.
e
a
3
0)
>

JJ C
O O
0) -H
U-l JJ
U-l Cfl
W 60
0)
JJ
tu
CO
.
CO
JJ
>> 0)
60
co co
--. CO
t-H CO
1 S
•—4 O.




co
0)
o
tu
3
O
CO

cu
z
to
j-i
CO
O)
CO

e
^j

^j
CU
JJ
CO
iH

O
Z

JJ
CU
JJ
ll 1
*w
CO

CO
^
CO
'O

o
r*.
CN
co
0)
u
VJ
3
O
CO

60
e
•H
JJ
CO
i-l
^
U
O
1-1
JJ
CO
60
3
O

Q,

fci
(U
JJ
U-l
CO







0)
60
Cfl
co
co
S.

o
JJ

60

•H
60

CO

"S s
co H
•H 0
•O Du
iH
e
0
CL,
O
a
, 3
O>
>
i-l
jj g
CJ O
0) i-l
U-l JJ
UJ (0
W W)
01
JJ
U-4
Cfl
.
CO
l^
>s CU
60
CO CO
^- co
-H CO
JL a
log
i-l o
•O Pu

CO O
0) JJ
u
IJ 60
3 C
0 i-l
CO 60
l-i
S CO
01 J=
Z CJ
                           UH
                            o


                            o
                           •H
                           JJ
                            U
                            0)
                           CO
                                  •3-
                                  O
       O
       CO
              o
              co
o
CO
                      o
                      n
o
co
                               o
                               CO
                           o
                           CO
                                 r-
                                 O
                                 co
 oc
 o


1
 01
H
                                  H
                                  Oi
                                  03
                 1
                                                                     en
                                                                     co
                                                                     0-
                                                                                  to
                                                       CO
                                                       CU
                            
-------
 the  potential  to  emit  227  metric tons/year (250 tons/year)  or
 more of  any pollutant.

 Solid Waste Regulations

 The  issue of federal legislative control  for  the safe  disposal
 of solid waste  has  been  a  primary environmental concern in  the
 1970's.  Initially, regulation  of solid waste was solely the
 responsibility  of the  states.   Later,  federal solid  waste pro-
 grams were promulgated such  as  the Solid  Waste Disposal Act of
 1965 and the Resource  Recovery  Act of  1970.   However,  neither of
 these acts gave any enforcement authority for solid  waste con-
 trol to  the federal government.   In order to  obtain  more uniform
 solid waste control the  Resource Conservation and Recovery  Act
 (RCRA) was passed in 1976.

 RCRA was designed with the following principal features:
 regulation of certain wastes, defined  or  characterized  as
 hazardous, are  to be the responsibility of the federal
 government; and regulation of nonhazardous wastes is to be  a
 state responsibility,  in  conformance  with federal guidelines.
 However, under RCRA Section  3006,  states  are  authorized and
 encouraged by EPA to develop and carry out their own hazardous
 waste programs in lieu of a  federally  administered program.
 Authorization for state  run  programs must be  granted by EPA and
 is being initially administered  through an "interim  status"
 program.  "Final  authorization"  will be possible after  Section
 3004, Part 264 requirements  are  promulgated.

 For solid wastes, the prevailing  factor is whether the  waste  is
 considered hazardous or  nonhazardous under the Resource Con-
 servation and Recovery Act.  If  one  or more of  the solid waste
 streams  generated by ethanol-for-fuel  facilities are considered
 hazardous, the Administrator has  the authority  to  "list"  such
 streams.  When this occurs the  generators, transporters,  and
 disposers of these wastes must comply  with all  appropriate
 Subtitle C regulations of the Resource Conservation and Recovery
 Act (RCRA 3000 Series).  Wastes which  are  not  hazardous  are
 subject  to Subtitle D regulations  (RCRA 4000  Series).

 Additionally, there are  regulations  which  deal  with the reuse  of
 hazardous wastes.  Under Section  3001, part 261.6, a hazardous
 waste which meets specific criteria  is excluded  at this  time
 from some of the waste management  requirements  if  it is  always
 used, reused, recycled,  or reclaimed.

 Prior EPA Regulations

The ethanol-for-fuel industry consists of  facilities that con-
vert biomass to ethanol  for use as a fuel.  It  is  a new  industry
which,  for the most part, consists of converted  beverage  alcohol
plants.   A review of environmental regulations reveals  that

-------
there are no federal regulations which apply specifically to the
effluents, emissions, or solid wastes generated by either
ethanol-for-fuel facilities or beverage alcohol facilities.  In
the absence of effluent guidelines, National Pollutant Discharge
Elimination System (NPDES) permits have been issued to dis-
tillers based on a permit authority's "best professional
judgment" under authority of Section 402(a)(l) of the Federal
Water Pollution Control Act. Also, state pollution control
boards have been responsible for monitoring and regulating air
emissions and solid wastes for existing ethanol facilities based
on "best professional judgment."

1.3  INDUSTRY OVERVIEW

As of September 1981, there were 15 plants which comprised the
ethanol-for-fuel industry.  The combined capacity of these
plants was 600 million liters  (163.5 million gallons) of ethanol
per year.  At that time there were six beverage alcohol plants
being converted to produce ethanol-for-fuel and 29 new facili-
ties under construction.  The plants under construction were
estimated to have a capacity of about 2.5 billion liters per
year (705 million gallons per year); most of these plants were
scheduled to be on-line by 1985.   In addition, there were 42
plants under study or planned.  The combined capacity of these
proposed plants was approximately  4.3 billion  liters per year  (1
billion gallons.per year).

In January 1984, a total of 70 ethanol-for-fuel plants were in
existence.  Of  these 70, however,  only 43 were operational.  The
capacity of these 70 plants was approximately  2.6 billion liters
per year  (683 million gallons  per  year).  (1)   An  industry
profile later performed in September 1985 showed a total of 102
ethanol-for-fuel plants in existence.*  Of these, 57 were in
operation and producing.  The  total capacity of the 102 plants
was 3.6 billion liters per year  (941 million gallons per year).
The 57 operating plants had a  capacity of 2.9  billion liters per
year  (764 million gallons per  year).  At  this  time, there were
also 15 plants  under construction  in 12 states with a capacity
of approximately 220 million gallons per  year.  .There were 38
proposed plants (capacity of 593 million  gallons per year) with
another  36 projects  "on hold."
 *Note:   All  the  data collection,  literature  searches,  analyses,
 statistics,  and  costing for this  document were completed in
 1981.   Prior to  publication in 1986,  however,  an updated
 industry profile (September 1985)  was included in this document
 for informational purposes.  EPA  believes, however,  that the
 industry has not changed significantly enough  in the past four
 years  to warrant an entire reanalysis of the 1981 data.
                                8

-------
Grain  is  the major  feedstock  for  these  facilities.   Approximate-
ly 94  percent of  the alcohol  from the plants  under  construction
will be derived from grain.   The  remaining  ethanol  will  be  pro-
duced  from wood sugars, corn  syftip,  and other biomass  sources.

In the late 1800s,  fermentation ethanol was used  for cooking,
heating,  and lighting.  During World War  II,  ethanol was used
for fuel  in submarines, aircraft,  and land  vehicles, as  well as
in the production of synthetic rubber.  However,  after the  war,
gasoline  became plentiful and inexpensive,  and industrial
ethanol was produced by a more economical method  using ethylene.
The interest in fermentation  ethanol was  renewed  by the  Nebraska
legislature in 1971 when the  state tax on gasoline  was reduced
for fuels containing grain-derived ethanol.   Public interest
continued, and the  Department of  Energy,  United States Depart--
ment of Agriculture, White House,  and Congress were-encouraging
research  and development of ethanol  for fuels.

1.4  DATA COLLECTION METHODOLOGY

To compile a data base for the evaluation of  pollution control
in the ethanol-for-fuel industry,  information was gathered  from
the literature; beverage and ethanol-for-fuel facilities; trade
organizations such as the Distilled  Spirits Council of the
United States (DISCUS), the National Gasohol  Commission,  the
National  Alcohol  Fuels Commission, and the National Alcohol
Fuels Producers Association; and  government agencies such as the
DOE, EPA, and Bureau of Alcohol,  Tobacco, and Firearms (ATF).
Data obtained from  these sources  included information  on  ethanol
production; location and distribution of ethanol-producing
facilities; process descriptions;  water use;  sources of  waste-
water, air emissions, and solid wastes; pollutant concentra-
tions; and cost and treatability  of  control and treatment
technologies.
                  f
The data base collection efforts  included contacts  with govern-
ment and  industry personnel, a program for sampling eight
ethanol distilleries, and preparation and submittal of two
industry  questionnaires to 15 distilleries under authority of
Section 308 of the Clean Water Act,  Sections  111 and 114  of the
Clean Air Act, and Section 3007 of RCRA.  Also conducted  as part
of the data gathering effort was a review of  the NPDES moni-
toring data on file with regional  EPA offices., and  a review of
the information contained in the  1974 draft development docu-
ment for  the Beverages Segment of  the Miscellaneous  Food  and
Beverage  Industry concerning the beverage alcohol industry.

After the data base was analyzed,  the major sources of waste-
water, air emissions, and solid wastes were identified and their
contribution to total plant waste  load quantified.  The total
plant wastewater  characteristics were summarized in terms of
pollutant concentration for the toxic (129 priority pollutants),

-------
conventional, and nonconventional pollutants.  Also, point
source and fugitive air emissions were estimated for criteria
pollutants (NOx, SOX' an<* particulates) and volatile organic
compounds on a plant-by-plant and industry-wide base.  Finally,
all solid wastes, plant feedstocks, and by-products were evalu-
ated for the characteristics of ignitability, corrosivity,
reactivity, and EP-toxicity.

The determination of wastewater pollutants of concern was based
on toxicity of pollutants, wastewater characteristics and the
treatability of these species by control and treatment
technologies.

The control and treatment technologies applicable to the indus-
try were assessed.   Included were in-plant and end-of-pipe  tech-
nologies which are used in the industry or can be adapted to it.
The identified technologies were evaluated for their ability to
treat the pollutants of concern.  The problems, limitations, and
reliability of each  control and treatment technology were also
identified.

In addition to treatability, the cost of treatment has been con-
sidered  in developing pollution control systems.  Thus,  this
document includes an evaluation of  the cost associated with
purchase,' installation, and operation of wastewater  treatment
equipment.  Capital  costs, annual costs, energy requirements,
and land requirements were developed for new plants  and  for
retrofitting existing plants.  Cost information was  obtained
from  the industry during  plant visits, from engineering  firms,
from  equipment suppliers, and from  the literature.   Where data
were  lacking, costs  were  developed  from knowledge of necessary
equipment, processes employed, and  construction and  maintenance
requirements.

1.5   DOCUMENT ORGANIZATION

This  Multimedia  Technical Support  Document  is  presented  in  seven
sections and seven appendices.   Following this  introductory
section  are:

      Section 2  - Industry Profile  - The  industry  profile con-
      tains  information  on the history  of ethanol  production,
      process descriptions,  total plant capacities,  and  other
      important  statistics,  as well  as  water  use  and  management
      practices  within  the ethanol-for-fuel  industry.   This
      profile provides  a foundation for analysis  of  water use
      and wastewater  generation  and treatment.

      Section 3  - Waste Stream Characterization -  The data col-
      lected  on  the levels of  pollutants  in  air emissions,  waste-
      waters and solid  wastes  from  ethanol  facilities is sum-
      marized and evaluated  in Section 3.   Included  are  the  test

                                10

-------
results from two EPA sampling programs and monitoring data
obtained from several distilleries.  Also included is a
discussion of the major sources of emissions and effluents
and their composition and treatability.

Section 4 - Wastewater Treatment and Control Technology -
This section discusses applicable in-plant and end-of-pipe
technologies which can be used to reduce or eliminate the
pollutants of concern.  The achievable effluent pollutant
reductions are discussed using treatability information
from the beverage alcohol and ethanol-for-fuel industries.
 The applicable technologies are further analyzed according
to their cost effectiveness, energy requirements and
secondary pollutant potential.
Section 5 - Solid Waste Treatment and Disposal Technologies
- This section discusses applicable solid waste treatment
and disposal techniques including dewatering, drying, di-
gestion, land application and recycle/reuse.  These tech-
niques are analyzed based on effectiveness, availability,
current use and cost.

Section 6 - Cost, Energy and Nonwater Quality Issues -
Cost, energy and nonwater quality issues are discussed for
each .treatment technology.  Cost and energy information
contained in this manual was obtained from industry during
plant visits, from engineering firms, from equipment
vendors, and from the literature.

References.

Appendix A - Sampling procedures used to collect field
wastewater, solid waste and gaseous emissions.

Appendix B - Analytical methods and preliminary sample
treatment on preparations used to analyze the collected
samples.

Appendix C - Quality assurance/quality control procedures
to assure, assess and document the precision, accuracy, and
adequacy of the data.

Appendix D - Solid waste and air sampling results -
compilation of analytical data.

Appendix E - Wastewater sampling results - raw and treated
effluent analytical data.

Appendix F - Statistical support calculations.

Appendix G - Appendix G is the Ethanol-for-Fuel Effluent
Guidelines Cost Manual which presents a detailed evaluation
of the costs and energy requirements associated with treat-
ment and control alternatives discussed in this manual.
                          11

-------
                             SECTION 2

                         INDUSTRY PROFILE
This profile of the ethanol-for-fuel industry consists of a
short historical background on the ethanol industry; status of
the industry, including information on production capacity,
location/ number of plants, feedstocks, by-products, and plant
age or on-line dates for proposed plants; and a discussion of
ethanol-for-fuel processes.

2.1  HISTORICAL DEVELOPMENT

The production of ethanol originated with the discovery that
alcoholic beverages could easily be obtained by fermenting sub-
stances with naturally occurring sugars such as fruit.  The pro-
duction of ethanol from grain is a more complex process because
the starch must be converted to sugar before fermentation; how-
ever, even this technique was known in ancient times.  The
Egyptians and Mesopotamians brewed beer as early as 2500 B.C.,
and these processes were used until the middle 1800's when
modern fermentation techniques were developed by Kutzing and
Pasteur.

In the late 1800's, fermentation ethanol was used in the United
States for cooking, heating, and lighting because it provided
clean and odorless fuel.  Henry Ford built a Model A car in the
early 1900's with an adjustable carburetor enabling the car to
be powered by pure ethanol, gasoline, or any mixture of the two.
By the 1930's, ethanol fuels were widely used in the United
States and 40 other nations, and an estimated four million cars
were powered by ethanol fuels in Europe (2).

With the advent of World War II and the subsequent scarcity of
oil, there was even more reliance on ethanol fuels.  The Germans
powered their war machinery with ethanol derived mostly from
potatoes when their oil supply was severed.  Also, in the United
States, whiskey distilleries and newly built ethanol facilities
supplied ethanol for use in submarines, aircraft, and land
vehicles.  In addition, ethanol was used as a feedstock in the
developing synthetic rubber industry.  In 1944, U.S. ethanol
production totaled 600 million gallons, half of which went for
synthetic rubber (3).

After the war, many distilleries were dismantled or converted to
beverage plants.  Gasoline became plentiful and inexpensive, and

                                12

-------

-------
industrial ethanol needs could easily be met by the new, more
economically produced synthetic ethanol that was .derived from
ethylene.  By 1949, only 10 percent of industrial ethanol was
produced from grain (3).  In 1979, industrial ethanol con-
stituted over 60 percent (more than 300 million gallons per
year) of the ethanol produced in the United States.

In the 1970's, there was a renewed interest in ethanol from
biomass, sparked by concern about increased U.S. dependence on
insecure foreign oil supplies and an interest in finding
alternative uses for agriculture products.  It was not until
1979, however, that this renewed interest resulted in any
significant use of ethanol for motor fuel.

The Nebraska state legislature acted in 1971 to reduce the
state's gasoline tax by 3 cents per gallon for fuels containing
at least 10 percent agriculturally derived ethanol, but this had
little impact on ethanol consumption.  The Arab oil embargo in
1973-74 stimulated additional interest in ethanol as world crude
oil prices suddenly increased by nearly 400 percent.  In spite
of this large increase in oil prices, economic studies showed
that ethanol from biomass would not be economically viable
without a large subsidy.  However, support for using ethanol as
a motor fuel continued to grow among agriculture states.  Iowa
provided an excise tax exemption for ethanol/gasoline blends and
developed a marketing program.  Illinois joined in support and
conducted tests of these fuel blends in state vehicles.  Fleet
tests were performed in Nebraska and Iowa.  Sales of ethanol on
the market began in Illinois in January 1978, at three retail
stations.  By mid-1978 market sales began in Iowa, and in
November 1978, 60,850 gallons of ethanol were sold as motor fuel
in that state (3).

By late 1978 the grassroots support for ethanol resulted in con-
gressional action.  The Energy Tax Act of November 1978 provided
that ethanol/gasoline blends were exempt from the 4-cents-per-
gallon federal excise tax on motor fuel from 1 January 1979
through 1 October 1984.  The exemption applied to blends con-
taining at least 10 percent ethanol produced from other than
petroleum, natural gas, or coal; the exemption had the effect of
providing a subsidy for ethanol of 40 cents per gallon (4 cents
for each one-tenth of a gallon of ethanol included in an
ethanol/gasoline blend).

The interruption of crude oil exports by Iran in early 1979 led
to serious gasoline shortages in the U.S. and an increase of
over 100 percent in world crude oil prices.  The gasoline
shortages and rapid oil price increases created a sense of
urgency for U.S. efforts to reduce dependence on foreign oil,
and it was concluded that ethanol from biomass was the only
                                13

-------
 alternative fuel that could provide a substitute for OPEC oil in
 the short-term.  By mid-1979, ethanol/gasoline blends were sold
 in over 800 retail outlets in 28 states, and a large demand for
 ethanol developed.

 The crisis atmosphere of 1979 resulted in a host of government
 actions (both federal and state) to encourage production of
 ethanol-for-fuel from biomass as rapidly as possible.  These
 initiatives included exempting ethanol/gasoline blends from
 gasoline taxes by many states, extension of the federal excise
 tax exemption, and initiation of a variety of federal grant and
 loan guarantee programs.

 The rapidly increasing gasoline prices and the tax  exemptions
 for ethanol/gasoline blends induced additional firms to produce
 ethanol for fuel.   The initial production came entirely from
 plants  which had been producing ethanol for beverage or indus-
 trial uses.   A wave of announcements of plans for new or
 expanded ethanol-for-fuel plants occurred after enactment of the
 Crude Oil  Windfall Profits Tax in April 1980, which extended the
 4-cents-per-gallon federal excise tax exemption for ethanol/
 gasoline blends  from 1984 through 1992.   Many other organiza-
 tions indicated  that they were studying plant feasibility or
 applying for government  loans  or loan guarantees  for their
 plants.   Hundreds  of potential ethanol-for-fuel plants  were  in
 various  stages of  study  or planning  by mid-1980.

 In  January  1981, the  Reagan Administration  announced that  it  was
 proposing  to cut back  on financial  assistance for ethanol
 production,  as part  of its  efforts  to  curtail federal spending.
 Tne Administration  proposed to rely  primarily on  the federal
 excise  tax exemption  to  support  ethanol-for-fuel  production.
 This action,  along  with  unusually high corn prices  and  a weak
 gasoline market, resulted  in reconsideration  of decisions  to
 proceed  with many projects.  Construction was halted on some
 projects, some existing  plants reduced ethanol production  or
 decided  not  to start production, and many plans for  new plants
were put on hold pending further analysis or  resolution of
 financing issues.

 In  addition  to federal excise  tax exemption, many states
exempted ethanol-for-fuel from state taxes.    in thirty-four
states,  ethanol-for-fuel was exempted  from all or part of  state
fuel taxes.  With lower grain prices in 1984, and state tax
exemptions and federal tax exemptions, the ethanol-for-fuel
industry has continued to grow.
                               14

-------
2.2  ETHANOL-FOR-FUEL-INDUSTRY STATUS

2.2.1  1981 PRODUCTION LEVELS

The ethanol-for-fuel industry is defined as commercial-size
facilities (capacity greater than one million gallons of anhy-
drous ethanol per year) which convert biomass (via fermentation)
to ethanol for use as fuel.  By September 1981, the ethanol-for-
fuel industry was composed of 15 plants with a combined produc-
tion capacity of about 164 million gallons of ethanol per year.
These plants are presented in Table 2-1.

Eight of these plants are grassroots facilities, six were con-
verted from beverage alcohol facilities, and the remaining plant
is an industrial grade ethanol facility.  A variety of feed-
stocks are used which include grain, grain-derived high fructose
corn syrup (HFCS) from corn sweeteners, wood sugars from wood
pulping operations, and cheese whey.  All the facilities, with
the exception of the plant which processes wood sugars, sell
their by-products, either wet or dry, as livestock feed.  The
plant which processes wood sugars concentrates  its by-product
lignin stream and then sends it to a lignin processing facility.

Approximately 60 percent of .the 1981 ethanol-for-fuel capac-
ity is from former beverage distilleries or from expansion of
facilities previously used for industrial, medical, or beverage
alcohol production.  Grains such as corn, wheat, and milo are
the major feedstock and account for over 96 percent of the
ethanol produced.  Natural gas or oil  is used as the heat source
for most of the current ethanol-for-fuel plants, although there
are plans to convert some  plants to coal.  The  plants are dis-
persed around the country, but over two thirds  of  the capacity
is located  in the central  region of the country.

2.2.2   1985 PRODUCTION  LEVELS

By September 1985,  102  ethanol-for-fuel plants,  each with a
capacity of  1 million  gallons  per year or greater, were  located
in 31  states.   Of  these,  57 were operating  and  45  non-operating.
Total  production capacity  was  approximately  3.6 billion  liters
per  year  (941 million  gallons  per year).   Capacity of  the  57
operating  plants was  2.9  billion  liters per  year (764 million
gallons  per year)  as  shown in  Table  2-2.

Production of  ethanol  for fuel had  expanded  rapidly  as  shown  by
the  following  yearly  production  figures.  (37)
                                15

-------
                             Table 2-1

                   ETHANOL-FOR-FtJEL' FACILITIES
                              (1981)
Plant
Code
A01
A02
A03

A04
A05
A06 .
A07
A08
A09
A10
All

A12
A13
A14
A15
Capacity
(MM qal/yr)
60
20
3
.
10
3
3
2
1.2
1.2
2
1

1
2.5
8.6
45
Location
IL
PA
KS

IL
IA
AR
WA
AL
NC
WI
WA

SD
IA
GA
IA
Feedstock
HFCS*
Corn
Corn, Milo,
Wheat
Corn
Milo
Corn
Wood Sugars
Corn
Corn, Milo
Cheese Whey
Corn,
Potatoes
Corn
Corn
Corn
Corn
*High fructose corn syrup.
                                 16

-------
                             Table  2-2

                 ETHANOL-FOR-FUEL OPERATING  PLANTS
                              (1985)
 State

 Arkansas
 California
Colorado


Idaho

Illinois
Indiana
Iowa
(476)
Kansas

Kentucky
Louisiana
Minnesota

Montana

Nebraska

New Jersey
New Mexico
(594.8)

North Dakota
 Location

 Van  Buren
 Selma
 Winters

 Cueamonga
 Corona
 Golden

 Monte Vista
 Heyburn

 Rockford
 Decatur
 Peoria
 Pekin
 Batavia
 Pekin
 South Bend
 Cedar Rapids
 Muscatine
 Bonaparte
 Clinton
 Hamburg
 Elgin
 Atchison
 Garden City
 Franklin
 Jennings
 Port Allen
 Belle Chasse

 Shrevport
 Melrose
 Mankato
 Ringling
 Amsterdam
 Roc a
 Hastings
Windsor
 Clovis
 Clovis
 Tucumcari
Walahalla
(Thous.  gal/yr)

     3,000
    10,000
     1,000

     5,000
     2,000
     2,400

     4,000
     3,000

     3,000
   150,000
    90,000
    70,000
     2,000
    11,000
    50,000
    60,000
    10,000
     4,000
    20,000
     5,000
     1,500
     6,000
     1,750
    20,000
    25,000
     4,000
     7,000

     2,000
     1,000
     2,000
     1,500
     1,850
     1,500
    11,000
     1,000
     1,200
     1,500
     4,500
    11,200
 Feedstock

 Corn
 Molasses
 Industrial
  Wastes
    »
 Cheese Whey
 Brewery
  Condensate
 Potato
 Potato Waste
  & Hulls
 Corn
 Cornstarch
 Corn
 Corn
 Sugary Wastes
 Corn
 Corn
 Corn
 Corn
 Corn
 Corn
 Corn
 Corn
 Corn
 Corn
 Corn
 Molasses
 Molasses
 Blackstrap
  Molasses
 Milo
 Cheese Whey
 Hydrous Ethanol
 Barley
 Barley
 Milo
 Corn
Waste Sugar
 Milo
Milo
Milo  .
Barley
                               17

-------
                      Table 2-2 (Continued)
                ETHANOL-FOR-FUEL OPERATING PLANTS
                              (1985)
Oklahoma
Pennsylvania
Tennessee
Texas
Utah
Virginia
Washington

Wisconsin
Location

South Point
Navarre

Hydro
Wadsfordsburg
Loudon
Euless
Tremonton
Reston
Charles City
Floyd
Nelson
New Church
Chesapeake
Wilsons
Charles City
Bellingham

Jim Falls
Juneau
(Thous.  gal/yr)

    60,000
     1,000

     5,000
     1,650
    40,000
     5,000
     2,500
     5,000
     6,000
     7,000
     2,600
     1,600
     6,600
     1,000
     1,650
     2,500

     1,500
     2,000
Feedstock

Corn
Agricultural
  Wastes
Milo
Corn
Corn
Milo
Barley
Hydrous Ethanol
Hydrous Ethanol
Hydrous Ethanol
Hydrous Ethanol
Corn
Hydrous Ethanol
Corn
Corn
Sulfite Waste
  Liquor
Corn
Cheese Whey
                               18

-------
                              Actual Production
           Year             (In millions of gallons)

           1979                      20
           1980                      40
           1981                      75
           1982                     210
           1983                     375
           1984                     430
           1985                     625 (est. from 3 quarters)

2.2.3.  PLANTS UNDER CONSTRUCTION (1981)

In 1981 35 ethanol-for-fuel plants were under construction; six
of these plants were beverage plants undergoing conversion and
the remaining 29 were grassroots facilities.  Seventeen of the
plants under construction were scheduled to be on-line by 1980,
the rest were scheduled to be operational by 1982.  These plants
are summarized in Table 2-3.

The total capacity for these 35 plants was about 705 million
gallons per year, over one-third (259 million gallons) will be
produced by converted beverage alcohol facilities.  Approxi-
mately 81 percent of the ethanol will come from facilities which
produce 20 million gallons per year or more.  The size distri-
bution for plants under construction is presented below.

     Range (million gallons/year)       Number of Plants

                 1-5            ,               16
                 6-15                          10
                16-35                           4
                36-75                           3
                 >75                            2

Grains such as corn, wheat, milo, and barley are the predominant
feedstock and accounting for almost 94 percent of the designed
ethanol production.  Sugar feedstocks such as sugarcane, sugar
beets, and molasses were projected to provide about seven
percent of the ethanol.  Potatoes were projected to provide less
than 1 percent of the ethanol from plants under construction.

The plants were to be located in 20 states and dispersed in
almost all regions of the country.  Almost half of the capacity
for plants under construction in 1981 were located in the
midwest.

2.2.4  PLANTS UNDER CONSTRUCTION (1985)

In September 1985, 15 ethanol-for-fuel plants were under
construction.   These facilities have a combined capacity of 833
million liters per year (220 million gallons per year).  All

                               19

-------
Code No.
                             Table 2-3

                     PLANTS UNDER CONSTRUCTION
                              (1981)
Location
  Ethanol
Production
Feedstock
On-Line Date

C01*
C02
COS
C04
COS
C06
C07
COS
C09**
CIO
Cll
C12
CIS
C14
CIS
C16**
C17**
CIS

IL
LA
OH
IL
GA
IA
TN
LA
IL
KY
CO
NC
OK
• sc
ID
IN
KY
IN
(MM gal/yr)
190
120
60
60
10.5
10
40
34.6
21.5
21
8.5
25
12
11
4
8
8
6

HFCS
Corn
Corn
Corn
Corn
Corn
HFCS
Sugarcane,
Molasses
Corn
Corn
Grain,
Sugar Beets
Corn
Milo
Corn
Corn
Corn
Corn
Corn

Late 1981
Mid 1982
Mid 1982



1982
1982
Mid 1981
Jan. 1982


June 1981
Late 1982

1981

Spring 1982
 *Expansion of plant A01.
**Converted beverage alcohol facilities.
                                20

-------
Code No.
Location
  Table 2-3 (Continued)

PLANTS UNDER CONSTRUCTION
          (1981)

         Ethanol
    Production    Feedstock
On-Line Date

C19**
C20**
C21
C22
C23
C24
C25
C26
C27
C28
C29
C30
C31
C32
C33
C34
C35

KY
KY
ND
KS
MN
KY
CO
IA
MD
IA
CO
IN
OR
WI
OH
WI
WA
(MM gal/yr)
. 6
5.5
3.5
6
4
3.5
3
5.4
2.5
2.5
2.5
2
1.8
1.5
1.2
1
1

Grain
Corn
Potatoes
Milo
Wheat,
Barley
Corn
Milo
Corn
Corn, Barley
Corn
Barley,
Potatoes
Corn
Grain
Corn, Pota-
toes
Corn
Corn
Corn

1981
1981


Early 1982
1981
1981

Nov. 1981
. —
Jan. 1982
1981
1981
1981
1981
1981
—
**Converted beverage alcohol facility,
                                21

-------
of these new plants are grass roots facilities.  Plants are
located in 12 states as shown in Table 2-4.   Corn and other
grains will be the predominant feedstock of these new facilities
with 96 percent of production coming from grains.  The other 4
percent will be produced from other feedstocks,  including cheese
whey.  One plant will be operating to dehydrate hydrous ethanol.

2.2.5  PROPOSED PLANTS (1981)

In 1981 there were 42 proposed ethanol-for-fuel plants.  These
are presented in Table 2-5.  Two to three years are needed for
the construction of a facility.  Site location, funding, and
economic incentives  determine how many of these plants will
actually be built.  With the interest in ethanol fuels and
availability of various feedstocks, in 1981 it was expected that
many of these plants would be on,-line by December 1985.  The
combined production capacity of the proposed plants is about 980
million gallons per year, with the plants falling into the
following ranges:

     Range (million gallons/year)       Number of Plants

                 1-5                             7
                 6-15                          11
                16-39                          17
                40-75                            6
                 >75                             1


The feedstocks for these proposed plants are summarized below:

Feedstock                   No. of Plants*    %  Total Capacity

Grains (Corn, Wheat,            34                  83.1
 Barley, Milo)

Sugars (Sugarcane, Sweet         3                   8.2
 Sorghum, Sugar Beets,
 Molasses, Sweet Pota-
 toes, Cheese Whey)

Potatoes                       .2                   0.4

Unknown                          5                   8.3


*Note:  Some  facilities plan to use more than one type of
        feedstock.
                               22

-------
                            Table  2-4

            ETHANOL-FOR-FUEL PLANTS UNDER  CONSTRUCTION
                         (September 1985)*
 State
Company
   Capacity
(Thous.  gal/yr)
Feedstock
Alaska
California
Iowa
Illinois

Indiana
Louisiana
Minnesota
N. Dakota
New Mexico
S. Carolina
Tennessee
Virginia

Diamond R
United Energy (Barrego)
United Energy (Yermo)
Archer Daniels Midland
Archer Daniels Midland
Agmont , Inc .
Solar Alcohol Energy, Inc.
Mississippi River Alcohol
Co.
Minnesota Dairy Tech.
Alchem Limited
Aurora Rresources, Inc.
Agripin
Tennol Energy Company
Newport News Energy Assn.
American Fuel Trading Co.
1,200
1,500
1,500
70,000
50,000
2,500
1,000
42,000
2,300
4,500
2,000
9,000
25,000
1,650
6,000
Barley
Corn,
Corn, molasses
Corn
Corn
Corn, wheat
Corn
Corn
Cheese whey
Barley, potato
Milo
Corn
Corn, Milo
Corn, Barley,
Milo
Hydrous
                                                     Ethanol
*Reference (37)
                                23

-------
                         Table 2-5

                      PROPOSED PLANTS
                          (1981)
                           Ethanol
Code No.    Location      Production       Feedstock

D01
DO 2
D03
DO 4
DOS
D06
D07
DOS
D09
D10
Dll
D12
D13
D14
D15
D16
D17
D18
D19

IA
PA
IN
VA
LA
LA
IN
CO
ME
TN
TX
MI
MI
PA
SC
IN
IA
IA
LA
(gal/yr x 106)
216
63
50
50
40
40
36
30
25
25
22
20
20
20
20
20
20
20
20

Corn
Corn
Corn
Corn
Corn, Molasses
Sugar
Corn
Unknown
Corn
Corn
Milo
Corn
Corn
Corn
Corn
Grain
Corn
Corn
Sugar Cane,
                                          Sorghum,  Corn
                                          Molasses
  D20           SC              20           Unknown


                            24

-------
                      Table 2-5 (Continued)

                        PROPOSED PLANTS
                            (1981)

                          Ethanol
Code No.    Location     Production           Feedstock
(gal/yr x 10°)
D21
D22
D23
D24
D25
D26
D27
D28
D29
D30
D31
D32
D33
D34
D35
D36
D37
D38
D39
D40
D41
D42

KS
MD
MN
NB
IL
KS
MT
IL
IL
KY
WA
MI
VA
MO
IA
ID
FL
MN
GA
CO
GA
NB

18
15
15
15
14.3
12.5
10.5
10.5.
10.5
10
10
10
10
10
10
5
5
4
2.5
2.5
2
1
25
Corn, Milo
Corn
Grain
Grain
Corn
Corn
Unknown
Unknown
Unknown
Corn
Corn
Corn
Grain
Corn
Corn
Wheat, Barley, Pota
toes
Corn, Milo
Barley, Wheat
Corn
Potatoes, Barley
Grain
Corn


-------
 2.2.6   PROPOSED  PLANTS  (1985)

 In  1985 there  were  38 proposed  ethanol-for-fuel  plants  in  the
 U.S. (37)  These  38 plants  represent  a  capacity  of  nearly  2.2
 billion liters per  year  (593 million  gallons  per year).
 Approximately  one quarter of these  plants  are expected  to  enter
 construction.  The  proposed plants  (1985)  are listed  by state  in
 Table 2-6.

 Another 36 ethanol-for-fuel projects  are "on  hold."   These 36
 plants  represent  over 1.9 billion liters per  year (508  million
 gallons per year) production.  (37)  The probability of  any of
 these facilities  reaching construction  is  very low. (37)

 2.2.7   PROJECTED  PRODUCTION

 A study conducted by the Department of  Energy in 1979 estimated
 the availability of surplus agricultural feedstocks and  biomass
 sources for conversion to ethanol.  Based  on  this information,
 the maximum amount  of ethanol which can be produced from these
 sources is presented in Table 2-7.  To  calculate these  projec-
 tions,  the DOE study assumed the following percentages .of  feed-
 stocks  to be available for  conversion to ethanol:  cheese  whey,
 80 percent; citrus  wastes,  80 percent;  corn,  80  percent; wheat,
 80 percent; sugar cane, 100 percent; and sweet sorghum,  100 per-
 cent.  The study also considered sweet  sorghum to be a better
 feedstock than corn because it  is cheaper, has a higher  yield,
 and requires less feedstock processing.  Therefore, this study
 assumed that 14 million acres of pastural  or  set-aside  land
 would be converted to sweet sorghum production by the year 2000,
 allowing the elimination'of corn as a feedstock.  In addition,
 it should be noted that the projections for wood  and agricul-
 cultural residues depend on the development of appropriate
 technology.

 Geographic Distribution

 Figure 2-1 presents the geographic distribution  by EPA regions
 of existing ethanol-for-fuel plants which were existing  in 1981
or were under construction and proposed for construction.  As
 this figure shows, Regions  4, 5, 6, and 7 were projected to
 contain 73 percent of the facilities and 83 percent of the total
 capacity.

 Figure 2-2 shows the same projected plants by  state.
 Thirty-three states were projected to have at  least one
ethanol-for-fuel facility.  Six states  including Colorado,  Iowa,
 Illinois,  Indiana, Louisiana, and Kentucky were projected  to
have five  or more facilities.  Table 2-8 shows the 1985 status
by state,  showing the number of existing plants and the number
of operating plants.


                               26

-------
           Table 2-6

ETHANOL-FOR-FUEL PLANTS PROPOSED
        (September 1985)
                   Capacity
State
Alabama
Florida
Iowa



Illinois

Kansas
Kentucky
Louisiana






Maine
Minnesota




Montana

North Carolina
Nebraska




Location
Decatur
Pensacola
Ames
Eddyville
Ethersville
Spencer
Argo
Piatt County
Liberal
Calvert City
Baton Rouge
Jonesville

New Iberia

New Orleans
Vidalia
Auburn
Appleton
Clarkf ield
Glenville
Mankato
Marshall
Billings
Hardin
Lumberton
Benkleman
Blair
Lincoln
Sidney
Winnebago
(Thous. gal/
25,000
3,000
23,000
6,000
6,000
10,000
135,000
6,500
6,000
20,000
10,000
5,000

49,000

35,000
12,000
15,000
3,150
5,000
10,000
20,000
10,000
4,000
10,000
1,500
30,000
16,500
12,000
18,000
10,000
yr) FeedstocK
Corn
Milo
Corn
Corn
Corn
Corn
Corn
Corn, Milo
Corn
Corn
Corn
Molasses,
Sugar
Sugar cane,
Sorghum
Corn
Corn
Corn
Corn
Corn
Corn
Corn
Corn
Wheat
Barley
Corn
Corn, Milo
Corn
Corn
Wheat
Corn
               27

-------
                      Table 2-6 (Continued)

                 ETHANOL-FOR-FUEL PLANTS PROPOSED
                         (September 1985)
 State
   Location
  Capacity
(Thous. gal/yr)
  Feedstock
New Jersey

New Mexico


Oregon

Texas

Utah

Virginia
Carney's Point

Las Cruces
Lovington

Klaraath

Hereford

Salt Lake City

Norfolk
Stony Creek
Taskey
   10,000

   10,000
   12,000

   10,000

    7,000

    2,000

   10,000
   10,000
    5,000
Corn

Corn, Milo
Milo, Wheat

Corn

Corn

Wheat

Corn, Milo
Corn
                                28

-------
                             Table 2-7

               PROJECTED MAXIMUM ETHANOL PRODUCTION
                   FROM U.S. BIOMASS RESOURCES
                    [Million Gallons Per Year]

Wood
Agricultural Residues
Grains:
Corn
Wheat
Grain Sorghum
Total Grains
Sugars :
Cane
Sweet Sorghum
1985
21,800
10,300
2,100
1,400
300
3,800
200
200
1990
20,200
11,300
900
1,600
300
2,800
700
3,000
2000
25,800
13,100
2,000
300
2,300
700
8,300
Cane
Sweet Sorghum
Total Sugars
Municipal Solid Waste
Food Processing Wastes:
Citrus
Cheese
All Other
200
200
400
2,300
200
100
300
700
3,000
3,700
2,500
300
100
300
700
8,300
. 9,000
2,900
400
200
300
Total Processing Wastes
   600
   700
   900
TOTAL
39,200
41,200
54,000
Reference 3.
                                29

-------
                           CO
             o e
             >. ».
            on
                          fa

                          A
                          II
                        rH 0PM


                        ^g"
                          MCO
                        « H •
                        >-i fci O
                        3 «
                        toO l—l >-i
                        fa
                          COO
                          0
O
O
Ed
O

O
W
H
O
W
30

-------
    W

    En
    g
    i
i   Hen

-------
                            Table 2-8

                ETHANOL-FOR-FUEL PLANTS BY STATE
                        (September 1985)
                                    Number of Plants
State
Alabama
Arkansas
California
Colorado
Florida
Georgia
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana i
Maryland
Michigan
Minnesota
Montana
North Dakota
Nebraska
New Jersey
New Mexico
Ohio
Oklahoma
Pennsylvania
South Dakota
Tennessee
Texas
Utah
Virginia
Washington
Wisconsin
Total
1
1
6
5
2
2
3
6
2
9
3
4
6
1
2
5
2
1
4
1
7
2
1
2
2
1
3
2
9
3
4
Operatina
n
\j
i
j.

0

i
J.
1
X
5
o
t*
i
J.
4
*±
0
•3
J
9
<<£
1
J.
9
£*
1
•3
O
•J
£,
1
X
1
X
0
1
J.
I
-L
1
J.
T
J.
2
   TOTAL

Source:  (37)
102
                     57
                                 32

-------
Future Ethanol-for-Fuel Processes

In addition to the feedstocks in use in the ethanol- for-fuel
industry, it is projected that sugar cane, sweet sorghum, sugar
beets, cane molasses, citrus molasses, cellulose, cheese whey,
and potatoes may be used to provide ethanol for fuel.  Despite
the feedstock used, all new ethanol-for-fuel plants constructed
in the near future are expected to use fermentation, distilla-
ation, and dehydration systems similar to those for existing
ethanol-for-fuel plants.  This is due to the fact that all
feedstocks enter the fermenter as simple sugars regardless of
their original form.  Nonfermentable matter (e.g., protein,
fiber, lignin) is routed to by-product processing, thus provid-
ing an ethanol/water feed to distillation and dehydration which
is independent of the feedstock.

Feedstock preparation techniques, on the other hand, will vary
depending on the type of biomass used for conversion.  Over the
years, various methods of grinding, pulverizing, and mashing
have been specially developed for different feedstocks.  Also,
by-product recovery systems, although analogous, will vary
according to the desired form (i.e., dry, moist, or liquid) and
marketability of the recovered by-product.

2.3  BTHANOL-FOR-FUEL PROCESS DESCRIPTION

In the United States, ethanol for beverage  purposes must be
derived  entirely from the fermentation of starch or sugar feed-
stocks.   However,  industrial- or  fuel-grade ethanol can  be made
via fermentation or synthesized from ethylene, a gas derived
from  petroleum.  Synthetic  ethanol  is not considered  in  this
document. Only those facilities producing ethanol which  is
derived  from  renewable  biomass  feedstocks are  defined  as part of
this  industry.

All fermentation ethanol plants employ  four basic processes:
feedstock preparation,  fermentation,  distillation,  and  dehydra-
tion.  A fifth process,  by-product  recovery,  is  also  possible,
but not  necessarily  included in all ethanol-for-fuel  plants.
Slight variations  within each of  the  first  four  processes  are
available;  however,  differences in  fermentation,  distillation,
and dehydration  do not  result  in  significant  changes  in the
quality  or  amount  of  emissions  and  effluents.   Those  steps  which
may affect  the  characteristics  of the  wastes  generated  include
 the  feedstock preparation  technique and the inclusion of the
 fifth process,  by-product  recovery.

 2.3.1  FEEDSTOCK PREPARATION

 Feedstock preparation includes  all  steps in converting the  raw
 material (i.e., corn or wood chips) to a saccharified mash which
 enters the  fermenters.   Depending on the feedstock, different
                                33

-------
 methods of preparing a saccharified mash and for removing valu-
 able by-products from the feedstocks, such as germ (protein) or
 lignin (cellulosic material), are available.  The feedstock
 preparation techniques in use in the existing ethanol-for-fuel
 industry include dry milling, wet milling, wood sugar
 preparation,  and cheese whey preparation.

 Processing of Grain Feedstocks

 The  incoming  grain contains considerable amounts of dirt and
 extraneous matter such as stover, cobs,  twigs,  sand,  tramp
 metal,  mold clumps, and stones.   Therefore,  the grain is first
 cleaned and rough ground to remove the foreign  matter.   Large
 amounts of particulate emissions occur from  grain receiving,
 cleaning,  and conveying in addition to storage, milling, and
 processing of the grain.   The majority of the emissions  are
 fugitive and  arise primarily from raw material  handling.  After
 preliminary cleaning and  grinding, two methods  are  available for
 preparing  the grain for fermentation: dry milling  and wet
 milling.

 Dry  Milling.   In the dry  milling process,  the grain is bar
 milled  or  hammer milled to form  a fine meal.  Milling breaks the
 outer cellulosic wall around each kernel  to  expose  more  starch
 surface to the action of  cooking and conversion.

 Water  is added to the milled grain and the suspension is fed
 into a  cooker.   Cooking may be carried out under  pressurized or
 atmospheric conditions in either batch or continuous  processes.
 Steam is injected  during  cooking to  raise  the temperature  which
 aids in solubilizing and  gelatinizing the  mash,  thus  forming a
more suitable  substrate for enzymatic hydrolysis  (biological
 breakdown)  of  starches into sugars.

After cooking,  the mash is  cooled to about 63°C and ground
barley  malt or  fungal  amylase  is  added to  convert the
 solubilized starches by enzyme action into component  five  and
six carbon  sugars.   This  conversion  may take  place  in a  separate
vessel  called  a  "converter"  in order to free  the  cooker  for  the
next batch.  The slurry,  at  this  point called "mash," is further
cooled  via  vacuum  or tubular heat  exchangers  to about 27°C and
then pumped to the  fermenters.

Wastes  from the mashing process  consist of condensate from pres-
sure cookers and vacuum coolers  in addition to residual material
from vessel cleanup.   For plants operating in this mode,  the
load comprises about  12 percent  of the total  plant waste.  For
plants with atmospheric cookers and  shell and tube mash coolers,
the load would be  lower.                                 =-.

Wet Milling.  Another method of grain preparation used for corn
is referred to as wet milling.   in this process, the corn  is

                               34

-------
first steeped in a dilute aqueous solution of sulfur dioxide to
soften the kernels and cob (if whole corn is used) and to remove
soluble materials.  The sulfur dioxide extract is collected and
concentrated to produce a product which is sold for fermentation
media and animal feed.

The softened kernels are then coarse-milled to loosen the oil-
containing germ, then washed and dried.  After drying, the germ
is further processed by solvent extraction to yield the
desirable corn oil and a residual cake which is a valuable
animal feed material.  The material remaining after removal of
the germ passes through successive milling, screening, and
washing to remove the hull fiber, which is dried and also used
in animal feed formulations.

At this point, a slurry which consists of a mixture of starch
and protein remains.  This mixture is separated centrifugally to
produce the protein fraction that constitutes a valuable, high-
protein corn gluten by-product.  The remaining fraction, which
is starch, is obtained from the centrifuges as a concentrated
slurry containing upwards of 40 percent solids.

The starch stream is then fed into a converter for enzymatic or
acid hydrolysis to fermentable sugars.  Vacuum or tubular heat
exchangers may be used to cool the saccharified mash before
entering the fermenters.

The wastes generated from the corn wet milling process include
the water removed from the sulfur dioxide extract during concen-
tration, the numerous wash waters, and the condensate from the
vacuum coolers if this equipment is used.

In cases where corn wet milling is used in conjunction with
another process (e.g., corn sweetener), the wastes generated
from corn wet milling were not considered in ethanol-for-fuel
industry since corn wet milling will be covered as part of the
food industry.

Wood Sugar Preparation

It is possible to produce fermentable sugars from wood by treat-
ing it with sulfuric acid, lime rock, and caustic soda.  This
process is one form of pulping in which the resulting fibrous
cellulosic material can be separated from a solution of calcium
lignosulfate and wood sugars by filtration or centrifugation.

The lignin/sugar solution is referred to as spent sulfite liquor
(SSL) and is usually concentrated in evaporators prior to
further processing.  Nearly all pulp mills that employ this
technique either burn or recover the lignin from the SSL;
however, one pulp mill routes this SSL stream to an ethanol


                               35

-------
 plant which removes the sugars (via fermentation) before
 recovering the lignin.

 The SSL stream is steam stripped to remove volatile sulfur com-
 pounds and cooled using noncontact heat exchangers.  The stream
 is then neutralized to a pH of 4.3 and supplemented with aqueous
 ammonia to satisfy the nutritional requirements of the yeast
 prior to fermentation.

 Excluding the wastes generated from pulping operations, the
 wastes generated from this process include the evaporator
 condensate and the overhead stripper condensate containing the
 soluble sulfur compounds.

 Cheese Whey Preparation

 Cheese whey is currently being used at one plant  to produce
 96.5 percent ethanol.   The ethanol is  sold to another plant
 which dehydrates the ethanol for its eventual use as a fuel.
 The use of cheese whey as a feedstock  has significantly reduced
 the environmental impact of discharging cheese whey to the local
 receiving water or wastewater treatment plant (4).

 The preparation of cheese whey for use in ethanol production is
 shown in Figure 2-3.   The whey concentrate as received con-
 tains 35 to 40 percent total solids and a lactose content of 35
 to 38 percent (5).  After pasteurization, the cheese whey enters
.a  solid bowl centrifuge which removes  the whey protein.  The
 whey protein is a valuable by-product  used in food  additives
 such as casein.   The supernatant,  a 75 percent lactose stream,
 enters the fermenters.

 The necessity of maintaining high-purity surroundings for food
 additive processing  requires numerous  system  cleanings.  This  is
 the only waste stream  generated by this process.

 2.3.2  FERMENTATION

 The biological conversion of the saccharified mash  by yeast for
 the production of  ethanol  can be rendered in  a continuous  or
 batch fermentation process.   The grain and wood sugars are  con-
 verted  into  ethanol and  carbon dioxide according  to  the
 following  chemical equation:
          C6H1206 - - **2C2H50H  +  2CC>2
                      yeast

Other reactions also occur producing  small quantities of acetic
acid, aldehydes, and longer chain alcohols often referred  to as
fusel oils.  These processes are well documented in most
biochemistry text books.
                               36

-------
a
a
v   e
n   o
     C
     0)
O   !-"
     3.
                                    13 y

                                    C 
-------
 Continuous and batch fermentation processes require temperature
 control,  agitation,  and pH adjustment.   Fermentation is an exo-
 thermic process,  and external or internal 'cooling is usually
 employed  for temperature control.  Related  to this is the neces-
 sity to agitate the  fermenting mash to  maintain homogenous
 temperature  and ethanol concentration gradients throughout the
 vessel.  To  retard bacterial growth during  fermentation, the pH
 is  controlled between 4.5 and 5.0;  strains  of yeast used have
 been developed to tolerate these acidic conditions.

 Depending on the  choice of fermentation process (batch or con-
 tinuous),  the fermented mash will vary  with respect to yeast
 reclamation  and recycle, fermentation vessel residence time,
 live yeast concentration,  and ethanol concentration.   These four
 parameters are closely interrelated and require special atten-
 tion for  the maintenance of  steady-state operation in continuous
 fermentation.

 Batch Fermentation.   Batch processes add predetermined amounts
 of  pure cultured  yeast to  each reactor  vessel containing the
 saccharified mash.   The residence time  of the mash varies from
 60  to 72  hours, resulting  in a final ethanol concentration of
 approximately  10  percent by  volume.   The yeast may be removed by
 centrifugation  and sold as a protein by-product.   The relative
 ease of batch  fermentation has led  to its widespread  use in the
 beverage and ethanol-for-fuel  industries.

 Water  usage  in  batch  fermentation is limited to noncontact cool-
 ing  in the fermenters.   The  only  source of  wastewater is from
 fermenter  washing.  The  fermenters are  washed  after each batch
 with steam and  disinfectants to maintain sterile  conditions.

 Large  quantities  of carbon dioxide are  produced during  fermenta-
 tion which contain small amounts  of  water vapor along with
 traces  of  volatile organic compounds.   Besides  ethanol,  these
 organic compounds include acetaldehyde  and  furfural which  are
 by-products of  the saccharification  and fermentation  reactions.

 Continuous Fermentation.   In  continuous fermentation,  the  yeast
 is separated from the  fermented mash  and recycled  to  the  fermen-
 ters.   A portion of the  recycle yeast stream  is discharged  or
 recovered as a by-product to remove  dead yeast  and to prevent
 contaminants from building up  in  the  system.  Although
concentrations of 10 to  12 percent ethanol are  achievable,  this
 level of ethanol  is toxic to yeast;  therefore,  the ethanol
concentration is generally kept below six percent  to maintain  a
high yeast population.  The  retention time for  continuous
fermentation is much shorter than batch fermentation, usually
between eight and twenty-four hours.  in addition, the yeast
population density is greater in a continuous process to enhance
the  conversion of sugar to ethanol.
                               38

-------
Only two ethanol facilities in the United States currently use
continuous fermentation; these plants also provide anhydrous
ethanol for fuel.  Plant A01 uses both batch fermenters and
continuous fermenters.  Plant AO7 conducts a type of continuous
fermentation in which a series of well-mixed reaction vessels
are used with a total retention time of eight to ten hours.

As in batch fermentation, continuous fermentation produces large
quantities of carbon dioxide containing traces of organic com-
pounds and water usage in continuous fermentation is restricted
to noncontact cooling water.  Unlike batch fermentation,
continuous fermenters are cleaned infrequently; this results in
a reduction of wastewater.

In both fermentation processes, the fermented mash, known as
"beer," is sent into a beer well en route to the beer still.
The beer well is a holding tank for the fermenters which ensures
continuous feed to the beer still and allows some settling of
solids out of the mash.

2.3.3  DISTILLATION

In distillation, the solids and most of the water is separated
from the ethanol.  The process variations which occur at this
point are no longer a function of the feedstock but of the ulti-
mate product quality desired and age of the plant.  For example,
those plants which produce potable ethanol as well as fuel-grade
ethanol include additional.purification steps in their distilla-
tion trains to remove nearly all impurities (e.g., fusel oils
and aldehydes).  This type of distillation sequence is referred
to as a conventional system.  A second type of distillation
train is used by former beverage alcohol producers who have
converted their facilities to produce only ethanol-for-fuel.   In
these converted facilities, purification columns are eliminated
in response to relaxed purity requirements for fuel blends.
Finally, a third distillation scenario is depicted by grassroots
ethanol-for-fuel facilities that are designed to minimize energy
requirements and wastewater generation.

Conventional Distillation

Prior to entering the beer still, the fermented mash may enter a
degasser 'drum where the dissolved carbon dioxide is flashed  off.
The amount of carbon dioxide released here is comparatively
small and is not recovered.  The fermented mash, containing  10
to 12 percent ethanol, is  then preheated by the beer still
overhead heat exchanger before entering the column.  Once the
mash enters the beer still, the solids and much of the water are
separated from the ethanol.

Live steam  is  injected at  the base of the column to strip the
ethanol from the fermented mash introduced near the top of the

                               39

-------
 still.   The vapor leaving the top of the still is condensed and
 forms the  product,  an 80 percent ethanol solution containing
 some  impurities.   The discharge from the base of the column
 contains the soluble and suspended substances carried through
 the process. Depending on the feedstock and its preparation
 technique,  the  beer still bottom stream may contain many useful
 by-products.

 The purification  columns following the beer still remove the
 aldehydes,  fusel  oils, and water,  while concentrating the
 ethanol.  Figure  2-4 illustrates a typical column arrangement.

 The overhead beer still stream containing the ethanol enters a
 solvent  extractor which functions  as an extractive distillation
 column.  The water  injected into this column helps to separate
 the fusel oils,  and  aldehydes  from  the ethanol and may be fresh
 or recycled from  another part of the plant.   The water and
 ethanol  exit the  bottom of the column with an ethanol concen-
 tration  of  10 to  20 percent.   The  more volatile aldehydes and
 fusel oils  leave  the column at the top and just below the feed
 tray, respectively.

 The aldehyde stream from the  solvent extractor is sent to the
 aldehyde concentrating column along  with the overhead stream
 from the rectifier,  which is  also  high in aldehydes concentra-
 tion.  The  aldehydes exit the top  of the concentrating column;
 the bottom  stream,  containing some ethanol from the rectifier
 and fusel oils  from  the  solvent  extractor,  is recycled to the
 solvent  extraction  column.

 The fusel oil-rich  stream removed  from the solvent extractor
 enters the  fusel oil column where  they are removed in a  concen-
 trated stream overhead.   The  water which enters the fusel oil
 column leaves the bottom  of the  column and is pumped  to  the
 wastewater  treatment plant.

 The rectifier receives the  dilute  ethanol  stream  (containing
 small quantities of  aldehydes) from  the  solvent extractor.   The
 aldehydes are removed  from  the top and sent  to the aldehyde  con-
 centrating column, while  the  binary  azeotrope  of  five  percent
 water and 95 percent ethanol  is  removed  near  the  top  of  the
 rectifying column.   The ethanol  stream from  the rectifier is
 then routed  to  the dehydration system.   The  rectifier bottoms,
 which is relatively  pure  water,  can  be discharged  to  the
 wastewater  treatment  system or recycled  to the  solvent
 extractor.

Wastewaters from this multi-column process comprise two  to four
 percent of  the  total plant BOD load  and  fifteen to  thirty per-
cent  of  the total wastewater volume, depending on whether or  hot
 the rectifier bottoms  are recycled.  This does  not  include the
wastewater  from beer still bottoms which is routed to by-product

                               40

-------

-------
   JCT
          ril
           J5-S
        * 1
        i.o s
            •
            a
            M
            I
-c*
        s-1
          t,
         * s

                                                  §
                                                  M

                                                  I
                                               
-------
processing.  Concentrated aldehydes may be discharged to the
wastewater treatment system or burned as fuel.  Fusel oils,
which are less volatile than aldehydes, may be combined with the
ethanol product without affecting the performance of fuel
blends.

Vents on overhead condensers used to condense the distillation
column vapors are sources of volatile organic emissions such as
ethanol, aldehydes, and fusel oils (amyl alcohols).  Although
these vent streams may have high concentrations of these com-
pounds, the total volume is very low.

Converted Beverage Plants

A high-purity product is not necessary if ethanol is to be used
for fuel; therefore, distillers who have converted their
beverage alcohol plants can eliminate the solvent extraction
column and the aldehyde concentration column as illustrated in
Figure 2-5. The removal of these columns from the distillation
train reduces the energy required to separate the ethanol from
water and also reduces the amount of wastewater generated.

In this method, the degasser drum and the beer still function in
the same manner as conventional distillation schemes with the
concentrated ethanol product sent overhead and the solids
removed from the bottoms.  Instead of being routed to a solvent
extraction column, the top ethanol-rich stream now enters the
rectifier near the middle of the column.  To prevent the
accumulation of fusel oils within the column, a sidestream rich
in fusel oils is removed from a plate near the top of the
column. The fusel oil sidestream contains ethanol as well as
water which is usually removed in a fusel oil concentrating
column.  The concentrated fusel oils may be blended back into
the final product or used as a source of fuel for the distil-
lation columns.  A 96 percent ethanol stream leaves the top of
the rectifier and is pumped to the dehydration system.  The
rectifier bottoms are pumped to the wastewater treatment plant.

The wastewater generated in this distillation scheme is
estimated to comprise two to four percent of the total BOD plant
load and ten to fifteen percent of the total volume of
wastewater sent to the treatment system.

Current Designs

The widespread use of distillation in the oil industry has led
to technology advances in design techniques which are applicable
to the ethanol-for-fuel industry.  Ethanol plants of the future
will utilize these advances to simplify the necessary separation
processes and reduce energy consumption.
                                42

-------
                                                 to

                                                 I
                                                 O*



                                                 (1)
                                                     3

                                                     W
                                                     O
                                                     W




                                                     H


                                                     W
                                                     o
                                                     u
CO
    43

-------
Figure 2-6  illustrates  the basic  features of  an  ethanol-for-
fuel distillation design which might be  found  in a grassroots
facility.   The system is similar  to the  two-column converted
beverage alcohol plant.  However, the beer still no  longer
receives its heat from  live steam but from a  reboiler.  Also,
the second  column, called a stripping column  in  this case,
receives a  recycled stream from the dehydration  system.

The beer still overhead stream enters the stripping  column con-
taining approximately 50 percent ethanol.  The ethanol/water
azeotrope occurs at a concentration of 95 to  96 percent ethanol.
This stream leaves the top of the column and  is then condensed
and pumped  to the dehydration column.  A sidestream  near the top
of the column enters a separator which removes the fusel oils
and recycles the remaining liquid to the stripping column.  The
remaining input to the stripping column is an ethanol/water
stream from the dehydration system.  Most of  the dehydration
agent which enters the stripping column via the dehydration
recycle stream goes overhead with the ethanol and is sent back
to the dehydration system.

In this distillation scheme, all the wastewater from dehydration
is discharged through the distillation system, resulting in an
increase of less than one percent.  On the other hand, the use
of reboilers in the beer still and rectifier  rather  than live
steam injection results in a 20 percent decrease in wastewater
generation  for this system.

As in conventional distillation, the current distillation train
is a source of small amounts of volatile organic compounds which
are emitted from the vents on column condensers.

2.3.4  DEHYDRATION

When a mixture of ethanol and water is distilled at atmospheric
pressure, a minimum boiling point azeotrope is formed.  It is at
this point  (approximately 96 percent ethanol concentration) that
further separation of ethanol and water is impossible using sim-
ple distillation techniques.  To produce anhydrous ethanol (pure
ethanol), a third compound (dehydration agent) can be added to
the mixture to alter the azeotrope and subsequently permit the
removal of  all the water from the system.  This sequence of
events is referred to as dehydration.

Currently,'  there are two methods for dehydration in the ethanol-
for-fuel industry:  one method consists of a self-contained
add-on unit and is used in beverage alcohol plants that have
been converted to produce anhydrous ethanol; the other is
designed as an integral part of the distillation system and is
used in ethanol-for-fuel facilities.  A variety of dehydration
agents are  available which are suitable for either system,
including benzene, hexane, ethyl ether, and gasoline.

                               44

-------
o
4J
 S ca
•5 M
3

                      l-l
                      O
                      4J

                      2.
                      «
                      a.
                      cu
                          rH
                           0)
                           co
           00
£
           Cfl
                g
                §
§
s
      i     g
      M    -H
      J-l    4J
      CO 8  (8
         O  )-l
      lU H T3
      r-l IW  >»
      O    J3
      >>     
                                            CO
                                            JJ
                                            ca
   •8

   S-g
                              45

-------
 The first system that is discussed uses a distillation column to
 strip out the dehydration agent from the product ethanol stream;
 this method is referred to as the solvent recovery method.  The
 second system allows  a large amount of the dehydration agent to
 remain in the ethanol and is referred to as dehydration without
 solvent recovery.

 Dehydration With Solvent Recovery

 A typical solvent  recovery scheme is shown in Figure 2-7.   The
 solvent currently  used by three ethanol-for-fuel plants is ben-
 zene.   The addition of benzene, both fresh and recycled from the
 benzene recovery column, produces a ternary azeotrope.  In the
 dehydration column, all of the  water and benzene (along with
 some ethanol)  is taken off in the overhead stream.   Ethanol,
 present in excess, is withdrawn from the bottom of  the column.

 The  overheads  from the benzene  dehydration column are cooled in
 a separator and  form  two layers:   a water/ethanol-rich bottom
 layer  containing some residual  benzene and a benzene/ethanol-
 rich top layer containing a small amount of water.   The bottom
 layer  is sent  to the  benzene  recovery column where  all the
 benzene and ethanol are stripped  and recycled to the dehydration
 column.   The  stream from the  benzene recovery column bottom,
 which  is nearly  all water,  is sent to wastewater treatment.   The
 top  layer from the separator  is recirculated to the  benzene
 dehydration column.

 The  only wastewater stream from the dehydration system is  the
 bottom  stream  from the benzene  recovery  system.   This stream is
 very small (less than one percent of the total volume of process
 wastewater),  is  low in BOD and  total suspended solids,  and may
 contain trace  amounts of benzene.

As with distillation  column condensers,  the vents on dehydration
column  condensers are sources of  small amounts of volatile
organics.   Also, the  vent on  the  two-phase separator is  a  source
of volatile organics.   In addition  to  compounds  such as  ethanol
and  fusel oils,  dehydration agents  (e.g.,  benzene) are  also
emitted  from these sources.

 Dehydration Without Solvent Recovery

A flow diagram for a  dehydration  system  that  does not  recover
the  dehydration  agent is  presented  in  Figure  2-8.  One  ethanol-^
for-fuel  plant uses unleaded gasoline  as the  dehydration agent
and, by  leaving  the gasoline  in the  ethanol,  satisfies  the re-
quirements set by the  Bureau of Alcohol, Tobacco, and  Firearms
 (ATF) for denaturation.   This scheme  is more  indicative  of
future trends for the  ethanol-for-fuel industry.
                               46

-------
                  ss-
                  SSI
                  e  o
                  o>  o
              o
              u
              2
              M—
              a
              Bu
              
                  I £ O 01
                 IT) 4J t-1 -H
                 ON U to O
                   47

-------
J.
rH. 3
O 0)
u s
II
4J

2
(8
CU
0)
OT
. B
h O

as
•H M
fe &

  §
  M


  I
              0) 09

              §=1
              Cu O
4J
U
    48

-------
           HH £ ?  l^Vi?88 solvent recovery, the dehydration
  n hhi«   ?       the dehydration column.  Operating conditions
 in this column are only severe enough to remove all of the water
 (along with some gasoline and ethanol) ; a 50/50 blend of ethanol
 and gasoline is withdrawn off the bottom of the column.

 This system also sends the overhead stream from the dehydration
 system to a separator which returns the upper gasoline-rich
 phase to the dehydration column and the lower ethanol/water
 Zu^^u Hhe ^ectifier used in distillation.   Thus,  water leaves
 this dehydration system via the rectifier, and there is no
 wastewater generated from the dehydration system proper.

 Air emissions from this dehydration system are similar to those
 emitted from dehydration systems with solvent recovery.

 2.3.5  BY-PRODUCT PROCESSING

 Depending on the feedstock and the preparation technique used,
 the stillage from the bottom of  the beer still may be  recovered
 as  a marketable,  high-protein by-product.   Several variations
 exist in the method  of recovering  whole  spent stillage.   Basi-
 cally,  all ethanol plants  fall into two  categories:   (1)  those
 with  no  recovery  of  this material,  and (2)  those  utilizing  evap-
 orators  and dryers for complete  recovery.

 In  some  instances, the quantity  of  stillage does  not warrant  the
 capital  expenditure  required  for by-product recovery.   This is
 particularly true if feedstocks  other  than  grain  are used which
 are deficient in  protein content (e.g.,  sugars, cellulose).   it
 is  more  economical for these  plants  to dispose of  wet  stillaqe
 to  nearby  farmers  for cattle  feed than to install  a recovery
 system.   Those plants that do  not recover stillage have  a
 substantially different wasteload since  the by-product  recovery
 system is  the major  contributor  to  total distillery waste.

 Figure 2-9  illustrates  a typical process for  a by-product
 recovery system.  Whole spent  stillage is approximately five  to
 seven percent solids;  thus, by-product recovery is essentially  a
 dewatering process.   The first step consists of passing the
 whole stillage over  a  screen. , The coarser  solids  are retained
 and sent to a press  for further removal of  soluble solids.  The
 press cake,  if dried  separately on driers,  becomes "distillers
 light grain."  The thin stillage liquid is normally centrifuaed
 to remove suspended  solids, then piped to multiple effect -
 evaporators where it  is concentrated to a syrup containing about
 ^b to 50 percent solids.  These evaporated  solubles may be
thermally dried to produce "distillers dried solubles," or more
commonly dried with press cake in rotary driers to produce
 "distillers dark grains."

-------
                                                                         I
                 Whole Stillagc
                             By-P roduct    Exhaust
 Dried Grain
With Solubles
   T
W»stewater
 Effluent
                Figure 2-9

           PROCESS FLOW DIAGRAM:
             BY-PRODUCT RECOVERY
                       50

-------
One ethanol-for-fuel plant  uses  a  cellulose  based  feedstock.   in
this case, the lignin  is recovered and concentrated  as  it  too  is
a valuable by-product.  Evaporation  lowers the moisture content
to approximately 50 percent before the lignin solution  is  pumped
to its own processing  plant.

The 'high yeast concentration required in  continuous  fermentation
and the necessary separation of  the  yeast from the lignin/
ethanol solution before entering the beer still produces a
second by-product stream, dried yeast.  After the last  fermen-
tation vessel in the continuous  fermentation train,  centrifuges
are used to remove the yeast.  A portion of the yeast is recy-
cled to the first reactor and the rest is pasteurized to kill
the yeast which can then be disposed of or sold as a by-product.

The major contribution to the ethanol-for-fuel plant wasteload
is from the by-product recovery  system.   It can account for as
much as 80 percent of the total plant waste.  The most  signifi-
cant source of wastewater within the feed recovery system  is the
condensate from evaporators.  Although most plants discard their
condensate, at least one grassroots  plant recycles up to 95 per-
cent of the condensate to the mashing tank.  This practice is
indicative of the new plants that will be coming on-line.
Finally, dust emanating from grain dryers may constitute another
source of wastewater if wet scrubbers are used.  Many plants
eliminate this water through the use of cyclones and combine the
collected dust with by-product grains.
                               51

-------
                            SECTION 3

                  WASTE STREAM CHARACTERIZATION
3.1  DATA COLLECTION

An extensive literature search revealed that a limited amount of
information existed in the literature regarding water use and
wastewater quality for ethanol-for-fuel facilities. Consequently,
the Agency devised an extensive sampling program to characterize
the effluent streams from all ethanol-for-fuel plants and several
beverage alcohol plants.  This program supplemented the data
provided by two other studies:  an environmental characterization
of an ethanol-for-fuel facility sponsored by the Industrial
Environmental Research Laboratory in Cincinnati/ Ohio (lERL-Ci),
and a sampling program conducted by the Region IV  EPA Surveil-
lance and Analysis Division (6) concerning effluents from three
rum distilleries.

In addition to these sampling programs, multimedia industry ques-
tionnaires were prepared and submitted under authority of Section
308 of the Clean Water Act, Sections 111 and 114 of the Clean Air
Act, and Section 3007 of the Resource Conservation and Recovery
Act of 1976.  Also, National Pollutant Discharge Elimination Sys-
tem (NPDES) permit applications for ethanol plants were reviewed,
and EPA regional offices were contacted for pertinent effluent
data.  The information gathered from these data collection
activities and sampling programs are summarized in Table 3-1.
This table also specifies whether the data were used in the
pollutant parameter treatability assessment.

3.1.1  MULTIMEDIA  INDUSTRY QUESTIONNAIRE

A multimedia questionnaire was prepared and submitted to ethanol-
for-fuel and beverage alcohol facilities.  This questionnaire
solicited information concerning water use; generation and con-
trol technology for wastewater, air emissions and  solid wastes;
process configuration;  internal stream routing; and chemical
application rates.  Initially, the questionnaires  were sent to
the eight ethanol  plants scheduled for sampling and analysis.
Responses were obtained from plants A01, A03, A06, A07, A10, E02,
and EOS.  A preliminary analysis of these  responses demonstrated
a lack of data on  the efficiency of the control and treatment
systems employed.  Therefore,  the questionnaires were revised  to
obtain daily monitoring data on untreated  and treated waste
streams and sent  to six beverage alcohol plants.   Responses were
obtained from plants E04,  EOS, El2, El3, El7, and  El8.

                                52

-------
                            Table  3-1



            ETHANOL-FOR-FUEL DATA BASE SUMMARY
-Plant
Code
A01
A02
A03
A04
A05
A06
A07
A08
A10
BOX
E02
B03
•04
BOS
E06
B07
B08
B09
Ell
B12
B13
B14
BIS
E16
B17
El 8
819
B20
Type of Analytical Data
3 days, untreated effluent (C, N, P)
No data available
2 years, untreated and treated effluent
(C, N. P)
No data available
No data available
3 days, untreated effluent (C, N, P)
3 days, untreated and treated effluent
(C, N, P)
No data available
3 days, untreated effluent (C, N, P)
S days, untreated effluent (C, N, P)
3 days, untreated and treated effluent
(C, N, P) ,
5 days, untreated effluent (C, N, P)
Average diluted untreated effluent (C)
1 year, treated effluent, avg. untreated
effluent (C)
1 day, untreated and treated effluent;
treatability data
1 year, Monthly average (C)
6 days, untreated and treated effluent
(C, N, P)
3 days, untreated effluent (C, N, P)
1 year, average untreated and treated
effluent (C)
1 year, average untreated and treated
effluent (C)
1 year, treated effluent and treatabil-
ity data (C)
1 year, diluted treated effluent (C)
6 smiths, untreated and treated effluent (C)
1 year, diluted effluent only (C)
1 year, untreated and treated effluent (C)
2 aonths, untreated and treated effluent (C)
1 year, average untreated and treated
effluent (C)
5 days, untreated effluent (C, N, P)
Pollutant
Parameter
Treatabilitv
NO
Mo
Yes
No
No
No
No
No
NO
NO
Yes
No
No
Yes
Yes
Yes
Yes
No
Yes '
Yes
Yes
No
Yes
No
Yes
Yes
NO
No
C • Conventional Pollutant Data

N • Npneonventional Pollutant Data
P • Priority Pollutant Data
                         53

-------
3.1.2  NPDES PERMIT DATA

After the results from the sampling programs and questionnaire
responses were received, EPA regional offices were contacted to
obtain NPDES permit information on ethanol plants regarding
wastewater treatment systems and effluent monitoring data.
Information received from 14 direct dischargers including Plants
A03, E02f E05, E06, E07r E08f Ell, E12, E13, El5f E16, E17, E18,
and E19.

3.1.3  EPA REGION IV SURVEILLANCE AND ANALYSIS DIVISION  (SAD)
       PROGRAM

In 1978, the EPA initiated a study aimed at assessing the options
for disposal of rum distillery wastes and associated environmen-
tal consequences.  Region IV EPA/SAD conducted sampling  and
analyses at plants E01, E03, and E20 for five consecutive days.
Composite samples were taken of the undiluted beer still slops or
raosto stream and of the combined untreated effluent, where pos-
sible.  Single grab samples were collected from each facility s
raw process water, fermentation tank, aldehyde column, and
rectifying column; flow rates of the waste streams were  also
determined  (6,7).

A statistical  and  engineering analysis  demonstrated  that the
effluent quality of the rum distilleries varied significantly
from  the effluent  of  other beverage  alcohol  plants  (as well as
from  ethanol-for-fuel  facilities).  Furthermore, the  industry
orofile  reveals  that  there are  no  rum distilleries providing  or
planning to provide ethanol-for-fuel.   Thus,  the  effluent data
from  the rum  industry were; not  presented  in  this  evaluation,
however, the  data  have been  included in Appendix  E.

3.1.4  lERL-Ci SOURCE TEST EVALUATION

in  anticipation of the rapidly  developing  et1?3^:^:^  *n".
dustry and subsequent environmental impact,  in 1978  the  IERL ci
sponsored  a test program as  part  of its efforts  to  determine
 sampling and  analytical requirements for  ethanol  facilities.
This  program included the monitoring of air  emissions and sam-
 plinq of solid wastes and wastewater effluents.   Information con-
 cerning the streams tested,  sampling frequency,  and analytical
 parameters examined can be found in the EPA report entitled,
 "Source Test and Evaluation Report:  Alcohol Facility for Gasohol
 Production" (8).

 3.1.5  EPA MULTIMEDIA SAMPLING PROGRAM

 In 1980, the Effluent Guidelines Division (EGD),  the Office of
 Solid Waste (OSW), and the Office of Air Quality Planning and
 Standards (OAQPS) of the EPA sponsored a program to characterize
 effluents, solid wastes, and air emissions from ethanol-for-fuel
                                   54

-------
and beverage alcohol facilities.  This multimedia program was
undertaken to provide the Agency with a basis for evaluating
regulatory aspects of wastewater,.solid wastes, and air emissions
from the ethanol-for-fuel industry;

Facility Selection

At the inception of the EPA multimedia sampling program, there
were only five ethanol plants producing ethanol-for-fuel; all of
these plants were selected for sampling.  Data were also sought
from the beverage alcohol industry which was hypothesized to be
analogous to the ethanol-for-fuel industry in terms of the
quality and volume of wastewater generated.  Three plants (E02,
EOS, and E09) were chosen from the beverage alcohol industry for
sampling and analysis.  Statistical data evaluation showed the
effluent from beverage alcohol plants to be similar to effluent
from ethanol-for-fuel plants and justified the combination of the
effluent data from all ethanol facilities tested.

According to the industry profile, approximately 95 percent of
the ethanol-for-fuel plants constructed in the next five to ten
years were projected to use grain feedstocks.  Therefore, plants
EOS and E09  (typical grain distilleries) were selected for test-
ting.  Plant EOS treats its wastewater using aerated lagoons,
rotating biological contactors, and stabilization ponds while
plant E09 discharges its wastewaters to a municipal treatment
system.

Plant E02, which uses the second most common type of feedstock
(sugar cane and citrus molasses), was selected for comparison to
grain feedstock beverage alcohol plants and the rum facilities.
This facility produces products which range from 50 to 95 percent
ethanol.  Its wastewater treatment system  includes aeration
tanks, a clarifier, a polishing pond, and a sludge digester.

Wastewater Sampling

The combined raw wastewaters, treated effluent streams, and
several component raw wastewater sources were tested for con-
ventional and priority pollutants, as well as selected noncon-
ventional pollutant parameters  and those pollutants listed in
Appendix C of the 1976 Consent  Decree  (Appendix C compounds).
All parameters  selected  for analysis are listed  in Tables 3-2
through 3-4.  The ethanol facilities, selected streams, and
analytical parameters evaluated in this program  are summarized  in
Table 3-5.

The primary  EPA reference for sampling effluent  streams  is in
"Sampling and Analysis Procedures  for Screening  of Industrial
Effluents for Priority Pollutants," April  1979  (9).  Additional
information  is  found  in  the June  14,  1979  and December  3, 1979
issues of the Federal Register  (10,11).  The sampling procedures


                                  55

-------
                            Table 3-2

                 LIST OF 129 PRIORITY POLLUTANTS
Compound Name

  1.  acenaphthene
  2.  acrolein
  3.  acrylonitrile
  4.  benzene
  5.  benzidene
  6.  carbon tetrachloride (tetrachloromethane)

    Chlorinated benzenes (other than dichlorobenzenes)

  7.  chlorobenzene
  8.  1/2,4-trichlorobenzene
  9.  hexachlorobenzene

    Chlorinated ethanes(including 1r2-dichloroethane,
    1,1/1-trichloroethane and hexachloroethane)

 10.  1,2-dichloroethane
 11.  1,1,1-trichlorethane
 12.  hexachlorethane
 13.  1,1-dichloroethane
 14.  Ir1,2-trichloroethane
 15.  1,1,2,2-tetrachloroethane
 16.  chloroethane

    Chloroalkyl ethers (chloromethyl, chloroethyl and
    mixed ethers)

 17.  bis (chloromethyl)  ether*
 18.  bis (2-chloroethyly)  ether
 19.  2-chloroethyl vinyl ether (mixed)

    Chlorinated naphthalene

 20.  2-chloronaphthalene

    Chlorinated phenols (other than those listed elsewhere?
    includes trichlorophenols and chlorinated cresols)

 21.  2,4,6-trichlorophenol
 22.  parachlorometa cresol
 23.  chloroform (trichloromethane)
 24.  2-chlorophenol
                                56

-------
                     Table 3-2 (Continued)

                LIST OF 129 PRIORITY POLLUTANTS
   Dichlorobenzenes

25.  1,2-dichlorobenzene
26.  1,3-dichlorobenzene
27.  1,4-dichlorobenzene

   Dichlorobenzidine_

28.  3,3'-dichlorobenzidine

   Dichloroethylenes (I/1-dichloroethylene and
   1,2-dichloroethylene)

29.  lr1-dichloroethylene
30.  1,2-trans-dischloroethylene
31.  2,4-dichlorophenol

   Dichloropropane and dichloropropene

32.  1,2-dichloropropane
33.  1,2-dichloropropylene (1,3-dichloropropene)
34.  2,4-dimenthylphenol

   Dinitrotoluene

35.  2,4-dinitrotoluene
36.  2,6,-dinitrotoluene
37.  1,2-diphenylhydrazine
38.  ethylbenzene
39.  fluoranthene

   Haloethers  (other than those  listed elsewhere)

40.  4-chlorophenyl phenyl ether
41.  4-bromophnyl phenyl ether
42.  bis(2-chloroisopropyl) ether
43.  bis(2-chloroethoxy) methane

   Halomethanes  (other  than those  listed elsewhere)

44.  methylene chloride  (dichloromethane)
45.  methyl chloride  (chloromethane)
46.  methyl bromide  (bromomethane)
47.  bromoform (tribromomethane)
48.  dichlorobromomethane
                                57

-------
                     Table 3-2 (Continued)

                LIST OF 129 PRIORITY POLLUTANTS
49.  trichlorofluoromethane*
50.  dichlorodifluoromethane*
51.  chlorodibromomethane
52.  hexachlorobutadiene
53.  hexachlorocyclopentadiene
54.  isophorone
55.  naphthalene
56.  nitrobenzene

   Nitrophenols (including 2,4-dinitrophenol and dinitrocesol)

57.  2-nitrophenol
58.  4-nitrophenol
59.  2,4-dinitrophenol
60.  4,6-dinitro-o-cresol

   Nitrosamines

61.  N-nitrosodiraethylamine
62.  N-nitrosodiphenylamine
63.  N-nitrosodi-n-propylamine
64.  pentachlorophenol
65.  phenol

   Phthalate esters

66.  bis(2-ethylhexyl) phthalate
67.  butyl benzyl phthalate
68.  di-n-butyl phthalate
69.  di-n-octyl phthalate
70.  diethyl phthalate
71.  dimethyl phthalate

   Polynuclear aromatic hydrocarbons

72.  benzo (a)anthracene (1,2-benzanthracene)
73.  benzo (a)pyrene (3,4-benzopyrene)
74.  3,4-benzofluoranthene
75.  benzo(k)fluoranthane (11,12-benzofluoranthene)
76.  chrysene
77.  acenaphthylene
78.  anthracene
79.  benzo(ghi)perylene (I,12-benzoperylene)
80.  fluorene
81.  phenathrene
                              58

-------
                     Table 3-2 (Continued)

                LIST OF 129 PRIORITY POLLUTANTS


82.  dibenzo (a,h)anthracene  (1,2,5,6-dibenzanthracene)
83.  indeno  (1,2,3-cd) pyrene  (2,3,-o-phenylenepyrene)
84.  pyrene
85.  tetrachloroethylene
86.  toluene
87.  trichloroethylene
88.  vinyl chloride  (chloroethylene)

   Pesticides and Metabolites

89.  aldrin
90.  dieldrin
91.  chlordane  (technical mixture and metabolites)

    DDT  and metabolites

92.  4,4'-DDT
93.  4,4'-DDE(p,p'DDX)
94.  4,4'-DDD(p,p'TDE)

    endosulfan  and  metabolites

95.  a-endosulfan-Alpha
96.  b-endosulfan-Beta
97.  endosulfan sulfate

    endrin and  metabolites

98.  endrin
99.  endrin aldehyde

    heptachlor  and  metabolites

100.  heptachlor
101. heptachlor epoxide

    hexachlorocyclohexane (all isomers)

102.  a-BHC-Alpha
103.  b-BHC-Beta
104.  r-BHC (lindane)-Gamma
105.  g-BHC-Delta
                                 59

-------
                       Table 3-2  (Continued)

                  LIST OF 129 PRIORITY POLLUTANTS
     polychlorinated biphenyls (PCB's)
106.
107.
108.
109.
110.
111.
112.
PCB-1242
PCB-1254
PCB-1221
PCB-1232
PCB-1248
PCB-1260
PCB-1016
(Arochlor
(Arochlor
(Arochlor
(Arochlor
(Arochlor
(Arochlor
(Arochlor
1242)
1254)
1221)
1232)
1248)
1260)
1016)
     Metals and Cyanide, and Asbestos

 114.   Antimony (Total)
 115.   Arsenic (Total)
 116.   Asbestos (Fibrous)
 117.   Beryllium (Total)
 118.   Cadmium (Total)
 119.   Chromium (Total)
 120.   Copper  (Total)
 121.   Cyanide (Total)
 122.   Lead (Total)
 123.   Mercury (Total)
 124.   Nickel  (Total)
 125.   Selenium (Total)
 126.   Silver  (Total)
 127.   Thallium (Total)
 128.   Zinc (Total)

    Other

 113.   Toxaphene
 129.   2,3,7,8-tetra chlorodibenzo-p-dioxin  (TCDD)
*Bis (chloromethyl) ether was deleted from this list on
February 4, 1984 (46 FR 10723); trichlorofluoromethane and
dichlorodifluoromethane were deleted on January 8f 1981  (46 FR
2266).  However, testing for the ethanol-for-fuels industry was
performed prior to these deletions, so for the purposes of this
document, the list appears with all the original 129 priority
pollutants.
                                 60

-------
                  Table 3-3
           CONVENTIONAL POLLUTANTS
Biochemical Oxygen Demand (8005)
pH
Oil and Grease
Total Suspended Solids (TSS)
Fecal Coliform
                      61

-------
                  Table 3-4
                          •

     NONCONVENTIONAL POLLUTANTS ANALYZED
Acidity

Alkalinity

Ammonia

Chemical Oxygen Demand  (COD)

Dissolved Oxygen  (DO)

Settleable Solids  (SS)

Temperature

Total Kjeldahl Nitrogen

Total Organic Carbon  (TOG)

Total Phenol (4AAP)

Total Phosphorus

Total Solids (TS)

Total Dissolved Solids  (TDS)

Total Volatile Solids  (TVS)

Aluminum

Barium

Bismuth

Boron
Calcium

Cobalt

Gold

Iron

Lithium

Magnesium

Manganese

Molybdenum

Palladium

Platinum

Sodium

Telurium

Tin

Titanium

Vanadium

Yttrium
                      62

-------
                      Table 3-4 (Continued)



              NONCONVENTIONAL POLLUTANTS1 ANALYZED





          Acetone                             Nitrites



          n-Alkanes                          Styrene



          Biphenyl                           Dimethyl amine



          Chlorine                           Diethyl amine



          Dimethyl ether                     Dibutyl amine



          Diethyl  ether                      Diphenyl amine



          Dibenzofuran                       Camphor



          Diphenyl ether                     Cumene



          Methyl ethyl ketone                 -Terpineol
^Compounds presented in Appendix C of 1976 Consent Decree.
                                63

-------














o
§
P-4
m
I O
en 55
M
0) *1
*""* Pj
"5 3
H W
>4>
41 B
b 41
.3,3
bf"<
•> O
B.
1|
• O
<•«.»<
JS
41 e
C 0

? B
Ig


«
p"4
I
CO
01
b
41
en
41
g.g
S5




o» e
a a
m •>
O O
•SS 1 ii ii-Si^
bu u bb b b b b
» u ^ oca cacscsu
= =
1 i
 0)U
41 B IW41 41 bT
m co B • we o e c ec ID
9 B B— 9 941 O B •
•M O Cu "O Q Uvl O
t) o.u e e t>9 a.4i
tl 0.41^1 41 U O « GU4I
u-To e e b bje o~< o
JbB4i «3 a B n b»
41 O bO O B > 41
en H HCO co9Hco

1 11




**« oTo o) oi oi t) at
41 41 41 41 41 U 41 41
W4«4v4 «4 »4»4«J»J
SO B B « tO ffl tO
O O O O O O O
bUUU U bbbOCJCJtJ
C5 C9 C9 C9
SXS £ SXSS
ill l 1 l l l

CM CM CM CM CM CM CM CM


X X

X ' X







XXXX X XXXXXXX




XXXX X XXXXXXX







« 41 f- X 0)
41 41 Q £ n 41
Q9QO^tfc* 01 JtfOlpNCMO
41T34l6tM 41^U*O GU41
«*B OIU B03B..S
nSCJCiJ-O UHUZZO3
O 01 OJ U 0)H 41 U 4!*bb41tfc<
b a Cw-l be) bXtoB.OIOIBU
g4iawHo> 30ia«x3tbu
o > e h of a > ui ai o
COHUM H 09 9 !H b] CO W <
«O
r- o
e 2




01 01 01
41 41 41
09 01 09
o o o
.D.D.O B'B'E"
o « o o o o
b b b O OCJ
esco . . .

i i i
•a-^-*
CM CM CM


X

X


"




XXX XXX



.
XXX XXX



41
i
1-4
(M
06 *W
Q) *p4 AJ

a o 41 01 o)
a o B 341
b BU ««-< OJ
01 0) 9>M 01
41 -O 41 
-------
                                      „!
 0)

I
•U
 a
 o
o
m
 
w  ««

 X   0) '
                                                                           B   OX

                                                                           g.  "^

                                                                           ^••Sc
                                                                            4J » O
                                                                           BO
                                                                           i t  a
                                                                                                                 i-i  CM a
                                                                                                                            O-D
                                                                                                                            JJ C
                                                                                                                               0
                                                                                                                            a
                                                                                                                          609<->
                                                                                                                          C-D
                                                                                                                          M    X
                                                                                                                          CCM a
           •D  B
         U    Q)
         O B  a
         BOO)

           2B  e.
           0)
         0> Jti  4J
         > a  o

         03
         b a j£
         O 0)  U
         Uf  9
         8 Q.b
         b S  U


         |S  &
                                                                  65

-------
described briefly below and detailed in Appendix C are based on
these three references.

Each effluent water sample consists of a number of blank, grab,
and composite subsamples.  Depending on which parameters are
determined at each site and on the effluent stream composition,
some of these subsamples were not collected.  Additional param-
eters such as pH, temperature, and dissolved oxygen were to be
performed on-site.

For composite samples, compositing time is typically in the range
of 24 hours, with a constant minimum aliquot of 100 ml taken at
intervals of 15 to 30 minutes to give a minimum composite volume
of 5 liters.  Samples were to be composited automatically,
utilizing ISCO Model 1580 Automatic Samplers.

Some of the parameters listed in Table 3-5 were collected as grab
samples.  Grab samples were obtained at the midpoint of the com-
positing period in a turbulent, well-mixed section of the efflu-
uent stream.  Grab sampling was conducted because of potential
rapid change in the parameter of interest (volatile organics,
phenolics, cyanides, etc.) or because of potential contamination
from the sampling operation (asbestos, fecal coliform).

The methodology of stream selection for wastewater sampling
included collecting a 24-hour composite on three consecutive days
for the total raw waste stream from the ethanol plant and any
major sources of wastewater that were accessible.  Also, three
24-hour composite samples were collected of the effluent streams
from wastewater treatment systems to obtain information regarding
treatment system efficiency.   Finally, raw makeup water samples
were collected to determine net discharge concentrations.  The
characteristics of the makeup water did not change over a 24-hour
period; therefore, daily grab samples were obtained for this
stream.

Solid Waste Sampling

For solid waste sampling, all major sources of solid wastes and
by-products were collected for analyses.  In addition, samples of
the feedstocks were collected and tested to determine if the raw
materials might be the source of toxic pollutants or contami-
nants.  Various techniques were used to collect the solid
samples; a description of the sampling procedures used is pro-
vided in Appendix A.

The solid samples, as well as their acetic acid and distilled
water leachates were analyzed for pesticides, metals, and
selected nonconventionals according to procedures outlined  in
RCRA.   The parameters tested and analytical methods used are out-
lined in Appendix B.  The analytical results of the solid waste
testing are presented in Appendix D.  A detailed discussion of

                                66

-------
the solid wastes associated with ethanol production is provided
in Section 3.7.

Gas Phase Sampling

Whenever possible, the methods used to characterize the air emis-
sions from the ethanol plants were EPA-referenced methods.  These
referenced methods are located in the Federal Register, Vol. 42,
No. 160, August 18, 1977 (12).  In situations where an EPA-
referenced method does not exist for a particular parameter, a
proposed method was used.  A detailed description of the sampling
procedures used at each site is given in Appendix A.

All major point sources of air emissions that were accessible
within the plant were examined for flow rates and concentrations
of suspected air pollutants.  The accessibility of a source was
determined by  its location and size, and the logistics of erect-
ing scaffolding, if necessary.  Fugitive emissions (unintentional
discharges or  leaks of volatile organic compounds from process
valves, process drains, open-ended lines, and flanges) were also
sampled at two facilities.  The results of the air emissions
testing are presented in Appendix D.  A detailed discussion of
the air emissions associated with ethanol production is provided
in Section 3.6.

Sample Point Selection

A ^resampling  visit was made to each candidate ethanol facility
to assess the  operation of the plant and the accessibility of the
air emission point sources and wastewater streams.  The final
selection of the sample points and sample type based on the site
visits are summarized in Table 3-5 and discussed below.

Plant API.  During the site visit, it was discovered that many
major sources  of wastewater were  inaccessible.  The only  streams
that were possible to test included the bottom stream  from the
benzene  recovery column, the makeup water, and the total  ethanol
plant effluent stream.  The wastewater treatment system pretreats
all plant A01  wastewaters  before  discharge to the municipal
wastewater treatment plant.  The  effluent stream from  this treat-
ment system was not tested as  the ethanol plant wastewaters com-
prise only a small fraction of the total load to the treatment
plant.

The vents for  air  emissions were  located approximately 20 meters
from the ground and extended  from the side of the ethanol plant
building.  As  such, the  vents  were  inaccessible and no air  sam-
pling was proposed.

This ethanol plant routes  all  solid wastes associated  with  etha-
nol production to  a centralized  feed  house where wastes  from
other processes are handled.   The solid waste from  the ethanol

                                  67

-------
facility could not be sampled separately; thus, no solid waste
sampling was proposed for this facility.

Plant A03.  This plant was sampled for air, water, and solid
wastes in a 1979 program sponsored by lERL-Ci  (8).  As a result,
only two streams were selected for additional testing for Appen-
dix C compounds and priority pollutants.  For this study, grab
samples of the secondary biological treatment system effluent and
the source water were taken on two successive days.  The lERL-Ci
study did not analyze solid wastes for metals; therefore, samples
were collected from the feedstock grain, by-product grains, and
biosludge streams for metal analyses.

Plant A06.  This facility does not combine its waste streams or
treat its wastewater; therefore, only the major waste streams
(benzene stripping column bottoms, evaporator condensate, and
wash waters) were sampled.  During the test effort, it was
determined that plant A06 was operating under start-up condi-
tions.  Due to the unstable conditions of start-up operations,
grab samples were collected rather than composite samples.

The sources of air emissions that were selected include the vents
from fermenters, product storage, and the steam ejector used for
the vacuum system.  Also, the outlet from the cyclone used to
control particulate emissions from the by-product grains dryer
and a CO2 degasser vent were chosen.  These sources were hypo-
thesized to be the major sites for particulate, inorganic, and
hydrocarbon emissions.

No solid wastes were sampled from this facility.

Plant A07.  In addition to the total raw waste stream from plant
A07, the evaporator condensate stream was selected since it con-
stitutes a major portion of the total raw waste.  As in all other
plants, the makeup or source water stream was sampled to deter-
mine net values for pollutant concentrations.

Several wood pulping processes occur at plant A07 and the wastes
from these processes are combined with the effluent from the
ethanol plant. The ethanol plant contributes 40 to 65 percent of
the BODs load and 10 percent of the total wastewater volume.
Due to the high percentage BODs contribution from the ethanol
plant, the total plant raw wastewater and treated effluent from
plant A07's wastewater treatment system were selected for
sampling.

No air sampling was attempted at this facility due to the inac-
cessibility of sample points for air emissions.  Also, the solid
wastes are routed to a lignin plant and were not selected for
sampling.
                                 68

-------
Plant EOS.  The wastewater sampling at this facility was confined
to the wastewater treatment system so that treatment system effi-
ciency data could be gathered.  In addition to the total un-   }
treated and treated effluent, samples were collected for six days
from the first aeration basin effluent, the rotating biological
contactors (RBC) effluent, and the influent to the air flotation
unit.  A treatability study using a granular media filter was
also conducted for five days each on the first aeration basin
effluent and the RBC effluent (13).

The grain dust generated by the milling operation is collected by
a cyclone and baghouse in series.  The duct from the baghouse to
the atmosphere was chosen for sampling.  The by-product centri-
fuges decrease the water content of the distillers dried grains
(DDG).  Vents from the centrifuges were easily accessible on the
dryer house roof and therefore were included for sampling.  Also
accessible on the dryer house roof was the main dryer stack;
this stack was the primary point source that was sampled.  The
vents on the cooker/cooler tanks, distillation system (beer still
and reboiler) and, ethanol storage tanks were all inaccessible
for sampling.

Both inlet grain and the DDG's were sampled from bulk storage
piles.  Since the wastewater treatment system wastes no sludge,
the two streams mentioned above were the only solid streams
sampled.

Plant E09.  This plant combines all of its wastewater, except
sanitary wastes and flash cooler condensate, into a receiving
tank called the distillery, waste basin.  This distillery basin,
which is discharged to the local municipal treatment plant, was
selected for sampling.  The mixing basin, which receives all
acidic and alkaline wastes for neutralization prior to being
routed to the distillery waste basin, was also identified for
sampling.  Finally, the flash cooler condensate, which is
discharged directly to the river, was selected for sampling.

The condenser vents were located 30 meters from the ground and
were inaccessible.  The dryer house stack was rectangular and
located on top of a roof which could not support scaffolding;
thus it was not chosen for sampling.

There are two solid waste streams from this plant:  feedstock
grain and by-product grains.  Both of these streams were chosen
for sampling and analysis.

Plant E02.  In addition to total raw waste and treated effluent,
the evaporator condensate stream  (which is the major contributor
to plant waste load) was chosen for sampling at this facility.
Also, since the treated effluent stream is diluted with noncon-
tact cooling water before being discharged to a local stream, the


                                 69

-------
cooling water stream and diluted effluent were selected for
sampling.  Both the noncontact cooling water and makeup water
were to be sampled as grabs since the quality of these streams
was not expected to change over a 24-hour period.

Air emission sources at plant E02 were inaccessible for sampling.
The types of solid samples that were proposed for collection at
this facility were all three feedstocks used, the by-products
produced, and the wasted biosludge from the bottom of the sludge
thickener.  The feedstock samples included cane molasses, citrus
molasses, and the juice obtained from pressing orange peels
(pressed orange liquor).  The by-product samples included the
beer still bottom stillage and the condensed molasses solubles.

Plant A10.  Ethanol production at plant A10 is one of many pro-
cesses conducted at this facility.  The wastes from the ethanol
plant and other production processes are routed to a common plant
sewer system.  To properly characterize the ethanol plant, the
sewer line upstream and downstream of the ethanol plant was
selected for testing.  Also, the evaporator condensate stream,
which is a major waste stream, was chosen for sampling.  To
obtain treatment system efficiency information, the effluent from
the aeration pond was selected for analysis.  Truck washings of
cheese whey and brewers' yeast, which are sent to the local
municipal treatment plant, were also identified for sampling.

As with many other ethanol facilities, the point sources for air
emissions proved to be inaccessible and were not considered in
the test effort.  Solid waste streams chosen included by-product
condensed cheese whey solubles (CWS), core samples of land that
had been subjected to spray irrigation with treated effluent, and
samples of feedstock cheese whey and brewers' yeast.

3.2  STATISTICAL DATA EVALUATION

The ethanol-for fuel industry is a new industry for which limited
data are available concerning effluent quality and treatability.
To augment the data base, additional data were obtained from the
beverage alcohol industry which was hypothesized from an
engineering standpoint to be similar to the ethanol-for-fuel
industry in terms of effluent quality and volume of wastewater
generated.  Thus, there are two objectives in this section.  The
first is to determine if beverage alcohol plants and ethanol-for-
fuel plants differ significantly with respect to the amount or
quality of effluent generated.  Beverage alcohol facilities which
are significantly different from ethanol-for-fuel plants are to
be excluded from the data base.  The second objective is to
determine if there are factors which significantly differentiate
                                 70

-------
groups within the ethanol-for-fuel industry (as represented by
the available ethanol-for-fuel plants and the statistically
similar beverage alcohol plants).

The results of an engineering and statistical analysis revealed
that the three rum facilities were significantly different from
the ethanol-for-fuel facilities and the other beverage alcohol
plants in terms of effluent quality.  The rum facilities were
found to have significantly higher concentrations of TSS and
BODs because no recovery of by-product grains is practiced
(i.e., stillage is incorporated into total plant effluent).  The
statistical analysis showed no significant differences in efflu-
ent quality between the ethanol-for-fuel facilities and the
remaining beverage alcohol plants.  A detailed description of the
statistical methods used is provided in Appendix F.

AVAILABLE DATA

A statistical analysis was conducted using untreated effluent
quality data and flow rate data from 13 ethanol facilities (A03,
A06, A07f A10, E01r E02, E03, EOS, E09, E15f E17, E18, and E20).
These are the only facilities for which flow rate data and
untreated effluent quality data were available.  These data were
derived from the following sources:

     1.  1978 EPA/IERL study to characterize the waste streams of
an alcohol facility.

     2.  1980 EPA/EGD screen sampling program for effluent guide-
lines development.       ,

     3.  EPA Regional NPDES permit monitoring data.

     4.  EPA/EGD Industry Questionnaires.

     5.  1978 Region IV EPA study of rum distillery wastewaters.

The analytical parameters that were evaluated in the statistical
analyses were total suspended solids (TSS)' and five-day biochemi-
cal oxygen demand (6005).  These parameters were selected
because, historically, they have been used as indicators of water
quality in designing biological treatment systems and in monitor-
ing treatability.  Sufficient data were not available on other
analytical parameters to use them- in the statistical analysis.

The BODs and TSS data available for performing these analyses
are summarized in Table 3-6.  These data fit a lognormal dis-
tribution better than a normal distribution; therefore, natural
logarithms of the data were used in the statistical analysis.
                                71

-------
                            Table 3-6



             DATA AVAILABLE FOR STATISTICAL ANALYSES
                                                     TSS
Facility Type
E thanol -For -Fuel
A03
A06
A07
A10
Beverage Alcohol
E01*
E02
E03*
E08
E09
E15
E17
E18
E20*
No. Of
Observations

66
3
3
2
5
3
5
7
3
5
165
54
5
NO. Of
Observations
152
3
3
2
5
3
5
7
3
5
25
23
5
*Rum producing facilities
                                72

-------
 In  addition  to BODs and TSS, total plant  flow  rate as a  func-
 tion of ethanol production was evaluated  in the statistical
 analysis.  Daily observations fbr plant flow rate and ethanol
 production were not available for most plants.  Therefore, the
 analysis  considered the ratio of average  flow  rate to average
 ethanol production for each facility.

 The approach that was taken to determine  whether these facilities
 differ with  respect to average effluent quality consisted of
 performing a single classification analysis of variance, with
 facility  as  the classification variable.   This was followed by  a
 multiple  comparison procedure, which was  used  to classify facil-
 ities  into groups with similar average effluent quality.  These
 groups of facilities were then examined to determine which of
 several potential factors may have been responsible for  the
 differences  observed between groups.

 To  use the analysis of variance method, individual observations
 are needed to account for daily variation within a facility.
 However,  daily observations for plant  flow rate are not  available
 for most  of  the plants examined.  Therefore, the approach taken
 to  evaluate  flow rate was to classify  the flow ratio  (ratio of
 average flow rate to average ethanol production) using the multi-
 ple comparison procedure.   If different groups result, they would
 then  be examined  (as with effluent quality)  to determine which
 factors may  have been responsible for  the different groups.  •,-

 GROUPINGS BASED ON  EFFLUENT QUALITY AND FLOW RATIO

 The analysis of variance tested whether the  13 facilities differ
 with  respect to average effluent quality. This analysis indi-
 cated  that some of  the  13 facilities tested  had significantly
 different average concentrations of TSS and  6005.

 Duncan's  multiple range  test was then  used to  compare  the average
 concentrations of TSS or BODs  for each pair  of facilities.
 Duncan's  test classified  those  facilities with significantly dif-
 ferent average concentrations of TSS or BODs into separate
 groups,  and  those  facilities with  similar average- concentrations
 into  the  same group.  The procedure used  to  group facilities
 takes into  account  the  fact that  the  average concentrations  of
 TSS or BODs  were more precisely estimated at those  facilities
 where more  data were available.

' Table 3-7 presents  the  facilities  within  each  group and  the
 average TSS  and BODs concentration  in  the logarithm scale  for
 each  facility.  Within  each group  the  parameters  are  listed  in
 descending  order  for average. TSS  and  BODs concentration. The
 analyses shows  two  distinct groups for BODs  and TSS.   Both
                                 73

-------
                            Table  3-7

    GROUPING OF FACILITIES BASED ON  UNTREATED EFFLUENT QUALITY
                 TSS
                       Low
E01 (16.2)
E20 (16.1)
E02
EOS
E09
E15
A03
EOS
A10
E17
A07
E18
A06
(13.
(13.
(13.
(12.
(12.
(11.
(11.
(11.
(11.
(11.
(10.
4
1
1
8
8
8
7
7
6
3
0
     _BOD_5_
High
                                    E20
                                    E01
  (17.4)
  (17.3)
                                              Low
EOS
A07
E02
A06
E09
A03
A10
E18
E15
E17
EOS
(14.
(14.
(14.
(14.
(14.
(14.
(13.
(13.
(13.
(13.
(13.
7
3
2
0
0
0
8
6
6
5
1
Notes:  Groups were selected using  Duncan's  Multiple  Range Test
        Numbers in parentheses are  facility  means given  in ug/1,
                                74

-------
plants in the high groups are rum facilities.  Also, the third
rum facility (plant EOS) has the highest value in the low BODs
group and the second highest value in the low TSS group.  There
is strong evidence from these statistical analyses that the rum
facilities differ from both beverage alcohol plants and ethanol-
for-fuel plants based on TSS and BODs.  Th® rum facilities are
not part of the ethanol-for-fuel industry and are not considered
to be typical of future plants in the industry that will use
sugar feestocks.  Therefore, data from the rum facilities are
excluded from the data base for the statistical analyses.

Disregarding the rum plants, Table 3-7 shows that the ethanol-
for-fuel facilities are interspersed with the beverage alcohol
facilities.  This distribution indicates these plants cannot be
distinguished from one another on the basis of BODs or TSS.

Duncan's multiple range test was also used to compare the flow
ratios for each pair of facilities.  The results of this test
indicate that all of the facilities fall into the same group.

ANALYSIS OF POTENTIAL FACTORS AFFECTING EFFLUENT QUALITY AND FLOW
RATIO

Based on the information presented in Sections 2 and 3, the
following factors were selected as having the greatest potential
to affect effluent quality and volume from an engineering
standpoint:

     1.   Process variations
                         s
     2.   Feedstocks

     3.   Final products

     4.   Plant age

     5.   Plant size

Tables 3-8, 3-9, and 3-10 show the relationship between these
factors and the facilities grouped in terms of 8005, TSS, and
flow ratio.

Process Variations

The five major processing steps associated with ethanol produc-
tion are feedstock preparation, fermentation, distillation, dehy-
dration, and by-product processing.  As the data in Section 3
show, the only steps which might significantly affect effluent
quality are variations in feedstock preparation and by-product
processing.
                                75

-------
                                                                                         •a

                                                                                         3
                                                                                                  eo
                                                                             1
                                                                                   •o
                                                                                   1-4
                                                                                   o
                                                                             a>
                                                                                   i
                         o

                          5
                                                                             1
                                                                      £


                                                                      •rt

                                                                      S
                                                                                          •o
                                                                                          i-4
                                                                                          o
CO



CO
ca  u
                                                                       o>
                                                                                           •o

                                                                                           S



                                                                                           •o

                                                                                           S
                                                                                                   03
                                                                                                              §.
EH
                                                                                           •o

                                                                                           o
                                                                                                              U


                                                                                                              O
                                                                                                              o


                                                                                                              09
                                                                       £


                                                                       •v4

                                                                       S
                                                                                           |
a

i
a
                                                                              i
                                                                                    •o

                                                                                    o
                                                                                                                      2
                                                                                                                      u
                                                                                                                      a
                                                                                                                      •o
                                                    i

e
aluation Factor
>
a
ocess Variation
u
04
11
&
§
By-Product Reco
No Recovery



edstock
£
'
u w
Grain-Derived {
Sugar-Derived 1



.nal Product
*n
Ob
_s
Sir
i-4 i-4
O O
e e
||
e e



a
u
a
£
o
S
a
b


11
in in
-H 1-1
V A


9
?
J
O —
N >-t
a^i
^5
SS
••4
Oi

W * J
g
-1=0
-4 ~« O»
i^i
a B<->
inoe"
M mm
1 1 A

O
G
•a
S
a
•V4
f-f
Facilities are
*
                                                                        76

-------
col
o
ul
  n
  £
              •o
              3
                         (9
                                      •o
                                      3
                                                             CO
                                                •o
                                                t>4
                                                o
u
                                                •o
                                                •*
                                                o
                                                    co










^^
1


0)
JQ
(0
&^








CQ
M
M
S* o
H * g
J in o
5§ «
•< CQ *
fa J
|J O
0 fa
25
< CQ
93 «


O
Z <
63 fa
CQ
a z
£o
ta H
CO EH
*c

M J
03 <
CQ >
§H
M Q

S 2
< >•

m n


Ol QB
e 0
u >>

\0 09
O 0
< . ' >•


M n
e 0
u x


r> o
O 0
< S

<
                                    X
                           O>
                           ft
                           X
                                    JS
                                     Ol
                                                I
                                      •o
                                      s

                                      •o
                                      s
                                                9
                         CO
                                      •o
                                      s


                                      «o
                                      3


                                      •o
                                      s

                                      •o
                                      s
                                                             CO
                                                                         o
                                                                         o
                                       o
                                       u

                                       8

                                       S

                                       en
                                       iH
                                       n
                                       18
                                       O
                                                                         o
                                                                         e
     to
     o
     09
     03
     0
     O
     o
         §
         18
> o
a z
                   0
                   £
                         tn
             •an
              * *   ^
             .?«•*   o
              U M   3
             £2   3
              i  i   i     tn i J
                  10     .»,—.—
                  •o
o   .  .    _
o   eu    ft.          ^
4j  -H A        tf tf       in in
tn   looi"-*   ®o   *•   •^l~l
•o   u 3    «J   "".*,   c   v ^
    U co    e   V|A|   n
            Z          a.
..a-'k'o          e o «j
isjs        a> -H   0->   oiBi-4
4J4J   0    ZO   NrH
                  r! o
co  e   tn o o

a£   7? A
c  jj   eo
<0  U     (S
                                                                         JJ
                                                                         a
                                                                         (0

                                                                         ra
                                       o
                                       2
                             .77

-------
            09

            S
                                     o>
                                                                               o
                                                                              z
                                     O>
                                    ft
                                                                              •o
                                                                              iH
                                                                              o
oal
           i


           i
                        to
                                                                              •o
                                                                              3
                                                               CO
             a

             St-
                                                                               •o
                                                                               3
                                                                CO
                         CO
                                                                               •o
                                                                               fH
                                                                               O
eal

<\
                                   £

                                   •*
                                   33
                                                                                o
                                                                               z
 I
CO

 (I)
rt
JQ
 m
                         (9
                                                                CO
                                                  •O
                                                  s
                                                                           >

                                                                           o
                                                                           •*4
                                                                           4J
                                                                           a


                                                                           8
       EH  ca
 "I
 <=
 Cfl
              a
              £
                                                        co
                                                 i
                                                                             •M
                                                                             a
                                                                             «

                                                                             2
                                                                             o
el
Cd|
                                      o>
                                                                                •o
                                                                                s
                                                                             b
                                                                             4)
                                                                             o

                                                                             e
a

o
u
u
«
Oi
§
•4*
4J
Q
a
•H
«

a
e
ss Variatio
0
u
o
u
Oi
>
o
Product Rec
Recovery
>< o
a z



j^
0
jj
a
•o
^
                                                                               z£


                                                                               in in
                                                                               1-4 >-l
                                                                               V A
                                                                                      Ss

                                                                                      04
                                                              O-O
                                                              8 ®
                                                              a H
                                                             in o
                                                             M in
                                                              1   1
                                                             o m
                                                                    C9
                                                                    Dl
sted
2
«

a
o
•#4
JJ
•H
<-*
v4
U
A
Cu
                                      78

-------
By-Product Processing

Two methods of by-product processing are in use in the industry:

     1.   Concentrating and drying stillage to produce by-product
animal feed.

     2.   Concentrating and routing the stillage stream to
another processing unit.

The first option is used by all the plants using a corn feedstock
(A03, E09, E15, E08, and E17) and the molasses and cheese whey
plants (E02 and E10, respectively).  Plant A07 uses the second
option to process spent sulfite liquor and a by-product lignin
stream.  There is no evidence to support that the condensate
discharged from by-product processing option 1 would be signifi-
cantly different from option 2 in terms of effluent quality or
volume.

The rum plants (E01, EOS, and E20), on the other hand, discharge
whole stillage (the major source of waste in an ethanol facility)
without processing.  Although this does not affect the volume of
wastewater generated, it accounts for the high TSS and BODs
values observed for the rum facilities as indicated in Tables 3-8
and 3-9.

Feedstocks and Feedstock Preparation

Feedstock preparation techniques vary according to the type of
feedstock processed.  The plants examined had two types of
feedstock:  those requiring saccharification (grain-derived) and
those already containing high concentrations of fermentable
sugars (sugar-derived).  The detailed preparation techniques for
each class of feedstock are outlined in Section 2, Industry
Profile.

As Tables 3-8 and 3-9 show, only sugar-derived feedstocks can be
found in the group with high TSS and high BOD§ values.  How-
ever, plants using sugar-derived feedstocks are also interspersed
among the grain distilleries in the low TSS and BODs groups.
Also, Table 3-10 does not show that these factors affect flow
ratios.  Therefore, no data are available to conclude that
feedstock type or feedstock preparation techniques significantly
affect waste streams from plants in the ethanol-for-fuel
industry.

Final Products

Most plants providing ethanol-for-fuel produce the same product:
anhydrous ethanol.  In cases where the plant is a partially con-
verted beverage alcohol plant, 50 to 95 percent ethanol may also
                                79

-------
be sold as a product.  Any difference in wastewater generation
between a 50 percent and a 100 percent product is due to the
addition of a rectification column and a dehydration unit.  The
quantity of wastewater generated from these units would increase
the total plant effluent volume by less than 3 percent.  Table
3-10 also indicates that the final product produced has no effect
on wastewater production.  Furthermore/ the quality of the water
removed in rectification and dehydration is, in many cases/ bet-
ter than the intake water for most pollutant parameters.  Thus,
in accordance with the information in Tables 3-8 and 3-9, the
type of product produced does not affect the quality or quantity
of the total plant effluent.

Plant Age

The effective age of a processing operation is usually difficult
if not impossible to define because there is often little corre-
lation between the age of a plant and the age of the equipment
used within the plant.  A processor may constantly replace worn-
out equipment with new equipment, or, in some cases, install old
equipment in a new building.  Tables 3-8 and 3-9 show that plants
of different age groups can be found in both high and low groups
of BODs and TSS.  Also, Table 3-10 shows no relationship be-
tween plant age and flow ratio.  Therefore, data are not avail-
able which would support distinct differences in waste generation
and effluent quality within the ethanol-for-fuel industry on the
basis of plant age.

Plant Size

In regard to plant size, the ethanol production capacity varied
from 17 cubic meters of anhydrous ethanol per day .at plant EOS to
230 cubic meters of anhydrous ethanol per day at plant E09.
Effluent quality is not a function of plant size as Tables 3-8
and 3-9 show; plants of different size groups can be found
interspersed in the high and low TSS and BODs groups.  Further-
more, Table 3-10 shows that the wastewater generated to ethanol
produced ratio does not vary as a function of plant size.

3.3  WATER USE AND EFFLUENT SOURCE

As Figure 3-1 illustrates, the sources of wastewater from an
ethanol plant include flash cooler condensate from cooking and
cooling, rectifier bottoms and beer still bottoms from dis-
tillation, benzene stripping column bottoms from dehydration,
evaporator condensate from by-product processing, equipment wash
water, noncontact cooling water, boiler blowdown, and ash sluice
water.  In most ethanol plants, the noncontact cooling water
stream is discharged directly without treatment and seldom com-
bined with ethanol plant wastes, although the noncontact cooling
water at plant E02 is combined with the treated effluent to
dilute the final discharged effluent.  Because the noncontact

                                80

-------
                                                            BO


1
JJ
a
{
b
J

"So
'3,
o
u
t

i
jj
09
•o
01
01
u.




I

F*
0
o
D


— <
JJ
(8
CO
O.
01
u
fti


01
JJ
1


V)
01 01
1-1 JJ
J<8
09
— •• - oi
45-0
09 e
OS 0
ta


01
JJ
*~ JJ
09





















lation
1-4
JJ
09
i-l
O


3-
o c
If
•Sfi
1
s
•r
Ji
0
]

J





t
1 JJ
> l-i
leu
t
i
j
i
i
?
!

i
•H
U-l
JJ
OS

T-4
1-1 -<
01 JJ
« M

k




H«e








09 O
01 O
£4 u
o a
CO *•* t
o '
1 p
O S5
60
CLO
O.JJ
1-4 JJ
V4 O
II
01
oa
0) CO
U 0 0
u o pa
"

0 ><
9 V4
•O 0)
, ° *
* fcl O
o. u
1 01
O (3
•g*
58
4 9
i! Hf3
j oi co
ell










                                                                               0)
                                                                               00
                                                                               •H
                                                                               Em
                                                                     CO

                                                                     I
I
                               81

-------
cooling water is not treated in the ethanol-for-fuel industry,  it
is not addressed in this document.  Also, boiler blowdown and ash
sluice water are not considered as there is no data available
from ethanol plants which use coal-fired boilers.

The extent to which each of the remaining wastewater sources con-
tributes to the total plant raw waste varies and is a function of
several design and process parameters, including the choice of
biomass feedstock, the form and extent of by-product recovery or
extraction, the reuse and recycle of water streams, and the pro-
duct quality desired.  Table 3-11 presents the approximate per-
centages that each of these streams contributes to the total
plant wastewater volume for three grain distilleries.

3.3.1  COOKING AND COOLING

Depending on the type of equipment used in cooking and cooling of
the mash, a potential source of wastewater is the condensate from
flash coolers.  A flash cooler is used to cool the cooked mash to
a temperature suitable for conversion.  This is accomplished by
subjecting the mash to a partial vacuum? the subsequent evapora-
tion of liquid causes a loss of heat.  The condensate from this
evaporated liquid amounts to 0.3 ,to 1.0 m3 per 1,000 kg of
grain processed (8,14).

Priority pollutant analyses conducted at plant A10 for the flash
cooler condensate stream revealed no toxic compounds present in
amounts greater than 10 ug/1.  BODs values for plants A03, E09,
and E14 varied from 13 to 1,900 mg/1, with an average of about
900 mg/1.  The BODs concentration of the flash cooler conden-
sate is related to the entrainment of dissolved organic sub-
stances in the flashed vapors.  This entrainment is a function of
the type of equipment used and the efficiency achieved.  Total
suspended solids were low, with mean values of 5 and 30 mg/1
obtained at plants A03 and EO9, respectively.  The pH for plant
AO3 was 3.4, while a value of 7.2 was determined for plant EO9.
The high 8005 and low pH for plant AO3 suggests the presence of
organic acids in the condensate stream.

3.3.2  DISTILLATION

There are two significant sources of wastewater from the distil-
lation system:  the beer still bottoms and rectifier bottoms.
The bottom stream from the beer still, referred to as stillage,
is routed to by-product recovery and, therefore, is discussed in
a later section.

The amount of wastewater generated by concentrating the ethanol
product ranges from 0.43 m3 per 1,000 kg of grain processed for
a grassroots ethanol-for-fuel facility  (A06) to 1.4 m3 per
1,000 kg of grain processed for a conventional ethanol facility
such as A03  (308 Questionnaire, 198u).  Plant A10 uses a cheese

                                 82

-------
                              Table 3-11

             PERCENT VOLUME OF TOTAL UNTREATED EFFLUENT
            FOR GRAIN DISTILLERS WITH BY-PRODUCT RECOVERY
By-Product Recovery

Cooking/Mashing

Rectifying

Cleanup

Dehydration

     Total
Plant E09(l)

    77

    11

    10

     2



   100%
Plant E19(2)

    50

    36

     7

     7



   100%
Plant A03(3)

    66

    14

    28

     1

   	1

   100%
Sources:   (1) ESE, 1974, Reference 14
           (2) Middlebrooks, Reference  15
           (3) Industry, Questionnaire Response
                                  83

-------
whey feedstock and produces 0.58 m3 of wastewater per 1,000 kg
of feedstock (308 Questionnaire, 1980).  The volume of rectifica-
tion wastewater is a function of the concentration of ethanol
entering the rectifier and the source of energy (heat) used to
separate the ethanol and water.  When the rectifier feed is
derived from the beer still, a 60 to 80 percent ethanol stream is
concentrated to 95 percent in the rectifier.  When purification
columns are used, the feed to the rectifier may be only 10 to 20
percent ethanol (the beer still product is diluted in purifying
columns) and likewise must be concentrated to 95 percent. Also,
it is estimated that the use of direct steam injection rather
than reboilers as a source of energy to accomplish the separation
of water and ethanol can increase the wastewater volume from
distillation by 20 percent (14).

Conventional analyses conducted for the rectifier bottom streams
exhibited BODs values for plants A03, A10, and E13 that were
Ir440, 277, and 300 mg/1, respectively.  The total suspended
solids concentration for plants A03 and A10 were below the 1 mg/1
detection limit, while the pH values were 4.7 and 6.2, respec-
tively.

Priority pollutant analyses were conducted for the rectifying
columns at plants A10 and A06, which integrates the dehydration
and rectification processes.  The priority organics detected at
values greater than 10 ug/1 were the same for both A06 and A10,
these included methylene chloride, bis(2-ethylhexyl) phthalate,
and phenolics (4AAP).  The priority metals which were present at
levels above their detection limit for both A10 and A06 included
cadmium, copper, lead, and zinc.  In addition, chromium and
nickel were found only at plant A06.

3.3.3  DEHYDRATION

In typical dehydration schemes, the remaining water is removed
from the 95 percent ethanol product via the bottom stream of the
solvent stripping column and/or dehydration column.  These
streams are small, amounting to 0.002 m3 per 1,000 kg of grain
processed, and are independent of any processing variables (8).

The concentrations for 8005, TOC, TSS, pH, and phenolics for
the solvent stripping column bottoms from plants A01 and A03 are
presented  in Table 3-12.  The concentrations of these species  in
the stripping column bottoms stream are quite low in these param-
eters.  Additional priority pollutant analyses at plant A01
demonstrated the only organic compound present was methylene
chloride at 22 ug/1.  The priority metals present at levels above
their detection limits included chromium, copper, and zinc at
4.0, 6.0,  and 10.0 ug/1, respectively.  An analysis for benzene
in the wastewater stream from the dehydration column and benzene
stripping  column at plant A03 exhibited concentrations of 59.4
ug/1 and 5.7 ug/1, respectively  (8).

                                 84

-------
                           Table 3-12

              SOLVENT STRIPPING COLUMN BOTTOMS FROM
                        DEHYDRATION SYSTEM
                      DISCHARGE VALUES (mg/1)
                                      Plant API     Plant A03


           BOD5                         26.0          16.0

           TOG                          15.0           8.0

           TSS                          <1.0           1.0

           pH                            3.9           4.1

           Phenolics                    <0.01           *
*Not analyzed.
                                85

-------
3.3.4  BY-PRODUCT RECOVERY

By-product recovery consists of concentrating the stillage from
the bottom of the beer still in the centrifuges and evaporators,
then drying the concentrated stillage in dryers.  The evaporator
condensate from this process is a major source of wastewater.  In
addition, the volume and quality of the condensate produced
varies greatly.  As Table 3-11 illustrates, evaporator condensate
comprises 50 to 70 percent of the total volume of ethanol plant
wastewater.  The flow for evaporator condensate varies between
2.2 and 4.1 m3 per 1,000 kg of grain processed.  Alternate
feedstocks such as cheese whey or sulfite liquor generate 1.6
m3 per 1,000 kg of cheese whey and 0.78 m3 per 1,000 kg of
sulfite liquor, respectively (308 Questionnaire, 1980).  Regard-
less of feedstock, this variation is a function of the stillage
concentration entering the evaporators and the percent of still-
age recycle to the cooker or conversion tank.

Another source of wastewater from by-product recovery is the
blowdown stream from wet scrubbers; these are used to remove
particulates from grain dryer exhaust gas.  Plant E09 estimated
that the load from this source constituted 37 percent of the
total load from by-product recovery.  Dry particulate collection
devices such as cyclones are in use at most plants to eliminate
this source of waste.

The sampling and analysis of evaporator condensate was done for
four plants which differed in feedstock.  The conventional
parameter analyses demonstrated wide ranges for BODs and pH.
The BODs varied from 628 mg/1 for plant A06 (grain) to 4,835
mg/1 for plant A07 (sulfite liquor).  The molasses and cheese
whey feedstock facilities had BODs's of approximately 2,550
mg/1.  The pH ranged from 2.9 for plant A07 (sulfite liquor) to
7.95 for A10, the cheese whey facility.  The high BODs concen-
trations and low pH values imply that the contributing substances
are primarily volatile organic acids.

A priority pollutant characterization of evaporator condensate
for the four plants mentioned above is presented in Table 3-13.
This table illustrates that few priority pollutant organic com-
pounds were present.  All the organics listed except methylene
chloride, bis(2-ethylhexyl) phthalate, pentachlorophenol, phenol,
toluene, and di-N-butyl phthalate were observed only once.  Most
of the priority metals were detected.  All the metals except cad-
mium, chromium, copper, lead, nickel, and zinc were found only
once above their detection limit.

3.3.5  WASH WATER

The risk of contamination from bacteria and other biological or-
ganisms which compete with the yeast and lower the alcohol yield
have necessitated weekly cleanups and sterilization of the feed-
stock preparation vessels and fermenters.  The amount of wash
                                86

-------
                         Table  3-1.3

       EVAPORATOR CONDENSATE CHARACTERIZATION:
                   PRIORITY POLLUTANTS
Organics. A06
(ug/1) 1 {Grain)
aero le in
chlorobenzene
1,1,2-trichloro-
ethane
1,2-dichloro
propane
• thy 1 benzene
methylene chlor-
ide
pentachlorophenol
phenol
bis(2-ethylhexyl)
phthalate
toluene
cyanide
di-N -butyl phthalate
tetrachloroethylene
Metals (uK/l)2
antimony
arsenic
beryllium
cadmium
chromium
copper
lead
nickel
selenium
silver
zinc
11
—
...
..

--
34
—
—
6.0
—
i,~'
'—
16

—
1.0
9.7
17
862
160
168
.—
-.
36
(Sulfite
Liquor)
16
15
15

7.5
54
20.5
98
39
.10
20
--
—
2.3
1.3
—
13 '
17.7
15.7
79
45
1.7
1.3
74
                             A07
                                        £02
                                         17.5
                                         13.5
                                         10.5
                                          1.5
                                          1.0
                                          9.5
                                         13.5
                                         17
                                         26
   A10
(Cheese
  Whey)
  150
   74
  80
  118
1Priority pollutant organics  with at least one maximum concen-
 tration greater than 10 ug/1.  Average concentrations are
 listed.

^Priority metals with at least one analysis above the detection
 limit  for that element.  Average concentrations are listed.
                              87

-------
water generated during sterilization and cleanup and the waste
load varies from plant to plant according to the final product
purity requirements, operating procedure, plant management
practices, types of equipment, and plant design.  The amount of
wash water produced for the seven ethanol plants tested ranged
from 0.45 m^ per 1,000 kg of grain processed to less than
0.04m3 per 1,000 kg of grain processed of wash water at plant
A06.

Priority pollutant analyses of the wash waters from plants A06,
E09, and A10 yielded no toxic compounds present at concentrations
higher than 10 ug/1.  Conventional pollutant analyses showed
BODs concentrations ranging from 48 to 1,760 mg/1, TSS concen-
trations ranging from 63 to 1,180 mg/1, and pH values ranging
from 4.0 to 12.0.  Oil and grease was a significant pollutant
parameter at plant E09, with an average value of 137 mg/1.
Plants A06 and AlO had oil and grease values of less than 25
mg/1.

3.4  WASTEWATER CHARACTERIZATION

This section summarizes the analytical results obtained from the
sampling programs and data collection efforts for the total plant
untreated effluent.  All the concentrations listed are absolute
concentrations of the raw wastewater; no adjustment has been made
for the species1 presence in the plant intake water.  If a param-
eter was reported at "not detected" it was assigned a value of
zero for computational purposes.  In cases where a parameter was
never detected in any analyses, a dot appears in each of the
columns to the right of the number of analyses.

Concentrations for metals were occasionally reported by the
analytical laboratory as "detected less than X," where X equals
some detection limit.  In these cases, the exact concentration is
unknown and the parameter is reported as being detected, but at a
level less than the detection limit.  For computational purposes,
the method that has been used in the past by the Agency for
quantifying the values reported as "detected less than X," where
X equals some detection limit, is to represent the value as
one-half of X.

Historically, the Agency has considered 10 ug/1 as a realistic
lower limit for detection of organic compounds.  The total number
of samples where a detected value of greater than 10 ug/1 was
found is indicated since these concentrations are "quantifiable
levels."  In regard to metals, the detection limit varies accord-
ing to parameter and the laboratory that conducts the analyses.
Therefore, the number of times a metal was detected above the
particular analytical laboratory's detection limit is indicated.
                                 88

-------
 The  statistics  used  in  this  section include the minimum,  median,
 mean, and maximum  reported concentrations.   The statistical  val-
 ues  for median, minimum,  and maximum are  based  on all  the analy-
 ses  performed.  However,  because  the number of  analyses performed
 varied from  plant  to plant,  the mean concentration reported  for a
 specific parameter is an  average  of the mean concentrations  of
 each plant.   For the statistical  analysis,  if a parameter was not
 detected in  an  analysis,  it  was given a concentration  of  zero and
 if the reported species concentration was "less than X,"  it  was
 given a value of one-half of X.

 The  tables listing priority  pollutant metals, cyanide, and asbes-
 tos  also include the 90 percent value (90 percent of the  detected
 values are below this concentration)  and  the standard  deviation.
 The  tables presenting data on conventional  parameter's include
 the  95 and 99 percent values,  as  well as  the standard  deviation.
 Statistical  percentages such as the 95 percent  level were not
 calculated for  priority pollutant organics  and  nonconventional
 parameters which lacked a significant number of detections.

 3.4.1  ETHANOL  PLANT UNTREATED EFFLUENT

 The  analytical  results  for priority pollutant organics, priority
 pollutant metals,  conventional pollutants,  and  nonconventional
 pollutants are  summarised in this section.   These results repre-
 sent the total combined untreated effluent  from ethanol plants
 A01, A03, A06,  A07,  A10,  E02,  EOS,  and E09.

 It was not possible  to  sample  a combined  untreated  effluent
 stream at plant A06 or  A10.   For each parameter,  the total raw
 wastewater value was calculated by  taking a weighted average
 (flow rate basis)   of the concentrations for  each  of the streams
 contributing to the  total plant effluent.   The  weighted values
 were determined by flow ratios obtained from plant personnel in
 their responses to the  308 questionnaire.

 Priority Pollutants

 The  analytical  results  for priority  pollutajnt organics listed in
micrograms per liter  (ug/1)   are presented in Table 3-14.  Ten
 organics were found with at  least one  maximum concentration above
 10 ug/1.   Only five of  these ten were  present at  two or more
 plants, these included  bis(2-ethylhexyl) phthalate, chloroform,
methylene chloride, pentachlorophenol, and phenol.  The mean
values for chloroform (27 ug/1) and  phenol  (33  ug/1) were
 significantly influenced by  the high  concentrations found at A07
 and E02,  respectively.  For  the remaining five  organics found at
 levels above 10 ug/1, butyl benzyl phthalate, toluene,  and
 trichloroethylene  were  found only at  plant  E09.  Benzene and
ethylbenzene were only present above the 10 ug/1  level at plants
A01 and E02, respectively.


                                89

-------
    co g

    COO
    Ed PS'
    COO
en
    «a
    OO
               i:
               St

SSA

rfgg
gi"
Big
         O •  • • -etg -O	{S *®	«











         o •  • • -em -o	«e •«	I*
                  B                     ^  »        w















         o .  • • -O" -e	« «o	«










         O •  • • -OO -O	O "O	O








         O *  • • -On «O ••••«••••••  »^» «M • « • • •*
                                     eo—oooooooooooowooooooojf
                                                        ICtCllCINnCltllMNMM
                                                      lUIZ'^Z Ul
                                                      :*£>fi So,


                                                                   s:
                   w3o.ii.zu.g<  
-------
«
            «i

            fi
            §i
            fcl
                     000
                     OMO
                                                  • e
                                                   n
                     ooe
                    ooo
               :o A




                 M
                .22
                    ^nmooooinooopooveoeoooooooooooeo
                             ^ ^* TJ

                             •^12  ?!

                              Sr'^ -'
        JS
        S5^^

        g|l§

ssij  u.gg?II
IM5A  2S^?S5
                                        u. S£  Z
                                        O u u ui  *•*
                               Km  Xuu
                             *  - I  I  U Z Z    Ml SB U IU •
                             • ZZZ  ouiu  oeueooooMuj

                       :~i5Z-^!!!  ^s|gss^^ii -*s
                     ooooooaoiuwui
                        91

-------
•o
0)
    i8
    WH

    W<
    [d O
    wen
    >iO
1  11
U    H
\>x  EH 9

?  13
 0)    ><
r-4  WH

*§  aS
H  blO
    H H
               «s
               JSz
               i!

               ii
               Si

                      o

                      1
                          n
                                         rone GO .»••••<>«
                                           CO    ^
                                        •OOOOOO -O • •  • -O
                                                  >MI
                              ii!
                               o ci ei en « w c



                                                                    O
                                                                    CZ
                           u»ce
                                                             ui p
                                                   — — v — •— ' v v — — ---
                                                  w oo-j«J i-J *-«H J ^ ^ w

-------
   is
   CO M
^^k    52
•o  to <
<
>!  WH
to  oS
H  gg
   ^g
            2
            e


            I

            li

            ii
            s!
            5!
            Ml

            I
                • 8
                I A

              «e
                           • o • -o
                    ooooooo~oo«oooooooooooe
                                 § 2
                            ljgJ(Bfc-|


                          °J<551||1



                   :;fjjjiy;1jjB!;jil!!!!
                      IS^pS^i:

                      ISSl^Si
                                      oau^z
                                     F»"»»«»»
                        93

-------
All of the priority metals are listed in Table 3-15 and were
detected at levels above their detection limit.  The cadmium and
lead analyses performed for the untreated effluent at plant EOS
have been omitted from the table as the detection limits of the
analytical laboratory-for plant EOS were significantly higher for
these compounds than those limits achievable at the other labora-
tories.  Mercury was the only metal limited to a single facility,
EOS.  The analyses for cyanide demonstrated only a single value
above the detection limit, 10.5 ug/1 at facility A10.  The asbes-
tos testing was performed at plants A06, A07, and E09.  No
chrysotile or fibrous asbestos greater than 5 micrometers was
found at any of these three facilities.

Conventional Pollutants

The concentrations of conventional pollutants, listed as milli-
grams per liter  (mg/1), are summarized in Table 3-16.  In
addition to the EPA Multimedia Sampling Program results, the
daily monitoring  information obtained from the sampled facilities
as well as several other beverage alcohol plants  (E06, E07, El5,
E17, and ElS) have been included.  As mentioned earlier, the mean
value reported for a  specific parameter was determined by finding
an average of all the plants' mean concentrations.

The BODs, total  suspended  solids  (TSS), and oil and  grease  are
all present at average concentrations of  1,405; 406;  and 186
ma/1,  respectively, which  are much higher than those for typical
domestic sewage.  A wide range  is evidenced for pH,  which varies
from 3  to  13.

Nonconventional  Pollutant  Parameters

All parameters which  were  tested  that  are not classified as con-
ventional or  priority pollutants  are summarized  in  Tables  3-17
through 3-19  as  nonconventional pollutants.   The  nonconventional
metali are  listed in  Table 3-17.   All  of  these metals, except
bismuth, were detected  one or more times  above their detection
limit.   However,  palladium and tellurium  were only  found at plant
E09 while  platinum was  only present  in the  untreated effluent  of
plant  A07.   The  remaining  nonconventional metals  were found at
two or more facilities.   Aluminum,  calcium,  magnesium,  sodium,
 iron,  and  phosphorus  were  found at levels above 1 mg/1  with
values of  1.2?  550; 38.5;  1,060;  5.4;  and 63.9,  respectively.

Table 3-18 presents the results of the analyses for those  com-
 pounds listed in Appendix C of the 1977 Consent Decree  (Appendix
 C Compounds).  The compounds present at levels greater than 10
 ug/1,  at least once,  included:  acetone,  diethyl ether,  methyl
 ethyl ketone, and the n-alkanes.   The n-alkanes were found only
 at plant EOS.
                                  94

-------
ro
•8
H
                     V)
                             o
                             o>
                             a
                             M

                             O
                             I/I
                                     «M«wo•--
                                            ^u»   in  w-
ocoeor»(c oocn »-o« « r- o
                      » o>
                        in
ifltoininmai
      «-«•»-
         o
ui CM
CM      m
                                        ^or^MAvo^in^
                                            »•»   in  t-    *-«
                                              n              «
                                                                  -wo
                                                                    o»
                                                                    o
                             -MO
                                o
                                e
                                                                  •»•«
                                                                  -on
                                                                    »
                                                                  -ou>
                                                                  in
                                                                  *xlfl

                                                                  *g
                                                                  IU<-
                                                              -»  ws.

-------
10
rH


CO


 




I
to
53<
                o
                Ul
                UI2
                to<
                      •2!

                      j«
                       8
                       o
                       £
                       M
                     BUI
                  3   CB
                                       »«r w   •*•
                                 omono
                                 M Ul CD *• W

                                     <•   n
                                         §«O«eo
                                         iu5»-(D

                                       5 w  M
                                 nnmor>
                                   Sr~<0 •»
                                   Oeo  O
                                 nOBCDin
                                   So^  o
                                   in     n
                                 •OOWrtf-
                                   S^
                                   CM NO] CO
                                         g
                                   (/>
                                   Ul
                                     8111  Z
                                     M  Ul

                                 <*"uii/r«/>
                                   M  «-<
                                                  96

-------
MM
       M
       a
  .   1
  Ul   H

^SJBS

felSSS
t-«/>-eo — O en eo N
                       i      mm    «-
                             00
                             n
                                           *-«MeoNin
                                             inn
                                               ID
                Sr-f»u>T-»-inc>'-
               _M*-t*(0vC4  COO
              in    —i
                       — M  COO N
                             in —
                                    ID en
                                      to
                                      CO
                                      o
              in
                    COON
                                '<-  »-o  in
                                             w   3~*
                                     \<  J  gJ^

                           
-------
00

 CO
SCO
W frf

CO !H
ww
w>2
>•<
3 22
    g:§
    W £

    QO
    Cd U

    5o
    WK
             MI:

             Ii
             E!
                                    •8
                                     • —o>«
                                      <^«
               iel
               iui
               ci-o
               «s
              1K
                
-------
'<-   «> '*-
                                     g
iH   .H
in   CM
                     oo in r* o? in
                     VO iH CM 3s rH
                       CM CO CM
                                     i-l   VO CM Q CM
                      8
    co
                                                              CO
                       foco
                       OOCM
                                     C«J
                                                     O
          CO
          0)

          1
                                                     CN  iHiHi-IOJ   CM
                                                     CM  CMrHrHfM   CM
                                   1
                                                                    I
                                                                  %$
                                        •alt
          8
                           a
                           -H
*• **. »±3 ^ 	 **!

lilitg
CD to 0)    mp
•ej -H T"i Q ffl -H
Q Q sfi 2 13 13
               iH
                           I
                                            99

-------
Table 3-19 presents the remaining nonconventional parameters
including those analyses conducted in the field.  All the param-
eters listed had quantitative results reported except residual
and total chlorine, which were either not present or present at
levels below the detection limit of the analytical techniques.
The high mean values of chemical oxygen demand (COD) and total
organic carbon (TOG) at 2r618 mg/1 and 852 mg/1, respectively;
are consistent with the high BODs concentrations reported in
Table 3-16.  Phenolics were found with a maximum concentration
above 10 ug/1 and were also present at two or more plants.

3.4.2  TREATED EFFLUENT

Three of the plants sampled in the EPA Multimedia Sampling
Program had wastewater treatment systems which could provide an
indication of the treatability of ethanol plant effluents, these
included plants A03, E02f and EOS.  All three of these plants
were sampled for priority, conventional, and nonconventional
pollutants with a few exceptions.  Appendix C compound analyses
were not conducted on the treated effluent of plant E02.  Also,
one day's sampling for priority pollutant analyses at plant A03
is taken from the 1979 lERL-Ci study conducted by Radian
Corporation.

Priority Pollutants

Table 3-20 summarizes the priority pollutant organic analyses
conducted for ethanol plant treated effluent streams.  The
compounds found at least once with a maximum concentration above
10 ug/1 include:  bis(2-ethylhexyl) phthalate, chloroform,
methylene chloride, phenol, and 2,4-dimethyl phenol.  Only
bis(2-ethylhexyl) phthalate and methylene chloride were present
more than once, the mean concentrations of these two compounds
were 40 ug/1 and 11 ug/1, respectively.

The priority metal analyses which are summarized in Table 3-21
demonstrate that 10 of the priority metals were present one or
more times above their analytical detection limit.  As mentioned
earlier, the lead and cadmium analyses for EOS have been excluded
due to the much higher detection limit of the analytical labs for
these parameters at that1 particular facility. Four metals were
detected in the treated effluent at only one facility including
antimony, lead, mercury, and selenium.  The remaining six
priority pollutant metals (arsenic, cadmium, nickel, chromium,
copper, and zinc) were found at levels above their detection
limit at two or more ethanol plants.

Conventional Pollutants

The analytical results for conventional parameters present in the
treated effluent are summarized in Table 3-22.  In addition to
the data from plants A03, E02, and EOS, data on the BODs

                                100

-------
     £
       w
      10
     wq
     tdOd

S   "°
7   S&i
 X  u
                             uuiu       P  IU>£  uuiux£xXMMMMMa:5
-------

             1
0}
     !PM
                    I
                    §
                    o
                    I
                   tl-O
                                102

-------
   2 W

~  IS
•o  cos

d  w q
c  WP*
•3  WO
4J  >"
C  >JH
    !O
    Ck
 0)
     ff!
H  QO
                        j;g&u,^^isgsssii|  |
                        «%»^^^^ t>i ri ^« u IM w w ^ tar B lu  K
                          liglBSBBSSHlH&HHE
                        103

-------
 0)


 I
 4J

 O
 u
 o
•M
  i '  . . . i i  i i i  -iii
                        z   "w »€>i««M«
-------
            o
            u
   W!
4J
I

n
•s-
H
i|

ii
                   5
                   S
                   z
                        ooooooo
                            105

-------
oj
I
ctf
H
    wo
              a
              Ul
              N
              •:
               01
                   s
                   a
                   Q
                   HI
                Ul
                    M
                  Kill
                 IM
                 HZM
                                     ^1  ^ w
                               (0    C4 t
                           »-o —inowoooo —in
                         ?isi?s5  iigsg^
                         OH>-KO«IH''^H«SO2Pj
                                 •» 1.0,6

-------
 Ol/>   U

-------
(total), fecal coliform, oil and grease, total suspended solids
(TSS) concentrations, and pH values for this table were obtained
from the 308 Questionnaire responses that were received from the
seven beverage alcohol facilities (plants EOS, E06, E07, E13,
E15, E17, and E18).

Both the BODs and total suspended solids concentrations have
demonstrated significant improvement over the untreated effluent
concentration, with mean values of 26 mg/1 for 8005 and 49 mg/1
for TSS.  The pH values for the treated effluent are all within
the range of 6 to 9.

Nonconventional Pollutant Parameters

Tables 3-23 through 3-25 present the analytical results for non-
conventional pollutant parameters in the treated effluent from
plants E02 and EOS.  The nonconventional metals (Table 3-23)
which were not present at concentration levels above their ana-
lytical detection limit were bismuth, palladium, platinum, and
tellurium.  Also, four of the nonconventional metals were found
only at plant E02; these metals included molybdenum, tin, vanad-
ium, and yttrium.  Aluminum, calcium, magnesium, sodium, and iron
were found at levels above 1 mg/1 with values of 2.9, 165, 3.7,
50.2, and 2.6 mg/1, respectively.

The Appendix C compounds for plant E02 are summarized in Table
3-24.  The only compound found above 10 ug/1 was acetone at a
concentration of 43 ug/1.

Finally, the remaining nonconventional parameters are summarized
in Table 3-25.  The average values for COD and TOC were reduced
from 2,618 mg/1 and 852 mg/1 in the untreated effluent to 460
mg/1 and 182 mg/1, respectively.

3.5  WASTEWATER POLLUTANTS OF CONCERN

The Agency has studied ethanol-for-fuel wastewaters to determine
the presence or absence of toxic, conventional, and selected
nonconventional pollutants.

One hundred and twenty-nine toxic pollutants  (known as the 129
priority pollutants) were studied pursuant to the requirements of
the  Clean Water Act of 1977 (CWA).  These pollutant parameters,
which were listed in Table 3-2, are members of the 65 classes of
toxic pollutants  referred to as Table 1 in Section 307(a)(l) of
the CWA.  The five conventional pollutants identified in Section
304(a) of the CWA were listed  in Table 3-3.   The nonconventional
parameters which  were presented in Table 3-4  include, but are not
limited  to, a group of Agency-selected nontoxic metals and the
species  listed in Appendix C of the 1976 Consent Decree.
                                 108

-------
fO
CN

 I
n


 
                            o.
                            IU
  «  g
  111  H
_1_IU1UH-
<0.>IUM

slsss
HWXQJ
                          o:12
                        ^ui^
                        (
                «•    CM<
                                            CM
                                            in
              mo*mooeoinoe)CMO^o
                	r-CMincono  oocooin

                «~     *" CM      r» *• *~

                          S
                                    "
                                            s
                                  t ^     v in   ^   o> o>

                                           5       CM

                                           CM
                                      «om«mmcino««inno
                                     j M <» w w w in  inoinMinvmo   oe>   in
                                            in      o> M    *-o>   n   r»o>
                                            w      GO        n
                                            ID      *•        ^
                                                              w
                in
                                                   CM CO
                                    CO!DO<*CD«CM~COCDCMOOCO O CM t CO CM CM «
                                    COCOrMCOCOCOMMCOCOCOCMCMCOCMCOCOCOCMCOCD
                                                      109

-------
&
     I W

      H
0)
!-4

I
    CO
    Ml
    CO'

    >ii
H25
Sao
H M

j z
    ws

    QS

    "5

    ^i
               §1
               si
               I
                      Ul
                    (HO
                            Moooeoooooooctoo
                                             >  Z »>
                                             Z J«Z
                            (•uDoaeoooa
                                              -H
                                              izm
                                 110

-------
                                                               co
               8
IT)
I
                               govooor-ii-Hi-HOomococpocg
                               COCOOOCDCOvOvDVOiHOOr^CO VO CO
                               ooooaooooooovoaNcoaor^covocom
rH

%
                                                                I
                                 tn  to
                                 01  to
                                    "i P  _  «5 J"«5 -3 O
                                             «
«
CO
            fl

-------
A review of environmental regulations reveals that no federal
regulations specifically apply to. the effluents from either
ethanol-for-fuel facilities or beverage alcohol facilities.  In
?he absence of effluent guidelines, National Pollutant Discharge
Elimination System (NPDES) permits have been issued to Distillers
based on "best professional judgment," under authority of Section
402(a)(l) of the Federal Water Pollution Control Act.

The EPA regional offices and state agencies have typically
regulated suspended solids (TSS) r biological oxygen demand
(BODc) and pH for beverage alcohol facilities based on best
professional judgment.  From this study these parameters have
Ilso been selected as those potentially requiring reduction or
control before discharge based on amount of discharge, treata-
bility, costs and- treatment technology.

Total Suspended Solids

Total suspended solids  is a measure of the  suspended material
that cJn *e removed from the wastewater by  laboratory filtration,
but does not  include coarse or  floating matter  than,cano°e.
readily screened or settled out.   Generally, suspended solids
include both  organic and  inorganic materials.   The  inorganic
exponents  include sand,  silt,  and clay.  ™e organic .£«*ion
includes such materials as grease, oil, fibers, and various
materials  from sewers.

The suspended solids from an ethanol  facility  would most likely
be oraanic in nature such as entrained fibers  and insoluble
 Biochemical Oxygen Demand

 Biochemical oxygen demand is a measure of the oxygen consuming
 capabilities of organic matter.  Materials which may contribute
 to BOD include:  carbonaceous organic materials usable as a food
 source by aerobic organisms; oxidizable nitrogen derived from
 nitrites* ammonia, and organic nitrogen compounds which serve as
 food for specific bacteria; and certain chemically oxidizable
 materials such as ferrous iron, sulfides, sulfite, etc. , which
 will react with dissolved oxygen or which are metabolized by
 bacteria.
 The raw wastewater from an ethanol facility has^a mean    -
 concentration  (total) of 1,405 mg/1.  Approximately 80 Percent of
 this loading is dissolved organic materials.  The high concen-
 tration of BOD5' approximately seven times normal domestic
 sewage? requirls that this parameter be reduced before
 discharge.

                                  112

-------
 pH

 Although not a specific pollutant, pH is related to the acidity
 or alkalinity of a wastewater stream.  It is not a linear or
 direct measure of either; however, it may be properly used to
 control both excess acidity and excess alkalinity in water.  The
 term pH describes the hydrogen ion-hydroxyl ion balance in
 water.

 Data from the sampling program indicate a pH range of 3 to 13.
 Because extremes of pH or rapid pH changes can stress secondary
 biological treatment systems or kill  aquatic life, this
 parameter must be controlled.

 Other Pollutants

 The Settlement Agreement in Natural Resources Defense Council,
 Incorporated vs. Train,  8 ERG 2120 (D.D.C.  1976),  modified March
 1979,  which precedes the CWA, provides for the exclusion of
 particular pollutants,  categories, and subcategories.   The
 ethanol-for-fuel industry is not one  of the 21 industries
 included  in the  Settlement Agreement  and  the provisions of this
 agreement do not necessarily pertain  to the ethanol-for-fuel
 industry.   However,  the  pollutant exclusion criteria developed
 are logical and  reasonable means for  determining whether
 parameters should  be omitted from regulation.  Therefore while
 EPA is not developing regulations for this  industry, these
 criteria  (summarized in  Table 3-26) will  be considered  along
 with other criteria  in  the determination  of pollutants  of
 concern for the  eJbhanol-for-fuel  industry.
                        \
 All  of the  priority  pollutants  and nonconventional  pollutant
 parameters are not among  the pollutants of  concern  for  this
 industry  for  reasons  discussed  below.   In addition,  two
 conventional  pollutants  (fecal  coliform and oil  and grease) have
 been excluded as they are  process  and  plant  specific.

 Exclusion  of  Priority Organics

 Pollutants  Not Detected by Approved Analytical Methods

 Historically, the  Agency has  determined the  detection limit for
organic priority pollutants  to  be  10 ug/1.   This level  is  the
minimum concentration at which  the signal-to-noise  ratio was of
 sufficient magnitude  to give  a  quantifiable  value for the  specie
concentration.  Therefore, pollutants that are detected concen-
trations equal to  or  less than  10  ug/1 as well as pollutants not
detected in any stream can be eliminated from regulation  (Crite-
rion 3).  The compounds detected at values greater  than 10 ug/1
in the untreated effluent are presented in Table 3-27.
                               113

-------
                       Table 3-26

        SETTLEMENT AGREEMENT EXCLUSION CRITERIA


1.   Equal or more stringent protection is already provided
    by EPA's guidelines and standards under the Act.

2.   The pollutant is present in the effluent discharge
    solely as a result of its presence in the intake water
    to the production .process.

3.   The pollutant i.s not detectable in the effluent within
    the category by approved analytical methods or methods
    representing the state-of-the-art capabilities.  This
    includes cases in which the pollutant is present solely
    as a result of contamination during sampling and analy-
    sis.  (Contamination is determined by the species
    presence in the method and control blanks.)

4.  The pollutant is detected in only a small number of
    sources within the category and is uniquely related to
    only those sources.

5.  The pollutant is present only  in trace amounts  and is
    neither causing nor likely to  cause toxic effects.

6.  The pollutant is present in amounts too  small to be
    effectively reduced by  known technologies.

7.  The pollutant is effectively controlled  by the  tech-
    nologies upon which other effluent limitations  and
    guidelines are based.
                            114

-------
                     Table 3-27

TOXIC ORGANIC POLLUTANTS FOUND IN  UNTREATED EFFLUENT
             FROM ETHANOL PLANTS (ug/1)
Pollutant
benzene
bis phthalate
butyl benzyl phthalate
chloroform
ethylbenzene
methylene chloride
pentachlorophenol ,
phenol
toluene
trichloroethylene
Total
Number
Samples
23
23
23
23
23
23
23
23
23
23
Total
Number
Detects
16
18
6
14
4
20
4
16
20
6
Mean
65
18
13
27
1
30
4
33
10
7 •
Max
1,000
72
220
390
11
99
47
190
94
92
                         115

-------
Pollutants Present Due to Contamination

It is known that during sample collection, automatic composite
samplers were equipped with polyvinyl chloride (Tygon) tubing or
original manufacturer-supplied tubing.  Phthalates are widely
used as plasticizers to ensure that the Tygon tubing remains
soft and flexible . (16,17).  These compounds, added during
manufacturing, have a tendency to migrate to the surface of the
tubing and leach into water passing through the sampler tubing.

Laboratory experiments have been performed to determine if
phthalates and other priority pollutants could be leached from
tubing used on composite samplers (18).  The types of tubing
used in these experiments were clear tubing supplied with the
sampler at the time of purchase.and Tygon S-50-HL, Class VI.
Results of the analyses of the extracts representing the
original and replacement Tygon tubing are summarized in Table
3-28.  The data indicate that both types contain bis phthalate,
and the original tubing leachate also had high concentrations of
phenol.

To verify the actual presence of toxic pollutants in the ethanol
facility effluent streams, an analysis of field and lab contami-
nation was conducted.  This was accomplished by the collection
of method and control blanks.  The results of these analyses are
presented in Table 3-29.  The method and control blank analyses
demonstrate high concentrations (maximum = 190 ug/1) of bis
phthalate; however, phenol was not detected in any of the other
26 samples.  Therefore, bis phthalate is excluded on the basis
of contamination, while phenol is not.
                         \
Two volatile organic compounds were detected as a result of the
analyses of grab samples:  methylene chloride and ethylbenzene.
The volatile nature of these compounds suggests contamination as
a possible source, especially considering the relatively low
concentrations detected in the samples (mean values of 6 ug/1
and 1 ug/1 for methylene chloride and ethylbenzene,
respectively).  Also, these compounds may be found in the
laboratory as solvents,  extraction agents, or aerosol
propellants.  Thus, the presence and/or use of the compounds in
the laboratory may be responsible for sample contamination.
This type of contamination has been previously addressed in
another study (19).   In a review of a set of volatile organic
blank analytical data from this study, inadvertent contamination
was shown to have occurred; the prominent compounds being
raethylene chloride and ethylbenzene.  On the basis of this
study, methylene chloride and ethylbenzene were attributed to
contamination and not selected for regulation.
                                 116

-------
                            Table 3-28

                 TUBING LEACHING ANALYSIS RESULTS
                                         Microqrams/Liter
Component                        Original ISCO             Tygon

Bis (2-ethylhexyl) Phthalate

     Acid Extract                     915                   N.D.
     Base-Neutral Extract           2,070                   885
Phenol
     Acid Extract                  19,650                   N.D.
     Base-Neutral Extract            N.D.                   N.D.
N.D. - Not Detected
                                 117

-------
   g
   CO
   38
   co ptf
   t*JO
CT»  *5

7  S

n  o
0)  ~
3
OiJ
N O
M P<

«r:
is

gs
SpLl
           ii
 Ifl^.

S5S

iSo

ZOA
             ,£S
             Emu
              K!2
             _IUI -I
             ?li
                                                   • OIION
                                                   n
                     o • •«• -oo -o
                                                   •MMM
                                                   •»OO
                     "OO —OWDO'-OOOOOOOOOOOOW'-'-OOOOOO'-
                        _ (-  z  uj3o.u.lu._,  -
                       »ZM  u  z—^-.«~  *"•ZX
-------
!§
  !SA


    tn
   ~s
 _IIU.
 ir1
           01 CO
                                                         8	
                                                     • Mini--
                                                         M
                                                         M
                                                     • •OMB •  •'•
                                                     • ininn •  ••«-«
           oo
                                                     • oo« •  -oo
                                                           ~
             ?2uixiJt-uJOOOQ:n:>ooi-t-'
              i m OOuiiu x SB Eg o±5a aa :	- = --  . -	
           MHMMMMMMZZZZZf>«J_IUJUUIUIUI(IZV»>ltllUll I  r <
           OaOOOOOOUIUUIUIIUUIU.IfeZXXXXX<-iMKZSZZZZ
                          119

-------
   to
   w
   CO
   SHW
   J u
   <3 M

^CJ  ^ti ^ti
0)    O

i  S3

1  I*

I  "I
^ §§
er\  §3
N  Ro
I  Hfe
 0)  OH

»Q  JM
   OCA
   (£&<
8
                                          • m
                                          • o • • .-o
                    OOOOOOOOOONOOOnOOPlOOOVOOOOOOOO
                    B(00Q(0(DOfO(D(D(DI0(0coco(D60C0600nGOflOttOtDflOGOt0GOCD
                    (OCKilCIMCIMCICIMMNMCINnCllMMCINMCimCIMCilNNCil
                      "nn ft in a
                     -IO WM CMN N«


                                     I
                                                         Ul
                                                         s
                                          u
                                                             • u

                                                     !iu     ZHU
                                                     ; o in u M iu M iu

                                            U.L!  z-.K^SSIiSgSS

                                            SlJlpSjjSl&gp*'
                                              >O U Ul I
                                        iSfe!
=1
                                  JIUDZXSS  SS I I  .MMHMK I M

                    ~at  mm      ^-Siuaca & 55>i? ?*1N.C>1.???? "T".1?

                    sl££ggggaS£££ISggSH5lC-Zv*'r
                           120

-------
OiJ
         s
         !l
         si
         ini
         in
IB
3u«-
ZO A


.S6

                 555
                         Q.
               §.
                                 111
                                 2J
                                 S v
                              uuuoz
                   UIZIU   OOO-IZXZiiUJX
                   ^>< .  ^Ilsslssg0-
                 £XU -IK-IIU  _l
                 &xooom_i>:_i
              ! a o -J a. t =J t o v S o


                       _  ! a x
               'i xuiMMKMXaoa
                                          O

                                          §
                        121

-------
Pollutants Detected  in a  Small Number  of  Sources  and  Uniquely
Related to Those Sources

Benzene was found only at plant A01 at concentrations above  its
detection limit  (10  ug/1).  The source of benzene at  this  facil-
ity is the dehydration unit where  it is used as the dehydration
solvent.  (The maximum concentration of .benzene from  the
dehydration column was 1,000 ug/1.)  Since a variety of solvents
are in  use today, permit authorities  should consider the
establishment of a limitation for  benzene if it is used at a
particular facility.

Exclusion of the Remaining Priority Organic Pollutants

Data on treated effluent  are available from three ethanol
facilities (A03, E02, and EOS).  As Table 3-30 shows, the
maximum concentrations of toluene, trichloroethylene,
pentachlorophenol, and butyl benzyl phthalate are below their
detection limit at every  facility  tested.  These  parameters  are
excluded as they are present in the treated effluent at levels
too low to be reduced further by existing treatment
technologies.

Data on Untreated and treated effluent for phenol and chloroform
are presented in Table 3-31.  As this  table shows, phenol was
detected in the treated effluent at only one facility and this
value is suspect since it is higher than the level detected  in
the untreated effluent.  Chloroform was not detected in the
treated effluent at  plant EOS; the presence of chloroform  in the
treated effluent at  plant E02 is suspect as it was not detected
in the influent stream to the treatment system.   The concentra-
tions of these pollutants in the treated effluent are too small
to be quantified by  approved analytical methods.  Therefore,
these pollutants are excluded also.

Exclusion of Priority Metals

Pollutants Present in Amounts Too  Small to be Effectively
Reduced by Known Technologies

The concentrations for priority pollutant metals  found in the
untreated effluent from ethanol facilities are presented in
Table  3-32.  All of these metals  except copper,  nickel, lead,
and zinc are present in the untreated effluent at maximum
concentrations so low that further reductions cannot be
accurately quantified.

Pollutants Detected  at a Small Number of Sources  and Uniquely
Related to Those Sources

The values for copper, nickel, and zinc present in the untreated
effluent for each plant are presented in Table 3-33.  As this

                               122

-------
                   Table  3-30

CONCENTRATIONS OF TOXIC ORGANIC POLLUTANTS FOUND
 IN TREATED EFFLUENT  FROM ETHANOL PLANTS (ug/1)
Pollutant
benzene
chloroform
phenol
toluene
trichloroethylene
Total
Number
Samples
11
11
11
11
11
Total
Number
Detects
3
2
1
2
0
Max
1
42
15
5
0
                        123

-------
*J O
e -H
0) 4J
u u
iJ 3
0) -O

*£
                             o
                             o








J
o
25
Ed
£w
z u
X il
52=. c£
OH
b V3
O <4
O* S
o
3B Z

ftaj
b 04
^ O
HZ
»j as
1^ • »^j
CD U
«C M
U
fl£ H
p*4 21
U
J CO
«c m
u EC
M Oi
C5
Q
*J
o
M
CD













0)
3
l"l
«4
ta

•0

4J
m
0)
H






y
^J
*^n
(0 OI
^^
IS
X 3
* ._
Q 01 g
z ^ z
Jl
i 5 i



^
01 V.
4J OI

4JO
A
01
fH 
fH
IM
IM
CO

•o

*J
(8
Q>

4J
e
a








5?
04 U


vo
^CJ1 ***



f»» N °°
° ° H
•Sfi ™
                   in
                   *-<   CM
                   t-   ®    2
                        ifi    "V
                              in
                   m    CM
                              oo
                                        4J
                                        c
                                        Q>
                                        3
                                        14J
                                        •o
                                        Q)
                                        4J
                                        (Q
                                        C
                                        •o
                                        0)
                                        4J
                                        o
                                        0)
                                        JJ
                                        0)
                                        •c

                                        4J
                                        o


                                        01
                                        5
                                        i
                                        m
                                         o
                                        •H
                                         01
                                         O
                                         a>
                                         a
                                         n
                                         3
                                         01

                                         01
                                         3
                                         01
124

-------
                           Table 3-32

           PRIORITY METALS PRESENT IN UNTREATED ETHANOL
                      PLANT EFFLUENT (ug/1)
lead (total)

mercury (tot

nickel (tota

selenium (tc

silver (tote

thallium (tc

zinc (total)
Compound
total)
.otal)
(total)
.otal)
total)
»tal)
:otal)-
il)
:otal)
>tal) ]
; total)
)tal)
[total)
il)
[chrysotile) (>5 urn)
[fibrous) (>5 urn)
[ chrvsotile-f ibers/
Total
Number
Samples
23
23
23
17
23
23
23
17
23
23
23
23
23
23
3
3
3
Total
Samples
Above
Detection
Limit
6
9
5
12
18
21
1
10
5
11
9
5
4
22
0
0
1
Mean
4
3
2
6
17
342
9
54
<1
71
5
1
11
164


1
Max
10
8
8
17
36
1210
11
189
1
270
43
3
48
590


2
  liter/10E5)

asbestos  (total-fibers/liter/
  10E5)
243
690
                                 125

-------
                           Table  3-33

          PRIORITY POLLUTANT METALS  PRESENT  IN UNTREATED
                   EFFLUENT FROM  ETHANOL  PLANTS
                              Copper
Plant
Code
A01
A08
A06
A07
A10
E02
£08
B09

A01
A03
A06
A07
A10
E02
EOS
E09
Total
No. of
Samples
3
1
3
3
2
2
6
3

3
1
3
3
2
2
6
3
No. Samples
> Detection
Limit
1
1
3
3
2
2
6
3
Nickel
0
1
3
3
0
2
0
2
Mean
(ug/1)
19
950
158
25
559
71
210
762

25*
4
195
46
50*
261
30*
6
Max
(ug/1)
48
950
227
32
1065
71
250
1210

25*
4
264
50
50*
270
30*
8
*Detection Limit.
                                126

-------
           Table 3-33  (Continued)

PRIORITY POLLUTANT METALS PRESENT  IN UNTREATED
         EFFLUENT FROM ETHANOL PLANTS
                     Zinc
Plant
Code
A01
A08
A06
A07
A10
E02
E08
E09
Total
No. of
Samples
3
1
3
3
2
2
6
3
No. Samples
> Detection
Limit
2
1
3
3
2
2
6
3
Mean
(ug/1)
357
270
138
110
114
133
64
153
Max
(ug/1)
590
270
164
128
121
142
119
182
                       127

-------
 table  shows,  relatively  high  levels  of  copper  were  found  in  the
 treated  effluent  only  at plants  A03f  A10,  and  E09.   Likewise,
 only plants A06 and  E02  had relatively  high  levels  of  nickel,
 and  only plant A01 had a relatively  high concentration of zinc.
 For  the  remaining facilities, the levels of  these parameters are
 too  low  to be reduced  further by known  technologies.   Permit
 authorities should consider the  establishment  of a  limitation   .
 for  copper, nickel,  or zinc for  a particular facility  if  these
 parameters are present at levels that can  be treated.

 Exclusion of  the  Remaining Priority  Metals

 The  detection limit  for  lead  varied  from  5 ug/1 to  200 ug/1  for
 different analytical laboratories.  When  analytical values were
 reported such as  <200 ug/1, a value  of  100 ug/1 was used  to
 calculate the mean.   The maximum and mean  concentrations  of  lead
 in the untreated  effluent were 189 and  54, respectively.   This
 parameter was excluded as it  was present  at  levels  too low to
 quantify by approved analytical methods.

 The  Agency  has determined that background levels for total
 asbestos fibers may  be lQ5 to 10? fibers  per liter  of
 sample.   Although the concentration  values for the  samples
 analyzed fall within this background range,  further quantitative
 standards are to  be  promulgated in the  near  future.  Therefore,
 consideration of  this parameter will be deferred until such
 standards are set.

 Exclusion of  Conventional Parameters

 "he fecal coliforms  present in the effluent  from ethanol  plants
 do not originate  in  the  ethanol production process.  The  source
 of this parameter is the. sanitary waste which  is mixed with the
 ethanol plant effluent at some facilities.  Currently fecal
 coliforra levels  are regulated under the NPDES permit program for
 those ethanol plants which treat their  sanitary wastes rather
 than sending  them to municipal treatment systems.   Therefore,
 fecal coliform is excluded since it is  uniquely related to a
 small number of sources within the industry.

 The oil and grease parameter is a measure of the hydrocarbons,
• esters, oils, fats,  waxes, and high-molecular  weight fatty acids
 that are dissolved by extracting the aqueous sample with hexane
 or trichlorotrifluroethane (Freon).   Oil and grease concentra-
 tions ranged from 3 mg/1 to  1,560 mg/1.  An analysis of the con-
 centrations  for  individual plants reveals that the oil and
 grease  contribution from an  ethanol facility is process and
 plant specific.   Therefore, permit authorities should consider
 the establishment of  a  limitation for oil and grease  for
 facilities where this parameter  is determined to be a concern.
                                 128

-------
Exclusion of Nonconventional Parameters

The analytical results for nonconventional metals  in the un-
treated and treated effluent were presented in Tables 3-17 and
3-23, respectively.  Maximum concentrations for six of these
metals were found at levels above 1 ppm in both the treated and
untreated effluent.  These metals include aluminum, calcium,
magnesium, sodium, iron, and phosphorus with maximum values of
1.2, 550, 38.5, 1,060, 5.4, and 63.9 mg/1, respectively, in the
untreated effluent.  There is no data available which suggests
that these metals would be an environmental problem at the
levels detected, therefore they are excluded.

Tables 3-18 and 3-24 presented the results for Appendix C com-
pounds in the untreated and treated effluent.  The only compound
with a maximum concentration greater than 0.05 mg/1 was diethyl
ether with a maximum value of 0.8 mg/1 in the untreated efflu-
ent. Diethyl ether is a common laboratory solvent and may be
present as a contaminant at this low level.  The Appendix C
compounds are excluded as they are present at levels too low to
be reduced further by known technologies.

The analytical results for the remaining nonconventional param-
eters analyzed in the treated and untreated effluent were pre-
sented in Tables 3-19 and 3-25, respectively.  Very high values
of total organic carbon (TOG), chemical oxygen demand (COD),
total dissolved solids (TDS), total solids (TS), and temperature
were measured' for the untreated effluent.  The data show that
secondary biological treatment which reduces 8005 and TSS is
also effective in reducing TOG, COD, TDS, and TS.  Therefore,
since 8005 and TSS have been selected for regulation; TOC,
COD, TDS, and TS are excluded.

The concentration of total phenolics was present above the
detection limit in the untreated effluents; however, its
concentration was below the detection limit for the treated
effluents for every facility tested.  It is therefore excluded
because it is present in the treated effluent at levels too low
to be reduced further by existing treatment technologies.

In addition, the data show a reduction in the temperature of
untreated effluent from an average value of 35°C (maximum of
44°C) to a value of 22°C (maximum of 30°C) for the treated
effluent.  These data do not indicate a need to regulate tem-
perature for treated effluent from the average ethanol facility.
However, permit authorities should consider the establishment of
standards for temperature if this is determined to be a problem
for a particular facility.

While the presence of the pollutants was insignificant in the
facilities studied, they may be present in significant quanti-
ties at any specific facility and perhaps should be considered
by permitting authorities if evidence indicates a concern.
                                129

-------
3.6  AIR EMISSIONS

The Clean Air Act and its amendments created a comprehensive
program to protect and enhance the Nation's air quality and a
regulatory scheme for the control of air pollution.  The
cornerstone of the Act is the development of uniform national
ambient air quality standards (NAAQSK  Responsibility for
limiting emissions to meet the ambient standards lies with the
states. The Act required each State to develop state
implementation plans (SIPs) which provide for implementing,
maintaining, and enforcing the ambient standards.

The Act also requires the United States Environmental Protection
Agency to establish three sets of nationally uniform emission
limitations:  new source performance standards (NSPS), hazardous
pollution emission standards, and motor vehicle emission stan-
dards.  NSPS requires the application of "best demonstrated
technology" to new and modified stationary sources considering
costs and health, energy and environmental impacts.  The Act
allows the States to require more stringent emission limita-
tions than those developed for NSPS.

Part C of the Act, prevention.of significant deterioration of
air quality, provides EPA a means to regulate any pollutant from
any major emitting facility which may adversely affect the
public health and welfare.  A major emitting facility for the
ethanol- for-fuel industry would be any source which releases to
the atmosphere or has the potential to release 227 metric
tons/year (250 tons/year) or more of any pollutant.

In considering the air emissions associated with ethanol
production, available emission data were used to (1) determine
the magnitude of emissions and (2) assess the impact of State
and Federal regulations on the ethanol-for-fuel industry.

A review of existing NSPS reveals that there are no regulations
which specifically address the emissions from the ethanol-for-
fuel industry.  Proposed regulations that will apply to impact
the industry include (1) NSPS for emissions from volatile
organic liquid storage tanks that would have application to the
industry's storage facilities and (2) NSPS for volatile organic
compound (VOC) fugitive emissions in the synthetic organic
chemical manufacturing industry that would specifically deal
with fugitive VOC emissions from the industry.

VOC emissions from storage tanks were estimated and the cost of
compliance to proposed regulations were calculated based on the
work presented in the Background Information Document (BID) for
VOC Emissions from Volatile Organic Liquid Storage Tanks.  Simi-
lar tasks were performed for VOC fugitive emissions based on the
BID for Fugitive Emissions from the Synthetic Organic Chemical
Manufacturing Industry (SOCMI).   It was found that there would

                               130

-------
 be little or no cost to the industry, (or even a savings by
 preventing loss of product) from compliance to these proposed
 standards.

 The assessment of the total projected emissions for ethanol
 plants and their source specific emissions indicates that
 sufficient regulatory activity exists to potentially control
 emissions without initiating additional  regulatory efforts.

 3.6.1  EMISSION SOURCES

 Figure 3-2 illustrates  the major sources of air emissions from a
 typical ethanol-for-fuel facility.   These air emissions consist
 of particulate and volatile organic compounds (VOC), both point
 and fugitive sources.   As  Figure 3-2 shows, the sources for air
 emissions for a particular ethanol  facility depend on the feed-
 stock and by-product processing.  Air emissions from ancillary
 processes, such as steam generation,  are beyond the scope of
 this document and are not  included.

 Regardless of feedstock type or  by-product processing,  all
 ethanol-for-fuel facilities have  air  emissions  from fermenter
 vents as well as condenser vents  on distillation columns  (e.g.,
 the  beer still  and the  dehydration  column).   Volatile organic
 compounds (VOC)  such as ethanol,  by-product fusel oils  (pri-
 marily amyl  alcohols),  low molecular  weight aldehydes
 (acetaldehyde,  and formaldehyde), and dehydration agents
 (gasoline, benzene,  or  hexane) may  be emitted from  these
 sources.   In addition,  fugitive VOC emissions occur throughout
 the  plant at valves, pumps,  flanges,  open-ended  lines,  and
 storage tanks.           !

 By-product processing usually  involves three steps:   (1)  centri-
 fugation  of  the  screened solids from  the beer still,  (2)  concen-
 tration in evaporators,  and  (3) final drying in either  direct-
 contact dryers or  indirect steam heated dryers.  VOC emissions
 occur  from the condenser vents on evaporators.  Indirect  grain
 dryers  are sources of particulates-  and VOC emissions.   Direct-
 contact dryers often use boiler flue  gases  to dry the by-product
 grains; therefore, CO, SOX, and NOX occur in addition to
 particulate  and VOC emissions.

 Table  3-34 summarizes the major sources of air emissions  for an
 ethanol-for-fuel facility which uses grain as a feedstock and
 practices by-product processing.   The utilization of grain
 rather than sugar feedstocks for ethanol  production results in
 the generation of additional particulate  emissions.  In the
 feedstock preparation step, fugitive particulate emissions occur
during the unloading, loading, conveying, rough grinding,
screening, cleaning (with shakers),  and fine milling of the
grain.  If area ventilation is used  to collect these emissions
and then vented to the atmosphere, this becomes  another point
source emission.
                               131

-------
t
•
I-*—

•
*4 	
£^
w
«

J h

DUtilUtioa
ColUKlB




1 1

L
!**"
!

•M
••4
«4
M
u
gp

V




2
|
I
j
9
n- i
w
si 1
• C ** v
rf1*" *
i3

^ k







|
H
1 B
1 d
* S
* ^
HI
o
M
«v«
§
 M
5:
!IU —
M **
ba ««
•
1
^ 2
•
V si .



g
Enxyac
Coiiviril
j i
-g
!«
"i 2.
*£
•k
CO
O
CO

i
•
'


" t
5
5
132

-------
                           Table 3-34

               MAJOR SOURCES OF AIR EMISSIONS FROM
                    AN ETHANOL-FOR-FUEL PLANT*
Grain Handling and Milling

Fermenter Vents
Condenser Vents on
  Distillation Columns,
  Dehydration Columns, and
  Evaporators

Ejector Vent on Flash Cooler
Direct-Contact Dryer Exhaust
Indirect-Contact Dryer Exhaust
Valves, Pump Seals, Open-Ended
  Lines, Flanges, Storage Tanks
Particulates

Volatile Organic
  Compounds
Volatile Organic
  Compounds
Volatile Organic
  Compounds

Particulates, CO, SOXf
  NOX, and Volatile
  Organic Compounds

Particulates, Volatile
  Organic Compounds

Fugitive Volatile Organic
  Compounds
*Based on a facility which uses grain and processes by-product
 grains.
                                133

-------
Finally, grain feedstocks must be cooked to solubilize the
starch portion in preparation for enzyme conversion of the
starch to sugar.  If the cooked grain is flash cooled, VOC
emissions result from steam ejectors used to provide vacuum for
the process.

3.6.2  EMISSION CHARACTERIZATION

To characterize emissions from ethanol-for-fuel plants, a sam-
pling and analysis program was conducted at three facilities:
two plants producing ethanol-for-fuel and one plant producing
beverage alcohol.  The test program was intended to give pre-
liminary information on the type and magnitude of emissions from
the industry.

A multimedia test programi was conducted at plant A03 which
included a screening of all the sources of air emissions.  The
sources tested and the analytical results are discussed below
and presented in Tables 3-35, 3-36, and 3-37.  Data are
presented in standard conditions unless otherwise specified.

Plant A03 has a capacity of 61,000 m3/year (16 x 106 gal-
lons/year); approximately 11,000 m3/year  (3 x 106 gallons/
year) is fuel grade ethanol.  The plant feedstock consists of
starch from a protein extraction unit as well as milled whole
grain.  The cooked mash is cooled in a flash cooler and then
routed to the fermenter.  The remaining process steps  are
similar to those shown in Figure 3-2; benzene is used  as the
dehydration agent.

VOC emissions were sampled at the fermenter vent, beer still
condenser vent, solvent extractor condenser vent, fusel oil
column condenser vent, dehydration column condenser vent, and
the grain dryer cyclone outlet.  The VOC emissions from the
dryer would not be appreciably affected by the cyclone since  it
operates dry.  The results  (Table 3-35) indicate that  the grain
dryer had the greatest VOC emissions with 2.04 kg/hr  (4.50
Ib/hr).  Total VOC emissions were 6.07 kg/hr  (2.75 Ibs/hr) or
0.41 Ibs/ton on a production basis.

An OVA Century  108 hydrogen flame ionization  detector  was used
to measure VOC  emissions.  The detector is sensitive to the
specific type of compound being measured.  Correction  factors
have been determined for several organic  compounds that can be
applied  to determine the correct readings.  However, a
methodology has not been developed to adequately correct
readings for a  mixture of organic compounds.  Therefore,  for
this study, the "worst" case was determined by applying the
largest  correction factor for those  compounds believed to be
present.  In addition, the largest molecular  compound  present
was  used to determine  the mass of the emissions.   These methods,
therefore, are  quite conservative and  actual emissions may be
in the  order of a magnitude less than those calculated.
                               134

-------
      hi
  ^  JS
   0)^ —
   e m
   OJQ
   tfl
                         r-
                         o
                         in
                         1-1
                           •
                         o
                         r»
                         o
                                                              ve
                                                              o
                                                                          o
                                                                           •
                                                                          o
                                                           o
                                                             •
                                                           o
                                                                                     eo t-
                                                                                     voo
                                                           oo
                                       pH ro
                                       (*> O
                                                                       o o
                                                                                     00 00 04
                                                                                     ao coo
                                                                                     in in <-«
                                                                                      •  •  •
                                                                                     o oo
                                                                       o
                                                                       in
                                             4)
                                             4)
                                             (0
                                                                                                              JJ


                                                                                                              4)
                                                                                                              (0
                                                                                                              4)
 I  O


o 10 a
   hi a
> a>
< u
              in
              en
                         en
                                     O
                                     m
                                     in
                                                           r-
                                                           en
                                                                                     o o
                                                                                     o o
                                                                                     eno
                                                                                      %  «
                                                                                     en p»
                                                      o oo
                                                      ooo
                                                                                                              •a

                                                                                                               o
                                                                                     in m c*
                                                                                     in in in
m    u
ro    Z
 I     03
f)    N
      Z
 4).   U
f-4    CO
                                                                       m
                                                                                     in
                                                                                                      o
                                                                                                      en
                                                                                                    O

                                                                                                   •O
                                                                                                    4>
                                                                                                    m
                                                                                                      f)       -Q
                                                                                                      vo
                                                                                                               •o

                                                                                                               m
n ><
                         o
                         o
                         00
                                     o
                                     en
                                     v
                                                                                     in
                                                                                     ci
                                                                                                                    o
                                                                                                                    ve
                                                                                                      in
                                                                                                      in
                                                                                                    09

                                                                                                    0)
                                                                                                    m
JJ


&
hi
4)
JJ



I
                                     JJ


                                     J>
                                  rH hi
                                  •* 4)
                                  jj n
                                  to e

                                  hi rj X
                                  4) C H
                                  4> o
                                  CO CJ
hi
O
JJ
U JJ
« e

z$
M
U hi
   4)
JJ 0)
e e
                    "* e  i
                    o o
                    CO U
                                              c
                                           hi  4)
                                           4>!>
           •rt 4)
           JJ 0}
            u e
            4) 4>
           os-o
Column
Vent
                                                      M4 4)
                                                      O n

                                                      r-l 4) O
                                                      0) -O I
                                                      n c H

                                                      £8
                                                                  e
 o
•H hi    4)
jj 4>    e
 10 m    4>
 hi C    N
•p 4>y e
                                                                                L
                                                                               -»  e
                                                                 38
 Ol hi       4)
 ea>       e
•H m       0

 SSo o c

•Z?£HS
JJ O
en u
                                                                                                4J
                                                                                                 e
4) 4>
c >

r-4 Q X

S,cH
cj o
                                                                                                               •O 0)
                                                                                                               4) U
                                                                                                               U C
                                                                                                               U 4>
                                                                                                               4> iJ
                                                                                                               U 4)
                                                                                                                  4)
                                                                                                                  OS
                                                   135

-------
                            Table 3-36

           PARTICULATE MATTER ANALYSIS AND SAMPLING DATA
              FOR PLANT A03/CYCLONE ON DIRECT-CONTACT
                          BY-PRODUCT DRYER


                                      Particulate      Particulate
                                       Sample  tl        Sample  »2

Average Flue  Gas Velocity (m/s)           14.0            14.1

Average Flue-Gas Temp.  (°C)               98.9            88.3

Stack Pressure  (kPa)                     102              102

Flue Gas Composition

  H20                                     19.2            20.4

  c°2                                      5.0             5.1

  °2                                       6.5             0.5

  CO                                       0                0.6

  N2                                      69.3            73.4

Flue Gas Total Flow (Actual m3)        1,670            1,670
  (ra3/hour)                          63,390          64,240

Flue Gas Grain Loading  (grams/m3)          0.04             0.02

Particulate Flow Rate (kg/hour)            2.8              1.6

Sample Percent Isokinetic               110.9           108.9
                               136

-------



























^
CO
1
CO

0)
«H
•Q
fQ
H







































^^
CO
o
H
Z
«tf
iH OS
^* S
OS OS
O 0
fe
EH
CO CJ
*^ MB?
CO Q
» o
•J5
< On
Z 1
CD
ta
QH
M CJ
X <
O H
z
z o
U CJ
OS CJ
H BJ
M OS
Z M
Q°
38

63 Cd
Q z
M O
X J
OCJ
W ^4
Qcj

OS
3
Cb
tj
o
CO













o
m
c —
O »4
•H .c
MX
to c
"s^
u
o
•
o
V






Q>
4J "^
(0 ^
CO OS £
O SCO
o e
fH *-

0
vo
ON
•»
VO







1 C
c o
33-
co flj S
«J 0) U Q
cj co 4J o
IQ C *••*
£ 0>
PJ O


CO
o
V






•o
10 fl)
•H  jj
(8 O •»* O *"•
*» 0 « C3I
O » CD fH 3
S CO O
o

fH
o
in
VO
V
,






T3
» 0)
rH »^ ^"^
o or>
> se
«J «-
CO

VO
CO
o



14
0 >
C (Q i>4
0 4J Q
c
0) O *»
C CJ 0
0 1 3
•H 4J -O
0 0 O
>sC0 14
cj i4 eu
*f4 i
Q >
CO





fH

&
CO




o
in
o
•
o
V






0
VO
ON
»
VO









CO
o
V







fH
o
in
VO
V








VO
r-
o








CN
=*•

CN
o
CO




CN CN
CN CO 00 CN
^« m in P*
• • . • •
fH O O fH







0000
VO VO VO VO
ON ON ON ON
«*»»•*
VO VO VO VO









fH I*" CO P*
VO O CO CN
CN •"+ CO






m •* ON fH

f"» ON fH ON
VO 







jyh ^| ff* f^*
rl fH fH fH
o o o o
o o o o
o o o o*








fH CN CO ^J"
4t> *• * *

X X X X
o o o o
z z z z




                           JJ    .
                           fl    CN
                           E   O
                           •H   Z
                           3   °
                          5   i
                           W   JC
                              CN
137

-------
The dehydration column and benzene stripping column were also
tested for benzene which is used as a dehydration agent at this
facility.  The benzene emissions detected at the condenser vents
on the stripping column and dehydration column were 0.10 kg/hr
(0.22 lb/hr) and 0.03 kg/hr (0.07 Ib/hr), respectively.

Particulate sampling was conducted on the cyclone which was used
to remove particulate matter from the grain dryer exhaust.  The
inlet to the cyclone was inaccessible and therefore only the
outlet was sampled.  As Table 3-36 indicates, the emissions from
the cyclone outlet averaged 2.2 kg/hr (4.7 lb/hr).  Based on a
conservative removal rate of 80 percent for the cyclone
performance and estimated grain particle size distribution, the
uncontrolled particulate emissions would be approximately 10.a
kg/hr (23.7 lb/hr).  On a production weight basis emissions are
0.73 Ibs/ton.

The flue gases from the gas-fired boiler were used in  the by-
product grain dryer, therefore, the cyclone outlet was also
tested for SOX and NOX.  Table  3-37 presents the results of
this testing.  The SOX concentration  (measured  as SO2)  was
below the detection limit.  Nitrogen oxide concentrations were
below 35 ppm which corresponds  to an emissions  less tnan  ±.»
kg/hr  (4.0 lb/hr).

After testing was completed at  plant A03, two additional  plants
 (A06 and EOS) were selected for testing  to provide further
 information on the magnitude of emissions from  ethanol-for-fuel
plants.  These  facilities  were  tested  for fugitive emission
sources  as  well  as point sources.  A beverage alcohol  plant was
 included in the  test  effort since  these  plants  were determined
 to be  similar to the  ethanol-for-fuel  plants  in volume and
 composition of  air emissions.  Data  obtained  at  plant A03  were
 considered  in determining  which point  sources were the major
 contributors.   The  final  selection  of  sources and types of
 emissions  for plants  A06  and  E06  are summarized in Table  3-38.
 A description  of the  sampling  procedures used at each  site  is
 given  in Appendix A.

 Plant A06.   Plant A06 is  a new grassroots ethanol-for-fuel
 plant.  The processes  employed are similar to those shown  in
 Figure 3-2. Benzene  is also used  in this plant  as the
 dehydration agent.   The plant has a production  capacity of
 11,360 rnVyr (3 x 10° gallons/year).

 Particulate sampling was conducted only on  the  by-product grain
 dryer which was equipped with a cyclone.  The inlet to the
 cyclone was inaccessible and therefore not  sampled.   Particulate
 emissions from this source were 0.15 kg/hr (0.33 lb/hr) which is
 much less than the cyclone emissions for plant  A03.   The differ-
 ence may be due to the difference in sampling methods.  Assuming
 again an 80 percent efficient cyclone, the uncontrolled
 emissions would be approximately 0.75 kg/hr (1.65 lb/hr).
                                138

-------
                           Table 3-38

            1980 EPA SAMPLING PROGRAM/AIR EMISSIONS
                   TESTING OF ETHANOL PLANTS
Plant
Code
A06


Stream Sampled
Stream Ejector Vent
Fermenter Vent
By-Product Dryer
VOC
X
X
X
Particulates


X
                                                     Fugitive
                                                   VOC Emissions
         Cyclone Outlet

        Valves, Pump Seals,
         Flanges, Open-Ended
         Lines, Storage
         Tanks

EOS     Corn Mill Vent -
         Baghouse Outlet

        Centrifuge Vent        X

        Conveyor Vents         X

        Grain Dryer Cyclone    X
         Outlet

        Valves, Pump Seals,
         Flanges, Open Ended
         Lines, Storage
         Tanks
                               139

-------
 VOC  sampling  was  conducted on  the  cooker/cooler at  the  steam
 ejector  discharge,  the  fermenter vent,  and  the  cyclone  exhaust
 on the by-product grain dryer.  VOC  emissions were  greatest  for
 the  dryer,  just as  they were at plant A03.   The average VOC
 emissions  from the  dryer were  9.6  kg/hr (21.1 Ib/hr).   This  is
 much larger than  the  value for plant A03  which  was  2.04 kg/hr.
 The  differences could not be accounted  for  as sampling  error but
 may  be due  to operational differences.  On  a production basis,
 the  uncontrolled  emissions are 0.66  g/kg  (1.32  Ib/ton)  and 8.5
 g/kg (16.9  Ibs/ton),  respectively, for  particulate  and  VOC
 emissions.

 Fugitive VOC  emissions  were measured from flanges,  open ended
 lines, agitator seals,  valves and  pumps.  Over  95 percent of
 these sources were  screened using  a  portable Century  System
 model OVA-108 portable  hydrocarbon detector.  The total VOC
 emissions  were measured at 17.7 kg/day  (39.0 Ibs/day) as shown
 in Table 3-39.  The VOC mass emissions  were estimated from VOC
 emission factors  developed by  the  Agency  on petroleum
 refineries.

 Plant EOS.  Plant EOS is a beverage  alcohol plant with  a ca-
 pacity of  34,065  m^/yr  (9 x 10^ gallons/yr).  The processes
 employed are  basically  the same as those  shown  in Figure 3-2,
 although additional distillation columns  are used to produce
 beverage grade ethanol.

 Particulate sampling  was performed on the corn  mill vent and
 dryer.   The corn  mill is a hammer-type  and  is equipped  with  a
 baghouse.   The inlet  to the baghouse could  not  to be tested;
 therefore,  only the outlet was sampled.   As in  plants A06 and
 A03,  the dryer is equipped with a  cyclone and again, the inlet
 was  inaccessible.

 Particulate results measured 0.55  kg/hr (1.22 Ib/hr) and 0.02
 kg/hr (0.05 Ib/hr)  of particulate  from  the  dryer and corn mill,
 respectively.  Assuming an efficiency of  99 percent, for the
 baghouse and  80 percent  to the cyclone, uncontrolled emissions
.from the dryer and  corn mill are approximately  2.76 kg/hr (6.1
 Ib/hr) and  2  kg/hr  (4.4 Ib/hr), respectively.

 VOC  sampling  was  performed on the  centrifuge, conveyor  vents,
 and  dryer.  VOC emissions were 0.04  and 0.07 kg/hr  (0.02 and
 0.03 Ibs/hr),  respectively, for the  centrifuge  and conveyor
 vents and  41.6 kg/hr  (91.8 Ib/hr)  for the dryer.  This  is larger
 than the other plants measured and may  be due to the presence of
 an oil aerosol in the exhaust stream during testing.  On a pro-
 duction  basis, uncontrolled emissions from  the  dryer are 0.81
 g/kg (1.76  Ib/ton) for particulate  and 12.3 g/kg (24.6 Ib/ton)
 for  VOC  emissions.  VOC emissions would not  be  appreciably
 affected by the cyclone.
                                140

-------
                                                  X
                                                  4J


                                                 Cf-*
W

E
B
              el

              32
               JC
              58
              a *J
              a o
« a

3o

"So

 • d

a*
               o oi
     CM

     e>


     s

     d
                         ^  CM  O




                         fM  f»  -I

                            rt  d  o
           o
            »

           s
                  m

          mo  o  o  o

               -4  d  •«
                             r*  O  O
               a
               • it
              -) 0

              (5 U
     s
          oo
           •  •

          OO
i-t  m
<*»  m  i-t
^5  C?  '^
eoo
a
  v
                                  •8 .
                                                 aw
                                                 ?«
                                                 g>S<
                                                   » 0
                                                 -* C
                                                 OU
a. a
    o

8*5 "S







a e «
                                                 E «



Z v





o
1
co
Flanges



OlA






3
g
cr1
» a oo
> O-l
r-



<-i r*





OS
i

•o
«
•o
&
1 c
1 s.
eu o



0






a
M
CO
Agitator
US 0
«4 U h
h «
01 .o)
£ u a
O.-O 01
2?.°*



,


g
o

a
a
i
2
o
H
4J a a
< 9-0
s u
U4 0
o -fa
u e
u «
c • u

-------
Fugitive emissions were measured at flanges, valvesr pumps, open
ended lines, and agitator seals within the plant.  Approximately
95 percent of these sources were tested.  The total fugitive VOC
emissions were determined as 6.7 kg/day (14.9 Ibs/day) as shown
in Table 3-40.  Mass VOC emissions were estimated using VOC
emission factors developed by the Agency on petroleum
refineries.

3.6.3  NATIONAL EMISSIONS

The total particulate and VOC emissions were estimated for the
current and projected ethanol-for-fuel industry using the data
from plants A03, A06, and A08.  The data from plant A03 include
all major point sources of emissions from a typical ethanol-for-
fuel plant and therefore are used to calculate national point
source emissions.  Fugitive VOC emissions were estimated from an
average of fugitive emissions from plants A06 and EOS:  12.2
kg/day (26.9 Ibs/day) per plant, regardless of production
capacity.

Table 3-41 presents the particulate and VOC emissions calculated
for the current and 1985 projected ethanol-for-fuel industry.
Based on a 1981 estimated production capacity of 6.2 x 105
cubic meters per year (1.6 x 108 gallons per year) from the
industry, national particulate and VOC emissions are approxi-
mately 175 metric tons and 165 metric tons, respectively.  If
all the plants under construction and half of the plants pro-
posed for construction are in operation by 1985, the * projected
production capacity from the resulting 71 plants would be 5.1 x
106 cubic meters per year (1.4 x 109 gallons per year).
Projected particulate and VOC emission for 1985 are 1,500 metric
tons and 1,130 metric tons, respectively.

3.6.4  EMISSION REGULATIONS

A review of existing NSPS reveals that there are no regulations
which specifically address the emissions from the ethanol-for-
fuel industry.  Part C of the Act, prevention of significant
deterioration of air quality, provides EPA a means to regulate
any pollutant from any major emitting facility which may ad-
versely affect the public health and welfare.  A major emitting
facility for the ethanol-for-fuel industry would be any source
which releases to the atmosphere or has the potential to release
227 metric tons/year (250 tons/year) or more of any pollutant.
Based on continuous operation this limit can be expressed as
28.6 kg/hr (63.1 Ibs/hr).  Reviewing the emission data gathered,
only one test, at plant EOS's dryer, resulted in emissions
greater than 28.6 kg/hr and it is suspect.  Otherwise, no data
were available that demonstrate ethanol plants to be major
emitting facilities.
                               142

-------

















o
t*

0)
1-4
,£>
«
H




























OO
O
w
H
25
*S
CD
as
g

CO
H
g
CO
w
OS

S
O
M
03
C/3

0
g
w

H
M
O
£











*?
•c
o a
5C
»4
3|
"S
•JG

2 2> •» «
O O CN vo
S 2 S S
0^
o M «« m
o \oo odd



*
gu
*•< o
a w
.38
J*

C0«
O «A
o tno o o o
• • • • • •
O «CCM «H O — t
•H •><


°id a
oi a
 «-< a. B IS
« f-*O«J § 0) »4
£ 5 11^
tn
i h
S? 33
•
2 tVo
0)
•* «o
i^ ea^
• *w
5S
•o
B -
aw
e «^
•co oo
3 —
I * "
13 .S-i
> •»!
See3
5° .
•5 B 6
41 W-H
oi eo
—1 B£
O W 4J
M*B O

•
g"O ^
h b
«
f u m
9~»ee

5 ««"
^5*2
U4 0
o ••«
U B
4J «
B • 4J
B fl) ^ to
§ I"*™
*<^ 09 U C
0 Sv4 «
•*< B eo
B < • sT
U 2 O v4
O B
•S 8 «! S
V O (•< Q
4J b 41—1
O bt .u ft,
H *
143

-------
                           Table 3-41

         ESTIMATED PARTICULATE AND VOC EMISSIONS FROM THE
         CURRENT AND PROJECTED ETHANOL-FOR-FUEL INDUSTRY
                                    Current .     Projected*
                                    Industry     Industry
                                     (1981)       (1985)

Total Number of Plants                 15            71

Ethanol Capacity (M3/Year)        0,62 x 106     5.1 x 106

Particulate Emissions
  (Metric Tons/Year)                  175         1,500

VOC Emissions (Metric Tons/Year)      165         1,130

  -Point Source                        99           850
  -Fugitive                            66           280
*Includes all plants currently in operation and all plants
 currently under construction as well as 50 percent of the plants
 proposed for construction.
                                144

-------
However, the ethanol-for-fuels industry should consider limiting
the use of benzene as a dehydration agent in order to avoid
emissions of benzene from the condenser vents of the dehydration
columns and separators.  Justifications for limiting the use of
benzene are 1) an alternative dehydration agent that is less
toxic, such as hexane or gasoline, is available and 2) benzene
is listed by EPA as a hazardous air pollutant.

In addition, the Office of Air Quality Planning and Standards
(OAQPS), United States Environmental Protection Agency (EPA) is
presently developing background data for the support of
regulations for volatile organic storage tanks and VOC fugitive
emissions in the synthetic organic chemical manufacturing
industry.  NSPS for emissions from volatile organic liquid  •
storage tanks would have application to the ethanol-for-fuel
industry's storage facilities.  NSPS for VOC fugitive emissions
in the synthetic organic chemical manufacturing industry will
specifically deal with fugitive VOC emissions from the industry.

Although impact of these proposed regulations on the ethanol-
for-fuel industry cannot be quantified until the regulations are
promulgated, the impact may be estimated.*  The background
information document (BID) for VOC Emissions from Volatile
Organic Liquid Storage Tanks  (EPA, a, 1980) evaluated several
alternative methods to reduce or control VOC emissions.
Alternative III, contact internal floating roof with primary
seals only, was the second most cost effective alternative
evaluated and had the lowest  impact on product price, actually
enabling product price to decrease as a result of applying  the
alternative.  Cost impacts were projected assuming this
alternative will be chosen to promulgate NSPS.

Emissions from ethanol storage facilities are not available,
however; the BID for storage tanks developed equations to
estimate VOC emissions.  These equations were used to estimate
both baseline and controlled emissions (EPA, a, 1980).  The
*Impacts of these "proposed" air pollution regulations were
estimated  in 1980.  At the time this document was published  in
1986, the  status of these regulations was as follows:  A)
Standards  regulating volatile organic liquid storage vessels
were proposed on July 23, 1984  (49FR 29698).  The BID was
updated and is listed in Reference 38.   (B) Standards regulating
VOC fugitive emissions were promulgated on October 18, 1983
(48FR 48328).  The BID was updated and is listed  in Reference
39.  For both regulations, the BID alternatives used in the
ethanol-for-fuels cost analyses are not  significantly different
from the alternatives found in the updated BIDs.  Thus, updated
cost analyses were not performed just prior to publication of
this document.

                                145

-------
baseline  emissions  were  estimated  at  0.48  Mg/year  of  VOC for  an
average plant of  7.1  x 104 m3/year.   The controlled
emissions were  estimated at  0.16 Mg/year,  a  reduction in VOC
emissions of 67 percent.  The annualized costs  of  the control
technique per plant is estimated at $86.   The annualized costs
for the entire  industry  in 1985 would be only $7,000  (20).

The BID for VOC Fugitive  Emissions in Synthetic Organic  Chemi-
cals Manufacturing  Industry  (21) evaluated several alternatives
to reduce VOC fugitive emissions.  Alternative  II  was the most
cost effective  alternative evaluated  and also produced the
lowest impact on  product  price, actually allowing  a decrease  in
product price.  This  alternative would  require  leak detection
and repair methods  be implemented.  Leak detection is accom-
plished by use  of a portable VOC detection instrument.   Air near
the potential leak  area  is sampled and  analyzed.   If  VOC emis-
sions are greater than 10,000 ppm, then equipment  repair would
be required.  Cost  impacts were estimated  assuming this  alter-
native is chosen  as a basis  for promulgating NSPS.  The  esti-
mated VOC fugitive  emissions for the  industry in 1985 are 280
Mg/year.  The total annualized costs  without recovery credits
for the industry  to control these emissions are estimated to  be
$80,000;  if recovery credits are included, a net annual  savings
of $22,000 would  result  (20).

There would be  no or very little cost impact of these proposed
standards on the  ethanol-for-fuel  industry.  Furthermore, these
proposed  standards  could actually result in savings to the
industry  by preventing the loss of product.

3.7  SOLID WASTES

The Resource Conservation and Recovery  Act (RCRA) was passed  in
1976xto provide for more uniform solid  waste control.. The pur-
pose of RCRA is three-fold:  (1) regulation of  hazardous waste
management; (2) provide technical and financial  assistance for
the safe  disposal of wastes; and (3)  provide technical and
financial assistance for developing facilities  and plans to
recover energy  and  other resources from discarded materials.

RCRA was  designed with the following  principal  features:
regulation of certain wastes, defined or characterized as
hazardous, are  to be the responsibility of the  federal
government; and regulation of nonhazardous wastes is  to be a
state responsibility, in conformance  with  federal guidelines.
However, under RCRA Section 3006, states are authorized and
encouraged by EPA to develop and carry  out their own  hazardous
waste programs in lieu of a federally administered program.
Authorization for state run programs  must be granted  by  EPA and
is being  initially  administered through an "interim status"
program.  "Final  authorization" will  be possible after Section
3004, Part 264 requirements are promulgated.

                               146

-------
 To determine if industry-specific regulations are needed and
 their subsequent impact,- the prevailing factor is whether the
 waste is considered hazardous or nonhazardous under the Resource
 Conservation and Recovery Act.   If one or more of the solid
 waste streams generated by ethanol-for-fuel facilities are
 considered  to be hazardous,  the  Administrator has the authority
 to "list"  such streams.  When this occurs the generators,
 transporters, and disposers  of these  wastes must comply with all
 appropriate Subtitle C regulations of the Resource Conservation
 and Recovery Act (RCRA 3000  Series).   Wastes which are not
 hazardous  are subject to Subtitle D regulations (RCRA 4000
 Series).

 3.7.1  SOLID WASTE SOURCES

 Data  on  solid waste streams  from ethanol  facilities were
 obtained during a sampling and analysis program.  Details on site
 selection,  waste stream selection,  parameters analyzed,  and test
 methods  are presented in this section.

 It was  determined that none  of the solid  waste streams from
 ethanol-for-fuel plants exhibit  the characteristics of ignita-
 bility,  corrosivity,  reactivity,  or EP toxicity.   Thus the solid
 waste streams would not be considered hazardous under RCRA.
 Since the ethanol production solid  wastes are nonhazardous,  no
 industry-specific- regulations are  required.   Existing federal
 guidelines  which pertain to  nonhazardous  wastes are sufficient
 at this  time.

 The two major solid waste  streams  at  an ethanol-for-fuel  plant
 are the  by-product  stream  and the  biosludge  stream that  results
 from  secondary  treatment of  process wastewater.   Since the  by-
 products have a significant  market  value  they are  most often
 recovered and sold.   Ultimate disposal of  the  biosludge  is
 therefore the only  factor  which will  effect  total  plant
 treatment costs.

 In order to present a  conservative  or  "worst"  case  cost
 analysis, the cost  of  gravity thickening,  aerobic  digestion,
 centrifugation,  and contract hauling were  estimated  since these
methods are capital  intensive.  The production of  biosludge  is a
direct result of  wastewater  treatment and  therefore,  the costs
 associated with  biosludge  treatment and disposal are  included in
 Section 6 under  the cost of direct discharge wastewater treat-
ment options.   In addition,  the economic  impact and  cost/benefit
aspects of biosludge treatment and disposal or management are
discussed in  the  wastewater  treatment section  of this  document.

 In order to evaluate the impact of  solid waste  regulations on
the ethanol-for-fuel industry, an assessment was made of the
 solid waste streams generated by the ethanol production process,
air emission controls, and wastewater treatment.  Solid wastes

                               147

-------
from ancillary processes such as steam generation are beyond the
scope of this document.

Figure 3-3 presents a generic diagram of an ethanol production
process.  One solid waste stream from an ethanol-for-fuel facil-
ity is grain dust collected from particulate controls (e.gef
cyclones) associated with grain milling and by-product drying.
In most cases, particulates collected in grain milling are sent
to the cooker and particulates from by-product drying are recy-
cled to the dryer.  Therefore, these wastes are not considered
further in this analysis.  Other solid waste streams are
stillage from the beer still, if not processed into by-products,
and the processed by-products, if they cannot be sold.

Figure 3-4 presents a diagram of the solid waste streams from
process wastewater treatment.  The solid waste streams are the
treated wastewater if it is land applied and biosludge from
secondary wastewater treatment which may be land applied, land-
filled or hauled away by a contractor.

All of the waste streams identified above are actually potential
waste streams.  It is possible, although not probable, that an
ethanol-for-fuel facility might produce no solid wastes.  This
would occur if the grain dust were recycled, the beer stillage
was either sold wet or processed into by-products which were
then sold, and the process wastewater was indirectly discharged
to a publicly owned treatment works (POTW).  However, an actual
facility will most likely have at least one solid waste stream.

3.7.2  EVALUATION OF SOLID WASTE STREAMS

In 1980, the EPA conducted a test program to characterize the
solid wastes and potential solid wastes from ethanol-for-fuel
facilities.  At the inception of. this test program, there were
five ethanol plants producing ethanol-for-fuel; all five plants
were considered for solid waste sampling.  To increase the data
base, several beverage alcohol plants were also considered for
testing, as this industry was determined from an engineering
standpoint to be analogous to the ethanol-for-fuel  industry in
terms of the characteristics and volume of solid wastes gen-
erated.  Three ethanol-for-fuel and two beverage alcohol
facilities were chosen for sampling in order to include
processes which use different feedstocks and produce various
by-products.

A presampling visit was made to each candidate ethanol facility
to assess the operation of the plant and the accessibility of
the solid waste streams.  The final selection of the sample
points  and sample  type based on the site visits is  summarized  in
Table 3-42 and discussed further below.  A description of the
techniques used to collect the solid samples is provided  in
Appendix A.

                                148

-------
e
o
S r
52
SI










.ol lee ted
w
r
„
u






L









e
0
•
1
b









w

^


j
a
u

J

|
a
1
i
15
0
a
•o
91

i
Jt
U
2
•3
91




09
k




k

1
S
(Sacclmr
L
§
S
1
a.

k
























i




















A
L




















i
<
i

i
(
:
t
t
<
*
i
«*
4
*

i
1
1
1
V
1
4i
1
J

1
!

^



u
:
3
j
?
k

rt
i
K
a
k
»
L u
< 91
1 IW
|H

i
1
^
t
:
i
7
1
a
91
hi
U
en
|
4
1

k



I
||
•« M
•* U
1 '



i
s s
2 a
I "I
1
*
2 •
1 1
V ft*
» *•
i
a
•w
»4
e
09 , a
J
1
|i
£!
i
i
i









PROCESSING
g
t









149

-------
                              •g
                               ca
                         i-l
                         a.
   §
  •rl
  4J
   a
   u
                               u
                               
 
                                                                         60
                                                                        •a
                                                                         o
                                                                         •H
                                                                         «
                sis
                o  Irt
                    CO
                                                      150

-------
 §refyTFVhhiSi 6tha"01 ?lant r°UteS a11 solid waste* associ-
 ated with ethanol  production  to a  centralized feed house where

 thS e?hfnSl ?l??iri ?r°CeSSe; KrS handled'   The solid waste from
 the ethanol facility  cannot be sampled separately; thus, no
 solid waste sampling  was proposed  for this facility.

 Plant A03.  In  1979,  this plant was  sampled for air, water  and
 solid wastes in a  program conducted  by EPA/IERL-Ci.   Solid waste
 samples of by-product grains  and biological sludge were  collect-
 ™°r-me*ai analyses (which  hac3 not  blen  addressed  in the
     — LI study) .
             N° S°*id, WaStSS were samPled  from  this  facility  as
    ^       were similar to those collected from plants A03 and
        0?'  The solid wastes from this plant are routed  to a
        plant and were not selected for sampling.

 Plant Alp.  solid waste streams chosen included by-product con-
 densed cheese whey solubles (CWS) and core samples of land that
 had been subjected to spray irrigation with treated effluent?

 Plant E02.  The types of solid samples that were proposed for
 ?h^ ™.10H ^ fc?X; fa;nity were the by-products produced and
 the wasted biosludge from the bottom of the sludge thickener
 JnH ^'Product samples included the beer still bottom stillage
 and the  condensed molasses solubles.
 f^fh33?!!'  /eedstoc:k 9rain a"d the by-product DDGs were sampled
 from  bulk  storage piles.:  Also, a sample of sludge was collected
 from  the bottom  of the wastewater treatment aera?Jd iSgoon.

             Tl?6re are tw°  solid waste streams from this plant:
 f
 wJJf r?o   grain  and  brProduct Stains.   Both of these stams
 were chosen  for  sampling  and  analysis.
?~ addltu°n t0 the streams  listed  in  Table  3-42,  samples  of  the
feedstocks were  collected to  determine  if the  raw materials  used
bfdetecteTin6,^ tO"iC P°llutants or  contaminants^? mighf
oe detected in the waste streams.

3.7.3  RCRA RELATED ANALYTICAL PARAMETERS AND  TEST METHODS

According to the criteria outlined in RCRA, a  solid waste can  be
^n???-^ hazardous.if it exhibits any of the characteristics
identified as corrosivity, ignitability, reactivity, and  extrac-
tion procedure (EP) toxicity.  At the inception of the solid
waste test program (April 1980), a comparison was made of the
solid waste from ethanol plants and the proposed methods  of
determining corrosivity, ignitability, and reactivity.  Based on
this comparison,  it was ascertained that ethanol-for-f uel solid
                               151

-------
                       Table 3-42
       FACILITIES AND SOLID WASTE STREAMS TESTED
Facility
  A03

  A10

  E02

  EOS

  E09
Solid Waste Stream Tested
Biosludge
Distillers Dried Grains
Condensed Whey Solubles
Core Samples
Beer Still Bottom Stillage
Condensed Molasses Solubles
Biosludge
Biosludge
Distillers Dried Grains
Distillers Dried Grains
                             152

-------
wastes would not be considered  hazardous  using  these  criteria.
Therefore, EP toxicity was the  only hazardous- property  evaluated
further  in this study.

To determine if a  solid waste exhibits  the  characteristic  of  EP
toxicity, RCRA requires that the wastes be  extracted  with
(1) acetic acid and (2) distilled  water and that  these  extracts
(or leachate samples) be analyzed  for compounds listed  as  toxic
contaminants.  Table  3-43 presents a  list of the  toxic  pollu-
tants which must be analyzed to determine EP-toxicityf  as  well
as their detection limits and maximum allowable concentrations.

According to the 19 May 1980 issue of the Federal Register
(Volume  45, Number 98, page 33122) (22),  a  waste  can  be con-
sidered  to exhibit the characteristic of  EP toxicity  if the
extract  from the waste contains any of  the  contaminants listed
in Table 3-43 at a concentration equal  to or greater  than  the
respective value given in that  table.

The results of the test program for RCRA  related  solid  wastes
are presented in Table 3-44.  Of the  14 compounds listed in
Table 3-43, only two  were found at levels above their detection
limits:  barium and chromium.  Barium  levels ranged from 25 to
1,300 ppb and chromium varied from 1  to 35  ppb.  These  levels
are well below those  designated as rendering a'waste  hazardous.
Therefore, the solid  wastes from ethanol-for-fuel facilities
examined in this document are classified  as nonhazardous
according to EP toxicity criteria.

In addition to leachate analysis,  the'solid waste samples  were
also analyzed to determine  if the  solid wastes, rather  than
contamination, were the source  of  any toxic pollutant found in
the leachate analyses.  The results  from  the solid digestion
analyses are presented in Appendix D.   Since no toxic pollutants
were detected above the maximum allowable concentrations in the
leachate analyses, no further analysis  of the solid digestion
data  is  required at this time.

Other analytical parameters which  were  evaluated  are  presented
in Table 3-45.  The analytical  methods  used for all the
parameters  identified are discussed  in  Appendix B. The results
for the  leachate analysis and the  solid digestion analyses are
•presented  in Appendix D.  The Agency  has  determined that none of
these other pollutants were present  at  levels which are
considered  to be hazardous  at this time.

All of  the  RCRA related parameters (Table 3-43) as well as the
other parameters  (Table 3-45) were tested for on  samples of the
ethanol  plant  feedstocks.   The  results  of the leachate  analysis
and the  solid digestion analyses are  presented  in Appendix D.
None  of  the pollutants were  detected  at levels  which  are
considered  to be hazardous  at this time.

                                153

-------
                            Table 3-43
            POLLUTANT PARAMETERS ANALYZED TO DETERMINE
                         RCRA EP-TOXICITY
Toxic Metals

Arsenic

Barium

Cadmium

Chromium

Lead
  %
Mercury

Selenium

Silver



Pesticides

2-4 D

2,4,5 TP Silvex

BHC (Lindane)-Gamma

Endrin

Methoxychlor

Toxaphene
Detection Limit (ppb)
   Max imum
  Allowable
Concentration
    (ppb)l	
^Source:
          p. 33122 (22).
2
1
42
5
2
0.2
2
10
\
0.8
0.3
0.2
2
2
100
Federal Register, Volume 45,
5,000
100,000
1,000
5,000
5,000
200
1,000
5,000

10,000
1,000
400
. 20
10,000
500
Number 9
                                 154

-------




















rr
1
m

l)
S
H





















l»
^C
n
D
CO
CO


1
I*
. -s( 00
aojal « t ^| *cf ^* in "•* •<
ab.S1 O o S
c ol i ! S 5- ' i
\jjrf.s3 o o rf ^ S
f» CM CO 01 <
<^ OJ |H
S _
.J £
M a-4 U
HsS
3 a u-3
z a a
ene
£ j
3
eg n rt f-i m *4 p-t m ut



!?!,«,
sJ s


A§
(4 C9-4 4J
"S'aSJ
Zw^

O r- O O -• -1




i£
i-! a
oci
H

c>j tn K « m m


1 Botton Stillage
•ri
1*4
CO
u
01
aa
09
e

•§
f-4
a
o
-4
a
i
0)
14
a u
4) CO
«M
1
3
so
s
o
u
1 Bottom Stillage
s Dried Grains
i*4 4)
CO r*
(4 M
a a
a
«-i
X
i
"8
a
e
9)
C
3
Molasses Soluble,
"S
a
e
9)
•a
e
3

so
"§
a
O
pa
a
9)
t~<
a.
8
a
en
u
3
155

-------
                            Table 3-45
      ANALYTICAL PARAMETERS ANALYZED FOR SOLID WASTE TESTING
Metals

Aluminum
Beryllium
Bismuth
Boron
Calcium
Cobalt
Copper
Gold
Indium
Iron
Lithium
Magnesium
Manganese
Molybdenum
 Detection
Limit (ppb)

    50
     2
   250
    45
    40
    30
     5
    48
   280
     8
     2
   500
     6
    10
Metals

Nickel
Phosphorus
Platinum
Potassium
Silicon
Sodium
Strontium
Tellurium
Tin
Titanium
Uranium
Vanadium
Wolfram
Yttrium
Zinc
 Detection
Limit (ppb)

    15
   180
   600  .
    40
    16
    11
     2
   520
   600
    25
   320
    15
    90
     9
    15
Anions*
Chloride
Nitrate
Sulfate
Total Organic Carbon
                Detection Limit (ppb)
                        600
                      1,000
*Distilled water leachate samples were not analyzed for anions,
                                156

-------
                             SECTION  4

           WASTEWATER TREATMENT AND  CONTROL TECHNOLOGY


 4.1  BACKGROUND

 Applicable technologies effective in reducing or eliminating
 pollutants present  in wastewater from ethanol-for-fuel plants
 include in-plant source control methods for wastewater reduc-
 tion, such as plant management practices and production process
 modifications; preliminary, primary, secondary, and tertiary
 wastewater treatment technologies; disinfection and sludge
 handling.  The pollutant parameters of concern are 8005, TSS,
 and pH as discussed in Section 3.5.

 The quantity and characteristics of untreated effluent generated
 by beverage alcohol.facilities are not significantly different
 from that generated by ethanol-for-fuel facilities.  This is
 strong evidence that the control and treatment technologies used
 by beverage alcohol plants are not only applicable to ethanol-
 for-fuel. facilities, but should also result in similar perform-
 ance and reduction of pollutant parameters.  Hence, treatability
 data from both industries are presented in this section.

 A survey of the ethanol-for-fuel industry in 1981, which in-
 cludes data on 15 facilities, reveals that 12 facilities (80
 percent) were indirect dischargers (or facilities discharging
 into publicly owned treatment works).  This high percentage is
 attributed to the fact that most existing ethanol-for-fuel
 facilities are small; two-thirds of existing ethanol-for-fuel
 plants have capacities less than three million gallons of
 ethanol per year. Combining these data with the available data
 from 16 beverage alcohol plants, the indirect dischargers then
 comprise about 50 percent of the industry.  All of the beverage
 alcohol plants considered have capacities larger than three
million gallons of ethanol per year.   In addition to size, plant
 location also influences whether a particular facility is a
direct or indirect discharger.  In 1981 there were three large
 facilities, with capacities greater than 15 million gallons per
year, located in urban areas which were also indirect dis-
chargers.

 In regard  to level of technology practiced, all beverage alcohol
and ethanol-for-fuel plants which were direct dischargers use
secondary  biological treatment systems.   Many of these treatment
systems also incorporated some form of preliminary treatment


                               157

-------
(e.g., neutralization, bar screening)  and/or primary treatment
 e.g.  coarse screens, primary sedimentation).   In addition,  60
percent of the indirect dischargers from the ethanol-for-f uel
industry (44 percent of the indirect dischargers from both
ethanol industries) use secondary biological treatment before
discharging their effluent to a municipal treatment plant.

The most common methods of secondary treatment in use at ethanol
plants were aerated lagoons, stabilization or °5ldajlon P°£d^'
activated sludge systems, trickling filters, and rotating bio-
logical contactors (in that order).  Data were1availa^d°" the
trlatability of BOD5 and TSS from 12 ethanol Pja^ secondary
treatment systems; these data are summarized in Table 4 1.  As
this table shows, BODs reduction varies from 87. b to ye./
percent and TSS reduction varies from 25.2 to 96.3 percent. The
low TSS Deduction associated with plant E18 is due to a problem
with algal growth  in  the stabilization pond.
No  tertiary treatment was  in use at ethanol-for-f uel
however, one beverage alcohol plant had a polishing pond and
another used an  air  flotation unit.  No data was available which
quantifies treatability of BOD5 or TSS from these tertiary
methods of treatment when  used on ethanol plant wastewaters.

Finally, all plants  which  combine their domestic wastes with
process wastes  (25 percent of the plants surveyed) use
chlorination for disinfection.  The ef fectiveness of  dis-
infection by chlorination  for bacteria  (e.g.,  fecal col i form)  is
nearly 100 percent  if proper dosage rates and  sufficient contact
times are used.

4.2  IN-PLANT  SOURCE CONTROL FOR WASTEWATER REDUCTION
 The generation of wastewater from facilities that
 ethaLl via fermentation can vary from as much as  f-5 gallons of
 wastewater per gallon of ethanol for plant A06 to  33.7 gallons
 of wastewater per gallon of ethanol for plant E09  (see Table
 6-sT?  The widfrange in these ratios is a result  of the former
 plant's efforts to minimize wastewater generation  by improved
 plant management practices and production process  changes.
 These practices can only be effective in con3 unction with
 increased management awareness of the importance of in-plant
 control.

 4.2.1  PLANT MANAGEMENT PRACTICES

 The primary plant management practices for wastewater reduction
 inllude proper spill disposal, washwater control,  and water con-
 servation.
                                 158

-------
                          Table 4-1
BODs AND TSS REDUCTION ACHIEVED BY ETHANOL PLANT
WASTEWATER TREATMENT SYSTEMS
Plant
Code
A03
E02
EOS
E06
E07
EOS
E12
E13
E15
E17
E18
E21

Wastewater Percent BODs
Treatment System Reduction
Activated Sludge
Aerated Lagoon with
Stabilization Pond
Aerated Lagoon with
Stabilization Pond
Activated Sludge with
Stabilization Pond
Aerated Lagoon with
Rotating Biological
Contactor
Aerated Lagoon with
Rotating Biological
Contactor
Trickling Filter with
Stabilization Pond
i
Aerated Lagoon with
Stabilization Pond
Aerated Lagoon with
Stabilization Pond
Aerated Lagoon with
Trickling Filter
Aerated Lagoon with
Stabilization Pond
Activated Sludge
Averaae of Treatment
98.7
87.6
96.5
91.9
93.3
97.0
96.4
94.5
98.3
97.2
98.2
98.6
95.7
Percent TSS
Reduction
95.0
55.6
77.5
82.9
73.8
73.0
92.9
82.5
84.4
76.1
25.2
96.3
80.7*
          Systems'  Performance







*Average does not include value for plant E18,
                                159

-------
Spill Disposal

Spills from ethanol-for-fuel facilities may result from tank
overflows, the loss of heating or cooling in the distillation
columns, pumping equipment malfunctions, or operator error.  The
containment and disposal of these spills can be facilitated by
the use of a process centralized sump or a spill lagoon*

Plant A01 has a centrally located sump in its distillation
building.  The spill disposal system has been designed such
that, depending on the liquid in the sump, the spill can be
recycled to the distillation columns for ethanol recovery or
pumped to the wastewater treatment facility.

Spill lagoons, such as the ones maintained by plant E02 and E15,
function in a similar fashion, but they are larger and not
designed to recycle the spilled liquid back to the ethanol pro-
duction process.  The spill lagoon liquid is gradually added to
the wastewater treatment system to prevent upsets in the second-
ary biological treatment operation which may result from a fluc-
tuating wastewater strength.

Washwater Control

The quantity of washwater generated at an ethanol-for-fuel
facility is less than that produced by beverage alcohol plants
because of the lower purity requirements of the former industry.
However, certain'washes, such as those for the fermenters, are
still required to avoid bacterial contamination.  Common
in-plant controls which may be employed to reduce waste
generation include:

     1.   Install central cleanup systems such as clean-in-place
(CIP) units (valved or triggered hoses).  These systems generate
a controlled-pressure supply of hot or warm water containing a
detergent and reportedly clean better with less water  (ESE,
1974).  Plants E09 and ElO use CIP units to clean the  fermenters
and feedstock delivery trucks, respectively.

     2.   Eliminate practices of unnecessary washwater use.
Many plants operate water valves wide open, regardless of  actual
need. The installation of ball valves in water lines after globe
valves  reduces water usage since the ball valve functions  as a
volume  adjustment and the globe valve as an on/off controller.

Water Conservation

Techniques that  are available for wastewater reduction by  water
conservation  include:

      1.   Install automatic  shutoff valves.  Water hoses equip-
ped with  these valves can save up to 60 gallons per minute when
employees forget to shut off hoses  (14).

                                160

-------
      2.    Install low-volume, high-pressure systems on all water
 sprays which cannot be eliminated.

      3.    Recirculate water for reuse in feedstock preparation
 (e.g., washing, mashing)  or, if applicable, extractive distil-
 lation.

      4.    Parallel product purity with water purity by introduc-
 ing the  fresh water in the latter stages of production and then
 reusing  it in earlier stages of the process.  This technique
 reduces  the input of fresh water.

      5.    Recycle of noncontact waters from mash cooling and the
 distillation column condenser,  and any noncontact streams of
 suitable quality for other in-plant uses.

 4.2.2  BEST MANAGEMENT PRACTICES

 Plant  management practices can  be required  in NPDES permits  as
 Best Management Practices  (BMPs).   BMPs  are broad and  may
 include  processes,  procedures,  human actions,  or construction
 requirements.   Pursuant to Sections 304  and 402  of the Clean
 Water  Act,  BMPs may be incorporated into permit  conditions
 supplemental  to numerical  effluent llimits.

 BMPs in  NPDES  Permits

 BMPs are placed in  permits  in two  basic  ways:  BMP plans  and
 site-  or pollution-specific  BMPs.   Site-specific BMPs  may be
 imposed as specific  conditions of  the  BMP plan or as independent
 provisions of  the permit.   BMP plans are usually kept  on-site
 and made available  to  the permitting authority on request.   The
 normal compliance schedule  is to  require preparation of  the  plan
 within six months, and implementation  within twelve months,  of
 permit issuance.  Nine specific requirements have been
 identified as a basis  for developing BMP plans in the  NPDES
 program.  Site-specific or pollutant-specific BMPs  are left  to
the discretion  of the permit writer and  are highly dependent
upon a careful  review  of the circumstances  at a  particular
 facility.  The minimum requirements of a BMP plan are  presented
below.

Minimum Requirements of a BMP Plan

1.  General Requirements

    o  Name and location of facility
    o  Statement of BMP policy and objective
    o  Review by plant manager
                               161

-------
2.  Specific Requirements

    o  BMP committee
    o  Risk identification and asssessment
    o  Reporting of BMP incidents
    o  Materials compatibility
    o  Good housekeeping
    o  Preventive maintenance
    o  Inspections and records
    o  Security
    o  Employee training.

BMP Committee

The BMP committee is that group of individuals within the plant
organization which is responsible for developing the BMP plan
and assisting the plant management in its implementation,
maintenance, and updating.  Thus, the committee's functions are
similar to those of a plant fire prevention or safety committee.
Plant management, not the committee, has overall responsibility
and accountability for the quality of the BMP plan.

The scope of activities and responsibilities of the BMP
committee should include all aspects of the facility's BMP plan,
such as identification of toxic and hazardous materials
addressed in the plan; identification of potential spill
sources; BMP inspections and records procedures, review of
environmental incidents to determine and implement necessary
changes to the  BMP plan; coordination of incident notification,
response, and clean-up procedures; establishment of BMP training
programs for plant personnel;  and aiding interdepartmental
coordination in carrying out the BMP plan.

Risk Identification and Assessment

The areas of the plant subject to BMP requirements should be
identified by the  BMP committee, plant  engineering group,
environmental engineer, or others in the plant.  Each such area
should be  examined  for the potential risks  of discharges  to
receiving waters of toxic pollutants or hazardous substances
from ancillary  sources.  Any  existing physical means  (dikes,
diversion ditches, etc.) of controlling such discharges also
should be  identified.

A hazardous  substances and  toxic chemicals  inventory  (materials
inventory) should  be developed as part  of  the risk
identification  and assessment.  The  details of  the materials
inventory  should be proportionate to the quantity of  toxic
pollutants and  hazardous  substances  on  site and  their potential
for reaching  the receiving  waters.
                               162

-------
Reporting of BMP Incidents

A BMP incident reporting system is used to keep records of
incidents such as spills, leaks, runoff, and other improper
discharges for the purpose of minimizing recurrence, expediting
mitigation or cleanup activities, and complying with legal
requirements.  Reporting procedures defined by the BMP committee
should include:  notification of a discharge to appropriate
plant personnel to begin immediate action; formal written
reports for review and evaluation by management of the BMP
incident and revisions to the BMP plan; and notification, as
required by law, of government and environmental agencies.

Materials Compatibility

Materials compatibility includes the consideration of:
compatibility of the chemicals being stored with the container
materials; compatibility of different chemicals upon mixing in a
container; and compatibility of the container with its
environment.  The BMP plan should provide procedures to address
these three aspects in the design and operation of the equipment
used for the storage or transfer of toxic and hazardous
materials.

Incompatible materials can cause equipment failure resulting
from currosion, fire, or explosion.  Equipment failure can be
prevented by ensuring that the hazardous substances or toxic
pollutants are compatible with the container contents and the
surrounding environment.

Good Housekeeping

Good housekeeping is the maintenance of a clean, orderly work
environment and contributes to the overall facility pollution
control effort.  Periodic training of employees in housekeeping
techniques for those plant areas where the potential exists for
BMP incidents reduces the possibility of mishandling of
chemicals or equipment.

Examples of good housekeeping include neat and orderly storaage
of bags, drums, and piles of chemicals; prompt cleanup of
spilled liquids to prevent significant runoff to surface waters;
sweeping, vacuuming, or other cleanup of accumulations of dry
chemicals as necessary to prevent them from reaching receiving
waters; and provision for storage of containers or drums to keep
them from protruding into open walkways or pathways.

Preventive Maintenance

An effective preventive maintenance (PM) program is important to
prevent environmental incidents.  A PM program involves
inspection and testing of plant equipment and systems to uncover


                               163

-------
conditions that could cause breakdowns or failures, with
resultant significant discharges of chemicals to surface waters.
The program should prevent breakdowns and failures by adjust-
ment, repair, or replacement of items.

A PM program should include a suitable records system for
scheduling tests and inspections, recording test results, and
facilitating corrective action.  Most plants have PM programs
that provide a degree of environmental protection.  A BMP plan
should not require the development of a redundant PM program.
Instead, the plan should reinforce the objective to have
qualified plant personnel (e.g., BMP committee, maintenance
foreman, or environmental engineer) evaluate the existing plant
PM program and recommend to management those changes, if any,
needed to address BMP requirements.

A good PM program includes identification of equipment or
systems to which the PM program should apply; periodic
inspections or tests of identified equipment and systems;
appropriate adjustment, repair, or replacement of items; and
maintenance of complete PM records on the applicable equipment
and systems.

Inspections and Records

An inspection and records system detects and documents actual or
potential BMP incidents.  The BMP plan should include written
inspection procedures and optimum intervals between inspections.
Records to show the completion date and results of each
inspection should be signed by the appropriate supervisor and
maintained for a period of three years.  A tracking or follow-up
procedure should be instituted to ensure that adequate response
and corrective action have been taken.  The record keeping
portion of this system can be combined with the existing spill
reporting system in the plant.

The inspection and records system should include those equipment
and plant areas having the potential for significant discharges.
To determine the inspection frequency and inspection procedures,
experienced personnel should evaluate the causes of previous
incidents, the likelihood of future incidents, and assess the
probable risks for incident occurrence or recurrence.  Con-
sideration should be given to the nature of chemicals handled,
materisls of construction, and site-specific factors including
age, inspection techniques, and cost effectiveness of BMPs
employed.

Security

A security system prevents accidental or intentional entry to a
plant which might result in vandalism, theft, sabotage, or other
improper or illegal use of plant facilities that possibly could

                               164

-------
cause a BMP  incident.  Most  plants  have  security  systems  to
prevent unauthorized entry.

The BMP plan should describe those  portions of  the  existing
security system and any  improvements  that  are necessary to
ensure toxic chemicals are not discharged  to receiving waters  in
significant  quantities as a  result  of unauthorized  entry.  Doc-
umentation of the security system may require separate filing
from the BMP plan to prevent unauthorized  individuals from
gaining access to sensitive or confidential information.

Employee Training

Employee training programs should install  in personnel, at all
levels of responsibility, a complete understanding  of the BMP
plan.  Training should address the  processes and materials on
the plant site, the safety  hazards, the practices  for
preventing discharges, and the procedures  for responding
properly and rapidly to  toxic and hazardous materials incidents.

Meetings should be conducted at least annually  to assure
adequate understanding of the objectives of the BMP plan and the
individual responsiblities of each  employee.  Typically, these
could be a part of routine employee meetings for safety or fire
protection.  Such meetings should highlight previous spill
events or failures, malfunctioning  equipment, and new or
modified BMPs.

Training sessions should review the BMP plan and associated
procedures.  Just as fire drills are used  to improve an
employee's reaction to a; fire emergency, spill  or environmental
incident drills may serve to improve the employee's reactions to
BMP-related  incidents.   Plants are  encouraged to conduct spill
drills on a quarterly or semi-annual basis.  Spill  or incident
drills serve to evaluate the employee's knowledge of BMP-related
procedures and are a fundamental part of employee training.

Site-Specific or Pollutant-Specific BMPs

Site-specific and pollutant-specific BMPs  are those designed to
address conditions peculiar to a facility  or pollutant.  The
need for specific BMPs at a facility often will be discovered in
conjunction with other permit-related activities, such as
compliance inspections.  Poor housekeeping or a history of
spills, for example, indicate a need for site-specific BMPs to
supplement the quantitative effluent limits on specific
pollutants in the permit.  These "situation-specific" BMPs may
be conventional, such as secondary containment around a storage
tank, or innovative, such as siting containers so that a spill
caused by a careless forklift operator will not flow into the
river.  Other examples of site-specific BMPs are contained in
recent NPDES permits.

                               165

-------
4.2.3  PRODUCTION PROCESS MODIFICATIONS

A wide range of values for the quantity of wastewater generated
per gallon of ethanol produced is not only linked to plant
management practices, but also to equipment selection.  The
following process changes can be implemented to reduce
wastewater generation:

     1.   The addition of instrumentation for the automatic con-
trol of evaporator operation at optimum levels of liquid/solid
separation.  Evaporator performance below the optimum operating
conditions can increase entrainment by stillage flashing upon
entering the evaporator or foaming.  Entrained solids signifi-
cantly increase the BOD and TSS of the evaporator condensate
sent to wastewater treatment.

     2.   The replacement of barometric condenser systems used
in mash cookers, mash coolers, and evaporators with surface
(noncontact) condensers.  The cooling water added to the
condensate increases the hydraulic load requirements of the
wastewater treatment system.  The barometric condensate can
amount to as much as 28 percent of the total BOD load (14).

     3.   The use of reboilers rather than live steam for
heating the distillation columns can reduce wastewaters from the
column bottoms by 20 to 30 percent (14).

     4.   The removal of the purifying columns from beverage
plants planning to convert to ethanol-for-fuel production
indirectly reduces wastewatergenerated by lowering steam and
cooling requirements.

4.3  PRELIMINARY TREATMENT TECHNOLOGIES

In order to allow downstream operations to perform effectively,
the influent to the wastewater treatment system is often
subjected to preliminary treatment such as bar screening,
comminuting, equalization, and neutralization.  The use of bar
screens and communitors protects pumps and other equipment
downstream from damage by large solids.  An equalization basin
provides the necessary flow rate control, while a neutralization
system provides pH control.  Biological treatment tolerates only
a small pH range; thus, control of the influent stream  is
required to prevent pH shock.

4.3.1  BAR SCREENING

Screening, as a method for removing large suspended particles,
is commonly used  in wastewater treatment plants.  The ethanol-
for-fuel plants using screening are A01, A03, and A07.  Bar
screens or bar  racks are considered to be a preliminary treat-


                                166

-------
ment option and can be used to protect plant equipment against
large solids which can cause physical damage.  A bar screen is
made of vertical steel bars spaced at equal intervals across a
channel through which the wastewater flows.  Openings between
the bars range from 50 to 150 mm  (two to six inches), thus
preventing large, heavy objects from entering the treatment
plant and damaging pumps or other downstream equipment (23).
The screen is automatically cleaned by a traveling rake. Bar
screens are used ahead of raw wastewater pumps, flow meters,
grit chambers, and primary sedimentation tanks.

4.3.2  COMMINUTORS

Comminutors are cutting devices that cut influent waste
materials to six to nineteen mm in length  (0.25 to 0.75 inch)
without removing material from the flow (23).  They serve the
same basic function as bar screens by reducing the size of
solids entering the treatment plant.  These devices are
currently being used by several beverage alcohol plants.

4.3.3  GRIT REMOVAL

Wastewater grit materials are characterized as nonbiodegradable,
having a subsiding velocity substantially greater than that of
organic biodegradable solids, and they are generally discrete
rather than flocculent in nature.  Materials falling into these
categories are particles of sand, gravel, and other minute
pieces of mineral matter.  Grit is removed from a wastewater
system to protect moving mechanical equipment from abrasion and
abnormal wear; reduce conduit clogging; and prevent loading of
treatment works with inert matter that may interfere with the
operation (e.g., siltation of anaerobic digestors or aeration
tanks).  Grit removal devices are currently classified as either
horizontal flow or aerated.

The quantities of grit removed via mechanical cleaning in a
horizontal flow device or in the hoppers of an aeration device
can vary greatly.  Values separated range from 3.1 m3 per
million liters to 225 m3 per million liters for municipal
treatment systems.  Aeration tank grit removal devices can
achieve, with proper adjustment, greater than 99 percent grit
removal.

The choice of grit removal method is usually determined from
factors such as head loss requirements, space requirements,
types of equipment used elsewhere in the plant, and the costs of
each of the three alternatives.  Aerated grit removal offers the
advantages of minimal head loss through the grit chamber, low
biodegradable solids removal, and simultaneous grease removal by
surface skimming.  In addition, the wastewater may undergo some
BOD5 reduction because of the contact with air.  Aerated grit
                               167

-------
chambers can also be used for chemical  addition prior  to
settling (23).

The grit that is  stored  in hoppers  is usually disposed of by
truck  hauling to  a landfill for large installations.   For
individual  wastewater treatment systems encountered at ethanol
plants,  the amount of this material which would be collected is
relatively  small  compared to other  solid waste  streams.  Only
one plant,  EOS, was reported to use grit removal as part of a
primary  treatment scenario.

4.3.4  EQUALIZATION  ' '

A common problem  in ethanol-for-fuel wastewater treatment plants
is rapidly  changing influent wastewater flow rate and  BODs
concentration.  A decrease in flow  rate can reduce settler
overflow rates while an  increase in flow rate can decrease
solids removal efficiency.   Changes in  influent wastewater
concentration can result in process overloadings and ultimately
bring about  decreases in effluent  quality.  Equalization acts
to control  fluctuation in both flow rate and concentration.

An equalization basin is simply a basin to which the influent
wastewater  is pumped at  varying  flow rates; wastewater is simul-
taneously pumped  out of  the  equalization basin  at a constant (or
near constant) flow rate and  fed  to the downstream treatment
units.   Wastewater in the equalization  basin is mixed, either by
mechanical mixing  or by  air sparging.   The mixing results in
less variation in the BODs concentration of the wastewater
pumped from the equalization  basin  and  prevents  solids from
settling and  accumulating on  the  bottom of the  basin.

Typical  schematic  flow diagrams of  equalization basins are shown
in Figure 4-1.  As  illustrated by the figure, there are basi-
cally two different equalization  flow schemes:   in-line equali-
zation and side-line  equalization (24).   In-line equalization
has been found to  provide the greatest  flow rate and concen-
tration damping, as  well  as minimizing the effects of, toxic
shock loads and providing some pH stabilization.  In-line
equalization  is practiced at ethanol-for-fuel plant A01 as well .
as beverage alcohol  plants E04 and  E21.   Thus,  in-line
equalization  is recommended when biological treatment is being
used (24).

4.3.5  NEUTRALIZATION

In a study of the  beverage alcohol  industry. Environmental
Science  Engineering  found that the pH of the combined process
effluent may vary  from a  value of four to eleven over a 24-hour
period (13).  Also, the data presented in Section 3 of this
document reveal a  pH  fluctuation of three to 13 for raw
wastewaters from this industry.  Generally,  Publicly Owned

                                168

-------
Stw
U4
                                                                             s
                                                                                    «CJ<

                                                                                    a)
                                                                                    M
                                                                                    d
                                                                                    bO
                                                                                       i
                                                                                       j
                                                                                       fe
                                                                                       u
                                                                                       M
                                                                                       H
                                                                                       W
                                                                                       U
                                                                                       CO
                                                                                            cs
                                                                                            (U
                                                                                            o
                                                                                            o
                                                                                            03
                                        169

-------
Treatment Works (POTWs) require any wastewater being discharged
into their system to have a pH between 6.0 and 9.0.  The optimum
pH for biological wastewater treatment is in the range of 6.5 to
8.5 (25).  Thus, the effluent from ethanol-for-fuel plants will
require pH control whether the wastewater is discharged to a
POTW or to an on-site biological treatment system.

The conventional name for pH adjustment in wastewater treatment
applications is neutralization.  In the ethanol-for-fuel and
beverage alcohol industries, a common practice is to combine
alkaline washwaters with acidic process wastewater.  Plants A01,
A03, and A07 use this method of neutralization.  Occasionally,
further neutralization consisting-of acid or base addition is
required when sufficient quantities of alkaline or acidic
wastewater are not available.  •

A variety of alkaline  substances can be used.  Lime is usually
the least expensive alkali source, although both sodium
hydroxide (NaOH) and sodium carbonate  (Na2CO3) have been
used.  Pebble quicklime, which is simply high calcium quicklime
in pebble form, is easier to handle and creates fewer dust
problems than other forms of lime (24).  Quicklime is fed into a
lime slaking tank, where the solid quicklime  (CaO) is reacted
with water to form a calcium hydrate (Ca(OH)2) slurry.  The
lime slurry is then pumped  into a holding tank, where it  is
mixed to maintain the  lime  in suspension and  is fed by a
metering pump into the neutralization  reaction tank.

In general, either sulfuric acid or hydrochloric  acid is  used  as
an acid  for neutralization.  Both acids are handled as liquids
from delivery to application.  The acid is  stored  on-site in a
storage  tank and pumped to  the neutralization reaction tank.

A neutralization reaction tank is used to provide  for proper
mixing  and contact time  for the complete  neutralization of the
wastewater.  Wastewater enters the tank, mixes with the acid or
base reagent, and exits  after  adequate reaction  time has  been
provided.  Depending on the pH of the  raw  influent wastewater,
the  tank may be  constructed of a variety  of corrosion resistant
materials  (e.g., stainless  steel or concrete).

An  integral part of  any neutralization system is  the control
system  which usually consists  of one or more  continuous pH
probes  which are connected  to  a microprocessor or other
controller.  Based  on the  signal received from  the pH probes,
either  base or  acid  is added  to the wastewater.   If pH
fluctuations are not too rapid,  a manually operated  control
system  may suffice.   However,  systems  which use  automatic
control have been  found to be  more  reliable than manually
controlled systems.
                                170

-------
4.4  PRIMARY TREATMENT TECHNOLOGIES

The removal of suspended- solids by physical means (e.g.,
settling or flotation) is usually considered to be primary
treatment technology.  Currently, the most widely used primary
treatment operations in the ethanol industry are coarse screen-
ing and sedimentation.  The reduction of solids in primary
treatment reduces the oxygen requirements of downstream bio-
logical units and reduces the solids loading to the secondary
sedimentation tank.

Untreated effluent from ethanol-for-fuel facilities had a median
total suspended solids (TSS) concentration of 380 miligrams per
liter (mg/1) with a maximum concentration of 2,680 mg/1.  Typi-
cal raw domestic sewage has TSS concentrations in the range of
100 to 350 mg/1 (26).  Thus, wastewaters from ethanol-for-fuel
facilities may have concentrations of suspended solids many
times higher than domestic sewage.  If discharged to a POTW,
these solids could result in overloading of the POTWs primary
sedimentation tanks depending on the ratio of ethanol-for-fuel
wastewater flow to domestic sewage flow.  Such high suspended
solids concentrations can bring about problems in secondary
treatment systems.  If the solids are biodegradable, the
secondary treatment system (e.g., activated sludge system,
aerated lagoon) might be overloaded.

4.4.1  COARSE SCREENING

As a method of primary treatment, coarse screening may be used
to prepare,,,wastewater high in suspended solids for either dis-
charge to a POTW or discharge to further on-site treatment such
as an activated sludge system or an aerated lagoon.  The sus-
pended solids present in wastewaters from ethanol-for-fuel
facilities are, for the most part, readily biodegradable.
Removal of suspended solids in a preliminary treatment step may
offer a significant cost savings for plants with complete
on-site wastewater treatment systems.  This cost savings is
possible because removal of biodegradable solids in primary
treatment can result in a reduction in the aeration basin volume
and air supply capacity of the secondary treatment system.
Coarse screens are used in the beverage  alcohol industry and
are used in ethanol-for-fuel plant A03.      -

Coarse woven-wire media screens'are used after bar screens to
remove material prior to introducing wastewater to biological
filters or gravity sand filters.  Screens of this type were
developed in the mid-1960's for use in dewatering pulp slurries
in the pulp and paper industry (27).  They have also been
applied for the treatment of raw domestic sewage  where TSS
removals in the range of five to twenty-five percent have been
achieved (27).
                               171

-------
A rotating wedge wire screen has also been developed that has
the advantage of being self-cleaning and has been found useful
where grease binding problems were encountered with stationary
wedge wire screens.  Rotating screens are also reported to
require less maintenance, they have a lower head loss, and they
require less space than stationary screens.  They also produce a
sludge with a higher solids concentration.  However, rotating
screens have a higher capital cost (27).

4.4.2  SEDIMENTATION/COAGULATION

Sedimentation is the removal of solid particles from a suspen-
sion by gravitational settling.  Sedimentation basins are often
referred to as clarifiers.  Plants A07, Ell, and E12 have
primary sedimentation basins for suspended solids reduction.

The settling characteristics of suspended particles are a func-
tion of the nature of the particles, their concentration, and
conditions in the settling device.  There are no data available
concerning removal efficiency for ethanol plant wastewater;
however, the literature suggests that a properly designed and
operated primary sedimentation tank can remove 50 to 70 percent
of the suspended solids and 25 to 40 percent of the BOD from
domestic sewage (26).

In addition to providing for effective removal of suspended
solids from its effluent, a clarifier must have an adequate
sludge removal capacity and provide sufficient reduction in
sludge volume to facilitate sludge handling and processing.  The
clarifier may also be equipped with a skimming device to collect
scum that floats to the surface.

In the event that the particulate impurities in wastewater are
too small for gravitational settling alone to be an effective
removal process, chemical agents can be added to induce an
aggregation of these small particles into readily settleable
agglomerates which can be removed by some other method (e.g.,
sedimentation, air flotation, or filtration).  This process is
referred to as coagulation.

There are many types of chemical agents (coagulants or coagulant
aids) available, including lime, aluminum and iron salts, syn-
thetic organic polymers, and activated silica.  The type and
dosage of coagulants cannot be determined without some experi-
mentation; the performance of a coagulant is most often evalu-
ated using a jar test.  The removal efficiency in coagulation
depends upon the particles in the wastewater to be treated,
other chemical characteristics of the solution, and the
coagulant aid which is used.
                                172

-------
 4.5  SECONDARY TREATMENT TECHNOLOGIES

 The term secondary treatment refers to the removal of dissolved
 organics that cannot be removed in primary screening or settling
 processes.   Dissolved organics consist of many different
 chemical compounds and are usually measured in terms of the
 generalized parameter biochemical oxygen demand (BOD).  In
 addition to BOD removal, some total suspended solids (TSS) is
 also removed.

 Based on ethanol-for-fuel industry questionnaire responses and
 data gathered by ESE (14)  on the beverage alcohol industry, the
 following distribution of secondary wastewater treatment methods
 were found  to be applied at existing plants:
           of                 %  Plants  Using Technology to Treat
 Secondary Treatment          at Least  Part of their Wastewater

 Aerated Lagoon                             65

 Stabilization  Ponds                        30

 Activated Sludge                -            20

 Trickling Filter                            15

 Rotating  Biological                        10
 Contactors

 NOTE:   Some  ethanol plants employ more than  one of  the  above
        treatment technologies;  thus, the  total does not sum to
        100 percent  (sample population of  24  plants).

 Four ethanol-for-fuel plants have wastewater treatment  systems.
 Plants  A06 and A07  use aerated  lagoons for treatment, plant A03
 uses an activated sludge system and discharges directly to a
 river,  while plant  A01 pretreats with an  activated  sludge system
 then discharges to  a POTW.  In  addition,  trickling  filters and
 rotating  biological contactors  are also applicable  to the
 ethanol-for-fuel industry.  ESE determined in its study of the
 beverage  alcohol industry that  ethanol plant wastewaters are
 typically low in the nutrients  nitrogen and  phosphorus,  which
 are essential for proper growth of the activated sludge
 microorganisms (14).  The data  in Section  3  indicate that
 nutrient  addition is also necessary for the  proper  operation
 ofsecondary  treatment technologies when treating wastewaters
 from ethanol-for-fuel facilities.

 4.5.1  NUTRIENT ADDITION

 In order  to maintain optimum efficiency in biological systems,
minimum quantities of nitrogen and phosphorus are required for

                                173

-------
cell synthesis.  Without a proper nutritional balance, soluble
BODs reduction and liquid-solid separations are impaired.

A summary of typical influent wastewater characteristics for
grain distilleries based on the data presented in Section 3 is
shown in Table 4-2.  As this table indicates, the wastewaters
are deficient in both nitrogen and phosphorus.  To maintain
proper cell growth, nitrogen and phosphorus must be added to the
wastewater.  Nitrogen is usually provided by the addition of
ammonia; phosphorus is provided by the addition of phosphoric
acid.  Both of these chemicals can be stored on-site  in  steel
storage tanks and pumped into the aeration basin at an
appropriate rate.

4.5.2  AERATED LAGOONS

Aerated lagoons are basins  in which aeration is accomplished by
either mechanical aerators  (usually by fixed or floating surface
aerators) or by diffused air piping systems.  The BOD removal
rate is waste specific and  temperature sensitive and  must be
determined by laboratory or pilot unit testing.  Therefore, for
a specific waste and temperature, the BOD removal is  only a
function of detention time  (assuming a completely mixed  aerobic
system).  A single cell aerated lagoon can obtain good removal
of  soluble BOD, but the effluent will contain suspended  solids
in  the same concentrations  as the mixed  liquor.  A greatly
improved effluent  can usually be achieved by following the
aerated lagoon with a second unmixed polishing lagoon where
suspended  solids  are allowed to settle.

There  are  two  common designs  in use:  the completely  mixed  basin
in  which all solids are kept in suspension  (aerobic lagoons) and
the partially mixed aerated lagoon  in which  the  heavier  solids
settle  to  the bottom of the basin .(facultative lagoon).   In the
former design,  stabilization of organics is  entirely  aerobic.
In  the  latter,  the settled  solids undergo anaerobic biological
decomposition  while suspended  and dissolved  organics  undergo
aerobic biological decomposition.

Aerobic  lagoons  have  a  shorter  retention time  than  facultative
lagoons to achieve the  equivalent  soluble  BOD  removal.   However,
a greater  mixing  requirement  and  therefore more  power input is
necessary  for  the aerated lagoon.   Several  aerators are  needed
to ensure  complete mixing  in  the  aerobic lagoon.   These  aerators
provide oxygen and keep the solids  in suspension.   Diffused
aeration  (used at plant A07)  generates  coarse  bubbles and is
recommended where severe winter conditions can render surface
aerators  ineffective.   The effluent from an aerobic lagoon is
 high in BODs caused by unsettled microbial solids.    In order
 to remove  these suspended solids,  some  designers of aerobic
 lagoons include baffled sections which provide for solids
 settling before discharge.
                                174

-------
                             Table 4-2


           TYPICAL  INFLUENT WASTEWATER CHARACTERISTICS
                      AT  GRAIN  DISTILLERIES
„  ^                            Untreated Wastewater
Wastewater Parameter             Grain Distilleries
BOD5


Total Nitrogen (mg/1)                     21


Total Phosphorus (mg/1)                    2


BOD:N:P*                              100:1.4:0.13
*Recommended value of the BOD:N:P ratio is 100:5:1 (28)
                             175

-------
In facultative lagoons, aeration is only required to disperse
oxygen.  The solids are allowed to settle to the bottom of the
lagoon where anaerobic biological degradation of the organic
matter takes place.  Surface aerators are commonly used; in
climates with severe winters diffused aeration may be required.

Figure 4-2 shows the wastewater treatment system in use at Plant
E13 which contains an aerated lagoon.  Also, part of the system
is a stabilization pond which is used to reduce solids and a
chlorinator for disinfection (sanitary wastes are mixed with
ethanol plant wastes).  This plant has a BODs reduction of
94.5 percent and a TSS reduction of 82.5 percent (14).

4.5.3  STABILIZATION PONDS

A stabilization pond is a relatively shallow body of water con-
tained in an earthen basin which utilizes no induced aeration.
These ponds are designed to treat wastewater in the following
manner:  (1) settling of solids;  (2) equalization and control of
wastewater flow; and (3) stabilization of organic matter by aer-
obic and facultative microorganisms, and also by algae.

Stabilization ponds are usually classified  by the biological
activity occurring as aerobic, anaerobic, or aerobic-anaerobic.
Aerobic-anaerobic  stabilization ponds are the second most widely
used biological treatment option by ethanol facilities and are
only found as the  final stage  in biological treatment following
other methods of secondary treatment.  Large ponds allow plants
to store wastewaters during periods of high flow  in the re-
ceiving body of water or for irrigation purposes in the summer.
Stabilization ponds are common  in  rural areas where land  is
available and relatively inexpensive.

Stabilization ponds are usually one to two  meters deep and have
hydraulic  retention times of one  to six months.   In^these rela-
tively deep ponds, the wastewater  near the  bottom may be void of
dissolved  oxygen.  Therefore,  settled  solids may  be decomposed
by aerobic, anaerobic, or facultative organisms, depending upon
lagoon conditions.   It  is essential  to maintain aerobic con-
ditions  in the  top layer of the pond  since  aerobic micro-
organisms  effect  the most complete removal  of organic matter.

Disadvantages of  stabilization ponds  include  their  reduced
effectiveness during winter months which may  require  supple-
mental aeration,  increased  design capacity, and possible
provisions  for  no  discharge during long  periods of  time  (winter
months).   Also, stabilization  ponds require a relatively  large
amount of  land.  Algal growth  may lead  to  high  suspended  solids
 in the effluent.   Odor may  also become  a problem if  the  pond
becomes  anaerobic  (e.g.,  if covered with  ice  during  winter).
                                176

-------
            Gi .
            0)


            t-4
            U-l

            
%
J3r
4-1
Oi
&
           §
            177

-------
No data is available concerning the effectiveness of stabiliza-
tion ponds alone on the effluent from ethanol plants.  In other
industries, stabilization ponds can achieve 8005 removals up
to 95 percent; however, the pond effluent contains a high con-
centration of bacteria and algae that may exert a higher 8005
than the original waste (26).  There are several methods avail-
able for removing algal cells from lagoon effluents, including
coarse-medium filtration (developed primarily for this purpose)
and algal harvesters.

4.5.4  ACTIVATED SLUDGE

The activated sludge system is one of the most frequently ap-
plied methods of biological wastewater treatment.  The process
has shown itself to be capable of high BOD removal efficiency
(85 to 99 percent) and can be adapted to almost any type of
biological waste treatment problem.  This flexibility has led to
numerous modifications of the "conventional" activated sludge
process.  The most common type of activated sludge process in
use today in the beverage alcohol and ethanol-for-fuel industry
is extended aeration.

Extended aeration differs from a conventional activated sludge
process in that it is operated with relatively long hydraulic
residence times and a high sludge age.  Oxygen requirements may
be twice that of a conventional activated sludge unit.  The
extended aeration process is used iri the ethanol-for-fuel and
beverage alcohol industries due to its ability to handle shock
loadings.  Extended aeration activated sludge is used at plants
A01r A03, E06, and E21.

Figure 4-3 illustrates the extended aeration activated sludge
system used at Plant A03.  This process consists of an aeration
tank, a secondary clarifier, pumps, and a sludge recycle line.
Also in this system, the wasted sludge is centrifuged from the
clarifier; the cake is sent to by-product processing at the
ethanol plant and the supernatant is recycled to preliminary
wastewater treatment.  Mixing is accomplished by mechanical
aerators as the sludge flows through the length of the basin.
Adsorption, flocculation, and oxidation of the organic matter
take place during aeration.  The solids are settled in the
secondary clarifier and the resulting sludge, a mixture of these
solids and wastewater, is withdrawn from the bottom of the
clarifier.  A portion of the settled sludge is recycled to the
head of the aeration basin and the excess is sent to a centri-
fuge for concentration.  Effluent from the secondary clarifier
is generally low in 8005 and TSS.  As Table 4-1 indicates,
this facility obtains an average reduction in 8005 and TSS of
98.7 and 95.0 percent, respectively.

Few operating problems are encountered in the activated sludge
processes when the characteristics of the wastewater are ,consis-

                               178

-------
tM
 E

 oo
 II
 IB
 4)
U

I
                                             8S
                                             H
CO
                                                                               H
                              179

-------
tent..  However, the performance of the process can be adversely
affected by significant changes in temperature, pH, and, depend-
ing on the type of activated sludge process, the organic concen-
tration and volumetric flow rate.  The microorganism concentra-
tion in the tank must also be carefully controlled by adjusting
the recycle stream and the amount of sludge wasted.  The concen-
tration of nutrients such as nitrogen and phosphorus must also
be carefully controlled.

4.5.5  TRICKLING FILTER

The trickling filter is a type of attached growth, biological
process for wastewater treatment.  It is used  by three  beverage
alcohol plants and is applicable to the treatment of wastewater
from ethanol-for-fuel facilities.  Trickling filters are often
used in series, with the effluent of one filter becoming the
influent of the following filter.  A portion of the effluent
from the last filter is often recycled to the  initial filter.
There  are  two types of trickling filters:   standard and high
rate.  These trickling filters differ in the distribution and
flow rate  per unit surface area  of the wastewater over  the
filter media.

The trickling filter media has relatively  small openings and
must be preceded  by primary  treatment  to  remove gross  solids  and
debris to  avoid clogging.  A settling tank  equipped with scum-
and grease-collecting devices are  adequate  for this  function.
The trickling  filter  is comprised  of  a wastewater  distribution
system, a  vessel  containing  the  filter media,  an  underdrainage
collector, and  a  partial  recirculation system. The  suspended
solids not removed  by the filter and  those generated  by the
sloughing  of  the  microbial  layer are  removed  in a  final
sedimentation tank.

The  operation and maintenance problems  associated with the
trickling  filter  are  few  and can be minimized by  proper design
considerations.   The  filter media may be stone or some type of
 synthetic  material  such as polyethylene  saddles which provide a
 high surface area per unit volume, a  high void space per unit
volume,  durability,  and a resistance  to  clogging.

 Figure 4-4 illustrates the wastewater treatment system used at
 plant E17 which incorporates two trickling filters in  series
 that  follow an aerated lagoon.  This system also uses  two
 polishing lagoons (the first aerated and the  second not aerated)
 to achieve an effluent with a BOD5 reduction  of 97.2 percent
 and a TSS reduction of 76.1 percent (14).

 4.5.6  ROTATING BIOLOGICAL CONTACTORS (RBC)

 An RBC provides a secondary wastewater treatment technique
 effected  by attached biological growth.  RBCs are used at two

                                 180

-------
i
=
                                                      9
I



I

e
I
III
   s .

   17
                           181

-------
beverage alcohol facilities and are applicable to the treatment
of wastewaters from ethanol-for-fuel facilities.

The RBC treatment process is often preceded and followed by
clarifiers for solids removal.  The closely spaced, molded
polystyrene disks that are three to four meters in diameter are
mounted on a common shaft.  The set of disks -is partially (40
percent) submerged in a cylindrically bottomed tank.  A series
of these tanks with the shafts parallel are positioned between
the two clarifiers; no  recirculation of sludge is required.

After a biological film on the surface of each disk has grown,
the rotating action of the disks (one to two rpm) shears off  -
excess microbial growth, keeps solids in the tank in suspension,
and provides oxygen thereby reducing aeration requirements.-  The
attached suspended microorganisms adsorb and assimilate the
organic wastes.  The thin layer of water that adheres to the
surface of the disk as it rotates and the large surface area
covered by the biofilm provide a high microorganism to food
ratio, and a high degree of oxidation can be carried out
quickly; contact times are generally less than one hour.  The
high degree of oxidation eliminates the necessity of recir-
culating part of the effluent and therefore pumping requirements
are minimal.  The sloughed biomass has good settling charac-
teristics and can be easily separated from the waste stream in
the final settling tank.

The operating and maintenance problems associated with the RBC
process are fewer than those of trickling filters, but startup
problems can occur in establishing the biofilm.  However, once
the system is established, power outages or downtimes of a day
or two require only a few hours to bring the system back to
equilibrium.  The RBC treatment system is usually enclosed to
avoid freeze up.

Figure 4-5 shows the wastewater treatment system for Plant EOS
which features three RBCs in series.  The first RBC receives the
effluent from an aerated lagoon and the third RBC discharges to
a second aerated lagoon which is followed by three ponds used to
settle solids.  Finally, the last pond discharges to an air flo-
tation unit used to remove algae and other solids which are
difficult to settle.  This system achieves BODs and TSS
reductions of 97 and 73 percent, respectively.  BODs and TSS
removals of 50 and 10 percent, respectively, are achieved by the
RBC units alone (14).

4.6  TERTIARY TREATMENT

In an ethanol-for-fuel wastewater treatment facility, tertiary
treatment would receive the effluent from the secondary treat-
ment system.  Based on treated effluent data this secondary
effluent typically contains 40 mg/1 TSS as biological floe, with

                              182

-------
   s
S  §
0)  G
                              0)
                              VI
                              o
                              u


                              S
          S  u
          g  „
o
s
  3
           eg
           u

           S
           a
                                2
                                                                                       co

                                                                                       ><
                                                                                       CO

in
l

-------
peaks  of  perhaps  120 mg/1.   The  effectiveness  of  tertiary
treatment is affected   by the  origin of  the  wastewater.  Three
tertiary  treatment  systems  which are considered applicable  to
the ethanol-for-fuel industry  are granular-media  filtration, air
flotation, and  land application.

4.6.1  GRANULAR-MEDIA  FILTRATION

This process consists  of passing wastewater  through  a packed bed
of granular material of a depth  on the order of one  meter or
more,  wi.th resulting deposition  of solids  in the  granular mate-
rial.  Deposition occurs by a  combination  of physical mechanisms
(i.e., mechanical straining, chance-contact  straining, sedimen-
tation, impaction,  interception,  diffusion, and adhesion) which
are discussed by Metcalf and Eddy (26) and Weber  (29).  The
wastewater is diverted  from a  filter unit, and the unit is taken
off line  when (1) effluent  quality reaches an  unacceptable level
due to the inability for the given bed depth to hold the solids
(breakthrough), (2) a  limiting headloss  occurs across the bed
due to  accumulated solids  (terminal headloss), or (3) the fil-
ters are  backwashed oh  a time  cycle basis.  After the units are
taken off line, the bed is  backwashed by passing  water upward
through the bed to  expand it,  allowing the shearing  action of
the water to remove the deposited solids.  Backwash  is often
supplemented by internal or surface water  jets or air scouring.
The backwash wastewater can be recycled to primary sedimentation
or to  the biological treatment unit.

Options for flow direction  include downflow  (conventional),
upflow, and biflow.  Historically, downflow systems have
predominated (27) since they have the advantage of supplied
hydrodynamic head.  A discussion of the less frequently used
upflow and biflow systems can  be  found in  (27).

Particle  size and size distribution of the media  have major
effects on filter performance.   Finer media particles possess
greater removal abilities than do coarser  particles, but they
also result in greater headloss per amount of solids removed
(27) due  to premature bed clogging.  The problem  of particle
size gradation can be alleviated with the use of  two or more
media.  By layering a coarser, less dense medium  over a finer,
denser one (e.g., coal over sand), a downflow configuration can
be combined with a coarse-to-fine gradation in the direction of
flow.  A further refinement involves multi-media  (three media:
typically coal over sand over garnet).   The gradation can also
be eliminated with the use of uniformly sized particles.

As a tertiary treatment technology, granular-media filtration
can be expected to reduce levels of 30 mg/1 TSS in the influent
stream to concentrations of 10 mg/1 (27).  Supplemental removal
of particulate BOD remaining after biological or  chemical treat-
ment is achieved by filtration.

                               184

-------
  Pilot-plant  studies  for filtration are required to ensure proper
     G     iT  S~CS  the characteristics of  the influent LI- P
            1?8  ^      ^ Perf otraance.   Although granular-media
            has been  extensively  used in treating the  effluent of
  ni«n       ^reatment Processes at domestic  wastewater treatment
  eth±i' ^   r n0t bSen USSd f°r tertiary treatment purposes in
  ethanol plant  wastewater treatment systems.
 4.6.2  AIR FLOTATION
 ?hJ Ji™at*°n i? a techni<3ue which removes suspended  solids  in
 the form of a floating sludge,  it can be either purely physical
 °  Phvsical/chemical With the ^ition of chemica? coagufants
               Uni1?s.9enerate air bubbles, and the buoylncy of
               8 riS1?9 throu9h the wastewater lifts suspended

                eSUrfaCe-  ^ fl°at
ei^no?h airf10tati°n  is  not  widely  used  in  the  treatment  of
ethanol plant wastewater,  it is being used by plant  E15  to
remove algae and suspended  solids  from  its aerated lagoon
effluent.  This facility employes  a dispersed air flotation
system which uses diff users to form air bubbles.

^a?lA£3 reports thf?  the effluent from its  activated sludge
unit  Wha?hP°°r Sf^in? <=ha^cteristics.  An air flotation
unit, which is relatively compact  in size and produces a fairlv
°°at?d Slud9e' m^ *e a viable alternative to a secondar?
              removal of suspended solids from secondary treat-
           s such
   n   ,                                   s  rom seconary treat
ment  systems  such  as  activated sludge.   However,  air flotation
                              and may produoe
 4.6.3   LAND APPLICATION  OP WASTEWATER
   J

 In the  land application  of wastewater,  filtration  of  solids  and
 biological decomposition are  provided by vegetation,  the soil
  ndl                    '                        eoo
land application  of  wastewater  are  slow  rate,  rapid  infiltra-
tion, and overland flow.   Less  widely used methods
wetlands and subsurface application (30).
Slow rate treatment  is also known as spray  irrigation- however
in this case the irrigational effect is secondary to the ?relt-
ment of wastewater.  In slow rate treatment, waJtewater is
SrrnooS"1 3 fe8frYolr and ^Plied to the  soil via a sprinkler
H^?H \ S I 9 techni(3ue-  The disposition of the water is
divided between percolation and vegetative  uptake and, there-
fore, both the soil and vegetation are critical in managing the
wastewater and its constituents.  Organics  are reduced by
biological oxidation within the top few inches of the soil
Suspended solids can be removed to a level of one mg/1 or less
                                185

-------
by filtration.  Volatile solids are biologically oxidized, while
mineral solids become a part of the soil matrix.  The slow rate
process is applicable to agricultural land, grasslands, forest
land, and public land such as parks and golf courses.

Rapid infiltration (also known as infiltration-percolation)
involves application of the wastewater to a highly permeable
soil via sprinklers or flooding basins at a greater rate and
upon a smaller area than in slow rate treatment.  In rapid
infiltration, the soil serves essentially as a  filter medium.
The water percolates to underdrains, wells, or  groundwater;
little evaporation or vegetative uptake occurs.  Removal o£
suspended solids and BOD by filtration and straining is nearly
complete (30).

Overland flow involves  the  application of  wastewater to the
upper  areas  of  a  sloped terrain which possesses a  low
permeability soil or a  subsurface  barrier  to  percolation.   The
wastewater  flows  down  the  vegetated surface  as  a film  and  is
collected at the  base  for  either reuse or  discharge.   Organics
and suspended solids  are removed by biological  oxidation,
sedimentation,  and  grass filtration (30).

Of the three types  of  land application  processes,  the  slow rate
method is  most compatible with crop cultivation.  Furthermore,
whereas rapid infiltration requires,a highly permeable soil and
overland flow requires a soil of low permeability,  slow' rate
operates within a wider and more moderate range.  Finally, the
 slow rate process produces effluent of the highest quality.

 One ethanol-for-fuel facility in the United States (plant A01)
 currently practices land application of wastewater; however,
 this facility is constructing an activated sludge system which
 will then discharge to a POTW.  There is also one beverage
 alcohol facility (plant E21) which practices land application.
 Both of these facilities employ the slow rate process; neither
 overland flow nor rapid infiltration is employed by the ethanol
 industry.

 4.7  DISINFECTION

 Disinfection is the elimination of selected disease-causing
 organisms.   This selective elimination differs  from
 sterilization, a process which kills all organisms.  Dis-
 infection is necessary  if sanitary wastes are  sent to the
 wastewater  treatment system.   Currently, chlorination is the
 only  practiced means of disinfection.

 Chlorination is used for  final  wastewater disinfection primarily
 bv those plants that combine  sanitary wastes with raw wastewater
 effluents  (plants  A04,  EOS,  EOS,  Ell, and E12).  Disinfection
 effectiveness generally has  been measured by the concentration

                                186

-------
 of the coliform bacteria indicator group that remains after
 disinfection has taken place.  Alternatively, chlorination
 utilizes a more indirect measure of residual chlorine, which "
 provides presumptive evidence that adequate disinfection was
 achieved.

 Chlorine is highly corrosive when wet; thus, the gas is stored
 dry,  under pressure.  It is mixed with water to form an aqueous
 solution prior to injection to the wastewater stream.  The aque-
 ous chlorine solution is mixed with the wastewater in a dif-
 fusion chamber; the wastewater plus chlorine then enters a
 chlorine contact tank,  which provides the appropriate detention
 time  before discharge to the receiving water.  The chlorine
 dosage required for disinfection will vary with the quality of
 the effluent to be treated.  To ensure proper disinfection,
 ™*i  ?  K?  ?rinS mUSt be added to force the formation of free
 residual chlorine.  The presence of free residual chlorine can
 easily be monitored to  check if adequate chlorine has been
 added.

 One disadvantage of chlorination for disinfection is that it
 reacts with organic compounds.   Groups are  formed which  often
 ™™* Vf f5?M?hlorine. residuals;  they possess little  or no
 germicidal  ability and  give an  overestimate of  the free  residual
 present.   Also,  many undesirable chlorinated organics formed
 during chlorination are suspected to  be  carcinogenic.

 The germicidal  effect of chlorine is  believed to be due  to the
 reaction of chlorine compounds  with  the  cell membrane of the
 bacterial  cell,  thereby stopping  the  metabolic process.   Viruses
 are also  affected,  but  not  in the same correlative,  quantifiable
 way as with bacteria.   Among the  conditions which  affect the
 germicidal  effectiveness are contact  time,  chlorine concentra-
 tion,  NH3-N concentration,  intensity  of  light, temperature,
 pH, number  and  types of  organisms, and the  nature  of  the
 suspending  liquid.   In  a  well-designed contact chamber,  the
 reduction  of coliform content should  exceed 99 percent,  with
 minimal residual chlorine (less than one mg/1).

 4.8  SLUDGE  HANDLING

 The biological treatment of wastewaters  results  in  the
 generation  of excess  biological solids which must  somehow be
 disposed.  A portion of the waste material present  in the raw
 wastewater  has been concentrated  in the  form of  biological
 solids; thus, by cleaning the water, a potential solid waste
 problem is created.   This problem has  been a recognized area of
concern since the advent of biological wastewater treatment, and
 numerous technologies are available to dewater, stabilize, and
recover waste biological sludge.
                               187

-------
One typical scenario that  is evaluated  in this section  is shown
in Figure 4-6.  Waste sludge from the secondary settler is sent
to a gravity thickener, where  further settling increases the
sludge concentration.  Concentrated sludge is sent to an aerobic
digester, where a  portion  of the cell matter  is oxidized to
carbon dioxide.  This brings about a reduction in the net mass
of waste sludge.   The effluent from the aerobic digester is sent
to a solids centrifuge, where  additional water is removed,
resulting  in a semi-solid  sludge with a solids concentration  of
up to 20 percent.   This sludge can then be trucked to a sanitary
landfill for final-disposal.   Ultimate  disposal methods for
dewatered and stabilized biosludge as well as for other solid
wastes  from ethanol facilities are discussed  in Section 5 of
this document.

.4.8.1   GRAVITY SLUDGE THICKENING

A gravity  sludge  thickener is  essentially  the same piece of
equipment  as  a  secondary  settler  except that  the  feed,  effluent,
and  underflow solids concentrations  typically found  in  a  sludge
thickener  are much higher  than those found in a  secondary  set-
tler.   There may  also be  slight differences  in  the  torque
rating, sludge  rake designs,  and  effluent  weirs.

 Influent sludge  enters a gravity  sludge thickener at concentra-
tions  of 5,000  to 25,000 mg/1.  The  underflow solids concen-
 tration in gravity thickeners treating  waste  activated sludge
ranges from 15,000 to 40,000 mg/1.   The overflow from the
gravity thickener has a suspended solids content of 100 to 350
mg/1 and a BODs  of 60 to 40° m9/:L (26)<  Due  to lts  high
 solids and BOD5 content,  the  thickener overflow is usually
 sent back to the aeration basin for further treatment.

 4.8.2  SLUDGE DIGESTION

 Aerobic digestion can be used to stabilize biological sludge,
 primary sludge, or a combination.  Plant A10 uses separate
 aerobic digestors  for the stabilization of mixtures of excess
 activated and primary sludges.  The digestion process  involves
 oxidation of sludge in either a surface-aerated or a diffused
 air basin.  The major components of an aerobic digester system
 include a tank, an aeration system, a  thickener, and sludge
 pumps.

 Compared to other methods of  sludge stabilization (particularly
 anaerobic digestion) aerobic  digestion produces a biologically
 stable, odorless  end product  and a supernatant liquor  with a
 lower  BOD content than that from anaerobic digestion;  this is
  important  in recycling supernatant to  avoid  overloading the
 treatment system  (Benefield and Randall,  1980).  Also, the
 capital cost of  aerobic digestion is generally lower than that
  for anaerobic digestion and fewer operational problems will

                                 188

-------













c
•H
co
CO
S3
o*^ —
•r4
4J
CO

<

o

Return
*
^
i
CO
0)
^4
4J
03

•o
i 1
f-l
i-4
r^ i-(
CO 






4
00
C
1-1
(4
0)
CO
3

Q
C
^







.
O
**H
4J
CO
N
' i-l
f— «
•H
J3
«
i t
3 i k OT
5
•^^
J





X 0)
4J 
-------
occur than with anaerobic digestion; therefore, maintenance and
labor costs may be reduced.  Finally, aerobically digested
sludges have a higher fertilizer value than do those from
anaerobic digestion.  Disadvantages of aerobic digestion include
high power requirements for oxygen supply, and the fact that
aerobically digested sludge is often difficult to dewater
resulting in a supernatant from subsequent thickening that is
high in suspended solids.

4.8.3  SLUDGE DEWATERING

Two methods of sludge dewatering which are used in the beverage
alcohol  industry and are applicable  to the treatment of waste-
waters from the ethanol-for-fuel industry are  solids centrifuge
and sludge drying lagoons.

Solids Centrifuge

The influent to the solids .centrifuge enters  at a  typical  con-
centration of  30,000 mg/1.  Solids are forced  to the inside wall
of the rotating bowl and collected by the rotating conveyor.
Liquid centrate passes out the other end of the centrifuge.   The
centrate will  have  a TSS concentration in the  range of  2,000  to
15,000 mg/1 and a BODs concentration between  1,000 and  10,000
mg/1.  Thus, this stream  is generally sent back to the  aeration
basin for further treatment.   Since  the  flow  rate  is so small,
no modification of  the aeration  basin design  is required.
Solids leave the centrifuge at 10  to 35  percent solids.   Sludge
at this  concentration  is  semi-solid  and  can easily be  trucked to
a landfill  for final disposal.

Sludge Drying  Lagoons

Sludge drying  lagoons  provide a nonmechanical means of de-
watering the  waste  sludge produced during biological  wastewater
treatment.   Before  the sludge is pumped  into  the  lagoon,  it must
be  digested for  stabilization and reduction  of odor  emissions.
Although the  sludge lagoon itself may provide additional  stabi-
 lization, the primary function is dewatering.  Lagooning  is not
capital  intensive and does not require  significant maintenance;
 however, it is a land-intensive operation,  and odor  may be a
 problem.

 In a sludge drying lagoon, the digested sludge is pumped into
 the bottom of the lagoon and left to dry.  Evaporation is the
 primary mechanism by which dewatering occurs, with supernatant
 removal  and permeation of the fill  lining contributing minor
 amounts  to dewatering.  Any supernatant which exceeds the
 overflow level is pumped back to the treatment plant.

 Depending on the design of the sludge drying  lagoon, a high  (>30
 percent  solids)  or low concentration of suspended solids in  the

                                190

-------
dewatered sludge can be achieved prior to removal.  A high
solids concentration sludge is mechanically removed from the
lagoon by a front-end loader, and can be used as a soil con-
ditioner or fertilizer.  A liquid product with a low concentra-
tion of solids can be pumped from the lagoon into tank trucks
and land applied.

Residence times for dewatering depend on the sludge depth in the
lagoon.  After sludge removal, it is recommended that a six-
month rest separate emptying and refilling.  Therefore, at least
two sludge lagoons should be present at any location.

4.8.4  RECOVERY

Grain alcohol producers who recover stillage can also recover
the wastewater treatment sludge by incorporating this sludge
into by-product grains.  In the by-product grain recovery
system, thestillage is first screened; the screened solids are
concentrated  in centrifuges, evaporators, and dryers.  The thin
liquids from screening are recycled to the ethanol process or
sent to wastewater treatment.  The sludge produced in wastewater
treatment can be dewatered and mixed with the stillage in the
dryers, then sold as a by-product cattle feed if sanitary waste
from the plant is not sent to the wastewater treatment system.
Thus, the recycle of sludge, which has been practiced for many
years by the grain alcohol industry, is the preferred option for
ethanol-for-fuel producers using grain.

Previous studies of the beverage alcohol industry show that fer-
mentation of sugar feedstocks (cane molasses, citrus molasaes,
and sugar cane) produces: a stillage low in protein content which
is not as nutritional as grain stillage.  Therefore, the common
practice with this low-protein stillage is treatment and/or
disposal.
                                191

-------

-------
                            SECTION 5

       SOLID WASTE TREATMENT AND DISPOSAL TECHNOLOGIES
For many ethanol-for-fuel producers that process grainr it will
be profitable to recycle and reuse or recover for sale as
by-products all wastes associated with ethanol production.
However, if the wastes are not recovered, the distiller must
comply with Subtitle D (RCRA 4000 Series) regulations which
require nonhazardous solid wastes to be disposed of by sanitary
landfill. Application of this waste to land used for growing
food chain crops is acceptable because excessive levels of heavy
metals (lead, cadmium) are not found in the waste.  Although no
analysis for PCB's was performed, those compounds are not
expected to be present based on best engineering judgment.

Table 5-1 presents the treatment and disposal technologies for
solid waste currently used in the fermentation ethanol industry.
These technologies are used in many industries and are adequate
to effectively treat ethanol process wastes.

5.1  RECYCLE/REUSE

Ethanol-for-fuel producers who recover stillage can also recover
the wastewater treatment biosludge by incorporating this sludge
into by-product grains.  However, the sludge may be reclaimed
only if sanitary wastes have not been incorporated into the
wastewater treatment system.

In the by-product grain recovery system, the stillage is first
screened? the screened solids are then concentrated in centri-
fuges, evaporators, and dryers.  The dewatered, stabilized bio-
sludge can be mixed with the stillage in the dryers, then sold
as a by-product cattle feed.

The recycle of sludge, which has been practiced for many years
by several beverage alcohol producers, is the preferred option
for ethanol-for-fuel producers using grain.  The cost of sludge
recovery is offset by the sale of the recovered sludge as
by-product.  Also, sludge recovery would require little capital
cost since the equipment used is already installed for
by-product processing.

Previous studies of the beverage alcohol industry show that
fermentation of sugar feedstocks (cane molasses, citrus
molasses, and sugar cane) produces a stillage low in protein
                                192

-------

-------
in

CD
      OS

      £

      CO
      u
H Q
   M
J J
< O
CO CQ
O
eu H
co z

22

1
•O 01
JJ
c
2
e
CD
Ol CO
10 CD
C 0
(0 -H
£ JJ
X O
tH (0
10 i-l
co CM
o
Oi
CO
•I-l
Q
c c
5in
X 3
C (0
O OS
•H
JJ JJ
(0 O
U (0
•M U
iH JJ
a c
f% O
*^s o
X
*O *"^
C f-f
(B -rt
.J Mj

1
TJ Oi
C C
10 -H
J iH
X 3
C Q
0 3C
•1-4
JJ JJ
10 U
O (0
•p>4 £4
>H JJ
ac
a o
< o
X
•a -4
C f-4
(O-H
hJ It)
CO
JJ
o
3
•O
2
cu

^
CQ

C — •
•H OI
C
c •«•<
O E

co 
<

•o

1
     I"
                                                        •a
                                                        0)
                                                        (D
                                                        b
                                                        (0
                                                        i?
                                                        10 -H

                                                        X 3
                                                        C (0
                                                        O X

                                                        4J JJ
                                                        (0 O
                                                        U (0
                                                        C   -f4
                                                        CO
                                                        (0
                                                       1%
                                                       $8
                                                       •O
                                                       fH    C
                                                        O    <0 -H
                                                       CO
                   C
                   o
                   •H
                   JJ
                   
?
iH
O
c
£
u
CD
H

JJ
C
JJ
|Q
CD
H
C JJ
< (0
IiJ
It ^^J
0 C
CD
U O
•* C
£ O
00

CD *
< c
0
CT-U
e co
•H CD
Aa Ol
jj a
(0
5 0
Mk 	 1
c
o
•H
JJ
CO
CD
O»
•i-l
Q

O

!o
o

CD


o> 01
e 01 c
•H C 'ft

CD *C CD
JJ O JJ

















Oi
•H
Jj
CD
JJ
<0
                                                             o-

                                                        O)   JJ
                                                        c    co
                                                       •H    CD
                                                        ^i    Ol
                                                        ^j   »»^
                                                       Q   a


                                                        %    °
                                                        O   -H
 •o

 n
     OS
                              a>
                              a
                                                       o
                                                  JJ
                                                  c
                                                  CD
                                                  U


                                                  I
                                                            CD
                                                            <0
                                                            C
                                                            h
                                                            o
      o
      14
      CD
                                                                    C
                                                                    o

                                                                    JJ
                                                                    CO
                                                                    CD
                                                                    Ol
 U
 •H
 £
 O

 CD
 i
       O JJ O
      •fH O CD
      M Q) OS
       a u
                        %'
                             CO
                           C CD
                        •O M O
                        C    O
                        tit  Ij I [

                        M  O 04
                        (0
                       •o
                        c
                        o
                        u
                        CD
                       CO
                                                                             a!
I   a
                 CQ
                 0)
                 JJ
                 CO
                 10
                 o
                 CO
                 JJ
                 c
                 Q)
                 JJ
                 Q)
                 Ol
                 •O

                 iH
                 CQ
                 O
                 •H
                 CD
                                                 •H

                                                 JJ

                                                 CO
 0)
 Q)
OQ


 O
 U
U-l

 0)
Oi
(0
                                                      JJ
                                                      CQ
                                                                        CD
                                                                        JJ
                                                                   JJ
                                                                   CO
CO
CO
0)
o
o
                                           193

-------
content which is not as nutritional as grain s tillage.  There-
for eTthe common practice with this low-protein stillage is
treatment and/or disposal.


5.2  TREATMENT TECHNOLOGIES

qolid wastes which  contain large  amounts of water  (up to 95 per






volume   of  the waste.   The concentrated waste  is  then digested
Teller aerobically or anaerobically)  to  produce  a stabilized
solid waste.

 5.2.1   DEWATERING

 Three  methods of dewatering  which are used in the beverage
 concentration
 the ranae of  2,000 to 15,000 mg/1 and a BOD5 concentration
treatment.
              Solids  leave  the  centrifuge at  10 to 35
  applied.







                                 194

-------
 sludge  lagoon itself  may  provide additional  stabilization,  the
 primary function  is dewatering.   Lagooning is  not  capital  inten-
 sive  and does not require significant  maintenance;  however,  it
 is  a  land intensive operation  and odor is a  continuing  problem.

 In  a  sludge  drying lagoon,  the digested sludge is  pumped into
 the bottom of the lagoon  and left to dry.  Evaporation  is  the
 primary mechanism by  which  dewatering  occurs,  with  supernatant
 removal and  permetation of  the fill  lining contributing minor
 amounts to dewatering.  Any supernatant which  exceeds the
 overflow level is pumped  back  to the treatment plant.

 Depending on the  design of  the sludge  drying lagoon, a  high  or
 low concentration of  suspended solids  in the dewatered  sludge
 can be  achieved prior to  removal.  A high solids concentration
 sludge,  which is  typically  30  percent  or more,  is mechanically
 removed from the  lagoon by  a front end loader,  and  used as a
 soil  conditioner  or fertilizer.   A liquid stream with a solids
 concentration of  3 to 6 percent  is pumped from the  lagoon into
 tank  trucks  and land  applied.

 Residence  times for dewatering depend  on the sludge depth in the
 lagoon.   After sludge removal, it is recommended that a six-
 month rest separate emptying and  refilling.  Therefore, at least
 two sludge lagoons should be present at any  location.

 Gravity  Thickening.   A gravity sludge  thickener is  essentially
 the same  piece  of  equipment as a  secondary settler  except that
 the feed,  effluent, and underflow  solids concentrations typi-
 cally found  in  a  sludge thickener  are  much higher than  those
 found in a secondary  settler.  There may also  be slight dif-
 ferences  in  the sludge rakes and  effluent weirs.

 Typically, influent sludge enters  the  gravity sludge thickener
 at  concentrations  of  5,000 to  25,000 gTSS/m3.  The underflow
 solids concentration  in gravity thickeners treating waste acti-
 vated sludge  ranges from 15,000 to 40,000 gTSS/m3.   The over-
 flow from the gravity thickener has  a  suspended solids content
 of  100 to 350 gTSS/m-s and a BOD5 of  60  to 400 gBODs/m3
 (26).   Due to  its high solids and  BODs  content, the thickener
 overflow  is  usually sent back  to the aeration basin for further
 treatment.

 5.2.2   STABILIZATION

 Solid  wastes are stabilized in order to:  reduce pathogens,
 eliminate offensive odors, and inhibit, reduce, or  eliminate the
potential for decomposition of  organic  matter  (26).  The two
most widely used means of stabilization for the ethanol industry
are aerobic and anaerobic digestion.   These methods biologically
reduce the volatile content of the solid waste, thereby reducing
the survival of pathogens, release of odors,  and decay of
organic matter.
                                195

-------
Aerobic Digestion.  Aerobic digestion can be used to stabilize
logical sludge, primary sludge, or other solid wastes.  Plant
A10 uses separate aerobic digesters for the stabilization of
mixtures of excess activated and primary sludges.  The digestion
nrocess involves oxidation of the solid waste in either a
lurllcf-aerated or a diffused air basin.  The ma3or components
of an aerobic digester system include a tank, an aeration
system, a thickener, and sludge pumps.

Compared to other methods of sludge stabilization  (particularly
anaerobic digestion) aerobic digestion produce.s a  biologically
stable, odorless end product and a supernatant liquor with a
lower BOD content than that from anaerobic digestion; this is
important in recycling supernatant to avoid overloading the
treatment system  (28).  Also, the capital cost of  aerobic
digestion is, generally lower than that for anaerobic digestion
and  fewer operational problems will occur than with anaerobic
digestion; therefore, maintenance and labor  costs may be
reduced.  Finally,  aerobically digested sludges have a higher
fertilizer value  than do those from anaerobic digestion.
DiladvanSges  of  aerobic digestion  include high power ^quire-
ments  for oxygen  supply, and the  fact that aerobically digested
sludge  is often difficult  to dewater  resulting  *"/ supernatant
from subsequent thickening that  is high in suspended  solids.

Anaerobic Digestion.  Anaerobic  digestion of secondary waste-
water  treatment sludges  is a very sensitive  process.  *requent
upsets have  led to  the use of  aerobic digestion  (28).  Unless
all solid wastes  from the  ethanol production process  are con-
solidated  and  fed to the  anaerobic digester, as  with  the
A^AMM® process,  the value of  the methane  generated is minimal
 in offsetting  the cost  of  digestion.   Two  of the beverage
 alcohol plants surveyed currently use anaerobic digestion.

 5.3  DISPOSAL AND MANAGEMENT PRACTICES

 Solids which cannot be sold or recycled as well as treated,
 stabilized sludge must be disposed of safely.   Two methods for
 ulSimaie disposl! of solid wastes are practiced by the  beverage
 alcohol and ethanol-for-fuel industries-,   contract hauling to a
 landfill and land application.
 Contract Hauling to a Landfill.  Options for solid waste
 al by landfill for wastes which have been stabilized to reduce
 odor and sufficiently dewatered for handling Purposes  (> 20 per-
 cent solids)  (31) include handling and disposal by the ethanol
 Sroducinq facility on-site, contract hauling and placement
 ^n-si?e?9anrcontract hauling to a landfill site not owned by by
 the ethanol  facility.  The common practice to date for beverage
 SSohS JlinS whicS produce a secondary treatment sludge is to
 hire a contractor to remove and dispose of the solid waste.
                                 196

-------
The economics of the disposal of industrial wastes by contract
methods are a function of location, method of disposal, and the
distance from the plant to the disposal site.  Sanitary landfill
of a solid waste represents a relatively inexpensive form of
disposal (32).

Land Application*  Stabilized sludge may be land applied in
either liquid or semi-solid form.  If applied as a liquid, the
sludge contains 90 to 97 percent water.  If applied as a semi-
solid, the sludge contains 60 to 80 percent water.  Currently,
only one ethanol-for-fuel plant in operation uses land
application as a means of sludge disposal.

According to Gulp (33), there are two approaches for land
application of sludge:  (1) apply the sludge to land used for
growing agricultural products or other vegetation, or (2) dedi-
cate an area to sludge disposal with no attempt to grow crops.
The advantages of using farmland for disposal are the use of
nutrients in the sludge such as nitrogen and phosphorus.  Care
must be taken, however, to avoid pollution of the ground water
or heavy metals buildup in the soil and food chain.  Heavy
metals buildup can be controlled by monitoring the loading rate
at which the sludge is applied and periodically testing the soil
for heavy metals buildup.  The sludge loading rate can then be
adjusted, as required to comply with development of the regula-
tions.  Although application of sludge to forest or agricultural
land poses possible health, safety, and odor problems, it might
be the most feasible method of ultimate sludge disposal/
management from an economic as well as environmental point of
view.
                                197

-------

-------
                            SECTION  6

            COST, ENERGY, AND NONWATER QUALITY ASPECTS
                     OP WASTEWATER TREATMENT


In order to as-sess the overall economic impact of pollution
control on the ethanol-for-fuel industry, an engineering an-
alysis was conducted to determine:   (1) the typical wastewater

Shn^t-Pr°b/tI!lS.2f thS industrv'  <2) the applicable treatment
technoloies
    hn-/.               '                   e  rea
 technologies,  (3)  the cost and energy requirements of these
 technologies,  (4)  the effectiveness  of these technologies in
 reducing  pollutant discharges from the industry, and (5)  the
 nonwater  quality  impact from the proposed regulations.

 An  economic  impact analysis was also performed to investigate
 5?? ™^*Y  °f  i^ust^Y to pay the cost of wastewater treatment.
 The results  of  this analysis for the ethanol-for-fuel industry
 are beyond the  scope of this document and are presented in a
 separate  EPA document (34).

 6.1 MODEL PLANT COSTING

 6.1.1  MODEL PLANT CONCEPT

 In  order  to  conduct  an  economic  impact  analysis  of  an industry,
model plants are developed.   A model plant is an engineering
concept useful  in  attempting  to  assess  overall industry costs
from technologies  which must  be  designed  on  a plant-specific
basis.  Rather  than  calculate  the  individual  cost of  installina
wastewater treatment systems  at  each plant in the industry  and
summing these costs,  the Agency  bre.aks  the plants down into
groups and lets each group of  plants  be represented by a model
plant.

To calculate the total  industry  cost  of installing a  particular
technology using the model plant concept,  the cost of installing
the technology at each of the model  plants is  first estimated.
Since the model plants  cover  the same general  range of produc-
tion capacities as the real plants,  any economies-of-scale or
other size-related effects on  the cost of  the  technology are
incorporated  in the cost estimates.  The total cost to the
industry is calculated by multiplying the  cost of a given
technology for a model plant by the number of real plants that
the model plant represents.
                               198

-------

-------
 6.1.2   SIZE  DISTRIBUTION OF  ETHANOL-FOR-FUEL MODEL PLANTS

 The  existing ethanol-for-fuel  industry  and  future  growth trends
 were described  in  Section  2, Industry Profile.   For this study
 which  was  performed  in  1981, it was  assumed that a very substan-
 tial increase in the number  of ethanol  plants was  expected  in
 the  next 10  years, with a  wide range of production capacities.
 The  plants were classified as new or existing plants.  Existing
 plants include  those which are in operation as well as those
 under  construction.  The new plants  include those  for which
 construction is initiated  after this study.   The proposed
 facilities discussed in the  industry profile  were  used to
 characterize the new plants.

 After  a thorough -review of all the available  information on new
 and  existing plants, five  model plant production capacities were
 selected as  indicated in Table 6-1.  These  sizes were selected
 because they covered the full range  of  expected  plant sizes and
 best represent  the distribution of plants.  The  number of plants
 of each size for each plant type is  shown in Table 6-1.  In 1981
 there  were 15 currently operating ethanol-for-fuel facilities
 and  35 under construction; there were 42 proposed  plants in some
 stage  of discussion or  planning.

 6.1.3   MODEL PLANT WASTEWATER CHARACTERISTICS

 Typical characteristics of the raw wastewater produced by an
 ethanol-for-fuel plant  are presented in Table 6-2.  These char-
 acteristics  were used to represent the  untreated effluent in all
 of the  treatment system design work presented here.  Table  6-2
 was  prepared by analyzing  all the available data on ethanol-
 for-fuel untreated effluent including:   (1) long-term data  (six
 months  or  more) available  from four  ethanol plants,  (2) EPA's
 sampling data as discussed in Section 3, and  (3) various sources
 from the literature  (14,25,35,36).

 The  available data for  the facilities examined indicate wide
 variation  in wastewater characteristics;.influent  BODs ranges
 from 500 to  2,400 mg/1  with an industry mean of  1,406 mg/1.  As
 indicated  in Table 6-2, a value of 1,500 mg/1 was  selected  to
 represent  the untreated effluent BODs concentration for the
 model plants.  Values for  influent TSS and the other parameters
 listed  in  Table 6-2 were selected in a similar manner.

 There was  no information available which indicated  that waste-
 water concentration varied as a function of size.  Thus,  the raw
 wastewater composition  shown in Table 6-2 has been assumed  to
 describe the wastewater at all five model plants.

 6.1.4  MODEL PLANT FLOW RATES

A wastewater treatment plant design is based on both the raw
wastewater concentration and flow rate.   To assign a wastewater
                                199

-------
.1
vo
 a)
r-4

•8
H
                                                 o
                                                 in
                                  «•>©
«
u
•
a
«
                                             §
                                         eo   «
                                         e   o.
                                        •So
                                                 m
                                                 e
                                                 o
                4,1

                £

                •8
g.
o
                                                 •200

-------
                         Table  6-2

            UNTREATED  EFFLUENT CHARACTERISTICS
       USED IN THE DESIGN AND  COSTING OF WASTEWATER
      TREATMENT SYSTEMS  FOR  ETHANOL-FOR-FUEL PLANTS
Total

Dissolved

Total Suspended Solids  (TSS)

Total Kjeldahl Nitrogen  (TKN)

Ammonia (NH4-N)

Total Phosphorus

pH range
Concentration
   (mg/1)

    1,500

    1,100

      500

        3

        0

        7

     4-11
                            201

-------
flow rate to each of the five model plants, a general relation-
ship between wastewater flow rate and plant production capacity
was developed.  The data available for the development of model
plant flow rates are presented in Table 6-3.  As shown in Table
6-3  the data consist of average wastewater flow rate and
average ethanol production for a total of 18 facilities,
including both ethanol-for-fuel plants and beverage alcohol
plants.  Also shown in this table is the ratio of wastewater
flow rate to ethanol production.

The ratios of wastewater generated to ethanol produced are shown
plotted versus plant capacity in Figure 6-1.  These data  indi-
cate that the wastewater-to-ethanol ratio varies from 6.9 to
33.7 and does not increase or decrease as a function of plant
size.  This  indicates that the wastewater flow rate varies
linearly with plant production capacity.  The median was  se-
leeted to be used in relating model plant capacity to wastewater
flow.  Thus, since the median has a value of  16, each model
plant has a  wastewater flow  rate equal to 16  times the model
plant ethanol production capacity.

6.1.5  MODEL PLANTS SUMMARY

A summary of the characteristics of the model plants  is presen-
ted in Table 6-4.  Grain consumption  was  calculated  by  assuming
that  1,000  kilograms of corn can produce  0.37 cubic  meters of
ethanol.  This  is equivalent to  assuming  2.5  gallons of ethanol
per bushel  of corn, where  a  bushel  of corn  weighs  56 pounds.

Plants were  assumed to be  producing  alcohol only 330 days per
year;  the remaining  35 days  are  devoted  to  equipment cleaning
and shut-down  for maintenance and  repairs.   Thus,  in calculating
daily wastewater flow  from yearly  ethanol production, it  was
assumed  that the entire  yearly production of  ethanol was  Pro-
duced in only 330 days.   On  the  other hand, wastewater treatment
O&M costs were  calculated  on the basis of 365 days per year.
This assumes wastewater  flow continues even during periods of no
ethanol  production  (e.g.,  during plant cleanups).

 The wastewater flow rate for each of the model Plants was calcu-
 lated by assuming a wastewater-to-ethanol ratio of 16, as dis-
 cussed in the section on the flow prediction.  These flow rates,
 along with the concentration values given in Table 6-2, were
 used as the basis for the treatment systems costs presented in
 the following sections.

 in 1981, all beverage alcohol and ethanol-for-fuel producers
 sold the beer still bottom stillage, either as wet or dried
 by-products, for animal feed because of a viable market  for
 these high-protein by-products.  Further, the market for these
 bv-products was projected to double by 1985  to 1986  28).
 Therefore,  no cost for treatment or disposal is considered in
 the cost analyses for the stillage or by-product processing.
                                202

-------
                Table 6-3

PRODUCTION AND WASTEWATER GENERATION DATA FOR
     BEVERAGE AND ETHANOL-FOR-FUEL PLANTS
 Ethanol
Wastewater
 Ratio of Wastewater
Production to Ethanol
Plant
Code
A03
A06
A07
A10
E02
E04
EOS
E06
E07
EOS
E09
Ell
E12
E13
E15
E17
E18
E19
Production
(m3/day)
200
24
70
21
30
25
52
43
47
32
230
45
44
90
23
23
23
118
Production
(mVday)
2,650
170
1,290
340
760
400
830
610
570
610
7,650
1,100
820
1,320
380
380
350
1,550
Production
(Dimensionless)
13.3
6.9
18.5
16.2
25.0
15.7
16.0
14.2
12.0
19.1
33.7
24.4
18.6
14.7
16.2
16.5
15.3
13.1
                       203

-------





o
o
13
KQ
taB
00
o
gaS
?5 O
11
siw
0
o
H
H





32
30
28
26

24

22

20


13

16

14


12

10
8

6
EC
Se\i
_
_

©
- ' E°2Efl
•
'


""" ' .
•
E°8 ° °
PI 9 A07

.^AM <2?E15_0 	 	 f_i^LZ_ 	 , 	 , 	 ; 	
©E04 E05
© ©
E18 © E13
"" E06
O ©
_ E19
E07
—
_
0
£Q6 1 1 1 f II II I I
20   40'   60    80   100  120  140  160.  130  200  220

       ETHANOL PRODUCTION (m3/day)
              Figure g-i

RATIO OF WASTEWATER GENERATED TO ETHANOL
   PRODUCED VERSUS ETHANOL PRODUCTION
                  204

-------





















T
VO

Q)
JQ
to
£H






































CO
u
M
EH
'Ji
06
H
*^
o:
t^
3!
U
£4
z
g
i«4
Da
a
o
X
b
O
a:
f^
•£
JE
CO

















Q>

i
0
Cb
Q)
4J
10
»
0)
4J
(0
10


^^
>
•c

e
oooo
VO VO Ol fH
in co i^. <^
fH en e^

^
03
^
fH
<0
CT


o
^J
^^


u> en oo vo
fH ^* 9* ^
o o o fs







o
JJ
0
3

O
ft

0
(0
JC

M


i4
\
g
^^>
oooo
o o o o
TT CM f- 0
-JJ" r~ m os
,U E t- oo
*^




^
^
(0
D


O
fH
«•"


m 2 S S






^


O
fH
4J
Q
e
3
0)
C
o
c
•fH
j cr» t^ o
o? o -H m
CO VO "">

^




^
<0
^
0)
o
4J
id
fH.ua>
» c ja
•o  •*


0
0
fc
(M



O

in






0
0
o
in







o









o
{*)








pa
0
-0-


in


205

-------
The characteristics of the biosludge and the amount produced at
each facility were based on the model plant wastewater treatment
system design.  The biosludge from the secondary clarifier has a
solids concentration of 10,000 gTSS per cubic meter (one percent
solids).  Table 6-5 indicates the estimated sludge production
from the clarifier for the wastewater treatment options
developed for the five model plants.

6.2  TREATMENT OPTIONS FOR COST EVALUATION

6.2.1  WASTEWATER TREATMENT OPTIONS

There are a wide variety of treatment technologies which are
appropriate for the wastewaters produced by an ethanol-for-fuel
plant.  Technologies differ with respect to cost and  final
effluent quality.  Four different direct discharge treatment'
options were  selected  for detailed economic evaluation:

     Option 1 - Use of aerated  lagoons for secondary  treatment.

     Option 2 - Use of activated sludge for secondary treatment.

     Option 3 - Use of aerated  lagoons for secondary  treatment,
                followed by granular media filtration.

     Option 4 - Use of activated sludge for secondary treatment,
                followed by granular media filtration.

Aerated lagoons and  activated sludge are  both widely  used  in the
beverage  alcohol  and  ethanol-for-fuel  industries.   Granular
media  filtration  can  follow either aerated  lagoons or activated
sludge  and will bring  about significant additional suspended
solids  removal  (40 to 50 percent).

No treatment  options  have  been considered for indirect dis-
chargers (those who  discharge their wastewaters  to publicly
owned  treatment  works).   Based on  the  analytical data presented
 in Section 3, no  pollutants  are present  in  ethanol-for-fuel
wastewaters  which would upset or interfere  with the operation of
a publicly owned  treatment work.   However,  developers of an
 ethanol-for-fuel plant should consult  the general pretreatment
 requirements  contained in 40  CFR,  Part 403 to ensure  that such
 standards are met.

 6.2.2  SOLID WASTE TREATMENT OPTIONS

 As identified in Section 5.3, there were four methods practiced
 by the ethanol-for-fuel industry to treat and dispose of
 biosludge in 1981.

       1   Dewatering, stabilization, further dewatering; and
       either contract hauling, landfilling, or land  application.
                                 206

-------
                            Table 6-5

               BIOSLUDGE PRODUCED DURING WASTEWATER
                 TREATMENT FOR ETHANOL FACILITIES
Model Plant Alcohol
Production Capacity
   (10  qal/yr)
     11,400 (3)

     37,900 (10)

     75,700 (20)

    189,000 (50)

    454,000 (120)
Sludge Produced
	m3/Year

       8,180

      27,380

      54,750

     138,700

     328,500
Treated Sludge
 to Landfill
(1,000 kq/yr)

      139

      462

      945

    2,355

    5,640
                             207

-------
    2   Dewatering,  stabilization, lagooning; and either
        extract hauling, landfilling, or land application.

    3.   Dewatering,  inclusion in by-products.

    4.   Dewatering,  land application.-

For the purpose of performing the cost analysis, the ff«fc
^rLtment and disposal option  is selected since it is the most
cIpSrin?ens?vIPoptionPand would provide the most conservative
or "worse case" impact.

    actual treatment train  used in the cost  analysis consists of
$66 per metric ton of sludge.

6.3  CAPITAL AND OPERATION AND MAINTENANCE COSTS

6.3.1  WASTEWATER TREATMENT COSTS

Capital costs of wastewater treatment for all four treatment



the  site  of an existing ethanol-for-fuel plant.


     SS 2 rgSSE
                      .
 posal!  The annualized  cost of capital is not included.

 all costs are in March  1980 dollars.  Adjustments for inflation
 can be mfde using tSe EPA SCCT cost index which had a value of
 162.2 in March 1980.
 A schematic flow diagram for  treatment Options 1 and 3 is shown.
 tn Piaure 6-2   The aerated lagoon system  (Option 1) includes



 and a centrifuge for solids  dewatering.  The Option 3 system  is
 ?Sen?icIl to the Option 1 system except  that the effluent from
 t£rseconda?y clarifier receives additional treatment by
 granular media filtration.
                                 208

-------
                    Table 6-6

ASSUMPTIONS USED IN THE DESIGN OF THE SOLID WASTE
                 HANDLING SYSTEM
     Gravity Thickener (22)

     Solids Loading Rate (SLR):  20,000 g TSS/m2/day

     Underflow Concentration:    30,000 g TSS/m-*



     Aerobic Digester

     Reduction in Volatile Suspended Solids:  35 percent



     Centrifuge

     Solids Capture:  80 percent
                        209

-------














s
1
CO
H
CO
o
" ^
w SI
J w 2
5jH 3
SS 1
V • ^1
P^ •J M
0
0 300
JITJOi-l
W U^K
Bum
•^ f*%
r*» ^^
(M
C >i»^
§ So^o
«C *O O *H
AJ O C7^
1 '"'oiiNr *
I me

u a
I r1 '
e 5-^
l^il
lit!
w u •
OM «*•* !
1-1
P

rn g s s
f*» ** O "^
• • * ^
^ 4. •« -»



s °
i i- • °1
'- «N «



^
»
1
1 S S S g
« « « 2-
; — ~ — ^
<
•>
•S H
«
.
<



S "S | |» « 55
i^ 2 5 S.|B |-lc

u Sz '4^ 9
•S-g
H §
9*4
•«i|
U2L
CO
0) CU
M •
CJ>«4
4J 4J
^S-0
a S

1 0
r4 U
82
tri
4J
M "
= S
4J O
o oo
•rf e.
Ou fl>
e
0 0
h b
^4 Of
*00
•o^
CO 4J
Sm
Sij
ta
« 0
X u
•S*«
2^.
u
n a
0 «
CJ 4)
^d U
«e 5
••
«
4J
1


-------

















00
vo
4 M
OX
W
g
^gg
s
^^
CO
h
u»»
-JTi"
O JJ vo
0 3 O f
5"§^> M
u £«^
a. mo
•«* w
•*
1
i § §
oo to 0<
^ o^ o
M i-t CM




O^ 9
O JJ
£-DO —
jj 5 •
o«S **
— o
ut

O
1 • 1




X
B X»H
ajj. a
S^uTi M
u so
9 300
JJ Oh*"
^ICo
e- iT 7
XM
o^» a
e u vo
g 300
.ciaoi-)
W M -X
f* O



o o e
vo ir> vo

O
i - !





. tjl
g^^J
"O^TB S
0 3 O^C
js-aoo
jj osr>-i
fal b «
BUM X
•M

000
CM |M  jj •>*
9 ** a -o
b jj u e a
« U « 3S B
^ < <>^ o
M O.fc~4
E O E<-4 9
BO B60 BO3U
OO O*O OOBJJ
•^ 60 •* 3 «^ OCOJ-N

H &.J e.09 eu«J u fa.
O O o

§
O
CM





§
o"






o
vO
irt

S
f^







0
tM
^





Q)
M
1 5

tjjjzg
-» « jj

C 60*3 2
5-§gi
JJi-* hi w4
o09
^3
J
4J
o
3
14
e
B •
0-0
O V
n
ll
JJ B.
a
V 43
UJI
e
M"O
o 5
•§.
wri j_b
^^ **
If
jj a
ai
• jj
I*
o to
U B
31
^k 5i
If
B
52
* 0)
«-« a.
*«'
OO

O 0
OO JJ
£ «
* M B
« o
^6 W
5*3
sS
« Q
y
CO
vU (U
e a
O t)

ss
<5

• 9
«l
JJ

§
211

-------
                    »


                    u
















1
VO
ojc/a
Sw
M
H
W H
MnJ
CO M
OO
U»»•«
i 3C50
jj or*
U b -X
CM
b
"-jsr*
*o4jTi M
CO NO
0 900
U b°ix
b >
^J^s
1 *Ti a
« §00
fooe
"1511
t-<
j
£
c
4
c
i.
1
1

o o o o
CM VO !•«• •-<
-< GO i-^ 0^
«»> CM W CM

go
f>
i n vo vo f<>


,
o *o
1 P» 1 OO
i m i m


-3- ON "I ' O
m m vo i*«
^ CM ** «M

1 "S
•O *J "O •"
t) « «i a a a
7J ^ ^ «^ ^ ^4
B —4 « 13 M tJ
S u Com jj a a)
S 0 0)9X0 U9SC
4* < < i-* O  C ** 9 01^4 s)
co ceo eo9b c M9 b
OO O-O OOBJJ OT3 C 4J
•4«0 •»49 —4 00 0) 1-1 — 1 3 OJf-4
I U B Ui-4 U B f^— 1 4Ji-4 W-4
i a.>3 e»ca a. J C9 u. Q.W 13 b
000 0
                    U 0
                    12
                    1.
                    u m
                    §!H
                      4)
                    «i e

                    *:
                    u o
                    O M

                    1-4-O
                    5§
                    oL§"
                      9
                      U
                      fc.
                    SB
                     5-3
                      u
                     0«4
                     b O.
                     « «
                      O
                     a
                     4J Cl
                     gg «
                     9 «

                     "
                     |
212

-------
3
£
   £
   U
   u

   1
    §7
    •w4 ^
8.8-
I  °
I  £   -i-1
     ^
      -r21 S£
     sSji
s
s
    I
    U
    5

    !
    ii
       A  u 5T
       |   WO
                w  g
                « • •-
                 * -
                      ji
                                               en
                                               i
                                          vo


                                          
-------
Options 2 and 4 are illustrated in Figure 6-3.  Treatment up to
the aeration basin is identical with Options 1 and 3.  An
activated sludge system differs from an aerated lagoon due to
the use of sludge recycle which allows higher biomass concen-
trltions to be maintained in the aeration basin   Waste sludge
is sent to a gravity thickener and aerobic digester before
dewatering by9a solids centrifuge.  The Option 4 system differs
from the Option 2 system only in the use of flranular media
filtration for additional solids removal before discharge.

Cost estimates were developed using standard design techniques
and published cost data or direct vendor quotes.  Assumptions
used in the system design are presented in Table 6-10.  Cost
estimation assumptions are presented in Table 6-11.  Note that
all capital costs presented  in this document exclude interest
during construction.  The cost of interest during construction
variei as a function of  interest rate and is discussed in the
economic impact study (31).  For an interest rate of 10 percent
and an amortization period of  30 years, the cost of  interest
during conduction will  add  an additional 5 to 10 percent to the
capital costs  presented  here.

6.3.2  SOLID WASTE TREATMENT COSTS

Capital costs  for sludge handling for new and existing faci-
lities are  presented  in  Table  6-12.  Annual operation and
maintenance costs as  well as energy requirements  for the  treat
ment and disposal of  solid waste  are also presented.  Table 6-5
presented  thl  amount  of  treated  sludge  in metric  tons per year
which  must  be  hauled  for landfill.
 The only solid waste which has an economic imPac V°Vn
 production facility is the biosludge from wastewater treatment.
 Therefore, the costs associated with solid waste  handling have
 been included in the wastewater treatment costs.

 6.4  NON-WATER QUALITY ASPECTS

 The nonwater quality aspects of the presented treatment options
 inclCde any solid waste disposal, air pollution,  or energy con-
 sumption problems that might be associated with the treatment
 ootions   The Agency gives consideration to nonwater quality
 ilsues in order lo minimize cross-media conflicts; for example,
 creatinq an air pollution problem while solving a water pol-
 lllion IroSlem. Energy conservation is also a national Priority
 and the Agency examines the energy requirements of each treat-
 ment option to determine  if a significant increase in energy
 required per pound of product would result.

 Solid Waste Disposal.  All four of the wastewater treatment
 options previously presented will produce significant quantities
 of biological sludge.  This sludge has been determined to be
                                 214

-------
g
4*
*
             *  g
             J • -S
             « "«^ 4J

             I1
                       j:
                                                                   .0
                                                                    CM
                                                                    i
                                                                 CO
                                                                      S3
                                                                 £  H
                                                                 toO  &4
                                                                    0
                                                                   en
S
6
2
                       215

-------
                           Table 6-10

                ASSUMPTIONS USED IN SYSTEM DESIGN
Preliminary treatment consists of bar screening, grit removal,
and fTS measurement.  These units were sized based on maximum
flow rate.

p.v, wastewater pumping capacity was set to provide a firm pumping
capacity equal to tne maximum flow.

Eaualization basin volume is set equal to 20 percent of total
dai?y llow volume.'   In the activated sludge system a concrete
basin was used.  The aerated lagoon system uses a lined earthen
basin.
 na lim  f    system are  included.  Average chemical doses over
a  24-hour period are  200 mg/1  CaO  and 47 mg/1 H2SO4.
Nutrient addition  is  necessary because  wastewater  is  high  in
     and low  in both  nitrogen  and  phosphorus.   Required  chemi-
     dosaoes are calculated  on  the  basis of  cell growth by  assum-

                         ^^^^
 coefficient equals 0.45 mg VSS per mg
 kind often sttles porly.  As an aid to settling, secondary
 ciaririer i! dosel w?th 17 mg/1 of ferric sulfate (^2804).
 Ae?aJion system was designed by considering oxygen demand and
 mixing Requirements.  A diffused aeration system was selected and
 75 cubic meters of air were applied for each kilogram of BOD5
 removed.
 Aerated lagoon system was designed using a first order
 model with a kinetic constant value of 2 day A.  This
 in a hydraulic residence time of 25 days.  The aerated lagoon
 consists of a lined earthen basin with surface aerators.  A
 cemlnf circufar clarifier is used after the lagoon  for suspended
 soTiSs removal.  Aerators transfer 2.1 pounds oxygen per
 horsepower-hour .
                                  216

-------
                      Table 6-10  (Continued)

                ASSUMPTIONS USED  IN SYSTEM DESIGN


Sludge handling system consists of sludge thickener, aerobic
digester, and solids centrifuge for the activated sludge system.
Sludge thickener size for solids loading of 20 kilograms of TSS
per square meter per day.  Aerobic digester achieves 35 percent
volatile suspended solids reduction.  Centrifuge has 80 percent
solids capture and produces a final sludge with 20 percent
solids.

Granular media filtration used filtration rate of 2 to 5 gallons
per minute per square foot.
                               217

-------
                          Table 6-11

              ASSUMPTIONS USED IN COST ESTIMATION
1.  Date basis for all costs is March 1980 at which time the EPA
    SCCT Cost Index had a value of 162.2.

2.  Cost estimates were developed from direct vendor quotes,
    material take-off calculations, and the following published
    data sources:  Benjes, 1980; Conway and Ross, 1980; Gulp,
    1980; EPA a, 1975; Gumerman et. al., 1979; and Patterson and
    Banker, 1971.

3.  Yardwork is 14 percent of total installed unit process
    costs.

4.  Engineering and contingency are each 10 percent of the total
    direct construction cost.

5.  Land cost was assumed to be $15,000 per acre for aerated
    lagoons and $30,000 per acre  for activated sludge.

6.  Working capital was assumed to be  20 percent of annual O&M
    cost.

7.  Labor wage is  $11.00 per hour direct plus 15 percent for
    indirect  costs  (medical, insurance).   Net rate  is  $12.65 per
    hour.

8.  Electricity costs $0.035 per  kilowatt-hour.

9.  Chemical  costs  are as  follows:

                Chemical
     Lime  (pebble  quicklime)
     Sulfuric Acid
     Phosphoric Acid (75% solution)
     Ammonia (Aqua-ammonia,  30%
     Ferric Sulfate, 94%
$  65/ton
$  70/ton
$ 460/ton
$ 225/ton
$ 146/ton
     All costs above include shipping to the plant site.

10.  Sludge disposal costs $60/ton including hauling from plant
     site to landfill.
                                 218

-------
>t
Jj — '
0 >
4J.C
0 S
a> us

o
CM
m
r-
o
ft

o
o
CO
_
^*
fl

O
o
00
CM
CM

O
o
VO
00
^*
p*

o
o
o
0
*H
M.
                                                                                          O
                                                                                          0)
                £  to
                ««  O'  .
                O Ow-
                             O
                             tn
r-
m
      o
      o
      ts
                                                      co
O
z
z
<
X

ta
H
CO
 I


 a)    2
•H
JD    a
 (0    M


      co

      Cu
      O
CO
o
U








4J
to
0
u

ft
(0
'a
IQ
u







n
0)
•1-1
4J
•H
u
(0
ba
O
•H
4J
(0
•rH
M
U




o o o o
o o o o
Tp O ••* CTt
^> oo ve co
^H CO ft fl
m vo OT\ PO
ft
to-






to
Q>
•1-1
4J
•H
ft
•I-l
u
fl
Cu
0)
Z
0)
M —
•H >
co a
C £
(Q £


o o o o
o o o o
c-» ft oo en
en* en CM en
o ^* PO m
^« m r- o
i— t
CO-





PO O O O
ft CM m





o
o
%
00
r-
CM









O
O
°1
m
en
^j
^^





o
o
*"*
                                                                                                e
                                                                                                o>
                                                                                               •d
                                                                                                CO
                                                                                                0)
                                                                                               •o

                                                                                               4J
                                                                                                C

                                                                                                i
                                                                                               4J
                                                                                                (0
                                                                                                0)
                                                                                                f
                                                                                               4J
                                                             (U
                                                             4J
                                                             (0

                                                             0)
                                                             4J
                                                             to
                                                             (0
                                                                                          Q>

                                                                                         4J
                                                            •O
                                                             «)
                                                            •o
                                                            •H
                                                             >   •
                                                             O  (0
                                                             U  0>
                                                             a-*
                                                                o»
                                                             e  o
                                                             (I) iH
                                                             
                                                                                         4J  nj
                                                                                         C  Q)
                                                                                         U
                                                                                         •i-4  Q)
                                                                                         <44 4J

                                                                                         «W  tO
                                                                                         3  flJ
                                                                                         CO  »
                                                                                         •K
                                                    219

-------
nonhazardous and, in some cases, can be recovered and sold with
the by-product grains.  If this sludge is not recovered, it is
usually dewatered and stabilized before contract hauling to a
landfill.  No further wastes are generated by sludge treatment.
Wastewater overflows from the gravity thlc*en*%and solids cen-
trifuge used to dewater the sludge are sent to the aeration
basin lor treatment.  Also, stabilization of the sludge reduces
any odors emitted from the thickened sludge.  Section 3.-7 pre-
sented a detailed discussion of solid wastes associated with
ethanol-for-fuel production and methods of recovery, treatment,
and disposal.

Air Pollution.   No  serious air pollution problems are -antici-
pated as a result of implementing any of the control techno-
logies evaluated in this cost analysis.  Potential odor P^lems
could be encountered in operating secondary biological treatment
Systems, but  this should not be a serious problem when systems
arl operated  properly.  Section 3.6 presented a detailed dis-
cussion  of air  pollution problems associated with ethanol-
for-fuel production.

Energy Requirements.   Table 6-13 presents energy requirements
for treatment options  1 through 4.  Although energy  ^u^ents
constitute a  major  portion of the O&M costs of  the treatment
system,  none  of these  treatment systems  would result in a  signi-
filant  increase in  the overall  energy requirements of  a typical
ethanol-for-fuel plant.
                                  220

-------
H





CO
is
s
Sco
^S ^
l_^ 5** ^^
11 1
Qr^J «^
S* 1
OS .1
>» B3 •*
095 ,
p"* u
ca |

H H
•< CO
&M
Sx
H W
CO
)
fc^^1
C ^S^^
o-^. «
f4 *<")fO Ct(
0 4J •
B a xo
Jg 300
JJ Of^"1*
"£So




5 1. -S 1
o* 53* -T o"
<-• — f-t ^<
SI
h*%*
-If"
O *J •
£ Sj _*
5-88-
W b «X
?l Ift



b
B X-£
f-«
Bu« X
^^
B
0
 S o i»
»-• <-4 CM <-T



3 2
v * "« « « a
4J ^ ^ ^4 S ^2
g ^ « «o 5 ?
b JJ bOBW 4J CO W
Jl ^ ^5S§ ^5si
"B "*« "B^? ^^J"
co coo eosh e S"D u
O O O T3 O 0 C 4J O *O C fcl
*J S? £— Scfb^ i5 S52
                                221

-------
                             GLOSSARY
absolute ethanol:  Dehydrated ethyl alcohol of the highest proof
     obtainable  (200° proof), also called anhydrous ethanol.

absorption:  The taking up of one substance into the body of
     another.

acid hydrolysis:  A kind of cellulose-to-sugar conversion
     process which uses acid (sulfurous acid) to break down the
     cellulose.  Urban waste and vegetable residues can be
     turned into ethanol by this process.

activated sludge:  Sludge floe produced in raw or settled
     wastewater  by the growth of zoogleal bacteria and other
     organisms in the presence of dissolved oxygen and accumu-
     lated in sufficient concentration by returning floe
     previously  formed.

activated sludge process:  A biological wastewater treatment
     process in which a mixture of wastewater and activated
     sludge is agitated and aerated.  The sludge is subsequently
     separated from the treated wastewater (mixed liquor) by
     sedimentation and wasted or returned to the process as
     needed.

adsorption:  The adherence of a gas, liquid, or dissolved
     material on the surface of a material.

aerated  lagoon:  A natural or artificial wastewater treatment
     pond in which mechanical or diffused-air aeration is used
     to  supplement the oxygen supply.

aerobic:  A condition  in which  free, elemental oxygen is
     present.

alcohol:  A class of organic chemicals composed of carbon,
     hydrogen,  and oxygen which  include methanol, ethanol,  and
     other alcohols; most all alcohols will produce a flame when
     ignited  in air.

aldehyde (Webster):  Any of  various  highly reactive compounds
     typified  by acetaldehyde and  characterized by the group
     CHO.  A volatile  fluid  obtained by  the  oxidation of
     alcohol.

alkalinity:   Alkalinity  is a measure of  the  capacity of water to
     neutralize an  acid.

anaerobic:   A condition  in which free, elemental  oxygen  is
     absent.
                                222

-------
 anaerobic fermentation:   The process whereby chemicals (espe-
      cially starches and sugars contained in many agricultural
      crops) are broken down by bacteria and yeasts in the
      absence of free oxygen to produce alcohols.

 anhydrous:   Means  "without water."   The ethanol contained in
      gasohol is usually  anhydrous;  even very small amounts of
      water  in ethanol may cause separation of the ethanol
      gasoline mixture.

 apparent proof: The equivalent'of  proof for ethyl alcohol
      solutions containing ingredients  other than  water.

 ATF (Bureau of Alcohol,  Tobacco and Firearms):  Federal agency
      responsible for the licensing  and regulation of  alcohol
      production and  sales.   A division of  the Department  of
      Treasury.

 backwashing:   The  operation of cleaning a  filter  by reversing
      the  flow of liquid  through it  and washing  out matter
      previously captured in it.

 bar rack:   A screen  composed of parallel bars,  either  vertical
      or  inclined,  placed in  a  waterway to  catch debris.

 barometric  condenser:  See  condenser,  barometric.

 basin:  A natural  or  artificially created  space or structure
      which  has  a shape and  character of confining material that
      enables  it to hold  water.

 beer:  The  liquid  containing mash which has been fermented in an
      ethanol-for-fuel plant.   It contains  10 to 12 percent
      ethanol.

 beer  still:  A distillation column in which the beer is stripped
      of the ethanol, producing  an 80 percent ethanol product.

 benzene recovery column:  A column in which the benzene and
     ethanol are stripped from an ethanol/water rich inlet.  The
     benzene and ethanol are recycled to the dehydration column
     while the residual water is sent to the waste treatment
     plant.

biochemical:  Pertaining to chemical change resulting from
     biological action.

bio-degrade:  To biologically reduce the complexity of a chemi-
     cal compound or substance by splitting off one or more
     groups or large component parts; decompose.
                               223

-------
bio-dearadability:  The destruction or mineralization of either
     natural or synthetic organic materials by microorganisms.

biological filter:  A bed of stone or other medium through which
     wastewater flows or trickles that depends on biological
     action for its effectiveness.

biological wastewater treatment:  Forms of wastewater treatment
     in which bacterial or biochemical action is intensified to
     stabilize, oxidize, and nitrify the unstable organic matter
     present.  Intermittent sand filter, contact beds, trickling
     filters, and activated sludge processes are examples.

biomass:  Living matter, vegetation or any plant material, now
     in a state of decay, including animal and human waste, that
     may be used to produce energy.

BOD  (Biochemical Oxygen Demand):  A semiquantitative measure of
     bioloqical decomposition  of organic matter  in a water
     sample.   It  is determined by measuring the  oxygen required
     by microorganisms to oxidize the  contaminants of a water
     sample undlr  standard  laboratory  conditions.  The standard
     conditions include  incubation  for five days at  20 C.

BOD  load:   The BOD content, usually  expressed  in mass or weight
     per unit  time, of wastewater.

boiler blowdown:   Discharge from a  boiler  system designed  to
     prevent  a buildup of dissolved solids.

boiler feedwater:  Water used to generate  steam in  a boiler.
     This  water  is usually  condensate, except  during boiler
      startup,  when treated  fresh water is  normally  used.

brine:  Concentrated salt solution remaining  after  removal of
      distilled product.

 brix:   A reading  on a hydrometer scale which  represents weight
      percentage of sugar in solution at a specified temprature.

 bulking sludge:   An activated sludge that settles poorly because
      of a low density floe.

 bushel:  The weight of grain  contained in a bushel varies by
      industry as follows:  (a)  Barley = 22 kg  (48 Ib)
       (b)  Malt = 15 kg (45 Ib)  (c)  Distillers Grain = 25 kg
       (56 Ib).

 capital costs:  Costs which result in the acquisition of, or the
      addition to, fixed assets.
                                224

-------
cellulosic:  Refers to chemicals contained in crop stalks,
     forest residues, and substantial portions of urban wastes;
     treatment of cellulosic materials with acids or enzymes
     will yield fermentable sugars which can be converted to
     alcohols.

clarification:  Removing undissolved materials from a liquid by
     settling, filtration, or flotation.

clarifier:  A unit of which the primary purpose is to reduce the
     amount of suspended matter in a liquid.

coagulation:  In water and wastewater treatment, the destabili-
     zation and initial aggregation of colloidal and finely
     divided suspended matter by the addition of a floe-forming
     chemical or by biological processes.

COD (Chemical Oxygen Demand):  Its determination provides a
     measure of the oxygen demand equivalent to that portion of
     matter in a sample which is susceptible to oxidation by
     strong chemical oxidant.
column bottoms:  The less volatile component in a distillat/ion
     column comes off the bottom while the more volatile
     component is vaporized and comes off the top.  The less
     volatile component makes up the column bottoms.

comminute:  To reduce to minute particles or fine powder; to
     brealc up, chip, or grind; to pulverize.

composite sample:  A combination of samples taken at selected
     intervals to minimize the effect of the variability of
     individual samples and are proportional to the flow at time
     of sampling.

concentration:  The amount of a given substance in a unit
     volume.  For wastewater, normally expressed as milligrams
     per liter (mg/1).

condensate:  Water resulting from the condensation of vapor, as
     in an evaporator.

condenser:  A heat exchange device used for condensation.

   barometric:  Condenser in which the cooling water and the
                vapors are in physical contact; the condensate
                is mixed in the cooling water.

   surface:     Condenser in which heat is transferred through a
                barrier that separates the cooling water and the
                vapor.  The condensate can be recovered sepa-
                rately.

                               225

-------
 continuous fermentation:   A fermentation process  in which  the
      yeast is  separated from the  fermented  mash and recycled to
      the fermenters.

 conversion ratios:

 1.   1 bushel of  corn  yields 2.73  gallons of 190 proof  ethanol.

 2.   1 bushel of  corn  yields 2.55  gallons of 200 proof  ethanol.
 3.   1 barrel = 42 gallons.
 4.   1 bushel of  corn  weighs 56 pounds.
 5.   1 gallon of  ethanol weighs 6.6 pounds.
 6.   1 ton of crop residue  contains .8 tons  of  fermentable  sugar,,
 7.   1 ton of fermentable sugar yields .5 tons  of  200 proof
     ethanol.
               i
 cooling  tower  blowdown:  Discharge from  a cooling tower system
      designed  to prevent a  buildup of dissolved solids.

 decanting:  Separation  of  liquid  from solids by drawing off the
      upper layer after  the  heavier material has settled.

 dehydration:   The removal  of  all  water from the ethanol.   This
      process must be  accomplished by altering  the azeotrope by
      the  addition of  a  third  compound.

 dehydration agent:  That compound used to alter the water/
      ethanol azeotrope  to permit  the dehydration of the
      ethanol.

 denaturant:  A material added to ethanol  to destroy its
      character as beverage.

 denatured ethanol:  Ethanol which has been denatured pursuant to
      completely  denatured ethanol formulas prescribed by federal
      regulations.  Unfit for human consumption.

digestion:  See  sludge digestion.

dissolved solids:  See solids.

distillate:  Condensed vapors from the solution which form the
     product of distilling.

Distiller's Dried Grains (DDG):   A high protein (25 to 30
     percent)  by-product of the  grain fermentation process  which
      is used for animal feed; large scale ethanol  production
     would substantially increase DDG by-products.

distillation:   .A process of evaporation  and  recondensation  used
     for separating liquids into various fractions according to
     their boiling points  or boiling  ranges.

                                226

-------
D.O.  (Dissolved Oxygen):  A measure of the amount of free oxygen
      in a water sample.  It is dependent on the physical, chemi-
      cal, and biochemical activities of the water sample.

DOE:  Department of Energy.

DOI:  Department of Interior.

doubling:  Redistilling spirits to improve strength and flavor.

"effect":  In systems where evaporators are -operated in series
      of several units, each evaporator is known as an effect.

EGD:  Effluent Guidelines Division

energy economy:  Heat release; Btu's per gallon; often expressed
      in miles/100,000 Btu's.

entrainment:  The entrapment of liquid droplets in the water
      vapor produced by evaporation.

enzyme:  Catalytic chemical substances responsible for alcoholic
      fermentation.

enzyme hydrolysis:  A technology which uses enzymes in yeast and
     mildew to break down cellulose to sugar.

EPA:  United States Environmental Protection Agency.

equalization basin:  A holding basin in which variations in flow
     and composition of a liquid are averaged.  Such basins are
     used to provide a flow of reasonably uniform volume and
     composition to a treatment unit.

ethanol (ethyl alcohol):  The common name for the hydroxyl deri-
     vative of the hydrocarbon ethane  which is also known as
     carbinol, ethyl hydroxide, grain alcohol, fermentation
     alcohol, cologne spirits, and spirits of wine.

ethanol-for-fuel plant:  Those commercial-size (greater than one
     million gallons per year) facilities that convert biomass
      (via fermentation-)- to ethanol for use as a fuel.

evaporator:  A closed vessel heated by steam and placed under a
     vacuum.   The basic principle is that syrup enters the
     evaporator at a temperature higher than its boiling point
     under the reduced pressure, or is heated to that  tempera-
     ture.  The result is flash evaporation of a portion of the
     liquid.
                               227

-------
excise tax exemption (gasoline)s  P.O. 95-618 exempts gasoline
     used for blending with alcohol from 4 cents Federal excise
     tax.  Many states have similar exemptions.

experimental permit:  ATF temporary permit which allows experi-
     mentation or development of materials for the production of
     distilled spirits, processes for the production or distil-
     lation of distilled spirits or industrial use of distilled
     spirits.  Ethanol produced cannot be sold or given away.

feedstock preparation:  The process by which the raw material is
     converted to a saccharified mash which can be fermented.
     The process varies according to the feedstock used.

feed wort:  A mixture of cane and beet molasses that is diluted
     with water, clarified, sterilized, and pH adjusted, and
     used to provide carbon, sugar, and other nutrients
     necessary for yeast growth.

fermentation:  The production of ethanol and carbon dioxide from
     fermentable carbohydrates by the action of yeast.

fermentation ethanol:  Ethanol obtained by the fermentation of
     renewable biomass feedstocks.

FGD:  Flue Gas Desulfurization.

filter:  A device or structure from removing solid or colloidal
     matter from a  liquid.  The filtering medium consists of a
     granular material, finely woven cloth, unglazed porcelain,
     or  specially prepared paper.

filter press:  In the past the most common type of filter used
     to  separate solids from sludge.  It consists of a simple
     and efficient  plate and frame filter.

fixed beds:  A filter or adsorption bed where  the entire media
     is  exhausted before any of the media is cleaned.

flocculant:  A substance that  induces or promotes fine particles
     in  a colloidal suspension to aggregate into small lumps,
     .which are more easily removed.

flotation:  The raising of suspended matter to  the surface of
     the liquid  in  a tank  as scum - by aeration, the  evolution
     of  gas, chemicals, electrolysis, heat, or  bacterial de-
     composition -  and  the subsequent removal  of the  scum by
     skimming.

fusel oil:  An inclusive term  for heavier, pungent-tasting
     alcohols, principally anyl and butyl alcohols,  removed
     through rectification.

                                228

-------
Gasohol:  A registered trademark held by the State of Nebraska
     for a fuel mixture of 10 percent anhydrous ethanol and 90
     percent unleaded gasoline; it is often used to mean any
     mixture of alcohol and gasoline to be used for motor fuel.

germicidal treatment:  Any treatment involving killing of micro-
     organisms through the use of disinfecting chemicals.

GPD:  Gallons per day.

GPM:  Gallons per minute.

granular media filtration:  A filtration process which consists
     of passing wastewater through a packed bed of granular
     material with the solids in the wastewater depositing onto
     the granular media.

heads:  A distillate containing a high percentage of low-boiling
     .components such as aldehydes.

hydrolysis:  The chemical splitting of a bond which results in a
     new compound and water.

hygroscopic:  Tending to absorb moisture from the atmosphere.

impoundment:  A pond, lake, tank, basin, or other space which is
     used for storage of wastewater.

industrial wastes:  The liquid wastes from industrial processes,
     as distinguished from sanitary wastes.

industrial wastewater:  Wastewater in which industrial wastes
     predominate.

ion exchange:   A chemical process in which ions from different
     molecules are exchanged.

ion exchange resins:   Resins consisting of three-dimensional
     hydrocarbon networks to which are attached ionizable
     groups.

ketone (Webster):  An organic compound with a carbonyl group
     attached to two carbon atoms.

Kraus Process:   A modification of the activated sludge process
     in which aerobically conditioned supernatant liquor from
     anaerobic digesters is added to  activated sludge aeration
     tanks to improve the settling characteristics  of the sludge
     and to add an oxygen resource in the form of nitrates.

lagoon:   A pond containing raw or partially treated wastewater
     in which aerobic and anaerobic stabilization occurs.

                               229

-------
lean fuel mixture:  An excess of air in the air/fuel ratio.
     Gasohol has a leaning effect over gasoline because the
     ethanol adds oxygen to the system.

mash:  Grain which has been steeped in hot water.  During the
     mashing process, the starch in grain is converted to
     fermentable sugars.

mashing:  The process involving cooking, gelatinization of
     starch, and conversion, changing starch into grain sugar.

membrane technology:  Works by a process of osmosis.  In a
     highly simplified explanation, the membranes act as a
     screen or filter, only allowing certain substances to pass
     through.  A membrane would allow ethanol to pass through
     while stopping stillage, sugars, and water.  The final
     result of membrane technology is two hundred proof ethanol
     which is less expensive to produce.

metabolism:  The sum of the processes concerned in the building
     up of protoplasm and its destruction incidental to life;
     the chemical changes in living cells by which energy is
     provided for the vital processes and activities and new
     material is assimilated to repair the waste.

raethanol (methyl alcohol):  An alcohol which can be produced by
     destructive distillation of wood or urban wastes and used
     as a gasoline extender; most of the methanol used today is
     produced from natural gas; coal may also be converted into
     methanol; also known as wood alcohol or methyl alcohol;
     methanol when mixed with gasoline, tends to separate from
     the gasoline under certain conditions; methanol will also
     enhance gasoline octane.

ug/1:  Micrograms per liter (equals parts per billion (ppb) when
     the specific gravity is unity).

MGD:  Million gallons per day.

rag/1:  Milligrams per liter (equals parts per million (ppm) when
     the specific gravity is unity).

mixed liquor:  A mixture of activated sludge and organic matter
     undergoing activated sludge treatment in the aeration tank.

mixed media filtration:  A combination of different materials
     through which a wastewater or other liquid is passed for
     the purpose of purification treatment, or conditioning.

moisture:  Loss in weight due to drying under specified condi-
     tions, expressed as percentage of total weight.

moisture content:  The quantity of water present in a sludge
     expressed in percentage of net weight.

                              230

-------
molassess  A dark-colored syrup containing sugar produced as a
     by-product in cane, citrus, and beet sugar processing and
     in the production of citrus concentrates.

mostos:  The stillage produced by cane and citrus molasses
     distillers which has less nutritional value than grain
     stillage.

multiple effect evaporation:  The operation of evaporators in a
     series.

municipal sewage:  The spent water of a community.  See waste-
     water.

MSW (Municipal Solid Waste):  In regard to this document the
     term refers to waste with potential for conversion to
     methanol.,

net BOD:  The amount of BOD added by a process; the difference
     between the BOD load of a plant's discharge and its intake.

neutralization:  The process of pH adjustment which results in a
     final solution pH of 7.  Depending on the influent solu-
     tion's pH, either acid or base is added to achieve a
     neutral solution.

noncontact wastewaters:  Those wastewaters such as spent cooling
     water which are independent of the manufacturing process
     and contain no pollutants attributable to the process.

NOX:  Nitrogen Oxides.

NPDES:  National Pollutant Discharge Elimination System.

NSPS:  New Source Performance Standards.

nutrients:  The nutrients in contaminated water are routinely
     analyzed to characterize the food available for micro-
     organisms to promote organic decomposition.  They are:.

          Ammonia Nitrogen (NH3), mg/1 as N Kjeldahl Nitrogen
          (ON), mg/1 as N Nitrate Nitrogen (NOs), mg/1 as N;
          Total Phosphate (TP), mg/1 as P Ortho Phosphate (OP),
          mg/1 as P

O&G (Oil and grease):  Wastewater parameter measuring nonsoluble
     organic fraction.

Operating Permit for Distilled Spirits Plant:  ATF permit
     required if the distilled spirits plant will produce
     ethanol only for nonbeverage industrial use (e.g., a
     Gasohol plant).


                              231

-------
osmotic pressure:  The pressure associated with the diffusion of
     substances through a semi-permeable membrane, such as a
     cell membrane.  The osmotic pressure is related to the
     molar concentration of the medium and the absolute
     temperature.

OSW:  Office of Solid Waste (EPA).

ozonation:  The saturation of a solution with ozone, resulting
     in disinfection of the solution.

PCTM:  Pollution Control Technical Manual.

pH:  pH is a measure of the negative log of hydrogen ion
     concentration.

pitching:  Adding yeast to a solution to cause fermentation.

PNA:  Polynuclear Aromatics.

polluted wastewaters:  Those wastewaters containing measurable
     quantities of substances that are judged to be detrimental
     to receiving waters and that are attributable to the
     process.

polyelectrolytess  Usage of this term in a document refers to a
     coagulant aid consisting of long chained organic molecules.

POTW:  Publically Owned Treatment Works.

ppb:  parts per billion.  See micrograms/liter.

ppm:  parts per million*  See milligrams/liter.

precoat filter:  A type of filter in which the media is applied
     to an existing surface prior to filtration.

preliminary filter:  A filter used in a water treatment plant
     for  the partial removal of turbidity before  final
     filtration.

preliminary treatment:  Those processes used to protect or opti-
     mize the  performance of downstream units at  a wastewater
     treatment facility.  Preliminary treatment provides no
     pollutant removal; it is a control system to ensure effec-
     tive operation.  The processes  used are bar  screening,
     equalization, and neutralization.

primary  treatment:  The removal of suspended solids by physical
     means.  The processes used are  coarse screening and sedi-
     mentation,  which  remove  approximately 10 percent of the
     influent  suspended solids*

                               232

-------
proof:  Alcoholic content of a liquid at 16°C  (60°F), stated as
     twice the percentage of ethanol by volume  (United States
     definition).

proof gallon:  A standard U.S. gallon containing 50 percent
     ethanol by volume.

raw wastewater:  Wastewater prior to treatment.

reboiler:  A kettle used to heat the bottoms of a column which
     will be recycled to the column inlet.

rectification:  Usually referring to the redistillation of
     certain goods for the purpose of increasing purity,
     concentration, or quality.

returned sludge:  Settled activated sludge returned to mix with
     incoming wastewater.

rich fuel mixture:  An excess of fuel in the air/fuel ratio.

ridge and furrow irrigation:  A method of irrigation by which
     water is allowed to flow along the surface of fields.

rotary vacuum filter:  A rotating drum filter which utilizes
     suction to separate solids from the sludge produced by
     clarification.

rotating biological contactor (RBC):  A set of molded disks that
     have a thin biological film growing on the surface.  These
     disks are partially submerged in a cylindrical tank and are
     rotated.  RBC's are used for secondary treatment.

roughing filter:  (1) A wastewater filter of relatively coarse
     material operated at a high rate to afford preliminary
     treatment, (2) For water treatment, see preliminary filter.

sanitary sewage, sanitary wastewater:   Liquid wastes from
     residences or commercial establishments, as distinguished
     from industrial wastes.

secondary wastewater treatment:   The treatment of sanitary
     sewage by biological methods after primary treatment by
     sedimentation, usually considered to remove 90 percent or
     more of the influent BOD.

settleable solids:  See solids.

settlings:  The material which collects in the bottom portion of
     a clarifier.
                               233

-------
settling pond:  See clarifier.

sewerage:  System of piping, with appurtenances, for collecting
     and conveying wastewater from source to discharge.

skimming:  The process of removing floating grease or scum from
     the surface of wastewater.

sludge:  The accumulated solids separated from wastewater during
     treatment.

sludge cake:  Sludge that has been dewatered to a moisture
     content of 60 to 85 percent.

sludge dewatering:  The process of removing the moisture content
     of a sludge to such an extent that the sludge is spadable.

sludge digestion:  The process by which organic or volatile
     matter in sludge is gasified, liquefied, mineralized, or
     converted to a more stable organic matter through the
     activities of either anerobic or aerobic organisms.

sludge drying:  The process of removing a large percentage of
     moisture from sludge by  drainage or evaporation.

sludge thickening:  The process of increasing the solids
     concentration of a sludge, but not to such an extent that
     the sludge is spadable.

sludge handling:  The transport, storage, treatment, and
     disposal of  sludge.

slurry:  A watery mixture or  suspension of insoluble matter.

solids:  Various  types of solids are  commonly determined on
     water samples.  These  types of solids are:

     Total Solids (TS):  The  material left after  evaporation and
                         drying of a  sample at  100°  to 105°C.

     Dissolved Solids  (TDS):   The difference between suspended
                               solids  and  total  solids.

     Volatile Suspended  Solids (VSS):   Organic  matter  which  is
                                        lost when  the sample  is
                                        heated to  550°C.

      Settleable  Solids  (SS):   The materials which settle  in  an
                               Imhoff  cone in one  hour.
                                234

-------
     Total Suspended Solids  (TSS):  The material  removed from a
                                    sample filtered through a
                                    standard glass fiber filter
                                    and dried at  103° to 105°C.

 solvent extraction:  The stripping of a component of a solution
     by use of a solvent.

 SOX:  Sulfur Oxides.

 spadable sludge:  Sludge that can be readily forked or shoveled,
     ordinarily under 75 percent moisture.

 spent beer:  Residual nutrients separated from harvested yeast
     by centrifugal separation.

 spent grains:  Residual grains following their utilization in
     the processing of ethanol.  These by-products are usually
     marketed as animal feeds.

 spent sulfite liquor (SSL):  The lignins/sugar solution
     separated from the fibrous cellulosic material in wood
     preparation.

 spray evaporation:  A method of wastewater disposal in which
     water is sprayed into the air to expedite evaporation.

 spray irrigation:  A method of irrigation by which water is
     sprayed.

 stillage (or still slops):   The waste dealcoholized liquid from
     the beer stills.

 synthetic ethanol:   Ethanol produced from ethylene as opposed to
     fermentation ethanol,  which is obtained from the fermenta-
     ation of renewable biomass sources.

 tax-free alcohol:  Pure ethyl alcohol withdrawn free  of  tax for
     government,  for science or for humanitarian reasons.   It
     cannot be used in foods or beverages.   All purchases  out-
     side of the government must obtain permits, post bonds,  and
     exert controls upon storage and use  of  tax-free  alcohol.

tax-paid alcohol:  Pure ethyl alcohol which  has been  released
     from Federal bond by payment of the  Federal tax  of  $21.00
     per gallon at 200 proof or $19.95 per gallon at  190 proof.

tertiary treatment:   The processes which  follow secondary  treat-
     ment in a wastewater treatment facility.   These  processes
     provide further removal of pollutants and  are granular
     media filtration,  land application,  and air flotation.
                               235

-------
TOG:  Total Organic Carbon.

TSP:  Total Suspended Particulates.

TSS:  Total Suspended Solids.

VOC:  Volatile Organic Carbon.

volumetric fuel economy:  Miles per gallon.

whey:  The water part of milk separated from the curd in the
     process of making cheese; it is a by-product produced
     commercially in large quantities and can be used as a
     fertilizer, animal feed or in the production of ethanol.

yeast:  Microscopic unicellular organism responsible for
     alcoholic fermentation.
                                236

-------
                           REFERENCES


 1.  Potter, F. L., U.S. Alcohol Fuels Industry Data Base,
     Information Resources Incorporated, Washington, DC,  (1984).

 2.  Cheremisinoff.  Gasohol for Energy Production.  Ann  Arbor
     Science, Ann Arbor, Michigan,  (1979).

 3.  U.S. DOE.  First Annual Report to Congress on the Use of
     Alcohol in Motor Fuels.  Office of Alcohol Fuels.
     Washington, D.C., April 1, 1980.

 4.  U.S. DOE.  The Report of the Alcohol Fuels Policy Review.
     Washington, D.C., DOE/PE-0012, June 1979.

 5.  Burnstein.  Protein Production from Acid Whey via
     Fermentation.  EPA, Office of Research and Development.
     Washington, D.C., (1974).

 6.  Caribbean Rum Study;  Effects of Distillery Wastes on the
     Marine Environment.  Office of Research and Development.
     Washington, D.C., April 1979.

 7.  Study of Rum Distillery Waste Treatment and By-Product
     Recovery Technologies.  SCS Engineers, Long Beach,
     California for Industrial Pollution Control Division
     IERL/EPA, (1978).

 8.  Scarberry.  Source Test and Evaluation Report;  Alcohol
     Synthesis Facility for Gasohol Production.  Radian
     Corporation,  McLean, Virginia, 1980.

 9.  EPA, Sampling and Analysis Procedures for Screening of
     Industrial Effluents for Priority Pollutants, April 1979.

10.  Federal Register, Vol. 44, No. 116, June 14, 1979.

11.  Federal Register, Vol. 44, No. 233, December 3, 1979.

12.  Federal Register, Vol. 42, No. 160, August 18, 1977.

13.  Hydrotechnic Corporation.  U.S. EPA Testing of Ethanol
     Plant Wastewater Treatment by Sedimentation and Dual,
     Granular Media, High Rate Filtration.   Prepared for the
     U.S. EPA/EGD, December 1980.

14.  Draft Development Document for Effluent Limitations
     Guidelines and New Source Performance Standards for the
     Beverages Segment of the Miscellaneous Foods and Beverages
     Point Source  Category.  Environmental Science Engineering.
     Internal Draft of the U.S. Environmental Protection Agency.

                                237

-------
15.  Middlebrooks.  Industrial Pollution Control, Vol. It
     Agro-Industries.  John Wiley and Sons, New York, (1979).

16.  Froth Flotation in 1975.  Advance Summary of Mineral
     Industry Surveys, Bureau of Mines, U.S. Department of the
     Interior, Washington, 1976.

17.  Hawley, J. R.  The Use, Characteristics and Toxicity of
     Mine-Mill Reagents in the Province of Ontario.  Ontario
     (Canada) Ministry of the Environment, Ottawa, 1972.

18.  Mining Chemicals Handbook.  Mineral Dressing Notes No. 26,
     American Cyanamid Company, Wayne, New Jersey, 1976.

19.  Seminar for Analytical Methods for Priority Pollutants.
     U.S. Environmental Protection Agency, Office of Water
     Programs, May 23-24, 1978.

20.  Rader, R. D.  Memo to File "Impact of Possible Air
     Standards on VOC Emissions."  September 22, 1981.

21.  United States Environmental Protection Agency, Office of
     Air Quality Planning and Standards.  VOC Fugitive Emission
     in Synthetic Organic Chemicals Manufacturing Industry -
     Background Information for Proposed Standards.  Draft,
     August 1980.

22.  Federal Register, Vol. 45, No. 98, May 19, 1980.

23*  Wastewater Treatment Plant Design.  Water Pollution Control
     Federation.  Washington, D.C., (1977).

24.  Process Design Manual for Upgrading Existing Wastewater
     Treatment Plants.  U.S. EPA, Washington, D.C.,  (1975).

25.  Process Design Techniques for Industrial Waste Treatment.
     Associated Water and Air Resources Engineers, Inc., Enviro
     Press, Nashville, Tennessee,  (1974).

26.  Metcalf and  Eddy, Inc.  Wastewater Engineering.
     McGraw-Hill, New York,  New York,  (1979).

27.  Process  Design Manual for Suspended Solids Removal.   U.S.
     Environmental Protection Agency,  Technology Transfer,
     January  1975.

28.  Benefield,  L. D. and C.1 W. Randall.   Biological  Process
     Design for Wastewater Treatment^.  Prentice-Hall,  Inc.,
     Englewood Cliffs, New Jersey,  (1980).

29.  Weber, W. J.  Physicochemical Processes  for Water  Quality
     Control.  Wiley-Interscience.  New York,  (1972).

                                 238

-------
 30'  Process Design Manual for Land Treatment of Municipal
 31.   Process Design Manual, Sludge Treatment and Disposal.  U S
      Environmental Protection Agency, Municipal Environmental  '
      Research Laboratory, September 1979.

 32.   Conway, R.  A. and R. D.  Ross.  Handbook of Industrial waste
      Disposal.   Van Nostrand  Reinhold Company,  New York, New	
      York,  (1980).

 33.   Gulp,  G.  L.   Handbook of Sludge Processes.  Garland STPM
      Press,  New  York,  New York,  (1979).	

 34•   An Assessment of  the Economic Impacts of Wastewater
      Treatment Requirements on the Ethanol-For-Fuel Industry
      For EPA Office  of  Analysis  and Evaluation.Washington,
      D.C.,  May 1981.

 35.   Burkhead, et.  al.   "Pollution Abatement of a Distillery
      Waste."  Water  and Wastes Eng.  Vol.  6,  No. 5,  (1969).

 36.   Paulette.  "A Pollution  Abatement Program  for  Distilling
      Wastes."  J.  Water Pollution  Control  F^ri. . vol.  42,  No. 7,
      i j.y /u).

 37>   u's* A3-conol  Fuels  Industry Data Base.   Information
      Resources, Inc.  Washington,  D.C., 1985.

 38.   United States Environmental Protection  Agency, Office of
     Air Quality Planning and  Standards.  VOC Emissions from
     Volatile Organic Liguid  Stoarag Tanks - Background	
      Information for Proposed  Standards.Draft EIS, July 1984,
     EPA—450/3—81—033a.

39.  United States Environmental Protection Agency, Office of
     Air Quality Planning and Standards.  Benzene Fugitive
     Emissions—Background Information for~pFomulqated	
     Standards.   EIS, June 1982,  EPA-450/3-80-032b.	
                               239

-------

-------
                           BIBLIOGRAPHY


"Alcohol Plants - Operating & Announced."  List obtained from
the National Gasohol Commission, Educational Services Division,
Lincoln, Nebraska.  August 1980.

Alcohol Week, June 1, 1981.

Alcohol Week, June 15, 1981.

Alcohol Week, July 20, 1981.

Alcohol Week, July 27, 1981.

Behr, Peter (1980).  "$20 Billion Plan on Synfuel Signed,"  The
Washington Post.  July 1, 1980.

Benjes, H. H. (1980).  Handbook of Biological Wastewater
Treatment.  Garland STPM Press, New York, New York.

Bradley, P. R., and J. Y. Oldshire (1972).  The Role of Mixing
in Equalization.  Presented at the 45th Annual Conference of the
Water Pollution Control Federation, Atlanta, Georgia, 1972.

Chemical Engineering, (1979).  "Ethanol-from-biomass plant set
for Louisiana."  Volume 86 (26).

Chemical Engineering, a(1980).  "Chementator."  Volume 87 (2),
page 62 (1980).

Chemical Engineering, b(1980).  August 25.

Chemical Engineering, c(1980).  "The ethanol race:  Waiting for
the Government plan."   Volume 87 (5), pages 80-85.

Chemical Engineering, April 20, 1981.

Chemical Week, "Diamond Shamrock Joins Amstar in an Ethanol
Plan."  Volume 127 (8), page 17, (1980).

"CPI News Briefs."  Chemical Engineering.  Volume 87 (16), page
45 (1980).

Culp, Russell L., et. al., (1978).  Handbook of Advanced
Wastewater Treatment, 2nd Edition.  Van Nonstrand Reinhold
Company, New York, New York.

"Current Ethanol Producers/Buyers."  List obtained from the
National Alcohol Fuels Information Center, Golden, Colorado.
August 1980.
                                240

-------
Davy McKee (1980).  Fuel Alcohol/Report and Analysis of Plant
Conversion Potential to Fuel Alcohol Production.  Davy McKee
Corporation for U.S. National Alcohol Fuels Commission.
Washington, D.C.  September 1980.

Dickr R. I. (1970).  "Role of Activated Sludge Final Settling
Tanks."  Journ. San. Eng. Div., Amer. Soc. Civil Eng., 96, SA2,
423.

Earth Energy  (1980).  Publication of the National Alcohol Fuel
Producers Association, July.

Ethanol:  Farm and Fuel Issues.  Schnittker Associates for U.S.
National Alcohol Fuels Commission.  Washington, D.C., August
1980.

Proceedings of the Environmental Evaluation/ Gasohol Production
and Health Effects Seminar.  EPA Region VII and lERL-Ci.  Kansas
City, Missouri.October 1979.

United States Environmental Protection Agency, Office of Air
Quality Planning and Standards.  VOC Emissions from Volatile
Organic Liquid Storage Tanks - Background  Information for
Proposed Standards.  Draft.  November 1980.

Federal Register, Vol. 43, No. 123, June 26, 1978.

Gasohol U.S.A.  Volume 1 (7).  December 1979.

Gasohol U.S.A.  Volume 2 (1).  January 1980.

Gasohol U.S.A.  Volume 2 (2).  February 198Oe

Gasohol U.S.A.  Volume 2 (3).  March 1980.

Gasohol U.S.A.  Volume 2 (4).  April 1980.

Gasohol U.S.A.  Volume 2 (5).  May  1980.

Gasohol U.S.A.  Volume 2 (6).  June 1980.

Gasohol U.S.A.  -Volume 2 (7).  July 1980.

Gasohol U.S.A.  Volume 3 (3).  March 1981.

Gasohol U.S.A.  Volume 3 (4).  April 1981.

Gasohol U.S.A.  Volume. 3 (5).  May  1981.

Gasohol U.S.A.  Volume 3 (6).  June 1981.

Gasohol U.S.A.  Volume 3  (7).  July 1981.

                                 241

-------
Gasohol U.S.A.  Volume 3  (8).  August 1981.

Recommended Standards for Sewage Works.  Great Lakes - Upper
Mississippi River Board of State Sanitary Engineers.  Health
Education Service, Inc., Albany, New York, (1978K

Gonzalez, et. al.  Biological Effects of Rum Slops in 'the Marine
Environment.  Environmental Research Laboratory, Office of
Research and Development.  Narragansett, Rhode Island.  1979.

Gumerraan, R. C., et. al.  Estimating Water Treatment Costs,
Vols. 1-4.  Prepared by Culp/Wesner/Culp Consulting Engineers
for the U.S. Environmental Protection Agency, Municipal
Environmental Research Laboratory.  August 1979.

Hagler, Bailly and Company.  Alternative Fuels Monitor;  Ethanol
from Biomass.  Energy Process Division EPA, Washington, D.C.,
(1980).

Inside DOE (1980).  "DOE's Alcohol Office Sees 10-Billion
Gallons of Alcohol Output by 1985."   June 27.  Page 7.

Inside DOE.  "TVA Considering Using Waste Heat from Watts Bar to
Power Ethanol Plant.*  McGraw-Hill publication, page 6,
May  2, 1980.

Irvine.  "Sugar-Based Fermentation for Fuel Alcohol."  The First
Interamerican Conference on Renewable Sources of Energy.  New
Orleans, Louisiana, (1979).
   *
Jelen, F. C.  Cost and Optimization Engineering.  McGraw-Hill
Book Company, New York, New York, (1970).

Ladisch.  Cellulosic Residues (Biomass) as a Renewable Source of
Fuels.  Chicago, Illinois, (1980).

Kuby, et. al.  Testing and Evaluation of Two Farm Alcohol
Production Facilities.  Acurex for EPA/IERL-Ci, (1980).

Lyons, Richard L.  "Senate Votes $20 Billion Plan to Produce
Synthetic Fuels."  The Washington Post.  June 20, 1980.

McCombs, Phil.  "Gasohol Proves Popular in Area and Nationwide."
The Washington Post.  June 6, 1980.

Metcalf and Eddy, Inc.  Wastewater Engineering.  McGraw-Hill,
New York, New York, (1972).

Monod, J.  "La technique de Culture Continue - Theorie et
applications."  Ann. Inst. Pasteur (Lille), 79, 390, (1950).
                                242

-------
Murphy, 1 through 11.  "A Set of Notes and Calculatxons for
Sludge Lagoons and Land Application of Sludge."  Prepared for
the U.S. Environmental Protection Agency by Radian Corporation,
McLean, Virginia, July 1980.

Paterson, R. B.  "Computer-Aided Design and Control of an
Activated Sludge Process."  Masters Thesis, University of
Delaware, Department of Chemical Engineering, Newark, Delaware,
(1980).
Paterson, R. B.  "A Set of Notes and Calculations for Costing
Primary and Secondary Wastewater Treatment Systems." Prepared
for the U.S. Environmental Protection Agency by Radian
Corporation, McLean, Virginia, June 1980.

Patterson, W.  L. and R. F. Banker.  Estimating Costs and
Manpower Requirements for Conventional Wastewater Treatment
facilities.  Water Poll. Control Res. Ser. No. 17090DAN10/71,
U.S.  EPA, Washington, D.C.,  (1971).

Peters, M.  S.  and K. D. Timmerhaus.  Plant Design and Economics
for Chemical Engineers.  McGraw-Hill Book Company, New York, New
York, (1968).
Pound,  Charles E., Ronald W.  Crites, Douglas A. Griffes.   Cost
of Wastewater  Treatment by  Land Application.   Prepared for U.S»
EPA,  Office of Water Program Operations, Washington,  D.C.  June
1975.
Radian Corporation,  "Fugitive Emissions  Results for  James  Beam
Distillery,"  December  1980.

Radian Corporation,  "Fugitive Emissions  Results for  White  Flame
Fuels,  Inc.,"  October  1980.

Radian Corporation,  "Generic Air  Sampling Plan for a
Conventional  Alcohol Facility,"  July 1980.

Radian Corporation,  "Generic Sampling Plan for the  Fuel  Alcohol
Point Source  Category,"  July 1980.

 Radian Corporation,  "Site-Specific Sampling Plan,  Archer Daniels
 Midland Plant," June 1980.

 Radian Corporation,  "Site-Specific Sampling Plan,  Georgia
 Pacific," June 1980.

 Radian Corporation,  "Site-Specific Sampling Plan,  Hiram Walker
 Distillery," June 1980.

 Radian Corporation, "Site-Specific Sampling Plan; Jacquins'
 Florida Distillery," June 1980.

                                 243

-------
Radian  Corporation,  "Site-Specific  Sampling  Plan, James  Beam
Distillery," October 1980.

Radian  Corporation,  "Site-Specific  Sampling  Plan, Midwest
Solvents," June  1980.

Radian  Corporation,  "Site-Specific  Sampling  Plan, Milbrew
Incorporated," May 1980.

Radian  Corporation,  "Site-Specific  Sampling  Plan, White  Flame
Fuels,  Inc.," August 1980.

Radian  Corporation.   Frequency of Leak Occurrence for Fittings
in Synthetic Organic  Chemical Plant Process  Units, Final Report.
Austin, Texas, 1980.~~~~	

Radian  Corporation.   The Assessment of Atmospheric Emissions
from Petroleum Refining, Appendix B;  Detailed Results. Austin,
Texas,  1980.                                .        ;—

Radian  Corporation.   Technical Feasibility,  Resource Availabil-
ity, Market Analysis, and Cost Analysis for  the AMFES Fuel
Alcohol Facility in Ames, Iowa.  McLean, Virginia.  1981.

Ramalho, R. S.  Introduction to Wastewater Treatment Processes.
Academic Press, New  York, New York, (1977).:

Rolz, C.  A New Technology to Ferment Sugar  Cane Directly;  The
Ex-Perm Process.  Central American Research  Institute for
Industry.  Guatemala, (1979).

"Sampling and Analysis Procedures for Screening of Industrial
Effluents for Priority Pollutants."  April 1, 1979.   Federal
Register, June 14, 1979 and December 3, 1979.

Schmit,  F. L., et. al.  "The Effect of Tank  Dimensions and
Diffuser Placement on Oxygen Transfer."  J. Water Poll. Control
Fed., £0, 1750, (1978).                  	~~

Schroeder, E. D.  Water and Wastewater Treatment.  McGraw-Hill
Book Company, New York, New York, (1977).

Smith, J. M., et. al.  Upgrading Existing Wastewater Treatment
Plans.  Technology Transfer Design Seminar presented at
Vanderbilt University, September 18, 1972.

Smith, R., et. al.  Design and Simulation of Equalization Basin.
U.S.  Environmental Protection Agency,  Internal Publication,
February 1973.

Sundstrom, D. W. and H. E. Klei.   Wastewater Treatment.
Prentice-Hall,  Inc.,  Englewood Cliffs,  New Jersey, (1979).

                                244

-------
"Synfuel Man, Planning Large Gasohol Plant."  The New York
Times. July 31, 1980.
Synfuels.  McGraw-Hill publication.  March 21, 1980.
Synfuels.  McGraw-Hill publication.  April 4, 1980.
Synfuels.  McGraw-Hill publication.  April 11, 1980.
Synfuels.  McGraw-Hill publication.  April 25, 1980.
Svnfuels.  McGraw-Hill publication.  May 9, 1980.
Svnfuels.  McGraw-Hill publication.  May 16, 1980.
Synfuels.  McGraw-Hill publication.  June 6, 1980.
Svnfuels.  McGraw-Hill publication.  June 13, 1980.
Svnfuels.  McGraw-Hill publication.  June 20, 1980.
Svnfuels.  McGraw-Hill publication.  July 4, 1980.
Svnfuels.  McGraw-Hill publication.  July 11, 1980.
Synfuels.  McGraw-Hill publication.  July 14, 1980.
Synfuels.  McGraw-Hill publication.  August 15, 1980.
Tucker, W. G.  "Recommended Approach to Cost Estimating for
Synfuels PCGDS."  Internal EPA Memo, April 22, 1980.
Tyteca, D., et. al.  "Mathematical Modeling and Economic
Optimization of Wastewater Treatment Plants."  CRC Critical
Reviews in Environmental Control,  December 1977.
U.S.  DOE.  Alcohol Fermentation Plant/Environmental
Characterization Information Report.  U.S. DOE Office of
Environmental Assessments.  June 1981.
U.S.  NAFC.  Fuel Alcohol;  An Energy Alternative  for the  1980's,
Final Report.  U.S.  National Alcohol Fuels Commission.
Washington, D.C.,  (1981).
Viessman, W., Jr., et. al.  Introduction to Hydrology.  Intext
Educational Publishers, New York,  New York,  (1972).
Wallace, A. T.  "Analysis of Equalization Basins."  Journal of
the Sanitary Engineering Division, American Society of Civil
Engineers, SAG, pp.  1161-1171,  (1968).
Wang, et.  al.  Fermentation and Enzyme Technology.  John  Wiley
and Sons.  New York, (1979).
                                245

-------