United States
Environmental Protection
Agency
Office of
Research and Development
Washington D C 20460
April 1979
Water
&EPA
Caribbean
Rum Study
Effects of
Distillery Wastes
on the Marine Environment
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REPORT TO CONGRESS
THE RUM INDUSTRY AND RUM DISTILLERY WASTES
IN PUERTO RICO AND THE VIRGIN ISLANDS:
EFFECTS ON THE MARINE ENVIRONMENT AND
TREATMENT OPTIONS
APRIL 1979
95th Congress Conference Report
No. 95-830
To Accompany H.R. 3199
Prepared by the
Office of Research and Development
U.S. Environmental Protection Agency
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\
? UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
THE ADMINISTRATOR
LETTER OF TRANSMITTAL
Honorable Jennings Randolph
Chairman, Committee on
Environment and Public Works
United States Senate
Washington, D.C. 20510
Dear Mr. Chairman:
The Statement of Managers accompanying the Clean Water
Act of 1977 directed the Environmental Protection Agency to
conduct a study to determine if certain Caribbean rum
distillers might safely dispose of natural wastes untreated
into the marine environment.
I am pleased to submit herewith the report on our
findings.
April 26, 1979 'Douglas M. Costle
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\
w I UNITED STATES£NVIRONMENTAL PROTECTION AGENCY
.
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ATLANTIC OCEAN
N
\
DOM.
REP
JAMAICA
CARIBBEAN SEA
VIRGIN
PUERTO
RICO
Map of the Caribbean
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DISCLAIMER
This report has been reviewed by the U.S. Environmental Protection
Agency and approved for publication. Mention of trade names or commercial
products does not constitute endorsement or recommendation for use.
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ii
FOREWORD
This report is being submitted to the Chairmen of the Senate Committee
on Environment and Public Works and the House Committee on Public Works and
Transportation in compliance with a Congressional request that the U.S.
Environmental Protection Agency study certain wastewater discharges
associated with the Caribbean rum distillers. The study request was
included in the Statement of Managers as part of the Conference Report (No.
95-830, p. 113) accompanying the 1977 amendments to the Clean Water Act.
This report summarizes the Agency's research efforts in response to the
Congressional request. Detailed discussions of the studies are included in
appendices to this report.
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iii
ABSTRACT
The objectives of this study, as stipulated by the Congress, are: (1)
to determine if untreated wastes from rum distilleries in Puerto Rico and
the Virgin Islands are harmful to the receiving waters to which they are
presently discharged; (2) to determine if these wastes can be discharged to
the marine environment for some beneficial purpose, such as aquaculture; and
(3) to examine technologies that might facilitate the use of the nutrients
in these wastes, or might reduce the discharge to the marine environment.
Studies of the receiving waters at three Puerto Rico and Virgin Islands
rum distillery sites demonstrated that the wastes as presently discharged
are not beneficial to organisms in the receiving waters. Organisms studied
in both the field and the laboratory were adversely affected when exposed to
a wide range of concentrations of the wastes. A wastewater analysis showed
the effluent to be very high in biochemical oxygen demand and total solids,
low in pH, low in inorganic nutrients and to contain several compounds
identified by Congress as toxic (priority) pollutants in enacting the 1977
Clean Water Act. Under Section 307(a)(1) of the Act, EPA must control toxic
pollutants through the application of best available technology.
A study of technologies for the treatment and utilization of the wastes
included land disposal, ocean discharge, evaporation, biological treatment,
aquaculture, and process modifications. Land disposal is believed to be a
promising option for two of the distilleries studied, Puerto Rico Distillers
(PRO) and Virgin Islands Rum Industries Ltd. (VIRIL).
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iv
Evaporation of the effluent, resulting in a potentially usable by-product,
CMS (condensed molasses solubles), is a viable option although the CMS
market is uncertain. Biological treatment, in a system comprising an
anaerobic and an aerobic phase, was found technologically feasible to
achieve pollution abatement. Color, however, remains substantially
unaffected. Pilot plants for evaporation at Bacardi's Catano plant and
biological treatment at PRD are now in operation and under study.
Aquaculture was found not to be a promising option. Ocean disposal and
discharge to a POTW were determined to be unacceptable.
An economic study provided a profile of the industry and its relation to
the economies of Puerto Rico and Virgin Islands, and an analysis of the rum
market. The rum industry provides a sizeable and growing share of general
fund revenues in both Puerto Rico (12.7J in 1978) and the U.S. Virgin
Islands (16.MJ in 1978). The degree to which wastewater treatment would
affect the industry as a whole and the individual plants is dependent on
many variables, including cost of treatment methods selected, continuation
of the present tax structure and continuation of sales growth. The study
further indicated that rum sales are presently rising and are projected to
continue to do so for the next decade. The resulting increase in rum
production is expected to cause a corresponding increase in effluent loads.
While the report provides information on several available methods of
rum wastewater treatment, it remains the responsibility of the individual
distillers to select a treatment which they will employ to reduce pollution
to levels acceptable under the Clean Water Act.
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TABLE OF CONTENTS
Disclaimer .
Foreword ii
Abstract ill
List of Illustrations vi
List of Tables vii
Acknowledgment viii
1. Study Background and Design 1
2. Conclusions 5
3. Rum Industry Characteristics 6
Introduction and Summary 6
Industry Structure 7
Process Description 14
Wastewater Characterization 17
Pollutant Reduction Through Process Modification .... 20
U. Effects of Rum Wastewaters on Marine Ecosystems 25
Introduction and Summary 25
Puerto Rico Distillers 27
Bacardi Corporation 39
Virgin Islands Rum Industries Ltd 42
Bioassay Experiments 46
Discussion of Tropical Marine Ecosystems and
Organic Effluents 55
5. Waste Treatment and Utilization Technologies 58
Introduction and Summary 60
Disposal to a POTW 60
Aquaculture 61
Ocean Disposal 62
Disposal by Land Application 64
Evaporation, with CMS By-product 68
Biological Treatment 72
6. Economic Assessment 76
Introduction and Summary 76
Relationship of the Rum Industry to the Economies
of Puerto Rico and the Virgin Islands 77
Economic Implications of Wastewater Treatment 79
References 86
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vi
List of Illustrations Page
Figure
Map of Caribbean
1 Graph, rum production, 1960-1978 8
2 Graph, rum as % of total liquor consumption 9
3 Map, showing locations of distilleries 10
4 Flow diagram of a typical distillery 15
5 Map of Arecibo, PRO site 30
6 Photo of Arecibo, PRD Site 31
7 Close-up of PRD discharge pipe 32
8 Photo of stained surf at Arecibo, west of discharge
point 32
9 Photo of Bacardi plant at Catano, aerial 44
10 Map of Catano area, Bacardi plant site 45
11 Photo of Bacardi outfall structure, Ensenada
de Boca Vieja 45
12 Map of St. Croix, V.I., VIRIL site 47
13 Photo of outfall and plume from VIRIL discharge
site 48
14 Map, location of tidepools studied at Arecibo 51
15 Graph, survival of transplanted Echinometra lucunter
in tidepools at Arecibo with and without effluent
discharge 55
16 Graph, bioassay of mosto in seawater: survival of
Echinometra lucunter 57
17 Graph, bioassay of mosto in seawater: survival of
Chiton squamosus 57
18 Graph, bioassay of mosto in seawater: effect
on righting behavior of Echinometra luounter 58
19 Graph, bioassay of mosto in seawater: survival of
Brachidontes exustus 58
20 Graph, bioassay of mosto in seawater: survival of
Callinectes sapidus 59
21 Graph, bioassay of mosto in seawater: effect on
byssal thread production by the mussel Brachidontes
exustus 60
22 Photo of Serralles plant surrounded by cane fields . . 72
23 Photo of Anamet pilot plant in operation at PRD .... 81
24 Diagram of Anamet system 81
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Vll
List of Tables Page
Table 1 Estimated operating levels of rum distilleries
and other statistical information 13
2 Priority pollutants in mosto and combined
effluent 19
3 Mosto from three distillers: conventional
parameters 21
4 Intertidal samples taken at the discharge site at
Arecibo before and after resumption of mosto
discharge 32
5 Intertidal samples at an upstream control station
at Arecibo before and after resumption of mosto
discharge 33
6 Tidepool fish species observed on selected dates
at Arecibo 34
7 Biochemical oxygen demand at selected distances from
effluent outfall in coastal waters at Arecibo on
various dates 37
8 Chemical oxygen demand at selected distances from
effluent outfall in coastal waters at Arecibo on
various dates 38
9 Survival of transplanted Echinometra lucunter in
tidepools before resumption of effluent
discharge 48
10 Effects of effluent of dissolved oxygen levels in
a tidepool at the PRD, site, Arecibo 48
11 Largest possible capital investment for waste treatment
with model plants remaining viable (no closure) ... 84
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Vlll
ACKNOWLEDGMENTS
The cooperation of a number of individuals and organizations in Puerto
Rico and the Virgin Islands is gratefully acknowledged. First, the
assistance of Mr. Weems Clevenger of the EPA San Juan office was invaluable
in many aspects of the project. Within the Puerto Rican government, special
thanks are extended to Mr. Julio Cesar, Secretary of the Treasury, Mr.
Bertram Finn, Director, Office of Economic Research, Economic Development
Administration; and Mr. J.M. Mitchelhill, Assistant to the Executive
Director, Sugar Corporation of Puerto Rico. Similarly, in the Virgin
Islands government, thanks are due Mr. Henry Millin, Lt. Governor; Mr. John
Tinsley, Chief Economist, Department of Commerce; Mr. William Quetel,
Assistant Director, Industrial Development; Mr. Claude Christain, Department
of Finance; and Mr. William Blum, Department of Commerce.
Considerable help also was given by rum industry personnel. Within the
Bacardi Corporation, thanks are due Mr. Alfred O'Hara, President, and Mr.
Richard Reiss, Vice-President and General Manager. Dr. George Dorion,
Director of Advanced Projects, was particularly helpful in arranging for
visits to the Bacardi San Juan Plant and in providing information and
technical data. Likewise, Mr. Felix Serralles, Jr., arranged for a most
instructive tour of the Destilleria Serralles facilities for EPA personnel.
Also helpful were Dr. Herminio Brau, President of Puerto Rico Distillers,
Inc. and Messrs. Cedric Nelthropp and Milton Seasonwein of Virgin Islands
Rum Industries, Ltd. Mr. Carlos Yordan, Executive Secretary of the Puerto
Rico Rum Producers Association, Inc., also has been most helpful.
Photographs in this report were taken by E. Zell Steever.
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SECTION 1
STUDY BACKGROUND AND DESIGN
Section 304(b)(1)(A) of the Federal Water Pollution Control Act
Amendments of 1972, (P.L. 92-500) required the U.S. Environmental Protection
Agency (EPA) to establish effluent limitations guidelines for categories of
industrial point sources. Guidelines have not been promulgated for
distillers of rum in Puerto Rico and the Virgin Islands because sufficient
information specific to Caribbean cane molasses rum production was not
available to formulate a guidelines subcategory. In the absence of
guidelines, National Pollutant Discharge Elimination System (NPDES) permits
were issued to Caribbean distillers by EPA in 1974 and 1975 based upon "best
engineering judgment" under authority of section 402(a)(1) of the FWPCA.
One distiller, Bacardi Corporation, accepted its NPDES permit; the other
distillers, Puerto Rico Distillers, Inc. (PRO) and Schenley Industries,
{operator of Virgin Islands Rum Industries Ltd. (VIRIL)l challenged the
terms of their permits and requested adjudicatory hearings.
A consolidated hearing was convened in July 1977 and adjourned after two
weeks of testimony. Although the hearing has not been reconvened, EPA and
the rum distillers have continued negotiations toward a resolution of the
controversy over effluent limitations. As part of the negotiation process,
EPA established a Technical Committee in August 1978, composed of technical
experts from EPA and the rum industry, for the purpose of reaching a
consensus on the issue of available alternatives for the treatment of rum
wastes.
The issue of treatment requirements for the Caribbean rum industry also
was raised before the House Committee on Public Works and Transportation as
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part of deliberations on 1977 amendments to the Federal Water Pollution
Control Act. Consequently, the Statement of Managers in the Conference
Report accompanying these amendments, subsequently adopted as the Clean
Water Act of 1977 (P.L. 95-217), contained the following provision:
It has been stated that some Virgin Islands and Puerto Rico rum
distillers might safely dispose of certain natural wastes
untreated into the marine environment. In response to these
statements, the conferees direct the Administrator to conduct a
study, to be completed by January 1979, to ascertain if there is
merit in this argument and if disposal can be environmentally
acceptable or even possibly beneficial. In this study the
Administrator should specifically examine geographical,
hydrological and biological characteristics of marine waters
receiving such wastes to determine if the discharge can be
environmentally acceptable either for the purpose of aquaculture or
some other purpose. In addition, the study should examine
technologies which might be used in these industries to facilitate
the utilization of the valuable nutrients in thes|swastes or the
reduction in discharge to the marine environment.
To comply with this Congressional request, EPA organized a research
effort in which Agency scientists and non-governmental technical and
scientific consultants participated. The research tasks were as follows:
•It is assumed that the term "organic wastes" was intended here. The term
"natural wastes" is generally understood to designate substances that enter
the environment as a result of "natural" processes, or those that are not
the result of human industry or commerce. The distillery discharge is an
industrial effluent composed mainly of organic by-products of fermentation
and distillation.
"House Conference Report No. 95-830 accompanying H.R. 3199, 95th Congress,
1st Session, p. 113, reprinted in A Legislative History of The Clean Water
Act of 1977, Vol. 3, p. 297, Senate Committee on Environment and Public
Work¥7 35TE Congress, 2d Session (1978).
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1. A study of the geographical, biological and hydrological
characteristics of the marine environment at two distilleries in Puerto Rico
and one distillery in the Virgin Islands, and an assessment of the effects
of the effluent discharge on the marine environment (Section 4 of this
Report). The study was conducted by:
The Marine Ecology Division at the Center for Energy and
Environment Research (CEER), affiliated with the University of
Puerto Rico and the U.S. Energy Research and Development Agency.
CEER laboratory at Mayaguez, P. R. Dr. Juan G. Gonzalez, Project
Leader, under an interagency agreement between EPA and the U.S.
Department of Energy. #IAG-78-D-X0225
Report: "Biological Effects of Rum Slops in the Marine Environment"
(1979)
Short title: Puerto Hico Report
The Virgin Islands Environmental Research Service at the
College of the Virgin Islands, St. Thomas and St. Johns. Dr.
Michael J. Canoy, Project Leader, under an EPA grant. #806110
Report: "Environmental Effects and Acceptability of Effluents from Rum
Distilleries" (1979)
Short Title: Virgin Islands Report
2. An analysis of rum slops (mosto in Spanish), other waste stream
components, and total combined waste stream at each of three distilleries
(Section 3 of this report). This analysis was performed by:
EPA Region IV, Surveillance and Analysis Division (SAD), Athens,
GA. Mr. Steve Hall, Project Leader.
Report: "Rum Wastewater Characterization Study, Puerto Rico and Virgin
Islands, July 17-22, 197B" (1979)
Short Title: SAD Wastewater Study
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3. An evaluation of the various waste treatment, by-product recovery
and waste utilization alternatives (Section 5 of this Report). This
evaluation was conducted by:
Stearns, Conrad and Schmidt, Consulting Engineers, Inc.
(SCS), Long Beach, CA., Mr. Kenneth LaConde, Principal Investigator,
on contract to EPA.
Report: "Study of Rum Distillery Waste Treatment and By-product
Recovery Technologies" (1979)
Short Title: SCS Technology Study
4. A study of the rum market structure and, through economic modelling,
the financial impact of effluent controls (Section 6 of this Report). This
study was conducted by:
Development Planning and Research Associates (DPRA),
Manhattan, KS. Mr. Richard Seltzer, Principal Investigator, on
contract to EPA.
Report: "Economic Impact of Effluent Regulations on the Rum Industry
(Puerto Rico and Virgin Islands)" (1979)
Short title: DPRA Economic Study
The research efforts were coordinated by the EPA Office of Research and
Development, Environmental Research Laboratory, Narragansett, R.I., E. Zell
Steever, Project Coordinator; and the EPA Office of Water Enforcement,
Washington, D.C., Harry Thron, Project Coordinator.
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SECTION 2
CONCLUSIONS
This study was designed to address the questions posed by the
Congress. EPA believes this report adequately responds to those
questions.
The study was not intended to be a definitive exploration of all
issues relating to effluent discharges by the rum distilling industry.
The investigations, nonetheless, provided a great deal of information on
the nature of rum wastewaters, effects of these wastewaters on the marine
environment, and treatment, reuse and disposal alternatives. This
information has led to the following conclusions:
1. Chemical analyses of rum distillery effluents confirmed the
presence of high concentrations of organic materials and the
presence of heavy metals and some toxic (priority) pollutants.
2. Direct discharge of rum distillery effluents as presently
practiced is harmful to the marine environment.
3. Aquaculture/mariculture is not a feasible alternative for rum
waste treatment or utilization at the present time.
4. Addition of mosto to the "nutrient-poor" marine ecosystems of the
Caribbean considered in this study does not improve water quality.
5. Technically feasible alternatives are available for waste
treatment or disposal of rum distillery effluents.
6. There are technically feasible effluent treatment or disposal
alternatives that are economically affordable.
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SECTION 3
RUM INDUSTRY CHARACTERISTICS
INTRODUCTION
This section describes the present structure of the rum industry, the
process of rum production, the composition of the three distilleries'
wastewater streams and their major components, and some possible
modifications in the rum production process that can result in pollution
reduction.
Summary:
The U.S. Caribbean rum industry has grown markedly during the past two
decades, although the number of distillers has declined to a total of five,
operating six plants. The growth in demand for rum, and hence of
production, continues today, as rum's share in the total U.S. liquor market
continues to expand.
Rum manufacture is a process of fermentation and several distillation
steps, in which wastes are generated from a number of sources. The mosto
stream from the main still, or alcohol stripping column, contains nearly all
(over 95$) of the pollution load.
A wastewater analysis revealed the presence in the effluent of toxic
(priority) pollutants, which appear to be a less serious problem than the
very high levels of organic compounds and attendant high biochemical oxygen
demand (BOD ) and chemical oxygen demand (COD).
Certain modifications in the rum production process can reduce pollutant
levels in the effluent.
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Outline:
Industry Structure
Process Description
Wastewater Characterization
Priority Pollutants
Conventional Pollutants
Pollutant Reduction Through Process Modifications
INDUSTRY STRUCTURE1
During the past two decades the U.S. Caribbean rum industry has
experienced significant expansion and change (Fig. 1). In the early 1960s,
rum production moved from a period of stability to one of appreciable
growth. Competition among the distilleries was strong, and the more
efficient ones increased their production markedly. By the end of the
decade, the industry had become dominated by a small number of comparatively
large distilleries. The demand for rum continued to grow in the 1970s,
along with a steady increase in rum's share in the U.S. liquor market (Fig.
2).
The Puerto Rico and U.S. Virgin Islands rum industry presently consists
of five distillers. These distillers, from largest to smallest in terms of
annual rum production are listed below and are located on the accompanying
map (Fig. 3):
Bacardi Corporation (2 plants)
Puerto Rico Distilleries, Inc. (PRO)
Destilleria Serralles, Inc.
Virgin Islands Rum Industries, Ltd.
(VIRIL)
Brugal and Company
San Juan (Catano), Puerto Rico
Arecibo, Puerto Rico
Ponce (Mercedita), Puerto Rico
Fredericksted, St. Croix,
U.S. Virgin Islands
Fredericksted, St. Croix,
U.S. Virgin Islands.
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28
24
CO
O
20
U- ,e
O I6
O
DC
a.
12
O
-I
d 8
PUERTO RICO
RUM PRODUCTION
VIRGIN ISLANDS
RUM PRODUCTION
I i i
t I I I I I
I960 62 64 66 68 70
YEAR
72 74 76
Figure 1. Hum Production, 1960-1978
* A proof gallon of rum is defined as one gallon of rum at 100 proof (50?
alcohol). Based on the commonly sold fifth bottle of rum at 80 proof, 6.25
bottles of rum equal 1 proof gallon.
Source: DPRA Economic Study
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RUM AS % OF U.S. LIQUOR CONSUMPTION
IU
UJ
1 8
o
_J
? 6
0
1-
u_
0 4
UJ
O r>
a:
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10
(PRO)
ATLANTIC OCEAN
(BACARDI, OLD SAN JUAN)
X. /(BACARDI)
ARECIBO
PUERTO RICO
A
N
SAINT
THOMAS
VIRGIN ISLANDS
(SERRALLES)
CARIBBEAN SEA
(BRUGAL)
(VIRIL)
MILES
0 30
i il
SAINT CROIX
DISTILLERY SITES
0 35
KILOMETERS
Figure 3. Map, showing locations of distilleries in the U.S. Caribbean.
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11
Bacardi operates two separate distilleries. The main distillery in
Catano, P.R., has been operating since 194*1. The newly acquired (July 31,
1978) Old San Juan Distillery was previously owned by Schenley Industries.
Both facilities discharge their untreated wastewaters into the Ensenada de
Boca Vieja estuary.
PM) has operated its distillery in Arecibo since the late 1800s. At
present untreated wastewater is discharged directly to the beach and thence
to the Atlantic Ocean.
Destilleria Serralles is adjacent to the Serralles family's Mercedita
sugar cane fields near Ponce, P.R. Since 1935, Serralles has disposed of
its wastewater by applying it, diluted with fresh irrigation water, to the
cane fields and other crops. A small volume of the wastewater entered the
nearby Inabon River until 1977 when the distillery upgraded its wastewater
control program by installing a closed loop "no discharge" land application
system. Presently, Serralles discharges no wastewater into any body of
2
water and thus requires no NPDES permit.
The VIRIL distillery on St. Croix, V.I. discharges its wastewater to a
former regional sewer duct which conveys the untreated plant effluent to the
Caribbean Sea and discharges it about 600 m offshore in about 6 m of water.
The smallest rum distillery, Brugal, is also on St. Croix, and trucks
its wastewater to the publicly owned treatment works (POTW) plant where it
is discharged untreated with the treated effluent from the POTW to the
Caribbean Sea via an outfall pipe 2700 m long.
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12
In addition to these six distilleries, at least four plants rectify,
blend, bottle, and/or sell rum. These non-distilling operations purchase
rum from the distilleries.
Of the five distilling firms in Puerto Rico and the Virgin Islands,
three are owned by publicly traded corporations and two are privately
owned. Serralles is owned by the Serralles family and Brugal by the Brugal
family. (Brugal operates two other distilleries in Santo Domingo.)
PRD is owned by the Seagram Company, the world's largest distiller,
which operates plants in the United States, Canada, and other countries.
VIRIL is owned by Schenley Industries which, in turn, is owned by
Rapid-American, a diversified corporation with interests in retail
merchandising, importation and sale of alcoholic beverages as well as the
manufacture and sale of men's apparel and other soft goods.
Bacardi Corporation is a publicly owned company traded on the
over-the-counter market. The company distills, rectifies, and bottles rum
in Puerto Rico. Its wholly-owned subsidiary, Castleton Beverage
Corporation, bottles rum in Jacksonville, Florida.
Firms in the rum industry typically are not diversified. While the
owning families or parent corporations may be involved in nonrelated
industries, most firms in the rum industry are involved only in the
manufacture and sale of alcohol and alcoholic beverages.
Some distilleries currently operate at less than maximum capacity
(mostly by operating on only a limited number of days per year) while others
operate at near capacity. The estimated annual production figures (and
other statistics) for each distiller are presented in Table 1.
•Capacity is estimated since exact data were not available from the
distillers.
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13
TABLE 1: Estimated operating levels and other statistics for Puerto Rico and Virgin Islands rum
distilleries, 1977-1978
Estimated
Run Production
Million Proof
Company 8t Location Gals/Year
Bacardi, P.R. 18. U
Bacardi, P.R.
(former Schenley)
Puerto Rico Distillers,
P.R. t.8
Distillerla Serralles,
P.R. 3.8
VIRH, (Sohenley), V.I. 3.1*
Brugal & Co., V.I. 0.2
Proof
Gals/ Day
60, 000
25,000
15,000
12,500
800
Estimated
Operating
Days/Year
300
200-250
250
200
Estimated
Plant Site
Land (Acres)
125
16
4,000*
25
Estimated Gallons
Volume of
Hosto/day
300,000
60,000
200,000
150,000
65,000
5,000
•Includes Serralles sugar cane fields surrounding distillery
Source: Information supplied to U.S. EPA in verbal communications from rum industry personnel. See also
Puerto Rican Rum Producers' Association 1977-78 Report and Alcohol Control Board data, Government of the
Virgin Islands, 1977-78.
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14
PROCESS DESCRIPTION3
Rum is made by fermenting a dilute solution of cane molasses with yeast
for one to two days and then distilling the fermentation "beer" to recover
ethyl alcohol. Molasses, also known as "Blackstrap" cane molasses, a
by-product of the cane sugar industry, is purchased by the distillers and
stored in large holding tanks prior to use. The molasses is then pumped to
a tank or vat where phosphorus and nitrogen are added to satisfy the
nutritional requirements of yeast in fermentation. To eliminate the
possibility of undesirable bacteria growth, the pH is adjusted to between 4
and 5 through the addition of sulfuric acid and the molasses is diluted with
water to about 22° Brix» (range 18° to 24°), a sugar concentration of
about 12$.
The fermentation process begins as the yeast first converts the sucrose
into equal parts of glucose and fructose. These in turn are converted into
alcohol and carbon dioxide. The fermentation process yields a waste stream
primarily made up of yeast residues, sometimes referred to as fermenter
sludge. The resulting fermentation product, known as "beer" or mash (&% to
12$ alcohol), is then fed continuously through a multi-column distillation
process to separate the ethyl alcohol from the spent molasses and
fermentation by-products. A typical distillery arrangement is shown in
Figure 4.
The first distillation column—the alcohol stripping column—is operated
continuously for as long as six months, until it must be cleansed of the
*A measurement for sugar solutions that expresses, on the basis of specific
gravity, the total solids content.
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15
FLOW DIAGRAM
A TYPICAL RUM DISTILLERY
MOLASSES,
ADDITIVES.
WATER
YEAST
FERMENTATION
TANK
ALCOHOL STRIPPING ALDEHYDE
COLUMN COLUMN
CONDENSOR
WASTE
RECTIFYING
COLUMN
PRODUCT
95% ETHYL ALCOHOL
(ETOH) TO OAK BARRELS
FOR AGING 1-3 YEARS
j 'IUWKU.IUMU..|4*HP3W*««W^>I
HEAVY
SS*:<*^ ~* KS&- /-I
FUSEL OILS!
««IBife^^-'> •>. "-^IBilKMl
Figure 4.
Source: SAD Wastewater Study
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16
encrustations or "scale" that, in time, clog the passages (or bubble caps)
between chambers in the distilling column. The heat applied at the bottom
of the column causes the ethyl alcohol (ETOH) and other volatile products to
rise as vapor into the condenser above the column, where on cooling they
liquefy and are collected for further refining. This stripping process
yields the major waste component in the rum production process, the "slops"
or mosto.
The second still, ordinarily, is the aldehyde column. Here ketones,
aldehydes, low boiling esters—the more volatile or lower boiling fractions
in the alcohol, called "heads"—are collected and removed. These heads may
be redistilled to recover whatever alcohol remains. Since the heads are
combustible, they may be recovered and used as boiler fuel. (This is
presently the case with VIRIL and PRO).
The product is drawn off the bottom of the aldehyde column and sent on
to the third still, or rectifying column, where the fusel oils and amyl
alcohols are removed. These waste products may become part of the waste
stream, or may be recovered and used as solvents or fuels. Other
distillation columns may be employed to further refine the product.
After the fermentation/distillation/rectifying process—which varies
from one distillery to another—the final product is aged in oak casks for
one to three years. Finally, it is filtered, diluted, blended, bottled and
sold.
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17
WASTEWATER CHARACTERIZATION14
In rum production, waste streams are generated from a number of
sources: the fermentation tank (yeast heal), alcohol stripping column
(slops or mosto), aldehyde column (heads), rectifying column (fusel oils)
and other ancillary processes, such as cleaning, cooling and boiler
blow-down (see Fig. 4, above). A general characterization of these waste
streams was undertaken to aid in the assessment of the various possible
waste treatment technologies and to better understand the impact of the
effluent on the marine environment. Toxic (priority) pollutants and
conventional pollutants were considered in this characterization.
The Region IV EPA Surveillance and Analysis Division (SAD) conducted the
surveys at Bacardi, PRD and VIRIL, taking samples at several points of waste
generation at each plant on five consecutive days. Composite samples were
taken of the undiluted slops or mosto stream and of the "combined effluent"
where possible. Single grab samples were collected from each facility's
raw process water, fermentation tank, aldehyde column, and rectifying
column. Flow rates of the wastewater streams also were determined.
'Because the VIRIL total effluent stream contains only a very small amount
(5% or less) of material other than the slops or mosto, separate analyses
were not performed on the VIRIL mosto stream and final effluent stream. The
PRD final effluent contained a significant volume of cooling water. The
Bacardi waste streams were not fully combined at the outfall; refer to the
SAD Wastewater Study, figure 2, and the section entitled "Sampling Station
Locations and Samples Collected," and the entire document for further
information on the wastewater analyses.
-------
18
Samples requiring immediate analysis were analyzed at the laboratory of
the University of Puerto Rico in San Juan. All other chemical analyses,
excluding those for toxic organic (priority) pollutants, were performed by
the EPA, SAD laboratory in Athens, Georgia. The organic compounds were
analyzed at West Coast Technical Services, Inc., laboratories in Cerritos,
California.
Toxic (Priority) Pollutants
Several compounds included in the list of toxic materials (priority
pollutants) identified by Congress in the Clean Water Act were detected in
wastewaters at each facility. These toxic (priority) pollutants were found
in the raw process water supply, mosto stream, fusel oil, aldehyde heads and
combined effluent from each facility. The toxic (priority) pollutants found
in the mosto and combined effluent streams are shown in Table 2. The
effects of these substances on the marine environment were not directly
addressed in this study.
Conventional Pollutants
Of all the waste stream sources in rum production, the mosto stream is
by far the most important; it is estimated to constitute 65% of the volume
-------
19
TABLE 2:
Toxic (priority) pollutants in mosto and combined effluent
ug/1 = part/billion
BACARDI
PRO
VIRIL
Undiluted
Mosto
Combined1
Effluent
Undiluted
Mosto
Combined*
Effluent
Combined*
Effluent
ORGANIC"
Phenol
Bis (2 ethylhexyl) ph thai ate
r-BHC-Garane
1,1-di chloroethylene
Toluene
Carbon tetraohloride
1,1,1 trjchloroethene
Naphthalene
Benzene
Beptachlor epoxide
Dibenzo (a,h) anthracene
INORGANIC
387 i 59
10
68
10
0.317
10
210
252
29
41
10
0.07&0.36"»
10
96
10
10
0.316«««
193
110
13
140
520
Sb
As
Be
Cd
Cr
Cu
Pb
Hg
Hi
Se
A«
Tl
Zn
Phenols (total)""
Cyanide
12
78
190
3850
1110
7.5
600
60
2900
1780
3
16
85
269
7200
1350
4.6
675
60
2560
1080
4
16
62
470
5220
940
4
830
51
1170
925
14
20
10
10
125
450
103
4
53
10
10
7
78
77
7
14
83
264
4080
1250
2.2
1040
58
4053
1025
15
Source: SAO Waatewater Study
* See footnote on p. 17.
** The analysis showed large amounts of methylene chloride in many of the samples. These readings, however, are
thought to reflect laboratory use of methylene chloride in performing the analyses rather than a feature of the rum
effluent and thus are omitted from the table.
»•• Hot confirmed by GC/MS.
"••By the 4 AAP Procedure (Standard Methods).
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20
5
of the rum effluent and to contain over 95% of the pollutants. The exact
chemical composition of the organic fraction of mosto is uncertain, but it
is basically a mixture of sugar (estimated to be 5% to 8% by weight),
organic acids, amino acids, proteins, polysaccharides, and inorganic salt
complexes. Analysis by gas chromotography/mass spectrometry (GC/MS)
revealed numerous oxygenated compounds, none of which is known to be highly
toxic.
A comparison of the important characteristics of mosto for the three
distillers under study is summarized in Table 3- Although production
processes are quite similar, wastewater composition was found to vary
somewhat in composition from distillery to distillery and probably also from
batch to batch. Quality of molasses and process differences, including
controls on Brix and distillation time, fermentation time, additives used,
and heating and cooling methods account for some of this variation.
Beyond these relatively minor differences, the analyses reveal very high
levels of organic material in the form of carbon compounds and total solids
in the mosto streams of all three distilleries. These factors contribute 'to
the high BOD /COD, which results in oxygen depletion in the receiving
waters. This characteristic appears to be the major problem associated with
rum effluents, and probably accounts for much of the damage to marine
organisms observed in biological studies discussed in Section U. The
amounts of nitrogen, phosphorus and other inorganic compounds are comparable
to levels found in domestic wastes.
POLLUTANT REDUCTION THROUGH PROCESS MODIFICATION6
A number of production process modifications are available to rum
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21
TABLE 3: Mosto stream from three distillers: selected conventional pollutants: 5 day averages in mg/1.
Bacardi
PRO
TIB1L
BOD5
32,000
27,000
36,000
ODD
101,000
75,000
112,000
Total
Organic
Carbon
34,300
27,300
J»2,260
Organic
Nitrogen
859.0
550.0
952.0
Ammonia
Hitrogen
16.3
6.9
9.0
Phosphorous
138
118
119
Total
Suspended
Solids
6, « 00
4,700
9,700
Total
Solids
95,000
76,00
116,000
pH
1.8
4.7
5.1
Source: SAD Wastewater Study
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22
distillers that could result in reductions of certain pollutants, improved
plant efficiency, water and energy conservation, recycling of waste
products, and recovery of other fermentation by-products. Among the more
significant of such options are:
1. Pretreatment of molasses prior to fermentation;
2. Removal and recovery of yeast from fermenter beer;
3. Removal of fermenter bottoms;
U. Recovery of fusel oil and "heads" as fuel supplements or other
useful by-products;
5. Indirect heating of alcohol stripping column.
Pretreatment of Molasses
Molasses pretreatment is a well known technology in the distilling
industry. The process clarifies and pasteurizes the raw molasses, removing
gums, sludges, salts and unwanted microorganisms—materials that tend to
inhibit yeast fermentation and form the "fermenter bottoms" that must be
removed or become a part of the waste stream.
Pretreatment is achieved by diluting the molasses, acidifying it with
sulfuric acid, and raising the temperature almost to the boiling point.
Separation is generally carried out in settling tanks or by use of an
ejecting-type molasses clarifier.
Pretreatment has important benefits. Clarification and pasteurization
of the molasses yields a cleaner "beer" and alcohol; consequently, the
alcohol stripping column in the distillation process requires fewer
stoppages for descaling, and reduction in the build-up of sludges in this
column permits longer periods of operation. Pretreatment does, however,
require additional energy and capital, and there is reportedly some loss of
fermentable sugars involved in the process.
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23
A partial pretreatment of molasses can be accomplished simply by
dilution and then centrifugation. Without heating or acidification,
however, neither pasteurization of the molasses nor precipitation of calcium
salts is achieved.
Yeast Recovery
Yeast can be eliminated from the fermenter beer before distillation by
centrifugation. The centrifuged yeast may then be recycled for reuse in the
fermenters, sold for an animal feedstuff (with or without drying), or land
disposed.
Another version of yeast recovery known as the Melle-Boinet technique
shortens fermentation time to 14 hours (from 24 to 72 hours), with up to 5%
increase in alcohol yield. With this recycling technique, a high yeast
concentration is maintained in the fermenter and cell reproduction is
reduced, thus allowing sugars previously used for yeast growth to be
converted into alcohol. With proper care, the yeast can be recycled up to
7
30 times before an appreciable loss in activity occurs. This method can
only be used where molasses has first been pasteurized and pretreated to
remove components which inhibit the yeast.
Removal of Fermenter Bottoms
Fermenter bottoms are the unfermentable solids and dead yeast
cells—"heal of yeast"—which settle to the bottom of a fermentation tank
and form sludge. When fermentation ceases, the liquid or "beer" containing
the live yeast cells, alcohol and spent molasses is drained off for possible
yeast recovery and distillation. Sludge must be washed out of the tanks
before the next fermentation cycle.
-------
Eliminating suspended inorganic and organic materials (other than the
live yeast) which could become part of the rum wastewater discharge can be
accomplished by the removal of fermenter bottoms as well as by molasses
pretreatment. It has been the practice at many distilleries to discharge
this sludge to the local sewer drain. An alternative is removal by using a
sludge pump to a holding tank and then land disposal. The advantages of
removal of fermenter bottoms over molasses pretreatment are reported to be
lower capital and operating (energy) costs and higher alcohol yields. Even
higher yields, however, can probably be realized when yeast recycling is
practiced along with molasses pretreatment.
Recovery of Fusel Oils and "Heads"
Fusel oils and aldehyde heads may be removed from the distilling columns
to a storage tank and then burned in the plant's boiler system.
Both VIRIL and PRD already recover fusel oil and heads and burn them as
fuel on a continuous basis. Bacardi expects to install a recovery system by
the end of this year. Fusel oils may be recovered and marketed as solvents.
Indirect Heating of Alcohol Stripping Column
When heat is supplied internally by direct steam injection into the
bottom of the column, condensed steam (water) from this heating method will
add 15$ to 20$ to the mosto volume. This increased volume will result in
higher design flow values and, consequently, higher treatment costs,
particularly for evaporation. External indirect heating through heat
exchangers avoids adding this condensate to the waste stream. Indirect
heating systems are in operation currently at the VIRIL plant.
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25
SECTION 4
EFFECTS OF RUM WASTEWATERS
ON MARINE ECOSYSTEMS
INTRODUCTION
The rum distillers of Puerto Rico and the U.S. Virgin Islands have been
discharging untreated wastes directly into the nearshore marine environment
for many years. The effluent is a spent molasses-like mixture with a high
organic content, high BOD,-, unfermented sugars, fermentation by-products,
organic acids, and various inorganic materials (Section 3). At each site
the effluent forms a plume that follows the prevailing current and is
clearly visible for one to six kilometers downstream from the point of
outfall.
Studies were conducted in Puerto Rico and in the Virgin Islands
(beginning in May 1978 and substantially completed in September 1978) on the
effects of this effluent on the marine environment. In each case, one
distillery site was selected, at which the near field effect of the rum
distillery discharge was the focus of the research. In Puerto Rico, the
main criterion for selection was the relative absence of other sources of
pollution near the site; thus the PRO plant site at Arecibo was indicated.
Abbreviated field studies also were carried out at the Bacardi outfall
site. In the Virgin Islands, the site of the VIRIL plant, the Islands' only
sizeable distillery, was studied.
The research teams in Puerto Rico and the Virgin Islands undertook field
studies to determine the design for a series of field and laboratory
bioassay experiments through which the effects of the effluent on the marine
-------
26
community could be assessed. The time frame did not allow for prior
gathering and analysis of baseline information or for evaluating seasonal
variations. Study designs and methods are detailed in the separate
, 8,9
reports. '
Summary:
Observations at the three distillery sites indicated that the rum
effluents as presently discharged are harmful to the marine environment.
Certain indigenous organisms were absent or rare in the presence of the
discharge. These observations were confirmed by field and laboratory
bioassays, in which two selected test organisms, the sea urchin Echinometra
lucunter and the "coat-of-mail" shellfish Chiton squamosus evidenced
mortality and altered behavior at the lowest mosto concentration tested,
.01$, or a dilution of 1:10,000. Two other organisms, the mussel
Brachidontes exustus and the crab Callinectes sapidus, were more resistant
to the mosto in laboratory tests, and survived in dilutions of 1:200. In
field bioassays, however, most of the crabs confined in the effluent plume
died, probably as a result of oxygen depletion in the water column and the
anoxic (without oxygen) condition of bottom sediments, related to the high
BOD5/COD of the effluent.
Outline:
Puerto Rico Distillers: Arecibo and the Atlantic Ocean
Site Description
Field Studies
Bacardi: Catano and the Ensenada de Boca Vieja
Site Description
VIRIL: St. Croix and the Caribbean Sea
Site Description
Field Studies
Bioassay Experiments
Field Bioassays
Laboratory Bioassays
Discussion of Tropical Marine Ecosystems and Organic Effluents
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27
PUERTO RICO DISTILLERS: ARECIBO AND THE ATLANTIC OCEAN10
Site Description
The PRD distillery at Arecibo, (Fig. 5), unlike the Bacardi plant at
Catano, is relatively free of other sources of pollution. (A raw sewage
outfall and small fresh water influents east and upcurrent of the PRD plant
are exceptions). Control or "reference" areas were established as follows:
(1) about six kilometers east of PRD at Islote, a previously well-studied
area where conditions are similar in most respects; and (2) downstream
beyond the influence of the plume.
The distillery is situated on an eroded cliff (Fig. 6) overlooking a
*
rocky sand beach. PRD discharges about 200,000 gallons of mosto a day
during its 200 to 250 days of annual operation. At the beginning of the
study period, May 9, 1978, no mosto was being discharged, nor had any been
discharged for about 6 weeks. Mosto discharge commenced on about May 23,
and was intermittent through June 6; from then until July 3, discharge was
sustained. There was another interruption until July 12*, and discharge was
again sustained after this point. The hot, acidic effluent falls to the
beach below from a large pipe protruding from the cliff face (Fig. 7). A
dark brown and white foaming "mosto river" meanders down the beach and
empties into the surf. There is a pervasive odor of burnt molasses with a
suggestion of hydrogen sulfide. A strong prevailing alongshore current
generally carries the effluent plume to the west (Fig. 8). There are
occasional reversals when the plume swings around 180 degrees and hugs the
shore to the east. Strong wave action mixes the effluent with sea water,
which turns a dark reddish-brown and becomes opaque.
Since rum and rum effluents are normally referenced in gallons, this
denomination is used in preference to the metric equivalent.
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28
OBRERO
ATLANTIC OCEAN
PUERTO /
RICO ^
DISTILLERS
I Km
Mile
PUERTO
DE ARECIBO /
Figure 5. Map of Arecibo, P.R.
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29
Figure 6. A low altitude aerial photograph of the PRD plant at Arecibo,
P.R. The effluent is discharged onto the beach from a pipe
protruding from the eroded cliff. The meandering effluent stream
enters the surf zone to the west, creating a dark brown plume
which flows in a westerly direction downstream with the
prevailing alongshore currents.
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30
Figure 7. A close up of the rum effluent discharge from the PRD plant onto
the beach at Arecibo, P.R., looking west.
Figure 8. Mosto-stained surf downstream (west) from the discharge point for
the PRD plant at Arecibo, P.R., looking north.
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31
Field Studies
An initial field reconnaissance revealed certain conditions that would
control and limit the design of the research effort at Arecibo. These
conditions are: (1) the plume hugs the coastline and moves generally in a
westerly direction; (2) the effluent is discharged to a prevailing heavy
surf, coupled with a constant onshore trade wind blowing from the northeast,
making the area inaccessible for study by boat; (3) the coastal waters are
shallow near shore, making the area inaccessible to divers; (4) organisms
are not abundant in the sandy intertidal surf zone; (5) the rocky intertidal
zone hosts a diversity of organisms, especially in the tidepools that form
in the rocky outcroppings.
These conditions indicated that the rocky intertidal zone should become
the focus for preliminary field observations to determine the design of the
major experiments with mosto. Its value as a study site, however, was
impaired by movement of sand onto the beach. By the end of the study
period, sand had covered many of the intertidal communities under
observation.
Examinations of intertidal samples taken before and after resumption of
effluent discharge at the outfall site (Table U) and the control site (Table
5) revealed more consistent decreases in abundance of organisms at the
discharge site than at the control site. A census of tidepool fish revealed
obvious differences in species composition before and after resumption of
discharge (Table 6). Certain intertidal organisms, found to be absent or
rare near the outfall, were suspected of being excluded or limited by the
effluent, and were selected for the field and laboratory bioassay
experiments. These were the sea urchin Echinometra lucunter, which was
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32
Table 4. Intertldal samples taken at the discharge site at Arecibo before and after resumption of
mosto discharge
Station 1
Transect 1-B Transect
Before After Before
M VEHTEBH ATES
Limpets
Sea Worms"
Snails
"Beach Hoppers* (shriap)
Clams
Crabs
"Coat-of-Mail"
ALGAE
01 va
Fadlna
Chaetomorpha
Cladophora**
Hypnea
Cracilaria
Caulerpa
imphlroa
Bryocladla
Enteromorpha
10
25
28
11
170
0
0
0
27.2
12.3
Tr
0
Tr
0
0
0
0
0
0
1
3
16
0
0
Tr
0
Tr
Tr
0
Tr
0
0
0
0
4
100 .
4
33
57
2
0
0.6
4.6
29.8
19.6
1.2
1.0
19-3
Tr
Tr
0
2-B
After
0
0
0
0
9
0
0
Tr
Tr
Tr
0
0
0
Tr
0
0
0
Transect 1-W
Before After
0
58
62
52
112
0
8
1.4
0
105.6
23.6
4.8
0
0
0
1.3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Tr
•Includes nematodes
"•Includes Centroceras and Polysiphonia
ALGAE in grams wet weight INVERTEBRATES in numbers of Individuals
Source: Puerto Hioo Report
Tr = Trace
-------
33
Table 5.
Intertidal samples at an upstream control station at Areoibo before and after
resumption of nosto discharge
STATION 3
Transect 1-B
Before After
IK VERTEBRATES
Urchin
Sea cucumber
Limpet
Segmented worms
Snails
Beach shrimp
•Coat-of-Mail"
Unsegmented worms
Clams
Crabs
ALGAE
Sargassua
Padlna
Laurencla
Cladophora
Dletyopterls
Halynenla
Spyrldla
Enantiocladia
Jania
Plctyota
Anadyonene
Champ i a
Dlgonia
Valonia
Stypopodlum
Bryothamnlon
Heterosiphonia
Caulerpa
Amphiroa
Coelothriz
Cladophoropsls
21
1
2
50
100
133
3
9
0
0
31
Tr
6.8
78
Tr
3.2
Tr
6.6
Tr
0
0
0
0
0
0
0
0
0
0
0
0
11
3
0
16
281
27
0
11
2
0
28.3
Tr
Tr
31.6
0
7.4
0
0
0
Tr
Tr
0
Tr
Tr
0
0
0
0
0
0
0
Transect 2-B
Before After
19
2
0
168
21
267
0
0
0
0
55.4
.1
97
21.9
0
0
0
0
0
0.1
Tr
Tr
0
0
0
0
0
0
0
0
0
10
2
0
9
23
10
0
0
0
0
24.6
0
70.2
0
0
0
0
0
0
Tr
0
0
0
0
0
0
0
0
0
0
Transect
Before
1
1
0
100
93
382
0
0
10
0
21.9
.4
1.4
42.6
3-6
.4
0
184.2
18.7
8
.5
.7
.1
1-W
After
0
0
H
17
910
59
1
0
2
10
Tr
Tr
Tr
Tr
0
0
Tr
170.2
0
0
0
0
0
Transect 2-H
Before After
0
0
1
84
16
150
0
0
0
5
87.5
121.2
0
0
6.7
2.0
0
17
1
34
21
67
1
0
1
1
14.6
111.'
Tr
Tr
0
Tr
Tr
ALGAE In grama wet weight INVERTEBRATES in numbers or Individuals Tr = Trace
Source: Puerto Rico Report
-------
3*4
TABLE 6. Tldepool fish species observed on selected dates at Areelbo.
Hay 3 Hay 9 May 19 May 23" Hay 29 May 30 June 2» June 6 June 11 July lt»«»JuIy 5
Opicbthidae
Chlorhlnua avenaon
Carangidae
JOT. Jack *
Poaadasyldae
Juv. grunt +
lyphosidae
Unld. chub
Cbaatodontidae
Chaetodon atrlatua +
Ponacentrtdae
Eupenaoentrua leucoatlctua +
E. variabilla +
abudefduf aaxatllla +
A. taurus +
Mi«llidae
JUT. Bullet +
Labridas
Thalaaao
blfaaciatua
Dold. wrasse
Cllnldaa
Paraelinus fasclatua
Blemldae
Dnid. blenny
Blennius eriatatua
Oobiidae
Batfaygobius ap.
Aoantburidae
Aeanthurua ap.
Acanthurus coerulua
Botbidae
Bothua lunatua
Ballatidae
ju». flleflah
Rmber of Species, totals
12
12
11
•fSpeoiea present
•All fish observed were dead or exhibiting abnonaal behavior.
"Mosto discharge starts
•••Moato discharge stops
Source: Puerto Rico Report
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35
absent for about 2.5 km downstream from the outfall point, and the
"coat-of-mail" shellfish Chiton squamosus and mussel Brachiodontes exustus,
both rare in the impacted zone.
The absence and reduced abundance of the sea urchin Echinometra at
various stations in the plume is one of the effluent's most striking
apparent effects. Echinometra is believed to play an important role in
determining the structure of the rocky intertidal community by altering
surface areas and thus increasing available habitats for other organisms.
Thus the absence of Echinometra at the study site for a distance of about
2.5 km west of the outfall point could cause a significant change in the
structure and organization of the rocky intertidal community.
An extensive physical oceanographic study was undertaken to characterize
the general nearshore processes and water properties at Arecibo. Near-shore
circulation is controlled by the dominant effects of a strong alongshore
current system toward the west, generated by the prevailing winds. Only
short-term reversals occur. The effluent generally (about 70% of the time
during daylight hours) is dispersed along the shoreline to the west at a
rate of about 1.8 km/hr (maximum), with northeasterly winds blowing at
average speeds of between 10 to 15 knots. These observations confirmed
interpretations of aerial photographs of plume behavior.
Results obtained in the chemical analysis of the receiving waters at
Arecibo indicate that the impact of the effluent was not confined to the
immediate area of the outfall. Changes in BOD,, and COD were measurable
several kilometers downcurrent from the point of discharge (Tables 7 & 8).
The effluent changes the normal turbidity, temperature, dissolved oxygen and
salinity patterns in the area around the outfall. Measurements of trace
metals—Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn—in sandy beach sediments at
-------
36
Arecibo were low, and no significant differences were apparent between
controls and samples.
Characterization of the bottom sediment and beach materials indicated
that very little of the organic component of the effluent is held by these
sediments. Consequently it appears that the effluent remains in the water
column and is diluted progressively downstream for several kilometers.
Measurements of turbidity and inspection of the aerial photographs confirm
this observation.
Phytoplankton productivity in the coastal waters along the north shore
of Puerto Rico is low, as expected in tropical waters. No increase in
productivity was observed in the water column in the plume downstream.
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37
TABLE 7. Biochemical oxygen demand (BODq) at selected distances from rum effluent outfall at PRO, Areelbo
on various dates in 1978.
BOD
Location from outfall
July 7
No Discharge
July 12 July 11
Discharge
(relative to normal
current direction)
-2 km
-1 km
Outfall
Ocean entry
.15 km
.3 km
1.5 km
5.0 km
Note: BODc
2
1
1500
180
1
0
1
1
readings near the outfall
1
1
1660
6
1
0
0
0
were high
2
1
1100
5
i»
3
1
1
on all sampling dates.
1
1
1680
770
70
220
6
2
When mosto was
1
1
1590
670
50
13
0
0
not being
2
1
1660
950
100
78
16
6
discharged, an
unidentified clear liquid, smelling strongly of alcohol, was flowing and may well account for the high
BODg readings.
Source: Puerto Rico Report.
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38
TABLE 8. Chemical oxygen demand at selected distances frog rum effluent outfall In coastal
waters at PRO, Areelbo on various dates in 1978.
ODD, mg/1
Location from
outfall
(Relative to normal
current direction)
-2 km
-1 k
Outfall
Ocean entry
.15 km
1.5 km
5 km
July 14
104
97
-
114
110
97
53
July 21
73
53
24000
2000
1400
174
75
70
August 4
122
39
-
164
61
89
August 10
15
92
8448
3456
270
131
34
75
August 24
9
30
11155
99
147
96
134
Dash (-) indicates that measurement was not made.
Source: Puerto Rico Report
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39
BACARDI CORPORATION: CATANO AND THE ENSENDA DE BOCA VIEJA*
Site Description
The Bacardi plant (Fig. 9) is situated in the Palo Seco section of
Catano, one of the "municipios" that make up greater San Juan, on the neck
of land that separates the Bay of San Juan on the east from the Ensenada de
Boca Vieja, which receives most of the effluent, on the west. The Ensenada
is a tidal embayment, or estuary, whose shoreline the Bacardi outfall shares
with the former Schenley plant (now owned by Bacardi), the Palo Seco
Thermoelectric plant, the mouth of the Bayamon River, and Levittown (Fig.
10).
The grounds of the distillery do not abut the point of outfall on the
Ensenada de Boca Vieja. A pipe carries the waste stream from the plant to
the point of discharge (Fig. 11). The discharge is relatively constant, as
the plant operates about 300 days a year (except in late December and
January when the plant is shut down for employee holidays and equipment
cleaning and repair). With production at the main plant at about 60,000
proof gallons a day, and a ratio of about 6 gallons of effluent per proof
gallon of rum, the effluent load is about 360,000 gallons a day.
From the outfall pipe, the plume normally fans out in a westerly
direction; its configuration, however, changes as local current patterns
change. The water within the plume is reddish brown and opaque. Dissolved
oxygen measurements indicate that there is no dissolved oxygen in the plume
waters for several kilometers from the point of discharge. A strong odor of
hydrogen sulfide and the appearance of bubbles on the surface indicate that
•Bacardi's NPDES permit specifies outfall to the Bayamon River and San Juan
Bay.
-------
Figure 9. A low altitude oblique aerial photograph of the Bacardi Plant at
San Juan. The well-defined dark brown plume flows west from the
discharge pipe in the foreground.
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41
ATLANTIC OCBAN
ENSENADA DE
BOCA VIEJA
OLD
SAN JUAN
* BACARDI
BAHIA
DE
C ATA NO "^SAN JUAN
Figure 10. Map of San Juan showing location of Bacardi and the Old San Juan
Distillery (now owned by Bacardi).
Note: This map does not reflect recent man-made changes in the course of
the Bayamon River.
*
Figure 11. The Bacardi outfall structure extending into the Ensenada de
Boca Vieja *at Catano.
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42
bottom sediments are anoxic during plant discharges. Fish kills
were noted on occasions of three separate visits to this site.
VIRGIN ISLANDS RUM INDUSTRIES LTD.: ST. CROIX AND THE CARIBBEAN SEA11
Site Description
The VIRIL plant is located on the Diamond Estate about 2.0 km inland
from the southern and leeward shore of St. Croix, V.I. (Fig. 12).
Frederiksted lies about 6.H km to the west. The outfall pipe—formerly a
regional sewer duct—discharges the plant's effluent 600 m offshore at a
depth of 6 m. During the investigations, the effluent escaped from several
breaks in the pipe as well as from the pipe end {Fig. 13); thus there were
several plumes that coalesced downstream.
Several miles to the east of the outfall lies the Islands' industrial
complex: Hess Oil Virgin Islands Corporation, which includes a refinery and
tanker port, and the Martin-Marietta aluminum processing plant. The newly
constructed publicly owned treatment system (POTW) discharges its wastes to
the southeast of the VIRIL discharge.
The VIRIL plant discharges about 65,000 gallons of mosto a day with
little additional plant wastewater. Both BODj. and total solids content
per unit are high compared to PRO and Bacardi. VIRIL»s waste stream
contains only small amounts of fusel oils and aldehyde heads, since these
are burned in the boilers to generate heat for distillation.
-------
cFREDERIKSTED
ST. CROIX
VIRIL
DIAMOND
SANDY
POINT
CARIBBEAN SEA
I Mile
Figure 12. Map of St. Croix, V.I., VIRIL site.
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Figure 13. A low altitude aerial photograph of the VIHIL discharge plume along the southwest coast of St.
Croix. The dark brown plumes flow in a westerly direction with the prevailing current.
submarine outfall pipe was broken and leaking as seen by the four distinct inner plumes.
five plumes tend to merge downstream.
i
.
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Field Studies
While information from the studies at the VIRIL plant discharge site
tends to confirm and support the findings of the research at Arecibo and
Palo Seco, results from the Virgin Islands Report can only be considered
observational and inconclusive at the present time. The research specified
in the protocol was not adequately addressed in the information that has, to
date, been transmitted to EPA, and thus the Agency is treating the Virgin
Islands Report as observational.
At the VIRIL discharge site, a species census was conducted along three
transects at four substations at 100 m intervals along the plume and one
transect of four substations about 200 m upcurrent (east) from the discharge
point. Investigators found that the bottom substrate had been denuded of
turtle grass (Thalassia testudinum) in the immediate outfall area, with
growth of turtle grass diminished to a distance of 0.8 km downstream (west)
of the outfall. The cause of the bare patches, where turtle grass would
normally be expected, cannot definately be ascribed to the rum effluent, or
to any other factors. Investigators believed, however, this could be a
function of the mosto-darkened waters (high turbidity) impeding the passage
of light to the sea floor and other effects of the effluent.
The sea urchin Tripneustes esculentes, a different species from the
urchin studied at Arecibo, was selected for study in the Virgin Islands on
the basis of its scarcity on the sea floor near the outfall and up to 2 km
downcurrent. Investigators believed the scarcity of indigenous benthic
organisms, including the Tripneustes, near the outfall might be associated
with the denuding of the turtle grass beds. Subsequent bioassays in the
laboratory showed the effluent to be directly toxic to the urchins in all
concentrations tested.
-------
Divers at St. Croix found that the waste "plume" distributes itself
vertically throughout the water column, from sea floor to surface. The
plume is clearly visible by air to a point about 6 km west of the outfall.
Upstream from the outfall, the dissolved oxygen readings were generally over
6.0 mg/1 (normal). Dissolved oxygen was found to be depressed downstream.
BIOASSAY EXPERIMENTS
In Puerto Rico, bioassay tests were conducted in the field on two marine
invertebrates, the urchin Echinometra lucunter at Arecibo and the blue crab
Callinectes sapidus at the Bacardi site. In the laboratory, bioassays using
mosto in varying concentrations with seawater were conducted on these two,
plus two additional invertebrates, the "coat-of-mail" shellfish Ch j ton
squamosus and the mussel Brachidontes exustus.
Field Bioassays
A series of tidepools within 150 m of the outfall point at Arecibo was
designated for intensive study of the sea urchin Echinometra lucunter (Fig.
Sea urchins were transplanted to the tidepools from nearby areas on
three occasions, under three different sets of conditions:
First transplant: May 3, before resumption of plant operation (after a
shutdown period of nearly a month). Twenty days after the transplant,
of the urchins survived (Table 9).
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N
ATLANTIC OCEAN TIDEPOOL 2
TIDEPOOL 1
TIDEPOOL 3
EFFLUENT STREAM
X LOW TIDE
SCALE
Figure 1U. Location of tidepool studies at Arecibo, P.R.
Source: Puerto Rico Report
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TABLE 9. Survival of transplanted Echinoaetra lucunter in tldepools before resumption of effluent discharge at PHD.
Arecibo.
Date
5/3/78
5/1/78
5/19/78
5/23/78"
Cumulative
t of Days
0
1
16
20
Number of Individuals
Tidepool 1 Tldepool 2
100 50
88 50
89* 19
46
Tldepool 3
100
86
90*
84
Tidepool 1
100
79
74
72
Tldepool 5
100
92
69
46
Average Per-
cent in all
Tldepools
-
891
8«(
70J
•Counts higher than previous ones were due to exceptional water clarity resulting In improved counting efficiency.
••Effluent discharge resumed.
Source: Puerto Rico Report
TABLE 10. Effects of effluent on dissolved oxygen levels in tldepoola at PRO, Arecibo.
Estimated*
Event/date Hosto Cone, (t)
Before Discharge
5/9/78
5/19/78
5/23/78
Initial Discharge
5/29/78
6/6/78
Sustained Discharge
without wave exchange
6/12/78
6/20/78
6/27/78
with wave exchange
6/21/78
6/23/78
Discharge Discontinued
7/3/78
7/4/78
7/10/78
0
0
0
0.1
-
0.68
0.12
0.42
0.01
0.25
0
0
0
TIDEPOOL »1
Temp. (°C) 02 (PP">
28.0
29.5
29-0
29.0
31.0
32.0
32.5
29.0
28.0
28.3
33.5
31.5
28.5
11.2
10.8
6.2
4.5
2.5
0.3
1.8
0.4
5.2
5.3
8.5
6.8
6.3
CONTROL TIDEPOOLS
Temp. (°c) 02(ppm)
-
-
-
. _
-
31.5 12.5
32.5 7.0
30.5- 7.2
28.0 6.3
28.2 6.8
— —
28.8 6.0
28.5 5.9
•Estimated by colorlnetry
Source: Puerto Rico Report
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Second transplant: After beginning of plant operation and sustained
effluent discharge. All urchins were dead after 7 days (Fig. 15).
Third transplant: During shut-down period between July 3 and July 14.
Forty percent (or more) of the urchins survived after 7 days (Fig. 15).
Concentrations of mosto could not be exactly determined, but were
estimated, by colorimetry, for Tidepool #1 (Table 10). In general, survival
increased slightly in tidepools located successively further from the
outfall point.
Important differences between dissolved oxygen levels in tidepools with
and without mosto were recorded (Table 10). Generally, the effect of the
effluent was to depress oxygen concentration so that during low tides, when
pools may be stranded, dissolved oxygen levels approached zero. This
condition was a reversal of normal daytime low tide situations, where
photosynthetic activity by algae will normally supersaturate stranded pools
with dissolved oxygen. This critical oxygen concentration difference at
least partly contributed to the observed mortalities of tidepool organisms
after effluent discharge resumed.
Laboratory Bioassays
Laboratory bioassays used pure mosto—that is, distillery slops with no
other waste stream components—in concentrations from 5% to .01/6 (or 1:20 to
1:10,000 dilutions in seawater) in an aerated, flow-through assay system.
The four invertebrates used in the bioassays in Puerto Rico responded
differently, as might be predicted, indicating that certain invertebrates
are more sensitive to mosto (per se) than others. The sea urchin
-------
50
100
_J
I
>
cr
z>
CO
UJ
O
cr
UJ
Q.
Effluent stream not flowing-
Effluent stream flowing
Tide pool I •
Tide pool 2 O
Tide pool 3 A
I 234567
EXPERIMENT DURATION IN DAYS
Figure 15. Survival of transplanted Echinometra lucunter in tidepools
at Arecibo with and without effluent discharge.
Source: Puerto Rico Report
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51
Echinometra lucunter and the "coat-of-mail" shellfish Chiton squamosus were
more sensitive than the other test organisms to mosto, as indicated by
mortality in both species (Fig. 16 & 17) and altered behavior in Echinometra
(Fig. 18) at the lowest concentrations tested. These observations were
supported by field data from Arecibo where both organisms were absent or
rare in impacted areas. Concentrations of .01% or more for a distance of
about 1.5 km downcurrent from the outfall were estimated by colorimetry.
The mussel Brachiodontes exustus and the blue crab Callinectes sapidus
were more resistant to the rum slops. These organisms survived in the
laboratory in seawater containing 0.5% mosto (Fig. 19 & 20). The 96-hour
LC-., the ("lethal concentration" at which half the organisms die and half
survive through 96 hours) was calculated to be .087$ for the urchin
Echinometra lucunter. Allowing for an "application factor" of one order of
magnitude (the conventional means of calculating a dilution level at which
non-persistent pollutants might be safely discharged into receiving waters),
a dilution of 87:1,000,000 or, rounding off, 1:10,000 would be required in
order for this species to avoid being adversely affected by the discharge.
The mussel Brachidontes was present in the lower zone of the intertidal
rocks in the heavily impacted area at Arecibo (PRD). Mortalities were
observed, however, during the first weeks of effluent discharge, and the
mussels disappeared from the upper zone of the intertidal rocks. Production
of the byssal threads by which the mussels attach to a substrate was found
altered in a laboratory bioassay (Fig. 21). The greater number of byssal
threads seen in the lowest concentration tested is probably a reaction that
indicates the mussels have sensed a change in their environment. It cannot
in any case be seen as an improvement in the condition of the mussels.
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52
o:
z>
CO
UJ
o
tr
UJ
Q.
100
50
5 % Mosto
0.5% Mosto
0.05% Mosto
Control
I
I
I
24 48 72 96
EXPERIMENT DURATION IN HOURS
Figure 16. Bioassay of Rum Distillery Waste (mosto) Seawater: Survival of
urchin, Echinometra lucunter, (n = 60 individuals per dilution).
100
cr
z>
CO
UJ
o
(T
UJ
Q.
Figure 17.
50
5 % Mosto
0.5 % Mosto •
0.0 I % Mosto A
Control A
I
I
I
24 48 72 96 I20 I44 I68
EXPERIMENT DURATION IN HOURS
I92
Bioassay of Rum Distillery Waste (mosto) in Seawater: Survival
of Chiton squamosus (n = 60 individuals per dilution).
Source: Puerto Rico Report (Fig 16 and 17)
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53
DID NOT
RIGHT
•i
120 -
n*38
n*0
5% Mosto O
0.5 % Mosto •
0.05 % Mosto A
Control A
35
to
o
z
o
o
111
to
UJ
CD
Z
I-
X
CD
or
a
2 30' -
24 48 72 96
EXPERIMENT DURATION IN HOURS
Figure 18. Bioassay of Rum Distillery Waste (Mosto) in Seawater: Effect
on Righting Behavior of Echinometra lucunter.
100
or
z>
CO
LJ
o
cc
UJ
Q.
50
5% Mosto O
0.5 % Mosto •
0.05 % Mosto A
Control A
_L
J_
24 48 72 96
EXPERIMENT DURATION IN HOURS
Figure 19. Bioassay of Rum Distillery Waste (Mosto) in Seawater: Survival
of the Mussel, Brachidontes exustus (n = 60 individuals per
dilution).
Source: Puerto Rico Report (Fig. 18 and 19)
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54
SOO
cc
u
CO
UJ
o
£E
UJ
OL
50
5 % Mosto O
0.5 % Mosto •
0.0 I % Mosto A
Control A
I
I
I
I
24 48 72 96
EXPERIMENT DURATION IN HOURS
Figure 20. Bioassay of Rum Distillery Waste (Mosto) in Seawater: Survival
of the Blue Crab, Callinectes sapidus (n = 30 individuals per
dilution).
O
O
IT
£L
20
U)
Ul
<
UJ
Figure 21.
it-S7
5% Moito O
0^ % Mosto •
0.05% Mosto A
Control A
n»58.
24 48 72 96
EXPERIMENT DURATION IN HOURS
Bioassay of Rum Distillation Waste (Mosto) in Seawater: Effect
on Byssal Thread Production by the Mussel, Brachidontes exustus.
Source: Puerto Rico Report (Fig. 20 and 21)
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55
Callinectes sapidus was highly resistant to mosto in the laboratory, but
did not survive in the field bioassay experiments at Palo Seco (Bacardi).
Secondary effects related to very low dissolved oxygen levels and to the
presence of hydrogen sulfide in the plume at Palo Seco probably caused the
crabs to die in the field.
In the Virgin Islands, bioassays were conducted using the sea urchin,
Tripneustes esculentus, in mosto concentrations (VIRIL mosto) ranging from
.T\% to .025%. Dissolved oxygen levels, despite constant aeration at the
mixing tank, dropped severely in test aquaria, and all the urchins were dead
well before the full 96-hour exposure. A prolific "growth" of a white slime
was observed over all substrates in the aquaria. Increased aeration did not
succeed in bringing up the dissolved oxygen level appreciably, but seemed
only to enhance the growth of the slime, thought to be microbial in nature.
No conclusions could be drawn from these bioassays.
DISCUSSION OF TROPICAL MARINE ECOSYSTEMS AND ORGANIC EFFLUENTS
Each of the three locations under consideration—the north coast of
Puerto Rico, the coastal embayment near San Juan, and the shallow, southern
shore of St. Croix—is unique, as is each marine ecosystem. There are,
however, commonalities. The sites are within a few hundred kilometers of
each other and all are in tropical waters. Thus it is possible to make
several generalizations on the differences between tropical waters and
cooler seas. Obviously, the waters are warmer than the northern temperate
seas. In the warmer tropical waters there are a greater number of different
species than in cooler waters, but fewer individuals of each species.
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56
Most of the individual organisms in colder seas are members of the plankton
community that forms the base of the food web. It is this abundance—the
richness in microscopic plants and animals—that frequently gives to cold
oceans their greenish opaqueness that we see in contrast to the clear blue
of the tropical sea, where details may be visible to perhaps 10 fathoms in
depth.
The tropical marine ecosystem likewise is more stable and diverse than
the ecosyterns of cooler oceans. The indigenous organisms survive close to
the upper limit of their thermal tolerance and are less able to withstand
"stress," or disruption. The comparative scarcity of planktonic organisms
(particularly phytoplankton) has led some observers to characterize these
waters as "nutrient poor" and subject to improvement by the addition of
effluents. Spokesmen for the industry have contended that since untreated
rum effluents have been discharged at these sites for many decades, these
discharges may already constitute an important food source in the ecology of
Caribbean waters which cannot be removed without significant damage. A
12
further assertion is that the receiving waters are "nutrient-deficient".
If the receiving waters are "nutrient-deficient", this is so only in
comparison with cooler waters in which many features are at variance. The
limiting nutrients, moreover, that would theoretically enable the tropical
sea to support a more abundant plankton population and hence a richer flora
and fauna and greater biomass, are not carbon compounds, but inorganic
nutrients such as nitrogen, phosphorus, and other trace materials.
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57
It is not realistic, then, to anticipate successfully mimicking the
effects of upwelling—the process by which cooler waters rich in inorganic
nutrients rise from the depths of the sea to the surface, where these
nutrients can be put to use—by addition of "rich" organic waste materials
such as mosto to the coastal waters. The major problem with the addition of
rum effluent to seawater is its high levels of organic carbon compounds and
high BOD (./COD. The carbon-rich effluents cause a lowering of the
dissolved oxygen level in the receiving waters and, in some cases, result in
anoxic conditions. Thus instead of enhancement through the addition of rum
effluent, degradation occurs to an extent that depends upon physical
conditions in the receiving waters. The heterotrophic microorganisms—
consumers of complex organic substances—that thrive in the waste stream
deplete the oxygen supply and thus tend to exclude other indigenous
organisms that normally balance this ecosystem.
The potential effects of any proposals to dilute rum wastewater through
an ocean outfall are at best poorly understood. Little is known about the
impact of a long-term discharge of a dilute organic-rich effluent such as
mosto on the tropical marine environment. Studies and field observations at
existing outfall sites revealed damage to marine organisms. Based on the
data presented in the Puerto Rico Report, dilution could not reasonably be
expected to render mosto discharges beneficial to the receiving waters.
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58
SECTION 5
¥ASTEWATER TREATMENT AND UTILIZATION TECHNOLOGIES13
INTRODUCTION
A study of technologies available for effluent treatment and utilization
examined many options, including discharging the wastes to public treatment
works, aquaculture, ocean discharge, land application, evaporation, and
biological treatment. These wastewater treatment and by-product
recovery/utilization technologies were found to be generally applicable to
rum effluents. Numerous other technologies were investigated and found to
offer little promise for treating rum distillery wastewater.
Summary:
Discharge to a publicly owned treatment works (POTW), aquaculture and
ocean discharge: Discharge to a POTW was found not to be a feasible option
for any of the distillers. The effluent was found unsuitable for
aquaculture systems, primarily because of the extremely high BOD_.
Further research may yield new possibilities in this area. Although the
Clean Water Act does not permit ocean discharge of untreated industrial
wastes, scenarios for ocean discharge were developed for all three
distillers.
Land application: Agricultural utilization and land farming appear to
be practical disposal options for at least one distiller, PRO. Land
reclamation is not a viable disposal option for any of the three
distillers. The combination of potentially available land and a dry climate
on St. Croix suggests land farming as a disposal option for VIRIL. Bacardi,
located in greater San Juan, is less favorably situated than the other
distillers for land application.
Evaporation: A review of available literature indicates that
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59
evaporation of mosto to condensed molasses solubles (CMS) is a
technologically feasible treatment option. The utilization or ultimate
disposal of CMS, however, may not be economically practical. Estimates of
Puerto Rican CMS consumption suggest that approximately 18? of the total
theoretical CMS production could be used as an animal feed supplement if
incorporated in the feed at 5% by weight. If the CMS were incinerated,
potassium salts could be recovered from the ash. The market for potassium,
however, is uncertain. CMS also can be used as a raw material from which to
produce an organic nitrogen-phosphorus-potassium (N-P-K) fertilizer.
Biological treatment: Rum processing wastewaters can be biologically
treated and the excess sludge can be disposed of adequately. The most
economical treatment system probably would be anaerobic digestion followed
by an aerobic system, such as an activated sludge process. The Anamet
system, an anaerobic/aerobic system, is presently under study at PRD, and
appears promising. The dark color of the effluent would continue to be of
concern in any conventional biological treatment system.
Outline:
Disposal to a POTW
Aquaculture
Ocean Disposal
Disposal by Land Application
Agricultural Utilization
Land Farming
Evaporation, with CMS By-Product
Production of CMS
Utilization of CMS as a Livestock Feed Additive
Use of CMS as an Intermediate Product
Incineration
Potassium recovery from incinerator ash
Organic fertilizer production from CMS
Biological Treatment
Aerobic Treatment of Mosto
Anaerobic Treatment of Mosto
Combined Anaerobic/Aerobic Treatment of Mosto
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60
DISPOSAL TO A PUBLICLY OWNED TREATMENT WORKS (POTW)
Disposal to a POTW is frequently considered when specific waste
treatment options are technically or economically infeasible for a
particular industry. It is then necessary to consider whether such a
facility has the capacity to treat the waste effectively. Despite a number
of problems associated with high-strength wastes such as mosto,
possibilities for disposal to a POTW were examined for each of the three
distillers under study.
Bacardi;
The Bacardi Corporation is located within the city limits of Catano,
where there is presently no regional POTW. Plans have been developed and
approved for a wastewater collection and sewage system (the Bayamon
wastewater system) capable of accommodating population and industrial growth
through the year 2020. This primary treatment facility will discharge its
effluent through an ocean outfall. The Bacardi wastewater, if discharged to
the Bayamon wastewater system, would pass through only partially treated.
The BOD,, would be reduced very slightly, if at all, and thus adequate
pollution abatement would not be achieved.
PRO
Puerto Rico Distillers is located on the western edge of Arecibo, a city
which currently discharges its domestic waste streams directly to the
ocean. Construction has reportedly begun on a trunk line system to route
wastewaters to a primary waste treatment plant (also under construction)
located on the eastern side of Arecibo. There are reportedly no present
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61
plans to install a trunk line to the western extremities of the city, where
the distillery is located. Even if collection lines were available, the
mosto discharged from PRD, virtually identical to that of Bacardi, would
pass through the POTW with minimal treatment.
VIRIL
A small (0.5 million gallon/day) POTW with secondary treatment is
located within several kilometers of the distillery. Secondary effluent is
discharged to the Caribbean Sea through a 2,7^0 m outfall pipe.
VIRIL and POTW personnel conducted preliminary discussions concerning
the possibility of discharging mosto to the POTW. Rum effluent could not be
accepted for treatment because of its high strength.
AQUACULTURE
Aquaculture, in concept, has several advantages over other utilization
or by-product recovery technologies: little or no effluent pretreatment is
required; considerable potential exists for recycling nutrients from the
waste into a harvestable crop.
A great deal of study would be necessary to determine how mosto could
best be used in an aquaculture project and what species or chain of species
would utilize the slops efficiently and constitute a harvestable crop.
Questions as to design and location of physical facilities and projected
capital and operating costs likewise would require detailed study.
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62
Two noted authorities in aquaculture were contacted for information on
the potential for using mosto in crustacean and higher organism aquaculture
systems. Both agreed that the mosto material is not adaptable as a feed
ingredient in such aquaculture systems. Their evaluation was based on
several factors, including the following:
1. The BODR and COD in mosto are very high, indicating that the mosto
is very high in organic carbon compounds;
2. High carbon content is further substantiated by high carbohydrate
content;
3. Presence of significant amounts of carbon compounds will enhance
growth of heterotrophic bacteria;
U. Levels of copper in mosto (average ^330 ppb) are toxic to most
shellfish and acutely toxic to the larval stages.
OCEAN DISPOSAL
While the Clean Water Act does not provide for ocean discharge of
untreated industrial wastes in cases where a viable treatment technology has
been identified, this option has been explored at the request of the
industry. As noted in Section 4, possible benefit to the receiving waters
suggested by the rum industry could not realistically be expected. Thus an
exception to the Clean Water Act on the basis of assumed water quality
enhancement could not be a valid consideration. We have, nevertheless,
considered various factors related to ocean disposal.
Effective use of the ocean to assimilate wastewater depends on both
environmental and engineering factors. Important environmental factors are
ocean depth, currents, bottom materials and configuration, and density
stratification. Engineering must allow for good jet mixing, taking into
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63
account these environmental features as well as chemical and physical
characteristics of the specific waste stream.
A typical outfall consists of a submarine pipeline roughly perpendicular
to the shoreline. In shallower water, it is buried under rip-rap for wave
protection and at greater depths it is laid on the ocean floor with ballast
rock. At the end there is usually a diffuser section, a manifold with many
small holes to distribute the flow over a large area of the ocean floor.
Two noted authorities in the design of submarine outfalls were contacted to
assist in evaluating the potential for continued ocean disposal. It was
estimated that instantaneous dilution of mosto through a properly designed
diffuser would be in the range of approximately 1:50 to 1:100. The density
of mosto, approximately that of seawater, would aid in dispersion. Once
discharged, ultimate dispersion is a function of natural oceanic turbulence,
which could be assessed only through procedures beyond the scope of the
study.
Bacardi has suggested that, rather than construct its own outfall, it
would connect to the proposed Bayamon primary wastewater treatment plant
(POTW). The Bayamon outfall would extend 1,215 m into the Atlantic Ocean to
a depth of about 48 m. By connecting to the Bayamon outfall, the Bacardi
effluent would mix with the primary treated effluent from the proposed POTW;
thus, the Bacardi effluent would be "diluted" with sewage, not unpolluted
water. Such "dilution" might add to pollution problems, not mitigate them.
Additional dilution with seawater could be expected upon discharge to the
ocean through the diffuser.
In order to discharge its waste at a depth approaching that proposed by
Bacardi, PRD would have to design and construct an outfall extending 530 m
into the Atlantic Ocean to reach a depth of approximatley 46 m. Due to the
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gentle slope of the ocean floor, VIRIL would have to construct an outfall
extending 6,690 m into the Caribbean to reach a depth of *46 m. Both the PRD
and VIRIL hypothetical outfall designs could be expected to achieve initial
dilutions between 1:50 and 1:100.
The current practice in outfall design for large systems is to build
long pipelines (3 km) on the open coast to water depths of 70 m, and to
install large multiple-port diffusers. These can achieve large initial
dilutions (1:100) and result in the submergence of the entire wastewater
plume. It is apparent that none of the ocean outfall scenarios described
above for the distillers meets these criteria for accepted practice for
outfall design and, thus, may not achieve initial dilutions of 1:100. This
study did not investigate the biological effects on the marine environment
of discharging mosto through proposed ocean outfalls because such
investigations would have required large expenditures of both time and
resources. However, bioassay data from the biological portion of the study
suggested that a dilution of 1:10,000 would be required to avoid adverse
effects on certain marine organisms.
DISPOSAL BY LAND APPLICATION
Soil, with its tremendous surface area and varied microbial population,
has been viewed as a physical, chemical, and biological filter for waste
materials. The waste is retained by the soil matrix, and the organic
fraction of the waste eventually is decomposed by the soil microorganisms.
Land application is a practice whereby wastes are applied to the soil
surface and incorporated into the top 15 to 30 cm of soil.
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65
As in farming practices, only the surface soil is utilized, and the process
of assimilation' is aerobic. Optimal degradation of the added wastes
requires environmental conditions similar to those needed for raising a
crop—adequate amounts of sunlight, water, nutrients, and oxygen—and
similar types of equipment.
"Land application" comprises several options. Principal among these are
the following:
1. Agricultural Utilization - as a soil amendment, utilizing the
available organic and inorganic nutrients to enhance the growth of
certain crops.
2. Land Reclamation - as a soil amendment to add organic and inorganic
nutrients to distressed or submarginal lands.
3. Land Farming - as a means to dispose of wastes on a plot of land, set
aside for the purpose of disposal, whereby the organic constituents
are degraded by natural processes (oxidation and reduction via
sunlight) and the inorganics are trapped within the surface soil
matrix.
Land reclamation is usually employed in situations where waste
generators are near distressed or heavily mined areas; such lands were not
known to exist within any practical distance of any of the distilleries, and
this option, therefore, was not evaluated.
Agricultural Utilization
Destilleria Serralles, in Mercedita, Puerto Rico, has been discharging
its mosto to approximately 160 hectares (ha) of sugar cane fields since 1935
(Fig. 22).
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66
Figure 22. A low altitude aerial photograph of the Serralles Plant in
Mercedita surrounded by sugar cane fields where the effluent
from the plant is discharged as fertilizer along with irrigation
water.
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67
The mosto Is combined with other plant wastes, achieving final dilutions
ranging from 1:2 (other plant wastes/mosto) to 1:5. This combined stream is
pumped to a central irrigation station which further dilutes the wastes
prior to final field discharge. The combined plant wastes at this point are
diluted approximatley two-fold. Supplemental irrigation water is supplied
by an adjacent river north of the plant. In 1975, a system of peripheral
ditches was constructed to prevent mosto runoff during periods of heavy
rain. Although soil and groundwater monitoring programs have not been
established, no deleterious effects have been reported for either the soil
16
or sugarcane.
Of the three rum distillers considered within this study, PRD, located
within about 7 to 10 kilometers of several thousand hectares of government
owned sugarcane fields, is most favorably situated to take advantage of this
disposal method.
Neither Bacardi nor VIRIL has similar nearby access to sugarcane or
other crops amenable to irrigation.
Land Farming
As an alternative to agricultural utilization, the feasibility of
establishing a land farming program for each of the three distillers was
investigated. Two scenarios were developed: transportation of mosto
overland via tanker trucks; and, transportation of mosto via pipeline.
Based on a maximum annual application rate, land requirements for mosto
disposal for Bacardi, PRD, and VIRIL, were estimated at 111 ha, 51 ha,
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63
and 24 ha, respectively. This loading rate was estimated to be equivalent
to 270 dry kg/ha; site life was estimated to be a MniausD of 25 years based
on copper concentrations. If copper were removed or reduced, the next
limiting metal, zinc, would extend the site Life to 160 years.
EVAPORATION WITH CMS BY-PRODUCT
Evaporation of aosto as a treatment technology Bust be considered as a
function of utilization and disposal options for the resultant products,
CMS car? be used as a livestock feed supplement or as a source of organic
fertilizer, or it may be incinerated. In the latter ease, it has some value
as a fuel source, Potassium salts, marketable as a fertilizer additive, can
be recovered from the ash*
Production of CMS
The technology for evaporation of cane molasaea stillage has been
successfully demonstrated and is eonRsonplace in Europe, With few
exceptions, however, it is applied to citrus rather than cane molasses
residues In the U.S. Typically, CMS has a solids content in excess of 50?,
ft large pilot plant was installed at the Bacardi distillery in Catano in
August 1977, and became fully operational in July 1978. Currently it is
being evaluated to determine optimum operating conditions for CMS production,
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69
Utilization of CMS as Livestock Feed Additive
The composition of CMS varies with type of molasses used and, to a
lesser extent, type of fermentation processes and products involved. Beet
derived CMS has been shown to be a more desirable feed additive than cane
derived CMS because of its higher protein content C\S>% for beet vs. U>6 to 6%
for cane).
A review of available literature indicated that cane derived CMS could
be safely incorporated into the diets of cattle and laying hens at the five
percent level as an additive or as a molasses substitute. Feed conversion
inefficiencies in cattle and litter caking and staining in laying hens are
problems that would need to be addressed.
Additional problems are apparent in the area of marketing. European and
U.S. distillers have demonstrated that CMS can be successfully marketed.
Puerto Rico and the Virgin Islands, however, have potentially limited
domestic CMS markets. Starting from the annual quantity of formulated feed
manufactured in Puerto Rico (St. Croix was assumed to produce a negligible
amount of feed) and assuming incorporation at the five percent level, it was
estimated that an annual theoretical maximum of 18^6 of the CMS produced by
all three distillers could be utilized in Puerto Rico. The actual maximum
may be significantly lower, however, due to customer and manufacturer
reluctance to accept a new product.
Feeding tests, moreover, suggest that CMS is technically less adequate
as a feed ration than cane molasses and that to balance this disparity, CMS
market prices would have to be about 5Q% lower than those for cane
17
molasses. CMS costs, beyond production, would include those for
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70
movement to dockside, storage, and carrier loading for shipment to the U.S.
A, possible additional cost would be for transport of the CMS from mainland
ports to livestock feed producers and users.
Use of CMS as an Intermediate Product
Uses of CMS as an intermediate product for incineration, (which may be
followed by potassium recovery), and as a raw material for organic
fertilizer were evaluated.
Incineration—
Incineration of mosto theoretically may be accomplished either directly
in the waste stream or after concentration. The advantage of concentration
is anticipated cost savings, on both total equipment investment and
operating costs. Engineers and manufacturers of incinerating equipment have
observed that it would be several times more expensive to incinerate slops
directly than to pre-concentrate and then incinerate.
Thus, any cost-effective incineration plan is likely to include an
evaporation or concentration step.
Calculations performed on an analysis for a typical mosto stream
indicated that autogenous combustion (combustion without the need for a
continuous supply of auxiliary fuel) can take place with a feed total solids
(TS) concentration as low as 35?. A TS concentration significantly above
35% was determined to be desirable to increase heat recovery in a waste heat
boiler and to decrease the size of the incinerator.
The literature reviewed contained no descriptions of pilot studies
performed under constant operating conditions. Both Bacardi and PRD
evaluated incinerator systems, but these differed in major features.
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71
Thus an economic analysis of each on a comparable basis was not possible.
Potassium Recovery from Incinerator Ash—
Incinerator ash is basically a crude potash containing potassium salts
and impurities such as calcium and magnesium salts, silica, traces of iron
and manganese, and unburned carbonaceous particles. Ash has been reported
to contain 37$ potassium (expressed as K_0). Potassium salts generally
have been reported to make up 65% to 70? of the ash.
Based on pilot plant studies in India, it was estimated that a
distillery discharging 72,000 gallons of mosto a day could recover 3.17
metric tons of potassium salts (expresed as K?0).
The Puerto Rican market for potassium was examined. Based on an
estimated yield of 0.024 kg ash to a liter of mosto (0.2 Ibs./gal), an
annual total of 5,000 t of potassium salts could theoretically be generated
by all three distillers. Based on average consumption figures of potash and
potassium as direct application materials, annual usage was estimated at
1,500 t. This is about 30$ of the estimated total quantity of such
materials that could theoretically be produced by the three distillers if
all of their mosto were used in this manner.
Organic Fertilizer Production from CMS—
The Japanese have developed a process for creating an organic complex
N-P-K fertilizer utilizing CMS as a raw ingredient. Through a series of
chemical reactions involving CMS, sulfuric and phosphoric acids, and
ammonia, a dried granulated product can be produced. It was estimated that
the three distillers could produce approximately 5^,000 t annually.
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BIOLOGICAL TREATMENT
During the last twenty years, there has bean extensive r-esearch and
development in biological treatment of wastes from the distillation and
fermentation industries, including wine and beer as well as beet and cane
molasses derivatives. A thorough review of the literature was conducted to
evaluate the various biological processes.
Aerobic Treatment of Mosto
Applications of conventional aerobic systems were reportedly beset with
problems. Both the trickling filter and activated sludge processes, when
used by themselves with undiluted mosto, were found unsatisfactory.
Anaerobic Treatment of Mosto
Anaerobic treatment offers several significant advantages over aerobic
(especially for high-strength wastes such as mosto) including the following:
1. Energy requirements for digesters are small compared with those of
their aerobic counterparts.
2. Sludge generation is 5Q% to 80? less than for aerobic treatment.
This markedly reduces costs associated with ultimate sludge handling
and disposal.
3. Anaerobic treatment generates methane gas which can be recovered and
used as an energy source.
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73
ifi
In a 1971* study conducted by EPA, anaerobic digestion, used as a
sole treatment method for rum distillery wastewaters, was reported to be
partially successful. Other researchers similarly have experimented with
anaerobic digestion, varying loading rates, mosto dilution, retention times,
and other parameters. Presently the effluent remaining after anaerobic
treatment of rum distillery mosto would require further treatment.
Combined Anaerobic/Aerobic Treatment of Mosto
The effluent resulting from anaerobic digestion has been demonstrated to
contain high concentrations of BOD,. (2,000 to 10,000 mg/1) as well as
immediate oxygen demand and thus is not suitable for direct discharge to
surface waters. Further treatment can be effectively accomplished through
conventional aerobic processes, specifically, activated sludge.
If a treatment system consists of anaerobic digestion followed by an
aerobic process, such as activated sludge treatment; both systems will
produce sludge which must be handled and disposed of ultimately. If
adequate land is available, sludge may be thickened and dried in lagoons.
If land is in short supply, sludge thickening can be followed by vacuum
filtration and incineration, with ultimate land disposal of the ash.
Many such combined anaerobic/aerobic systems are in existence. One such
system, known as Anamet (licensed by AB Sorigona of Sweden), has been shown
to be particularly effective on high strength fermentation, carbohydrate,
and nitrogenous wastes. This proprietary process differs from other
biological systems in that it has all of the following characteristics:
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1. Use of a closed tank for the aerobic stage rather than an open pond;
2. Recovery of methane gas for fuel;
3, Recycle of digester sludge within the anaerobic process and recycle
of waste-activated sludge from the aerobic step back to the digester
4. Optional nitrogen stripping with recovery of ammonium salts.
5. Low energy consumption. -
According to representatives of Sorigona, the results of existing Anamet
plants operating on wastewaters similar to those of rum distilling have been
excellent, with BODj. reductions of up to 99$ being achieved. After
visiting the facilities of PRD and laboratory testing of the mosto,
Sorigona's representatives expressed the belief that mosto could be treated
successfully with Anamet. An Anamet pilot plant was set up at PRD and began
operating in July of 1978. Preliminary results are not yet available from
this pilot study (Figs. 23, 24).
In addition to the treatment systems discussed, there are a number of
process modifications that can result in considerable pollutant reduction.
These are discussed in Section 3 of this report.
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75
Figure 23. Photograph of the Anamet
pilot plant in operation at PRD.
The engineering firm of the AB
Sorigona of Staffanstorp, Sweden, is
conducting the test. Test data were
not currently available.
o
03
c
z
LJ
•2.
^^
0.
U.'
CJ
03
O
cr
UJ
H SOLID WASTE
cr
HJLU
1-0
coo
[SOLUBLE WASTE
EXTRACELLULAR
ENZYMES
ACID FORMING
BACTERIA
ORGANIC ACIDS* NH
METHANE FORMING
BACTERIA
[METHANE-t-CARBON DIOXIDEJ
! [AMMONIA REDUCTION!
REMAINING
ORGANIC WASTE+ 02+N
ACTIVATED
SLUDGE
[CLEANED WASTE WATER
Figure 2U. Diagram of Anamet system.
Source: Sorigona trade brochure.
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76
SECTION 6
ECONOMIC ASSESSMENT19
INTRODUCTION
An economic assessment of the Puerto Rico and U.S. Virgin Islands rum
industries was conducted to describe their economic significance to their
respective economies and to analyze the economic implications of wastewater
treatment.
Summary:
The rum industry is an important and growing source of government
revenues in 1978 contributing 12.7$ of general fund receipts in Puerto Rico
and 16.4J in the Virgin Islands. Additional benefits to the economy are
seen in the industry as a source of employment and in the support industries
related to rum production.
In order to assess the economic impact of wastewater treatment on the
distilleries under consideration, a system of economic model plants was
developed. Plants of high or average efficiency were found viable after
relatively large expenditures for wastewater treatment.
Outline:
Relationship of the Rum Industry to the Economies of P.R. and V.I..
Federal Excise and Domestic Taxes
Employment
Secondary Contribution
Economic Implications of Wastewater Treatment
Economic Model Plants
Effluent Treatment Cost Estimates
Required and Expected Price Increases
Impacts on Models' Viabilities
Other Impacts
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77
RELATIONSHIP OF THE RUM INDUSTRY TO THE ECONOMIES OF PUERTO RICO AND THE
VIRGIN ISLANDS
Federal Excise and Domestic Taxes
Tax revenues from Puerto Rican bottled and bulk rum are derived from two
basic sources. First, the U.S. Treasury returns $10.50 excise tax to the
Puerto Rico Department of the Treasury for every proof gallon of rum
produced there and shipped to the mainland. In 1977, this amounted to
$131.7 million and increased by 36.6$ to $179.9 million in 1978. Second,
local tax payments, including a $9.50 tax on each proof gallon sold in
Puerto Rico, amounted to $29.5 million in 1977 and $32.7 million in 1978.
Altogether tax revenues from the rum industry to the Treasury of Puerto
Rico amounted to $212.6 million in FY 1978. This is 12.7$ of the total
general fund receipts of $1,677.0 million and represents an increase from
11.1$ of general fund receipts in FY 1977.
This is summarized below for Puerto Rico for the past three years
(million $):
FY 1978 FY 1977 FY 1976
Taxes collected on rum $ 212.6 ~$~16^1.2 $~159.3
General fund revenues 1,677.0 1,455.9 1,327.1
Revenue from rum as percent
of general fund 12.7 11.1 12.0
A similar situation exists in the Virgin Islands. Federal excise taxes
on rum manufactured there are refunded to the Virgin Islands' treasury.
These revenues have increased by 37.1$ from $17.8 million in 1975 to $24.4
million in 1978. This amounted to 16.4$ of general fund receipts in 1978.
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Employment
Total direct employment in the rum industry in Puerto Rico in 1977 was
1,463 individuals. This included 769 employees working directly in
production and 694 employees involved in sales, management and other support
functions. Bacardi Corporation was the largest employer with 443 employees;
Destilleria Serralles had 433; and Puerto Rico Distillers employed a total
of 319 individuals.
The four major bottlers in Puerto Rico employed a total of 210
individuals. It is estimated that there are another 400 to 600 people
employed in support industries such as trucking, construction, lawn and
grounds, and special maintenance.
In the Virgin Islands, the total direct employment in the rum industry
is estimated at 100 individuals. It is estimated that from 20 to 50 more
are indirectly employed by the industry. Again this includes various groups
that contract with the two distilleries.
Altogether, these totals amount to about 0.3? of the total labor force
in both localities.
Secondary Contributions
The chief secondary contributions of the industry are its support of
Puerto Rican sugarcane and molasses production and bottle and carton
manufacturing.
Puerto Rico has historically been a net exporter of molasses. Economic
problems in the sugar cane industry have resulted in the island's becoming a
molasses importer in the 1970s. This trend will probably continue. The
Virgin Islands, also a historical producer of sugar, has become totally
dependent on imported molasses for its rum production.
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About 90% of the bottles used in Puerto Rico by the rum industry are
manufactured on the island by two companies. Sales to the rum industry
account for a significant portion of the bottle manufacturers' total
business. Small specialty bottles are generally imported.
Based upon the quantity of rum bottled in 1978, it is estimated that
from $13 million to $16 million is expended on bottles and cartons. This
provides a significant source of revenue to the bottle and paperboard
manufacturers. Further, it is estimated that from 300 to 350 persons are
employed in this segment of the industry.
Bottles and cartons used by the rum industry in the Virgin Islands are
imported from outside sources, including Puerto Rico. There is an
increasing trend in both localities, however, to ship bulk concentrated rum
to the U.S. mainland for bottling.
ECONOMIC IMPLICATIONS OF WASTEWATER TREATMENT
As discussed in Section 3, only five distillers (operating six plants)
presently remain in the U.S. Caribbean islands. In order to provide a
broader base from which to predict the economic implications of wastewater
treatment, a system of economic model plants was developed. These models
are representative of the more common financial and economic characteristics
of all existing distilleries.
A net present value (NPV) analysis was used to determine required price
increases necessary in the case of each of the nine models, under different
conditions, to offset treatment expenditures. These calculations,
considered with other economic characteristics of the industry, were used to
assess the ability of the industry to raise prices, likelihood of plant
closures, and possible losses of government revenues and employment.
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Economic Model Plants
Model plants were developed in three sizes (small, medium and large),
each with three levels of operational costs and profitability, yielding nine
model plants. Major assumptions are described below:
(1) The models were assumed to produce only rum.
(2) The models operated 250 days a year.
(3) As required by law, the models were assumed to age the rum at least the
minimum period of one year. The gold rum was assumed to be aged
approximately three years.
(U) The production processes were assumed to include distillation, aging,
and bottling. The bottling operations could be at the same or at a
separate facility.
(5) Since most distilleries age their rum for future bottling and,
accordingly, must produce in one year what they expect to sell in a
future year, it was assumed that the quantity of rum sold in a given
year would approximate 85% of that year's given production.
(6) The distillery models were assumed to be technologically modern
although the actual facilities, while they have been modernized over
the years, are fairly old and well depreciated.
(7) The models contained no provisions for major expansionary expenditures.
(8) As most existing distilleries have obtained exemptions from certain
taxes (which vary by distillery), the models were analyzed using two
tax scenarios—one with a tax rate of 25% and one with the standard 48$
tax rate.
Based on the preceding assumptions, the model plants' annual quantities
of rum produced were estimated to be as follows:
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Model Size Annual Product ion
(proof gallons)
Small 2,500,000
Medium 7,500,000
Large 17,500,000
Financial profiles of the models were developed to assess their
potential to deal with wastewater treatment expenditures. For these
profiles, model plant sales, costs, and investment characteristics were
developed from information provided by industry personnel and published
sources.
Effluent Treatment Cost Estimates
Costs for specific wastewater treatment options were not available for
this analysis. Thus, incremental treatment costs (capital) were utilized to
describe the point at which each model's impacts would be significant enough
to force closure. The cost increments varied according to model size, with
the small model's increments being in amounts of $500,000, the medium
model's increments being $1,000,000, and the large model's increments being
$2,000,000. Annual operating and maintenance expenditures associated with
each increment (capital) were assumed to be 10? of each investment increment
in one scenario and 20% in a second scenario. For each model's analysis a
total of twenty-five increments were considered.
Required and Expected,Price Increases
Required price increases differed with model size and treatment
investment increment. As expected, the small size models required the
greatest percentage increase and the large size, the least. The analysis
projected the increase that would be necessary under two conditions: that
the plants' partial tax exempt status continue and that the tax exemption be
removed.
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Again, as expected, greater price increases are required with an assumed
loss of tax exemption.
Economic input analyses indicated that price increases of 2% to &% would
be needed for most increments considered to maintain pre-control (treatment
of rum effluent) levels of profitability. If distilleries increase their
prices by 2% to 45E, the annual rate of sales increase (currently 9.6$) could
slow measurably for one or two years, but total sales would continue to
rise. After this time, the influences of income and population trends would
reestablish the market momentum of rum. If the required price increase were
5% to 8jt of its present price ($5.25 per proof gallon), the models' rates of
sales growth would slow considerably and, perhaps, even cease for one or two
years. After that period, however, the growth rate would begin to increase
again and, within three or four years, the industry would recover its
original rate of growth.
Considerable variation, however, could be expected in these projected
price increases because of economies of scale in treatment facilities.
Smaller distilleries will probably pay a higher per unit cost for control
than larger ones. For smaller distilleries price increases will then be
limited by the new market equilibrium price. This new market price will
effectively be established by the firm with the largest volume in the market
place. If this new price is lower than that required to meet the costs
incurred by the smaller distilleries, they will be forced to absorb the
remaining costs in their existing profit margin and/or reduce costs in other
areas, or to cease operations.
Impacts on Models' Viabilities
The extent to which effluent control costs—beyond those offset by
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83
increased prices—would impact production obviously depends upon the
interaction of complex variables. By applying closure criteria developed
for the study, it was possible to determine the highest treatment investment
increments (capital) and associated operation and maintenance (O&M)
expenditures the models could afford. These increments depended on the
models' size, operational efficiency level, tax exemption status, and
whether the treatment O&M expenditures were 10% or 20% of the applicable
treatment investment.
Table 11 depicts the largest investment increment affordable for the
model plants. As shown, the smallest affordable increments were associated
with the low efficiency models, particularly those analyzed under the
assumption of the standard ^Q% tax rates and the 20% O&M scenario. Under
these assumptions the low efficiency small model was projected to be able to
afford expenditures of approximately $500,000 or less, the medium model,
$1.0 million or less, and the large model, $2.0 million or less. For the
average efficiency models, the largest affordable increments were $4.5
million for the small model, $17.0 million for the medium model, and $40.0
million for the large model. Under less stringent assumptions, some average
efficiency models were projected to be able to afford all the investment
*
increments considered. For the high efficiency models, all investment
increments were projected to be affordable, except the small models which
were projected to be able to afford investment of up to $8.5 million.
•As stated previously, 25 increments of $500,000, $1 million, and $2 million
were considered for the small, medium, and large models respectively. Thus,
the maximum increment considered was $12.5 million for the small model,
$25.0 million for the medium model, and $50 million for the large model.
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84
Table 11. Largest possible capital investment for waste treatment with model plants remaining viable (no closure)
Model Ten$ O&M Scenario Twenty^ O&M Scenario
Type/Size Investment Increment Investment Increment
(million dollars) (million dollars)
Standard 48< Tax Bate
Average Efficiency
. Small 7.0 4.5
. Medium 23.0 17.0
. Large NC 40.0
High Efficiency
. Small 11.5 8.5
. Medium NC NC
. Large NC NC
Low Efficiency
. Small 1.0 0.5
. Medium 2.0 1.0
. Large 4.0 2.0
Modified 25$ Tax Rate
Average Efficiency
. Small
. Medium
. Large
High Efficiency
. Small
. Medium
. Large
Low Efficiency
. Small
. Medium
. Large
7.0
23.0
NC
11.5
NC
NC
2.5
7.0
16.0
5.0
17.0
40.0
8.5
NC
NC
1.5
4.0
8.0
NC: No closure at any of the investment increments considered.
Source: DPRA Economic Study
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Other Impacts
Whether or not government revenues would be impacted by the closure of
one or more of the presently operating rum plants would depend on whether
the market shares thereby lost were absorbed by another distillery. A
similar situation exists in relation to potential losses in the employment
sector and secondary impacts.
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REFERENCES
1. Development Planning & Research Associates, "Economic Impact of Effluent
Regulations on the Rum Industry (Puerto Rico and Virgin Islands)," 1979,
a report prepared for the U.S. EPA Office of Analysis and Evaluation,
hereafter cited as DPRA Economic Study. Unless otherwise noted,
material in this subsection, "Industry Structure," is based on
information contained in this document.
2. Internal communication with E.'J. Struzeski, Jr., U.S. EPA National
Enforcement Investigation Center (NEIC), Denver, CO., October 13, 1978.
3. The subsection "Process Description" is based on information in personal
communication from E.J. Struzeski, Jr., U.S. EPA NEIC, Denver, CO.
4. U.S. EPA Region IV, Surveillance and Analysis Division (SAD), "Rum
Industry Wastewater Characterization Study, Puerto Rico - Virgin
Islands, July, 1978" (1979). Unless otherwise noted, the subsection
"Wastewater Characterization" is based on information contained in this
document.
5. Stearns, Conrad & Schmidt Engineers, "Study of Rum Distillery Wastewater
Treatment and By-Product Recovery Technologies," 1979, a report prepared
for the U.S. EPA Office of Research & Development, hereafter cited as
SCS Technology Study.
6. SCS Technology Study. The subsection "Pollution Reduction through
Process Modifications" is based on Chapter IX of this document.
7. Erik Krabbe, U.S. EPA Region II Facilities Technology Division.
Testimony of Erik Krabbe for the adjudicatory hearing in the matter of
Puerto Rico Distillers, Inc., Schenley Industries, Inc., and Virgin
Island Rum Industries, Ltd., 1977.
8. Juan G. Gonzalez ^t al, "Biological Effects of Rum Slops in the Marine
Environment," 1979, a report prepared for the U.S. EPA ORD and the U.S.
Department of Energy, hereafter cited as Puerto Rico Report.
9. Michael J. Canoy ^t al, "Environmental Effects and Acceptability of Rum
Effluents," 1979, a report prepared for the U.S. EPA ORD, hereafter
cited as Virgin Islands Report.
10. Puerto Rico Report. Material in Section 4 relating to scientific
studies in Puerto Rico is based on information contained in this
document.
11. Virgin Islands Report. Material in Section 4 relating to scientific
studies in the Virgin Islands is based on information contained in this
document.
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87
12. Paul A. Friedman, Esq., White & Case, counsel for Seagram Company,
letter to E. Zell Steever, U.S. EPA ERL-N, December 29, 1978.
13. SCS Technology Study. Unless otherwise noted, Section 5 is based on
information contained in this document.
14. Dr. Douglas Conklin, University of California, Bodega Marine Laboratory,
and Dr. Michael Hartman, Savannah State College, Savannah, Georgia,
letters to Michael A. Caponigro, SCS Engineers, included in the SCS
Technology Study, Appendix A.
15. Dr. Norman H. Brooks and Dr. R.C.Y. Koh, California Institute of
Technology, correspondence referenced in the SCS Technology Study
throughout Chapter VI.
16. Internal communication with E.J. Struzeski, Jr., U.S. EPA NEIC,
Denver, CO., October 13, 1978.
17. DPRA Economic Study.
18. T.G. Shea £t al, Rum Distillery Slops Treatment by Anaerobic Contact
Process, a report prepared for the U.S. EPA ORD, 1974.
19. DPRA Economic Study. Section 6 is based on information contained in
this study.
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