yWATER POLLUTION CONTROL RESEARCH SERIES 1BI25-18000HIP07/71
INDUSTRIAL WASTE STUDY
MERCURY-USING INDUSTRIES
:NVIRONMENTAL PROTECTION AGENCY RESEARCH AND MONITORING
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INDUSTRIAL WASTE STUDY—
MERCURY-USING INDUSTRIES
By
Litton Systems, Inc.
Environmental Systems Division
3841 E. Santa Rosa Road
Camarillo, California 93010
for the
OFFICE OF WATER PROGRAMS
ENVIRONMENTAL PROTECTION AGENCY
Project #805/25-18000 HIP
Contract #68-Ol-OO61
July 1971
Environmental Protection Agency
Library, Region V
1 North Wacker Drive
,, Illinois. 60606.
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EPA Review Notice
This report has been reviewed by the Office of
Water Programs, EPA, and approved for publication.
Approval does not signify that the contents
necessarily reflect the views and policies of
the Environmental Protection Agency, nor does
mention of trade names or commercial products
constitute endorsement or recommendation for
use.
ENVIRONMENTAL PKOTECTIOfl AGENCY
11
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ABSTRACT
This study discusses information obtained from a literature survey,
mail survey, telephone contact phase, and field trip pertaining to
industrial wastes of mercury-using industries. The main topics
presented for each industrial group are: (1) uses of mercury;
(2) reasons for industry's use of mercury; (3) alternatives to use
of mercury in the industry; and (4) best available level of treat-
ment and control. Research needs are also recommended for future
studies.
In general, it was found that under present technology mercury
cannot be fully replaced in dentistry, the electrical industry
(lamps, batteries), production of chemicals (Pharmaceuticals,
laboratory reagents), catalysis, and industrial and control
instrumentation. Substitution is technologically possible but
probably not warranted because of minimal hazard from mercury use
in switches and in some industrial and control instrumentation.
Substitution is possible and highly desirable (in the absence of
fully effective treatment and control methods) in the chlor-alkali
and plastics industries. Use of mercury has come or is coming to
an end in agriculture, paints, and pulp and paper production.
The best present and proposed treatment and control methods can
reduce typical mercury concentrations in industrial waste waters
to levels of 1 to 5 ppb. However, very few facilities control
their mercury discharges to this extent.
This report was submitted in fulfillment of Project No. 805/25-
18000HIP, Contract No. 68-01-0061, under the sponsorship of the
Office of Water Programs, Environmental Protection Agency.
111
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ACKNOWLEDGMENTS
Numerous persons were instrumental in providing valuable
information for this study. In particular we wish to
acknowledge Messrs. Edmund J. Laubusch, The Chlorine
Institute; William Heifner, National Electrical Manufac-
turers Association; Robert Roland and Roy Brown, National
Paint, Varnish and Lacquer Association; Dr. Robert Shaver,
General Technologies Corporation; and Dr. T. C0 Ryker,
DuPont. Dr. E. A. Jenne, U. S0 Geological Survey, was
helpful in commenting on our information and report format„
The support of the project by the Office of Water Programs,
Environmental Protection Agency, and the help provided by
Messrs. Michael La Graff, Project Coordinator; Dennis
Cannon, Project Officer; and Larry Muir is acknowledged with
sincere thanks.
Mr. Donald M. Shilesky was the Project Manager and principal
investigator. Mr. Klaus W. Krause provided valuable assist-
ance and participated in the writing of this report.
IV
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CONTENTS
Section Page
I Introduction 1
II Mercury-Using Industries
Mining 3
Chemical Production 5
Agricultural Chemicals 12
Catalysts 13
Paint Industry 15
Pharmaceuticals 18
Pulp and Paper Industry 20
Chlor-Alkali Industry 22
Electrical Industry 29
Batteries 29
Lamps 30
Switches and Rectifiers 32
Industrial and Control Instrumentation 33
Dentistry 35
Laboratory and Hospital Uses 38
Mercury Reclamation 40
III Other Treatment and Control Methods
Chemical Production 41
Paint Industry 44
Treatment of Catalyst Wastes 44
Chlor-Alkali Industry 44
Switches and Rectifiers 49
General Treatment Methods 50
IV Research Needs 52
V Conclusions 54
VI Recommendations 58
VII References 60
Appendix A 65
Appendix B 72
v
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FIGURES
Figure Page
1 Flow Diagram of Mercury Mining 4
2 Waste Water Flow Diagram-Ventron Corp 8
3 Ventron Sodium Borohydride Process 9
4 Osaka Soda Mercury Recovery Process 11
5 Chlorine-Caustic Soda Flow Diagram—Mercury Cell.. 23
6 Brine Treatment Sludge Handling 25
7 Sodium Hydrosulfide Treatment Process 26
8 Mercury Recovery From Caustic Filter 28
9 Mercury Control in Production of English Vermilion. 41
10 Treatment of Chlor-Alkali Effluents 44
11 Process Flowsheet Showing the Hg Emissions
from a Mercury Cell 46
VI
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TABLES
Table Page
I Mercury Consumed in U.S. for Chemical Production.... 5
2 Summary of Best Available Treatment Methods for
Chemical Production 7
3 Summary of Other Treatment Methods by Industry 42
4 Summary of Other Treatment Methods by Treatment
Process 43
5 Summary of Best Available Treatment Methods for
Each Industry 55
Vll
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SECTION I
INTRODUCTION
Mercury contamination of the environment from industrial sources
is not a recent phenomenon. Beginning in the 1950's, Japan
experienced the effects of methyl mercury chloride pollution from
a vinyl chloride and acetaldehyde plant which was discharging into
Minamata Bay. The seafood taken from this bay was highly contami-
nated with mercury; and over a period of years, numerous persons
became ill and some died from consuming mercury-laden seafood. In
Europe, the Swedish government imposed a ban in 1968 on seed
dressings containing alkyl mercurials, following the discovery of
high mercury levels in wildlife; and it continues to conduct
detailed investigations of other industrial sources of mercury
contamination. Finally, in 1970 the attention of the world was
focused on the problem of mercury pollution when a Norwegian
graduate student at the University of Western Ontario, after
studying the pesticide problems that involve wildlife from 1967
.to 1970, reported high concentrations of mercury in fish from
Lake St. Clair.
The Federal Government has held extensive hearings, called
enforcement conferences, and begun litigation against several
companies for discharging mercury and its compounds into the
sewerage systems and watercourses of this country. Results of
these Government actions have been a notable reduction in mercury
discharges and industrial reassessment of the need to use mercury
and/or its compounds in production and manufacturing. At the same
time, a broad program of studies has been initiated to define the
environmental impact of mercury on air, water, and land. The scope
of the industrial aspects of the problem is suggested by the fact
that in 1970 industrial uses consumed over 4% million pounds of
mercury.
As a part of this Federal study program, this report defines the
state-of-the-art of the best level of treatment and control
currently available to the industries using mercury or its com-
pounds in production or processing. This study discusses by
industrial category the following topics:
1) mercury use
2) reason that the industry uses mercury
3) alternatives available to the industry instead of using
mercury
4) best level of treatment and control currently available
Furthermore, research needs are indicated when currently available
treatment and control technology is insufficient to meet effluent
criteria for mercury. The optimum effluent criterion is no dis-
charge. On the whole, significant and useful information is
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available on uses of mercury, reasons for these uses, alternatives
to these uses, and the nature of treatment and control methods;
but data on effectiveness of these methods (i.e., on the mercury
concentrations in final effluents) are relatively scarce.
To accomplish the objectives of this study, an in-depth litera-
ture survey was begun using Dow Chemical's extensive bibliography
on mercury. During this same period, 194 companies were contacted
by letter for information pertinent to this study, as were
numerous trade and manufacturer associations. A response of 46%
was received from the company survey, with one third of the
answers being "no longer use" or "do not use" mercury. Among
the industries no longer using mercury are electroplating,
jewelry casting, hat making, and explosives manufacture. Fifteen
associations answered a similar inquiry. Where the answers were
unclear or incomplete, telephone contact was made to acquire the
desired information. Further contacts were made with State and
Federal agencies to secure information. Following the literature
and mail surveys and telephone contact phase, a field trip was
made to visit companies using mercury in production and manufac-
turing, as well as to meet persons knowledgeable in the treatment
and control of industrial effluents containing mercury. After
the field trip, all information obtained was reviewed and
assimilated. Much of the information gathered by direct inquiry
from industrial sources is presented in this report without
reference to avoid individual company identification.
Finally, as a result of this investigation it has become clear to
the researchers that mercury is a widespread contaminant in many
commonly used industrial and household chemicals and products. In
this sense, very few people are not involved in a "mercury-using
industry" of some sort. The scope of the potential problem in
this situation requires definitive study.
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SECTION II
MERCURY-USING INDUSTRIES
Mining
Mercury is commonly found in nature, primarily as cinnabar (HgS);
but major ore deposits of economical quality are relatively few.
In the first quarter of 1971, 11 mines producing over 10O flasks
each (a flask contains 76 pounds of mercury) accounted for over
87% of U. S. production (1). (Figures for individual mines are
considered proprietary information.) Total U. S. mine production
in 1970 was 27,281 flasks (1), down slightly from 1969 and 1968
totals of 29,360 and 28,874 flasks, respectively (2).
In recent years, the average U. S. mine recovered approximately 5
pounds of mercury per ton of ore mined (2). The principal re-
covery method is by rotary kiln which heats the ore to as high as
1500°F. The mercury vaporizes and is collected by air-cooled
condensers. A detailed process diagram (Figure 1) is shown on the
following page.
The following treatment and control method is used at a major mer-
cury mine which was visited for this study. All the water required
in the processing of ore, such as that from a hoeing table and from
washdown of the mill floor, comes to a common drain which then
takes the water (5O gpm) through two counter-current traps. Then
the water is pumped to a tailings pond and allowed to pass through
the soil. When tested, mercury was undetectable in the water six
miles downstream of this tailings pond. However, the background
concentrations of Hg in the area are high. Ground water has a
mercury content of 8 ppb. Since geological characteristics of
mercury ore deposits are basically the same from area to area,
this information is probably applicable to mercury mining in
general.
Mercury has in the past been used also in gold mining to extract
finely divided gold from its ore. The mercury was amalgamated with
the gold, the amalgam physically separated from the ore, and the
mercury distilled off in retort furnaces to leave a gold residue.
This process was in use in recent years at only one mine and has
been completely replaced there by a cyanide process. The change
was prompted by high mercury levels in the mine's effluent streams.
Quantitative data are not available.
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Chemical Production
The production of industrial chemicals includes a large number of
organic and inorganic mercury compounds. In various forms and
formulations these chemicals become catalysts, finished products,
and raw and intermediate products for other industrial processes,
including the production of agricultural chemicals, paints, and
Pharmaceuticals. The production of mercurials, however, is basi-
cally a single category of industrial activity independent of the
diversity of end uses to which the products are put. Table 1
depicts the quantitative distribution of mercury consumed by
chemical production over the last five years.
TABLE I. MERCURY CONSUMED IN U.S. FOR CHEMICAL PRODUCTION (1,2)
(76-pound flasks)
Use 1966 1967 1968 1969 1970
Agriculture
Catalysts
Paint
Pharmaceuticals
2,374
1,932
8,42O
232
3,732
2,489
7,178
283
3,430
1,914
10,566
424
2,689
2,958
9,730
724
1,811
2,238
10,347
690
TOTAL 12,958 13,682 16,334 16,101 15,O86
1. Includes fungicides and bactericides for industrial purposes.
By definition, there are no alternatives to the use of mercury in
the production of mercury compounds as a whole. In specific in-
stances, of course, a non-mercurial may be a suitable substitute for
a mercury compound. For the producer of mercury compounds, however,
this may mean merely that production of the mercurial will end,
since he may not be equipped to produce the substitute. Specific
alternatives are applicable to end uses of the mercurials and are
discussed under individual uses in this section.
As a single industrial category, the production of industrial
chemicals, and specifically of mercurials, presents most of the
water pollution problems experienced in other mercury-using
industries. Reduced to its simplest terms, the basic problem is
to remove organic and inorganic, suspended and dissolved mercury
and mercury compounds in various initial concentrations from
effluents with a wide variety of characteristics. All aspects of
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this problem are represented to some extent in the treatment of
effluents from chemical production plants. It is useful, there-
fore, to consider at this point the best methods of treatment and
control applicable to this industry, and to discuss variations and
exceptions in these methods where applicable under the specific
industrial activities involved.
Best Available Level of Treatment and Control for Chemical Production
In general, treatment and control techniques for mercury in liquid
wastes consist of chemical reactions and physical separation
methods. Among the chemical means are conversion (e.g., organic
to inorganic compounds), chelation, ion exchange, and precipita-
tion; the physical means consist of filtration, centrifugal separa-
tion, and gravitational settling. The chemical means are generally
applicable to dissolved compounds and the physical means to suspended
particles. Surface-chemical effects can also be used to remove
mercury from waste streams, with flocculation being effective for
suspended solids and activated adsorption for dissolved solids.
Various combinations of these individual techniques can be used to
provide the best available treatment methods for characteristic
effluents of different mercury-using industries. Table 2 sum-
marizes the four best available treatment methods and their appli-
cability and effectiveness.
Sodium Borohydride and Chelating Resin Treatment Process
This method of treatment and control of mercury in chemical pro-
duction effluents is a recently developed process in limited
field use and is based on mercury reduction with sodium borohydride.
Figure 2 is a diagram of the waste water flow from the production
of mercurial and non-mercurial chemicals. Description of the
"mercury removal process" indicated in Figure 2 is depicted in
detail in Figure 3. This removal process is the primary treatment
system used by its developer, the Ventron Corporation.
Mercury-bearing waste waters resulting from production of purified
mercury and mercury-based chemicals are treated to limit mercury
discharges to an average of less than O.5 Ibs/day (three shifts) in
aqueous effluent. Since the plant effluent flow rate varies be-
tween 15,OOO and 4O,OOO gpd, the effluent contains mercury in the
range of 1.5 to 4 ppm (mg/1). Before mercury removal in the primary
treating system, the processing discharge from production of in-
organic compounds contains 5O to 150 ppm mercury, and that from
production of phenyl organic compounds contains 10 to 80 ppm (after
chemical pre-treatment).
The primary treatment method involves a proprietary combination
of chemical conversion of organic to inorganic mercury compounds,
precipitation with sodium borohydride, and physical separation. The
effluent from the primary treatment process is secondarily passed
through a chelating resin bed for further reduction of mercury
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content. Use of the chelating resin as a secondary treatment pro-
cess is still under investigation by Ventron. Ultimately, the
Ventron Corporation expects to achieve mercury levels of 1 to 5 ppb
by combining sodium borohydride reduction with secondary treatment
of a chelating ion exchange resin.
Osaka Soda Mercury Recovery Process
The Osaka Soda (OS) Process, as seen in Figure 4, was developed
over a ten-year period in Japan and has been used commercially in
four Japanese chlor-alkali plants for up to five years. It is
also claimed to be applicable to waste streams from pulp and
paper, electrical, instrument, chemical, and pharmaceutical in-
dustries (4).
Solutions are treated by adjusting to a free chlorine content and
then filtering. At this point, the Hg concentration has been
reduced from an initial value of about 2O ppm to about 5-7 ppm (5).
The filtrate is then passed over ion exchange resin (reducing
mercury level to about 150 ppb (5)) and then through a tower con-
taining Osaka Soda's MR resin. The MR resin reduces mercury content
to a typical level of 2 ppb and a maximum level of 5 ppb. Mercury
is then recovered from the primary ion exchange resin; the MR
resin is discarded several times a year (4).
Cationic Polymer Flocculation
Another treatment process has been developed to keep the effluent
concentration of mercury down to the concentrations of 2.5 ppb to
15 ppb by employing a cationic polymer for flocculation of the
waste water effluent stream containing mercury. The flocculant
removes approximately 99% suspended solids and 60% of the chemical
oxygen demand (COD) from the waste stream. In addition, approxi-
mately 95% of the phenyl mercurials are removed from the waste
by this flocculant step so as to produce a treated effluent stream
appreciably devoid of mercury, suspended solids, and COD (6).
This process is presently being used in treating a paint manu-
facturer's effluents.
Proprietary Process—Terraneers, Limited
Terraneers, Limited has developed a mercury-removal system which
brings waste waters down to levels of 1O ppb. The exact nature
of the process has not been revealed to date because of patent
considerations. The waste has to be neutralized (pH 8), dechlori-
nated, and filtered prior to reprocessing in this system (7).
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Agricultural Chemicals
Accurate figures for the consumption of mercury for agricultural
chemicals are not available, since the standard Bureau of Mines
statistics include fungicides and bactericides used for indus-
trial purposes under the Agriculture use category. With this
qualification, agricultural consumption of mercury in 1970
amounted to 1811 flasks, a significant reduction from an average
level of about 3OOO flasks in previous years (1,2)0 This reduction
can be fairly confidently attributed to the Department of
Agriculture's cancellation of registrations of alkyl mercurials,
which did not become officially binding until late in the year
but which clearly indicated the limited future in mercury
pesticides. The first quarter of 1971 shows the use of 338
flasks, up from ISO in the last quarter of 1970. Quarterly
figures for the past two years, however, show similarly large
fluctuations (8), so that no special significance can be attached
to this statistic.
Alternatives to the mercurial pesticides have long been avail-
able but have been little used because they have drawbacks in
terms of cost, effectiveness, or ease of application. The
cancellation of registration for alkyl mercury pesticides,
however, is forcing the adoption of existing substitutes and
the development of new ones. Major producers have already dis-
continued lines of agricultural mercurials and are marketing
substitute products.
Specifically, non-mercurial fungicides being produced for small
grains include thiram, maneb, and captan. For cottonseed, the
same three are available, as well as Terracoat L21, Busan 72,
and chlorothalonil-Dexon. Use of a systemic fungicide like
chloroneb or carboxin in conjunction with one of the others has
resulted in. levels of effectiveness equal to or greater than
those of mercurials (9). These combinations and others tend to
approach the broad spectrum of activity of the mercurials, which
none of the substitute products individually possess (1O).
Chemical compositions and other data on specific products are
presented in Appendix A.
Since agricultural chemicals are generally marketed directly
by the chemical producers, the treatment methods described
on pages 6-10 are directly applicable.
12
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Catalysts
According to Bureau of Mines reports (1,2), the yearly average of
mercury consumption in catalytic use was 2,300 flasks for the
period of 1966 to 1970. No appreciable trend in increased or
decreased consumption is evident during this period.
Mercury catalysts have been tried as esterification, hydration,
reduction, oxidation, dehydration, chlorination, fluoridation,
sulfurization, sulfonation, isomerization, polymerization, and
disproportionation catalysts.
The important mercury compounds that are used industrially or
experimentally as catalysts are:
Mercury Mercuric oxide
Mercuric acetate Mercuric phosphate
Mercuric chloride Mercuric sulfate
These compounds have been used extensively in the manufacturing
of acetaldehyde, vinyl acetate, vinyl chloride (plastics), and
sulfonated anthraquinone (vat dyes) (11). Information on the
relative quantities of these different mercury catalysts used
was not found.
Organic mercurial salts are used in urethane elastomers for
casting, sheeting, and sealant applications. Another use of
organic mercury catalysts is in a urethane resin, molded into
a nearly indestructible automobile bumper. Approximately three
parts of commercial mercury catalyst are employed in each 1OO
parts of resin. Active content of mercury in the catalyst is
about 5%o A low-cost sealant, whose production is in the multi-
million pound range, also employs PMA (phenyl mercuric acetate)
catalyst. In this case, about 0.1 per cent of the PMA dissolved
in a solvent is used for each 100 parts of resin. Active content
of mercury in the catalyst is again 5 percent. Cellulosic
sheeting is backed by these kinds of urethane elastomers and is
the subject of U. So and foreign patents (12).
Vinyl chloride (CH2=CHC1) monomer is produced by the reaction of
HCl with acetylene in the presence of a catalyst, mercuric
chloride. About 0.074 pound of mercury used as a mercuric
chloride catalyst is consumed per thousand pounds of vinyl
chloride monomer in the acetylene process (12). Further data
describing the percentage of consumed mercury that would be
released in waste water were not available.
13
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All mono- and disulfonic acids (except the 2-anthraquinone sulfonic
acid) of anthraquinone require use of a mercury-salt catalyst for
sulfonation (11)0 These acids are produced by the sulfonation of
anthraquinone with oleum, the orientation of the entering group
being determined by whether or not mercury is used as a catalyst
(13).
Another catalytic use of mercury is the process of making acetalde-
hyde by hydration of acetylene. Vinyl acetate, also, is made by
the condensation of polyhydric alcohols, with mercuric chloride
catalyzing this reaction.
Vinyl chloride monomer production (used in plastics) is shifting
from the requirement of acetylene plus mercurial catalyst to
oxychlorination of ethylene to make ethylene chloride, which is
subsequently cracked to vinyl chloride (11). Substitutes for
organic mercurial salts used in production of urethane elastomers
are amines and stannous soap and salts (12). Dehydrogenation and
air oxidation of ethyl alcohol are production methods now being
used to manufacture large quantities of acetaldehyde (11).
Effluents from catalytic reactions can be treated by the methods
described on pp0 6-10 to remove mercury and both organic and
inorganic mercury compounds.
14
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Paint Industry
The principal use of paint in general is for protection of
surfaces from environmental exposure. Many categories of paint
compose this industry's product market. The two basic types
used are solvent-thinned and water-thinned (latex) paints.
Special antifouling paints are applicable to protection of
underwater marine surfaces. The principal use of mercury in
paints is as a can preservative and mildewcide (fungicide) for
latex paints and as a mildewcide in many solvent-thinned paints.
Phenyl mercury compounds are the most widely used additives.
Depending on the climate, 3.5 to 10 pounds of phenyl mercuric
acetate (PMA), which is 18% mercury by weight, are required per
hundred gallons of both types of paint for effective protection
(14). In 1970, 10,149 flasks of mercury were used in the formu-
lation of mildew-proofing (fungicide) and preservative compounds
for paints (1). Previously, an average of 8,63O flasks/yr were
consumed for these purposes in the years 1965 - 1969 (2). By
contrast, for the last five years, the use of mercurials in anti-
fouling paints has been kept to a minimum, ranging from a con-
sumption of 140 flasks in 1966 to a high of 392 flasks in 1968 (2).
In 197O, 198 flasks were required to produce antifouling compounds
in paints (1). It must be realized that, generally, the paint
companies do not manufacture mildewcides or antifoulants but
purchase these compounds as additives to their paint products.
Phenyl mercurials are a general protoplasmic poison when they
come in contact with molds, mildew, and bacteria. Phenyl
mercurials prevent the growth of mildew on exterior paint systems
applied over bare wood through long-term protection of the wood
surface. Fungicidal mercury compounds are securely bound,
in an undetermined manner, in the wood surface beneath the paint
film (15).
Alternatives to the Use of Mercury
Cuprous oxide and tributyltin oxide have already generally
replaced mercuric oxide in antifouling paints, although mercuric
oxide is still registered for use under the Federal Insecticide,
Fungicide, and Rodenticide Act.
A recently published list (16) of paint biocides (including phenyl
mercurials) contains a number of possible substitutes for mer-
curials. Among the apparently most widely applicable are modified
barium metaborate, parachlorometacresol, dodecylguanidines,
thiocyanates, chlorophenols, and salicylanilides. All of these
are suggested by the manufacturer as candidates for use as
fungicides and preservatives in both solvent-thinned and water-
emulsion paints. The complete list appears in Appendix A.
15
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However, toxicities of these compounds have not been completely
determined, nor have their fungicidal or bactericidal qualities
been finalized. These products are presently being evaluated
by their manufacturers and by paint companies, and further
definitive research and long-term evaluation are clearly needed
to assess the suitability, effectiveness, and safety of these
and other potential substitutes for mercurials in paints. The
paint industry has estimated that two years of research will be
required for discovery and testing of substitutes as fungicides on
exterior surfaces (17).
Best Available Level of Treatment and Control
The best available method of control presently used for latex
paint production is the retention and subsequent recycling of
wash water into a new batch of paint. This process also is
applicable to solvent-thinned paint production in that the solvent
sludge from vat cleaning can be similarly reused,, Therefore,
the best level of control exercised is the ideal one of no dis-
charge. * The cleanup procedure after manufacturing a batch of
paint is to scrub the mixer and wash down with water or solvent
for latex or solvent-thinned paint, respectively. This wash
water or solvent, which may contain fungicide and preservative,
is then pumped into a holding or storage tank. The water or
solvent stays in the tank until it can be pumped back into a
new batch mix. However, the closed recycling system is not
applicable to all paint manufacturers. The smaller production
facilities cannot afford this system, and they do not always
have the available space for the storage tanks which are required.
The reason for a number of storage tanks is that each type of
paint is of a specific formulation and contains different ingredi-
ents; therefore, the blending of the retained wash water or
solvent sludge must be matched and must not interfere with the
ingredients in the new batch being manufactured.
This process of holding the wash water or solvent sludge has
further complications in that the size of the manufactured
batch, and consequently the entire process, varies at each
company. The recirculation ratio of hold wash water or solvent
sludge to new make-up ingredients also varies from company to
company. Furthermore, the mercury content of the wash water
or sludge is dependent on the type of paint being produced and
the amount of mercury additive used.
Solvent-thinned paint wastes can be settled and filtered and
the waste solids incinerated. No water pollution results from
this process since the solvent is not discharged into a water-
course or sewage system. Some paint companies incinerate this
type of waste on their premises. Others send their wastes to
a separate company whose business is to dispose of industrial
16
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wastes. The solvent-thinned paint wastes are then incinerated
on the waste disposal company's premises (18).
Paint companies not employing these methods of treatment and
control can use those methods described under Chemical
Production, pp. 6-10.
17
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Pharmaceuticals
According to Bureau of Mines statistics (1), 690 flasks of mercury
were consumed by the pharmaceutical industry in 197O. This
level of usage indicates an apparent return to a downward trend
in mercury consumption for Pharmaceuticals evident between
1950 (5996 flasks) and 1966 (232 flasks), after a three-year
upswing to 724 flasks in 1969 (2,8).
Mercurials are used in a number of pharmaceutical and cosmetic
preparations. Organic mercury compounds are used in diuretics
and antiseptics; inorganic mercury salts are used in solutions
for sterilization of instruments; ammoniated mercury, oxides
of mercury, and metallic mercury are used in skin preparations;
phenyl mercury compounds are used as preservatives in cosmetics
and soaps (12).
For all uses except diuretics, the antimicrobial properties of
mercurials are the essential reasons for the use of these
compounds in pharmaceuticals, cosmetics, and soaps. "The
inactivation of bacteria by mercurials may be caused by a
blocking of cellular enzymatic thiol receptors with formation
of mercaptide bonds, and without any other demonstrable cell
injury" (19). Another suggestion is that the mercurial interferes
with essential sulfhydryl groups of organisms (20).
Effective nonmercurials are available for use as diuretics, and
substitutions are possible in antiseptics, sterilization
solutions, skin preparations, and preservatives (12). Hexachloro-
phene, for example, is a nonmercurial disinfectant and is
commonly used in germicidal soaps (21). It is also used in the
treatment of burns (although mercurochrome appears to promote
more rapid healing) (22). Bithionol compounds are nonmercurials
effective as topical antiseptics (21). Iodine and iodine compounds
are, of course, also still widely used as nonmercurial antiseptics.
Thiazide compounds (e.g., benzthiazide, chlorothiazide) and other
nonmercurials (e.g., chlorazanil, acetazolamide, theobromine) are
already reducing the importance of mercurials as diuretics (11,21).
One general factor in opposition to development of nonmercurial
substitute Pharmaceuticals is the need for recertification by
the FDA. Aside from the costs of development and testing, there
is a significant time lag in the processing of new drug applications.
Best Available Level of Treatment and Control
Limited information was obtained on the treatment and control methods
used by pharmaceutical manufacturers using mercury and its compounds.
Information obtained indicates that the amount of mercury-containing
18
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residues resulting from the production of certain pharmaceuticals
is 0.1% of the quantity of mercury used in the end product. For
example, if 1O mg of phenyl mercuric acetate (PMA) is used as a
preservative in a tube of topical cream, O.O1 mg of PMA per tube
would be the residue resulting from the production of this
pharmaceutical. These mercury-containing residues are discarded
by a State-approved system of dry-fill burial, with no residues
discharged into or reaching any stream. Insufficient information
is available to rule out the possibility of groundwater contamin-
ation, however,
In general, the treatment methods described on pp. 6-1O
are applicable to effluents contaminated by pharmaceutical
mercury compounds.
19
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Pulp And Paper Industry
Mercurial compounds (mostly phenyl mercuries) played an important
part for many years in slime control applications in the pulp
and paper industry. Their use, however, had been steadily de-
clining even before the mercury controversy of 1970, which
resulted in their complete discontinuance (23). This trend is
evident in Bureau of Mines consumption figures (1,8), which
show an almost uninterrupted decline in usage from 3,481 flasks
in 1960 to 226 flasks in 1970 (most of which were used in the
first quarter). Consumption for the first quarter of 1971 has
dropped to zero (1).
As in agricultural, paint, and pharmaceutical uses, the biocidal
properties of mercurials made them useful compounds in pulping
and paper manufacturing processes. They are effective over a
broad pH range and against a wide variety of microorganisms (23).
Alternatives to the Use of Mercury
The pulp and paper industry now uses only nonmercurials for
slime control. In general, however, these alternative products
are more specialized either in pH range or in microorganism
activity. By using products in proper combinations, however,
the effectiveness of the mercurials should be attainable (23).
Four main areas of application can be defined, with particular
products most suitable to each area (23):
1. Bacteria control at pH's below 7.O. Methylene bisthio-
cyanate-based products are the most common in this area, and
they include Nalcon 270, 271, 272 and 273 and Betz's Slime-Trol
Rx 30, Rx 31, Rx 32 and Rx 38. In some instances, better
performance .can be obtained with an organo-sulfur by itself
or alternated with a methylene bisthiocyanate product. Examples
of these cases are where pink slime is a potential problem or
where the aerobic, nonsporeforming bacteria Pseudomonas is the
chief cause of trouble. Such organo-sulfurs include Nalcon 243,
244 and 246.
2. Fungi Control. The chlorinated phenols are the usual alter-
nates in this area, although the amines are good also. Some
examples in the chlorinated phenol category are Nalco 21-M,
Nalco 21-S and Nalco 201 and Betz Rx 12, 17, 23 and 26. Nalco
236 is a popular amine-based material.
3. Bacteria Control at pH's above 7.0. The organo-sulfurs and
the amines are most favored in this area, while methylene bis-
thiocyanate products can be used with special feeding techniques.
20
-------
4. Preservatives. In general, the organo-sulfurs and chlor-
inated phenols have shown the best performance and are covered
in the Betz-Nalco range. The organo-sulfur is generally pre-
ferred because of its broad pH range and FDA clearance for
coatings applications„
Of the various organo-sulfurs available, apart from the above
products, R. T. Vanderbilt's Vancide 51Z has proved effective
as a mold-proofing agent, preservative and slimicide. It is
a compound of zinc dimethyldithiocarbamate (87 per cent), zinc
2-mercaptobenzothiazole (7.5 per cent) and having total zinc
as a metallic of 19.8 per cent. As far as mold-proofing is
concerned, it is as effective as mercury. For mold resistance
in some applications requiring FDA clearance, Vancide P-75 has
also proved effective. Its composition: N-trichloromethyl-
mercapto-4-cyclohexene-l 2-dicarboximide (75 per cent) and
inert ingredients 25 per cent (23).
Best Available Level of Treatment and Control
Although mercury is no longer being used in the pulp and paper
industry, it still appears to be a possible heavy metal in the
plants' effluent streams (24). The explanation of this pheno-
menon is that the caustic soda (produced by mercury cells) used
in processing the pulp and paper contains a certain amount of
mercury contamination. Since this industry uses considerable
amounts of chlorine and caustic, mercury contamination would be
very possible. The manufacturing processes where this contam-
ination would appear are:
Kraft Bleaching: Semi-Bleach
High Bleach
Dissolving Grades (Soft Wood)
Dissolving Grades (Hard Wood)
Sulfite Pulp Bleaching: Paper Grade
Dissolving Grade
If mercury-free caustic and chlorine cannot be obtained for
pulp and paper processing, the industry may have to adopt one
or more of the treatment methods described on pp. 6-10 to
eliminate mercury discharges entirely.
21
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Chlor-Alkali Industry
Production of chlorine and alkali is one of the largest indus-
trial consumers of mercury in the United States. According to
Bureau of Mines reports, 15,011 flasks of mercury were used in
1970 for the electrolytic preparation of chlorine and alkali
(1). Previously, 2O,720 flasks were consumed for production in
1969 and 17,453 flasks in 1968 (1,2). However, prior to 1968
the production use of mercury averaged 11,533 flasks for 1965
to 1968 (2). Reasons for the 27% decrease in mercury consump-
tion from 1969 to 1970 were economic conditions in the country,
and the strict control measures imposed by the government on
the discharge of mercury to the environment.
Mercury has a unique combination of properties enabling it to
be liquid, electrically conducting, and chemically amalgamative
during the production of chlorine and caustic. In the mercury
cell method, mercury is used as a flowing cathode for the
electrolysis of sodium chloride. Chloride ion is oxidized at
the anode to form a fluid sodium amalgam. Amalgamation serves
to transport the reduced sodium from the electrolytic reaction
to the caustic-producing regeneration compartment, where it is
catalytically reacted with water to form caustic soda and
hydrogen. Mercury is then recycled to the electrolyzer section
(25). This entire process is depicted in Figure 5. Appendix
B contains another diagram of the process, showing in detail
the points of mercury discharge.
Alternatives to the Use of Mercury
Alternatives to the use of the mercury cell for chlor-alkali
production are the diaphragm cell and the Downs cell. The
diaphragm cell is used by 54% of the chlor-alkali manufacturers,
as compared to 4O% of the manufacturers operating a mercury
cell and 6% operating a Downs cell.
In a diaphragm cell, the electrolytic reaction products are
kept separate by an asbestos diaphragm. When an electric
current is applied to a salt solution within the cell, chlorine
is generated at the positively charged anode on one side of
the diaphragm. Meanwhile, the negatively charged cathode on
the other side of the barrier attracts dissolved sodium ions,
ultimately producing caustic soda and hydrogen gas (26).
The Downs cell involves an electrolytic process which takes
place in a closed, rectangular, refractory lined steel box.
The anode is made of carbon and the cathode of iron. Anode
and cathode are arranged in separate compartments to facilitate
22
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the recovery of the sodium and chlorine. The electrolyte is a
eutectic of 33.2% sodium chloride and 66.8% calcium chloride.
The relatively low operating temperature increases the life of
the refractory lining of the cell, makes it easier to collect
the chlorine, and prevents the sodium from forming a difficultly
recoverable fog (27).
However, the Downs cell and the diaphragm cell do not produce
caustic soda which is sufficiently pure for many important
applications. Mercury-cell-grade caustic is the preferred
material for most applications when available at the equivalent
price of diaphragm-cell caustic. The Chlorine Institute states
that the diaphragm-cell caustic, no matter how it might be
later purified, is still technically inferior in meeting the
needs of the rayon, cellophane, and pulp and paper industries
as well as being unsatisfactory as food stock for a number of
specialty chemicals (28).
Best Available Level of Treatment and Control
Mercury is emitted from three main areas during the manufac-
turing of caustic and chlorine. They are: 1) the hydrogen
stream, 2) the brine mixtures leaving the cell, and 3) the
suspended elemental mercury in the product alkali (7,19). The
concern in this study is the liquid mercury and mercury compounds
leaving with the process waste waters from the brine treatment
sludge handling (see Figure 6) and the suspended elemental
mercury in the product alkali.
Plant Waste Water Treatment
Currently, the best treatment method of these process waste
waters is a combination of precipitation with sodium hydro-
sulfide (NaHS) or ferrous chloride (FeCl ), and the employment
of activated carbon as a cleanup bed, the precipitate being
collected as solid waste. A treatment scheme employing NaHS
is shown in Figure 7.
Activated carbon, as shown in Figure 7, is a secondary treatment
process following the precipitation by NaHS. The concentration
of Hg in the effluents from the precipitation process is
approximately 1OO ppb. Employment of the activated carbon as
a cleanup bed results in mercury levels of 10-20 ppb (7). The
efficiency of this mercury removal process is about 99.7% since
the mercury is reduced from approximately 40 lb/100 tons Cl
produced to a range of O.O5 to 0.25 Ib Hg/lOO tons (25).
Caustic Purification Treatment
Further treatment of the caustic end product can generally be
recommended since the caustic will normally contain up to 10 ppm
mercury. This mercury content can be reduced to 1 ppm with
24
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filtering without precoat, and to 0.05 ppm with use of precoat
(preliminary application of certain substances to filter material
to improve filtering capabilities). Both cellulose and carbon
are used for precoat, with the performance of the carbon better
than that of the cellulose. The sludge from this filtration is
agitated, settled, and decanted, whereupon 85% of the contained
sludge is recovered as metallic mercury. The remaining sludge
is subjected to secondary filtration, and the filtrate is
returned into the product stream. Recovery of mercury from
this secondary sludge can be achieved via distillation or retort-
ing. This entire process of mercury recovery from caustic filter
is shown in Figure 8 (7).
Other best levels of treatment applicable to chlor-alkali produc-
tion are discussed under Chemical Production, pp0 6-10.
27
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28
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Electrical Industry
Battery, lamp, switch, and rectifier manufacturers comprise the
categories of mercury-using companies in the electrical field.
According to Bureau of Mines reports (1,2), 15,952 flasks of
mercury were consumed in 1970 for electrical apparatuses.
Previously, 18,65O flasks were used for production in 1969 and
17,484 flasks in 1968. A level of consumption above 14,50O
flasks of mercury was maintained through the years 1965 to 1967.
The following discussion is divided into sections on batteries,
lamps, and switches and rectifiers.
Batteries
Mercury cells are used in lighting devices, photographic equip-
ment, medical electronic equipment, transistor radios and other
transistorized devices, missiles and satellites, instruments
and computers, and clocks and watches (3O). For example, mercury
batteries are used in 75 to 8O per cent of all hearing aids.
They are also used for high-demand, high-reliability applications
such as power sources for sono-buoys, marine devices, and air-
sea rescue radios and beacons.
The major advantage of mercury cells over other batteries is
their small size. Mercury batteries deliver the same electrical
energy in cells one-third to one-fourth as large as comparable
zinc-carbon batteries (14). They also have a longer shelf life.
Furthermore, they lose less voltage with either steady or inter-
mittent use; other batteries start to fade appreciably after only
partial use (31). Mercury is used in both the mercury cell and
the alkaline energy cell, where it is amalgamated with zinc to
reduce hydrogen over-voltage at the anode (12). In the mercury
cell, the positive electrode also includes mercury as a mixture
of graphite and mercuric oxide. In this cell, the anode and
cathode are separated by a composite shield that contains an
electrolyte of potassium hydroxide and zinc oxide (11).
The determination of alternatives to mercury batteries concerns
three types of batteries. Two of these alternative batteries
(magnesium-alkaline and zinc-carbon) have a small quantity of
mercury used in their manufacture. The third battery, nickel-
cadmium, does not require mercury and is rechargeable. Size of
the battery and rate of energy drain from the battery are impor-
tant parameters in the selection of the proper battery for a
given use.
Mercury batteries generally have an energy density of 45 watt-
hours/lb, while zinc-carbon batteries have a range of 10 to 67
watt-hours/lb with an average density of 15 watt-hours/lb.
29
-------
Therefore it would take about three average zinc-carbon batteries
to replace an average mercury battery. Five nickel-cadmium
batteries would be required to replace the average mercury
battery, since the energy density of nickel-cadmium batteries
ranges from 4 to 2O watt-hours/lb, with an average battery being
rated at 1O watt-hours/lb (32).
Best Available Level of Treatment and Control
Two types of battery manufacturing processes affect the best
level of treatment and control. In one process, where virgin
mercury is chemically compounded into a dough-like material and
extruded into battery casings, there is no discharge of mercury
in the effluent. However, in the second process, the use of
process water in the production of mercuric oxide and zinc
amalgam creates two points of discharge into plant effluent (33,34)
The treatment for soluble mercury in mercuric oxide production
is to adjust the pH to 7, add sodium sulfite, and allow the
mercury to precipitate out of solution as an insoluble compound.
Mercury concentration in this effluent is less than 2.5 ppm.
Treatment method for the mercury in the zinc amalgam production
is to weir out heavy particles through several holding sections
and treat with scrap zinc. This zinc is periodically changed
as the mercury is amalgamated with the zinc. The concentration
of mercury in this effluent is less than O.5 ppm. For further
reduction of mercury content, the methods described on pp. 6-1O
could be used (33).
Lamps
Mercury is used as a basic or supplementary light source in most
types of gas discharge (as opposed to incandescent) lamps. In
the common fluorescent tube, mercury is vaporized by an electri-
cal discharge and excited to emit ultraviolet radiation, which
in turn stimulates the emission of visible light from phosphors
coating the inside of the tube. In the high-pressure mercury
lamp, mercury vapor at a pressure of about two atmospheres emits
visible light directly, without an intermediate phosphor stage.
Mercury lamps are also produced with various additives (metals
and metal halides) for improved electrical and/or color charac-
teristics (35).
Compared to other industrial uses, the lighting industry uses
only a minute portion of the over 6 million pounds of mercury
used in the United States in 1969. It is estimated that about
48,000 pounds of mercury were used in the manufacture of 6.2
million mercury and metal halide lamps and 268.2 million fluor-
escent lamps by the lighting industry in 1969. This usage
accounts for only about O08% of the 6 million pounds total
30
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mercury used and 3.5% of the 1.382 million pounds used in elec-
trical apparatus (36). In addition, lamp production involves
no use of process waters which could result in mercury-contam-
inated plant effluents.
The relatively low amount of mercury used by the lighting industry
for making lamps is due to the small amount of mercury required
in each lamp. For example 5O milligrams (mg) or O.OOO11 pounds
of mercury are used to manufacture a standard 4O watt fluorescent
lamp, 68 milligrams for a 4OO watt mercury lamp and 51 milligrams
for a 400 watt metal halide lamp (36).
Mercury lamps are used extensively for street and highway lighting,
in high-ceilinged rooms, and where intensive lighting is needed
for motion picture projection, in photography, for examination of
teeth, in heat lamps, and for water sterilization (11).
Mercury is used in the manufacture of high-intensity discharge
lamps (mercury, metal-halide, and sodium-mercury lamps) and
fluorescent lamps because it has the unique physical and electri-
cal properties responsible for the high energy conversion
efficiencies of these light sources. These lamps deliver more
lumens per watt of energy consumed than any other commercial light
source. Incandescent tungsten lamps and some noble gas (neon and
helium) lamps could be alternatives to using mercury lamps, but
they are low in efficiency and therefore require greater amounts
of power. Total conversion to low-efficiency lighting would
require more electrical power than the present generating
capacity of the power industry.
Best Available Level of Treatment and Control
Since no process discharges take place, routine precautions in
handling and storing of mercury apply. Mercury is received in
flasks. For use, it is placed in dispensers and sealed. A
hypodermic-type needle is then used to inject a single drop of
mercury into each lamp. Control is further exercised by having
sumps under floor drains to contain any spilled mercury. These
sumps are periodically cleaned. Mercury vacuum cleaners, equipped
with dust and charcoal filters, are used to clean the manufacturing
area (37).
Mercury flow diagrams of two fluorescent lamp plants and one
high-intensity lamp plant are shown in Appendix B. Losses of
mercury (1% to 6%) are indicated in these diagrams., These losses
may be attributed to evaporation.
31
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Switches and Rectifiers
Power rectifiers account for most of the mercury used in electron
tubes. Mercury is also used in producing silent, smooth, friction-
less, and durable switches, for which it provides a self-replen-
ishing contact material. The mercury provides a low contact
resistance with very stable repeatability from operation to
operation, as well as over long life of billions of operations (12).
Mercury rectifiers have to a large extent been replaced by silicon
and/or selenium rectifiers. For many applications, alternatives
are also available to substitute for mercury switches, but they
are not as reliable or economical. Mechanical switches,'.for
example, will serve as well as mercury switches in many cases, but
they are much less durable under heavy use. Solid-state switches,
such as those based on bi-metallic thermostatic elements or on
capacitive effects (touch-plate switches), are also potential re-
placements for mercury switches (12).
Best Available Level of Treatment and Control
No treatment is required in the manufacturing of mercury switches
and rectifiers. Mercury does not enter any waste water streams
in the manufacturing plant. Therefore, control consists of
precautions in the handling and storage of mercury to avoid
accidental discharges. One procedure in use involves storage of
mercury in sealed plastic bottles. The mercury is withdrawn
from the bottles by a vacuum system and inserted into switch
capsules by a pressure system. All mercury-contaminated scrap
is transported in closed plastic containers to be refined for
mercury salvage by a vendor (38).
32
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Industrial and Control Instrumentation
Mercury is used as an indicator in instrumentation because of its
liquid state at normal temperatures, because of its stable physi-
cal characteristics, and because of its uniform responsiveness to
changes in environmental parameters. The items in the following
list of control apparatuses and instrumentation all commonly use
a certain amount of virgin mercury in their operation (11).
Thermometers Vacuum gauges
Hygrometers (measurement of dew Tank gauges
point)
Flowmeters (water, 'sewage,
Manometers (pressure gauges for steam, compressed air,
all gases) high-pressure gases)
Compensating clock pendulums Gyroscopes
Barometers (a type of manometer) High-vacuum diffusion pumps
Weightometers Electric-motor clutches and
seals
According to Bureau of Mines reports, there was a 31% decrease
from 1969 (6,981 flasks) to 1970 (4,832 flasks) in the consump-
tion of mercury for use in industrial and control instrumenta-
tion (1,2). Prior to 1969 the average yearly consumption of
mercury for this manufacturing area was 4,131 flasks. Mo trend
in mercury usage is apparent during the period of 1965 through
1968 (2).
For many applications, no alternatives are presently available
to using mercury in industrial and control instruments. In some
cases, however, substitutions can be made. For example, mechan-
ical gauges and aneroid instrumentation can replace some types
of mercury instruments,
Best Available Level of Treatment and Control
Essentially, there is no mercury discharged to the plant's
sewerage system in the manufacture of instruments. Any elemental
mercury collected in the cleaning of the filling areas is sent to
a refiner.
Particulate mercury is collected in a central vacuum system that
contains traps for liquid mercury, which is filtered, re-distilled,
and reused. Further control is practiced by transferring spilled
or dirty mercury to shipping containers and sending it to a
33
-------
refiner for reprocessing. Cleaning the floor areas in the mercury-
filling sections with U. S. Government approved "HGX" Powder is a
recommended practice. This compound changes mercury to non-vola-
tile, insoluble sulfide. Sweepings are collected in plastic rubbish
bags and deposited with trash in approved land fill areas. There
is some possibility of water contamination from mercury in solid
wastes deposited in land fills.
34
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Dentistry
According to Bureau of Mines reports (1,2) 2,286 flasks of
mercury were used for dental preparations in 197O, as compared
with 3,053 flasks in 1969. In 1968, the dental profession con-
sumed 2,O89 flasks; and prior to 1968 consumption fluctuated
around a relatively constant rate of about 1,5OO flasks annually.
No explanation for the apparently anomalous 1969 usage rate has
been found; however, the decline in 1970 can be at least partially
accounted for by concern over mercury pollution and by a general
economic slowdown (40). Consumption for the first quarter of
1971 was almost identical with that for the last quarter of 1970 (1)
Written evidence of the use of amalgam (an alloy of mercury with
another metal) in dentistry dates back to 1528, and today it
remains the most common therapeutic agent used for restoring
decayed teeth, accounting for three out of four restorations
of individual teeth. Dental amalgam consists of mercury combined
variously with silver, zinc, tin, and copper. The current American
Dental Association (ADA) specification for dental alloy (before
final amalgamation with mercury) lists the following standard
requirements for chemical composition (39):
Silver Min. wt. 65%
Tin Max. wt 29%
Copper Max. wt. 6%
Zinc Max. wt. 2%
Mercury Max0 wt. 3%
To make the final amalgam, this "pre-alloy" is triturated with an
approximately equal amount of mercury. Excess mercury is squeezed
out in a condensation operation, leaving a usable amalgam usually
containing about 50% mercury but sometimes containing as little as
40%. The proportion of mercury remaining in the amalgam after
squeezing is inversely proportional to the logarithm of the
pressure employed (41) and is also affected by the presence of
mercury in the pre-alloy (39).
Amalgams possess a number of physical properties that make them
particularly well-suited to use as dental restorative material.
Ease of preparation in the dentist's office is assured by the
readiness with which mercury amalgamates with other metals.
Amalgams are easy to work and shape, since they are plastic at
body temperature for a few minutes before they harden. Once in
the tooth, they are stable and secure, since the hardening process
35
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involves little or no change in volume. Once hardened, properly
condensed amalgams exhibit compressive strength as high as some
cast irons. They also withstand the corrosive environment of
the mouth and are bland to the host (39).
Acceptable alternatives to the use of amalgams are: alloys of
gold (with small amounts of platinum, palladium, silver, copper,
and zinc), silicate cements, unreinforced acrylic resin; and
reinforced or composite resins. The resins, however, are not
applicable or approved for all dental uses; and the ADA has taken
the position that amalgam and gold are still the best restoration
materials to use (39).
Gold (alloy) has been and is being used as filling material in
dentistry, usually in one of three forms: gold foil, crystalline
or mat gold, and powdered or sintered gold. Powdered gold is not
as easily used or worked as amalgam, but its edge strength is more
than twice that of amalgam (and half that of gold foil)(39). The high
cost of gold is actually the most significant limitation on its
use as a complete substitute for amalgam.
For fillings where aesthetic considerations require matching the
appearance of the natural tooth, silicate cements have long been
used. Powders used for silicate cements are pulverized complex
glasses consisting essentially of alumino-silicates containing
magnesium, fluorine, calcium, sodium, and phosphorus. Modern
silicate cements have sufficient compressive strength to resist
masticatory forces and offer versatility in matching the opacity
and shading of natural teeth. A major weakness of silicate
cements is their tendency to dissolve and disintegrate in the
mouth, especially in areas of the restoration which are not
self-cleansing (39).
Restorative resins are also in limited but growing use in dentistry
where aesthetic considerations are involved. Conventional acrylic
resin (methyl methacrylate) has been used but has drawbacks such as
shrinkage on polymerization, high coefficient of thermal" expansion
compared with tooth material, lack of color suitability, and re-
current decay around and under the filling. Newer composite resins,
which contain inorganic fillers--e.g., glass beads, rods, quartz,
or lithium aluminum silicate—to reinforce the resin, are now
replacing the conventional resins. They have advantages in com-
pressive strength, higher modulus of elasticity, higher hardness
and resistance to abrasion, lower polymerization shrinkage, and
a coefficient of thermal expansion much more nearly comparable to
that of the natural tooth material. Possible disadvantages which
are still under investigation are gradual color changes, surface
roughness and difficulty of finishing, and lack of chemical
adhesion to natural tooth tissues (39). The Council on Dental Materials
and Devices of the ADA has recognized the effectiveness of these
36
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resins for certain types of restorations, but approval for wider
use awaits further clinical investigation (42). Further devel-
opments in this field promise to make restorative resins true
alternatives to both amalgam and gold.
Best Level of Treatment and Control
Each time a dentist places an amalgam restoration, he must prepare
an excess to ensure sufficient amalgam to construct the restor-
ation properly. This excess amalgam becomes waste. Similarly,
the amalgam removed from the filling during shaping is usually
rinsed from the mouth or aspirated and becomes waste which can be
caught in a strainer or trap in the drain. Such scrap can be
recovered from waste traps on cuspidors, aspirators, and evacuators
and placed in a covered container along with the excess unused
amalgam. Since about 50% of the scrap is mercury and 25% or more
is silver, reclamation is economically worthwhile. Under the
best level of control, no soluble mercury should be discharged
if a properly designed waste trap is used. Although the use of
waste traps is common among dentists, no data or estimates of
amounts of recovered and discharged mercury are available (43).
37
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Laboratory and Hospital Uses
According to Bureau of Mines reports (1,2), the consumptive use of
mercury in laboratories decreased by 11.5% from 1969 (2,O41 flasks)
to 1970 (1,806 flasks). However, no trend in laboratory use of
mercury is evident in the years 1965 through 1968. The average
number of flasks of mercury consumed per year during this time
period (1965-1968) was 1,265 flasks.
Mercury and mercurials are standard laboratory items used as
reagents and indicators, for calibration and sealing, and in
instruments and vacuum pumps. Since for many research applications
the unique properties of mercury make it indispensable, the em-
phasis in this area must be on treatment and control.
Medical diagnosis and operations use mercury for specific applica-
tions. Radioactive mercury plays an important part in the area of
diagnosis. The antiseptic qualities of mercury also are utilized
in hospital operating room practices.
197 203
Radioactive mercury ( Hg, Hg) can be used for brain scans for
tumors, and for renal scanning. Neohydrin (^^Hg) is used in
brain scanning since it is more accurate in the demonstration of
metatastic lesions, and it seems to obtain clear delineation of
lesions in parasagittal sinus, brain bases, and posterior fossa
(44) «, Renal uptake of mercury (-^'Hg) depends on renal function.
The uptake value of l^Hg, measured by external counting, allows
the quantitative estimation of the functional value of each
kidney (45).
Mercuric chloride, Oa2% (1:500) has been used in the prevention of
suture line recurrences in anterior resection for colonic cancer
(46).
Alternatives to the Use of Mercury
Laboratory
No respondent using mercury or mercurials for laboratory purposes
suggested any available alternatives to such use. It is likely
that particular mercury compounds used as chemical reagents can
be replaced by non-mercurials, but no specific examples can be
cited.
Hospital
Technetium ( Tc), radioactive potassium carbonate ( K), and
diiodofluorescein (-'--^-'-I), may be used in place of radioactive
mercury for brain scans (21,47)0 An alternative to mercuric
38
-------
chloride could be centrimide (1% solution). It has been shown to
be effective in preventing growth of tumor cells in experimental
wounds (46).
Medical considerations must govern in this area, and recommenda-
tions can be made only by medically qualified investigators0
Best Available Level of Treatment and Control
Because of the nature of laboratory and hospital operations,
there is almost no danger of continuous large effluent flow
containing unacceptable concentrations of mercury. The danger
is in careless or accidental disposition of relatively small
amounts of expended mercurials down the drain and in careless
handling of spilled metallic mercury. In a laboratory and
hospital context, the best available level of treatment and
control consists of conscientious practice of routine methods
such as:
a. Precipitation of dissolved mercury compounds for recovery
or safe disposal as solid waste.
b. Separation of suspended mercury compounds for recovery or
safe disposal as solid waste.
c. Chemical treatment or fixation of spilled metallic mercury
before vacuuming or washing, with subsequent precipitation
or separation of mercury for recovery or safe disposal as
solid waste.
39
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Mercury Reclamation
Many companies process mercury-containing substances (especially
dental amalgam and contaminated metal) for the recovery of
elemental mercury. A typical process is the operation of one-liter
stills under vacuum to recover the mercury. The still is heated
to temperatures allowing the mercury to vaporize and to be carried
through a condenser to recovery.
The recovery process involves washing stages using acid and/or
water. Acid wash is reused, but wash water is discharged to sewers.
Although this water may contain up to 25 ppm dissolved mercury,
the amount discharged is relatively insignificant. Recovery of
mercury from an operation processing two to three tons of amalgam
and metal annually involves discharge of less than 1000 gallons
of wash water per year.
Best Available Level of Treatment and Control
Physical control is exerted in the reclamation of mercury by
having no drains in the building and having sinks equipped with
traps which are cleaned once a week. The sludge remaining from
the distillation of the mercury-laden substances is dumped into
containers and reprocessed. Cleanup of the refining area is per-
formed with a vacuum after washing with an inorganic sulfide. The
material generated from this cleanup operation is also sent out
for further mercury reclamation.
40
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SECTION III
OTHER TREATMENT AND CONTROL METHODS
This section includes actual or possible methods of treatment and
control that were either reported by industry, but not equivalent
to the best available methods, or reported in the literature and
generally applicable to more than one industry. Tables 3 and 4
summarize those treatment methods for which sufficient information
is availableo
Chemical Production
1. An experimental metal reduction process for removing mercury
from industrial waste water has been tested by Merck Sharp and
Dohme Research Laboratories (48). The addition of powdered zinc
to effluent from a plant producing organic and inorganic mercurials
resulted in the removal of over 99% of the mercury by the formation
of filterable zinc-mercury complex. A mean effluent level of
O.O21 Ib/day (estimated by the present writers from tabulated
data as a mean concentration of O.6 mg/1) was obtained by using
3.8 pounds of zinc per pound of mercury. On an experimental
scale, the method appears to be both effective and economical.
Further research is being conducted on the nature of the reaction
mechanism, on modifications required to adapt the method to large
volume flows having a low initial mercury level, and on alterna-
tive metals (e.g., aluminum) to use in place of zinc.
2. One example of claimed total control was found, but its
applicability is extremely limited. A producer of English
Vermilion pigment (49), which is mercuric sulfide, uses a
process as shown in Figure 9.
Mercury
Sulfur
Caustic Soda
(Catalyst)
Water
Agitated
Container
(Sealed)
Wash
Tank
Filter
Box
Product to Drying
Oven and Packaging
Wash Water
to Sewer
Figure 9n Mercury Control in Production of English Vermilion
41
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TABLE 3. SUMMARY OF OTHER TREATMENT METHODS BY INDUSTRY
Industry
Treatment Process
Effluent Data--
Mercury
Concentration
Chemical Production Metal (zinc) reduction
Manufacture of
mercuric sulfide
Use of catalysts
Chlor-Alkali
Filtration and stoich-
iometric proportioning
Chemical precipitation
Sodium hydrosulfide
plus/or
Ferrous chloride
Ion exchange
(brine treatment)
Treatment of brine
with formaldehyde
O.021 Ib/day
(99% removal)
No discharge
0.3 to 0.5 Ib
Hg/day; 0.025 Ib
Hg/100 tons C1Q
O.3 ppm
1 ppm
42
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TABLE 4o SUMMARY OF OTHER TREATMENT METHODS BY TREATMENT PROCESS
Treatment Process
Applicable Industry
Effluent Data—
Mercury
Concentration
Chemical Processes
Metal (zinc)
reduction
Chemical pre-
cipitation
Sodium hydrosul-
fide plus/or
Ferrous chloride
Ion exchange
Treatment with
fo rmaldenyde
Physical Process
Filtration and
stoichiometric
proportioning
Chemical Production
Catalytic wastes
Chlor-Alkali
Chlor-Alkali
(brine treatment)
Chlor-Alkali
(brine treatment)
Chemical Production
(Manufacture of
mercuric sulfide)
0.021 Ib/day
(99% removal)
0.3 to 0.5 Ib
Hg/day; 0.025
Ib Hg/100 tons
ci2
O.3 ppm
1 ppm
No discharge
43
-------
Since HgS is the most insoluble form of mercury, with specific
gravity of 8.0, it is completely separated from the wash water
by the 36 x 34 twill fabric filter medium. No unreacted
mercury is involved, since the raw materials are reacted in
stoichiometric proportions and fully recovered as product<,
Paint Industry
Paint companies can reduce the amount of mercury in the effluent
streams by reducing the number of washings of tanks in which
paints are manufactured.
Treatment of Catalyst Wastes
An effective method for purifying waste waters involves heating
them with KCIO^ (converting all Hg to HgCl2) and subsequent
precipitation of Hg++ as HgS. A residue obtained from treatment
of sulfonic acids with iron shavings of Na^S contained HgS, Hg,
anthraquinone, and its sulfonic acids. The residue was boiled
with a mixture consisting of KC1O0, NaCl, and H-SO., which re-
-j £* f\
suited in conversion of Hg and HgS to HgCl and precipitation of
organic impurities which were then filtered off and wahed free
of HgCl2» Practically pure HgS, suitable for processing in Hg
factories, was precipitated (with Na£S) from the mixture of
filtrate and wash water (5O).
Chlor-Alkali Industry
1. A flow diagram showing an effluent treatment commonly used in
the chlor-alkali industry is depicted in Figure 10. This method
results in a discharge of 0.3 to 0.5 pounds of mercury per day.
Since the total effluent flow was not given, the Hg concentration
in the final effluent discharge could not be calculated.
Brine Purge
Condensates
Wash Water
Drainage
_y«_ w>
\-s^r.
2r »>
HC1 addition
to a 3 pH _
NaHS addition
(0.3
Settling
Pond
Filtration
t
Discharge
to O . 5 pounds of Hg/day )
Figure 1O. Treatment of Chlor-Alkali Effluents
44
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2o A manufacturer of mercury cells (Hoechst-Uhde Corp.) discussed
a process flow sheet of mercury emissions from a mercury cell at a
symposium on chlorine at Buck Hill Falls, Pennsylvania, on May
21-22, 1970 (51). However, a discussion with Mr. Edmund Laubusch,
Technical Manager of the Chlorine Institute, revealed that the claims
made in the following discussion should be viewed with caution.
Judicious judgment of the data presented is needed because the
amount of mercury wasted per 100 tons of chlorine produced is
reported to be O.025 pounds. (This figure was calculated from the
given information that the described Hoechst-Uhde process had a
mercury loss in the waste water of O.14 grams/metric ton of C^
produced.) This value (O.025 Ib) is far lower than previously
reported values (O.1O Ib Hg discharged/100 tons do produced) by
General Technology Corporation's EPA-WQO Interim Report (29).
The following discussion is from a paper (52) by Dr. Bernd Strasser,
presented at the symposium:
"The total quantity of technological mercury losses encountered
in the Hoechst-Uhde mercury cell process is normally less than
2O grams of mercury per metric ton of chlorine. Figure 11
shows the distribution of these losses. It will be noted xnat
the major portion, that is about 62%, is entrained by the hydro-
gen whose temperature has been reduced to 30°C. This cooling
step should preferably take place at the decomposer exit which
eliminates losses due to mechanical handling and because the
mercury inventory in the cell can be controlled more efficiently.
"The hydrogen cooler is part of the standard equipment of the
Hoechst-Uhde cell. A further reduction of the mercury quantity
entrained by the hydrogen is achieved by cooling the hydrogen
to a lower temperature or by a combined compression and cooling
step. Through adsorption by activated carbon or chemisorption
by iodine-activated carbon, the mercury content of the hydro-
gen can be reduced to 3 milligrams per ton of chlorine and 6
milligrams per ton of chlorine, respectively. When using a
catalyst developed by Farbenfabriken Bayer AG, a residual
content of only 3 milligrams of mercury per ton of chlorine
can be achieved.
"The mercury content of the 5O% caustic soda solution can be
reduced from 3 grams to about O.45 grams per ton of chlorine
or less by means of precoat filters.
"The exit brine from the cells contains certain quantities of
mercury in the form of a complex solution. The mercury content
of the inlet brine is lower by the mercury quantity which is
precipitated during alkalization and entrained by the filter
sludge from the brine system.
45
-------
46
-------
"The difference in mercury content before and after precipita-
tion, that is the mercury lost together with the filter sludge,
depends on the mode of operation of the brine system; empirical
figures range from 2.5 to 10O grams of mercury per ton of
chlorine. The mercury can be recovered, indeed, from the
filter sludge by various methods which are, however, relatively
complex and fairly expensive. It is possible, nevertheless,
to reduce mercury losses in the brine system to a minimum
without having to apply said complex procedures for demer-
curizing the sludge and brine. The specific procedures used
by Farbwerke Hoechst AG are based on maintaining oxidizing
characteristics of the brine even during precipitation and
filtration to prevent the precipitation of mercury. In this
way, the amount of mercury going into the sludge of the brine
purification will not exceed the portion that corresponds to
the percentage of brine in the sludge. The mercury losses
can be reduced from 2.5 grams additionally theoretically to
zero by washing the sludge and additional chemical treatment
of the waste water containing iogenic mercury.
"A small percentage of mercury is lost in the waste water
which comprises:
"The condensate from the hydrogen cooling systems, wash water
from the filters, end boxes and feed boxes, flushing water
from the cells, from the cell room floor, etc.
"For reducing these losses it is possible, for example, to
backwash the filters with brine and to return to the process
at least part of the condensate from the end boxes and
feed boxes. Other water streams can be freed of metallic
mercury by means of precoat filters and from ionic mercury
as already mentioned in the recovery of the brine sludge.
"Modern cells have practically eliminated mercury losses caused
by the discharge of ventilation air. The exhaust air from
the end boxes can be considered as being free of mercury.
The latest design of the Hoechst-Uhde cell has eliminated any
mercury loss in the exhaust air from the feed boxes. The
feed box is of the totally closed design and is connected
to the hydrogen system.
"These are the main aspects of mercury losses. If procedures
are used as in discussed here, mercury losses can be held
in the order of about 4 grams per ton of chlorine or less.
"Engineering advances made in recent years have also drastically
reduced the mercury losses previously encountered through
the mechanical handling of mercury, that is through daily
routine operations performed in the electrolysis plant (for
47
-------
example filling and refilling cells with mercury, cleaning of
cells, and so on). Today, mercury losses in new plants can be
reduced to 5 to 10% of the figures encountered in I960."
3o Dechlorinated spent brine is sent through a column of quater-
nary ammonium ion exchange resin, where mercury is adsorbed as
HgCl^. Treatment with Na2S forms sulfide and polysulfides of
mercury, which can be oxidized to Hg(II) sulfate by chlorine-
containing brine. The sulfate can be returned to the electro-
lytic cell, where it is reduced to Hg metal at the cathode (53).
4. Mercuric ions have been removed experimentally from brine by
contacting the brine with certain glycine copolymers which act as
selective ion exchange resins. A synthetic brine containing 15
ppm mercuric ions was treated, with a reduction of Hg++ ions to
0.3 ppm (54).
5. Dissolved mercury compounds can be removed from solution by
reduction to the metallic state. Reducing agents that can be used
in brine include aldehydes and carboxylic acids (55). Experimental
treatment with formaldehyde of brine containing 69 ppm mercury
reduced the mercury content to less than 1 ppm (56).
6. Methods of Waste Water Control in Operation of a Mercury Cell (7)
Cells
a, Endbox periodic flushing. Control by recycling as much of
flushings as possible. Send purge to final treatment system.
b. Sloppings or spilling of brine during cell start-up., Start
up cells with alkaline brine and remove metallic impurities
in brine filtering system.
c. Cell washout water to clean out cell during cell maintenance.
Recycle wash water as much as possible. Send "spent" wash-
out water to final treatment system.
Hydrogen Stream
a. Cooling water in direct contact coolers. Use condensate to
cool hydrogen and recycle condensate to decomposer chamber
or convert to indirect cooling.
b. Condensate drips in indirect coolers. Recycle condensate drips
to decomposer.
48
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Caustic Stream
a. Backwash from caustic filters. Impound solids for mercury
recovery. Send clear liquor to final treatment system.
b. Caustic tank cleanouts including storages and tank cars.
Wash waters having useful alkali values returned to plant0
Dilute wash waters recycled as much as possible, then send
to final treatment system.
Brine System
a. Purge brine. Send necessary brine purges to final treatment
system.
b. Brine filter backwash. Impound solids for possible mercury
recovery or send solids-liquor mixture to final treatment
system. Conversion from sand filters to leaf filters may be
justified as a means of reducing volume to be treated.
Cell Room
a. Cell maintenance area. Collect solid refuse such as spent
anodes, etc. for possible mercury recovery. If mercury
recovery is not possible, permanently impound.
b. General wash water. Curtail and recycle as much as possible,
install tanks or weirs to settle out recoverable mercury and
send water to final treatment system.
Switches and Rectifiers
The following procedure is in use to control mercury0 The mercury
coming from the distributor goes into an "oxifier"* for 5 to 6
hours for exposure to air which is pumped in. Baffles in the
"oxifier" help mix the mercury. From the "oxifier," the mercury
is placed into settling jars. The fines (mercury oxides) come
to the top and the mercury is drawn off the bottom, leaving a
1%" mercury layer (containing the fines) on the bottom of settlers.
Fines are placed in a separate jar and emptied into a larger jar
every month. Finally, every 6 months these jars are recycled back
to the "oxifier" for reprocessing.
When the mercury is drawn off the bottom of the settling jars, it
passes through a gold adhesion filter into a dispenser bottle. The
filter removes all contaminants except noble metals. The dispenser
is then used to hand-fill the glass switch,, After filling, the
*Oxifier manufactured by Bethlehem Apparatus Company, Hellertown,
Pennsylvaniao
49
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switch is sealed and is checked for leaks. The mercury from any
leaky switch is reprocessed as is the mercury picked up by the
vacuum cleaner used to clean the troughs at the edges of the
manufacturing benches. Vacuuming is performed once a week.
Another procedure is to use stainless steel drip trays to catch
spillage. The surface of the caught mercury is flooded with water
to minimize evaporation. Waste mercury is returned for refining.
Generally, no mercury leaves either of these production areas such
that it could enter a sewer or pollute a stream.
General Treatment Methods
General treatment methods which are applicable to mercury-bearing
waste streams but are not in themselves the best available methods
are discussed below.
1. One of the most common, simplest, and most effective methods
to remove mercury from solution is precipitation of an insoluble
mercury compound (57). Sodium sulfide (Na2S) and sodium hydro-
sulfide (NaHS) are effective in forming the extremely insoluble
HgS. This method is not favored, however, when recovery of mer-
cury is desired, since offensive and poisonous hydrogen sulfide
(H S) gas is formed in the reduction process.
£
2. Another treatment system developed by Aktiebolaget Billingsfors-
Langed is based on a special ion-exchange resin, Q 13, which posse-
ses an affinity for mercury, even in the presence of sodium chloride.
Metallic mercury content is oxidized with chlorine, the pH con-
trolled to 5-7, and the waste then dechlorinated prior to ion-
exchange with Q 13. Two ion-exchangers in series are recommended,
with the final effluent at 0.1-0.2 ppm mercury. Regeneration is
acidified brine, recovering mercury to the brine circuit. A
final absorption filter of their design should drop the mercury
content to 0.01-O.02 ppm mercury (7).
3. Cellulose ion-exchange fibers have been used to purify mercury-
containing waters, absorbing 4.3 equivalents Hg per kilogram (58).
4. Flocculation can be effective, in conjunction with a precipi-
tation method, for control and recovery of mercury from solution.
After precipitation, dispersed HgS can be scavenged with gelatinous
Fe(OH).g, which is formed by the addition of FeCl3 and starch with
pH adjusted to 10 with NaOH. In effluent containing appreciable
amounts of Fe+3 ion, Fe(OH)3 can be formed by addition of Ca(OH)
or CaO (59,60).
5. A possible generally applicable method for waste water treat-
ment is to precipitate mercury with an alkali sulfide with simul-
taneous or subsequent addition of iron or zinc salts for floccu-
50
-------
lation (61). The iron or zinc salts also prevent the formation
of soluble mercury-sulfide complexes (e.g., Na2HgS2). An experi-
ment with industrial waste containing 15 to 25 mg Hg/1 involved
precipitating HgS with NaHS in the presence of ZnCl2 or FeSC>4,
leaving a residual Hg concentration of 0.003 to 0.01 mg/1 (62).
6. Filtration with adsorptive compounds can be used to remove
mercury from solution. Some of the compounds found to be effective
in experiments are: activated carbon (63), graphite powder (64),
graphite dust plus serpentine-asbestos dust additive (for alka-
line solutions) (65), and wool fiber (66).
7. For mercuric ion in acidic solutions, hydrazine hydrate can
be used to reduce more than 99% of the mercury to the metallic
form (67).
51
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SECTION IV
RESEARCH NEEDS
Many treatment processes have been described in the literature
and have been tried by several companies in attempting to meet
tentative water quality standards for mercury. We recommend
an extensive research program for those industries where no
alternative for the use of mercury is available,, This research
and development program should have its emphasis on examining
the merits of the following treatment methods for implementa-
tion in the field.
1. Sodium Hydrosulfide plus Activated Carbon Process
2. Osaka Soda Process
3. Aktiebolaget Billingsfors-Langed Process
4. Terraneers, Limited Process
5. Ventron Corporation Process
6. Zinc Dust Process
*
Outline of Approach
This program of comparative studies on these different treat-
ment methods of mercury-bearing effluents can be accomplished
by Federal financial and technical assistance for pilot plant
and demonstrational projects., These types of Federal programs
allow industry and government to share equally the burden of
the costs of research and development for solving the complex
problem of mercury in waste water effluents.
Specific companies to be contacted for this research program
are detailed below in conjunction with further steps in the
research program.
A. Select a paint company, a chemical manufacturer, a
chlor-alkali producer (mercury cell), and a company
using mercury as a catalyst to test these methods
on a pilot plant scale.
B. Determine reaction-limiting conditions with respect
to each treatment process. Several of these processes
may be affected by physical and/or chemical conditions
present during the treatment of the plant's wastes.
For example, pH or chelating agents may determine
whether the efficiency of removal is 50% or 90%.
53
-------
Compile results of pilot plant scale study and implement the
one treatment process or combination of processes suitable
for the entire industry,,
54
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SECTION V
CONCLUSIONS
1. Many treatment methods for industrial waste water effluents,
typically containing more than 1 ppm mercury, can remove up to
99% of the mercury. However these methods individually are not
efficient enough to produce a condition where no mercury is dis-
charged. It appears that treatment of effluents with combinations
of methods will be necessary to approach or achieve this condition.
The best currently available treatment methods for industrial
effluents can reduce mercury content to less than 5 ppb. No actual
or proposed method appears capable of achieving levels below 1 ppb.
See Table 5 for a summation of treatment methods by industry.
2. The actual and foreseeable banning of all (or nearly all)
mercury compounds for use in agricultural chemicals has already
caused major reductions in the amounts of these products on the
market. Except in specialized instances, nonmercurial alternatives
are being used with equal or better effect.
3. The catalytic use of mercurials in the production of vinyl
chloride monomer, sulfonated anthraquinone, and certain urethanes
generally can be eliminated. Present technology has produced less
environmentally damaging processes replacing mercury catalysts in
the production of these three materials.
4. Research is presently being conducted to find alternatives to
using mercurial additives to paint. The paint industry says two
years will be required before fully tested substitutes will be
available.
5. Mercuric oxide has been eliminated from use as a biocide in
antifouling paints, and replaced by cuprous oxide and tributyltin
oxide. It is, however, still registered under the Federal Insecti-
cide, Fungicide, and Rodenticide Act.
6. Nonmercurial substitutes exist for the most common pharmaceu-
tical and cosmetic mercurials. However, medical consideration
(e0g., side effects, toxicity, site and specificity of activity)
rather than environmental effects must ultimately dictate the
product choices. Treatment and control must be emphasized.
7. The pulp and paper industry has stopped using phenyl mercury
slimicides. These compounds have been replaced by an array of
different compounds such as organo-sulfurs, thiocyanates, and
chlorinated phenols. However, some of the chemicals this industry
is using in its processing of paper are contaminated with trace
quantities of mercury.
55
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TABLE 5. SUMMARY OF BEST AVAILABLE
TREATMENT METHODS FOR EACH INDUSTRY
Industry
Treatment Process
Effluent Data—
Mercury
ConcentratIon
Removal
Mining
Chemical Production
Agricultural Chemicals
Catalytic Wastes
Paint
Pharmaceutical
Pulp and Paper
Chlor-Alkali
Plant waste water
Soil Filtration
1. Cationic
polymer floccu-
lation
2. Osaka Soda
(ion exchange)
3. Sodium boro-
hydride plus che-
lating resin
4. Proprietary—
Terraneers, Lim-
ited
1, 2, 3, 4
(as above)
Holding and re-
cycling wash waters
or solvent sludge;
If 2, 3, 4
(as above)
1, 2, 3, 4
(as above)
1, 2, 3, 4
(as above)
If 2, 3, 4
(as above)
Sodium hydro-
sulfide and/or
ferrous chloride
plus activated
carbon bed
Caustic Purification Filtration
Electrical
Batteries
Lamps
Switches and
Rectifiers
Industrial and Control
Instrumentation
Dentistry
Laboratory and
Hospital Uses
Extruded dough
processi no dis-
charge
Mercuric oxide
production:
treat with sodium
sulfite
Zinc amalgam
production: set-
tling and zinc
amalgamation
No discharge
No discharge
No discharge
Waste traps
Routine
precautions
No Hg detected
downstream
2.5 to 15 ppb
2 to 5 ppb
Potentially
1 to 5 ppb
1O ppb
None
99% suspended
solids
6O% COD
75% phenyl
mercurials
10 to 2O ppb
O.O5 to 0.25
Ib Hg/100 tons
C12
O.O5 ppm
99.7% mercury
2.5 ppm
0.5 ppm
56
-------
8. Although the mercury cell can technically be replaced by the
diaphragm or the Downs cell in the chlor-alkali industry, the
caustic produced by the latter two types is not suitable for some
industries. Unless quality of caustic produced by the diaphragm
or Downs cell process can be improved, the emphasis in this
industry must be on treatment and control of mercury discharges
rather than substitution for the mercury cell.
9. Lamp manufacturers do not discharge mercury into water, but
they do dispose of rejects in sanitary landfills. Process losses
of mercury appear to be confined to evaporation.
10. In the manufacturing of mercury switches and rectifiers, no
discharge of mercury is made to the sewerage system. Mechanical
or solid state switches can be used as substitutes, but the
minimal hazards associated with the production of mercury switches
do not warrant their replacement. Mercury rectifiers can be
replaced by selenium or silicon rectifiers.
11.* Industrial and control instrumentation manufacturers have few
alternatives to using mercury except to substitute mechanical
gauges and aneroid instrumentation. However, the substitutions
may not be warranted since there are no mercury discharges from
these manufacturerSo
12. Present dental research on the replacement of amalgams as
restoratives should in the near future produce substances
capable of replacing mercury successfully for most dental
applicationso-
13. The laboratory and hospital uses of mercury can not be
avoided, but the judicious use and disposal of mercury and its
compounds will help to avoid the introduction of mercury into
the sewerage system.
14. The industries of electroplating, jewelry casting,-hat
making, and explosives manufacture have abandoned products or
processes involving mercury.
57
-------
SECTION VI
RECOMMENDATIONS
1. Study of economic considerations for the alternatives to using
mercury and its compounds in individual industries is recommended.
2. Serious consideration should be given to requirements for
accounting of all elemental mercury purchases, uses, and disposal
by every user.
3. An in-depth study should be performed to evaluate the trace
contamination of mercury in chemicals used in the production of
consumer products.
4. In the paint industry, the control method of holding the wash
water used in cleaning equipment after a batch paint mix is
recommended since no mercury will be discharged.
5. Battery manufacturers should evaluate the process of chemically
handling mercury in a dough-like material before placement in the
battery casings, since this method does not produce any concentra-
tion of mercury in the final effluent.
6. Recycling and recovery of mercury in electrical products should
be investigated and encouraged.
7. The American Dental Association should establish specifications
or standard procedures for installation and use of traps in dental
office sinks to capture the excess amalgam from tooth fillings.
8. All laboratory personnel should be trained in the proper use,
treatment, and disposal of mercury and its compounds. The hazard-
ous nature of these materials should be continuously and prominently
emphasized (e.g., by posters) in the actual working areas.
9. Hospitals should be studied for the number of hazardous materials,
such as mercury, which they discharge into municipal sewerage systems.
1O. A medical committee should be established to assess the need to
use mercury and its compounds in treatment and diagnosis.
59
-------
SECTION VII
REFERENCES
1. "Mercury in the First Quarter 1971." Mineral Industry Surveys,
U. S0 Department of the Interior, Bureau of Mines, Division of
Nonferrous Metals, Washington, May 26, 1971„
20 "Mercury," Preprint from the 1969 Bureau of Mines Minerals
Yearbook, U. S0 Department of the Interior, Bureau of Mines.
Washington: U. S. Government Printing Office, 1970.
3e Jo H. Bernstein, Operations Manager, Ventron Corporation;
private communication, April 23, 1971.
4. "Osaka Soda Mercury Recovery Process." Information bulletin
supplied by Crawford and Russell,Inc., Stamford, Connecticuto
5. Rosenzweig, Mark D0 "Paring Mercury Pollution," Chemical
Engineering, February 22, 1971.
60 Do K. Larsen, De Soto, Inc.; private communication, May 13,
1971.
7. Clapperton, J0 A0 "Ecology-Pollution Aspects of Chlor-
Alkali Plants: Mercury Abatement Ad Hoc Mercury Committee,"
presented at the Chlorine Plant Managers' Seminar, New
Orleans, February 3, 1971.
80 Chlorine Institute Summary - Bureau of Mines Data - Mercury
Consumed in the U. S0 Provided by Edmund J. Laubusch, The
Chlorine Institute, Inc., April 1, 1971.
9. Ranney, Cc D« "Effective Substitutes for Alkyl Mercury
Seed Treatments for Cottonseed," Plant Disease Reporter
55:3, March 1971.
lOe Ryker, T. C. "Changes in Concepts in Seed Treatment and
Treatment Materials,," Presented at the 20th Annual Short
Course for Seedmen, Mississippi State University, April
19-21, 1971.
110 Lutz, G. A., et al. "Design of an Overview System for
Evaluating the Public-Health Hazards of Chemicals in the
Environment," Battelle Memorial Institute, prepared under
Public Health Service contract no. PH 86-66-165, July 1967.
12. National Materials Advisory Board, Trends in Usage of
Mercury, NMAB-258, NRC, NAS-NAE, Washington, D. C., Septem-
ber 1969.
61
-------
13. "Sulfonation and Sulfation," in Kirk-Othmer Encyclopedia
of Chemical Technology, Second Edition, New York: Inter-
science Publishers, 19630
14. Mercury, Metal Horizons 1, Reprint from Metals Week, March
1967. Cited in "Economic Analysis of the Mercury Industry,"
prepared for the General Services Administration, Contract
GS-OO-DS-(P)-850O5, by Charles River Associates, Inc., Cambridge,
Massachusetts.
15. Broome, T0 T. and E0 J. Lowrey0 "Mechanism for Film Preser-
vation by Phenyl Mercurials on Wood Substrates," J» of Paint
Technology, 42(543):227, April 1971.
16. Mann, Aa "Mercurial Biocides: Paint's Problem Material,"
Paint and Varnish Production, March 1971.
17. Robert A. Roland, National Paint, Varnish and Lacquer Asso-
ciation, Inc.; communication to Mr. Lowell E. Miller, Acting
Director, Pesticides Regulation Division, U. So Department of
Agriculture; February 1, 1971.
18. Royal A. Brown, National Paint, Varnish and Lacquer Associ-
ation, Inc.; private communication, June 22, 1971,,
19. "Antiseptics and Disinfectants," in Kirk-Othmer Encyclopedia
of Chemical Technology, Second Edition, Volume 2. New York:
Interscience Publishers, 1963.
20. Tonomura, K., et_ al_. "Stimulative Vaporization of Phenyl-
mercuric Acetate by Mercury-Resistant Bacteria," Nature, vol.
217, p. 644 (1968).
21. Stecher, Paul G. (ed.). The Merck Index, Eighth Edition.
Rahway, N0 Jo: Merck & Co., Inc., 1968.
22. Alves D'Assumpcao, Evaldo. "Use of Mercurochrome in the
Treatment of Burns" (abstract). Biological Abstracts, vol. 51,
p. 27,755 (1970)=
23. "The alternatives to mercury-based system additives." Chem
26 Paper Processing, 7(2):32, February 1971.
24. "Draft Report on Waste Profiles of the Paper Industry."
Prepared for the EPA Water Quality Office under contract nos.
68-O1-0012 and 68-01-0022 by WAPORA, Inc., Washington, March 5,
1971.
25. Edmund J. Laubusch, The Chlorine Institute, Inc., private
communication, May 24, 1971»
62
-------
26o Chlorine Facts, The Chlorine Institute, Inc,, New York, N. Y.
1968.
27. Shreve, R. N0 Chemical Process Industries, 2nd ed. New York:
McGraw-Hill, 1956.
28» Edmund J0 Laubusch, The Chlorine Institute, Inc.; private
communication, June 17, 1971„
29. "Industrial Waste Study of Inorganic Chemicals, Alkalies and
Chlorine." Interim Report, Contract No. 68-01-O020, EPA-WQO,
April 13, 1971, prepared by General Technologies Corporation,
Reston, Virginia0
30. P. R. Mallory & Co., 1968 Annual Report, pp. 15-16.
31. Williamson, O. R0 "Mercury Prices and Consumption," Colorado
School of Mines Mineral Industries Bulletin, VIII, 3, (May 1965)
pp0 1-18. Cited in "Economic Analysis of the Mercury Industry,"
prepared for the General Services Administration, Contract
GS-OO- DS-(P)-85O05, by Charles River Associates, Inc., Cambridge,
Massachusettso
32. Donald G. Wilson, P. R. Mallory & Co. Inc., private communi-
cation, June 28, 1971.
33. Paul Mo D. Harrison, P. R. Mallory & Co. Inc., private commu-
nication, May 3, 1971.
340 Frank O. Sullivan, Union Carbide Corporation, Consumer Products
Division; private communication, May 17, 1971.
35. Unglert, M. C. and D. A. Larson,, "New Era for Mercury Lamps,"
Westinghouse Engineer, July 19650
36. John W0 Newton, Sylvania Electric Products, Inc., private
communication, May 24, 1971.
37. Dr. Atkinson, Westinghouse Electric Corp., private communica-
tion, May 13, 1971.
38„ Electronic company requesting to remain anonymous, private
communication, May 1971.
39. Guide to Dental Materials and Devices0 Fifth edition, 1970-
19710 American Dental Association, Chicago, 197O.
40. "Mercury in 1970." Mineral Industry Surveys (Preliminary),
Uo So Department of the Interior, Bureau of Mines, Division of
Nonferrous Metals. Washington, December 14, 1970.
63
-------
41. Simons, E0 N. "Mercury," in Guide to Uncommon Metals. New York:
Hart, 1967.
42. Stanford, John W. "The Current Status of Restorative Resins-"
Dental Clinics of North America, 15(1), January 1971.
430 Rupp, N. W. and G. C0 Paffenbarger. "Significance to Health of
Mercury Used in Dental Practice." JADA Council Report to be pub-
lished June 1971.
44. Hayakawa, R. "A comparison of 203Hg-Neohydrin and 49Tc pertech-
netate brain scanning" (abstract)0 Biological Abstracts, 52:21,207
(1971).
45. Raymond, C., D. Ricard, Y. Karam, and C. Kellershohn. "The use
of the renal uptake of l^^Hg as a method for testing the functional
value of each kidney," Journal of Nuclear Medicine, 11:125-132
(1970).
46. Gibson, G0 R°, K0 B0 Lawrenson, and F. O0 Stephens. "Comparison
of the use of centrimide, mercuric chloride, and ether non-urigant
solutions in eradicating malignant cells from experimental operation
wounds," Cancer, 26:76-80 (197O).
470 Buchanan, C0 Ro "Comments from the AEC on 197Hg - Chlormerodrin,"
Journal of Nuclear Medicine, 9:5O2 (1968).
48„ Rickard, M. D. and G0 Brookman. "The Removal of Mercury from
Industrial Waste Waters by Metal Reduction." Merck Sharp & Dohme
Research Laboratories, Rahway, New Jersey.
49. Private communication from a chemical company requesting to re-
main anonymous, May 1971.
5O. Genkin, N. "Removal of Mercury from Finished Products and Waste
Waters from Production of Anthraquinone Sulfonic Acid" (abstract).
Chemical Abstracts 62:11523 (1965).
51. Transactions - Symposium on Chlorine. Hoechst-Uhde Corp., Buck
Hill Falls, Pennsylvania, May 21-22, 1970.
52. Strasser, Bernd. "The Hoechst-Uhde Cell. Mercury Emissions and
Provisions for their Limitation." In Transactions - Symposium on
Chlorine,, Hoechst-Uhde Corp., Buck Hill Falls, Pennsylvania, May
21-22, 1970.
530 "Ion Exchange Process for Removal and Recovery of Mercury in Spent
Brine from an Electrolytic Cell with a Mercury Cathode" (abstract)„
Belgian patent no. 633,869. Chemical Abstracts 60:1413OF (1964).
American patents have also been issued for similar processes„
64
-------
54. Calkins, R. C., R. A0 Mock, and L. R. Mevis. "Removal of
Mercuric ions from Electrolytic Solutions" (abstract). U. S.
patent no. 3,083,079. Chemical Abstracts 59:4799C (1963).
55. Fehl'ing, J., et alo "Reduced Mercury Losses during the Electro-
lytic Production of Alkali Hydroxide" (abstract). British patent
no. 1,121,408.. Chemical Abstracts 69;92425T (1968).
560 Neipert, M. P. and C. K. Bonc "Recovering Mercury from Brine
from Electrolytic Cells" (abstract)„ U0 S. patent no. 2,885,2820
Chemical Abstracts 53:13848C (1959).
57o This method is mentioned in numerous references and is included
here for the sake of completeness.
58e Rogovin, Z«, A., et al. "Purification of Mercury-containing
Waste Waters" (abstract). Chemical Abstracts 65:15063C (1966)„
59. Bergerson, G. L. and C. K. Bon. "Mercury Recovery from Electro-
lytic-cell Brine Effluents" (abstract). U. S. patent no. 2,860,952.
Chemical Abstracts 53:128951 (1959).
60o Kotulski, B. "Removal of Mercury from Sewage by Means of Lime"
(abstract). Chemical Abstracts 69:217645 (1968).
61. Zverev, B. P., ejt al. "Removal of Mercury Compounds from Waste
Waters" (abstract). USSR patent no. 142,961. Chemical Abstracts
56:13979 (1962).
62. Gol'dinov, A. L., et_ al_. "Purification of Aqueous Wastes from
Mercury" (abstract). Chemical Abstracts 58:13598H (1963).
63. Irukayama, K. "Elimination of Mercury Waste Water" (abstract).
Chemical Abstracts 73:123355J (1970).
64. Nikovskaya, V. A. "Lowering the Mercury Content in Caustic Soda
Resulting from a Mercury Process" (abstract). Chemical Abstracts
72:33752M (1970).
65. Chviruk, V. P., et al. "Removal of Mercury from Solutions of
Alkali Hydroxides" (abstract). Chemical Abstracts 74:55756J (1971).
660 Friedman, M», et_ al_» "Sorption Behavior of Mercuric and Meth-
ylmercuric Salts on Wool." Presented at the 161st ACS National
Meeting, Los Angeles, California, March 28 - April 2, 19710
67» National Aeronautics and Space Administration,, U. S. patent
no0 3,463,635.
65
-------
APPENDIX A
-------
PAINT BIOCIDE GUIDE
From: Paint and Varnish Production,
March 1971, reprinted by
permission .
BRAND NAME
Advacide ATO
Advacide N-628
Advacide PMA 18
Advacide PMO 11
Advacide TMP
Advacide 6O
Advacide 340-A
Bairskin A
bioMet TBTF
bioMet TBTO
Busan 11-M1
Busan 74
CB-111
CNC
Cosan P
Cosan PCMC
Cosan PMA-3O
Cosan PMA-1OO (Bulk)
Cosan PMA-1OO-WSB
Cosan PMO-3O
Cosan S
Cosan 171-S
Cosan 34O
Cosan 635-W
Cytox 2O13
Cytox 216O
Cytox 3522
Cvtox 381O
Diaphene
Dioxin
Dowicide A Antimicrobial Agent
Dowicide G Antimicrobial Aqent
Dowicide 6 Antimicrobial Agent
Dowicide 7 Antimicrobial Aqent
Dowicil 1OO Antimicrobial Agent
Dowicil S13 Antimicrobial Agent
DS 2787 Industrial Biocide
DS 4O18 Industrial Biocide
Fundex CQ
Fundex DO
Fundex DT
Fundex TMT
Fundex TO
Fundex ZO
Funqitrol 11
G4 Tech.
G4-40-Tech.
Giv-Gard ENS
Keycide X-10
Merbac-35
Mersolite 88
Mersolite 9O
Mersolite 430
Mersolite 810
Mersolite 830
Metasol D3T
Metasol TK-10O
Metasol 57
Nildew AC3O
Nildew CMK
Nildew Dl
Nildew D2
Nildew OL3O
GENERIC DESIGNATION
tributyltin oxide
tri-alkyl organotin
phenyl mercury acetate liquid
phenyl mercury oleate liquid
(n-trichloromethyl ) thio phthalimide
phenyl mercury acetate powder
tributyltin oxide
methylethylketoxime
tributyltin fluoride
bis tributyltin oxide
modified barium metaborate
proprietary
copper borate
copper naph. 8%
N-trichloromethyl thiophthalimide
parachlorometacresol
phenyl mercury acetate solubilized
phenyl mercury acetate
phenyl mercury acetate in water soluble bags
phenyl mercury oleate
3, 5-dimethyltetrahydro 1, 3, 5,
2H-thiadiazine-2-thione
phenyl mercury 2-ethylhexylmaleate
organotin/organomercurial
complexed alkyl amine
dodecylquanidine hydrochloride
dodecylquanidine acetate
methylenebisthiocyanate
chloroethylene bisthiocyanate
3,4*5 tribromosalicylanilide
dimethoxane
0-phenylphenol , sodium salt, tetrahydrate
sodium pentachlorophenate
2, 3, 4j 6-tetrachlorophenol
pentachlorophenol
l-(3-chloroallyl)-3, 5, 7, triaza-
1-azonia-adamantane chloride
2, 3, 5, 6-tetrachloro-4-(methyl sulfonyl)-
pyridine
tetrachloroi soph thalonit rile
3, 4, 5-trichloro-2 , 6-dicvanopyridine
copper 8-quinolinalate
m-dodecvlquanidine acetate
3, 5 dimethyl tetrahydro 1,3, 5
2H-thiadiazine 2-thione
n-trichloromethyl thiophthalimide
tributyltin oxide
zinc dimethyl dithiocarbamate
N( trichloromethylthio) phthalimide
dichlorophene
dichlorophene solution
bromonitrostyrene
stabilized form of tributyltin oxide
benzyl bromoacetate
phenyl mercuric acetate
phenyl mercuric borate
phenyl mercuric oleate
phenyl mercuric acetate
phenyl mercuric acetate
tetrahydro-3, 5 dimethyl-2H-l , 3, 5-
thiadiazine-2-thione
2-(4-thiazolylj^ benzimidazole
phenyl mercuric propionate
phenyl mercuric acetate
p-chloro-m-cresol
acetal
acetal
phenyl mercuric oleate
MANUFACTURER
5
5
5
5
5
5
•5
3
12
12
4
4
10
20
6
6
6
6
6
6
6
6
6
6
2
2
2
2
J7
9
8
8
8
R
8
ft
7
7
1
1
1
1
1
1
21
9
9
9
25
13
?A
?4
?,4
2.4
?A
n
13
13
14
14
14
14
14
FUNGICIDE
•
•
•
•
•
•
•
•
«
•
•
•
•
•
•
•
•
•
9
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
PRESERVATIVE
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
«
•
•
•
*
•
•
•
•
MERCURIAL
•
•
•
•
•
•
•
•
•
•
•
•
NON-MERCURIAL
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
FOR OIL BASE PAINTS
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
FOR EMULSION PAINTS
•
•
•
•
•
•
•
•
•
•
•
••
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
68
-------
BRAND NAME
Omacide-2
Omacide-12C
Omacide-645
Omadine solution (4O% sodium)
Onyxide 172
Organoarse
Organoarse
Organoarse
PMA-18
PMO-1O
Proxel CRL
RCI
RCI 49-135, 136
RCI 49-162
Salicylanilide
Sherstat SLN
Sherstat TBS
Super Ad-It
Troysan CMP Acetate
Troysan PMA-10SEP
Troysan PMA-20SEP
Troysan PMA-3O
Troysan PMA-1OO
Trovsan PMO-3O
Troysan 142
Trovsan 174
Vancide PA
Vancide TH
Vancide 51Z
Vancide 89
ZB-112, ZB-237
ZB-325
ZNC
GENERIC DESIGNATION
sodium pyridinethione-N-oxide plus
sodium tetra borate pentahydrate
sodium pyridinethione-N-oxide plus
sodium chromate
zinc pyridinethione-N-oxide and a
polybrominated salicyLanilide
40% solution of sodium pyridinethione-N-
oxide
alkyl dimethyl ethylbenzyl ammonium
cyclohexylsulf amate
phenarsazine chloride
phenarsazine dimethyl dithiocarbamate
triphenarsazine chloride
phenyl mercury acetate
phenyl mercury oleate
benzisothiazolone
O-phenylphenol
O-benzyl P-chlorophenol
pentachlorophenol
salicylanilide
Salicylanilide
3, 4't 5-tribromosalicylanilide
phenyl mercury dodecenyl succinate
chlormethoxypropy I/mercury compound
phenyl mercury compound
phenvl mercury compound
phenyl mercury compound
phenyl mercury compound
phenyl mercury compound
heterocyclic sulfur compound
aminoethanol compound
ethene type
triazine type
dithiocarbamate type
substituted hydrqphthalimide
zinc borate
zinc borate
zinc naph.
lANUFACTURER
15
15
15
15
16
1
1
1
21
21
11
18
18
18
17
19
19
21
22
22
22
22
22
22
22
22
23
23
23
23
10
10
20
UNGICIDE
•
•
•
•
•
RESERVATIVE
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
lERCURIAL
•
•
•
•
•
•
ION-MERCURIAL
•
•
•
•
•
•
•
•
•
•
*
*
•
•
•
•
•
*
•
I/)
<
(X
to
U5
<
CD
8
ft
o
•
•
•
•
•
•
•
•
•
OR EMULSION PAINTS
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
ACETO CHEMICAL CO., INC. 1O.
126-O2 Northern Blvd.
Flushing, N.Y. 11368
AMERICAN CYANAMID CO. H-
Industrial Chemical Division
1937 West Main St.
Stamford, Conn. O6904 12-
BAIRD CHEMICAL INDUSTRIES, INC.
22-1O Route 208
Fair Lawn, N.J. 07410 13-
BUCKMAN LABORATORIES, DC.
1256 North McLean Blvd.
Memphis, Tenn. 381O8 14-
CINCINNATI MILACRON CHEMICALS, INC.
5OO Jersey Ave.
New Brunswick, N.J. 089O3 I5-
COSAN CHEMICAL CORP.
481 River Road
Clifton, N.J. O7O14 16-
DIAMOND SHAMROCK CORP.
3OO Union Commerce Blvd.
Cleveland, Ohio 44115 17-
DOW CHEMICAL CO.
Midland, Mich. 48640
GIVAUDAN CORP. 18-
321 West 44th St.
New York, N.Y. 1OO36
HUMPHREY CHEMICAL CORP.
P.O. Box 2
Edgewater Arsenal, Md. 21O1O
ICI AMERICA, INC.
151 South St
Stamford, Conn. O6904
M & T CHEMICALS, INC.
Subsidiary of American Can Co.
Rahway, N.J. 07O65
MERCK & CO., INC.
Merck Chemical Division
Rahway, N.J. 07O65
NAFTONE, INC.
425 Park Ave.
New York, N.Y. 10O22
OLIN CHEMICALS
12O Long Ridge Rd.
Stamford, Conn. O6904
ONYX CHEMICAL CO.
190 Warren St.
Jersey City, N.J. 073O2
PFISTER CHEMICAL WORKS, INC.
Linden Ave.
Ridgefield, N.J. 07657
REICHHOLD CHEMICALS, INC.
RCI Building
White Plains, N.Y. 1O6O2
SHERWIN-WILLIAMS CHEMICALS
Division of Sherwin-Williams Co.
116 St. Clair Ave. Northwest
P.O. Box 5638
Cleveland, Ohio 441O1
STRESEN-REUTER INTERNATIONAL,
SUBSIDIARY INTERNATIONAL MINERALS
& CHEMICALS CORP.
400 West Roosevelt Ave.
Bensenville, 111. 6O1O6
TENNECO CHEMICALS, INC.
Intermediates Division
P.O. Box 2
Piscataway, N.J. O8854
TROY CHEMICAL CORP.
One Avenue L
Newark, N.J. 07105
R.T. VANDERBILT CO., INC.
23O Park Ave.
New York, N.Y. 10017
VENTRON CORP.
Congress Street
Beverly, Mass. O1915
WITCO CHEMICAL CORP.
Organics Division
277 Park Ave.
New York, N.Y. 10017
69
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Agricultural Chemicals
The following tables represent some of the current technical and
quantitative data available on seed treatment fungicides.
Table 1. Seed Treatment Fungicides Used on Cottonseed
Common or
Trade Name
Form
Applied
Chemical Composition
Mercurial fungicides;
Ceresan M
Ceresan L
Panogen 15
PMA
Non-Mercurial fungicides:
Busan 72
captan
chloroneb
chlorothalonil-Dexon
Terracoat L21
thiram
carboxin
Slurry 7. 7% N- (ethylmercury)-p_-
toluenesulfonanilide
Liquid 2.89% methylmercury 2,3-dihydroxy-
propylmercaptide and 0.62% methyl-
mercury acetate
Liquid 2.2% cyano(methylmercuri)-
guanidine
Liquid 7% phenylmercury acetate
Liquid 60% 2-(thiocyanomethylthio)-
benzothiazole
Slurry 75% N-((trichloromethyl)thio)-4-
cyclohexene-1,2-dicarboximide
Slurry 65% l,4-dichloro-2,5-dimethoxy-
benzene
Slurry 40% tetrachloroisophthalonitrile
and 32% sodium-g- (dimethylamino) -
benzene-diazosulfonate
Liquid 23.2% pentachloronitrobenzene and
11.3% 5-ethoxy-3-trichloromethyl-
1,2,4-thiadiazole
Slurry 70% bis(dimethylthiocarbamoyl)-
disulfide
Slurry 75% 5,6-dihydro-2-methyl-l,4-
oxathiin-3-carboxanilide
From: C. D0 Ranney, "Effective Substitutes for Alkyl Mercury Seed
Treatments for Cottonseed," Plant Disease Reporter, March 1971.
70
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Table 2. Comparative Amounts of Active Ingredients Required for Treatment
Non-Mercurials
Common Product
Name Name
Thiram
C apt an
Maneb
PCNB + Terrazole
Carboxin
-
"Arasan" 75
"Captan" 75
"Orthocide" 75
"Manzate"
"Dithane"
"Terra-Coat" L-205
(under development)
"Vitavax"
"Busan" 72
Manufacturer
Du Pont
Stauffer
Chevron
Du Pont
Rohm & Haas
Olin
UniRoyal
Buckman Lab .
Crop
Cotton
Small
Grain
Flax
Small
Grain
Flax
Cotton
Small
Grain
Cotton
Small
Grain
Ounces
Active
per bu.
or cwt . *
2.25 cwt.
1.0 bu.
1.5 bu.
Same
Same
1.5 bu
2.0 bu.
4.8 bu.
.6 bu.
6.0 bu.
2.25 bu.
2.1 bu.
Ounces
Active
"Ceresan" L
(Mercurial)*
.105
.0175
.O525
.0175
.O525
.105
.0175
.105
.0175
.105
* At Average Rate of Application.
From: Dr. T. C. Ryker (Du Pont Company), private communication,
May 18, 1971.
Seed Treatment
None
Mercurials
Nonmercurials
Mercurials + chloroneb
Nonmercurials + chloroneb
Percent Seedling Survival
From: C. D. Ranney, Plant Disease Reporter, March 1971.
Figure 1. Pictorial Summary of Data from Table 4
71
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Table 3. Effectiveness and Costs of Wheat Seed Fungicides
Wheat Seed
Fungicide
methyl mercury
phenyl mercury
thiram
maneb
c apt an
c apt an HCB
Vitavax
More Plants
Per 100 Kernels
12
6
14
14
16
16
12
Stinking Smut
(bunt) Control*
B
B
S
S
MS
S
S
Cost Treat
Bushel**
10£
8
15
20
20
15
40
*B = best, S = satisfactory, MS = satisfactory if bunt spores are
not on the seed.
**Maneb and captan may cost less in large quantities.
From: Claude L. King (Kansas State University), "Mercuries Gone —
What for Seed Treatment?"
Table 4. Summary of Regional Cottonseed Treatment Tests
1968 - 1970
Seed Treatment
Number of tests*
Check (no treatment)
Ceresan M
Panogen 15
Ceresan L
Ceresan L + chloroneb
Busan 72
Busan 72 + chloroneb
chlorothalonil - Dexon
chlorothalonil - Dexon + chloroneb
Terracoat L21
* Conducted in the Cotton Belt by
From: C. D. Ranney, Plant Disease
Percent
1968
14
34.0
48.1
45.1
47.4
53.8
46.3
--
49.7
54.2
52.3
the Cotton
Reporter,
Seedling
1969
21
26.4
38.4
36.9
39.3
46.4
38.8
44.2
41.7
44.2
46.7
Survival
1970
.19
43.4
55.4
--
46.7
—
52.1
59.6
--
64.1
57.8
Disease Council.
March 1971
.
72
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APPENDIX B
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74
-------
MERCURY
100%
FLUORESCENT LAMP PLANT NO. 1
73%
Finished Lamps
7%
Shrinkage
Lamps
6%
Exhaust
Tubes
Sanitary
Landfill
Sold to
Glass Co.
Exhaust
Pump
Sludge
6%
Losses
MERCURY
100%
FLUORESCENT LAMP PLANT NO. 2
79%
Finished
Lamps
5%
Shrinkage
Lamps
Sanitary
Landfill
18%
Exhaust
Tubes
4%
Exhaust
Pump
Sludge
1%
Losses
75
-------
HIGH-INTENSITY DISCHARGE LAMP PLANT
MERCURY
100%
89%^
3%.
2%.
Finished
Lamps
Shrinkage
Lamps
Exhaust
Tubes
Exhaust
Pump
Sludge
Losses
Sanitary
Landfill
Sanitary
Landfill
76
-------
1 1 Accession Number
w
A 1 Subject Field & Group
05G
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
I- Organization
L^fJ* hr \f\^H *~*y *J ^" *^* *•'*•** • -^ **V-> • • ^*«»»H«»»*. ••< JL. -L. V
Environmental Systems Division
T/t/e
INDUSTRIAL WASTE STUDY — MERCURY-USING INDUSTRIES
Shilesky, D. M.
Krause, K0W.
EPA9 OWP - Project No. 805/25-18000 HIP
2LJ
Woto
22
Citation
23
CescWptors (Starred First)
•Abatement, industrial Waste Water Treatment, *Heavy Metal, *Waste Water
Disposal, Effluents, Liquid Wastes, Waste Disposal, Wastes
Water Pollution Sources
25
Identifiers (Starred First)
*Water Pollution Sources, *Waste Treatment, *Heavy Metal, Chemical Precipitation,
Activated Carbon, Pollution Abatement, Landfills
27
Abstract This study discusses information obtained from a literature survey, mail
survey, telephone contact phase, and field trip pertaining to industrial wastes
of mercury-using industries. The main topics presented for each industrial group
are: (1) uses of mercury; (2) reasons for industry's use of mercury; (3) alter-
natives to use of mercury in the industry; and (4) best available level of treat-
ment and control. Research needs are also recommended for future studies. In
general, it was found that under present technology mercury cannot be fully replaced
in dentistry, the electrical industry (lamps, batteries), production of chemicals
(Pharmaceuticals, laboratory reagents), catalysis, and industrial and control instru-
mentation. Substitution is technologically possible but probably not warranted
because of minimal hazard from mercury use in switches and in some industrial and
control instrumentation. Substitution is possible and highly desirable (in the
absence of fully effective treatment and control methods) in the chlor-alkali and
plastics industries. Use if mercury has come or is coming to an end in agriculture,
paints, and pulp and paper production. The best present and proposed treatment and
control methods can reduce typical mercury concentrations in industrial waste waters
to levels of 1 to 5 ppb. However, very few facilities control their mercury dis-
charges to this extent.
(Shilesky . Litton)
Abstractor
D.
M,
Shilesky
Institution
Litton
Systems.
Inc.
Env i r onmenta 1
Systems
Div
•
WR 102 (REV. JULY 1969)
WRSI C
U. S. GOVERNMENT PRINTING OFFICE -1 972 —51 It-11(5 (It)
SEND, WITH COPY OF DOCUMENT, TO: WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON, D. C. 20240
OPO: 1S70 - 407 -881
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