United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Cincinnati OH 45268
EPA 600 7-79-145
August 1979
Research and Development
Environmental
Considerations of
Selected Energy-
Conserving
Manufacturing
Process Options
Volume XVIII.
Particulates
Summary Report
Interagency
Energy/Environment
R&D Program Report
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide range of energy-related environ-
mental issues.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/7-79-145
August 1979
ENVIRONMENTAL CONSIDERATIONS OF SELECTED
ENERGY-CONSERVING MANUFACTURING PROCESS OPTIONS
Volume XVIII. Particulates Summary Report
by
Arthur D. Little, Inc.
Cambridge, Massachusetts 02140
Contract No. 68-03-2198
Project Officer
Herbert S. Skovronek
Power Technology and Conservation Branch
Industrial Environmental Research Laboratory
Cincinnati, Ohio 45268
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CTNCTNNATT. OHTO 45268
For tale by the Superintendent of Document*, U.S. Government
Printing Office, Washington, D.C. 20402
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DISCLAIMER
This report has been reviewed by the Industrial Environmental Research
Laboratory-Cincinnati, U.S. Environmental Protection Agency, and approved for
publication. Approval does not signify that the contents necessarily reflect
the views and policies of the U.S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or
recommendation for use.
ii
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FOREWORD
When energy and material resources are extracted, processed, con-
verted, and used, the related pollutional impacts on our environment,
and even on our health, often require that new and increasingly more
efficient pollution control methods be used. The Industrial Environ-
mental Research Laboratory - Cincinnati (TERL-Ci) assists in developing
and demonstrating new and improved methodologies that will meet these
needs both efficiently and economically.
This report summarizes information on particulates from a study
of 13 energy-intensive industries. If implemented over the coming 10
to 15 years, these processes and practices could result in more effec-
tive utilization of energy resources. The study was carried out to
assess the potential environmental/energy impacts of such changes and
the adequacy of existing control technology in order to identify po-
tential conflicts with environmental regulations and to alert the
Agency to areas where its activities and policies could influence the
future choice of alternatives.
The results will be used by the EPA's Office of Research and De-
velopment to define those areas where existing pollution control tech-
nology suffices, where current and anticipated programs adequately ad-
dress the areas identified by the contractor, and where selected pro-
gram reorientation seems necessary.
Specific data will also be of considerable value to individual
researchers as industry background and in decision-making concerning
project selection and direction.
The Power Technology and Conservation Branch of the Energy Sys-
tems-Environmental Control Division should be contacted for additional
information on the program.
David G. Stephan
Director
Industrial Environmental Research Laboratory
Cincinnati
iii
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ABSTRACT
Under EPA Contract No. 68-03-2198, Arthur D. Little, Inc.
undertook a study of the "Environmental Considerations of
Selected Energy-Conserving Manufacturing Process Options."
Some 80 industrial process options were examined in 13 industrial
sectors. Results were published in 15 volumes, including a
summary, industry prioritization report, and 13 industry
oriented reports (EPA-600/7-76-034 a through o).
This present report summarizes the information regarding
nitrogen oxide pollutants in the 13 industry reports. Four
parallel reports treat sulfur oxides, particulates, solid
residues, and toxics/organics. All of these pollutant oriented
reports are intended to be closely used with the original 15
reports.
iv
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CONTENTS
Foreword
Abstract iv
Tables vi
English-Metric (SI) Conversion Factors viii
1. INTRODUCTION 1
BACKGROUND AND PURPOSE 1
APPROACH 2
2. FINDINGS AND R&D OVERVIEW 5
FINDINGS 5
R&D AREAS 15
3. PROCESS AND POTENTIAL PARTICULATE EMISSIONS 23
BASES OF CALCULATIONS 23
PARTICULATE CONTROL METHODS 24
IRON AND STEEL INDUSTRY 26
PETROLEUM REFINING INDUSTRY 33
PULP AND PAPER INDUSTRY 37
OLEFIN INDUSTRY 44
ALUMINA AND ALUMINUM INDUSTRY 51
CEMENT INDUSTRY 59
GLASS INDUSTRY 63
PHOSPHORUS/PHOSPHORIC ACID INDUSTRY 70
COPPER INDUSTRY 77
AMMONIA INDUSTRY 84
CHLOR-ALKALI INDUSTRY 87
FERTILIZER INDUSTRY 91
TEXTILE INDUSTRY 96
REFERENCES 100
TECHNICAL REPORT DATA (includes abstract) 101
v
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TABLES
Number Page
1 Projected U.S. Production in Industries Studied 4
2 Summary of Estimated Annual Particulate Emissions 6
3 Nationwide Emissions Estimates for Particulates (1974) 17
4 Estimated Increase in Controlled Particulate Emissions
1989-1974 Assuming Industry Expands Using Process
Types Indicated 18
5 Estimated Range in Controlled Particulate Emissions in
1989 for New Processes Likely to be Implemented 21
6 Estimated Particulate Emission Factors - Iron and Steel
Industry 27
7 Estimated Particulate Emissions - Iron and Steel Industry 28
8 Estimated Particulate Emission Factors - Petroleum
Refining Industry 38
9 Estimated Particulate Emissions - Petroleum Refining
Industry 39
10 Estimated Particulate Emission Factors - Pulp and Paper
Industry 43
11 Estimated Particulate Emissions - Pulp and Paper Industry 45
12 Estimated Particulate Emission Factors - Olefin Industry 49
13 Controlled Estimated Particulate Emissions - Olefin Industry 50
14 Estimated Controlled Particulate Emission Factors - Alumina
and Aluminum Industry 56
15 Estimated Particulate Emissions - Alumina and Aluminum
Industry 57
16 Estimated Particulate Emission Factors - Cement Industry 64
17 Estimated Particulate Emissions - Cement Industry 65
18 Estimated Particulate Emission Factors - Glass Industry 67
19 Estimated Controlled Particulate Emissions - Glass Industry 71
vi
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TABLES (cont.)
Number Page
20 Estimated Particulate Emission Factors - Phosphoric Acid
Industry 75
21 Estimated Particulate Emissions - Phosphoric Acid Industry 76
22 Estimated Particulate Emission Factors - Primary Copper
Industry 82
23 Estimated Particulate Emissions - Copper Smelting 83
24 Estimated Controlled Particulate Emissions - Ammonia
Industry 85
25 Estimated Particulate Emissions - Chlor-Alkali Industry 90
26 Estimated Controlled Particulate Emissions - Fertilizer
Industry 94
27 Estimated Particulate Emissions - Textile Industry 99
LIST OF FIGURES
1 Particulate Control Device Performance Comparison 25
vn
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ENGLISH-METRIC (SI) CONVERSION FACTORS
To Convert From
To
2
Metre
Pascal
3
Metre
Joule
Pascal-second
Degree Celsius
Degree Kelvin
Metre
Metre /sec
3
Metre
2
Metre
Metre/sec
2
Metre /sec
Metre
Watt
Watt
Watt
Metre
Joule
Metre3
Metre
Metre
Metre
Pascal-second
Newton
Kilogram
Kilogram
Kilogram
Kilogram
Kilogram
Kilogram
Multiply By
4,046
101,325
0.1589
1,055
0.001
t° = (t° -32)/1.8
o o
0.3048
0.0004719
0.02831
0.09290
0.3048
0.00002580
0.003785
745.7
746.0
735.5
0.02540
3.60 x 106
1.000 x 10"3
1.000 x 10"6
0.00002540
1,609
0.1000
4.448
0.4536
0.02916
1,016
1,000
907.1
1,000
Acre
Atmosphere (normal)
Barrel (42 gal)
British Thermal Unit
Centipoise
Degree Fahrenheit
Degree Rankine
Foot
3
Foot /minute
3
Foot
Foot2
Foot/sec
2
Foot /hr
Gallon (U.S. liquid)
Horsepower (550 ft-lbf/sec)
Horsepower (electric)
Horsepower (metric)
Inch
Kilowatt-hour
Litre
Micron
Mil
Mile (U.S. statute)
Poise
Pound force (avdp)
Pound mass (avdp)
Ton (Assay)
Ton (long)
Ton (metric)
Ton (short)
Tonne
Source: American National Standards Institute, "Standard Metric Practice
Guide," March 15, 1973. (ANS72101-1973) (ASTM Designation E380-72)
viii
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SECTION I
INTRODUCTION
BACKGROUND AND PURPOSE
During 1975 and the first half of 1976, under EPA Contract No.
68-03-2198, Arthur D. Little, Inc., undertook a study of the "Environmental
Considerations of Selected Energy-Conserving Manufacturing Process Options"
in 13 energy-intensive industry sectors for the U.S. Environmental
Protection Agency (EPA). The results of these studies were published
in the following reports:
• Volume I — Industry Summary Report (EPA-600/7-76-034a)
• Volume II — Industry Priority Report (EPA-600/7-76-034b)
• Volume III — Iron and Steel Industry Report (EPA-600/7-76-034c)
• Volume IV — Petroleum Refining Industry Report (EPA-600/7-76-034d)
• Volume V -- Pulp and Paper Industry Report (EPA-600/7-76-034e)
• Volume VI — Olefins Industry Report (EPA-600/7-76-034f)
• Volume VII — Ammonia Industry Report (EPA-600/7-76-034g)
• Volume VIII — Alumina/Aluminum Industry Report (EPA-600/7-76-034h)
• Volume IX — Textile Industry Report (EPA-600/7-76-034i)
• Volume X — Cement Industry Report (EPA-600/7-76-034J)
• Volume XI — Glass Industry Report (EPA-600/7-76-034k)
• Volume XII -- Chlor-Alkali Industry Report (EPA-600/7-76-0341)
• Volume XIII — Phosphorus/Phosphoric Acid Industry Report
(EPA-600/7-76-034m)
• Volume XIV — Copper Industry Report (EPA-600/7-76-034n)
• Volume XV — Fertilizer Industry Report (EPA-600/7-76-034o)
In the course of this study, we examined some 80 industrial process
options focussing on:
• Identification of any major sources of pollutants (air, water,
and solid residues) expected from the processes,
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• Development of estimated capital and operating costs for both
production and pollution control aspects of the processes,
• Estimation of the types and amounts of energy used in both
production and pollution control for the processes,
• Assessment of the economic viability and likelihood of
implementation of those alternative process options being
studied,
• Identification of areas where EPA's activities and policies
could influence the future choice of alternatives, and
• Identification of research and development areas in both
process and pollution control technology.
Because of the industry orientation of the sutdy, the 15 volumes
of which consisted of 1,700 pages, we felt we needed to summarize
pollutant-specific information across all the 13 sectors studied. Five
such pollutants were identified to be of particular interest:
• Nitrogen oxide (NO ) emissions,
X
• Sulfur oxide (SO ) emissions,
X
• Fine particulate emissions,
• Solid residues, and
• Organic and/or toxic pollutants.
A summary pollutant report in each of these areas has been prepared.
Although some estimates and extrapolations on pollutants have been
attempted where the information was readily available, in general, we
have not attempted to go beyond the 15 original reports.
APPROACH
These summary pollutant reports are intended to be used closely
with the original 15 reports. Generally, information, such as detailed
descriptions of the processes, has not been duplicated in these pollutant
reports. Sections of the previous 15 reports where this information can
be found have been extensively referenced by volume number and page num-
ber (e.g., Vol. VII, page 20, refers to page 20 of the Ammonia Industry
Report).
In Section 2 of this report (Findings and R&D Overview), summary
information on generic, cross-industry problems that emerged and sug-
gestions for R&D work in the areas of both pollution control technology
and process technology are presented. In Section 3 of this report, the
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availability and applicability of particulate pollution control techno-
logy are presented, and fine particulate emissions and controls reported
in our previous study are reviewed. All emissions are estimated, unless
specifically referenced, since we believe that actual data do not exist
for many of the processes described.
To give the reader a sense of the size of the industries for which
the pollution problems covered in these summary pollutant reports are con-
sidered, Table 1 lists these industries, their total production in 1974
(the base case year for the study), and their projected incremental
production in 1989, 15 years hence. This information can be used to
calculate readily a gross estimate of the pollutant load (e.g., particu-
lates) which can be expected in 1989, assuming that the specific process
accounts for all incremental production in that year relative to 1974.
Similarly, expected total emissions can also be determined.
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TABLE 1. PROJECTED U.S. PRODUCTION IN INDUSTRIES STUDIED
Commodity
Total U.S.
projection
in 1974
(10 tons*)
Projected
rate of
growth
(%/yr)
Total
projected
production
in 1989
(10b tons)
Increase in
annual
production
in 1989 over
that,of 1974
(10b tons)
Alumina 7.7
Aluminum 5.0
Ammonia 9.2
Cement 79.0
Chlorine 11.0
Coke 62.0
Copper 1.6
Fertilizers (HNO ) 8.2
Glass (flat) 29.0
Iron 100.0
Olefins (ethylene) 13.0
Petroleum 740.0**
Pulp (Kraft) 16.0
Pulp (newsprint) 3.9
Phosphoric Acid
(detergent grade) 1.4
Phosphoric Acid
(wet acid grade) 9.0
Steel 133.0
Textiles (knit) 0.32
Textiles (woven) 2.1
2.
5.
6.0
6.0
6.0
,0
.0
2.5
3.5
4.0
2.5
2.5
8.0
1.5
5.0
2.5
2.5
2.5
2.5
2.2
2.2
18.5
12.0
22.0
106.3
22.9
89.8
2.7
14.8
42.0
144.8
41.2
925.0***
33.0
5.6
2.03
13.0
193.0
0.44
2.91
10.8
7.8
12.8
27.3
11.9
27.8
1.1
6.6
13.0
44.8
28.2
185.0****
17.3
1.7
0.63
4.0
60.0
0.12
0.81
*A11 tons referred to in these reports are net tons, unless otherwise
indicated.
**Approximate equivalent of 30 quads (1 quad is equal to 10
***Approxitnate equivalent of 37.5 quads.
****Approximate equivalent of 7.5 quads.
15
Btu).
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SECTION 2
FINDINGS AND R&D OVERVIEW
FINDINGS
The thirteen industries addressed in the original study have parti-
culate pollution problems which are affected by the process changes and,
therefore, are covered in this report. Table 2 summarizes the estimated
particulate emissions from both the base case processes and process
alternatives for these industries.
The emission factors shown in the table include both process and
power boiler emissions. These factors do not include fugitive* (area)
emissions, but are limited to source emissions. Emissions from the power
boiler were generally not considered in the original study; however,
they have been included here to make comparisons of emissions from the
baseline and alternative processes more comprehensive. Both on-site
power boilers for steam and electricity generation and off-site utility
power boilers for electricity generation are considered. The total
particulate emission factors for processes with pollution control vary
from about 0.2 Ib/ton to 100 Ib/ton of product.
In some processes, such as production of aluminum in electrolytic
cells using the Hall-Heroult process, it may not be possible to completely
enclose the emission source. In such cases, emissions escaping the col-
lection device are significant and generally exceed controlled emissions.
Therefore, the emission factor for the Hall-Heroult process of the
aluminum industry is high.
Estimated particulate emissions based on best available control
technology for 1974 from the processes studied are shown in Table 2.
These controlled emissions are based on estimated emission factors and
the 1974 production shown in Table 1. The emission factors are estimated
(see Section 3) based on engineering judgments unless referenced! The
emissions in Table 2 are from processes studied and therefore do not
represent total industry emissions. Industries responsible for the
largest quantities of particulate emissions are steel, aluminum, and
petroleum refining. Industries having more moderate emissions include
pulp and paper, alumina, and cement.
Fugitive emissions are defined as area emissions. Emissions escaping
the hoods are not included in fugitive emissions as these are source
emissions and not area emissions.
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TABLE 2. SUMMARY OF ESTIMATED ANNUAL PARTICULATE EMISSIONS
Commodity Process
Controlled
particulate
emissions
in 1974 from
base case process
(106 lb/vr)
Controlled
particulate
emissions
(1989-1974)3
(10° lb/yr)
Change in
particulate
emissions from
base case.
(in 1989)
(10b lb/yr)
Petroleum Base case:
East Coast refinery 339.0
• Direct combustion of
asphalt in process
heaters and boilers —
• Flexicoking —
Base case:
Gulf Coast refinery 354.0
• On-site electric power
by combustion of vacuum
bottoms
Base case: (
West Coast refinery 420.0
• Hydrocracking of heavy
bottoms —
• High-purity hydrogen
via partial oxidation
of asphalt —
84.8
114.8
85.
88.5
88.5
105.0
112.5
105.0
+ 30
.7
0
7.5
(continued)
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TABLE 2. (continued)
Commodity Process
Controlled
particulate
emissions
in 1974 from
base case process
(1(T Ib/yr)
Controlled
particulate
emissions
(1989-1974)a
(10 Ib/yr)
Change in
particulate
emissions from
base case
(in 1989)b
(10° Ib/yr)
Alumina Base case:
Bayer process
• Hydrochloric acid
ion exchange
• Nitric acid
ion exchange
• Toth alumina
Aluminum Base case:
Hall-Heroult
(current practice, C.P.)
• Hall-Heroult (new)
• Alcoa chloride
• Refractory hard
metal cathode
Base case:
Bayer with Hall-
Heroult (C.P.)
59.3
242-487
356-601
83.2
47.5
N.A.
N.A.
338.4-681.8
130.2
N.A.
315.7-660.8
499-842
- 35.7
N.A.
N.A.
-208.2 to -551.6
N.A.
- 22.7 to -21.0
(continued)
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TABLE 2. (continued)
Commodity Process
Controlled
particulate
emissions
in 1974 from
base case process
(10b Ib/yr)
Controlled
particulate
emissions
(1989-1974)a
(10 Ib/yr)
Change in
particulate
emissions from
base case
(in 1989)b
(10 Ib/yr)
Aluminum (cont)
Kraft pulp
oo
Newsprint
pulp
Clay chlorination
(toth alumina) and
aloca chloride
Base case:
Kraft pulping
• Alkaline oxygen
pulping
• Rapson effluent-
free Kraft pulping
Base case:
Refiner mechanical
pulp (RMP)
• Thermo-mechanical
pulp (IMP)
• De-inking of old
news for newsprint
manufacture
57.6
7.8
N.A.
62.3
62.3
59.0
3.4
2.4
1.0
N.A.
- 3.3
- 1.0
- 2.4
(continued)
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TABLE 2. (continued)
Commodity Process
Flat glass Base case:
Regenerative furnace
• Coal gasification
• Direct coal firing
• Coal-fired hot gas
generation
• Electric melting
Controlled
particulate
emissions
in 1974 from
base case process
(10b Ib/yr)
3.5
—
—
—
—
Controlled
particulate
emissions
(1989-1974)a
(10b Ib/vr)
1.6
^ 1.6
> 1.6
N.A.
'v/lO.?
Change in
particulate
emissions from
base case
(in 1989)b
(10b Ib/yr)
—
•x, 0
N.A.
N.A.
t 9.1
Copper
• Batch preheat with
natural gas firing
Base case:
Conventional smelting
• Outokumpu flash smelting
• Noranda
• Mitsubishi
• Arbiter
1. 3
1.6
.9
3.8
.9
.9
5.7
+ 2.9
0
0
+ 4.8
(continued)
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TABLE 2. (continued)
Commodity Process
Chlorine, NaOH Base case:
Graphite-anode
diaphragm cell
• Dimensionally stable
anodes
• Expandable DSA
Controlled
p articulate
emissions
in 1974 from
base case process
(10b Ib/yr)
39.6
—
—
• Polymer modified asbestor
• Polymer membrane
• Ion exchange membrane
• Mercury cell
—
—
—
Controlled
particulate
emissions
(1989-1974)3
(106 Ib/yr)
42.8
41.1
37,0
37.6
37.6
37.6
46,5
Change in
particulate
emissions from
base case,
(in 1989)
(10 Ib/yr)
- 1.7
- 5.8
- 5.2
- 5.2
- 5.2
+ 3.7
Steel Base case:
No off—gas recovery 69.2
• Off-gas recovery
Blast furnace Base case:
hot metal Blast furnace 150.0
• Blast furnace with
external desulfurization
31.2
15.6
67.5
81.0
-15.6
+13.5
(continued)
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TABLE 2. (continued)
Commodity Process
Controlled
particulate
emissions
in 1974 from
base case process
(10b Ib/yr)
Controlled
particulate
emissions
(1989-1974)
(10 Ib/yr)
Change in
particulate
emissions from
base case.
(in 1989)
(10b Ib/yr)
Coke Base case:
Steel
(integrated)
Wet quenching of coke
Dry quenching of coke
Base case:
Steelmaking: coke oven,
blast furnace BOP route
• Direct reduction,
EAF route
80.6
452.2
58.5
54.0
204.0
66.0
- 4.5
-138
Phosphoric
acid (detergent
grade) Base case:
Electric furnace
• Chemical cleanup of
wet-process acid
• Solvent extraction
of wet-process acid
15.3
6.9
1.7
5.4
- 5.2
- 1.5
(continued)
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TABLE 2. (continued)
Commodity
Fertilizers
(nitric acid)
Process
Base case:
No NO control
X
• Catalytic reduction
• Molecular sieve
• Grand Paroisse
• CDL/Vitak
• Masar
Controlled
particulate
emissions
in 1974 from
base case process
(10b Ib/yr)
- .08
—
—
—
—
—
Controlled
particulate
emissions
(1989-1974)a
(10° Ib/yr)
- .07
- .07
2.9
.07
7.7
13.9
Change in
particulate
emissions from
base case
(in 1989)
(10° Ib/yr)
__
0
+ 2.97
+ .14
+ 7.77
13.97
Fertilizers (mixed): converting fertilizer dryers (with baghouses) from natural gas to oil
Base case:
Natural gas
• Better equipment technique
with fuel oil
• Installing scrubbers
.11
< 0.08
< 0.08
< 0.16
0
+ .08
(continued)
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TABLE 2. (continued)
Commodity Process
Textiles Knit fabric:
• Base case:
Conventional aqueous
• Advanced aqueous
• Solvent processing
Woven fabric:
• Base case
• Advanced aqueous
Controlled
particulate
emissions
in 1974 from
base case process
(106 Ib/yr)
.17
—
2.5
—
Controlled
particulate
emissions
(1989-1974)
(106 Ib/yr)
0.06
0.07
0.03
0.98
0.46
Change in
particulate
emissions from
base case
(in 1989)
(10b Ib/yr)
+ .01
- .03
—
- .52
Based on incremental production from the year 1974 to 1989 derived from anticipated growth rates
(Table 1).
Assumes no retirement of existing facilities by 1989-
Q
National emission rates calculated as though the alternative process applies to all national
oil refinery production.
Change estimated from base case.
N.A. - not available.
"" approximately equal to
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The data in Table 2 represent mass data. The data are significantly
affected by changes in the emissions of large particulates because large
particulates contribute more to the mass than do small particulates.
Though such large particulates can be effectively controlled, in some
cases they do escape from the collection device. On the other hand,
although fine particulates contribute little to the mass of particulate
emissions, they may have a significant effect on health and visibility.
The particulate emissions in this report represent total emissions and
are not segregated according to the particle size because such information
cannot be estimated for new processes now in the development phase.
Estimated particulate emissions, based on projected incremental production
from 1974 to 1989, are also listed in Table 2. Maximum incremental
emissions are shown for both the base case and alternative processes,
assuming dedication of 100% of the incremental production rather than
a fraction to each process (base case and alternative).
Total real (albeit estimated) emissions from production of each
commodity in the year 1989 would be the sum of emissions from the base
case and all alternative processes, each in proportion to the fraction
of the total 1989 production for which it accounts. Obviously, it is
not possible to estimate or extrapolate most of these fractions with
any degree of confidence, nor is it necessarily valid to assume that
the 1974 base case process would continue to account for the same volume
of production as in 1974. In fact, certain newer, energy-conserving
processes may be preferred, not only for incremental production but
also for replacement production. Of course, it would be equally unrealistic
in most cases to predict that new technology, even with energy and
environmental advantages, would totally displace existing technology.
The estimated increase or decrease in emissions from each alternative
process in relation to its base case process is also shown in Table 2.
This change is based on incremental capacity. As the table shows, the
greatest potential for emission reduction exists in two industries:
(1) iron and steel, with direct reduction of iron ore and coke production
using dry quenching, and (2) aluminum, with the use of new prebake cells.
All of the process alternatives studied (Volumes III to XV) are
aimed at reduction in energy consumption, or conversion to more plentiful
fuel forms. Particulate emission is directly related to boiler fuel
consumption so fuel-conserving process changes will reduce particulate
emissions from boilers. However, conservation through conversion to more
plentiful fuel forms includes the switch from natural gas to either oil
or coal, from oil to coal, and then from natural gas to asphalt. Such
changes will cause increased emissions because boilers burning oil, coal,
or asphalt will inherently generate more particulates and will require
particulate control equipment. Even then, their controlled emissions
will generally exceed the uncontrolled emissions from boilers burning
natural gas.
14
-------
R&D AREAS
The following R&D areas have been identified as worthy of consideration
by industry, government agencies, or other institutions.
Particulate-Related Areas
• Improving fine particulate removal technology should include
control of those particulates resulting from metallic smokes
and sublimed substances such as mercury, arsenic, and zinc.
• The collection or control of process fugitive emissions is
a necessary R&D effort.
• Better quantitative knowledge of the environmental, health,
and ecological impacts of metallic smoke emissions is needed
to establish appropriate emission regulations.
Process-Related Areas
Iron and Steel—
• Quantitative measurements of fugitive and source emissions
from non-combustion BOP gas-collection systems are desirable.
Emissions are present during the transition periods at the
beginning and the end of a blow, when off-gases are not
collected for use as fuel, but their percent contribution
and nature are currently unknown.
• A comparison of available equipment for external desul-
furization should be made to determine the nature of
particulate emissions as a function of the desulfurizing
reagent used. Differences in character could contribute
to variations in case of removal.
• The quantification and characterization of particulate
emissions from rotary kilns (used for direct reduction)
are also desirable as a prelude to developing appropriate
control technology.
Petroleum Refining—
• Establish particulate emission factors for asphalt combustion.
Both uncontrolled and controlled emission factors should be
considered and applicable particulate control methods should
be defined, evaluated, and cost-analyzed.
15
-------
Pulp and Paper—
The de-inking of old newsprint for the manufacture of recycled
newsprint presents an opportunity to reduce particulate emissions,
as compared to emissions from other processes, because by the
very nature of the de-inking process, there are few particulate
emissions. Broader commercial application of this process
should be supported, because it could also reduce the amounts
of municipal solid wastes. However, the impact on "energy
from municipal waste" systems should not be ignored.
Aluminum—
Materials research should be conducted toward producing
titanium diboride cathodes capable of long operating life
in the Hall-Heroult cell. This development would produce
energy savings in the existing aluminum plants, thus
reducing particulate emissions at the fossil-fueled
electricity-generating plants, and could be a relatively
short-term objective.
Cement—
• Develop and implement a commercial-scale test program
on a rotary-kiln, cement-making facility equipped with
a flash-calciner to characterize particulate emissions.
Of particular interest would be the emissions from
operating with a bypass of a considerable amount of the
combustion gas to eliminate alkalies.
Glass—
• There is presently no proven process for treating emissions
from a glass-melting furnace economically. The particulates
present a difficult control problem. Research is needed in
this area in the immediate time frame for the current process,
and will be at least as necessary for the proposed coal-
based processes. The ability of a preheating system using
waste off-gases to "filter" fine particulates must also be
established.
Should U.S. industry expand using current (base case) technology,
Table 4 shows that estimated controlled particulate emissions in 1989
would increase by 0.86 to 1.2 x 10 Ib compared to particulate emissions
of 21.2 x 10 Ib from industrial processes and 68 x 10 Ib from electric
utilities in 1974 (Table 3). However, if all U.S. industry expanded by
implementing the technologies considered here that emitted the largest
amounts of particulates, Table 4 shows that the increase in particulate
16
-------
TABLE 3. NATIONWIDE EMISSIONS ESTIMATES
FOR PARTICULATES (1974)
Source Category
10 Ib/yr
of Total
Transportation
Stationary Fuel Combustion
2,600
6.4
Electric Utilities
Other
Industrial Processes
Solid Waste
Miscellaneous
Total
6,800
7,200
21,200
1,200
1,600
40,000
16.8
17.7
52.2
3.0
3.9
100.0
Source: National Air Quality and Emissions Trends Report, EPA,
Research Triangle Park, N.C., NTIS PB 263-922, 1978.
17
-------
TABLE 4. ESTIMATED INCREASE IN CONTROLLED
PARTICIPATE EMISSIONS 1989-1974
ASSUMING INDUSTRY EXPANDS USING
PROCESS TYPES INDICATED
(106 LB PARTICULATE/YR)
*
Commodity (vol no)
Steel (III)
Petroleum (IV)
Kraft pulp (V)
Newsprint Pulp (V)
Olefins (VI)
Ammonia (VII)
Alumina (VIII)
Aluminum (VIII)
Textiles-knit (IX)
Textiles-woven (IX)
Cement (X)
Flat Glass (XI)
Chlorine, NaOH (XII)
Phosphoric Acid (XIII)
Copper (XIV)
Fertilizers (HNO ) (XV)
Total
Base case
process
204
85a
62
3
14
3
83
338-682
.06
1
18
2
43
7
1
- .ib
864-1208
Using process with
largest potential
particulate
emissions
204
115a
62
3
23
9
83
338-682
.07
1
18
11
47
7
6
14
941-1285
Using process with
smallest potential
particulate
emissions
66
853
59
1
14
2
48
130
.03
.50
13
2
37
2
1
_ .!b
450
Volume number of industry report.
Assumes East Coast refinery model applied nationally
Credit for steam reaised: see text on fertilizers in Section 3
of this report.
18
-------
9
emissions in 1989 would be .94 to 1.3 x 10 Ib or some 10% higher than
using conventional technology. On the other hand, if industry expanded
by implementing the least particulate-emitting technology, particulate
emissions in 1989 are calculated to increase by .45 x 10 Ib or some
47-63% less than by conventional technology. If the national production
growth rate projections shown in Table 1 are accurate, then calculated
emissions will probably lie somewhere between these extremes, with
energy (Btu) saving processes with lower particulate emissions somewhat
balancing the switch from natural and fuel oil to coal. Thus, incentives
for the implementation of energy conserving technology can have a signi-
ficant effect on future particulate emissions in the industrial sector.
Examination of the last column in Table 2 shows that greatest reduction
compared to the base case processes in Ib of particulate emissions per
year can be achieved by selective implementation of new processes in:
• aluminum (Hall-Heroult (new); refractory hard metal cathodes)
• steelmaking (direct reduction,EAF route)
• alumina (hydrochloric acid ion exchange)
Process changes in some of the industries shown in Table 2 may be
implemented because of feed stock shortages (e.g., manufacture of olefins
from low-sulfur naphtha rather than higher sulfur gas oil), and fuel
switching (e.g., use of coal in cement making). In other cases, processes
may be developed for other reasons, such as development of a domestic
alumina industry based on indigenous kaolin clays. Such a process based
on using coal to the extent possible, would result in significantly
higher particulate emissions than a Bayer plant based on natural gas,
as described in the Alumina/Aluminum Industry report. Although the
estimated change in emissions listed in Table 2 was based on incremental
capacity from 1974 to 1989 only, in some cases an alternative process or
a process modification, may replace existing capacity. For example, in
the aluminum industry, refractory hard metal cathodes may be installed
in existing Hall-Heroult cells. The application of alternative processes
to existing plant capacity (i.e., retrofitting) will increase the potential
effect on particulate emissions, compared to the estimated effect shown
in Table 2. Further perspectives in each of these industry sectors
with descriptions of the processes can be obtained from the individual
industry sector reports (Volumes III through XV).
To give some perspective to the magnitude of particulate emissions,
Table 3 shows the industrial process category to be the largest emitter
of particulates.
Table 5 shows our estimate of the types of processes likely to be
installed in the time period up to 1989 with the related particulate
emissions from new plants calculated for the year 1989 assuming no retire-
ment of existing facilities. For example, a reading of the industry
reports shows that in the phosphoric acid manufacture incremental detergent
19
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grade acid capacity will be effected most probably by wet acid cleanup
processes. If such capacity is installed, anticipated annual particulate
emissions in 1989 would be 2 x 10 Ib particulate/year (Table 5) compared
to the 7 x 10 Ib particulate /year if conventional electric furnace
technology were employed. Similar judgments were made in other sectors
to arrive at total calculated annual emissions of .6 to ,7 x 10 Ib
particulates emitted in 1989 from new plant capacity installed in the
period 1974-1989.
20
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TABLE 5. ESTIMATED RANGE IN CONTROLLED PARTICULATE EMISSIONS
IN 1989 FOR NEW PROCESSES LIKELY TO BE IMPLEMENTED
Commodity
(vol no)
Steel (III)
Petroleum (IV)
Kraft pulp (V)
Newsprint
pulp (V)
Olefins (VI)
Ammonia (VII)
Alumina3 (VIII)
Likley types of
processes to be
implemented in
new plants
Coke oven, blast furnace, BOP
Hydrocracking, flexicoking, etc.
Kraft, Rapson, alkaline-oxygen
RMP, TMP, de-inking
Naphtha, gas oil
Heavy fuel oil, coal
Bayer, leaching domestic clays
Calculated range
in annual particulate
emissions for new
plant capacity-1989
(10b Ib/yr)
188°- 204
86 - 115d
59 - 62
1-3
19 - 23
2-9
48 - 83
Aluminum
(VIII)
Textiles, knit
(IX)
Textiles, woven
(IX)
Cement (X)
a
a
Hall-Heroult" (aluminum chloride)
Advanced aqueous, solvent
Advanced aqueous
Preheaters, coal firing, etc.
Flat glass (XI) Regenerative furnaces, preheaters,
electric furnaces
Chlor-alkali
(XII)
Phosphoric acid:
detergent grade
(XIII)
Dimensionally stable anodes, new
membranes
Wet acid cleanup
Copper (XIV) Oxygen or flash processes
Fertilizers-
nitric acid (XV) Various NO control technologies
TOTAL
130
.03
.50
13
2
38
2
1
130
.07
.50
18
11
41
2
4
-.07 - 14
589 - 720
Volume number of industry report.
A significant fraction of the incremental U.S. demand is expected to
be imported.
In addition, electric furnaces are expected to be installed based at
least partially on scrap iron and steel.
(continued)
21
-------
TABLE 5. (continued)
CWith collection of CO from BOFs.
Assumes East Coast refinery model applied nationally.
22
-------
SECTION 3
PROCESS AND POTENTIAL PARTICULATE EMISSIONS
BASES OF CALCULATIONS
In Volume II (p. 19) where the methodology is described, we indicated
that selected State air emission regulations, along with the Federal
Government's stationary source performance standards and effluent limi-
tation guidelines, were surveyed to:
• establish the most probable limits of air emissions, and
• obtain a perspective of the types of pollution control
systems to be considered,
While there are a large number of different regulations for airborne
emissions, at the State regulatory level we found that approximately
the same type of air pollution control systems would be required, regard-
less of the State or Federal regulations to be met. Generally these air
pollution control systmes included baghouses, venturi scrubbers, inertial
collectors, and electrostatic precipitators for particulates and chemical-
based systems for sulfur removal, such as alkaline-based aqueous scrubbing
for SO .
x
In this section, we summarize specific methods of particulate control
of emissions from the process industries (Volumes III to XV), Only
point emissions, not area or fugitive emissions, are considered. There
are two sources of emissions: the processes themselves and power boilers.
While emissions from power boilers generally were not considered in the
original study, they are included in the present analysis to show the
net change in emissions resulting from a process change. For this dis-
cussion, power boilers are assumed to burn coal containing 12 percent
ash and having a heating value of 12,000 Btu/lb. Approximately 80 percent
of the ash appears as fly ash in the pulverized coal-fired boilers so the
estimated uncontrolled emission factor for boilers is 192 lb of particu-
late/ton of coal or 8 lb/10 Btu (0.084 Ib/kWh, based on 10,500 Btu/kWh).
This factor is identical to that reported in AP-42 (EPA, 1975). The New
Source Performance Standard (NSPS) established by the U.S. Environmental
Protection Agency (EPA) limits the emissions from new, pulverized coal-
fired,boilers with a capacity greater than 250 x 10 Btu/hr to 0.1
lb/10 Btu (equivalent to 0.00105 Ib/kWh). With existing economically
viable control technology (electrostatic precipitators, scrubbers, and
bagfilters), this level of control has been achieved. The particulate
*
Power boilers are used to generate steam and electricity. Both on-site
power boilers and off-site utility power boilers are considered and,
for the purposes of this study, both are presumed to be coal-fired.
23
-------
emission factors for the base case and alternative processes were esti-
mated, and then the effect of the estimated factors on the incremental
production from 1974 to 1989 was calculated.
Occasionally, a process involves obtaining a credit for by-product
energy such as steam. If the steam can be utilized, it will eliminate
the need for burning a fuel with its concommitant emissions. We show
such cases in this study as resulting in negative emissions.
PARTICULATE CONTROL METHODS
As indicated earlier, there are four types of equipment employed to
remove particulates: inertial collectors, bag filters, wet scrubbers,
and electrostatic precipitators.
Inertial Collectors
The cyclone is the most widely used inertial collector in industry.
Earticulates are separated from the gas stream by virtue of centrifugal
force acting on the particulates in the cyclones. Cyclones can effectively
separate particles over 5 microns in diameter (greater than 90% efficiency).
Bag Filters
Bag filters (or "baghouses", as they are often called) offer high
separation efficiency, even for small particle sizes. In most cases,
efficiencies range from 95% to more than 99%. Furthermore, bag filters
produce dry dust ready for use or disposal, and (unlike wet scrubbers)
they do not add a plume to the stack exhaust.
In the operation of a bag filter, dust-laden gas enters a porous
medium and deposits dust in the voids. As the voids fill up, the pres-
sure drop increases, and a point is reached when the fabric must be
cleaned. The operation is resumed after the cleaning process.
Wet Scrubbers
The major types of wet scrubbers available are: cross flow, counter-
current, wet cyclone, venturi, and vertical air washers.
Wet scrubbers have the following advantages:
• Ability to maintain constant pressure drop (a variable flow rate)
• No secondary dust problem, and
• Ability to handle high-temperature or high-humidity gases.
Scrubbers can handle corrosive gases or aerosols. Usually total space
requirements are moderate. But, in some cases, disposal of wastewater
is a severe secondary pollution problem.
24
-------
N3
100
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i_
on
— yu
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111
.1 80
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(3
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TO 0.001 y
Microns ~"~
Fabric-) — — | "
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60" A P
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ticX'"
20" A'
vw •
~- — '
X
s' .
(
S
••^^^
— — '
/
I
^ ^~
X
^K" A P
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crubbers
. .
^
=•—
-^
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^^*
igh Ef
- Cyc
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one
X
x
ncy
x,^"
t
*
Medium
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^•-*
/
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^
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x-"
5»^~
.2 0.3 0.4 0.6 0.8 1.0 2.0 3.0 4.0 6.0 8.0 10.0 20 30 40 60 80 10
Particle Diameter (microns)
/ Particle Size Range of Metallurgical Dusts and Fumes
Source: Arthur 0. Little, Inc.
FIGURE 1 PARTICULATE CONTROL DEVICE PERFORMANCE COMPARISON
-------
Electrostatic Precipitators
When suspended particulates in a gas are exposed to gas ions in an
electrostatic field, they become charged and migrate to the opposite
electrode. Electrostatic precipitators employ this method to separate
solid particulates or aerosols from gas streams. Precipitators are
made in two basic designs: plate type, mainly used to remove solids
from gas streams; and tube type, mainly used to remove aerosols and
fumes from gas streams.
Performance of Particulate Control Devices
The comparative performance of particulate control devices is shown
in Figure 1. The application range of the various types of equipment
is determined by the following factors:
• Particulate characteristics, such as particle size and size
distribution, particle shape, particle density, and physico-
chemical properties (corrosiveness, hygroscopic tendencies,
stickiness, flammability, toxicity, etc.);
• Carrier gas characteristics, such as temperature, pressure,
density, viscosity, dew points of condensable components,
electrical conductivity, corrosiveness, and flammability;
• Process factors, such as volumetric gas rate, particulate
concentration, variability of material flow rates, col-
lection efficiency requirements, and allowable pressure
drop; and
• Operational factors, including structural limitations
such as head room and floor space, and material limitations
such as pressure, temperature, and corrosion service
requirements.
IRON AND STEEL INDUSTRY
Summary
In the iron and steel industry, four alternative processes were studied;
• Recovery of carbon monoxide from the basic oxygen process (BOP),
• External desulfurization of blast-furnace hot metal,
• Conversion from wet to dry coke quenching, and
• Direct reduction of iron ore.
Each alternative corresponds to a different base case process.
Particulate emissions from the base case and alternative processes are
summarized in Tables 6 and 7. Further details on these four process
options are discussed next.
26
-------
TABLE 6. ESTIMATED PARTICULATE EMISSION FACTORS - IRON AND STEEL INDUSTRY
Process
Base case:
BOP with no off-gas
recovery
• Off-gas recovery
Emission factor - no control Emission factor - with control Control
(Ib/ton of product) (Ib/ton of product) efficiency
Process Power boiler Total Process Power boiler Total (%)
55.0 1.2 56.2 0.51 0.01 0.52 99.1
55.0 0.67 55.7 0,25 0.01 0.26 99.5
Base case:
Blast furnace 1.5 2.1 3.6 1.5 0.03 1.5 58.3
• Blast furnace with external
desulfurization 7.2 2.1 9,3 1.78 0.03 1.8 80.6
Base case:
Wet quenching of coke
• Dry quenching of coke
Base case:
Steelmaking
• Coke oven, BF, BOP route 58.0
• Direct reduction route
2.1
1.3
8.0
9.9
—
- 8.1
3.3
58.0
2.1
- 6.8
61.3
67.9
1.3
1.3 - 0.1
3.4 0.04
0.33 0.73
1.3
1.2
3.4
1.1
38.1
-
94.4
98.4
-------
TABLE 7. ESTIMATED PARTICULATE EMISSIONS - IRON AND STEEL INDUSTRY
Process
Total participate
controlled emission factor
Change in
Ib/ton of product emission factor
Particulate A
emissions for 1974-1989
AA(10b Ib/yr)
1974 1989-1974
00
Base case:
BOP with no off-gas recovery
• Off-gas recovery
Base case:
Blast furnace
• Blast furnace with external
desulfurization
Base case:
Wet quenching of coke
• Dry quenching of coke
Base case:
Steelmaking
• Coke oven, BF, BOP route
• Direct reduction, EAF route
0.52
0.26
1,5
1,8
1,3
1.2
3.4
1.1
- 0.26
+ 0.3
- .1
- 2.3
69.2
150.0
80.6
452.2
31.2
15.6
67.5
81.0
58.5
54.0
204.0
66.0
666
Based on production in 1989 being 45 x 10 tons of coke, 45 x 10 tons of iron, and 60 x 10 tons
of steel greater than in*1974.
(continued)
-------
TABLE 7. (continued)
** 6
Estimated,1974 emissions (based on the emission factor of 1.3 Ib/ton of coke) are 1.3 x 62 x 10
80.6 x 10 Ib from coke production; estimated 1974 emissions (based on the emission factor of
1.5 Ib/ton of iron) are 1.5 x 100 x 10 = 150 x 10 Ib from iron production; and estimated 1974
emissions (based on emission,factors of 0,52 Ib/ton of steel and,3.4 Ib/ton of steel) are
0.52 x 133 x 10 = 69.2 x 10 Ib or 3.4 x 133 x 105 = 452.2 x 10 Ib from EOF furnaces and from
steelmaking process, respectively.
-------
Basic Oxygen Process (BOP) for Steelmaking
Base Case Process - BOP Off-Gas/No Recovery—
BOP off-gas consist largely of carbon monoxide and thus are highly
combustible. In conventional practice, no provision is made to prevent
air from contacting the flue gas, and thus the hot gases combust spon-
taneously in the gas-collecting hood.
About 55 Ib of particulate/ton of steel are produced in the BOP
(Volume III, page 23). The dust particules are oxidized due to combus-
tion. Approximately 25% of the particles are below 1 micron in size.
Either electrostatic precipitator or a wet scrubber can be used to
control such emissions. The pressure drop in the scrubber is 40 to 65
inches of water and the cleaned gas contains less than 0.05 gr/scf
(grains/standard cubic foot), equivalent to about 0.51 Ib/ton of steel
(EPA, 1975). Efficiencies of electrostatic precipitators and scrubbers
are comparable.
Electricity consumption in the base case process is about 14 kWh/ton
of steel (Volume III, page 28). Estimated emissions from a power boiler
are 1.20 Ib/ton of steel with no control, and 0.01 Ib/ton of steel with
control to meet the NSPS.
Process Option - BOP Off-Gas Recovery—
In this alternative, air infiltration in the hood, which caused com-
bustion of the hot gas in the base case process, is prevented by a closely
spaced hood. The gas—after cooling and cleaning—is available as
gaseous fuel for general-purpose use. (A detailed description of the
process is given in Volume III, page 19.)
In this non-combustion alternative, the dust is composed mainly of
FeO, magnetite and small amounts of metallic iron. Because FeO and
magnetite agglomerate more easily than hematitie (present in the base
case process as the result of spontaneous combustion), the dust particles
in this alternative are larger than those emitted from the base case
process. A particle-size distribution with 9% of the particles smaller
than 5 microns for the off-gas system has been reported (Volume III,
page 24). It is not possible to recover 100% of the gas because of the
operating conditions (cyclic operation and the presence of combustible
gas). Nevertheless, the estimated particulate control efficiency for
the system is 99.5%, so that controlled emissions are estimated to be
about 0.25 Ib/ton of steel. The size of the control equipment in this
alternative is smaller than that in the base case process because the
prevention of air infiltration results in a smaller flue gas volume.
30
-------
Presence of carbon monoxide in the flue gas creates fire and
explosion hazards not present in the base case process. This makes
the electrostatic precipitator system unsuitable for the collection of
the carbon monoxide off-gas in the alternative process.
The electricity consumption in this alternative process is about
8 kWh/ton of steel (Volume III, page 27). Estimated emissions from a
power boiler are 0.67 Ib/ton of steel with no control, but would remain
0.01 Ib/ton of steel with control to meet the NSPS.
Blast Furnace (BF)
Base Case Process—
The base case process includes a blast furnace and a gas-cleaning
system. The gas-cleaning device (cyclone and venturi scrubber) is con-
sidered part of the process equipment, because it generates a low-Btu
fuel gas. The exhaust gas from the scrubber contains particulates con-
sisting of 35 to 50 percent iron, 4 to 14 percent carbon, 8 to 13 percent
silicon dioxide, and small amounts of aluminum oxide, manganese oxide,
calcium oxide, and other materials. Controlled emissions are reported
to be 1.5 Ib/ton of steel (EPA 1975). because the clean gas is valuable,
the control equipment is considered to be a part of the system.
Electricity consumed in the base case process is 25 kWh/ton of hot
metal (Volume III, page 44). Estimated emissions from a power boiler
are 2.1 Ib/ton of hot metal with no control, and 0.03 Ib/ton of hot
metal with control to meet the NSPS.
Process Option - Blast Furnace with External Desulfurization—
In the base case process, blast furnace sulfur content is completely
controlled by adding limestone to form a sulfur-bearing slag and by
limiting the sulfur content of the metallurgical coke. Addition of an
external desulfurization step is an alternative method of controlling
the sulfur content of blast furnace hot metal. External desulfurization
is achieved by injecting sulfur-reacting reagents (e.g., calcium or
magnesium compounds carried in an inert gas such as nitrogen) into a
high-sulfur, hot-metal produced in a blast furnace. These compounds
form a sulfide slag that is skimmed off prior to charging the hot metal
to the BOP. Use of external desulfurization either permits limestone
and coke ratios to be reduced, or allows the sulfur content in the
coke to be increased without increasing the limestone charge to the furnace,
which has other disadvantages. (A detailed description of this process
is given in Volume III, page 29.)
Addition of the external desulfruization step results in an additional
emission source. Based on the gas flow rate of 26,500 acfm for 50% of
the time (Volume,III, page 35) from a facility with annual production
rate of 2.6 x 10 ton/yr, the gas flow rate is at 3,000 actual cubic
ft/ton of hot metal from the external desulfurizer at an estimated 650).
31
-------
The particulate loading in the gas is 0.0025 Ib/scf (Volume III, page 35),
which is equal to 5.7 Ib/ton of hot metal. The particulates consist of
iron oxide, unreacted desulfurizer, and produce slag and result mostly
from entrainment rather than condensation of vaporized metal compounds.
Therefore, the particulates are larger than those from the BOP or the
blast furnace without external desulfurization. A venturi scrubber with
medium pressure drop can be used for this control application. Esti-
mated collection efficiency is 95 percent, so the controlled emissions
are about 0.25 Ib/ton of hot metal.
Therefore, the uncontrolled emissions from this alternative, including
the blast furnace, are 7.2 Ib/ton of hot metal, and the controlled
emissions are 1.78 Ib/ton of hot metal.
Electricity consumption in this alternative is the same as that in
the base case process, so power boiler emissions are identical.
Wet Quenching of Coke
Base Case Process—
The base case process includes pushing of coke from the coke oven
and wet quenching. A detailed description of the process is given in
Volume III, page 48. When the coke is pushed from the coke oven, con-
vection currents carry off the dust from the coke. If there is uncoked
material, combustion of its volatile constituents will create additional
smoke and set up stronger gas flows, which cause additional emissions.
Uncontrolled coke pushing emissions have been reported to be 0.6 Ib/ton
of coal (EPA 1975).
Control methods include wet scrubbing. The controlled emissions
cannot be estimated, because no data are available.
Quench towers represent the other source of particulate emissions.
Recent data indicate emission rates of about 1.5 Ib/ton of coal for
operations using fresh water with no dissolved solids (TDS = 0), increasing
linearly to 5 Ib/ton of coal for operations using water with TDS = 20
Ib/ton of water (Ref. 1). Installation of baffles in the quench tower
is claimed to remove solid particulates with about 50 percent collection
efficiency.
The total uncontrolled emissions are 2.1 Ib/ton of metal, based on
use of fresh water in the quench tower. The controlled emissions are
estimated at less than 1.31 Ib/ton of metal. The electricity consumption
in this process is very low so power boiler emissions are negligible.
Process Option - Dry Quenching of Coke—
In dry quenching of coke, the coke is cooled by an inert gas stream.
The sensible heat transferred to the inert gas can then be partially
32
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recovered for reuse. (A detailed description of the process is given in
Volume III, page 48.)
Coke dust could still be discharged to the atmosphere during the coke-
pushing operation. The emission loads are expected to be approximately
the same as those in the base case process. In addition, several sources
in the dry quenching operation emit fugitive or minor particulate
emissions. However, such emissions cannot be quantified, because data
are not available. The dry quench system is basically a closed system
and control of particulates must be considered inherent in the process.
PETROLEUM REFINING INDUSTRY
Base Case Process - 1985 Refinery
A description of the petroleum refining industry is presented in
Volume IV, page 9. In assessing the impact of process changes in the
refining industry, a 1985 refinery configuration was used as a base
case. The reasons for using this approach are given in Volume IV, page
22. Three configurations were selected to represent the local conditions:
East Coast, Gulf Coast, and West Coast.
East Coast Refinery
Base Case Process—
The base case East Coast refinery is described in Volume IV, page 23.
The energy intake in this refinery is 1.31 x 10 Btu/day and production
is equivalent to 1.19 x 10 Btu/day (Volume IV, page 35). The energy
intake and production are assumed for the year 1985.
The major airborne pollutants emitted by refineries are identified
in Volume IV, page 22. The emission factors summarized in EPA 1975
were used to determine particulate emissions from the base case refinery.
The particulate emissions estimated in Volume IV, page 24, are about
880 Ib/day from gas-fired process heaters and boilers (uncontrolled),
8,100 Ib/day from oil-fired heaters and boilers (uncontrolled), and
2,800 Ib/day from fluid catalytic crackers (controlled). The total
emissions (11,780 Ib/day) are equivalent to about 9.9 lb/10 Btu of
refinery output. The above emissions from the heaters and boilers are
not controlled, while those from the fluid catalytic crackers are con-
trolled in electrostatic precipitators.
The uncontrolled emissions from the fluid catalytic crackers are
estimated to be 15,100 Ib/day. The total uncontrolled particulate
emissions (24,080 Ib/day) from the refinery are equivalent to about
20 lb/10 Btu of refinery output.
33
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Based on the electricity consumption of 8.9 x 10 Btu/day and the
steam consumption of 8.1 x 10 Btu/day (Volume IV, page 35), estimated
emissions from the power boiler are 115 lb/10 Btu of refinery output
with no control, and 1.4 lb/10 Btu of refinery output with control
to meet the NSPS.
Process Option 1 - Direct Combustion of Asphalt in Process Heaters and Boilers—
A detailed description for this alternative appears in Volume IV,
page 32. Utilizing asphalt for combustion is done primarily to upgrade
the overall form value of refinery products, rather than to actually
increase overall thermal efficiency within the refinery. Part of the
refinery gas (36.6%) and all of the fuel oil are displaced by asphalt.
The energy balances for the base case process and the alternative are
summarized in Volume IV, page 35.
In the alternative process, particulate emissions are increased because
of higher emissions from asphalt combustion compared to those from gas
or oil combustion. The particulate emissions from asphalt combustion
are about 12,000 Ib/day (Volume IV, page 38). The emissions from the
gas-fired heaters and boilers are decreased from 8,100 Ib/day (in the
base case process) to 600 Ib/day because of the reduced consumption of
gas. The net increase in emissions in this alternative from the base
case process is 4,500 Ib/day. The total uncontrolled particulate emissions
are about 28,580 Ib/day (24.0 lb/10 Btu of refinery output) and the
controlled emissions are about 16,300 Ib/day (13.7 lb/10 Btu of refinery
output).
Based on the electricity consumption of 8.9 x 10 Btu/day and the
steam consumption of 9.7 x 10 Btu/day (Volume IV, page 35), estimated
emissions from power boilers are 125 lb/10 Btu of refinery output with
no control, and 1.6 lb/10 Btu of refinery output with control to meet
the NSPS.
Process Option 2 - Flexicoking Process Alternative—
Flexicoking is the combination of fluid coking with coke gasification.
Although fluid coking is a commercially available technology, there are
no commercially operating flexicokers. (A detailed description of the
process is given in Volume IV, page 52.)
An additional particulate emission source in the alternative is the
fluid coker. However, data on uncontrolled emissions from this source
are not available. Exxon claims complete removal of particulates in a
control device (Volume IV, page 57). Therefore, controlled emissions
are taken to be the same as in the base case process, or about 9.9 lb/10
Btu of refinery output.
g
Based on the electricity consumption of 9.6 x 10 Btu/day and the
steam consumption of 7.6 x 10 Btu/day (Volume IV, page 58), estimated
34
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emissions from power boilers are 120 lb/10 Btu of refinery output with
no control, and 1.5 lb/10 Btu of refinery output with control to meet
the NSPS.
Gulf Coast Refinery
Base Case Process—
The base case Gulf Coast refinery feedstock configuration for the
year 1985 is described in Volume IV^ page 23. Total energy input in
the base case refinery is 1.31 x 10 Btu/day and production is equiva-
lent to 1.2 x 10 Btu/day. The particulate emissions in the Gulf
Coast base case refinery are evaluated in a manner similar to that used
for the East Coast base case refinery.
o
Based on the electricity consumption of 9.2 x 10 Btu/day and the
steam consumption of 0.7 x 10 Btu/day (Volume IV, page 70), estimated
emissions from the power boiler are 66 lb/10 Btu of refinery output
with no control, and 0.83 lb/10 Btu of refinery output with control to
meet the NSPS.
Based on the uncontrolled emission factor of 242 lb of particulate/10
lb of fresh fuel (Volume IV, page 147) and the fuel rate, and the uncon-
trolled emissions from the heaters and boilers, 9,850 Ib/day (Volume IV,
page 25), the total uncontrolled emissions are estimated at 29,300 Ib/day,
equivalent to 24 lb/10 Btu of refinery output. Emissions from the heaters
and boilers are not controlled and therefore the controlled emissions are
estimated at about 13,400 Ib/day (Volume IV, page 25), equivalent to
about 11 lb/10 Btu of refinery output.
Process Opiton - On-site Electric Power Generation by Combustion of Asphalt—
In this process alternative, electric power is generated within the
refinery rather than purchased from a local electric utility. The fuel
is assumed to be asphalt. A simplified flow sheet for this alternative
is shown in Volume IV, page 69.
Generation of electric power within the refinery neither conserves
energy nor consumes more energy than when power is purchased, assuming
that the on-site and off-site power plants would operate at the same
efficiencies. In effect, the form value of the asphalt is upgarded to
a higher form value of electric power for refinery use. The design
capacity of the generator is 36.5 megawatts (Volume IV, page 77).
Because of on-site power generation, this process alternative will
result in increased on-site emissions. Particulate emissions from the
power boiler are 1,226 Ib/day (Volume IV, page 73), equivalent to about
1.0 lb/10 Btu of refinery output. These emissions will have to be
controlled to meet the NSPS to about 0.76 lb/10 Btu of refinery outputQ
Particulate emissions from the process are not affected (about 24 lb/10
Btu of refinery output with no control, and about 11 lb/10 Btu of refinery
output with control).
35
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Because of the reduced consumption of electricity from an off-site
power boiler, estimated emissions from off-site power boilers (coal-fired)
are reduced toQabout 4.7 lb/10 Btu of refinery output with no control,
and 0.05 lb/10 Btu of refinery output with control to meet the NSPS.
The total estimated particulate emissions from on-site and off-site
power boilers are about 5.7 lb/10 Btu of refinery output with no control
and 0.81 lb/10 Btu of refinery output with control to meet the NSPS.
West Coast Refinery
Base Case Process—
The West Coast base case refinery feedstock configuration for the
year 1985 is described in Volume IV. page 23. Total energy input in
the base case refinery is 1.0 x 10 Btu/day and production is equivalent
to 0.95 x 10 Btu/day.
Particulate emissions in this base case process are evaluated in a
manner similar to that used for both the East Coast and Gulf Coast base
case refineries. Uncontrolled emissions from the refinery are estimated
at about 20,000 Ib/day, equivalent to about 21 lb/10 Btu of refinery
output. Controlled emissions are estimated at about 12,500 Ib/day
(Volume IV, page 26), equivalent to about 13 lb/10 Btu of refinery
output.
Q
Estimated emissions from power boilers are about 80 lb/10 Btu of
refinery output with no control, and about 1.0 lb/10 Btu of refinery
output with control to meet the NSPS.
Process Option - Hydrocracking of Heavy Bottoms—
In this option, asphalt is used as a feedstock for a hydrocracking
process (such as H-oil or Isomax) in which the heavy bottoms are con-
verted to lighter fuel oil and gaseous products. The H-oil process was
chosen to exemplify a heavy-ends hydrocracking process. (A detailed
description of the process is given in Volume IV, page 43.)
Because asphalt is used for combustion to replace hydrogen (used in
the base case process), the addition to base case particulate emissions
from process is 674 Ib/day (Volume IV, page 48). Thus, total uncontrolled
particulate emissions are about 20,675 Ib/day, equivalent to about
22 lb/10 Btu of refinery output. The controlled emissions are estimated
at about 13,175 Ib/day, equivalent to about 14 lb/10 Btu of refinery
output. Particulate emissions from power boilers in this alternative
are the same as those for the base case process.
Process Option - High-Purity Hydrogen Production via Partial Oxidation
of Asphalt—
This alternative is based on the production of high-purity hydrogen
for hydrotreating from vacuum bottoms, using a partial oxidation process.
The feedstock freed up by this approach would then be available for sale
36
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outside the refinery in the form of pipeline gas or naphtha. A detailed
process description is given in Volume IV, page 78. Particulate emissions
from the process and power boilers in this alternative are the same as
for the base case process.
Summary
The uncontrolled and controlled emission factors for petroleum
refining are shown in Table 8. As given in the table, the particulate
emissions in the alternative process are comparable to those in the
corresponding base case processes, except for the direct combustion of
asphalt in process heaters and boilers. The emissions in this alternative
are 35% higher than those in the base case process. The particulate
emissions from the processes studied are shown in Table 9.
However, with implementation of available control technology, the
difference becomes slight enough that problems with praticulates should
not have a significnat impact on the industry's selection of alternative
processes in the future. It is also not expected that the character
of the particulate emissions will be sufficiently different to imporve
or complicate removal. The one exception may be the use of direct
combustion of asphalt which would result in a 5% increase (hypothetically)
in emissions from 424 x 10 Ib in 1974 with the base case to 453 x 10
Ib in 1989 if the option is implemented only for the incremental production.
It may also be of interest to point out that the uncontrolled emissions
from the power plant are typically much larger than process emissions.
Yet, efficiency of control is much higher for the power plant so that
the processes account for the major portion of the controlled emissions.
PULP AND PAPER INDUSTRY
Chemical Pulp
Base Case Process - Kraft Pulping—
The base case process selected for chemical pulp was the Kraft
process, which includes cooking of wood chips at an elevated temperature
and pressure in a digester. When cooking is completed, the contents of
the digester are forced into a blow tank. The major portion of the
spent cooking liquor, which contains the dissolved lignin, is drained,
and the pulp then enters the initial stage of washing. From the blow
tank the pulp passes through the knotter where chunks of wood are removed.
The pulp is then washed and bleached before being pressed and dried into
the finished product.
It is economical to recover both the inorganic cooking chemicals
and the heat content of the spent liquor which is separated from the
cooked pulp in the blow tank. Recovery is accomplished by first con-
centrating the liquor to a level that will support combustion, and then
feeding it to a furnace (recovery boiler) where heat and chemical recovery
take place.
37
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TABLE 8. ESTIMATED PARTICULATE EMISSION FACTORS - PETROLEUM REFINING INDUSTRY
oo
a
Emission factor - no control
•3
Emission factor - with control
Control
(lb/10 Btu of refinery output) (lb/10* Btu of refinery output) ef ficienc;
Process Process Power boiler Total Process Power boiler Total (%)
Base case:
East Coast refinery
• Direct combustion of
asphalt in process
heaters and boilers
• Flexicoking
Base case:
Gulf Coast refinery
• On-site electric power
by combustion of asphalt
Base case:
West Coast refinery
• Hydrocracking of
heavy bottoms
• High-purity hydrogen
production via partial
oxidation of asphalt
20.0
24.0
N,A.
24.0
24.0
21.0
22.0
21.0
115.0
125.0
120,0
66.0
5.7
80.0
80.0
80.0
135.0
149,0
N.A.
90.0
29.7
101,0
102.0
101.0
9.9
13.7
9.9
11.0
11,0
13.0
14,0
13.0
1.4
1.6
1.5
.83
.81
1.0
1.0
1.0
11.3
15.3
11.4
11.8
11.8
14.0
15.0
14.0
91.6
89.7
N.A.
86.9
60.3
86.1
85.3
86.1
Emissions reported as Ib particulate/10 Btu of refinery output.
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TABLE 9. ESTIMATED PARTICULATE EMISSIONS - PETROLEUM REFINING INDUSTRY
(Ib
Process of
Base case:
East Coast refinery
• Direct combustion of asphalt
in process heaters and boilers
• Flexicoking
Base case: ,
Gulf Coast refinery
• On-site electric power by
combustion of vacuum bottoms
Base case:
West Coast refinery
• Hydrocracking of heavy bottoms
• High purity hydrogen production
via partial oxidation of asphalt
Emission factor
particulate/10 Btu
refinery output)
11.3
15.3
11.4
11,8
11.8
14.0
15.0
14.0
Particulate emissions
Change in (10 Ib/yr)
emission factor 1974 1989-1974a
339. Ob 84. 8a
+ 4.0 — 114.8
+ .1 — 85.5
354. Ob 88.5
0 — 88.5
420. Ob 105.0
+ 1.0 — 112.5
0 — 105.0
Based on incremental national production from 1974 to 1989 equal to 7.5 quads (7.5 x 10 Btu)
multiplied by emission factor assuming no retirement of existing facilities.
Estimated 1974 emissions, based on the total emission factors and production of 30 quads are
339 x 10 Ib, 354 x 10 Ib and 420 x 10 Ib for East Coast, Gulf Coast and West Coast models,
respectively.
-------
Uncontrolled particulate emissions from the Kraft pulp process include
130 Ib/ton of pulp from the recovery boiler, 5 Ib/ton of pulp from the
smelt tank, 18 Ib/ton of pulp from the on-site power boiler, and 45 Ib/ton
of pulp from the lime kiln (Volume V, page 172). Total uncontrolled
process emissions are therefore 180 Ib/ton of pulp, and on-site power
boiler emissions are 18 Ib/ton of pulp.
The U.S. Envionmental Protection Agency's standards for new Kraft
pulp mills are presently at the proposal stage. The proposed standards
limit particulate emissions to 2.0 Ib/ton of pulp from the recovery
boiler, 0.55 or 1.07 Ib/ton of pulp from the gas- or oil-fired lime
kilns, respectively, and .0.15 Ib/ton of pulp from the smelt tank.
Therefore, total controlled process emissions should be less than
3.2 Ib/ton of pulp.
Present control methods used are scrubbers or electrostatic pre-
cipitators for recovery boilers and lime kilns, and packed-bed or low-
energy scrubbers for smelt tanks. It is these technologies which are
used to reach the proposed standards.
Combination boilers or bark boilers are used as on-site power boilers
in the pulp industry. The air pollution control system for these boilers
consists of a mechanical collector followed by an electrostatic pre-
cipitator or a scrubber. On-site power boiler capacity is about
5 x 10 Btu/ton of pulp (Volume V, page 57). Controlled boiler emissions
are estimated at 0.5 Ib/ton of pulp (uncontrolled emissions are 18 Ib/ton
of pulp). About 140 kWh/ton of pulp electricity is credited in the
process (Volume V, page 57). The particulate emissions from utility
power boilers which are offset by this credit are estimated at about
12 Ib/ton of pulp with no control, and 0.15 Ib/ton of pulp with control
to meet the NSPS. Therefore, total emissions from both on-site and off-
site power boilers are estimated at 6 Ib/ton of pulp with no control,
and 0.35 Ib/ton of pulp with control to meet the NSPS.
Process Option 1 - Alkaline-Oxygen Pulping—
The alkaline-oxygen (A-0) pulping process is receiving attention in
the industry, because of its potential for a non-sulfur cooking step
which would eliminate the air pollution due to sulfur compounds. The
steps in the A-0 process include an alkaline treatment to soften the
wood chips, mechanical disintegration, and treatment with oxygen under
alkaline conditions to remove most of the lignin, followed by the last
three stages of the conventional multistage bleaching sequence: chlorine
dioxide, caustic extraction, and chlorine dioxide. (A detailed description
of the process is given in Volume V, page 84.)
The uncontrolled emissions from the alternative process include
110 Ib/ton of pulp from the recovery boiler, 2 Ib/ton of pulp from the
smelt tank, and 19 Ib/ton of pulp from the lime kiln (Volume V, page 172).
Therefore, total particulate emissions are 131 Ib/ton of pulp. The
particulate control methods used for this alternative are the same as
40
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those for the base case process. Controlled emissions are estimated at
less than 3.2 Ib/ton of pulp, or the same as those in the base case
process.
Uncontrolled emissions from on-site power boilers are 15 Ib/ton of
pulp (Volume V, page 172). Controlled emissions are estimated at about
0.42 Ib/ton of pulp. About 50 kWh/ton of pulp electricity are credited
in the process (Volume V, page 86). The particulate emissions from
utility power boilers which are offset by this credit are estimated at
about 4 Ib/ton of pulp with no control, and 0.05 Ib/ton of pulp with
control to meet the NSPS. Therefore, total emissions from both the on-
site and off-site power, boilers are estimated at 11 Ib/ton of pulp
with no control, and 0.37 Ib/ton of pulp with control to meet the NSPS.
Process Option 2 - Rapson Effluent-free Kraft Pulping—
A number of changes in the base case pulping process have been made
to eliminate effluents in the modified process, called the Rapson
effluent-free Kraft process. (It is described in detail in Volume V,
page 95.) The particulate emission control methods and controlled
emissions for the Rapson process are the same as those for the base case
process.
Uncontrolled emissions from on-site power boilers are estimated at
about 18 Ib/ton of pulp. Controlled emissions are estimated at 0.2 Ib/ton
of pulp. On-site power boiler capacity is sufficient to meet the steam
and electricity requirements of this alternative process.
Newsprint Pulp
Base Case Process - Refiner Mechanical Pulping (RMP) Route for Newsprint Pulp—
RMP is a mechanical pulping process that itself is an improvement
over the conventional groundwood process. Wood chips, sawdust, and shavings
from swamills or plywood mills can be used as raw materials for the RMP
process, but such materials cannot be used as raw materials for the ground-
wood process. The wood particules are reduced in a pressurized disc
refiner which consists of two circular metal plates that generally rotate
in opposite direction. RMP pulp (80%) is used with Kraft pulp (20%) in
newsprint paper production with both processes contributing directly or
indirectly to process emissions. (A detailed description of the RMP
process is given in Volume V, page 60.)
Kraft pulp, contributing 20% of the newsprint pulp in the base case
process, involves particulate emissions from the process that were deter-
mined to be 180 Ib/ton of Kraft pulp with no control and about 3.2 Ib/ton
of Kraft pulp with controls to meet the proposed NSPS. The total parti-
culate emissions from the power boiler in the Kraft process were estimated
at 6.0 Ib/ton of Kraft pulp with no control and at 0.35 Ib/ton of Kraft
pulp with control to meet the NSPS.
41
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There are no major emission sources in the RMP process, except possibly
for power boilers, since hydroelectric power is often used. Based on the
electricity consumption of 1,475 kWh/ton of RMP pulp and the use of coal-
fired power boilers, emissions are estimated at 124 Ib of particulate/
ton of RMP pulp with no control, and 1.6 Ib of particulate/ton of RMP
pulp with control to meet the NSPS. Thus with 80% RMP pulp in newsprint
production, the RMP process power boilers contributes 1.28 (=0.2 x 0.35)
Ib of particulate emissions giving total boiler emissions of 1.35 Ib
particulates/ton RMP based newsprint pulp. Based on the above, the total
process emissions are estimated to be all derived from the 20% pulp
contribution by the Kraft process which account for 36 Ib particulate/ton
of newsprint pulp with no control and 0.64 Ib/ton of newsprint pulp with
control to meet NSPS. The power boiler emissions derived from the RMP
process and Kraft process are calculated at about 99.3 Ib/ton of newsprint
paper with no control and at about 1.35 Ib/ton of newsprint paper with
control to meet NSPS. Thus, total controlled emissions are estimated to
be 1.99 (+ 0.64 + 1.35) Ib particulate/ton of newsprint which has been
rounded to 2.0 Ib particulate/ton of newsprint in Table 10.
Process Option 1 - Thermo-Mechanical Pulping (TMP)—
The TMP process is similar to the base case process (RMP process)
except the wood particles are preheated to 130°C for a short period and
then reduced to fibers in a pressurized di.cc refiner.
For production of newsprint, 0.95 ton of TMP pulp and 0.05 ton of
Kraft pulp are used per ton of newsprint pulp. Again particulate emissions
from the process are derived from the contribution from Kraft pulping.
With 5% Kraft pulp, process particulate emissions are estimated from
the information derived above to be 0.05 x 180 = 9 with no control and
0.05 x 3.2 = .16 Ib/ton of newsprint with control.
As in the base case RMP process, there are not major emission sources
in the TMP process, except for power boilers. With electric energy
generated by a power boiler, emissions are the same as those in the base
case RMP process, namely 124 Ib/ton of TMP pulp with no control and 1.6
Ib/ton of RMP pulp with control. Controlled emissions from the power
boilers are calculated to be 0.95 x 1.6 = 1.52 Ib particulate/ton of
newsprint pulp from the TMP process and 0.05 x 0.35 = 0.0175 Ib particulate/
ton from the Kraft process. This sums to about 1.54 Ib particulate/ton
of newsprint pulp. Total controlled emissions are thus estimated to be
.06 + 1.54 = 1.70 Ib particulate/ton of newsprint pulp.
Process Option 2 - De-inking of Old Newsprint for Newsprint Manufacture
The de-inking of old newsprint for newsprint manufacture is a well-
established commercial practice. A detailed description of the process
is given in Volume V, page 113.
42
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TABLE 10. ESTIMATED PARTICULATE EMISSION FACTORS - PULP AND PAPER INDUSTRY
Process
Base case:
Kraft pulp
• Alkaline-oxygen
pulping
• Rapson effluent-
free Kraft
Emission factor - no control Emission factor - with control Control
(Ib/ton of pulp*) (Ib/ton of pulp) efficiency
Process Power boiler Total Process Power boiler Total (%)
180.0 6.0 186.0 3.2 0.35 3.6 98.1
131.0 11.0 142.0 3.2 0.37 3.6 97.5
180.0 18,0 198.0 3.2 0.2 3.4 98.3
Base case:
Refiner-mechanical
pulping (80% and
Kraft 20%)
• Thermo-mechanical
pulping (95% and
Kraft 5%)
• De-inking of old news-
print for newsprint
manufacture
36.0
9.0
99.3
118.1
49.0
135.3
127.1
49.0
0.64
0.16
1.35
1.54
0.61
2.0
1.71
0.61
98.5
98.9
98.8
Air-dry basis.
-------
There are no major emission sources in this alternative,except for
power boilers. Based on the energy consumption of 6.1 x 10 Btu/ton of
newsprint pulp (Volume V, page 115), particulate emissions from the
power boilers are estimated at 49 Ib/ton of pulp with no control, and
0.61 Ib/ton of pulp with control to meet the NSPS. In this case, it
is presumed that all energy is purchased and no energy value is credited
from waste.
Summary
Estimated particulate emission factors for the pulp and paper indus-
try are shown in Table 10. The uncontrolled emissions in the A-0 pulping
alternative process are about 25% lower than for the base case process.
The uncontrolled emissions in the Rapson process are comparable to those
in the Kraft base case process. The uncontrolled emissions in the alter-
native processes for newsprint production are about 30% lower than the
base case process.
The final or controlled particulate emission problems in all the
processes (except de-inking of old newsprint for newsprint manufacture)
are similar, and control methods used in these processes are the same.
(Emissions in the manufacture of newsprint are present from the Kraft
process only.) The controlled emissions in the alternative processes
for the manufacture of newsprint are about 30 to 50% lower than those
in the base case process. The estimated particulate emissions in the
pulp and paper industry are shown in Table 11.
Thus, while uncontrolled emissions are lower in the A-0 process,
once conventional technology is implemented for control, the benefit
decreases. Whether the reduced requirement to achieve that level is
significant is, however, doubtful and it is unlikely that particulate
levels or control would be a factor in selecting a process. Elimination
of the sulfur (TRS) energy saving would be much more important, the
latter more true for the Rapson process.
The same statements are related to Kraft vs A-0 or Rapson pulp use
in either RMP- or TMP-based newsprint. However, de-inking of existing
newsprint offers even less particulate emissions and conserves more
energy.
OLEFIN INDUSTRY
Ethylene Production
Base Case Process - Ethylene Production Based on Ethane and Propane Crackine-
The base case technology selected for the assessment of the domestic
olefin industry was ethane and propane (E-P) cracking. (A detailed
description of the process of producing ethylene from ethane and propane
is given in Volume VI. page 16.)
44
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TABLE 11. ESTIMATED PARTICIPATE EMISSIONS - PULP AND PAPER INDUSTRY
Total controlled
particulate emission factor
Process
Base case:
Kraft pulp
• Alkaline-oxygen pulping
• Rapson effluent-free Kraft
Base case:
Refiner mechanical pulping
• Thermo-mechanical pulping
• De-inking of old newsprint for
newsprint manufacture
(Ib/ton of pulp)
3.6
3,6
3,4
2.0
1,4
0.61
Change in
emission factor
-
0
-0.2
-
-0.6
-1.39
Particulate
emissions
(106 Ib/yr)
1974
57.6
7.8
1989-1974*
62.3
62.3
59.0
3.4
2.4
1.0
* 66
Based on emissions in 1989 being 17.3 x 10 tons of pulp and 1,7 x 10 ton of newsprint greater
than in 1974.
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The major source of particulate emissions in an ethylene plant is
the intermittent decoking of process furnaces. High-temperature steam
is used to react with or otherwise loosen and remove coke from the
furnace coils. A typical decoking cycle lasts for 16 hours. Since
decoking of furnaces is required after 40 days, even the largest plants
should be easily served by a single operating decoking scrubber system.
In such a control system, a spray tower is used to scrub out the parti-
culates.
A second source of particulate emissions is the regeneration of the
acetylene converter. This operation is similar to furnace decoking
in that steam or air is used to burn out residual oil and carbon
deposits from the converter. The regeneration is carried out once or
twice a year and takes about 48 hours. The same scrubber control system
used for the decoking operation can be used to control emissions from
the regeneration of the acetylene converter.
Uncontrolled intermittent emissions from the decoking operation are
41.6 Ib/hr from an ethylene plant having a capacity of 1.1 x 10 Ib/yr
(Volume VI, page 34). Data on the uncontrolled intermittent emissions
from the regeneration of the converter are not available, but may be
comparable to those from the decoking operation. The emissions are
generated for an average of 955 hr/yr from the above two sources
(Volume VI, page 51). Therefore, uncontrolled emissions are estimated
at 0.072 Ib/ton of ethylene.
Controlled intermittent emissions from the decoking operation are
0.9 Ib/hr. Data on the controlled emissions from the regeneration of
the converter are not available, but may be comparable to those from
the decoking operation. The estimated controlled emissions are 0.002 Ib/ton
of ethylene.
Fuel is consumed in the process heaters at a rate equivalent to
7,800 Btu/lb of ethylene (Volume VI, page 28). Estimated uncontrolled,
emissions from this source — based on the emission factor of 10 lb/10
cu ft of gas (AP-42) — are 0.15 Ib/ton of ethylene. Because of the
low emission rate, these emissions are not controlled. Consequently,
total uncontrolled emissions from the process are 0.22 Ib/ton of ethylene
and controlled emissions are estimated at 0.15 Ib/ton of ethylene with
the decoking and converting operations contributing a negligible quantity.
The electricity consumption in the base case process is equivalent
to 900 Btu/lb of ethylene, and the steam consumption is equivalent to
8,000 Btu/lb of ethylene. It is assumed that steam is generated in an
on-site natural gas boiler and that electricity is purchased. The
estimated emissions from the on-site power boiler are 0.15 Ib/ton of
ethylene. The estimated emissions from off-site power boilers (presumed
to be coal-fired) are 14.4 Ib/ton of ethylene with no control, and
0.18 Ib/ton of ethylene with control to meet the NSPS. The total
emissions from the boilers are estimated at about 14.6 Ib/ton of ethylene
with no control, and about 0.33 Ib/ton of ethylene with control to meet
the NSPS.
46
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Process Option 1 - Ethylene from the Pyrolysis of Naphtha—
Pyrolysis of naphtha already accounts for 7% of domestic ethylene
production and is the predominant technology used in Europe and Japan.
(This process alternative is described in Volume VI, page 22.)
As with the base case, the major sources of particulates during the
manufacture of ethylene from heavy feedstocks are the intermittent
decoking of process furnaces and regeneration of the converters. The
amount of coke built up within a process furnace at the time decoking
is required is the same for heavy feedstocks as it is for the base case.
However, the rate of buildup in the furnace is higher because the heavier
feedstocks produce more coke. Also, the quantity of feedstocks processed
is increased in this alternative. Hence, the amount of steam required
per decoking operation is the same as for the base case; the control
equipment required will be the same as that for the system described
in the base case process.
The uncontrolled emission rate to the scrubber (during operation)
is the same as in the base case process; viz., 41.6 Ib of particulate/hr.
The scrubber is operated an average of 1,788 hr/yr (Volume VI, page 51).
Estimated uncontrolled emissions are 0.13 Ib/ton of ethylene. The
controlled emissions from the scrubber are higher, about 1.3 Ib/hr, for
this alternative than for the base case process. The estimated emissions
from the scrubber are equivalent to 0.004 Ib/ton of ethylene.
Fuel is consumed in the process heaters at a rate equivalent to
10,300 Btu/lb of ethylene. Estimated emissions from this source - based
on the emission factors of 10 lb/10 cu ft of gas (AP-42) - are 0.20 Ib/ton
of ethylene. There is no control requirement at this time for this
source.
Total uncontrolled emissions from the process are 0.33 Ib/ton of
ethylene with no control, and controlled emissions are estimated at
0.20 Ib/ton of ethylene.
The electricity consumption in the alternative process is equivalent
to 1,100 Btu/lb of ethylene and the steam consumption is equivalent to
6,200 Btu/lb of ethylene. It is assumed that steam is generated in an
on-site oil-fired boiler and that electricity is purchased. It is
expected that oil-fired steam generators will be used in this process
consistent with the philosophy of switching from natural gas to heavy
fuel stocks. Estimated emissions — based on the emission factor of
3 lb/1,000 gal of oil burned in the boiler (AP-42) — are 0.25 Ib/ton
of ethylene. Estimated emissions from off-site power boilers are 17.6
Ib/ton of ethylene with no control, and 0.22 Ib/ton of ethylene with
control to meet the NSPS. Total emissions from boilers are estimated
at 17.9 Ib/ton of ethylene with no control, and 0.47 Ib/ton of ethylene
with control to meet the NSPS.
47
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process Option 2 - Ethylene from the Pyrolysis of Gas-Oil—
Several plants now being constructed will use gas-oil as feed.
The design of such plants is well established at the commercial level
and the practice is clearly going to become common as ethylene producers
move to assure themselves of some flexibility in their choice of feed-
stock. (A process description for ethylene production based on gas-oil
is given in Volume VI, page 27.)
The particulate emission sources and emission control methods in
this alternative are the same as in the base case process. The uncon-
trolled intermittent emission rate in the alternative process is the
same as in the base case process; however, the number of hours per year
during which emissions are produced is increased to 3,360. The reasons
for the increase in the hours is due to more build-up of coke when
gas-oil is used as a feedstock, and a higher quantity of feedstock must
be processed as compared to that in the base case process. The uncon-
trolled emissions are estimated at 0.25 Ib/ton of ethylene. The con-
trolled emission rate is 2.0 Ib/hr and is equivalent to 0.012 Ib/ton
of ethylene.
Fuel is consumed in the process heaters at a rate equivalent to
14,700 Btu/lb. Estimated emissions from this source — based on the
emission factor of 10 lb/10 cu ft of gas (AP-42) — are 0.28 Ib/ton
of ethylene.
Total uncontrolled emissions from the process are 0.53 Ib/ton of
ethylene, and the controlled emissions are estimated at 0.29 Ib/ton of
ethylene.
Electricity consumption in the alternative process is equivalent
to 1,500 Btu/lb of ethylene, and steam consumption is equivalent to
5,500 Btu/lb of ethylene. It is assumed that steam is generated in
an on-site oil-fired boiler, and that electricity is purchased. The
estimated emissions based on the emission factor of 3.0 lb/1,000 gal
of oil burned in the on-site boiler are 0.22 Ib/ton of ethylene. The
estimated emissions from off-site power boilers are 24 Ib/ton of ethylene
with no control, and 0.30 Ib/ton of ethylene with control to meet the
NSPS. Total emissions from the boilers are estimated at about 24 Ib/ton
of ethylene with no control, and 0.52 Ib/ton of ethylene with control
to meet the NSPS.
Summary
Uncontrolled and controlled particulate emission factors in the
olefin industry are summarized in Table 12, and estimated particulate
emissions are summarized in Table 13. The majority of the total
emissions — more than 65% of the controlled emissions and more than
95% of the uncontrolled emissions — come from the power boilers. These
emissions are well controlled and therefore these processes have high
overall particulate collection efficiency (> 95%). The emission sources
48
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TABLE 12. ESTIMATED PARTICIPATE EMISSION FACTORS - OLEFIN INDUSTRY
Emission factor - no control Emission factor - with control Control
(Ib/ton of ethylene) (Ib/ton of ethylene) efficiency
Process Process Power boiler Total Process Power boiler Total (%)
Base case:
Ethylene from ethane and
propane 0.22 14.6 14.8 0.15
• Ethylene from naphtha 0.33 17,9 18.2 0.20
• Ethylene from gas-oil 0.53 24.0 24.5 0.29
0.33 0.48 96.7
0.47 0.67 96.3
0.52 0.81 96.7
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TABLE 13. CONTROLLED ESTIMATED PARTICULATE EMISSIONS - OLEFIN INDUSTRY
Process
Base case:
Ethylene from ethane and
propane
• Ethylene from naphtha
• Ethylene from gas-oil
Total controlled
particulate emission factor
(Ib/ton of product)
0.48
0.67
0,81
Change in
emission factor
— —
+ 0.19
+ 0,33
Particulate
emissions
(10b Ib/yr) ^
1974 1989-1974
6.2 13.5
18.9
22.8
Ul
o
* 6
Based on production in 1989 being 28.2 x 10 ton greater than in 1974.
-------
and the emission control methods in these processes are similar. Both
the uncontrolled and controlled emission factors in the alternative
processes are higher than those in the base case process (Table 12)
when based on ethylene production; however, if the emission factors
are compared on the basis of tons of feedstock, those in the alternative
processes are lower than those in the base case process.
Although the actual quantities of particulate emissions are not
great, the particulate emissions in the year 1974, based on the ethane
and propane cracking, are 6.2 x 10 Ib/year (ethylene production, ,
13.2 x 10 ton/yr) and will increase by the year 1989 to 19.7 x 10 Ib/yr
(ethylene production, 41.2 x 10 ton/yr). If the alternative processes
are installed on the incremental production from 1974 to 1989, estimated
particulate emissions from the total production.of ethylene in the year
1989 based on the naphtha process are 25.1 x 10 Ib/yr and based on
the gas-oil process are 29.0 x 10 Ib/yr. These estimations include
emissions of 6.2 x 10 Ib/yr in the base case year (1974). The increase
in emissions which is attributable to heavier feedstocks is quite signi-
ficant; however, the alternative processes produce higher quantities of
byproducts. Emissions generated from the production of these byproducts
when added to the base case process for comparison will alter the impact
on particulate emissions; however, this overall impact is not determined
in this report.
ALUMINA AND ALUMINUM INDUSTRY
Alumina Production
Base Case Process - Bayer Process—
The Bayer process for producing alumina is based on imported bauxite.
The process includes: digestion of ground bauxite, removal of impurities,
precipitation of aluminum trihydrate, treatment of spent liquor to regen-
erate the caustic, and calcination of aluminum trihydrate to produce
pot feed alumina. A detailed description of the process is given in
Volume VIII, page 106.
Within a Bayer plant, bauxite is ground and digested with caustic
to produce sodium aluminate. The major source of emissions during this
operation is the ore grinder. The reported particulate emission factor
is 6.0 Ib/ton of bauxite (EPA 1975). Particulates from the ore grinder
are collected in a hood and removed using a high-efficiency particulate
collection device, such as an electrostatic precipitator. The expected
emissions from a precipitator are 0.12 Ib/ton of bauxite (EPA 1975).
Low-efficiency wet-collection devices have been used at some plants,
but are generally not effective enough to comply with current standards.
About 2.4 tons of bauxite are required to produce a ton of alumina
(Volume VIII, page 111). Thus estimated uncontrolled particulate
emissions are 14.4 Ib/ton alumina and controlled are 0.29 Ib/ton
alumina. After precipitation, alumina trihydrate is calcined in a
rotary kiln to produce alumina. Emissions from the kiln are reported
51
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to be 200 Ib/ton of alumina (EPA 1975). Particulates from the rotary-
kiln calcining operation are removed using a combination of multicyclone
and electrostatic precipitators or bag filters. Emissions from the
electrostatic precipitator are 4.0 Ib/ton of alumina. (EPA 1975)
In addition, emissions result from crushing and calcination of
limestone (CaCO ). About 0-133 ton of limestone/ton of alumina is
required (Volume VIII, page 111). This amounts to about 0.074 tons
CaO/ton alumina. Uncontrolled emissions are reported to be 33 Ib/ton
of lime from crushing and 200 Ib/ton of lime from the kiln. Therefore,
uncontrolled emissions are about 17 Ib/ton of alumina. Scrubbers or
bag filters can be used to control only kiln emissions with a reported
collection efficiency of up to 99 percent. Therefore, the controlled
emissions are estimated at about 2.6 Ib/ton of alumina, which are mostly
from the crusher operation.
Total process emissions from the Bayer process are about 232 Ib/ton
of alumina with no control, and controlled emissions are about 6.9 Ib/ton
of alumina.
Electricity consumption in the base case process is estimated at
275 kWh/ton of alumina, and steam consumption is estimated as equivalent
to 7.33 x 10 Btu/ton of alumina. Particulate emissions from coal-fired
power boilers are estimated at 82 Ib/ton of alumina with no control,
and about 1.0 Ib/ton of alumina with control to meet the NSPS.
Process Option 1 - Hydrochloric Acid Ion-Exchange Process—
This process includes dehydration of the raw clay, leaching with
hydrochloric acid, separation of residue, purification of the solution
by amine ion exchange, crystallization of aluminum chloride, decomposition,
and calcination to obtain alumina. (A detailed description of the process
is given in Volume VIII, page 23.) No commercial plant embodying this
process has ever been builc (Volume VIII, page 27); therefore the esti-
mated emissions represent engineering judgment.
It is estimated that this process alternative during grinding and
calcining of clay generates as much dust as does bauxite during grinding
and initial calcination (Volume VIII, page 29). Therefore, the emissions
and the control methods from these sources are the same as those in the
base case process. Lime ±s not used in this alternative, so lime-related
emissions are not present. The total process emissions are estimated
at 215 Ib/ton of alumina with no control, and 4.2 Ib/ton of alumina with
control.
The electricity consumption in this alternative is 134 kWh/ton of
alumina. Estimated emissions from power boilers are 11.3 Ib/ton of
alumina with no control, and 0.14 Ib/ton of alumina with control to
meet the NSPS.
52
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Process Option 2 - Nitric Acid Ion-Exchange Process—
This process includes calcining kaolin clay, leaching the calcined
clay with hot nitric acid, separating the clay insolubles, removing
the iron and other impurities, recovering the alumina by hydrolysis,
recovering the nitric acid, and calcining to obtain alumina. This
process is presently not used in the industry.
The calcination of beneficiated clay pellets would not generate
as much particulate matter as the calcination of bauxite, but particulate
emission controls will be required for clay particulates and fly ash,
because coal is used in the calcination kiln. Emission factors cannot
be calculated because quantitative data are not available.
Electricity consumption in this alternative is 139 kWh/ton of
alumina (Volume XIII, page 39). Estimated emissions from power boilers
are 11.7 Ib/ton of alumina with no control, and 0.15 Ib/ton of alumina
with control to meet the NSPS.
Process Option 3 - Toth Alumina Process—
This process involves the chlorination of alumina-containing raw
materials in the presence of carbon to produce aluminum chloride
vapor and other volatile chlorides, which are purified to eliminate
other metal chlorides and then oxidized to alumina and chlorine for
recycle. (The details of the process are given in Volume VIII, page 39.)
Dehydration of raw clay in a dryer and calcination in a kiln will
result in emissions containing particulates. The dryer and kiln will
require particulate control devices. Emission factors from these sources
cannot be calculated because quantitative data are not available. It
can only be presumed that particulate emissions may be comparable to
those for the drying and calcination of lime or clay, approximately
200 Ib/ton solids.
Electricity consumption in this alternative is 333 kWh/ton of alumina
(Volume XIII, page 48). Estimated emissions from power boilers are
about 30 Ib/ton of alumina with no control, and 0.35 Ib/ton of alumina
with control to meet the NSPS.
Aluminum Production
Base Case Process - Hall-Heroult Process—
This process involves reduction of alumina to aluminum using electro-
lytic cells. The existing plants use Soderberg electrodes, while the
new plants use prebaked electrodes which consume less energy. A detailed
description of the process is given in Volume VII, page 52.
53
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Plants which use Soderberg cells do not require anode furnaces,
because the anode is formed from a coke-based paste within the electro-
lytic cell itself. There are two types of Soderberg cells: horizontal
stud and vertical stud. With respect to air pollution control, the
primary difference between these two types has to do with the east
with which a hood can be placed over a cell to capture emissions.
Hood efficiency has been reported to be 50 percent for vertical-stud
cells and 80 percent of horizontal-stud cells (Volume VIII, page 136).
Uncontrolled emissions in the hood have been reported to be about 98 Ib/ton
for horizontal-stud cells and 78 Ib/ton for vertical-stud cells (AP-42).
Wet electrostatic precipitators or venturi scrubbers can be used for
particulate control. Controlled emissions from the particulate control
device have been reported to be about 7.0 Ib/ton for horizontal-stud
cells and about 3.0 Ib/ton for vertical-stud cells. With respect to
hood efficiency, uncontrolled emissions are estimated to be 123 Ib/ton
for horizontal-stud cells and 156 Ib/ton for vertical-stud cells. Total
controlled emissions are estimated to be 32 Ib/ton for horizontal-stud
cells, and 81 Ib/ton for vertical-stud cells.
Electricity consumption in the baseline process is 15,600 kWh/ton.
Estimated particulate emissions from power boilers are 1,310 Ib/ton
with no control, and 16.4 Ib/ton with control to meet the NSPS.
The emission factor for the prebake anode furnace is 3.0 Ib/ton of
aluminum, which can be reduced to 0.06 Ib/ton of aluminum by self-induced
sprays (EPA, 1975). The emission factor for the prebake cell is 81.3
Ib/ton of aluminum. Emissions can be controlled by coated filters,
electrostatic precipitators, or by dry alumina adsorbers to 1.62 Ib/ton
of aluminum (EPA, 1975).
Captive efficiency of the hood on the prebake cell is reported to
be 95 percent on new cells (Volume VIII, page 136). Therefore, the
uncontrolled process emissions from the cell and prebake furnace are
estimated at about 89 Ib/ton, and the controlled emissions are estimated
at about 6.0 Ib/ton.
Electricity consumption in the new cells is estimated at 12,000 kWh/ton.
Estimated paritculate emissions from power boilers are about 1,010 Ib/ton
with no control, and about 12.6 Ib/ton with control to meet the NSPS.
Process Option 1 - Alcoa Chloride Process—
This process starts with pot feed alumina from the Bayer process.
The alumina is converted into aluminum chloride by chlorination in the
presence of carbon to form volatile aluminum chloride. This, in turn,
is purified and fed to the electrolytic cells to produce molten aluminum.
A detailed process description is given in Volume VIII, page 57.
54
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The process emissions include emissions from the dryer calciner and
electrolytic cells. Currently, there are no plants in operation, so
data on emissions from those sources are not available. The nature of
the process is so different- that it would be unrealistic to attempt
estimates based on the very sparse information available.
Electricity consumption in this process is 10,500 kWh/ton (Volume
VIII, page 69). Estimated particulate emissions from power boilers are
about 882 Ibs/ton with no control, and about 11 Ib/ton with control
to meet the NSPS.
Process Option 2 - Refractory Hard Metal Cathodes Process—
This process is based on Bayer alumina and uses titanium diboride
cathodes instead of conventional carbon cathodes. The cathodes are
assumed to be retrofitted in existing large cells to increase production
and reduce energy consumption (Volume VIII, page 74). A detailed process
description is given in Volume VIII, page 68.
The uncontrolled emissions, emission control system, and controlled
emissions from this alternative process are expected to be the same as
in the base case process with Soderberg cells. Electricity consumption
is estimated at 12,480 kWh/ton (Volume VIII, page 74). Estimated
particulate emissions from the power boiler are about 1,050 Ib/ton
with no control, and about 13.1 Ib/ton with control to meet the NSPS.
Process Option 3 - Combination of the Clay Chlorination Process and
the Aloca Chloride Process—
This combined process has all of the emission problems of the Toth
alumina process, plus some of the problems of the Aloca process. The
details of the combined process are given in Volume VIII, page 79.
Emissions from this alternative process cannot be estimated, because
data are not available for the separate processes. Electricity con-
sumption is estimated at 10,637 kWh/ton (Volume VIII, page 81). Estimated
particulate emissions from power boilers are about 895 Ib/ton with no
control, and about 11.2 Ib/ton with control to meet the NSPS.
Summary
Currently, the Hall-Heroult process relies heavily on hydroelectricity
(^ 25%). Since availability of hydroelectric power is projected to be
limited, especially for increased production capabilities, the entire
study has been carried out assuming fossil fuel-derived power.
The particulate emission factors from the base case and the alter-
native processes in the alumina and aluminum industry are shown in
Table 14. The uncontrolled emission factor in the hydrochloric ion-
exchange process for alumina production is about 28% lower than in the
corresponding base case process, because the electricity consumption in
the alternative process is lower than that in the base case process.
55
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TABLE 14. ESTIMATED CONTROLLED PARTICULATE EMISSION FACTORS -
ALUMINA AND ALUMINUM INDUSTRY
Emission factor - no control Emission factor - with control Control
Process
Base case:
Bayer
• Hydrochloric acid
ion exchange
• Nitric acid ion
exchange
• Clay chlorination
(toth)
Aluminum
Base case:
Hall-Heroult (current
practice)
• Hall-Heroult (new)
• Alcoa chloride
• Refractory hard metal
cathode
Base case:
Bayer and Hall-Heroult
(C.P.)
• Toth alumina and alcoa
chloride
(Ib/ton product)
Process Power boiler Total
232.0
215.0
N.A.
N.A,
123-156
89
N.A.
123-156
355-388
N.A.
82.0
11.3
11.7
30.0
1310
1010
882
1050
1392
895
314,0
226.3
N.A.
N.A.
1433.0-1466.
1099
N.A.
1173-1206
1747-1780
N.A.
(Ib/ton product) efficiency
Process Power boiler Total (%)
6,7
4.3
N.A.
N.A,
0 32-81
6
N.A.
32-81
38.7-89.7
N.A.
1.0 7.7 97.5
.14 4.4 98.0
.15 N.A. N.A.
.35 N.A. N.A.
16.4 48.4-97.4 93.3-96.6
12.6 18.6 98.3
11 N.A, N.A.
13.1 45.1-94.1 92.2-96.1
17.4 56.1-105.1 94.1-96.8
11.2 N.A. N.A,
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TABLE 15. ESTIMATED PARTICULATE EMISSIONS - ALUMINA AND ALUMINUM INDUSTRY
Ul
Total controlled
particulate emission factor
Particulate
emissions
Process
Alumina
Base case:
Bayer
• Hydrochloric acid ion exchange
• Nitric acid ion exchange
• Toth alumina
Aluminum
Easy case:
Hall-Heroult (current practice)
• Hall-Heroult (new)
• Aloca chloride
• Refractory hard metal cathodes
(Ib/ton of product)
7.7
4.4
N.A.
N.A.
48.4-97.4
18.6
N.A.
45.1-94.4
Change in
emission factor
-
- 3.3
N.A.
N.A.
-
- 29,8 to -78.8
N.A.
- 3.3
(10° Ib/yr)
1974** 1989-1974*
59.3 83.2
47.5
N.A.
N.A.
242-487 338.4-681.8
130.2
N.A.
315.7-660.8
• Combination of clay chlorination
and the aloca chloride N.A.
Base case:
Bayer and Hall-Heroult (c.p.) 63.2-112.3
• Clay chlorination and alcoa chloride N.A.
N.A.
N.A.
N.A.
356-601 499-842
N.A.
(continued)
-------
**
TABLE 15. (continued)
Based on production in 1989 being 10.8 x 10 tons of alumina, or 7 x 10 tons of aluminum, greater
than in 1974.
Estimated 1974,emissions (based on the emission factor of 7.7 Ib of particulates/ton of alumina) are
7.7 x 7.7 x 10 = 59.3 x 10 Ib of particulates from alumina production; and (based on the controlled
emission factor of 48.4 to 97.4 Ib of particulates/ton of aluminum) are 48.4 x 5 x 10 = 242 x 10
to 97.4 x 5 x 10 = 487 x 10 Ib of particulates from aluminum production.
Ul
oo
-------
Similarly, the controlled emission factors for the alternative
processes for aluminum production are lower than those for the corres-
ponding in the alternative processes and increased collection efficiency
of hoods in the Hall-Heroult process based on prebake cells. Particulate
emissions for the alumina and aluminum industry are shown in Table 15.
Clearly there is insufficient data in several of the processes from
which to draw conclusions concerning the significance of particulate
emissions to industry decisions. Further, some of the processes are
grossly different in character and the particulates generated may also
be different; unfortunately it is not currently possible to predict
whether such differences (if they exist) will simplify or complicate
removal.
Based on the analysis carried out on the original study (Volume VIII),
the alternative alumina processes will not offer energy advantages. They
are, however, based on domestic resources which might have to be called
upon in the future.
CEMENT INDUSTRY
Base Case Process - Long Dry Rotary Kiln
The base case process selected for the cement industry was the long
dry rotary kiln. Hydraulic cement is a powder made by burning lime,
silica, alumina, iron, and magnesia together in a kiln and then pul-
verizing the product. The production of finished cement from raw
materials involves four steps: crushing, grinding, clinkering, and
finish grinding. Dry grinding is used in the dry process. This is
very much like wet grinding, except that no water is added and the
material is ground dry, usually at 1% moisture content or less. (A
detailed description of the process is given in Volume X, page 84.)
The major source of particulate emissions in a cement plant is
the kiln. Dust is generated in kiln operations by the hot combustion
gases entraining feed particles. Also involved in the tumbling action
within the kiln, the liberation of gases during calcination (which tends
to expel particles into the gas stream), and the condensation of material
that is volatilized at the firing end of the kiln. Volatilization and
condensation generally produce smaller particles than the mechanical
processes, thereby increasing the difficulty of removal for the air
pollution cleaning system.
As clinker is discharged from the lower end of the kiln, it is
passed through a clinker cooler that reduces the temperature of the
clinker. The clinker cooler represents another source of airborne
pollutants. The exhaust gas from the cooler may be used as combustion
air in the kiln. In this case, cooler will not be a source of particulate
emissions.
59
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Emissions from the crusher area depend on the type and moisture
content of the raw material and the type and characteristics of the
crusher. If the material has a high moisture content, there may be
little emissions, so it may not be necessary to provide dust control.
In a wet-process plant, the performance of an electrostatic pre-
cipitator is greatly enhanced by the extra water vapor in the exhaust
gases from the slurry. Dry-process kilns do not have water in the feed,
so it is often necessary to add water as an aid to the precipitator
operation. In the past, the operation of electrostatic precipitators
has not been entirely satisfactory, because of decreasing efficiency
over extended periods due to the effects of the cement dust on the high-
voltage components. Also, when kilns have been shut down and then
restarted, it has been necessary to bypass the electrostatic precipitator
for periods of up to 24 hours, because of the danger of explosion from
combustible gas or coal dust.
Fiberglass bag filters have had much success in controlling kiln
emissions. Bag life averages 18 months or more. Also in baghouse
installations, duct designs are simple and uncomplicated, requiring
little study for the flow of gases compared with the frequently compli-
cated model studies necessary for good gas-flow patterns in the
electrostatic-type dust collector.
Moisture condensation in glass-fabric filters can present problems.
However, dew point temperatures are normally avoided by proper appli-
cation of insulation to ducting, etc., and by proper operation to avoid
condensation.
Uncontrolled emissions from the long dry kiln are 245 Ib of parti-
culate/ton of cement (AP-42). Emissions can be controlled in bag
filters (collection efficiency 99.8). The lower efficiency of multi-
cylcones (80%) and electrostatic precipitators (95%) may not be accep-
table for new plants. Estimated emissions from bag filters are less
than 0.5 Ib/ton of cement. For the purposes of this study, it is pre-
sumed that the kiln is fired with gas or oil, but not coal. In any
case, since clinkering is a direct fired process, the emissions commingle
with the process particulates.
Electricity consumption in the base case process is equivalent to
1.6 x 10 Btu/ton of cement (Volume X, page 30). Estimated emissions
from power boilers are 12.8 Ib/ton of cement with no control, and
0.16 Ib/ton of cement with control to meet the NSPS,
Process Option 1 - Suspension Preheater Process—
The suspension preheater is a modification of, or addition to, the
cement rotary kiln. It is attached to the raw feed inlet end of the
kiln, and totally replaces the preheating zone. The suspension preheater
reheats the raw material and also accomplishes a considerable amount of
raw material calcination. Typical suspension preheaters heat cold raw
60
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feed to approximately 1,400°F (760°C) and accomplish 30 to 40% of the
total calcination or thermal decomposition of the calcium carbonate,
the main component of the raw feed. Consequently, with the suspension
preheater, the rotary kiln receives hot and partially calcined raw
material. (There are several variations on the suspension preheater
and these are described in Volume X, page 19.)
One of the environmentally advantageous aspects of the suspension
preheater is its ability to trap the alkalies and sulfur values within
the lower and higher temperature stages of the preheater. These alkalies
remain with the cement clinker. In some cases, this may not be acceptable
because of the alkalies present in the cement (product quality is affected
by the presence of alkalies). Therefore, a four-stage suspension pre-
heater, operating with no bypass, would send to the dust-collecting system
a relatively cool combustion gas stream containing solid particulate
material which is physically and chemically similar to cement raw feed
and can, usually, be recycled.
Uncontrolled emissions from this alternative design cannot be esti-
mated, because a suspension preheater removes some of the particulate
matter. If bag filters are used for particulate control, the outlet
concentration will be comparable to that in the base case process.
The estimated controlled emissions are then 0.35 Ib/ton of cement.
The electricity consumption in this alternative process is equivalent
to 1.32 x 10 Btu/ton of cement (Volume X, page 30). The estimated
emissions from the power boiler are 10.6 Ib/ton of cement with no control
and 0.13 Ib/ton of cement with control to meet the NSPS. This option
conserves considerable energy and also reduces loss of material as
particulates.
Process Option 2 - Flash Calciner Process—
Although the designs of flash calcining systems vary, the main
feature which characterizes the flash calciner rotary kiln is the flash
calcining vessel added between the rotary kiln and the suspension
preheater. A detailed process description is given in Volume X, page 34.
The flash calciner arrangement (described in Volume X, page 23)
requires a considerable amount of excess combustion air in burning
the fuel in the rotary kiln so that enough air is present in the com-
bustion gases leaving the kiln to permit combustion of the fuel in
the flash calcining vessel. The quantity and dust loading of the com-
bustion gas stream leaving a flash calciner should be essentially the
same as for a comparable suspension preheater; however, there are no
data in the available literature to clarify this. The difference would
be in the gases leaving through a bypasss. If bag filters are used
for particulate control, the outlet concentration may be the same as
that in the base case process. Estimated controlled emissions are
0.35 Ib/ton of cement.
61
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The electricity consumption in this alternative is the same as in
the suspension preheater alternative. Estimated emissions from power
boilers are 10.6 Ib/ton of cement with no control, and 0.13 Ib/ton of
cement with control to meet the NSPS,
Process Option 3 - Fluidized-Bed Cement Process—
The only difference between the fluidized-bed, cement-making
process and the conventional process is the high-temperature clinkering
step. All of the other steps are essentially identical. A detailed
description of the process is given in Volume X, page 40. The energy
consumption in the fluidized bed is about 10% higher than the long
kiln (Volume X, page 46). However, there is a net electricity generation
in the fluidized bed process.
The composition of the solid particulates carried from the fluidized-
bed cement reactor is very different from that of rotary kiln dust.
Rotary kiln dust consists of partially calcined cement raw feed and
potassium and sodium sulfates in the range of 5-10% total alkalies,
expressed as the stoichiometric equivalent of sodium oxide. In contrast,
it is reported that the solid particulates carried by the hot combustion
gases existing the fluidized-bed cement reactor consist of 97% water-
soluble potassium and sodium sulfates, and only 3% cement clinker.
Therefore, since the dust from the fluidized-bed process is essentially
pure potessium and sodium sulfate, the quantity of dust collected per
ton of cement clinker produced is very small compared with the dust
collected from the conventional rotary kiln process.
Alkali compounds emitted with the effluent gases from the fluidized
bed are estimated to be 50 Ib/ton of clinker product (Volume X, page 43).
Controlled emissions are estimated to be 0.75 Ib/ton of cement, based
on an estimated collection efficiency of 98.5%.
There is a net electricity generation in this alternative (Volume X,
page 46). The estimated emissions at the power boiler which are off-
set by this generation are 1.2 Ib/ton of cement with no control, and
0.015 bl/ton of cement with control to meet the NSPS.
Process Option 4 - Conversion to Coal Fuel from Oil and Natural Gas—
The process using coal as a fuel in the cement kiln is described
in Volume X, page 60. Particulate emissions from the process and power
boiler are not affected by switching the fuel from oil or natural gas
to coal. Direct firing allows the coal ash to be incorporated in the
clinker to between 50 and 100%. The remainder is removed along with
the cement dust (see Volume X, page 70).
62
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Summary
The particulate emission factors for the cement industry base case
process and the process alternatives are summarized in Table 16. Uncon-
trolled emission factors are highest for the long dry kiln, based on gas,
oil, or coal as fuel. Uncontrolled emissions from the fluidized bed
are lowest.
Emissions from the cement manufacturing processes can be controlled
by bag filters. Controlled emission factors are also shown in Table 16.
Controlled emission factors for the alternative processes are 15 to 30%
lower than for the base case process, except for the alternative in which
coal is used as a fuel. Particulate emissions for the processes studied
are summarized in Table 17.
As noted earlier, the properties of the dust may have a marked effect
on its removability as well as upon its ecological impact. Chemical com-
position and size distribution (see Volume II, Table IV-13, page 76) may
be expected to change over the years as other processes become important.
GLASS INDUSTRY
Base Case Process - Regenerative Furnace
The base case process selected for study was the natural gas-fired
furnace with cold charge. (A detailed description of the furnace is
given in Volume XI, page 17.) Operating conditions for the base case
process are:
Furnace type: Side port, regenerative
Fuel: Natural gas
Glass type: Soda lime
Plant location: East North Central
Pull Rate: 200 tons per day
Feed Rate: 240 tons per day
Efficiency: 90%, or 180 tons per day
A typical glass melting operation is described in detail in Volume
XI, page 19. A glass melting furnace has both particulate and gaseous
emissions which must be controlled.
The uncontrolled particulate emission factor for the glass furnace
is 2.0 Ib/ton of glass (AP-42). More than 90% of the particles are
less than 0.6 microns in diameter, and about 50% are less than 0.1 micron
in diameter (Volume XI, page 28), making these emissions some of the most
difficult to control.
High pressure drop scrubbers (AP = 65 inches WG) have been reported
to remove only 95% of the particles. Conventional electrostatic pre-
cipitators have collection efficiency limits similar to those of wet
scrubbers.
63
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TABLE 16. ESTIMATED PARTICIPATE EMISSION FACTORS - CEMENT INDUSTRY
Emission factor - no
Process
Base case:
Long dry rotary kiln
• Suspension preheater
• Flash calciner
• Fluidized bed
control Emission factor - with
(Ib/ton of cement)
Process Power boiler Total
245
N.A.
N.A.
50
12.8
10,6
10.6
- 1.2
257.8
N,A.
N.A.
48.8
control
Control
(Ib/ton of cement) efficiency
Process Power boiler Total (%)
0.5
0.35
0.35
0.75
0,16
0.13
0.13
- 0,01
0.66
0.48
0.48
0.74
99.7
-
-
98.5
• Coal as fuel instead of
gas or oil in long dry
kiln
245
12.8
257.8
0.5
0.16
0.66
99.7
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TABLE 17. ESTIMATED PARTICULATE EMISSIONS - CEMENT INDUSTRY
Process
Base case:
Long dry rotary kiln**
• Suspension preheater
• Flash calcine r
• Fluidized bed
• Coal as fuel instead of gas or
oil in long dry kiln
Total
particulate
Ib/ton of cement)
0.66
0.48
0.48
0.74
0.66
controlled
emission factor
Change in
emission factor
-
- 0.18
- 0.18
+ 0,08
0
Particulate
emissions
(10° Ib/yr)
1974** 1989-1974*
52.1 18.0
13.1
13.1
20.2
18.0
Based on production of cement in 1989 being 27.3 x 10 tons greater than in 1974.
The particulate emissions (based on the emission factor of 0.66 Ib/ton of cement in the year 1974)
are 0.66 x 79 x 10 = 52.1 x 10 Ib/yr.
-------
Emissions from very few of the glass melting furnaces in the United
States are currently controlled, because of the difficulty of control.
The operating problems include corrosion because of chemicals containing
boron, sulfur, and fluorine, as well as plugging and solids deposition.
Presence of condensable particulates is also a problem in the use of
precipitators and bag filters operating at high temperatures, because
the particulate loading downstream of the control device is increased
due to condensation. There is no typical air pollution control system
readily available to serve as a basis for estimating collection efficiency,
It is estimated that particulate removal efficiency of about 95% will
be required to meet operating standards, so a controlled emission factor
is estimated at 0.1 Ib/ton of glass. In many cases, even though this
standard can be met, it is difficult to meet opacity standards.
The electricity consumed in the base case process in 19 kWh/ton
of glass (Volume XI, page 31). Estimated emissions from power boilers
are 1.6 Ib/ton of glass with no control, and 0.02 Ib/ton of glass with
control to meet the NSPS as shown in Table 18.
Process Option 1 ~ Coal Gasification—
Coal gasification processes include, in some variation, the
following steps: coal handling and storage, coal preparation, gasifi-
cation, oxidant feed facilities, and gas cleaning. The gas produced
from coal gasification is used as a fuel source in the glass furnace.
The details of the process are given in Volume XI, page 32.
When coal gasification is used to generate the gaseous fuel for
the glass melting furnace, the major environmental difference is not
in the glassmaking process, but rather in the fuel-generating process.
Typically, the gas produced in the coal gasifier will contain parti-
culates. Cyclones used for removal of tar from the gas will remove
some of the particulates. However, the particulate collection efficiency
of the cyclone is low, so the gas entering the glass furnace will not
be free of particulates. There are no effluent gases (waste) in the
gasification process and therefore it does not create any particulate
emissions.
Particulate emissions from the glass furnace will increase over
the base case in this alternative, because the fuel gas used for heating
the glass contains particulates and also the exhaust gas volume is about
10% higher than that in the base case process. Uncontrolled emissions
in this alternative cannot be estimated, because no data are available.
The control equipment used in this alternative is the same as in
the base case process, except that the equipment used in this alternative
will be physically larger because of the increase in gas volume, Con-
trolled emissions will be slightly higher than those in the base case
process.
66
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TABLE 18. ESTIMATED PARTICULATE EMISSION FACTORS - GLASS INDUSTRY
Process
Base case:
Regenerative furnace
• Coal gasification
• Direct coal firing
• Coal fired hot gas
generation
• Electric melting
• Batch preheat with
natural gas firing
«
Emission factor - no
control Emission factor - with
control Control
(Ib/ton of glass) (Ib/ton of glass) efficiency
Process Power boiler Total Process Power boiler Total (%)
2.0 1.6
> 2.0b 1.6
> 2.0b 1.6
V,
N.A. 1.6
« 2.0b 65.5
< 2'° 1.6
3.6 0,1
> 3.6 * O.lb
> 3.6 > 0,lb
b
N.A. N.A.
* 65.5 « 2.0b
< 3,6 ^ O.lb
0.02
0.02
0.02
0.02
0.82
.02
.12 96.7
^ .12
> .12
N.A.
^ .82
^ .12
Reported as Ib particulate/ton of glass
See text
N.A. - not available
-------
The electricity consumed in this alternative is the same as in the
base case process, so emissions from power boilers will be identical
as indicated in Table 18.
Process Option 2 - Direct Coal-Firing Process—
In this option, pulverized coal is used directly in burners to
supply the energy. (The details of the process are given in Volume XI,
page 45.)
Particulate emissions from this alternative will be higher than
those from the base case because coal combustion generates more parti-
culates than gas combustion, and also the exhaust gas volume is about
15% higher in this alternative than that in the base case process. The
uncontrolled emission factor cannot be estimated, because no data are
available. The maximum increase in the particulate emissions will be
equal to that generated from the coal combustion. Based on 12% ash
in coal and the coal consumption rate of 62 ton/day (Volume XI, page 45),
the maximum emissions from coal combustion are 75 Ib/ton of glass.
The particulate control equipment used in this alternative is the
same as in the baseline process, except that the equipment will be
physically larger. Controlled emissions will be higher than those in
the base case process.
The electricity consumed in this alternative is the same as in
the base case process, so emissions from power boilers will be identical
as shown in Table 18.
Process Option 3 - Coal-Firect Hot Gas Generation (COHOGG) Process Alternative
This system generates a hot gas by separating char and volatiles,
burning the char, and then mixing the products of combustion with the
volatiles and burning them together. A pneumatic conveying system feeds
powdered coal to the pyrolyzer along with limestone or a mixture of lime-
stone and sodium chloride. The outlet temperature of the gases leaving
the afterburner is 3,000°F. These hot gases are used in the glass
melting furnace to heat the glass batch. The details of the process are
given in Volume XI, page 48.
There is no difference bewteen the coal gasification alternative
and that of heating the glass-melting furnace with a hot combustion gas,
except the gas volume from the glass furnace is 25% higher with the
COHOGG process because of the efficiency losses inherent in the system.
The particulate emission factor will be higher for this alternative than
that for the coal gasification alternative. The pollution control system
will be the same as in the base case process, except that the equipment
will be larger.
68
-------
The electricity consumed in this alternative is about the same as
in the base case process, so emissions from power boilers will be much
the same as indicated in Table 18.
Process Option 4 - All-Electric Melting Alternative—
Glass can be heated and melted with electric current. Both the
design and the operation of an all-electric, glass-melting furnace differ
greatly from those of the typical natural gas-fired regenerative furnace.
The electric furnace without regenerative checker structure is a much
simpler design. The details of the electric furnace are given in
Volume XI, page 53.
In this case, the only exhaust from the glass-melting furnace is
from decomposition of carbonates, sulfates, nitrates, etc., in the glass
batch. The exhaust is almost entirely CO with some SO . Data on the
particulate emissions from this alternative are not available; however,
the magnitude of emissions can be realized by comparing emissions from
the gas-fired and electric fiberglass furnaces. In the wool fiberglass
industry, the emissions from the gas-fired regenerative furnace are
21.5 Ib of particulates/ton of fiberglass and the emissions from the
electric furnace are 0.6 Ib of particulates/ton of fiberglass (AP-42).
Similarly, the emissions in this alternative process will be significantly
lower than the 2.0 Ib/ton of glass reported for the gas-fired furnace.
A pollution control system will not be required, because the emissions
are very low in this alternative.
The electricity consumption in this alternative is 780 kWh/ton
of glass (Volume XI, page 56). Estimated emissions from the power
boiler are 65.5 Ib/ton of glass with no control, and 0.82 Ib/ton of
glass with control to meet the NSPS as shown in Table 18.
Process Option 5 - Batch Agglomeration/Preheating Alternative—
Batch preheating is an energy-conserving technology relating to a
process modification rather than a method of furnace heating. Hence,
this technology is applicable to all of the previously discussed methods
of glass making. The details of the process are given in Volume XI,
page 58. The gas from the glass furnace is used to preheat the fuel
materials. The effect of this operation on particulate emissions is
not available; however, particulates generated from the preheater are
usually large (> 1.0 micron) which can be controlled easily, so the
controlled emissions will not be affected.
By improving the thermal efficiency of the furnace, this technology
reduces the fuel requirement per ton of glass, thereby reducing the
exhaust volume from the glass-melting furnace by 20%. Uncontrolled
emissions from this alternative will be less than those in the base
case process. The pollution control system will be the same as in the
base case process, except that the equipment will be smaller.
69
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The electricity consumed in this alternative is the same as in the
base case process, so emissions from the power boilers will be identical.
Summary
The particulate emission factors for the base case and alternative
processes are of the same order, except that the emissions from the
electric furnace are significantly higher when the coal-fired power
plant generating the electricity is included (Tables 18, 19). Table 19
shows a summary of estimated national emissions for 1974 and 1989 based
on the industry growth rates shown in Table 1. Emission factors in
the alternative processes can only be very roughly estimated for
comparative purposes, because of the non-availability of data, clearly
reflecting a need to carry out R&D studies of particle size, characteris-
tics, ease of removal, and cost of removal.
Control of particulates continues to be a major problem for the
industry but so too will be uninterrupted fuel supplies, particularly
natural gas. Consequently, confirmation that one or more of the alter-
nate processes can be employed without even more serious environmental
consequences will be of great help in maintaining a viable industry.
PHOSPHORUS/PHOSPHORIC ACID INDUSTRY
Base Case Process - Electric Furnace Production of Phosphorus and
Conversion of Phosphorus to Phosphoric Acid
Conversion of phosphate rock to elemental phosphorus involves
calcination in a direct fired rotary kiln, screening, and reduction
of phosphate rock to elemental phosphorus in an electric furnace. A
detailed description of the process is given in Volume XIII, page 23.
Air pollution control is a significant problem in a phosphorus
plant. The importance of handling dusty streams in the phosphorus
plant is illustrated by the need to remove dust generated from proces-
sing raw materials (phosphate rock, coke, and silica) at a rate more
than 10 times that of the product. These particulates are produced
particularly in the high-temperature rotating kiln, but they also escape
from conveyors, etc. They are usually finely divided and contain some
carbon and fluorides. However, removal of particulates can be carried
out in conventional air pollution control equipment such as cyclones,
fabric filters, or electrostatic precipitators. Although dry particu-
late control systems are widely used, one air stream that requires
scrubbing is that from the kiln, because it contains fluorides, such as
HF or SiF • which can be easily removed in a wet-scrubber. Because of
the conversion problem and reaction of fluorides with glass, precipi-
tators or filter bags are generally not used for this application.
The uncontrolled particulate emissions from this process are 40 Ib/ton
of Ca (P0,)2 from calcination, and 2 Ib/ton of Ca.,(PO,)2 from each
70
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TABLE 19. ESTIMATED CONTROLLED PARTICULATE EMISSIONS - GLASS INDUSTRY
Particulate emission factor for
Process
Base case: ,
Regenerative furnace
• Coal gasification
• Direct coal firing
• Coal-fired hot gas
generation
• Electric melting
• Batch preheat with
natural gas firing
(Ib/ton of
Process Boiler
0.1 0.02
^ 0.1 0.02
> 0.1 0.02
N.A.b 0.02
« 2.0b 0.82
* O.lb .02
glass)
Total
.12
^ .12
> .12
N,A.
^ .82
'x- .12
glass production
Change in
emission factor
^ 0
N.A.
N.A.
^ + ,70
^ 0
particulate
emissions
(10° 1/byr)
1974 1989-1974
3.5b 1.6
^ 1.6
> 1.6
N.A.
^ 10.7
* 1.6
Based on increment in production from 197401989 = 13 x 10 ton/yr. (see table 1)
Estimated 1974 emissions, based on the total emission factor of 0.12 Ib particulate/ton of glass,
are 0.12 x 29 x 10 = 23.5 x 10 Ib/yr.
N.A. - not available
-------
material handling and grinding operation. The emissions are equivalent
to about 87 Ib/ton of P~0,- from calcination and 4.4 Ib/ton of P?0 from
each materials handling and grinding operation (Midwest Research Institute,
1971); total emissions are about 96 Ib/ton of product. The expected
scrubber efficiency is 95% and the efficiencies of dry collectors
(Midwest Research Institute, 1971) for materials handling and grinders
are 90% and 97%, respectively. Therefore, the estimated total controlled
emissions from the process are 4.9 Ib/ton of P^O,-' The particulates
are, as noted, also contaminated in the carbon and fluorides.
Effluent gases from the electric arc furnace contain phosphorus
gas, carbon monoxide, and particulates. The particulates are removed
in an electrostatic precipitator before condensing the phosphorous for
process reasons; therefore, these emissions are not included in the
above estimates.
The electricity consumed in the production of phosphorus is 13,000
kWh/ton of phosphorus (P,). The estimated particulate emissions from
power boilers are about 476 Ib/ton of P?0,. with no control, and about
6 Ib/ton of P 0 with control to meet tfie NSPS.
Process Option 1 - Chemical Cleanup of Wet-Process Phosphoric Acid—
There are a number of impurities in wet-process phosphoric acid
which make it unsuitable for certain uses. Acid produced by the wet
process is purified in this alternative to the degree necessary for
production of sodium tripolyphosphate (Volume XIII, page 48). There
are no air emissions from this purification process. The electricity
consumption in the purification process is low, so the emissions are
negligible. Therefore, the total emissions in the wet-process phosphoric
acid, plus chemical cleanup, are quite similar to those present in
the wet-process phosphoric acid (discussed below).
Wet-process acid is produced by treating phosphate rock with sul-
furic acid. Phosphoric acid is formed, calcium sulfate is precipitated
and filtered off, and the acid is concentrated. All the wet-process
acid produced is used in the manufacture of fertilizers. A detailed
description of the process is given in Volume XIII, page 35.
Particulate emissions from wet-process phosphoric acid manufacture
consist of rock dust, fluoride gases, particulate fluoride, and phos-
phoric acid mist, depending on the design and condition of the plant.
Fluorine exists as various compounds in the collection equipment;
as fluorides, silico-fluorides, silicon tetrafluoride, and mixtures
of the latter and hydrogen fluoride, the mole ratio of which changes
in the vapor with the concentration of fluorosilicate in the liquid
and with temperature. Because of the complex chemistry, the composition
of emissions is variable.
72
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The reactor, where phosphate rock is decomposed by sulfuric acid,
is the main source of atmospheric contaminants. Acid concentration by
evaporation provides another source of fluoride emissions. The filter
is a third source of fluoride emissions. Emissions from filters are
not large and can be controlled by the use of hoods, vents, and scrubbers.
In addition to these three main sources of emissions, there are many
miscellaneous minor sources. These include vents from such sources
as acid splitter boxes, sumps, and phosphoric acid tanks. Collectively,
these sources of fluoride emissions are significant, so they are often
enclosed and vented to a suitable scrubber.
The particulate loading in the gas from the reactor is 0.5-3.5 gr/scf
and that from the filter is 0.017 gr/scf. The paticulates are mostly
fluoride compounds and include acid mist. Electrostatic precipitators
or bag filters are not desirable as control devices because of the
corrosion, plugging, and solids settling problems.
Uncontrolled particulate emissions from the wet process for
production of phosphoric acid are 48 Ib/ton of P 0 (EPA, 1975), These
emissions are controlled in scrubbers having 95% collection efficiency.
Therefore, the estimated controlled emissions are 2.4 Ib/ton of P 0 .
Electricity consumption in wet-process phosphoric acid production
plus chemical cleanup, is about 266 kWh/ton of P?0c (16 kWh/ton for
chemical clean up). The estimated emissions at the power boiler are
22.3 Ib/ton of P 0 with no control, and .3 Ib/ton of P 0 with control
to meet the NSPS7 ^
Process Option 2 - Solvent Extraction Cleanup of Wet-Process Phosphoric Acid—
Cleanup of wet-process phosphoric acid is based on the fact that
phosphoric acid can be transferred from solution in an aqueous phase
to solution in an organic phase, such as normal butanol, and leave
behind undesirable impurities, such as calcium chloride, in the aqueous
layer. The organic phase can then be contacted in a separate unit with
fresh water to yield a pure solution of phosphoric acid. A detailed
process description is given in Volume XIII, page 60.
It is desirable that the phosphate rock be calcined prior to
digestion. This process step is the same as that in the base case
process for production of phosphorous in the electric furnace. There-
fore, emissions present in the base case process (96 Ib/ton of P 0 with
no control and 4.9 Ib/ton of P-O with control) are present in the
calcination step of this alternative. While the emissions from the
solvent extraction cannot be quantified, they should be comparable
to those from the wet process for phosphoric acid production (48 Ib/ton
of J^s witn no control and 2.4 Ib/ton of P2°c: with control). Therefore,
the total process emissions from the alternative process are 144 Ib/ton
of P?0c with no control, and 7.3 Ib/ton of P?0,. with control.
73
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The solvent-extraction process requires steam equivalent to about
10 x 10 Btu/ton of P 0 and electricity equal to 300 kWh/ton of P2°s'
Estimated particulate emissions from the power boiler are 105 Ib/ton
of P-0 with no control, and 1.3 Ib/ton of P~°r with control to meet
the NSPS.
Process Option 3 - Strong Acid Process—
Particulate emissions from the strong acid process were not esti-
mated in the phosphorus industry report. However, we would expect
particulate emissions from this process to be of the same order of
magnitude as conventional wet-process phosphoric acid route which was
discussed above under process option 1.
Summary
The estimated particulate emission factors for the phosphorus and
phosphoric acid production processes are shown in Table 18. Uncontrolled
emissions in the wet-process phosphoric acid plus chemical cleanup,
alternative are considerably lower than in the base case process, because
this process is wet and does not consume large quantities of electricity.
In the solvent extraction alternative, uncontrolled process emissions
are higher but the total emissions are lower because the consumption of
electricity and therefore boiler emissions are low.
Dry collectors and wet scrubbers are used for particulate collection.
Controlled emission factors shown in Table 18 vary from about 2 Ib/ton
of P?0 to 11 Ib/ton of P^OC- Emissions in the alternative processes are
20-80% lower than those in the base case process. Particulate emissions
for the phosphorus and phosphoric acid industries are shown in Table 19
as they would be reflected nationally by shifts in processes over the
coming years.
From both particulate emissions and energy viewpoints, either alter-
nate process would offer great advantage, with the chemical cleanup being
the more attractive. However, both processes also face other environmental
problems which must still be resolved. Although the industry is not nearly
so large as others, such as steel or petroleum refining, and its parti-
culate emissions are also not of the same magnitude, certain problems,
such as that of fluorides, suggest that control of the industry's parti-
culate emissions should receive more than proportionate attention.
Based on the production of 1.4 x 10 ton to p2<;5/'yr in 197^> estimated
emissions from the base case process are 15.3 x 10 Ib/yr, and are expected
to increase go 22.2 x 10 Ib/yr in 1989 based on the total production rate
of 2.03 x 10 ton of P.O /yr. If the wet process phosphoric acid, plus
chemical cleanup, is installed on the incremental production from 1974 to
1989, the total emissions in 1989 would be only 17.0 x 10 Ib/yr, or if
the solvent extraction process is installed on the incremental production
from 1974 to 1989, the total emissions in 1989 would be 20.7 x 10 Ib/yr.
This suggests that alternative processes should be encouraged in this
industry.
74
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TABLE 20. ESTIMATED PARTICIPATE EMISSION FACTORS - PHOSPHORIC ACID INDUSTRY
Emission factor - no control Emission factor - with control Control
(Ib/ton of P2CV (lb/ton of ^^ efficiency
Process Process Power boiler Total Process Power boiler Total (%)
Base case:
Electric furnace 96 476 572,0 4.9 6 10.9 98.1
• Wet-process phosphoric
acid plus chemical group 48 22.3 70.3 2.4 .3 2.7 96.1
• Solvent extraction cleanup
of wet-process phosphoric
acid 144 105 249.0 7.3 1.3 8.6 96.5
Ul
-------
TABLE 21. ESTIMATED PARTICULATE EMISSIONS - PHOSPHORIC ACID INDUSTRY
Process
Total controlled
particulate emission factor
Change in
(Ib/ton of P>,0r) emission factor
Particulate
emission
(106 Ib/yr)
1974**
1989-1974**
Base case:
Electric furnace
10.9
15.3
6.9
Wet-process phosphoric
acid plus chemical
cleanup
2,7
- 8.2
1.7
• Solvent extraction cleanup
of wet-process phosphoric
acid
8.6
- 2.3
5.4
**
Based on production in 1989 being 0.63 x 10 ton of P 0 greater than in 1974.
%
Estimated 1974 particulate emissions (based on the emission factor of 10.9 Ib/ton of P9°,-)
- 10.9 x 1.4 x 10 = 15.3 x 10b Ib/yr. L ^
-------
Other alternative processes considered, but from which emission
data are not available from the industry reports, include byproduct
sulfuric acid, strong phosphoric acid process, and secondary options.
COPPER INDUSTRY
Base Case Process - Conventional Copper Smelting
The conventional copper-recovery process involves smelting of
sulfide concentrates in a reverberatory furnace, either directly or
after roasting. The mixture of molten sulfides from the furnace is
converted to blister copper in converters. (A detailed description of
this process is given in Volume XIV, page 23.)
There are three sources of particulate emissions: roasters,
reverberatory furnaces, and converters. The particulate loading of
the waste gases depends on the characteristics of the copper concentrates
and the volume of exhaust gas. Particulate emissions from the furnaces
are predominantly metallic fumes of submicron size. The fumes are dif-
ficult to wet and readily agglomerate. In addition, they are cohesive
and will bridge and arch in hoppers and other collection bins. The
following emissions represent typical values.
The emission factor reported for roasters is 45 Ib of particulate/
ton of copper (AP-42). In addition to particulates, roaster gas contains
S0~ which is recovered in an acid plant. The acid plant requires parti-
culate-free gas, so particulate removal devices with high efficiency
are part of the control system. Collection efficiencies up to 99.7%
for particulates are attained by careful conditioning of flue gas
(Midwest Research Institute, 1971). The control equipment used is the
electrostatic precipitator alone or in combination with a pre-cleaner.
The estimated controlled emissions are 0.14 Ib/ton of copper.
The emission factor reported for a reverberatory furnace is 20 Ib/tc
of copper. The furnace emits a large volume of gas (82,000 scfm from a
copper smelter having an annual capacity of 100,000 ton/yr) having 1-2%
SO-. The SO cannot be economically recovered from the gas (Volume XIV,
page 27). Particulate control efficiency has been reported to be 99.7%
(Midwest Research Institute, 1971). Electrostatic precipitators preceded
by mechanical collectors are used as control equipment. The estimated
controlled emissions from the reverberatory furnace are 0.06 Ib/ton
of copper.
The emission factor reported for a converter is 60 Ib/ton of copper
(Midwest Research Institute, 1971). Since the majority of the particles
are large, about 75 to 85% of the solids settle in the flue system. The
particulates are further removed in high-efficiency electrostatic pre-
cipitators. The SO in the cleaned gas is recovered in the acid plant
downstream of the precipitator. The estimated controlled emissions
from the converter amount to 0.18 Ib/ton of copper.
77
-------
Electrostatic precipitators, preceded by mechanical collectors,
are usually applied to the control of particulates from roasters, rever-
beratory furnaces, and converters. The equipment is usually more massive
and rugged than its counterpart in other industries, such as utilities.
Total uncontrolled emissions from the above three sources in the
base case process are about 125 Ib/ton of copper and estimated controlled
emissions are 0.38 Ib/ton of copper.
The electricity consumption in the base case process ranges from
347 to 441 kWh/ton of copper (Volume XIV, page 37). Estimated emissions
from steam generators are 34 Ib/ton of copper with no control, and
0.42 Ib/ton of copper with control to meet the NSPS.
Process Option 1 - Outokumpu Flash-Smelting Process—
The flash-smelting alternative combines the separate roasting
and smelting operations of conventional copper extraction into one
combined roasting/smelting operation. The major advantages of the
method are a reduction in fuel used for smelting and production of a
gas stream having a concentration of SO which is suitable for sulfuric
acid manufacture. A detailed description of the process is given in
Volume XIV, page 41.
The emission sources in this process include: rotary kiln, con-
centrator, and converter. The particulate characteristics are expected
to be the same as those for the particulates in the base case process.
A direct oil-fired rotary kiln is used to dry the charge thoroughly
before it is fed to the concentrate burner. The particles leave the
kiln as flue dust and are collected in an electrostatic precipitator
and returned to the main concentrate flow. The uncontrolled or the
controlled emission factor for this source is not reported; therefore,
emissions from the rotary kiln are estimated based on the reported
emission factors of kilns in other industries. Rotary kilns used in
the cement- and lime-manufacturing industries generate particulate emis-
sions in the range of 200 to 250 Ib/ton of product (EPA, 1975). It is
estimated that uncontrolled emissions from a rotary kiln used to dry
the charge may be about 250 Ib/ton of copper. If the emissions are
controlled in an electrostatic precipitator with 99% collection efficiency,
the uncontrolled emissions are estimated at 2.5 Ib/ton of product.
The concentrator represents another source of particulate emissions,
but emission data from this source are again not available so the uncon-
trolled emission factor cannot be estimated. The gas is cleaned in
electrostatic precipitators before SO™ removal. Assuming the concen-
tration of particulates in the gas stream downstream of the precipitator
is the same as that in the base case, the estimated controlled emissions
from the concentrator would be 0.41 Ib/ton of copper. The above assumption
is based on the fact that gases in both processes have to be purified
to meet the requirements for the acid plant.
78
-------
The emissions from the converter in the flash-smelting alternative
would be comparable to or less than the emissions from the converter
in the base case process because the gas volume may be reduced due to
the high-grade matte (Volume XIV, page 43). Emissions from the converter
are estimated at 60 Ib/ton of copper with no control, and 0.18 Ib/ton
of copper with 99.7% control.
Total controlled emissions from this alternative are about 3.1 Ib/ton
of copper. Uncontrolled emissions cannot be estimated, because data are
not available. The control technology used in this alternative is the
same as that in the base case process.
The electricity consumption in this process alternative is 366 kWh/ton
of copper (Volume XIV, page 52). Estimated uncontrolled emissions from
power boilers are 30.7 Ib/ton of copper with no control, and 0.38 Ib/ton
of copper with control to meet the NSPS.
Process Option 2 - Noranda Process—
The Noranda process combines the three operations of roasting,
smelting, and converting of copper concentrates in a single reactor.
The heat losses suffered during the transfer of concentrate from the
roaster to the reverberatory furnace are suppressed, as are those
occurring during the transfer of the matte from the reverberatory
furnace to the converter. A detailed description of the process is
given in Volume XIV, page 55.
Data on the particulate emissions from the Noranda process are
not available; however, the major emission source is the Noranda reactor.
The particulate characteristics are expected to be the same as those for
the particulates in the base case process. The gas flow rate from the
Noranda reactor is estimated at 55,000 scfm from a plant having a capa-
city of 100,000 tons of copper/yr. The gas from this reactor is treated
in an electrostatic precipitator for particulate removal and the clean
gas is sent to an acid plant. Controlled emissions — assuming that the
concentration of particulates in the gas entering the acid plant is the
same as that in the base case process — amount to about 0.41 Ib/ton of
copper.
The electricity consumption in this process alternative is the same
as in the Outokumpu flash-smelting alternative, so the estimated emissions
from the steam generator are 30.7 Ib/ton of copper with no control, and
0.38 Ib/ton of copper with control to meet the NSPS.
79
-------
Process Option 3 - Mitsubishi Process—
The Mitsubishi process consists of three metallurgical stages, each
of which is carried out in a separate furnace. Thus, there is a smelting
furnace for concentrates, a converting furnace to oxidize iron in the
matte and make blister copper, and a slag-cleaning furnace. Intermediate
products in the molten state move continuously among the respective
furnaces, which are thus functionally connected with each other. A
detailed description of the Mitsubishi process is given in Volume XIV,
page 71.
All of the three furnaces represent particulate emission sources.
Again, uncontrolled emissions cannot be estimated because data are not
available; however, particulate characteristics are expected to be the
same as those for the particles in the base case process. The estimated
controlled emissions would be 0.41 Ib/ton of copper, based on the assump-
tion that the concentration of particulates in the flue gas entering the
acid plant is the same as that in the base case process.
The electricity consumption in this alternative is 366 kWh/ton of
copper (volume XIV, page 81). Estimated uncontrolled emissions from
the steam generator are 30.7 Ib/ton of copper with no control, and 0.38
Ib/ton of copper with control to meet the NSPS.
Process Option 4 - The Use of Oxygen in Smelting—
Copper smelting can be conducted with pure oxygen or by using oxygen-
enriched air. A detailed description is given in Volume XIV, page 82.
The specific example selected for examination is Outokumpu flash smelting.
The particulate emissions from this alternative cannot be estimated, because
no data are available. Oxygen enrichment results in the reduction of
effluent volume, but operating temperatures are generally increased.
Therefore, the emissions would be lower because of the low gas volume,
but the effect of temperature is not known; so the change in emissions
cannot be predicted. If the gas is cleaned to the same particulate con-
centration as that in the base case process, the controlled emissions
in this alternative will be lower than those in the base case process
because the gas flow rate is lower.
80
-------
Process Option 5 - Metal Recovery from Slag—
In conventional copper smelting, converter slag is recycled to
the reverberatory furnace and all the slag tapped from the furnace is
discarded. The copper contained in the discarded slag is lost. The
amount of copper lost is significant; about 1.5 to 3.0% or more of the
copper in the feed materials. Two processes for recovering metal from
slag '- flotation and the electric furnace — are described in Volume
XIV, page 85.
In the flocculation process, cooling, crushing, and grinding
represent the particulate emission sources. In the electric furnace
process, the furnace itself is the emission source, but the volume of
gas is small. The emissions from these sources cannot be quantified,
because no data are available.
Process Option 6 - The Arbiter Process —
The Arbiter process is a hydrometallurgical process. A process
description is given in Volume XIV, page 95. Particulate emissions
from this alternative cannot be quantified, because no data are available,
but the process itself causes little air pollution. The process is
energy-intensive and uses large quantities of electricity and steam.
As reported (Volume XIV, page 104), steam consumption is 20,000 Ib/ton
of copper and electricity consumption is 3,0-0 kWh/ton of copper.
The estimated particulate emissions from the steam generator are 410 Ib/ton
of copper with no control, and 5.2 Ib/ton of copper with control to meet
the NSPS. Thus, the Arbiter process, in addition to not having the
anticipated energy benefits, also has rather significant environmental
problems.
gummary
The particulate emission factors for the copper industry are sum-
marized in Table 22. The uncontrolled emission factors in most of the
pyrometallurgical processes cannot be estimated, but may be of the same
order as those for the base case process, except for the Outokumpu flash-
smelter alternative where a kiln is part of the process and may generate
significantly more particulates.
The uncontrolled emissions from the hydrometallurgical process
(Arbiter) are significantly lower than those from the pyrometallurgical
processes because of the nature of the hydrometallurgical process;
however, the total emissions, including those from the steam generators,
are significantly higher for the hydrometallurgical process because of
the consumption of large quantities of steam and electricity.
81
-------
TABLE 22. ESTIMATED PARTICIPATE EMISSION FACTORS - PRIMARY COPPER INDUSTRY
Process
Base case:
Conventional smelting
• Outokumpu flash smelting
• Noranda
• Mitsubishi
• Arbiter
Emission
factor
- no control
(Ib/ton of copper)
Process Power boiler
125
N.A.
N.A.
N.A.
low
34
30.
30,
30.
410
7
7
7
Total
159.0
N.A.
N.A.
N.A,
410.0
Emission
factor
- with
control
(Ib/ton of copper)
Process Power boiler Total
0.
3.
0.
0.
38
1
41
41
low
0
0
0
0
5
.42
.38
.38
.38
.2
0.
3.
0.
0.
5.
80
5
79
79
2
Control
efficiency
99.5
—
—
—
98.7
oo
N5
-------
TABLE 23. ESTIMATED PARTICIPATE EMISSIONS - COPPER SMELTING
CO
U)
Process
Base case:
Conventional smelting
• Outokumpu flash smelting
• Nornada
• Mitsubishi
• Arbiter
Total controlled
particulate emission factor
Change in
(Ib/ton of copper) emission factor
0.80
3,5 + 2.7
0.79 - .01
0.79 - .01
5.2 + 4.4
Particulate
emission
(10b Ib/yr)
1974** 1989-1974*
1.3 .9
3.8
.9
.9
5.7
**
Based on production in 1989 being 1.1 million tons greater than in 1974,
Estimated 1974 emissions (based on the emission factor of 0.8 Ib of particulate/ton of anode
copper)are 0.8 x 1.6 x 10 Ib/yr.
-------
Particulate emissions in the copper industry are well controlled
for the simple reason that the gas contains sulfur dioxide, and the
sulfur dioxide recovery plants require particulate-free gas. The con-
trolled emissions from most of the pyrometallurgical processes are
reduced to about 0.4 Ib/ton of copper.
The controlled emission factors for the base case process and
alternative processes are comparable, except for the Outokumpu flash-
smelter and Arbiter process alternatives. In the Outokumpu flash-smelter
alternative, emissions are higher, because a kiln which produces large
emissions is part of the process; in the Arbiter process, alternative
emissions are also higher because of the large consumption of electricity
and steam.
Emissions from the copper industry are summarized in Table 23.
As seen here, the controlled emissions from the alternative processes
are comparable to those in the base case process or higher. The total
particulate emissions are estimated at 1.3 x 10 Ib/yr, based on the
production rate of 1.6 x 10 tons of copper/yr in 1974; and are expected
to increase to about 2,2 x 10 Ib/yr in 1989, based on the estimated
production of 2.7 x 10 tons/yr. However, if the Outokumpu flash
smelting process, or the Arbiter process, is installed over the incre-
mental capacity from 1974,to 1989, the total particulate emissions in 1989
will increase to 5.1 x 10 Ib/yr or 7.0 x 10 Ib/yr, respectively,
significantly higher than those with the base case process.
AMMONIA INDUSTRY
In the remaining industry sectors, particulate emissions from the
processes were not considered to be of major importance in the original
13 industry study. However, in many cases, there may be significant
differences in electric power or steam requirements which could affect
emissions at the power boiler. These remaining industry sectors are
discussed in the following text.
The base case technology is the production of ammonia based on
steam reforming and using natural gas as the feedstock. In the alter-
native processes, ammonia is produced via coal and heavy oil feedstocks.
Estimated particulate emissions are summarized in Table 24 with details
presented in the following discussion.
Base Case Process - Ammonia Production Based on Gas Feedstock
The four major operations in the manufacture of ammonia include:
gas preparation, hydrogen production, gas purification, and ammonia
84
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TABLE 24. ESTIMATED CONTROLLED PARTICULATE EMISSIONS - AMMONIA INDUSTRY
Process
Particulate emission factor for ammonia production
(Ib/ton of ammonia) Change in
Process Power boiler Total emission factor
Particulate
emission
(10b Ib/yr)
1974** 1989-1974*
Base case:
Natural gas
• Coal gasification
• Heavy fuel oil
0.21
0.52
0.08
f
0.05
0.17
0.11
0,26
0.69
0,19
t
+ 0.43
- 0.07
2.4
3.3
8.8
2.4
t
* 6
Based on production in 1989 being 12.8 x 10 tons greater than in 1974.
**
Estimated 1974 emissions, based on the total emission factor of 0.26 Ib of particulate/ton of
ammonia, are 0.26 x 9.2 x 10 = 2,4 x 10 Ib/year.
Coal dust emissions from receiving, handling, and grinding operations are not included in this
emission factor.
-------
synthesis. Gas is typically prepared by steam reforming of desulfurized
natural gas to produce carbon monoxide and water. In the second step,
the project gases are normally catalytically shifted to carbon dioxide
and hydrogen. The carbon oxides are reacted with water to form more
hydrogen. Ammonia is then synthesized by the reaction between hydrogen
and nitrogen (produced from atmospheric air) at elevated temperatures
and pressures in the presence of a catalyst. A detailed description
of the base case technology is presented in Volume VII, page 25,
Process energy requirements include natural gas (12.6 x 10 Btu/ton)
which is used to fire the steam reformer. Steam is generated by heat
recovered from the flue gas leaving the primary reformer and from the
process gases leaving the secondary reformer. Additional steam is
generated from auxiliary gas-fired boilers only during startup. Power
requirements are estimated at 45.5 kWh/ton of ammonia.
Particulate emissions from the natural gas-fired reformer — based
ie emissions factor of O.I
to be 0.21 Ib/ton of ammonia.
on the emissions factor of 0.017 lb/10 Btu (EPA, 1975) — are estimated
Particulate emissions from the power boiler are estimated to be
3.82 Ib/ton if the emissions are uncontrolled, and 0.05 Ib/ton of ammonia
is emissions are controlled to meet the NSPS.
Process Option 1 - Ammonia Production Based on Coal Gasification
Synthesis gas for ammonia production is obtained from the coal
feedstock by freeing the hydrogen that is present in the coal and by
reacting the carbon in the coal with steam to produce additional hydrogen
and carbon monoxide. As in the base case process, the synthesis gas is
shifted to a hydrogen and carbon dioxide product, the gases are purified,
and ammonia is synthesized from nitrogen to the hydrogen product. The
details of this process option are described in Volume VII, page 37.
An auxiliary coal-fired boiler is required for this process alter-
native. Coal requirements are estimated at 5.22 x 10 Btu/ton of ammonia.
In addition, electrical power requirements have been estimated to be
1.70 x 10 Btu/ton.
Particulate emissions from the process heat requirements are
estimated at 0.52 Ib/ton of ammonia, if emissions are controlled to meet
the NSPS, and 41.76 Ib/ton of ammonia, if emissions are uncontrolled.
Particulate emissions from the coal unloading, handling, and grinding
operations have not been estimated.
Particulate emissions from the power requirements are estimated
at 13.61 Ib/ton if emissions are uncontrolled, and 0.17 Ib/ton if
emissions are controlled to meet the NSPS.
86
-------
Process Option 2 - Production of Ammonia from Heavy Fuel Oil-—
The production of ammonia from heavy fuel oil involves producing
synthesis gas from fuel oil by the partial oxidation and steam reforming
of the hydrocarbons. The carbon monoxide and steam in the product gases
are subsequently reacted catalytically to produce additional hydrogen.
The acid gases, carbon oxides, and other impurities are removed from
the hydrogen stream. Ammonia is finally synthesized from the hydrogen
and nitrogen. An air separation plant supplies nitrogen for the
synthesis and oxygen for the partial oxidation of the fuel oil. This
process option is described further in Volume VII, page 67.
Process fuel requirements were estimated to include fuel oil and
naphtha at approximately 7.26 x 10 Btu/ton of ammonia. Power require-
ments are estimated at 103 kWh/ton.
Controlled particulate emissions from process fuel, based on an
emissions factor of 0.011 lb/10 Btu (Volume VII, page 71, 76) are
estimated to be 0.08 Ib/ton.
Particulate emissions from the power boiler are estimated to be
8.65 Ib/ton if emissions are uncontrolled, and 0.11 Ib/ton of ammonia
if emissions are controlled to meet the NSP3.
CHLOR-ALKALI INDUSTRY
Chlorine and Cuastic Production
Base Case Process - Graphite Anode Diaphragm Cell—
The graphite anode diaphragm cell was selected as a basis for
judging the energy and environmental effects resulting from the process
changes studied, i.e., conversion to both modified annodes and diaphragms,
both changes being aimed at energy conservation.
Chlorine and caustic soda are produced by the electrolysis of
brine. In the Diaphragm cell, chlorine is formed at the graphite anode,
while sodium ions migrate through the cell diaphragm to the cathode
where a dilute solution of NaOH is produced. A more detailed description
of this process is presented in Volume XII, page 21-25.
The electrolysis of brine is an energy-intensive process requiring
about 3,274 kWh/ton of chlorine. In addition, the plant requires 7,368 lb
of low-pressure steam/ton of chlorine for caustic evaporation and brine
heating.
Particulate emissions from power generation are estimated at 3.44 Ib/ton
of chlorine if the NSPS for coal-fired units is met. Without particulate
removal, emissions are estimated at 275 Ib/ton of chlorine. It was
assumed (Volume XII, page 26) that the steam would be generated with
87
-------
byproduct hydrogen supplemented with natural gas. Uncontrolled particulate
emissions from steam generation, based on the emissions factor 0.017
lb/10 Btu (AP-42), are estimated to be 0.16 Ib/ton of chlorine.
Process Option 1 - Dimensionally Stable Anode—
The dimensionally stable anode (DSA), constructed of titanium and
coated with precious metal/rare earth oxides, offers power savings of
up to 20% over the graphite anode. Moreover, the anode area and anode-
cathode spacing of the DSA remain constant throughout use, thereby
preventing increased voltage requirements over time. Additional
characteristics of the DSA are presented in Volume XII, page 44-47.
The DSA diaphragm cell process requires 3,151 kWh and 6,402 Ib of
steam/ton of chlorine. Steam is generated by the byproduct hydrogen
and natural gas. Uncontrolled particulate emissions from steam generation
are estimated to be 0.14 Ib/ton of chlorine. Particulate emissions from
power generation are estimated at 3.31 Ib/ton of chlorine, if the NSPS
for coal-fired units is met, and 265 Ib/ton of chlorine if the emissions
are uncontrolled.
Process Option 2 - Expandable DSA—
Cell power consumption can be reduced by decreasing the gap between
the anode and the cathode. With the rigid DSA, a "working" space must
be allowed in which to assemble the cell. The expanded DSA is con-
structed so that the electrodes can be moved inward after the cell is
assembled. This reduced spacing results in a reduction of about 325
kWh/ton of chlorine compared to the rigid DSA configuration. If emissions
are controlled to meet the NSPS, then this power savings reduces parti-
culate emissions from the power boiler by about 0.35 Ib/ton of chlorine
from the particulate emissions estimated for the rigid DSA cells. If
emissions are uncontrolled, then this power savings reduces particulate
emissions by 27.3 Ib/ton of chlorine.
Process Option 3 - Polymer-Modified Asbestos—
By replacing the conventional asbestos diaphragm by one which is
polymer-treated and baked into place on the cathode, power consumption
can be reduced because diaphragm swelling does not occur. Electrical
consumption may be reduced by as much as 280 kWh/ton if an extra wide
anode is used. Thus, particulate emissions controlled to meet the NSPS
are estimated to be 0.29 Ib/ton of chlorine less than the emissions esti-
mated for the rigid DSA cells with standard diaphragms. Without parti-
culate removal, particulate emissions would be about 23.5 Ib/ton of
chlorine less.
88
-------
Process Option 4 - Polymer Membranes—
Microporous teflon-type polymer membranes which would replace
the asbestos diaphragm entirely are being developed. These would give
an energy performance equivalent to the polymer-modified asbestos with
the "extra-wide" anode. Hence, the controlled and uncontrolled emissions
would be identical to those of process option 3.
Process Option 5 - Ion Exchange Membranes—-
These membranes would separate the anode and cathode compartments
of the cell and would allow the diffusion of sodium ions to the cathode
but would not allow the diffusion of hydroxyl ions to the anode. Thus,
the ion exchange cell would be capable of producing a 25 to 40% caustic
solution, whereas the standard cell produces a 10% caustic solution.
Energy use for a DSA with an ion exchange cell producing 40% NaOH
is 2,980 kWh and 1,466 Ib of steam/ton of chlorine. Significantly
less steam is required since a rather concentrated NaOH solution is
produced directly from the cell. Controlled particulate emissions
from steam generation by natural gas and byproduct hydrogen are
estimated at 0.03 Ib/ton of chlorine. Particulate emissions from power
generation is estimated to be 3.13 Ib/ton of chlorine if the NSPS for
coal-fired boilers is met. Without particulate control, emissions would
be 250 Ib/ton of chlorine.
Process Option 6 - Mercury Cells—
Chlorine and caustic may also be produced in a mercury cell in
which brine flows through a slightly sloped trough. Chlorine is produced
at the dimensionally stable anodes, located at the top of the trough.
A dilute sodium amalgam is produced at the cathode (a thin layer of
mercury which flows along the bottom of the trough), a 50% caustic
solution is produced from the amalgam, with the mercury recycled to the
cell. Energy requirements for the mercury cell include 3,712 kWh of
power and 550 Ib of steam/ton of chlorine.
Uncontrolled particulate emissions from steam generation by
natural gas and byproduct hydrogen are estimated to be 0.02 Ib/ton of
chlorine. Particulate emissions produced by power generation are esti-
mated at 3.89 Ib/ton of chlorine if the NSPS for coal-fired boilers is
met. Without particulate control, emissions would be about 312 Ib/ton
of chlorine.
Summary
The emissions factor and total emissions for the base case and
alternative processes are presented in Table 25. The modified anodes
and modified diaphragm options offer a 4 to 14% annual reduction in
particulate emissions from the base case process.
89
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TABLE 25. ESTIMATED PARTICIPATE EMISSIONS - CHLOR-ALKALI INDUSTRY
Particulate emission factor
Process
Base case:
Graphite-anode
diaphragm cell**
• Dimensionally stable
anodes
• Expandable DSA
• Polymer-modified
asbestos
• Polymer membrane
• Ion exchange membrane
• Mercury cell
(Ib/ton of chlorine)
Process Power boiler Total
0.16
0.14
0.14
0.14
0.14
0.03
0.02
3.44 3,60
3.31 3.45
2,97 3.11
3.02 3.16
3.02 3.16
3.13 3.16
3.89 3.91
Change in
emission factor
-
- 0.15
- 0.49
- 0.44
- 0.44
- 0.44
+ 0.31
Particulate
emission
(10 lb/yr)
1974** 1989-1974*
39.6 42.8
41.1
37.0
37.6
37.6
37.6
46.5
* 6
Based on production in 1989 being 11.9 x 10 tons greater than in 1974.
**
Estimated 1974 emissions, based on the total emission factor of 3,60 Ib of particulate/ton of
chlorine, are 3.6 x 11.0 x 10 = 39.6 x 10 Ib.
Emissions controlled to meet the NSPS for coal-fired boilers.
-------
The mercury cell, however, is estimated to result in a 9% annual
increase in particulate emissions compared to the base case, because
of the relatively larger power requirements.
FERTILIZER INDUSTRY
Nitric Acid Production
The manufacture of nitric acid, described in Volume XV, page 25-28,
generates significant emissions of nitrogen oxide. Adoption of air
pollution control is a recent practice in the industry. The process
change considered in the nitric acid production is the application of
alternative NO abatement systems. These processes are described in
Volume XV, page 33-42.
Base Case Process - Nitric Acid Production without NO Emission Control—
x
Nitric acid is produced by the oxidation of ammonia, usually under
high pressure and temperature, over a platinum catalyst. Waste heat
recovered from the product gases is used to generate steam. The cooled
gases are subsequently sent to an absorption tower to form the acid
product.
Process heating requirements are satisfied by natural gas. Steam
generated by the waste heat is included as an energy credit. An analogous
credit for particulate emissions was assumed since the steam generated
by the waste heat would otherwise be generated by low-sulfur residual
fuel oil. The particulate emissions credit, based on the emission factor
of 3 lb/1,000 gal of oil burned, is estimated to be 0.01 Ib/ton of acid.
Process Option 1 - Catalytic Reduction—
In the catalytic reduction process, tail gas from the absorber
passes through a combustor where the nitrogen oxides are reduced to N
and 0_. Natural gas is used as a fuel in the combustor. Steam is
generated by waste heat recovered from the product gases.
Energy requirements for the process include natural gas and
electricity. Although catalytic reduction is an energy-intensive process,
there is a particulate emissions credit because steam, which would other-
wise be generated by oil, is generated with waste heat from the process.
The net particulate emissions credit is estimated to be 0.01 Ib of
particulate/ton of nitric acid.
Process Option 2 - Molecular Sieve Method—
This method is based on the principles of absorption, oxidation,
and regeneration of the molecular sieve. An oil-fired heater is used
to provide heat for regeneration of the sieve. The process has high
efficiency for removal of NO gases. A detailed description of the
method is given in Volume XV, page 36.
91
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Energy requirements include fuel oil, steam, and electricity. High
power requirements (26 kWh/ton of acid) result from the added compression
requirements and the need to regenerate the sieve. Particulate emissions
from power boilers without control are estimated to be 2.17 Ib/ton of
acid, and 0.03 Ib/ton of acid from power boilers with particulate control
required to meet the NSPS. Controlled particulate emissions from the
low-sulfur residual fuel oil used in the sieve regeneration and steam
production are estimated at 0.4 Ib/ton of acid.
Process Option 3 - Grand Paroisse or Extended Water Absorption—
In this process, tail gas form the existing absorption tower is
delivered to a second absorption tower for "extended absorption nitrogen
oxides by water."
The energy requirements for this process are small — only 7.2 Kwh
are used per ton of nitric acid product. Power plant emissions are
estimated at 0.60 Ib/ton of acid if the NSPS for coal-fired units is
met, and 0.01 Ib/ton of acid for plants without particulate control.
CDL/Vitak Process—
In the CDL/Vitak process, the tail gas is scrubbed with nitric acid
under conditions which reduce the nitrogen oxides to the desired level.
Energy requirements for this process include steam and electricity. The
total steam requirements will result in particulate emissions of 1.14
Ib/ton of acid if low-sulfur residual fuel oil is burned. Electrical
requirements (22 kWh/ton of acid) will result in particulate emissions
of 0.02 Ib/ton of acid if the flue gas is cleaned to meet the NSPS
for coal-fired boilers and 1.81 Ib/ton if emissions are uncontrolled.
Masar Process—
In the Masar process, the tail gas is chilled and then scrubbed
with an urea-containing solution. As nitric acid is produced, the urea
hydrolyzes and forms ammonium nitrate. Steam (consumed at 105,000 Ib/ton
of acid) and electricity (consumed at 1.5 kWh/ton of acid) are required
for this process. Steam generation by low-sulfur residual fuel oil will
result in 2.10 Ib of particulate/ton of acid. Electricity generation
contributes 0.13 Ib/ton of acid if emissions are uncontrolled, and a
negligible amount of particulate if the emissions are controlled to
meet the NSPS.
Conversion to Fuel Oil in Mixed Fertilizer Plants Equipped with Bag Filters
Base Case Process—
The base case operation is an ammoniation granulation plant which
uses a natural gas-fired dryer and is equipped with a bag house filter
to control fertilizer dust produced during drying. Only 20% of the
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estimated 200 plants are equipped with bag houses and would therefore be
affected by this process change. Uncontrolled emissions from a granulation
plant are estimated at 2.91 Ib/ton of fertilizer; uncontrolled emissions
from the dryer and cooler are estimated at 0.46 Ib/ton of fertilizer
(Volume XV, page 49). Bag houses operating at 99.8% removal efficiency
would reduce the emmisions from the dryer to less than 0.01 Ib/ton of
fertilizer. Power requirements for the bag house are estimated to be
1.7 kWh/ton. Particulate emissions are estimated to be 0.15 Ib/ton from
uncontrolled sources and are negligible from power boilers which meet
the NSPS.
Installation of Scrubber on Bag House-Equipped Plants When Converting
from Natural Gas to Fuel Oil—
When fertilizer dryers were converted from natural gas to oil,
operational problems sometimes resulted when the bag house filters
became plugged with ash from the oil. If these problems cannot be
resolved by the modification of the combustion process, then wet scrubbers
will be required for particulate control.
Incremental particulate emissions resulting from conversion to low-
sulfur residual fuel oil may be considered negligible, since the fly
ash would be removed in the scrubber. The lower removal efficiency of
the scrubber as compared to the bag house is not sufficiently different
to have an impact on the emission factor.
Power requirements for the scrubber operation are estimated to be
three times greater than those for bag house operation, Particulate
emissions from the power boiler are estimated to be 0.01 Ib/ton of
fertilizer if emissions are controlled to meet the NSPS, and 0.45 Ib/ton
of fertilizer if emissions are uncontrolled.
Continued Operation of the Bag House Filter after Conversion from
National Gas to Fuel Oil—
If filter clogging problems can be alleviated by proper design and
operation of the oil-fired dryer, the bag houses will not have to be
replaced by scrubbers. Incremental particulate emissions resulting from
the fuel conversion would be negligible since the fly ash would be
removed in the bag house. Power requirements and emission factors for
the bag house would be about the same as the base case process.
Summary
The emission factors and total emissions for the base case and
alternative processes for NO abatement and fuel conversion in fertilizer
drying are presented in Table 26. For NO abatement in nitric acid
production, only the catalytic reduction process option offers a reduction
of particulate emissions from the base case process. This is primarily a
result of the large power requirements for the NO control systems.
X
93
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TABLE 26. ESTIMATED CONTROLLED PARTICULATE EMISSIONS - FERTILIZER INDUSTRY
Particulate emission factor
Process
(Ib/ton of nitric
Process Power boiler
Nitric acid production - control of NO emissions by
X
Base case:
No NO control**
X
• Catalytic reduction
• Molecular sieve
• Grand Paroisse
• CDL/Bitak
• Masar
Converting fertilizer dryers
Base case:
Natural gas
• Better equipment
techniquet
• Installing scrubbers
- 0.01 0.0
- 0.02 0.01
0.4 0.03
0.0 0.01
1.14 0.02
2.10 < 0,0
(with bag houses) from
< 0.01 nil
< 0.01 0.0
< 0.01 0.01
acid)
Total
various
- 0.01
- 0,01
0.43
0.01
1.16
2.10
natural
< 0.01
< 0.01
< 0.02
Change in
emission factor
technologies.
0.0
.44
0.02
1.17
2.11
gas to oil.
-f
0.0
0.01
Particulate
emission
(10b Ib/yr)
1974** 1989-1974*
- 0.08 - 0.7
- 0.7
2.9
0,07
7.7
13.9
O.llf < 0.08ft
< 0.08+t
< 0.16ft
* 6
Based on nitric acid production in 1989 being 6.6 x 10 tons greater than in 1974.
**
Estimated 1974 emissions based on total emission factor (credit) of -0.01 Ib/ton of acid are
-0.01 x 8.2 x 10 = 0.08 x 10 ton/yr (particulate emissions credit since energy is recovered
in this process).
(continued)
-------
TABLE 26. (continued)
Estimated 1974 emissions based on total emissions factor of 0.01 Ib/ton of fertilizer are 0.01 x 10.0 x
10 = 0.10 ton/yr.
j.j. £
Calculated using a 4% growth rate for 15 years based on,10 x 10 tons/yr in 1974 and rising to
18 x 10 tons in 1989; this potential growth of 8 x 10 tons is multiplied by the emission factor.
-------
Fuel conversion for fertilizer dryers equipped with bag house filters
has a small impact on the total amount of particulate emissions on an
industry-wide basis since only 20% of the fertilizer plants are equipped
with these air filters.
TEXTILES INDUSTRY
Two textile mills — an integrated knitting mill and an integrated
weaving mill — were examined. The mill operation includes the knitting
of greige yarn or the weaving of greige fabric and subsequently dyeing
and finishing the fabric.
Knit Fabrics Production
Base Case Process—
In the knitting mills, yarn is knitted into fabric in the greige
mill. The greige fabric is next scoured to remove knitting oil, and
then dyed, washed, and spun-dry to remove as much water as possible
before hot-air drying. A finish (softener/lubricant) is then applied
to the fabric, which is dried and heat-set. Details of the knitting
mill operation are presented in Volume IX, page 33.
Natural gas is used for the hot-air drying and heat-set operations.
Particulate emissions include merely a small amount of lint. The quantity
of this lint is not estimated in Volume IX. It is unlikely that the
natural gas will be supplemented as it is required by all of the equip-
ment presently available for fabric drying and heat-setting operations.
Steam is used for the heat input to the scouring, dyeing, and washing
operations. In the base case process, it was assumed that the steam
would be generated with low-sulfur residual fuel oil. Estimated
emissions — based on the emission factor of 3 lb/1,000 gal of oil burned
in the boiler — are 0.16 Ib/ton of fabric. Because of the relatively
small energy requirements of textile mills, it seems unlikely that coal
will be used as a fuel for steam production (Volume IX, page 41).
Electricity is required to provide mechanical energy to transfer fabric
from the beginning to the end of the process line and for knitting the
yarn into the fabric. Electrical requirements of 360 kWh/ton of fabric
will result in particulate emissions of about 0.38 Ib of particulate/ton
of fabric if the NSPS is met. Without particulate control, emissions
will be 30.2 Ib/ton of fabric.
Advanced Aqueous Processing—
In advanced aequeous processing, the sequence of operation is
similar to that of the base case, except that the hot air drier is
replaced by an air/vacuum extractor, thereby reducing natural gas
requirements and increasing electrical requirements. Secondly, the
scouring, dyeing, and washing operations are modernized with more
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efficient equipment, thereby reducing steam requirements. Advanced
aqueous processing is described in detail in Volume IX, page 535-537.
Natural gas is used for the heat-setting operation; hence, there
are no fuel-related particulate emissions. However, some lint is emitted,
although this amount was not estimated in the Textile Industry Report
(Volume XI).
Steam requirements of 3,800 Ib/ton of fabric will result in
0.08 Ib of particulate/ton of fabric if the steam is generated by fuel
oil so that flue gas desulfurization is not required. Electrical require-
ments of 500 kWh/ton of fabric will result in 0.53 Ib of particulate/ton
of fabric if the NSPS is met. Without particulate removal, emissions
would be 42.0 Ib of particulate/ton of fabric.
Solvent Case—
Solvent systems are assumed for the scouring, dyeing, and finishing
operations. The fabric is steam-stripped to remove residual solvent.
Clean solvent is recovered by distillation with steam. Details of this
solvent system are provided in Volume IX, page 37-41.
Natural gas is used for the heat-setting operation; hence there are
no fuel-related particulate emissions. However, some lint is emitted,
although this amount was not estimated in the Textile Industry Report
(Volume IX). Steam requirements of 2,200 Ib/ton of fabric will result
in 0.04 Ib of particulate/ton of fabric. Electricity requirements
of 240 kWh/ton of fabric will result in 0.25 Ib of particulate/ton of
fabric if the NSPS is met. Without particulate control, emissions would
be about 20.2 Ib of particulate/ton of fabric.
Woven Fabrics Production
Base Case Process—
The operations of woven fabric preparation, dyeing, and finishing
involve a much longer processing sequence than knit fabrics. These steps
are described in Volume IX, page 44. Natural gas is used in the drying,
setting, and curing operations; hence, there are not fuel-derived parti-
culate emissions in these steps. However, some lint may be emitted,
although the quantity was not reported in Volume IX.
Steam (15 Ib/ton of fabric) is used for process water heating in
the dyeing, washing, and finishing steps. Steam generation will result
in 0.6 Ib of particulate/ton of fabric if low-sulfur residual oil is
burned. Electrical energy requirements are estimated at 580 kWh/ton
of product. This will result in particulate emissions of 0.61 Ib/ton
of fabric if the NSPS is met. Otherwise, uncontrolled emissions are
estimated at 48.7 Ib/ton of fabric.
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Advanced Process—
The advanced processing includes a polyvinyl alcohol (PVA) recovery
loop in which concentrated PVA solution is recycled back to sizing and
the hot water back to the desizing operation. Details of the advanced
case sequence are presented in Volume IX, page 49.
Natural gas is used in the drying, setting, and curing operations;
hence, there are no fuel-derived particulate emissions in these steps.
However, some lint may be emitted, although the quantity was not
reported in Volume IX.
Steam requirements have been reduced to 6.4 Ib/ton of fabric by
reduction in overall process water use and recycling of wash waters.
This steam generation will produce 0.25 Ib of particulate/ton of fabric
if these emissions are not controlled. Electrical requirements have
been reduced to 300 kWh/lb of steam. This will result in particulate
emissions of 0.32 Ib/ton of fabric if the NSPS is met. Without control,
emissions are estimated at 25.2 Ib/ton of fabric.
Summary
The emissions factor and total emissions for the base case process
and alternative processes are summarized in Table 27.
The particulate emissions from the advanced process for the knitted
fabric are slightly higher than those from the base case process due to
increased power requirements. Particulate emissions from the remaining
alternatives are 50% - 53% lower than those of the corresponding base
case processes.
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TABLE 27. ESTIMATED PARTICIPATE EMISSIONS - TEXTILE INDUSTRY
Process
Knit fabric
Base case**
• Advanced case
• Solvent case
Woven fabric
Base case
• Advanced case
Particulate
(Ib/ton fabric)
Process Power boiler
0.16
0.08
0.04
0.60
0.25
.0.38
0.53
0.25
0.61
0.32
emission
Total
0.54
0.61
0.29
1.21
0.57
factor
Change in
emission factor
—
+ 0.07
- 0.25
__,_
0.64
Particulate
emission
(10 Ib/yr)
1974** 1989-1974*
0.17 0.06
0.07
0.03
2.5 0.98
0.46
* 66
Based on production in 1989 being 0.12 x 10 tons (knit fabric) and 0.81 x 10 tons (woven fabric).
**
Estimated 1974 emissions from knit fabric production based on,the total emission factor of 0.54 Ib
of particulate/ton of fabric are .54 x 0.32 x 10 = 0.17 x 10 Ib.
Estimated 1974 emissions from woven fabric production based on total emission factor of 1.21 Ib of
particulate/ton of fabric are 1.21 x 2.1 x 10 = 2.5 x 10 ton/yr.
-------
REFERENCES
Edlund, C., A.H. Lambe and J. Jeffrey, Effects of Water Quality on
Coke Quench Tower Particulate Emission, presented at the 70th Annual
APCA Meeting, Toronto, June 1977.
U.S. Environmental Protection Agency, AP-42, Compilation of Air Pollution
Emission Factors, Second Edition, March 1975.
Arthur D. Little, Inc., Steel and the Environment, report to the
American Iron and Steel Institute, May 1975.
Midwest Research Institute, Particulate Pollutant System Study,
Handbook of Emission Properties, Vol. Ill, U.S. Environmental
Protection Agency, Contract No. CPA 22-69-104, May 1971.
100
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
PE0PA-6°00/7-79-l45
1. REPORT
3. RECIPIENT'S ACCESSION-NO.
4. TITLE ANDSUBTITLE
Environmental Considerations of Selected Energy-
Conserving Manufacturing Process Options -
Volume XVIII Participates Summary Report
5. REPORT DATE
6. PERFORMING ORGANIZATION CODE
August 1979 issuing date
7. AUTHOR(S)
Arthur D. Little, Inc.
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Arthur D. Little, Inc.
20 Acorn Park
Cambridge, MA 02140
10. PROGRAM ELEMENT NO.
1NE 624B
11. CONTRACT/GRANT NO.
68-03-2198
12. SPONSORING AGENCY NAME AND ADDRESS
Industrial Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/600/12
15. SUPPLEMENTARY NOTES
T6. ABSTRACT
Under EPA Contract No. 68-03-2198, Arthur D. Little, Inc. undertook a study of
the "Environmental Considerations of Selected Energy-Conserving Manufacturing
Process Options." Some 80 industrial process options were examined in 13
industrial sectors. Results were published in 15 volumes, including a summary,
industry prioritization report, and 13 industry oriented reports (EPA-600/7-76-034
a through o).
This present report summarizes the information regarding particulates in the
13 industry reports. Four parallel reports treat sulfur oxides, nitrogen oxides,
solid residues and toxics/organics. All of these pollutant oriented reports are
intended to be closely used with the original 15 reports.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Energy, Pollution, Industrial Wastes
b.IDENTIFIERS/OPEN ENDED TERMS
Manufacturing Processes,
Energy Conservation
c. cos AT i F-ield/Group
68D
•^DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (This Report)
UNCLASSIFIED
20. SECURITY CLASS (This page)
UNCLASSIFIED
21. NO. OF PAGES
109
22. PRICE
EPA
Form 2220-1 (9-73)
101
: US GOVERNMENT PDIHTING OFFICE: 19« -657-060/5406
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