EPA-600/2-77-107J
September 1977
Environmental Protection Technology Series
SOURCE ASSESSMENT:
ACRYLONITRILE MANUFACTURE
(AIR EMISSIONS)
5S2Z
Industrial Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
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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 five series These five broad
categories were established lo facilitate further development and application of
environmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed to develop and
demonstrate instrumentation, equipment, and methodology to repair or prevent
environmental degradation from point and non-point sources of pollution This
work provides the new or improved technology required for the control and
treatment of pollution sources to meet environmental quality standards.
EPA REVIEW NOTICE
This report has been reviewed by the U.S. Environmental
Protection Agency, and approved for publication. Approval
does not signify that the contents necessarily reflect the
views and policy of the Agency, nor does mention of trade
names or commercial products constitute endorsement or
recommendation for use.
This documenl is available lo the public through the Nalional Technical Informa-
tion Service. Springfield. Virginia 22161
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EPA-600/2-77-107J
September 1977
SOURCE ASSESSMENT:
ACRYLONITRILE MANUFACTURE
(AIR EMISSIONS]
by
T. W. Hughes and D. A. Horn
Monsanto Research Corporation
1515 Nicholas Road
Dayton, Ohio 45407
Contract No. 68-02-1874
ROAP No 21AXM-071
Program Element No. 1AB015
EPA Task Officer: Irvin A. Jefcoat
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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PREFACE
The Industrial Environmental Research Laboratory (IERL) of EPA has
the responsibility for insuring that pollution control technology
is available for stationary sources to meet the requirements of
the Clean Air Act, the Federal Water Pollution Control Act, and
the solid waste legislation. If control technology is unavailable,
inadequate, uneconomical, or socially unacceptable, then financial
support is provided for the development of the needed control
techniques for industrial processes and extractive process indus-
tries. Approaches considered include: process modifications,
feedstock modifications, add-on control devices, and complete
process substitution. The scale of the control technology pro-
grams ranges from bench- to full-scale demonstration plants.
The Chemical Processes Branch of the Industrial Processes Division
of IERL has the responsibility for investing tax dollars in pro-
grams to develop control technology for a large number (>500) of
operations in the chemical industries. As in any technical pro-
gram, the first question to answer is, "Where are the unsolved
problems?" This is a determination which should not be made on
the basis of superficial information; consequently, each of the
industries is being evaluated in detail to determine if there is,
in EPA's judgment, sufficient environmental risk associated with
the process to invest in the development of control technology.
This report contains the data necessary to make that decision for
the air emissions from acrylonitrile manufacture.
Monsanto Research Corporation has contracted with EPA to investi-
gate the environmental impact of various industries which repre-
sent sources of pollution in accordance with EPA's responsibility
as outlined above. Dr. Robert C. Binning serves as Program Manager
in this overall program entitled "Source Assessment," which
includes the investigation of sources in each of four categories:
combustion, organic materials, inorganic materials, and open
sources. Dr. Dale A. Denny of the Industrial Processes Division
at Research Triangle Park serves as EPA Project Officer. In this
study of acrylonitrile manufacture, Mr. Kenneth Baker, Mr. Edward
J. Wooldridge, and Dr. I. Atly Jefcoat served as EPA Project Leaders,
This project was initiated under Task IX, Identification and Quan-
tification of Toxic and Hazardous Emissions from Chemical Plants,
of Contract 68-02-1320, Quick Reaction Engineering and Technical
Services (Multiple Option Services Contract); it was continued and
concluded under Contract 68-02-1874, Source Assessment.
111
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ABSTRACT
Atmospheric emissions from propylene-based acrylonitrile manu-
facturing plants are analyzed. Uncontrolled and controlled emis-
sion factors are given for each species emitted to the atmosphere
from each source within a typical plant based on field sampling
data and engineering estimates. Emissions data are used to cal-
culate several factors designed to quantify the hazard potential
of the emissions. These include the source severity (defined as
the ratio of time-averaged maximum ground level concentration of
a pollutant to an acceptable concentration), industry contribu-
tion to total atmospheric emissions of criteria pollutants, and
the population exposed to high contaminant levels from a repre-
sentative plant. A detailed process description and flow sheet
are presented for the SOHIO process. Present and future aspects
of pollution control technology in the industry are discussed.
Economic and production trends in the acrylonitrile industry and
in each of the industries that are consumers of acrylonitrile are
analyzed.
This report was submitted under Contract No. 68-02-1874 by
Monsanto Research Corporation under the sponsorship of the U.S.
Environmental Protection Agency. This report covers a period
from May 1974 to July 1976 and the work was completed as of
March 16, 1977.
IV
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CONTENTS
Preface iii
Abstract iv
Figures vii
Tables viii
Abbreviations and Symbols xi
I Introduction 1
II Summary 3
III Source Description 10
A. Process Description 10
1. Feed Materials Storage and Preparation 11
2. Processing and Product Recovery 13
3. Product Purification 20
4. Wastes Disposal 20
5. Product Storage and Transportation 23
6. Plant Shutdown, Turnaround, and Startup 25
B. Plant Material Balance 25
C. Plant Locations
IV Emissions 31
A. Selected Pollutants 31
1. Locations and Description of Emissions 31
2. Factors Affecting Emissions 32
3. Emission Factors 39
B. Definition of a Representative Source 39
C. Source Severity 39
D. Industry Contribution to Total Atmospheric Emissions 47
E. Affected Population 47
F. Trends in Acrylonitrile Plant Emissions 52
V Control Technology 54
A. State of the Art 54
B. Future Considerations 55
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CONTENTS (continued)
1. Waste-Heat Recovery Boilers 55
2. Thermal Incinerators 57
3. Catalytic Incinerators 57
VI Growth and Nature of the Industry 59
A. Process Technology 59
1. Ethylene Oxide Process 60
2. Acetylene Process 60
3. Propylene and Nitric Oxide Process 60
4. Ammoxidation of Propylene 61
5. Propane Ammoxidation 61
B. Marketing Strengths and Weaknesses 62
References 66
Appendices
A. Field Sampling Results for Absorber Vent Gas 70
B. Field Sampling Results for Incinerator Stack Gases 72
C. Field Sampling Results for Deep Well Pond Emissions 73
D. Reference 3 Data for Flare Stack Emissions 74
E. Storage Tank Emission Factor Calculations 75
F. Fugitive Emission Loss Calculations 79
G. Product Transport Loading Facility Emission Factors 80
H. Derivation of Source Severity Equations 81
I. Affected Population Calculations 94
J. Sampling and Analysis Methods Used at Acrylonitrile
Plants 96
Glossary 106
Conversion Factors and Metric Prefixes 108
VI
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FIGURES
Number Page
1 Flow diagram for a representative acrylonitrile
plant. 12
2 Cyclone section of the acrylonitrile reactor. 16
3 Locations of acrylonitrile manufacturing plants. 29
4 Products of photochemical oxidation of propylene. 32
5 Source severity distributions for uncontrolled
emissions in absorber vent gas. 48
6 Annual yearly mass of emission of criteria
pollutants from acrylonitrile manufacture. 53
7 Schematic diagram for a combination byproduct
incinerator/absorber vent gas thermal oxidizer
system. 54
8 Typical flow diagram for a CO-boiler emission
control system. 56
9 Thermal incinerator for an acrylonitrile plant. 57
10 Acrylonitrile industry growth. 59
11 Acrylonitrile markets. 63
J-l Available sampling lines at Plant A. 97
J-2 Available sampling lines at Plant B. 97
J-3 Sampling train for acrylonitrile, acetonitrile,
and hydrogen cyanide emissions. 98
J-4 Laboratory sample generation and collection
system for acrylonitrile and acetonitrile. 99
J-5 Porous polymer tube sampling train. 101
VII
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TABLES
Number Page
1 Emission Factors for Acrylonitrile Manufacture by
Emission Point (Uncontrolled Emissions) 5
2 Emission Factors for Acrylonitrile Manufacture by
Emission Point (Controlled Emissions) 6
3 Source Severities for Uncontrolled Emissions 7
4 Source Severities for Controlled Emissions 8
5 Stream Codes for Figure 1 13
6 Performance of a Pilot-Scale Acrylonitrile Reactor 15
7 Acrylonitrile Reactor System Heat Balance 18
8 Composition of Wastewater Column Bottoms 21
9 Composition of Acetonitrile Column Bottoms 21
10 Acrylonitrile Plant Wastewater 22
11 Tankage Requirements for a 121,500-metric ton/yr
Acrylonitrile Plant 24
12 Material Balance for a Representative
Acrylonitrile Plant 26
13 Acrylonitrile Plants 29
14 Suspected Emissions from Acrylonitrile Manufacture
Prior to Field Sampling 31
15 Characteristics of Measured Emissions from
Acrylonitrile Manufacture 33
16 Absorber Vent Discharges Using Catalyst 35
17 Effect of Catalyst Type on Acrylonitrile Absorber
Vent Emissions 35
18 Reported Incinerator Stack Emission Factors 36
19 Incinerator Stack Emission Factors from Field
Sampling 36
20 Hydrocarbon Emission Factors for Acrylonitrile
Deep Well Ponds 38
21 Flare Stack Emission Factors 38
Vlll
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TABLES (continued)
Number Pag<
22 Emission Factors for Acrylonitrile Manufacture by
Emission Point (Uncontrolled Emissions) 40
23 Emission Factors for Acrylonitrile Manufacture by
Emission Point (Controlled Emissions) 41
24 Plant Parameters Used in Determining the
Representative Acrylonitrile Source 41
25 Source Severity Equations 43
26 Effective Emission Heights Used to Calculate
Maximum Ground Level Concentrations 43
27 Maximum Ground Level Concentrations of Atmospheric
Emissions from Acrylonitrile Manufacture
(Controlled Emissions) 44
28 Source Severities for Uncontrolled Emissions 45
29 Source Severities for Controlled Emissions 46
30 Nationwide Emissions of Criteria Pollutants from
Acrylonitrile Manufacture 47
31 Emissions of Criteria Pollutants from
Acrylonitrile Manufacture by State 49
32 Affected Population 51
33 Annual Emissions of Criteria Pollutants from
3 Acrylonitrile Plants 52
34 Typical Material Balance for a Co-Boiler Emission
Control System 56
35 Typical Material Balance for a Thermal Incinerator
for Byproduct Streams 58
36 Effect of Catalyst Improvements on Acrylonitrile
Manufacture via Ammoxidation of Propylene 62
A-l Absorber Vent Emission Factors (Uncontrolled
Emissions) 71
B-l Incinerator Stack Gas Emission Factors 72
C-l Deep Well Pond Emission Factors 73
D-l Flare Stack Emission Factors 74
E-l Storage Tank Input Data for an Acrylonitrile
Plant (Uncontrolled Emissions) 77
E-2 Storage Tank Emissions Summary (Uncontrolled
Emissions) 78
IX
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TABLES (continued)
Number Page
F-l Fugitive Emission Losses for a Representative
Acrylonitrile Plant 79
H-l Pollutant Severity Equations for Elevated Sources 81
H-2 Values of a for the Computation of a 83
H-3 Values of the Constants Used to Estimate Vertical
Dispersion 83
H-4 Summary of National Ambient Air Quality Standards 87
1-1 Affected Population Calculations 95
J-l Distribution of Acrylonitrile and Acetonitrile in
Three Tandem Distilled Water Impingers 100
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ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
AAQS
ACN
AN
SOHIO
TLV
SYMBOLS
A
C
Cap
^i
D
S?
e
E
E1
F
H
H1
KT
L
LI
L9
Ly
MW
n
N
P
P1
Q
Q1
S
t,
T
u
—ambient air quality standard
—acetonitrile
—acrylonitrile
—The Standard Oil Company
—threshold limit value
—affected area, km2
—storage tank diameter factor
—production capacity, metric tons/yr
—production capacity of plant i, metric tons/yr
—tank/reactor diameter, m
—affected population density, persons/km2
—mean population density, persons/km2
—county population density for plant i, persons/km2
— 2.72
—emission factor, g/kg of product acrylonitrile
—emission factor, Ib/ton of product acrylonitrile
—hazard factor [primary AAQS for criteria pollutants;
adjusted TLV otherwise (TLV x 0.33 x 0.01)], g/m3
—equivalent gasoline working loss, bbl/yr
—paint factor
—effective emission height, m
—tank outage, ft
—turnover factor
—total petrochemical loss, bbl/yr
—total petrochemical loss, Ib/yr
—total equivalent gasoline loss, bbl/yr
—equivalent gasoline breathing loss, bbl/yr
—molecular weight, Ib/lb-mole
—number of plants
—number of turnovers per year
—pressure, kPa
—affected population, persons
—emission rate, g/s
—propylene ratio, moles propylene/moles of gas
—source severity
—averaging times, min
—temperature, °C (or °F as indicated)
—wind speed, m/s
XI
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ABBREVIATIONS AND SYMBOLS (continued)
SYMBOLS (continued)
u —average wind speed, m/s
v —superficial velocity, m/s
V —tank capacity, bbl
W —liquid density, lb/ft3
x —downwind distance from source, m
y —horizontal distance from centerline of dispersion, m
Y —yield, %
AT —average ambient temperature change, °F
TT —3.1416
Oy —standard deviation of vertical dispersion
az —standard deviation of horizontal dispersion
% —downwind ground level concentration, g/m3
X —average concentration, g/m3
Xmax —maximum ground level concentration, g/m3
i(max —time-averaged maximum ground level concentration, g/m3
X"(x) —annual mean ground level concentration, g/m3
XII
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SECTION I
INTRODUCTION
Acrylonitrile is an important synthetic organic chemical used in
the manufacture of acrylic fibers, nitrile rubber, and plastic
resins, and as a chemical intermediate. Present (1976) annual
production capacity in the United States is 8.62 x 105 metric
tons3 (9.5 x 105 tons). Acrylonitrile is produced by the cata-
lytic vapor phase ammoxidation" of propylene. This document
presents a detailed study of acrylonitrile manufacturing plants
from the standpoint of atmospheric emissions and their potential
environmental impact.
The major results of this study are summarized in Section II.
These results include emission factors for each species emitted
to the atmosphere from each emission point within a representa-
tive acrylonitrile plant. Also tabulated are several factors
designed to measure the environmental hazard potential of acrylo-
nitrile plant operations including: source severity, the industry
contribution to total atmospheric emissions of criteria pollutants,
the population affected by a representative plant, and future
trends in emissions'.
Section III describes the acrylonitrile manufacturing process in
detail. Discussion is limited to the SOHIO process since it is
the only one currently used in the U.S. Included are descriptions
of each major processing step, flow diagrams, process chemistry,
and material and energy balances.
Atmospheric emissions from acrylonitrile manufacturing plants are
discussed in Section IV. The species known to be emitted and/or
produced by each process step are detailed, and each emission
point within the plant is described. Compositions and flow rates
of streams emitted to the atmosphere are provided. A representa-
tive acrylonitrile plant is defined, and emission factors are
given for such a plant. These emission factors are then used to
1 metric ton = 106 grams = 2,205 pounds =1.1 short tons (short
tons are designated "tons" in this document); conversion factors
and metric system prefixes are presented at the end of this
report.
Ammoxidation is the oxidation of a chemical in the presence of
ammonia.
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determine the source severity, calculate the industry contribution
to total emissions of criteria pollutants, estimate the affected
population, and determine future trends in emissions.
Present and future aspects of pollution control technology in the
acrylonitrile industry are considered in Section V. Several pro-
cess modifications are described which have been used in recent
years and shown to have reduced the environmental impact of the
atmospheric emissions from the industry.
Production trends in the acrylonitrile industry are addressed in
Section VI. The trends in each of the industries that are major
consumers of acrylonitrile are also analyzed. Finally, estimates
of acrylonitrile production through the remainder of the present
decade are discussed.
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SECTION II
SUMMARY
Acrylonitrile is manufactured by the catalytic vapor phase ammoxi-
dation3 of propylene using the SOHIO process developed by The
Standard Oil Company (SOHIO). There are six plants operating in
the U.S. having a combined production capacity of 8.62 x 105
metric tons/yr (9.5 x 105 tons). The plants are located in rural
and nonrural counties having population densities of 29 to 1,103
persons/km2 (73 to 2,758 persons/mi2).
Sources of atmospheric emissions within acrylonitrile plants in-
clude the absorber vent, incinerator stack, flare stack, deep well
pond, storage tanks, product transport loading facility and fugi-
tive sources. Materials emitted from acrylonitrile plants include
criteria pollutants (carbon monoxide, hydrocarbons, nitrogen
oxides and sulfur oxides) and 23 chemical substances (such as
propylene, propane, acrylonitrile, acetonitrile, hydrogen cyanide,
benzene, and toluene).
The absorber vent gas consists of neutralized reactor effluent
which has been scrubbed for nitriles recovery. This stream ac-
counts for more than 99.9% of uncontrolled carbon monoxide emis-
sions and 87.3% of the uncontrolled hydrocarbon emissions.
Current methods of emissions control for these emissions involve
the use of combustion equipment which has demonstrated greater
than 95% removal of both carbon monoxide and hydrocarbons.
The incinerator stack gas consists of combustion products from
the thermal oxidation of acetonitrile waste and hydrogen cyanide
waste. Emissions from the incinerator consist of nitrogen oxides,
sulfur oxides and hydrogen cyanide. Combustion of nitrile feed
to the incinerator is greater than 99% complete; only 0.6% of
the nitrile feed is converted to NO .
H
The acrylonitrile plant flare is used for the combustion of hydro-
carbon releases from the purification section. Approximately 90%
combustion of carbon monoxide and 75% to 80% combustion of hydro-
carbons are obtained according to previous studies performed by
Houdry Division, Air Products and Chemicals, Inc.
Ammoxidation refers to the oxidation of a substance in the
presence of ammonia.
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Ultimate disposal of acrylonitrile wastewater is performed through
the use of deep injection wells. A nonaerated lagoon (deep well
pond) is used for solids removal prior to deep well injection.
The deep well pond is a source of hydrocarbon emissions due to the
volatile organics contained in the wastewater. Attempts to reduce
the hydrocarbon emissions have involved the use of a layer of lube
oil over the pond. This action reduces the deep well pond hydro-
carbon emissions by >92%.
Storage tanks contain refined and crude acrylonitrile. Available
control devices in use include conservation vents, vent condensers,
and floating roofs. Emissions from the product transport loading
facility occur during the loading of railcars and tank trucks.
Emission controls include the use of activated carbon adsorption
and refrigeration compression systems.
Fugitive emission losses occur at pump seals, flanges, gaskets,
pressure relief valves, compresser seals, and valves.
Emission factors are summarized in Tables 1 and 2 for uncontrolled
and controlled emissions from acrylonitrile plants. The absorber
vent is controlled at three acrylonitrile plants, as is the deep
well pond. None of the other emission vents are controlled at
acrylonitrile plants.
To assess the environmental impact of atmospheric emissions from
acrylonitrile manufacture, the source severity for each material
emitted from each emission point was estimated. Source severity
is defined as the pollutant concentration to which the population
may be exposed divided by an "acceptable concentration." The
exposure concentration is the time-averaged maximum ground level
concentration as determined by Gaussian plume dispersion methodol-
ogy. The "acceptable concentration" is that pollutant concentra-
tion at which an incipient adverse health effect is assumed to
occur. For criteria pollutants, it is the corresponding primary
ambient air quality standard. For noncriteria pollutants, it is a
surrogate air quality standard determined by reducing TLV's for
chemical substances using an appropriate safety factor. Source
severities were calculated for a representative plant defined as
having a production capacity of 1.4 x 105 metric tons/yr
(1.54 x 105 tons/yr).
The results show that the deep well pond has the highest source
severity (98 for total uncontrolled hydrocarbons) even though it
represents only 18.3% of the total mass of uncontrolled hydro-
carbon emissions. Its source severity is highest because the deep
well pond is a ground level source while all other emission points
are elevated point sources.
The maximum source severity for the elevated point sources is 10.4
for uncontrolled hydrocarbon emissions from the absorber vent.
Propylene and propane comprise 96% of the hydrocarbons in the
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TABLE 1. EMISSION FACTORS FOR ACRYLONITRILE MANUFACTURE BY EMISSION POINT (UNCONTROLLED EMISSIONS)
(g/kg of acrylonitrile produced]
Material emitted
Criteria pollutants
Carbon monoxide
Hydrocarbons (aa diii)
Nitrogen oxides
Sulfur oxides
P articulates
Absorber Incinerator
vent stack
79.3 ± 6% 0.0040 ± 104
57.1 ± 7% 0.0203 + 428%
- 100%
0.542 + 107%
- 100%
0.176 ± 59%
Emission point
Product
transport
Flare Deep well Fugitive loading Storage
stack pond emissions facility tanks
0.268 13 ± 61% 0.00038 ± 20% 0.0055 ± 20% 0.661 ± 20%
0.01
Chemical substances
Methane
Ethane
Ethylene
Propane and propylene
Butene
Benzene
Toluene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Fumaronitrile
Pyridine
Propionaldehyde
Fur an
Ammonia
Allyl alcohol
0.67 ± 6% 0.0023 ± 10%
1.93 ± 92%
2.57 ± 81%
55.0 ± 60% 0.022 0.000006 i 20%
0.400 ± 50%
0.146 ± 50%
0.065 ± 50%
0.039 t 41% <0.0015 0.039 0.00042 ± 20% 0.0065 ± 20* O.BO2 ± 20%
0.625 i 49% <0.0015 0.000024 ± 20%
0.275 i 22% 0.0343 + 428% 0.35
- 100%
0.036
5.2 ± 74%
0.0061 1 50%
0.467 ± 50%
0.000006 t 20%
0.024 ± 50%
Emission factors for total hydrocarbons do not equal the sun of emission factors for all organic materials except methane.
To determine the hydrocarbon emission, the methane equivalent emission factors (based on carbon) for each nonmethane
organic material are calculated and then sunned. (Statement applies to all emission points except deep well pond where
7.8 g/kg of material [two species] were unidentifiable.)
Note: Blanks indicate no emissions present.
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TABLE 2. EMISSION FACTORS FOR ACRYLONITRILE MANUFACTURE
BY EMISSION POINT (CONTROLLED EMISSIONS)
(gAg)
Emission point
Material emitted
Absorber vent
Deep well pond
Criteria pollutants
Carbon monoxide <4.0
Hydrocarbons <2.86
Nitrogen oxides
Sulfur oxides
Particulates
Chemical substances
Methane <0.03
Ethane <0.1
Ethylene <0.1
Propane and propylene <3.0
Butene <0.02
1.1 + 117%
- 100%
Butane
Methanol
Pentane
Acetaldehyde
Hexane
Ethanol
Benzene <0.07
Toluene < 0.00 3
Acrylonitrile <0.002
Acetonitrile <0.03
Hydrogen cyanide <0.01
Propionaldehyde <0.0003
Furan <0.02
Allyl alcohol <0.001
0.06 + 182%
- 100%
0.16 + 138%
- 100%
0.04 + 172%
- 100%
0.06 + 422%
- 100%
0.04 + 145%
- 100%
0.1 + 345%
- 100%
0.1 + 150%
- 100%
0.02 + 222%
- 100%
Note: Blanks indicate no emissions present.
*/*^MMl»w4*h1 f* £ £ 4 *+ 4 ******* r 4 t* ^ O CO. f AW ^V% A w»*«a 1 *"Nv •! *^ n •» A. v*e f\V
catalytic incinerators for the carbon monoxide and hydro-
carbon emissions from absorber vent.
Control efficiency is 92% when using a lube oil covering
on pond for control of hydrocarbons.
6
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absorber vent gas. For absorber vents using thermal oxidizers to
control hydrocarbon emissions, the hydrocarbon source severity is
<0.52 when obtaining >95% removal of the hydrocarbons. Source
severities for uncontrolled and controlled emissions are shown in
Tables 3 and 4.
TABLE 3. SOURCE SEVERITIES FOR UNCONTROLLED EMISSIONS
Emission point
Material emitted
Absorber
vent
Incinerator
stack
Flare
stack
Deep well
pond3
Fugitive
emissions
Product
transport
loading
facility
Storage
tanks
Criteria pollutants
Carbon monoxide
Hydrocarbons'1 »c
Nitrogen oxides
Sulfur oxides
Particulates
Chemical substances
0.07
10.4
0.000013
0.002
0.48
0.0035
0.075
0.0023
98
0.0039 0.0040 2.48
Methane
Ethane
Ethylene
Propane and propylene
Butene
Acetaldehyde
Benzene
Toluene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Fumaronitrile
Pyridine
Propionaldehyde
Furan
Ammonia
Allyl alcohol
0.0058 0.000051
0.0088
0.013
0.18 0.0001 0.000001
0.0010
H
0.03
0.001
0.0054 0.00073 0.0054 0.0028 0.043 1.70
0.055 0.00047 0.000048
0.15 0.068 0.200 e
-
202
0.013
0.145
0.000035
0.030
Occurs on plant property.
Hydrocarbons include all organic materials except methane.
Total source severity for nonmethane organic materials will not equal the source severity for hydro-
carbons. Source severities for the organic chemicals are based on the toxicity of the chemicals. The
hydrocarbon source severity is based on the toxicity of oxidants, which are the products of the photo-
chemical degradation of the organic chemicals.
Using a TLV of 10~6 g/m3 for suspected carcinogens, as defined by EPA, the source severity for benzene
becomes 900.
Indeterminate since a TLV does not exist for this material.
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TABLE 4. SOURCE SEVERITIES FOR CONTROLLED EMISSIONS
Emission point
Material emitted
Absorber vent
Deep well pond
bTc
Criteria pollutants
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Particulates
Chemical substances
Methane
Ethane
Ethylene
Propane and propylene
Butene
Butane
Methanol
Pentane
Acetaldehyde
Hexane
Ethanol
Benzene
Toluene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Propionaldehyde
Furan
Allyl alcohol
<0.0035
<0.52
<0.005
<0.00044
<0.00065
<0.009
<0.00005
<0.0015d
<0.00005
<0.00027
<0.048
<0.0075
<0.00065
<0.0073
<0.0015
7.8
0.0068
0.18
0.0065
0.097
0.032
0.015
0.15e
0.016
Note: Blanks indicate no emissions presenb.
a
Control efficiency >95% for thermal oxidizers or catalytic
incinerators for the carbon monoxide and hydrocarbon
emissions from absorber vent.
Control efficiency >92% when using a lube oil covering on
pond for control of hydrocarbons.
Occurs on plant property.
Using a TLV of 10~6 g/m3 for suspected carcinogens, as
defined by EPA, the source severity for benzene is <4.5.
Using a TLV of 10~6 g/m3 for suspected carcinogens, as
defined by EPA, the source severity for benzene becomes 300
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Atmospheric emissions of criteria pollutants from acrylonitrile
plants in the U.S. in 1976 amount to 26,900 metric tons (29,600
tons) of carbon monoxide, 24,900 metric tons (27,400 tons) of
hydrocarbons, 470 metric tons (517 tons) of nitrogen oxides, and
15.0 metric tons (16.5 tons) of sulfur oxides. These values equal
0.03%, 0.15%, 0.005%, and <0.001%, respectively, of the total U.S.
emissions of carbon monoxide, hydrocarbons, nitrogen oxides, and
sulfur oxides from stationary sources.
Hydrocarbon emissions from acrylonitrile manufacture in Louisiana,
Ohio, Tennessee, and Texas amounted to 0.64%, 0.78%, 3.57%, and
0.12% of the total hydrocarbon emissions of these states, respec-
tively. Carbon monoxide emissions from acrylonitrile manufacture
in Louisiana, Ohio, Tennessee, and Texas amounted to 0.97%, 0.05%,
4.62%, and 0.115%, respectively.
Acrylonitrile production in 1973 was 6.13 x 105 metric tons
(6.74 x 105 tons) and is expected to be 1.3 x 106 metric tons
(1.4 x 106 tons) in 1978. This represents an increase of 112%
over the 5-year period. During this period, the national masses
of carbon monoxide and hydrocarbon emissions from the absorber
vent are expected to decrease 58% and 56%, respectively, because
of state regulations controlling these emissions.
The number of persons that may be exposed to concentrations above
the primary ambient air quality standard3 for uncontrolled hydro-
carbon emissions from the representative acrylonitrile plant is
13,300. Approximately 96% of this exposure is due to propylene
and propane. When controlling hydrocarbons by 95%, the number of
persons possibly exposed to concentrations exceeding the primary
ambient air quality standard is zero. Based on the definition of
source severity for chemical substances in this document, no
persons are exposed to concentrations of nitrile emissions exceed-
ing 0.0033 times the threshold limit value, g/m3.
aThere is no primary ambient air quality standard for hydrocarbons,
The value of 160 ug/m3 used for hydrocarbons in this report is a
recommended guideline for meeting the primary ambient air quality
standard for photochemical oxidants.
9
-------
SECTION III
SOURCE DESCRIPTION
A. PROCESS DESCRIPTION
Acrylonitrile, a colorless liquid with a mild odor, freezes in
the range of -83°C to -84°C and boils in the range of 77.3°C to
77.4°C. Synonyms for acrylonitrile include propenenitrile and
vinyl cyanide. The structure of acrylonitrile is:
Acrylonitrile can be produced using the following methods:
(1) oxidation of propylene in the presence of ammonia (ammoxida-
tion of propylene) using either a bismuth phosphomolybdate or
uranium-based catalyst; (2) addition of hydrogen cyanide to acetyl-
ene using a cuprous chloride catalyst; (3) catalytic reaction of
propylene with nitric oxide; (4) reaction of ethylene oxide with
hydrogen cyanide followed by catalytic dehydrogenation of ethylene
cyanohydrin; and (5) ammoxidation of propane.1'2
Each of the first four processes listed above has been used commer-
cially, and ammoxidation of propane has been studied on a pilot
scale. However, since 1971 the ammoxidation of propylene is the
only process which has been used commercially. The process is
patented by The Standard Oil Company (SOHIO) and is known as the
SOHIO process.
G. G. The Condensed Chemical Dictionary, Eighth Edition
Van Nostrand Reinhold Company, New York, New York, 1971. p. 15.
2Kirk-Othmer Encyclopedia of Chemical Technology, Second Edition,
Vol. 1. John Wiley & Sons, Inc., New York, New York, 1969.
pp. 338-351.
10
-------
This source description will be limited to the SOHIO process
because it is the only commercial process in use. Figure 1 is a
schematic flow diagram for a representative acrylonitrile plant.3
Streams numbered in Figure 1 are defined in Table 5. The process
consists of the following steps: (1) feed materials storage and
preparation; (2) processing and product recovery; (3) product
purification; (4) wastes disposal; and (5) product storage and
transportation. Each of these topics is described in the fol-
lowing subsections.
1. Feed Materials Storage and Preparation
Feed materials used in the acrylonitrile process are propylene,
ammonia, and air.
Propylene feed (stream 1 in Figure 1) consists of a propylene/
propane mixture with a propylene content of 90% to 97% on a mass
basis (personal communication, T. W. Hughes of Monsanto Research
Corporation and J. Killen of Vistron Corporation, October 3, 1974).
The source of propylene is either refinery production or steam
crackers which are located near each plant site. Propylene is
stored as a liquid at its vapor pressure of 1,050 kPa at 21°C.
This feed is vaporized and preheated using process steam prior to
use for acrylonitrile manufacture.
Agricultural-grade ammonia3 (stream 2) of the following composi-
tion1* is used in the manufacture of acrylonitrile:
Component Amount
Ammonia 99.8% by wt (minimum)
Water 0.015% by wt (maximum)
Oil 3 ppm (maximum)
Noncondensable gas 0.0002 m3/kg (maximum)
The ammonia is stored as a liquid at its vapor pressure of 890 kPa
at 21°C. It is vaporized and preheated using process steam prior
to use.
Air (stream 3) is filtered and compressed prior to use.
3Schwartz, W. A., F. B. Higgins, Jr., J. A. Lee, R. Newirth, and
J. W. Pervier. Engineering and Cost Study of Air Pollution Con-
trol for the Petrochemical Industry. Volume 2: Acrylonitrile
Manufacture. EPA-450/3-73-006-b, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina. February 1975.
103 pp.
^Considine, D. M. Chemical and Process Technology Encyclopedia.
McGraw-Hill Book Company, New York, New York, 1974. p. 108.
11
-------
WASTE HEAT
BOILER
COOLING COILS
$ Y
s * 9—
STEAM
DEEP WELL
POND
DENOTES MAIN PRODUCT FLOW
DENOTES ALL OTHER STREAM FLOW
TO DEEP WELL
CRUDE
ACRYLONITRILE
••j STORAGE [-1
A
®
ABSORBER VENT GAS
FLARE
FUGITIVE EMISSIONS
INCINERATOR STACK GAS
-*- DEEP WELL POND EMISSIONS
STORAGE TANK EMISSIONS
PRODUCT^
ACRYLONITRILE
•H STORAGE
PRODUCT TRANSPORT LOADING
FACILITY VENT
PRODUCT TRANSPORT
LOADING
FACILITY
TANK TRUCK
RAILROAD CAR
Figure 1. Flow diagram for a representative acrylonitrile plant.3
-------
TABLE 5. STREAM CODES FOR FIGURE 1
Stream number Description
1 Propylene feed
2 Ammonia feed
3 Process air
4 Reactor feed
5 Reactor product
6 Cooled reactor product
7 Quenched reactor product
8 Sulfuric acid
9 Stripping steam
10 Wastewater column volatiles
11 Wastewater column bottoms
12 Absorber vent gas
13 Acrylonitrile plant wastewater
14 Absorber bottoms
15 Water recycle
16 Crude acetonitrite
17 Crude acrylonitrile
18 Recovery column purge vent
19 Acetonitrite column bottoms
20 Acetonitrile
21 Hydrogen cyanide
22 Light ends column purge vent
23 Light ends column bottoms
24 Product acrylonitrile
25 Heavy ends
26 Product column purge vent
27 Flare
28 Fugitive emissions
29 Incinerator stack gas
30 Deep well pond emissions
31 Storage tank emissions
32 Product transport loading facility vent
2. Processing and Product Recovery
a. Reactor—
In the SOHIO process, propylene/ammonia/air reactants are fed in
approximately the molar ratio of 1/1.06/8.40.3 Stoichiometric
proportions would be 1/1/7.14 as dictated by the chemical equation:
CH2CHCH3 + NH3 + 1.502 + 5.64N2 •* CH2CHCN + 3H20 + 5.64N2 (1)
However, 3% excess ammonia is used to force the reaction toward
completion, and 18% excess air is used to continuously regenerate
the catalyst.3
13
-------
The reactants are fed continuously to the reactor, which operates
at 135 kPa to 310 kPa at 400°C to 510°C. This is a gas fluidized
bed reactor in which the catalyst is the solid phase and the
reactants and products comprise the vapor phase.
Details of the reactor design have not been published in domestic
technical journals. However, two SOHIO patents describe the
reactor design (U.S. 3,427,3435 and Belgian 700,6416). The U.S.
patent states that stacked multistage fluidized bed reactors
having at least four catalyst compartments are preferred. In each
compartment the catalyst is fluidized by passing gases through
trays having 33% open area provided by 4.8-mm diameter holes.
Catalyst fines are collected by internal cyclones at the top of
the reactor and returned to the lowest catalyst compartment.
Propylene and ammonia are introduced into the third catalyst
compartment from the bottom while air is added to the lowest
catalyst compartment. Sufficient air is used to maintain 2% to 3%
oxygen concentration in the reactor effluent gases. By using the
lower compartments for contacting the catalyst with oxygen and by
controlling the outlet oxygen concentration, catalyst regeneration
becomes continuous.
The performance of a 3.3-m diameter, 10-stage reactor using a
uranium-based catalyst (catalyst 21) is described in the patent.5
The catalyst has the physical properties shown in Table 6. When
reactor conditions were changed to allow the ammonia and propylene
to enter with the air in the lower compartment, the yield began
dropping almost immediately.5
The second SOHIO patent6 describes details of the upper part of
the reactor where the solid is disengaged from the gas. If this
part of the reactor is incorrectly designed, masses of catalyst
will adhere to the upper metal surface. Because of poor gas cir-
culation through the mass, temperatures will rise and damage the
catalyst. Catalyst chunks may break off and fall into the dense
bed below, causing inefficient reaction conditions with attendant
loss of yield. In the preferred reactor design shown in Figure 2,
nitrogen is added to the uppermost chamber and flows through the
cyclone support plate. Nitrogen and the reaction gases from the
compartments below are then discharged into a series of three
cyclones where catalyst is removed and returned to the reactor
below, while the gases are allowed to exit.
5Callahan, J. L., E. C. Milberger, and R. K. Grasseli. Process
for Preparing Olefinically Unsaturated Aldehydes and Nitriles.
U.S. Patent 3,427,343 (to The Standard Oil Company),
February 11, 1969.
6Callahan, J. L., R. D. Presson, and A. F. Miller. Cylindrical,
Vertical, Fluidized Solid Reactor. Belgian Patent 700,641 (to
The Standard Oil Company), December 28, 1967.
14
-------
TABLE 6. PERFORMANCE OF A PILOT-SCALE ACRYLONITRILE REACTOR 5
Catalyst Properties
PropertyValue
Apparent bulk density 1,196 kg/m3
Compact bulk density 1,361 kg/m3
Pore volume 0.000218 m3/kg
Surface area 18 m2/g
Catalyst Particle Size Distribution
Particle size, pmWeight %Cumulative weight %
>_105
<105 to
<88 to
<74 to
<63 to
<53 to
<44
88
74
63
53
44
16
12
21
7
6
19
19
16
28
50
56
62
81
100
Reactor Performance Data
Temperature = 480°C
Contact time = 10 s
Pressure = 205 kPa
Hours on stream
6
11
20
28.5
75
95
Yield,3 %
67.3
66.9
66.9
67.1
67.4
68.2
Yield is defined as the kilograms of carbon in acrylo-
nitrile product divided by the kilograms of carbon in
the propylene feed, and expressed as a percent.
15
-------
REACTOR EFFLUENT
NITROGEN
GAS ENTRANCE TO
FIRSTSTAGEOFxJ
THREE-STAGE
CYCLONE
>TAT!CBED
HEIGHT
Figure 2. Cyclone section of the acrylonitrile reactor.
16
-------
Test data were obtained on a 3.3-m diameter multistage reactor
operating at a 0.45 m/s superficial vapor velocity and using the
catalyst described in U.S. Patent 3, 198, 7 50. 7 Propylene, ammonia,
and air (1/1.15/10.5 molar ratio) were reacted at 493°C to 500°C
and approximately 219 kPa. When no inert gas was added to the
upper compartment, the temperature increased to ^538°C and the
yield declined to 60% to 63%. Deposits were found on reactor
internals. 7
When nitrogen was added to the upper compartment, the temperature
remained normal and the yield was 66% to 68% at a 90% to 95% con-
version5 over an extended period. Catalyst loss from the reactor
did not exceed 45 kg/day (1.9 g/kg) after stable conditions were
achieved.
Using the data supplied in the above patent7 for the 3.3-m diam-
eter reactor, the annual operating capacities for the operations
discussed above were calculated. The capacity at 68.2% yield was
8,400 metric tons/yr and the capacity at 63% yield was 7,800
metric tons/yr assuming an on-stream factor of 90% for 360 days/
yr. These capacities were determined in the following manner:
where v = superficial velocity, 0.45 m/s
D = reactor diameter, 3.3 m
P = absolute pressure, 219 kPa
T = absolute temperature, 766°K
R = gas law constant, 8.31 x 10~3 (kPa)m3/(g-mole) K
MW = propylene molecular weight or 42 g propylene/g-mole
Q1 = propylene ratio or 1 mole propylene/12. 65 moles gas
Y = yield, 68.2% or 63%
The above reactor description is based upon the best information
available from the literature. Further details of reactor design
are considered proprietary by SOHIO (personal communication,
T. W. Hughes of Monsanto Research Corporation and J. Killen of
Vistron Corporation, October 3, 1974) and are not available.
b. System Heat Balance —
The ammoxidation of propylene is an exothermic chemical reaction
which has a heat release of 17.6 kJ/g acrylonitrile formed. Side
reactions which occur in the reactor due to by-product formation
and catalyst regeneration also liberate heat. The heat release
due to these reactions is ^4.3 kJ/g acrylonitrile formed. The
total heat release for all reactions has been estimated to be
21.93 kJ/g acrylonitrile formed.3
7Callahan, J. L. Mixed Antimony Oxide - Uranium Oxide Oxidation
Catalyst. U.S. Patent 3,198,750 (to the Standard Oil Company),
June 27, 1967.
17
-------
Reactor temperature control is maintained by internal cooling
coils which generate ^75% of the total process steam requirements.
The remainder (^25%) of the process steam is generated in a waste
heat boiler where the product gases are cooled from 510°C to
230°C. The feed material to the waste heat boiler is the reactor
product (stream 5). Table 7 shows a typical heat balance for an
acrylonitrile plant.
TABLE 7. ACRYLONITRILE REACTOR SYSTEM HEAT BALANCE3»3
Heat out kJ/g acrylonitrile
Steam generation
Cooling coils inside reactor 15.66
Waste heat boiler 5.02
Reactor heat losses 0.10
Quench (232°C to 43°C) . 9.52
Incremental effluent heat content -2.33
TOTAL 27.97
Heat in kJ/g acrylonitrile
Exothermic heat of reaction
Acrylonitrile formation 21.93
Effluent neutralization 3.20
Feed vaporization and preheat 2.84
TOTAL 27.97
Basis: Data shown later in Table 12; feed preheated
to 149°C; reactor outlet temperature 510°C (max).
Difference in heat content of reactor product @ 43°C
and feed @ 27°C (liquid) plus air @ 38°C.
c. Quencher--
Cooled reactor effluent (stream 6) is sent to a quencher for
additional cooling and for ammonia and catalyst fines removal. A
SOHIO patent (U.S. 3,468,6248) describes the scrubbing of reactor
effluent gases with dilute sulfuric acid for the removal of excess
ammonia.
The quencher operates at 40°C to 50°C and 135 kPa to 205 kPa.
Streams entering the quencher are the cooled reactor effluent
(stream 6), sulfuric acid (stream 8), and the wastewater column
volatiles (stream 10). Stream 7 is the quenched reactor effluent.
Miller, A. F., and M. L. Salehar. Process for the Recovery of
Ammonium Salts from Waste Streams in an Acrylonitrile Plant.
U.S. Patent 3,468,624 (to The Standard Oil Company), September
23, 1959.
18
-------
Bottoms from the quencher are fed to a wastewater column where the
volatile components of this stream are stripped using steam
(stream 9). Stream 11 (wastewater column bottoms) is sent to the
deep well pond.9
The recovery of ammonium sulfate crystals by evaporation of water
from the bottoms has been unsuccessful previously because organic
material ("heavies") also precipitates and plugs the equipment.
The precipitation of the organic material has been prevented by
adding ammonium hydroxide and controlling pH to 9.8. After par-
tial evaporation, the solution can be saturated with ammonia to
precipitate a 98.3% pure ammonium sulfate salt.10 Recovery of
ammonium sulfate is not currently practiced due to a small market
demand for this material.
d. Absorber—
The acrylonitrile product and by-products (hydrogen cyanide and
acetonitrile) are recovered in a tray-type absorber tower (per-
sonal communication, T. W. Hughes of Monsanto Research Corporation
and J. Killen of Vistron Corporation, October 3, 1974) which can
be operated either with or without auxiliary cooling. (Personal
communication, T. W. Hughes of Monsanto Research Corporation and
J. Killen of Vistron Corporation, October 3, 1974.) Operation of
the absorber at low temperatures (4°C versus 43°C) increases
acrylonitrile recovery. Water, used as the absorption medium,
enters the top of the tower. The gas stream entering the bottom
of the tower, quenched reactor product (stream 7), is scrubbed to
remove acrylonitrile, acetonitrile, and hydrogen cyanide. The
absorber vent gas (stream 12) is vented to the atmosphere or sent
to a thermal oxidizer or catalytic incinerator.3
e. Recovery Column—
The absorber bottoms (stream 14) are sent to a recovery column for
separation of crude acrylonitrile (stream 17) and crude aceto-
nitrile stream 16). The crude acrylonitrile stream contains ^80%
acrylonitrile and ^12% hydrogen cyanide with the balance being
water and organics.9/J° This stream is sent to a storage tank
prior to purification.
f. Acetonitrile Column—
The crude acetonitrile (stream 16) is sent to the acetonitrile
column. This stream is separated into acetonitrile (stream 20),
9Fitzgibbons, W. 0., E. M. Schwerko, and A. H. Brainard. Deep
Well Disposal Process for Acrylonitrile Process Wastewater.
U.S. Patent 3,734,943 (to The Standard Oil Company), May 22, 1973.
10Halvorson, D. 0., and S. N. Vines. Anti-Foulant in Acrylonitrile
Manufacture. U.S. Patent 3,691,226 (to E. I. du Pont de Nemours
and Company), September 12, 1972.
19
-------
water recycle (stream 15), and acetonitrile column bottoms (stream
19). Acetonitrile is incinerated; the water recycle is returned
to the top of the absorber; and the acetonitrile column bottoms
are sent to the deep well pond.9
3. Product Purification
Product purification is normally used to upgrade crude acrylo-
nitrile to a saleable product. However, one plant currently also
produces a saleable acetonitrile product from crude acetonitrile.3
(Personal communication, T. W. Hughes of Monsanto Research Corpora-
tion and J. Killen of Vistron Corporation, October 3, 1974.)
Since four of the five operating plants do not produce aceto-
nitrile for sale, discussion of product purification will be
limited to acrylonitrile purification.
a. Light Ends Column—
Crude acrylonitrile (stream 17) is fed from tank storage to the
light ends column to remove low boiling materials. Two process
streams leave the column: (1) light ends column bottoms (stream
23); and (2) hydrogen cyanide (stream 21). The light ends column
bottoms are sent to the product column while the hydrogen cyanide
is incinerated or sold as a by-product.
b. Product Column—
Light ends column bottoms (stream 23) are fed to the product
column. Streams leaving this column consist of product acrylo-
nitrile (stream 24) and product column bottoms or heavy ends
(stream 25). The product acrylonitrile stream is 99+% pure while
the heavy ends stream contains organic polymers, water, hydrogen
cyanide, and miscellaneous organics.
4. Wastes Disposal
Wastes generated within an acrylonitrile plant consist of gaseous
wastes (including those discussed in Section IV), liquid wastes
(wastewater column bottoms, acetonitrile column bottoms, heavy
ends, crude acetonitrile, and hydrogen cyanide), and solid wastes
(catalyst fines and organic polymers). These wastes are disposed
of using deep well injection for some liquid wastes, a settling
pond for solid wastes, and incineration for the remaining liquid
and gaseous wastes. The following equipment is used for wastes
disposal: (1) deep well pond (settling pond) with deep well
injection, (2) flare, and (3) thermal oxidizer (incinerator).3
a. Deep Well Pond and Deep Well Injection—
Wastewater generated within the acrylonitrile plants contains
ammonium sulfate, catalyst fines, organic polymers, and miscel-
laneous organic materials. Sources of wastewater include waste-
water column bottoms and acetonitrile column bottoms as described
previously.
20
-------
The two wastewater streams generated in the plant (streams 11 and
19) are mixed and sent to a deep well pond (stream 13). The
composition of these two streams are given in Tables 8 and 9
as reported in Reference 9.
TABLE 8. COMPOSITION OF WASTEWATER COLUMN BOTTOMS9
~ Component Concentration, wt %
Water 85.1
Ammonium sulfate 8.1
Acrolein-(NHi,) 2 SO^ reaction product 0.4
Heavy organic material 6.1
Acrylonitrile 0.02
Acetonitrile 0.3
Maleonitrile 0.2
Fumaronitrile 0.08
TABLE 9. COMPOSITION OF ACETONITRILE COLUMN BOTTOMS9
Component Concentration, wt %
Water 98.2
Ammonium sulfate 0.02
Heavy organic material 1.74
The acrylonitrile plant wastewater (stream 13) has the appearance
of strong tea or coffee.8 Table 10 shows the composition of
acrylonitrile plant wastewater as reported by Reference 11 and a
personal communication with Arthur W. Busch, Regional Administra-
tor, Region IV, U.S. Environmental Protection Agency, February
1974.
These liquids (stream 13) are sent to a deep well pond for sepa-
ration of solids from the water. The pond typically is 60 m by
90 m in size and may be uncovered or covered with a layer of lube
oil. Heavy oil is used to limit emission of hydrocarbon vapors
from the pond surface. Runoff from the settling pond is disposed
of using deep well injection. Solids collected from the deep well
pond are disposed by a regulated, EPA-approved, landfill operator.3
L1Train, R. E. Development Document for Interim Final Effluent
Limitations and New Source Performance Standards for the Signifi-
cant Organic Products Segment of the Organic Chemicals Manufac-
turing Point Source Category. EPA-400/1-75/045, U.S. Environ-
mental Protection Agency, Washington, D.C., November 1975. 391 pp.
21
-------
TABLE 10. ACRYLONITRILE PLANT WASTEWATER3'
Material discharged
Concentration,
mg/1
Effluent factor,
q/kg
Raw wastewater
Biological oxygen demand
Chemical oxygen demand
Total organic carbon
Total solids
Total suspended solids
Total dissolved solids
Oil and grease
Total nitrogen (as N2)
Ammonia nitrogen (as N2)
Nitrile nitrogen (as N2)
Phosphate
Phenol
Sulfate
Zinc
Chloride
Iron
Copper
Chromium
Cadmium
_b
8,620
32,800
14,400
36,700 to 57,800
184 to 630
36,500 to 57,200
135 to 168
4,040 to 22,000
2,600 to 13,600
197 to 270
0.152 to 6.15
0.165 to 2.28
2,700 to 5,309
0.052 to 2.1
125 to 858
3.13 to 4.24
SO. 5
10.05
^0. 05
4,470
38.7
133
57.5
163 to 182
0.915 to 1.78
161 to 181
0.475 to 0.657
16.9 to 62.1
10.3 to 38.3
0.755 to 0.97
0.0004 to 0.0298
0.0007 to 0.0064
64.1 to 74.3
0.00002 to 0.0092
0.616 to 2.42
0.0088 to 0.0182
10.00024
10.00014
<0.00024
Other compounds which have been qualitatively identified include:
Acetaldehyde
Acrolein
Hydrogen cyanide
Acetic acid
Fumaronitrile
Acrylic acid
Acrylamide
AeryIonitrile
Acetonitrile
Maleonitrile
Organic polymers
Propionitrile
Ammonium formate
Methacrylonitrile
trans-Crotonitrile
cis-Crotonitrile
Allyl cyanide
Benzonitrile
Nicotinonitrile
Malononitrile
Furonitrile
Ticoline
Lutidine compounds
Benzene
Toluene
Ammonium acetate
Ammonium methacrylate
Ammonium acrylate
Succinonitrile
Acetone
Acetaldehyde cyanohydrin
Acetone cyanohydrin
Acrolein cyanohydrin
Pyrazole
Methyl pyrazine
Cyanopyrazine
Pyrazine
Personal communication, A. W. Busch, Regional Administrator,
Region IV, U.S. Environmental Protection Agency, February 1974.
}Not applicable.
22
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b. Flare—
The process flare, using a natural gas pilot flame, is fed by
purge vents from the recovery column (stream 18), light ends
column (stream 22), and the product column (stream 26). During
absorber upsets, flaring of propylene occurs. These periods last
for less than 5 minutes. Steam is continuously supplied to the
tip of the flare and the quantity is varied as needed to control
smoke formation.3
During plant upset or other emergencies, the following streams are
diverted to the flare:3
• Propylene Storage - Tank relief valves discharge to
the flare when the storage temperature exceeds the
design storage temperature (usually 38°C).3
• Propylene Feed - Propylene is vented to the flare if
the source of heat for feed vaporization is lost and
freezeup of the vaporizer occurs (about once every 2
years, with the venting lasting about 2 hours with
propylene loss ^0.35 kg/kg of acrylonitrile). In
addition, the venting of vaporizers to the flare
during scheduled annual shutdown results in venting
propylene (^0.09 g/kg).3
c. Incinerator—
By-product acetonitrile and hydrogen cyanide are incinerated in
a thermal oxidizer. A description of this unit is given in
Section IV.
5. Product Storage and Transportation
The tankage requirements for a 140,000-metric ton acrylonitrile
plant are summarized in Table 11 (personal communication,
A. F. Pier of Monsanto Company and L. B. Evans of the U.S. Environ-
mental Protection Agency, June 19, 1972) . Fixed roof storage
tanks are used to store acrylonitrile product (in run-down tanks
and long-term storage), off-specification acrylonitrile, crude
acrylonitrile (in surge tanks used to store feed to product purifi-
cation section of plant), and crude acetonitrile (in surge tanks
used to store acetonitrile prior to incineration).
Acrylonitrile is transported to the customer by one of four meth-
ods: railroad tank car, tanker truck, barge, or 0.21-m3 (55-gal)
drums. Acrylonitrile is loaded on railroad tank cars and tanker
trucks by means of loading racks.12
12Air Pollution Engineering Manual, Second Edition. J. A. Daniel-
son, ed. Publication No. AP-40, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina, May 1973. 987 pp.
23
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TABLE 11. TANKAGE REQUIREMENTS FOR A 121,500-METRIC
TON/YR ACRYLONITRILE PLANT3»b
Capacity,TurnoversVent height,
Stored material m^ per yr m
Acrylonitrile
Acrylonitrile
Acrylonitrile
Acrylonitrile
Acrylonitrile
Of f -specif icat ion
acrylonitrile
Crude acrylonitrile
Crude acrylonitrile
114
114
1,700
1,700
1,700
473
871
871
450
450
25
25
25
5
2
2
15.2
15.2
15.2
15.2
15.2
15.2
15.2
15.2
All tanks use conservation vents.
Personal communication, A. F. Pier of Monsanto Company
and L. B. Evans of the U.S. Environmental Protection
Agency, June 19, 1972.
Loading racks contain equipment to meter and deliver products into
tank vehicles from storage either by overhead filling through the
top hatch in the tank vehicle or by bottom filling at ground level.
The elevated platform structure employed for overhead filling, con-
structed with hinged side platforms attached to the sides of a cen-
tral walkway, can be raised when not in use. For loading, a tank
vehicle is positioned adjacent to the central walkway and a hinged
side platform is lowered to rest upon the top of the tank vehicle
to access the top hatch. The meters, values, loading tubes or
spouts, motor switches, and similar necessary loading equipment
are located on the central walkway. Bottom loading facilities are
simpler since the tank vehicle is easily filled through accessible
fittings on its underside.
Acrylonitrile is loaded on barges at modern terminals by equipment
similar to that used for elevated tank vehicle loading except for
size. A pipeline manifold with flexible hoses is used for loading
at older terminals. Marine installations are considerably larger
and operate at much greater loading rates than inland loading
facilities.
The loading arm assembly refers to the equipment at the discharge
end of a product pipeline that is necessary for filling tank vehi-
cles. Component parts include piping, valves, meters, swivel
joints, fill spouts, and vapor collection adaptors.
Overhead loading arms can be pneumatic, counterweighted, or ten-
sion spring depending upon the manner in which the vertical move-
ment of the arm is achieved. Bottom loading employs a flexible
24
-------
hose or a nonflexible, swing-type arm connected to the vehicle
from the ground level storage facility.
Loading arms at modern marine terminals are similar in design to
those used for overhead loading of tank vehicles. The barge load-
ing arms are too large for manual operation, requiring a hydraulic
system to effect arm motion. Older installations use reinforced
flexible hoses to convey products from pipeline discharge mani-
folds to the barge. The hoses are positioned by means of a winch
or crane.
6. Plant Shutdown, Turnaround, and Startup
Each acrylonitrile plant schedules shutdowns, turnarounds, and
startups for each major piece of processing equipment (reactors,
absorber, fractionation columns, and storage tanks) to permit
the necessary vessel and tank maintenance.*
Acrylonitrile reactors are shut down frequently. Plants contain
two to six reactors and each reactor undergoes shutdown, turn-
around, and startup on an average of four times per year. Each
reactor startup lasts about 1 hour, during which time effluent
from the reactor bypasses the absorber and is discharged directly
to the atmosphere. The gases discharged consist of natural gas
combustion products.3
Other processing equipment normally undergoes shutdown, turn-
around, and startup once every 12 to 14 months. Prior to entry
by plant personnel, the equipment is purged of hazardous liquids
and gases. Hydrocarbon vapors contained in the purge gas are in-
cinerated to control hydrocarbon emissions.3
B. PLANT MATERIAL BALANCE
Figure 1, presented earlier, shows the flow diagram for a repre-
sentative acrylonitrile plant. Table 12 contains a material
balance for such a plant.
Sources of atmospheric emissions from acrylonitrile plants are:
absorber vent (stream 12), incinerator stack (stream 29), flare
stack (stream 27), deep well pond (stream 30), product and by-
product storage (stream 31), transport loading facility (stream
32), and fugitive emissions (stream 28).
C. PLANT LOCATIONS
Four companies manufacture acrylonitrile at six locations in the
U.S. Table 13 lists the manufacturers and plant capacities. Fig-
ure 3 shows the plant locations. The number of processing units
(individual plants) at each location is also given in Table 13.
The population densities in the counties surrounding the plants
were calculated by dividing the county population by the county
area for the 1970 census. For those cases where a plant was
25
-------
TABLE 12. MATERIAL BALANCE FOR A REPRESENTATIVE ACRYLONITRILE PLANT
Stream number
1
234
5
6
7
8 11
12
Description
Component
Nitrogen
Oxygen
Carbon dioxide
Water
Propylene
Propane
Ammonia
Carbon monoxide
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Sulfuric acid
Ammonium sulfate
Propylene
feed
1,289
22
Ammonia Process Reactor
feed air feed
2.5C 5,865d 5,867
1,561 1,561
83.5 83.5
1,289
22
553.1 553.1
Oxygenated hydrocarbons
Organic polymers
TOTALS
1,311
556 7,510 9,375
Reactor
product
5,867
103
185
1,653
32e
226
24
178
1,000*
us!
1186
95
9,395
Cooled
reactor
product
5,867
103
185
1,653
32
22
24
178
1,000
118
118
95
9,395
Quenched
reactor
product
5,867
103
185
1,653
32
22
178
1,000
118
118
9,276
Wastewater
Sulfuric column
acid bottoms
3,470
0.9
70.6
93.2
79.3
70.6 3,643
Absorber
vent
gas5
5,867d
103
185
922
32
22
178
<0.1
0.6
0.3
7,310
(continued)
Note: Blanks indicate no component present in stream.
aAll values are g/kg of product acrylonitrile.
Emissions determined through field sampling.
c Ammonia used is agricultural grade as described in Section III. A.I.
dComposition of the combined reactor feed is based upon the following mole rates: 1 C3H6/1.06 NHa/8.4 air.
Conversion of propylene = 98*; conversion of propane = 0%; yield of acrylonitrile is 0.78 g AN/g C3H6; yield of
HCN and ACN =0.09 g/g C3H6.
-------
TABLE 12 (continued)
IVJ
13 14
Stream
15 16 17
number
19 20 21 23
24
Description
Component
Nitrogen
Oxygen
Carbon dioxide
Water
Propylene
Propane
Ammonia
Carbon monoxide
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Sulfuric acid
Ammonium sulfate
Hydrocarbons
Organic polymers
Acrylo-
nitrile
plant Absorber
wastewater bottoms
4,470 23,714
1,000
118
1.0 118
93
79 16
Crude Crude
Water aceto- acrylo-
recycle nitrile nitrile
23,000 23,000 10,000
1,000
118
118
17.5 1.2
7
Aceto-
nitrile Light ends
column Aceto- Hydrogen column
bottoms nitrile cyanide bottoms
1,000
1,000
118 5.1
118
7.5 1.0
7.1
Product
acrylo-
nitrile
1,000
3.1
1
1
TOTALS
4,643
24,966 23,000 23,136 11,126 1,008 118
118 1,013 1,005
(continued)
-------
TABLE 12 (continued)
to
oo
Component
Nitrogen
Oxygen
Carbon dioxide
Water
Propylene
Propane
Ammonia
Carbon monoxide
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Sulfuric acid
Ammonium sulfate
Hydrocarbons
Organic polymers
25 27-
Flare
Heavy stack
ends gas
72.5
2
16
8
0.02
0.04
2
0.35
6.1
28
Fugitive
losses
0.006
0.0006
0.006
0.4
0.02
29
Incinerator
stack
gas
1,^71
174
300
435
0.034
Stream number
30 31 32
Description
Deep well Storage Product transport
pond tank loading facility
emissions losses vent
0.802
0.81 0.0065
7
TOTALS
8.1
98.9
0.43
2,680
0.81
0.0065
-------
TABLE 13. ACRYLONITRILE PLANTS l 3 'l **
Company
American Cyanamid Co.
Du Pont Co.
Du Pont Co.
Monsanto Co.
Monsanto Co.
Vistron Corp.
TOTALS
Location
New Orleans, LA
Beaumont, TX
Memphis , TN
Alvin, TX
Texas City, TX
Lima , OH
Capacity,
metric
tons/yr
91,000
160,000
130,000
200,000
190,000
91,000
862,000
Number
of
process
units
1
1
1
2
2
1
8
County
population
density,
persons/km2
1,103
98
371
29
29
104
Personal communication, T. W. Hughes of Monsanto Research Corporation and
J. Killen of Vistron Corporation. October 3, 1974.
NUMBER KEY
1 AMERICAN CYANAMID-NEW ORLEANS, LOUISIANA
2 DU PONT-BEAUMONT. TEX AS
3 DUPONT-MEMPHIS.TENNESSEE
4 MONSANTO-ALVIN. TEXAS
5 MONSANTO - TEXAS CITY. TEXAS
6 VISTRON-LIMA. OHIO
Figure 3. Locations of acrylonitrile manufacturing plants,
13Chemical Profile: Acrylonitrile. Chemical Marketing Reporter,
211(2):9, January 10, 1977.
^Statistical Abstract of the United States, 1974, 95th Edition.
U.S. Department of Commerce, Bureau of the Census, Washington,
D.C., 1974. pp. 445-461.
29
-------
located on a county line, a weighted average was used for the popu-
lation density.
The representative plant capacity based on the number of locations
is 140,000 ± 50,000 metric tons/yr, while the representative plant
capacity based on the number of processing units is 110,000 ±
20,000 metric tons/yr. The value based on plant locations (140,000
± 50,000 metric tons/yr) is used in Section V to define the repre-
sentative plant capacity.
30
-------
SECTION IV
EMISSIONS
A. SELECTED POLLUTANTS
1. Locations and Description of Emissions
The process mechanism and the formation of atmospheric emissions
were described in Section III. Based on that information, the
emission points within an acrylonitrile plant are the absorber
vent, incinerator, flare, deep well pond, storage tanks, product
transport loading facility, and fugitive emission points. Cri-
teria pollutants which are emitted include carbon monoxide,
hydrocarbons, nitrogen oxides, and sulfur oxides.3 A total of 43
chemical substances were identified as potential emissions from
acrylonitrile plants and these are presented in Table 14. This
list was compiled from two analyses of quencher wastewater;11 from
a personal communication with A. W. Busch, Regional Administrator,
Region IV, U.S. Environmental Protection Agency, February 1974;
and from atmospheric emissions identified by Schwartz et al.3 A
sampling program was performed to quantify these compounds plus
others which may not previously have been known to be present.
TABLE 14. SUSPECTED EMISSIONS FROM ACRYLONITRILE
MANUFACTURE PRIOR TO FIELD SAMPLINGS,b,3,11
Acetaldehyde
Acetaldehyde cyanohydrin
Acetic acid
Acetone
Acetone cyanohydrin
Acetonitrile
Acrolein
Acrolein cyanohydrin
Acrylonitirle
Allyl cyanide
Ammonium acetate
Ammonium acrylate
Ammonium formate
Ammonium methacrylate
Benzene
Benzonitrile
Carbon monoxide
cis-Crotonitrile
Cyanopyrazine
Ethane
Ethylene
Fumaronitrile
Furonitrile
Hydrogen cyanide
Lutidine compounds
Maleonitrile
Malononitrile
Methacrylonitrile
Methane
Methyl pyrazine
Nicotinonitrile
Nitrogen oxides
Propane
Propionitrile
Propylene
Pyrazine
Pyrazole
Succinonitrile
Sulfur dioxide
Sulfur trioxide
Ticoline
Toluene
trans-Crotonitrile
aPersonal communication, A. W. Busch, Regional Administrator,
Region IV, U.S. Environmental Protection Agency, February 1974.
''Acrylonitrile and benzene are suspected carcinogens.
31
-------
Table 15 lists the materials found in atmospheric emissions from
acrylonitrile plants together with the threshold limit values
(TLV's®) of the forms emitted,15 their primary ambient air quality
standards where applicable,16 their health effects,1 and their
atmospheric stabilities. Hydrocarbon emissions from acrylonitrile
manufacture can contribute to the formation of photochemical smog.
Figure 4 shows the products formed upon photo-oxidation of propyl-
ene,17 the hydrocarbon that is emitted in the largest quantities.
8
0.54
0.45
0.36
0.27
0.18
0.09
OZONE
0123456
ELAPSED TIME, hr
INITIAL CONDITIONS:
PROPYLENE CONCENTRATION= 0.54ppm
NITROGEN OXIDE CONCENTRATION = 0.40 ppm
Figure 4. Products of photochemical oxidation of propylene.17
2. Factors Affecting Emissions
a.
Absorber Vent Gas—
The absorber vent gas consists of reactor product which has been
cooled, neutralized, and scrubbed for nitrile recovery. Absorber
vent gas composition depends on catalyst type, reactor operating
15TLVs® Threshold Limit Values for Chemical Substances and Physi-
cal Agents in the Workroom Environment with Intended Changes
for 1975. American Conference of Governmental Industrial Hy-
gienists, Cincinnati, Ohio, 1975. 97 pp.
16Air Quality Data - 1973 Annual Statistics. EPA-450/2-74-015,
U.S. Environmental Protection Agency, Research Triangle Park,
North Carolina, November 1974. 151 pp.
17Pitts, J. N., A. C. Lloyd, and J. L. Sprung. Ecology, Energy,
and Economics Chemistry in Britain, 11;247-256, July 1975.
32
-------
TABLE 15. CHARACTERISTICS OF MEASURED EMISSIONS FROM ACRYLONITRILE MANUFACTURE
U)
Material emitted
TLV, '
Primary ambient air
quality standard,16
g/m3
Health effects1
Atmospheric stability
Carbon monoxide 0.055
Hydrocarbons (nonmethane)
Nitrogen oxides (as N02) 0.009
Sulfur oxides (as S02) 0.013
0.040
(1 hr>
0.000160* (3 hr)
0.000100 (1 yr)
0.000365 (24 hr)
Asphyxiant; combines with hemo-
globin to prevent dissociation
oE oxyhemoglobin
Toxic
Strong irritant to eyes and
mucous membranes
Stable
Contributes to photo-
chemical smog
Contributes to photo-
chemical smog
Forms sulfuric acid
and sulfates
Methane
Ethane
Ethylene
Propane
Propylene
Butene
Butanes
Acetaldehyde
Pentanes
Methanol
Hexanes
Benzene
Toluene
Acrylonitrile
Ethanol
Acetonitrile
Hydrogen cyanide
Fumaronitrile
Pyridine
Propiona Idehyde
Furan
Ammonia
Allyl alcohol
0.714
1.34
1.25
1.96
2.59
o.ie
1.8
0.260
0.360
0.03
0.375
0.045
1.90
0.070
0.011
0.015
0.018
0.005
Simple asphyxiant
Simple asphyxiant
Simple asphyxiant
Simple asphyxiant
Simple asphyxiant
Simple asphyxiant
Simple asphyxiant
Moderately toxic and narcotic
Asphyxiant
Toxic by ingestion
Moderately toxic by inhalation
Toxic by ingestion, inhalation,
skin absorption,- suspected carcinogen
TOXIC by ingestion, inhalation,
skin absorption
Toxic by inhalation and skin
absorption
Noncumulative poison
Toxic
Toxic by ingestion, inhalation,
skin absorption
Toxic by ingestion and inhalation
Toxic and irritant
Toxic by skin absorption
Toxic and irritant
Toxic by ingestion and inhalation,
strong irritant to eyes and skin
Note: Blanks indicate data not available.
aThere is no primary ambient air quality standard for hydrocarbons; the value used in this report for hydrocarbon is
a guideline for meeting the primary ambient air quality standard for oxidants.
-------
conditions, absorber temperature, reactor feed rates and feed
material composition.3
Catalyst types used in the manufacture of acrylonitrile include
Catalyst A (prior to 1967), Catalyst 21 (1967 to 1973), and
Catalyst 41 (since 1973). All plants used Catalyst 41 in 1976.
Emission factors for four plants using Catalyst 21 are presented
in Table 16 which shows the variability of emissions due to the
factors affecting emissions when using Catalyst 21. The average
emission factors for Catalyst 21 and Catalyst 41 are compared in
Table 17. This table shows the reduction in absorber vent emis-
sions, by chemical substance, caused by the change in catalyst
type. Emission factors for nitrogen indicate an increase of 21%
in rated capacity of existing plants due to the change to Catalyst
41. The calculation of this increased capacity is given in
Appendix A together with field sampling data for absorber vent
emissions.
b. Incinerator Stack Gas—
Acrylonitrile plants use an incinerator (thermal oxidizer) for the
ultimate disposal of some liquid wastes and residues. Materials
incinerated can include acetonitrile by-product, hydrogen cyanide
by-product, polymers and heavy ends from still bottoms, and
quencher wastewater. Normally, only the acetonitrile and hydrogen
cyanide are incinerated since the polymers, heavy ends, and waste-
water are disposed of in deep wells. During deep well injection
pump failure, which occurs on the average of once a year, these
wastes are also incinerated.3
The amounts of acetonitrile and hydrogen cyanide by-products
incinerated are determined by their market demand. Excess by-
product formed is incinerated. Currently (1976), only one plant
(Vistron Corporation, Lima, Ohio) markets acetonitrile (personal
communication, T. W. Hughes of Monsanto Research Corporation and
J. Killen of Vistron Corporation, October 3, 1974). However,
Du Pont has announced plans to market by-product acetonitrile
which is to be recovered and refined at its Beaumont, Texas plant.
Should the market for acetonitrile expand as anticipated,
Du Font's Memphis, Tennessee plant could provide additional aceto-
nitrile.18 Each of the plants markets hydrogen cyanide. Fifty
percent of the hydrogen cyanide is sold, while 40% is incinerated
and 10% is sent to deep well disposal.3
Four plants surveyed by Houdry dispose of quencher wastewater by
steam stripping volatile organics from the water in a wastewater
column and sending the water to a deep well.3
Besides requiring more fuel, incinerating the quencher wastewater
increases atmospheric emissions. Sulfuric acid in the quencher
18Acetonitrile's Economics are Alluring to Du Pont. Chemical
Marketing Reporter, 208(16):4, October 1975.
34
-------
TABLE 16. ABSORBER VENT DISCHARGES USING CATALYST 213
Emission factor
Material emitted
Carbon dioxide
Carbon monoxide
Methane
Ethane and ethylene
Propylene
Propane
Hydrogen cyanide
Acrylonitrile
Acetonitrile
Acetaldehyde
Acetone
Acrolein
Nitrogen
Oxygen
Water
51-1
294
180
47
124
2
29
6
9,726
865
605
51-2
508
178
52
144
0.5
0.4
8
7,222
303
by plant,
51-3
450
187
1
8
50
35
6
9,133 8
856
383
g/kg
51-4
350
167
1
50
35
4
9
0.2
0.13
0.08
,774
763
787
Mean ± 95%
confidence limit
400 ± 153
178 ± 13.2
1
4
50 ± 3.3
84.5 + 91.9
- 84.5
2 ± 4
11 ± 20
7
0.2
0.13
0.08
8,714 ± 1,701
697 ± 424
592 + 1,470
- 592
Note: Blanks indicate data not available.
TABLE 17. EFFECT OF CATALYST TYPE ON ACRYLONITRILE ABSORBER VENT EMISSIONS3
Emission factor, g/kg
Component
Nitrogen
Oxygen
Carbon dioxide
Carbon monoxide
Cs-Hydrocarbons
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Catalyst 21
8,714
697
400
178
134
11
7
2
Catalyst 41
5,865
206
185
79.3
55.0
0.039
0.625
0.275
Percent reduction in
emission factor by
use of Catalyst 41
32.7
70.4
53.8
55.5
59
99.6
91.2
86.2
Catalyst 21 is no longer used by any operating plant. Purpose of the
table is to show the reduction in emissions since the catalyst change.
35
-------
water, used for neutralization of reactor effluents, forms ammoni-
um sulfate. The amount of ammonium sulfate in the wastewater,
which represents 0.093 kg/kg of acrylonitrile product, forms
0.044 kg/kg of sulfur oxides (as SO2) if incinerated.
Emission factors for the incineration of all by-product aceto-
nitrile and 40% of the hydrogen cyanide by-product are given in
Tables 18 and 19. The values in Table 18 show the plant data using
Catalyst 21 obtained by Schwartz et al.,3 while Table 19 shows the
emissions data using Catalyst 41 obtained through field sampling.
Composited field sampling results for two incinerators are shown
in Appendix B.
TABLE 18. REPORTED INCINERATOR STACK EMISSION FACTORS3
(Catalyst 21)
Material
emitted
Nitrogen
Oxygen
Carbon dioxide
Water
Nitrogen oxides
Sulfur oxides
Ammonia
Hydrogen
cyanide
Emission factor
51-1
a
~b
_b
7.3
_c
0.3
0.02
51-2
1,251
174
282
160
0.01
_C
K
0.001
by plant, g/kg
51-3
_a
_a
-
26
-"
K
51-4
2,290b
317
709
0.4
c
K
K
Mean
value,
g/kg
1,771
174
300
435
2.6
6. 5
-"
0.011
Material was qualitatively identified but not quantified.
Not reported.
Values not reported but assumed to be zero.
Representative plant does not incinerate ammonia in 1976, hence,
no ammonia emission; i.e., emission factor for ammonia is zero.
TABLE 19. INCINERATOR STACK EMISSION FACTORS FROM FIELD SAMPLING
(Catalyst 41)
Material emitted
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Methane
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Emission factor, g/kg
0.0040 + 10%
0.0203 ± 50%
0.5420 ± 23%
0.0176 ± 49%
0.0023 ± 50%
<0.0015
<0.0015
0.343 + 428%
- 100%
36
-------
NOX formation in the incinerator from nitrile (-CN) combustion is
1% to 3% of theoretical based on data for a commercial incinerator
presented by Walker.19 Field sampling shows that 0.6% of the
nitrile feed to the incinerator forms nitrogen oxides, and >99% of
the nitriles combusted form carbon dioxide and nitrogen.
c. Deep Well Pond—
Acrylonitrile plants use a pond for temporary disposal of plant
wastewater. Composition of the wastewater was shown earlier
(Section III.A.2.c). This nonaerated pond is used for solids
removal from the wastewater prior to deep well injection of the
wastewater for ultimate disposal. Since the water contains vola-
tile organic materials, it is a source of atmospheric emissions of
hydrocarbons. Reduction in total hydrocarbon emissions can be
achieved by covering the pond with a high molecular weight oil.
Emission factors obtained through field sampling for controlled
and uncontrolled deep well pond emissions are presented in Table 20,
The three plants in Texas use a lube oil cover on the pond. Other
plants do not.
d. Flare Stack—
A flare is used to burn gaseous hydrocarbon streams. For acrylo-
nitrile plants, the flow rate from the flare is 98.5 g/kg which
corresponds to 1,500 kg/hr for the representative plant. Combus-
tion efficiency for flares has been reported as 90% for carbon
monoxide and 75% to 80% for hydrocarbons.20 Atmospheric emission
factors given by Schwartz et al.3 are presented in Table 21.
Feed streams to the flare stack consist of continuous vent streams
from decanters used on product purification columns (stripper,
extractive distillation, and light ends) and from intermittent
streams. The intermittent streams come from emergency use of
propylene storage tank pressure relief valves and relief valves on
the propylene preheater, and they also result during plant shut-
down for equipment purging. The total amount of flare feed during
infrequent intermittent releases to the flare is 440 g/kg with 80%
coming from the propylene preheater and 20% from plant shutdown
purges.3
19Walker, H. M. NOX Formation During Incineration of Nitrogenous
Residues. In: Clean Up of Plant Waste Streams, Conference on
the Clean Up of Plant Waste Streams, New Orleans, Louisiana,
March 12, 1973. 13 pp.
20Schwartz, W. A., et al. Engineering and Cost Study of Air Pollu-
tion Control for the Petrochemical Industry. Volume I: Carbon
Black Manufacturing by the Furnace Process. EPA-450/3-73-006-a,
U.S. Environmental Protection Agency, Research Triangle Park,
North Carolina, June 1974. 116 pp.
37
-------
TABLE 20. HYDROCARBON EMISSION FACTORS FOR
ACRYLONITRILE DEEP WELL PONDS3>b
-------
3. Emission Factors
Emission factors for uncontrolled and controlled emissions from
acrylonitrile manufacture are summarized in Tables 22 and 23 for
each emission (criteria pollutants and chemical substances) from
each emission point. In three of the six acrylonitrile plants, the
absorber vent and the deep well pond are controlled. All other
emission points are uncontrolled in acrylonitrile plants. Numbers
presented represent mean values of the emission factors and their
corresponding uncertainties. Data used to generate these tables
are taken from Appendixes A through G.
B. DEFINITION OF A REPRESENTATIVE SOURCE
In order to determine the source severity which is described in
Section IV. C, a representative source of acrylonitrile manufacture
was defined as using the SOHIO ammoxidation of propylene technol-
ogy and Catalyst 41, and as having an acrylonitrile production
capacity of 140,000 metric tons/yr. The representative source has
an absorber stack height of 62.79 m, and incinerator stack height
of 33.45 m, and a flare stack height of 62.87 m. The representa-
tive plant is located in a community with a population density of
402 persons/km2, 1 km from its nearest community neighbor.
Average wind speed at the representative plant is 4.47 m/s. Data
used to determine the representative plant are presented in Table 24
C. SOURCE SEVERITY
To assess the environmental impact of atmospheric emissions from
acrylonitrile manufacture, the source severity for each material
emitted from each emission point was estimated. Source severity
is defined as the pollutant concentration to which the population
may be exposed divided by an "acceptable concentration" . The
exposure concentration is the time-averaged maximum ground level
concentration as determined by Gaussian plume dispersion methodol-
ogy. The "acceptable concentration" is that pollutant concentra-
tion at which an incipient adverse health effect is assumed to
occur. For criteria pollutants, it is the corresponding primary
ambient air quality standard. For noncriteria pollutants/ it is a
surrogate air quality standard as determined by reducing TLV's for
chemical substances using an appropriate safety factor. The
source severity, S, is:
(3J
Xmax is the time-averaged maximum ground level concentration of
each material emitted from a representative plant. F is defined
as a primary ambient air quality standard for criteria pollutants
(particulate, SOX, NOX, CO, and hydrocarbons) , while for non-
criteria pollutants,
F = TLV • 8/24 • 0.01, g/m3 (4)
39
-------
TABLE 22.
EMISSION FACTORS FOR ACRYLONITRILE MANUFACTURE BY EMISSION POINT (UNCONTROLLED EMISSIONS)
(gAg)
Emission point Storage tank emission point
Material jutted
Pollutants
Carbon monoxide
Hydrocarbons (as CHU)3
Nitrogen oxides
Sulfur oxides
Particulates
Chemical substances
Methane
Ethane
Ethylene
Propane and Propylene
Butene
Benzene
Toluene
Acrylonitrile
Acetonltrile
Hydrogen cyanide
Fumaronitrile
Pyridine
Propionaldehyde
Fur an
Ammonia
Allyl alcohol
Product Two product Three product
transport acrylonitrile acrylonitrile
Absorber Incinerator Flare Deep well Fugitive loading run-down field storage
vent stack stack pond emissions facility tanks" tanks'*
79.3
57.1
0.67
1.93
2.57
55.0
0.400
0.146
0.065
0.039
0.625
0.275
0.0061
0.467
0.024
±
±
t
1
±
t
±
±
t
t
±
t
±
t
6% 0.0040 ± 10%
7% O.O203 t 47% 0.268 11 1 61% O.O0038 t 20% 0.0055 t 20% 0.039 1 2O% 0.17 1 20%
0.542 * 1O7% 0.01
- 100%
0.0176 ± 59%
6% 0.0023 ± 10%
92%
81%
60% O.022 0.000006 t 2O%
50%
50%
50%
41%
-------
TABLE 23. EMISSION FACTORS FOR ACRYLONITRILE MANUFACTURE
BY EMISSION POINT (CONTROLLED EMISSIONS)
95% for thermal oxidizers or
catalytic incinerators for the carbon monoxide and hydro-
carbon emissions from absorber vent.
Control efficiency is 92t when using a lube oil covering
on pond for control of hydrocarbons.
TABLE 24.
PLANT PARAMETERS USED IN DETERMINING THE
REPRESENTATIVE ACRYLONITRILE SOURCE
Plant parameter
Technology
Catalyst type
Capacity, metric tons/yr
Absorber stack height, m
'Incinerator stack height, m
Flare stack height, m
Population density, persons/km2
Wind speed, m/s
Value
SOHIO
41
140,000 i 50,000
62.8 t 5.8
33.5 ± 8.2
62.9 t 25.0
402
4.5
Reference
3
3
13
3
3
3
14
41
-------
The factor 8/24 adjusts the TLV for continuous rather than workday
exposure, and the factor of 0.01 accounts for the fact that the
general population is a higher risk group than healthy workers.
Thus, the source severity represents the ratio of the maximum mean
ground level exposure to the hazard level of exposure for a given
pollutant.
The maximum ground level concentration,
ing to Gaussian plume dispersion theory:
max'
"
is calculated accord-
Xmax = 2 Q
(5)
nH2eu
where Q = mass emission rate, g/s
u = average wind speed, m/s
H = effective emission height, m
e = 2.72
ii = 3.14
Equation 5 yields a value for a short-term averaging time during
which the Gaussian plume dispersion equation is valid.
The short-term averaging time was found to be 3 minutes in a
study of published data on lateral and vertical diffusion. For
a continuously emitting source, the maximum mean ground level
concentration for time intervals between 3 minutes and 24 hours
can be estimated from the relation:21
/ x o. 17
xmax xmax
(6)
where t0 = the short-term averaging time or 3 min
t = the averaging time, min
For noncriteria pollutants, the averaging time, t, is 1,440 min
(24 hr). For criteria pollutants, the averaging times are those
used in the definition of the primary ambient air quality stan-
dards. The only exception is NOX, for which the primary standard
averaging time is 1 year. Since Equation 6 is not valid for
averaging times of this magnitude, the calculation of Ymax for NOX
is based on Equation 5.13 of Reference 21 which estimates the
annual average ground level concentration.
Insertion of the average wind speed of 4.5 m/s into the above
equations leads to the severity factor equations listed in
Table 25 as calculated in Appendix H.
2turner, D. B. Workbook of Atmospheric Dispersion Estimates.
Public Health Service Publication No. 999-AP-26, U.S. Department
of Health, Education, and Welfare, Cincinnati, Ohio, 1969. 64 pp
42
-------
TABLE 25. SOURCE SEVERITY EQUATIONS
Equation in
Pollutant Source severity Equation Appendix H
Particulate
SOX
NO
Hydrocarbons
CO
All others
S =
S =
S =
S =
S =
S =
70 QH"2
50 QH~2
315 QH-2-1
162.5 QH~2
0.78 QH~2
5.5 QH~2 (TLV)-1
7
8
9
10
11
12
H-40
H-43
H-57
H-35
H-29
H-70
Q = emission rate, g/s
H = effective emission height, m
TLV = threshold limit value, g/m3
The effective emission heights used in the calculations are summar-
ized in Table 26. Stack heights shown for the absorber vent,
flare stack, and incinerators were obtained from Reference 3 and
mean values are listed in Table 24. Stack heights for the sotrage
tanks are listed in Table 11. Emission heights for the product
transport loading facility and the fugitive emissions were assumed
to be 9.1 m.
TABLE 26. EFFECTIVE EMISSION HEIGHTS USED TO CALCULATE
MAXIMUM GROUND LEVEL CONCENTRATIONS
Emission point Stack height, ma
Absorber vent 62.8
Flare stack 62.9
Incinerator 33.5
Product transport loading facility 9.1
Storage tanks 15.2
Fugitive emission 9.1
Deep well pond 9.1
aStack height values represent physical stack heights.
Visual observation during sampling showed plume rise
to be insignificant.
The emission rates (Q) were obtained from the emission factors in
Table 22. The resulting maximum ground level concentrations are
tabulated in Table 27. Source severities for uncontrolled and
controlled emissions are shown in Tables 28 and 29. In these
calculations, intermittent sources, such as fugitive emissions
and storage tank vents, were treated as continuous sources with
their respective annual emission rates. In addition, it was
assumed that Gaussian plume dispersion theory is equally valid
43
-------
TABLE 27.
MAXIMUM GROUND LEVEL CONCENTRATIONS OF ATMOSPHERIC EMISSIONS FROM ACRYLONITRILE MANUFACTURE (UNCONTROLLED EMISSIONS)
(mg/m3)
Material emitted
Criteria pollutants
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Participates
Chemical substances
Methane
Ethane
Ethylene
Propane and propylene
Butene
Benzene
Toluene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Fumaronitrile
Pyridine
Propionaldehyde
Furan
Ammonia
Allyl alcohol
Emission point Storage tank emission point
Product Two product Three product
Deep transport acrylonitrile acrylonitrile Off- Two crude
Absorber Incinerator Flare well Fugitive loading run-down field storage specification acrylonitrileg
vent stack stack pond emissions facility tanks3 tanks acrylonitrile storage tanks
4.6 0.00083
3.3 0.00225 0.024 36 0.0013 0.018 0.046 0.2 0.03 0.04
0.41 0.0006
0.0037
0.039 0.00047
0.11
0.15
3.2 0.0013 0.00001
0.023
0.0085
0.0038
0.0023 0.00031 0.0020 0.0010 0.018 0.046 0.2 0.03
0.037 0.00031 0.00007
0.016 0.0071 0.021 0.04
0.015
1.3
0.0003
0.027
0.00001
0.0014
Note: Blanks indicate no emissions present.
Values shown apply to each tank comprising the emission point.
-------
TABLE 28. SOURCE SEVERITIES FOR UNCONTROLLED EMISSIONS
en
Material emitted
Criteria pollutants
Carbon monoxide
Hydrocarbons0 *°
Nitrogen oxides
Sulfur oxides
Particulates
Chemical substances
Methane
Ethane
Ethylene
Propane and propylene
Butene
Benzene
Toluene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Fumaronitrile
Pyridine
Propionaldehyde
Furan
Ammonia
Allyl alcohol
Emission point
Absorber Incinerator Flare Deep well
vent stack stack ponda
0.07 0.000013
10.4 0.002 0.075 98
0.48 0.0023
0.0035
0.0058 0.000051
0.0088
0.013
0.18 0.0001
0.0010
0.03e
0.001
0.0054 0.00073 0.0054
0.055 0.00047
0.15 0.068 0.200 f
-
202
0.013
0.145
0.030
Storage tank emission point
Product
Product acrylo- acrylo- Off-speci-
transport nitrile nitrile fication Crude
Fugitive loading run-down field acrylo- acrylo-
emissions facility tanks'' storage nitrile nitrile
0.0039 0.0040 0.14 0.63 0.051 0.13
0.000001
0.0028 0.043 0.108 0.47 0.071
0.000048
0.94
0.000085
Occurs on plant property.
Values shown apply to each tank comprising the emission point.
Hydrocarbons include all organic materials except methane.
Total source severity for nonmethane organic materials will not equal the source severity for hydrocarbons. Source severities
for the organic chemicals are based on the toxicity of the chemicals. The hydrocarbon source severity is based on the toxicity
of oxidants, which are the products of the photochemical degradation of the organic chemicals.
Using a TLV of 10~6 g/m3 for suspected carcinogens, as defined by EPA, the source severity for benzene becomes 900.
Indeterminate since a TLV does not exist for this material.
Note: Blanks indicate no emissions present.
-------
TABLE 29. SOURCE SEVERITIES FOR CONTROLLED EMISSIONS
Emission point
Material emitted
Absorber vent
Deep well pond
Criteria pollutants
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Particulates
Chemical substances
Methane
Ethane
Ethylene
Propane and propylene
Butene
Butane
Methanol
Pentane
Acetaldehyde
Hexane
Ethanol
Benzene
Toluene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Propionaldehyde
Furan
Allyl alcohol
<0.0035
<0.52
<0.005
<0. 00044
<0. 00065
<0.009
<0. 00005
J
<0.015a
<0. 00005
<0. 00027
<0.048
<0.0075
<0. 00065
<0.0073
<0.0015
7.
0.
0.
0.
0.
0.
0.
0.
0.
8
0068
18
0065
097
032
015
015e
016
Note: Blanks indicate no emissions present.
Control efficiency >95% for thermal oxidizers or catalytic
incinerators for the carbon monoxide and hydrocarbon
emissions from absorber vent.
Control efficiency >92% when using a lube oil covering on
pond for control of hydrocarbons.
r
Occurs on plant property.
Using a TLV of 10~6 g/m3 for suspected carcinogens, as
defined by EPA, the source severity for benzene is <4.5.
6Using a TLV of 10~6 g/m3 for suspected carcinogens, as
defined by EPA, the source severity for benzene becomes 300,
46
-------
for all emissions, irrespective of their chemical, physical or
topological characteristics. Source severity distributions for the
absorber vent are shown in Figure 5, as is the frequency at which a
source severity is less than the indicated values.
D. INDUSTRY CONTRIBUTION TO TOTAL ATMOSPHERIC EMISSIONS
The mass emissions of criteria pollutants (particulate, SOX, NOX,
CO, and hydrocarbons) resulting from acrylonitrile production
were calculated using the emission factors from Tables 22 and 23
together with the production capacity data from Table 13. The
appropriate emission factor was multiplied by the production capac-
ity nationwide and for each state in which acrylonitrile plants are
located. The total mass emissions from all sources nationwide and
for each state have been reported.22 The percent contributions to
the total emissions resulting from acrylonitrile production were
computed using these values. The results are presented in Table 30
for nationwide emissions, and in Table 31 for individual state
emissions.
TABLE 30. NATIONWIDE EMISSIONS OF CRITERIA POLLUTANTS
FROM ACRYLONITRILE MANUFACTURE
Criteria
pollutant
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Particulates
1976
Nationwide
emissions,3 »22
106 metric tons/yr
88.130
16.580
9.269
24.350
129.500
1976
Emissions from
acrylonitrile
manufacture ,
106 metric tons/yr
0.0269
0.0249
0.00047
0.000015
0
Acrylonitrile
contribution to
national total, %
0.030
0.150
0.005
0.000062
0
From all stationary sources.
E. AFFECTED POPULATION
A measure of the population which is exposed to a contaminant
concentration exceeding an acceptable level (as defined) near a
representative acrylonitrile plant can be obtained by determining
(by iteration) the values of x, the distance from the source, for
which
.. /,,\
= 1.0 (13)
22Eimutis, E. C., and R. P. Quill. Source Assessment: State-by-
State Listing of Criteria Pollutant Emissions. Contract 68-02-
1874, U.S. Environmental Protection Agency, Research Triangle
Park, North Carolina. (Final document submitted to the EPA by
Monsanto Research Corporation, June 1977.) 136 pp.
47
-------
00
I
S
I
8
I
8
ACRYLONITRILE
METHANE
PROPIONALDEHYDE
FURAN
HYDROCARBONS
b'.oooi
TOLUENE
o'.ooi
ETHANE )
ETHYLENE
ALLYL ALCOHC
BEN
L /
ZENE '
0.010
\CARBON . ^
\ MONOXIDE \
ACETONITRILE
"- PROPANE AND PROPYLENE
"'HYDROGEN CYAN IDE
o'.ioo i-ooo
SOURCE SEVERITY
10.000
Figure 5. Source severity distributions for uncontrolled
emissions in absorber vent gas.
-------
TABLE 31. EMISSIONS OF CRITERIA POLLUTANTS FROM
ACRYLONITRILE MANUFACTURE BY STATE
vo
Criteria
pollutant
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Particulates
Total state
emissions,3 »22
State 10 6 metric tons/yr
Louisiana
Ohiob .
Tennessee
Texas0
Louisiana
Ohiob .
Tennessee
Texas0
Louisiana
Ohiob .
Tennessee
Texasb
Louisiana
Ohiob b
Tennessee
Texasb
. . b
Louisiana
Ohiob .
Tennessee
Texas0
0.746
14.370
0.223
1.913
1.009
0.839
0.258
2.158
0.272
0.684
0.290
0.786
0.323
2.081
0.882
0.938
1.698
3.157
1.763
9.279
Emissions from
acrylonitrile
manufacture,
10 6 metric tons/yr
0.0072
0.0072
0.0103
0.0022
0.0065
0.0065
0.0092
0.0027
0.00005
0.00005
0.00007
0.00030
0.000002
0.000002
0.000002
0.000009
0
0
0
0
Acrylonitrile
contribution
to state total, %
0.965
0.050
4.62
0.115
0.644
0.775
3.57
0.124
0.018
0.0073
0.0241
0.0382
0.0006
0.00009
0.00023
0.0096
0
0
0
0
For all stationary sources.
Uncontrolled emissions.
CAbsorber vent emissions controlled by 95% and deep well emissions controlled by 92%;
other emissions uncontrolled.
-------
The value of x(*)» the ground level concentration, is computed
from the equation : 2 1
x(x) =
ozux
where Q = emission rate, g/s
H = effective emission height, m
x = downwind distance from source, m
u = average wind speed (= 4.5 m/s)
a = vertical dispersion coefficient, m
z
For atmospheric stability class C (neutral conditions), oz is
given by:
o = 0.113 x°-911 (15)
z
The affected area is then computed as
A = Tr(x22 - Xl2), km2 (16)
where xj and xz are the two roots of Equation 13.
The mean population density, Dp, is calculated as follows:
n
£°p.
D = -, persons/km2 (17)
where Dp = county population density for plant i
n = number of plants
The product A • Dp is designated the "affected population," which
was computed for each compound and each source for which the
source severity, S, exceeds 1.0. The results are presented in
Table 32. In Table 32, dashes indicate that the material shown
is not discharged from the emission point listed; hence, there
is no possibility for an affected population. Zeros indicate
that material is discharged from the emission point but that the
resulting ambient levels have source severities £1.0. The equiva-
lent plant population for the representative plant is 1,600 persons
when applying the average county population density (402 persons/
km2) to the plant area (4 km2). Any affected population 11,600
23Eimutis, E. C., and M. G. Konicek. Derivations of Continuous
Functions for the Lateral and Vertical Atmospheric Dispersion
Coefficients. Atmospheric Environment, 6:859-863, November 1972.
50
-------
TABLE 32. AFFECTED POPULATION*
Component
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Methane
Absorber
0
13,300
-
-
0
Incinerator
0
0
0
0
0
Flare
stack
_
0
0
-
-
Deep
well
pond
^
1,590
-
-
-
Product
transport
Fugitive loading
emissions facility
^m ^
0
- -
- -
- -
Storage
tanksb
^
-
—
-
-
Ethane 0
Ethylene 0
Propane and propylene 0
Butene 0
Butanes
Pentanes
Hexanes
Jf] Benzene 0
Toluene 0
Acrylonitrile 0
Acetonitrile 0
Hydrogen cyanide 0
Fumaronitrile
Pyridine
Propionaldehyde 0
Furan 0
Ammonia -
Allyl alcohol 0
Acetaldehyde 0
Methanol 0
Ethanol 0
0
0
0
0
0
0
0
0
156
0
0
0
0
Dashes indicate that material shown is not discharged from emission point listed; zeros
indicate that ambient levels resulting from discharged material produce source severi-
ties < 1.0.
Value shown is largest value for all storage tanks.
-------
indicates that the exposure occurs on the plant site and not on
the surrounding community. The total number of persons affected
by a representative plant is 13,300. This affected population
represents the number of persons exposed to nonmethane hydro-
carbon emissions which exceed the primary ambient air quality
standard (guideline) for hydrocarbons (160 x 10~6 g/m3); 96% of
the total hydrocarbons emission is due to propane and propylene
emissions. No nonplant persons are exposed to source severities
>1.0 nitrile emissions.
F. TRENDS IN ACRYLONITRILE PLANT EMISSIONS
In 1973, 613,700 metric tons of acrylonitrile were produced. As
discussed in Section VI, a total of 1.3 x 106 metric tons of
acrylonitrile is expected to be produced in 1978.2 This corre-
sponds to an overall increase in acrylonitrile manufacture of 112%
for the 5-year period 1973 to 1978. Atmospheric emissions from
the acrylonitrile absorber vent will follow the trends presented
in Table 33 and Figure 6 based on anticipated production and
emission factors.
TABLE 33. ANNUAL EMISSIONS OF CRITERIA POLLUTANTS
FROM ACRYLONITRILE PLANTS
Year
Carbon monoxide,
103 metric tons
Total hydrocarbons,
103 metric tons
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
54^
82a
93a
84a
79?
80b
84C
87$
97 H
26.9d'e
30.8d'e
35.0d'e
40.45'6
48.5d'e
47a
72a
81a -
73a
69a
69b
73S
76d
85 H
24.9^>e
28. ej'6
32.3°'e
37-5n'f
44.9d,e
aAll capacity based on use of Catalyst 21.
33% Capacity based on Catalyst 41, balance
on Catalyst 21.
C66% Capacity based on Catalyst 41, balance
on Catalyst 21.
dAll capacity based on Catalyst 41.
e95% Control of carbon monoxide and hydro-
carbon emissions from absorber vent for
plants in Texas.
52
-------
200
_ ^o
>,
•S
s KB
o
en
S 50
UNCONTROLLED EMISSIONS
CATALYST21 TRANSITION CATALYST 41
CONTROLS IN TEX AS
CARBON MONOXIDE
1965
1970
1975
1980
YEAR
Figure 6.
Annual yearly mass of emission of criteria
pollutants from acrylonitrile manufacture.
The emission rate trends are not shown for sulfur oxides and
nitrogen oxides since these emissions each represent less than
1,000 metric tons per year as shown in Table 30. However, dur-
ing this period, all plants operating in Texas will be required
to install emissions control equipment which will result in
reductions in carbon monoxide and hydrocarbon emissions. Con-
trol efficiencies for both carbon monoxide and hydrocarbons have
been demonstrated to be greater than 95% through field sampling.
Therefore, the mass of emissions from acrylonitrile plants will
decrease 58% for carbon monoxide and 56% for hydrocarbons over
the period 1973 to 1978. This is due to the implementation of air
pollution control equipment on these plants as required by state
regulatory agencies.
53
-------
SECTION V
CONTROL TECHNOLOGY
A.
STATE OF THE ART
As of January 1, 1976, only Monsanto Company's plant in Alvin,
Texas was using any form of air pollution control for absorber
vent emissions. Du Font's plant located in Beaumont, Texas will
be bringing absorber vent emissions control equipment on stream
in 1976. Both of these plants are using combustion devices to
reduce emissions of carbon monoxide and hydrocarbons to levels
permitted by the Texas Air Control Board. Monsanto's control
device is a thermal oxidizer while Du Font's device will be a
catalytic oxidizer.
Monsanto uses a thermal oxidizer for by-product hydrogen cyanide
and acetonitrile disposal as well as the air pollution control
device for absorber vent gas. The unit is a thermal oxidizer
used solely for the incineration of combustibles without waste
heat recovery or steam generation. Figure 7 is a schematic flow
diagram for the unit.
HYDROGEN CYANIDE-
ACETONITRILE-
COMBUSTION AIR-
ABSORBER VENT GAS-
NATURALGAS-
\
870 °C
i i i i i I I
Figure 7. Schematic diagram for a combination byproduct
incinerator/absorber vent gas thermal oxidizer
system.
54
-------
The thermal oxidizer operates at 870°C and obtains >95% removal
of carbon monoxide and >95% combustion of total hydrocarbons.
Based on hydrocarbon content of absorber vent gas and assuming
100% combustion of liquid organics and natural gas fuel, a reduc-
tion in absorber vent hydrocarbons of >95% is obtained.
B. FUTURE CONSIDERATIONS
Since hydrocarbon emissions result from incomplete conversion in
the reactor, the acrylonitrile industry has thus far concentrated
its efforts for reducing emissions on the development of more
selective catalysts. Such catalysts would increase acrylonitrile
production while lowering the amount of by-products which are
vented. These efforts have been initiated because of escalating
propylene costs and tighter propylene supplies.3
As a result of the current concern for environmental quality,
various other methods of emission control have been suggested.
The devices recommended by Schwartz, et al,3 fall into the cate-
gory of combustion devices. These include CO-boilers, thermal
incinerators, catalytic incineration, and plume burners.3
1. Waste-Heat Recovery Boilers
Waste-heat recovery boilers are among the more efficient methods
of reducing hydrocarbons and carbon monoxide emissions, as evi-
denced by their extensive use in petroleum refineries. However,
by-product steam credit may not offset their operating cost for
use in acrylonitrile plants. Currently, sufficient quantities of
steam are provided by reactor cooling coils and waste heat recovery
from the reactor effluent. This steam is used to drive the air
blower and provide process steam requirements. Therefore, most,
if not all, of the steam produced would have to be exported. Con-
sidering the current trend toward ever higher fuel prices, exporting
steam from emission control devices may be feasible in the future.
However, it may not be economical to export steam at today's fuel
prices. Transportation costs for generated steam export may not
be a limiting factor since all acrylonitrile plants are located
near either petroleum refineries or large petrochemical complexes,
both of which are large consumers of steam.3
Table 34 presents a typical material balance for a CO-boiler
designed to process the absorber vent gas. Figure 8 is a sche-
matic flow diagram for a waste-heat recovery boiler. The data in
the table are based on a 980°C combustion zone temperature and 4
mole percent oxygen (dry bases) in the stack gas.3
No existing acrylonitrile plant in the U.S. employs waste-heat
recovery boilers on this vent stream (January 1, 1976). Therefore,
it is difficult to accurately predict equipment performance in this
application. Based upon applications in other areas, the following
potential problems exist with off-gas burning in waste-heat recovery
boilers.3
55
-------
TABLE 34. TYPICAL MATERIAL BALANCE FOR A CO-BOILER EMISSION CONTROL SYSTEM3
(kg/hr)
Component
Carbon dioxide
Carbon monoxide
Methane
Ethane
Propylene
Propane
Hydrogen cyanide
Acrylonitrile
Acetonitrile
Nitrogen
Oxygen
Water
Nitrogen oxides
Total kg/hr
Total standard m3/s
Process Combustion Natural
vent gas air gas
5,067
2,026
1,130
249
887
1,585
14
112
43
93,919 53,939 117
7,105 16,379
6,437 932
117,195 71,250 1,496
27.5
Flue
gas
20,006
147,973
7,639
14,199
124
189,941
44.5
COMBUSTION AIR,27 °C
NATURAL GAS
(SUPPLEMENTAL FUEL)
PROCESS VENT GAS, 43 °C
FLUE GAS, 399°C
BOILER FEED WATER 44,680 kg/hr, 116°C
-STEAM@3,200kPa,399°C
42,550 kg/hr (TOTAL)
36,470 kg/hr (NET)
- SLOWDOWN 2,130 kg/hr. 238 °C
Figure 8. Typical flow diagram for a CO-boiler
emission control system.3
56
-------
• Vent gas is available only at low pressure.
• Investment for required blowers, large diameter pipes
and valves, burning equipment, control systems, and
steam utilization systems is high.
• Because the gas has a low heating value (1.3 to 1.9 MJ/m3)
due to a high (95%) noncombustibles content, 30% to 35%
of the total heat requirement must be added as supple-
mental fuel to achieve complete combustion.
2. Thermal Incinerators
Figure 9 presents a schematic flow diagram for a thermal incin-
erator. Table 35 presents a material balance for this type of
control device. Data in this table are based on the same combus-
tion zone operating conditions used for the CO-boiler. Heat
generated from burning the process vent gas plus feed effluent
heat exchange is sufficient to obtain the desired operating tem-
perature. Burning of off-gas in a conventional thermal inciner-
ator results in burning and combustion efficiency problems
similar to those anticipated for a CO-boiler.3
3. Catalytic Incineration
A conventional catalytic incinerator could reduce pollutants to
levels similar to those obtained with a thermal unit. The cataly-
tic incinerator would operate at lower temperature (480°C to
650°C) and therefore would produce less NO .3
1
STACK G AS, 1,590 C
/ \
NATURAL GAS (PILOTS) -
LIQUID HYDROCARBONS, 25°C-
1.590C
-COMBUSTION AIR,25 C
Figure 9. Thermal incinerator for an acrylonitrile plant.3
57
-------
(Jl
00
TABLE 35. TYPICAL MATERIAL BALANCE FOR A THERMAL
INCINERATOR FOR BY-PRODUCT STREAMS3
(kg/hr)
Liquid hydrocarbons
Component
Hydrogen cyanide
Acrylonitrile
Acetonitrile
Sulfuric acid
Organic polymers
Carbon dioxide
Nitrogen
Oxygen
Water
Nitrogen oxides
Total kg/hr
Total m3/min
Total standard m3/s
Hydro-
cyanic
acid
953
5
0
1
0
0
0
0
3
0
962
1.4
0
Aceto-
nitrile
0
0
1,090
0
0
0
0
0
0
0
1,090
1.42
0
Heavy
ends
0
0
23
0
68
0
0
0
0
0
91
0.09
0
Combustion
air
0
0
0
0
0
0
16,564
5,029
285
0
21,878
0
1,129
Stack
gas
0
0
0
1
0
4,152
17,420
958
1,433
57
24,021
0
1,225
-------
SECTION VI
GROWTH AND NATURE OF THE INDUSTRY
A.
PROCESS TECHNOLOGY
Acrylonitrile can be produced on a commercial scale using any of
the following feedstocks: ethylene oxide, acetylene and propyl-
ene (using either nitric oxide or ammonia). Figure 10 shows the
extent of use of the various feedstock types. As shown, the
ammoxidation of propylene was the only process in use in 1975.
The use of various feedstocks has been the result of process
improvements and economics. A brief description of each tech-
nology type is given below.2
ETHYLENE OX IDE
ACETYLENE
PROPYLENE
TOTAL FOR YEARS
WHEN TWO OR
MORE FEEDSTOCKS
WERE USED
ACETYLENE USE DISCONTINUED
ETHYLENE OXIDE USE DISCONTINUED
1950
1960
1970
1980
YEAR
Figure 10. Acrylonitrile industry growth.2
59
-------
1. Ethylene Oxide Process
Acrylonitrile was first produced by the catalytic dehydration of
ethylene cyanohydrin derived from ethylene oxide and hydrogen
cyanide. The chemical reactions used for this process are:2
? ? H H
II II
H —C - C —H + HCN -HOC— C — CN (18)
\ / II
0 H H
ethylene hydrogen ethylene
oxide cyanide cyanohydrin
H H H H
II \ /
HOC—C —CN C= C + H20 (19)
H H Catalyst / \CN
ethylene acrylonitrile water
cyanohydrin
American Cyanamid Company (Warners, New Jersey) and Union Carbide
Corporation (Institute, West Virginia) have produced acrylonitrile
using this technology. However, the ethylene oxide process is no
longer used; American Cyanamid and Union Carbide shut down opera-
tions in 1956 and 1966, respectively.2
2. Acetylene Process
The following catalytic reaction of acetylene and hydrogen cyanide
over a cuprous chloride catalyst has been used to produce acrylo-
nitrile: lf2
H H
\ /
H —C^C —H + HCN - C = C (20)
Catalyst / \N
acetylene hydrogen acrylonitrile
cyanide
Three companies that have utilized the above technology (from 1953
to 1970) are Du Pont, American Cyanamid and Monsanto.2
3. Propylene and Nitric Oxide Process
The Explosives Department of Du Pont has produced acrylonitrile
by the catalytic reaction of propylene with nitric oxide:
60
-------
H H
\ /
2 C=C
H CH3
3NO
H H
\ /
C = C
H CN
3H20
0.5N2 (21)
propylene nitric acrylonitrile
oxide
This process was used through mid-1966 at Du Font's Beaumont,
Texas plant.
4 . Ammoxidation of Propylene
Ammoxidation of propylene via the SOHIO process has been used
for all acrylonitrile production since 1971. The process mech-
anisms accounting for all acrylonitrile production through 1975
have been discussed in Section III. Improvements made in the
ammoxidation process are discussed here. (From References 2 and
3, and a personal communication, T. W. Hughes of Monsanto Research
Corporation and J. Killen of Vistron Corporation, October 3, 1974.)
Process refinement has resulted from catalyst improvements. Over-
all, the SOHIO process has used three types of catalyst, designated
Catalyst A, Catalyst 21, and Catalyst 41. From 1960 to 1967, a
bismuth/molybdenum catalyst (Catalyst A) was used. Yields from
this catalyst are reported to have been 0.73 kg of acrylonitrile,
0.11 kg of acetonitrile and 0.13 kg of hydrogen cyanide per kg of
propylene feed.2
From 1967 through 1973, a catalyst based on depleted uranium
(Catalyst 21) was used. Reported yields for this catalyst are
0.85 kg of acrylonitrile, 0.10 kg of acetonitrile and 0.10 kg of
hydrogen cyanide per kg of propylene.2'3
A uranium-free catalyst based on bismuth phosphomolybdate
(Catalyst 41) has been used since 1972. Yields for this catalyst
are essentially the same as those for Catalyst 21. However,
Catalyst 41 utilizes ammonia more effectively so that less ex-
cess ammonia is required. Air requirements are also lower for
Catalyst 41 than for Catalyst 21, and this increases the capacity
of existing plants by 10% to 35% at the same reactor space veloc-
ities. Table 36 shows the yields of products formed using the
various catalyst types.2'3
5. Propane Ammoxidation
Production of acrylonitrile via the ammoxidation of propane has
been developed on a pilot scale by Davy Powergas Ltd. and by
Imperial Chemical Industries Ltd. The process catalytically
reacts propane and ammonia. Catalyst reaction conditions and
yields in this process are similar to those in propylene
61
-------
TABLE 36. EFFECT OF CATALYST IMPROVEMENTS ON ACRYLONITRILE
MANUFACTURE VIA AMMOXIDATION OF PROPYLENE3
Catalyst
type
A
21
41
First
year
of use
1960
1967
1972
Reactor yields, kg/kg propylene
Acrylonitrile
0.73
0.85
0.85
Acetonitrile
0.11
0.10
0.10
Hydrogen
cyanide
0.13
0.10
0.10
Ammonium
sulfate
0.2
0.20
0.11
ammoxidation. Propane ammoxidation differs from propylene ammoxi-
dation in the type of catalysts employed and the use of a propane
recovery and recycle system.2
The relative cost and availability of propane versus propylene
will be the determining factors in deciding on which feedstock to
use in the future. Companies producing acrylonitrile believe that
the propane-based process is too expensive (due to utility costs
for propane recycle) compared to the propylene ammoxidation pro-
cess to be widely used for acrylonitrile production.2
B. MARKETING STRENGTHS AND WEAKNESSES
Chief uses for acrylonitrile are in the production of acrylic
fibers and plastics. A flow diagram showing the uses of acrylo-
nitrile is presented in Figure 11. The demand for acrylic fibers
and plastics continues to grow with no sign of easing. In 1973,
acrylic fiber production was 3.36 x 105 metric tons, up 19% from
1972 (indicating a decline in reserves), and thus required
3.7 x 105 metric tons of acrylonitrile or about 60% of all acrylo-
nitrile production. Acrylic fibers should continue to grow at
about 7%/yr through the next 5 years.24"26
Demand for acrylonitrile-based plastics [notably acrylonitrile-
butadiene-styrene (ABS) and styrene-acrylonitrile (SAN) resins]
is growing faster than production capacity. The 1973 production
of ABS and SAN resins was approximately 4.53 x 105 metric tons,
requiring about 1.36 x 105 metric tons of acrylonitrile. The
4-year (ending in 1973) growth rate has been about 15%/yr.
21*Stobaugh, R. B. , et al. Acrylonitrile - How, Where, Who, Future,
Hydrocarbon Processing, 50:109-120, January 1971.
25Acrylonitrile (SOHIO Process). Hydrocarbon Processing, 52:99,
November 1973.
26Chemical Profile: Acrylonitrile. Chemical Marketing Reporter,
205(50):9, May 1974.
62
-------
ACRYLONITRILE-
BY - PRODUCTS•
OJ
NITRILE RUBBER
SAN RESINS
ABS RESINS
BARRIER RES INS
CYANOETHYLATED COTTON
FATTY AMINES
ACRYLIC
MODACYRLIC
ADHESIVES
DYES
PHOTOGRAPHIC EMULSIONS
INTERNAL PLASTIC IZER
D NYLON
ACETONITRILE
HYDROGEN CYANIDE
FLOCCULANT
AGENT
FLAVOR ENHANCER
i_
VITAMIN B
PERFUMES
SOLVENT
BARIUM CYANIDE
wSSm£==* CYANOGEN — CYANOPYRID.NE
AMINOPOLYCARBOXYLIC ACIDS —«-CHELATING AGENTS
SODIUM CYANIDE
_T"
-i*
ilSONICOTINICHYDRAZIDE
ISONICOTINIC ACID. ESTER. AMIDE
- PYRIDYLCARBINOL
ETHYLENEDIAMINETETRAACmCACID
ADIPONITRILE -HEXAMETHYLENEDIAMINE •
-CHELATING AGENT
•-NYLON 66
CYANOACETIC ACID-
CYANOGEN CHLORIDE
•ORGANIC SYNTHESIS
CYANURIC CHLORIDE
SODIUM FERROCYANIDE —
GUANIDINES
SUBSTITUTED CYANIMIDES
• MELAMINE
DYESTUFFS
ACETONE CYANOHYDRIN
TERT - ALKYL AMINES
ETHYLENE CYANOHYDRIN •
FUMIGANT
—-METHACRYLATE ESTERS
•ACRYLIC ESTERS
Figure 11. Acrylonitrile markets.2
-------
Combined consumption of ABS and SAN in 1973 was 4.77 x 105 metric
tons, indicating a drop in inventories. Shortage of both styrene
and butadiene may limit the growth in this area for the next few
years.
Development of barrier resins by Monsanto, Du Pont, and Vistron
for plastic soft drink bottles should also increase the demand
for acrylonitrile in the plastics industry.24"26 Demand in this
new marketing outlet for acrylonitrile is so great that new plant
expansions and construction have been completed. Monsanto Company
is expanding its new Cycle-Safe® polymer unit at Springfield,
Massachusetts and a new bottle fabrication plant at South Windsor,
Connecticut. In addition, Monsanto has begun production at three
new bottle plants.27 Vistron has built a $9 million plant to
produce its barrier resin, Barex 210.2G
Other end-uses for acrylonitrile are seen to grow more slowly
than acrylic fibers and plastics. Nitrile rubber, used in hoses,
seals, and gaskets, should show a more limited growth (5%/yr),
and will decline from its present 5% of total acrylonitrile con-
sumption .
Use of acrylonitrile in nylon production (from acrylonitrile via
adiponitrile) remains fairly limited in acceptance. Export of
acrylonitrile should remain constant at less than 4.5 x 101* metric
ton/yr. Export could decline, however, if foreign propylene
prices drop below domestic prices.2^-26
With the increasing demand for acrylonitrile products, the demand
for acrylonitrile itself should increase through 1978. The 1978
demand is predicted to be 9.99 x 10s metric tons, compared to the
1974 demand of 6.17 x 105 metric tons and 6.81 x 105 metric tons
in 1975. The historical (1963-1973) growth rate of acrylonitrile
has been 11.5%/yr; however, this should decrease slightly to ^10%/yr
through 1978.25 TO meet the increasing demand for acrylonitrile,
industry had several capacity expansions come on stream in 1976
which increased the total industry production capability to
9.31 x 105 metric tons/yr in 1977.25,26 Production capability
will, however, still fall short of demand.
The major weakness of the acrylonitrile market is the total de-
pendence of the SOHIO process on propylene which has recently
been in tight supply. Propylene is a by-product of refinery
cracking and a co-product in ethylene manufacture. Producers
can affect the supply by favoring either gasoline production or
ethylene production at the expense of propylene production, or
vice versa. The availability of refinery propylene is also
27Monsanto is Bullish on Acrylo. Chemical Week, 114(25):33,
June 1974.
64
-------
decreasing because of the use of hydro-crackers (with lower olefin
yields) and zeolite catalysts in petroleum catalytic crackers
(with lower propane/propylene yields). Refinery production of
propylene will probably not increase with expanded refinery capac-
ities. These effects will increase the price of propylene to the
chemical user. Propylene production in ethylene plants is limited
because of tight supply of raw materials, primarily naphtha (valu-
able in gasoline production) and propane. Competing with acrylo-
nitrile for the limited supply of propylene are isopropanol,
propylene oxide, polypropylene and cumene - all fast-growing
products.2t-26
European conditions, however, are different. The lower demand
for gasoline and less catcracking capacity result in a higher
supply of naphtha. European ethylene plants operate on naphtha
and produce relatively large volumes of propylene. The future
of domestic acrylonitrile production is thus closely tied in
with the European propylene situation.21*
65
-------
REFERENCES
1. Hawley, G. G. The Condensed Chemical Dictionary, Eighth
Edition. Van Nostrand Reinhold Company, New York, New York,
1971. p. 15.
2. Kirk-Othmer Encyclopedia of Chemical Technology, Second
Edition, Vol. 1. John Wiley & Sons, Inc., New York, New York,
1969. pp. 338-351.
3. Schwartz, W. A., F. B. Higgins, Jr., J. A. Lee, R. Newirth,
and J. W. Pervier. Engineering and Cost Study of Air Pollu-
tion Control for the Petrochemical Industry. Volume 2:
Acrylonitrile Manufacture. EPA-450/3-73-006-b, U.S. Environ-
mental Protection Agency, Research Triangle Park, North
Carolina. February 1975. 103 pp.
4. Considine, D. M. Chemical and Process Technology Encyclo-
pedia. McGraw-Hill Book Company, New York, New York, 1974.
p. 108.
5. Callahan, J. L., E. C. Milberger, and R. K. Grasselli.
Process for Preparing Olefinically Unsaturated Aldehydes
and Nitriles. U.S. Patent 3,427,343 (to The Standard Oil
Company), February 11, 1969.
6. Callahan, J. L., R. D. Presson, and A. F. Miller. Cylindri-
cal, Vertical, Fluidized Solid Reactor. Belgian Patent
700,641 (to The Standard Oil Company), December 28, 1967.
7. Callahan, J. L. Mixed Antimony Oxide - Uranium Oxide Oxi-
dation Catalyst. U.S. Patent 3,198,750 (to The Standard Oil
Company), June 27, 1967.
8. Miller, A. F., and M. L. Salehar. Process for the Recovery
of Ammonium Salts from Waste Streams in an Acrylonitrile
Plant. U.S. Patent 3,468,624 (to The Standard Oil Company),
September 23, 1969.
9. Fitzgibbons, W. 0., E. M. Schwerko, and A. H. Brainard.
Deep Well Disposal Process for Acrylonitrile Process Waste-
water. U.S. Patent 3,734,943 (to The Standard Oil Company),
May 22, 1973.
66
-------
10. Halvorson, D. 0., and S. N. Vines. Anti-Foulant in Acrylo-
nitrile Manufacture. U.S. Patent 3,691,226 (to E. I. du Pont
de Nemours and Company), September 12, 1972.
11. Train, R. E. Development Document for Interim Final Efflu-
ent Limitations and New Source Performance Standards for the
Significant Organic Products Segment of the Organic Chemi-
cals Manufacturing Point Source Category. EPA-400/1-75/045,
U.S. Environmental Protection Agency, Washington, D.C.,
November 1975. 391 pp.
12. Air Pollution Engineering Manual, Second Edition. J. A. Dan-
ielson, ed. Publication No. AP-40, U.S. Environmental Protec-
tion Agency, Research Triangle Park, North Carolina, May 1973.
987 pp.
13. Chemical Profile: Acrylonitrile. Chemical Marketing
Reporter, 211(2):9, January 10, 1977.
14. Statistical Abstract of the United States, 1974, 95th Edition.
U.S. Department of Commerce, Bureau of the Census, Washington,
D.C., 1974. pp. 445-461.
15. TLVs® Threshold Limit Values for Chemical Substances and Phys-
ical Agents in the Workroom Environment with Intended Changes
for 1975. American Conference of Governmental Industrial
Hygienists, Cincinnati, Ohio, 1975. 97 p.
16. Air Quality Data - 1973 Annual Statistics. EPA-450/2-74-015,
U.S. Environmental Protection Agency, Research Triangle Park,
North Carolina, November 1974. 151 pp.
17. Pitts, J. N., A. C. Lloyd, and J. L. Sprung. Ecology, Energy,
and Economics Chemistry in Britain, 11:247-256, July 1975.
18. Acetonitrile's Economics are Alluring to Du Pont. Chemical
Marketing Reporter, 208(16) :4, October 1975.
19. Walker, H. M. NOX Formation During Incineration of Nitrogen-
ous Residues. In: Clean Up of Plant Waste Streams, Confer-
ence on the Clean Up of Plant Waste Streams, New Orleans,
Louisiana, March.12, 1973. 13 pp.
20. Schwartz, W. A., et al. Engineering and Cost Study of Air
Pollution Control for the Petrochemical Industry. Volume I:
Carbon Black Manufacturing by the Furnace Process. EPA-450/3-
73-006-a, U.S. Environmental Protection Agency, Research Tri-
angle Park, North Carolina, June 1974. 116 pp.
21. Turner, D. B. Workbook of Atmospheric Dispersion Estimates.
Public Health Service Publication No. 999-AP-26, U.S. Depart-
ment of Health, Education, and Welfare, Cincinnati, Ohio,
1969. 64 pp.
67
-------
22. Eimutis, E. C., and R. P. Quill. Source Assessment: State-
by-State Listing of Criteria Pollutant Emissions. Contract
68-02-1874, U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. (Final document submitted to
the EPA by Monsanto Research Corporation, June 1977.) 136 pp.
23. Eimutis, E. C., and M. G. Konicek. Derivations of Continuous
Functions for the Lateral and Vertical Atmospheric Dispersion
Coefficients. Atmospheric Environment, 6:859-863, November
1972.
24. Stobaugh, R. B., et al. Acrylonitrile - How, Where, Who,
Future. Hydrocarbon Processing, 50:109-120, January 1971.
25. Acrylonitrile (SOHIO Process). Hydrocarbon Processing, 52:99,
November 1973.
26. Chemical Profile: Acrylonitrile. Chemical Marketing
Reporter, 205(50):9, May 1974.
27. Monsanto is Bullish on Acrylo. Chemical Week, 114(25):33,
June 1974.
28. Evaporation Loss from Fixed Roof Tanks. Bulletin 2518, Ameri-
can Petroleum Institute, New York, New York, 1962. 38 pp.
29. Use of Variable Vapor Space Systems to Reduce Evaporation
Loss. Bulletin 2520, American Petroleum Institute, New York,
New York, 1964. 14 pp.
30. Petrochemical Evaporation Loss from Storage Tanks. Bulle-
tin 2523, American Petroleum Institute, New York, New York,
1969. 14 pp.
31. Evaporation Loss from Floating Roof Tanks. Bulletin 2517,
American Petroleum Institute, New York, New York, 1962. 13 pp.
32. Evaporation Loss in the Petroleum Industry - Causes and Con-
trol. Bulletin 2513, American Petroleum Institute, New York,
New York, 1959. 57 pp.
33. Martin, D. 0., and J. A. Tikvart. A General Atmospheric Dif-
fusion Model for Estimating the Effects on Air Quality of One
or More Sources. Presented at the 61st Annual Meeting of the
Air Pollution Control Association, St. Paul, Minnesota,
June 23-27, 1968. 18 pp.
34. Tadmor, J., and Y. Gur. Analytical Expressions for the Verti-
cal and Lateral Dispersion Coefficients in Atmospheric Diffu-
sion. Atmospheric Environment, 3(6) :688-689, November 1969.
68
-------
35. Gifford, F. A., Jr. An Outline of Theories of Diffusion in
the Lower Layers of the Atmosphere. In: Meteorology and
Atomic Energy 1968, Chapter 3, D. A. Slade, ed. Publication
No. TID-24190, U.S. Atomic Energy Commission Technical Inform-
ation Center, Oak Ridge, Tennessee, July 1968. p. 113.
36. Code of Federal Regulations, Title 42 - Public Health,
Chapter IV - Environmental Protection Agency, Part 410 -
National Primary and Secondary Ambient Air Quality Standards,
April 28, 1971. 16 pp.
37. Determination of Sulfur Dioxide Emissions from Stationary
Sources - Method 6. Federal Register, 36(24):24882-24891,
1971.
38. Determination of Nitrogen Oxide Emissions from Stationary
Sources - Method 7. Federal Register, 36(24):24891-24893,
1971.
39. Mienire, J. P., and M. W. Dietrich. Determination of Trace
Organics in Air and Water. Journal of Chromatographic Sci-
ence, 11(11):559-570, 1973.
40. Liethe, W. The Analysis of Air Pollutants. Ann Arbor -
Humphery Science Publications, Ann Arbor, Michigan, 1970.
p. 227. [Used as NIOSH Physical and Chemical Analysis
Measurements (P+CAM) Procedure #116]
41. Standard Methods for the Examination of Water and Wastewater,
American Public Health Association, Washington, D.C., 1971.
pp. 404-406.
42. Hanker, J. S., R. M. Gamson, and H. Klapper. Fluorometric
Method for Estimation of Cyanide. Journal of Analytical
Chemistry, 29 (6):879-871, 1957.
43. White, L. D., D. G. Taylor, P. A. Mauer, and R. E. Kupel. A
Convenient Optimized Method for the Analysis of Selected Sol-
vent Vapors in the Industrial Atmosphere. American Indus-
trial Hygiene Association Journal, 31(2) :225-232, 1970.
[Used as NIOSH Physical and Chemical Analysis Measurements
(P+CAM) Procedure #127]
44. Metric Practice Guide. ASTM Designation E-380-74, American
Society for Testing and Materials, Philadelphia, Pennsylvania,
November 1974. 34 pp.
69
-------
APPENDIX A
FIELD SAMPLING RESULTS FOR ABSORBER VENT GAS
The absorber vent emissions data on the following page can be
used to determine the decrease in nitrogen emissions, hence,
reactor air feed rate. Air feed rate, ammonia feed rate, and
propylene feed rate can be used to determine the increase in
acrylonitrile plant capacity of a fixed superficial linear veloc-
ity in the reactor.
Increase in capacity due to Catalyst 41 use can be determined by
the following equation.
Capacity Catalyst 41 _ total moles reactor feed for Catalyst 21
Capacity Catalyst 21 total moles reactor feed for Catalyst 41
(moles C3H6)2i + (moles NH3)21 + (moles air)21
(moles CsHg)^! + (moles NHs)^ + (moles
= 1 + 1.15 + 10.5
1 + 1.06 + 8.40
12.65
10.46
= 1.21 or 21% increase in capacity
Reference 3 indicates that the increase in capacity can vary from
10% to 35%.
70
-------
TABLE A-l. ABSORBER VENT EMISSION FACTORS
(UNCONTROLLED EMISSIONS)8
(g/kg of product acrylonitrile)
Material emitted
Average
Inert gases
Nitrogen
Oxygen
Carbon dioxide
Water
Criteria pollutants
Carbon monoxide
Hydrocarbons0
Chemical substances
Methane
Ethane
Ethylene
Propane and propylene
Acrylonitrile
Acetonitrile
Hydrogen cyanide
Propionaldehyde
Furan
Benzene
Toluene
Allyl alcohol
Butene
5,865
206
184.5
921.5
79.3
57.1
0.672
1.93
2.57
55.0
0.039
0.625
0.275
0.0061
0.467
0.146
0.065
0.024
0.400
S
± 6.3%b
± 6.8%
± 28%
± 93%
± 81%
± 85%
± 40%
± 49%
± 22%
± 50%
± 71%
± 71%
± 50%
± 50%
± 50%
The values presented in this table represent
a composite of the emissions data obtained
by sampling uncontrolled emissions from two
acrylonitrile plant absorber vents.
Uncertainty for average of two plants =
VUnCertalntyPlant A 2 + UncertaintyPlant B
"Hydrocarbons" include all organic materials
except methane.
71
-------
APPENDIX B
FIELD SAMPLING RESULTS FOR INCINERATOR STACK GASES
TABLE B-l.
INCINERATOR STACK GAS EMISSION FACTORS
(g/kg)
Material emitted
Value
Criteria pollutants
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Chemical substances
Methane
Acrylonitrile
Acetonitrile
Hydrogen cyanide
0.004 ± 10%
0.0203 ± 50%
0.542 ± 23%
0.0176 ± 49%
0.0023 ± 50%
<0.0015
<0.0015
0.34 + 428%
- 100%
72
-------
APPENDIX C
FIELD SAMPLING RESULTS FOR DEEP WELL POND EMISSIONS
TABLE C-l. DEEP WELL POND EMISSION FACTORS
(gAg)
Material emitted
Criteria pollutants
Hydrocarbons
Chemical substances
Fumaronitrile
Pyridine
Butanes
Pentane
Hexanes
Benzene
Toluene
Methanol
Acetaldehyde
Ethanol
Others
Plant Aa Plant
13 ± 61% 1.1 ±
0.036 -C
5.2 ± 74% -C
-C 0.06 +
-
-C 0.04 +
-
-C 0.04 +
-
-C 0.1 +
-
-C 0.02 +
-
-C 0.2 +
-
-C 0.06 +•
-
-C 0.1 +
-
7.8 ± 75% -C
Bb
117%
182%
1001
172%
100%
145%
100%
150%
100%
222%
100%
138%
100%
423%
100%
315%
100%
Uncontrolled emissions from deep well pond.
Controlled emissions using lube oil cover on pond.
Not detected at 0.5 ppm level.
Unidentified.
73
-------
APPENDIX D
REFERENCE 3 DATA FOR FLARE STACK EMISSIONS
TABLE D-l. FLARE STACK EMISSION FACTORS3
(g/kg)
Plant
Component
Total flow
Nitrogen
Oxygen
Carbon
dioxide
Water
Nitrogen
oxides
51-1
43.0
_a
_a
a
a
_b
51-2
105
78
2
14
11
_d
51-3
156
_a
_a
a
a
_b
51-4
90
67 .
D
18
5
0.01
Mean
98.5
72.5
2
16
8
0.01
Standard
deviation
46.55
7.78
_C
2.83
4.24
_C
Relative
uncertainty
74.06
69.9
_C
25.41
38.12
_C
Percent
uncer-
tainty
75
96
_C
158
476
_C
Identified by plant, but only qualitatively.
Not reported.
"Not determined.
Trace.
74
-------
APPENDIX E
STORAGE TANK EMISSION FACTOR CALCULATIONS
The procedure for calculating the atmospheric emissions from
fixed roof storage tanks is outlined in this section. Nonmetric
units are utilized because they represent the form of the data
used in the actual calculations. The equations discussed below
were developed and reported in API Bulletins.28"32
Storage tank emissions consist of breathing losses and working
losses. Breathing losses are caused by daily changes in ambient
temperature while working losses are caused by the filling and
emptying of the tanks. The calculations are performed in steps
as described below. All losses are calculated as equivalent
gasoline losses and then converted to specific petrochemical
losses.
Step 1. Calculate the equivalent gasoline breathing loss:
Ly =Tirp Dl'73 (H')0-51 (AT)0'50 FPC
2Evaporation Loss from Fixed Roof Tanks. Bulletin 2518, American
Petroleum Institute, New York, New York, 1962. 38 pp.
29Use of Variable Vapor Space Systems to Reduce Evaporation Loss.
Bulletin 2520, American Petroleum Institute, New York, New York,
1964. 14 pp.
30Petrochemical Evaporation Loss from Storage Tanks. Bulletin
2523, American Petroleum Institute, New York, New York, 1969.
14 pp.
3Evaporation Loss from Floating Roof Tanks. Bulletin 2517,
American Petroleum Institute, New York, New York, 1962. 13 pp.
3Evaporation Loss in the Petroleum Industry - Causes and Control.
Bulletin 2513, American Petroleum Institute, New York, New York,
1959. 57 pp.
75
-------
where L = equivalent gasoline breathing loss, bbl/yr
P = vapor pressure of material stored at bulk
temperature, psia
D = tank diameter, ft
H1 = tank outage, ft
AT = average ambient temperature change, °F
F = paint factor
C = diameter factor
The bulk temperature of stored material was taken to be 69°F for
all storage tanks. This temperature was obtained by adding 5°F
to the ambient temperature (64°F), as recommended in References
28-32 for tanks held at ambient temperature. The ambient tempera-
ture of 64°F was used because it is the national mean ambient
temperature.
Tank diameters were computed by assuming a height of 50 ft for
all tanks. The tank outage, i.e., freeboard, was taken as one-
half the tank height, or 25 ft.
The average ambient temperature change, AT, was taken as 20°F,
which is the national average value. The paint factor, Fp, was
assumed equal to unity or the value for white paint in good con-
dition. This factor can be as high as 14.6 for gray surfaces.
The diameter factor, C, is equal to unity for tanks 30 ft or
larger in diameter. For smaller tanks, the value is obtained
from a graph given in Reference 29, and is between 0.25 and 1.0.
Step 2. Calculate the equivalent gasoline working loss:
Fg =(lo700o)PVNKT (E'2)
where F = equivalent gasoline working loss, bbl/yr
V = tank capacity, bbl
N = number of turnovers per year
K = turnover factor = 1.0 for N 1 36
*• i on j_ M
r=-H for N > 36
Step 3. Compute total equivalent gasoline loss, L :
Lg = Ly + Fg (E-3)
76
-------
Step 4. Compute petrochemical losses:
(E-4)
where L = total petrochemical loss, bbl/yr
M = molecular weight of chemical stored
W = liquid density of chemical stored, Ib/gal
Step 5. Calculate emission factor:
L! = L(42)(W)
LI
Cap
E1
E1 =
E =
(E-5)
(E-6)
(E-7)
where LI = petrochemical loss, Ib/yr
Cap = production capacity, ton/yr
E1 = emission factor, Ib/ton
E = emission factor, g/kg
Using the above procedure and the storage tank input data shown in
Table E-l, the emissions data shown in Table E-2 were calculated.
TABLE E-l. STORAGE TANK INPUT DATA FOR AN ACRYLONITRILE PLANT
(UNCONTROLLED EMISSIONS) '
Tank identification
Input information
Product Product Off- Crude
acrylo- acrylo- specification acrylo-
nitrile nitrile acrylonitrile nitrile
Number of tanks 2 3
Production capacity, tons/yr 100,000 100,000
Ambient temperature, °F 64 64
Average temperature change, °F 19 19
Molecular weight, Ib/lb-mole 53 53
Liquid density, Ib/gal 6.76 6.76
Vapor pressure, psia 1.78 1.78
Bulk temperature, °F 69 69
Tank diameter, ft 16 40
Tank outage, ft 10 25
Paint factor 1.0 1.0
Diameter factor 0.77 1.0
Turnover factor 0.25 1.0
Number of turnovers per year 450 25
Tank volume, bbl 715 10,714
100,000
64
19
53
6.76
1.78
69
21
25
1.0
0.92
1.0
5
2,976
2
100,000
64
19
53
6.76
1.78
69
28
25
1.0
0.48
1.0
2
5,476
77
-------
TABLE E-2. STORAGE TANK EMISSIONS SUMMARY
(UNCONTROLLED EMISSIONS)
Material stored
Capacity,
gal
Losses
gal/yr Ib/yr
Emission
factor,
g/kg
Product acrylonitrile 30,000 1,350 9,100 0.046
Product acrylonitrile 30,000 1,350 9,100 0.046
Product acrylonitrile 450,000 5,950 40,200 0.2
Product acrylonitrile 450,000 5,950 40,200 0.2
Product acrylonitrile 450,000 5,950 40,200 0.2
Off-specification
acrylonitrile 125,000 870 5,800 0.03
Crude acrylonitrile 230,000 1,300 8,850 0.04
Crude acrylonitrile 230,000 1,300 8,850 0.04
78
-------
APPENDIX F
FUGITIVE EMISSION LOSS CALCULATIONS
Fugitive emission losses from a representative acrylonitrile
plant were calculated by identifying the fugitive emission points
and calculating the emissions using emission factors contained in
the Air Pollution Engineering Manual.12 The fugitive emission
points consist of pressure relief valves and mechanical pump seals,
Emission factors are: 3.5 Ib/day per valve for pressure relief
valves, and 20 lb/103 bbl of pumped liquid for mechanical seals.12
Individual emission points, materials emitted, emission rates, and
emission factors (g/kg acrylonitrile produced) are presented in
Table F-l. The basis for the information contained in the table
is the material balance presented in Section III.
TABLE F-l.
FUGITIVE EMISSION LOSSES FOR A
REPRESENTATIVE ACRYLONITRILE PLANT
Emission point
(by stream name)
Pressure relief valves
Propylene storage
Ammonia storage
Material
emitted
Propylene
Propane
Ammonia
Emission
rate,
kg/hr
0.066
0.0066
0.066
Emission
factor,
pg/kg
6
0.6
6
Pump seals
Absorber column bottoms
Crude acrylonitrile
(to storage)
Crude acrylonitrile
(to purification)
Crude acetonitrile
(to storage)
Crude acetonitrile
(to incineration)
Light ends column
bottoms
Product acrylonitrile
(to storage)
Product acrylonitrile
(to loading rack)
Acrylonitrile 0.77
Acetonitrile 0.09
Acrylonitrile 0.77
Acrylonitrile 0.77
Acetonitrile 0.09
Acetonitrile 0.09
Acrylonitrile 0.77
Acrylonitrile 0.77
Acrylonitrile 0.77
70
8
70
70
8
8
70
70
70
79
-------
APPENDIX G
PRODUCT TRANSPORT LOADING FACILITY EMISSION FACTORS
Atmospheric emissions from the product transport loading facility
were calculated using emission factors presented in the Air Pollu-
tion Engineering Manual.12 The emission factor for controlled
losses is 2 lb/103 bbl of material shipped.12 This is equivalent
to 6.5 mg/kg of product for a representative acrylonitrile plant.
(From Reference 12 and personal communication, T. W. Hughes of
Monsanto Research Corporation and W. Fitzgibbons of The Standard
Oil Company, June 23, 1975.)
80
-------
APPENDIX H
DERIVATION OF SOURCE SEVERITY EQUATIONS3
1. SUMMARY OF MAXIMUM SEVERITY EQUATIONS
The maximum severity of pollutants may be calculated using the
mass emission rate, Q, the height of the emissions, H, and the
ambient air quality standard, AAQS. The equations summarized in
Table H-l are developed in detail in this appendix.
TABLE H-l. POLLUTANT SEVERITY EQUATIONS FOR
ELEVATED SOURCES
Pollutant _ Severity equation
Particulates S = ^-°-
H2
S =
X
NO
X
Hydrocarbons S = 162 Q
H2
CO s-^Ii-S
H2
5.5 Q
Others S =
TLV • H2
2. DERIVATION OF x FOR USE WITH U.S. AVERAGE CONDITIONS
max
The most widely accepted formula for predicting downwind ground
level concentrations from a point source is:21
3This Appendix was prepared by T. R. Blackwood and E. C. Eimutis
of Monsanto Research Corporation, Dayton, Ohio.
81
-------
: * ft)H *(
where x = downwind ground level concentration at reference
coordinate x and y with emission height of H, g/m3
Q = mass emission rate, g/s
a = standard deviation of horizontal dispersion, m
o = standard deviation of vertical dispersion, m
u = wind speed, m/s
y - horizontal distance from centerline of dispersion, m
H = height of emission release, m
x = downwind emission dispersion distance from source of
emission release, m
IT = 3.1416
We assume that Xmax occurs when x»0 and y = 0. For a given sta-
bility class, standard deviations of horizontal and vertical dis-
persion have often been expressed as a function of downwind distance
by power law relationships as follows:3 3
oy = axb (H-2)
o, = cxd + f (H-3)
z
Values for a, b, c, d, and f are given in Tables H-231* and H-3.
Substituting these general equations into Equation H-l yields:
acirux + airufx
H- 1
2(cxd + f)2J
(H-4)
Assuming that xmax occurs at x<100 m and the stability class is
C, then f = 0 and Equation H-4 becomes:
X =
acirux
33Martin, D. 0., and J. A. Tikvart. A General Atmospheric Dif-
fusion Model for Estimating the Effects on Air Quality of One
or More Sources. Presented at the 61st Annual Meeting of the
Air Pollution Control Association, St. Paul, Minnesota,
June 23-27, 1968. 18 pp.
3**Tadmor, J., and Y. Gur. Analytical Expressions for the Vertical
and Lateral Dispersion Coefficients in Atmospheric Diffusion.
Atmospheric Environment, 3 (6):688-689, November 1969.
82
-------
TABLE H-2.
VALUES OF a FOR THE
COMPUTATION OF o a'31*
Stability class
A
B
C
D
E
F
a
0.3658
0.2751
0.2089
0.1471
0.1046
0.0722
TABLE H-3.
For Equation H-2: a = ax
where x = downwind distance
b = 0.9031
VALUES OF THE CONSTANTS USED TO ESTIMATE
VERTICAL DISPERSION3'21
Stability
Usable range class Coefficient
>1,000 m
100 to 1,000 m
A
B
C
D
E
F
A
B
C
D
E
F
Cl
0.00024
0.055
0.113
1.26
6.73
18.05
C2
0.0015
0.028
0.113
0.222
0.211
0.086
di
2.094
1.098
0.911
0.516
0.305
0.18
d2
1.941
1.149
0.911
0.725
0.678
0.74
fl
9.6
2.0
0.0
-13
-34
-48.6
f2
9.27
3.3
0.0
-1.7
-1.3
-0.35
<100 m
A
B
C
D
E
F
0.192
0.156
0.116
0.079
0.063
0.053
0.936
0.922
0.905
0.881
0.871
0.814
0
0
0
0
0
0
3For Equation H-3:
°» =
cxd + f
83
-------
For convenience, let:
AR = s and BR =
so that Equation H-5 reduces to:
X - V-<«> exp|-^]
Taking the first derivative of Equation H-6
+ exp[BRx-2d] (-b-d^-b-'*-1
(H-7)
and setting this equal to zero (to determine the roots which give
the minimum and maximum conditions of x with respect to x) yields:
= 0 = ARx-b-d-l Uxp[BRx-2d]Y-2dBRx~2d _b-dj (H-8)
Since we define that x ^ 0 or °° at xmax' ^ne f°ll°win9 expression
must be equal to 0:
-2dBRx~2d -d-b = 0 (H-9)
or
(b+d)x2d = -2dBD (H-10)
£\
or
X2d = ~-^ = 2d"2 (H-ll)
b+d 2c2(b+d)
or
X2d = d
c2(b+d)
Hence
d H2
x = at Xmax
max
Thus Equation H-2 and H-3 (at f = 0) become:
84
-------
°y - al d "2 1 (H-14)
y \c2 (d+b)
(H-15)
The maximum will be determined for U.S. average conditions of
stability. According to Gifford,35 this is when ov = o,. Since
b = 0.9031, and upon inspection of Table H-23*4 under U.S. average
conditions, oy = oz, it can be seen that 0.881 < d < 0.905 (class
C stability3). Thus, it can be assumed that b is nearly equal to
d in Equations H-14 and H-15 or:
o_ = — (H-16)
z /2
and
ov = - (H-17)
y c/2
Under U.S. average conditions, o = oz and a = c if b = d and
f = 0 (between class C and D, but closer to belonging in class C).
Then
oy = J (H-18,
Substituting for ay from Equation H-18 and for az from Equation
H-16 into Equation H-l and letting y = 0:
The values given in Table H-3 are mean values for stability class.
Class C stability describes these coefficients and exponents, only
within about a factor of two.
35Gifford, F. A., Jr. An Outline of Theories of Diffusion in the
Lower Layers of the Atmosphere. In: Meteorology and Atomic
Energy 1968, Chapter 3, D. A. Slade, ed. Publication No. TID-
24190, U.S. Atomic Energy Commission Technical Information Center,
Oak Ridge, Tennessee, July 1968. p. 113.
85
-------
or
9 n
(H-20)
3. DEVELOPMENT OF SOURCE SEVERITY EQUATIONS
Source severity, S, has been defined as follows:
_ _ xmax , _ _ xmax .„
S ~ AAQS and S F~ (H"
where X-.-,, = time-averaged maximum ground level concentration
max
AAQS = ambient air quality standard
F = TLV • 8/24 • 1/100
Values of x^.,, are found from the following equation:
IIicLX
0.17
where to is the "instantaneous" (i.e., 3-minute) averaging time
and t is the averaging time used for the ambient air quality
standard as shown in Table H-4.
a. CO Severity
The primary standard for CO is reported for a 1-hr averaging time.
Therefore,
t = 60 min
to = 3 min
|.17
xmax xmax 'cn
/ 3\0-17
\60)
ireuH2
2 Q
(3.14) (2.72) (4.5)H2
0.052 Q
(H-24)
(0.6) (H-25)
(0.6) (H-26)
H2
86
-------
TABLE H-4. SUMMARY OF NATIONAL AMBIENT AIR QUALITY STANDARDS36
Pollutant
Particulate
Sulfur oxides
Carbon monoxide
Nitrogen dioxide
Photochemical oxidants
Hydrocarbons (nonme thane)
Averaging time,
hr
Annual
(geometric mean)
24b
Annual
(arithmetic mean)
24^
b
3
b
8°
b
1
Annual
(arithmetic mean)
lb
3
(6 a.m. to 9 a.m.)
Primary
standards,
yg/m3(ppm)
75
260
80
(0.03)
365
(0.14)
None
10,000
(9)
40,000
(35)
100
(0.05)
160
(0.08)
160d
(0.24)
Secondary
standards ,
yg/m3
603
150
60
(0.02)
260C
(0.1)
1,300
(0.5)
None
(Same as primary)
(Same as primary)
(Same as primary)
(Same as primary)
The secondary annual standard (60 yg/m3) is a guide for assessing
implementation plants to achieve the 24-hr secondary standard.
Not to be exceeded more than once per year.
The secondary annual standard (260 yg/m3) is a guide for assessing
implementation plans to achieve the annual standard.
Recommended guideline.
_ 3.12 x 10~2 Q
(H-27)
Substituting the primary standard for CO (0.04 g/m3) into the
equation for S then gives:
S =
(max _ 3.12 x 10"2 Q
AAQS 0.04 H2
(H-28)
36Code of Federal Regulations, Title 42 - Public Health, Chapter
IV - Environmental Protection Agency, Part 410 - National Primary
and Secondary Ambient Air Quality Standards, April 28, 1971. 16 pp,
87
-------
or
= 0.78 Q
5CO u2 (H-29)
n
b. Hydrocarbon Severity
For nonmethane hydrocarbons, a 3-hr averaging time is used.
t = 180 min
W = Xmax InmJ (H-30)
= 0.5 Xmax (H-31)
= (0.5)(0.052) Q (H-32)
H2
- 0.026 Q fH-331
xmax H2 (H-33)
For nonmethane hydrocarbons, the concentration of 1.6 x 10"1* g/m3
has been issued as a guide for achieving oxidant standards.
Therefore
S = = - 0.026 Q _ (H_34)
AAQS 1.6 x 10'11 H2
or
162.5 Q
= .
bHC R2 (H-35)
c. Particulate Severity
The primary standard for particulate is reported for a 24-hr
averaging time.
_3__\0.17
1.440/
xmax xmax ' 1 **" ' (H-36)
H2
- = 0.0182 Q
xmax 2
88
-------
For particulates, AAQS = 2.6 x lO"*4 g/m3. Therefore
= Xmax m 0.0182 Q
AAO
-------
then the distance xmax where the maximum concentration occurs is:
Vb
For Class C conditions, a = 0.113 and b = 0.911. Substituting
these values into Equation H-45 yields:
Hl.098
xmax = 0.16
Since
7.5 H1-098 (H-46)
and
u = 4.5 m/s
and letting x = xm= , Equation K-44 becomes:
lucLX
max
In Equation H-47, the factor
4 Q _ 4 Q
Therefore,
As noted above,
I/H\O
^z> \
^x-^rr* e*pi-^) I
Therefore:
90
(H-48)
x 1.911 (7.5 H1-09B)1-911
max
o, = 0.113 x°'911 (H-50)
Z
Substitution for x yields
a =0.113 (7.5 H1-1)°'911 (H-51)
a = 0.71 H (H-52)
z
-------
xmax = H2>1 exP [- I^OTTT-HJ I (H-53>
= Q (0.371) (H-54)
or
- = 3.15 x 1Q"2 Q
rtynav \rl~DD)
Aiia^t _ p i
Since the NOz standard is 1.0 x lO"1* g/m3, the N02 severity
equation is:
, 3.15 x 10-2 Q (H_56)
2 1 x IQ-1* H2'1
or
- 315
,„
(H'
f. Noncriteria Emissions
The value of )( may be derived from Xmax' an undefined "short-term"
concentration. An approximation for longer term concentration may
be made as follows:
For a 24-hr time period,
0.17
- = / 3 min \°-*7
xmax xmax\l,440 min/ *"
(H-59)
Since the source severity is defined and derived from TLV values
as follows:
(H-60)
F = (0.0033) TLV (H-61)
then the source severity, S, is defined as
91
-------
xmav (0-35)xmav
_ _ IUO.X _ lUaX (H —
F (3.33 x 1C-3) TLV
105 Xmax
S - TT.V (H-63)
TLV
If a weekly averaging period is used, then
0.17
- / 3 \o.i?
x ~ xmaxUO,080/ (H-64)
= <°-25)Xmax (H-65)
or
and
F = (2.38 x 10~3)TLV (H-67)
and the source severity, S, is
xmax (0-25)xmax
s = -JM* = - E§x - (H-68)
F (2.38 x 10~3) TLV
or
S = (H~69)
which is entirely consistent, since the TLV is being corrected for
a different exposure period.
Therefore, the severity can be derived from Xmax directly without
regard to averaging time for noncriteria emissions. Thus, combin-
ing Equations H-69 and H-20, for elevated source, gives:
S = 5'5 Q — (H-70)
TLV • H2
4. AFFECTED POPULATION CALCULATION
Another form of the plume dispersion equation is needed to calcu-
late the affected population since the population is assumed to
be distributed uniformly around the source. If the wind direc-
tions are taken to 16 points and it is assumed that the wind
92
-------
tions are taken to 16 points and it is assumed that the wind
directions within each sector are distributed randomly over a
period of a month or a season, it can be assumed that the efflu-
ent is uniformly distributed in the horizontal within the sector.
The appropriate equation for average concentration, Xi in 9/m3
is then (for 100 m < x < 1,000 m and stability class C):20
- = 2.03 Q
0 UX
z
r
(H-71)
To find the distances at which \/AAQS = 1.0, roots are determined
for the following equation:
2.03 Q
(AAQS)
keeping in mind that:
exp - 7 hr-
= 1.0
(H-72)
°z =
+ C
where a, b, and c are functions of atmospheric stability and
are assumed to be selected for stability Class C.
Since Equation H-72 is a transcendental equation, the roots are
found by an iterative technique using the computer.
For a specified emission from a typical source, x/AAQS as a
function of distance might look as follows:
The affected population is contained in the area
A = TT(X22 - X!2)
If the affected population density is D , the total affected
population, P1, is
P1 = DpA (persons)
(H-73)
(H-74)
93
-------
APPENDIX I
AFFECTED POPULATION CALCULATIONS
The affected population was calculated using the procedure out-
lined in Section 4, Appendix H. Input data and results are
shown in Table 1-1 for the absorber vent, fugitive emissions,
product transport loading, storage tanks, incinerator, flare
stack and deep well pond. In all calculations, uncontrolled
emissions were assumed. When using emissions control on the
absorber vent, the source severity is less than 1.0, hence the
affected population is zero.
94
-------
TABLE 1-1. AFFECTED POPULATION CALCULATIONS
Absorber vent (uncontrolled emissions)
Component
Carbon monoxide
Hydrocarbons
Methane
Ethane
Ethyl ene
Propane and propylene
Butene
Toluene
Acrylonitrila
Benzene
Acetonitrile
Hydrogen cyanide
Proplonaldehyde
Puran
Allyl alcohol
Hydrocarbons
Acrylonitrile
Acetonitrile
Propane and propylene
Anon la
Aerylonitrlle
Emission
rate,
Q/S
353
255
2.99
8.59
11.4
250
1.78
0.29
0.17
0.65
2.76
1.23
0.03
2. OB
0.11
0.002
0.0019
0.0001
0.00002
0.00002
0.029
Emission Hazard Hind Population Root
height, TLV, factor, speed, density, X| ,
m a/in3 g/n3 a/a oeraons/bn2 km
62. a
62. B
62.8
62. B
62.8
62.8
62. 8
62. a
62.8
62.8
62.8
62.8
62.8
62.8
62. B
9.1
9.1
9.1
9.1
9.1
9.1
NA 0.040 4.S
NA 0.00016 4.5
0.714 0.00238 4.5
1.34 0.00447 4.5
1.25 0.00418 4.S
1.96 0.00640 4.S
2.5 0.00833 4.S
0.375 0.0012S 4.5
0.045 0.00015 4.5
0.003 0.00010 4.5
0.070 0.00023 4.5
0.011 0.000037 4.5
0.003 0.000010 4.5
0.020 0.000067 4.5
0.005 0.000017 4.5
Fugitive emissions
402 0
402 0.299
402 0
402 0
402 0
402 0
402 0
402 0
402 0
402 0
402 0
402 0
402 0
402 0
402 0
Data output
Root
"2.
ton
0
3.53
0
0
0
0
0
0
0
0
0
0
0
0
0
Affected
area,
to*
0
33.0
0
0
0
0
0
0
0
0
0
0
0
0
0
Affected
population.
0
15,700
0
0
0
0
0
0
0
0
0
0
0
0
0
(uncontrolled enissions)
NA 0.000160 4.5 402 0 0
0.045 0.000150 4.5 402 0 0
0.070 0.000233 4.5 402 0 0
1.96 0.0064 4.5 402 0 0
0.018 0.00006 4.5 402 0 0
0.045 0.0001SO 4.5 402 0 0
0
0
0
0
0
0
0
0
0
0
0"
0
Storage tanks (uncontrolled emissions)
Acrylonltrile'
Aerylonitrlle.
Rcrylonitrile.
Aerylonitrlle.
Aerylonitrlle
Acrylonitrilej:
Aerylonitrile-
Aerylonitrlle
Carbon monoxide
Hydrocarbons
Nitrogen oxides
Sulfur oxides
Methane
Hydrogen cyanide
0.206
0.206
0.9
0.9
0.9
0.13
0.13
0.13
0.0179
0.056
1.4
0.0739
0.0103
0.154
15.2
15.2
15.2
IS. 2
IS. 2
15.2
15.2
15.2
33.5
33.5
33.5
33.5
33.5
33.5
0.045 0.00015
0.045 0.00015
0.045 0.00015
0.045 0.00015
0.045 0.00015
0.045 0.00015
0.045 0.00015
0.045 0.00015
Incinerator
-------
APPENDIX J
SAMPLING AND ANALYSIS METHODS USED
AT ACRYLONITRILE PLANTS
1. TEST SITE PREPARATIONS REQUIRED
Field sampling at the acrylonitrile plants did not require test
site modifications. All of the emissions of concern in these
plants are gaseous materials, i.e., S02, NOX, HCN, CO, aceto-
nitrile, acrylonitrile and C2 and C3 hydrocarbons. Therefore,
isokinetic sampling was not necessary. The velocity, pressure,
and temperature of the absorber and incinerator stacks are con-
tinuously monitored since the acrylonitrile process is designed
for 100% remote control of operations. Control room data were
employed in conjunction with the measurement of sample volume to
calculate emission factors after sampling had been completed.
The plant monitors were calibrated before the sampling program
to assure accuracy.
Stainless steel sample lines are installed at the facilities and
are accessible from a platform. The line at the absorber vent
samples gases between the absorber and the pressure control valve.
Since this line is under positive pressure (35 kPa gage) it was
purged before sampling and no pump was required during sampling.
The temperature at the absorber vent was 49°C and the line was
not heated. To prevent condensation of the water-saturated
stream it was necessary to heat this sampling line to 50°C during
the sampling with an existing steam tracing on the line. Sketches
showing the existing sampling locations at Plant A and Plant B
are presented in Figures J-l and J-2.
At the incinerator, stainless steel sampling lines lead to a
ground level sampling location. The temperature of the incin-
erated gases is 870°C and required cooling to 540°C before
introduction into the sampling train to prevent the glassware
from melting. This was achieved by air cooling of the sampling
line.
2. SAMPLING METHODS AND EQUIPMENT
a. Nitrogen and Sulfur Oxides
Method 6 was employed for SO2 determination and Method 7 was
used for sampling and analysis of NO . Since these methods are
Ji
96
-------
PLATFORM
X
-ABSORBER BY-PASS
ABSORBER VENT
SAMPLE LINE.
- 19-mm STAINLESS STEtt,
STEAM TRACED
.SAMPLE LINES
APPROXIMATaY0.9m
FROM MAIN PLATFORM
FLOOR
Figure J-l. Available sampling lines at Plant A.
EXIT TEMPERATURE
800 °C
41m
30-5m
SUPPLY GAS
OR H20 PORTS
MAIN
BURNERS
870 °C
ZONE-
\
,
'
,19- mm
STAINLESS STEEL
EXISTING
SAMPLING
LINE
». GROUND LEVEL
T SAMPLING PORT
1 PRESSURE
11 °m CONTROL VALVE
DEMISTER
- mm STAINLESS
STEEL SAMPLING LINE
— SAMPLING
PLATFORM
ABSORBER
COLUMN
71.6m
Figure J-2. Available sampling lines at Plant B.
97
-------
described in the Federal Register37/38 they will not be discussed
here. Measurements were made under steady state conditions.
b. Hydrogen Cyanide, Acrylonitrile and Acetonitrile
A separate absorption train was employed for sampling of hydrogen
cyanide, acrylonitrile and acetonitrile. The sampling train is
presented schematically in Figure J-3.
PLANT SAMPLING VALVE
tL.
ICE BATH -
CONTROL VALVE
-
s
~~l
—
-
-
I
/
— .
>'
"... '-••
\
~\
' —
;
!— .j.
/
" 1
. — ,
t
1
—
~,
i
SfflBli
&$$
K
p
—
HS)
^V
DISTILLED WATER 0.1 N KOH
SILICAGEL
ROTAMETER
PUMP
Figure J-3.
Sampling train for acrylonitrile, acetonitrile
and hydrogen cyanide emissions.
The train is an all-glass system which was connected to the
sampling line with Teflon tubing. It consists of four bubblers
and two impinger units all maintained at 0°C in an ice bath.
The first two units contained 0.0001 m3 of distilled water for
absorption of acrylonitrile and acetonitrile. The next two units
contained 0.0001 m3 of 0.IN KOH for absorption of hydrogen cya-
nide. The first four impingers were fitted with fritted-glass
bubblers. These impingers were followed by a dry impinger and
a silica gel impinger. The last impinger was connected to a dry
test meter (Type A2-110 American Meter Co.).
Sampling rates were adjusted to 0.001 m3/min and sampling was
continued for a period of 30 minutes. After completion of the
sampling run, the train was disconnected from the gas sampling
^Determination of Sulfur Dioxide Emissions from Stationary
Sources - Method 6. Federal Register, 36 (24):24882-24891,
1971.
Determination of Nitrogen Oxide Emissions from Stationary
Sources - Method 7. Federal Register, 36 (24) :24891-24893,
1971.
98
-------
line and the impinger contents transferred to clean sample
bottles. Each impinger and the connecting tubing was rinsed
three times with fresh portions of the collection liquid. All
samples were returned to MRC's Dayton Laboratory for analysis.
Preliminary experiments were conducted at the Dayton Laboratory
to test the feasibility of collecting acrylonitrile and aceto-
nitrile in distilled water. The sample generation and collection
system is presented in Figure J-4. An A.I.D. Model 309 Calibra-
tion System was employed to generate the nitriles via a diffusion
tube filled with 2.5 x 10~6 m3 of the liquid. Nitrogen gas was
admitted into the mixing chamber and this stream containing the
nitrile vapor underwent secondary dilution via a metered nitrogen
flow admitted at a 3-way stopcock just upstream of the sampling
train. The method of sample generation does not represent a
primary standard since the nitrile vapor composition can only be
estimated due to uncertainties in the diffusion coefficients and
their temperature dependence. An indication of the collection
efficiency is demonstrated by the data presented in Table J-l
where the distributions of the nitriles between the three im-
pingers are presented for two estimated concentration levels.
3-WAY STOPCOCK
FRITTED-GLASS BUBBLERS
TON2CYCLINDER
-MIXING CHAMBER
DIFFUSION TUBE
TO FLOWMETER
MODEL 309
Figure J-4. Laboratory sample generation and collection
system for acrylonitrile and acetonitrile.
99
-------
TABLE J-l. DISTRIBUTION OF ACRYLONITRILE AND ACETONITRILE
IN THREE TANDEM DISTILLED WATER IMPINGERS
Percent of total nitrile
Estimated gaseous collected in bubblers
Sample concentration, ppm v/v 1st 2nd 3rd
Acrylonitrile
Acrylonitrile
Acetonitrile
Acetonitrile
157
0.
64
0.
65
68
80
84
95
100
18
16
5
0
2
0
0
0
The acidic nature of hydrogen cyanide assures quantitative collec-
tion (99.5+%) in 0.1N KOH.
The analyses of the impinger contents presented in Table J-l were
conducted employing the gas chromatographic-flame ionization
method described in Section 3 of this appendix.
This sampling train was used to collect acrylonitrile, acetoni-
trile, and hydrogen cyanide from the absorber and the incinerator.
c. Carbon Monoxide, Propane, Propylene and Other Organic Species
Carbon monoxide, propane, and propylene from the absorber vent
were sampled using Tedlar bags. Background measurements taken
before sampling indicated that the bags contained <10 vppm of CO
and <1 ppm of hydrocarbons. Prior to sampling, the bags were
evacuated to <0.1 nun Hg pressure. A Teflon tube connected the bag
to the sampling line. The stopcock on each bag was closed and
taped and the bags returned to the laboratory for analysis.
d. Acrylonitrile Settling Pond Emissions
Since there are no data describing emissions from the acrylo-
nitrile settling pond, an open source sampling effort was used.
The settling ponds are covered by an oil film to moderate evapora-
tion of materials from the pond. The species of interest in this
case were assumed to be acrylonitrile and acetonitrile from the
plant process, and hydrocarbons from the oil film.
Since these emissions were diluted in an ambient air matrix, an
experimental ambient air sampling system was employed involving
sampling through a porous polymer packed tube.3^ The polymers
are chromatographic substrates which do not absorb water vapor
39Mienire, J. P., and M. W. Dietrich. Determination of Trace
Organics in Air and Water. Journal of Chromatographic Science,
11(11)-.559-570, 1973.
100
-------
but absorb hydrocarbon species such as higher (>C7) hydrocarbons,
acrylonitrile and acetonitrile.
The sampling system as shown in Figure J-5 consisted of a 6.4 mm
or 9.5 mm stainless steel tube 150 mm long packed with porous
polymer bead material. This sampling tube was attached to a pump
(Model MP-155 Metal Bellows Corp.), a rotometer with valve (Dwyer
0-0.14 m3/hr), and a gas meter (Type AI-110 American Meter Co.).
The pump was required due to pressure drop caused by the packing
in the tube.
SETTLING POND
EMISSIONS
STAINLESS STEft
PROBE
Figure J-5. Porous polymer tube sampling train.
In operation the tube was connected to the sample line and the
pump turned on. Samples were collected over 5 to 30 minute per-
iods and the barometric pressure, meter pressure and temperature
and gas volume were recorded. The hydrocarbon and organic emis-
sions were adsorbed on the packing and polar materials such as
water vapor pass through. After sampling, the tube was removed
from the train and capped with stainless steel tube closures.
3. ANALYSIS PROCEDURES
As discussed in Section 2, standard EPA methods of analysis as
published in the Federal Register were employed for quantifica-
tion of the emissions from the absorber and incinerator vents
where applicable. To date, no sampling or analytical methods
have been promulgated for determination of hydrogen cyanide,
acrylonitrile, or acetonitrile in stack gases.
101
-------
a. Hydrogen Cyanide
The following three methods for analysis of HCN in 0.1N caustic
media were considered for the acrylonitrile plant sampling effort:
(1) The National Institute for Occupational Safety and Health
(NIOSH) method (P+CAM 1116).l|0
(2) Reaction with chloramine-T followed by colorimetric measure-
ments with pyridine-pyrazolone reagent.1*1
(3) Reaction with chloramine-T and nicotinamide followed by
fluorometric analysis.42
The NIOSH method for HCN in work environments involves collection
of HCN with midget impingers containing 15 x 10~6 m3 of 0.1N NaOH
and subsequent measurement of cyanide ion with a specific ion
electrode. A detection level of 11 mg HCN/m3 (9.1 ppm v/v) is
attained for a 100-minute sampling period at a 0.001 m3/min
sampling rate. The method is listed by NIOSH as being in general
use or approved by most professional industrial hygiene analysts
but one that has not been thoroughly evaluated by NIOSH or any
of the professional societies. An interference could result from
the hydrolysis of o-hydroxynitriles (cyanohydrins) in all three
methods discussed here. Partial hydrolysis of these moities
could occur in the 0.1N NaOH solution with complete hydrolysis
occurring immediately in 0.4N NaOH.
In the colorimetric analysis of HCN by reaction with chloramine-T
followed by measurement with pyridine-pyrazolone reagent, the cya-
nide ion is first converted to cyanogen chloride by chloramine-T.
On reaction with the pyridine-pyrazolone reagent a blue dye is
formed and absorption read at 630 nm. For extracted color read-
ings the coefficient of variation is 3.9%, the sensitivity is
0.1 pg and the effective range is 0.2 to 2.0 vig.
The fluorometric procedure for HCN proceeds similarly to the
colorimetric reaction in that cyanide ion is converted to cyanogen
chloride by chloramine-T. The cyanogen chloride then cleaves the
t*°Liethe, W. The Analysis of Air Pollutants. Ann Arbor -
Humphery Science Publications, Ann Arbor, Michigan, 1970.
p. 227. [Used as NIOSH Physical and Chemical Analysis
Measurements (P+CAM) Procedure #116.]
41 Standard Methods for the Examination of Water and Wastewater,
American Public Health Association, Washington, D.C., 1971.
pp. 404-406.
42Hanker, J. S., R. M. Gamson, and H. Klapper. Fluorometric
Method for Estimation of Cyanide. Journal of Analytical
Chemistry, 29 (6):879-871, 1957.
102
-------
pyridine ring of the nicotinamide to produce a product which has
a strong blue fluorescence in alkaline media. A plot of fluores-
cence intensity versus cyanide concentration approximately follows
the Baugeur-Beer law. The detection limit of HCN using this
procedure is 0.2 microgram of cyanide and the relative standard
deviation for the method is ±10% at that level. This method has
been employed at the Dayton Laboratory of Monsanto Research
Corporation for measurement of thousands of CN~ samples over the
past six years. An Aminco-Bowman Spectrophotofluorometer is
employed at an excitation wavelength of 365 nm and an emission
wavelength of 456 nm.
The latter method of analysis for HCN was used for measurement of
the acrylonitrile plant samples. The primary basis for this
selection is one of cost in analyst time since similar samples are
analyzed daily in the Dayton Laboratory and no setup or precalibra-
tion is required. The latter method is both more sensitive and
accurate than either of the first two methods discussed.
As mentioned previously, a-hydroxynitriles (cyanohydrins) that
might be present in the emissions were determined as hydrogen
cyanide by this procedure. There was no evidence that a-hydroxy-
nitriles were present in the samples.
Hanker, et al.,1*2 have demonstrated that cyano-organophosphorus
compounds are retained on passing an air matrix through bubblers
filled with diethyl phthalate and that these bubblers pass hydro-
gen cyanide quantitatively. A sampling train identical in every
respect to that presented in Figure J-3 was employed for this
measurement, except that diethylphthalate was employed in the
first two impingers instead of distilled water. The contents of
the two 0.1N KOH impingers were then analyzed for free hydrogen
cyanide by the method presented previously.
b. Acrylonitrile and Acetonitrile
Three alternatives have been considered for sampling of acrylo-
nitrile and acetonitrile emissions. These include:
(1) The NIOSH method P+CAM #127. **3
(2) A variation on the NIOSH method employing porous polymer
sorbent rather than activated carbon.*0
(3) Collection of these species in distilled water.
**3White, L. D., D. G. Taylor, P. A. Mauer, and R. E. Kupel. A
Convenient Optimized Method for the Analysis of Selected Solvent
Vapors in the Industrial Atmosphere. American Industrial
Hygiene Association Journal, 31 (2):225-232, 1970. [Used as
NIOSH Physical and Chemical Analysis Measurements (P+CAM)
Procedure #127.]
103
-------
The NIOSH method for acrylonitrile and acetonitrile vapors in
work environment atmospheres is based on the collection of the
organic vapors on activated carbon with subsequent desorption
of the species with CSa followed by gas chromatographic analyses
with a flame ionization detector. *** The GC/FID approach is com-
mon to all three methods considered here. For 0.01 m3 of sampled
air the detection limit for acrylonitrile is 45 mg/m3 while that
for acetonitrile is 70 mg/m3. This method is rated by NIOSH as
a method not used by industrial hygiene analysts but one which
gives promise for the determination of organic substances. The
drawbacks to using this approach for determination of the nitriles
are (1) overloading of the activated carbon due to the high vapor
content of the absorber vent stream (5.5 to 11.0 mole %), (2) the
variable desorption efficiency for various organic species, and
(3) the unknown capacity before breakthrough, especially since
water would deactivate adsorption sites. It is projected that an
extensive laboratory effort would be required to validate this
approach for determination of acrylonitrile plant emissions.
An improvement in this approach would be realized employing
porous polymer packings such as Chromasorb 101, Chromasorb 105
or Tenex GC. The sorbents are not affected by water vapor which
is passed through without adsorption. In addition, nonpolar and
moderately polar organic emissions can be thermally desorbed from
the polymer packing without the use of CS2- This approach, how-
ever, would require a laboratory effort to establish adsorption
capacity and breakthrough conditions before sampling could be
conducted in the field.
The third method involves the collection of the nitrile vapors
in distilled water impingers similar to the approach employed
for HCN vapors in 0.1N KOH bubblers. Analysis of acrylonitrile
and acetonitrile will be performed by gas chromatographic tech-
niques using a Hewlett-Packard HP 5750 Chromatograph with a flame
ionization detector. The gas chromatographic column is a
0.9 m x 6.4 mm stainless steel column containing 20% THEED on
250 to 600 ym (30 to 60 mesh) Chromosorb W (acid washed).
Acrylonitrile retention time is 1.5 minutes while that for aceto-
nitrile is 2.5 minutes. The detection limits for both nitriles
is 50 ppb. The standard deviation for acrylonitrile at this
concentration is ±7.7% while the standard deviation for aceto-
nitrile at 0.20 ppm is ±1.8%. As was the case with the HCN
analysis recommended, the Dayton Laboratory has conducted several
thousand acrylonitrile analyses by the GC-FID approach over the
past six years. This approach was used on this program.
c. Carbon Monoxide, Propane, Propylene
Two separate systems were employed to measure CO and hydrocarbon
grab samples from the absorber vent. The first approach employed
an automated CO, CHt,, total hydrocarbon analyzer developed by
Monsanto Research Corporation which measures the three components
104
-------
to a sensitivity of 0.1 ppm. The instrument is a chromatographic
system where CO and CH^ are separated initially by a precolumn.
The CO is then reduced to methane over a nickel catalyst and the
two time resolved methane peaks determined by by-passing the pre-
column and catalyst system and passing a portion of the sample
directly to the flame ionization detector.
The second approach employed gas chromatographic techniques with
flame ionization detection to identify and quantify the individual
hydrocarbon species in the Tedlar bag samples. Here, several
options existed:
(a) Direct gas chromatographic analysis with a flame
ionization detector.
(b) Analysis by tandem coupled gas chromatograph-mass
spectrometer on samples "as received" or concen-
trated by cryogenic means.
Employing direct chromatographic analysis the low molecular weight
hydrocarbons, e.g., methane, ethane, ethylene, propane, propylene
and butanes, were identified by retention data and quantified
(down to 0.1 ppm) by measuring the response of individual compo-
nents with a flame ionization detector. Quantification is real-
ized by comparing responses to those of standard gas mixtures. A
3 m x 6.4 mm Porapak Q chromatographic column in tandem with a
3 m x 6.4 mm Porapak R column, ora0.9mx2mm Carbosieve B
column was used in these analyses.
Preliminary examination of a sample indicated a number of unex-
pected components, and tandem coupled gas chromatography/mass
spectrometric analyses were performed to identify the components.
The analytical column which was employed for this purpose was a
1.4 m column packed with Porapak Q. Quantitative analysis was
conducted by measurement of gas chromatographic peak areas or
peak heights of components in the "as received" samples.
d. Analysis of Ambient Air at Acrylonitrile Settling Pond
The analysis approach used was essentially that discussed for
analysis of acrylonitrile and acetonitrile. The porous polymer
tube was employed to obtain integrated ambient air samples down-
wind and upwind of the settling pond. The tube was designed so
that it was directly interfaceable with a gas chromatograph.
Desorption of the collected species was initiated using carrier
flow and elevated temperature directly onto the analytical column
of the gas chromatograph. Air flow rates of 0.002 mvmin and a
10-minute sampling time were used and components present at
0.5 ug/m3 in the ambient air were measured with a flame ioniza-
tion detector capable of detecting 10 ng.
105
-------
GLOSSARY
absorber: Absorption column used to recover acrylonitrile, ace-
tonitrile, hydrogen cyanide, oxygenated hydrocarbons, organic
polymers, and other hydrocarbons from the ammonia-free reac-
tor product stream.
acrylonitrile: Colorless, low viscosity organic liquid having the
chemical formula, CH2 = CHCN.
affected population: Number of nonplant persons exposed to con-
centrations of airborne materials which are present in con-
centrations greater than a determined hazard factor.
ammoxidation: Oxidation of a material in the presence of
ammonia.
atmospheric stability class: Class used to designate degree of
turbulent mixing in the atmosphere.
Catalyst A: Bismuth/molybdenum catalyst used in the SOHIO pro-
cess from 1960 to 1967.
Catalyst 21: Depleted uranium catalyst used in the SOHIO process
from 1967 through 1973.
Catalyst 41: Catalyst based on bismuth phosphomolybdate and
currently (1976) used in the SOHIO process.
criteria pollutant: Emission species for which ambient air
quality standards have been established; these include par-
ticulates, sulfur dioxide, nitrogen dioxide, carbon monoxide,
and nonmethane hydrocarbons (recommended guidelines).
deep well pond: Nonaerated lagoon used for undissolved solids
removal from acrylonitrile plant wastewater prior to deep
well injection of the wastewater.
emission factor: Weight of material emitted to the atmosphere
per unit of acrylonitrile produced, e.g., g material/kg
product acrylonitrile.
flare: Combustion device used for the ultimate disposal of small
continuous flow hydrocarbon streams and intermittent hydro-
carbon streams.
106
-------
incinerator: Thermal oxidizer used for ultimate disposal of
acetonitrile and hydrogen cyanide by-products and plant
residues.
noncriteria pollutant: Emission species for which no ambient
air quality standards have been established.
product transport loading facility: Facility used at acrylo-
nitrile plants to load product acrylonitrile into railroad
tank cars and tank trucks.
quencher: Device used in acrylonitrile manufacture to cool
reactor product gases and to remove excess ammonia prior
to product recovery in the absorber.
SOHIO process: process for ammoxidation of propylene which is
licensed by SOHIO (The Standard Oil Company) for production
of acrylonitrile.
source severity: To assess the environmental impact of atmos-
pheric emissions from acrylonitrile manufacture, the source
severity for each material emitted from each emission point
was estimated. Source severity is defined as the pollutant
concentration to which the population may be exposed divided
by an "acceptable concentration". The exposure concentration
is the time-averaged maximum ground level concentration as
determined by Gaussian plume dispersion methodology. The
"acceptable concentration" is that pollutant concentration at
which an incipient adverse health effect is assumed to occur.
For criteria pollutants, it is the corresponding primary
ambient air quality standard. For noncriteria pollutants, it
is a surrogate air quality standard as determined by reducing
TLV's for chemical substances using an appropriate safety
factor.
tank outage: Distance from liquid surface to the top of a fixed
roof storage tank.
107
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CONVERSION FACTORS AND METRIC PREFIXES44
CONVERSION FACTORS
To convert from
to
Multiply by
degree Celsius (°C)
degree Kelvin (K)
gram (g)
gram/second (g/s)
joule (J)
kilogram (kg)
kilogram (kg)
kilogram/meter3 (kg/m3)
kilometer2 (km2)
meter (m)
meter (m)
meter3 (m3)
meter 3 (m 3)
meter3 (m3)
meter 3/kilogram (m3kg)
metric ton
pascal (Pa)
degree Fahrenheit (°F)
degree Celsius (°C°
pound-mass
pounds/hour
British thermal unit (Btu)
pound mass (Ib mass avoirdupois)
ton (short, 2,000 Ib mass)
Ib mass/foot3
mile2
foot
inch
barrel (42 gal)
foot3
gallon (U.S. liquid)
milliliter/gram (ml/g)
pound-mass
pound-force/inch2 (psi)
1.8
+ 32
to = t- - 273.15
2.205 x 10~3
7.930
9.479 x 10"**
2.204
1.102 x 10~3
6.243 x 10~2
2.591
3.281
3.937 x 10
6.293
3.531 x 10
2.642 x 102
1.000 x 103
2.205 x 103
1.450 x ID'4
METRIC PREFIXES
Multiplication
Prefix
mega
kilo
milli
micro
Symbol
M
k
m
M
factor
106
103
ID'3
10~6
1
1
1
1
Example
MJ = 1 x 106 joules
kPa = 1 x 10 3 pascals
mg - 1 x 10~ 3 gram
m = 1 x 10~6 meter
44Metric Practice Guide. ASTM Designation E 380-74, American
Society for Testing and Materials, Philadelphia, Pennsylvania,
November 1974. 34 pp.
108
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TECHNICAL REPORT DATA
(Please read laurucnons on the reverse before completing)
1. REPORT NO.
EPA-600/2-77-107J
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
SOURCE ASSESSMENT:
(Air Emissions)
Acrylonitrile Manufacture
6. REPORT DATE
September 1977
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
T.W. Hughes and D.A. Horn
8. PERFORMING ORGANIZATION REPORT NO.
MRC-DA-537
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Monsanto Research Corporation
1515 Nicholas Road
Dayton, Ohio 45407
1O. PROGRAM ELEMENT NO.
1AB015; ROAP 21AXM-071
11. CONTRACT/GRANT NO
68-02-1874
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Task Final; 5/74-7/77
14. SPONSORING AGENCY CODE
EPA/600/13
is. SUPPLEMENTARY NOTES JERL-RTP task officer for this report is Irvin A. Jefcoat, Mail
Drop 62, 919/541-2547. Related reports are also in the EPA-600/2-76-032 series.
16. ABSTRACT
The report gives results of an analysis of atmospheric emissions from
propylene-based acrylonitrile manufacturing plants. Uncontrolled and controlled
emission factors are given for each species emitted to the atmosphere from each
source within a typical plant, based on field sampling data and engineering estimates.
Emissions data are used to calculate several factors designed to quantify the hazard
potential of the emissions. A detailed process description and flow sheet are presen-
ted for the SOHIO process. Present and future aspects of pollution control technology
in the industry are discussed. Economic and production trends in the acrylonitrile
industry and in each of the industries that are consumers of acrylonitrile are
analyzed.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Croup
Air Pollution
Acrylonitrile
Propylene
Industrial Processes
Air Pollution Control
Stationary Sources
Source Assessment
Emission Factors
SOHIO Process
13B
07C
13H
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (ThisReport)
Unclassified
21 NO. OF PAGES
120
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
109
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