United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-450/3-81-002
January 1981
Air
AMMONIUM NITRATE
AP-42 Section 6.8
Reference Number
1
Ammonium Nitrate
Manufacturing
Industry — Technical
Document
• Note: This is a reference cited in AP 42, Compilation of Air Pollutant Emission Factors, Volume I Stationary';
\Point and Area Sources. AP42 is located on the EPA web site at www.epa.gov/ttn/chief/ap42/ ;
|The file name refers to the reference number, the AP42 chapter and section. The file name ;
>"ref02_c01s02.pdf" would mean the reference is from AP42 chapter 1 section 2. The reference may be i
I from a previous version of the section and no longer cited. The primary source should always be checked.;
-------
EPA-450/3-81-002
Ammonium Nitrate
Manufacturing
Industry — Technical
Document
Emission Standards and Engineering Division
Contract No. 68-02-3058
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise, and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
January 1981
-------
This report has been reviewed by the Emission Standards and Engineering
Division, Office of Air Duality Planning and Standards, Office of Air, Noise,
and Radiation, Environmental Protection Agency, and approved for publication.
Mention of company or product names does not constitute endorsement by EPA.
Copies may be obtained, for a fee, from the National Technical Information
Service, 5285 Port Royal Poad, Springfield, VA. 22161.
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TABLE OF CONTENTS
Chapter Page
1.0 Introduction and Summary 1-1
1.1 Purpose 1-1
1.2 Summary 1-1
2.0 The Ammonium Nitrate Industry 2-1
2.1 Industry Structure 2-1
2.2 Ammonium Nitrate Products and End Uses 2-4
2.3 References 2-8
3.0 Processes and Their Emissions 3-1
3.1 Introduction 3-1
3.2 Description of Processes and Emissions 3-9
3.3 References 3-49
4.0 Emission Control Techniques 4-1
4.1 Overview of Control Techniques 4-1
4.2 Description of Control Techniques 4-4
4.3 Emission Test Data 4-28
4.4 Evaluation of Control Device Performance 4-35
4.5 References 4-43
5.0 Model Plants and Control Alternatives 5-1
5.1 Model Plants 5-1
5.2 Determination of Existing Control Levels 5-11
5.3 Control Options 5-20
5.4 Control Alternatives 5-28
5.5 References 5-36
6.0 Environmental Impacts 6-1
6.1 Air Pollution Impact 6-1
6.2 Water Pollution Impact 6-6
6.3 Solid Waste Impact 6-6
6.4 Energy Impact 6-6
6.5 Other Impacts 6-7
6.6 References 6-9
7.0 Cost Analysis 7-1
7.1 Cost Analysis of Control Alternatives 7-1
7.2 Other Cost Considerations 7-28
7.3 References 7-29
Appendix A A-l
Appendix B B-l
ii
-------
LIST OF TABLES
Table Page
1-1 Summary of Control Alternatives 1-3
1-2 Impact of the Control Alternatives on Particulate
Emissions and Product Price 1-4
2-1 Ammonium Nitrate Producers-Plants, Locations, and
Capacities 2-2
2-2 Ammonium Nitrate Production, Capacity, and Capacity
Utilization Rates 2-5
2-3 Number of Plants by Type of Solid Produced and
Capacity, 1980 2-6
3-1 Properties of Solid Ammonium Nitrate 3-2
3-2 EPA Test Data on Uncontrolled Emissions from Sources
in the Ammonium Nitrate Industry 3-10
3-3 Ammonium Nitrate Prill Tower Parameters (High Density
Production) 3-19
3-4 Ammonium Nitrate Prill Tower Parameters (Low Density
Production) 3-20
3-5 Melt Stream Characteristics for Low Density Prill
Production 3-22
3-6 Melt Stream Characteristics for High Density Prill
Production 3-22
3-7 Uncontrolled Emissions from Prill Towers 3-24
3-8 Uncontrolled Emissions from Granulators 3-29
3-9 Cooler Operating Parameters 3-33
3-10 Low Density Predryer Operating Parameters 3-34
3-11 Low Density Prill Dryer Operating Parameters . . . 3-35
3-12 Uncontrolled Emissions from Coolers 3-41
3-13 Uncontrolled Emissions from Low Density Rotary
Drum Predryers 3-44
iii
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3-14
4-1
4-2
4-3
5-1
5-2
5-3
5-4
5-5
5-6
5-7a
5-7b
5-7c
5-8a
5-8b
5-8c
5-9a
Uncontrolled Emissions from Low Density Rotary
Emission Control Techniques Used by the Ammonium
High Density and Low Density Prill Tower and
Solids Finishing Process Emissions
Model Ammonium Nitrate Plants
Raw Material Requirements for the Model Ammonium
Nitrate Plants
Emissions Standards Affecting Ammonium Nitrate
Plants
Allowable Emissions by Plant Size
Uncontrolled Emissions and Emissions Control
Techniques for Solid Ammonium Nitrate Processing
Existing Level of Control (ELOC) Emissions and
Control Equipment for Ammonium Nitrate
Facilities
Emission Parameters: Ammonium Nitrate High Density
Prilling Plant - 363 Mg/Day (400 Tons Per Day). .
Emission Parameters: Ammonium Nitrate High Density
Prilling Plant - 726 Mg/Day (800 Tons Per Day). .
Emission Parameters: Ammonium Nitrate High Density
Prilling Plant - 1089 Mg/Day (1200 Tons Per Day).
Emission Parameters: Ammonium Nitrate Low Density
Prilling Plant - 181 Mg/Day (200 Tons Per Day) .
Emission Parameters: Ammonium Nitrate Low Density
Prilling Plant - 363 Mg/Day (400 Tons Per Day). .
Emission Parameters: Ammonium Nitrate Low Density
Prilling Plant - 816 Mg/Day (900 Tons Per Day). .
Emission Parameters: Ammonium Nitrate Granulation
Plant - 363 Kq/Dav (400 Tons Per Day)
3-45
4-3
4-29
4-36
5-2
5-10
5-12
5-15
5-17
5-18
5-22
5-23
5-24
5-25
5-26
5-27
5-29
iv
-------
5-9b
5-9c
5-10
5-n
5-12
6-1
6-2
6-3
6-4
7-1
7-2
7-3
7-4
7-5a
7-5b
7-5c
7-5d
7-6
Emission Parameters: Ammonium Nitrate Granulation
Plant - 726 Kg/Day (800 Tons Per Day)
Emission Parameters: Ammonium Nitrate Granulation
Plant - 1,089 Mg/Day (1,200 Tons Per Day) ....
Control Alternatives for Ammonium Nitrate Plants.
Emission Factors
Control Alternatives for Model Ammonium Nitrate
Plants
Emission Factors and Reductions for Control
Alternatives
Total Annual Reduction Over Existing Level of
Control of Particulate Emissions for Control
Alternatives Mg/Year (Tons/Year)
Secondary Air Impacts over ELOC for each Model
Plant and Control Alternative
Energy Requirements for Model Plants and Control
Alternatives
Model Ammonium Nitrate Plants for Cost Estimates.
Emission Factors
Control Alternatives for Model Ammonium Nitrate
Plants
Control Equipment Specifications
Major Equipment Requirements for Control of
High Density Prill Towers 363 Mg/Day (400 TPD)
Facility
Major Equipment Requirements for Control of Low
Density Prill Towers 363 Mg/Day (400 TPD) Facility
Major Equipment Requirements for Control of Granul
363 Mg/Day (400 TPD) Facility
Major Equipment Requirements for Control of Cooler
Dryers, Predryers 363 Mg/Day (400 TPD) Facility .
Component Capital Cost Factors for Wet Scrubbers
as a Function of Equipment Cost, 0
5-30
5-31
5-33
5-34
5-35
6-2
6-4
6-5
6-8
7-2
7-3
7-4
7-7
7-8
7-11
a tors
7-14
s,
7-15
7-18
-------
7-7 Capital Cost for the Control of Individual Sources
in 363 Mg/Day (400 TPD) Model Ammonium Nitrate
Plants 7-19
7-8 Capital Costs of Control Alternatives for Model
Plants 7-20
7-9 Basis for Scrubber Annualized Cost Estimates
(1980) 7-21
7-10 Annualized Cost for the Control of Individual
Sources in 363 Mg/Day (400 TPD) Model Ammonium
Nitrate Plants 7-23
7-11 Annualized Cost and Cost Effectiveness of Control
Alternatives for Model Ammonium Nitrate
Facilities 7-25
7-12 Base Costs of Ammonium Nitrate Plants 7-27
vi
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LIST OF FIGURES
Figure Page
3-1 Ammonium nitrate processing steps 3-3
3-2 High density ammonium nitrate prilling process flow
diagram 3-5
3-3 Low density ammonium nitrate prilling process flow
diagram 3-6
3-4 Drum granulation or pan granulation process flow
diagram 3-7
3-5 Single stage neutralizer 3-12
3-6 Air swept falling film evaporator 3-14
3-7 General prill tower flow diagram 3-15
3-8 Multiple spray plate or nozzle arrangement 3-16
3-9 Spinning bucket 3-17
3-10 Rotary drum granulator. . . 3-26
3-11 Top view of pan granulator. . , 3-30
3-12 Rotary drum cooler 3-36
3-13 Fluid bed cooler 3-39
4-1 Prill tower/collection hood configuration 4-5
4-2 Detail of a wetted fibrous filter scrubber 4-7
4-3 Collection efficiency vs. particle size for a wetted
fibrous filter scrubber 4-9
4-4 Tray-type scrubber 4-10
4-5 Standard fractional efficiency for tray-type scrubber . . 4-12
4-6 Effect of pressure drop on tray-type scrubber efficiency 4-13
vii
-------
4-7 Spray tower scrubber 4-14
4-8 Venturi and cyclonic scrubber 4-17
4-9 Collection efficiency vs. particle diameter for a venturi
scrubber 4-18
4-10 Typical entrainment scrubber 4-20
4-11 Collection efficiency of entrainment scrubbers as a function
of particle size and pressure drop 4-21
4-12 Mechanical centrifugal scrubber 4-23
4-13 Wet cyclone scrubber 4-24
4-14 Fabric filter 4-26
4-15 Particle size distribution from the bypass and the scrubber
inlet at a low density prill tower 4-31
4-16 Particle size distribution of uncontrolled emissions from
a rotary drum granulator 4-33
4-17 Average particle size distribution from solids finishing
processes 4-34
4-18 Controlled emissions from solids finishing processes
tested by EPA 4-40
5-1 High density prill plant 5-4
5-2 Low density prill plant 5-5
5-3 363 Hg/day (400 TPD) granulation plant 5-6
5-4 726 Mg/day (800 TPD) granulation plant 5-7
5-5 1089 Mg/day (1200 TPD) granulation plant 5-8
7-1 Control equipment configuration for high density prill
towers - 363 Mg/day (400 TPD) 7-10
7-2 Control equipment configuration for low density prill
towers - 363 Mg/day (400 TPD) 7-13
viii
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1.0 INTRODUCTION AND SUMMARY
1.1 PURPOSE
The purpose of this document is to present information on the
emission levels, control techniques and costs associated with the
control of particulate emission sources and facilities in the ammonium
nitrate (AN) solids producing industry. The industry, emission sources
and existing control techniques are described and discussed. Control of
solution formation processes and emissions are not discussed, although
uncontrolled emissions data are presented.
1.2 SUMMARY
1.2.1 Industry Structure
The ammonium nitrate industry produces AN in both solid and solution
form. Solids are primarily manufactured in three sizes: high density
prills, low density prills and granules. High density prills and granules
are used as fertilizer, while low density_prills are used as fertilizer
or inexplosives^. Alnmonium nitrate solutions are used as fertilizer or
are concentrated for use in solids formation processes. There are
66 plants in the United States producing either AN solution alone or
both solution and solids. In 1980, ammonium nitrate production is
expected to be 10.08 Tg (11.10 million tons).
1.2.2 Processes and Emissions
The production of AN can be divided into several steps or unit
processes. Unit processes in the ammonium nitrate industry include AN
solution synthesis, solution concentration, solids formation (prilling
and granulation), solids finishing, solids screening, solids coating,
and bagging and/or bulk shipping. Uncontrolled AN particulate emission
rates from these unit processes range from 0.03 g/kg (0.06 Ib/ton) of AN
produced for the concentration process to 147.2 g/kg (294.6 Ib/ton) of
AN produced for a solids producing process (granulation). The most
1-1
-------
effective control device used to control AN participate emissions is a
wet scrubber.
1.2.3 Model Plants and Control Alternatives
Model plants represent ammonium nitrate plants currently operating
and those expected to be constructed, modified or expanded in the near
future. The model plants defined in this study have production capacities
that range from 181 Mg/day (200 tons/day) to 1089 Mg/day (1200 tons/day).
Control devices that exhibit various levels of removal efficiency were
identified for each source within the model plants. Several control
alternatives were selected for each model plant. The control alternatives
are based upon combinations of control devices applied to the emission
sources within the plant.
1.2.4 Economic and Environmental Impacts
Table 1-1 presents a summary of the control alternatives applied to
the model plants. The impact of these control alternatives on the
product price and the amount of particulate emissions is presented in
Table 1-2. Based on a product price of $100/Mg ($91/ton), the control
alternatives increase product price from 2 to 11 percent. Environmental
impacts which could result from applying emission control devices
include water quality, solid waste, and primary and secondary air quality
impacts. There are no water quality or solid waste impacts attributable
to the use of wet scrubbers for AN emissions control.
The primary air quality impact is the reduction in particulate
emissions from sources in the ammonium nitrate industry. Reductions
over existing levels of control range from 46 to 93 percent for prilling
plants and 68 percent for granulation plants. Small secondary air
impacts exist due to increased power plant particulate emissions resulting
from the energy requirements of the control devices. A negative secondary
air impact occurs because the energy requirements for the control alternatives
are less than the energy requirements for the existing levels of control.
The percent secondary impact relative to plant-wide emission reductions
ranges from -0.7 percent for a high density prill plant to 1.4 percent
for a low density prill plant.
1-2
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TABLE 1-1. SUMMARY OF CONTROL ALTERNATIVES*
CO
Model
Plant
Number
H 1-3 High Density
Prilling
L 1-3 Low Density
Prilling
G 1-3 Granulation
Control
Alternative
1 (ELOC)
2
3
4
4a
1 (ELOC)
2
3
4
1 (ELOC)
2
Prill Tower
0
0
X (Option 1)
X (Option 2)
X (Option 3)
Prill Tower
0
0
X (Option 1)
X (Option 2)
Granulator
0
X
Cooler
0
X
X
X
X
Predryer,
dryer
and cooler
0
X
X
X
Cooler
0
X
*0ptions 1, 2, and 3 correspond to different control devices and different levels of control for the
prill towers as explained in Chapter 5.
0 - Existing Level of Control (ELOC)
X - Optional Control
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TABLE 1-2. IMPACT OF THE CONTROL ALTERNATIVES ON
PARTICULATE EMISSIONS AND PRODUCT PRICE
Production
Capacity
Mg/Day
(Tons/Day)
Ammonium Nitrate Partlculate Emissions Effect of Control Alternative on Product Price
g/kg AN produced $/Hg AN produced
(Ib/ton AN produced) ($/ton AN produced)
Control Alternatives Control Alternatives
1
2
3
4
4a 1
2
3
4
4a
High Density Prill Plants
Low
lf-1
H-2
H-3
Density Prill Plants
L-1
L-Z
L-3
363
(400)
726
(800)
1089
(1200)
181
(200)
363
(400)
816
(900)
1.40
(2.80)
1.40
(2.80)
1.40
(2.80)
2.80
(5.60)
2.80
(5.60)
2.80
(5.60)
0.75
(1,50)
0.75
(1.50)
0.75
(1.50)
0.85
(1.70)
0.85
(1.70)
0.85
(1.70)
0.30
(0.60)
0.30
(0.60)
0.30
(0.60)
0.40
(0.80)
0.40
(0.80)
0.40
(0.80)
0.10
(0.20)
0.10
(0.20)
0.10
(0.20)
0.20
(0.40)
0.20
(0.40)
0.20
(0..40)
0.10 3.77
(0.20) (3.42)
0.10 3.12
(0.20) (2.83)
0.10 2.87
(0.20) (2.60)
2.88
' (2.61)
2.08
8 (1.89)
. 1.64
' (1.49)
3.84
(3.58)
3.25
(2.95)
2.97
(2.69)
3.65
(3.31)
2.60
(2.36)
2.05
(1.86)
3.31
(3.00)
2.73
(2.48)
2.58
(2.34)
6.14
(5.57)
4.35
(3.95)
3.46
(3.14)
8.36
(7.58)
7.44
(6.75)
7.22
(6.55)
11.29
(10.24)
9.47
(8.59)
7.97
(7.23)
2.61
(2.37)
2.25
(2.04)
2.03
(1.84)
a
a
a
Granulation Plants
6-1
G-2
G-3
363
(400)
726
(800)
1089
(1200)
0.95
(1.90)
0.95
(1.90)
0.95
(1.90)
0.30
(0.60)
0.30
(0.60)
0.30
(0.60)
a
a
a
a
a
a
-6.25b
a (-5.67)
-6.25b
8 (-5.67)
-6.25b
3 (-5.67)
-6.10b
(-5.53)
-6.10b
(-5.53)
-6.106
(-5.53)
a
a
a
a
a
a
a
a
a
aTh1s alternative does not apply to this model plant.
For granulation plants, the Impact on product price would be negative since the value of the recovered product exceeds
the control equipment costs.
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2.0 THE AMMONIUM NITRATE INDUSTRY
The purpose of this chapter is to describe the ammonium nitrate
(AN) industry. Section 2.1 presents the industry structure, history,
and growth, while Section 2.2 discusses the types of products and their
uses.
2.1 INDUSTRY STRUCTURE
Ammonium nitrate, or Norway saltpeter (NH. NO.,), is a hygroscopic
colorless solid which is produced from ammonia and nitric acid. Ammonium
nitrate is an oxidant containing a high proportion of nitrogen (33.5 percent
by weight), which makes it desirable for manufacture of explosives and
for use as a nitrogen fertilizer.
During World War II, the ammonium nitrate industry (SIC 28731) was
greatly expanded by the U.S. Government in order to manufacture munitions.
Following the war, the federal government sold the ammonium nitrate
plants to private industries who began marketing ammonium nitrate as a
fertilizer. Early product drawbacks and consumer reluctance were soon
overcome and ammonium nitrate developed into a major fertilizer compound.
Presently in the United States, 41 companies are operating 66 ammonium
nitrate plants. Total 1980 production capacity for the industry is
estimated to be 10.08 Tg (11,101,000 tons) of ammonium nitrate. Table 2-1
contains a listing of ammonium nitrate plants, their location, the type
of product they manufacture, their production capacity, and the year
they began production.
Historically, the Southeast has shown the greatest growth in production
capacity, while the Northeast has shown the greatest decline. At present
the largest ammonium nitrate producing area lies in the central and
southeastern part of the country. The top six AN producing states,
Kansas, Missouri, Oklahoma, Louisiana, Mississippi and Georgia, account
for 47 percent of total U. S. ammonium nitrate production capacity.
2-1
-------
TABLE 2-1. AMMONIUM NITRATE PRODUCERS —
PLANTS, LOCATIONS, AND CAPACITIES'
Company Name
Ai- Products and Cf.ec. Ir.z.
Allied Chemical Corp.
American Cyanamld Co.
Apache Powder Co.
Bison Nitrogen Products
Calumet Nitrogen
Center Plains Industries
CF Industries. Inc.
The Coastal Corp.
Wycon Chen. Co.
Columbia Nitrogen Corp.
Cominco American, Inc.
E.I. Dupont de Nemours 4 Co.
Escambia Chemicals
Esmark, Inc.
Estech Gen. Chems. Corp.
Farmland Industries, Inc.
Getty Oil Co.
Hawkeye Chen. Co., subs.
Good pasture. Inc.
W. R. Grace and Co.
Gulf Oil Co.
Hercules, Inc.
Illinois Nitrogen Corp.
Kaiser Aluminum & Chea. Co.
Mississippi Chen. Co.
Plant Location
TcilSaCOia, ru
Helena, AR
Geismar, LA
Omaha, NB
Hannibal, MO
Benson, AZ
Woodward. OK
Hammond, IN
Odessa. TX
Donaldsonvllle, LA
Fremont, MB
Or lean, NY
Terre Haute. IN
Tunis, NCb
Tyner, TN
Cheyenne. WY
Augusta, Ga
Beatrice, NB
Seneca. IL
Pace, fl
Beaumont, TX
Dodge City, KS
Lawrence, KS
Clinton, I A
Dlmitt. TX
Wilmington, NC
Pittsburg, KS
Bessemer, AL
Carthage, MO
Donora, PA
Hercules, CA
Louisiana. MO
Marseilles, IL
Sainbridge, GA
North Send, OH
Savannah, GA
Tampa, FL
Yazoo City, MS
Annual
Capacity
(103 Hg)
'3*
91
365
102
150
112
105
50
75
703
30
64
145
363
213
66
539
157
179
90
1B1
73
417
132
28
197
387
23
14
136
126
454
126
54
95
229
47
562
Form of AN* Date
solutions, MI)
prills
Solutions
Solutions
Solutions
HO & LO prills
LD prills
Solutions
Solutions, (captive
for nitrogen solutions)
Solutions
Solutions
Solutions
Solutions, LO
prills
Solutions, HO
prills
Solutions, HO
prills
Solutions, HO
prills
Solutions, LO
& HO prills
Granular
HO 4 LD prills
HD prills
Solutions, HD
pri 1 1 s
Solutions
Solutions, HO
prills
Solutions, HD
i LD prills
Solutions
Solutions, LO
prills
LD prills
Grains
Grains
LD prills
Solutions. LD
prills
Solutions, LD
prills
Solutions, HD
prills
Solutions
Solutions
Solutions, LD
prills
Solutions
Solutions, HO
prills
on Stream
1356
1967
1967
1956
1966
1945
1978
N/A
N/A
1978
1966
1967
1964
1969
1962
1965
1963
1966
1967
1980
1967
1975
1954
1963
1971
1963
1940
1955
1966
1969
N/A
1961
1964
1965
1965
1957
1960
1951
2-2
-------
TABLE 2-1. (continued)
Company Name
Monsanto Co.
N-ltram, Inc.
N-Ren Corporation
Occidental Chemical Co.
Phillips Pacific Chem. Co.
Phillips Petroleum Co.
Reichhold Chemicals
J. R. Slmplot Co.
Standard 011 of CA
Chevron Chem. Co.
Standard Oil of Ohio
Vistron Corp., subs.
Tennessee Valley Authority
Terra Chems. International
Tyler Corp.
Atlas Powder Corp., subs.
Union Oil of California
U. S. Army
U. S. Steel Corp.
Valley Nitrogen Producers
Williams Co.
Agrlco Chem. Co.
Total U. S. domestic capacity
Plant Location
El Dorado, AR
Lullng, LA
Tampa, FL
Carlsbad, KM
E. Oubuque, IL
Pine Bend, MM
Pryor. OK
Hanford, CA
Finley. WA
Beatrice, NB
Etter, TX
St. Helens. OR
Pocatello. ID
fort Madison. IA
Kennewick, WA
Richmond. CA
Lima. OH
Muscle Shoals. AL
Port Neal. I A
Joplln, MO
Tamaqua, PA
Brea. CA
Klngsport, TO
Cherokee, AL
Crystal City. NO
Geneva. UT
EL Centro. CA
Helm. CA
Verdigris, OK
Annual
Capacity
(103 Mg)
227
181
272
87
83
209
139
20
40
68
163
22
IB
172
214
68
58
39
130
146
14
113
N/A
136
223
91
40
40
478
10,081
Form of AN*
HD prills
HD & LO prills
Solutions. LD
prills
LD prills
Solutions
Solutions, HD
& LO prills
Solutions,
granular
Solutions
Solutions
Solutions,
LD prills
Solutions
Solutions
Solutions.
granular
Solutions,
granular
Solutions
Solutions
Solutions
Solutions. HD
prills
HO i LD prills
Crystal
Solutions, HD
prills
N/A
Solutions, HD
prills
Solutions, LD
prills
LD prills
Solutions
Solutions
Solutions
Date on Stream
1949
1954
1963
1976
N/A
1962
1967
1965
1963
1965
1950
1968
1974
1961
1960
N/A
1956
1972
1967
1958
1956
1955
1967
1962
1954
1957
1968
1976
1975
aLO « Low density prills; HD • High density prills.
Temporarily closed.
2-3
-------
Table 2-2 presents the historical production capacity and utilization
of the ammonium nitrate industry. Ammonium nitrate production capacity
has more than doubled since 1960, with major expansion occurring between
1961 and 1969. Due to fluctuations in the market, ammonium nitrate
plants have historically operated at between 63 and 87 percent of capacity.
The average utilization has been 70.5 percent. The largest utilization
occurred in the years 1974-1975, when an increase in energy and feedstock
prices, along with a high world demand for fertilizer caused a significant
increase in ammonium nitrate demand.
2.2 AMMONIUM NITRATE PRODUCTS AND USES
Ammonium nitrate (AN) is formed by reacting ammonia and nitric acid
to produce an 83 percent aqueous ammonium nitrate solution. This solution
may be sold for use as a fertilizer, or may be further concentrated to
form a 95-99.5 percent ammonium nitrate melt for use in solids formation
processes. Solid ammonium nitrate may be produced by prilling, graining,
granulation or crystallization. In addition, prills can be produced in
either high or low density form, depending on the concentration of the
melt. High density prills, granules and crystals are used as fertilizer.
Ammonium nitrate grains are used solely in explosives. Low density
prills can be used as fertilizer or in explosives.
In 1979, 77 percent of all ammonium nitrate produced (both solution
and solid) was used as fertilizer.3 In 1980, it is estimated that the
ammonium nitrate industry will have a final product yield of 5.31 Tg
(5,840,000 tons) of solids and 4.77 Tg (5,250,000 tons) of AN solution.2
Table 2-3 presents the number of plants and their total production
capacity by the type of solid ammonium nitrate they produce. As can be
seen from Table 2-3, prilling plants now represent the bulk of the solid
producing capacity.
Prior to World War II, graining was the primary method of solids
production. Then low density prills replaced grains in the explosives
market and high density prills were used in the fertilizer market. So
after the war, most new installations were designed to produce prills.
Since 1960 another trend has developed; granules have started making
2-4
-------
TABLE 2-2. AMMONIUM NITRATE PRODUCTION, CAPACITY, AND
CAPACITY UTILIZATION RATES2
Year
1361
1362
1363
1964
1965
1965
1967
1363
1969
1370
1371
1372
1373
1974
1975
1976
1377
1373
1379
Production
(103 Mg)
2,383
2,981
3,335
3,367
4,203
4,467
5T137
5,443
5,089
5,541
6,025
6,154
6,251
5,549
6,771
5,353
5,771
5,545
7,074
Capacity
(10* Mg)
4,017
4,239
4,720
5,377
6,013
7,071
7,617
7,804
8,157
8,025
8,124
7,S88
7,843
7,637
7,395
8,250
8,317
8,473
9,315
Capacity
utilization
(percent)
71. 7700
70.3232
70.5780
71. 9174
69.8986
63.1735
67.4412
69.8104
62. 3881
70.2923
74.1630
78. 1440
79.7015
87.0630
84.6904
77.0061
81.4115
78.3793
75. 9420
2-5
-------
TABLE 2-3. NUMBER OF PLANTS BY TYPE OF SOLID PRODUCED
AND CAPACITY, 1980 2
Product
Number of
plants
Estimated
production capacity
(103 Mg)
Prills
Low density
High density
Low and high density
Total prilling
10
12
_7
29
1,276
1,396
1,880
4,552
Granules
611
Grains
37
Crystals
Total Solid
J_
38
14
5,314
2-6
-------
inroads into the high density prill market. This is partly due to the
fact that granules have more abrasion resistance and a higher crushing
strength than prills.
Within the United States, ammonium nitrate competes with a number
of other nitrogenous fertilizers. The major competitors are anhydrous
ammonia, aqueous ammonia, nitrogen solutions, urea and ammonium sulfate.
Since 1974, the demand for ammonium nitrate fertilizers has been decreasing,
particularly for solid ammonium nitrate fertilizers. In 1979, ammonium
nitrate accounted for 11 percent of all nitrogen consumed in the United
4
States as fertilizer. The increasing use of urea fertilizer is one
reason for the decline. However, in contrast to the decreasing demand
for solid ammonium nitrate fertilizers, ammonium nitrate explosives
3
demand has risen steadily. Currently there are no economically viable
alternatives to ammonium nitrate for use in explosives.
2-7
-------
2.3 REFERENCES
1. Bridges, J.D. Fertilizer Trends 1979. Bulletin No. Y-150.
Muscle Shoals, Alabama, TVA National Fertilizer Development Center.
January 1980. pp. 41-42.
2. Memo from Ramachandran, V., Research Triangle Institute, to Rader, R.,
Radian Corporation. January 6, 1981. 6 p. Information about data
stored in Triangle University Computing Center.
3. Reference 1, p. 14.
4. Reference 1, p. 12.
2-8
-------
3.0 PROCESSES AND THEIR EMISSIONS
3.1 INTRODUCTION
This chapter describes uncontrolled emissions from the ammonium
nitrate (AN) processing industry. Section 3.1 presents the basic AN
process chemistry, a manufacturing overview and an emissions overview.
Section 3.2 describes each process and presents its emissions.
3.1.1 Process Chemistry
Ammonium nitrate is produced as an aqueous solution by the neutralization
of nitric acid with ammonia.\ The reaction is represented by the equation:
HN03(aq) + NH3(g) * NH4N03(aq) + heat
Typically, a 56 to 60 weight percent nitric acid solution is mixed with
gaseous ammonia in a ratio ranging from 3.55-3.71 to 1 by weight. This
feed rat i p prod u c es_an_ 83. weig ht^percenl_ ammonium nit rate product. The
reaction is an acid-base neutralization which liberates 46.5 to 52.4 MJ
(44 to 50 thousand Btu's) of heat per mole of ammonium nitrate formed,
depending on the concentration of the nitric acid feed. This reaction
is typically carried out at atmospheric pressure, with the temperature
between 405 and 422 K (270-300°F).)
Rosser et al. reports that ammonium nitrate can decompose or disso-
ciate as described by the following reactions:
decomposition NH4N03 (1) *• N20(g) + 2H20(g) + heat
dissociation NH4N03 (1)-* » NH3(g) + HN03(g) - heat
Decomposition, an irreversible reaction, is small at temperatures below
505 K (450°F). Dissociation of ammonium nitrate, which is reversible,
is favored by increasing temperatures because it is an endothermic
3-1
-------
reaction. The dissociation reaction is responsible for ammonium nitrate
fume, a significant contributor to emissions during solids formation, as
discussed in Section 3.2.
Ammonium nitrate also alters its crystalline state at various temperatures.
Table 3-1 shows that ammonium nitrate typically passes through four
crystalline states after becoming solid at 443.6 K (339°F). Rapid
transitions between the various crystalline states can result in fracturing
of the AN particles, which leads to AN dust emissions.
TABLE 3-1. PROPERTIES OF SOLID AMMONIUM NITRATE2
Melting Point — 443.6 K (339°F)
Solubility,
@ 273 K ( 32°F)
@ 373 K (212°F)
Crystal States
I
II
III
IV
V
- 118 g/100 g water
- 843 g/100 g water
Temperature, K (°F)
443 to 398 (338 to 257)
398 to 357 (257 to 183.2)
357 to 305 (183 to 89.6)
305 to 255 (89.6 to -0.4)
below 255 (below -0.4)
Morphology
e cubic
6 tetragonal
Y rhombic
3 rhombic
a tetragonal
3.1.2 Process Overview
The process for manufacturing ammonium nitrate (AN) contains up to
seven major unit operations./ The basic arrangement of these operations
is shown in Figure 3-1.1 These major operating steps are:
(1)
(2)
(3)
(4)
(5)
(6)
Solution formation or synthesis
Solution concentration
Solids formation
Solids finishing
Solids screening
Solids coating
(7) Bagging and/or bulk shipping
3-2
-------
ADDITIVE*
CO
I
10
AMMONI > —
SOLIDS
COATING
BAGGING
BULK
SHIPPING
• ADDITIVE MAY BE ADDED BEFORE, DURING OR AFTER CONCENTRATION
b MAY BE BEFORE OR AFTER SOLIDS FINISHING.
Figure 3-1. Ammonium nitrate processing steps,
-------
( The number of operating steps employed is determined by the desired
end product. Plants producing AN solutions alone utilize only the first
and seventh unit operations, solution formation and bulk shipping.)
Facilities producing solid AN can employ all of these operations./
All AN plants produce an aqueous AN solution (Step 1) by reacting
ammonia and nitric acid in a neutralizer to yield an 83 percent aqueous
AN solution. The solution can be sold as a liquid nitrogen fertilizers
or can be further concentrated to make solid AN. The ammonium nitrate
solution is concentrated in an evaporator or concentrator using heat to
drive off additional water (Step 2).^ A melt containing from 95 to 99.8
percent AN at approximately 422 K (300 °F) is produced. The melt is
then used to make solid AN product.)
iOf the various processes used to produce solid AN (Step 3), prilling
and granulation are the most commonl Figures 3-2, 3-3, and 3-4 are flow
diagrams of ammonium nitrate high density prilling, low density prilling,
and rotary drum and pan granulation plants, respectively.
\To produce prills, concentrated AN melt is sprayed into a prill
towerV Ammonium nitrate droplets form in the tower and fall countercurrent
to a rising air stream that cools and solidifies the falling droplets
into spherical "prills". Prill density can be varied by using different
concentrations of ammonium nitrate melt. Low density prills are formed
from a 95 to 97.5 percent ammonium nitrate melt; high density prills are
formed from a 99.5 to 99.8 percent melt. High density prills are less
porous than low density prills./
{j.r\ the prilling process, many manufacturers inject an additive in
the melt stream. Magnesium nitrate or magnesium oxide, for example, is
added to the melt stream at a rate that results in 1 to 2.5 weight
percent of additive in the final product. This additive serves three
purposes: it raises the crystalline transition temperature of the solid
final product; it acts as a desiccant, drawing water into the final
product prills to reduce caking; and it allows prilling to be conducted
3
at a lower temperature by reducing the freezing point of molten AN.
3-4
-------
ADDITIVE'
AMMONIA '1 *.
NITRIC 1
ACID C ^
SOLUTION
FORMATION
OJ
1 'OrTIONAL
tn
1
1
SOI IDS
CONCENTRATION
1
___ I
COATING'
STORAGE
— ••
BAGGING
BULK
SHIPPING
Figure 3-2. High density ammonium nitrate prilling process flow diagram.
-------
ADDITIVE'
AMMONIA
NITRIC
ACID
to
O1
SOLUTION
CONCENTRATION
•OPTIONAL
Figure 3-3. Low density ammonium nitrate prilling process flow diagram.
-------
ADDITIVE
AMMONIA -
NITRIC
ACID
SOLUTION
FORMATION
1
1
SOLUTION
CONCENTRATION
r*
GRANULATION
CO
I
^OPTIONAL
UNDERSIDE RECYCt E
Figure 3-4. Drum granulation or pan granulation process flow diagram.
-------
Rotary drum granulators produce granules by spraying a concentrated
AN melt (99.0 to 99.8 percent AN) onto small seed particles in a long
rotating cylindrical drum. As the seed particles rotate in the drum,
successive layers of AN are added to the particles, forming granules.
Granules are removed from the granulator and screened; offsize granules
are crushed and recycled to the granulator to supply additional seed
particles or dissolved and returned to the solution process.
Pan granulators operate on the same principle as drum granulators,
producing a solid product with similar physical characteristics. However,
in the pan granulation process solids are formed in a large, rotating
circular pan.)
Sandvik belts and graining kettles are less popular solids forming
process equipment. The solids they produce are softer and smaller than
granules from a rotary drum granulator and are used in the production of
packed explosives. Graining kettles are expected to decline in the
4 5
future because they are costly and generally more hazardous to operate. '
^he temperature of the AN product exiting the solids formation
process is approximately 339-397 K (150-255°F). Rotary drum or fluidized
bed coolers prevent deterioration and agglomeration by cooling the
solids prior to storage and shipping. Low density prills, which have a
high moisture content because of a lower melt concentration, require
drying before cooling., They are usually dried in two stages, predrying
and drying. Rotary drum or fluidized bed predryers and dryers are used
for dryingX Predryers, dryers and coolers are referred to as finishing
equipment in this report (Step 4).
(The solids are produced in a wide variety of sizes and must be
screened to produce consistently sized prills or granules. Cooled
prills are screened and offsize prills are dissolved and recycled to the
solution concentration process. Granules are screened prior to cooling.
Any undersize particles are returned directly to the granulator; oversize
particles may either be crushed and returned to the granulator or sent
to the solution concentration process (Step 5)/1
3-8
-------
/Following screening, products can be coated in a rotary drum
coater (Step 6) to prevent agglomeration during storage and shipment.
The most common coating materials are clays and diatomaceous earth.
However, the use of additives in the AN melt may preclude the use of
coatings, j
fSolid AN is stored and shipped either in bulk or in bags (Step 7).
Approximately 10 percent of solid AN produced in the U. S. is bagged. \
3.1.3 Emissions Overview /
(Ammonium nitrate production processes can emit particulates (NH.NCU,
\ \
and coating materials), ammonia and nitric acid. ) Table 3-2 summarizes
EPA test data on uncontrolled emissions from AN production processes.
fParticulate emissions, consisting primarily of AN, are emitted from
neutralizers, evaporator/concentrators, prilling towers, granulators and
solids finishing and handling operations A EPA tests show that ammonium
nitrate emissions from individual sources/range from 0.03 to 147.2 g/kg
(0.06 to 294.6 Ib/ton) of ammonium nitrate produced.
.Ammonia can be emitted from neutralizes, evaporators/concentrators,
prilling towers and granulators. These ammonia emissions, according to
EPA tests, range from 0.03 to 29.7 g/kg (0.05 to 59.5 Ib/ton) of ammonium
nitrate produced.^)
When operating under acidic conditions, neutralizers can emit
nitric acid. EPA has not tested for nitric acid emissions from AN
plants but two plants (Plants M and T) have reported emissions of 0.004
g/kg (0.009 Ib/ton) and 0.08 g/kg (0.16 Ib/ton) of ammonium nitrate
produced, respectively.
3.2 DESCRIPTION OF PROCESSES AND EMISSIONS
This section will give an in-depth description of each process and
its emissions. A detailed analysis of the process operating parameters,
particulate emrissions and factors that affect these emissions are presented
for the solids formation and solids finishing operations. Particulate
emissions frora solution formation, screening, coating, handling and
bagging operations are discussed in this chapter but are not discussed
3-9
-------
TABLE 3-2. EPA TEST DATA ON UNCONTROLLED EMISSIONS FROM
SOURCES IN THE AMMONIUM NITRATE INDUSTRY8
u>
H-'
o
Emission Source
Solution formation
neutrallzer
f-vapora tors/concentrators
Solids formation
low density prill tower
high density prill tower
drum granulator
pan granulator
Solids finishing
LD predryer
LO dryer
LD cooler
IK) cooler
Rotary drum granulator cooler
Pan granulator precooler
Pan granulator cooler
Emission
Ammonium Nitrate9
Part icul ate
g/kg (Ib/ton)
2.6
(5.3)
0.03-0.07 (0.06-0.14)
0.39
1.6
147.2
1.34
10.1-37.3
11.4-93.7 |
12.3-37.8
0.83
7.5-8.6
18
0.25
(0.78)
(3.2)
(294.6)
(2.68)
20.2-74.6)
22.8-187.4)
24.5-75.7)
(1.66)
(15-17.3)
(36)
(0.49)
Constituents
Ammonia
g/kg (Ib/ton)
18.0 (36.0)c
0.066-4.2 (0.13-8.3)
0.13 (0.26)
28.6 (57.2)
29.7 (59.5)
0.07 (0.15)
0-0.29 0-0.58)
0-1.3 0-2.6)
0-0.29 0-0.58)
0-0.03 0.05)
0-1.2 (0-2.3)
0 0
0 0
g (Ib) Amnonlum Nitrate Emitted
kg (ton) Ammonium Nitrate Produced
g (Ib) Excess Ammonia Emitted
kg (ton) Ammonium Nitrate Produced
°Neutra11zer operating with excess NH,.
-------
afterward. Ammonia and nitric acid emissions are also presented in this
chapter; but they also are not discussed further in this document.
3.2.1 Neutralization
The reaction between nitric acid and ammonia, an exothermic acid-
base neutralization, is carried out in a reactor or neutralizer. A 55
percent nitric acid stream is used in the reaction to produce a 61
percent ammonium nitrate solution. The heat generated in this reaction
is used to drive off a portion of the remaining water, further concentrating
the solution to 83 percent ammonium nitrate. The reactor, where neutrali-
zation is actually accomplished, can be a one or two-stage unit. In a
two-stage operation an excess of nitric acid is fed to the first stage
reactor. The reaction products from the first stage flow to a second
reactor where additional ammonia is introduced to insure that all of the
q
nitric acid reacts.
A single-stage reactor (Figure 3-5) may operate with excess ammonia
(NH,), excess nitric acid (UNO,) or under neutral concentrations. Most
plants today operate the neutralizer with excess ammonia. Reactors are
operated under pressure, at atmospheric pressure or under a vacuum.
There are several types of single-stage neutralizers used in the industry;
these include thermosyphon, forced circulation, tank type units and a
propr/ietary system developed by Mississippi Chemical Company.
Emissions occur when steam is liberated during the course of the
exothermic neutralization reaction. Emissions of ammonium nitrate and
ammonia or nitric acid occur as this steam is vented from the neutralizer
vesseu. Ammonia emissions are a result of excess ammonia in the neutrali-
zation and nitric acid emission are a result of excess_nitric acid. EPA
test results of an atmospheric neutralizer operating under excess ammonia
are reported in Table 3-2. The ammonium nitrate emissions were measured
to be 2.6 g/kg (5.3 Ib/ton) of ammonium nitrate produced. Testing
details can be found in Appendix A.
3.2.2 Evaporation/Concentration
The 83 percent AN solution produced in the neutralizer is concentrated
further by heating the solution in an evaporator. This step yields a
3-11
-------
CHEMICAL
STEAM
MIST .
ELIMINATOR
UREA OFF-GAS Mil
(OPTIONAL) '
VAPORIZED
NHj
FtfcD
HHOj
FEED
NH-
HNO.
NEUTRAL12ER
•*• 83% AN TO
PROCESS
TANK
WEAK
LIQUOR
RECYCLE
(OPTIONAL)
Figure 3-5. Single stage neutralizer.
3-12
-------
95 to 97.5 percent melt for low density production or a 99.5+ percent
melt for high density prill production and granulation. Concentrators
employed in the AN industry usually operate at atmospheric pressure,
with a temperature of approximately 423 K (302°F). However, some concentrators
operate under vacuum. Plants producing high density prills or granules
use either single or double stage evaporation, while plants producing
low density prills typically utilize single-stage evaporation.
The air swept falling film evaporator predominates in facilities
that employ only single-stage evaporation (Figure 3-6). Plants using
double stage evaporation employ many different evaporator types, including
forced circulation evaporators, thermosyphon evaporators, calandrias,
air swept falling film evaporators and vacuum falling film units.
Usually air is used to convey evaporated moisture out of these units.
Emissions of ammonium nitrate, and ammonia or nitric acid occur as
the steam and air are vented from the evaporator. Emissions from EPA
tested evaporators are reported in Table 3-2. Ammonium nitrate emissions
of 0.03 to 0.07 g/kg (0.06 to 0.14 Ib/ton) of ammonium nitrate produced
were measured. Details of the testing are included in Appendix A.
3.2.3 Prilling
Prilling involves spraying molten ammonium nitrate from the top of
a prill tower into a countercurrent stream of air. The spray produces
droplets which cool and solidify into prills as they fall. Figure 3-7
is a generalized flow diagram of the prilling operation. Hot ammonium
nitrate melt from the concentrators or from storage is delivered to a
head tank at the top of the prill tower. The head tank may have a
return line to the feed tank to allow liquid level control. The ammonium
nitrate melt flows from the head tank to a spray device which forms
droplets that fall through the prill tower. As they cool, the droplets
form prills.
Two spray devices are employed in the industry, spray plates or
heads (Figure 3-8), and spinning buckets (Figure 3-9). Spray plates are
the most common. A stream or jet of AN melt is produced as the melt is
3-13
-------
AIR AND
WATER VAPOR
UNDERFLOW
WEI
WEAK
AN SOLUTION
AIR SWEPT
FALLING FILM
EVAPORATOR
PACKED
SECTION
(OPTIONAL)
ENTRAINMENT
SEPARATOR
FEED
DISTRIBUTORS
STEAM
BLOWER
"AMBIENT
AIR
CONDENSATE
HEATED
-STEAM
AIR
HEATER
AIR
CONDENSATE
CONCENTRATED
AN SOLUTION
Figure 3-6. Air swept falling film evaporator,.
3-14
-------
i-
CD
O
c
i-
s_
Q.
-------
HEADTANK
CONTAINING
MELT
MULTIPLE
SPRAY HEADS
Figure 3-8. Multiple spray plate or nozzle arrangement.
3-16
-------
MELT FROM
HEAOTAMK
PERFORATED
BUCKET
ROTATION
' BUCKET MAY BE CONICAL SHAPE
HEADTANK
SPINNING
BUCKET
PRILL
TOWER
Figure 3-9. Spinning bucket.
3-17
-------
forced through orifices in the spray plate. Spinning buckets produce an
AN melt stream by centrifugally forcing the AN melt through orifices.
The stream produced by either device breaks up into discrete droplets as
it falls through the tower.
Tables 3-3 and 3-4 summarize available information on high and low
density prill towers, respectively. Prill towers can have a square,
rectangular, multi-sided or circular cross-section. The airflow required
for cooling the prills determines the prill tower cross-section. Airflow
through the tower must be great enough to sufficiently cool and solidify
the droplets, but not so large as to produce an air velocity that would
cause excessive entrainment of AN particulate. Historically, prill
towers have been designed for air velocities of about 2 meters/sec (6
ft/sec). Prill tower height and the airflow necessary for cooling the
prills are interdependent. A taller prill tower requires less airflow
because the greater fall distance provides the required air contact for
proper cooling.
The actual cooling process involves removing both the latent heat
of fusion and the sensible heat of the prills as they solidify. This
heat is removed by contact with air in the prill tower. Airflow through
the tower can be produced by several fan arrangements: fans exhausting
out of the top of the tower (induced flow), fans forcing air into the
bottom of the tower (forced flow), or fans located at both the top and
bottom of the tower (balanced flow). Solid prills are colle'cted at the
tower bottom and belt conveyed to subsequent prill finishing equipment.
I Prill tower emissions result from the carryover of fine particles
and fume by the air exiting the tower. Fine particles originate from
the formation of prills and prill breakup. As prills form they are
accompanied by smaller microprills which can be entrained in the exhaust
air stream. Prill breakup can occur due to attrition as they collide
with the walls of the tower, as they are collected at the, bottom of the
tower, or from a rapid transition between crystal states.] Fur.iing results
from the dissociation of ammonium nitrate and is directly proportional
3-18
-------
TABLE 3-3. AMMONIUM NITRATE PRILL TOWER PARAMETERS
(HIGH DENSITY PRILL PRODUCTION)7
OJ
I
Prill Tower
design capacity
Plant Mg/day (Tons/day)
A 567
G 544
Ha
I " 838C
M 363
N 998
N 363
P 680
T 717
(625)
(600)
--
(922)c
(400)
(1,100)
(400)
(750)
(790)
Tower
cross-sectional
~area ,
meters* (feet^)
42
41
83.6
33.4
31.2
58.1
37.2
45
298.9
(452)
(441)
(900)
(360)
(336)
(625)
(400)
(484)
(3,217)
Tower Tower
Tower height ^airflow (actual) air velocity
Meters (feet) m /m1n (cfm) Meters/s (fps)
46. 9b
(154)
24. 4b
(80)
51. 8b
(170)
67.1
(220)
29.9
(98)
61
(200)
36.6
(120)
42. 7b
(140)
44.8
(147)
7,219
—
10,336
6,286
3,766
16,254
6,343
4,663
9,061
(254,930) 2.86
—
(365,000) 2.06
(222,000) 3.14
(133,000) 2.01
(574,000) 4.66
(224,000) 2.84
(200,000) 2.10
(320,000) 0.51
(9.40)
--
(6.76)
(10.28)
(6.60)
(15,31)
(9.33)
(6.89)
(0.166)
Pressure head
Droplet at droplet
formation device
technique kPa (pslg)
Multiple spray
plates
Single spray 5
plate (1
—
Single spray
plate
Multiple spray
plates
--
—
Single spray
plate
Spinning bucket
•-
.98-11.96
.06-2.12)
14.94
(2.65)
--
12.55
(2.23)
4.48
(0.795)
4.48
(.795)
—
—
Temperature
AN prills
K (°F)
372
397
358
389
389
372
372
383
364
(210)
(255)
(185)
(240)
(240)
(210)
(210)
(230)
(195)
3Th1s tower can produce both HD and LD prills
Reported as "free fall" height.
cReported as production capacity.
- data shown are for HD prill production.
-------
TABLE 3-4. AMMONIUM NITRATE PRILL TOWER PARAMETERS
(LOW DENSITY PRILL PRODUCTION)11
Plant
C
F
Hb
OJ J
i
o
0
Q
z
Prill Tower
Design Capacity
Mg/day (tons/day)
181
223
525
410
514
273
726
(200)
(245)
(576)
(450)
(564)
(300)
(800)
Tower
Cross-Sectional
-Area ?
Meters^ (feer)
• •
18.2
83.6
18.6
41
65.4
182.3
mm
(196)
(900)
(200)
(441)
(704)
(1962)
Tower Tower
Tower Height Airflow (Actual) Air Velocity
Meters (feet) nvVmln (cfm) Meters/s (fps)
**
42.7d
(140)
51. 8d
(170)
36. 6d
(120)
-_
54.9
(180)
67.07
(220)
• •
1,699
8,673
2,832
4,248
5,437
7,796
• «
(60,000)
(305,000)
(100,000)
(150,000)
(192,000)
(275,320)
mm
1.56
1.72
2.54
1.73
1.39
0.71
• «
(5.10)
(5.65)
(8.33)
(5.67)
(4.55)
(2.34)
Droplet atSDropleta Temperature
Formation Device AN prills
Technique kPa (pslg) K (°F)
Multiple spray
head
Single spray
head
..
Multiple spray
head
Single spray
head
Multiple spray
plates
Spinning bucket
14.94C
(2.65)
<•*•
fc —
17.93
(3.18)
.-
11.96C
(2.12)
_.
• «•
355
350
366
366
350
~_
•••
(180)
(170)
(200)
(200)
(170)
_M
Data not available.
This tower can produce both HD and LD prills-data shown are for LD production.
^Maximum.
Reported as "free fall" height.
-------
to melt temperature. The fume may recombine upon exiting the tower to
12
form sub-micron AN crystals.
(Pa
(Particulate emission rates from prill towers may be affected by the
following parameters:
(1) Tower airflow
(2) Spray melt temperature
(3) Condition of spray device orifices and type of spray device
(4) Ambient air temperature
(5) Crystal state changes of solid prills
The effect of these parameters on emissions are discussed in the following
paragraphs.
\ Tower airflow affects emissions because it determines the air
velocity in the tower. Increasing tower airflow increases tower velocity
thus increasing entrainment of particles} Prill tower emissions may be
very sensitive to tower velocity. For example, one study reports that a
change in velocity from 1 m/sec to 3 m/sec increases emissions by a
factor of 14.13
Melt temperature is another significant factor that affects emissions.
As the temperature increases, vapor pressure increases, with a corresponding
increase in the amount of fume generated. YThe spray melt temperature
depends on specific plant operating practice and whether the product is
low or high density prills^N Tables 3-5 and 3-6 summarize melt conditions
for low and high density production. ( On the average, the melt spray in
V v
high density towers is 24 K (45°F) hotter than low density spray melt.j
Therefore, it is expected that fume emissions would be greater in high
density towers than low density towers.)
The condition of the orifices in the spray device can also affect
emissions. Orifices should be round and clean to produce round, correctly
sized prills. If a hole is partially plugged it can produce prills that
are too small, called micro-prills; but more often it will spray in a
manner that produces only fine dust. These fines can be entrained by
the tower airstream and increase particulate emissions. Furthermore, if
a hole is partially plugged so that it sprays at an angle, the sprays
3-21
-------
TABLE 3-5. MELT STREAM CHARACTERISTICS FOR LOW DENSITY PRILL PRODUCTION
14
Plant
C
F
H
J
0
Q
Average
NA-Not Ava
TABLE 3-6.
Percent by Weight
Temperature Ammonium Nitrate % H^O
NA
422 K (300°F)
425 K (305°F)
439 K (330°F)
430 K (315°F)
416 K (290°F)
426 K (305°F)
ilable
MELT STREAM CHARACTERISTICS
95.0
96.5
96.5
97.0
96.0
96.0
96.2
FOR HIGH DENSITY
5.0
3.5
3.5
3.0
4.0
4.0
3.8
PRILL PRODUCTION14
Plant
A
G
H
I
M
N
N
T
Average
Temperature
450 K (350°F)
450 K (350°F)
453 K (356°F)
450 K (350°F)
455 K (360°F)
455 K (360°F)
458 K (365°F)
458 K (365°F)
450 K (350°F)
% AN3
98.4
97.7
97.7
99.0
99.8
99.9
99.9
99.0
98.9
%H203
0.5
0.3
0.2
0.5
0.2
0.1
0.1
0.2
0.3
Does not sum to 100 percent because of the use of additives.
3-22
-------
may impinge on one another, creating fine droplets which form ammonium
nitrate dust and increase emissions. Spinning buckets tend to have
fewer problems with orifice plugging than spray plates.) However, spray
plates can be vibrated to aid droplet formation and decrease micro-prill
formation.
t<
Ambient air is used to cool prills. Changes in ambient temperature
affect operation and production parameters, which may affect prill tower
emissions. As the air temperature increases, a greater airflow is
required to cool the prills. The required summer airflow rate is approximately
40 percent greater than the airflow used during winter operation. If
the airflow rate must be increased because of ambient conditions, emissions
will increase due to increased entrainment of mi crop rills} Higher
ambient air temperatures also cause AN fuming to increase because cooling
is slower at the prill surface.
Emissions are also affected by the transition of the prills between
crystal states. A rapid transition in crystal state can cause the prill
to disintegrate. The resulting dust can become entrained in the prill
tower airflow, thus increasing emissions. Low density prills are more
sensitive to crystal changes than high density prills, and have a greater
tendency to break up into dust because of their larger void spacing.
Emissions data on high and low density prill towers from EPA and
industry tests are reported in Table 3-7. Uncontrolled ammonium nitrate
emissions from high density prill towers range from 0.81 to 2.74 g/kg
(1.63 to 5.48 Ib/ton) of AN produced. Industry and EPA test data on
emission quantities indicate that uncontrolled ammonium nitrate emissions
from low density prill towers range from 0.21 to 0.69 g/kg (0.42 to 1.38
Ib/ton) of AN produced. However, industry and EPA data may not be
directly comparable because of differences in sampling and analytical
procedures.
3.2.4 Granulation
3.2.4.1 Drum Granulation. The drum granulator consists of a
rotating horizontal cylinder, either 3.7 or 4.3 m (12 or 14 ft) in
diameter, which is divided by a retaining dam into two sections, the
3-23
-------
TABLE 3-7. UNCONTROLLED EMISSIONS FROM PRILL TOWERS
a,17
Plant
Ab
G
H
I
0
P
C
J
L
V
w
X
zb
aResults
unless
bResults
Cg Ob)
Product
High Density
Prills
High Density
Prills
High Density
Prills
High Density
Prills
High Density
Prills
High Density
Prills
Low Density
Prills
Low Density
Prills
Low Density
Prills
Low Density
Prills
Low Density
Prills
Low Density
Prills
Low Density
Prills
Ammonium Nitrate0
gAg
1.60
2.74
1.16
1.28
0.81
1.93
0.21
0.22
0.69
0.60
0.47
0.49
0.39
of emissions characterization studies
otherwise noted 'Industry
of a test conducted by EPA
Ammoni urn Ni trate Emi tted
data).
as part of
(Ib/ton)
(3.20)
(5.48)
(2.33)
(2.55)
(1.63)
(3.86)
(0.42)
(0.45)
(1.38)
(1.20)
(0.93)
(0.98)
(0.78)
conducted by
this study.
Ammonia
g/kg (Ib/ton)
28.6 (57.2)
_ _
M _
w _
_ _
_ _
_ _
_ _
_ _
_ _
_ -
_ _
0.1-3 (0.26)
plant personnel
kg (ton) Ammonium Nitrate Produced
dg (ib)
Ammonia Emitted
kg (ton) Ammonium Nitrate Produced
3-24
-------
granulating section and the cooling section (Figure 3-10). A pipe
running axially near the center of the granulating section emits a fine
spray of ammonium nitrate melt, typically at a concentration of 99+
18
percent by weight and at a temperature of 458 K (365°F). Ammonium
nitrate seed particles (from offsize product recycle) enter the drum at
the granulation end. As the drum rotates, lifting flights in the granulating
section pick up the ammonium nitrate seed particles and shower these
particles down through the AN melt spray. As the particles pass through
the spray, they are coated with molten AN, which cools and hardens on
the particles as the lifting flights carry them away from the spray.
The particles are showered back down through the spray again coating
them with molten AN. This process is repeated; gradually the particles
build up to product size through the addition of successive layers of
AN. This method of formation gives the granule an onion-skin-like
(concentrically layered) structure.
Granulators require less air for operation than prill towers. The
air entering the granulator is generally chilled to about 283 K (50°F)
and cools the granules to approximately 308 K (95°F) by the time they
l fi
leave the cooling section of the drum. The countercurrent airflow
removes the heat of crystallization of the ammonium nitrate and entrains
on
10 to 20 percent by weight of the product. The desired product is
achieved by controlling the residence time of the particle in the drum.
Particles in the bed tend to segregate according to size; the
smaller granules of ammonium nitrate settle down to the bottom to be
picked up by lifting flights. The drum operates at a slight angle, so
material migrates by gravity towards the cooling section. The larger
particles at the top of the bed pass over the retaining dam into the
cooling section. After passing through the cooling section, the granules
exit the rotary drum and are screened. Undersized particles are separated
and recycled as seed material, while oversize granules are either crushed
and recycled as seed, dissolved and added to the solution process, or
both. The recycle to product ratio for a drum granulator is typically
2:1.20
3-25
-------
SEED
AMMONIUM
NITRATE
PARTICLES
ROTATING
DRUM
AMMONIUM
NITRATE
SPRAY
CO
i
ro
en
EXHAUST AIR
TO SCRUBBER
CONCENTRATED
AMMONIUM
NITRATE
SOLUTION
RETAINING
DAM
BED OF AMMONIUM
NITRATE GRANULES
LIFTING FLIGHTS
COOLING
AIR
PRODUCT
Figure 3-10. Rotary drum granulator.
-------
u
The granulation process can produce larger particles with greater
abrasion resistance and about twice the crushing strength of standard
21N
prills, but their product is not as spherical or smooth as prills.
However, any range of product sizes, from smaller fertilizer grade
granules to extra large forestry grade, can be manufactured in granulators.
Different sizes are produced by varying the height of the retaining dam
in the granulator, decreasing the contact time of the seed particles in
the drum, choosing suitable screen sizes, or by using a combination of
the above. A major disadvantage of granulators is that low density
ammonium nitrate product cannot be manufactured economically using
op
present technology. A survey of industry indicated that there are six
drum granulators operating at five different plants in the United States.
All of these granulators are of the same design and operation.
Emission rates from drum granulators may be affected by the following:
(1) Number, design and location of lifting flights
(2) Airflow rates through the drum
(3) Recycle rate of seed material
(4) Rotation rate of the drum
(5) Crystal state changes of granules
The number, design and location of the lifting flights directly
affect the emission rate. Flights lift and drop granules through the
moving air stream to provide cooling of the particles; fine particles
tend to become entrained in the air stream leaving the granulator. To
reduce the entrainment of particles, some modifications have been made
to existing drum granulators. These modifications involved changing the
size and/or shape of the lifting flights or removing the lifting flights
nearest the air discharge end of the granulator. These modifications are
?3
also being made on new installations.
An increase in the airflow rate through the drum causes greater
entrainment of small particles and increases emissions. An airflow
velocity of approximately 1.2 meters/sec (4.0 ft/sec) appears to represent
24
an optimum balance between cooling requirements and product loss.
3-27
-------
[he recycle rate of seed material affects the bed temperature, and
therefore, can affect emissions.) Only a relatively narrow bed temperature
ranae can be tolerated.} An increase in seed material recycle rate will
25
cool the bed, while a decrease will raise the bed temperature. If
the bed temperature increases significantly, and is maintained for \
several hours, the granules will turn to dust and increase emissions.
An increase in the rotation rate of the drum increases the entrainment
of AN in the airstream. Originally granulators were designed to rotate
at 9 rpm, but because of excessive wear, the rate was reduced to 6 rpm,
?7
with no apparent effect on product quality. However, once a suitable
rotation rate is found, it is normally not changed, thus the rate of
rotation is not considered a process variable.
As with prills, a rapid change in crystal state can cause the
granules to break up into dust. This dust can become entrained in the
airstream, increasing emissions.
Table 3-8 presents uncontrolled emissions from drum granulators.
According to an EPA test, one drum granulator had uncontrolled ammonium
nitrate emissions of 147.2 g/kg (294.6 Ib/ton) of AN produced. The
industry test data presented in Table 3-8 cannot be compared directly to
EPA test data because of differences in sample collection and analysis
procedures. However, the uncontrolled emission factors determined by
industry are in close agreement with EPA's.
3.2.4.2 Pan Granulation. The pan granulator operates on basically
the same principle as the drum granulator; it generates granules by
29
adding successive layers of molten ammonium nitrate to seed particles.
The equipment consists of a large rotating circular pan tilted off the
horizontal. Seed material (from offsize product recycle) deposited near
the top of the pan, along with fine particles carried up by the rotating
pan, pass through a fine spray of essentially anhydrous ammonium nitrate
melt (see Figure 3-11). The newly sprayed particles roll to the bottom
of the pan. As in the drum granulator, the smaller particles in the pan
granulator sift toward the bottom of the granule bed on the lower part
of the pan. Larger granules spill over the edge of the pan onto a
3-28
-------
TABLE 3-8. UNCONTROLLED EMISSIONS FROM GRANULATORS28
Plant
Drum Granulation
Ba
Kb
Kb
Pan Granulation
Da
aEPA test data.
Capaci ty
Mg/day Tons/ day
381 420
249 275
352 388
325 358
Ammonium Nitrate0
Particulate Ammonia
g/kg Ib/ton g/kg Ib/ton
147.2 295 29.7 59.5
152 305
138 277
1.34 2.68 0.07 0.15
Reported by -industry.
q (Ib) Ammonium Nitrate Emitted
kg (ton) Ammonium Nitrate Produced
q (lb) Ammonia
Emitted
kg (ton) Ammonium Nitrate Produced
3-29
-------
SPRAY
AREA COVERED
BY SOLUTION SPRAYS
PAN ROTATION
RECYCLE
ENTERS HERE
LARGE GRANULES
LEAVE PAN HERE
figure 3-11. Top view of pan granulator.
3-30
-------
conveyor belt and are removed for further processing. The pan granulator
yields a product which is less spherical and somewhat softer than granules
produced in a rotary drum. Pan granulation also tends to have a
larger recycle to product ratio than drum granulators because almost all
the required bed cooling is accomplished by the cooled recycle particles.
Recycled material consists of undersized and oversized granules.
Undersized granules are used as seed particles and the oversized material
is either dissolved and used in solution formation or crushed and used
as seed. The amount of crushed material used as seed is held to a
minimum since this practice can lead to formation of agglomerates and
weak granules.
Operational parameters which are critical to product quality include
the concentration and temperature of the feed melt, the slope and
rotational speed of the pan, the location of the sprays, and the amount,
size and temperature of the recycle material.
Emissions are affected by the following:
(1) Airflow rates over the pan
(2) Rotational speed of the pan
(3) Bed temperature
(4) AN melt spray
(5) Crystal state changes of granules
An increase in the airflow rate can affect emissions by entraining
more fine particles and fume. However, there is very little airflow
over the pan; consequently, entrainment of fine spray or seed granules
is less than that encountered in drum granulation. Operating data
24
indicate that less than 5 percent by weight of the product is entrained.
The rotational speed of the pan can also affect emissions. A
higher rotational speed increases attrition of the granules, thus increasing
emissions.
The temperature of the bed affects granule temperature. If bed
temperature increases significantly, granules will turn to dust and
increase emissions.
3-31
-------
AN melt spray conditions affect emissions through fuming and fine
particle formation. Fine particles are formed when the spray strikes
the bottom and splatters. This splatter quickly cools to form fine
particles which increase emissions.
As with other solids, a rapid change in crystal state can cause the
granules to break up into dust. This dust can become entrained in the
air stream, increasing emissions.
A detailed discussion of tests conducted by EPA on a pan granulation
facility is presented in Appendix A. Uncontrolled ammonium nitrate
particulate emissions averaged 1.34 g/kg (2.68 Ib/ton) of ammonium
nitrate produced (Table 3-8).
3.2.5 Solids Finishing
The ammonium nitrate industry utilizes various combinations of
solids finishing equipment to cool, dry, screen and coat the ammonium
nitrate solid, depending on the particular solid product and its formation
process. High density prills are cooled, screened and sometimes coated;
low density prills are predryed, dryed, cooled, screened and coated; and
drum granulated product is screened, cooled and may be coated. Pan
granulated product can then either follow the same finishing sequence as
drum granulators, or pass through a precooler after solids formation to
aid in cooling. Tables 3-9, 3-10, and 3-11 present operating parameters
for coolers, predryers and dryers, respectively. The EPA test results
are presented in detail in Appendix A. Process equipment operation and
emissions are discussed below. ,
3.2.5.1 General cooler/dryer equipment designs. ( Cooling and
drying are usually conducted in rotary drumsT^ In the finishing process,
inlet air is either conditioned or introduced at ambient temperatures.
The conditioning process uses heat exchangers to heat, cool, or dehumidify
the air. Moisture removal in the low density prill is one of the most
critical steps in producing the final desired prill. If moisture is not
removed after prill formation, caking will result. With the exception
of an auxiliary air dehumidifier, heater or cooler, all rotary drums
have the same physical configuration. Figure 3-12 presents the configuration
3-32
-------
TABLE 3-9. COOLER OPERATING PARAMETERS32
OJ
Plant
A
H
N
1
N
N
T
B
E
K
K
D
D
C
H
J
L
I
Q
F
Z
Facility
High Density Rotary
Drum Cooler
High Density Rotary
Drum Cooler
High Density Rotary
Drum Cooler
High Density Rotary
Drum Cooler
High Density Rotary
Drum Cooler
High Density
Fluldlzed Bed Cooler
High Density
Fluldtzed Bed Cooler
Rotary Drum Granulator
Rotary Drum Cooler
Rotary Drum Granulator
Rotary Drum Cooler
Rotary Drum Granulator
Rotary Drum Cooler
Rotary Drum Granulator
Fluldtzed Bed Cooler
Pan Granulator
Rotary Drum Precooler
Pan Granulator
Rotary Drum Cooler
Low Density Rotary
Drum Cooler
Low Density Rotary
Drum Cooler
Low Density Rotary
Drum Cooler
Low Density Rotary
Drum Cooler
Low Density Rotary
Drum Cooler
Low Density Rotary
Drum Cooler
Low Density Fluldlzed
Bed Cooler
Low Density Fluldlzed
Bed Cooler
Production Capacity
Mg/day (tons/day)
545 (600)
294 (324)
458 (504)
318 (350)
363 (400)
363 (400)
87Z (960)
454 (500)
277 (305)
272 (300)
363 (400)
320 (353)
314 (346)
194 (214)
457 (504)
453 (499)
409 (451)
409 (451)
272 (300)
222 (245)
582 (641)
Airflow
scm/Hg (scf/ton)
1496 (48.000)
3281 (105.286)
2811 (90,186)
4535 (145,536)
2333 (74,845)
6065 (194,593)
1223 (39,241)
1800 (57,670)
2150 (68,930)
1940 (62.050)
2770 (88,720)
3200 (102,400)
1610 (51,610)
1620 (51.900)
2700 (86,380)
1440 (46,150)
1740 (55,850)
4150 (133,100)
2250 (72,000)
3320 (106,330)
4281 (137.281)
Air Temperature K(°F)
Inlet — CuTTeT
283 (50)
300 (80)
291 (65)
283 (50)
283 (50)
283 (50)
280 (45)
—
.
2B2 (48)
299 (79)
—
.
281 (47)
303 (85)
289 (60)
278 (40)
278 (40) •
294 (70)
291 (65)
-
339 (150)
354 (177)
339 (151)
365 (198)
.
.
294 (70)
—
332 (138)
308 (95)
312 (102)
m
.
328 (130)
317 (111)
316 (110)
316 (110)
316 (110)
325 (125)
308 (95)
-
Solid AN Temperature K(°F)
Inlet
372 (210)
389 (240)
357 (184)
397 (256)
372 (210)
372 (210)
363 (194)
330 (135)
324 (124)
333 (140)
333 (140)
„
•
345 (162)
334 (142)
333 (140)
322 (120)
322 (120)
347 (165)
333 (140)
-
Outlet
313 (105)
316 (110)
331 (137)
311 (100)
305 (90)
305 (90)
324 (124)
307 (93)
300 (81 )
303 (66)
305 (90)
„
-
306 (91)
308 (95)
304 (88)
304 (88)
304 (88)
316 (110)
308 (95)
-
-------
TABLE 3-10. LOW DENSITY PREDRYER OPERATING PARAMETERS3
33
CO
I
CO
Plant
C
Fb
H
J
L
L
Q
Z
Capacity,
Mg/day (TPD)
194
(ZH)
222
(245)
457
(504)
453
(499)
409
(451)
409
(451)
272
(300)
479
(528)
Prill Moisture
Prill Temperature, K (°F) wt percent HpO Prill Residence
Inlet
331
(137)
353
(175)
345
(162)
366
(ZOO)
350
(170)
350
(170)
350
(170)
-
Outlet Inlet Outlet Time, Minutes
350
(170)
344 3.5 2.6 20
(160)
344 2.5 1.5 10
(159)
355 3.0 1.8 20
(180)
366 2.5 1.4 30
(145)
336 2.5 1.4 30
(145)
339 3.5 2.5-3.0 13
(150)
- " "
Air Temperature K (°F)
Inlet
378
(220)
350
(170)
336
(145)
366
(200)
355
(180)
355
(180)
366
(200)
—
Outlet
343
(158)
350
(170)
345
(161)
344
(161)
322
(120)
322
(120)
339
(150)
- —
Air Flow Rate
dscm/Mg (dscf/ton)
1560
(49,840)
3310
(106,000)
2570
(82,380)
1130
(36,060)
1400
(45,000)
1790
(57,450)
2250
(72,000)
3263
(104,649)
3A11 preclryers are rotary drum except as noted.
bF1u1d1zed bed
-------
TABLE 3-11. LOW DENSITY PRILL DRYER OPERATING PARAMETERS9
34
CO
1
CO
en
Plant
C
Fb
II
J
L
L
Q
z
Capac1t>,
Mg/day (TFD)
194
(214)
222
(245)
457
(504)
453
(499)
409
(451)
409
(451)
272
(300)
479
(528)
Prill Temperature, K (°F)
Inlet
350
(170)
344
(160)
344
(159)
355
(180)
336
(145)
335
(145)
339
(150)
-
Outlet
345
(162)
333
(140)
334
(142)
333
(140)
322
(120)
322
(120)
316
(110)
-
Prill Moisture
wt percent H?0 Prill Residence
Inlet Outlet Time, Minutes
.
2.6 1.6 20
1.5 0.3 10
1.8 0.4 20
1.4 0.4 30
1.4 0.4 30
2.8 0.9 13-23
- » * -
Air Temperature K (°F) Air Flow Rate
Inlet
370
(206)
333
(140)
330
(135)
366
(200)
355
(180)
355
(180)
353
(175)
"
Outlet
345
(161)
333
(140)
330
(139)
333
(140)
322
(120)
322
(120)
314
(105)
dscm/Mg (dscf/ton)
1450
(46,410)
3480
(111,300)
; 2800
{(89,600)
< 1080
(34,620)
'. 1990
.(63,830)
4240
(136,000)
2250
;(72,000)
' 2942
(94,324)
*
aA11 dryers are rotary drum except as noted.
bF1u1d1zed bed
-------
COOLER
SHELL
LIFTING
FLIGHTS
SHELL-
SUPPORTING
ROLLERS
END VIEW
AJR
OUTLET
DISCHARGE
FAN
FEED
CHUTE
COOLER
SHELL
CHILLER
AIR
INLET
AIR
DISCHARGE
HOOD
SHELL-SUPPORTING
POOLERS
COOLED SOLIDS
DISCHARGE
SIDE VIEW
Figure 3-12. Rotary drum cooler.
3-36
-------
for a rotary drum cooler. A rotating inclined shell is supported on two
sets of rollers and driven by gear and pinion. At the upper end is the
feed chute which brings in material. Flights, welded along the inside
of the shell, lift the material being dryed or cooled and shower it down
through the flow of air. The product is discharged onto a conveyor at
the lower end of the drum. Just beyond the discharge end of the rotary
drum is a set of heat exchangers which treat incoming air. The airflow,
which is countercurrent to the product flow, is supplied by an induced
draft fan which keeps the system under a slight vacuum. The fan suction
is connected to a hood at the upper end of the drum and the fan discharges
through a stack to the atmosphere or to an emission control device.
Emissions from rotary drum dryers or coolers consist of fine particulates
that have eroded from the product and become entrained in the discharged
air stream.
The following design and process parameters affect emissions from
rotary drum coolers and dryers:
(1) Number, design and location of lifting flights
(2) Speed of drum rotation
(3) Air flowrate through the drum
(4) Temperature of product
Rotary drum dryers, predryers and coolers operate in much the same
manner as the cooling section of drum granulators; therefore, design and
operating parameters affect emissions in similar ways. Both drum rotation
speed and design of the Ijfting jflights jrFfect emissions. As the lifting
flights lift and drop the solids through the moving air stream, fine
particles tend to become entrained in the air stream, creating emissions.
Modifications are often made to the shape, size and location of the
lifting flights in order to reduce emissions. Also, the rotation of
the drum can erode the particles, causing a larger number of fines which
increases emissions. Drum rotation speed is not considered to be a
process variable and is rarely changed once a suitable rate has been
found.
3-37
-------
The airflow rate through the drum affects emissions, also. Higher
airflow rates can increase the amount of fines entrained in the air
stream.
( Prill and granule temperature control is necessary to control
emissions. Changes in specific volume of the solid accompany changes in
crystal structure, which is a function of the solid temperature^ Changes
in specific volume may contribute to solid AN disintegration. With low
density prills especially, the change in specific volume increases
emissions through the creation of additional fines. Also, the bed
temperature in the rotary drum cooler can affect emissions indirectly.
Higher bed temperatures require increased airflow rates to cool the
prills. And, as discussed above, higher airflow rates can cause greater
emissions.
Fluidized bed cooling units are also used on drum granulated and
prilled products. A fluidized bed cooler consists of a long narrow
vessel separated into two parts by a horizontal perforated plate (the
bed plate). Conditioned air is blown up through the bed plate to fluidize
the prills or granules in the upper half of the vessel. Hot prills or
granules drop onto the inclined end of the long plate, and displace the
fluidized particles along the bed causing the cooled material to spill
over the opposite end into the outlet chute, as shown in Figure 3-13.
The advantages of a fluidized bed cooler are that the capital cost,
size, and weight are lower than for a rotary drum; also, no special
foundations are needed and there is no product abrasion on moving parts.
An additional advantage is that the residence time in the unit is much
shorter than for a comparable rotary unit. It is also reported that the
flow of the fluidizing air can be adjusted so that fines are left in the
oc
product or removed for collection and treatment.
Of the two AN plants constructed during the last ten years, both
have employed fluidized bed coolers in their processes. However, there
is insufficient information to conclude that this is an industry trend.
3.2.5.2 High Density Prill Cooling. Because of low moisture
content, high density prills only require cooling when they exit the
3-38
-------
CO
COOL PRILL
OUTLET
COOLING AIR
EXHAUST
PERFORATED
PLATE BED
HOT PRILL
INLET
COOLING AIR
INLET
Figure 3-13. Fluidized bed cooler.
-------
prill tower. The prills are usually belt conveyed from the prill tower,
at temperatures of 358 to 389 K (185 to 240°F), to a rotary drum cooler.
Internal flights in the cooler lift the prills and cause them to fall
through a countercurrent airflow. The prills have a residence time of
8 minutes to approximately 1 hour in the rotary drum cooler depending on
*yj
design. Prills are usually cooled to between 305 and 331 K (90 and
137°F) and have a moisture content between 0.2 and 0.5 percent by
weight (Table 3-9). Airflow rates are reported between 1,496 and
4,535 scm/Mg (48,000 and 145,536 scf/ton) of AN produced. Some plants
report varying the airflow through the cooler to maintain product
outlet temperature at desired levels, while others report varying product
38 39 40
throughput rate to obtain desired product outlet temperature. '^'^
The cooling air gains 50 to 88 K (90 to 160°F) as it passes through the
cooler. EPA emissions data for a high density prill rotary drum
cooler are presented in Table 3-12. The results of EPA testing indicate
that ammonium nitrate is emitted at a rate of 0.8 g/kg (1.6 Ib/ton) of
AN produced.
Fluidized bed coolers are used at two high density prill plants.
Inlet cooling air is reportedly chilled to 280 K (45°F) at one plant and
to about 283 K (50°F) at the other. One of these fluidized bed coolers,
which operates with an airflow of 6065 scm/Mg (194,593 scf/ton) of AN
produced, reportedly lowers prill temperature from 372 K (210°F) to
305 K (90°F). No emissions data are available for these units.
3.2.5.3 Granulated product cooling. Both rotary drum and fluidized
bed coolers are employed to cool granulated ammonium nitrate, but rotary
drums are most commonly used. The units operate identically to coolers
in high density prilling plants.
Emissions data from EPA testing of two drum granulator coolers and
one pan granulator precooler and cooler are presented in Table 3-12.
Ammonium nitrate emissions from the (drum granulator) coolers are
reported to be 7.5 g/kg (15 Ib/ton) and 8.6 g/kg (17.3 Ib/ton) of AN
produced. Ammonium nitrate emissions from the finishing equipment for
the pan granulator were found to be 18.0 g/kg (36.0 Ib/ton) of AN produced
3-40
-------
TABLE 3-12. UNCONTROLLED EMISSIONS FROM COOLERSa
41
Ammonium nitrate
parti culateb Ammonia
Plant Facility g/kg
A High density rotary 0.8
drum cooler
B Rotary drum granulator 7.5
Rotary drum cooler
E Rotary drum granulator 8.6
Rotary drum cooler
D Pan granulator 18.0
Rotary drum precooler
D Pan granulator 0.25
Rotary drum cooler
C Low density rotary 12.3
Drum cooler
L Low density rotary 19.2
Drum cooler
L Low density rotary 35.5
Drum cooler
Z Low density fluidized
Bed cooler 37.8
aAll data is EPA test data unless otherwise noted.
g(lb) Ammonium Nitrate Emitted.
kg(tonj Ammonium Nitrate Produced.
cg(lb) Ammonia Emitted.
(Ib/ton) g/Kg
( 1.6 } 0.02
(15.0 ) 0
(17.3 ) 1.18
(36.0 } 0
( 0.49) 0
(24.5 ) 0
(38.4 )
(70.5 )
(75.7 ) 0.29
(lb/ ton)
( 0.05)
0
( 2.35)
0
0
0
_-
--
( 0.59)
kg(ton) Ammonium Nitrate Produced.
Industry test data.
3-41
-------
for the precooler and 0.25 g/kg (0.49 Ib/ton) of AN produced for the
cooler. A discussion of the testing can be found in Appendix A.
Operating information on three rotary drum coolers and one fluidized
bed cooler is presented in Table 3-9. In rotary drum coolers, the
granule temperature decreases an average of 25 K (46°F). Reported
airflows are 1800 scm/Mg (57,670 scf/ton), 1940 scm/Mg (62,050) and 2150
scm/Mg (68,930 scf/ton) of AN produced. For the fluidized bed cooler,
inlet air is cooled to an average temperature of 299 K (78°F). The
fluidized bed cooler operates with an airflow of 2770 scm/Mg (88,720
scf/ton) of AN produced and lowers the ammonium nitrate granule temperature
from 333 K (140°F) to 305 K (90°F). The temperature of the cooling air
increases approximately 13 K (23°F). Residence time of the granules in
this cooler is approximately one minute.
3.2.5.4 Low density prill predrying, drying, and cooling. Low
density prills initially have a higher water content than high density
prills. To remove this water, low density prills are dried in three
steps: predrying, drying and cooling. Although cooling is not usually
associated with the removal of moisture, ammonium nitrate coolers do
achieve a small amount of final water removal. These steps are normally
conducted in three separate rotary drums, although one plant (Plant F)
reports the use of three separate fluidized beds. Tables 3-9, 3-10 and
3-11 summarize available information on the operation of coolers, predryers,
and dryers, respectively.
Industry reports that the key parameters monitored to control
predryer, dryer or cooler operations are prill temperature and prill
moisture into and out of the units, and air temperature into and out of
the units. ' Plants can control either the airflow rate or the air
temperature to control prill temperature and moisture. Fluidized bed
units generally control airflow rate and rotary drum units generally
control air temperature. *42 The quantitative effect of these parameters
on uncontrolled emissions is not known. However, changes in these and
other parameters can lead to increased emissions, as discussed in Section
3.2.5.1.
3-42
-------
The information in Table 3-10 indicates that between 26 and 44 percent
of the moisture in the prills is removed in the predryer. Residence
time of the prills in the predryer are reported to be between 10 and 30
minutes. The average predryer is fed low density prills at a temperature
of 349 K (169°F) and the prill temperature is reduced to an average of
343 K (158°F) at the exit. Two notable exceptions to the average are
apparent. Plant C reports that the prill temperature increases 19 K
(33°F) in passing through the predryer, and Plant J reports that prills
enter the predryer at 366 K (200°F) and exit the predryer at 355 K
(180°F).
In Table 3-10, reported airflows vary from 1130 to 3310 dscm/Mg
(36,060 to 106,000 dscf/ton) of AN produced for rotary drum predryers.
The airflow rates are varied, depending on the desired product outlet
temperature, inlet air temperature and product throughput rate. Results
of EPA testing indicate that the uncontrolled AN emissions from two low
density rotary drum predryers are 10.1 g/kg (20.2 Ib/ton) and 37.3 g/kg
(74.6 Ib/ton) of AN produced. Results of EPA tests and industry tests
on predryers are presented in Table 3-13.
After predrying, prills are conveyed to a dryer for further drying.
From Table 3-11, it can be seen that between 38 and 80 percent (average
58.5 percent) of the moisture in the entering prills is removed in the
dryer. Residence time is between 10 and 30 minutes. The average dryer
shows a reduction in prill temperature from 343 K (158°F) to 329 K
(133°F). Reported airflows vary from 1080 to 4240 dscm/Mg (34,620 to
136,000 dscf/ton) of AN produced and are varied depending on the desired
product outlet temperature, inlet air temperature and product throughput
rate. Uncontrolled emissions from EPA and industry source tests on low
density rotary drum dryers are presented in Table 3-14. Results of EPA
tests show uncontrolled AN emissions from two low density rotary drum
dryers of 11.4 g/kg (22.8 Ib/ton) and 93.7 g/kg (187.4 Ib/ton) of AN
produced.
After drying, prills are conveyed to a cooler which also removes
some moisture from the prills. Low density prills leaving the cooler
3-43
-------
TABLE 3-13. UNCONTROLLED EMISSIONS .FROM LOW DENSITY
ROTARY DRUM PREDRYERS341
Ammonium Nitrate
particulate" Ammonia
Plant g/kg (Ib/ton) g/kg Ob/ton)
C 10.1 ( 20.2 ) 0 0
Zd 37.3 { 74.6 ) 0.29 (0.58 )
3.2 ( 6.4 )
, e
L2
4.1
(
8.2 )
aAU data is EPA test data unless otherwise noted.
gjlb) Ammonium Nitrate Emitted.
kg (ton) Ammonium Nitrate Produced.
cg(lb) Ammonia Emitted^
kg (ton) Ammonium Nitrate Produced.
Emissions are based on a combined predryer and dryer
the predryer constitutes 22 percent of the emissions by weight.
elndustry test data.
3-44
-------
TABLE 3-14. UNCONTROLLED EMISSIONS FROM LOW
DENSITY ROTARY DRUM DRYERS34'
Plant
C
Zd
L*
L2
Ammonium nitrate
parti culate" Ammonia
g/kg (Ib/ton) g/kg (Ib/ton)
11.4 ( 22.8 ) 0 0
93.7. ( 187.4 ) 1.3 ( 2.6 )
22.9 ( 45.7 )
7.8 ( 15.6 )
aA11 data is EPA test data unless otherwise noted.
g(lb) Ammonium Nitrate Emitted.
kg(ton Ammonium Nitrate Produced.
cq(lb) Ammonia Emitted.
kg (ton)Ammonium Nitrate Produced.
Emissions are based on a combined predryer and dryer outlet of which
the dryer constitutes 88 percent of the emissions by weight.
elndustry test data.
3-45
-------
contain between 0.13 and 0.4 percent (average 0.21 percent) moisture by
weight.45 The average cooler is fed low density prills at 333 K (141°F)
and cools the prills to an average of 307 K (93°F) (Table 3-9). Residence
time in the cooler varies between 10 and 30 minutes. Reported airflows
range between 1440 and 4281 dscm/Mg (46,150 and 137,281 dscf/ton) of AN
produced and are changed depending on the desired product outlet temperature,
inlet air temperature and product throughput rate. Test results on
coolers are presented in Table 3-12. Results of EPA test results show
uncontrolled AN emissions from a low density rotary drum cooler of 12.3
g/kg (24.5 Ib/ton) of AN produced and from a low density fluidized bed
cooler of 37.8 g/kg (75.7 Ib/ton) of AN produced.
3.2.6 Screening
Screening operations separate offsize ammonium nitrate solids from
the properly sized product. In low and high density prilling plants,
offsize material from the screens is redissolved in water or a weak
solution of ammonium nitrate, then recycled to the solution formation
process. In granulation plants, undersized and oversized granules (the
oversized are first crushed) from the screens are returned to the granulator
as seed material or returned to the solution formation process.
Shaking and vibrating screens are most commonly used in the ammonium
nitrate manufacturing industry. Shaking screens consist of a rectangular
frame with perforated plate or wire cloth screening surfaces, usually
suspended by rods or cables and inclined at an angle of about 15 degrees.
Vibrating screens have one or more decks, usually planar. The screen
forms the floor of a box which is vibrated mechanically or electrically.
Thefammonium nitrate particles vibrate normal to the screen surface.
\Emissions are generated by the attrition of the ammonium nitrate
solids against the screens and against one another. Therefore, almost
all screening operations used in the ammonium nitrate manufacturing
industry are enclosed or have a cover over the uppermost screen. The
screening equipment is located inside a building and emissions are
ducted from the process^ Results of the survey conducted during this
program indicate that this operation is a small emission source, and in
most cases no visible emissions were observed.
3-46
-------
3.2.7 Coating and Additives
Solid prills and granules are usually treated to prevent them from
becoming moist and caking. In some cases additives are injected into
the melt for this purpose. Another alternative is to coat the solids
with kaolin, talc or diatomaceous earth. Both additives and coatings
serve a similar purpose. Some plants even utilize both processes when
treating solids. Of thirteen high density prilling plants surveyed,
four plants coat the prills, five plants use both an additive and a
coating, and four plants use an additive. Of seven low density prilling
47
plants surveyed, all report the use of a coating.
A survey of the industry indicates that the type of coating material
affects the final product composition. The final product contains about
0.15 to 1.5 weight percent of coating when using talc, about 1.1 weight
percent when using kaolin, and about 1 to 3 weight percent when using
48
diatomaceous earth.
/ Prills and granules are typically coated in a rotary drum coater.
The rotating action produces a uniformly coated product. The mixing
action also causes some of the coating material to be suspended in air,
thus creating particulate emissions./'' However, drums are typically
maintained at a slight negative pressure and the emissions are vented to
a particulate control device. Any dust captured is usually recycled to
the coating storage bins.^) Industry sources estimate uncontrolled
emissions from the coater to range from 0.5 to 3.0 g/kg (1.0 to 6.0 Ib/ton)
49
of ammonium nitrate produced.
3.2.8 Bagging
Only a small fraction of the total solid ammonium nitrate produced
is bagged (approximately 10 percent)/ Bagging operations are a source
of particulate emission.^ Two types of bags commonly used for bagging
are the open-top, sewn bag and the corner-fill, valve-type bag. The
open-top bag is held under a bagging machine which fills the bag to a
predetermined weight. After filling, the top is pinched together and
sealed. The corner-fill, valve bag is "factory closed"; that is, the
top and bottom are closed either by sewing or by pasting, and a small
3-47
-------
single opening or valve is left on one corner. Ammonium nitrate is
discharged into a bag through the valve, which closes automatically due
p
to the back pressure produced by the contents of the bag.l Dust is
emitted from each bagging method during the final stages of filling when
dust-laden air is displaced from the bag by the ammonium nitrate. The
potential for emissions during bagging is greater for coated material
than for uncoated material. Data are not available on emission quantities
(controlled or uncontrolled) from bagging operations. It is expected
that emissions from bagging operations consists primarily of the kaolin,
talc or diatomaceous earth coating materials.
3-^8
-------
3.3 REFERENCES
1. Rosser, W. A., et al. The Kinetics of Decomposition of Liquid
Ammonium Nitrate. Journal of Physical Chemistry. 67:1753-1757.
September 1963.
2. Kirk-Othmer (eds.). Encyclopedia of Chemical Technology, Second
Edition, Volume 9. New York, John Wiley & Sons, Inc., 1970.
p. 60.
3. Trip report. Capone, S. V., 6CA Corporation, to Noble, E. A., EPA:
ISB. September 8, 1978. p. 2. Report of visit to CF Industries
in Harrison, Tennessee.
4. Lowenheim, F. A. and M. K. Moran. Faith, Keyes and Clark's Industrial
Chemicals, Fourth Edition. New York, John Wiley & Sons, 1975.
pp. 97-99.
5. Trip report. Capone, S. V., GCA Corporation, to Noble, E. A.,
EPA:ISB. March 20, 1979. p. 9 Report of visit to Atlas Powder
Company in Joplin, Missouri.
6. Search, W. J. and R. B. Reznik. (Monsanto Research Corporation.)
Source Assessment: Ammonium Nitrate Production. (Prepared for
U. S. Environmental Protection Agency.) Research Triangle Park,
N. C. Publication No. EPA-6001/2-77-107i. September 1977. p. 17.
7. Memo from Bowen, M. L. Bowen, Radian Corporation, to file. December 15
1980. References for operating parameters of high density prill
plants.
8. Memo from Bowen, M. L., Radian Corporation, to file. December 15,
1980. Reference sources for EPA test data on uncontrolled emissions.
9. Trip report. Capone, S. V., GCA Corporation, to Noble, E. A.,
EPA:ISB. June 30, 1978. p. 1. Report of visit to N-Ren Corporation
in Pryor, Oklahoma.
10. Stover, J. C. (Cooperative Farm Chemicals Association.) Control of
Ammonium Nitrate Prill Tower Emissions. In: The Fertilizer Institute
Environmental Symposium. Washington, D. C., The Fertilizer Institute,
1976. pp. 268-272.
11. Memo from Bowen, M. L., Radian Corporation, to file. December 15,
1980. References for operating parameters of low density prill
plants.
12. Reference 10, p. 260.
3-49
-------
13. Carter, R. W. R. and A. 6. Roberts. The production of Ammonium
Nitrate Including Handling and Safety. (Presented at the Fertilizer
Society Meeting. London. October 23, 1969.) p. 16.
14. Memo from Bowen, M. L., Radian Corporation, to file. December 15,
1980. References for melt stream data for high and low density
prill plants.
15. Shearon, W. H. and W. B. Dunwoody. Ammonium Nitrate: A Staff-
Industry Collaborative Report. Industrial and Engineering Chemistry.
45_(3): p. 501. March 1953.
16. Bingham, E. C. Control of Air Pollution from Fertilizer Production.
In: Proceedings of the Second Annual Industrial Air Pollution
Control Conference. Knoxville, University of Tennessee, 1972.
p. 273.
17. Memo from Bowen, M. L., Radian Corporation, to file. December 16,
1980. References for uncontrolled prill tower emissions.
18. Reynolds, J. C. and R. M. Reed. (C&I Girdler.) Progress Report on
Spherodizer Granulation 1975-1976. (Presented at the Environmental
Symposium of the Fertilizer Institute. New Orleans. January 15,
1976.) p. 23.
19. Reference 18, p. 2.
20. Trip report. Bornstein, M. I., GCA Corporation, to Noble, E. A.,
EPA:ISB. August 2, 1978. p. 3. Report of visit to C&I Girdler in
Louisville, Kentucky.
21. Reference 18, pp. 8, 23.
22. Reference 20, p. 2.
23. Reference 20, pp. 2, 30.
24. Ruskan, R. Prilling Versus Granulation for Nitrogen Fertilizer
Production. Chemical Engineering. 83:114-118. June 7, 1976.
p. 116.
25. Letter and attachments from Schuyten, H., Chevron Chemical Company,
to Goodwin, D. R., EPA:ESED. March 2, 1979. 37 p. Response to
Section 114 letter, p. 13.
26. Reference 20, pp. 30, 31.
27. Trip report. Bornstein, M. I. and S. V. Capone, GCA Corporation,
to Noble, E. A., EPArlSB. June 23, 1978, p. 2. Report of visit
to Agrico Chemical Company in Blytheville, Arkansas.
3-50
-------
28. Memo from Bowen, M. L., Radian Corporation, to file. December 16,
1980. References for uncontrolled granulator emissions.
29. Reference 24, p. 115.
30. Reference 20, p. 13.
31. McCamy, I. W. and M. M. Norton. (Tennessee Valley Authority.)
Production of Granular Urea, Ammonium Nitrate and Ammonium Polyphosphate-
Process Review. (Presented at the International Conference on
Granular Fertilizers and Their Production. London. November 13-20,
1977.) p. 6.
32. Memo from Bowen, M. L., Radian Corporation, to file. December 16,
1980. References for cooler operating parameters.
33. Memo from Bowen, M. L., Radian Corporation, to file. December 16,
1980. References for predryer-dryer operating parameters.
34. Reference 15, p. 502.
35. Reference 27, p. 16.
36. Fluid-Bed Coolers for Ammonium Nitrate. Chemical and Process
Engineering. 49_:69. April 1968.
37. Memo from Bowen, M. L., Radian Corporation, to file. October 3,
1980. Summary of air temperatures, residence time, and moisture
content for high density prill coolers.
38. Letter and attachments from Farris, C. M., U.S.S. Agri-Chemicals,
to Noble, E. A., EPA:ISB. January 11, 1979. 18 p. Response to
Section 114 letter, p. 12.
39. Letter and attachments from Eichler, S. L., CF Industries, to
Goodwin, D. R., EPA:ESED. December 26, 1978. p. 7. Response to
Section 114 letter.
40. Letter and attachments from Atwood, J. D., Farmland Industires, to
Goodwin, D. R., EPA:ESED. December 14, 1978. 18 p. Response to
Section 114 letter. Attachment 5, p. 5.
41. Memo from Bowen, M. L., Radian Corporation, to file. December 16,
1980. References for uncontrolled cooler emissions.
42. Letter and attachments from Farris, C. M., U.S.S. Agri-Chemicals,
to Noble, E. A., EPA:ISB. April 12, 1979. 16 p. Response to
Section 114 letter, pp. 10-12.
3-51
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43. Letter and attachments from Cayard, D. E., Monsanto Agricultural
Products Company, to Noble, E. A., EPA:ISB. December 27, 1978.
43 p. Response to Section 114 letters, p. 23.
44. Letter and attachments from Patterson, D. J., N-ReN Corporation, to
Noble, E. A., EPA:ISB. March 26, 1979. 9 p. Response to Section 114
letter, p. 7.
45. Memo from Bowen, M. L., Radian Corporation, to file. December 18,
1980. Residence time and prill moisture for low density coolers.
46. Perry, R. H. and C. H. Chilton (eds.). Chemical Engineers' Handbooks,
Fifth Edition. New York, McGraw-Hill Book Company, 1973. p. 21-41.
47. Memo from Bowen, M. L., Radian Corporation, to file. October 30,
1980. Summary of coating and additive operations in the ammonium
nitrate industry.
48. Memo from Bowen, M. L., Radian Corporation, to file. January 2,
1981. Summary of percent coating in final AN product.
49. Reference 6, p. 4.
3-52
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4.0 HUSSION CONTROL TECHNIQUES
This chapter discusses techniques for controlling particulate
emissions from manufacturing processes in the ammonium nitrate (AN)
industry. Section 4.1 briefly reviews particulate control devices
currently in use. Section 4.2 presents a general description of each
emission control technique used in the industry and a discussion of the
design variables and factors affecting their performance. Emission test
data for each of the sources being considered in detail in this document
are presented in Section 4.3. Discussion of the test results and expected
control device performance in the ammonium nitrate industry are presented
in Section 4.4.
4.1 OVERVIEW OF CONTROL TECHNIQUES
The selection of a control device depends upon several factors,
including the source of emissions, the physical and chemical properties
of the particulate, and the characteristics of the exhaust stream containing
the particulate. The ammonium nitrate industry uses fabric filters and
a variety of wet scrubbers for particulate removal.
Fabric filters are not used for controlling emissions from solids
formation process equipment (prill towers and granulators) or solids
finishing process equipment (predryers, dryers, and coolers). The
hygroscopic nature of ammonium nitrate particulates, combined with the
moisture content of the gas streams, cause blinding of the filter.
However, fabric filters are used to control particulate emissions from
bagging and coating operations which deal with the finished dried product.
(Wet scrubbers are the predominate particulate emission control
device used in the ammonium nitrate industry. This is because scrubber
wastewater containing recovered ammonium nitrate can be readily utilized
as a fertilizer solution or reintroduced into the solution process^) Also,
wet scrubbers are less subject to caking by hygroscopic materials/
4-1
-------
Table 4-1 presents a summary of emission control devices currently
used on the emission sources under consideration in this document. The
following subsections briefly describe these devices.
4.1.1 High Density Prill Towers
Twelve high density prill towers currently use collection hoods
in conjunction with wet scrubbers. The wet scrubber only treats the air
captured by the collection hood, which is usually 20 to 25 percent of
the total prill tower airflow. One high density prill tower, although
equipped with a hood and bypass, does not bypass and treats the full
tower airflow. The tower airflow, in this case, is reduced by process
modifications. Eleven of these thirteen towers, including the one that
treats the full flow, use a wetted fibrous filter scrubber. Of the
remaining two towers, one uses a venturi scrubber and the other uses a
wetted mesh pad. Pressure drops for the wetted fibrous filter scrubbers
range from 1.50 to 6.5 kPa (6 to 26 in. W.G.). No information is
available on the operation of the venturi scrubber or the wetted mesh
pad.
Four high density prill towers treat total tower airflow with low
efficiency scrubbers. These scrubbers include one valve-tray scrubber,
two spray tower scrubbers equipped with a wetted mesh pad, and a knockout
chamber. The valve tray scrubber operates at a pressure drop of 2.7 kPa
(10.7 in. W.G.) and the spray tower scrubbers have a pressure drop of
? o
0.5 kPa (2 in. W.G.). ' No information is available on the operation
of the knockout chamber.
4.1.2 Low Density Prill Towers. Twelve of eighteen plants which
produce low density prills do not control their prill tower emissions.
However, five low density facilities employ collection hoods in conjunction
with a wetted fibrous filter scrubber. Pressure drops for these scrubbers
are reported to range from 1.50 to 6.5 kPa (6 to 26 in. W.G.). One low
density prill tower treats total tower airflow with an impingement type
scrubber operating at a pressure drop of 0.75 kPa (3 in. W.G.)«
4-2
-------
TABLE 4-1. EMISSION CONTROL TECHNIQUES USED
BY THE AMMONIUM NITRATE INDUSTRY5
Process Facility
Solids Formal ion
high Density
Prill Tower
Low Density
Prill Tower
Drum Granulalor
Pan Granulatcr
Solids FlnlsMnq
Predryer, Dryer
•£» or cooler
CO .-
Number of Sources
Included in Survey
20
18
6C
1
76d
Met Scrubbers Other Controls
Fibrous b Fabric
Filter Entrainment Cyclone Venturt Tray Mechanical Other None Filter Dry Cyclone No. Info.
12* - .11-33..
5 1 ..... iz ..
8 .... ...
1 ...
1 7 37 - 7 12 2 3 - 3
'Eleven of these scrubbers are fibrous filters and one is a wetted mesh pad.
Includes knockout chambers, spray towers, etc.
cTwo of the drum granulators have two entrainment scrubbers each.
Total number of solids finishing processes with available data. Some will have more than one control device or may be connected in series to a
single control device.
-------
4.1.3 Rotary Drum Granulators and Pan Granulators
At present, all rotary drum granulators are controlled by entrainment
scrubbers. These scrubbers typically operate with pressure drops of
3.5 kPa (14 in. W.G.).6
The one commercial pan granulator in operation is controlled by a
venturi scrubber with a pressure drop of 6.8 kPa (27 in. U.G.).
4.1.4 Solids Finishing Processes
Solids finishing equipment includes rotary drum predryers, dryers,
coolers and fluid bed coolers. A variety of scrubber types are used,
but wet cyclone scrubbers are the most common. Pressure drops for these
Q
scrubbers range from 0.5 - 1.5 kPa (2-6 in. W.G.). Mechanically aided
scrubbers are the second most used scrubber. These scrubbers have a
variety of designs, but all have a fan to aid in particulate removal and
operate at pressure drops very similar to those for the wet cyclones.
Other scrubbers in use include entrainment scrubbers and tray-type
scrubbers.
4.2 DESCRIPTION OF CONTROL TECHNIQUES
The following subsections present a detailed description of emission
collection and control devices applicable to the ammonium nitrate industry.
In addition, the sections provide a summary of their basic operating
principles and a discussion of the factors affecting the performance of
each device.
4.2.1 Fume Collection Hoods
Fume collection hoods are applied exclusively to prill towers. As
discussed in Chapter 3, prill tower emissions occur due to a variety of
processes, including fuming, microprill formation during jet breakup,
and prill fragmentation. Microprill formation and fuming occur in the
vicinity of the droplet forming device. The function of collection
hoods (Figure 4-1) is to capture these emissions by surrounding the
spray head or bucket in the prill tower and ducting the emissions to a
scrubber. Approximately 40 to 90 weight percent of total prill tower
emissions are reportedly captured in an air stream representing 15 to 30
percent of the tower airflow (Table 4-2). The collection hood reduces
4-4
-------
COLLECTION
HOOD
AMMONIUM NITRATE
SOLUTION
AIR
* INLET
EXHAUST
LIQUOR
IN
r
CONTROL
DEVICE
I
LIQUOR
' OUT
PRILLS
Figure 4-1. Prill tower / collection hood configuration.
4-5
-------
the amount of air requiring treatment, thus reducing the size of the
prill tower control apparatus. The major portion of the prill tower
airflow bypasses the collection hood and is vented to the atmosphere
untreated. Any of the following particulate scrubbers can be used in
conjunction with fume collection hoods.
4.2.2 Uet Scrubbing
A wet scrubber is a device in which a particle laden gas stream is
brought into contact with a liquid for the purpose of transferring
particulates from the gas to the liquid stream. There are many different
types of scrubbers and many different techniques to bring about the
gas/liquid contact. Consequently, wet scrubbers exhibit a broad range
of costs, collection efficiencies and power requirements.
The following subsections briefly describe the types of scrubbers
and typical operating parameters encountered in the ammonium nitrate
industry. In the sections below, the cut diameter is used to describe
and compare the performance of various scrubbers. The cut diameter of a
scrubber is the diameter of the particle that the scrubber will collect
at 50 percent efficiency. For example, a scrubber with a cut diameter
of 2 microns will remove particles of 2 microns in diameter at 50 percent
efficiency.
4.2.2.1 Wetted Fibrous Filter Scrubber. The wetted fibrous filter
scrubber is typically used in conjunction with a collection hood, but it
can also be used to control the entire exhaust flow.
This scrubber consists of two series of filter elements separated
by an atomizing spray chamber (see Figure 4-2). Each filter element,
made of compressed glass fibers, is irrigated to remove captured particles.
The exhaust stream first encounters a set of elements of relatively low
fiber density, designated "spray catcher" elements. These elements
collect the large, insoluble particulates (larger than 3 microns) that
may clog the second set of filter elements. According to the manufacturer's
literature, the dominant collection mechanism for these elements is
g
inertia! impaction. The pressure drop across the "spray catcher" elements
is 0.25 to 0.50 kPa (1 to 2 in. W.G.).
4-6
-------
ATOMIZING |L
SPRAYS T
HIGH EFFICIENCY
ELEMENTS
SPRAY CATCHER
ELEMENTS
EXHAUST FROM
COLLECTION
HOOD
' SCRUBBER
! SOLUTION
TANK
FIBER
PACKING
ELEMENT
GAS FLOW
SPRAY CATCHER
ELEMENTS
HIGH EFFICIENCY
ELEMENT
Figure 4-2. Detail of a wetted fibrous filter scrubber. '
4-7
-------
The remaining participates in the gas stream flow into the spray
chamber where some of them impinge on the water droplets. The particle
laden droplets are then removed from the gas stream by the second set of
filter elements, which are designated as "high efficiency" elements.
These high efficiency elements contain fibers that are compressed to a
greater density than the spray catcher elements. The pressure drop
across these elements is about 1 to 5 kPa (4 to 20 in. W.G.) for prill
tower applications. The manufacturer's literature states that the
dominant collection mechanism for these elements is Brownian movement of
the particles. Brownian movement causes the particles to collide with
1 o
the glass fiber mat where they are collected. A collection efficiency
of 95 to 99.5 percent is reported for particles under 3 microns in
diameter, as well as 100 percent collection efficiency for particles
larger than 3 microns. (See Figure 4-3).
The major factor affecting performance of the wetted fibrous filter
scrubber is airflow rate. As stated earlier, the two filters have
different particle collection mechanisms and capabilities. Because of
these differences, the effect on collection efficiency of changes in gas
airflow, particle concentration or particle size is reduced. A decrease
in airflow lowers the collection efficiency of the "spray catcher"
elements which depend on particle impaction, but increases the time
allowed for Brownian movement and, thus, increases the collection
efficiency of the "high efficiency" elements. Higher airflows increase
the inertial impaction of particulates on the "spray catcher" elements,
while reducing the time allowed for Brownian movement on the "high
efficiency" elements. These counter-balancing trends result in negligible
collection efficiency shifts with changes in airflow. The same is also
true for particle size or concentration shifts.
4.2.2.2 Tray-Type Scrubbers. A tray-type scrubber is shown in
Figure 4-4. It consists of a vertical tower containing one or more
transversely mounted trays. Particulate laden gas enters the tower
bottom and bubbles up through valves, perforations or other types of
4-8
-------
I
vo
O
It,
IL.
Ul
O
t—I
O
u
100
99
95
90
80
70
0.025
0.1
0.3 0.5
PARTICLE SIZE, (,m
Figure 4-3. Collection efficiency vs. particle size for a
wetted fibrous filter scrubber.''*
-------
CLEAN GAS
OUTLET
DIRTY GAS
INLET
LIQUOR
INLET
SUMP
TRAYS
LIQUOR
OUTLET
Figure 4-4. Tray-type scrubber.
4-10
-------
openings in each tray before exiting through the top of the tower.
Usually scrubbing liquid is introduced at the top plate, where it flows
across, over a retaining dam, and through a downcomer to reach the plate
b el ow.
Tray scrubbers do not exhibit the same removal efficiency for all
particle sizes. They show a sharp efficiency drop at a specific particle
size, which is determined primarily by the diameter of the plate perforations
used. The cut diameter for a well designed tray scrubber is 2-3 microns.
The liquid-to-air ratio for these devices ranges from 670 to 2010 liters/1000
m3 (5 to 15 gal/1000 ft3).15
The major factor affecting efficiency for a tray scrubber is pressure
drop. Generally, higher pressure drops result in greater removal
efficiencies. The number of trays, the size of the orifices in the
tray, and the velocity of the gas stream through the scrubber control
the pressure drop of the scrubber.
Manufacturers' performance curves show an increase in particulate
removal with the addition of tower trays. Figure 4-5 illustrates this
effect for a tray scrubber used in the ammonium nitrate industry for a
variety of particle sizes. The efficiency of the vertical axis, termed
standard efficiency, is for a standard 0.37 kPa (1.5 in W.G.) pressure
drop per tray.
Increasing the pressure drop across each tray through the use of
smaller orifices also increases removal efficiencies. Figure 4-6
illustrates this effect. For any given scrubber efficiency, the efficiency
at a higher pressure drop can be read.
A higher liquid-to-gas ratio can usually increase particulate
removal. However, an optimum liquid flow rate is usually maintained,
which insures adequate liquor for particulate removal without blocking
the airflow through the tray orifices.
4.2.2.3 Spray Tower Scrubbers. Spray tower scrubbers (Figure 4-7)
typically consist of a vertical or horizontal tower containing banks of
spray-nozzles. Either countercurrent, concurrent or crossflow spray
configurations are used to spray droplets into the gas stream.
4-11
-------
u
c
0)
•r—
U
.C. .Q
.!_, t.
" I
id
to
3456
Particle Size, Microns
8
10
Figure 4-5. Standard fractional efficiency for tray-type scrubber.
16
-------
ta
•
3
•
c
••—
in
o
01
•1~
u
•r"
t
inn
98
96
92
90
08
86
84
82
00
90
91
92
93 94 95 96 97
High Pressure Drop Efficiency
Figure 4-6. Effect of pressure drop on tray-type scrubber efficiency-^6
98
99
100
-------
DIRTY GAS INLET
CLEAN GAS OUTLET
s.y
X
LIQUOR INLET
I
LIOUOR OUTLET
Figure 4-7. Spray tower scrubber.
4-14
-------
Particles in the gas stream impinge on the liquid droplets, then are
collected and removed from the bottom of the tower. Droplet properties
are defined by the nozzle configuration, the type of liquid being atomized,
and the pressure at the nozzle. Nozzle pressure is typically 790 to
1,480 kPa (100 to 200 psig) but can be as high as 2,860 kPa (400 psig)
17 18
to remove submicron particles. *
Pressure drops across these scrubbers typically range from 0.12-
0.50 kPa (0.5-2 in. W.G.), with gas velocities of 0.37 to 1.5 m/sec (1.5
to 5.0 ft/sec). The liquid-to-gas (L/G) ratio used in spray towers is
generally 400 to 2674 liters/1000 m3 (3 to 20 gal/1000 ft3).18'19 No
performance curves are available for these scrubbers.
Factors reported to affect spray tower performance include droplet
size, relative velocity between droplets and gas airflow, and the liquid-
to-gas ratio. Large droplets provide less total surface area for impaction,
thus decreasing the spray tower's particulate removal efficiency. On
the other hand, small droplets increase particulate removal efficiency,
since a larger total surface area is available for particle capture.
The relative velocity between droplets and gas airflow also determines
removal efficiency. Large droplets have a higher relative velocity and
improved chances of particle-droplet collisions because of the droplet's
larger terminal settling velocity. Smaller droplets have a lower relative
droplet-to-gas velocity, and, if too small, will be entrained in the
rising gas stream. Therefore, an optimum droplet size can be found to
enhance spray tower efficiency, depending on the particle size distribution
and the flow rate of the gas stream. One optimum droplet size reported
is in the range of 500-1,000 microns for particle sizes ranging from 2-
19
10 microns. Spray towers are capable of handling large gas airflows
if the droplet size and pressure are adjusted accordingly.
The liquid-to-gas ratio also impacts tower performance. It must be
high enough to insure effective particulate capture by the water droplets,
but not so high that it hinders the flow of gas through the spray tower.
4-15
-------
4.2.2.4 Venturi Scrubbers. A typical venturi scrubber is shown in
Figure 4-8. Scrubbing liquid is injected into the gas stream upstream
of the throat area. The moving gas stream first atomizes the liquid
into droplets, then accelerates them through the throat. In the high
turbulence zone associated with the venturi throat, particles collide
with and are collected by the atomized liquid droplets. The particle
laden liquid is then removed from the gas in a cyclonic separator.
Venturi scrubbers typically operate at pressure drops of 2.5 to
20 kPa (10 to 80 in. W.G.) and liquid to gas ratios of 400 to 1300 liters/1000 m3
(3-10 gal/1000 ft3). Scrubber capacity ranges from 1000 to 3400 m3/min
(35,000 to 120,000 ft3/min). High gas velocities, usually 60-180 m/sec
(200-600 ft/sec), are needed to keep the relative velocities between the
gas and scrubber liquid droplets between 35 and 150 m/sec (120-500 ft/sec).
The air velocity creates turbulence which mixes the particles and liquid
droplets, thus increasing collection efficiency due to impingement and
interception. Venturi scrubbers have cut diameters between 0.05 and
20 21 22
0.1 microns, depending on the pressure drop. ' '
Operating variables which affect venturi scrubber performance
include pressure drop and the liquid-to-gas ratio. As shown in Figure 4-9,
the collection efficiency for a specific particle size can be increased
by increasing the pressure drop, and therefore the gas velocity. One
type of venturi scrubber has a variable throat in order to maintain the
23
pressure drop, and thus collection efficiency, at varying gas flows.
Like other wet scrubbers, the liquid-to-gas ratio for venturi scrubbers
must be great enough to effectively sweep the gas flow, but not so great
it causes flooding.
4.2.2.5 Entrainment Scrubbers. Entrainment scrubbers (also
referred to as orifice type, self-induced spray or impingement scrubbers)
utilize the velocity of the contaminated gas stream passing over the
surface of a liquid to atomize part of the liquid. These scrubbers
feature a shell that guides the particle laden gas stream so that it
impinges on and skims over the liquid surface before reaching a gas exit
4-16
-------
TOP VIEW
LIQUOR
INLET
FLOODED
ELBOW
DIRTY
GAS IN LET
CLEAN
GAS OUTLET
CYCLONIC
SEPARATOR
Figure 4-8. Venturi and cyclonic scrubber.
4-17
-------
I
I—"
00
o
UJ
O
EL
u.
UJ
O
2
UJ
ir
99.9.
99.5
99.0-
97-
95-
90-
80-
70-
60-
50
.1
T I I I I I I I
.3 .4 .5 .6 .7 .8 .9 1.0
i r i r
6 7 8 9 10
PARTICULATE DIAMETER urn
Figure 4-9. Collection efficiency vs. particle diameter for a venturi scrubber.25
-------
duct (see Figure 4-10). The airflow atomizes some of the liquid into
droplets; these act as a particle collecting and mass transfer surface.
Particle collection results from both inertia! impaction of the particles
in the gas stream on the liquid surface and by impingement of the particles
nc
on the atomized droplets. The particle laden droplets are removed
from the gas stream by gravity and a set of spinner vanes. The spinner
vanes force the droplets to contact the liquid surface and the sides
of the device where they flow down to the sump.
The cut diameter for this type of entrainment scrubber ranges from
0.08 to 0.3 microns. The pressure drop ranges from 1-4 kPa (4-16 in
27
W.G.). Figure 4-11 presents the collection efficiency curves for this
scrubber as a function of particle size and pressure drop.
The most important factor determining entrainment scrubber performance
is pressure drop. Pressure drop may be adjusted by changing the liquid
90
level in the sump. Too low a pressure drop reduces impaction which
decreases the scrubber collection efficiency. An excessive pressure
drop reduces collection efficiency because of insufficient liquid to gas
contact. Pressure drop is affected by gas airflow, but in entrainment
scrubbers it is also affected by gas velocity. Entrainment scrubbers
depend on the velocity of the inlet air to atomize the scrubber liquid.
Therefore, even modest turndowns or reductions in air velocity will
reduce the scrubber's collection efficiency. Entrainment scrubbers used
in the ammonium nitrate industry handle the turndown problem by adjusting
the gas nozzle, which directs the gas airflow into the liquid, to accomodate
changes in the inlet air velocity so that collection efficiency will not
be affected.27
4.2.2.6 Mechanically Aided Scrubbers. Mechanically aided scrubbers
rely on fan blades for particle collection. Scrubbing liquid is typically
introduced at the hub of the rotating fan blades. Particles in the gas
stream are captured as they impinge on the blades, and on the liquid
droplets atomized by the fan blades. Some liquid runs over the blades,
washing them of collected particles. This liquid atomizes as it leaves
4-19
-------
OUTLET
INLET
SPINNER
VANES
LIQUOR
INLET
SUMP
LIQUOR
OUTLET
Figure 4-10. Typical entrainment scrubber.
4-20
29
-------
COLLECTION EFFICIENCY VS PARTICLE SOS
M.90
99.95
99.90
99.M
99.50
S9.00
90.00
94.00
90.00
80.00
s.o.
TOJ
Wwmae OUMgTEB M MCKNS
Figure 4-11,
Collection efficiency of entrapment scrubbers
as a function of particle size and pressure drop
(courtesy of the Western Precipitation Division of
Joy Manufacturing Company).27
4-21
-------
the fan wheel and is recaptured by the fan housing, which drains into a
sump. Figure 4-12 shows an example of a mechanical centrifugal scrubber.
Pressure drops for these scrubbers are low (0.25-1.5 kPa (1-6 in.
W.G.)) and have little effect on removal efficiency, because the fan
blades primarily atomize the scrubber liquor instead of increasing the
gas flow rate and also serve as a collection device. ' Mechanical
centrifugal scrubbers generally have a cut diameter below 1 micron and
liquid-to-gas ratios of 2680 to 5360 liters/1000 m3 (20 - 30 gal/1000 ft3).31
No performance curves for these scrubbers are available.
One factor affecting performance of this device is the amount of
liquid on the fan blade. If too little liquid is used, the particles in
the gas stream will pass on through the device. Too much liquid increases
the amount of wastewater to be handled, but does not significantly
increase performance. Changes in gas flow do not significantly affect
scrubber performance. However, higher fan velocities generally cause
greater impingement of particles on the fan blades, increasing particulate
oo
removal.
4.2.2.7 Wet Cyclones. Wet cyclones, usually cylindrical in shape,
impart a rotational motion to the incoming gas stream by tangentially
introducing the gas stream into the scrubber, or by directing the gas
stream against stationary swirl vanes (Figure 4-13). Liquid is sprayed
through the rotating gas stream either outward from a central manifold,
or inward from the collector wall. Particles in the swirling gas stream
impact on the liquid droplets. The centrifugal force and high velocity
of the gas stream carry the particle laden droplet out to the cyclone
wall, where a continuous water film washes it down the wall and out of
the system.
Wet cyclones generally operate at 0.50-1.5 kPa pressure drops
Q
(2-6 in. W.G.). This pressure loss is directly proportional to the gas
stream flow rate. Wet cyclone scrubbers are designed for cut diameters
between 2 and 3 microns, with liquid-to-gas ratios of 268 to 1340 liters/1000
m3 (2-10 gal/1000 ft3).33 No efficiency curves for these scrubbers are
available.
4-22
-------
WATER
SPRAYS
VANES
SUMP
WATER
DRAINS
Figure 4-12. Mechanical centrifugal scrubber.
31
4-23
-------
/- \
GAS
OUTLET
LIQUID
INLET
LIQUID
OUTLET
Figure 4-13. Wet cyclone scrubber.
4-24
-------
Since it directly influences pressure drop the gas flow rate is the
most important factor affecting the performance of a wet cyclone. If
the gas flow rate is lowered, scrubber efficiency will be reduced.
4.2.3 Fabric Filters
Fabric filters (baghouses) are high efficiency collection devices
used quite extensively in the ammonium nitrate industry for control in
bagging and coating operations. An average removal efficiency for a
A *
fabric filter is 99 percent. Figure 4-14 depicts a typical fabric
filter system. In the type of design shown, the airstream enters the
baghouse and is pulled up into fabric sleeves located throughout the
baghouse. The air pulled through these fabric sleeves is exhausted to
the atmosphere, while dust remains trapped in the weave of the fabric,
forming a layer of dust on the bag. The pressure drop through the bag
increases as this dust layer builds up. The dust is eventually removed
from the bag by one of several bag cleaning methods.
An important operating principle for fabric filters is that effective
filtering of the dusty airstream is accomplished, not only by the fabric,
but also by the dust layer which forms on the fabric. This dust layer
bridges the gaps between adjacent fibers and increases the chances of
impact ion and interception of small particles. For this reason, too
frequent cleaning can actually decrease efficiency by not allowing a
dust layer to accumulate between cleaning cycles.
Materials available for bag construction are numerous. They include
p
cotton, Teflon , coated glass, orlon, nylon, dacron and wool. The type
of material selected depends upon many factors, including temperature,
frequency of cleaning, ease of removing particles, resistance to chemical
attack, and abrasion characteristics of the collected particles.
Factors affecting baghouse performance include air-to-cloth ratio,
type of fabric used, method and interval of cleaning, pressure drop, and
the properties of the exhaust being cleaned. Air-to-cloth ratio is
dimensionally equivalent to a velocity; and it indicates the average
face velocity of the gas stream through the effective area of the fabric.
4-25
-------
BRANCH
'HEADER
CLEAN AIR
OUTLET
NOZZLE
BAFFLE
PLATE
PYRAMIDAL OR
TROUGH HOPPERS
ACCESS
DOOR
Figure 4-14. Fabric filter.
35
4-26
-------
An excessive air-to-cloth ratio results in excessive pressure loss,
reduced collection efficiency, rapid bag blinding, and increased wear on
the fabric. Too low an air-to-cloth ratio reduces collection efficiency,
since the filtering dust layer may not be allowed to accumulate between
cleaning cycles.
Pressure drops in baghouses depend on a variety of factors, including
air-to-cloth ratio, fabric type and cleaning cycle. Pressure drops
typically increase between cleaning cycles as the dust layer increases.
Pressure drops of from 0.5-2 kPa (2-8 in. W.G.) are common for many
applications.
4.2.4 Modifications in the Process Parameters
In addition to the control devices mentioned above, emissions from
high density prill towers can be reduced by varying process parameters.
One industry study was conducted in 1973 on a high density prill tower
to determine the effect on the emission rate of raising the melt pH,
reducing the melt spray temperature, reducing the tower air flow and
adding magnesium oxide to the spray melt.
As the pH increased from 5.5 to 7.0, emission rates reduced by
approximately one-third and prill formation became larger and irregular
in size and shape. The study concluded that while emissions decreased
at increased melt pH's, plants could not operate at pH's of 7.0 or above
without equipment modification or changes in prill quality standards.
When the spray temperature was reduced from 455 K (360°F) to 447 K
(345°F), emissions were reduced by as much as 20 percent. This reduction
in emissions is believed to be due to the reduction of fuming.
To study the effect of lower tower airflows on emissions, the
airflow was reduced from 3823 Nm3/min (135,000 scfm) to 2265 Nm /min
(80,000 scfm). The data showed that while emission concentrations
increased due to the reduced airflow, emission rates remained normal.
No emissions reduction was observed.
MgO was added continuously to the head tank of a high density prill
tower to maintain concentrations of 0.10 to 0.14 weight percent of free
4-27
-------
MgO. The emission rates measured from all samples were considered
normal and showed no change.
These emissions tests were conducted by using a test method other
than the EPA method ("modified" Method 5 or AN-MOD 5) and should only be
used as an indication of possible performance. Regardless of the potential
emissions reductions possible with the above modifications, the study
concluded that control equipment would still be necessary to reduce
emissions on high density prill tower operations to meet state air
emission regulations.
4.3 EMISSIONS TEST DATA
The following section presents the available test data for solids
formation and solids finishing processes in the ammonium nitrate industry.
The information is divided into two categories: data supplied by industry
and state air pollution agencies (hereafter referred to as industry
data), and data collected by EPA during source testing conducted for
this study. In general, available industry data are limited and were
obtained by widely varying sampling and analytical techniques. Because
of the differences in sampling and analytical procedures, direct comparisons
between industry and EPA data cannot be made.
4.3.1 High Density Prill Towers
As mentioned in previous sections, the most commonly used control
system for high density prill towers is a collection hood and a wetted
fibrous filter scrubber. Several of these systems have been tested by
industry.
Table 4-2 summarizes available mass emission test results for high
density prill towers, in addition to low density prill towers and
granulators. For high density prill towers, uncontrolled particulate
emissions range from 0.81 to 2.74 g/kg (1.63 to 5.48 Ib/ton) and controlled
emissions range from 0.03 to 0.85 g/kg (0.07 to 1.69 Ib/ton). Some
treatment systems only treat a portion of the total tower emissions;
reported controlled emissions for these systems are the sum of the
treated air emissions and the bypass emissions.
4-28
-------
TABLE 4-2. HIGH DENSITY AND LOW DENSITY PRILL
TOWER AND GRANULATOR EMISSIONS38
Uncontrolled Emissions Controlled Emissions
q/kg (Ib/ton) q/kg (Ib/ton)
Plant
Aa
Gb
Hb
Ib
Pt>
Zb
Ob
Jb
zb
za
Ba
£b
Da
Type of Plant
High Density
Prilling
High Density
Prilling
High Density
Prilling
High Density
Prilling
High Density
Prilling
High Density
Prilling
High Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Drum Granulator
Drum Granulator
Pan Granulator
Ammonia
28.80
(57.60)
NA
NA
NA
NA
NA
NA
NA
NA
0.13
(0.26)
30
(60)
NA
0.07
(1.15)
Ammonium
Nitrate
1.60
(3.20)
2.74
(5.48)
1.16
(2.33)
1.28
(2.55)
1.93
(3.86)
NA
0.82
(1.63)
0.22
(0.45)
NA
0.39
(0.78)
147
(295)
NA
1.34
(2.68)
Control Device
Two Tray Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Wet Impingement
Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Collection Hood
Wetted Fibrous
Filter Scrubber
Entrapment
Scrubbers
Entrainment
Scrubber
Variable Throat
Venturi Scrubber
Ammonia
4.70
(9.40)
NA
NA
NA
NA
NA
NA
NA
NA
0.07
(0.14)
0.09
(0.18)
NA
d
Ammonium
Nitrate
0.85
(1.69)
0.40
(0.81)
0.51
(1.02)
0.16
(0.32)
0.24
(0.48)
0.03
(0.07)
0.29
(0.57)
0.11
(0.21)
0.06
(0.13)
0.25
(0.49)
0.22
(0.43)
0.61
(1.23)
0.02e
(0.04)
Percent of
Airflow to
Device
100
c
33
21
25
NA
25
DNA
NA
17
ONA
DNA
DNA
Percent of
Emissions to
Control Device
100
88
NA
84
89
NA
67
100
NA
42
100
100
100
DNA = Does Not Apply
NA > Not Available
aEPA Test Data.
Industry Data (not necessarily comparable with EPA data).
cCons idsred confidential by this plant but within range of other reported values.
Controlled emissions are from the evaporator and pan granulator. Controlled ammonia emissions are
unavailable due to the high ammonia emissions from the evaporator.
Controlled emissions are from the evaporator and pan granulator. The pan granulator AN participate
emissions constitute 98 percent by weight of the scrubber inlet emission.
4-29
-------
EPA tested a high density prill tower controlled by a two tray
scrubber with a pressure drop of 2.7 kPa (10.7 in. W.G.) (see Appendix
A).2 The emission rate was reduced from 1.60 g/kg (3.20 Ib/ton) to 0.85
g/kg (1.69 Ib/ton) of product. The AN particulate concentration was
0.07 g/dNm3 (0.03 gr/dscf) at the inlet to the scrubber and 0.036 g/dNm3
(0.016 gr/dscf) at the outlet. Average visible emissions from the
scrubber ranged from 10 to 20 percent opacity. No particle size data
was available for this test.
4.3.2 Low Density Prill Towers
The most commonly used control technique applied to low density
prill towers is the same as that for high density prill towers: a
collection hood and a wetted fibrous filter scrubber. As shown in
Table 4-2, uncontrolled particulate emissions range from 0.21 g/kg
(0.42 Ib/ton) to 0.69 g/kg (1.38 Ib/ton), while controlled emissions
range from 0.06 to 0.25 g/kg (0.13 to 0.49 Ib/ton).
EPA's testing of a collection hood/wetted fibrous filter system,
with a pressure drop of 3.5 kPa (14 in. W.G.), measured uncontrolled
emissions of 0.39 g/kg (0.78 Ib/ton). *42 Controlled emissions, the
sum of emissions from the wetted fibrous filter scrubber and the bypass,
were 0.24 g/kg (0.48 Ib/ton). Particle size data for the bypass and the
inlet to the wetted fibrous filter scrubber are presented in Figure 4-15.
EPA also measured particulate concentrations. For the bypass, the
O
average concentration was 0.013 g/dNm (0.0056 gr/dscf); the fibrous
filter inlet and outlet concentrations were 0.048 g/dNm3 (0.021 gr/dscf)
and 0.005 g/dNm3 (0.002 gr/dscf), respectively.42 Opacity reading from
the bypass ranged from 0-8 percent and was 0 at the scrubber outlet.
4.3.3 Rotary Drum Granulators
At present, all rotary drum granulators are controlled by entrainment
scrubbers. The available emission test data from industry for two drum
granulators are shown in Table 4-2. One of the plants measured only
controlled emissions and reported these to be 0.61 g/kg (1.23 Ib/ton).
The other plant uses an entrainment scrubber with a 2.7 kPa (10.9 in. W.G.)
4-30
-------
c
o
o
CO
OJ
r—
U
•r—
•M
(O
0.
Runs 1,2 &
Scrubber
Inlet
5 10 20 30 50 70 90 99
Weight Percent Less Than Stated Size
Figure 4-15. Particle size distribution from the bypass
and the scrubber inlet at a low density
prill tower.
-------
pressure drop and results of EPA testing show that emissions were reduced
from 147.2 g/kg (294.6 Ib/ton) to 0.22 g/kg (0.43 lb/ton).45'46 Figure
4-16 presents the particle size characteristics of emissions from the
rotary drum granulator. The EPA test also reports that visible emissions
from the scrubber ranged from 10-20 percent opacity.
4.3.4 Pan Granulators
There is only one pan granulator in operation in the U. S. and it
uses a venturi scrubber with a pressure drop of 6.75 kPa (27 in. W.G.)
for emission control. EPA tests measured uncontrolled AN particulate
emission from the pan granulator at 1.34 g/kg (2.68 Ib/ton). Measured
outlet emissions from the venturi scrubber include both evaporator and
pan granulator emissions, so actual controlled emissions for the pan
granulator alone are not available. However, controlled emissions from
the pan granulator can be estimated based upon its proportion of the
inlet emissions. The estimated controlled emission rate is 0.02 g/kg
4R
(0.04 Ib/ton). Controlled visible emissions ranged from 5 to 15
4Q
percent opacity.
4.3.5 Solids Finishing Processes
Solids finishing equipment includes rotary drum predryers, dryers,
coolers and fluid bed coolers. These units are discussed together
because of their similarities in operation and emissions. As shown in
Figure 4-17, particle sizes for uncontrolled emissions from various
types of solids finishing equipment are similar. Each of these facilities
have emissions with 99.7 percent of the particles greater than one micron.
Presently, wet cyclones are the most common wet scrubber used for
solids finishing equipment. The designs for these scrubbers are varied,
but all report pressure drops between 0.5-1.5 kPa (2-6 in. W.G.). Other
wet scrubbers used to control emissions are mechanical scrubbers,
entrainment scrubbers, spray towers and tray scrubbers. Of the wet
scrubbers used to control these emissions, all report removal efficiencies
greater than 95 percent for particles greater than 5 microns in size.
4-32
-------
.£»
I
OJ
U)
V)
I
u
-------
E
u
(1)
4J
(O
•r—
a
id
Q.
10
8
6[
5
4
3
d
.9
.8
.7
.6
.5
.4
.3
Drum Granulation Cooler Q
Drum Granulation Cooler Q
Pan Granulation PrecoolerA
Low Density Predryer Q
Low Density Dryer+
Low Density CoolerV
PLANT
E
B
D
C
C
C
.2
.1
.01 .1 .2 .5 1 2
Figure 4-17.
5 10 50 80 90
Weight Percent Less Than Stated Size
95
Average particle size distribution from solids
finishing processes.
-------
EPA and industry emission data on these facilities are presented in
Table 4-3. Uncontrolled emission factors from both industry and EPA
tests range from 0.15 to 93.7 g/kg (0.3 to 187.4 Ib/ton) of ammonium
nitrate. Controlled emission factors range from 0.003 to 0.65 g/kg
(0.007 to 1.3 Ib/ton) of ammonium nitrate. EPA tested the solids finishing
equipment at high density, low density, drum granulation and pan granulation
plants. Uncontrolled emissions for these EPA tests ranged from 0.83 to
93.7 g/kg (1.66 to 187.4 Ib/ton) and the controlled emissions ranged
from 0.03 to 0.47 g/kg (0.07 to 0.94 Ib/ton). Appendix A contains
details of the EPA testing of these facilities.
4.4 EVALUATION OF CONTROL DEVICE PERFORMANCE
This section presents an evaluation of the EPA emission data obtained
during this study. This evaluation includes: (1) a general examination
of the data to determine its relative accuracy and representativeness,
and (2) a discussion of the control devices used and their removal
capabilities. More details of the tests are presented in Appendix A.
4.4.1 High Density Prill Tower
EPA has tested only one high density prill plant (Plant A) in the
ammonium nitrate industry. As can be seen from Tables 3-3 and 3-6, this
plant's prill tower design and process parameters (like spray melt
temperature, airflow rate and prill temperatures) are similar to other
high density prill plants in the industry. Therefore, the process
operation for Plant A can be considered representative of other plants
in the industry. The tower at this plant has a 2.7 kPa (10.7 in. W.G.)
p
pressure drop two-tray scrubber that controls total tower airflow.
This is the only high density plant in the industry which uses this type
of scrubber. The scrubber usually controls evaporator and prill tower
emissions, but during testing only prill tower emissions were controlled.
Uncontrolled emissions were reduced from 1.6 g/kg (3.2 Ib/ton) to
0.85 g/kg (1.69 Ib/ton) by the two-tray scrubber, a 47 percent removal
39
efficiency. During the test the plant was operating normally. Nonisokinetic
conditions occurred for two runs; however, the results were used in the
4-35
-------
TABLE 4-3, SOLIDS FINISHING PROCESS EMISSIONS
a,51
u>
Plant Facility
Predryers
Cow Density
I* Rotary Drum Predryer'
Lb Rotary Drum Predryer'
Z Rotary Drum Predryer
Z Rotary Drum Predryer
Dryers
Low Density
Lj Rotary Drum Dryers
l| Rotary Drum Dryer
Zb Rotary Drum Dryer
Z Rotary Drum Dryer
Coolers
TngOenslty
A Rotary Drum Cooler
G Rotary Drum Cooler
Zb Fluid Bed Cooler
low Density
Lj Rotary Drum Cooler
1-2 Rotary Drum Cooler
Zb Fluid Bed Cooler
Z Fluid Bed Cooler
Drum Granulation
E Rotary Drum Cooler
Pan Granulation
D Rotary Drum Precooler
Control
Device
Spray Tower
Wet Cyclone
Tray Scrubber
Tray Scrubber
Spray Tower
Wtt Cyclone
Tray Scrubber
Tray Scrubber
Spray Chamber
Wetted Mesh
Pad
Wet Cyclone
Spray Tower
Wet Cyclone
Wet Cyclone
Wet Cyclone
Entrapment
Scrubber
Wet Cyclone
Uncontrolled
Emissions g/kq (Ib/ton)
Pressure Drop Annonium
kPa(ln. W.6.) Ammonia Nitrate
0.5-1.25 (2-5) - 3.2 (6.4)
0.75-1.5 (3-6) - 4.1 (8.2)
.
0.29 (0.58) 37.3 (74.6)
0.5-1.25 (2-5) - 22.8 (45.7)
0.75-1.5 (3-6) - 7.8 (15.6)
* * *
1.3 (2.6) »3.7 (187.4)
1.0 (4.0) 0;03 (0.05) 0.83 (1.66)
0.5-0.75 (2-3) - 0.15 (0.3)
-
0.5-1.25 (2-5) - 19.2 (38.4)
0.75-1.5 (3-6 - 35.2 (70.5)
-
0.29 (0.58) 37.8 (75.7)
3.3 (13.1) 1.18 (2.35) 8.6 (17.3)
1.4 (5.6) 0 18.0 (36.0)
Controlled
Emissions g/kg (Ib/ton)
Awtonlun
AwnonU Kttrate
0.13 (0.26)
0.12 (0.25)
0.03 (0.06)
0.18 (0.36)'
0.18 (0.37)
0.1 (0.2)
0.03 (0.06)
0.47(0.94)"
0.01 (0.02) 0.075 (0.15)
0.003 (0.007)
0.31 (0.61 1*
0.16 (0.32)
0.65 (1.3)
0.07 (0.14)d
•
0.02(0.03) 0.03 (0.07),
0 0.12 (0.23)
Percent
Ooacitv
-
-
0.2f
-
.
.
0.2f
0
-
.
-
-
-
0
-
0-10
aEPA data unless otherwise noted.
bln
-------
computation of emissions since the emission rates were similar for all
three runs. Due to particle collection problems, particle size data
were invalid.
4.4.2 Low Density Prill Towers
EPA also tested one low density prill tower (Plant Z). This tower
is equipped with a collection device and wetted fibrous filter scrubber
to reduce emissions. The prill tower operating parameters at this
plant, such as melt temperature, airflow, and prill temperature, are
similar to other plants in the industry. Therefore, the tower operation
can be considered representative of other low density plants. The
collection device design used is proprietary, but functions similarly
to others in the industry. This collection device captures 17 percent
of the tower airflow and ducts it to a 3.5 kPa (14 in. W.G.) pressure
drop wetted fibrous filter scrubber.
EPA measured uncontrolled emissions of 0.39 g/kg (0.78 Ib/ton) from
this tower. These emissions contained both bypass emissions (0.22 g/kg
(0.45 Ib/ton)) and scrubber inlet emissions (0.16 g/kg (0.33 Ib/ton)).
The wetted fibrous filter scrubber reduced emissions collected by the
collection device to 0.02 g/kg (0.04 Ib/ton). When combined with
bypass emissions, the total controlled emissions were 0.24 g/kg (0.48
Ib/ton).42
The wetted fibrous filter scrubber removed 88 percent of the mass
emissions received at its inlet. This value is less than the lowest
removal efficiency reported by the manufacturer in Figure 4-3 (95 percent).
The lower than expected removal efficiency is probably due to low particulate
loadings (0.16 g/kg (0.33 Ib/ton)). Also, particle sizes measured at
the scrubber inlet indicate that approximately 50 percent of the particles
were less than 1.2 microns (Figure 4-15). Even though the 88 percent
removal efficiency is lower than expected, the scrubber is still effective
in controlling AN emissions.
The total emissions reduction, including the bypass emissions, was
only 38.5 percent. This low overall emissions reduction was probably
due to the fact that the collection device only collected 41 percent of
the uncontrolled emissions.
4-37
-------
During the test, the process operation showed no anomalies and no
sampling problems were reported.
4.4.3 Granulaters
4.4.3.1 Drum Granulators. EPA tested uncontrolled and controlled
emissions for only one granulator (Plant B). As stated in Section
3.2.4.1, all granulators in the industry are of the same design and
operation. In addition, all granulation plants report using an entrainment
scrubber to control granulator emissions. The entrainment scrubber
tested at this plant has a 2.7 kPa (10.9 in. W.G.) pressure drop.45
Uncontrolled emissions measured for the granulator at Plant B were
147.2 g/kg (294.6 Ib/ton). The entrainment scrubber reduced uncontrolled
emissions to 0.22 g/kg (0.43 Ib/ton), a 98 percent removal efficiency.
In Figure 4-16, the EPA's particle size test results are presented. The
entrainment scrubber's removal of these particles corresponds with the
manufacturer's efficiency curves presented in Figure 4-11.
The plant reported normal operation during testing. The only
problem encountered during the test was excessive particulate loading at
the inlet to the scrubber, which caused several test runs to be discontinuous.
4.4.3.2. Pan Granulator. The only pan granulator in operation in
the AN industry was also tested by EPA. This facility (Plant D) uses a
6.75 kPa (27 in. W.G.) venturi scrubber to control emissions from the
granulator and an evaporator.
Uncontrolled emissions measured from the granulator were 1.34 g/kg
(2.68 Ib/ton). 8 The controlled pan granulator emissions could not be
measured alone because the scrubber also controlled evaporator emissions.
Nevertheless, controlled emissions were assumed to be from the granulator
because it constituted 98 percent of the uncontrolled emissions. The
total uncontrolled emissions were reduced from 1.37 g/kg (2.75 Ib/ton)
to 0.02 g/kg (0.04 Ib/ton), which was a 98.5 percent removal efficiency.48
During the test, no abnormalities in process operation were reported.
Cyclonic flow patterns were suspected at the scrubber inlet which resulted
in measured volumetric flow rates to be 10-15 percent lower than actual
volumetric flowrates. Since emissions calculations are based on volumetric
4-38
-------
flow rates, these too were believed to be low by 10-15 percent. Therefore,
the calculated efficiencies were expected to be lower than actual efficiencies,
4.4.4 Solids Finishing
EPA tested the uncontrolled and controlled emissions for four
solids finishing processes. The facilities tested included a high
density prill rotary drum cooler (Plant A), a pan granulator rotary drum
precooler (Plant D), a drum granulator rotary drum cooler (Plant E), and
a low density prill rotary drum predryer and dryer (Plant Z). As stated
in Section 4.3.5, these processes are considered together because of
similarities in operation and emissions. The particle size data from
each of these facilities are also similar, as can be seen in Figure 4-17
and Figures A-ll and A-12 in Appendix A.
Figure 4-18 presents the controlled emissions from each of these
solids finishing facilities. All of the scrubbers reduced the emissions
effectively because of the large size of the particles. Each scrubber,
except the one at Plant A, had approximately 98 percent removal efficiency.
The scrubber at Plant A had a 91 percent removal efficiency, which could
be attributed to a low particulate loading. Even though its scrubber
achieved a 99.5 percent removal efficiency, the controlled emissions for
the predryer and dryer at Plant Z were much higher than the other facilities.
The uncontrolled emissions for the predryer and dryer were also higher
than the other solids finishing facilities possibly due to higher airflows;
this may account for the higher controlled emissions.
At Plant A, a 1.0 kPa (4.0 in. W.G.) pressure drop spray chamber,
52
followed by a cyclone separator, is used to control cooler emissions.
The scrubber reduced emissions from 0.8 g/kg (1.6 Ib/ton) to 0.075 g/kg
(0.15 Ib/ton), for a removal efficiency of 91 percent. Plant A reported
no irregularities in operation or problems in sampling during the test.
Particle size data were not available due to particulate collection
problems.
At Plant D, a 1.4 kPa (5.6 in. W.G.) pressure drop spray scrubber
is used to control precooler emissions. The precooler at this plant
operates like coolers at other facilities, since it follows the solids
4-39
-------
Ib/ton
3 1.39 Ib/ton
)(1.30 Ib/ton
)1.21 Ib/ton
.15
.14
.13
.12
.11
.10
.O'J
4* .08
i
o .07
.06
.05
.04
.03
Plant
Facility
Product
.30
.28
.26
.24
.22
.20
.18
.16
.14
.12
.10
.08
.06
(
-
-
.
k
(
•
-
.
K
(
/
)
(
)
H
)
•1
)
Cy
«•
A 6 ta Z
Cooler Precooler Cooler Predryer-Dryer
High Density Prill Granule-Pan Granule-Drum Low Density Prill
Al'flow Rate 48,000 102,400 68,930 206,990
scf/ton
aOnly two test runs were accepted and both had the same emission rate.
Figure 4-18. Controlled emissions from solids finishing processes tested by EPA.
-------
formation process. Uncontrolled emissions from the precooler measured
18 g/kg (36 Ib/ton) and constituted 98 percent of the combined precooler-
chain mill emissions. Controlled emissions were measured at 0.12 g/kg
(0.23 Ib/ton) and were considered to be from the precooler because of
its proportion of the uncontrolled emissions. The scrubber showed a
99.4 percent removal efficiency. The plant operated normally and no
problems occurred during the testing.
A 3.3 kPa (13.1 in. W.G.) pressure drop entrainment scrubber is
used at Plant E to control granulator cooler emissions. The scrubber
reduced uncontrolled emissions from 8.6 g/kg (17.3 Ib/ton) to 0.03 g/kg
(0.07 Ib/ton), a 99.6 percent removal efficiency.57
During individual test periods at Plant E, variations in the
cooler operation occurred; the cooler outlet air temperature and the
cooler inlet and outlet solids temperature fluctuated. Problems also
occurred during sampling because of excessive particulate loadings at
the scrubber inlet, causing most of the sampling to be discontinuous.
In test run 3, controlled emissions were measured higher than uncontrolled.
A scrubber upset during the run may have caused some of these problems.
Therefore, since the results of test run 3 were nontypical of the first
two runs, only runs 1 and 2 were used in calculating the average.
Rotary drum predryer and dryer emissions at Plant Z are controlled
by a tray scrubber. The uncontrolled and controlled mass emissions from
these facilities were considerably higher than those at the other plants
(see Table 4-3 and Figure 4-18), possibly because of their high airflows.
EPA measured predryer-dryer uncontrolled emissions at 131 g/kg (262
Ib/ton). These emissions were reduced to 0.65 g/kg (1.30 Ib/ton) by the
CO
tray scrubber. This was a 99.5 percent removal efficiency.
Particle sizes for the uncontrolled emissions from the predryer and
dryer in Plant Z are presented in Appendix A. The controlled and uncontrolled
emissions for each facility were presented earlier but will not be used
4-41
-------
in Chapter 5 to characterize uncontrolled and controlled emissions from
solids finishing operations. These data are excluded because the high
airflow rates and emissions reported for these operations were uncharacteristic
of other tested solids finishing processes. However, even though the
emission rate is abnormally high, the particles emitted from the predryer
and dryer were large (99 percent by weight larger than 5 microns) and
similar to the particle size data from the emissions of the other solids
finishing facilities.
Plant Z operated normally during testing. Sampling problems occurred
when high grain loadings caused plugging of the nozzles. To counteract
this plugging, larger diameter nozzles were used, but the pumps were
unable to draw a sufficient flow through the nozzles to maintain isokinetic
sampling conditions. Low isokinetic sampling conditions would cause a
bias in the mass flowrate calculations, resulting in higher than actual
values. To compensate for the higher values, a second method (the area
ratio method), was used with the concentration method to calculate mass
flow rate. The average of these two was then used to obtain the mass
flow rate.
4-42
-------
4.5 REFERENCES
1. Memo from Bowen, M., Radian Corporation, to file. September 30, 1979.
Summary of scrubber pressure drops reported by industry.
2. Wade, W. A. and R. W. Cass. (The Research Corporation.) Ammonium
Nitrate Emission Test Report: C. F. Industries. (Prepared for
U. S. Environmental Protection Agency.) Research Triangle Park,
North Carolina EMB Report 79-NHF-10. November 1979. p. 54.
3. Trip report. Bornstein, M. I., GCA Corporation, to Noble, E. A.,
EPA: ISB. March 12, 1979. p. 5. Report of June 20, 1978 visit
to Mississippi Chemical Corporation in Yazoo City, Mississippi.
4. Letter and attachments from Davenport, T. H., Hercules, Inc., to
Goodwin, D. R., EPA: ESED. November 16, 1978. p. 4. Response to
Section 114 letter.
5. Memo from Anderson, C. D., Radian Corporation, to file. July 2,
1980. 34 p. Summary of information received from the ammonium
nitrate industry.
6. Joy Industrial Equipment Company. Type "D" Turbulaire Scrubber.
Bulletin S-l. Los Angeles, Western Precipitation Division, 1978.
p. 2.
7. York Research Corporation. Ammonium Nitrate Emission Test Report:
N-ReN Corporation. (Prepared for U. S. Environmental Protection
Agency.) Research Triangle Park, North Carolina. EMB Report 78-
NHF-5. May 1979. p. 49.
8. Theodore, L. and A. J. Buonicore, Industrial Air Pollution Control
Equipment for Particulates. Cleveland, CRC Press, 1976. p. 194.
9. Monsanto Enviro-Chem Systems, Inc. Mist Eliminators by Monsanto.
Bulletin Mo. 78-MON-7254. St. Louis, Monsanto Company, p. 2.
10. Search, W. J. and R. B. Reznik. (Monsanto Corporation.) Source
Assessment: Ammonium Nitrate Production. (Prepared for U. S.
Environmental Protection Agency.) Research Triangle Park, North
Carolina. Publication No. EPA-600/2-77-107i. September 1977.
p. 43.
11. Stern, A. C. (ed.). Air Pollution, Volume IV: Engineering Control
of Air Pollution. New York, Academic Press, 1977. p. 318.
12. Reference 9, p. 7.
13. Letter from Craska, P. D., Monsanto Enviro-Chem, to Rader, R. D.,
Radian Corporation. September 25, 1980. Information about collection
efficiency.
4-43
-------
14. Reference 10, p. 44.
15. Bethea, R. M. Air Pollution Control Technology. Atlanta, Van
Nostrand Reinhold Company, 1978. pp. 279-280.
16. The W. W. Sly Manufacturing Company. Impinjet Gas Scrubbers.
Catalog No. 151. Cleveland, The W. W. Sly Manufacturing Company.
p. 2.
17. Letter and attachments from Lerner, B. J., BECO Engineering, to
Sherwood, C. M., EPA: ISB.. February 2, 1978. p. 2. Information
about BECO V" scrubbers.
18. Reference 8, p. 193.
19. Reference 15, p. 275.
20. Industrial Gas Cleaning Institute. Basic Types of Wet Scrubbers.
Publication No. WS-3. Stamford, Industrial Gas Cleaning Institute,
June 1976. p. 2.
21. Roeck, D. R. and R. Dennis. (GCA Corporation.) Technology Assessment
Report for Industrial Boiler Applications: Particulate Collection.
(Prepared for U. S. Environmental Protection Agency.) Research
Triangle Park, North Carolina. Publication No. EPA-600/7-79-178h.
December 1979. p. 70.
22. Reference 15, p. 307.
23. Reference 8, p. 201.
24. Reference 20, p. 8.
25. Perkins, H. C. Air Pollution. New York, McGraw-Hill Book Company,
1974. p. 242.
26. Calvert, S. How to Choose a Particulate Scrubber. Chemical Engineering,
_84:54-68. Aguust 29, 1977. p. 63.
27. Reference 6, p. 3.
28. The Mcllvaine Company. The Mcllyaine Scrubber Manual, Volume 1.
Northbrook, Illinois The Mcllvaine Company, 1974. Chapter III, p.
65.0.
29. Reference 6, p. 5.
30. Reference 28, Chapter III, p. 70.0.
4-44
-------
31. Reference 15, pp. 297-298.
32. Reference 28, Chapter III, p. 71.0.
33. Reference 15, p. 295.
34. Reference 15, p. 19.
35. Reference 21, p. 49.
36. Kraus, M. N. Baghouses: Separating and Collecting Industrial
Dusts. Chemical Engineering. j36_(8):94-106. April 9, 1979.
37. Letter and attachments from Cayard, D. E., Monsanto Agricultural
Products, to Noble, E. A., EPA: ISB. December 4, 1978. 109 p.
Response to Section 114 letter from El Dorado plant, pp. 86-103.
38. Memo from Bowen, M. L., Radian Corporation, to file, December 17,
1980. References for emissions data from prill towers and granulators.
39. Reference 2, p. 13.
40. Reference 2, p. 49.
41. Letter and attachment from Lawson, R. A., Columbia Nitrogen Corporation,
to Miles, A. J., Radian Corporation. August 29, 1980. 15 p.
Process data sheets.
42. Wade, W. A., et al. (TRC Environmental Consultants, Inc.) Ammonium
Nitrage Emission Test Report: Columbia Nitrogen Corporation.
(Prepared for U. S. Environmental Protection Agency.) Research
Triangle Park, North Carolina. EMB Report 80-NHF-16. January
1981. pp. 8-12.
43. Reference 42, pp. 48-53.
44. Reference 42, pp. 37-40.
45. Hansen, M. D., et al. (Midwest Research Institute.) Ammonium
Nitrate Emission Test Report: Swift Chemical Company. (Prepared
for U. S. Environmental Protection Agency.) Research Triangle
Park, North Carolina. EMB Report 79-NHF-ll. July 1980. p. 2-26.
46. Reference 45, pp. 2-2 - 2-6.
47. Reference 45, p. 2-23.
48. Reference 7, pp. 20-21.
49. Reference 7, p. 40.
4-45
-------
50. Reference 45, p. 2-16.
51. Memo from Bowen, M. L., Radian Corporation, to file. December 17,
1980. References for emissions from solids finishing operations.
52. Reference 2, p. 55.
53. Reference 2, p. 21.
54. Reference 7, p. 54.
55. Reference 7, pp. 23-25.
56. Kniskern, Roger A., et al. (York Research Corporation.) Ammonium
Nitrate Emission Test Report: Cominco American, Inc. Beatrice,
Nebraska. (Prepared for U. S. Environmental Protection Agency.)
Research Triangle Park, N. C. EMB Report 79-NHF-9. April 1979.
p. 26.
57. Reference 53, p. 11.
58. Reference 42, pp. 18-23.
4-46
-------
5.0 MODEL PLANTS AND CONTROL ALTERNATIVES
Model ammonium nitrate plants, existing levels of control and
control alternatives are defined in this chapter. These model plants,
existing control levels and control alternatives are used for analysis
of the environmental and economic impacts associated with controlling
particulate emissions from ammonium nitrate plants.
Model plants are defined in Section 5.1 and existing levels of
control are discussed in Section 5.2. Section 5.3 presents control
options, while Section 5.4 presents the control alternatives being
considered and the emission parameters.
5.1 MODEL PLANTS
The model ammonium nitrate plants developed for this study are
presented in Table 5-1. The rationale for selection of the model plants
is discussed in Section 5.1.1. Process flowsheets and parameters for
the model plants are presented in Section 5.1.2 and Section 5.1.3,
respectively.
5.1.1 Rationale for Selection of Model Plants
Major solid production techniques currently in use in this industry
are high density prilling, low density prilling and granulation. The
emission sources included in a model high density prilling plant are the
prill tower and cooler. Model low density prilling plant emission
sources are the prill tower, predryer, dryer and cooler. Model granulation
plants have two sources of emissions, granulators and coolers. Model
plant production capacities range from 181 to 815 Mg/day (200 to 900
TPD) for low density prilling, and from 363 to 1089 Mg/day (400 to 1200
TPD) for both high density prilling and granulation plant';.
Plant sizes were selected from the distribution of existing plant
capacities to represent existing plants, as well as those expected to be
constructed, modified or expanded in the near future. The data used to
determine plant sizes, operating parameters and emissions levels were
5-1
-------
TABLE 5-1. MODEL AMMONIUM NITRATE PLANTS
Ul
ro
Model
Plant 4
H-1
H-2
H-3
L-1
1-2
L-3
G-1
G-2
G-3
! Process
High Density Prilling
High Density Prilling
High Density Prilling
Low Density Prilling
Low Density Prilling
Low Density Prilling
Granulation
Granulation
Granulation
Capacity
Mg/Day (TPD)
363 (400)
726 (800)
1089 (1200)
181 (200)
363 (400)
816 (900)
363 (400)
726 (800)
1089 (1200)
Emission Sources
Prill Tower, Rotary Drum Cooler
Prill Tower, Rotary Drum Cooler
Prill Tower, Rotary Drum Cooler
Prill Tower; Rotary Drum Predryer, Dryer, and Cooler
Prill Tower; Rotary Drum Predryer, Dryer, and Cooler
Prill Tower; Rotary Drum Predryer, Dryer, and Cooler
Rotary Drum Granulator, Rotary Drum Cooler
Rotary Drum Granulator, Rotary Drum Cooler
Rotary Drum Granulator, Rotary Drum Cooler
-------
123
obtained from an industry survey, source testing and available literature. * '
The model plants represent plants of small, medium and large capacities.
Although AN plants exist with greater capacities than the largest selected
for modeling, their capacities were developed incrementally over several
years; therefore, no model plants were chosen to represent those capacities.
A few plants have prill towers producing both high and low density
prills. However, there was insufficient information available to determine
what the division of operating hours or production would be between
products. Therefore, it was assumed that each model plant would produce
a specific product only.
5.1.2 Process Flow Sheets
Process flow sheets for each of the model plants selected are
presented in Figures 5-1 to 5-5. Figure 5-1 represents the high density
prilling process. Figure 5-2 represents the low density prilling process,
and Figures 5-3 to 5-5 represent the granulation process. These flow
sheets present only the solids formation and finishing part of the plant
downstream of the solution process. The process equipment and parameters
shown for all the model plants are typical of the current industry
practice and are based on a survey of the industry.
All sizes of prilling plants have flow sheets similar to the one
shown. Rotary drum granulators usually come in a fixed size, 400 TPD.
For plants with larger capacities, companies build multiple, parallel
400 TPD trains, as shown in Figures 5-3 to 5-5.
In each of the model plants, gaseous ammonia and a 56 percent
nitric acid solution (by weight) are combined in a neutral izer to form
an 83 percent solution of ammonium nitrate. This solution is then
concentrated to a 96.5 to 99+ percent melt. Solids are then formed by
prilling or granulation. After the formation process, the solids are
dried, if needed, and cooled. The product may also be coated to prevent
caking. The solids are then either bagged or bulk shipped. Additional
process parameters are discussed in the following section.
5-3
-------
0
i
CONTROL
EQUIPMENT
4 >
<
SOLUTION
FORMATION &
CONCENTRATION
T
99.8% AN MELT <
0.2% H2O
SOLUTION
AIR-2-
en
i
BYPASS
VENT
38*0
>2.2% H20
PRILL
TOWER
CONTROL
EQUIPMENT
113° C SOLID AN
0.2% H2O
63° C
1.4% H20
27° C
0.8% H2O <
COOLER
43° C SOLID AN
0.2% H2O _
SCREENS
REFRIGERATED
AIR AT 18'C
OFFSIZE RECYCLE
43° C
0.2% H2O
COATER
1.5%
COATING
SOLID AN.
,EXHAUST
STREAM
27° C
0.8% H2O
BULK
LOADING
Figure 5-1. High density prill plant,
-------
on
©
O
SOLUTION
FORMATION &
CONCENTRATION
I 38'C
|2.2%H2O
96.5% AN MELT
£
PRILL
TOWER
77'C SOLID AN
2.5% H2O
AIR IN
93° C
OFFSIZE RECYCLE
AIR IN
71" C
AIR IN
21" C
35° C
0.2% H20
SOLID AN
SCREENS
EXHAUST STREAM
0.8%
BAGGED
PRODUCT
rc <
BAGGING
BULK
LOADING
27° C
1.5% COATING
Figure 5-2. Low density prill plant.
-------
en
t
01
0
4 43° C
>2.0%H20
SCRUBBER ^Jt-^^
MAKEUP
ISCRUBBER
WATER
46'C
1.8% H2O
REFRIGERATED
AIR AT 10° C
SCRUBBER
LIOUID
STORAGE
TANK
S 2.0% H2O
DRUM
GRANULATOR
99.8% AN SOLID
35° C
99.8% AN
SOLUTION
FORMATION &
CONCENTRATION
REFRIGERATED
AIR AT 10" C
27" C
0.8% H,
> EXHAUST STREAM
> 27° C
1.8% H2O
BULK
LOADING
Figure 5-3. 363 Mg/day (400 TPD) granulation plant.
-------
en
BAGGING
EMISSION
POINT
SCRUBBER
LIQUOR
STORAGE
TANK
REFRIGERATED
AIR AT 10° C
Figure 5-4. 726 Mg/day (800 TPD) granulation plant.
-------
en
i
Co
©
4S'C
16% MjO
7^
s» y»
— *f DRUM
|— «^ GRANULATI
« 1 CRUSHER
',.
*HP |
COOIBOL
EQUIPMENT
— U — 1 »-c ,
u I M.tH AN SOLID <
3RJ
OVERS12E
UNDERSUE
f
SCREENS
1
n-c
AN SOLID
«
COO
,,„
1
EXHAUST STREAM
REFRIGERATED
AIR AT WC
Figure 5-5. 1089 Mg/day (1200 TPD) granulation plant.
-------
5.1.3 Process Parameters
Operating hours, raw material requirements, and base energy require-
ments for the model plants are presented below. These model plant
parameters are based upon a survey of the industry and source test data.
The industry survey indicated a wide range of operating hours (less
than 100 days/yr to 360 days/yr); however, these were influenced by
market demand. All the model plants are assumed to operate 7728 hours
per year, based on a 7 day, 24 hour/day, 46 week operation, which
allows 6 weeks for scheduled and nonscheduled downtime.
The raw material requirements, ammonia, nitric acid, and coating
material, for the model plants are presented in Table 5-2. Raw material
requirements are the same for each plant of the same size, regardless of
what product is produced, high density prills, low density prills or
granules.
The greatest energy requirement for ammonium nitrate plants is the
steam used to concentrate the 83 percent AN solution to the proper melt
concentration. Electricity requirements for rotary equipment (granulators,
predryers, dryers, and coolers), conveying equipment and pumps are small
in comparison to the steam requirements. As a result, the energy require-
ments per unit of solid produced are approximately the same for all the
model plants, approximately 5.12 GJ/Mg (4.4 x 106 Btu/ton) of solids
4
produced. This value includes the energy requirements for solution
production and concentration, solids formation, finishing and handling,
but does not include energy requirements for the concentration of scrubber
liquors. Since the granulator scrubber is normally considered to be
process equipment, the energy needed for the concentration of the granulator
scrubber liquor must be included. The additional energy needed to
concentrate this scrubber liquor is 0.272 GJ/Mg (2.34 x 105 Btu/ton) of
ammonium nitrate produced. Plant energy requirements, alorg with impacts
due to the control equipment, are presented in detail in Chapter 6.
5-9
-------
TABLE 5-2. RAW MATERIAL REQUIREMENTS FOR THE
MODEL AMMONIUM NITRATE PLANTS3,a
U1
Plant
Mg/day
363
726
1089
Size
TPD
400
800
1200
Ammo
6g/yr
24
47
71
.0
.9
.9
nia
lo3
26.
52.
79.
TPY
5
8
3
Nitric
Gg/yr
88.8
177.7
266.5
Acid5
10 J TPY
97
195
293
.9
.9
.8
Coatimj
Gg/yr
3.6
7.2
10.8
.AS
lo3
4
7
11
ent
TPY
.0
.9
.9
aBased on plant production capacity and 7728 operating hours per year,
56 percent nitric acid in water.
-------
5.2 DETERMINATION OF EXISTING CONTROL LEVELS
Existing levels of control are used as a reference point in determining
the impacts of control alternatives and options. This section presents
the existing levels of control selected for the ammonium nitrate industry
and the procedures used to select these levels. These levels were
determined after a review of the emission level requirements and the
degree of control imposed by State Implementation Plans (SIP's) and
other regulations. This section is divided into two subsections:
Subsection 5.2.1 presents a discussion of existing emission limitations.
Subsection 5.2.2 discusses the existing degree of control found in the
industry, and discusses the rationale for selection of controls to meet
existing levels of control for each source.
5.2.1 Existing Emission Limitations
Twenty-three states contain plants that manufacture AN solids.
Table 5-3 presents a summary of process weight particulate emission
standards and maximum allowable particulate concentrations for these
states. These regulations fall under the heading of "industrial source
emissions". Only North Carolina has a specific regulation applying to
chemical fertilizers. The regulation presented for California applies
to the Orange County Air Pollution Control district, which accommodates
the only AN solids production plant in California. Emission requirements
vary significantly from state to state due to differences in process
weight regulations, sampling techniques, source definition and enforcement
methods.
Opacity regulations vary, but 17 of 23 states require emissions to
be less than 20 percent opacity. This is the most stringent opacity
regulation presently in effect. Four states allow a 40 percent opacity,
while the remaining state, Illinois, adopted a 30 percent opacity regulation.
Discussion with plant and regulatory personnel indicate that
opacity limits are frequently the most difficult to comply with. In
some cases, regulatory agencies cited an opacity violation although
particulate emission control was greater than that required to meet the
mass emission level.
5-11
-------
TABLE 5-3. EMISSIONS STANDARDS AFFECTING AMMONIUM NITRATE PLANTS
Opacity
State (percent)
Alabama
Arizona
Arkansas
California0
Florida
Georgia
mino1sd
Indiana
Iowa
Kansas
Louisiana
Minnesota
Mississippi
Missouri
Nebraska
New Mexico
North Carolina
Oklahoma
Tennessee
Texas
Utah
Washington
Wyoming
20
10
20
20
20
20
30
40
40
20
20
20
40
20
20
20
20
20
20
20
20
20
Allowable parti- Allowable parti- Allowable parti- Allowable partl-
culate emissions culate emissions culate emissions culate emissions
1n Ib/hr for 1n kg/hr for In Ib/hr for In kg/hr for
Grains/ Grans/ Process weight regulation 200 ton/day 181 Mg/daya 1200 ton/day 1089 Mg/day
ft m Pi30 ton/hr P>30 ton/hr Process Process Process Process
3.59(P)°'62
4.10(P)°'67
O.Q722(P)°'78
3.59(P)°'6Z
3.59(P)°'62
2.54(P)°-534
4.10(P)°'67
4.10(P)0>67
4.10(P)°'67
0.3 0.69 4.10(P)°'67
3.59(P)°-6Z
4.10(P)°'67
0.3 0.69 4.10(P)°-67
4.10{P)°-67
4.10(P)°'67
9.377(P)°-3067
0.3 0.69 4.10(P)°'67
0.25 0.58 3.59(P)°'62
312{p)0.985
Under Development
0.1 0.23 Under Development
3.59(P)°'62
17.3KP)0'16
(55.0(P)OJ1)-40
1.29(P)°'43
17.31(P)°'16
17.31(P)°'16
24.8(P)°'16
(55.0(P)OJI)-40
(55.0(P)°-n)-40
(55.0(P)0>11)-40
(55.0(P)M1HO
17.31(P)°'16
(55.0(P)°'11HO
(55.0{P)°'n)-40
(55.0(P)°-n)-40
(55.0(P)0<11)-40
(55.0(P)0-11)-40
17.31(P)°'16
25.4(P)°-287
17.31(P)°'16
13.37
16.97
120.26
26.74
13.37
13.37
7.88
16.97
16.97
16.97
16.97
13.37
16.97
16.97
16.97
16.97
17.96
16.97
13.39
25.18
13.37
6.079
7.72
54.68
12.14
6.079
6.079
3.58
7.72
7.7Z
7.72
7.72
6.079
7.72
7.72
7.72
7.72
8.17
7.72
6.079
11.45
6.079
32.37
44.58
259.91
13.15
32.37
32.37
20.52
44.58
44.58
44.58
44.58
32.37
44.58
44.58
44.58
44.58
31.13
44.58
32.37
78.06
32.37
14.72
20.27
118.18
5.97
14.72
14.72
9.33
20.27
20.27
20.27
20.27
14.72
20.27
20.27
20.27
20.27
14.15
20.27
14.72
35.49
14.72
aBased on 24-hour operatf in.
bProcess weight regulations for Arkansas apply to production rates of 100
-------
Limits on particulate emissions from AN solids production facilities
are usually based on the plant's production rate. Twenty-one of 23
plants are under process weight regulations, which vary between states
(Table 5-3).
Another variation in the state emission regulations is the definition
of the word "source". Most states consider each stack or process as a
source; one state, Arkansas, considers the combined emissions of an
entire plant as a source.
State air pollution standards may specify the sampling method for
determining compliance with the emission standard. Specified sampling
procedures include EPA's Method 5, the American Society of Mechanical
Engineers' Performance Test Code (PTC) 27, and other procedures. The
collection efficiencies of these sampling procedures can vary, depending
upon factors such as the type of filter used, and the sample recovery
and analytical procedures. Even when two state emission standards are
identical, one standard can be more stringent if its sampling procedure
collects a higher percentage of particulates.
The sampling and analytical procedure used by EPA to determine
particulate emissions from ammonium nitrate plants during this study was
developed to include condensible particulate emissions. The EPA method
is a "modified" Method 5 described in Appendix B (AN-MOD 5). This
modified version was developed because it was suspected that some ammonium
nitrate particulates were being vaporized by the heated probe used in
sample collection. In addition, Method 5 could not collect the small
particulates formed by the recombination of ammonia and nitric acid
fume. Because of differences in testing procedures, EPA test results
and data from AN industry tests do not necessarily correlate.
There are several problems inherent in the use of SIP levels to
determine the existing level of control for the AN industry. First,
SIP's are usually enforced via opacity observations rather than actual
measurement of emissions. No correlation between opacity and mass
emissions has been made in the AN industry. Second, different test
methods are used by the states to demonstrate compliance, and there is
5-13
-------
insufficient data to assess the magnitude of the differences between
state test methods and the newly developed AN-MOD 5.
A new ammonium nitrate plant could be built in any state. Because
it is difficult to predict where a new ammonium nitrate plant might be
built, the emission standards for the states which presently contain AN
plants were considered in the determination of the existing level of
control. In addition, variances between monitoring methods and degree
of enforcement were reviewed.
Table 5-4 was developed to characterize allowable emissions by
plant size and location. From this table it can be seen that a new
source would have to meet process weight regulations varying from 0.17
to 1.5 g/kg (0.34 to 3.0 Ib/ton), excluding Arkansas, depending upon
production rate and the state it is located in. It should be noted that
fewer emissions are allowed as production increases.
To facilitate the selection of a representative existing level of
control, both straight and weighted averages of the SIP's were determined.
Arkansas was excluded because it utilizes a different definition of
source. Weighted averages were determined for the total solid ammonium
nitrate industry and for each of the three types of solids forming
processes, high density prilling, low density prilling and granulation.
The results showed agreement between the straight average, which ranged
from 0.41 to 0.94 g/kg (0.82 to 1.88 Ib/ton), and the weighted average
for the total solids industry, which ranged between 0.4 to 0.94 g/kg
(0.8 to 1.88 Ib/ton). However, the weighted averages for the three
solids forming processes showed differences between processes ranging
from 0.37 to 1.16 g/kg (0.74 to 2.32 Ib/ton). (See Table 5-4.)
A total of 33 plants located in 21 states were considered in Table
5-4. This is a small population which makes the weighted averages
sensitive to low and high SIP levels. A survey of ammonium nitrate
plants showed that most states contain a single ammonium nitrate production
facility. A state containing several plants significantly affects any
weighted averages by putting more emphasis on that state's SIP. Therefore,
a straight average, not individual weighted averages, of the SIP's was
5-14
-------
TABLE 5-4. ALLOWABLE EMISSIONS BY PLANT SIZE
PLANT SIZE
STATE
Alabama
Arizona
Arkansas*
California
florida
Georgia
Illinois
Indiana
Iowa
Kansas
Louisiana
Minnesota
Missouri
Mississippi
Mecraska
New Mexico
North Carolina
Oklahoma
Tennessee
Texas
Wyoming
Straight Average
TOTAL
Weighted Average
Low Density Prill
Tower Weighted
Average
Hign Density Prill
Tow;r Weighted
Average
GRANULATION
Weighted Average
(200 TPO)
lb/ ton
1.604
2.037
14.071
1.307
1.604
1.604
.946
2.037
2.037
2.037
2.037
1.604
2.037
2.037
2.037
2.037
2.156
2.037
2.037
3.022
1.604
1.382
1.884
1.894
1.797
2.32
-1ST lfg/0
9/1=9
.802
1.013
7.035
.6535
.302
.802
.473
1.018
1.018
1.018
1.013
.802
1.013
1.013
1.018
1.018
1.078
1.018
1.318
1.511
.802
.941
.942
.947
.399
l.TS
(400 TPO)
Ib/ton
1.233
1.620
9.433
.793
1.233
1.233
.685
1.S20
1.620
1.620
1.620
1.233
1.620
1.620
1.620
1.620
1.333
1.620
1.620
2.991
1.233
1.498
1.480
1.490
1.375
2.017
362 Mg/D
gAg
.616
.810
4.716
.397
.516
.616
.343
.810
.810
.810
.310
.616
.810
.810
.810
.810
.667
.810
.810
1.49
.616
.749
.74
.745
.688
1.009
(800 TPO)
Ib/ton
.910
1.227
6.323
.466
.910
.910
.496
1.227
1.227
1.277
1.277
.910
1.227
1.227
1.227
1.227
.325
1.227
1.227
2.085
.910
1.108
1.089
1.094
1.015
1.475
724 Mg/D
gAg
.455
.613
3.161
.233
.455
.455
.248
.613
.613
.613
.613
.455
.613
.613
.613
.613
.413
.613
.613
1.042
.455
.554
.544
.547
.507
.737
(1200 TPO)
Ib/ton
.647
.892
5.004
.343
.647
.647
.410
.892
.892
.392
.892
.647
.892
.392
.892
.392
.623
.392
.392
1.561
.547
.816
.795
.797
.741
1.086
1089 Mq/D
g/kg
.323
.446
2.502
.172
.323
.323
.205
.446
.446
.446
.446
.323
.446
.446
.446
.446
.312
.446
.446
.780
.323
.408
.393
.398
.370
.543
Arkansas not included in averages because emissions are for entire plants, not single sources.
5-15
-------
selected to determine the existing level of control. A survey of production
levels for the solid ammonium nitrate industry indicated that an average
plant produces 453 Mg/Day (500 TPD). Based on a straight average of the
SIP's, a plant of this size would be required to meet an emission level
of 0.7 g/kg {1.4 Ib/ton) for each source. This emission level will be
used as the basis for selecting the existing level of control for all of
the sources.
5.2.2 Determination of Existing Emission levels for Individual Sources
In this section, the existing level of control selected for each
source being studied is presented. Uncontrolled emissions and the
existing degree of control practiced by industry, which are summarized
in Table 5-5, are also discussed. The existing level of control and
corresponding control equipment selected for the various sources are
presented in Table 5-6.
5.2.2.1 High Density Prill Towers. Based upon the industry data
summarized in Table 5-5, uncontrolled emissions from high density prill
towers range from 0.81 to 2.74 g/kg (1.63 to 5.48 Ib/ton). The one high
density prill tower tested by EPA had uncontrolled emissions of 1.6 g/kg
(3.2 Ib/ton). These uncontrolled emissions levels indicate that most
prill towers would be required to utilize some degree of control under
SIP's. Table 5-5 Indicates that 15 percent utilize low efficiency
scrubbers and 55 percent utilize collection hoods in conjunction with
wetted fibrous filter scrubbers. The controls used are more effective
than necessary to meet the range of SIP process weight regulations
shown. (The extra degree of control may be attributed to the opacity
requirements of the SIP's.)
Based on the existing degree of control practiced by industry, a
new high density prill tower would require some degree of control. For
the purpose of this analysis, an existing level of control of 0.7 g/kg
(1.4 Ib/ton) was chosen for high density prill towers (Table 5-6).
This represents the allowable SIP level for an average size source. In
addition, it was assumed that uncontrolled emissions for a high density
5-16
-------
TABLE 5-5. UNCONTROLLED EMISSIONS AND EMISSIONS CONTROL TECHNIQUES
FOR SOLID AMMONIUM NITRATE PROCESSING FACILITIES
Uncontrolled Emissions
No. of Ammonium Nitrate g/kg (Ib/ton) Tray No.
Process Facilities EPA Industry UFFS* Entrapment Cyclone Venturl Type Mechanical Other None Info.
in
i
i— >
Solids Formation
High Density 20
Prill Tower
Low Density 18
Prill Towei1
Drum 6
Granulators.
Pan 1
Granulator
Solids Finishing
Predryers , 76^
Dryers ,
Cooler
1.6
(3.2)
0.39
(0.78)
147.2
(294.6)
1.34
(2.68)
0.83-18
(1.66-36)
0.82
(1.63
0.21
(0.42
138
(277
No
3.2
(6.4
- 2.74 11 - .11.43-
- 5.48)
- 0.69 9 1 ..... iz .
- 1.38)
-152 - 8 - - - - ...
- 305)
Data - - .1...-.
- 35.2 1 7 37 - 7 12 2 3 3
- 70.5)
a. Includes smog towers, knockout chambers, spray towers,-Internal controls, or wetted mesh pads.
b. Total nuirber of solids finishing processes with available data. Some will have more than one control device or may be connected In series to a
single control device.
*MFFS • Wetted Fibrous Filter Scrubber
-------
TABLE 5-6. EXISTING LEVEL OF CONTROL (ELOC)
EMISSIONS AND CONTROL EQUIPMENT
FOR AMMONIUM NITRATE FACILITIES
Emission
source
Existing control
equipment
ELOC
Ib/ton
ELOC
g/kg
High density
prill tower
Low density
prill tower
Granulator
Solids finish-
ing
Two-tray Scrubber
AP = 2.7 kPa (11" W.G.)
None
Entrainment Scrubber
AP = 3.5 kPa (14" W.G.)
Tray Scrubber
AP = 0.75 kPa (3" W.G.)
1.4
1.4
0.5
1.4
0.7
0.7
0.25
0.7
5-18
-------
tower would be 1.55 g/kg (3.1 Ib/ton), based upon the EPA test. With
this level of uncontrolled emissions, a high density prill tower requires
a low efficiency control device to meet the chosen emission level.
5.2.2.2 Low Density Prill Towers. Industry data summarized in
Table 5-5 indicate that uncontrolled emissions for low density prill
towers range from 0.21 to 0.69 g/kg (0.42 to 1.38 Ib/ton) and that the
majority of low density prill towers are uncontrolled. It is expected
that new low density prill towers would have the same range of uncontrolled
emissions and would be capable of meeting the applicable SIP's. The
existing level of control chosen, 0.7 g/kg (1.4 Ib/ton), represents the
allowable SIP level for an average sized source. It is assumed that a
new low density prill tower would not require any control equipment to
achieve this emission level.
5.2.2.3 Granulators. Results of an EPA test show uncontrolled AN
emissions of 147.2 g/kg (294.6 Ib/ton) for granulators. A comparison of
uncontrolled emissions from granulators and even the most lenient SIP's
indicates that removal efficiencies of greater than 99 percent would be
required. In addition, process economics dictate the use of a control
device to recover the large amounts of product that would otherwise be
lost. A survey of industry indicated that all existing granulators
utilize wet scrubbers to control emissions. With these considerations
in mind, it is unlikely that a new granulator will be built without some
type of control device.
The existing level of control for granulators was set at 0.25 g/kg
(0.5 Ib/ton), based on an EPA test of a typical granulator scrubber
(Table 5-6). This degree of control is greater than required by most
SIP's; however, it is typical of existing industry practice.
5.2.2.4 Solids Finishing. Solids finishing includes granulator
coolers, high density prill coolers, and low density predryers, dryers,
and coolers. Rotary drum coolers, dryers and predryers have the same
configuration no matter where they are applied. However, uncontrolled
emissions from these rotary units do vary by the type of product handled.
5-19
-------
All rotary coolers, dryers and predryers installed in the past ten years
have been equipped with some form of control device. Wet scrubbers are
the predominate control device in the industry. Three fluid bed coolers,
one fluid bed dryer and one fluid bed predryer have been constructed
over the last 11 years. Two of the three fluid bed coolers are uncontrolled.
Uncontrolled emissions for solids finishing operations are reported
by industry to vary from 3.2 to 35.2 g/kg (6.4 to 70.5 Ib/ton) and have
been measured by EPA from 0.83 to 18 g/kg (1.66 to 36 Ib/ton). With
these high emissions levels, the majority of solids finishing operations
would require some form of control to meet SIP's. Table 5-5 indicates
that the majority of solids finishing operations are controlled. For
the purpose of this analysis it was assumed that all solids finishing
operations would have an existing level of control of 0.7 g/kg (1.4
Ib/ton) based upon the average SIP's (Table 5-6). In addition, it was
assumed that, based upon an average of EPA tests, the uncontrolled
emissions for a typical solids finishing operation would be 5.4 g/kg
(10.8 Ib/ton). With this level of uncontrolled emissions, any solids
finishing operation would require a moderately efficient scrubber to
meet the chosen emission level.
5.3 CONTROL OPTIONS
This section presents an analysis of the individual emission sources
requiring control. Discharge parameters from these sources are presented
for the various model plants, and control equipment is selected to
reduce emissions over the existing level of control. High density and
low density prill towers are discussed in Sections 5.3.1 and 5.3.2,
respectively. Section 5.3.3 discusses granulators, and Section 5.3.4
discusses solids finishing equipment.
5.3.1 High Density Prill Towers
The high density prill tower is usually controlled to meet state
implementation plan (SIP) emission levels. A tray scrubber was chosen
for the existing control device, as shown in Table 5-6. To meet a more
stringent limitation, a fume collection hood, followed by a wetted
fibrous filter scrubber, was selected (Option 1). Only the portion of
5-20
-------
the tower airflow having the most concentrated emissions is treated with
the control device in this system. Another option selected was using
the wetted fibrous filter scrubber to control the full tower airflow
(Option 2). A third option was also selected and is the same as Option
2, except that the net tower airflow is reduced through the use of
process modifications (Option 3). One plant in the industry operates in
such a manner. This plant was originally designed to operate in the
conventional manner, with full airflow. By modifying the process to
handle a reduced airflow, the size and cost of control equipment were
greatly reduced. Discharge parameters for high density prilling plants
are presented in Tables 5-7a to 5-7c.
Control equipment is located on top of the prill tower in all cases
except the full airflow case (Option 2). A scrubber that could handle
the full tower airflow would be too large to fit on top of the prill
tower. Therefore, the scrubber is located at ground level and tower
emissions are ducted down to it.
5.3.2 Low Density Prill Towers
The low density prill tower is typically uncontrolled. Therefore,
no control was selected for the existing case. One system for controlling
particulate emissions from low density prill towers includes a fume
collection hood, followed by a wetted fibrous filter scrubber (Option
1). With this system a selected portion of tower airflow emissions
bypasses the control device. Another option chosen involves using the
wetted fibrous filter scrubber to control the full tower airflow (Option 2).
The discharge parameters for low density prilling plants are presented
in Tables 5-8a to 5-8c.
The control equipment is located on top of the prill tower for all
cases except the full airflow case for the same reasons as discussed
above in 5.3.1.
5.3.3 Granulate rs
The granulator control device is the same for all control alternatives.
All granulators in the industry are currently controlled with the same
type of device (an entrainment scrubber), and if properly installed and
5-21
-------
TABLE 5-7a. EMISSION PARAMETERS: AMMONIUM NITRATE HIGH DENSITY
PRILLING PLANT - 363 Mg/Day (400 TONS PER DAY)
en
ro
Emission Type of
Source Discharge
Prill Tower Stack
Prill Tower" Stack
Prill Tower Stack
Prill Towerc Stack
Cooler Stack
Cooler Stack
Level of
Control
Existing
Option 1
Option 2
Option 3
Existing
Option 1
Participate
Type of Emission Rate
Control gralns/s
Tray
Scrubber
11" AP
Bypass
Collection
Hood/HFFSb
14" AP
14" AP HFFSb
14" AP HFFSb
Tray
Scrubber
Entrapment
45.4
14.47
1.73
3.24
3. 24
45.4
3.24
grams/s
2.94
0.94
0.11
0.21
0.21
2.94
0.21
Height of
Discharge
feet
203.0
191.0
220.0
60.0
222.0
60.0
60.0
meters
61.87
5B.22
67.06
18.29
67.67
18.29
18.29
Stack
Diameter
feet
395.0
394.5
4.0
206.0
4.5
3.0
3.0
meters
391.52
301.37
1.22
201.83
1.37
0.91
0.91
Stack Total Air
Temperature Flow Rate
*F K scfm
100 310.62 155,000
100 310.62 124.000
31 ,000
100 310.62 155,000
100 310.62 39,000
115 318.94 20,000
115 318.94 20,000
Std HJ/mln
4,389.60
3,511.68
877.92
4,389.60
1, 104.48
566.40
566.40
Air Velocity
per Stack
ft/s
43.9
43.3
41.1
45.7
41.0
47.2
47.2
meters/s
13.37
13.21
12.53
13.93
12.50
14.39
14.39
a20 percent of the airflow goes through collection hood; 87 percent of the emissions goes through collection hood.
bWetted fibrous filter scrubber.
""Reduced flow -- 25 percent of baseline.
-------
TABLE 5-7b. EMISSION PARAMETERS: AMMONIUM NITRATE HIGH DENSITY
PRILLING PLANT - 726 Mg/Day (800 TONS PER DAY)
ro
co
Emission
Source
Prill Tower
Prill Tower3
Prill Tower
Prill Tower
Cooler
Cooler
Type of
Discharge
Stack
Stack
Stack
Stack
Stack
Stack
Level of
Control
Existing
Option 1
Option 2
Option 3
Existing
Option 1
Partlculate
Type of Emission Rate
Control grains/s
Tray 90.7
Scrubber
11" AP
Bypass 28.93
Collection 3.47
Hood/WFFSb
14" AP
14" AP MFFSb 6.48
14" AP MFFSb 6.48
Tray 90.7
Scrubber
Entrapment 6.48
Scrubber
13" AP
granis/s
5.88
1.88
0.23
0.42
0.42
5.88
0.42
Height of
Discharge
feet
205.0
195.0
224.0
60.0
225.0
80.0
80.0
nieters
62.48
59.44
68.28
18.29
68.58
24.38
24.38
Stack
Diameter
feet
496.0
396.0
5.5
496.0
6.0
5.0
5.0
meters
491.83
391.83
1.68
491.83
1.83
1.52
1.52
Stack Total Air
Temperature Flow Rate
°F K scfm
100 310.62 310,000
100 310.62 248,000
62,000
100 310.62 310,000
100 310.62 78,000
115 318.94 40,000
115 318.94 40,000
Std H^/min
8,779.20
7,023.36
1.755.84
8,779.20
2.208.96
1.132.80
1,132.80
Air Velocity
per Stack
ft/s
45.7
48.8
43.5
45.7
46.0
33.97
33.97
meters/s
13.93
14.86
13.26
13.93
14.02
10.35
10.35
a20 percent of the airflow goes through collection hood; 87 percent of the emission goes through
Wetted fibrous filter scrubber.
cReduced flow - 25 percent of baseline.
hood.
-------
TABLE 5-7c. EMISSION PARAMETERS: AMMONIUM NITRATE HIGH DENSITY
PRILLING PLANT - 1089 Mg/Day (1200 TONS PER DAY)
en
ro
Emission Type of
Source Discharge
Prill Tower Stack
Prill Tower* Stack
Prill Tower Stack
Prill Tower0 Stack
Cooler Stack
Cooler Stack
Level of
Control
Existing
Option 1
Option 2
Option 3
Existing
Option 1
Participate Height of Stack
Type of Emission Rate Discharge Diameter
Control gratns/s
Tray
Scrubber
11" AP
Bypass
Collection
Hood/WFFSb
14" AP
14" AP WFFSb
14" AP WFFSb
Tray
Scrubber
Entrapment
Scrubber
13" ftp
136.1
43.41
5.20
9.72
9.72
136.1
24.3
grams/ s feet meters feet meters
8.82 205.0 62.48 696.0 691.83
2.81 195.0 59.44 596.0 591.83
0.34 222.0 67.67 294.5 291.37
0.63 60.0 18.29 696.0 691.83
0.63 223.0 67.97 295.0 291.52
B.B2 90.0 27.43 6.0 1.83
1.58 90.0 27.43 6.0 1.83
Stack Total Air Air Velocity
Temperature Flow Rate per Stack
*F K scfm
100 310.62 465,000
100 310.62 372,000
93,000
100 310.62 465,000
100 310.62 116.000
115 318.94 60,000
115 318.94 60,000
Std H3/m1n ft/s
13,168.80 45.7
10,535.04 43.9
2,633.76 48.8
13,168.80 45.7
3.285.12 49.3
1.699.20 35.4
1.699.20 35.4
meters/s
13.93
13.37
14.86
13.93
15.01
10.7?
10.79
a20 percent of the airflow goes through collection hood; 87 percent of the emission goes through collection hood.
Wetted fibrous filter scrubber.
cReduced flow — 25 percent of baseline.
-------
TABLE 5-8a. EMISSION PARAMETERS: AMMONIUM NITRATE LOW DENSITY
PRILLING PLANT - 181 Mg/Day (200 TONS PER DAY)
Emission
Source
Prill Tower
Prill Tower"
Prill Tower
Predryer
1* Predryer
ro
en
Dryer
Dryer
Cooler
Cooler
Type of
Discharge
Stack
Stack
Stack
Stack
Stack
Stack
Stack
Stack
Stack
Level of
Control
Existing
Option 1
Option 2
Existing
Option 1
Existing
Option 1
Existing
Option 1
Type of
Control
Uncontrolled
Bypass
Co 1 1 ei M oil
Hood/WFFSb
14"APHFFs''
Tray
Scrubber
Entralnment
wet scrubber
Tray
Scrubber
Entralnment
wet scrubber
Tray
Scrubber
Entralnment
wet scrubber
Participate
emission rate
gralns/s
22.7
7.23
0.87
1.62
22.7
1.62
22.7
1.62
22.7
1.62
grams/s
1.47
0.47
0.06
0.11
1.47
0.11
1.47
0.11
1.47
0.11
Height of
discharge
feet
189.0
IR8.0
218.0
60.0
50. n
50.0
50.0
50.0
50.0
50.0
meters
57.61
57.30
66.45
18.29
15.24
15.24
15.24
15.24
15.24
15.24
Stack Stack Total Air
diameter temperature flow rate ,
feet meters °F
30 3.5 39 1.07 100
3P 3.0 30 0.91 100
3.0 0.91
6.0 1.83 100
2.0 0.61 135
2.0 0.61 135
2.0 0.61 135
2.0 0.61 135
2.0 0.61 115
2.0 0.61 115
K scfm
310.62 76.000
310.62 61,000
15,000
310.62 76.000
330.04 10,000
330.04 10,000
330.04 10,000
330.04 10,000
318.94 10.000
318.94 10.000
Std M'/mln
2152.32
1727.52
424.80
2152.32
283.20
283.20
283.20
283.20
283.20
283.20
Air velocity
j»r stack
ft/s
43.9
48.0
35.4
44.8
53.0
53.0
53.0
53.0
53.0
53.0
metcrs/s
13.3H
14.62
10.79
13.66
16.15
16.15
16.15
16.15
16.15
16.15
*20 percent of the total airflow goes through collection device; 80 percent of the emissions go through collection device.
bHetted Fibrous Filter Scrubber
-------
TABLE 5-8b. EMISSION PARAMETERS: AMMONIUM NITRATE LOW DENSITY
PRILLING PLANT - 363 Mg/Day (400 TONS PER DAY)
Emission
Source
Prill Tower
Prill Tower"
Prill Tower
Predryer
I Predryer
r\j
en
Dryer
Dryer
Cooler
Cooler
Type of
Discharge
Stack
Stack
Stack
Stack
Stack
Stack
Stack
Stack
Stack
Level of
Control
Existing
Option 1
Option 2
Existing
Option 1
Existing
Option 1
Existing
Option 1
Type of
Control
Uncontrolled
Bypass
Collection
Hood/WFFSb
14" AP WFFSb
Tray
Scrubber
Entralnment
wet scrubber
Tray
Scrubber
Entralnment
wet scrubber
Tray
Scrubber
Entralnment
wet scrubber
Partlculate
emission rate
grains/s
45.4
14.47
1.73
3.24
45.4
3. 24
45.4
3.24
45.4
3.24
grams/s
2.94
0.94
0.11
0.21
2.94
0.21
2.94
0.21
2.94
0.21
Height of
discharge
feet
193.0
191.0
220.0
60.0
60.0
60.0
60.0
60.0
60.0
60.0
meters
58.83
58.22
67.06
18.29
18.29
18.29
18,29
18.29
18.29
18.29
Stack
diameter
feet
305.0
304.5
4.0
206.0
3.0
3.0
3.0
3.0
3.0
3.0
meters
301.52
301 . 37
1.22
291.83
0.91
0.91
0.91
0.91
0.91
0.91
Stack
temperature
°F
100
100
100
135
135
135
135
115
115
K
310.62.
310.62
310.62
330.04
330.04
330.04
330.04
318.94
318.94
Total
flow
scfm
152,000
122.000
30,000
152,000
20,000
20,000
20,000
20,000
20,000
20,000
Air
rate ,
Std M /mln
4304.64
3455.04
849.60
4304.64
566.40
566.40
566.40
566.40
566.40
566.40
Air velocity
per stack
ft/s
43.0
42.6
39.8
44.8
47.2
47.2
47.2
47.2
47.2
47.2
meters/s
13.11
13.00
12.13
13.66
14.39
14.39
14.39
14.39
14.39
14.39
a20 percent of total airflow goes through collection hood; 80 percent of emission goes through collection hood.
bHetted fibrous filter scrubber.
-------
TABLE 5-8c. EMISSION PARAMETERS: AMMONIUM NITRATE LOW DENSITY
PRILLING PLANT - 816 Mg/Day (900 TONS PER DAY)
01
Emission
Source
Prill Tower
Prill Tower3
Prill Tower
Predryer
Predryer
Dryer
Dryer
Cooler
Cool er
Type of
Discharge
Stack
Stacks
Stacks
Stack
Stack
Stack
Stack
Stack
Stack
Level of
Control
Existing
Option 1
Option 2
Existing
Option 1
Existing
Option 1
Existing
Option 1
Partlculate
Type of emission rate
Control grains/s
Uncontrolled 102.1
Bypass 32.6
Collection 3-90
Hood/WFFSD
1 1 " /. 1-
14" iP HFFSb 7.29
Tray 102.1
Scrubber
Entrainment 7.29
wet scrubber
13"/vP
Tray 102.1
Scrubber
Entrainment 7.29
wet scrubber
Tray 102.1
Scrubber
Entrainment 7.29
wet scrubber
13"AP
grams/s
6.62
2.11
0.25
0.47
6.62
0.47
6.62
0.47
6.62
0.47
Height of
discharge
feet
195.0
195.0
225.0
60.0
80.0
80.0
80.0
80.0
80.0
80.0
meters
59.44
59.44
68.58
18.29
24.38
24.38
24.38
24.38
24.38
24.38
Stack Stack Total Air
diameter temperature flow rate ,
feet
406.0
3P6.0
6.0
406.0
5.0
5.0
5.0
5.0
5.0
5.0
meters °F
401.83 100
301.83 100
1.83
401.03 100
1.52 135
1.52 135
1.52 135
1.52 135
1.52 115
1.52 115
K scfra Std M7m1n
310.62 342,000
310.62 274,000
68,000
310.62 342,000
330.04 45,000
330.04 45,000
330.04 45,000
330.04 45,000
318.94 45,000
318.94 45,000
9,685.44
7,759.68
1,925.76
9,685.44
1,274.40
1,274.40
1,274.40
1,274.40
1,274.40
1,274.40
Air velocity
per stack
ft/s
50.4
53.9
40.1
50.4
38.2
38.2
38.2
38.2
3,2
38.2
meters/s
15.37
16.43
12.22
15.37
11.64
11.64
11.64
11.64
11.64
11.64
a20 percent of total airflow goes through collection device; 80 percent of the emissions goes through collection device.
i_
Wetted fibrous filter scrubber.
-------
operated, should have similar emissions. In addition, there is no other
industry data available to indicate whether another type of control
device would be more applicable or give better performance on granulator
emissions. The discharge parameters for granulation plants are presented
in Tables 5-9a to 5-9c.
5.3.4 Predryers, Dryers and Coolers
For all rotary drum predryers, dryers and coolers, the existing
control is a tray scrubber, as shown in Table 5-6. An entrainment
scrubber with a 3.25 kPa (13 in. W.G.) pressure drop has been selected
as a control option for these facilities. EPA measured particulate
emissions at the inlet and outlet of an entrainment scrubber applied to
the rotary drum cooler of a drum granulation plant. The entrainment
scrubber proved effective in controlling emissions from this source.
EPA also tested a predryer, dryer and cooler at a low density plant and
a cooler at a high density plant. Emissions from all these facilities
were found to be similar in character; therefore, the entrainment scrubber
is considered capable of reducing emissions to the same level when
applied to each of these facilities. For the low density prilling
process, individual control alternatives for predryers, dryers and
coolers will not be considered, since the emissions are similar and all
plants within the industry control all three processes. No case was
identified in the industry where one or two of these processes were
controlled and not the other(s). The discharge parameters for these
facilities are presented, with their respective solid formation facilities,
in Tables 5-7, 5-8 and 5-9.
5.4 CONTROL ALTERNATIVES
This section presents control alternatives applied to ammonium
nitrate solids formation and finishing equipment. These control alternatives
were developed by combining the various control options presented in the
previous section. Control alternatives have been developed for high
density prilling, low density prilling and granulation plants. The
environmental and economic impacts associated with these alternatives
will be evaluated in Chapters 6 and 7.
5-28
-------
TABLE 5-9a. EMISSION PARAMETERS: AMMONIUM NITRATE
GRANULATION PLANT - 363 Mg/Day (400 TONS PER DAY)
Y1
10
Emission Type of
Source Discharge
Granulator Stack
Cooler Stack
Cooler Stack
Level of
Control
Existing
& Option 1
Existing
Option 1
Type of
Control
Entralnment
Scrubber
14"AP
Tray
Scrubber
Entralnnient
Scrubber
13"Ap
Partlculate
emission rate
gralns/s
16.2
45.4
3.24
grams/s
1.05
2.94
0.2l!
Height of
discharge
feet meters
90.0 27.43
60.0 18.29
60.0 18.29
Stack Stack
diameter temperature
feet meters °F K
6.0 1.83 110 316.17
3.0 0.91 115 318.94
3.0 0.91 115 318.94
Total
flow
scfm
40,000
20,000
20,000
Air
rate ,
Std M /mln
1,132.80
566.40
566.40
Air
per
ft/s
23.6
47.2
47.2
velocity
stack
meters/s
7.19
14.39
14.39
-------
TABLE 5-9b. EMISSION PARAMETERS: AMMONIUM NITRATE
GRANULATION PLANT - 726 Mg/Day (800 TONS PER DAY)
en
CO
o
Emission Type of Level of
Source Discharge Control
Gramilator Stack Existing
« Option 1
Cooler Stack Existing
Cooler Stack Option 1
Participate
Type of emission rate
Control gralns/s grams/s
Entralnment
Scrubber 32.4 2.10
14"AP
Tray
Scrubber 90. J 5.88
Entralmnent
Scrubber 6.48 0.4Z
13"AP
Height of
discharge
feet
29
90.0
20
60.0
20
60.0
meters
20
27.43
20
18.29
20
18.29
Stack Stack
Total Air Air velocity
diameter temperature flow rate , per stack
feet
29
6.0
20
3.0
20
3.0
meters °F
20 110
1.83
20 115
0.91
20 115
0.91
K scfw Std M"/m1n ft/s meters/s
316.17 80,000 2,265.60 23.6 7.19
318.94 40,000 1.132.80 47.2 14.39
318.94 40,000 1,132.80 47.2 14.39
-------
tn
ui
TABLE 5-9c. EMISSION PARAMETERS: AMMONIUM NITRATE GRANULATION
PLANT - 1,089 Mg/Day (1,200 TONS PER DAY)
Parttculate
Emission
Source
Granulator
Cooler
Cooler
Type of
Discharge
Stack
ft
Stack
Stack
Level of
Control
Existing
Option 1
Existing
Option 1
Type of
Control
Entrainment
Scrubber
14"AP
Tray
Scrubber
Entrainment
iS AP r
emission rate
gralns/s
48.6
136.1
9.72
grams/s
3.15
8.82
0.63
Height of
discharge
feet
30
9.0.0
30
60.0
30
60.0
meters
30
27.43
30
18.29
30
18.29
Stack
diameter
feet
30
6.0
30
3.0
30
3.0
meters
30
1.83
30
0.91
30
0.91
Stack Total Air
temperature flow rate ,
°F K scfm Std H /mln
110 316.17 120.000 3,398.40
115 318.94 60,000 1,699.20
115 318.94 60,000 1,699.20
Air velocity
per stack
ft/s meters/s
23.6 7.19
47.2 14.39
47.2 14.39
-------
The first control alternative (Alternative No. 1) for each model
plant was chosen to represent the existing level of control (ELOC), as
described in Section 5.2.2. This alternative is used as a basis of
comparison for the other alternatives. The remaining alternatives were
determined by selectively applying more efficient emission control
techniques than the existing control to the facilities in the model
plants. Typically, Alternative No. 2 for each model plant applies more
efficient emission control equipment to the facility with the largest
emissions. Subsequent alternatives are then selected with successively
smaller emissions. This procedure allows an incremental determination
of the impacts associated with applying possible alternatives to individual
facilities within the model plants. Table 5-10 presents combinations of
existing and optional controls applied to the processing facilities for
the various control alternatives.
The existing level of control (ELOC), Alternative No. 1, was presented
in Table 5-6. As discussed in Chapter 4, a variety of emission control
devices are used to control emissions from the various facilities. The
control devices and the emission factors selected for the various
control options are summarized in Table 5-11. The emission control
devices used in the various control alternatives are detailed in Table 5-12
for all the model plants.
5-32
-------
TABLE 5-10. CONTROL ALTERNATIVES FOR AMMONIUM NITRATE PLANTS
Alternative
Number
1 (existing)
2
3
4
4a
Alternative
Number
1 (existing)
2
3
4
Alternative
Number
1 (existing)
2
HIGH DENSITY PRILLING PROCESS
Prill Tower
0
0
X (option 1)
X (option 2)
X (option 3)
LOW DENSITY PRILLING PROCESS
Prill Tower Predryer,
0
0
X (option 1)
X (option 2)
GRANULATION PROCESS
Granulator
0-X*
0-X*
Cooler
0
X
X
X
X
Dryer and Cooler
0
X
X
X
Cooler
0
X
0 - Existing Control
X - Optional Control
*Granulators existing and option control are the same,
5-33
-------
TABLE 5-11. EMISSION FACTORS
Uncontrolled
kg/Hg (Ibs/ton) Exlstlnq Control
Solids Formation
Low Density Prill Towers 0.7 (1.4) None
Illyli Density Prill Towers 1.55 (3.1) Two-Tray Scrubber
2.75 kPa (11" W.G.) AP
en
CO
Granulators 145 (290) Entrapment Scrubber
3.5 kPa (14- W.G.) AP
Solids Finishing
Predryersi Dryer, Cooler 5.4* (10.8)* Tray Scrubber
.75 kPa (3- W.G.) AP
Existing
kg/Hg (Ibs/ton) Control Option Equipment
0.7 (1.4) Option 1
Collection Hood/WFFS*
3.5 kPa (14- W.G.) AP
Option 2
HFFSa
3.5 kPa (14* W.G.) AP
0.7 (1.4) Option I5
Collection Hood/WFFSa
3.5 kPa (14- W.G.) AP
Option 2 and 35
WFFS*
3.5 kPa (14- W.G.) AP
0.25 (0.5) Same
0.7 (1.4) Entrapment Scrubber
3.25 kPa (13" W.G.) AP
Controlled
kg/Hg (Ibs/ton)
0.25
0.05
0.25
0.05
0.25
0.05
(0.5)
(O.I)
(0.5)
(O.I)
(0.5)
(0.1)
*Wetied Fibrous Filter Scrubber
'Average of EPA test data
-------
TABLE 5-12. CONTROL ALTERNATIVES FOR
MODEL AMMONIUM NITRATE PLANTS
Model Plant 1 -
Alternative #
Hl-1
H1-2
Hl-3
HI -4
H1-4a
H2-1 through
H2-4a
H3-1 through
H3-4a
11-1
11-2
L1-3
Ll-4
L2-1 through
L2-4
1.3-1 through
L3-4
G1-1
Gl-2
Gl-1 and
G2-2
G3-1 and
53-2
Process
High Density
Prilling
High Density
Pri 1 1 ing
High Density
Prilling
High .Density
Prill ing
High Density
Prilling
High Density
Prilling
High Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Granulation
Granulation
Granulation
Granulation
Capacity
Mg/Day
(TPD)
363 (400)
363 (400)
363 {400}
363 (400)
363 (400)
726 (800)
1089 (1200)
181 (200)
181 (200)
181 (200)
181 (200)
363 (400)
816 (900)
363 (400)
363 (400)
726 (800)
1089 (1200)
Prill Tower or
Granulator
Tray Scrubber
Tray Scrubber
Collection Hood/WFFS1
(Op.l)
Full Flow UFFSa
(Op.2)
Reduced Flow WFFSa
(Op.3)
Same controls as used
Same controls as used
None
None
Collection Hood/WFFS*
(Op.l)
Full Flow WFFS*
(Op.2)
Same controls as used
Same controls as used
Entraimnent Scrubber
Entrainment Scrubber
Same controls as used
Same controls as used
ca on Ficilfffs;
Predryer, Dryer or
Cooler
Tray Scrubber
Entrainment Scrubber
Entraimnent Scrubber
Entrainment Scrubber
Entrainment Scrubber
on Alternatives Hl-1 through Hl-4a.
on Alternatives Hl-1 through Hl-4a.
Tray Scrubber
Entrainment Scrubber
Entrainment Scrubber
Entrainment Scrubber
on Alternatives Ll-1 through Ll-4.
on Alternatives Ll-1 through Ll-4.
Tray Scrubber
Entrainment Scrubber
on Alternatives G1-1 and Gl-2.
on Alternatives G1-1 and Gl-2.
aVletted Fibrous Filter Scrubber
5-35
-------
5.5 REFERENCES
1. Memo from Anderson, C. D., Radian Corporation, to file. July 2,
1980. 27 p. Tabular summary of information received from the
ammonium nitrate industry.
2. Memo from Bowen, M., Radian Corporation, to file. October 11,
1980. 6 p. Table summarizing source test data obtained under this
study.
3. Search, W. J. and R. B. Reznick (Monsanto Corporation) Source
Assessment: Ammonium Nitrate Production. Prepared for U. S.
Environmental Protection Agency, Research Triangle Park, N. C.
Publication No. EPA-600/2-77-107. September 1977. 78 p.
4. Lowenheim, F. A. and M. K. Mosan, Industrial Chemicals, 4th Edition.
New York, John Liley and Sons, 1975. pp. 97-102.
5. Memo from Apple, C., Radian Corporation, to file. October 22,
1980. 11 p. Support for high density prill tower emission factors,
5-36
-------
6.0 ENVIRONMENTAL IMPACTS
This chapter discusses the environmental impacts associated with
each of the control alternatives for participate emissions in the solid
ammonium nitrate (AN) manufacturing industry. Emission sources to be
considered are low and high density prill towers, granulators and solids
finishing operations (predryers, dryers, coolers). The air pollution,
water pollution, solid waste and energy impacts associated with the
control alternatives are identified and discussed in Sections 6.1 to
6.4, respectively. Other impacts are evaluated in Section 6.5. All
impacts are based on the model plant parameters presented in Chapter 5.
6.1 AIR POLLUTION IMPACT
The impact of each control alternative on air quality is presented
in this section. Two impacts are considered: primary impacts, or the
reduction of particulates due to the application of the control options
and secondary impacts due to pollutants generated as a result of applying
the control equipment.
6.1.1 Primary Air Quality Impacts
Table 6-1 presents total plant emission factors for each model
plant and control alternative outlined in Chapter 5. The reduction in
emissions over the existing level of control (ELOC) due to the application
of the control options, is also presented here. The impacts of the ELOC
(primary emissions, secondary emissions, energy requirements, etc.) are
used as a reference value to compare the impacts of the control alternatives,
The remaining alternatives provide increasing levels of control. These
emission levels are presented on a mass per unit production basis, so
that emission levels for any plant operating under conditions similar to
the model plant can be estimated. The largest reduction in emissions,
2.6 g/kg (5.2 Ib/ton) of AN produced, occurs for Alternative 4 on low
6-1
-------
TABLE 6-1. EMISSION FACTORS AND REDUCTIONS FOR CONTROL ALTERNATIVES
en
i
Model
Plant
Number
H-l-3
L 1-3
G 1-3
Control
Alternative
High Density 1 (ELOC)
I'rllllng 2
3
4
4a
low Density 1 (ELOC)
Irllllnq 2
3
4
(iranulatlon 1 (ELOC)
2
Prill Tower
0
0
X (Option 1)
X (Option 2)
X (Option 3)
Prill Tower
0
n
X (Option 1)
X (Option 2)
Granule tor
n
X
Cooler
0
X
X
X
X
Predryer, dryer
and cooler
0
X
X
X
Cooler
0
X
Emission Factor3 Reduction beyond ELOC
g/kg Ib/ton g/kg Ib/ton percent
1.40 (2
0.75 1
0.30 0
0.10 iO
0.10 (0
2.80 5
0.85 1
0.40 0
0.20 0
0.95 (1
0.30 (0
.80)
.50 0
60 1
20 1
.20 1
60)
.70 1
80) 2
40) 2
.90)
60) 0
« •
.65 (1.30
.10 (2.20
.30 (2.60
0
46
79
93
.30 (2.60) 93
m —
.95 (3. 90]
.40 (4.80
0
70
86
.60) (5.20) 93
^ —
0
.65 (1.30) 68
Emission factors reflect total emissions, Including bypass emissions when applicable.
This option Is for a reduced flow wetted fibrous filter scrubber, no reduction In emissions are credited.
Impacts will be changed.
0 - Existing Level of Control
X - Optional Control
However, environmental
-------
density plants. This is a 93 percent reduction beyond ELOC. Table 6-2
presents the total annual particulate reduction over existing control
levels for each model plant and control alternative. Emission reductions
range from 76 Mg/year (84 TRY) for Alternative 2 for Model Plant H-l to
683 Mg/year (753 TRY) for Alternative 4 for Model Plant L-3.
6.1.2 Secondary Air Quality Impacts
Secondary air pollutants are generated as a result of applying the
control equipment. For ammonium nitrate plants, no air pollutants are
generated by the control equipment used to achieve various control
levels. There is, however, an increase in offsite power plant emissions
caused by the additional electrical demand of the control equipment and
the steam demand required to utilize the recovered AN particulates from
scrubber liquor. For illustration, it was assumed that both the electrical
and steam energy demand would be met by a coal fired utility boiler.
These energy requirements are discussed in Section 6.4. Pollutants
associated with the power plant would be particulates, SCL and NO .
Table 6-3 presents the range of secondary air emissions for each
type of model plant. These are presented as the expected increase in a
coal burning power plant's emissions over power plant emissions based on
the control equipment used to meet the existing levels of control.
Furthermore, the emissions for the power plant would meet current New
Source Performance Standards. For the least affected case, Alternative
3 for Model Plant H-l, a decrease in power plant particulate emissions
of 0.008 g/kg (0.016 Ib/ton) of AN produced would occur, because this
alternative requires less energy than the existing control levels. In
the worst case, Alternative 4 for Model Plant L-l, power plant emissions
would increase by 0.036 g/kg (0.072 Ib/ton) of AN produced. The corresponding
reduction in the low density plant's AN particulate emissions over ELOC
from applying the alternative would be 2.6 g/kg (5.2 Ib/ton) of AN
produced. Therefore, the increase in power plant particulate emissions
would be less than 1.4 percent of the reduction in emissions caused by
Alternative 4.
6-3
-------
TABLE 6-2. TOTAL ANNUAL REDUCTION OVER EXISTING LEVEL OF CONTROL OF
PARTICULATE EMISSIONS FOR CONTROL ALTERNATIVES
Mg/Year (Tons/Year)
en
i
Model Plant
Number
H-1
H-2
H-3
L-1
I.-2
L-3
G-1
G-2
G-3
Model Plant Capacity
Plant Kg/Day (TPD)
High Density 363
Prilling
726
1089
Low Density 181
Prilling
363
816
Granulator 363
726
1089
(400)
(800)
(1200)
(200)
(400)
(900)
(400)
(800)
(1200)
Control Alternative
1234
76 (84)
152 (167)
228 (251)
114 (1E6)
228 (251)
512 (565)
76 (84)
152 (167)
228 (251)
129 (142)
258 (284)
387 (426)
140 (155)
281 (309)
631 (696)
152 (167)
305 (335)
456 (502)
152 (167)
304 (335)
683 (753)
4a
152 (167)
305 (335)
456 (502)
-------
TABLE 6-3. SECONDARY AIR IMPACTS OVER ELOC FOR,EACH
MODEL PLANT AND CONTROL ALTERNATIVE1
en
en
Control
Model Plant Alternative
H-1 2
3a
Ji
H-2 2,
3a
,'i
H-3 2
3a
it
L-1 2
3
4
L-2 2
3
4
L-3 2
3
4
G-l 2
G-2 2
G-3 2
Power Plant
Participate Emissions
,, Over ELOC ,,
10"* g/kg 10"' Ih/ton
0.45
-0.80
1.11
-0.65
0.33
-0.68
1.14
-0.49
0.39
-0.67
1.20
-0.50
1.07
1.68
3.59
1.06
1.66
3.57
1.06
1.70
3.50
0.35
0.35
0.35
0.91
-1.60
2.22
-1.30
0.67
-1.36
2.29
-0.98
0.78
-1.34
2.40
-1.00
2.15
3.37
7.18
2.12
3.33
7.14
2.13
3.41
7.01
0.70
0.70
0.70
AN Particulate
Emissions Reduction
From ELOC
g/kg Ib/ton
0.65
1.1
1.3
1.3
0.65
1.1
1.3
1.3
0.65
1.1
1.3
1.3
1.95
2.4
2.6
1.95
2.4
2.6
1.95
2.4
2.6
0.65
0.65
0.65
1.3
2.2
2.6
2.6
1.3
2.2
2.6
2.6
1.3
2.2
2.6
2.6
3.9
4.8
5.2
3.9
4.8
5.2
3.9
4.8
5.2
1.3
1.3
1.3
Percent Impact of
Secondary Emissions Power Plant S02
Over AN Emissions Emissions Over ELOC
Reduction g/kg Ib/ton
0.7
-0.7
0.8
-0.5
0.5
-0.6
0.9
-0.4
0.6
-0.6
0.9
-0.4
0.5
0.7
1.4
0.5
0.7
1.4
0.5
0.7
1.3
0.5
0.5
0.5
0.02
-0.03
0.05
-0.03
0.01
-0.03
0.05
-0.02
0.01
-0.03
0.05
-0.02
0.04
0.07
0.15
0.04
0.07
0.15
0.04
0.07
0.15
0.01
0.01
0.01
0.04
-0.07
0.10
-0.06
0.03
-0.06
0.10
-0.04
0.03
-0.06
0.10
-0.04
0.09
0.15
0.31
0.09
0.14
0.31
0.09
0.15
0.31
0.03
0.03
0.03
Power Plant NO-
Emissions Over ElOC
g/kg Ib/ton
0.02
-0.03
0.04
-0.02
0.01
-0.03
0.04
-0.02
0.01
-0.03
0.05
-0.02
0.04
0.07
0.14
0.04
0.07
0.14
0.04
0.07
0.14
0.01
0.01
0.01
0.04
-0.07
0.09
-0.05
0.03
-0.06
0.09
-0.04
0.03
-0.06
0.10
-0.04
0.09
0.14
0.29
0.09
0.14
0.29
0.09
0.14
0.29
0.03
0.03
0.03
aThe power plant emissions (secondary emissions) are less than the ELOC for this alternative because the control equipment for this
alternative requires less energy than the control equipment for the ELOC.
-------
Table 6-3 also presents the increases in S02 and NOX power plant
emissions for each type of model plant. Alternative 4 for Model Plant L-l
causes the largest increase in these emissions. In this case, the power
plant would generate an increase in SCL and NO emissions of 0.150 g/kg
£ /\
(0.313 Ib/ton) and 0.145 g/kg (0.291 Ib/ton) of AN produced, respectively.
The assumptions and calculations used in developing these air quality
impacts can be found in Reference 1.
6.1.3 Summary of Air Quality Impacts
The primary air pollutant emissions from affected facilities in the
AN industry are AN particulates. The major benefit of implementing the
control alternatives is a reduction of particulate emissions, and thus a
potential lessening of health and environmental hazards. The largest
reduction in AN particulate emissions which would result from applying
the control alternatives would be 683 Mg/year (753 TRY) for Alternative 4
of Model Plant L-3. The corresponding increase in power plant emissions
would be 9.20 Mg/year (10.14 TPY), which is only a 1.3 percent impact on
the particulate emission reduction. Therefore, the potential secondary
air emissions are not considered significant.
6.2 WATER POLLUTION IMPACT
There would be no adverse water pollution impact due to the imple-
mentation of the proposed control alternatives. Water used in the wet
scrubbers to control particulate emissions is usually recycled to the
solution concentration process for complete recovery of the ammonium
nitrate.
6.3 SOLID WASTE IMPACT
There would be no solid waste impact due to the application of the
control alternatives, since the collected AN emissions are dissolved in
the scrubber liquor and recycled to solution formation.
6.4 ENERGY IMPACT
The energy impact of the control alternatives is less than seven
percent of the energy needed for the process equipment. The process
equipment energy includes energy needs from solution formation through
the finishing of the final product.2
6-6
-------
The control of emissions involves the use of both electricity and
steam. Electricity is used to power the pumps and fans associated with
the control devices while steam is required to concentrate the weak
scrubber liquor when it is recycled to the process.
The energy requirements for each model plant and control alternative
are presented in Table 6-4. The incremental energy consumption over the
energy required to meet existing level of control (ELOC) in addition to
its percentage of the total plant energy demand is shown for each
alternative. In the cases where a negative energy requirement over ELOC
occurs, the control alternative requires less energy for operation than the
control equipment used to meet the ELOC. Energy requirements over ELOC
for the control equipment range from -11.72 TJ/yr (-11.11 x 10 Btu/yr)
to 46.04 TJ/yr (43.64 x 109 Btu/yr). The effect on total plant energy
demand associated with the control alternatives over ELOC ranges from -
0.8 percent for Alternative 3 for Model Plant H-l to 3.7 percent for
Alternative 4 for Model Plant L-l.
6.5 OTHER IMPACTS
There would be no significant noise impact due to implementation of
the regulatory alternatives. The increase in noise caused by the
addition of fans for the control equipment would be small compared to
the noise already generated by process equipment.
6-7
-------
TABLE 6-4. ENERGY REQUIREMENT FOR MODEL PLANTS
AND CONTROL ALTERNATIVES
CTl
I
CO
Model
Plant
H-1
H-2
H-3
L-1
1-2
1-3
G-1b
G-2b
G-3b
Control
Alternative
1
2
3
4
4a
1
2
3
4
4a
1
2
3
4
4a
1
2
3
4
1
2
3
4
1
2
3
4
1
2
1
2
1
2
Control Equipment Energy
10* Btu/yr
16.66
19.18
12.21
22.80
13.08
32.22
35.94
24.69
44.90
26.76
47.20
53.68
36.09
67.11
38.88
7.30
10.28
11.96
17.22
14.50
20.37
23.71
34.26
32.69
45.93
53.92
76.33
4.73
6.68
9.46
13.35
14.19
20.03
TJ/yr
17.58
20.23
12.88
24.05
13.80
33.99
37.92
26.05
47.37
28.23
49.80
56.63
38.07
70.80
41.02
7.70
10.85
12.62
18.17
15.30
21.50
25.01
36.14
34.48
48.45
56.89
80.52
4.99
7.05
9.98
14.08
14.97
21.13
Energy Requirements
Over ELOC
10» Btu/yr
.
2.52
-4.45
6.14
-3.58
_
3.72
-7.53
12.68
-5.46
.
6.48
-11.11
19.91
-8.32
_
2.98
4.66
9.92
_
5.87
9.21
19.76
_
13.24
21.24
43.64
_
1.95
_
3.89
—
5.84
TJ/yr
.
2.66
-4.69
6.48
-3.78
_
3.93
-7.94
13.38
-5.76
_
6.83
-11.72
21.00
-8.78
_
3.14
4.91
10.46
_
6.20
9.71
20.85
.
13.97
22.41
46.04
_
2.06
—
4.10
—
6.16
Total Plant
10^ Btu/yr
544
544
544
544
544
1086
1086
1086
1086
1086
1630
1630
1630
1630
1630
271
271
271
271
544
544
544
544
1223
1223
1223
1223
578
578
1153
1153
1731
1731
Energy3
TJ/yr
574
574
574
574
574
1146
1146
1146
1146
1146
1720
1720
1720
1720
1720
286
286
286
286
574
574
574
574
1290
1290
1290
1290
610
610
1216
1216
1826
1826
Energy Requirement Over
ELOC as Percent of
Total Plant Energy
.
0.5
-0.8
1.1
-0.7
..
0.3
-0.7
1.2
-0.5
.
0.4
-0.7
1.2
-0.5
_
1.1
1.7
3.7
„
1.1
1.7
3.6
.
1.1
1.7
3.6
_
0.3
_
0.3
_
0.3
alncludes energy needed for solution formation through finishing of the final product.
The control equipment for the granulator 1s considered In the plant energy requirements, not 1n the
control equipment energy requirements.
-------
6.6 REFERENCES
1. Memo from Bowen, M. L., Radian Corporation, to file. September 1980.
4 p. Summary of secondary air pollution impact calculations.
2. Faith, W. L., Keyes and Clark. Industrial Chemicals. New York,
John Wiley and Sons. 1975. 97-99.
6-9
-------
7.0 COST ANALYSIS
A cost analysis of the control alternatives described in Chapter 5
is presented in this chapter. This chapter is divided into two major
sections. Section 7.1 presents the costs associated with various
control alternatives, including an analysis of capital and annualized
costs. Both new facilities and existing facilities are considered.
Other costs that may result from the application of control equipment
are considered in Section 7.2, including costs imposed by water pollution
control regulations and solid waste disposal requirements.
7.1 COST ANALYSIS OF CONTROL ALTERNATIVES
7.1.1 Introduction
The costs of implementing the control alternatives to control
emissions from the solid ammonium nitrate industry are presented in this
section. The cost analysis is based upon the model ammonium nitrate
plants and the control alternatives presented in Chapter 5. The nine
model plants, and the sources being controlled, are shown in Table 7-1.
Emission factors for each source are presented in Table 7-2, and the
control alternatives for each plant are presented in Table 7-3.
The cost of purchasing, installing and operating various control
devices are presented in the following sections. The purchase costs for
1 2
the control equipment (wetted fibrous filter scrubbers , entrainment
scrubbers , two-tray scrubbers ' , and tray scrubbers ) were obtained
from vendor quotes. Cost estimating manuals and published reports were
78 9
used to determine costs for auxiliary equipment, (fans , pumps , motors ,
starters , downcomers , and stacks ). Equipment costs were scaled up
to first quarter 1980 dollars using the Marshall and Stevens1 index for
the chemicals industry.
Total capital cost for installation of the various control devices
was determined by applying component factors to the basic equipment
7-1
-------
TABLE 7-1. MODEL AMMONIUM NITRATE PLANTS FOR COST ESTIMATES
ro
Model
Plant 4
H-l
H-2
H-3
L-l
L-2
L-3
G-1
G-2
6-3
! Process
High Density Prilling
High Density Prilling
High Density Prilling
Low Density Prilling
Low Density Prilling
Low Density Prilling
Granulation
Granulation
Granulation
Capacity
Mg/Day (TPD)
363 (400)
726 (800)
1089 (1200)
181 (200)
363 (400)
816 (900)
363 (400)
726 (800)
1089 (1200)
Emission Sources
Prill Tower, Rotary Drum Cooler
Prill Tower, Rotary Drum Cooler
Prill Tower, Rotary Drum Cooler
Prill Tower; Rotary Drum Predryer, Dryer, and Cooler
Prill Tower, Rotary Drum Predryer, Dryer, and Cooler
Prill Tower; Rotary Drum Predryer, Dryer, and Cooler
Rotary Drum Granulator, Rotary Drum Cooler
Rotary Drum Granulator, Rotary Drum Cooler
Rotary Drum Granulator, Rotary Drum Cooler
-------
TABLE 7-2. EMISSION FACTORS
Uncontrolled
kg/Mg (Ibs/ton) Exlstlnq Control
Solids formation
Low Density Prill Towers 0.7 (1.4) None
High Density Prill Towers 1.55 (3.1) Two-Tray Scrubber
2.75 kPa (11" W.G.) AP
1
CO
Granulators 145 (290) Entralnment Scrubber
3.5 kPa (14" W.G.) AP
Solids Finishing
Predryers, Dryer, Cooler 5.4* (10.8)* Tray Scrubber
.75 kPa (3" W.G.) AP
Exlsttnq
kg/Mg (Ibs/ton) Control Option Equipment
0.7 (1.4) Option 1
Collection Mood/WFFS*
3.5 kPa (14" W.G.) AP
Option 2
WFFS
3.5 kPa (14" W.G.) AP
0.7 (1.4) Option I5
Collection Hood/WFFSa
3.5 kPa (14" W.G.) AP
Option 2 and 35
WFFS3
3.5 kPa (14" U.G.) AP
0.25 (0.5) Same
0.7 (1.4) Entralnment Scrubber
3.25 kPa (13* W.G.) AP
Controlled
kg/Mg (Ibs/ton)
0.25
0.05
0.25
0.05
0.25
0.05
(0.5)
(0.1)
(0.5)
(0.1)
(0.5)
(0.1)
"Wetted Fibrous Filter Scrubber
•Average of EPA test data
-------
TABLE 7-3. CONTROL ALTERNATIVES FOR MODEL AMMONIUM NITRATE PLANTS
Model Plant * -
Alternative 1
Hl-1
Hl-2
Hl-3
HI -4
H1-4a
H2-1 through
H2-4a
H3-1 through
H3-4a
Ll-1
LI- 2
Ll-3
Ll-4
L2-1 through
L2-4
L3-1 through
1.3-4
E1-1
Gl-2
Gl-1 and
S2-2
G3-1 and
G3-2
Process
High Density
Prilling
High Density
Prill las
High Density
PHlltng
High Density
Prilling
High Density
Prilling
High density
Prilling
High Density
Prilling
Low [tensity
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Low Density
Prilling
Granulation
Granulation
Granulation
Granulation
Capacity
Mg/Day
(TPD)
363 (400)
363 (400)
363 (400)
363 (400)
363 (400)
726 (800)
1089 (1200)
181 (200)
181 (200)
181 (200)
181 (200)
363 (400)
816 (900)
363 (400)
363 (400)
726 (800)
1089 (1200)
Type of Control Device on Facilities
Prill Tower or
Sranulator
Tray Scrubber
Tray Scrubber
Collection Hood/WFFS*
(Op.l)
Full How MFFS*
(Op.2)
deduced Flow WFFSa
(Op.3)
Sane controls as used
Sane controls as used
None
None
Collection Hood/WFFS*
(Op.l)
Full How WFFS*
(Op.2)
Same controls as used
Sane controls as used
Entralnment Scrubber
Entrainment Scrubber
Sane controls as used
Same controls as used
Predryer, Dryer or
Cooler
Tray Scrubber
Entralnment Scrubber
Entrainment Scrubber
Entrainment Scrubber
Entrainment Scrubber
on Alternatives Hl-1 through Hl-4a.
on Alternatives Hl-1 through Hl-4a.
Tray Scrubber
Entralnment Scrubber
Entralnment Scrubber
Entrainoent Scrubber
on Alternatives Ll-1 through Ll-4.
on Alternatives Ll-1 through Ll-4.
Tray Scrubber
Entrainment Scrubber
on Alternatives Gl-1 and Gl-2.
on Alternatives Gl-1 and Gl-2.
aUetted Fibrous Filter Scrubber
7-4
-------
costs. These component factors, obtained from a cost estimating manual,
take into account direct costs (ductwork, piping, electrical, instrumen-
tation, structural costs, construction labor, etc.). indirect costs
1"?
(engineering, contractor's fee, taxes, etc.), and contingencies.
The annual cost of operating and maintaining the control devices
includes direct operating expenses (utilities, labor , maintenance )
and capital charges. Capital charges include insurance , administrative
overhead , taxes , and capital recovery (the annual cost for the
payoff of the control devices).'5 Any net savings obtained from the
application of the control equipment is subtracted from the annual
operating costs to obtain the net annual cost of the control alternatives.
Net savings is obtained from the ammonium nitrate recovered by the
control equipment.
The net annual cost is divided by the quantity of pollutant removed
by the control alternatives to determine the cost effectiveness of the
control alternatives. Cost effectiveness is used as a means of comparing
various alternatives.
The costs associated with controlling emissions from new facilities
are discussed in Section 7.1.2. Cost considerations for existing facilities
are discussed in Section 7.1.3.
7.1.2 New Facilities
Capital and annualized costs of applying the control alternatives
to new ammonium nitrate solids production and finishing facilities are
presented in this section. The costs associated with the control alternatives
are presented in six subsections. Section 7.1.2.1 presents important
considerations used in the determination of control equipment costs.
Section 7.1.2.2 discusses the capital costs, and Section 7.1.2.3
presents the annual costs of the control alternatives. The effect of
the control alternatives on ammonium nitrate product cost is described
in Section 7.1.2.4. Section 7.1.2.5, cost effectiveness, compares the
annual costs of the control options to existing cases. The base cost of
an ammonium nitrate plant is discussed in Section 7.1.2.6.
7-5
-------
A 363 Mg/day (400 TPD) plant is used to compare equipment requirements
and costs, because all three types of plants have a model plant of this
size.
7.1.2.1 Basis for Equipment Costs. This section presents important
points which were considered in determining the costs of the control
equipment. All the equipment, except for motors and starters, is made
of stainless steel because of the corrosiveness of ammonium nitrate.
Table 7-4 presents control equipment operating parameters which were
obtained from vendors and are typical of industrial operation. The
control devices and auxiliary equipment were sized to handle the airflows
and emissions specified for the model plants in Tables 5-7 through 5-9.
An example of the equipment needed to control emissions from the sources
in 363 Mg/day (400 TPD) model plants are presented in Tables 7-5a through
7-5d. Figures 7-1 and 7-2 are included to clarify the location of the
control equipment, stacks, fans and ductwork for the prilling towers.
These figures are representative and do not show exact placement of the
equipment.
Wet scrubbers are used to control emissions from both solids formation
facilities, granulators and prill towers, and from solids finishing
facilities, predryers, dryers and coolers. The purchase cost of the
I O
control equipment includes the cost of a scrubber (wetted fibrous filter ',
entrapment3, two-tray4'5, tray6), fan7, recirculating pump8, the associated
9 9 10 11
motors and starters , downcomers and stacks.
State regulations require that new plants must be testable, which
means a stack on the discharge. Therefore, even in cases where no
control is required, like the low density prill tower, fan and stack
costs were determined.
Various techniques are used for applying the selected control
equipment to the different sized model prilling and granulation plants.
For prilling operations and their solids finishing equipment, the facilities
are sized for a capacity equivalent to the overall plant production
capacity. Granulation facilities, on the other hand, are usually one
specific size. Production capacity for the granulation plant is met
7-6
-------
TABLE 7-4. CONTROL EQUIPMENT SPECIFICATIONS
Two-Tray Scrubber (for prill towers)
Pressure Drop: 2.75 kPa (TLin H20)5 .
Liquid to Gas Ratio: 0.47 m liq./lOOO acm gas (3.5 gpm/1000 acfm)
Construction Material: 316 SS
Fan Location: At scrubber exhaust
Scrubber liquor is returned to process
Tray Scrubber (for predryers, dryers, and coolers)
Pressure Drop: .75 kPa (3.0 in H20)6 fi
Liquid to Gas Ratio: 0.4 nr liq.71000 acm gas (3 gpm/1000 acfm)
Construction Material: 304 SS
Fan Location: At scrubber exhaust
Scrubber Liquor is returned to process
Inlet Velocity: 15.2 m/s (3000 fpmr
Entrainment Scrubber (for predryers, dryers, coolers, granulators)
Pressure Drop: 3.2 kPa (13,in hLO)3, 3.5 kPa (14 in H?0) for granulators
Liquid to Gas Ratio: .87 nr liqf/1000 acm gas (6.5 gpm/1000 acfm)
Construction Material: 304 SS
Fan Location: At scrubber exhaust
Scrubber Liquor is returned to process
Wetted Fibrous Filter Scrubber (for prill towers)
Pressure Drop: 3.5 kPa (14.0 in H20)2
Liquid to Gas Ratio: .47 m3 liq./TOOO acm gas (3.5 gpm/1000 acfm)
Air Velocity: .13 m/s (25 ft/min) through high energy elements
Wetted fibrous filter scrubber used in conjunction with a dust collection
hood controls 20 percent of total tower airflow
Construction Material: Glass fiber filter elements, 304 SS for
shell and dust collection hood
Fan Location: At scrubber exhaust
Scrubber liquor is returned to process
7-7
-------
TABLE 7-5a. MAJOR EQUIPMENT REQUIREMENTS FOR CONTROL OF HIGH DENSITY
PRILL TOWERS 363 Mg/Day (400 TPD) FACILITY
I. EXISTING LEVEL OF CONTROL
Control Device
Fans and Motors
Stacks
Recirculation Pump and Motor
Two-Tray Scrubber, Airflow through device:
83 acms (176,000 acfm)
3 @ 24 scms (51,700 scfm) 9 311 K (100°F),
1200 rpm, 104 kw (140 bhp)
3 @ 1.5 m (5 ft.) diameter, 7 m (23 ft.)
high, SS
2.4 m3/min (620 GPM) 299 kPa (100 ft.
of water) 30 kw (40 bhp)
II. CONTROL OPTION I
Control Device
Fan and Motor
Stack
Recirculation Pump and Motor
Bypass Fans
Bypass Stacks
Collection Hood/Wetted Fibrous Filter
Scrubber, Airflow through device:
17 acms (35,200 acfm)
15 scms (31,000 scfm) @ 311 K (100°F),
1800 rpm, 75 kw (100 bhp)
1.2 m (4.0 ft.) diameter, 12 m (40 ft.)
high, SS-stack from scrubber
.47 m3/min (125 GPM), 299 kPa (100 ft.
of water) 6.0 kw (8 bhp)
3 @ 20 scms (41,300 scfm) @ 311 K (100°F),
600 rpm, 3.7 kw (5 bhp)
3 @ 1.4 m (4.5 ft.) diameter, 9.5 m
(31 ft.) high,SS
7-8
-------
TABLE 7-5a (cont.)
MAJOR EQUIPMENT REQUIREMENTS FOR CONTROL OF HIGH DENSITY PRILL TOWERS
III. CONTROL OPTION 2
Control Device
Downcomer
Fans and Motors
Stacks
Recirculation Pump and Motor
Wetted Fibrous Filter Scrubber, Airflow
through device: 83 acms (176,000 acfm)
304 SS ductwork, 2.7 m (9 ft.)
diameter, 76 m (250 ft.) length
2
-------
I. EXISTING - TWO-TRAY SCRUBBER
II. OPTION 1 - COLLECTION HOOD/WETTED
FIBROUS FILTER SCRUBBER (WFFS)
FANS
SPRAY-
- TWO-TRAY
SCRUBBER
DUCTING
STACKS
CONVEYING
•DUCTING
WFFS
FANS
COLLECTION
HOOD
STACKS
DUCTING
SPRAY
III. OPTION 2-FULL FLOW WETTED
FIBROUS FILTER SCRUBBER (WFFS)
SPRAY-
CONVEYING L_
• DOWNCOMER
-STACKS
r-DUCTING >
WFFS
FANS
IV. OPTION 3 - REDUCED FLOW WETTED
FIBROUS SCRUBBER (WFFS)
-STACK
WFFS
FAN
SPRAY-
CONVEYING
•DUCTING
Figure 7-1.
Control equipment configuration for high density
prill towers - 363 Mg/day (400 TPD).
7-10
-------
TABLE 7-5b. MAJOR EQUIPMENT REQUIREMENTS FOR CONTROL OF LOW DENSITY
PRILL TOWERS 363 Mg/Day (400 TPD) FACILITY
I. EXISTING LEVEL OF CONTROL
Fans and Motors
Stacks
3 @ 24 scms (50,700 scfm) @ 311 K
(100°F) 600 rpm, 4.5 kw (6 bhp)
3 @ 1.5 m (5 ft.) diameter, 10 m
(33 ft.) high
II. CONTROL OPTION I
Control Device
Fan and Motor
Stack
Recirculation Pump and Motor
Bypass Fans
Bypass Stacks
Collection Hood/Wetted Fibrous Filter
Scrubber, Airflow through device:
16.5 acms (34,900 acfm)
14 scms (30,000 scfm) @ 311 K (100°F),
1800 rpm, 75 kw (100 bhp)
1.2 m (4.0 ft.) diameter, 12 m (40 ft.)
high, SS-stack from scrubber
.47 m3min (125 gpm), 299 kPa (100 ft.
of water), 6.0 kw (8 bhp)
3 @ 19 scms (40,700 scfm) @ 311 K (100°F),
600 rpm, 3.7 kw (5 bhp)
3 @ 1.4 m (4.5 ft.) diameter, 9.5 m
(31 ft.) high, SS
III. CONTROL OPTION 2
Control Device
Downcomer
Wetted Fibrous Filter Scrubber, Airflow
through device: 82 acms (173,000 acfm)
304 SS ductwork, 2.7 m (9 ft.) diameter,
76 m (250 ft.) length
7-11
-------
TABLE 7-5b (cont.)
MAJOR EQUIPMENT REQUIREMENTS FOR CONTROL OF LOW DENSITY PRILL TOWERS
Fans and Motors
Stacks
Recirculation Pump and Motor
2 (3 36 sons (76,000 scfm) @ 311 K (100°F),
1200 rpm, 205 kw (275 bhp)
2 I? 1.8 m (6 ft.) diameter, 18 m (60 ft.)
high, SS
2.4 m3/min (620 gpm), 299 kPa (100 ft. of
water), 30 kw (40 bhp)
7-12
-------
I. EXISTING - UNCONTROLLED
II. OPTION 1 - COLLECTION HOOD/WETTED
FIBROUS FILTER SCRUBBER (WFFS)
STACKS
FANS
SPRAY-
CONVEYING
WFFS
FANS—^
DUCTING
SPRAY
STACKS
DUCTING
\_COLLECT1ON
HOOD
III. OPTION 2 - FULL FLOW WETTED
FIBROUS FILTER SCRUBBER (WFFS)
DOWNCOMER
SPRAY
WFFS
FANS
Figure 7-2. Control equipment configuration for low density
prill towers - 363 Mg/day (400 TPD).
7-13
-------
TABLE 7-5c. MAJOR EQUIPMENT REQUIREMENTS FOR CONTROL OF
GRANULATORS 363 Mg/Day (400 TPD) FACILITY
Control Device
Fan and Motor
Stack
Recirculation Pump and Motor
Entrainment Scrubber, Airflow through
device: 22 acms (47,500 acfm)
18.9 sens (40,000 SCFM) @ 316 K (110°F),
1800 rpm, 112 kw (150 bhp)
1.8 m (6 ft.) diameter, 18 m (60 ft.)
high, SS
1.2 m3/min (310 gpm), 299 kPa (100 ft. of
water), 15 kw (20 bhp)
7-14
-------
TABLE 7-5d. MAJOR EQUIPMENT REQUIREMENTS FOR CONTROL OF COOLERS,
DRYERS, PREDRYERS 363 Mg/Day (400 TPD) FACILITY
I. EXISTING LEVEL OF CONTROL
Control Device
Fan and Motor
Stack
Recirculation Pump and Motor
Tray Scrubber, Airflow through
device: 11 acms (24,000 acfm)
9.4 sons (20,000 scfm) @ 330 K (135°F),
900 rpm, 15 kw (20 bhp)
.91 (3.0 ft.) diameter, 9 m (30 ft.)
high, SS
.28 m3/min (75 6PM), 299 kPa (100 ft. of
water), 3.7 kw (5 bhp)
II. OPTION CONTROL
Control Device
Fan and Motor
Stack
Recirculation Pump and Motor
Entrainment Scrubber, Airflow through
device: 11 acms (24,000 acfm)
9.4 sons (20,000 scfm) @ 330 K (135°F)
1800 rpm, 60 kw (80 bhp)
.91 m (3.0 ft.) diameter, 9 m (30 ft.)
high, SS
.60 m3/min (160 GPM), 299 kPa (100 ft. of
water), 6.7 kw (9 bhp)
7-15
-------
by constructing multiple processing trains to reach the desired capacity.
As discussed in Chapter 5, the model granulation plant has a capacity of
363 Mg/Day (400 TPD). To meet the other model plant capacities, 726
Mg/Day (800 TPD) and 1089 Mg/Day (1200 TPD), two and three 363 Mg/Day
(400 TPD) processing trains were used.
Control equipment for prilling plants and their solids finishing
equipment was sized for specific airflows associated with the model
plants. For the granulation plant, the control equipment was sized for
airflows from the 363 Mg/Day (400 TPD) plant. For the other granulation
plants, the control equipment was the same size and was added to the
additional processing train. The equipment cost, therefore, was obtained
by doubling or tripling the costs of the 363 Mg/Day (400 TPD) control
equipment.
In addition, the prill tower control equipment location was varied
depending on the control option used. For the full airflow case (Option
2 in both model plants), the wetted fibrous filter scrubber was too
large to place on the top of the tower. Therefore, for Option 2 a
downcomer was required to collect and discharge prill tower emissions to
a ground level wetted fibrous filter scrubber. For all other options
the control equipment was located on top of the tower, and the additional
cost of constructing a prill tower capable of supporting the control
equipment was estimated. These costs and procedures would not apply to
existing prill towers.
7.1.2.2 Capital Costs. Capital costs represent the total investment
required for purchase and installation of the basic control equipment
and associated auxiliaries. Capital cost estimates for each control
system were developed by applying cost component factors to the equipment
costs to obtain total capital costs (including indirect costs). Costs
for research and development, and costs for possible production losses
during equipment installation and start-up are not included. Costs are
presented in first quarter 1980 dollars.
7-16
-------
Total cost for the complete purchase and installation of the
control equipment and auxiliaries was determined by applying the component
factors outlined in Table 7-6 to the basic equipment costs. As an
example, the capital costs associated with controlling emissions from
individual sources (i.e. cooler, dryer, predryer, prill tower, and
granulator) in the 363 Mg/day (400 TPD) model ammonium nitrate plants
are presented in Table 7-7. This table provides the cost of the control
devices alone, the costs for all major equipment, and the total installed
capital costs to control the emission sources.
The costs of the control equipment needed for each individual
source were combined (Table 7-3) to give the total installed cost and
total equipment cost for each control alternative. The capital costs of
the control alternatives are presented in Table 7-8. Included in Table
7-8 are total equipment cost, including auxiliaries, total installed
capital cost of the equipment, and a comparison of total installed cost
for the alternatives relative to the existing level of control (Alternative 1).
Also included in Table 7-8 are the emissions reductions achieved by the
various control alternatives. This information is used to determine the
recovery credit of the control alternatives.
Since the cost of scrubber systems is directly related to the
airflow through the scrubber, some of the control options have lower or
slightly higher capital costs than the ELOC. Alternative 4a for high
density prill towers uses a reduced airflow; therefore, the control
equipment costs less than the ELOC. In the case of Alternative 3 for
both types of prilling operations, the scrubber only treats twenty
percent of the airflow and the control equipment cost is only six percent
greater than the costs of the ELOC. Presently, some plants in the AN
industry use these control systems to control prill tower emissions.
7.1.2.3 Annualized Costs. Annualized costs represent the yearly
cost of operating and maintaining the pollution control system. The
basis for the annualized cost estimates is presented in Table 7-9. All
annualized costs were based on 7728 hr/yr of operation.
7-17
-------
TABLE 7-6.
COMPONENT CAPITAL COST FACTORS14 FOR WET SCRUBBERS
AS A FUNCTION OF EQUIPMENT COST, Q
Conjoonent
Equipment
Ductwork
Instrumentation
Electrical
Foundations
Structural
Sitework
Painting
Piping
Total direct costs
Direct costs
Material
1.00 Q
0.08 Q
0.05 Q
0.06 Q
0.03 Q
0.06 Q
0.02 Q
0.005 Q
0.09 Q
1.40 Q
Labor
0.09 Q
0.07 Q
0.02 Q
0.12 Q
0.05 Q
0-.03 Q
0.02 Q
0.02 Q
0.08 Q
0.50 Q
Component
Engineering
Contractor's fee
Shakedown
Spares
Freight
Taxes
Indirect costs
Measure of costs
10 percent material and labor
15 percent material and labor
5 percent material- and labor
1 percent material
3 percent material
3 percent material
Total indirect costs
Contingencies - 20 percent of direct and indirect costs
Total capital costs
Factor
0.19 Q
0.29 Q
0.10 Q
0.01 Q
0.04 Q
0.04 Q
0.67 Q
0.51 Q
3.08 Q
7-18
-------
TABLE 7-7. CAPITAL COST FOR THE CONTROL OF INDIVIDUAL SOURCES
IN 363 Mg/Day (400 TPD) MODEL AMMONIUM NITRATE PLANTS
Plant Type
High Density
Prilling
Low Density
Prilling
Sranul ation
Source of
Emissions
Cooler
Cooler
Prill Tower
Prill Tower
Prill Tower
PH11 Tower
Predryer
Predryer
Dryer
Dryer
Cooler
Cooler
Prill Tower
Prill Tower
Prill Tower
Cooler
Cooler
Granulator
Control Equipment
ELOC* Tray Scrubber
Entrainment Scrubber
ELOC Two-Tray Scrubber
Collection Hood/WFFSd
(Op.l)
Full How «FFSd
(Op.2)
Reduced Flow WFFSd
(Op.3)
ELK Tray Scrubber
Entrainment Scrubber
ELOC Tray Scrubber
Entrainment Scrubber
ELOC Tray Scrubber
Entrainment Scrubber
ELOC - Uncontrolled
Collection Hood/WFFSd
Full How WFFSd
(Op.2)
ELOC Tray Scrubber
Entrainment Scrubber
ELOC Entrainment Scrubber
Cost of Control*
Device
24.000
38,000
215,000
124,000
558.000
158,000
26,000
38,000
26,000
38,000
35,000
37,000
124,000
564.000
26,000
39,000
57,000
Major Equip-
ment Cost
60,000
71 ,000
340,000
352.000
940.000
249,000
61 .000
71 ,000
61 ,000
71 ,000
59,000
69,000
148,000
350,000
943,000
63,000
72,000
122,000
Total Installed6
Cost
184,000
219.000
1.040,000
1.090.000
2.900.000
767.000
187,000
217,000
187,000
217,000
181.000
210,000
454,000
1,080,000
2.910.000
192.000
221 ,000
374.000
alncludes only the control device cost.
Includes cost of control device, fans, pumps, motors, starter, downcoroers, and stacks.
C8ased on the component capital cost factors for direct and indirect cost from Table 7-7.
dWetted fibrous filter scrubber.
•ELOC « Existing Level of Control
7-19
-------
TABLE 7-8. CAPITAL COSTS OF CONTROL ALTERNATIVES FOR MODEL PLANTS
Plant'
No.
HI
H2
H3
LI
12
L3
SI
32
03
Reg."
Alt.
1
2
3
4
4a
1
2
3
4
4a
1
2
3
4
4d
1
2
3
4
1
2
3
4
1
2
3
4
1
2
1
2
1
2
Case
H1-1
HI -2
H1-3
HI -4
Hl-4a
H2-1
H2-2
H2-3
H2-4
H2-4a
H3-1
H3-2
H3-3
H3-4
H3-4a
Ll-1
Ll-2
L1-3
LI -4
L2-1
L2-2
L2-3
L2-4
L3-1
L3-2
L3-3
L3-4
Sl-1
Gl-2
G2-1
G2-2
G3-1
G3-Z
Tot»lc
Equipment
Cost
400,000
411,000
423,000
1.010,000
320,000
657,000
669,000
721,000
1,800,000
564,000
396,000
900,000
1,050,000
2,680,000
794,000
188,000
219,000
363,000
664,000
327,000
356,000
559,000
1.150,000
663,000
696,000
1,060,000
2.220,000
183,000
193,000
366.000
386.000
549.000
579,000
Difference 1n
d Total Installed
Total Cost for Emission Reductions
Installed Alternative Rela- Achieved by Control
Cost five to ELOC* J Alternative
1,230.000
1,270,000
1 ,300.000
3.110,000
986,000
2.020.000
2,060.000
2,220,000
5,560,000
1,740,000
2.760,000
2.770,000
3,230,000
8.140,000
2.450,000
580,000
675,000
1,120,000
2,050,000
1,010.000
1,100.000
1.720,000
3.550,000
2.060.000
2.140,000
3,260.000
6.860,000
565.000
594,000
1,130,000
1.190.000
1,700,000
1 ,780,000
_
3.3
5.7
153
-20
-
2.0
9.9
175
-14
-
0.4
17
195
-11
-
16
93
253
-
8.9
70
251
-
3.9
58
233
-
5.1
-
5.3
-
4.7
MoVyr
649
725
776
801
801
1,297
1,448
1.553
1,600
1,600
1.945
2.173
2,330
2,400
2.400
824
938
964
976
1,547
1.874
1,927
1,951
3,707
4.218
4,336
4,390
17,464
17,531
34,927
35,061
52,391
52.593
(ton/yr)
715
799
356
383
833
1.430
1,597
1.713
1,764
1.764
2,144
2,396
2,569
2,647
2,647
908
1,034
1,063
1,076
1,316
2,067
2,125
2,151
4.086
4,652
4,782
4,341
19,250
19,333
38.500
38,665
57,750
57,969
Emissions for
Alternative
Relative to
ELOC* S
.
12
20
24
24
-
12
20
24
24
-
12
20
24
24
-
14
17
19
-
14
17
19
-
14
17
19
-
0.4
-
0.4
-
0.4
*Model Plants from Table 7-1.
Control Alternatives from Table 7-3.
cIncludes cost of control device, fans, punps, motors, starters, downcomers and stacks.
Based on the component capital cost factors for direct and Indirect costs. Table 7-7.
Based on the emission factors detailed in Table 7-2.
•ELOC « Existing Level of Control
7-20
-------
TABLE 7-9. BASIS FOR SCRUBBER ANNUALIZED COST ESTIMATES (1980)
Direct Operating Costs
Utilities
Water Condensate from solution formation
processes assumed available free of
charge3
Electricity $.04/kwh
Operating Labor $17.45/hr14
Operating Hours
Process Equipment 7,728 hours/year
Scrubbers 7,728 hours/year
Each scrubber requires one eighth of
an operator while in operation^
Maintenance 5.5 percent of capital investment
Capital Charges
Capital Recovery Factor 13.15 percent of capital investment
Taxes and Insurance 5.0 percent of capital investment '
Administrative Overhead 2.5 percent of capital investment
Recovery Credit $55/Mg ($50/ton)
aThis condensate would contribute to a plant's water pollution loading, if not
used by scrubbers. Since costs of treatment and disposal are avoided, the
assumption that it is available free of charge is conservative.
Based on a 15-year equipment life15 and a 10 percent interest rate.
7-21
-------
Electricity costs were based on the power required to run the
electric motors used to operate fans and pumps. A 60 percent efficiency
was assumed for pumps. Brake horsepower for the motors was determined
18
by using power curves from cost estimating manuals; motor efficiency
of 90 percent was assumed to provide the total power requirement. The
annual cost of electricity was based upon an electricity cost of $.04/kwh.
Annual labor cost for the operation of the control equipment is the
product of the total labor rate14 ($17.45/hr), the operating hours per
year of the control process {7728 hr/yr), and the number of operators
required to run the control equipment (1/8 operator/unit). The annual
labor cost to operate a single control device is estimated to be $16,860/yr.
The ammonium nitrate recovered by the various control devices was
estimated to have a net credit of $55/Mg AN ($50/ton AN) recovered,
?o
based on current industry practice. Typically, scrubber liquor is
maintained at a concentration of 15 percent AN. A purge stream is drawn
off to maintain this 15 percent AN concentration. Usually, this purge
liquor is used to redissolve off-size/off-specification AN prills and
granules, which produces a liquor of 30 to 60 percent AN. This solution
is commonly sent to a surge tank, where it is mixed with the 83 percent
AN solution produced in the neutralizer. It is then concentrated in the
evaporator process, and sent to the solids forming process equipment.
The cost of recovering ammonium nitrate was based on concentrating a 30
percent AN solution to 99.4 percent. The recovery credit was determined
by taking the difference of the cost of concentrating the ammonium
?l
nitrate and the present sale price of $100/Mg ($91/ton). The amount
of ammonium nitrate recovered annually by the control alternatives,
presented in Table 7-8, was used to determine the annual recovery credit.
The annualized cost for the control of individual sources (i.e.,
cooler, dryer, predryer, prill tower, and granulator) in the 363 Mg/day
(400 TPD) model plants is presented in Table 7-10. This table presents
the annual cost for electricity to operate the control device, and the
7-22
-------
TABLE 7-10.
ANNUALIZED COST FOR THE CONTROL OF INDIVIDUAL SOURCES
IN 363 Hg/Day (400 TPD) MODEL AMMONIUM NITRATE PLANTS
Plant Type
High Density
Prilling
Low Density
Prilling
Granulation
Source of
Emissions
Cooler
Cooler
Prill Tower
Prill Tower
Prill Tower
Prill Tower
Predyer
Predryer
Dryer
Dryer
Cooler
Cooler
Prill Tower
Prill Tower
Prill Tower
Cooler
Cooler
Granulator
Control Equipment
ELOC* Tray Scrubber
Entrapment Scrubber
ELOC Two-Tray Scrubber
Collection Hood/UFFSe
(Op.l)
Full Flow WFFSe
(Op. 2)
Reduced Flow WFFSa
<0p.3)
ELOC Tray Scrubber
Entrapment Scrubber
ELOC Tray Scrubber
Entrainment Scrubber
ELOC Tray Scrubber
Entrainment Scrubber
ELOC - Uncontrolled
Collection Hood/WFFS*
(Op.l)
Full Flow UFFS6
(Op.2)
ELOC Tray Scrubber
Entrainment Scrubber
ELOC Entrainment Scrubber
Electricity*
Cost
6,200
22.600
118,000
30.800
150,000
35,900
5,700
21 ,800
5,700
21 ,800
5,700
21,000
4.400
32,000
151,000
5,900
22,000
43,500
Total Annual6
Cost
72,000
97,000
405.000
331 ,000
924,000
254,000
72,000
96,000
72,000
96,000
70,000
93,000
123,000-
331,000
927,000
73.000
97.000
158,000
Net Annual Cost0
After Recovery
Credits
41 ,000
63,000
400,000
323,000
914,000
244,000
41,000
62,000
41 ,000
62,000
40,000
59 .000
123,000
329,000
923,000
43,000
63,000
-775,000d
a8ased on 7728 hr/yr operation at $.04/kwh.
Includes electricity, labor, capital charge, taxes, insurance and maintenance based on Table 7-9
cThe cost after applying a recovery credit of S55/«g AN (JSO/ton AN).
^Negative indicates credit is greater than cost.
eWetted fibrous filter scrubber.
•ELOC « Existing Level of Control
7-23
-------
annualized cost of the control device before and after consideration of
recovery credits. The net annual cost of the control devices, including
recovery credits, ranges from $40,000 for existing control of emissions
from a cooler, to $923,000 for the full flow wetted fibrous filter
scrubber used to control emissions from prill towers. The negative
annual cost for the granulator scrubber, -$775,000, indicates that the
recovery credit is greater than the operating costs.
The annual costs of controlling individual sources, as shown in
Table 7-10, were combined to determine the annual costs of the control
alternatives. These annual costs are presented in Table 7-11; the
annual costs of the control alternatives with and without recovery
credits are presented.
7.1.2.4 Effect of Control Alternatives on Product Cost. The
impact of the control alternatives on the price of the product was also
determined and is presented in Table 7-11. This cost impact indicates
the cost per unit of ammonium nitrate produced. It is calculated by
dividing the net annual cost of the control alternative by the annual
model plant production.
Based upon a product selling cost of $91/ton, the percentage impacts
on product cost could range from 2 to 8 percent for high density plants
and 2 to 11 percent for low density plants. For granulation plants the
impact would be negative, since the value of the recovered product
exceeds control equipment costs.
7.1.2.5 Cost Effectiveness. Cost effectiveness, presented in
Table 7-11, is used as a means of comparing control alternatives. It is
defined as the total annualized cost of the pollution control system,
divided by the quantity of pollutant removed by the system. The cost
effectiveness of the control alternatives can be compared directly to
the existing level of control by using the following equation.
Cost Effectiveness = i
px
7-24
-------
TABLE 7-11.
ANNUALIZED COST AND COST EFFECTIVENESS OF CONTROL
ALTERNATIVES FOR MODEL AMMONIUM NITRATE FACILITIES
Effect on Cost
. pof Product
Plant Reg. Net Annual Cost (Including recovery
No. Alt. Case S/yr credit)
Without With j
Recovery Recovery"
Credit Credit
HI 1 H1-1 476,000 440,000
2 Hl-2 502,000 462,000
3 HI -3 428,000 386.000
4 HI -4 1.020.000 976,000
4a H1-4a 350.000 306.000
H2 1 H2-1 300.000 729.000
2 H2-2 840,000 760,000
3 H2-3 724,000 638,000
4 H2-4 1,330,000 1,740,000
4a H2-4a 612,000 525,000
H3 1 H3-1 1,110,000 1,010,000
2 H3-2 1,160.000 1.040,000
3 H3-3 1,030,000 903,000
4 H3-4 2.660.000 2.530.000
4a H3-4a 344,000 713,000
Li 1 Ll-1 214,000 168,000
2 Ll-2 263,000 213,000
3 Ll-3 410,000 359,000
4 Ll-4 711,000 659,000
L2 1 L2-1 335,000 244,000
2 L2-2 406,000 303,000
3 L2-3 614.000 507,000
4 L2-4 1.210,000 1,110,000
L3 1 L3-T 637,000 433,000
2 L3-2 768,000 536,000
3 L3-3 T, 150, 000 906.300
4 L3-4 2.330,000 2.090.000
G1 1 G1-1 231,000 -732.000
2 61-2 254,000 -712.000
62 1 62-1 462.000 -1.460.000
2 G2-2 508.000 -1,420,000
63 1 G3-1 693,000 -2.200,000
2 G3-2 762.000 -2.140,000
aModel Plants from Table 7-1.
Control alternatives fron Table 7-3.
S/Mg
3.77
3.34
3.31
8.36
2.61
3.12
3.25
2.73
7.44
2.25
2.87
2.97
2.58
7.22
2.03
2.38
3.65
6.14
11.29
2.08
2.60
4.35
9.47
1.64
2.05
3.46
7.97
-6.25
-6.10
-6.25
-6.10
-6.25
-6.10
S/ton
3.42
3.58
3.00
7.58
2.37
2.83
2.95
2.48
6.75
2.04
2.60
2.69
2.34
6.55
1.34
2.61
3.31
5.57
10.24
1.39
2.36
3.95
3.59
1.49
1.86
3.14
7.23
-5.67
-5.53
-5.67
-5.53
-5.67
-5.53
Costf
Effectiveness
(Including recovery
credit)
S/Mg
679
637
497
1224
381
562
525
411
1087
327
517
478
387
1055
297
204
227
372
676
143
162
263
567
117
127
209
477
-42
-41
-42
-41
-42
-4',
S/ton
616
578
451
1110
346
510
476
372
986
297
469
434
351
957
259
185
206
333
613
134
147
239
514
106
115
189
433
-38
-37
-33
-37
-38
-37
Cost Effectiveness
Relative to ELOC»
(Including recovery
credit)
S/Mg
.
287
-422
3516
-880
-
205
-355
3337
-674
-
131
-306
3331
-605
-
394
1358
3222
-
259
938
2849
-
201
749
2420
-
266
-
266
-
266
S/ton
.
262
-383
3190
-798
-
186
-322
3027
-611
-
119
-273
3022
-590
-
357
1232
2923
-
235
351
2585
-
182
680
2195
-
241
-
241
-
241
cBased on annual ized cost estimates outlined in Table 7-10.
dUsing a credit of $55/Mg (S50/ton) and the emissions reductions detailed
eNet Annual ized Cost
Mg (ton) AN produced per year
fNet Annual ized Cost
ig (ton) of particulates removed per year
9Net Annual ized Cost of Alternative - Net Annual fzed
Cost for
in Table
7-9.
Existing Control
Mg (ton) pattlculates removed By alternative -rig (ton) participates removed by ELOC
*ELOC « Existing Level of Control
7-25
-------
C = Net annualized cost to remove a quantity of pollutant (P ) by
A A
alternative x.
CE = Net annualized cost to remove a quantity of pollutant (P£) to
meet the specified existing level of control.
Cost effectiveness values indicate that Alternative 3, Alternative 1,
and Alternative 2 are the most cost effective alternatives for high
density prilling, low density prilling and granulation plants, respectively.
7.1.2.6 Base Cost of Facility. To provide a perspective in which
control costs can be viewed, capital and annual cost for the entire
ammonium nitrate plants are presented. Table 7-12 provides the base
capital and annual cost of ammonium nitrate plants for the range of
plant sizes investigated. All costs are installed costs, and all facilities
are uncontrolled.
Capital costs of the plants were based upon plant costs obtained
pp po
from published sources and cost estimating manuals. ' These costs
are for the entire plant, which include solution formation, concentration,
and solids formation equipment. Costs are given for various model plant
sizes, but no differentiation is made between low density prilling, high
density prilling and drum granulation.
The average total capital investment for new ammonium nitrate
plants ranged from $3.54 million for a 181 Mg/day (200 TPD) facility to
$9.48 million for a 1089 Mg/day (1200 TPD) facility.
The annual cost for ammonium nitrate plants was based upon information
obtained from an economic analysis of water pollution regulations.
This economic analysis presents annual costs as percentages of annual
sales. From this source it was determined that a small 181 Mg/day (200
TPD) facility spends 99 percent of the sales value of the product on
annual expenses. For a large 1089 Mg/day (1200 TPD) plant, operating
costs amount to 74 percent of the sales value of the product. The
annual cost for operation of the ammonium nitrate plants ranges from
$5.80 million for a 181 Mg/day (200 TPD) facility to $26.00 million for
a 1089 Mg/day (1200 TPD) facility.
7-26
-------
TABLE 7-12. BASE COSTS OF AMMONIUM NITRATE PLANTS10'22'23
Plant Size Annual Cost
Mg/Day (TPD) Capital Cost $ Millions
Cost RangeAverage Cost
($ millions) ($ millions)
181 (200) 2.95 - 4.13 3.54 5.80
363 (400) 4.01 - 5.90 4.96 10.90
726 (800) 6.12 - 9.09 7.61 19.40
816 (900) 6.72 - 9.68 7.95 21.10
1089 (1200) 7.39 - 11.60 9.48 26.00
7-27
-------
7.1.3 Existing Facilities
Substantial costs could be incurred by applying these control
alternatives to existing facilities. Existing facilities may not have
the space to install the required pollution control equipment where it
is needed. Room may have to be made for new control equipment, either
by moving process components or installing pollution control equipment
in the available space and ducting the emissions to the process. Both
of these alternatives would incur additional costs.
Installation costs for pollution control equipment could be more
expensive for existing facilities than for new facilities. Installation
of a collection hood within an existing prill tower, for example, may
require partial dismantling of the prill tower to install the device,
thus increasing installation costs. In addition, existing facilities
might have to be reinforced to support the weight of the pollution
control equipment; this, too, would increase installation costs. Since
these costs are site specific, no costs were determined for applying
these controls to existing facilities.
7.2 OTHER COSTS CONSIDERATIONS
7.2.1 Costs Imposed by Water Pollution Control Regulations
Possible sources of wastewater in ammonium nitrate plants are the
condensate from the neutralizer and evaporator exhausts and solutions
from air pollution control equipment. No wastewater is generated from
the solids forming processes, and any effluents from the air pollution
control equipment are always recycled to the process for economic reasons.
Thus, no additional wastewater treatment costs are expected due to the
air pollution control equipment.
7.2.2 Costs Imposed by Solid Waste Disposal Requirements
Because of to the high solubility of ammonium nitrate, any solid
wastes can be dissolved and used as liquid fertilizer, or be dissolved
and recycled to produce more solids. Thus, no solid process waste is
anticipated from an ammonium nitrate plant.
7-28
-------
7.3 REFERENCES
1. Letter from Kahn, P. A., Peter A. Kahn and Co., to Brown, P., GCA
Corporation. October 30, 1979. p. 1. Cost of Monsanto Enviro-
Chem Mist Eliminator.
2. Letter and attachment from Pepper-Cherry, D., Monsanto Enviro-Chem,
to Rader, R., Radian Corporation. June 6, 1980. p. 6. Information
on mist eliminator operation and cost.
3. Telecon. Brown, P., GCA Corporation, with Podhorski, J., Joy
Industrial Equipment Co. March 12, 1979. Costs and other topics
concerning scrubbers.
4. Telecon. Brown, P., GCA Corporation, with Ewach, J., Koch Engineering.
May 7, 1979. Cost and operation of two-tray scrubber.
5. Ammonium Nitrate Emission Test Report: C. F. Industries, The
Research Corporation, EMB Report 79-NHF-10, November 1979.
6. Telecon. Brown, P., GCA Corporation, with Hosier, R. W., W. W. Sly
Manufacturing Co. March 15, 1979. Costs of wet scrubbers.
7. Neveril, R. B. (GARD, Incorporated.) Capital and Operating Costs
of Selected Air Pollution Control Systems. Prepared for U. S.
Environmental Protection Agency. Research Triangle Park, N. C.
Publication No. EPA-450/5-80-002. December 1978. pp. 4-57 through
4-64.
8. Reference 7, p. 4-53.
9. Reference 7, P. 4-61.
10. Reference 7, pp. 4-20, 4-23.
11. Reference 7, p. 4-73.
12. Economic Indicators. Chemical Engineering. 8_7(8): 7. April 21,
1980.
13. Reference 7, pp. 3-2 through 3-11.
14. Memo from Apple, C., Radian Corporation, to file. June 4, 1980.
2 p. Cost of operating labor.
15. Reference 7, pp. 3-10 through 3-19.
16. Internal Revenue Service. Tax Information on Depreciation, 1979
Edition. Publication No. 534. Washington, D. C., U. S. Government
Printing Office, 1978. 38 p.
7-29
-------
17. Memo from Apple, C., Radian Corporation, to file. September 19,
1980. 6 p. Capital and Annual Costs of control devices.
18. Reference 7, pp. 4-56, 4-61.
19. Memo from Apple, C., Radian Corporation, to file. June 20, 1980.
3 p. Determination of recovery credits for ammonium nitrate
facilities.
20. Memo from Apple, C., Radian Corporation, to file. June 20, 1980.
3 p. Survey of industry to characterize scrubber liquor concen-
tration.
21. Current Prices of Chemicals and Related Materials. Chemical
Marketing Reporter. j?18(3):34. July 21, 1980.
22. Chemical Engineering (ed.) Sources and Production Economics of
Chemical Products, Second Edition. New York, McGraw-Hill Publishing
Company, 1979. pp. 122-124.
23. Guthrie, K.M., Process Plant Estimating Evaluation and Control.
Solona Beach, California, Craftsman Book Company of America, 1974.
603 p.
24. David, M.L., J.M. Malk and C.C. Jones. (Development Planning and
Research Associates, Inc.) Economic Impact of Costs of Proposed
Effluent Limitation Guidelines for the Fertilizer Industry.
(Prepared for U.S. Environmental Protection Agency.) Washington,
D.C. Publication No. EPA-230/1-73-010. October 1973. p. 11-14.
25. Telecon. Smith, Vince, RTI, with Stelling, J., Radian Corporation.
July 14, 1980. Projections for new plant growth in the ammonium
nitrate industry.
26. Search, W.J., et. al. (Monsanto Research Corporation.) Source
Assessment: Nitrogen Fertilizer Industry Water Effluents. (Prepared
for U.S. Environmental Protection Agency.) Washington, D.C.
Publication No. EPA-600/2-79-019b. January 1979. p. 27.
7-30
-------
APPENDIX A
Summary of Test Data
Six ammonium nitrate plants were tested by the EPA to evaluate
emissions and control techniques at solid ammonium nitrate production
facilities. A description of each plant, its major emission points, and
the operations tested are presented in this Appendix. The facilities
tested at the plants are listed below:
Plant A
Neutralizer scrubber inlet and outlet
Calandria evaporator outlet
Combined calandria - air swept falling film evaporator outlet
High density prill tower scrubber inlet and outlet
Rotary drum cooler scrubber inlet and outlet
Plant B
Rotary drum granulator scrubber inlet and outlet
Rotary drum cooler outlet
Plant C
Rotary drum predryer outlet
Rotary drum dryer outlet
Rotary drum cooler outlet
Plant D
Air swept falling film evaporator outlet
Combined evaporator - pan granulator scrubber inlet and outlet
Rotary drum precooler outlet
Chain mill (crusher) outlet
Combined precooler - chain mill scrubber outlet
Rotary drum cooler outlet
Plant E
Rotary drum cooler scrubber inlet and outlet
Plant Z
Low density prill tower scrubber inlet and outlet and bypass
Rotary drum predryer outlet
A-l
-------
Rotary drum dryer outlet
Combined predryer - dryer scrubber outlet
Fluidized bed cooler scrubber inlet and bypass
Three tests were performed on each of these facilities to determine
ammonium nitrate (AN) particulate and ammonia mass emissions. All the
ammonium nitrate and ammonia emission data presented in this Appendix
were determined by using a modified EPA Reference Method 5, which is
described in detail in Appendix B. Ammonium nitrate emissions were
determined with a specific ion electrode which analyzes for nitrate
ions. The total ammonia concentration was determined with a specific
ion electrode or by direct nesslerization (a colorimetric method). The
amount of ammonia emitted was determined by taking the difference of
total ammonia and nitrate results. All tests were performed at facilities
that operate with an excess of ammonia.
In addition to ammonium nitrate and ammonia, magnesium mass emissions
were measured at the prill tower scrubber inlet and outlet at Plant A.
EPA Test Methods 1 through 4 were used to determine other characteristics
of the gas stream, sampling points, gas velocity, volumetric flowrate
and gas moisture content, required for mass emission determinations.
Scrubber discharge stacks were monitored by using EPA Reference Method 9
to determine the opacity of the emissions.
The inlets to most of the scrubbers were tested to determine
particle size distributions. Cascade impactors made by several manufacturers
were used during this testing program. The methods used to determine
particle size distributions conformed to the specific manufacturer's
recommended procedures and requirements of the Emission Measurement
Branch of EPA.
A-2
-------
A.I Plant A
A.1.1 Process Overview
Plant A produces high density ammonium nitrate prills and various
types of ammonium nitrate solutions. The plant was designed to produce
567 Mg/day (625 TPD) of prilled ammonium nitrate.
Two parallel neutralizes are fed nitric acid and ammonia or ammonia
rich off-gases from the on-site, once-through urea solution plant, and
produce an 85 percent ammonium nitrate solution. This ammonium nitrate
solution is concentrated to 99+ percent in two stages of concentration.
The first stage is a steam heated calandria and the second stage is an
air swept falling film evaporator. A magnesium nitrate additive produced
in a reactor is injected between the two stages of concentration.
The 99+ percent ammonium nitrate melt from the evaporators is
sprayed down through the prill tower, where the droplets are cooled and
solidified into prills by a countercurrent induced air flow. The prills
are then conveyed to a rotary drum cooler, which reduces the temperature
and removes nominal amounts of moisture from the prills by using a
countercurrent flow of heat-tempered, refrigerated air. Prills are then
screened; product sized prills are either bulk loaded or bagged, and
off-size prills are recycled to a weak scrubber liquor evaporator. A
calandria evaporator is used to concentrate recycled scrubber liquor and
redissolved offsize product rejected from the screening operation.
A.1.2 Emission Control Equipment
The emission control equipment used at Plant A is summarized
below. Each neutralizer uses an internal Brinks H-V mist eliminator,
followed by a venturi scrubber and a cyclonic separator. Emissions from
the two evaporators are normally ducted to a Koch valve tray scrubber
along with the prill tower emissions. Emissions from the recycle liquor
calandria evaporator and the magnesium additive reactor are usually
ducted to the Koch valve tray scrubber, too. However, during this
testing program only prill tower emissions were controlled by the Koch
valve tray scrubber; all other facilities normally controlled by
A-3
-------
this scrubber were vented to the atmosphere. Prill tower emissions are
ducted down from the top of the prill tower to the Koch scrubber located
at ground level.
Exhaust from the rotary drum cooler is divided into two streams;
each stream enters a separate spray chamber scrubber. The air exiting
each spray chamber is again divided into two streams, each of which
enters a separate cyclonic separator. The four separator outlets are
then combined into two before being discharged to the atmosphere. The
screening, conveying, and bagging areas are all uncontrolled.
A.1.3 Facilities Tested
The facilities tested at Plant A are listed below:
Neutralizer scrubber inlet and outlet
Calandria evaporator outlet
Combined calandria and air swept falling film evaporator outlet
Prill tower Koch valve tray scrubber inlet and outlet
Prill cooler spray chamber inlet and cyclonic separator outlets
Opacity observations and particle size measurements were performed
at some of the facilities. Particle size was measured with a Sierra
Cascade Impactor, but all of the particulate matter was caught in the
pre-collector. Thus, no reliable size distribution information was
obtained. A discussion of the testing at each facility follows, including
any problems that occurred during testing.
A.1.3.1 Neutralizer
The results of the mass emission tests performed at the inlet and
outlet of the neutralizer venturi scrubber are presented in Tables A-la
and A-lb. EPA test methods for high water content gas streams were
followed. The combined opacity of the two neutralizer scrubber plumes
were monitored and are presented in Table A-2. No opacity was observed
from this scrubber.
A-4
-------
There were several problems encountered during the neutralizer
scrubber tests. A leak check of the sampling train after the first
inlet run revealed a significant leak; as a result, the Run No. 1 inlet
sample volume and flow rate are not included in the averages. Runs No.
2 and 3 had relatively high isokinetic percents.
The ammonium nitrate (AN) emissions reported here may be somewhat
higher than what actually exists because of interference in the nitrate
ion analysis. The specific ion electrode analysis (SIE) method used to
detect nitrate ion concentration is subject to positive error if the
background ion concentration is high relative to the nitrate concentration.
The very high concentration of NH~ compared to AN in the neutralizer gas
stream could be sufficient to produce a positive interference in the AN
analysis. Also, ammonia emissions out of the scrubber were greater than
ammonia emissions entering the scrubber. This implies that ammonia is
stripped out of the scrubber liquor; the reason for this is unclear.
A.1.3.2 Calandria Evaporator Outlet
Only mass emission tests were performed at the calandria evaporator
outlet. The results of these tests are presented in Tables A-3a and
A-3b. Due to the extremely high moisture content in this duct, the
sampling was limited to the use of an in-stack orifice on one port and
only one sampling point at the center of the duct.
There was an excessive amount of NH- compared to AN in this outlet,
which may have created interference in the SIE analysis, causing the AN
emissions to be excessively high.
A.1.3.3 Combined Calandria and Air Swept Falling Film Evaporator Outlet
Results of the mass emission tests at the combined calandria and
air swept falling film evaporator outlet are presented in Tables A-4a
and A-4b. A major discrepancy exists in the mass emission results
obtained from the calandria outlet and the combined calandria and air
swept falling film evaporator outlet. The emissions from the calandria
outlet were much higher than the emissions from the combined calandria
and air swept falling film evaporator outlet. This is probably due to
A-5
-------
interference in the SIE analysis, resulting from the high NH_ concentration
at these test points.
A.1.3.4 Prill Tower Koch Valve Tray Scrubber Inlet and Outlet
The inlet and outlet of the Koch Scrubber was tested for magnesium
emissions along with ammonium nitrate and ammonia. The results of these
tests are presented in Tables A-5a and A-5b. Visible emissions from the
scrubber discharge stack were also monitored. These opacity readings
are presented in Table A-6.
During testing, isokinetic percentages for the prill tower scrubber
outlet test Runs No. 1 and 2 were relatively high; this was probably due
to an operator error. The ammonia emissions for Run 3 are anomalously
low and are not included in the average of the ammonia data. The low
emissions were probably due to the fact that the ammonia injection
mechanism was off during this run.
A.1.3.5 Prill Cooler Scrubber Inlet and Outlet
The results of testing at the prill cooler inlet and outlet are
presented in Tables A-7a and A-7b. Emissions from the two cyclone
separator outlets were combined to determine the total outlet emissions.
Since the flow rates from these two scrubbers were not equal, the emissions
from the combined outlet were calculated by using a weighted average
based on flow rates. The opacity of the two prill cooler scrubber
systems exhaust plumes were monitored simultaneously. The results of
the opacity readings are presented in Table A-8. No problems were
encountered during testing at this scrubber.
A.1.4 Process Operation During Testing
The process was operating at 61 to 81 percent of design capacity
during testing.
Several problems occurred during the testing program. The pH in
the neutralizer required constant monitoring and adjusting and the prill
tower NH3 injection mechanism was off during Run No. 3 of the prill
tower tests. Also, there were problems with the C02 compressor in the
urea plant which caused the plant to shut down.
A-6
-------
Therefore, the NH3 feed to the neutralizer had to be supplied from the
NH_ vaporizers, instead of from the urea NH- rich off gas. This problem
occurred before the third test of the prill tower scrubber and was
corrected before the third test started. Finally, a decreased production
demand led to a substantial production reduction in the air swept falling
film evaporator between test 1 and 2 on this unit.
A-7
-------
TABLE A-la.
PLANT A: SUMMARY OF EMISSION TEST RESULTS
FOR THE NEUTRALIZER SCRUBBER (METRIC)
Test No.
General Data
Date
Isokinetic (X) In/Out
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidity
Exhaust Characteristics
Flowcate inlet:
(dnmj/min) outlet:
Temperature inlet:
(K) outlet:
Moisture (» voT) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (kPa)
Liquor pH (Ave.)
Liquor AN Cone. (X) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(g/dnmj) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (X)
Ammonia Emissions
Ammonia Cone. inlet:
(g/anm } outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
t'g/kg) outlet:
Collection Efficiency (X)
la
6/19/79
92.74/110.1
10.2
309
34
.7887
10.71
405
374
99.53
94.23
2
6/20/79
113.7/114.9
10.5
303
57
8.938
8.555
408
373
94.43
95.01
Venturi - cyclonic separator
12.4
8.73
6.6
681.0
2.542
32.22
1.696
3.1434
0.16542
94.7
285.3
220.4
134.9
146.9
13.2
14.3
Negative
16.1
8.80
7.1
53.27
2.492
28.57
1.321
2.7385
0.12663
95.4
398.5
412.2
213.6
221.9
20.5
20.9
Negative
3
6/20/79
126.6/112.8
10.4
305
58
7.383
9.241
405
372
95.24
94.85
scrubber
14.2
3.89
7.3
62.83
2.144
27.83
1.226
2.6913
0.11862
95.6
529.7
593.1
234.4
339.1
22.7
32.3
Negative
Ave.
u
120.2D/112.6
10.4
306
50
8.162b
9.502
406
373
94.84
94.70
14.2
8.81
7.0
55.60b
2.400
27.23
1.416
2.6329
0.13693
94.8
379.0
400.3
185.4
240.0
17.9
22.8
Negative
aSample train leak during Run 1.
Includes Run 2 and 3 only due to leak in Run 1.
A-8
-------
TABLE A-lb. PLANT A: SUMMARY OF EMISSION TEST RESULTS
FOR THE NEUTRALIZER SCRUBBER (ENGLISH)
Test No.
General Data
Date
Isokinetic (X) In/Out
Production Rate Tons/hr
Ambient Temp. °F
Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dscfra) outlet:
Temperature inlet:
(F°) outlet:
Moisture ("» vol) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (in. W.6. )
Liquor pH (Ave.)
Liquor AN Cone. (%) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (%)
Ammonia Emissions* <
Ammonia Cone. inlet:
{ gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency
la
6/19/79
92.74/110.
11.3
96
34
27.85
378.3
269
213
99.53
94.23
Venturi -
49.7
8.73
6.6
297.5
1.111
71.04
3.739
6.2867
2
6/20/79
1 113.7/114.9
11.5
86
57
315.6
302.1
275
212
94.43
95.01
cyclonic separator
64.5
8.80
7.1
23.28
1.089
62.98
2.912
5.4765
0.33088 0.25326
94.7
124.5
96.25
297.4
323.9
26.32
28.67
Negative
95.4
174.0
180.0
470.8
489.1
40.94
41.85
Negative
3
6/20/79
126.6/112.8
11.4
89
58
260.7
326.3
270
210
95.24
94.85
scrubber
57.2
8.89
7.3
27.46
.9370
61.36
2.704
5.3825
2.23723
95.6
231.3
259.0
516.8
747.6
45.33
65.59
Negative
Ave.
u
120.2D/112.6
11.4
90
50
288. 2b
335.6
271
212
94.84
94.70
57.1
8.81
7.0
24.30b
1.049
60.03
3.121
5.2658
0.27378
94.8
165.5
174.8
408.7,
529.0
35.35
45.63
Negative
aSample train leak during Run 1.
Includes Run 2 and 3 only, due to leak in Run 1.
A-9
-------
TABLE A-2. PLANT A: OPACITY READINGS ON THE
TWO NEUTRALIZER SCRUBBER STACKS
h.uc
I
o
6-19-79
Avcrii|>c Ujmctlty f-or
6 Minutes
Tlmu (Combined j'liitics)
0930-0935 0
0936-0941 0
0942-0947 0
094B-09S3 0
09S4-09S9 0
1000-1005 0
1006-1011 0
1012-1017 0
1018-1023 0
1024-1029 0
1030-1035 0
1036-1041 0
1042-1047 0
1048-10S3 0
1054-1059 0
1100-1105 0
1106-1111 0
1112-1117 0
1118-1123 0
1124-1129 0
1530-1535 0
1536-1541 0
1542-1547 0
1548-1553 0
1554-1559 0
1600-1605 0
1606-1611 0
1612-1617 0
1618-1623 0
1624-1629 0
Ditto
6-20-79
6-22-79
Time
1330-1335
1336-1341
1342-1347
1348-1353
1354-1359
1400-1405
1406-1411
1412-1417
1418-1423
1424-1429
1400-1405
1406-1411
1412-1417
1418-1423
1424-1429
1430-1435
1436-1441
1442-1447
1448-1453
1454-1459
Average Opacity l:or
6 Minutes
(ComliineJ I'hrn-s)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
TABLE A-3a. PLANT A: SUMMARY OF EMISSION TEST RESULTS AT THE
CALANDRIA EVAPORATOR OUTLET (METRIC)
Test No.
Genera] Data
Date
Isokinetic (%)
Production Rate (Mg/hr)
Ambient Temp. (K)
Ambient Moisture (Z) Relative Humidity
Exhaust Characteristics
Flowcate
(dnm-Ymin).
Temperature
(K)
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(9/kg).
Ammonia Emissions
Ammonia Cone.
(g/dnm3).
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
1
6/22/79
98.3
15.6
301
67
0.234
416
99.77
122.55
1.720
0.1102
1484.4
20.85
1.336
2-
6/22/79
105.1
15.9
304
49
0.235
417
99.78
119.3
1.679
0.1058
1279.4
18.01
1.1345
3
6/22/79
104.1
16.1
306
44
0.291.
416
99.73 -
132.2
2.307
0.1437
1506.8
26.30
1.638
Ave.
102.5
15.9
304
53
0.253
416
99.76
125.2
1.902
0.1198
1428.3
21.70
1.367
A-n
-------
TABLE A-3b. PLANT A: SUMMARY OF EMISSION TEST RESULTS
AT THE CALANDRIA EVAPORATOR OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate Tons/hr
Ambient Temp. °F
(5) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
Ob/ton)
Anmonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
1
6/22/79
98.3
17.2
82
67
8.272
289
99.77
53.48
3.792
0.22047
648.2
45.96
2.672
2
6/22/79
105.1
17.5
88
49
8.291
291
99.78
52.09
3.702
0.21154
558.7
39.70
2.269
3
6/22/79
104.1
17.7
92
44
10.280
290
99.73
57.72
5.086
0.28734
658.0
57.98
3.276
4
102.5
17.5
87
53
8.948
290
99.76
54.68
4.194
0.23966
623.7
47.84
2.734
A-12
-------
TABLE A-4a.
PLANT"A: SUMMARY OF EMISSION TEST RESULTS
AT THE COMBINED CALANDRIA AND AIR SWEPT
FALLING FILM EVAPORATOR OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (X)
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dnm-Vmin)
Temperature
(K)
Moisture (% Vol.)
Ammonium Nitrate Emissions
Parti cul ate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm^)
Emission Rate
(kg/hr)
Emission Factor
(9/kg)
1
6/22/79
113.2
18.4
301
67
90
428
32.45
0.2565
1.392
0.0756
14.78
80.2
4.357
2
6/22/79
127.5
19.1
304
49
77
429
43.38
0.2739
1.269
0.0666
12.42
57.5
3.019
3
6/22/79
111.4
19.1
306
44
91
430
35.71
0.2638
1.439
0.0756
18.37
100.2
5.255
Ave.
117.4
18.7
304
53
86
429
37.18
0.2647
1.369
0.0726
15.22
78.7
4.171
A-13
-------
TABLE A-4b.
PLANT A: SUMMARY OF EMISSION TEST RESULTS
AT THE COMBINED CALANORIA AND AIR SWEPT
FALLING FILM EVAPORATOR OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate Tons/hr
Ambient Temp. °F
(%} Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (*. Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
1
6/22/79
113.2
20.3
82
67
3196
311
32.45
0.1120
3.068
0.15113
6.458
176.9
8.714
2
6/22/79
127.5
21.0
88
49
2728
313
43.38
0.1196
2.797
0.13319
5.423
126.8
6.038
3
6/22/79
111.4
21.0
92
44
3213
315
35.71
0.11.52
3.173
0.15110
3.02
220.8
10.51
Ave.
117.4
20.8
87
53
3046
313
37.18
0.1156
3.018
0.14510
6.646
173.5
8.341
A-14
-------
TABLE A-5a.
PLANT A: SUMMARY OF EMISSION TEST RESULTS
FOR THE PRILL TOWER SCRUBBER (METRIC)
Test No.
General Data
Date
Isokinetic (%) In/Out
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidity
5 Opacity
Exhaust Characteristics
Floweate inlet:
(dnm /min) outlet:
Temperature inlet:
(K) outlet:
Moisture (% vol) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop
Liquor pH (Ave.)
Liquor AN Cone. (?) (Ave.)
Ammonium Nitrate Emissions
Participate Cone, inlet:
(g/dnmj) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (%}
Ammonia Emissions*
Ammonia Cone. inlet:
(g/dnnT) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (%)
Magnesium Emissions
Magnesium Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (X)
1
5/8/79
99.3/108.4
19.1
299
60
12.8
7300
7510
307
309
2.049
3.033
Koch Valve Tray
2.64
7.21
34
0.07175
0.03512
31.43
15.82
1.650
0.831
49.7
1.2610
0.1988
552.0
89.5
28.98
4.70
83.8
0.0006256
0.0001113
0.2740
0.0501
0.01438
0.00263
81.7
2
5/8/79
98.9/110.8
19.1
298
60
15.2
7190
7470
306
308
2.466
2.56
Scrubber
2.71
7.28
35
0.06816
0.03446
29.41
15.43
1.544
0.811
47.5
1.2641
0.1806
545.2
80.9
28.61
4.24
85.2
0.0002097
0.00006295
0.0905
0.0282
0.00475
0.00148
68.8
3
5/9/79
99.3/103.5
19.3
299
65
17.2
7320
7600
306
306
2.542
2.874
2.56
6.50
27
0.07228
0.03794
31.75
17.31
1.643
0.896
45.5
0.0460
0.0632
20.2
28.8
1.05
1.49
Negative
0.0002659
0.0001194
0.1168
0.0545
0.00605
0.00282
53.3
Ave.
99.2/107.6
19.2
299
62
15.1
7270
7530
306
308
2.352
2.822
2.66
7.00
32
0.07075
0.03585
30.86
16.16
1.612
0.844
47.6
1.2568
0.1920
547.5
86.7
28.6
4.53
84.2
0.0003652
0.0000974
0.1593
0.0440
0.00832
0.00230
72.4
*Run 3 results were low and were not included in the average.
A-15
-------
TABLE A-5b.
PLANT A: SUMMARY OF EMISSION TEST RESULTS
FOR THE PRILL TOWER SCRUBBER (ENGLISH)
Test Ho.
General Data
Date
Isokinetic (%} In/Out
Production Rate Tons/hr
Ambient Temp. °F
Relative Humidity
X Opacity
Exhaust Characteristics
Flowrate inlet:
(dscfm) outlet:
Temperature inlet:
(F°) outlet:
Moisture (% vol) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (in. W.G.)
Liquor pH (Ave.)
Liquor AN Cone. (%) {Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (%)
Ammonia Emissions*
Ammonia Cone. inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (X)
Magnesium Emissions
Magnesium Cone. inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (5)
1
5/8/79
99.3/108.4
21.0
78
60
12.8
257,800
265,200
93
96
2.049
3.033
Koch Valve Tray
10.6
7.21
34
0.03136
0.01535
69.29
34.88
3.299
1.661
49.7
0.5506
0.08680
1217
197.3
57.95
9.40
83.8
0.0002734
0.0004862
0.6041
0.1105
0.02877
0.00526
81.7
2
5/8/79
99.8/110.8
21.0
77
60
15.2
253,900
263,700
91
95
2.466
2.56
Scrubber
10.9
7.28
35
0.02979
0.01506
64.83
34.02
3.087
1.620
47.5
0.5520
0.07886
1202
178. 3
57.22
8.48
85.2
0.00009165
0.00002751
0.1995
0.06218
0.00950
0.00296
58.8
3
5/9/79
99.3/103.5
21.3
78
65
17.2
258,500
258,500
91
91
2.542
2.874
10.7
6.50
27
0.03159
0.01658
69.99
38.16
3.286
1.792
45.5
0.0201
0.02760
44.55
63.53
2.092
2.98
Negative
0.0001162
0.00005217
0.25747
0.12007
0.01209
0.00564
53.3
Ave.
99.2/107.6
21.1
78
62
15.1
256,700
256,800
92
94
2.352
2.822
10.7
7.00
32
0.03092
0.01565
68.02
35.64
3.224
1.688
47.6
0.5488
0.08386
1207
191.1
57.21
9.05
84.2
0.0001596
0.00004256
0.35116
0.09696
0.01664
0.00460
72.4
*Run 3 results were low and were not included in the average.
A-16
-------
TABLE A-6. PLANT A.
OPACITY READINGS ON THE
PRILL TOWER SCRUBBER OUTLET
Ilille
5-7 79
HA
S-B-79
TinH!
1400-1405
1406-1411
1412-1417
1418-1423
1424-1429
1430-1435
1436-1441
1442-1447
1448-1453
1454-1459
1505-1510
1511 1516
1517-1522
1523-1528
1529-1534
1535-1540
IS41-I546
1547-1552
1553-1558
1559-1004
1030-1035
IMS-II20
1121-1126
1127-1132
11.33-1130
1139-1144
II4S-IISO
1151-1157
1157-1202
1103- 1 208
Avcnijie (t|>in ily
Tor ft Minutes
2.3
7.7
ft. 3
8.8
6.5
5.4
6.6
6.6
5.6
4.8
7.5
8.8
6.9
5.4
5.4
7.7
8.3
2.3
5.0
6.S
6.2
11.6
14.6
14.4
14.2
12.5
11.6
12.5
13.B
11.7
11.3
Ikilc
5-8-79
lltm
5-9-79
Time
1500-1505
1506-1511
1512-1517
1518-1523
1524-1529
1530-1535
1536-1541
1542-1547
1548-1553
1554-1559
I605-1610
1611-1616
1617-1622
1623-1628
1629-1634
1635-1640
1641-1646
I647-I6S2
1653-1658
1659-1704
Avcr.i|>e
1050-1056
1057-1102
1103-1108
1109-1114
1115-1120
1121-1126
1127-1132
1133-1138
1139-1144
1145-1150
Avcrnyf
Pur 6 Minnies
15.4
15.8
15.0
15.4
17. 1
14.8
16.0
14.6
14.6
14
11
11
11
16
15.6
16.6
16.3
16.9
16.7
16.7
15.2
18,
14,
17,
17,
17.
18
19.0
17.5
14.8
17.3
Avcriij'o
12.8
17.2
-------
TABLE A-7a.
PLANT A: SUMMARY OF EMISSION TEST RESULTS
FOR COOLER SCRUBBER (METRIC)
Test No.
General Data
Date
Isokinetic (5)
Production Rate (Mg/hr)
Ambient Temp. (K)
% Relative Humidity
1
5/10/79
.99.3/97.8
19.1
308
45
2
5/11/79
99.6/100.7
19.1
305
50
3
5/11/79
98.2/101.7
18.8
310
37
Ave.
99.0/100.1
19.0
308
44
Exhaust Characteristics
Flowrate inlet:
(dnm3/min) outlet:
Temperature inlet:
(K) outlet:
Moisture (% Vol.) inlet:
out!et:
Control Device Characteristics
Device Type
Pressure Drop (kPa)
Liquor pH (Ave.)
Liquor AM Cone. (S)(Ave.)
Ammonium Mltrate Emissions
Particulate Cone, inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (5)
Ammonia Emissions
Ammonia Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (%)
896
974
62
48
1.879
2.290
881
953
63
46
1.447
3.182
878
939
63
48
0.755
2.428
Spray Chamber
1.02
6.37
0.23
0.2803
0.0222
15.07
1.299
0.791
0.0682
91.4
negative
0.00405
negative
0.11721
negative
0.0062
Buell Cyclonic Separator
0.995 0.970
6.46 6.45
0.25 0.32
0.2787
0.03613
14.74
2.067
0.774
0.1085
86.0
0.00827
0.00902
0.4372
0.2586
0.02295
0.0136
40.7
0.3286
0.0154
17.32
0.867
0.923
0.04618
95.0
0.0112
0.0119
0.5905
0.3331
0.0315
0.0178
885
956
63
48
43.6
1.360
2.634
0.995
6.43
0.26
0.2956
0.02467
15.70
1.414
0.828
0.0746
91.0
0.00965
0.00829
0.5124
0.2371
0.0271
0.0113
58.2
A-18
-------
TABLE A-7b.
PLANT A: SUMMARY OF EMISSION TEST RESULTS
FOR COOLER SCRUBBER (ENGLISH)
Test No.
General Data
Date
Isokinetic (%) In/Out
Production Rate Tons/hr
Ambient Temp. °F
(5) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dscfm) outlet:
Temperature inlet:
(F°) outlet:
Moisture (% Vol.) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (in. W.G.) Avg.
Liquor pH (Ave.)
Liquor AN Cone. (%) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (%)
Ammonia Emissions
Ammonia Cone. inlet:
(gr/dscf } outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency
1
5/10/79
99.3/97.8
21
95
45
31650
34410
143
118
1.879
2.290
2
5/11/79
99.6/100.7
21
89
50
31120
33660
144
114
1.447
3.182
3
5/11/79
99.2/101.7
20.7
98
37
31020
33140
145
118
0.755
2.428
Ave.
99.0/100.1
20.9
94
44
31260
33740
144
117
1.360
2.634
Spray Chamber - Buell Cyclonic Separator
4.1
6.37
0.23
0.1225
0.00971
33.22
2.864
1.582
0.1364
91.4
negative
0.00177
negative
0.2584
negative
0.0123
4.0
6.46
0,25
0.1218
0.01579
32.50
4.556
1.547
0.2169
86.0
0.003613
0.00394
0.9639
0.5701
0.0459
0.0272
40.7
3.9
6.45
0.32
0.1436
0.00673
38.19
1.912
1.845
0.09235
95.0
0.00490
0.0052
1.3017
0.7343
0.0629
0.0355
43.6
4.0
6.43
0.26
0.1292
0.01078
34.62
3.118
1.656
0.1492
91.0
0.00421
0.00362
1.1297
0.5228
0.0541
0.02264
58.2
A-19
-------
TABLE A-8. PLANT A: OPACITY READINGS ON THE PRILL
COOLER EAST AND WEST SCRUBBER OUTLETS
Average Opacity For
6 Minutes
Time (East Outlet/West Outlet)
1100-1105 0/0
1106-1111 0/0
1112-1117 0/0
1118-1123 0/0
1124-1129 0/0
1130-1135 0/0
1136-1141 0/0
1142-1147 0/0
1148-1153 0/0
1154-1159 0/0
1200-1205 0/0
1206-1211 0/0
1212-1217 0/9
1218-1225 0/0
1224-1229 0/0
1230-1255 0/0
1236-1241 0/0
1242-1247 0/0
1248-1253 0/0
1254-1259 0/0
1310-1515 0/0
1316-1321 0/0
1522-1327 0/0
1328-1553 0/0
1334-1539 0/0
1340-1345 0/0
1346-1351 0/0
1352-1557 0/0
1358-1405 0/0
1404-1409 0/0
A-20
-------
A.2 Plant B
A.2.1 Process Overview
Plant B produces various ammonium nitrate solutions and granulated
solid ammonium nitrate. The solids production was designed for 363
Mg/day (400 TPD) of ammonium nitrate.
An 83 percent ammonium nitrate solution is produced in the neutralizer.
This solution is split into two streams, with some going to the solution
product area; the remainder proceeds to the two-stage concentrator,
where the solution is concentrated to 99+ percent. The ammonium nitrate
melt from the concentrator is sprayed into the rotary drum granulator.
In the granulator a flow of chilled air countercurrent to the granule
flow solidifies and cools the granules. A set of screens separates the
product size granules from offsize granules. Product size granules
proceed to a rotary drum cooler where refrigerated air further cools the
granules. The cooled granules are then coated and either bagged or bulk
loaded.
A.2.2 Emission Control Equipment
The emission control equipment used at Plant B consists of an
entrainment scrubber for granulator exhausts, and wet cyclones for
cooler exhausts. Emissions from the neutralizer, concentrators, coater,
crushing and screening operations and conveying equipment are discharged
to the atmosphere uncontrolled.
This particular rotary drum granulator has been fitted with a
"knock out" or "settling" chamber on the end of the drum where the air
exits. Some of the ammonium nitrate particulate that would normally go
to the scrubber is removed in this chamber. The exhaust from the granulator
is then ducted to a Joy "Type D" Turbulaire Scrubber, where it is combined
with an ammonium nitrate weak liquor scrubber solution. Emissions from
the rotary drum cooler are ducted to two parallel wet cyclones. There
is a water spray located in the duct itself and three sprays in each
cyclone.
A-21
-------
A.2.3 Facilities Tested
Two sources were tested at Plant B, the rotary drum granulator
scrubber inlet and outlet, and the rotary drum cooler outlet. A Brinks
Impactor was used to determine particle sizes at the cooler outlet and
the granulator scrubber inlet. EPA Method 9 was used to observe plume
opacity levels from the granulator scrubber exhaust stack.
The results of the mass emission tests on the granulator scrubber
are presented in Tables A-9a and A-9b. Particle size results are shown
in Figure A-1, and opacity observations are presented in Table A-10.
The cooler mass emission test results are given in Table A-lla and
A-llb; the particle size results are presented in Figure A-2.
A.2.3.1 Testing Problems
During the testing program, several of the test runs were discontinuous
due to the excessive particulate loading at the rotary drum granulator
scrubber inlet and the rotary drum cooler outlet sampling locations.
A.2.4 Process Operation During Testing
The process was operating at 87 to 125 percent of design capacity
during the testing.
Minor plant upsets occurred during the entire testing program.
Problems with controlling the fan damper on the rotary drum granulator
and scrubber, and a malfunctioning scrubber liquor level controller
voided the first days of testing. On day three (March 7, 1979), only
three out of four granulator nozzles were operative due to the limited
quantity of ammonium nitrate (AN) melt available. The third particulate
concentration test on the inlet and outlet to the rotary drum granulator
scrubber was conducted at this lower production rate. The fourth
granulator nozzle was brought back on line during the early afternoon
and continued on line for the remainder of the testing.
On day four (March 8, 1979), the granulator was put on total recycle,
with no additional AN melt being added due to an excessively low level
in the head tank. This happened between tests and should not affect the
results of the testing of the rotary drum cooler.
A-22
-------
On day five (March 9, 1979), the compressor on the inlet air cooler
of the granulator went out of service, causing granulator temperatures
to become excessively high. Trouble continued with the fan damper
serving the granulator and scrubber. The combined effect of these two
problems eventually led to a rise in the granulator bed temperature to a
point where the granules were agglomerating, forming "rocks". At this
point, the granulator was shut down until the problem was corrected.
Testing did not resume until steady state conditions were again attained.
A-23
-------
TABLE A-9a.
PLANT B: SUMMARY OF EMISSION TEST RESULTS
FOR THE ROTARY DRUM GRANULATOR SCRUBBER (METRIC)
Test No.
Ave.
General Data
Date 3/7/79
Isokinetic (%) In/Out 102.6/98.1
Production Rate (Mg/hr) 13.15
Ambient Temp. (K) 292
(%) Relative Humidity 40
Exhaust Characteristics
Floweate inlet: 1,172
(dmrr/min) outlet: 1,091
Temperature inlet: 74
(K) outlet: 311
Moisture (Z vol) inlet: 2.0
outlet: 2.9
Control Device Characteristics
Device Type Joy "Type D"
Pressure Drop (kPa) 2.41
Liquor pH (Ave.) 6.33
Ammonium Nitrate Emissions
Participate Cone, inlet: 30.46
(g/dnnr) outlet: 0.06
Emission Rate inlet: 2,141.9
(kg/hr) outlet: 3.928
Emission Factor inlet: 162.9
(g/kg) outlet: 0.299
Collection Efficiency (*) 99.8
Ammonia Emissions*
3/7/79 3/8/79
103.1/97.5 101.7/101.
15.82 18.60
298 289
23 41
1,230 1,391
1,158 1,245
86 82
316 319
2.0 2.0
3.7 7.9
Turbulair Scrubber
2.54 3.19
5.88 6.51
31.73 29.11
0.040 0.047
2,341.7 2,429.5
2.779 3.511
148.0 130.6
0.176 0.189
99.9 99.8
102.5/99.2
15.86
293
34.7
1,264
1,165
81
315
2.0
4.8
2.71
6.24
30.43
0.049
2,304.4
3.41
147.2
0.221
99.8
Ammonia Cone. inlet:
(dnnT) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (5)
15.45
0.0183
1085.7
6.046
82.55
0.090
99.89*
0.2817
0.0550
20.78
3.810
1.32
0.240
81.75
1.193
0.270
99.52
20.19
5.35
1.085
79.72
5.640
0.156
402.0
11.11
29.74
0.675
97.7*
*Inlet Run No. 1 acid fraction results are inconsistently higher than other test results,
may have had sample carryover in the impinger.
A-24
-------
TABLE A-9b.
PLANT B: SUMMARY OF EMISSION TEST RESULTS
FOR THE ROTARY DRUM GRANULATOR SCRUBBER (ENGLISH)
Test No.
1 2
3 Ave.
General Data
Date
Isokinetic (i) In/Out
Production Rate Tons/hr
Ambient Temp. °F
(5) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dscfm) outlet:
Temperature inlet:
(°F) outlet:
Moisture (5 vol) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (in. M.6.)
Liquor pH (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
Ob/ton) outlet:
Collection Efficiency (5)
Ammonia Emissions*
3/7/79
102.6/98.1
14.5
66
40
41,401
38,521
166
100
2.0
2.9
Joy "Type D1
9.7
6.33
13.311
0.026
4,723.6
8.58
325.8
0.59
99.8
3/7/79
103.1/97.5
17.4
76.6
23
43,442
40,887
186
109
2.0
3.7
3/8/79
101.7/101,
20.5
60.9
41
49,120
43,969
180
115
2.0
7.9
Turbulair Scrubber
10.2 12.3
5.88 6.51
13.868 12.725
0.017 0.020
5,163.9 5,357.6
5.96 7.54
296.8 261.3
0.34 0.37
99.9 99.8
102.5/99.2
17.5
67.8
34.7
44,654
41,126
177
108
2.0
4.8
10.9
6.24
13.301
0.021
5,081.7
7.36
294.6
0.43
99.8
Ammonia Cone. inlet:
( gr/dscf } outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (%)
6.745
0.008
2,393.6
2.64
165.1
0.18
99.89*
0.123
0.024
45.8
8.4
2.53
0.48
81.75
0.521
0.118
219.4
44.5
10.7
2.17
79.72
2.463
0.068
886.3
24.5
59.48
1.35
97.7*
*Inlet Run No. 1 acid fraction results are inconsistently higher than other test results,
may have had sample carryover in the impinger.
A-25
-------
PO
en
0.4
0.3
0.2
0.1
0.01
O.I
90
-1
% Greoler ihon Slated Site
50 10
, , r
JL
JL
O Run I -IS
A Run 2 - IS
D Run 3 - IS
JL
.1 L
10 50 90
Wciglil % less ihan Staled Sire
98 99
0.01
99.9 99.99
Figure A-l. Plant B: Particle size results at the
rotary drum granulator scrubber inlet.
-------
TABLE A-10.
PLANT B: OPACITY READINGS FROM THE ROTARY
DRUM GRANULATOR SCRUBBER OUTLET STACK
Tine
16:40:15-16:45
16:46:15-16:52
16:52:15-16:58
16:58:15-17:04
17:04:15-17: 10
17: 10:15-17:16
17:16:15-17:2:
17:22:15-17:23
Average
09:20-09:25:45
09:26-09:31:45
09:32-09:J7:45
Averaje
09:52: 15-00:53
09: 53: 15-10:04
10:04: 15-iO: :0
;0: 10: 15-10: la
13: IS: 15-13:22
10:22: 15- 10:25
Average
10:33:i5-10:39:iO
10:39:45-10:45:30
10:45.45-10:51:30
10:51:45-10:57:30
Averajs
11:08:IS-IL:U
H: 14: 15-11:20
Avenze
11:29-11:31:45
11: J2-U:37:i5
:i: 38-ll:43;4i
Average
11.50: l5-Ll:Si
U:56. 15-12:02
12 -02:15- 11:18
12:08: 15-12:14
12: 14: 15-12:20
12:20: IS"-12:Z6
»2:2S: 15-12:32
12: 32:15-12:13
12:38. 15-12:44.
12;i4: 15-12:50
12:50:15-12:56
12:56:15-13:02
Awerij-
13: 35-13:40:45
13:il-l3:'-0:45
13:47-13:52:45
13:53-13:53:45
Averag-
14:03-14:08:45
14:09-14:14.45
14:15-14:20:45
'.4:21-14:26:45
14:27-14:32:45
Aver i^s
14:33-14:33:^.5
U:39-14:4i:i.S
14:45-14:50:4$
14:51-l4:Jo:4,5
Average
Average opacity
toe — & ain
iacenraU, (*) Dies
5.0 03-07-JJ
5.0
5.0
5.0
5.2
5.4
5.2
5.6
5.2
12.9 J3-08-79
13.5
13.5
13. J
14.3
15.3
14.3
14.4
14. J
15.4
14. 4
17.3
15.0
15.3
15.3
16. J
I? 9
15. 3
16.3
15. s
'14.6
12.9
14. i
14. »
15. J
14.2
16 5
17.5
13.1
'.3.4
13.5
12. t
13. 1
14.4
13. i
14.3
19.4
15. J
14.4
17.1
16.5 * OpacitT .jbierviciors cscocdeJ iron cne rocjcv
15.4 dcua ^raauljcor scruober nuclei scjci cor-
16. J respond to MRI :sic l-ORDC jt che uacoa-
17.3 croLle-i outlet ac "ae racary Jrui coaler.
12.9
14. »
15. J
14. -i
15. i
1S.J
13-5
15.1
A-27
-------
TABLE A-lla. PLANT B: SUMMARY OF EMISSION TEST RESULTS
AT THE COOLER OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%)
Production Rate (Mg/hr)
Ambient Temp. (K)
(5) Relative Humidity
Exhaust Characteristics
Flowcate
(dnm/min)
Temperature
(K)
Moisture (2 vol)
Ammonium Nitrate Emissions
Participate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions3
1
3/8/79
93.7
18.96
297
29
579
310
2.1
4.354
151.3
8.0
2
3/9/79
100.7
18.87
296
71
565
315
1.5
3.970
134.6
7.1
3
3/9/79
100.4
18.96
298
55
556
317
1.8
4.178
139.4
7.4
Ave.
98.3
18.93
297
52
567
314
1.8
4.167
141.8
7.5
Ammonia emissions are all negative, there were more nitrate than ammonia ions present.
A-28
-------
TABLE A-llb.
PLANT B: SUMMARY OF EMISSION TEST RESULTS
AT THE COOLER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate Tons/hr
Ambient Temp. "F
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfin)
Temperature
Moisture (% vol)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions8
1
3/8/79
93.7
20.85
75.3
29
20,464
99
2.1
1.903
333.8
16.0
2
3/9/79
100.7
20.82
73.0
71
19,948
107
1.5
1.735
296.7
14.3
3
3/9/79
100.4
20.85
77.3
55
19,620
111
1.8
1.826
307.1
14.7
Ave.
98.3
20.84
75.2
52
20,011
106
1.8
1.321
312.5
15.0
aAmmonia emissions are all negative, there were more nitrate than ammonia ions present.
A-29
-------
Welglil % Greater than Staled Size
99
10
7
C
(
5
4
3
u
5
K .
V 1
e
,g
c!o J! 0.7
O ,o
t
a
°- 0.5
0.4
0.3
0.2
n i
.99, 99.91 99 9B 90 50 10 1 Q.C
lilt 1 1 1
L-^s— — — — "~7 "
t=^-~^=^^' ' I
/
I
f
J
/
. -A
— —
_
—
-. —
O Run 1 -CO
A Run 2 -CO
0 Run 3 -CO
-
i i i till
0.01
10 50 90
Weight % Lets than Staled Size
98 99
99.9
99.99
Figure A-2. Plant B: Particle size results at the rotary drum cooler outlet.
-------
A.3 Plant C3
A.3.1 Process Overview
Plant C produces ammonium nitrate solutions and low density ammonium
nitrate prills. The plant was designed for a production rate of 161
Mg/day (200 TPD) of prilled ammonium nitrate.
The 83 percent ammonium nitrate solution from the neutralizer is
concentrated to 95 percent in a vacuum evaporator. The 95 percent
ammonium nitrate melt is then pumped to the top of the prill tower,
where it is sprayed down through multiple spray heads. Prills formed in
the tower are conveyed to the rotary drum predryer, dryer and cooler,
respectively. The predryer and dryer use heated air flowing countercurrent
to the product flow to remove moisture from the prills. The cooler uses
chilled air to reduce prill temperature.
The prills are then screened. Offsize prills are dissolved and
recycled to the vacuum evaporator; product sized prills are coated and
either bagged or bulk loaded.
A.3.2 Emission Control Equipment
The emission control equipment used at Plant C consists of a condenser
for neutralizer overheads, tray scrubbers for the predryer, dryer and
cooler, and scrubbers to control emissions from bagging operations.
Emissions from the prill tower, evaporator, screening, coating and
conveying equipment are all exhausted to the atmosphere uncontrolled.
The exhausts from the predryer and dryer are sent to a common Sly
tray scrubber. Cooler emissions are controlled by a second Sly tray
scrubber. The exhausts from both tray scrubbers are ducted to a single
discharge stack.
A.3.3 Facilities Tested
Only the outlets (scrubber inlets) from the predryer, dryer and
cooler were tested. These facilities were tested to determine mass
emissions and particle size distributions. The results of the emission
tests are presented in Tables A-12a through A-14b. Particle size
results are presented in Figures A-3 through A-5.
A-31
-------
A.3.3.1 Testing Problems
Most of the test runs were discontinuous due to excessive loading
of dust particles. This excessive amount of dust was found to produce
material accumulation of up to 2 inches in the bottom sections of some
of the test ducts. The heavy loading of large particles caused plugging
of probe nozzles and pitot tubes, making the sampling extremely difficult
and resulting in several shut-downs throughout the three test runs.
During test 2 on the predryer, the glass probe liner separated from
the union connector and the prescribed leak check conducted after completion
of the run failed. For test 3 on the predryer one of the glassware
connectors broke. The connector was replaced and the run was resumed.
During the testing of the dryer, several glassware connectors
broke. When this occurred, the sampling was stopped and the connector
was replaced.
A.3.4 Process Operation During Testing
The process was operating at an average of 107 percent of design
capacity during testing.
Several problems were encountered during testing. There was a
short process shutdown during the first test run which disrupted testing.
Also, it was very difficult to monitor process parameters during the
testing. Heavy rains caused the moisture content in the prills to
increase. The prills became very sticky, causing the process recording
instruments to plug up.
-32
-------
TABLE A-12a. PLANT C: SUMMARY OF EMISSION TEST RESULTS
AT THE PREDRYER OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%)
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dnm /min)
Temperature
(K)
Moisture (% vol)
Ammonium Nitrate Emissions
Participate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(gAg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(gAg)
1
3/29/79
93
7.56
292
53
245
328
2.24
7.94
117
15.5
Negative
2
3/30/79
92
8.65
292
53
232
334
2.24
4.58
63.5
7.35
Negative
3
3/30/79
98
8.06
292
55
162
325
2.24
6.18
59.9
7.45
1.207
11.7
1.45
Ave.
94
8.09
292
54
213
329
2.24
6.22
80.3
10.1
a
data presented, negative difference.
A-33
-------
TABLE A-12b. PLANT C: SUMMARY OF EMISSION TEST RESULTS
AT THE PREDRYER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%}
Production Rate Tons/hr
Ambient Temp. °F
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture {% vol)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
1
3/29/79
93
8". 33
65.5
53
8661
131
2.24
3.47
258
31.0
Negative
2
3/30/79
92
9.54
66
53
8188
142
2.24
2.00
140
14.7
Negative
3
3/30/79
98
8.88
66
55
5703
126
2.24
2.70
132
14.9
.527
25.8
2.90
Ave.
94
8.92
65.8
54
7517
133
2.24
2.72
177
20.2
a
No data presented, negative difference.
A-34
-------
io.a
1=1 MS .U tl
.3 3 i9
PERCENT LESS THAN DIAMETER
Figure A-3. Plant C: Particle size results at the predryer outlet.
A-35
-------
TABLE A-13a. PLANT C: SUMMARY OF EMISSION TEST RESULTS
AT THE DRYER OUTLET (METRIC)
Test No.
General Data
Date
I so kinetic (%}
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dnm-Vmin)
Temperature
(K)
Moisture (% Vol.)
Ammonium Nitrate Emissions
Participate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
l
3/29/79
100
7.56
292
53
167
337
2.24
9.61
96.1
12.7
negative
2
3/30/79
101
8.65
292
50
140
345
2.24
19.2
161
18.7
3.298
27.76
3.205
3
3/30/79
97
8.06
292
51
257
339
2.24
1.51
23.3
2.90
0.401
6.17
0.765
Ave.
99
8.09
292
54
188
341
2.24
10.1
93.4
11.4
a
No data presented, negative difference.
A-36
-------
TABLE A-13b. PLANT C: SUMMARY OF EMISSION TEST RESULTS
AT THE DRYER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate Tons/hr
Ambient Temp. °F
(X) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (% vol)
Ammonium Nitrate Emissions
Parti cul ate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
1
3/29/79
100
8.33
65.5
53
5888
148
2.24
4.20
212
25.4
negative
2
3/30/79
101
9.54
66
53
4957
162
2.24
8.37
356
37.3
1.44
67.2
64.1
3
3/30/79
97
8.88
66
55
9060
151
2.24
0.561
51.4
5.79
0.175
13.6
1.53
Ave.
99
8.92
65.8
54
6635
154
2.24
4.41
206
22.8
a
No data presented, negative difference.
A-37
-------
10,0
PERCENT LESS THAN DIAMETER
Figure A-4. Plant C: Particle size results at the dryer outlet.
A-38
-------
TABLE A-14a. PLANT C: SUMMARY OF EMISSION TEST RESULTS
AT THE COOLER OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%)
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteristics
Flowrate
Temperature
(K)
Moisture (5 Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rats
(kg/hr)
Emission Factor
(g/kg)
1
3/29/79
104
7.56
292
53
217
323
2.24
8.74
109
14.5
negati ve
2
3/30/79
102
8.65
292
50
266
322
2.24
9.04
142
16.5
1.088
17.15
1.98
3
3/30/79
100
8.06
292
55
249
319
2.24
3.36
46.7
5.80
2.473
36.29
4.51
Ave.
102
8.09
292
53
244
321
2.24
7.05
99.3
12.3
a
No data presented, negative difference.
A-39
-------
TABLE A-14b. PLANT C: SUMMARY OF EMISSION TEST RESULTS
AT THE COOLER OUTLET (ENGLISH)
Test No'.
General Data
Date
Isokinetic (%}
Production Rate Tons/hr
Ambient Temp. °F
(%) Relative Humidity
Exhaust Characteristics
Fl owrate
(dscfm)
Temperature
Moisture (5 Vol.)
Ammonium Nitrate Emissions
Parti cu late Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
lib/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
1
3/29/79
10.4
8.33
65.5
53
7359
122
2.24
3.82
241
28.9
negati ve
2
3/30/79
102
9.54
67
50
9268
121
2.24
3.95
314
32.9
0.475
37.8
3.96
3
3/30/79
100
8.88
66
55
8666
115
2.24
1.47
109
11.6
1.08
30.0
9.01
Ave.
102
8.92
66.2
53
8431
119
2.24
3.08
219
24.5
a
No data presented, negative difference.
A-40
-------
TO.a
o
cr
5 1.0
-ua jj. a _•
.a -3
PERCENT LESS THAN DIAMETER
Figure A-5. Plant C: Particle size results at the cooler outlet.
A-41
-------
A.4 Plant D4
A.4.1 Process Overview
Plant D produces granulated ammonium nitrate using a pan granulator.
This plant has a design production rate of 363 Mg/day (400 TPD).
Approximately 90 percent ammonium nitrate solution is produced in a
two-stage neutralizer; consequently, less concentration is required.
The 90 percent ammonium nitrate solution from the neutralizer is combined
with recycled scrubber liquor and fed to an air swept falling film
evaporator, where it is concentrated to an essentially anhydrous ammonium
nitrate melt.
After concentration, an additive is injected into the melt. The
purpose of the additive is to surround the individual crystals formed
during the granulation process, which allows for expansion and contraction
through the various phase changes, while preventing granule disintegration.
The ammonium nitrate melt is sprayed onto a bed of seed material in
the pan granulator. All of the solid product leaving the pan granulator
enters a rotary drum precooler. Chilled air is used to cool the granules.
The cooled granules exiting the precooler are sent through an enclosed
chain mill lump breaker and delivered by bucket to the recycle screen.
Undersize granules are recycled to the pan granulator; oversize granules
are crushed and then recycled.
Correctly sized product leaving the recycle screen is sent through
the rotary drum product cooler. In the cooler, heat-tempered, refrigerated
air flows countercurrent to the product flow. Granules leaving the
cooler are once again screened, coated, and either bagged or bulk loaded.
A.4.2 Emission Control Equipment
The emission control equipment used at Plant D consists of an HV
Brinks unit on the first stage neutralizer, a Sly scrubber on the second
stage neutralizer, a variable-throat venturi scrubber on the evaporator
and pan granulator, a Buffalo Forge baffle type scrubber on the precooler/crusher
area, and two wet cyclones on the cooler. Exhausts from coating and
bagging operation are uncontrolled.
A-42
-------
The HV Brinks unit on the first stage neutralizer is an integral
part of the vessel. Mist removed by Teflon elements is returned directly
to the neutralizer.
The off-gas stream from the second stage neutralizer is controlled
by a Sly scrubber. The exhaust also passes through a mist eliminator
located at the exit point of the vent stack, before being discharged to
the atmosphere.
Both evaporator and pan granulator exhausts are controlled by a
single, adjustable-throat venturi scrubber. After passing through the
venturi, the air stream is sent through a cyclonic droplet separator.
A Buffalo Forge baffle-type scrubber controls emissions from the
precooler and crusher area. A dust pick-up on the bucket elevator also
exhausts emissions through this scrubber. The initial recycle screen,
the crusher screen, the crusher, and transfer points are all exhausted
through this scrubber.
The exhausts from the cooler pass through two wet cyclones in
parallel before being discharged to the atmosphere.
A.4.3 Facilities Tested
The facilities tested at Plant D are listed below:
Evaporator Outlet
Combined Evaporator-Pan Granulator
Venturi Scrubber Inlet and Outlet
Precooler Outlet
Chain Mill (Crusher) Outlet
Combined Precooler - Chain Mill Baffle Scrubber Outlet
Cooler outlet
All facilities were tested for ammonium nitrate (AN) particulate
and ammonia mass emissions. Opacity was observed from the scrubber
discharge stacks. Particle size measurements were performed at some of
the scrubber inlets, using an Anderson Cascade Impactor. A discussion
of the testing at each facility follows. Any problems encountered
during the testing are also discussed in the appropriate sections.
A-43
-------
A.4.3.1 Evaporator Outlet
The evaporator outlet was tested only for mass emissions. The
results of the testing are presented in Tables A-15a and A-15b. While
sampling at this point the operator had problems maintaining a constant
orifice pressure differential, resulting in high isokinetic sampling
ratios for the second and third runs.
A.4.3.2 Coabined Evaporator - Pan Granulator Venturi Scrubber Inlet
and Outlet
Results of the three mass emission tests are presented in Tables
A-16a and A.-165. Visible emissions from the venturi scrubber discharge
stack were monitored and are presented in Table A-17.
Also, mass emissions from the pan granulator outlet were determined
by taking the difference of the emissions obtained at the venturi scrubber
inlet and the emissions from the evaporator outlet. The results of
these calculations are presented in Tables A-18a and A-18b.
While sampling at the combined evaporator - pan granulator inlet,
the velocity pi tot tubes became clogged several times, requiring the use
of velocity pressure data obtained from the initial velocity traverse
for determination of orifice pressure drops. The fluctuating moisture
content of the flue gas, in addition to the other problems encountered,
caused the isokinetic sampling ratio to vary during the sampling run.
Also, cyclonic flow patterns were suspected at the combined evaporator -
pan granulataur inlet location, resulting in measured volumetric flow
rates ten to fifteen percent lower than actual volumetric flow rates.
Since emissions calculations are based on volumetric flow rates, these
are also believed to be low by ten to fifteen percent. Consequently,
the efficiency calculations would be expected to be less than the actual
efficiency.
A.4.3.3 Precooler Outlet
Precoolier outlet mass emission test results are presented in
Tables A-19a and A-19b. Particle size was also measured at the precooler
outlet. Results of the three particle size tests are presented in
A-44
-------
Figure A-6. There were no excess ammonia emissions measured at this
outlet; there were more nitrate ions present than ammonia in the sample.
A.4.3.4 Chain Mill (Crusher) Outlet
Results of mass emission tests at the chain mill outlet are presented
in Tables A-20a and A-20b. This is the only test performed at this
point.
A.4.3.5 Combined Precooler - Chain Mill Baffle Scrubber Inlet and Outlet
The results of the mass emission tests on the Buffalo Forge Baffle
Scrubber are presented in Tables A-21a and A-21b. Mass emissions from
the precooler and chain mill were summed to provide the scrubber inlet
values reported in this table. Visible emissions from the scrubber
discharge stack were monitored and are reported in Table A-22.
A.4.3.6 Cooler Outlet
The results of the mass emissions tests at the cooler outlet are
presented in Tables A-23a and A-23b. The particle size was also tested
at this outlet and is presented in Figure A-7.
There was no excess ammonia measured at this outlet; more nitrate
ions were present in the sample than ammonia.
A.4.4 Process Operation During Testing
The process was operating at 80 to 91 percent of design capacity
during testing. No abnormalities in process operation were noted
during the testing.
A-45
-------
TABLE A-!5a. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE EVAPORATOR OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%)
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteri sties
Flowrate
Temperature
(K)
Moisture (S Vol.)
Ammonium Nitrate Emissions
Participate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
1
11/7/78
1D4
13.34
299
25
39.71
365
55.2
0.2013
0.4808
0.036
0.4033
0.9616
0.072
2
11/8/78
122
13.34
296
34
37.38
369
57.9
C.1898
0.4264
0.032
0.4216
0.9480
0.071
3
11/8/78
112
13.79
303
21
29.66
374
59.8
0.2237
0.3992
0.029
0.4349
0.7757
0.056
Ave.
113
13.52
299
27
35.57
369
57.6
0.2050
0.4355
0.0325
0.4200
0.8936
0.0665
A-46
-------
TABLE A-15b. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE EVAPORATOR OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (X)
Production Rate Tons/hr
Ambient Temp. °F
(3) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
(F'J
Moisture (" Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
Ob/ ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf}
Emission Rate
Ob/hr)
Emission Factor
Ob/ ton)
1
11/7/78
104
14.7
78
25
1403
198
55.2
0.0879
1.06
0.072
0.1761
2.12
0.144
2
11/8/78
122
14.7
74
34
1321
205
57.9
0.0829
0.94
0.064
0.1841
2.09
0.142
3
11/8/78
112
15.2
86
21
1048
213
59.8
0.0977
0.88
0.058
0.1899
1.71
0.112
Ave.
113
14.9
79
27
1257
205
57.6
0.0895
0.96
0.065
0.1834
1.97
0.133
A-47
-------
TABLE A-16a.
PLANT D: SUMMARY OF EMISSION TEST RESULTS
FOR THE EVAPORATOR AND PAN GRANULATOR SCRUBBER (METRIC)
Test No.
Ave.
General Data
Date
Isokinetic (%) In/Out
Production Rate (Mg/hr)
Ambient Temp. (K)
(2) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dnnr/min) outlet:
Temperature inlet:
(K) outlet:
Moisture (% Vol.) inlet:
outlet:
Control Device Characteristies
Device Type
Pressure Drop (kPa)
Liquor pH (Ave.)
Ammonium Nitrate Emissions
Participate Cone, inlet:
(g/dnmj)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
outlet:
inlet:
outlet:
inlet:
outlet:
Collection Efficiency (%)
Ammonia Emissions
Ammonia Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (%}
11/7/78
78/101
13.3
299
25
225*
257
358
333
23.2
19.5
6.74
8.1
2.4726
0.0229
33.34*
0.35
2.501
0.027
98.9
0.1786
0.5125
2.404
7.911
0.181
0.593
negative
11/8/78
114/103
13.3
296
34
208*
248
362
333
27.9
19.5
11/8/78
101/101
13.8
303
21
216*
261
363
332
26.8
19.0
Venturi Scrubber
6.74 6.64
8.1 7.75
0.9548
0.0201
11.93*
0.30
0.895
0.023
97.5
0.7717
0.0094
9.99*
0.15
0.725
0.011
98.5
0.1163
0.3653
.452
.443
.109
.408
negative
.1408
.2631
.824
.119
0.132
0.299
negative
98/102
13.5
299
27
216*
255
361
332
26.0
19.3
6.72
7.98
1.3997
0.0174
18.42*
0.27
1.374
0.020
98.3
0.1452
0.3804
1.892
5.824
0.141
0.433
negative
•Cyclonic flow patterns suspected, volumetric flowsibeneved to be approximately 10 to 15
percent low.
A-48
-------
TABLE A-16b.
PLANT D: SUMMARY OF EMISSION TEST RESULTS
FOR THE EVAPORATOR AND PAN GRANULATOR SCRUBBER (ENGLISH)
Test No.
General Data
Date
Isokinetic W In/Out
Production Rate Tons/hr
Ambient Temp. °F
(%) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dscfm) outlet:
Temperature inlet:
(F°) outlet:
Moisture (% Vol.) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (in W.S.)
Liquor pH (Ave.)
Ammonium Nitrate Emissions
Parti cul ate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (Z)
Ammonia Emissions
Ammonia Cone. inlet:
(gr/dscf) outlet:
Emission Rate inlet:
Ob/hr) outlet:
Emission Factor inlet:
Ob/ ton) outlet:
Collection Efficiency (S)
1
11/7/78
78/101
14.7
78
25
7936*
9089
186
140
23.2
19.5
2
11/8/78
114/103
14.7
74
34
7355*
8773
192
140
27.9
19.5
3
11/8/78
101/101
15.2
86
21
7619*
9214
194
138
26.8
19.0
Ave.
98/102
14.9
79
27
7637*
9025
191
139
26.0
19.3
Venturi Scrubber
27.1
8.1
1.0807
0.010
73.51*
0.78
5.001
0.053
98.9
0.0780
0.2238
5.30
17.44
0.361
1.186
negative
27.1
8.1
0.4173
0.0088
26.31*
0.66
1.79
0.045
97.5
0.0508
0.1595
3.20
12.00
0.218
0.316
negati ve
26.7
7.75
0.3373
0.0041
22.02*
0.32
1.449
0.021
98.5
0.0615
0.1149
4.02
9.08
0.264
0.597
negative
27.0
7.98
0.6118
0.0076
40.61*
0.59
2.747
0.040
98.3
0.0634
0.1661
4.17
12.84
0.281
0.866
negative
*Cyclonic flow patterns suspected, volumetric flows believed to be approximately
10 to 15 percent low.
A-49
-------
TABLE A-17. PLANT D: OPACITY READINGS AT THE VENTURI SCRUBBER STACK
TEST NO. 12 3
GENERAL DATA
Date
Time
11/7
1110-1310
11/7
1600-1700
. 11/8
0915-1115
11/3
1345-1530
Steam Dispersion
Distance (Ft) 80 68 100 47
SIX MINUTE INTERVAL
AVERAGE OPACITY (%}
1 5
2 5
3 7
4 7.5
5 5
6 5
7 5
3 6
9 5
10 6
11 5
12 7
13 5
14 5
15 5
16 5
17 5
18 5
19 5
20 6
10
9.5
11
11
3
10
11.5
10.4
11.5
10
_
-
-
—
-
—
_
_
-
-
3
11
9
10
10
10
9
10
10
10
10
10
10
10
10
10
10
-12
10
10
10
10
10
10
10
10
10
10
10
9
8
10
10
9
10
10
10
10*
-
-
* 3 Minute Interval
A-50
-------
TABLE A-18a. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE PAN GRANULATOR OUTLET3 (METRIC)
Test No.
General Data
Date
Production Rate (Mg/hr)
Ambient Temp. (K)
(") Relative Humidity
1
11/7/78
13.3
299
25
2
11/8/78
13.3
296
34
3
11/8/78
13.8
303
21
Ave.
13.5
299
27
Exhaust Characteristics
Flowrate
(dnm3/min)
Ammonium Nitrate Emissions
Parti cul ate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
185"
2.962
32.86
2.465
0.1301
1.442
0.108
171°
1.123
11.51
0.863
0.0492
0.504
0.038
186°
0.859
9.59
0.696
0.0939
1.048
0.076
1.648
17.99
1.341
0.0911
0.998
0.074
aDetermined from the difference of the evaporator and combined evaporator-pan granulator data.
Cyclonic flow suspected at the combined inlet.
A-51
-------
TABLE A-18b. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE PAN GRANULATOR OUTLET3 (ENGLISH)
Test No.
General Data
Date
Production Rate Tons/hr
Ambient Temp. 3F
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
Ob/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf}
Emission Rate
Ob/hr)
Emission Factor
(Ib/ton)
1
11/7/78
14.7
78
25
6533b
1.2934
72.45
4.929
0.0568
3.18
0.216
2
11/8/78
14.7
74
34
6034b
0.4904
25.37
1.726
0.0215
1.11
0.076
3
11/8/78
15.2
86
21
6571b
0.3752
21.14
1.391
0.0410
2.31
0.152
Ave.
14.9
79
27
6379b
0.7197
39.65
2.682
0.0398
2.20
0.148
Determined from the difference of the evaporator and combined evaporator -
pan granulator data.
Cyclonic flow suspected at the combined inlet.
A-52
-------
TABLE A-19a. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE PRECOOLER OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%}
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dnm3/min)
Temperature
(K)
Moisture (5 Vol.)
Ammonium Nitrate Emissions
Participate Cone.
(g/dron^)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions'1
1
11/9/78
100
13.52
295
26
611a
366
2.0
4.890
179.34
13.267
2
11/10/78
101
13.36
292
57
699a
356
2.0
5.985
251.14
18.832
3
11/10/78
98
13.25
297
52
811a
356
2.0
5.956
289.97
21.393
Ave.
100
13.36
295
45
707*
360
2.0
5.611
240.15
17.997
Suspected to be low due to only one traverse being performed.
Ammonia emissions are all negative, more nitrate ions than ammonia present.
A-53
-------
TABLE A-19b. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE PRECOOLER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate Tons/hr
Ambient Temp. °F
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions
1
11/9/78
100
14.9
72
26
21593a
200
2.0
2.1355
395.36
26.534
2
11/10/78
101
14.7
66
57
24707
181
2.0
2.6136
553.65
37.663
3
11/10/78
98
14.6
75
52
28666
182
2.0
2.6009
639.26
43.785
Ave.
100
14.7
71
45
24989
188
2.0
2.450
529.42
35.994
Suspected to be low due to only one traverse being performed during the tests.
Anmonia emissions are all negative, more nitrate ions than ammonia present.
A-54
-------
aa aj am aat
IQOC
aj
CUII4JUATTVE PSH CENT B* WEIGHT L£SS THAH(D«
Figure A-6. Plant D: Particle size results at the precooler scrubber inlet.
A-55
-------
TABLE A-20a. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE CHAIN MILL OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (X)
Production Rate (Mg/hr)
Ambient Temp. (K)
(%} Relative Humidity
Exhaust Characteristics
Flowrate
(dnm3/min)
Temperature
(K)
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
1
11/9/78
101
13.5
295
26
47.29
301
0.8
2.244
6.369
0.471
negative
2
11/10/78
101
13.3
292
57
39.59
300
1.6
1.754
4.169
0.313
0.0421
0.0998
0.0075
3
11/10/78
105
13.2
297
52
39.71
307
4.4
2.549
6.074
0.459
0.0094
0.0227
0.0015
Ave.
102
13.3
295
45
42.20
302
2.2
2.182
5.539
0.414
0.0172
0.0408
0.003
A-56
-------
TABLE A-20b. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE CHAIN MILL OUTLET (ENGLISH)
Test No.
General Oata
Date
Isokinetic (5)
Production Rate Tons/hr
Ambient Temp. °F
(%) Relative Humidity
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (5 Vol.) .
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
Ob/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
1
11/9/78
101
14.9
72
26
1671
83
0.8
0.9801
14.04
0.942
negati ve
2
11/10/78
101
14.7
66
57
1399
81
1.6
0.7658
9.19
0.525
0.0184
0.22
0.015
3
11/10/78
105
14.6
75
52
1403
93
4.4
1.1130
13.39
0.917
0.0041
0.05
0.003
Ave.
102
14.7
71
45
1491
85
2.2
0.9530
12.21
0.828
0.0075
0.09
0.006
A-57
-------
TABLE A-21a.
PLANT D: SUMMARY OF EMISSION TEST RESULTS
FOR THE CHAIN MILL AND PRECOOLER SCRUBBER3 (METRIC)
Test No.
General Data
Date
Isoklnetic (%} Out
Production Rate (Mg/hr)
Ambient Temp. (K)
{%) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dnm2/min) outlet:
Temperature
(K) outlet:
Moisture (SVol.) outlet:
Control Device Characteristics
Device Type
Pressure Drop (kPa)
Liquor pH (Ave.)
Ammonium Nitrate Emissions
Parti cul ate Con. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission factor inlet:
(g/kg) outlet:
Collection Efficiency (%)
Ammonia Emissions
Ammonia Cone.
(g/dnm3) outlet:
Emission Rate
(kg/hr) outlet:
Emission Factor
(g/kg) outlet:
1
11/9/78
102
13.5
295
26
659
733
317
3,4
2
11/10/78
102
13.3
292
57
739
732
317
4.0
Buffalo Forge
0.796
6.3
4.6845
0.0247
185.246
1.084
3.705
0.080
99.4
0.0087
0.3810
0.028
1.72
6.6
5.7397
0.0460
254.696
2.023
19.099
0.152
99.2
0.1001
4.391
0.330
3
11/10/78
102
13.2
297
52
852
766
318
4.9
Scrubber
1.69
6.0
5.7781
0.0332
295.325
1.529
22.297
0.116
99.5
0.1347
6.187
0.468
Ave.
102
13.3
295
45
750
744
318
4.1
1.39
6.3
5.4008
0.0345
245.089
1.547
18.367
0.116
99.4
0.0811
3.652
0.275
Inlet data is based on the combination of the chain mill and precooler data.
Ammonia emissions from the precooler are all negative.
A-58
-------
TABLE A-21b.
PLANT D: SUMMARY OF EMISSION TEST RESULTS
FOR THE CHAIN MILL AND PRECOOLER SCRUBBER3 (ENGLISH)
Test No.
General Data
Date
Isokinetic W Out
Production Rate Tons/hr
Ambient Temp. °F
(%) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dscfm) outlet:
Temperature
(F°) outlet:
Moisture{% Vol.) outlet
Control Device Characteristics
Device Type
Pressure Drop (in W.G.)
Liquor pH (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (%)
Ammonia Emissions"
Ammonia Cone.
(gr/dscf) outlet:
Emission Rate
Ob/hr) outlet:
Emission Factor
{Ib/ton ) outlet:
1
11/9/78
102
14.9
72
26
23,264
25,866
112
3.4
2
11/10/78
102
14.7
66
57
26,106
25,843
112
4.0
3
11/10/78
102
14.6
75
52
30,069
27,062
113
4.9
Ave.
102
14.7
71
45
26,480
26,257
112
4.1
Buffalo Forae Scrubber
3.2
6.3
2.0474
0.0108
408.39
2.4
27.409
0.161
99.4
0.0038
0.84
0.056
6.9
6.6
2.5086
0.0202
561.50
4.47
38.197
0.304
99.2
0.0437
9.68
0.659
6.8
6.0
2.5254
0.0145
651.07
3.37
44.594
0.231
99.5
0.0588
13.64
0.935
5.6
6.3
2.3605
0.0152
540.32
3.41
36.733
0.232
99.4
0.0354
8.05
0.550
Inlet data is based on the combination of the chain mill and precooler data.
Ammonia emissions from the precooler are all negative.
A-59
-------
TABLE A-22. PLANT D: OPACITY READINGS AT THE
BUFFALO FORGE SCRUBBER STACK
TSST SO.
GESZXAL DATA
Oats
Tiae
SIX MTMT7TZ lyrSSVAZ,
AVZ3AGZ OPAC:T!f 1%)
i
2
3
4
5
5
7
3
9
10
11
12
13
14
15
16
17
13
13
20
21
22
23
24
25
2S
27
23
29
30
1
11/10
0947-1047
10
9
10
u
10
10
10
10
10
9
.
-
-
—
—
—
-
—
—
—
—
_
_
_
.
_
_
-
_
-
2
11/10
1130-1430
^i
11
10
10
LO
10
10
11
10
10
11
10
10
^1_
10
10
11 .
10
10
10
10
10
10
10
10
10
10
10
10
10
3
11/10
1430-1530
10
10
11
T_1_
10
10
10
10
10
10
9
11
10
3
9
7.5
3.5
7
S . 5
7
-
-
-
-
-
_
-
-
_
-
A-60
-------
TABLE A-23a. PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE COOLER OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%)
Production Rate (Hg/hr)
Ambient Temp. (K)
(3) Relative Humidity
Exhaust Characteristics
Flowrate
(dnm3/min)
Temperature
(K)
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(gAg) a
Ammonia Emissions
1
11/3/78
96
13.3
302
36
351
351
1.3
0.106
2.227
0.167
.
2
11/4/78
101
12.8
295
49
347
349
1.3
0.205
4.264
0.333
3
11/4/78
101
13.3
302
34
349
352
1.2
0.115
2.400
0.180
Ave.
99
13.2
300
40
350
350
1.3
0.153
3.216
0.246
Ammonia emissions are all negative, more nitrate than ammonia ions present.
A-61
-------
TABLE A-23b.
PLANT D: SUMMARY OF EMISSION TEST RESULTS
AT THE COOLER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate Tons/hr
Ambient Temp. °F
(3) Relative Humidity
Extiaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (% Vol.)
Ammonium Nitrate Emissions
Participate Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions3
1
11/3/78
96
14.7
85
36
12,396
173
1.3
0.0463
4.91
0.334
2
11/4/78
101
14.1
72
49
12,249
168
1.3
0.0897
9.40
0.666
3
11/4/78
101
14.7
84
34
12,348
174
1.2
0.050
5.29
0.360
Ave.
99
14.5
80
40
12,382
171
1.3
0.0669
7.09
0.492
aAnmonia emissions are all negative, more nitrate than aranonia ions present.
A-62
-------
CyM
-------
5
A.5 Plant E
A.5.1 Process Description
Plant E produces ammonium nitrate granules in rotary drum granulators.
This plant has a design production rate of 435 Mg/day (480 TPD) of
ammonium nitrate.
The 85 percent ammonium nitrate solution produced in the neutralizer
is combined with recycled scrubber liquor and the product from cleanup
operations. This combined stream is concentrated to a 99+ percent
ammonium nitrate melt in two steps. First, the AN solution is concentrated
in a flash evaporator, then this product is split and sent through two
parallel air swept falling film evaporators. The melt is then sprayed
into the granulators.
There are two rotary drum granulators; each has its own set of
screens and product cooler. Oversize particles from the screens are
crushed and returned to the granulator. Undersize particles are returned
directly to the granulator. The product size granules are cooled in the
rotary drum coolers with refrigerated air flowing countercurrent to the
granule flow. The cooled granules are then coated and bulk loaded.
A.5.2 Emission Control Equipment
The emission control equipment used at Plant E consists of a condenser
for neutralizer overheads, wet scrubbers for granulators and coolers,
and baghouses to control emissions from coating, handling and shipping
operations. Emissions from the air swept falling film evaporator and
the hammer-mill are directed to the granulator scrubber. Emissions from
the flash evaporator are exhausted to the atmosphere uncontrolled.
Each granulator has two wet scrubbers controlling exhausts, and
each cooler has one scrubber. The exhausts from all the wet scubbers
are ducted to a common stack. The condensate from the neutralizer
overhead is used as scrubber liquor in these wet scrubbers.
The wet scrubbers used are Joy Turbulaire medium pressure drop wet
impingement scrubbers, referred to as "Doyle" units. Air entering the
A-64
-------
scrubbers enters a cone-shaped downcomer, causing it to impinge on a
liquor pool. Scrubber liquor is sprayed on the entering airstream in
each downcomer. The exhaust then passes over and under a set of baffles
and exits the scrubber.
A.5.3 Facilities Tested
Only one source was tested at Plant E, the No. 1 cooler scrubber.
The inlet and outlet of this scrubber were tested for ammonium nitrate
particulate and ammonia emissions. The scrubber inlet was also tested
to determine particle size with an Anderson Cascade Impactor. The
results of the emission tests are presented in Tables A-24a and A-24b,
and the particle size results are presented in Figure A-8.
A.5.3.1 Testing Problems
Most of the test runs were discontinuous due to excessive particulate
loading at the scrubber inlet sampling location. Data from test 3 are
believed to be nontypical of the sampled source, and are not represented
in the average data. The ammonium nitrate concentration at the scrubber
outlet was found to be greater than the concentration at the inlet
during test 3. During train clean-up a residue was noted on the inside
of the probe. This residue was not present in tests 1 and 2.
A.5.4 Process Operation During Testing
The process was operating at 62 to 66 percent of design capacity
during the testing. No major irregularities in process operation were
noted during testing, although the cooler outlet air temperature and the
cooler inlet and outlet solids temperature varied considerably during
the individual test periods.
A-65
-------
TABLE A-24a.
PLANT E: SUMMARY OF EMISSION TEST RESULTS
FOR THE COOLER SCRUBBER (METRIC)
Test No.
General Data
Date
Isokinetic (%) In/Out
Production Rate (Mg/hr)
Ambient Temp. (K)
(%) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dnm^/min) outlet:
Temperature inlet:
(K) outlet:
MoistureC*. Vol.) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (kPa)
Liquor pH (Ave.)
Liquor Cone. (%} Ave.
Ammonium Nitrate Emissions
Particulate Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission factor inlet:
(g/kg) outlet:
Collection Efficiency (%)
Ammonia Emissions
Ammonia Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet
(g/kg) outlet:
Collection Efficiency (%)
1
11/15/78
109/106
11.52
279
62
428
438
325
307
1.1
3.4
Doyle
3.28
3.7
23
3.86
0.014
99.17
0.38
8.65
0.033
99.6
0.5526
0.0080
14.20
0.209
1.235
0.018
98.5
2
11/15/78
105/105
11.26
281
54
397
455
329
308
1.5
3.5
wet impingement
3.28
4.5
26
4.09
0.135
97.55
0.37
8.65
0.33
99.5
0.5279
0.0066
12.57
0.181
1.115
0.016
98.6
3
* 11/16/78
102/104
11.86
278
69
424
483
319
308
0.7
3.1
scrubber
3.23
4.3
26
0.441
2.14
11.23
62.10
0.945
5.25
Negative
1.3481
0.0373
34.25
1.08
2. 38
0.091
96.8
Ave.
*
105/106
11.38
279
62
413
459
327
307
1.3
3.5
3.27
4.2
25
3.98
0.014
98.36
0.38
8.65
0.033
99.6
0.5402
0.0073
13.38
0.195
1.175
0.017
98.6
•Run jQuestionaoTe, not used in average.
A-66
-------
TABLE A-24b.
PLANT E: SUMMARY OF EMISSION TEST RESULTS
FOR THE COOLER SCRUBBER (ENGLISH)
Test No.
General Data
Date
Isokinetic (*«} In/Out
Production Rate Tons/hr
Ambient Temp. °F
(Z) Relative Humidity
Exhaust Characteristics
Flowrate inlet:
(dscfm) outlet:
Temperature inlet:
(F°) outlet:
Moisture (% Vol.) inlet:
outlet:
Control Device Characteristics
Device Type
Pressure Drop (in. W.S. )
Liquor pH (Ave.)
Liquor AN Cone. (%) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
Ob/ton) outlet:
Collection Efficiency (£)
Ammonia Emissions
Ammonia Cone. inlet:
(gr/dscf) outlet:
Emission Rate inlet
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency
1
11/15/78
104/106
12.69
43
62
15,111 14
15,471 16
125
94
1.1
3.4
Doyle
13.2
3.7
23
1.688
0.0063
218.6
0.835
17.3
0.066
99.6
0.2413
0.0035
31.3
0.461
2.47
0.636
98.5
2
11/15/78 *
105/105
12.41
46
54
,018 14
,065 17
133
95
1.5
3.5
wet impingement
13.2
4.5
26
1.790
0.0059
215.0
0.816
17.3
0.066
99.6
0.2305
0.0029
27.7
0.399
2.23
0.032
98.6
3
11/16/78
102/104
13.07
41
69
,968
,044
115
95
0.7
3.1
scrubber
13.0
4.3
26
0.1929
0.9371
24.74
136.9
1.89
10.5
0.5887
0.0163
75.5
2.38
5.76
0.182
96.8
Ave.
*
104/105
12.54
43
62
14,600
15,768
129
94
1.3
3.5
13.1
4.2
25
1.739
0.0061
216.8
0.826
17.3
0.066
99.6
0.2359
0.0032
29.5
0.430
2.35
0.034
98.6
"Run 3 Questionable, not used in average.
A-67
-------
»„
«» JQ a a 10 a t i oa « a.i o.o» aoi
ioao
sou
3.1 _
zaa
to
PASTICLS SIZZ DISTSI3QTION
is i i 2 ) :a a 9 *o •» -a xt u TO <* '•» » ».» »»
CUMULATIVE PES CENT 3T WEJ5HT LESS THA.N(OP|
Figure A-8. Plant E: Particle size results at the cooler scrubber inlet.
A-68
-------
6
A.6 Plant Z
A.6.1 Process Description
Plant Z produces both low density and high density ammonium nitrate
prills. The plant was designed to produce 726 Mg/day (800 TPD) of
prilled ammonium nitrate. Only the emissions from the solids formation
and finishing equipment were monitored; therefore, only these solids
production facilities are discussed.
The prill tower at Plant Z is designed to produce both high and low
density prills. The type of product produced depends upon the concentration
of the AN melt used. A 99.8 percent AN melt is used to produce high
density prills, and a 96 percent AN melt is used to produce low density
prills.
During the testing program low density prills were being produced.
For low density prill production, a 96 percent AN melt is delivered from
the evaporators to the top of the prill tower. A spinning bucket at the
top of the tower receives the melt, where it rotates to force a stream
of melt through orifices in the bucket. The melt stream breaks up into
discrete droplets as it falls through the tower. Four fans located at
the top of the prill tower create an airflow which cools the falling
droplets. The prills are conveyed from the bottom of the tower to the
finishing train, the predryer, dryer and cooler. First, the low density
prills are conveyed to a rotary drum predryer, where moisture is removed
from the prills. Finally, a fluidized bed cooler is used to remove
nominal amounts of moisture and to cool the prills. Cooled prills are
then screened to yield a properly sized product.
Offsize prills are redissolved and recycled to the melt concentration
process. Product sized prills are coated in a rotary drum coater with
kaolin (clay). A coating is used to prevent the solids from becoming
moist and caking. The coated product is then either bulk shipped or
bagged.
A-69
-------
A.6.2 Emission Control Equipment
The equipment used to control emissions from the prill tower,
predryer, dryer, cooler, screens, coater and bagger are discussed below.
Emissions from the prill tower are controlled with a collection
device and a Monsanto HE Brinks Mist Eliminator which is located on top
of the tower. The tower is equipped with four fans; three of which are
located at the top of the tower along the periphery (bypass). The other
fan is located at the top of the tower after the mist eliminator, with
inlets located within the collection device. The stainless steel collection
device is located around the spinning bucket. Since most of the fuming
and ammonium nitrate emissions occur as the melt exits the bucket, the
collection device captures a large portion of the emissions and ducts
this portion to the mist eliminator. The air that does not get ducted
to the mist eliminator is discharged through the three bypass stacks.
The Brinks Mist Eliminator contains atomizing sprays and spray
catcher elements to remove large particulates and high efficiency elements
to remove fine particulates. The liquor for the sprays comes from the
evaporator condensate. The liquor is pH adjusted, using nitric acid to
maintain the pH near neutral; otherwise, the fiberglass filter elements
would corrode. The liquor is recycled through the Brinks until it
reaches an AN concentration near 5 percent. The liquor is then recycled
to the AN solution formation process.
Emissions from the rotary drum predryer and dryer are combined and
ducted to a single Peabody tray scrubber. The fluidized bed cooler uses
two inlet air streams to cool the prills. One of these air streams is
discharged to a Ducon mechanical impingement scrubber, and the other
stream is discharged, uncontrolled, through a vent.
Emissions from the screening operation are ducted to a baghouse
fabric filter. Rotary drum coater emissions are also controlled by a
baghouse. The clay dust captured by the fabric filter is returned to
the clay storage bins for reuse in the coater. Emissions from bagging
operations are controlled by fabric filters, too. Captured dust is also
returned to the clay storage bins.
A-70
-------
A.6.3 Facilities Tested
The facilities tested at Plant Z are listed below:
Low density prill tower scrubber inlet, outlet and bypass
Rotary drum predryer outlet
Rotary drum dryer outlet
Combined predryer-dryer scrubber outlet
Fluidized bed cooler scrubber inlet
Bagging and coating operations
Visible emission observations were performed at all of the scrubber
outlets and at the outlets from the coater and bagger. Particle size
measurements were performed at all of the scrubber inlets and bypasses.
An Anderson High Capacity Stack Sampler was used to determine particle
size distributions. A discussion of the testing at each facility including
any testing problems that occurred, follows.
A.6.3.1 Low Density Prill Tower Scrubber
The results of the mass emission tests performed on the bypass and
the Brinks Mist Eliminator inlet and outlet are presented in Tables
A-25a and A-25b. Prill tower emissions are ducted to the Brinks Mist
Eliminator through three inlet ducts. Three ducts are also used to
bypass the mist eliminator. During each test run, emissions were measured
at one inlet, one bypass and the outlet. Velocity traverses were performed
at the other two inlets and two bypasses during each test run in order
to determine flow rates through these ducts. Estimates of emissions
from all the inlets and bypasses during each test run were made by
assuming the grain loadings measured in a given inlet or bypass existed
in the other two inlets or bypasses.
The opacity readings at the Brinks Mist Eliminator outlet are
presented in Table A-26; opacity readings for the scrubber bypass are
presented in Table A-27. Particle size results at the scrubber inlet
are presented in Figure A-9, particle sizes results for the bypass are
presented in Figure A-10. No problems were encountered during testing
at this scrubber.
A-71
-------
A.6.3.2 Rotary Drum Predryer Outlet
Results of the mass emission tests performed at the predryer outlet
are presented in Tables A-28a and A-28b. The results of the particle
size tests are presented in Figure A-ll.
High grain loadings at this point caused immediate nozzle and pitot
tube plugging when the tests were begun. Larger diameter nozzles were
then attached to the probes and plugging problems were greatly reduced.
However, the sampling train pumps were unable to draw a sufficient flow
through these larger nozzles to maintain isokinetic sampling conditions.
To compensate for isokinetic sampling percentages less than 90 percent,
a second method, the area ratio method, was also used to calculate mass
flow rates. An average of flow rates determined by the concentration
method and the area ratio method were used in these cases.
A.6.3.3 Rotary Drum Dryer Outlet
The dryer outlet mass emissions results are presented in Tables A-29a
and A-29b. Particle size results are presented in Figure A-12.
Nozzle plugging and isokinetic sampling problems which occurred at
the predryer outlet were also encountered at the dryer outlet. In
addition to this, negative ammonia emissions were determined during Test
No. 1 at this outlet. This result is probably a reflection of the low
excess ammonia present in the dryer and of the inaccuracies inherent in
the ammonia analysis method.
A.6.3.4 Combined Predryer-Dryer Scrubber
Tables A-30a and A-30b present the results of the mass emission
tests performed at this scrubber. The scrubber inlet results presented
were determined fay weighing the emissions from the predryer and dryer by
flow rate. The results of the visible emission observations are presented
in Table A-31. No problems were encountered during tests on the scrubber
outlet.
A.6.3.5 Fluidized Bed Cooler Scrubber
Results of the mass emission tests performed at the cooler scrubber
inlet and bypass are shown in Tables A-32a and A-32b.
A-72
-------
Particle size results for the scrubber inlet and bypass are presented in
Figures A-13 and A-14, respectively. Visible emissions observations,
performed at the scrubber outlet and bypass, are presented in Tables A-33
and A-34, respectively.
No problems were encountered during testing at the fluidized bed
cooler scrubber, although ammonia emissions during some of the tests
were negative. This was probably due to inaccuracies inherent in the
ammonia analyses and in the excess ammonia calculation.
A.6.3.5 Coater and Bagger
Visible emission observations were performed at the outlets from
the coating and bagging fabric filters. These opacity readings are
presented in Table A-35.
A.6.4 Process Operation During Testing
The process was operating at 56 to 80 percent of design capacity
during testing. Production rates reflect market demands.
A review of the operating logs during testing revealed that there
were no anomalies in process operation during the test period that
affected emissions. Slight variations in operations which occurred were
all within normal operative conditions.
A few minor problems occurred and are detailed below. At 9:00 a.m.
on August 13, 1980, there was a ten minute decrease in production due to
steam loss in the evaporator. On August 14, 1980 the system was down at
8:00 a.m., but returned to normal operation at 9:30 a.m. Also, on
August 14, 1980 at 1:30 p.m. ammonium nitrate production was cut back
five percent.
A-73
-------
TABLE A-25a.
PLANT Z: SUMMARY OF EMISSION TEST RESULTS FOF
PRILL TOWER INLET, OUTLET AND BYPASS (METRIC)0
THE
Test No.
Ave.
General Data
Date
Isokinetic (I) In/Out/Bypass
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidtiy (S)
Exhaust Characteristics
Flowrate (dnm3/nin)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Temperature (K)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Moisture (* Vol.)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Control Device Characteristics
Device Type
Pressure Drop (kPa)
Liquor pH (Ave.}
Liquor AN Cone, (ppra) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, (gr/dnm }
scrubber inlet:
scrubber outlet:
scrubber bypass:
Emission Rate (kg/hr)
scrubber inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Emission Factor (g/kg)
scrubber inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Collection Efficiency (S)
scrubber:
total:
Ammonia Emissions
Ammonia Cone, (gr/dnn }
scrubber inlet:
scrubber outlet:
scrubber bypass:
Emission Rate (kg/hr)
scrubber inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Emission Factor (g/kg)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Total bypass and outlet:
Collection Efficiency (1}
scrubber:
total:
8/12/80
99.5/105.7/98.4
21.1
305
55
1277
1447
6579
325
307
315
2.82
6.66
1.99
8/12/80
100.7/103.7/98.1
22.2
308
45
1269
1497
69 58
326
307
319
2.94
3.38
2.35
Brinks M1st Eliminator
3.4 3.5
4.06 5.36
73.4 76.6
0.0364
0.00371
0.0104
2.79
0.321
4.11
4.43
0.132
0.015
0.195
0.210
88.5
35.3
0.0344
0.0120
0.0016
2.632
1.043
0.631
1.674
0.125
0.050
0.030
0.080
60.2
51.5
0.0524
0.00336
0.0130
3.99
0.303
5.41
5.71
0.180
0.014
0.244
0.257
92.4
39.2
0.0302
0.0105
0.0015
2.302
0.943
0.631
1.574
0.101
0.043
0.029
0.071
57.7
55.0
8/13/80
100.5/99.2/103.3
23.1
302
68
1308
1468
5983
322
307
313
3.28
4.35
3.02
3.4
3.87
71.8
0.0547
0.00796
0.0152
4.29
0.703
5.47
6.17
0.186
0.031
0.237
0.267
83.6
36.3
0.0236
0.0116
0.0015
1.851
1.025
0.526
1.551
0.080
0.045
0.023
0.067
44.4
65.4
100.4/102.9/99.9
22.1
305
56
1285
1471
6507
325
307
316
3.01
4.80
2.44
3.4
4.43
73.9
0.0478
0.00501
0.0129
3.69
0.442
5.00
5.44
0.167
0.020
0.226
0.246
88.0
37.4
0.0293
0.0114
0.0015
2.259
007
599
606
0.102
0.046
0.027
0.073
55.4
56.2
The inlet and bypass results xere obtained by weighing the individual results at each of the three sampling points.
Pounds per hour values were calculated by assuming that the grain loadings measured at one point existed it the
other two points, and then nultiplying by the total flowrate.
A-74
-------
TABLE A-25b. PLANT Z: SUMMARY OF EMISSION TEST RESULTS FOR THE
PRILL TOWER SCBUBBER INLET, OUTLET AND BYPASS (ENGLISH)'
Test No.
General Data
Date
Isokinetic (5) In/Out/Bypass
Production Rate tons/hr
Ambient Temp. °F
Relative Humidity (S)
Exhaust Characteristics
Flowrate (dscfm)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Temperature (°F)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Moisture (*. Vol.)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Control Device Characteristics
Device Type
Pressure Drop (in. W.S.)
Liquor pH (Ave. )
Liquor AN Cone, (ppm) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone, (gr/dscf)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Emission Rate (Ib/hr)
scrubber Inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Emission Factor (Ib/ton)
scrubber inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Collection Efficiency (I)
scrubber:
total:
Atmonia Emissions
Ammonia Cone, (gr/dscf)
scrubber inlet:
scrubber outlet:
scrubber bypass:
Emission Rate (Ib/hr)
scrubber inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Emission Factor (Ib/ton)
scrubber inlet:
scrubber outlet:
scrubber bypass:
total bypass and outlet:
Collection Efficiency (?)
scrubber:
total :
1
8/12/80
99.9/105.7/98.4 100
23.3
90
55
45,130
51,120
232,460
126
94
107
2.82
6.66
1.99
Brinks Mist Eliminator
13.7
4.06
73.4
0.0159
0.00162
0.00455
6.150
0.708
9.066
9.774
0.264
0.030
0.389
0.419
88.5
35.8
0.0150
0.00526
0.00070
5.802
2.30
1.39
3.69
0.249
0.099
0.060
0.159
60.2
51.5
2
8/12/80
.7/103.7/98.1
24.5
95
45
44,850
52,910
245,870
128
93
115
2.94
3.38
2.35
14.2
5.36
76.6
0.0229
0.00147
0.00566
8.803
0.667
11.928
12.595
0.359
0.027
0.487
0.514
92.4
39.2
0.0132
0.00459
0.00066
5.074
2.08
1.39
3.47
0.201
0.085
0.057
0.142
57.7
55.0
3
8/13/80
100.5/99.2/103.3
25.5
35
68
46,220
51,870
211,417
120
94
104
3.28
4.35
3.02
13.6 -
3.87
71.8
0.0239
0.00348
0.00665
9.468
1.549
12.051
13.600
0.371
0.061
0.473
0.534
83.6
36.8
0.0103
0.00508
0. 00064
4.081
2.26
1.16
3.42
0.160
0.089
0.045
0.134
44.4
65.4
Ave.
100.4/102.9/99.9
24.4
90
56
45,400
51,970
229,920
125
94
109
3.01
4.80
2.44
13.8
4.43
73.9
0.0209
0.00219
0.00562
3.133
0.975
11.015
11.990
0.333
0.040
0.451
0.491
88.0
37.4
0.0128
0. 00498
0. 00067
4.981
2.22
1.32
3.54
0.204
0.091
0.054
0.145
55.4
56.2
The inlet and bypass results *ere obtained by weighing the individual results at each of the three sampling points.
Pounds per hour values were calculated by assuming that the grain loadings measured at one point existed at the other
two points, and then multiplying by the total flowrate.
A-75
-------
TABLE A-26. PLANT Z: OPACITY READINGS AT THE PRILL TWER SCRUBBER OUTLET
Date
8-12-80
Run
Number
*-j
Ch
8-12-80
Six-Minute
Time Period
1046 - 1051
1052 - 1057
1058 - 1103
1104 - 1109
1110 - 1115
1116 - 1121
1122 - 1127
1128 - 1133
1134 - 1139
1140 - 1145
1147 - 1152
1153 - 1158
1159 - 1204
1205 - 1210
1211 - 1216
1217 - 1222
1223 - 1228
1229 - 1234
1235 - 1240
1241 - 1246
Average
1520 - 1525
1526 - 1531
1532 - 1537
1538 - 1543
1544 - 1549
1550 - 1555
1556 - 1601
1602 - 1607
1608 - 1613
1614 - 1619
1620 - 1625
1626 - 1631
1632 - 1637
1638 - 1643
1644 - 1649
1650 - 1655
1656 - 1701
1702 - 1707
1708 - 1713
1714 - 1719
Average
Average Opacity Run Six-Minute
(Percent) Date Number Time Period
0 8-13-80 3 0845 - 0850
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0851 - 0856
0857 - 0902
0903 - 0908
0909 - 0914
0915 - 0920
0921 - 0926
0927 - 0932
0933 - 0938
0939 - 0944
0945 - 0950
0951 - 0956
0957 - 1002
1003 - 1008
1009 - 1014
1015 - 1020
1021 - 1026
1027 - 1032
1033 - 1038
1039 - 1044
1045 - 1050
1051 - 1056
1255 - 1300
1301 - 1306
1307 - 1312
1313 - 1318
1319 - 1324
1325 - 1330
1331 - 1336
1337 - 1342
1343 - 1348
1349 - 1354
1355 - 1400
1401 - 1406
1407 - 1412
1413 - 1418
1419 - 1424
1425 - 1430
1431 - 1436
1437 - 1442
1443 - 1448
1449 - 1454
Average
Average Opacity
(Percent)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
TABLE A-27. PLANT Z: OPACITY READINGS AT THE PRILL TOWER SCRUBBER BYPASS
R
l.ora t Ion Date Nu
Bypass B B-12-80
'ypass A I
un Six-Minute
mber Tln»> Period
1 1049 - 1054
1055 - 1100
1101 - 1106
1107 - 11)2
1113 - 1118
1119 - 1124
1125 - 1130
1131 - 1136
1137 - 1142
1143 - 1148
1149 - 1154
1155 - 1201
1202 - 1206
1207 - 1212
1213 - 1218
1219 - 1224
1225 - 1230
1231 - 1236
1237 - 1242
1243 - 1248
Average
1520 - 1525
1526 - 1531
1532 - 1537
1538 - 1543
1544 - 1549
1550 - 1555
1556 - 1501
1602 - 1607
1608 - 1613
1614 - 1619
1620 - 1625
1626 - 1631
1632 - 1637
1638 - 1643
1644 - 1649
1650 - 1655
1656 - 1701
1702.- 1707
1708 - 1713
1714 - 1719
Average
Average Opacity
Lfer.-eiiti
7.7
7.5
7.1
5.6
7.1
4.8
5.8
6.9
6.3
.3
.1
.3
.0
.5
.3
.2
5.4
6.7
6.9
5.6
6.4
8.3
7.3
7.5
6.7
.5
.3
.5
.2
.6
5.4
6.3
7.5
6.0
5.6
5
5
5
5
5
5
6.0
Location
Bypass C
Run SIx-MlmHe
Da ^e__ Number Tine Period
B-U-80 3 0952 - 0957
0958 - 100)
1004 - 1009
1010 - 1015
1016 - 1021
1022 - 1027
1028 - 1013
1014 - 1039
1040 - 1045
104C - 1051
1052 - 1057
1058 - 1103
1104 - 1109
1110 - 1115
111S - 1121
1122 - 1119
1120 - 1133
1134 - 1139
1140 - 1145
1146 - 1151
Average
Average Opacity
IPercen tj
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
. 0
0
-------
TABLE A-28a. PLANT Z: SUMMARY OF EMISSION TEST RESULTS
FOR THE PREDRYER OUTLET (METRIC)
Test No.
General Data
Date
Isokinetic (%)
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidity (%)
Exhaust Characteristics
Flowrate
(dnm3/min)
Temperature
(K)
Moisture (I Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(g/dnm3)
Emission Rate*
(kg/hr)
Emission Factor
(9/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm3)
Emission Rate*
(kg/hr)
Emission Factor
(g/kg)
1
8/14/80
83.9
20.0
306
56
1088
339
4.8
10.63
637
31.91
0.0321
2.53
0.127
2
8/14/80
93.4
19.9
308
46
1095
339
3.6
11.31
744
39.21
0.1443
9.48
0.50
3
8/14/80
93.1
18.5
306
54
1096
339
3.5
11.57
761
21.11
0.0616
4.15
0.224
Ave.
90.1
19.5
307
52
1093
339
4.0
11.18
714
37.28
0.0772
5.40
0.292
*For runs with percent isokinetic less than 90%, mass flowrates (kg/hr) presented here are
averages of mass flowrates calculated by concentration method and area ratio method.
A-78
-------
TABLE A-28b. SUMMARY OF EMISSION TEST RESULTS
FOR THE PREDRYER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate tons/hr
Ambient Temp. °F
Relative Humidity (%)
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(gr/dscf)
Emission Rate*
(Ib/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate*
(Ib/hr)
Emission Factor
(Ib/ton)
1
8/14/80
83.9
22.0
92
56
38440
151
4.8
4.64
1404
63.82
0.0140
5.58
0.254
2
8/14/80
93.4
20.9
95
46
38680
151
3.6
4.94
1639
78.42
0.06303
20.9
1.00
3
8/14/80
93.1
20.4
92
54
38720
151
3.5
5.05
1677
42.21
0.0269
9.14
0.448
Ave.
90.1
21.1
93
52
38610
151
4.0
4.88
1573
74.55
0.0337
11.9 '
0.583
*For runs with percent isokinetic less than 90% mass flowrates (Ib/hr) presented here
averages of mass flowrates calculated by concentration method and area ratio method.
are
A-79
-------
TABLE A-29a. PLANT Z: SUMMARY OF EMISSION TEST RESULTS
FOR THE DRYER OUTLET (METRIC)
Test No.
Genera] Data
Date -
Isoklnetic (X)
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidity (X)
Exhaust Characteristics
Flowrate
(dnm3/min)
Temperature
(K)
Moisture (% Vol.)
Ammonium Nitrate Emissions
Particulate Cone.
(g/dnm3)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
Ammonia Emissions
Ammonia Cone.
(g/dnm)
Emission Rate
(kg/hr)
Emission Factor
(g/kg)
1
8/14/80
83.3
20.0
306
56
955
336
5.2
29.54
1552
77.75
Negative
2
8/14/80
84.9
19.9
308
46
988
334
4.5
36.87
2016
106.32
0.2725
14.06
0.742
3
8/14/80
83.0
18.5
306
54
962
335
4.4
34.58
1814
97.99
1.079
57.61
3.113
Ave.
83.7
19.5
307
52
967
335
4.7
33.66
1794
93.70
0.449b
24.36
u
1.300°
aFor runs with isokinetic percent less than 90% mass flowrates (kg/hr) presented here
are averages of mass flowrates calculated by concentration method and area ratio method.
The average was calculated by assuming Run 1 values are zero.
A-80
-------
TABLE A-29b. PLANT Z: SUMMARY OF EMISSION TEST RESULTS
FOR THE DRYER OUTLET (ENGLISH)
Test No.
General Data
Date
Isokinetic (%)
Production Rate tons/hr
Ambient Temp. °F
Relative Humidity (%)
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
(8F)
Moisture (* Vol.)
Ammonium Nitrate Emissions
Part icul ate Cone.
(gr/dscf)
Emission Rate
Ob/hr)
Emission Factor
(Ib/ton)
Ammonia Emissions
Ammonia Cone.
(gr/dscf)
Emission Rate
Ob/hr)
Emission Factor
(Ib/ton)
1
8/14/80
83.3
22.0
92
56
33,750
146
5.2
12.9
3421
155.5
Negative
2
8/14/80
84.9
20.9
95
46
34,900
142
4.5
16.1
4444
212.63
0.119
31.0
1.483
3
8/14/80
83.0
20.4
92
54
33,890
144
4.4
15.1
3998
195.98
0.471
127.0
6.225
Ave.
83.7
21.10
93
52
34,180
144
4.7
14.7
3954
187.39
0.196b
53.70b
u
2.600°
aFor runs with isokinetic percent less than 90% mass flowrates (Ib/ton) presented here are
averages of mass flowrates calculated by concentration method and area ratio method.
The average was calculated by assuming Run 1 values are zero.
A-81
-------
TABLE A-30a.
PLANT Z: SUMMARY OF EMISSION TEST RESULTS FOR THE
COMBINED PREDRYER AND DRYER SCRUBBER (METRIC)9
Test No.
General Data
Date
Isok-inetic («)
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidity (%)
1
8/14/80
83.6/102.3
20.0
306
56
2
8/14/80
89.2/101.3
19.9
308
46
3
8/14/80
88.1/100.8
18.5
306
54
Ave.
87.0/101.5
19.5
307
52
Exhaust Characteristics
Flowrate inlet:
(dnm^/min) outlet:
Temperature inlet:
(K) outlet:
Moisture (% Vol.) inlet:
outlet:
Control Device Characteristics
Device Type
Liquor pH (Ave.)
Liquor AN Cone, (ppm) (Ave.)
Ammonium Nitrate Emissions
Particulate Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (%)
Ammonia Emissions
Ammonia Cone. inlet:
(g/dnm3) outlet:
Emission Rate inlet:
(kg/hr) outlet:
Emission Factor inlet:
(g/kg) outlet:
Collection Efficiency (2)
2044
2089
338
315
5.0
4.6
Peabody Tray
6.29
570
19.4
0.0991
2189
12.4
109.66
0.623
99.4
0.0321b
0.0698u
2.531b
8.755.
0.127°
0.439
Negative
2084
2070
337
315
4.0
4.8
Scrubber
6.47
645
23.3
0.0936
2759
11.6
145.53
0.613
99.6
0.2052
0.1074
11.653
13.381
0.6145
0.7055
Negative
2056
2071
337
316
3.9
4.1
6.33
677
22.3
0.107
2574
13.3
139.10
0.718
99.5
0.5439
0.0669
29.502
8.301
1.594
0.4485
97.2
2061
2077
337
315
4.3
4.5
6,36
631
21.7
0.0999
2507
12.4
131.00
0.6145
99.5
0.2604
0.0813
14.561
10.161
0.7785
0.531
31.8
The inlet values are weighted by the predryer and dryer flowrates.
Includes only the inlet predryer concentration, the dryer ammonia emissions
were negative.
A-82
-------
TABLE A-30b.
PLANT Z: SUMMARY OF EMISSION TEST RESULTS FOR THE
COMBINED PREDRYER AND DRYER SCRUBBER (ENGLISH)3
Test No.
Ave.
General Data
Date
Isokinetlc (%) In/Out
Production Rate tons/hr
Ambient Temp. °F
Relative Humidity (£)
Exhaust Characteristics
Flowrate
(dscfm)
Temperature
(°n
Moisture (% Vol.)
inlet:
outlet:
inlet:
outlet:
inlet:
outlet:
Control Device Characteristics
Device Type
Liquor pH (Ave.)
Liquor AN Cone, (ppm)
Ammonium Nitrate Emissions
Particulate Cone. inlet:
(gr/dscf) outlet:
Emission Rate inlet:
(Ib/hr) outlet:
Emission Factor inlet:
(Ib/ton) outlet:
Collection Efficiency (%)
Arnmonia Emissions
8/14/80
83.6/102.3
22.0
92
56
72,190
73,770
149
108
5.0
4.6
8/14/80
89.2/101.3
20.9
95
46
73,580
73,100
147
108
4.0
4.8
Peabody Tray Scrubber
6.29 6.47
570 645
8.50
0.0433
4825
27.4
219.32
1.245
99.4
10.2
0.0409
6083
25.6
291.05
1.225
99.6
8/14/80
88.1/100.8
20.4
92
54
72,610
73,120
148
110
3.9
4.1
6.33
677
9.74
0.0467
5675
29.3
278.19
1.436
99.5
87.0/101.5
21.1
93
52
72,790
73,330
148
109
4.3
4.5
6.36
631
9.48
0.0436
5528
27.4
261.99
1.299
99.5
Ammonia Cone.
(gr/dscf)
Emission Rate
(Ib/hr)
Emission Factor
(Ib/ton)
inlet:
outlet:
inlet:
outlet:
inlet:
outlet:
Collection Efficiency
0.0140b
0.0305.
5.58°
19.3.
0.254°
0.877
Negative
0.0896
0.0469
25.69
29.5
1.229
1.411
Negative
0.2375
0.0292
65.04
18.3
3.188
0.897
97.2
0.1137
0.0355
32.10
22.4
1.557
1.062
31.8
aThe inlet values are weighted by the predryer and dryer flowrates.
Includes only the inlet predryer concentration, the dryer ammonia emissions were negative.
A-83
-------
TABLE A-31. PLANT Z: OPACITY READINGS AT THE COMBINED PREDRYER-DRYER SCRUBBER OUTLET
>
00
Run Six-Minute
Date Number Time Period
8-14-80 1 1105 - 1110
'
1111 - 1116
1117 - 1122
1123 - 1128
1129 - 1134
1135 - 1140
1141 - 1146
1147 - 1152
1153 - 1158
1159 - 1204
1205 - 1210
1211 - 1216
1217 - 1222
1223 - 1228
1229 - 1234
1235 - 1240
1241 - 1246
1247 - 1252
1253 - 1258
1259 - 1304
Average
0-14-80 2 1510 - 1515
1516 - 1521
1522 - 1527
1528 - 1533
1534 - 1539
1540 - 1545
1546 - 1551
1552 - 1557
1558 - 1603
1604 - 1609
1610 - 1615
1616 - 1621
1622 - 1627
1628 - 1633
1634 - 1639
1640 - 1645
1646 - 1651
1652 - 1657
1658 - 1703
1704 - 1709
Average
Average Opacity Run Six-Minute
(Percent) Date Number Time Period
0 8-14-80 3 1710 - 1715
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1716 - 1721
1722 - 1727
1728 - 1733
1734 - 1739
1740 - 1745
1746 - 1751
1752 - 1757
1758 - 1803
1804 - 1809
1810 - 1815
1816 - 1821
1822 - 1827
1828 - 1833
1834 - 1839
1840 - 1845
1846 - 1851
1852 - 1857
1858 - 1903
1904 - 1909
0 Average
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Average Opacity
, (Percenjj
0.6
2.3
3.1
1.5
0.8
1.5
0
0.2
0.6
0.2
0
0
0
0
0
0
0
0
0
0
0.5
-------
TABLE A-32a.
PLANT Z: SUMMARY OF EMISSION TEST RESULTS FOR THE
COOLER SCRUBBER INLET AND BYPASS (METRIC)
Test No.
General Data
Date
Isokinetic (X) In/Bypass
Production Rate (Mg/hr)
Ambient Temp. (K)
Relative Humidity (%)
Exhaust Characteristics
Flowrate inlet:
(dnm3/min) bypass:
Temperature inlet:
(K) bypass:
Moisture (% Vol.) inlet:
bypass:
Ammonium Nitrate Emissions
Particulate Cone. inlet:
(g/dnm3) bypass:
Emission Rate inlet:
(kg/hr) bypass:
Emission Factor inlet:
(g/kg) bypass:
total :
Ammonia Emissions
Ammonia Cone. Inlet:
(g/dnm3) bypass:
Emission Rate inlet:
(kg/hr) bypass:
Emission Factor inlet:
(g/kg) bypass:
total :
1
8/15/80
99.7/101.5
19.1
304
67
1160
569
325
318
3.18
2.63
12.89
0.175
896
5.99
47.02
0.315
47.33
0.2405
0.0027
16.78
0.0939
0.881
0.005
0.886
2
8/15/80
100.4/102.2
18.5
305
62
1145
540
327
319
3.20
2.58
8.885
0.232
610
7.48
32.94
0.405
33.35
Negative
0.0013
Negative
0.0422
Negative
0.0025
"
3
8/16/80
100.6/103.2
20.3
301
77
1142
543
326
319
3.67
2.75
9.755
0.186
668
6.08
32.86
0.299
33.16
Negative
Negative
Ave.
100.2/102.3
304
69
1149
551
326
319
3.35
2.65
10.51
0.1857
724
6.12
37.54
0.318
37.85
0.0802
0.0014
- 5.58
0.045
0.294
0.0025
0.296
*Averages calculated by assuming that the negative numbers are zero.
A-85
-------
TABLE A-32b.
PLANT Z: SUMMARY OF EMISSION TEST RESULTS FOR THE
COOLER SCRUBBER INLET AND BYPASS (ENGLISH)
Test No.
General Data
Date
Isokinetic (5) In/Bypass
Production Rate tons/hr
Ambient Temp. °F
Relative Humidity (Z)
Exhaust Characteristics
Flowrate inlet:
(dscfm) bypass:
Temperature inlet:
(°F) bypass
Moisture (% Vol. inlet
bypass
Ammonium Nitrate Emissions
Particulate Cone. inlet:
(gr/dscf) bypass:
Emission Rate Inlet:
(lb/hr) bypass:
Emission Factor inlet:
(Ib/ton) bypass:
total:
Ammonia Emissions
Ammonia Cone. Inlet:
(gr/dscf) bypass:
Emission Rate inlet:
(Ib/hr) bypass:
Emission Factor inlet:
(Ib/ton) bypass:
total :
1
8/15/80
99.7/101.5
21.0
88
57
40,970
20,120
126
113
3.18
2.63
5.63
0.0754
1975 ,
13.2
94.048
0.629
94.667
0.105
0.0012
37.0
0.207
1.762
0.010
1.772
2
8/15/80
100.4/102.2
20.4
90
62
40,450
19,070
129
114
3.20
2.58
3.88
0.1011
1344
16.5
65.882
0.809
66.691
Negative
0.00057
Negative
0.093
Negative
0.005
~
3
8/16/80
100.6/103.2
22.4
83
77
40,350
19,190
127
115
3.67
2.75
4.26
0.0813
1472
13.4
65.714
0.598
66.312
Negative
Negative
Ave.
100.2/102.3
21.3
87
69
40,590
19,460
127
114
3.35
2.65
4.59
0.0811
1596
13.5
75.07
0.635
75.705
0.035*
0.00059
12.3
0.100
0.587
0.005
0.592
^Averages calculated by assuming that the negative numbers are zero.
A-86
-------
TABLE A-33. PLANT Z: OPACITY READINGS AT THE FLUIDIZED BED SCRUBBER OUTLET
Run*
Number
i»
en
8-15-80
Six-Minute
Time Period
1450 - 1455
1456 - 1501
1502 - 1507
1508 - 1513
1514 - 1519
1520 - 1525
1526 - 1531
1532 - 1537
1538 - 1543
1544 - 1549
1550 - 1555
1556 - 1501
1602 - 1607
1608 - 1613
1614 - 1619
1620 - 1625
1626 - 1631
1632 - 1637
1638 - 1643
1644 - 1649
Average
1100
1106
1112
1118
1124
1130
1136
1142
1148
1154
1105
1111
1117
1123
1129
1135
1141
1147
1153
1159
Average Opacity
(Percent)
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
0
0
0
0
0
0
0
0
0
0
Date
8-15-80
Run
Number
Six-Minute
Time Period
1200 - 1205
1206 - 1211
1212 - 1217
1218 - 1223
1224 - 1229
1230 - 1235
1236 - 1241
1242 - 1247
1248 - 1253
1254 - 1259
Average**
Average Opacity
(Percent)
0
0
0
0
0
1.9
5
5
5
5
2.2
•Run number of concurrent inlet and bypass emission tests.
**Average Cor 1200 - 1259 observation period.
-------
TABLE A-34.
PLANT Z: OPACITY READING AT THE FLUIDIZED
BED COOLER SCRUBBER BYPASS
Date
8-15-80
Run
Number
8-15-80
8-15-80
Six-Minute
T iroe Pe r iod
1100 - 1105
1106 - 1111
1112 - 1117
1118 - 1123
1124 - 1129
1130 - 1135
1136 - 1141
1142 - 1147
1148 - 1153
1154 - 1159
Average
1210 - 1215
1216 - 1221
1222 - 1227
1228 - 1233
1234 - 1239
1240 - 1245
1246 - 1251
1252 - 1257
1258 - 1303
1304 - 1309
Average
1545 - 1550
1551 - 1556
1557 - 1602
1603 - 1608
1609 - 1614
1615 - 1620
1621 - 1626
1627 - 1632
1633 - 1638
1639 - 1644
Average
Average Opacity
(Percent)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
A-88
-------
TABLE A-35. PLANT Z: OPACITY READINGS AT THE COATER AND
SCRUBBER FABRIC FILTER OUTLETS
Coater Baghouse
Bagging Baghouse
Six-Minute
Date Time Period
8-13-80 0845 - 0850
0851 - 0856
0857 - 0902
0903 - 0908
0909 - 0914
0915 - 0920
0921 - 0926
0927 - 0932
0933 - 0938
0939 - 0944
Average
B-13-BO 1255 - 1300
1301 - 1306
1307 - 1312
1313 - 1318
1319 - 1324
1325 - 1330
1331 - 1336
1337 - 1342
1343 - 1348
1349 - 1354
1355 - 1359
Average
B-13-80 1355 - 1400
1401 - 1406
1407 - 1412
1413 - 1418
1419 - 1424
1425 - 1430
1431 - 1436
1437 - 1442
1443 - 1448
1449 - 1454
Average
Average Opacity
(Percent)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Six-Minute Average Opacity
Date Time Period
8-14-80 1014 - 1019
1020 - 1025
1026 - 1031
1032 - 1037
1038 - 1043
1044 - 1049
1050 - 1055
1056 - 1101
1102 - 1107
Average
8-14-80 1123 - 1128
1129 - 1134
1135 - 1140
1141 - 1146
1147 - 1152
Average
8-14-80 1235 - 1240
1241 - 1246
1247 - 1252
1253 - 1258
1259 - 1304
1305 - 1310
1311 - 1316
1317 - 1322
1323 - 1328
1329 - 1334
1335 - 1340
1341 - 1346
1347 - 1352
1353 - 1358
Average
(Percent)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
A-89
-------
100
99» 9M 9t9«
«y. «8PaTP» THAN STATED S!Z£
9O W 70 SO SO *O 30 ZO 10 9
Z i 0.3 0.2 0.1
• - lnl«r A
* - lnl«r 3
ln/«t C
01 02 OS I 2 3 1C 20 30 «O «O SO *J M> 9O 93 9« 99 994 MS
WEIGHT % LESS ^AN STATED SIZE
Figure A-9. Plant Z: Particle size results at the prill
tower scrubber inlet.
-------
2
2
1
X
5
Ul
100
90
20
10
9
2
1
0.9
0.2
OJ
WEIGHT % GREATER THAN STATED SIZE
9 9»« 9» 98 99 9O SO 70 SO JO
t
i
/
*
1
_ffn
//>
'!
/
i
1
i i
i
i
!
i
I
\ J ;
111 1
i
i
;
i
i i
i
! i
i
i '
i i
i i '
• 1
t
i
i
100
90
2O
10
O.S
0.2
OJ 02 OJ ! 2 S >C 20 30 «O SO SO TO SO 90 99 M 99
WEIGHT % LESS THAN STATED SiZE
0.1
99B 99.9
Figure A-10. Plant Z: Particle size results at the prill
tower bypass.
A-91
-------
WEIGHT % GREATER THAN STATED SIZE
100
9O
99 9fl
20
10
O
i :
UJ
g 2
IT
2
0.3
0.2
• Run I
- ?un 3
i l i
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A-95
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APPENDIX A REFERENCES
1. Wade, W.A. and R.W. Cass. (The Research Corporation.) Ammonium
Nitrate Emission Test Report: C.F. Industries. (Prepared for U.S.
Environmental Protection Agency.) Research Triangle Park, North
Carolina. EMB Report 79-NHF-10. November 1979. 119 p.
2. Hansen, M.D., et al. (Midwest Research Institute.) Ammonium
Nitrate Emission Test Report: Swift Chemical Company. (Prepared
for U.S. Environmental Protection Agency.) Research Triangle Park,
North Carolina. EMB Report 79-NHF-ll. July 1980. 85 p.
3. Becvar, D.P., et al. (Engineering-Science, Inc.) Ammonium Nitrate
Emission Test Report: Union Oil Company of California. (Prepared
for U.S. Environmental Protection Agency.) Research Triangle Park,
North Carolina. EMB Report 78-NHF-7. October 1979. 51 p.
4. York Research Corporation. Ammonium Nitrate Emission Test Report:
N-ReN Corporation. (Prepared for U.S. Environmental Protection
Agency.) Research Triangle Park, North Carolina. EMB Report 78-
NHF-5. May 1979. 104 p.
5. Kniskern, R.A., et al. (York Research Corporation.) Ammonium
Nitrate Emission Test Report: Cominco American, Inc. Beatrice,
Nebraska. (Prepared for U.S. Environmental Protection Agency.)
Research Triangle Park, N.C. EMB Report 79-NHF-9. April 1979. 59
P.
6. Wade, W.A., et al. (TRC Environmental Consultants, Inc.) Ammonium
Nitrate Emission Test Report: Columbia Nitrogen Corporation.
(Prepared for U.S. Environmental Protection Agency.) Research
Triangle Park, North Carolina. EMB Report 80-NHF-16. January
1981. 126 p.
A-96
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APPENDIX B
Ammonium Nitrate Emission Measurement
B.I Emission Measurement Methods
B.I.I Background
The standard method for determining particulate emissions for
stationary sources is EPA Method 5, whereby a particulate sample is
extracted isokinetically from a source and is collected on a heated
filter. The particulate mass is then determined gravimetrically.
Initial evaluations by EPA and others of the applicability of Method 5
for ammonium nitrate (AN) sampling indicated that in fact the standard
1 p
procedures of Method 5 would not be practical. ' Factors that affected
the sampling and analysis procedures of Method 5 included the following:
• High water-solubility of AN (greater than 1 gram per ml water);
• Relatively high vapor pressure and volatility of AN (AN
decomposes at 483 K (410°F)); and,
• High moisture levels present at certain AN emission sources
(percent moisture exceeding 50 percent).
As a result of these factors, major modifications to Method 5 were
adopted. A summary of these modifications and the reasons for each are
presented in the remainder of Section B.I.
B.I.2 Brief Summary of AN Method Development
Preliminary emission testing programs by industry and EPA in 1975
and 1976 demonstrated the applicability of the following modifications
to Method 5 for AN sampling and analysis:
• Use of water-filled impingers as the primary AN collection
devices;
• Placement of the filter after the water impingers as a back-up
collector;
• Use of a specific ion electrode (SIE) for measurement of AN in
the impinger water;
• Use of a water rinse instead of an acetone rinse because of
the explosion hazard when organic solvents mix with AN;
B-l
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• Use of an in-stack orifice in high water-content sources where
isokinetic sampling rates could not be maintained using Method 5
procedures.
Further minor modifications were incorporated into the AN method during
six emission testing programs conducted by EPA from November 1978 to
August 1980. The results of these programs demonstrated the applicability
of the recommended EPA Method ("modified" Method 5; AN-MOD 5) for AN
sampling and analysis. The modifications incorporated into AN-MOD 5 are
summarized as follows:
• Use of five impingers in the following sequence: impingers 1
and 2 each contain 100 ml water (for AN collection), impinger
3 contains 100 ml IN sulfuric acid (to protect sampling train
components from ammonia), impinger 4 is empty and impinger 5
contains silica gel;
• Elimination of the in-train filter;
• Sample Recovery and Analysis: combine the contents of impingers
1 and 2 and the probe wash, filter for insoluble particulate,
and analyze the filtrate for AN by SIE; measure the contents
of impingers 3 and 4 for condensed moisture, and then discard
the contents.
B.I.3 Detailed Development of AN Sampling and Analysis Method
B.I.3.1 Initial Method Development
Ammonium nitrate sampling modifications to Method 5 were needed
because of the following source conditions:
• AN has a substantial vapor pressure even as a solid, and if a
sample is heated in a probe or on a filter for extended periods
of time it would tend to decompose.3
• Industry sources estimated that a large fraction of AN particulate
matter would be small enough (less than 0.3 microns in diameter)
to pass through a Method 5 filter.
• The high-water-solubility of AN and the potential ineffectiveness
of a filter implied that water impingers in the sampling train
would be an efficient AN particulate collector.
B-2
-------
• Ammonia is an additional pollutant emitted from the AN manufacturing
processes. Ammonia was considered a secondary pollutant in
the test work plan but could not be efficiently collected in
the Method 5 sampling train water impingers. Additional
impingers containing acid would be required.
• Method 5 could not be performed effectively in high moisture
sampling situations, such as at neutralizers and evaporators,
because isokinetic sampling conditions could not be maintained.
Factors that would affect AN analysis procedures were the following:
• With water impingers as the primary particulate collector, the
water contents of the sampling train impingers would have to
be analyzed for AN.
• The volatility of AN would preclude rapid heating of the
samples to evaporate water in order to do a gravimetric analysis.
At the same time, evaporating large quantities of water without
heating would be inefficient and tedious.
• The insoluble fraction of particulate emitted from AN sources
was considered to be insignificant.
• The specific ion electrode procedure for AN analysis is
applicable to a wide range of AN concentrations, can be performed
easily and quickly in the field, and is recommended and widely
used by industry. This procedure measures nitrate (NOZ)
from which AN is calculated stoichiometrically.
An emission testing program was performed by plant personnel on
2
neutralizer and evaporator emissions at an AN plant in July 1975.
Water impingers were used to collect AN particulate, an in-train glass-
wool plug was placed after the water impingers, and nitrate analyses of
the impinger contents were performed with a specific ion electrode. The
Method 5 procedures for sample flowrate measurement and control were
followed; however, the high moisture content of the sampled streams made
isokinetic sampling difficult to maintain.
EPA conducted an emission testing program in March 1976 on a
neutralizer stack at an AN facility.2 The purpose of this initial
B-3
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program was to determine the applicability of the sampling and analysis
procedures used during the 1975 program. In addition, evaluations of
other Method 5 modifications were performed in order to develop an
initial AN test method for the testing program. An in-stack orifice was
used to control the sampling rate, and a heated filter was placed after
the impingers. Field and laboratory samples were analyzed both gravimetrically
and by the specific ion electrode (SIE) procedure. The results of this
program showed that:
• The AN sampling and analysis method was practical and gave
reproducible results;
• An in-stack orifice could be used successfully in high moisture
content gas streams in order to maintain isokinetic sampling
conditions; and,
• The SIE analysis procedure yielded results that agreed within
1 percent of known standards. Gravimetric results agreed only
within 5 percent of known standards.
The AN sampling and analysis method recommended for the testing
program in November 1978 included the following specific Method 5 modifications:
Sampling
• Six impingers in series, with the following sequence: impingers
1 and 2 each contain 100 ml water, impingers 3 and 4 each
contain 100 ml IN sulfuric acid, impinger 5 is empty, and
impinger 6 contains silica gel.
• A filter, heated if necessary to prevent condensation, placed
between impingers 2 and 3. Filter temperature should not
exceed the decomposition temperature of AN 283 K (410°F).
Analysis
• Combine the contents of impingers 1 and 2, the probe washes
and the train filter (allowing the filter catch to dissolve);
filter this solution with a vacuum filtration apparatus to
remove insoluble particulate; split the filtrate; analyze one
portion for nitrate by SIE and the other portion for ammonia
by direct nesslerization.
8-4
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• Combine the contents of impingers 3, 4, and 5 and analyze a
portion for nitrate by SIE and a portion for ammonia by direct
nesslerization.
The test work plan for the technical document included emission tests on
all AN process units having significant emissions: neutralizers, evaporators,
prill towers, granulators, predryers, dryers and coolers. The sampling
method would differ slightly for the neutralizers and evaporators because
of the high moisture content of these units. An in-stack orifice would
be necessary in the sampling train at a neutralizer 'or evaporator in
order to maintain isokinetic sampling conditions.
Insoluble participate analysis was included in this initial method
because most AN plants use a clay coating or additive to protect the
final solid AN product. Some final product is often recycled back to
the process liquors, and particulate emissions may result from the weak
liquor used in scrubber systems. Additional sources of insoluble particulate
are believed to be pipe scale and rust in the scrubber systems.
Ammonia was considered a secondary pollutant in the test work plan
and is most efficiently collected in acid impingers. Two acid impingers
were therefore included in the sampling train for ammonia collection.
The in-train filter served as a backup collector to prevent the carry
over of particulate or particulate-laden water droplets.
The AN collection medium (water) and the ammonia collection medium
(acid) are separate during sampling and analysis because of the susceptibility
of the nitrate SIE analysis procedure to interference in high ionic
strength solutions.13*14 Because of its high water solubility, nearly
all sampled AN will be collected in the water impingers and very little
collected in the acid impingers.
Ammonium nitrate in solution exists as nitrate ions and ammonium
ions. Therefore, if only AN is emitter and sampled, then either nitrate
or ammonia could be measured to quantify AN particulate emissions. In
the AN production process, however, either ammonia or nitrate will be
present in excess (AN is formed by combining ammonia and nitric acid).
The emission tests for this study were all performed at AN facilities
B-5
-------
that operated with an excess of ammonia. Nitrate was therefore the
limiting species and any measured nitrate originated as AN. Nitrate and
ammonia analyses were performed during the tests in order to quantify AN
particulate emissions. The excess species (ammonia) was sampled and
analyzed to document its excess.
B.I.3.2 Emission Testing Program at the First Five Plants
From November 1978 through June 1979, EPA conducted five emission
testing programs at five different AN plants using the above (modified
Method 5) sampling and analytical procedures. Evaporator, granulator
and cooler emissions were tested at the first AN plant, with an in-stack
orifice used at the high moisture locations. The in-train filter was
analyzed separately for AN particulate and insoluble particulate. Less
than 0.2% of the total AN catch was found on the filter. The percent
insoluble particulate catch (insoluble particulate/total particulate)
averaged about 3% for uncontrolled emissions and about 8% for controlled
emissions. No AN was detected in the acid impingers.
At the second plant, also tested in November 1978, controlled and
uncontrolled cooler emissions were evaluated. The train filter was
analyzed separately for particulate, and no AN was found on the filter.
No AN was detected in the acid impingers. The percent insoluble particulate
catch averaged about 0.2% for uncontrolled emissions and about 6% for
controlled emissions.
The third plant was tested in March 1979 for uncontrolled and
controlled granulator emissions and uncontrolled cooler emissions. The
train filter was combined with the water impinger contents and probe
washes and was not analyzed separately. The percent insoluble particulate
catch averaged about 0.02% for the granulator uncontrolled emissions,
and about 4% for the granulator controlled emissions. Only very slight
amounts of AN were detected in the uncontrolled granulator acid impingers
(less than 0.5% of total catch). Significant amounts of AN were measured
in the controlled granulator acid impingers (about 30% of total catch),
but the interfering effects of the acid make these results suspect. '
B-6
-------
g
The fourth plant was tested in March 1979, for uncontrolled emissions
from the predryer, dryer and cooler operations. The train filter was
not analyzed separately. The percent insoluble particulate catch averaged
about 0.6% of the total particulate catch for all the process operations
tested. Approximately 3% of the total AN catch was detected in the acid
13 14
impingers, and these results are suspect because of acid interference. '
Q
The fifth plant was tested in May and June 1979 for controlled and
uncontrolled emissions from a prill tower, prill cooler, evaporators and
neutralizers. The train filter was not analyzed separately. The percent.
insoluble particulate catch for uncontrolled emissions averaged 4.4%,
0.9%, and 1.2% at the prill tower, cooler and neutralizer, respectively;
and 5.8%, 10%, and 18% for the controlled emissions at the same process
units. Acid impinger samples were not analyzed for nitrate. The
neutralizer and evaporator samples contained very high concentrations of
ammonia compared to AN. As a result, some positive interference in the
AN analyses of these samples was evident due to their high background
ionic strength.
The results of these five emission testing programs demonstrated
that:
• Little or no particulate is collected by the in-train filter;
• Nearly all AN is collected in the water impingers; and,
• The SIE nitrate analysis is subject to interference in high
ionic strength solutions. This interference will normally be
confined to neutralizer/evaporator emission samples.
B.I.3.4 Method Modifications
EPA further modified the AN sampling and analytical method to
reflect the findings of the first five testing programs and to discontinue
the requirement for ammonia sampling and analysis. No immediate need
for an ammonia emissions evaluation was foreseen. The modifications
consisted of the following:
Sampling
• Use of five impingers with the following sequence: impingers
1 and 2 each contain 100 ml water (for AN collection), impinger
B-7
-------
3 contains 100 ml IN fUSO. (to protect sampling train components
from ammonia), impinger 4 is empty and impinger 5 contains
silica gel.
• Elimination of the in-train filter.
Analysis
• Combine the contents of impingers 1 and 2 and the probe washes;
filter this combined solution for insoluble particulate and
analyze the filtrate for nitrate by SIE.
• Measure the volume of the contents of impingers 3 and 4 for
condensed moisture, and then discard the contents.
These modifications represent the recommended EPA Method (AN-MOD 5) for
AN emission testing. In situations where ammonia sampling and analysis
is of interest, an additional impinger (containing 100 ml IN H^SO.) can
be added to the train directly in front of the empty impinger. The
contents of the first two impingers are then analyzed for nitrate by SIE
and for ammonia by SIE or direct nesslerization. The contents of the
third and fourth impingers are analyzed for ammonia only. The two
ammonia analysis methods (SIE and direct nesslerization) have been shown
to yield equivalent results. »
B.I.3.5 Sixth Emission Testing Program
EPA conducted a sixth emission testing program in August 1980 on
controlled and uncontrolled prill tower, predryer, dryer and cooler
12
emissions. The recommended AN-MOD 5 was used and modified for ammonia
sampling and analysis as described above. Ammonia analyses were performed
with the SIE procedure. The percent insoluble particulate catch for the
prill tower and dryer controlled emissions averaged 27% and 1.1%, respectively.
The prill tower insoluble particulate was believed to be primarily clay
coating material.
The results of this emission testing program demonstrated the
utility and economy of the recommended method. The AN and ammonia SIE
analytical methods required a minimum of equipment and field laboratory
space and all analyses were performed on-site within 24 hours of sample
collection. The ability to perform sample analyses quickly in the field
B-B
-------
allows for rapid determination of emission values and evaluation of
sampling technique.
B.I.4 Potential Problems with the Recommended Method
Potential difficulties that could affect the use of the recommended
method are:
• Decomposition of AN in the probe at temperatures exceeding
483 K (410°F);
• Interference in the nitrate SIE analysis procedure due to high
ionic strength sample solutions;
• Emission tests performed at AN plants operating with excess
nitric acid;
• Incomparability of AN-MOD 5 and Method 5 data.
By maintaining probe temperatures at about 6 K (10°F) above stack temperature,
sample decomposition and moisture condensation in the probe can be
avoided. Most emission control devices operate at or near saturation
and at temperatures less than 322 K (120°F).
Interference in the nitrate analysis would be primarily confined to
neutralizer or evaporator emission samples containing high concentrations
of ammonia. The interference is characteristic of the operation of the
nitrate SIE. Sample dilution may not eliminate the problem because the
degree of interference depends on the relative strength of the interfering
ion concentration. The analytical technique of known addition measurement
can be used to estimate nitrate concentrations in high ionic strength
solutions.
A sampling and analytical method that would determine total ammonia
would be required in order to measure AN emissions at plants operating
with excess nitric acid (with ammonia therefore as the limiting species).
With AN-MOD 5 there would be no way to distinguish between nitrate from
AN emissions and nitrate from excess nitric acid.
B.I.5 Relationship of Data Gathered Under Test Programs to Data Gathered
with the Recommended Method
The recommended AN-MOD 5 is identical to the method used on the
emission testing programs with the exception of the following minor
changes incorporated after the first five test programs:
B-9
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• elimination of the in-train filter;
• elimination of acid impinger nitrate analyses; and,
• elimination of ammonia sampling and analysis.
These changes simplified the sampling and analytical method, eliminating
unnecessary procedural steps. For this reason the data gathered during
the test programs are comparable to data gathered with the recommended
AN-MOD 5.
B.2 Performance Test Methods
AN-MOD 5 - "Determination of Particulate Emissions from Ammonium
Nitrate Plants" - is the recommended test method for ammonium nitrate
facilities. This method incorporates modifications to the standard
Method 5 that reflect the unique characteristics of AN and AN sources,
as discussed in Section B.I above. These modifications are summarized
as follows:
• Collection of ammonium nitrate in water impingers;
• Elimination of an in-train filter; and,
• Analysis of water impinger contents for nitrate by a specific
ion electrode and for insoluble particulate by filtration and
weighing.
Six emission testing programs conducted by EPA at AN facilities
demonstrated that the recommended test method is a workable and efficient
means for accurately sampling and analyzing ammonium nitrate emissions.
During the course of these emission testing programs, the method was
modified to its present form. The modifications eliminated procedures
that were shown through the emission testing programs to be unnecessary.
Therefore, as discussed in Section B.I, the data gathered during these
testing programs will be comparable to data gathered using the recommended
test method.
Four potential difficulties could affect the use of the recommended
method:
• Decomposition of AN in the probe at elevated temperatures;
• Interference in the nitrate SIE analysis procedure due to high
ionic strength sample solutions;
B-10
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• Emission tests performed at AN plants operating with excess
nitric acid; and,
• Incomparability of AN-MOD 5 and Method 5 data.
These difficulties are discussed in Section B.I. The interference
problem is primarily confined to emission samples from neutralizers and
evaporators.
B-ll
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APPENDIX B REFERENCES
1. Grove, J.D., "Prill Tower Sampling Approaches: Urea and Ammonium
Nitrate Processes." Entropy Environmentalists, Inc. Prepared for
U.S. EPA under Contract 68-01-4148, Task No. 32, October 1977.
2. Kelly, Winton E., "Development and Evaluation of an Alternate
Particulate Test Procedure for Ammonium Nitrate Facilities." U.S.
EPA, OAQPS, ESED, Emission Measurement Branch, Research Triangle
Park, North Carolina, April 1977.
3. The Condensed Chemical Dictionary, 9th edition, Van Nostrand Reinhold
Company, 1977, p. 51.
4. Standard Methods of Water and Wastewater Analysis, APHA, AWWA,
WPCA, 14th Edition, 1975, p. 412.
5. EPA Report 78-NHF-5, "Emission Test Report, N-ReN Corporation,
Pryor, Oklahoma." Prepared by York Research Corporation under EPA
Contract 68-02-2819, Work Assignment 8.
6. EPA Report 79-NHF-9, "Emission Test Report, Cominco American, Inc.,
Beatrice, Nebraska," Prepared by York Research Corporation under
EPA Contract 68-02-2819, Work Assignment 10.
7. EPA Report 79-NHF-ll, "Emission Test Report, Swift Chemical Company,
Beaumont, Texas." Prepared by Midwest Research Institute under EPA
Contract 68-02-2184, Work Assignment 18.
8. EPA Report 78-NHF-7, "Emission Test Report, Union Oil Company of
California, Brea, California." Prepared by Engineering-Science
under EPA Contract 68-02-2815, Work Assignment 26.
9. EPA Report 79-NHF-10, "Emission Test Report, CF Industries, Inc.,
Harrison, Tennessee." Prepared by TRC-Environmental Consultants,
Inc., under EPA Contract 68-02-2820, Work Assignment 12.
10. EPA Report 79-NHF-3, "Emission Test Report W.R. Grace and Co.,
Memphis, Tennessee." Prepared by TRC-Environmental Consultants,
Inc., under EPA Contract 68-02-2820, Work Assignment 9.
11. EPA Report 80-NHF-14, "Emission Test Report, Reichhold Chemicals,
Inc., St. Helens, Oregon." Prepared by TRC-Environmental Consultants,
Inc., under EPA Contract 68-02-2820, Work Assignment 19.
12. EPA Report 80-NHF-16, "Emission Test Report, Columbia Nitrogen
Corporation, Augusta, Georgia." Prepared by TRC-Environmental
Consultants, Inc., under EPA Contract 68-02-2820, Work Assignment
25.
B-12
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13. Orion Research Incorporated Instruction Manuals for Nitrate Ion
Electrode Model 93-07 and Specific Ion Meters Models 407 A/F and
407 A/L.
14. Driscoll, J.N. et al, "Determination of Oxides of Nitrogen in
Combustion Effluents with the Nitrate Ion Selective Electrode,"
presented at APCA Meeting, June 1971.
B-13
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TECHNICAL REPORT DATA
(Please read Jnsmtcnons on the reverse before completing)
. REPORT NO. '
EPA-450/3-81-002
3. RECIPIENT'S ACCESSION NO.
A. TITLE AND SUBTITLE
Technical Document for the Ammonium Nitrate Industry
5. REPORT DATE
January 1981
6. PERFORMING ORGANIZATION CODE
7. AUTrlOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME ANO ADDRESS
10. PROGRAM ELEMENT NO.
Radian Corporation
3024 Pickett Road
Durham, North Carolina
27705
11. CONTRACT/GRANT NO.
68-02-3058
12. SPONSORING AGENCY NAME ANO ADDRESS
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emission Standards and Engineering Division
Industrial Studies Branch
Research Trianle Park. North Carolina ?7711
13. TYPE OF REPORT ANO PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This report presents information on the emission levels, control techniques, and
costs associated with the control of particulate emission sources and facilities in
the ammonium nitrate solids producing industry. Sources of emissions include prill
towers, granulators, predryers, dryers, and coolers. Alternative control techniques
and supporting data are described and discussed, and an analysis of environmental and
economic impacts of control techniques are presented.
17.
KEY WORDS AND DOCUMENT ANALYSIS
a.
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Air Pollution
Control Technology
Ammonium Nitrate
Particulate Emissions
Air Pollution Control
Particulate Control
Wet Scrubbers
Wetted Fibrous Filters
'•3. OiSTRiSUT.GN STATHMEN1
Unlimited
19. SECURITY CLASS (Tins Report/
Unclassified
•21. NO. OF PAGES
I 20. SECURITY CLASS I This page I
Unclassified
i22. PRICE
£?A Firm 2220-1 (Rev. -1-77) =«swiOijs
is OBSOLETE
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