Note: EPA no longer updates this information,
but it may be useful as a reference or resource.
                                                                                   August 1994
               DEVELOPMENT AND SELECTION OF AMMONIA EMISSION FACTORS

                                             Final Report
                                                  by
                             R. Battye, W. Battye, C. Overcash, and S. Fudge
                                          EC/R Incorporated
                                     Durham, North Carolina 27707
                                   EPA Contract Number 68-D3-0034
                                         Work Assignment 0-3
                                       Work Assignment Manager

                                          William G. Benjey*
                        Atmospheric Research and Exposure Assessment Laboratory
                                  U.S. Environmental Protection Agency
                              Research Triangle Park, North Carolina 27711
                                 *On assignment from the National Oceanic and Atmospheric
                                     Administration, U. S. Department of Commerce
                                             Prepared for:

                                  U.S. Environmental Protection Agency
                                   Office of Research and Development
                                        Washington, D.C.  20460

-------
                                   DISCLAIMER

The information in this document has been funded wholly or in part by the United States
Environmental Protection Agency under Contract 68-D3-0034 to EC/R Incorporated. It has been
subjected to the Agency's peer and administrative review, and it has been approved for
publication as an EPA document. Mention of trade names of commercial products does not
constitute endorsement or recommendation for use.

-------
                                TABLE OF CONTENTS

Abstract	  iii
List of Tables	vii
List of Figures	  ix
Executive Summary	  xi
Section  1:  Introduction 	  1-1
      References for Section I	  1-4
Section 2:  Ammonia Emissions From Animal Husbandry	2-1
      2.1  Summary of Recent Research in Europe  	2-1
      2.2  Factors Influencing Ammonia Emissions from Animal Husbandry  	2-3
      2.3  NAPAP Emission Factors for Animal Husbandry	2-4
      2.4  Comparison of Ammonia Emission Factors for Animal Husbandry  	2-6
      2.5  Animal Husbandry Activity Data for the United States 	2-7
             2.5.1 Cattle and Calves 	2-9
             2.5.2 Hogs and Pigs	2-9
             2.5.3 Poultry	 2-11
             2.5.4 Sheep and Lambs 	 2-12
      2.6  Ammonia Emission Factors for Miscellaneous Animal Categories	 2-12
      2.7  Recommended Animal Husbandry Emission Factors and Source
              Classification Codes  	 2-12
      References for'Section 2	 2-18
Section 3: Ammonia Emissions from Fertilizer Application  	  3-1
      3.1 European Emission Factors 	  3-1
      3.2 Recent Volatilization Research	  3-3
             3.2.1 Urea Applied	  3-5
             3.2.2 Urea Applied to Flooded Paddies	  3-7
             3.2.3 Ammonium sulfate	  3-7
      3.3 Summary of Parameters Affecting Ammonia Emissions 	  3-7
      3.4 Availability of Activity Data	  3-8
      3.5 Recommended NH3 Emission Factors 	  3-8
      References for Section 3  	 3-11
Section 4: Ammonia Emissions in Industry  	4-1
      4.1 Categories Included in the 1985 NAPAP Inventory  	4-1
      4.2 Additional Sources of Ammonia Emission  	4-1
             4.2.1 Beet Sugar Production	4-5
             4.2.2. Froth Flotation in Mineral Processing	4-6
             4.2.3 Mineral Wool (Fiberglass) Production	4-8
             4.2.4 Pulp and Paper  	4-9
             4.2.5 Emission Factors Provided by Other Sources 	 4-10
             4.2.6 Other Sources (For Which Emission Factors
                         Have Not Been Developed)	 4-11
      References for Section 4  	 4-15
                                           in

-------
                          TABLE OF CONTENTS (continued)

Section 5: Ammonia Emissions from Combustion 	  5-1
       5.1  Ammonia Emission Factors for Coal Combustion  	  5-1
       5.2  Ammonia Emissions from Fuel Oil and Natural Gas Combustion	  5-3
       5.3  Mobile Sources	  5-4
       5.4  Use Of Ammonia and Urea to Reduce, Catalytically Or Noncatalytically,
             Nitrogen Oxides in Combustion Gases  	  5-4
             5.4.1 Selective Catalytic Reduction	  5-5
             5.4.2 Selective Non-Catalytic Reduction	  5-6
             5.4.3 Ammonia Emissions and Emission Factors	  5-6
       5.5  Biomass Burning	  5-9
       5.6  Recommended Combustion Ammonia Emission Factors and Classification
             Codes  	  5-9
       References for Section 5  	  5-9
Section 6: Miscellaneous Sources	  5-12
       6.1  Human Breath and Perspiration	  6-1
       6.2  Publicly Owned Treatment Works	  6-1
       6.3  Non-Agricultural Soils 	  6-4
       6.4  Use Of Ammonia as a Refrigerant	  6-6
       6.5 Ammonia Spills  	  6-7
       6.6  Recommended Ammonia Emission Factors for Miscellaneous Source
              Categories	  6-7
       References for Section 6  	  6-7
Section 7: Conclusions and Recommendations	  6-10
       7.1 Recommended Emission Factors  	  7-1
       7.2 Relative Source Strength in the U.S	  7-1
       7.3  Recommended Research	  7-13
       References for Section 7  	  7-13
Appendix A: Criteria for Assessing Emission Factors	  7-17
       A.I  Discussion Of Criteria 	A-l
       A.2 Rating System  	A-2
       Reference for Section A	A-4
                                           IV

-------
                                  LIST OF TABLES
Table 2-1. Animals of Husbandry Emission Factors	2-2
Table 2-2. 1985 NAPAP Animal Husbandry EmissionFactors and Animal
          Populations	2-6
Table 2-3. Comparison of Animals of Husbandry Emission Factors	2-7
Table 2-4. Emission Factors Used in Different Emission Inventories for Animal Sourcesof
          Ammonia  	2-8
Table 2-5. U.S. Agriculture Activity Classification and Emission Factors for Cattle
          and Calves	  2-10
Table 2-6. U.S. Agriculture Activity Classifications and Emission Factors for Hogs
          and Pigs   	  2-11
Table 2-7. U.S. Agriculture Activity Classification and Emission Factors for Poultry . . 2-13
Table 2-8. Ammonia Emission Factors for Miscellaneous Animals  	  2-14
Table 2-9. Recommended Ammonia Emission Factors for Animal Husbandry	  2-15
Table 3- 1. Summary of U.S. Nitrogen Fertilizer Usage	 3-2
Table 3-2. Summary of European Emission Factors for Fertilizer Application	 3-3
Table 3-3. Summary of Recent Measurements of Ammonia Volatilization from
          Fertilizer  	 3-4
Table 3-4. Activity Data Available for Fertilizer Application	 3-9
Table 3-5. Recommended Ammonia Emission Factors from Fertilizer Application  ....  3-10
Table 4-1. Summary of Industrial Ammonia Emission Factors	4-2
Table 4-2. Ammonia Emission Factors for Beet Sugar Production  	4-6
Table 4-3. Ammonia Emission Factors for Mineral Ore Processing by Froth
          Flotation  	4-7
Table 4-4. Ammonia Emission Factors Developed from the California ATEDS Data
          Base      	  4-11
Table 4-5. Summary of Ammonia Emissions Reported in TRIS	  4-13
Table 4-6. List of Discrete Major Sources of Ammonia with No Applicable Emission
          Factors     	  4-14
Table 5-1. Coal Combustion Ammonia Emission Factors  	 5-2
Table 5-2. NAPAP Fuel Oil and Natural Gas Emission Factors5-3
Table 5-3. Mobile Source Emission Factors  	 5-5
Table 5-4. Summary of Ammonia Slip Data for SCR and SNCR Installations	 5-7
Table 5-5. SCR and  SNCR Ammonia Emission Factors  	 5-8
Table 5-6. Recommended Emission Factors for Combustion Sources	  5-10
Table 6- 1 Ammonia Emission Factors for Human Sources	 6-3
Table 6-2. Ammonia Emission Factors for POTW'S   	 6-4
Table 6-3. Ammonia Emission Factors for Non-Agricultural Soils	 6-6
Table 6-4. Summary of Accidental Releases  of Ammonia	 6-8
Table 6-5. Recommended Emission Factors  for Miscellaneous Sources	 6-9

-------
                            LIST OF TABLES (continued)

Table 7-1.  Recommended Ammonia Emission Factors for Animal Husbandry	 7-2
Table 7-2.  Recommended Ammonia Emission Factors from Fertilizer Application  	7-5
Table 7-3.  Summary of industrial Ammonia Emission Factors	 7-6
Table 7-4.  Recommended Emission Factors for Combustion Sources	 7-9
Table 7-5.  Recommended Emission Factors for Miscellaneous Sources	 7-11
Table 7-6.  Recommended Ammonia Emission Factor Research Projects	 7-13
                                         VI

-------
                                 LIST OF FIGURES




FIGURE 1.  Relative contribution of ammonia emissions from different source categories




FIGURE 7-1. Relative contribution of ammonia emissions from different source categories
                                          vn

-------
                                EXECUTIVE SUMMARY

       This report compiles and reviews recent (published after 1985) literature on sources of
ammonia (NH3) emissions and NH3 emission factors.  This compilation contains the most recent
research in the field of NH3 emission factors. The primary focus of this report is on NH3 emission
factors, as opposed to estimates of total NH3 emissions. Emission estimates are, however, made
for some categories, in Order to determine the relative importance of the source category to
NH3emissions, and to assist in developing priorities for future NH3 emission factor research.

       Ammonia emissions can not be speciated from VOC or PM emissions, because as an
inorganic gaseous chemical, NH3 is not included in YOC emissions estimates and, as a gas, it is
not included in PM emissions estimates.  Therefore, it is necessary to utilize emission factors for
estimating NH3 emissions.

       Ammonia emissions are important in atmospheric models,  because ammonia is the most
important almine constituent in the atmospheric boundary  layer. The fate of NH3 released from
the ground into the atmosphere is complex and varied, but this NH3 can have a significant effect
on oxidation rates, particularly in clouds, and hence on deposition rates of acidic -species. This
effect is predicted not only by models for the heterogeneous chemistry of cloud droplets, but has
also been confirmed by observation and experimentation.  The long range transport of
atmospheric sulfur dioxide and nitrogen oxide,  and the products of their reactions, have long been
studied in relation to acidic deposition. However, much less research has been done on the effects
of atmospheric NH3, although it is well known  that over large areas of Europe, acid precipitation
is failing in which up to 70 percent of the original acid is neutralized by NH3.

       This report presents a narrative on the recent research for the known substantial sources
of ammonia emissions. Emission factors resulting from this investigation are compared with the
factors published by National Acid Precipitation Assessment Program (NAPAP), as compiled by
Misenheimer et al (1 987), and later by Warn et al. (I 990). Recommendations on the most
reliable NH3emission factors for use in the United States are made. For each recommended
emission factor, a point source classification code (SCC) or area and mobile source (AMS) code
is presented, along with an emission factor rating.

       Recent research on NH3 emissions as it relates to acid deposition, is concentrated in the '
European community (specifically, in the Netherlands, Great Britain, and Scandinavia).  In
addition, there has been some research conducted in Australia. The majority of the NH3 emissions
studied in current inventories originates from agricultural sources.  These agricultural sources are
mainly livestock wastes, with fertilizer applications also providing a significant proportion.  NH3
emission estimate numbers vary widely between different  studies,  but the authors of recent
European inventories all consider animal wastes and fertilizers to be responsible for 90% or more
of the anthropogenic NH3 emissions. Some of the more recent inventories in Europe even
exclude contributions from industrial facilities entirely, noting that they are insignificant relative to
                                            Vlll

-------
the agricultural sources.

       Although the European inventories currently focus on agricultural sources, there is
evidence that additional, significant sources of ammonia may exist.  In a modelling study of acid
deposition, Metcalfe et al. (1989) suggested that the current estimates of NH3 emissions in the
U.K. were too low to explain the concentrations of ammonium in precipitation, and that there
may be other sources of NH3 which have not yet been considered in budget studies
(Lee et al, 1992).  Other research, principally in support of global climate change research,
suggests that there may be significant NH3 emissions from undisturbed soils and biomass burn-ing.

       Much of the research obtained and reviewed',in this report concerns the measurement of
NH3, in which results were generally reported as. experimental, rather than as emission factors-
The majority of NH3 emission factors available  in the literature are discussed relative to the
development of an emission inventory. In the development of an emission inventory, emission
factors are often either developed from the experimental measurement literature, or are borrowed
directly from other bodies of work. The primary source for the emission factors reviewed in this
report is the body of recent emission inventory literature.  The experimental measurement
literature is also reviewed, to provide detail on how the measurements were made.  This review
contributes to understanding the uncertainty of the emission factors, addresses the extent to which
the factors presented incorporate the most recent research, and identifies data gaps for future
emission factor development.

       The most recent NH3 inventory prepared in the U.S. is the Emissions Inventory for the
National Particulate Matter Study which used Bureau of Economic Activity data to grow the
1985 NAPAP inventory to the  1990 study year. Other recent studies include the following:
ApSimon et al. (1987) published an inventory for the U.K. for the 1981 study year; Buijisman
(1987) published a 1982 inventory of NH, for Europe the same year; Erisman (I 989) published a
1987 and 1988 inventory for the -Netherlands; M611er and Schieferdecker (1989) published NH3
estimates through 1985 for the G.D.R.; Kruse et al (1989) published an updated inventory for
Great Britain; Denmead (1990) published an inventory for Australia; and, finally, the most recent
inventory of Europe was published by Asman (1992).  Lee and Longhurst (1993) published the
most recent inventory  for Great Britain. Additional inventories have been published for European
countries; however, these publications were not translated into English and were not reviewed in
this report.

       The NH3 emission factors recommended for use in future U.S. inventories include the
European factors for agricultural sources (animal husbandry and fertilizer application), the
Compilation of Air Pollutant Emission Factors - Volume I (AP-42) for the majority of the
stationary industrial sources, and the NAPAP factors for the majority of the combustion sources
(including coal, oil, natural gas, and mobile  sources), human breath and perspiration, and publicly
owned treatment works (POTW's). New emission factors are developed for beet sugar
production, froth flotation in mineral processing, mineral wool (fiberglass) production,
refrigeration, and  selective catalytic and noncatalytic reduction (SCR and SNCR) for control of
nitrogen oxide (NOx)  emissions.  Discreet industrial sources of NH3 with no

                                            ix

-------
corresponding emission factors, are identified through the Toxic Release Inventory.

       Estimates of NH3 emissions in the U.S. are graphically illustrated in Figure 7-1. These
emission estimates are not comprehensive, and are presented only to illustrate the relative
magnitude of these emissions, in order to frame the recommendations for future research.  These
rough estimates of U.S. NH3emissions indicate that agricultural practices, specifically animal
husbandry and fertilizer application, dominate emissions here just as they do in Europe. Industrial
emissions of ammonia and ammonia emissions from combustion (excluding, open or biomass
burning) are relatively insignificant. Emissions from POTWs and refrigeration may be significant,
based upon the current information gathered.  Emission factors for refrigeration and POTWs have
a rating of E, and further research into these sources is recommended.
Figure 1. Relative contribution of ammonia mwons from different source categories.
                                                Cattle are? Gal vat £43.
  Hoys ana- P,gs C1D.-«o
                                                                 \naustfy A?-42 CO- 0*3

                                                                 R»f r I gere 1 1 on C 5 . H j
                                                                      ion
                                                               Hurat* f 1,2*
                                                        Fsrr.iii«r ADO Meat ion C9 5*3

                                                  Shaap & loirtas CO Titj
       Estimates of NH3 from biomass burning and undisturbed soils were not made, due to the
unavailability of an emission factor for biomass burning and of activity data for undisturbed soils.
Recent research indicates that these two categories may contribute significantly (up to half) to the
global budget of NH3 emissions.

       Five research areas are recommended to enhance the quality of ammonia emission factors
presented in this report. The five research areas are:

       Investigate the recent global climate literature on ammonia from undisturbed soils. Merge
       the literature on emission fluxes with ammonia new land use land cover data categories, to

-------
develop emission factors for the biogenic plants area and mobile source, classification
category.

Investigate recent literature on ammonia emissions from biomass burning. Integrate the
data results with information in the U.S. on naturally occurring f es to develop emission
factors for the U.S. Also, investigate any information on NH3 emissions from the chemical
agents used to fight these naturally occurring fires.

Research the primary references for the animal husbandry emission factors, in order to
provide more accurate linkages with the U.S. Department of Agricultare statistics. In
addition, investigate the discrepancy in the emission factors for sheep presented by Asman
(1992) and Denmead (1990).

Develop temporal profiles for the larger NH3 emissions categories. Specifically,
investigate the seasonal nature of the animal husbandry and fertilizer application emissions.

Confidence in the emission factors reported for refrigeration, POTWS,  and selective
catalytic and non-catalytic reduction (for control of NO. emissions), may be improved
with additional research. Refrigeration  contributes a significant portion of the ammonia
inventory (about 5 %); however, this factor was developed based on a material balance.
POTWs also contribute a significant amount of ammonia (about 2 %); however,  additional
research is ongoing in the United Kingdom and California that may improve the  accuracy
of this emission factor.
                                     XI

-------
                                       SECTION 1

                                    INTRODUCTION
       Sources of ammonia (NH3) emissions and NH3 emission factors that have been reviewed
in publications written since 1985 are assembled and reviewed in this report, in an effort to create
a compilation of the most recent research in this field. The primary focus of this report is,
however, on NH3 emission factors, as opposed to estimates of NH3 emissions Emission estimates
are made for some categories to assist in the determination of the relative importance of various
emission source categories to total NH3 emissions.  The compilation of emission factors presented
in this report updates and adds to the body of emission factors that can be used to produce future
emissions inventories forNH3.

       Ammonia emissions can not be speciated from VOC or PM emissions, because as an
inorganic gaseous chemical, NH3 is not included in VOC emissions estimates, and, as a gas, it is
not included in PM emissions estimates.  Therefore, it is necessary to utilize emission factors for
estimating NH3 emissions.

       Ammonia emissions are important in atmospheric models, because NH3 is the most
important e constituent in the atmospheric boundary layer. The fate of NH3 released from the
ground into the atmosphere is complex and varied, but this NH3 can have a significant effect on
oxidation rates, particularly in clouds, and hence on deposition rates of acidic species. This effect
is predicted not only by models for the heterogeneous chemistry of cloud droplets, but has also
been confirmed by observation and experiment.1 The long  range transport of atmospheric sulfur
dioxide and nitrogen oxide and the products of their reactions have long been studied in relation
to acidic deposition. However, much less research has been done on the effects of atmospheric
NH3, although it is well known that over large areas of Europe acid precipitation is falling, in
which up to 70 percent of the original acid is neutralized by NH3.

       This report presents a narrative on the recent research for the known substantial sources
of NH3 emissions.  Emission factors resulting from this investigation are then compared with the
factors published by National Acid Precipitation Assessment Program (NAPAP), as compiled by
Misenheimer et al. (198V and later by Warn et al. (1990).3 Recommendations on the most
reliable NH emission factors for use in the United States are NH3 emission factors for use in the
United States are made. For each recommended emission factor, a point source classification cod
e (SCC) or area and mobile source (AMS) code is presented, along with an  emission factor rating.

       Recent research on NH3 emissions  as it relates to acid deposition is concentrated in the
European community (specifically, in the Netherlands, Great Britain, and Scandinavia). In
addition, there has been some research conducted in Australia. The majority of the NH3 emissions
studied in current inventories originates from agricultural sources. These agricultural sources are
mainly livestock wastes, with fertilizer applications also providing a significant proportion.  NH3

                                            1- 1

-------
emission estimate numbers vary widely between different studies, but the authors of recent
European inventories all consider animal wastes and fertilizers to be responsible for 90% or more
of the anthropogenic NH3 emissions.  Some of the more recent inventories in Europe even
exclude contributions from industrial facilities entirely, noting that they are insignificant relative to
the agricultural sources.

       Although the European inventories currently focus on agricultural sources, there is
evidence that additional significant sources of NH3 may exist, in a modelling study of acid
deposition, Metcalfe et al (1989)4 suggested that the current estimates of NH3 emissions in the
U.K. were too low to explain the concentrations of ammonium in precipitation and that there may
be other sources of NH3 which have not yet been considered in budget studies (Lee et al, 1992).5
Other research, principally in support of global climate change research, suggests that there may
be significant NH3 emissions from undisturbed soils  and biomass burning.7

       Much of the research obtained and reviewed in this report concerns measurements of NH3,
in which results were generally reported as experimental results rather than as emission factors.
The majority of NH3 emission factors available in the literature are discussed relative to the
development of an emission inventory.  In the development of an emission inventory, emission
factors are often either developed from the experimental measurement literature, or are borrowed
directly from other bodies of work. The primary source for the emission factors reviewed in this
report is the body of recent emission inventory literature. The experimental measurements
literature is also reviewed, to provide  detail on how  the measurements were made. This review
contributes to understanding the uncertainty of the emission factors, addresses  the extent to
which the factors  presented incorporate the most recent research, and identifies  data gaps for
future emission factor development.

       The most recent NH3 inventory prepared in the U.S. is the Emissions Inventory for the
National Particulate Matter Study8 which used Bureau of Economic Activity data to grow the
1985 NAPAP inventory to the 1990 study year.  Other recent studies include the following:
ApSimon et al. (1987) published an inventory for the U.K. for the 1981 study year; Buijisman
(1987)9 published a 1982 inventory of NH3 for Europe the same year; Erisman (1989)10 published
a 1987 and 1988 inventory for the Netherlands;  Moller and Schieferdecker (1989)11 published
NH3 estimates through 1985 for the G.D.R.;  Kruse et al (1989)12 published an updated inventory
for Great Britain;  Denmead (1990)13  published an inventory for Australia; and, finally, the most
recent inventory of Europe was published by Asman (1992),14 and Lee and Longhurst (1993)15
published the most recent inventory for  Great Britain.  Additional inventories have been published
for European countries; however, these -publications were not translated into English and were
not reviewed in this report.

       This report is organized into seven sections.  After this introduction, the next five sections
discuss NH3 emission  factors, and present recommendations for their use. These five sections
address NH3 emissions from animal husbandry, fertilizer application, industrial  sources
                                           1-2

-------
combustion, and miscellaneous categories.  The final section presents the conclusions of this
report and includes recommendations on further research,that will enhance the understanding of
NH3 emissions in the United States.
                                           1-

-------
                           REFERENCES FOR SECTION 1

1.      ApSimon, H.M., M. Kruse, and I.N.B. Bell Ammonia Emissions and 7heir Role in Acid
       Deposition. Atmospheric Environment Volume 21, No. 9:1939-1946. Great Britain.
       1987.

2.      Misenheimer, D.C., T.E. Warn, and S. Zelmanowitz. Ammonia Emission Factors for the
       NAPAP Emission Inventory. EPA-600/7-87-001. U.S. Environmental Protection
       Agency, Office of Research and Development, Washington, DC. January 1987.

3.      Warn, T.E., S. Zelmanowitz, and M. Saeger. Development and Selection of Ammonia
       Emission Factors for the 1985 NAPAP Emissions Inventory. EPA-600/7-90-014.
       Prepared for the National Acid Precipitation Assessment Program (NAPAP) by the U.S.
       Environmental Protection Agency, Office of Research and Development, Washington,
       DC. June 1990.

4.      Metcalf, S.E., Atkins, D.H.F. and Derwent, R.G. Acid deposition modeling and the
       interpretation of the United Kingdom secondary precipitation network data. Atmos,
       Environ. 23. 2033-2052. 1989.

5.      Lee, D.S., P.D. Nason, and S.L. Bennett. Atmospheric Ammonia in the Vicinity of a
       Sewage Treatment Plant - results from a preliminary investigation.  AEA-EE-0328.
       Environmental Physics Group,  Environmental Safety Division, AEA Environment and
       Energy, Harwell Laboratory, Oxfordshire, England. May 1992.

6.      Schlesinger, W.H. and A.E. Hartley. A Global Budgetfor Atmospheric NH3.
       Biogeochemistrv 15:191-211.  Printed in the Netherlands. 1992.

7.      Denmead, O.T. An Ammonia Budgetfor Australia. Australian Journal of Soil Resources
       28, 887-900.  Australia. 1990.

8.      E.H. Pechan & Associates, Inc. F-missions Inventory for the National Particulate Matter
       Study. Final Draft. Prepared for  the U.S. Environmental Protection Agency, Wahsington,
       DC under EPA Contract No. 68-D3005 (Work Assignment No. 0-10). July 1994.

9.      Buijsman, E., H.F.M. Maas, W.A.H. Asman. Anthropogenic NH3 Emissions in Europe.
       Atmospheric Environment. Volume 21, No.5:1009-1022. Great Britain. 1987.

10.     J.W. Erisman.  Ammnonia Emissions in the Netherlands in 1987 and 1988.  National
       Institute of Public Health and Environmental Protection. Bilthoven, The Netherlands.
       July 1989.
                                         1-4

-------
                                     SECTION 2

               AMMONIA EMISSIONS FROM ANIMAL HUSBANDRY

       Ammonia emissions from animal husbandry are a significant portion of total NH3
emissions in recent inventories.  In the 1985 NAPAP inventory, twelve categories of animal
husbandry accounted for over 70 percent of the total NH3 emissions.  In recent studies of NH3
emissions in Europe, animal husbandry accounted for over 80 percent of NH3 emissions.

2.1 SUMMARY OF RECENT RESEARCH IN EUROPE

       Recent NH3 emission factor research in Europe, and specifically in the Netherlands,
has focused primarily on increasing the  accuracy and resolution of NH3 emission factors for
various classes or subcategories of animal husbandry.  Two predominant European NH3
emission inventories have been located in the literature.   The first is a 1982 inventory
developed by Buijsman (1987).l  The work of Buijsman (1987) was followed by a 1987 and
1988 inventory of NH3 emissions in the Netherlands by Erisman (1989).2 Both of these
inventory efforts identified uncertainties in emission factors for various classes of animal
husbandry and resulted in additional field  measurement programs designed to increase the
understanding of NH3 emissions and the effectiveness of various control programs.

       In 1992, a report on the NH3 emissions in Europe was published by Asman (1992).3
This report incorporates research conducted in the Netherlands through about 1990. The
estimates presented by Asman (1992) (for all categories)  are approximately 21% higher than
the estimates  presented by Buijsman (1987), due to the application of different emission
factors and due,  in minor part, to differences in the number of animals.  In our review of the
recent literature,  the emission factors presented by Asman (1992) are the most recent and
accurate emission factors for animal husbandry.  An emission factor manual  for Europe was
developed by van der Most and Veldt in 19924 that utilizes the same emission factors that
are published by Asman (1992) for NH3 emissions from animal husbandry.  Table 2-1  lists
the animal  subcategories and the emission factors developed in the Netherlands.

       Additional work on NH3 emissions from animal husbandry has been conducted by
many researchers in Europe. Specifically, there have been numerous inventories developed
for countries  and regions within Europe and Australia.

       ApSimon et al. (1987)5  and later Kruse et al. (1989)6 developed NH3 emission
inventories from agriculture in Great Britain, using 1981  census of agriculture data. Both
utilized the research conducted by Kruse (1986)7 on NH3 volatilization from  agricultural
sources.  Kruse compared the emission factors that he had generated with the emission factors
used by Buijsman (1987) and noted that they are in agreement. Lee (1993)8 also developed
an NH3 emission inventory for the United Kingdom for the 1987 study year.  The NH3
emissions from animal husbandry in this research effort were based on the factors used by
ApSimon (1987) and Kruse (1989).  These factors were slightly different than the factors that

                                          2-1

-------
TABLE 2-1. ANIMALS OF HUSBANDRY EMISSION FACTORS
             (kg NH3/Animal/Yr) [Asman (1992)]
Animal
Young cattle
Dairy & calf cows
Breeding bulls > 2 yr
Fattening calves
Young cattle for fattening
Fattening/grazing cattle > 2 yr
Fattening pigs
Breeding sows 20-50 kg
Breeding sows > 50 kg
Other sows
Boars > 50 kg
Mature boars
Broilers
Mother animals < 6 mo.
Mother animals > 6 mo.
Laying hens < 18 wks.
Laying hens > 18 wks.
Ducks
Turkeys for slaughter
Turkeys < 7 mo.
Turkeys > 7 mo.
Horses & ponies
Ewes
Milch goats
Stable +
storage
3.87
12.87
10.58
1.6
5.76
0
3.18
2.42
8.09
8.09
3.18
5.52
0.065
0.141
0.315
0.05
0.1
0.117
0.429
0.445
0.639
3.9
0.7
2.3
Spreading
6.34
21.09
17.33
3.63
9.43
0
3.8
2.8
8.04
8.04
3.8
5.48
0.102
0.128
0.283
0.12
0.205
0
0.429
0.445
0.639
3.6
1.28
4.1
Grazing
2.83
5.76
0
0
0
8.22
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4.7
1.39
0
Total
13.04
39.72
27.91
5.23
15.19
8.22
6.98
5.22
16.13
16.13
6.98
11
0.167
0.269
0.598
0.17
0.305
0.117
0.858
0.89
1.278
12.2
3.37
6.4
                          2-2

-------
Buijsman (1987) used to develop a European NH3 inventory.

       Moller (1989)9 developed an NH3 emission inventory in the German Democratic
Republic (G.D.R.).  He based his work on emission factors developed by Auermann and
Meyer (1978)10 and stated that the emission factors are of the same order as the total
emission factors used by Buijsman (1987).

       Denmead (1990)11 developed an NH3 inventory for Australia.  He compared a daily
emission factor developed in Australia for sheep (5.8 and 5.2 g N/sheep) with the value used
by Buijsman et al. (1987) for European sheep (8.5 g N/day).  The work of Denmead is not
referenced in the work of Asman (1992).  This discrepancy in the NH3 emission factor for
sheep is a fairly large  one.  Inventories in areas that have a large sheep population may want
to examine this discrepancy to determine the most applicable factor.

       The inventory developed by Asman (1992) and the NH3 emission factors published by
van der Most (1992) reference the research results of De Winkel (1988)12 and Van der Hoek
(1991).13 Unfortunately, the work of De Winkel (1988) is published only in Dutch and
appears to be a primary reference in terms of describing the research methods and the actual
derivation of the emission factors.

       More recently,  additional studies have been published which are not incorporated into
the Asman (1992) NH3 emission factors. In 1987, four experiments were carried out, during
a period of 3 weeks in May/June, on a cattle and pig farm in The Netherlands.14 Small
wind-tunnels were used to make direct measurements of NH3 volatilization from the different
types of slurry and manure applied to the surface of grassland.  NH3 was collected at the inlet
and outlet of the wind tunnels in absorption flasks containing orthophosphoric acid and
emissions were determined by using a modified Berthelot method, as conducted by Krom
(1980).15

       Kirchmann and Witter (1989) analyzed NH3 volatilization during aerobic and
anaerobic poultry manure decomposition.16   Their analytical method involved the absorption
of NH3 in boric acid and back-titration with carbon dioxide.   Total nitrogen was analyzed
with the regular Kjeldahl method.

2.2 FACTORS INFLUENCING AMMONIA EMISSIONS FROM ANIMAL
HUSBANDRY

       There are several factors that have been shown to influence NH3 emissions from
livestock.  These factors include:

  •     Nitrogen content of the feed and its relative share of different amino acids.
  •     Conversion factor between N in animal  food and N in the meat and in the milk (which
       determines the  amount of N waste available).
  •     Kind of animal and age/weight.


                                          2-3

-------
       Housing system.
  •     The manner in which the manure is stored (pile, open/closed tanks).

       There are  additional NH3 emissions after the spreading of manure. Factors influencing
these emissions include:

       Meteorological/climatological conditions: temperature, turbulence, air humidity and
       precipitation. Emissions generally increase with temperature and turbulence, but
       decrease with air humidity (which slows down the evaporation of water from manure,
       and leads  to a lower concentration of NH3 in the air, if the components are dissolved
       in manure) and during and after precipitation periods.
  •     Irrigation.   If a  field is irrigated, the manure is diluted and  enters the soil at a larger
       rate, both  of which lead to a lower emission.
  •     Properties of the soil (pH, calcium content, water content, buffer capacity and porosity
       etc.).  The emissions generally increase with increasing pH, calcium  content, and
       porosity, but decrease with increasing buffer capacity and water content.
       Properties of the manure (pH, viscosity, content of dry matter).  The emissions
       generally increase with increasing pH,  viscosity and content of dry matter.  A high
       viscosity prevents the manure or fertilizer from entering the soil.
  •     Amount applied per hectare.  The fraction of N in manure which evaporates increases
       with the amount applied.
  •     The way of applying the manure or fertilizer.  If the manure is injected, a much lower
       emission results.
  •     Time between spreading and plowing (for arable land).  The emission is generally
       largest during the first hours after spreading.  Ploughing shortly after spreading can
       reduce the emissions considerably.

       If the animals are grazing in the meadows, the manure is not stored,  but deposited
directly and it is therefore exposed immediately to loss processes other than volatilization of
NH3 to the atmosphere. These processes are uptake by the grass, wetting by precipitation,
leading to dilution and penetration of the soil with diluted manure,  and nitrification.  The NH3
emission rate during the grazing period is, for this reason, less than if the animals were in the
stable, including the contribution during storage and subsequent  spreading.   The total emission
from animals, therefore, depends on the fraction of the time that they are in the meadows.17

2.3   NAPAP EMISSION FACTORS FOR ANIMAL HUSBANDRY

       The NAPAP NH3 emission factor report presented emission factors for twelve
categories of animal husbandry.18  None of the recent research conducted in Europe (in
either the Netherlands or Great Britain) was included in the development of the NAPAP  NH3
emission factors.   In addition, the NAPAP factors were given a quality rating of E (lowest
possible).
                                           2-4

-------
       The 1980 NAPAP emission inventory utilized an NH3 emission factor for beef cattle
feedlots developed in the U.S. in 1911 w  This emission factor is cited in the current
Compilation of Air Pollutant Emission Factors - Volume I (AP-42)20 The  measurement of
NH3 in this study was conducted using 10 ml of dilute  sulfuric acid.  The NH3 concentration
was measured using  nesslerization.  A second study of  NH3 emissions from cattle feedlots
again used sulfuric acid in the collection of NH3, and then used the indophenol method and
GC analysis of a pentafluorobenzamide derivative of NH3 to calculate NH3 emissions.  An
average of these measurements resulted in the point source emission factor from beef cattle
feedlots of 5.9 kg/year/animal (13 Ibs/year/animal).

       The 1980 NAPAP emission inventory utilized a second set of research results  on
manure production and characterization data to develop emission factors for land-spreading of
livestock and poultry manure.  Ammonia content of four types of animal manure (dairy cows,
beef cattle, swine, and poultry) was measured in different waste management systems (fresh,
scraped, slurry, or lagoon).   These data were averaged over the various  livestock groups and
assumptions were made on the relative percentage of solid versus liquid manure that are
surface-applied.  A second  assumption that 75% is surface applied and 25% is injected was
made.  No information was provided in the NAPAP NH3 emission factor reports on the
laboratory methods utilized in this series of research. This analysis resulted in NH3 emission
factors for cropland spreading of livestock manure.

       The 1985 NAPAP emission inventory utilized the beef cattle feedlot emission  factor,
revised the emission  factors for cropland spreading of livestock manure, and developed NH3
emission factors for range animals.  The initial NAPAP NH3 emission factor for cropland
spreading of animal manures was revised to reflect individual NH4-N contents of manure by
livestock category. Previously, an average NH4-N content was used over all animal types.
The factors were also revised to present the emission factors in terms of NH3 emitted per
animal rather that NH4-N. No information on the analytical methods was provided.

       The 1985 NAPAP emission inventory utilized new emission factors for range animals.
The range animal emission factors were developed based on 1978 data on typical stocking
rates and animal weights for four livestock categories (beef cattle, dairy cattle, sheep, and
swine).  Emissions were calculated using the cropland spreading factor for confined animals
and the range emission factor for the unconfmed animals.  With the exception of beef cattle
feedlots, the NH3 emissions during the housing of the animals does not  appear to be
addressed.  For beef cattle and swine, the same  volatilization rates as were used for cropland
spreading were used  for range animals. The value used for dairy cattle was based on three
data points and was judged to be low. No value was provided for sheep so an average of
beef and dairy cattle  was used for sheep.

       The twelve NAPAP emission factors  and the activity data that were utilized in the
development of 1985 emission estimates are presented in Table 2-2. Using the 1985
populations for these animal classes allowed for the development of averages for the four
major categories (cattle, pigs, poultry, and sheep), for comparison with the European research.

                                          2-5

-------
    TABLE 2-2.  1985 NAPAP ANIMAL HUSBANDRY EMISSION FACTORS AND
                              ANIMAL POPULATIONS
Animal Category
Cattle
Beef cattle feedlots
Confined Beef -
spreading
Ranging Beef
Confined Dairy-
spreading
Ranging Dairy
Poultry
Laying hens
Broilers
Turkeys
Ranging Swine
Confined Swine
Ranging Sheep
Confined Sheep
1982 Population8

2.3 x 107
6.5 x 106
2.6 x 107
4.5 x 106
4.9 x 106

2.9 x 108
5.0 x 108
3.9 x 107
4.8 x 106
4.9 x 107
1.0 x 107
1.9 x 106
Emission Factor Emission Factor
(Ibs/animal/yr) (kg/animal/yr)

13.0
1.7
44.4
27.0
45

0.34
0.043
0.29
39
4.3
4.5
1.9

5.90
0.77
20.14
12.25
20.41

0.15
0.02
0.13
17.69
1.95
2.04
0.86
  a The 1985 estimates are based on 1982 population statistics. The split of confined versus unconfmed
  animals is based on 1978 data.
2.4 COMPARISON OF AMMONIA EMISSION FACTORS FOR ANIMAL
HUSBANDRY

       Asman (1992) developed average emission factors by dividing the emission of a
category by the number of animals in that category.  These values were then used for the
calculation of NH3 emissions from animal husbandry for all of Europe.  The relative
contribution of each subcategory to each category for all European countries is the same as
for the Netherlands.  Average factors for the 1985 NAPAP inventory can be derived using the
published 1985 activity or animal population data and emission factors.  Table 2-3 presents
                                         2-6

-------
averages developed from the Dutch data, from the values utilized by Buijsman (1987) and
from the factors published in the NAPAP report.

 TABLE 2-3.  COMPARISON OF ANIMALS OF HUSBANDRY EMISSION FACTORS
                                  (kg NH3/Animal/Yr)
Animal
Cattle
Swine
Poultry
Horses
Sheep
Asman (1992)
Stable +
storage
7.396
2.521"
0.095
3.9
0.381
Spreading
12.244
2.836a
0.154
3.6
0.693
Grazing
3.403
0
0
4.7
0.623
1
Total
23.043
5.357a
0.249
12.2
1.697
Suijsman et
al. (1987)
18.
2.8
0.26
9.4
3.1
NAPAP
(1990)
12.6
3.35
0.071
-
1.85
  These composites appear to have been calculated using the incorrect number of swine in the Netherlands
  and are therefore too low.  The correct values are 4.006, 4.506, and 8.512 respectively.
       As shown in Table 2-3, the NAPAP emission factors, with the exception of sheep, are
significantly lower than the values used by both Asman (1992) and Buijsman (1987). The
emission factor for sheep in the NAPAP inventory was derived from an average NH3
volatilization rate for dairy and beef cattle.

       A manuscript by Lee (1994)21 explores the uncertainties in current NH3 estimates for
the United Kingdom.  This manuscript presents a  comparison of the NH3 animal husbandry
emission factors recently utilized throughout Europe and the U.S.  Table 2-4 presents the
comparison made by Lee (1994).

2.5 ANIMAL HUSBANDRY ACTIVITY  DATA  FOR THE UNITED STATES

       The usefulness of the emission factors presented by Asman (1992) in the development
of an NH3 emission inventory are dependent upon the availability  of supporting activity data.
The U.S. Department of Agriculture (USDA), National Agricultural Statistics Service,
maintains annual records at both the national and  state levels. These statistics are  published
in a variety of reports and numerous spreadsheets  containing raw data are available through
bulletin boards.T The following statistics on  animal  populations were obtained from  an
T The USDA National Agricultural Statistics Service (Washington, DC) has a joint project
with the Albert Mann Library of Cornell University (Ithica, NY) to maintain the Economics
and Statistics system which can be accessed on the internet through the U.S. EPA IBM gopher.

                                          2-7

-------
             TABLE 2-4. EMISSION FACTORS USED IN DIFFERENT EMISSION INVENTORIES
                     FOR ANIMAL SOURCES OF AMMONIA' (kg NH3 as N/Animal/Vear)b
Animal
Beef cattle
Daily cattle
Pigs
Sheep
Laying hens
Broilers
to
00 Turkeys
Horses
Cats
Dogs
NAPAP
0,63
27.0
1.6
0.7
0,12
0.016
0,10
—
--
..
Cass et al.
(1982)
..
27.0
4.5
2.7
0.24
0,24
0.66
33
0.66
1.98
Kruse et al. Jarvis & Pain Asman Buijsman et al. Moller &
(1989) (1990) (1990) (1987) Schieferdecker
(1989)
—
19.31
2.86
2.68
0.233
0,233
0.233
31.6
--
—
_
7.8 20.7
4.35 3.96
0.36 1.57
0,13 0.26
0.13 0.26
0.26
10.3
_
_
—
14.8
2.3
2.5
0.21
0.21
0.21
7.7
—
—
-
22.1
5.2
3.0
0.22
0.22
15.0
„
--
* Lee & DollarJ, 1994
fc To convert the units to kg NH,/Animal/Year, multiply the emission factor by the stoichiometric ratio of N to NHJt 14/17.
' The calculation of the NAPAP average emissioa factors Is uol documenied by Lee (1994).

-------
annual report on agricultural statistics.22

2.5.1  Cattle and Calves

       There are eight readily available classifications for cattle and calves for the U.S. In
1992 there were 100 million cattle and calves.  The eight classifications,  1992 populations,
and the animal classifications currently listed in Asman (1992) are provided in Table 2-5.
Additional statistics on the number of cattle and calves on feedn in the U.S. indicate that in
1992, approximately 12 percent of the total cattle and calves were on feed. Not all of the calf
and cow classifications would have an equal percentage on feed.  Additional information is
needed prior to utilizing  the statistics of cattle and calves on feed to determine the relative
distributions of animals in stable +  storage versus those animals that are grazing.

       As shown in Table 2-5, most of the links between the U.S. agricultural categories for
cattle and calves have a  corresponding category presented by Asman (1992).  The only
exceptions is the category of Heifers, 226.8 kg and over.  It is unclear if the appropriate
category is young cattle, or young cattle for fattening.  The assumption is that young cattle
for fattening applies to beef cow replacements but not to milk cow replacements or other.

       A composite emission factor for cattle and calves is developed using the  1992 cattle
and calves populations.   The composite factor is 22.9 kg NH3/animal.  This factor is very
similar to the composite  factor of 23.043 kg NH3/animal/year developed by Asman (1992) for
use in the European inventories.

2.5.2  Hogs and Pigs

       Preliminary statistics for 1991 indicate there were 57.7 million hogs and pigs in the
United States.  The USDA classifies hogs and pigs into six general categories based primarily
on animal weight.  Table 2-6 lists the  six classifications, 1991 populations, and the animal
classifications currently listed in Asman (1992). Hogs and  pigs are generally not grazing
animals.

       As shown in Table 2-6, the  links between the U.S. agricultural categories and the
emission factor categories presented by Asman (1992) are not clear cut.   Asman (1992)
n  Cattle and calves on feed are animals for slaughter market being fed a full ration of grain
or other concentrates and are expected to produce a carcass that will grade Select or better.

                                           2-9

-------
  TABLE 2-5. U.S. AGRICULTURE ACTIVITY CLASSIFICATION AND EMISSION
                        FACTORS FOR CATTLE AND CALVES
     U.S. Agricultural Statistics
          Classifications
   1992          Emission Factor
 Populations     Classifications Asman
(106 animals)           (1992)
Emission Factor
(kg NH3/animal)
    Cows and heifers that have
    calved (Beef cows)

    Cows and heifers that have
    calved (Milk cows)

    500 pounds and over: Heifers
    - Beef cow replacements

    500 pounds and over: Heifers
    - Milk cow replacements

    500 pounds and over: Heifers
    - Other

    500 pounds and over: Steers
    500 pounds and over: Bulls

    Calves under 500 pounds

    Total
       33.8    Dairy & calf cows


        9.90   Dairy & calf cows


        5.75   Young cattle for
              fattening

        4.20   Young cattle


        8.68   Young cattle


       16.7    Fattening/grazing cattle
              > 2 yr

        2.28   Breeding bulls > 2 yr

       18.7    Fattening Calves

      100.
            39.72
            39.72
            15.19
            13.04
            13.04
            27.91

             5.23
presents two emission factors for sows based on weight.  In the U.S., statistics are presented
for hogs and pigs kept for breeding and sows farrowing.  In 1991, 7.25 million hogs and pigs
were kept for breeding with approximately 6 million sows farrowing. The difference is either
immature sows (i.e. < 50 kg) or male pigs kept for breeding.  A composite emission factor
for hogs and pigs kept for breeding is presented based on the 1991 statistics and the
assumption that the 6  million sows farrowing are breeding sows > 50 kg and the remaining
1.25 million  hogs and pigs kept for breeding are breeding sows 20-50 kg.

       The U.S.  also keeps statistics on market hogs by weight groups.  Asman (1992)
presents three categories but only two emission factors  (fattening pigs and boars> 50 kg have
the same emission factor).  The link between the emission factors and the U.S.  agricultural
statistics assumes that pigs and hogs under 54 kg are fattening pigs and pigs and hogs over 54
kg are mature boars.
                                           2-10

-------
      TABLE 2-6.  U.S. AGRICULTURE ACTIVITY CLASSIFICATIONS AND
                    EMISSION FACTORS FOR HOGS AND PIGS
U.S. Agricultural Statistics 1991
Classifications Populations
(106 animals)
Kept for breeding
Sows farrowing3
Other - kept for breeding15
Market hogs by weight groups
Under 27.2 kilograms
27.3 to 54.0 kilograms
54.1 to 81.2 kilograms
81.3 to 99.3 kilograms and 99.4
kilograms and over
Total

6.02
1.25

18.7
13.0
10.4
8.4
57.7
Emission Factor Emission Factor
Classifications Asman (kg NH3/animal)
(1992)

Breeding sows > 50 kg
Breeding sows 20-50 kg

Fattening pigs
Fattening pigs
Mature boars
Mature boars


16.13
5.22

6.98
6.98
11
11

  aAn average of the sows farrowing in December through May and the sows farrowing in June through
  November.
  bKept for breeding minus sows farrowing.
       A composite emission factor for hogs and pigs is developed using the 1991
populations.  The composite factor is 9.21 kg NH3/animal.  This factor is higher than the
composite factor of 8.512m kg NH3/animal/year developed by Asman (1992) based on the
swine populations in the Netherlands.

2.5.3  Poultry

       Poultry includes chickens, ducks, and turkeys although chickens represent the largest
source of NH3 emissions.  Chickens in the U.S. are classified into hens, pullets, other
chickens and broilers with three subcategories of pullets. It is unclear what the difference is
between hens and pullets.  Asman (1992) presents emission factors for mother animals, laying
hens,  and broilers. It is also unclear what the difference is between mother animals and
laying hens.  Asman (1992) also presents an emission factor for ducks and two factors for
turkeys based on age. The U.S. has statistics on turkeys (with no distinction in age) but does
not keep statistics on ducks.
m  There was a mathematical error in the composites presented by Asman (1992). The value
of 8.512 kg NH3/animal/year was calculated directly from animal populations and emission
factors presented by Asman (1992).

                                         2-11

-------
       Table 2-7 illustrates the readily available agricultural classifications, latest population
estimates, and the link to the emission factors of Asman (1992).  As mentioned above there is
some ambiguity in the distinctions between hens, pullets, mother animals, and laying hens as
used by Asman (1992) and the U.S. Department of Agriculture, however the populations (and
consequently the emissions) of hens and pullets is dwarfed by the population of broilers. A
composite emission factor for chickens was developed based on the links provided in Table 2-
7 and the 1991 population statistics. The  composite emission factor of 0.179 kg
NH3/animal/year is also recommended for use in the other chickens category.

2.5.4 Sheep and Lambs

       There were 10.85  million sheep and lambs in the U.S. in  1991.  The five
classifications for sheep and lambs  in the Agriculture statistics are:

       sheep and lambs on feed
       stock sheep - lambs - ewes
       stock sheep - lambs - wethers and rams
       stock sheep - 1 year and over - ewes
  •     stock sheep - 1 year and over - wethers  and rams

       Asman (1992) presents one  set of emission factors for ewes and these are
recommended for use for all categories of sheep and lambs in the U.S.

2.6  AMMONIA EMISSION FACTORS FOR MISCELLANEOUS ANIMAL
CATEGORIES

       In addition to the  more common animals presented above, emission factors have been
developed for three animal types that  are bred for fur (foxes and mink) or for meat and fur
(rabbits).  These emission factors were estimated by van der Hoek but apparently have not
been published in any  sources other than Erisman (1989).  In addition, Erisman (1989) uses
data developed by Cass (1982)23 to  estimate NH3 emissions from domestic cats and dogs.
The emission factors for these miscellaneous  types of animals are listed in Table 2-8.

       In the USDA agricultural statistics there were 3.27 million mink pelts produced in
1991.  Statistics were not readily available for fox, rabbit, cats or dogs.

2.7  RECOMMENDED  ANIMAL HUSBANDRY EMISSION FACTORS AND SOURCE
CLASSIFICATION CODES

       National inventories developed in the  United States utilize source classification codes
(SCCs) to describe point  source emissions and area and mobile source (AMS) codes to
describe area source emission categories.  Although there are point source SCCs for beef
cattle feedlots, the emission factors  recommended for use in this  section are for area source
categories.

                                         2-12

-------
       TABLE 2-7.  U.S. AGRICULTURE ACTIVITY CLASSIFICATION AND
                         EMISSION FACTORS FOR POULTRY
    U.S. Agricultural Statistics
         Classifications
   1991
 Populations
(106 animals)
     Emission Factor
Classifications Asman (1992)
Emission Factor
(kg NH3/animal)
   Hens

   Pullets - Of laying age

   Pullets - 3 months old and
   older not of laying age

   Pullets - Under 3 months
   old

   Other chickens

   Broilers

   Ducks

   Turkeys
      116     Mother animals > 6 mo.

      162     Laying hens > 18 wk.

       33.5    Mother animals < 6 mo.


       40.8    Laying hens < 18 wk.


        6.85   Composite factor for chickens

     6,138     Broilers

       20.0a   Ducks

     285b     Turkeys for slaughter

              Turkeys < 7 mo.

              Turkeys > 7 mo.
                                       0.598

                                       0.305

                                       0.269


                                       0.17


                                       0.179

                                       0.167

                                       0.117

                                       0.858

                                       0.89

                                       1.278
  aThe number of ducks reported are the number of ducks inspected in 1991.  The number of ducks inspected
  is a conservative estimate and is smaller than the actual population of ducks.
  bThere is no breakdown on the population of turkeys based on age.
       Table 2-9 shows recommended emission factors for animal husbandry.  We have
recommended use of the latest European emission factors (Asman,  1992) for the animal
husbandry categories. The emission factor ratings for Cattle and Calves, Hogs and Pigs, and
Poultry range between B and C. The emission factors presented by Asman (1992) represent a
large body of literature,  however, there are many factors influencing NH3 emissions from
animals and because  many of the primary references are in foreign languages, it is not clear
that the database represents a good cross section of the U.S.  agricultural practices. The
emission factors presented by Asman (1992) are therefore  assigned a B rating.

       The emission  factors presented by Asman (1992) are  linked to animal husbandry
categories reported by the  United States Department of Agriculture.  Although the best
information available was  used to link the emission factors to the activity data, additional
uncertainty is introduced in this process and therefore, some  of the animal husbandry
emission factors are given a rating of C to reflect the uncertainty of the  link. This uncertainty
could be reduced with additional research into the primary references from which the data are
                                           2-13

-------
 TABLE 2-8.  AMMONIA EMISSION FACTORS FOR MISCELLANEOUS ANIMALS
                                (kg NH3/Animal/Year).
Animal
Mink
Foxa
Rabbit
Cats
Dogs
Stable + storage
0.58
2.25
1


Spreading
0
0
1.8


Total
0.58
2.25
2.8
0.83
2.5
    Weighted average for blue-foxes (2/3) and silver foxes (1/3).
extracted.  In addition, there is a large discrepancy in the factor for sheep and lambs that was
presented by Asman (1992) for Europe and the value that was presented by Denmead (1990)
for Australia. Therefore, the emission factor rating for sheep is currently D.

       The emission factors for the miscellaneous animal categories including mink, fox,
rabbit, dogs and cats are all given  an E rating due to the  small size of the data sets used to
derive these factors.
                                         2-14

-------
TABLE 2-9.  RECOMMENDED AMMONIA EMISSION FACTORS FOR ANIMAL HUSBANDRY
Source
(U.S. Agricultural Statistics
Classifications)
Cattle and Calves - Composite
Cows and heifers that have
calved (Beef cows)
Cows and heifers that have
calved (Milk cows)
226.8 kg (500 pounds) and over:
Heifers - Beef cow replacements
226.8 kg (500 pounds) and over:
Heifers - Milk cow replacements
226.8 kg (500 pounds) and over:
Heifers - Other
226.8 kg (500 pounds) and over:
Steers
226.8 kg (500 pounds) and over:
Bulls
Calves under 226.8 kg (500
pounds)
Hogs and Pigs - Composite
Kept for breeding
Sows farrowing
Other - kept for breeding
Market hogs by weight groups
Under 27.2 kg (60 pounds)
27.2 to 54.0 kg (60 to 119
pounds)
AMS 1991 Emission Factor Emission Factor
Classification Populations Classifications (kg NH3/animal)
Codes (106 animals) (Asman, 1992)
28-05-020-000
28-05-020-001
28-05-020-002
28-05-020-003
28-05-020-004
28-05-020-005
28-05-020-006
28-05-020-007
28-05-020-008
28-05-025-000
28-05-025-010
28-05-025-011
28-05-025-012
28-05-025-020
28-05-025-021
28-05-025-022
100
33.8
9.90
5.75
4.20
8.68
16.7
2.28
18.7
57.75
7.25
6.02
1.23

18.7
13.0

Dairy & calf cows
Dairy & calf cows
Young cattle for fattening
Young cattle
Young cattle
Fattening/grazing cattle >
2yr
Breeding bulls > 2 yr
Fattening Calves


Breeding sows > 50 kg.
Breeding sows 20-50 kg

Fattening pigs
Fattening pigs
22.9
39.72
39.72
15.19
13.04
13.04
8.22
27.91
5.23
9.21

16.13
5.22

6.98
6.98
Factor
Rating
B
B
B
B
C
B
C
C
B
B

B
C

B
C
Emission Factor
(Ib NH3/animal)
50.5
87.57
87.57
33.49
28.75
28.75
18.12
61.53
11.53
20.30

35.56
11.5

15.4
15.4
Estimated
emissions
(Gg/year)
2,290
1,342
393
87
55
113
137
64
98
531

97.1
6.52

131
90.7
                                  (Continued)

-------
TABLE 2-9 (Continued)
Source
(U.S. Agricultural Statistics
Classifications)
54.1 to 81.2 kg (120 to 179
pounds)
81.3 to 99.3 kg and 99.4 kg (180
pounds) and over
Poultry - Chickens - Composite
Hens
Pullets - Of laying age
Pullets - 3 months old and older
not of laying age
Pullets - Under 3 months old
Other chickens
Broilers
Poultry - Other
Ducks
Turkeys
Young turkeys
Old turkey
Fryer-roasted turkey
Sheep and Lambs - Composite
Sheep and lambs on feed
Stock sheep-lambs-ewes
Stock sheep-lambs-wethers and
rams
Stock sheep- 1 yr. and over-
ewes
AMS 1991 Emission Factor Emission Factor
Classification Populations Classifications (kg NH3/animal)
Codes (106 animals) (Asman, 1992)
28-05-025-023
28-05-025-024
28-05-030-000
28-05-030-001
28-05-030-002
28-05-030-003
28-05-030-004
28-05-030-005
28-05-030-006
28-05-035-000
28-05-035-001
28-05-035-002
28-05-035-003
28-05-035-004
28-05-035-005
28-05-040-000
28-05-040-001
28-05-040-002
28-05-040-003
28-05-040-004
10.4
8.4
6,497
116
162
33.5
40.8
6.85
6,138

20.0
285



10.85




Mature boars
Mature boars

Mother animals > 6 mo.
Laying hens > 1 8 wk.
Mother animals < 6 mo.
Laying hens < 18 wk.

Broilers

Ducks
Turkeys for slaughter
Turkeys < 7 mo.
Turkeys > 7 mo.
Turkeys for slaughter
Ewes
Ewes
Ewes
Ewes
Ewes
11
11
.1787
0.598
0.305
0.269
0.17
0.179
0.167

0.117
0.858
0.89
1.278
0.858
3.37
3.37
3.37
3.37
3.37
Factor
Rating
B
B
B
B
B
C
B
C
B

B
B
B
B
C
D
D
D
D
D
Emission Factor
(Ib NH3/animal)
24.3
24.3

1.32
.672
.593
.375
.395
.368

.258
1.89
1.96
2.82
1.89
7.43




Estimated
emissions
(Gg/year)
114
92
1,161
69.4
49.4
9.01
6.94
1.23
1,025
247.3
2.34
245



36.56




     (Continued)

-------
TABLE 2-9 (Continued)
Source
(U.S. Agricultural Statistics
Classifications)
Stock sheep- 1 yr. and over-
wethers and rams
Miscellaneous Farm Animals
Goats
Mink
Fox
Rabbit
Miscellaneous Domestic Animals
Cats
Dogs
Horses
AMS 1991
Classification Populations
Codes (106 animals)
28-05-040-005
28-05-045-000
28-05-045-001
28-05-045-002 3.27
28-05-045-003
28-05-045-004
27-10-020-000
27-10-020-010
27-10-020-020
27-10-020-030
Emission Factor
Classifications
(Asman, 1992)
Ewes

Milch goats
Mink
Fox
Rabbit

Cats
Dogs
Horses & ponies
Emission Factor
(kg NH3/animal)
3.37

6.4
0.58
2.25
2.8

0.83
2.5
12.2
Factor
Rating
D

E
E
E
E

E
E
E
Emission Factor
(Ib NH3/animal)


14.1
1.28
4.96
6.2

1.83
5.5
26.9
Estimated
emissions
(Gg/year)



1.90







-------
                        REFERENCES FOR SECTION 2

1.     Buijsman, E., H.F.M. Maas, W.A.H. Asman.  Anthropogenic NH3 Emissions in
      Europe.  Atmospheric Environment, Volume 21, No.5:1009-1022.  Great Britain.
      1987.

2.     J.W. Erisman. Ammonia Emissions in the Netherlands in 1987 and 1988. National
      Institute of Public Health and Environmental Protection. Bilthoven, The Netherlands.
      July 1989.

3.     Asman, Willem A.H. Ammonia Emissions in Europe:  Updated Emission and
      Emission Variations.  National Institute of Public Health and Environmental
      Protection.  Bilthoven, The Netherlands. May 1992.

4.     van der Most, P.F.J. and C. Veldt. Emission Factors Manual PARCOM-ATMOS
      Emission Factors for Air Pollutants 1992. TNO Environmental and Energy Research.
      Reference Number 92-235. Sponsored by the Netherlands, Ministry of Housing,
      Physical Planning,  and the Environment, Air and Energy Directorate Ministry of
      Transport and Water Management. September 1992.

5.    ApSimon,  H.M.,  M. Kruse, and  J.N.B.  Bell.   Ammonia  Emissions
      and  Their Role  in Acid Deposition.   Atmospheric Environment,
      Volume 21,  No.  9:1939-1946.   Great  Britain.  1987

6.     Kruse, M., H.M. ApSimon, and J.N.B. Bell.  Validity and Uncertainty in the
      Calculation of an Emission Inventory for Ammonia Arising from Agriculture in Great
      Britain. Environmental Pollution, Volume 56:237-257. Great Britain.  1989.

7.     Kruse, M. Ammonia Volatilization from Agricultural Sources and their Implication for
      Acid Deposition. MSC-Thesis University of London.  1986.

8.     Lee, D.S., and J.W.S. Longhurst. Estimates of Emissions of SO2, NOX, HCl and NH3
      from a Densely Populated Region of the UK.  Environmental Pollution, Volume 79:37-
      44.  1993.

9.     Moller, D., and H.  Schieferdecker. Ammonia Emission and Deposition ofNHx in the
      G.D.R.  Atmospheric Environment, Volume 23, No. 6:1187-1193.  Great Britain.
      1989.

10.   Auermann  E.  and Meyer R.   Erfassung und hygienische
      Beurteilung von Schadstoffen  in der Umgebung von GroBanlagen
      industrieller Viehhautung.   Research report  (unpubl.)
      Hygienic  Institute  Karl-Marx-Stadt  (G.D.R.).   1978.

11.   Denmead,  O.T.   An Ammonia  Budget for Australia.   Australian
      Journal of Soil Resources.   28:87-900.   Australia.   1990.
                                     2-18

-------
12.   De Winkel K. (1988). Ammoniak-emissiefactor en voor de veehouderij (Emission
     factors for ammonia from livestock, In Dutch). Report Lucht-76, Ministry of Housing,
     Physical Planning and Environment, Leidschendam, The Netherlands. 1988.

13.   Van der Hoek, K.W. Emission factors for ammonia in The Netherlands. Paper
     presented at the "Workshop on Ammonia Emissions in Europe: Emission Factors and
     Abatement costs, HAS A, Luxemburg, Austria. February 4-6, 1991.

14.   Lockyer, D.R., B.F. Pain, and J.V. Klarenbeek. Ammonia Emissions From Cattle, Pig
     and Poultry Wastes Applied to Pasture. Environmental Pollution, Volume 56:19-30.
     Great Britain. 1989.

15.  Krom,  M.D.   Spectrophotometric determination of ammonia:   A
     study  of a modified  Berthelot reaction using salicylate  and
     dichloroisocyanurate.   Analyst, 105,  305-16.   1980.

16.  Kirchmann H., and E.  Witter.   Ammonia volatilization during
     aerobic and anaerobic manure decomposition.   Plant and Soil
     115, 35-41.   Kluwer  Academic Publishers.   Printed in the
     Netherlands.   1989.

17.   Asman (1992). pps. 3-4.

18.  Warn,  T.E.,  S. Zelmanowitz, and M. Saeger.  Development  and
     Selection of Ammonia Emission Factors for the 1985 NAPAP
     Emissions Inventory.  EPA-600/7-90-014.   Prepared by the
     U.S. Environmental Protection Agency,  Washington, DC for the
     National Acid Precipitation Assessment  Program.  June 1990.

19.  Misenheimer,  B.C., T.E.  Warn,  and S.  Zelmanowitz.  Ammonia
     Emission Factors for the NAPAP Emission Inventory.  EPA-
     600/7-87-001.  Prepared by the U.S. Environmental Protection
     Agency,  Washington DC for the National  Acid  Precipitation
     Assessment Program.   January 1987.

20.  U.S. Environmental Protection Agency.   Compilation of Air
     Pollutant Emission Factors - Volume I:  Stationary Point  and
     Area Sources.  AP-42  (GPO 055-000-00251-7).   Fifth Edition.
     U.S. Environmental Protection Agency,  Research Triangle
     Park,  North Carolina.   July 1994.

21.  Lee, D.S,  and G.J. Bollard.  Uncertainties in Current
     Estimates of Emissions  of Ammonia in  the  United Kingdom.
     Accepted for publication in Environmental  Pollution.  1994

22.  United States Department of Agriculture.   Agricultural
     Statistics 1992.  United States Government Printing Office,
     Washington.   1992.
                                 2-19

-------
23.    Cass, G.R., S. Gharib, M. Peterson, and J.W. Tilden.  The origin of ammonia
       emissions to the atmosphere in an urban area.  Open File Report 82-6.
       Environmental Quality Laboratory. California Institute of Technology.  1982.
                                         2-20

-------
                                      SECTION 3

            AMMONIA EMISSIONS FROM FERTILIZER APPLICATION
       Nitrogen fertilizers are extremely important to agriculture in the United States.  Of the
49 million tons of commercial fertilizer consumed in the U.S. in 1993, 39 million tons
contained nitrogen, either as a single nutrient, or mixed with other nutrients such as
phosphorus and potassium.  The total nitrogen content of U.S. fertilizers in 1993 was about
8 Teragrams.1 Many different chemical compounds are used to provide nitrogen in fertilizer,
including ammonia, urea ((NH2)2CO), ammonium nitrate (NH4NO3), mono- and di-ammonium
phosphates ((NH4)H2PO4 and (NH4)2HPO4), ammonium sulfate ((NH4)SO4), ammonium
thiosulfate ((NH4)HSO4), potassium nitrate (KNO3), calcium nitrate (Ca(NO3)2), and sodium
nitrate (NaNO3).  Table 3-1 summarizes the national application rates and nitrogen contents
for different nitrogen fertilizers.

       Most of the compounds listed in Table 3-1 (with the exception of potassium nitrate,
calcium nitrate, and sodium nitrate) can decompose to release NH3 after they are applied to
croplands.  This is commonly termed "ammonia volatilization,"  and is quantified based on the
percentage of nitrogen  in the applied fertilizer that is lost to the air in the form of NH3.   In
the case of urea, NH3 volatilization can be a significant economic concern.2 Nitrogen losses
of 50 percent and more can occur with improper application conditions.

       The 1985 NAPAP emissions inventory addressed NH3 volatilization from only one
type of nitrogen fertilizer, anhydrous NH3.3 Thus NH3 emissions from fertilizer application
accounted for only 46,382 Mg, or about 3 percent of 1985 NAPAP NH3 emissions.  In
contrast,  volatilization from fertilizer application accounts for  about 17 percent of NH3
emissions in recent European NH3  emission inventories.4  The following sections discuss the
emission factors used in Europe, as well as recent research on NH3 volatilization in the U.S.
and Europe.

3.1 EUROPEAN EMISSION FACTORS

       Buijsman et al of the Netherlands, prepared a detailed  NH3 emission inventory for
Europe in 1986 (published in 1987), which included emissions from the application of most
major nitrogen fertilizers.5 Ammonia volatilization factors for these fertilizers were deduced
from several sources, published in  the 1970's and early 1980's.  Sources used by Buijsman et
al (1987) included Terman (1979),6 Fenn and Kissel (1974),7 Fenn et al (1981),8 Fenn and
Miyamoto (1981),9 the U.S. National Research Council (1978),10 Forster and Lippold
(1975),11 Cass et al (1982),12 Bottger et al (1978),13 Slemr and Seller (1984),14 and
Sanders (1980).15

       Another detailed NH3 emission inventory for Europe was prepared by Asman (1992) at
the Netherlands' National Institute  for Public  Health and Environmental Protection.  Asman

                                           3-1

-------
         TABLE 3-1.  SUMMARY OF U.S. NITROGEN FERTILIZER USAGE

Anhydrous ammonia
Aqua ammonia
Nitrogen solutions
Urea
Ammonium nitrate
Ammonium sulfate
Ammonium thiosulfate
Potassium nitrate
Calcium nitrate
Sodium nitrate
Other straight nitrogen
Ammonium phosphates
N-P-Ka
Total
Fertilizer consumed,
year ending 6/30/93
(Mg)
3,593,380
271,288
7,162,419
3,247,631
1,582,039
718,400
156,047
702,378
70,659
43,993
944,803
5,813,042
8,191,414
32,497,492
Nitrogen content
(weight percent)
82.0
20.4
33.9
45.9
33.9
21.0
12.0
15.1
13.7
16.0
20.0
15.5
11.2
30.0
Total N
content
(Mg)
2,946,572
55,343
2,428,060
1,490,663
536,310
150,864
18,726
106,059
9,680
7,039
188,960
901,022
917,439
9,756,736
   aNitrogen(N)-phosphorus(P)-potassium(K) mixtures.
updated Buijsman's emission factors for fertilizer application using more recent laboratory
measurements by Whitehead and Raistrick (1990).16 These updated factors were also
included in the Netherlands' 1992 Emission Factors Manual.17  Asman's factors are
generally somewhat lower than the factors used by Buijsman.

       Table 3-2 summarizes the NH3 emission factors adopted by Buijsman (1987), and later
adopted by Asman (1992) for fertilizer application. For comparison, the NAPAP emission
factor for anhydrous NH3 is also presented.3
                                         3-2

-------
 TABLE 3-2.  SUMMARY OF EUROPEAN EMISSION FACTORS FOR FERTILIZER
                                    APPLICATION
                                           Emission factors (kg NH3/Mg nitrogen)

Anhydrous ammonia
Aqua ammonia
Nitrogen solutions
Urea
Ammonium nitrate
Ammonium sulfate
Ammonium thiosulfate
Other straight nitrogen
N-P-K
Ammonium phosphates
Buij sman
(1987)a
121
121
b
121
121
182
b
b
12
60
Asman
(1992)a
12
12
30
187
25
97
30
30
48
48
NAPAP
(1990)
12
b
b
b
b
b
b
b
b
b
   aBuijsman and Asman expressed ammonia volatilization in terms of percent, or grams
   of nitrogen emitted as ammonia per 100 grams of nitrogen in the fertilizer.
   bNo emission factor was used for the noted category.
3.2 RECENT VOLATILIZATION RESEARCH

       A good deal of research on NH3 volatilization has been carried out since the
development of the European emission factors discussed above.  This research is motivated
mainly by the economic impact of the NH3 losses, with a focus on application parameters that
might aggravate or reduce potential volatilization losses.  Table 3-3 summarizes the results of
recent volatilization studies.  For each study, the table gives the lowest measured NH3
volatilization rate (expressed in terms of mole-percent of nitrogen), the highest measured rate,
and the average for the study.  The average value is  also converted to an emission factor, in
kilograms of NH3 per Megagram of nitrogen in the fertilizer.

       Table 3-3 also gives the applicable European  emission factors for comparison.  In
compiling the volatilization studies, we have focused on tests carried out since 1985.  The
European emission factor work (carried out in 1986 and 1992) included a fairly  thorough
survey of prior work.


                                          3-3

-------
    TABLE 3-3.  SUMMARY OF  RECENT MEASUREMENTS OF AMMONIA
                       VOLATILIZATION FROM FERTILIZER
Study
UB
Aft
JiA
Eur
Tes
Tes
Tes
opean Emission Factors3
Buijsman (1987)
Asman (1992)
t results - urea on soil
Shahandeh et al (1992)
Watson et al (1992)
Watson et al (1992)
Al-Kanani, etal( 1991)
Ali and Stroehlein (1991)
Ali and Stroehlein (1991)
Ismail, et al (1991)
BurchandFox (1989)
Burch and Fox (1989)
Mclnnes, et al (1986)
Average
Conditions





Solution, lab
Solution, field
Solid, field
Solution, lab
Solution, lab
Solid, lab
Solution, lab
Solid, field
Solid, lab
Solution, field

t results - urea mixtures on soil
Ali and Stroehlein (1991)
Al-Kanani, et al ( 1991)
Al-Kanani and MacKenzie (1991)
Average for UANb
UPb solution, lab
UANb solution, lab
UANb solution, field

t results - urea on flooded paddies
DeDatta, et al (1991)
Bouldinetal(1991)
Average
/MONIUM SULFATE
Eur
Tes
opean Emission Factors
Buijsman (1987)
Asman (1992)
t Results
Shahandeh et al (1992)
Jayaweera and Mikkelson (1990)
Burch and Fox (1989)c
Field
Lab






Solution on soil, lab
Flooded paddy, lab
Solid on soil, field
Percent of nitrogen lost as NH3
Minimum


na
na

13
4.7
3.4
2.8
1.5
2.3
0
4.5
18
4


0.83
0.3
2


46
4



na
na

0.2
9
14
Maximum


na
na

19
12
9.1
55
23
17
59
40
31
17


3.3
19
8.5


54
40



na
na

1
50
17
Average


10.0
15.0

16.1
8.5
5.6
30.8
6.7
6.7
9.4
19.5
24.5
11.0
13.9

1.0
10.7
5.0
7.9

50.0
20.0
35.0


15.0
8.0

0.6
15.5
15.0
Average
emission
factor
(kg/Mg N)


122
182

196
103
68
374
82
82
114
237
298
134
169

12
130
61
95

607
243
425


182


8
188
182
The emission factors presented by Buijsman and Asman are based on data gathered through about 1985, and
therefore do not incorporate the test results presented in the balance of this table.
bUP = Urea phosphoric acid, UAN = urea-ammonium nitrate.
bHigher than expected, may be due to dust erosion.
                                              3-4

-------
3.2.1  Urea Applied to Soils

       As Table 3-3 shows, urea has been a particular focus of research, because it is more
susceptible to NH3 volatilization than are other fertilizers.  It is also the largest volume and
fastest growing nitrogen fertilizer worldwide, with consumption increasing at 5 to 6 percent
per year (Bock & Kissel,  1988).  We identified seven recent studies of NH3 losses from urea
applied to soils. Some of these used urea in solution form, some used solid urea, and some
assessed both solutions and solids.

       These studies showed a substantial variability in NH3 volatilization, with NH3 nitrogen
losses ranging from 0 to 60 percent.  On average, the studies show a nitrogen volatilization
rate of about 14 percent.  (That is,  14 percent of the nitrogen in the urea is lost to the air as
NH3.)  This agrees well with the  1992 European  emission factor of 15 percent.

       The urea studies in Table  3-3 quantified impacts of several  parameters on the NH3
volatilization rate.  These parameters include soil moisture content, pH, soil carbonate content,
temperature,  and depth of tilling,  with the specific parameters varying from study to study.
The most consistent findings were related to soil  moisture content.   Al-Kanani et al (1991),18
Ismail  et al (1991),19 Burch and Fox (1989),20 and Mclnnes et a/21 all showed increases in
NH3 volatilization with increased soil moisture content. High soil moisture enhances the
hydrolysis of urea ((NH2)2CO)  to ammonium carbonate ((NH4)2CO3), which can evaporate  as
NH3 and carbon dioxide.

       Ismail et al (1991) developed a multiple regression model relating NH3 volatilization
from urea to soil temperature, pH, urea application rate, and depth  of tilling.  The model is as
follows:

       ER = exp[ -0.935  - 0.0417 T + 0.57 pH + 0.00367 R + 0.178 MC - 0.445  D
              + 0.00154 T2 - 0.00739 (MC)2 + 0.0285 D2 - 0.000378 (R)(D)] - 11

where:        ER =  NH3 emissions (kilograms NH3 per hectare per fertilizer application)

               T =  soil temperature (°C)

             MC =  initial soil moisture content (percent by weight)

              pH =  soil pH

               R =  rate of fertilizer application (kg nitrogen per hectare per application)

               D =  application  depth (centimeters)
                                           3-5

-------
The Tennessee Valley Authority (Bock & Kissel,  1988), and Rachhpal and Nye22'23 have
also both developed computer models of NH3 volatilization from urea applied to soils.

       The studies of pure urea show no significant difference between urea applied in solid
form (with 14.1 percent nitrogen loss) and urea applied as solution (13.7 percent).  In
addition, two studies of urea-ammonium nitrate (UAN) solutions applied to  soils (Al-Kanani
et al [1991], and Al-Kanani  and MacKenzie [1991]24) gave an average NH3 loss close to that
of pure urea.   However, Ali  and Stroehlein (1991) found that mixing urea with phosphoric
acid substantially reduced NH3 emissions by reducing pH and slowing urea  hydrolysis.25

       The sampling and analytical methods used to quantify NH3 losses varied somewhat.
Most of the investigators studied NH3 emissions from soil placed in a container under
controlled laboratory conditions. The containers were generally swept with  clean, moist air at
a controlled rate.  Other investigators studied emissions in the field under various conditions.

       Watson (1992)26 made field tests using  an  emission isolation flux chamber.
Ammonia vapors in the flux chamber outlet were  captured in a phosphoric acid (H3PO4)
impinger, and NH3 concentrations were quantified using flow injection. Mclnnes et al (1986)
made field tests without using an isolation chamber.  In this case, the atmospheric NH3
concentration and wind speed were measured at several heights above the soil. The NH3 flux
was determined by mass transfer calculations using a vertical concentration  gradient.
Ammonia in the ambient air was captured  in a sulfuric acid (H2SO4) impinger and was
quantified using colorimetry.

       Ali and Strohlein (1991) made laboratory tests, capturing NH3 vapors in a sulfuric acid
impinger, and analyzing the  NH3 concentration by using a micro-Kjeldahl distillation
procedure.  The flowrate through the soil container was 15 volume changes per hour.  Al-
Kanani et al (1991), Ismail et al (1991), and Burch  and Fox (1989)  all used similar analytical
procedures for laboratory soil containers. Ammonia vapors were captured in boric acid
(H3BO3) impingers, and NH3 concentrations were  quantified by back-titration with sulfuric
acid (H2SO4).  The container purge rates varied, with Al-Kanani operating at 30 air changes
per minute, Ismail at 15 changes per minute, and  Burch and Fox at 20 changes per minute.
However, all  of these purge  rates are high  enough so that NH3 build-up in the sample
container would not have been a rate limiting factor.

       Shahandeh (1992)27 captured NH3 vapor in a polyurethane sponge  soaked in a
phosphoric acid, glycerine solution; and quantified the NH3 concentration using colorimetry.
In these experiments, the sponge was placed in the lid of a container of soil, with no  forced
air flow through the container.

       In general, the sponge capture technique with no forced air flow (Shahandeh) would
probably result in lower measured NH3 emissions  than the forced flow techniques.  In
addition, O'Halloran (1993)28 compared boric acid impingers with sulfuric acid impingers,
and concluded that the boric acid appeared to trap less NH3. However, these differences

                                          3-6

-------
between capture techniques appear to be small in comparison with the variations caused by
other parameters,  such as soil moisture and soil pH.

3.2.2 Urea Applied to Flooded Paddies

       DeDatta et al (1991)29 measured NH3 emissions from urea applied to flooded rice
paddies.  He measured NH3 concentrations and wind speeds at different heights above the
paddy, and calculated NH3 flux from the vertical  concentration gradient.  Bouldin et al
(1991)30 compiled NH3 emissions data from previous studies of urea used on rice paddies.
DeDatta and Bouldin found average volatilization rates of 20 to 50 percent, which are
substantially higher than rates for urea applied to unflooded soils.

3.2.3 Ammonium  Sulfate

       Three recent studies addressed NH3 volatilization from ammonium sulfate.
Shahandeh et al (1992) studied ammonium  sulfate solution applied to soil in the laboratory
and obtained  a very low NH3 volatilization  rate.  Only about 1 percent of the nitrogen was
volatilized when the ammonium sulfate solution was applied. Shahandeh technique (discussed
further under "Urea Applied to  Soil") involved capturing NH3 in a saturated sponge, with no
forced air flow through the soil container.  The low measured emission rate may in  some part
be due to  the absence of air flow in the container.

       Burch and Fox (1989)21  found a substantially higher rate, about 15 percent, in a field
study.  However,  they indicated that this loss was higher than expected and may be at least
partially attributable to wind erosion.

       Jayaweera and Mikkelson (1990)31 developed a mathematical model of NH3
emissions from  a  flooded paddy treated with ammonium sulfate.  The model took into
account pH, temperature,  application rate, and wind speed.  The predicted loss rate under
typical conditions was about 15.5 percent of the applied nitrogen.

       The average of the rates determined in the studies by Shahandeh, Burch and Fox, and
Jayaweera and Mikkelson agrees reasonably well with the emission factor used by Asman
(1992).  However, the variability among the three studies is so large that any conclusion is
uncertain.

3.3  SUMMARY OF PARAMETERS AFFECTING AMMONIA EMISSIONS

       In  both the European inventory efforts described above, the investigators noted a high
level of variability in NH3 emissions from fertilizer application. Emission measurements
made since the compilation of these inventories continue to exhibit this variability (Table 3-
3).  Emissions depend on several parameters in a complex  manner; however, some general
correlations can be drawn:5'6
                                          3-7

-------
  •     Under comparable circumstances, NH3 emissions from ammonium (NH4+) fertilizers
       can be ranked as follows:  ammonium sulfate > ammonium nitrate > ammonium
       phosphate6

  •     Ammonia losses increase with increasing pH, but decrease with increasing soil cation
       exchange capacity6

       Ammonia losses are reduced if the fertilizers are incorporated into the soil, with the
       exception  of urea.  This is because urea must be hydrolyzed before NH3 is released.
       The hydrolysis reaction generally depends on the enzyme urease, which is found in
       organic matter in the soil.5'6

  •     For acid soils, irrigation or rain following fertilizer application generally reduces NH3
       losses.  Again, the situation is somewhat more complex for urea, because increased
       soil moisture  promotes hydrolysis, which increases NH3 emissions from urea based
       fertilizers.

  •     Ammonia losses are higher when soil with a high moisture content is subjected to
       "drying conditions," such as wind or high temperatures.

3.4 AVAILABILITY OF ACTIVITY DATA

       Information on the application of nitrogen fertilizers is routinely compiled by a
number of groups, because of the importance of these fertilizers to agriculture  in the U.S. and
in the world as a whole.  Table 3-4 summarizes available activity data.  The Tennessee
Valley Authority  compiles detailed annual,  State-level data on the application of nitrogen
fertilizers.1 The U.S. Department of Agriculture compiles similar data.

       The Census of Agriculture compiles county-level data on total agricultural chemical
usage,  and on the acreage devoted to various crops.32  Many agricultural States compile
county data on the application of specific fertilizers, including nitrogen fertilizers.  Some
States also compile data on fertilizer application by month.33

3.5 RECOMMENDED NH3 EMISSION FACTORS

       Table 3-5  shows recommended NH3 emission factors for fertilizer application. For
comparison, the NAPAP emission factor for anhydrous NH3 is also presented.  In addition,
the latest available national activities are given and  annual NH3 emissions are estimated.
Total annual NH3 emissions from fertilizer application are estimated at over 550,000 Mg.

       We have recommended use of the latest European emission factors (Asman,  1992) for
all nitrogen fertilizers. As noted above, extensive recent measurements of NH3 emissions
from urea application yield essentially no change from the latest European factor. For
ammonium sulfate, the results of recent measurements were too widely varied  to draw any

                                           3-8

-------
   TABLE 3-4.  ACTIVITY DATA AVAILABLE FOR FERTILIZER APPLICATION
Source
TVA, and U.S.
Department of Agriculture
Census of Agriculture
State Agriculture
Departments
Information available
Application rates for individual nitrogen
fertilizers
Overall agricultural chemical usage
Acreage devoted to individual crops
Application rates for individual nitrogen
fertilizers
Overall fertilizer application (temporal
information)
Spatial
resolution
State
County
County
County
State
Temporal
resolution
Annual
na
na
Annual
Month
firm conclusions.  For the remaining nitrogen fertilizers, no recent studies were identified to
update or improve on the European  factors.

       The emission factor for urea application is assigned a quality rating of "B."  The data
base for urea is large, but because of the high degree of variability it is not clear that it
represents a good cross section of the source category. The emission factors  for other
nitrogen fertilizers are ranked "C," in that the database consists of a few good sources [the
two European compilations by (Asman, 1992) and (Buijsman, 1987)].

       In addition to the  emission factors given in Table 3-5, a number of models have been
developed for NH3 losses from urea fertilizer. These relate NH3 losses to parameters such as
soil temperature, pH, application rate, and depth of tilling.  One of these  models, a multiple
regression model by Ismail et al (1991), has been reproduced in Section 3.2.1.  In addition,
the Tennessee Valley Authority (Bock & Kissel,  1988), and Rachhpal and Nye  (1986 & 1991)
have both developed computer models of NH3 volatilization from urea  applied to  soils.
                                          3-9

-------
   TABLE 3-5.  RECOMMENDED AMMONIA EMISSION FACTORS FROM
                         FERTILIZER APPLICATION
Description
Anhydrous ammonia
Aqua ammonia
Nitrogen solutions
Urea
Ammonium nitrate
Ammonium sulfate
Ammonium
thiosulfate
Other straight
nitrogen
Ammonium
phosphates
N-P-Kb
Total
AMS code
28-01-700-001
28-01-700-002
28-01-700-003
28-01-700-004
28-01-700-005
28-01-700-006
28-01-700-007
28-01-700-008
28-01-700-009
28-01-700-010

Emission
factor
(kg NH3/Mg N)
12
12
30
182
25
97
30
30
48
48

Factor
rating
C
C
C
B
C
C
C
C
C
C

Emission
factor
(Ib NH3/ton N)
24
24
61
364
49
194
61
61
97
97

Estimated
annual
emissions
(Mg)
35,353
664
74,042
271,250
13,137
14,631
571
5,763
44,487
43,692
503,590
aNo factor was developed for the noted category.
bNitrogen(N)-phosphorus(P)-potassium(K) mixtures.
                                      3-10

-------
                          REFERENCES FOR SECTION 3

1.      Berry, Janice T. and Melanie H. Montgomery.  Commercial Fertilizers 1993.
       Tennessee Valley Authority, National Fertilizer and Environmental Research Center,
       Muscle Shoals, Alabama.  December 1993.

2.      Bock, B.R. and D.E. Kissel (eds.).  Ammonia Volatilization from Urea Fertilizers.
       Bulletin Y-206.  Tennessee Valley Authority, National Fertilizer Development Center,
       Muscle Shoals, Alabama.  1988.

3.      Warn, T.E., S. Zelmanowitz, and M. Saeger.  Development and Selection of Ammonia
       Emission Factors for the 1985 NAPAP Emissions Inventory.  EPA-600/7-90-014, U.S.
       Environmental Protection Agency, Research Triangle Park, North Carolina.  June
       1990.  pg. 30.

4.      Asman, Willem A.H. Ammonia emission in Europe:  Updated emission and emission
       variations. Report No. 228471008.  National Institute for Public Health and
       Environmental Protection, Biltoven.  May 1992.

5.      Buijsman, E., H.F.M. Maas, W.A.H. Asman.  Anthropogenic NH3 Emissions in
       Europe.  Atmospheric Environment, 21:5.  pp 1009-1022. Great Britain.  1987.

6.      Terman, G.L.  Volatilization losses of nitrogen as ammonia from surface-applied
      fertilizers, organic amendments, and crop residues.  Adv. Agronomy 31:189-223.
       1979.

7.      Fenn, L.B. and D.E. Kissel.  Ammonia volatilization from surface applications of
       ammonium compounds on calcareous soils - II. Effects of temperature and rate of
       ammonium nitrogen application.  Soil Sci. Soc. Am. J. 38:606-610.  1974.

8.      Fenn, L.B. et al. Ammonia losses from surface-applied nitrogen fertilizer as
       controlled by soluble calcium and magnesium:  general theory.  Soil Sci. Soc. Am. J.
       45:777-781.  1981.

9.      Fenn, L.B. and Miyamoto.  Ammonia loss and associated reactions of urea in
       calcareous soils.  Soil Sci. Soc. Am. J.  45:537-540.  1981.

10.     National Research  Council.  Subcommittee on Ammonia.  University Park Press.
       Baltimore, Maryland. 1978.

11.     Forster, J. and H. Lippold.  Ammoniakverluste bei Harnstoffdungung - 2  Mitteilung:
       Ermittling von Ammoniakverlusten unter Feldbedingungen in Abhangigkeit von
       Witterung. Archiv fur Acker- und Pflanzenbau und Bobenkunde 19:631-639.  1975.
                                         3-11

-------
12.    Cass, G.R.  The origin of ammonia emissions to the atmosphere in an urban area.
       Open File Report 82-6.  Environmental Quality Laboratory.  California Institute of
       Technology.  1982.

13.    Bottger, A.  et al. Atmospharische Kreislaufe von  Stickoxiden und Ammoniak.  Ber.
       Kernforschundsanlage Julich, Nr. 158.  1978.

14.    Slemr, F. and W. Seller. Field measurements of NO andNO2 emissions from fertilized
       and unfertilized soils. J. Atmos. Chem. 2:1-24. 1984.

15.    Sanders, L.  Nitrogen balance experiments under forage maize and grass.  J. Sci. Food
       Agr 31:846-847.  1980.

16.    Whitehead,  D.C. and N. Raistrick. Ammonia volatilization from five nitrogen
       compounds  used as fertilizers following surface application to soils.  J. of Soil  Science
       41:387-394.  1990.

17.    van der Most, P.FJ and C. Veldt.  Emission Factors Manual Parcom-Atmos:
       Emission factors for air pollutants 1992.  Prepared by TNO Environmental and Energy
       Research for the Netherlands Ministry of Housing, Physical Planning, and the
       Environment, Air and Energy Directorate. Reference No. 92-235. September 1992.

18.    Al-Kanani, T., et al.  Soil Water and Ammonia  Volatilization Relationships with
       Surface-Applied Nitrogen Fertilizer Solutions.  Soil Sci.  Soc. Am. J.  55:1761-1766.
       1991.

19.    Ismail, K.M., et al. Modeling ammonia volatilization from loamy  sand soil treated
       with liquid urea. Trans, of the ASAE  34(3):756-763.  1991.

20.    Burch, J. A. and R. H. Fox.  The effect of temperature and initial soil moisture content
       on the volatilization of ammonia from surface-applied urea.  Soil  Sci.  147(5):311-318.
       1989.

21.    Mclnnes, KJ. et al.  Field Measurements of Ammonia Loss from Surface Applications
       of Urea Solution to Bare Soil.  Agronomy J.  78:192-196.  1986.

22.    Rachhpal-Singh and P.H. Nye.  A model of ammonia volatilization from applied urea.
       I, II, and III.  J. of Soil Sci. 37:9-40.  1986.

23.    Kirk, GJ.D and P.H. Nye.  A model of ammonia volatilization from applied urea.  V
       and VI.  J. of Soil Sci. 42:103-125. 1991.

24.    Al-Kanani, T. and A.F.  MacKenzie.  Effect of tillage practices and hay straw on
       ammonia volatilization from nitrogen fertilizer solutions.  Can. J. of Soil Sci.  72:145-
       157.  1992.
                                         3-12

-------
25.     All, Abdul-Mehdi S. and J.L. Stroehlein. Reactions of urea phosphate in calcareous
       and alkaline soils: I. Ammonia volatilization.  Comtnun. in Soil Sci. Plant Anal.
       22(11&12):1243-1256.   1991.

26.     Watson, CJ. et al.  Volatilization of ammonia from solid and liquid urea surface-
       applied to perennial ryegrass.  J. of Agr. Sci. 119:223-226.   1992.

27.     Shahandeh, H. et al.  Ammonia Volatilization from Urea, Ammonium Sulfate, and
       Nutrasweet Sludge in Bare and Straw-Covered Soils. Commun Soil Sci. Plant Anal.
       23(7&8):775-786.  1992.

28.     O'Halloran, IP.  Ammonia Volatilization from Liquid Hog Manure:  Influence of
       Aeration and Trapping Systems.  Soil Sci. Soc. Am. J. 57:1300-1303.  1993.

29.     De Datta, S.K. et al. Direct Measurement of Ammonia and Denitrification Fluxes
      from Urea Applied to Rice.   Soil Sci.  Soc. Am. J.  55:543-548.  1991.

30.     Bouldin, D.R,  et al.  Urea Transformations in Flooded Soil Columns:  II. Derivation
       of Model and Implications to Ammonia Volatilization. Soil  Sci. Soc. Am. J.  55:1135-
       1142.  1991.

31.     Jayaweera, G.R. and D.S. Mikkelsen.  Ammonia Volatilization from Flooded Soil
       Systems: A Computer Model.  I.  Theoretical Aspects.  Soil Sci. Soc. Am.  J.
       54:1447-1455.  1990.

32.     Census of Agriculture - Volume 1, Geographic Area Series (CD-ROM). Department of
       Commerce, Bureau of Census, Washington, D.C.  1987.

33.     North Carolina Fertilizer Tonnage Report 1993.  North  Carolina Agricultural
       Statistics, Raleigh, NC.  December 1993.
                                         3-13

-------
                                     SECTION 4

                       AMMONIA EMISSIONS IN INDUSTRY


4.1 CATEGORIES INCLUDED IN THE 1985 NAPAP INVENTORY

       The 1985 NAPAP inventory included the following six industrial categories for which
NH3 emission factors were developed:

  •     Ammonium Nitrate Production
  •     Ammonia Synthesis
  •     Urea Manufacture
  •     Ammonium Phosphate Manufacture
  •     Petroleum Refineries
       Coke Manufacture

A research and development study report, prepared for NAPAP in  1990, identified and
compared emissions factors developed by NAPAP with emissions factors developed by
others.1 The report recommended emission factors for inclusion in the 1985 NAPAP
Emissions Inventory. In general, the NAPAP NH3 emission factors for industrial sources
were the same factors as those presented in the U.S. EPA emission factor manual AP-42.2

       The U.S. EPA has recently updated the emission factor manual AP-42.  The fifth
edition of AP-42 has revised  sections for ammonium nitrate production, NH3 synthesis, urea
manufacture, and ammonium phosphate manufacture. The revised sections present changes to
the emission factors and the quality rating  associated with the factors from both the earlier
AP-42 sections and the NAPAP  NH3 emission factors. For all six of the industrial categories
listed above, the AP-42 factors are recommended for use in future NH3 inventory
development efforts.  Table 4-1 presents the NH3 emission factors from the latest version of
AP-42.

4.2 ADDITIONAL  SOURCES OF AMMONIA EMISSIONS

       Several industrial sources of NH3 emissions were identified in the current study,  which
had not been included in the  1985 NAPAP inventory or in other previous NH3 emissions
inventories.  The sources and methods used to identify these additional sources included:

       EPA's Toxics Release Inventory System (TRIS) data base
  •     The California "hot spot" air toxics emissions inventory
       Contacts with State agencies
       Literature on industrial users of ammonia
                                         4-1

-------
TABLE 4-1.  SUMMARY OF INDUSTRIAL AMMONIA EMISSION FACTORS
Source
Ammonium Nitrate Manufacture6
Neutralizer


Evaporation/concentration

Solids Formation Operations
high density prill towers
low density prill towers
rotary drum granulators
pan granulators
Coolers and dryers8
high density prill coolers
low density prill coolers
low density prill dryers
Petroleum Refineries
FCC units

TCC units (moving bed catalytic
cracking units)
Reciprocating engine compressors

Point
Source
scca

3-01-027-04
3-01-027-11
3-01-027-21
3-01-027-17
3-01-027-27

3-01-027-12
3-01-027-22
3-01-027-07
3-01-027-08

3-01-027-14
3-02-027-23
3-01-027-25

3-06-002-01

3-06-003-01

h

Emission
Factor
(kg/unit)

0.43-18.0


0.27-16.7


28.6
0.13
29.7
0.07

0.02
0.15
0-1.59

0.155

0.017

3.2

Units

Mg of product


Mg of product


Mg of product
Mg of product
Mg of product
Mg of product

Mg of product
Mg of product
Mg of product

103 liters fresh
feed
103 liters fresh
feed
103 m3 gas
burned
Emission
Factor
Ratingb

B


A


A
A
A
A

A
A
A

B

B

B

Emission
Factor
(Ib emitted/
SCC unit)c

0.86-36.0


0.54-33.4


57.2
0.26
59.4
0.14

0.04
0.30
0-3.18

54

6

0.2

1985
Emissions
(kg/yr)d

8,082
9,898
3,665
2,225
1,237

30,955
38
1,819
f

7.3
0
52.6

19,411

24

h

                         (Continued)

-------
                                             TABLE 4-1 (Continued)
Source
NH3 Synthesis
Carbon dioxide regeneration
Condensate steam stripping
Urea Manufacture
Solution formation/concentration
Solids formation
nonfluidized bed prilling
agricultural grade*
fluidized bed prilling1"
agricultural grade
feed grade
drum granulation
rotary drum cooler
Coke Manufacture"
Wet coal oven charging - Larry car
Door leaks
Coke pushing
Ammonium Phosphate Manufacture
Point
Source
scca
3-01-003-08
3-01-003-09

3-01-040-02

3-01-040-08
3-01-040-10
3-01-040-11
3-01-040-04
3-01-040-12

3-03-003-02
3-03-003-08
3-03-003-03
3-01-030°
Emission
Factor
(kg/unit)
1.0
1.1

9.231

0.43
1.46
2.071
1.07m
0.0256

0.01
0.03
0.05
0.07
Units
Mg of product
Mg of product

Mg of product

Mg of product
Mg of product
Mg of product
Mg of product
Mg of product

Mg coal charged
Mg coal charged
Mg coal charged
Mg P205
produced
Emission
Factor
Ratingb
E
E

A

A
A
A
A
A

D
D
D
E
Emission
Factor
(Ib emitted/
SCC unit)c
2.0
2.2

18.461

0.87
2.91
4.141
2.15m
0.051

0.02
0.06
0.1
0.14
1985
Emissions
(kg/yr)d
2,221
1,571

20,014

0
340
9.5
1,314
.045

162
293
618.7
259
"Refers to SCCs that were in the 1985 NAPAP Emission Inventory.




bSee Appendix A of this report for a definition of the ratings.




°A11 factors chosen are from AP-42.
                                                    (Continued)

-------
                                                  TABLE 4-1 (Continued)

dEmissions are from the 1985 NAPAP emission inventory and totals do not include 20,057 Mg from minor point source process emissions; area
source category 99.

eGiven as ranges because of variation in data and plant operations.  All factors are uncontrolled, factors for controlled emissions are not presented
due to conflicting results on control efficiency.

fNH3 emissions from pan granulators were not presented by Warn et al. (1990) and were not included in the  1985 NAPAP emission inventory.

gFactors for coolers represent  combined precooler and cooler emissions, and factors for dryers  represent combined predryer and dryer emissions.

hNot available.

'EPA test data indicated a range of 4.01 to  14.45 kg/Mg (8.02 to 28.90 Ib/ton).

Teed grade factors were determined at an ambient temperature of 14° to 21° C (57° to 69°F).

kFeed grade factors were determined at an ambient temperature of 29°C (85°F) and agricultural grade factors at an ambient temperature of 27°C
(SOT).

'For fluidized bed prilling, feed grade, there is a controlled emission factor with an A rating of 1.04 kg/Mg (2.08 Ib/ton of product) based on use of
an entrainment scrubber.

mEPA test data indicated a range of 0.955 to 1.20 kg/Mg (1.90 to 2.45 Ib/ton).

"All factors are for uncontrolled emissions.

°The emission factor is for the whole plant,  all processes.
                                                         (Continued)

-------
The following additional industrial sources of NH3 were identified:

  •     Beet Sugar Production
  •     Froth Flotation
  •     Mineral Wool Production
       Pulp and Paper
       Metals Processing
       Other Miscellaneous Sources

Each of these  industries was investigated to determine the potential for the development of an
NH3 emission factor.  Wherever possible, emission factors were developed.  The following
sections present recommendations for emission factors and for the treatment of emission
sources for which emission factors could not be developed.

4.2.1  Beet Sugar Production

       A review of the  1992 TRIS database revealed that there are 11 major (>90.72 Mg per
year NH3 emissions) beet sugar processing plants, which have combined NH3 air emissions of
2,323 Mg per year.  Of these  11  plants, The Amalgamated Sugar Company  (Amalgamated)
operates 4 plants, accounting for 55 percent of the total NH3 emissions reported by the 11
major plants.  The Corporate Environmental Engineer for Amalgamated, as well as the Kirk-
Othmer Encyclopedia of Technological Processes, were consulted to determine the sources of
NH3 in the industry.3'4

       Ammonia is a by-product of beet-sugar production.  All North American beet-sugar
factories use lime and carbon dioxide juice purification.  The effectiveness of this process is
based on the direct action of the lime on impurities, and on the special adsorptive properties
of the calcium carbonate precipitate formed after carbonation. Treatment with lime produces
precipitates and soluble  solids.  The reactions leading to soluble solids are mostly caused by
the hydroxyl ions produced by the lime.  Of the soluble products of this process:

  •     ammonium salts  give off NH3;

  •     asparagine and glutamine are  converted to their respective amides, which are
       hydrolyzed with  the evolution of NH3, and accumulate as calcium salts in the juices;

  •     allantoin decomposes slowly to NH3, carbon dioxide, calcium  glycolate, and a
       precipitate of calcium oxalate; and

       oxamic acid decomposes, also rather slowly, yielding free NH3 and calcium oxalate.

       Amalgamated provided the estimation method that they used for determining total NH3
emissions for use in the TRIS.  Amalgamated calculates NH3 releases from air stacks and

                                          4-5

-------
vents, from wastewater which is treated by land application, and from wastewater in surface
impoundments.  To determine total NH3, they estimate the sum of the quantity of NH3
contributed from the sugar beets and the quantity of NH3 contributed from the addition of
ammonium bisulfite, which is used as a biocide to control bacteria growth.

       After calculating the total NH3 contributions, a material balance is used to determine
the fate of NH3 in the process.  Their total NH3 release is equal to the sum of the quantity of
NH3 in wastewater applied to land, the quantity of NH3 in storage ponds, and the quantity of
NH3 released from stacks and vents.  The NH3 present in the wastewater applied to land and
the wastewater in surface impoundments is determined by analyzing water samples.
balance is assumed to be emitted to the air.5
                               The
       Since all North American beet sugar production plants utilize the same technology, it
is believed that the method which Amalgamated uses to calculate NH3 emissions is an
acceptable method to apply industry-wide. As previously stated, total annual NH3 is derived
by calculating NH3 contributed from beets to NH3 contributed from ammonium bisulfite.
Ammonia from beets, in kilograms, is estimated by multiplying the annual amount of beets
sliced by 0.9916 x 10"4. NH3 from ammonium bisulfite, in kilograms, is estimated by
multiplying the number of liters of ammonium bisulfite used annually by 0.1603.
Amalgamated estimates that NH3 from ammonium bisulfite contributes about 20 percent of
the total NH3 emissions.  It is assumed that total annual NH3 is emitted,  unless sampling
results of other treatment or control (e.g., influent streams to wastewater treatment, water
contained in impoundments) processes indicate that the NH3 is recovered or destroyed.  The
NH3 emission factor for the beet sugar production industry is listed in Table 4-2. The
emission factor quality is rated B, in that the factor is based on a sound  engineering estimate.

 TABLE 4-2.  AMMONIA EMISSION FACTORS FOR BEET SUGAR PRODUCTION


Source

Point Source
sec
Emission
Factor
(kg NH3/Mg)

Factor
rating
Emission
Factor
(Ib NH3/ton)
Estimated
national emissions
(Mg/yr)
    Sugar Beets   3-02-016-01     0.00262
B
0.00524
2,323
4.2.2  Froth Flotation in Mineral Processing

       Froth flotation is used at minerals processing plants as a minerals separation technique.
While the basic concept of selectively floating minerals applies to all ores, floatation
procedures vary tremendously. In  1991, the U.S. Department of the Interior, Bureau of Mines
performed a flotation survey of all  U.S. mineral processing and coal cleaning plants that were
                                          4-6

-------
believed to use froth flotation.6  The plants were surveyed for, among other things, their
consumption of the reagents typically used in flotation, including NH3. Data were received
from 133 of the 260  active flotation plants.  Of the plants not responding to the survey, 100
were coal preparation plants and the majority of the remaining 27 were industrial  mineral
producers.  The operating  status of the non-responding plants was not determined.

       The results of the survey indicate that 7,691 Mg of NH3 or ammonium hydroxide were
consumed in 1991.  Of this, 71 Mg were used in the froth flotation of 2,300,659 Mg of glass
sand ore; 7,593 Mg were used in the froth flotation of 96,833,621 Mg of phosphate ore; and
27 Mg were used in the froth flotation of 17,115,235 Mg of bituminous coal.  Ammonia is
used as a reagent for pH adjustment, to lower acidity.  Emission factors were estimated by
mass balance,  assuming that all  of the NH3 used is ultimately evaporated to the air.  These
emissions factors are presented in Table 4-3. Although these factors are viewed as reasonable
estimates, it should be noted that the mass balance calculation involves the conservative
assumption that the NH3 does not leave the flotation process as a salt, in solid waste or
wastewater.  The factors are assigned quality ratings of D, because they are based on material
balance with incomplete data.

TABLE 4-3.  AMMONIA EMISSION FACTORS FOR MINERAL ORE PROCESSING
                              BY FROTH FLOTATION

Point Source
Source SCC
Emission
Factor
(kg/Mg)

Factor
rating
Emission
Factor
(Ib/ton)
1991
Emissions
(Mg/yr)
      Glass Sand
3-05-014-20
1000a
D
2000
70
Phosphate
Bituminous Coal
3-05-019-10
3-05-010-18
1000b
1000C
D
D
2000
2000
7,690
27
  "About 70 Mg of NH3 is used per year, or an average of 0.0307 kg/Mg of glass
  produced.
  bAbout 7,690 Mg of NH3 is used per year, or an average of 0.784 kg/Mg of phosphate
  ore.
  cAbout 27 Mg of NH3 is used per year, or an average of 0.00159 kg/Mg of coal
  processed.
4.2.3  Mineral Wool (Fiberglass) Production
                                          4-7

-------
       A thorough review of the U.S. Environmental Protection Agency's 1992 Toxic Release
Inventory  System (TRIS) database reveals that of the 23 fiberglass manufacturing plants that
reported NH3 emissions, 10 are major (>90.72 Mg/year) sources. Of these 10 plants, Owens-
Corning Fiberglass, Incorporated operates 6 and Schuller International, Incorporated  operates
one, accounting for 80% of the total NH3 emissions reported by the  10 major plants.7

       All fiberglass manufacture in the U.S. is  conducted using the same process; therefore,
information obtained from Owens-Corning Fiberglass and Schuller International can  be
applied to all fiberglass manufacturing plants.  Briefly, in  the manufacture of fiberglass, a
phenol formaldehyde resin is used as a component of the binder. The binder is then sprayed
on the fiberglass to allow it to be bound  into usable form  as insulation.  Aqueous NH3, a
component in the resin, is used for adjustment of pH.  During the manufacturing process,
virtually all the NH3 is released and, typically, emitted to the atmosphere. Other sources of
emissions of NH3 at a fiberglass plant include emissions from storage tank facilities, although
these emissions are very minor when compared to emissions from the production process.  In
addition, urea is also used in the process as a prill, and is a  source of some NH3 emissions.
However,  the NH3 emitted from this source is very minor in comparison to emissions from
the production process.8'940

       The fiberglass production facilities approximate their NH3 emissions from records of
the amount of NH3 utilized in the production process.  In  addition, they add a small  amount
(one facility stated that they included approximately 1/2 megagram, or approximately 0.1% of
their total  emissions) to their NH3  use numbers,  to account for NH3 emissions from urea use
in the production process.  The NH3 used in the manufacture of fiberglass can be related to
fiberglass  production numbers, thus it would be  possible to estimate  an NH3 emission factor
based on fiberglass production.

       However, the fiberglass  production industry is currently aggressively researching ways
to reformulate the resins used in the production process to reduce or eliminate the use of
certain organic  compounds.  As resin reformulation occurs, pH adjustment is likely not to be
required, due to the constituents of the resins, and, as a result, NH3 use will be drastically
reduced. Therefore, the use of an  NH3 emission factor, based on the current NH3 use during
fiberglass  production, will likely be inaccurate in the near future, and would require  revision
as advances are made in the research.  As a result, NH3 use  during fiberglass production will
likely provide the best method of estimating NH3 emissions  from these facilities.  In general,
the NH3 usage figures appear to have been reported as  emissions in TRIS.

4.2.4 Pulp and Paper

       Chemical pulping of wood  involves mixing the  raw materials (pulp wood) with
cooking chemicals under controlled temperature and pressure conditions to yield a variety of
pulps with unique properties. Three types of chemical pulping are currently used in the U.S.;
kraft, sulfite, and soda pulping. Of the three types, only  sulfite pulping uses NH3 as an added
reagent. The sulfite process uses an acid solution of sulfurous acid and bisulfite ion. The

                                           4-8

-------
bisulfite may be an ionic salt of calcium, magnesium, sodium, or ammonium.  At sulfite mills
that use ammonium salts, energy and sulfur are recovered; however, pulping liquor cannot be
recovered, because ammonium combustion generates elemental nitrogen and water.  The
composition of the cooking liquor is 7 percent sulfur dioxide, by weight, of which 4.5 percent
is present as sulfurous acid and 2.5 percent as calcium,  sodium, NH3,  or magnesium
bisulfite.11  There are currently eight ammonium-based pulping mills in the U.S.

       The National Council  of the Paper Industry for Air and Stream Improvement, Inc.
(NCASI) published a Handbook of Chemical Specific Information for  SARA Section 313 Form
R Reporting in March 1990.12 This publication contains information on NH3 use and
emissions in the pulp and paper industry, which is summarized and presented in the following
text.

       Ammonia is produced or used in various processes throughout the pulp and paper
industry. It is coincidentally  manufactured in the Kraft  pulping process in the recausticizing
area and the anaerobic treatment systems.  No data on NH3 production were available to
NCASI, however they estimated that only trace amounts may be present in these processes.
NH3 may also be present in dyes, coatings,  and inks which would be used to produce a final
product.  NCASI indicated that recent measurements at  one mill showed that 50 percent of
the NH3 applied to the paper  machine  with coating chemicals was released to the  atmosphere.
Ammonia may also be used as an additive to the wastewater, for nutrient purposes, prior to
secondary wastewater treatment. Typically, this NH3  is added as aqueous NH3, of which only
a fraction is in the free form, and 90 to 95 percent is  expected to be consumed during the
treatment process. NCASI studies have found that NH3 is present in very small quantities
(0.5 ppm as total NH3) in treated mill  effluents.  And, finally,  NH3 is  used as a raw material
in pulping liquor used in the sulfite pulping process.  This pulping liquor is typically not
recovered, however NH3 emissions may be incidentally  controlled via the control  methods
used for sulfur dioxide to reduce odor emissions.

       The information  on estimating NH3 air emissions from  fugitive or non-point sources
indicates that most of the NH3 would be released as fugitive emissions from a secondary,
biological waste treatment facility, and would amount to less than 226.8 kg (or 500 Ibs) per
year.  Additional potential emission sources include accidental or fugitive  emissions from tank
car loading, and emissions from vents on storage tanks; however, no estimates of emissions
were available to NCASI.

       The information  on estimating NH3 air emissions from  stack or point sources  indicates
that there are four potential sources:  dryer/printing press vents, paper machine vents,
recausticizing area vents, and anaerobic treatment system vents.   As previously stated,
NCASI indicated that recent measurements at a mill showed that 50 percent of the NH3
applied to the  paper machine  with coating chemicals was released to the atmosphere. No data
were available to NCASI on the other three potential  point sources.
                                          4-9

-------
       The data collected and analyzed on NH3 air emissions from the pulp and paper
industry were not sufficient to develop an NH3 emission factor for the industry.  However, the
guidance provided to the industry by the trade group NCASI seems to be comprehensive and
would  allow plants to adequately calculate NH3 emissions, based on their specific plant
operating factors.  As a result, NH3 emissions, as reported in TRIS, will likely provide the
most accurate report of NH3 emissions from pulp and paper facilities and is recommended for
use.  It is also recommended that further research be conducted in the pulp and paper industry
to determine if development of an NH3 emission factor is feasible and can be accomplished.

4.2.5  Emission Factors Provided by Other Sources

       California  maintains an Air Toxics Emission Data System (ATEDS) under its Air
Toxics Hot Spots  program.  This data system contains plant- and point-specific information
for specific toxic pollutants, including NH3, at the same level of detail as the EPA AIRS point
source  inventory for criteria pollutants.  The data include plant name, equipment type,  SCC,
SIC, emission  factor (for each specific pollutant), and emissions.  The emission factors in
ATEDS are plant-specific, and generally vary from plant to plant within the same SCC.

       Ammonia  emissions data  and emission factors were obtained from ATEDS,  and
reviewed to assess their applicability to a national inventory.  Most of the NH3 emissions
reported in ATEDS derive from the use of NH3 in selective  catalytic reduction and  selective
non-catalytic reduction processes for controlling nitrogen oxide  emissions from combustion
sources. NH3  emissions from these processes are discussed in Section 5. Another large
fraction of the NH3 emissions in  ATEDS is reported in the form of plant totals, with no
source  specific information on emissions or emission factors. A relatively small portion of
the inventory deals with source-specific industrial NH3 emissions data.

       Table 4-4 gives emission  factors for industrial sources of NH3 emissions, which were
developed from the California ATEDS data base.13 For each source type, the table  presents
the average ATEDS NH3 emission factor, the range of NH3 emission factors, the  emission
factor units, the applicable AIRS SCC, the number of plants included in ATEDS, and the
recommended  emission factor rating.  A rating of D is used in all cases because of the limited
number of sources in each category, and because  emission factors for the California sources
may not be representative of the  nation as a whole. EPA does not recommend using fixed
emission factors for emissions from storage tanks, but instead recommends a case by case use
of the EPA "TANKS" program,  which will work  for ammonia,  with use of the proper
constants.

4.2.6  Other Sources (For Which Emission Factors Have Not Been Developed)

       The TRIS  data base stems from the toxic release report requirement in Section  313 of
SARA Title III. In summary, annual toxic release reports must be submitted for  any
manufacturing plant (SICs 20-39) that produces or processes more than 11,340 kg (25,000 Ib)
per year of a listed chemical, or that otherwise uses more than 4,536 kg (10,000 Ib) per

                                         4-10

-------
      TABLE 4-4.  AMMONIA EMISSION FACTORS DEVELOPED FROM THE
                           CALIFORNIA ATEDS DATA BASE
Category Description
Ammonia storage

Gold processing,
electrowinning
Coal mining, unloading
(cyanide ponds)
Crude oil production
Complete well, fugitives
Crude oil sumps
Storage - breathing

Storage - working

Crude oil loading

Emission factors
(kg/unit)
Average Range
6.6x1 0'8

0.029 7xlO-7to0.17

0.017


5.9xlO'7 2.3xlO-7to l.lxlO'6
2.1xlO'5 3xlO'7 to 4.3xlO'5
2.6xlO'6 7x10-" to 7xlO'6

1.7xlO-8 5xlO-10 to 7xlO-7

3xlO'9 7xlO-10 to 6xlO-7

Units

103 liters
capacity
Mg

Mg


Wells
Meters2
103 liters
capacity
103 liters
thruput
103 liters
thruput
sec
30188501

30301301

30504099


31000101
31000104
40400301

40400302

40600132

No. of
plants
1

6

1


3
2
2

4

1

Rating3
D

D

D


D
D
D

D

D

  a A rating of D is used in all cases because of the limited number of sources in each category, and because emission
  factors for the California sources may not be representative of the nation as a whole. EPA does not recommend using
  fixed emission factors for emissions from storage tanks, but instead recommends a case by case use of the EPA
  "TANKS" program, which will work for ammonia, with use of the proper constants.
year.    NH3 is one of the listed chemicals for TRIS.  SARA reports provide estimates of
fugitive and stack emissions; releases to surface water or land (including deep well injection);
transfers to publicly-owned wastewater treatment works (POTWs); and transfers to off-site
waste treatment,  storage and disposal facilities (TSDFs).  Information is also provided on
emission controls, on-site treatment, and pollution prevention measures.  Unfortunately,  no
direct link is made in the  data base between pollution controls and specific emission streams.
Thus, no information is available on the fraction of total plant emissions routed to a given
control  device or, consequently, on the exact magnitude of emissions collected.  In addition,
TRIS provides no details on individual sources of emissions for any pollutant, beyond the
gross plant level.

       Table 4-5 gives a summary by industry category of NH3 emissions reported in TRIS
for 1992 and 1990, along with an indication of which categories are covered by emission
factors.  With the available emission factors for fertilizer manufacture, refrigeration, coke
                                            4-11

-------
production, petroleum refining, and other categories, about 75 percent of the 1992 emissions
in Table 4-5 are covered by emission factors.

       In cases where there are no applicable  emission factors, it is recommended that plants
reporting NH3 emissions in TRIS be incorporated into the emission inventory as "discrete
point sources." TRIS gives information on latitude and longitude, as well as State and county
codes, which can be used to give the location  of these discrete sources. Tabe 4-6 gives a list
of discrete sources, with no applicable emission factors, that are reported to emit more than
90.72 Mg of NH3 annually in the 1992 TRIS data base.

       NH3 emissions from the discrete source groups were assessed with the goal of
developing emission factors.  One problem is that there are only a few cases where there is a
well defined "category" with more than a few sources. For instance, the nonferrous  metals
group (SIC 3339) includes four major sources, but these  produce a variety of different metals.
Similarly, SICs 2819 and 2869 are both broad categories that include a variety of inorganic
chemicals and organic chemicals, respectively.
                                          4-12

-------
  TABLE 4-5.  SUMMARY OF AMMONIA EMISSIONS REPORTED IN TRIS
SIC and Category Description
20
21
22
23
24
25
26
27
281
282
283
284
285
286
287
289
29
30
31
32
33
34
35
36

37
38

39
Food products
Tobacco products
Textiles
Apparel
Lumber and wood products
Furniture and fixtures
Paper
Printing and publishing
Industrial inorganic chemicals
Plastics and resins
Pharmaceuticals
Soap and detergents
Paints and varnishes
Industrial organic chemicals
Agricultural chemicals
Miscellaneous chemicals
Petroleum refining
Rubber and plastic products
Leather
Stone, clay, glass, and concrete
Metal smelting and refining
Fabricated metal products
Industrial machinery
Electronic and electrical
equipment
Transportation equipment
Measurement and control
instruments
Miscellaneous manufacturing
Reported
emissions
in 1992
(Mg)
7,818
613
670
100
411
8
1,948
55
4,466
901
356
463
12
2,895
37,584
511
3,566
1,021
259
2,656
5,476
263
147
579

261
35

106
Reported
emissions
in 1990
(Mg)
7,158
655
779
88
290
9
1,650
50
4,941
860
293
829
9
2,932
56,554
582
3,978
1,072
186
1,108
7,759
349
446
431

237
90

18
Emission
factor
avail- Emission factor description
able?a
Yes Sugar and refrigeration







Yes Ammonia and some
overlap with fertilizers





Yes Nitrogen fertilizers and
phosphate ore processing

Yes Petroleum refining



Yes Coke manufacture








"Emission factors are presented in earlier tables in this section.
                                       4-13

-------
          TABLE 4-6.  LIST OF DISCRETE MAJOR SOURCES (>90.72 Mg or >100 tons) OF
                      AMMONIA WITH NO APPLICABLE EMISSION FACTORS
                                         (based on 1992 TRI reports)
Category1
Electrometallurgy
Misc. Nonferrous
Metals
Plastic Parts
Fertilizer Mixing
Misc. Inorganic
Chemicals
Tobacco Products
Mineral Wool
and Fiberglass
Secondary Nonferrous
Smelting
Steel Wiredrawing
Forging
Pulp and Paper
Miscellaneous
Organic
Chemicals
Cyclic Organics
and Dyes
Synthetic Rubber
Wood Preserving
Miscellaneous
Plant
Elkem Metals Co.
Climax Molybdenum Co.
U.S. Vanadium Corp.
GTE Prods. Corp.
Cabot Corp.
GECo.
Teepak Inc.
O. M. Scott & Sons Co.
W. R. Grace & Co.
Du Pont Repauno Plant
Calgon Carbon Corp.
Engelhard Corp.
Westinghouse
Filtrol Corp.
Peninsula Copper Ind. Inc.
Griffin Corp.
Kerr-Mcgee Chemical Corp.
W. R. Grace & Co.
PPG Ind. Inc.
United Catalysts Inc.
Philip Morris USA
Owens-Coming Fiberglas
Owens-Corning Fiberglas Corp.
Owens Corning Fiberglas Corp.
Schuller Intl. Inc.
Owens-Coming
Manville Sales Corp.
Certainteed Corp.
Owens-Corning Fiberglas Corp.
Owens-Corning Fiberglas Corp.
Partek Insulation Inc.
Gulf Chemical & Metallurgical
Alabama Reclamation Plant
Indiana Steel & Wire Corp.
National Forge Co.
Bowater Inc.
Mead Coated Board Inc.
Champion Intl. Corp.
Sherex Chemical Co. Inc.
PCR Inc.
Ethyl Petroleum Additives Inc.
DuPont
Rohm & Haas Texas Inc.
Exxon Chemical Americas
Ethyl Corp.
BASF Corp.
DuPont
Sandoz Chemicals Corp.
Buffalo Color Corp.
Ameripol Synpol Corp.
J. H. Baxter & Co.
M-Pact
City
Marietta
Fort Madison
Hot Springs
Towanda
Boyertown
Euclid
Swansea
Marysville
Sulphur
Gibbstown
Pittsburgh
Attapulgus
Columbia
Los Angeles
Hubbell
Casa Grande
Hamilton
Baltimore
New Martinsville
Louisville
Richmond
Newark
Kansas City
Waxahachie
Defiance
Fairburn
Winder
Mountain Top
Santa Clara
Delmar
Phenix City
Freeport
Sheffield
Muncie
Irvine
Catawba
Cottonton
Hamilton
Mapleton
Gainesville
Natchez
Orange
Deer Park
Baytown
Orangeburg
Freeport
Victoria
Charlotte
Buffalo
Port Neches
Weed
Eudora
State
OH
IA
AR
PA
PA
OH
SC
OH
LA
NJ
PA
GA
SC
CA
MI
AZ
MS
MD
WV
KY
VA
OH
KS
TX
OH
GA
GA
PA
CA
NY
AL
TX
AL
IN
PA
SC
AL
OH
IL
FL
MS
TX
TX
TX
SC
TX
TX
NC
NY
TX
CA
KS
SICs
i st ^nd ord
3313
3339 2819
3339 1094
3339 3341 2819
3339 2819
3399 3356 3357
3089
2875
2819
2819
2819
2819
2819
2819
2819
2819
2819 3313
2819
2812 2819 2865
2819
2141
3296
3296
3296
3296
3296
3296
3269
3296
3296
3296
3341
3341
3315
3462
2611 2621
2631
2621
2843 2899 2869
2869
2869
2869
2869
2869 2821
2869 2834
2869
2869
2865
2865
2822
2491
3998
Reported
emissions
(Mg/yr)
L542
814
261
154
152
305
753
680
640
474
273
210
166
163
160
122
108
98
97
91
530
436
276
180
161
145
143
127
119
113
93
318
281
313
132
282
245
114
318
204
181
165
165
149
118
110
104
126
104
118
117
100
"Plants are grouped by SIC code and sorted in descending order of ammonia emissions. The following SICs are excluded because of overlap with emission
factor categories: 20xx - food processing (ammonia refrigeration, see Section 6), 2873 - Nitrogen fertilizers, 2874 - phosphates, 29xx - petroleum refining,
and 3312 - steel works (coke ovens).


                                                      4-14

-------
                          REFERENCES FOR SECTION 4

1.     Warn, T.E., S. Zelmanowitz, and M. Saeger.  Development and Selection of Ammonia
      Emission Factors for the 1985 NAPAP Emissions Inventory.  EPA-600/7-90-014. U.S.
      Environmental Protection Agency, Research Triangle Park, North Carolina. June
      1990.

2.     U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission
      Factors -  Volume I: Stationary Point and Area Sources.  AP-42  (GPO 055-000-00251-
      7). Fifth Edition.  U.S. Environmental Protection Agency,  Research Triangle Park,
      North Carolina.  July 1994.

3.     Kirk-Othmer, Encyclopedia of Chemical Technology, Vol.  21, pp. 904-921.  1978.

4.     Personal conversation.  Calvin Overcash, EC/R Inc.  with Dean DeLorey,  Corporate
      Environmental Engineer, The Amalgamated Sugar Company, Nampa, Idaho. June
      1994.

5.     Letter from Dean DeLorey, Corporate Environmental Engineer,  The Amalgamated
      Sugar Company, Nampa, Idaho.  Dated June 16,  1994.

6.     U.S. Department of the Interior, Bureau of Mines, Mineral  Industry Surveys,
      Washington, DC. Froth Flotation in the United States,  1991.  Prepared in the Branch
      of Metals  and Branch of Data Collection and Coordination, September 20, 1993.

7.     U.S. Environmental Protection Agency, Toxic Release Inventory System database.

8.     Personal conversation.  Calvin Overcash, EC/R Inc.  with Robin Bennett, Plant
      Environmental Engineer, Owens-Corning Fiberglass, Newark,  Ohio. June 1994.

9.     Personal conversation.  Calvin Overcash, EC/R Inc.  with Dan Vanmetre,  Corporate
      Engineer responsible for air issues, Owens-Corning Fiberglass, Toledo, Ohio.  June
      1994.

10.    Personal Conversation.  Calvin Overcash, EC/R Inc. with Dave Carleski,  Schuller
      International, Incorporated, Defiance, Ohio.  June 1994.

11.    U.S. Environmental Protection Agency, Office of Water. Development Document of
      Proposed Effluent Limitations Guidelines and Standards for the Pulp, Paper, and
      Paperboard Point Source Category, EPA-821-R-93-019, October 1993.

12.    The National Council of the Paper Industry for Air and Stream Improvement, Inc.
      (NCASI),  Handbook of Chemical Specific Information for SARA Section 313 Form R
      Reporting, pp. 3.A.250-3.A.253, March 1990.
                                        4-15

-------
13.    Letter and two data diskettes to R. Battye, EC/R Incorporated, Durham, NC from
      Richard Bode, California Air Resources Board,  Sacramento, CA.  May 16, 1994.

14.    Toxic Chemical Release Inventory Reporting Package for 1989.  EPA-560/4-90-001,
      U.S. Environmental Protection Agency, Office of Toxic Substances, Washington, D.C.
      1990.
                                        4-16

-------
                                      SECTION 5

                   AMMONIA EMISSIONS FROM COMBUSTION
       Ammonia is emitted from several types of combustion processes, including boilers,
cars, and open burning.  In the United States,  emissions from electric and industrial
combustion may be the largest source of NH3  emissions from combustion; however, in recent
global  climate studies, NH3 from biomass burning is estimated to be a significant source of
NH3.  There is a great deal of uncertainty associated with all of the NH3 emission factors
from combustion.  In addition to the release of NH3 as a byproduct of incomplete combustion,
NH3 is used as an agent in NOX control technology; specifically, it is used in selective
catalytic reduction  (SCR) and selective non-catalytic reduction (SNCR).  Ammonia is also
believed to be emitted from the chemical agents used to fight forest fires, although this source
has not been found in the literature.1  This section presents a discussion of the NH3
combustion emission factors used in different  inventory efforts and a discussion of the
plausible emissions of NH3 from NOX control  technology.

       Asman (1992)2 created an emission inventory for all of Europe, but he stated that
although car exhaust, sewage sludge, combustion/coking of coal, and landfill are sources of
NH3, they are very uncertain and not very important sources.

5.1 AMMONIA EMISSION FACTORS FOR COAL COMBUSTION

       Among recent NH3 inventory efforts, there is large variability in the emission factors
used to estimate NH3 emissions from coal combustion.  A review of recent literature
uncovered one test program, conducted by Bauer and Andren (1985)3 in 1980, where NH3
emissions from a coal-fired power plant in Portage, Wisconsin were measured.  The results of
this study were used by Warn (1990)4 to develop the NAPAP coal combustion emission
factor of 0.28 kg NH3/103  Mg coal  (0.56 Ibs NH3/103 tons coal).5 Use of this factor in the
1985 NAPAP inventory resulted in 0.02% of the NH3 inventory. The data of Bauer and
Andren (1985) appear to be the most recent measurements  of NH3  from coal combustion.

       Lee and Longhurst (1993)6 developed an NH3 emission factor for the United  Kingdom
for the 1987 study  year.  They cite several emission factors for coal combustion, including 1
kg NH3/Mg coal combusted, as reported by the Subcommittee on Ammonia (1979).7  This
value was also used by Buijsman (1986).8   Moller & Schieferdecker (1989)9 use the factor
of 6-9  g NH3(N)/Mg of coal in their development of an NH3 emission inventory for  the
G.D.R.  They cite as their source Bottger et al. (1978), and note that the value used  by
Buijsman (1986) of 1 kg NH3/Mg is improbably high.  Kruse et al.  (1989),10 in his work on
the validity and uncertainty of NH3 emissions  from  agriculture,  also notes that the value of 1
kg NH3/Mg coal combusted appears to be too high, because most coal is used in highly
oxidizing combustion processes, leaving little  scope for the formation of NH3.
                                          5-1

-------
       Lee (1994)   has recently submitted a manuscript on the uncertainties of NH
                                                                           3
emission factors.  He cites the work of Warn (1990) for NAPAP as an emission factor of 0.21
g NH3-N for coal combustion based on measurements from one plant.  Geadah (1985)12
gives a residential coal burning emission factor of 1 kg NH3/Mg of coal combusted.  He does
not explain how this emission factor was derived, but he justifies the magnitude of the
estimate on the basis that most domestic coal burning occurs in less than ideal combustion
conditions.

      Denmead (1990)13 developed an NH3 budget for Australia and included an estimate
from coal burning using  an emission factor by Robinson  and Robins (1972)14  of 1 kg NH3-
N/Mg coal.

      Table 5-1 summarizes the various emission factors presented in the literature  for coal
combustion. Although the NAPAP factor  of 0.28 kg NH3/103 Mg (0.56 Ib NH3/103 tons)
burned is based on only  1 test, it remains the most  tenable factor and is recommended  for
continued use as the NH3 emission factor for coal combustion.  The rating for the coal
combustion emission factor is E, consistent with the rating provided by Warn  et al. (1990).

        TABLE 5-1. COAL COMBUSTION AMMONIA EMISSION FACTORS
                Source                   Emission Factor          Emission Factor
                                          (kg/Mg coal)             (Ib/ton coal)

   NAPAP                          0.00028                   0.000565

   Subcommittee on Ammonia        1.0                       2.0
   (1979)

   Buijsman (1986)                  1.0                       2.0

   Lee and Longhurst (1993)         .009                      0.0018

   Moller & Schieferdecker (1989)    0.006-0.009               0.0012-0.0018

   Bottger et al. (1978)              0.006-0.009               0.0012-0.0018

   Denmead (1990)                  1                         2.0
                                         5-2

-------
5.2 AMMONIA EMISSIONS FROM FUEL OIL AND NATURAL GAS
       COMBUSTION

       Only the NAPAP NH3 emission factor documentation includes factors for fuel oil and
natural gas combustion.  The NAPAP factor for fuel oil is the average of two factors, 0.023
and 0.18 kg NH3/103 liters (0.19 and 1.5  Ibs NH3/103 gallons) that were reported by EPRI in a
1976 document.15 The factor lies within  the range 0.0072 to 0.96 kg NH3/103 liters (0.06 to
8 Ibs NH3/103 gallons) that was established in two studies conducted in the 1950's.16
Ammonia emissions from natural gas combustion were estimated in the 1950's  and 1960's to
range from 5 to 300 kg NH3/106 m3 (0.3  to 20 Ibs NH3/106 ft3).  The 1976 EPRI study also
measured NH3 from natural gas combustion at excess oxygen levels of 2, 4, and 6 percent.
These data were  combined with excess oxygen  statistics that were presented by Cass
(1982)17 to calculate average emission factors for  utility, industrial, and commercial boilers.
The emission factors used  for fuel oil and natural gas combustion in the NAPAP inventory
are presented in Table 5-2.

    TABLE 5-2. NAPAP FUEL OIL AND NATURAL GAS EMISSION FACTORS
Source
Fuel Oil


Natural gas - utility and
industrial boilers
Emission Factor
0.096 kg/103 liter
51. kg/106m3
Factor
Rating
E
C
Emission Factor
0.8 lb/103 gal
3.2 lb/106 ft3
   Natural gas - commercial     7.8 kg/106 m3           C           0.49 lb/106 ft3
   boilers
       Although emission factors were developed for fuel oil and natural gas combustion,
NH3 emission estimates for these categories were not included in the  1980 NAPAP emission
inventory.  Using these factors in the 1985 NAPAP inventory resulted in NH3 emissions of
1.2% for fuel oil and 2.2% for natural gas combustion. (Both of these emission estimates are
substantially higher than for coal combustion.)  The quality rating for these factors is
consistent with the rating given by Warn et al. (1990).

       None of the European  or Australian work included emission estimates for fuel oil or
natural gas combustion.
                                          5-3

-------
5.3 MOBILE SOURCES

       The NAPAP program developed NH3 emission factors for mobile sources from a
limited series of test data collected from 1973 to 1980.  Use of these factors resulted in 2.8%
of the NH3 emissions in the 1985 NAPAP inventory.  In the NAPAP documentation, 8 sets of
data are reported.  There is one data set for  diesel, two data sets  for leaded gasoline (for a
1956 Oldsmobile and a 1972 Pontiac, both V-8 engines), and five data sets for unleaded
gasoline.  The five unleaded gasoline data sets include cars with  and without catalytic
converters. The emission factors used in NAPAP are consistent with an analysis of a range
of concern for mobile source emissions of NH3 conducted by the EPA Office of Mobile
Sources.18

       Moller & Schieferdecker (1989) use  the factor of 25 mg NH3(N)/km in their
development of an NH3 emission inventory for the German Democratic Republic (G.D.R.)  As
their source, they cite Bottger et al. (1978).19  It is unclear how these factors were
developed, but because they were  developed so long ago, they could not have included the
test data of Cadle and Mulawa (1980)20 for unleaded gasoline engines with catalytic
converters.

       In  a recent analysis of uncertainties in NH3 emissions in the United Kingdom, Lee and
Bollard (1994) use the NAPAP factors for mobile sources.

       The mobile source emission factors are presented in Table 5-3 and the NAPAP factors
are determined to be the best available; however, these factors are all very uncertain and their
use in an inventory would be of questionable validity.  The ratings presented in Table 5-3 are
consistent with Warn et al. (1990).
5.4 USE OF AMMONIA AND UREA TO REDUCE, CATALYTICALLY OR
NONCATALYTICALLY, NITROGEN OXIDES IN COMBUSTION GASES

       The formation of NOX is a major problem associated with fuel combustion. NOX is
formed when nitrogen and oxygen combine at the high temperatures of combustion, and is a
major contributor, with other pollutants, to urban ozone (smog) problems, and to acid
precipitation. NOX also causes detrimental health and ecological effects. NOX has not been as
amenable to traditional pollution controls as other pollutants, because it is present in low
concentrations in combustion gases.  However, its high impact, with regard to urban ozone
problems and acid rain deposition, has prompted a number of innovative developments in the
control of NOX.

       Two important developments for NOX control in combustion gases are "selective
catalytic reduction" (SCR), and  "selective non-catalytic reduction" (SNCR). Both of these
processes involve the chemical reduction of NOX to elemental nitrogen (N2).  For stationary

                                          5-4

-------
                TABLE 5-3.  MOBILE SOURCE EMISSION FACTORS
Source
Mobile sources -
unleaded gasoline
Mobile sources - leaded
gasoline
Mobile sources - diesel
Moller & Schieferdecker
Emission Factor
(kg/103 liter)
0.075
0.050
0.11
0.218a
Quality
Rating
D
D
E
E
Emission Factor
(lb/103 gallons)
0.63
0.42
0.95
1.82




   (1989)
  "Converted from 25 mg NH3(N)/km to kg/103 liter based on 4.5 km/liter (16.9
  miles/gallon).
source combustion, SCR and SNCR systems use NH3 or urea (an NH3 derivative) as chemical
reducing agents. With either reducing agent, some NH3 remains after the NOX reduction
reaction, and is emitted in the flue gas. This NH3 emission is termed "NH3 slip." The
following sections give more detail on the SCR and  SNCR processes, and on NH3 slip
emissions from these processes.21

5.4.1  Selective Catalytic Reduction

       In SCR systems, NH3 is injected into the combustion flue gas, which is then passed
through a catalyst bed. The NH3 reacts with NOX to produce nitrogen and water in the
following reactions:

                       4 NH3 +  4 NO  + O2  -»  4 N2 + 6 H2O

                          8 NH3  +  6 NO2  -»  7 N2  +  12 H2O

The catalyst lowers the activation energy  of these  reactions, allowing them to proceed at
typical flue gas temperatures.  The  catalyst may consist of precious  metals (platinum or
palladium), base metal oxides (vanadium, titanium, or others), or zeolites (crystalline
aluminosilicates).

       The effectiveness of SCR systems in reducing NOX is  strongly influenced by the NH3-
to-NOx ratio.  Typically, a 1:1  stoichiometry can only achieve an 80 percent reduction of
NOX.  Excess NH3  can produce  greater NOX reductions, but this also results in more NH3 slip.
A number of other factors also affect both the NOX reduction efficiency  and the NH3 slip.
                                          5-5

-------
Most important, the NOX efficiency is reduced and the NH3 slip is increased when the catalyst
condition and the catalyst bed temperature are not optimum.

5.4.2 Selective Non-Catalytic Reduction

       The SNCR process involves the injection of NH3 or urea into the flue  gas without any
catalyst.  Because no catalyst is used, NH3 or urea used in SNCR must be injected into the
flue  gas at higher temperatures.  The reactions of NH3 with NOX have been presented above.
Urea ((NH2)2C=O) reacts with NOX and oxygen to produce elemental nitrogen, water, and
carbon dioxide (CO2).  (The reaction of urea with NOX is not well understood because of the
complexity of urea pyrolysis and subsequent free radical reactions.) However, urea also
decomposes to NH3 and to other products at elevated temperatures, producing NH3 slip.

       As in SCR, the NH3-to-NOx ratio has a strong influence on NOX reduction  efficiency.
A 1:1 ratio results in NOX reductions of less than 40 percent, while a 2:1 ratio can produce up
to 60 percent reduction in NOX.  Again, there is a trade-off between NOX reduction efficiency
and NH3 slip.

5.4.3 Ammonia Emissions and Emission Factors

       In analyzing alternative control technologies for NOX, EPA's Emission Standards
Division compiled performance  data on a number of SCR and SNCR systems. In addition,
NH3 slip emission factors are available  in the California  "Hot Spots" Air Toxics Emissions
Data System (ATEDS) for several natural gas combustion facilities equipped with SCR.
Table 5-4 summarizes NH3  slip  data from EPA control alternative analyses and the ATEDS
system.22'23'24 As the table shows, NH3  slip is extremely variable, ranging from less than
1 ppm in the flue gas up to 100 ppm.  Manufacturers typically cite NH3 slip values of 5 to  10
ppm for SCR, and 20 to 30 ppm for SNCR.25 For the purposes of emission factor
development, an average NH3 slip of 15 ppm was used for SCR systems, and 30 ppm for
SNCR systems.  These values represent a synthesis of manufacturers'  information and the
data in Table 5-4.

       Table 5-5 gives NH3 emission factors for SCR and SNCR, as applied to various fuel
types.  The emission factors are linked to the appropriate SCCs and AIRS  control device
codes.  AIRS control code 65 applies to SCR, and AIRS control code 32,  "Ammonia
Injection," applies to SNCR with NH3.  There is presently no control code for urea injection.
All of the NH3 slip emission factors for SCR and SNCR are rated as C.  For coal, oil, and
other fuels, there are a few  good sources of data, which show considerable variability. For
natural gas SNCR systems,  more data exists, but the variability of that data is extremely high.
Variability is much lower for the natural gas SCR installations listed in the California ATEDS
data base, but no  information is available from the data base on the conditions existing during
the NH3 testing.
                                          5-6

-------
          TABLE 5-4.  SUMMARY OF AMMONIA SLIP DATA FOR SCR
                           AND SNCR INSTALLATIONS


Control
SCR














SNCR














Fuel/
system
Coal

Oil

Gas










Coal
(FBC)


Oil

Gas





Wood
MSW


Reagant
NH3
NH3
NH3
NH3
na
na
na
na
na
na
na
na
na
na
na
NH3
NH3
Urea
Urea
Urea
Urea
Urea
Urea
Urea
Urea
Urea
NH3
Urea
Urea
Generating
Capacity
(MW)
1
1
1
107
na
na
na
na
na
na
na
na
na
na
na
25
57
na
na
110
185
110
156
333
342
345
345
na
na
NOX
reduction
(percent)
80
70 - 80
60 - 80
90
na
na
na
na
na
na
na
na
na
na
na
na
na
57
70
42
38 -48
35 - 50
26 -40
7 - 14
23 - 36
30
30
25 - 50
41-70
Ammonia
slip
(ppm)
<1
1 -20
<20 - <50
10 -40
20
13
28
16
22
18
20
28
12
5
8
28
<20
<18
<10
3 -75
5 - 10
10 - 50
13 - 18
6 - 9
7 - 17
80 - 110
50 - 110
<10 - <40
<5 -22


Reference
22
22
22
22
24
24
24
24
24
24
24
24
24
24
24
22
22
23
23
22
22
22
22
22
22
22
22
23
23
      Table 5-5 also gives activities for combustion sources controlled by SCR and SNCR,
as taken from the 1990 Interim Emissions Inventory.26  It should be pointed out that the
control information for SCR and SNCR systems in the Interim Inventory actually dates back
to the 1985 NAPAP inventory.  As a result the activities are expected to be understated.  In
fact, reported  SCR and SNCR NH3 emissions in the California Hot Spots are  about 68 Mg
                                        5-7

-------
(75 tons) per year, higher than the national NH3 emissions given by the Interim Inventory
activity data. Further, SCR and SNCR are expected to expand drastically over the next two
decades as a result of the 1990 Clean Air Act Amendments.

5.5 BIOMASS BURNING

       Nitrogen, as an essential ingredient of proteins, is present in all biomass.  For instance,
the average  concentration of nitrogen in wood is about 0.1 percent.27  This nitrogen is in a
"reduced" chemical state, typically as amides (R— (C=O)—NH—R'), and amines (R—NH2). The
equilibrium  products of this fuel nitrogen under combustion conditions are elemental  nitrogen
(N2) and nitrogen oxides (NO and NO2, or NOX). However, because it is initially in a
chemically reduced state, and because biomass burning typically occurs under poor mixing
conditions, the biomass nitrogen can be released as NH3.

       Lee and Atkins (1994)28 conducted a field measurement program of NH3 and
ammonium aerosol during straw and stubble burning. They concluded that NH3 emissions
over the six  to eight week period during which this burning typically occurs were calculated
to be 27% of the total U.K. emissions over the equivalent period in 1981, and 7% in 1991.
The decline  is due to changes in agricultural  practices in response to impending U.K.
legislation.

       Denmead (1990) developed an NH3 budget for Australia and included a method for
estimating NH3 emissions from biomass burning that is dependent upon an emission ratio for
NH3 relative to the increase in CO2.  Denmead (1990) uses an emission ratio of l.SxlO"3
mole/mole.  In order to calculate emissions, data on carbon released in vegetation fires in
Australia was used with the ratio of 0.1 mole CO/mole CO2.  This led to the conclusion  that
biomass burning may contribute 1/16 to 1/6 of the NH3  released in Australia.

       Schlesinger and Hartley (1992) compiled a global budget for atmospheric NH3 in
which they estimated that biomass burning may contribute up to twelve percent of the total
annual global flux.29 The uncertainty of these estimates is very high, and additional research
into the primary references is needed prior to the establishment of emission factors.

5.6 RECOMMENDED COMBUSTION AMMONIA EMISSION FACTORS AND
CLASSIFICATION CODES

       Table 5-6 summarizes the emission factors for combustion sources and presents the
applicable point, area, and mobile source classification codes.
                                          5-8

-------
                           TABLE 5-5.  SCR AND  SNCR AMMONIA EMISSION FACTORS
Control technique/
fuel
SCR





SNCR




Coal

Oil



Gas

Wood
Coal

Oil



Gas
Wood
NH3
slip
(ppm)
15

15



15

15
30

30



30
30
Emission
factor
0.155

0.17



146.

0.155
0.315

0.35



288.
0.315
Emission
Factor Units
kg/Mg

kg/103 liters



kg/106 m3

kg/Mg
kg/Mg

kg/103 liters



kg/106 m3
kg/Mg
Control
device
code
65

65



65

65
32

32



32
32
Applicable SCCs
lOlOOlxx, 101002xx, 101003xx, 102001xx,
102002xx, 102003xx, 103001xx, 103001xx,
103003xx, 10500102, 10500202
101004xx, lOlOOSxx, 102004xx, 102005xx,
103004xx, 103005xx, 10500105, 10500205,
201001xx, 201009xx, 202001xx, 202003xx,
20200401, 20200501, 202009xx, 203001xx,
20300301
101006xx, 102006xx, 103006xx, 10500106,
10500206, 201002xx, 202002xx, 203002xx
101009xx, 102009xx, 103009xx
lOlOOlxx, 101002xx, 101003xx, 102001xx,
102002xx, 102003xx, 103001xx, 103001xx,
103003xx, 10500102, 10500202
101004xx, lOlOOSxx, 102004xx, 102005xx,
103004xx, 103005xx, 10500105, 10500205,
201001xx, 201009xx, 202001xx, 202003xx,
20200401, 20200501, 202009xx, 203001xx,
20300301
101006xx, 102006xx, 103006xx, 10500106,
10500206, 201002xx, 202002xx, 203002xx
101009xx, 102009xx, 103009xx
Factor
rating
C

C



C

C
C

C



C
C
Emission Factor
(Ib/SCC Unit)
0.31 Ib/ton

1.4 lb/1000 gal



9. 1 Ib/MMscf

0.31 Ib/ton
0.63 Ib/ton

2.9 lb/1000 gal



18 Ib/MMscf
0.63 Ib/MMscf
Activity
(SCC
units)






2,249




33,461





Estimated
emissions
(Mg/yr)






0.91




44.





"Activity levels are taken from the 1990 Interim Inventory. However, the Interim Inventory values are actually projections from the
1985 NAPAP inventory, and are believed to be underestimates.

-------
TABLE 5-6. RECOMMENDED EMISSION FACTORS FOR COMBUSTION SOURCES
Source
Source Classification Codes Emission Factor Factor
(metric units) Rating
Coal Combustion lOlOOlxx, 101002xx, 101003xx, 102001xx, 102002xx, 0.00028 kg/Mg E
102003xx, 10300 Ixx, 103002xx, 103003xx, 10500102,
10500202
21-99-001-000, 21-99-002-000, 21-99-003-000
Fuel Oil Combustion 101004XX, 101005xx, 102004xx, 102005xx, 103004xx, 0.096 kg/103 liters E
103005xx, 10500105, 10500205, 21-99-004-000, 21-99-005-
000
Natural Gas 101006xx, 102006xx, 21-01-006-xxx, 21-02-006-xxx 51. kg/106 m3 C
Combustion - Utility
and Industrial Boilers
Natural Gas
Combustion -
Commercial Boilers
Mobile Sources -
Leaded Gasoline*
Mobile Sources -
Diesel
SCR - Coal
SCR - Oil
103006xx, 21-03-006-xxx 7.8 kg/106 m3 C
22-01-xxx-xxx 0.050 kg/103 liter D
22-30-xxx-xxx 0.11 kg/103 liter E
lOlOOlxx, 101002xx, 101003xx, 102001xx, 102002xx, 0.155 kg/Mg C
102003xx, 10300 Ixx, 103002xx, 103003xx, 10500102,
10500202
101004xx, 101005xx, 102004xx, 102005xx, 103004xx, 0.17 kg/103 liters C
103005xx, 10500105, 10500205, 201001xx, 201009xx,
202001xx, 202003xx, 20200401, 20200501, 202009xx,
203001xx, 20300301
Emission Factor
(english units)
0.565 lb/103 ton
0.8 lb/103 gal
3.2 lb/106 ft3
0.49 lb/106 ft3
0.42 lb/103
gallons
0.95 lb/103
gallons
0.31 Ib/ton
1.4 lb/103
gallons
                              (Continued)

-------
                                                    Table 5-6 (Continued)
        Source
Source Classification Codes
Emission Factor    Factor    Emission Factor
 (metric units)     Rating     (english units)
SCR - Gas


SCR - Wood

SNCR - Coal


SNCR - Oil



SNCR - Gas


SNCR - Wood
101006xx, 102006xx, 103006xx, 10500106,  10500206,
201002xx, 202002xx, 203002xx

101009xx, 102009xx, 103009xx

lOlOOlxx, 101002xx, 101003xx, 102001xx,  102002xx,
102003xx, 10300 Ixx, 103002xx, 103003xx,  10500102,
10500202

101004xx, 101005xx, 102004xx, 102005xx,  103004xx,
103005xx, 10500105, 10500205, 201001xx,  201009xx,
202001xx, 202003xx, 20200401, 20200501,  202009xx,
203001xx, 20300301

101006xx, 102006xx, 103006xx, 10500106,  10500206,
201002xx, 202002xx, 203002xx

101009xx, 102009xx, 103009xx
                                                                                146. kg/106 m3


                                                                                0.155 kg/Mg

                                                                                0.315 kg/Mg
                                                                               0.3 15 kg/Mg
                                                            C


                                                            C

                                                            C
                                                                               0.35 kg/103 liters    C
                                                                               288 kg/106 m3       C
                                                            C
                            9.1 Ib/MMscf

                             0.31 Ib/ton

                             0.63 Ib/ton
                                                                        2.9 lb/103
                                                                         gallons
                                                                       18 Ib/MMscf
                           0.63 Ib/MMscf
"Emission factors for leaded gasoline are not presented because leaded gasoline is almost completely phased out and the source category
classifications for the U.S. do not distinguish between leaded and unleaded gasoline.

-------
                          REFERENCES FOR SECTION 5

1.     Personal communication between Rebecca Battye, EC/R Incorporated and Bruce
      Polkowsky, U.S. Environmental Protection Agency.  July 21, 1994.

2.     Asman, W. A.H.  Ammonia Emission in Europe:  Updated emission and emission
      variations. National Institute of Public Health and Environmental Protection.
      Bilthoven. May 1992.

3.     Bauer, C.F. and A.W. Andren.  Emissions of Vapor-Phase Fluorine and Ammonia
      from the Colombia Coal-Fired Power Plant. EPA/600/J-85/274.  PB86-157757
      Environmental Science  and Technology, 19(11):1009-1103, 1985.

4.     Warn,  T.E., S. Zelmanowitz, and M. Saeger. Development and Selection of Ammonia
      Emission Factors for the 1985 NAPAP Emissions Inventory.  EPA-600/7-90-014.
      Prepared for the National Acid Precipitation Assessment Program (NAPAP) by the
      U.S. Environmental Protection Agency, Office of Research and Development,
      Washington, D.C.  June 1990.

5.     Misenheimer, D.C., T.E. Warn, and S. Zelmanowitz.  Ammonia Emission Factors for
      the NAPAP Emission Inventory. EPA-600/7-87-001.  U.S. Environmental Protection
      Agency, Office of Research and Development, Washington, DC.  January 1987.

6.     Lee, D.S. and J.W.S. Longhurst.  Estimates of Emissions of SO2, NO,,  HCl,  and NH3
      from a Densely Populated Region of the UK. Environmental Pollution 79:37-44.
      Great Britain.  1993.

7.     Subcommittee on Ammonia, Ammonia: Medical and Biological Effects of
      Environmental Pollutants.  Subcommittee on Ammonia, Assembly Life Sciences NRC
      USA, University Park Press, Baltimore. 1979.

8.     Buijsman, E. Historical Trends in Ammonia Emission in Europe (1870-1980).  Report
      R-86-9, Institute for Meteorology and Oceanography,  State University  of Utrecht, The
      Netherlands.  1986.

9.     Moller, D., and H. Schieferdecker.  Ammonia Emission and Deposition ofNHx in the
      G.D.R., Atmospheric Environment,  Volume 23, Number 6:1187-1193.   Great Britain.
      1989.

10.    Kruse, M., H.M. ApSimon, and J.N.B. Bell. Validity and Uncertainty in the
      Calculation of an Emission Inventory for Ammonia Arising from Agriculture in Great
      Britain.  Environmental Pollution. 56:237-257. Great Britain.  1989.

11.    Lee, D.S., and G.J. Dollard.  Uncertainties in Current Estimates of Emissions of
      Ammonia in the United Kingdom.  Environmental Pollution,  (in press in 1994).
                                        5-13

-------
12.     Geadah, M.L. National Inventory of Natural and Anthropogenic Sources and
       Emissions of Ammonia (1980).  EPA 5/IC/l Environment Canada, Ontario.  1985.

13.     Denmead, O.T.  An Ammonia Budget for Australia. Australian Journal Soil Resources
       28: 887-900.  Australia.  1990.

14.     Robinson, E.,  and Robbins, R.C. Emissions, concentrations and fate of gaseous
       atmospheric pollutants.  In "Air Pollution Control, Part 2".  (Ed.  W. Strauss.) pp. 1-93.
       (Wiley Intersciences:New York.)  1972.

15.     Muzio, LJ.  and J.K. Arand. Homogeneous Gas Phase Decomposition of Oxides of
       Nitrogen. Electric Power Research Institute, 1976.  pp. 60-61, C-12.

16.     Magill, P.L. and R.W. Benoliel.  Air Pollution in Los Angeles County.  Industrial and
       Engineering Chemistry.  44:1347-1351.  1952.

17.     Cass, G.R. et al.  The Origin of Ammonia Emissions to the Atmosphere in an Urban
       Area.  Environmental Quality Laboratory, California Institute of Technology,
       Pasadena, CA. 1982.

18.     Garbe, RJ.  Determination of a Range of Concern for Mobile Source Emissions of
       Ammonia.  EPA/AA/CTAB/PA/81-20.  U.S. Environmental Portection Agency, Office
       of Mobile Source Air Pollution  Control, Ann Arbor, MI.  August 1981.

19.     Bottger A., P.H. Ehhalt  and G. Gravenhorst. Atmospharische Kreislaufe von
       Stickoxiden und Ammoniak.  Berichte Kernforschungsanlage Julich (F.R.G.) No. 1958.
       1978

20.     Cadle, S.H.  and P. A. Mulawa.  Low Molecular Weight Aliphatic Amines in Exhaust
      from Catalyst-Equipped Cars.  Environmental  Science and Technology,  14(6):721,
       1980.

21.     Alternative Control Techniques Document — NOX Emissions from Utility Boilers.
       EPA-453/R-94-023, U.S. Environmental Protection Agency, Research Triangle Park,
       North  Carolina.  March  1994.  pages 5-97 through 5-141.

22.     Reference 21. pp 7-24 through 7-27.

23.     Alternative Control Techniques Document — NOX Emissions from Industrial/
       Commercial/Institutional Boilers.  EPA-453/R-94-022, U.S. Environmental Protection
       Agency, Research Triangle Park, North Carolina. March 1994.  pg. 7-10.

24.     Letter  from Richard Bode, Manager, Special Pollutants Emission Inventory Division,
       Technical Support Division, California Air Resources Board, to Rebecca Battye, EC/R
       Incorporated.  May  16, 1994. Transmitting data from the California Air Toxics Hot
       Spots program.

                                        5-14

-------
25.     Garg, A.  Trimming NO
-------
                                      SECTION 6

                            MISCELLANEOUS SOURCES

       Additional sources of NH3 emissions include, at a minimum, human breath and
perspiration, publicly owned treatment works (POTW's), non agricultural soils, and
refrigeration.  Although these sources are known to contribute, the emission factors for them
are very uncertain.  Asman (1992)1 discussed many of these sources and provided emissions
estimates for  some categories, but did not include these  sources in his recent inventory of
NH3 emissions in Europe. This exclusion was either due to their contribution being too small,
too uncertain, or due to the geographical location of the specific emission source being
unknown, making it impossible to incorporate the source into his gridded inventory. Of these
sources of NH3, nonagricultural or undisturbed soils, according to some researchers, have the
potential  of emitting up to 40 to 50% of the NH3 measured in the atmosphere.

6.1 HUMAN BREATH AND PERSPIRATION

       The NH3 emission factors for humans used in recent inventories vary widely, ranging
from 0.25 to  1.3 kg NH3/person/year.  Asman (1992) notes that using either factor to calculate
emissions from humans still produced an insignificant amount of NH3 emissions, when
compared to those estimated for agricultural sources.

       At the low end  of this estimated range, emission factors for human breath and
perspiration were prepared by Warn et al. (1990)2 for NAPAP, although NH3 emissions were
not included in the 1985 NAPAP emission inventory. The NAPAP report presented human
breath  emission factors of 4.1 kg/103 smokers and 5.4 kg/103 non-smokers (9.1 lb/103 smokers
and 12.0  lb/103 non-smokers).  An additional 0.82 kg/103 smokers (1.8 lb/103 smokers) is
added for the NH3 released from  the cigarette.  The NAPAP NH3 emission factors for humans
are predominantly from perspiration, which is estimated at 0.25 kg/person (0.55 Ib/person).
Emission factors for smokers and non-smokers are 0.25  kg NH3/person (0.56 Ib/person).  Cass
et al. (1982)3 also used an emission factor of 0.25 kg NH3-N/person/year.

       At the high end of the estimates,  Moller and Schieferdecker (1989)4 used an emission
factor of 1.3 kg NH3-N/person/year in a recent inventory of NH3 emissions in the G.D.R.
This factor is based on an estimated nitrogen production of around 5  kg NH3-N/person/year,
and assumes an NH3 release of 25 percent.

       Healy et al. (1970)5  is quoted in one source as using a value of 0.31 kg NH3-
N/person/year, and is quoted in another source as using a factor of 0.54 kg NH3-
N/person/year.

       Atkins and Lee  (1993)6 recently re-examined data collected in  1978 by Harwell
Laboratory.  Indoor NH3  concentrations were measured in a number of homes of Harwell
Laboratory staff, using  a passive  diffusion tube sampler.  The NH3 was collected on an

                                          6-1

-------
absorbing surface of sulfuric acid-impregnated glass-fibre filters, and the quantity was
determined spectrophotometrically by the phenol/hypochlorite (indophenol blue) method.
Using calculated sampling rates, the diffusion tubes were found to give atmospheric NH3
levels in satisfactory agreement with those found using a simple filter-bubbler technique.
This method is not subject to interference from particulate ammonium compounds.

       Atkins and Lee (1993) report mean NH3 concentrations of 38.7 |ig/m3 in a kitchen,
37.4 |ig/m3 in  a living room, and 32.5 |ig/m3 in a bedroom. These values do not compare
particularly well with other measurements of Sisovic et al. (1987),7 and Bracer et al.
(1989),8 which ranged from 23 to 280 |ig/m3 and 3 to 23 |ig/m3, respectively.  Atkins and
Lee (1993) calculate that an expected household concentration, based on a mid-range of
available emission factors of 1 kg NH3/person/year, should be 431 |ig/m3, which is  an order
of magnitude higher than the values measured.

       Lee and Bollard (1994)9 summarized all of the available information on NH3 from
humans and noted that the research has documented a range of 0.25 to 1.3 kg
NH3/person/year.  They also noted that additional  research is ongoing and will  soon be
published.

       Table 6-1  summarizes the available emission factors for human sources.  Based  on the
information presented, it seems likely that the factor of 1.3 kg NH3/person/year is too high,
therefore, until new research is published, the NAPAP factor of 0.25 kg/person is
recommended for use.  An emission factor rating of E is assigned to the factor, based on the
rating for human perspiration that was provided in the NAPAP report.

6.2 PUBLICLY OWNED TREATMENT  WORKS

       In the mid 1980's, Allen et al. (1988)10 measured ground-level concentrations of NH3
and ammonium (NH4+), using filter packs, at nineteen sites within a 35-km radius of
Colchester, U.K.  The sampling  sites were selected to verify the influence of possible sources
on NH3 concentrations.  The six sites included livestock farms (sheep at one site, pigs at one
site, turkeys kept seasonally at both sites, and sheep kept seasonally at a third site), landfill
sites, sewage treatment works, an arable farm,  urban sites, and a marine  site. Other samplers
were sited at typical rural locations without obvious influences of specific NH3 sources.
Although the livestock farms showed pronounced  elevations of NH3, the sewage treatment
plant showed concentrations that were not greatly  different than the  other non-agricultural
sites, leading Allen  et al. to  conclude that sewage treatment is  a minor or insignificant source
of NH3 emissions. The water treatment plant was  of the percolating filter type, where the
wastewater is trickled downwards as a part of the  purification process, rather than the plant
being of the more common,  larger, activated sludge type of treatment plant.  Because of the
work of Allen et al.  (1988),  emissions of NH3  during the normal operation of waste water
treatment plants have not been considered as a significant source in the more recent emission inventories.
                                           6-2

-------
      TABLE 6-1.  AMMONIA EMISSION FACTORS FOR HUMAN SOURCES
Source Emission Factor Factor
(kg/person/year) Rating
NAPAP - Smokers
NAPAP - Nonsmokers
NAPAP - Cigarette smoke
NAPAP - human perspiration
Buijsman (1984)
Atkins and Lee (1993)
Moller & Schieferdecker (1989)
Cass et al. (1982)
Healy et al. (1970)
Lee and Dollard (1994)
0.0041 D
0.0054 D
0.00082 C
0.25 E
0.3
1
1.3
0.25
0.31 to 0.54
0.25 to 1.3
Emission Factor
(Ib/person)
0.0091
0.012
0.0018
0.55
0.7
2.2
2.9
0.55
0.7 to 1.2
0.55 to 2.9
       Buijsman et al. (1987)11 included sewage sludge applied to land as a minor source of
atmospheric NH3, based on data reported by King (1973)12 and Beauchamp (1978).13
Kruse et al. (1989)14 developed an NH3 emission inventory for Great Britain, and  stated that
sewage may be another potentially important source of NH3, although it was not included in
the inventory.  Asman (1992) states that sewage sludge  is a source of NH3 emissions, but that
emissions are very uncertain and not very important.

       Recently, Lee et al.  (1992)15 reported preliminary data on NH3 concentrations in the
vicinity of an activated sludge sewage treatment plant.  Many of the larger sewage treatment
plants use the activated sludge process. In the activated sludge process, large solids are
removed by sedimentation.  Bubbles of air are then blown up through the solution, and are
seeded with the sludge at a pH of approximately 7 to 8.  During this process, NH3 is oxidized
to NO2" and NO3".  It is likely that some of the ammoniacal nitrogen will be lost to the
atmosphere as NH3 gas. The fraction of NH3 lost to the atmosphere is dependent  upon the
pH of the solution.  Lee et al. (1992) have preliminary results  of concentrations of 12 to 100
|ig/m3,  which is substantially higher than the concentrations measured by Allen et  al. (1988),
of 3 |ig/m3 near a percolating filter waste water treatment  plant.

       The 1985 NAPAP emission inventory utilized a  POTW emission factor of 2.2 kg/106
liters (19 Ib NFL/106 gallons) treated, resulting in an emission  estimate of 6.6% of the  1985
NAPAP emission inventory.  The NAPAP  factor was developed based on the 1984 Needs
Survey, which included influent and effluent NH3 concentrations for over 850 wastewater

                                          6-3

-------
treatment facilities nationwide, and was also developed based on research on NH3 stripping
from treatments plants (Warn et a/., 1990).

       Recent analysis of the Hot Spot Toxic Inventory for the State of California provided
NH3 emission rates that were reported for several plants.16  It should be noted that some of
names of the emission points in the California data do not  match well with the SCCs chosen,
resulting in confusing emission factors.  Specifically,  an aerobic digester was coded as  an
entire plant, and a sludge thickener was coded as an aeration tank.  The NAPAP factor and
the factors reported in California are summarized in Table  6-2.  Until the data from Lee et al.
(1992) are published, the NAPAP values are recommended for continued use.  The emission
factor for POTWs is  assigned a quality rating of E which is consistent with the rating
provided by Warn et al.  (1990).

            TABLE 6-2. AMMONIA EMISSION FACTORS FOR POTWS
Source
(SCC)
NAPAP
Emission Factor
(kg/106 liters treated)
Avg Max Min
2.2
Emission Factor
(lbs/106 gallons treated)
Avg Max Min
19
    5-01-007-01

    California - Entire plant"          1.93        5.39    0.012           16.1     45     0.099
    5-01-007-01

    California - Primary settling       0.00023                             0.0019
    5-01-007-02

    California - Aeration3            14          29      0.00066        120      240     0.00552
    5-01-007-04

  a The throughput for an entire plant is considerably higher than the throughput of an aeration tank
  resulting in a higher emission rate for the aeration tank.
6.3  NON-AGRICULTURAL SOILS

       There is a great deal of uncertainty surrounding NH3 emissions from undisturbed land
or nonagricultural plants and soils, because of the ability of soils and plants to act as both
sources and sinks of NH3. Due to this uncertainty,  Asman (1992) did not include this
potential source of emissions in his recent inventory of NH3 emissions in Europe. NAPAP
did not include undisturbed land in the 1985 emission inventory. Erisman (1989)17 noted a
range of 0.009 g NH3/m2/year to 0.03 g NH3/m2/year (0.09 kg NH3/ha/year to 0.3 kg
N/ha/year) for natural  soils, and did not include natural NH3 emissions due to the large
uncertainty in these values.
                                            6-4

-------
       Buijsman et al. (1987) discussed natural NH3 emissions from undisturbed land. Using
a flux of 10 |ig/m2/h, which was within the range of various researchers cited, he estimated a
natural annual NH3 flux of 0.75 gigagrams (Gg) NH3, which is far exceeded by the
anthropogenic emissions (6.4 Gg NH3) and, therefore, NH3 emissions from undisturbed land
are not included in the final inventory. Lee & Longhurst (1993)18 used the  factor from
Buijsman (1986)19 of 0.009 g NH3/m2/year for vegetated land in their NH3 inventory for
densely populated regions of the United Kingdom.  Moller &  Schieferdecker (1989) use an
emission factor for arable  land (agricultural and forests) of 0.03 g NH3/m2/year (3 kg
NH3(N)/ha/year) in their NH3 inventory for the G.D.R.  The value of 0.03 g/m2/yr (3 kg
N/ha/yr) may originate with Dawson (1977)20 who apparently developed one of the first
models for NH3 emission estimates from undisturbed lands.

       Denmead (1990)21  concluded that NH3 emissions from natural fields  were the most
important source of NH3 in Australia, providing 47% of the NH3.  He discussed soils, plants,
and plant communities, and used measurement in an ungrazed, unfertilized,  grass-clover
pasture to estimate emissions from uncultivated land. He estimated NH3 emissions  by
assuming that 30  g N/ha/day are produced in  a 6-month period (0.55  g N/m2/year, assuming
183 days/year) over the 164 million hectares of forest and uncultivated country in the humid,
sub-humid  and monsoonal zones delineated in the Atlas of Australian Resources. He
estimated that NH3 emission rates were negligible in the drier zones.

       In a recent study of the uncertainties in current estimates of NH3 in the United
Kingdom, Lee and Dollard (1993) note that Metcalfe et al. (1989)22 suggested that the
emissions of NH3 may be  as high as  5 g/m2 (50 kg/ha).

       Schlesinger &  Hartley (1992)23 compiled research on the soil flux  of NH3 from the
world's undisturbed ecosystems, and derived a global estimate for the total flux of NH3 to the
atmosphere from  all sources.  Studies on NH3 from undisturbed ecosystems included data
obtained by chamber measurements, as well as regional estimates from atmospheric
concentration gradients. Problems with both methods are acknowledged.  Hourly rates of
NH3 volatilization range over four orders of magnitude, with the highest values found in  some
grassland ecosystems.  Much of the variation  is believed to be due to differences in soil
temperature and moisture during the period of measurement. Many of the measurements
were taken in midday and/or the summer season when the volatilization rates are highest;
therefore, extrapolation of these values to provide annual estimates would produce high
estimates.  Schlesinger & Hartley (1992) limited the NH3 volatilization losses in their
estimations to 20% of annual net mineralization of soil  nitrogen, because this is the average
loss of NH3 during fertilizer applications.

       Table 6-3  summarizes NH3 emission rates that have  been cited in the literature. Due
to the extensive review provided by Schlesinger and Hartley (1992), their emission  factors are
recommended for use.  All four of the factors from Schlesinger and Hartley (1992) are
assigned an emission factor rating of E.
                                          6-5

-------
 TABLE 6-3.  AMMONIA EMISSION FACTORS FOR NON-AGRICULTURAL SOILS


              Source                 Emission Factor       Factor    Emission Factor
                                      (g NH3-N/m2)a        Rating     (Ib NH3/acre)

   Lee and Longhurst (1993)                      0.009                          0.97

   Moller & Schieferdecker                      0.03                           0.32
   (1989)

   Metcalfe et al. (1989)                         0.5                            5.4

   Denmead (1990)                              0.56                           6.0

   Schlesinger and Hartley               0.1 to 1.0            E          1 to 10.
   Temperate forest and
   Woodland & Shrubland

   Schlesinger and Hartley              0.25 to 0.75           E         2.7 to 8.1
   Tropical Savanna

   Schlesinger and Hartley              0.01 to 1.0            E         0.1 to 10.
   Temperate Grassland

   Schlesinger and Hartley              0.01 to 0.25           E         0.1 to 2.7
   Desert Scrub

  aA hectare is equal to 10,000 m2 or 2.471  acres.


6.4 USE OF AMMONIA AS A REFRIGERANT

       Ammonia is used extensively as a refrigerant in large industrial and commercial
installations. It has the advantages of a high heat of vaporization and a favorable pressure-
volume relationship. However, it also has the disadvantage of being toxic and corrosive to
some materials, most notably copper.24 The  consumption of NH3 for refrigeration
applications in the U.S. is estimated at 270,000 Mg/year.25

       It is  assumed that all of the NH3 used in refrigeration is ultimately emitted to the
atmosphere. Because NH3 refrigeration is a  mature technology (its use in this application
precedes that of Freons), it is further assumed that  there is a steady state relationship between
NH3 refrigerant consumption and emissions.   Therefore, the annual emission  rate for NH3
from refrigeration is also estimated at 270,000 Mg/year.

       There were no emission factors for NH3 from refrigeration in the literature. Because
NH3 is most commonly used in large commercial or industrial  refrigeration systems,
emissions of NH3 refrigerant are probably best estimated using employee statistics which are

                                           6-6

-------
readily available and allow for NH3 refrigerant usage to be apportioned to the State and
county level. Refrigeration is probably used in many industries, however, the knowledge is
incomplete and fuurther research into the development of an NH3 emission factor for
refrigeration is recommended for future research.  Intuitively it is assumed that the majority
of the industrial and commercial refrigeration is in the Major SIC group 20, Food and
Kindred Products.  Using a national employment of 1,453,000 for SIC 20xx, the average
emission factor for NH3 used as a refrigerant is 187 kg/employee (413 Ib/employee).  This
emission factor is given a rating of E, because the factor is derived from a national level
material balance, and not on test data.

6.5 AMMONIA SPILLS

       Under Section 302 of the Superfund Amendments and Reauthorization Act, accidental
releases of NH3 exceeding 45 kg (100 pounds) must be reported to the National Response
Center, at the U.S. Coast Guard. The reports must contain the nature and amount of the
release, the cause,  the location,  the responsible party, and other information.  The National
Response Center maintains these release reports in a computerized data base.

       Release reports for NH3  were obtained from the National Response Center for 1991
through early 1994.26  During this period, a total of 1648 releases to the atmosphere  were
reported.  The largest reported release was 295 Mg (325 tons) and the average release was 1.5
Mg (1.6 tons).  Table 6-4 summarizes release data by year and by the type of vessel from
which the spills originated.

       The NH3 emitted  through these spills was primarily from fixed storage, and was the
result of spills from refrigeration units. These data could be processed to provide county-
level totals reported through the area source classification code 28-30-000-000 Miscellaneous
Area Sources - All Catastrophic/Accidental Releases - Composite.  Including the spills in an
inventory effort would, however, double count the emissions from refrigeration sources;
therefore, an emission factor is  not being presented for this category of emissions.

6.6    RECOMMENDED AMMONIA EMISSION FACTORS FOR MISCELLANEOUS
       SOURCE CATEGORIES

       Table 6-5 summarizes the NH3 emission factors for the miscellaneous source
categories discussed in this section. It should be emphasized that all of these emission factors
have a quality rating of E and are very uncertain.   Of the source categories discussed, the
NH3 emissions from nonagricultural lands have the potential  for introducing the largest
uncertainty into an emission inventory development effort.
                                           6-7

-------
    TABLE 6-4.  SUMMARY OF ACCIDENTAL RELEASES OF AMMONIA

                          Ammonia releases reported to National Response Center (Mg)
        Source               1990            1991            1992            1993
Fixed storage                   161.5         1,014.0           334.4            498.2
Pipeline                       206.0             0.6              0.3              0.5
Highway vehicles               25.4            14.4             22.6             54.6
Marine vessels                   0.0             0.1              0.2              0.0
Railroads                        1.0             1.3              0.3              0.1
Unknown                       1.5             3.1              0.2              4.7
        Totals                 395.4         1,033.5           358.0            558.1
                                         6-8

-------
                        TABLE 6-5.  RECOMMENDED EMISSION FACTORS FOR
                                       MISCELLANEOUS SOURCES
Classification
Code
28-10-010-000
5-01-007-01
26-30-000-000

27-01-001-000

27-01-470-000


27-01-240-000


27-01-450-000

23-02-080-002

Description
Humans
POTWs
Wastewater treatment -
Composite
Natural sources - Biogenic -
plants - forests - Composite
Natural sources - Biogenic -
plants - Tropical savannah -
Composite
Natural sources - Biogenic -
plants - Vegetation/grassland -
Composite
Natural sources - Biogenic -
plants - desert scrub - Composite
Food & Kindred Products -
Misc. - Refrigeration
Emission Factor
(kg NH3/unit)
0.25
2.2


0.1 to 1.0

0.25 to 0.75


0.01 to 1.00


0.01 to 0.25

187

Unit
person
106 liters


g NH3(N)/m2

g NH3(N)/m2


g NH3(N)/m2


g NH3(N)/m2

kg/employee

Factor
Rating
E
E


E

E


E


E

E

Emission Factor
(Ib NH3/SCC or
AMS unit)
0.55
19


1 to 10

2.7 to 8.1


0.1 to 10.


0.1 to 2.7

413

Estimated annual
emissions (Mg)
62,500a
107,000b


c

c


c


c

270,000

aBased on a U.S. population of 250 million people.
bBased on annual estimate of 12.4 x 1012 gallons treated.
°Unknown.

-------
                          REFERENCES FOR SECTION 6

1.     Asman, W.A.H.  Ammonia Emission in Europe:  Updated emission and emission
      variations. National Institute of Public Health and Environmental Protection.
      Bilthoven. May 1992.

2.     Warn, T.E., S. Zelmanowitz, and M. Saeger.  Development and Selection of Ammonia
      Emission Factors for the 1985 NAPAP Emissions Inventory. EPA-600/7-90-014.
      Prepared for the National Acid Precipitation Assessment Program (NAPAP) by the Us.
      Environmental Protection Agency,  office of Research and Development, Washington,
      DC.  June 1990.

3.     Cass, G.R. et al.  The Origin of Ammonia Emissions to the Atmosphere in an Urban
      Area.  Environmental Quality Laboratory, California Institute of Technology,
      Pasadena, CA.  1982.

4.     Moller, D., and H. Schieferdecker.  Ammonia Emission and Deposition ofNHx in the
      G.D.R.  Atmospheric Environment Volume 23, Number 6:1187-1193.  Great Britain.
      1989.

5.     Healy, T.V., H.A.C. McKay, A.  Pilbeam, and D. Scargill. Ammonia and ammonium
      sulphate in the troposphere  over the United Kingdom.  J. Geophys. Res., 75, 2317.
      1970.

6.     Atkins, D.H.F. and D.S. Lee.  Indoor Concentrations of Ammonia and the Potential
      Contribution of Humans to Atmospheric Budgets.  Atmospheric Environment  Volume
      27A, Number 1:1-7.  Great  Britain.  1993.

7.     Sisovic A., K. Sega, and N. Kalinic. Indoor/outdoor relationship of ammonia
      concentrations in selected office  buildings.  Science Total Environment. 61:73-77.
      Yugoslavia. 1987.

8.     Bracer M., P. Koutrakis, and J.D. Spengler.  Personal exposures to acidic aerosols
      and gases. Environmental Science Technology  23:  1408-1412. 1989.

9.     Lee, D.S., and GJ. Dollard.  Uncertainties  in Current Estimates of Emissions of
      Ammonia in the United Kingdom.  Environmental  Pollution, (in press in 1994).

10.    Allen, A.G., R.M. Harrison, and M.T. Wake. A Meso-Scale Study of the Behavior of
      Atmospheric Ammonia and Ammonium.  Atmospheric Environment  Volume (22),
      Number 7:1347-1353. Great Britain.  1988.

11.    Buijsman, Ed. H.F.M. Maas, and W.A.H. Asman.  Anthropogenic NH3 Emissions in
      Europe Atmospheric Environment  Volume  21, Number 5:1009-1022.  Great Britain.
      1987.
                                        6-10

-------
12.    King, L.D.  Mineralization and gaseous loss of nitrogen in soil-applied liquid sewage
       sludge.  J. envir. Qual. 2,356-358.  1973.

13.    Beauchamp, E.G.,  G.E. Kidd, and G. Thurtell.  Ammonia volatilization from sewage
       sludge applied in the field. J. envir. Qual. 7,141-146.  1978.

14.    Kruse, M., H.M. ApSimon, and J.N.B. Bell.  Validity and Uncertainty in the
       Calculation of an Emission Inventory for Ammonia Airing from Agriculture in Great
       Britain.  Environmental Pollution 56:237-257. Great Britain.   1989.

15.    Lee, D.S., P.D. Nason, and S.L. Bennett.  Atmospheric Ammonia in the Vicinity of a
       Sewage Treatment Plant - results from a preliminary investigation.  AEA-EE-0328.
       Environmental Physics Group, Environmental Safety Division, AEA Environment and
       Energy, Harwell Laboratory, Oxfordshire, England.  May 1992.

16.    Letter from Richard Bode, Manager, Special Pollutants Emission Inventory Division,
       Technical Support Division, California Air Resources Board, to Rebecca Battye, EC/R
       Incorporated.  May 16, 1994.  Transmitting data from the California Air Toxics Hot
       Spots program.

17.    J.W. Erisman. Ammonia Emissions in the Netherlands in 1987 and 1988.  National
       Institute of Public  Health and Environmental Protection.  Bilthoven, The Netherlands.
       July 1989.

18.    Lee, D.S., and J.W.S. Longhurst.  Estimates of Emissions of SO2, NO,., HCl and NH3
      from a Densely Populated Region of the UK.  Environmental Pollution, Volume 79:37-
       44.  1993.

19.    Buijsman, E.  Historical Trends in Ammonia Emission in Europe (1870-1980).  Report
       R-86-9, Institute for Meteorology and Oceanography, State University of Utrecht,  The
       Netherlands.  1986.

20.    Dawson, G.A. Atmospheric ammonia from undisturbed land.  J. geophys.  Res.
       82,3125-3133.  1977.

21.    Denmead, O.T. An Ammonia Budget for Australia.  Australian Journal of Soil
       Resources.  28:87-900. Australia.  1990.

22.    Metcalfe, S.E., D.H.F. Atkins, and R.G. Derwent.  Acid deposition modeling and
       interpretation of the United Kingdom secondary precipitation network data. Atmos.
       Environ..  23,2033-52.  1989.

23.    Schlesinger, W.H.  and A.E. Hartley.  A Global Budget for Atmospheric NH3.
       Biogeochemistry,  1992.
                                         6-11

-------
24.     Baumeister, T. (ed.). Marks' Mechanical Engineers' Handbook.  McGraw-Hill, New
       York, NY.  1958.  pg.  18-4.

25.     Chemical Economics Handbook.  SRI International, Palo Alto, California.  1989.

26.     Letter from L.B. Frank, U.S. Coast Guard, National Response Center, to Rebecca
       Battye,  EC/R Incorporated. May 3, 1994.  Transmitting computer files  of release
       reports  for ammonia.
                                         6-12

-------
                                       SECTION 7

                     CONCLUSIONS AND RECOMMENDATIONS

       A review of the literature published since 1985 has revealed new data on sources and rates
of NH3 emissions.  The majority of the literature has been published in Europe in support of acid
deposition research. The literature and the NH3 emission measurement programs in Europe have
focused on agricultural sources:  primarily, animal husbandry and fertilizer application. Recent
inventories for Europe and European nations indicate that these agricultural sources contribute up
to 80 percent of the NH3 emissions. Additional studies, relating to global climate research,
indicate that biomass burning and undisturbed soils may contribute up to half of the global NH3
emissions; however, these sources are generally excluded from the European NH3 inventory
work.

       Ammonia emission factors were developed for the National Acid Precipitation Assessment
Program (NAPAP). The NAPAP factors were compared with the available information on NH3
emissions and emission rates.  Recommendations on NH3 emission factors for future emission
inventory development work in the United States are presented. These recommendations include
the use of the European results for agricultural sources, and the use of the Compilation of Air
Pollutant Emission Factors - Volume 71 for the majority of the stationary industrial sources.
Factors for three new industrial categories have been developed.  These are beet sugar
production, froth flotation in mineral processing, and mineral wool (fiberglass) production.
Discreet industrial  sources of NH3, with no corresponding emission factors, are identified through
the Toxic Release Inventory. Additional sources of NH3 include combustion (and control
methods for NOX emissions from combustion), human breath and perspiration, publicly owned
treatment works (POTW's), and NH3 as a refrigerant.

       The following  discussion summarizes the emission factors recommended for use in future
inventories and discusses additional research that could be conducted to enhance future NH3
inventory efforts in the U.S.

7.1 RECOMMENDED EMISSION FACTORS

       Tables 7-1 through 7-5 present the recommended emission factors, classification  codes for
U.S. inventory efforts, the emission factor ratings based on the criteria presented in Appendix A,
and estimates of NH3 emissions, where available.

7.2 RELATIVE SOURCE STRENGTH IN THE U.S.

       Estimates of NH3 emissions in the U.S. are graphically illustrated in Figure 7-1. These
emission estimates are not comprehensive and are presented only to illustrate the relative
magnitude of the emissions, in order to frame the recommendations for future
                                           7-1

-------
TABLE 7-1. RECOMMENDED AMMONIA EMISSION FACTORS FOR ANIMAL HUSBANDRY
Source
(U.S. Agricultural Statistics
Classifications)
Cattle and Calves - Composite
Cows and heifers that have calved
(Beef cows)
Cows and heifers that have calved
(Milk cows)
226.8 kg (500 pounds) and over:
Heifers - Beef cow replacements
226.8 kg (500 pounds) and over:
Heifers - Milk cow replacements
226.8 kg (500 pounds) and over:
Heifers - Other
226.8 kg (500 pounds) and over:
Steers
226.8 kg (500 pounds) and over:
Bulls
Calves under 226.8 kg (500
pounds)
Hogs and Pigs - Composite
Kept for breeding
Sows farrowing
Other - kept for breeding
Market hogs by weight groups
Under 27.2 kg (60 pounds)
27.2 to 54.0 kg (60 to 119
pounds)
54.1 to 81.2 kg (120 to 179
pounds)
AMS 1991 Emission Factor Emission Factor
Classification Populations Classifications (kg NH3/animal)
Codes (106 animals) (Asman, 1992)
28-05-020-000
28-05-020-001
28-05-020-002

28-05-020-003
28-05-020-004
28-05-020-005
28-05-020-006
28-05-020-007
28-05-020-008
28-05-025-000
28-05-025-010
28-05-025-011
28-05-025-012
28-05-025-020
28-05-025-021
28-05-025-022
28-05-025-023
100
33.8
9.90

5.75
4.20
8.68
16.7
2.28
18.7
57.75
7.25
6.02
1.23

18.7
13.0
10.4

Dairy & calf cows
Dairy & calf cows

Young cattle for fattening
Young cattle
Young cattle
Fattening/grazing cattle >
2yr
Breeding bulls > 2 yr
Fattening Calves


Breeding sows > 50 kg.
Breeding sows 20-50 kg

Fattening pigs
Fattening pigs
Mature boars
22.9
39.72
39.72

15.19
13.04
13.04
8.22
27.91
5.23
9.21

16.13
5.22

6.98
6.98
11
Factor
Rating
B
B
B

B
C
B
C
C
B
B

B
C

B
C
B
Emission Factor
(Ib NH3/animal)
50.5
87.57
87.57

33.49
28.75
28.75
18.12
61.53
11.53
20.30

35.56
11.5

15.4
15.4
24.3
Estimated
emissions
(Gg/year)
2,290
1,342
393

87
55
113
137
64
98
531

97.1
6.52

131
90.7
114
                                 (Continued)

-------
TABLE 7-1. RECOMMENDED AMMONIA EMISSION FACTORS FOR ANIMAL HUSBANDRY (Continued)
Source
(U.S. Agricultural Statistics
Classifications)
81.3 to 99.3 kg and 99.4 kg (180
pounds) and over
Poultry - Chickens - Composite
Hens
Pullets - Of laying age
Pullets - 3 months old and older
not of laying age
Pullets - Under 3 months old
Other chickens
Broilers
Poultry - Other
Ducks
Turkeys
Young turkeys
Old turkey
Fryer-roasted turkey
Sheep and Lambs - Composite
Sheep and lambs on feed
Stock sheep-lambs-ewes
Stock sheep-lambs-wethers and
rams
Stock sheep- 1 yr. and over- ewes
Stock sheep- 1 yr. and over-
wethers and rams
AMS 1991 Emission Factor Emission Factor
Classification Populations Classifications (kg NH3/animal)
Codes (106 animals) (Asman, 1992)
28-05-025-024 8.4
28-05-030-000 6,497
28-05-030-001 116
28-05-030-002 162
28-05-030-003 33.5

28-05-030-004 40.8
28-05-030-005 6.85
28-05-030-006 6,138
28-05-035-000
28-05-035-001 20.0
28-05-035-002 285
28-05-035-003
28-05-035-004
28-05-035-005
28-05-040-000 10.85
28-05-040-001
28-05-040-002
28-05-040-003

28-05-040-004
28-05-040-005
Mature boars

Mother animals > 6 mo.
Laying hens > 1 8 wk.
Mother animals < 6 mo.

Laying hens < 1 8 wk.

Broilers

Ducks
Turkeys for slaughter
Turkeys < 7 mo.
Turkeys > 7 mo.
Turkeys for slaughter
Ewes
Ewes
Ewes
Ewes

Ewes
Ewes
11
.1787
0.598
0.305
0.269

0.17
0.179
0.167

0.117
0.858
0.89
1.278
0.858
3.37
3.37
3.37
3.37

3.37
3.37
Factor
Rating
B
B
B
B
C

B
C
B

B
B
B
B
C
D
D
D
D

D
D
Emission Factor
(Ib NH3/animal)
24.3

1.32
.672
.593

.375
.395
.368

.258
1.89
1.96
2.82
1.89
7.43






Estimated
emissions
(Gg/year)
92
1,161
69.4
49.4
9.01

6.94
1.23
1,025
247.3
2.34
245



36.56






                                        (Continued)

-------
TABLE 7-1. RECOMMENDED AMMONIA EMISSION FACTORS FOR ANIMAL HUSBANDRY (Continued)
Source
(U.S. Agricultural Statistics
Classifications)
Miscellaneous Farm Animals
Goats
Mink
Fox
Rabbit
Miscellaneous Domestic Animals
Cats
Dogs
Horses
AMS 1991
Classification Populations
Codes (106 animals)
28-05-045-000
28-05-045-001
28-05-045-002 3.27
28-05-045-003
28-05-045-004
27-10-020-000
27-10-020-010
27-10-020-020
27-10-020-030
Emission Factor
Classifications
(Asman, 1992)

Milch goats
Mink
Fox
Rabbit

Cats
Dogs
Horses & ponies
Emission Factor
(kg NH3/animal)

6.4
0.58
2.25
2.8

0.83
2.5
12.2
Factor
Rating

E
E
E
E

E
E
E
Emission Factor
(Ib NH3/animal)

14.1
1.28
4.96
6.2

1.83
5.5
26.9
Estimated
emissions
(Gg/year)


1.90







-------
               TABLE 7-2. RECOMMENDED AMMONIA EMISSION FACTORS FROM
                                   FERTILIZER APPLICATION
Description
Anhydrous ammonia
Aqua ammonia
Nitrogen solutions
Urea
Ammonium nitrate
Ammonium sulfate
Ammonium thiosulfate
Other straight nitrogen
Ammonium phosphates
N-P-Kb
Total
AMS code
28-01-700-001
28-01-700-002
28-01-700-003
28-01-700-004
28-01-700-005
28-01-700-006
28-01-700-007
28-01-700-008
28-01-700-009
28-01-700-010

Emission
factor
(kg NH,/Mg N)
12
12
30
182
25
97
30
30
48
48

Factor
rating
C
C
C
B
C
C
C
C
C
C

Emission
factor
(Ib NHVton N)
24
24
61
364
49
194
61
61
97
97

Estimated
annual
emissions
(Mg)
35,353
664
74,042
271,250
13,137
14,631
571
5,763
44,487
43,692
503,590
aNo factor was developed for the noted category.
bNitrogen(N)-phosphorus(P)-potassium(K) mixtures.

-------
                 TABLE 7-3. SUMMARY OF INDUSTRIAL AMMONIA EMISSION FACTORS
Source
Ammonium Nitrate Manufacture6
Neutralizer


Evaporation/concentration

Solids Formation Operations
high density prill towers
low density prill towers
rotary drum granulators
pan granulators
Coolers and dryers8
high density prill coolers
low density prill coolers
low density prill dryers
Petroleum Refineries
FCC units

TCC units (moving bed catalytic
cracking units)
Reciprocating engine compressors

Point
Source
scca

3-01-027-04
3-01-027-11
3-01-027-21
3-01-027-17
3-01-027-27

3-01-027-12
3-01-027-22
3-01-027-07
3-01-027-08

3-01-027-14
3-02-027-23
3-01-027-25

3-06-002-01

3-06-003-01

h

Emission
Factor
(kg/unit)

0.43-18.0


0.27-16.7


28.6
0.13
29.7
0.07

0.02
0.15
0-1.59

0.155

0.017

3.2

Units

Mg of product


Mg of product


Mg of product
Mg of product
Mg of product
Mg of product

Mg of product
Mg of product
Mg of product

103 liters fresh
feed
103 liters fresh
feed
103 m3 gas
burned
Emission
Factor
Ratingb

B


A


A
A
A
A

A
A
A

B

B

B

Emission
Factor
(Ib emitted/
SCC unit)c

0.86-36.0


0.54-33.4


57.2
0.26
59.4
0.14

0.04
0.30
0-3.18

54

6

0.2

1985
Emissions
(kg/yr)d

8,082
9,898
3,665
2,225
1,237

30,955
38
1,819
f

7.3
0
52.6

19,411

24

h

NH3 Synthesis
       Carbon dioxide regeneration
3-01-003-08
1.0
Mg of product
2.0
2,221
                                                 (Continued)

-------
             TABLE 7-3.  SUMMARY OF INDUSTRIAL AMMONIA EMISSION FACTORS (Continued)
Source
Condensate steam stripping
Urea Manufacture
Solution formation/concentration
Solids formation
nonfluidized bed prilling
agricultural grade*
fluidized bed prillingk
agricultural grade
feed grade
drum granulation
rotary drum cooler
Coke Manufacture"
Wet coal oven charging - Larry car
Door leaks
Coke pushing
Ammonium Phosphate Manufacture

Point
Source
scca
3-01-003-09

3-01-040-02


3-01-040-08

3-01-040-10
3-01-040-11
3-01-040-04
3-01-040-12

3-03-003-02
3-03-003-08
3-03-003-03
3-01-030°

Emission
Factor
(kg/unit)
1.1

9.231


0.43

1.46
2.071
1.07m
0.0256

0.01
0.03
0.05
0.07

Units
Mg of product

Mg of product


Mg of product

Mg of product
Mg of product
Mg of product
Mg of product

Mg coal charged
Mg coal charged
Mg coal charged
Mg P205
produced
Emission
Factor
Ratingb
E

A


A
A

A
A
A

D
D
D
E

Emission
Factor
(Ib emitted/
SCC unit)c
2.2

18.461


0.87

2.91
4.141
2.15m
0.051

0.02
0.06
0.1
0.14

1985
Emissions
(kg/yr)d
1,571

20,014


0

340
9.5
1,314
.045

162
293
618.7
259

"Refers to SCCs that were in the 1985 NAPAP Emission Inventory.

bSee Appendix A of this report for a definition of the ratings.

°A11 factors chosen are fmmAP-42.

Emissions are from the 1985 NAPAP emission inventory and totals do not include 20,057 Mg from minor point source process emissions; area source
category 99.
                                                       (Continued)

-------
              TABLE 7-3.  SUMMARY OF INDUSTRIAL AMMONIA EMISSION FACTORS (Continued)

eGiven as ranges because of variation in data and plant operations. All factors are uncontrolled, factors for controlled emissions are not presented due
to conflicting results on control efficiency.

fNH3 emissions from pan granulators were not presented by Warn et al. (1990) and were not included in the 1985 NAPAP emission inventory.

Tactors for coolers represent combined precooler and cooler emissions, and factors for dryers represent combined predryer and dryer emissions.

hNot available.

'EPA test data indicated a range of 4.01 to 14.45 kg/Mg (8.02 to 28.90 Ib/ton).

Teed grade factors were determined at an ambient temperature of 14° to 21° C (57° to 69°F).

"Teed grade factors were determined at an ambient temperature of 29 °C (85 °F) and agricultural grade factors at an ambient temperature of 27 °C
(80°F).

'For fluidized bed prilling, feed grade, there is a controlled emission factor with an A rating of 1.04 kg/Mg (2.08 Ib/ton of product) based on use of an
entrainment scrubber.

mEPA test data indicated a range of 0.955 to 1.20 kg/Mg (1.90 to 2.45 Ib/ton).

"All factors are for uncontrolled emissions.

"The emission factor is for the whole plant, all processes.

-------
              TABLE 7-4.  RECOMMENDED EMISSION FACTORS FOR COMBUSTION SOURCES
       Source
               Source Classification Codes
 Emission Factor    Factor    Emission Factor
  (metric units)	Rating     (english units)
Coal Combustion
Fuel Oil Combustion
Natural Gas
Combustion - Utility
and Industrial Boilers

Natural Gas
Combustion -
Commercial Boilers
lOlOOlxx, 101002xx, 101003xx, 10200Ixx, 102002xx,
102003xx, 103001xx, 103002xx, 103003xx, 10500102,
10500202
21-99-001-000, 21-99-002-000, 21-99-003-000

101004XX, 101005xx, 102004xx, 102005xx, 103004xx,
103005xx, 10500105, 10500205, 21-99-004-000, 21-99-005-
000

101006xx, 102006xx, 21-01-006-xxx, 21-02-006-xxx
103006xx, 21-03-006-xxx
0.00028 kg/Mg      E
0.096 kg/103 liters    E
51. kg/106 m3
7.8 kg/106 m3
C
C
SCR - Gas
101006xx, 102006xx, 103006xx, 10500106, 10500206,
201002xx, 202002xx, 203002xx
146. kg/106 m3       C
         0.565 lb/103 ton
          0.8 lb/103 gal
 3.2 lb/106 ft3
0.49 lb/106 ft3
Mobile Sources -
Leaded Gasoline*
Mobile Sources -
Diesel
SCR - Coal
SCR - Oil
22-01-xxx-xxx
22-30-xxx-xxx
10 100 Ixx, 101002xx, 101003xx, 10200 Ixx, 102002xx,
102003xx, 103001xx, 103002xx, 103003xx, 10500102,
10500202
101004xx, 101005xx, 102004xx, 102005xx, 103004xx,
103005xx, 10500105, 10500205, 201001xx, 201009xx,
202001xx, 202003xx, 20200401, 20200501, 202009xx,
203001xx, 20300301
0.050 kg/103 liter D
0.11 kg/103 liter E
0.155 kg/Mg C
0.17 kg/103 liters C
0.42 lb/103
gallons
0.95 lb/103
gallons
0.3 lib/ton
1. 4 lb/103 gallons
          9.1 Ib/MMscf
                                                       (Continued)

-------
        TABLE 7-4. RECOMMENDED EMISSION FACTORS FOR COMBUSTION SOURCES (Continued)
        Source
               Source Classification Codes
 Emission Factor
  (metric units)
Factor   Emission Factor
Rating    (english units)
 SCR - Wood

 SNCR - Coal



 SNCR - Oil



 SNCR - Gas


 SNCR - Wood
101009xx, 102009xx, 103009xx

lOlOOlxx, 101002xx, 101003xx, 10200Ixx, 102002xx,
102003xx, 103001xx, 103002xx, 103003xx, 10500102,
10500202

101004xx, 101005xx, 102004xx, 102005xx, 103004xx,
103005xx, 10500105, 10500205, 201001xx, 201009xx,
202001xx, 202003xx, 20200401, 20200501, 202009xx,
203001xx, 20300301

101006xx, 102006xx, 103006xx, 10500106, 10500206,
201002xx, 202002xx, 203002xx

101009xx, 102009xx, 103009xx
0.155 kg/Mg

0.315kg/Mg
288 kg/106 m3
0.315 kg/Mg
C          0.3 lib/ton

C          0.63 Ib/ton
0.35 kg/103 liters     C
         2.9 lb/103 gallons
C          18 Ib/MMscf
C         0.63 Ib/MMscf
"Emission factors for leaded gasoline are not presented because leaded gasoline is almost completely phased out and the source category classifications
for the U.S. do not distinguish between leaded and unleaded gasoline.

-------
         TABLE 7-5. RECOMMENDED EMISSION FACTORS FOR MISCELLANEOUS SOURCES
Classification
Code
28-10-010-000
5-01-007-01
26-30-000-000

27-01-001-000
27-01-470-000
27-01-240-000
27-01-450-000
23-02-080-002
Description
Humans
POTWs
Wastewater treatment -
Composite
Natural sources - Biogenic -
plants - forests - Composite
Natural sources - Biogenic -
plants - Tropical savannah -
Composite
Natural sources - Biogenic -
plants - Vegetation/grassland -
Composite
Natural sources - Biogenic -
plants - desert scrub - Composite
Food & Kindred Products - Misc.
- Refrigeration
Emission Factor
(kg NH3/unit)
0.25
2.2


0.1 to 1.0
0.25 to 0.75
0.01 to 1.00
0.01 to 0.25
187
Unit
person
106 liters


gNH3(N)/m2
gNH3(N)/m2
gNH3(N)/m2
gNH3(N)/m2
kg/employee
Factor
Rating
E
E


E
E
E
E
E
Emission Factor
(Ib NH3/SCC or
AMS unit)
0.55
19


Ito 10
2.7 to 8.1
0.1 to 10.
0.1 to 2.7
413
Estimated annual
emissions (Mg)
62,500a
107,000b


c
c
c
c
270,000
aBased on a U.S. population of 250 million people.
bBased on annual estimate of 12.4 x 1012 gallons treated.
°Unknown.

-------
research.  These rough estimates of U.S. NH3 emissions indicate that agricultural practices,
specifically animal husbandry and fertilizer application, dominate emissions here, just as they do in
Europe. Industrial emissions of NH3 and NH3 from combustion (excluding open or biomass
burning) are relatively insignificant. Emissions from POTW's and refrigeration may be significant,
based upon the current information gathered.  Emission factors for both of these source
categories have a rating of E, and further research into these sources is recommended. Estimates
of NH3 from biomass burning and undisturbed soils were not made, due to the unavailability of an
emission factor for biomass burning and of activity data for undisturbed soils.  Recent research
indicates that these two categories may contribute significantly (up to half) of global NH3
emissions.  Additional research into these two categories of emissions is recommended.

                                                  C a ttle and  Calves (43.4%)
   Hogs and Pigs (10.1%)
                     Poultry (26.7% )
                                                                    Industry AP-42  (0.0%)

                                                                    Refrigeration  (5.1%)


                                                                  Combustion (1.3%)
                                                                  Humans (1.2%)
                                                                P O T W s (2.0% )
       Fertilizer Application (9.5% )

Sheep  & lambs (0.7%)
  Figure 7-1. Relative contribution of ammonia emissions from different source
  categories.

       In the mid 1980's, Allen et al. (1988)2 measured ground-level concentrations of NH3 and
ammonium (NH4+) at nineteen sites within a 35-km radius of Colchester, U.K. The sampling sites
were selected to reflect the influences of different possible sources upon concentration of NH3.
The six sites included livestock farms (sheep at one site, pigs at one site, turkeys kept seasonally
at both sites, and sheep kept seasonally at a third site), landfill sites, sewage treatment works, an
arable farm, urban sites, and a marine site. Other samplers were sited at typical rural locations,
without obvious sources of specific NH3 emissions.  The livestock farms show very pronounced
elevations, and the site used  seasonally  for sheep shows a possible slight elevation.  Thus,
livestock farming appears to be confirmed as a major local influence.  Other sites show minor
variations in NH3  concentrations, but no major inter-site differences are seen. Arable farming
apparently raises arithmetic mean concentrations, but the influences of landfill operations, sewage
treatment by percolating filters, or urban activities are minor or insignificant. These data support
the conclusions in this report.

-------
       The data collected by Allen et al. (1988) show a very pronounced seasonal variation, with
the highest levels occurring in the summer and the lowest levels occurring during the winter
months.  This finding is consistent with those regarding the influence of temperature upon both
biogenic and chemical releases of NH3 from soils and fertilizers. The NH3 concentrations failed to
demonstrate any consistent diurnal patterns.  Additional investigation into both the seasonal and
diurnal pattern of emissions is recommended to support future atmospheric modeling efforts.

7.3 RECOMMENDED RESEARCH

       European researchers have conducted the majority of the research in NH3 emissions.  In
addition, several articles were uncovered in the European literature that represent new field
measurement programs whose results have not yet been incorporated into the literature.
Specifically, there is ongoing research in the United Kingdom to improve the emission factors
from humans  and from POTWs.

       Table  7-6 summarizes potential research projects that could enhance the quality of the
NH3 emissions estimates.

     TABLE 7-6. RECOMMENDED AMMONIA EMISSION FACTOR RESEARCH
                                         PROJECTS
 Source Category
                          Description of Research
 Activity data
 Animal Husbandry
In order to properly rank research programs, additional confidence on recent activity
for known sources of NH3 would result in increased knowledge of relative strength
and, consequently, the impact of various uncertainties in the emission factors. For
example, biomass burning, acreage and type of undisturbed land, and pet (including
horses) populations, should be investigated to provide increased resolution on the
emission estimates presented above.

Asman (1992)3 presents very detailed emission factors for most categories of animal
husbandry. Investigation into the primary sources of data used by Asman (1992)
would result in more confidence in the link between the European factors and the U.S.
statistics and agricultural practices and, therefore, increased accuracy in the use of the
factors for U.S. inventories.

Examination of the differences between the values used for sheep by Denmead (1990)4
for Australia and by Asman (1992) for Europe will increase the confidence in the
value recommended for use in the U.S.	

Only one research program has quantified NH3 from cats and dogs (Cass et al, 1982).5
Due to the datedness of this effort, it was not obtained and reviewed for the present
report.  It is, therefore, not known how much domestic pet populations contribute to
NH3 emissions.  Additional field level research on emissions from domestic animals
may be warranted.

                     (Continued)
                                              7-13

-------
     TABLE 7-6.  RECOMMENDED AMMONIA EMISSION FACTOR RESEARCH
                                     PROJECTS (Continued)
 Source Category
                            Description of Research
 Fertilizer             Ammonia emissions from urea fertilizer application range from 5 to 50 percent of the
 Application           applied nitrogen content. Although we are comfortable with the average emission
                      factor of 15 percent, the wide range in potential emissions can have a strong impact
                      on the overall NH3 emission inventory in a given area. There are some very
                      comprehensive models that relate NH3 emissions to various parameters, including
                      temperature, soil conditions, and application practices. These models could be used to
                      develop State-specific or crop-specific emission factors, if more information were
                      gathered on fertilizer application practices. In addition, various investigators have
                      been studying methods for reducing NH3 losses from urea.  This  may warrant future
                      downward adjustments to the urea emission factor.

                      The present study  focused on data published since 1985.  Review of European
                      inventories revealed extensive emissions from various ammonium fertilizers. In
                      general, the European emission factors for ammonium fertilizer are adopted in this
                      report without revision, because there have not been subsequent measurements. A
                      review of the pre-1985 measurements used in the European studies may give factors
                      that are somewhat different.

 Nonagricultural       There is huge variability (four orders of magnitude) in the emission factors used to
 Soils                 develop the composite factors presented. Additional effort could be expended on
                      analyzing the primary data sources to gain confidence in the composite factors
                      developed. In addition, the emission factors should be linked to  the land use land
                      cover categories recently developed to support biogenic emission estimation models.

 Refrigeration         The emission factor presented is a per employee factor based on the amount of NH3
                      used in this application.  The data on the quantity of NH3 used should be verified, due
                      to its large contribution.  The method used to allocate these emissions (employment
                      statistics) may be inconsistent with the way in which these emissions occur. As freon
                      is phased out, the emissions from refrigeration may change.

 POTW's              The article on Atmospheric Ammonia in the Vicinity of a Sewage Treatment Plant -
                      results from  a preliminary investigation. (Lee et al, 1992)6 indicates that further work
                      is currently being undertaken to clarify the precise sources of NH3 and their
                      contribution to atmospheric budgets. This research is believed to be on-going in the
                      United Kingdom by D.S. Lee, P.D. Nason, and S.L. Bennett.

	Research is also ongoing in California to improve emission estimates from POTWs.
 Industrial Sources
Analysis of ambient air quality data collected in Louisiana and Alaska may provide
increased accuracy in emission factors for those sources (fertilizer manufacturing
sources).
                                            (Continued)

                                                7-14

-------
     TABLE 7-6. RECOMMENDED AMMONIA EMISSION FACTOR RESEARCH
                                     PROJECTS (Continued)
 Source Category
                            Description of Research
                       Further analysis of the TRIS data as indicators of potential industrial NH3 sources,
                       and the extrapolation of that data, with the NAPAP inventory and information
                       collected through MACT surveys, may provide additional information on the types,
                       locations, and numbers of industrial processes that may warrant emission factor
                       development.
 Combustion
 Human Breath &
 Perspiration
 Spills - Accidental
 Releases
An examination of the factors and research used to estimate NH3 from biomass
burning, and the search for the most appropriate source of activity data is
recommended. Biomass burning includes naturally occurring fires and may also
include prescribed agricultural burning, as well as miscellaneous structural fires. In
addition, the chemical agents that are used to fight large naturally occurring fires
should be investigated to determine if they contribute significantly to the overall NH3
emissions from fire.

Additional analysis of the NH3 emission rates from SCR and SNCR NOX control units,
as measurement data become available for new installations, should be conducted.

A test program to measure the NH3 emissions from the newer automobiles, including
natural gas fired vehicles and new catalysts, should be initiated. The data used to
support the emission factors in this report are from older automobiles (1960's and
1970's) that do not represent the current fleet.

A test program to reexamine the emission factors for fuel oil and natural gas
combustion should be initiated. NAPAP was the only inventory to include NH3
emissions from fuel oil and natural gas. The existing data indicate that fuel oil and
natural gas contribute more NH3 emissions than coal combustion, but all of the
research and data are dated.

The article on Uncertainties in Current Estimates of Emissions of Ammonia in the
United Kingdom (Lee & Bollard, 1994)7 indicates that further research on indoor NH3
concentrations at a variety of locations is currently being undertaken and will be
published in the near future. The research is believed to be on-going in the United
Kingdom by D.S. Lee and D.H.F. Atkins.

Software has been developed for extrapolating data from the Coast Guard spill data
base.  This could be extended to produce county-level results. The majority of the
NH3 reported as spills is believed to be a result of refrigeration leaks and, therefore,
factors for spills were not developed (otherwise it would result in double counting).
The assumption that NH3 emissions in this category are contributed primarily from
refrigerant leaks should be verified.	
        Five research areas are recommended to enhance the quality of NH3 emission factors
presented in this report.  The five research areas are:
        Investigate the recent global climate literature on NH3 from undisturbed soils. Merge the
        literature on emission fluxes with new land use land cover data categories to develop
        emission factors for the biogenic plants- area and mobile source classification category.

-------
Investigate recent literature on NH3 emissions from biomass burning.  Integrate the data
results with information in the U.S. on naturally occurring fires to develop emission
factors for the U.S.  Also, investigate any information on NH3 emissions from the chemical
agents used to fight these naturally occurring fires.
Research the primary references for the animal husbandry emission factors, in order to
provide more accurate linkages with the U.S. Department of Agriculture statistics.  In
addition, investigate the discrepancy in the emission factors for sheep presented by Asman
(1992) and Denmead (1990).
Develop temporal profiles for the larger NH3 emissions categories.  Specifically,
investigate the seasonal nature of the animal husbandry and fertilizer application emissions.
Confidence in the emission factors reported for the industrial categories of refrigeration,
POTWs, and selective catalytic and non-catalytic reduction (for control of NOX
emissions), may be improved with additional research. Refrigeration contributes a
significant portion of the NH3 inventory (about 5%); however, this factor was developed
based on a  material  balance. POTWs also contribute a significant amount of NH3 (about
2%); however, additional research is ongoing in the United Kingdom and California that
may improve the accuracy of this emission factor.
                                    7-16

-------
                           REFERENCES FOR SECTION 7

1.      U.S. Environmental Protection Agency. Compilation of Air Pollutant Emission Factors -
       Volume I: Stationary Point and Area Sources.  AP-42 (GPO 055-000-00251-7). Fifth
       Edition.  U. S. Environmental Protection Agency, Research Triangle Park, North
       Carolina.  July 1994.

2.      Allen, A.G., R.M. Harrison, and M.T. Wake. A Meso-Scale Study of the behavior of
       Atmospheric Ammonia and Ammonium. Atmospheric Environment  Volume (22),
       Number 7:1347-1353. Great Britain. 1988.

3.      Asman, Willem A.H.  Ammonia Emissions in Europe: Updated Emission and Emission
       Variations. National Institute of Public Health and Environmental Protection. Bilthoven,
       The Netherlands.  May 1992.

4.      Denmead, O.T. An Ammonia Budget for Australia.  Australian Journal of Soil Resources.
       28:87-900. Australia.  1990.

5.      Cass, G.R., S. Gharib, M. Peterson, and J.W. Tilden.  The origin of ammonia emissions to
       the atmosphere in an urban area.  Open File Report 82-6. Environmental Quality
       Laboratory.  California Institute of Technology.  1982.

6.      Lee, D.S., P.D. Nason, and S.L. Bennett.  Atmospheric Ammonia in  the Vicinity of a
       Sewage Treatment Plant - results from a preliminary investigation.  AEA-EE-0328.
       Environmental Physics Group, Environmental Safety Division, AEA Environment and
       Energy, Harwell Laboratory, Oxfordshire, England. May 1992.

7.      Lee, D.S., and GJ. Bollard. Uncertainties in Current Estimates of Emissions of
       Ammonia in the United Kingdom.  Environmental Pollution,  (in press in 1994).
                                         7-17

-------
                                     APPENDIX A

                 CRITERIA FOR ASSESSING EMISSION FACTORS1

       This appendix describes the criteria that were used to assess the quality of the NH3
emission factors presented in this report.  The purpose of the ratings is to provide a qualitative
indication of the reliability of the emission factors. Criteria used to assess the emission factors are
listed below.

A.1  DISCUSSION OF CRITERIA

Emission Factor Development Methods: Most emission factors are determined from either
source tests, industry surveys, mass balances, or engineering estimates. The accuracy of these
methods depends on several different parameters which change from one emission source to
another.

  !     Source Tests: In source testing, samples are taken directly from the source emitting the
       pollutant. Accurate approved test methods should have been used whenever possible. If
       an unapproved method or an  outdated method was used, the quality of the emission factor
       should be questioned.

  !     Industry Survey: In a survey, EPA submits a series of questions to a plant or site that is
       emitting the pollutant in question. The plant or site personnel voluntarily fill out and
       return the questionnaire to the surveyor. To obtain accurate information, the questions
       must be worded carefully so that the correct and desired information will be given. If
       consistent results are reported by the participants, the information may be considered
       accurate. To effectively assess the quality of an emission factor, the survey methodology
       should be known.

  !     Engineering Estimate: An engineering estimate is based on process information
       available to the engineer.  The engineer makes several assumptions and other available
       information, he estimates an emission factor.  This method of determining an emission
       factor is generally the most inaccurate.  However, with adequate background information,
       an accurate estimate can frequently be made.

Size of Database: The emission factor becomes increasingly accurate as the database from which
the factor was determined expands. Emission factors constructed on information from one source
have less credibility than those from several sources.

Database Represents a Good  Cross Section of Industry:  An average emission factor should be
determined from a cross section of the industry.  A good cross section is related to the size of the
database.  However, a large database does not ensure a good cross section, and an excellent cross
section is possible from a small database.
                                          A-l

-------
Age of Data:  Some emission factors quickly lose credibility for the following reasons:

  !     The sampling and testing methods may have been proven invalid, and as better methods
       are developed, inherent flaws in previously used methods are discovered.

  !     Technological innovations occur in most industries on a regular basis. Consequently, the
       process parameters used when the emission tests were performed may differ significantly
       from those currently used in the industry. Control systems may be more efficient, fuel
       feed and production rates may differ, the composition of pollutants may be significantly
       different, etc.  As a result, the old emission factor may no longer apply.

  !     New laws and regulations may be passed which would significantly affect the emissions
       from a source.

A.2 RATING SYSTEM

       A rating system, analogous to theAP-42 system, was developed to grade each emission
factor. Due to the variability in the type of information in the reference used to assign emission
factors, a good deal of subjective engineering judgement was used in giving each factor a grade.

       Emission factors for each process were given a rating of A through E, with the A rating
representing the more reliable emission factor and the E rating a less reliable rating.

       A qualitative description of each rating is listed below:

       A Rating

  !     Large database from surveys or source tests on several different studies was used.

  !     Database covers a cross section of the industry.

  !     Emission factors were determined by mass balance based on sound measurement.

       B Rating

  !     Database is fairly large; however, it is not clear that it represents a good cross section of
       the industry.

  !     Emission factor was measured using valid test methods at the time the test was performed.
       However, tests have since been revised.

  !     Engineering estimate based on sound, accurate information.
                                           A-2

-------
       C Rating

  !     Database consists of a few good sources.

  !     Data may or may not be representative of the industry.

  !     Engineering estimates based on accurate information. However, information is not
       extensive or complete.

       D Rating

  !     Database is small. If one sample, it was a representative site.

  !     Database may not be representative of industry.

  !     Unapproved test methods may have been used.

  !     Engineering estimates are based on information where accuracy is questionable.

       E Rating

  !     Database is small. Results conflict with each other.

  !     Any sources tested are not representative of the industry.

  !     Engineering estimates are based on very little reliable information.

       The above ratings are referred to throughout this report in the discussion of specific
emission factors.
                                           A-3

-------
                         REFERENCE FOR APPENDIX A
1.     Warn, T.E., S. Zelmanowitz, and M. Saeger. Development and Selection of Ammonia
      Emission Factors for the 1985 NAPAP Emissions Inventory.  EP A-600/7-90-014, U. S.
      Environmental Protection Agency, Research Triangle Park, North Carolina. June 1990.
                                       A-4

-------