The ''AP 42 Compilation of Air Pollutant Emission Factors'' is a compilation of the

US Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it be ...

(EPA)'s

emission factor An emission intensity (also carbon intensity or C.I.) is the emission rate of a given pollutant relative to the intensity of a specific activity, or an industrial production process; for example grams of carbon dioxide released per megajoule ...

information on

air pollution Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different type ...

, first published in 1968. , the last edition is the 5th from 2010.

History

The AP 42 Compilation of Air Pollutant Emission Factors is a compilation of

s of

air pollutants Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types ...

, in other words numbers which relate the quantity of a pollutant released into the ambient air with a certain activity. This compilation was first compiled and published by the US Public Health Service in 1968. In 1972, it was revised and issued as the second edition by the

EPA. In 1985, the subsequent fourth edition was split into two volumes: Volume I has since included stationary point and area source

s, and Volume II includes mobile source emission factors. Volume I is currently in its fifth edition and is available on the Internet. Volume II is no longer maintained as such, but roadway air dispersion models for estimating emissions from onroad vehicles and from

non-road vehicle Non-road engines are engines that are used for other purposes than a motor vehicle that is used on a public roadway. The term is commonly used by Regulatory agency, regulators to classify the engines in order to control their Air pollution, emi ...

s and mobile equipment are available on the Internet. In routine common usage, Volume I of the emission factor compilation is very often referred to as simply ''AP 42''.

Content

Air pollution emission factors are usually expressed as the weight of the pollutant divided by a unit weight, volume, distance, or duration of the activity emitting the pollutant (e.g., kilograms of particulate matter emitted per megagram of coal burned). The factors help to estimate emissions from various sources of air pollution. In most cases, the factors are simply averages of all available data of acceptable quality, and are generally assumed to be representative of long-term averages. The equation for the estimation of emissions before emission reduction controls are applied is: :E = A × EF and for emissions after reduction controls are applied: :E = A × EF × (1-ER/100) Emission factors are used by atmospheric dispersion modelers and others to determine the amount of air pollutants being emitted from sources within industrial facilities.

Chapters

Chapter 5, Section 5.1 "Petroleum Refining" discusses the air pollutant emissions from the equipment in the various refinery processing units as well as from the auxiliary steam-generating boilers, furnaces and engines, and Table 5.1.1 includes the pertinent emission factors. Table 5.1.2 includes the emission factors for the fugitive air pollutant emissions from the large wet

cooling tower A cooling tower is a device that rejects waste heat to the atmosphere through the cooling of a coolant stream, usually a water stream to a lower temperature. Cooling towers may either use the evaporation of water to remove process heat an ...

s in

refineries A refinery is a production facility composed of a group of chemical engineering unit processes and unit operations refining certain materials or converting raw material into products of value. Types of refineries Different types of refinerie ...

and from the oil/water separators used in treating refinery

wastewater Wastewater is water generated after the use of freshwater, raw water, drinking water or saline water in a variety of deliberate applications or processes. Another definition of wastewater is "Used water from any combination of domestic, industrial ...

. The fugitive air pollutant emission factors from

relief valves A relief valve or pressure relief valve (PRV) is a type of safety valve used to control or limit the pressure in a system; pressure might otherwise build up and create a process upset, instrument or equipment failure, or fire. The pressure is ...

, piping

valves A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fitting ...

, open-ended piping lines or drains, piping

flange A flange is a protruded ridge, lip or rim (wheel), rim, either external or internal, that serves to increase shear strength, strength (as the flange of an iron beam (structure), beam such as an I-beam or a T-beam); for easy attachment/transfer of ...

s, sample connections, and

seals Seals may refer to: * Pinniped, a diverse group of semi-aquatic marine mammals, many of which are commonly called seals, particularly: ** Earless seal, or "true seal" ** Fur seal * Seal (emblem), a device to impress an emblem, used as a means of a ...

pump A pump is a device that moves fluids (liquids or gases), or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups according to the method they ...

and

compressor A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor. Compressors are similar to pumps: both increase the pressure on a fluid and both can tr ...

shafts are discussed and included the report EPA-458/R-95-017, "Protocol for Equipment Leak Emission Estimates" which is included in the Chapter 5 section of AP 42. That report includes the emission factors developed by the EPA for petroleum refineries and for the synthetic organic chemical industry (SOCMI). In most cases, the emission factors in Chapter 5 are included for both ''uncontrolled'' conditions before emission reduction controls are implemented and ''controlled'' conditions after specified emission reduction methods are implemented. Chapter 7 "Liquid Storage Tanks" is devoted to the methodology for calculating the emissions losses from the six basic tank designs used for organic liquid storage: fixed roof (vertical and horizontal), external floating roof, domed external (or covered) floating roof, internal floating roof, variable vapor space, and pressure (low and high). The methodology in Chapter 7 was developed by the

American Petroleum Institute The American Petroleum Institute (API) is the largest U.S. trade association for the oil and natural gas industry. It claims to represent nearly 600 corporations involved in production, refinement, distribution, and many other aspects of the ...

in collaboration with the EPA. The EPA has developed a software program named "TANKS" which performs the Chapter 7 methodology for calculating emission losses from storage tanks. The program's installer file along with a user manual, and the source code are available on the Internet.TANKS download site
Chapters 5 and 7 discussed above are illustrative of the type of information contained in the other chapters of AP 42. Many of the

fugitive emission Fugitive emissions are leaks and other irregular releases of gases or vapors from a pressurized containment – such as appliances, storage tanks, pipelines, wells, or other pieces of equipment – mostly from industrial activities. In addition ...

factors in Chapter 5 and the emissions calculation methodology in Chapter 7 and the TANKS program also apply to many other industrial categories besides the petroleum industry.

Other sources of emission factors

The Global Atmospheric Pollution (GAP) Forum Air Pollutant Emissions Inventory Manual
Stockholm Environment Institute, Version 1.7, October 2010 sei-international.org.
United Kingdom's emission factor database
archived 201
National Atmospheric Emissions Inventory
UK

EMEP/European Environment Agency 2007 Guidebook, was updated 2016
IPCC Emission factors Database
2006

Revised 1996 .
Fugitive emissions leaks from ethylene and other chemical plants
harc.edu 2002.

Australian National Pollutant Inventory, 2006.
Canadian Greenhouse Gas Inventory Methodologies
National Air Pollution Surveillance Program, (Canada) 2018-05-29, retrieved 2018-07-13
Sangea - Greenhouse Gas Emission Estimation Software
American Petroleum Institute, 2012 by Trinity Consultants/T3.

Mining Association Of Canada, 2000, The Pembina Institute, and Stratos Inc.
Air Pollutant Emission Factor Library
Finnish Environment Institute, retrieved 2018-07-13. (includes info from EMEP/EEA Guidebook of 2016)

References

{{DEFAULTSORT:Ap 42 Compilation Of Air Pollutant Emission Factors Smog Air pollution emissions Air pollution in the United States Atmospheric dispersion modeling United States Environmental Protection Agency 1968 in the environment

History

Content

Chapters

Other sources of emission factors

See also

References