Pollution sources particulate emissions

E. Bakke, "The AppHcation of Wet Electrostatic Precipitators for Control of Eiue Particulate Matter," Preprint, Symposium on Control of Tine Particulate Emissions from Industrial Sources, Joint U.S.-USSR Working Group, Stationay Source Air Pollution ControlTechnology, San Francisco, Calif, Jan. 15—18, 1974. 

Human-made sources cover a wide spectrum of chemical and physical activities and are the major contributors to urban air pollution. Air pollutants in the United States pour out from over 10 million vehicles, the refuse of over 250 million people, the generation of billions of kilowatts of electricity, and the production of innumerable products demanded by eveiyday living. Hundreds of millions of tons of air pollutants are generated annu ly in the United States alone. The five main classes of pollutants are particulates, sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. Total emissions in the United States are summarized by source categoiy for the year 1993 in Table 25-10. 

Particulates Procedures for testing a particulate source are more detailed than those used for sampling gases. Because particulates exhibit inertial effects and are not uniformly distributed within a stack, sampling to obtain a representative sample is more complex than for gaseous pollutants. EPA Method 5 (as shown in Fig. 25-32) is the most widely used procedure for determination of particulate emissions from a stationary source. In-stack samphng guidehnes are presented in EPA Method 17. 

To develop an emission inventory for an area, one must (1) list the types of sources for the area, such as cupolas, automobiles, and home fireplaces (2) determine the type of air pollutant emission from each of the listed sources, such as particulates and SO2 (3) examine the literature (9) to find valid emission factors for each of the pollutants of concern (e.g., "particulate emissions for open burning of tree limbs and brush are 10 kg per ton of residue consumed") (4) through an actual count, or by means of some estimating technique, determine the number and size of specific sources in the area (the number of steelmaking furnaces can be counted, but the number of home fireplaces will probably have to be estimated) and (5) multiply the appropriate numbers from (3) and (4) to obtain the total emissions and then sum the similar emissions to obtain the total for the area. 

In addition to chemicals covered under TRI, many other chemicals are released. For example, the EPA Office of Air Quality Planning and Standards has compiled air pollutant emission factors for determining the total air emissions of priority pollutants (e.g., VOCs, SO, NO, CO, particulates, etc.) from many refinery sources. The EPA Office of Aerometric Information Retrieval System (AIRS) contains a wide range of information related to stationary sources of air pollution, including the emissions of a number of air pollutants which may be of concern within a particular industry. With the exception of volatile organic compounds (VOCs), there is little overlap with the TRI chemicals reported above. 

The process of coke making emits particulate matters, volatile organic compounds (VOCs), carbon monoxide, and other pollutants. The various sources of emissions include the following ... 

Power boilers at pulp and paper mills are sources of particulate emissions, S02, and NOx. Pollutants emitted from chemical recovery boilers include S02 and total reduced sulfur compounds (TRS). 

Daisey, J. M., J. L. Cheney, and P. J. Lioy, Profiles of Organic Particulate Emissions from Air Pollution Sources Status and Needs for Receptor Source Apportionment Modeling, J. Air Pollut. Control Assoc., 36, 17-33 (1986b). 

The emphasis in the present work is on leachates derived from fly ash disposal, but it must not be forgotten that fine ash particles may escape from power plants. The transport and dispersion of particulate emissions from tall stacks has been actively researched over the last 20-30 years. A review by Carras (1995) records that plumes have been observed to remain as coherent units up to distances of at least 1800 km and thus deposit pollution far from source. However, maximum particulate surface loadings are likely to be found adjacent to old power plants with limited fine-particle fly ash entrapment. Evans et al. (1980) estimated that in a period of 23 years the cumulative stack ash load at a distance of 1.7 km from an 83 MW... 

Abstract Gaseous and particulate emissions from vehicles represent a major source of atmospheric pollution in cities. Recent research shows evidence of, along with the primary emissions from motor exhaust, important contributions from secondary (due to traffic-related organic/inorganic gaseous precursors) and primary particles due to wear and resuspension processes. Besides new and more effective (for NO emissions) technologies, non-technological measures from local authorities are needed to improve urban air quality in Europe. 

Fig. 9-22 a and b). They can be found in the immediate vicinity of the emission source. In a small area (see Tab. 9-10) the concentrations of cadmium exceed the index value of the category B of the Dutch hst [1988] (Tab. 9-11) which implies a need for more detailed investigation. By means of the kriging estimation the critical polluted area can be well assessed. The locations of the concentration maxima enable conclusions to be drawn about the source of emission. The blast furnace works in the north of the Maxhiitte proves to be the main source of iron and cadmium. This also corresponds to the impact of particulate emissions in the territory investigated (see also Fig. 9-19). 

It is our estimate that all pollutant sources result in about 300 X 10 tons per year of particulate material being introduced into the atmosphere and that pollutant and natural sources combined amount to about 3000 X 10 tons per year. Thus, on a global scale 30 X 10 tons per year of pollutant photochemical aerosols are about 10% of the total pollutant aerosols and about 1% of the total annual atmospheric aerosol production. The 200 X 10 tons of aerosol particles resulting from the photochemical scavenging reactions involving natural organic emissions is somewhat less than 10% of the total aerosols emitted to the global atmosphere. 

Power plants and refineries are the primary fixed sources of pollutant emissions in most urban areas. However, other industrial sources, distributed throughout the area, also emit substantial amounts of contaminants. Also during the winter months effluents from home heating can add significantly to the pollutant load in the atmosphere. Sulfur dioxide and particulates are emitted from nearly all fixed sources although many of the particulate emissions are controlled by the use of abatement devices and sulfur dioxide by the use of low sulfur fuels. Also, power plants emit large amounts of nitrogen oxides, and refineries, hydrocarbons. 

The current professional ventilation standard (ASHRAE 62-89) suggests two approaches to ventilation a ventilation rate procedure and an air quality procedure. The former provides a tabular approach to ventilation requirements office buildings require 20 ft of outside air per occupant per minute to maintain occupant complaint rates of environmental discomfort at below 20%. This assumes relatively weak pollution sources. When stronger sources are present, the same rate will provide less satisfaction. For example, when smoking is permitted at usual rates (according to data from the early 1980s), 30% of occupants will complain of environmental discomfort. The second approach requires the selection of a target concentration in air (e.g., particulates, VOCs, and formaldehyde), information on emission rates (pollutant per time per mass or surface), and... 

Fluorides emitted into the atmosphere from different sources include both gaseous and particulate forms. Historically, most of the F pollution problems occurred as a result of emissions from anthropogenic sources. Such emissions occasionally resulted in the presence of harmful levels of F compounds in the environment as well as in body tissues. The forms of F emitted from these sources include hydrogen fluoride, cryolite, fluorspar, and silicon tetrafluo-ride (SiF4). The anthropogenic sources also contribute F to surface waters. 

Concentration of particles in the air as well as particle size distributions can be considered either in terms of particle number or mass. In terms of number, the vast majority of airborne particles are in the ultrafine range. For example, in urban outdoor air where motor vehicle emissions are a dominant pollution source, over 80% of particulate matter in terms of number is in the ultrafine range [17]. Since outdoor particles contribute significantly to indoor particle concentrations, also in indoor air particle number concentration is usually dominated by the smallest particles. However, most of the mass of airborne particles is associated with large particles since the mass of ultrafine particles is often very small in comparison with the mass of larger particles. The particle surface area in turn is largest for particles somewhat above the ultrafine size range. 

Pollutants are emitted daily with the effluents produced by stationary and non-stationary sources. The first type includes industrial processes, energy production, waste incineration, and domestic burning, whereas the second type includes automotive emissions and emissions from aeroplanes. Road and air traffic make a substantial contribution to NO and particulate emissions. 

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