Pollutants particulate

Scrubbers. Scrubbers are designed to contact a liquid with the particle-laden gas and entrain the particles with the liquid. They offer the obvious advantage that they can be used to remove gaseous as well as particulate pollutants. The gas stream may need to be cooled before entering the scrubber. Some of the more common types of scrubbers are shown in Fig. 11.2. 

Gaseous and particulate pollutants are withdrawn isoldnetically from an emission source and collected in a multicomponent sampling train. Principal components of the train include a high-efficiency glass- or quartz-fiber filter and a packed bed of porous polymeric adsorbent resin (typically XAD-2 or polyurethane foam for PCBs). The filter is used to collect organic-laden particulate materials and the porous polymeric resin to adsorb semivolatile organic species (com-... 

The three major characteristics of particulate pollutants in the ambient atmosphere are total mass concentration, size distribution, and chemical composition. In the United States, the PM q concentration, particulate matter with an aerodynamic diameter <10 /nm, is the quantity measured for an air quality standard to protect human health from effects caused by inhalation of suspended particulate matter. As shown in Chapter 7, the size distribution of particulate pollutants is very important in understanding... 

The chemical composition of particulate pollutants is determined in two forms specific elements, or specific compounds or ions. Knowledge of their chemical composition is useful in determining the sources of airborne particles and in understanding the fate of particles in the atmosphere. Elemental analysis yields results in terms of the individual elements present in a sample such as a given quantity of sulfur, S. From elemental analysis techniques we do not obtain direct information about the chemical form of S in a sample such as sulfate (SO/ ) or sulfide. Two nondestructive techniques used for direct elemental analysis of particulate samples are X-ray fluorescence spectroscopy (XRF) and neutron activation analysis (NAA). 

Fig. 15-1. CaUfomia South Coast Air Basin stationary monitoring locations operating during 1991. (L.A., Los Angeles). Source California Air Resources Board, "Summary of 1991 Air Quality Data, Gaseous and Particulate Pollutants," Vol. 23, 1991.

CaUfomia Air Resources Board, "Summary of 1991 Air Quality Data, Gaseous and Particulate Pollutants." CaUfomia Air Resources Board, Sacramento, 1991. 

PEM (Pollution Episodic Model) is an urban scale air pollution model capable of predicting short-term average surface concentrations and deposition fluxes of two gaseous or particulate pollutants. 

It has been found that particulate pollution, while causing soiling of materials, may also be responsible for increasing corrosion levels (compared to the corrosion that would be caused by the same level of acid impingement alone) by a process of adsorption. Also, particulates can react synergistically with the acid deposition to cause much greater damage. 

The Conioses Organotypic Inflammatory Oxidative Besponses to Environmental Particulate Pollutants... 

Vandegrift, A.E., Shannon, L.J. Particulate Pollutant System Study. voL II, Handbook of Emission Properties, NHS, National Technical Information Service, Commerce Department PB 203522, Springfield, Va., 197 1. 

Particulate Pollutants. Smoke, ash, viruses, pollen, sand, and in contemporary industrial society also coal and cement dust, are generally known as particulate pollutants (they occur as extremely small solid particles suspended in the atmosphere). The combination of air, pollutant gases, small liquid droplets, and particulate matter constitutes what is known as smog, which, since the second half of the eighteenth century, has beset antiquities, damaging and disintegrating even those made of stone and metals. 

Asthma rates in children in Southern California are high and oxidant pollution levels are likewise high. It is important to determine the relationship between the two. It is also important to determine whether there are chronic pulmonary effects produced by either these oxidants and/or particulate pollution. Since children spend more time outdoors than adults and since they exercise more while outdoors, the added assault from increased ventilation may be of importance. The studies feature a comprehensive exposure assessment that has led to a better understanding of the relationship between exposure and effects. It is also important to identify sub-populations of children and adults who are more susceptible to air pollution-related respiratory effects if they exist. Altered susceptibility could be based on genetic or non-genetic mechanisms (nutritional status for example). Both the epidemiologic and chamber studies provide opportunities to examine issues of hypersusceptibility and to determine the reasons for it if it exists. 

Gartrell, G., Jr., and S. K. Friedlander. Relating particulate pollution to sources The 1972 California aerosol characterization study. Atmos. Environ. 9 279-299, 1975. 

Gordon, R. J. Patterns in airborne particulate pollutants at several Los Angeles locations. Abstract ENVT 041. In Abstracts of Papers. 167th National Meeting. American Chemical Society, Los Angeles, California, March 31-April S. 1974. 

A number of components of ambient oxidant mixtures are discussed in Chapter 3. Further detailed characterization studies of ambient particulate pollution may suggest that some of these compounds are present in the organic fraction in quantities likely to be detrimental to human health. If so, further controlled health-effects studies would be indicated and might be accomplished with irradiated and diluted automobile exhaust or exposure to pure specific compounds. 

Emission inventories are often used to develop control strategies for particulate pollution, but there are difficulties... 

While such calculations can be carried out in principle, they are in fact rarely possible in the detail needed for developing reliable air quality/emission source relationships for particulate pollution. Dispersion modeling however, is necessary to predict the air quality effects of a new source which is to be located in a region where air quality/emission source relationships are poorly understood. 

Gartrell, G. and Friedlander, S. K. (1975). "Relating Particulate Pollution to Sources The 1972 Aerosol Characterization Study," Atmospheric Environment, , 279. 

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