Particulate emissions, source control

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. 

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. 

Boubel, R. W., "Control of Particulate Emissions from Wood-Fired Boilers," Stationary Source Enforcement Series, EPA 340/1-77-026. U.S. Environmental Protection Agency, Washington, DC, 1977. 

Replace old boilers - Older refinery boilers can be a significant source of SO, NO, and particulate emissions. It is possible to replace a large number of old boilers with a single new cogeneration plant with emissions controls. 

EPA, 1982. U.S. EPA, Office of Air Quality Planning and Standards, "Control Techniques for Particulate Emissions from Stationary Sources, Volume 1," EPA-450/3-81-005a, Research Triangle Park, NC, September, 1982. 

The first essential step in the design of a fume control system and selection of gas-cleaning equipment is the characterization of the fume emission source. Design procedures which can be used for new and existing industrial plants follow. The characterization of fume emission sources includes parameters such as plume flow rates (mVs), plume geometry (m), source heat flux (J/s), physical and chemical characteristics of particulates, fume loadings (mg/m ), etc. 

Figure 17-46 shows such a performance curve for the collection of coal fly ash by a pilot-plant venturi scrubber (Raben "Use of Scrubbers for Control of Emissions from Power Boilers, United States-U.S.S.R. Symposium on Control of Fine-Particulate Emissions from Industrial Sources, San Francisco, 1974). The scatter in the data reflects not merely experimental errors but actual variations in the particle-size characteristics of the dust. Because the characteristics of an industrial dust vary with time, the scrubber performance curve necessarily must represent an average material, and the scatter in the data is frequently greater than is shown in Fig. 17-46. For best definition, the curve should cover as wide a range of contacting power as possible. Obtaining the data thus requires pilot-plant equipment with the flexibility to operate over a wide range of conditions. Because scrubber performance is not greatly affected by the size of the unit, it is feasible to conduct the tests with a unit handling no more than 170 m3/h (100 ftVmin) of gas.

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). 

Heavy Metals and Folvnuclear Aromatics fPNA). Zinc emissions are frequently mentioned as an element that could increase significantly when burning TDF, because of the zinc content of the rubber. Because zinc oxide has a small particle size, sources controlled by scrubbers have particular concern that the zinc oxide will escape the control device. ESP s, on the other hand, would be well suited to pick up a small metallic particulate. Zinc was measured at all six plants evaluated here. Data on zinc emissions show that in all five data sets where comparison to baseline levels was available, zinc emission rates did increase,often dramatically. Figure 5-7 graphs zinc... 

Diesel engines, which are used in the larger vehicles, are important sources of particles and NOx, but emit relatively low amounts of CO and HCs. Diesel particulate emissions can, over time, be controlled. The control of NOx is problematic, and an appropriate technology is not available. Lean NOx catalysts are being pursued but conversion efficiencies remain low. 

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