Collection from coal-fired power plants

See also Acid precipitation Acidic gases, collection from coal-fired power plants, 84-91 Acridine, nitrogen contents, 305 Acridine char... 

M. E. Kitto and D. L. Anderson, "Simultaneous collection of particles and acidic gases for tracing emissions from coal-fired power plants," presented at the Amer. Chem. Soc. National Meeting, New York, April, 1986. 

Simultaneous Collection of Particles and Acidic Gases for Tracing Emissions from Coal-Fired Power Plants... 

Coal-Fired Power Plants. Detailed studies of compositions of particles collected from stacks of about ten coal-fired power plants have been performed (, 27-36). In a few cases, the composition has been determined for particles In several size groups. Some measurements on suspended particles have been aug-... 

A series of mercury mass balances was obtained at a coal-fired power plant by comparing the volatile and particulate mercury in the stack gas stream to the mercury initially in the coal, corrected for the mercury adsorbed and retained by the various ashes. These data were used to determine the fate of the mercury in the combustion process and to check the accuracy of the volatile mercury sampling procedure (gold amalgamation). The bottom ash had the lowest mercury concentration of the ash samples collected, and the mercury concentration increased as one proceeded through the ash collection system from the initial mechanical ash to the electrostatic ash. The mercury recovered in the various ashes represented about 10% of the total mercury introduced in the raw coal. 

The characteristics of several QCM instruments for aerosol measurement have been reviewed (ll). Particles are collected by impaction, electrostatic precipitation or both. The mass sensitivity is reported to be affected by the location of deposited particles on the crystal, the size of the particles, and the type of coating. In addition, the sensitivity changes as the crystal becomes loaded. Despite some limitations, most of the studies Indicated that QCMs can be successfully used for aerosol measurement with good correlation coefficient with the reference filtration method. Applications included measurement of aerosol in ambient air, particulate emission from automobiles and diesel engines, smoke plume from a coal-fired power plant, solid fueled rocket plvune, and particulate matter in the effluents in combustion sources. 

Passive biomonitoring was applied to estimate the air quality in the La Spezia district, Italy, with regard to a coal-fired power plant and other industrial activities (Nimis et al., 1990). The lichen Parmelia caperata collected from Olea sativa trees was meant to biomonitor the SO2 pollution in the study area. The method, adopted by Nimis et al., was designed to avoid subjectivity, to begin with the strategy of sampling and end with the analysis of data. The applied index, based on frequency of species... 

Tuncel et al. tabulated S/Se ratios for particles from many locations (4). The ratio is about 3000 at rural sites downwind, but outside of coal-burning areas. In the midst of the ORV, it is depressed to about 1700, in agreement with the model. In the midst of cities in which substantial coal is burned, the ratio is depressed to 1000 or less. Except for a few samples at Allegheny Mt. collected downwind from three power plants, Tuncel et al. did not see sudden drops in the S/Se ratio that one would expect to see occasionally in fresh plumes from coal-fired plants. A major flaw in the Gor-don/Olmez model is the assumption of uniform vertical concentration profiles, which is surely a poor assumption just beyond a source. Most power plants have tall stacks, whereas, measurements are at ground level. The S/Se ratio will surely be depressed near the plume centerline, but the effect will usually be washed out before the plume hits ground level. However, around cities, there are probably some ground level sources. 

The next experiments are conducted on a 500-pound-per-hour combustor. This combustor, which simulates commercial practice, is shown in Figure 2. It is a wall-fired, dry-bottom unit which uses cyclone ash collection. Where possible both coal and ash samples are obtained from commercial power plants to verify the results from the experimental combustors. The combination of the two programs will hopefully give... 

A high content of sulfates is specific for the samples that were collected in the vicinity of the TPS-1, while a low content was near the TPS-3. The main causes of the difference in the sulfates content are the lifespan of power plants and bad stmctural ratio of used fuels (peat, coal, fuel oil, gas). For example, the fuel oil is predominantly used at the oldest TPS-1 (production activity from 1912) gas is used in a less degree. The relatively new plants TPS-3 n TPS-4 are natural gas-fired the most of the year. 

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