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991.
992.
993.
G. P. Greiner D. A. Furlong D. W. VanOsdell L. S. Hovis 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1125-1130
The concept of electrostatic stimulation of fabric filtration (ESFF) has been investigated at pilot scale. The pilot unit consisted of a conventional baghouse in parallel with an ESFF baghouse, allowing direct comparison. All results reported in this paper are for pulse-cleaned bags in which the electric field was maintained parallel to the fabric surface. The performance of the ESFF baghouse has been superior to the parallel conventional baghouse by several measures. The ESFF baghouse demonstrated: (1) a reduced rate of pressure drop increase during a filtration cycle, (2) lower residual pressure drop, (3) stable operation at higher face velocities, and (4) improved particle removal efficiency. These benefits can be obtained with only minor modifications to conventional pulse-jet hardware and at low electrical power consumption. The indicated ability to operate at increased face velocities with only modest expenditure for electrical hardware leads to very favorable economic projections. 相似文献
994.
Michael Duncan Hinrich L. Bohn Mark Burr 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1175-1179
If many homeowners convert to solid fuels for heating, residential flue gases will be a large source of air pollution. Control of this pollution requires an inexpensive, reliable, and effective method of flue gas treatment. One such method is to force flue gases through soil beds. Such soil treatment removes all detectable smoke, odor, and polynuclear organic matter (POM), up to 97% of the CO, and at least 97% of the SO2 from flue gases of wood and coal combustion. The technique is low cost, reliable, almost maintenance-free, and also appears suitable for other small point sources of air pollution. 相似文献
995.
Robert E. Hall W. Marcus Cooke Rachael L. Barbour 《Journal of the Air & Waste Management Association (1995)》2013,63(7):683-687
Information presented in this paper is directed to individuals concerned with emissions from combustion of waste crankcase oil for space heating. Studies were performed to characterize gaseous and particulate emissions and vaporizing pot solid residues resulting from the combustion of waste crankcase oil. Two types of waste oil burners were tested. One was a vaporizing oil burner rated at 35.2 kW (120,000 Btu/h heat input), and the other was an air atomizing oil burner rated at 73.3 kW (250,000 Btu/h heat input). Except for NOX and SOX, gaseous emissions were similar to those from conventional distillate oil combustion. NOX and SOX emissions were higher due to higher fuel nitrogen and sulfur concentrations. Waste oil from automotive use showed higher inorganic levels than crankcase oil used for truck engine lubrication. Both burner types discharged high levels of metallic species, but the air atomizing unit had much higher stack emission levels than did the vaporizing pot system. Also, particulate loading levels were an order of magnitude higher for the air atomizing burner than for the vaporizing pot burner when firing the waste oils. However, the vaporizing pot burner generated a waste residue containing the majority of its elemental emissions. Elements which exceeded threshold limit values for one or both heaters were cadmium, chromium, cobalt, copper, iron, lead, nickel, phosphorus, and zinc. However, the nickel and much of chromium appeared to be a sampling artifact caused by the stainless steel sampling system. 相似文献
996.
997.
J. S. Evans P. L. Kinney J. L. Koehler D. W. Cooper 《Journal of the Air & Waste Management Association (1995)》2013,63(5):551-553
Abstract There is a dearth of information on dust emissions from sources that are unique to the U.S. Department of Defense testing and training activities. However, accurate emissions factors are needed for these sources so that military installations can prepare accurate particulate matter (PM) emission inventories. One such source, coarse and fine PM (PM10 and PM2.5) emissions from artillery backblast testing on improved gun positions, was characterized at the Yuma Proving Ground near Yuma, AZ, in October 2005. Fugitive emissions are created by the shockwave from artillery pieces, which ejects dust from the surface on which the artillery is resting. Other contributions of PM can be attributed to the combustion of the propellants. For a 155–mm howitzer firing a range of propellant charges or zones, amounts of emitted PM10 ranged from ~19 g of PM10 per firing event for a zone 1 charge to 92 g of PM10 per firing event for a zone 5. The corresponding rates for PM2.5 were ~9 g of PM2.5 and 49 g of PM2.5 per firing. The average measured emission rates for PM10 and PM2.5 appear to scale with the zone charge value. The measurements show that the estimated annual contributions of PM10 (52.2 t) and PM2.5 (28.5 t) from artillery backblast are insignificant in the context of the 2002 U.S. Environment Protection Agency (EPA) PM emission inventory. Using national–level activity data for artillery fire, the most conservative estimate is that backblast would contribute the equivalent of 5 x 10–4% and 1.6 x 10–3% of the annual total PM10 and PM2.5 fugitive dust contributions, respectively, based on 2002 EPA inventory data. 相似文献
998.
Larry G. Felix Randy L. Merritt Kent Duncan 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1075-1085
At the Monticello station, operated by the Texas Utilities Generating Company, lignite coal obtained locally in Titus and Hopkins Counties fuels each of the three units. Units 1 and 2 are identical 575-MW Combustion Engineering (CE) boilers, each of which discharges its effluent to a 36- compartment shake/deflate cleaned baghouse paralleled with four electrostatic precipitators (ESP). Unit 3 is a larger boiler and is followed by an ESP and a scrubber. The Unit 1 and 2 baghouses were designed to clean 80 percent of the flue gas. Since startup, these baghouses have regularly experienced flange-to-flange pressure drops in excess of 10 in. H2O, with large opacity spikes caused by ash bleeding through the bags after compartment cleanings. Because of higher-than-expected pressure drop, the baghouses receive only about 45-50 percent of the flue gas. Analysis has shown the Monticello lignite ash significantly differs from most other coal ashes. Testing has shown that the Monticello ash is not filtered effectively by many "standard" bag materials. However, this testing indicates that there are fabrics that show promise of eliminating the ash bleedthrough with little pressure drop penalty. Testing has also shown that injection of low concentrations (10-15 ppm) of ammonia (NH3) into the flue gas significantly decreases ash bleedthrough, so that with NH3 injection "standard" bag materials may perform adequately. Currently, fullcompartment testing of four fabrics, with and without NH3 injection, is under way at the Unit 1 baghouse. The research conducted at the Monticello station is reviewed in this paper and the encouraging results from the full-compartment tests are presented. 相似文献
999.
Andrew C. VanderZaag Hambaliou Baldé Jemaneh Habtewold Etienne L. Le Riche Stephen Burtt Kari Dunfield 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1096-1106
Liquid manure storages are a significant source of methane (CH4) emissions. Farmers commonly agitate (stir) liquid manure prior to field application to homogenize nutrients and solids. During agitation, manure undergoes mechanical stress and is exposed to the air, disrupting anaerobic conditions. This on-farm study aimed to better understand the effects of agitation on CH4 emissions, and explore the potential for intentional agitation (three times) to disrupt the exponential increase of CH4 emissions in spring and summer. Results showed that agitation substantially increased manure temperature in the study year compared to the previous year, particularly at upper- and mid-depths of the stored manure. The temporal pattern of CH4 emissions was altered by reduced emissions over the subsequent week, followed by an increase during the second week. Microbial analysis indicated that the activity of archaea and methanogens increased after each agitation event, but there was little change in the populations of methanogens, archaea, and bacteria. Overall, CH4 emissions were higher than any of the previous three years, likely due to warmer manure temperatures that were higher than the previous years (despite similar air temperatures). Therefore, intermittent manure agitation with the frequency, duration, and intensity used in this study is not recommended as a CH4 emission mitigation practice.Implications: The potential to mitigate methane emissions from liquid manure storages by strategically timed agitation was evaluated in a detailed farm-scale study. Agitation was conducted with readily-available farm equipment, and targeted at the early summer to disrupt methanogenic communities when CH4 emissions increase exponentially. Methane emissions were reduced for about one week after agitation. However, agitation led to increased manure temperature, and was associated with increased activity of methanogens. Overall, agitation was associated with similar or higher methane emissions. Therefore, agitation is not recommended as a mitigation strategy. 相似文献
1000.
Experimental Characterization of Atmospheric Diffusion in Complex Terrain with Land-Sea Interactions
M. M. Mill´n E. Otamendi L. A. Alonso I. Ureta 《Journal of the Air & Waste Management Association (1995)》2013,63(7):807-811
The body of information presented in this paper is directed to scientists working in atmospheric dispersion research and model development. Two years of field measurements in the coastal area of Bilbao in northern Spain show that the diffusion behavior in this complex terrain can be classified into several well defined patterns, which correspond to certain meteorological conditions. The approach taken has been the systematic use of SO2 remote sensors (COSPEC) and ground level monitors in moving platforms which are used to follow and document the flow of the air mass. Results to date show that complex reentry cycles can occur and that synoptically different flows may be indistinguishable by wind sensors at ground level (affected by channeling), and yet result in totally different observed pollution levels by a fixed monitoring network (affected by topographical effects). These results are being used to parameterize the cause-effect relationships and guide the modeling efforts in this area of complex terrain. 相似文献