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901.
R.E. George J.S. Nevitt J.A. Verssen 《Journal of the Air & Waste Management Association (1995)》2013,63(7):507-515
This paper is directed to those concerned with the air environment and its degradation by the burden of pollution from jet aircraft operations. A summary is presented of the results of a comprehensive air pollution study of jet aircraft operations at the Los Angeles International Airport (LAX). Included in the data obtained from this study are jet engine exhaust measurements for currently used turboprop, turbojet and turbofan engines; measurements of specific contaminants in the atmosphere inside and outside of passenger terminals and ticketing areas, and in aircraft cabins during ground operations including passenger loading and taxiing prior to takeoff; also presented are ambient air measurements in a two-mile radius of the airport. An evaluation is made of the emissions of contaminants from air transport operations and all related ground activities including motor vehicles, that contribute to the total atmospheric contaminant burden at the airport. 相似文献
902.
N.C.G. Freeman T. Wainman P.J. Lioy A.H. Stern S.I. Shupack 《Journal of the Air & Waste Management Association (1995)》2013,63(8):604-605
Honorary Memberships are conferred by the Air Pollution Control Association on persons of widely recognized eminence in some part of the field of air pollution control or who have rendered especially meritorious service to the Association. Honorary Memberships were awarded this year to Dr. Leonard Greenburg and Mr. Milton Reizenstein, both past presidents of APCA. 相似文献
903.
Ralph C. Sklarew Allan J. Fabrick Judith E. Prager 《Journal of the Air & Waste Management Association (1995)》2013,63(11):865-869
A new method for solving the turbulent atmospheric diffusion equation has been developed based on Lagrangian mass points, or particles moving through an Eulerian grid. The method is one of a family of Particle-/n-Cell techniques but is a unique extension to incorporate the effects of turbulent diffusion based on K-theory; thus the acronym PICK. In the three-dimensional computer-aided model, NEXUS (Numerical EXamination of Urban Smog), this method has been applied to simulation of carbon monoxide (CO) in Los Angeles. For CO the NEXUS simulation was within 20% of observed day-averaged concentrations at 12 stations and the hour-averages were also in good agreement. This model was extended to include the effects of photochemical smog in Los Angeles. The results of the photochemical simulation were also qualitatively correct due to rapid NO to NO2 conversion in the simulation. 相似文献
904.
Michael J. Pilat 《Journal of the Air & Waste Management Association (1995)》2013,63(2):176-178
Theoretical calculations and experimental measurements show that the collection of small aerosol particles (0.05 to 5 micron diameter range) by water droplets in spray scrubbers can be substantially increased by electrostatically charging the droplets and particles to opposite polarity. Measurements with a 140 acfm two chamber spray scrubber (7 seconds gas residence time) showed an increase in the overall particle collection efficiency from 68.8% tit uncharged conditions to 93.6% at charged conditions, with a dioctyl phthalate aerosol (1.05 μm particle mass mean diameter and 2.59 geometric standard deviation). The collection efficiency for 0.3 μm particles increased from 35 to 87% when charged. During 1973–1974 a 1000 acfm pilot plant electrostatic scrubber was constructed inside a 40 ft trailer for evaluation on controlling particu-late emissions from pulp mill operations (funded by Northwest Pulp and Paper Association). Field tests performed on the particle emissions exhausting from SO2 absorption towers treating the gases from a magnesium based sulfite recovery boiler have shown particle collection efficiencies ranging from about 60 to 99% by weight, depending on the electrostatic scrubber operating conditions. Energy requirements for the University of Washington electrostatic scrubber are about 0.5 hp/1000 acfm (350 Watts/1000 acfm) including gas pressure drop, water pressure drop, and electrostatic charging of the water spray droplets and the particles. 相似文献
905.
Laurel J. Staley Marta K. Richards George L. Huffman Robert A. Olexsey Barry Dellinger 《Journal of the Air & Waste Management Association (1995)》2013,63(3):321-331
Measurements conducted on full-scale hazardous waste incinerators have occasionally shown a relationship between carbon monoxide (CO) emissions and emissions of toxic organic compounds. In this study, four mixtures of chlorinated C1 and C2 hydrocarbons were diluted in commercial-grade heptane and burned in a water-cooled turbulent flame reactor (TFR) under two different excess air levels. No correlation between CO and organic emissions could be discerned. Reasons for this lack of observable correlations are discussed in terms of combustion and chemical reaction kinetic theory. 相似文献
906.
R. A. Stoehr J. P. Pezze 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1119-1122
The evolution of H2S and SO2 from hot blast furnace slags by reaction with H2O has been found to be dependent upon the presence of O2 or H2 in the reaction zone as well as on the temperature. H2 has been found to produce a small increase in H2S and a small decrease in SO2 emission, while O2 has been found to produce a very great inhibiting effect on H2S emission and only a small increase in SO2 emission. The total emission of sulfur bearing gases is much less when H2O + air is blown at the slag than when H2O + Ar is blown at the slag, particularly at 1200°C and above. These effects may be useful in attempts to design systems for slag quenching which will produce less pollution. 相似文献
907.
Edward J. Calabrese Alfred Sorensen 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1254-1256
In an article published in the August 1975, Journal of the Air Pollution Control Association entitled “Methylcyclopentadienyl Manganese Tricarbonyl as an Antiknock: Composition and Pate of Manganese Exhaust Products,” the authors conclude that, “… use of MMT in gasoline will result in no public health hazards, because of the low toxicity of manganese and because of the very low concentration of MMT that would be used in gasoline …. If all gasoline contained 0.1 g Mn/gal, the amount of airborne Mn its exhaust would contribute to urban areas would contribute to urban areas would be only 0.02-0.2 μg/m3, with a median value of 0.05 μg/m3.” 相似文献
908.
J. Stuart Fordyce Dean W. Sheibley 《Journal of the Air & Waste Management Association (1995)》2013,63(7):721-724
Samples of ASTM type A jet fuel were analyzed for trace element content by instrumental neutron activation techniques. Forty-nine elements were sought. Only ten, aluminum, gold, indium, lanthanum, titanium, vanadium, barium, dysprosium, tellurium, and uranium, were observed at levels above the detection limits encountered; of these only aluminum, titanium, and barium were present at concentrations greater than 0.1 ppm. Estimates of exhaust gas. concentrations are made, and the ambient contribution at or near airports is calculated by using the Los Angeles International Airport dispersion model. It is shown that the ambient contribution is about an order of magnitude below typical urban levels for virtually all elements sought. 相似文献
909.
Edward J. Lillis Dexter Young 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1015-1018
The various aspects of two similar but indeed different air pollution problems are discussed. Both fugitive emissions (industrial) and fugitive dust emissions represent problems affecting attainment of national standards. Both are difficult to quantify so as to determine the relative magnitude of the problem. Both have been generally overlooked in the past in relation to developing an effective and widespread air pollution control program. Both problems will generally require the use of non-conventional air pollution control measures. Both are also becoming the subject of more intensive investigation as more knowledge is being gathered to implicate such emissions as significant air pollution problems. 相似文献
910.
J.I. Accortt A. L Plumley J.R. Martin 《Journal of the Air & Waste Management Association (1995)》2013,63(10):966-969
This paper includes results from pilot plant studies and early field demonstration units and a discussion of the application of the limestone wet scrubbing process to a low sulfur syb-butuminous coal. This latter application required the development of a hybrid two stage scrubber to enable collection of the fine particulate matter as well as removal of a significant amount of the sulfur dioxide. 相似文献