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891.
892.
At the Clairton Coke Works of the United States Steel Corporation (the world’s largest coke plant), with coal charges of about 30,000 net tons per day, a system designated as “stage charging” has been developed for charging coal into the coke oven chamber without emissions to the atmosphere. The principles of the system are based on controlled sequential flow of the coal from the charging hoppers, during which the oven chamber is maintained under a very slight negative pressure condition by use of steam aspiration in the offtakes for on-the-main charging. The techniques are basic but require knowledge of the coal characteristics, adequate and properly maintained aspirating systems, including clean offtake piping, control of coal volume in the individual hoppers, and last, and probably most important, adherence by the operating crew to specific charging and leveling practices.  相似文献   
893.
A study was conducted to evaluate performance and cost comparisons of fabric filters and alternate fine particulate control techniques. In relating the removal of fine particulate to costs, due to the lack of fractional efficiency data, it was found necessary to treat a specific application in order to make the study manageable. The case chosen is that of the coal fired industrial boiler since Enviro-Systems has a pilot program in this application area.  相似文献   
894.
As many of you know, I previously served as Deputy Administrator of the Environmental Protection Agency at a time when the problem of air pollution control was reaching a peak of public awareness. The work of the Air Pollution Control Association in investigating facts and accelerating the development of solutions earned my high respect then and my continued admiration now.  相似文献   
895.
The body of information presented in this paper is directed to design engineers, operating management and others who may be concerned with the prevention of atmospheric emissions from electric arc steelmaking furnaces. Inland Steel Co. has recently begun operating its first electric furnace shop. Air pollution control equipment for the shop was installed to meet or exceed the legal requirements of applicable air pollution ordinances and regulations. General shop production requirements were established at 100 tons of steel per hour (maximum) to meet sales forecasts and intermediate production facility requirements. Conventional swing roof furnace design was selected for the pair of furnaces in the shop.  相似文献   
896.
The Environmental Protection Agency has recommended or specified methods for the measurement of participate concentrations in flue gases. The EPA Train for this measurement originally comprised two segments: the front half and the impinger train downstream from the filter proper. This review examines the controversial areas implicit in the use of this EPA Train or the revised EPA train which eliminates the impinger train.  相似文献   
897.
Noontime visibilities in downtown Los Angeles, averaged over the smog season of June through November, show two cycles of general deterioration and improvement. The improvement since 1962 is confirmed by available high volume filter data and conditions in 1974/75 are at least as good as at anytime since observations were begun in 1933. The decrease in frequency of “rule 57” days suggests that the improvement of the last decade and perhaps the cyclic variation of the past 40 years has been primarily of meteorological origin.  相似文献   
898.
There are doubts concerning the sources of the pollutant ozone in an urban location. Current control regulations,1 for example, are based on local sources. Many studies suggest that plumes of pollutants released by upwind areas are the cause. For example, New York City has been associated with high O3 in New England,2 Chicago with O3 in Milwaukee,3 and St. Louis with O3 in rural Illinois.4 Others5,6 have suggested the problem must be treated on a synoptic scale. In an effort to understand the problem at Indianapolis better, a series of experiments involving aircraft flights were conducted in the Indianapolis area and their results are herein reported. Specifically, a cross country flight of over 100 mi both to the northeast and southwest of Indianapolis, a vertical spiral to 28,000 ft, low level data associated with takeoff and landing of the aircraft, and ground data at four sites, are available for the afternoon of June 9,1976.  相似文献   
899.
Two processes are currently being employed in North America for the desulfurization of coke oven gas, the Vacuum Carbonate System, and the Stretford System. A third, the Sulfi-ban Process, which was recently announced, now has several plants scheduled for construction. Overall operating requirements for each of these processes are considered in detail. Emphasis is placed on an identification of power and steam requirements, the types and amounts of solid and/or liquid waste streams produced together with methods for their treatment, and the net desulfurization efficiencies achieved by each process. Detailed estimates of capital and operating costs for desulfurization are considered, and equipment needs for environmental control requirements are discussed.  相似文献   
900.
Calculations of pollutant concentrations at various downwind and crosswind distances from an elevated point source are frequently based on diffusion models and parameter values contained in Turner’s Workbook of Atmospheric Dispersion Estimates.1 These calculations can be made much more speedily on a computer or on a currentgeneration, programmable desk calculator, if the values of the horizontal and vertical standard deviations of plume concentrations distributions are stated explicitly as a mathematical function of downwind distance. The alternative is to read the values from Turner’s Figures 3-2 and 3-3 and input them into the calculation for each individual value of downwind distance.  相似文献   
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