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851.
A new approach for state- and utility-level analysis of the cost and regional economic impacts of strategies for reducing utility SO2 emissions is summarized and applied to Ohio. The methodology is based upon probabilistic production costing and economic input-output analysis. It is an improvement over previous approaches because it: (1) accurately models random outages of generating units, “must-run” constraints on unit output, and the distribution of power demands; and (2) runs quickly on a microcomputer and yet considers the entire range of potential control strategies from a systems perspective. The input-output analysis considers not only the economic effects of utility fuel use and capital investment, but also those of increased electric rates. Two distinct strategies are found to be most attractive for Ohio. The first, more flexible one, consists of emissions dispatching (ED) alone to meet short run emissions reduction targets. A 75 percent reduction can then be achieved by the turn of the century by combining ED and fuel switching (FS) with flue gas desulfiirization, limestone Injection multistage burners, and physical coal cleaning at selected plants. The second is a scrubber-based strategy which includes ED. By the year 2000, energy conservation becomes a cost effective component of these strategies. In order to minimize compliance costs, acid rain legislation which facilitates emissions trading and places regional tonnage limits on emissions is desirable.  相似文献   
852.
Abstract

The collapse of the World Trade Center (WTC) on September 11, 2001, generated large amounts of dust and smoke that settled in the surrounding indoor and outdoor environments in southern Manhattan. Sixteen dust samples were collected from undisturbed locations inside two uncleaned buildings that were adjacent to Ground Zero. These samples were analyzed for morphology, metals, and organic compounds, and the results were compared with the previously reported outdoor WTC dust/smoke results. We also analyzed seven additional dust samples provided by residents in the local neighborhoods. The morphologic analyses showed that the indoor WTC dust/smoke samples were similar to the outdoor WTC dust/smoke samples in composition and characteristics but with more than 50% mass in the <53 μm size fraction. This was in contrast to the outdoor samples that contained >50% of mass above >53 μm. Elemental analyses also showed the similarities, but at lower concentrations. Organic compounds present in the outdoor samples were also detected in the indoor samples. Conversely, the resident-provided convenience dust samples were different from either the WTC indoor or outdoor samples in composition and pH, indicating that they were not WTC-affected locations. In summary, the indoor dust/smoke was similar in concentration to the outdoor dust/smoke but had a greater percentage of mass <53 μm in diameter.  相似文献   
853.
Abstract

The U.S. Department of Defense approved activities conducted at the Utah Test and Training Range (UTTR) include both operational readiness test firing of intercontinental ballistic missile motors as well as the destruction of obsolete or otherwise unusable intercontinental ballistic missile motors through open burn/open detonation (OB/ OD). Within the Utah Division of Air Quality, these activities have been identified as having the potential to generate unacceptable noise levels, as well as significant amounts of hazardous air pollutants. Hill Air Force Base, UT, has completed a series of field tests at the UTTR in which sound-monitoring surveillance of OB/OD activities was conducted to validate the Sound Intensity Prediction System (SIPS) model. Using results generated by the SIPS model to support the decision to detonate, the UTTR successfully disposed of missile motors having an aggregate net explosive weight (NEW) of 56,500 lbs without generating adverse noise levels within populated areas. These results suggest that, under appropriate conditions, missile motors of even larger NEW may be detonated without exceeding regulatory noise limits. In conjunction with collecting noise monitoring data, air quality data was collected to support the development of air emission factors for both static missile motor firings and OB/OD activities. Through the installation of 15 ground-based air samplers, the generation of combustion fixed gases, hazardous air pollutants, and chlorides were monitored during the 56,500-lb NEW detonation event. Comparison of field measurements to predictions generated from the U.S. Navy’s energetic combustion pollutant formation model, POLU4WN, indicated that, as the detonation fireball expanded from ground zero, organic compounds as well as carbon monoxide continued to oxidize as the hot gases reacted with ambient air. Hazardous air pollutant analysis of air samplers confirmed the presence of chloromethane, benzene, toluene, 1,2-propadiene, and 2-methyl-1-propene, whereas the absence of hydrogen chloride gas suggested that free chlorine is not generated during the combustion process.  相似文献   
854.
Abstract

The U.S. Department of Defense-approved activities conducted at the Utah Test and Training Range (UTTR) include both operational readiness test firing of intercontinental ballistic missile (ICBM) motors, as well as the destruction of obsolete or otherwise unusable ICBM motors through open burn/open detonation (OB/OD). Within the Utah Division of Air Quality, these activities have been identified as having the potential to generate unacceptable noise levels, as well as significant amounts of volatile organic compounds (VOCs). Hill Air Force Base, UT, has completed a series of field tests at the UTTR in which sound-monitoring surveillance of OB/OD activities was conducted to validate the Sound Intensity Prediction System (SIPS) model. Using results generated by the SIPS model to support the decision to detonate, the UTTR successfully disposed of missile motors having an aggregate net explosive weight (NEW) of 81,374 lb without generating adverse noise levels within populated areas. In conjunction with collecting noise-monitoring data, air emissions were collected to support the development of air emission factors for both static missile motor firings and OB/OD activities. Through the installation of 15 ground-based air samplers, the generation of combustion-fixed gases, VOCs, and chlorides was monitored during the 81,374-lb NEW detonation event. Comparison of field measurements to predictions generated from the US Navy energetic combustion pollutant formation model, POLU4WN, indicated that, as the detonation fire ball expanded, organic compounds, as well as CO, continued to oxidize as the combustion gases mixed with ambient air. VOC analysis of air samplers confirmed the presence of chloromethane, vinyl chloride, benzene, toluene, and 2-methyl-1-propene. Qualitative chloride analysis indicated that gaseous HCl was generated at low concentrations, if at all.  相似文献   
855.
Hydrous ferric oxide (here termed ‘ochre’) sludge, an abundant waste product produced from the treatment of acid mine drainage (AMD), was used in this study for the removal of phosphorus (in the form of phosphate ions) from contaminated waters. The phosphorus uptake capacities of both raw and pelletized AMD solids were compared using batch and column tests. Addition of a cement binder to the AMD solids during pellet production led to significantly increased P-loading of the resultant solids compared to the raw sludge. Additionally, the pellets were found to continue to remove P in tests up to 7 d in duration whereas the unbound AMD sludge appeared to approach equilibrium with phosphate solution after approximately 60 min of contact time. In line with previous studies P uptake by the AMD solids was found to be primarily via adsorption. By contrast calcium phosphate precipitation was found to be the dominant removal mechanism for the cement-bound ochre pellets with a relatively small proportion of removal attributable to the AMD solids. SEM–EDX analysis of the surface of used pellets showed a Ca:P molar ratio close to that of hydroxyapatite (HAP). Continuous column tests on these pellets showed a rapid decrease in P removal capacity by the pellets over time, attributable to the formation of a passivating HAP surface layer.  相似文献   
856.
Sampling for nitrogen and sulfur dioxides was initiated at several National Air Sampling Network stations in 1959 using a sampler developed for that purpose. In 1961 the Gas Sampling Network was expanded to its maximum of 49 stations. Sampling equipment and collecting solutions are supplied and chemical analyses performed by the network laboratories. Sampling and analysis procedures are described briefly. Average and maximum 24-hour concentrations of nitrogen dioxide and sulfur dioxide observed at 48 stations during 1961-1963 are presented.  相似文献   
857.
Recent air pollution legislation, introduced as a Clean Air Act into New South Wales, the most populous and most heavily industrialized Australian State relies mainly upon the establishment of maximum limits of emission of air impurities. Regulations made under the Act set out the first of a series of such limits which cover the more commonly encountered pollutants. Other limits will be included later as knowledge is accumulated but, in the meantime, where standards have not been fixed the "best practicable means" of controlling air pollution must be used. To facilitate administration and to provide financial support for scientific and engineering services in the form of the Air Pollution Control Board, industries of significant air pollution potential have been designated as scheduled premises and pay annual license fees. Further technical support for the legislation is provided by an Air Pollution Advisory Committee.  相似文献   
858.
The body of information presented In this paper is directed to those Individuals involved In research on, or the design of, electrostatic precipitators. A model for calculating collection efficiencies— one based solely on physical principles and, as a result, one requiring no prior Information from pilot plant or field testing—has been employed to generate performance curves for twelve Industries presently using electrostatic precipitators. These industries Include the electric power, cement, pulp and paper, steel, chemical, and petroleum industries. The performance curves describe the predicted collection efficiency as a function of preclpltator length, plate-to-plate spacing and average field strength, and are presented In graphical, tabular, and equation form. Wherever literature values for a particular Industry are available, comparisons are made between the collection efficiencies generated by the new model and those based on actual preclpltator performance. The two are generally found to be In reasonable agreement.

The use of the Deufsch-Anderson model for preclpltator design Is also discussed. Results from the new model demonstrate that collection efficiency Is sensitive to particle size distribution, a complication that cannot be easily treated In the Deutsch-Ander-son equation which, In Its unmodified form, requires the use of a single representative particle size. It is concluded that the new model Is potentially a more realistic and viable approach to the prediction of collection efficiencies and as such should prove to be a valuable aid in electrostatic preclpltator design.  相似文献   
859.
Examination of total deaths in New York City by day of occurrence shows periodic peaks in mortality which are associated with periods of high air pollution. These peaks are usually associated with periods of low wind speed and temperature inversion conditions which permit air pollution to build up to high levels. Unlike the experience of London, fog is not a necessary part of this picture, and therefore the presence of these episodes is often not apparent at the time to most inhabitants. A characteristic feature of these episodes is the immediate rise in mortality occurring on the same day as the peaks of pollution. A second characteristic is their frequent influence on death rates in the 45–64 year age group as well as in those over 65. These characteristics suggest that if these excess deaths are related to air pollution (as we believe to be highly likely) the mechanism is probably protean and pervasive affecting the course of a variety of different diseases through a basic physiologic effect. The relationship of morbidity in a normal urban population to air pollution is also demonstrated by time series analysis of correlation coefficients. The relation of two symptoms (cough and eye irritation) in a group of 1090 persons observed for three years is compared with two measures of air pollution (SO2 and particulate density) to which they were exposed. Time lags of up to 28 days were introduced and a constant relationship between air pollution levels and those symptoms was demonstrated.  相似文献   
860.
On June 18, 19, and 20, 1970, two aircraft, a rawinsonde, two pibal stations, and four ground stations provided simultaneous samples of total oxidant, temperature, and winds up to 8000 ft in an area extending from Santa Monica, Calif., east to Redlands and north across the San Bernardino Mountains. It was shown that photochemical oxidant formed in the marine layer is vented up the slopes and over the crest of the San Bernardino Mountains during the day. Layers of high oxidant concentrations were detected above the inversion base, suggesting that some pollution is vented up the slopes and subsequently advected back to the south. The diurnal changes in the temperature inversion also contribute to the high concentration found above the inversion base. These processes result in multi-layers of pollution. The study suggests that oxidant air pollution is transported up to 80 mi to forested mountains, where severe damage to conifer species has been documented.  相似文献   
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