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901.
Larry D. Johnson M. Rodney Midgett Ruby H. James Michael M. Thomason M. Lisa Manier 《Journal of the Air & Waste Management Association (1995)》2013,63(5):709-713
The body of information presented in this paper is directed to those individuals concerned with developing or implementing screening strategies for characterizing organic emissions from incinerators and other combustion sources. The need to characterize hazardous waste incinerator emissions for multiple organic compounds has been steadily increasing for several years. The regulatory approach makes use of a type of indicator compound procedure that concentrates on principal organic hazardous constituents (POHCs). In addition to continuing interest in POHCs, interest has been growing in the types and concentrations of products of incomplete combustion (PICs). Sampling and analysis methods have been developed previously for approximately 225 of the more important POHCs and PICs. These methods may be used as components of a cost-effective screening protocol aimed at maximum characterization of emissions, whether the project budget is large or small. This paper contains a discussion of fundamental principles of several kinds of screening strategies and recommends an approach suitable for incinerators and other combustion sources. The concept of a risk-driven analysis strategy is introduced and illustrated with a simplified example. 相似文献
902.
903.
Stephen C. James Donald E. Sanning 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1178-1184
The problem of contamination to land and groundwater from improper handling of hazardous materials/ waste is faced by all countries. Also, the need for reliable, cost-effective technologies to address this problem at contaminated sites exists throughout the world. Many countries have only started to develop new innovative/ alternative technologies while others have already started to apply these technologies to the cleanup of contaminated sites. The purpose of this NATO/ CCMS (North Atlantic Treaty Organization/Committee for the Challenges to Modern Society) Pilot Study is to discuss and evaluate new innovative/alternative technologies and/or existing systems that may be applicable to the cleanup of contaminated sites. Through this pilot study, the exchange of information on new and existing technologies for dealing with problem hazardous waste sites is promoted. The pilot study is made up of an international group of experts drawn from the participating countries. The study, which was initiated in 1986, is planned to last five years. It is piloted by the United States and copiloted by the Federal Republic of Germany (FRG) and The Netherlands. This report includes an overview and history of the NATO/CCMS Pilot Study, but it primarily presents a documentation of the NATO/CCMS Second International Conference on the Demonstration of Remedial Action Technologies for Contaminated Land and Groundwater held in Bilthoven, The Netherlands on November 7-11,1988. 相似文献
904.
Ronald P. Young James L. DuBard Leslie E. Sparks 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1518-1522
Part I of this work has shown that electrical breakdown in dust layers obeys Paschen's Law, but occurs at applied field values which appear too small to initiate the breakdown. In this paper we will show how an effective dielectric constant characterizing the dust layer can be determined from ac dielectric measurements and the theory of Debye. When combined with an expression for the enhanced local electric field in the void spaces between particles in the layer, field strengths which are large enough to initiate electrical breakdown in the layer are predicted at relatively low values of applied field. The effect of temperature and dust layer thickness on the onset of electrical breakdown within the dust layer can also be explained by the dependence of the effective dielectric constant on these parameters. 相似文献
905.
Bradley J. Ingebrethsen David L. Heavner Anthony L. Angel James M. Conner Thomas J. Steichen C. R. Green 《Journal of the Air & Waste Management Association (1995)》2013,63(4):413-417
Particulate mass concentration measurements have been made on environmental tobacco smoke (ETS) for the purpose of assessing the relative accuracy of several measurement procedures. ETS over a range of concentrations was generated in an environmental chamber by three methods. Mass concentration was measured by a gravimetric/spectrophotometric collection procedure, piezoelectric particle mass monitors, two nephelometry-based mass monitors, and a particle counting and sizing system. Two-hour average mass concentrations were determined by each method for concentrations ranging from very low levels up to those achieved by smoking one entire cigarette in the chamber. Statistical comparisons were made among procedures employing the gravimetric filter measurement as the basis for comparison. One nephelometry-based procedure gave significantly higher and the other significantly lower values than the filter determination. In one case, a correction for the difference between the particle mass density of the calibrating aerosol and that of ETS brought the nephelometry-based procedure into reasonable agreement with the filter measurement, while for the other, the correction did not resolve the discrepancy between methods. Statistically significant differences between the responses of two supposedly identical piezoelectric mass monitors were found, as was some slight dependence of the nephelometry- based procedures on method of ETS generation. In summary, the results indicate that significant errors can be expected if the instruments studied are used “off the shelf,” even for ETS generated under controlled laboratory conditions. Caution should be employed in field measurements where numerous sources and types of particulate matter can be encountered. 相似文献
906.
James H. Turner Andrew S. Viner Richard E. Jenkins William M. Vatavuk John D. McKenna 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1105-1112
This is the second of a two-part article that reviews baghouse filtration theory, presents size estimating methods, and gives costing procedures for a variety of baghouse types and sizes. Part I of the article discussed theory and sizing; this part presents costing. Information is given for estimating total capital investment including separate costs for the bare baghouse (five types), bags, and, where needed, cages and Venturis. Factors are given for installation and for indirect costs. Direct and indirect annual costs are discussed. An example problem is given. The material in this article is taken primarily from the EAB Control Cost Manual. 相似文献
907.
J. D. Coons H. A. James H. C. Johnson M. S. Walker 《Journal of the Air & Waste Management Association (1995)》2013,63(5):199-203
The Bay Area Air Pollution Control District adopted a regulation limiting plume visibility in terms of the Ringelmann Chart and also in terms of obscuration of the observer’s view. Since both limitations were adopted in terms requiring the judgment of an observer, preparation for enforcement required development and calibration of a training unit, so that inspectors could be qualified to testify as expert witnesses under this regulation. This paper summarizes the design, calibration and use of the training unit developed for this purpose. 相似文献
908.
James P. Lodge Jr. John B. Pate Blair E. Ammons Glenda A. Swanson 《Journal of the Air & Waste Management Association (1995)》2013,63(4):197-200
Hypodermic needles are useful as convenient low-cost critical orifices to control the flow rate in air sampling. Variations in flow rate were less than five per cent for 41 needle gauge-length combinations. To provide maximum accuracy, a simple calibration procedure is described. Needles may be reused more than six times, if protected. Types of protectors are described. Resistances of protector, collector, and prefilter combinations affect criticality at nine liters/min. Simple sampling devices using needles as orifices are described. 相似文献
909.
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
910.
James M. Shikiya Robert D. MacPhee 《Journal of the Air & Waste Management Association (1995)》2013,63(12):943-945
Three different recording analyzers for sulfur dioxide were operated in parallel under field conditions. Manual sampling for sulfur dioxide using the West-Gaeke procedure supplemented the instrumental evaluation tests. Two of the analyzers were of the continuous-flow type. These were found to give markedly higher readings for SO2 in the atmosphere (in some cases as much as threefold) than did the other recorder which was sequential-batch or the West-Gaeke manual method. 相似文献