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Hazardous Air Pollutants (hazardous + air_pollutant)
Selected AbstractsHazardous air pollutants emission from coal and oil-fired power plantsASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2010Deepak Pudasainee Abstract Hazardous air pollutants (HAPs) emission characteristics from coal (anthracite, bituminous) and oil-fired power plants were studied in order to control pollutants by formulating US maximum achievable control technology (MACT)-like regulation in Korea. Sampling and analysis were carried out according to either Korean standard test method or US EPA method. Relatively lower levels of NOx and SOx were emitted from plants burning bituminous than the anthracite coal. Less dust was emitted from oil-fired power plants. Mercury, lead, and chromium were dominant in coal-fired power plants, following which, nickel and chromium were emitted from oil-fired power plants. The major volatile organic compounds (VOCs) emitted from coal-fired plants were 1,2-dichloroethane, benzene, carbon tetrachloride, chloroform, trichloro-ethylene. The emission of mercury and other heavy metals in flue gas was attributed to fuel types, operating conditions, residence time in the control devices and air pollution control devices configuration. After emission tests in the field and on analysis of the continuous emission monitoring data collected from facilities under operation and consideration of other various factors, management guidelines will be suggested with special reference to US MACT-like regulation. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Photocatalytic oxidation of methanol using silica-titania composites in a packed-bed reactorENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 4 2006Jennifer M. Stokke Abstract The processing of forest products into pulp, paper, paperboard, and other wood products results in the generation of volatile organic compounds (VOCs) and hazardous air pollutants (HAPs). This work focused on the development of a photocatalytic packed-bed reactor for the oxidation of methanol, which is the primary constituent in high volume low concentration gases emitted from pulp and paper mills. Bench-scale studies using an annular reactor packed with silica-titania composite (STC) pellets were conducted to maximize methanol removal and minimize the formation of byproducts, such as formaldehyde. Parameters such as STC pore size (ca. 40, 120, and 260 Å) and UV wavelength (UVA and UVC) were varied. In the dark, the STC pellets removed methanol via adsorption and had a finite adsorption capacity dependent on the surface area of the composite. When irradiated with UV light, the STC pellets adsorbed and oxidized methanol simultaneously. At the bench-scale, 40 Å STC pellets irradiated with UVC light achieved the greatest methanol removal (ca. 90%) with minimal byproduct formation (i.e., effluent formaldehyde concentration was <1 ppmv). Based on these results, a 40 acfm pilot reactor was fabricated and achieved methanol removal rates up to 66% ± 7% with <1 ppmv formaldehyde production at steady state. © 2006 American Institute of Chemical Engineers Environ Prog, 2006 [source] Air Pollution from Secondary Aluminum Production: Determining the Applicability of MACT RequirementsENVIRONMENTAL QUALITY MANAGEMENT, Issue 4 2001Mario G. Cora EPA's Maximum Achievable Control Technology rule for secondary aluminum production is intended to substantially reduce emissions of hazardous air pollutants. It may also impose significant costs on affected facilities. © 2001 John Wiley & Sons, Inc. [source] Bioprocesses for the removal of nitrogen oxides from polluted airJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2005Yaomin Jin Abstract Nitrogen oxides (NOx) of environmental concern are nitrogen monoxide (NO) and nitrogen dioxide (NO2). They are hazardous air pollutants that lead to the formation of acid rain and tropospheric ozone. Both pollutants are usually present simultaneously and are, therefore, called NOx. Another compound is N2O which is found in the stratosphere where it plays a role in the greenhouse effect. Concern for environmental and health issues coupled with stringent NOx emission standards generates a need for the development of efficient low-cost NOx abatement technologies. Under such circumstances, it becomes mandatory for each NOx-emitting industry or facility to opt for proper NOx control measures. Several techniques are available to control NOx emissions: selective catalytic reduction (SCR), selective non-catalytic reduction (SNCR), adsorption, scrubbing, and biological methods. Each process offers specific advantages and limitations. Since bioprocesses present many advantages over conventional technologies for flue gas cleaning, a lot of interest has recently been shown for these processes. This article reviews the major characteristics of conventional non-biological technologies and recent advances in the biological removal of NOx from flue gases based on the catalytic activity of either eucaryotes or procaryotes, ie nitrification, denitrification, the use of microalgae, and a combined physicochemical and biological process (BioDeNOx). Relatively uncomplicated design and simple operation and maintenance requirements make biological removal a good option for the control of NOx emissions in stationary sources. Copyright © 2005 Society of Chemical Industry [source] The Watershed Deposition Tool: A Tool for Incorporating Atmospheric Deposition in Water-Quality Analyses,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2009Donna B. Schwede Abstract:, A tool for providing the linkage between air and water-quality modeling needed for determining the Total Maximum Daily Load (TMDL) and for analyzing related nonpoint-source impacts on watersheds has been developed. Using gridded output of atmospheric deposition from the Community Multiscale Air Quality (CMAQ) model, the Watershed Deposition Tool (WDT) calculates average per unit area and total deposition to selected watersheds and subwatersheds. CMAQ estimates the wet and dry deposition for all of its gaseous and particulate chemical species, including ozone, sulfur species, nitrogen species, secondary organic aerosols, and hazardous air pollutants at grid scale sizes ranging from 4 to 36 km. An overview of the CMAQ model is provided. The somewhat specialized format of the CMAQ files is not easily imported into standard spatial analysis tools. The WDT provides a graphical user interface that allows users to visualize CMAQ gridded data and perform further analyses on selected watersheds or simply convert CMAQ gridded data to a shapefile for use in other programs. Shapefiles for the 8-digit (cataloging unit) hydrologic unit code polygons for the United States are provided with the WDT; however, other user-supplied closed polygons may be used. An example application of the WDT for assessing the contributions of different source categories to deposition estimates, the contributions of wet and dry deposition to total deposition, and the potential reductions in total nitrogen deposition to the Albemarle-Pamlico basin stemming from future air emissions reductions is used to illustrate the WDT capabilities. [source] Outdoor exposure to airborne polycyclic organic matter and adverse reproductive outcomes: A pilot studyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2001Zdravko P. Vassilev MD Abstract Background To investigate the association between outdoor airborne polycyclic organic matter (POM) and adverse reproductive outcomes in New Jersey, we used a cross-sectional design combining air quality data from the USA EPA Cumulative Exposure Project and individual data on pregnancy outcomes from birth and fetal death certificates at the census tract level. Methods After excluding plural births and chromosomal anomalies, 221,406 live births and 1,591 fetal deaths registered in New Jersey during the years of 1990 and 1991 were included. The exposure estimates were derived from modeled average POM concentrations for each census tract in the state. Results After adjustment for potential confounders, the odds ratios (OR) for very low birth weight for the highest exposure compared to the lowest exposure group was 1.31 (95% CI 1.15,1.51); among term births, high POM exposure was associated with low birth weight OR,=,1.31 (95% CI 1.21,1.43), with fetal death OR,=,1.19 (95% CI 1.02,1.39) and with premature birth OR,=,1.25 (95% CI 1.19,1.31). The univariate stratified analyses suggested effect modification of all observed associations by maternal alcohol consumption. Conclusions This study found associations between outdoor exposure to modeled average airborne POM and several adverse pregnancy outcomes. The data and methods utilized in this pilot study may be useful for identifying hazardous air pollutants requiring in-depth investigation. Am. J. Ind. Med. 40:255,262, 2001. © 2001 Wiley-Liss, Inc. [source] | |||||||||||||