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J.C. Quick

Publications and source records attributed to J.C. Quick.

3 recordsLinked to original sources

Carbon dioxide emission factors for U.S. coal by origin and destination

This paper describes a method that uses published data to calculate locally robust CO 2 emission factors for U.S. coal. The method is demonstrated by calculating CO 2 emission factors by coal origin (223 counties, in 1999) and destination (479 power plants, in 2005). Locally robust CO 2 emission factors should improve the accuracy and verification of greenhouse gas emission measurements from individual coal-fired power plants. Based largely on the county origin, average emission factors for U.S. lignite, subbituminous, bituminous, and anthracite coal produced during 1999 were 92.97,91.97,88.20, and 98.91 kg CO 2 /GJ gross , respectively. However, greater variation is observed within these rank classes than between them, which limits the reliability of CO 2 emission factors specified by coal rank. Emission factors calculated by destination (power plant) showed greater variation than those listed in the Emissions & Generation Resource Integrated Database (eGRID), which exhibit an unlikely uniformity that is inconsistent with the natural variation of CO 2 emission factors for U.S. coal. ?? 2010 American Chemical Society.

Environmental Science & Technology

Mercury content of the Springfield coal, Indiana and Kentucky

With pending regulation of mercury emissions in United States power plants, its control at every step of the combustion process is important. An understanding of the amount of mercury in coal at the mine is the first step in this process. The Springfield coal (Middle Pennsylvanian) is one of the most important coal resources in the Illinois Basin. In Indiana and western Kentucky, Hg contents range from 0.02 to 0.55 ppm. The variation within small areas is comparable to the variation on a basin basis. Considerable variation also exists within the coal column, ranging from 0.04 to 0.224 ppm at one Kentucky site. Larger variations likely exist, since that site does not represent the highest whole-seam Hg nor was the collection of samples done with optimization of trace element variations in mind. Estimates of Hg capture by currently installed pollution control equipment range from 9-53% capture by cold-side electrostatic precipitators (ESP) and 47-81% Hg capture for ESP + flue-gas desulfurization (FGD). The high Cl content of many Illinois basin coals and the installation of Selective Catalytic Reduction of NOx enhances the oxidation of Hg species, improving the ability of ESPs and FGDs to capture Hg. ?? 2005 Elsevier B.V. All rights reserved.

International Journal of Coal Geology

Mercury in US coal: Observations using the COALQUAL and ICR data

The COALQUAL data set lists the mercury content of samples collected from the in-ground US coal resource, whereas the ICR data set lists the mercury content of samples collected from coal shipments delivered to US electric utilities. After selection and adjustment of records, the COALQUAL data average 0.17 ??g Hg/g dry coal or 5.8 kg Hg/PJ, whereas the ICR data average 0.10 ??g Hg/g dry coal or 3.5 kg Hg/PJ. Because sample frequency does not correspond to the inground or produced tonnage, these values are not accurate estimates of the mercury content of either in-ground or delivered US coal. Commercial US coal contains less mercury than previously estimated, and its mercury content has declined during the 1990s. Selective mining and more extensive coal washing may accelerate the current trend towards lower mercury content in coal burned at US electric utilities.

Conference Paper