97/03251 Characterization of trace element emissions from a pilot-scale coal combustion unit

Abstract

The flue gas cleanup projects in the in-house research program at the Pittsburgh Energy Technology Center range from laboratory-scale work to testing with the combustion products of coal at a scale equivalent to about 0.75 MW of electric power generation. The largest unit is a 500-pound-per-hour coal combustor, complete with ductwork, spray dryer, baghouse, and ancillary equipment. Over the past year, tests to investigate the distribution and fate of trace elements have been conducted with this pilot unit. These investigations are an integral component of the Air Toxics and Fine Particulate Control subprogrammatic area of the AR and ET Power Systems Program. The overall effort of this area focuses on the improvement of existing technologies and the development of new technologies for the control of hazardous air pollutants and fine particulates associated with coal combustion. A major endeavor within the subprogram is the characterization of trace elements in flue gas from coal combustion, including a special emphasis on mercury speciation. The study described in this paper examined the results from an investigation on the pilot unit; the distribution of trace elements in the ash streams and flue gas stream, material recoveries for the system, baghouse removal efficiencies, and enrichment ofmore » ash particulate. Also, a preliminary comparison between the results from the pilot unit and a full-scale utility that burned coal from the same coal batch is provided.« less