Methodology for the Determination of Gas Phase Effluent Rates in Coal Gasification Systems

摘要

Carnegie-Mellon University environmental assessment has been coordinating activities in the Department of Energy's high Btu coal gasification program. Since the linkage between effluent production rates and gasifier operating conditions is considered crucial, a great deal of work is being done in the area. Most current methods monitor only pilot plant wastewater streams to back-calculate the gasifier effluent production. However, these methods possess some inherent deficiencies and cannot always provide a true measure of effluent production rates. To bypass these problems, a gas phase sampler was built to measure production rates at the gasifier outlet. Shakedown tests at the CO sub 2 -Acceptor and HYGAS pilot plants were necessary to correct design deficiencies, but the final system works well and collects the necessary components from the sample gas to give accurate results. However, sampler-related problems were severe enough to make this report more of a scoping study than the originally intended presentation of gasifier production correlations. The sampler's dependence on process data and sample analyses causes the final results to be only as good as these data. Cyanide and thiocyanate sampling was hindered by rapid sample degradation which biassed the data. Difficulties with organics sampling peculiar to the HYGAS system were encountered due mainly to its complex effluent production patterns. Recommendations are given which should correct these problems and allow generation of quantitative results.