Development of an Extractive Continuous Monitor For Hydrogen Chloride (Hc1) Analyses of Coal-Derived Process Streams

Abstract

Abstract An HC1 monitor has been developed at the Morgantown Energy Technology Center (METC) for the extractive analysis of hightemperature/high-pressure, coal-derived process streams. This monitor is capable of HC1 concentration measurement in the presence of all known coal gasification products. Detection is based on the ability of HC1 to protonate a high boiling alcohol (solvent) and, thus, enhance the conductivity of the alcohol. Conductivity is then related to HC1 concentration. the observed high degree of sensitivity that can be achieved is a result of analyte preconcentration prior to the conductivity measurement due to the apparently fast dissolution rate of HC1 into the alcohol solvent coupled with a large analyte gas-to-solvent ratio. the linear dynamic range of the HC1 monitor is two orders of magnitude. However, since the degree of preconcentration can be adjusted by changing either the solvent or analyte gas flow rate, the HC1 monitor has an extended operating range of six orders of magnitude (ppb lower limit, percentage upper limit). the practical lower detection limit for the HC1 monitor is estimated to be 50 ppbv. Precision is good with typical relative average deviations of about three parts per hundred. Although the HC1 monitoring method was originally designed for the analysis of gasification process streams, the system can be adapted for use with a variety of process gas streams.