Results of comparative sorption studies of the coal-methane system carried out by means of an original volumetric device and a reference gravimetric instrument

Abstract

The present paper discusses the idea of an innovative device for sorption measurements, working under isobaric conditions and based on a precise piston pressure regulator. As part of the research, the author compared the results of sorption measurements obtained with the constructed piston sorptomat with the results obtained by means of a reference device. The sorption capacities of 15 granular high-volatile bituminous coal samples, determined on the basis of methane sorption courses registered with both instruments were compared. The author also defined the criterion of compatibility of the obtained results, which stated that the compared results are compatible if their values fall within the range of measurement uncertainties of the instruments with which they had been established. After comparing the results obtained with the original instrument with the results obtained with the reference gravimetric device, it was observed that 30 out of 33 measurements of sorption capacities were classified as compatible (based on the defined measurement compatibility criterion). The mean difference in the readings provided by both instruments was 1.64%, for sorption capacity determined in 33 measurement points and the methane pressure range of 1–10 bar.