Comparative Analysis on Determining Coalbed Gas Content With Two Different Coal Sampling Methods

It was vital important to determine coalbed gas content quickly and accurately for guiding the work of preventing outburst in high gas and gas outburst coal mines. By using the coring tube sampling and the pressure air orifice slagging sampling method, the gas content comparative determining tests were carried out in 34_xia6 and 34_xia5 floor roadway in Qinan Coal Mine. The results showed that, compared with orifice slagging sampling, the coal sample exposure time was longer, and the coal sample size was bigger for the coring tube sampling method. The exposure time and coal sample size had great impact on calculating losing gas content and determining gas content. The gas content value by coring tube sampling was bigger, in similar sampling determination circumstances, from the safety aspect, the coring tube sampling method should be adopted to determine 3₂ coalbed gas content in Qinan Coal Mine.