Study On The Measurement Method Of Coal Seam Primitive Gas Content And The Influencing Factors Of Its Errors

This paper,based on the data which was gotten from mine and laboratory test,studies systematically on the direct measurement method and the indirect measurement method of coal seam primitive gas content and the factors which caused the measurement errors. The research results show the following:For the direct measurement method whose coal samples are gotten from the porthole, the errors of computing the coal samples'exposing time causes the errors of gas lost quantity calculation being between 12.64% and 15.38% and the errors of the coal seam primitive gas content calculation being between 0.67% and 4.48%.For the indirect measurement method,to reduce the errors efficiently,the isothermal absorption test should be done in the following conditions:the particle size range is between 0.17 mm and 0.25 mm,the temperate is the coal seam's actual temperature,the most pressure is 7 MPa, the adsorption equilibrium time is 7 hours. According to the study on the measurement methods of coal seam primitive gas content and the influencing factors of its errors,the paper puts forward how to reduce errors during measuring the coal seam primitive gas content in mine.