Gas loss calculation method for gas content determination by sampling method based on negative pressure pneumatic conveying

In order to determine the gas loss quality during coal sampling based on negative pressure pneumatic conveying, the gas desorption law of coal particle was studied by self-developed gas desorption system of coal particle under negative pressure. The experimental samples, sampled from Xin'an coal mine, were carried out desorption experiment that under negative pressure and atmospheric desorption after negative pressure, respectively. The results show that the gas cumulative desorption quality increases with the negative pressure and desorption time. But it decreases when atmospheric desorption after negative pressure desorption corresponding. The Barrel model is appropriate for gas desorption law under negative pressure in the first two minutes and under atmospheric desorption after negative pressure desorption in the first ten minutes. The error between the prediction results based on the new correlation formula and the actual value is less than 4.83%. © 2017, Editorial Board of Journal of CUMT. All right reserved.