Study on Desorption Index Sensitivity of Drilling Cuttings from Tunlan Mine

In order to establish and improve the coal and gas outburst prevention technical system of Tunlan Mine, relative sensitivities of dilling cuttings about ga s desorption index K1 and Oh2were determined. Based on high pressure set volume adsorption and desorption experiments and simulation measurement of the drilling cuttings desorption index, the study found that the gas adsorption balance pressure and gas desorption volume of each seam sample from Tunlan Mine was in a power function relationship, and K1 and Oh2was in a liner relationship. The first minute gas desorption volume of each seam sample from Tunlan Mine was more obvious than the fourth and fifth minute by the control function of desorption balance pressure. With the site measured of K1 and Oh2and combined with the minimum mean variance method analysis, the paper hold that the K1 of each seam in Tunlan Mine was more sensitive than Oh2index. Therefore, when predicting the outburst danger was condu cted for each seam in Tunlan Mine, the drilling cuting desorption index K1 should be selected as the main index ( sensitive index) and Oh2should be selected as an aux iliary index.