The 4th International Symposium on Mine Safety Science and Engineering (ISMSSE2018)

395 / 2018-10-09 08:45:32

Dissociation kinetics of mine gas hydrate induced by heating above the freezing point

gas hydrate; dissociation kinetics; dissociation rate; gas component

Gas of Coal Mine & Coal and Gas Outburst > Gas of Coal mine

This study evaluated the effect of temperature on the stability of mine gas hydrate during storage and transportation. The hydrate dissociation experiment was conducted by using visual hydrate formation and dissociation experimental device for two gas samples under four different temperature (284.15, 286.15, 288.15, and 290.15 K). Based on the experimental data, it was found that the pressure curve during gas hydrate dissociation is mainly composed of rapid dissociation, slow dissociation, and stable stages. Temperature has a significant effect on the average dissociation rate for the gas system, where a higher temperature is related to greater average dissociation rate. The maximum average dissociation rate was determined to be 4.34∙10-3 mol/min (system I-4). According to gas chromatography analysis, CH4 concentration in the gas phase generally increased during the hydrate dissociation process, which was 78.97~91.16% and 65.37~85.12% in System I and System II, respectively.