In order to avoid wasting resources, environmental pollution and prevent gas explosion in mine, purifying methane from low concentration coal bed methane by hydrate formation has been studied. For increasing the hydrate formation rate and methane recovery, 5.8 mol% tetrahydrofuran （ THF ） -300 ppm sodium dodecyl sulfate（SDS）solution were introduced. The key factors that influenced the gas consumption, reaction rate, methane concentration in the hydrate, methane recovery and separation factor were investigated. Experimental results indicated that the higher pressure, lower temperature, longer reaction time facilitated gas consumption, methane recovery and separation factor. The temperature was the key factor affecting the methane separation factor, and the increase of temperature is propitious to the improve selectivity of methane hydrate. Since the hydrate separation technology can substantially avoid the explosion problem caused by methane and on the basis of the results obtained in this work, we may say that this technology is quite suitable for the separation of coal bed methane mixed with air and has broad prospects for industrial applications.
Keywords hydrate, low concentration coal bed methane, methane, separate, tetrahydrofuran, sodium dodecyl sulfat