Abstract: in order to verify the licuefaction natural gas(LNG) technoiogy feas tilitywith low concentration coalbed methane concentration,a LNG pilot device witha preparation ofthe low concentration c lbed methane cryogeni licueaction was established.Afround the saety and energy consumption problems of the device in the operation process , experiment study on th licuefacion technique parameters was conducted to povide references o the enlarged design and saety operatio of he liouefaction device.The device operation and the related explosion experiment condtion showed that L NG made from the cryogent liuefacion of the low concentraton coalbed methane was feasible in technology.The recovery rate of the methane woud be surged and senstive by the gas soure condtion and the product purty would not be highly surged.The temperature of the distilation tower would have high influences to the netane recovry rate and theproduct purity and in he operatonaccoding to the ravw gas methane content variation.av gas fow varation and cold quantty siricient or not and ther facors adjustments shoud be conduced. Afer thetechnology promoted,the utiliation problems of the low concentraton coalbed methane when the methane volune fracion higher than 25%.could be efectively solved.Thus,on certain degree,the insufficient natural gas supply status in China could be released.