高、低煤阶CO_2与CH_4竞争吸附解吸置换效果分析

Reasearch on CO_2,CH_4 Competitive Adsorption,Desorption and Replacement Effect of High and Low Rank Coal

基于山西沁水盆地柿庄北煤层气勘探开发资料以及新疆硫磺沟煤矿地质资料,采用U.S.A TerraTek IS-100等温吸附解吸仪开展了CH_4、CO_2单组分吸附解吸试验以及CO_2、CH_4混合气体竞争吸附解吸试验研究,分析了高、低煤阶煤对CH_4、CO_2单组分气体吸附解吸规律以及CO_2、CH_4混合气体竞争吸附解吸特性。结果表明:山西沁水高煤阶煤样吸附能力强于新疆硫磺沟低煤阶煤样,高煤阶煤样对CH_4、CO_2气体的吸附解吸曲线具有可逆性,低煤阶煤样对CO_2气体的解吸曲线具有明显的滞后现象;混合气体竞争吸附解吸过程中,高煤阶煤样中CO_2、CH_4吸附浓度及吸附量变化较大,高煤阶煤样CH_4对CO_2的分离因子强于低煤阶煤,高煤阶煤样竞争解吸效果明显,因此高煤阶煤更利于CO_2置换CH_4,且低压置换效果更好;低煤阶煤样中CO_2、CH_4吸附浓度及吸附量变化不大,竞争吸附解吸效果不明显,置换效果较差,说明高煤阶煤更适合通过注CO_2置换CH_4来提高煤层气的采收率。

Based on the information of North Shanxi Qinshui basin coalbed methane exploration and development and Xinjiang Liuhuanggou coal mine geological data, the research used U. S. A TerraTek IS 100 isothermal adsorption and desorption instrument to carry on the experiments of the single CH4, COx component adsorption and desorption and COx, CH4 competitive adsorption and desorption, analyzed of the high and low rank coal on CH4 , COx single component gas adsorption desorption and characteristics of COx, CH4 competitive adsorption and desorption. The results showed that： the Shanxi Qinshui high rank coal adsorption capacity was stronger than Xinjiang Liuhuanggou low coal rank, the adsorption and desorption curves in Shanxi Qinshui Coal of the CH~, COx gas were reversible, the desorption curve of Xinjiang Liuhuanggou low rank coal sample of COx gas has obviously lags. The COx , CH~ corn petitive adsorption and adsorption concentration changed in Shanxi Qinshui high rank coal were larger, the high rank coal separation factor of CH2 to COx is stronger than that of low rank coal, therefor, the replacement effect was ob vious and was better in the low pressure area. The Xinjiang Liuhuanggou low rank coal samples changed less and the replacement effect was not obvious, these indicated that the high rank coal is more suitable to improve the production by COx replacement CH4.