摘要
The enhanced coalbed methane recovery using CO_(2) injection(CO_(2)-ECBM)is widely proposed as a way of achieving the energy transition and reducing atmospheric CO_(2),in areas such as the Lorrain basin in France,where heavy industry is responsible for huge CO_(2) emissions and coal mines have been closed for more than a decade.This paper deals with the feasibility of extracting methane from the Lorraine basin using CO_(2)-ECBM by comparing data from sorption isotherms,thermogravimetric analyses and breakthrough curves for two coal samples.One is bituminous(Box 18),from Folschviller(France)and is compared with another sub-bituminous(THO1)from La Houve(France),which is used as a reference because it was identified as a good candidate for CO_(2)-ECBM in a previous research program.The quantities of adsorbed gases(CO_(2)/CH_(4))obtained by sorption isotherms,thermogravimetry and CO,breakthrough curves showed that Box 18 adsorbs more CO_(2) and CH_(4) than THO1 due to its higher porosity and good affinity for gases(CO_(2)/CH_(4)).Toth model fits the experimental CH_(4) and CO_(2) adsorption isotherms better,reflecting the fact that the adsorption surface of the coals studied is heterogeneous.Adsorption enthalpies obtained by calorimetry indicated physisorption for gas-coal interactions,with higher values for CO_(2) than for CH_(4).Thermogravimetric analyses and breakthrough curves carried out at up to 50%relative humidity showed that the adsorption capacity of CO_(2) decreases with increasing temperature and the presence of water,respectively.The compilation of these experimental data explained the adsorption process of the studied coals and revealed their advantages for CO_(2)-ECBM.
基金
financed by the REGALOR project(Ressources Gazieres de Lorraine).
