Application of molecular simulation in coalbed methane reservoirs: A systematic review

As an important strategic supplementary energy of conventional natural gas, coalbed methane (CBM) has become a hot topic in energy exploration at home and abroad due to its advantages of high efficiency, cleanness and wide distribution. Thanks to the rapid development of computer technology and the continuous optimization of dynamics simulation software, the study on micro-mechanism of gas enrichment and migration by applying molecular simulation technology has become the important research field. In this review, we summarized various types of pore models of coals including organic matter pore, mineral pore and composite pore systems. The development of the micro-configurations in structure and composition was reviewed. Meanwhile, the micro-evaluation indexes of fluid properties in reservoir were also listed systematically. In a word, the application of the molecular simulation technology in CBM reservoir is far from mature. Through the summary of the current research, we discussed the existing problems in this field and the future development direction.