Strategic value and choice on construction of large CMG industry in China

China is very rich in coal measure gas (CMG) resources. Although the CMG industry has been developed for more than 30 years,the production from surface wells only accounts for 3.07% of the total national natural gas production in 2020,which scale is not satisfactory. To overcome the dilemma,the Chinese Academy of Engineering organized a strategic discussion on the effective CGM development for building a large industry. The authors in this paper look at a broader field,consider other types of natural gas in coal measures,demonstrate the strategic value and possibility of building a large CMG industry in China,deliberate the current difficulties and challenges,and put forward some suggestions on the choice of technical strategy and the improvement of guarantee conditions to overcome the dilemma. By analogy with the development process of coalbed methane (CBM) industry in the United States,it is considered that the formation of a large CMG industry is marked by two aspects,i.e.,the annual production of more than 30 billion cubic meters and the contribution of more than 4.5% to the total annual production of natural gas in China. The development of a large CMG industry has three strategic values. Firstly,the large industry is one of the cornerstones of national natural gas security. Secondly,the effective CMG development will continue to help the healthy development of China’s main energy industry. Thirdly,the large scale development and utilization of CMG will help the favorable realization of the national “double carbon”goal. China has a feasible foundation for building a large CMG industry,including a strong national demand,a great potential in CMG resources,implemented solid industrial layout and broad scientific and technological basis. China still faces five difficulties and challenges in realizing an effective CMG development and then building a large industry,i.e.,losing patience in the industry,the single well production that has still not been doubled overall,the insufficient attention to the utilization rate of proved CBM reserves,the insufficient efforts to explore new fields and new directions,and the separately set mining rights for different types of CMG. The analysis shows that the development of applicable technology is the only way to extract CMG resources under different geological conditions in China with high efficiency and low cost,and the mechanism innovation is the guarantee basis for the rapid development of the industry. It is suggested to continuously tackle key technologies in five aspects,including the low-cost and efficient gas extraction in underground coal mines,the reserves and production enhancement of CBM wells in old areas,the evaluation and development of high quality deep CMG reservoirs,the exploration and orderly development of thin interbedded CMG resources,and the UCG (underground coal gasification)CMG combined mining. It is considered that the key to the construction of guarantee conditions lies in two aspects:firstly,continuously implements the national major scientific and technological plan of CMG to promote the formation of the large industry as soon as possible;secondly,tries the integration of CMG mining rights to stimulate the maximum release of CMG resources potential. The relevant understandings and suggestions in this paper may provide reference for strategy formulation and scientific and technological research in the industry.