Current situation and development trend of coalbed methane development and utilization technology in coal mine area

Since the 12th Five Year Plan,the development and utilization technology of coalbed methane in China’ s coal mining areas has made great progress. Although the number of coal mines in China from nearly 20 000 to less than 5 800,the production of coalbed methane has increased from 8. 8 billion m3 in 2010 to 18. 4 billion m3 in 2018,the u- tilization rate has also increased by 10 percentage,and the technology has made a great contribution to the coalbed methane industry. However,there are also new problems such as low single well production and high gas source disper- sion. Therefore,this paper comprehensively reviews the scientific and technological innovation and application effect of surface extraction technology and equipment,underground extraction technology and equipment,and high and low con- centration coalbed methane utilization technology and equipment in coal mine areas in recent 10 years. This paper ex- pounds the development and utilization of coalbed methane in the coal mine areas,including three-level gas geological analysis technology,roof fracturing technology of ground wells in broken soft and low-permeability coal seams,layered and pressure controlled combined mining technology of coal seams,L-shaped Roof Horizontal Well Technology in min- ing area,kilometer long Directional Borehole technology under the well,underground hole protection drilling technology of broken soft coal seam,remote control drilling technology of intelligent drilling machine,technology of hydraulic frac- turing / slotting and permeability increasing in well water and so on,and the latest progress and technical indicators of utilization equipment for coalbed methane,such as cryogenic liquefaction of medium and high concentration coalbed methane,classified compression and concentration of low concentration coalbed methane,thermal storage and oxidation utilization of ultra-low concentration coalbed methane,etc. On this basis,according to the characteristics of deep min- ing,western mining and high-intensity intensive mining,the paper classifies the technical bottlenecks and development trends that restrict the development of coalbed methane industry,and puts forward the development ideas of collabora- tive planning and joint development of coal mining and coalbed methane development.