Influence factor analysis for coalbed methane production in Zhijin Block

Analysis of geological condition, reservoir fracture treatment, matching technology, and drainage system were performed to improve the coalbed methane production in Zhijin Block. The influence factor analysis was also conducted. The results show that the depth of the most productive gas well in Zhijin Block is between 500 and 700 m. The gas production could reach 1 000 m3 when the following criteria are satisfied-using four-stage fracturing,intensity of gravel input between 10 and 15 m3/m, and intensity of liquid input higher than 150 m3/m. A drainage system that is suitable for Jinzhi Block is proposed, which includes four drainage technologies, namely five-segment compression, peak avoidance, area decompression, and regional decompression. This paper provides reference for future coalbed methane exploration in Zhijin Block and in other similar coalbed methane fields as well.