Drainage technology and test of stratified pressure control with four-channels of CBM well in double coal seams

Aiming at the problems of mutual interference between layers and serious damage in reservoirs in the production process of double-coal CBM wells, a four-channel stratified pressure control drainage technology was proposed, in the process of drainage, two coal seams were controlled in different pressure systems to achieve the purpose of stratified production and CBM well drainage device with four-channel packer, monitoring equipment, multi-channel tubing centralizer, roller sucker rod centralizer and auxiliary communication tube for double coal seams was developed. Field application test shows that the four-channel packer can achieve the isolation effect according to the needs, so that the two production layers are in two different pressure systems, and the four-channel layered pressure-controlled drainage technology has practical feasibility.