FINE MANAGEMENT PRACTICE OF COALBED METHANE GROUND EXTRACTION ON XIANDAO-1 WELL IN SHIYUAN COAL MINE
Fine extraction is a practice in coalbed methane management by using extraction data for obtaining a high yield.When extracting coalbed methane on ground,mining coal leads to a decrease in strata energy,and a fast falling in case pressure,which needs fine extraction to secure ground extraction for a stable production.This paper,based on a case study on Xiandao-1 well in Shiquan coal mine,studies its structure,buried depth and strata pressure,and compares its geology with surrounding basin of coalbed methane,analyzes its fracturing features and conducts fine extraction management,providing references for later mass ground extraction.Five steps are planned,setting up objective of daily production up to 400 cubic meters over 30 days,understanding its occurrence and under-pressured features,conducting extraction gas-water evolution characters,planning"balanced water production stage(no gas release),controlling well bottom fluid pressure stage,stably increasing production stage,and declining stage",controlling well bottom pressure to balance strata pressure and then to determine critical releasing pressure and water point,releasing point,gas releasing point and stably producing point.Emergency measures are also prepared through three groups in managing the process,site group,research group and decision group.A real-time response and linked decision-making strategy bring a daily gas production from 100,200,400,600 and up to 1 041 cubic meters in two months.Fine extraction management is the key means for such an achievement.Mass ground gas extraction requires planning,emergency measures and flowchart,which are vital technical guarantees to ensure a good production.
万方数据
维普
