新疆阜康白杨河示范工程煤层气井负压抽采应用试验

Application Test of Negative Pressure Pumping of Coalbed MethaneWells in Fukang Baiyanghe Demonstration Project

阜康白杨河示范工程经过多年排采生产,部分煤层气井产气量不可避免的出现下滑态势。分析认为,随着煤层气的大量解吸,套压会逐步降低,当套压接近下限压力,即集输管线压力(一般0.2MPa),就不再正常解吸产气。为了提高这类煤层气井的采收率,优选了三口不同埋深的煤层气井进行负压抽采试验。结果表明:通过负压抽采可以有效增大井内与储层压差,有利于促进煤层气解吸和运移,可以实现增产。文章详细介绍了负压抽采的原理、排采原则及试验流程,可以为煤层气低产井增产提供借鉴。

After years of drainage and production,Fukang Baiyanghe Demonstration Project has inevitably seen a decline in gas production from some coalbed methane wells.Analysis suggests that as a large amount of coalbed methane is desorbed,the casing pressure will gradually decrease.When the casing pressure approaches the lower limit pressure,that is,the gathering and transportation pipeline pressure(usually 0.2MPa),gas production will no longer be desorbed normally.To improve the recovery rate of such coalbed methane wells,three coalbed methane wells with different burial depths are selected for negative pressure pumping tests.The results indicate that negative pressure extraction can effectively increase the pressure difference between the well and the reservoir,promote the desorption and migration of coalbed methane,and achieve increased production.This article provides a detailed introduction to the mechanism,drainage principles,and experimental process of negative pressure pumping,which can provide a reference for increasing production in low-production wells of coalbed methane.