煤层气筛管水平井低产原因分析和治理对策研究——以沁水盆地南部煤层气筛管水平井为例

Study on Causes and Treatment Methods of Low Production of Coalbed Methane Screen Horizontal Well——A Case Study in Southern Qinshui Basin

筛管水平井是煤层气开发过程中较为重要的一种井型,在渗透率高的浅层煤层气开发中取得产量突破。但随着储层地质条件变差、气井生产时间延长,实际生产实践中出现部分低产筛管水平井。本文从地质因素、钻井因素、排采因素、作业因素四个角度对煤层气筛管水平井低产原因进行了讨论。煤储层渗透率低、地层堵塞、井筒堵塞是造成筛管水平井低产的三大原因。针对不同低产原因形成了针对性措施增产改造工艺。各措施增产工艺技术在沁水盆地南部樊庄区块取得较好效果。

The screen horizontal well is a kind of important well type in coalbed methane exploitation,achieving breakthroughs in production in the development of shallow coalbed methane with high permea-bility.However,with the deterioration of reservoir geological conditions and the prolongation of gas well production time,some low-production screen horizontal wells have appeared in production practice.This paper discusses the causes of low production of coalbed methane screen horizontal wells from four factors:geological factor,drlling factor,production factor and operation factor.Low permeability of coal reser-voir,coal reservoir plugging and wellbore plugging are the three main reasons causing the low production in screen horizontal wells.The corresponding measures to increase production are developed for different reasons of low production.The techniques for increasing production have been well applied in Fanzhuang Block in the southern Qinshui Basin.