煤层气井井筒酸洗工艺研究与应用

针对煤层气井在排采过程中产出大量的煤泥导致卡泵、泵漏失、筛管堵塞等井下故障频繁发生，引起修井作业，导致煤层气井排采不连续，储层渗透率降低，产气量下降无法恢复等严重问题，通过煤泥组分分析、酸液配方研究、工艺设计优化形成了解决煤层气井井筒卡堵的酸洗工艺技术。该工艺实现了在不间断正常生产的情况下，通过从油套环空注入酸液，抽油机抽排油管返出的洗井方式，解除井下煤泥堵塞故障，最大限度延长生产时间，减少修井作业。现场应用实践表明，该酸洗工艺技术在煤层气井上应用效果良好，措施有效率达90.5%。

Study and application of acid pickling technology in well bore for coal-bed methane wells

A large amount of coal slime could be produced during CBM wells drainage process,could cause pump leakage,stuck pump or sieve tube blockage,and lead to drainage work interruption,coal seam permeability damage and gas production decrease.In order to deal with this severe problem,the acid pickling technology has been developed based on slime component analysis,acid formula study,and process design to solve the problems like stuck and blockage down in the well bore.To apply this technology,acid fluid is injected into casing tubing annulus and is then discharged through oil tube.By doing so,slime jam could be removed,the duration of production could be maximized,and workover job could be avoided remarkably without interrupting drainage process.Field application shows a good application potential with a 90.5% efficiency,which illustrates a good prospect of application.