气井关井压产后产量异常下降原因分析.pdf

气井关井压产后产量异常下降原因分析
刘亚林李相方刘广天孙凡晓
(中国石油大学石油天然气工程学院,北京 102249)
摘要:本文论述了关井后井筒压力的恢复原理,分析并描述了无积液气井和积液气井关井过
程中井筒压力和井底流量的变化规律,基于井筒气液分离前后井底压力的理论变化情况,揭
示了积液倒灌产生的原因和条件,通过对倒灌对地层渗透率的影响分析,解释了关井复产造
成产量下降的原因,同时给出了防治倒灌的关井方法。
主题词:气井,关井复产,积液,倒灌
ANALYSIS ON THE ABNORMAL PRODUCTION DRAWDOWN OF GAS WELL REOPENS
LIU Ya_lin, LI Xiang_fang, LIU Guangtian, SUN Fanxiao ( China University of
Petroleum-Beijing,102249, China)
Abstract: In the development of Shengli shallow gas field reservoir, well
shut-in for a period of time is often used to build-up pressure as well as gas
production. But sometimes gas production drops abnormally at the next pressure
build-up. In this article, the pressure build-up principle after shut-in is analyzed.
And the reason influence the production is well loading reverse osmosis which caused
by the added pressure due to dual phase separation in the process of well shut-in.
Key words: gas well, pressure built_up, well loading, reverse osmosis

常规的开采经验认为:地层能量供应不足造成气井产量、压力下降,关井有
助于近井地层能量得到及时补充。当气井生产满足不了经济开采时,采用阶段关
井恢复产量。然而实际生产中,近井地带的污染、井筒积液、井下异常状况等都
会影响气井地面产量和压力。在胜利浅层气藏开发过程中,由于气井产液量很小,
生产中对产水的影响并没有充分考虑。研究表明,胜利小产液气井对气井生产影
响很大,小产液也会带来严重的井筒积液。井筒积液带来的附加压力不仅限制了
气藏产能的正常释放,气井生产时在地面也表现为低压低产,还给储层带来的严
重的污染隐患。尤其对间开型的生产气而言,在关井过程中积液可能倒灌地层,
严重劣化地层渗透率。
1 关井过程中井筒参数变化
分析气井关井过程中产量和压力的变化情况,由于井筒储集效应[1],气井关
井后地面产量立即由q0变为 0,但在一段时间内仍有地层流体流入井筒,压缩井
筒空间使得井底