煤层气井储层钻井液损害及保护工艺技术

CBM Well Reservoir Drilling Fluid Damage and Protection Technology

在煤层气井开发过程中,钻井完井液滤液和固相在完井作业过程中的液柱压差、完井液对储层的浸泡时间、环空流速、井下复杂情况等作用下侵入地层,发生物理化学反应,堵塞气流通道,降低渗透率,对煤储层造成不同程度的损害。在分析煤储层的损害的机理及原因的基础上,提出了从合理选配钻井液、使用暂堵剂、选择合理的钻井工艺等方面对煤储层进行保护的技术措施。

During the CBM well exploitation process, in virtue of fluid column pressure difference of well completion fluid filtrate and solidoid during well completion operation process, reservoir well completion fluid soaking time, annular space velocity and underground complication bring about physical and chemical reactions, block up gas channel, lower down permeability and damage coal reservoir to varying degrees. Based on coal reservoir damage mechanism and causation, have put forward coal reservoir protection technological measures of rationally selective proportioning of drilling fluid, temporary blocking agent using, rational drilling technology etc.