针对沁水盆地南部煤层气井储层压力低、易漏失、易坍塌的特点，开发了超低密度泡沫水泥浆体系及暂堵型前置液体系，并形成了泡沫水泥浆固井技术。泡沫水泥浆体系密度为1.10~1.20 g/cm3，具有良好的流动性能、无游离液、沉降稳定性好、API失水量小于50 mL/30 min、稠化时间合理、水泥石强度高等优点；暂堵型前置液体系具有良好的流变性能，对3号煤层具有良好的堵漏能力。根据钻井过程中出现的漏失情况、完钻后的钻井液返出情况及井壁稳定情况，从固井浆体的用量、顶替液的顶替排量等方面总结了泡沫水泥浆固井的配套工艺措施。在沁水盆地南部现场试验了4口井，取得了较好的效果。%Aimed at the characteristics of CBM wells in south part of Qinshui basin, such as low pressure, easy leakage and easy collapse, high performance foam cement(HPFC) system of ultralow density and temporary plugging prepad fluid system were developed and cementing technology with foam cement slurry for coalbed methane well was formed. The density of HPFC system is 1.10~1.20 g/cm3, it has many advantages, such as good flowing properties, no free liquid, stable sedimentation, small API filtration loss (≤50 mL/30 min), reasonable thickening time and high strength of set cement. The temporary plugging fluid system has good rheological proper-ties, good leaking stoppage capacity for seam.3. The paper summarizes technological matching measures of foam slurry cementing techniques from the amount of cementing slurry and displacement fluid on the basis of the leakage situation, returning situation of drilling fluid and hole wall stabilization condition. This cementing technology has been applied in 4 wells for field test at the southern Qinshui basin, and good effect is obtained.
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