School of Petroleum Engineering,China University of Petroleum (Beijing)Research Institute of Exploration andDevelopment,PetroChina Huabei Qilfield Company No.4 Drilling Engineering Branch,Bohai Drilling Engineering Company Limited,China National Petroleum Corporation Coalbed Methane Exploration and Development Division,PetroChina Huabei Oilfield Company

为解决马壁区块煤层气钻井漏失、井壁失稳和气侵等成井难题,通过室内对比试验,测定了注3种不同钻井液的煤岩单轴抗压强度,及其封堵煤岩后其承受液压力的大小。试验研究结果表明:注氯化钾溶液、低固相聚合物钻井液可使煤岩强度分别降低19.2%、11.5%,注绒囊钻井流体则能提高38.4%,并且注绒囊钻井流体封堵煤岩后承受液压力达20 MPa以上,注氯化钾溶液和低固相聚合物钻井液,其液压力分别为1.61、8.04 MPa,证明绒囊钻井流体防塌防漏能力强。现场应用结果与室内试验结果一致,煤层气绒囊钻井液满足稳定井壁和防漏堵漏要求,结合增加维护次数、减少单次维护数量的施工工艺,解决了马壁区块煤层气钻井难题。

in order to solve the leakage of the coalbed methane driing, el al unstability,gas cutting and oter well completion difiulis in Mabi Block with an ndoor contrast experiment,the coal rock uniaxial compressive strength injected with thveed lling liquids and the licud pressure size of the cal nd rock sealed were measured.The experiment study results showed that with the injection of the potassium chloride sotution.the cal and rck srength was reduvced by 19.2%.ith th itj cton of the solid phrase polymerthe rilin licuid was reduced by 115%.with the inectio of the fuzz a . he drlig liuid could e inceased by 38.4%.with the ine cton of the fuzzy al riling licuid,the liquid pressure of the coal and rock sealed would be over 2』 4Pa.with the inj cion ofthe potassum chloride soutien and low sold phrase polymer drling liouid .the licuid pressure would only be 1.51 and 8 04 MIPa indidull:The fuzzy ball rilin liquid showed a highcolapse prevenion and leakage preventon capacity.The site application resuts were all same and the fuzz)ball iling liquid ofthe calbted methane coud met the repurement ofthe stabe wel wall nd the leakage prevention and leakage sealed.Theconstruction technicue with the naintenance umiber increased and the each maintenance volume reduced applied could solve the difficulties of the coalbed methane drilling in Mabi Block.

国家科技重大专项资助项目(2016ZX05064002)；