高含酸性气碳酸盐岩气藏流体敏感性实验研究  

Experimental Research on Fluid Sensitivity of Carbonate Gas Reservoirs with High Content of Acidic Gas

作　　者：刘大伟[1] 康毅力[1] 李前贵[1] 雷鸣[1] 疏壮志[2] 

机构地区：[1]油气藏地质及开发工程国家重点实验室(西南石油大学),四川成都610500 [2]中国石化南方勘探开发分公司,云南昆明650000

出　　处：《油田化学》2007年第3期193-196,201,共5页Oilfield Chemistry

基　　金：四川省杰出青年学科带头人培养基金项目(项目编号07ZQ026-11302ZQ026-042);中国石油天然气股份有限公司科技风险创新研究项目

摘　　要：对川东北雷口坡组、嘉陵江组、飞仙关组、长兴组高含H，S及032的碳酸盐岩储层流体敏感性进行了实验研究，结果表明岩样速敏损害弱～强，水敏和盐敏损害中偏弱～极强，碱敏损害严重。岩石学分析揭示，川东北高含酸性气碳酸盐岩储层发育伊利石、微晶石英、白云石、方解石、硫化钙等潜在损害物质。钻井完井液侵入会破坏储层各物质间的原始动态平衡，诱发储层损害。主要损害机理为：①储层流体pH增加引起黏土矿物以及微晶石英失稳；②碱液与微晶石英、长石、白云石反应生成硅酸盐、高岭石、水镁石等新矿相；③流体矿化度改变可降低伊利石微粒间的连接力；④硫化钙水解产生OH^-，过量的OH-与Ca^2＋结合形成氢氧化钙沉淀；⑤储层含水饱和度和流体离子浓度改变，致使焦沥青脱附并在储层深部沉积；⑥硬石膏水化膨胀、分散运移。针对该气藏损害机理，可采用屏蔽暂堵技术以形成优质滤饼，有效降低储层流体敏感性损害。图5表2参10。The fluid sensitivities of the carbonate gas reservoirs with high content of acidic gas, hydrogen sulfide and carbon dioxide, in Leikoupo, Jialingjiang, Feixianguan, and Changxing Formations in Northeast Sichuan Basin are investigated experimentally. The experimental results show that the velocity sensitivity of the gas reservoirs is weak to strong, the water and the salinity sensitivities- middle minus to very strong and the alkali sensitivily-extremely strong. The pertological analyses indicate that there exist massive potentially damaging minerals such as illite, microcrystalline （MC） quartz, dolomite, calcite, and calcium sulfide in the gas reservoirs. Drilling-in fluids invaded can disturb the dynamic balance among the original reservoir materials and cause the reservoir formation to be demaged. The main mechanisms involved in formation damage are summerized as follows：① destabilization of MC quartz and clay minerals owing to increased pH values of the formation fluids;②creation of more demaging new mineral facies such as silicates, kaolinite, hydrophyllite, and others in reaction of alkali lye with MC quartz, feldspar, and dolomite;③reduction in binding forces between illite particles owing to changes in formation fluid salinity; ④hydrolysis of calcium sulfide to give massive OH^-, combination of excessive OH^- with Ca^2＋ and precipitation of Ca（OH）2 thus formed; ⑤desorption and redeposition in farther zones of pyrobitumen owing to changes in zonal water sturation and foramation fluid salinity; ⑥ hydration, dispersion and migration of anhydrite. Based on the formation demaging mechanisms, it is suggested that the reservoir formation damage in the carbonate gas reservoirs sensitive to formation fluids can be well controlled through creation of high quality filter cake by a temporarily shielding drillingin fluid.

关 键 词：碳酸盐岩气藏 储层损害 储层敏感性 酸性气 敏感性矿物 流体 钻井完井 

分 类 号：TE258.3[石油与天然气工程—油气井工程] TE258.1