PFL系列超高温聚合物降滤失剂在徐闻X3井的应用

PFL系列聚合物降滤失剂具有黏度低、耐温抗盐降滤失效果显著等特点。质量分数为1%的PFL-L、PFL-H水溶液的表观黏度分别为12 mPa.s和26 mPa.s。在240℃滚动老化16 h情况下,加有5%PFL-L的盐水泥浆(4%膨润土浆+36%NaCl)的滤失量由226 mL(空白样)降至32 mL;加有4%PFL-H的盐水泥浆的滤失量由226mL(空白样)降至8.2 mL;加有1.5%PFL-H的淡水泥浆(4%膨润土浆)的滤失量为由100 mL(空白样)降为9.6 mL。以PFL系列超高温聚合物降滤失剂为主,结合磺化类降滤失剂、抑制剂、防塌剂、稀释剂,形成了抗200℃强抑制盐水及淡水钻井液体系。现场应用表明,PFL系列超高温聚合物降滤失剂抗高温能力强,降滤失效果显著,确保井深5974 m、电测温度为211℃的徐闻X3井顺利钻至井深6010 m。表5参4

Application of PFL Series Ultra-High Temperature Polymer Filtrate Reducer in Xuwen X3 Well

PFL series polymer filtrate reducer is characterized of low viscosity,good capacities of depressing the filter loss,heat resistance and salt tolerance.The apparent viscosity of 1% PFL-L aqueous solution and 1% PFL-H aqueous solution were 12 mPa · s and 26 mPa · s,respectively.After aging at 240℃/16 h,with the addition of 5%PFL-L,the filer loss(FL) of the saturated salt water mud(SSWM),composed of 4% bentonite and 36% NaCl,decreased from 226 mL(blank group) to 32 mL;with the addition of 4%PFL-H,the FL of the SSWM decreased from 226 mL(blank group)to 8.2 mL;with the addition of 1.5% PFL-H,the FL of fresh water mud,composed of 4% bentonite,decreased from 100 mL(blank goup)to 9.6 mL.Based on the PFL series ultra-high temperature polymer filtrate reducer and the optimized sulfonating filtrate reducer,inhibitor,lubricant,thinner,the strong inhibited brine and fresh drilling fluids,which were heat resistant to 200℃,were formed.The field application manifested that the PFL series ultra-high temperature polymer filtrate reducer showed strong heat resistance and good capacities of depressing the filter loss,making sure that the Xuwen X3 well was drilled to 6010 m and the logging temperature of 211℃ at the depth 5974 m.