高温凝胶化学堵漏技术在XJ-3井封层堵漏作业中的应用

Application of high temperature gel chemical plugging technology in seal plugging operation of XJ-3 well

针对XJ-3井在调层作业中出现的封隔器不能解封而缺乏循环通道,油管内断落连续管导致空间狭窄,地层又漏又喷且有H_2S的复杂情况,设计选用了高温凝胶化学堵漏技术。室内实验表明:高温凝胶抗温达到170℃,成胶强度达到50 000 m Pa·s,且成胶时间可调;在温度160℃,pH值为8或4时,成胶时间在210 min。承压能力测试表明:在井下成胶后堵漏剂能够承受2 MPa/hm的压力,根据XJ-3井井下压力情况确定堵漏剂封堵长度300 m。采用单液法施工,即在地面配好胶液后用一台水泥车将胶液泵入井筒,用钻井泵将胶液顶替到需要的位置;顶替排量控制在400~500 L/min,如现场条件允许,可适当提高顶替排量,施工完成后关井4~6 h完成成胶。施工结果表明高温凝胶堵漏技术有效实现了XJ-3井封层堵漏作业。

In the process of layer adjusting for XJ-3 Well, a series of adverse phenomena appear, such as lack of circulation channel caused by packer can not be unlocked well,the narrow construction space due to the break of continuous tubes,oil leaks and oil gushes from the layers, and H2 S exits in the air flow. Aimed at these questions, high temperature gel chemical plugging technology was used in the design as a seal plugging technology. Laboratory experiments show that,high temperature gel resistance temperature is 170 ,The gel strength reached to 50 000 mPa·s,and the gel time is adjustable. When the temperature of 160 ,pH value is 8 or4,the gel time is in 210 min. Bearing capacity test shows that,after the downhole gel,plugging agent can withstand the pressure of 2 MPa/100 meters. According to the situation of downhole pressure of XJ-3 well, plugging length of 300 meters was designed. Single-fluid method was used in construction,once the slurry is prepared on ground,it was pumped into the mine shaft by using a track,then the slurry can be injected into the needed positions,the quantity of the injected slurry was controlled at the speed of 400 ？500 L/min. If possible,it can improve the quantity of injected slurry. It is needed to close the mine shaft for 4 -6 h to finish the slurry coagulation. Construction results show that,the high temperature gel chemical plugging technology has effectively implemented the seal plugging operations of XJ-3 well.