抗硫化氢高强度冻胶阀试验研究  

Experimental Study on High Strength Anti-H_2S Gel Valves

作　　者：李志勇[1] 陈帅[1] 陶冶[2] 马攀[1] 杨超[1] 

机构地区：[1]中国石油大学(北京)石油工程学院,北京102249 [2]中国石油勘探开发研究院,北京100083

出　　处：《石油钻探技术》2016年第2期65-69,共5页Petroleum Drilling Techniques

基　　金：国家科技重大专项"易漏易塌地层钻完井及储层保护技术研究"(编号:2016ZX05044);国家自然科学基金项目"低渗裂缝性砂岩凝析气藏损害机理及有效保护开发一体化新方法研究"(编号:51374225);国家留学基金(编号:CSC No.201506445008);校优秀青年教师基金项目"封堵钻井恶性漏失的新型高强度凝胶研制"(编号:2462015YQ0211)联合资助

摘　　要：在新疆油田实施冻胶阀欠平衡钻井时,地层中富含的硫化氢气体会侵蚀破坏冻胶,影响冻胶阀的性能与使用寿命,针对此问题,开展了抗硫化氢高强度冻胶阀研究。在模拟井温125℃条件下,依次筛选出了主聚合物、有机交联剂、除硫剂三氧化二铁和处理剂,并对其加量进行了优选,配制了冻胶液。对该冻胶液的黏度、冻胶强度、最大可封隔压力及破胶性能等基本性能进行了评价,并利用抗硫化氢评价装置评价了硫化氢对冻胶性能的影响。评价结果显示,冻胶液黏度为50mPa·s,抗硫化氢高强度冻胶阀在125℃下3.5h后完全成胶,170h内保持冻胶性能不下降,成胶24h后每单位长度冻胶的封隔压力为0.08MPa,能有效抵抗10 000mg/L硫化氢气体连续24h侵入,体积分数10%的破胶剂可使冻胶60min内完全破胶。研究表明,抗硫化氢高强度冻胶阀具有良好的抗温性、粘壁性和较高的承压强度,能够满足含硫化氢地层欠平衡钻井安全的需要。When underbalanced drilling is carried out in Xinjiang Oilfield,the gel is eroded by rich H_2 S existed in the formation,and gel valves are severely affected by its working performance and life.In order to solve this problem,a series of studies were performed with high strength anti-H_2 S gel valves.At the simulated well temperature of 125 ℃,main polymers,organic crosslinking agents,ferric oxide（sulfide scavenger）and additives were selected in order,and optimized dosages to make up the gel.Experimental evaluation was performed on the basic performance of gel fluids,such as viscosity,gel strength,maximum sealing pressure and breaking capacity.Moreover,the effect of hydrogen sulfide on gel performance was evaluated by using anti-H_2 S evaluation apparatus.The results of evaluation showed that the viscosity of gel fluid was 50mPa·s,the high-strength anti-H_2 S gel valve could be completely formed into gel at the temperature of 125 ℃for 3.5hours,and performance kept no change for 170 hours.Twenty four hours after gelling,the sealing pressure per meter of gel was 0.08 MPa,which could effectively resist 24hours＇ continuous invasion of 10 000mg/L H2 S,and it may be broken completely within 60 minutes by adding the gel breaker with volume fraction of 10%.The research indicated that the high-strength anti-H2 S gel valve had good performance in temperature resistance,wall stickiness and bearing strength,and it can meet the safety requirements for the underbalanced drilling in H2S-bearing formations.

关 键 词：欠平衡钻井 冻胶阀 抗硫化氢 实验室试验 

分 类 号：TE249[石油与天然气工程—油气井工程]