摘要
固井防窜一直是困扰石油工业多年的问题,因水泥浆候凝期间的环空有效静液柱压力不断降低,在其降低到地层流体压力之后,水泥浆能不能抵御地层气体对其液相的置换是固井防窜的关键。为此,从水泥浆窜流能力评价方面着手,结合现场井况和固井工艺的水泥浆窜流试验方法,对目前常用的一些防窜材料,诸如成膜类、AMPS合成共聚物类、改性纤维素类降滤失剂及胶乳、膨胀剂、微硅等的窜流性能进行了评价。结果表明:在不同条件下各类外加剂的防窜特性不一,低温下成膜聚合物水泥浆的防窜性能有一定保障,但随着温度的升高,其性能就会受到一定影响;胶乳水泥浆体系的防窜能力相对较稳定,在不同条件下保证胶乳的有效掺量就可以保障水泥浆的防窜性能。实验评价结果在川渝地区、长庆苏南、吐哈鲁克沁、玉门酒东等气田进行了超过150口井的胶乳水泥浆现场应用,未发生窜流,固井效果良好。
Gas channeling prevention in cementing has always been a challenge in the oil and gas industry for many years. During the time the cement slurry sets, the effective static pressure in the annulus continuously falls; and when it reaches the formation fluid pressure, the cement＇s resistance against the formation gas displacing its liquid is crucial to successful gas channeling prevention in cementing. In view of this, tests were firstly performed on the basis of field conditions with corresponding methods to evaluate the gas channeling prevention of several popular cement additives at present, including film forming polymer, copolymer of AMPS, fluid loss agent of modified cellulose, latex, swelling agent, micro silicon, etc. The results showed that under different conditions, each additive has distinctive properties in the performance of gas channeling prevention： such performance of the film-forming polymer slurry is favorable at low temperatures but decreases as the temperature rises; the latex cement slurry has a relatively stable per- formance and the cement can resist against annular flow if effective of latex is added in accordance with the conditions. After the latex cement slurry was applied in over 150 wells of many gas fields in the Siehuan Basin, the southern block of the Sulige Gas Field, the Lukqun Block in the Tuha Oilfield, the Jiudong area of the Yumen Oilfield, etc., the cementing operations were all successfully ful- filled with a satisfying performance of gas channeling prevention.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2013年第11期79-85,共7页
Natural Gas Industry
基金
中国石油天然气集团公司基础研究项目(编号:2008A-2304)部分成果
关键词
固井
防窜
评价
水泥浆
静胶凝强度
降滤失剂
防气窜剂
膨胀剂
cementing, anti-migration, evaluation, cement slurry, static gel strength, fluid loss agent, anti-migration agent, swelling agent
