页岩气侧钻水平井油基泥饼固化剂性能评价与现场试验

Performance Evaluation and Field Test of Oil-Based Mud Cake Solidification Agent for Shale Gas Sidetracking Horizontal Wells

摘要: 为进一步解决页岩气侧钻水平井环空带压难题，介绍了一种适用于油基钻井液条件下的油基泥饼固化剂GOS。性能评价结果表明：1) 养护条件为105℃ × 常压和油基泥饼厚度为0.3 mm时，随着养护时间的延长，采用油基泥饼固化剂的页岩气侧钻水平井固井二界面胶结强度增大且达到了0.1002~0.3974 MPa，而未采用油基泥饼固化剂的页岩气侧钻水平井固井二界面胶结强度则基本为0.0042~0.0082 MPa，即前者较后者的固井二界面胶结强度提高了19.44~53.43倍；2) GOS与油基钻井液和水泥浆具有良好的相容性，满足页岩气侧钻水平井固井作业要求。4口页岩气侧钻水平井的现场试验结果表明，固井质量合格率100%，固井一界面胶结质量优良率90%以上，固井二界面胶结中等以上的超过80%。其中，T1侧钻水平井目前已完成体积压裂测试，页岩气产量7.5013万方/日，页岩油产量9.87方/日，且油层套管与表层套管之间环空压裂前后均未出现带压，为页岩油气的高效勘探开发提供了良好的井筒保障。

Abstract: In order to further solve the problem of annular pressure in shale gas sidetracking horizontal wells, an oil-based mud cake solidification agent (GOS), which is suitable for the condition of oil-based drilling fluid, is introduced. The results of performance evaluation show that: 1) when the curing condition is 105˚C under normal pressure and the thickness of oil-based mud cake is 0.3 mm, with the prolongation of curing time, the cementing strength of the cement-formation interface in shale gas sidetracking horizontal wells with oil-based mud cake curing agent increases and reaches 0.1002~0.3974 MPa, while that in shale gas sidetracking horizontal wells without oil-based mud cake curing agent is basically 0.0042~0.0082 MPa. It means that the former is 19.44~53.43 times higher than the latter. 2) GOS has good compatibility with oil-based drilling fluid and cement slurry, which meets the cementing requirements of shale gas sidetracking horizontal wells. The field test results of four shale gas sidetracking horizontal wells show that the qualification rate of cementing quality is 100%, and the excellent and good rate of cementing quality of the cement-casing interface is more than 90%, more than 80% of medium cementation of the cement-formation interface. Among them, sidetracking horizontal well TY1 has completed volume fracturing test. The production of shale gas is 7.501³ × 104 m³/d and the production of shale oil is 9.87 m³/d. There is no pressure in the annulus between the production casing and the surface casing before and after fracturing, which provides a good wellbore guarantee for the efficient exploration and development of shale gas.