渤海某油田绒囊暂堵流体修井工艺

Workover technology using fuzzy-ball temporary plugging fluid in Bohai Oilfield

两口井试用证明绒囊暂堵流体可以解决渤海某油田修井过程中漏失问题,但其性能和施工工艺需要进一步优化.实验表明封堵深度0.1 m,无需挤入地层更多流体以形成更深封堵带即可实现有效封堵;绒囊暂堵流体封堵能力与密度无关,塑性黏度20-30 mPa·s、动塑比0.7-1.1 Pa/（mPa·s）即可封堵低压漏失地层.绒囊暂堵流体封堵后用标准地层水试漏,承压能力达25.64 MPa,表明无需全井循环即可实现漏失地层封堵.陆上S181 井气井全井筒段塞先导试验成功后,在渤海某油田A井储层段段塞封堵试用成功,表明绒囊暂堵流体在渤海某油田可以实施段塞封堵储层修井.

Trial use on two wells shows that the fuzzy-ball temporary plugging lfuid can address the problem of lost circulation during workover in Bohai Oilifeld, but its properties and operation process need to be further optimized. Experiment shows that the plugging depth is 0.1m, so effective sealing can be realized without injecting too much lfuid into the formation in order to create a deeper plugging belt. The plugging capability of fuzzy-ball temporary plugging lfuid has nothing to do with its density. The thief zone with low pressure can be plugged by such lfuid with 20~30 mPa·s plastic viscosity and 0.7~1.1 Pa/(mPa·s) rate of dynamic shear force. Leak test was conducted using standard formation water after being plugged by fuzzy-ball temporary plugging lfuid, the bearing capacity of the formation was up to 25.64 MPa, showing that the thief zone can be plugged without whole well circulation. After successful pilot test on whole well slug in onshore S181 Gaswell, the slug was trial used in reservoir section in Well A in Bohai Oilifeld, indicating that the fuzzy-ball temporary plugging lfuid can be used in workover operation by plugging the reservoir with the slug.