缝洞型碳酸盐岩气藏试气投产一体化技术

An integrated formation testing and production technology in fractured-vuggy carbonate gas reservoirs

张文斌 张明友 贺秋云 黄靖富 谢奎 魏国安

ZHANG Wenbin ZHANG Mingyou HE Qiuyun HUANG Jingfu XIE Kui WEI Guoan

川庆钻探工程有限公司试修公司 川庆钻探工程有限公司国际工程公司

Well Testing and Workover Company, CNPC Chuanqing Drilling Engineering Co., Ltd., Chengdu 610000, Sichuan, China International Engineering Company, CNPC Chuanqing Drilling Engineering Co., Ltd., Chengdu 610000, Sichuan, China

缝洞型碳酸盐岩天然气储层裂缝发育，此类储层在试气后封堵或投产前压井极易发生漏失，且漏失量大、漏失速度快，存在易漏难堵、漏喷同存的情况，为此，设计了“试气—暂堵—投产”一体化管柱，形成了以压控式井下脱手回接开关阀为核心工具的试气投产一体化技术。利用该技术，通过环空加压能快速封堵储层，可在不压井状态下起出上部管柱，可在清水或低密度工作液中回接完井管柱沟通储层，无需诱喷即可生产。现场应用表明，该技术可有效避免缝洞型碳酸盐岩储层试气后压井漏失问题，显著降低储层伤害，提高储层初次投产采收率，具有良好的推广应用前景。

Natural fractures are well developed in fractured-vuggy carbonate gas reservoirs, which are prone to lost circulation during plugging after formation testing or killing before production. Moreover, such lost circulation presents large volumes and high rates, and the complex cases of high lost circulation proneness and high difficulties in plugging, and lost circulation associated with kickoff are sometimes encountered. An integrated pipe string for formation testing–temporary plugging–production was designed, and an integrated formation test and production technology, enabled by the core tool of the pressure-controlled downhole disconnection on/off valve, was developed. With the presented technology, the reservoir can be quickly plugged by annulus pressurization; the upper pipe string can be tripped out without killing; the completion string can be tied back in clear water or low-density working fluids to connect the reservoir, which allows for production with no induced flow. Field applications showed that this technology can effectively avoid lost circulation during well killing after formation testing in fractured-vuggy carbonate gas reservoirs, significantly reduce reservoir damage, and improve recovery factor of primary production. The presented technology has excellent prospects for application promotion.

10.13639/j.odpt.202208002