关键词: 储气库, 环空起压, 光纤, 漏点, DTS, DAS

Abstract: After the gas storage well was put into production, it has undergone multiple cycles of injection and production and has been subjected to longterm alternating load changes. Pressure buildupmay occur in the oil pipe and oil sleeve annulus, oil sleeve and technical sleeve annulus, and technical sleeve and gauge sleeve annulus; meanwhile, longterm exposure to high pressure in various levels of the annulus can easily damage the integrity of the wellbore seal, causing natural gas injection leakage. This may affect well control safety and normal production. There are over a dozen reasons that may cause pressure buildup in various levels of the annulus. Current monitoring data covering pressure, temperature in injection/production wells, and annulus protection fluid level alone cannot accurately identify leakage points or specific leakage pathways in this gas storage.To enable precise remediation and effective control of annulus pressure buildup, fiberoptic monitoring methods based on DTS (Distributed Temperature Sensing) and DAS (Distributed Acoustic Sensing) technologies have been introduced.This paper introduces the principles of DTS and DAS fiberoptic monitoring technologies, along with their application in several typical wells. The results demonstrate that these technologies can effectively pinpoint leakage locations, providing support for targeted remediation of annulus pressure buildup. This approach also serves as a valuable reference for the treatment of annulus pressure buildup wells in other gas storage facilities.

Key words: gas storage, annulus pressure buildup, fiber optic, leakage point, DTS, DAS