Application of Drilling and Production Engineering Technologies for Gas Storage in Changqing Lithologic Gas Reservoirs

The low permeability and low pressure lithologic gas reservoirs in Changqing area are plagued by complex geological conditions, great difficulties in safe drilling, and high contents of corrosive media. These issues pose challenges to the construction and operation of gas storage facilities. Based on the practical experience of drilling and production engineering technologies for gas storage in the Changqing gas region over the past decade, this paper conducts technical research in five aspects: safe and efficient drilling of low pressure reservoirs, wellbore integrity assurance technologies, coiled tubing jet acidizing technology, tubing material selection and corrosion prevention, and comprehensive utilization and repair of old wells. It summarizes the key technologies and research progress of drilling and production engineering for gas storage in low permeability and low pressure lithologic gas reservoirs. On this basis, the existing problems and development directions in aspects such as high speed drilling, hydraulic fracturing, wellbore integrity monitoring and early warning, annulus pressure treatment and repair, plugging of reused and abandoned wells, and plugging of horizontal wells with complex pipe strings are put forward. To a certain extent, this provides a reference for the scientific design, efficient construction, peak shaving injection and production, and safe operation of gas storage facilities.