Integrity technology of storage and injection-production system of salt cavern gas storage: state-of-the-art

Integrity management is the development direction in the security management of gas storages. Storage and injection-production systems are the most important parts of salt cavern gas storages. Studying and implementing integrity management is of great significance for ensuring the safe operation of salt cavern gas storages. This paper reviews the progresses in risk assessment and integrity evaluation, which are the key technologies of integrity management in storage and injection-production systems. With respect to risk assessment, risk factors are identified, and quantitative risk assessment methods, which include methods for probability of failure calculation, estimation of failure consequences and risk assessment, are established. In terms of integrity evaluation, factors affecting wellbore damage and the types of damage are analyzed, and methods for the stability evaluation of gas storage cavern, integrity assessment of the casing with defects and prediction methods for fatigue life and erosion life of injection and production pipes are proposed.