In the wave of global energy transition，the innovation of energy storage technology is extremely important for ensuring stable energy supply and sustainable development. Deep underground salt caverns have become the preferred storage space for energy resources such as oil，natural gas，and hydrogen，due to their characteristic stability and containment，with extensive applications across the world and significant application results. Compared to the oil blanket method for cavern construction，cavern construction with nitrogen dissolution inhibition is safer and more efficient，environment friendly and cost effective for salt cavern energy storage facilities. This paper focuses on the cavern construction technology with nitrogen dissolution inhibition for salt cavern energy storage and presents a comparative analysis of cavern construction techniques with oil and gas blanket for dissolution inhibition. The cavern construction with nitrogen dissolution inhibition is clarified，including the wellhead workflow modification，on-site nitrogen injection process，and gas-liquid interface monitoring and control technique. It also lists and investigates application cases in both China and other countries. Based on a thorough literature review，this paper concludes the important effects of cavern construction with nitrogen dissolution inhibition on improving the construction efficiency of gas storage，reducing costs，and protecting environment. Moreover，the future development trend of this technology is explored.

As the development of oil and gas resources is continuously advancing toward deep water areas，deep and ultra-deep strata，complex geology and extreme wellbore conditions pose great challenges to the safe and stable production of oil and gas wells. Conventional wireline logging technology and casing packer leak detection technology can meet the technical requirements of wellbore integrity inspection，but they both require to shutdown wells and the costs of joint inspection are high. In recent years，the application of fiber optic sensing in petroleum industry has become increasingly widespread，opening up new ideas for real-time monitoring of wellbore integrity. By systematically summarizing the current development status of wellbore integrity inspection，the following prospects are made：（1） Permanently or semi-permanently placing optical cables in oil wells enables monitoring the temperature field，pressure field，stress field，sound waves，vibration，and fluids inside the wellbore in real time to provide direct data for evaluating the integrity status of oil and gas wells.（2） Fiber optic sensing technologies such as DTS and DAS are characterized by continuous，real-time and distributed measurement，for which it is preferred to place them during the well construction to deliver full lifecycle monitoring of oil and gas wells. However，the overall cost of fiber optic laying is relatively high，and the fiber optic layout method needs to consider the impact of pipe string insertion and cementing perforation operations. The fiber optic winding method and light source scattering type also have an impact on optical signal transmission and signal-to-noise ratio. Corresponding measures need to be taken to optimize the signal-to-noise ratio，improve the measurement accuracy and stability of the sensor.（3） Processing of fiber optic signals mostly relies on empirical methods determining the signal range in accordance with laboratory simulation experiments. However，considerable differences exist between the laboratory environment and the downhole environment. Therefore，it is still necessary to conduct wellbore experiments and establish measurement interpretation models based on the actual wellbore environment.

Due to the small casing diameter and the insufficient gas tightness of casing coupling threads，the old well cannot be converted into an injection-production well for the underground gas storage. Therefore，the old wellbore must be plugged and reconstructed to ensure effective plugging. An old well of the Ye County gas storage in Henan Province was taken as an example，and the well section to be milled and plugged was determined according to the formation lithology and well diameter. A three-dimensional finite element model of the cement plug-formation system based on Cohesive elements was built for the milling-plugging old well section，the peeling failure laws of the cement plug-formation interface under the constant-pressure condition were clarified，and the limit peeling length of the interface was computed. The results show that for old wells without perforated sections，it is necessary to set cement plug barriers in the cap rock and salt sections，respectively，to prevent natural gas leakage in the vertical and lateral directions. Under the gas storage condition with a constant pressure of 20 MPa，the bottom of the cement plug presents slight deformation after being compressed，resulting in the shear deformation of the cement plug-formation bonding interface，and peeling occurs，as such deformation accumulates to a certain extent. With the increasing simulation time，the length of the peeling interface gradually increases and approaches the equilibrium，and the ultimate peeling failure length is 18.4 m. Moreover，the peeling length decreases with the growing elastic modulus of the cement plug. It is recommended to use the high-elastic-modulus cement slurry system for well plugging. The findings of this research help to decide whether the milled-plugged section length of the old well in the field is sufficient，and provide theoretical guidance for ensuring the long-term safe operation of the gas storage.