Debrining prediction of a salt cavern used for compressed air energy storage

Using salt caverns for compressed air energy storage (CAES) is a main development direction in China to provide a continuous power supply produced by renewable energy (e.g., solar, wind, tidal energy). A mathematical model used to predict the debrining parameters for a salt cavern used for CAES is built based on the pressure equilibrium principle. Combined with the sonar survey data of a salt cavern, the equations are deduced for calculating the debrining parameters. A mathematical model is proposed for the calculation of the critical safe distance between the air and brine interface (AB interface) and debrining tubing inlet. Based on above mathematical models, a program is developed using Visual Basic computer language. A salt cavern of Jintan salt district, Changzhou city, Jiangsu province, China, is simulated as an example. Results show the tubing size is the most important parameter for improving debrining efficiency. The tubing with diameter and wall thickness of 139.7 mm × 6.98 mm is proposed in the CAES cavern debrining to replace the one with size of 114.3 mm × 6.88 mm used in the traditional debrining for the salt cavern gas storage of Jintan. This can decrease the total debrining time by 43%, and only increases energy consumption by about 10%. This study can provide a theoretical foundation and a technological reference for the debrining of Jintan salt cavern used for CAES.