To meet the economic boom, energy storage becomes more and more important for China’s development in nowadays. As a part of the nation’s energy storage strategy, large-scale underground constructions have been building in China. The Caverns in deep salt rocks, with its high withdrawal and injection rates, are often utilized as underground storage sites in which petroleum and natural gas are stored.
Focus on solving the key scientific and technical issues on energy storage in deep bedded salt rocks, significant works have been carried out by IRSM researchers to serve the demands for the constructions. The main achievements are shown as follow:
1. Investigating systematically the characteristics of interface between salt and interbed, and, moreover, proposing a constitutive model and the numerical model which describe well the mechanical behaviors of the bedded salt rocks;
2. Presenting static stability criterions based on the damage of multi-layer salt rocks, and availability criterions of salt cavern long-term operation considering the reinforcement effect of interbeds;
3. Proposing a test system of bedded salt rocks mechanics evaluation (i.e., compression test, shear test, tension test, creep test, and microscopic test), a test system of salt cavern tightness estimation (i.e., gas tightness test, in site high-pressure water injection test, and salt cavern water injection test), and a numerical analysis system of salt cavern long-term operation;
4. Establishing the determining methods of parameters for salt cavern designing and running, including the distance between casing shoe and cavern top, depth of protection salt, optimal cavern shape, thickness of safety pillar, maximum and minimum operating pressure, speed of gas injection and production, and so on; and
5. Revealing the mechanisms of interbeds collapse during solution mining process, and proposing a technique of controlling interbeds collapse in solution mining for oil/gas storage construction in bedded salt rocks.