Study On Subsurface Characteristics For Salt Deposits In China And Geological Eevaluation On Salt Cavern Storage

Energy storage is a critical component of future sustainable energy systems that are likely consisted of fossil and increasingly renewable energy sources. Underground salt cavern, which is one of the fourth underground cavern types, is believed to be a leading option for large-scale oil-gas storage based on its advantages of excellent physical characteristics, favorable geological condition and environmental friendly. A good understanding of the salt distribution and viability for salt cavern oil-gas storage is essential for the design and deployment of future energy systems in China. At present, the study of salt cavern in our country has got some progress, but it still belongs to new areas.According to analyse the depth (top of salt600-2500m), thickness (>100m) and impurities (total impurities<20%) and the current status of exploitationthe of every mining salt deposit, we make a selection and get the following results.①We have made7salt basins (regions) as the key work in the future. We advice Subei basin, Jianghan basin, Ordos basin, and Bohaiwan basin as the sites of salt cavern gas storages; Tarim basin, Shanganning region and Lanping-Simao basin as salt cavern nuclear waste storages.①According to the geological conditions of salt deposits,13salt deposits has been screened out as the targets of further exploration, six of which have already been selected as the target sites by China.③To make an improvement and quantitative about the evaluation index information. At present, although there is a relatively complete evaluation system (a combination of expert evaluation method and analytic hierarchy process), but the salt mine research degree is different, complete information degree is differ, it is unable to make the final evaluation.④To make full use of old cavities. Old cavities have the advantages of shorten database construction time, decrease investment in building salt cavern and relieve the digestion about brine, which are considered to be the most effective and fast way to built salt cavern. ⑤Because of the cost of mining salt deposits are relatively high, which is mainly for civil, and sea salt is rich in our country, so we should make use of salt cavern and achieve win-win situation.⑥To make full use of wind and solar energy. Salt cavern are used for H2is a new conception, choosing regions where intermittent renewable energy such as wind and solar energy is abundant and providing feasible proposal for the mining of salt deposits in our country.After all, it is a key work for our country to built salt cavern gas storage, combined the advantages of salt cavern gas storage to mined salt deposits is a significant thing for the program of strategic reserves of energy. And there are still amounts of geological work to do to make the final selection of salt cavern storage sites.