Failure Analysis of String Corrosion and Its Protection during Constructing and Operating Gas Storage Facility in Bedded Salt Deposit

With more and more salt cavern gas storage under construction, the corrosion problems of leaching string, production string, and production casing require more attention by experts o gas storage. This paper introduces several corrosion phenomena which are encountered during the operation of leaching salt caverns, and natural gas injection and withdrawal. The main corrosion factors are discussed such as brine, air, microbes, components of natural gas, gas injection velocity, operating status and others. The corrosion mechanisms are also analyzed. Inorder to prevent the corrosion effects a series of measures are applied successfully during different construction phases of the gas storage facility in the Yangtze River Delta, such as oxygen scavenger and biocide, coating protection, annulus protection liquid, cathodic protection.