牺牲阳极保护在LNG储罐海水试压中的应用

Application of Sacrif icial Anode Protection in Seawater Pressure Testing of LNG Storage Tanks

以淡水为试压介质相比,以海水为试压介质虽然具有取水方便、成本较低等优点,但海水是一种腐蚀性很强的天然电解质溶液,对LNG储罐内罐具有较强的腐蚀性,因此常采用牺牲阳极阴极保护法对储罐内罐进行防腐蚀保护。文章对牺牲阳极阴极保护法进行了简单阐述,并给出了牺牲阳极阴极保护法在LNG储罐试压中的设计和应用实例。应用实例证明以海水为实际试压介质并采用牺牲阳极进行保护,可以有效地对罐壁和罐底等部位的X7Ni9进行防腐蚀保护。

Compared to using fresh water as the pressure testing medium,using seawater as the pressure testing medium has the advantages of convenient water extraction and low cost.However,seawater is a highly corrosive natural electrolyte solution that has strong corrosiveness to the inner tanks of LNG storage tanks.Therefore,sacrif icial anode cathodic protection method is often used to protect the internal tanks from corrosion.This article provides a brief explanation of sacrif icial anode cathodic protection method and provides a design and application example of sacrif icial anode cathodic protection method in LNG tank pressure testing.The application example proves that using sea water as the actual pressure testing medium and sacrif icial anode protection can effectively protect X7Ni9 on the tank wall and bottom and other parts from corrosion.