Effect of Cl~- Concentration on Erosion-corrosion Behavior of S43400 and S31603 Stainless Steels in High Temperature and High Pressure CO_2-O_2 Environment

摘要

Erosion-corrosion of S43400 stainless steel in high temperature and high pressure (HTHP) CO_2-O_2 environment was investigated by high temperature and high pressure autoclave compared with S31603 stainless steel. Further, by immersion test and electrochemical test of two stainless steel in two different HCI solutions, the effect of Cl~- concentration on erosion-corrosion behavior in sand-containing solution was analyzed and interpreted. The results suggested that S43400 stainless steel showed a similar low erosion-corrosion rate compared to S31603 stainless steel under low Cl~-concentration medium. With the increase of Cl~- concentration, erosion-corrosion rate of S43400 stainless steel increased obviously compared with S31603 stainless steel. Cl~- concentration had significant effect on erosion-corrosion rate of S43400 stainless steel in CO_2-O_2 environment. Cl~- had a significant effect on stability of passive film of S43400 stainless steel. In solutions with two different Cl~- concentrations, the stability of passive film on S43400 stainless steel was low, while S31603 stainless steel had stable passive film. In high temperature and high pressure CO_2-O_2 environment with sand, erosion-corrosion resistance of S43400 stainless steel was mainly determined by stability of passive film rather than mechanical effect of sand-containing liquid.