Abstract
Erosion-corrosion of S43400stainless steel in high temperature and high pressure (HTHP) CO2-O2 environment was investigated by high temperature and high pressure autoclave compared with S31603stainless 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 S43400stainless steel showed a similar low erosion-corrosion rate compared to S31603stainless steel under low Cl- concentration medium. With the increase of Cl- concentration, erosion-corrosion rate of S43400stainless steel increased obviously compared with S31603stainless steel. Cl- concentration had significant effect on erosion-corrosion rate of S43400stainless steel in CO2-O2 environment. Cl- had a significant effect on stability of passive film of S43400stainless steel. In solutions with two different Cl- concentrations, the stability of passive film on S43400stainless steel was low, while S31603stainless steel had stable passive film. In high temperature and high pressure CO2-O2 environment with sand, erosion-corrosion resistance of S43400stainless steel was mainly determined by stability of passive film rather than mechanical effect of sand-containing liquid.
