The effect of small amounts of H 2 S on CO 2 corrosion of a carbon steel Conference Paper uri icon

abstract

  • © 1998 by NACE International. A large amount of effort has been invested trying to understand the mechanisms through which CO 2 and H 2 S act upon metallic surfaces. These efforts have led to different models, correlations or charts. However, present knowledge on the exact form under which these gases react on metal surfaces is far from complete. A particular aspect in which the amount of information is rather scarce is the effect of small amounts of H 2 S on an stream containing a large amount of CO 2 . The aim of this work is to determine the amount of H 2 S (critical concentration) that causes a maximum in the corrosion rate. Lab tests were done in order to determine the corrosion rate of A-516 steel in the presence of 5 % NaCl, at temperatures ranging from 50 °C to 150 °C and various H 2 S concentrations up to 40 ppm, under a total pressure of 3.27 MPa of CO 2 . Results showed that a concentration of H 2 S in the order of 10 ppm exist for which the corrosion rate reaches a maximum. Furthermore, this concentration was not dependent upon the temperature of the system within the range of study.

author list (cited authors)

  • Valdes, A., Case, R., Ramirez, M., & Ruiz, A.

publication date

  • January 1998