Corrosion Analysis and Protection of Liquid Sulfur Pool in High Sulfur Content Natural Gas Purification Plant

Abstract In light of the corrosion failure observed in the liquid sulfur pool at a purification plant characterized by high sulfur content in northeastern Sichuan Province, an analysis was conducted on the structure, corrosion products, and mechanisms of corrosion to ascertain their elemental composition and underlying causes. Subsequently, appropriate corrosion protection measures were proposed. The results show that the liquid sulfur pool structure of the high sulfur content purification plant consists of 200 thick C40 heat resistant concrete structure layer, waterproof layer, heat insulation layer and acid resistant anticorrosive layer, and the pool is cast with concrete. Through the detection and analysis of the corrosion products, the outside of the corrosion products are mainly O, S and Cr elements, and the inside of the corrosion products are mainly O, S and Fe elements. Through the analysis of environmental media, the corrosion mechanism is analyzed. The liquid sulfur pool is mainly composed of four corrosion environments: low temperature wet H 2 S corrosion environment, sulfuric acid dew point corrosion environment, solid sulfur corrosion environment and atmospheric corrosion environment. Finally, the corrosion protection measures of “upgrading stainless steel roof material+adopting high temperature resistant silicate concrete material+optimizing anti-corrosion process of liquid sulfur tank lining” are proposed.