Research On Corrosion And Protection Of Equipments In WSA Sulfuric Acid Unit

The article describes the technological principle and development trend of H2S sulfuric acid making plant. It mainly researches the technological principle, technical features, technical procedure and techno-economic for WSA wet sulfuric acid making of Topsoea Company (Denmark). It analysis the corrosion and anticorrosion of H2S sulfuric acid making plant domestic and abroad and includes that the corrosion questions which happened in Changling Petrochemical Company are not same as other company. In allusion to the instance, we research and analysis the reasons of the corrosion for finished concentrated sulfuric acid pipes and process gas cooler E104 pipes in WSA sulfuric acid plant in Changling Petrochemical Company. The reasons are related to the fault of welding quality. The welding beam and base metal beam have many differences. They have different energetic. The electrochemical activity in welding area is higher than it in the base metal beam. The electrochemical corrosion is easy to happen for the medium. The corrosion of concentrated sulfuric acid is related to the temperature and the impurity content. The corrosion rate is raised up when the temperature is higher. If the sulfuric acid has some ion nitrated , the pipe corrosion will raise up, too. The product's color is unusual. The article puts forward some anti-corrosion measures and suggestions about pipe erosive-restant lining, corrosion monitoring, process corrosion protection, improving welding process, replacing instrument air and using Cr-Mo steel anti-corrosion material. At last it prospects the research way in the future.