(PS11001) The use of DP28WTM reduces passivation air in urea plant : Technology improvement

摘要

Sumitomo Metal Ind., Ltd.(SUMITOMO) and Toyo Engineering Corporation(TOYO) have performed intensive research to clarify how much oxygen can be safely reduced in urea synthesis loop. The research verified that duplex stainless steels, including higher Cr grade, required a certain amount of oxygen to form passive film in urea carbamate solution. The electrochemical measurement and immersion test results showed that DP28WTM had a great corrosion resistance in urea carbamate solution with low oxygen, and no active corrosion occurred on DP28WTM at low oxygen content. Passivation air introduced into synthesis loop can be drastically reduced by applying DP28WTM, which provides benefits such as safe operation, low energy consumption, low emission for urea plants.