1992 Volume 41 Issue 7 Pages 447-452
A new boiler to work with highly concentrated water was designed to study the effect of dissolved oxygen (DO) on corrosion behavior of carbon steel in high temperature and high pressured boiler water system. The operational characteristics of the new test boiler were examined and it was confirmed that the new test boiler exemplified actual boilers in terms of strength factors such as heat transfer rate, blow rate, recirculating rate and linear velocity rate. With maintaining the temperature of boiler water at 150-200°C, the corrosion behavior of carbon steel with a heat flux was examined under the different concentration of DO and/or cycles of concentration of boiler water. It was found that there was a critical value of DO (DOcri), which was defined that no ferrous ion was detected below DOcri and the amount of dissolved ferrous ions (WFe) increased remarkably with increasing DO above DOcri, and DOcri was dependent on the cycles of concentration of boiler water. The results showed that a small amount of DO caused serious corrosion of carbon steel in high temperature and highly concentrated boiler water.
