Investigation of Corrosion Behavior of Drain Pipes of Process Compressors in Direct Reduction Unit

Corrosion is a natural destruction process of industrial components. Process compressors were employed to meet the gas pressure and flow of the process in the direct reduction unit, while carbon steel pipes were used to separate water from the gas. However, the pipes were punctured and had water and gas leakage in a shorter time than the other units. In order to examine the destruction causes, several samples of the destructed pipe were studied by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results showed that, in addition to regular factors such as high temperature and acidic medium, microbial corrosion by sulfate-reducing bacteria and H2S gas worsened local and sub-sediment corrosion so that the component would be destructed in a shorter time. The presence of the FeS layer would result in severe local corrosion.