Abstract
The high amine concentration treating plants which used 65wt% aqueous solution of diglycolamine were newly constructed by Teikoku Oil Co., Ltd. to remove carbon dioxide from the natural gas produced in Nagaoka, Niigata prefecture, Japan. SUS 304 stainless steel was used to places at which aggressive corrosion was suspected. On the inspection on the inside of the plants after one year operation, aggressive uniform corrosion of stainless steel was observed to occur on the pall rings installed in the bottom of the absorber, on the inside of the heat exchanger tube and of the upper part of the stripper, and so on. All the places which aggressive uniform corrosion occured were where contacted with the amine solution absorbing high concentration of carbon dioxide. The article introduces an anomalous, aggressive uniform corrosion of stainless steel found in the high amine-concentration treating plans for raw natural gas.