Amine Corrosion in Gas Sweetening Plant: Causes and Minimization on Real Case Study

摘要

Corrosion in amine units is fairly complex since it involves various corrosion, erosion and cracking mechanisms and is affected significantly by process parameters and materials of construction. The amine itself is not corrosive, but corrosion is promoted by the following: 1. Dissolved acid gases 2. Higher concentration of corrosive species i.e. HSAS (Heat Stable Amine Salt). 3. High temperatures After more than seven years using methyldiethanolamine (MDEA) in the four gas sweetening trains during the internal inspection of regenerator and regenerator Reboiler, which was followed by UT thickness measurement on the related pipe work, noticeable corrosion was observed on the column body, Reboiler shell and vapour exit pipe from the Reboiler. The appearance of corrosion mechanism shows acidic medium attack on the carbon steel wall. This paper is presented as a practical guide to identifying the causes of corrosion in different sections of gas sweetening trains and ways to control and minimize corrosion in amine plants. The finding of the survey emphasize the importance of careful process control and the beneficial effect of upgrading material to austenitic stainless steel in a number of areas.