Troubleshooting Alkanolamine Gas Treating Systems

An integral step in natural gas processing is the removal of the acid gas components such as carbon dioxide and hydrogen sulfide. Carbon dioxide must be removed prior to cryogenic separation of natural gas liquids, and hydrogen sulfide must be removed in order to comply with environmental regulations. The most common acid gas removal process consists of a closed-loop system in which a weak base alkanolamine solvent is used to absorb the acid gas, and steam is used to strip the acid gas from the amine and provide a lean amine solvent for the absorption process. Both the absorption and regeneration process take place in counter-current contactor towers with the amine solution as the liquid phase. Operational problems in amine systems can reduce capacity and result in unnecessary capital and operational expenses. This article explains some troubleshooting methods that can be used to identify the cause of poor performance in amine systems and restore those systems to optimal capacity, and illustrates their use in a real-world situation.