PROCESS FOR CO2 REMOVAL

摘要

A continuous process for acid gas removal from process gas streams by contact with an aqueous alkanolamine solution such as MEA wherein the temperature of the MEA solution is controlled by placing an intercooler at the lower end of the absorption column such that the temperature of the down-coming MEA solution is cooled to allow increased mole loading of acid gas in the solution, but is not so cooled that the mass transfer rate of the acid gas from the process gas to the MEA solution is slowed to an unacceptable level. The lower temperature highly loaded MEA solution is then passed to a heat exchanger-flash-heat exchanger arrangement where the temperature is increased to provide satisfactory flash efficiency and then heated again prior to introduction into the stripper to reduce the sensible heat duty in the stripper. The combination of optimally positioned intercooler and flash together with the temperature ranges recited permit the obtainment of a net energy demand lower than can be expected from the addition of the intercooler effect and the flash effect.