(235a) Performance of Innovative Stripper Options for Co2 Capture

The state-of-the-art technology for the capture of CO₂ from coal-fired power plants is aqueous absorption / stripping. The technology has been applied in small plants but requires some innovations for application in large power plants because of its energy -intensive nature. It is estimated that the operating cost of running this system constitutes a 15 ? 30% energy hit to the power plant. Running the stripper under optimized conditions with the use of more efficient contactors could help reduce capital costs. In this paper, we present results of simulating different process alternatives including (1) using a more reactive solvent (2) operating the cross exchanger at a lower temperature approach (3) optimizing the stripper operation (4) using innovative configurations such as vacuum and multipressure strippers. The model was developed in the Aspen Custom Modeler (ACM) Simulation Environment and includes thermodynamic studies, reaction rate measurements, physical and contactor specific information using three stripper configurations ? a simple, vacuum and multipressure stripper for two solvents 7m monoethanolamine (MEA) and 5m K⁺ / 2.5m PZ. With some approximations, the use of solvents with varying heats of desorption are investigated and an optimum heat of desorption that minimizes reboiler duty and equivalent work is proposed.