Optimal design of an MDEA CO2 capture plant for low-carbon hydrogen production - A rigorous process optimization approach

This work presents an optimized design of a methyl diethanolamine CO2 capture unit for clean hydrogen production via steam methane reforming of natural gas, where CO(2 )is captured from the pressurized water-gas shifted syngas. We propose a modified version of the standard MDEA-based CO2 capture process flowsheet, and we optimize the operating conditions by solving a multi-objective optimization problem to minimize energy consumption while maximizing the CO2 capture rate. In this paper, we opted to model the CO2 capture plant using an equilibrium-based approach. To validate the optimization results obtained and to verify the absorber and desorber dimensions, we sized both columns. Packing heights remain below the threshold of 15 metres and productivity ranges between 0.74 tCO(2)/m(3)h at a capture rate of 90% and 0.35 tCO(2)/m(3)h for a CO2 recovery of 99.8% respectively.