Simulation and Economic Analysis of MEA+PZ and MDEA+MEA Blends in Post-combustion CO2 Capture Plant

Abstract

The energy requirement of the amine based CO2 capture process is the main drawback of the technology. Studies on energy demand reduction are therefore important. This work presents energy optimization and economic analysis of an 85% CO2 capture process using pure monoethanolamine (MEA), and processes with blends of methyl diethanolamine (MDEA) and piperazine (PZ). The process with 30 wt% MEA was the base (reference) case in this study. The regeneration energy requirement for the base case was 3.77 GJ/tCO2. The blends of (30 wt% MEA+5 wt% PZ) and (30 wt% MEA+15 wt% MDEA) were calculated to achieve 4.9% and 7.5% reduction in regeneration energy respectively. The economic analysis also indicated that 4.1% and 4.3% total annual cost savings can be achieved by the MEA+PZ and MEA+MDEA blends processes respectively. The work further shows that the cyclic capacity is enhanced by using these blends instead of pure MEA.