摘要
Post-combustion carbon capture (PCC) using a chemical solvent is the most mature and well-proven technology to mitigate carbon dioxide (CO 2 ) emission. However, substantial energy consumption for solvent regeneration is still a critical challenge for widespread deployment of this PCC. In this study, a novel low-energy, combined rich and lean vapor recompression (RLVR) process for the CO 2 capture process using dilute aqueous ammonia (NH 3 ) solvent was developed and optimized by integrating of rich vapor recompression (RVR) and lean vapor recompression (LVR) approaches. A parametric study showed that the minimum total equivalent work can be obtained when CO 2 loading and NH 3 concentration of lean solution are 0.275 mol CO 2 /mol NH 3 and 5.0 wt%, respectively and the pressures of stripper, rich and lean solvent flash drums are maintained at 10.5 bar, 4.62 bar and 6.93 bar, respectively. Under such operation conditions, the total equivalent work required for a CO 2 capture plant was remarkably reduced to 0.123 kW h/kg of CO 2 captured, which is equivalent to about 10% energy penalty. This amounts to 26–54% reduction from recent literature reports. Furthermore, this combined RLVR process can completely eliminate the need of reboiler, leads to improving the flexibility of the capture plant since it can be separated from power plant steam systems.