An Advanced Cryogenic Air Separation Process Based on Self-heat Recuperation for CO2 Separation

An advanced cryogenic air separation process for oxy-combustion is proposed based on self-heat recuperation technology. Compared with the conventional double-column cryogenic air separation process, only one distillation column is used in the proposed process. The heat of N2 product gas from the top of the distillation column is recirculated by exchanging latent heat with the liquid O2 in the bottom and feed streams, largely reducing the energy consumption. The simulation results showed that the energy consumption of the proposed cryogenic air separation process was decreased by 30% comparing with the conventional process, when producing O2 with low purity (95 mol%) and low pressure (120 kPa).