Separation and purification of carbon dioxide is current research hotspot. With increasing needs for environmental protection

traditional single separation techniques are difficult to meet these discharge specifications. Integration of multiple separation methods has gradually gained research attention. Separation and recovery of carbon dioxide in the integrated gasification combined cycle (IGCC) process was studied by process simulation and polynomial state equations were obtained for such system. Furthermore

a mathematical superstructure model of hybrid membrane-cryogenic flash distillation was established. Optimal separation sequence was found by targeting minimal annual cost at pre-set lower specification of product purity and recovery. The optimized process show excellent separating performance of membrane after flash configuration and multistage membrane structure. Compared to control process

optimized process not only guarantees product recovery and purity but also decreases total annual cost by almost 27%.