Study on the process of submerged combustion vaporizer flue gas membrane-cryogenic hybrid carbon capture for coupled liquefied natural gas cold energy power generation

Under the background of "carbon peaking and carbon neutrality goals," China has put forward the requirements for the low-carbon development of Liquefied Natural Gas (LNG) industrial chain. Carbon capture technology is an effective means to reduce direct carbon emissions and can promote the decarbonization of the LNG industry chain. So far carbon capture is still an energy-intensive process. Based on the traditional membrane-cryogenic hybrid CO2 capture process, a membrane-cryogenic hybrid CO2 capture process coupled with Liquefied Natural Gas cold energy generation was proposed in this paper. In the proposed process, LNG cold energy and high temperature flue gas heat energy were used to drive Organic Rankine Cycle power generation and reduced carbon capture energy consumption. The effects of key parameters (membrane pressure, membrane temperature, cryogenic pressure, and cryogenic temperature) on the performance of the process (CO2 purity, CO2 recovery, and specific energy consumption) were analyzed by single factor analysis. The process parameters were optimized by response surface analysis, the optimized system resulted in an CO2 purity of 98.39%, CO2 recovery of 90.16%, and specific energy consumption of 605 kJ/kg which was much lower than that of the same type of carbon capture process. This process opens up a new technological path for the development of low energy consumption in carbon capture and the decarbonization of the LNG industry chain, and provides a new solution to meet the challenges in the context of "dual carbon."