Research on Process of SCV Flue Gas Carbon Capture Based on LNG Cold Energy

Under the guidance of China's goal of achieving carbon neutrality by 2060, the petrochemical industry is increasingly adopting energy-saving and emission-reduction technologies. To realize the low carbon operation of the LNG (liquefied natural gas) receiving terminal, an innovative SCV (submerged combustion vaporizer) flue gas carbon capture system using LNG cold energy was established, and the system also combined with an ORC (organic Rankine cycle). HYSYS software was used to simulate the process of the SCV flue gas carbon capture system and the LNG regasification system. The simulation results showed that the proposed system has low carbon emission and low energy consumption performance. Moreover, the sensitivity analysis of the evaporation pressure of working fluids, CO2 capture pressure, and CO2 capture temperature was carried out. The key parameters were optimized by HYSYS software to achieve the optimal operation cost of the system. When the evaporation pressure of working fluids, CO2 capture pressure, and CO2 capture temperature were set as 1300 kPa, 750 kPa, and 143.15 K, respectively, the optimized system resulted in an exergy efficiency of 13.63%, an LNG cold exergy utilization rate of 77.49%, a CO2 capture rate of 94.9%, and a CO2 capture capacity of 6620.4 kg/h.