Development of Acid Gas Purification for Higher CO2 Capture and Low Energy Consumption

An integrated acid gas purification process with higher CO₂ capture rate is proposed, which is featured by Rectisol® process heat integrated with CO₂ multistage compression. Three key factors contribute to CO₂ capture rate have been identified, which also serve as the foundation to process energy consumption and cost analysis. Compared with the conventional Rectisol® process, proposed process realize CO₂ capture rate of 80-95 %, which remarkably reduce CO₂ emission and collect highly concentrated CO₂ for further processing and utilization. Energy consumption of the proposed acid gas purification process first decrease and then increase as CO₂ capture rate increases. The energy consumption reaches the lowest point of 0.93 GJ/t CO₂ when the CO₂ capture rate is 80 %. Although CO₂ capture rate of the proposed process can be as high as 95 %, a reasonable CO₂ capture rate within 80-90 % is recommended to achieve the best economic and environmental performances.