CO2 capture in industry using chilled ammonia process

Sammanfattning: CO2 capture and storage (CCS) is estimated to reduce 14% of the global CO2 emissions in the 2 °C scenario presented by the International Energy Agency. Moreover, post combustion capture is identified as a potential method for CO2 capture from industry since it can be easily retrofitted without disturbing the core industrial process. Among the post-combustion capture methods, absorption using mono-ethanol amine (MEA) is the most mature technology that has been demonstrated at plant scale. However, using chilled ammonia process as a post combustion capture technology in a cement industry can reduce 47% energy penalty for CO2 capture when compared to the conventional MEA absorption method.  Hence, the current project aims at analyzing the chilled ammonia process when integrated with steel and ammonia plants. Key performance indicator like specific primary energy consumption per kilogram of CO2 avoided (SPECCA) is estimated and compared with MEA absorption method. Firstly, chilled ammonia process (CAP) for cement plant was used as reference case. Then, CAP for steel and ammonia processes was optimized by the means of the decision variables affecting the capture and energy efficiency. The energy consumption per kg CO2 captured and SPECCA was lower for the higher CO2 concentration in the flue gas. Results for SPECCA were 3,56, 3,52 and 3,61 MJ/kg CO2 for cement, steel, and ammonia plants, respectively.