Dual moving bed calcium looping process: Optimizing CO2 capture efficiency and energy utilization

• Novel dual moving bed calcium looping CO 2 capture process configuration is proposed. • Moving bed CaL reduces the energy consumption by 8 % compared to conventional fluidized bed CaL. • Moving bed CaL CO₂ capture efficiency (97 %) is 3 % higher than fluidized bed CaL. This study proposed a dual moving bed reactor configuration for the calcium looping (CaL) process, aiming to improve CO 2 capture efficiency and reduce the energy consumption. A multistage thermodynamic equilibrium model was developed to simulate the gas-solid countercurrent reactive flow pattern. A comparative study was conducted between the proposed dual moving bed (DMB) CaL system and the conventional dual fluidized bed (DFB) configuration. At an R Ca/ C = 4, the gas-solid countercurrent moving bed carbonator can achieve a CO 2 capture efficiency exceeding 95 %, an improvement of over 3 % compared to the fluidized bed system operating at 650 °C. Internal countercurrent heat exchange of the MB carbonator increases the solid outlet temperature by approximately 60 °C, consequently reducing the calciner’s fuel consumption by 5.04 %. The gas-solid countercurrent flow in the calciner improved internal heat integration and further decreased fuel demand by 13.71 %. Thus, the DMB CaL system attained a calciner-specific energy consumption of 3.61 GJ/t CO 2 , representing a 19.78 % reduction from the DFB CaL system. When integrated into a coal-fired power plant, the specific energy consumption for CO 2 avoided (SPECCA) is 2.40 GJ/t CO 2 , an 8.40 % decrease compared to the DFB CaL process. This improvement enhances the techno-economic performance of the CaL process and highlights its potential for industrial CO 2 capture.