The present study proposes a multi-stage CO2 capture process that incorporates heat-exchangeable fluidized-bed reactors. For continuous multi-stage heat exchange, three dry regenerable sorbents: K2CO3, MgO, and CaO, were used to create a three-stage temperature-dependent reaction chain for CO2 capture, corresponding to low (50-150°C), middle (350-650°C), and high (750-900°C) temperature stages, respectively. Heat from carbonation in the high and middle temperature stages was used for regeneration for the middle and low temperature stages. The feasibility of this process is depending on the heat-transfer performance of the heat-exchangeable fluidized bed reactors as the focus of this study. The three-stage CO2 capture process for a 60Nm3/h CO2 flow rate required a reactor area of 0.129 and 0.130m2 for heat exchange between the mid-temperature carbonation and low-temperature regeneration stages and between the high-temperature carbonation and mid-temperature regeneration stages, respectively. The reactor diameter was selected to provide dense fluidization conditions for each bed with respect to the desired flow rate. The flow characteristics and energy balance of the reactors were confirmed using computational fluid dynamics and thermodynamic analysis, respectively.
Bibliographical noteFunding Information:
This work was supported by the Korea CCS R&D Center (KCRC) grant funded by the Korea Government (Ministry of Education, Science and Technology) ( No. NRF-2014M1A8A1049330 ).
© 2015 Elsevier Ltd.
All Science Journal Classification (ASJC) codes
- Civil and Structural Engineering
- Building and Construction
- Mechanical Engineering
- Industrial and Manufacturing Engineering
- Electrical and Electronic Engineering