Assessment of energy recovery from carbonation process using mass and energy balance

Mineral carbonation technology, one of the carbon capture and storage (CCS) technologies, is mainly concerned with the reduction of harmful emissions of carbon dioxides (CO2) to the atmosphere. However, carbonation system requires extra energy for pretreatment of the feed stocks including mining, transport, grinding and activation (when necessary), disposal of carbonates and byproducts, etc. This extra energy is called energy penalty. Despite this energy penalty there is a growing interest in carbonation technology because of its several benefits (such as abundance of metal oxide bearing material, exothermic reaction, safe storage of CO2 in a stable solid form, etc) over other CCS technologies. In this study the mass and energy balance analysis of the carbonation system using Matlab/Simulink software is presented and discussed in order to assess the energy recovery from the carbonation products and reduction of CO2 emissions. Energy gain from the carbonation reaction is calculated with an aim that it will contribute to the self-sufficiency of energy requirement of the carbonation system. This may improve the overall efficiency of the power plant too. It is found from this study that at carbonation temperature below 423.15° K (150 oC), the carbonation system is energy self-sufficient with exothermic heat gain and no heat recovery is needed from the carbonation products. However, the energy recovery from the products is required when carbonation occurs at above 423.15° K.