Energy recovery opportunities from mineral carbonation process in coal fired power plant

Various carbon dioxide (CO2) capture and storage (CCS) technologies are available worldwide to mitigate the effects of global warming. Mineral carbonation technology is one of the types of CCS technology. In this process gaseous CO2 is converted into geologically stable carbonates. This process has some potential advantages compared to other available CCS technologies which have attracted the attention of researchers for further development of this technology for sequestering CO2. One of the potential benefits of this technology is its exothermic reaction process. This exothermic heat energy can be recovered and used in other energy consuming components of carbonation plant. Heat energy from the products of the carbonation process can also be captured. This technology has not fully been developed yet, in particular for implementing it into power plants. In this study a thermodynamic mass and energy balance model is developed using Matlab/Simulink software for investigating energy recovery opportunities. Wollastonite mineral is used as feed stocks. The amount of heat energy which can be recovered at different carbonation temperatures is determined and analysed for a case study power plant with capacity of 1400 MW. It is found from this study that the carbonation process in case study power plant is energy self-sufficient, even only by the exothermic heat produced from the reaction and no heat recovery is needed from the products of carbonation process. It is also found that the energy required to supply to the carbonation plant (i.e. to grinder and compressor) decreases with increase in carbonation temperature. The surplus exothermic heat energy and heat energy from carbonated products can be utilized to reduce the fuel energy required for the existing power plant.