Power generation based on the Ca(OH)2/ CaO thermochemical storage system - Experimental investigation of discharge operation modes in lab scale and corresponding conceptual process design

Therefore the thermal discharge of the reaction system at vapour pressures between 4 and 470 kPa and temperatures between 280 and 600 °C is experimentally investigated in this study. In particular the influence of the cooling load at various vapour pressures on the achievable discharge temperatures is analysed. The presented data complements the experimental characterisation of the reaction system in the complete temperature and pressure range which is relevant for real process applications. Based on this knowledge the applicability of the storage for various processes can now be assessed more accurate. By means of the experimental results a first integration option of the thermochemical system in a CSP plant is proposed in this work and thermodynamically analysed. The analysis revealed that, when the required steam production during discharge is thermally integrated into the Rankine steam cycle, a high storage efficiency of up to 87% can be reached compared to only 60% in the reference case.