Experimental Investigation of Continuous Heat Extraction of Metal Oxides in a Moving Bed Reactor

Concentrated solar power (CSP) plants play an important part in climate-friendly power and heat generation. The volatile production during the day and the absence of solar radiation at e.g. high demand evenings can be met by combining CSP with thermal energy storage. Thermochemical storage materials, e.g. metal oxides, show high storage densities at temperatures suitable for CSP. Metal oxide granules play the central role in the investigated concept, where they act as heat transfer medium and thermal energy storage material. A 3 kW moving bed reactor for continuous heat extraction of metal oxide granules was constructed and put into operation. Inert operation proofed the general functionality of the reactor. The variation of inert particle mass flow indicated a direct influence on particle temperature during moving bed operation. The redox reaction of metal oxide was successfully observed with metal oxide as moving bed material.