Seasonal Thermochemical Heat Storage: First Measurements on a Falling Film Tube Bundle Laboratory Setup
Abstract
Thermochemical energy storage in aqueous sorbents is a promising technology for long-term - seasonal – application. In an absorption system the absorption-desorption and evaporation-condensation heat and mass exchangers form the power unit. The tanks containing the sorbent (aqueous solution) and the sorbate form the capacity unit. An experimental test rig to perform the processes of absorption and desorption was build. The high number of different sensors permit the efficiency assessment of the processes. First results show a good functioning in the power range of 1 kW, which will allow the development of a scaling method to higher power for building application. The tube bundle absorber – heat and mass exchanger - of the power unit is manufactured in three different versions. Plate tubes are used for a reference. For comparison the heat and mass exchanger has either with corrugated tubes – to increase the surface wetting - or tubes wrapped with ceramic foams. These measures are to increase both, the surface wetting of the tubes and the residence time of the sorbent in the sorbate vapour.