Experimental study of CaO/Ca(OH)2 in a fixed-bed reactor for thermochemical heat storage

Abstract

The CaO/Ca(OH)2 thermochemical heat storage system is a very promising method to realize solar thermal energy utilization and industrial waste heat recycling. In this study, a CaO/Ca(OH)2 test-bed is setup to investigate the heat storage and release processes. In the heat storage process of pure Ca(OH)2, a higher dehydration temperature results in a faster heat storage speed. In addition, the heat storage process of Li-doped Ca(OH)2 can obtain a faster heat storage speed and produce more thermal energy than that of pure Ca(OH)2. The results of the experiment show that the air can seriously affect the heat release process in a fixed-bed test. Therefore, the method of pumping out the air is used in this study to improve the heat release process. According to the results of the heat release experiment, a lower initial sample temperature can lead to a higher extent of the dehydration reaction. Furthermore, a higher vapor pressure obviously improves the heat release capacity.