Semi Continuous Thermochemical Reactor for Thermal Storage
Abstract
A new semi-continuous thermochemical reactor prototype for seasonal heat storage was designed, manufactured and tested. Its cross flow vertical moving bed design improves a combination of performance factors, including energy density, heat power, temperature level, reversibility, thermal losses and auxiliary consumption. Tests were conducted on a dynamically controlled air flow equipment where a calibrated instrumentation allowed measuring thermal power with temperature and humidity methods, in addition to mass gradients. After an initialization phase, the reactor works semi-continuously and heat power shows only small variations. It was measured at 415 W in both modes, and is almost proportional to air flow rate, while coefficient of performance is excellent (19 to 45). Those results were confirmed by two distinct measurement methods, based alternately on temperature and humidity. Charging phase could be performed at only 60.3°C, which is a major result because it leads to increasing system efficiency of solar thermal storage systems. Besides, it was highlighted that a better reaction real time monitoring would ease the control and increase performance, especially regarding energy density. Temperature maps were installed on both sides of the reacting bed. Results suggest that beyond the qualitative results, they could be used to calculate a real time distribution of composite hydration level.