Dynamic characteristics of permeability of the using calcium chloride/expanded graphite composites used for a chemical heat pump

摘要

Dynamic characteristics of the permeability of the calcium chloride/expanded graphite composites using for a chemical heat pump have been experimentally investigated. The void fraction of the composites were changed in three steps; 0.64, 0.65 and 0.66. The time-dependency of the permeability and of the hydration reaction rate was calculated from the pressure loss of the composites and the vapor mass that flows through the composites while hydration reaction occurs under a constant inlet pressure. From the results, it was found that the permeability decreases with the hydration reaction, that the decrease rate increases as the initial void fraction decreases. This decrease of the permeability of the composites occurs due to the hydration of calcium chloride. As density of CaCb in composites is larger as the void fraction is small, it is considered that the decrease of permeability becomes larger in the case of high void fraction.