Experimental determination of specific heat and thermal conductivity of clay + additives-CaCl2 composite desiccant

摘要

The use of solid desiccants for water vapour adsorption requires higher regeneration temperature and liquid desiccants alone requires continuous recirculation. To avoid these disadvantages, the inert material like clay is used as liquid desiccant carrier in a packed bed desiccant system. The thermo-physical properties of desiccant carriers have a direct influence on the performance of desiccant bed. In this study, variation of thermo-physical properties of burnt clay with and without impregnation of CaCl2 and the effect of additives (saw dust and horse dung) at various percentages is investigated. Cylindrical clay samples are made and the thermal properties determined. Rapid transient measurement technique is used for the measurement of thermal diffusivity. Specific heat is determined by energy balance. The addition of saw dust and horse dung increased the porosity of burnt samples. Specific heat is seen to increase with addition of additives. The CaCl2 is retained in the pores of burnt clay pellets which may facilitate the dehumidification of moist air.