Experimental Study On The Thermal Conductivity And Permeability Of Compound Adsorbent Of Different Matrix Materials

Adsorption refrigeration is a energy saving and environmental benignrefrigeration technology, it has a great development potential. However, becauseof the low efficiency of refrigeration, comparing with other refrigeration, it is stilllacking of competitive power. There are many methods to develop the efficiencyof adsorption refrigeration, one of the effective ways is strengthen the heat andmass transfer of adsorbent, however, conductivity and permeability are twoimportant parameters to characterize the adsorbent’s heat and mass transferperformance. So this article studied on the conductivity and permeability ofadsorbent of different matrix materials be aimed at finding the relationshipbetween the value of the conductivity and permeability and temperature、pressingdirection、proportion of mixture and density changes in the compound adsorbent,and the find out the optimized proportion of mixture for the compound adsorbent.The main work and conclusions of this article are as follows：（1）The compound adsorbent of sawdust matrix material was prepared bycarbonization and activation method,and analyzed the influence of carbonizationand activation temperature on the structure and internal composition of adsorbent.The experiment result showed that： the best carbonization and activationtemperature is60℃.（2）The thermal conductivities of the disk、plate samples of Cacl2/ENG andnew adsorbents were tested by Nano flash LFA447. The experiment results showthat：the thermal conductivity of samples is enhanced with increasing density anddecreasing mass ratio; at the same time, the thermal conductivity of plate samplesare higher than disk samples, which proved that the thermal conductivity isanisotropic; the thermal conductivity of Cacl2/ENG samples are s over2.7-3.5 times higher than new samples; In all the test samples,the maximum thermalconductivity of Cacl2/ENG disk samples can reach12.24W/(m·K) and platesamples can reach13.37W/(m·K)；In all the test samples,the maximum thermalconductivity of new adsorbent disk samples can reach3.75W/(m·K) and platesamples can reach4.25W/(m·K).(3)The bench of permeability measurement was designed and processedaccording to the Ergun model.(4) The permeability of the disk、plate samples of Cacl2/ENG and disksamples were tested, The experiment results show that：the permeability of disk、plate samples of Cacl2/ENG and disk samples of new adsorbent is enhanced withdecreasing density and increasing mass ratio; the permeability of disk samples ofCacl2/ENG are over10times higher than disk samples, which proved that thepermeability is anisotropic; the permeability of disk samples of new adsorbentranges from8.46×1014to7.230×1012m2,and they are over2times higher thandisk samples of Cacl2/ENG.