凹土-氯化钙复合吸附剂的制冷性能

Adsorption Refrigeration Characteristic of Attapulgite Based Calcium Chloride Composite Adsorbents

采用凹凸棒粘土和氯化钙为主要原料，用溶解．混合法制备了复合吸附剂；采用正压重量法测量了复合吸附剂对氨的吸附等温线；并测定了吸附剂．氨工质对的制冷特性。结果表明：吸附温度30℃下，复合吸附剂对氨的平衡吸附量为1．1kg／kg，与氯化钙对氨的平衡吸附量相当。在装填密度为600kg／m3，吸附温度为30℃、蒸发压力为0．25MPa、解吸温度为300℃条件下，对氨的吸附量达到0．89-0．92kg／kg，循环吸附量为0．55～0．58kg／kg，是纯氯化钙的1．7倍；复合吸附剂一氨工质对制冷量可达761．84kJ／kg，比氯化钙-氨工质对提高T70％。而且，复合吸附剂具有良好的吸附解吸稳定性能。

The composite absorbent is mainly consisted of attapulgite and CaCl2 as the resources, which were prepared by the dissolution-mixed method, and the content of attapulgite in composite absorbent is 10%. Adsorption isotherms of ammonia onabsorbents were determined by positive gravimetric method. Adsorption-desorption cycle performance and cooling characteristics of composite absorbent -ammonia working pairs was evaluated by self-made adsorption-desorption measuring device. Experimentalresults show that the equilibrium capacity of ammonia on the composite absorbent is up to 1.1kg/kg at 30℃, which is equal to that of CaC12. The conditions of loading density 600kg/m3, adsorption temperature 30℃ ammonia evaporation pressure 0.25 MPa,desorption temperature 300℃, adsorption capacity of ammonia in the composite absorbent and its cyclic adsorption capacity is 0.89-0.92 kg/kg and 0.55-0.58 kg/kg, respectively, which is 1.7 times than that of CaC12-ammonia working pairs. The coolingcapacity is up to 761.84kJ/kg, which is increased by 70% compared to CaCl2 ammonia. What＇s more, composite absorbent has excellent adsorption and desorption stability.