化学吸附制冷用氯化锶复合吸附剂的制冷性能

Refrigeration performance of strontium chloride composite adsorbents for chemisorption refrigeration

对以SrCl2、活性炭为吸附剂,NH3为制冷剂所组成的吸附式制冷工质对的吸附性能进行了研究。拟解决SrCl2吸附剂颗粒强度不高、长期使用后易出现膨胀粉化、吸附床传热传质性能下降等问题,将SrCl2分别与活性炭、CaSO4按质量比4∶1复配,进行吸附制冷性能实验。并对SrCl2的吸附机理及CaSO4的胶凝作用进行了探讨。实验结果表明:温度是过程的控制因素,在100℃时,SrCl2/活性炭、SrCl2/CaSO4复合吸附剂的单位脱胶凝剂基吸附剂制冷量分别是SrCl2的2·1倍和1·4倍。对吸附剂比表面积及孔结构进行表征,结果显示:SrCl2/CaSO4复合吸附剂的比表面积和孔结构保持良好;SrCl2/活性炭复合吸附剂的比表面积和孔容明显增大,孔结构得到了改善。

A study on the adsorption characteristics of the adsorption refrigeration working pairs using strontium chloride and activated carbon as adsorbents and ammonia as refrigerant was performed. The strontium chloride adsorbent particles had a lower strength which would cause them to swell and smash after a period of working time. In addition, the heat and mass transfer characteristics of the adsorption bed would deteriorate. To solve these problems, activated carbon and calcium sulfate were added and mixed to the strontium chloride with a mass ratio 20 %, separately. The adsorption mechanism of strontium chloride and gelation of calcium sulfate were also discussed. The adsorption refrigeration experimental results showed that the control factor was temperature. For example, the refrigeration capacity of the unit adsorbent of strontium chloride/activated carbon and strontium chloride/calcium sulfate were 2.1 times and 1.4 times higher than that of strontium chloride at 100℃, respectively. BET （Brunauer-Emmett- Teller） specific surface area and pore structure of adsorbents were examined. The results showed that the BET specific surface area and pore structure of SrCl2/CaSO4 were kept at the same level, and the BET specific surface area of SrCl2/activated carbon increased greatly and its pore structure was improved.