Abstract: To improve adsorbent's heat and mass transfer performance used for adsorption refrigeration,we prepared eight sintering compound adsorbents composed of 13X zeolite(both powders and granular type) and additives(including micron-sized iron,aluminum and expandable graphite). SEM observation as well as measurement and characterization analysis of thermal conductivity,adsorption isotherm,pore size distribution and other physical properties were carried out. The results showed that the powder zeolite with expanded graphite as additive had the best compact and the largest contact area among zeolite particles. The powder zeolite with aluminum powder as additive had the highest thermal conductivity and thermal diffusivity,increased by 100.9% and 315.6%,respectively,compared with pure component granular zeolite. The powder zeolite with iron powder had the lowest heat capacity,decreased by 33.9% compared with pure granular zeolite. The specific surface area and porosity of powder and granular zeolites were reduced due to the addition of additives. The various types of compound adsorbents studied were employed in adsorption refrigeration unit tube,and relevant performance experiments were carried out. The internal mechanisms between improvement of the adsorption refrigeration tube's performance indexes(i.e.,cycle time,cooling capacity,COP and SCP) and respective physical properties of these compound adsorbents were discussed.

Key words: micron-sized, metal additive, 13X zeolite, compound adsorbent, physical property, adsorption unit tube, performance

摘要： 为改善吸附剂用于吸附制冷的传热传质性能,以微米级铁粉、铝粉和非金属膨胀石墨为添加剂,制备了8 种不同烧结型13X 沸石分子筛(包括粉末型和颗粒型)混合吸附剂,对其进行了SEM 观察以及热导率、吸附等 温线、孔径分布等物性的测量与表征分析。结果显示,添加剂为膨胀石墨的粉末型分子筛微粒之间的紧密型最 好,接触面积最大;添加剂为铝粉的粉末型分子筛热导率和热扩散系数最高,相比纯组分颗粒型分子筛的分别 提高了100.9%和315.6%,添加剂为铁粉的粉末型分子筛比热容最低,相比纯组分颗粒型分子筛的降低了33.9%; 加入添加剂的粉末型和颗粒型分子筛的比表面积和孔隙率都有不同程度的降低,其顺序由高到低均为膨胀石墨、铝粉、铁粉。将制备的各种混合吸附剂应用于吸附制冷单元管进行实验测试,讨论分析了其循环周期、制冷量、COP 和SCP 等性能指标的改进与吸附剂物性改变之间的内在联系。

关键词: 微米级, 金属添加剂, 13X 沸石分子筛, 混合吸附剂, 物性, 吸附单元冷管, 性能