新型复合吸附剂的性能研究与模拟分析

Study the characteristic of a new composite adsorbent and the simulation of a simple adsorption process

介绍了一种硅胶与氯化锂复合的新型复合吸附剂,并结合工业化生产设计了制备容器,在不影响复合剂性能的情况下尝试进行大规模制备。在恒温恒湿箱中,设定温度为30℃、湿度为95%,对复合吸附剂进行了动态吸水吸附性能测试。实验表明,这类吸附剂的吸水性能大大优于普通硅胶吸附剂。采用吸附等容法测定了复合吸附剂–甲醇的吸附平衡曲线,用Dubinin-Astakhov(D-A)方程拟合吸附平衡公式,得出了公式中重要的参数,并且模拟得出一系列吸附平衡曲线。计算了不同工质对同一工况下的COP(制冷效率)与SCC(单位质量制冷量)。结果表明,复合吸附剂的运用提高了COP与SCC。由于甲醇的蒸发潜热较低,因此SCC较小。但是蒸发温度较低,可以得到制冷工况。并且工作压力大,提高了机器运行的稳定性。为了分析吸附过程的传热传质过程,对实验中的吸附动态过程进行了数学建模,并且进行了模拟。模拟结果和实验结果趋势较为吻合。

This paper presents a new composite adsorbent （lithium chloride confined to silica gel）. The chamber for preparation the adsorbent was designed for industrialized production process. The kinetics of the water adsorption on the composite adsorbent was tested in the constant temperature/humidity equipment which was set at 303 K and 95% respectively. The results showed that the new composite adsorbent has a better adsorption capacity than the pure silica gel. The adsorption equilibrium of methanol on composite adsorbent was measured by the sorption isosteric method. Dubinin-Astakhov （D-A） equation was used to fit the experiments data. COP and SCC of different working pairs are caculated. The results showed that the using of composite adsorbent can improve COP and SCC. Though the methanol has a low SCC due to the low evaporation latent heat, it has a larger COP and the low evaporation temperature which can be used in the ice making. To analysis the heat transfer process and demonstrated the accuration of the parameters derived, a simulation of a simple asdorption process was done.