| 摘要: |
| 为解决传统填料塔式溶液再生方法热效率低、受环境影响大、存在飘液等问题，本文提出一种基于真空膜蒸馏的溶液再生方法。通过实验和模拟研究了溶液温度、流速、质量分数以及系统真空度对膜通量、热效率、跨膜传质系数、截留率的影响。结果表明：膜通量随溶液温度、流速、系统真空度的升高而增加，随溶液质量分数的升高而急剧下降，膜通量实验值与模拟值的偏差在±10%以内；热效率随溶液温度和系统真空度的升高而增加并最终趋于恒定，随溶液流速和质量分数的升高而降低；跨膜传质系数随溶液温度、流速、系统真空度的升高而增大，随溶液质量分数的升高而减小。在实验中，当溶液温度为80 ℃，流速为1.0 m/s，质量分数为20%，系统真空度为93 kPa时，膜通量达到最大，为7.18 kg/(m2?h)，即使在40%的高质量分数下，膜通量仍可达到1 kg/(m2?h)，热效率普遍高于80%，溶液流速为0.6 m/s时各性能参数均可达到较高水平。 |
| 关键词: 溶液再生 除湿空调 真空膜蒸馏 膜通量 传热传质 |
| DOI： |
| 投稿时间：2021-03-19 修订日期：2021-04-19
|
| 基金项目:国家自然科学基金（51520105009）和江苏省重点研发计划(BE2018118)项目资助。 |
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| Experimental Study on Liquid Desiccant Regeneration in Air Conditioning System by Vacuum Membrane Distillation |
| Wang Jianwei,Zhang Xiaosong,Sun Bo,Zhou Junming |
| (School of Energy and Environment, Southeast University) |
| Abstract: |
| To address the issues of lower thermal efficiency, susceptibility to environmental influences, and floating liquid desiccant in traditional liquid desiccant regeneration methods using packed towers, this article proposes a liquid desiccant regeneration method based on vacuum membrane distillation. The effects of liquid desiccant temperature, flow rate, mass fraction, and the vacuum degree of the system on the membrane flux, thermal efficiency, transmembrane mass transfer coefficient, and rejection rate were studied through experiments and simulations. The results show that the membrane flux increases with an increase in the liquid desiccant temperature, flow rate, and vacuum degree of the system and decreases sharply with an increase in the liquid desiccant mass fraction. The deviation of the experimental membrane flux from the simulated ones are within ±10%. The thermal efficiency increases and tends to be constant with the increase in liquid desiccant temperature and the vacuum degree of the system and decreases with an increase in the liquid desiccant flow rate and mass fraction. The transmembrane mass transfer coefficient increases with the increase in liquid desiccant temperature, flow rate, and system vacuum, and decreases with an increase in the liquid desiccant mass fraction. In the experiment, when the liquid desiccant temperature, the flow rate and the mass fraction are 80 ℃, 1.0 m/s and 20%, respectively, the vacuum degree of the system is 93 kPa, and the membrane flux reaches the maximum, which is 7.18 kg/(m2?h). Even at a high mass fraction of 40%, the membrane flux can still reach 1 kg/(m2?h). The thermal efficiency is generally higher than 80%. When the solution flow rate is 0.6 m/s, all performance parameters can reach a higher level. |
| Key words: liquid desiccant regeneration liquid desiccant air conditioning vacuum membrane distillation membrane flux heat and mass transfer |
