Abstract Humidification-dehumidification desalination systems are best suited for small-scale and off-grid applications. The primary drawback of humidification-dehumidification systems is their low thermal performance. Thermodynamic balancing of the heat and mass exchange processes between the humidifier and dehumidifier can substantially improve their performance. The optimal thermal design is still needed; thus, the present study mostly focuses on the design of a thermodynamically-balanced system both with and without extractions. This study starts with the implementation of the temperature-enthalpy diagram model to investigate the effect of system enthalpy pinch and minimum and maximum saltwater temperatures on the performance of zero-, single-, and double-extraction systems. After that, design details are investigated to determine the size of the humidifier and dehumidifier under various conditions and power requirements. It is found that the system performance increases as a function of the heat and mass transfer areas (energy effectiveness) of the humidifier and dehumidifier. The systems’ performance is represented by the gained output ratio, recovery ratio, energy effectiveness, and enthalpy pinch. The gained output ratio of the single- and double-extraction systems is better than that of the zero-extraction system by a factor of 91% and 112%, respectively. The areas of the single- and double-extraction systems are larger than that of the zero extraction system by a factor of about 51% and 80%, respectively.

中文翻译：

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一种确定热力学平衡加湿-除湿脱盐系统尺寸的设计程序

摘要 加湿-除湿海水淡化系统最适合小规模和离网应用。加湿-除湿系统的主要缺点是它们的热性能低。加湿器和除湿器之间的热量和质量交换过程的热力学平衡可以显着提高它们的性能。仍然需要优化的热设计；因此，目前的研究主要集中在有和没有抽气的热力学平衡系统的设计上。本研究从实施温度-焓图模型开始，以研究系统焓夹点以及最低和最高盐水温度对零提取、单提取和双提取系统性能的影响。之后，研究设计细节以确定在各种条件和功率要求下加湿器和除湿器的尺寸。发现系统性能作为加湿器和除湿器的传热和传质面积（能量效率）的函数而增加。系统的性能由获得的输出比、回收率、能量效率和焓收缩来表示。单萃取和双萃取系统的增益输出比分别优于零萃取系统的 91% 和 112%。单抽和双抽系统的面积比零抽系统的面积分别大了约 51% 和 80%。发现系统性能作为加湿器和除湿器的传热和传质面积（能量效率）的函数而增加。系统的性能由获得的输出比、回收率、能量效率和焓收缩来表示。单萃取和双萃取系统的增益输出比分别优于零萃取系统的 91% 和 112%。单抽和双抽系统的面积比零抽系统的面积分别大了约 51% 和 80%。发现系统性能作为加湿器和除湿器的传热和传质面积（能量效率）的函数而增加。系统的性能由获得的输出比、回收率、能量效率和焓收缩来表示。单萃取和双萃取系统的增益输出比分别优于零萃取系统的 91% 和 112%。单抽和双抽系统的面积比零抽系统的面积分别大了约 51% 和 80%。单萃取和双萃取系统的增益输出比分别优于零萃取系统的 91% 和 112%。单抽和双抽系统的面积比零抽系统的面积分别大了约 51% 和 80%。单萃取和双萃取系统的增益输出比分别优于零萃取系统的 91% 和 112%。单抽和双抽系统的面积比零抽系统的面积分别大了约 51% 和 80%。