Abstract Improving the efficiency and sustainability of water treatment technologies is crucial to reduce energy consumption and environmental pollution. Solar-driven devices have the potential to supply off-grid areas with freshwater through a sustainable approach. Passive desalination driven by solar thermal energy has the additional advantage to require only inexpensive materials and easily maintainable components. The bottleneck to the widespread diffusion of such solar passive desalination technologies is their lower productivity with respect to active ones. A completely passive, multi-effect membrane distillation device with an efficient use of solar energy and thus a remarkable enhancement in distillate productivity has been recently proposed. The improved performance of this distillation device comes from the efficient exploitation of low-temperature thermal energy to drive multiple distillation processes. In this work, we analyze the proposed distillation technology by a more in-depth thermodynamic detail, considering a Second Law analysis. We then report a detailed exergy analysis, which allows to get insights on the production of irreversibilities in each component of the assembly. These calculations provide guidelines for the possible optimization of the device, since simple changes in the original configuration may easily yield up to a 46% increase in the Second Law efficiency.

中文翻译：

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基于被动多效膜蒸馏的太阳能海水淡化系统火用分析

摘要 提高水处理技术的效率和可持续性对于减少能源消耗和环境污染至关重要。太阳能驱动的设备有可能通过可持续的方法为离网地区提供淡水。由太阳能热能驱动的被动海水淡化具有额外的优势，即只需要廉价的材料和易于维护的组件。这种太阳能被动海水淡化技术广泛推广的瓶颈在于它们相对于主动海水淡化技术的生产率较低。最近提出了一种完全被动、多效的膜蒸馏装置，可有效利用太阳能，从而显着提高馏出物生产率。这种蒸馏装置的改进性能来自于有效利用低温热能来驱动多个蒸馏过程。在这项工作中，我们考虑到第二定律分析，通过更深入的热力学细节分析了所提出的蒸馏技术。然后，我们报告了详细的火用分析，从而可以深入了解组件每个组件中不可逆性的产生。这些计算为设备的可能优化提供了指导，因为对原始配置的简单更改很容易使第二定律效率提高 46%。然后，我们报告了详细的火用分析，从而可以深入了解组件每个组件中不可逆性的产生。这些计算为设备的可能优化提供了指导，因为对原始配置的简单更改很容易使第二定律效率提高 46%。然后，我们报告了详细的火用分析，从而可以深入了解组件每个组件中不可逆性的产生。这些计算为设备的可能优化提供了指导，因为对原始配置的简单更改很容易使第二定律效率提高 46%。