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arXiv · 2503.03257

Influence of Membrane Characteristics on Efficiency of Vacuum Membrane Distillation: a Lattice Boltzmann Study

Abstract

With increasing water scarcity, membrane distillation technology has gained widespread attention as an innovative method for seawater desalination.However,existing studies often overlook the influence of membrane characteristics on mass transfer efficiency. This study, based on the lattice Boltzmann method,proposes a model for a novel Poly(tetraethynylpyrene) membrane material to reveal the influence of membrane characteristics on the performance of vacuum membrane distillation. The model considers the factors such as porosity, tortuosity, membrane thickness, pore size, membrane surface wettability and temperature difference on the permeate flux. The results show that the permeate flux increases linearly with the porosity and decreases exponentially with the tortuosity factor. There is an optimal membrane thickness range (2μm) beyond which the permeate flux decreases exponentially. In addition, the permeate flux increases exponentially with increasing temperature difference and pore size. Further analysis of the effect of membrane surface wettability shows that permeate flux increases with increasing hydrophobicity. Finally, the feed temperature and tortuosity factor have the largest effect on permeate flux,followed by membrane thickness and, subsequently, pore size. The model can be further extended to study other configurations of membrane distillation technologies.

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BibTeXRIS

Hongxuan Zhang, Dian Gong, Yiling Zhou, Zhangrong Qin, Binghai Wen. 2025-03-05. Influence of Membrane Characteristics on Efficiency of Vacuum Membrane Distillation: a Lattice Boltzmann Study. https://arxiv.org/abs/2503.03257

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