As one of the state-of-art desalination technologies, membrane distillation (MD) has been widely studied in recent years. In order to better control the performance of the MD, a new model that can predict the membrane surface temperatures, permeate flux as well as salinity variation with the operating time has been proposed in this study. Using the model, impacts of operating parameters such as bulk temperature, flow rate, different membrane materials and feed salinity on the permeate flux as well as the efficiency of driving force were simulated. The results of the simulations indicate that feed temperature, feed flow rate and membrane pore size have the most significant influence on the permeate flux. However, the feed and permeate flow rates have the highest impacts on the temperature polarization coefficient (TPC) which has the highest value of 0.68 under certain conditions. Besides, the simulations predicted that the water recovery from the MD for the seawater and the desalination brine at the saturation point of NaCl to be 86.8 % and 72.1 %, respectively. Finally, the salinity variations with operating time were also simulated and the new model would be vital for the salinity control in desalination processes such as membrane distillation crystallization.

作为最先进的海水淡化技术之一，膜蒸馏（MD）近年来得到了广泛的研究。为了更好地控制 MD 的性能，本研究提出了一种可以预测膜表面温度、渗透通量以及盐度随运行时间变化的新模型。使用该模型，模拟了操作参数（如体积温度、流速、不同的膜材料和进水盐度）对渗透通量以及驱动力效率的影响。模拟结果表明，进料温度、进料流速和膜孔径对渗透通量的影响最为显着。然而，进水和渗透流量对温度极化系数 (TPC) 的影响最大，在某些条件下最高值为 0.68。此外，模拟预测海水和淡化盐水在 NaCl 饱和点从 MD 的水回收率分别为 86.8 % 和 72.1 %。最后，还模拟了盐度随运行时间的变化，新模型对于膜蒸馏结晶等海水淡化过程中的盐度控制至关重要。