关键词: 膜蒸馏, 膜, 传热, 优化, 脱盐

Abstract: Membrane distillation is a new thermally-driven separation process，in which vapor molecules driven by partial pressure gradient across the membrane are able to transfer through the pores and condense outside the membrane. In this paper，the heat and mass transport mechanisms and four mainly used membrane configurations，i.e.，direct contact membrane distillation，air gap membrane distillation，sweeping gas membrane distillation and vacuum membrane distillation are described. New research progress is reviewed，including influence of membrane operation and characteristic parameters，preparation of membrane with high performance，improvement in process and operation parameters aiming at membrane fouling，enhancement of membrane distillation process by optimizing energy utilization and modules. In addition，applications in desalination and water purification，juice concentrate and alcohol fermentation，separation of chemical volatile organic compounds as well as toxic waste water treatment are summarized. Finally，the obstacles faced by membrane distillation：combined influence of pertinent parameters，commercialization of membrane materials，membrane module design and thermal efficiency of the process are presented. To achieve its further application，it is necessary to strengthen energy studies，to develop more commercialized membrane materials，to focus more on other membrane distillation configurations，and to analyze and optimize the process systematically.

Key words: membrane distillation, membranes, heat transfer, optimization, desalination