Abstract: Compared with conventional separation facilities，novel membrane contactors will play a more and more important role in waste treatment in the near future. The advantages in separation include wider operation range，high separation efficiency，independent flow between liquid and gas，linear scale-up and compact structure，etc. Typical gas/liquid separation processes，such as membrane adsorption，membrane distillation and membrane structured packing in waste treatment and solvent purification are discussed in detail. The performance of different membrane contactors and characteristics of their materials and module structures are also studied with mass transfer analysis.