Membrane distillation is a new membrane separation process which is developed in recent years. It is a membrane technology which uses hydrophobic microporous membrane to separate aqueous solution containing non-volatile solute. The membrane distillation process is to use the factory waste heat, waste heat or steam to heat the raw material to a certain temperature, through the raw material pump, into the membrane distillation component, the raw material liquid on both sides of the film to produce steam pressure difference, a large number of micro holes on the surface of the film can allow the evaporation of water vapor through the membrane hole, into the other side of the membrane component, the use of vacuum system to draw out. After volatilizing a large amount of water vapor, the raw material liquid is concentrated, and the volatilized steam uses the heat pump to recover the heat and return to reheat the raw material liquid to reduce the energy consumption of the entire system.