Water molecules in wastewater diffuse from one side of the membrane to the other side by using the vapor pressure difference between the cold and hot sides of the water, while other components in wastewater are blocked on the hot side, thus realizing the separation of pollutants in wastewater. Water requirements are: no suspended solids of 20μm, pH 2-11, and TDS range 0- 160,000 ppm. The pretreated wastewater is heated to a temperature of 45-65℃ and sent to the membrane module. A vacuum pump is used to evacuate the cold side of the membrane module to form a vapor pressure difference between the cold and hot sides of the membrane module, and push water molecules through the membrane module. Then the latent heat of vaporization in the water vapor is recovered through the heat exchanger to reduce the energy consumption of the finishing system. When treating high-concentration sewage, this technology can be combined with RO systems to improve the treatment efficiency of the entire system and reduce concentrated water emissions after RO treatment by improving the overall water recovery rate.