Mechanical vapor recompression system and mechanical vapor recompression method based on system

The invention discloses a mechanical vapor recompression system and a mechanical vapor recompression method based on the system. The system comprises an evaporative condenser, a heat exchanger, a compressor and a vapor generator, wherein the evaporative condenser connects the heat exchanger, the compressor connects the evaporative condenser and the heat exchanger, and the vapor generator is arranged between the heat exchanger and the compressor; the evaporative condenser comprises a first vapor outlet, a first vapor inlet and a first water outlet; the heat exchanger comprises a second vapor outlet, a second vapor inlet and a second water inlet; the first vapor outlet connects the second vapor inlet, the first water outlet connects the second water inlet, and the second vapor outlet connects the first vapor inlet. According to the invention, heat in material vapor is transferred to condensate water through the heat exchanger to generate water vapor and the water vapor which is compressed serves as a heat source to heat material solution to evaporate, so that utilization of secondary vapor waste heat is realized. The system and method disclosed by the invention have advantages of being strong in adaptability, high in energy utilization and high in safety.