Method for recycling liquefied flash steam to realize energy conservation

The invention relates to a method for recycling liquefied flash steam to realize energy conservation, and belongs to an energy-saving method in the sugar production process using corn starch. The method comprises the following steps: using a water heater I to perform injection heating on starch milk to reach the temperature of 107 DEG C by virtue of starch milk heated by a heat exchanger and fresh steam, allowing the heated vapor liquid to enter a flash evaporator I for separating, heating the liquid to the temperature of 145 DEG C by a water heater II, allowing the heated vapor liquid to enter a flash evaporator II, mixing the vapor subjected to flash evaporation twice, introducing the mixed vapor into an evaporation heater by a fan so as to perform heating evaporation on sugar liquid, allowing the heated vapor liquid to enter a vapor-liquid separator for performing vapor-liquid separation, condensing 70%-80% of the separated non-condensable gases in a surface condenser, allowing the rest non-condensable gases to enter the heat exchanger, heating the incoming starch milk, and using a vacuum pump to extract the non-condensable vapor condensed by the surface condenser and the heat exchanger. The method disclosed by the invention has the advantages that the flash waste heat is recovered, the temperature of the low-temperature starch milk is increased, the steam consumption while heating by the water heaters is saved, the heat is recycled, and the steam is saved.