JM-multi effect Falling Film Evaporator adopts falling film, which can combine single-effect, double-effect, triple-effect, four-effect, five-effect, six-effect vacuum evaporation system according to the character of the condensate and the users’ requirements. Forced circulation evaporator, crystallizing evaporator and the falling film evaporator could be used at the same time according to the character of the material, which applies to vaporization and crystallization technics of high-viscosity, easy-scaling, crystallizing material. The vaporization device is equipped with steam jet heat pump, which minimizes steam consumption. The falling film evaporator has the advantage of high heat transfer efficiency, small temperature difference, low boiling point elevation, less power requirement, short heating time, and has the character of high concentration ratio(1:10), wide range of use, short time of stay, constant production at the same time. The gas-liquid separation of the evaporator adopts whirlwind separator, which has the advantage of big processing area, fully separation of gas-liquid, low entrainment, low condensate water C0D. The falling film evaporator is not only particularly suitable for evaporation of thermal sensitive material, but for material concentration of high viscosity, high discharge condensation, corrosiveness and huge evaporation amount.