Novel low-temperature multi-effect seawater desalination evaporator

The invention relates to a novel low-temperature multi-effect seawater desalination evaporator in which multi-effect evaporators are arranged up and down. The top end of each evaporation chamber is provided with a water distribution device; a water inlet end of the water distribution device of the uppermost evaporation chamber can be or not be provided with a preheater; a heat exchange tube is arranged in each evaporation chamber; the front and back ends of each heat exchange tube are respectively provided with a tube plate; the outer side of each tube plate is provided with a freshwater tank; the lower side of each heat exchange tube is provided with a concentrated water tank; every two adjacent upper and lower freshwater tanks are connected through a J-shaped inter-effect freshwater connecting tube; the concentrated water tank on the upper layer is communicated with the upper side of the water distribution device of the evaporator on the lower layer through a J-shaped inter-effect freshwater connecting tube; and secondary vapor generated by the upper evaporation chamber enters the heat exchange tube of the lower evaporation chamber through inter-effect vapor connecting tubes positioned on two sides of the back side of an evaporator tube bank to be used as an evaporation heat source. The novel low-temperature multi-effect seawater desalination evaporator can enhance the seawater concentration ratio, does not need any inter-effect pump, lowers the energy consumption for seawater desalination, and ensures that influent water of the multi-effect evaporation chamber with higher evaporation temperature is raw seawater, thereby lowering the scaling risk.