Wastewater treatment flue evaporator capable of preventing wall surface ash deposition

The invention provides a wastewater treatment flue evaporator capable of preventing wall surface ash deposition. The wastewater treatment flue evaporator capable of preventing wall surface ash deposition comprises a flue evaporator internally provided with wastewater atomization devices, and is characterized in that purging tuyeres located in different areas are distributed in a height direction of an evaporator cylinder wall surface of the flue evaporator, the n purging tuyeres of each area are arranged in the circumference of the evaporator cylinder wall surface, and each purging tuyere is in cooperation with the evaporator cylinder wall surface to divide a purging wind source into two parts of inner side wind and outer side wind which blow into the flue evaporator, wherein the inner side wind flows out through the centers of the purging tuyeres to prevent adhesion of unevaporated liquid drops on the evaporator cylinder wall surface; and the outer side wind forms a gas protection film which covers the evapo