NOVELTY - The device comprises a case frame (1) made of plastic material. An upper side of the case frame is provided with a condensing film (2). A lower side of the case frame is provided with a composition evaporation plate (3). The case frame, the condensing film and the composition evaporation plate form a closed case body. An upper end of the closed case body is provided with a sewage distribution tank (4). The sewage distribution tank is connected with a sewage inlet port (5). A lower end of the closed case body is provided with a separating plate.    USE - The device is useful for treating high difficulty wastewater using solar energy.    ADVANTAGE - The device allows easy and rapid treatment of wastewater with high efficiency and reduced energy consumption, and has simple structure.    DETAILED DESCRIPTION - The device comprises a case frame (1) made of plastic material. An upper side of the case frame is provided with a condensing film (2). A lower side of the case frame is provided with a composition evaporation plate (3). The case frame, the condensing film and the composition evaporation plate form a closed case body. An upper end of the closed case body is provided with a sewage distribution tank (4). The sewage distribution tank is connected with a sewage inlet port (5). A lower end of the closed case body is provided with a separating plate. An upper side of the separating plate is formed with a condensation water collecting tank. The condensation water collecting tank is connected with a condensation water discharge port. A lower side of the separating plate is formed with a concentrated liquid collecting tank. The concentrated liquid collecting tank is connected with a concentrated liquid discharge port. The composition evaporation plate is composed of a plastic substrate, black chemical fiber non-woven fabric and foamed plastic insulation board. The black chemical fiber non-woven fabric is placed at an upper side of the plastic substrate while the foamed plastic insulation board is placed at a lower side of the plastic substrate.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a device for treating wastewater.    Case frame (1)    Condensing film (2)    Composition evaporation plate (3)    Sewage distribution tank (4)    Sewage inlet port. (5)