Venturi is under the grille of the lacquer room. The mist - rich air from the painting area was guided by Venturi under the action of the exhaust fan. In the meantime, the washing water is atomized, and the paint particles that diffuse in the exhaust are wetted by water. The water pump is discharged from the system slot to make it act as the washing water. The washing water passes through the water distribution device, and flows to the venturi throat with a uniform and uninterrupted water film through the water flowing plate. Because the air velocity Yinwenshi throat section narrows greatly increased, and the drop in the nozzle back, so the water - air mixture in the edge strength and swirl atomization. In the decompression chamber, the flow of exhaust gas is changed through the baffle plate. Here, the separated water and the condensed paint particles are directed to the system slot. The clean exhaust gas is pumped by the exhaust fan, and passes through a heat recovery equipment and then is discharged to the outside through the roof.