PROBLEM TO BE SOLVED: To obtain an air flow clarifying apparatus which is compact and easy to handle.SOLUTION: A bent flow passage 16, in which gas changes its direction to a lateral width direction and flows in a horizontal direction, is provided in a flow passage pipe 11 of the air flow clarifying apparatus. The inside of the bent flow passage is partitioned to two or more divided channels 18 by two or more bent partition plates 17. On a downstream side of the bent flow passage, a weir 15 with an upheaved bottom floor 14 is provided. A top end part 19 located on the downstream side of each of the bent partition plates is arranged on an upstream side of the weir 15. At the top end part of each of the bent partition plates, a ridge 22 projected in a direction facing a curvature center 20 of the bent flow passage is provided to form a vertical groove 23 continuing in a vertical direction at a boundary line between the ridge and an internal wall surface 21 of each of the bent partition plates. The bottom floor 14f on an upper stream side of the bent flow passage is made to be lower than the weir, and thereby, liquid can be made to flow from the weir to the bottom floor on the upper stream side. A drain pipe 24, for removing the liquid that hits on the ridge at the top end part of each of the bent partition plates, drops and gathers, is provided at the bottom floor on the upper stream side, which is lower than the weir.
