JPS5925609B

PURPOSE:To exactly remove dust from water way by a cleaning method in which an annular screen cylinder formed by connecting a large number of cagelike metal net panels of an involute shape with an endless chain is moved a circulating manner. CONSTITUTION:Water to be treated, coming from the inlet 14 of an apparatus 1, enters into an annular screen cylinder 8 and then goes out from the inside to the outside of a cagelike metal net panel 7 located on the lower side after being directed dividedly in both directions, during which period dust is arrested by the cagelike metal net panel 7 and the water becomes treated water. The annular screen cylinder 8 is circulated at a moving rate of 3-4m/min, the cagelike metal net panel 7 bearing dust arrested is gradually lifted upwards on the surface of water and moves around a sprocket 4, and during the period, jet water from a back washing nozzle 9 cleans the metal net and dust with jet water in the metal net is flowed into a trough 11. The dust collected in the trough 11 is delivered with water supplied to the trough to the outside of the apparatus and then collected in a dust storage tank. And, only the water is flowed to water way.