FILTRATION APPARATUS AND FILTERING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a filtration apparatus which can cope with original water having the possibility that an impurity mingles in and can restrain the increase of the pressure loss owing to the inflow of the impurity and from which the impurity can be discharged easily and to provide a filtering method. SOLUTION: This filtration apparatus is constituted so that a filter medium is packed in a filtration tank, a screen is arranged in each of the upper and lower parts of a filter medium layer and a treated water discharge pipe is arranged in each of the upper and lower parts of the filtration tank. The original water supply space which is communicated with an original water inflow pipe and partitioned by the screen is formed in the filtration tank and a discharge port to be opened/closed freely is arranged in the original water supply space. COPYRIGHT: (C)2004,JPO