Back Fresh Method Using Influent Water Head and Filter Apparatus Employing the Same

摘要

PURPOSE: A filtration method which carries out filtration and back washing side by side in one or a small number of filtration cells even in the state that filtration is proceeded in a plurality of filtration cells, and a filtration apparatus employing the filtration method are provided. CONSTITUTION: The filtration apparatus is characterized in that two or more of filtration cells(1,1a) in which granular filtering media filled filter beds(2,2a) are installed, and at the lower part of which a supporting layer(3) supporting the filter beds(2,2a) is installed are piled up one on another, inlets and outlets of raw water and polluted water are installed at the filtration cells(1,1a), the filtration cells(1,1a) are connected to a lower water collection part so that filtered water is transported therebetween, a raw water inlet channel(11) and a polluted water outlet channel(21) are connected to the inlets and outlets of the raw water and the polluted water, and channel control means are installed at the raw water inlet channel(11) and the polluted water outlet channel(21). The filtration apparatus is characterized in that an agitating means such as rake and scraper capable of removing and stirring up a consolidation layer of solids formed on the surface of the filter beds(2,2a), or stirring up a surface layer part of the filter beds(2,2a) is installed at the upper part of the granular filtering media filled filter beds(2,2a), wherein the agitating means is an air blowing pipe from which air is emitted, or a nozzle from which water is ejected.