| 摘要 |
<p>It is an object of the present invention to provide a filtration system capable of achieving both uniform backwashing of floating filter media layer and efficient backwashing with low cost. The filtration system of the present invention comprises; a first filtration tank having a first floating filter media layer, a first upper screen with a first aperture ratio, the first upper screen being disposed over the first floating filter media layer and supporting the floating filter media, a first inlet for water to be treated disposed below the first floating filter media layer, a first backwash water supply source located over the first upper screen, and a first backwash water outlet means disposed below the first floating filter media layer; and a second filtration tank having a second floating filter media layer, a second upper screen with a second aperture ratio, the second upper screen being disposed over the second floating filter media layer and supporting the floating filter media, a second inlet for water to be treated disposed below the second floating filter media layer, an inflow blocking mechanism capable of blocking inflow of water to be treated through the second inlet for water to be treated, a second backwash water supply source located over the second upper screen, and a second backwash water outlet means disposed below the second floating filter media layer, in which the first aperture ratio is smaller than the second aperture ratio.</p> |
