| 摘要 |
<p>PURPOSE:To perform efficient aerobic biological treatment by providing a packing layer, a packed layer wherein packings and solid particles are mixed and a supporting layer successively from the upper part in a treating tank, providing a collecting device for treated water and an air introducing device on the side below the supporting layer and introducing waste water from the upper part. CONSTITUTION:A discharge port 15 for treated water and an air piping 7 for aeration are provided in the lowermost end part in a treating tank 1, and devices 5 for collecting water and introducing air are laid on the bottom surface. A supporting layer 4 is formed thereon and a mixed packed layer 3 consisting of a uniform mixture of fine solid particles and coarse packings is formed thereon. The solid particles having the grain sizes ranging to 0.2-10mm. are used, and the packings having grain sizes sufficiently larger than the grain sizes of the solid particles are used. Further, a packing layer 1 is provided thereon. If the grain sizes of the solid particles are limited as mentioned above, the diffusibility of air, and the effective surface area of micro films, treating efficiency and filtration efficiency are improved.</p> |
