| 摘要 |
PURPOSE:To provide a compact nitrification and denitrification treatment apparatus capable of efficiently performing nitrification and denitrification treatment using a single treatment tank, reduced in washing frequency and capable of being simply washed. CONSTITUTION:In a high-degree purification device of org. sewage, an upstream fixed bed A, a downstream upper fixed bed B and a downstream lower fixed bed D are arranged through a partition wall C and a porous member is provided to the lower part of the device and an air diffusion member aerating at least the fixed bed B is provided and raw water is supplied to the fixed bed A from the raw water supply pipe 2 provided to the lower part of the fixed bed A to be upwardly passed through the fixed bed A and overflows the partition wall C at the upper part of the device to flow in the fixed bed B to be successively passed through the fixed beds B, D as a descending stream and a means refluxing a part of the outflow water from the fixed bed D to the fixed bed A and a means allowing the other part of the outflow water to flow out as treated water are provided to the lower part of the device. |
