JPH02164494A - Sewage aeration treatment tank - Google Patents

Abstract

PURPOSE:To prevent the clogging of a ceramic filter by constituting the air diffusion pipe arranged under the filter module in an aeration tank so that the caliber of each of the air supply orifices thereof is larger than 0.2mm and smaller than 10mm. CONSTITUTION:A filter module 3 formed by collecting a large number of tubular ceramic filters is provided to the upper part in the tank main body 2 of an aeration treatment tank 1 and an air diffusion pipe 4 is provided to the lower part in said tank main body 2. The caliber of the air supply orifices of the air diffusion pipe 4 is formed so as to be larger than 0.2mm and smaller than 10mm. By this constitution, the diameter of each of air bubbles injected from the air supply orifices becomes large to forcibly clean the surface of the ceramic filters and the clogging of said filters is prevented.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a wastewater aeration treatment tank.

BACKGROUND ART Conventionally, as shown in FIG. 1, a filtration module 3 in which a large number of tubular ceramic filters are assembled is arranged in a tank main body 2 of a wastewater aeration treatment tank 1, and a filtration module 3 arranged below the filtration module 3. It consisted of a diffuser pipe 4, a pump 5 for sucking filtered water from the ceramic filter, and a blower 6 for supplying air to the diffuser pipe 4. and,
The air sent into the air diffuser 4 by the blower 6 is blown out into the wastewater from the air supply port to perform aeration treatment, and also removes foreign matter adhering to the surface of the ceramic filter of the filtration module 3 to prevent clogging of the ceramic filter. Efforts were being made to prevent this.

Problems to be Solved by the Invention According to the above conventional configuration, the diameter of the air supply port of the air diffuser 4 is 2.
The diameter of the ceramic filter is approximately 0.00 μm, and there is a problem that the air discharged from the air supply port of this size increases clogging of the ceramic filter surface as the usage time increases. For example, Table 2 shows the time rate of the flow rate taken out from the filtration module when the diameter of the air supply port is 200 μm. However, the case of wastewater with MLSS of 18,000 ppm is shown.

Table 2 As shown, when the diameter is 200 μm, the extraction flow rate is decreasing.

Therefore, an object of the present invention is to provide an aeration treatment tank that can solve the above problems.

Means for Solving the Problems In order to solve the above problems, the aeration treatment tank of the present invention includes a tank body, a filtration module in which a large number of tubular ceramic filters are arranged in the tank body, and An aeration treatment tank having an aeration pipe arranged below the module, wherein the aperture of the air supply port of the aeration pipe is 200 μm.
It is configured to be larger than m and smaller than 10 mm.

Effect According to the above configuration, the diameter of the air supply port is set to be larger than 200 μm and smaller than 10 mm, so the diameter of the air bubbles ejected from the air supply port becomes large, and the surface of the ceramic filter is vigorously cleaned and clogged. is prevented.

Example An embodiment of the present invention will be described below.

That is, the diameter of the air supply port of the aeration pipe disposed below the filtration module made of a ceramic filter provided in the tank body of the aeration treatment tank is larger than 200 μm and smaller than 10 nn. Table 1 shows the temporal proportion of the flow rate taken out from the filtration module for each air supply port diameter. However, the case of wastewater with MLSS of 18,000 ppm is shown.

Table 1 It is clearly seen from Table 1 that the flow rate taken out from the filtration module did not decrease much. In other words, if the air supply port diameter is 5
When m, the bubble size is optimal, and the surface of the ceramic filter is vigorously cleaned and clogging is prevented.

The disadvantages of small and large bubble diameters are described below. When the bubble diameter is small, the rising speed of the bubbles is also small, and therefore the turbulence effect is also small, so it is presumed that the effect of cleaning the surface of the ceramic filter is small. Furthermore, if the bubble diameter is too large, the dispersion density of the bubbles becomes coarse, so that although the turbulent flow effect of each bubble is large, the effect of cleaning the surface of the ceramic filter as a whole is estimated to be small.

Effects of the Invention According to the configuration of the present invention described above, the diameter of the air supply pipe is 200 μm.
When the diameter is larger and smaller than 10 mm, clogging of the ceramic filter can be prevented and a decrease in the flow rate taken out from the filtration module can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the general structure of a conventional aeration tank. 1... Aeration treatment tank, 2... Tank body, 3... Filtration module, 4... Aeration pipe. Agent Yoshihiro Morimoto

Claims (1)

[Claims] 1. An aeration treatment tank having a tank main body, a filtration module in which a large number of tubular ceramic filters are arranged in the tank main body, and an aeration pipe arranged below the filtration module, the above-mentioned A sewage aeration treatment tank characterized in that the diameter of the air supply port of the aeration pipe is larger than 200 μm and smaller than 10 mm.