JPS5821600Y2 - Closed type anaerobic digestion tank for water treatment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a closed type anaerobic decomposition tank for water treatment in which organic components in water to be treated are subjected to methane fermentation using anaerobic bacteria.

In the above tank, methane gas produced by fermentation during treatment is taken out from the top of the tank, but as the scum in the water to be treated rises to the liquid level in the tank, the floating scum solidifies with each other. As the solidification progresses, a scum layer is formed covering the entire liquid surface in the tank, resulting in
The scum layer was lifted by the methane gas, making it difficult to take out the methane gas, and the pressure inside the tank increased significantly, causing the tank to burst.

In view of the above points, it is an object of the present invention to prevent damage to the tank due to consolidation of floating scum.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

A hollow cylindrical inner pipe 2 is fitted into a bottomed cylindrical outer pipe 1 buried deep underground for a distance of several tens of meters to more than a hundred meters, and a water tank 1a is connected to the upper part of the outer pipe 1. The upper opening of is closed by attaching an upper lid 3, and a screw 4 is provided above the inner pipe 2 to cause the water to be treated to flow downward, and a descending flow path R1 is formed within the inner pipe 2. With,
Between the inner tube 2 and the outer tube 1, an ascending channel R2 is formed which is connected to the descending channel R1 via natural flow channels R and R above and below, respectively, and a rising channel R2 is provided through the supply channel r. The treated water containing anaerobic bacteria is passed through the flow path R1tR,
The anaerobic decomposition tank 5 is configured to circulate through R2 and R, thereby forming a closed type anaerobic decomposition tank 5 for water treatment in order to perform methane fermentation treatment on organic components in water to be treated such as urban sewage and industrial wastewater using anaerobic bacteria. It is.

A methane gas recovery device 6 is connected in communication with the upper lid 3, and is configured to recover methane gas produced by fermentation for later use, such as fuel for a melting furnace in post-processing.

Rod-shaped members 8a and 8b, which serve as rotating members 8 for crushing floating scum, are mounted on the driving rotation shaft 1 of the screw 4 at positions corresponding to or near the liquid level in the tank, and are arranged with different phases up and down. The structure is such that the floating scum is attached in a radially extending state to suppress the solidification of the floating scum.

As shown in the above embodiments, the characteristic structure of the sealed anaerobic digestion tank for water treatment according to the present invention is a deep-type sealed water treatment tank that processes organic components in the water to be treated by methane fermentation using anaerobic bacteria. In an anaerobic decomposition tank, a rotating member 8, which is placed at or near the liquid level in the tank and acts on the floating scum to suppress its solidification, is shifted up and down in phase. Since the points are provided in a radially extending state, such a configuration provides the following effects.

In other words, by the action of the floating scum solidification suppressing device 8, it is possible to reliably avoid an inconvenient situation in which methane gas generated during anaerobic decomposition becomes a solidified scum layer and cannot be discharged from the decomposition tank, and as a result, methane gas Accidents in which the decomposition tank is destroyed due to an abnormal rise in pressure inside the tank due to stagnation can be prevented, and the required strength of the decomposition tank can be lowered, effectively reducing equipment costs for the tank. Became.

In a deep type anaerobic decomposition tank, a fairly dense floating scum layer is formed on the liquid surface, but in order to reliably crush it, a stirring device is installed at a location corresponding to the liquid surface.
Since the rotating member has different phases vertically and extends radially, the floating scum layer on the liquid surface is rippled by the rotation of the lower rotating member, and the rippled floating scum layer is rotated vertically. It is possible to reliably crush the material by hitting it alternately with the parts.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the closed type anaerobic decomposition tank for water treatment according to the present invention, in which FIG. 1 is a schematic vertical cross-sectional view of the entire structure, and FIG. 2 is a cross-sectional view taken along the line ■--■ in FIG. 4... Stirring device, T... Drive rotating shaft, 8... Floating scum solidification suppressing device, rotating member.

Claims (1)

[Scope of Claim for Utility Model Registration] ■ A deep-type closed anaerobic decomposition tank for water treatment in which organic components in water to be treated are subjected to methane fermentation by anaerobic bacteria, at or near the liquid level in the tank, A closed type anaerobic water treatment device characterized in that a rotating member 8 that acts on floating scum to suppress its solidification is provided in a state in which the rotating member 8 is vertically shifted in phase and extends radially. Decomposition tank. (2) The floating scum solidification suppressing device is a rotating member 8 attached to the drive rotation shaft 7 of the stirring device 4 for the water to be treated in the tank, as set forth in claim (2) of the utility model registration claim. Closed type anaerobic digestion tank for water treatment.