JP2604745Y2 - Activated sludge treatment equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

This invention is based on the idea that a sponge-bubble floating carrier such as polyurethane is added to an aeration tank, and microorganisms such as nitrifying bacteria and bacteria that decompose hardly decomposable substances are attached to the carrier . The present invention relates to an activated sludge treatment apparatus that nitrates organic nitrogen and ammonia nitrogen in wastewater supplied to a tank and decomposes hardly decomposable substances in wastewater.

[0002]

2. Description of the Related Art The above-mentioned activated sludge treatment apparatus is known in the prior art. In a conventional activated sludge treatment method, a nitrifying bacterium having a short growth time due to a short residence time of sludge and a degrading bacterium of a hardly decomposable substance are used. Even if it cannot be maintained within
Since the carrier provides a site capable of attaching and growing to these bacteria, as a result, the action of these bacteria can be effectively used, and wastewater can be treated with high efficiency. In particular, when the buoyant carrier is in the form of a sponge, the specific gravity is relatively close to that of water, so that the buoyant carrier is easier to flow than a precipitating carrier such as sand, activated carbon, and zeolite, so that a great effect can be obtained.

[0003]

The present invention is, however buoyant in charge
When the amount of microorganisms attached to the body increases significantly or when inorganic substances accumulate inside the sponge, the specific gravity increases and the fluidity deteriorates, and the adjacent space between the air supply air diffusers with a low flow velocity at the bottom of the tank, It may be deposited on the corners and may not function effectively. One way to prevent deposition is to lay a diffuser tube at the bottom of the tank at a high density and aerate the entire surface.However, in general, in an aeration tank for industrial wastewater treatment, a diffuser tube is used to minimize the cost. I can't answer the need to increase the number.

[0004]

Means for Solving the Problems The present invention has been developed in view of the above, and a floating carrier is added to an aeration tank to attach microorganisms, and wastewater supplied to the tank is treated by the microorganisms. in activated sludge treatment apparatus, the bottom of the aeration tank one
When installing a main diffuser to supply air into the tank in half,
In, characterized by intermittently be laid auxiliary air diffuser for aeration in order to reflow the carrier deposited on the other half of the bottom.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the illustrated embodiment, reference numeral 10 denotes an aeration tank to which a floating carrier is added, and a bottom portion for supplying air to microorganisms adhering to the floating carrier.
The main diffuser tubes 11 are laid at equal intervals. When air diffusion from the main aeration tube 11, the intracisternal water occurs convection 12 downward toward the other halves After upward from on one half of the bottom, floating carrier vessel in riding the convection The microorganisms adhering to the carrier enhance the activity by air, and nitrify organic nitrogen and ammonia nitrogen in the wastewater supplied from the raw water supply pipe 13 into the tank, or nitrify the nitrogen in the wastewater. Decomposes persistent substances. The wastewater supplied into the tank becomes treated water by staying for 2 hours or more, and overflows from the treated water pipe 14 to the outside of the tank. A screen 15 such as a wedge wire is provided at the inlet of the treated water pipe 14 to prevent the floating carrier from flowing out together with the treated water.

[0006] In this way, the carrier on which a large amount of microorganisms have adhered during operation or the inorganic substance has accumulated inside the sponge increases in specific gravity, and the other half of the bottom where the flow velocity is small in the tank, the corner of the other half, the main part, etc. It is deposited as shown by the broken line in FIG. For this reason, the auxiliary diffuser 16 is laid on the other half of the bottom or along the corner of the other half and adjacent to the main diffuser 11 to intermittently diffuse air. Aeration from the auxiliary air diffuser is performed for several tens of seconds to several minutes at intervals of about several tens of minutes to one hour.
The pressure loss of the auxiliary air diffuser 16 is set smaller than the pressure loss of the main air diffuser 11, the air from the blower is automatically reduced in the amount of air supplied to the main air diffuser, and branched to the auxiliary air diffuser. The air may be diffused simultaneously from both air diffusers 11 and 16 by one blower. In addition, air can be diffused from the auxiliary diffuser using a spare blower different from the blower for the main diffuser. In this way, by intermittently diffusing air from the auxiliary air diffuser 16 provided in a place where the buoyant carrier having increased specific gravity is easily deposited, the carrier deposited therearound flows again under an aerobic environment.

[0007]

[Effects of the Invention] As is clear from the above, in the present invention, the bottom
Convection and circulation by air diffused from the main diffuser laid in one half
Auxiliary dispersion was laid carrier deposited out of the carrier to the other half of the bottom
Since the fluid is reflowed by intermittent aeration from the gas device and participates in the treatment of the wastewater, the wastewater can be treated by maximizing the microorganisms attached and grown on the carrier . Since the air diffuser from the auxiliary air diffuser is intermittent and not continuous, it can meet the need to keep the cost as small as possible. In addition, the existing aeration tank can be easily modified and implemented.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of the device according to the present invention.

FIG. 2 is a sectional view taken along line AB in FIG.

[Explanation of symbols]

 Reference Signs List 10 Aeration tank 11 Main air diffuser 13 Raw water supply pipe 14 Treatment water pipe 16 Auxiliary air diffuser

Claims (1)

(57) [Scope of request for utility model registration] 1. An activated sludge treatment apparatus for adding a floating carrier to an aeration tank to attach microorganisms thereto and treating wastewater supplied to the tank with the microorganisms, wherein a half of the bottom of the aeration tank is provided. co When laying main air diffuser for supplying air to the vessel within the part
, The activated sludge treatment apparatus according to claim intermittently be laid auxiliary air diffuser for aeration in order to reflow the carrier deposited on the other half of the bottom.