JPH0135272Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to an apparatus for biologically oxidizing organic wastewater such as sewage, human waste, and industrial wastewater, or ammonia-containing water such as water sources. It is something.

[Conventional technology]

Methods for biologically oxidizing organic wastewater and ammonia-containing water can be broadly classified into two types. The first
The second method is a suspended sludge method typified by the activated sludge method, and the second is a biofilm treatment method typified by the sprinkled bed method. The difference between these is that the former uses a group of microorganisms in suspension to exert its purification effect, whereas the latter uses a bioadhesive carrier and utilizes the biofilm that adheres to the surface of the carrier.

In recent years, biofilm treatment is a technology that has been in the spotlight as various methods have been developed along with the development of bioadhesive carriers. Among these, methods that use a carrier in a fluid state are attracting attention as a method that fundamentally solves the clogging of the carrier, which is the biggest drawback of biofilm treatment methods.

[Problem that the invention attempts to solve]

However, various measures are required to properly maintain the bioadhesive carrier in a fluid state.
In particular, if sufficient fluidity cannot be achieved due to carriers accumulating in a part of the reaction tank or remaining floating, all the carriers will not be utilized, resulting in a decrease in processing capacity and There is also the risk of secondary pollution problems, such as areas that are not used becoming anaerobic and emitting bad odors.

The purpose of the present invention is to solve these problems and provide a biological treatment device that is devised so that an ideal carrier fluidity state can be obtained in the reaction tank.

[Means for solving problems]

In the present invention, the inside of the reaction tank containing the biofouling carrier in a fluidized manner is partitioned by vertical partition walls to form a circulation chamber in the center, and an aeration chamber is formed on the outside of the circulation chamber. The circulation chamber and the air diffusion chamber are connected to each other at the upper and lower portions of the vertical partition wall, and the bottom of the circulation chamber is formed to have a high slope in the center and a low slope toward the air diffusion chamber. The present invention provides a biological treatment device characterized by:

〔Example〕

Embodiments of the present invention will be described with reference to the drawings. In the examples shown in FIGS. A carrier 4 for biofouling is fluidly accommodated therein.

The carrier 4 for biological attachment is preferably one that can be easily fluidized and can hold a large amount of microorganisms, and furthermore, one that has an appropriate size and is difficult to flow out of the reaction tank 1. Specifically, it is preferably a three-dimensional network structure with a specific gravity slightly higher than water (specific gravity 1.0 to 1.2) and a size of 10 to 50 mm square.

Furthermore, if the mesh opening is too small, substrate movement and oxygen movement into the inside of the carrier will be restricted, and the inside of the carrier will not be used effectively. Therefore, the relationship between the mesh opening and the size of the carrier is important; for example, 10
As a result of repeated experiments, it was found that the opening of the mesh to satisfy the size of ~50 mm square is preferably 1 mm or more, but that microorganisms are difficult to breed inside the carrier if it is 3 mm or more.

Next, the inside of the reaction tank 1 is divided by vertical partition walls 5, 5', and a circulation chamber A is formed in the center, and aeration chambers B and B' are formed on both sides of the circulation chamber A. An air diffuser 6 is provided at the bottom of the chamber, and the circulation chamber A and the air diffuser chambers B and B' are communicated with each other at the upper and lower portions of the vertical partition walls 5 and 5'.

What is important here is that the circulation chamber A is located in the center, and the diffuser chambers B and B' are formed symmetrically on both sides of the circulation chamber A. That is, when air is diffused from the center of the reaction tank 1, the carrier 4 may remain floating at the edge of the tank, which is particularly noticeable when using a carrier that has a low specific gravity and retains microorganisms inside. Not only do they appear and float to the surface in the form of a scum, but in severe cases, they form in large clumps that may not settle even if you poke them a little. In this way, the carrier is not used effectively and gives off a strong odor, causing problems.
If both outer sides are made into air diffusion chambers B and B', the above problem will be eliminated. In addition, since the bottom of the circulation chamber A is formed with a slope that is high at the center and low toward the diffusion chambers B and B', the flow of the carrier 4 from the circulation chamber A to the diffusion chambers B and B' is further improved. This can effectively prevent the carrier 4 from accumulating on the bottom. Although the bottom of the reaction tank 1 itself can be formed into such a shape, a slope forming plate 7 as shown in the illustrated example may also be provided.

In addition, when the scale of the reaction tank 1 increases, if a vertical plate 8 is placed on the top of the slope at the bottom of the circulation chamber A as shown in FIG. 3, the flow of the carrier 4 will be further promoted and effective. It is.

Note that 9 indicates a blower or other air source for sending air to the air diffuser 6, and 10 indicates a screen provided at the treated water outlet portion 3.

Thus, the raw water flows into the reaction tank 1 from the raw water inlet 2, and the raw water is fluidized together with the carrier 4 holding microorganisms by the air supplied from the aeration device 6 at the bottom of the aeration chambers B and B'. The water is biologically purified under aerobic conditions while circulating through the circulation chamber A, and the carrier 4 is separated by the screen 10 and flows out of the system from the treated water outlet 3. And circulation room A
is located in the center of the reaction tank 1, and there are aeration chambers B and B' on both sides of it, so circulation flow is carried out smoothly and reliably throughout the tank, and the entire reaction tank is uniformly aerobic. maintained in condition.

In the above embodiment, the case where the reaction tank 1 is square is described, but when the reaction tank 1 is circular,
As shown in FIG. 4, the circulation chamber A is
is formed in the center concentrically with the reaction tank 1, and its outer periphery is defined as an aeration chamber B. In this case, it is preferable that the slope at the bottom of the circulation chamber A has a conical or pyramidal shape. Moreover, the effect is the same as in the above-mentioned square tank.

[Effect of idea]

As described above, the present invention has the following extremely useful effects.

Biofouling carriers do not accumulate in a part of the reaction tank.

The carrier for bioadhesion does not float up in a part of the reaction tank and form a scum.

The entire interior of the reaction tank can be maintained in an aerobic state and no bad odor is generated.

Proper fluidization of all biofouling carriers ensures maximum throughput at all times.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view, Fig. 2 is a plan view thereof, Fig. 3 is a sectional view showing an example near the center bottom of Fig. 1, and Fig. 4 is a cross-sectional view showing another example. It is a top view showing an example of. A... Circulation room, B, B'... Diffusion room, 1... Reaction tank, 2... Raw water inlet, 3... Treated water outlet,
4...Carrier, 5,5'...Vertical partition wall, 6...Diffuser, 7...Slope forming plate, 8...Vertical plate, 9...
Air source, 10...screen.

Claims (1)

[Claims for Utility Model Registration] (1) The interior of a reaction tank in which a bioadhesive carrier is fluidly accommodated is partitioned by vertical partitions to form a circulation chamber in the center and an aeration chamber outside the chamber. death,
An air diffuser is provided at the bottom of the air diffusion chamber, the circulation chamber and the air diffusion chamber are connected to each other at the upper and lower portions of the vertical partition, and the bottom of the circulation chamber is higher at the center and lower toward the air diffusion chamber. A biological treatment device characterized by being formed on a slope. (2) The biological treatment device according to claim 1 or 2, wherein the bioadhesive carrier is a three-dimensional network structure with a specific gravity of 1.0 to 1.2 and a size of 10 to 50 mm square.