JPS58297A - Flowing bed type contact oxidation device - Google Patents

Abstract

PURPOSE:To perform stable oxidation treatment by packing fluid media of <=1 specific gravity which flow downward in a flowing tank. CONSTITUTION:When air is fed into an air dissolving pipe 2, waste water is inevitably sucked from the bottom end of the pipe 2 by an air lift effect and while it ascends, the air is dissolved into the waste water. At the same time, the waste water is given the velocity of downward flow in a flowing bed part 5. In the bed 5, fluid media 4 of <=1 specific gravity stuck with aerobic microbes are kept floated in the upper part of the flowing bed, are given the velocity of downward flow; at the same time, they are flowed downward in the flowing bed part and the lower interface of the fluid media is formed upper than the bottom end of the pipe 2. In this method, the always stable oxidation treatment is accomplished without clogging by the aerobic microbes.

Description

DETAILED DESCRIPTION OF THE INVENTION The conventional activated sludge method is difficult to manage sludge in an aeration tank and in post-treatment, and is therefore unsuitable for small-scale treatment of organic wastewater. A method of attaching living organisms to a medium and oxidizing it has begun to be adopted.

Among these, a fluidized bed method was considered as a method that could increase contact efficiency and contact area.

The present invention relates to a fluidized bed catalytic oxidation apparatus that uses a fluidized medium with a specific gravity of less than 1, as opposed to conventional media that use materials with a specific gravity of more than 1.

Conventional fluidized bed oxidation treatment equipment uses sand or activated carbon with a specific gravity greater than 1 as the fluidizing medium, and provides upward flow velocity for fluidization, which requires air aeration to supply the oxygen necessary for aerobic microorganisms. If it is carried out in a fluidized bed, the fluidized bed will be disturbed, causing problems such as outflow of the fluidized medium, making operation management very difficult.

A dissolution tank was required to dissolve air in the treated water in advance, making the equipment complicated.

As a device that solves this problem, an air lift or the like is installed in the fluidized tank, and the air lift lifts the medium with a specific gravity of more than 1 to the top of the tank, and at the same time performs air dissolution, causing the medium to fall from the top of the tank. Therefore, there is a method of contact treatment. However, since a medium with a specific gravity greater than 1 is used, the medium with aerobic microorganisms attached to the bottom of the tank tends to settle and stick, causing the problem that the medium cannot be transferred to the top of the tank by air lift. Since the microorganisms constantly pass through the airlift, even if aerobic microorganisms adhere to the surface of the medium, they are constantly peeled off. The disadvantage was that it was not possible.

Therefore, the present inventor has devised an apparatus for forming a stable fluidized bed of fluidized medium while dissolving oxygen necessary for aerobic microorganisms in a liquid to be treated within the fluidized bed.

The structure and operation of the present invention will be explained below with reference to the drawings.

FIG. 1 is a cross-sectional diagram of one embodiment of the present invention.

In Fig. 1, the fluidized bed (1) includes an air dissolving section (3) formed by an air dissolving tube (2) inside the tank, and a fluidized bed section (4) that forms a fluidized bed filled with a fluidized medium (4) around the air dissolving section (3). 5).

In this embodiment, there is only one gas dissolving pipe (2), but depending on the amount of water to be treated, multiple pipes may be installed.

A compressor (7) is installed at the lower end of the air dissolving tube (2).
A blowing pipe (6) for air to be press-fitted is installed.

At the same time, to-be-treated water (wastewater containing organic matter) is sent from the to-be-treated liquid pump (8) to the air blowing pipe (6), which serves as a to-be-treated water supply port.゛Air dissolving tube (
When air is sent to 2), wastewater is inevitably sucked in from the lower end of the air dissolution tube (2) due to the air lift effect, and air is dissolved into the wastewater while rising up the air dissolution tube (2).

At the same time, a downward flow velocity is given in the fluidized bed section (5).
.

In the fluidized bed section (5), a fluidized body (4) having a specific gravity smaller than 1 and containing aerobic microorganisms floats above the fluidized bed.
At the same time when a downward flow velocity is applied, the fluidized bed section is caused to flow downward, and a lower interface of the fluidized medium is formed above the lower end of the air dissolving tube (2).

When a fluid medium with a specific gravity of more than 1 is used as in the past, there is a drawback that the fluid medium is deposited together with aerobic microorganisms at the bottom of the tank, where the flow condition is not good, and the fluid medium sticks.

In the present invention, along with the oxidation treatment, a film of aerobic microorganisms is formed on the surface of the fluidized medium, increasing the porosity within the fluidized bed, preventing sedimentation and coalescence of the fluidized media, and automatically removing the fluidized media with excessive microorganisms attached. The air dissolving tube pops out of the fluidized bed (
2), the attached microbial film is peeled off and sent to the upper part of the fluidized bed again, so that there is no blockage by aerobic microorganisms, and stable oxidation treatment is always performed.

Furthermore, in the present invention, a radius of 500 mm is provided at the top of the air dissolving tube (2).
It has a cap-like shape curved at an angle of ~600 am, and a liquid distribution plate (9) with a large number of protrusions on the inside thereof is provided. By allowing the liquid to be treated to fall evenly onto the upper surface of the fluidized bed depending on the ratio, the fluidized medium at the upper interface of the fluidized bed can be constantly pulsated to prevent the fluidized medium from sticking and to increase the air dissolution efficiency.

The liquid distribution plate (9) may be suspended from the canopy or fixed to the wall by supports.

There is an air discharge pipe Q1 at the top of the fluidized bed (1), and the pressure inside the fluidized bed is kept constant by means of a regulating valve α. Also fluidized bed (1)
There is a treated water discharge pipe (2) at the bottom of the fluidized bed, so that the treated water can be discharged in a timely manner through a valve Q4 that is linked to a liquid level controller (2) installed above the fluidized bed. A is a pressure gauge and a is a safety valve.

In this example, the upper part of the fluidized bed is sealed.

It can also be done with the top open. FIG. 2 is a cross-sectional diagram of another embodiment of the invention.

This is partially different in structure from the method shown in Figure 1.

Its main structure is the same as in Figure 1. Only air dissolving part (
3) is provided outside the fluidized tank (1), and the liquid to be treated is circulated by a pump cI't). Moreover, the entire middle part of the fluidized tank (1) is occupied by a fluidized medium (4) having a specific gravity of less than 1.

The liquid to be treated is sent by a pump (8) and sent to a compressor (
7), air is injected into the air dissolving tube (2) through the inlet.
) will be sent to. Next, the liquid to be treated (wastewater containing organic matter) into which air is pressurized by the circulation pump C17) ascends the air dissolution pipe (2) and is guided to the upper space of the fluidization tank (1).
The liquid to be treated is evenly spread over the surface of the fluid medium (4) through the liquid distribution pipe (9)', and the liquid to be treated flows downward through the fluid medium (4) and adheres to the surface of the floating fluid medium (4). It is biooxidized by microorganisms, descends, and returns to the fluidized tank (
The liquid is sucked in from the liquid inlet o6 at the bottom of 1) by the circulation pump of) and circulated through the air dissolving pipe (2).

The treated saliva is fed to pulp a which is linked to the liquid level controller (2).
Other auxiliary equipment for appropriately discharging liquid from the liquid discharge pipe (2) having 4 is the same as that shown in FIG. This method uses a fluidized bed section (5)
However, since the air dissolving section (3) is provided outside, there is a drawback that the area required for public officials is increased.

As mentioned above, the biggest problems in the catalytic oxidation method, such as blockage of the fluid medium (4) and the phenomenon of coalescence of media, can be solved by using a medium with a specific gravity of less than 1 as the fluid medium. We were able to perform stable oxidation treatment.

As the fluid medium described in the examples, for example, polyethylene particles (diameter between 6 and 4) with a specific gravity of 0.96 are used at 65 to 40 vol.
% slurry. Other plastics and particles may also be used.

In the method shown in Figure 1, the BOD of the liquid to be treated is 300~4'OOp
pm organic wastewater with a BOD load of 5 Kg-BOD/rn
”D, after oxidation treatment at fluidized tank internal pressure I Kri, BOD of 20 ppm after SS removal was obtained.
Organic wastewater with a high concentration of 600ppm has a BOD load of 3
After the oxidation treatment with Kp-B OD/rn"l), the treated water had a BOD of 200 ppm or less after SS removal.

As shown in the above two results, stable oxidation treatment was carried out with no aerobic microorganisms sticking to the fluidized medium in both BOD, low concentration, and high concentration.

[Brief explanation of drawings]

Fig. 1 is a sectional diagram of one embodiment of the present invention, and Fig. 2 is a sectional diagram of another embodiment of the invention. pipe, (3) is the air dissolving part. (4) is a fluidized medium, (5) is a fluidized bed section, and (6) is an air blowing pipe. (7) is a compressor, and (8) is a pump for treated water. (9) is a liquid distribution plate, (9) is a liquid distribution pipe, (10 is an air discharge pipe), (Q) is a control valve, (6) is a treated water discharge pipe, and (G) is a liquid level controller. α◆ is pulp, O→ is pressure gauge, DI is safety valve. αη is a circulation pump, and 01 is a treated water supply port. α Camphor is the liquid inlet patent applicant Mitsubishi Kakoki Co., Ltd. agent (7167) Kentake Hattori 1st v! J

Claims (3)

[Claims] (1) In a fluidized bed type catalytic oxidation device in which a fluidized medium to which aerobic microorganisms are attached is present in the tank, and the fluidized medium is brought into contact with organic wastewater for oxidation treatment while flowing under aerobic conditions, An air dissolving section and a fluidized bed section are provided, and a water supply port into which air is pressurized is provided at the lower end of the air dissolving section.
In addition, a liquid dispersion plate is attached to the upper part of the air dissolving section, and the fluidizing tank section is filled with a fluidizing medium that flows downward and has a specific gravity of less than 1. At the bottom of the tank, there is a processing liquid drain. Fluidized bed catalytic oxidation device with outlet (2) The fluidized bed catalytic oxidation device according to claim 1, wherein the liquid dispersion plate has a curved cap shape and has several protrusions on its inner surface. (3) In a fluidized bed type catalytic oxidation device in which a fluidized medium to which aerobic microorganisms are attached is present in a tank, and the fluidized medium is brought into contact with organic wastewater for oxidation treatment while flowing under aerobic conditions, An air dissolving section is installed outside the tank, and a fluidized bed section is installed in the middle of the tank. It is connected to a certain liquid distribution pipe, and the lower end of the air dissolving section is connected to the liquid inlet (l) provided at the lower part of the tank through the pipe and circulation pump af).
The fluidized bed section that occupies the middle part of the tank is filled with a fluidized medium that flows downward and has a specific gravity of less than 1, and the bottom of the tank has a treatment liquid outlet. oxidizer