JPH047278B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an apparatus for stirring sludge or the like in a digestion tank using a lift effect caused by blowing out fluid by blowing out gas or the like.

[Technical background of the invention and its problems] In a sludge digestion tank, a gas blowing pipe is provided in the center of the draft cylinder for stirring, and air supplied through the gas blowing pipe is directed upward from a blowing nozzle. The sludge in the digestion tank is stirred by suctioning the sludge upward and transporting it upward by the air lift effect.

A representative example of a conventional stirring device will be explained with reference to FIGS. 7 and 8. 50 is a draft cylinder;
Its upper and lower ends are open, and it is vertically installed in the sludge liquid 2 (see FIG. 1) in the digestion tank 1. Cylindrical body 50
A gas blowing pipe 51 is arranged vertically in the inner central part,
It is supported by a support body (not shown). For example, a branch pipe 52 is provided in the lower part of the blow pipe 51 in the radial direction.
is provided, and the upper end opening provided at the tip thereof communicates with a vertical blow-out nozzle 54 which is substantially a bottomed cylindrical body with only a small drain hole 53 opened at the lower part.

In the stirring device configured in this way, air supplied through the blowing pipe 51 is passed through the branch pipe 52.
The air is guided to each blow-off nozzle 54 through the air, and is blown directly upward from its upper end opening. Due to the air lift effect of the blown air, the sludge liquid 2 in the digestion tank 1 is drawn into the draft cylinder 50, rises inside the draft cylinder 50, and is discharged from the upper end. As a result, a flow of the sludge liquid 2 almost similar to that shown in FIG. 1 (however, this figure shows an example of the present invention) is generated in the sludge liquid 2, and a stirring operation is performed.

However, in this type of stirring device, the digested sludge liquid is highly concentrated and contains a large amount of fiber, and furthermore, the
2 protrudes in the radial direction (radial direction), and the blowing nozzle 54 has a large cross-sectional area and opens upward, so that the fibers of the digested sludge flow into the branch pipe 52.
The fundamental problem remains that the particles get entangled with the blow-off nozzle 54, clogging the inside of the draft cylinder 50 and reducing the stirring effect.

[Object of the invention] The object of the present invention is to solve the above-mentioned conventional problems,
An object of the present invention is to provide a gas agitation device for a digestion tank that can reliably prevent blockage in a draft cylinder and perform stable agitation for a long period of time.

[Summary of the Invention] The first invention to achieve this object comprises a vertical drafting cylinder with openings at both ends and a blowing nozzle for blowing out liquid inside the drafting cylinder. The blow-off nozzle is characterized in that the blow-off nozzle is disposed so that the blow-off fluid flow therefrom is directed obliquely upward toward the inner wall of the cylindrical body.

Further, a second invention is provided with a draft cylinder having openings at both ends and a blowout nozzle disposed inside the drafting cylinder for blowing out fluid, wherein the blowout fluid flow from the blowout nozzle swirls upward. It is characterized in that it is disposed toward the inner wall of the cylindrical body in a direction that creates a flow.

That is, the main point of the present invention is that instead of the conventional stirring device in which the blowing nozzle is arranged directly upward, the blowing nozzle is arranged diagonally upward from the center toward the inner wall of the draft cylinder.

According to this structure, as will become clear in the specific examples described later, as the sludge liquid flows upward, its fibers rise diagonally upward along the lower surface of the diagonally upward blowing nozzle. There is almost no adhesion to the nozzle, and even when looking at a certain cross section, the area occupied by the blowout nozzle is small, so the upward flow is not obstructed even in this area, and the air lift effect is the same as or better than the conventional example. becomes.

In the second invention, in addition to the idea of the first invention, the air is blown out not as a mere upward flow but as a swirling upward flow. This further promotes the stirring effect and prevents the fibers from becoming entangled.

Note that the present invention includes not only air blowing but also blowing out other fluids, such as water or sludge liquid.

[Specific Examples of the Invention] The present invention will be further explained in detail below using specific examples based on the air lift effect shown in FIGS. 1 to 6.

<First Specific Example> Figures 1 to 4 show the first specific example.
3 is a draft cylinder, inside which is a gas blowing pipe 4.
is located. The gas blowing pipe 4 is supported at the bottom of the tank 1 by an upper lid 5 or further via a support pipe 6 (FIG. 2).

In the middle of the gas blowing pipe 4, one or preferably a plurality of gas blowing nozzles 7, 7, . . . are provided at one location or at multiple locations spaced apart in the height direction.
The nozzle 7 communicates with the inside of the gas blowing pipe 4, and the leaf outlet has an elliptical shape when viewed in a horizontally cut plane. Further, the nozzle 7 protrudes radially from the gas blowing pipe 4 and is disposed obliquely upward toward the inner wall of the draft cylinder 3. In addition, the blowing pipe 4
The support pipe 6 is formed by connecting short pipes via flanges, and the blow pipe 4 and the support pipe 6 are separated by a partition plate 8.

In such a stirring device, when air A, for example, is forced into the gas blowing pipe 4, the air A flows through the gas blowing pipe 4.
The gas then changes its direction and reaches the gas blowing nozzle 7, where it is blown obliquely upward in the radial direction toward the inner wall surface of the draft cylinder 3, and then in the vertical direction. the result,
Due to the air lift effect, sludge liquid is attracted from the lower end opening of the draft cylinder 3.
It rises inside and is discharged from the upper end opening. Therefore, a flow as shown in FIG. 1 is formed in the sludge liquid 2 in the digestion tank 1, and a stirring operation is performed.

According to the present invention, the blow-off nozzle 7 is provided facing obliquely upward in the radial direction. Therefore, as shown by the arrow in FIG. 2, the sludge liquid that has risen so as to hit the inclined lower surface of the blowing nozzle 7 rises along the inclined lower surface of the blowing nozzle 7, so that the fibers of the sludge are removed with the flow. It can be lifted as it is without sticking. Therefore, clogging of the inside of the draft cylinder 3 due to adhesion of fibers to the blow-off nozzle 7 is prevented.

On the other hand, as shown in the illustrated example, it is preferable that the blow-off nozzle 7 has a uniform tubular shape over its entire length, since this can further prevent the adhesion of fibers. Now, looking back at the conventional examples shown in FIGS. 7 and 8, the fibers that rise and hit the branch pipe 52 rise along a part of the circumference, but in the longitudinal direction of the branch pipe 52. There is no flow along this point, and adhesion tends to occur at this point, and the fibers that hit the lower surface of the blow-off nozzle 54 tend to stay there. On the other hand, in the example of the present invention, the upward flow is smooth and there is no adhesion of fibers.

<Second Specific Example> FIG. 5 shows an example in which the lower end 4a of the blowing pipe 4 is conical and the support pipe 6 as in the first specific example is not used.
This is an example where it is flush with the bottom surface of a. According to this example, the adhesion of fibers that tends to occur at the attachment portion of the blow-off nozzle 7 to the blow-in pipe 4 in the example of FIG. 2 or on the bottom surface of the blow-in pipe 51 in the conventional example is reliably prevented.

<Third Specific Example> In FIG. 6, the blowing nozzle 7A is aligned along the tangential direction of the drafting cylinder 3 and diagonally upward in the radial direction in order to generate an upward swirling flow within the drafting cylinder 3. This is an example aimed at Although it is not clear from Figure 6 that it is facing upward,
It is oriented upward as in Figure 3.

According to this example, not only an upward flow but also a swirling flow is provided, so the upward stirring force within the draft cylinder 3 is large, and the adhesion and blockage by fibers can be said to be completely eliminated. This will be prevented.

[Effects of the Invention] As described above, in the present invention, since the blown fluid flow is directed diagonally upward in the radial direction, adhesion and clogging due to sludge fibers, etc. can be reliably prevented.

Further, according to the second invention, since a swirling upward flow is generated, a swirling effect is also added, and the effect of preventing adhesion and clogging becomes even more pronounced.

Furthermore, as a result of the upward flow becoming smooth with minimal pressure loss at the blow-off section, there is also the advantage that the stirring effect of the liquid in the digestion tank is improved.

[Brief explanation of drawings]

FIG. 1 is an overall schematic diagram of the device of the present invention, and FIG. 2 is a longitudinal sectional view showing details of the stirring device according to the first specific example.
Fig. 3 is an enlarged vertical cross-sectional view of the main part, Fig. 4 is a horizontal half-sectional view, Fig. 5 is a vertical cross-sectional view of the second specific example, and Fig. 6 is a horizontal cross-sectional view of the third specific example (second invention). 7 are longitudinal sectional views of the conventional example, and FIG. 8 is its horizontal sectional views. 1... Digestion tank, 3... Draft cylinder, 4...
Gas blowing pipe, 7,7A...Gas blowing nozzle, A...
…air.

Claims (1)

[Scope of Claims] 1. A device comprising a vertical draft cylinder with openings at both ends and a blow-out nozzle disposed inside the draft cylinder for blowing out fluid, wherein the blow-out nozzle is connected to the blow-out fluid flow from the cylinder. A stirring device for a digestion tank, characterized in that it is arranged diagonally upward toward the inner wall of the body. 2. A draft cylinder with openings at both ends and a straight-facing draft cylinder, and a blow-out nozzle disposed inside the draft cylinder for blowing out liquid, the blow-out nozzle being oriented so that the blowing fluid flow from it becomes a swirling upward flow. A stirring device for a digestion tank, characterized in that the stirring device is disposed toward the inner wall of the cylindrical body.