JPH05192699A - Flocculation reaction device - Google Patents

Abstract

PURPOSE:To enable the formation of pellets having large grain sizes and high strength even if the diameter of a treating chamber is large by constituting the stirring vanes of the lowermost stage of a disk which is fixed to a revolving shaft and flat plate-shaped retrograding vanes which are fixed at the base parts perpendicularly to the peripheral edge of the disk and retrograde and curve increasingly toward the front end. CONSTITUTION:The stirring vanes 12 of the lowermost stage swiveling in the bottom in the treating chamber 1 are constituted of the disk 13 which is fixed concentrically and level to the revolving shaft 2 and plural sheets of the flat plate-shaped retrograding vanes 14 which are fixed at the base parts orthogonally and perpendicularly to the circumferential part of the disk 13 and are curved to retrograde increasingly toward the front end. Consequently, the upper swirling and circulating flow B and lower swirling and circulating flow B' generated by the flat plate-shaped retrograding vanes 14 of the lower-stage stirring vanes 12 swiveling in the bottom in the treating chamber 1 are prevented from being shut off by the disk 13 and from shorting in the central part in the bottom in the chamber 1. Then, the vigor of the flow is decreased by the shorting in the event of the shorting and a dead space is generated in the central part of the bottom in the chamber 1 but there is no shorting and, therefore, the upper and lower swirling and circulating flows B, B' grow to the large and continuous flow without losing the vigor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention receives sludge and a coagulant at the bottom of a treatment tank, and agitates sludge with a plurality of vertical stirring blades horizontally swirling in the tank to aggregate and granulate sludge, The present invention relates to an aggregating treatment device that agitates sludge by agitation with a plurality of stages of agitation blades to agglomerate and granulate, and discharges sludge from the upper part of a treatment tank to the outside of the tank.

[0002]

2. Description of the Related Art As such an aggregating apparatus, a battledore-shaped retreating blade having a base width smaller than that of a tip portion in order to cause a lower stirring blade to generate a vertical swirling circulation flow, and an upper stirring blade in a horizontal direction. Japanese Patent Publication No. 2-8 that uses flat plate radial blades with a constant width in the height direction of the tank to generate a swirling flow.
It is known from Japanese Patent No. 761. By swirling, this lower battledore-shaped swept blade strongly ejects sludge at the center of the bottom of the tank to the outside, and its flow is swirling and divided into an upflow and a downflow near the inner circumference of the treatment tank, and rises. The flow comes into contact with the horizontal swirl flow generated by the flat radial blades in the upper part of the tank, and descends while swirling toward the center of the bottom of the processing tank. Further, the descending flow rises toward the center while swirling along the bottom surface of the processing tank. In this way, at the bottom of the tank, the upper and lower swirling circulation flows are generated to the same extent due to the swirling of the battledore-shaped backward blades, and these upper and lower swirling circulation flows are vigorously mixed in the central part of the tank to improve the mixing effect of sludge and coagulant. , Flock promotes contact and association with each other, and granulates into lumps with large particle size and strength.

[0003]

The above-mentioned conventional apparatus is effective when the diameter of the treatment tank is relatively small. The fluidity of the liquid in the part deteriorates, so-called dead space (voltech score) occurs, and sludge cannot be granulated well.

[0004]

In view of the above, the present invention has been made in view of the above.
As a result of studying various types of blades, it was developed, and the lowermost stage stirring blade that swirls at the bottom of the tank is fixed concentrically and horizontally to the rotating shaft. It is characterized in that the base part is fixed perpendicularly to the peripheral part and is perpendicular to the peripheral part, and is composed of a plurality of flat plate retracting blades curved so as to recede toward the tip.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the illustrated embodiment, 1 is a cylindrical processing tank, 2 is a vertical installation in the center of the processing tank 1, and a rotating shaft is driven to rotate in one direction by a motor and a transmission. A sludge supply pipe for supplying sludge to the bottom, and a chemical injection pipe 4 for adding a coagulant such as an amphoteric polymer to sludge is connected in the middle of the sludge supply pipe. In addition, the upper end of the rotary shaft 2 is supported by a support 5 provided in a bridge shape on the upper surface of the processing tank 1, and the motor and the transmission are installed on the support 5.

In this embodiment, the rotating shaft 2 is provided with agitating blades 10 and 12 in two stages, that is, upper and lower, in a substantially radial manner. The upper-stage stirring blade 10 is a flat plate-shaped radial blade 11 having a constant width in the height direction of the tank over the entire length, and is 1 with respect to the rotating shaft 2.
Two pieces are attached at a phase of 80 °. The lower stirrer blade 12 has a disc 13 fixed concentrically horizontally with respect to the rotating shaft 2, and a base portion 14a perpendicularly fixed to the peripheral edge portion of the disc vertically so that the base portion 14a is swiveled in a turning direction from the base portion toward the tip 14b. The plate-shaped retreating blade 14 is curved so as to retreat, and the plate-shaped retreating blade 14 also has a constant width in the height direction of the tank from the wide end of the diverging base to the tip as shown in the drawing. It is fixed at a phase of 180 ° with respect to the peripheral portion. Further, on the inner circumference of the bottom portion and the inner circumference of the middle portion of the processing tank, there is provided a guide plate 15 which is gradually separated from the inner circumference of the tank in the swirling direction of the stirring blades 10 and 12.
Two sheets are provided with a phase of °.

When the rotary shaft 2 is rotated while supplying the sludge to which the coagulant has been added by the mud supply pipe 3 to the bottom of the treatment tank, the upper stirring blade 10 and the lower stirring blade 12 swivel together to form the upper stirring blade. Is a flat radial blade 11, a horizontal swirling flow A is generated in the upper part of the tank, and at the bottom of the tank, the disk 13 of the lower stirring blade is the handle part of the battledore, and the flat retreating blade 14 is the plate portion of the battledore. Since the flat plate type retreating blade is curved so as to retreat in the swirling direction as a whole, the swirling strongly pushes out the sludge in the center of the bottom of the tank to the outside. 1 divided into an upflow and a downflow near the inner circumference, and the upflow contacted the horizontal swirl flow A caused by the upper stirring blade in the upper part of the tank, and descended while swirling toward the center of the bottom of the processing tank. Becomes the upper swirling circulation flow B that circulates as Turning along the bottom surface of the physical vessel becomes lower swirling circulation B 'which rises towards the intracisternal center. The guide plate 15 on the inner circumference of the middle stage promotes the upper swirling circulation flow B to descend toward the inner center of the tank while swirling, and the guide plate 15 on the inner circumference of the bottom moves the lower swirling circulation flow B'to the center of the tank. Helps to rise towards the section.

The upper swirling circulation flow B that descends toward the center of the bottom of the tank and circulates, and the lower swirl circulation flow B'that rises toward the center of the bottom and circulates the disc 1
Since it is blocked by 3 and does not short-circuit, each of the swirling circulation flows B and B ′ circulates without being repulsed, and is strong and large.
A continuous and even swirling circulation flow is formed, and sludge that is trying to accumulate on the disc 13 or sludge that is trying to stay under the disc 13 is caught in the flow and cannot be deposited or stayed.

Thus, the sludge and the coagulant supplied from the mud supply pipe 3 to the bottom of the tank ride on the upper and lower swirling circulation flows B and B ', and are sufficiently mixed to grow into flocs, and some flocs come into contact with each other. , I met and became a sludge lump. Then, the flocs and sludge lumps moving on the upper and lower swirling circulation flows B and B ′ are gradually pushed up by the subsequent sludge supplied to the bottom of the tank and are entrained in the horizontal swirling flow A caused by the upper stirring blade 10. And
At this time, the flocs come into contact with the sludge mass and adhere,
The granules are pressed against the inner peripheral surface of the processing tank 1 and roll on the inner peripheral surface, and are granulated into large particles while increasing the density and the strength, and the granulated pellets are sequentially discharged from the outlet 6. The separated water from which the granulated pellets have been separated may be overflowed into an overflow gutter (not shown) provided at the upper end of the treatment tank and drained. A filtration tank 7 may be additionally provided to prevent sludge from entering the tank with a slit or other filter, and the sludge may be drained to the outside. When the filtration tank 7 is provided on the inner circumference of the treatment tank, the filter 8 is provided on the bottom wall of the filtration tank, and when it is provided on the outer circumference of the treatment tank, the filter 8 is provided on the inner circumference of the filtration tank.

[0010]

As is apparent from the above, according to the present invention, the upper swirling circulation flow B and the lower swirling circulation flow B'generated by the flat plate type retreating blades 14 of the lower stage stirring blade 12 swirling at the bottom of the tank.
Is blocked by the disk 13 and does not short-circuit at the center of the bottom of the tank. Therefore, if a short circuit occurs, the momentum of the flow will decrease,
Although there is a dead space in the center of the bottom of the tank, since there is no short circuit in the present invention, the upper swirl circulation flow B and the lower swirl circulation flow B ′ do not lose their momentum and become a large and continuous flow. Even if the tank has a large diameter, it is possible to granulate strong pellets having a large particle size.

[Brief description of drawings]

FIG. 1 is a sectional view of an entire agglutination reaction apparatus.

FIG. 2 is an enlarged sectional view taken along line II-II in FIG.

FIG. 3 is a perspective view showing a swirling state of an upper stirring blade and a lower stirring blade.

[Explanation of symbols]

 1 Processing Tank 2 Rotating Blade 3 Mud Supply Pipe 4 Chemical Injection Pipe 5 Support 6 Granule Pellet Outlet 7 Filtering Tank 8 Filter 10 Upper Stage Stirring Blade 11 Flat Radial Blade 12 Upper Stage Stirring Blade 13 Disc 14 Flat Plate Retracting Blade 15 Information board

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Matsunaka 3-4-7 Nishishinjuku, Shinjuku-ku, Tokyo Kurita Industry Co., Ltd.

Claims (1)

[Claims] 1. A treatment tank for receiving sludge and a coagulant in the bottom portion and allowing granulated sludge to flow out from the upper portion, and a plurality of stages vertically attached to a rotary shaft vertically provided in the central portion of the treatment tank. In an agglomeration reaction apparatus equipped with a stirring blade that swirls in water in a treatment tank, the lowermost stirring blade is a disk that is horizontally concentrically fixed to the rotating shaft, and the base part is the peripheral part of the disk. An agglutination reaction device comprising a plurality of flat plate-shaped retreating blades which are orthogonally fixed vertically and curved so as to recede toward the tip.