JPH027603Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is applied to sludge or suspension (hereinafter referred to as "suspension") generated in water treatment, sewage, industrial wastewater, and other water treatments.
The present invention relates to a pretreatment device for dehydrating water (collectively referred to as

[Conventional technology]

There are various systems for dehydrating suspensions generated in water treatment, industrial wastewater, and other water treatments. Belt press type dewatering machines, which dehydrate cloth belts by squeezing them using a plurality of press rolls, are attracting attention.

This belt press type dehydrator is roughly divided into a gravity dehydration section and a compression section, and the suspension is pretreated with an organic polymer flocculant in a separately installed pretreatment device, and then flocculated or granulated. After the water is removed by gravity in the gravity dewatering section, it is compressed and dehydrated using press rolls in the pressing section.

[Problems to be solved by the invention] The gravity dewatering section is provided with a sludge supply box, but when the amount of water removed in this section is large, that is, when the sludge is of low concentration, the sludge is removed from the sludge supply box. As a result, the sludge overflowed, and the amount of sludge supplied had to be reduced, resulting in a problem that the processing speed (processing amount) had to be reduced.

The present invention was developed in view of the above-mentioned conventional problems, and involves granulating and concentrating the suspended solids in the liquid from a suspension containing suspended solids to a granular solid, and then forming a separated liquid and a granulated product. The purpose is to provide a device for separating.

[Means for solving problems]

The present invention is a device for granulating and concentrating suspended solids in a suspension, in which a suspension supply pipe and a flocculant injection pipe are provided at the bottom of the tank, and a separation liquid outflow pipe is provided at the top of the tank. A rotor is provided in the inner lower part so as to generate a swirling flow, a guide hollow cylinder is provided above the rotor and below the liquid surface, and an annular rectifying plate is provided above the guide hollow cylinder in a substantially horizontal direction. established,
A granule outflow pipe is connected between the rotary blade and the annular current plate, a separated liquid outflow pipe is connected above the current plate, and a granule outflow pipe is connected above the current plate, and a granule outflow pipe is connected above the current plate, and the sedimentation separation section formed between the current plate and the liquid surface. This granulation concentration device is configured such that a sludge interface meter capable of detecting the sludge interface is installed at a suitable location, and the amount of granulated material flowing out of the granulated material outflow pipe can be controlled by a signal from the sludge interface meter. .

〔Example〕

To explain one embodiment of the present invention with reference to the drawings, a suspension supply pipe 1 and a flocculant injection pipe 2 are provided at the lower part of a tank 6 having a cylindrical or similar shape or other shape suitable for swirling flow. is connected, but this flocculant injection pipe can also open into the suspension supply pipe 1. Further, a rotary blade 3 is provided at the lower part of the tank 6 to swirl the liquid in the tank, and a guide hollow cylinder 5 is provided above the rotor blade. The shape of the rotary blade 3 may be any shape as long as it gives a swirling flow to the liquid in the tank; for example, a paddle type blade or the like is used, and the number of stages thereof is determined as appropriate. The guide hollow cylinder 5 is shaped like a cylinder similar to the tank 6 or similar to the cylinder, and is supported by a rib (not shown) on the rotating shaft ₃₁ of the rotor blade 3, suspended from above the tank, or fixedly supported on the tank inner wall. However, it is reasonable to set the outer diameter to the length of the rotor blade 3 or around it, and it can be a rotating or fixed guide cylinder.

A granule outflow pipe 10 is connected to the tank 6 at a position above the guide hollow cylinder. That is, the connection opening 10 ₁ of this granulate outlet pipe to the layer wall 6 ₁ is located above the guiding hollow cylinder 5 . Note that the connection opening 10 ₁ may be located anywhere above the rotor blade 3 and below the current plate 7 . Furthermore, an annular straightening plate 7 is arranged in a substantially horizontal direction above this granulate outflow pipe, and a separated liquid outflow pipe 9 is connected above this straightening plate, so that the flow from the straightening plate to the liquid level is connected. The content liquid forms a sedimentation separation section 13 for sedimentation and separation of the granules. Further, a conventionally known sludge interface meter 11 for detecting the sludge interface in the sedimentation separation section 13 is attached to the tank wall 6 ₁ above the rectifying plate 7 .

An electric valve 12 is provided in the middle of the granule outflow pipe 10 as a control valve for adjusting the flow rate of the granulate outflow, but it may be replaced with a solenoid valve.
The amount of granules flowing out can also be adjusted by changing the level of the outflow end of the granules outflow pipe 10 (the end opposite to the end connected to the tank wall 6 ₁ ).

The granulated material outflow pipe 10 is used as a riser pipe as shown in the figure, and the electric valve 12 is connected to the separated liquid outflow pipe 9.
It is preferable to provide it at approximately the same height as the opening (connection) to the tank 6, which has the advantage of making it easier to maintain the sludge interface at a predetermined height. In any case, the electric valve 12 is electrically connected to the sludge interface meter 11, and its opening degree is adjusted by a signal from the sludge interface meter.

As shown in the figure, the outer diameter of the baffle plate 7 is approximately equal to the inner diameter of the tank 6, and there is no gap between the outer peripheral edge of the baffle plate and the tank wall ₆₁ , so that the guide hollow cylinder Although all of the liquid in the 5-disposed portion flows into the sedimentation/separation portion 13 through the center hole (circular hole) of the current plate, there may be no problem even if there is some gap. In any case, the tank wall 6 ₁ and the guide hollow cylinder 5
Any liquid may be used as long as it can reverse as much as possible the majority of the flow of the liquid that has risen through the annular space between the guide tube and the guide hollow tube and introduce it into the guide hollow tube. Further, the guiding hollow cylinder is arranged concentrically with the tank 6 as shown in the figure, and the center hole of the rectifying plate 7 has a diameter approximately equal to the outer diameter of the guiding hollow cylinder 5, and is located directly above the guiding hollow cylinder. It is preferable to open a hole at the position, which allows the granulation action of the guiding hollow cylinder and the sedimentation separation section 13.
The separation effect can be made more effective.

The liquid depth of this sedimentation separation section 13 is 1/ of the total liquid depth of the tank 6.
It is preferable to set it as 5 or more, and by doing so, the solids concentration of the granulated material can be made higher.

In addition, in the figure, 4 is a variable speed motor, and 8 is a launder.

The suspension is supplied to the tank bottom from the suspension supply pipe 1, and the organic polymer flocculant is supplied from the flocculant injection pipe 2 to the bottom of the tank, and a swirling flow is applied by the rotary blades 3 to mix and react. The rotary blade 3 is adapted to be rotated by a variable speed motor 4. The aggregate ascends through the gap between the guiding hollow cylinder 5 and the tank wall ₆₁ while swirling.
Particles are granulated while repeatedly descending from the upper end of the guide hollow cylinder 5 inside the guide hollow cylinder.

Above the guiding hollow cylinder 5, there is a flow in two directions, a downward flow and an upward flow, and the dense granules flow downward, while the separated liquid and some of the granules flow upward and settle. The granules and the separated liquid are further separated in the separation section 13, and the separated liquid overflows into the launder 8 and is discharged from the tank 6 through the separated liquid outflow pipe 9. Therefore, the inside of tank 6 is concentrated by the amount of separated liquid that has flowed out.
The granules are discharged from the granule outlet pipe 10 and dehydrated in a separately provided dehydrator (not shown).

On the other hand, the sedimentation separation section 1
The interface of the sludge in the sludge interface meter 3 is detected, and the opening degree of the electric valve 12 is adjusted based on the signal from the sludge interface meter. This adjusts the water level in the tank 6, maintains the sludge interface at a predetermined value, and controls the amount of granules flowing out of the granules outflow pipe 10.

[Effect of idea]

The present invention can stably obtain high-quality granules with a high solids concentration through a simple configuration and simple operation, and therefore reduces the draining load in the gravity dewatering section of the belt press type dehydrator. This has the practical benefit of improving the throughput of the belt press type dehydrator.

[Brief explanation of drawings]

The drawing is a cross-sectional view of an embodiment of the present invention. 1... Suspension supply pipe, 2... Coagulant injection pipe, 3
...Rotary blade, 3 ₁ ... Rotating shaft, 4 ... Variable speed motor, 5 ... Guide hollow cylinder, 6 ... Tank, 6 ₁ ... Tank wall,
7... Current plate, 8... Ronder, 9... Separated liquid outflow pipe, 10... Granule outflow pipe, 10 ₁ ... Connection opening, 11... Sludge interface meter, 12... Electric valve, 1
3... Sedimentation separation section.

Claims (1)

[Scope of claim for utility model registration] (1) A suspension supply pipe and a flocculant injection pipe at the bottom of the tank,
In an apparatus for granulating and concentrating suspended matter in a suspension, a separated liquid outflow pipe is provided in the upper part of the tank, and a rotary blade is provided in the lower part of the tank so as to generate a swirling flow. A guide hollow cylinder is provided above and below the liquid level, and an annular baffle plate is further provided in a substantially horizontal direction above the guide hollow cylinder, and a granule outflow pipe is provided between the rotary blade and the annular baffle plate. A separated liquid outflow pipe is connected above the current plate, and a sludge interface meter is installed at an appropriate location to detect the sludge interface in the sedimentation separation section formed between the current plate and the liquid surface. A granulation concentration device configured to be able to control the amount of granulated material flowing out of the granulated material outflow pipe based on a signal from a meter. (2) The apparatus according to claim 1, wherein the liquid depth of the sedimentation separation section is 1/5 or more of the total liquid depth of the tank.