JPS595033B2 - flotation separation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that aggregates sludge in water to be treated using air bubbles and floats it to separate it, and has been modified so that it can efficiently float and separate it while suppressing the rise in equipment costs as much as possible. The purpose is to do.

Next, embodiments of the present invention will be described with reference to illustrative figures.

The sludge-containing treated water supplied from the water treatment equipment 1 and the flocculant from the flocculant supply device 2 are mixed by a stirring device 3, and a flocculation mixing tank 4 is provided to flocculate the sludge with a chemical solution, An aeration tank 6 configured to cause the water to be treated that overflows from the coagulation mixing tank 4 to flow downward and to be aerated with air from the nozzle 5 is provided, and the water to be treated from the aeration tank 6 is raised in the mud tank portion 7a. A flotation separation tank 7 is provided which is configured to aggregate the sludge with air bubbles and float and separate it while flowing.

A pipe 8 for supplying a flocculation aid is provided deep in the aeration tank 6 to promote sludge flocculation, and a spiral upward flow path is formed near the bottom of the mud tank portion 7a. By installing a screw 9 inside the sludge and extending the ascending flow path, the probability of contact between the sludge and air bubbles is increased, and the dissolution of air bubbles flowing from the aeration tank is promoted. The structure is designed so that flotation and separation can be carried out efficiently as a whole.

The floated sludge is transferred to the upper part of the flotation separation tank 7 in a sludge trough 10.
A raking device 11 for feeding fresh water into the tank, and a treated water trough 12 for taking out fresh water are provided.

The maximum depth of the flotation separation tank 7 is generally about 10 m, but it can be changed as necessary, and the means for supplying the water to be treated to the mud tank section 7a can also be changed in various ways. There is a configuration for this purpose, which is collectively referred to as a treated water supply channel 6.

Further, it is advantageous to dispose the screw 9 near the bottom as described above, or over the entire length or almost the entire length of the mud tank portion 7a, as this can promote bubble dissolution. The screw 9 may be placed at the top or near the top;
The length, shape, pitch, etc. can be changed as necessary.

In summary, the present invention provides the flotation separation device described above.
At least part of flotation tank 7? a is relatively deep, and a water supply flow path 6 to be treated is connected to the mud tank portion 7a near the bottom thereof, and a screw 9 for forming a spiral ascending flow path is installed inside. Specifically, the gas dissolved in the water to be treated, which is supplied near the bottom of the exploration portion 7a, can be turned into bubbles as the water to be treated rises, so extremely fine bubbles can be uniformly and in large quantities. The situation existing in the treated water can be expressed, and the contact efficiency between sludge and air bubbles can be increased. Furthermore, the action of the screw 9 can fragment the air bubbles and extend the time for contact between sludge and air bubbles. This also increased the contact efficiency between the sludge and air bubbles, and significantly improved the sludge flotation separation efficiency as a whole.

As mentioned above, as a means to improve flotation separation efficiency, for example, the exploration section 7a can be made into a simple straight pipe shape and made extremely deep, or the exploration section 7a itself can be made into a zigzag shape. , the height above ground and the depth of underground burial are extremely high, requiring a large amount of equipment cost,
In addition, the latter greatly increases the cost of the exploration part Ia itself, and if the underground type is used, the diameter of the borehole becomes large and the excavation work requires a large expense, both of which greatly increase the equipment cost. There are disadvantages associated with this.

On the other hand, according to the present invention, the exploration portion 7a is made as short as possible by simply incorporating the screw 9, so that it is possible to effectively suppress the increase in equipment costs.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the flotation and separation apparatus according to the present invention, and FIG. 1 is a schematic longitudinal sectional view, and FIG. 2 is a longitudinal sectional view taken along the line 1--2 of FIG. 1. 6...Water supply channel to be treated, 7...Flotation separation tank, 7a...Exploration section, 9...Screw.

Claims (1)

[Scope of Claims] 1. A device for flotation separation by agglomerating sludge in water to be treated using air bubbles, which comprises at least a portion 7 of a flotation separation tank 7.
a is relatively deep, and a water supply flow path 6 to be treated is connected to the mud tank portion 7a near the bottom thereof, and a screw 9 for forming a spiral ascending flow path is installed inside. A flotation separation device featuring: 2. Claim 1, characterized in that the lower end of the screw 9 is disposed near the bottom of the mud tank portion 7a.
The equipment described in section.