JP3255473B2 - Filtration concentration device and filtration concentration method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for separating and recovering a filtrate and a concentrated suspension by filtering a suspension.
In particular, the present invention relates to a filtration and concentration apparatus and a filtration and concentration method in which the efficiency of filtration operation is improved by increasing the removal efficiency of filter residue deposited on a filter medium.

[0002]

2. Description of the Related Art As a device for filtering and concentrating a large amount of suspension, a vertical filter medium is provided in a lower stock solution chamber, and a filtrate chamber communicating with the inside of the cylindrical filter medium is provided in an upper portion. Filters are known. In order to filter and concentrate the undiluted solution using such a filter, the undiluted solution is supplied under pressure to the undiluted solution chamber by a pump or the like, and the filtrate is collected from the filtrate chamber. When the filtration efficiency drops due to accumulation of filter residue around the filter media, first stop the supply of the undiluted solution, then open the drain pipe connected to the lower part of the undiluted solution chamber to discharge the undiluted solution, and at the same time drain the undiluted solution as necessary. The filter medium is backwashed by supplying pressurized air or the like to the chamber to cause the filtrate in the filtrate chamber to flow backward, and the liquid containing the filter cake separated from the filter medium is sent to a separately provided waste tank through a drain pipe. To restore the filtration efficiency.

[0003] However, in such a filtration and concentration method, when the filter cake accumulates on the filter medium, the filtration operation is stopped and the filter medium is washed and regenerated. The filtration step must be frequently interrupted, and not only the time required for the backwashing step but also the time required for switching the steps becomes longer, resulting in a problem that the operating efficiency of the filter is reduced. .

On the other hand, in order to shorten the time required for the filter medium backwashing step, means for increasing the pressure of the air supplied into the filtrate chamber to increase the backflow speed of the filtrate has conventionally been adopted. When the pressure is increased, a device with high pressure resistance is required, so that there is an economical restriction, there is a limit to the time reduction, and there is also a problem that the filter medium is easily damaged.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a filtration / concentration apparatus and a filtration / concentration method capable of further increasing the operation efficiency of a filtration device. The purpose of the present invention is to achieve the above object by shortening the switching time between the backwashing step and the backwashing step and simplifying the backwashing step.

[0006]

SUMMARY OF THE INVENTION Accordingly, a filtration and concentration apparatus according to the present invention provides a stock solution storage tank for stocking a stock solution to be filtered.
And a stock solution chamber to which stock solution is supplied from the stock solution storage tank and the stock solution chamber.
A filter medium was provided from the liquid chamber and filtered by the filter medium.
A filter provided with a filtrate chamber for receiving the filtrate;
The filtrate collected from the filtrate recovery path is connected to the filtrate recovery path.
The filtrate storage tank and the undiluted solution between the undiluted solution storage tank and the undiluted solution chamber.
A stock solution pump that alternately repeats supply and suction of
Connect the liquid suction side of the stock solution pump to the stock solution storage tank, and
The undiluted solution sucked by the undiluted solution pump from the storage tank is
And a liquid discharge side of the raw liquid pump.
And the undiluted solution chamber, and introduced through the undiluted solution suction passage.
Stock solution supply path for feeding the stock solution to the stock solution supply side of the stock solution chamber
And a liquid supply side of the liquid concentrate chamber and a liquid suction of the liquid concentrate pump.
Undiluted solution in the undiluted solution chamber tied to the side and sucked by the undiluted solution pump
And a solution recovery side for introducing the solution, and a solution discharge side of the solution pump.
Connected to the stock solution storage tank and introduced through the stock solution recovery path
A stock solution return path for returning the stock solution to the stock solution storage tank,
When the stock solution is supplied by the pump,
Opening the liquid supply path and returning the undiluted liquid recovery path and undiluted liquid
When the stock solution is returned by the stock solution pump,
Open the stock solution recovery path and the stock solution return path, and
Means for controlling so as to close the stock solution suction passage and the stock solution supply passage .

[0007] Then filtration concentration method of the present invention, a filtration step to recover the filtrate pumping stock into the filtration device via the stock intake passage and stock pump and the stock solution supply line from a stock solution storage tank to the filtrate storage tank, from a stock solution chamber By sucking the undiluted solution from the undiluted solution chamber through the undiluted solution recovery passage, the undiluted solution pump, and the undiluted solution return line, the filtrate flowing back is used to peel off the filter cake from the filter medium and at least a part of the undiluted solution mixed with the filtrate into the concentrate storage tank. The backwashing step of collecting is alternately repeated and continuously performed. Further, the filtration and concentration method of the present invention is subject to filtration treatment.
A stock solution storage tank for storing stock solution, and a stock solution is supplied from the stock solution storage tank.
The stock solution chamber to be supplied and a filter medium are provided from the stock solution chamber.
And a filtrate chamber for receiving the filtrate filtered by the filter medium.
A filter, and a filtrate collection passage connected to the filtrate chamber.
A filtrate storage tank for storing the filtrate sent from the collecting path,
The supply and suction of the stock solution are alternately performed between the tank and the stock solution chamber.
And the liquid suction side of the
Connect the undiluted solution storage tank and suck the solution from the undiluted solution storage tank with the undiluted solution pump.
A stock solution suction passage for introducing the stock solution into the stock solution pump,
Connecting the liquid discharge side of the liquid pump to the liquid chamber,
The stock solution introduced through the solution suction passage is supplied to the stock solution in the stock solution chamber.
A stock solution supply path for feeding to the supply side and a stock solution supply side of the stock solution chamber
And the liquid suction side of the stock solution pump, and
A stock solution collecting passage for introducing the stock solution in the stock solution chamber sucked,
Connect the liquid discharge side of the liquid concentrate pump to the liquid concentrate storage tank, and
Return the undiluted solution introduced through the recovery path to the undiluted solution storage tank
The undiluted solution return path, and the undiluted solution is supplied by the undiluted solution pump.
Open the stock solution suction passage and the stock solution supply passage, and
Close the undiluted liquid collection path and undiluted liquid return path, and
When returning the undiluted solution by the undiluted solution pump,
And the undiluted solution return path is opened, and
Means for controlling the supply path to be closed.
From the tank via the stock solution suction passage, stock solution pump and stock solution supply passage
Filtration system that feeds undiluted solution to filter and collects filtrate in filtrate storage tank
Process, stock solution collection route, stock solution pump and stock solution return route from stock solution chamber
Backflow by aspirating stock solution from stock solution chamber through
Remove the residue from the filter medium with the filtrate and mix the residue.
Backwashing process to recover at least a part of the stock solution
Is repeatedly and alternately performed continuously.
You.

[0008]

According to the present invention, the backwashing process can be started only by switching the valve while the stock solution pump is operated to perform the filtration process, and the backwashing can be performed only by switching the valve. The process can return to the filtration process. Therefore, when the accumulation of the filter cake is small and the backwashing of the filter medium is easy, the operation of performing the backwashing for a short time and recovering the filtration efficiency is repeatedly carried out, thereby performing the continuous operation for a long time to perform the operation of the filter. It is possible to greatly improve the operation efficiency.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a filtration and concentration apparatus according to the present invention will be described with reference to FIG. In the figure, 1 is a stock solution storage tank, 2 is a filter, 3 is a filtrate storage tank, and 4 is a waste liquid tank. The filter 2 has a stock solution chamber 2b formed below and a filtrate chamber 2c formed above the partition plate 2a at the center. Further, a cylindrical filter medium 2d is suspended from the partition plate 2a, and the inside of the filter medium 2d communicates with the filtrate chamber 2c.

The primary side of the stock pump 5 is connected to the stock tank 1 by a stock suction line A, and the secondary side of the stock pump 5 is connected to the stock chamber 2b by a stock supply path B. An undiluted liquid return path C for returning the undiluted liquid to the undiluted liquid storage tank 1 is provided separately from the undiluted liquid supply path B. An undiluted liquid recovery path D for sucking the liquid in the undiluted liquid chamber 2b is provided on the primary side of the undiluted liquid pump 5. I understand. And these stock solution suction passage A, stock solution supply passage B,
The undiluted liquid return path C and the undiluted liquid recovery path D are electrically connected or closed by opening and closing the valves provided in the control unit 6.

The filtrate from the filtrate chamber 2c is sent to a filtrate storage tank 3 by a filtrate recovery path E, and the waste liquid is discharged from the bottom of the undiluted liquid chamber 2b by a drain path F to a waste liquid tank 4.
You can drop it. Reference numeral 7 denotes a waste liquid pump for sending the waste liquid in the waste liquid tank 4 to a waste liquid processing device (not shown).

In carrying out the filtration step of the undiluted solution in the filtration / concentration apparatus configured as described above, the control device 6
With the undiluted liquid suction path A and undiluted liquid supply path B opened and the undiluted liquid recovery path D closed, the drainage path F is closed and the filtrate recovery path E is closed.
Is opened, the stock solution pump 5 is operated, the stock solution in the stock solution storage tank 1 is fed into the stock solution chamber 2b, and the filtrate filtered by the filter medium 2d is stored in the filtrate chamber 2c from the pressure-accumulated state into the filtrate storage tank 3 via the filtrate collection path E. to recover. At this time, the undiluted solution return path C may be slightly opened so that a part of the undiluted solution returns to the undiluted solution storage tank 1 in order to adjust the filtration speed.

When the filtration process is continued, filter cake is deposited on the filter medium 2d and the filtration speed gradually decreases. Therefore, the concentrate return path C is squeezed to reduce the return amount of the concentrate, and the concentrate chamber 2b
At the same time as maintaining the filtration speed so as not to decrease. However, in the present invention, it is better to proceed to the next backwashing step before the amount of deposited cake becomes too large.

In the backwashing step of the present invention, while the above-mentioned filtration step is being continued, that is, while the stock solution pump 5 is operating, the stock solution suction passage A and the stock solution supply passage B are closed and at the same time the stock solution return passage C And the undiluted solution collection path D is opened, and the undiluted solution in the undiluted solution chamber 2b is sucked by the undiluted solution pump 5 and discharged into the undiluted solution storage tank 1. Then, the filtrate in the filtrate chamber 2c in the pressure accumulating state becomes the filter medium 2
d flows back to the stock solution chamber 2b, and the cake on the filter medium 2d is peeled off and falls into the stock solution in the stock solution chamber 2b. Then, a part of the filter cake is mixed with the stock solution and returns to the stock solution storage tank 1, but the lump cake is settled and deposited on the bottom of the stock solution chamber 2b.

In general, the time required for the filter cake on the filter medium 2d to be peeled off and settled is generally 30 seconds or less. Therefore, even if the settling of the filter cake is not completed, it is set in advance. After the elapse of the short backwashing time, the control device 6 opens the stock solution suction passage A and the stock solution supply passage B again, and closes the stock solution recovery passage D, thereby immediately returning to the filtration step.

The filtration step and the backwashing step can be continuously switched by simply switching the flow path while the stock solution pump 5 is operating. Stock solution chamber 2 while repeating
Filter residue gradually accumulates at the bottom of b. Therefore, in the present invention, the drainage path F is opened during the filtration step or when the operation of the stock solution pump 5 is stopped, and the waste solution containing the residue is discharged from the bottom of the stock solution chamber 2b to the waste liquid tank 4. Is about 10 seconds at most during the filtration process,
It hardly interferes with the filtration operation.

[0017]

According to the filtration / concentration method of the present invention, since the filtration and the backwashing can be continuously performed while the stock solution pump is operated, the waiting time for switching between the filtration and the backwashing is reduced. Is not necessary and the ratio of the actual filtration time to the operation time of the filter, that is, not only the operation efficiency of the filter can be significantly increased, but also the operation efficiency is greatly reduced even if frequent short-time backwashing is performed. The continuous operation time of the filter can be greatly extended,
Therefore, a large filtration capacity is exhibited as compared with the size of the apparatus. Furthermore, the filtration and concentration device of the present invention is a device suitable for performing the filtration and concentration method of the present invention, and the starting frequency of the stock solution pump can be significantly reduced, so that the power at the time of startup is reduced,
There is an advantage that the pump operation power supply does not need to have a large capacity and is economical and has a long life. In addition, since there is no need to introduce pressurized air during backwashing, it is possible to construct an economical device that does not require a pressure-resistant design. In addition, there is no need to apply an excessive filtration pressure, so that there is little damage to the filter medium. is there.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a filtration and concentration device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Undiluted solution storage tank 2 Filtration machine 2a Partition plate 2b Undiluted solution chamber 2c Filtrate chamber 2d Filter medium 3 Filtrate storage tank 4 Waste liquid tank 5 Raw liquid pump 6 Control device 7 Waste liquid pump A Raw liquid suction path B Raw liquid supply path C Raw liquid return path D Raw liquid recovery path E Filtrate Recovery path F Drainage path

Continuation of the front page (72) Inventor Saburo Yanagishita 4-5-5, Shinbo-cho, Chikusa-ku, Nagoya-shi, Aichi Prefecture (56) References Japanese Utility Model Publication No. 52-41584 (JP, U) US Patent 3862036 (US, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B01D 29/66

Claims (3)

(57) [Claims] 1. A stock solution for storing a stock solution to be filtered.
Storage tank, stock solution chamber to which stock solution is supplied from stock solution storage tank, and stock solution chamber
A filtrate which is provided with a filter medium further separated and filtered by the filter medium
And a filter provided with a filtrate chamber, and connected to the filtrate chamber via a filtrate recovery path, and fed from the filtrate recovery path.
A filtrate storage tank for storing the filtrate, and supply and suction of a stock solution between the stock solution tank and the stock solution chamber.
A liquid concentrate pump that alternately repeats the above, and connects the liquid suction side of the liquid concentrate pump with the liquid concentrate storage tank.
The undiluted solution sucked by the undiluted solution pump from the storage tank is
Connecting the undiluted solution suction passage to the pump, the liquid discharge side of the undiluted solution pump and the undiluted solution chamber,
The stock solution introduced through the solution suction passage is supplied to the stock solution in the stock solution chamber.
An undiluted liquid supply passage for supplying the undiluted liquid, a undiluted liquid supply side of the undiluted liquid chamber, and a liquid suction side of the undiluted liquid pump.
And feeds the undiluted solution in the undiluted solution chamber sucked by the undiluted solution pump.
Connecting the undiluted liquid collecting passage, the undiluted liquid storage tank with the undiluted solution of the undiluted liquid pump,
The stock solution introduced through the solution collection path is returned to the stock solution storage tank
The undiluted liquid return path, and the undiluted liquid suction path when the undiluted liquid is supplied by the undiluted liquid pump.
And opening the undiluted solution supply path, and the undiluted liquid recovery path and
Closing the undiluted solution return path and using the undiluted solution pump
When returning the solution, open the stock solution recovery path and stock solution return path.
And a means for controlling so as to close the stock solution suction passage and the stock solution supply passage . Wherein the filtering step of recovering the stock through the original stock solution suction passage from the reservoir and stock pump and the stock solution supply path to pump the filtered motor filtrate to the filtrate storage tank, stock recovery path and stock pump from a stock solution chamber A backwashing step of removing the filter cake from the filter medium with the filtrate flowing backward by sucking the stock solution from the stock solution chamber through the stock solution return path, and collecting at least a part of the stock solution mixed with the stock solution into the stock solution storage tank. Is carried out continuously alternately and repeatedly. 3. A stock solution for storing a stock solution to be filtered.
Storage tank, stock solution chamber to which stock solution is supplied from stock solution storage tank, and stock solution chamber
A filtrate which is provided with a filter medium further separated and filtered by the filter medium
And a filter provided with a filtrate chamber, and connected to the filtrate chamber via a filtrate recovery path, and fed from the filtrate recovery path.
A filtrate storage tank for storing the filtrate, and supply and suction of a stock solution between the stock solution tank and the stock solution chamber.
A liquid concentrate pump that alternately repeats the above, and connects the liquid suction side of the liquid concentrate pump with the liquid concentrate storage tank.
The undiluted solution sucked by the undiluted solution pump from the storage tank is
Connecting the undiluted solution suction passage to the pump, the liquid discharge side of the undiluted solution pump and the undiluted solution chamber,
The stock solution introduced through the solution suction passage is supplied to the stock solution in the stock solution chamber.
An undiluted liquid supply passage for supplying the undiluted liquid, a undiluted liquid supply side of the undiluted liquid chamber, and a liquid suction side of the undiluted liquid pump.
And feeds the undiluted solution in the undiluted solution chamber sucked by the undiluted solution pump.
Connecting the undiluted liquid collecting passage, the undiluted liquid storage tank with the undiluted solution of the undiluted liquid pump,
The stock solution introduced through the solution collection path is returned to the stock solution storage tank
The undiluted liquid return path, and the undiluted liquid suction path when the undiluted liquid is supplied by the undiluted liquid pump.
And opening the undiluted solution supply path, and the undiluted liquid recovery path and
Closing the undiluted solution return path and using the undiluted solution pump
When returning the solution, open the stock solution recovery path and stock solution return path.
To close the stock solution suction passage and the stock solution supply passage.
Control means for controlling the flow rate from the stock solution storage tank to the stock solution suction path.
The undiluted solution is pumped to the filter via the undiluted solution pump and undiluted solution supply path
The filtration process to collect the filtrate in the filtrate storage tank,
The solution chamber is connected via the solution collection path, the solution pump and the solution return path.
The filtrate from the filter medium with the filtrate flowing back by sucking the undiluted solution.
Peel off the residue and remove at least one of the stock solution mixed with the filter residue.
Backwashing process to collect the parts in the stock solution tank
A filtration and concentration method which is carried out continuously .