JP2001029715A - Liquid treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid treatment device wherein waste water is purified so that it can be used for recycling, or it is cleaned a sewage efferent standard value. SOLUTION: As a first process, rough sludge removal from waste water is carried out by a centrifugal separator 4, the waste water is heated by a heating tank 6, or vacuum-degassed by a vacuum degasifier, and solvent in the waste water is removed. As a second process, the waste liquid treated in the first process is micro-filtered by a flocculation type filter 14 which includes an adsorbent 19 composed of granulates or a powder formed by collecting crystalline fiber of magnesium, calcium, or aluminum borate. As a third process, the waste water micro-filtered in the second process is decolored by an ozone treater 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid purifying apparatus for recycling or purifying a coating wastewater to a sewage drainage standard value.

Conventionally, to purify coating wastewater to a sewage drainage standard value, first, a coagulant is added to the wastewater to precipitate and coagulate sludge in the wastewater, and the precipitate is subjected to pressure filtration by a press filter. And a second step of treating the clean water generated in the first step with bacteria while bubbling with air.

[0003]

The conventional apparatus is constituted by the above-described steps. In the first step, sludge is precipitated and aggregated by introducing a flocculant. However, this has caused a problem that a large amount of sediment is generated and the pressure filtration operation by the press filter becomes enormous. Furthermore, in the second step, since the treatment is carried out with bacteria, the treatment speed is slow, an enormous water tank is required, and there is a problem that a bad smell is generated.

[0004] The present invention has been made to solve the above-mentioned problems of the prior art.

The invention according to claim 1 is to remove rough sludge in the waste liquid in the first step, and to heat or vacuum degas the waste liquid to remove the solvent in the waste liquid. In the process of
The waste liquid treated in the first step is subjected to microfiltration by a coagulation type filtration device, and in the third step, the waste liquid microfiltered in the second step is ozone treated and decolorized, and the waste liquid is recycled. It is an object of the present invention to provide a liquid purification apparatus that purifies the liquid so that it can be used or purifies the sewage drainage standard value.

[0005]

[Means for Solving the Problems]

The invention of claim 1 is to remove rough sludge in the waste liquid, and to heat or vacuum deaerate the waste liquid,
The first step of removing the solvent in the waste liquid, and the second step of microfiltration of the waste liquid treated in the first step with a coagulation-type filtration device, and microfiltered in the second step This was realized by the third step of ozone treatment and decolorization of the waste liquid.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a detailed view of the ozone treatment apparatus of FIG. In the figure, for example, a coating waste liquid is poured into a waste liquid tank 1 from a waste liquid inlet 2. Pump 3 is a waste liquid tank 1
The waste liquid in the waste liquid is sent to the centrifugal separator 4, and rough sludge in the waste liquid is removed. In this case, the operation of the pump 3 is controlled by the level switch 5. The waste liquid from which the sludge has been roughly removed by the centrifugal separator 4 is sent to the heating tank 6 and heated by the heater 7, the solvent in the waste liquid evaporates and evaporates to the outside from the upper opening 8 of the heating tank 6. The waste liquid from which the solvent has been removed is sent into the dirty tank 11 of the purification tank 10 by the pump 9. In this case, the operation of the pump 9 is controlled by the level switch 12. The waste liquid in the dirty tank 11 is sent to the coagulation-type filtration device 14 by the pump 13, finely filtered, then sent to the clean tank 15 of the purification tank 10, overflows the partition 16, flows into the dirty tank 11, and is circulated and filtered. You. The coagulation-type filtration device 14 includes the first and second filtration layers 1.
Granular body or powdery body constituted by assembling crystalline fibers of magnesium, calcium, or aluminum borate provided between 7, 18 and the first and second filtration layers 17, 18 And an adsorbent 19 composed of The pump 20 sends the liquid in the clean tank 15 that has been finely filtered to the ozone treatment device 21. In this case, the operation of the pump 20 is controlled by the level switch 22. FIG. 2 is a detailed view showing one embodiment of the ozone treatment apparatus 21. In the figure, the liquid in the clean tank 15 is guided into the processing tank 24 through the inlet 23 and flows out of the processing tank 24 from the outlet 25. Yuzon tube 26
Is installed in the processing tank 24, and the low-pressure mercury lamp 27
It is installed in the Yuzon tube 26. Air pump 28
Sends air through the check valve 29 into the uzon tube 26 and irradiates the air with a low-pressure mercury lamp 27 to generate ozone. The generated ozone is supplied to the diffuser 30
Then, the liquid is guided from the lower part of the processing tank 24 into the processing tank 24 via the electromagnetic valve 31. Ozone introduced into the processing tank 24 is
In addition to decolorizing the liquid in the processing tank 24, the BOD,
Reduce COD. If a bleaching agent is injected into the processing tank 24, the decolorizing effect can be enhanced. The activated carbon device 32 performs a final treatment of the liquid that has been ozone-treated by the ozone treatment device 21. The liquid that has been subjected to the final treatment from the outlet 33 is subjected to, for example, sewage treatment or recycling. An ion exchange resin device may be provided after the outlet 33 to further improve the properties of the liquid to be recycled. If the activated carbon device 32 is not required, the outlet 3
4 plays the role of the outlet 33. Compressor 35
Is for compressing the solvent evaporated to the outside from the upper opening 8 of the heating tank 6 and sending the compressed solvent to the solvent recovery device 36. In the solvent recovery device 36, for example, water or a solvent of the same type as the mixed solvent The liquid has been injected, and the collection tank 37 has
A cage 38 having a porous body or a mesh state is provided on the bottom surface and the top surface. In the cage 38, a large number of solids 39 of, for example, about 3 mm square and 3 mmφ made of polypropylene are stored. The recycling tank 40 is separated from the solvent recovery tank 36 by a partition plate 41, and recycles the liquid flowing from the solvent recovery tank 36. Pump 42
Sends the liquid in the recycle tank 40 to the recycle port 43 and uses it as, for example, a solvent diluent. In this case, the pump 42 is controlled and operated by the level switch 44. When the liquid in the recycle tank 40 is disposed of, the liquid is discharged from the discharge port 46 through the activated carbon device 45.

Next, this operation will be described. Waste liquid tank 1
When, for example, a coating waste liquid is poured from the waste liquid inlet 2 and the liquid level reaches a predetermined position, the level switch 5 is operated to drive the pump 3 to send the waste liquid in the waste liquid tank 1 to the centrifuge 4. , To remove rough sludge in the waste liquid. The waste liquid from which the sludge has been roughly removed by the centrifugal separator 4 is sent to the heating tank 6 and heated by the heater 7, the solvent in the waste liquid evaporates and evaporates to the outside from the upper opening 8 of the heating tank 6. The centrifuge 4 and the heating tank 6
Thus, the first step is formed. In this embodiment, the heating tank 6 is provided after the centrifugal separator 4, but the centrifuge 4 may be provided after the heating tank 6. In the above embodiment,
Although the case of the heating tank 6 using the heater 7 has been described, a vacuum deaerator may be used instead. In this case, the first step is formed by the centrifuge 4 and the vacuum deaerator, and the centrifuge 4 is provided after the vacuum deaerator.
May be provided.

After confirming that the solvent is removed in the heating tank 6 and that the liquid level in the heating tank 6 is at or above a predetermined position, the pump 9 is driven by the level switch 12 and the waste liquid in the heating tank 6 is removed. Is sent into the dirty tank 11 of the septic tank 10. Further, the waste liquid in the dirty tank 11 is sent to the coagulation type filtration device 14 by the pump 13. The coagulation-type filtration device 14 includes first and second filtration layers 17 and 18 and first and second filtration layers 17 and 18.
An adsorbent 19 is provided between the second filtration layers 17 and 18 and is composed of a granular material or a powdery material formed by assembling crystalline fibers of magnesium, calcium, or aluminum borate. ing. The waste liquid sent into the coagulation-type filtration device 14 by the pump 13 first passes through the coarse first filtration layer 17,
It passes through the gap between the adsorbents 19. At this time, the distance between the fine particles in the waste liquid becomes equal to or less than a predetermined distance, an attractive force is generated, and the particles are aggregated with each other to form a large lump of about 300 times. These large agglomerates are captured by the second filtration layer 18, finely filtered, sent to the clean tank 15 of the purification tank 10, overflow the partition 16, flow into the dirty tank 11, and are circulated and filtered. You. After confirming that the liquid level in the clean tank 15 has been finely filtered in this way and that the liquid level in the clean tank 15 is equal to or higher than a predetermined position, the pump 20 is driven by the level switch 22 and the liquid in the clean tank 15 that has been finely filtered is It is sent to the ozone treatment device 21. This septic tank 10
The coagulation type filtration device 14 forms the second step.

The liquid in the clean tank 15 is guided from the inlet 23 of the ozone treatment apparatus 21 into the processing tank 24,
5 flows out of the processing tank 24. A uzon tube 26 containing a low-pressure mercury lamp 27 is installed in the processing tank 24,
The air pump 28 sends air into the uzon tube 26 through a check valve 29, and sends the air to the low-pressure mercury lamp 2.
Irradiation at 7 generates ozone. The ozone generated in this way is supplied to the diffuser 30 and the solenoid valve 3.
1, the liquid is guided from the lower part of the processing tank 24 into the processing tank 24 to decolorize the liquid in the processing tank 24 and to reduce the BO of the liquid.
D, COD is reduced. The ozone treatment device 21 forms a third step. Ozone treatment device 21
The liquid which has been subjected to the ozone treatment is subjected to a final treatment in an activated carbon device 32 and is subjected to sewage treatment from an outlet 33 or is recycled. Note that an ion exchange resin device may be provided after the outlet 33 to further improve the properties of the liquid to be recycled. Further, the activated carbon device 32 may be omitted, and sewage treatment or the like may be performed from the outlet 34.

The solvent evaporated from the upper opening 8 of the heating tank 6 to the outside is compressed by a compressor 35 and sent into a solvent recovery device 36. For example, water or a solvent of the same type as the solvent to be mixed is injected into the solvent recovery device 36, and a basket 38 having a porous body or a mesh state on the bottom surface and the top surface is installed in the recovery tank 37. In the basket 38, for example, a large number of solids 39 of about 3 mm square and about 3 mmφ made of polypropylene are stored. When the vapor containing the solvent sent to the lower part of the solvent recovery tank 36 passes through the gap between the solids 39 accommodated in the cage 38, the water filled in the solvent recovery tank 36 or the solvent of the same kind Only the vapor that comes into sufficient contact, dissolves in water or a similar solvent, and from which the solvent has been removed is released into the atmosphere from the upper opening of the solvent recovery tank 36. The water in which the solvent in the steam is dissolved, or the same type of solvent overflows the partition plate 41 and flows into the recycling tank 40,
When the liquid level becomes equal to or higher than a predetermined value, the pump 42 is driven by the level switch 44, and the liquid in the recycle tank 40 is sent out to the recycle port 43, and is used as, for example, a diluent for the solvent. Also, the liquid in the recycling tank 40 is
In the case of disposal, the discharge port 46 through the activated carbon device 45 is used.
To discharge. The compressor 35 and the solvent recovery device 36 form a fourth step.

As described above,

According to the first aspect of the present invention, in the first step, rough sludge in the waste liquid is removed, and the waste liquid is heated or vacuum degassed to remove the solvent in the waste liquid. In two steps, the waste liquid treated in the first step is subjected to microfiltration with a coagulation type filtration device, and in a third step, the waste liquid subjected to microfiltration in the second step is decolorized by ozone treatment. Since the waste liquid is purified so that it can be used for recycling, or the wastewater is purified to the sewage drainage standard value, the installation area can be made very small, and the waste liquid can be purified with a small and simple device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a liquid purification apparatus according to the present invention.

FIG. 2 is a detailed view of the ozone treatment apparatus shown in FIG.

[Description of Signs] 4: Centrifugal separator 6: Heating tank 7: Heater 10: Purification tank 11: Dirty tank 14: Coagulation type filtration device 15: Clean tank 17, 18: First and second filtration layers 19: Adsorbent 21: Ozone treatment device 35: Compressor 36: Solvent recovery device

[Procedure amendment]

[Submission date] September 28, 1999 (1999.9.2)
8)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Deleted

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C02F 9/00 502 C02F 9/00 502H 502R

Claims (1)

[Claims] A first step of removing rough sludge in the waste liquid and heating or vacuum degassing the waste liquid to remove a solvent in the waste liquid; A second step of microfiltration of the waste liquid obtained by a coagulation type filtration device, and a third step of ozone treatment and decolorization of the waste liquid microfiltered in the second step. Characteristic liquid purification device.