JPH06238111A - Method for washing filter casing of filter - Google Patents

Abstract

(57) [Abstract] [Purpose] A filter device in which a filter layer is formed by using a filter aid made of a fibrous material such as paper and a dispersant in a powder state. To provide a method for cleaning a filter cylinder that can be removed. [Structure] One to a plurality of filter cylinders 17 provided with a filter material 19 on the peripheral surface are provided, and a filter aid layer x is formed on the filter material 19, and floating small pieces p having a specific gravity smaller than that of water are supplied. Since the particles are made to be dense near the liquid surface, the floating small pieces p scrape off the filter auxiliary material layer x due to the liquid surface lowering accompanying the discharge of the liquid, and the removal of the filter auxiliary material layer x is efficiently performed. Can be applied to.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter device for cleaning a contaminated liquid such as a plating solution, and a method for cleaning the filter cylinder.

[0002]

2. Description of the Related Art In a tank having a supply port for a liquid to be treated, an outlet for a clean liquid and a liquid outlet, a fiber material is attached to a filter medium surface on the outer periphery.
One to a plurality of filter cylinders covered with a filter aid made of a dispersant such as a cloth material are hung vertically, and the inside thereof is communicated with the outflow port, so that the liquid to be treated is transferred to the filter aid and the filter material surface. A filter device is known in which the liquid to be treated is filtered by allowing the liquid to permeate and flow into the filter cylinder.

A filtering device for forming a fibrous layer of paper or the like on the filter material surface of this filter cylinder and using this as a filter material layer to filter the liquid to be treated which has permeated the filter surface is disclosed, for example, in Japanese Patent Laid-Open No. 55-55. -59818. Further, a filter material having a fibrous material such as paper and a powder material adhered to the surface of the filter material is disclosed in JP-A-62-4.
No. 5306.

[0004]

DISCLOSURE OF THE INVENTION The present invention resides in that the filter layer is formed using a filter aid made of a fibrous material such as paper and a dispersant in a powder state as described above. An object of the present invention is to provide a method for cleaning a filter cylinder of a filtration device, which enables effective cleaning of the filter cylinder.

[0005]

DISCLOSURE OF THE INVENTION The present invention is provided in a tank,
The specific gravity is smaller than that of water, innumerable floating pieces are dispersed, and as the liquid level in the tank is lowered by discharging the liquid from the liquid discharge port, the filter aid is scraped off by the floating particles. To do.

As the floating small pieces, various materials such as synthetic resin pieces, polygonal rubber pieces, large granular activated carbon and ceramic pieces are applied.

[0007]

The liquid containing the auxiliary material dispersed therein is supplied from the supply port into the tank, and the dispersion is passed through the filter material formed on the peripheral surface of the filter cylinder, whereby the filter auxiliary material in the liquid is applied to the surface of the filter material. Are deposited and a filter aid layer is formed. Then, when the liquid to be treated is supplied into the tank and the filtration operation is performed, the filtering action is caused by the filter medium and the filter aid layer, and the liquid to be treated becomes a clean liquid and is discharged from the outlet. At this time, floating pieces are supplied in advance into the tank. Since the floating particles have a low specific gravity, they are densely gathered at the liquid surface side position.

When this filtration operation is continued, a filter dust layer is formed on the surface of the filter aid layer, and as the layer thickness increases,
The pressure in the tank increases and the filtration efficiency decreases. Therefore, the supply port of the processing liquid is shut off and the liquid discharge port is opened to discharge the liquid in the tank. Along with this, the liquid surface descends, and the floating pieces that are densely packed on the liquid surface also descend together with the liquid surface, scraping the filter aid on the peripheral surface of the filter cylinder from the filter material surface. At this time, if the liquid surface is lowered while causing the inflow of air from the liquid discharge port and the discharge of the liquid alternately to cause a vertical wave (bubbling), the floating small particles are filtered. Is scraped off by rubbing it up and down, and good peeling efficiency can be achieved.

Also, at this time, an air supply source may be connected to the outlet to supply pressurized air into the filter cylinder.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the accompanying drawings. In FIG. 1, reference numeral 1 denotes a tank, and an arc-bulging lid frame 3 is attached to the upper surface of a tubular main body 2 having a collar formed on the upper portion thereof and fixed with bolts 4, and a lower portion of the tubular main body 2 is attached. A bottom frame 5 is fitted on the outer frame. A liquid flow path 6 is formed between the inner peripheral surface of the bottom frame 5 and the peripheral surface of the tubular body 2, and a supply port 7 communicating with the liquid flow path 6 is provided in the bottom frame 5. The supply port 7 communicates with an inflow conduit 9 which is opened / closed by a three-way switching valve 8. On the lower bottom of the bottom frame 5, an on-off valve 11
A liquid outlet 10 is provided which is controlled to be opened and closed by.

A locking projection 2 is formed on the inner surface of the upper portion of the tubular body 2.
a is formed, and the elastic projection cylinder 17 is provided on the locking projection 2a.
A mounting plate 13 having a plurality of connecting holes 12 inserted from above is mounted.

As shown in FIGS. 1 and 4, the filter cylinder 17 has a cloth material, glass fiber, tetron,
A filter material 19 made of a fiber material such as polypropylene is provided around the
By closely expanding the diameter of the coil 18 at one end to use this as the rim 20, and disposing a resin plug material 21 such as polypropylene at the other end, and heating and welding the filter material 19 under the same. It is sealed. Thus, the stretchable filtration cylinder 17 having one end opened and the other end closed and having elasticity in the longitudinal direction is configured. The filter cylinder 17 has a length of 500 mm and an outer diameter, for example.
A relatively thin one such as 12 mm can be applied. The number of the filter cylinders 17 can be set to one to several tens corresponding to the required processing capacity.

The filter cylinder 17 is inserted into the connecting hole 12 from above, and the mouth edge 20 is hung from the periphery of the connecting hole 12 to be suspended. A holding plate 15 having a through hole 14 which is vertically aligned with the connecting hole 12 is attached to the mounting plate 13 and is connected to each other by a bolt 16.

A liquid reservoir 23 for clean liquid is formed between the holding plate 15 and the lid frame 3 and communicates with an outlet 24 provided at the upper end of the lid frame 3. That is, the outlet 24 is connected to the connecting hole 1
2, It will connect with the inside of each filter cylinder 17 through the through hole 14. Further, on the upper side wall of the tubular body 2, there is provided a liquid outlet 30 which also serves as an air vent.

Next, the supply port 7, the outlet 24 and the liquid outlet 3
The tube connection of 0 will be described. The outflow port 24 communicates with a treated tank (not shown) for collecting the clean liquid through an outflow pipe line 25. A three-way switching valve 26 that controls the flow of the clean liquid in the outflow conduit 25 and a three-way switching valve 2 that controls the switching to the air supply source 27 that generates pressurized air.
8 are provided.

The supply port 7 communicates with a stock solution tank 40 such as a plating solution tank through an inflow conduit 9. A pump 34 is interposed in the inflow conduit 9, and a conduit 39 communicating with the outlet of the auxiliary material liquid tank 35 is connected to the suction side of the pump 34 via a three-way switching valve 8. Further, the other supply port of the three-way switching valve 8 is connected to the stock solution tank 40.

The auxiliary material liquid tank 35 is provided with a supply cylinder 36 in which a stirring blade 38 is installed, and communicates with the auxiliary material liquid tank 35 through an opening / closing valve 37. Further, the auxiliary material liquid tank 35 is inserted with the mouth end of a conduit 41 connected to the outflow conduit 25 via the three-way switching valve 26, and a bypass conduit 32 in which a liquid discharge port 30 and an opening / closing valve 31 are also interposed. Is inserted so that the liquid from the outflow port 24 and the liquid discharge port 30 can flow in.

In addition, an infinite number of floating small pieces p having a specific gravity smaller than that of water are supplied into the tank body 1a, and the small pieces p are concentrated near the liquid surface due to the difference in specific gravity. As the floating small pieces p, various materials such as synthetic resin pieces, polygonal rubber pieces, large granular activated carbon, and ceramic pieces are applied. As a concrete shape,
Various shapes such as a polygonal shape and a short cylindrical shape can be applied. In the above-mentioned configuration, various operating modes will be described below.

[Formation of Filter Aid Material Layer] A process of forming the filter aid material layer x on the filter material 19 of the filter cylinder 17 in the above structure will be described. First, the paper is supplied into the supply cylinder 36 to which the liquid has been supplied in advance, the stirring blade 38 is rotated, and the paper is cut into the fibrous shape and dispersed in the supply cylinder 36. Next, a powdery material formed by mixing one or more kinds of various materials such as activated carbon, silicon earth, coal, and metal powder is mixed. This amount is, for example, about 50 g for 20 liters of liquid. Furthermore, the stirring blade 3
Rotate 8 and stir with fiber in solution. By mixing this powdery material, the fibers are further cut into smaller pieces and dispersed in the liquid.

The dispersion liquid is opened by opening the on-off valve 37,
The auxiliary material liquid tank 35 is transferred to the main body. Next, the changeover valve 26 of the outflow pipe 25 is changed over so that the outflow port 24 is connected to the auxiliary material liquid tank 3
After communicating with the No. 5 side, the switching valve 8 is switched to the auxiliary material liquid tank 35 side, the pump 34 is driven, and the dispersion liquid is caused to flow from the supply port 7 in the circumferential direction of the through hole 6. The dispersion liquid swirls through the through hole 6 and descends, forming a vortex and flowing into the tank body 1a. The reason why such a vortex flow is generated is that the filter aid such as the fibrous material and the powdery material is uniformly attached to the outer peripheral surface of the filter material 19.

In the dispersion liquid, a filter aid consisting of fibers and powders is attached to the filter medium 19, and the outflow conduit 24 is discharged from the outlet 24.
5 is collected in the auxiliary material liquid tank 35 via the supply port 7
After passing through the circulation path flowing out of the filter medium 19, it permeates the filter medium 19 again.
By this circulation, the filter aid of the dispersion liquid adheres to the peripheral portion of the filter medium 19, and the liquid in the aid liquid tank 35 becomes clean, thus the filter medium 1
As shown in FIG. 2, the filter aid material layer x is formed on the nine circumferences. The filter aid material layer x has a substantially uniform thickness along the vertical direction of the filter material 19, and the powdery material is dispersed in the fibers to have a high density. Therefore, good filtration performance can be obtained in the filtration step described later.

To further increase the density of the filter aid material layer x,
After the formation of the filter aid material layer x is completed, only the powdery material is then supplied from the opening of the supply cylinder 36 to be dispersed in the liquid, and the filter material 19 is permeated and circulated as described above. As a result, the powdery layer y is attached to the peripheral surface of the filter aid layer x, and the particles press the filter aid layer x by the action of the pump 34 described above. Therefore, the filter aid material layer x is compressed from its peripheral portion, and becomes more dense as shown in FIG.

[Filtration Operation] After the formation of the filter aid layer x,
By switching the switching valve 26 to the original position, the outlet 24
Is communicated with the treatment tank, the switching valve 8 is switched, the supply port 7 is communicated with the contaminated liquid tank, the filter aid layer x is permeated, and the filtration treatment is performed.

That is, by controlling the switching valves 8 and 26,
When the supply port 7 is communicated with the stock solution tank, the outlet 24 is communicated with the treated tank side, and the pump 34 is driven, the process liquid flows from the tank body through the supply port 7 and the through hole 6. The processing liquid flows into 1a. This processing liquid is used in each filter cylinder 17
It permeates the filter aid layer x and the filter medium 19 into the inside, and receives the filtering action to become a clean liquid. Filter medium 1 of the filter cylinder 17
The clean liquid filtered by 9 flows out from the outlet 24 through the outflow pipe 25 to the processing tank side. During this filtering operation, the filter cylinder 17 is contracted by the pressure from below as shown in FIG.

[Simple backwashing] When the filtration work is continued,
A filter dust layer z is formed on the surface of the filter medium 19, the filter medium 19 is clogged, and the water pressure in the tank 1 rises. This increase in pressure is detected by a known pressure detecting means, and the next simple backwashing process is started.

This simple backwash is to regenerate the filter aid layer x without consuming the filter aid. First, the operation of the pump 34 is stopped, the switching valve 8 is closed, and the liquid outlet 30 is discharged. The on-off valve 31 of the bypass passage 32 which is in communication is opened, and further the switching valve 28 is switched so that pressurized air having a gauge pressure of 1 to 2 kg / c〓 is communicated with the outlet 24 from the air supply source 27 for several seconds. Next, the switching valve 28 is closed, and the liquid discharge port 30 is left open for several tens of seconds.

As a result, the cleaning liquid in the liquid reservoir 23 and the filter cylinder 17 is discharged from the filter medium 19 due to the pressure thereof. At this time, since the internal pressure of the filter cylinder 17 becomes higher than the surrounding water pressure, the coil 18 that has contracted during the filtering process is not shown in FIG.
It stretches vertically like b. Therefore, the filter medium 1
The filter aid material layer x formed on the circumferential surface of 9 is cracked and peeled off together with the filter dust layer z, and is cleaned. Further, the liquid flowing out from the filter medium 19 is supplied from the liquid outlet 30 to the auxiliary liquid tank 35.
Discharged to the side. At this time, a shielding net 30a that prevents the floating small pieces p from permeating is attached to the above-mentioned 30 so that the floating small pieces p are not discharged.

The pressure applied to the filter aid layer x is released even if the operation of the pump 34 is stopped, and the liquid supply is stopped and allowed to stand. The filter dust adhering to is peeled off by its own weight.

After this simple backwash, the liquid outlet 30 is shut off, the above-mentioned filter aid layer is formed, and the filter aid layer x is formed again on the peripheral surface of the filter medium 19.

[Authentic backwashing] The simple backwashing causes regeneration of the filter aid layer x without exhausting the filter aid, but since dust is circulated without being discharged, pure filter aid is obtained. The material layer x cannot be regenerated. Therefore,
Perform the following full-scale backwash as appropriate. That is, the operation of the pump 34 is stopped, the open / close valve 8 and the open / close valve 26 are closed, the open / close valve 31 of the pipe line 8 communicating with the liquid discharge port 30 is opened, and the changeover valve 28 is changed over to change the air supply source 27. Then, pressurized air having a gauge pressure of about 1 to 2 kg / c〓 is communicated with the outflow port 24 for several seconds, and then the on-off valve 11 is switched to open the liquid discharge port 10 serving as the drain port.

As a result, the liquid in the liquid reservoir 23 and the tank body 1a is discharged from the liquid discharge port 10 due to its pressure.

When the liquid level in the filter cylinder 17 becomes lower than the mounting plate 13 by this discharge, the pressurized air also acts on the liquid level of the tubular main body 2 to cause the liquid level drop. Along with this liquid level drop, the innumerable floating small pieces p that are densely packed near the liquid level also descend. Then, as shown in FIG.
Of the filter aid layer x formed on the peripheral surface of the
It is scraped off with. At this time, the liquid outlet 10
Is opened, the liquid level is lowered while causing an inflow and outflow of air from the liquid discharge port 10 and liquid is discharged alternately, and the floating small pieces p are filtered. The auxiliary material is rubbed up and down and scraped off, and good peeling efficiency can be achieved.

On the other hand, as the liquid level drops, pressure air is ejected from the inside of the filter cylinder 17 through the filter medium 19 toward the liquid level side, and the coil 18 contracted during the filtering process extends vertically. Therefore, in combination with the scraping action by the floating pieces p, the filter aid layer x formed on the peripheral surface of the filter medium 19 is cracked and peeled off together with the dust layer z, and the cleaning is effectively performed. It In particular, the upper portion of the filter cylinder 17 is fixed to the mounting plate 13, and the degree of extension of the coil 18 is smaller than that of the lower portion, so that the scraping action by lowering the floating piece p is effective.

In addition, as shown in FIG. 5, the filter cylinder 17 may be one in which a thick filter medium 51 formed by winding a fiber material is provided on the outer periphery of the cylindrical holding frame 50 and the inside thereof is covered. Even with such a configuration, as shown in the figure, the filter medium 51
A filter aid material layer x may be formed on the peripheral surface of the.

The switching valves 8, 26, 28 and the on-off valves 11, 31 described above can each be constituted by electromagnetic valves, and the opening / closing control of each valve is related to the pressure detecting means provided in the tank 1. Thus, each of the above steps can be performed automatically.

[0036]

As described above, according to the present invention, one to a plurality of filter cylinders provided with a filter material on the peripheral surface are provided, and the filter aid material layer x is formed on the peripheral surface of the filter material. Since the smaller floating pieces p are supplied to be concentrated near the liquid surface, the floating small pieces p scrape off the filter aid material layer x due to the liquid level lowering accompanying the discharge of the liquid. There is an excellent effect that the material layer x can be efficiently removed.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a filtration device to which the present invention is applied.

FIG. 2 is a partially enlarged vertical side view of a filter medium 19 showing formation of a filter aid layer x.

FIG. 3 is a partially enlarged vertical side view of a filter medium 19 showing formation of a powdery layer y.

FIG. 4 is an enlarged vertical cross-sectional side view showing the separating operation of the filter aid material layer x.

5 is a vertical cross-sectional side view showing another configuration of the filter cylinder 17. FIG.

[Explanation of symbols]

 1 Tank 6 Inlet Hole 7 Supply Port 10 Liquid Discharge Port 17 Filter Cylinder 18 Coil 19 Filter Material 24 Outlet x Filter Aid Layer p Floating Pieces

Claims (1)

[Claims] 1. A fiber material is provided on a filter medium surface of an outer periphery in a tank provided with a supply port for a liquid to be treated, an outlet for a clean liquid and a liquid outlet.
In a filter device in which one to a plurality of filter cylinders covered with a filter aid made of a dispersant such as a cloth material are vertically provided, and the inside of which is communicated with the outlet, in the tank, a specific gravity is higher than that of water. Even a small number of small floating particles are supplied to make them close to the liquid surface,
A method of cleaning a filter cylinder of a filter device, wherein the filter aid is scraped off by the floating particles as the liquid level in the tank is lowered by discharging the liquid from the liquid discharge port.