JPS62289209A - Precision filter device - Google Patents

Abstract

PURPOSE:To obtain a filter device of high performance and a filter medium layer easy to wash by compressing spirally the filter layer formed by an assembly of fascicular fibers consisting of a specified threads as a filter medium, and filtrating thereby. CONSTITUTION:A liquid to be filtrated is supplied to fill up a filter tower 1 through a supply pipe 17 of said liquid, and then the filter layer 4 in which the assembly of fascicular fibers consisting of nontwisted threads made of curled shrinkage treatment threads of long fibers of 5 or less denier single thread size is used as the filter medium and is fixed to a filter medium fixing plate 2 connected to a rotating axis 21, is rotated by a filter medium rotating device 5 and is spirally compressed by a filter medium vertically driving device 6. Then, the liquid to be filtrated is continuously supplied in the tower 1 through the supply pipe 17 of said liquid. And colloidal particles in the liquid to be filtrated are caught by the filter medium of the filter medium layer 4, and the filtrate becomes water of good quality and is discharged through a filtrate discharge pie 13. When the pressure in the tower 1 is increased to a specific pressure, a washing liquid of a specific amount is supplied to the tower 1 from one end of a washing liquid supply pipe 11, and the filter medium layer 4 is automatically washed.

Description

[Detailed description of the invention] 3. Detailed description of the invention (industrial application field) The present invention utilizes fibers used to remove solid particles suspended in water (hereinafter referred to as colloid particles). The present invention relates to a precision filtration device that is high-performance and has a filter medium layer that is easy to clean.

(Prior Art) Conventionally, filtration media using fibrous structures used for the purpose of filtering colloidal particles in water include sheet-like materials or sheet-like materials called so-called filter cloths made of nets or woven fabrics. A cylindrical product, a spongy fiber laminate made by depositing short fibers and melting or integrating them with a binder, a laminate made by winding short fiber spun yarn into a cylindrical shape, or a membrane filter made into an accordion shape. It is known to be rolled.

Among these filtration media, filter cloth, membrane filter-9
In the case of filtration using a cylindrical fiber filter, the thickness of the filter layer is too thick, so the filtered material is trapped on the surface of the filter layer.
Surface filtration becomes dominant.

It is unsuitable for microfiltration aimed at processing large amounts of dilute) Δ suspensions containing colloidal particles. On the other hand, in conventional sponge-like fiber laminates, deep filtration in which colloidal particles are trapped inside the filter layer is dominant and is suitable for precision filtration, but since the filter media pores are fixed, they cannot be captured by normal cleaning methods. It was difficult to remove the substance by separation of Ml, making it difficult to recycle the filter media.

Further, as a conventional method for filtering with a filter layer in which fibers are deposited, an invention disclosed in JP-A-57-156012, for example, is known. For this invention.

Although it is possible to wash the filter media, since short fibers are used, the disadvantage is that the short fibers often get mixed into the treated water, and in terms of filtration performance, the colloidal particles that can be captured are only visible in the turbidity display. 5mg//! It was about.

In order to solve these problems, the present inventors.

Previously, we proposed a precision filtration device for capturing colloidal particles in water in Japanese Patent Application No. 59-215735. This device is.

Unlike conventional products, it has the ability to capture colloidal particles in a sufficient amount.

(Problems to be Solved by the Invention) However, the above-mentioned invention has the disadvantage that cleaning efficiency is poor due to the equipment, and re-adhesion to the fiber filter medium occurs during cleaning.

Cleaning efficiency deteriorates. Furthermore, in order to use it as a pretreatment for reverse osmosis membranes, UF (ultra filter) membranes, etc., it was necessary to further improve the colloid particle removal rate.

The present invention solves the above problems by providing highly accurate treated water with improved removal rate of colloidal particles, and by providing an apparatus that can be easily cleaned even when fibers are clogged with trapped substances. It is to provide.

(Means for Solving the Problems) In order to solve these problems, the inventors of the present invention have conducted extensive research and found that cleaning the filter medium is easy.

Moreover, the present invention has been achieved in which the removal rate of colloidal particles is improved.

In other words, the filtration device of the present invention is a device for filtering fine particles suspended in water using countless fibers as a filter medium, and the single fiber is a tow-like fiber made of untwisted long fiber crimped yarn of 5 deniers or less. A filter media rotation device in which a fiber aggregate is used as a material and fixed to a filter media mounting plate (2) connected to a rotating shaft 12+1 to form a filter media layer (4), and this filter media layer is further connected to the filter media mounting plate (2). (5) and a filter medium elevating drive device (6) connected to a filter medium compression plate (3).

First, the long fibers that make up the filter layer (4)! 8 shrink processed yarn.

Single yarn fineness is preferably 5 denier or less, particularly 5-0.3
Denier is preferred. When the single fiber fineness exceeds 5 denier, the space between adjacent fibers becomes large, resulting in a decrease in performance as a filter medium. What is the lower limit of single yarn fineness?

Although there is no particular restriction, if the yarn is less than 0.3 denier, even if the yarn is crimped, the fineness is too small, so the crimpability is low, and the characteristics of deep filtration cannot be utilized.

Only the same filtration effect as with uncrimped filaments can be obtained.

1. Thermoplastic synthetic fibers are preferably used as the fibers for the crimp-processed yarn, since the crimpability of the yarn is required to be maintained almost permanently in the wood aperture device. As a method for manufacturing crimped yarn, a method generally called bulk processing can be adopted, and specifically, any method such as anti-phosphorus removal, pressing method, rubbing method, air injection method, etc. may be manufactured.

As the thermoplastic synthetic fiber, polyester, nylon, polyolefin, etc. are preferably used in terms of performance such as strength, dehydration properties, and hydrophobicity. If filaments that are not crimped are used, continuous straight water channels will be formed between the fibers of the filter layer, making it difficult to capture colloidal particles. Furthermore, even if the particles are captured, the filter layer becomes planar and single-surface filtration is dominant, leading to rapid clogging and increased cleaning frequency.

The reason why long fiber yarn is used in the present invention is as follows.

This is to facilitate cleaning of the filter medium and to prevent fibers from being mixed into the treated water during cleaning of the filter medium.

Further, the above-mentioned fibers are used in an untwisted state without being twisted. Twisting it will increase the cost.

1. The filament was crimped to make it bulge.
．． This is because the yarn becomes compact due to this effect, and the voids between the fibers cannot be made large.

(Example) An embodiment of the present invention will be specifically described below with reference to the drawings.

FIG. 1 shows the overall configuration of the apparatus, FIG. 2 is a front view of the filter medium mounting plate, and FIG. 3 is a plan view thereof. In FIG. 1, reference numeral 1 denotes a filter tower having a circular cross section, and a filter media rotation device 5 that can be rotated in forward and reverse directions is provided at the top of the filter tower.A rotating shaft 21 is connected to this filter media rotation device 5, making one rotation. A filter medium mounting plate 2 is connected to the tip of the shaft 21. Also, the pressure switch 8. Air bleed pipe 9 and its opening/closing valve 10. Cleaning liquid supply pipe 11 and its on/off valve 12. Filtrate extraction pipe 13 and its opening/closing valve 14. Siphon cutting tube 15
and an on-off valve 16 are provided. Furthermore, at the bottom of the filter tower, there is a filter media lifting device 6. 8 lifting rods 22 that connect the drive device and the filter medium compression plate 3. Filtrate supply pipe 17 and its opening/closing valve 18. A backwash water outlet pipe 19, an on-off valve 20 thereof, and a filtration tower support 7 are provided.

Next, a method for forming a filter medium will be explained with reference to FIGS. 2 and 3. First, a fiber filter medium made of non-twisted long fiber crimped yarn is attached to the filter medium, and the thickness of the overlayer is 3001000+ nm.
Fill it so that it is. To attach the filter medium layer 4 to the temporary filter medium attachment plate, insert the slit 2 of the filter medium attachment plate as shown in Figure 3.
4 and hang the filter medium as shown in Figure 2. The method of filling the filter medium is to compress the filter medium with the filter medium compression plate without rotating the filter medium mounting plate, thereby forming a uniform filter medium layer, which allows filtration to be performed by rectifying the flow without short-passing the liquid to be filtered. .

Next, each operation of the device will be explained based on the drawings.

First, close the on-off valves 10, 12, and 20.

The on-off valves 14, 16, and 18 are kept open and the filtrate is supplied to the filtrate supply pipe 1 by a supply water pump (not shown).
From step 7, water is supplied into the filtration tower until it is full. Next, the filter medium layer 4 is compressed by the filter medium lifting/lowering drive device 6, and the filter medium layer 4 is rotated by the filter medium rotating device 5 and compressed in a spiral shape. This is because the filter medium layer 4 formed in this manner has a significantly larger liquid passage contact area and contact time per unit volume of filter medium than conventional ones.

- Can stop liquid short circuits called short paths.

Thereafter, the liquid to be filtered is filtered. In this case, the on-off valves 10, 12.20 are closed, and the on-off valves 14, 16.18 are left open, and the liquid to be filtered is supplied from the feed pipe 17 into the filtration tower 1. The liquid to be filtered is continuously supplied to the filtrate. This will cover
The colloid particles during filtration are captured by the filter medium of the filter medium layer 4 and are taken out from the filtrate extraction pipe 13 as a filtrate with good water quality. Note that the filtration capacity can be adjusted to obtain the desired filtration water quality depending on the degree of compression of the filter medium layer 4. Furthermore, the thickness of the filter medium layer 4 also affects the filtration efficiency and filtration accuracy, so it can be set arbitrarily as necessary, but it should be taken into consideration the regeneration of the filter medium after washing, the quality of filtrate water, and the short path of the filtrate, which will be described later. Generally, 100 mm or more is desirable.

Although the liquid to be filtered is filtered as described above, many colloid particles adhere to the filter medium of the filter layer 4, causing clogging and increasing the pressure within the filter tower 1.

Then, the pressure switch 8 detects that the pressure inside the filtration tower 1 has increased to a constant pressure.

Then, the on-off valves 14, 16, and 18 are automatically closed.

On the other hand, the valve 12.20 is opened and the cleaning liquid is supplied to the cleaning liquid supply pipe 1.
A fixed amount of water is supplied into the filtration tower 1 from one end of the filtration tower 1.

The filter layer 4 is automatically cleaned. Namely.

The filter medium that has captured the colloidal particles is rotated by the filter medium rotation device 5 at the top of the filter tower, and at the same time the filter medium is removed from the filter column by lowering the filter medium lifting drive device 6 to release the compression of the filter medium. do. At this time, it is preferable to extract the liquid to be filtered when the tip of the released filter medium is submerged by about 100 to 150 mm. Thereafter, the filter medium elevating drive device 6 is moved up and down and the tip of the filter medium layer is struck by the filter medium compression plate 3 to be washed. During this cleaning, it is desirable that the filter media rotating device 5 be rotated in the forward or reverse direction at regular intervals. This removes colloidal particles trapped in the filter medium. After cleaning the filter media layer.

Close the on-off valves 12 and 20 again, while the on-off valves 14 and 16
．． 18 is opened and the liquid to be filtered is supplied from the liquid to be filtered supply pipe 17 to the J12 filter tower 1 until it is full of water, and as described above, a material layer is formed and filtration is performed.

This cleaning method is a continuous water flow method, but a hatch water flow method described below may also be used (the method may be selected as appropriate depending on the degree of dirt).

In the hatch water flow system, after filtration is completed, a first wash is performed using a certain filtered liquid in the filtration tower, and the washed liquid is discharged to the outside of the system through a backwash water outlet pipe 19 and an on-off valve 20. After that, freshly filtered water is passed through the cleaning liquid supply pipe 11 using a backwash water supply pump (not shown), and the on-off valve 12 is opened, and the water is poured in to the set position and washed in the same manner as in the continuous water flow method. *I do. By repeating this operation 2 to 3 times, it is possible to perform cleaning with a high cleaning effect similar to the continuous water flow method, and to reduce the loss of cleaning water.

Incidentally, in the embodiment, the cleaning is performed using the pressure switch 8, but it goes without saying that the cleaning may be performed by setting a timer.

As mentioned above, this filtration device has extremely low filtration pressure.
For example, the filter layer is 200 mm and the compression rate is 15%.

When filtration is performed at a flow rate of LV-50i/min using a filter layer with a porosity of 93%, the initial pressure is 0.1 kg/cr.
It was below A. In addition, the porosity in the filter medium layer is measured.

It is determined from the relationship between the apparent specific gravity S + (g/Cal+) of the fiber mass and the specific gravity S 2 (g/cl) of the fiber.

Because the initial pressure is so low, the power of the water pump is extremely low, making it an excellent filtration device from an energy-saving perspective. As a result, compared to conventional filtration devices, it was possible to increase the filtration speed, reduce the installation area, and provide good filtration performance. Furthermore, in the present invention, filtration is performed in an upward flow, which is advantageous in terms of filtration efficiency and cleaning efficiency, which is also important for high-performance filtration.

This was achieved for the first time by using thin fibers of 5 deniers or less as the filter material.Although it depends on the properties of the colloid particles in the filtered liquid, the cleanliness of the liquid after filtration is 1. /e or less. Therefore, a water quality with a turbidity of 0.1 .mu./l can be fully achieved if conditions are selected.

(Effects of the Invention) The filtration bag of the present invention allows continuous high-precision filtration without causing large water flow resistance.

Moreover, QT2, which was considered difficult in the field of normal precision filtration,
The material can be easily cleaned and can be used repeatedly for a long period of time.

Therefore, it can be used as a pretreatment device for reverse osmosis membranes, ion exchange membranes, UF membranes, etc.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is an overall vertical sectional view, FIG. 2 is a front view of a filter mounting plate, and FIG. 3 is a plan view of the filter mounting plate. 1-Filtering tower 2-Filtering medium mounting plate 3-Filtering medium compression plate 4-Filtering medium layer 5-Filtering medium rotation device 6-Filtering medium elevating drive device 7-Filtration tower support 8-Pressure switch 9-Air vent pipe 10-On-off valve 11 -Cleaning liquid supply pipe 12-On-off valve 13-
i1 Filtrate extraction pipe 1.1 - On-off valve 15 - Siphon cut-off pipe 16 - On-off valve 17 - Filtered liquid supply pipe 18 - On-off valve 19 - Backwash water extraction pipe 20 - On-off valve 21 - Rotating shaft 22 - Field drop Core rod 23 - Rectifying holes for filter media mounting plate 24 - Filter media mounting plate slit.

Claims (3)

[Claims] (1) A device that filters fine particles suspended in water using countless fibers as a filter medium, in which a tow-like fiber aggregate made of untwisted long fiber crimped yarn with a single filament fineness of 5 deniers or less is used as a filter medium. Filter media mounting plate (2) connected to rotating shaft (21) as
A filter media rotation device (5) is fixed to the filter media to form a filter media layer (4), and the filter media rotation device (5) is connected to the filter media mounting plate (2), and a filter media lifting device (6) is connected to the filter media compression plate (3). A precision filtration device configured to compress. (2) Thickness in uncompressed state is 300mm or more and 1000mm
The precision filtration device according to claim 1, wherein the filter medium layer is compressed to a thickness of 100 mm or more and 400 mm or less. (3) The precision filtration device according to claim 1, wherein the filtrate supply pipe (17) is provided below the filter medium layer (4).