JPH0539621U - A bag filter equipped with auxiliary filter media. - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention provides a bag filter in which the filtration area is improved and the filtration life, that is, the ability to capture foreign substances is significantly improved while maintaining the function of the bag filter for capturing and containing foreign substances. The purpose is to provide. According to the present invention, an auxiliary filter medium is installed in the entire space in the bag filter at a density that does not offset by hydraulic pressure. The auxiliary filter medium has a large void ratio and particles of foreign matter to be removed. It is characterized by having a mesh larger than the diameter and being formed from a natural or synthetic non-woven fabric, a glass mat or cotton, which is coarser than the cloth mesh which is the material of the bag filter.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bag filter having a significantly improved filtration life, that is, a foreign substance capturing ability.

[0002]

[Prior Art]

 The bag filter is used when the liquid contains a high concentration of foreign matter and when the captured foreign matter is discarded or collected while being stored in the bag. Compared with cartridge filters such as filtration tubes used for the same purpose, this bag filter has advantages such as easy handling at attachment and detachment and low cost, so it is widely used throughout the industry. Has been done. For example, it is widely used for removing pigment crushed substances after milling such as ink and paint, removing raw material squeezing residue in the beverage industry, and removing cutting powder and polishing powder generated during various metal cutting and polishing processes. .

The bag filter is a bag made of cotton cloth, inorganic fiber cloth such as glass fiber, and synthetic fiber cloth such as polypropylene, polyester, nylon fiber and the like. This method of use is to let the liquid fall naturally, that is, to remove foreign matter in the process of letting the liquid flow into the bag bag by its own weight and leaching the liquid to the outside, and to apply pressure to the liquid to force it into a bag. In order to prevent the liquid from leaking from the upper part of the gufter, it is common to seal the liquid outlet on the upper part of the filter, let the liquid flow into the bag filter, and remove the foreign matter in the process of leaching the liquid to the outside of the bag.

As described above, the bag filter has an advantage over a general cartridge filter called a filter cylinder in terms of easiness of handling at the time of attachment / detachment, but on the other hand, compared with the cartridge filter. Since only the inner surface of the bag is an effective filter medium, the filtration area is very small.Therefore, if the trapped particle size and the filter medium pore size are similar, particles will be trapped in the pores. As a result, there was a drawback that the filtration life, that is, the ability to trap foreign substances was reduced. Therefore, there was a problem that the frequency of filter replacement increased. Since the bag filter captures foreign matter in the bag, if the bag is filled with a clogging prevention material, it will not be possible to store the foreign matter in the bag. There is no known idea of containing preventive materials.

[0005]

[Problems to be solved by the device]

 The present invention is intended to solve such a problem, and while maintaining the function of the bag filter for capturing and containing foreign matter, the filtration area is improved and the filtration life, that is, the ability to capture foreign matter is significantly improved. It is intended to provide an improved bag filter.

[0006]

[Means for Solving the Problems]

 The present inventor has conceived to utilize the space inside the bag filter in order to solve the big drawback of the bag filter, which has a smaller effective filtration area than the volume of the filter, that is, a small foreign matter capturing ability. That is, without filtering only on the inner surface of the bag, as far as possible, before the foreign matter in the liquid reaches the inner surface of the bag, it is a trapping mechanism of so-called loose filtration in the hollow part of the bag, interruption, inertia, diffusion, etc. It aims to expand the trapping capacity while maintaining the function of accommodating foreign matter by maximizing the use of the. As a means for this, the present inventor has proposed that the hollow space of the bag should have a density larger than the particle size of the foreign matter to be captured and coarser than the mesh of cloth, which is the material of the bag filter, due to the liquid pressure. The present invention has been achieved by finding that the above object can be achieved by filling the whole body, in other words, by forming the hollow portion of the bag into a three-dimensional structure. That is, according to the present invention, the auxiliary filter material is installed in the entire space inside the bag filter at a density that does not deviate by hydraulic pressure, and the auxiliary filter material has a large void ratio and is larger than the particle size of the foreign matter to be removed. It has a large mesh and is made of a natural or synthetic non-woven fabric, glass mat or cotton, which is coarser than the mesh of the fabric used for the bag filter.

[0007]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention, in which a bag filter 1 is internally provided with an auxiliary filter material 2 at a density that does not deviate by hydraulic pressure, and this is attached to a liquid pipe 3. Here is an example: The auxiliary filter material used in the present invention has a large porosity, has a mesh larger than the particle size of the foreign matter to be removed, and is a natural or synthetic non-woven fabric or a glass mat which is coarser than the mesh of the cloth used for the bag filter. Alternatively, it is made of cotton. In order to fill the auxiliary filter medium with a density that does not deviate by hydraulic pressure, for example, the above-mentioned nonwoven fabric or glass mat may be rolled into a cylindrical shape having a spiral cross section and filled. As shown in FIG. 1, in the present invention, the bag filter 1 is filled with the auxiliary filter material so as to have a three-dimensional structure. Therefore, when the liquid is introduced into the bag filter 1, the liquid The foreign matter 4 inside is blocked and adhered to the coarse mesh three-dimensional structure filter medium 2 by the action of inertia, diffusion, etc., and is captured in the bag filter 1. On the other hand, in the case of the conventional bag filter as shown in FIG. 4, the foreign matter 4 is captured only on the inner surface of the bag filter 1.

[0008]

[Action]

Next, a test example in which the filtration life and filtration efficiency were measured using the bag filter of the present invention and compared with the conventional bag filter will be shown. A bag filter 1 having the shape shown in FIG. 5 was produced from a nylon spunpond nonwoven fabric having a thickness of 0.28 mm, a weight of 100 g / m ² , and a fiber thickness of 1.5 denier, and this was used as a conventional bag filter in the test. A polypropylene spun-pond nonwoven fabric with a thickness of 2.4 mm, a weight of 200 g / m ² , and a fiber thickness of 30 denier was cut into 200 mm × 400 mm in the bag filter 1 described above, which was rolled into a cylindrical shape with a spiral cross section. As shown in FIG. 2, the bag filter 1 was incorporated into the bag filter 1 as the auxiliary filter material 2 to manufacture the bag filter of the present invention, which was used for the test. As the test powder, as test powder (foreign matter), JIS type 7 test dust was introduced into the city water at a rate of 1 g / min and introduced into the bag filter at a flow rate of 3 liters / min. ) And filtration efficiency were measured. Results are shown in FIG. As is clear from FIG. 3, there is no substantial difference in the filtration efficiency between the device of the present invention and the conventional product, but the time to reach the differential pressure of 1 kg / cm ² is about 60 minutes for the conventional product. On the other hand, the product of the present invention takes about 100 minutes, and it can be seen that the filtration life (capture ability) is significantly improved.

[0009]

【effect】

 As described above, according to the present invention, since the auxiliary filter material having a large porosity and which is not biased by the liquid pressure is installed in the bag filter, the bag filter is less likely to be clogged and the filter life ( (Capturing ability) is remarkably improved, and the function of accommodating foreign matter in the bag is maintained, resulting in a remarkably remarkable effect not seen at all in the conventional bag filter.

[0010]

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a state of filtering using a bag filter of the present invention.

FIG. 2 is a partially cutaway perspective view showing an embodiment of the present invention.

FIG. 3 is a graph comparing and measuring the filtration efficiency and the filtration life of the product of the present invention and the conventional product.

FIG. 4 is a cross-sectional view showing a state of filtering using a conventional bag filter.

FIG. 5 is a perspective view showing a conventional bag filter.

[Explanation of symbols]

 1 Bag filter 2 Auxiliary filter 4 Foreign material

Claims (1)

[Scope of utility model registration request] 1. A bag filter wherein the auxiliary filter material is installed in the entire space of the bag filter at a density that does not deviate by hydraulic pressure, and the auxiliary filter material has a large porosity and a mesh larger than the particle size of foreign matter to be removed. A bag filter, which is characterized in that it is formed from a natural or synthetic non-woven fabric, a glass mat or cotton, which is coarser than the mesh of cloth which is a material of the bag filter.