JP2013193080A - Bag filter medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bag filter medium capable of improving collection efficiency for dust within dust and exhaust gas, and having a large dust collecting capacity and a long service life as a result of withstanding dust sweeping off of the bag filter media, that is, expansion and contraction of the filter media.SOLUTION: An ultrafine fiber having a fiber diameter of 0.01 to 0.5 μm is laminated on or mixed with non-woven or woven cloth made of synthetic fiber or glass fiber or natural fiber, etc., and a filter medium in which an ultrafine fiber is formed integrally with non-woven or woven fabric is folded cylindrically or in a zigzag pattern to be pleated so that the circular or envelop-formed bag filter medium can be obtained for regeneration by sweeping off.

Description

  The present invention relates to a bag filter medium in which collected dust adhering to the surface is removed and regenerated.

  Conventionally, bag filters have been used in a wide range of fields, such as incinerators and the removal of dust from clean exhaust gas discharged from various factories such as electric furnaces and converters in the steel and steel industry.

Normally, bag filters are used in a wide range of fields such as preventing dust from being exhausted into the bag filter body by collecting dust exhaust gas discharged from various factories, collecting dust with the bag filter medium, and exhausting it into the outside as clean air. ing.
The bag filter regenerates the collecting surface of the bag filter medium while removing dust, etc., so compressed air such as backwash air or pulse jet is ejected from the surface of the filter medium opposite to the dust collecting surface. The dust collection surface is removed, the dust collection surface is regenerated, and the dust collection operation is resumed.

  However, since the compressed air sent to the dust collection surface does not apply pressure evenly in the bag filter body, only a part of the collected dust can be effectively peeled off. Dust adheres to the collecting surface, and the above-mentioned removal operation must be repeated again, so that it cannot perform a sufficient dust collecting function, and the dust collection rate is insufficient, and the specific resistance of the filter medium is high. In addition, there is a problem that the life of the bag filter medium is shortened by the above-described dropping operation.

  In order to solve this problem, it is possible to increase the compressed air pressure or the amount of compressed air to increase the internal pressure of the bag filter main body and to remove the dust on the dust collecting surface for regeneration. There is a concern that the tank and the compressor capacity for temporarily storing the compressed air become enormous, which causes an increase in equipment costs and causes cost problems, which are not easily adopted.

  And, as described above, the characteristics used for the bag filter medium include high dust collection efficiency, that is, less dust leakage, low pressure loss, that is, good air permeability and small pore diameter, In addition, the strength of the bag filter medium is large, for example, it does not break against the gas aeration pressure, has a long service life, for example, has high durability against repeated bending during pulse backwashing. Etc. were requested.

  For this reason, as a material of the filter medium for the bag filter, a felt obtained by mixing polyester, aramid, tetrafluoroethylene resin fiber and the like and needling is mainly used.

  However, bag filter media made of synthetic fiber felt have the disadvantages of having a large amount of dust leakage with respect to fine particles, low air permeability, and generally high pressure loss. There was a concern that the surface layer could not withstand dropping and cracks occurred and the dust leaked as it was.

  The object of the present invention is to improve the collection efficiency of dust in exhaust gas with low pressure loss and to have a large dust collection capacity, which can withstand the dust removal operation, that is, the expansion / contraction operation of the filter medium, and has a long service life. It is intended to provide a long bag filter media.

  An object of the present invention is to provide a bag filter medium that is low in pressure loss, excellent in dust collection efficiency and strength, and easy to remove dust during backwashing.

  An object of the present invention is to extend the cleaning and regeneration period of the dust collecting surface and reduce maintenance costs such as running costs.

An object of the present invention is to provide a novel bag filter medium that can be incinerated while having dust collection efficiency and low pressure loss.

  An object of the present invention is to provide a bag filter medium excellent in long-term heat resistance and chemical resistance.

  The first solving means of the present invention is to laminate a bag filter filter medium on a nonwoven fabric or woven fabric made of synthetic fiber, glass fiber, natural fiber or the like, and laminate a superfine fiber layer having a fiber diameter of 0.01 to 0.5 μm, It is composed of a laminated filter medium in which a nonwoven fabric or a woven fabric and an ultrafine fiber are integrated.

  According to a second solution of the present invention, a bag filter filter medium is formed by attaching an adhesive medium of a binder, molten fiber or adhesive powder to the surface or back surface of a thin layer of super fine fibers of the laminated filter medium, and the fiber diameter is 1 to 100 μm. And a multilayer laminated filter medium in which a non-woven fabric or woven fabric having a thickness of 0.05 to 2.5 mm is dried and fixed and integrated.

  According to a third solution of the present invention, the bag filter medium is entangled with a non-woven fabric or woven fabric made of synthetic fiber, glass fiber, natural fiber, or the like, with ultrafine fibers having a fiber diameter of 0.01 to 0.5 μm, It is composed of a mixed filter medium in which a nonwoven fabric or a woven fabric and superfine fibers are mixed and integrated.

  According to a fourth solution of the present invention, a bag filter medium is attached to the front or back surface of a mixed filter medium with a binder, molten fiber or adhesive powder adhesive medium, and the fiber diameter is 1 to 100 μm and the thickness is 0.05 to 2. It is composed of a mixed filter medium in which a non-woven fabric or woven fabric of .5 mm is dry-fixed and integrated.

  According to a fifth solution of the present invention, an ion exchange group or a chemically reactive group is imparted to the filter medium of the above [0014] to [0017] by means of graft polymerization, chemical solution deposition method or activated carbon deposition method. It is composed of a gas removal filter medium.

  According to a sixth solving means of the present invention, the bag filter medium is a cylindrical filter medium in which the filter medium or the gas removal filter medium is formed in a cylindrical shape.

  According to a seventh solution of the present invention, the bag filter filter medium is formed into a circular shape or an envelope shape by folding the filter filter medium or the gas removal filter medium in a zigzag shape and then folding it.

  Here, the nonwoven fabric or woven fabric that is the base material of the filter medium can be organic fibers such as polyester fibers, polyamide fibers, polyethylene fibers, rayon, polypropylene fibers, glass fibers, and pulp fibers. These may be used alone or in combination of two or more.

  As a method for forming these nonwoven fabrics or woven fabrics, a method using a wet papermaking method, a dry method, a spunbond method, a melt blow method, an electrospinning method, or the like is used.

  A binder, molten fiber, adhesive powder, or the like is used as an adhesive medium for the filter medium. As the binder, an organic binder, an inorganic binder, or a mixed binder obtained by mixing is used. An acrylic resin is preferably used. As the molten fiber, a fiber having a core-sheath structure is used. Further, resin powder having a low softening point is used as the adhesive powder.

  The ultrafine fiber layer is formed of ultrafine fibers made of polymer fibers having an average fiber diameter of 0.001 to 1 μm spun by an electrospinning method. Thus, the super extra fine fiber layer manufactured by the electrospinning method has sufficient strength when used in combination with other base materials such as other nonwoven fabrics and woven fabrics, and therefore has excellent workability of the bag filter medium. The electrospinning method is a conventionally known method, and is a method of drawing and fiberizing by applying an electric field to a spinning solution supplied from a nozzle or the like.

  The ultra-fine fiber of the filter medium refers to one having a single fiber diameter in the range of 0.01 to 0.5 μm, and the form may be a fibrous form, and does not stick to the length or cross-sectional shape. Is. The material constituting the ultrafine fiber is not particularly limited, and examples thereof include polyester, polyamide, polyolefin, polyphenylene sulfide (PPS), and aramid. Examples of the polyester include polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), and polylactic acid (PLA). Examples of polyamide include nylon 6 (N6), nylon 66 (N66), nylon 11 (N11), and the like. Examples of the polyolefin include polyethylene (PE), polypropylene (PP), and polystyrene (PS). In addition to the above materials, it is of course possible to use phenol resins, polyacrylonitrile (PAN), polyvinyl alcohol (PVA), polyethersulfone (PES), polysulfone, fluorine-based polymers and their derivatives.

  The super extra fine fiber layer used in the present invention is composed of the super extra fine fibers as described above, but the super extra fine fibers are preferably not in a bundle but in a state in which the extra extra fine fibers are dispersed. This is because the ultrafine fiber has a slip flow effect that improves the fluid flow and lowers the pressure loss.

  Subsequently, the ultrafine fibers layered can be formed by laminating the fiberized ultrafine fibers on a nonwoven fabric or a woven fabric. The shape of the nonwoven fabric or woven fabric is not particularly limited as long as it can collect ultrafine fibers and can maintain the workability and strength of the bag filter medium.

  The production of a multilayer laminated filter medium or a mixed filter medium that exhibits a high-efficiency dust collection function with low pressure loss is a synthetic fiber having a fiber diameter of 1.0 to 100 μm and a thickness of 0.1 to 1.0 mm. A super-fine fiber stretched by attaching an adhesive medium of binder, molten fiber or adhesive powder to a nonwoven fabric or woven fabric made of glass fiber, natural fiber, etc., and then applying an electric field to the spinning material supplied from a nozzle etc. A filter medium in which the nonwoven fabric or woven fabric and the ultrafine fiber are integrated is formed by laminating or mixing the ultrafine fiber layers of 0.01 to 0.5 μm by electrospinning method or melt spinning method. To do.

  Furthermore, another form of the filter medium is that the fiber diameter is 1 to 100 μm and the thickness is 0.05 to 0.05 by attaching an adhesive medium of a binder, molten fiber or adhesive powder to the surface or back surface of the ultrafine fiber layer of the filter medium. It is a multilayer laminated filter medium in which a 2.5 mm non-woven fabric or woven fabric is dried and fixed, or is simply physically stacked and integrated.

  The production of a bag filter medium that exhibits a high-efficiency dust collecting function with low pressure loss is obtained by winding the filter medium in a cylindrical shape and integrating the ends into a cylindrical filter medium.

  Another bag filter medium is manufactured by folding the filter medium in a zigzag shape and folding it into a circular or envelope shape.

  Next, the production of a gas removal filter medium having an ion exchange group and a reactive group that has a low-pressure-loss and high-efficiency dust collection function and exhibits a pollutant gas adsorption function is the multilayer laminated filter medium. Alternatively, the mixed filter medium is irradiated with radiation such as α rays, β rays, γ rays, X rays, and electron beams to generate radicals (reaction initiation species). The laminated filter medium after irradiation is immersed in a polymerizable monomer-containing solution, and the polymerizable monomer is graft-polymerized on the multilayer laminated filter medium or mixed filter medium fiber. As a result, the polymerizable monomer is bound to the fiber as a graft polymerization side chain. The resulting fiber having a polymerizable monomer as a side chain is contact-reacted with a compound having an anion exchange group or a cation exchange group, whereby an ion exchange group is introduced into the polymerizable monomer of the graft polymerized side chain, and finally A product is obtained. Further, a gas removal filter medium can be produced by impregnating and drying a chemical reaction solution having reactivity with gas. Therefore, when such a product comes into contact with a pollutant gas such as an alkaline gas or acid gas in the air, the ultrafine fiber having a large surface area comes into contact with the gas and efficiently comes into contact with the low pressure loss. The removal rate is excellent.

  Examples of the polymerizable monomer include vinyl sulfonic acid, styrene sulfonic acid, vinyl pyridine acrylic acid, methacrylic acid, arylamine, and chloromethyl sulfonic acid, which are appropriately selected depending on the necessity of a cation exchange group and an anion exchange group. And are not limited to these ranges.

  As the impregnation reaction solution, potassium hydroxide, potassium carbonate, sulfuric acid, amine or the like is used.

  The gas removal filter medium is made by laminating a superfine fiber layer having a fiber diameter of 0.01 to 0.5 μm or mixing a superfine fiber on a nonwoven fabric or a woven fabric to which an ion exchange group or a chemical is added, and the nonwoven fabric or the woven fabric. The structure which combined cloth and super extra fine fiber may be sufficient.

  And the production of bag filter media that has a high efficiency dust collection function and exhibits a pollutant gas adsorption function with low pressure loss, is to wrap the gas removal filter media in a cylindrical shape or fold it into a zigzag shape. It is made into a cylindrical filter medium in a circular shape by fold folding.

  The effect | action by the said problem solution is as follows.

First, air containing pollutant gas and dust sucked into the bag filter by the operation of the dust collector is exhausted out of the bag filter through the bag filter medium. At this time, the dust is collected by the ultrafine fiber layer in which ultrafine holes are formed. Here, since it is comprised from the super extra fine fiber layer provided with the precise | minute high density capture | acquisition function which consists of a super extra fine fiber, a highly efficient function is exhibited though it is a low pressure loss.
Also, when removing dust from bag filter media, the electrospinning method is used, and by using an ultrafine fiber layer (nonwoven fabric layer) and a reinforcing base material, a shape retention function and a dust retention capacity for the purpose of improving strength are achieved. Since a large function can be formed, it is possible to provide a bag filter medium that can withstand the dust removal operation of the bag filter medium, that is, the expansion / contraction operation of the filter medium, and has a long service life as a result.

As described above, the bag filter medium of the present invention has the following effects.
(1) The bag filter medium is a mixture of a super-fine fiber layer having a shape retention function for the purpose of improving strength and a dense non-woven fabric or woven cloth having a large dust retention capacity and a dense high-density capture function composed of ultra-fine fibers. Since the dust is collected by the superfine fiber layer, it can be reliably collected even for a wide range of dust containing fine particles, and a highly efficient function can be exhibited with a low pressure loss.
(2) The bag filter media is reinforced with a non-woven fabric or woven fabric with a shape retention function and a large dust holding capacity for the purpose of improving strength, so that it can withstand repeated backwash operations and extend the life of the bag filter media. It is possible to minimize the deterioration of the collection function.
(3) Since the filter media used for the regeneration is a bag filter media for regeneration by removing from the gas removal filter media provided with ion exchange groups or reactive groups by techniques such as graft polymerization or chemical solution impregnation, the polluted gas is reliably removed. At the same time, it is possible to exhibit a highly efficient function with a low pressure loss.
(4) Since the surface of the bag filter medium can be made smooth, the separation of dust can be improved, and even if the amount of backwash air generated during regeneration is small, it can be separated and regenerated from the ultrafine fiber layer, so compressed air The capacity of the buffer tank for storing water can be minimized and power can be saved.
(5) By stacking or mixing and integrating the ultrafine transition layer, dust collection efficiency is greatly improved, and peeling efficiency is also greatly improved.
That is, it is possible to make compatible functions compatible with each other.
(6) The bag filter medium of the present invention is a non-woven fabric in which the intersections of ultrafine fibers are heat-sealed or entangled with a high-strength fiber net that is heat-sealed or entangled. Therefore, this filter medium has excellent tensile strength, small pressure loss, can capture fine particles of 5 μm or less, excellent filtration accuracy, high air permeability, good pore diameter stability against heating, and does not open by heating etc. . Since this filter medium has good pore diameter stability against heating, stable high-accuracy filtration can be performed even if heating, high-temperature filtration, or the like is performed. Moreover, this filter medium can process a fold fold uneven | corrugated shape. In addition to the above effect, the fold-folded filter medium has an effect that the filtration life is long because of the large filtration area.

Bag filter media with cylindrical filter media. The top view of FIG. Bag filter media made by fold-folding laminated filter media into a zigzag shape into a cylindrical shape. FIG. 4 is a plan view of FIG. 3.

  FIG. 1 shows a bag filter medium 1. The bag filter medium 1 is formed by winding a filter medium 2 in a cylindrical shape and integrating the ends into a cylindrical filter medium.

FIG. 3 shows a filter medium 2 which is folded into a zigzag shape and is folded into a circular shape, and ends thereof are integrated into a cylindrical filter medium.
The multilayer filter medium 2 has the following configuration.

  The first embodiment of the filter medium 2 is the surface of the filter base 3 made of a nonwoven fabric or a woven fabric made of glass fiber, synthetic fiber or natural fiber having a fiber diameter of 1.0 to 100 μm and a thickness of 0.1 to 1.0 mm. A thin layer 4 of ultra-fine fibers having a fiber diameter of 0.01 to 0.5 μm is laminated and fixed by drying and adhering to each other.

  In the second embodiment, the filter medium 2 is formed by integrating a nonwoven fabric or a woven fabric having a fiber diameter of 1 to 100 μm and a thickness of 0.05 to 2.5 mm on the surface of the thin layer 4 of ultrafine fibers of the above embodiment. Is done.

In the third embodiment, the fiber diameter is 1.0 to 100 μm and the fiber diameter on the surface of the filter substrate 3 of a nonwoven fabric or a woven fabric made of glass fiber, synthetic fiber, natural fiber or the like having a thickness of 0.1 to 1.0 mm. Of ultrafine fibers having a diameter of 0.01 to 0.5 μm are overlapped and needling processed to mix the fibers, or a binder, a molten fiber or an adhesive powder adhesive medium is attached to the surface of the filter base 3, and the fiber diameter is added thereto. Is formed by superimposing ultrafine fibers having a diameter of 0.01 to 0.5 μm and performing needling processing and mixing the fibers to form an integrated filter medium 2.

  In the fourth embodiment, the surface of a nonwoven fabric or woven fabric made of glass fiber, synthetic fiber or natural fiber having a fiber diameter of 1.0 to 100 μm and a thickness of 0.1 to 1.0 mm is bonded to a binder, molten fiber, or adhesive powder. After attaching a thin layer of ultrafine fibers having a fiber diameter of 0.01 to 0.5 μm thereon and drying and fixing them to irradiate the filter substrate 3 with radiation, styrene sulfonic acid or A polymerizable monomer monomer of glycidyl acrylate is contacted to form a cation exchange group or an anion exchange group, respectively. Thereby, the gas removal filter medium 2 having a cation exchange group, that is, an alkali gas adsorption function or an anion exchange group, that is, an acid gas adsorption function is formed.

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage, and a plurality of components disclosed in the embodiments. Various modifications can be made by an appropriate combination of the above.

  Furthermore, it can be used for an air filter as a static collection without using a dropping mechanism.

  In the industry dealing with bag filters, bag filter media having low pressure loss, high collection efficiency and long life performance have been sought after. However, these performances have contradictory performances, making it difficult to create an ideal one. Therefore, the development of bag filter media having ideal performance in the filter industry has been attracting attention as a result of technological development in the textile industry in recent years and the development of ultra-fine fibers. Therefore, the present invention is intended to solve these problems and to provide a bag filter medium that exhibits the ultra-fine fiber effect without regret, has high efficiency with low pressure loss, and has a multi-layered, smooth surface and long life. The invention is extremely useful in industry.

DESCRIPTION OF SYMBOLS 1 ... Bag filter filter medium 2 ... Filter filter medium 3 ... Filter base material 4 ... Thin layer of super fine fiber

Claims (7)

  Laminate made of synthetic fiber, glass fiber, natural fiber, etc., laminated with a superfine fiber layer having a fiber diameter of 0.01 to 0.5 μm, and the nonwoven fabric or woven cloth and superfine fiber are integrated. A bag filter medium for scraping regeneration, wherein the filter medium is wound in a cylindrical shape, and ends are joined to form a cylindrical filter medium.   An adhesive medium of a binder, molten fiber or adhesive powder is attached to the surface or back surface of the thin layer of the ultrafine fiber of the multilayer filter medium of claim 1, the fiber diameter is 1 to 100 μm, and the thickness is 0.05 to 2.5 mm A bag filter medium characterized in that a multilayer laminated filter medium in which a nonwoven fabric or a woven cloth is dry-fixed and integrated to form a cylindrical filter medium.   A non-woven fabric or woven fabric made of synthetic fiber, glass fiber, natural fiber or the like is entangled with a super fine fiber layer having a fiber diameter of 0.01 to 0.5 μm, and the non-woven fabric or woven fabric and the super fine fiber are mixed and integrated. A bag filter medium for scraping regeneration, wherein the mixed filter medium is wound in a cylindrical shape, and ends are joined to form a cylindrical filter medium.   A binder, molten fiber or adhesive powder adhesive medium is attached to the front or back surface of the mixed filter medium of claim 3, and a non-woven fabric or woven fabric having a fiber diameter of 1 to 100 μm and a thickness of 0.05 to 2.5 mm is fixed by drying. A bag filter medium characterized in that a mixed filter medium integrated into a cylindrical shape is wound into a cylindrical filter medium.   A bag filter medium, wherein the laminated filter medium of claims 1 and 2 is folded into a zigzag shape and fold-folded into a circular shape or an envelope shape.   A bag filter medium, wherein the mixed filter medium of claims 3 and 4 is folded into a zigzag shape and fold-folded into a circular shape or an envelope shape.   A gas removal filter medium to which an ion exchange group or a chemical reaction group is added is wrapped around the filter medium according to any one of claims 1 to 4 by a graft polymerization method, a chemical solution deposition method, or an activated carbon deposition method, or is folded in a zigzag shape. A bag filter medium characterized by being folded and folded into a circular shape or an envelope shape.

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