JP2008086865A - Filter and filter manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter in which a granulous or powdery adsorbent is combined and held by a binder comprising fibers, and which has no problems that a manufacturing method such as a compression molding or a sheet making makes a plate-like or sheet-like filter of a high density, by which it is impossible to decrease or control the density, for example, the passage of oil through the filter requires time. <P>SOLUTION: The filter has a constitution that its main body comprises the granulous or powdery adsorbent and the fibers as a binder combining and holding the adsorbents. The filter comprises a plurality of granulation filters in which the fibers combining and holding the adsorbents are granulously entangled. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a filter for purifying liquids and gases containing pollutants such as used cooking oil and air containing odors, and a method for producing the same.

  In order to purify liquids and gases containing pollutants such as used cooking oil and air containing odors, filters equipped with an adsorbent such as activated carbon are used. The adsorbent is disposed in a flow path of a liquid or gas (simply referred to as a purification target) containing the contaminants to be purified and adsorbs and filters the contaminant contained in the purification target. A case filled with a powdery adsorbent is disposed (for example, see Patent Document 1), or a granular or powdery adsorbent bonded with a binder is disposed (for example, Patent Document 2, Patent Document 3). When filling granular or powdery adsorbents without binding with a binder, those using powdered activated carbon have a large surface area and high contact with the object to be purified because they are powdered, but liquid When the target to be purified is flowed, it becomes difficult to penetrate as it is mud (that is, the pressure loss is high), and in the case of using granular activated carbon, there is a large space between the grains compared to the case of powder, so the penetration rate is Although it is fast (that is, the pressure loss is low), it is granular, so its surface area is small compared to powdered activated carbon, and its contactability is low. To increase the contactability, the amount must be increased.

  Adhesives that adhere the adsorbents are often used as binders for binding granular and powdery adsorbents. On the other hand, fibers such as pulp are used as binders to eliminate the need for adhesives. The thing is shown by the said patent document 2 and patent document 3.

  In Patent Document 2, a piece of paper such as newspaper or copy paper is defibrated in water, mixed with granular carbides such as rice husk charcoal or charcoal, and then flows into a mold to form a plate. The filter to be shown is shown.

  Patent Document 3 discloses a product obtained by mixing activated carbon into disaggregated pulp and molding it.

  Further, Patent Document 4 discloses a method in which inorganic fine particles having photocatalytic activity instead of an adsorbent are bonded with a binder. This is because the inorganic fine particles having photocatalytic activity, paper fibers and pulp, and water are put into a granulator and mixed, whereby a slurry of the photocatalytic pulp composition composed of the inorganic fine particles, pulp and water is prepared. It is produced and paper is made to produce a photocatalyst-containing sheet.

  As described above, these Patent Documents 2 to 4 use a fiber such as pulp as a binder to bind and hold granular or powdery particles, and compress them with a mold or make paper. Thus, the filter is formed into a plate shape or a sheet shape.

By the way, since the filter formed in plate shape or sheet shape is manufactured by a manufacturing method such as compression molding or papermaking, it is difficult to reduce its density (adsorbent and fiber density). It is also difficult to change to a high state. For this reason, it is difficult to adjust the resistance and pressure loss when the fluid to be purified passes through the filter. For example, it takes time for used oil to pass through the filter. It was.
JP-A-8-10539 JP 2002-219314 A JP 2001-212413 A JP 2002-61098 A

  The present invention has been made in view of the above points, and an object of the present invention is a filter that holds a particulate or powdery adsorbent bound by a binder made of fibers, and is formed by compression molding or Forming a plate or sheet by a manufacturing method such as papermaking will result in a high density state, and the density cannot be reduced or adjusted, for example, it takes time for oil to pass through the filter. This is to provide a filter that does not.

  In order to solve the above problems, a filter according to claim 1 is a filter mainly composed of a particulate or powdery adsorbent and a fiber as a binder that binds and holds the adsorbent. The adsorbent is bonded to and held by a plurality of granulated filters in which the fibers are entangled in the form of particles.

  There are gaps between the entangled fibers and the fibers have elasticity, and the plurality of granulation filters in which the fibers are entangled in the form of particles are the volume occupied by the granulation filter and the volume of the space between the granulation filters Is larger or smaller and various, especially if it is collected without compression, the density is lower than the sheet-like filter, but when compressed, the volume occupied by the granulation filter due to deformation of the fiber, and The volume of the space between the granulating filters changes and decreases, and the density increases. Thereby, the density of the filter can be adjusted.

  Moreover, in the invention which concerns on Claim 2, while forming the fiber as a binder by 1 or more types of pulp or / and a chemical fiber in the filter which concerns on Claim 1, activated carbon and other adsorption agent 1 are used as adsorption agent. It is characterized by being formed of more than one type.

  By setting it as such a structure, a filter can be formed with various materials including common materials, such as a pulp and activated carbon.

  Moreover, in the invention which concerns on Claim 3, in the filter which concerns on Claim 1 or 2, the particle size of the granulation filter which the fiber which couple | bonded and hold | maintained the adsorbent was entangled is 0.3- It is characterized by being 20 mm.

  By adopting such a configuration, when the particle size of the granulation filter exceeds 10 mm, it is easy to pass through the gaps between the granulation filters when the purification target such as oil is flowed. It is possible to prevent the adsorption of contaminants and the efficiency of filtration from being reduced.

  The invention according to claim 4 is characterized in that, in the filter according to any one of claims 1 to 3, a plurality of granulated filters are accommodated in a filter case made of fibers. is there.

  By adopting such a configuration, handling of the granulation filter becomes easy, and an effect of filtration by a filter case made of fibers can be expected.

  Further, the filter manufacturing method according to claim 5 includes stirring and mixing means for mixing a mixture of a particulate or powdered adsorbent, a fiber as a binder for binding and holding the adsorbent, and water. The mixture is stirred and mixed by stirring and mixing means in the stirring and mixing container, and the water in the mixture is evaporated simultaneously or while stirring and mixing, and then the adsorbent is evaporated. A plurality of granulation filters formed by entangled fibers held together are formed in a particulate form.

  By adopting such a configuration, it is possible to produce a granulation filter that easily filters using a general-purpose machine such as a stirrer or a granulator equipped with a stirring and mixing means and a stirring and mixing container. Become.

  Further, in the invention according to claim 6, in the filter manufacturing method according to claim 5, magnesium oxide, calcium oxide, magnesium carbonate, calcium carbonate as a deoxidizer in addition to the adsorbent, fiber, and water in the mixture In addition, one or more of calcium silicate, magnesium silicate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, caustic soda, and soda ash are mixed.

  With such a configuration, it is possible to provide the filter with a function of regenerating the oil oxidized by the deoxidizer.

  In the present invention, the filter is composed of a granulated filter in which fibers holding the adsorbent are entangled in a particulate form, so that the density of the filter can be adjusted from low to high. It takes no time for the filter to pass through the filter, and the pressure loss and the filter passing time can be adjusted.

  In addition, in the case of a powdered adsorbent supported by fibers to form a granular granulation filter, the high contactability that is an advantage of the powder adsorbent and the penetration rate that is an advantage of the granular adsorbent. It becomes possible to have both speed.

  Moreover, it becomes possible to manufacture a granulation filter that easily filters using a general machine equipped with a stirring and mixing means and a stirring and mixing container, for example, a machine such as a stirrer and a granulator.

  The present invention will be described based on an embodiment. The filter according to the present invention is mainly composed of a particulate or powdery adsorbent and fibers as a binder that binds and holds the adsorbent.

  Examples of the adsorbent include zeolite, amorphous silica, bentonite, activated alumina, activated clay and the like, and these can be used alone or in combination of two or more according to the intended use. The preferred adsorbent for oil decolorization is activated carbon.

  As the activated carbon, in addition to bamboo activated carbon, for example, other plant activated carbon (for example, activated carbon made from coconut shell, wood flour, raw ash, etc.), mineral activated carbon (for example, peat charcoal, leki charcoal, pitch, coke, etc.) Activated carbon used as a raw material), resin-based activated carbon (for example, activated carbon using phenol resin, acrylic resin, etc. as a raw material), and the like. These can be used alone or in combination of two or more.

The specific surface area of the adsorbent is about 300 to 3000 m ² / g (preferably 700 to 2500 m ² / g), and the average pore diameter is 1 to 100 mm (preferably 5 to 20 mm) depending on the contaminant to be adsorbed. To the extent. Note that 1Å = 0.1 nm.

  This adsorbent is in the form of particles or powder, and the average particle size is about 5 to 500 μm (preferably 30 to 40 μm). When the average particle size deviates from the above range, the uniform dispersibility of the adsorbent is reduced and the adsorption efficiency is lowered. When the average particle size is within the above range, the fiber as a binder described below is uniformly entangled and held, and the adsorption efficiency. Is expensive.

  Examples of the fibers include pulp, various natural fibers, and chemical fibers. Examples of natural fibers include animal fibers such as wool and silk, plant cellulose fibers such as cotton, hemp, and coconut fiber, and mineral fibers such as rock wool. Chemical fibers include recycled fibers such as viscose artificial silk (for example, rayon), semi-synthetic fibers such as acetate artificial silk, polyamide fibers such as 6-nylon, polyester fibers, acrylic fibers, polyvinyl alcohol fibers such as vinylon, etc. Is mentioned. Furthermore, inorganic fibers such as metal fibers and carbon fibers may be used, and these fibers can be used alone or in combination of two or more.

  Examples of the pulp include wood pulp, linter pulp, straw pulp, mulberry, sanjo, and the like, and these pulps can be used alone or in combination of two or more. Furthermore, when pulp and chemical fiber are combined, filter strength and moldability can be improved, and the blending ratio (weight ratio) thereof is, for example, pulp: chemical fiber = 100: 0-50: 50 (preferably 100: 0). 70:30).

  The average diameter of the fibers is about 0.1 to 20 μm (preferably 1 to 10 μm), and the average length is about 100 μm to 30 mm (preferably 500 μm to 10 mm).

  The filter in which the adsorbent is entangled with the fiber is conventionally formed into a plate shape or a sheet shape by a manufacturing method such as compression molding or papermaking. On the other hand, in the present invention, the adsorbent is bound and held. A plurality of granulation filters in which fibers are entangled in a granular form (that is, a filter for a granulated product by a stirrer or a granulator to be described later, and a granular filter piece) are formed at an appropriate density. This is a filter that is gathered together in the manner described below.

  A large number of granulation filters forming a filter can be produced by a machine (hereinafter referred to as a production apparatus) equipped with a stirring and mixing means and a stirring and mixing container, such as a stirrer and a granulator.

  Although not shown in the drawings, the manufacturing apparatus includes a stirring and mixing container for containing a mixture to be stirred and mixed therein, and a stirring and mixing unit for stirring and mixing the mixture in the stirring and mixing container. The stirring and mixing container is provided with an inlet and an outlet that can be opened and closed by an open / close lid, and the inside and the outside communicate with each other through the inlet and the outlet.

  The stirring and mixing means stirs and mixes the mixture in the stirring and mixing container. A stirring shaft provided with a stirring blade and made rotatable is disposed in the stirring and mixing container, and the stirring shaft is driven by a driving means such as a motor. It is driven to rotate. The form of the agitation shaft and the agitation blade is not particularly limited. For example, the agitation shaft is pivotally supported on a position facing the inner wall of the agitation mixing vessel, or is cantilevered toward the inside of the agitation mixing vessel. The stirring blade may be any one that can stir and mix the internal mixture as the stirring shaft rotates. Further, as in the case of a granulator such as a so-called mixer, mixing may be promoted by rotating a mixing tank (that is, a stirring and mixing container).

  Further, the manufacturing apparatus includes a discharge unit that enables discharge of air containing moisture in the stirring and mixing container. In addition, when no aeration means is provided, if the charging port is formed at a position higher than the mixture in the stirring and mixing vessel, air containing moisture in the stirring and mixing vessel is discharged through the charging port. It may be.

  This manufacturing apparatus may be a machine provided with a stirring and mixing means and a stirring and mixing container as described above, and for example, a general machine such as a garbage disposal machine or a granulator can be used.

  Next, the manufacturing method which manufactures a filter (granulation filter) using this manufacturing apparatus is demonstrated.

  A mixture obtained by mixing particulate or powdered adsorbent, fibers, and water is put into a stirring and mixing container. When they are put in, they may be put in separately, as long as they are mixed when housed inside. The blending ratio of the fiber and the adsorbent will be described later depending on the type of the fiber and the adsorbent, but when using pulp for the fiber and activated carbon for the adsorbent, pulp: activated carbon = 9: 1 to 1: 2, preferably 4 : 1 to 2: 1. Further, water is only used as a medium for mixing, and hardly remains in the finished granulation filter. Therefore, it is not necessary to adjust the blending ratio if an amount of water that is sufficiently stirred and mixed is mixed.

  In addition, when a filter is used for filtration of used cooking oil, magnesium oxide, calcium oxide (baked shellfish), magnesium carbonate, calcium carbonate, calcium silicate, magnesium silicate, water are further added to the above mixture as a deoxidizer. It is preferable to add and mix one or more of calcium oxide, magnesium hydroxide, aluminum hydroxide, caustic soda and soda ash. Thereby, the regeneration function of the oil oxidized by the deoxidizer can be imparted to the filter. In addition, other additives may be appropriately added according to other purposes.

  Next, the mixture is stirred and mixed by the stirring and mixing means. As a result, the fibers are stirred and mixed in the mixture, sufficiently defibrated and entangled, and the particulate or powder adsorbent is also sufficiently mixed. Then, after stirring or mixing at the same time or after stirring and mixing, the air containing moisture in the stirring and mixing container is discharged by the discharging means to reduce the moisture in the mixture. At this time, the stirring and mixing container may be provided with heating means such as a heater, and the mixture may be heated to promote evaporation of moisture in the mixture. Garbage treatment equipment is usually equipped with heating means for heating the stirring tank (stirring mixing container) to a temperature suitable for the work of degrading bacteria. The container can be heated.

  At the same time or after stirring and mixing while stirring and mixing, the water in the mixture is evaporated to dehydrate the mixture, so that the particulate or powdered adsorbent adheres and the adsorbent is bound and held by the fibers. It becomes a state. In the present invention, at this time, the fibers held by binding the adsorbent as in the case of compression molding or papermaking do not become plate-like or sheet-like. That is, since the mixture is dehydrated while being stirred and mixed, a large number of granulated filters are formed which are not formed as a whole like a plate or a sheet but are entangled in fine particles. The particle size of the granulation filter can be adjusted by the type and amount of the fiber, but is usually almost occupied by a granulation filter having a diameter of about 1 to 5 mm.

The granulation filter is used as a filter by concentrating a predetermined number within a predetermined volume. The filter F in FIG. 1 (a), shows a granulated filter _{F 0} in FIG. 1 (b). In the filter F in which the granulated filters F ₀ of the present invention are densely packed, a space is interposed between the granulated filters F ₀ , and compared with a conventional plate-like or sheet-like filter, The density, that is, the density of adsorbent and fibers (and possibly magnesium oxide) relative to the volume occupied by the dense granulation filter F ₀ shell, is low. However, this is the state taken out from the stirring and mixing container, and if compressed, a higher density can be obtained.

In the present embodiment, granulation filter F ₀ is accommodated in the filter case composed of pulp fibers. As shown in FIG. 2, the filter case 1 has a case body 2 in which a flange 21 is formed on a bottomed cylinder 20 that opens upward, and a substantially plate shape (substantially sheet shape) that closes the upper opening of the case body 2. It consists of a case lid 3. The outer shape of the case lid 3 is formed substantially the same as the outer shape of the flange 21 of the case body 2. The case lid 3 is bonded to the case main body 2 in such a state that the case main body 2 is filled with the granulation filter F ₀ , the case lid 3 is overlapped on the flange 21, and the overlapped portion is bonded by the adhesive 4. As the adhesive 4, starch, corn starch or the like used as a food additive is used, and there is no problem even if the edible oil adsorbed and filtered by the filter F is reused.

  As in the present embodiment, by bonding the case lid 3 to the case main body 2 with the adhesive 4, the case lid 3 can be manufactured by a dry method of manufacturing while maintaining a dry state, and the productivity is improved. That is, conventionally, in order to join members made of pulp fibers, a wet method is used in which both members are joined by entangled defibrated pulp without using an adhesive. In this case, a large amount of water is used to disperse the defibrated pulp, and the bonding member is soaked with moisture, so that the drying process for drying the moisture takes a lot of time and the productivity is poor. By using this, only the adhesive needs to be dried, so that the drying process is greatly shortened and the productivity is improved.

  In the present invention, the filter is composed of a plurality of granulation filters in which fibers held by adsorbents are held together in a particulate form, so that there is a conventional space between the granulation filters. Although the density is lower than that of the plate-like or sheet-like filter, higher density can be achieved by compression. This makes it possible to adjust the density of the filter. For example, when the density of a conventional plate-like or sheet-like filter is high and the time required to pass through the filter is long, the plate-like or sheet-like filter is used. If a filter filled with a plurality of granulation filters of the present invention at a low density is used instead, the resistance is reduced and the time required to pass is shortened.

  In this way, the resistance and pressure loss can be adjusted by setting the density of the filter (the packing density of the granulation filter) as desired, and the thickness of the filter can be changed by keeping the packing density of the granulation filter constant. But resistance and pressure loss can be adjusted.

  In addition, in the case of a filter formed in a conventional plate shape or sheet shape, if the density is high and the resistance when passing through the filter is large, the filter and the filter are not passed through the filter when flowing through the purification target. There is a problem that the amount passing through the gap between the inner wall of the filter container to be accommodated increases and the adsorption and filtration performance is not exhibited as designed, but in the present invention, the granulation filter and the inner wall of the filter container Since the gap between the two is substantially the same as the gap between the granulating filters, such a problem does not occur.

  In addition, when activated carbon is used as the adsorbent, deodorizing and decoloring effects can be obtained by adsorption of contaminants in the purification target, and by using fibers as the adsorbent binder, impurities that are not adsorbed by the adsorbent can be filtered. Can do.

  In the production method of the present invention, if it is produced by a production apparatus equipped with a stirring and mixing means and a stirring and mixing container, for example, using a general-purpose machine such as a garbage disposal machine or a granulator, It becomes possible to manufacture a granulated filter that easily filters. In addition, by manufacturing a filter in which a granulation filter is filled in a filter case by a dry method, a manufacturing process is improved without a drying step as compared with a wet method.

  As a filter, for example, a filter for 10 L filled with a granulating filter capable of purifying 10 L of oil is manufactured, and two filters are required to purify 20 L of oil, and 3 L of oil is purified. By performing the purification three times with one filter, it is possible to cope with one type of filter even if the amount of oil to be treated at one time is different.

  In addition, in the case of manufacturing by compression molding or papermaking as in the past, when the moisture of the adsorbent / fiber / water mixture (slurry) overflows from the mold or sucks, the oxidation contained in the moisture Additives such as magnesium and powdered adsorbents are lost with moisture and the yield is poor, but by dehydrating by evaporating the water in the mixture while stirring and mixing the mixture as in the present invention, Even if evaporates, additives such as magnesium oxide and powdery adsorbent are hardly lost, and the yield is greatly improved. At this time, the amount of water used can be significantly reduced (about 80 to 90%) as compared with the case of manufacturing by compression molding or papermaking.

As another embodiment, FIG. 3 shows a filter F for air conditioning. As shown in FIG. 3 (a), the inlet, is filled with a granulated filter F ₀ to outlet the formed casing 5a constitutes a main body of the filter F, the filter inlet of the casing 5, the outlet In order to prevent the powdery or particulate adsorbent retained in F from leaking out, a finer leakage prevention filter 6 than the adsorbent is provided.

Further, as shown in FIG. 3 (b) is obtained by constituting the filter F by filling the granulated filter F ₀ in the pores of the honeycomb structure 7 in the casing 5b having a honeycomb structure 7. Even in this case, a leakage prevention filter (not shown) having a finer mesh than the adsorbent may be provided at the inlet and outlet of the casing 5b so that the adsorbent does not leak out.

  Thereby, even if it exists in the filter F for an air conditioning, the effect mentioned above can be acquired, and the filter F with high contact property with an adsorbent and quick penetration speed can be obtained.

Hereinafter, a test for evaluating the performance of the filter will be described.
<Comparison test 1>
A plurality of types of filters were manufactured by changing the mixing ratio of pulp as fibers and activated carbon as adsorbent, and performance tests were performed on each filter. The filter was set so that the granulated filter layer had a thickness of 30 mm, and air containing 400 ppm of ethyl acetate as the original odor was allowed to flow, and the residual ethyl acetate concentration (ppm) was measured to evaluate the deodorization efficiency (%). did. The mixing ratio of the filter and the evaluation results are shown in Table 1, and the graph is shown in FIG.

From the graphs in Table 1 and FIG. 4, there is no deodorizing ability when the activated carbon ratio (simply referred to as activated carbon ratio) to the total amount of pulp and activated carbon is 0, and when the activated carbon ratio is 0.166, the deodorizing efficiency is 80% and the activated carbon ratio is 0.2 It is found that the deodorizing efficiency exceeds 90% across the board and shows good adsorption power. In view of economy, a preferable range is an activated carbon ratio of 0.2 to 0.33.
<Comparison test 2>
Next, the deodorization efficiency was compared between the case of using the filter of the present invention and the case of using crushed activated carbon as a filter (comparative example). The filter in the present invention has a mixing ratio of pulp as fiber and activated carbon as adsorbent of 4: 1 (activated carbon ratio 0.2), and the amount of activated carbon in both filters is 10 g, 20 g, and 30 g. The same deodorization efficiency (%) of ethyl acetate as described above was evaluated. The amount of activated carbon of the filter and the evaluation results are shown in Table 2.

From Table 2, a difference of deodorization efficiency of 15%, 20g of 12.5%, and 20g of 7.5% is recognized when the amount of activated carbon is 10 g, and it is understood that the filter of the present invention is excellent. At the same weight, the particulate or powdered activated carbon having a smaller particle diameter than the crushed activated carbon has a larger adsorption area, and therefore exhibits high deodorization efficiency.
<Comparison test 3>
Next, adsorption was performed using the crushed activated carbon (comparative example) used in Comparative Test 2 and the filter of the present invention until the odor concentration reached equilibrium. The filter according to the present invention has a pulp / activated carbon blending ratio of 4: 1 (activated carbon ratio 0.2), as in Comparative Test 2, and a 10 L capacity odor bag so that the amount of activated carbon in both filters is 1 g. It was put in, filled with air containing 11400 ppm of ethyl acetate as an original odor, and the concentration when the remaining ethyl acetate concentration (ppm) was in an equilibrium state was measured and evaluated. Table 3 shows the mixing ratio of each filter and the evaluation results.

  From Table 3, it can be seen that the concentration of the filter of the present invention is low and the adsorbing power is excellent.

  In addition, the filter of the present invention is used for purifying various gases such as air conditioning, or for purifying various liquids such as water and oil, or for care products (bed mat adsorbent) and pet toilet aids. (Sorry adsorption, so-called “cat sand” such as urine absorption by pulp fiber), and various other uses are conceivable.

FIG. 1 shows an embodiment of the present invention, (a) showing a filter, and (b) showing a granulating filter constituting the filter. It is sectional drawing of the filter which accommodated the granulation filter in the filter case. (A) and (b) are perspective views showing other embodiments of the present invention, respectively. 6 is a graph showing the results of Comparative Test 1.

Explanation of symbols

F filter F ₀ granulation filter 1 filter case 2 case body 20 bottomed tube 21 flange 3 case lid 4 adhesive

Claims (6)

  A filter mainly composed of a particulate or powdered adsorbent and a fiber as a binder that binds and holds the adsorbent, and the fibers that bind and hold the adsorbent are in a particulate form A filter comprising a plurality of entangled granulation filters.   2. The filter according to claim 1, wherein the fiber as a binder is formed of one or more kinds of pulp and / or chemical fiber, and the adsorbent is formed of one or more kinds of activated carbon and other adsorbents.   The filter according to claim 1 or 2, wherein a particle size of a granulating filter in which fibers held by adsorbing an adsorbent are entangled in a particle shape is 0.3 to 20 mm.   The filter according to any one of claims 1 to 3, wherein a plurality of granulating filters are accommodated in a filter case made of fibers.   A mixture obtained by mixing particulate or powdered adsorbent, fibers as a binder for binding and holding the adsorbent, and water is put into a stirring and mixing vessel equipped with stirring and mixing means, and the stirring and mixing are performed. In the container, the mixture is stirred and mixed by stirring and mixing, and while stirring or mixing, or after stirring and mixing, the moisture of the mixture is evaporated to entangle the adsorbent-bound fibers in the form of particles. A method for producing a filter, comprising forming a plurality of granulated filters.   In addition to adsorbent, fiber, water, magnesium oxide, calcium oxide, magnesium carbonate, calcium carbonate, calcium silicate, magnesium silicate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, caustic soda, 6. The method for producing a filter according to claim 5, wherein at least one kind of soda ash is mixed.

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