JP2017221151A - Filter for filtrating impurities of liquid in brewing process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively filtrate impurities as a filter for filtrating impurities of a liquid in a brewing process without need for precoating.SOLUTION: There is provided a filter for filtrating impurities of a liquid in a brewing process, having a first layer fiber sheet arranged in an upstream side of a filtration flow path and a second layer fiber sheet arranged in a downstream side, the first layer fiber sheet has thickness of 75 μm or more and density of 0.3 to 0.65 g/cm, the second layer fiber sheet has thickness of 90 μm or more and density of 0.3 to 0.6 g/cm, and contains 60 mass% or more of lyocell with Canada standard freeness of 350 ml or less, and air infiltration resistance of a state that the first layer fiber sheet and the second layer fiber sheet are laminated is 30 sec. or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a liquid impurity filtration filter in a brewing process for collecting impurities from a liquid such as an alcoholic beverage or a liquid seasoning in the brewing process.

  Alcoholic beverages such as sake, wine, beer, shochu, whiskey, brandy, vodka and rum, and liquid seasonings such as soy sauce, mirin and vinegar are produced through brewing. In this brewing, various metabolites are obtained when fermenting raw materials such as grains and fruits, and in the brewing process, additives other than the raw materials may be used depending on the purpose, and unnecessary substances are filtered. There is a need.

  For example, sake, a brewed sake, is made from brown rice, which is a raw material, and steamed rice to make steamed rice. Sprinkle the rice seeds on the steamed rice to make a sake mother's rice cake, then add water, lactic acid, and koji into the tank. In addition, steamed rice and yeast can be added to grow the yeast and make a liquor.

  Continuously, adding rice, rice bran, and steamed rice to the tank containing the sake mother multiple times will create mash, and even more time will encourage mash fermentation. After mash fermentation, squeeze mash into liquor and sake lees. This process is called the upper tank.

  Due to this upper tank, moromi is roughly divided into liquid liquor and solid liquor. However, the sake contains impurities such as rice fragments, rice cake and yeast residue. In the tank, leave the liquor in the tank, and then pull it out. In addition, the liquor may be colored in a yellowish color, etc. In order to remove this coloration, activated carbon may be added to the tank containing the liquor after the upper tank to decolorize.

  The liquor that has been ori-drawn (referred to as the original liquor) has an ori precipitate in the original liquor tank, and is largely divided into a supernatant portion and a precipitate portion that includes ori. And at the time of filtration, filtration is started from the supernatant part first, and after the filtration of the finished part is finished, the precipitate part containing the olis is taken out and filtered.

  Specifically, as shown in FIG. 1 showing the overall configuration of the filtration system, an upper pipe 11 for extracting the supernatant portion of the raw liquor and a lower pipe 12 for extracting the sediment portion containing the olivine are connected from the raw liquor tank 10. These pipes join in the middle and are connected to the relay tank 13. The upper pipe 11 and the lower pipe 12 are each provided with a valve (not shown) and can be opened and closed individually.

  Further, a suction pipe 14 is connected to the relay tank 13, and the suction pipe 14 is connected to an inlet of the filtration device 16 via a pump 15 for pressure feeding. Inside the filtration device 16, dozens to dozens of filters 17 are set in parallel, and the suction pipe 14 is branched immediately before the filtration device 16 and connected to the upstream side of each filter 17 in the filtration device 16. ing.

  A discharge pipe 18 is connected to the outlet of the filtration device 16 on the downstream side of the filter 17, and a switching valve (not shown) is installed in the middle of the discharge pipe 18 so that the flow path from the filtration device 16 is directed in two directions. One flow path is connected to the relay tank 13, and the other flow path is connected to the recovery tank 19.

  At the time of filtration, as shown in FIG. 2, the flow path of the discharge pipe 18 is switched to the recovery tank 19, and the raw liquor tank 10—the upper pipe 11 or the lower pipe 12—the relay tank 13—the suction pipe 14—the filtration device 16 (filter 17)-Discharge pipe 18-Form a flow path for the recovery tank 19.

  At the start of filtration, first, the upper pipe 11 of the raw liquor tank 10 is opened, and the supernatant portion with less impurities of the raw liquor is taken out to the relay tank 13. Then, the supernatant portion accumulated in the relay tank 13 is sent to the inlet of the filtration device 16 through the suction pipe 14 and filtered by passing through the filter 17 of the filtration device 16. The filtered liquor is collected in the collection tank 19 through the discharge pipe 18 from the outlet of the filtration device 16. When the filtration of the supernatant portion of the raw liquor is completed, the upper pipe 11 is closed, the lower pipe 12 is opened, the precipitated portion is taken out from the raw liquor tank 10, and similarly filtered through the filter 17 of the filtration device 16. In these filtrations, the decolorized activated carbon contained in the raw liquor is simultaneously filtered and collected.

  The sake that has been filtered (the liquor collected in the collection tank) still contains yeast and enzymes, so the sake should be sterilized by sterilizing the yeast and denaturing proteins (enzymes). Mix. In addition, since the color and taste of sake may change depending on the preparation or modified protein, activated carbon is added again and aged in a storage tank (not shown).

  And after this ripening, the orientation is lowered and the filtration is performed. A new occurrence of orientation occurs when burning, blending and storing sake, but this orientation is fine, such as protein crystals, and does not settle even when left standing. An agglomerate (floc) combined with a lowering agent is formed and precipitated at the bottom of the tank. This process is called orientation reduction. Filtration is then performed to remove the floc. The same device as the filtration device 16 after the orientation pulling is used for the filtration after the orientation reduction.

  Here, the filter 17 used in the conventional filtration device after the orientation is lowered, the required number (ten to several tens) of the filtration device 16 is obtained each time immediately before the liquor is filtered. The filter device 16 was used.

  That is, in order to produce the filter 17 used in the filtering device 16, a necessary number of filter original plates 17a in which a coarse filter paper or a filter cloth is attached to a support plate such as a metal mesh material as a reinforcing material is prepared. Each is set in the filtration device 16. Since the filter base plate 17a is rough and cannot be collected effectively if it is left as it is, the filter 17 collects the side by accumulating fine filter aids on the surface of the filter base plate 17a to form a precoat layer. Can do.

The method for forming the precoat layer on the filter base plate 17a is performed by the following procedure.
First, as shown in FIG. 3, the discharge pipe 18 of the filtration system is switched to be connected to the relay tank 13, and the relay tank 13 -the suction pipe 14 -the filtration device 16 (filter original plate 17a) -the discharge pipe 18 -the relay tank 13 A circulation channel is formed. Next, water is put into the relay tank 13 and the pump 15 is operated to start water circulation in the circulation passage. In addition, a filter aid for forming a precoat layer is added to the water in the relay tank 13. Filter aids include diatomaceous earth and microfibrous cellulose (Serish registered trademark). The filter aid added to the water enters the filter device 16 along the flow path and passes through each filter base plate 17a. At this time, the filter aid is caught on the filter base plate 17a, and the filter aid is accumulated on the filter base plate 17a. By repeatedly circulating the filter aid and adding the filter aid as needed, a precoat layer in which the filter aid is accumulated is formed on each filter base plate 17a. When it is confirmed that the precoat layer has been accumulated to an appropriate degree by the amount of filter aid added, the filtration resistance, etc., the filter 17 having the precoat layer formed on the filter base plate 17a is completed. Is possible.

However, the manufacturing method of the filter 17 has the following problems.
First of all, in the manufacture of the above filter, the filter aid is accumulated on the filter base plate to form a precoat layer. Therefore, how much precoat layer is necessary for the filtration of liquor, for example, how thick the filter aid is accumulated. Relying on the experience and intuition of the brewing maker, etc., was necessary to form the precoat layer. In addition, since the filter is manufactured using a filtering device, it can be manufactured only at a place where the filtering device is located, and the manufacturing of the filter itself takes time and labor, and there are limitations on the location.

  In addition, the precoat layer of the completed filter is very delicate because the filter aid is accumulated on the filter base plate by the water flow, so it needs to be handled with care, and bubbles are mixed into the circulating water. However, there was a problem that the part of the precoat layer hit by the bubbles was destroyed. Further, since the amount of water passing through the filter original plate of the filter device is not always uniform on the plane of each filter original plate, unevenness is caused in the precoat layer formed on the filter original plate due to uneven water flow. May occur, and uneven filtration of the filter may occur.

On the other hand, as a method for filtering liquor, there has been proposed a method for removing olivine and activated carbon using an ultrafiltration membrane without using an oliformant (Patent Document 1).
In addition, a method has been proposed in which the reduced supernatant is filtered with a fine porous hollow fiber having an average pore diameter of 0.01 to 1 μm (Patent Document 2).

JP-A-9-313162 JP-A-57-206378

  However, there are many sake breweries that use traditional traditional methods for producing sake, and there are also sake breweries that are particular about the production method that uses an ori-lowering agent. Moreover, in the filtration of patent document 1 and patent document 2, since it filtered using the ultrafiltration membrane and the hollow fiber, the component (polymer substance) which does not need to be removed is also removed, and alcohol The quality of the brewery can change unintentionally, and some breweries wish to continue using the filtration devices they have been using.

  On the other hand, even when a filtration apparatus is used, the above-described problem exists in the method of forming the precoat layer on the filter original plate each time. In addition, in other alcoholic beverages and liquid seasonings having a brewing process, for the filtration of impurities in the brewing process, a filter having a precoat layer formed is prepared in the same manner as the sake described above, and filtration is performed thereby. There are many cases. Thus, the present inventors have made studies on a filter that can effectively collect impurities without forming a precoat layer.

  In view of the above problems, an object of the present invention is to effectively filter impurities without using a precoat as a filter for filtering liquid impurities in a brewing process.

In order to achieve the above object, the invention of claim 1 is a filter for filtering liquid impurities in a brewing process, and is disposed on the downstream side of the first-layer fiber sheet disposed on the upstream side of the filtration flow path. A second-layer fiber sheet, the first-layer fiber sheet has a thickness of 75 μm or more and a density of 0.3 to 0.65 g / cm ³ , and the second-layer fiber sheet comprises: 60% by mass or more of lyocell having a thickness of 90 μm or more, a density of 0.3 to 0.6 g / cm ³ and a Canadian standard freeness of 350 ml or less, the fiber sheet and the second layer of the first layer The air resistance in a state where the fiber sheets are laminated is 30 sec or less.

The invention of claim 2 is characterized in that the second-layer fiber sheet contains 80% by mass or more of lyocell having a Canadian standard freeness of 200 ml or less.
The invention of claim 3 is characterized in that the liquid impurity filtration filter in the brewing step is an impurity filtration filter in the sake brewing step.

  The invention of claim 4 is characterized by comprising a reinforcing fiber sheet disposed on the downstream side of the fiber sheet of the second layer.

  According to the filter for filtering liquid impurities in the brewing process of the present invention, pre-coating is unnecessary and impurities can be effectively filtered.

The schematic diagram of a filtration system. The schematic diagram of filtration using a filtration apparatus system. The schematic diagram which forms a precoat layer in a filter original plate using a filtration device system. Explanatory drawing of the filtration test of the filter in this embodiment.

Hereinafter, an embodiment embodied in a filter for filtration used in the sake brewing process will be described.
The filter of the present embodiment is a filter used for filtration after brewing and / or lowering of sake, and the first layer fiber sheet located on the upstream side and the second layer located on the downstream side in the filtration device. It is made by overlapping the fiber sheet. Moreover, the fiber sheet for reinforcement arrange | positioned further downstream of a 2nd layer as needed can be provided.

  As a filter, by providing a fiber sheet of the first layer and a fiber sheet of the second layer, these two layers collect highly fluid impurities present in the liquor, and the first layer is collected by the second layer. It collects fine activated carbon that has passed through. In the present embodiment, hereinafter, the filter refers to a structure in which a first-layer fiber sheet and a second-layer fiber sheet are stacked, and the first-layer fiber sheet and second layer constituting the filter. These fiber sheets are simply expressed as a first layer sheet and a second layer sheet, respectively.

About the 1st layer sheet The fiber raw material which can be used for the 1st layer sheet is softwood pulp, hardwood pulp, these kraft pulp, bleached pulp, unbleached pulp, cotton linter, hemp, mulberry, sanjo, etc. Each fiber of plant pulp can be used.

  In addition to pulp, purified cellulose fiber, regenerated cellulose fiber, semi-synthetic fiber, synthetic fiber, and inorganic fiber can be used. The purified cellulose fiber includes lyocell fiber, and the regenerated cellulose fiber includes rayon fiber and cupra fiber. Semisynthetic fibers include acetate fibers and triacetate fibers, and synthetic fibers include nylon fibers, polyester fibers, acrylic fibers, polyvinyl chloride fibers, vinylon fibers, polypropylene fibers, polyethylene fibers, and composite fibers thereof. Examples of inorganic fibers include carbon fibers and glass fibers. These fibers may be used alone or as a mixture of a plurality of types, but softwood bleached kraft pulp (NBKP) is preferable from the viewpoint of cost.

  When a pulp material and lyocell are used for the sheet of the first layer, those subjected to beating treatment for enhancing paper strength can also be used. Beating can be performed with a known device such as a beater or refiner. As for the beating degree, the paper strength is enhanced when the Canadian standard freeness (CSF) is 650 to 300 ml for the pulp material and the CSF is 600 ml or less for the lyocell. When the regenerated cellulose fiber, semi-synthetic fiber, synthetic fiber, or inorganic fiber is used for the first layer sheet, one having a fineness of 0.1 to 2 dtx and an average fiber length of 2 to 20 mm can be used.

  About the method of processing these raw materials and making a 1st layer into a sheet | seat, although it is based also on the kind of raw material to be used, a wet manufacturing method and a dry-type manufacturing method are employable. As a wet manufacturing method, a manufacturing method using a circular net paper machine, a short net paper machine, a long net paper machine, or the like, which is a general paper manufacturing method, can be used. In the wet production, inorganic fillers such as diatomaceous earth and titanium oxide can be added. On the other hand, dry manufacturing methods include needle punch, air raid, melt blown, and the like, which are nonwoven fabric manufacturing methods.

  The thickness of the first layer sheet needs to be 75 μm or more. If it is less than this, the sheet of the first layer becomes thin, so the space for collecting and holding impurities decreases, the ability of the impurities to hold in the first layer decreases, and the sheet of the first layer temporarily captures it. The collected impurities escape and the filtration burden on the second layer increases, which may cause filtration leakage. The upper limit of the thickness of the first layer is not particularly defined from the viewpoint of the function of collecting and retaining impurities, but if it is too thick, the cost increases. The first layer sheet preferably has a thickness of 150 μm or more, more preferably 190 μm or more.

The density of the first layer sheet needs to be in the range of 0.3 to 0.65 g / cm ³ . If the density of the sheet is larger than this range, the fibers between the fibers in the sheet are clogged, so that the resistance during filtration increases, the filtration speed decreases, and the pressure applied to the filter tends to increase. On the other hand, if the size is smaller than this range, the fiber-to-fiber mesh becomes coarse, and the filtration speed increases. Filtration is not possible, and filtration leakage is likely to occur. Moreover, it is preferable that the density of the sheet | seat of a 1st layer exists in the range of 0.55-0.65 g / cm < ³ >.

The basis weight (g / m ² ) of the first layer sheet can be determined from the thickness and density, but is 25 g / m ² or more, preferably 50 g / m ² or more, more preferably 100 g / m ² or more. If so, since the sheet has a certain volume or more, it is possible to secure an impurity collection and holding space.

  The air resistance (JISP8117) of the first layer sheet can be in the range of 30 sec or less. When the numerical value is larger than this range, the filtration resistance of the first layer is increased, so that the filtration speed is lowered and the pressure applied to the filter is likely to be increased. A method for measuring the air resistance will be described in Examples. The same applies to the following air resistance.

  The maximum hole diameter of the first layer sheet can be in the range of 35 μm or less. If the maximum pore size of the first layer sheet is larger than this range, the impurities in the first layer sheet cannot be effectively collected, and the burden on the second layer sheet tends to increase. Moreover, a preferable range is 10 micrometers or less, and a more preferable range is 6 micrometers or less.

  The average pore diameter of the first layer sheet can be in the range of 10 μm or less for the same reason as the maximum pore diameter, the preferred range is 2.5 μm or less, and the more preferred range is 1.5 μm or less. The measuring method of the maximum pore diameter and the average pore diameter will be described in Examples.

About the second layer sheet The fiber material used for the second layer sheet needs to contain 60 mass% or more of lyocell. When the lyocell content is less than 60% by mass, effective collection of impurities cannot be performed. Moreover, the one where the content rate of a lyocell is higher is effective for collection of impurities, 70 mass% or more is preferable and 80 mass% or more is more preferable.

  Other fiber materials other than lyocell that can be contained in the second layer sheet at less than 40% by mass include softwood pulp, hardwood pulp, kraft pulp, bleached pulp, and unbleached pulp. In addition, each fiber of vegetable pulp such as cotton linter, hemp, mulberry, sanjo, etc., rayon, cupra, regenerated cellulose fiber, acetate, triacetate, semi-synthetic fiber, nylon, polyester, acrylic, polyvinyl chloride, synthetic fiber, Vinylon, polypropylene, polyethylene and the like can also be used. Fiber materials other than lyocell may be used alone, or a plurality of types may be mixed and used.

  The lyocell used for the second layer sheet needs to be beaten and used, and the beating degree needs to be a Canadian standard freeness (CSF) of 350 ml or less. If the value of CSF is higher than this, the eyes become rough, and effective collection of impurities cannot be performed. A smaller CSF value is more effective for collecting impurities, and a preferred range is 300 ml or less, and a more preferred range is 200 ml or less.

  Further, the fiber length of the lyocell to be used is not particularly limited, but it is possible to use one having a fiber length in the range of 2 mm to 10 mm before beating. If it is shorter than this range, the strength as a filter tends to decrease, and if it is longer, the fibers tend to be entangled with each other and the formation tends to deteriorate. The fineness of lyocell is not particularly limited, but 0.9 to 3.5 dtx can be used. If the fiber diameter is smaller than this, the strength of the filter tends to be lowered, and if it is larger, the pore diameter formed in the filter becomes larger even when beaten, and it becomes difficult to effectively collect impurities.

When a fiber material other than lyocell is required for the second layer sheet, the fiber conditions (degree of beating, fiber length, fiber diameter) that can be used are the same as those for the first layer sheet.
About the method of processing a raw material and making a 2nd layer into a sheet | seat, it is preferable to use a wet manufacturing method. In particular, in the second layer sheet, it is essential to contain 60% by mass or more of lyocell. In the dry production method, the sheet thickness is not uniform, and unevenness is likely to occur, and the density tends to be low and the hole diameter tends to be large. In addition, as a wet manufacturing method, a circular net paper machine, a short net paper machine, and a long net paper machine can be used. When performing wet manufacturing, inorganic fillers, such as diatomaceous earth and a titanium oxide, can be added like a 1st layer.

  The thickness of the second layer sheet needs to be 90 μm or more. If it is less than this, the sheet of the second layer becomes thin, so the space for collecting and holding impurities decreases, the ability of the impurities to hold in the second layer decreases, and the sheet of the first layer temporarily captures it. The collected impurities escape and the filtration burden on the second layer increases, which may cause filtration leakage. In addition, the upper limit of the thickness of the second layer is not particularly defined in terms of the function of collecting and holding impurities, but if it is too thick, the cost increases. The second layer sheet preferably has a thickness of 150 μm or more, more preferably 200 μm or more.

The density of the second layer sheet needs to be in the range of 0.3 to 0.6 g / cm ³ . If the density of the sheet is higher than this range, the fibers will become clogged, so that the resistance during filtration increases, the filtration speed decreases, and the pressure applied to the filter increases. Also, if it is smaller than this range, the eyes become rough, so the impurities that can be collected by the second layer sheet are reduced, and the impurities that have passed through the first layer sheet cannot be collected by the second layer. There is sex. Preference is given to a range of 0.3 to 0.55 g / cm ³ .

The basis weight (g / m ² ) of the second layer sheet can be determined from the above thickness and density, but if the sheet is 30 g / m ² or more, preferably 70 g / m ² or more, the sheet has a certain volume or more. It is possible to secure a space for collecting and holding impurities.

  The air resistance (JISP8117) of the second layer sheet can be in the range of 25 sec or less. If the numerical value is larger than this range, the filtration resistance of the sheet of the second layer is increased, so that the filtration speed is lowered and the pressure applied to the filter is likely to be increased.

  The maximum pore size of the second layer sheet can be in the range of 10 μm or less. If the maximum pore diameter is larger than this range, the impurities in the second layer sheet cannot be effectively collected, and filtration leakage may occur. Moreover, a preferable range is 6 micrometers or less, and a more preferable range is 4 micrometers or less.

The average pore diameter of the second layer sheet can be in the range of 8 μm or less for the same reason as the maximum pore diameter, the preferred range is 3 μm or less, and the more preferred range is 1.5 μm or less.
About the reinforcing fiber sheet The reinforcing fiber sheet as the third sheet can be arranged further downstream of the first layer sheet and the second layer sheet. This reinforcing fiber sheet is intended to reinforce the filter of the first layer and second layer sheets, for example, to prevent deformation of the filter that swells downstream due to a water pressure difference when the filter becomes clogged The reinforcing fiber sheet itself does not have to have a filtering function.

Further, in the filtration device configured to fix the filter to a metal plate (mesh) or the like, deformation of the filter is prevented by the metal plate, and therefore it is not necessary to use a reinforcing fiber sheet.
For the reinforcing fiber sheet, a cheap and excellent strength fiber material such as softwood pulp, hemp pulp, and polyester fiber can be used.

About the manufacturing method of the fiber sheet for reinforcement, although it depends on the kind of raw material to be used, the same wet manufacturing method and dry manufacturing method as the first layer and the second layer can be adopted.
The reinforcing fiber sheet is not particularly limited as long as it has no filtration performance and does not affect the filtration performance of the filter. Specifically, the air permeability resistance of the reinforcing fiber sheet is smaller than the air resistance of the filter. In addition, the reinforcing fiber sheet has a basis weight of 50 g / m ² or more and a specific tensile strength (JISP8113) of 20 N · m / g or more in order to prevent deformation of the filter against the water pressure during filtration. It is preferable.

  There is no particular limitation on the method of laminating the first layer sheet and the second layer sheet. For example, each sheet may be used in a state where it is simply overlapped at the time of use without being united and set on a filter frame or the like, and the sheets are bonded to such an extent that the flow path is not blocked during filtration. Also good. Adhesion may be performed by heat sealing using an adhesive, sewing, or a hot-melt adhesive material for the sheet material.

  Also, using a multi-tank paper machine, the first layer (second layer) is made in the first tank, the second layer (first layer) is made in the second tank, and these are made into the circular paper machine. It may be formed in two layers by laminating on the felt of the machine. Even when the third layer sheet is laminated on the first layer sheet and the second layer sheet, the lamination method is not particularly limited.

There is no particular limitation on the basis weight in the state where the first layer sheet and the second layer sheet are laminated to form a filter, and the basis weight of the first layer sheet and the basis weight of the second layer sheet can be taken respectively. Any sum of numbers may be used. In addition, if the basic weight which laminated | stacked the sheet | seat of the 1st layer and the sheet | seat of the 2nd layer is 100 g / m < ² > or more, the volume of a filter will be enough and it will become easy to obtain the collection of impurities and ensuring of holding space.

  The thickness of the first layer sheet and the second layer sheet laminated is not particularly limited, and the first layer sheet thickness (75 μm or more) and the second layer sheet thickness (90 μm or more) are respectively provided. What is necessary is just to be more than a lower limit. Note that both the first layer sheet and the second layer sheet are not completely flat and have undulations. Therefore, even if the thickness is measured by laminating both sheets, the sum of the thicknesses is not necessarily obtained. It is often an approximate value of.

  In a state in which the first layer sheet and the second layer sheet are laminated to form a filter, the air resistance needs to be in a range of 30 sec or less. When the air permeation resistance is larger than this value, the filtration resistance of the filter increases, so that the filtration speed is lowered and the pressure applied to the filter tends to increase. The range of the air resistance is preferably 10 sec or less, and more preferably 7 sec or less.

  The maximum pore diameter of the filter in which the first layer sheet and the second layer sheet are laminated can be in the range of 6 μm or less. If the maximum pore diameter is larger than this range, the efficiency of collecting impurities in the filter may be reduced. Moreover, a preferable range is 5 micrometers or less, and a more preferable range is 3 micrometers or less.

Further, the average pore diameter can be in the range of 3 μm or less for the same reason, the preferable range is 2 μm or less, and the more preferable range is 1 μm or less.
Specific examples are shown below.

Two types of pulp fibers were used: softwood bleached kraft pulp (indicated as “NBKP”) and hardwood bleached kraft pulp (indicated as “LBKP”).
As the lyocell fiber, Tencel (registered trademark) manufactured by Lenzing (fiber length: 4 mm, fineness: 1.7 dtx) was used.

As the polyester fiber, Kuraray Co., Ltd. EP043 (fiber length 3 mm, fineness 0.4 dtx) was used.
As the polypropylene fiber, PZ0.8 (fiber length 5 mm, fineness 0.8 dtx) of Daiwabo Polytech Co., Ltd. was used.

Preparation of filter Example 1
The first layer is made by mixing 50% by mass of NBKP beaten with CSF600 and 50% by weight of LBKP beaten with CSF600, and using a circular paper machine to dry the paper and drying it with a Yankee dryer. The basis weight is 105 g / m ^2. A sheet having a thickness of 196 μm, a density of 0.54 g / cm ³ , a gas permeability resistance of 3.5 sec, a maximum pore diameter of 9.8 μm, and an average pore diameter of 3.1 μm was obtained.

A refiner was used for beating the fiber, and the beating degree (CSF) was measured by JISP8121 (pulp-freeness test method). As for the basis weight, the mass per 1 m ² of the sheet was measured with an electronic balance. The thickness of the sheet was an average value obtained by measuring any 10 points of the sheet with a microthickness gauge (peacock, type: H) manufactured by Ozaki Mfg. Co., Ltd. The density of the sheet was calculated from the basis weight / thickness. The air resistance was measured by JISP 8117 (paper and paperboard, air permeability and air resistance test method) using a Gurley densometer manufactured by Toyo Seiki Seisakusho. The maximum pore size and the average pore size were measured using a palm porometer CFP-1100 (measurement solution SILWICK) manufactured by PMI.

  It should be noted that the second layer sheet, the filter in which the first layer and the second layer are laminated, and the sheets of other examples and comparative examples are also used in the first layer by using these methods and apparatuses. The measured physical property values were measured. Hereinafter, units are omitted for basis weight, thickness, density, air resistance, maximum pore diameter, and average pore diameter, and only numerical values are shown.

  The second layer is made from 100% by mass of lyocell fiber beaten to CSF200, and then paper-made and dried in the same manner as in the first layer, basis weight 70, thickness 166, density 0.42, air resistance 4 4. A sheet having a maximum pore size of 4.7 and an average pore size of 1.4 was obtained.

  The first layer and the second layer were overlapped to form the filter of Example 1. In the stacked state (temporary fastening with clips, the same applies hereinafter), the basis weight was 175, the thickness was 362, the air resistance was 8.6, the maximum pore size was 2.5, and the average pore size was 1.0. The thickness in the laminated state is not necessarily the sum of the thickness of the first layer and the thickness of the second layer because both the first layer and the second layer have fine undulations.

Examples 2 to 16
In Examples 2 to 16, sheets were produced by the same method as in Example 1 using the raw materials shown in Table 1 below as the first layer and the second layer. Also, the basis weight, thickness, density, air permeability resistance, maximum pore diameter, average pore diameter of the first layer and the second layer, and a filter in which the first layer and the second layer are stacked (indicated as “laminated” in the table) Table 1 below also shows the basis weight, thickness, air resistance, maximum pore diameter, and average pore diameter.

  In Table 1, N in the raw material column is NBKP, L is LBKP, T is Tencel, E is polyester, and PP is polypropylene. The blending ratio of the raw materials is shown in Table 1 as a numerical value following the raw material alphabet. For example, “N50 / L50” in the raw material column of the first layer of Examples 1 to 5 means that 50% by mass of NBKP and 50% by mass of LBKP were mixed to form a raw material, and the raw material column of the first layer of Example 7 “N100” means that 100% by mass of NBKP was used as a raw material.

  When the raw materials were beaten, the beating degree of each raw material was displayed in the CSF column of Table 1 in the order displayed in the raw material column. For example, “200/550” in the CSF column of the second layer of Example 16 indicates a tencel (70 mass%) with a beating degree of 200 and a beating degree of 550 from the display of “T70 / N30” in the raw material column. It means that NBKP (30% by mass) was used as a raw material. In addition, the raw material which has not been beaten is not described in the CSF column. For example, 20% by mass of the polyester used in the first layer of Example 6 (indicated as “E20” in the raw material column in Table 1) is not subjected to beating treatment, so “−” is displayed in the CSF column in the table. No numerical value is displayed.

Comparative Example 1
A single-layer filter using only the same sheet as the second layer of Example 1 was used. In Table 2 below, the column of the second layer is shown for convenience.

Comparative Example 2 (background technology) was obtained by laminating 100 g / m ^{2 of} serisch (Daicel Finechem Co., Ltd. serisch (registered trademark)) on the sheet shown in the second layer column of the table using a conventional technique. Diatomaceous earth (Kawakita Chemical Co., Ltd. K Light) was laminated at 80 g / m ² to form a precoat layer, which was used as a filter.

  As shown in the column of the second layer in Table 2, the precoat layer had a basis weight of 180, a thickness of 1000, and a density of 0.18. In addition, the precoat layer of this comparative example 2 is formed using a filtration apparatus, and since it cannot take out a precoat layer and can measure the air resistance, a maximum hole diameter, and an average hole diameter, it is unmeasured. Further, the filter of Comparative Example 2 had a basis weight of 230 and a thickness of 1190.

  In Comparative Examples 3 to 17, sheets were produced by the same method as in Example 1 using the raw materials shown in Table 2 below as the first layer and the second layer. Also, the basis weight, thickness, density, air permeability resistance, maximum pore diameter, average pore diameter of the first layer and the second layer, and a filter in which the first layer and the second layer are stacked (indicated as “laminated” in the table) Table 2 also shows the basis weight, thickness, air resistance, maximum pore diameter, and average pore diameter. The display method of Table 2 is the same as that described in Table 1.

Test 1-4
For the filters of these Examples and Comparative Examples, the following Test 1 to Test 4 were performed.

Test 1 (activated carbon filtration test)
About the filter of each Example and a comparative example, the filtration test of activated carbon was done as a test corresponding to the filtration after orientation pulling. A stainless steel holder KST-47 (effective filtration area 12.5 cm ² ) with a tank manufactured by Advantech Toyo Co., Ltd. was used as a filtration test apparatus. The first layer sheet and the second layer sheet are each cut into a circle having a diameter of 47 mm, and these two sheets (comparative example 1 is a single layer and comparative example 2 is a conventional filter with a precoat layer) are stacked. A test filter was set in the filtration test apparatus so that the first layer was on the upstream side (FIG. 4). Further, test solution 1 in which 0.2 g of activated carbon for brewing (Kawak Chemical Co., Ltd. (registered trademark) activated carbon SE, average particle size of 27 μm, particle size distribution of 0.5 to 150 μm) was added to 200 ml of an ethanol 20% by mass aqueous solution and mixed. Was made.

  As shown in FIG. 4, the test liquid 1 was put into the tank of the filtration test apparatus 20, and the test liquid 1 was filtered with a test filter set in a state where the inside of the tank was pressurized to 0.3 MPa. Note that the pressure of 0.3 MPa is a reproduction of the pressure applied to the filter when the liquor after the orientation is filtered using a conventional filtration device.

  The filtrate that passed through the test filter was collected in a container 21, and 20 ml of this filtrate was further filtered with a membrane filter 23 (A045A025A, manufactured by Advantech Toyo Co., Ltd., pore size 0.45 μm) that is a microfiltration membrane attached to a syringe 22. After filtration, the surface of the membrane filter 23 was visually observed and magnified (10 times) with a microscope to observe whether activated carbon was present on the surface. When activated carbon is confirmed on the surface of the membrane filter 23, it means that the activated carbon in the test liquid 1 has passed through without being collected by the test filter.

  This test 1 was performed on the test filters of the examples and comparative examples. For membrane filter 23, activated carbon could not be confirmed visually, and when activated with a microscope, activated carbon could hardly be confirmed with “◎”. Activated with a microscope, activated carbon could be confirmed, but only a small amount has no practical problem Was marked as “◯”. Moreover, what was able to confirm activated carbon with thinness visually was evaluated as "(triangle | delta)", and what was able to confirm activated carbon completely visually was evaluated as "x" (Table 3). In addition, as for evaluation, “○” and “◯” are acceptable, “Δ” and “×” are unacceptable, and the same applies to other tests.

Test 2 (activated carbon and floc filtration test)
Next, the filter of each Example and Comparative Example was subjected to a filtration test of activated carbon and floc (aggregates formed by binding an orientation reducing agent to the orientation) as a test corresponding to filtration after the orientation reduction. Using the same filtration test apparatus 20 as in Test 1, a test filter prepared in the same manner was set. Moreover, 200 ml of 20 mass% ethanol aqueous solution, the same activated carbon 0.2g as the test 1, and 20 ml of floc containing liquid were added and mixed, and the test liquid 2 was produced. The floc-containing liquid is a liquid containing a pseudo flock prepared by adding and mixing 0.5 g of gelatin dry weight and 2 g of commercially available strawberry astringent juice as an orientation-lowering agent in 200 ml of sake. 20 ml was collected in a state in which no floc or the like was precipitated.

  The test solution 2 is filtered through a test filter in the same manner as in test 1, and the filtrate is further filtered through a membrane filter 23 as in test 1, and the filtered membrane filter 23 is magnified (10 times) with a microscope. The presence of activated carbon or floc on the surface was confirmed. When activated carbon or the like can be confirmed on the membrane filter 23, it means that the activated carbon or the like in the test solution 2 has passed without being collected by the test filter.

  This test 2 was conducted on the filters of the examples and comparative examples. About the membrane filter 23, activated carbon etc. could not be confirmed visually, and even if it was magnified with a microscope, activated carbon etc. could not be almost confirmed. “◎”, activated carbon etc. could be confirmed when magnified with a microscope. Those without were marked as “O”. In addition, “△” indicates that the activated carbon etc. can be visually confirmed as thin, and “x” indicates that the activated carbon can be completely confirmed visually (Table 3).

Test 3 (filtration rate test)
Furthermore, about the filter of each Example and the comparative example, the filtration rate was measured about each of the filter for an unused test, and the filter for a test after using it for the test 2. FIG. An unused test filter (unused filter) was set in the filtration test apparatus used in each of the above tests, and the amount of water (ml / min) passing through the unused filter per minute was measured. . The pressure in the tank was 50 kPa. As a result of the measurement, the passing amount (ml / min) was “◎” for 600 or more, “◯” for 300 to 599, “Δ” for 200 to 299, and “x” for 199 or less. This is based on the filtration rate (217 ml / min) of Comparative Example 2 which is the prior art, and “◎” and “◯” are cases where the filtration rate is sufficiently faster than this.

  Further, a test filter (used filter) after the same test was used in Test 2 was also performed. As a result of the measurement, the passing amount (ml / min) was “◎” for 100 or more, “◯” for 60 to 99, “Δ” for 30 to 59, and “x” for 29 or less. This evaluation is also based on the filtration rate (33 ml / min) of Comparative Example 2 which is a conventional technique (Table 4).

Summary of Tests 1-3 The results of the following Tests 1-3 are summarized in Table 5.

From the tests 1 to 3, the following can be understood.

  The filters of Examples 1 to 16 showed good results in filtration tests (Test 1 and Test 2) of an aqueous ethanol solution containing activated carbon and activated carbon and floc. In addition, the filters of Examples 1 to 16 were able to obtain a good filtration rate even in a filtration rate test (Test 3) in an unused state and in a state where activated carbon or floc was collected in the filter.

  On the other hand, in the filter of the comparative example, Comparative Example 2 (conventional filter having a precoat layer formed), 6, 7, and 13 are filtration tests of an aqueous ethanol solution containing activated carbon, activated carbon and floc (Test 1 and Test 2). Was a good result. However, a good filtration rate was not obtained in the filtration rate test (test 3) in a state where the filter was not used and in a used state where activated carbon and floc were collected in the filter.

  In Comparative Examples 1 to 5, 8, 9 to 12, and 14 to 17, good results were not obtained in the filtration test (Test 1 and Test 2) of an aqueous ethanol solution containing activated carbon, activated carbon, and floc. In particular, Comparative Examples 5 and 17 did not give good results in both the filtration test (Test 1 and Test 2) and the filtration rate test (Test 3).

Test 4 (Confirmation test using a brewer's filtration device)
For some of the examples and comparative examples, we conducted a verification test of liquor using a filtration device of the same manufacturer at a plurality of brewers, leakage of activated carbon, leakage, workability / filtration time, filter state after filtration Judged.

  First, at Company A, the filter after Example 1 was filtered using the filter of Example 1 in a filtration device (filter press) normally used by the company (1 of 4). In addition, using the filters of Example 1, Comparative Example 1 and Comparative Example 2, the liquor after the orientation was lowered (filtration after the orientation was performed) was filtered (4-2, 4-3, 4-4). . The orientation reducing agent used for this orientation reduction is the one used by each brewing manufacturer. In addition, the filter of the comparative example 2 was produced using the filtration apparatus used for filtration as described in background art.

  Next, at Company B, the liquor after the orientation was filtered using the filter of Example 1 (device name) using the filter of Example 1 (4-5). Furthermore, at company C, the liquor after orientation was filtered using the filter of Example 1 (device name) using the filter of Example 1 (4-6). Since these tests use a filtration device owned by each company, the pressure during filtration and the size of the filter (length of one side) differ depending on the type of filtration device and filtration.

  In Test 4, 20 ml of the filtered filtrate that passed through each filter was collected and further filtered with the same membrane filter as in Tests 1 and 2, and the filtered membrane filter was magnified with a microscope to check for the presence of activated carbon or floc on the surface. confirmed. The case where the activated carbon and the orientation could not be confirmed visually was indicated as “◯”, and the case where the activated carbon and the orientation were confirmed visually was designated as “X”.

  In addition, regarding filter installation workability and filtration time using a filter, “○” indicates that the filter is superior to “Background” (Comparative Example 2), and “X” indicates that the filter is inferior.

Furthermore, it was visually determined whether the surface of the filtered filter (Comparative Example 2 is a filter on which a precoat layer was formed) was “uniform” or “non-uniform”.
In Test 4 by each of these brewers, Example 1 is evaluated that there is no leakage of activated carbon and soil, and workability / working time is good in filtration after orientation-drawing and orientation-lowering (2 in 4-1, 4-2). 4-5, 4-6) and the prior art (4-4). On the other hand, in Comparative Example 1, a side leakage occurred in the filtration after the side reduction (3 of 4).

  The test results at each of these brewers were consistent with the results of the previous tests 1 to 3 (Table 6).

In addition, the said embodiment is only what showed one Embodiment of this invention, and the content of this invention is not limited to this embodiment.

  For example, in the present embodiment, it has been described as a filter for filtering sake. However, alcoholic beverages other than sake are brewed liquor, distilled sake, mixed sake brewing process filtration, and liquid seasonings such as mirin and soy sauce other than alcoholic beverages. You may use for filtration of brewing processes, such as ingredients. Although explanation was made using rice as a raw material, the raw material for brewing is not particularly limited.

10 ... Raw wine tank, 11 ... Upper piping, 12 ... Lower piping, 13 ... Relay tank, 14 ... Suction piping, 15 ... Pump, 16 ... Filtration device, 17 ... Filter, 17a ... Filter base plate, 18 .... Pipe for discharge, 19 .... Recovery tank, 20 .... Filtration test device, 22 .... Syringe, 23 ... Membrane filter.

Claims (4)

A filter for filtering impurities in a liquid in a brewing process,
A first-layer fiber sheet disposed on the upstream side of the filtration channel, and a second-layer fiber sheet disposed on the downstream side,
The fiber sheet of the first layer has a thickness of 75 μm or more and a density of 0.3 to 0.65 g / cm ³ .
The fiber sheet of the second layer contains 60% by mass or more of lyocell having a thickness of 90 μm or more, a density of 0.3 to 0.6 g / cm ³ and a Canadian standard freeness of 350 ml or less,
A filter for filtering impurities in a liquid in a brewing process, wherein the air permeability resistance in a state where the fiber sheet of the first layer and the fiber sheet of the second layer are laminated is 30 sec or less. The fiber sheet of the second layer is
2. The filter for filtering impurities in a brewing process according to claim 1, wherein the lyocell having a Canadian freeness of 200 ml or less is contained in an amount of 80% by mass or more.   3. The filter for filtering liquid impurities in a brewing process according to claim 1, wherein the filter for filtering impurities in a liquid in the brewing process is a filter for filtering impurities in a brewing process of sake. 4. .   4. The filter for filtering impurities in a brewing process according to claim 1, further comprising a reinforcing fiber sheet disposed on the downstream side of the fiber sheet of the second layer. 5.