JP2020131067A - Production method and production apparatus of paper material from waste gypsum board separation paper as raw material - Google Patents

Abstract

To provide a production method of a paper material where an attached gypsum amount is made extremely slight or zero without burning a waste gypsum board and separation and scattering can be suppressed even when attached gypsum remains.SOLUTION: A production method of a paper material from paper pieces separated from a waste gypsum board as a raw material includes: a crushing step 12 crushing the waste gypsum board 11 to prescribed shapes and sizes; a paper piece recovery step 13 separating and recovering the paper pieces from a crushed material; an underwater agitation and crushing step 14 generating a pulp liquid by charging the separated paper pieces into water, dispersing and suspending a plant tissue in water by unstiffening and eluting a water-soluble component and the like; a pulp recovery step 15 separating the pulp by separating gypsum, easily freed pulp, the water-soluble component and the like and water contained in the pulp liquid; and a paper material molding step 16 molding the pulp to a prescribed shape; and a drying step 17 drying the molded paper material at a prescribed temperature.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method and apparatus for manufacturing a paper material using waste gypsum board separation paper as a raw material, and a litter for animals. More specifically, a piece of paper is separated from a waste gypsum board material (hereinafter referred to as waste gypsum board). The present invention relates to a method and apparatus for manufacturing a paper material using the piece of paper (hereinafter referred to as waste gypsum board separation paper) as a raw material, and an animal litter using the paper material.

Gypsum board is made from baked gypsum (semi-water gypsum) as the main raw material, mixed with sawdust, pearlite, foaming agent, etc., kneaded with water to make a paste, poured between two base papers, and hardened into a plate. Since it is a gypsum board, has excellent fire resistance, sound insulation, non-stretchability, and is inexpensive, it has long been used for interior materials such as buildings, such as walls, partitions, and ceilings of houses. In recent years, due to the evolution of its manufacturing technology and construction method and the development of new materials, gypsum board with various performances, for example, gypsum board with waterproof treatment on both sides of base paper and gypsum core, and gypsum Reinforced gypsum board with enhanced fire resistance by adding glass fiber to the core, semi-penetrated embossed gypsum lathboard on the base board for painted walls of Japanese-style houses, decorative gypsum board with decorative surface, and small holes A wide variety of boards, such as perforated gypsum board for sound absorption, which exerts an excellent sound absorption effect in the mid-low range, have been developed and commercialized, and are used in large quantities in a wider range.

Since hundreds of thousands of tons of such gypsum board are manufactured and used annually, the used gypsum board will be scrapped and discharged in large quantities in the future. In the case of a new board, this waste material is generated as waste material such as scraps and scraps (hereinafter referred to as new construction waste material) when it is cut to a predetermined size and used at a new construction site such as a house. Also, in the dismantling of existing buildings, the dismantled material is generated as waste material (hereinafter referred to as dismantling system waste material), and now the latter is generated in a larger amount than the former, and will continue to be generated in the future. It is expected that this tendency will continue and more waste materials will be generated.

Of these waste materials, some of the new construction waste materials are reused as raw materials for the production of new gypsum board, but the remaining new construction waste materials and disassembly system waste materials are landfilled as industrial waste in the same way as other waste products. It has been disposed of. However, this landfill disposal is required by law to be disposed of at a controlled disposal site because the waste gypsum board is metabolized by sulfate-reducing bacteria that live in groundwater and causes the generation of toxic hydrogen sulfide. .. On the other hand, the management type disposal site is tight, and it is becoming difficult to secure it especially in the suburbs of the city year by year, and securing this disposal site has become a big environmental and social problem.

Under these circumstances, efforts are being made to recycle (recycle) waste gypsum board instead of landfilling it. However, the following issues have been pointed out.
There is a potential understanding among the general public that recycled products should be cheaper than virgin wood, while the reality is that processing costs are higher than expected, which is reflected in recycled products. Recycling of waste gypsum board is hesitant because it is expensive, and most of it is buried in a controlled final disposal site. It is prohibited to bury it at a stable final disposal site.

In addition, some gypsum boards contain harmful substances such as asbestos, arsenic, and cadmium, so it is necessary to deal with them. Currently, some of these treatment technologies and additives have been put into practical use. However, the processing cost is high, which is an issue for recycling. In the past, there have been various problems with this harmful substance, which has hindered the expansion of sales channels for recycled products.

In addition, regarding the recycling of release paper that is peeled off from waste gypsum board, part of it is used as a raw material for manufacturing recycled paper, but the general understanding is that it is recycled in the same way as the recycling of gypsum. Since the products are expensive, the recycling of release paper is hesitant, and most of them are buried in incineration or controlled final disposal sites. Currently, this release paper is partly converted to RPF (solid fuel made from waste plastics as the main raw material) and used, but there are restrictions such as fluctuations in supply and demand depending on the market price and the cost of separating gypsum. There is an urgent need to expand applications other than RPF.

Under this circumstance, some companies have been conducting research and development on the recycling of waste gypsum board, and the results have been proposed in several patent documents.

The following Patent Document 1 (Patent No. 4035419) describes a method for separating a piece of paper from a waste gypsum board, a separating device, and an animal bedding using the separated piece of paper. This paper piece separation method includes a crushing step of crushing a waste gypsum board to a size suitable for firing, a firing step of firing a crushed waste gypsum board, and a gypsum-attached paper piece and gypsum on the waste gypsum board fired in the firing step. A preliminary sieving step for separating into gypsum, a transport step for air-transporting the gypsum-attached paper pieces separated by the preliminary sieving step, and a sieving step for separating the gypsum and the paper pieces separated from the air-transported gypsum-attached paper pieces. A piece of paper is separated from the waste gypsum board through a series of these steps.

According to this paper piece separation method, waste gypsum board is crushed and then fired to turn dihydrate gypsum into hemihydrate gypsum, which is subjected to an air transportation process and sieved with a simple ordinary sieve to separate the gypsum and paper. At that time, a piece of paper with a small amount of adhered gypsum (semi-hydrated gypsum) can be efficiently separated and collected. In addition, by firing the waste material at a temperature of 100 ° C. or higher, mold and mites attached to the waste material can be sterilized or killed. Therefore, the paper pieces separated and collected after that can be safely used for bedding such as barns, especially for agriculture. Can be reused.

Further, the following Patent Document 2 (Japanese Patent No. 3221940) describes a method of recovering gypsum from the waste material of gypsum board, wherein the gypsum board base paper is attached to at least a part of the gypsum board core. The one that heats the waste material to carbonize the base paper is described.

Further, the following Patent Document 3 (Japanese Patent No. 3221939) describes a method of recovering gypsum board base paper and gypsum from waste gypsum board material, in which gypsum board base paper adheres to at least a part of the gypsum board core. After heating the waste material of the gypsum board, water is applied to separate the base paper from the gypsum core, and the base paper and the gypsum constituting the gypsum core are collected.

Furthermore, the following Patent Document 4 (Patent No. 4371801) describes a method for producing α-type hemihydrate gypsum from waste gypsum board and a method for collecting base paper for gypsum board. This recovery method is a method in which a waste gypsum board is wet-heat-treated under pressure to separate the gypsum core transferred to α-type hemihydrate gypsum from the base paper for gypsum board, in hot water or in a steam atmosphere. It is characterized by doing. According to this method, gypsum without paper (paper pieces and paper fibers) and base paper without gypsum adhesion are collected from waste materials, and are effective as raw materials for manufacturing gypsum building materials, used paper, agriculture and other industries. Can be used for.

Furthermore, the following Patent Document 5 (Japanese Unexamined Patent Publication No. 2001-294496) describes a technique in which the paper in the waste gypsum board can be used as a water adjusting material for cow manure in the production of compost. This technique is a method for producing compost, which comprises separating gypsum and paper from the waste material of gypsum board and then using the paper as a water adjusting material for manure of livestock, and crushing the waste material of gypsum board. The gypsum and the paper are separated, and the separated paper is crushed again to remove the gypsum adhering to the paper, and then the paper is used as a moisture adjusting material. According to this method, the period until ripeness can be significantly shortened as compared with the case of the conventional compost production method in which sawdust is used as a moisture adjusting material, and further, it is treated as waste in the past. It has the effect of reusing the collected paper from the waste gypsum board.

This waste gypsum board separation paper is used for animal litter as described in the above patent document. On the other hand, general used paper such as newspapers and magazines is also used for such litter. This used paper litter also generally has many problems, such as mud-cleaning, resilience / cushioning and water absorption / water retention, as well as deterioration of the working environment in the barn. The litter that has been devised is also introduced in the patent literature.

For example, in Patent Document 6 below (Japanese Unexamined Patent Publication No. 58-20131), it is stated that waste paper or waste pulp is cut and crushed material is humidified and granulated to obtain most of the cotton-like particles having a particle diameter of 3 to 10 mm. The characteristic bedding material for livestock is disclosed. According to this, the animal does not cause bronchitis or otitis because it does not generate dust, and because it has the ability to retain and absorb sufficient water, it is not possible to collect urine due to urination, and the amount used is rice straw. Can be reduced to about 1/2. In addition, since the main material is pulp such as used paper, it is possible to make a soft and warm bed, and it can be mass-produced at the factory regardless of the season or natural condition, so it can be supplied stably and inexpensively. In addition, since the flooring material after use is plant fiber, the effect of being able to reuse it as high-quality compost can be obtained.

Further, in the following Patent Document 7 (Patent No. 2931591), paperboard or laminated paper is crushed into an indefinite shape in the range of 1 to 50 mm in length and width, and the peripheral edge is fluffed as if pulp fibers were torn off to make manure. Disclosed is a paper litter for livestock that has excellent absorption sustainability, heat insulation, and bactericidal properties.

Further, in Patent Document 8 below (Japanese Unexamined Patent Publication No. 2000-263011), used paper is boiled, crushed and dehydrated, and heat-dried to have good cushioning properties, such as bovine mastitis and hog cholera. Manufacturing method of water absorbing material used for treatment of bedding for livestock barn, shochu effluent, sludge, etc., which can efficiently prevent classical swine fever, etc., and can be disposed of by carbonization after use, and used water absorption A method of treating the material is disclosed.

Furthermore, in the following Patent Document 9 (Japanese Unexamined Patent Publication No. 11-239426), the longest portion of used paper is crushed from 1 mm to 30 mm to form a litter, and if necessary, a coloring material, a deodorant, bacteria, and soil are used. Livestock breeding with excellent water absorption, heat insulation, and bactericidal properties for manure by adding a function by mixing or spraying an improved material, a surfactant, or a superabsorbent polymer and a porous compound. The litter fee is disclosed.

Furthermore, the following Patent Document 10 (Japanese Unexamined Patent Publication No. 2015-16440) describes a methane fermentation method, a straw material and a litter. This methane fermentation method is a method in which straw is crushed into fragments of 10 mm to 100 mm and methane fermentation is carried out at a temperature of 50 ° C. or higher. According to this method, hygienic straw materials and litter can be provided as compared with those conventionally crushed to the order of microns, and a sufficient amount of biogas can be recovered by methane fermentation.

Japanese Patent No. 4035419 Japanese Patent No. 3221940 Japanese Patent No. 3221939 Japanese Patent No. 4371801 Japanese Unexamined Patent Publication No. 2001-294496 Japanese Unexamined Patent Publication No. 58-20131 Japanese Patent No. 2931591 Japanese Unexamined Patent Publication No. 2000-263011 JP-A-11-239426 Japanese Unexamined Patent Publication No. 2015-16440

Separation / recovery of gypsum and paper pieces from the waste gypsum board described in Patent Documents 1 to 4 is carried out through steps such as firing, heating (paper carbonization), and pressure wet heating of the waste gypsum board. However, these treatment methods and treatment equipment are complicated and generally large-scale treatment facilities, which require a large amount of capital investment and aggravate running costs such as fuel costs, which are reflected in the price of recycled products and are expensive. Therefore, it is difficult to obtain a profit commensurate with the investment, and there is a problem in profitability.

In addition, the paper pieces are also expensive and cannot be expected to expand in use, and since the paper pieces are in a state where the paper shape is maintained and the gypsum adheres to the paper surface, the gypsum can be easily separated. There is. In addition, the gypsum to be separated is dihydrate gypsum (needle-shaped structure), which is heated at a predetermined temperature to make hemihydrate gypsum or anhydrous gypsum, which is easily separated and collected. It adheres and remains in the form of anhydrous gypsum.

By the way, if gypsum (particularly semi-water or anhydrous gypsum) adheres to and remains on a piece of paper, it may separate and scatter during use, and in particular, it may become finely divided into dust and scatter around, causing damage and making it impossible to use safely and securely. For example, if humans inhale this dust, it may have an adverse effect on health, and if it is used for livestock bedding such as dairy cows, it may be inhaled by dairy cows and have the same adverse effect. The same problem applies to use in other industrial fields. The litter of Patent Document 5 also has the same problem.

In addition, litter using ordinary used paper has the same problem. For example, in the litter of Patent Document 6, waste paper and waste pulp are cut into a cotton shape of about 0.5 mm or less, sieved to remove fine particles of 10 μm or less, sprayed and humidified with water, and subjected to a granulator. Since most of the cotton-like particles are flexible porous cotton-like particles having a particle diameter of 3 to 10 mm, they can be easily separated in whole or in part during laying and when the animal moves. Cotton-like particles of 10 μm to 0.5 mm are scattered. In addition, the cotton-like particles that are scattered or scattered and accumulated on the floor surface stick to the floor surface when wet with manure, and since the paper contains water-soluble components, etc., it dissolves when it absorbs water and becomes viscous. Since it is imparted, it becomes muddy or clay-like (hereinafter, also referred to as sticky) and stains the floor surface, and on the other hand, it becomes difficult to collect the litter containing manure. Therefore, when it is used as an animal dressing having a large amount of water in manure such as dairy cows, it cannot be used alone, but is mixed with sawdust or the like.

If a binder is mixed during granulation to improve the stability of the particles, scattering of cotton-like particles can be suppressed, but if a water-soluble binder such as carboxymethyl cellulose, which is commonly used, is used, water absorption is achieved. As a result, the binder itself dissolves, not only the shape cannot be maintained, but also the floor surface becomes more sticky. In addition, a polymer such as polyvinyl alcohol, which is water-soluble but becomes water-insoluble once dried, has a film-forming property. Therefore, when this is used, a film is formed on the surface of cotton-like particles, and a porous portion between fibers is formed. In addition to reducing water absorption after use, there is a risk that it will remain as a persistent substance when it is collected as manure after use and then made into compost or the like.

Further, the paper dressing of Patent Document 7 also has the same problem as that of Patent Document 6 because the paper is crushed by a dry method and the peripheral portion is fluffed. Further, the paperboard and the laminated paper absorb more water than the relatively thin paper such as copy paper, but retain more water on the surface and in the gaps between the papers. Further, by fluffing the peripheral edge, more water can be stored in the fluffed portion. Therefore, at first glance, the water absorption is high. However, the water retained on the paper surface, between the papers, and on the fluffy peripheral edge is easily dispersed to the surroundings due to the movement of the litter due to the movement of animals or the like. In particular, since a large amount of water flows out when collecting the litter containing manure, the workability of the collection work is poor, and the odorous components (mainly ammonia components) in the water that have flowed out or scattered are scattered at once. , There is a risk of deteriorating the environment inside the barn.

Furthermore, the manufacturing method of Patent Document 8 has the same problems as those of Patent Document 6. In particular, since the used paper is soaked in water or warm water or boiled, water-soluble components and the like dissolve, but when boiled, components that are difficult to dissolve in water also dissolve. In the use of general animal bedding, these components do not dissolve because hot water is not used, but once the components that have been dissolved by boiling remain, they are easily dispersed by water. It is necessary to sufficiently separate and remove these dissolved components and the components generated by pulverization.

Furthermore, the litter of Patent Document 9 has the same problems as those of Patent Documents 6 and 7 because a relatively large number of flat surfaces of the paper remain because the used paper is crushed by a dry method. In particular, when kneading or bending, more water is stored between the bent paper surfaces, so when the bedding moves due to the movement of animals, the retained water is easily dispersed around. In addition, when a surfactant is applied to waterproofed paper to develop water absorption, water retention is performed only on the paper surface, and as will be described later, a large amount of water is retained on the surface. Therefore, more water is dispersed to the surroundings due to the movement of the litter. Furthermore, since used paper is generally collected by being bundled or messed up, it is difficult to evenly impart hydrophilicity to the entire surface even if a surfactant is sprayed. In addition, after crushing, the shape becomes irregular and it becomes even more difficult to knead or bend it. Further, even if it can be applied to the whole, since the surfactant is generally used by adding several weight% to water, the water content of the paper after application becomes high and the function as a water absorbing material is lost. There is a risk.

Since solid particles such as porous compounds are easily separated from the litter, when the litter is recovered, it sticks to the floor surface and the recovery work becomes difficult.

Furthermore, the litter of Patent Document 10 is a method of crushing straw to a predetermined size and fermenting methane at a predetermined temperature, but in recent years, the straw material is insufficient, and it is expensive and difficult to obtain stably. ing.

From the above, the recycling of waste gypsum board is hesitant or stagnant due to the fact that the total cost is soaring due to large-scale and expensive processing facilities and running costs, and it is not profitable. There is an urgent need to reduce it. On the other hand, gypsum adheres to and scatters on the separated pieces of paper, which limits the range of use, and the amount of waste gypsum board, which is the raw material, varies greatly depending on the region, and is generally around urban areas. There is a tendency that the number of paper materials is high and low in rural areas, and that the amount varies depending on the season.

Therefore, the present inventors have simplified the processing method or the processing apparatus of the prior art to reduce the processing cost, and how can the amount of gypsum adhering to the piece of paper be reduced to zero or still remain. I have been eagerly searching through trial and error to see if it can be prevented from being separated from the piece of paper and scattered. As a result, the processing facility simplifies the process by eliminating the need for steps such as the firing process so that the pieces of paper can be separated, while the pieces of paper to which gypsum has adhered can be returned to pulp once in water and treated to remove the remaining adhered gypsum. The gypsum that can be easily and inexpensively removed, and the gypsum that remains without being removed can be sunk (embedded) between the pulp fibers in the form of dihydrate gypsum that is difficult to pulverize, and the gypsum that remains on the surface is also fine powder. Since it is difficult to disperse, it can be prevented from separating and scattering, making it safe, and when using a piece of paper from which gypsum has been separated as a litter for animals, work in the barn, which is a problem with general used paper. As a result of diligent search for improvement of the environment, it can be prevented by efficiently separating the gypsum and water-soluble components that are easily released and scattered during crushing and forming a molded body with a predetermined shape, while also the original raw material. We came up with the idea that the lack of fluctuation in the waste gypsum board could be solved by replenishing used paper, and completed the present invention.

Therefore, an object of the present invention is to reduce the amount of gypsum adhering to a piece of paper separated from the waste gypsum board to a minimum or substantially zero by a simple processing step and an inexpensive device without firing the waste gypsum board, and to achieve residual adhesion. Even so, it suppresses separation and scattering as gypsum powder, especially suppresses scattering as dust, and also removes paper powder that is easily released from the paper material and water-soluble components adhering to the paper. It is an object of the present invention to provide a method and a manufacturing apparatus for manufacturing a paper material which can be separated / removed, used safely and securely, and which is profitable for recycling.

Another object of the present invention is to achieve the above-mentioned object, and to compensate for the shortage of the amount of waste gypsum board used as a raw material, which varies depending on the region or season, by mixing general waste paper in a stable amount. It is an object of the present invention to provide a method and a manufacturing apparatus capable of manufacturing a paper material.

Further, another object of the present invention is to use the paper material produced by the above-mentioned production method and production apparatus as a bedding for animals, and when it is used as a bedding for animals (for example, livestock), it is used in a barn. The purpose of the present invention is to provide an animal bedding that can improve the working environment and can increase the methane production rate as a methane fermented product by absorbing livestock manure.

In the method for producing a paper material using the waste pulp board separation paper of the first aspect of the present invention as a raw material, the waste pulp board release paper piece is put into water to subdivide and separate the pulp adhering to the paper piece, and the paper piece is separated. The process of stirring and crushing in water to generate a pulp liquid in which water-soluble components and the like are eluted by kneading and dispersing and suspending the plant tissue in water, and plaster, easily free pulp, water-soluble components, etc. from the pulp liquid. It is characterized by including a pulp recovery step of separating water and recovering pulp, a paper material molding step of molding the pulp into a predetermined shape, and a drying step of drying the paper material at a predetermined temperature.

In the method for producing a paper material using the waste gypsum board separation paper of the second aspect of the present invention as a raw material, in the production method of the first aspect, the paper piece is preliminarily charged at 128 ° C. or higher and 163 ° C. in the underwater stirring / crushing step. It is characterized in that it is processed by heating to a temperature range of less than.

The method for producing a paper material using the waste gypsum board separation paper of the third aspect of the present invention as a raw material is the production method of the first or second aspect, in which a predetermined amount of used paper is used in the underwater stirring / crushing step. It is characterized by being mixed.

The method for producing a paper material using the waste gypsum board separation paper according to the fourth aspect of the present invention as a raw material is the production method according to any one of the first to third aspects, wherein a predetermined amount is obtained in the underwater stirring / crushing step. It is characterized by mixing with gypsum.

The method for producing a paper material using the waste gypsum board separation paper of the fifth aspect of the present invention as a raw material is the production method according to any one of the first to fourth aspects, and in the pulp recovery step, the recovered pulp is washed with water. And dehydration.

The method for producing a paper material using the waste gypsum board separation paper as a raw material according to the sixth aspect of the present invention is the production method according to any one of the first to fifth aspects, and in the paper material molding step, after molding. The water content is in the range of 50 to 80% by weight.

The method for producing a paper material using the waste gypsum board separation paper of the seventh aspect of the present invention as a raw material is the production method according to any one of the first to sixth aspects, wherein the temperature is less than 128 ° C. in the drying step. It is characterized by being dried in.

The paper material manufacturing apparatus according to the eighth aspect of the present invention includes a crushing means for crushing a waste gypsum board into a predetermined shape and size, a paper piece collecting means for separating and collecting a piece of paper from the crushed material, and the paper piece in water. An underwater stirring / crushing means for producing a pulp liquid in which water-soluble components and the like are eluted while throwing in and kneading to disperse and suspend the plant tissue in water, and gypsum, easily released pulp and water-soluble contained in the pulp liquid. It is provided with a pulp recovery means for separating and recovering pulp by separating sex components and water, a paper material molding means for molding the pulp into a predetermined shape, and a drying means for drying the paper material at a predetermined temperature. It is characterized by that.

The paper material manufacturing apparatus according to the ninth aspect of the present invention is characterized in that, in the eighth paper material manufacturing apparatus, the pulp recovery means is provided with a washing / dehydrating unit for washing and dehydrating the recovered pulp. And.

The tenth paper material of the present invention is characterized in that it is formed of a molded product or processed product having a predetermined shape, which is produced by the production method according to any one of claims 1 to 7.

The eleventh animal litter of the present invention is characterized by comprising the paper material according to the tenth aspect.

According to the method for producing a paper material according to the first aspect of the present invention, the waste gypsum board is not fired at the time of processing, so that the firing step becomes unnecessary as compared with the method of firing the waste gypsum board of the prior art. It is simplified and can be inexpensively separated from the waste gypsum board and recycled into a paper material from which the amount of gypsum adhered is minimal to zero. Further, even if the gypsum remains on the paper material, it is possible to suppress the separation and scattering of the gypsum during use, and particularly to suppress the scattering as dust. Further, the amount of gypsum adhering to the paper can be minimized to zero, and even if the gypsum remains adhered to the paper material, it does not scatter, so that it can be used for a wide range of purposes, for example, various raw materials such as recycled paper, and cushioning. Can be used safely and securely for materials. In particular, when used as an animal bedding material, gypsum and easily free pulp do not scatter and the floor surface is not sticky, so it can be used safely and securely, and it absorbs livestock manure and uses it as a raw material for methane fermentation. Can be raised.

According to the method for producing a paper material according to the second aspect of the present invention, since the paper pieces are treated in advance in the temperature range of 128 ° C. or higher and lower than 163 ° C. in the underwater stirring / crushing step, the amount of gypsum adhering to the paper pieces can be further reduced.

According to the method for producing a paper material according to the third aspect of the present invention, the amount of waste gypsum board used as a raw material may vary depending on the region or season (season), and a predetermined amount may not be secured. By mixing used paper, the target amount of paper material can be manufactured in a stable state. In addition, the manufacturing cost is reduced.

According to the method for producing a paper material according to the fourth aspect of the present invention, it is possible to produce a paper material having further improved deodorizing properties.

According to the method for producing a paper material according to the fifth aspect of the present invention, since the recovered pulp is washed with water and dehydrated in the pulp recovery step, water-soluble components and easily free pulp are efficiently and surely removed.

According to the method for producing a paper material according to the sixth aspect of the present invention, the water content after molding is in the range of 50 to 80% by weight in the paper material molding step, so that good water absorption, water retention, heat retention and Cushioning property can be obtained.

According to the method for producing a paper material according to the seventh aspect of the present invention, in the drying step, by drying at a temperature lower than 128 ° C., the dihydrate gypsum is maintained, so that pulverization can be satisfactorily prevented. In addition, a sterilizing effect can be obtained.

According to the paper material manufacturing apparatus of the paper material of the eighth aspect of the present invention, each means (device) such as crushing, separation, stirring, pressing, molding, and drying constituting the apparatus uses a general-purpose one. Therefore, the processing process (equipment) can be simplified and inexpensively constructed.

According to the paper material manufacturing apparatus for paper material according to the ninth aspect of the present invention, the pulp recovery means is provided with a washing / dehydrating section for washing and dehydrating the recovered pulp with water, so that water-soluble components and the like can be easily removed. Free pulp can be removed efficiently and reliably.

According to the paper material of the tenth aspect of the present invention, pulp can be made into a molded product or processed product having a predetermined shape to be compatible with and suitable for various uses.

According to the animal bedding according to the eleventh aspect of the present invention, when used for livestock bedding, the amount of gypsum remaining is extremely small and it is difficult to separate, so that the gypsum does not scatter. In addition, since the easily free pulp and water-soluble components generated during crushing are also separated and removed, the easily free pulp does not scatter and the floor surface of the barn does not become sticky. In addition, it can absorb livestock manure to promote methane fermentation and increase the methane production rate.

FIG. 1 shows a method for manufacturing a paper material using the waste gypsum board separation paper according to the first embodiment of the present invention as a raw material, FIG. 1A is a process block diagram, and FIG. 1B is a block diagram in which the B portion of FIG. 1A is modified. .. It is a graph which showed the measurement result of the amount of fine gypsum generated from a paper material. It is a graph which showed the measurement result of the water absorption amount and the apparent density. It is a process block diagram which showed the manufacturing method of the paper material which made from the paper piece separated from the waste gypsum board which concerns on Embodiment 2 of this invention. It is a process block diagram of the manufacturing method of the paper material using the waste gypsum board separation paper which concerns on Embodiment 3 of this invention as a raw material. It is a graph which showed the measurement result (1) of the odor level generated from the paper material manufactured by the manufacturing method of Embodiment 3 of FIG. It is a graph which showed the measurement result (2) of the odor level generated from the paper material manufactured by the manufacturing method of Embodiment 3 of FIG. It is a process block diagram which showed the manufacturing method of the paper material which made from the paper piece separated from the waste gypsum board which concerns on Embodiment 4 of this invention.

Hereinafter, with reference to the drawings, a method and apparatus for producing a paper material using the waste gypsum board separation paper according to the embodiment of the present invention as a raw material, and an animal litter will be described. However, the embodiments shown below exemplify a method and apparatus for manufacturing a paper material using waste gypsum board separation paper as a raw material and an animal bedding for embodying the technical idea of the present invention. The invention is not intended to be specific to this and is equally applicable to those of other embodiments within the scope of the claims.

[Embodiment 1]
A method and an apparatus for manufacturing a paper material using the waste gypsum board separation paper according to the first embodiment as a raw material will be described with reference to FIGS. 1 and 2. Note that FIG. 1 shows a method for manufacturing a paper material using the waste gypsum board separation paper according to the first embodiment of the present invention as a raw material, FIG. 1A is a process block diagram, and FIG. 1B is a block diagram in which the B portion of FIG. 1A is modified. , FIG. 2 is a graph showing the measurement results of the amount of fine gypsum generated from the paper material.

The method 10A for producing a paper material using the waste pulp board separation paper according to the first embodiment of the present invention includes a crushing step 12 for crushing the waste gypsum board 11 into a predetermined shape and size, and separating a piece of paper from the crushed material. A paper piece recovery step 13 to be recovered, and an underwater stirring / crushing step 14 in which the paper piece is put into water and kneaded to disperse / suspend the plant tissue in water and generate a pulp liquid in which water-soluble components and the like are eluted. Pulp recovery step 15 for separating pulp, liberated or easily liberated pulp (hereinafter referred to as easily free pulp), water-soluble components, and water from the pulp liquid to recover the pulp, and paper for forming the pulp into a predetermined shape. It includes a material forming step 16 and a drying step 17 of drying the paper material at a predetermined temperature.

Further, in the manufacturing method 10A, in the underwater stirring / crushing step 14, a piece of paper P1 treated at another waste gypsum board processing facility or the like (note that gypsum is attached to this piece of paper) is mixed or crushed. A similar paper material may be produced in the subsequent steps by carrying in and processing the paper independently without going through the step 12 and the paper piece collecting step 13. According to this method, a piece of paper that has been discarded so far can be effectively used.

When the easily free pulp is dried, it becomes fine paper fiber pieces or paper powder (hereinafter, also collectively referred to as paper powder) that is easily released or scattered from the paper material, and is also water-soluble. The sex component is an additive added in the paper manufacturing process, for example, a mineral powder (like clay) such as kaolin as a filler, or carboxymethyl cellulose (a water-soluble and a kind of thickener) in the papermaking process. Is. These dissolve and become viscous. Therefore, in the conventional paper dressing from which these water-soluble components and the like have not been removed in advance, these are dissolved by manure during use, resulting in viscosity.

Further, although not shown, the manufacturing apparatus for carrying out this manufacturing method is a means corresponding to each of the above steps 12 to 17, that is, a crushing means for crushing a waste pulp board into a predetermined shape and size, and a crushed product. Paper piece recovery means for separating and collecting paper pieces from the paper, and underwater stirring and crushing to generate a pulp liquid in which the paper pieces are put into water and kneaded to disperse and suspend the plant tissue in water and elute water-soluble components and the like. Means, pulp recovery means for separating and recovering pulp by separating plaster, easily free pulp, water-soluble components, etc. contained in pulp liquid, and water, paper material molding means for molding pulp into a predetermined shape, and paper. It is composed of a drying means for drying the material at a predetermined temperature. The pulp recovery means also includes a washing section and a dehydrating section.

According to this manufacturing method and manufacturing apparatus, the following remarkable effects are exhibited.
A. Since the waste gypsum board is not fired during processing, the process is simplified as compared to the conventional method of firing waste gypsum board, and the paper piece can be easily separated from the waste gypsum board. , Paper materials with the amount of gypsum adhered from this piece of paper to a minimum or almost zero can be easily and inexpensively recycled and manufactured.
B. Even if gypsum remains on the paper material, the separation and scattering of gypsum can be suppressed, especially the scattering of gypsum as dust can be suppressed, so safety can be ensured and a wide range of applications such as recycled paper can be used. It can be used as a raw material such as, cushioning material, gypsum, etc.
C. In particular, when used for animal dressings, easily free pulp and water-soluble components are separated and removed during the manufacturing process, so paper dust does not scatter and the floor of the barn is sticky. It is possible to suppress the state. In addition, the methane production rate can be increased by using livestock manure as a raw material for methane fermentation absorbed. In addition, mud-cleaning, stability / cushioning property, water absorption / water retention, etc. are also improved.
D. If the raw material waste gypsum board fluctuates depending on the region or season and is insufficient, general waste paper can be mixed to produce a stable amount of paper material.
Further, the manufacturing apparatus includes a crushing means, a paper piece collecting means, a steam stirring / crushing means, a pulp collecting means, a paper material forming means and a drying means, and all of these means or devices are ordinary general-purpose means (existing means). Since it is a device) and can be composed of these, it can be constructed at a lower cost than a means (device) that employs a conventional heating (dry type, steam, hot water, etc.) method.

Hereinafter, this manufacturing method and manufacturing apparatus will be described in detail, and other effects will be clarified.

(A) Waste gypsum board The waste gypsum board 11 has the same structure as the virgin gypsum board. That is, using baked gypsum (semi-water gypsum) as the main raw material, sawdust, pearlite, foam material, etc. are mixed, kneaded with water to make a paste, poured between two base papers, and hardened into a plate shape. Have. An adhesive is applied to the inner surfaces of the two base papers, and the base paper and gypsum are adhered to each other by this adhesive.

Hemihydrate gypsum material _{(CaSO 4 · 1 / 2H 2} O) absorbs water of crystallization to be hydrolyzed by heating cured, has a property to become gypsum _(CaSO 4 · _2H 2 O) .. Transition temperature between _them, CaSO 4 · _2H 2 O and CaSO ₄ · 1 / 2H ₂ O between between 128 ° C., also CaSO ₄ · 1 / 2H ₂ O and CaSO ₄ has a 163 ° C..

The two base papers consist of a front side paper and a back side paper on the back side of the board, which have the property of adhering to gypsum and not causing waviness due to the wetting and drying processes, and moreover than ordinary paper. Paper is used to increase water resistance and strength in wet conditions. In addition, each color is white, cream, blue, etc. for the front paper, and bleached pulp, high-quality waste paper, etc. are used for the paper, and high-quality waste paper, etc. is used for the back paper. ing. As the adhesive, a vinyl acetate-based adhesive made of a thermoplastic resin is generally used.

Many of the collected and carried-in waste gypsum boards are miscellaneous and their identities are unknown, so they are sorted. In particular, if there are substances that contain harmful substances, exclude them. The excluded waste gypsum board will be treated separately and properly.

(B) Waste gypsum board crushing step In this waste gypsum board crushing step 12, after weighing, confirming and removing foreign matter contamination, the waste material is first crushed into a predetermined shape and size by a shredder. The crushed pieces at this time have a predetermined length on one side, for example, a size of about 10 mm, and are crushed until the base papers on both sides and the gypsum sandwiched between them are separated. The total amount of gypsum separated by this primary crushing is, for example, less than 2 mm, and the gypsum is attached to the paper piece by an adhesive.

After the primary crushing, gypsum and a piece of paper are separated by a predetermined sieve, for example, a vibrating sieve having a 5 mm mesh, and the collected powdered gypsum is separately recycled. In this step, about 60 to 90% is recovered, and the recovered gypsum can be reused for gypsum board or used as a raw material for cement.

As the crushing means (device) used in this step, a known crushing device, for example, a board crusher or the like is used. Since these are widely present as general-purpose devices and are known, detailed description thereof will be omitted.

(C) Paper Fragment Recovery Step In this paper piece recovery step 13, the crushed material crushed in the pre-crushing step 12 is sieved to separate and classify into gypsum and paper pieces. For example, the crushed material is separated into gypsum and a piece of paper (partially attached with gypsum) by a predetermined sieve, for example, a vibrating sieve having a 5 mm mesh. If gypsum still adheres to the separated piece of paper, it is secondarily crushed with a roller-type crusher or the like to mechanically separate the attached gypsum. By this crushing, the gypsum is separated from the bonded part. The separated pieces of paper are transported to the next process, and the gypsum is treated separately.

As the separation / classification means (device) in this separation step, a known one is used. Since these are widely present as general-purpose devices and are known, detailed description thereof will be omitted.

(D) Submersible stirring / crushing step In this underwater stirring / crushing step 14, the paper piece recovered in the front paper piece collecting step and / or the paper piece P1 from another material is put into water and stirred using a stirrer such as a screw. Then, the plaster adhering to the paper piece is refined to a predetermined particle size, and the paper piece is further kneaded to disperse and suspend the plant tissue of the paper piece in water, and a pulp liquid in which water-soluble components and the like are eluted is prepared. Generate.
The finely divided gypsum particle size is in the range of 0.075 mm to 1.5 mm, and in this range, minus (-) 0.2 mm to plus (+) 0.2 mm centered on the particle size of 1.0 mm. It is preferable to set it to. That is, if this particle size exceeds 1.5 mm, even dihydrate gypsum is easily crushed by an external force during use, and when crushed, fine powder is generated, whereas fine particles of about 1 mm are used. This is because external force is hard to work during use, so it is hard to be crushed and fine powder is hard to be generated.

Further, due to the formation of the pulp liquid, the gypsum adhering to the piece of paper is made finer and easily separated. That is, when the piece of paper is separated into the pulp liquid, the paper fiber becomes loose and bent in water, and the gypsum adheres to the loose paper fiber pinpointly, in other words, the part where the gypsum can adhere is the fiber surface. At the upper pinpoint, the adhesion area becomes smaller, and as a result, the gypsum is easily peeled off and easily separated.

In this step, the piece of paper becomes fibrous, which causes the gypsum adhering to the piece of paper to be washed away. However, although the amount of gypsum that remains unwashed is extremely small, it sneaks between the fibers and is firmly fixed between the fibers by molding and drying in the subsequent process, so that separation and scattering can be suppressed. That is, since the remaining gypsum is embedded and sealed between the fibers in the state of dihydrate gypsum, which is difficult to be pulverized, by molding and drying, it is possible to prevent the gypsum from separating and scattering during use. Further, since the gypsum adhering to the surface is also difficult to be pulverized, the rate of occurrence of fine powder of gypsum is extremely low regardless of the amount of residual gypsum, for example, it can be 1% by weight or less with respect to 100% by weight of the paper material.

That is, the fines generation rate, and easily removed from the fiber by the pulp by water stirring-crushing, are removed by washing with water, 128 ° C. (gypsum CaSO 4 · _2H 2 _O and gypsum hemihydrate CaSO ₄ · 1 / 2H 2 when heated to a temperature above the transition temperature) of _O gypsum becomes gypsum hemihydrate, although acicular structure tends to separate micronized broken, whereas gypsum to adhere remaining in use Since it sometimes separates and easily scatters, the remaining gypsum is less likely to scatter by soaking it in water and changing it to dihydrate gypsum without raising it to a temperature that exceeds this transition temperature. After disintegrating, the three-dimensional shape holds most of the remaining gypsum inside, which makes it difficult to scatter and is achievable.

When paper is crushed by a dry method as in the prior art, uneven crushing is likely to occur because it is light, and a large amount of paper dust composed of fine paper fibers is generated. However, when the paper is stirred and crushed in water as in the present embodiment, In addition to being able to crush evenly due to the resistance of the water flow, it is difficult for paper dust to be generated, and since water-soluble components contained in the paper can be eluted, these can be separated from the pulp in the next process. ..

As the underwater stirring / crushing means (device) used in this step, a known one is used. Many of these are present as general-purpose mounting means (devices) and are known, so detailed description thereof will be omitted. As the preheating means (device) described later, a known one is used.

The underwater stirring / crushing step may be changed as follows. That is, although the paper piece (including P1) was treated without heating, it may be treated by preheating. That is, the separated pieces of paper are heated to a predetermined temperature, for example, a temperature range of 128 ° C. or higher and lower than 163 ° C., and then stirred in water to form pulp. This allows less gypsum to remain. The temperature range of 128 ° C. or higher and lower than 163 ° C. is preferably 128 to 162 ° C. from the viewpoint of safety.
In addition, this preheating is performed by the preheating means (apparatus) before or after the agitation / crushing step in water.

In this case, the remaining gypsum absorbs water and becomes dihydrate gypsum again, so that it can be suppressed from being pulverized and scattered during use. If it is heated at a temperature exceeding 163 ° C (transition temperature between hemihydrate gypsum and anhydrous gypsum), it becomes anhydrous gypsum, and even if water is applied again, it does not become dihydrate gypsum. Therefore, heating above 163 ° C is recommended. It doesn't become. Further, a high water pressure water washing machine may be used instead of the screw stirring device. By using this high water pressure water washing machine, the amount of gypsum adhering to a piece of paper can be reduced to almost zero. A high water pressure water washing machine is already known, and this is used. Further, in this step, other materials such as used paper may be mixed. Further, a surfactant may be mixed. By mixing this surfactant, the amount of water absorption can be increased when it is used as a litter. This mixing is selectively performed depending on the use of the paper material.

The term "pulp liquid" is a liquid in which paper fibers (plant fibers) are suspended in water, "pulp" is a plant fiber mainly made from wood, and easily free pulp has already been mentioned above. The details will be described later.

(E) Pulp recovery step In this pulp recovery step, the pulp liquid is screened using a sieving device (also called a screen) to remove gypsum, separate and separate pulp pieces, and the pulp is recovered. .. Further, in this step, it is preferable to add a washing and dehydrating part (means / apparatus, not shown) and wash and dehydrate the recovered pulp with water to remove water-soluble components and the like remaining in the fiber and easily free pulp. As a result, the gypsum remaining in the fibers is contained in the paper material by molding in the next step, and the water-soluble components and the easily free pulp are squeezed out by dehydration. Further, by repeating this washing with water and dehydration several times as necessary, 90% or more or almost all of the water-soluble components and easily free pulp are removed.

The "dehydration" in this step is dehydration in which the recovered pulp is washed with water and dehydrated to efficiently remove water-soluble components and easily free pulp contained in the recovered pulp, and the water content after molding in the next step. Is different from the one that adjusts.

In the sieving device, the mesh is preferably in the range of 1.5 to 2 mm. This is because if it is within this range and less than 1.5 mm, easily free pulp remains, and if it exceeds 2 mm, useful paper pulp is removed. In addition, the reason why the floor surface becomes sticky when used as a litter is that the water-soluble components contained in the paper gradually dissolve and become viscous, and at the same time, they scatter and accumulate, or the fine fiber powder that is kicked by animals and scattered. This is because the paper dust made of the above is mixed with the paper dust to promote this sticky feeling, and by separating and removing these in this step, it is possible to suppress or prevent the floor surface from becoming sticky. In addition, since easily free pulp of other causes is also removed, it is possible to suppress or prevent it from scattering during use and also becoming sticky.

The pulp in the pulp liquid (hereinafter also referred to as waste paper pulp because it is a kind of waste paper pulp) is different from new pulp (virgin pulp) made from wood, so these are added below. To do.
That is, the latter virgin pulp has many folds on the surface of the fibers, so that the fibers are entangled with each other and has strength, and since there are no cracks in the cross section of the fibers, each fiber is strong and firm. On the other hand, the latter waste paper pulp is rubbed and folds are worn down every time it is regenerated, so that the fibers are not easily entangled with each other, which reduces the strength, and the fibers are cracked inside and the fibers are fragile. ..

Then, since the pulp liquid is mixed in the state of the waste paper pulp, it is difficult for the individual pulps to form an aggregate thereof due to the weak entanglement of the fibers, and on the other hand, the aggregated fibers Some of them are very entangled even if they are minute, and some are trapped between the strongly entwined fibers.
Therefore, when this pulp liquid tries to pass through a predetermined mesh size (1.5 to 2 mm), those with weak fiber entanglement are immediately passed and removed, and aggregates exceeding the mesh size should not pass through. become. Therefore, this sieving is not the size or length of the pulp fibers, but the pulp (easily released pulp) in which the fibers are weakly entangled and is already released or easily released is separated and removed. Easy-to-free pulp causes mudification (sticky state).

The means for carrying out this pulp recovery step comprises sieving means, washing and dehydrating (for example, squeezing) means (equipment), etc., all of which are already known and are used.

(F) Paper material molding step In this paper material molding step 16, the pulp recovered in the previous step is molded into a shape suitable for and suitable for each application. That is, the recovered pulp is made into a molded product or a processed product having a predetermined shape to be compatible with and suitable for various uses. The shape thereof is not limited to a specific shape, but may be an arbitrary shape such as a block shape, a sheet shape, a pellet shape or a flake shape. Further, for the litter, it is preferable to mold it into a predetermined shape and adjust the water content after molding to a predetermined value.

By this step, most of the gypsum remaining on the piece of paper is embedded in the molded body at the time of molding, and the amount exposed on the surface of the molded body is further reduced. As a result, the gypsum embedded in the molded body can be prevented from scattering to the outside. That is, since the remaining gypsum is embedded and sealed between the pulp fibers in the state of dihydrate gypsum, which is difficult to be pulverized, by molding and drying, it is possible to prevent the gypsum from separating and scattering during use. Further, since the gypsum adhering to the surface is also difficult to be pulverized, the rate of occurrence of fine powder of gypsum can be extremely low regardless of the amount of residual gypsum. As a result, it becomes a recycled paper material in which the residual gypsum is prevented from being pulverized and scattered.

That is, in the above-mentioned shape, for example, when it is made into a spherical shape, the surface area is minimized, and most of the residual gypsum exists in a state of being attached to the paper fibers inside the paper and is blocked from the outside, so that it is separated. It is possible to suppress the scattering to the outside.
Further, after forming a spherical body, it can be crushed into a flat plate to form a flat plate in which most of the remaining gypsum is fixed inside. In addition to the spherical body, the shape that minimizes the surface area includes, for example, a mass (object) body having at least one surface flat or curved. Further, by reducing the apparent surface area, more residual gypsum can be fixed inside, and a deodorizing effect is exhibited.
In addition, a flat plate with a large amount of residual gypsum can be produced by shaping it into a spherical shape and then crushing it into a flat plate.

What is important here is that the incidence of fine gypsum that separates and scatters gypsum from the paper material during use has decreased regardless of the amount of remaining gypsum. The generation rate of this fine gypsum is preferably 1% by weight or less with respect to 100% by weight of the paper material.

Further, for the litter, it is preferable to form a predetermined shape and adjust the water content after molding in the range of 50 to 80% by weight.
That is, a water-retaining space can be formed inside the piece of paper by molding the piece of paper crushed into a fibrous form. Further, better water absorption, water retention, heat retention and cushioning can be obtained by molding while adjusting the water content after molding. At this time, if the paper fibers are compressed (squeezed) too much during molding, the once crushed paper fibers are compressed, the space between the paper fibers is narrowed, and the water absorption, water retention, heat retention and cushioning properties are impaired. On the other hand, if the compression is weak, the space between the paper fibers becomes too wide and the weight of the retained water exceeds the surface tension, and the once absorbed moisture easily flows out, and the shape is maintained between the molding process and the drying process. Will disappear.

The degree of this compression can be evaluated by the water content after molding, and preferably, by molding with the water content after molding at 50 to 80% by weight, an appropriate space is created between the paper fibers after drying, and excellent water absorption is achieved. , Water retention, heat retention and cushioning can be obtained. This point will be described in detail in Table 2, FIG. 3 and its description described later.

Further, when a piece of paper crushed into a fibrous form is formed, a water retention space can be formed inside the piece of paper. That is, when used as a litter for animals, if the paper fibers are laid on the floor of the barn alone or in a stacked state, a large amount of water is stored around the paper fibers and between the paper fibers, so that the paper fibers are crushed by a dry method. Like a piece of paper, the water retained is dispersed due to the movement of animals, etc. However, by molding, most of the water can be stored inside, so the dispersion of water can be prevented.

For this reason, when absorbing manure with a high water content such as dairy cows, the solid content of the manure adheres to the surface, but since the water is stored inside the litter, the solid content dries quickly and additional manure is attached. However, since the water is immediately transferred to the inside, the solid content of manure does not disperse in a sticky state. On the other hand, since the solid content and water of manure adhere to the surface of the paper piece crushed by the dry method, the solid content dries slowly and is widely dispersed on the floor surface due to the movement of the litter.

Since the surface becomes denser than the inside by molding or squeezing with a mold, it is difficult for the water to flow out from the surface even if the amount of water retained inside increases. On the other hand, even if the paper litter that maintains the same paper shape is kneaded or fluffed to improve water absorption and water retention, most of the water-retaining part has a structure that spreads outward, which is the true meaning. Poor water retention.

As a means for executing the paper material forming step 16, a forming machine for forming into a block shape, a sheet shape, a pellet shape or a spherical shape is used, and a pressing and dehydrating means (device) also uses a pressing machine. These are already known and are used in this embodiment.

This paper material molding process may also be modified as follows.
First, in this embodiment, the molded product is formed into a sheet shape, a pellet shape, a flake shape, or the like in the paper material molding step, but the molded product molded in this paper material molding step is dried in the next drying step and then cut or the like. , A processed product (paper piece) having a predetermined shape or size may be used. For example, a sheet-like material is cut into a paper material having a predetermined shape and size. As a result, for example, when making a mold, a mold is required for each different dimension, but when cutting later, it is not necessary to make each mold, and the cost is reduced.

Further, instead of this paper material forming step, it may be replaced with another pressing / crushing step. That is, instead of the paper material forming step 16 replaces the pressing-crushing step 16A, the process and dewatering (squeezing) 16 ₁ pulp recovered in pulp recovery process 15 is dehydrated (squeezing), and then disintegrated solution constituting between砕部16 ₂ (see FIG. 1B). This change has the following advantages. For example, when it is used as a dressing, it is squeezed and dehydrated and then crushed to an appropriate size to make the size and shape different, and it can be spread at appropriate intervals, and a part of the peripheral edge protrudes. Therefore, it is possible to prevent the litter from interfering with each other and being scattered by the movement of animals to form spots.

(G) Drying Step In this drying step 17, the molded product or molded product molded in the previous step is dried by heating and / or blowing air at a temperature lower than 128 ° C. (transition temperature between dihydrate gypsum and hemihydrate gypsum). What is important in this step is that when heated at 128 ° C. or higher, the dihydrate gypsum becomes semi-hydraulic gypsum and is easily pulverized, so that it is dried at less than 128 ° C. That is, when it is dried at a temperature lower than 128 ° C., the dihydrate gypsum is maintained, so that pulverization can be satisfactorily prevented. Further, when it is dried in the range of 100 ° C. to 127 ° C., a sterilizing effect can be obtained.

Further, it may be dried by natural drying instead of heat drying. This simplifies the drying equipment and eliminates the need for fuel.
The moisture content of the paper material after drying is 20% or less to ensure water absorption and prevent the formation of mold, and 5% or more (hardens) to provide cushioning properties, preferably in the range of 8 to 15%. is there.

The drying means (device) used in this step is composed of heating and / or blowing air, all of which are already known and are used.

(H) Paper material The paper material 18 is manufactured by the above steps or devices. Since the manufactured paper material 18 exhibits the excellent adoption effect already described in each process, it can be safely and safely used for a wide range of applications such as various raw materials such as recycled paper, cushioning materials and litters.

Although not shown, the manufacturing apparatus for carrying out this manufacturing method is a means corresponding to each of the above steps 12 to 17, that is, a crushing means for crushing a waste plaster board into a predetermined shape or size, and a piece of paper from the crushed material. A means for collecting a piece of paper that separates and recovers a piece of paper, and a means for stirring and crushing a piece of paper that is kneaded into water to disperse and suspend the plant tissue in water and generate a pulp liquid in which water-soluble components and the like are eluted. , Pulp recovery means for separating and recovering pulp by separating plaster, easily free pulp, water-soluble components, etc. and water contained in pulp liquid, paper material molding means for molding pulp into a predetermined shape, and paper material. It is composed of a drying means for drying at a predetermined temperature. The pulp recovery means also includes a washing section and a dehydrating section.

All of these means or devices are ordinary general-purpose means (devices), and since they can be configured by these means (devices), they are compared with the means (devices) that employ the conventional heating (dry type, steam, hot water, etc.) method. It can be constructed inexpensively.

(I) Use for bedding When this paper material 18 is used for bedding for livestock and the like, the following remarkable effects are exhibited.

First, the paper material is made into a litter with a shape and size that matches livestock.
That is, the shape and size differ depending on the target animal, but in the case of livestock, etc., it is not a single shape and the size is not a single size, but a maximum of about 20 mm centered on about 5 to 10 mm, and it should not move much due to the movement of the animal. Slightly flat and slightly protruding limbs. That is, the state of being squeezed and crushed is preferable.

When a predetermined amount of such a litter is laid on the floor of the livestock barn, the paper dust consisting of gypsum and fine fibers remaining on the paper material during the laying does not scatter as dust. In addition, when livestock manure is absorbed, it becomes a raw material for methane fermentation, and the methane production rate can be increased. Further, since the amount of gypsum adhered to the paper material used for the litter is extremely small to almost zero, it does not adversely affect livestock. Even if gypsum remains, the amount is extremely small, and it is a dihydrate gypsum that is difficult to pulverize, and most of it exists in a state of being attached to the paper fibers inside the paper and is shielded from the outside. Therefore, it does not separate or scatter.

Further, since the paper material is made in the form of pulp, a gap is formed between the paper fibers, and this space becomes a water retention space, which enhances water absorption and also increases the diffusion rate. In addition, the contact area with air increases, and evaporation is promoted. In addition, the water in the manure that comes in contact with the paper is absorbed by the paper and quickly diffuses along the fibers.

Further, when the amount of manure is relatively small, the diffused water has a large contact area with air, so that the evaporation rate of odorous components such as ammonia in the water becomes high. However, because the total amount is small, it diffuses and dilutes before it reaches the problematic odor level. On the other hand, if the amount of manure is relatively large, it is stored inside the shaped paper. In this case, the contact area between the moisture and air inside is reduced, and the evaporation rate of odorous components such as ammonia is also slowed down. As a result, the amount of odorous components released into the atmosphere in a short time is suppressed, and the odor level does not increase.

It should be noted that paper that retains its paper shape, such as by crushing conventional paper in a dry manner, stores a large amount of water on its surface, resulting in a large contact area with air, a high evaporation rate, and moisture retention. It becomes easy to scatter. For this reason, especially when collecting the litter containing manure, a large amount of water flows out, which deteriorates the workability of the collection work and also causes odor components (mainly ammonia components) in the water that have flowed out or scattered. Dissipates at once and deteriorates the environment inside the barn.
In particular, when collecting the litter containing manure, the water retained in the water flows out or scatters, increasing the contact area with the air at once, and the water on the surface splashes, volatilizing odorous components such as ammonia. , Deteriorate the working environment. On the other hand, this paper material does not rapidly increase the contact area with air even if it is agitated, and it is difficult for it to splash, so the volatilization of odorous components such as ammonia does not increase, and the working environment deteriorates. do not do.

Further, by forming the fibrous crushed paper piece, a water retention space can be formed inside the paper piece. Further, better water absorption, water retention, heat retention and cushioning can be obtained by molding while adjusting the water content after molding.

Furthermore, in the pulp recovery process, the easily free pulp and water-soluble components, which absorb water during use and cause the floor surface of the barn to become sticky, are separated and removed, so that the easily free pulp dries. Paper dust made of fine fibers does not scatter, and the floor surface is less likely to become sticky. Furthermore, since it is agitated and crushed in water, the paper fibers are entangled during molding and have sufficient shape retention, so there is no need to use a binder, etc., and the floor surface becomes sticky due to the dissolution of the binder. Alternatively, it does not cause a decrease in water absorption.

If paper, including used paper, is used as the litter, muddying may become a problem. The following is a note about this mud-cleaning.
The cause of this mudification, or viscosity, is mainly due to the viscosity derived from paper, the viscosity derived from manure, and the synergistic action of both.

A) Viscous properties derived from paper a) Water-soluble components, etc. Paper has various additives in the manufacturing process, and one of them is mineral powder such as kaolin (similar to clay) added as a filler. It is fixed between the paper fibers by an adhesive. Generally, this adhesive is insoluble in water, but when the paper absorbs water, the paper fibers swell, the adhesive strength weakens, the paper fibers are dissociated, and mineral powder such as kaolin also dissolves, causing viscosity. Conceivable. In addition, carboxymethyl cellulose and the like may also be used in the papermaking process, and these are water-soluble thickeners and can cause viscosity.

Therefore, in the conventional paper dressing in which these water-soluble components and the like are not removed in advance, these water-soluble components and the like are dissolved by manure during use. The dissolution of the water-soluble component and the like was confirmed in Examples 22 to 24 described later.
Strictly speaking, mineral powders such as kaolin are not water-soluble components, but macroscopically they dissolve and suspend, so these are collectively referred to as water-soluble components and the like.

b) Easy-to-free pulp paper is reinforced with an adhesive because the fiber length is relatively short and the bonding by entanglement of fibers is weak. This adhesive is not water-soluble, but when the paper absorbs moisture and swells, its adhesive strength weakens and it becomes easy to loosen. In particular, conventional paper beddings such as dry crushing and fiber kneading tend to disintegrate when they contain water (particularly in the torn portion of the peripheral edge), and easily released pulp is generated. Furthermore, it is considered that more easily free pulp is generated and remains in the dry crushing method. It is considered that the easily free pulp is easier to dissolve water-soluble components and the like than the paper bedding itself.

c) Surface tension Since paper litter and easily free pulp have a large contact area through moisture with respect to their own size (weight), the adsorption force due to surface tension is strong, especially when it becomes minute like easily free pulp. The resistance during movement (misalignment) becomes felt as viscosity.

B. Viscosity derived from manure Manure such as cattle is originally viscous.

C. Synergistic action of both Paper stores a lot of water on the surface. Therefore, manure also adheres to the surface and between the litter in a wet state. Therefore, when there is no movement (displacement) between the litters, the solid content of manure aggregates and adheres to the paper surface while wet, but when the movement (displacement) occurs, the concentrated solid content flows out. Therefore, the floor surface becomes sticky.

At present, sawdust is generally used for litter, which absorbs livestock manure and methane fermentation is performed using this as a raw material, but there is a problem that methane production efficiency cannot be improved by this. However, by using the paper material of the present embodiment as a litter, the methane production efficiency can be increased.

From the above, by using the paper material of the present embodiment as a litter, it is possible to provide a litter that is cheaper and easier to use than the current sawdust, and by using manure mixed with this litter, methane fermentation can be performed. The efficiency of methane generation can be improved. In addition, since the supply and demand of sawdust is currently tight, it can be used as a substitute for them.

<Experiment on fine powder generation rate (Experimental Examples 1 and 2)>
The action and effect of the paper material produced by the production method of the first embodiment were confirmed by Experimental Examples 1 and 2.

First, the waste gypsum board is crushed, and the one with a side of 5 mm or more is separated as paper. Water is added to the paper piece to which the gypsum is attached, and the paper is stirred and dissociated with a screw, and then filtered with a wire net having an opening width of 2 mm. The obtained pulp was further rinsed with water to remove gypsum and the like, placed in a mold, molded, and dried at 110 ° C.

Next, the dried paper material was cut to prepare a paper material having a side of 10 mm square as a sample of Experimental Example 1. The paper material of Experimental Example 1 is placed in a container, shaken with a shaking tester, and sieved with a 200 mesh sieve a total of 3 times every hour (3 hours in total), and the weight of the components on the sieve and the components passing through the sieve. The weight of the generated gypsum fine powder was measured by measuring the weight of each of the above.

Similarly, a piece of paper before the washing treatment was heated at 150 ° C. for 2 hours, and then sieved with a 200 mesh sieve as a comparative sample of Experimental Example 2. The comparative sample of Experimental Example 2 was shaken in the same manner as in the case of Experimental Example 1, and the weight of the generated fine gypsum powder was measured. The results shown in Table 1 and FIG. 2 were obtained from these measurements. The fine powder generation rate in the shaking test shown in Table 1 and FIG. 2 is an alternative value to the rate at which the gypsum adhering to the paper material becomes fine powder when the paper material is used as a litter, for example, and is stepped on by a cow or the like. Corresponds to.

From the results shown in Table 1 and FIG. 2, the following was found. That is, as shown by the solid line in FIG. 2, the paper material of Experimental Example 1 was started to be used before the experiment (for example, before the paper material was used for the litter), and a total of 3 times (within 3 hours) every hour. The incidence of fine powder (gypsum) changed from about 0.3% to 0.2%, 0.1%, and 0.2% at the beginning, and all the values were 0.3% or less at the beginning. On the other hand, in the paper material of the comparative sample of Experimental Example 2, as shown by the dotted line in FIG. 2, the fine powder generation rate starts from 0.5%, and is 1.1%, 0.9%, 0.7. It has changed to%, and the highest value has reached 1.1%. In addition, these values show the occurrence rate of fine powder (gypsum) during use of a paper material.

From this result, the paper material of Experimental Example 1 corresponding to the present embodiment has a smaller generation rate of fine powder (gypsum) during use than the paper material of the comparative sample corresponding to the prior art, so that it is safe and secure. You will be able to use it. In particular, it can be seen that when used as a litter as described above, it exerts a remarkable effect.

<Experiment on water content after molding (Experimental Examples 3 to 9)>
Next, the water content after molding, the water absorption after drying, the cushioning property, and the shape retention between the molding step and the drying step of the paper piece produced by the manufacturing method of this embodiment were confirmed by Experimental Examples 3 to 9. did.

First, the waste gypsum board separation paper was stirred and crushed in water, and then the pulp obtained by filtering with a wire mesh having an opening width of 2 mm was further rinsed with water to remove gypsum and the like, and then placed in a mold for molding. At the time of molding, the water content after molding was changed in the range of about 40 to 90% by weight, and then dried at 100 ° C. to obtain samples of Experimental Examples 3 to 9. Next, the water content, apparent density and weight of the samples of Experimental Examples 1 to 7 after drying were measured. After that, after sufficiently absorbing water, the excess water adhering to the surroundings was wiped off, the weight was measured, and the amount of water absorption was calculated. In addition, the elasticity (cushioning property) of each sample and the shape retention property between the molding process and the drying process were also confirmed. The results are shown in Table 2 and FIG.

From the results shown in Table 2 and FIG. 3, the following was found.
As the water content after molding increased, the apparent density decreased, while the water absorption increased. This is because as the water content after molding increases (the degree of compression during molding decreases), the internal space (that is, the water retention space) of the paper piece becomes wider, the apparent density decreases, and the amount of water absorption increases. It was found that when the water content after molding was 50% by weight or more, the water absorption amount was 1 times or more the weight before water absorption, and the performance as a litter was obtained.

Regarding the cushioning property, when the water content after molding was about 40% by weight, the cushioning property was not recognized because the internal space was narrow, but when it was 50% by weight or more, the cushioning property could be confirmed to some extent, and when it was 90% by weight. I felt quite a bit. It should be noted that the cushioning property when actually used as a litter is not only the elasticity of a single litter, but is obtained by overlapping litters, so if there is some elasticity, there is no problem in use and the cushioning property can be obtained. I also confirmed.

Further, in the handling from molding to drying, there was no particular problem when the water content after molding was about 80% by weight, but when it was close to 90% by weight, the shape could not be maintained and the product was deformed.
From the above results, it was found that by controlling the water content after molding within 50 to 80% by weight, a litter that can be molded and has excellent water absorption, water retention and cushioning properties can be obtained.

[Embodiment 2]
A method and an apparatus for producing a paper material using the waste gypsum board separation paper according to the second embodiment of the present invention as a raw material will be described with reference to FIG. FIG. 4 is a process block diagram of a method for manufacturing a paper material using the waste gypsum board separation paper according to the second embodiment of the present invention as a raw material. Although this manufacturing method also has a pressing / crushing step 16A (FIG. 1B), it is omitted.

By the way, in the manufacturing method (device) of the first embodiment, the discharge amount of the waste gypsum board as a raw material varies depending on the region or the season (time), and there is a possibility that the predetermined amount cannot be secured. In that case, the manufacturing method (device) of the first embodiment cannot manufacture the target amount of paper material in a stable state. Therefore, in the manufacturing method (device) of the first embodiment, it is possible to manufacture the paper in a stable state in which the target amount of paper material can be secured by further mixing the used paper.

The production method 10B of the second embodiment is obtained by further mixing a predetermined amount of used paper in the production method 10A of the first embodiment, that is, in the underwater stirring / crushing step 14 of the production method 10A, a predetermined amount of the used paper or the surface activity. The difference is that the agent is mixed, and the other steps are the same. Therefore, in the following description, the common steps are designated by the same reference numerals and the explanations are used to describe the different steps in detail.

The manufacturing method 10B of the second embodiment has a configuration in which a predetermined amount of general waste paper P2 is further mixed in the manufacturing method 10A of the first embodiment.
The type of used paper P2 to be mixed is not limited to a specific one, and is general used paper such as newspapers, magazines, copy papers, and corrugated cardboard. Since these used papers also have their own characteristics, for example, in the case of used papers that have been waterproofed, it is preferable to further add a surfactant to improve the wettability. That is, by adding the surfactant to water, the surfactant can act even in the kneaded paper fibers, and hydrophilicity can be imparted to the entire paper fibers.

The amount of used paper P2 to be mixed is set to an amount that compensates for the shortage of waste gypsum board separation paper in the production method 10A of the first embodiment when the target amount of paper material cannot be secured.
That is, the amount of this mixture is appropriately determined by the amount of paper material produced by the production method 10A of the first embodiment.

The ratio of the waste gypsum board separation paper and the general waste paper in the production method 10A of the first embodiment may be any of 50%: 50%, 70%: 30%, 30%: 70%, and the like, and is particularly limited to a specific ratio. It does not have to be anything but may be arbitrary. The used paper may be 100%.

Further, in the case of mixing, it is preferable to cut and crush the used paper into a predetermined shape and size in advance with a crusher or the like, and mix the cut and crushed paper pieces. As a result, the processing time in the underwater stirring / crushing step 14 is shortened and the processing efficiency is improved. Further, a surfactant (already known) may be further mixed. The mixture of the surfactant is a case where the waterproof paper is mixed or a case where it cannot be specified that the waterproof paper is not mixed, and the amount thereof varies depending on the type of the surfactant, but should be several% or less.

As the manufacturing apparatus that executes the manufacturing method 10B of the second embodiment, the manufacturing apparatus of the first embodiment can be used as it is. In addition, a machine for cutting and processing general used paper is also known, and this is used.
According to the manufacturing method (device) of the second embodiment, the same action and effect as the manufacturing method (device) of the first embodiment are obtained, and further, the target amount of paper material is manufactured by the manufacturing method (device) of the first embodiment. You can avoid being unable to do so.

That is, when the used paper is mixed, easily free pulp and water-soluble components can be removed, and the waterproofed used paper is also kneaded by adding a surfactant to the water in the underwater stirring / crushing process. In addition to being able to impart hydrophilicity to the entire unraveled paper fiber, most of the molded bedding has paper fibers inside the bedding, so water can be retained inside the bedding, so it is considered as a waste paper with water absorption. Similarly, since it can be mixed with the waste gypsum board separation paper piece, any amount of used paper can be mixed regardless of the type. Therefore, stable production is possible regardless of the region and season.

<Experiment on mixing used paper and water absorption (Experimental Examples 10 to 21)>
An animal bedding was prepared using the paper material produced by the production method of the second embodiment, and the amount of water absorption was confirmed.
First, water droplets were dropped onto a piece of waste gypsum board separation paper, two types of used copy papers 1 and 2, used corrugated cardboard, and a used parking ticket, and water absorption was confirmed.

As a result, in the waste gypsum board separated paper piece, the dropped water droplets permeated the paper and diffused. Further, in the used copy paper 1, the dropped water droplets permeated the paper and diffused. Further, in the used copy paper 2, the dropped water droplets did not permeate so much, stayed on the paper surface, and did not diffuse. Further, in the used corrugated cardboard, the dropped water droplets did not permeate the surface of the paper and stayed on the paper surface and did not diffuse, but when the cross section where the paper was torn and the polar surface layer were peeled off, the used corrugated cardboard permeated and diffused. On the other hand, the used parking ticket had a contact angle with the dropped water droplets exceeding 90 ° and showed water repellency, and the torn portion also showed water repellency.

Next, the water absorption of the paper material produced by the production method of the second embodiment using the waste gypsum board separation paper piece and other used paper as raw materials was measured.
That is, a mixture of waste gypsum board separation paper pieces, used copy papers 1 and 2, used corrugated cardboard, used parking tickets, and waste gypsum board separation paper pieces at a weight ratio of 1: 1. After adding water and stirring and disintegrating with a screw, the pulp obtained by filtering with a wire net having an opening width of 1.5 mm is further rinsed with water to remove gypsum, easily free pulp, water-soluble components, etc., and then molded into a mold. It was put and molded and dried at 110 ° C. to prepare samples of Experimental Examples 10 to 15 having a diameter of 3 mm and a thickness of 4 mm. Further, in the crushing step, samples of Experimental Examples 16 to 21 were prepared in the same manner except that a surfactant was added to water.

From the results shown in Table 3, the following was found. The sample of Experimental Example 10 using the waste gypsum board separation paper piece as a raw material had a sufficient water absorption. In addition, the sample of Experimental Example 11 using the used copy paper 1 having water absorption as a raw material also had a sufficient amount of water absorption. Further, the sample of Experimental Example 12 using the used copy paper 2 having poor water absorption as a raw material was slightly inferior to the sample of Experimental Example 10, but had a sufficient amount of water absorption. In addition, the surface of the sample of Experimental Example 13 made from corrugated cardboard is waterproofed, but it is only the polar surface, and there are many parts that are not waterproofed, so the amount of water absorption is sufficient. there were. On the other hand, the sample of Experimental Example 14 using a used parking ticket having water repellency as a raw material hardly absorbed water. Further, the sample of Experimental Example 15 prepared by mixing the waste gypsum board separation paper piece and the used parking ticket had about half the water absorption of the sample of Experiment Example 10 using the waste gypsum board separation paper piece as a raw material.

As a result of measuring the water absorption amount in the same manner for the samples of Experimental Examples 16 to 21 to which the surfactant was added, the water absorption amount was larger in all the samples to which the surfactant was added. In particular, the sample of Experimental Example 20 using a used parking ticket as a raw material, which hardly absorbed water in the sample to which no surfactant was added, and a waste gypsum board separation paper piece and a used parking ticket were mixed at a weight ratio of 1: 1. The sample of Experimental Example 21 prepared as described above had a larger amount of water absorption than the samples of other Experimental Examples 16 to 19.
From the results of Experimental Examples 10 to 21, the water absorption of the waste gypsum board separation paper piece or the animal litter made from general waste paper does not change, and the surfactant is added even to the waste paper that has been waterproofed. It was found that the same or higher water absorption can be obtained.

An aqueous phase was visually confirmed on the surface of all the samples to which the surfactant was added, whereas the surface of the sample to which the surfactant was not added was wet, but the aqueous phase was observed. Could hardly be confirmed. This indicates that the addition of the surfactant makes it easier for water to adhere to the surface, and as a result, the amount of water absorption increases. Although this increases the amount of water absorbed, the water content of manure retained on the surface is dispersed as the animal moves, and the odor is easily diffused.

Therefore, even if the waterproof waste paper is cut and sprayed with a surfactant as in the prior art, water can be retained only on the surface thereof, which deteriorates the environment of the livestock barn, whereas the manufacturing method of the second embodiment is used. Even if a surfactant is added to the prepared litter, a large amount of water in manure can be retained inside the litter, so that the environment of the barn does not deteriorate even with waterproof waste paper.

<Experiment on stickiness (elution of water-soluble components, etc.) (Experimental Examples 22 to 24)>
Using the used paper (used copy paper 1) used in Experimental Example 11, an experiment was conducted on the cause of the sticky floor surface, which is a problem with conventional paper dressings.
A piece of paper obtained by cutting the used copy paper 1 into a square of about 10 mm (Experimental Example 22), a piece of paper cut into a square of about 10 mm and then kneaded with a finger (Experimental Example 23), and a piece of paper prepared by the manufacturing method of the second embodiment (Experimental Example 23). Each of Experimental Examples 24) was placed on a petri dish, water was dropped with a dropper so that the whole was sufficiently wet, and then the mixture was allowed to stand. After 30 minutes and 1 hour, the condition was visually confirmed and the surface condition was rubbed with a finger. It was confirmed. The results are shown in Table 4.

From the results in Table 4, the following was found. The piece of paper that was just cut (Experimental Example 22) showed almost no change visually even after 1 hour, but when rubbed with a finger, the surface peeled off even after 30 minutes and fine fibers were generated, and after 1 hour, it was light. The surface began to peel off even when rubbed, and I felt a little slimy. In addition, the surface of the piece of paper that was cut and kneaded (Experimental Example 23) became slightly fluffy after 30 minutes, and when rubbed with a finger, it was easily peeled off to generate fine fibers and a slight sliminess was felt. It was. After 1 hour, it became more swelled, and when rubbed with a finger, the surface was easily peeled off, and when rubbed further, it was torn and slimy was felt. On the other hand, the piece of paper (Experimental Example 24) produced by the manufacturing method of the second embodiment does not change visually, the surface does not peel off even if it is rubbed with a finger, and fine fibers are not generated. However, fine fibers were not generated.

From this, it was clarified that when the used paper absorbs water, the fine fiber powder becomes soggy and easily peels off from the surface, and the water-soluble components that are the source of sliminess dissolve out, resulting in a sticky state. In particular, it is further promoted by kneading or crushing the used paper to facilitate the separation of the paper fibers, whereas the paper piece produced by the manufacturing method of the second embodiment has the paper fibers removed from the surface even if it absorbs water. It was found that these did not cause a sticky state because they did not separate and did not become slimy.

Various chemicals are added to paper (including used paper) in the manufacturing process. In particular, kaolin (clay component) is used as a filler to fill the gaps in the paper, and carboxymethyl cellulose is used as a thickener. Etc. may be added, and it is considered that these water-soluble components and the like dissolve and develop viscosity.

In the prior art, the water absorption is enhanced by kneading the paper, and the water absorption and the separation of the paper dust and the dissolution of the water-soluble components (resulting in a sticky state) conflict with each other. Also turned out.

<Experiment on dressing (Experimental Example 25)>
In Experimental Example 25, an animal litter was prepared using a paper material produced by the same production method as in the second embodiment, and the degree of scattering of gypsum and paper dust was confirmed. That is, a waste gypsum board is crushed, and a piece of paper having a side of 5 mm or more is separated as paper, and corrugated cardboard is mixed with a piece of paper to which gypsum is attached at a ratio of 20% by weight, water is added, and pulp is passed through a crusher. After crushing in water until it became a shape, it was squeezed and dehydrated by a screw press dehydrator having an opening width of 2 mm. After that, it was washed with water, squeezed and dehydrated again with a screw press dehydrator so that the water content became 50 to 80% by weight, and then crushed into a mass mainly of 5 to 10 mm with a crusher equipped with a stirrer. Then, an air was blown to the agglomerated paper material, and the air was dried to obtain a litter. This paper material was spread in the barn as a litter. There was no scattering of gypsum or paper dust during the laying work, and the floor surface did not become sticky even during use. In addition, when the litter containing manure was collected, no water flowed out and no strong odor was generated.

Next, a method and an apparatus for manufacturing a paper material using the waste gypsum board separation paper according to the third embodiment of the present invention as a raw material will be described with reference to FIGS. 5 to 7. 5 is a process block diagram of a method for producing a paper material using waste gypsum board separation paper according to the third embodiment of the present invention as a raw material, and FIG. 6 is an odor level generated from the paper material produced by the production method of FIG. The measurement result (1) is shown in a graph, and FIG. 7 is a graph showing the measurement result (2) of the odor level generated from the paper material manufactured by the manufacturing method of FIG.

The production method 10C of the third embodiment is different in the production method of the first embodiment in that a charcoal mixing step is interposed between the underwater stirring / crushing step and the pulp recovery step, and the other steps are the same. There is. Therefore, in the following description, the same reference numerals will be given to the common steps and those explanations will be incorporated, and different steps will be described in detail.

The manufacturing method 10C of the third embodiment is configured such that the manufacturing method 10A of the first embodiment has a charcoal mixing step 14A in which a predetermined amount of charcoal is mixed between the underwater stirring / crushing step 14 and the pulp recovery step 15. Have.

In this charcoal mixing step 14A, the charcoal material to be mixed is not limited to a specific one, and generally known charcoal such as charcoal and sludge charcoal is used. The use of these charcoals can induce their respective properties. For example, using sludge charcoal is cheaper.

The amount of charcoal mixed is preferably in the range of 10 to 30% by weight with respect to 100% by weight of the paper material. If the amount of this mixture is 10% or less, it becomes difficult to obtain the deodorant effect, and if it exceeds 30%, the color of the paper material becomes charcoal and the appearance deteriorates. This is because it becomes difficult to use as a raw material. The mixing amount of 10 to 30% by weight is in the range with respect to 100% by weight of the paper material, that is, the amount mixed in the paper material of the final product.

By mixing charcoal in this range, the deodorizing property can be further enhanced as compared with that of the first embodiment. Further, in methane fermentation using livestock manure mixed with this bedding as a raw material, it becomes a habitat for microorganisms, contributes to the growth of microorganisms, and improves and stabilizes methane production efficiency.

In this embodiment, the mixing of charcoal is a subsequent step of the underwater stirring / crushing step 14, but the underwater stirring / crushing step 14 may also be used. When mixed in this step, the charcoal is agitated and crushed in this step to obtain a desired size.

According to the production method of the third embodiment, the same action and effect as those of the production methods of the first and second embodiments can be obtained, and the deodorizing property can be further enhanced. That is, in general, charcoal is a non-polar substance and does not easily adsorb polar molecules such as ammonia, which is an odor component, but incompletely carbonized substances such as sludge charcoal can be adsorbed to some extent. Similarly, water is also a polar substance, and completely carbonized charcoal shows hydrophobicity and does not adsorb water, but general charcoal absorbs water relatively well, so water containing odorous components (manure water) is added to the litter. It can be stored in charcoal. In addition, since the apparent surface area of charcoal (the contact area between the stored moisture and the air or moisture outside the charcoal) is relatively small, the amount of odorous components evaporated from the stored moisture is relatively small, and the effect is greater than that of molded paper. Are better. Since the water absorption rate of charcoal is relatively slow, it is effective to use it together with paper.

That is, since the paper material produced in the third embodiment carries charcoal inside the paper, the paper quickly absorbs the water containing the odor component and then slowly absorbs it into the charcoal, so that the effect is immediate. The property and deodorant property can be enhanced. In addition, charcoal that has not touched manure, that is, has not yet absorbed water, is less effective, but absorbs the odor in the barn, so when there is a lot of litter that has not yet absorbed water at the beginning of laying, the odor in the barn When the water is absorbed by manure, odorous components such as ammonia in the water are also fixed in the charcoal at the same time, which has a two-stage deodorizing effect. Although these effects do not last very long, there is no problem with bedding such as dairy cows because they are used quickly.

The litter and charcoal can be prepared separately and mixed, but according to this manufacturing method, the charcoal can be supported inside the paper and the charcoal, which is relatively easy to separate, is separated in the pulp recovery process. There is no concern that the charcoal and the litter will be separated due to the movement of the cow and the bedding will not be uniform, and since it is easy to absorb water from the paper, the effect can be easily obtained. On the other hand, even if charcoal is mixed with dry crushed paper as in the prior art, it is easily separated during transportation and use, and adheres to a wet floor surface, making recovery difficult. Further, if it is attached with a binder, the same problem as that of the binder at the time of granulation occurs. Although charcoal serves as a habitat for microorganisms during methane fermentation and contributes to improvement and stabilization of methane production efficiency due to the growth of microorganisms, it is not a direct raw material for methane fermentation, so the upper limit of the amount added is 30%. Be restricted. From the above, it is possible to provide a litter that is cheaper and easier to use than the current sawdust, and the methane generation efficiency of methane fermentation is improved by using manure mixed with this litter.

<Experiment of deodorizing effect by mixing charcoal (Experimental Examples 26 to 31)>
Next, the characteristics of the paper material produced by this production method were confirmed by Experimental Examples 26 to 31.
First, a waste gypsum board is crushed, and a piece of paper having a side of 5 mm or more is separated as paper. Water is added to a piece of paper to which gypsum is attached, and the paper is stirred and dissociated with a screw to reduce sludge charcoal to 100% by weight of the paper material. After 10% by weight was mixed (Experimental Examples 26 to 28) or not mixed (Experimental Examples 29 to 31), the pulp obtained by filtering with a wire net having an opening width of 2 mm was further rinsed with water to remove gypsum. After that, it was placed in a mold, molded, and dried at 110 ° C.
The dried paper material was cut to prepare paper material samples of Experimental Examples 26 to 28 having a thickness of about 0.5 mm, 1 mm, and 2 mm in a 10 mm square. Ammonia water (odor source) was added dropwise to each of the paper samples of Experimental Examples 26 to 28 at 0.5 ml / g to 2 ml / g, and the intensity of the odor after 1 minute and 5 minutes was measured. The measurement results are summarized in Tables 5, 6 and 7 together with the amount of ammonia water dropped.

From the results shown in FIGS. 6, 7 and 5, the following was found.
That is, as shown in FIG. 6, the amount of dripping is small from the comparison between the paper material samples of Experimental Examples 26 to 28 (paper material mixed with charcoal) and the paper material samples of Experimental Examples 29 to 31 (without charcoal). In the case, the odor level from 1 minute to 5 minutes after the dropping of the ammonia water drops steeply on the right shoulder for any thickness of 0.5 mm, 1 mm, or 2 mm of the paper material, and each thickness. As for each odor level in the above, the paper material mixed with charcoal (Experimental Examples 26 to 28) has a lower odor level drop than the paper material without charcoal (Experimental Examples 29 to 31), and the deodorizing effect is improved. Further, as shown in FIG. 7, when the amount of dripping is large, the paper materials of Experimental Examples 26 to 28 (paper material mixed with charcoal) and the paper materials of Experimental Examples 29 to 31 (without charcoal) are compared. It descends to the right, and the gradient is gentler than when the amount of dripping is small (see FIG. 6). In this case as well, the deodorizing effect of the charcoal-filled paper material is improved.

As described above, from the comparison between the two, the paper material with and without charcoal has a high deodorizing effect in the former and the speed is faster in the former and slightly slower in the latter, depending on whether the amount of dripping is small or large. It turned out. In addition, these points have already been partially described in the use for the litter of the first embodiment.

A method for producing a paper material using a piece of paper separated from the waste gypsum board according to the fourth embodiment of the present invention as a raw material will be described with reference to FIG. FIG. 8 is a process block diagram of a method for manufacturing a paper material using a piece of paper separated from the waste gypsum board according to the fourth embodiment of the present invention as a raw material.

The method 10D for producing a paper material using the waste gypsum board separation paper according to the fourth embodiment intervenes a charcoal mixing step between the underwater stirring / crushing step and the pulp recovery step in the manufacturing method 10B of the second embodiment. The other steps are the same. Therefore, in the following description, common steps are designated by the same reference numerals and the explanations are incorporated, and different steps will be described in detail.
The manufacturing method 10D of the fourth embodiment has a configuration in which the manufacturing method 10B of the second embodiment has a charcoal mixing step 14A for mixing a predetermined amount of charcoal between the underwater stirring / crushing step 14 and the pulp recovery step 15. Have.

The charcoal mixing step 14A of the manufacturing method 10D of the fourth embodiment is the same as the charcoal mixing step 14A of the manufacturing method 10C of the third embodiment.
Therefore, according to the production method of the fourth embodiment, the same action and effect as the production methods of the second to third embodiments can be obtained, and the deodorizing property can be further enhanced. That is, in general, charcoal adsorbs only a small amount of ammonia, which is the main odor component, but water containing the odor component (manure water) can be stored in the charcoal in the litter, and the apparent surface area (stored). Since the contact area between the water and the air or the water outside the charcoal is small, the amount of evaporation of the odorous component from the stored water is relatively small, and the effect is superior to that of the molded paper.

10A-10D Paper material manufacturing method 11 Waste gypsum board 12 Crushing process 13 Paper piece recovery process 14 Underwater stirring / crushing process 14A Charcoal mixing process 15 Pulp recovery process 16 Paper material forming process 16 ₁ Squeezing part 16 ₂ Crushing part 17 Drying process 18 Paper material P1 Paper piece P2 Waste paper

The tenth paper material of the present invention is characterized in that it is formed of a molded product or processed product having a predetermined shape containing dihydrate gypsum , which is produced by the production method according to any one of claims 1 to 7.

According to the paper material of the tenth aspect of the present invention, pulp containing dihydrate gypsum can be made into a molded product or processed product having a predetermined shape to be compatible with and suitable for various uses.

Claims (11)

Waste gypsum board separation A piece of paper was put into water to subdivide and separate the pulp adhering to the piece of paper, and the piece of paper was kneaded to disperse and suspend the plant tissue in water to elute water-soluble components and the like. An underwater stirring / crushing step to generate a pulp liquid, a pulp recovery step to separate plaster, easily free pulp, water-soluble components, etc. and water from the pulp liquid and recover the pulp, and paper for forming the pulp into a predetermined shape. A method for producing a paper material using waste gypsum board separated paper as a raw material, which comprises a material forming step and a drying step of drying the paper material at a predetermined temperature. The paper material made from the waste gypsum board separation paper according to claim 1, wherein the paper piece is preheated to a temperature range of 128 ° C. or higher and lower than 163 ° C. in the underwater stirring / crushing step. Production method. The method for producing a paper material using the waste gypsum board separation paper as a raw material according to claim 1 or 2, wherein a predetermined amount of used paper is mixed in the underwater stirring / crushing step. The method for producing a paper material using the waste gypsum board separation paper as a raw material according to any one of claims 1 to 3, wherein a predetermined amount of charcoal is mixed in the underwater stirring / crushing step. The method for producing a paper material using a piece of paper separated from the waste gypsum board according to any one of claims 1 to 4, wherein the recovered pulp is washed with water and dehydrated in the pulp recovery step. Paper made from a piece of paper separated from the waste gypsum board according to any one of claims 1 to 5, wherein the water content after molding is in the range of 50 to 80% by weight in the paper material molding step. Material manufacturing method. The method for producing a paper material using the waste gypsum board separation paper as a raw material according to any one of claims 1 to 6, wherein the drying step is performed at a temperature of less than 128 ° C. A crushing means for crushing a waste gypsum board into a predetermined shape or size, a paper piece collecting means for separating and collecting a piece of paper from the crushed material, and a means for collecting the piece of paper and kneading it to disperse and suspend the plant tissue in the water. An in-water stirring / crushing means that produces a pulp liquid that is turbid and elutes water-soluble components, etc.
Gypsum, easily free pulp, water-soluble components, etc. contained in the pulp liquid, a pulp recovery means for separating and recovering pulp by separating water, a paper material molding means for molding the pulp into a predetermined shape, and the paper material. A paper material manufacturing apparatus comprising: a drying means for drying at a predetermined temperature. The paper material manufacturing apparatus according to claim 8, wherein the pulp recovery means is provided with a washing / dehydrating unit for washing and dehydrating the recovered pulp. A paper material formed of a molded product or processed product having a predetermined shape, which is produced by the production method according to any one of claims 1 to 7. An animal litter, which comprises the paper material according to claim 10.

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