JP5066769B2 - White line powder derived from waste gypsum board, and method for producing white line powder - Google Patents

Description

  The present invention relates to a technical field of recycling in which waste gypsum board as industrial waste is reused.

  Gypsum board is widely used as a building material mainly because of its low cost and excellent fire resistance. When a gypsum board is used in a building site of a building, a so-called new building material of the remaining gypsum board that is cut in accordance with the size of a use site is generated. Further, when demolishing existing buildings, so-called demolished waste material of waste gypsum board is generated. A method for treating the waste gypsum board generated in large quantities as industrial waste has been studied.

  As a method for treating waste gypsum board, there is a method of incineration disposal, but there is a problem that toxic gas is generated at the time of incineration, and incineration disposal also has problems of energy consumption and impact on global warming. At present, waste gypsum board is mainly disposed of by landfill. However, landfilling has a problem of securing space and environmental problems such as generation of hydrogen sulfide, and is not generally desirable as a treatment method. Therefore, a method for reusing waste gypsum board as a recycled resource is desired.

As a technology to recycle waste gypsum board, means for sorting pulverized waste gypsum board for different substances and reusing each of them is studied, sorting by particle size (vibrating sieve), sorting by specific gravity ( A method of separating gypsum powder, paper pieces, paper powder, and metal pieces by using a combination of inertia sorting), wind classification (wind suction), magnetic sorting, and metal detection is disclosed (for example, Patent Document 1).
In addition, a method is disclosed in which pulverized waste gypsum board is separated according to a mesh, paper powder is collected into a pill shape by a diaphragm, and the pill is blown off with a predetermined air volume (for example, Patent Document 2).

  On the other hand, white lines corresponding to competitions and events are drawn on grounds such as school playgrounds and stadiums, and white slaked lime is generally used as the white line drawing powder. Since the slaked lime is strongly alkaline, it may cause inflammation if it adheres to the skin or the mucous membrane of the nose.

  Therefore, it is known that instead of slaked lime, calcium carbonate powder obtained by pulverizing limestone or eggshell, or gypsum powder produced by precipitation in a solution is used as a highly safe line drawing powder (for example, patent document). 3-5).

JP 2000-70915 A Japanese Patent Laid-Open No. 10-286553 JP 2004-261213 A Japanese Patent Publication No. 5-35685 Japanese Examined Patent Publication No. 4-72557

  The gypsum board recycling apparatus of Patent Document 1 employs a classification method of separating the pulverized waste gypsum board by particle size using a vibration sieve and specific gravity by inertia sorting. However, the apparatus configuration is very large. It is not easy to install.

  In Patent Documents 1 and 2, so-called demolition waste material generated when demolishing an existing building is used as a waste gypsum board. However, the use of the existing building gypsum board is currently restricted. Some of them contain harmful substances, and if they are pulverized, there is a risk of generating fine powders that are particularly harmful to health and the environment.

  In addition, waste gypsum boards used in buildings contain various impurities other than plaster pieces and paper pieces, including metal such as nails, as they are used during construction, as well as during building dismantling and collection. There are cases where a large amount is mixed, and there are significant problems with equipment and labor, time, and cost for removing them. In fact, as in Patent Document 1, including magnetic sorting and metal detection has a large equipment configuration. It is also a cause of complexity on the scale.

  Furthermore, the quality of gypsum and paper used in existing buildings is not constant depending on age and environment, and there may be inconveniences in crushing and sorting, and the quality of powder derived from waste gypsum board is also low. It turns out that there is a problem that it may not be stable.

On the other hand, the calcium carbonate powder and gypsum powder of Patent Documents 3 to 5 are not yet sufficient in performance such as line drawing workability and stability. These powders obtained by pulverizing mineral raw materials are fine particles with little surface irregularities, and therefore have a drawback of being easily scattered after drawing a line.
In addition, since the particle density is high, the weight per area (length) of the drawable line increases, and a large amount of powder is consumed when drawing a large amount of line to the ground using a line drawing machine. Was to be done.
Furthermore, it was a heavy labor in the work of filling the powder into the line drawing machine and the line drawing work.

  Therefore, in view of the above situation, the present inventors have conducted intensive research focusing on using waste gypsum board as a raw material for line drawing powder. In particular, the focus was on exclusively using new gypsum board materials that are free from harmful substances and impurities such as metals, and that can provide raw materials of a certain quality. As a result, it was found that paper powder would be a problem in order to reuse the crushed waste gypsum board as white line powder.

In Patent Document 1, a piece of paper generated from the surface of the waste gypsum board at the time of crushing is removed, but attention is not paid to the finer paper powder generated by cutting the paper on the surface at the time of crushing the waste gypsum board. Actually, separation by the method of Patent Document 1 is considered possible to separate and remove paper pieces, but removal of paper powder has not been solved.
According to the knowledge of the inventors, it has been detected that the paper powder is 5 mm to 10 μm in length as shown in FIG. 10, 10 μm to 100 μm in width, and extremely finely pulverized into short fibers.

In Patent Document 2, small crushed pieces that have passed through a 2 mm sieve are finely shaken on the vibration plate 34 along the horizontal direction, so that the mixed fine paper powder is put into a pill shape, and then blown and sucked later. Discloses a technique for removing pills.
However, if the vibration is only applied in the horizontal direction on the diaphragm, the paper powder fibers are not subjected to any force other than tangling with each other, and the pills cannot be grown sufficiently and quickly. It was a thing.
When trying to remove the pills by blowing or sucking, the gypsum content of the small pieces and the paper powder will be blown off and removed, so it is not allowed to remove only the pills of the paper powder. It is.

  Here, although there are many types of line drawing machines currently in use, the supply system of the powder supply unit (rotary device for supplying powder to the discharge unit) and the discharge unit (powder discharge) The hole structure and dimensions of the hole to be used are different for each model. As the supply method, for example, a brush type in which a brush is erected radially around the axis, a paddle type in which a paddle is erected around the axis, etc. are provided, and the discharge part includes a slit, a square hole, a mesh Hole structures such as holes and round holes and various dimensions are provided. Therefore, when filling the above powder into the line drawing machine of each model and drawing the line, all models can draw a desired line at the beginning, but if the line is drawn beyond a certain distance, the line will be It turned out that there was a model that became thin or unable to draw a line.

When the line drawing machine was inspected, it was found that paper powder entangled with the powder supply part or paper powder blocked the discharge part.
If the paper powder remains in the gypsum pulverized product, the paper powder adheres to the powder when it is used as a line drawing powder. The fluidity of becomes worse. As a result, supply and discharge are hindered inside the line drawing machine during line drawing. For example, even if the particle size of the powder itself is small, the longer the line is drawn, the more the paper powder adheres to each other and grows as a larger lump, so that the powder is not discharged from the hole diameter of the discharge portion. From these phenomena, line drawing stability and operability were lacking.

Also, the powder with paper powder adhered to the line drawing machine easily adheres to the inside of the machine or to the paddle and brush for discharging due to entanglement of fiber of the paper powder. There is a problem that smooth and uniform line drawing cannot be performed.
Furthermore, even in the drawn line, there are problems such as a large lump shape due to the mixing of the paper powder, unevenness in the drawn lines, and scattering of the paper powder (including static electricity).

  In addition, depending on the degree of mixing of the paper powder, the color of the paper powder is mixed, so that the line color is not clear. Furthermore, when it rains, the line changes color and becomes unclear. Because of these problems, the pulverized material obtained by the conventional fractionation method newly faced the problem that it cannot be suitably used as a powder for white line.

Therefore, when the gypsum content of the waste gypsum board is used as a line drawing powder, the present inventors have to answer the following technical problem in addition to the removal of paper powder.
First, the line drawing powder is required to have light weight and grip properties, but generally, the pursuit of the light weight lowers the grip performance, and the pursuit of the grip performance impairs the light weight. Since the powders described in Patent Documents 3 to 5 have a high particle density, a large amount of powder is required for line drawing, and workability by the line drawing machine is not improved.
Here, the gypsum hardened body, which is the core material of gypsum board, has a structure in which rod-shaped dihydrate gypsum (CaSO ₄ · 2H ₂ O) single crystals that are three-dimensionally extended in various directions are intertwined with each other, and there are many per volume. With a void. Therefore, paying attention to the rod-shaped crystal that is a single crystal of dihydrate gypsum (CaSO ₄ · 2H ₂ O) for gypsum, and utilizing the high porosity when the rod-shaped crystals are entangled with each other, the weight of the powder can be reduced. As a result, the powder consumption for line drawing also decreases. As the white wire powder, a particle density of 0.70 to 1.20 g / cm ³ was good. With respect to the aggregated particles, it was found that the rod-like portions of the entangled rod-like crystals protruded from the aggregated sites, and thus it was confirmed that the grip properties were good.
Secondly, compatibility between the existing line drawing machine and the powder composed of the aggregated particles is required. When experimenting with filling each line drawing machine model, when the aggregated particle diameter exceeds 1000 μm, the drawn line is not clear, but when it becomes 100 μm or less, it reassembles into a large lump. It became clear that the inside was blocked and no longer discharged. The compatibility was good when the particle size was in the range of 100 to 1000 μm. In addition, it was found that the line could be satisfactorily drawn by conducting an experiment by filling each model of the line drawing machine with a powder having a weight ratio of 0.85% or less.

  As described above, the present inventors pulverized a new end material of waste gypsum board, obtained a powder obtained by removing paper powder from the pulverized product, and entangled rod-like crystals, resulting in low particle density and grip properties. The present invention was completed by finding that the obtained powder could be a powder for line drawing with excellent performance, with the aim of obtaining a powder composed of aggregated particles having a large number of particles.

  In order to achieve the above object, the present invention provides the following white line powder derived from waste gypsum board.

The white wire powder derived from waste gypsum board according to claim 1 of the present invention is a piece of paper and paper powder resulting from a base paper that covers the waste gypsum board from a pulverized product produced by pulverizing a newly constructed waste gypsum board. The powder was obtained by removing rod crystals having a width of 0.3 to 2.0 μm and a length of 1.0 to 10 μm, and a particle diameter of 100 to 1000 μm. It is characterized by comprising aggregated particles having a density of 0.70 to 1.20 g / cm ³ .

  Further, in the white wire powder derived from waste gypsum board according to claim 2 of the present invention, the aggregate particles are substantially spherical, and rod-like crystals protrude from the surface of the spherical body. To do.

In addition, the method for producing a white wire powder derived from waste gypsum board according to claim 3 of the present invention includes a pulverization step of pulverizing a newly constructed scrap of waste gypsum board, and a pulverized product obtained in the pulverization step. A separation process for separating the paper into pieces of paper, and the crushed material that has passed through the separation process, by means of a sieve having a vibration mechanism having a three-dimensional rotational movement such as horizontal, vertical, and inclined. The upper sieve process in which the aggregated particles pass and the paper powder of the paper stays, and the three-dimensional horizontal, vertical, and inclined with respect to the pulverized product that is installed below the upper sieve process and passes through the upper sieve process. And a lower sieving step in which aggregated particles of gypsum pass through a sieve having a vibration mechanism having a rotational motion and paper powder of paper stays.

Moreover, the manufacturing method of the powder for white line | wire derived from the waste gypsum board which concerns on Claim 4 of this invention is characterized by having an opening of 1000-250 micrometers, and the opening of several steps | paragraphs of upper and lower sides is the same.

Further, in the method for producing a white line powder derived from waste gypsum board according to claim 5 of the present invention, the mesh opening is 1000 to 250 μm, and the upper and lower multi-stage openings are smaller toward the lower side. .

According to the white wire powder derived from waste gypsum board according to the present invention, paper powder can be removed and aggregated particles having a low particle density can be supplied as a recycled product having a particle size configuration. As a result, when drawing a line with a line drawing machine, good supply and discharge can be obtained without clogging the inside, and since it is lightweight, it has good operability and can be drawn over a long distance. It can be used as white wire powder corresponding to each type of puller.
In particular, since paper powder is prevented from being mixed into the white line powder, it is possible to eliminate problems such as paper powder fibers becoming entangled in the interior and in the paddle and brush for discharge. Each function of the line drawing machine of each model can be exhibited.

According to the white wire powder derived from the waste gypsum board according to the present invention, after the powder is aggregated with rod-like crystals having a width of 0.3 to 2.0 μm and a length of 1.0 to 10 μm, the main constituent particles It can be composed of aggregated particles with a diameter of 100 to 1000 μm and a particle density of 0.70 to 1.20 g / cm ³ , greatly reducing the amount of consumption when drawing a line, and reducing environmental impact It becomes.

  Further, according to the white line powder derived from waste gypsum board according to the present invention, the white line is clearly formed by the removal of the paper powder and the particle diameter, the color of the paper powder is not mixed, and the white line is clear It is also superior. In addition, since the drawn lines are less mixed with paper powder, the drawn lines are not uneven and a beautiful line can be provided over a long distance.

  Further, according to the white line powder derived from the waste gypsum board according to the present invention, the white line powder may be partly collapsed and become primary particles after drawing because of the aggregate particles mainly composed of rod-like crystals. The line has good fixability and is difficult to scatter, and undisintegrated aggregated particles have many irregularities, so they are often caught on the ground, and are difficult to scatter due to wind, etc. Become.

  Moreover, according to the white wire powder derived from the waste gypsum board according to the present invention, no harmful substances are mixed in to use the newly constructed scrap, and there is no adverse effect on health and the environment. It is possible to obtain a relatively large amount of new construction waste materials with a certain quality of powder.

  Further, according to the white wire powder derived from waste gypsum board according to the present invention, the aggregate particles constituting the powder are substantially spherical, so there is little variation in physical properties from powder to powder, and it is difficult to collapse. In line drawing machines, they are hard to get tangled with each other. Furthermore, since rod-like crystals protrude from the surface, on the other hand, when drawing a line, the line is easily caught on the ground and the line is stable.

  Moreover, according to the white line powder derived from waste gypsum board according to the present invention, the properties of each powder are stabilized and the line is stabilized because the average particle diameter of the powder is within a certain range. In addition, the weight of the powder per line area of the drawn white line is less than the value of the conventionally used white line powder, and it is possible to draw a long line with a lightweight powder. The burden of work is reduced and the cost of powder per line is low. In the case of a dense dice-like gypsum powder of 75 μm or less produced in a basic aluminum chloride salt solution used as a conventional white wire powder, or a gypsum powder obtained by pulverizing natural gypsum, the area per line area 10 × 10 cm The weight of the powder is about 5.0 to 15.5 g using the smallest to largest of the line drawing machines that are generally used, but it is derived from the waste gypsum board according to the present invention. When the white wire powder is used, the weight is 0.8 to 4.8 g, and a line having the same area can be drawn with a weight of about one third.

  Furthermore, according to the method for producing white wire powder derived from waste gypsum board according to the present invention, in the upper sieving step, the pulverized material containing paper powder is supplied to the center of the sieving surface, Three-dimensional rotational movement such as vertical and tilt acts. In addition, by controlling the phase angle of the upper and lower weights of the motor shaft of the vibration sieving machine to 30 to 40 degrees, the pulverized material containing paper powder swirls on the sieving surface to form a gypsum assembly. The particles are discharged under the sieve, and the paper powder is entangled with each other, moves to the outer periphery, and is discharged. Also in the lower sieving step, the gypsum aggregate particles are discharged under the sieving by the same mechanism, and the paper powder is entangled with each other and moved to the outer peripheral portion and discharged. The removal of paper powder is difficult with a method mainly using horizontal vibration using a sieve such as an inclined plate, and with this method mainly using three-dimensional rotational motion, paper can be removed with high efficiency. The powder can be sufficiently removed.

  Furthermore, according to the manufacturing apparatus used in the method for manufacturing the white wire powder derived from the waste gypsum board according to the present invention, even if the upper and lower openings are configured to have the same dimensions, the paper that has passed through the upper openings When the powder is in an intersecting posture with respect to the mesh of the sieve, it stays, and the residence time becomes longer and the paper powder is removed.

  In addition, according to another manufacturing apparatus used in the method for manufacturing a white line powder derived from waste gypsum board according to the present invention, the lower opening is small, so the paper powder that has passed through the upper opening intersects. In addition to the case of the posture, even if the posture is not the crossing posture, it stays according to the small opening, and the residence time becomes longer and the paper powder is removed.

  FIG. 1 is a schematic diagram showing a white line powder according to Embodiment (1) of the present invention, and FIG. 2 shows a method for producing a white line powder derived from waste gypsum board according to Embodiment (1) of the present invention. FIG. 3 is a schematic view showing a sieving step of a method for producing a white wire powder derived from waste gypsum board according to Embodiment (1) of the present invention.

The white wire powder 22 shown in FIG. 1 is obtained by crushing a newly constructed scrap of waste gypsum board, and removing paper fragments and paper powder resulting from the gypsum board base paper covering the surface of the waste gypsum board from the resulting pulverized product. It consists of the powder obtained. The white wire powder 22 is composed of aggregated particles 23... In which gypsum crystals are aggregated. The aggregate particles 23 have a particle diameter of 100 to 1000 μm and a particle density of 0.70 to 1.20 g / cm ³ . The aggregate particle 23 is formed by a collection of rod-like crystals 24 having a width of 0.3 to 2.0 μm and a length of 1.0 to 10 μm.

As described above, the rod-shaped crystal 24 has a structure in which rod-shaped single crystals of 2-hydrate gypsum (CaSO ₄ · 2H ₂ O) are intertwined with each other. It is a curved crystal. The aggregated particles 23 are a collection of a large number of them, and as a whole constitute substantially spherical particles. As used herein, the term “spherical” refers to a particle having no corners as a whole shape of aggregated particles, a surface whose surface is substantially composed of a curved surface, and includes a distorted material such as a particle whose circumference includes an ellipse. The aggregated particles 23 have a three-dimensional network with irregular meshes formed by the rod-like crystals 24, and there are a large number of voids 25 in the mesh, which makes the particle density low.

  The aggregated particles 23 have a protruding portion 27 formed on the surface of the outer edge thereof by projecting a large number of ends of the rod-like crystals 24. Therefore, the surface of the aggregate particle 23 has innumerable protrusions 27 protruding in various lengths and angles, and various irregularities are formed over the entire outer periphery. Furthermore, the rod-like crystal 24 often has a corner 28 having a square shape, and the protrusion 27 is likely to be caught by surrounding substances. Therefore, the surface of the aggregate particle 23 has a grip structure that can be caught outside at various angles and depths.

  The aggregated particles 23 preferably have a constituent particle diameter in the range of 100 μm to 1000 μm. Particles of less than 100 μm are not preferably contained in a large amount because the particles tend to reassemble with each other and so-called bridging phenomenon tends to occur. Further, particles having a size of 1000 μm or more may be too large to be easily discharged depending on the structure of the line drawing machine.

  The aggregated particles 23 desirably have an average particle size of 125 μm or more and 850 μm or less and a uniform particle size distribution. Further, when the particle size distribution is configured to be 50% or more at 125 to 600 μm, stable line supply from the line drawing machine is possible, and there is an advantage that scattering is extremely small when filling the line drawing machine. There is.

Particle density of the white line for powder 22 is in ^the range of 0.70g / cm ³ ~1.20g / cm 3 is desirable. When the value exceeds 1.20 g / cm ³ , the particles are heavy and the line drawing operability is poor. If it is less than 0.70 g / cm ³ , the particles are lightweight, but there are too many voids in the particles and the particle strength becomes small, so they can be broken and atomized even during transport and bag filling. There is sex. Furthermore, when the density of each aggregated particle 23 is constant, the behavior as a line is stabilized, and therefore, it is selected from a certain narrow range such as 0.70 to 0.90 g / cm ³ .

  If the said paper powder is 1.0 weight% or less, it can be utilized without trouble in various line drawing machines. When the content of the paper powder is 0.85% by weight or less, a white line powder sufficient to make the line clear with little color from the paper powder as an impurity is obtained. Further, when the paper powder is 0.65% by weight or less, even if a line drawing machine having a minimum value for each of the current supply unit and the discharge unit is configured, the supply and discharge are not hindered.

  The white line powder 22 preferably has a line area within a suitable range of discharge weight per 10 cm × 10 cm when the line is drawn. The appropriate discharge amount of the white wire powder 22 greatly depends on the structure of the supply unit and discharge unit of the line drawing machine, and the appropriate amount varies depending on the structure. When used, it is in the range of approximately 0.8 to 4.8 g. Generally, when the supply part is a brush type or when the discharge part is a slit type, the discharge amount is small, but even when using a brush type and slit type line drawing, it is sufficient if it is less than 0.8 g. Emission amount. In addition, when the supply part is a paddle type and the discharge part is a round hole type, the discharge amount increases. However, even when the paddle type and round hole type are used, the discharge amount does not exceed 4.8 g and the discharge amount is not too large. desirable. More preferably, from the relationship between the weight of the powder and the area of the line, the line that is not too thin and not too dark is in the range of 0.9 to 4.0 g. A white line powder having a uniform particle density and removing paper powder has a value of 1.0 to 3.6 g, and is most preferably within this range.

  Since this powder has a particle density smaller than that of a conventionally used line drawing powder, it is lightweight and can draw an equivalent line. For example, in the case of gypsum powder obtained by pulverizing a gypsum mineral raw material used as white wire powder, the discharge weight per 10 cm × 10 cm is about 3.5 to 10.0 g. The white line powder draws a line with the same area with a lighter discharge weight than the conventional gypsum powder, and as a guide, when the line is drawn by the same line drawing machine using the same weight powder, Lines up to 3.0 times longer can be drawn.

  Next, the suitable manufacturing method of the powder for white line derived from the waste gypsum board of Embodiment (1) is demonstrated based on FIGS.

  First, in the pulverization step 1, the waste gypsum board 2 is pulverized (pulverized), and then classified according to particle size by passing through a sieve 3, and then subjected to a separation step 4 to remove paper pieces from the pulverized product 5. . The pulverizing device used in the pulverizing step 1 can be performed using a known waste gypsum board pulverizing device, and the separating device used in the separating step 4 is to remove a piece of paper using a known separating device using wind power. Can do. The pulverization step and the separation step may be performed a plurality of times. In the example shown in the figure, the pulverization step and the separation step are each repeated three times to adjust the particle size and remove the paper pieces.

  Next, the pulverized product 5 is further subjected to a paper powder removing step 6. The paper powder removal sieving process 6 includes a coarse sieving process 7, an upper sieving process 8, and lower sieving processes 9 and 10.

  In the coarse sieving step 7, the pulverized product 5 is applied to the coarse sieve 11 to classify the coarse powder 12, which is a coarse gypsum pulverized product, and the remaining paper pieces and large paper powder, and the pulverized product 13 after removing the coarse powder. Get.

  The upper sieving step 8 and the lower sieving steps 9 and 10 are steps for separating the paper powder still contained in the pulverized product of the gypsum of the pulverized product 13 that has passed through the coarse sieve 11 from the pulverized product 13. In the upper sieving step 8, the pulverized product 13 is put on the upper sieving 14, the pulverized product 13 containing the paper powder is swirled on the vortex on the sieving surface, and the aggregated particles 23 are discharged below the upper sieving 14, and the paper powder Is entangled and discharged to the outer periphery as a hairball shape. The upper sieve 14 desirably has an opening of about 0.25 to 1.0 mm. When the mesh opening is 0.25 mm or less, the removal rate of the paper powder is high, but the clogging of the sieve is severe and the yield is low. When the mesh size is 1.0 mm or more, the yield is good, but the residence time on the sieve is short and the paper powder removal rate is low. Furthermore, considering the range in which the yield and the removal rate can be compatible, a mesh opening of 0.5 to 0.85 mm, which is the middle, is the most effective.

  On the upper sieve 14, the pulverized material 13 containing paper powder is supplied to the approximate center 14 </ b> A of the upper sieving surface, and the pulverized material 13 is subjected to rotational movement in three-dimensional directions such as horizontal, vertical, and inclined. To do. The vibration sieving machine is installed below each of the sieves 14, 20, and 21 in the paper powder removing process 6, and the phase angle of the upper and lower weights of the motor shaft 29 that is the center of the sieving machine is 30 to 40 degrees. The flow of the powder is controlled by the spiral movement 15, and the relatively heavy powder 16 gathers at the center C on the sieve, and the light paper powder swirls outward and rotates vigorously. Inside, paper fibers are entangled to form pills. When a pill is generated, it becomes more susceptible to vibrations and rotational movements, so that it is further granulated and coarsened, and many paper fibers can be made into large pills. The outer paper ball 17 is trapped by the partition 18 provided on the outermost side of the sieve and discharged from the waste outlet 19.

  The gypsum content that has passed through the upper sieve 14 in the upper sieve process 8 is further provided to the lower sieve process 9. The lower sieving step 9 is desirably performed under conditions selected from the same range as the upper sieving step 8. A plurality of lower sieving steps 9 and 10 may be provided. The higher the number of stages of the sieving process, the higher the removal rate, but 2 to 4 stages are appropriate from the viewpoint of the complexity, cost, and time of the manufacturing process. In the figure, two stages of lower sieving steps 9 and 10 are provided, and each lower sieving 20 and 21 has the same opening and process conditions as the upper sieving 14, and a means of providing a total of three stages of sieving is used. Yes.

  The separation of the paper pills 17 using a plurality of sieving steps is such that when vibration is applied to the sieves 14, 20, and 21 in which a plurality of steps are overlapped, particles whose diameter is extremely smaller than the mesh opening speeds up the sieving steps. Passing through, but long particles of any diameter are likely to stay, so the time for staying on the step is long and they pass slowly. Therefore, in this embodiment (1), the aggregated particles 23 that are small particles pass through the multistage sieve, but the fibers of the paper powder that are elongated particles having a fibrous long particle shape remain in the sieve for a long period of time. . Therefore, since the paper fibers are exposed to the spiral motion on the sieve for a long time, the fiber shape is entangled and a large paper fluff 17 is rapidly formed. By simply applying vibration in a single direction, or simply vibrating with gypsum particles using a diaphragm or a single-layer sieve, it is not possible to form such large pills rapidly or without mixing gypsum powder. .

  Thus, the white line powder 22 derived from the waste gypsum board according to the embodiment (1) of the present invention is obtained by collecting the pulverized product of the gypsum from which the paper powder has been removed after passing through the paper powder removal step 6. Can be manufactured.

  As embodiment (2) of the present invention, in the upper sieving step 8 and the lower sieving steps 9 and 10 of the paper powder removing step 6, the diameters of the openings of the sieves 14, 20, and 21 are gradually reduced from the upper side to the lower side. Otherwise, the manufacturing method similar to that of the embodiment (1) can be adopted. In this case, compared with the embodiment (1), because it takes time to separate and a large amount of raw material is required to select the raw material with high accuracy, the manufacturing cost is increased, but the paper powder removal rate is Higher and less variable in particle size.

  Further, as the embodiment (3), the paper powder removing sieving step 6 may take a means for giving regular pulsation or the like to the inclined plate type sieving device other than the circular sieving device or the stirring type sieving device. Specifically, it is possible to granulate and remove paper powder in a continuous processing method in a rotating container such as a drum granulator, or in a process accompanying rotational movement such as a dish-type granulator. The removal rate of the paper powder granulation / removal in the embodiment (1) is particularly high.

  Furthermore, as another embodiment (4), as a coarse sieve, for example, a circular vibration sieve device, an inclined plate type vibration sieve, a stirring type sieve device or the like can be used. Moreover, as a paper powder removal sieve, it can carry out, for example using a circular vibration sieve apparatus, an ultrasonic vibration sieve apparatus, etc.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples.
[Example 1]

  100 parts by weight of waste gypsum board scraps, which are newly constructed waste materials, were pulverized to a pulverized particle size of 5 cm or less in the primary pulverization step 1 and classified on a sieve 3 having an opening of 1.5 cm. The obtained gypsum content is pulverized to a pulverization particle size of 10 mm or less in the secondary pulverization step 1 and classified through a sieve 3 having an opening of 10 mm, and then the gypsum content that has passed through the sieve 3 is subjected to the secondary separation step 4. It was again separated into gypsum and paper pieces by a pulverizer. The obtained gypsum content is pulverized to a pulverization particle size of 3 mm or less in the third pulverization step 1 and classified through a sieve 3 having a mesh opening of 3 mm, and the gypsum content that has passed through the sieve 3 is then subjected to the cylindrical vibration of the third classification step 4. It was again separated into gypsum and paper pieces with a sieving machine. Thus, the pulverized product 5 of the gypsum obtained in the third fractionation step 4 was classified as a coarse powder removal step 7 through a vibrating sieve having an aperture of 0.85 mm. Next, the pulverized product 13 of the gypsum is successively passed through a three-stage circular vibration sieve device having an aperture of 0.60 mm, which is the upper sieving step 8 and the two-stage lower sieving steps 9, 10. , 20 and 21, the paper powder contained in the pulverized product of the gypsum is discharged out of the system simultaneously with the classification, and the white line powder 22 that has passed through the final-stage third-stage sieve 21 is obtained in Example 1. Got as. At this time, the flow angle of the paper powder in each stage of the screen is such that the residence time is long on the sieve and the phase angle of the weights above and below the motor shaft 29 of the vibration sieve machine so that the fiber-shaped paper powder can be easily separated. Was controlled to 30 to 40 degrees, the pulverized product was swirled on a spiral, and the paper ball 17 was discharged out of the system. The amount of the target powder obtained was 65% by weight.

  In FIG. 4, the scanning electron micrograph of the whole image of the aggregated particle 23 of Example 1 is shown. The entire image of the aggregated particles 23 is a lump and indicates that there are fine irregularities on the surface. FIG. 5 is an enlarged photograph of the particle surface. It shows that the aggregate particle 23 is an aggregate of rod-shaped crystals 24 of various sizes.

  FIG. 6 shows a scanning electron micrograph of the entire image of gypsum powder produced in a basic aluminum chloride salt solution used as a conventional white wire powder as Comparative Example 1, and FIG. An enlarged photograph is shown. Unlike Example 1, both the particle surface and the whole image are composed of square crystals with few irregularities.

  The particle size constitution of Example 1 (by sieving method) was as shown in Table 1. It shows that 69.1% is constituted mainly by the particle size distribution of 74 to 850 μm, particularly 125 to 600 μm.

Further, the average particle diameter and particle density of the white wire powder 22 of Example 1 were as shown in Table 2. Table 2 shows the average particle diameter and the particle density of the white wire powder of calcium carbonate powder conventionally used as Comparative Example 1 and Comparative Example 2.

  Further, the white line powder 22 of Example 1 was completely removed from the paper piece. FIG. 8A shows the raw material powder before the paper powder removal step, FIG. 8B shows the white line powder 22 after the paper powder removal, and FIG. 10 shows the paper powder removed.

  Furthermore, the content of the paper powder of Example 1 was also measured. A prescribed amount of the white wire powder 22 of Example 1 was taken, and after weighing the initial weight, the weight after heating at 80 ° C. for 3 hours with a dryer was measured, and the content of adhered water was calculated. Then, the weight before and after heating at 200 ° C. for 3 hours with a dryer was measured, and the value obtained by dividing the weight loss by the initial weight was taken as the content of crystal water. Thereafter, the weight before and after heating at 500 ° C. for 3 hours in a heating furnace was measured, and the value obtained by dividing the weight loss by the initial weight was taken as the paper powder content. As a result, the content of the paper powder of Example 1 was 0.65% by weight.

  In addition, the stability of the discharge amount from the line drawing machine of Example 1 was determined by using the product name “510N type” (Evenue) as the line drawing machine, placing the line drawing machine on the ball mill mount and rotating at 60 rpm. The tire was rotated in minutes and the discharge volume was measured. The results are shown in Table 3. In Table 3, the measurement result of the same measurement performed about Comparative Examples 1 and 2 was written together. Example 1 shows that the weight is much lighter than Comparative Examples 1 and 2 (the particle density is small as shown in Table 2), and equivalent discharge (line area) can be obtained.

  Further, for Example 1 and Comparative Example 2, a “510N type” (manufactured by Evenew) was used as the line drawing machine, the line drawing machine was placed on the ball mill mount, and the tire was rotated 160 times at a rotation speed of 60 rpm. After discharging the powder, a line was drawn to compare the uniformity of the drawn line. FIG. 9A shows the line drawn in Example 1, and FIG. 9B shows the line drawn in Comparative Example 2. The line drawn in Example 1 was more uniform in powder state and line density than the line drawn in Comparative Example 2.

  Further, when the line was drawn using 1000 g of each powder of Example 1, Comparative Example 1 and Comparative Example 2 and “510N type” (Evenue) as a line drawing machine, the length of the line that could be drawn However, Example 1 was 196 m, calcium carbonate powder was 66 m, and gypsum powder was 54 m.

  The above results show that the white line powder derived from the waste gypsum board of the present invention has a smaller particle density and a longer line per unit weight than the conventional calcium carbonate powder and gypsum powder for line drawing, This indicates that the drawing can be performed more uniformly and the line drawing operability and stability are excellent.

  Next, using the powder of Example 1, the discharge state and the state of the drawn line were compared for each structure of various line drawing devices. This was performed for each apparatus having various structures of a supply unit (a rotating device for supplying powder to the discharge unit) and a discharge unit (hole through which the powder was discharged). The discharged state was measured by rotating the wheel on a ball mill stand. The state of the line estimated the discharge amount of 100 m from the outer peripheral length of the wheel, and checked the state by drawing the line after discharging 100 m. The results are shown in Table 4.

These results show that the powder of the present invention can be used without any major problems regardless of whether the supply part is a brush / paddle and the discharge part is a slit / mesh or various holes. In addition, it has been clarified that good results are obtained particularly when the supply section is a paddle type and the discharge section is a mesh and hole type.

  Next, when line drawing of 100 mx 5 cm is performed on Example 1 and Comparative Example 1 for each of the line drawing machines A, D, and E having different structures of the supply section and the discharge section, the area per area of 10 cm x 10 cm Emissions were measured. The results are shown in Table 5.

When the same line drawing machine is used, the powder of Example 1 shows a value close to that of Comparative Example 1 used in the volume of discharge (cm ³ ), and the line density does not change. Show. Furthermore, in the weight (g) of discharge | emission amount, the value of 1/5 1-3 times or less of the comparative example 1 is shown. From these results, the powder of the present invention can draw lines of almost the same density with a much smaller weight than the conventional white line powder, regardless of the structure of the line drawing machine of the present invention. It is useful as a powder.

It is the schematic which shows the aggregate particle and rod-shaped crystal which comprise the powder for white lines of this invention. It is the schematic which shows the manufacturing method of the powder for white wire | line derived from the newly constructed end materials of the waste gypsum board which is embodiment (1) of this invention. It is the schematic which shows the upper sieving process and the lower sieving process in the manufacturing method of the powder for white wire derived from the newly constructed end material of the waste gypsum board which is Embodiment (1) of this invention. 2 is a scanning electron micrograph of the whole image of the white line powder of Example 1. FIG. 2 is a scanning electron micrograph of an enlarged image of white line powder of Example 1. FIG. 3 is a scanning electron micrograph of the entire image of the white line powder of Comparative Example 1. FIG. 3 is a scanning electron micrograph of white line powder of Comparative Example 1. FIG. It is the photograph before the paper powder removal process of Example 1 and after the process. It is the photograph of the line drawn with the powder of Example 1, and the line drawn with the calcium carbonate powder of the conventional powder for line drawing. It is a photograph of paper powder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Crushing process 2 Waste gypsum board 3 Sieve 4 Fractionation process 5 Ground material 6 Paper powder removal process 7 Coarse sieving process 8 Upper sieving process 9, 10 Lower sieving process 11 Coarse sieving 12 Coarse powder 13 Coarse powder removing pulverized product 14 Upper sieving 14A Approximate center of upper sieve surface 15 Spiral movement 16 Heavy powder 17 Paper fluff 18 Partition 19 Exhaust port 20, 21 Lower sieve 22 White wire powder 23 Aggregated particles 24 Rod crystal 25 Void 26 Outer edge 27 End 28 Corner 29 Motor shaft C Center on sieve

Claims (5)

A powder obtained by removing a piece of paper and paper powder resulting from a base paper covering the waste gypsum board from a pulverized product generated by pulverizing a new end of waste gypsum board, wherein the powder has a width Aggregate particles having a diameter of 100 to 1000 μm and a particle density of 0.70 to 1.20 g / cm ³ in which rod-like crystals of 0.3 to 2.0 μm and a length of 1.0 to 10 μm are assembled. A white wire powder derived from waste gypsum board, characterized by comprising: 2. The white line powder derived from waste gypsum board according to claim 1 , wherein the aggregated particles are substantially spherical, and rod-like crystals protrude from the surface of the spherical body.   A pulverization step for pulverizing new building materials of waste gypsum board, a separation step for separating the pulverized product obtained in the pulverization step into a gypsum fraction and a paper piece, and the pulverized product that has passed through the separation step An upper sieving step in which aggregate particles of gypsum pass through a sieve having a vibration mechanism having a three-dimensional rotational motion such as horizontal, vertical, and inclined, and the paper powder of paper stays, and a lower part of the upper sieving step Aggregated particles of gypsum pass through a sieve having a vibration mechanism with three-dimensional rotational movements such as horizontal, vertical, and inclined with respect to the pulverized product that has been passed through the upper sieving process, and the paper powder of the paper A method for producing a white wire powder derived from waste gypsum board, comprising: 4. The method for producing a white wire powder derived from waste gypsum board according to claim 3, wherein the opening is 1000 to 250 [mu] m, and the upper and lower openings are the same, and the white wire powder is derived from waste gypsum board. Manufacturing method. In the manufacturing method of the powder for white lines derived from the waste gypsum board according to claim 3 , the mesh opening is 1000 to 250 µm, and the top and bottom multi-stage meshes are reduced toward the lower side. Manufacturing method of white wire powder.