JP2000061924A - Manufacture of inorganic plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve surface formation and to make the surface smooth in a circulating plate-making process wherein a recycle material is used. SOLUTION: In a manufacturing method according to this circulating plate- making process, a recycle material 2 is mixed in a cement material 3 and a fibrous material 1 so as to make a plate. In this case, the fibrous material 1 split by a pulper 11 is subjected to a treatment of wet type maceration 13 in the middle of a route for sending it, while the recycle material 2 is crushed 21 to be the powder of the maximum particle size 0.2-0.5 mm, and then the slurry of the fibrous material subjected to the wet type maceration and the powder of the recycle material are mixed with the cement material 3. Subsequently, the mixed slurry is passed through a slurry screen 43 of a 2-3 mm mesh to remove foreign substances and then the plate is made from the mixed slurry.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an inorganic plate. More specifically, the invention of this application relates to a method for producing an inorganic plate by an improved reflux papermaking method, which has a good surface texture even after press molding. 2. Description of the Related Art Conventionally, as a method for producing an inorganic building material such as a tile or an outer wall material, an aqueous slurry of a cement raw material is formed, and then dewatering press molding and curing are performed to produce an inorganic plate. Papermaking methods are known. Also, with this method,
A cement-based raw material such as cement, silica sand, and fly ash is mixed with a reinforcing fiber material such as pulp or rock wool to form an aqueous slurry.
Attempts have been made to mix scraps and cuttings generated in the papermaking and pressing processes or product wastes after curing as recycled materials and reuse them for papermaking. [0003] The use of such recycled materials is considered to be desirable in terms of reducing raw material costs and avoiding increased waste. [0004] However, in the production of an inorganic plate by a recirculation-type papermaking method in which a recycled material is mixed, the surface of an original sheet after the papermaking is severely uneven.
There is a problem that the surface finish after dehydration press molding is affected, and the surface formation is actually unfavorable. For the production of inorganic plates other than the papermaking method,
Various proposals have been made for pulverizing and using recycled materials, or for fibrillating fibers such as pulp.However, handling of recycled materials in the production of inorganic plates by papermaking and surface texture So far, there are no desirable proposals for improvement measures, and it is still an unsolved problem. Therefore, the invention of the present application solves the above-mentioned problems and improves the surface formation after papermaking and dewatering press molding in the production of an inorganic plate by a recirculation papermaking method in which recycled materials are reused. It is characterized by providing a new method that can achieve. Means for Solving the Problems [0007] The invention of this application is to solve the above-mentioned problems, and to provide an inorganic plate by a recirculation type paper-making method in which a recycled material is mixed with a cement raw material and a fiber material to form a paper. A manufacturing method, in which a pulper defibrated fiber material is wet defibrated in the middle of a liquid feeding path, and the recycled material is pulverized into a powder having a maximum particle size of 0.2 to 0.5 mm. The slurry of the recycled fiber material and the powder of the recycled material are mixed with the cement-based material,
Then, the mixed slurry is passed through a slurry screen having a mesh size of 2 to 3 mm to remove foreign substances, and then papermaking is performed from the mixed slurry. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention of this application has the features as described above, and the embodiments thereof will be described in detail below. In the production method of the present invention,
The process itself of producing a raw sheet (green sheet) by papermaking from an aqueous slurry, followed by dehydration press molding, and curing by an autoclave or the like can be considered in the same manner as in the past. And, for the solid raw material component for constituting the aqueous slurry, cement-based raw material comprising an inorganic compounding material including silicate-based material such as portland cement and silica sand, fly ash, etc. In addition, a fiber material made of natural or synthetic reinforcing short fibers such as pulp or rock wool is considered. In the production method of the present invention,
In addition to these conventional solid components, recycled materials are used. This recycled material is scrap chips generated in the papermaking process, cutting chips generated in the dewatering press process, or product waste after curing. When the recycled material is mixed with the aqueous slurry to form a paper, the requirements described above are adopted in the present invention in order to improve the formation. That is, it is as follows. <A> The pulper defibrated fiber material is subjected to wet defibration treatment in the middle of the liquid feeding path, and then mixed with a cement-based raw material and a recycled material. <B> The maximum particle size of the recycled material is 0.2 to 0.5 mm.
And then mixed with a cement-based raw material and a fiber material. <C> The aqueous slurry obtained by mixing the cement-based raw material, the fiber material, and the powder of the recycled material is passed through a 2-3 mm mesh slurry screen to remove foreign substances.
Papermaking from aqueous slurry. The wet fibrillation <A> in the middle of the liquid feeding is performed while the fiber forming the aqueous slurry is used as the liquid phase and the fiber is fed to the mixing area of the cement raw material and the recycled material.
Accordingly, the disintegration is performed by a wet disintegrator such as an extrusion screw type. The treatment of the present invention is indispensable when dry pulper defibration or wet storage is performed before the pulp is mixed with the cement raw material after defibration. The reason is as follows. The defibrating ability of short fibers such as pulp is determined by a pulper (fibrillating machine), and defibrating cannot be performed beyond a certain ability. Further, even if wet defibration is performed, if it is stored before being mixed with an aqueous slurry for papermaking, agglomeration of fibers is generated due to secondary aggregation. For this reason, agglomeration of fibers such as pulp lumps will not be eliminated, and this has caused formation failure during papermaking. Therefore, in the present invention, the fibers are loosened by further wet disaggregation (defibrillation refiner) treatment during the liquid feeding for mixing with the aqueous slurry for papermaking, thereby eliminating fiber agglomeration and smoothing the surface formation. And [0011] After the wet disintegration treatment of the present invention is performed, the mixture is sent to an area where an aqueous slurry is formed by mixing with a cement raw material and a recycled material without being stored. Regarding the crushing of recycled materials <B>,
As described above, it is essential that the maximum particle size is in the range of 0.2 to 0.5 mm. By setting the content in this range, the surface of the raw sheet after papermaking is not noticeably scattered, and in dewatering press molding, the powder present on the surface penetrates into the inside of the sheet, so that the surface smoothness is improved. Will be done. When the maximum particle size is less than 0.2 mm, the burden on the pulverizing step increases, and it does not contribute much to the improvement of the surface texture, so that it is not economical.
On the other hand, if it exceeds 0.5 mm, the surface texture visually deteriorates. In addition, clogging occurs in the passage <C> of the slurry screen. In addition to the fiber material, the inorganic compound material or the cement agglomerate is apt to be entangled with the recycled powder, and from the viewpoint that these may impair the surface formation, the above-mentioned 0.2 to 0.2. A range of maximum particle size of 5 mm is essential. Furthermore, the passage <C> of the slurry screen of the present invention is indispensable for removing foreign substances for improving the surface texture. Mesh (opening) is 2-3
mm is optimal. If the size is smaller than this, clogging frequently occurs, and it is not always preferable for the properties of the raw sheet after papermaking. If it exceeds 3 mm, the effect of formation improvement will decrease. It is important to note that in the production of an inorganic plate by the reflux papermaking method, <A> wet disaggregation in the middle of liquid feeding as described above <B> to a maximum particle size of 0.2 to 0.5 mm Crushing of Recycled Material <C> The requirement for passing through a 2-3 mm mesh slurry screen is that any one lacking does not actually contribute to the improvement of surface texture. Here, “practical” means “in the evaluation as a practical product”. The mixing ratio for papermaking is as follows:
The powder of the recycled material is desirably 15% by weight or less relative to the total solid content weight. It is more preferably at most 12% by weight. And cement is
30-70% by weight, other inorganic compounding materials such as silica sand are 5-2
A standard of 0% by weight and a fiber material of 10% by weight or less can be used as a standard. When the solid slurry is used as an aqueous slurry, 30 to 80% of the total slurry weight can be considered as the water content. The papermaking may be performed by any method such as a round net or a long net, and dehydration press molding and curing may be performed in the same manner as in the related art. There is no particular limitation. FIG. 1 of the accompanying drawings illustrates, by way of example, the configuration of a process for implementing the method of the present invention.
For example, as shown in FIG. 1, a fibrous material (1) such as pulp is sent to a storage chest (12) by a pump after being defibrated by a pulp (11). The fibrous material mixed with water is subjected to wet disintegration by a disintegrator (13) in the middle of a liquid feeding path supplied for forming an aqueous mixed slurry for papermaking (4) in a mixing tank (41). At this time, the amount of water for sending the liquid may correspond to the whole amount of water for forming the aqueous mixed slurry (4), or may be a part thereof. However, in order for the wet disintegration process to be effective, the amount of water for the fiber material in the disintegrator (13) must be at least 5 times.
Double weight, more preferably 10 times weight.
On the other hand, the recycled material (2) is pulverized in a pulverizer (21) so that the powder has a maximum particle size of 0.2 to 0.5 mm. Next, the pulverized recycled powder is put into the mixing tank (41) via the tank (22) and the measuring hopper (23). Further, the cement-based raw material (3) is mixed in advance or separately, and the measuring hopper (31)
After the measurement, a predetermined amount is put into the mixing tank (41). The aqueous mixed slurry (4) mixed in the mixing tank (41) contains a fiber material and a recycled material together with the cement-based raw material. The produced aqueous mixed slurry (4) is then sent to a slurry screen (43) of the present invention via a storage chest (42), and foreign substances are removed when passing through the slurry screen (43). Thereafter, the aqueous mixed slurry (4) is
The paper is sent from the head box (44) to the inlet box (51) of the paper machine (5), where the paper is made. Although not shown, the raw sheet thus formed is dewatered and pressed and cured by an autoclave or the like to become a product inorganic plate. For example, the results of evaluating the improvement of the surface ground by the method of the present invention with the above process configuration are as follows, for example. [Table 1] As described in detail above, according to the invention of this application, the recycled material is utilized in the reflux papermaking method, and the surface formation after press molding is excellent and the smoothness is excellent. It will be.

[Brief description of the drawings] FIG. 1 is a diagram illustrating a process configuration of the present invention. [Explanation of symbols] 1 Textile materials 2 Recycled materials 3 Cement-based raw materials 4 Aqueous mixed slurry 5 Papermaking machine 11 Pulper 12 storage chest 13 Disintegrator 21 crusher 22 tank 23 Weighing hopper 41 Mixing tank 42 storage chest 43 Slurry screen 44 Head Box 51 Inlet box

Continuation of front page    F-term (reference) 4G012 PA18 PA24 PA27 PA35 PE01                       PE04                 4G052 GA02 GA14 GA17 GA25 GA26                       GB81 GC02 GC06                 4G055 AA02 AA10 AB05 AC01 CA02                       FA09                 4L055 AA11 BA01 BA11 BB04 BF01                       BG04 EA15 EA16 FA09 FA14                       GA24

Claims (1)

Claims: 1. A method for producing an inorganic plate by reflux-type paper-making in which a recycled material is mixed with a cement-based raw material and a fiber material, and the pulper-fibrillated fiber material is fed. After the wet disintegration treatment in the middle of the route, the recycle material is pulverized into powder having a maximum particle size of 0.2 to 0.5 mm, and the wet disintegrated fiber material slurry and the recycle material powder are mixed with cement-based material. And then passing the mixed slurry through a slurry screen of 2 to 3 mm mesh to remove foreign substances, and then paper-making the mixed slurry.