JPH048503A - Manufacture of inorganic foam and firing furnace to be used for that - Google Patents

Abstract

PURPOSE:To manufacture continuously an inorganic foam of raw materials by one time firing, by a method wherein an inorganic, foamable and granulated matter provided in a stratified state on a heat-resistant conveyor belt is foamed by heating and press molding is performed by passing the same through between molding rolls and the inorganic foam molded into a crest-shaped sate is cooled. CONSTITUTION:A conveyor belt 1 is run by a driving roll 2 and a hopper 3 feeds an inorganic granulated matter on a conveyor belt 1. A preheating zone, foaming zone, rapid cooling zone, heating and molding zone, gradual cooling zone and cooling zone are formed within a firing furnace K. The inorganic, foamable and granulated matter sent to the foaming zone through the preheating zone is temperature-raised by a burner 5, foamed, cooled at the quick cooling zone, lowering surface layer is solidified, contracted and peeled off from the conveyor belt 1. A temperature within a heating and molding zone is held at about 750 deg.C by the burner 5. An inorganic foam 4 is conveyed by a counterlike rotary roll 9, a form where both ends are dangled is pressented, pressed and molded between the molding rolls 10, which is cooled for prevention of adhesion. The inorganic foam 4 cooled gradually uniformly at the gradual cooling zone, then entered into the cooling zone and moved on a roll 8 to an outlet of the firing furnace K.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing an inorganic foam and a firing furnace used therein. More specifically, we will discuss a method for manufacturing inorganic foam that can continuously manufacture accessories made of inorganic foam with a decorative surface, such as the protruding corners and large corners of buildings, from raw materials in a single firing process. This article relates to a firing furnace used for this purpose.

[Conventional technology and problems to be solved by the invention] Inorganic foams are lightweight and easy to handle, and have excellent heat retention, fire resistance, and durability, so they have been increasingly used in prefabricated houses in recent years. be.

Such an inorganic foam can be easily manufactured by laminating an inorganic granulated foam raw material on a refractory and heat-resistant conveyor belt installed in a furnace, and heating and foaming the raw material.

On the other hand, when actually constructing a house or the like using inorganic foam, there are large corners and projecting corners, so abbreviated-shaped members called so-called corner accessories are required. In the construction of buildings, it is preferable to use corner accessories made of members of the same quality as wall materials, but it has been very difficult to continuously manufacture corner accessories from granulated raw materials. That is,
In the past, for example, corner accessories were created by cutting a flat plate that had been fired to a certain degree, placing the two flat plates in a mold made of refractory material, reheating them, and utilizing the softening and bending of the foam board. (See Japanese Patent Application No. 2-63772), since the foam board is fired twice and is a highly insulating material, heat cannot be uniformly transferred during reheating. For this reason, cracks occur during the heating process, and in order to prevent this, the heating rate must be slowed down. As a result, there is a problem that a large amount of time is lost.

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, an object of the present invention is to provide a method for producing an inorganic foam that can continuously produce corner accessories from raw materials by firing at -degrees, and a firing furnace used therein.

[Means for Solving the Three Problems] The method for producing an inorganic foam of the present invention is a method for producing an inorganic foam by heating and cooling an inorganic foamable granule on a heat-resistant conveyor belt running in a furnace. A step of heating and foaming the inorganic foamable granules provided in a layer on the heat-resistant conveyance belt, and passing the inorganic foam between forming rolls consisting of an upper concave roll and a lower convex roll. The method is characterized by comprising a step of press-molding the inorganic foam formed into a mountain shape, and a step of cooling the inorganic foam formed into a mountain shape. Furthermore, the firing furnace of the present invention is a continuous firing furnace that manufactures an inorganic foam by heating and cooling an inorganic foam granule on a heat-resistant conveyor belt running inside the furnace, It is characterized in that forming rolls consisting of an upper concave roll and a lower convex roll are provided downstream of the heating zone for heating and foaming the granules.

[Example] Hereinafter, a method for producing an inorganic foam according to the present invention and a firing furnace used therein will be explained based on the accompanying drawings.

FIG. 1 is an explanatory longitudinal cross-sectional view of one embodiment of the firing furnace of the present invention.

In Fig. 1, (1) is a heat-resistant endless conveyor belt installed in the firing furnace (K), which is made of heat-resistant materials such as stainless steel mesh belt, steel belt, and ceramic net. is used. The conveyor belt (1) is driven by drive rolls (2).

A supply hopper (3) is provided above the conveyance zone (1) in front of the firing furnace fK) for supplying inorganic granules that are fired and foamed by heating onto the conveyance zone (1).

The inorganic granules are generally made of M203-8i02 minerals such as acid clay, shirasu, nacre, anti-flintstone, and feldspar, and in addition, soda ash, sodium nitrate, glass powder,
Granules obtained by granulating supplementary materials such as a fluxing agent such as boric acid and borax, and a blowing agent such as dolomite, SiC, barium carbonate, and potassium carbonate are used. In addition, powder raw materials for the surface decorative layer formed on the base layer include:
For example, a glaze made of glassy powder such as frit or feldspar is pulverized to a particle size of about 0.5 to 2.01 using a pan-type granulator or the like. Supply hopper (3)
The number may be appropriately selected depending on the number of layers of the inorganic foam (4). Although not shown, a metal net or the like may be embedded in the inorganic granules for reinforcement.

Heating burners (5) are provided at appropriate intervals on the side wall of the firing furnace (K).

A preheating zone, a foaming zone, a quenching zone, a heating forming zone, a slow cooling zone, and a cooling zone are formed in the firing furnace (K) according to this embodiment.

The preheating zone is a zone where water and organic matter in the raw material are removed by heating, and is heated to approximately 350 to 580°C, although it varies depending on the type of raw material, charge thickness, etc.

The inorganic foamable granules sent to the foaming zone through the preheating zone are successively heated by a burner (5) and foamed. The heating temperature varies depending on the type and composition of raw materials, but is generally raised to 880°C.

In this embodiment, a quenching zone is provided immediately after the foaming zone.

The purpose of the conventional quenching zone was to speed up the firing speed and shorten the furnace length by rapidly cooling the foamed plate in the high-temperature foaming zone to the solidification temperature range, but in this example, the quenching zone was used as a conveyor zone ( The purpose is to make it easier to separate the inorganic foam (4) from 1). That is, the inorganic foam (4) that has been heated to a high temperature and foamed on the conveyor belt (1) is in close contact with the conveyor belt (1) via a mold release material such as alumina oxide, but by rapidly cooling it after foaming, As the temperature decreases, the surface layer of the inorganic foam (4) solidifies and contracts, thereby peeling off from the conveyor belt (1). As a result, inorganic foam (
4) and the conveyor belt (1) can be easily and reliably separated. In the quenching step, the temperature of the conveying zone (1) and the inorganic foam (4) are controlled to effectively achieve the above purpose.
The back side temperature is 600~690℃ and 620~
It is preferable to control the temperature to 720°C.

The temperature setting of the rapid cooling zone varies depending on the compounded material, but is usually 65
Since the solidification and shrinkage temperature of the raw material is around 0°C, the ambient temperature is preferably as low as about 820°C. Specifically, an air supply port (6) is formed in the artificial part of the rapid cooling zone, and rapid cooling can be performed by supplying cold air of about 30° C. through this air supply port (6). (7') is an exhaust port for sucking the cold air blown into the quenching zone to prevent it from entering the firing zone or heating zone.

The inorganic foam (4) separated from the conveying zone (1) in the quenching zone is sent to the thermoforming zone. The temperature within the hot forming zone is maintained at approximately 750°C by a burner (5). In the quenching zone, the inorganic foam (4) is conveyed by a pipe-shaped roll (8), but in the heated molded product, it is conveyed by a solo bread-shaped rotating roll (9). Since the inorganic foam (4) is conveyed so that its center is at the top of the rotating roll (9), the inorganic foam (4) is conveyed while being conveyed.
) reaches a softening point as the temperature is increased one after another, and both ends begin to droop and take on an almost predetermined shape. However, since the board thickness and surface condition are not adjusted, the material is pressed and molded into the shape of the desired accessory by passing it between cooling molding rolls to prevent adhesion. The forming roll (roller) is the third
As shown in the figure, it is composed of an upper concave roll (10a) and a lower convex roll (10b), and has a structure in which water or air circulates inside. The shape and size of the forming roll may be appropriately selected according to the shape and size of the corner accessory, and are not particularly limited in the present invention. From the viewpoint of preventing adhesion, it is preferable to control the surface temperature of the forming roll 001 to be 40 to 100° C. lower than the surface temperature of the inorganic foam (4).

The pressure-molded inorganic foam (4) is sent to the slow cooling zone on a rotating roll (9) shaped like a Solopan ball (see Figure 4).
Here, it is uniformly cooled down. The temperature of the gradual cooling zone is 58 near the entrance.
The temperature is about 0°C, and the temperature near the exit is set to about 400°C.

The inorganic foam (4) then enters the cooling zone and moves on the pipe-shaped rolls (8) towards the exit of the kiln (K) (see Figure 5). During this time, the inorganic foam (4) is cooled down to about 400 to 60°C while drawing a gentle downward curve, and then transported out of the furnace.

The inorganic foam (4) carried out of the furnace is cut to an appropriate length, and both sleeves are also cut to a predetermined width.

By manufacturing according to the method described above, it is possible to continuously form a corner accessory whose design is exactly the same as that of a flat plate from the granulation raw material. When such a corner accessory is installed in a building, its aesthetic appearance creates an atmosphere (a sense of continuity or unity) that cannot be seen in conventional buildings.

Hereinafter, the method for producing an inorganic foam of the present invention will be explained based on Examples, but the present invention is not limited to these Examples.

Example Preparation of base layer raw materials Oya stone 64.5% (weight %, same hereinafter), soda ash 18
%, water glass powder 5%, royal talc 12% and 5jC0
, 5% was put into a ball mill together with 1 Ommφ steel balls and dry-milled for 7 hours. The particle size of the powder obtained was 44μ96%. This powder was granulated using a pan-type granulator while spraying a 1526 molasses solution (a solution in which 15% molasses was dissolved in water). The moisture content of the obtained granules was 15%, but after drying in an external heating rotary kiln to a moisture content of 3%, the particle size was 2.5%.
It was sieved to be in the range of ~1.0 rA/rA.

Preparation of raw materials for decorative layer A blend of raw materials consisting of 53% glass powder, 37% R-2 frit (glaze made by Kasai Glaze), 3% atomized clay, 296 bentonite, and 5% zircon was mixed with alumina balls of 10 to 30 m + *φ. The mixture was placed in a ball mill and dry ground for 10 hours. The particle size of the obtained powder is 44μ9696
Met. Using a pan-type granulator, this powder was mixed with a binder (1 p of water, 0.4% potassium water glass and Monard Gum DA).
(Kelsan manufactured by Dainippon Pharmaceutical ■. "Kelsan" is a type of binder) 2% solution) was granulated while being sprayed. The moisture content of the obtained granules was 12%.

The obtained granulation raw material was placed in a closed container, and carbon dioxide gas was introduced into the container to instantaneously harden the material, and then it was sieved to have a particle size in the range of 1.5 to 3.0 nm. This granulated raw material was further placed in a pan-type granulator and while being transferred, the coloring raw material liquid described below was sprayed to obtain a cosmetic raw material.

Coloring of the cosmetic layer raw powder 10i of the cosmetic layer raw powder, Y-11 (pigment manufactured by Nichikyaku Sangyo ■) Ig, water 70g 1 Monard gum (Kelsan manufactured by Dainippon Pharmaceutical ■) O, 1g and potassium water glass (Kelsan manufactured by Nippon Kagaku ■) ) 20g with a mixer to make a coloring raw material, and add the granules for the decorative layer (particle size: 1.5 to 3.On+/
w) Colored wrinkled grains A were prepared by spraying 200 cc of colored raw material liquid A onto ID.

Similarly, 100 g of the powdered raw material for the makeup layer, 3 g of J-24 (pigment manufactured by Nichikyaku Sangyo ■), 70 g of water, 0.1 g of Monard gum (Kelzan manufactured by Dainippon Pharmaceutical Aji), and 20 g of potassium water glass (Kelzan manufactured by Nippon Kagaku ■) were mixed in a mixer. to make coloring raw material liquid B, and add the granules for the decorative layer (particle size 1.5 to 3.0).
Colored wrinkled grains B were prepared by spraying 100 cc of colored raw material liquid B onto i/m) IM.

Next, 65% by volume of coloring raw material grains A, 15% by volume of coloring raw material grains B, and 96% by volume of the aforementioned cosmetic raw material granules were placed in a rocking mixer and mixed for 3 minutes to obtain a makeup layer raw material.

An inorganic foam was manufactured using the base layer raw material and decorative layer raw material prepared as described above.

A firing furnace with a length of 39 m, equipped with a quenching zone and a heating forming zone, and a heat-resistant mesh belt for conveyance installed inside.
Net speed: 15ctIl/min) was used.

While inserting a lath mesh cut to a width of 351 into a 15 mu hollow above the heat-resistant mesh belt, the base layer raw material was charged to a thickness of 30 mm from a supply hopper.

Next, the raw material for the decorative layer is supplied to a thickness of 5! from the other supply hoppers.
I charged it on the base layer to make it 111.

The obtained laminate was transported to a preheating zone controlled at 350 to 580''C to remove water and organic matter from the raw materials.

Next, move to the foaming zone and bring the temperature inside the furnace to 6o.

The temperature was raised sequentially from °C to 880 °C. This foam zone had burners attached to the upper and lower tiers, and the combustion space was divided into upper and lower sections by mesh belts and refractory materials. For this reason, the upper and lower combustion spaces were set to draw different temperature rise curves, and after the base layer was welded and foamed, the decorative layer raw material was melted and vitrified after a delay, and the two layers were integrated.

When the inorganic foam leaves the foaming zone and enters the quenching zone, it is in a soft state, but as it is rapidly cooled in the quenching zone, its outer periphery hardens, becomes hot and begins to shrink. At that time, the temperature of the mesh belt is lower than that of the inorganic foam zone, and the foam and mesh belt easily separate from each other due to contraction of the foam and contraction of the mesh belt.
The foam whose surface had been solidified in this way was sent to the next hot forming zone by the rotation of the rolls. The temperature of the rapid cooling zone was 640°C.

The heated molded body was heated by upper and lower burners, and the temperature inside the furnace was 750°C. The foam sent from the quenching zone was gradually heated up as it traveled on a rotating roll of heat-resistant steel in the shape of a solo bread ball with a 20R tip, and the foam hung from the end. Then, with the foam in contact with almost the entire surface of the rolled solo bread ball,
The convex portions and concave portions were processed into a 2OR shape, and the sample was guided between forming rolls made of heat-resistant steel that was internally cooled with water and air (surface temperature: 620° C.). The forming roll has a roll spacing of 35
mm, and the foam was pressed and molded by an upper concave roll and a lower convex roll, and the surface was solidified.

The foam was then transferred to a slow cooling zone on a Solopan bead-shaped receiving roll, where it was uniformly cooled. The temperature in the slow cooling zone gradually decreased from 580'C to 400°C.

Next, the foam entered a cooling zone at 400°C, was cooled down to 60''C in a gentle downward curve, and was transported out of the furnace.

The foam that came out of the furnace mouth was cut to a length of 200 (1), and then cut to a width of 150,111 mm on one side to produce an L-shaped corner accessory.

The resulting L-shaped corner accessory was made of flat inorganic foam, and the surface decoration was completely unchanged.When struck, it made the sound of porcelain, and was able to be moved around the exterior wall corner, which was lightweight and had a calm texture.

[Effects of the Invention] As explained above, according to the production method of the present invention, L-shaped corners of the same quality as a flat plate can be continuously produced from inorganic granules in one firing.

(5): Burner (8): Pipe roll (9) Double rotation roll Oo): Forming roll

[Brief explanation of drawings]

Fig. 1 is an explanatory longitudinal cross-sectional view of one embodiment of the firing furnace of the present invention, Fig. 2 is a cross-sectional view of the prison line in Fig. 1, and Fig. 3 is a cross-sectional view taken along the line (B)-EJ in Fig. 1. , Figure 4 is (C) − of Figure 1.
5 is a sectional view taken along the line (D)-[DJ in FIG. 1. (Main symbols in the drawing) (K): Firing furnace (1), endless conveyor belt (3): Supply hopper (4): Inorganic foam patent applicant National Housing Industry Co., Ltd. −−);〒;−e

Claims (1)

[Claims] 1. A method for producing an inorganic foam by heating and cooling an inorganic foamable granule on a heat-resistant conveyor belt running in a furnace, the method comprising:
A step of heating and foaming the inorganic foamable granules provided in a layer on the heat-resistant conveyance belt, and pressing the inorganic foam by passing it between forming rolls consisting of an upper concave roll and a lower convex roll. 1. A method for producing an inorganic foam, comprising a step of cooling an inorganic foam formed into a mountain shape. 2. After the foaming step, there is a step of rapidly cooling the inorganic foam to facilitate separation from the heat-resistant conveyor belt, and a step of reheating the cooled inorganic foam that has been separated from the heat-resistant conveyor belt. The manufacturing method according to claim 1. 3. The manufacturing method according to claim 2, wherein in the quenching step, the temperature of the heat-resistant conveying belt and the back surface temperature of the inorganic foam are controlled to be 600 to 690°C and 620 to 700°C, respectively. 4. The manufacturing method according to claim 2, wherein the surface temperature of the forming roll is controlled by water or air so that it is 40 to 100°C lower than the surface temperature of the inorganic foam with which the roll comes into contact. 5. A continuous firing furnace for producing an inorganic foam by heating and cooling an inorganic foamable granule on a heat-resistant conveyor belt running in the furnace, the heating zone for heating and foaming the inorganic foamable granule. A firing furnace characterized in that a forming roll consisting of an upper concave roll and a lower convex roll is provided on the downstream side of the kiln. 6. Claim 5, wherein the surface temperature of the forming roll is controlled by water or air so that it is 40 to 100°C lower than the surface temperature of the inorganic foam with which the roll comes into contact.
The firing furnace described.