JP3634717B2 - Manufacturing method of lightweight foam glass tile - Google Patents

Description

[0001]
[Field of industrial use]
The present invention relates to a lightweight foam glass tile using crushed used glass and a method for producing the same.
[0002]
[Prior art]
Conventionally, used glass bottles are roughly crushed and used again as cullet for the production of glass bottles. In many cases, however, 1.5 million tons are dumped in landfills every year due to the time required to collect, color sort and wash the bottles.
In addition, so-called Komi glass cullet that has been roughly crushed without color selection has begun to be used as a paving material that shines by mixing with an asphalt mixture, but it is still only a small part.
The ultra-light aggregate obtained by finely pulverizing Komi glass cullet is a fired body of 0.3 to 5 mm and is used for weight reduction of cement products and resin products. There is a limit to the amount used to maintain the heat resistance, sound absorption, etc., inheriting the properties of concrete and not so effective.
[0003]
In addition, in the conventional heat insulation method that has been widely used, organic heat insulating materials and heat insulating materials have drawbacks in flammability and water resistance, and condensation in the walls in summer is a problem.
Therefore, as disclosed in Japanese Examined Patent Publication No. 52-15603, a refractory inorganic material powder is used as a main aggregate, and a glass powder having a low melting point of 40% or less of an inorganic carbonate of 5% or less and a decomposition temperature of the inorganic carbonate or less. Mainly composed of 85% added, and after molding this, the inorganic carbonate is decomposed and fired to the extent that carbon dioxide gas for releasing foam is released. The law is known.
[0004]
Further, as disclosed in JP-A-7-267660, at least two kinds of silica powders containing 0.1 to 2% by weight of silicon nitride and having different silicon nitride contents are formed on the outer side of silicon nitride. Filled into a container made of a material that does not easily react with silica so that it has a low content and a high content of silicon nitride inside, it is heated at a temperature of 1700 ° C to 1850 ° C in an oxygen-free atmosphere, and foamed. A method for producing a foamed quartz glass structure is known.
[0005]
In general, when glass and dissimilar materials are mixed and fired, fine cracks are likely to occur due to the difference in thermal expansion. At this time, the generated fine cracks do not cause a problem in strength, but the water resistance is remarkably deteriorated. Destroyed by freezing expansion.
In addition, when glass powder of a single particle size that is not adjusted in particle size is freely foamed with calcium carbonate, the surface is covered with a dense layer, but the resulting shape foams into a dome shape with no corners different from the original shape. It cannot be used for tiles.
[0006]
[Problems to be solved by the invention]
In view of the above points, the present invention is a lightweight foam glass tile that has been made lighter by making effective use of used glass, and the shape after foaming is sharp like a tile, leaving excellent free foaming. It is to provide a lightweight foam glass tile manufacturing method that can obtain a smooth surface.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, lightweight foam glass tile manufacturing method of the present invention, the average particle size 14μ fines weight mixing ratio between the average particle size 50μ grit glass milled 35: 5-25: 15 and As a foaming agent, calcium carbonate having a weight of 1.0 to 2.0% by weight of the glass powder is used as a foaming agent, and a kneaded product is formed by adding 15% of water to the weight of the glass powder. The kneaded product is 400 kg / cm 2 without drying . It is molded by pressure and heated at 750 to 800 ° C. for 30 minutes for foaming.
[0008]
Hereinafter, the present invention will be described in detail.
The present invention mixes well with inorganic salts that can generate harmless decomposition gas at the melting temperature of glass, such as calcium carbonate, mainly from pulverized used glass, and then press-molds water into a required shape and then fires it. Causes the glass to soften and melt, and then the inorganic salt added as a foaming agent reacts with the glass or decomposes to generate carbon dioxide within a short time and become trapped in the surrounding molten glass, forming a foam. .
[0009]
The mechanical strength of the foam is higher for fine bubbles, and it is desirable that the temperature conditions be such that gas is generated in a short time.
Furthermore, the foaming shape can be made similar to the shape at the time of molding by controlling the gap formed by the glass powder.
[0010]
The glass raw material used in the present invention is preferably a glass having a single composition and may be of any origin or color, but it is necessary to avoid contamination of foreign matters such as paper and metal as a cause of defects and coloring as much as possible.
Therefore, it is desirable that the contact portion with the glass of the coarse pulverization or fine pulverization machine is not metallic.
[0011]
A ball mill is used for fine pulverization, and coarse and fine particles are obtained depending on the pulverization time. The coarse particles are 45% or more 55% and the average particle size is 50μ, and the fine particles 45μ or more are 25% and the average particle size is 14μ. Grind as follows.
The combination of coarse and fine particles is 35: 5 to 25:15, preferably 30:10, by weight.
[0012]
The calcium carbonate is added as a foaming agent, but the purity may be industrial or a reagent, but the foaming amount varies greatly depending on the particle diameter, so that a fixed size is desirable.
When the average particle size of calcium carbonate is 30 μm, the amount of foaming is small, and when 1 μm, the amount of foaming is too much and the strength is lowered. Therefore, the calcium carbonate used preferably has an average particle size of 15 μm.
The amount of the blowing agent is 1.0 to 2.0 parts, preferably 1.5 parts, per 100 parts of the glass powder.
[0013]
Predetermined calcium carbonate is added to 100 parts of glass powder and mixed mechanically uniformly, and then 15 parts of water is added as a binder and kneaded well to form a kneaded product.
It is sufficient that the water content does not collapse even if the kneaded product is held in hand, and the water content is not particular to 15 parts.
[0014]
Although the relationship between the molding pressure and the bulk density of the fired body is thin, the kneaded product is filled in a mold and molded at a pressure of 400 to 600 kg / cm 2 to form a molded body.
The molded body is fired immediately after being molded without being dried.
[0015]
Firing is performed using an electric furnace in which the distance from the heating element is made uniform in order to obtain uniform foaming, and the molded body placed on the alumina plate on which the alumina powder is dispersed is heated at a heating rate of 700 ° C. at 400 ° C./hour. And heated for 20 minutes, further heated to 750 ° C. and held for 30 minutes for foaming.
Thereafter, the power was turned off and the system was cooled down to room temperature in the furnace.
In addition, in the case of continuous firing, it is possible to perform continuous firing by inserting directly into the preheating zone set at 700 ° C. and moving three blocks of the firing zone and slow cooling zone set at 750 ° C. over time. it can.
[0016]
The foam obtained by baking has a shape of closed cells with a sharp corner covered with a flat surface, a bulk density of 0.4 to 0.7 g / cm 3 and a closed cell of 100 to 200 μm, and the surface is a dense layer. Covered.
[0017]
The thermal conductivity of this foam measured by Kyoto Electronics Kemtherm QTM-D3 is (λ) = 0.07 to 0.08 Kcal / mh ° C. (293 to 335 J / mh ° C.). The thermal conductivity of the tile was 1.232 Kcal / mh ° C.
Moreover, when the temperature rise of the sample surface due to the heat of a 25 W light bulb was observed from the back of the sample in a thermostatic chamber, it stabilized in about 50 minutes, becoming + 23 ° C for a general porcelain tile and + 8 ° C for this foam. The foam showed good thermal insulation.
[0018]
【Example】
Next, examples of the present invention will be described in detail, but the present invention is not limited thereto.
Example Glass powder (coarse) 66 parts Glass powder (fine granules) 22 parts Calcium carbonate 1.32 parts Water 13.2 parts After crushing the discarded glass for liquid crystal, it is finely pulverized with a ball mill. Two types of powders were prepared.
These average particle diameters were 50 μ and 14 μ, respectively.
66 parts and 22 parts of each of these two kinds of glass powders were mixed well with 1.32 parts of calcium carbonate, and further, 13.2 parts of water was added and the kneaded material was uniformly filled into a forming die, and the press pressure was 400 kg / cm 2. To form a molded body of 60 mm × 60 mm × 19 mm.
Gently remove the compact from the die and place it on an alumina tray on which alumina powder has been sprinkled, fire it from room temperature to 700 ° C at a heating rate of 400 ° C per hour in an electric furnace, hold for 20 minutes, and further raise the temperature to 750 ° C When kept for 30 minutes, foaming rapidly occurred.
As it was cooled in the furnace to room temperature, a lightweight foam glass tile having a shell structure composed of a single composition glass having a dense surface and having closed cells inside was obtained.
[0019]
The size was 95 mm × 95 mm × 24 mm covered with a flat surface, the specific gravity was 0.4, and the bending strength was 200 N / cm 2.
The surface was covered with a glossy dense hard layer and no water absorption was observed.
The inside of the fired body was uniformly filled with fine independent bubbles having a diameter of about 0.2 mm.
[0020]
【effect】
The present invention compensates for the disadvantages of conventional methods by making effective use of used glass and reducing the weight of the foamed glass tile, and has excellent heat resistance and sound absorption, and has excellent mechanical strength and water resistance. It can be.
By providing the outer wall insulation material of the building structure that replaces the conventional internal heat insulation method due to the excellent water resistance due to the dense surface and especially the heat insulation property due to the bubble structure, the sensible heat of the frame can be used, resulting in a change in indoor temperature The energy saving effect is expected as what can be minimized.
In the process of making a single composition glass into a powder, the present invention combines large particles and small particles in a certain ratio, so that a sintered body having a sharp and smooth surface with a constant shape is always obtained. A lightweight foamed glass tile composed of 0.2 mm of uniform closed cells is obtained which is lightweight, heat-insulating and excellent in shape.
In other words, by adjusting the particle size of the glass powder of the same composition, a flat surface with sharp corners foamed similar to the original shape can be obtained without restriction by the mold, and it is covered with a dense surface layer unique to free foaming. A lightweight foam glass tile is obtained.

Claims (1)

The average particle size 50μ coarse particles and the average particle size 14μ fines mixing weight ratio of the milled glass 35: 5-25: as a 15, and 1.0 to 2.0 weight percent calcium carbonate of the glass powder by weight and a blowing agent In addition, 15% of the glass powder weight water is added to form a kneaded product, the kneaded product is molded at a pressure of 400 kg / cm 2 without drying, and heated at 750 to 800 ° C. for 30 minutes to be foamed. production how of lightweight foam glass style to.