Blocks for recycling rock wool waste and recycling method

Abstract

To provide a technology (block for use in regenerating and regenerating method thereof) for regenerating a rock wool waste material, which allows it to be put into a melting furnace as a raw material for producing a rock wool even when the rock wool waste material is composed of a rock wool waste material fiberized insufficiently on production of the rock wool or dust collected by a dust collector; to provide a block for regenerating a rock wool waste material having a low moisture content of 0.5% or less and a high compressive strength of 1.0 N / mm2 or more; and to provide a regenerating method of a rock wool waste material which allows the rock wool waste material to be continuously regenerated in a large amount as a rock wool use.MEANS: A block for use in regeneration of a rock wool waste material contains a rock wool waste material having a specific untamped density, a specific ratio of cement, and a specific ratio of water.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a block for recycling waste rock wool. In particular, the present invention relates to a block for feeding into a melting furnace to recycle waste rock wool. The present invention also relates to a method for recycling waste rock wool. [Background technology]

[0002] A fiber layer made of mineral fibers such as rock wool is widely used on the surface of structures to provide fire resistance, fire prevention, sound absorption, and / or thermal insulation. Rock wool is a mineral fiber made by rapidly cooling materials, primarily consisting of rock or blast furnace slag, melted in a melting furnace. During fiberization, some of the material is insufficiently fiberized (including partially or completely granular, powdery, or broken, short fibers; the same applies below), making it unusable as a product. Furthermore, when the raw materials are melted, some of the raw materials are emitted as dust along with the exhaust gas and collected by a dust collector. Some of the waste generated during the production of rock wool is used as a raw material in cement production, but is disposed of as industrial waste.

[0003] Rock wool molded products are made by adding resin to rock wool and forming it into plates, blocks, or mats. When cutting the product to the specified length and width during molding, cutting chips are generated as waste. In addition, waste materials consisting primarily of rock wool are generated at construction sites where rock wool is used, as well as during the demolition of buildings and structures that use rock wool. These waste materials are also disposed of as industrial waste.

[0004] A technology has been disclosed in which waste materials mainly composed of mineral fibers such as rock coul are crushed or directly put into a melting furnace to be melted, and then re-fiberized for reuse (see, for example, Patent Documents 1 and 2). 。 [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 08-061643 [Patent Document 2] Special Publication No. 2008-508174 Summary of the Invention [Problem to be solved by the invention]

[0006] When using rock wool waste that has not been sufficiently fiberized during production or dust collected by a dust collector, even if the waste is crushed or directly put into a melting furnace to be melted and re-fiberized for reuse, there is a risk that the dust will be discharged from the furnace along with the exhaust gas. In addition, there is a risk that the dust will clog the gaps in the raw materials or raw fuel through which combustion gas, combustion air, or oxygen pass, preventing continuous fiberization. 。

[0007] The present invention aims to provide a recycling technology (recycling block and recycling method) for waste rock wool that can be fed into a melting furnace as a raw material for rock wool production, even if the waste rock wool is insufficiently fiberized during rock wool production or is composed of dust collected by a dust collector. The present invention also aims to provide a recycling block for waste rock wool that has a low moisture content and high compressive strength. That is, the present invention aims to provide a recycling block for waste rock wool that has a low moisture content of 0.5% or less and a compressive strength of 1.0 N / mm 2 The present invention aims to provide a block for recycling waste rock wool as described above. Another object of the present invention is to provide a method for recycling waste rock wool that can continuously regenerate a large amount of waste rock wool into rock wool. [Means for solving the problem]

[0008] As a result of intensive research into solving the above problems, the inventors have found that the above problems can be solved by forming a block containing rock wool waste material with a specific light bulk density and specific proportions of cement and water, and have completed the present invention. in Recycled rock wool waste blocks and (2)This is a method of recycling waste rock wool, represented by the formula: (1) Lightly packed bulk density 0.4 g / cm 3 For 100 parts by mass of solids contained in rock wool waste material that is above Rock wool waste material that is 5 to 30 parts by mass of cement and 19 to 35 parts by mass of solids contained in 100 parts by mass A regeneration block is a block that is used to regenerate rock wool waste, characterized by containing parts by mass of water, and is a block that is used to regenerate rock wool waste, characterized by containing parts by mass of water, and is a block that is used to regenerate rock wool waste, characterized by containing parts by mass of water, and is a block that is used to regenerate rock wool waste, characterized by containing parts by mass of water, and is a block that is used to regenerate rock wool waste, characterized by containing parts by mass of water, and ρ=(M1-M0)÷V (1) (2) (1) above Blocks for recycling rock wool waste A method for recycling rock wool waste, characterized in that the waste is put into a melting furnace and melted, and the melted material is fiberized. . [Effects of the Invention]

[0009] According to the present invention, a regeneration technology (regeneration block and regeneration method) for waste rock wool can be obtained, which can be input into a melting furnace as a raw material for rock wool production, even if the waste rock wool is made from insufficient fiberization during rock wool production or from dust collected by a dust collector. Also, according to the present invention, a regeneration block for waste rock wool with a low moisture content and high compressive strength, i.e., a water content of 0.5% or less and a compressive strength of 1.0 N / mm 2 The above-described block for regenerating waste rock wool can be obtained. Furthermore, according to the present invention, a method for regenerating waste rock wool can be obtained, which can continuously regenerate a large amount of waste rock wool into rock wool. DETAILED DESCRIPTION OF THE INVENTION

[0010] The regenerated block of waste rock wool of the present invention has a bulk density of 0.25 g / cm 3or more, 10 to 30 parts by mass of cement per 100 parts by mass of the solid content contained, and 15 to 60 parts by mass of water per 100 parts by mass of the solid content contained, or 3 The recycled block is characterized by containing 5 to 30 parts by mass of cement per 100 parts by mass of solid content, and 15 to 60 parts by mass of water per 100 parts by mass of solid content. This allows the water content of the recycled block to be 0.5% by mass or less and the compressive strength to be 1.0 N / mm 2 The compressive strength is 1.0N / mm 2 If the moisture content of the reclaimed block is 0.5% by mass or less, the reclaimed block is less likely to crumble when it is placed in the melting furnace. Also, if the moisture content of the reclaimed block is 0.5% by mass or less, less heat is lost when the contained moisture evaporates.

[0011] The cement used in the present invention may be any hydraulic cement, such as various portland cements of normal, early strength, extra early strength, low heat and medium heat, white cement, ecocement, and various mixed cements obtained by mixing fly ash, blast furnace slag, silica fume, limestone fine powder or the like with these portland cements, white cement or ecocement, and two or more of these may be used in combination.

[0012] The cement content in the present invention is expressed in parts by mass per 100 parts by mass of the solids contained in the reclamation block of the present invention. In the present invention, if the cement content exceeds 30 parts by mass per 100 parts by mass of the solids contained in the reclamation block, the CaO content in the chemical composition of the reclamation block will be high and the SiO2 content will be low, so it is not possible to add a large amount to the melting furnace. In other words, if a reclamation block with a cement content exceeding 30 parts by mass per 100 parts by mass of the solids contained in the reclamation block is increased in proportion to the raw materials used in normal rock wool production (raw materials whose main chemical composition is CaO, Al2O3, and SiO2), the chemical composition of the raw materials will change beyond the allowable range, so the proportion of the raw materials used in normal rock wool production cannot be increased.

[0013] The amount of water in the present invention is 15 to 60 parts by mass per 100 parts by mass of the solid content contained in the regeneration block of the present invention. If the amount exceeds 60 parts by mass, the water content will be high and the compressive strength will be insufficient. If the amount is less than 15 parts by mass, the compressive strength will also be insufficient. In terms of water content and compressive strength, the amount of water in the present invention is preferably 19 to 50 parts by mass, more preferably 19 to 35 parts by mass, per 100 parts by mass of the solid content contained in the regeneration block of the present invention.

[0014] In the present invention, the loose bulk density ρ refers to the bulk density calculated by the following formula (1): Rock wool waste is gently poured into a container of known volume (V), and without applying any vibration such as tapping to the container, the rock wool waste that protrudes above the top of the container is scraped off (dropped off), and the mass (M1) of the container when it is filled with rock wool waste up to the top is measured, and the mass (M0) of the empty container is used to calculate the loose bulk density. ρ=(M1-M0)÷V (1)

[0015] In the present invention, rock wool refers to a material (mineral fiber) that is produced by rapidly cooling a material that is primarily composed of rock or blast furnace slag melted in a melting furnace and then turned into fiber. For example, rock wool includes slag wool produced from a material that is primarily composed of blast furnace slag.

[0016] Examples of rock wool waste materials used in the present invention include rock wool waste materials that are insufficiently fiberized during rock wool production, rock wool waste materials consisting of dust collected by a dust collector during rock wool production, shavings generated during the cutting process to a specified length or width during the formation of rock wool molded products, rock wool waste materials generated at construction sites using rock wool, and rock wool-based waste materials discarded during the demolition of buildings and structures using rock wool. The rock wool waste materials used in the present invention are preferably one or more types selected from rock wool waste materials that are insufficiently fiberized during rock wool production, rock wool waste materials consisting of dust collected by a dust collector during rock wool production, and shavings generated during the cutting process to a specified length or width during the formation of rock wool molded products, because this facilitates component adjustment during regeneration. Furthermore, if the rock wool waste material used in the present invention is not in a powdery, granular, or short-fiber form, it is preferably pulverized or crushed before use. Even if the rock wool waste material used in the present invention is in a powdery, granular, or short-fiber form, it may be pulverized or crushed before use.

[0017] The present invention preferably provides a pulp having a lumped bulk density of 0.25 g / cm 3 or more, 15 to 30 parts by mass of cement per 100 parts by mass of the solid content contained, and 15 to 50 parts by mass of water per 100 parts by mass of the solid content contained, or Lightly packed bulk density is 0.3g / cm 3 The block for recycling waste rock wool is characterized by containing 10 to 30 parts by mass of cement per 100 parts by mass of solids contained therein, and 15 to 35 parts by mass of water per 100 parts by mass of solids contained therein. This results in a block for recycling waste rock wool with a moisture content of 0.5% or less and a compressive strength of 2.0 N / mm 2 The above-mentioned blocks for recycling the rock wool waste are obtained.

[0018] More preferably, the present invention is a liquefied natural gas having a lining density of 0.4 g / cm 3The block for recycling waste rock wool is characterized by containing 5 to 30 parts by mass of cement per 100 parts by mass of solids contained therein, and 19 to 35 parts by mass of water per 100 parts by mass of solids contained therein. This results in a block for recycling waste rock wool with a moisture content of 0.25% or less and a compressive strength of 1.0 N / mm 2 The above-mentioned blocks for recycling the rock wool waste are obtained.

[0019] In addition to cement, waste rock wool, and water, the reclaimed block of the present invention can contain one or more admixtures, provided that the effects of the present invention are not impaired. Examples of such admixtures include cement polymers, thickeners, cement dispersants, expansive additives, waterproofing agents, rust inhibitors, shrinkage-reducing agents, pigments, fibers other than rock wool, water repellents, anti-efflorescence agents, quick-setting additives, quick-hardening additives, setting retarders, foaming agents, antifoaming agents, gypsum, ground granulated blast furnace slag, pozzolanic substances, water repellents, and surface hardeners.

[0020] The method for recycling waste rock wool of the present invention is characterized in that the above-mentioned blocks for recycling waste rock wool are put into a melting furnace, and the melted material is then fiberized. [Example]

[0021] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples in any way.

[0022] [Example 1] <Making blocks for recycling rock wool waste> Using the materials below, waste rock wool, cement, and water were mixed in a mixer in the proportions shown in Table 1, packed into a plastic mortar form with an inner diameter of 50 mm and an inner height of 100 mm, pressed about 20 mm with a 50 mm diameter cylindrical steel rod to form a pressure shape, and left to stand for 6 days in a room at 20°C and a relative humidity of 60% to produce a block for recycling. The waste rock wool was a suitable mixture of rock wool waste 1 to 3, or some was used alone. <Materials used> Cement: Ordinary Portland cement Rockwool waste 1: Cotton-like waste Rock wool waste 2: Waste material that is insufficiently fiberized during rock wool manufacturing Rock wool waste 3: Waste material consisting of dust collected by a dust collector during rock wool manufacturing Water: Tap water

[0023] [Table 1]

[0024] The produced recycled rock wool blocks were subjected to the following quality evaluation tests. The test results are shown in Table 2. The loose bulk density of the rock wool waste used was also measured and is shown in Table 2. <Compression strength test> The compressive strength of the specimens was determined at a loading rate of 1 mm / min using a precision universal testing machine "Autograph" (product name) manufactured by Shimadzu Corporation. However, the specimens were not capped and were cured for 6 days in a constant temperature room at 20°C and 60% relative humidity. <Moisture content test> The prepared specimens were dried in a dryer with an internal temperature of 105°C until they reached a constant weight, and the moisture content was calculated using the following formula (2) from the mass of the specimen before drying (W0) and the mass of the specimen after drying (after bone dryness) (W1). Moisture content (%)=(W0-W1)÷W1×100 (2)

[0025] [Table 2]

[0026] The recycled blocks of waste rock wool of Level 2-12, which are examples of the present invention, all have a moisture content of 0.5% or less and a compressive strength of 1.0 N / mm 2 That was all. [Industrial Applicability]

[0027] The present invention can be suitably used, for example, in the regeneration of rock wool.

Claims

1. Lightly packed bulk density is 0.4 g / cm 3 The method is characterized in that the waste rock wool is at least 5 to 30 parts by mass of cement per 100 parts by mass of solid content, and 19 to 35 parts by mass of water per 100 parts by mass of solid content. The loose bulk density is determined by gently putting the waste rock wool into a container whose volume (V) is known, scraping off (dropping off) the part of the waste rock wool that protrudes above the top end of the container without applying vibration such as tapping to the container, and measuring the mass (M １ ) and measure the mass of the empty container (M ０ ) A regeneration block is a block that is put into a melting furnace as a raw material when producing rock wool to regenerate rock wool waste material having a light bulk density ρ calculated by the following formula (1). p=(M) １ -M ０ )÷V ・・・・・(1)

2. A method for recycling rock wool waste, characterized in that the rock wool waste recycling block described in claim 1 is placed in a melting furnace and the melted material is fiberized.

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