KR20000072111A - Composition for lightweight aggregate and method for manufacturing the same - Google Patents

Abstract

PURPOSE: A light aggregate composition and preparation thereof is provided which has excellent mechanical strength and low absorption rate, and economical effect due to recycling waste. CONSTITUTION: The preparation method of light aggregate composition comprises the steps of: adding 5-60pts.wt. of clay to at least two wastes selected from the group consisting of 10-50pts.wt. of coal ash, 5-55pts.wt. of EAF(electric arc furnace) dust, 5-35pts.wt. of iron-making slag, and optionally 3-22pts.wt. of paper making sludge incineration material or 3-22pts.wt. of aluminum dross; filter pressing to form a filter cake containing 20-25% of water; aging for 1-3days; primary forming by cutting the extent and then secondary forming by passing rotating tube; drying at 0.5-3hrs. at 100-500°C; sintering at 950-125 0°C in a rotary kiln moving in a rate of 1-4m/min; cooling to 400-500°C

Description

Composition for lightweight aggregate and method for manufacturing the same

The present invention relates to a composition for light weight aggregates and a method for manufacturing the same, and more particularly to a composition for light weight aggregates having excellent mechanical strength and low absorption rate when applied to light weight aggregates by combining various wastes in consideration of their respective compositions. It's about how.

In general, aggregate refers to a building material such as sand, gravel, crushed sand, crushed gravel or crushed stone, which solidifies together with cement or water to make mortar or concrete. When such aggregates are divided according to the place of origin, they can be classified into natural aggregates and artificial aggregates. In addition, when the aggregate is classified by the size of the particles, it is divided into fine aggregate, which is 85% or more of the aggregate passed through the standard mesh of 5mm, which is prescribed in KSA 5101 by weight ratio, and coarse aggregate, which is 85% or more of the standard mesh remaining by the weight ratio. do.

The natural aggregates include river sand and river gravel taken from the bottom of the river, mountain sand and mountain gravel taken from the base or hillside of the mountain area, land sand and land gravel taken from the old river site which is a flat part of the land, and near the coast. Sea pebbles, and the like. The steel sand or steel gravel has a generally round shape and has the most excellent properties for concrete because there is almost no impurity on the aggregate surface, but other aggregates contain a large amount of impurity, so it is required to be sufficiently washed with water. In particular, since sea sand contains salt, there is a high risk of corroding steel reinforcing concrete. Therefore, washing with water or mixing with sand containing salt is not recommended.

The artificial aggregate includes crushed aggregate, artificial lightweight aggregate and blast furnace slag crushed stone. Crushed aggregates include crushed sand or crushed gravel made by crushing rock or jade, and artificial lightweight aggregates are produced by firing expandable shale, expanded clay or fly ash, and blast furnace slag crushed stone is produced as a by-product from steel mills. It is manufactured from blast furnace slag as a raw material.

Generally, when the aggregate is classified by weight, it is usually classified into aggregate, light aggregate, and heavy aggregate. Normal aggregate is about 2.4 ~ 2.6 of the regeneration specific gravity, light weight aggregate refers to the aggregate having a specific gravity of less than about 2.5, the weight aggregate refers to having a specific gravity of about 2.7 or more.

Such lightweight aggregates are classified into three types: artificial lightweight aggregates, natural lightweight aggregates, and Busan lightweight aggregates. Currently, Busan lightweight aggregates are under development in Korea.

Concrete made of the natural lightweight aggregate is not only weak in strength and bad shape, but also its use is gradually reduced for efficient use of resources and preservation and maintenance of the natural environment due to exhaustion of natural resources. Therefore, in the future, a lot of concrete using artificial light aggregate aggregated by crushing or pulverizing shale, blast furnace slag, clay, diatomaceous earth, or fly sah and then assembled is expected to be used.

The requirements for aggregates used in construction and civil concrete are light and of a certain strength, the shape of which is close to spherical or polyhedral, the particle size being appropriate, clean and harmful amounts of organic impurities, chlorides or clay masses It should not contain impurities such as it, it should be durable and fireproof, it should be physically and chemically stable, it should have a certain weight, it should have a surface texture with high adhesion to cement paste, and In order to control the quality of concrete, aggregate quality needs to be stable and the necessary requirements must be secured.

In recent years, natural aggregates are environmentally friendly at low cost by utilizing industrial wastes such as fly ash, paper sludge, waste incinerator, wastewater sludge, etc. Research is underway to manufacture building materials.

As a result of such a study, a method for manufacturing artificial lightweight aggregate by sintering paper sludge, paper sludge incineration ash, coal mine waste rock, waste glass, sewage sludge or coal ash mainly with clay and then sintering is disclosed in Korean Patent Publication No. 96-11333 (Invention) Name: artificial light weight aggregate and its manufacturing method), Republic of Korea Patent No. 10-208779 (Invention: Light weight aggregate and a method of manufacturing a film formed on the skin) or Republic of Korea Patent No. 10-240943 (Name of the invention: red mud Method for producing porous lightweight building materials).

FIG. 1 is a block diagram illustrating a process of manufacturing an artificial lightweight aggregate disclosed in Patent Publication No. 96-11333.

As shown in the patent, as shown in FIG. 1, paper sludge or paper sludge incineration material is wet mixed with clay, and then molded into a predetermined shape to form a molded body. At this time, the paper sludge and / or paper sludge incineration ash is added at a ratio of about 10 to 70% by weight based on the total mixture.

Subsequently, the molded product is put into a dry oven, preliminarily dried at a temperature of about 100 ° C., and then sintered at a high temperature of about 1200 to 1250 ° C. to produce an artificial lightweight aggregate.

In general, a porous lightweight body prepared using a clay and other siliceous materials is called expanded clay. Currently, expanded clay in the form of pellets is commercially available under the trade names LECA, HAYDIT and KERAMSIT.

One of the conditions for the process of swelling clay to work properly is that the starting material clay must have a well defined narrow composition range. In other words, many experiments are required to obtain a suitable composition range of silica (SiO ₂ ): alumina (Al ₂ O ₃ ) for fluxing agents and organic substances. ) And the like are used.

As such, various temperature curves have been proposed to obtain suitable sintering conditions for clays used as lightweight aggregates.

Among them, it is preferable to maintain the atmosphere in the kiln in a reducing atmosphere in the low sintering temperature section, and to maintain the atmosphere in the kiln in the oxidizing atmosphere in the sintering temperature section after the gas is formed. To this end, a method of transferring the sintered body from one kiln to another kiln during firing, or from one part of one kiln to another, may be applied.

In general, the raw material of the lightweight aggregate starts melting of some components of the molded body upon heating, and the surface of the molded body is surrounded by the liquid phase. At the same time, gas is generated from some components and the pressure of the gas increases with increasing temperature, but the viscosity of the liquid phase decreases, causing foaming. In this case, when the gas pressure in the lightweight aggregate increases, the decomposition temperature rises, and the gas is dissolved in the solution, thereby delaying the generation of the gas to a high temperature.

In the case of expanded clay, the gases produced are mainly oxygen and carbon dioxide, and sulfur dioxide gas is produced when sulfur is present. If the raw material which has undergone much weathering is used or the firing temperature is delayed and the carbon component or sulfur component is lost, the foaming capacity of the lightweight aggregate is reduced. However, there is a possibility that water vapor generated by the decomposition of the crystal water contained in the clay mineral may help foaming of the lightweight aggregate.

As described above, there are various patents related to a method for manufacturing lightweight aggregate using various wastes, but many of them have not been put to practical use at present.

The reason why the artificial lightweight aggregate manufactured by using waste is not practical can be largely as follows. First, the biggest reason is that the production cost for manufacturing lightweight aggregate is too high to satisfy the economic feasibility. Next, the manufactured lightweight aggregate does not have excellent characteristics as lightweight aggregate such as mechanical strength and water absorption. to be.

The present invention has been made to solve the above problems, one object of the present invention is to properly combine the appropriate waste as a source of liquid and gas required for foaming to enable the production of a variety of waste as a lightweight aggregate in consideration of their respective composition It is thereby to provide a lightweight aggregate composition having excellent mechanical strength and low water absorption and at the same time economical.

Another object of the present invention is to provide a method for producing a composition for lightweight aggregate, which is particularly suitable for producing the composition for lightweight aggregate.

1 is a block diagram illustrating a conventional method for manufacturing artificial lightweight aggregate.

Figure 2 is a block diagram for explaining a method for producing a composition for lightweight aggregate according to the present invention.

In order to achieve the above object of the present invention, according to an embodiment of the present invention, two selected from the waste group consisting of 10 to 50 parts by weight of coal ash, 5 to 55 parts by weight of EAF dust and 5 to 35 parts by weight of steel slag The composition for light weight aggregates which adds 5-60 weight part of clays to the above waste is provided.

Preferably, the light weight aggregate composition may further include 3 to 22 parts by weight of paper sludge incineration ash or 3 to 22 parts by weight of aluminum dross.

In addition, in order to achieve the above object of the present invention, according to another embodiment of the present invention, 3 to 42 parts by weight of EAF dust, 5 to 35 parts by weight of coal ash, 15 to 55 parts by weight of stone powder and 5 to 5 parts of sewage sludge incinerators. There is provided a composition for light weight aggregates comprising 3 to 62 parts by weight of clay to at least two wastes selected from a waste group consisting of 45 parts by weight. In this case, the light aggregate composition may further include 3 to 17 parts by weight of aluminum dross or 5 to 35 parts by weight of red mud.

In order to achieve the above object of the present invention, according to the present invention, at least two or more wastes selected from the waste group consisting of coal ash, EAF dust, steel slag, sewage sludge ash, stone flour, paper sludge incineration ash and aluminum dross, respectively. Combining according to a chemical composition, adding clay to the waste to form a mixture, filtering the mixture to form a filter cake, aging the filter cake, and first molding the filter cake. Forming a first molded body, primary molding the first molded body to form a second molded body, drying the second molded body, sintering the dried second molded body to form a sintered body, and Cooling the sintered body of the lightweight aggregate composition comprising the step of forming a composition for lightweight aggregate A manufacturing method is provided.

The step of forming the mixture is carried out by wet mixing for 1 to 5 hours using a ball mill, tube mill or stirrer, and the filter cake has a water content of 20 to 25 percent (%). In addition, the step of aging the filter cake is performed for 1 to 3 days.

The forming of the first molded body may further include cutting the first molded body into a predetermined size, and the forming of the second molded body may be performed while passing through the barrel rotating the first molded body at a predetermined speed. Is performed.

The drying of the second molded body is carried out in an oven and is carried out for 0.5 to 3 hours at a temperature of 100 ~ 500 ℃, the step of forming the sintered body is put the second molded body in a rotary kiln The second molded body is carried out at a speed of 1 to 4 meters / minute at a temperature of 950 to 1250 ° C. In this case, the second molded body is introduced at about 5 to 20% based on the cross-sectional area of the rotary kiln.

The sintered compact is gradually cooled to a temperature of 400 to 500 ° C. while passing through a cooler.

In a preferred embodiment of the present invention, in order to form a composition for light weight aggregate, steel waste and aluminum hydroxide, such as EAF (Electric Arc Furnace) dust to steelmaking slag, in order to form a liquid phase from the molded body in the firing temperature range Red mud from the production process is used. These are wastes having a high Fe ₂ O ₃ content and are reduced to FeO at the firing temperature to generate oxygen (O ₂ ) gas and thus become a source of gas generation.

In addition, in the manufacture of a lightweight aggregate composition according to another preferred embodiment of the present invention, incineration ash containing a small amount of unburned carbon components, such as coal ash, paper sludge incineration to sewage sludge incineration, or the like, or oxidizing properties compared to iron By adding aluminum dross containing a large aluminum (Al) metal, it is possible to facilitate the reduction of iron oxide and promote the generation of oxygen (O ₂ ) gas.

In the case of using the artificial combination of the components required for the production of lightweight aggregate, the price of the raw material is expensive, but there is a problem that it is very difficult to uniformly mix the components. On the other hand, in the case of producing lightweight aggregate by combining appropriate wastes as in the present invention, the desired components are already uniformly mixed and the raw material costs are almost insignificant.

According to the present invention, a composition for light aggregate having excellent mechanical strength and low water absorption can be prepared by appropriately mixing and sintering various wastes according to their respective compositions. In addition, according to the present invention, since the lightweight aggregate is produced through a combination of suitable waste, the raw material cost is almost inexpensive, so it has economic advantages. Moreover, it is possible to recycle various waste materials, which are causing serious environmental problems in recent years, which has a significant advantage in terms of national economy.

Hereinafter, a light aggregate composition and a method of manufacturing the same according to preferred embodiments of the present invention will be described in detail.

Figure 2 shows a block diagram for explaining the process of manufacturing a composition for lightweight aggregate according to the present invention.

Referring to FIG. 2, first, a waste including clay and the following components, alone or in combination of various kinds, is used to make a suitable combination for preparing a composition for lightweight aggregate.

Table 1 and Table 2 show the results of analyzing the chemical composition of various wastes and clays according to the present invention.

As shown in Table 1 and Table 2, according to the present invention, various wastes are classified as follows according to their chemical composition.

First, it is a waste consisting of components capable of forming glass by eutectic reaction with silica components including alkali and alkaline earth components to various metal oxides, and foaming reaction by containing organic materials and Fe ₂ O _3, etc. Such wastes may include EAF dust, steel slag, stone powder, red mud, waste foundry sand or sewage sludge incineration.

In addition, there are wastes such as ash ash, such as coal ash and paper sludge incineration ash, which contain unburned carbon components capable of causing a reduction reaction of Fe ₂ O ₃ , and wastes such as aluminum dross containing aluminum. These wastes are properly combined as described above according to their respective roles.

The sewage sludge incineration material contains a small amount of unburned carbon components and contains a small amount of unburned carbon components and a component capable of forming a liquid phase at the time of firing, such as many alkali and alkaline earth components and phosphorus components, and foaming. It will include all of the various components necessary for the preparation of the composition. However, since it is difficult to satisfy the required amount of glass and the degree of foaming only by the sewage sludge incinerator itself, it is preferable to add necessary components according to the composition of the sewage sludge incinerator.

In the case of the EAF dust, since the glass-forming component and the iron component are contained in a large amount, it is preferable to add aluminum dross or coal ash to the EAF dust in order to enhance the reduction of the iron component.

The combined waste and clay are then mixed by wet mixing to form a mixture. At this time, in order to produce a composition for light weight aggregate having a uniform pore structure, various wastes and clay are uniformly mixed using a ball mill, a tube mill, a stirrer, or the like.

In order for the light aggregate composition according to the present invention to have a uniform internal pore structure, the decomposition reaction of the organic material and the decomposition reaction of Fe ₂ O ₃ must occur uniformly, and therefore, it is necessary to mix the respective components uniformly. In particular, the mixing process is more important when relatively small amounts are added, such as aluminum dross.

In the wet mixing process, waste combined with a desired composition is added to an appropriate amount of water, and then sufficiently mixed using a ball mill, a tube mill, or an agitator. In the case of using the ball mill, it is sufficient to perform the wet mixing process for about 1 to 5 hours because the mixing is more preferable than the grinding effect. If a stirrer is used, a longer time is required for a ball mill for uniform mixing of each waste and clay.

Next, the mixture is subjected to a filter press step to remove water inside the mixture to form a filter cake. This filter pressing process results in a filter cake having a water content of about 20 to 25 percent (%).

Subsequently, the filter cake is aged for about 1 to 3 days through an aging process to uniformly control the water distribution in the filter cake.

Subsequently, the aged filter cake is first molded using a vacuum grinder to form a first molded body, and then the first molded body is cut into a predetermined size.

Next, the first molded body is secondarily molded into a second molded body having a spherical shape by using a granulator. In other words, the first molded body is made to pass through a cylinder rotating at a constant speed to form a spherical shape. In this case, the shape of the second molded body does not necessarily have to be spherical, and having a shape without angled portions is sufficient to be applied as a lightweight aggregate.

Subsequently, the second molded body is put into an oven, and then dried at a temperature of about 100 to 500 ° C. for about 0.5 to 3 hours to form a dried body. At this time, the drying time of the second molded body is determined by the drying temperature and the size of the second molded body, and in the case of a small molded body, the drying time is shortened. Preferably, the microwave can be irradiated to the second molded article to shorten the time for drying the molded article. In addition, the second molded body may be dried using waste heat generated from a rotary kiln used in the firing process described later.

Next, the dried body is put into a rotary kiln and fired to form a sintered body. At this time, the maximum temperature inside the rotary kiln is about 1050 ~ 1200 ℃, the drying body moves at a speed of about 1 to 4 meters / minute from the inlet of the rotary kiln to the maximum temperature range inside the rotary kiln. Preferably, the amount of the dry matter added to the rotary kiln is adjusted to be about 5 to 20% based on the cross-sectional area of the rotary kiln.

Finally, the sintered body after baking is cooled using a cooler to complete the composition for lightweight aggregate. In this case, the sintered compact is gradually cooled to a temperature of about 400 to 500 ° C. while passing through the cooler.

Properties such as absorption, specific gravity, and strength measured for the light weight aggregate composition prepared as described above are as follows.

First, lightweight aggregate compositions containing coal ash, EAF dust and clay as main components have a relatively wide range of absorption rate from 0.91 to 10.01 percent, specific gravity of 1.04 to 2.34, and strength of 2,558 to 25,095 psi.

Next, compositions based on steel slag, coal ash and clay have an absorption rate on the order of 1.73 to 7.00%, a specific gravity of 1.20 to 2.96 and a strength in the range of 3,084 to 29,800 psi.

In addition, compositions comprising coal ash, EAF dust, steel slag and clay as the main components have an absorption of about 1.73 to 10.00%, a specific gravity of 1.25 to 2.82 and a strength in the range of 6,039 to 22,563 psi.

Compositions comprising EAF dust, stone dust and clay as the main component have an absorption of about 1.40 to 6.56%, a specific gravity of 0.81 to 1.92 and a strength in the range of 4,860 to 8,697 psi.

In addition, compositions containing EAF dust, sewage sludge incinerator, stone powder and clay as main components have an absorption rate of about 4.10 to 7.38%, specific gravity of 0.98 to 1.79, and strengths in the range of 4,974 to 10,174 psi. And clays were found to have an absorption of about 2.34 to 7.97%, specific gravity of 0.81 to 1.92 and strength in the range of 4,931 to 10,302 psi.

Therefore, the composition for lightweight aggregate according to the present invention satisfies all criteria as aggregates, and in particular, the mechanical strength and water absorption are evaluated to be very superior to the conventional artificial lightweight aggregates.

Hereinafter, a light aggregate composition and a method of manufacturing the same according to the preferred experimental examples of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited or limited by the following experimental examples.

Experimental Example 1

According to the chemical composition of Table 1 and Table 2, 40 parts by weight of coal ash, which is a waste, and 10 parts by weight of EAF dust were combined, and then 50 parts by weight of clay was added and wet mixed to prepare a mixture. In this case, a clay was added to the coal ash and the EAF dust, and then wet mixed for about 3 hours using a ball mill to prepare a mixture of the waste and the clay uniformly. This wet mixing process is a process of uniformly mixing various wastes such as coal ash, EAF dust, and the like with clay, and is an essential process for producing a composition for lightweight aggregate having a uniform pore structure later.

The mixture was then filter pressed to form a filter cake. The filter cake passed through the filter pressing has a water content of about 22%.

Next, by aging the filter cake for about two days to uniformize the distribution of moisture in the filter cake, and then using a vacuum grinder to filter the filter cake, for example, a predetermined shape such as a rod shape. Primary molding was performed to form a first molded body.

Subsequently, the first molded body was cut to an appropriate size, and then second molded using a granulator to form a second molded body having a spherical shape.

Subsequently, the second molded body was put in an oven and dried at a temperature of about 300 ° C. for about 1 hour and 30 minutes, and then, the dried second molded body was put in a rotary kiln to produce a second molded body at a temperature of about 1150 ° C. Sintering was carried out while moving at a speed of about 2 meters / minute to form a sintered body. At this time, the second molded body is sintered while moving from the inlet of the rotary kiln to the outlet for about 60 minutes.

Finally, the composition for lightweight aggregate was completed by gradually cooling the sintered body to a temperature of about 450 ° C. using a cooler.

As a result of measuring the properties of the composition for lightweight aggregate according to the present experimental example, the water absorption is 1.86 percent, specific gravity is 1.74, and the strength is 7,827 psi.

Experimental Example 2

40 parts by weight of coal ash and 20 parts by weight of EAF dust were combined, and then 40 parts by weight of clay was added and wet mixed to prepare a mixture.

In this Experimental Example, except that the firing process is performed at about 1050 ℃, the manufacturing process of the composition for lightweight aggregate according to this Experimental Example is the same as the Experimental Example 1 described above.

The light aggregate composition according to this Experimental Example has an absorption rate of 7.95 percent, a specific gravity of 1.82 and a strength of 8,821 psi.

Experimental Example 3

After mixing 40 parts by weight of coal ash, 25 parts by weight of EAF dust, 10 parts by weight of aluminum dross and 5 parts by weight of papermaking sludge incinerator, 20 parts by weight of clay was added and wet mixed to prepare a mixture.

In this Experimental Example, except that the firing process is carried out at about 1100 ℃ and the moving speed of the molded body is about 3 meters / min, the manufacturing process of the lightweight aggregate composition according to the present Experimental Example 1 and same.

The lightweight aggregate composition according to this experimental example had an absorption rate of 3.43 percent, a specific gravity of 1.34, and a strength of 4,527 psi.

Experimental Example 4

After combining 40 parts by weight of coal ash and 30 parts by weight of EAF dust, 30 parts by weight of clay was added and wet mixed to prepare a mixture.

In this Experimental Example, except that the firing process is performed at about 1050 ℃, the manufacturing process of the composition for lightweight aggregate according to this Experimental Example is the same as the Experimental Example 1 described above.

As a result of measuring the properties of the composition for light weight aggregates according to this experimental example, the water absorption was 4.00 percent, the specific gravity was 2.07, and the strength was 14,524 psi.

Experimental Example 5

A mixture was prepared by combining 40 parts by weight of EAF dust and 30 parts by weight of ash, adding 30 parts by weight of clay, and then wet mixing.

In this Experimental Example, except that the firing process is carried out at about 1100 ℃ the manufacturing process of the composition for lightweight aggregate according to this Experimental Example is the same as the Experimental Example 1 described above.

The light aggregate composition according to this experimental example was measured to have an absorption rate of 1.51 percent, a specific gravity of 2.02, and a strength of 23,238 psi.

Experimental Example 6

50 parts by weight of EAF dust and 30 parts by weight of coal ash were combined, 20 parts by weight of clay was added, followed by wet mixing to prepare a mixture.

In this Experimental Example, except that the firing process is performed at about 1150 ℃, the manufacturing process of the light weight aggregate composition according to this Experimental Example is the same as the Experimental Example 1 described above.

The light aggregate composition according to this experimental example was measured to have an absorption rate of 2.53 percent, a specific gravity of 2.11, and a strength of 16,038 psi.

Experimental Example 7

A mixture was prepared by combining 50 parts by weight of EAF dust, 30 parts by weight of ash, and 20 parts by weight of paper sludge incinerator, followed by wet mixing in the absence of clay.

In the present experimental example, the mixing process was performed for about 6 hours using a stirrer, and the firing process was performed while moving the dry body at a rate of about 3 meters / minute at a temperature of about 1100 ° C.

The light aggregate composition according to this experimental example was measured to have a water absorption of 4.31 percent, a specific gravity of 2.20 and a strength of 20,212 psi.

Experimental Example 8

50 parts by weight of EAF dust, 30 parts by weight of ash, and 10 parts by weight of paper sludge incineration ash were combined, followed by addition of 20 parts by weight of clay.

In this Experimental Example, the firing process is performed at about 1050 ° C.

The light aggregate composition according to the present experimental example was measured to have a water absorption of 0.91 percent, a specific gravity of 2.34 and a strength of 25,095 psi.

Experimental Example 9

30 parts by weight of coal ash, 10 parts by weight of EAF dust and 10 parts by weight of aluminum dross were combined and 50 parts by weight of clay was added.

In this Experimental Example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 7.95 percent, a specific gravity of 2.15 and a strength of 14,2105 psi.

Experimental Example 10

50 parts by weight of clay was added to 30 parts by weight of ash, 15 parts by weight of EAF dust and 5 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 1.51 percent, a specific gravity of 1.58, and a strength of 5,215 psi.

Experimental Example 11

45 parts by weight of clay was added to 30 parts by weight of ash, 15 parts by weight of EAF dust and 10 parts by weight of aluminum dross.

In this experimental example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this experimental example was measured to have an absorption rate of 2.53 percent, a specific gravity of 1.52, and a strength of 7,347 psi.

Experimental Example 12

40 parts by weight of clay was added to 30 parts by weight of ash, 15 parts by weight of EAF dust and 15 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have a water absorption of 4.31 percent, a specific gravity of 1.94 and a strength of 7,574 psi.

Experimental Example 13

45 parts by weight of clay was added to 30 parts by weight of ash, 20 parts by weight of EAF dust and 5 parts by weight of aluminum dross.

In this experimental example, the firing process was carried out at about 1150 ℃, the light aggregate composition according to this experimental example was measured to have a water absorption of 0.91 percent, specific gravity of 1.17 and strength of 4,263 psi.

Experimental Example 14

40 parts by weight of clay was added to 30 parts by weight of ash, 20 parts by weight of EAF dust and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was carried out at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.43 percent, a specific gravity of 1.16 and a strength of 4,021 psi.

Experimental Example 15

35 parts by weight of clay was added to 30 parts by weight of ash, 20 parts by weight of EAF dust and 15 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.76 percent, a specific gravity of 1.26 and a strength of 3,533 psi.

Experimental Example 16

30 parts by weight of clay was added to 30 parts by weight of ash, 20 parts by weight of EAF dust and 20 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have a water absorption of 10.01 percent, a specific gravity of 1.46, and a strength of 4,547 psi.

Experimental Example 17

35 parts by weight of clay was added to 30 parts by weight of ash, 30 parts by weight of EAF dust and 5 parts by weight of aluminum dross.

In this experimental example, the firing process is carried out at about 1150 ℃, the light aggregate composition according to this experimental example has a water absorption of 2.32 percent, specific gravity of 1.31 and strength of 2,842 psi.

Experimental Example 18

30 parts by weight of clay was added to 30 parts by weight of ash, 30 parts by weight of EAF dust and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have a water absorption of 2.16 percent, a specific gravity of 1.04 and a strength of 2,558 psi.

Experimental Example 19

20 parts by weight of clay was added to 40 parts by weight of EAF dust, 30 parts by weight of ash, and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 7.05 percent, a specific gravity of 1.26, and a strength of 2,842 psi.

Experimental Example 20

40 parts by weight of clay was added to 40 parts by weight of coal ash and 20 parts by weight of steel slag.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example had an absorption rate of 7.00 percent, a specific gravity of 2.86, and a strength of 23,701 psi.

Experimental Example 21

30 parts by weight of clay was added to 30 parts by weight of paper sludge incineration ash, 20 parts by weight of coal ash and 20 parts by weight of steel slag.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 7.00 percent, a specific gravity of 2.32, and a strength of 21,172 psi.

Experimental Example 22

40 parts by weight of clay was added to 30 parts by weight of ash and 30 parts by weight of steel slag.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have a water absorption of 4.02 percent, a specific gravity of 2.88 and a strength of 25,524 psi.

Experimental Example 23

Twenty parts by weight of clay was added to 30 parts by weight of steel slag, 30 parts by weight of paper sludge incineration ash, and 20 parts by weight of coal ash.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.02 percent, a specific gravity of 2.40, and a strength of 20,374 psi.

Experimental Example 24

30 parts by weight of clay was added to 40 parts by weight of the steel slag and 30 parts by weight of the ash ash.

In this experimental example, the firing process is carried out at about 1150 ℃, the light aggregate composition according to this experimental example has a water absorption of 1.73 percent, specific gravity of 2.96 and strength of 28,800 psi.

Experimental Example 25

40 parts by weight of steel slag, 20 parts by weight of coal ash and 20 parts by weight of clay were added to 20 parts by weight of paper sludge incineration ash.

In this experimental example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this experimental example was measured to have an absorption rate of 1.73 percent, a specific gravity of 2.44, and a strength of 22,674 psi.

Experimental Example 26

20 parts by weight of clay was added to 50 parts by weight of the steel slag and 30 parts by weight of the ash ash.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have a water absorption of 2.00 percent, a specific gravity of 3.04 and a strength of 29,800 psi.

Experimental Example 27

10 parts by weight of clay was added to 50 parts by weight of steel slag, 20 parts by weight of coal ash, and 20 parts by weight of paper sludge incineration ash.

In this Experimental Example, the firing process was performed at about 1000 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 2.00 percent, a specific gravity of 2.52, and a strength of 23,956 psi.

Experimental Example 28

55 parts by weight of clay was added to 30 parts by weight of ash, 10 parts by weight of steel slag, and 5 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 1.86 percent, a specific gravity of 1.83, and a strength of 9,237 psi.

Experimental Example 29

40 parts by weight of clay was added to 30 parts by weight of ash, 10 parts by weight of steel slag, and 20 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1000 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.00 percent, a specific gravity of 2.06, and a strength of 9,038 psi.

Experimental Example 30

30 parts by weight of clay was added to 30 parts by weight of ash, 30 parts by weight of steel slag, and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.02 percent, a specific gravity of 1.26 and a strength of 3,084 psi.

Experimental Example 31

10 parts by weight of clay was added to 50 parts by weight of the steel slag, 20 parts by weight of coal ash and 20 parts by weight of EAF dust.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.76 percent, a specific gravity of 2.82 and a strength of 22,025 psi.

Experimental Example 32

A mixture was prepared by adding 20 parts by weight of clay to 40 parts by weight of steel slag, 20 parts by weight of coal ash and 20 parts by weight of EAF dust.

In this Experimental Example, the firing process was performed at about 1000 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 10.00 percent, a specific gravity of 2.77, and a strength of 20,351 psi.

Experimental Example 33

Twenty parts by weight of clay was added to 30 parts by weight of the steel slag, 30 parts by weight of EAF dust, and 20 parts by weight of coal ash.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.30 percent, a specific gravity of 2.73, and a strength of 21,208 psi.

Experimental Example 34

30 parts by weight of clay was mixed with 30 parts by weight of EAF dust, 20 parts by weight of steel slag, and 20 parts by weight of coal ash.

In this Experimental Example, the firing process was performed at about 1000 ° C., and the light aggregate composition according to this Experimental Example was measured to have a water absorption of 2.00 percent, a specific gravity of 2.68, and a strength of 22,563 psi.

Experimental Example 35

30 parts by weight of clay was mixed with 30 parts by weight of coal ash, 20 parts by weight of aluminum dross, 10 parts by weight of steel slag, and 10 parts by weight of EAF dust.

In this experimental example, the firing process was carried out at about 1150 ℃, the light aggregate composition according to this experimental example was measured to have an absorption of 3.30 percent, a specific gravity of 1.25 and a strength of 6,750 psi.

Experimental Example 36

30 parts by weight of clay was mixed with 30 parts by weight of ash, 15 parts by weight of steel slag, 15 parts by weight of EAF dust and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 1.73 percent, a specific gravity of 1.40, and a strength of 6,039 psi.

Experimental Example 37

65 parts by weight of clay was mixed with 20 parts by weight of stone powder, 10 parts by weight of EAF dust and 5 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.94 percent, a specific gravity of 1.72, and a strength of 7,546 psi.

Experimental Example 38

30 parts by weight of stone powder, 10 parts by weight of EAF dust and 10 parts by weight of aluminum dross were mixed with 50 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption of 4.50 percent, a specific gravity of 1.58, and an intensity of 8,085 psi.

Experimental Example 39

40 parts by weight of stone powder, 10 parts by weight of EAF dust and 5 parts by weight of aluminum dross were mixed with 45 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption of 3.80 percent, a specific gravity of 1.28, and a strength of 6,451 psi.

Experimental Example 40

50 parts by weight of clay was mixed with 20 parts by weight of stone powder, 20 parts by weight of EAF dust and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 6.56 percent, a specific gravity of 0.95, and a strength of 5,400 psi.

Experimental Example 41

45 parts by weight of clay was mixed with 30 parts by weight of stone powder, 20 parts by weight of EAF dust and 5 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.23 percent, a specific gravity of 1.03, and a strength of 5,613 psi.

Experimental Example 42

40 parts by weight of stone powder, 30 parts by weight of EAF dust and 10 parts by weight of aluminum dross were mixed with 20 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.34 percent, a specific gravity of 0.87, and a strength of 5,286 psi.

Experimental Example 43

5 parts by weight of clay was mixed with 50 parts by weight of stone powder, 30 parts by weight of EAF dust and 15 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.92 percent, a specific gravity of 0.81 and a strength of 4,860 psi.

Experimental Example 44

30 parts by weight of clay was wet-mixed to 40 parts by weight of stone powder and 30 parts by weight of EAF dust.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 1.40 percent, a specific gravity of 1.92 and a strength of 4,931 psi.

Experimental Example 45

25 parts by weight of clay was wet mixed with 40 parts by weight of EAF dust, 30 parts by weight of stone powder and 5 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.70 percent, a specific gravity of 0.82, and a strength of 6,634 psi.

Experimental Example 46

20 parts by weight of clay was mixed with 40 parts by weight of EAF dust, 30 parts by weight of stone powder and 10 parts by weight of aluminum dross.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.50 percent, a specific gravity of 1.22 and a strength of 8,697 psi.

Experimental Example 47

20 parts by weight of stone powder, 10 parts by weight of EAF dust and 10 parts by weight of sewage sludge ash were mixed with 60 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 6.83 percent, a specific gravity of 1.79 and a strength of 7,716 psi.

Experimental Example 48

30 parts by weight of stone powder, 10 parts by weight of EAF dust and 10 parts by weight of sewage sludge ash were mixed with 50 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 6.42 percent, a specific gravity of 1.64, and a strength of 8,128 psi.

Experimental Example 49

40 parts by weight of clay, 10 parts by weight of EAF dust, and 10 parts by weight of sewage sludge ash were mixed with 40 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.21 percent, a specific gravity of 1.34 and a strength of 6,465 psi.

Experimental Example 50

40 parts by weight of clay was mixed with 20 parts by weight of stone powder, 20 parts by weight of EAF dust and 20 parts by weight of sewage sludge ash.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 7.38 percent, a specific gravity of 1.02, and a strength of 5,542 psi.

Experimental Example 51

30 parts by weight of clay was mixed with 20 parts by weight of EAF dust and 20 parts by weight of sewage sludge incinerator.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 6.47 percent, a specific gravity of 1.21 and a strength of 5,698 psi.

Experimental Example 52

10 parts by weight of clay was mixed with 40 parts by weight of stone powder, 30 parts by weight of sewage sludge ash, and 20 parts by weight of EAF dust.

In this Experimental Example, the firing process was performed at about 1080 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.11 percent, a specific gravity of 1.08 and a strength of 5,499 psi.

Experimental Example 53

10 parts by weight of clay was wet mixed with 40 parts by weight of sewage sludge ash, 30 parts by weight of stone powder and 20 parts by weight of EAF dust.

In this Experimental Example, the firing process was carried out at about 1050 ° C, and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 6.58 percent, a specific gravity of 0.98 and a strength of 4,974 psi.

Experimental Example 54

30 parts by weight of clay was mixed with 30 parts by weight of EAF dust, 20 parts by weight of stone powder and 20 parts by weight of sewage sludge ash.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.10 percent, a specific gravity of 1.45, and a strength of 5,045 psi.

Experimental Example 55

20 parts by weight of clay was mixed with 30 parts by weight of stone powder, 30 parts by weight of EAF dust, and 20 parts by weight of sewage sludge ash.

In this experimental example, the firing process was performed at about 1000 ° C., and the light aggregate composition according to this experimental example was measured to have an absorption rate of 5.34 percent, a specific gravity of 1.63, and a strength of 10,174 psi.

Experimental Example 56

20 parts by weight of clay was mixed with 30 parts by weight of stone powder, 30 parts by weight of EAF dust, and 20 parts by weight of sewage sludge ash.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.12 percent, a specific gravity of 1.14, and an intensity of 8,881 psi.

Experimental Example 57

60 parts by weight of clay was wet mixed with 20 parts by weight of stone powder, 10 parts by weight of coal ash and 10 parts by weight of red mud.

In this experimental example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this experimental example was measured to have an absorption rate of 7.97 percent, a specific gravity of 1.72, and an intensity of 8,057 psi.

Experimental Example 58

50 parts by weight of clay was wet-mixed to 30 parts by weight of stone powder, 10 parts by weight of coal ash and 10 parts by weight of red mud.

In this experimental example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this experimental example was measured to have an absorption rate of 6.34 percent, a specific gravity of 1.58, and an intensity of 8,327 psi.

Experimental Example 59

40 parts by weight of clay, 10 parts by weight of coal ash and 10 parts by weight of red mud were mixed with 40 parts by weight of clay.

In this experimental example, the firing process was performed at about 1200 ° C., and the light aggregate composition according to this experimental example was measured to have an absorption rate of 5.37 percent, a specific gravity of 1.28, and a strength of 6,849 psi.

Experimental Example 60

40 parts by weight of clay was wet-mixed to 20 parts by weight of stone powder, 20 parts by weight of coal ash and 20 parts by weight of red mud.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.27 percent, a specific gravity of 0.95 and a strength of 5,968 psi.

Experimental Example 61

30 parts by weight of clay, 20 parts by weight of coal ash and 20 parts by weight of red mud were wet mixed with 30 parts by weight of clay.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 5.71 percent, a specific gravity of 1.03, and a strength of 5,982 psi.

Experimental Example 62

10 parts by weight of clay was wet-mixed to 40 parts by weight of stone powder, 30 parts by weight of coal ash and 20 parts by weight of red mud.

In this Experimental Example, the firing process was performed at about 1150 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.26 percent, a specific gravity of 0.87 and a strength of 5,670 psi.

Experimental Example 63

50 parts by weight of stone powder, 20 parts by weight of coal ash and 20 parts by weight of red mud were wet mixed with 10 parts by weight of clay.

In this experimental example, the firing process was carried out at about 1150 ℃, the light aggregate composition according to this experimental example was measured to have a water absorption of 0.81 percent, specific gravity of 0.81 and strength of 5,215 psi.

Experimental Example 64

30 parts by weight of red mud, 20 parts by weight of stone powder and 20 parts by weight of coal ash were wet-mixed.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 3.22 percent, a specific gravity of 1.92 and a strength of 4,931 psi.

Experimental Example 65

20 parts by weight of clay was wet-mixed to 30 parts by weight of stone powder, 30 parts by weight of red mud, and 20 parts by weight of coal ash.

In this Experimental Example, the firing process was performed at about 1050 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 2.34 percent, a specific gravity of 1.53, and a strength of 10,302 psi.

Experimental Example 66

20 parts by weight of clay was wet-mixed to 30 parts by weight of stone powder, 30 parts by weight of red mud, and 20 parts by weight of coal ash.

In this Experimental Example, the firing process was performed at about 1100 ° C., and the light aggregate composition according to this Experimental Example was measured to have an absorption rate of 4.15 percent, a specific gravity of 1.22, and a strength of 7,956 psi.

According to the present invention, it is possible to prepare a composition for lightweight aggregate having excellent mechanical strength and low water absorption by forming, drying and sintering by appropriately mixing various wastes according to their respective compositions.

In addition, according to the present invention, since the lightweight aggregate is manufactured through a suitable waste combination, the raw material cost is almost inexpensive, and thus, the economical advantages are remarkable. It also has a significant advantage in terms of national economy.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be appreciated.

Claims (10)

A light aggregate composition comprising 5 to 60 parts by weight of clay to two or more wastes selected from the group consisting of 10 to 50 parts by weight of coal ash, 5 to 55 parts by weight of EAF dust and 5 to 35 parts by weight of steel slag. The method of claim 1, The composition for light weight aggregates, further comprising 3 to 22 parts by weight of papermaking sludge incineration. The method of claim 1, A lightweight aggregate composition, further comprising 3 to 22 parts by weight of aluminum dross. 3 to 42 parts by weight of EAF dust, 5 to 35 parts by weight of coal ash, 15 to 55 parts by weight of stone powder and 5 to 45 parts by weight of sewage sludge incineration. Aggregate composition. The method of claim 4, wherein A lightweight aggregate composition, further comprising 3 to 17 parts by weight of aluminum dross. The method of claim 4, wherein The composition for light weight aggregates, further comprising 5 to 35 parts by weight of red mud. Combining at least two or more wastes selected from the waste group consisting of coal ash, EAF dust, steel slag, sewage sludge incinerator, stone flour, paper sludge incinerator and aluminum dross according to each chemical composition; Adding clay to the waste to form a mixture; Filter pressing the mixture to form a filter cake; Aging the filter cake; Primary molding the filter cake to form a first molded body; Forming the second molded body by second molding the first molded body; Drying the second molded body; Sintering the dried second molded body to form a sintered body; And Cooling the sintered body to form a composition for lightweight aggregate comprising the step of forming a composition for lightweight aggregate. The filter cake is light weight aggregate composition, characterized in that having a water content of 20 to 25 percent (%). The method of claim 7, wherein Forming the first molded body is a lightweight aggregate composition, characterized in that further comprising the step of cutting the first molded body to a predetermined size. The method of claim 7, wherein The second molded body is formed while passing through the tub that rotates the first molded body at a predetermined speed, the composition for light weight aggregates.