KR100650545B1 - Water treating composition using the aluminium dross - Google Patents

Abstract

In the present invention, aluminum sulfate and polyaluminum chloride (PAC), which are used as water treatment coagulants, are prepared by using aluminum dross, which is an oxide layer formed on the surface of a molten metal when dissolving aluminum metal or scrap. After the first preparation, it was filtered in a filter press, and the leach residue after filtration was washed with water and dried, and then the residue was fed at a rotary kiln at a rotary feed rate of 70 grams per minute at 900 ^o C, and roasted for 1 hour. Mixed with residue, alumina cement, aggregate and water, cured in molding mold and cured at room temperature for 22 hours for 24 hours, dried in oven for 10 hours or more, and then baked at 1350 ^o C to recycle aluminum dross. It relates to a manufacturing method of.

Aluminum dross. Castable ceramic.

Description

Water treating composition using the aluminum dross

In the present invention, aluminum sulfate and polyaluminum chloride (PAC), which are used as water treatment coagulants, are prepared by using aluminum dross, which is an oxide layer formed on the surface of a molten metal when dissolving aluminum metal or scrap. After the first preparation, it was filtered in a filter press, and the leach residue after filtration was washed with water, dried, and then the residue was fed at a rotary kiln at a rotary kiln at a rate of 70 grams per minute at 900 ^o C, prepared by roasting for 1 hour. Mixed with residue, alumina cement, aggregate and water, cured in molding mold and cured at room temperature for 22 hours for 24 hours, dried in oven for 10 hours or more, and then baked at 1350 ^o C to recycle aluminum dross. It relates to a manufacturing method of.

Since aluminum is a well oxidized metal, aluminum dross is always generated whenever or when aluminum is dissolved. The aluminum dross is removed from the melting furnace when casting to the now after melting, and some remain in the melting furnace or crucible when the aluminum molten metal is poured into the mold, and is generated in a molten runner during the casting of the molten metal.

In Korea, in the conventional case, an aluminum melting company heats aluminum dross to melt it first or second, thereby reducing the amount of dross to be recovered and discarded aluminum metal in the dross. Or it is a common way to landfill by consignment. The final waste dross produced is mostly aluminum oxide, which is often mixed with 10-35% metallic aluminum, less than 10% salt, and impurities such as Mg, Si, Fe, etc. originally present in Al scraps. .

In the case of treating the aluminum dross according to the conventional method, the cost of securing the landfill or the aluminum dross processing cost of entrusting the waste disposal company is required. Therefore, in the present invention, by using a sulfuric acid and hydrochloric acid solution to reduce the treatment cost of aluminum dross and environmental pollution through a recycling method of leaching and separating the aluminum metal in aluminum dross into a solution to recover the aluminum sulfate or polyaluminum chloride. I wanted to prepare a plan.

Conventional methods for preparing aluminum sulfate are made by using aluminum hydroxide (Al (OH) ₃ ) as a raw material, which is prepared by reacting sulfuric acid with aluminum hydroxide, and the conventional method for preparing polyaluminum chloride is based on sulfuric acid, which is a catalyst for aluminum hydroxide. Hydrochloric acid is added together to react at 150-180 _^o C temperature and 3-5kg / cm ² pressure, calcined lime (CaO) is added to the reaction solution to precipitate sulfuric acid with gypsum, and the solution is filtered to prepare polyaluminum chloride. Using is the common way.

Korean Patent Laid-Open Publication No. 2002-0039274 discloses a technical configuration for producing polychloride silicate and polysulfate silicate using aluminum materials.

Published Japanese Patent Publication No. 1998-65600 discloses waste aluminum in which aluminum dross is crushed, the classification process is carried out, and then the large particles which have not passed the classification process are re-dissolved to change the metal components of the waste aluminum dross into oxides. Roth's reprocessing method is described,

Korean Patent Publication No. 10-0278777 discloses a technique of crushing aluminum dross, leaching with caustic soda solution, filtering to recover aluminum hydroxide, and roasting the residue to produce an alumina castable refractory.

The prior art as described above has a problem in that the operating cost for maintaining high temperature and high pressure during roasting is expensive, and the aluminum recovery rate is not high, so it is not practical to use for economic reasons.

In order to solve the above problems, the present invention breaks down aluminum dross and classifies it according to size, and then re-dissolves the large particles in a crucible furnace to recover aluminum metal, and the small ones are leached into sulfuric acid solution to make aluminum An aluminum sulfate solution was prepared by dissolving the aluminum component in the dross into a sulfuric acid solution, and leaching it with hydrochloric acid solution instead of sulfuric acid to dissolve the aluminum component in the aluminum dross into a hydrochloric acid solution. The polyaluminum chloride solution was prepared. The alumina sulfate and polyaluminum chloride solution were prepared by filtration to adjust alumina concentration and basicity to meet KS standards by adding water and soda aluminate. In addition, it is a technical task of the present invention to provide a ceramic recycled aluminum dross that is washed with water, then dried, roasted and recycled as a ceramic raw material or landfill.

In order to achieve the above object, the present invention uses aluminum dross, which is an oxide layer formed on the surface of the molten metal when dissolving aluminum metal or scrap, and aluminum sulfate (Alum) and polychloride which are used as water treatment coagulants. After preparing aluminum (PAC: Poly Aluminum Chloride) first, it is filtered on a filter press, and the leach residue after filtration is washed with water and dried, and then residues of 20 mesh or less (waste aluminum dross) are removed from a rotary kiln. The feed rate is 70 grams per minute, and then mixed with residue (waste aluminum dross), alumina cement, aggregate, and water, prepared by roasting at 900 ^o C for 1 hour, curing at room temperature for 22 hours after molding in molding mold. After drying for 10 hours or more in an oven for 10 hours, and firing at a temperature of 1350 ^° C relates to a method for producing a ceramic recycled aluminum dross.

Aluminum dross used in the present invention (aluminum ash) is produced in the domestic aluminum recycling now manufacturers, in the present invention mainly aluminum dross generated after recovering aluminum metal by primarily dissolving aluminum dross in the aluminum recycling company. Was treated as.

The main principle of the process is to break the aluminum dross, so that the larger particles contain more metal and the smaller particles contain more oxides, so the larger particles are re-dissolved in a crucible furnace, etc. The small particles are recovered by leaching with sulfuric acid and hydrochloric acid solution to separate the aluminum metal in aluminum dross into the solution, to prepare aluminum sulfate or polyaluminum chloride first, and then extract the residue to form aggregates and roast the ceramics. To manufacture.

In the present invention, when the aluminum dross is crushed, the metal component in the aluminum dross is deformed, but the particles are made larger, whereas the oxides are broken and the particles are smaller. The smaller is, the more oxide is present. Therefore, large particles can directly recover Al metal through remelting.

In classification, the sieve was sieved using an 18 mesh Taylor standard mesh. If the aluminum dross particle size is undersize smaller than 18mesh (1mm size), the aluminum metal is intercalated between the aluminum dross particles during dissolution so that it cannot be melted and casting is difficult. It is difficult to recover aluminum. The classification process divides aluminum dross by size and treats aluminum dross less than 18mesh where aluminum metal is not obtained, and uses it for recycling process, and it dissolves only those having size of 18mesh or more to increase the dissolution efficiency and decrease the dissolution amount of aluminum dross. This is to reduce the amount of aluminum dross generated. Crushing was carried out using a rod mill, and a melting furnace or crucible furnace was used for melting.

The main components of aluminum dross are aluminum oxide or alumina and metallic aluminum. Aluminum oxide exists in the form of α-alumina, β-alumina, γ-alumina, etc. according to the temperature and growth process of crystal growth in nature, and aluminum oxide is often present in the form of α-alumina. Al is an amphoteric element that has a property of being soluble in acid or alkali, whereas aluminum oxide is less soluble than aluminum and alpha alumina is more difficult to dissolve than gamma alumina.

Therefore, when leaching aluminum dross with sulfuric acid, the Al metal component in the dross reacts with sulfuric acid to leach into the solution and the oxide remains in the leaching residue.

   When leaching aluminum dross with sulfuric acid, the chemical reaction in the solution is given by the following equation (1). In Formula (1), Al represents the Al component remaining in aluminum dross.

2 Al + 3 H ₂ SO ₄ --- ▶ Al ₂ (SO ₄ ) ₃ + 3 H ₂ ↑ ... (1)

Filtration of the reaction product of formula (1) yields a solution of aluminum sulfate (Al ₂ (SO ₄ ) ₃ ), which is then water-added to adjust the alumina concentration of the solution to meet the needs of the consumer. do. The residue generated during filtration is washed, dried, roasted, and then recycled or landfilled into ceramic raw materials such as ceramics after detoxification.

In addition, when manufacturing aluminum sulfate by reacting aluminum hydroxide with sulfuric acid as in the prior art, water is generated as shown in the following formula (2),

2 Al (OH) ₃ + 3 H ₂ SO ₄ --- ▶ Al ₂ (SO ₄ ) ₃ + 6 H ₂ O ... (2)

In the case of leaching aluminum dross with sulfuric acid as in the present invention, hydrogen gas is generated as a by-product as shown in Equation (1), and the hydrogen gas may be collected separately and used for producing hydrogen gas or hydrogen compound for fuel.

Next, when hydrochloric acid (HCl) is added to aluminum dross, aluminum reacts with hydrochloric acid to produce aluminum chloride (AlCl ₃ ) as shown in Equation (3). This aluminum chloride is a polyaluminum complex compound called polyaluminum chloride (PAC). In Formula (3), Al represents the Al component remaining in aluminum dross.

2 Al + 6 HCl --- ▶ 2 AlCl ₃ + 3 H ₂ ↑ ... (3)

Filtration of the reaction product of formula (3) yields a polyaluminum chloride solution (PAC), which is then dissolved in water and caustic soda (NaOH), sodium phosphate (NaAlO ₂ ) or sodium silicate (Na ₂ SiO _3). ) Add the solution and adjust the alumina equivalent and basicity of the solution according to the product standard (KS standard) to commercialize it as a PAC product. The residue (waste aluminum dross) generated during filtration is recycled or landfilled after desalination through washing, drying and roasting.

Hereinafter, the present invention will be described in detail with reference to the following Examples.

Example 1

Step 1 (Manufacture of Aluminum Sulfate)

The aluminum dross produced during the melting of the scrap is first melted, and the particle size of the aluminum dross is larger than about 1 mm to redissolve the aluminum metal to recover the aluminum metal. When recovering the residual aluminum by first melting the loss

In the reaction tank, 98% sulfuric acid (specific gravity 1.84) and aluminum dross were adjusted to a sulfuric acid / Al equivalent ratio of 0.7-0.9 with respect to the metal Al in the aluminum dross, and the solution of aluminum in the aluminum dross was stirred at 80 ^° C. for 3 hours. Leaching in to produce an aluminum sulfate solution. This is filtered through a filter press,

2nd process (ceramic manufacturing)

After filtration, the leach residue was washed with water, dried, and then residues of 20 mesh or less (waste aluminum dross) were prepared by roasting 900 ^o C for 1 hour at a rotary kiln of 70 grams per minute. 10.5 ~ 15kg Aggregate (2.0-4.0mm) 40kg thick, medium (0.074-2.0mm) 30kg, fine (0.074mm or less) 1-15kg by mixing the appropriate amount of water (see Table 7) ), After molding in a molding mold was cured for 24 hours at 22 ^° C room temperature, dried at 110 degrees or more in an oven for 10 hours, and then calcined at 1350 ^° C to produce a ceramic dross recycled aluminum.

Example 2

First step (Production of poly aluminum chloride (PAC))

Charge 30% hydrochloric acid (specific gravity 1.15) and aluminum dross into the reaction tank and leach aluminum in aluminum dross into the solution while stirring for about 3 hours to prepare an aluminum chloride solution, and then filter it on a filter press. the fixed and 18kg, was adjusted with hydrochloric acid and the hydrochloric acid water jangipryang / Al equivalent ratio such that from 0.6 to 0.7, oxygen almin come to control the basicity and the degree of polymerization of aluminum chloride (NaAlO ₂₎ with respect to a solution of 100ml 2-3.5ml After further reaction to prepare a polyaluminum chloride (PAC). This is filtered through a filter press,

2nd process (ceramic manufacturing)

After filtration, the leach residue was washed with water, dried, and then residues of 20 mesh or less (waste aluminum dross) were prepared by roasting 900 ^o C for 1 hour at a rotary kiln of 70 grams per minute. 10.5 ~ 15kg Aggregate (2.0-4.0mm) 40kg thick, medium (0.074-2.0mm) 30kg, fine (0.074mm or less) 1-15kg by mixing the appropriate amount of water (see Table 7) ), After molding in a molding mold was cured for 24 hours at 22 ^° C room temperature, dried at 110 degrees or more in an oven for 10 hours, and then calcined at 1350 ^° C to produce a ceramic dross recycled aluminum.

Experimental Example 1 Preparation of Aluminum Sulfate from Aluminum Dross

The aluminum dross used in the experiment was generated by a domestic aluminum recycling now manufacturer, and the aluminum dross produced after partially dissolving aluminum dross generated by dissolving aluminum dross generated during scrap dissolution. Chemical composition of aluminum dross was quantitatively analyzed by element using ICP. The results of the component analysis of the small elements other than Al are shown in Table-1. Metal aluminum remains in the aluminum dross. The metal Al content of the aluminum dross varies depending on how much metal Al is recovered when the aluminum dross is first dissolved to recover the residual aluminum. In this example, a metal Al content of 30wt% was used as a sample.

            Table 1. Results of quantitative analysis of aluminum dross by element.

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      Component Mg Mn Fe Zn Ca K Na Al

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      wt% 3.85 0.15 1.54 0.82 1.86 0.47 0.80 res.

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The leaching experiment was carried out by charging 98% sulfuric acid (specific gravity 1.84) and aluminum dross in a reaction tank and leaching aluminum in the aluminum dross into the solution while stirring at 80 ^° C. for 3 hours to prepare an aluminum sulfate solution. In order to filter, the amount of aluminum dross was fixed to 18 kg through the entire experiment, and the amount of sulfuric acid and water was adjusted to match the alumina (Al ₂ O ₃ ) concentration and the pH of the solution in the aluminum sulfate product standard set by KS.

Based on the above formula (1), the weight of 1 equivalent of 98% sulfuric acid per 1 equivalent of aluminum is as shown in the following formula (4). Where W _Al is the metal Al content in the aluminum dross, W _{H 2 SO 4} is the weight of 98% sulfuric acid to be charged and M is the molecular weight of aluminum and sulfuric acid. Since the Al content in the sample dross is 30%, the weight of the metal aluminum is 5.4 kg when the amount of aluminum dross is 18 kg as in this experiment, and the weight of 1 equivalent of 98% sulfuric acid is 30 kg.

W _H2SO4 = (W _Al x (3M _H2SO4 / 2M _Al )} / 0.98 ... (4)

The main specifications of aluminum sulfate specified by KS are 8 wt% or more of Al ₂ O ₃ concentration, pH 3.0 or more of solution and specific gravity 1.3 or more, so that 0.6-1.0 equivalents of sulfuric acid can be used per 1 equivalent of aluminum to produce aluminum sulfate in this standard range. Six tests were carried out using the amount of sulfuric acid and water in the range as shown in the following Table 2, and the results of the characterization of the test manufactured aluminum sulfate were shown together. The alumina content was analyzed according to the Ministry of Environment No. 2004-95.

  Table 2. Test result of manufacturing aluminum sulfate

Exam number Al dross loading, kg Sulfuric acid / Al equivalence ratio 98% sulfuric acid loading, kg Water loading, kg  Test article characteristics % Al ₂ O ₃ pH importance One 18 0.6 18 91 7.8 3.9 1.286 2 18 0.7 21 88 8.03 3.5 1.292 3 18 0.8 24 85 8.06 3.3 1.304 4 18 0.9 27 82 8.07 3.1 1.306 5 18 1.0 30 79 8.07 2.8 1.312 6 18 1.1 33 76 8.08 2.3 1.318

From the above results, when the sulfuric acid / Al equivalent ratio was in the range of 0.7-0.9, the physical properties such as% Al ₂ O _3, pH, and specific gravity were satisfied by KS. In case of less than this range, the% Al ₂ O ₃ content was smaller than the standard. In case of greater than this range, the pH of the solution is out of specification. Through such an embodiment, when the sulfuric acid / Al equivalent ratio is 0.7-0.9 with respect to the metal Al in the aluminum dross, aluminum sulfate conforming to the KS standard may be manufactured.

Experimental Example 2 PAC (polyaluminum chloride) production experiment from aluminum dross

In the Experimental Example 2 for producing polyaluminum chloride, the same aluminum dross sample as the Experimental Example 1 was used.

The leaching experiment was carried out by charging 30% hydrochloric acid (specific gravity 1.15) and aluminum dross in a reaction tank and leaching aluminum in aluminum dross into the solution while stirring for about 3 hours to prepare an aluminum chloride solution, which was then filtered on a filter press. Through the experiments, the amount of aluminum dross was fixed at 18 kg, and the amount of hydrochloric acid and water was adjusted to match the alumina (Al ₂ O ₃ ) concentration and the pH of the solution in the polyaluminum chloride product standard determined by KS. In order to control the degree of polymerization and sodium hydroxide, sodium phosphate or sodium silicate was added. In this experiment, sodium phosphate (NaAlO ₂ ) was added to _2- ml of 100 ml of solution.

Based on the above formula (3), the weight of 1 equivalent of 30% hydrochloric acid relative to 1 equivalent of aluminum is as shown in the following formula (5). In this equation, W _Al is the metal Al content in the aluminum dross, W _HCl is the weight of 30% hydrochloric acid charged and M is the molecular weight of aluminum and hydrochloric acid. Since the Al content in the sample dross is 30%, the weight of the metal aluminum is 5.4 kg and the weight of 1 equivalent of 30% hydrochloric acid is 73 kg when the aluminum dross loading is 18 kg as in this experiment.

W _HCl = {W _Al x (3M _HCl / M _Al )} / 0.3 ... (5)

The main specifications of poly aluminum chloride (PAC) prescribed by KS are 10.0-11.0wt% Al ₂ O ₃ concentration, pH 3.5-5.0 of solution and basicity of solution range 45-60. In order to manufacture polyaluminum chloride in this standard range, four tests were performed as shown in Table 3 by adopting the amount of hydrochloric acid and water in the range of 0.5-0.8 equivalents to 1 equivalent of aluminum. The characteristics were analyzed and the results are shown in Table 3 together.

  Table 3. Aluminum Chloride Test Results

Exam number Al dross loading, kg Hydrochloric acid / Al equivalent ratio 30% hydrochloric acid loading, kg Water loading, kg  Test article characteristics % Al ₂ O ₃ basicity pH One 18 0.5 36.5 38 9.7 58 4.6 2 18 0.6 43.7 31 10.2 57 4.2 3 18 0.7 51.0 24 10.8 55 3.9 4 18 0.8 58.3 17 11.2 53 3.3

Was a hydrochloric acid / Al equivalent ratio From the above results meet the specifications prescribed in physical properties such as a KS of from 0.6 to 0.7 in the range% Al ₂ O _{3 ,,} pH and basicity, than if less than this range, the Al ₂ O ₃ content of this specification% Small, and larger than this range, the pH of the solution was out of specification. Through such an embodiment, it is possible to produce polyaluminum chloride that meets the KS standard in the hydrochloric acid / Al equivalent ratio of 0.55-0.75 relative to the metal Al in the waste dross.

Experimental Example 3 Ceramic Preparation from Residue (Waste Aluminum Dross)

In the leaching process of Experimental Examples 1 and 2, the aluminum component in the aluminum dross was separated, and the leach residue after filtration was washed with water, dried and roasted. Roasting is a process for converting metal components such as aluminum and magnesium in the residue (waste aluminum dross) into oxide. The roasting of 20 mesh or less is rotated at 900 ^o C for 1 hour at rotary kiln. 70 grams per minute.

The results of quantitative analysis of the aluminum metal components in the sample after roasting are shown in Table 5. After roasting, the metallic aluminum is 0.61%, which is present in a very small amount compared to the raw material. Table 6 shows the composition of the roasted residue in terms of oxide content. Therefore, most of the metal components including Al in the waste residue can be converted to oxide form through roasting, and the roasted residue can be recycled to other ceramics such as ceramics.

Table 5. Al content in residue after roasting.

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Sample Type After Raw Material Roast

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Al, wt% 34 0.61

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             Table 6. Component (wt%) of residue after roasting.

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SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO MgO K ₂ O Na ₂ O TiO ₂ MnO

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1.45 84.46 0.64 0.48 10.0 0.03 1.15 0.78 0.02

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Test ceramics were prepared by mixing residue, aggregate and alumina cement. Aggregates used in the experiment are chamotte-based aggregates, and the main components are SiO ₂ , Al ₂ O ₃ , 3Al ₂ O _{3 ·} SiO _2, etc. (0.074-2.0mm) and fine (0.074mm or less) were classified and used in three kinds, and the alumina cement was used as a commercial product with an alumina content of 50% or more. The roasted residue (waste aluminum dross) was blended as a ceramic raw material by replacing a part of alumina cement for ceramic manufacture or a part of aggregate addition amount. Replaced.

After determining the mixing ratio of the ceramics, the water content during the mixing was measured, and specimens for strength test of the ceramic were prepared according to KS-L-3503, and the compressive strength, bending strength, and rate of change of the ceramics were measured. The specimens were 4 cm long, 4 cm wide, and 16 cm long. The specimens were molded in a mold and cured at room temperature for 24 hours at 22 ^° C, and then dried at 110 ^° C for 10 hours or longer, 1000 ^o C and 1350 ^o C. It was fired at two temperatures.

Table 7 summarizes the raw material compounding ratio of the test manufactured ceramics, and the test results according to KS-L-3503 are shown in Table 8. In Table 5, the AD indicates that the sample replaced a part of the alumina cement, and the CD indicates the sample that replaced the chamotte aggregate, and the number of the sample name indicates the alternative compounding ratio. In addition, for all test samples, the mixing ratio of the aluminum cement serving as the aggregate and the caking agent was based on 85:15, which is a compounding ratio that is widely applied in commercial ceramics. Therefore, in Tables 7 and 8, AD-0 and CD-0 are the same samples, and represent the samples obtained by mixing three kinds of aggregates and alumina cements by reference without adding residue, and AD-10, 20, and 30 are blended in ceramics. 10, 20, 30% of the amount of alumina cement blended to replace the residue, and CD-5, 10, 15 are the samples in which the fine aggregate in the ceramic is replaced by the residue. %, 33, 67, 100% of the sample is replaced. In addition, the pot life in Table 8 refers to the time that has a flowability that can be used after kneading the ceramic blended material.

As a result of measuring the physical property, each sample except AD-30 was within the range of ± 1.0% of the line change specified in KS-L-3511, and the bending strength after drying at 110 ^o C was 25kgf / cm ² or more and the compressive strength was 25kgf / cm ² or more. We are satisfied enough. The measured value, denoted 110 ^° C x 24h in Table 8, represents the physical properties after drying of the castable specimen. When the aluminum dross is recycled to ceramics from the results of Table 8, it is better to substitute for fine aggregates in the ceramic blending material, and it is understood that the blending amount is suitably within 15% of the total amount. In addition, in Table 8 1,000 ^o C, 1,350 ^o line rate and the strength test results of the C is geotinde presented as a reference when using a ceramic produced in the present invention, being a reduction in strength at 1,000 ^o C binder is alumina this is because the cement water is decomposed in the hydrate formed therein as welding strength is reduced, this is fired at 1350 ^o C when the intensity is raised again to the aggregate material are sintered. It can be seen from the above test example that the residue (waste aluminum dross) can be recycled to ceramics by treatment according to the method according to the present invention.

       Table 7. Raw Material Blend Ratios for Ceramics for Testing.

Sample No. Caking ratio (%) Chamotte Aggregate Blending Rate (%) Water addition amount (%) Alumina cement Aluminum dross 4.0-2.0 mm 2.0-0.074 mm 0.074 mm or less AD-0 AD-10 AD-20 AD-30 15.0 10.5 12.0 10.5 -1.5 3.0 4.5 40.0 30.0 15.0 Workability Standards CD-0 CD-5 CD-10 CD-15 15.0 15.0 15.0 15.0 -5.0 10.0 15.0 40.0 40.0 40.0 40.0 30.0 30.0 30.0 30.0 15.0 10.0 5.0- Workability Standards

      Table 8. Physical Properties of Ceramics Tested from Residues.

Characteristic value  Alumina Cement Alternative Sample Aggregate Replacement Samples AD-0 AD-10 AD-20 AD-30 CD-0 CD-5 CD-10 CD-15 Water content (%) 13.0 13.3 13.7 14.0 13.0 14.2 15.4 16.7 Pot life (minutes) 85 80 60 45 85 70 55 40 Curing Strength (kg / cm ² ) Compressive strength bending strength 563 63.2 421 52.7 375 41.0 288 38.6 563 63.2 426 54.0 348 41.8 278 34.0 Rate of change (%) 110 ℃ x 24h 1,000 ℃ x 3h 1,350 ℃ x 3h 0 -0.06 -0.06 -0.03 -0.03 -0.09 -0.03 -0.12 -0.12 -0.03 -0.06 -0.16 0 -0.06 -0.06 -0.03 -0.06 -0.06 -0.03 -0.12 -0.16 -0.03 -0.12 -0.19 Compressive strength (kg / cm ² ) 110 ℃ x 24h 1,000 ℃ x 3h 1,350 ℃ x 3h 270 213 275 239 153 207 151 120 201 122 99 155 270 213 275 225 149 207 194 127 132 143 87 102 Bending Strength (kg / cm ² ) 110 ℃ x 24h 1,000 ℃ x 3h 1,350 ℃ x 3h 50.3 37.5 71.4 38.6 22.3 65.5 30.4 18.7 56.2 18.7 14.0 43.3 50.3 37.5 71.4 37.5 16.4 67.9 30.4 14.0 44.5 25.0 9.4 35.1 Volume specific gravity 110 ℃ x 24h 1,000 ℃ x 3h 1,350 ℃ x 3h 2.05 1.97 1.98 2.01 1.94 1.96 2.00 1.94 1.95 1.99 1.93 1.95 2.05 1.97 1.98 2.02 1.93 1.95 2.00 1.92 1.92 1.95 1.88 1.89 Porosity,% 110 ℃ x 24h 1,000 ℃ x 3h 1,350 ℃ x 3h 18.2 22.2 24.7 19.7 22.4 25.7 20.6 22.3 25.7 21.5 22.6 26.0 18.2 22.2 24.7 19.7 24.0 26.4 21.4 25.9 27.8 23.9 28.3 29.6

As described above, the present invention treats aluminum dross generated during the dissolution of aluminum, and leaches metal aluminum contained in aluminum dross with a sulfuric acid and hydrochloric acid solution to prepare aluminum sulfate and polyaluminum chloride. Compared to the conventional method for producing aluminum sulfate and polyaluminum chloride, the cost of raw materials and fuel can be reduced, and the manufacturing cost of the product can be lowered. Also, when aluminum metal contained in aluminum dross reacts with acid There is also an advantage that the generated hydrogen gas can be recovered as a by-product. In addition, the leaching residue of aluminum dross can be washed, dried, and roasted to be recycled into ceramic raw materials such as ceramic raw materials, thereby significantly reducing the amount of residue (waste aluminum dross) to be disposed of in landfills, thereby reducing the processing cost. At the same time, it is expected to prevent environmental pollution and to be able to apply it as a manufacturing material to related industries.

Claims (4)

In the manufacturing method of the ceramic recycled aluminum dross, Step 1 (Manufacture of Aluminum Sulfate) The aluminum dross produced during the melting of the scrap is first melted, and the particle size of the aluminum dross is larger than about 1 mm to redissolve the aluminum metal to recover the aluminum metal. When recovering the residual aluminum by first melting the loss In the reaction tank, 98% sulfuric acid (specific gravity 1.84) and aluminum dross were adjusted to a sulfuric acid / Al equivalent ratio of 0.7-0.9 with respect to the metal Al in the aluminum dross, and the solution of aluminum in the aluminum dross was stirred at 80 ^° C. for 3 hours. Leaching in to produce an aluminum sulfate solution. This is filtered through a filter press, 2nd process (ceramic manufacturing) After filtration, the leach residue was washed with water, dried, and then residues of 20 mesh or less (waste aluminum dross) were prepared by roasting 900 ^o C for 1 hour at a rotary kiln of 70 grams per minute. 10.5 ~ 15kg by coarse aggregate particle size (2.0-4.0mm) 40kg, medium (0.074-2.0mm) 30kg, fine (0.074mm or less) 1 ~ 15kg by mixing the appropriate amount of water in the molding mold After molding, curing at room temperature 22 degrees for 24 hours, drying at 110 degrees for 10 hours or more in an oven, and then firing at 1350 ^o C temperature to manufacture aluminum recycled ceramics. delete In the manufacturing method of the ceramic recycled aluminum dross, First step (Production of poly aluminum chloride (PAC)) Charge 30% hydrochloric acid (specific gravity 1.15) and aluminum dross into the reaction tank and leach aluminum in aluminum dross into the solution while stirring for about 3 hours to prepare an aluminum chloride solution, and then filter it on a filter press. Was fixed at 18 kg, and the amount of hydrochloric acid and water was adjusted so that the hydrochloric acid / Al equivalent ratio was 0.6-0.7, and any one compound selected from caustic sodium, sodium aldehyde or sodium silicate was adjusted to control the basicity and polymerization degree of polyaluminum chloride . Reaction was performed by adding 2-3.5 ml of the solution to 100 ml of polyaluminum chloride (PAC). This is filtered through a filter press, 2nd process (ceramic manufacturing) After filtration, the leach residue was washed with water, dried, and then residues of 20 mesh or less (waste aluminum dross) were prepared by roasting 900 ^o C for 1 hour at a rotary kiln of 70 grams per minute. 10.5 ~ 15kg by coarse aggregate particle size (2.0-4.0mm) 40kg, medium (0.074-2.0mm) 30kg, fine (0.074mm or less) 1 ~ 15kg by mixing the appropriate amount of water in the molding mold After molding, curing at room temperature 22 degrees for 24 hours, drying at 110 degrees for 10 hours or more in an oven, and then firing at 1350 ^o C temperature to manufacture aluminum recycled ceramics. delete