KR100290647B1 - Manufacturing method of calcium aluminosulfate-based expandable material - Google Patents

Abstract

The present invention relates to an aluminum scrap (hereinafter, referred to as "Al" aluminum) (Al foil, cans, thin plates, etc.), an Al dissolution plant dust and dust or Al ₂ O ₃ x H ₂ O and quicklime, (Sludge) {abandoned sludge of limestone plant and waste material [Ca (OH) ₂ ] after producing asecylene gas with carbide (CaC ₂ )} and calcium aluminosulfate system (Ca-Al-SO-based), the 3CaO.Al2O ₃ .3CASO _4-based (also known as CAS also referred to as expandable material) that relates to a process for the preparation of expandable material bangbeo, Al sheet scraps, Al plate, waste packaging and disposable aluminum plant as a representative compound In the case of recovering Al by dissolving waste dust and dross, the recovery rate of Al is extremely lowered, so that it is discarded or partially used. In addition, most of the limestone in the limestone calcining plant is discarded, and also the carbide (CaC ₂ ) waste material after the manufacture of gas and I is Ca (OH) ₂ But the problem of causing pollution by that is discarded in a state, and the present invention, the melting of Al by dissolving a bad Al thin foil system scrap recovery, Al dross and waste dust or Al ₂ O ₃ xH ₂ O with sulfuric acid and I The calcium aluminosulfate-based expanding material is then added by adding any of lime, limestone sludge, or carbide waste material to recover precious resources and at the same time to solve the pollution problem, and the expanding material produced by the present invention can be used as a rock or concrete structure It is difficult to use gunpowder to remove structures and rocks in the city. However, calcium aluminosulphate-based expanding materials are used as explosive materials which can be destroyed without sounding and vibration It can be used as an explosive, and it also controls the shrinkage expansion of concrete, crack prevention and compressive strength It can be used as an improving agent. It can be used as control for shrinkage expansion, crack prevention and hardening agent mixed with clay soil, and it has various uses such as waterproofing agent and water purification agent. Therefore, when an expander is manufactured using these materials, As a result, it can exert tremendous profits on the economic side and can handle the pollution on the environmental aspect. Therefore, it has a remarkable effect such as contributing greatly to the preservation of the factory environment and natural environment, and greatly improving the economic profit.

Description

Manufacturing method of calcium aluminosulfate-based expandable material

The present invention relates to a process for producing a calcium aluminosulfate-based expanding material from waste aluminum scrap, waste Al dross or waste Al dust and lime or waste lime slag, (Al) scrap, waste Al dross or waste Al dust containing metallic Al is dissolved in sulfuric acid, and then CaO, Ca (OH) ₂ or waste stone sludge (waste sludge of limestone calcining plant (CaO-Al ₂ O ₃ -CaSO ₄ ) is synthesized by wet synthesis at a predetermined temperature, concentration, and a predetermined time by adding any of CaCO ₃ or waste sludge after the production of acacylene to carbide) Then, the calcination is performed in the range of 500-1200 ° C. However, the production method of the present invention is not limited to the method of recovering waste resources and recycling resources, thereby creating a great added value and protecting the natural environment Number It is about the cleansing technology.

Korea currently depends on imports of explosives, explosives and building and civil engineering expansion materials. Existing methods of manufacturing this expanding material, CaO-Al ₂ O ₃ -CaSO ₄ (hereinafter referred to as "CAS"), ₂ O ₃ .3H ₂ O), lime (CaO, Ca (OH) ₂ , CaCO ₃ ) and CaSO ₄ H ₂ O are mixed in an appropriate amount by stoichiometric calculations and calcined at 1100-1300 ° C. Is poor and the particle size is large, and the refractory consumption is high, the fuel is large and the inflatability is weak.

The method of manufacturing by this dry method is as follows: the Onoda cement production method of JP-B No. 97-003941 (970324), JP 226987 (861014), clay, limestone and gypsum are well mixed and then fired at 1100-1300 ° C to produce CAS JP54029326 discloses a method for mixing CaO with Al ₂ O ₃ and CaSO ₄ 2H ₂ O and JP 78016007, JP 78038290 or 3Ca0.Al ₂ O ₃ for mixing and calcining at a high temperature JP 53085822 has been disclosed. Examples of the present industrialization include a dry method of mixing calcite and limestone and gypsum at a high temperature in Japan, such as electrochemical industry Co., Ltd., Yoshizawa coal Co., Ltd. and Onoda Cement Co., Ltd. .

However, the method of recovering aluminum by melting Al thin-plate scrap has a low recovery rate and can not be used as an effective utilization method of scrap. In the case of the discarded Al Dask, And the waste generated from the sludge and carbide produced in the limestone calcining plant are also polluted. Therefore, there is a great problem in the environmental screen .

In order to solve the above-described problems, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method of drying a waste alkyd dust, Al ₂ O ₃ .3H ₂ O, sulfuric acid, lime or limestone, This method is a completely different method from the existing technology. Especially, it is a method of manufacturing polluterous waste as raw material. Therefore, Korea, which relies only on import of Al raw material, Since the characteristics are significantly different from those of the conventional methods and the conventional wastes contain a manufacturing component of 3CaO.Al ₂ O ₃ .3CaSO ₄ (CAS) as a raw material, the CAS expander is manufactured using the above materials as raw materials The purpose of this study is to provide a method of manufacturing an expandable material that can save natural environment by collecting resources, creating added value and polluting the disclosure.

The object of the present invention is to provide a method for producing a water-absorbent resin, which comprises the steps of dissolving Al in sulfuric acid, adding a stoichiometric amount of lime, lime and the like to the aqueous solution, ≪ / RTI > CAS was prepared,

A method for producing a CAS expander by burning hydroxides at 500 to 1200 ° C according to the above formula can be accomplished by the present invention, which will be described in detail with reference to the accompanying drawings and an electron micrograph.

1 is a representative X-ray diffraction analysis chart showing experimental results of Table 3 according to the first embodiment

2 is a representative X-ray diffraction analysis chart showing the experimental results of Table 5 according to the second embodiment

3 shows X-ray diffraction diagrams of 3CaO.Al ₂ O ₃ .3CaSO ₄ produced by calcination of various hydroxides

FIG. 4 is an electron micrograph of CAS prepared by a synthetic experiment

5 is an electron micrograph of the CAS calcined at each temperature

FIG. 6 is an electron micrograph obtained by hydrating and calcining calcined CAS at each temperature

7 is a flowchart

Fig. 7 shows a process chart of the present invention.

The method for producing a calcium aluminosulfate-based expansion material according to the present invention comprises dissolving waste Al dust, waste Al dross, scrapped Al scrap or Al ₂ O ₃ .3H ₂ O in a 25-50% aqueous H ₂ SO ₄ solution, Mixing the aqueous solution of Al ₂ (SO ₄ ) ₃ and the lime compound in an amount based on stoichiometric calculations, charging the mixture into a stainless steel vessel equipped with a stirrer and a heater, The reaction was carried out by wet process from normal pressure to 70 캜 and the reaction time was about 60 minutes to obtain a synthesized compound {xCaO.Al ₂ O ₃ .3CaSO ₄ .yH ₂ O (x = 1, _{3, 4,} , 16, 18, 21, 24, 25, 26, 27)}, drying the compound thus synthesized and charging it into a heating furnace, calcining the mixture at about 500 to 1200 ° C for about 60 minutes, , And crushing and packaging the calcined CAS.

An analytical table of the Al sample used in the present invention is shown in Table 1, an analytical table of the lime sample is shown in Table 2, and an expander was prepared using 96% H ₂ SO ₄ as sulfuric acid.

[Table 1]

[Table 2]

1 kg of each of the Al samples shown in Table 1 was diluted to 1, 25, 30, 40, and 50% with respect to the metal Al content, and then added to each H ₂ SO ₄ aqueous solution Leaching reaction at 70 ~ 80 ℃ for 2 ~ 8 hours at atmospheric pressure resulted in the leaching rate of Al exceeding 80%. Near the concentration of the aqueous sulfuric acid solution solvent, _{25% Al 2 O 3. 3H 2} O showed that more than 80% within two hours, the leaching rate, the lung is dust Al showed 80% or more leaching yulreul within 3 hours at a concentration of at least 30% sulfuric acid , When Al was dissolved in an aqueous solution of 50% sulfuric acid, H ₂ gas was generated in a large amount and the temperature rapidly increased, so that the water quickly evaporated. At this time, the leaching rate was improved to 90%.

The chemical analysis table of the lime samples used as the synthetic agent is shown in Table 2.

The Al ₂ (SO _{4) 3} aqueous solution prepared as above, Al ³⁺ 2.5gr / ℓ as Ca (OH) ₂ CaO pulp 20gr / ℓ to the one prepared in 50 ℃ formula (6) Al ³⁺ 5gr / ℓ and CaO 40gr / l pulp was synthesized at 50 ℃ and the reaction of Al3 ⁺ 7.5ge / ℓ and CaO 60gr / ℓ pulp at 50 ℃ was as shown in Eq. (8).

The above reactions are synthesized at 30 minutes under atmospheric pressure. These equations can be defined as follows: 10 g of the sample dried at 90 ° C. was synthesized in the formulas (6) to (8) and calcined at 1000 ° C. for 1 hour to calculate the water evaporation amount, Weight loss, equation (7) showed 26% weight loss, and equation (8) showed 30% weight loss.

Therefore, it can be expressed as the following.

The results of the X-ray diffraction analysis of the compounds synthesized as described above and dehydration and drying are shown in FIG. 1 and FIG. 2, and the results of electron microscopic investigation are shown in FIG. As shown in the photograph, the particle size is less than 10 μ and the shape is spherical, columnar, needle-shaped. Generally, it shows a columnar or acicular shape at low temperature and a spherical shape at high temperature. As a result of heating at 500, 800, 1000, 1100 and 1200 ℃, the dehydration rate reached 90% at 500 ℃, but the dehydration rate was 97 %. The heating reaction time was from 1 hour to 6 hours, but the difference in dehydration rate was not significant at over 1 hour. An example of the calcination reaction at the time of heating can be represented by the following equation (9).

3CaO.Al ₂ O ₃ .3CaSO ₄ .18H ₂ O 3CaO.Al ₂ O ₃ .3CaSO ₄ + 18H ₂ O ↑ ... ... ... ... ... ... (9)

3CaO.Al ₂ O ₃ .3CaSO ₄ (CAS) produced by calcination as shown in the formula (9) is pulverized and pulverized in a pulverizer to 10 μ or less (see the electron micrograph of FIG. 6).

The chemical composition of CAS can be determined by measuring the Al ₂ (SO ₄ ) ₃ aqueous solution, CaO, Ca (OH) 2, and CaO as shown in the X-ray diffraction charts (FIGS. 3A, 3B, ₂ , and CaCO ₃ , respectively. Thus, it can be seen that CAS is produced regardless of the synthesis of lime.

FIG. 6 is a graph showing the results of the electron micrograph of FIG. 5 in which samples calcined at 500, (B) 1000, (C) 1000 and (D) And dried at 90 DEG C for 24 hours, and then photographed under an electron microscope. As shown in FIG. 6, it is shown that the size of particles increases greatly.

Some experimental examples are shown in Tables 3, 4 and 5.

[Table 3]

[Table 4]

The first example in Table 3 is the result of experiment with varying CaO composition as the following equations (10) to (12).

As shown in the above formula and Table 3, when the CaO content is high, the water content is increased and the production amount is increased. It was found from the X-ray diffraction analysis of FIG. 2 that a sample having a high CaO content and a high water content, and a structure like a columnar particle in the electron micrograph of FIG. 4 were produced.

[Table 5]

The second embodiment of Table 4 is the result of an experiment under the conditions of Example 1 in which Ca (OH) ₂ sludge and CaCO ₃ sludge were mixed at a ratio of 1: 1.

As shown in the table, the results of X-ray diffraction analysis similar to that of the first embodiment are shown in Figs. 1 and 2, and the electron microscopic structure is shown in Fig. The reaction equation can be expressed as follows.

3Ca (OH) ₂ + 3CaCO ₃ + Al ₂ (SO ₄ ) _3. 18H ₂ O = 3CaCO ₃ .Al ₂ O ₃ .3CaSO ₄ .21H ₂ O (13)

The results of X-ray diffraction analysis of a sample calcined at 1100 DEG C for 60 minutes at 20 gr of the compound obtained in the experiment of Table 4 (see Equation 13) are shown in Fig. 3 (D) , And (C), it is considered that the reaction formula can be expressed by the following equation (14).

_{3CaCO 3. Al 2 O 3 .3CaSO 4.} 21H 2 O → 3CaO.Al 2 O 3 .3CaSO 4 + 21H 2 O ↑ + 3CO 2 ↑ ...... (14)

As a third embodiment of Table 5, results of calcination experiments are presented. As shown in the table, 3CaO _. Al ₂ O ₃ .3CaSO _4. 18H ₂ O by temperature As shown in the experimental results, the dehydration efficiency was over 90% at 500 ° C or higher and the dehydration rate at 1000 ~ 1200 ° C 99 or more.

The X-ray diffraction analysis results showed the same composition as (A) and (B) in FIG. 3, and the electron microscopic structure was similar to FIG. As shown in the electron micrograph, the particle size of the expandable material can be controlled to be less than 1 μ and to less than 10 μ .

As shown in the above examples and each of the formulas presented, there is a feature of manufacturing an expandable material by arbitrary control based on the stoichiometric calculation according to the properties of the expandable material.

The invention, xCAS.yH ₂ O (x = y = 1,3,4,5,6 14,16,18,21,24,25,26,27) of metallic aluminum, sulfur, lime or limestone in a wet And then firing at 500 ~ 1200 ° C. This is a completely different method from the existing technology, and has the following effects.

First technical aspect;

(1) The CAS expanding material is produced by calcining after CAS hydrate is synthesized by a chemical method. Therefore, since the produced particles are produced as ultrafine powder, the quality is excellent and the pulverization ratio is less than that of the dry method.

(2) The calcining temperature of the expanding material is CaO, Al ₂ O ₃ and CaSO ₄ 2H ₂ O mixed in the dry method, and CAS particles are grown at a high temperature around 1300 ° C., xCAS.yH ₂ O described above at a temperature of less than ℃ saving process of manufacturing because it is a step of adjusting a particle size while removing only the water was (x and y are as defined above) is synthesized from more than 500 ℃ (up to 1200 ℃) fuel to be.

Second, economic and environmental aspects;

Since this expanding material is manufactured by using polluterous waste as a raw material, Korea, which relies only on the import of Al raw material, is different from the conventional method in that it can also collect pollutant as well as recover resources, which is a problem in the past wastes produced when the CAS expandable material to said material as a raw material because it contains the components of the manufacturing _{xCaO, Al 2 O 3. 3CaSO 4.} 2 (x = 1,3,4,5,6) (CAS) with expandable material It is possible to save natural resources by collecting resources, creating added value, and polluting the environment.

Claims (1)

Producing an aqueous solution of aluminum sulfate to dissolve waste Al dust, scrapped Al scrap or Al ₂ O ₃ .3H ₂ O in a 25-50% sulfuric acid aqueous solution; A predetermined liquor (pulp) is prepared by charging the above-mentioned aqueous solution of aluminum sulfate into a stirring tank of any one kind or mixture of slaked lime, quick lime, limestone, or a waste slurry of a carbide plant or a limestone calcining plant, The aqueous solution of Al ₂ (SO ₄ ) ₃ and the calcium-based pulp were added together in a reaction vessel equipped with a stirrer and a heating device by stoichiometric calculation so as to be in accordance with the composition of the expander requiring this pulp, minutes before and after allowing to react _{xCaO.Al 2 O 3 .3CaSO 4 yH 2} O (x = 1,3,4,5,6 y = 14,16,18,21,24,25,26,27) process for synthesizing and; The above-mentioned synthetic compound was dehydrated, dried at about 90 ° C., charged into a heating furnace, and calcined in the temperature range of 500, 800, 900, 1000, 1100, 1200 ° C. for 1 hour to 4 hours depending on the use of the product. Thus, xCaO.Al ₂ O A step of producing an expander of ₃ .3CaSO ₄ (x = 1, _{3, 4, 5,} 6) by a wet-dry method; And finely pulverizing the expandable material to 10 占 퐉 or less and packaging the expanded calcium aluminosulphate expandable material.