KR101080855B1 - Preparation method of Eco-building material using waster polishes sludge - Google Patents

Abstract

The present invention relates to a method for manufacturing environmentally friendly building materials using waste abrasive ash sludge discharged from a CRT CRT panel production process.
In detail, eco-friendly building materials can be manufactured by mixing briquette materials, metakaolin and alkaline stimulants with waste abrasive sludge generated in the CRT CRT panel manufacturing process, thereby producing building materials that are environmentally friendly and have excellent compressive strength. First of all, by recycling the waste abrasive sludge of CRT CRT panels containing heavy metals, we can not only solve environmental pollution problems and save resources, but also develop a method of manufacturing eco-friendly building materials that can significantly reduce carbon dioxide emissions at the process stage. to provide.

Description

Preparation method of Eco-building material using waster polishes sludge

The present invention relates to a method for manufacturing environmentally friendly building materials by recycling waste abrasive sludge generated in a cathode ray tube (CRT) cathode tube polishing and polishing process. Specifically, the present invention relates to a CRT cathode ray tube polishing and polishing process, which is one of display devices. By manufacturing waste building material sludge mixed with briquettes and metakaolin to produce eco-friendly building material, it is possible to prevent heavy metals contained in waste polishing material from being discharged to nature. The present invention relates to a method for manufacturing an environmentally friendly building material which can be produced and can significantly reduce carbon dioxide generation compared to a building material manufacturing process using cement.

CRT (cathode ray tube) CRT panel, which is one of display devices such as TV and computer monitor, is polished and polished by using various inorganic abrasives to improve surface smoothness and maintain gloss during CRT CRT panel manufacturing process. To improve.

The polishing process consists of three stages: rough polishing, fine polishing and polishing. As the abrasive used mainly in Korea, pumice powder is used as a coarse abrasive and garnet powder is used as a fine abrasive.

In the polishing process, rouge powder, which is a mixture of iron oxide and rare earth oxide, is used. The particle size of rouge used in the CRT polishing process is fine particles of 10 mu m or less. The abrasive used in the polishing process is discharged into the sludge together with the glass scrap. Most sludge has been concentrated and dehydrated, landfilled, disposed of as cakes and used as some cement feedstock. CRT glass contains heavy metals or toxic elements such as lead, strontium and antimony (Mear et al ., 2006), these elements remain in the sludge and can act as a serious environmental pollutant if released to nature.

As a method of manufacturing a building material, in particular, a building material using cement, a manufacturing method using a geopolymer reaction is conventionally known as a method of manufacturing a building material without undergoing a firing step. Geopolymers are inorganic binders that are synthesized by the reaction of Al / Si source materials with alkalis, also called chemical cements. In particular, geopolymers are known to be excellent for fixing toxic elements such as heavy metals and nuclear wastes and for refractory materials.

In order to solve the above problems, the present invention manufactures environmentally friendly building materials using waste abrasive sludge generated in the CRT CRT panel manufacturing process, there is no firing step, it is possible to manufacture environmentally friendly and excellent compressive strength building material, what By recycling the waste abrasive sludge of CRT CRT panels containing more heavy metals, it not only solves environmental problems and saves resources, but also provides a method for manufacturing eco-friendly building materials that can significantly reduce carbon dioxide emissions in the process step. The purpose is to.

In order to achieve the above object, the present invention is to mix the waste abrasive sludge discharged in the polishing and polishing step of the CRT CRT panel manufacturing process, the coal briquettes from which unburned carbon is removed, and the metakaolin heat-treated low-grade kaolin, The present invention relates to a method for manufacturing an environmentally friendly building material prepared by adding an alkali stimulant,

(a) drying and crushing the waste abrasive sludge;

(b) adding and mixing briquettes and metakaolin to the pulverized waste abrasive of step (a);

(c) mixing the alkaline stimulant to the mixture of step (b) to produce a molding composition;

(d) supplying the mixture of step (c) to the mold and pressing after curing;

It provides a method for producing an eco-friendly eco brick using waste abrasive sludge discharged after the CRT CRT panel polishing process comprising.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention is to improve the polishing and gloss by using various inorganic abrasives in order to improve the smoothness of the surface and maintain the gloss of the CRT CRT panel production process, at this time, eco-friendly construction using waste abrasive sludge discharged after the polishing and polishing process It provides a method of manufacturing eco-friendly eco brick as a material.

In detail, in the CRT CRT panel production process, the abrasive used in the polishing process and the waste abrasive sludge mixed in the glass scrap detached from the CRT after the polishing process are concentrated and dewatered and discharged into the cake state (about 30% by weight of moisture). And drying it, pulverizing it into a powder, and mixing the pulverized powder and the metakaolin produced by heating unburned carbon and briquette of low kaolin at a high temperature through a flotation process. By further mixing and compression molding to produce a geopolymer molded body and curing it, it does not naturally discharge various toxic substances contained in the waste abrasive sludge, or heavy metals such as lead, strontium, antimony, to prevent environmental pollution, waste resources Eco-friendly bricks with economic and environmental effects and excellent compressive strength There can be referenced. 1 is a flow chart of a method for producing an eco-friendly eco brick using waste abrasive sludge discharged from the CRT CRT panel production process of the present invention.

The waste abrasive sludges of the present invention include roux as a rough abrasive, pumice as a fine abrasive, garnet as a fine abrasive, and iron oxide or rare earth oxide as a polish. Pumice and garnet can be recovered and reused as abrasives by dry particle size separation of dry abrasive sludge. However, it is difficult to recover fine particles of rouge as fine particles and contain glass scrap. However, the silica component is 50.5% and the alumina component is 10.1%. When aluminum is replenished from briquette materials and metakaolin, it is effective to improve the compressive strength in manufacturing the eco-friendly eco brick of the present invention.

In the present invention, the eco-friendly eco-brick manufacturing method, step (a) is dried and crushed waste abrasive sludge (water content of about 30% by weight) discharged from the CRT CRT panel production process. As a method for drying and crushing the waste abrasive sludge may be used a method known in the Republic of Korea Patent Registration No. 10-0534151 (applicant geological resources research institute).

Specifically, the storage process for storing the sludge in the cake state in a storage tank; An input process of adjusting the thickness of the sludge stored in the storage tank and inputting it to the rotary kiln; A first crushing process of charging crushing medium into the rotary kiln to impart sludge to crush the sludge to improve the drying efficiency of the sludge; It is characterized by consisting of; a second crushing process for passing the crushed sludge particles through a pin mill (secondary crushing). In the disintegration process, coarse particles may be separated by classifying using an air classifier, and only fine particles may be obtained.

The present invention is characterized in that the waste abrasive particles crushed through the step (a) are formed of very fine particles having a size of 0.1 μm to 15 μm.

In the present invention, the eco-friendly eco-brick manufacturing method, step (b) is a step of mixing by adding the briquettes and metakaolin to the waste abrasive crushed in the step (a). The briquette material is preferably used to remove the unburned carbon by using the flotation screening method, it is more effective to use the briquette material from which the unburned carbon is removed as much as possible to improve the compressive strength of the eco-brick. In the present invention, it is more preferable to use the briquette material completely removed so that the unburned carbon becomes 0.00 wt% as the briquette material from which the unburned carbon is removed. In addition, the floating screening method may use a common floating screening method in the art. For example, the floating screening method used in Korean Patent No. 541464, Korean Patent No. 541435, Korean Patent No. 749757, etc. may be used.

In addition, the metakaolin of step (b) of the present invention can be prepared by heat-treating inexpensive low-grade kaolin at a high temperature, it is known that it can form metakaolin by heat treatment at about 700 ℃.

The mixing ratio of the waste abrasive pulverized in the step (b) of the present invention and the briquettes and metakaolin added thereto is 50 to 150 parts by weight of the briquettes and the metakaolin 50 based on 100 parts by weight of the waste abrasive pulverized in the step (a). A mixture of ˜150 parts by weight, preferably 75-120 parts by weight of briquettes and 75-120 parts by weight of metakaolin is suitable for improving the compressive strength of the eco brick. It may occur or be vulnerable to shock.

The present invention provides a method for producing an eco-friendly eco brick, wherein step (c) is performed by adding an alkali stimulant to the mixture of the pulverized waste abrasive, briquette and metakaolin mixed in step (b). Thus, the geopolymer molded body can be formed. It is preferable to use an aqueous sodium hydroxide solution as the alkali stimulant.

The aqueous sodium hydroxide solution of the present invention is preferably added in an amount of 40 to 200 parts by weight, and most preferably in an amount of 75 to 150 parts by weight based on 100 parts by weight of the crushed waste abrasive. When the sodium hydroxide aqueous solution is added in an amount less than 20 parts by weight with respect to the flooring material, the affinity between the particles is low, and it is difficult to press-form and form a geopolymer. In addition, when the sodium hydroxide aqueous solution is added in excess of 50 parts by weight with respect to the flooring material, the state of the mixture becomes a slurry or gel state, which is inappropriate for press molding.

The aqueous sodium hydroxide solution of the present invention provides an excellent compressive strength in the production of eco-brick by the geopolymer reaction of sodium hydroxide solution dissolved in ultrapure water at a concentration of 5 to 30 mole / L, preferably 6 to 12 mole / L It is appropriate to. When the concentration of the aqueous solution of sodium hydroxide is less than 5 mole / L, there is a problem that the compressive strength of the eco-brick decreases, and does not increase to the target compressive strength even if the curing time is increased. When the concentration of aqueous solution of sodium hydroxide exceeds 30 mole / L, it shows a relatively high compressive strength during curing. However, as the curing time increases, the compressive strength tends to decrease. Increasing the cost of the raw material increases, and a large amount of sodium hydroxide remains in the eco-brick, there is a problem that can cause corrosion of metallic building materials such as rebar after construction.

The present invention is not particularly limited to the process of mixing the pulverized waste abrasive, briquettes, metakaolin and alkaline stimulant, mixed in a mixer for 3 to 5 minutes at a rotation speed of 30 to 100 rpm, preferably 60 rpm It is desirable to.

In the present invention (d) step, by supplying the molding composition of the step (c) in the molding die and press molding, it is possible to manufacture the eco-brick by curing. The molding die may use various molding dies according to the shape, shape, thickness or size of the eco brick to be manufactured. The pressurization conditions of the press molding are preferably pressurized for about 1 to 5 minutes at 5 to 15 kgf / cm 2.

The present invention can manufacture the final eco-brick by curing the molded body after the press molding in the step (d). Curing process is the final hardening process of concrete or eco-brick, which is the most important step to reach final compressive strength.

Curing conditions of the present invention is preferably cured for at least 1 day to 28 days at a temperature of room temperature to 80 ℃, preferably room temperature to 60 ℃. If the curing temperature is less than room temperature, the compressive strength is low, the problem of slow curing occurs, if the curing temperature exceeds 80 ℃, the geopolymer is rearranged particles are formed to form a zeolite (zeolite) rather compressive strength It tends to decrease.

After finishing the curing process of the present invention, the eco-brick can produce an eco-brick having a final compressive strength of 10 to 42 Mpa.

As can be seen in Table 2 and Table 3, the present invention does not necessarily increase the final compressive strength of the eco brick as the amount of the sodium hydroxide solution is added, the concentration of the sodium hydroxide solution is increased, or the curing time is increased. According to the method of manufacturing eco-friendly eco brick using the geopolymer reaction of the flooring of the present invention, the final compressive strength of the eco brick can be adjusted by appropriately adjusting the concentration, amount of addition, curing temperature and curing time of the aqueous sodium hydroxide solution. Eco-friendly eco-brick with excellent compressive strength can be produced by curing only without the firing step. Therefore, the green sulfur eco-brick manufactured by the manufacturing method of the present invention is expected to have a high expected effect when used for construction due to the fast coagulation effect and high strength characteristics compared to Portland cement.

The present invention is a method for producing an eco-friendly eco-brick using geopolymer reaction by mixing the waste abrasive generated in the CRT CRT panel production process with a briquette, metakaolin and alkaline stimulant, the hydroxide and the briquette and the metakaolin and alkaline stimulant By producing eco-friendly eco-brick using sodium aqueous solution, it has the advantage of recycling the floor materials of thermal power plants that are discarded as waste, and can reduce the environmental pollution by reducing the generation of carbon dioxide, and improve the compressive strength only by curing without separate firing process. It can be effective.

1 is a schematic view showing a method for manufacturing an eco-friendly eco brick using the CRT CRT panel process waste polishing of the present invention,
2 is a graph showing the correlation between curing time and compressive strength for each alkaline stimulant concentration according to Example 1,
3 is a graph showing a correlation between curing time and compressive strength for each alkaline stimulant concentration according to Example 2.

Hereinafter, the present invention will be described in more detail based on the following examples. However, the following examples are not intended to limit the invention only.

[Example]

After the surface polishing process of the CRT CRT, the cake-like sludge (containing about 30 wt% of water) collected in the wastewater treatment plant was thoroughly dried in an oven at 105 ° C. for at least 24 hours.

The dried sample was hardened by the coagulation of fine particles with evaporation of water, and was then pulverized with a pin mill for single separation of abrasives. In order to supplement the Al source required for the geopolymer reaction, the amount of briquettes from which unburned carbon was removed by flotation was mixed with metakaolin heated at 700 ° C. in domestic low-grade kaolin.

Sodium hydroxide was dissolved in distilled water to prepare a NaOH solution of 6M, 8M, 10M, 12M. The coal briquette, metakaolin, and waste glass abrasives, which are unburned by removing the unburned carbon, are mixed in the ratio shown in Table 1, and the prepared NaOH solution is added to Liquid / Solid based on the weight ratio (where liquid is an aqueous sodium hydroxide solution and solid is Waste abrasive, briquette, and metakaolin mixture.) Was mixed so that the ratio was 0.375: 1.0, and mixed in a mixing apparatus for 5 minutes. The mixed samples were collected 15g per specimen and put into a mold of Φ15mm to press a force of about 100kgf / ㎠ to prepare a geopolymer molded article for compressive strength measurement. The molded product was cured in an oven at 60 ° C. to measure the compressive strength. In addition, changes in compressive strength were compared by varying curing time for 1, 3, 7, 14, and 28 days. Table 1 shows the mixing ratio, curing temperature and time conditions of briquette, metakaolin and abrasive sludge.

[Table 1] Conditions for the production of non-fired eco bricks (cure temperature 60 ℃)

※ Abrasive Abrasives: Disintegrated Abrasive Abrasives, Briquettes: Briquettes with unburned carbon removed, Metakaolin: Metakaolin prepared by heating low-grade kaolin at 700 ° C, Liquid: Sodium hydroxide aqueous solution, Solid: Abrasive abrasives, Briquettes and meta Mixture of kaolin.

Particles that cannot be recycled as abrasives in the waste abrasive sludge are a mixture of amorphous materials including glass particles polished to 15 µm or less classified by an air classifier, rare earth minerals, vasnesite, and Ce oxide. In chemical composition, 50.49% of SiO ₂ , 10.10% of Al ₂ O ₃ , 9.55% of Fe ₂ O ₃ , and Ca, K, Na, Ti, Mn, P and other heavy metals such as Sr, Pb, Zn, Ni, and the like are contained.

For the powder mixed with the waste abrasive sludge, briquettes and metakaolin, it was found that the most moldability was added by adding 37.5% by weight of NaOH solution.

The powder mixed with waste abrasive sludge 30%, ash 35%, and metakaolin 35% is represented as 'ABM-300', and the powder with mixed waste abrasive sludge 40%, ash 30% and metakaolin 30% is 'ABM-400' It is shown. In order to find the appropriate alkali concentration for the ABM powder and alkali activity reaction, the concentration of NaOH solution was gradually increased from 6M to 12M. And cured at 60 ℃ 1, 3, 7, 14, 28 days intervals, and measured the compressive strength of the formed eco-brick, the results are shown in Table 2 (ABM-300) and Table 3 (ABM-400), Figure 2 (ABM-300) and FIG. 3 (ABM-400).

2 and Table 2 show the results of curing the molded products prepared by mixing ABM-300 powder and NaOH at 60 ℃ curing strength. The compressive strength at 1 day cured at 6M was 13.8Mpa and slightly increased to 14.7Mpa at 28 days, which explains the initial strength expression, which is a characteristic of geopolymer. In comparison with the concentration of NaOH solution, the strength was increased as the concentration increased from 6M to 12M, and increased to 41.5Mpa when cured for 28 days at 29.9Mpa for 1 day curing at 12M concentration.

[Table 2] Curing at 60 ℃ (ABM-300)

3 and Table 3 show the compressive strength results of the molded product prepared by mixing ABM-400 powder and NaOH solution. As a result, as shown in FIG. 2, as the curing days increased from 1 day to 28 days, the compressive strength was increased finely. In addition, the higher the concentration of NaOH, the greater the strength and 12M 1 day curing was found to be 36.5Mpa after 28 days curing at 30.1Mpa. However, ABM-400 showed slightly lower strength than ABM-300. However, both powders showed more than 20Mpa in all conditions except 6M compared to KS L 5201 Portland cement specification. Portland Cement Normal (Class 1) has 7-day strength of 20Mpa or more and 28-day strength of 29Mpa or more.

[Table 3] Curing at 60 ℃ (ABM-400)

Claims (8)

In the manufacturing method of eco-friendly eco brick using waste abrasive sludge discharged after CRT CRT panel polishing process,
(a) drying and crushing the waste abrasive sludge;
(b) adding and mixing briquettes and metakaolin to the pulverized waste abrasive of step (a);
(c) mixing the alkaline stimulant to the mixture of step (b) to produce a molding composition;
(d) supplying the mixture of step (c) to the mold and pressing after curing;
Eco-friendly eco brick manufacturing method using the waste abrasive sludge discharged after the CRT CRT panel polishing process comprising.
The method of claim 1,
The molding composition of step (c) is an eco-friendly eco-brick manufacturing method of mixing 50 ~ 150 parts by weight of briquette material, 50 ~ 150 parts by weight of metakaolin and 40 ~ 200 parts by weight of alkaline stimulant based on 100 parts by weight of the pulverized waste abrasive.
The method of claim 2,
The alkaline stimulant of step (c) is a method for producing an eco-friendly eco-brick is an aqueous sodium hydroxide solution.
The method of claim 3,
The aqueous sodium hydroxide solution is 6 to 12 mole / L environmentally friendly eco-brick manufacturing method.
The method of claim 1,
Curing the step (d) is a method for producing an eco-friendly eco-brick curing at room temperature to 80 ℃.
The method of claim 5,
The curing is a method for producing an eco-friendly eco-brick curing in 1 to 28 days.
The method of claim 1,
The briquette material of step (b) is a method of producing eco-friendly eco-brick is a briquette material is unburned carbon is removed by flotation.
The method of claim 1,
Disintegrated waste abrasive of step (a) is a method for producing an eco-friendly eco brick having a particle size of 0.1 to 15 ㎛.

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