KR101110265B1 - Method for manufacturing multi-cellular body with low expansion and high strenght by using waste liquid crystal display glass and multi-cellular body made by the method - Google Patents

Abstract

A method of recycling the waste LCD glass is presented. A method for producing a low thermal expansion and high strength inorganic foam from a solid residue on glass while extracting valuable indium and tin components from waste LCD glass, and an inorganic foam having low thermal expansion and high strength produced by the method are disclosed.

Waste liquid crystal display glass, LCD monitor, valuables recovery, recycling, foam, water treatment media.

Description

METHOD FOR MANUFACTURING MULTI-CELLULAR BODY WITH LOW EXPANSION AND HIGH STRENGHT BY USING WASTE LIQUID CRYSTAL DISPLAY GLASS AND MULTI-CELLULAR BODY MADE BY THE METHOD}

The present invention disposes after using other electronic products related to LCD, such as TV, LCD monitor, notebook computer, mobile phone, etc., equipped with waste LCD glass or LCD monitor generated during the manufacturing and processing of LCD glass (LIQUID CRYSTAL DISPLAY GLASS). Method for producing low thermal expansion high strength foam which can be used for various purposes from extracting indium and tin, which are valuables, from waste LCD glass produced in electronic products It relates to a low thermal expansion high strength foam produced by the method. The present invention contributes to the environmentally friendly waste disposal and efficient use of resources.

The rapid development of image media technology is rapidly replacing display monitors with LCDs from existing CRTs. As a result, the amount of waste glass for LCD panels, which is related wastes, is increasing and the speed of occurrence is getting faster. In Korea, a country with strong display technology, the dissemination of LCD-related products is very early, but the generation of waste products is very small. However, as the production of LCD panel-related products increases, the production process line of LCD glass itself or LCD panel production The amount of waste LCD glass generated from the process line has already reached over 35,000 tons per year. In addition, the cycle of disposal, which becomes inefficient after supplying LCD-related products, will also occur within the next few years, so the generation of waste LCD glass is expected to increase more rapidly. This waste LCD glass must be recycled and treated in an environmentally friendly manner.

Currently, research and methods for extracting and recovering liquid crystals, indium, or tin, which are valuable substances present in the waste LCD glass, have been proposed for the waste LCD glass, but LCD glass, which is the waste after extracting the valuable substances, has been proposed. The residue or waste LCD glass itself lacks special recycling technology in consideration of economic feasibility, and the entire amount generated is incinerated or landfilled.

Incineration and landfill treatment of waste LCD glass makes it difficult to comply with EU's WEEE regulations of 75% recycling rate and 65% EPR recycling rate. This is because the relative weight of is high. For this reason, in order to reinforce the international competitiveness of producers and countries, it is very important to prepare an effective recycling plan related to waste LCD glass. Thus, recycling methods of waste LCD glass have been proposed in various forms.

In 1993, VICOR, Germany, used EDV, Elctronikschrott, Abfallwirtschaft 1993, pp. A recycling method for recovering liquid crystal from waste LCD glass has been proposed in 231-241, but there is no mention of the use of waste LCD glass itself. However, this method of recovering the liquid crystal is not practical because it is not only dioxin is generated in the liquid crystal recovery process but also very economical.

In 2000, Sharp manufactured a process for recovering materials such as organic matter, spectroscopic plate, and color filter present in LCD panel at a temperature range of 450 ^° C. to 650 ^° C. in the state of blocking the air in Japanese Patent Laid-Open No. 2000-24613. Has been proposed, but it is not about LCD glass. In 2001, Sharp produced three patent applications (Japanese Patent Laid-Open No. 2001-305501, Japanese Patent Laid-Open 2001-305502, Japanese Patent Laid-Open 2001-337305) to recover liquid crystals from waste LCD panels, shred LCD glass, and then attach them to glass substrates. The technique of finally recovering glass after removing a thin film is disclosed. It is proposed here that the recovery of the effective metal is possible if necessary, but it suggests only a method for use as a gallet glass which is used by partially adding the remaining glass to the manufacture of LCD glass. According to these proposals, the recovered glass surface is contaminated and the glass is made of STN LCD glass (Super Twisted Nematic LCD) with melting temperature of 1000 ^o C and borosilicate glass composition TFT LCD with melting temperature of 1300 ^o C. Film Transistor LCD) is recovered and classified as a very big disadvantage in the process.

In 2002, Densho of Japan, in Japanese Laid-Open Patent Publication No. 2002-346505, primarily removes gaseous wastes generated by heating carbon glass near the melting temperature of LCD glass by activated carbon adsorption and supercritical water treatment. Wastes are removed using a separate physical treatment technology, leaving only the glass part, sandblasting the remaining glass to remove deposits, washing and grinding, and finally recovering the LCD glass substrate to manufacture new LCD glass. It proposes a method for reusing waste LCD glass that is partially added. However, the composition of the LCD panel is divided into organic materials such as liquid crystal and inorganic glass, which is the recovery of liquid crystal or the recovery of waste LCD glass by physicochemical treatment of raw materials for manufacturing new LCD glass or new LCD panel. Supplemental use is considered to be economical.

2004 Merck (Roland Martin, Brigitte Simon-Hettich, Werner Beckedr, Proc. Int. Disp. Workshops, vol. 11, 583 (2004), proposed a method of lining agent that prevents corrosion of incinerator walls and coal substitute material used as silica or foundry sand substitute or reducing agent for metallurgical process.

In 2005, Sharp, Japan, reported in Sharp Gibo No. 92, p 17 (August 2005), how to make tiles with waste LCD and recover indium.

JEITA was proposed by Merck in 2004 from the LCD Industries Research Committee, Japan Electronics and Information Technology Industries Association: Recycling of LCD Panel, http://home.jeita.or.jp/device/lirec/english/enviro/recycle.htm In a similar way, it has proposed the use of silica as an alternative material for the zinc refinery.

In 2007, Roland Martin of Germany, in an extension of Merck's research in 2004, used waste LCD glass as a partial additive or substitute for melting, metallurgy and incineration processes in the 900 ^° C to 1700 ^° C temperature range. A technique for using has been filed (US Patent Application Publication US 2007/0193414 A1).

In Korea, Y & B Materials Tech Co., Ltd. in Korea Patent Application No. 10-2004-00767 06 (2004) to remove the impurities by crushing, sieving, magnetic screening, washing, drying process to ensure the appropriate particle size Although it has been proposed a method for reusing glass, as mentioned above, there have been no reports of practical methods or processes domestically and internationally.

Although wastes from glassy systems such as waste LCD glass are highly recyclable due to their physical and chemical properties, effective recycling is not achieved because the raw materials for glass production are cheap. It is because it is very difficult to create high value added by recycling because of high pretreatment cost for recycling. Under these conditions, one way to create an effective and possible high value by recycling waste LCD glass is to manufacture foam glass using waste glass, and more specifically, to increase the value of inorganic foam having high thermal value and low thermal expansion strength. Manufacturing.

Foamed glass is a foam formed of a composite of glassy solid and gaseous phase. When soda-lime glass is used as a main component, it is mainly used as a high-grade building insulation material. In the case of a foam whose main component is borosilicate glass, it has a low coefficient of thermal expansion. It can be used as a thermal insulation insulator for chemical process such as tank insulation, which has higher added value than building insulation.

Therefore, if recycling waste glass or low thermal expansion high strength foam is used as raw material for waste LCD glass, the process can be recycled, and indium and extraction, which are valuable residues in waste LCD glass, can be recycled. I think this will be.

As a recycling method similar to the present application, SAG in Germany mixed the LCD glass powder pulverized to a size of 40 or less with a glass plate of soda-lime glass in 1997. ^{o It} proposed a method to make foamed glass beads of 5mm to 15mm diameter at a temperature of C to 850 ^o C and use them as lightweight aggregate, building insulation, and the like. In this proposal, the low melting point soda-lime glass is mixed with glass or the foam is spherical with a size of 15mm or less. Because of the high softening point of LCD glass, it is difficult to foam by LCD glass itself. It is intended to be lowered. However, it is possible to lower the softening point or melting point of the LCD glass for foaming by incorporating a large amount of low melting soda lime glass, but since the borosilicate glass of TFT LCD glass itself is not foamed, the borosilicate glass of a single composition is foamed. Jinnin foams with low thermal expansion properties that can be obtained cannot be produced. In addition, since the foam is manufactured with a diameter of 15 mm or less, the basic composition of LCD glass is borosilicate glass, which has a low coefficient of thermal expansion and a rheological characteristic that is different from that of soda lime glass. It is difficult, but since the heat treatment conditions are difficult after foaming, it is almost impossible to produce a normal product such as severely lowering the mechanical strength of the foam due to the occurrence of numerous cracks in the foam.

This study is a substantial basis for demonstrating that the process of producing foam using waste LCD glass as a raw material and that the process is very different from the existing manufacturing method using soda lime glass. Currently used glass for TFT LCD is borosilicate glass containing a large amount of aluminum, melting point of 1300 ^o C to 1400 ^o C, so its melting point is very high compared to soda lime having a melting point of about 800 ^o C. This high melting point difference will be the biggest obstacle to the use of waste LCD glass as a raw material for foam glass. However, the cause of the high melting point is caused by the difference in the composition of the glass, the difference in the component may cause a fatal obstacle in the manufacturing process, but from a different point of view, unlike conventional foam glass manufactured with soda lime Otherwise, physical and mechanical properties such as high hardness, compressive strength, bending strength, high abrasion resistance, and especially low thermal expansion properties can be enhanced, thus exceeding the use of foams made of conventional soda-lime glass, which was limited by low physical and chemical properties. It may be a low thermal expansion high performance foam glass or inorganic foam.

Therefore, this application seeks to find a recycling method for waste LCD monitor glass as an urgent task in Korea, the world's number one display powerhouse, and as a solution, it provides high functionality to waste LCD glass and has low heat that can be used for various applications. In order to manufacture an expandable high-strength inorganic foam, as part of the process, it is proposed a process that can extract and recover indium or tin as a valuable component in the waste LCD glass.

In addition, the present application proposes a method for producing a spherical form, a bulk form, and a bulk form of the inorganic foam combined with the spherical form as an inorganic foam.

The inorganic foam manufactured as described above can be used as a lightweight, porous thermal insulation material, and due to its mechanical properties such as high hardness and abrasion resistance, lightweight aggregates, friction agents, abrasives, microorganism media in water treatment facilities, bricks for ecological rivers, and hard stones It can be used for many purposes such as planting materials, alternative hydroballs, etc. In particular, it is a low-expansion inorganic foam having a low coefficient of thermal expansion, and thus, as a lining agent for lining materials for chemical processes, such as thermal insulation for LNG storage tanks, and stacks. It can have a wide variety of uses.

Existing commercially available foam glass manufacturing processes, such as those performed by Pittsburgh Corning, consist of a raw glass manufacturing process with a soda-lime composition for producing foamed glass and a foam firing process for producing foamed glass with the raw glass. A key technology and the biggest drawback of the existing foam glass manufacturing process is the manufacturing of soda lime raw glass to be foamed first. For the production of soda-lime raw material glass, more than one-half of the total facility investment costs and energy costs for melting are required. Therefore, numerous studies have been proposed, including a patent on a method for manufacturing foam glass using the existing waste glass as it is without making a raw material glass for foam glass production.

Accordingly, the first solution of the present application for producing foam using waste LCD glass does not require melting facility or energy for melting waste LCD glass, and then directly pulverizes the waste LCD glass and then selects an appropriate foaming agent. It is intended to find a way to produce a foamed glass by the foaming step by adding and mixing.

In the conventional commercialized foam glass manufacturing process, the basic reason for separately manufacturing raw glass for foam glass production without using waste soda lime glass and using a lot of energy is that the constituents of the glass with the carbon foaming agent are preferably used at low temperatures. By reacting, the foaming is predominantly made, and the foam produced is obtained in a foam of as large size as possible with uniform pores.

However, a method for producing foamed glass using waste glass is to make foaming predominantly by chemical reaction of the appropriate blowing agent itself. That is, in this case, the foaming mechanism is melted in a state in which fine waste glass particles are surrounded by a blowing agent, thereby becoming a softened state of high viscosity, and at the same time, the blowing agent surrounded by the softened glass undergoes a decomposition reaction to generate gas, causing swelling. The state which stabilized the state is foamed glass.

Therefore, there are many variables such as the characteristics of the blowing agent in order to make economical high quality foam glass using waste glass, but first of all, the softening point of the waste glass should be low. In 1997, SAG of Germany mixed a large amount of flat glass, soda-lime glass, for the foaming of LCD glass. TFT LCD glass has a softening point of more than 1300 ^o C. Softening point of raw waste LCD glass for foaming To lower.

In addition, the foam is made of foam beads with a diameter of 5mm to 15mm, the basic chemical composition of the LCD glass borosilicate glass is not only low thermal expansion coefficient, but also the foaming itself when the foam size increases because the rheological properties are different from soda lime glass It is difficult, but since the heat treatment conditions are difficult after foaming, it is almost impossible to produce large-size bulk foam products such as severely lowering the mechanical strength of the foam due to the occurrence of numerous cracks in the foam.

The second problem to be solved in the present application by targeting the lung LCD glass, other low-melting glass or Only pure waste LCD glass without incorporating the alkali that can be expected the effect of the melting point of softening point of the LCD glass 1300 ^o It is intended to manufacture low thermal expansion high performance foam glass or inorganic foam at foam firing temperature as low as possible, and to develop a method for foaming the foam regardless of its shape and size, whether spherical or bulky. will be. In addition, in connection with the process of the present invention will be examined together with the way to extract and recover valuable components such as indium and tin present in the waste LCD glass.

According to the present invention, indium and tin components, which are valuables, are extracted from the waste LCD glass, and low-expansion and high-strength inorganic foams are prepared as solid residues on the glass.

This manufacturing method targets waste LCD glass produced during the manufacturing and processing of LCD panels and waste LCD glass generated during the disposal process after the use of electronic products related to the LCD panel. A hydration reaction process of waste LCD glass (step 1-1) to hydrate to have a water content of 0.67% or more and to extract indium and tin components contained in the waste LCD glass to the hydration solution during the hydration process;

The indium and tin components are extracted with the progress of the hydration reaction in the step 1-1, and the hydration solution containing these components is separated and washed with wet-pulverized and hydrated waste LCD glass powder having a particle size of 50 μm or less. Separation process (step 1-2);

On the basis of 100 parts by weight of the waste LCD glass powder hydrated as a foaming aid to the hydrated waste LCD glass powder wet-pulverized with a particle size of 50 μm or less with the progress of the hydration reaction by the steps 1-1 and 1-2, Foaming aid composition for adding at least one of 0.1 to 3.5 parts by weight of a high temperature active carbon material (eg, crystalline graphite), 0.1 to 10.0 parts by weight of sulfate, and 0.1 to 10.0 parts by weight of carbonate An addition step (2 steps);

Kaolin, PVA, which has the functions of a sintering aid and a molding binder in order to maximize the sintering effect during firing without adding an alkaline component such as a flux for firing and foaming at low temperature to the raw powder mixture obtained by the above 2 steps A granulation step (3 steps) of adding starch, basalt, and the like water together to granulate to a size of 0.5 mm to less than 3.0 mm in diameter under pressure;

A press molding step (step 4-1) of making the granulated raw material powder mixture obtained by the above step ³ into a spherical shaped body having an average diameter of less than 3.0 mm to 30 mm and a density of 1.2 g / cm ³ to 3.0 g / cm ³ ;

Alternatively, in order to obtain a bulky inorganic foam from the granulated raw powder mixture obtained by the above 3 steps, the compacted body is formed by pressure molding to a density of 1.2 g / cm ³ to 3.0 g / cm ³ to form a bulk shaped body. A pressurized charging step (4-2) to pressurize the raw material powder mixture, which is contained in or granulated, into a die, and compacted so that the density of the raw material powder mixture is 1.2 g / cm ³ to 3.0 g / cm ³ ;

Injecting the spherical shaped body obtained in step 4-1 into a rotary kiln adjusted to 450 ^° C. to less than 750 ^° C. to dry and preheat (step 5-1);

Or a step of introducing into a tunnel kiln controlled to 450 ^o C to less than 750 ^o C in order to dry and preheat the granulated raw powder mixture, which is contained in the compacted compact or die formed in step 4-2 and pressurized. Step 5-2);

Foam firing step (6-1 step) of firing by introducing into a rotary kiln adjusted to a temperature of 850 ^° C to 1100 ^° C in order to foam firing the spherical molded body after the preheating step 5-1;

Or in order to foam-fire the granulated raw powder mixture, which is immersed in a compacted compact or a die that is subjected to the preheating process of step 5-2, and compacted by pressing, the temperature of the tunnel kiln adjusted to a temperature of 850 ^o C to less than 1100 ^o C A foam firing step (6-2 step) which is introduced into the foam firing part and fired into a bulk inorganic foam;

A stabilization step (step 7) of stabilizing the foamed foam at 500 to 650 ° C. through the foam firing step 6-1 or 6-2;

Annealing and surface modification up to 20 to 40 ° C. to maintain the mechanical properties of the spherical inorganic foam and the surface porosity after stabilization of the seven steps (step 8-1);

Or annealing heat treatment at 8 to 40 ° C. for maintaining the mechanical properties of the bulky inorganic foams which have undergone the stabilization in step 7 (step 8-2);

It is a method of producing a low thermal expansion high strength inorganic foam comprising a.

In the method of manufacturing low thermal expansion high strength inorganic foam as described above, in the case of spherical foam, the adhesion or foam between the foamed foam and the foam in the foam firing step of the molded product of the raw powder mixture after step 4-1 and before step 6-1 is rotated. Magnesia powder, alumina powder, smelting furnace slack powder, etc., as an anti-adhesive agent, can be applied to the surface of the molded body before foaming or introduced into the rotary kiln of the molded body as an anti-adhesive agent in order to prevent adhesion to the tall wall. have. In addition, in the case of the bulk foam, the above-mentioned foamed bulk foam after the foaming firing step of 6-2 can be easily separated from the formwork, and the magnesia powder, alumina powder, smelting furnace slag powder of metal smelting, etc. A separate preparation process may be added to mix 1.5 to 3.0 parts by weight with respect to 1 part by weight of carbonaceous material, add water to make it like porridge, and then apply it to the inner wall of the formwork containing the raw material mixture and dry it.

In order to manufacture the spherical foam, the furnace in which the above 4-1 and 5-1 processes are performed, the temperature of the preheating part and the furnace inside which the temperature of the inlet is controlled to be less than 450 ^o C to 750 ^o C is 850 ^o C. It is preferable that the rotary kiln consisting of a foam firing portion adjusted to less than 1100 ^° C or a continuous process furnace that connects two rotary kilns capable of continuously preheating for drying and preheating and heating for plastic foaming. In order to make the foam in the present invention, there must be a process for drying and preheating, followed by a foam firing process, followed by a stabilization and slow cooling heat treatment process. In the actual process, a rotary kiln for each process or a corresponding furnace, In other words, if there are three rotary kilns, a continuous process takes place. However, in consideration of the cost of the facility, if the whole process is to be performed in one rotary kiln, a furnace designed to have different drying, preheating, and foaming in one rotary kiln may be used. The foams have thermal conductivity as a simple inorganic raw material before foaming, but after foaming, foams are changed to physical properties having relatively very low thermal conductivity that can be used as insulation and insulation due to the generated waste pores. It is short, but long time slow heat treatment is required. Therefore, a separate rotary kiln or such slow cooling heat treatment device for slow cooling heat treatment process is required.

And in the final slow cooling process, the manufactured spherical foam having a size of less than 5mm to 35mm is characterized in that the surface polishing apparatus is installed in the slow cooling furnace so that the porosity of the foam appears on the surface in order to increase the efficiency of the expected use. do.

On the other hand, in the case of the bulk foam, the size of the molded body is not so large as that of the spherical foam, and the raw material mixture powder is pressed in the form of granules, so it is impossible to use the rotary kiln. You should use the same type of furnace as Therefore, a single tunnel kiln must consist of a preheating section of 450 ^o C to 750 ^o C and a foamed plastic section of 850 ^o C to 1100 ^o C. And since the size of the foam after foaming is also incomparably larger than that of spherical foams, the time required for slow cooling heat treatment increases exponentially with increasing foam size. In the case of the present invention, even if the size of the foam is 600 x 600 x 150mm, a slow cooling time of 12 hours or more is required, and a separate slow cooling heat treatment furnace or facility is required. Therefore, in order to stabilize the foam immediately after plastic foaming, it is efficient to remove it from the form immediately after stabilizing at 500 to 650 ° C. and to introduce it into the next slow cooling process.

As a result of the practical use of the present invention, the national social effect is to meet the recycling requirements for the exported electronic products by establishing the recycling method of waste LCD glass generated in the electronic industry, thereby meeting the domestic waste resource recycling policy and contributing to the improvement of international competitiveness. Will be done.

In the present invention, the foam to be manufactured by using the waste LCD has a thermal insulation function, which is a function that the inorganic foam having a waste hole is expressed like a foam that can be manufactured with soda-lime glass, so it can be used as an excellent thermal insulation material for lightweight structures or buildings. Can be. In addition, since the LCD glass basically has a structure of borosilicate glass, the inorganic foam produced is also low thermally expandable and has high strength, so that it can be used as a thermal insulation material for chemical processes that cannot be realized by soda lime foamed glass.

The final molded contours of the inorganic foams of the invention with low thermal expansion and high strength can be produced in blocks, spheres or in combination of spheres depending on the application and the size of each can be arbitrarily adjusted.

The bulk foam can be used as a heat insulating material for various purposes and as a light weight thermal insulation material for general construction as it is soda lime glass foam, and the spherical inorganic foam is light and durable with high functionality by making pores appear on the surface through surface polishing. It is expected to be used as a media for water treatment (Moving Bed Bio Reactor, etc.) as a recycled BIO media, and it can be used for foodstuffs (eg turbulence, hydro balls), jeans washing balls, and abrasives. In addition, they are mixed with cement rather than used alone to fill cement bricks, ecological river blocks or cement structures, thereby lowering the thermal conductivity of cement bricks and structures, thereby providing insulation and thermal insulation of building and civil engineering structures. Not only can it be done, but it is also possible to reduce the weight. In addition, the present invention proceeds in conjunction with a process for effectively extracting and recovering the indium and tin components present in the waste LCD glass together with the development of the manufacturing process of the foam for waste LCD glass. It will be the way.

The technical object of the present invention is to extract and recover valuable components such as indium and tin present in the waste LCD glass in order to efficiently recycle the waste LCD panel. Is in. The reason is that the waste LCD glass basically has a composition of borosilicate glass and contains a large amount of Al ₂ O ₃ , so the softening point is much higher than that of soda-lime glass. Because you do not have. Therefore, in order to use such waste LCD glass as a raw material of the inorganic foam, it is necessary to find a foaming process technique that can be formed into various types of foam at a lower foaming firing temperature by special physical and chemical treatment of the waste LCD glass.

The manufacturing process of foam for waste LCD glass is the same process step as the manufacturing process for foam glass for soda-lime glass because the chemical composition of LCD glass is borosilicate glass but it has the basic characteristics of amorphous material called glass. Go through. In other words, the whole process of grinding the raw materials, adding and mixing the blowing agent, molding, firing and foaming, primary stabilization through quenching, and slow cooling to the final product are the same.

However, the physical properties of glass are fundamentally dependent on their chemical composition, so the physical and chemical properties such as density, hardness, melting point, coefficient of thermal expansion, crystallization temperature, etc. are all different. All progress will be different, including the conditions of the reaction. Therefore, in order to obtain an inorganic foam having a low coefficient of thermal expansion through a foaming process for waste LCD glass having a relatively low coefficient of thermal expansion and containing a high melting point component, the foam firing step and All the conditions, from the final foam morphology and mechanical properties to the heat treatment step for stabilization, must be completely different from those of the foam manufacturing process for soda-lime glass. . Therefore, the present invention is not a technology that can be easily developed by those skilled in the art, even if a conventional foaming technology for soda-lime glass is proposed.

In order to proceed with foaming of LCD glass according to the foaming principle of the glass, the waste LCD glass particles in a fine state are softened by sintering or melting in a state surrounding the foaming aid, and the particles can be bonded to each other. Should be Secondly, while the foaming aid is surrounded by fines of the waste LCD glass, it remains thermally stable without decomposition until the temperature at which the waste LCD glass powder is sintered or melted, and then the waste LCD glass powder surrounding the foaming aid is sintered. Or the molten state of the LCD glass particles in the bonded state by swelling or forming pores by generating gas through self-decomposition or chemical reaction with the constituents of the glass at the same time as the name in the state of melting and bonding with each other. .

According to the foam forming mechanism as described above, the first step for producing a foam using waste LCD glass is to maintain the state in which the waste LCD glass fine powder is sintered or melted in a state surrounding the foaming aid to be bonded to each other. Here, as a foaming aid, a material which can be usually used includes carbon materials, sulfates, carbonates and the like. LCD glass has the composition of borosilicate glass and the high temperature of Al ₂ O _{3 makes} TFT LCD glass the mainstream. Close to to allow for foaming. Therefore, when the above foaming aids are used as foaming aids for the foaming of waste LCD glass without further treatment, the LCD glass powder particles stick to each other in a state surrounding the foaming agent until softening and sintering temperatures at which foaming can proceed. It is difficult to maintain a stable state without thermal decomposition. As measures to solve these technical problems can be considered the use of a foaming auxiliary as possible can act at a high temperature do not easy to select a foaming assistant to act at a high temperature, such as that, in addition, even if it's possible melting temperature 1300 ^o In case of heating to the vicinity of C, due to the high energy cost, the economic efficiency is low and there is no possibility of practical use. For these reasons, it is difficult to find the results of the literature to obtain the foam of LCD glass using only waste LCD glass.

Therefore, one of the key points in the present invention is to use the LCD glass having a high melting point of 1300 ^o C or more as a raw material and not to reach its melting temperature, but the waste LCD glass particles stick to each other at the lowest possible temperature of less than 1100 ^o C. It is intended to attempt foaming using the sintering properties. Therefore, lowering the temperature of this sintering will be the technical focus of the present invention.

In addition, the LCD glass is borosilicate glass, which has a lower coefficient of thermal expansion than soda lime glass, making it difficult to manufacture a large-sized foam having a homogeneous porous structure. The present invention uses the technical principle of the sintering reaction, and is less than 1100 ^o C. Foaming waste LCD glass at low temperatures to produce spherical foams having a diameter of less than 3 mm to 35 mm or bulky foams that combine spherical or platy foams or spherical foams that may have dimensions of 100 x 100 x 50 mm or more. We would like to propose a solution for process technology. The principle and details are as follows.

First of all, the production of raw material glass for foaming through a hydration process of increasing the moisture content of LCD glass by the hydration reaction of waste LCD glass by moisture is started. The moisture content here indicates that the waste LCD glass contains water through a hydration reaction with water in a reactor having a grinding function, and indicates the amount of water contained in the LCD glass as a result of the hydration reaction. In other words, since% is a concept based on a total of 100, a "water content of 0.67% or more" means that the content of water contained in the glass powder is 0.67 or more based on the glass powder 100 obtained by hydration.
LCD glass is based on borosilicate glass. The silicate-based glass reacts when contacted with water as follows:

= Si-OM (alkali metal) + H 2 O = Si-OH + M + + OH - ------ (1)

This reaction is a typical hydrolysis reaction, and the formation of free hydroxyl ion with silanol groups is the beginning of the next step.

= Si-O-Si = + OH - = Si-OH + Si-O - ------- (2)

In the reaction of Eq. (2), very strong Si-O-Si bonds are broken by free hydroxyl ions, producing silanol groups and another non-crosslinked oxygen. In the following equation (3), the non-crosslinked oxygen reacts with water to generate new free hydroxyl ions, resulting in a chain reaction.

_{^{= Si-O - + H 2}} O = Si-OH + OH - ------- (3)

The water penetrated into the waste LCD glass through this reaction forms a non-crosslinking and reduces the viscosity of the glass because it is easy to change into the network structure, which affects the softening of the glass in the foam firing step Facilitates anger In addition, the moisture contained in the LCD glass is combined with a carbon foaming aid at a temperature of 900 ^° C or more to form a gaseous product (氣相 生成物) can increase the foaming efficiency. Therefore, foaming of LCD glass having a high melting point may be expected to be efficient foaming even at a temperature below the melting point. In addition, the silanol group, which is one of the OH groups formed in the LCD glass, is a free silanol group that is hydrogen-bonded to the non-crosslinked oxygen of the network but is not hydrogen-bonded, and includes a weak hydrogen bond to the cross-linked oxygen of the silicate network. The range of weak hydrogen bonds is determined by the basicity of the silicate glass, and the basicity of the glass is determined by the concentration of alkali as well as water, so that the hydration of the glass in the alkaline solution will proceed well and the foaming will be good. Therefore, the addition of a small amount of alkali may be considered to increase the efficiency of the hydration reaction. However, in the case of a foam having low thermal expandability, an alkali component remaining after the hydration reaction needs to be additionally quantitatively washed and removed.

In the present invention, the hydration reaction of the waste LCD glass is carried out in a ball mill in order to increase the stirring efficiency between the water and the glass, and the wet grinding of the LCD glass proceeds with the progress of the hydration reaction. The hydration reaction lasts more than 24 hours, during which the waste LCD glass is wet crushed to a size of less than 50 μm, leading to a water content of 0.67% or more. This moisture content is the minimum amount of water to be contained in the LCD glass for the foaming of the glass, and the higher the moisture content, the more efficiently the foaming can be performed at low temperatures. The water content can be made larger by adding a small amount of the alkaline component to the hydration solution, but in this case, the alkaline component is preferably separated, washed and removed quantitatively. This is because, if alkali remains, the coefficient of thermal expansion of the foam is increased, and the foaming and firing may cause corrosion of the device. The reason for the progress of the hydration reaction using the ball mill in this process is that a separate grinding process of the waste LCD glass is not necessary, and when the finely divided waste LCD glass and the hydration reaction solution are separated after the hydration reaction, this separation is performed. This is because the extracted filtrate can extract and dissolve the valuable indium and tin components present in the waste LCD glass, thereby increasing the efficiency of recovery of the valuable metal components as one of the recycling methods of the waste LCD glass. After separating the finely divided LCD glass, the content of indium and tin components in the filtrate was decreased by adding a small amount of inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, acetic acid, and formic acid to the hydration solution before the hydration reaction. The hydration reaction of the present invention additionally has the feature of having additional efficiency of extraction and recovery of indium and tin in the waste LCD glass.

Another technical feature for achieving foaming at the lowest possible temperature without adding a separate chemical component such as a flux that can lower the foaming firing temperature of the LCD glass having a high melting point in the present invention is low temperature sintering of the glass particles as described above Is to use the property. Bonding between inorganic particles may proceed by sintering before reaching the melting point, and bonding of particles by the sintering is effective as the distance between the particles is short. In other words, the sintering of the inorganic particles may be aggregated or bonded by diffusion of particles by lower thermal energy than when pressed or when the density of the solid phase is high. Therefore, the LCD glass is foamed in a granular or molded state having a high density rather than a powder state. Attempts to bond between glass particles will be possible at relatively low temperatures.

In the present invention, as a means for achieving this purpose, foaming aids, sintering aids and molding binders in hydrated waste LCD glass powder having a water content of 0.67% or more and an average diameter of 50 μm or less, which have been subjected to the above steps 1-1 and 1-2. Add and mix well. In this case, as the foaming aid, 0.1 to 3.5 parts by weight of carbon material having a particle size of 50 μm or less, 0.5 to 7.0 parts by weight of sulfate, and 0.5 to 10.0 parts by weight of carbonate, based on 100 parts by weight of the hydrated waste LCD glass powder. It is made of at least one of the sintering aid and molding binder also has a high viscosity material such as kaolinite, kaolin, PVA, clay, basalt powder having a particle size of 50 ㎛ or less, composed of at least one of these, The amount of addition is adjusted according to the desired density. A predetermined amount of the foaming agent, the sintering agent, and the molding binder were added to the hydrated waste LCD glass powder, and the mixture was uniformly mixed, and used as a mixed powder as a raw material composition for producing a foam. Appropriate amount of water to be slump 0) is added and pressurized to granulate to a particle having a density of average diameter of 0.5 mm to less than 3 mm and a density of 1.2 g / cm ³ or more. This assembling process and subsequent forming process together with the hydration process of the waste LCD glass is another characteristic process that enables low temperature foaming of the waste LCD glass. Thereafter, in order to obtain a foam having a desired shape from the granulated raw powder mixture, different molding processes and foam firing processes are performed.

First, in order to manufacture a spherical foam, the granulated raw powder mixture is used in a spherical molding machine so that the final molded product may have a size of less than 3 mm to 30 mm in average diameter and a density of 1.2 g / cm ³ or more and less than 3.0 g / cm ^3. Molding into a sphere while pressing. Then, the molded spherical molded product is put into a rotary kiln adjusted to 450 ^° C. to 750 ^° C. to dry and preheat. The dried and preheated shaped body is foamed and fired at a temperature of less than 850 to 1100 ° C. together with a mold release agent. The foam obtained by foam firing is stabilized at 500 to 650 ° C. and then annealed to 20 to 40 ° C. to form a spherical or cylindrical foam in a stable state.

In the case of forming a foam in the form of a block, first, the granulated raw powder mixture is put into a mold and pressurized into a block such as a plate or grid having a density of less than 1.2 g / cm ³ to 3.0 g / cm ³ . After molding, the molded body is placed in a die or the granulated raw powder mixture is directly placed in a die, and the density of the whole granulated raw powder mixture in the die is pressed to 1.2 g / cm ³ to 3.0 g / cm ³ . Lose. When the granulated raw powder mixture is packed in the form of the die, air remaining between the granulated particles is removed, and in order to remove the air more quantitatively, vibration can be further obtained. This is because if the air remains, the density of the entire raw material mixture in the formwork can be reduced to 1.2 g / cm ³ or less. Formwork containing these compacted molded articles and granulated raw material composition is introduced into a tunnel kiln composed of a drying and preheating section controlled at 450 to 750 ° C. and a foamed plastic part controlled at a temperature below 850 to 1100 ° C. Foam firing. The foam obtained by foam firing is stabilized at 500 to 650 ° C., the formwork is stripped off, and then subjected to annealing to 20 to 40 ° C. to obtain a bulk having a desired shape.

As described above, since the present invention increases the density of the molded body by pressing and molding during foaming of the waste LCD glass, the distance between the LCD glass powder particles and the particles in the molded body is much closer than that without pressing. Sintering effect is maximized during foam firing. As a result, the waste LCD glass particles are bonded to each other without reaching the melting point or softening point of the LCD glass, so that low-temperature foaming of the waste LCD glass can be achieved. When the density of the molded product obtained in the assembling process and the molding process is 1.2 g / cm ³ or less, the distance between particles of the LCD glass powder is relatively large, so that it is necessary to maintain the firing temperature until the high sintering temperature or near the melting point of the LCD glass powder. As the density of the molded body increases by more than 1.2 g / cm ^{3, the} sintering effect is increased, but when 3.0 g / cm ³ , the effect of further sintering is not large and economical due to many operations and energy problems to obtain high density. Since the spherical shaped body is relatively weak to mechanical impact, cracks are formed in the molded body during the movement of the drying and preheating processes, and are easily broken, which ultimately decreases the yield of the molded product.

Waste LCD glass has a borosilicate glass composition and high Al ₂ O ₃ content, which is not easy to be crushed due to its high hardness. However, the waste LCD glass is wet pulverized with the progress of the hydration reaction of the LCD glass proposed in the present invention. Since it is obtained as a fine powder, the grinding process of the glass for foaming is not a problem at all. However, when the hydration reaction time is short in the hydration process, not only the water content of the glass is lowered, but also because the particle size of the glass particles is large, the foaming firing temperature is increased, and the amount of addition of the foaming aid is required. However, when the particle size of the average diameter 50㎛, based on 100 parts by weight of the hydrated waste LCD glass powder, the addition amount of the carbonaceous material of the foaming aid 0.1 to 3.5 parts by weight, sulfate 0.5 to 7.0 parts by weight, carbonate 0.5 It is possible to 10.0 parts by weight, the temperature conditions of the foaming firing process is also lowered to less than 1100 ^o C and also the density of the prepared foam is lowered.

Carbon as the foaming aid can be either crystalline carbon or amorphous carbon as long as it can be decomposed at a temperature below 850 to 1100 ° C., which is capable of sintering the waste LCD glass under the above conditions. Crystalline carbon having high stability at is more preferable, and the size of the foaming aid particles is 35 to 50 µm, and it is appropriate to add 0.1 to 3.5 parts by weight based on 100 parts by weight of the hydrolyzed waste LCD glass.

If the particle size of the carbon material is larger than 50 µm, the effect of foam formation is reduced by reducing the efficiency of gas formation reaction that must be accompanied in the waste LCD glass powder, whereas the particle size of less than 35 µm before the foam firing process step is reached. This also reduces the foam formation efficiency since carbon is easily burned by the absorbed air or gas.

The present invention maximizes the sintering effect of LCD glass particles in the manufacture of foam by granulating under pressure at the time of forming the foamed LCD glass powder without adding chemical additives such as alkaline compounds to lower the foaming temperature of the waste LCD glass. Below the softening point of LCD glass, the glass particles are bonded to each other and have a characteristic of foaming. Therefore, the addition of a separate alkaline compound is not necessary to lower the foaming temperature. Of course, the softening point of LCD glass can be lowered by adding alkali glass, such as plate glass with high alkalinity like the study of SAG. However, in this case, since it is not pure LCD glass, the produced foam loses the inherent properties of borosilicate glass, which does not have the desired low thermal expansion coefficient and the mechanical strength is lowered. Addition or addition of an alkaline component such as caustic soda is not preferred.

Therefore, in the present invention, the manufacturing process of the inorganic foam using waste LCD glass as a raw material is assembled under pressure by pressing the mixed powder in which the above foaming aid, sintering aid and molding binder are added to the hydrated waste LCD glass powder. The pulverized raw material powder mixture is made of a molded body having a density of 1.2 g / cm ³ or more, and then, the dried raw powder mixture is manufactured into a foam through a dry preheating and foam firing process.

First, the spherical foam is spherically formed in a rotary kiln in which the molded body is first dried and preheated at a temperature of 450 ^° C. to 700 ^° C. Spherical foams have a size of less than 3mm to 30mm in diameter and are relatively small compared to the mass of compacts, which does not necessarily require long drying and preheating processes. It is preferable. After the drying and preheating process, the molded product is introduced into a rotary kiln, which is controlled at a temperature of 850 to 1100 ° C. together with a release agent, to prepare a foam. In order to prevent the foams from sticking together or the foams sticking to the furnace wall during the firing process, a release agent must be added together when introducing the dried molded product into the rotary kiln. The release agent should be a material that does not melt or sinter at the firing temperature, and magnesia, alumina, high melting point slag powder, and the like may be used in the present invention.

It is difficult to maintain the shape of the molded body before foaming because the foams formed during the foaming process are in a very soft state as a whole. In the case of a block, it is not a problem because the formwork contains a mixture of raw materials for foam production, but in the case of a spherical shape, a rotary kiln must be used because the rolling is required to maintain the shape. After the foaming is performed, the material itself tends to become high temperature deformation, and thus, stabilization should be performed immediately after foaming, which is performed by quenching the prepared foam to a temperature of 500 to 650 ° C. Oxidation-reduction reaction that quenches under 500 ℃ condition creates thermal stress that causes crack or fracture of foamed glass due to thermal shock and constantly regulates the pore volume of the formed foam when cooled under 650 ℃ The restraint of is limited. After the quenching process for stabilization, the foam is cooled to 40 ^o C through a separate secondary heat treatment process to remove the thermal stress from the foam firing process, thereby strengthening the mechanical properties of the foam.

Spherical foams can be used on their own, for example, as media for water treatment, and can also be incorporated into cement structures, used as lightweighting agents, or used to make shaped articles of various shapes using cement as a binder. In this case, the spherical foam is effective in utilizing its functionality because the porosity in the surface is exposed to the surface, so that a metal mesh is installed in the slow cooling furnace so that the surface of the foam can be polished. It is characterized in that a step of allowing the porous structure to be expressed.

In the manufacture of the bulk foam, the granulated raw powder mixture is compacted in a formwork of a desired size without undergoing a separate molding process such as a spherical foam, or is compacted by pressurizing the granulated raw powder mixture in a mold to obtain a desired size. Make it in the form of and put it in the formwork. In either case, the granulated raw powder mixture is pressed to a density of 1.2 g / cm ³ or more, and the formwork containing them is introduced into the tunnel kiln. In the production of the foam using the formwork, the foamed foam is formed in the form of the form under the conditions that the foaming proceeds in this process, the foam is fused to the wall of the form is difficult to separate the foam and the form after the foam firing. Therefore, the granulated raw powder mixture or granulated raw powder mixture is pressed in a mold to form a molded body into a bulk, and the mold is formed by applying a releasing agent to the inside of the die. Treatment of the release agent on the inner wall of the form is carried out in a suitable amount of water in a mixture of magnesia powder, alumina powder, smelting furnace slag powder or clay of metal smelting at a ratio of 1.5 to 3 parts by weight with respect to 1 part by weight of carbon powder such as graphite powder. By adding sludge and applying it to the inner wall of the formwork and drying it.

The bulk foams require a preheating process at a temperature of less than 450 to 750 ° C. before firing because the foam is relatively large in size compared to spherical foams. Therefore, the granulated raw powder mixture or the granulated raw powder mixture is pressed in a mold so that the dies containing the molded body formed into a bulk are passed through a drying and preheating section controlled at a temperature of 450 to 750 ° C. or lower in the turnnel kiln. And immediately after the end of the foaming is made in the foamed plastic part adjusted to 850 to 1100 ℃.

When the foam made of the foamed plastic stays in the foamed plastic part for more than a predetermined time, the foamed pores collapse, so that the foamed state must be stabilized immediately. After passing the foamed plastic part, the foam is cooled to a temperature of 500 to 650 ° C., and the porous structure It should be designed to be introduced into the primary cooling section to achieve stabilization and immobilization. The bulk foam contained in the formwork after quenching stabilization must be separated from the form immediately after exiting the turnnel kiln and then slowly cooled to 20 to 40 ° C in a secondary cooling furnace controlled at a cooling rate of at least 1 ° C / min. Annealing to finally obtain a block of foam. If the formwork is made of metal, slow cooling without bulk form after the quenching stabilization has a big difference in the coefficient of thermal expansion of the form and the coefficient of thermal expansion of the foam. Since it is impossible to obtain a foam of, it is necessary to cool the foam only slowly after removing the formwork. Therefore, the conditions of slow cooling are particularly important because the bulk foams are relatively large in size compared to spherical foams.

<Example 1>

After 1000g of waste LCD glass generated from the LCD panel production line was added to a ball mill with 2.5L of pure water without any pretreatment, it was hydrated for more than 24 hours, and then separated into finely divided waste LCD glass solids and filtrate. And waste LCD glass having a particle size of 44 μm or less. 0.5 parts by weight of PVA was added to the hydrated waste LCD glass powder based on 100 parts by weight of hydrated waste LCD glass and mixed well. Based on 100 parts by weight of the hydrated glass powder in the mixed powder of the waste LCD glass powder and the molding binder, 3.0 parts by weight of crystalline graphite, 3.0 parts by weight of sulfate and 6.0 parts by weight of carbonate were added and mixed well. A raw powder mixture is prepared for producing the foam. The raw material powder mixture is kneaded (slump 0) by adding water to the extent that the raw material powder mixture becomes a dough, and is pressed to granulate to an average diameter of 1.0 mm and a density of about 1.3 g / cm ³ . The granulated raw powder mixture is placed in a die and pressurized to about 2 kg / cm ² . The prepared formwork is cube-shaped, 15 cm wide, 15 cm long and 10 cm high. The inner wall of the carbon powder and MgO powder is applied with water and dried. A formwork containing the granulated raw powder mixture is introduced into the Turnnel kiln. Turnnel kiln is a continuous furnace consisting of drying and preheating in the temperature range of 650 ° C at the inlet of the kiln, foamed plastic part adjusted to the temperature of 960 ° C at the center, and cooling part for cooling by quenching at 500 ° C. The granulated raw powder mixture is foamed and fired at the foam firing part in the tunnel kiln for a predetermined time, and then separated from the mold immediately after exiting the tunnel kernel after passing through the cooling part. The calcined block was slowly cooled and annealed to a temperature range of 40 in a cooling furnace controlled at a cooling rate of 1 ° C./min to finally obtain a block. The bulk foam thus prepared was the same as in FIG. 1 and its density was 0.16 g / cm ³ and the compressive strength was 101.4 N / cm ² to 126.2 N / cm ² . In addition, the extraction rate of indium and tin in the filtrate after the hydration of the waste LCD glass was confirmed to be low, but less than 5% by weight of the amount of indium and tin contained in the waste LCD glass.

<Example 2>

To 1000g of waste LCD generated in LCD panel production plant, 2.5L of 0.05 M hydrochloric acid solution was added as it is without special pretreatment and placed in a ball mill for hydration reaction for more than 24 hours, and then the finely divided LCD glass solids were separated from the filtrate. The glass powder is neutralized and washed to obtain a hydrated LCD glass powder. The moisture content at this time is 1.1% or more and the particle size of the LCD glass is 44 μm or less. To 100 parts by weight of this hydrated waste LCD glass powder, 10 parts by weight of kaolinite powder ground to 44 µm or less as a molding binder was added and mixed well. To the mixed powder mixed with the waste LCD glass powder and the molding binder, 2.5 parts by weight of crystalline graphite, 4.0 parts by weight of sulfate and 6.0 parts by weight of carbonate were added as a foaming aid, based on 100 parts by weight of the hydrated LCD glass powder. Mix to make a raw powder mixture. The raw powder mixture is kneaded by adding the amount of water to which they are kneaded (slump 0), pressurized and granulated to a size of less than 1 mm, and the granulated raw powder mixture is again rolled at a high speed in a disk-shaped molding machine and averaged. It is molded into a spherical shape having a diameter of 7 mm. At this time, the spherical compact is compacted while rolling at a high speed until the density can reach 1.2 g / cm ³ or more. Spherical compacts with a density of at least 1.2 g / cm ³ are charged into a rotary kiln adjusted to 600 ^o C, dried and preheated. The dried and preheated molded body is charged with a small amount of MgO powder as a release agent into a high temperature rotary kiln whose temperature at the exit side of the furnace is adjusted to 960 ° C., and the molded product is plastically foamed by allowing the molded body to stay at the center of the furnace for a predetermined time. In addition, the foam is introduced into a rotary kiln adjusted to a temperature of 520 ° C. to rapidly quench and stabilize, and finally, slowly cooled and annealed to a temperature of 40 ° C. in a cooling furnace controlled at a cooling rate of 1 ° C./min to finally obtain a spherical foam. The prepared spherical foams were the same as those of FIG. 2 and their average density was 0.53 g / cm ³ and the compressive strengths were varied depending on the density of the spherical foams. The values ranged from 200 N / cm ² to 350 N / cm ² . . After the hydration reaction of the waste LCD glass, the indium and tin components in the filtrate were found to be 73 wt% and 54 wt% of the indium and tin present in the waste LCD glass, respectively.

<Example 3>

1000g of waste LCD glass produced in the LCD panel production line is added with 2.5L alkaline aqueous solution added with NaOH as 1wt% without special pretreatment and put into a ball mill for more than 24 hours. After the hydration reaction, the finely divided LCD glass solids are separated from the filtrate and neutralized and washed to quantitatively remove the remaining alkali components in the LCD glass powder. At this time, the water content is 2.8% or more and the particle size of the LCD glass is 44㎛ or less. The hydrated waste LCD glass powder was added to 10 parts by weight based on 100 parts by weight of the hydrated waste LCD glass powder as a molding binder, and mixed well. As a foaming aid, 2.0 parts by weight of crystalline graphite, 4.0 parts by weight of sulfate and 7.0 parts by weight of carbonate were added based on 100 parts by weight of hydrated waste LCD glass powder to prepare a raw material powder mixture. It is kneaded (slump 0) by adding water to kneading the raw material powder mixture and granulated to a size of less than 1mm in diameter. The granulated raw powder mixture is again formed into a spherical shaped body having an average diameter of 8 mm and a density of 1.2 g / cm ³ or more in a disk-shaped molding machine. The spherical shaped body is placed in a low temperature rotary kiln with an outlet at 600 ^o C and dried and preheated. The dried and preheated shaped bodies together with a small amount of MgO powder as a release agent are charged into a high temperature rotary kiln controlled at 980 ° C. and fired and foamed. The foam was introduced into a rotary kiln whose temperature at the furnace inlet was adjusted to 500 ° C to stabilize the quenching, and finally slowly cooled and annealed to a temperature of 40 ° C in a cooling furnace controlled at a cooling rate of 1 ° C / min. To get a foam. The spherical foam prepared in this way is as shown in Figure 3, the average density was 0.61g / cm ³ and the compressive strength exhibited a wide variety of values measured from 230 N / cm ² to 380 N / cm ² .

<Example 4>

1000g of waste LCD glass produced in the LCD panel production plant is added with 2.5L of pure water without any special pretreatment and placed in a ball mill for more than 40 hours. After the hydration reaction, the finely divided LCD glass solids are separated from the filtrate to obtain a hydrated waste LCD glass powder having a water content of 1.0% or more and a particle size of 44 μm or less. Kaolinite powder having particles of 44 μm or less as a molding binder is added to the hydrated waste LCD glass powder based on 100 parts by weight of hydrated waste LCD glass powder, and mixed well. To the mixed powder of the waste LCD glass powder and the molding binder, 3.2 parts by weight of crystalline graphite, 3.1 parts by weight of sulfate and 6.2 parts by weight of carbonate were added and mixed well based on 100 parts by weight of the waste LCD glass powder hydrated as a foaming aid. Constitute a powder mixture. The raw powder mixture is added to the raw powder mixture (slump 0) and pressurized to granulate the raw powder mixture to a size of less than 1 mm in diameter. The granulated raw powder mixture is again formed into a spherical shape so as to have an average diameter of 8 mm or less and a density of 1.2 g / cm ³ in a disk-shaped molding machine. The spherical shaped body is charged into a low temperature rotary kiln with an outlet side of 600 ^° C and dried and preheated. The dried and preheated molded body is charged with a small amount of MgO powder as a release agent into a high temperature rotary kiln adjusted to 960 ° C., and the molded product is allowed to stay at the center of the furnace for a predetermined time to be fired and foamed. The foam is then quenched and stabilized at a temperature of 500 to 600 ° C. and then separated from the release agent powder to charge only the foam as it is, and the form is introduced into the tunnel kiln. The prepared formwork is cuboid, 15 cm wide, 15 cm long and 10 cm high. The inner wall of the carbon powder and MgO powder is poured with water and dried. Turnnel kiln is composed of a cooling unit that allows the temperature of the center to be adjusted to 980 ℃ without a separate preheating unit to ensure that the spherical foam is heat-sealed and to stabilize and fix the structure at 550 ℃ temperature after fusion. Take the formwork out of the turnnel kiln through the stabilized cooling section. Subsequently, the bulky foam formed by fusion of the spherical foam is slowly cooled and annealed to a temperature of 40 ° C in a cooling furnace controlled at a cooling rate of 1 ° C / min to finally obtain a bulky foam. In this case, further foaming of small spherical foams that were unfoamed together with heat fusion was able to proceed. As the fusion time increased, the density was less than 0.4 g / cm ³ . The bulk of the foam produced through the above process is the same as that of Figure 4 and the density was 0.41g / cm ³ and the compressive strength of the embodiment 1 to make the bulk directly foam of 200 N / cm ² to 238 N / cm ² It may have a higher strength than the case.

<Example 5>

A spherical foam having an average diameter of 3 mm to 10 mm or less produced by the process described in claim 1 is mixed by using a certain amount of cement as a binder according to a desired density and specification, and cured for a predetermined time by molding. When curing is completed, the mold is separated from the mold to obtain a plate-shaped or lattice-shaped or light-shaped foam. The bulk of the prepared foam is as shown in Figure 5, the density was 0.91g / cm ³ and the compressive strength was not measured because it is directly affected by the type and amount of cement used.

<Example 6>

The spherical foams obtained in Examples 2 and 3 were tested for their applicability as media for water treatment. Of the spherical foams prepared in the above embodiment 5mm to less than 10mm in diameter, filling density 0.6g / cm ³ More than 1.0 g / cm ³ Less than spherical shaped bodies were used as media to treat the effluent and to evaluate the ability to reduce contaminants. The experimental method was conducted by an indoor experiment by a reactor and the analysis items were set to SS, BOD, COD, TN, and TP. To this end, three types of filtration media that have been used effectively have been tested under the same conditions for the target pollutants under the same conditions. As a result, the other three media showed treatment capacity of 35.6% to 67.9% with respect to SS, but the spherical foam of the present invention showed 70.3% and 38.4% to 46.5% of BOD with respect to BOD. Although 55.3% of the spherical foams of the present invention showed treatment capacity of 25.7% to 38.7% of the other three media for COD, the spherical foam of the present invention was 57.8% and 27.3% of the other three media for TN. To 36.9%, but the spherical foam of the present invention was 30.5%, TP of the other three media showed a treatment capacity of 34.3% to 47.4%, but the spherical foam of the present invention was 51.2% The spherical foams made of the waste LCD glass of the present invention, respectively, showed very excellent performance as media for water treatment.

The present invention has been described with reference to certain preferred embodiments, but the present invention is not limited to the above-described embodiments and those skilled in the art without departing from the concept of the present invention. Various changes and modifications are possible by.

Figure 1a Figure 1b is a mass photo of the mass produced by the proposed process.

Figure 2a Figure 2b is a spherical polymorph photograph produced by the proposed process.

Figure 3a Figure 3b is a photograph of spherical polymorph produced by the proposed process.

Figure 4a Figure 4b is a photograph of the mass of the mass produced by heat fusion spherical foam produced by the proposed process.

Figure 5 is a mass of polycystic body produced by using the spherical foam produced by the proposed process as a cement binder.

Claims (14)

 Hydration reaction is performed on the waste LCD generated during the manufacturing, processing and disposal of electronic products related to the LCD panel after use. Hydration reaction allows the waste LCD glass to have a moisture content of more than 0.67%. A hydration reaction process of waste LCD glass (step 1-1), wherein the glass is wet-pulverized into fine powder having an average diameter of 50 µm or less, and the indium and tin components of the waste LCD glass are extracted to the hydration solution; As the hydration reaction of step 1-1 proceeds, the hydration solution containing indium and tin components extracted from the waste LCD glass is extracted, and the wet LCD powder powder wet-pulverized and hydrated with fine powder having an average diameter of 50 µm or less is separated. Separating and washing (step 1-2); Process for adding foaming agent to make raw material powder mixture by adding foaming aid composition to hydrated waste LCD glass powder with particle size 50㎛ or less, water content (moisture content) 0.67% or more of waste LCD glass prepared in steps 1-1 and 1-2 above (Step 2); In order to increase the density of the raw material mixture for maximizing the sintering effect during foaming and firing to lower the foaming firing temperature for the raw material powder mixture obtained by the above two steps, a sintering aid, molding binder and water are added to the raw powder mixture and averaged. Granulation step (3 steps) of granulation by pressure extrusion to a diameter of about 0.5 mm to 3 mm; Forming process of making the granulated raw material powder mixture obtained by the above 3 steps, the spherical shaped body having a diameter of 3 mm to 30 mm or less and a density of 1.2 g / cm ³ to 3.0 g / cm ³ in a disk-shaped molding machine (Step 4-1). ), or, In order to obtain a bulky inorganic foam from the granulated raw powder mixture obtained by the above three steps, the bulk shaped compacts which are pressure-molded into a bulk to have a density of 1.2 g / cm ³ to 3.0 g / cm ³ are contained in a die or A charging step (4-2) of placing the granulated raw powder mixture directly in a die and compacting the granulated raw powder mixture so that the density of the granulated raw powder mixture is 1.2 g / cm ³ to 3.0 g / cm ³ ; The spherical molded product obtained in step 4-1 is introduced into a rotary kiln for drying and preheating, or the granulated raw powder mixture, which is compacted in a die or formwork containing the bulk molded product in step 4-2 and pressurized, is introduced into a tunnel kiln and dried. And drying and preheating processes (5 steps) for preheating: Spherical or bulky low thermal expansion high strength mineral Forming a foam (step 6); And Stabilizing and annealing the low thermally expandable high-strength inorganic foam produced by the firing and foaming process (7 steps); Method for producing a low thermal expansion high-strength inorganic foam using the waste LCD glass comprising a. In claim 1, The foaming aid is a foaming aid with respect to 100 parts by weight of the hydrated waste LCD glass powder, and 0.1 to 3.5 parts by weight of high-temperature degradable crystalline graphite carbon, 0.5 to 10.0 parts by weight of sulfate, and carbonate A method for producing a low thermal expansion high strength inorganic foam using waste LCD glass, characterized in that 0.5 part to 10.0 parts by weight of all or part thereof is added. In claim 1, The sintering aid and the molding binder is PVA, starch, water glass, kaolin powder, basalt powder, bentonite powder, characterized in that at least one of the use of a low-expansion inorganic foam using a waste LCD glass. In claim 1, Magnesia powder, alumina powder, and the like on the outer surface of the molded body of step 4-1 in order to prevent adhesion between the foams foamed during the foaming step or the foam adhered to the rotary kiln wall after the step 4-1 and before the step 5-1. A method for producing a low-expandable inorganic foam using waste LCD glass, characterized by applying at least one release agent of carbon powder. In claim 1, Magnesia powder, alumina powder, smelting furnace slack powder on the inner wall surface of the formwork just before or after step 4-2 in order to make it possible to easily separate the coarse foam from step 1-1 to step 6 Alternatively, an appropriate amount of water is added to the mixture of at least one of the clays mixed at a ratio of 1.5 to 3 parts by weight with respect to 1 part by weight of carbon powder (graphite powder) to make a sludge state, which is applied as a release agent on the inside of the formwork. A method of producing a low thermal expansion inorganic foam using waste LCD glass. In claim 1, The preheating and firing foaming process for the production of spherical foam in the 5th and 6th process is composed of one rotary kiln or two rotary kilns, and after the foaming, the seventh stabilization and slow cooling process is a rotary process consisting of five and six steps. A method for producing spherical low thermal expansion inorganic foam using waste LCD glass, characterized in that it is made of one or two rotary kilns separate from kilns. In claim 1 or 6, In the case of using the two rotary kilns used in the quench stabilization and slow cooling process in relation to the manufacturing process of the spherical foam in the step 7, the primary rotary kiln directly connected to the rotary kiln in the foaming process is 500 ^o C to 650 ^o C. The second rotary kiln is an annealing heat treatment furnace that is slowly cooled to room temperature to 50 ^o C. The inside of the furnace is installed so that the spherical foam outer surface is polished and the pores of the foam are exposed to the surface. A method for producing a spherical low-expansion inorganic foam using waste LCD glass. In claim 1, The firing and foaming temperature of the sixth step is a spherical molded body is adjusted to a temperature of less than 850 ^o C to less than 1100 ^o C, the bulk foam using the formwork is adjusted to a temperature of less than 850 ^o C to less than 1100 ^o C A method for producing a low thermally expandable inorganic foam using waste LCD glass, characterized by using kiln. In claim 1, By using the cement as a binder for the spherical foam of a predetermined diameter prepared by the above-described process to form a lightweight body in the desired shape or form by combining in a formwork, The process presented above  Hydration reaction is performed on the waste LCD generated during the manufacturing, processing and disposal of electronic products related to the LCD panel after use. Hydration reaction allows the waste LCD glass to have a moisture content of more than 0.67%. A hydration reaction process of waste LCD glass (step 1-1), wherein the glass is wet-pulverized into fine powder having an average diameter of 50 µm or less, and the indium and tin components of the waste LCD glass are extracted to the hydration solution; As the hydration reaction of step 1-1 proceeds, the hydration solution containing indium and tin components extracted from the waste LCD glass is extracted, and the wet LCD powder powder wet-pulverized and hydrated with fine powder having an average diameter of 50 µm or less is separated. Separating and washing (step 1-2); Process for adding foaming agent to make raw material powder mixture by adding foaming aid composition to hydrated waste LCD glass powder with particle size 50㎛ or less, water content (moisture content) 0.67% or more of waste LCD glass prepared in steps 1-1 and 1-2 above (Step 2); In order to increase the density of the raw material mixture for maximizing the sintering effect during foaming and firing to lower the foaming firing temperature for the raw material powder mixture obtained by the above two steps, a sintering aid, molding binder and water are added to the raw powder mixture and averaged. Granulation step (3 steps) of granulation by pressure extrusion to a diameter of about 0.5 mm to 3 mm; Forming process of making the granulated raw material powder mixture obtained by the above 3 steps, the spherical shaped body having a diameter of 3 mm to 30 mm or less and a density of 1.2 g / cm ³ to 3.0 g / cm ³ in a disk-shaped molding machine (Step 4-1). ), or, In order to obtain a bulky inorganic foam from the granulated raw powder mixture obtained by the above three steps, the bulk shaped compacts which are pressure-molded into a bulk to have a density of 1.2 g / cm ³ to 3.0 g / cm ³ are contained in a die or A charging step (4-2) of placing the granulated raw powder mixture directly in a die and compacting the granulated raw powder mixture so that the density of the granulated raw powder mixture is 1.2 g / cm ³ to 3.0 g / cm ³ ; The spherical molded product obtained in step 4-1 is introduced into a rotary kiln for drying and preheating, or the granulated raw powder mixture, which is compacted in a die or formwork containing the bulk molded product in step 4-2 and pressurized, is introduced into a tunnel kiln and dried. And drying and preheating processes (5 steps) for preheating: Spherical or bulky low thermal expansion high strength mineral Forming a foam (step 6); And Stabilizing and annealing the low thermally expandable high-strength inorganic foam produced by the firing and foaming process (7 steps); A method for producing a low-expandable inorganic foam using waste LCD glass, characterized in that. In claim 1, In the process of obtaining the hydrated and finely divided waste LCD glass of steps 1-1 and 1-2, it has an additional process in which indium or tin, which is a valuable metal component present in the waste LCD glass, can be extracted and recovered. A method for producing a low expandable inorganic foam using waste LCD glass. In claim 1, A small amount of hydrochloric acid was added to the hydration solution before the hydration so that extraction of indium or tin, which is a valuable component present in the waste LCD glass, was effectively performed in the process of obtaining the hydrated finely divided waste LCD glass of steps 1-1 and 1-2. A method for producing a low thermally expandable inorganic foam using waste LCD glass, wherein the inorganic acid such as nitric acid, sulfuric acid, phosphoric acid, acetic acid, formic acid, etc. is hydrated using an aqueous solution. Hydration reaction is performed on the waste LCD generated during the manufacturing, processing and disposal of electronic products related to the LCD panel after use. Hydration reaction allows the waste LCD glass to have a moisture content of more than 0.67%. A hydration reaction process of waste LCD glass (step 1-1) in which the glass is wet-pulverized into fine powder having an average diameter of 50 µm or less, and the indium and tin components in the waste LCD glass are extracted to the hydration solution; As the hydration reaction of step 1-1 proceeds, the indium and tin components present in the waste LCD glass are extracted, and the hydrated solution containing the liquid is wet-pulverized and hydrated into fine powder having an average diameter of 50 μm or less, and then separated. Separation process (step 1-2) to wash; Process for adding foaming agent to make raw material powder mixture by adding foaming aid composition to hydrated waste LCD glass powder with particle size of 50㎛ or less, water content (moisture content) 0.67% or more prepared in steps 1-1 and 1-2 (Step 2); Sintering aid, molding binder and water are added to the raw material powder mixture to increase the density of the raw material mixture for maximizing the sintering effect during foaming and firing to lower the foaming firing temperature for the raw material powder mixture obtained by the above two steps. An granulation step (3 steps) of granulation by pressure extrusion to about 0.5 mm to 3 mm; Forming process of making the granulated raw material powder mixture obtained by the above 3 steps, the spherical shaped body having a diameter of 3 mm to 30 mm or less and a density of 1.2 g / cm ³ to 3.0 g / cm ³ in a disk-shaped molding machine (Step 4-1). ), or, In order to obtain a bulky inorganic foam from the granulated raw powder mixture obtained by the above three steps, the bulk shaped compacts which are pressure-molded into a bulk to have a density of 1.2 g / cm ³ to 3.0 g / cm ³ are contained in a die or A charging step (4-2) of placing the granulated raw powder mixture directly in a die and compacting the granulated raw powder mixture so that the density of the granulated raw powder mixture is 1.2 g / cm ³ to 3.0 g / cm ³ ; The spherical molded product obtained in step 4-1 is introduced into a rotary kiln for drying and preheating, or the granulated raw powder mixture, which is compacted in a die or formwork containing the bulk molded product in step 4-2 and pressurized, is introduced into a tunnel kiln and dried. And drying and preheating processes (5 steps) for preheating: Spherical or bulky low thermal expansion high strength mineral Forming a foam (step 6); A step (seventh step) of charging the spherical or bulky foam discharged from the rotary kiln through the above six steps without being introduced into a subsequent heat treatment step (7th step); In the seventh step, the formwork containing the spherical or blocky foam is smoothly introduced into the turnnel kiln adjusted to 700 ^o C to 950 ^o C, and the spherical or blocky foam is joined by a heat fusion method to form a large plate or lattice. Forming a foam (step 8); Separating the plate- or lattice-shaped foam from the mold (step 9); And Performing a slow cooling and heat treatment process of the plate- or lattice-shaped foam having passed the nine steps (step 10); A method of producing a plate- or lattice-shaped inorganic foam having low thermal expansion, high strength using waste LCD glass, characterized in that it comprises a. In claim 12, Magnesia powder, alumina powder, smelting furnace slag powder or clay on the inner wall surface of the formwork immediately before the 4-2 process or just before the 7th process so that the plate- or lattice-like foam having undergone the 9th process can be easily separated from the formwork. A waste, characterized in that an appropriate amount of water is added to a mixture in which at least one of them is mixed at a ratio of 1.5 to 3 parts by weight with respect to 1 part by weight of carbon powder (graphite powder) to form a sludge, which is applied as a release agent on the inside of the formwork. Process for producing low thermally expandable inorganic foam using LCD glass. delete

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