KR20170091053A - Process For Manufacturing Sound-absorbing Insulation Foam With The Recycling Of Waste Borosilicate Glass And The Sound-absorbing Insulation Foam Made By The Process - Google Patents

Abstract

The present invention provides a method for manufacturing sound absorbing and insulating foam by recycling waste borosilicate glass, which can prevent environmental pollution, save costs and have excellent mechanical characteristics. The method for manufacturing the sound absorbing and insulating foam comprises the steps of: (1) wet-grinding the waste borosilicate glass; (2) removing impurities from the grinded glass; (3) drying the glass where the impurities are removed at 20-60C for 5-15 hours and separating finely grinded glass with particle size of 63 m or less; (4) mixing a foaming agent and a pore control additive with the finely grinded glass; and (5) plasticizing the mixture, wherein the foaming agent is made by adding 3.0-6.0 parts by weight of at least one among Na_2Co_3, CaCO_3 and Na_2SO_4, which are a non-carbon foaming agent and 0.1-0.5 parts by weight of expandable graphite, which is a carbon foaming agent with respect to 100 parts by weight of the finely grinded glass.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for manufacturing a sound-absorbing sound-insulating foam by recycling waste borosilicate glass, and a sound-absorbing insulation foam produced by the method,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sound-absorbing sound insulation foam by recycling waste lung borosilicate glass and a sound-absorbing and sound insulating foam produced by the method, and more particularly to a method for manufacturing a foamed glass having sound- The present invention relates to a sound-absorbing and sound insulating foam having excellent heat resistance and sound absorption properties, which comprises a pulverizing step of waste glass, an additive mixing step for controlling pores, a foaming and calcining step, and a heat treatment step.

The thermal power plant produces steam by burning coal or petroleum, and uses it to generate power. In the combustion process of coal or petroleum, sulfur dioxide (SO ₂ ) or sulfuric acid gas (SO ₃ ) is inevitably generated due to sulfur contained in coal and petroleum. If the generated SO ₂ or SO ₃ is directly discharged into the atmosphere, it will cause severe air pollution. Therefore, the desulfurization step of the wet processing step is performed at the stage before the discharge of the combustion gas for removing the sulfur dioxide (SO ₂ ) or the sulfuric acid gas (SO ₃ ) in the exhaust gas. However, the exhaust gas that has been subjected to the desulfurization process contains a considerable amount of sulfuric acid or sulfuric acid in the moisture generated by the wet treatment process, and thus the calcitic chimney melts down during the exhaust process, There is also the risk that the chimney will collapse when used. In addition to these problems, the amount of gas exhausted when coal and oil are burned is so great that the noise caused by the churning and friction at the time of discharge is a serious problem that hinders the power generation operation. The problems of the operation of these thermal power plants are as follows: In 2009, there have been cases of large damage caused by the collapse of the power plant zipli in India. In Korea, it is reported that the complaints are seriously caused by the noise generated in the stack. The damage caused by such noise is a social problem that needs to be solved as soon as the noise of the apartment floor as well as the power plant becomes a big social problem of our society today.

In order to solve this problem faced by thermal power plants, we have studied the sound absorbing materials that can resist the noise problem with strong chemical resistance so as to protect the stack, and developed products using nickel and metal. However, there is a problem that the unit price is expensive and the chemical resistance is poor. Pittsburgh, USA developed a sound absorbing material using borosilicate glass with strong chemical resistance to overcome this problem, and it was effective in protecting short time chimney from chemical erosion due to high chemical resistance of borosilicate glass, but it was not put to practical use. The reason for this is that a costly manufacturing cost for the production of borosilicate glass as a raw material glass for foaming is a problem, but a more important problem is that the mechanical strength of the borosilicate foam produced is too low, The durability was seriously low due to wear and tear, so that it could not be put to practical use. Therefore, it is necessary to redevelop the built-in sound-absorbing sound insulation to solve the above problem.

The problem of noise is a big problem not only in the residence but also in the actual industrial field. Especially in the case of thermal power plants, the noise generated by the process has a great impact on the employees of the power plant as well as the local residents. Three years ago, residents' conflicts around the SRF cogeneration plant were a major example of the noise and odor of the Sejong cogeneration plant. The noise of the thermal power plant is particularly problematic because the location of the power plant is not far from the noise of the residential area. The Busan Combined Cycle Power Plant located in the center of Pusan city provides more than 60% of the electric power needed in Busan, but it is not a gratitude to citizens, but environmental pollution and noise. As the capacity of the generator increases, the noise of the thermal power plant is increasing due to the increase in the capacity of the equipment, which leads to lower work efficiency and labor hygiene. One of the main causes of the noise of the power plant is due to the friction with the stack wall while the burning exhaust gas of coal and oil burned for power generation passes through the stack (chimney). This noise at the chimney due to the exhaust gas from the thermal power plant has an adverse effect on the working environment and everyday life of the residents as well as the power generation workers, causing industrial disaster.

At present, thermal power plants have made various efforts to reduce the noise generated from such stacks. Typically, foamed aluminum, which acts as a sound absorbing material, or special metal foams are used for lining the walls of stacks.

However, a sound-absorbing agent made of a metal foam has a second problem that a metal foam easily corrodes due to a large amount of acid component generated in a wet desulfurization process of an exhaust gas, and even safety problems such as collapse of a stack occur, In reality, there is no perfect response.

It was proposed as one of solutions to solve the problem of corrosion due to the acidic exhaust gas and the problem of noise, and a sound absorbent made of corrosion resistant borosilicate glass foam was used as the lining material of the stack. The use of sound absorbers made of borosilicate glass foam has an excellent effect in protecting the wall of the stack from the acid component contained in the exhaust gas due to the inherent high corrosion resistance of the borosilicate glass as well as the original function of reducing the noise It is considered to be a very desirable alternative in theory. In reality, however, the borosilicate glass foams proposed so far have a mechanical strength of too low, which makes it difficult to continuously use the borosilicate foam glass block due to the extremely low durability of exhaust gas emission at high flow rates. have. The solution to this problem can be obtained by developing a process capable of producing a borosilicate foamed glass block having sound absorption properties with high strength and high durability.

Borosilicate glass is a glass containing boric acid, which is much more expensive to manufacture than soda-lime glass and requires a high-temperature production process. Therefore, it is more economical to make foam by using soda lime glass when it is used as general building thermal insulation material or as a sludge lining material. However, in order to be used as a sound absorbing material for lining of a thermal power plant stack which requires corrosion resistance, Glass must be used to make the foam. In addition, the borosilicate glass foam should have high mechanical strength so as to have high durability to withstand the flow of high-speed exhaust gas in a thermal power plant stack, and can easily obtain raw materials for manufacturing borosilicate glass which is relatively more expensive than soda lime glass It is expected that this would be the most desirable process for the production of borosilicate foamed glass foams for coal fired power plants.

Borosilicate glass has been used as a glass container for chemical containers because it has higher corrosion resistance and mechanical strength than soda lime glass. However, it has been used as panel glass for flat panel displays in recent years. Recently, the market for flat panel displays Its use is enormous. With the use of this enormous borosilicate glass, the amount of gasses generated is never too small.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram of a waste LCD panel among the perovskic acid glasses used in the present invention. FIG.

Especially, since the LCD display has exceeded the initial supply stage, the generation of waste LCD panel glass is increasing rapidly because of addition of process waste in the production process as well as after-use product. According to a study by the Standard Resource, 30% of the total amount of electrical and electronic products discarded in the EU in 2004 is increasing by 15% or more every year since 2005 as LCD products. Currently, Panel glass has reached over 50,000 tons per year. However, at present, the waste borosilicate glass is incinerated or buried without special recycling.

LCD panel glass, which is borosilicate glass, is an important recycling target, and recycling of waste borosilicate glass in order to achieve the recycling rate according to the resource recycling method is a national task.

The waste borosilicate glass that can be used as a raw material for the manufacture of borosilicate glass foams is not only glass for waste LCD panels. Automobile glass that is landfilled and disposed of without special recycling measures is also covered. At present, the number of scrap cars in Korea is more than 800,000 units, and the incidence rate is expected to increase by 3.5% per annum to exceed 830,000 units by 2015. In the automobile recycling, metals, nonferrous metals, plastics and tire rubber are compressed and shredded Although it is easy to recycle by heat recovery, waste glass of automobile is treated by landfill and incineration, and its economic value is evaluated to be relatively low. Currently, in Korea, automobiles that are scrapped in accordance with the Law on the Recycling of Electrical and Electronic Products and Automobiles (hereinafter referred to as the "Resource Circulation Act") will achieve a recycling rate of 85% or more from 2009 by reuse and recycling of parts, etc. . Particularly, reuse of parts has become a useful means for resource conservation, environmental preservation, and CO ₂ reduction.

Such waste glass for automobiles and glass for waste LCD panels are borosilicate glass in chemical composition. Therefore, in any case, if a breakthrough recycling plan is set up, it will be a raw material that can be applied to the mutual process. In Korea, which is a display powerhouse, Korea will need to make a breakthrough recycling plan as soon as possible. .

Korean Unexamined Patent Publication No. 2002-0078137 discloses a method in which a clay paste mixture is mixed with a total porosity capable of contacting neighboring bubbles due to cohesion of bubbles to 30 to 90% to form a continuous gap, and then the bubbles are coagulated The present invention relates to a ceramic sound absorbing material having continuous openings by drying and firing in a state in which a continuous gap is maintained. If the temperature is not precisely controlled during the clay firing, cracks will occur, resulting in poor merchantability. Should be. Therefore, mass production is difficult due to such a problem, and there is a problem that the sound absorption characteristics are not known because the pore control technology is not presented.

In addition, Korean Patent No. 785652 discloses that since an organic material having a foaming agent as a vegetable or animal foam is used, its binding force with a ceramic powder is deteriorated and it can not be used where strong physical characteristics such as the inner wall of a factory chimney are required. And it is difficult to control the sound absorption characteristics.

In addition, U.S. Published Patent Application No. 2005-0031844 discloses a technique for producing a foam based on bottle glass (soda lime glass). Since it is based on soda lime glass, it has high economic value and high added value in terms of recycling waste resources, And has characteristics of sound absorption and adiabatic property. However, since it is based on a bottle glass, corrosion resistance, which is the limit of its own material, becomes a problem, which limits its use in a severe atmosphere.

In addition, U.S. Published Patent Application No. 2005-0031844 relates to a method for producing a foam from a bottle glass (soda lime glass) which is a natural glass such as an unexpanded pearlite ore and an expandable pearlite, The use of the material is limited in extreme situations due to the weak corrosion resistance of the material itself.

Therefore, in the present invention, waste LCD panel glass, which is a waste borosilicate glass, is recycled as a recycling method for waste borosilicate glass which is disposal and incineration, We intend to develop a process for producing high strength borosilicate foamed glass block which has high corrosion resistance and sound absorption properties that can be used and which complements low durability of existing borosilicate foamed glass.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an epoch-making environmentally-friendly recycling method of waste plastic glass or waste LCD glass based on waste borosilicate glass.

It is another object of the present invention to provide a technique for manufacturing a sound-absorbing and noise insulating foam having a color for interior and exterior use that is specialized in preventing interlayer noise.

Another object of the present invention is to provide a process for producing a borosilicate glass foam for laminating a thermal power plant having high chemical resistance and sound absorption performance.

In order to solve the above problems, the present invention provides a method of manufacturing a sound-absorbing sound insulation foam by recycling waste borosilicate glass, comprising the steps of (1) wet pulverizing waste borosilicate glass, (2) removing impurities from the pulverized glass (3) separating the glass from which the impurities have been removed at 20 to 60 DEG C for 5 to 15 hours and separating the glass finely divided to 63 mu m or less; (4) mixing the blowing agent and the pore controlling additive into the finely divided glass And (5) firing the mixture, wherein the blowing agent is added to 100 parts by weight of the finely divided glass with non-carbon foaming agents Na ₂ CO ₃ , CaCO ₃ and Na ₂ SO ₄ And 3.0 to 6.0 parts by weight of at least one of graphite and expanded graphite (Expandable graphite) are added to the mixture.

Also, the present invention is characterized in that the pore- SiO ₂ , B ₂ O ₃ and Al ₂ O ₃ And 0.05 to 0.15 parts by weight of the pore-controlling additive is added to 100 parts by weight of the finely divided glass.

Also, the present invention is characterized in that the calcining step comprises: a preheating step of placing the mixture in a mold and heating the mixture to a temperature of 500 to 600 DEG C for 30 to 120 minutes; B) foaming and firing at 900 to 1100 ° C for 20 to 60 minutes; C) quenching at 550 to 650 ° C for 8 to 12 minutes, and then slowly cooling to room temperature at a time of 10 hours or more.

Further, the present invention is characterized in that 0.03 to 0.05 part by weight of a ceramic pigment can be further added to 100 parts by weight of the finely divided glass powder in the mixing step (4) in order to manifest various colors in the sound-absorbing and sound insulating foam. ≪ / RTI >

In addition, the ceramic pigment of the present invention is composed of cobalt-based CoCO ₃ and potassium-based K ₂ SO ₄ Which is characterized in that it can be included.

Further, the present invention provides a method for manufacturing a sound-absorbing and sound insulating foam characterized in that the forming die is made of stainless steel and the lubricating sibling containing the boron nitrate component is applied inside the forming die.

The present invention also provides a sound-absorbing and heat-insulating sound-absorbing foam made by any one of the above-described manufacturing methods.

In addition, the present invention relates to a sound-absorbing and sound insulating foam having a strong refractory chemical characteristic against salt water corrosiveness, an open porosity of 30 to 50% and an open porosity of which increases the sound absorption rate and a peak sound absorption rate of 0.4 to 0.9 The sound-absorbing heat-insulating foam being characterized by being located at a predetermined position.

The present invention can prevent environmental pollution caused by recycling of discarded waste LCD glass, reduce costs, and achieve high mechanical strength and open pore shape, thereby providing a sound-absorbing sound insulation function.

Further, the present invention provides a sound absorbing material foam block which is excellent in economic efficiency, high mechanical strength, excellent chemical resistance and sound absorbing function, and can be used not only in the use of a chimney lining material of a thermal power plant but also in an industrial building interior material and a domestic building interior material, It can be used as an interlayer noise preventing agent for an apartment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a photograph of a waste LCD panel among the perovskic acid glasses used in the present invention. FIG.
FIG. 2 is a diagram illustrating a process for manufacturing a sound-absorbing and heat-insulating sound-absorbing foam by recycling waste borosilicate glass according to the present invention.
FIG. 3 is a graph showing the relationship between the glass transition temperature (TGA) and the glass transition temperature (TGA) at room temperature to 1000 ° C. for glass particles separated by particle size of 100 mesh or less after wet pulverization in order to determine the optimal particle size of the raw glass to be used in the foam manufacturing process of the present invention. ) Is a plot of the resultant value.
Fig. 4 is a photograph of a colored foam when a pigment is added to the colored foam of the present invention. Fig.
FIG. 5 is a diagram illustrating a detailed process of the firing step in the process of manufacturing the bumpy sound-deadening foam of the present invention.
Fig. 6 is a photograph of the sound-absorbing and sound insulating foam of the embodiment of the present invention.
FIGS. 7-9 are measurement values of the sound absorption rate of the foam having open porosity (P ₀ ) of 30%, 35%, and 45% open pores of the embodiment of the present invention.
10 is a measurement of the sound absorption rate of a foam having a 15% open pore, which is a comparative example.
11 is a photograph showing the chemical resistance characteristic of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted so as to avoid obscuring the subject matter of the present invention.

As used herein, the terms " about, " " substantially, " " etc. ", when used to refer to a manufacturing or material tolerance inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

[0001] The present invention relates to a method for manufacturing a sound-absorbing and sound insulating foam by recycling waste borosilicate glass, which comprises: (1) wet pulverizing waste borosilicate glass; (2) removing impurities from the milled glass; (3) separating the glass from which the impurities have been removed at 20 to 60 ° C for 5 to 15 hours, and then finely dividing the glass to 63 μm or less; (4) mixing the blowing agent and the pore controlling additive into the finely divided glass, and (5) firing the mixture.

The glass used in the present invention is characterized in that the borosilicate glass is added to the borosilicate glass to lower the transparency but the thermal expansion rate is low. For this reason, it does not break even when it is heated or cooled. Products commonly called heat-resistant glasses are borosilicate glass. Another important feature of borosilicate glass is high corrosion resistance and high chemical resistance. For this reason, borosilicate glass is used as a device for physics in beakers, measuring cylinders, and the like. Therefore, it would be the most favorable advantage in the case of producing a sound-absorbing sound-insulating agent as a lining agent for a stack especially intended for this study.

Examples of the borosilicate glass used as borosilicate glass include automobile glass, display glass, physicochemical apparatus, tableware, and glass fiber used for special purposes. The dual display glass is of interest in terms of ease of separation from other materials and amounts that are discarded.

Accordingly, the present invention is to recycle waste LCD glass, which is a waste borosilicate glass, to find an efficient foaming temperature condition, a specific optimal heat treatment condition, and to produce a foam having sound absorption characteristics through pore control.

Hereinafter, each step will be described in detail.

Dry grinding is a time-consuming and costly process because the pulverized LCD panel is pulverized by using a ball mill. However, it is difficult to recover smooth glass because resin, plastic and oil components are attached on the borosilicate glass plate of the waste LCD panel. That is, when these components are present in the borosilicate glass raw material to be foamed in a large amount, the result of a good foaming reaction can never be obtained.

Thus, the present invention wet pulverizes waste borosilicate glass. The wet grinding is carried out by putting the sample and water in a large ball mill and pulverizing in a wet atmosphere with a grinder for about 12 hours.

This is because the removal of the impurities may be caused by the presence of various impurities in addition to the pure glass depending on the application in which the glass is used. Glasses that are not dissolved in water but are sunk can easily be separated by using the properties of insoluble glasses which have a high specific gravity and are insoluble in water.

Glass isolated from impurities is a mixture of finely divided glass with various sizes of granules. Of these, only the finely divided glass having a particle size of 63 μm or less can be selected using 230 mesh.

Table 1 below shows the size of the separable fine particles according to the mesh number.

mesh No. 100 130 170 200 230 270 325 Particle size (㎛) 150 112 91 75 63 53 45

 Prior to screening the finely divided glass with a particle size of 63 μm or less, it is dried at 20 to 60 ° C. for 5 to 15 hours to remove moisture remaining in the wet grinding. At temperatures above 60 ° C additional refinement may be necessary since the glass powders are easily hardened again.

FIG. 3 is a view showing a result of thermogravimetric analysis (TGA) of glass particles of various sizes by size.

The analysis showed that the weight loss was small even though the particle size of the glass powder was increased with increasing temperature, but the weight loss was obvious in the case of the powder with relatively large particle size. That is, when the size of the particles is less than 200mesh, the weight loss is less than 1.5%, but in the case of the glass powder having the size in the range of 130 to 170mesh, it is 3%. In the case of the glass powder having the size in the range of 100 to 130mesh, Respectively.

 This weight reduction means that there is an impurity which is thermally decomposed in the glass powder, and this impurity can be predicted to be a plastic or a resin component. The fact that there is no reduction in weight as the particle size of the glass is small means that the incorporation of such impurities is small, which is a phenomenon that can be conceived from the characteristics of plastics, resins and glasses. In other words, glass is a noncrystalline inorganic material and it is easy to undifferentiate by impact. However, polymer materials such as plastic and resin are not easily differentiated by impact. The amount of residual polymeric material such as plastic or resin in the glass powder, which is the raw material for foam production, directly affects the foaming and firing reaction. Because these components are almost completely decomposed at the temperature range in which the foaming and firing proceeds, the amount of the calcining is considerably increased in the decomposition process, which causes a problem in the process. In addition, the content of the remaining carbon components is reduced as a carbon- And this will be a factor that directly affects the pore control as a sound absorbing material in the present invention.

In this respect, proper wet grinding conditions will be necessary to efficiently separate the glass component, plastic or resin components, and recover only the glass component. According to the results of FIG. 3, the weight loss of glass powder of less than 325mesh was less than 1%, and that of the range of 230 to 270mesh was less than 1.3%.

As a result, in the present invention, the glass powder obtained under the wet grinding condition is judged to be usable as a raw glass for producing a foamed glass block if glass having a size of 230 mesh (63 탆) or less is used as a condition for suppressing the incorporation of impurities such as plastic and resin do.

Next, the blowing agent and the pore controlling additive are mixed with the selected glass microfine having a size of 63 탆 or less. The production of borosilicate glass foams having a sound-absorbing function by using pulverized borosilicate glass can be achieved by preparing a borosilicate glass foam for thermal insulation which is once formed of closed pores without sound absorption function.

Regardless of the shape of the conventional foamed glass, most of the pores formed are closed pores. For such a structural reason, the foamed glass is mainly used as a thermal insulation material. Borosilicate glass would also be a borosilicate foam glass with closed pores, unless an attempt is made for a particular structural change.

Therefore, by using the pulverized borosilicate glass, the borosilicate glass foam is made to be foamed, and at the same time, the closed pores formed in the foaming process are controlled to be the open pores to obtain the desired borosilicate glass foam having the sound absorbing function . Therefore, the production of a borosilicate glass foam having a sound absorbing function should be based on a process for producing a borosilicate glass foam having closed pores, so the present invention has been made on the basis thereof.

The foaming agent can be classified into a carbon foaming agent and a non-carbon foaming agent.

Carbon blowing agents are the most basic blowing agents. Therefore, the most basic component to foam the recovered glass components from waste LCD panels is the carbon blowing agent. The amount and amount of carbon species are very important because the amount of gas generated for foaming and the foaming mechanism vary depending on the type and amount of foaming agent. The reaction temperature range of carbon is important for effective foaming. If the reaction of the carbonaceous material is started before the softening temperature of the glass is different from the reaction temperature of the carbonaceous material, the gas will escape before the glassy material surrounds the foaming agent. If the reaction temperature is higher than that, stable foaming it's difficult. Therefore, in the present invention, expandable graphite is used to achieve the foaming of waste LCD panel glass. Expandable graphite is considered to be effective for foaming because it has the characteristic that the layer is expanded several hundred times when heat is applied.

Non-carbon foaming agents should be made of expandable graphite carbon foaming agent used in blowing LCD LCD panel glass, because the amount of gas is not enough and it is difficult to achieve smooth foaming, so that a sufficient amount of gas can be discharged by mixing non-carbon foaming agent.

Accordingly, Na ₂ CO ₃ , CaCO ₃ , and Na ₂ SO ₄ are used as non-carbon foaming agents capable of discharging carbon dioxide gas and sulfide gas in order to effectively discharge the gas and effectively generate foaming. When these foaming assistants are melted at the foaming temperature, the Na component acts as a flux and lowers the softening temperature of the raw material, and the decomposed CO ₂ and SO ₃ gases accelerate the foaming of the glass.

The blowing agent may be added to 100 parts by weight of the finely divided glass with non-carbon foaming agents Na ₂ CO ₃ , CaCO ₃ and Na ₂ SO ₄ , And 0.1 to 0.5 parts by weight of expandable graphite (carbon graphite) are added.

As described above, the foaming can be made successful by i) the composition and the particle size of the raw material glass, and ii) the selection and combination of the foaming agent. However, the foam having such a foaming mechanism has almost the pores formed as the closed pores and has the use of the heat insulating material of good performance, but the foam having the sound absorbing performance of the present invention is not formed.

In order for the foam to have a sound-absorbing performance, the pores formed in the foam must be made of open pores. Therefore, in order to produce a foam having a sound-absorbing performance, it is necessary to form the pores with open pores through separate pore control as well as foam formation.

Therefore, in order to control the pores generated by the foaming agent, it is necessary to mix the pore controlling additive in addition to the foaming agent.

In addition, in order to increase the open porosity of the porous object, it is necessary to increase the size of the pores and the number of the pores by the blowing agent, and to prevent the open pores from being closed by using the pore control additive.

Generally, the composition of the pore-controlling additive should be different depending on the composition of the glass. Therefore, in order to control the size and shape of the pores of the glass foam, the composition ratio of the sample is most important. Because the formation of open pores is formed at high temperatures by the carbon blowing agent and various blowing agents penetrating the surface tension of a molten or softened glass sample wrapped by the gas produced by the chemical reaction. Therefore, the amount of gas produced varies according to the composition ratio of the sample, and various forms of foam appear depending on the melting point and the viscosity reaction state of the sample.

 In order to produce a sound absorbing material through pore control, the shape of the pore should be in the form of an open pore as described above. To do this, the viscosity of the first molten glass must have a certain value. If the viscosity is too low, it is likely that the pores from the gas will close quickly by the molten sample and return to the form of clogged pores. However, too high viscosity increases the surface tension of the molten specimen, and it has a lot of energy required for foaming, and it is not energy efficient, so proper control is needed. Second, the pore can be controlled by manipulating the state of the molten or softened sample.

The glass samples contain various types of oxides including SiO ₂ . This means that the melting point of the sample does not exist at a constant temperature but differs depending on the constituents of the material and that the state of the molten sample exists in various ways. That is, as the temperature increases, certain components first vaporize, or oxidation and reduction reactions occur. Even in a molten state, a trace amount of a component may not melt or vaporization may occur due to reaching a boiling point. Since the melting or softening state of the glass component varies, various types of foaming processes may occur by manipulating the components of the sample.

Therefore, it is first necessary to confirm that these changes affect the formation of pores through the change of existing constituents contained in the raw glass components. If the metal oxide or the salt not contained in the glass sample is contained as described above, it is difficult to predict the melting point operation and the separation and precipitation phenomenon occurs. As a result of the uneven distribution of the raw materials, It is easy to get up.

In the present invention, the porosity controlling additive may be SiO ₂ , B ₂ O ₃ or Al ₂ O ₃ .

The SiO ₂ serves to lower the softening point of the glass. Especially, the melting point of the LCD glass is 1100 ~ 1300 ° C, which is considerably higher than the melting point of the soda lime glass used as the raw material of the conventional foam glass, It is a component that can lower the softening point. In fact, it accounts for the largest proportion of waste LCD panel glass, and has the function of stabilizing and homogenizing glass structure through bonding with other oxides to reduce or prevent moisture absorption. The addition of other oxides plays a major role in controlling the actual SiO ₂ content and controlling the size and shape of the pores. If the content of SiO ₂ is insufficient, the melting point may become high, which may lead to difficulties in foaming or the durability of the finished foamed glass is likely to be low. In the actual foaming process, the arrangement of the raw material components is a very important determining factor, and the ratio of SiO ₂ content as the core of the glass component is very important.

The B ₂ O ₃ is known to be dissolved in boron trioxide at 577 ° C. It has a boiling point of 1,500 ° C. or more but exhibits a considerable vapor pressure even at 1,000 ° C. This can increase the size and number of bubbles during foaming. In the production of glass, a small amount of 1 to 1.5% may be added as a flux, and the thermal efficiency of the process can be increased by lowering the softening temperature of the raw material. In the case of B ₂ O ₃ , it acts to reduce thermal stress in the foaming process. It is expected that the addition of boric acid of this role will reduce the closing speed of the open pores generated in the foaming process and will control the pore size. However, excessive addition reduces the durability of the foamed glass and forms a massive foam.

The Al ₂ O ₃ is a kind of stabilizer oxide, which serves to inhibit phase separation and dissolution (crystallization) and increase chemical durability. Excess Al ₂ O _3, however, increases the viscosity and can have a technically bad effect. The content of Al ₂ O ₃ required in the borosilicate glass decreases with the increase of SiO _{2 and with} the decrease of NaO ₂ and the increase of alkali metals. Al ₂ O ₃ can be supplied as Al ₂ O ₃ or Al (OH) ₃ . Sometimes, but can also use the _{kaolinite (Al 2 O 3 · 2SiO} 2 · 2H 2 O) in this case SiO ₂ also added, especially iron exists and iron should also note that vitrification is easily one good to pore control technology of cellular glass It can be a raw material.

In addition, metal oxides such as ZrO 2, MgO, BaO, and ZnO can be considered as components for controlling pores. This can lead to durability and low expansion of the glass as a raw material for the glass process, and it can produce foam blocks having different physicochemical properties. However, if the amount of such oxides is large, the melting point of the raw material may be increased to inhibit the production of seamless foam blocks.

In the present invention, the porosity controlling additive is SiO ₂ , B ₂ O ₃ and Al ₂ O ₃ , 0.05 to 0.15 parts by weight of the pore-controlling additive is added to 100 parts by weight of the finely divided glass.

In the present invention, 0.03 to 0.05 part by weight of a ceramic pigment may be further added to 100 parts by weight of the finely divided glass powder in the mixing step (4) in order to manifest various colors in the sound-absorbing sound insulating foam.

Currently, the color of borosilicate foam glass used as a sound absorbing material, including the heat insulating material that has been produced and used commercially as a heat insulating material throughout the world, is only black. This is because only a black foam is produced because a foaming agent is a carbon foaming agent. In the present invention, the borosilicate foam that can be produced exhibits a good sound-absorbing performance, which is considered to be sufficiently usable as a sound-absorbing agent. In this case, when a sound absorbing agent having a good performance is used as an indoor sound absorbing agent, it is considered that a foam having essentially black only can have a wide variety of uses if it can have a white or other color. Thus, the borosilicate foam produced in black can be made into another colored foam.

As a suitable pigment which can be exhibited under the high-temperature glass foaming conditions of the present invention, an inorganic pigment capable of withstanding high temperatures is appropriate. As a result of examining economical pigments without heavy metals, CoC ₃ and K ₂ SO ₄ is most suitable for color reaction. Fig. 4 is a photograph of a colored foam when a pigment is added to the colored foam of the present invention.

FIG. 5 is a diagram illustrating a detailed process of the firing step in the process of manufacturing the bumpy sound-deadening foam of the present invention.

When the blowing agent and the pore controlling additive are mixed with the finely divided glass and the temperature and the time are controlled through the baking step, a sound-absorbing sound-insulating foam can be produced.

It is preferable that the mold used in the firing step is a stainless steel mold and the lubricant is sprayed on the mold. It should be noted that it is preferable to contain the air without contact with the outside air so as to be oxidized well.

The releasing agent is preferably a releasing agent containing a boron nitrate component. Or a commercially available release agent may be used. These release agents are very important materials for the glass to produce more stable. The foamed glass contained in the molding die is not easily separated from the molding die due to adhesion of the molten raw material sample to the molding die in the process of melting at a high temperature. Therefore, it is very important to use lubrication siblings for smooth deformation process of foam blocks.

It is preferable to use a stainless steel molding die having excellent durability so that the die is low in cost, has excellent heat resistance capable of withstanding a high temperature of 1000 DEG C or higher, has low reactivity with ceramic materials, and is easy to reuse. The most important feature of stainless steel is that it contains chromium and has strong corrosion resistance. This makes it possible to maintain the uniform surface of the mold for a long time, and it is also excellent in terms of strength, so that it can be used for various purposes and is easy to maintain.

The sample is placed in an electric furnace and fired. The sintering step includes a sintering temperature of 500 to 600 ° C. and a sintering time of 30 to 120 minutes. Through the preheating step, the thermal stabilization and foaming agent prevents rapid reaction and prevents the phenomenon of over-foaming. After the preheating step, the foaming is baked at a temperature of 900 to 1100 ° C for 20 to 60 minutes.

After the foaming and firing step is completed, the foam block is completed through the stabilization step. The stabilization step is quenching at a temperature of 550 to 650 ° C. for 8 to 12 minutes, followed by slow cooling for at least 10 hours. This is because the glass component usually has a high cooling rate after cooling the glass component to room temperature after forming at a high temperature, resulting in a residual stress due to a temperature difference.

Since the manufactured sound-absorbing sound-deadening foamed article uses a waste LCD glass composed of borosilicate glass, it has a lower unit price, sound absorption rate, chemical resistance, and mechanical strength characteristics than conventional products.

The following examples and comparative examples are referred to specifically.

※ Change of open porosity according to kind of additive and measurement of sound absorption rate

Example  One

10 kg of waste LCD panel is put into a ball mill together with 20 kg of water and pulverized for 12 hours. Then, the glass submerged in water is selected and dried at 45 ° C for 10 hours.

The dried glass powder was screened using a 230 mesh size sieve to separate only finely divided glass having a particle size of 63 μm or less. Then, 0.3 g of expandable graphite, which is a carbon foaming agent, was added to 100 g of the selected glass powder, ₂ CO ₃ , Na ₂ SO ₄ And 1.5g each addition of CaCO ₃ and, as a pore-controlling agent for the open pore-forming boric acid (B ₂ O ₃₎ is manufactured to a fine mixture was added with 10g in Southern CNA Co. BN SPRAY release agent is put on the coated stainless steel mold The open porosity and sound absorption rate of the foam obtained by foaming and sintering at 600 ° C for 30 minutes, 950 ° C for 30 minutes, followed by slow cooling for 7 hours after quenching at 600 ° C for 10 minutes are measured.

Example  2 to 6

The same conditions as in Example 1 were used, and the kind and content of the porogen is shown in Table 2.

Comparative Example

The conditions are the same as those in Example 1, and no porosity regulator is added.

division Pore regulation
additive Dry weight
[W1] (g) Wet weight
[W3] (g) W3-W1 Catcher weight [W2] (g) Sample volume (cm ³ ) density
(g / cm ³ ) W3-W2 open
Porosity
(P ₀ ) ( % ) Example  One Boric acid 10 g 52.28 70.37 18.09 16.20 261.40 0.20 54.17 33.40 Example  2 Boric acid 20g 50.20 74.35 24.15 19.50 264.20 0.19 54.85 44.00 Example  3 Silicon dioxide 10g 43.00 52.20 9.20 13.00 143.33 0.30 39.20 31.50 Example  4 20 g of silicon dioxide 40.00 53.50 13.50 14.60 148.15 0.27 38.90 34.50 Example  5 Boric acid 5g,
5 g of silicon dioxide 50.50 69.20 18.70 16.30 202.00 0.25 52.90 35.00 Example  6 10 g boric acid,
Silicon dioxide 10g 52.10 72.70 20.60 16.70 236.81 0.22 56.00 37.00 Comparative Example Not added 56.85 68.31 11.46 6.70 203.03 0.28 61.691 15.60

The open porosity of foamed glass can be calculated using KS L 3114: 2010 and calculated using the following formula.

6 is a photograph of a sound-absorbing and sound insulating soundproofing foam of the embodiment of the present invention.

As can be seen from the above Table 2, embodiments of the present invention show that the open porosity (P ₀ ) is included within the range of 30 to 50%. On the other hand, it can be seen that the porosity (P ₀ ) of the comparative example in which the porosity controlling additive is not added is 18.60%, which is considerably lower than in the examples.

7 to 9 show the sound absorption rates by frequency for the open porosity (P ₀ ) of 30%, 35% and 45% of the embodiment. It is characterized in that the peak sound absorption rate is located between 0.4 and 0.9 at frequencies between 500 and 100 Hz.

On the other hand, FIG. 10 shows that the absorption ratio of 15% open porosity of the comparative example, which is the comparative example, of the foam having 15% open pores, shows the highest absorption rate at 600 Hz but does not exceed 0.4%.

※ Chemical characteristics

The foam block is mainly used for construction materials, and the sound absorbing foam block of this task will be used especially for the reactors such as factories, power plants, or the stacks in which steam containing acid is discharged. Building materials used in these industrial parks should have excellent chemical resistance. The vapors emitted from factories and power plants are different from the normal atmospheric conditions and contain chemically unstable substances. Also, if polluted rain falls outside the building, it is easily corroded or destroyed. Therefore, it is aimed to produce a glass foam for chemical process which is resistant not only to a sound insulating insulating material but also to corrosion resistance, and analyzed for 2 weeks according to a chlorine spraying test method according to KS D 9502 through Example 1 produced by the present invention.

11 is a photograph showing the chemical resistance characteristic of the present invention. On the photograph, the foam block produced by the brine did not cause any corrosion or destruction, and no change was found. As a result, it was confirmed that the corrosion resistance was excellent.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be clear to those who have knowledge of.

Claims (8)

A method for manufacturing a sound-absorbing sound insulation foam by recycling waste borosilicate glass,
(1) wet pulverizing waste borosilicate glass;
(2) removing impurities from the milled glass;
(3) separating the glass from which the impurities have been removed at 20 to 60 ° C for 5 to 15 hours, and then finely dividing the glass to 63 μm or less;
(4) mixing the blowing agent and the pore controlling additive into the finely divided glass and
(5) firing the mixture,
The foaming agent is added to 100 parts by weight of the finely divided glass in an amount of 3.0 to 6.0 parts by weight of at least one of non-carbon foaming agents Na ₂ CO ₃ , CaCO ₃ and Na ₂ SO ₄ and 0.1 to 0.5 parts by weight of expandable graphite Wherein the method comprises the steps of:
The method according to claim 1,
The pore-controlling additive SiO ₂ , B ₂ O ₃ and Al ₂ O ₃ And 0.05 to 0.15 parts by weight of the pore-controlling additive is added to 100 parts by weight of the finely divided glass.
The method according to claim 1,
The firing step may include filling the mixture in a mold,
A) a preheating step of heating to 500 to 600 ° C for 30 to 120 minutes;
B) foaming and firing at 900 to 1100 ° C for 20 to 60 minutes;
C) quenching at 550 to 650 ° C for 8 to 12 minutes, and then slowly cooling to room temperature for at least 10 hours.
The method according to claim 1,
Wherein 0.03 to 0.05 part by weight of ceramics pigment is further added to 100 parts by weight of the finely divided glass powder in the mixing step (4) in order to manifest various colors in the sound-absorbing and sound insulating foam.
5. The method of claim 4,
The ceramic pigments include cobalt-based CoCO ₃ and potassium-based K ₂ SO ₄ Characterized in that it can be included.
The method of claim 3,
Wherein the forming die is made of stainless steel and is coated with a lubricating sibling containing a boron nitrate component in the molding die.
A sound-absorbing and sound insulating foam produced by the manufacturing method according to any one of claims 1 to 6.
8. The method of claim 7,
The sound-absorbing sound-insulating sound-absorbing foam has a strong refractory chemical property against salt water corrosion, has an open porosity of 10 to 45%, increases the open sound absorption rate as the open porosity increases, and has a peak sound absorption rate of 0.4 to 0.9 at a frequency of 500 to 100 Hz Sound absorbing sound insulation foam with characteristic.

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