Production of vacuum expanded glass. RU patent 2513809.
| Method of making heat-insulation blocks / 2513807 Invention relates to production of heat-insulation building materials with closed porosity. Binder solution is prepared first via combined wet grinding of silicate lumps with silica modulus of 1-3 and a silica-containing component with ratio of dry components of 1:1-1:5 and water to solids ratio of 1:1.2-1:4 at temperature of 70-110°C until complete dissolution of the silicate lumps. The silica-containing component is then added to the binder solution until a moulding compound with moisture content of 5-35% is obtained. The moulding compound is granulated and dried. The raw granules are placed in a mould and heated to foaming temperature, followed by annealing. Cooling is carried out at a rate of not more than 4°C per minute. |
| Method of foamed glass production / 2502686 Invention relates to production of foamed glass. Glass material and foaming agent are mixed. As foaming agent applied is powder of water purification slag, which is formed as a result of removal of hardness salts in the process of water preparation at thermal electric power plants. Bulk density of slag constitutes 850-900 kg/m3. Foaming agent constitutes from 5 to 20% of glass material volume. Obtained mixture is laid in forms, foamed, annealed and cooled. |
 Method of foam-glass manufacturing / 2490219Invention relates to heat-insulating materials, in particular to foam-glass. Crushed zeolite-containing ore with NaOH water solution with the following ratio, wt %: zeolite-containing ore - 75-80, NaOH - 15-20. Raw mixture is granulated, granules are dried, kept in the air for 1-4 days. Foaming is performed at temperature 680-800°C. |
| Method of producing heat-insulation facing material based on foamed glass / 2485058 Invention relates to technology of silicates and production of articles from foamed glass. The method of producing heat-insulation facing material based on foamed glass with a decorative and protective coating, wherein raw materials ground to the required particle size: scrap glass or packaging or sheet glass granulates and a foaming agent: coal, soot, limestone or chalk, are mixed to obtain a foaming mixture, foamed and fired in a furnace. Deposition of the protective and decorative coating, which consists of a mixture of scrap glass or glass granulate in amount of 0.40-0.50 pts.wt, liquid glass in amount of 0.40-0.50 pts.wt, is carried out on finished foamed glass blocks cooled to temperature of 20-25°C; the layer is moulded by wetting, followed by heat treatment of the coating at temperature of 100-120°C for 2-4 hours and firing at temperature of 500-600°C for 5-15 minutes. |
| Method of activating mixture for producing foamed glass / 2483035 Invention relates to a method of activating a mixture for producing foamed glass. Starting components for producing the mixture are first ground to the required dispersion of the material - glass, which contains SiO2, Al2O3, RO, R2O, Fe2O3 and soot. The step for mixing components involves activation of the mixture for producing foamed glass by further addition of solutions of alkali metal sulphates S2- 0.75-6H to the composition of crude materials. Concentration of alkali metal sulphates in the mixture ranges from 5 to 10 wt % in excess of 100%. Components of the mixture are in the following ratio, wt %: SiO2 - 61.0-73.0, Al2O3 - 0.5-3.0, RO - 10.0-15.0, R2O - 13.0-17.0, Fe2O3 - 0.1-0.3, C - 0.6-3.0, S -5.0-10.0. Further, the mixture is foamed and fired in a furnace in order to obtain the end product - foamed glass. |
| Method of producing foamed glass and mixture for producing foamed glass / 2478587 Invention relates to production of heat-insulating materials. Condensed microsilica, sodium hydroxide and hot water at 80-90°C are mixed in a reactor for 10-15 minutes until formation of liquid glass. The liquid glass is then mixed with expanded pearlite for 10 minutes. The mixture is foamed in the closed volume of a metal mould at temperature of up to 780°C for 0.5-1 hours. The finished articles are annealed at temperature ranging from 780°C to 360°C for 1 hour, followed by cooling on air. The following components are used to prepare the mixture for producing foamed glass, wt %: expanded pearlite with density of 75-100 kg/m3 - 20; condensed microsilica - 28; sodium hydroxide - 12; water - 40. |
| Method of producing heat-insulating material and mixture for production thereof / 2478586 Invention relates to production of heat-insulating building materials. Amorphous silicic rock, sodium hydroxide and hot water at 80-90°C are mixed in a reactor for 10-15 minutes until formation of sodium hydrosilicate. The obtained liquid is then mixed with expanded pearlite for 10 minutes. The mixture is foamed in the closed volume of a metal mould at temperature of up to 700°C for 0.5-1 hours. The finished articles are annealed at temperature ranging from 700°C to 360°C for 1 hour, followed by cooling on air. The mixture for producing heat-insulating material contains the following components, wt %: expanded pearlite with density of 75-100 kg/m3 - 20; amorphous silicic rock - 28; sodium hydroxide - 12; water - 40. |
| Method of making expanded glass / 2463262 Invention relates to production of fillers to be used in compositions of heat insulation materials and coats. Liquid glass is mixed with magnesium carbonate in amount of 3% to 10% of total volume of mix. The latter is dries at 5-40°C and minced to 3-100 mcm-grain size. Then, glass bearing powder is treated at 150-500°C to comply with preset foaming, curing and cooling level. In production of expanded glass to be used in composition of fire-insulation coat expansion ratio is set to 10% of initial volume while heat treatment is carried out at lower temperatures of preset temperature range. In production of expanded glass to be used in composition of heat-insulation coat expansion ratio is set to 1000% of initial volume while heat treatment is carried out at higher temperatures of preset temperature range. |
| Method of producing foamed glass / 2459769 Invention relates to production of foamed glass. Powdered mixture based on crushed glass and mineral substance - talc, is prepared, with the following ratio of components in wt %: talc 2-8, glass - the balance. The mixture is heated in a metal mould at foaming temperature of 720-780°C, followed by annealing. |
| Method of producing foamed glass / 2455245 Invention relates to heat insulation structural materials. The mixture is prepared from scrap glass and additives: carbon, barium sulphate, sodium sulphate and aluminium hydroxide. The scrap glass is first ground in two steps. At the first step, the scrap glass is ground in a hammer mill to particle size 10-15 mm. At the second step the scrap glass is ground in an impact-kinetic mill to particle size 0.04-0.1 mm. The additives are ground to particle size 0.04-0.06 mm. The mixture is foamed at temperature 860°C and annealed for 49 hours at temperature from 520°C to 30°C. |
| Method of preparing raw mix for fabricating glass foam / 2255057 Invention relates to building materials with low values of heat conductivity and density. Preparation of raw mix comprises stirring glass-forming components and powderlike additives containing gasifier among other components. Glass-forming component utilized is sodium and/or potassium silicate aqueous solution taken in amounts 30 to 70% and silicate-reactive additive is fine powder of broken glass. Stirring is carried out at temperature not superior to 70°C and, after stirring, resulting mix is subjected to heat treatment at temperature between 450 and 550°C for a period of time long enough to completely remove of water, including chemically bound one, after which mix is cooled and powdered. |
| Method of preparing blend for fabricating glass foam / 2255058 Invention relates to building materials with low heat conductivity and density values. Preparation of blend comprises stirring glass-forming components and powderlike additives containing gasifier among other components. Glass-forming component utilized is sodium and/or potassium silicate aqueous solution taken in amounts 50 to 70% and silicate-reactive additive is fine powder of broken glass. Stirring is carried out at temperature not superior to 70°C and viscous-flow mix is thermally treated at 450-550°C to completely remove of water, including chemically bound one, after which mix is cooled and ground into power with particle size at most 60-70 μm. |
| Glass foam fabrication method / 2255059 Invention relates to building materials with low values of heat conductivity and density. Fabrication of glass foam comprises heating powderlike blend with carbon-containing gasifier to foaming temperature, pausing at this temperature to complete foaming process, and subsequent cooling. Blend utilized is a cooled raw mix ground to powdered state, which is prepared via heat treatment of mixture of sodium and/or potassium silicate alkali aqueous solution and silicate-reactive additive, in particular fine broken glass powder and carbon-containing gasifier, at 450-550°C until removal of water, including chemically bound one, is completed. According to invention, content of sodium and/or potassium silicate alkali aqueous solution amounts to 30-70%, mixing is carried out at temperature not superior to 70°C, and foaming temperature of blend lies within a range of 750 to 830°C. |
| Glass foam fabrication method / 2255060 Invention relates to building materials with low heat conductivity and density values. Fabrication of glass foam comprises preliminary heat treatment at temperature below foaming temperature of starting mixture prepared from broken glass powder, carbon-containing gasifier, and sodium and/or potassium silicate aqueous solution, pausing at this temperature to complete foaming process, and subsequent cooling. Starting mixture is prepared at temperature not superior to 70°C by consecutively mixing sodium and/or potassium silicate aqueous solution (30-70%), not sorted broken glass powder (25-65%), and carbon-containing gasifier (4-9%), after which mixture is treated at 450-550°C until removal of water, including chemically bound one, is completed. Resulting product is cooled and then heated to foaming temperature (750-830°C). |
| Foaming mixture and a method of production of a modular foamed glass with the mixture use / 2265582 The invention is pertaining to the methods of production of effective functional heat-insulating materials with a low value of their thermal conduction and densities, in particular, to the methods of production of the vitreous silicate materials, namely, the foamed glass with usage of a foaming mixture and is dealt with utilization of the vitreous wastes produced as a result of the household vital activity of people, and also the technogenic products of the people household activity and industrial origination. The problem of the offered invention is production of an effective functional modular foamed glass with improved operational characteristics: an apparent density - 0.15-0.45 g/cm3, high heat-insulating properties λ = 0.06-0.08 W/(m·°K), volumetric water adsorption of no more than 10%, capable to withstand mechanical loadings of no less than 7 kg/cm2; utilization of alkaline silica-alumina and borosilicate vitreous wastes of different kinds of glass, both individual glass and mixtures of glasses. The foaming mixture for production of the modular foamed glass includes I in mass %): active carbon-black with a specific surface area of 50-100 m/g -20-70; sulfates of alkaline-earth elements - 10-40, carbonates of alkaline-earth elements - 20-40. The method of production of the modular foamed glass with a usage of the foaming mixture provides for: a dispersion of the utilized glassbats up to the specific surface of 15000-20000 cm2/g; an addition to 95.0-99.8 mass % of the dispersed glassbats of 0.2-5.0 mass % of the foaming mixture; agitation at humidity of 1.2-1.5 mass %; granulation into particles with the diameter of no more than 2000 microns; a filling of the granules in the mold and their subcompaction up to a porosity of 0.35-0.55; sintering at the temperature of 600-750°C; a foaming at the temperature of 800-900°C, a hardening by temperature decrease to 550-650°C at the rate of 200°C /minute and annealing at the temperature of 500-600°C. |
| Method of production of calibrated granulated foamed glass / 2272005 Initial raw mixture is made from aqueous alkaline solution of sodium silicate in the amount of no less than 30-70 mass-% and broken glass powder of arbitrary chemical composition in the amount of 25-65 mass-%. This raw mixture is subjected to heat treatment to dehumidified state and powder-like charge and aqueous dispersion are prepared in presence of plasticizing agents. Product thus obtained is dried at dried at temperature of 450-500°C, pelletized and is held at foaming temperature within range of 800-850°C. |
| Foam decoration manufacturing method / 2276659 Invention relates to foam production technology and can be used manufacture of foam decoration. Invention aims at simplifying production technology and obtaining effective decorative heat-retention material for out-door and in-door facing of residential and industrial constructions. Method according to invention consists in grinding commercial broken glass to specific surface 5000-7000 cm2/g followed by moistening to moisture 8%. Thus obtained material is compacted on press at 20 MPa. Resulting samples are subjected to watering during thermomoist processing to form silanol water, which would favor swelling during heat treatment. Thermomoist processing conditions: temperature rise for 2 h, ageing at 85-95°C for 6 h, and cooling to 15-25°C for 3 h. Watered samples are coated with decorative layer using flooding technique and then subjected to heat treatment at 800°C followed by annealing. Finally obtained samples show density 350 kg/m3, bending strength 28 kg-force/cm2 and decorative glossy water-impermeable film 0.2-0.3 mm thick. |
 Method of production of foamed glass mat and device for realization of this method / 2299185Proposed method consists in applying the gas-forming agent on continuous band of film glass which is placed in mold layer by layer for obtaining the mat of required thickness. Then glass is heated and is foamed. Device proposed for realization of this method has two shafts, vacuum drum, unit for application of gas forming agent, spreader and mold. Unit for application of gas-forming agent may be made in spreader rollers. |
 Tunnel furnace / 2310616The invention is pertaining to the tunnel furnaces for production of the block lightweight building materials. The technical result of the invention consists in the increased furnace capacity. The tunnel furnace is made in the form of the double-level tunnel. Each level has the zones of foaming, quenching, stabilizing and annealing, the heaters power adjustment both from above and from below of each zone. In the tunnel furnace there are dollies for relocation of the molds. The lower heaters of each level are disposed in the form of two longitudinal rows, between which there is the central guide as the support for the dollies. The central guide is made in the form of the U-beam. Each dolly is supplied with the additional wheels: the central wheel mounted vertically and the front wheel mounted horizontally engaged from the inside with the horizontal ledge and the lateral ledges of the central guide. |
 Method of manufacturing of longlasting foamglass / 2332364Invention relates to method of manufacturing heat-insulating, foamy materials. Pieces of glass are melted, melted mass is degassed by keeping it at temperature 1450°C for 10-60 minutes and are cooled to 950-1200°C. Overheated water steam, obtained from degassed water is passed through melted mass for blowing of great number of bubbles of different diameter from melted glass. Glass bubbles are cut off into form with formation of blocks, baked at temperature 450-600°C and cooled. |
FIELD: process engineering.
SUBSTANCE: invention relates to production of heat-insulation foamed materials. Glass powder is heated in helium medium at 0.2-0.5 MPa to 800°C. Molten glass mass is held in heating zone to saturation with helium. Then, gas pressure is decreased to 0.01-0.1 kPa to allows foaming of glass medium by dissolved gas. Rarefaction in gas is maintained to cool down said glass mass to vitrification stage.
EFFECT: low heat conductivity foamed glass with rarefied helium in its bubbles.
2 cl
The invention relates to the field of production of heat insulating foam that can be used in energy-saving construction, cryogenic equipment, for heat insulation of refrigerators and other industries that connected with thermal protection. The method describes the preparation of foam glass, then, which is a gas at a pressure below atmospheric that provides a low thermal conductivity of the material.
There are ways in which finely ground silica glass (particles 2-10 microns) is mixed with gasifier (such as carbon), the resulting uniform mechanical mixture (mixture) is served in forms or on a conveyor belt in the tunnel kiln. As a result of heating up to 800-900°With particles of glass softened up viscous-liquid state, and the carbon is oxidized with gaseous CO2 and CO, which churn viscous-liquid glass mass and form foam glass [1].
Known methods do not allow to obtain materials with thermal conductivity below 0,04-0,05 W/(m·K).
Known methods of obtaining vacuum foam.
A method of obtaining vacuum insulating panels from solid porous material (Pat. US 5989371, 1999; Pat. US 6266941, 2001). Porous basis panel formed from a mixture containing powder of polyurethane foam and a filler in the form of powder thermoplastic resin. The mixture is placed in a mould and subjected to compression compression environment in vacuum at temperature not below the glass transition temperature of polyurethane and temperature not below melting of thermoplastic resin, and then sealed in packaging material, inside of which will remain a vacuum, and porous base supports the specified form of the panel. As filler can be used mica flakes, plastic film. As thermoplastic resins can be used resin styrene. In forming can be applied vibration. A similar method of obtaining vacuum thermal insulation material, but without pressing described in U.S. patent number 5889067.
According to the U.S. patent №7166348 doughy material ekstragiruyut in an area of low pressure to induce the formation of pores and get a porous material with open porosity, the surface of which is then coated packaging barrier film at a pressure of about 10 PA.
It is known that the heat transfer through a porous material is provided through coherent solid phase and through disjointed or malovanyy gas phase filling gas bubbles. thermal conductivity of the gas phase depends on the length of the free run of gas molecules, i.e. the gas pressure. Open porosity, used in a patent-analogs, characterized by the presence of open pores, consisting of a network of capillaries, channels and cracks, communicating with each other and with the surface of a material, i.e. the gas phase forms a cohesive region.
The disadvantage of this method of obtaining vacuum panels is that the preservation of low pressure of gas in the material with an open porosity very problematic. thermal insulation properties of the material easily broken if damaged packaging barrier membranes.
The closest to the technical nature of the present invention is a method of manufacturing of insulating foam materials on patent RU №2332364 on the application number 2006101087 based on passing through the molten glass, superheated steam. Through the molten glass, miss superheated steam at a temperature of 950-1200 C, obtained from substances capable of cooling to be adsorbed on the walls closed bubbles, foam material is extruded in the form cool with decreasing pressure of vapor bubbles below atmospheric through condensation, are taken out from moulds and annealed through gradual cooling in thermal insulation Cabinet. Taken as a prototype.
The disadvantages of this method is the technological complexity of receipt of foam glass, especially sparging melt superheated steam. The porosity of foam glass, resulting in a known way, is low, as the degree of rarefaction of gas in the pores that prevent you from achieving low thermal conductivity.
To solve this task, you must get the material from the closed porosity with gas pressure in the gas bubbles of foam glass below atmospheric.
To do this in a known way to obtain the vacuum of foam glass, which includes heating of a glass powder and foam molten glass, glass powder is heated to the melting temperature in the environment of helium at a gas pressure of 0,2-0,5 MPa, can withstand the molten glass melt in the heating zone, carrying out of saturation of glass gas by adsorption. Then dump the excess gas pressure and pump the remaining gas vacuum pump to the pressure 10-100 PA, making a foaming glass of dissolved helium. Maintaining the achieved negative pressure in the gas medium, cool foamed glass mass to the stage of vitrification. After cooling to room temperature obtain a block of foam disjointed porosity, which can be machined.
Signs of way, shared with analogues and prototype:
a) particles crushed glass is heated to the point of melting;
b) in the molten glass is injected substance, capable to form embryos disjointed gas bubbles (centres of steam formation). The method according to the invention of such centers of steam formation is dissolved helium;
in) foamed glass mass is cooled to a stage of transition;
g) receive a finite gas pressure in the pores below atmospheric.
Signs of method according to the invention, which distinguish it from the prototype method, in which the melt glass is blown ferry:
a) instead of water steam for the formation of bubbles use soluble gas - helium;
b) the stage of melting is performed under gas pressure;
the prototype of the vapor pressure of water in the pores below atmospheric achieved by linking water with vysokochastotnyi molecules in the walls of bubbles. The method according to the invention of the vacuum in the pores is achieved at the expense of the glass melt in a vacuum.
The method is realized in several steps as follows. Powder glass is placed in a gas environment under excessive pressure of several atmospheres, and then subjected to thermal treatment. Under the influence of heat glass melts and gas, located in the pores dissolve in a viscous molten glass. Solubility of helium in the molten glass, at approximately hundred times higher than that of argon and other inert gases, which makes it a good foaming agent.
Implementation of the method is illustrated by an example.
Example: For reception of foam glass use a fine glass powder with a particle size less than 200 microns. Glass powder can be obtained, for example, the melting of the charge of the following composition,% Mas.:
lead acetate
87,2boric acid
10,0quartz sand
2,8The charge is maintained at a temperature of about 900 C to the hour. The obtained glass mass is cooled, crushed in a mill and sift through a sieve 200 microns.
Stage 1. A portion of glass powder was filled in the form, to resist high temperatures, such as graphite crucible. The form was placed in a container that can withstand high pressure, such as autoclave. In the vessel, provided the environment helium at high pressure through the supply of gas from the cylinder through a gas reducer.
Stage 2. Glass powder in the pores of which is soluble gas helium at a pressure of 0.2 to 0.5 MPa (approximately 2 to 5 ATM), put in the oven, heated to melting temperature, which is approximately 600-800°N
Stage 4. Then stravovani excessive pressure of gas through the gas valve, and the remaining gas was pumped booster pump performance, providing foaming at the expense of expansion contained in the glass melt dissolved gas.
Stage 5. Foam mass is cooled in a vacuum to the stage of transition.
The process works as follows. At the stage of melting fine powder filled with gas under pressure. Melting particles of glass moving in viscous plastic condition, and helium pressure saturates the melt. The particles of glass powder fuse together, the gas is located in the powder form of gas bubbles, due to the developed surface of contact of gas-liquid part of the gas intensively absorbed by the glass and is dissolved in melt. The method does not require the addition of any substances-foamers, as is done in traditional methods of production of foamed glass as centers of steam formation is dissolved in a viscous glass helium. The feeding of the viscous glass gas depends on the properties of the glass used for making glass powder, temperature, viscosity of melt and selected experimentally. You then reduce the pressure of the gas environment through leakage of gas to atmospheric pressure and pumping using a booster pump dissolved helium is expanding and remains in the glass melt in the form of a rarefied gas inclusions. A rapid discharge of pressure and sufficiently low melt viscosity, which can be regulated temperature, dissolved in a glass of gas molecules act as centers of steam formation, foaming, i.e. in the glass produced many disjointed between him since. In low, so-called technical, vacuum pressures below 1 mm Hg(0,01-0,1 kPa) thermal conductivity of such time lower than thermal conductivity then, for example, carbon dioxide, education which is often used for the foaming of foam glass in ways analogous. After cooling to the stage vitrification formed a solid porous mass in the pores containing helium at a pressure below atmospheric.
The technical result is a heat insulating material - foam glass low thermal conductivity, the bubbles of which is sparse helium. Calculated coefficient of thermal conductivity of the material is about 0,02 W/(m·K), which is lower than the material with the same porosity, obtained by the method similar.
Sources of information
1. Demidovich B.K. foam Glass. - Minsk: Nauka I Tekhnika, 1975.
2. Pat. US 5989371, 1999; Vacuum heat-insulating panel and method for producing the same.
3. Pat. US 5889067, 1999; Open cell rigid polyurethane foam and method for producing the same and the method for making vacuum insulation panel using same.
4. Pat. US 6266941, 2001. Vacuum heat-insulating panel and method for producing the same.
5. Pat. US 7166348, 2007. Core material for vacuum heat insulation material, and vacuum heat insulation material.
6. Patent RU №2332364. Publ. 27.08.2008. The prototype.
1. The method of obtaining the vacuum of foam glass, which includes heating of a glass powder and foam molten glass, wherein the glass powder is heated in an environment of helium at a pressure of 0,2-0,5 MPa up to the melting temperature, preferably up to 800 C, stand molten glass mass in the heating zone to saturation of helium, then reduce the pressure of the gas medium to 0.01 and 0.1 kPa, providing a foaming glass of dissolved gas, after which support the achieved depression in gas environment and glass mass is cooled up to the stage of transition.
2. The method according to claim 1, characterized in that the size of particles of glass powder does not exceed approximately 200 microns.