CN112299770B - Heat-preservation heat-insulation fireproof plate and preparation method and application thereof - Google Patents

Heat-preservation heat-insulation fireproof plate and preparation method and application thereof Download PDF

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CN112299770B
CN112299770B CN202011217468.8A CN202011217468A CN112299770B CN 112299770 B CN112299770 B CN 112299770B CN 202011217468 A CN202011217468 A CN 202011217468A CN 112299770 B CN112299770 B CN 112299770B
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heat
particles
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mixed particles
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CN112299770A (en
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郭伟江
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    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00Other methods of shaping glass
    • C03B19/08Other methods of shaping glass by foaming
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C11/00Multi-cellular glass ; Porous or hollow glass or glass particles
    • C03C11/007Foam glass, e.g. obtained by incorporating a blowing agent and heating
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/40Porous or lightweight materials
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2201/00Mortars, concrete or artificial stone characterised by specific physical values
    • C04B2201/30Mortars, concrete or artificial stone characterised by specific physical values for heat transfer properties such as thermal insulation values, e.g. R-values
    • C04B2201/32Mortars, concrete or artificial stone characterised by specific physical values for heat transfer properties such as thermal insulation values, e.g. R-values for the thermal conductivity, e.g. K-factors
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2201/00Mortars, concrete or artificial stone characterised by specific physical values
    • C04B2201/50Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/50Reuse, recycling or recovery technologies
    • Y02W30/91Use of waste materials as fillers for mortars or concrete

Abstract

The invention discloses a heat-insulation fireproof plate and a preparation method and application thereof, belongs to the technical field of heat-insulation materials, and solves the problems that a perlite heat-insulation plate is fragile, easy to absorb water or a foamed glass heat-insulation plate in the prior art is complex in preparation process and high in cost. The heat-preservation heat-insulation fireproof plate comprises the following components in parts by weight: 50-100 parts of foamed glass particles, 50-80 parts of cement, 6-8 parts of adhesive and 30-60 parts of water; the preparation raw materials of the foamed glass particles comprise the following components in parts by mass: 1000 parts of glass powder, 300-500 parts of water glass and 5-8 parts of urea, wherein the foamed glass particles are of a composite structure and comprise porous balls and glass shells wrapping the porous balls. According to the preparation method, the foamed glass particles, the cement, the adhesive and the water are mixed to obtain a mixture; and (4) making and curing the mixture to obtain the heat-insulating fireproof plate. The heat-insulating fireproof plate and the preparation method thereof can be used for heat-insulating materials.

Description

Heat-preservation heat-insulation fireproof plate and preparation method and application thereof
Technical Field
The invention belongs to the technical field of heat-insulating materials, and particularly relates to a heat-insulating fireproof plate and a preparation method and application thereof.
Background
In the prior art, a perlite insulation board or a foamed glass insulation board is usually adopted as an indoor or outdoor insulation fireproof board.
Wherein, to the perlite heated board, because the hardness of perlite granule is low, the percent opening is high, leads to the perlite heated board that makes to have breakable, the easy scheduling problem that absorbs water.
For the foamed glass insulation board, the chinese patent application CN110183099A discloses a method for manufacturing expanded porous glass particles, in which a glass raw material, a foaming agent and an auxiliary material are ground together or separately in a grinding device; uniformly mixing the obtained substances, and preparing the mixture into particles in balling equipment; coating a layer of raw material with a melting point higher than that of the particles on the surface of the prepared particles or the raw material which can react with glass to generate a substance with a melting point higher than that of the particles; or mixing the prepared particles with raw materials with a melting point higher than that of the particles or mixing the prepared particles with raw materials which can react with glass to generate substances with a melting point higher than that of the particles; and drying the obtained substance or directly feeding the substance into a kiln for calcination, wherein the interior of the particles is foamed in the calcination process to form the expanded porous glass particles. In order to reduce the aperture ratio and the water absorption rate, the surface of the prepared particles needs to be coated with a layer of raw material with a melting point higher than that of the particles or a layer of raw material capable of reacting with glass to generate a substance with a melting point higher than that of the particles.
Disclosure of Invention
In view of the above analysis, the invention aims to provide a heat-insulating fireproof plate and a preparation method and application thereof, and solves the problems that a perlite heat-insulating plate in the prior art is fragile and easy to absorb water or a foamed glass heat-insulating plate is complex in preparation process and high in cost.
The invention is mainly realized by the following technical scheme:
the invention provides a heat-preservation, heat-insulation and fireproof plate which comprises the following components in parts by weight: 50-100 parts of foamed glass particles, 50-80 parts of cement, 6-8 parts of adhesive and 30-60 parts of water; the preparation raw materials of the foamed glass particles comprise the following components in parts by mass: 1000 parts of glass powder, 300-500 parts of water glass and 5-8 parts of urea, wherein the foamed glass particles are of a composite structure and comprise porous balls and glass shells wrapping the porous balls.
Further, the preparation raw materials also comprise the following components in parts by mass: 60-120 parts of an anti-sticking agent, wherein the anti-sticking agent wraps the glass shell.
Further, the anti-sticking agent is white carbon black, black carbon black or graphite powder.
Further, the anti-blocking agent is black carbon black.
Further, the glass powder is glass dust generated in the process of preparing the glass powder by crushing waste glass.
The invention also provides a preparation method of the heat-preservation heat-insulation fireproof plate, which comprises the following steps:
step A: mixing the foamed glass particles, cement, an adhesive and water to obtain a mixture;
and B, step B: and (4) making and curing the mixture to obtain the heat-insulating fireproof plate.
Further, the step a comprises the following steps:
step I: mixing cement, an adhesive and water to obtain an adhesive material;
step II: and adding the foamed glass particles into the bonding material to obtain a mixture.
Further, the preparation of the foamed glass particles comprises the following steps:
step 1: mixing urea, water glass and glass powder to obtain mixed particles;
step 2: drying the mixed particles;
and step 3: screening and grading the dried mixed particles to obtain mixed particles with the particle size within a threshold range;
and 4, step 4: and firing and foaming the mixed particles with the particle size within the threshold range to obtain the foamed glass particles.
Further, the threshold range is 0.5-3 mm.
Further, the step 1 includes the following steps:
step 11: mixing urea and water glass to obtain a mixture;
step 12: and spraying the mixture into glass powder by adopting a high-pressure spraying mode, and stirring and mixing to obtain mixed particles.
Further, in the step 12, the rotation speed of stirring is 0.3 to 1rad/s, the pressure of high-pressure spraying is 1500 to 5000pa, and the adding time of the mixture is 5 to 10 min.
Further, the pressure of the high-pressure spraying is 2000-4000 pa.
Further, in step 12, the rotation speed of the stirring is gradually increased, and the pressure of the high-pressure spray is gradually decreased.
Furthermore, the particle size of the mixed particles is controlled to be 0.5-3 mm.
Further, the step 2 includes the following steps:
step 21: spreading the mixed particles, and naturally airing;
step 22: and drying the dried mixed particles.
Further, the method comprises the following steps after the tiling and before the natural airing:
removing the mixed particles with the particle size of more than 15mm, crushing the mixed particles with the particle size of more than 15mm, and mixing the crushed mixed particles into the mixed particles again.
Further, in the step 21, the airing time is 6-24 hours.
Further, in the step 22, the drying temperature is 350-500 ℃, and the drying time is 5-10 min.
Further, after screening and grading, crushing the mixed particles of which the particle size is larger than the threshold range, mixing the crushed mixed particles with the dried mixed particles obtained in the step 2, and then screening and grading again.
Further, after the sieving and classification, the mixed particles having a particle size smaller than the threshold range are returned to step 1 as glass frit.
Further, a discharge hole of the vibrating screen for screening and grading is provided with a magnet.
Further, in the step 4, the temperature for firing and foaming is 805-850 ℃, and the time for firing and foaming is 3-15 min.
Further, the following steps are also included between the step 3 and the step 4:
and uniformly stirring the anti-sticking agent and the mixed particles with the particle size within the threshold range.
Furthermore, the stirring speed is 0.3 to 1rad/s, and the stirring time is 3 to 5 min.
Further, in the step 4, after firing and foaming the mixed particles having the particle size within the threshold range, the method further includes the following steps: separating the fired and foamed mixed particles, and removing the anti-sticking agent in the mixed particles.
The invention also provides application of the heat-insulating fireproof plate, which can be used for a heat-insulating fireproof layer of an external wall of a building or an indoor partition plate of the building.
Compared with the prior art, the invention can realize at least one of the following beneficial effects:
a) according to the heat-insulation fireproof plate provided by the invention, urea is used as a foaming agent, the outer layer of raw material particles is heated firstly, glass powder is melted to form a compact glass-state glass shell with a continuous closed structure, then, a raw material mixture positioned in the glass shell is foamed to form a porous ball under the action of the urea, namely, the glass shell wrapping the porous ball is formed on the surface of the porous ball when the porous ball is formed in the foaming process of the glass powder, so that a structure similar to a steamed bun is obtained. Due to the existence of the glass shell, the hardness of the foamed glass particles can be increased, the high-temperature resistance is improved, water can be prevented from entering the porous ball, and therefore the aperture ratio and the water absorption rate of the foamed glass particles can be effectively reduced.
b) In the heat-insulating fireproof plate provided by the invention, the porous ball is of a porous structure, so that the porous structure not only has the heat-insulating effect, but also can effectively reduce the quality of the foamed glass particles.
c) In the heat-insulating fireproof plate provided by the invention, the water glass is used as a solvent and a nucleating agent, so that particles of glass powder can be adhered to each other, and granulation is facilitated.
d) In the heat-insulating fireproof plate provided by the invention, the glass powder just utilizes secondary waste (glass dust) generated in the process of recycling waste (waste glass) as a raw material, the raw material price is quite low, and the problem of processing the glass dust which troubles glass factories for a long time can be effectively solved by utilizing the glass dust. In addition, compared with the method of preparing the foamed glass particles by using waste glass as a raw material and glass dust as a raw material, the method can omit the step of crushing, effectively simplify the process of preparing the foamed glass particles and is more suitable for industrial production.
e) The preparation method of the heat-preservation, heat-insulation and fire-proof plate provided by the invention immediately carries out screening and grading after drying, and at the moment, the mixed particles are not fired and foamed, so that the mixed particles with larger or smaller particle size after screening and grading can be further recycled.
f) According to the preparation method of the heat-preservation heat-insulation fireproof plate, the urea and the water glass are mixed, and the powdered urea can be dissolved in the liquid water glass in advance, so that the urea and the water glass can be uniformly mixed; in addition, urea is used as a foaming agent, the mixing uniformity of the urea and glass powder is particularly important for foaming reaction, the mixture of the urea and water glass is mixed with the glass powder, solid urea with small addition amount is pre-mixed with liquid water glass with large addition amount, and then the mixture is mixed with the glass powder, so that the urea and the glass powder can be fully and uniformly mixed, the uniformity of foaming reaction is ensured, and mixed particles with more uniform particle size can be obtained; in addition, the mixture is prepared into spray in a high-pressure spraying mode, compared with direct addition, the size of sprayed droplets is smaller, and the spray is sprayed into the glass powder, so that the urea and the glass powder can be further uniformly mixed.
g) According to the preparation method of the heat-preservation, heat-insulation and fireproof plate, a natural airing method abandoned in the drying field is adopted before drying, the water content of the surfaces of the mixed particles can be preliminarily reduced through airing, the mixed particles can be prevented from being bonded at the feeding port of a dryer in the subsequent drying and feeding process, the drying efficiency can be effectively improved, the drying time is shortened, energy is saved, and therefore the drying effect better than that of direct drying can be obtained.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.
Drawings
The drawings are only for purposes of illustrating the particular invention and are not to be construed as limiting the invention, wherein like reference numerals are used to designate like parts throughout the figures.
FIG. 1 is a schematic structural view of an insulation fire-proof plate according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of foamed glass particles in an insulating fire-proof plate according to an embodiment of the present invention;
FIG. 3 is a cross-sectional view of a single particle of foamed glass particles in an insulation fire-proof board according to an embodiment of the present invention;
fig. 4 is a diagram of a plurality of particles of foamed glass particles in an insulation fire-proof plate according to an embodiment of the present invention.
Reference numerals:
1-a porous ball; 2-a glass housing; 3-a binder; 4-foamed glass particles.
Detailed Description
The preferred invention will now be described in detail with reference to the accompanying drawings, which form a part hereof, and which together with the description serve to explain the principles of the invention.
The invention provides a heat-insulation fireproof plate, which comprises the following components in parts by weight as shown in figures 1 to 4: 450-100 parts of foamed glass particles, 50-80 parts of cement, 6-8 parts of adhesive and 30-60 parts of water; the preparation raw materials of the foamed glass particles 4 comprise the following components in parts by mass: 1000 parts of glass powder, 300-500 parts of water glass and 5-8 parts of urea, wherein the water glass is sodium silicate (Na) 2 SiO 3 ) An aqueous solution of (a). The foaming glass particles 4 are of a composite structure and comprise porous balls 1 and glass shells 2 wrapping the porous balls 1, wherein the glass shells 2 are continuously closed compact colored glaze-state shells, and the structure is similar to that of a 'steamed bun'.
Compared with the prior art, the foaming glass particles 4 in the heat-insulating fireproof plate provided by the invention adopt urea as a foaming agent, the outer layer of the raw material particles is heated firstly, the glass powder is melted to form the compact colored glaze shell 2 with a continuous closed structure, then, the raw material mixture in the glass shell is foamed to form the porous ball 1 under the action of the urea, namely, the glass shell 2 wrapping the porous ball 1 is formed on the surface of the porous ball 1 when the porous ball 1 is formed in the foaming process of the glass powder, so that the structure similar to steamed bread is obtained. Due to the existence of the glass shell 2, the hardness of the foamed glass particles 4 can be increased, the high temperature resistance is improved, water can be prevented from entering the porous ball 1, and therefore the aperture ratio and the water absorption rate of the foamed glass particles 4 can be effectively reduced. Meanwhile, the porous ball 1 is of a porous structure, so that the porous structure not only has the heat preservation and insulation effects, but also can effectively reduce the mass of the foamed glass particles 4, and further can improve the heat preservation, heat insulation and fire resistance of the heat preservation and insulation fire-proof plate.
In addition, the foam glass particles 4 in the heat-insulation fireproof plate provided by the invention adopt water glass as a solvent and a nucleating agent, and can adhere glass powder particles to each other, so that the granulation is facilitated.
In the preparation process, in order to prevent the foaming glass particles 4 from being bonded with each other and prevent the foaming glass particles 4 from being bonded with the firing furnace wall, the preparation raw materials further comprise the following components in parts by mass: 60-120 parts of an anti-sticking agent, and the glass shell 2 is wrapped by the anti-sticking agent 3. Thus, the anti-sticking agent 3 can isolate the adjacent two foamed glass particles 4 and the foamed glass particles 4 from the fired furnace wall, and prevent the glass envelope 2 from being stuck before the glass envelope is completely solidified.
Illustratively, the above-mentioned releasing agent 3 is white carbon black, black carbon black (common commercially available black carbon black) or graphite powder.
The anti-sticking agent 3 is black carbon black from the viewpoint of the preparation cost of the heat-insulating and fire-proof plate. The anti-sticking effect of the white carbon black, the graphite powder and the black carbon black is basically the same, and compared with the white carbon black and the graphite powder, the black carbon black is lower in price, so that the preparation cost of the heat-insulation fireproof plate can be effectively reduced.
In order to further reduce the manufacturing cost of the heat-insulating and fire-proof plate, the glass dust is generated in the process of crushing waste glass to prepare the glass dust, and it is noted that when a glass factory crushes the waste glass, a dust collector for collecting the glass dust is arranged to prevent the glass dust from polluting the environment, in the actual production, about 1 ton of glass dust is generated when 10 tons of waste glass are crushed, and the generation amount of the glass dust is very large. In addition, compared with the method of preparing the foamed glass particles 4 by using waste glass as a raw material and using glass dust as a raw material, the method can omit the step of crushing, effectively simplify the process of preparing the foamed glass particles 4, and is more suitable for industrial production.
The invention also provides a preparation method of the heat-preservation heat-insulation fireproof plate, which is used for preparing the heat-preservation heat-insulation fireproof plate and comprises the following steps:
step A: mixing the foamed glass particles, cement, an adhesive and water to obtain a mixture;
and B: and (4) making and curing the mixture to obtain the heat-insulating fireproof plate.
Compared with the prior art, the beneficial effects of the preparation method of the heat-preservation, heat-insulation and fireproof plate provided by the invention are basically the same as those of the heat-preservation, heat-insulation and fireproof plate, and are not repeated herein.
In order to ensure the mixing uniformity of the foamed glass particles, the cement, the adhesive and the water, the step A comprises the following steps:
step I: mixing cement, an adhesive and water to obtain an adhesive material;
step II: and adding the foamed glass particles into the bonding material to obtain a mixture.
The foaming glass particles, the cement, the adhesive and the water are mixed in the above mixing mode, and the cement, the adhesive and the water are mixed uniformly, so that the adhesive material with better adhesion is obtained; and then adding the foamed glass particles into the bonding material, so that the bonding material can uniformly wrap the foamed glass particles, and the strength of the prepared heat-insulating fireproof plate can be ensured.
As for the preparation of the foamed glass particles, specifically, the preparation of the foamed glass particles comprises the steps of:
step 1: mixing urea, water glass and glass powder to obtain mixed particles;
step 2: drying the mixed particles;
and step 3: screening and grading the dried mixed particles to obtain mixed particles with the particle size within a threshold range (for example, 0.5-3 mm);
and 4, step 4: and firing and foaming the mixed particles with the particle size within the threshold range to obtain the foamed glass particles.
In the prior art, the foamed glass particles are generally screened and classified after being fired and foamed, but because the raw materials are foamed and fired, the foamed glass particles with larger particles or smaller particles after being screened and classified cannot be recycled and can only be discarded; the preparation method of the foamed glass particles immediately performs screening and grading after drying, and at the moment, the mixed particles are not fired and foamed, so that the mixed particles with larger or smaller particle size after being screened and graded can be further recycled.
In order to facilitate the uniform mixing of the urea, the water glass and the glass powder, the step 1 comprises the following steps:
step 11: mixing urea and water glass to obtain a mixture;
step 12: and spraying the mixture into glass powder by adopting a high-pressure spraying mode, and stirring and mixing to obtain mixed particles.
This is because urea and water glass are mixed, and urea in powder form can be dissolved in water glass in liquid form in advance, so that urea and water glass can be uniformly mixed; in addition, urea is used as a foaming agent, the mixing uniformity of the urea and glass powder is particularly important for foaming reaction, the mixture of the urea and water glass is mixed with the glass powder, solid urea with small addition amount is pre-mixed with liquid water glass with large addition amount, and then the mixture is mixed with the glass powder, so that the urea and the glass powder can be fully and uniformly mixed, the uniformity of foaming reaction is ensured, and mixed particles with more uniform particle size can be obtained; in addition, the mixture is prepared into spray in a high-pressure spraying mode, compared with direct addition, the size of sprayed droplets is smaller, and the spray is sprayed into the glass powder, so that the urea and the glass powder can be further uniformly mixed.
In order to further improve the mixing uniformity of the urea, the water glass and the glass powder, in the step 12, the stirring speed is 0.3 to 1rad/s, the pressure of the high-pressure spraying is 1500 to 5000pa (2000 to 4000pa), and the adding time of the mixture (the time of the high-pressure spraying of the mixture) is 5 to 10 min.
It should be noted that the rotation speed of the stirring and the pressure of the high-pressure spraying directly affect the particle size and the uniformity of the particle size of the obtained mixed particles, and therefore, in the step 12, the rotation speed of the stirring is gradually increased, and the pressure of the high-pressure spraying is gradually decreased. The reason is that with the addition of the mixture of urea and water glass, the viscosity of the whole mixing system is increased, the proportion of mixed particles with larger particle size is increased, the influence of the viscosity and the increased particle size on mixing can be compensated by increasing the rotating speed, and the mixing uniformity is improved; meanwhile, with the addition of the mixture of urea and water glass, the proportion of glass powder which is not granulated in the mixing system is gradually reduced, the pressure of high-pressure spraying is reduced, namely the adding speed of the mixture of urea and water glass is reduced, so that the over-high content of urea in the mixed granules in the later stage of addition and the over-large particle size of the prepared foamed glass granules can be avoided, and the uniformity of the prepared mixed granules can be further improved.
In order to ensure that the particle size of the prepared foamed glass particles is in a proper range, the particle size of the mixed particles is controlled to be 0.5-3 mm. This is because the particle size of the mixed particles directly affects the particle size of the foamed glass particles, and controlling the particle size of the mixed particles within the above range can ensure that the particle size of the foamed glass particles produced at a later stage is within an appropriate range.
Considering that the mixed particles have a high viscosity and are adhered to the inlet of the dryer when directly dried, the step 2 includes the following steps:
step 21: spreading the mixed particles, and naturally airing;
step 22: and drying the dried mixed particles.
According to the drying method provided by the invention, a natural airing method abandoned in the drying field is adopted before drying, the water content on the surface of the mixed particles can be preliminarily reduced through airing, the mixed particles can be prevented from being bonded at the feeding port of the dryer in the subsequent drying and feeding process, the drying efficiency can be effectively improved, the drying time is shortened, the energy is saved, and the better drying effect than that of direct drying can be obtained.
In order to promote the natural airing efficiency, the method comprises the following steps after the tile is laid and before the natural airing:
removing the mixed particles with the particle size of more than 15mm, crushing the mixed particles with the particle size of more than 15mm, and mixing the crushed mixed particles into the mixed particles again, wherein the mixed particles have high water content and are easy to crush.
In order to ensure the effect of natural airing, in the step 21, the airing time is 6-24 hours, and sufficient natural airing time can ensure the effect of natural airing, so that the subsequent drying effect can be ensured.
Similarly, in order to ensure the drying effect, in the step 22, the drying temperature is 350 to 500 ℃, and the drying time is 5 to 10 min. Obviously, compared with the conventional drying temperature (720-1050 ℃) and drying time (20-90 min), the method combining natural drying and drying is adopted in the preparation process of the foamed glass particles, the moisture on the surfaces of the mixed particles is basically removed through natural drying before drying, and the temperature on the surfaces of the mixed particles can be properly increased, which is equivalent to preheating through drying, so that the drying temperature and the drying time can be effectively reduced.
In order to recycle the mixed particles with large particle size, after screening and classifying, crushing the mixed particles with the particle size larger than a threshold range (for example, 0.5 to 3mm), mixing the crushed mixed particles with the dried mixed particles obtained in the step 2, and then screening and classifying again. Similarly, in order to recycle the mixed particles having a small particle size, the mixed particles having a particle size smaller than a threshold range (for example, 0.5 to 3mm) are returned to step 1 as glass frit after being classified by sieving. By thus recycling the large-particle-size and mixed particles and the small-particle-size mixed particles, respectively, it is possible to achieve a sufficient use of raw materials (urea, water glass, and glass powder), and there is substantially no discharge of waste.
In order to avoid mixing in the hybrid particles to have metallic impurity to cause destruction to subsequent device, for example, rip the crushing screen cloth of breaker, the discharge gate of the shale shaker that above-mentioned screening is hierarchical adopts is equipped with the magnet, can get rid of the metallic impurity in the hybrid particles through the magnet to it has metallic impurity to cause destruction to subsequent device to avoid mixing in the hybrid particles.
In order to control the firing foaming speed and the expansion volume of the mixed particles, in the step 4, the firing foaming temperature is 805 to 850 ℃, and the firing foaming time is 3 to 15 min. The firing temperature and the firing time are controlled within the above ranges, and the volume expansion of the mixed particles is 2-4 times, so that the foamed glass particles with appropriate particle size can be obtained. In addition, in the preparation method, the moisture on the surface and in the mixed particles can be fully dried in a mode of combining natural airing and drying, the particle size of the mixed particles can be uniform through grading and screening, the mixed particles can be melted and foamed when the firing and foaming temperature is basically kept within the melting temperature range of the glass powder (the melting temperature of the glass powder is 810-825 ℃), and the required firing and foaming time is short and the energy consumption is low.
In the preparation process, in order to prevent the foaming glass particles from being bonded with each other and the foaming glass particles from being bonded with the firing furnace wall, the following steps are further included between the step 3 and the step 4:
and uniformly stirring the anti-sticking agent and the mixed particles with the particle size within the threshold range.
Thus, the anti-sticking agent and the mixed particles with the particle diameters within the threshold range are uniformly stirred, so that the anti-sticking agent can isolate two adjacent foamed glass particles and the foamed glass particles from the fired furnace wall, and the glass shell is prevented from being bonded before being incompletely solidified.
In order to ensure that the surface of the mixed particles with the particle size within the threshold value range can be coated with the anti-sticking agent, the stirring speed is 0.3-1 rad/s, and the stirring time is 3-5 min.
It is understood that the addition of the anti-sticking agent is to prevent the foamed glass particles from sticking during the preparation process, and the addition of the anti-sticking agent has a certain adverse effect on the properties of the final product of the foamed glass particles, so that the firing foaming of the mixed particles having the particle size in the threshold range in the above step 4 further comprises the steps of: separating the fired and foamed mixed particles, and removing the anti-sticking agent in the mixed particles.
The invention also provides application of the heat-insulating fireproof plate, which can be used for a heat-insulating fireproof layer of an external wall of a building or an indoor partition plate of the building.
Example one
The preparation method of the foamed glass particles provided by the embodiment comprises the following steps:
step a: mixing 5g of urea and 320g of water glass to obtain a mixture, wherein the particle size of the mixture is 2.5-2.8 mm;
step b: spraying the mixture into 1000g of glass powder in a high-pressure spraying manner, stirring and mixing at a stirring speed of 0.5rad/s and a high-pressure spraying pressure of 2000pa, wherein the adding time of the mixture is 6min, and obtaining mixed particles;
step c: flatly paving the mixed particles, removing the mixed particles with the particle size of more than 15mm, crushing the mixed particles with the particle size of more than 15mm, mixing the crushed mixed particles with the mixed particles again, and naturally airing for 20 hours;
step d: drying the aired mixed particles at the drying temperature of 500 ℃ for 8 min;
step e: screening and grading the dried mixed particles, and dividing the mixed particles into mixed particles with the particle size of more than 3mm, mixed particles with the particle size of 0.5-3 mm and mixed particles with the particle size of less than 0.5 mm;
d, crushing the mixed particles with the particle size larger than 3mm, mixing the crushed mixed particles with the dried mixed particles obtained in the step d, and sieving and grading again;
returning the mixed particles with the particle size smaller than the threshold range of 0.5mm to the step a to be used as glass powder;
step f: uniformly stirring 100g of black carbon black and mixed particles with the particle size within the threshold range, wherein the stirring speed is 0.5rad/s, and the stirring time is 5 min;
step g: and firing and foaming the mixed particles with the particle size of 0.5-3 mm at 845 ℃ for 10min, separating the fired and foamed mixed particles, and removing black carbon black in the mixed particles to obtain the foamed glass particles.
The foamed glass particles of the present example were tested to find that they had a thermal conductivity of 0.05 W.m -1 ·K -1 The compressive strength was 9.1 MPa.
Example two
The preparation method of the foamed glass particles provided by the embodiment comprises the following steps:
step a: mixing 8g of urea and 450g of water glass to obtain a mixture, wherein the particle size of the mixture is 2.5-2.8 mm;
step b: spraying the mixture into 1000g of glass powder by high-pressure spraying at a stirring speed of 1.0rad/s and a high-pressure spraying pressure of 3000pa, wherein the adding time of the mixture is 10min, and obtaining mixed particles;
step c: flatly paving the mixed particles, removing the mixed particles with the particle size of more than 15mm, crushing the mixed particles with the particle size of more than 15mm, mixing the crushed mixed particles with the mixed particles again, and naturally airing for 10 hours;
step d: drying the aired mixed particles at 350 ℃ for 5 min;
step e: screening and grading the dried mixed particles, and dividing the mixed particles into mixed particles with the particle size of more than 3mm, mixed particles with the particle size of 0.5-3 mm and mixed particles with the particle size of less than 0.5 mm;
d, crushing the mixed particles with the particle size larger than 3mm, mixing the crushed mixed particles with the dried mixed particles obtained in the step d, and sieving and grading again;
returning the mixed particles with the particle size smaller than the threshold range of 0.5mm to the step a to be used as glass powder;
step f: uniformly stirring 120g of black carbon black and the mixed particles with the particle size within the threshold range, wherein the stirring speed is 0.3rad/s, and the stirring time is 3 min;
step g: firing and foaming the mixed particles with the particle size of 0.5-3 mm at 830 ℃ for 9min, separating the fired and foamed mixed particles, and removing black carbon black in the mixed particles to obtain the foamed glass particles.
The foamed glass particles of the present example were tested to have a thermal conductivity of 0.048 W.m -1 ·K -1 The compressive strength is 9.3 MPa.
EXAMPLE III
The preparation method of the foamed glass particles provided by the embodiment comprises the following steps:
step a: mixing 6g of urea and 300g of water glass to obtain a mixture, wherein the particle size of the mixture is 2.5-2.8 mm;
step b: spraying the mixture into 1000g of glass powder by high-pressure spraying at a stirring speed of 0.9rad/s and a high-pressure spraying pressure of 5000pa for 5min to obtain mixed particles;
step c: flatly paving the mixed particles, removing the mixed particles with the particle size of more than 15mm, crushing the mixed particles with the particle size of more than 15mm, mixing the crushed mixed particles with the mixed particles again, and naturally airing for 24 hours;
step d: drying the dried mixed particles at 450 ℃ for 6 min;
step e: screening and grading the dried mixed particles, and dividing the mixed particles into mixed particles with the particle size of more than 3mm, mixed particles with the particle size of 0.5-3 mm and mixed particles with the particle size of less than 0.5 mm;
d, crushing the mixed particles with the particle size larger than 3mm, mixing the crushed mixed particles with the dried mixed particles obtained in the step d, and sieving and grading again;
returning the mixed particles with the particle size smaller than the threshold range of 0.5mm to the step a to be used as glass powder;
step f: uniformly stirring 110g of black carbon black and mixed particles with the particle size within a threshold range, wherein the stirring speed is 0.4rad/s, and the stirring time is 4 min;
step g: firing and foaming the mixed particles with the particle size of 0.5-3 mm at 850 ℃ for 3min, separating the fired and foamed mixed particles, and removing black carbon black in the mixed particles to obtain the foamed glass particles.
The foamed glass particles of the present example were tested to have a thermal conductivity of 0.045 W.m -1 ·K -1 The compressive strength is 9.0 MPa.
Example four
The preparation method of the foamed glass particles provided by the embodiment comprises the following steps:
step a: mixing 7g of urea and 500g of water glass to obtain a mixture, wherein the particle size of the mixture is 2.5-2.8 mm;
step b: spraying the mixture into 1000g of glass powder in a high-pressure spraying manner, stirring and mixing at a stirring speed of 0.3rad/s and a high-pressure spraying pressure of 1500pa, wherein the adding time of the mixture is 7min, and obtaining mixed particles;
step c: flatly paving the mixed particles, removing the mixed particles with the particle size of more than 15mm, crushing the mixed particles with the particle size of more than 15mm, mixing the crushed mixed particles with the mixed particles again, and naturally airing for 6 hours;
step d: drying the dried mixed particles at 480 ℃ for 10 min;
step e: screening and grading the dried mixed particles, and dividing the mixed particles into mixed particles with the particle size of more than 3mm, mixed particles with the particle size of 0.5-3 mm and mixed particles with the particle size of less than 0.5 mm;
d, crushing the mixed particles with the particle size larger than 3mm, mixing the crushed mixed particles with the dried mixed particles obtained in the step d, and sieving and grading again;
returning the mixed particles with the particle size smaller than the threshold range of 0.5mm to the step a to be used as glass powder;
step f: uniformly stirring 60g of black carbon black and the mixed particles with the particle size within the threshold range, wherein the stirring speed is 1.0rad/s, and the stirring time is 5 min;
step g: and firing and foaming the mixed particles with the particle size of 0.5-3 mm at the temperature of 805 ℃ for 15min, separating the fired and foamed mixed particles, and removing black carbon black in the mixed particles to obtain the foamed glass particles.
The foamed glass particles of the present example were tested to have a thermal conductivity of 0.044 W.m -1 ·K -1 The compressive strength is 9.7 MPa.
EXAMPLE five
The preparation method of the heat-preservation, heat-insulation and fire-proof plate provided by the embodiment adopts the foamed glass particles prepared in the first embodiment, and the preparation method comprises the following steps:
step A: mixing 56 parts of cement, 7 parts of adhesive and 55 parts of water to obtain an adhesive material; adding 60 parts of foamed glass particles into the bonding material to obtain a mixture;
and B: and (4) making and curing the mixture to obtain the heat-insulating fireproof plate.
The heat-insulating fireproof board is tested, and the heat conductivity coefficient is 0.048 W.m -1 ·K -1 The compressive strength was 10.5 MPa.
EXAMPLE five
The preparation method of the heat-preservation, heat-insulation and fire-proof plate provided by the embodiment adopts the foamed glass particles prepared in the first embodiment, and the preparation method comprises the following steps:
step A: mixing 56 parts of cement, 7 parts of adhesive and 55 parts of water to obtain an adhesive material; adding 60 parts of foamed glass particles into the bonding material to obtain a mixture;
and B, step B: and (4) making and curing the mixture to obtain the heat-insulation fireproof plate.
The heat-insulating fireproof board is tested to obtain the heat conductivity coefficient of 0.051 W.m -1 ·K -1 The compressive strength is 10.2 MPa.
EXAMPLE six
The preparation method of the heat-preservation, heat-insulation and fire-proof plate provided by the embodiment adopts the foamed glass particles prepared in the second embodiment, and the preparation method comprises the following steps:
step A: mixing 95 parts of cement, 8 parts of adhesive and 78 parts of water to obtain an adhesive material; adding 100 parts of foamed glass particles into the bonding material to obtain a mixture;
and B, step B: and (4) making and curing the mixture to obtain the heat-insulating fireproof plate.
The heat-insulating fireproof board is tested, and the heat conductivity coefficient is 0.05 W.m -1 ·K -1 The compressive strength is 10.5 MPa.
EXAMPLE seven
The preparation method of the heat-preservation, heat-insulation and fire-proof plate provided by the embodiment adopts the foamed glass particles prepared in the first embodiment, and the preparation method comprises the following steps:
step A: mixing 80 parts of cement, 6 parts of adhesive and 75 parts of water to obtain an adhesive material; adding 30 parts of foamed glass particles into the bonding material to obtain a mixture;
and B: and (4) making and curing the mixture to obtain the heat-insulation fireproof plate.
The heat-insulating fireproof plate is tested to obtain the heat conductivity coefficient of 0.052 W.m -1 ·K -1 The compressive strength is 10.6 MPa.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Claims (8)

1. The heat-preservation and heat-insulation fireproof plate is characterized by comprising the following components in parts by mass: 50-100 parts of foamed glass particles, 50-80 parts of cement, 6-8 parts of adhesive and 30-60 parts of water;
the preparation raw materials of the foaming glass particles comprise the following components in parts by mass: 1000 parts of glass powder, 300-500 parts of water glass and 5-8 parts of urea, wherein the foamed glass particles comprise porous balls and glass shells wrapping the porous balls;
the glass powder is glass dust generated in the process of preparing the glass powder by crushing waste glass;
the preparation method of the heat-preservation heat-insulation fireproof plate comprises the following steps:
step A: mixing the foamed glass particles, cement, an adhesive and water to obtain a mixture;
and B: the mixture is subjected to plate making and curing to obtain a heat-insulation fireproof plate;
the preparation of the foamed glass particles comprises the following steps:
step 1: mixing urea and water glass to obtain a mixture; spraying the mixture into glass powder in a high-pressure spraying manner, and stirring and mixing to obtain mixed particles;
step 2: drying the mixed particles;
and step 3: screening and grading the dried mixed particles to obtain mixed particles with the particle size within a threshold range;
and 4, step 4: firing and foaming the mixed particles with the particle size within the threshold range to obtain foamed glass particles;
after screening and grading, crushing the mixed particles of which the particle size is larger than the threshold range, mixing the crushed mixed particles with the dried mixed particles obtained in the step (2), and screening and grading again;
after the screening and grading, returning the mixed particles with the particle size smaller than the threshold range to the step 1 to be used as glass powder;
the threshold range is 0.5-3 mm.
2. The heat-insulating fireproof plate according to claim 1, wherein the raw materials for preparing the foamed glass particles further comprise, in parts by mass: 60-120 parts of an anti-sticking agent, wherein the anti-sticking agent wraps the glass shell.
3. A method for producing an insulating and fire-proof plate according to claim 1 or 2, wherein the method comprises the steps of:
step A: mixing the foamed glass particles, cement, an adhesive and water to obtain a mixture;
and B, step B: and (4) making and curing the mixture to obtain the heat-insulating fireproof plate.
4. The method for preparing the heat-insulating and fire-preventing plate according to claim 3, wherein the step A comprises the following steps:
step I: mixing cement, an adhesive and water to obtain an adhesive material;
step II: and adding the foamed glass particles into the bonding material to obtain a mixture.
5. The method for preparing the heat-insulating and fire-preventing plate according to claim 4, wherein the step 1 comprises the following steps:
step 11: mixing urea and water glass to obtain a mixture;
step 12: and spraying the mixture into glass powder in a spraying manner, and stirring and mixing to obtain mixed particles.
6. The method for preparing a heat-insulating and fire-preventing board according to claim 5, wherein the rotation speed of the stirring is gradually increased and the pressure of the spray is gradually reduced.
7. The preparation method of the heat-insulating fireproof plate according to claim 4, wherein in the step 3, a discharge port of a vibrating screen for screening and grading is provided with a magnet.
8. The application of the heat-preservation, heat-insulation and fire-prevention plate is characterized in that the heat-preservation, heat-insulation and fire-prevention plate is used for a heat-preservation, heat-insulation and fire-prevention layer of an external wall of a building or an indoor partition plate of the building; the heat-insulating fireproof plate is the heat-insulating fireproof plate according to claim 1 or 2.
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