Amorphous zirconia corundum refractory brick and preparation method thereof

Abstract

The invention relates to the technical field of amorphous zirconia corundum bricks, in particular to an amorphous zirconia corundum refractory brick and a preparation method thereof.The amorphous zirconia corundum refractory brick comprises, by weight, 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives and 11-13 parts of binder.The preparation method comprises the steps of mixing, pouring, drying in the shade and baking. The components of the amorphous zirconia corundum refractory brick are adjusted, silica sol is added as a binder, and one or more of a binder additive, a water reducer additive and a dispersant additive is / are selected as an additive, so that alumina powder and zircon sand are dispersed more uniformly and combined more tightly; and in the preparation process, the green bricks are heated and baked by utilizing a transformed and innovated trolley furnace, the heating is uniform, and the formed amorphous zirconia corundum refractory brick is compact in structure, high-temperature-resistant, corrosion-resistant and permeation-resistant.

Description

Technical Field

[0001] The invention relates to the technical field of amorphous zirconium corundum bricks, and in particular to an amorphous zirconium corundum refractory brick and a preparation method thereof. Background Art

[0002] Amorphous zirconium corundum bricks are a kind of refractory material made of industrial alumina powder and zircon sand as the main raw materials. The raw materials are melted at high temperature, and an appropriate amount of flux is added. Then, casting, ramming and other construction methods are adopted to form a refractory structure of specific shape and size at the site of use to meet the lining requirements of different industrial kilns and other thermal equipment.

[0003] Amorphous zirconium corundum bricks have no fixed shape. They are in loose or muddy form before construction. They can be flexibly constructed and manufactured on site according to the specific shape and size requirements of the use site. They can better adapt to complex kiln structures and shapes, such as some irregular corners, special connection parts, etc.

[0004] Moreover, since amorphous zirconium corundum bricks can be customized according to specific use environments and requirements, they may have better performance in some special parts or places with high requirements for sealing and integrity. For example, by adjusting the formula and construction process, they can have better corrosion resistance in certain specific corrosive media, or have better thermal stability and volume stability at high temperatures. However, if the construction is improper, it may affect its performance.

[0005] For example, a Chinese patent with patent application number CN202220174655.0 discloses a connection structure between the hearth and the bottom of a blast furnace, in which the hearth and the bottom are integrally cast and formed using amorphous refractory materials, and a rounded transition is used between the hearth and the bottom; the outer side of the casting layer of amorphous refractory material is a refractory brick masonry, wherein the area between the outer side of the hearth and the steel armor of the furnace shell is furnace wall refractory bricks, the lower part of the furnace bottom is furnace bottom refractory bricks, and the outer side of the connection between the hearth and the bottom is transition refractory bricks; the transition refractory bricks are multi-layer stepped refractory bricks matched with transition fillets.

[0006] However, the above-mentioned amorphous refractory bricks do not provide any preparation process, and the existing amorphous zirconium corundum bricks have problems such as uneven distribution of alumina powder and zircon sand during casting due to the selection of binder, and unstable heat during baking of the amorphous zirconium corundum bricks. Summary of the invention

[0007] In view of the above problems, the present invention provides an amorphous zirconium corundum refractory brick and a preparation method thereof. The components of the amorphous zirconium corundum refractory brick are adjusted, silica sol is added as a binder, and one or more of a binder additive, a water reducer additive, and a dispersant additive are selected as additives, so that the alumina powder and the zircon sand are dispersed more evenly and combined more tightly. In the preparation process, the brick blanks are heated and baked in an innovative trolley furnace, and the heat is evenly applied. The amorphous zirconium corundum refractory bricks formed have a dense structure and are resistant to high temperature, corrosion, and penetration.

[0008] To achieve the above object, the present invention provides the following technical solutions: An amorphous zirconium corundum refractory brick comprises, by weight: 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives, 11-13 parts of binder; The alumina powder has a particle size of 1-1.5 mm and a purity of >99%. The zircon sand contains 65% zirconium oxide and 34% silicon dioxide, and has a particle size of 0.05-2 mm. The additive is one or more of a binder additive, a water reducer additive, and a dispersant additive. The binder is silica sol, and the silica sol has a silicon dioxide content of 30%.

[0009] The binder additive is preferably phosphoric acid and phosphate or aluminate cement; phosphoric acid and phosphate can react with the components such as alumina in zirconium corundum to form a binding phase with high strength and high temperature stability, so that the refractory bricks maintain good structural integrity at high temperatures. For example, aluminum dihydrogen phosphate as a binder will undergo a polymerization reaction during the heating process to form a network structure, which firmly bonds the zirconium corundum particles together.

[0010] Aluminate cement can provide early strength, so that refractory bricks can be hardened and formed quickly at room temperature, which is convenient for construction and use. At the same time, aluminate cement can also react with zirconium corundum and other raw materials at high temperatures to further improve the high-temperature performance of refractory bricks.

[0011] The surface of the silica particles in the silica sol contains a large number of hydroxyl groups (-OH). During the drying or sintering process, these hydroxyl groups will undergo condensation reactions with the hydroxyl groups on the surface of the zirconium corundum particles to form siloxane bonds (-Si-O-Si-), thereby building a strong chemical bond network between the zirconium corundum particles, tightly combining the particles together, greatly improving the bonding strength of the brick body, and silica sol has good fluidity and permeability, which can fully fill the tiny pores and gaps between the zirconium corundum particles. When the water in the silica sol evaporates, the silica particles will form gel in the pores, increasing the contact area and friction between the particles, enhancing the adhesion between the particles, and thus improving the overall strength of the brick body.

[0012] The water reducing agent additive is preferably sodium tripolyphosphate or calcium lignin sulfonate; sodium tripolyphosphate can reduce the water consumption of the refractory mixture. Under the premise of not changing the fluidity, reducing the amount of water helps to improve the strength and density of the refractory bricks. Because after the water consumption is reduced, the porosity is reduced and the structure of the material is more compact.

[0013] Calcium lignin sulfonate can be adsorbed on the surface of cement particles to form a protective film to prevent cement particles from agglomerating, thereby improving the fluidity of cement slurry and making refractory materials easier to construct and operate. It is also beneficial to improve the uniformity and strength of the material.

[0014] The dispersant additive is preferably sodium hexametaphosphate, which can better disperse the zirconium corundum particles in the liquid medium, prevent the particles from agglomerating, and improve the fluidity and uniformity of the mud. In the process of preparing refractory bricks, good dispersibility helps to fully mix the raw materials, making the performance of the products more stable and consistent.

[0015] As an improvement, the amorphous zirconium corundum refractory brick includes 65 parts of alumina powder, 30 parts of zircon sand, 5 parts of additives and 12 parts of binder.

[0016] As an improvement, the amorphous zirconium corundum refractory brick is arranged in a U shape, and the two side walls of the U shape of the amorphous zirconium corundum refractory brick are provided with notches.

[0017] In addition, the present invention also provides a method for preparing the amorphous zirconium corundum refractory bricks as described in the above claims, comprising the following steps: Step S1, mixing: according to the proportion, 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives and 11-13 parts of binder are added into a mixer and mixed and stirred evenly to form a casting material; Step S2, pouring, pouring the casting material prepared in step S1 into a prefabricated mold, and vibrating the mold to discharge gas in the casting material; Step S3, drying in the shade, transferring the mold in step S2 to a cool place for shade drying, so that the castable in the mold gradually dries and hardens to form a brick; Step S4, baking, removing the mold in step S3, transferring the brick to a trolley furnace for baking and drying, and the specific baking steps are as follows: Step T1, loading, transferring the bricks in step S3 to the trolley of the trolley furnace and placing them horizontally; Step T2, sealing the furnace, the trolley moves horizontally, and the bricks loaded thereon are transferred into the trolley furnace, and the furnace door of the trolley furnace is closed, so that the bricks are located in the sealed trolley furnace; Step T3, heating, the blast device and the gas delivery device on the trolley furnace are started respectively, the blast device delivers the air outside the trolley furnace to the natural gas burned on the gas delivery device for heating, and then the hot air flow is input into the closed furnace chamber of the trolley furnace to heat the bricks, and the temperature is heated to 500-600°C, the heating rate is controlled at 25°C-35°C / h, and the heating time is 15-20h; Step T4, output, the brick blanks after baking are formed into amorphous zirconium corundum refractory bricks and output from the trolley furnace.

[0018] As an improvement, in step S3, when the trolley furnace heats the bricks, the support bars provided on the trolley plate on the top of the trolley are lifted so that the bricks are separated from the trolley plate and suspended in the air, and hot air flows under the bricks to bake and heat the bottom of the bricks.

[0019] As an improvement, in step S3, each group of bricks is covered with at least 5 groups of support bars, which are evenly distributed on both sides of the bottom of the bricks, and along the distribution direction of the support bars, the support bars in odd-numbered sequence and the support bars in even-numbered sequence are alternately raised and lowered to support the bricks.

[0020] As an improvement, in step S3, when the support bar is lifted to support the brick blank, a hot air flow is ejected from the side wall of the support bar in the length direction to heat and bake the bottom of the brick blank on both sides.

[0021] As an improvement, in step S3, when the support bar is lifted to support the brick blank, a cover plate is provided at the bottom of the support bar, a storage groove for accommodating the support bar is provided on the trolley plate, the cover plate covers the top of the storage groove to form an inflation cavity, and an air vent is provided on the side wall of the storage groove, so that the inflation cavity is connected to the natural gas combustion point on the gas transmission device through a pipeline, and the support rod arranged under the support bar is hollow, and an air inlet is provided on the support rod to connect the inflation cavity with the first spray hole on the upper side wall of the support bar.

[0022] As an improvement, in step S3, when the support bar descends to be out of contact with the brick blank and is stored in the storage groove, a hot air flow is ejected from the top of the support bar to heat and bake the bottom of the brick blank suspended above.

[0023] As an improvement, in step S3, when the support bar descends to break away from contact with the brick and is stored in the storage groove, the top edge of the support bar fits with the top opening of the storage groove to seal the top opening of the storage groove to form an inflation cavity, and an air supply hole is opened on the side wall in the width direction of the support bar, which connects the inflation cavity with the second spray hole at the top of the support bar.

[0024] The beneficial effects of the present invention are: (1) The present invention adjusts the components of amorphous zirconium corundum refractory bricks, adds silica sol as a binder, and selects one or more of binder additives, water reducer additives, and dispersant additives as additives. Silica sol can undergo condensation reaction through hydroxyl groups, greatly improving the bonding strength of the brick body. At the same time, the use of binder additives, water reducer additives, and dispersant additives makes the alumina powder and zircon sand more evenly dispersed and more tightly combined; (2) In the process of preparing amorphous zirconium corundum bricks, the present invention uses a modified and innovative trolley furnace to heat and bake the bricks, so that the bricks are suspended on the trolley, and the hot air flow can flow quickly under the bricks, so that the bricks can be heated evenly, and the amorphous zirconium corundum bricks formed have a dense structure, high temperature resistance, corrosion resistance, and penetration resistance; (3) The present invention arranges the support bars for supporting the brick blank in groups, so that the two groups of support bars alternately support the brick blank, thereby reducing the contact area between the bottom of the brick blank and the support bars. At the same time, the support bars act as hot air jet nozzles at the bottom, continuously ejecting hot air to bake the bottom of the brick blank, so that the brick blank is baked and dried evenly, and the heat quickly penetrates into the interior of the brick blank, ensuring the compact structure of the amorphous zirconium corundum brick; (4) The present invention adjusts the structure of the support bar supporting the brick blanks, utilizes the lifting action of the support bar, and cooperates with the cross-sectional shape of the support bar and the cover plate arranged at the bottom of the support bar, so that the storage groove on the trolley for accommodating the support bar can form an air-filled cavity when the support bar is lifted. When the support bar is lifted, the first spray hole on the side wall in the length direction of the support bar can spray hot air flow to heat and dry the bottom of the brick blanks on both sides of the support bar at a close distance. When the support bar is recovered, the support bar can heat the bottom of the top brick blank through the second spray hole arranged at the top. Therefore, regardless of the lifting setting of the support bar, the bottom of the brick blank can be well baked and dried. (5) The present invention enables the hot air flow from the first nozzle and the hot air flow from the second nozzle to be switched at will by means of the lifting arrangement of the support bar. At the same time, the lifting arrangement of the support bar can quickly switch the connection between the first nozzle and the second nozzle inflation chamber, thereby achieving the connection of the support bar to the baking and drying part at the bottom of the brick blank, so that the bottom of the brick blank can be completely baked and dried.

[0025] In summary, the present invention has the advantages of high quality, high forming rate, stable internal stress distribution, high temperature resistance, corrosion resistance, etc. of over-formed zirconium corundum refractory bricks, and is particularly suitable for the technical field of forming zirconium corundum refractory bricks. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an electron microscope magnified image of the internal structure of the amorphous zirconium corundum refractory brick; Figure 2 It is a schematic diagram of the preparation method of the present invention; Figure 3 The three-dimensional structure of the trolley furnace of the present invention is shown in FIG. Figure 1 ; Figure 4 The three-dimensional structure of the trolley furnace of the present invention is shown in FIG. Figure 2 ; Figure 5 This is a schematic diagram of the cross-sectional structure of the trolley furnace of the present invention in the length direction; Figure 6 It is a schematic diagram of the cross-sectional structure of the trolley furnace of the present invention in the width direction; Figure 7 for Figure 6 The enlarged structural diagram at A in the middle; Figure 8 This is a state diagram of the support bar when the trolley of the present invention initially carries the brick blank; Fig. 9 This is a state diagram of the trolley odd-numbered support bars supporting brick blanks of the present invention; Fig.10 for Fig. 9 Schematic diagram of the cross-section structure; Fig.11 for Fig.10 The enlarged structural diagram at B in the middle; Fig.12 for Fig.10 The enlarged structural diagram at C in the middle; Fig.13 for Fig.10 The enlarged structural diagram at D in the middle; Fig.14 This is a schematic diagram of the three-dimensional structure of the support bar of the present invention; Fig.15 It is a schematic diagram of the side view structure of the support bar of the present invention; Fig.16 This is a schematic diagram of the cross-sectional structure of the support bar of the present invention; Fig.17 This is a schematic diagram of the structure of the driving device of the present invention driving the support bar to rise and fall.

[0027] In the figure: trolley furnace I, trolley 1, brick 10, furnace door 11, pulley 111, rope 112, counterweight 113, rotating shaft 114, transmission chain unit 115, lifting motor 116, furnace chamber 12, trolley plate 13, inflation cavity 130, protrusion 131, groove 132, storage groove 133, vent 134, support bar 14, cover plate 141, support rod 142, air inlet 143, first spray hole 144, exhaust cavity 14 5, gas delivery hole 146, gas outlet cavity 147, top plate 148, second spray hole 149, track 15, roller 16, sprocket unit 17, motor 18, air hole 19, air blowing device 2, blower 21, air blowing pipeline 22, gas delivery device 3, gas bin 31, gas pump 32, gas pipeline 33, driving device 4, rotating swing arm 41, connecting rod 42, gear 43, rack 44, slide rail group 45, driving motor 46, combustion chamber 5. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] Example: An amorphous zirconium corundum refractory brick comprises, by weight: 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives, 11-13 parts of binder; The alumina powder has a particle size of 1-1.5 mm and a purity of >99%. The zircon sand contains 65% zirconium oxide and 34% silicon dioxide, and has a particle size of 0.05-2 mm. The additive is one or more of a binder additive, a water reducer additive, and a dispersant additive. The binder is silica sol, and the silica sol has a silicon dioxide content of 30%.

[0032] Preferably, the amorphous zirconium corundum refractory bricks include 65 parts of alumina powder, 30 parts of zircon sand, 5 parts of additives and 12 parts of binder.

[0033] In addition, the amorphous zirconium corundum refractory bricks of the present invention are arranged in a U shape, and the two side walls of the U shape of the amorphous zirconium corundum refractory bricks are provided with notches.

[0034] It should be noted that the main component of silica sol is silicon dioxide, and its melting point is as high as about 1600℃-1700℃, which is much higher than the temperature that amorphous zircon corundum bricks withstand during the baking and drying process. Therefore, in a high temperature environment, silica sol can maintain a stable chemical structure and physical properties, and will not soften, melt or decompose, thereby ensuring the stability of the bonding structure of amorphous zircon corundum bricks and amorphous zircon corundum bricks, as well as the high temperature stability of amorphous zircon corundum bricks.

[0035] In addition, silica sol forms a continuous and dense silicon dioxide protective film on the surface of zirconium corundum bricks. This protective film can effectively prevent external corrosive media (such as acidic gas, alkaline solution, slag, etc.) from contacting the zirconium corundum particles inside the brick body, thereby reducing the erosion rate of the brick body by the corrosive media and extending the service life of the brick body.

[0036] In addition, silica sol itself has good chemical stability and is not easy to react with acid, alkali and other chemical substances. Therefore, adding silica sol as a binder can improve the overall chemical stability of amorphous zirconium corundum bricks, so that they can still maintain good performance in harsh chemical environments.

[0037] Furthermore, silica sol has a low viscosity, and when mixed with zirconium corundum particles, the mixture can have good fluidity and plasticity, which is convenient for construction operation. This makes it easier to make amorphous zirconium corundum bricks into various shapes and sizes to meet the use requirements of different engineering parts, such as the notch structure of the amorphous zirconium corundum refractory bricks in the present invention.

[0038] like Figure 1 As shown in the figure, silica sol can evenly disperse zirconium corundum particles in it, prevent particles from agglomerating, and ensure the uniformity of the internal structure of the brick. During the construction process, this uniform mixture can better fill the mold or construction site, improving the molding quality and dimensional accuracy of the brick.

[0039] Embodiment 1-embodiment 3: The contents of the components of the amorphous zirconium corundum refractory bricks in Examples 1 to 3 are shown in Table 1 below: Table 1 Comparative Example 1-Comparative Example 3: The contents of the components of the amorphous zirconium corundum refractory bricks in Comparative Examples 1 to 3 are shown in Table 2 below: Table 2 It should be noted that the binders used in Comparative Examples 1 to 3 of the present invention are binders other than silica sol, such as aluminum dihydrogen phosphate, calcium aluminate cement, polyphosphate, phenolic resin, furan resin, etc. The binders in Comparative Examples 1 to 3 of the present invention preferably use aluminum dihydrogen phosphate, because the properties of aluminum dihydrogen phosphate in amorphous zirconium corundum refractory bricks are most similar to those of silica sol.

[0040] Specifically, similar features are as follows: 1. Bonding properties: Silica sol improves bonding strength by forming a strong chemical bond network through siloxane bonds. Aluminum dihydrogen phosphate has strong chemical bonding strength. After being mixed with refractory aggregates, hardeners, etc. at room temperature, it forms high bonding strength at a constant temperature of 90-110℃ for 4-24 hours. After being dried at 350℃-500℃, it has high bending, compression and hydration resistance, and can tightly bond the particles of refractory materials together, so that the products have better integrity and strength.

[0041] 2. High temperature resistance: The main component of silica sol, silicon dioxide, has a melting point of about 1600℃-1700℃, and can promote the sintering reaction of zirconium corundum, improving the high temperature resistance and thermal shock resistance of the brick. Aluminum dihydrogen phosphate is also a high temperature adhesive, which has the characteristics of high temperature resistance, shock resistance, peeling resistance, and high temperature air flow erosion resistance. It can maintain good bonding performance in high temperature environment, making the refractory material not easily damaged during use.

[0042] 3. Anti-corrosion properties: Silica sol enhances the corrosion resistance of amorphous zirconium corundum bricks by forming a dense silicon dioxide protective film. Phosphate compounds and other substances formed by refractory materials bonded by aluminum dihydrogen phosphate at high temperatures can also form a protective film on the surface of the material, improving the material's corrosion resistance and resisting the erosion of chemical substances such as acids and alkalis.

[0043] 4. Improve construction characteristics: Silica sol has good fluidity and plasticity, can evenly disperse particles, and is easy to operate. Aluminum dihydrogen phosphate is easy to mix and shape, suitable for on-site construction, and when mixed with refractory aggregates, it can make the mixture have better working performance and is easy to make refractory products of various shapes and sizes.

[0044] Therefore, the comparison between the amorphous zirconium corundum refractory bricks formed by using aluminum dihydrogen phosphate as the binder in Comparative Examples 1-3 and the amorphous zirconium corundum refractory bricks formed by using silica sol as the binder in Examples 1-3 is the most accurate.

[0045] The performance of the amorphous zirconium corundum refractory bricks prepared in the above embodiments and comparative embodiments was tested, and the results are shown in Table 3.

[0046] The test methods for apparent porosity and bulk density are: GB / T2997-2015 "Test methods for bulk density, apparent porosity and true porosity of dense shaped refractory products". The test method for compressive strength is: GB / T5072-2008 "Test method for compressive strength of refractory materials at room temperature". The glass phase seepage and resistance to glass liquid erosion are tested according to JC / T805 and JC / T806 standards.

[0047] Table 3 Performance test results As shown in Table 3 above, by comparing Examples 1-3 with Comparative Examples 1-3, it can be seen that the amorphous zirconium corundum refractory bricks prepared by using silica sol as a binder are superior to those prepared by using aluminum dihydrogen phosphate as a binder in terms of apparent porosity, bulk density, compressive strength, glass corrosion resistance and glass phase seepage. Moreover, since silica sol can evenly disperse the zirconium corundum particles therein to prevent the particles from agglomerating, the glass corrosion resistance and glass phase seepage of the amorphous zirconium corundum refractory bricks prepared by Examples 1-3 are superior to those prepared by Comparative Examples 1-3.

[0048] Embodiment 4: like Figure 2 As shown, a method for preparing the amorphous zirconium corundum refractory bricks described in Examples 1 to 3 comprises the following steps: Step S1, mixing: according to the proportion, 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives and 11-13 parts of binder are added into a mixer and mixed and stirred evenly to form a casting material; Step S2, pouring, pouring the casting material prepared in step S1 into a prefabricated mold, and vibrating the mold to discharge gas in the casting material; Step S3, drying in the shade, transferring the mold in step S2 to a cool place for drying in the shade, so that the castable in the mold gradually dries and hardens to form a brick 10; Step S4, baking, the mold in step S3 is removed, and the brick 10 is transferred to the trolley furnace 1 for baking and drying. The specific baking steps are as follows: Step T1, loading, transferring the brick 10 in step S3 to the trolley 1 of the trolley furnace I and placing it horizontally; Step T2, sealing the furnace, the trolley 1 moves horizontally, and the brick blanks 10 loaded thereon are transferred into the trolley furnace I, and the furnace door 11 of the trolley furnace I is closed, so that the brick blanks 10 are located in the sealed trolley furnace I; Step T3, heating, the blast device 2 and the gas delivery device 3 on the trolley furnace 1 are started respectively, the blast device 2 delivers the air outside the trolley furnace 1 to the natural gas burned on the gas delivery device 3 for heating, and then the hot air flow is input into the closed furnace chamber 12 of the trolley furnace 1 to heat the brick 10, and the temperature is heated to 500-600°C, the heating rate is controlled at 25°C-35°C / h, and the heating time is 15-20h; Step T4, output, the brick blank 10 after baking is formed into an amorphous zirconium corundum refractory brick and output from the trolley furnace I.

[0049] Among them, in the step S3, when the trolley furnace I heats the brick blank 10, the support bar 14 arranged on the trolley plate 13 on the top of the trolley 1 is lifted, so that the brick blank 10 is separated from the trolley plate 13 and is suspended in the air, and a hot air flow flows under the brick blank 10 to heat the bottom of the brick blank 10.

[0050] Furthermore, in the step S3, each group of the brick blanks 10 is covered with at least 5 groups of support bars 14, and the support bars 14 are evenly distributed on both sides of the bottom of the brick blanks 10, and along the distribution direction of the support bars 14, the support bars 14 located in the odd sequence (such as 1, 3, 5...) and the support bars 14 located in the even sequence (such as 2, 4...) are alternately raised and lowered to support the brick blanks 10, thereby achieving rapid baking and drying of the bottom of the brick blanks 10. Compared with the original method of directly attaching the bottom of the brick blanks 10 to the trolley, which makes the baking and drying of the bottom of the brick blanks 10 slow, the baking and drying speed and uniformity of the present invention are greatly improved.

[0051] like Figures 3 to 17 As shown, it is specifically explained that the trolley furnace 1 of the present invention is heated by natural gas combustion, a track 15 is laid in the furnace chamber 12 of the trolley furnace 1, a roller 16 is provided at the bottom of the trolley 1, and the roller 16 moves along the track 15. The roller 16 at the front end of the bottom of the trolley 1 is connected to the roller 16 at the rear end through a sprocket unit 17, and the motor 18 drives all the rollers 16 to rotate and roll through the sprocket unit 17.

[0052] It is further explained that the furnace door 11 on the trolley furnace I is suspended at the feed port 101 of the trolley furnace I through a combination of a pulley 111, a rope 112 and a counterweight block 113, and a transmission chain unit 115 is arranged on the rotating shaft 114 of the pulley 111. The lifting motor 116 drives the pulley 111 to rotate through the transmission chain unit 115, and then the furnace door 11 is raised and lowered through the counterweight block 113.

[0053] It is further explained that a combustion chamber 5 is provided on the side wall of the trolley furnace I, and the air transported by the blast device 2 and the natural gas transported by the gas delivery device 3 converge in the combustion chamber 5. The air and natural gas are mixed and burned in the combustion chamber to form a high-temperature airflow which is input into the furnace chamber 12. The blast device 2 is composed of a blower 21 and a blast pipe 22. The blower 21 is connected to the combustion chamber 5 through the blast pipe 22. The gas delivery device 3 is composed of a gas bin 31, a gas pump 32 and a gas pipe 33. The gas bin 31 is connected to an external gas supply pipe. The gas pump 32 pumps natural gas into the gas pipe 33, and the natural gas enters the combustion chamber 5 through the gas pipe 33, and is then ignited by the burner. The heat generated by the combustion of the natural gas forms a heat exchange with the air to heat the air. Finally, the hot air is input into the furnace chamber 12 through the air holes 19 opened on the side wall of the trolley furnace I to heat the bricks 10 on the trolley 1.

[0054] Furthermore, a plurality of groups of support bars 14 are equidistantly arranged in the length direction of the trolley 1. The support bars 14 are raised and lowered above the trolley plate 13, and a driving device 4 for driving the support bars 14 to be raised and lowered is provided inside the trolley plate 13. The driving device 4 includes a rotating swing arm 41, a connecting rod 42, a gear 43, a rack 44 and a slide rail group 45. The rotating swing arm 41 and the support bar 14 are arranged one by one, and the rotating swing arm 41 and the support bar 14 are hinged through the connecting rod 42. When the rotating swing arm 41 rotates and swings, the corresponding support bar 14 will be driven to rise and fall, and a gear 43 is correspondingly provided on the rotating axis of the rotating swing arm 41, and a rack 44 is provided below the gear 43. The rack 44 is moved through the slide rail group 45, and the rack 44 is moved by the driving motor 46 through the gear.

[0055] When the trolley 1 initially carries the brick blanks 10, the support bars 14 on the trolley plate 13 are all in a semi-raised state, and the support bars 14 are all at the same height. The brick blanks 10 are placed on the support bars 14, and then the trolley 1 moves into the furnace chamber 12 of the trolley furnace I. A protrusion 131 is protruded on the side wall in the length direction of the trolley plate 13, and a groove 132 is provided on the corresponding trolley furnace I. The trolley 1 cooperates between the protrusion 131 and the groove 132, so that the trolley plate 13 seals the bottom of the trolley furnace I, and then the support bars 14 in the odd sequence rise, and the support bars 14 in the even sequence fall (conversely, the support bars 14 in the odd sequence fall, and the support bars 14 in the even sequence rise, and this cycle is repeated), so that the brick blanks 10 are always in a suspended state, and the height of the brick blanks 10 fluctuates as the support bars 14 are switched, thereby accelerating the baking and drying speed at the bottom of the brick blanks 10.

[0056] The trolley plate 13 is provided with a receiving groove 133 for accommodating the support bar 14. When the support bar 14 is lowered, it will enter the receiving groove 133. A cover plate 141 is provided at the bottom of the support bar 14. When the support bar 14 is lifted to the highest point, the cover plate 141 covers the top opening of the receiving groove 133 to form an air-filled cavity 130. A vent hole 134 is provided on the side wall of the receiving groove 133. A delivery pipeline connected to the combustion chamber 5 is laid inside the side wall of the trolley furnace I. When the trolley plate 13 seals the bottom of the trolley furnace I, the vent hole 134 is just connected to the delivery pipeline. The inflation chamber 130 is connected with the combustion chamber 5, and the hot air flow is input into the combustion chamber 5. The support rod 142 arranged below the support bar 14 is hollow (the support rod 142 and the rotating swing arm 41 are hinged by the connecting rod 42), and an air inlet hole 143 is opened on the support rod 142. An exhaust chamber 145 is arranged in the side wall of the support bar 14, and a first spray hole 144 is opened on the side wall of the support bar 14. The hot air flow in the inflation chamber 130 enters into the exhaust chamber 145 through the air inlet hole 143, and is then discharged through the first spray hole 144.

[0057] In addition, the longitudinal section of the support bar 14 in the width direction is set in an inverted trapezoidal shape. When the support bar 14 is stored in the storage groove 133, the top of the support bar 14 just forms a contact seal with the top opening of the storage groove 133 (at this time, the cover plate 141 is located at the bottom of the storage groove 133, and the air inlet hole 143 on the support rod 142 is located outside the storage groove 133 and is not connected to the inflation chamber 130), forming the inflation chamber 130, and the side wall of the support bar 14 in the width direction is provided with an air transmission hole 146, and the center position of the support bar 14 is provided with an air outlet cavity 147, and the top of the air outlet cavity 147 (the air outlet cavity 147 and the exhaust cavity 145 are in a separated state and are not connected to each other) is the top plate 148 of the support bar 14, and the top plate 148 is provided with a second spray hole 149. The hot air from the inflation chamber 130 flows through the air transmission hole 146 into the air outlet cavity 147, and is then discharged through the second spray hole 149.

[0058] Specifically, when the support bar 14 is lifted to support the brick 10 , the first spray holes 144 on the side wall of the support bar 14 in the length direction spray hot air to heat and bake the bottom of the brick 10 on both sides of the support bar 14 .

[0059] When the support bar 14 is lowered to be out of contact with the brick blank 10 and stored in the storage groove 133, the second spray hole 149 on the top of the support bar 14 sprays hot air to heat and bake the bottom of the brick blank 10 suspended above.

[0060] By switching between the above two states, a continuous baking and drying effect is achieved at the bottom of the green brick 10 , thereby improving the drying quality of the bottom of the green brick 10 .

[0061] In addition, it should be noted that an exhaust pipe 300 is also provided on the trolley furnace I, and the exhaust pipe 300 is used to discharge the hot exhaust gas in the trolley furnace I. The exhaust pipe 300 can be connected with the gas supply device 3 so that the hot gas can be continuously circulated, thereby maintaining the air pressure in the trolley furnace I stable and reducing energy consumption.

[0062] In Table 3, the amorphous zirconium corundum refractory bricks prepared in Examples 1-3 were all baked and dried in the trolley furnace in Example 4 of the present invention. Now, referring to Examples 1-3, the prepared amorphous zirconium corundum refractory bricks were baked in a common trolley furnace, and then the formed amorphous zirconium corundum refractory bricks were tested to obtain the various parameters of Comparative Examples 4-6, as shown in Table 4 below: Table 4 As shown in Table 4 above, by comparing Examples 1-3 with Comparative Examples 4-6, it can be seen that various detection parameters of the amorphous zirconium corundum refractory bricks in Examples 1-3 after being dried by the trolley furnace of Example 4 are better than the amorphous zirconium corundum refractory bricks in Comparative Examples 4-6 after being dried by an ordinary trolley furnace. It can be seen that the trolley furnace of the present invention is far superior to the ordinary trolley furnace in terms of the baking and drying quality of the amorphous zirconium corundum refractory bricks, and can further improve the various performance parameters of the amorphous zirconium corundum refractory bricks.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An amorphous zirconium corundum refractory brick, characterized in that: In parts by weight: 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives, 11-13 parts of binder; The alumina powder has a particle size of 1-1.5 mm and a purity of >99%. The zircon sand contains 65% zirconium oxide and 34% silicon dioxide, and has a particle size of 0.05-2 mm. The additive is one or more of a binder additive, a water reducer additive, and a dispersant additive. The binder is silica sol, and the silica sol has a silicon dioxide content of 30%.

2. The amorphous zirconium corundum refractory brick according to claim 1, characterized in that: The amorphous zirconium corundum refractory brick comprises 65 parts of alumina powder, 30 parts of zircon sand, 5 parts of additives and 12 parts of binder.

3. The amorphous zirconium corundum refractory brick according to any one of claims 1 or 2, characterized in that: The amorphous zirconium corundum refractory brick is arranged in a U shape, and both side walls of the U shape of the amorphous zirconium corundum refractory brick are provided with notches.

4. A method for preparing the amorphous zirconium corundum refractory brick according to any one of claims 1 to 2, characterized in that: The following steps are involved: Step S1, mixing: according to the proportion, 60-70 parts of alumina powder, 25-35 parts of zircon sand, 5 parts of additives and 11-13 parts of binder are added into a mixer and mixed and stirred evenly to form a casting material; Step S2, pouring, pouring the casting material prepared in step S1 into a prefabricated mold, and vibrating the mold to discharge gas in the casting material; Step S3, drying in the shade, transferring the mold in step S2 to a cool place for shade drying, so that the castable in the mold gradually dries and hardens to form a brick; Step S4, baking, removing the mold in step S3, transferring the brick to a trolley furnace for baking and drying, and the specific baking steps are as follows: Step T1, loading, transferring the bricks in step S3 to the trolley of the trolley furnace and placing them horizontally; Step T2, sealing the furnace, the trolley moves horizontally, and the bricks loaded thereon are transferred into the trolley furnace, and the furnace door of the trolley furnace is closed, so that the bricks are located in the sealed trolley furnace; Step T3, heating, the blast device and the gas delivery device on the trolley furnace are started respectively, the blast device delivers the air outside the trolley furnace to the natural gas burned on the gas delivery device for heating, and then the hot air flow is input into the closed furnace chamber of the trolley furnace to heat the bricks, and the temperature is heated to 500-600°C, the heating rate is controlled at 25°C-35°C / h, and the heating time is 15-20h; Step T4, output, the brick blanks after baking are formed into amorphous zirconium corundum refractory bricks and output from the trolley furnace.

5. The method according to claim 4, characterized in that: In step S3, when the trolley furnace heats the bricks, the support bars provided on the trolley plate on the top of the trolley are lifted, so that the bricks are separated from the trolley plate and suspended in the air, and hot air flows under the bricks to bake and heat the bottom of the bricks.

6. The method according to claim 5, characterized in that: In step S3, each group of bricks is covered with at least 5 groups of support bars, which are evenly distributed on both sides of the bottom of the bricks, and along the distribution direction of the support bars, the support bars in odd numbers and the support bars in even numbers are alternately raised and lowered to support the bricks.

7. The method according to claim 5, characterized in that: In the step S3, when the support bar is lifted to support the brick, a hot air flow is sprayed from the side wall of the support bar in the length direction to heat and bake the bottom of the brick on both sides.

8. The method according to claim 7, characterized in that: In step S3, when the support bar is lifted to support the brick blank, a cover plate is provided at the bottom of the support bar, a storage groove for accommodating the support bar is provided on the trolley plate, the cover plate covers the top of the storage groove to form an air-filled cavity, and an air vent is provided on the side wall of the storage groove, so that the air-filled cavity is connected to the natural gas combustion point on the gas transmission device through a pipeline, and the support rod arranged below the support bar is hollow, and an air inlet is provided on the support rod to connect the air-filled cavity with the first spray hole on the upper side wall of the support bar.

9. The method according to claim 8, characterized in that: In step S3, when the support bar is lowered to be out of contact with the brick blank and stored in the storage groove, a hot air flow is ejected from the top of the support bar to heat and bake the bottom of the brick blank suspended above.

10. The method according to claim 9, characterized in that: In step S3, when the support bar descends to break away from the contact with the brick and is stored in the storage groove, the top edge of the support bar fits with the top opening of the storage groove to seal the top opening of the storage groove to form an inflation cavity, and an air supply hole is opened on the side wall of the support bar in the width direction, which connects the inflation cavity with the second spray hole on the top of the support bar.

Images