Preparation process of refractory material for high-temperature bauxite calcination rotary kiln

Abstract

The invention discloses a preparation process of a refractory material for a high-temperature bauxite calcination rotary kiln, and relates to the technical field of high-temperature-resistant materials. Magnesium aluminate spinel particles; alpha-alumina micro powder; tabular corundum fine powder; a binder; and water. The high-temperature bauxite calcination rotary kiln refractory material prepared by the invention takes tabular corundum particles, magnesium aluminate spinel particles, alpha-alumina micro powder and tabular corundum fine powder as main raw materials, high-calcium oxide / alumina porous pellets are prepared by adopting an in-situ decomposition method, and then the high-calcium oxide / alumina porous pellets are combined with an alumina raw material to prepare the high-temperature bauxite calcination rotary kiln refractory material. The high-temperature bauxite calcined rotary kiln refractory material with a spherical pore structure is prepared by adopting a pore-forming mechanism of reaction diffusion, and the prepared product has the excellent characteristics of high temperature resistance, corrosion resistance, wear resistance and thermal shock resistance, and can meet the use requirements of a high-temperature kiln lining working layer.

Description

Technical Field

[0001] The invention relates to the technical field of high temperature resistant materials, in particular to a preparation process of refractory materials for high temperature bauxite calcining rotary kiln. Background Art

[0002] In addition to calcining cement clinker, rotary kiln is also used to calcine clay, limestone and dry slag. When calcining raw materials in rotary kiln, the calcination temperature in the furnace is over one thousand degrees Celsius. Therefore, refractory materials with higher melting points are needed as the lining of the kiln body to protect the kiln wall.

[0003] In the prior art, bauxite calcining kilns generally use silica-molybdenum bricks, corundum, mullite bricks, etc. Due to the temperature limit of the kiln lining, it is impossible to achieve ultra-high temperature calcination to produce high-grade bauxite. Most of the calcination temperatures are in the 1550-1650℃ section. The calcination temperature of bauxite clinker with 70-85% aluminum content is generally low, and the product quality is unstable and the grade is low. In addition, the life of the kiln lining is about 6-8 months, and frequent replacement leads to high costs. For example, the Chinese invention patent with the publication number CN105481404A and the patent name: "Refractory Materials for Rotary Kiln Furnaces" has a formula of refractory materials: 9 parts of silicon carbide, 10 parts of corundum, 15 parts of quartz sandstone, 4 parts of zirconium oxide, 4 parts of aluminum sulfate, 2 parts of pyrophyllite, 5 parts of barium sulfate, 5 parts of magnesium sulfate, and 60 parts of silicate cement. This invention patent utilizes the hydration ability of magnesium sulfate, but magnesium sulfate will decompose when heated to 700℃~800℃, has poor chemical stability, and due to the quality constraints of the original ore, it is difficult to obtain high-purity and high-quality products, and it is even more difficult to promote and apply it widely.

[0004] In view of this, it is of great significance to develop and research a high-temperature bauxite calcining rotary kiln refractory material and its preparation method to solve the problem of refractory insulation under ultra-high temperature calcination and achieve energy saving and consumption reduction. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the purpose of the present invention is to provide a preparation process for refractory materials for high-temperature bauxite calcining rotary kiln, select reasonable insulation materials and measures, solve the problem of refractory insulation under ultra-high temperature calcination state, achieve energy saving and consumption reduction, solve the difficulty in material selection of refractory materials for ultra-high temperature calcination, and solve the problem of refractory life under ultra-high temperature calcination conditions.

[0006] To achieve the above object, the present invention provides the following technical solution: a process for preparing a refractory material for a high-temperature bauxite calcining rotary kiln, which is prepared from the following raw materials in parts by weight: 50-55 parts of plate-shaped corundum particles; 5-10 parts of magnesium aluminum spinel particles; 4-6 parts of α-alumina powder; 25-30 parts of plate-like corundum fine powder; 0.1-0.15 parts of binder; 25-50 parts of water.

[0007] As a further solution of the present invention: wherein the particle size of the α-alumina micropowder is 300-350 meshes, the particle size of the plate-like corundum fine powder is 180-220 meshes, and the binder is sodium phosphate.

[0008] The preparation process of refractory materials for high-temperature bauxite calcining rotary kiln includes the following steps: S1: evenly mix the formulated amount of plate-like corundum particles, magnesia-aluminum spinel particles, plate-like corundum fine powder and water, and ball-mill the mixed materials for 3 to 5 hours to obtain a mixed slurry; S2: The mixed slurry prepared in step S1 is spray granulated by a high-speed centrifugal spray granulation dryer to obtain spherical fine particles, and then the spherical fine particles are calcined at 1200-1300°C to obtain lightweight porous small balls, wherein the lightweight porous small balls have a stacking weight of ≤0.7 g / cm 3 , particle size is 0.05~0.3mm; S3: The lightweight porous balls prepared in step S2 are mixed with α-alumina powder and a binder in proportion, stirred evenly, pressed into shape at a pressure of 10 to 30 MPa, and calcined at 1600 to 1800° C. for 6 to 8 hours to obtain high-temperature bauxite calcined rotary kiln refractory materials.

[0009] As a further scheme of the present invention: the high-speed centrifugal spray granulation dryer includes a drying bin, a discharge pipe is fixedly connected to the bottom end of the drying bin, a cyclone separator is fixedly connected to one end of the discharge pipe, an air outlet pipe is fixedly connected to the top of the cyclone separator, a bag dust collector is fixedly connected to one end of the air outlet pipe, a feed pipe and an air inlet pipe are fixedly connected to the top of the drying bin, an atomizing nozzle is fixedly installed on the top of the inner wall of the drying bin, an air outlet is provided on the top of the inner wall of the drying bin located on the outside of the atomizing nozzle, the feed pipe is connected to the atomizing nozzle, the air inlet pipe is connected to the air outlet, the bottom end of the cyclone separator is provided with a discharge port, the material discharged from the cyclone separator is collected by a collecting mechanism, and the air entering the air outlet pipe is filtered by a filtering mechanism.

[0010] As a further solution of the present invention: the collecting mechanism includes a mounting shell, the mounting shell is fixedly connected to the bottom end of the discharge port, the inner wall of the mounting shell is threadedly connected to a collecting bucket, the inner wall of the discharge port is fixedly connected to a mounting plate, the interior of the mounting plate is slidably connected to a vertical rod, the top of the vertical rod is located in the inner cavity of the cyclone separator and is fixedly connected to a conical frame, the interior of the mounting plate is located on one side of the vertical rod and is rotatably connected to a first spur gear, one end of the first spur gear is fixedly connected to a rotating block, the rotating block is located outside the discharge port, the bottom end of the vertical rod is fixedly connected to a horizontal plate, and a horizontal groove is provided on the top of the inner wall of the mounting shell. The interior of the mounting shell is slidably connected with an extrusion frame extending to the inner cavity of the transverse groove, a first spring is connected between the extrusion frame and the mounting shell, the interior of the mounting shell is located at the bottom end of the extrusion frame and is rotatably connected with a second spur gear, the interior of the mounting shell is located at the bottom end of the second spur gear and is slidably connected with a reinforcement block, the reinforcement block extends to the inner wall of the mounting shell, a reinforcement groove is provided on the outer wall of the collecting barrel, a fixing ring is fixedly connected to the top of the collecting barrel, a fixing frame is fixedly connected to the top of the inner wall of the mounting shell on one side of the transverse groove, a card block is slidably connected to the inner wall of the fixing frame, and a second spring is connected between the fixing frame and the card block.

[0011] As a further scheme of the present invention: the filtering mechanism includes a filter plate, which is fixedly connected to the bottom end of the air outlet pipe, the top end of the conical frame is rotatably connected to a rotating rod that penetrates the filter plate, the top end of the rotating rod is fixedly connected to a cross bar, the inner wall of the air outlet pipe is provided with two spiral grooves for the cross bar to slide, the bottom end of the filter plate is rotatably connected to a rotating seat, the outer wall of the rotating seat is fixedly connected to a scraper plate, the filter plate is rotatably connected to the upper outer wall of the rotating seat, the inner wall of the rotating seat is fixedly connected to a slider, and the outer wall of the rotating rod is provided with a sliding groove for the slider to slide.

[0012] As a further solution of the present invention: a first tooth groove is formed on the outer wall of the vertical rod, and the first tooth groove is meshed with the first spur gear.

[0013] As a further solution of the present invention: the outer wall of the transverse plate is in contact with the inner wall of the transverse groove, and a first inclined surface is provided at one end of the extrusion frame located in the inner cavity of the transverse groove.

[0014] As a further solution of the present invention: the outer walls of the extrusion frame and the reinforcement block are both provided with second tooth grooves, the second tooth grooves are meshed with the second spur gears, and the outer wall of one end of the reinforcement block is in contact with the inner wall of the reinforcement groove.

[0015] As a further solution of the present invention: a second inclined surface is provided at the bottom end of the clamping block, and the outer wall of the clamping block is in contact with the inner wall of the fixing frame.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The high-temperature bauxite calcined rotary kiln refractory material prepared by the present invention uses plate-like corundum particles, magnesia-alumina spinel particles, α-alumina micropowder, and plate-like corundum fine powder as main raw materials, and adopts an in-situ decomposition method to prepare high-calcium oxide / alumina porous small balls. Then, the high-calcium oxide / alumina porous small balls are combined with alumina raw materials, and a reaction-diffusion pore-forming mechanism is adopted to prepare a high-temperature bauxite calcined rotary kiln refractory material with a spherical pore structure. The prepared product has excellent properties of high temperature resistance, corrosion resistance, wear resistance, and thermal shock resistance, and can meet the requirements of the use of the working layer of the lining of a high-temperature kiln.

[0017] 2. The high-temperature bauxite calcining rotary kiln refractory material prepared by the present invention has simple preparation steps and is easy to operate. It solves the problem of refractory insulation under ultra-high temperature calcination conditions, achieves the purpose of energy saving and consumption reduction, and is suitable for large-scale mass production.

[0018] 3. The present invention is designed and developed a centrifugal spray granulation dryer in accordance with the improved preparation process. The centrifugal spray granulation dryer is provided with a collecting mechanism. When the rotating block is rotated, the conical frame is brought into contact with the inner wall of the cyclone separator to block the discharge port. The material is stored at the top of the conical frame and the collecting barrel is disassembled. When the collecting barrel is installed, the collecting barrel is installed into the installation shell. At this time, the displacement of the collecting barrel drives the card block to move, and the blocking of the transverse groove is cancelled. At this time, the rotating block can be rotated to drive the transverse plate into the transverse groove. At the same time, the conical frame is opened, and the material falls into the collecting barrel again. The reinforcing block is displaced and inserted into the reinforcing groove to reinforce the collecting barrel to prevent the collecting barrel from loosening, so that the collecting barrel can be replaced without stopping the machine. 4. The centrifugal spray granulation dryer is provided with a filtering mechanism. The hot air is discharged from the cyclone separator through the air outlet pipe. When the hot air passes through the filter plate, the filter plate filters the hot air. When the conical frame moves, the displacement of the conical frame drives the rotating rod to move and rotate. The rotation of the rotating rod drives the scraper plate to rotate. The rotation of the scraper plate scrapes the outer wall of the filter plate to prevent the surface of the filter plate from being blocked and affecting the filtering effect. It is convenient to filter the hot air entering the air outlet pipe and automatically scrape the surface of the filter plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the centrifugal spray granulation dryer of the present invention; Figure 2 It is a schematic diagram of the internal structure of the drying chamber of the centrifugal spray granulation dryer of the present invention; Figure 3 It is a schematic structural diagram of a cyclone separator of the centrifugal spray granulation dryer of the present invention; Figure 4 It is a schematic diagram of the internal structure of the cyclone separator of the centrifugal spray granulation dryer of the present invention; Figure 5 It is a schematic diagram of the installation of the collecting barrel of the centrifugal spray granulation dryer of the present invention; Figure 6 It is a schematic diagram of the internal structure of the collecting barrel of the centrifugal spray granulating dryer of the present invention; Figure 7 It is a schematic structural diagram of the mounting plate and the vertical rod of the centrifugal spray granulation dryer of the present invention; Figure 8 It is a structural schematic diagram of a clamping block and a fixing frame of the centrifugal spray granulating dryer of the present invention; Fig. 9 It is a schematic diagram of the internal structure of the air outlet pipe of the centrifugal spray granulation dryer of the present invention; Fig.10 It is a structural schematic diagram of the scraper plate of the centrifugal spray granulation dryer of the present invention; Fig.11 The figure is a schematic structural diagram of the filter plate, the rotating seat and the rotating rod of the centrifugal spray granulating dryer of the present invention.

[0020] In the figure: 1, drying bin; 2, discharge pipe; 3, cyclone separator; 4, air outlet pipe; 5, bag filter; 6, collecting mechanism; 601, mounting shell; 602, collecting bucket; 603, mounting plate; 604, vertical rod; 605, cone frame; 606, first spur gear; 607, rotating block; 608, horizontal plate; 609, horizontal groove; 610, extrusion frame; 611, first spring; 612, second spur gear; 613, Reinforcement block; 614, reinforcement groove; 615, fixing ring; 616, fixing frame; 617, clamping block; 618, second spring; 7, filtering mechanism; 701, filter plate; 702, rotating rod; 703, cross bar; 704, spiral groove; 705, rotating seat; 706, scraper plate; 707, slider; 708, slide groove; 8, feed pipe; 9, air inlet pipe; 10, atomizing nozzle; 11, air outlet; 12, discharge port. DETAILED DESCRIPTION

[0021] 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.

[0022] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The following is an explanation of an embodiment of the present invention based on the overall structure of the present invention.

[0023] Example 1 The invention discloses a preparation process of a refractory material for a high-temperature bauxite calcining rotary kiln. The high-temperature bauxite calcining rotary kiln refractory material is prepared from the following raw materials in parts by weight: 50 parts of plate-shaped corundum particles; 10 parts of magnesium aluminum spinel particles; 6 parts of α-alumina powder; 25 parts of plate-like corundum fine powder; Sodium phosphate 0.1 part; 25 parts water.

[0024] The particle size of the α-alumina micropowder is 300-350 meshes.

[0025] The particle size of the plate-like corundum fine powder is 180-220 meshes.

[0026] See also Figures 1 to 11 In the embodiment of the present invention, the preparation process of the refractory material for high temperature bauxite calcining rotary kiln comprises the following specific steps: S1: evenly mix the formulated amount of plate-like corundum particles, magnesia-aluminum spinel particles, plate-like corundum fine powder and water, and ball-mill the mixed materials for 3 hours to obtain a mixed slurry; S2: spray granulate the mixed slurry prepared in step S1 to obtain spherical fine particles, and then calcine the spherical fine particles at 1200-1300° C. to obtain lightweight porous small balls; the accumulation is ≤0.7 g / cm3, and the particle size is 0.05-0.3 mm.

[0027] S3: The lightweight porous balls prepared in step S2 are mixed with α-alumina powder and a binder in proportion, stirred evenly, pressed into shape under a pressure of 10 MPa, and calcined at 1600° C. for 6 hours to obtain high-temperature bauxite calcined rotary kiln refractory materials.

[0028] Please refer to Figures 1 to 3 The high-speed centrifugal spray granulation dryer includes a drying bin 1, a discharge pipe 2 is fixedly connected to the bottom end of the drying bin 1, a cyclone separator 3 is fixedly connected to one end of the discharge pipe 2, an air outlet pipe 4 is fixedly connected to the top of the cyclone separator 3, a bag dust collector 5 is fixedly connected to one end of the air outlet pipe 4, a feed pipe 8 and an air inlet pipe 9 are fixedly connected to the top of the drying bin 1, an atomizing nozzle 10 is fixedly installed on the top of the inner wall of the drying bin 1, an air outlet 11 is arranged on the outside of the atomizing nozzle 10 at the top of the inner wall of the drying bin 1, the feed pipe 8 is connected to the atomizing nozzle 10, the air inlet pipe 9 is connected to the air outlet 11, a discharge port 12 is arranged at the bottom end of the cyclone separator 3, the material discharged from the cyclone separator 3 is collected by a collecting mechanism 6, and the air entering the air outlet pipe 4 is filtered by a filtering mechanism 7.

[0029] In this embodiment: the material is transported to the atomizing nozzle 10 through the feed pipe 8 for atomization and spraying, and the air inlet pipe 9 transports hot air to be sprayed through the air outlet 11, and the hot air contacts the atomized particles for drying. The dried material and hot air are transported to the cyclone separator 3 through the discharge pipe 2 for separation, and the obtained granular material is collected through the collection mechanism 6. The hot air is discharged into the bag filter 5 through the air outlet pipe 4 and discharged after filtering. Through the high-speed centrifugal spray granulation dryer, the various components of the mixed slurry are more uniform and have good thermal stability after granulation.

[0030] Please refer to Figures 3 to 8The collecting mechanism 6 includes a mounting shell 601, which is fixedly connected to the bottom end of the discharge port 12, and a collecting barrel 602 is threadedly connected to the inner wall of the mounting shell 601. A mounting plate 603 is fixedly connected to the inner wall of the discharge port 12, and a vertical rod 604 is slidably connected inside the mounting plate 603. The top of the vertical rod 604 is located in the inner cavity of the cyclone separator 3 and is fixedly connected to a conical frame 605. The inside of the mounting plate 603 is located on one side of the vertical rod 604 and is rotatably connected to a first straight gear 606. One end of the first straight gear 606 is fixedly connected to a rotating block 607, and the rotating block 607 is located outside the discharge port 12. A horizontal plate 608 is fixedly connected to the bottom end of the vertical rod 604. A horizontal groove 609 is provided on the top of the inner wall of the mounting shell 601. The inner sliding surface of the mounting shell 601 An extrusion frame 610 is connected to extend to the inner cavity of the transverse groove 609, a first spring 611 is connected between the extrusion frame 610 and the mounting shell 601, the interior of the mounting shell 601 is located at the bottom end of the extrusion frame 610 and is rotatably connected to the second spur gear 612, the interior of the mounting shell 601 is located at the bottom end of the second spur gear 612 and is slidably connected to a reinforcement block 613, the reinforcement block 613 extends to the inner wall of the mounting shell 601, a reinforcement groove 614 is opened on the outer wall of the collecting barrel 602, a fixing ring 615 is fixedly connected to the top of the collecting barrel 602, a fixing frame 616 is fixedly connected to the top of the inner wall of the mounting shell 601 on one side of the transverse groove 609, a clamping block 617 is slidably connected to the inner wall of the fixing frame 616, and a second spring 618 is connected between the fixing frame 616 and the clamping block 617.

[0031] In this embodiment, when the collecting barrel 602 is installed in the mounting shell 601, the second spring 618 is in a stretched state, the conical frame 605 does not contact the inner wall of the cyclone separator 3, and the material enters the collecting barrel 602 along the inner wall of the cyclone separator 3 through the discharge port 12 for collection operation. When the collecting barrel 602 is full, the rotating block 607 can be rotated, and the rotating block 607 rotates to drive the first straight gear 606 to rotate, and the first straight gear 606 rotates to drive the vertical rod 604 to move, and the vertical rod 604 moves with the displacement of The movable conical frame 605 contacts the inner wall of the cyclone separator 3 to block the discharge port 12. At this time, the material that continues to fall is stored at the top of the conical frame 605; at the same time, the vertical rod 604 is displaced to drive the cross plate 608 to move out of the cross groove 609. At this time, the collection barrel 602 can be dismantled. When the collection barrel 602 is dismantled, the block 617 is displaced to between the cross plate 608 and the cross groove 609 by the elastic force of the second spring 618 to prevent the cross plate 608 from moving in the opposite direction and causing the conical frame 605 to loosen and cause the material to fall out.

[0032] When the collecting barrel 602 is installed, the collecting barrel 602 is installed into the installing shell 601. At this time, the displacement of the collecting barrel 602 drives the fixing ring 615 to move. The displacement of the fixing ring 615 pushes the two clamping blocks 617 to move in opposite directions, causing the second spring 618 to be stretched. The clamping block 617 cancels the blocking of the transverse groove 609. At this time, the rotating block 607 can be rotated to drive the transverse plate 608 to enter the transverse groove 609. At the same time, the conical frame 605 is opened, and the material falls into the collecting barrel 602 again. During the process of the transverse plate 608 entering the transverse groove 609, the transverse plate 608 contacts the extrusion frame 610, pushing the extrusion frame 610 to move, causing the first spring 611 to be squeezed. The displacement of the extrusion frame 610 drives the second spur gear 612 to rotate. The rotation of the second spur gear 612 drives the reinforcement block 613 to move and insert it into the reinforcement groove 614, so as to reinforce the collecting barrel 602 to prevent the collecting barrel 602 from loosening, so as to facilitate the replacement of the collecting barrel 602 without stopping the machine.

[0033] Please refer to Figures 9 to 11 The filtering mechanism 7 includes a filter plate 701, which is fixedly connected to the bottom end of the air outlet pipe 4. The top of the conical frame 605 is rotatably connected to a rotating rod 702 that penetrates the filter plate 701. The top of the rotating rod 702 is fixedly connected to a cross bar 703. The inner wall of the air outlet pipe 4 is provided with two spiral grooves 704 for the cross bar 703 to slide (the two spiral grooves 704 are arranged in a DNA double helix shape, and the spiral rise angle is greater than 50 degrees). The bottom end of the filter plate 701 is rotatably connected to a rotating seat 705, and the outer wall of the rotating seat 705 is fixedly connected to a scraping plate 706. The filter plate 701 is rotatably connected to the outer wall of the upper end of the rotating seat 705, and the inner wall of the rotating seat 705 is fixedly connected to a slider 707. The outer wall of the rotating rod 702 is provided with a sliding groove 708 for the slider 707 to slide.

[0034] In this embodiment, the hot air is discharged from the cyclone separator 3 through the air outlet pipe 4. When the hot air passes through the filter plate 701, the filter plate 701 filters the hot air to prevent the material from being discharged with the hot air. When the conical frame 605 moves, the displacement of the conical frame 605 drives the rotating rod 702 to move. At this time, the slider 707 slides relatively in the slide groove 708. The displacement of the rotating rod 702 drives the cross bar 703 to move. The two ends of the cross bar 703 are respectively inserted into the two spiral grooves 704 (in order to reduce the friction coefficient between the cross bar 703 and the spiral groove 704, the cross bar 703 can be A freely rotatable ball is embedded at the end, and the ball is in sliding contact with the inner wall of the spiral groove 704), and is displaced along the spiral groove 704, thereby driving the rotating rod 702 to rotate. The rotating rod 702 rotates through the slider 707 to drive the rotating seat 705 to rotate. The rotating seat 705 rotates to drive the scraper plate 706 to rotate. The scraper plate 706 rotates to scrape the outer wall of the filter plate 701 to prevent the surface of the filter plate 701 from being blocked and affecting the filtering effect, so as to facilitate the filtering of the hot air entering the air outlet duct 4 and automatically scrape the surface of the filter plate 701.

[0035] Please refer to Figures 3 to 8 A first tooth groove is formed on the outer wall of the vertical rod 604 , and the first tooth groove is meshed with the first spur gear 606 .

[0036] In this embodiment, the rotating block 607 is rotated, the rotating block 607 drives the first spur gear 606 to rotate, the first spur gear 606 drives the vertical rod 604 to move, and the displacement of the vertical rod 604 drives the conical frame 605 to contact the inner wall of the cyclone separator 3.

[0037] Please refer to Figures 3 to 8 The outer wall of the horizontal plate 608 is in contact with the inner wall of the horizontal groove 609, and a first inclined surface is provided at one end of the extrusion frame 610 located in the inner cavity of the horizontal groove 609. The outer walls of the extrusion frame 610 and the reinforcement block 613 are both provided with second tooth grooves, and the second tooth grooves are meshed with the second spur gear 612. The outer wall of one end of the reinforcement block 613 is in contact with the inner wall of the reinforcement groove 614.

[0038] In this embodiment: when the horizontal plate 608 enters the horizontal groove 609, the horizontal plate 608 contacts the extrusion frame 610, pushing the extrusion frame 610 to move, causing extrusion on the first spring 611, and the displacement of the extrusion frame 610 drives the second spur gear 612 to rotate. The rotation of the second spur gear 612 drives the reinforcement block 613 to move and insert into the reinforcement groove 614, thereby reinforcing the collection barrel 602.

[0039] Please refer to Figures 3 to 8 A second inclined surface is provided at the bottom end of the block 617 , and the outer wall of the block 617 is in contact with the inner wall of the fixing frame 616 .

[0040] In this embodiment: the collecting barrel 602 is installed into the installation shell 601 , and the displacement of the collecting barrel 602 drives the fixing ring 615 to move, and the displacement of the fixing ring 615 pushes the block 617 to move, causing the second spring 618 to be stretched, and the block 617 cancels the blocking of the transverse groove 609 .

[0041] Example 2 The invention discloses a preparation process of a refractory material for a high-temperature bauxite calcining rotary kiln. The high-temperature bauxite calcining rotary kiln refractory material is prepared from the following raw materials in parts by weight: 53 parts of plate-like corundum particles; 5 parts of magnesium aluminum spinel particles; 5 parts of α-alumina powder; 28 parts of plate-like corundum fine powder; Sodium phosphate 0.13 parts; 38 parts water.

[0042] The preparation process of refractory materials for high-temperature bauxite calcining rotary kiln, the specific steps are as follows: S1: evenly mix the formulated amount of plate-like corundum particles, magnesia-aluminum spinel particles, plate-like corundum fine powder and water, and ball-mill the mixed materials for 4 hours to obtain a mixed slurry; S2: spray granulate the mixed slurry prepared in step S1 to obtain spherical fine particles, and then calcine the spherical fine particles at 1200-1300° C. to obtain lightweight porous small balls; the accumulation is ≤0.7 g / cm3, and the particle size is 0.05-0.3 mm.

[0043] S3: The lightweight porous balls prepared in step S2 are mixed with α-alumina powder and a binder in proportion, stirred evenly, pressed into shape at a pressure of 20 MPa, and calcined at 1700° C. for 7 hours to obtain high-temperature bauxite calcined rotary kiln refractory materials.

[0044] The rest of the preparation method and application equipment are the same as those in Example 1 and will not be described in detail here.

[0045] Example 3 The invention discloses a preparation process of a refractory material for a high-temperature bauxite calcining rotary kiln. The high-temperature bauxite calcining rotary kiln refractory material is prepared from the following raw materials in parts by weight: 55 parts of plate-like corundum particles; 8 parts of magnesium aluminum spinel particles; 4 parts of α-alumina powder; 30 parts of plate-like corundum fine powder; 0.15 parts of sodium phosphate; 50 parts of water.

[0046] The preparation process of refractory materials for high-temperature bauxite calcining rotary kiln, the specific steps are as follows: S1: evenly mix the formulated amount of plate-like corundum particles, magnesia-aluminum spinel particles, plate-like corundum fine powder and water, and ball-mill the mixed materials for 5 hours to obtain a mixed slurry; S2: spray granulate the mixed slurry prepared in step S1 to obtain spherical fine particles, and then calcine the spherical fine particles at 1200-1300° C. to obtain lightweight porous small balls; the accumulation is ≤0.7 g / cm3, and the particle size is 0.05-0.3 mm.

[0047] S3: The lightweight porous balls prepared in step S2 are mixed with α-alumina powder and a binder in proportion, stirred evenly, pressed into shape at a pressure of 30 MPa, and calcined at 1800° C. for 8 hours to obtain high-temperature bauxite calcined rotary kiln refractory materials.

[0048] The preparation method and application equipment are the same as those in Example 1 and will not be described in detail here.

[0049] Results comparison: The high temperature bauxite calcined rotary kiln refractory materials prepared in the above Examples 1 to 3 were tested respectively, and the test performance indicators are shown in Table 1.

[0050] Table 1- High temperature bauxite calcining rotary kiln refractory material performance test

[0051] In summary, the high-temperature bauxite calcined rotary kiln refractory product prepared by the present invention has an aluminum oxide content higher than 96%, high compressive strength and flexural strength, good corrosion resistance, wear resistance and thermal shock resistance, and can meet the requirements for use of the working layer of a high-temperature kiln.

[0052] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A process for preparing refractory materials for high temperature bauxite calcining rotary kiln, characterized in that , The refractory material for high temperature bauxite calcining rotary kiln is made from the following raw materials in parts by weight: 50-55 parts of plate-shaped corundum particles; 5-10 parts of magnesium aluminum spinel particles; 4-6 parts of α-alumina powder; 25-30 parts of plate-like corundum fine powder; 0.1-0.15 parts of binder; 25-50 parts of water.

2. The process for preparing refractory materials for high temperature bauxite calcining rotary kiln according to claim 1, characterized in that , wherein the particle size of the α-alumina micropowder is 300-350 meshes, the particle size of the plate-like corundum fine powder is 180-220 meshes, and the binder is sodium phosphate.

3. The process for preparing refractory material for high temperature bauxite calcining rotary kiln according to claim 1, characterized in that , including the following steps: S1: evenly mix the formulated amount of plate-like corundum particles, magnesia-aluminum spinel particles, plate-like corundum fine powder and water, and ball-mill the mixed materials for 3 to 5 hours to obtain a mixed slurry; S2: The mixed slurry prepared in step S1 is spray granulated by a high-speed centrifugal spray granulation dryer to obtain spherical fine particles, and then the spherical fine particles are calcined at 1200-1300°C to obtain lightweight porous small balls, wherein the lightweight porous small balls have a stacking weight of ≤0.7 g / cm 3 , particle size is 0.05~0.3mm; S3: The lightweight porous balls prepared in step S2 are mixed with α-alumina powder and a binder in proportion, stirred evenly, pressed into shape at a pressure of 10 to 30 MPa, and calcined at 1600 to 1800° C. for 6 to 8 hours to obtain high-temperature bauxite calcined rotary kiln refractory materials.

4. The process for preparing refractory materials for high temperature bauxite calcining rotary kiln according to claim 3, characterized in that: The high-speed centrifugal spray granulation dryer comprises a drying bin (1), the bottom end of the drying bin (1) is fixedly connected to a discharge pipe (2), one end of the discharge pipe (2) is fixedly connected to a cyclone separator (3), the top end of the cyclone separator (3) is fixedly connected to an air outlet pipe (4), one end of the air outlet pipe (4) is fixedly connected to a bag dust collector (5), the top end of the drying bin (1) is fixedly connected to a feed pipe (8) and an air inlet pipe (9), and an atomizing nozzle is fixedly installed on the top end of the inner wall of the drying bin (1). (10), an air outlet (11) is provided at the top of the inner wall of the drying chamber (1) and is located outside the atomizing nozzle (10), the feed pipe (8) is connected to the atomizing nozzle (10), the air inlet pipe (9) is connected to the air outlet (11), and a discharge port (12) is provided at the bottom end of the cyclone separator (3), the material discharged from the cyclone separator (3) is collected by a collecting mechanism (6), and the air entering the air outlet pipe (4) is filtered by a filtering mechanism (7).

5. The process for preparing refractory material for high temperature bauxite calcining rotary kiln according to claim 4, characterized in that: The collecting mechanism (6) comprises a mounting shell (601), the mounting shell (601) being fixedly connected to the bottom end of the discharge port (12), the inner wall of the mounting shell (601) being threadedly connected to a collecting bucket (602), the inner wall of the discharge port (12) being fixedly connected to a mounting plate (603), the interior of the mounting plate (603) being slidably connected to a vertical rod (604), the top end of the vertical rod (604) being located in the inner cavity of the cyclone separator (3) and being fixedly connected to a conical frame (604). 5), the interior of the mounting plate (603) is located on one side of the vertical rod (604) and is rotatably connected to a first spur gear (606), one end of the first spur gear (606) is fixedly connected to a rotating block (607), the rotating block (607) is located outside the discharge port (12), the bottom end of the vertical rod (604) is fixedly connected to a horizontal plate (608), the top end of the inner wall of the mounting shell (601) is provided with a horizontal groove (609), the interior of the mounting shell (601) is slidably connected to the The extrusion frame (610) is connected to the inner cavity of the transverse groove (609), a first spring (611) is connected between the extrusion frame (610) and the mounting shell (601), the interior of the mounting shell (601) is located at the bottom end of the extrusion frame (610) and is rotatably connected to a second spur gear (612), the interior of the mounting shell (601) is located at the bottom end of the second spur gear (612) and is slidably connected to a reinforcement block (613), and the reinforcement block (613) extends to the mounting shell (601). The inner wall of the mounting shell (601) and the outer wall of the collecting barrel (602) are provided with a reinforcement groove (614); the top of the collecting barrel (602) is fixedly connected to a fixing ring (615); the top of the inner wall of the mounting shell (601) is located on one side of the transverse groove (609) and is fixedly connected to a fixing frame (616); the inner wall of the fixing frame (616) is slidably connected to a clamping block (617); and a second spring (618) is connected between the fixing frame (616) and the clamping block (617).

6. The process for preparing refractory materials for high temperature bauxite calcining rotary kiln according to claim 5, characterized in that: The filtering mechanism (7) comprises a filter plate (701), the filter plate (701) being fixedly connected to the bottom end of the air outlet pipe (4), the top end of the conical frame (605) being rotatably connected to a rotating rod (702) penetrating the filter plate (701), the top end of the rotating rod (702) being fixedly connected to a cross rod (703), the inner wall of the air outlet pipe (4) being provided with two spiral grooves (704) for the cross rod (703) to slide, the bottom end of the filter plate (701) being rotatably connected to a rotating seat (705), the outer wall of the rotating seat (705) being fixedly connected to a scraping plate (706), the filter plate (701) being rotatably connected to the outer wall of the upper end of the rotating seat (705), the inner wall of the rotating seat (705) being fixedly connected to a sliding block (707), and the outer wall of the rotating rod (702) being provided with a sliding groove (708) for the sliding block (707) to slide.

7. The process for preparing refractory materials for high temperature bauxite calcining rotary kiln according to claim 5, characterized in that: The outer wall of the vertical rod (604) is provided with a first tooth groove, and the first tooth groove is meshed with the first spur gear (606).

8. The process for preparing refractory materials for high temperature bauxite calcining rotary kiln according to claim 5, characterized in that: The outer wall of the transverse plate (608) fits the inner wall of the transverse groove (609), and a first inclined surface is provided at one end of the extrusion frame (610) located in the inner cavity of the transverse groove (609).

9. The process for preparing refractory materials for high temperature bauxite calcining rotary kiln according to claim 5, characterized in that: The outer walls of the extrusion frame (610) and the reinforcement block (613) are both provided with a second tooth groove, the second tooth groove is meshed with the second spur gear (612), and the outer wall of one end of the reinforcement block (613) is in contact with the inner wall of the reinforcement groove (614).

10. The process for preparing refractory material for high temperature bauxite calcining rotary kiln according to claim 6, characterized in that: A second inclined surface is provided at the bottom end of the clamping block (617), and the outer wall of the clamping block (617) fits the inner wall of the fixing frame (616).

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