Preparation process of aluminum oxide composite fiberboard

Abstract

The invention relates to a preparation process of an aluminum oxide composite fiberboard in the field of refractory materials, which comprises the following steps: when a prefabricated emulsion and oxidized fiber loose cotton are mixed, through a guide cylinder and a guide plate which are arranged above a mixing impeller, the circulating flow of the prefabricated emulsion is realized, and a curtain-shaped liquid film is formed on the inner wall of the guide cylinder when the prefabricated emulsion flows back downwards; meanwhile, a rotatable material distribution pipe is matched, so that the alumina cellosilk is in full contact with the prefabricated emulsion which circularly flows and is paved in a curtain shape, and the dispersion uniformity of the oxidized cellosilk in the prefabricated emulsion is improved; besides, through the arrangement of a fixing cylinder with a comb tooth roller and a blowing pipe communicated with a high-pressure air pump, the block-shaped aluminum oxide fiber loose cotton is dispersed into single-strand fiber yarn, the probability that the aluminum oxide fiber yarn is flocculated and agglomerated in the prefabricated emulsion is reduced, the dispersion uniformity of the aluminum oxide fiber yarn in the prefabricated emulsion is further improved, and the dispersion uniformity of the aluminum oxide fiber yarn in the prefabricated emulsion is improved. And the uniformity of the fiber slurry is improved.

Description

Technical Field

[0001] The invention relates to a fiberboard preparation process, in particular to a preparation process of an alumina composite fiberboard applied in the field of refractory materials. Background Art

[0002] Alumina fiberboard is a high-performance refractory insulation material, mainly composed of alumina (Al2O3) and containing about 5% silicon dioxide (SiO2) to stabilize the crystal phase. This material is prepared by the high-tech "sol-gel" method and has excellent high temperature resistance, wear resistance, corrosion resistance and good thermal insulation performance. It has excellent high temperature resistance and can withstand temperatures up to 1600°C or even higher. It is an ideal insulation material for high-temperature industrial furnaces, pipelines and equipment. The unique fiber structure of alumina fiberboard gives it extremely low thermal conductivity, which can effectively prevent heat transfer and significantly reduce energy consumption.

[0003] In the preparation process of alumina fiberboard, the preparation of uniformly dispersed slurry is a key link. This step requires the precise feeding of various component raw materials into a high-speed mixer in order to achieve uniform distribution of alumina fibers in the slurry emulsion. However, traditional high-speed mixing technology faces a challenge in actual operation: alumina fibers tend to flocculate during the stirring and mixing process to form fiber clusters. This phenomenon not only significantly hinders the uniform dispersion of alumina fibers in the prefabricated slurry, but also further adversely affects the quality of subsequent alumina fiberboard products. Therefore, optimizing the mixing process to effectively prevent fiber flocculation and ensure slurry uniformity has become an important research direction for improving the quality of alumina fiberboard.

[0004] The existing patent with publication number CN109320273A discloses an improved alumina fiberboard product, which is characterized in that, based on the existing fiberboard preparation process, alkaline silica sol is used as an inorganic binder to prepare a low-density, high-strength fiberboard. At the same time, near-infrared sunscreens such as rutile titanium dioxide or potassium hexatitanate whiskers are doped into the fiberboard to further reduce its high-temperature thermal conductivity. The room temperature compressive strength of the prepared alumina fiberboard is 4.5-5.6MPa. When the sample size is 1cm thick, in steady state, the hot surface temperature is 1000℃, the cold surface temperature is 300-320℃, the hot surface temperature is 1200℃, and the cold surface temperature is 340-360℃; the patent improves the raw material composition and preparation process conditions, but does not disclose how to solve the problem that alumina fibers are easily flocculated during stirring and mixing. Summary of the invention

[0005] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that when preparing the fiber slurry, the alumina fibers are easily flocculated into agglomerates, which affects the uniformity of the dispersion of the alumina fibers in the fiber slurry.

[0006] In order to solve the above problems, the present invention provides a preparation process of an alumina composite fiber board, comprising the following steps:

[0007] Step 1, preparing slurry: putting nano-alumina, nano-zirconium oxide, silicon carbide, siloxane resin and water into a low-speed mixer for stirring and mixing to obtain a prefabricated emulsion;

[0008] Step 2, preparing fiber slurry: putting the prefabricated emulsion obtained in step 1 and alumina fiber loose cotton into a high-speed mixer for stirring to obtain fiber slurry;

[0009] Step three, adjusting the water content; transferring the fiber slurry from step two to a precision filter, and adjusting the water content of the fiber slurry as needed to obtain a dehydrated fiber slurry;

[0010] Step 4, curing: transferring the dehydrated fiber slurry obtained in step 3 to a forming mold, extruding and curing it, and then heating and curing it, and demolding it to obtain a cured fiberboard;

[0011] Step five, calcining; transferring the cured fiberboard obtained in step four to a calcining furnace for calcining to obtain a calcined fiberboard;

[0012] Step 6, cooling and cutting: taking out the calcined fiberboard obtained in step 5 from the calcining furnace and cooling it, and then cutting and shaping it according to production needs to obtain a finished alumina fiberboard;

[0013] The high-speed mixer comprises a mixing drum, a guide drum is arranged inside the mixing drum, an annular cavity is formed between the outer wall of the guide drum and the inner wall of the mixing drum, a plurality of guide plates spanning the annular cavity and fixedly connected to the inner wall of the mixing drum are fixedly connected to the upper end of the guide drum; a mixing impeller is arranged below the guide drum, and the mixing impeller is connected to a first driving mechanism driving the mixing impeller to rotate;

[0014] A distribution pipe rotatably connected to the top plate of the mixing cylinder is provided at the center position of the upper part of the guide cylinder. The distribution pipe is L-shaped and the lower end opening faces the inner wall of the guide cylinder. The upper part of the distribution pipe is connected to a second driving mechanism for driving it to rotate; the upper end of the distribution pipe is rotatably connected to a blowing pipe, one side of the blowing pipe is fixedly connected to a fixed cylinder tangentially arranged therewith, the middle part of the upper end of the fixed cylinder is fixedly connected to a feeding pipe, and the upper end of the feeding pipe is fixedly connected to a feeding hopper;

[0015] An arc-shaped grille plate located below the connecting position between the discharge pipe and the fixed cylinder is fixedly connected to the inner wall of the fixed cylinder, and a plurality of grille holes are provided on the arc-shaped grille plate. A comb-tooth roller is rotatably connected inside the fixed cylinder, and the comb-tooth roller is fixedly connected to the output shaft of the third motor. A plurality of comb-tooth rods matching the grille holes are fixedly connected to the comb-tooth roller. The upper end of the blowing pipe is connected to an external high-pressure air pump through an air inlet pipe.

[0016] In the preparation process of the above-mentioned alumina composite fiber board, the alumina fiber loose cotton is dispersed into single fiber strands and evenly mixed with the prefabricated emulsion through a comb roller, a blowing pipe and a distribution pipe.

[0017] As a further improvement of the present application, a deflocculation mechanism is provided at the lower part of the mixing cylinder, and the deflocculation mechanism includes a plurality of groups of movable pins distributed in a circle and nested in the shell wall of the mixing cylinder, the movable pins are sleeved with springs so that they are received in the shell wall of the mixing cylinder when not subjected to external force, and a fourth driving mechanism for driving the movable pins to extend into the inner cavity of the mixing cylinder is installed in the shell wall of the mixing cylinder, and the fourth driving mechanism periodically pushes the movable pins to be inserted into the inner cavity of the mixing cylinder, and the outer wall of the mixing impeller is fixedly connected with rotating pins arranged in an staggered distribution relative to the movable pins.

[0018] As a further improvement of the present application, the guide cylinder is a vertically arranged cylindrical structure with openings at both ends. The upper end of the guide cylinder is provided with an inwardly inclined annular guide surface, and the opening position at the lower end of the fabric pipe is set at a height lower than the height of the annular guide surface.

[0019] As a further improvement of the present application, the part of the guide plate facing the guide cylinder extends to the annular guide surface, the guide plate is tangent to the inner wall of the guide cylinder in space, and multiple guide plates are distributed equidistantly around the upper end of the guide cylinder.

[0020] As a further improvement of the present application, the first driving mechanism includes a vertical shaft fixedly connected to the mixing impeller and extending to the bottom of the mixing drum, and the vertical shaft is connected to the output shaft of the first motor through a transmission belt; the second driving mechanism includes a second motor fixedly connected to the mixing drum, and the output shaft of the second motor is connected to the distribution pipe for transmission through a transmission gear set.

[0021] As a further improvement of the present application, the blowing tube is a square tube with a rectangular cross-section, the fixed tube is a longitudinally arranged cylindrical structure, the fixed tube is fixedly connected to the mixing tube through a mounting plate, the arc grille plate is a strip plate with an arc-shaped cross-section, the grille holes are arranged along the bending direction of the arc grille plate, and the comb tooth rod is a cylindrical rod.

[0022] As a further improvement of the present application, a clamping cavity is provided at the lower portion of the mixing cylinder, and evenly distributed horizontal holes are provided on the inner side of the mixing cylinder located at the clamping cavity. A movable pin is slidably nested in the horizontal holes and extends into the clamping cavity. The movable pin is a horizontal rod with a spherical end and a needle-shaped end, and the needle-shaped end faces the inner cavity of the mixing cylinder. The fourth driving mechanism includes an extrusion ring slidably nested in the clamping cavity and a lifting mechanism for driving the extrusion ring to move up and down.

[0023] As a further improvement of the present application, the extrusion ring is a circular ring with an inverted L-shaped cross-section, and an extrusion slope is provided on the lower edge of the extrusion ring.

[0024] As a further improvement of the present application, the lifting mechanism is one of an electric push rod and a hydraulic telescopic cylinder.

[0025] As a further improvement of the present application, a sealing ring is fixedly connected in the horizontal hole and sleeved on the outside of the movable pin. The sealing ring is an annular sealing ring and has an interference fit with the movable pin.

[0026] In summary, when the prefabricated emulsion and oxidized fiber loose cotton are mixed in the present invention, the guide cylinder and the guide plate are arranged above the mixing impeller, so that the prefabricated emulsion flows upward along the annular cavity outside the guide cylinder and flows back downward along the inner wall of the guide cylinder, so as to realize the circulation of the prefabricated emulsion and form a curtain-like liquid film on the inner wall of the guide cylinder when flowing back downward; at the same time, with the rotatable distribution tube, the aluminum oxide fiber filaments are fully in contact with the circulating and curtain-like prefabricated emulsion, thereby improving the uniformity of the dispersion of the oxidized fiber filaments in the prefabricated emulsion; in addition, by providing a fixed cylinder with a comb roller and a blowing pipe connected to a high-pressure air pump, the alumina fiber loose cotton in the form of a mass is dispersed into a single fiber filament, thereby reducing the probability of the aluminum oxide fiber filaments agglomerating into a mass in the prefabricated emulsion, further improving the uniformity of the dispersion of the aluminum oxide fiber filaments in the prefabricated emulsion, and improving the uniformity of the fiber slurry. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the three-dimensional structure of the high-speed mixer in this application;

[0028] Figure 2 It is a schematic cross-sectional structure diagram of the high-speed mixer in this application;

[0029] Figure 3 It is a schematic diagram of the three-dimensional structure of the guide cylinder and the guide plate in this application;

[0030] Figure 4 It is a schematic diagram of the three-dimensional structure of the mixing impeller in this application;

[0031] Figure 5 for Figure 2 A schematic diagram of the enlarged structure at A in the middle;

[0032] Figure 6 This is a schematic diagram of the assembly structure of the blowing tube and the fixed tube in this application;

[0033] Figure 7 This is a schematic diagram of the exploded assembly of the material distribution pipe and the material feeding hopper in this application;

[0034] Figure 8 This is a schematic diagram of the three-dimensional structure of the curved grid plate in this application;

[0035] Fig. 9 A schematic diagram of the aluminum oxide fiber bulk blanket being dispersed into single fiber strands in this application;

[0036] Fig.10 A schematic diagram of mixing the prefabricated emulsion and the single-strand fiber filament in this application;

[0037] Fig.11 for Figure 2 A schematic diagram of the enlarged structure at B in the middle;

[0038] Fig.12 It is a schematic diagram of a partial cross-sectional structure of an extrusion ring;

[0039] Fig.13 It is a schematic diagram of the assembly of the movable pin and the spring;

[0040] Fig.14 It is a schematic diagram of the state where the movable pin extends from the wall of the mixing cylinder shell.

[0041] Description of the numbers in the figure:

[0042] 1. Mixing cylinder; 101. Clamping chamber; 102. Horizontal hole; 2. Guide cylinder; 201. Annular guide surface; 3. Guide plate; 4. Mixing impeller; 5. First driving mechanism; 6. Distribution pipe; 7. Second driving mechanism; 8. Blowing pipe; 9. Fixed cylinder; 10. Comb roller; 1001. Comb rod; 11. Third motor; 12. Feeding pipe; 13. Arc grille plate; 1301. Grille hole; 14. Feeding hopper; 15. Inlet pipe; 16. Mounting plate; 17. Movable pin; 18. Spring; 19. Sealing ring; 20. Extrusion ring; 2001. Extrusion slope; 21. Electric push rod; 22. Rotating pin. DETAILED DESCRIPTION

[0043] The following describes two implementation modes of the present application in detail with reference to the accompanying drawings.

[0044] The first implementation method:

[0045] Figure 1-10 A preparation process of an alumina composite fiberboard is shown, comprising the following steps:

[0046] Step 1, preparing slurry: putting nano-alumina, nano-zirconium oxide, silicon carbide, siloxane resin and water into a low-speed mixer for stirring and mixing to obtain a prefabricated emulsion;

[0047] Step 2, preparing fiber slurry: putting the prefabricated emulsion obtained in step 1 and alumina fiber loose cotton into a high-speed mixer for stirring to obtain fiber slurry;

[0048] Step three, adjusting the water content; transferring the fiber slurry from step two to a precision filter, and adjusting the water content of the fiber slurry as needed to obtain a dehydrated fiber slurry;

[0049] Step 4, curing: transferring the dehydrated fiber slurry obtained in step 3 to a forming mold, extruding and curing it, and then heating and curing it, and demolding it to obtain a cured fiberboard;

[0050] Step five, calcining; transferring the cured fiberboard obtained in step four to a calcining furnace for calcining to obtain a calcined fiberboard;

[0051] Step 6, cooling and cutting: taking out the calcined fiberboard obtained in step 5 from the calcining furnace and cooling it, and then cutting and shaping it according to production needs to obtain a finished alumina fiberboard;

[0052] Among them, see Figure 2 The high-speed mixer comprises a mixing drum 1, a guide drum 2 is arranged inside the mixing drum 1, an annular cavity is formed between the outer wall of the guide drum 2 and the inner wall of the mixing drum 1, and a plurality of guide plates 3 are fixedly connected to the upper end of the guide drum 2, which span the annular cavity and are fixedly connected to the inner wall of the mixing drum 1;

[0053] See also Figure 2 and Fig.10 A mixing impeller 4 is provided below the guide cylinder 2, and the mixing impeller 4 is connected to a first driving mechanism 5 for driving the mixing impeller 4 to rotate at a high speed, so that the prefabricated emulsion put into the mixing cylinder 1 is subjected to the centrifugal force to perform eddy motion, and the prefabricated emulsion performing eddy motion moves upward along the annular cavity under the action of the guide cylinder 2, and when the prefabricated emulsion moves to the upper part of the guide cylinder 2, it flows to the inner wall of the guide cylinder 2 under the action of two forces including its own gravity and the guiding action of the guide plate 3, and forms a curtain-like emulsion liquid film on the inner wall of the guide cylinder 2, and when the prefabricated emulsion is out of contact with the guide cylinder 2, it contacts the mixing impeller 4 again, and then enters the annular cavity again under the action of the high-speed impeller 4, so as to realize the up and down circulation flow of the prefabricated emulsion and the circular spreading on the inner wall of the guide cylinder 2;

[0054] See also Figure 2 and Figure 6 A distribution pipe 6 rotatably connected to the top plate of the mixing cylinder 1 is provided at the center position of the upper part of the guide cylinder 2. The distribution pipe 6 is L-shaped and the lower end opening faces the inner wall of the guide cylinder 2. The upper part of the distribution pipe 6 is connected to a second driving mechanism 7 for driving it to rotate; the upper end of the distribution pipe 6 is rotatably connected to a spray pipe 8, one side of the spray pipe 8 is fixedly connected to a fixed cylinder 9 tangentially arranged therewith, the middle part of the upper end of the fixed cylinder 9 is fixedly connected to a feed pipe 12, and the upper end of the feed pipe 12 is fixedly connected to a feeding hopper 14, and alumina fiber bulk cotton in a lump shape is fed through the feeding hopper 14, and the alumina fiber bulk cotton falls into the arc-shaped grid plate 13 in the fixed cylinder 9 through the feed pipe 12;

[0055] See also Figure 5 and Figure 7The inner wall of the fixed cylinder 9 is fixedly connected with an arc-shaped grid plate 13 located below the connecting position between the feeding tube 12 and the fixed cylinder 9. A plurality of grid holes 1301 are provided on the arc-shaped grid plate 13. A comb-tooth roller 10 is rotatably connected in the fixed cylinder 9. The comb-tooth roller 10 is fixedly connected with the output shaft of the third motor 11. A plurality of comb-tooth rods 1001 cooperating with the grid holes 1301 are fixedly connected to the comb-tooth roller 10. When the third motor 11 drives the comb-tooth roller 10 to rotate, the comb-tooth rods 1001 rotate and pass through the grid holes 1301. The comb-tooth rods 1001 pull the alumina fiber loose cotton in the form of lumps that fall into the arc-shaped grid plate 13 to obtain a plurality of fiber strands in the form of long strips.

[0056] See also Fig. 9 The upper end of the blowing tube 8 is connected to the external high-pressure air pump through the air inlet pipe 15, and the external high-pressure air pump injects the high-pressure airflow into the blowing tube 8. When the comb rod 1001 drives the long-shaped multi-strand fiber filaments to move into the blowing tube 8, the high-pressure airflow blows the long-shaped multi-strand fiber filaments at high speed, so that the long-shaped multi-strand fiber filaments are separated from the comb rod 1001 and enter the distribution tube 6. At the same time, the high-pressure airflow causes the long-shaped multi-strand fiber filaments that fall into the distribution tube 6 to be blown away, and a plurality of independent single-strand fiber filaments are obtained, which are then discharged from the lower end opening of the distribution tube 6 under the action of the airflow, and float to the curtain-shaped slurry liquid film on the inner wall of the guide tube 2 to mix with the prefabricated emulsion.

[0057] Compared with the traditional preparation process of aluminum oxide fiberboard, when the prefabricated emulsion and oxidized fiber loose cotton are mixed, the present invention uses the guide cylinder 2 and the guide plate 3 arranged above the mixing impeller 4 to make the prefabricated emulsion flow upward along the annular cavity outside the guide cylinder 2 and flow back downward along the inner wall of the guide cylinder 2, so as to realize the circulation of the prefabricated emulsion and form a curtain-like liquid film on the inner wall of the guide cylinder 2 when flowing back downward; at the same time, with the rotatable distribution pipe 6, the aluminum oxide fiber filaments are fully contacted with the circulating prefabricated emulsion spread in the shape of a curtain, so as to improve the uniformity of the dispersion of the oxidized fiber filaments in the prefabricated emulsion; in addition, by arranging The comb roller 10 and the arc-shaped grid plate 13 in the fixed cylinder 9 cooperate with each other to comb the alumina fiber loose cotton in a mass into multiple fiber strands in a long strip shape, and through the tangentially connected blowing pipe 8 and the fixed cylinder 9, the high-pressure airflow is used to blow and separate the multiple fiber strands in a long strip shape, so that the multiple fiber strands are blown into single fiber strands before mixing with the prefabricated emulsion, further improving the mixing effect, reducing the probability of the alumina fiber strands flocculating into agglomerates in the prefabricated emulsion, further improving the uniformity of the dispersion of the alumina fiber strands in the prefabricated emulsion, improving the uniformity of the fiber slurry, and improving the subsequent molding quality of the alumina fiberboard.

[0058] It should be noted that in step one, the input ratio of nano-alumina, nano-zirconium oxide, silicon carbide, silicone resin and water is controlled so that the solid content of the prefabricated emulsion is 50%-70%; in step two, when preparing the fiber slurry, the input mass ratio of the prefabricated emulsion and the alumina fiber bulk cotton is made to be one to one; in step four, the curing temperature is 130°C-230°C; in step five, the calcination temperature is 800°C-1200°C, and the calcination time is 5H-8H; the alumina fiber bulk cotton is alumina polycrystalline fiber bulk cotton.

[0059] See also Figure 3 The guide cylinder 2 is a cylindrical structure that is vertically arranged and opened at both ends. An inwardly inclined annular guide surface 201 is provided at the upper end of the guide cylinder 2. The height of the opening position at the lower end of the fabric pipe 6 is set lower than the height of the annular guide surface 201.

[0060] Specifically, the prefabricated emulsion that moves along the annular cavity to the upper part of the guide cylinder 2 first flows onto the annular guide surface 201 under the action of the guide plate 3, making it easier for the prefabricated emulsion to spread on the inner wall of the guide cylinder 2 to form a curtain-like emulsion film with uniform thickness, further improving the mixing uniformity of the alumina fiber filaments and the prefabricated emulsion.

[0061] See also Figure 3 The part of the guide plate 3 facing the guide cylinder 2 extends to the annular guide surface 201, the guide plate 3 is tangent to the inner wall of the guide cylinder 2 in space, and multiple guide plates 3 are distributed on the upper end of the guide cylinder 2 at equal distances around the circumference.

[0062] Specifically, the plurality of guide plates 3 equidistantly distributed around the circumference and in contact with the annular guide surface 201 allow the prefabricated emulsion to be evenly dispersed on the annular guide surface 201 , further improving the uniformity of the emulsion film formation.

[0063] See also Figure 4 The first driving mechanism 5 includes a vertical shaft fixedly connected to the mixing impeller 4 and extending to the bottom of the mixing drum 1, and the vertical shaft is connected to the output shaft of the first motor through a transmission belt; the second driving mechanism 7 includes a second motor fixedly connected to the mixing drum 1, and the output shaft of the second motor is connected to the distribution pipe 6 through a transmission gear set.

[0064] Specifically, the first motor drives the vertical shaft to rotate through the transmission belt, and the vertical shaft drives the mixing impeller 4 to rotate, so as to centrifugally stir the prefabricated emulsion in the mixing cylinder 1, so that the emulsion rises along the annular cavity to the top of the guide cylinder 2, and then flows downward along the inner wall of the guide cylinder 2 to the position of the mixing impeller 4; the second motor drives the distribution tube 6 to rotate through the transmission gear set, and the distribution tube 6 makes a circular motion to spray the single fiber filament onto the flowing emulsion liquid film on the inner wall of the guide cylinder 2.

[0065] See also Figure 7 and Figure 8 The blowing tube 8 is a square tube with a rectangular cross section, the fixed tube 9 is a longitudinally arranged cylindrical structure, the fixed tube 9 is fixedly connected to the mixing tube 1 through the mounting plate 16, the arc grille plate 13 is a strip plate with an arc cross section, the grille holes 1301 are arranged along the bending direction of the arc grille plate 13, and the comb tooth rod 1001 is a cylindrical rod.

[0066] Specifically, the arc-shaped grid plate 13 and the inner walls on both sides of the fixing tube 9 are enclosed to form an arc-shaped cavity, and the arc-shaped cavity is communicated with the discharge pipe 12 .

[0067] Second implementation method:

[0068] Figure 11-14 A preparation process of an alumina composite fiber board is shown. On the basis of the first embodiment, a deflocculation mechanism is provided at the lower part of the mixing barrel 1. The deflocculation mechanism includes a plurality of groups of movable pins 17 which are circumferentially distributed and nested in the shell wall of the mixing barrel 1. The movable pins 17 are sleeved with springs 18 which enable them to be received in the shell wall of the mixing barrel 1 when not subjected to external force. A fourth driving mechanism for driving the movable pins 17 to extend into the inner cavity of the mixing barrel 1 is installed in the shell wall of the mixing barrel 1. The fourth driving mechanism periodically pushes the movable pins 17 to be inserted into the inner cavity of the mixing barrel 1. Rotating pins 22 which are arranged in an interlaced distribution relative to the movable pins 17 are fixedly connected to the outer wall of the mixing impeller 4.

[0069] Specifically, the fourth driving mechanism periodically pushes the movable pin 17 from the inner wall of the mixing barrel 1 to the inner cavity of the mixing barrel 1. Under the centrifugal driving force of the mixing impeller 4, the fiber slurry mixed with the alumina fiber and the prefabricated emulsion is pushed to the inner wall of the mixing barrel 1 where the movable pin 17 is located. When there are lumps of fiber flocs in the fiber slurry, the fiber flocs will be penetrated and captured by the extended movable pin 17 under the action of centrifugal force. At the same time, the mixing impeller 4 drives the rotating pins 22 staggered with the movable pins 17 to make circular motion. The rotating pins 22 pull and tear the fiber flocs penetrated and captured by the movable pins 17, so that the fiber flocs are torn, thereby realizing the removal of the fiber flocs in the fiber slurry.

[0070] See also Fig.11 A clamping cavity 101 is provided at the lower part of the mixing cylinder 1, and evenly distributed horizontal holes 102 are provided on the inner side of the clamping cavity 101 of the mixing cylinder 1. A movable pin 17 is slidably nested in the horizontal hole 102 and extends into the clamping cavity 101. The movable pin 17 is a horizontal rod with a spherical end and a needle-shaped end, and the needle-shaped end faces the inner cavity of the mixing cylinder 1. The fourth driving mechanism includes an extrusion ring 20 slidably nested in the clamping cavity 101 and a lifting mechanism for driving the extrusion ring 20 to move up and down.

[0071] For details, please refer to Fig.14When the lifting mechanism drives the extrusion ring 20 to move downward, the extrusion ring 20 squeezes the spherical end of the movable pin 17, so that the spring 18 is compressed and the movable pin 17 is inserted into the inner cavity of the mixing cylinder 1; when the lifting mechanism drives the extrusion ring 20 to move upward, the extrusion ring 20 is separated from the movable pin 17, and the spring 18 pushes the movable pin 17 back to the initial position and is re-stored inside the horizontal hole 102;

[0072] It should be noted that the fourth driving mechanism is periodically started to prevent the single fiber strand from being blocked by the movable pin 17 and then being entangled and agglomerated on the movable pin 17 .

[0073] See also Figure 1 The extrusion ring 20 is a circular ring with an inverted L-shaped cross section, and an extrusion slope 2001 is provided on the lower edge of the extrusion ring 20.

[0074] Specifically, when the extrusion ring 20 moves downward, the spherical end of the movable pin 17 contacts the extrusion slope 2001, and the extrusion slope 2001 pushes the movable pin 17 to extend horizontally.

[0075] See also Fig.12 The lifting mechanism is one of an electric push rod 21 and a hydraulic telescopic cylinder.

[0076] Specifically, the movable end of the electric push rod 21 or the hydraulic telescopic cylinder is fixedly connected to the upper end surface of the extrusion ring 20 , and the inactive end of the electric push rod 21 or the hydraulic telescopic cylinder is fixedly connected to the top wall of the clamping cavity 101 .

[0077] See also Fig.11 and Fig.13 A sealing ring 19 is fixedly connected in the horizontal hole 102 and sleeved on the outside of the movable pin 17 . The sealing ring 19 is an annular sealing ring and has an interference fit with the movable pin 17 .

[0078] Specifically, the horizontal hole 102 is movably sealed by the provided sealing ring 19 to prevent the prefabricated emulsion from flowing into the clamping cavity 101 through the horizontal hole 102 .

[0079] In view of current practical needs, the above-mentioned implementation mode adopted in this application is not limited to the scope of protection. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the scope of protection of the present invention.

Claims

1. A process for preparing an alumina composite fiberboard, characterized in that: The steps include: Step 1, preparing slurry: putting nano-alumina, nano-zirconium oxide, silicon carbide, siloxane resin and water into a low-speed mixer for stirring and mixing to obtain a prefabricated emulsion; Step 2, preparing fiber slurry: putting the prefabricated emulsion obtained in step 1 and alumina fiber loose cotton into a high-speed mixer for stirring to obtain fiber slurry; Step three, adjusting the water content; transferring the fiber slurry from step two to a precision filter, and adjusting the water content of the fiber slurry as needed to obtain a dehydrated fiber slurry; Step 4, curing: transferring the dehydrated fiber slurry obtained in step 3 to a forming mold, extruding and curing it, and then heating and curing it, and demolding it to obtain a cured fiberboard; Step five, calcination; The cured fiberboard obtained in step 4 is transferred to a calcining furnace for calcination to obtain a calcined fiberboard; Step 6, cooling and cutting: taking out the calcined fiberboard obtained in step 5 from the calcining furnace and cooling it, and then cutting and shaping it according to production needs to obtain a finished alumina fiberboard; The high-speed mixer comprises a mixing drum (1), a guide drum (2) is arranged inside the mixing drum (1), an annular cavity is formed between the outer wall of the guide drum (2) and the inner wall of the mixing drum (1), a plurality of guide plates (3) are fixedly connected to the upper end of the guide drum (2) and are spanning the annular cavity and are fixedly connected to the inner wall of the mixing drum (1); a mixing impeller (4) is arranged below the guide drum (2), and the mixing impeller (4) is connected to a first driving mechanism (5) for driving the mixing impeller to rotate; A distribution pipe (6) rotatably connected to the top plate of the mixing cylinder (1) is provided at the center of the upper part of the guide cylinder (2); the distribution pipe (6) is L-shaped and the lower end opening faces the inner wall of the guide cylinder (2); the upper part of the distribution pipe (6) is connected to a second driving mechanism (7) for driving the distribution pipe (6) to rotate; the upper end of the distribution pipe (6) is rotatably connected to a blowing pipe (8); one side of the blowing pipe (8) is fixedly connected to a fixed cylinder (9) tangentially arranged therewith; the middle part of the upper end of the fixed cylinder (9) is fixedly connected to a feeding pipe (12); the upper end of the feeding pipe (12) is fixedly connected to a feeding hopper (14); The inner wall of the fixed cylinder (9) is fixedly connected with an arc-shaped grid plate (13) located below the connecting position between the feeding tube (12) and the fixed cylinder (9); a plurality of grid holes (1301) are provided on the arc-shaped grid plate (13); a comb-tooth roller (10) is rotatably connected inside the fixed cylinder (9); the comb-tooth roller (10) is fixedly connected with the output shaft of the third motor (11); and a plurality of groups of comb-tooth rods (1001) matching with the grid holes (1301) are fixedly connected to the comb-tooth roller (10); the upper end of the blowing pipe (8) is connected with an external high-pressure air pump through an air inlet pipe (15).

2. The process for preparing an alumina composite fiberboard according to claim 1, characterized in that: The mixing cylinder (1) is provided with a flocculent removal mechanism at the bottom thereof, the flocculent removal mechanism comprising a plurality of groups of movable pins (17) which are distributed in a circumferential manner and are nested in the shell wall of the mixing cylinder (1), the movable pins (17) being sleeved with springs (18) which enable the movable pins (17) to be received in the shell wall of the mixing cylinder (1) when not subjected to external force, a fourth driving mechanism which drives the movable pins (17) to extend into the inner cavity of the mixing cylinder (1) is installed in the shell wall of the mixing cylinder (1), the fourth driving mechanism periodically drives the movable pins (17) to be inserted into the inner cavity of the mixing cylinder (1), and rotating pins (22) which are arranged in a staggered distribution opposite to the movable pins (17) are fixedly connected to the outer wall of the mixing impeller (4).

3. The process for preparing an alumina composite fiberboard according to claim 1, characterized in that: The guide cylinder (2) is a cylindrical structure which is vertically arranged and has openings at both ends. The upper end of the guide cylinder (2) is provided with an annular flow guide surface (201) which is inclined inwards. The opening position at the lower end of the material distribution pipe (6) is arranged at a height lower than the height of the annular flow guide surface (201).

4. The process for preparing an alumina composite fiberboard according to claim 1, characterized in that: The portion of the guide plate (3) facing the side of the guide cylinder (2) extends to the annular guide surface (201), the guide plate (3) and the inner wall of the guide cylinder (2) are spatially tangent, and a plurality of guide plates (3) are equidistantly distributed on the upper end of the guide cylinder (2) in a circumferential manner.

5. The process for preparing an alumina composite fiberboard according to claim 1, characterized in that: The first driving mechanism (5) comprises a vertical shaft fixedly connected to the mixing impeller (4) and extending to the bottom of the mixing drum (1), the vertical shaft being connected to the output shaft of the first motor via a transmission belt; the second driving mechanism (7) comprises a second motor fixedly connected to the mixing drum (1), the output shaft of the second motor being connected to the material distribution pipe (6) via a transmission gear set for transmission.

6. The process for preparing an alumina composite fiberboard according to claim 1, characterized in that: The blowing pipe (8) is a square tube with a rectangular cross section, the fixed cylinder (9) is a longitudinally arranged cylindrical structure, the fixed cylinder (9) is fixedly connected to the mixing cylinder (1) via a mounting plate (16), the arc-shaped grid plate (13) is a strip plate with an arc-shaped cross section, the grid holes (1301) are arranged along the bending direction of the arc-shaped grid plate (13), and the comb tooth rod (1001) is a cylindrical rod.

7. The process for preparing an alumina composite fiberboard according to claim 2, characterized in that: The mixing cylinder (1) has a clamping cavity (101) at its lower part, and the mixing cylinder (1) has uniformly distributed horizontal holes (102) located inside the clamping cavity (101). A movable pin (17) is slidably nested in the horizontal hole (102) and extends into the clamping cavity (101). The movable pin (17) is a horizontal rod with a spherical end and a needle-shaped end, and the needle-shaped end faces the inner cavity of the mixing cylinder (1). The fourth driving mechanism comprises an extrusion ring (20) slidably nested in the clamping cavity (101) and a lifting mechanism for driving the extrusion ring (20) to move up and down.

8. The process for preparing an alumina composite fiber board according to claim 7, characterized in that: The extrusion ring (20) is a circular ring with an inverted L-shaped cross section, and an extrusion slope (2001) is provided on the lower edge of the extrusion ring (20).

9. The process for preparing an alumina composite fiberboard according to claim 7, characterized in that: The lifting mechanism is one of an electric push rod (21) and a hydraulic telescopic cylinder.

10. The process for preparing an alumina composite fiber board according to claim 7, characterized in that: A sealing ring (19) sleeved on the outside of the movable pin (17) is fixedly connected in the horizontal hole (102); the sealing ring (19) is an annular sealing ring and is interference-fitted with the movable pin (17).

Images