A preparation method of high-strength thermal insulation calcium silicate material

Abstract

The present invention discloses a method for preparing a high-strength thermal insulation calcium silicate material, comprising: preparing a pre-slurry using deionized water, ceramic fiber and silica powder; adding silica aerogel and a foaming agent to the pre-slurry for dispersion treatment to prepare a silica aerogel slurry; using a calcareous raw material and the silica aerogel slurry, adding reinforcing fiber, zeolite powder and a waterproofing agent for hydrothermal reaction to prepare microporous calcium silicate particles; preparing a calcium silicate aluminum silicate slurry from the microporous calcium silicate particles and aluminum silicate fiber; vacuum filtering the calcium silicate aluminum silicate slurry to obtain a high-strength thermal insulation calcium silicate material. The present invention successfully prepares a calcium silicate material with high strength and excellent thermal insulation performance by optimizing the formula, introducing silica aerogel and a foaming agent, and adopting a hydrothermal reaction. The prepared calcium silicate insulation product has superior properties such as light weight, low thermal conductivity and high compressive strength.

Description

Technical Field

[0001] The present invention relates to the technical field of calcium silicate materials, and in particular to a method for preparing a high-strength thermal insulation calcium silicate material. Background Art

[0002] Calcium silicate insulation products are widely used as thermal insulation materials for high-temperature equipment. They offer advantages such as light weight, low thermal conductivity, high compressive strength, and high operating temperatures. However, their practical application presents a series of technical challenges. Currently, the main issue is that calcium silicate insulation products are prone to cracking, which impairs their effectiveness and further limits their widespread application.

[0003] Traditional calcium silicate insulation products suffer from complex production processes, significant raw material waste, and high production costs, resulting in expensive products that are difficult for users to accept. Most manufacturers produce standard 220-grade calcium silicate insulation products, with a few producing 170-grade hydrophobic products. However, these products struggle to meet export quality and variety requirements. Standard 220-grade products are prone to cracking during use, hindering their effectiveness and further application. Some manufacturers have attempted to produce 220- and 170-grade, high-temperature-resistant xonotlite-based calcium silicate insulation products, primarily for high-temperature equipment insulation, but have yet to successfully produce ultra-lightweight, hydrophobic calcium silicate insulation products.

[0004] In addition, traditional insulation methods, such as aluminum silicate wool, rock wool, calcium silicate board, etc., have some common problems, such as different thermal expansion coefficients leading to breakage, and the insulation effect of fiber wool decreasing after absorbing water. These problems seriously restrict the performance and application range of insulation materials.

[0005] In summary, traditional calcium silicate insulation products face numerous challenges in practical applications, including cracking, high production costs, and limited application. To address these technical issues, the present invention proposes a method for preparing a high-strength insulating calcium silicate material. This approach aims to provide a more advanced, superior, and economical calcium silicate insulation product that meets the insulation and heat preservation needs of industrial high-temperature equipment while maintaining strength. Summary of the Invention

[0006] The object of the present invention is to provide a method for preparing a high-strength insulating calcium silicate material to solve at least one of the above-mentioned technical problems. By optimizing the formula, introducing silica aerogel and a foaming agent, and adopting key steps such as hydrothermal reaction, a calcium silicate material with high strength and excellent thermal insulation performance is successfully prepared. The prepared calcium silicate insulation products have superior properties such as light weight, low thermal conductivity, and high compressive strength, providing a more advanced and economical solution for thermal insulation of industrial high-temperature equipment.

[0007] The embodiment of the present invention is achieved as follows:

[0008] A method for preparing a high-strength thermal insulating calcium silicate material, comprising:

[0009] S100, using deionized water, ceramic fiber and silica powder to prepare a pre-slurry;

[0010] S200, adding silica aerogel and a foaming agent to the pre-slurry for dispersion treatment to prepare silica aerogel slurry;

[0011] S300, using a calcium raw material and the silica aerogel slurry, adding reinforcing fiber, zeolite powder and a waterproofing agent to carry out a hydrothermal reaction to prepare microporous calcium silicate particles;

[0012] S400, preparing a calcium silicate aluminum silicate slurry by combining the microporous calcium silicate particles and aluminum silicate fibers;

[0013] S500, vacuum filtering the calcium silicate aluminum silicate slurry to obtain a high-strength thermal insulation calcium silicate material.

[0014] In a preferred embodiment of the present invention, in S100 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of preparing a pre-slurry using deionized water, ceramic fiber and silica powder includes:

[0015] S101, taking the raw materials according to the mass ratio of deionized water: ceramic fiber: silica powder = (65-75): (20-30): (15-25);

[0016] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0017] After adding deionized water and ceramic fibers, immerse them in the mixing barrel to about 2 / 3 of the capacity. By controlling the speed of the high-speed disperser, the ceramic fibers can be prevented from agglomerating when they come into contact with water.

[0018] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0019] After the silica powder is added, the rotation speed is appropriately increased to make the solution have a certain viscosity, while ensuring that the slurry is evenly dispersed to obtain the pre-slurry.

[0020] Its technical effect is: by using a high-speed disperser for stirring and accurately controlling the rotation speed, the agglomeration of ceramic fibers in water can be effectively avoided, and each component can be evenly dispersed in the slurry without adhesion and precipitation, so that the viscosity of the slurry can be controlled and the slurry can be evenly dispersed.

[0021] In a preferred embodiment of the present invention, in S200 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of adding silica aerogel and a foaming agent to the pre-slurry for dispersion treatment to prepare the silica aerogel slurry includes:

[0022] S201, taking the raw materials, adding the pre-slurry and the foaming agent into a stirring barrel in a mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = (55-65): (25-35): (10-20): (0-30);

[0023] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0024] At this time, the rotation speed cannot be too fast. The density of silica aerogel is very small and it is very easy to fly away during the mixing process. It is best not to add more than 20g each time to reduce the loss of silica aerogel.

[0025] The technical effect is that: adding silica aerogel while stirring with a high-speed disperser can effectively prevent the silica aerogel from scattering due to volume reduction and control its loss.

[0026] In a preferred embodiment of the present invention, the method for preparing the high-strength thermal insulating calcium silicate material further comprises:

[0027] S203, if the slurry solidifies during stirring, add deionized water.

[0028] The technical effect is that as silica aerogel is added, the slurry will become drier and drier until the slurry solidifies. Therefore, some deionized water can be added appropriately during this process to keep the fluidity of the slurry at all times.

[0029] In a preferred embodiment of the present invention, in S300 of the method for preparing the high-strength thermally insulating calcium silicate material, the steps of using a calcium raw material and the silica aerogel slurry, adding reinforcing fiber, zeolite powder and a waterproofing agent to carry out a hydrothermal reaction to prepare microporous calcium silicate particles include:

[0030] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0031] S302, taking the raw materials in the mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = (53-68): (23-27): (2-6): (0.8-5): (0.5-3);

[0032] Among them, the chemical components of quicklime include calcium oxide, silicon dioxide, iron oxide, aluminum oxide, magnesium oxide, etc., of which calcium oxide accounts for about 85% by mass and silicon dioxide accounts for about 1%.

[0033] Reinforcement fibers are used to improve the strength and toughness of materials. Their chemical compositions include glass fiber, carbon fiber, polypropylene fiber, etc. and their mixtures.

[0034] Zeolite is a natural mineral with a microporous structure. Zeolite powder includes the main components of zeolite minerals, such as aluminum oxide, silicon, etc. and their mixtures.

[0035] Waterproofing agents are used to improve the waterproof properties of materials, including silicone waterproofing agents, polymer emulsion waterproofing agents, etc. and their mixtures.

[0036] S303, mixing the raw materials, stirring at a temperature range of 205-225° C. and a pressure range of 1.7-2.4 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0037] The technical benefits of this method lie in its use of a static production process, leveraging the properties of gelation to prevent the reaction raw materials from settling during the static hydrothermal synthesis process. The strong chemical affinity between the organosilicon compound and the inorganic silicate material effectively alters the surface properties of the silicate material, resulting in a calcium silicate material with more pores and loose inter-granular bonding, resulting in well-grown crystal particles and a high porosity.

[0038] Nanosilicon has high purity, small particle size, uniform distribution, and a large surface area, resulting in high surface activity. This high surface activity accelerates the production of calcium silicate insulation products. These products offer high strength, strong flexural and compressive resistance, high temperature resistance, excellent thermal insulation, low thermal conductivity, and reduced heat loss, making them suitable for the processing and production of various precision parts.

[0039] In a preferred embodiment of the present invention, in S400 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of preparing the microporous calcium silicate particles and aluminum silicate fibers to obtain a calcium silicate aluminum silicate slurry includes:

[0040] S401, taking the raw materials according to the mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = (35-55): (35-55): (1-3): (10-20);

[0041] S402, using a high-speed roller press to mix the raw materials at a speed of 4000-8000 r / min for 15-30 min to obtain calcium silicate aluminum silicate slurry.

[0042] The technical effect is that the components are fully mixed, and high-speed and efficient mixing can make solid materials such as microporous calcium silicate particles and aluminum silicate fibers uniformly dispersed and chopped, and with an appropriate amount of silica adhesive, a viscous and uniform calcium silicate aluminum silicate slurry is formed.

[0043] In a preferred embodiment of the present invention, in S401 of the method for preparing the high-strength thermal insulating calcium silicate material, the aluminum silicate fibers have a length of 6 to 25 mm and are produced by chopping the aluminum silicate fibers using a multi-axis vibrating machine.

[0044] The technical effect lies in controlling the length of aluminum silicate fibers. Excessive length will affect mixing uniformity, while too short will not be conducive to the formation of a three-dimensional network structure. After chopped fibers, the fiber length specification is within the control range, which is conducive to uniform distribution in the slurry, sufficient mixing and bonding, and providing structural support for subsequent molding. Using a multi-axis vibration machine for chopped fibers has a better shearing effect than single-axis operation, which can effectively avoid fiber kinking and entanglement during the cutting process, and can cut aluminum silicate fibers into appropriate lengths more quickly and accurately.

[0045] In a preferred embodiment of the present invention, in S500 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of vacuum filtering the calcium silicate and aluminum silicate slurry to obtain the high-strength thermal insulating calcium silicate material includes:

[0046] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0047] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0048] The technical effect is that the aluminum silicate ceramic fiber layer is formed on the filtration mesh plate within the vacuum filtration chamber, which can filter and fix the particles and fibers in the slurry, forming a stable base. By re-preparing the vacuum filtration chamber and placing the aluminum silicate ceramic fiber layer, the calcium silicate aluminum silicate slurry is vacuum filtered. The aluminum silicate ceramic fiber layer on the filtration mesh plate filters out excess liquid and solid particles, thereby obtaining a high-strength thermal insulation calcium silicate material.

[0049] In a preferred embodiment of the present invention, in S501 of the preparation method of the above-mentioned high-strength insulating calcium silicate material, the pore size of the filtration mesh is 5 to 20 μm, the mesh thickness is 1 to 5 mm, the vacuum degree is 120 to 200 Pa, the filtration time is 12 to 20 min, and the injection rate of the slurry is 0.3 to 0.8 mL / min.

[0050] In a preferred embodiment of the present invention, in S502 of the preparation method of the above-mentioned high-strength insulating calcium silicate material, the pore size of the filtration mesh is 5 to 20 μm, the mesh thickness is 1 to 5 mm, the vacuum degree is 120 to 200 Pa, the filtration time is 25 to 32 min, and the injection rate of the slurry is 0.3 to 0.8 mL / min.

[0051] The technical benefits are as follows: the pore size of the filtration screen effectively captures and supports particles in the slurry, evenly distributing them to form a structure; the thickness of the screen combined with the appropriate pore size ensures fluidity and support strength; the vacuum level provides a sufficient vacuum environment to assist filtration; the filtration time has been proven to produce a formed body of sufficient consistency; and the slurry injection rate prevents excessive pressure differences from affecting filtration while ensuring sufficient slurry loss. By optimizing the matching of these parameters, the filtration rate and efficiency can be improved, and the slurry components can be evenly distributed and arranged, forming a compact structure. The final product has high strength, high density, and a regular structure.

[0052] The beneficial effects of the embodiments of the present invention are:

[0053] In the preparation of silica aerogel, the method of adding silica aerogel while stirring with a high-speed disperser is adopted, which effectively prevents the dispersion of silica aerogel due to volume reduction, thereby controlling its loss. By using a high-speed disperser for stirring and precisely controlling the speed, the agglomeration of ceramic fibers in water is avoided, ensuring that the components in the slurry are evenly dispersed, without adhesion and precipitation, and the slurry viscosity is controlled to ensure uniform dispersion of the slurry. In case the slurry may solidify during the preparation process, the step of adding deionized water is introduced to ensure that the slurry always maintains a certain level of fluidity, which facilitates the subsequent process.

[0054] The present invention utilizes a static production process, combined with the characteristics of gelation, to prevent the calcium silicate particles from settling during the hydrothermal synthesis process. This results in a calcium silicate material with numerous pores and loose intergranular bonds, thereby increasing the material's porosity. The calcium silicate particles and aluminum silicate fibers are mixed using a high-speed roller press, ensuring that all components are evenly dispersed and chopped, forming a viscous and uniform calcium silicate / aluminum silicate slurry.

[0055] In the preparation of aluminum silicate fibers, a multi-axis vibrating machine is used for short-cutting, which controls the fiber length and facilitates uniform distribution within the slurry, thorough mixing and bonding, and provides structural support for subsequent molding. The filtration screen within the vacuum filtration chamber filters and secures the particles and fibers in the slurry, forming a stable substrate. By re-preparing the vacuum filtration chamber and placing a layer of aluminum silicate ceramic fibers, vacuum filtration is repeated, ultimately resulting in a high-strength, thermally insulating calcium silicate material. By optimizing the filtration screen's aperture, thickness, vacuum level, filtration time, and slurry injection speed, the filtration rate and efficiency are improved, helping to evenly distribute and arrange the slurry components, forming a compact structure. The resulting finished product exhibits excellent properties such as high strength, high density, and a regular structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0057] Figure 1 The figure is a schematic flow chart of the preparation method of the high-strength thermal insulating calcium silicate material of the present invention. DETAILED DESCRIPTION

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0059] Please refer to Figure 1 The first embodiment of the present invention provides a method for preparing a high-strength thermal insulating calcium silicate material, which comprises:

[0060] S100, using deionized water, ceramic fiber and silica powder to prepare a pre-slurry;

[0061] S200, adding silica aerogel and a foaming agent to the pre-slurry for dispersion treatment to prepare silica aerogel slurry;

[0062] S300, using a calcium raw material and the silica aerogel slurry, adding reinforcing fiber, zeolite powder and a waterproofing agent to carry out a hydrothermal reaction to prepare microporous calcium silicate particles;

[0063] S400, preparing a calcium silicate aluminum silicate slurry by combining the microporous calcium silicate particles and aluminum silicate fibers;

[0064] S500, vacuum filtering the calcium silicate aluminum silicate slurry to obtain a high-strength thermal insulation calcium silicate material.

[0065] In a preferred embodiment of the present invention, in S100 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of preparing a pre-slurry using deionized water, ceramic fiber and silica powder includes:

[0066] S101, taking the raw materials according to the mass ratio of deionized water: ceramic fiber: silica powder = (65-75): (20-30): (15-25);

[0067] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0068] After adding deionized water and ceramic fibers, immerse them in the mixing barrel to about 2 / 3 of the capacity. By controlling the speed of the high-speed disperser, the ceramic fibers can be prevented from agglomerating when they come into contact with water.

[0069] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0070] After the silica powder is added, the rotation speed is appropriately increased to make the solution have a certain viscosity, while ensuring that the slurry is evenly dispersed to obtain the pre-slurry.

[0071] Its technical effect is: by using a high-speed disperser for stirring and accurately controlling the rotation speed, the agglomeration of ceramic fibers in water can be effectively avoided, and each component can be evenly dispersed in the slurry without adhesion and precipitation, so that the viscosity of the slurry can be controlled and the slurry can be evenly dispersed.

[0072] In a preferred embodiment of the present invention, in S200 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of adding silica aerogel and a foaming agent to the pre-slurry for dispersion treatment to prepare the silica aerogel slurry includes:

[0073] S201, taking the raw materials, adding the pre-slurry and the foaming agent into a stirring barrel in a mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = (55-65): (25-35): (10-20): (0-30);

[0074] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0075] At this time, the rotation speed cannot be too fast. The density of silica aerogel is very small and it is very easy to fly away during the mixing process. It is best not to add more than 20g each time to reduce the loss of silica aerogel.

[0076] The technical effect is that: adding silica aerogel while stirring with a high-speed disperser can effectively prevent the silica aerogel from scattering due to volume reduction and control its loss.

[0077] In a preferred embodiment of the present invention, the method for preparing the high-strength thermal insulating calcium silicate material further comprises:

[0078] S203, if the slurry solidifies during stirring, add deionized water.

[0079] The technical effect is that as silica aerogel is added, the slurry will become drier and drier until the slurry solidifies. Therefore, some deionized water can be added appropriately during this process to keep the fluidity of the slurry at all times.

[0080] In a preferred embodiment of the present invention, in S300 of the method for preparing the high-strength thermally insulating calcium silicate material, the steps of using a calcium raw material and the silica aerogel slurry, adding reinforcing fiber, zeolite powder and a waterproofing agent to carry out a hydrothermal reaction to prepare microporous calcium silicate particles include:

[0081] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0082] S302, taking the raw materials in the mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = (53-68): (23-27): (2-6): (0.8-5): (0.5-3);

[0083] Among them, the chemical components of quicklime include calcium oxide, silicon dioxide, iron oxide, aluminum oxide, magnesium oxide, etc., of which calcium oxide accounts for about 85% by mass and silicon dioxide accounts for about 1%.

[0084] Reinforcement fibers are used to improve the strength and toughness of materials. Their chemical compositions include glass fiber, carbon fiber, polypropylene fiber, etc. and their mixtures.

[0085] Zeolite is a natural mineral with a microporous structure. Zeolite powder includes the main components of zeolite minerals, such as aluminum oxide, silicon, etc. and their mixtures.

[0086] Waterproofing agents are used to improve the waterproof properties of materials, including silicone waterproofing agents, polymer emulsion waterproofing agents, etc. and their mixtures.

[0087] S303, mixing the raw materials, stirring at a temperature range of 205-225° C. and a pressure range of 1.7-2.4 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0088] The technical benefits of this method lie in its use of a static production process, leveraging the properties of gelation to prevent the reaction raw materials from settling during the static hydrothermal synthesis process. The strong chemical affinity between the organosilicon compound and the inorganic silicate material effectively alters the surface properties of the silicate material, resulting in a calcium silicate material with more pores and loose inter-granular bonding, resulting in well-grown crystal particles and a high porosity.

[0089] Nanosilicon has high purity, small particle size, uniform distribution, and a large surface area, resulting in high surface activity. This high surface activity accelerates the production of calcium silicate insulation products. These products offer high strength, strong flexural and compressive resistance, high temperature resistance, excellent thermal insulation, low thermal conductivity, and reduced heat loss, making them suitable for the processing and production of various precision parts.

[0090] In a preferred embodiment of the present invention, in S400 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of preparing the microporous calcium silicate particles and aluminum silicate fibers to obtain a calcium silicate aluminum silicate slurry includes:

[0091] S401, taking the raw materials according to the mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = (35-55): (35-55): (1-3): (10-20);

[0092] S402, using a high-speed roller press to mix the raw materials at a speed of 4000-8000 r / min for a time range of 15-30 min to obtain calcium silicate aluminum silicate slurry.

[0093] The technical effect is that the components are fully mixed, and high-speed and efficient mixing can make solid materials such as microporous calcium silicate particles and aluminum silicate fibers uniformly dispersed and chopped, and with an appropriate amount of silica adhesive, a viscous and uniform calcium silicate aluminum silicate slurry is formed.

[0094] In a preferred embodiment of the present invention, in S401 of the method for preparing the high-strength thermal insulating calcium silicate material, the aluminum silicate fibers have a length of 6 to 25 mm and are produced by chopping the aluminum silicate fibers using a multi-axis vibrating machine.

[0095] The technical effect lies in controlling the length of aluminum silicate fibers. Excessive length will affect mixing uniformity, while too short will not be conducive to the formation of a three-dimensional network structure. After chopped fibers, the fiber length specification is within the control range, which is conducive to uniform distribution in the slurry, sufficient mixing and bonding, and providing structural support for subsequent molding. Using a multi-axis vibration machine for chopped fibers has a better shearing effect than single-axis operation, which can effectively avoid fiber kinking and entanglement during the cutting process, and can cut aluminum silicate fibers into appropriate lengths more quickly and accurately.

[0096] In a preferred embodiment of the present invention, in S500 of the method for preparing the high-strength thermal insulating calcium silicate material, the step of vacuum filtering the calcium silicate and aluminum silicate slurry to obtain the high-strength thermal insulating calcium silicate material includes:

[0097] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0098] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0099] The technical effect is that the aluminum silicate ceramic fiber layer is formed on the filtration mesh plate within the vacuum filtration chamber, which can filter and fix the particles and fibers in the slurry, forming a stable base. By re-preparing the vacuum filtration chamber and placing the aluminum silicate ceramic fiber layer, the calcium silicate aluminum silicate slurry is vacuum filtered. The aluminum silicate ceramic fiber layer on the filtration mesh plate filters out excess liquid and solid particles, thereby obtaining a high-strength thermal insulation calcium silicate material.

[0100] In a preferred embodiment of the present invention, in S501 of the preparation method of the above-mentioned high-strength insulating calcium silicate material, the pore size of the filtration mesh is 5 to 20 μm, the mesh thickness is 1 to 5 mm, the vacuum degree is 120 to 200 Pa, the filtration time is 12 to 20 min, and the injection rate of the slurry is 0.3 to 0.8 mL / min.

[0101] In a preferred embodiment of the present invention, in S502 of the preparation method of the above-mentioned high-strength insulating calcium silicate material, the pore size of the filtration mesh is 5 to 20 μm, the mesh thickness is 1 to 5 mm, the vacuum degree is 120 to 200 Pa, the filtration time is 25 to 32 min, and the injection rate of the slurry is 0.3 to 0.8 mL / min.

[0102] The technical benefits are as follows: the pore size of the filtration screen effectively captures and supports particles in the slurry, evenly distributing them to form a structure; the thickness of the screen combined with the appropriate pore size ensures fluidity and support strength; the vacuum level provides a sufficient vacuum environment to assist filtration; the filtration time has been proven to produce a formed body of sufficient consistency; and the slurry injection rate prevents excessive pressure differences from affecting filtration while ensuring sufficient slurry loss. By optimizing the matching of these parameters, the filtration rate and efficiency can be improved, and the slurry components can be evenly distributed and arranged, forming a compact structure. The final product has high strength, high density, and a regular structure.

[0103] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0104] (1) Example 1:

[0105] A method for preparing a high-strength thermal insulating calcium silicate material, comprising:

[0106] S101, prepare the raw materials in a mass ratio of deionized water: ceramic fiber: silica powder = 69.2:26.8:19;

[0107] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0108] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0109] S201, taking the raw materials in a mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = 60:30:15:20, and adding the pre-slurry and foaming agent into a mixing barrel;

[0110] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0111] S203, if the slurry solidifies during stirring, add deionized water.

[0112] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0113] S302, taking the raw materials in the mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = 59:25:4.5:3.5:1.9;

[0114] S303, mixing the raw materials, stirring at a temperature of 215° C. and a pressure of 2 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0115] S401, preparing raw materials in a mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = 45:45:2:15;

[0116] S402, using a high-speed roller press to mix the raw materials at a speed of 6000 r / min for 22 minutes to obtain calcium silicate aluminum silicate slurry.

[0117] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0118] The pore size of the filtration mesh is 12 μm, the thickness of the mesh is 3 mm, the vacuum degree is 150 Pa, the filtration time is 16 min, and the injection speed of the slurry is 0.5 mL / min.

[0119] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0120] The pore size of the filtration mesh is 12 μm, the thickness of the mesh is 3 mm, the vacuum degree is 150 Pa, the filtration time is 28 min, and the injection speed of the slurry is 0.5 mL / min.

[0121] (II) Example 2:

[0122] S101, taking the raw materials in a mass ratio of deionized water: ceramic fiber: silica powder = 65:20:15;

[0123] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0124] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0125] S201, taking the raw materials in a mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = 55:25:10:5, and adding the pre-slurry and foaming agent into a mixing barrel;

[0126] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0127] S203, if the slurry solidifies during stirring, add deionized water.

[0128] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0129] S302, taking the raw materials in a mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = 53:23:2:0.8:0.5;

[0130] S303, mixing the raw materials, stirring at a temperature of 205° C. and a pressure of 1.7 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0131] S401, preparing the raw materials in a mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = 35:35:1:10;

[0132] S402, using a high-speed roller press to mix the raw materials at a speed of 4000 r / min for 15 minutes to obtain calcium silicate aluminum silicate slurry.

[0133] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0134] The pore size of the filtration mesh is 5 μm, the thickness of the mesh is 1 mm, the vacuum degree is 120 Pa, the filtration time is 12 min, and the injection speed of the slurry is 0.3 mL / min.

[0135] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0136] The pore size of the filtration mesh is 5 μm, the thickness of the mesh is 1 mm, the vacuum degree is 120 Pa, the filtration time is 25 min, and the injection speed of the slurry is 0.3 mL / min.

[0137] (III) Example 3:

[0138] S101, taking the raw materials in a mass ratio of deionized water: ceramic fiber: silica powder = 75:30:25;

[0139] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0140] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0141] S201, taking the raw materials according to the mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = 65:35:20:30, and adding the pre-slurry and foaming agent into a mixing barrel;

[0142] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0143] S203, if the slurry solidifies during stirring, add deionized water.

[0144] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0145] S302, taking the raw materials in a mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = 68:27:6:5:3;

[0146] S303, mixing the raw materials, stirring at a temperature of 225° C. and a pressure range of 2.4 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0147] S401, preparing the raw materials in a mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = 55:55:3:20;

[0148] S402, using a high-speed roller press to mix the raw materials at a speed of 8000 r / min for 30 minutes to obtain calcium silicate aluminum silicate slurry.

[0149] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0150] The pore size of the filtration mesh is 20 μm, the thickness of the mesh is 5 mm, the vacuum degree is 200 Pa, the filtration time is 20 min, and the injection speed of the slurry is 0.8 mL / min.

[0151] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0152] The pore size of the filtration mesh is 20 μm, the thickness of the mesh is 5 mm, the vacuum degree is 200 Pa, the filtration time is 32 min, and the injection speed of the slurry is 0.8 mL / min.

[0153] (IV) Example 4:

[0154] S101, taking the raw materials in a mass ratio of deionized water: ceramic fiber: silica powder = 66:22:16;

[0155] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0156] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0157] S201, taking the raw materials according to the mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = 56:26:12:5, and adding the pre-slurry and foaming agent into a mixing barrel;

[0158] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0159] S203, if the slurry solidifies during stirring, add deionized water.

[0160] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0161] S302, taking the raw materials in a mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = 55:24:3:1:0.8;

[0162] S303, mixing the raw materials, stirring at a temperature of 210° C. and a pressure of 1.8 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0163] S401, preparing raw materials in a mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silica adhesive: deionized water = 39:39:1.2:12;

[0164] S402, using a high-speed roller press to mix the raw materials at a speed of 4500 r / min for 18 minutes to obtain calcium silicate aluminum silicate slurry.

[0165] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0166] The pore size of the filtration mesh is 6 μm, the thickness of the mesh is 2 mm, the vacuum degree is 130 Pa, the filtration time is 13 min, and the injection speed of the slurry is 0.4 mL / min.

[0167] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0168] The pore size of the filtration mesh is 6 μm, the thickness of the mesh is 2 mm, the vacuum degree is 130 Pa, the filtration time is 26 min, and the injection speed of the slurry is 0.4 mL / min.

[0169] (V) Example 5:

[0170] S101, taking the raw materials in a mass ratio of deionized water: ceramic fiber: silica powder = 72:28:22;

[0171] S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes;

[0172] S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

[0173] S201, taking the raw materials according to the mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = 62:32:18:26, and adding the pre-slurry and foaming agent into a mixing barrel;

[0174] S202, while adding silica aerogel, stirring the mixing barrel using a high-speed disperser, maintaining the speed at 1000 r / min, to obtain a uniform silica aerogel slurry after 20 minutes;

[0175] S203, if the slurry solidifies during stirring, add deionized water.

[0176] S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200 mesh sieve;

[0177] S302, taking the raw materials in a mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = 63:26:5:4:2.6;

[0178] S303, mixing the raw materials, stirring at a temperature of 220° C. and a pressure of 2.2 MPa, and performing a hydrothermal reaction for more than 5 hours to obtain microporous calcium silicate particles.

[0179] S401, preparing raw materials in a mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = 50:50:2.5:18;

[0180] S402, using a high-speed roller press to mix the raw materials at a speed of 7500 r / min for 28 minutes to obtain calcium silicate aluminum silicate slurry.

[0181] S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use;

[0182] The pore size of the filtration mesh is 18 μm, the thickness of the mesh is 4 mm, the vacuum degree is 180 Pa, the filtration time is 18 min, and the injection speed of the slurry is 0.7 mL / min.

[0183] S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

[0184] The pore size of the filtration mesh is 18 μm, the thickness of the mesh is 4 mm, the vacuum degree is 180 Pa, the filtration time is 28 min, and the injection speed of the slurry is 0.7 mL / min.

[0185] (6) Performance testing

[0186] The examples of the present invention were tested in accordance with the GB / T10699-98 standard for calcium silicate insulation products, with reference to the technical requirements of JISA9510-84. Specimens measuring 40 mm x 40 mm x 160 mm were used to test density, compressive strength, and flexural strength, as well as heat resistance and linear shrinkage. Thermal conductivity was measured using a rapid determination method using specimens measuring 40 mm x 120 mm x 160 mm. Furthermore, hydrophobicity testing followed the GB10299-88 standard for hydrophobicity of thermal insulation materials.

[0187] Table 1: Density test results

[0188] Material <![CDATA[Density (kg / (m 3 ))]]> Example 1 155 Example 2 168 Example 3 172 Example 4 189 Example 5 213

[0189] Table 2: Compressive strength and flexural strength test results

[0190]

[0191] The thermal conductivity of the samples of the present invention was measured at an average test temperature of 21° C. The results are shown in Table 3. As can be seen from Table 3, the thermal conductivity of the test pieces in the embodiments of the present invention is 21.0 to 23.1 mW / (m·K).

[0192] Table 3: Thermal conductivity test results

[0193]

[0194]

[0195] The present invention successfully developed a fully hydrophobic product by incorporating a specialized composite waterproofing agent. According to the test method in accordance with GB10299-88, the surface hydrophobicity of the product reached over 98%. In a polyurethane foam water absorption test conducted according to relevant methods, the water absorption rate remained at 5% to 6% after 96 hours of immersion, reaching a leading level in China.

[0196] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

Claims

1. A method for preparing a high-strength thermal insulating calcium silicate material, characterized in that: include: S100, using deionized water, ceramic fiber and silica powder to prepare a pre-slurry; S200, adding silica aerogel and a foaming agent to the pre-slurry for dispersion treatment to prepare silica aerogel slurry; S300, using a calcium raw material and the silica aerogel slurry, adding reinforcing fiber, zeolite powder and a waterproofing agent to carry out a hydrothermal reaction to prepare microporous calcium silicate particles; S400, preparing a calcium silicate aluminum silicate slurry by combining the microporous calcium silicate particles and aluminum silicate fibers; S500, vacuum filtering the calcium silicate and aluminum silicate slurry to obtain a high-strength thermal insulation calcium silicate material; In S200, silica aerogel and a foaming agent are added to the pre-slurry for dispersion treatment to prepare the silica aerogel slurry, which includes the following steps: S201, taking the raw materials according to the mass ratio of pre-slurry: silica aerogel: foaming agent: deionized water = (55-65): (25-35): (10-20): (0-30), and adding the pre-slurry and the foaming agent to a stirring barrel; S202, while adding the silica aerogel, stirring the stirring barrel with a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a uniform silica aerogel slurry after 20 minutes; S203, if the slurry solidifies during stirring, adding deionized water; In S300, a calcium raw material and the silica aerogel slurry are added with reinforcing fiber, zeolite powder and a waterproofing agent for hydrothermal reaction to prepare microporous calcium silicate particles, including the following steps: S301, the calcium raw material is quicklime, the quicklime is dissolved into lime slurry, and the slurry is passed through a 200-mesh sieve; S302, the raw materials are taken in a mass ratio of quicklime: silica aerogel slurry: reinforcing fiber: zeolite powder: waterproofing agent = (53-68): (23-27): (2-6): (0.8-5): (0.5-3); S303, the raw materials are mixed, stirred under conditions of a temperature range of 205-225° C. and a pressure range of 1.7-2.4 MPa, and a hydrothermal reaction is carried out for more than 5 hours to obtain microporous calcium silicate particles.

2. The method for preparing the high-strength thermal insulating calcium silicate material according to claim 1, wherein: In S100, the steps of preparing a pre-slurry using deionized water, ceramic fiber, and silica powder include: S101, take the raw materials according to the mass ratio of deionized water: ceramic fiber: silica powder = (65-75): (20-30): (15-25); S102, adding deionized water and ceramic fibers into a stirring barrel, stirring the stirring barrel using a high-speed disperser at a speed of 600 rpm, and obtaining a uniform solution after 5 minutes; S103, adding silica powder into a stirring barrel, stirring the stirring barrel using a high-speed disperser, maintaining the speed at 1000 r / min, and obtaining a pre-slurry after 30 minutes.

3. The method for preparing the high-strength thermal insulating calcium silicate material according to claim 1, wherein: In S400, the step of preparing the microporous calcium silicate particles and aluminum silicate fibers to obtain a calcium silicate aluminum silicate slurry includes: S401, taking the raw materials in the mass ratio of microporous calcium silicate particles: aluminum silicate fibers: silicon dioxide adhesive: deionized water = (35-55): (35-55): (1-3): (10-20); S402, using a high-speed roller press to mix the raw materials at a speed of 4000-8000 r / min for 15-30 min to obtain calcium silicate aluminum silicate slurry.

4. The method for preparing the high-strength thermal insulating calcium silicate material according to claim 3, wherein: In S401, the length of the aluminum silicate fibers is 6 to 25 mm, and the aluminum silicate fibers are chopped into short pieces using a multi-axis vibration machine.

5. The method for preparing the high-strength thermal insulating calcium silicate material according to claim 1, wherein: In S500, the step of vacuum filtering the calcium silicate aluminum silicate slurry to obtain a high-strength thermal insulation calcium silicate material includes: S501, vacuum filtering the calcium silicate and aluminum silicate slurry in a vacuum filtration chamber, forming an aluminum silicate ceramic fiber layer on a filtration mesh plate in the vacuum filtration chamber, and taking the aluminum silicate ceramic fiber layer for later use; S502, re-prepare the vacuum filtration chamber, take calcium silicate aluminum silicate slurry, place an aluminum silicate ceramic fiber layer on the filtration mesh plate in the vacuum filtration chamber, vacuum filter the calcium silicate aluminum silicate slurry in the vacuum filtration chamber, and form a high-strength insulating calcium silicate material on the filtration mesh plate in the vacuum filtration chamber.

6. The method for preparing the high-strength thermal insulating calcium silicate material according to claim 5, characterized in that: In S501, the pore size of the filtration mesh is 5-20 μm, the mesh thickness is 1-5 mm, the vacuum degree is 120-200 Pa, the filtration time is 12-20 min, and the injection speed of the slurry is 0.3-0.8 mL / min.

7. The method for preparing the high-strength thermal insulating calcium silicate material according to claim 5, characterized in that: In S502, the pore size of the filtration mesh is 5-20 μm, the mesh thickness is 1-5 mm, the vacuum degree is 120-200 Pa, the filtration time is 25-32 min, and the injection speed of the slurry is 0.3-0.8 mL / min.

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