Preparation system and application of expanded perlite with shell / core composite structure

Abstract

The invention provides a shell / core composite structure expanded perlite preparation system and application, the system comprises a perlite particle preparation unit, a cladding powder preparation unit, a perlite particle cladding unit, a drying-preheating unit and a high-temperature expansion unit, the perlite particle preparation unit is connected with the cladding powder preparation unit and the perlite particle cladding unit, and the cladding powder preparation unit is connected with the perlite particle cladding unit; the perlite particle cladding unit is connected with the drying-preheating unit; and the drying-preheating unit is connected with the high-temperature expansion unit. The system can be applied to preparation of expanded perlite. The system disclosed by the invention has the beneficial effects that materials among the units in the system are smoothly conveyed and connected and are high in controllability, dust diffusion can be avoided, the dust can be effectively recycled, three wastes such as solid, liquid and gas are not generated, and the production efficiency is high; the system can be used for preparing closed-cell expanded perlite.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mineral product processing and its new material, in particular, relates to a shell / core composite structure expanded perlite preparation system and application. BACKGROUND

[0002] Perlite ore, including perlite type, obsidian type, pitchstone type, etc., is derived from the rapid cooling of acidic volcanic lava to form acidic silicate glass body, and the water in the lava is uniformly sealed in the glass body due to the fast cooling speed. Under appropriate high temperature conditions (generally 1000-1300℃), perlite ore particles can rapidly expand several times to form expanded perlite with light weight, porosity, and properties of heat insulation, sound insulation, fire resistance, etc. It is because the acidic silicate glass body melts and the water in it forms gas and expands in the molten glass body. Expanded perlite shows great application potential in many fields, especially as a production raw material for light and thermal insulation materials, which plays an important role in the construction and manufacturing industries.

[0003] However, the expanded perlite produced by the preparation system composed of the traditional preparation method has the defects of open cavities left by the gas escaping during the expansion of perlite ore, irregular shape, low strength, easy moisture absorption, etc. These problems lead to a decline in product performance during the preparation and use of composite materials. For example, open cavities can easily lead to the pouring of cementing / cementing material slurry, reducing the lightness and thermal insulation performance, and further limiting its application range. In order to overcome these defects, researchers have tried various improvement methods, including organic modification and surface coating technology, but these methods often bring new problems, such as affecting the bonding strength of the substrate, etc.

[0004] In recent years, with the advancement of technology, breakthroughs have been made in the production of closed-cell expanded perlite by using electric expansion furnace heating under precise temperature control conditions, aiming at the porous structure of expanded perlite. This method controls the temperature accurately to make the glass on the surface of the expanded perlite particles melt, making the surface of the expanded perlite particles collapse into closed-cell expanded perlite and seal the open pores, significantly improving the strength and water resistance of the material, while maintaining good thermal and sound insulation effects. However, this method is limited by the precise control of the furnace temperature, and the surface melting and collapse of the expanded perlite particles affect the bulk density, thermal conductivity and performance of the final product.

[0005] Therefore, it is of great significance to explore new methods for preparing closed-cell expanded perlite, to explore how to avoid dust dispersion, effective recycling, and to overcome the defects of the expanded perlite produced by the traditional system, such as the open pores on the surface of the expanded perlite, which can easily lead to the pouring of cementing / cementing material slurry and reduce the lightness and thermal insulation performance of the expanded perlite, etc.

[0006] Therefore, the shell / core composite structure expanded perlite preparation system has important significance for preparing a new type of closed expanded perlite material. The shell / core composite structure expanded perlite prepared by the new type of preparation system belongs to closed expanded perlite. The system can significantly improve the comprehensive performance of expanded perlite as a light, heat-insulating, fireproof and sound-absorbing material, thereby widening the application field and meeting the application requirements of higher standard buildings and extensive development. SUMMARY

[0007] In view of the deficiencies in the prior art, the present application aims to solve one or more problems in the prior art. For example, one of the purposes of the present application is to provide a shell / core composite structure expanded perlite preparation system which can realize smooth and controllable material transmission and connection between units, prevent dust diffusion and enable effective recycling, and does not generate solid-liquid-gas three wastes.

[0008] To achieve the above-mentioned purposes, the present application provides a shell / core composite structure expanded perlite preparation system, which can include a perlite particle preparation unit, a coating powder preparation unit, a perlite particle coating unit, a drying-preheating unit and a high-temperature expansion unit. The perlite particle preparation unit is connected with the coating powder preparation unit and the perlite particle coating unit. The coating powder preparation unit is connected with the perlite particle coating unit. The perlite particle coating unit is connected with the drying-preheating unit. The drying-preheating unit is connected with the high-temperature expansion unit.

[0009] According to one or more exemplary embodiments of the present application, the perlite particle preparation unit can include, in sequence in the feeding direction, a perlite ore raw material storage bin, a crushing module, a screening section device and a first perlite particle storage bin. The +10 mesh undersize of the discharge port of the screening section device enters the crushing module for further crushing, the -100 mesh undersize enters the coating powder preparation unit, and the +100 mesh to -10 mesh first perlite particles obtained after the screening section device is processed enter the first perlite particle storage bin.

[0010] According to one or more exemplary embodiments of the present application, the perlite ore raw material storage bin stores perlite ore raw material, and the perlite ore raw material can include one or more of perlite type, obsidian type, pine tar rock type and pumice-like perlite.

[0011] According to one or more exemplary embodiments of the present application, the perlite particle preparation unit can further include a dust removal facility. Dust suction ports are arranged at dust generating parts of the crushing module and the screening section device, and the dust suction ports are connected with the dust removal facility through pipelines.

[0012] According to one or more exemplary embodiments of one aspect of the present application, the shell powder preparation unit can include, in sequence in a feeding direction, a shell powder raw material storage bin, a crushing section device, a metering section device, and a grinding section device; the shell powder raw material storage bin is provided with a plurality of storage bins for storing glass shell powder raw material, porcelain shell powder raw material, and ceramic porcelain shell powder raw material, respectively; the grinding section device is configured to have a particle size of -200 mesh to -600 mesh, and the grinding section device is connected with a plurality of shell powder storage bins for storing different shell powder raw materials.

[0013] According to one or more exemplary embodiments of one aspect of the present application, the glass shell powder raw material can include perlite material, sodium feldspar, borax, and boric acid; the porcelain shell powder raw material can include perlite material, sodium / potassium feldspar, kaolin, and quartz sand; the perlite material can include dust collected from the perlite particle preparation unit, -100 mesh perlite powder, and / or perlite ore powder material collected from the shell powder preparation unit; the ceramic porcelain shell powder raw material can include refractory clay, shale, potassium feldspar, and quartzite.

[0014] According to one or more exemplary embodiments of one aspect of the present application, the perlite particle shell unit can include, in sequence, a binder dissolving section device, a material metering device, and a shell section device; the binder dissolving section device includes a plurality of dissolving tanks and a binder sol storage tank, the dissolving tanks are configured to dissolve inorganic binder and / or organic binder in industrial water to form binder sol, and the binder sol is stored in the binder sol storage tank; the material metering device includes a pump pressure pipe connected to the binder sol storage tank and a liquid meter installed thereon, a belt conveyor connected to the tail end of the perlite particle preparation unit and a belt scale installed thereon, and a powder conveying pipeline connected to the tail end of the shell powder preparation unit and a powder meter installed thereon; the material metering device is configured to make the perlite particles obtained from the perlite particle preparation unit, the binder sol of the binder sol storage tank, and the shell powder obtained from the perlite particle preparation unit enter the shell section in a predetermined metering ratio; the shell section device includes a stirring type particle coating machine, a rotary drum type particle coating machine, or a roller type particle coating machine, and the shell section device is configured to perform granulation to obtain second perlite particles having at least one or two coating layers of glass, porcelain, and ceramic on the surface.

[0015] According to one or more exemplary embodiments of one aspect of the present application, the drying-preheating unit can include one of an electric heating rotary kiln, a gas-fired rotary kiln and an oil-fired rotary kiln; the electric heating rotary kiln includes a pre-drying kiln body and a drying-preheating processing kiln body, wherein the temperature range of the pre-drying kiln body from the inlet to the outlet is 20-90℃, and the temperature gradient is 6-15℃ / m; the drying-preheating kiln body includes a drying section kiln body and a preheating section kiln body, wherein the temperature range of the drying section kiln body from the inlet to the preheating section kiln body is 100-300℃, and the temperature gradient is 30-40℃ / m; the temperature range of the preheating section kiln body from the drying section kiln body to the outlet is 500-850℃, and the temperature gradient is 30-40℃ / m; the gas-fired rotary kiln and the oil-fired rotary kiln each include a pre-drying kiln body, a drying kiln body and a preheating kiln body, wherein the temperature range of the pre-drying kiln body from the inlet to the outlet is 20-90℃, and the temperature gradient is 6-15℃ / m; the temperature range of the drying kiln body from the inlet to the outlet is 100-400℃, and the temperature gradient is 30-40℃ / m; the temperature range of the preheating kiln body from the inlet to the outlet is 500-850℃, and the temperature gradient is 30-40℃ / m; the drying-preheating unit processes and controls the moisture content of the obtained third perlite particles to be 2-3%, and the temperature to be 500-850℃.

[0016] According to one or more exemplary embodiments of one aspect of the present application, the high-temperature expansion unit can include one of an electric heating perlite expansion kiln, a gas-fired heating perlite expansion kiln and an oil-fired heating perlite expansion kiln; the electric heating perlite expansion kiln, the gas-fired heating perlite expansion kiln and the oil-fired heating perlite expansion kiln each include a feeding mechanism, an expansion furnace, a separator and a preheating collection module connected in sequence; the feeding mechanism causes the material obtained from the drying-preheating unit to be evenly and hotly sprinkled into the high-temperature expansion zone of the expansion furnace; the temperature of the high-temperature expansion zone is kept at 1100-1250℃; the material discharged from the expansion furnace enters the separator by wind, the material is separated from the hot air, and after separation, enters the preheating collection module, and after heat exchange and cooling, the shell / core composite structure expanded perlite is obtained and enters the product storage library; the preheating collection module can recover the waste heat in the expanded perlite product and the hot air, and the waste heat can be transferred to the drying-preheating unit.

[0017] Another aspect of the present application provides a use of a shell / core composite structure expanded perlite preparation system in the preparation of expanded perlite.

[0018] Compared with the prior art, the present application has the following beneficial effects at least one of which is included:

[0019] (1) The preparation system of the present application has the advantages that the first perlite particles of different particle sizes can be prepared by crushing and screening the perlite ore; the glassy, porcelain and ceramic coating powders can be obtained by crushing and grinding the coating powder raw materials; the second perlite particles can be formed by coating the first perlite particles with the binder; the coating powders can be bonded and coated on the second perlite particles; the third perlite particles can be obtained by drying, drying and preheating the second perlite particles; and the shell / core composite structure expanded perlite can be obtained by high-temperature expansion of the third perlite particles.

[0020] (2) The preparation system of the present application not only can prepare closed-cell expanded perlite, but also the shell / core composite structure expanded perlite prepared has a higher strength glassy and porcelain and / or ceramic hard material shell, and has higher expansion ratio and mechanical strength, lower bulk density and thermal conductivity, smaller water absorption and better acid and alkali resistance, and further has better lightweight, thermal insulation, sound insulation and other process properties.

[0021] (3) In the preparation system of the present application, the coating unit of the perlite particles is also a coating and granulation process during the coating process of the first perlite particles, and the formed perlite has high sphericity, and the shell / core composite structure expanded perlite formed after high-temperature expansion has higher expansion ratio and better particle packing performance.

[0022] (4) The third perlite particles obtained by the drying and preheating unit have a glassy coating component coated on the perlite particles, and the melting temperature of the glassy coating component is lower than the expansion temperature of the first expanded perlite particles, so that the viscous glass melt formed by the melting of the glassy coating component is coated on the perlite particles, and the coating layer is thinned into a continuous coating layer with the rapid expansion of the perlite ore particles, and can also trap the gas released during the expansion of the first perlite particles, and the expansion ratio of the expanded perlite is significantly increased. The porcelain and / or ceramic coating component coated on the surface of the glassy coating powder material is sintered into a porcelain or ceramic shell under high temperature conditions, but does not melt, and the non-melting sintering layer can better prevent the adhesion between the expanded perlite particles. BRIEF DESCRIPTION OF DRAWINGS

[0023] The above and other objects and features of the present application will become more apparent from the following description made with reference to the accompanying drawings, in which:

[0024] Figure 1 The structure of the shell / core composite structure expanded perlite preparation system of the present application is shown in the figure;

[0025] Figure 2AA photograph of a common expanded perlite is shown;

[0026] Figure 2B An optical microscope image of a common expanded perlite is shown;

[0027] Figure 2C An electron microscope image of a common expanded perlite is shown;

[0028] Figure 3A A photograph of a vitreous shell / core composite expanded perlite is shown;

[0029] Figure 3B A first optical microscope image of a vitreous shell / core composite expanded perlite is shown;

[0030] Figure 3C A second optical microscope image of a vitreous shell / core composite expanded perlite is shown;

[0031] Figure 3D A third optical microscope image of a vitreous shell / core composite expanded perlite is shown;

[0032] Figure 3E An electron microscope image of a vitreous shell / core composite expanded perlite is shown;

[0033] Figure 4A A photograph of a porcelain shell / core composite expanded perlite is shown;

[0034] Figure 4B An optical microscope image of a porcelain shell / core composite expanded perlite is shown;

[0035] Figure 4C An electron microscope image of a porcelain shell / core composite expanded perlite is shown;

[0036] Figure 5A A photograph of a ceramic shell / core composite expanded perlite is shown;

[0037] Figure 5B An optical microscope image of a ceramic shell / core composite expanded perlite is shown;

[0038] Figure 5C An electron microscope image of a ceramic shell / core composite expanded perlite is shown;

[0039] Figure 6A An SEM image of a composite shell / core composite expanded perlite is shown;

[0040] Figure 6B Another SEM image of a composite shell / core composite expanded perlite is shown.

[0041] MAIN REFERENCE NUMBERS EXPLANATION:

[0042] 1 - perlite particle preparation unit, 101 - storage silo, 102 - feeder, 103 - crushing module, 104 - screening section equipment, 105 - first dust removal facility, 2 - coated powder preparation unit, 201 - crushing section equipment, 202 - metering section equipment, 203 - grinding section equipment, 204 - second dust removal facility, 205 - coated powder raw material storage silo, 3 - perlite particle coating unit, 301 - dissolving tank, 302 - binder sol storage tank, 303 - nozzle, 304 - coating section equipment, 4 - drying-preheating unit, 401 - drying section, 402 - preheating section, 5 - high-temperature expansion unit. DETAILED DESCRIPTION

[0043] Hereinafter, a shell / core composite structure expanded perlite preparation system and application will be described in detail in conjunction with the accompanying drawings and exemplary embodiments.

[0044] In the description of the present application, it is to be understood that the terms "first", "second", "third", etc. are merely intended for the convenience of description and for the purpose of distinguishing one feature from another, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second", "third", etc. can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" or "several" is two or more. In the description of the present application, it is to be noted that, unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. The granularity expression in the present application, such as +100 mesh to -10 mesh, means that the particles are above 100 mesh screen and below 10 mesh screen, the particles cannot pass through the 100 mesh screen but can pass through the 10 mesh screen; that is, the negative number indicates that the particle size is smaller than the mesh size; the positive number indicates that the particle size is larger than the mesh size.

[0045] The application is about a preparation system and application of a shell / core composite structure expanded perlite with a heterogeneous material coated on the surface of perlite particles. The application provides a preparation system of a shell / core composite structure expanded perlite, which realizes the coating of a layer of glassy and / or porcelain and / or ceramic shell powder on the surface of perlite ore particles in advance, so that the perlite ore particles not only form a glassy inner layer and / or a porcelain and / or ceramic outer shell on the surface of the expanded perlite during the expansion process, but also can trap the gas released by the perlite ore particles during the high-temperature expansion process, thereby achieving the purposes of reducing the bulk density and thermal conductivity of the expanded perlite, improving the sphericity and mechanical strength, and the like. The application of the system achieves the purpose of preparing a shell / core composite structure expanded perlite, and the glassy, porcelain or ceramic heterogeneous material coated on the surface of the expanded perlite body is sintered to form a porcelain or ceramic outer shell, which not only makes the prepared expanded perlite material have higher strength, but also can be combined with a cement binder to form a high-strength composite material, thereby achieving the purpose of improving the performance of the expanded perlite and its composite material. The preparation system of the application can be used to prepare a shell / core composite structure expanded perlite, which can specifically include: a glassy shell / core composite structure expanded perlite, a porcelain shell / core composite structure expanded perlite, a ceramic shell / core composite structure expanded perlite, and a composite shell / core composite structure expanded perlite.

[0046] Here, the shell / core composite structure expanded perlite can include an outer shell and an inner core. Among them, the outer shell includes a single-layer shell composed of a vitreous layer, i.e., the final glass shell composite structure expanded perlite (vitreous shell / core composite structure expanded perlite) can be formed; the outer shell includes a double-layer shell composed of a vitreous layer and a porcelain layer, i.e., the final porcelain shell composite structure expanded perlite (porcelain shell / core composite structure expanded perlite) can be formed; the outer shell includes a double-layer shell composed of a vitreous layer and a ceramic layer, i.e., the final ceramic shell composite structure expanded perlite (ceramic shell / core composite structure expanded perlite) can be formed; the outer shell includes a three-layer shell composed of a vitreous layer, a porcelain layer and a ceramic layer, i.e., the final composite structure expanded perlite (composite shell / core composite structure expanded perlite) can be formed. In the case where the number of layers of the outer shell is greater than 2, the innermost coating layer of the outer shell must be a vitreous layer; the inner core is the expanded product of the perlite ore particles. Here, the total thickness of the outer shell can be 0.15mm-1mm; the thickness of the vitreous layer, the porcelain layer and the ceramic layer is 0.05-0.5mm respectively. The diameter of the inner core is determined by the size of the perlite particles and the expansion ratio, and the diameter range is 2mm-28mm. The combination of the vitreous layer of the shell and the core and the porcelain layer and the ceramic layer of the shell is a gradient change combination relationship of component mutual penetration in the expansion-fusion-sintering-firing process. The shell / core composite structure expanded perlite prepared by the system has higher expansion ratio, higher mechanical strength, lower water absorption and pulp absorption, higher sound absorption rate and lower thermal conductivity than ordinary expanded perlite, and can be used to produce light materials, thermal insulation materials, sound-absorbing and sound-insulating materials, fireproof and flame-retardant materials, etc., and can be used instead of floating beads and light or expanded ceramic particles. The shell / core composite structure expanded perlite is a closed-cell expanded perlite, and its properties can include: high expansion ratio: 3.5-8.0; light weight: bulk density is 200-350kg / m 3 ; high mechanical strength: cylinder pressure strength is 0.8-2.3MPa; good thermal insulation performance: thermal conductivity is 0.040-0.075W / (m·K); water absorption is less than 0.5%-1.5%; strong acid and alkali resistance: acid etching amount is less than 5%, alkali etching amount is less than 1%.

[0047] The invention coats the surface of perlite ore particles with a heterogeneous material that can form a vitreous and / or porcelain and / or ceramic shell. When the coated perlite ore particles are expanded, the vitreous heterogeneous material melts first and traps the gas released during the expansion of the perlite ore particles. This not only forms a vitreous shell on the surface of the expanded perlite, but also improves the expansion ratio, sphericity and overall performance due to the trapped gas. The porcelain and / or ceramic heterogeneous material forms a porcelain or ceramic shell on the surface of the expanded perlite, which is beneficial for forming a high-strength bond with the cementitious material. The new preparation system produces expanded perlite with a shell / core composite structure that has a low bulk density, low thermal conductivity, high sphericity and high strength. In particular, during the molding process of lightweight thermal insulation materials, the closed-cell structure of the expanded perlite does not allow the cementitious material slurry to flow in, and the high sphericity allows for a tighter packing and reduces the amount of cementitious material used. At the same time, the porcelain or ceramic shell forms a tight bond with the cementitious material, resulting in a composite material product with higher mechanical strength and better lightweight thermal insulation performance.

[0048] The system designed in the invention has a unique structure that includes a shell powder preparation unit, a perlite particle coating unit, a drying-preheating unit and a high-temperature expansion unit, which are the core units of the design system. The material transmission between the units is smooth and controllable, the preparation system can prevent dust dispersion and make it recyclable, and no solid, liquid and gas waste is generated, resulting in high production efficiency.

[0049] Example 1

[0050] The present exemplary embodiment provides a shell / core composite structure expanded perlite preparation system.

[0051] Figure 1 The structure of the shell / core composite structure expanded perlite preparation system of the invention is shown. The shell / core composite structure expanded perlite preparation system of the present exemplary embodiment will be described below with reference to Figure 1 The structure of the shell / core composite structure expanded perlite preparation system of the invention is shown. The shell / core composite structure expanded perlite preparation system of the present exemplary embodiment will be described below with reference to

[0052] As shown in Figure 1 The shell / core composite structure expanded perlite preparation system mainly includes a perlite particle preparation unit 1, a shell powder preparation unit 2, a perlite particle coating unit 3, a drying-preheating unit 4 and a high-temperature expansion unit 5. The perlite particle preparation unit 1 is connected to the shell powder preparation unit 2 and the perlite particle coating unit 3, and the shell powder preparation unit 2 is connected to the perlite particle coating unit 3. The perlite particle coating unit 3 is connected to the drying-preheating unit 4, and the drying-preheating unit 4 is connected to the high-temperature expansion unit 5.

[0053] In the present exemplary embodiment, the perlite particle preparation unit can include, in sequence in the feeding direction, a storage bin 101 (perlite ore raw material storage bin), a crushing module 103, a screening section device 104, and a first perlite particle storage bin.

[0054] The crushing module can include two or more of a jaw crusher, a roller crusher, an impact crusher, and a cone crusher. Here, the crushing is multi-stage crushing, and the crushing ratio of each stage can be set to 3-5, with an inspection screen to avoid over-crushing of the perlite ore, and the coarse particles (+10 mesh) on the screen are further crushed.

[0055] The screening section device can include a flat reciprocating screen or a linear vibrating screen, and the screening is a method of classifying the crushed perlite ore (-10 mesh) into different particle size specifications. The discharge port of the screening section device is connected to the discharge port of the crushing module and the coated powder preparation unit; the +10 mesh material on the screen of the discharge port of the screening section device enters the crushing module for further crushing, while the -100 mesh material on the screen enters the coated powder preparation unit, and the +100 mesh to -10 mesh first perlite particles obtained after processing of the screening section device enter the first perlite particle storage bin. That is, the first perlite particles can be obtained by screening: the glassy perlite particles with edges and corners in the particle size range of +100 mesh to -10 mesh obtained after processing of the perlite ore, which will serve as the core of the shell / core composite structure expanded perlite.

[0056] Further, the screen mesh of the screen can be provided with 10 mesh, 20 mesh, 25 mesh, 50 mesh, 80 mesh, and 100 mesh, and different particle size specifications of the perlite particles can be obtained.

[0057] Regarding the perlite particle preparation unit, the perlite ore raw material storage bin stores the perlite ore raw material, and the perlite ore raw material can include one or more of perlite type, obsidian type, pitchstone type, and pumice-like perlite.

[0058] Further, a plurality of first perlite particle storage bins are provided, each receiving the +100 mesh to -10 mesh particles of different particle size specifications obtained after processing of the screening section device; the different particle size specifications include -10 mesh to +20 mesh, -20 mesh to +25 mesh, -25 mesh to +50 mesh, -50 mesh to +80 mesh, and -80 mesh to +100 mesh. The first perlite particles of different particle size specifications can be transported to the first perlite particle storage bins of different particle size specifications by a belt conveyor. The first perlite particle storage bin can be connected to the coated powder preparation unit by a belt conveyor with a weighing device.

[0059] The first perlite particles of different particle sizes are used to prepare expanded perlite corresponding to different particle sizes, and the particle size of the selected coating powder (-200 mesh to -600 mesh) can also be selected according to the particle size of the first perlite (+100 mesh to -10 mesh). The combination of particles and powders of different particle sizes can obtain closed-cell coated expanded perlite with better performance, and further has more excellent physical and chemical properties. Preferably, the particle size of the perlite is coarse, and the coating material can be fine or coarse; the particle size of the perlite is fine, and the coating material is as fine as possible.

[0060] The raw material of the storage bin 101 can be connected with the crusher of the crushing module 103 by the feeder 102, and the crushers are connected in sequence by the belt conveyor. The crusher is connected with the screening section equipment 104 by the belt conveyor.

[0061] In the present exemplary embodiment, the perlite particle preparation unit can also include a dust removal facility, i.e., a first dust removal facility 105. The dust removal facility includes a bag dust collector, and dust suction ports are arranged at the dust generating parts of the crushing module and the screening section equipment, and the dust suction ports are connected with the bag dust collector through pipelines. Here, the dust removal is to purify the air in the workshop and collect the dust generated in the crushing and screening process of the perlite ore. The -100 mesh perlite powder obtained in the screening process, together with the perlite dust collected by the bag dust collector, can be used as the raw material of the glassy coating powder.

[0062] In the present exemplary embodiment, the coating powder preparation unit can prepare glassy coating powder, porcelain coating powder and ceramic coating powder with different formulations and particle sizes of -200 mesh to -600 mesh.

[0063] The coating powder preparation unit can include, in sequence in the feeding direction, a coating powder raw material storage bin 205, a crushing section equipment 201, a metering section equipment 202 and a grinding section equipment 203.

[0064] Among them, the coating powder raw material storage bin is provided with several coating powder raw material storage bins respectively storing glassy coating powder raw material, porcelain coating powder raw material and ceramic coating powder raw material. The coating powder raw material storage bins storing the same type of coating powder raw material can also have several coating powder raw material storage bins storing different materials (different particle size specifications or types).

[0065] Before the coating powder raw material enters the coating powder raw material storage bin, it can be processed by an impact crusher or a cone crusher to make the particle size of the material less than 10-50 mm. After mixing and grinding, the powder meeting the storage conditions can be obtained and can be conveyed to the coating powder raw material storage bin by a belt conveyor; the coating powder raw material with a particle size of less than 2-10 mm can be directly placed into other coating powder raw material storage bins.

[0066] The crushing section equipment includes two or more of jaw crusher, roller crusher, impact crusher and cone crusher. The crushers are connected by belt conveyors. Crushing is to crush the raw materials for preparing the coating powder, so as to facilitate subsequent metering and grinding.

[0067] The metering section equipment includes several sets of belt scales, for example, 3-5 sets. Metering is to meter the crushed materials and the powder raw materials, to form the formula coating powder materials and deliver them to the grinding section. The metering section equipment can be connected to the feeders of the coating powder raw material storage bins respectively, and the materials required by the formula of the glassy coating powder raw materials, the porcelain coating powder raw materials and the ceramic porcelain coating powder raw materials are weighed by the belt scales and then delivered uniformly to the mill hoppers of the grinding section.

[0068] The grinding section equipment includes Raymond mill or / and ultrafine grinding mill, and the grinding section equipment makes the particle size of the powder to be-200 mesh to-600 mesh. The grinding section equipment is connected with several coating powder storage bins, which respectively store different coating powder raw materials, i.e. the glassy coating powder raw materials, the porcelain coating powder raw materials and the ceramic porcelain coating powder raw materials are stored separately and not mixed. Grinding is to grind the formula coating powder materials into coating powder, and the coating powder is delivered to the coating powder storage bins of different formulas by pipeline. The coating powder storage bins can be connected to the grinding section equipment by pipeline.

[0069] Regarding the coating powder raw materials in the coating powder preparation unit, the glassy coating powder raw materials can include perlite materials, albite, borax and boric acid, which are in a mass percentage of (50-70):(20-35):(2-10):(0-10). The porcelain coating powder raw materials can include perlite materials, albite / potash feldspar, kaolin and quartz sand, which are in a mass percentage of (10-30):(20-40):(20-30):(10-20). The perlite materials in the glassy coating powder raw materials and the porcelain coating powder raw materials can include: the dust collected from the perlite particle preparation unit or / and the-100 mesh perlite powder or / and the perlite ore powder material collected from the coating powder preparation unit. The ceramic porcelain coating powder raw materials can include refractory clay, shale, potash feldspar and quartzite, which are in a mass percentage of (30-60):(20-40):(10-25):(5-15).

[0070] The preparation of glassy coated powder can be as follows: -100 mesh perlite powder or dust collected in the perlite particle preparation unit or perlite ore powder prepared by crushing in the coated powder preparation unit, and sodium feldspar, borax and boric acid materials prepared by crushing in the coated powder preparation unit are weighed and proportioned by belt scale in a mass percentage of (50-70):(20-35):(2-10):(0-10), and then fed into the feed inlet of the grinding equipment in the grinding section, and then mixed and ground to obtain glassy coated powder. The preparation of porcelain-coated powder can be as follows: -100 mesh perlite powder or dust collected in the perlite particle preparation unit or perlite ore powder prepared by crushing in the coating powder preparation unit, and sodium / potassium feldspar, kaolin, and quartz sand prepared by crushing in the coating powder preparation unit are weighed and proportioned by belt weigher in a mass percentage of (10-30):(20-40):(20-30):(10-20), and then fed into the feed inlet of the grinding equipment in the grinding section, and then mixed and ground to obtain porcelain-coated powder. The preparation of ceramic-coated powder can be as follows: refractory clay, shale, potassium feldspar, and quartzite prepared by crushing in the coating powder preparation unit are weighed and proportioned by belt weigher in the mass percentage of (30-60):(20-40):(10-25):(5-15), and then fed into the feed inlet of the grinding equipment in the grinding section, and then mixed and ground to obtain ceramic-coated powder.

[0071] In this exemplary embodiment, the coating powder preparation unit may further include a dust removal facility, namely a second dust removal facility 204. The dust removal facility may employ a bag filter to collect dust from the workshop, including installing dust suction ports and pipes at dust-generating locations in the crushing, metering, and grinding sections to purify the workshop air. Here, dust removal is for purifying the workshop air and collecting dust generated during the raw material crushing and grinding process.

[0072] In this exemplary embodiment, the perlite particle coating unit may include a binder dissolving section device, a material metering device, and a coating section device 304 connected in sequence.

[0073] The adhesive dissolving section equipment may include several dissolving tanks 301 and adhesive sol storage tanks 302. The number of dissolving tanks and adhesive sol storage tanks is the same, and can be 3 to 5. The dissolving tanks and adhesive sol storage tanks can be connected via pump lines. The dissolving tanks dissolve inorganic and / or organic adhesives in industrial water to form adhesive sol (the dissolving tank performs the dissolving operation; dissolution involves adding industrial water to the inorganic and / or organic adhesives, and after dissolving in industrial water, a viscous hydrosol is prepared). The adhesive sol is stored in the adhesive sol storage tanks. The adhesive sol storage tanks can be connected to material metering equipment via pump lines. Here, the dissolving tanks may be equipped with heating and stirring devices.

[0074] As for the inorganic binder or / and the organic binder, the inorganic binder can include one or more of water glass, sodium silicate and potassium silicate having a modulus of 1.0-2.9, configured to have a density of 1.36-1.50 g / cm 3 The organic binder can include one or more of carboxymethyl cellulose, sodium carboxymethyl cellulose, acrylic emulsion, vinyl acetate emulsion, polyvinyl acetal glue, emulsion glue, animal glue and vegetable glue, configured to include an aqueous sol having a solid content mass percentage of 0.5-2.0%. The inorganic binder and the organic binder can be used in combination, and when used in combination, the volume ratio of the inorganic binder to the organic binder is 5:1-2:1.

[0075] The material metering device includes a pump pressure pipe (binder sol pump pressure pipe) connected to the binder sol storage tank and a liquid meter installed thereon, a belt conveyor connected to the tail end of the perlite particle preparation unit (first perlite particle storage bin) and a belt scale installed thereon, and a powder conveying pipe connected to the tail end of the shell powder preparation unit (shell powder storage bin) and a powder meter installed thereon. Here, the discharge outlets of the binder sol pump pressure pipe, the belt conveyor and the powder conveying pipe are connected to the shell section device.

[0076] The material metering device allows the perlite particles obtained from the perlite particle preparation unit, the binder sol of the binder sol storage tank, and the shell powder obtained from the perlite particle preparation unit to enter the shell section in a predetermined metering ratio. Here, the predetermined metering ratio includes a mass ratio of the perlite particles to the binder sol of 100:(3-9). The shell powder includes vitreous shell powder, porcelain shell powder and ceramic shell powder, and the mass ratio of the perlite particles, the vitreous shell powder, the porcelain shell powder and the ceramic shell powder is (90-75):(10-20):(1-15):(1-15).

[0077] The shell section device includes a stirring type particle coating machine, a drum type particle coating machine or a roller type particle coating machine. A nozzle 303 is provided beside the shell section device, which can include a binder sol nozzle and an industrial water nozzle, and receives the binder sol and the industrial water required for the granulation process. The binder sol nozzle and the industrial water nozzle are respectively connected to the outlet of the binder sol pump pressure pipe and the outlet of the industrial water pipe. The discharge outlet of the shell section device is connected to the dry-preheating unit with a belt conveyor. The shell section device performs granulation to obtain second perlite particles having at least one or two coating layers of vitreous, porcelain and ceramic components on the surface. Specifically, the shell is first uniformly coated with a layer of binder sol on the surface of the first perlite particles, and then the measured shell powder is bonded to the surface of the first perlite particles, thereby forming the granulation process of one or two coating layers of vitreous, porcelain and ceramic components.

[0078] Regarding the coating / granulation process, first, a layer of binder sol is uniformly coated on the surface of the first perlite particles, the metered first perlite particles are first loaded into the running coating device, then the metered binder sol is sprayed through the nozzle, and the binder sol is uniformly coated on the surface of the first perlite particles through stirring, rotation or rolling of the coating section device; the metering of the perlite particles and the binder sol can be metered according to the mass ratio of the perlite particles of different particle size specifications to the binder of 100:(3-9). Here, uniform coating is to uniformly coat the binder on the surface of the first perlite particles. Then the metered coating powder is adhered to the surface of the first perlite particles coated with the binder; one or more (at least glassy) of the glassy, ceramic and ceramic component coating powder is added to the perlite particles uniformly coated with the binder sol in the running coating section device, and then the second perlite particles of one or more of the glassy, ceramic and ceramic component coating layers are formed. Specifically, it includes the following steps:

[0079] 1) uniformly add the metered glassy coating powder to the running coating device, so that the glassy coating powder is uniformly coated on the first perlite particles. The glassy coating component powder is uniformly coated on the first perlite particles, which means that the glassy coating powder does not exist independently when the coating is completed, and forms a glassy coating layer of perlite particles with dense texture and tends to be spherical.

[0080] 2) uniformly add the metered ceramic coating powder and / or ceramic powder to the running coating device of step 1), so that the ceramic coating powder and / or ceramic coating powder is uniformly coated on the glassy coating layer perlite particles of step 1); the ceramic and / or ceramic coating component powder is uniformly coated, which means that the ceramic and / or ceramic coating powder does not exist independently when the coating is completed, and forms a ceramic and / or ceramic coating layer of perlite particles with dense texture and tends to be spherical.

[0081] In step 2), when the ceramic and ceramic coating component powder exists independently, an atomizer can be used to spray water mist on the perlite particles, and until the coating component powder is completely coated on the perlite particles and there is no mutual adhesion of the particles.

[0082] In the present exemplary embodiment, the drying-preheating unit can include one of an electric heating rotary kiln, a fuel-fired rotary kiln and an oil-fired rotary kiln. Each rotary kiln includes a drying section 401 and a preheating section 402. The inlet of the rotary kiln is connected with the belt conveyor arranged at the outlet of the coating device of the perlite particle coating unit. The outlet of the rotary kiln is connected with the high-temperature expansion unit through an outlet pipeline. The material discharged from the outlet of the rotary kiln is the third perlite particles after drying and preheating treatment.

[0083] When the drying-preheating unit adopts the electric heating rotary kiln, the electric heating rotary kiln comprises a pre-drying kiln body and a drying-preheating treatment kiln body. The temperature range of the pre-drying kiln body from the inlet to the outlet is 20-90℃, the length of the kiln body is 5-10m, the temperature gradient is 6-15℃ / m, and the pre-drying time of the material is 2-30min. The inlet of the pre-drying kiln body is also connected with the sheathing section belt conveyor of the perlite particle sheathing unit through the exhaust port, and the outlet is the air inlet and is directly communicated with the drying-preheating treatment kiln body through the screw conveyor. The length of the drying-preheating kiln body is 16-20m, and the drying-preheating kiln body comprises a drying section kiln body (equivalent to the drying section 401) and a preheating section kiln body (equivalent to the preheating section 402). The length of the drying section kiln body is 8-10m, the temperature range from the inlet to the preheating section kiln body is 100-300℃, the temperature gradient is 30-40℃ / m, and the pre-drying time of the material is 1-10min. The inlet of the drying kiln body is also provided with the exhaust port of the drying-preheating treatment kiln body. The length of the preheating section kiln body is 8-10m, the temperature range from the drying section kiln body to the outlet is 500-850℃, the temperature gradient is 30-40℃ / m, and the pre-drying time of the material is 1-5min. The outlet of the preheating kiln body is the air inlet and is connected with the material inlet of the high-temperature expansion unit through the screw conveyor. The air entering the inlets of the pre-drying kiln body and the drying-preheating kiln body can be air or hot air generated by the high-temperature expansion unit. The exhaust port can be provided with an induced draft fan to exhaust the air containing water vapor. The flow of the air is from the high-temperature end of the rotary kiln body to the low-temperature end.

[0084] When the dry-preheating unit adopts a gas-fired rotary kiln or an oil-fired rotary kiln, the gas-fired rotary kiln and the oil-fired rotary kiln each include a pre-drying kiln body, a drying kiln body (equivalent to the drying section 401) and a preheating kiln body (equivalent to the preheating section 402). The temperature range of the pre-drying kiln body from the inlet to the outlet is 20-90°C, the kiln body length is 5-10 m, the temperature gradient is 6-15°C / m, and the pre-drying time of the material is 3-30 min. The inlet of the pre-drying kiln body is also connected with the exhaust outlet and the coating section belt conveyor of the perlite particle coating unit, and the outlet is the air inlet and is directly communicated with the drying kiln body through a screw conveyor. The length of the drying kiln body is 8-10 m, the temperature range from the inlet to the outlet is 100-400°C, the temperature gradient is 30-40°C / m, and the pre-drying time of the material is 1-15 min. The inlet of the drying kiln body is also provided with the exhaust outlet of the drying kiln body, and the outlet is the air inlet and is directly communicated with the preheating kiln body through a screw conveyor. The length of the preheating kiln body is 8-10 m, the temperature range from the inlet to the outlet is 500-850°C, the temperature gradient is 30-40°C / m, and the preheating time of the material is 1-5 min. The outlet of the preheating kiln body is the air inlet and is connected with the material inlet of the high-temperature expansion unit through a screw conveyor. The air inlet of the pre-drying kiln body, the drying kiln body and the preheating kiln body can be hot air generated by gas or oil combustion or by the high-temperature expansion unit. An induced draft fan can be arranged at the air outlet to exhaust the air containing water vapor, and the air flows from the high-temperature end to the low-temperature end of the rotary kiln body.

[0085] Finally, the dry-preheating unit can control the water content of the obtained perlite particles (third perlite particles) to be 2-3% and the temperature to be 500-850°C.

[0086] In the present exemplary embodiment, the dry-preheating unit can further include an electric control module and a temperature control module. The electric control module provides power for the electric heating rotary kiln, the gas-fired rotary kiln, the oil-fired rotary kiln and the induced draft fan, and the temperature control module can measure and control the kiln temperature of various rotary kilns.

[0087] The dry-preheating unit is a necessary link in the preparation system of the present application. The dry treatment is to reduce the water content on the surface of the second perlite particles, and the preheating treatment can reduce the water content inside the perlite particles. If the dry and preheating treatments are not performed, the water content on the surface and inside the perlite particles is too high, which can cause a large amount of heat to be absorbed due to the evaporation of the excessive water during the expansion of the perlite particles, reduce the temperature difference of the perlite particles during rapid heating, prolong the expansion time of the perlite particles, and affect the expansion multiple of the perlite particles. Meanwhile, the preheating can increase the temperature of the material before entering the expansion furnace, which is beneficial to the rapid reaching of the expansion temperature point of the perlite particles in the expansion furnace and the instant expansion of the perlite particles, and improves the expansion multiple.

[0088] In the present exemplary embodiment, the high-temperature expansion unit is capable of expanding the third perlite particles after drying and pre-heating treatment into at least one of glassy, porcelain, and ceramic coated shell / core composite structure expanded perlite (at least including glassy) of different particle size specifications. The high-temperature expansion unit can include one of an electrically heated perlite expansion kiln, a gas heated perlite expansion kiln, and an oil heated perlite expansion kiln.

[0089] The electrically heated perlite expansion kiln, the gas heated perlite expansion kiln, and the oil heated perlite expansion kiln each include a feeding mechanism, an expansion furnace, a separator, and a pre-heating collection module connected in sequence.

[0090] The feeding mechanism allows the material (third perlite particles) obtained from the drying-preheating unit to be evenly sprinkled into the high-temperature expansion zone of the expansion furnace while hot; the feeding mechanism can include a bucket elevator connected to the screw conveyor (outlet end) of the drying-preheating treatment unit, and a feeding port through which the third perlite particles lifted by the bucket elevator are connected to the expansion furnace. The temperature of the high-temperature expansion zone is maintained at 1100-1250°C, which can cause the perlite particles to rapidly heat up and rapidly expand, with the time for rapid heating and rapid expansion being 2-50s, of which the expansion time in the high-temperature expansion zone of the gas or oil heated perlite expansion furnace is 2-10s, and the expansion time in the high-temperature expansion zone of the electrically heated perlite expansion furnace is 5-50s.

[0091] The shell / core composite structure expanded perlite expanded by the expansion furnace enters the separator by means of air, and the perlite particle material is separated from the hot air. After separation, the shell / core composite structure expanded perlite particles enter the pre-heating collection module, and after heat exchange cooling, the shell / core composite structure expanded perlite can enter the product storage through the belt conveyor. Here, the separator is a cyclone classifier into which the shell / core composite structure expanded perlite expanded by the expansion furnace is sucked by an induced draft fan to separate the shell / core composite structure expanded perlite from the hot air.

[0092] The pre-heating collection module is capable of recovering the waste heat in the expanded perlite product and the hot air, and the waste heat can be transferred to the drying-preheating unit.

[0093] In the present exemplary embodiment, the high-temperature expansion unit can include a water cooling module, a dust collector, an electric control module, and a temperature control module. The water cooling module and the preheating collection module are auxiliary devices provided for protecting the equipment and recovering the residual heat in the expanded perlite product and the hot air of the shell / core composite structure; the recovered hot water and hot air can be used in the drying-preheating unit. The dust collector can include dust suction ports, pipes, and a bag-type dust collector, the dust suction ports are arranged at the dust generating parts of the components of the expansion kiln, and the dust suction ports are connected to the bag-type dust collector through the pipes, which can be used for dust removal of the air and hot air at the dust generating parts of the high-temperature expansion unit. The electric control and temperature control modules provide power for the equipment of the high-temperature expansion unit and can measure and control the temperature of the high-temperature expansion zone of the high-temperature expansion kiln. Here, the connection / setting position or arrangement of the water cooling module can be a conventional setting in the art.

[0094] In the high-temperature expansion process of the high-temperature expansion unit, the glassy coating powder material coated on the surface of the perlite ore particles is first melted, and the formed viscous glass melt is coated on the perlite particles. The viscous glass melt coating layer becomes a continuous coating layer with the rapid expansion of the perlite ore particles, and at the same time, it can trap the gas released during the first expansion of the perlite particles, and significantly increase the expansion multiple of the expanded perlite. The porcelain and / or ceramic coating components coated on the surface of the glassy coating powder material are fired into a porcelain shell or a ceramic shell under high-temperature conditions, but do not melt. The non-melting sintering layer can better prevent the adhesion between the expanded perlite particles. As a result, not only a composite structure expanded perlite with a glassy, porcelain or ceramic shell layer is formed, but also a closed-cell expanded perlite is formed.

[0095] Exemplary Embodiment 2

[0096] The present exemplary embodiment provides an application of a shell / core composite structure expanded perlite preparation system in the preparation of expanded perlite.

[0097] The shell / core composite structure expanded perlite can be prepared by the preparation system of exemplary embodiment 2, and specifically, the following can be prepared: glassy shell / core composite structure expanded perlite, porcelain shell / core composite structure expanded perlite, ceramic shell / core composite structure expanded perlite, and composite shell / core composite structure expanded perlite.

[0098] The shell / core composite structure expanded perlite prepared by the application has many advantages compared with ordinary expanded perlite.

[0099] According to Figure 2A , Figure 3A , Figure 4A , Figure 5AThe pictures show that the traditional device obtains traditional expanded perlite particles with low sphericity and open hole structure; and the glassy, porcelain and ceramic shell expanded perlite has high sphericity and closed hole structure. The material transmission between the units of the system is smooth and controllable, the dust diffusion can be prevented, the material can be effectively recycled, no solid-liquid-gas waste is generated, the temperature of the equipment can be accurately controlled, the production efficiency is high, and the product quality is good.

[0100] According to Figure 2B 、 Figure 2C The pictures show that the surface of the traditional expanded perlite has holes and voids formed when the gas escapes during the burning and expansion process, the surface is not smooth, and has sharp edges and corners. Therefore, the holes are easy to absorb the binder (such as cement paste, water glass, etc.).

[0101] According to Figure 3B to Figure 3E 、 Figure 4B 、 Figure 4C 、 Figure 5B 、 Figure 5C 、 Figure 6A 、 Figure 6B The above series of pictures show that the glassy inner layer, ceramic, porcelain or composite outer layer of the shell wraps the surface of the expanded perlite, and closes the holes of the expanded perlite. Therefore, it has excellent moisture-proof, waterproof performance and heat preservation, sound insulation and sound absorption performance. The outer surface layer of the porcelain has a cracked sintered layer formed during the high-temperature expansion process, which is beneficial to form a firm bond with the binder.

[0102] In order to better understand the above-mentioned exemplary embodiments of the present application, the following further illustrates them in conjunction with specific examples.

[0103] Example 1

[0104] (1) First, the perlite ore is crushed, screened and dedusted to obtain the first perlite particles. The jaw crusher and the roller crusher are selected for the crusher, and the 10-mesh plane reciprocating screen is selected for the screen to inspect and screen the raw materials, and the bag dust collector is used to collect the dust in the workshop. The jaw crusher and the roller crusher are selected to crush the shell powder, and then the Raymond mill is selected to grind the crushed shell powder.

[0105] (2) The glass shell shell powder formula is to store the perlite powder or dust collected in the perlite particle preparation unit with-100 mesh, and the shell powder preparation unit is crushed and prepared with sodium feldspar and borax materials with a mass percentage of 60:30:10, and then enters the inlet of the grinding equipment in the grinding section, and then is mixed and ground. The particle size of the glass shell shell powder is-400 to-500 mesh.

[0106] The vitreous shell coating powder formula is to store the perlite powder or dust of -100 mesh collected by the perlite particle preparation unit, and the sodium / potassium feldspar, kaolin, quartz sand crushed and prepared by the shell coating powder preparation unit in a mass percentage of 10:40:30:20, and then weighed by a belt scale, and then put into the inlet of the grinding equipment of the grinding section, and then mixed and ground. The particle size of the vitreous shell coating powder is -300 to -400 mesh.

[0107] The ceramic shell coating powder formula is to crush and prepare the refractory clay, shale, potassium feldspar, quartzite by the shell coating powder preparation unit in a mass percentage of 30:40:25:5, and then weighed by a belt scale, and then put into the inlet of the grinding equipment of the grinding section, and then mixed and ground. The particle size of the ceramic shell coating powder is -200 to -300 mesh.

[0108] (3) The first perlite particles of -10 to +20 mesh are selected, the binder is selected as a water glass glue solution with a modulus of 1.2 and a density of 1.42 g / cm 3 , and a Baume degree of 43.5; the first perlite particles and the binder are mixed in a mass ratio of 100:8, the binder is sprayed on the surface of the perlite particles by a sprayer, and then mixed uniformly.

[0109] (4) The first perlite particles, the glassy shell coating powder, the vitreous shell coating powder, and the ceramic shell coating powder are uniformly added into the stirring type particle coating machine in a mass ratio of 75:10:10:5 for shell coating, and finally the second perlite particles are obtained.

[0110] (5) The second perlite particles are put into the electric heating rotary kiln for drying and preheating. The length of the drying section is 10 m, the temperature rising rate is 30 ℃ / min, the drying temperature is 300 ℃, and the drying time is 2 min; the length of the preheating section is 8 m, the temperature is 850 ℃, the temperature rising rate is 40 ℃ / min, and the preheating time is 1 min. Finally, the third perlite particles with a water content of 2.3% are obtained.

[0111] (6) The third perlite particles are put into the electric heating perlite expansion kiln, and the temperature of the high-temperature expansion zone of the expansion furnace is kept at 1250 ℃, and the expansion time is 10 s. The obtained composite shell expanded perlite has a shell / core composite structure, including a shell and an inner core. The thicknesses of the glassy layer, the ceramic layer, and the ceramic layer are 0.41 mm, 0.19 mm, and 0.11 mm, respectively. The inner core is the expansion product of the first perlite, and the diameter of the inner core is determined by the particle size of the first perlite and the expansion multiple, and the diameter range is 24-28 mm.

[0112] The obtained composite shell expanded perlite has an expansion multiple of 7.6 and a bulk density of 230 kg / m 3; the compressive strength is 1.0 MPa; the thermal conductivity is 0.046 W / (m·K); the water absorption is less than 1.34%; the acid etching amount is 3.37%; and the alkali etching amount is 0.86%.

[0113] Example 2

[0114] (1) First, the obsidian type ore is crushed, screened and dedusted to obtain first perlite particles. The crusher is selected to be a counter-attack crusher and a cone crusher, and a 10-mesh plane reciprocating screen is selected as the screen mesh for screening the raw material. A bag dust collector is used to collect the dust in the workshop. The counter-attack crusher and the cone crusher are selected to crush the shell powder, and then the superfine grinding machine is selected to grind the crushed shell powder.

[0115] (2) The glass shell shell powder formula is to store the perlite powder or dust collected in the perlite particle preparation unit of-100 mesh, and the shell powder preparation unit is crushed and prepared. Feldspar, borax, boric acid materials are weighed and proportioned by belt scale according to mass percentage of 55:25:10:10, and then enter the inlet of the grinding equipment in the grinding section, and then mixed and ground. The particle size of the glass shell shell powder is-500~ -600 mesh.

[0116] The ceramic shell shell powder formula is to store the perlite powder or dust collected in the perlite particle preparation unit of-100 mesh, and the shell powder preparation unit is crushed and prepared. Feldspar, kaolin, quartz sand are weighed and proportioned by belt scale according to mass percentage of 25:30:30:15, and then enter the inlet of the grinding equipment in the grinding section, and then mixed and ground. The particle size of the ceramic shell shell powder is-400~ -500 mesh.

[0117] The ceramic shell shell powder formula is to store the perlite powder or dust collected in the perlite particle preparation unit of-100 mesh, and the shell powder preparation unit is crushed and prepared. Feldspar, kaolin, quartz sand are weighed and proportioned by belt scale according to mass percentage of 25:30:30:15, and then enter the inlet of the grinding equipment in the grinding section, and then mixed and ground. The particle size of the ceramic shell shell powder is-400~ -500 mesh.

[0118] (3) Select-25~ +50 mesh first perlite particles, and select carboxymethyl cellulose water-based glue with mass percentage of 2.0% as the binder. The mass ratio of the first perlite particles to the binder is 100:6, and the binder is sprayed on the surface of the perlite particles by a sprayer and mixed uniformly.

[0119] (4) The first perlite particles, the glass shell shell powder, the ceramic shell shell powder and the ceramic shell shell powder are uniformly added to the stirring type particle coating machine according to the mass ratio of 80:10:5:5 for shell coating, and the second perlite particles are finally obtained.

[0120] (5) The second perlite particles are added into a gas-fired rotary kiln for drying-preheating. The drying section is 8 m long, the temperature rising rate is 10℃ / min, the drying temperature is 400℃, and the drying time is 2 min; the preheating section is 9 m long, the temperature is 700℃, the temperature rising rate is 35℃ / min, and the preheating time is 3 min. Finally, the third perlite particles with a water content of 2.0% are obtained.

[0121] (6) The third perlite particles are added into a gas-fired perlite expansion kiln, and the temperature of the high-temperature expansion zone of the expansion furnace is kept at 1200℃, and the expansion time is 5 s. The obtained composite shell expanded perlite has a shell / core composite structure, including a shell and an inner core, wherein the thicknesses of the vitreous layer, the porcelain layer and the ceramic layer are 0.33 mm, 0.12 mm and 0.10 mm respectively; the inner core is the expansion product of the first perlite, and the diameter of the inner core is determined by the particle size of the first perlite and the expansion multiple, and the diameter ranges from 10 mm to 14 mm.

[0122] The obtained composite shell expanded perlite has an expansion multiple of 5.4, a bulk density of 280 kg / m 3 , a compressive strength of 1.4 MPa, a thermal conductivity of 0.058 W / (m·K), a water absorption of less than 1.27%, an acid etching amount of 2.88%, and an alkali etching amount of 0.75%.

[0123] Example 3

[0124] A composite shell expanded perlite and a preparation and application method thereof, comprising the following steps:

[0125] (1) First, the pine tar rock type ore is crushed, screened and dedusted to obtain first perlite particles. The crusher is selected to be a roller crusher and a impact crusher, and the screen is selected to be a 10-mesh plane reciprocating screen for screening the raw materials, and a bag dust collector is used to collect the dust in the workshop. The impact crusher and the cone crusher are selected to crush the coated powder, and then the ultra-fine grinding machine is selected to grind the crushed coated powder.

[0126] (2) The vitreous shell coated powder formula is that the -100-mesh perlite powder or dust collected in the perlite particle preparation unit and the feldspar, borax and boric acid materials crushed and prepared in the coated powder preparation unit are weighed and proportioned by a belt scale according to a mass percentage of 50:30:10:10, and then enter the inlet of the grinding equipment in the grinding section and are mixed and ground. The particle size of the vitreous shell coated powder is -500 to -600 mesh.

[0127] The vitreous shell coating powder formula is to weigh and proportion the -100 mesh perlite powder or dust stored in the perlite particle preparation unit and the sodium / potassium feldspar, kaolin, quartz sand crushed and prepared in the shell coating powder preparation unit by a belt scale according to a mass percentage of 30:40:20:10, and then enter the inlet of the grinding equipment in the grinding section, and then be mixed and ground. The particle size of the vitreous shell coating powder is -500 to -600 mesh.

[0128] The ceramic shell coating powder formula is to weigh and proportion the refractory clay, shale, potassium feldspar, quartzite crushed and prepared in the shell coating powder preparation unit by a belt scale according to a mass percentage of 60:20:10:10, and then enter the inlet of the grinding equipment in the grinding section, and then be mixed and ground. The particle size of the ceramic shell coating powder is -400 to -500 mesh.

[0129] (3) The first perlite particles with a particle size of -80 to +100 mesh are selected, the binder is a sodium silicate solution with a modulus of 1.0, a density of 1.38 g / cm 3 , a specific gravity of 40.4, and a mass percentage of 0.8% of polyvinyl formal glue sol, and the two binders are mixed uniformly according to a volume ratio of inorganic binder to organic binder of 3:1.

[0130] According to a mass ratio of the first perlite particles to the binder of 100:5, the binder is sprayed on the surface of the perlite particles by a sprayer and mixed uniformly.

[0131] (4) The first perlite particles, the glassy shell coating powder, the vitreous shell coating powder, and the ceramic shell coating powder are uniformly added into the stirring type particle coating machine according to a mass ratio of 87:10:1:2 for shell coating, and finally the second perlite particles are obtained.

[0132] (5) The second perlite particles are added into the fuel rotary kiln for drying and preheating. The length of the drying section is 10 m, the temperature rising rate is 30 ℃ / min, the drying temperature is 200 ℃, and the drying time is 10 min; the length of the preheating section is 10 m, the temperature is 500 ℃, the temperature rising rate is 30 ℃ / min, and the preheating time is 5 min. Finally, the third perlite particles with a water content of 2.9% are obtained.

[0133] (6) The third perlite particles are added into the fuel heating perlite expansion kiln, and the temperature of the high-temperature expansion zone of the expansion furnace is kept at 1120 ℃, and the expansion time is 10 s. The obtained composite shell expanded perlite has a shell / core composite structure, including a shell and an inner core. The thicknesses of the glassy layer, the vitreous layer, and the ceramic layer are 0.11 mm, 0.08 mm, and 0.06 mm, respectively. The inner core is the expansion product of the first perlite, and the diameter of the inner core is determined by the particle size of the first perlite and the expansion multiple, ranging from 2 to 4 mm.

[0134] The obtained composite shell expanded perlite has an expansion ratio of 3.8, a bulk density of 340 kg / m 3 ; a compressive strength of 2.1 MPa; a thermal conductivity of 0.069 W / (m·K); a water absorption of less than 1.08%; an acid etching amount of 3.6%; and an alkali etching amount of 0.65%.

[0135] In summary, the advantages of the present application include at least one of the following:

[0136] (1) The shell / core composite structure expanded perlite prepared by the preparation system has a glassy, porcelain and / or ceramic shell, which not only has a closed pore structure, high strength, but also high sphericity, and is easy to form a more compact packed body; these characteristics can greatly reduce the amount of organic binder or inorganic cementing material required in the preparation of expanded perlite composite materials; further, not only can the production cost be reduced, but also the thermal insulation performance, sound insulation and sound absorption performance of the expanded perlite composite material can be significantly improved after reducing the amount of organic binder or inorganic cementing material (such as cement); at the same time, it also has important significance for preparing high-strength expanded perlite composite materials.

[0137] (2) The preparation system of the present application not only has a dust removal system at the parts of the processing equipment where dust is easily produced in different preparation units, so as to achieve no dust pollution in the processing workshop; but also the collected dust can be used as the raw material of the coating powder, so that the preparation system of the present application does not produce waste gas, waste water and solid waste; especially important is that the shell / core composite structure expanded perlite prepared by the preparation system of the present application has a hard shell, and almost no dust is produced during the subsequent transportation, composite material and product preparation and use, which also achieves no pollution in the transportation, storage and subsequent production environment of the products.

[0138] (3) The organic combination of each preparation unit of the preparation system of the present application realizes the unique design and preparation of the glassy, porcelain or ceramic shell composite structure expanded perlite structure, effectively seals the internal pores after the first perlite is expanded, effectively reduces the adsorption of water and humidity by the expanded perlite, and further ensures the lightweight performance and excellent thermal insulation and sound insulation performance of the shell / core composite structure expanded perlite material during use; the composite material or product prepared by the shell / core composite structure expanded perlite is more outstanding in process technology performance, especially in the contemporary society pursuing high efficiency, energy saving and green environmental protection, and has a particularly broad application prospect.

[0139] (4) The expanded perlite of the glassy, vitreous or ceramic shell / core composite structure prepared by the preparation system of the present application has particularly excellent mechanical strength, high surface hardness and good bonding property with the organic binder or inorganic cementitious material matrix, and further has the excellent properties of light weight, thermal insulation, sound insulation and the like, and can be used to replace the ceramic granule, floating bead, glass microbead and the like.

[0140] Although the present application has been described above with reference to the exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes can be made thereto without departing from the spirit and scope of the application as defined in the appended claims.

Claims

1. A system for preparing shell / core composite expanded perlite, characterized in that, The system includes a perlite particle preparation unit, a coated powder preparation unit, a perlite particle coating unit, a drying-preheating unit, and a high-temperature expansion unit, wherein... The perlite particle preparation unit is connected to the coating powder preparation unit and the perlite particle coating unit; the coating powder preparation unit is connected to the perlite particle coating unit; the perlite particle coating unit is connected to the drying-preheating unit; and the drying-preheating unit is connected to the high-temperature expansion unit.

2. The shell / core composite expanded perlite preparation system according to claim 1, characterized in that, The perlite particle preparation unit includes: a perlite ore raw material storage bin, a crushing module, a screening section equipment, and a first perlite particle storage bin connected in sequence in the feeding direction; The material oversized by the 10-mesh screen at the discharge port of the screening section enters the crushing module for further crushing, and the material undersized by the 100-mesh screen enters the coating powder preparation unit. The +100-mesh to -10-mesh first perlite particles obtained after processing by the screening section enter the first perlite particle storage bin.

3. The shell / core composite expanded perlite preparation system according to claim 2, characterized in that, The perlite ore storage silo stores perlite ore, which includes one or more types of perlite, obsidian, resinstone, and pumice perlite.

4. The shell / core composite expanded perlite preparation system according to claim 2, characterized in that, The perlite particle preparation unit also includes a dust removal facility. Dust suction ports are provided at the dust-generating parts of the crushing module and screening section equipment, and the dust suction ports are connected to the dust removal facility through pipes.

5. The shell / core composite expanded perlite preparation system according to claim 1, characterized in that, The coating powder preparation unit includes: a coating powder raw material storage silo, a crushing section, a metering section, and a grinding section connected sequentially in the feeding direction; several coating powder raw material storage silos are provided, which respectively store glassy coating powder raw materials, ceramic coating powder raw materials, and ceramic coating powder raw materials; the grinding section equipment makes the particle size of the powder from -200 mesh to -600 mesh, and the grinding section equipment is connected to several coating powder storage silos, which respectively store different coating powder raw materials.

6. The shell / core composite expanded perlite preparation system according to claim 5, characterized in that, The vitreous coating powder raw material includes perlite, sodium feldspar, borax, and boric acid; the ceramic coating powder raw material includes perlite, sodium / potassium feldspar, kaolin, and quartz sand; the perlite includes dust collected from the perlite particle preparation unit and / or -100 mesh perlite powder and / or perlite ore powder collected from the coating powder preparation unit; the ceramic coating powder raw material includes refractory clay, shale, potassium feldspar, and quartzite.

7. The shell / core composite expanded perlite preparation system according to claim 1, characterized in that, The perlite particle coating unit includes a binder dissolving section, a material metering section, and a coating section connected in sequence. The adhesive dissolving section equipment includes several dissolving tanks and adhesive sol storage tanks. The dissolving tanks dissolve inorganic and / or organic adhesives in industrial water to form adhesive sols, and the adhesive sols are stored in the adhesive sol storage tanks. The material metering equipment includes a pump pressure pipe connected to the binder sol storage tank and a liquid metering device installed on it, a belt conveyor connected to the tail end of the perlite particle preparation unit and a belt scale installed on it, and a powder conveying pipeline connected to the tail end of the shelled powder preparation unit and a powder metering device installed on it. The material metering equipment ensures that the perlite particles obtained from the perlite particle preparation unit, the binder sol in the binder sol storage tank, and the coating powder obtained from the perlite particle preparation unit enter the coating section in a predetermined metering ratio. The coating section equipment includes a stirring-type pellet coating machine, a rotary drum pellet coating machine, or a roller pellet coating machine. The coating section equipment performs granulation to obtain second perlite particles with at least one or two coating layers of glass, porcelain, and ceramic.

8. The shell / core composite expanded perlite preparation system according to claim 1, characterized in that, The drying-preheating unit includes one of an electrically heated rotary kiln, a gas-fired rotary kiln, and an oil-fired rotary kiln. The electrically heated rotary kiln includes a pre-drying kiln body and a drying-preheating kiln body. The temperature range from the inlet to the outlet of the pre-drying kiln body is 20–90℃, with a temperature gradient of 6–15℃ / m. The drying-preheating kiln body includes a drying section and a preheating section. The temperature range from the inlet to the outlet of the drying section is 100–300℃, with a temperature gradient of 30–40℃ / m. The temperature range from the inlet to the outlet of the preheating section is 500–850℃, with a temperature gradient of 30–40℃ / m. Both the gas-fired rotary kiln and the oil-fired rotary kiln include a pre-drying kiln body, a drying kiln body, and a preheating kiln body. The temperature range from the inlet to the outlet of the pre-drying kiln body is 20–90℃, with a temperature gradient of 6–15℃ / m. The temperature range from the inlet to the outlet of the drying kiln body is 100–400℃, with a temperature gradient of 30–40℃ / m. The temperature range from the inlet to the outlet of the preheating kiln body is 500–850℃, with a temperature gradient of 30–40℃ / m. The moisture content of the third perlite particles obtained by the drying-preheating unit is 2-3%, and the temperature is 500-850℃.

9. The shell / core composite expanded perlite preparation system according to claim 1, characterized in that, The high-temperature expansion unit includes one of an electrically heated perlite expansion kiln, a gas-fired heated perlite expansion kiln, and an oil-fired heated perlite expansion kiln; the electrically heated perlite expansion kiln, the gas-fired heated perlite expansion kiln, and the oil-fired heated perlite expansion kiln all include a feeding mechanism, an expansion furnace, a separator, and a preheating collection module connected in sequence. The feeding mechanism ensures that the material obtained from the drying-preheating unit is evenly and hotly sprinkled into the high-temperature expansion zone of the expansion furnace. The temperature in the high-temperature expansion zone is maintained at 1100-1250℃; the material from the expansion furnace enters the separator by air, where the material is separated from the hot air. After separation, it enters the preheating and collection module, and after heat exchange and cooling, it becomes shell / core composite expanded perlite, which then enters the product storage warehouse. The preheating collection module can recover waste heat from the expanded perlite product and hot air, and the waste heat can be transferred to the drying-preheating unit.

10. The application of the shell / core composite expanded perlite preparation system according to claim 1 in the preparation of expanded perlite.

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