Preparation method and application of basalt colored sand

Abstract

The invention particularly relates to a preparation method and application of basalt colored sand, and belongs to the technical field of colored sand. According to the preparation method of the basalt colored sand, basalt is used as a colored sand base material, silicate is used as a main component of a coloring binder, fluorocarbon resin and acrylic resin are used as a color fixing liquid coating, and a metal oxide inorganic pigment is used as a coloring pigment of color paste. The method sequentially comprises the steps of coloring a binder, coating a color paste, sintering at medium temperature, coating a color fixing solution, calcining at low temperature and the like, so that uniform color fixing coating of the color paste is realized on the surface of the basalt base material; the prepared basalt color sand is uniform in color and luster and good in chemical stability, and can fully meet the use requirements of color stone metal tiles in extreme environments such as thickness resistance, chemical resistance and high temperature resistance; the preparation method effectively replaces a traditional high-temperature sintering preparation process of the colored sand, is simple, efficient, green and environmentally friendly, has high economical efficiency and operability and is suitable for batch production of the colored sand.

Description

TECHNICAL FIELD

[0001] The present application particularly relates to a preparation method and application of basalt colored sand, and belongs to the technical field of colored sand. BACKGROUND

[0002] Color stone metal tile, as a new type of high-end building roofing material, is widely used in high-end residential, villa, commercial building and public facilities due to its light weight, high strength, beautiful appearance, rich color, convenient construction, anti-seismic and windproof, and environmental protection and recycling. The core structure of the color stone metal tile is a high-strength aluminum-zinc alloy steel plate, and the surface is covered with a layer of colored sand particles which plays a role of weather resistance, corrosion resistance and appearance decoration. The layer of colored sand not only gives the metal tile a rich and colorful decorative effect, but also protects the internal metal substrate from environmental hazards such as ultraviolet rays, rainwater, temperature difference and corrosion.

[0003] Colored sand is mainly divided into two categories: natural colored sand and artificial colored sand. Among them, the source of natural colored sand is various, and there are problems such as unstable color batch, irregular particle shape, large difference in hardness and specific gravity of different components, poor stability in high temperature environment, easy to appear powdering or peeling phenomenon, and difficult to meet the durability requirements of color stone metal tile. Although artificial colored sand overcomes some shortcomings of high-temperature colored sand, its production process usually relies on high-temperature melting process; for example, Chinese patent CN202411967547.9 discloses a preparation method of high-temperature ceramic colored sand for color stone metal tile, which comprises the following steps: raw material selection, raw material mixing, grinding treatment, high-temperature melting, cooling and particle forming, screening treatment, surface coating and color regulation. The preparation method takes kaolin, feldspar, basalt sand and titanium dioxide as main raw materials, and prepares ceramic textured colored sand particles through high-temperature melting treatment at 1200°C~1400°C; Chinese patent CN201410412978.9 discloses a high-temperature sintered colored sand and a preparation method thereof. The colored sand comprises silicate mineral particles and a surface color powder layer, and the surface color powder layer is formed by high-temperature calcination of color paste wrapped on the surface of silicate mineral particles. According to the required color, the color paste is prepared by ball milling and uniformly mixing water glass, kaolin, industrial borax and inorganic colorant, and then the prepared color paste is mixed with silicate mineral particles according to the weight ratio in a rotary drum furnace, dried, and calcined at 600~1100°C to obtain high-temperature sintered colored sand. Although the above-mentioned colored sand preparation overcomes some problems existing in natural colored sand, the prepared colored sand is high-temperature durable, color stable and texture solid, but its preparation process needs to rely on kiln high-temperature calcination, which has problems such as high cost and high pollution, which becomes a key bottleneck restricting the large-scale production of ceramic colored sand.

[0004] In the selection of colored sand manufacturing base material, basalt is increasingly becoming a widely concerned material selection. Basalt is a natural rock formed by volcanic eruption, which is widely distributed, high hardness, wear resistance, low thermal expansion coefficient (about 5x10-6 / ℃], strong resistance to acid and alkali erosion, excellent impact resistance and ultraviolet aging resistance, excellent water resistance and frost resistance, rough surface, strong adhesion, and good compatibility with commonly used inorganic binders (such as sodium silicate) or organic binders (such as modified resin) in chemical properties, therefore, it is of great significance to develop a medium and low temperature colored sand preparation process based on basalt as the base material to promote the green production of colored sand. SUMMARY

[0005] In view of the problems of harsh preparation conditions and high production cost existing in the preparation of existing colored sand, the present application provides a preparation method and application of basalt colored sand, which uses basalt as the base material of colored sand, and effectively replaces the high-temperature sintering process of traditional colored sand through the way of medium and low temperature sintering in sections and the step-by-step coating of coloring binder, color paste and fixing liquid, which is simple, efficient, green and environmentally friendly, has high economic efficiency and operability, and is suitable for batch production of colored sand; the basalt colored sand prepared has uniform color and good chemical stability, and can fully meet the use requirements in extreme environments such as chemical resistance, high temperature resistance and the like of colored stone metal tile.

[0006] The technical scheme of the present application is as follows: The present application provides a preparation method of basalt colored sand, which uses basalt as the base material, coats coloring binder and color paste on the surface of the base material in sequence, then sintering the coated base material in a heating environment of 380~420℃, after cooling, uniformly coats fixing liquid on the surface, then sintering the obtained base material coated with fixing liquid in a heating environment of 160~200℃, and further obtaining the basalt colored sand.

[0007] The coloring binder is uniformly mixed by sodium silicate, wetting agent and dispersing agent; the fixing liquid is uniformly mixed by fluorocarbon resin, acrylic resin, deionized water, dispersing agent, silane coupling agent, leveling agent and defoaming agent; and the color paste is metal oxide inorganic pigment color paste.

[0008] Further, the 380~420℃ sintering and the 160~200℃ sintering are both carried out by electromagnetic heating roller.

[0009] Further, horizontal stirrers are used to coat the coloring binder, color paste and fixing liquid on the surface of the base material.

[0010] Further, the preparation method of basalt colored sand is carried out by continuous production process.

[0011] Further, the preparation method of basalt colored sand comprises the following specific steps: S1, basalt sand particles with mesh number between 16 and 40 are put into a horizontal mixer, 1.5-2% of coloring binder by mass of the basalt sand particles is added and fully stirred and mixed with the basalt sand particles, then 2.0-5.0% of color paste by mass of the basalt sand particles is added and fully stirred and mixed, so as to obtain sand particles coated with color paste on the surface; S2, the sand particles coated with color paste on the surface are transported into an electromagnetic heating roller for sintering, the electromagnetic heating roller temperature is set to 380-420℃, the rotation speed of the conveying screw and the roller is adjusted according to the length of the electromagnetic heating roller to control the residence time of the sand particles, when the discharge temperature of the sand particles is not less than 300℃, the discharge is performed; S3, the sand particles after step S2 are transported into a horizontal mixer, the surface of the sand particles is uniformly sprayed with color fixing liquid at a flow rate of 0.5-1.0 m / s, so as to obtain sand particles coated with color fixing liquid on the surface; S4, the sand particles coated with color fixing liquid on the surface are transported into an electromagnetic heating roller for sintering, the electromagnetic heating roller temperature is set to 160-200℃, the rotation speed of the conveying screw and the roller is adjusted according to the length of the electromagnetic heating roller to control the residence time of the sand particles, when the discharge temperature of the sand particles reaches 100-150℃, the discharge is performed, and after cooling and screening, the basalt colored sand is obtained.

[0012] Further, in step S2, the length of the electromagnetic heating roller is 8 m, the rotation speed of the conveying screw is set to 45 r / min, and the rotation speed of the roller is set to 40 r / min.

[0013] Further, in step S4, the length of the electromagnetic heating roller is 8 m, the rotation speed of the conveying screw is set to 45-60 r / min, and the rotation speed of the roller is set to 35-40 r / min.

[0014] Further, the mass fractions of the components in the coloring binder are as follows: 88-92 parts of sodium silicate, 6-8 parts of wetting agent, and 2-4 parts of dispersing agent; the coloring binder is prepared by putting the components into a high-speed disperser according to the mass fractions, stirring and mixing at 1500-1700 r / min for 30-40 min.

[0015] Preferably, in the coloring binder, the wetting agent is BYK-349 (main component: polyether modified polysiloxane) or TEGO Wet 260 (polysiloxane polyether copolymer), which can effectively reduce the surface tension of the silicate solution, so that it quickly spreads and penetrates into the micropores on the surface of the sand particles; the dispersing agent is BYK-191 (main component: polyacrylic acid sodium salt) or Dispex AA 4040 (polyacrylic acid ammonium salt), which is used to stabilize the silicate system and inorganic fillers, prevent agglomeration, and ensure uniform coating.

[0016] Further, the mass fractions of the components in the color fixing liquid are as follows: fluorocarbon resin 40-50 parts, acrylic resin 20-30 parts, deionized water 20-25 parts, dispersant 2-3 parts, silane coupling agent 1-2 parts, leveling agent 0.5-1 part, and defoaming agent 0.5-1 part; the color fixing liquid is prepared by adding the components into a high-speed disperser according to the mass fractions, stirring at 1500-1700 r / min for 30-40 min.

[0017] Preferably, in the color fixing liquid, the fluorocarbon resin is a fluorocarbon resin emulsion, the acrylic resin is an acrylic resin emulsion; the dispersant is BYK-2050 (main component: high molecular block copolymer containing anchoring groups) or EFKA-4585 (high molecular carboxylate), which has strong anchoring ability to inorganic pigments and can provide long-term dispersion stability; the silane coupling agent can be KH-550 (component: γ-aminopropyl triethoxysilane), the amino group of which can react with the resin, and the other end can be combined with the surface of the sand particles, greatly enhancing the adhesion of the resin film to the underlying silicate / sand particles; KH-560 (γ-glycidyl ether propyl trimethoxysilane) can also be selected, which provides excellent water resistance; the leveling agent can be BYK-333 (main component: polyether modified polydimethylsiloxane) or TEGO Glide 410 (polysiloxane-polyether copolymer), which can effectively reduce the surface tension, eliminate the Bernoulli vortex, make the resin liquid film flow evenly, and avoid orange peel; the defoaming agent is BYK-024 or TEGO Foamex 810, which can strongly defoam and has good compatibility, preventing the generation of bubbles during production and coating.

[0018] Further, the metal oxide inorganic pigment color paste comprises the following components in the mass fractions: metal oxide inorganic pigment 20-50 parts, sodium silicate 40-70 parts, dispersant 2-5 parts, anti-settling agent 2-5 parts, and defoaming agent 0.5-1 part. The metal oxide inorganic pigment is one or more of iron oxide red Fe2O3 (red), cobalt blue CoAl2O4 (blue), zinc-iron yellow ZnFe2O4 (yellow), carbon black C (black), and chromium green Cr2O3 (green). The metal oxide inorganic pigment color paste is prepared by adding the components into a high-speed disperser according to the mass fractions, stirring at 1500-1700 r / min for 30-40 min.

[0019] Preferably, in the metal oxide inorganic pigment paste, the dispersant is BYK-110 (main component: low molecular weight unsaturated carboxylic acid polymer) or EFKA-4010 (modified polyacrylate); the anti-settling agent is BYK-410 (main component: modified urea solution), which can form a thixotropic network in the paste to prevent the pigments from hardening and precipitating during storage, and is easy to redisperse; gas phase silicon dioxide (such as AEROSIL 200) can also be used, which forms a three-dimensional network through hydrogen bonds, and has a significant anti-settling effect; the defoaming agent is BYK-021 or TEGO Foamex 1488, which can quickly remove the micro-bubbles introduced by stirring.

[0020] The application further provides a basalt colored sand prepared by the preparation method of the basalt colored sand.

[0021] The colored sand prepared by the preparation method of the basalt colored sand has bright and uniform color, good wear resistance and weather resistance, and can be applied to the preparation of colored stone metal tiles.

[0022] Compared with the prior art, the application has the following beneficial effects: 1. The application provides a method for preparing colored sand under medium and low temperature conditions, which realizes progressive functional enhancement of "dust adsorption, pigment adhesion and dense protection" of the colored sand through the steps of coating with a coloring binder, a paste, medium temperature sintering, coating with a color fixing liquid and low temperature calcination, and the prepared colored sand fully meets the requirements of water resistance, acid resistance, alkali resistance, high temperature resistance and other extreme use environments; the main component of the coloring agent is sodium silicate, which can preliminarily bond and adsorb the dust adsorbed on the surface of the basalt, and effectively promote the uniform distribution of the subsequent coated paste; the medium temperature sintering at 380-420 DEG C can make the sodium silicate uniformly coated on the surface of the base material form a stable silicon-oxygen three-dimensional network structure, and then produce firm and stable chemical bonding between the paste particles and the base material, so that the paste is stably coated, and the mechanical strength and wear resistance of the system are significantly improved; the main components of the color fixing liquid are acrylic resin, fluorocarbon resin and other additives, the fluorocarbon resin has good weather resistance, chemical resistance, stain resistance and ultraviolet resistance, the acrylic resin can increase the wettability of the color fixing liquid, and after being solidified by low temperature sintering at 160-180 DEG C, the acrylic resin and the fluorocarbon resin can form a continuous and dense polymer film layer on the surface of the basalt base material coated with the paste, and the film layer has good flexibility and adhesion, and can effectively isolate external erosion media, so as to improve the weather resistance and acid and alkali resistance of the colored sand, and avoid oxidation, hydrolysis or discoloration of the inorganic pigment.

[0023] 2、Different from the previous basalt colored sand preparation process, the application effectively overcomes the high energy consumption defect caused by high temperature calcination in the traditional colored sand preparation process through the optimization of the production process, and realizes the breakthrough of the low energy consumption production mode of the colored sand; before coating the color paste, the application first coats the coloring binder mainly composed of sodium silicate, and the inorganic pigment of the metal oxide of the color paste is fixed on the surface of the base material through the chemical bonding effect of the three-dimensional network structure of silicon oxygen formed after the sintering of sodium silicate, so that the heat energy required by the process is reduced from more than 1200 DEG C in the traditional high-temperature colored sand preparation process to 380-420 DEG C, which is clean, environmentally friendly and low in energy consumption; meanwhile, after the medium-temperature sintering, the application coats the color fixing liquid and forms the color fixing layer through 160-200 DEG C low-temperature sintering, and further provides dense protection for the inner layer of the colored sand; through the cooperation of the three-step coating of the coloring binder, the color paste and the color fixing liquid and the medium-temperature and low-temperature segmented sintering and solidification, the process meets the performance index of the colored sand, reduces the sintering temperature from more than 1200 DEG C in the traditional process to 380-420 DEG C (medium-temperature) and 160-200 DEG C (low-temperature), and the energy consumption is only 25%-35% of that of the traditional process, so that the application has outstanding economic and environmental benefits.

[0024] 3、The basalt colored sand prepared by the application has bright color, uniform color, good weather resistance, wear resistance and chemical corrosion resistance, can effectively replace the use of traditional high-temperature colored sand, is not only suitable for colored stone metal tiles, but also can be widely applied to building wall decoration materials, ground anti-skid coating and other fields, and has good market application prospect.

[0025] 4、The application adopts electromagnetic heating straight-through type roller equipment to replace the traditional intermittent kiln, the temperature control precision and the degree of automation are high, the basalt colored sand preparation method provided by the application can be constructed as a continuous production process, is implemented on the electromagnetic heating assembly line production equipment, realizes the large-scale production of the colored sand, can effectively reduce the labor cost and material cost, and guarantees the quality and efficiency of the colored sand production. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The appearance comparison chart of the black basalt colored sand prepared in the embodiment 1 of the application before and after the acid resistance, alkali resistance and high temperature resistance performance test.

[0027] Figure 2 The appearance comparison chart of the blue basalt colored sand prepared in the embodiment 2 of the application before and after the acid resistance, alkali resistance and high temperature resistance performance test.

[0028] Figure 3 The appearance comparison chart of the red basalt colored sand prepared in the embodiment 3 of the application before and after the acid resistance, alkali resistance and high temperature resistance performance test.

[0029] Figure 4Appearance comparison chart of high-temperature ceramic red color sand prepared by a high-temperature melting process before and after acid resistance, alkali resistance and high-temperature resistance performance tests.

[0030] Figure 5 Appearance comparison chart of red basalt color sand prepared in Example 3 and Comparative Example 1 of the present application.

[0031] Figure 6 Appearance comparison chart of red basalt color sand prepared in Comparative Example 2 of the present application before and after acid resistance, alkali resistance and high-temperature resistance performance tests. DETAILED DESCRIPTION

[0032] The present application will be further described below in conjunction with the drawings and preferred embodiments, and the embodiments are only for illustrating the present application, but not for limiting the scope of the present application.

[0033] The materials, reagents and the like used in the following examples can be obtained from commercial channels unless otherwise specified; The methods in the following examples are conventional methods unless otherwise specified.

[0034] The present application provides a preparation method of basalt color sand, which comprises the following steps: taking basalt as a base material, coating a coloring binder and a color paste on the surface of the base material in sequence, heating the coated base material to 380-420 DEG C by electromagnetic heating, sintering, naturally cooling, uniformly coating a fixing liquid on the surface, heating to 160-200 DEG C by electromagnetic heating, sintering, and obtaining the basalt color sand.

[0035] The coloring binder is uniformly mixed by sodium silicate, a wetting agent and a dispersing agent; the wetting agent in each of the following examples is BYK-349 (main ingredient: polyether modified polysiloxane) for facilitating performance comparison; and the dispersing agent is BYK-191 (main ingredient: polyacrylic acid sodium salt).

[0036] The fixing liquid is uniformly mixed by fluorocarbon resin, acrylic resin, deionized water, a dispersing agent, a silane coupling agent, a leveling agent and a defoaming agent; the dispersing agent in each of the following examples is BYK-2050 (main ingredient: high molecular block copolymer containing an anchoring group); the silane coupling agent is KH-550 (ingredient: gamma-aminopropyl triethoxysilane); the leveling agent is BYK-333 (main ingredient: polyether modified polydimethylsiloxane); and the defoaming agent is BYK-024 (main ingredient: bubble breaking polymer solution in an organic solvent).

[0037] The color paste is a metal oxide inorganic pigment color paste, which is composed of metal oxide inorganic pigment, sodium silicate, dispersant, anti-settling agent and defoaming agent; in the following embodiments, the dispersant in the color paste is BYK-110 (main component: low molecular weight unsaturated carboxylic acid polymer); the anti-settling agent is BYK-410 (main component: modified urea solution); and the defoaming agent is BYK-021 (main component: defoaming polymer solution).

[0038] The same electromagnetic heating roller equipment with a length of 8 m is used in each of the following examples.

[0039] The continuous production process is used in each of the following examples.

[0040] The preparation method and application of the basalt colored sand are further described below in combination with specific examples.

[0041] Example 1 The present example provides a black basalt colored sand preparation method, which comprises the following steps: (1) Preparation of raw materials 1.1 Base material: 1 ton of 16-40 mesh black gray basalt sand particles; 1.2 Coloring binder: prepared according to the proportion of 90 parts of sodium silicate (density 1.20%, modulus M=3.0), 7 parts of wetting agent and 3 parts of dispersant, and prepared by stirring in a high-speed disperser at 1600 r / min for 35 min; 1.3 Color paste: carbon black is used as the metal oxide inorganic pigment, and prepared according to the proportion of 25 parts of carbon black (C), 70 parts of sodium silicate (density 1.30%, modulus M=3.0), 3 parts of dispersant, 1.2 parts of anti-settling agent and 0.8 parts of defoaming agent, and prepared by stirring in a high-speed disperser at 1600 r / min for 35 min; 1.4 Color fixing liquid: prepared according to the proportion of 43 parts of fluorocarbon resin, 29 parts of acrylic resin, 19 parts of deionized water, 2.5 parts of dispersant, 1.0 part of silane coupling agent, 0.8 part of leveling agent and 0.7 part of defoaming agent, and prepared by stirring in a high-speed disperser at 1620 r / min for 37 min.

[0042] (2) Production process steps 2.1 Surface coating: 1 ton of basalt sand particles is put into a horizontal stirrer, stirred at a speed of 900 r / min, and at the same time, 1.8% of the mass of the basalt sand particles, i.e. 18 kg, of the coloring binder is slowly added, and the stirring is continued for 19 min; 2.2 Coloring coating: then in the same stirrer, 3.5% of the mass of the basalt sand particles, i.e. 35 kg, of the color paste is slowly added at a speed of 900 r / min, and the stirring is continued for 37 min, until the sand material is uniformly coated in a wet state; 2.3 Medium temperature sintering: the colored wet sand is sent to an electromagnetic heating roller, the roller length is 8 m, the roller temperature is set to 400°C, the conveying screw speed is 45 r / min, and the roller speed is 40 r / min, and sintering is performed; when discharging, the sand temperature at the discharge port is monitored to be 305°C; 2.4 Medium temperature cooling: the sand is cooled using a water circulating condensation screw conveyor, and after being cooled to 95°C, it is conveyed to a horizontal mixer; 2.5 Color fixing coating: a spraying device with a nozzle diameter of 8 mm is arranged above the inlet of the horizontal mixer, and the sand entering the horizontal mixer is continuously sprayed with a color fixing liquid at a flow rate of 0.7 m / s, while the horizontal mixer is rotating at a speed of 900 r / min to stir the sprayed sand, so that the sand is in a uniform wet state; when the wet sand accumulates to a certain volume in the horizontal mixer , the discharge valve of the horizontal mixer is opened, and the sand is discharged; 2.6 Low temperature sintering: the wet sand is sent to an electromagnetic heating roller, the roller length is 8 m, the roller temperature is set to 180°C, the conveying screw speed is 45 r / min, and the roller speed is 38 r / min, and sintering is performed; during the discharging stage, the sand temperature at the discharge port is monitored, and the discharge temperature is measured to be 122°C; 2.7 Cooling and screening: the sand is cooled to 62°C using a vibrating screw conveyor, and then sent to a vibrating screen, and the black colored sand product with a particle size of 16-40 meshes is collected and packaged.

[0043] Example 2 The present embodiment provides a method for preparing blue basalt colored sand, comprising the following steps: (1) Preparation of raw materials 1.1 Base material: 1 ton of 16-40 mesh black gray basalt sand particles; 1.2 Colorant binder: prepared according to a ratio of 88 parts of sodium silicate (density 1.20%, modulus M=3.0), 8 parts of wetting agent, and 4 parts of dispersing agent, by stirring for 30 min at a speed of 1650 r / min in a high-speed disperser; 1.3 Color paste: cobalt blue (CoAl2O4) is used as a metal oxide inorganic pigment, and the color paste is prepared according to a ratio of 50 parts of cobalt blue, 40 parts of sodium silicate (density 1.30%, modulus M=3.0), 4 parts of dispersing agent, 5.2 parts of anti-settling agent, and 0.8 parts of defoaming agent, by stirring for 35 min at a speed of 1610 r / min in a high-speed disperser; 1.4 Fixing liquid: prepared by mixing fluorocarbon resin 46 parts, acrylic resin 29 parts, deionized water 20 parts, dispersing agent 2.5 parts, silane coupling agent 1.0 part, leveling agent 0.8 part, defoaming agent 0.7 part, and stirring for 35 min at 1570 r / min in a high-speed disperser.

[0044] (2) Production process steps 2.1 Surface coating: 1 ton of basalt sand particles is put into a horizontal stirrer, stirred at a speed of 900 r / min, and 2.0% of the mass of the basalt sand particles (i.e. 20 kg) of the coloring binder is slowly added, and the stirring is continued for 19 min; 2.2 Color coating: then in the same stirrer, at a speed of 900 r / min, 4.0% of the mass of the basalt sand particles (i.e. 40 kg) of the color paste is slowly added, and the stirring is continued for 36 min, until the sand is uniformly coated in a wet state; 2.3 Medium temperature sintering: the wet sand after coloring is sent to an electromagnetic heating roller, the roller length is 8 m, the roller temperature is set to 400℃, the conveying screw speed is 45 r / min, and the roller speed is 40 r / min, sintering is carried out, and the sand at the discharge port is monitored for temperature during the discharge stage, and the sand at the discharge port is measured to be 308℃; 2.4 Medium temperature cooling: the sand is cooled using a water-circulating condensing screw conveyor, and after cooling to 93℃, it is conveyed to a horizontal stirrer; 2.5 Fixing coating: a spraying device with a nozzle diameter of 8 mm is set above the feed inlet of the horizontal stirrer, and the sand entering the horizontal stirrer is continuously sprayed with fixing liquid at a flow rate of 0.8 m / s, while the horizontal stirrer stirs the sprayed sand entering at a speed of 900 r / min, so that the sand is in a uniform wet state; when the wet sand accumulates to the volume of the horizontal stirrer , the horizontal stirrer discharge valve is opened, and the sand is discharged; 2.6 Low temperature sintering: the wet sand is sent to an electromagnetic heating roller, the roller length is 8 m, the roller temperature is set to 180℃, the conveying screw speed is 45 r / min, and the roller speed is 38 r / min, sintering is carried out, and the sand at the discharge port is monitored for temperature during the discharge stage, and the discharge temperature is measured to be 126℃; 2.7 Cooling and screening: the sand is cooled to 65℃ using a vibrating screw conveyor, and then sent to a vibrating screen, and the blue colored sand product between 16-40 meshes is collected and packaged.

[0045] Example 3 The present embodiment provides a method for preparing red basalt colored sand, comprising the following steps: (1) Raw material preparation 1.1 Base material: 1 ton of 16-40 mesh black-gray basalt sand particles; 1.2 Color binding agent: prepared by mixing 90 parts of sodium silicate (density 1.20%, modulus M = 3.0), 7 parts of wetting agent, and 3 parts of dispersing agent at a ratio of 90:7:3, and stirring for 35 min at 1600 r / min in a high-speed disperser; 1.3 Color paste: prepared by mixing 35 parts of red iron oxide (Fe2O3) as a metal oxide inorganic pigment, 58 parts of sodium silicate (density 1.30%, modulus M = 3.0), 3 parts of dispersing agent, 3.2 parts of anti-settling agent, and 0.8 parts of defoaming agent at a ratio of 35:58:3:3.2:0.8, and stirring for 35 min at 1580 r / min in a high-speed disperser; 1.4 Color fixing liquid: prepared by mixing 46 parts of fluorocarbon resin, 29 parts of acrylic resin, 20 parts of deionized water, 2.5 parts of dispersing agent, 1.0 part of silane coupling agent, 0.8 part of leveling agent, and 0.7 part of defoaming agent at a ratio of 46:29:20:2.5:1.0:0.8:0.7, and stirring for 36 min at 1610 r / min in a high-speed disperser.

[0046] (2) Production process steps 2.1 Surface coating: 1 ton of basalt sand particles was put into a horizontal stirrer and stirred at a speed of 900 r / min, while slowly adding 1.9% of the mass of the basalt sand particles of the color binding agent (i.e. 19 kg), and continuously stirring for 18 min; 2.2 Color coating: then in the same stirrer, at a speed of 900 r / min, 3.5% of the mass of the basalt sand particles of the color paste (i.e. 35 kg) was slowly added, and continuously stirred for 36 min, until the sand material was uniformly coated in a wet state; 2.3 Medium temperature sintering: the wet sand material after coloring was sent to an electromagnetic heating roller, the roller length was 8 m, the roller temperature was set to 400℃, the conveying screw speed was 45 r / min, and the roller speed was 40 r / min, sintering was carried out, and when discharging, the sand material at the discharge port was monitored, and the discharge temperature was measured to be 310℃; 2.4 Medium temperature cooling: the sand material was cooled using a water circulating condensation screw conveyor, and after cooling to 92℃, it was conveyed to a horizontal stirrer; 2.5 Color fixing coating: a spraying device with a nozzle diameter of 8 mm was set above the feed inlet of the horizontal stirrer, and the sand material entering the horizontal stirrer was continuously sprayed with the color fixing liquid at a flow rate of 0.7 m / s, while the horizontal stirrer stirred the sprayed sand material at a speed of 900 r / min, so that the sand material was in a uniform wet state; when the wet sand material accumulated to the volume of the horizontal stirrer , the discharge valve of the horizontal stirrer was opened, and the material was discharged; 2.6 Low-temperature sintering: The wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set to 180℃, the conveying screw speed is 45 r / min, and the roller speed is 38 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the discharge temperature of the sand is 131℃. 2.7 Cooling and Screening: The sand is cooled to 67°C using a vibrating screw conveyor and sent to a vibrating screen to collect red colored sand products with a mesh size of 16-40 and package them.

[0047] Example 4 This embodiment provides a method for preparing green basalt colored sand, including the following steps: (1) Raw material preparation 1.1 Base material: 1 ton of 16-40 mesh dark gray basalt sand; 1.2 Coloring binder: Prepared by mixing sodium silicate (density 1.20%, modulus M=3.0) 92 parts, wetting agent 8 parts, and dispersant 4 parts in a high-speed disperser at 1600 r / min for 35 min; 1.3 Pigment: Using chrome green (Cr2O3) as the inorganic pigment of metal oxide, it was prepared by mixing chrome green (Fe2O3) 50 parts, sodium silicate (density 1.30%, modulus M=3.0) 70 parts, dispersant 5 parts, anti-settling agent 5 parts and defoamer 1 part in a high-speed disperser at 1580 r / min for 35 min. 1.4 Fixing solution: Prepared by mixing 50 parts of fluorocarbon resin, 20 parts of acrylic resin, 22 parts of deionized water, 2 parts of dispersant, 1.5 parts of silane coupling agent, 0.5 parts of leveling agent and 0.5 parts of defoamer in a high-speed disperser at 1610 r / min for 36 min.

[0048] (2) Production process steps 2.1 Surface coating: 1 ton of basalt sand particles are put into a horizontal mixer and stirred at a speed of 900 r / min. At the same time, 2.0% of the mass of the basalt sand particles (i.e., 20 kg) of coloring binder is slowly added and stirred for 18 min. 2.2 Coloring and Coating: Then, in the same mixer, at a speed of 900 r / min, slowly add 5.0% (i.e., 50 kg) of color paste, which accounts for 5.0% of the mass of basalt sand particles, and continue stirring for 36 min until the sand is evenly coated and wetted. 2.3 Medium-temperature sintering: The colored wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set at 420℃, the conveying screw speed is 45 r / min, and the roller speed is 40 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the discharge temperature is 315℃. 2.4 Medium-temperature cooling: The sand is cooled to 92°C using a water-circulating condensing screw conveyor and then conveyed to a horizontal mixer. 2.5 Fixing and Coating: Fixing liquid is continuously sprayed onto the sand entering the horizontal mixer at a flow rate of 1.0 m / s through a spraying device with a nozzle diameter of 8 mm, positioned above the feed inlet of the horizontal mixer. Simultaneously, the horizontal mixer rotates at 900 r / min to agitate the sprayed sand, ensuring it is uniformly wetted. The wetted sand is then accumulated in the horizontal mixer. When discharging, open the discharge valve of the horizontal mixer to discharge the material; 2.6 Low-temperature sintering: The wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set to 220℃, the conveying screw speed is 60 r / min, and the roller speed is 35 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the discharge temperature of the sand is 130℃. 2.7 Cooling and Screening: The sand is cooled to 67°C using a vibrating screw conveyor and sent to a vibrating screen to collect green colored sand products with a mesh size of 16-40 and package them.

[0049] Example 5 This embodiment provides a method for preparing yellow basalt colored sand, including the following steps: (1) Raw material preparation 1.1 Base material: 1 ton of 16-40 mesh dark gray basalt sand; 1.2 Coloring binder: Prepared by mixing sodium silicate (density 1.20%, modulus M=3.0) 88 parts, wetting agent 6 parts, and dispersant 2 parts in a high-speed disperser at 1600 r / min for 35 min; 1.3 Pigment: Zinc iron yellow (ZnFe2O4) was used as the inorganic pigment of metal oxide. It was prepared by mixing 20 parts of zinc iron yellow (ZnFe2O4), 40 parts of sodium silicate (density 1.30%, modulus M=3.0), 2 parts of dispersant, 2 parts of anti-settling agent, and 0.5 parts of defoamer in a high-speed disperser at 1580 r / min for 35 min. 1.4 Fixing solution: Prepared by mixing 40 parts of fluorocarbon resin, 30 parts of acrylic resin, 25 parts of deionized water, 3 parts of dispersant, 2 parts of silane coupling agent, 1 part of leveling agent and 1 part of defoamer in a high-speed disperser at 1610 r / min for 36 min.

[0050] (2) Production process steps 2.1 Surface coating: 1 ton of basalt sand particles are put into a horizontal mixer and stirred at a speed of 900 r / min. At the same time, 1.5% of the mass of the basalt sand particles (i.e., 15 kg) of coloring binder is slowly added and stirred for 18 min. 2.2 Coloring and Coating: Then, in the same mixer, at a speed of 900 r / min, slowly add 2.0% (i.e., 20 kg) of color paste, which accounts for 2.0% of the mass of basalt sand particles, and continue stirring for 36 min until the sand is evenly coated and wetted. 2.3 Medium-temperature sintering: The colored wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set at 380℃, the conveying screw speed is 45 r / min, and the roller speed is 40 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the sand discharge temperature is measured to be 300℃. 2.4 Medium-temperature cooling: The sand is cooled to 92°C using a water-circulating condensing screw conveyor and then conveyed to a horizontal mixer. 2.5 Fixing and Coating: Fixing liquid is continuously sprayed onto the sand entering the horizontal mixer at a flow rate of 0.5 m / s through a spraying device with a nozzle diameter of 8 mm, positioned above the feed inlet of the horizontal mixer. Simultaneously, the horizontal mixer rotates at 900 r / min to agitate the sprayed sand, ensuring the sand is uniformly wetted. The wetted sand is then accumulated in the horizontal mixer. When discharging, open the discharge valve of the horizontal mixer to discharge the material; 2.6 Low-temperature sintering: The wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set to 180℃, the conveying screw speed is 45 r / min, and the roller speed is 40 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the sand discharge temperature is measured to be 120℃. 2.7 Cooling and Screening: The sand is cooled to 67°C using a vibrating screw conveyor and sent to a vibrating screen to collect yellow sand products with a mesh size of 16-40 and package them.

[0051] Comparative Example 1 This comparative example provides a red basalt colored sand, which differs from Example 3 in that no coloring binder was added during the preparation process.

[0052] The preparation method of the basalt colored sand is carried out according to the following steps: S1. Coloring and coating: Put 1 ton of 16-40 mesh basalt sand into a horizontal mixer and stir at a speed of 900 r / min. Slowly add 3.5% (i.e., 35 kg) of color paste, which accounts for 3.5% of the mass of the basalt sand, and continue stirring for 36 min until the sand is evenly coated and wetted. S2. Medium-temperature sintering: The colored wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set to 400℃, the conveying screw speed is 45 r / min, and the roller speed is 40 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the sand discharge temperature is measured to be 310℃. S3, Medium-temperature cooling: The sand is cooled to 92°C using a water-circulating condensing screw conveyor and then conveyed to the horizontal mixer. S4. Fixing and Coating: Fixing liquid is continuously sprayed onto the sand entering the horizontal mixer at a flow rate of 0.7 m / s through a spraying device with a nozzle diameter of 8 mm, positioned above the feed inlet of the horizontal mixer. Simultaneously, the horizontal mixer rotates at 900 r / min to agitate the sprayed sand, ensuring it is uniformly wetted. The wetted sand is then accumulated in the horizontal mixer. When discharging, open the discharge valve of the horizontal mixer to discharge the material; S5. Low-temperature sintering: The wet sand is fed into an electromagnetic heating roller with a length of 8 m. The roller temperature is set to 180℃, the conveying screw speed is 45 r / min, and the roller speed is 38 r / min for sintering. During the discharge stage, the temperature of the sand at the discharge port is monitored and the sand discharge temperature is measured to be 130℃. S6. Cooling and screening: The sand is cooled to 63°C using a vibrating screw conveyor and sent to a vibrating screen to collect red colored sand products between 16 and 40 mesh and package them.

[0053] Apart from the differences mentioned above, the composition and content of the color paste and the fixing solution are the same as in Example 3, and will not be repeated here.

[0054] Comparative Example 2 This comparative example provides a red basalt colored sand, which differs from Example 3 in that no color-fixing liquid was added during the preparation process.

[0055] The preparation method of the basalt colored sand is carried out according to the following steps: S1. Surface coating: Put 1 ton of 16-40 mesh basalt sand into a horizontal mixer and stir at a speed of 900 r / min. At the same time, slowly add 1.9% of the mass of the basalt sand (i.e., 19 kg) of coloring binder and continue stirring for 18 min. S2. Coloring and coating: Then, in the same mixer, slowly add 3.5% (i.e., 35 kg) of color paste, which accounts for 3.5% of the mass of basalt sand particles, at a speed of 900 r / min, and continue stirring for 36 min until the sand is evenly coated and wetted. S3, medium-temperature sintering: The colored wet sand is fed into the electromagnetic heating roller. The conveying screw speed is 45 r / min, the roller temperature is set to 400℃, the conveying screw speed is 45 r / min, the roller speed is 40 r / min, and sintering is carried out. During the discharge stage, the temperature of the sand at the discharge port is monitored and the sand discharge temperature is measured to be 310℃. S4. Cooling and screening: The sand is cooled to 68°C using a vibrating screw conveyor and sent to a vibrating screen to collect red colored sand products with a mesh size of 16-40 and package them.

[0056] Apart from the differences mentioned above, the composition and content of the coloring binder and color paste are the same as in Example 3, and will not be repeated here.

[0057] Performance testing This invention selects basalt colored sand prepared in Examples 1-3 for performance testing to provide a representative illustration of the performance of colored sand prepared by the basalt colored sand preparation method provided by this invention. Each sample underwent water resistance, acid resistance, alkali resistance, and high-temperature resistance tests, and the performance was compared with that of Comparative Examples 1-2 and commercially available high-temperature ceramic red colored sand (mesh size also between 16 and 40 mesh) prepared by a high-temperature melting process. The test results are as follows: Figures 1-6 As shown in Table 1, the test process and results are summarized in the table.

[0058] Table 1 Performance test results of Examples 1-3, Comparative Examples 1 and 2, and commercially available high-temperature colored sand

[0059] As shown in Table 1, the colored sand prepared by Examples 1-3 directly on basalt sand grains according to the present invention using the "three-step coating and medium-low temperature segmented sintering" process meets the unique index requirements of colored stone metal tiles and has the same performance and effect as commercially available ceramic colored sand.

[0060] Comparison of Example 1 and Example 3 is shown in the figure below. Figure 5 As shown, the results indicate that adding a coloring binder can pre-agglomerate or clump the dust adsorbed on the surface of the basalt raw material, preventing the dust from mixing with liquid B color paste and causing uneven distribution of the color paste. This ensures uniform coloring of the colored sand.

[0061] Comparative Example 2 compared to Example 3: Adding a color-fixing liquid to coat and encapsulate the sand material can reduce the pH value of the colored sand using sodium silicate as a coloring binder, and the main component, fluorocarbon resin, can further improve its acid and alkali resistance and weather resistance.

[0062] Therefore, the above results show that the colored sand prepared by the basalt colored sand preparation method provided by the present invention can fully meet the requirements of colored stone metal tiles, with bright and uniform colors, and good wear resistance and acid and alkali resistance.

[0063] The preparation method of this invention is simple, efficient, green and environmentally friendly. A comparison with the traditional high-temperature colored sand preparation process is shown in Table 2. Compared with the traditional high-temperature colored sand process, the preparation method of this invention reduces energy consumption by 25% to 35%, greatly reducing production costs. Moreover, the energy is clean and meets the requirements of green environmental protection. In terms of product performance, it also significantly improves chemical resistance and weather resistance, increases product toughness, and retains the natural edges and corners of basalt, resulting in a strong appearance, color and texture of the finished colored stone metal tile. It can effectively replace the traditional high-temperature sintering process of colored sand.

[0064] Table 2. Comprehensive Comparative Analysis of Examples 1-5 with Commercially Available High-Temperature Ceramic Colored Sand and its Preparation Process

Claims

1. A method for preparing basalt colored sand, using basalt as a base material, characterized in that, A coloring binder and a color paste are sequentially coated on the surface of the base material. The coated base material is then sintered in a heating environment of 380~420℃. After cooling, a fixing liquid is uniformly coated on the surface. The base material coated with the fixing liquid is then sintered in a heating environment of 160~200℃ to obtain the basalt colored sand. The coloring binder is composed of sodium silicate, wetting agent and dispersant uniformly mixed; the fixing liquid is composed of fluorocarbon resin, acrylic resin, deionized water, dispersant, silane coupling agent, leveling agent and defoamer uniformly mixed; and the color paste is a metal oxide inorganic pigment color paste.

2. The method for preparing basalt colored sand according to claim 1, characterized in that, All sintering is carried out using electromagnetically heated rollers.

3. The method for preparing basalt colored sand according to claim 2, characterized in that, A horizontal mixer was used to coat the base material surface with coloring binder, color paste, and fixing liquid respectively.

4. The method for preparing basalt colored sand according to claim 3, characterized in that, The specific steps include the following: S1. Basalt sand particles with a mesh size between 16 and 40 are put into a horizontal mixer. A coloring binder accounting for 1.5 to 2% of the mass of the basalt sand particles is added and thoroughly mixed with the basalt sand particles. Then, a color paste accounting for 2.0 to 5.0% of the mass of the basalt sand particles is added and thoroughly mixed again to obtain sand particles with a surface coated with color paste. S2. The sand particles coated with color paste on the surface are conveyed into the electromagnetic heating roller for sintering. The temperature of the electromagnetic heating roller is set to 380~420℃. The speed of the conveying screw and the roller is adjusted according to the length of the electromagnetic heating roller to control the residence time of the sand particles. When the discharge temperature of the sand particles is not less than 300℃, the material is discharged. S3. Cool the sand particles processed in step S2 to below 100°C, and then feed them into a horizontal mixer. Spray a fixing liquid evenly onto the surface of the sand particles at a flow rate of 0.5~1.0 m / s to obtain sand particles with a surface coated with fixing liquid. S4. The sand particles coated with the color-fixing liquid are conveyed into the electromagnetic heating roller for sintering. The temperature of the electromagnetic heating roller is set to 160~200℃. The speed of the conveying screw and the roller is adjusted according to the length of the electromagnetic heating roller to control the residence time of the sand particles. When the discharge temperature of the sand particles reaches 100~150℃, the material is discharged. The obtained material is cooled and screened to obtain the basalt colored sand.

5. The method for preparing basalt colored sand according to claim 4, characterized in that, In step S2, the length of the electromagnetic heating roller is 8 m, the conveying screw speed is set to 45 r / min, and the roller speed is set to 40 r / min.

6. The method for preparing basalt colored sand according to claim 4, characterized in that, In step S4, the length of the electromagnetic heating roller is 8 m, the conveying screw speed is set to 45~60 r / min, and the roller speed is set to 35~40 r / min.

7. The method for preparing basalt colored sand according to claim 1, characterized in that, The mass fractions of each component in the coloring adhesive are as follows: sodium silicate 88-92 parts, wetting agent 6-8 parts, and dispersant 2-4 parts.

8. The method for preparing basalt colored sand according to claim 1, characterized in that, The mass fractions of each component in the fixing solution are as follows: 40-50 parts of fluorocarbon resin, 20-30 parts of acrylic resin, 20-25 parts of deionized water, 2-3 parts of dispersant, 1-2 parts of silane coupling agent, 0.5-1 part of leveling agent, and 0.5-1 part of defoamer.

9. The method for preparing basalt colored sand according to claim 1, characterized in that, The metal oxide inorganic pigment paste comprises the following components in parts by weight: 20-50 parts of metal oxide inorganic pigment, 40-70 parts of sodium silicate, 2-5 parts of dispersant, 2-5 parts of anti-settling agent, and 0.5-1 part of defoamer; the metal oxide inorganic pigment is one or more of iron oxide red, cobalt blue, zinc iron yellow, carbon black, and chrome green.

10. The basalt colored sand prepared by the method described in any one of claims 1 to 9 is applied to the preparation of colored stone metal tiles.

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