CN109052970B - Method for preparing functional glass ceramics by directly sintering asbestos tailings - Google Patents
Method for preparing functional glass ceramics by directly sintering asbestos tailings Download PDFInfo
- Publication number
- CN109052970B CN109052970B CN201811318321.0A CN201811318321A CN109052970B CN 109052970 B CN109052970 B CN 109052970B CN 201811318321 A CN201811318321 A CN 201811318321A CN 109052970 B CN109052970 B CN 109052970B
- Authority
- CN
- China
- Prior art keywords
- asbestos tailings
- phase
- heating
- microcrystalline glass
- sintering
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C10/00—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition
- C03C10/0063—Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition containing waste materials, e.g. slags
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/06—Other methods of shaping glass by sintering, e.g. by cold isostatic pressing of powders and subsequent sintering, by hot pressing of powders, by sintering slurries or dispersions not undergoing a liquid phase reaction
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
- C03C1/002—Use of waste materials, e.g. slags
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Geochemistry & Mineralogy (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Dispersion Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Ceramic Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Glass Compositions (AREA)
Abstract
The invention provides a method for preparing microcrystalline glass by directly sintering asbestos tailings. The method comprises the following steps: pretreating the asbestos tailings and the ingredients, or pretreating the asbestos tailings to obtain biscuit powder; pressing and molding the biscuit powder to obtain a blank; and heating the blank body to 750-900 ℃, preserving heat to promote nucleation and crystallization of the blank body, then heating to 1100-1250 ℃, sintering, and cooling after sintering to obtain the microcrystalline glass. The beneficial effects of the invention can include: the utilization rate of the asbestos tailings can reach 90-100%, the process flow is simple, the energy consumption is low, the environment is protected, the industrial popularization is facilitated, and the prepared microcrystalline glass has excellent performance and high added value.
Description
Technical Field
The invention relates to the field of solid waste treatment and resource utilization, in particular to a method for preparing functional glass ceramics by using asbestos tailings.
Background
The asbestos tailings are tailings generated in the process of mining and dressing chrysotile (chrysotile asbestos) ores, the main phase of the asbestos tailings is serpentine, and the asbestos tailings also contain a small amount of non-serpentine symbiotic or associated minerals. Because the chrysotile ore has a low cotton content of about 5-10% (the content of western mines is about 5-7%), currently 1 ton of chrysotile asbestos is produced to produce about 20-30 tons of tailings, and parts of areas are even higher, however, the utilization rate of chrysotile asbestos tailings in China is low as a whole, and the accumulation amount of chrysotile asbestos tailings is about 5 hundred million tons due to historical accumulation. The large accumulation of the asbestos tailings not only occupies a large amount of land, but also causes resource waste, and because asbestos is a carcinogenic substance (has a nanofiber structure), the asbestos has serious harm to the environment and human bodies. At present, the national full advocates to construct a resource-saving and environment-friendly society, and the asbestos tailings are not industrially developed and utilized all the time. At present, the environment-friendly and resource-saving industrialized integrated innovation technology with high efficiency and high added value utilization needs to be searched and researched urgently.
The microcrystalline glass, also known as glass ceramic and microcrystalline ceramic, is a kind of polycrystalline material in which the microcrystalline phase and glass phase coexist, which is obtained by controlling heat treatment system based on glass and ceramic forming technology, and can be used as high-grade building decorative material and various functional materials, etc. because of its good mechanical property, high hardness, high wear resistance and acid-base corrosion resistance.
The existing microcrystalline glass production process mainly comprises the following steps: the main production processes of the integral crystallization method, the melt sintering method and the sol-gel method are the first two for the industrial waste residue microcrystalline glass. The production flow of the integral crystallization method is mixing → high temperature melting → pouring molding → annealing → nucleation and crystallization → polishing and trimming → product, and the production flow of the melting and sintering method is mixing → high temperature melting → water quenching → ball milling → tabletting → nucleation and crystallization → polishing and trimming → product. The integral crystallization method and the melt sintering method both comprise a high-temperature melting process, and both require a secondary high-temperature treatment process, so that the defects or defects of high energy consumption, long process flow, complicated working procedures, low utilization rate of industrial waste residues and the like exist. In addition, from the existing research situation, the microcrystalline glass prepared by adopting industrial solid waste is generally used as a structural material, so research focuses mainly on how to improve the mechanical property, but research on functionalization is few, and the added value of the product is low, thereby limiting the commercialization of the microcrystalline glass.
In conclusion, the existing mainstream production process for preparing the microcrystalline glass by using the asbestos tailings, namely the integral crystallization method and the melt sintering method, has the problems of high production energy consumption, long process flow, low waste residue utilization rate and the like, and the research on preparing the functionalized magnetic microcrystalline glass by using the asbestos tailings is not facilitated at present, so that the product is difficult to realize high added value utilization.
Disclosure of Invention
In view of the deficiencies in the prior art, it is an object of the present invention to address one or more of the problems in the prior art as set forth above. For example, one of the objectives of the present invention is to provide a method for preparing functional glass ceramics by directly sintering asbestos tailings, so as to efficiently utilize asbestos tailings, especially asbestos tailings.
In order to achieve the above objects, one aspect of the present invention provides a method for preparing functional glass ceramics by directly sintering asbestos tailings. The method may comprise the steps of: crushing and drying asbestos tailings to obtain biscuit powder; pressing and molding the biscuit powder to obtain a blank; and heating the blank to 750-900 ℃, preserving heat to promote nucleation and crystallization of the blank, then heating to 1100-1250 ℃, sintering, and cooling after sintering to obtain the microcrystalline glass.
The invention also provides a method for preparing the functional glass ceramics by directly sintering the asbestos tailings. The method may comprise the steps of: pretreating raw materials to obtain biscuit powder, wherein the raw materials comprise asbestos tailings and ingredients, the mass ratio of the asbestos tailings in the raw materials is more than 90%, and the ingredients comprise fluxing agent and/or microcrystalline glass component replenisher; pressing and molding the biscuit powder to obtain a blank; and heating the blank to 750-900 ℃, preserving heat to promote nucleation and crystallization of the blank, then heating to 1100-1250 ℃, sintering, and cooling after sintering to obtain the microcrystalline glass. .
According to one or more exemplary embodiments of the present invention, the ingredients may include: at least one of industrial caustic soda, potash feldspar, nepheline, perlite, waste glass, borax, polishing and trimming waste. .
According to one or more exemplary embodiments of the invention, the asbestos tailings may comprise chrysotile asbestos tailings.
According to one or more exemplary embodiments of the invention, the green body powder may have a particle size below 80 μm.
According to one or more exemplary embodiments of the present invention, the press-forming may include: uniformly and flatly paving the biscuit powder in a mould, maintaining the pressure for 10-60 s under the pressure of 20-100 MPa, and then demoulding to obtain a blank.
According to one or more exemplary embodiments of the present invention, the green body is heated to 750-950 ℃ at a heating rate of 5-10 ℃/min.
According to one or more exemplary embodiments of the present invention, the reheating is performed to 1100 to 1250 ℃ at a temperature increase rate of 3 to 5 ℃/min.
According to one or more exemplary embodiments of the present invention, the holding time after heating to 750 to 950 ℃ is 30 to 60 min; and after heating to 1100-1250 ℃, preserving heat for 30-90 min.
According to one or more exemplary embodiments of the present invention, the obtained glass ceramics are trimmed and/or polished, and waste materials generated by trimming and/or polishing are returned to be used for manufacturing the biscuit powder.
According to one or more exemplary embodiments of the present invention, the waste material is present in the feedstock at a mass fraction of less than 2%.
Compared with the prior art, the invention has the beneficial effects that: the method solves the problem that the asbestos tailings are difficult to be recycled, and the utilization rate of the asbestos tailings can reach 90-100%; the method has the advantages of simple process flow, low energy consumption, environmental protection and contribution to industrial popularization, and the prepared microcrystalline glass has good performance and high added value.
Drawings
The above and other objects and features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:
fig. 1 shows a schematic flow diagram of a method for preparing functional glass-ceramics by directly sintering asbestos tailings according to an exemplary embodiment of the present invention;
fig. 2 shows a schematic flow diagram of a method for preparing functional glass-ceramics by directly sintering asbestos tailings according to another exemplary embodiment of the present invention;
FIG. 3 shows an X-ray diffraction pattern of a sample of functional glass-ceramic in example 1;
FIG. 4 shows a scanning electron micrograph of a functional glass-ceramic sample in example 1;
FIG. 5 shows a hysteresis loop plot of functional glass-ceramics in example 1;
FIG. 6 shows an X-ray diffraction pattern of a sample of functional glass-ceramic in example 2;
FIG. 7 shows a scanning electron micrograph of a functional glass-ceramic sample in example 2;
FIG. 8 shows a hysteresis loop plot of functional glass-ceramics in example 2;
FIG. 9 shows an X-ray diffraction pattern of a functional crystallized glass sample of example 3;
FIG. 10 shows a scanning electron micrograph of a functional glass-ceramic sample in example 3;
fig. 11 shows a hysteresis loop plot of functional glass-ceramics in example 3;
FIG. 12 shows an X-ray diffraction pattern of a functional crystallized glass sample of example 4;
FIG. 13 shows a scanning electron micrograph of a functional glass-ceramic sample according to example 4;
FIG. 14 shows a hysteresis loop plot of functional glass-ceramics in example 4;
FIG. 15 shows an X-ray diffraction pattern of a functional crystallized glass sample of example 5;
FIG. 16 shows a scanning electron micrograph of a functional glass-ceramic sample in example 5;
fig. 17 shows a hysteresis loop plot of the functional glass-ceramic of example 5.
Detailed Description
Hereinafter, the method for preparing functional glass ceramics by directly sintering asbestos tailings according to the present invention will be described in detail with reference to the accompanying drawings and exemplary embodiments.
At present, the asbestos tailings in China are large in accumulation amount and low in utilization rate, so that a large amount of land is occupied, and due to carcinogenicity of asbestos, the asbestos tailings also form serious harm to the environment and human bodies. Therefore, the asbestos tailings are urgently needed to be comprehensively and environmentally utilized with high added value.
Therefore, the invention provides a method for preparing functional glass ceramics by using raw materials containing asbestos tailings.
In an exemplary embodiment of the invention, the method may comprise the steps of:
the asbestos tailings are used as raw materials, or the asbestos tailings and auxiliary materials are used as raw materials, and the raw materials are pretreated to obtain bisque powder with the granularity not greater than 80 microns, as shown in step S01 in figure 1. When the raw material only comprises asbestos tailings, the pretreatment can comprise crushing and drying; when the raw material comprises asbestos tailings and ingredients, the pretreatment can comprise drying, crushing, mixing and the like. Wherein, the crushing can comprise crushing and grinding; further, the pretreatment after grinding, the pulverization may further include a step of particle size classification. The mass ratio of the asbestos tailings in the raw materials is more than 90%, so that the requirement of high utilization rate of the asbestos tailings can be met. The granularity of the biscuit powder can be further controlled to be 10-80 mu m, which is not only beneficial to the forming of a blank body, but also beneficial to the improvement of the performance of a sample; if the particle size is larger than 80 mu m, the limitation can affect the sintering reaction, thereby reducing the compactness of the product microcrystalline glass; if the particle size of the powder is less than 10 mu m, deep processing is required, and the energy consumption is high. The water content in the biscuit powder can be 1.2-3.5% (mass fraction), the water content of the mass fraction can play a part of bonding role in the pressing process of the biscuit powder, but the excessively high water content is not favorable for the compactness of a finally fired sample.
And (4) pressing and molding the biscuit powder to obtain a microcrystalline glass blank, as shown in step S02 in figure 1. The step of press forming may comprise: uniformly spreading the biscuit powder in a forming grinding tool, maintaining the pressure for 10-60 s under the pressure of 20-100 MPa, and then demoulding to obtain a blank. If the pressure is too high, the biscuit is easy to crack and difficult to form; if the pressure is too low, the bonding effect among the particles is poor, and the number of gaps is large; and the pressure maintaining time is long, the pores of the internal structure of the blank are small, but the energy consumption is increased, and the cost is influenced. Furthermore, in the compression molding process, the pressure can be maintained at 40-80 MPa, for example, the pressure can be controlled at 50 or 70MPa, and the time can be controlled at 20 or 50 s. Wherein, the environmental condition of the blank manufacturing can be room temperature, or the temperature slightly higher than the room temperature, such as 30-100 ℃.
And heating the green body to 750-900 ℃ (which can be called as a low-temperature stage) and preserving heat to promote the nucleation and crystallization of the green body, namely decomposing, oxidizing and reconstructing a phase of the green body to form a new stable phase. For example, the heating can be carried out to 820 +/-30 ℃; and then heating to 1100-1250 ℃ (which can be called high temperature stage) for sintering, for example heating to 1160 +/-50 ℃, and cooling after sintering is completed to obtain the microcrystalline glass, as shown in step S03 in FIG. 1. The temperature of the low-temperature stage is controlled to be 750-900 ℃, if the temperature is too high, crystals grow too much, and the densification bonding state among the crystals is damaged, so that the structural performance of the microcrystalline glass is influenced; if the temperature is too low, the crystallization is insufficient, so that the content of a crystalline phase is reduced, and the structural performance of the microcrystalline glass is influenced. The temperature in the high-temperature stage is controlled to be 1100-1250 ℃, and if the temperature is too high, the microcrystalline glass is over-burnt, and defects such as bubbles and cracks appear; if the temperature is too low, the microcrystalline glass is not completely sintered, and the compactness is affected.
In this embodiment, further, a small amount of binder may be added in the process of preparing the biscuit powder, so as to facilitate the integrity and uniformity of the biscuit after tabletting (i.e. compression molding). The addition amount of the binder can be 3-5% of the mass of the dried raw materials. The binder may include: an aqueous solution of one of starch, polyvinyl alcohol and carboxymethyl cellulose.
In the embodiment, no granulating agent is required to be added, the raw material can be pressed and molded under a drier condition (with little water content or little binder content), the powder is easy to flow under the drier condition, and the filler is easy to control and uniform in the tabletting process, so that the granulating treatment is not required, and the generation of high energy consumption is avoided.
In this embodiment, the batch materials may include fluxing agents and/or microcrystalline glass composition extenders. Among them, the flux may include: at least one of industrial caustic soda, potash feldspar, waste glass, borax and perlite. The microcrystalline glass composition extender may comprise: at least one of nepheline, polishing and trimming scrap.
In this embodiment, the ingredients may include: at least one of industrial caustic soda, potash feldspar, nepheline, perlite, waste glass, borax, polishing and trimming waste. The addition of ingredients is a more preferable choice, for example, the ingredients not only can play a role of fluxing, but also can provide a liquid phase under a high-temperature condition to promote compact sintering of a green body, and can supplement components.
The raw materials can comprise the following components in percentage by mass: 0-10% of caustic soda, 0-7% of potash feldspar, 0-5% of nepheline, 0-10% of perlite, 0-10% of waste glass and 0-5% of borax.
In this embodiment, the asbestos tailings may include chrysotile asbestos tailings, which may include the following components in mass percent:
36～50％MgO、35～50％SiO2、5～20％Fe2O3、3～10％CaO、0.5～1.2％Al2O3、0.2～0.8％Cr2O3、0.2～0.5％NiO、0.1～0.3％K2O、0.1～0.2％MnO、0.02～0.08％BaO、0.01～0.05％Co3O4the balance may be loss on ignition, for example, the loss on ignition may be 2.46 to 15.65%.
In this embodiment, the chrysotile asbestos tailings) may have a water content of 5 to 20%, and after drying, the asbestos tailings (or raw materials) may have a water content of 1.2 to 3.5%.
Because the fibrous structure of the chrysotile in the asbestos tailings is difficult to grind, the chrysotile must be dried in the pretreatment, so that the fibrous structure of the chrysotile is damaged and converted into a non-chrysotile structure. The drying can include low-temperature roasting dehydration, specifically, the asbestos tailings are subjected to heat preservation at the temperature of 600-750 ℃ so that the serpentine in the asbestos tailings is subjected to dehydration reaction to form forsterite, and the fiber structure in the asbestos tailings can be destroyed after the forsterite formed by low-temperature roasting dehydration, so that the subsequent grinding, press forming and final firing effects are facilitated, for example, the compactness is better. According to the thermal analysis curve of the asbestos tailings, the serpentine has a wide and wide endothermic valley between 600 ℃ and 750 ℃, and the serpentine is correspondingly subjected to a dehydration reaction to form forsterite. The heat preservation time can be 30-90 min, further 40-70 min, for example 50 min.
Before drying the asbestos tailings, the large asbestos tailings can be primarily crushed; to ensure complete and sufficient dehydration of the asbestos tailings. After drying, the asbestos tailings may be crushed a second time.
In this embodiment, the ingredients may not be dried, and the tailings may be uniformly mixed with the ingredients and crushed after dehydration.
In this embodiment, in the low temperature stage, if the temperature rising rate is too high, the crystallization of the blank is insufficient, and the structural performance of the final glass-ceramic is affected, and if the temperature rising rate is too low, the crystallization is facilitated, but the time is long, and the energy consumption is high. Therefore, the blank can be heated to 750-950 ℃ at a heating rate of 5-10 ℃/min, for example, the heating rate can be 7 +/-1 ℃.
The heat preservation time after heating to 750-950 ℃ can be 30-60 min; if the time is too long, crystals grow too long, and the densification bonding state among the crystals is damaged, so that the structural performance of the microcrystalline glass is influenced; if the time is too short, the crystallization is insufficient, so that the content of the crystalline phase is reduced, and the structural performance of the glass ceramics is affected. Therefore, the heat preservation time can be controlled within 30-60 min, further 45-55 min, such as 50 + -2 min.
In this embodiment, in the high temperature stage, if the temperature rise rate is too high, the densification effect will be affected, and at the same time, the microcrystalline glass sample is likely to crack, and if the temperature rise rate is too low, sintering is facilitated, but the energy consumption is high. Therefore, the blank body can be reheated to 1100-1250 ℃ at a heating rate of 3-15 ℃/min, and further, the heating rate can be 3-5 ℃/min, for example, 4 ℃/min.
After heating to 1100-1250 ℃, the temperature can be preserved for 30-90 min so as to ensure that the sintering is complete. If the time is too long, the energy consumption is high although the microcrystalline glass is favorable for densification; if the time is too short, the microcrystalline glass is not completely sintered, the densification is not high, and the structural performance of the microcrystalline glass product is not facilitated. Therefore, the heat preservation time can be controlled within 30-90 min, further 45-75 min, such as 60 + -5 min.
In this embodiment, the step of cooling may include: slow cooling to room (or ambient) temperature, e.g., with furnace temperature. The slow cooling step may further include: slow cooling to below 250 ℃, e.g. 200 ℃; rapid cooling may then be performed. Wherein, the slow cooling temperature can be controlled to be 5-10 ℃/min, and the fast cooling rate can be controlled to be 20-38 ℃/min.
In this embodiment, the heat treatment process (i.e., the sintering process) may be performed in an oxygen-containing gas, such as air or an oxygen-rich gas. The heat treatment process may be performed in a tunnel kiln.
In this embodiment, the method may further include the steps of: the obtained microcrystalline glass is subjected to edge cutting and/or polishing, and the waste obtained in the step is returned to be used as one of the raw materials; the mass ratio of the waste in the raw materials can be 0-2%. The cooling water generated by polishing and trimming can be recycled after precipitation.
In another exemplary embodiment of the invention, as shown in fig. 2, after the asbestos tailings and the ingredients are pretreated, the asbestos tailings and the ingredients are weighed, matched and mixed uniformly to obtain microcrystalline glass biscuit powder; spreading the microcrystalline glass biscuit powder in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain a microcrystalline glass blank; and (3) placing the microcrystalline glass blank in a tunnel kiln for sectional heating treatment, then cooling along with the kiln, taking out to obtain a crude product of the microcrystalline glass, and polishing and trimming the crude product to obtain the magnetic microcrystalline glass. The method has the advantages of simple process flow, low production cost and high comprehensive utilization rate of the asbestos tailings. Specifically, the method may comprise the steps of:
1) after the asbestos tailings and the ingredients are pretreated, weighing, matching and uniformly mixing to obtain microcrystalline glass biscuit powder;
2) paving the microcrystalline glass biscuit powder obtained in the step 1) in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain a microcrystalline glass biscuit;
3) and (3) placing the microcrystalline glass biscuit obtained in the step 2) in a tunnel kiln for sectional heating treatment, then cooling along with the kiln, taking out, polishing and trimming to obtain a microcrystalline glass product.
The asbestos tailings in the step 1) comprise the following chemical components in percentage by weight: MgO 40-50%, SiO 2 30～50％，Fe2O3 5～20％，CaO 3～10％，Al2O3 0.5～1.2％，Cr2O3 0.2～0.8％，NiO 0.2～0.5％，K2O 0.1～0.3％，MnO 0.1～0.2％,BaO 0.02～0.08％，Co3O40.01-0.05% and 2.46-15.65% of ignition loss; the ingredients areOne or two of industrial caustic soda, potash feldspar, nepheline, perlite, waste glass, borax and polishing and trimming waste; the pretreatment process of the asbestos tailings comprises the following steps: crushing, grinding, grading, roasting at low temperature (the temperature is 600-750 ℃, and the heat preservation time is 30-90 min). The pretreatment process of the ingredients comprises the following steps: crushing, grinding, grading and drying; the asbestos tailings and the ingredients are matched according to the mass percentage, namely 90-100% of asbestos tailings, 0-10% of industrial caustic soda, 0-7% of potassium feldspar, 0-5% of nepheline, 0-10% of perlite, 0-10% of waste glass, 0-5% of borax and 0-2% of polishing and trimming waste. The obtained biscuit powder has the granularity of 10-80 mu m, and the sintering reaction is influenced if the granularity is higher than the limit, so that the compactness of the microcrystalline glass product is reduced; if the particle size of the powder is lower than the limit, deep processing treatment is required, and the energy consumption is high.
The pressure of the dry pressing in the step 2) is 20-100 MPa, and the pressure maintaining time is 10-60 s. The pressure is too high, and the biscuit is easy to crack and difficult to form; the pressure is too low, the bonding effect among particles is poor, and the gaps are more. The long dwell time and small gap affect the cost.
The heat treatment system of the microcrystalline glass biscuit in the step 3) is as follows: and in a tunnel kiln, heating the biscuit to 750-900 ℃ from room temperature at a heating rate of 5-10 ℃/min, preserving heat for 30-60 min, continuing heating to 1100-1250 ℃ at a heating rate of 3-5 ℃/min, preserving heat for 30-90 min, and naturally cooling.
The microcrystalline glass prepared by the method of the two exemplary embodiments has excellent performance, and the performance indexes are as follows: the bulk density is 2.0 to 3.36g/cm3Water absorption rate<0.10-0.02%, breaking strength 68-125 MPa, acid resistance 99.8-99.9%, alkali resistance 99.9-99.99%, and saturation magnetic induction: 0.01-10 emu/g, coercive force: 120 to 1000 Oe. Has strong magnetism and has the functions of absorbing microwaves, electromagnetic waves and the like.
The phases of the prepared glass ceramics can include five types:
the first type:
the mass ratio of the glass phase to the microcrystalline phase can be 15: 85-5: 95. The mass fraction of the microcrystalline phase in the microcrystalline glass can be 85-95%, and the crystalline phase with the content can obviously improve the toughness, compression resistance, fracture resistance and other properties of the microcrystalline glass; the rest 5-15% of the glass phase is interlaced among the microcrystalline phases in the microcrystalline glass structure in a net structure, so that the toughness of the microcrystalline glass can be remarkably improved, and the microcrystalline glass has better glossiness.
The microcrystalline phases may include a forsterite phase, an enstatite phase, a magneferrite phase, and a diopside phase. Wherein, the mass ratio of each phase in the microcrystalline phase can be: forsterite phase: 45-60%, enstatite phase: 30-48%, and the pleonaste phase: 4-18%, diopside phase: 3-15%. In the microcrystalline phase, the forsterite phase has the highest content, and the content can ensure that the microcrystalline glass has the advantages of high temperature resistance, erosion resistance, good chemical stability and the like; the enstatite phase with the content can fill the crystal boundary pores of the forsterite phase and the pleonaste phase to form a dense accumulation body, so that the compactness of the glass ceramics can be improved; the content of the pleonaste phase can enable the microcrystalline glass to have obvious soft magnetism; the thermal stability of the diopside content is poor at a high temperature, and a solid solution is formed by partial crystalline phase, forsterite and enstatite, so that the structural pores of the microcrystalline glass are effectively reduced.
The forsterite phase may have a short stripe shape, a length of 850 to 2000nm, and a width of 500 to 1200 nm. The morphology of the enstatite phase may include spherical particles, and the particle size may be 300 to 1250 nm. The form of the pleonaste phase can include a round rod shape, the length can be 1500-3800 nm, and the width can be 850-1800 nm. The diopside phase may be in the form of long columns with a length of 1350-3400 nm and a width of 600-1850 nm.
The higher the content of the serpentine in the raw materials is, the higher the content of the forsterite phase and the enstatite phase in the microcrystalline glass is; the higher the content of brucite in the raw materials is, the higher the content of forsterite phase in the microcrystalline glass is; the higher the content of magnetite in the raw material is, the higher the content of the ferrierite spinel in the glass-ceramic is, the higher the content of dolomite in the raw material is, and the higher the content of the diopside phase in the glass-ceramic is.
In the microcrystalline glass having the microcrystalline phase, the volume ratio of the pores may be 3 to 5%. The stomata comprise open stomata and closed stomata. Wherein 75-90% of the gas-developing holes are positioned in the microcrystalline glass, and 60-85% of the gas-closing holes are positioned on the surface of the microcrystalline glass. The pore diameter of the open pores can be 350-2400 nm, and the pore diameter of the closed pores can be 120-1850 nm.
The second type:
the microcrystalline phase content of the microcrystalline glass can be 68-85%, and the crystalline phase with the content can improve the toughness, the compression resistance, the fracture resistance and other properties of the microcrystalline glass; the rest 15-32% of the glass phase is tightly combined with the microcrystalline phase in the microcrystalline glass structure in a band-shaped structure, so that the toughness of the microcrystalline glass can be obviously improved, meanwhile, the glossiness of the microcrystalline glass can be obviously improved due to the high content of the glass phase, and the size and porosity of pores can be effectively reduced.
The microcrystalline phases may include a forsterite phase, an enstatite phase, a magneferrite phase, and a diopside phase.
Wherein, the forsterite phase and the enstatite phase are main crystal phases, and the pleonaste phase and the diopside phase are auxiliary crystal phases. In the microcrystalline phase, the mass fraction of the forsterite phase can be 32-55%, the mass fraction of the enstatite phase can be 20-48%, the mass fraction of the hercynite phase can be 15-28%, and the mass fraction of the diopside phase can be 5-20%. The content of the forsterite phase in the range can improve the performances of high temperature resistance, erosion resistance, chemical stability and the like of the microcrystalline glass; the crystal contained in the enstatite phase with the content can fill the crystal boundary pores of a forsterite crystal phase and a pleonaste crystal phase to form a dense accumulation body, so that the compactness of the microcrystalline glass can be improved; the magnesium ferrite spinel phase with the content can enable the microcrystalline glass to have obvious soft magnetism; the diopside phase with the content has poor thermal stability at a higher temperature, and a solid solution is formed by partial crystalline phase, the forsterite phase and the enstatite phase, so that the structural pores of the microcrystalline glass are effectively reduced.
Wherein, the form of the forsterite phase can comprise a short strip shape, the length can be 650nm to 2000nm, and the width can be 480 nm to 1200 nm. The morphology of the enstatite phase may include spherical particles, and the particle size may be 250 to 1250 nm. The form of the pleonaste phase can be a round rod, the length can be 1500-3600 nm, and the width can be 800-1800 nm. The diopside phase may be in the form of long columns with a length of 1250-3200 nm and a width of 600-1850 nm.
The microcrystalline glass with the crystal phase can comprise the following components in percentage by mass:
30～45％MgO、28～45％SiO2、6～15％Fe2O3、3～10％CaO、0.8～1.2％Al2O3、0.2～0.8％Cr2O3、0.2～0.5％NiO、0.2～0.3％K2O、0.1～0.3％MnO。
in the microcrystalline glass having the microcrystalline phase, the volume ratio of the pores can be 1.5-3%. The stomata comprise open stomata and closed stomata. Wherein 72-88% of the gas-emitting holes are positioned in the microcrystalline glass, and 68-92% of the gas-closing holes are positioned on the surface of the microcrystalline glass. The pore diameter of the air-revealing pores can be 350-2400 nm, and the pore diameter of the air-blocking pores can be 280-2400 nm.
In the third category:
the mass fraction of the microcrystalline phase in the microcrystalline glass can be 80-92%, and the crystalline phase with the content can obviously improve the toughness, compression resistance, fracture resistance and other properties of the microcrystalline glass; the rest 8-20% of the glass phase is interlaced among the microcrystalline phases in the microcrystalline glass structure in a net structure, so that the toughness of the microcrystalline glass can be remarkably improved, and the microcrystalline glass has better glossiness.
The microcrystalline phases may include a forsterite phase, a akermanite phase, a hercynite phase, and a diopside phase. Wherein, the forsterite phase and the akermanite phase are main crystal phases, and the pleonaste phase and the pyroxene phase are auxiliary crystal phases. In the microcrystalline phase, the mass fraction of the forsterite phase can be 35-58%, the mass fraction of the akermanite phase can be 20-45%, the mass fraction of the hercynite phase can be 12-28%, and the mass fraction of the diopside phase can be 8-20%. The forsterite phase has the highest content, and can improve the performances of high temperature resistance, erosion resistance, chemical stability and the like of the microcrystalline glass; the akermanite phase in the proportion can improve the chemical stability and the thermal stability of the glass ceramics; the content of the magnesium ferrite spinel phase in the proportion ensures that the microcrystalline glass has obvious soft magnetism; the diopside phase has poor thermal stability at a higher temperature, and partial crystal phase and forsterite form a solid solution, so that the porosity of the microcrystalline glass structure can be effectively reduced.
Wherein the forsterite phase may have a short strip shape, a length of 850-2000 nm, and a width of 500-1250 nm. The form of the akermanite phase can include a square grain shape, and the size can be 250-1200 nm. The form of the pleonaste phase can include a round rod shape, the length can be 1500-3800 nm, and the width can be 850-1800 nm. The diopside phase may be in the form of long columns with a length of 1350-3400 nm and a width of 600-1850 nm.
The microcrystalline glass with the crystal phase can comprise the following components in percentage by mass:
35～48％MgO、25～40％SiO2、8～20％Fe2O3、15～30％CaO、0.8～1.2％Al2O3、0.2～0.8％Cr2O3、0.2～0.5％％NiO、0.2～0.3％K2O、0.1～0.3％MnO。
in the microcrystalline glass having the microcrystalline phase, the proportion of pores can be 1.8-4%. The stomata comprise open stomata and closed stomata. Wherein 85-92% of the gas-emitting holes are positioned in the microcrystalline glass, and 65-85% of the gas-closing holes are positioned on the surface of the microcrystalline glass. The pore diameter of the open pores can be 280-1850 nm, and the pore diameter of the closed pores can be 150-1350 nm.
The fourth type:
in the microcrystalline glass, the content of microcrystalline phase can reach 78-90%, and the crystalline phase with the content can obviously improve the compression resistance, the folding resistance and other properties of the microcrystalline glass; the rest 10-22% of the glass phase is tightly combined with the microcrystalline phase in the microcrystalline glass structure in a strip-shaped structure, so that the toughness of the microcrystalline glass can be improved.
The microcrystalline phases may include a forsterite phase, a diopside phase, and a hercynite phase. Main crystal phase: forsterite and diopside phases, secondary crystalline phase: a magnesium ferrite phase.
In the microcrystalline phase, the mass ratio of the forsterite phase can be 36-50%, which can improve the performances of high temperature resistance, erosion resistance, chemical stability and the like of the microcrystalline glass; the mass ratio of the diopside phase can be 25-38%, the thermal stability is poor at a high temperature, and a solid solution is formed by partial diopside phase and the forsterite phase, so that the structural pores of the microcrystalline glass are effectively reduced; the content of the magnesium-iron spinel phase can be 18-28% by mass, and the content of the magnesium-iron spinel phase enables the microcrystalline glass to have obvious soft magnetism.
Wherein, the form of the forsterite phase can comprise a short strip shape, the length can be 850-2000 nm, and the width can be 450-1180 nm; the diopside phase may be in the form of slab, and may have a length of 1200-3400 nm and a width of 800-2000 nm. The form of the pleonaste phase can be a round rod, the length can be 1500-3600 nm, and the width can be 850-1800 nm.
The microcrystalline glass with the crystal phase can comprise the following components in percentage by mass: 35 to 50% SiO2、28～38％MgO、12～25％Fe2O3、3～8％CaO、0.8～2％Al2O3、0.2～0.8％Cr2O3、0.2～0.5％NiO、0.1～0.4％K2O、0.1～0.3％MnO。
In the microcrystalline glass having the microcrystalline phase, the proportion of pores can be 1.8-3.5%. The stomata comprise open stomata and closed stomata. Wherein 68-82% of the gas-developing holes are positioned in the microcrystalline glass, and 60-85% of the gas-closing holes are positioned on the surface of the microcrystalline glass. The pore diameter of the gas-open pore can be 420-2500 nm, and the pore diameter of the gas-close pore can be 280-2250 nm.
In the microcrystalline glass containing the four phases, most of the apparent pores are in the microcrystalline glass structure, and few apparent pores exist on the surface, so that the microcrystalline glass does not absorb water basically due to the distribution of the pores, and meanwhile, the internal apparent pores can be beneficial to reducing the density of the microcrystalline glass body and preparing the light microcrystalline glass.
The fifth type:
the mass fraction of the microcrystalline phase in the microcrystalline glass can be 88-95%, and the crystalline phase with the content can obviously improve the compression resistance, the folding resistance and other properties of the microcrystalline glass; the rest 5-12% of the glass phase is tightly combined with the microcrystalline phase in the microcrystalline glass structure in a net structure, so that the toughness of the microcrystalline glass can be improved.
The microcrystalline phase of the glass-ceramic may include a forsterite phase, a hercynite phase, and an enstatite phase. Wherein the forsterite phase and the forsterite phase are main crystal phases, and the pleonaste phase and the enstatite phase are auxiliary crystal phases. In the microcrystalline phase, the mass fraction of the forsterite phase can be 30-48%, the mass fraction of the forsterite phase can be 25-40%, the mass fraction of the hercynite phase can be 8-20%, and the mass fraction of the enstatite phase can be 15-36%. The forsterite phase and the calcium forsterite phase in the proportion can improve the performances of high temperature resistance, erosion resistance, chemical stability and the like of the microcrystalline glass; the content of the magnesium ferrite spinel phase in the proportion ensures that the microcrystalline glass has obvious soft magnetism; the crystal contained in the enstatite phase with the content can be filled in a forsterite crystal phase, a calcium forsterite crystal phase and a pleonaste crystal phase crystal boundary pore to form a level-density accumulation body, and the compactness of the microcrystalline glass can be improved.
Wherein, the form of the forsterite phase can comprise a short strip shape, the length can be 800nm to 1850nm, and the width can be 500nm to 1200 nm; the morphology of the calcium-magnesium olivine phase can comprise a short column shape, the length can be 950 nm-2000 nm, and the width can be 550 nm-1650 nm; the magnesium-iron spinel phase can be in a shape of a round rod, the length of the magnesium-iron spinel phase can be 1500 nm-3600 nm, and the width of the magnesium-iron spinel phase can be 850 nm-1800 nm. The morphology of the enstatite phase may comprise spherical particles, which may range in size from 250nm to 1500 nm.
The microcrystalline glass with the crystal phase can comprise the following components in percentage by mass: 32-45% MgO, 28-40% SiO2、12～20％CaO、3～10％Fe2O3、0.8～2％Al2O3、0.2～0.8％Cr2O3、0.2～0.5％NiO、0.1～0.3％K2O、0.1～0.3％MnO。
In the microcrystalline glass having the above microcrystalline phase, the proportion of pores may be 4 to 6%. The stomata comprise open stomata and closed stomata. Wherein 20-45% of the gas-developing holes are positioned in the microcrystalline glass, and 30-50% of the gas-closing holes are positioned on the surface of the microcrystalline glass. The pore diameter of the air-revealing hole can be 480-2500 nm, and the pore diameter of the air-closing hole can be 300-2200 nm. Most of the air holes are arranged on the surface of the microcrystalline glass structure, and few air holes are arranged inside the microcrystalline glass structure, so that the microcrystalline glass has partial sound absorption and noise reduction performance due to the distribution of the air holes; and the ability to absorb a portion of the dust gas to purify the air.
In order that the above-described exemplary embodiments of the invention may be better understood, further description thereof with reference to specific examples is provided below.
Example 1
1) After the asbestos tailings and the ingredients are pretreated, weighing, matching and uniformly mixing to obtain the microcrystalline glass biscuit powder. The asbestos tailings comprise the following chemical components in percentage by weight: MgO 40%, SiO2 35％，Fe2O3 10％，CaO 6％，Al2O3 1％，Cr2O3 0.5％，NiO 0.3％，K2O 0.2％，MnO 0.1％,BaO 0.05％，Co3O40.03 percent and ignition loss of 6.82 percent; auxiliary materials: waste glass and feldspar (namely potassium feldspar or albite) respectively account for 5 percent and 3 percent of the asbestos tailings by mass; pretreatment: the asbestos tailings are pre-roasted for 1 hour at 700 ℃ for dehydration, and then are uniformly mixed with auxiliary materials and ball-milled to 50um to obtain biscuit powder.
2) Spreading the microcrystalline glass biscuit powder obtained in the step 1) in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain the microcrystalline glass biscuit. Wherein the pressure of the dry pressing molding is 30MPa, and the dwell time is 60 s.
3) And (3) placing the microcrystalline glass biscuit obtained in the step 2) in a tunnel kiln for sectional heating treatment, then cooling to about 200 ℃ along with the kiln, taking out, polishing and trimming the microcrystalline glass biscuit to obtain a microcrystalline glass product. And the waste materials generated by polishing and trimming are recycled as ingredients. And (3) biscuit sectional heat treatment: heating to 850 ℃ at room temperature, heating at the speed of 10 ℃/min, and keeping the temperature for 1 h; heating to the temperature of 850 ℃ to 1200 ℃, heating at the speed of 5 ℃/min, and keeping the temperature for 1 h.
The X-ray diffraction analysis results of the product obtained in this example are shown in fig. 3, which shows the formation of a forsterite phase, an enstatite phase, a magnesio-hercynite phase and a diopside phase in the product obtained. The scanning electron micrograph of the product obtained in the example is shown in figure 4, wherein the average grain diameter of the crystal grains is about 500nm, and the combination among the crystal grains is denser and the distribution is more uniform. The hysteresis loop diagram of the product obtained in the example is shown in FIG. 5, the saturation magnetic induction of the obtained glass ceramics is 1.652emu/g, the coercive force is 185.256Oe, and the glass ceramics show obvious soft magnetism. The product has the following physical and chemical properties: density 3.16g/cm3192MPa of compressive strength, 88MPa of bending strength, 0.026 of water absorption, 99.88% of acid resistance and high resistanceAnd the alkalinity is 99.985 percent.
Example 2
1) After the asbestos tailings and the ingredients are pretreated, weighing, matching and uniformly mixing to obtain microcrystalline glass biscuit powder; the asbestos tailings comprise the following chemical components in percentage by weight: MgO 38%, SiO2 35％，Fe2O3 8％，CaO 15％，Al2O3 1％，Cr2O3 0.5％，NiO 0.3％，K2O 0.2％，MnO 0.1％，BaO 0.05％，Co3O40.02 percent and ignition loss of 1.83 percent; auxiliary materials: caustic soda and potash feldspar respectively account for 5 percent and 3 percent of the mass fraction of the asbestos tailings. Pretreatment: the asbestos tailings are pre-roasted for 1 hour at 750 ℃ for dehydration, and then are uniformly mixed with auxiliary materials and ball-milled to 50um to obtain biscuit powder.
2) Spreading the microcrystalline glass biscuit powder obtained in the step 1) in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain the microcrystalline glass biscuit. Wherein the pressure of the dry pressing molding is 50MPa, and the dwell time is 60 s.
3) And (3) placing the microcrystalline glass biscuit obtained in the step 2) in a tunnel kiln for sectional heating treatment, then cooling to about 200 ℃ along with the kiln, taking out, polishing and trimming the microcrystalline glass biscuit to obtain a microcrystalline glass product. And the waste materials generated by polishing and trimming are recycled as ingredients. Wherein, the biscuit segmentation heat treatment: heating to 800 ℃ at room temperature, heating at the speed of 5 ℃/min, and keeping the temperature for 1 h; heating to 1250 ℃ at 800 ℃, heating up at the speed of 3 ℃/min and keeping the temperature for 1 h.
The X-ray diffraction analysis of the product obtained in this example is shown in fig. 6, which indicates that a forsterite phase, akermanite phase, hercynite phase and diopside phase are formed in the product. The scanning electron micrograph of the product obtained in this example is shown in fig. 7, and the average grain size of the crystal grains is about 450nm, and the bonding between the crystal grains is dense and the distribution is uniform. The hysteresis loop of the product obtained in this example is shown in fig. 8, and the microcrystalline glass has a saturation magnetic induction of 2.556emu/g and a coercive force of 235.628Oe, and exhibits remarkable soft magnetism. The product has the following physical and chemical properties: density 3.28g/cm3235MPa compressive strength, 92MPa bending strength, 0.028% water absorption, 99.82% acid resistance and 99.976% alkali resistance。
Example 3
1) After the asbestos tailings and the ingredients are pretreated, weighing, matching and uniformly mixing to obtain the microcrystalline glass biscuit powder. The asbestos tailings comprise the following chemical components in percentage by weight: MgO 40%, SiO2 38％，Fe2O3 8％，CaO 6％，Al2O3 1％，Cr2O30.5％，NiO0.3％，K2O 0.2％，MnO 0.1％，BaO 0.05％，Co3O40.03 percent and 5.82 percent loss on ignition; auxiliary materials: caustic soda and potassium feldspar respectively account for 5 percent and 3 percent of the mass fraction of the asbestos tailings; pretreatment: the asbestos tailings are pre-roasted for 1 hour at 750 ℃ for dehydration, and then are uniformly mixed with auxiliary materials and ball-milled to 50um to obtain biscuit powder.
2) Spreading the microcrystalline glass biscuit powder obtained in the step 1) in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain the microcrystalline glass biscuit. The pressure of dry pressing is 80MPa, and the pressure maintaining time is 60 s.
3) And (3) placing the microcrystalline glass biscuit obtained in the step 2) in a tunnel kiln for sectional heating treatment, then cooling to about 200 ℃ along with the kiln, taking out, polishing and trimming the microcrystalline glass biscuit to obtain a microcrystalline glass product. And the waste materials generated by polishing and trimming are recycled as ingredients. And (3) biscuit sectional heat treatment: raising the temperature to 800 ℃ at the temperature raising speed of 10 ℃/min, and keeping the temperature for 0.5 h; raising the temperature to 1250 ℃ at the temperature of 800 ℃, wherein the temperature raising speed is 5 ℃/min, and keeping the temperature for 1 h.
The X-ray diffraction analysis results of the product obtained in this example are shown in fig. 9, indicating that a forsterite phase, an enstatite phase, a magnesiospinel phase and a diopside phase are formed in the product obtained. The scanning electron micrograph of the product obtained in this example is shown in fig. 10, and the average grain size of the crystal grains is about 450nm, and the bonding between the crystal grains is dense and the distribution is uniform. The hysteresis loop diagram of the product obtained in this example is shown in fig. 11, and the microcrystalline glass has a saturation magnetic induction of 2.036emu/g and a coercive force of 208.625Oe, and exhibits remarkable soft magnetism. The product has the following physical and chemical properties: density 3.25g/cm3The compressive strength is 220Mpa, the bending strength is 85Mpa, the water absorption is 0.035%, the acid resistance is 99.85%, and the alkali resistance is 99.979%.
Example 4
1) After the asbestos tailings and the ingredients are pretreated, weighing, matching and uniformly mixing to obtain the microcrystalline glass biscuit powder. The asbestos tailings comprise the following chemical components in percentage by weight: MgO 38%, SiO2 34％，Fe2O3 6％，CaO 15％，Al2O3 1.5％，Cr2O3 0.5％，NiO 0.3％，K2O 0.2％，MnO 0.1％,BaO 0.06％，Co3O40.03 percent and 4.31 percent of ignition loss; auxiliary materials: waste glass and potassium feldspar respectively account for 5 percent and 3 percent of the mass fraction of the asbestos tailings; pretreatment: the asbestos tailings are pre-roasted at 750 ℃ for 0.5h for dehydration, and then are uniformly mixed with auxiliary materials and ball-milled to 50um to obtain biscuit powder.
2) Spreading the microcrystalline glass biscuit powder obtained in the step 1) in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain the microcrystalline glass biscuit. The pressure of dry pressing is 80MPa, and the pressure maintaining time is 60 s.
3) And (3) placing the microcrystalline glass biscuit obtained in the step 2) in a tunnel kiln for sectional heating treatment, then cooling to about 200 ℃ along with the kiln, taking out, polishing and trimming the microcrystalline glass biscuit to obtain a microcrystalline glass product. And the waste materials generated by polishing and trimming are recycled as ingredients. And (3) biscuit sectional heat treatment: heating to 850 ℃ at room temperature, heating at the speed of 10 ℃/min, and keeping the temperature for 1 h; heating to 250 ℃ at 850 ℃, heating at the speed of 5 ℃/min, and keeping the temperature for 1 h.
The X-ray diffraction analysis results of the product obtained in this example are shown in fig. 12, which indicates that a forsterite phase, a hercynite phase and an enstatite phase are formed in the product obtained. The scanning electron micrograph of the product obtained in this example is shown in fig. 13, and the average grain size of the crystal grains is about 550nm, and the bonding between the crystal grains is dense and the distribution is uniform. The hysteresis chart of the product obtained in this example is shown in FIG. 14，The microcrystalline glass has a saturation magnetic induction of 1.286emu/g and a coercive force of 125.362Oe, and shows remarkable soft magnetism. The product has the following physical and chemical properties: density 2.862g/cm3182Mpa in compressive strength, 78Mpa in bending strength, 0.018% in water absorption, 99.81% in acid resistance and 99.973% in alkali resistance.
Example 5
1) After the asbestos tailings and the ingredients are pretreated, weighing, matching and uniformly mixing to obtain the microcrystalline glass biscuit powder. The asbestos tailings comprise the following chemical components in percentage by weight: MgO 32%, SiO 2 40％，Fe2O3 16％，CaO 5％，Al2O3 1％，Cr2O3 0.5％，NiO 0.3％，K2O 0.3％，MnO 0.2％,BaO 0.05％，Co3O40.03 percent and 4.62 percent of ignition loss; auxiliary materials: waste glass and perlite respectively account for 5 percent and 3 percent of the mass fraction of the asbestos tailings; pretreatment: the asbestos tailings are pre-roasted at 700 ℃ for 1.5h for dehydration, and then are uniformly mixed with auxiliary materials and ball-milled to 20um to obtain biscuit powder.
2) Spreading the microcrystalline glass biscuit powder obtained in the step 1) in a forming grinding tool, and performing dry pressing forming by using a blank forming press to obtain the microcrystalline glass biscuit. The pressure of dry pressing is 100MPa, and the pressure maintaining time is 60 s.
3) And (3) placing the microcrystalline glass biscuit obtained in the step 2) in a tunnel kiln for sectional heating treatment, then cooling to about 200 ℃ along with the kiln, taking out, polishing and trimming the microcrystalline glass biscuit to obtain a microcrystalline glass product. And the waste materials generated by polishing and trimming are recycled as ingredients. And (3) biscuit sectional heat treatment: heating to 850 ℃ at room temperature, heating at the speed of 10 ℃/min, and keeping the temperature for 1 h; heating to the temperature of 850 ℃ to 1200 ℃, heating at the speed of 5 ℃/min, and keeping the temperature for 1.5 h.
The X-ray diffraction analysis of the product obtained in this example is shown in fig. 15, which indicates that a forsterite phase, a hercynite phase and a diopside phase are formed in the product. The scanning electron micrograph of the product obtained in this example is shown in fig. 16, and the average grain size of the crystal grains is about 500nm, and the bonding between the crystal grains is dense and the distribution is uniform. As shown in fig. 17, the hysteresis chart of the product obtained in this example shows that the microcrystalline glass has a saturation magnetic induction of 7.816emu/g and a coercive force of 482.258Oe, and exhibits a remarkable soft magnetism. The product has the following physical and chemical properties: density 3.352g/cm3208Mpa in compression strength, 116Mpa in bending strength, 7.5 mohs hardness, 0.012% in water absorption, 99.898% in acid resistance and 99.982% in alkali resistance.
In conclusion, compared with the prior art, the process for preparing the functional glass ceramics by directly sintering the asbestos tailings has the following beneficial effects:
1) the technological process adopted by the invention comprises the steps of burdening → blank making → crystallization sintering heat treatment → polishing and trimming → products, the technological process and the links are simplified, only one high-temperature heat treatment is needed, the complex processes of high-temperature melting, water quenching and the like are avoided, and the production energy consumption is reduced.
2) The utilization rate of the asbestos tailings is high, the utilization rate of the asbestos tailings reaches 90-100%, the ingredients are 0-10% of the mass percentage of the asbestos tailings, and polishing and trimming waste materials are recycled.
3) The microcrystalline glass product prepared by the method has a density of 2.0-3.36 g/cm2The water absorption rate is 0.01-0.035%, the breaking strength is 68-125 MPa, the acid resistance is 99.8-99.9%, and the alkali resistance is 99.9-99.99%. All indexes are comparable to marble, granite and ceramic tile, and can be used as high-grade building decorative material, artistic carving and functional ceramic material
4) Based on the characteristic of rich iron in the asbestos tailing raw material, the controllable crystallization of a magnetic crystalline phase in the preparation process of the microcrystalline glass is realized by controlling a heat treatment system, and the magnetic microcrystalline glass with outstanding soft magnetic performance and good use performance is obtained (saturation magnetic induction: 0.01-10 emu/g, coercive force: 120-1000 Oe), is expected to be applied to the fields of biology, electronic engineering and the like; provides a new way and method for the high value-added utilization of asbestos tailings or the production of functionalized magnetic glass ceramics.
5) The process carries out harmless phase inversion on the asbestos tailings, has no harmful gas emission in the heat treatment process, has no three-waste emission in the production process, and meets the technical requirements of green manufacturing processes.
6) In the preparation process, no binder or granulating agent is needed to be added, or only a small amount of binder is needed to be added, so the process is simplified and the cost is low.
Although the present invention has been described above in connection with exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes may be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (8)
1. A method for preparing functional glass ceramics by directly sintering asbestos tailings is characterized by comprising the following steps:
crushing and drying asbestos tailings to obtain biscuit powder, wherein the water content of the biscuit powder is 1.2-3.5% by mass;
pressing and molding the biscuit powder to obtain a blank;
heating the blank to 750-900 ℃ and preserving heat to promote nucleation and crystallization of the blank, then heating to 1100-1250 ℃ for sintering, and cooling after sintering is finished to obtain microcrystalline glass;
heating the blank to 750-900 ℃ at a heating rate of 5-10 ℃/min;
heating to 1100-1250 ℃ at a heating rate of 3-5 ℃/min;
the drying comprises low-temperature roasting dehydration, wherein the low-temperature roasting dehydration is to preserve the heat of the asbestos tailings at 600-750 ℃ so that the serpentine in the asbestos tailings is subjected to dehydration reaction to form forsterite.
2. A method for preparing functional glass ceramics by directly sintering asbestos tailings is characterized by comprising the following steps:
pretreating raw materials to obtain biscuit powder, wherein the raw materials comprise asbestos tailings and ingredients, the mass ratio of the asbestos tailings in the raw materials is more than 90%, the ingredients comprise fluxing agent and/or microcrystalline glass component replenisher, and the water content of the biscuit powder is 1.2-3.5% by mass percent;
pressing and molding the biscuit powder to obtain a blank;
heating the blank to 750-900 ℃ and preserving heat to promote nucleation and crystallization of the blank, then heating to 1100-1250 ℃ for sintering, and cooling after sintering is finished to obtain microcrystalline glass;
heating the blank to 750-900 ℃ at a heating rate of 5-10 ℃/min;
heating to 1100-1250 ℃ at a heating rate of 3-5 ℃/min;
the pretreatment comprises drying, crushing and mixing; the drying of the asbestos tailings comprises low-temperature roasting dehydration, wherein the low-temperature roasting dehydration is to keep the temperature of the asbestos tailings at 600-750 ℃ so that the serpentine in the asbestos tailings is subjected to dehydration reaction to form forsterite.
3. The method for preparing functional glass ceramics by directly sintering asbestos tailings according to claim 2, wherein the ingredients comprise: at least one of industrial caustic soda, potash feldspar, nepheline, perlite, waste glass, borax, polishing and trimming waste.
4. The method for preparing functional glass-ceramics by directly sintering asbestos tailings as claimed in claim 1 or 2, wherein the asbestos tailings comprise chrysotile asbestos tailings.
5. The method for preparing functional glass ceramics by directly sintering asbestos tailings according to claim 1 or 2, wherein the particle size of the biscuit powder is below 80 μm.
6. The method for preparing functional glass ceramics by directly sintering asbestos tailings according to claim 1 or 2, wherein the step of press forming comprises:
uniformly and flatly paving the biscuit powder in a mould, maintaining the pressure for 10-60 s under the pressure of 20-100 MPa, and then demoulding to obtain a blank.
7. The method for preparing functional glass ceramics by directly sintering asbestos tailings according to claim 1 or 2, wherein the heat preservation time after heating to 750-900 ℃ is 30-60 min; and after heating to 1100-1250 ℃, preserving heat for 30-90 min.
8. The method for preparing functional glass ceramics by directly sintering asbestos tailings according to claim 1 or 2, wherein the method further comprises the steps of:
and (3) trimming and/or polishing the obtained microcrystalline glass, and returning waste materials generated by trimming and/or polishing to be used for manufacturing the biscuit powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811318321.0A CN109052970B (en) | 2018-11-07 | 2018-11-07 | Method for preparing functional glass ceramics by directly sintering asbestos tailings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811318321.0A CN109052970B (en) | 2018-11-07 | 2018-11-07 | Method for preparing functional glass ceramics by directly sintering asbestos tailings |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109052970A CN109052970A (en) | 2018-12-21 |
| CN109052970B true CN109052970B (en) | 2022-03-18 |
Family
ID=64789278
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811318321.0A Active CN109052970B (en) | 2018-11-07 | 2018-11-07 | Method for preparing functional glass ceramics by directly sintering asbestos tailings |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109052970B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110818442B (en) * | 2019-11-28 | 2022-03-18 | 西南科技大学 | CaO-MgO-SiO using asbestos tailings as raw material2Is a foamed ceramic |
| CN110713377B (en) * | 2019-11-28 | 2022-04-08 | 西南科技大学 | Preparation of CaO-MgO-SiO by using asbestos tailings2Method for making foamed ceramics |
| CN112919782B (en) * | 2021-03-03 | 2023-11-14 | 盐城明洋石英制品有限公司 | Be used for quartz glass automatic sintering device |
| CN115321950B (en) * | 2022-09-01 | 2023-06-20 | 西南科技大学 | Ferromagnetic microcrystalline ceramic and preparation method thereof |
| CN116986821B (en) * | 2023-06-26 | 2024-05-28 | 西南科技大学 | Foam microcrystalline glass and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101891389A (en) * | 2010-07-22 | 2010-11-24 | 西南科技大学 | Chrysotile tailing microcrystal glass and preparation method thereof |
-
2018
- 2018-11-07 CN CN201811318321.0A patent/CN109052970B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101891389A (en) * | 2010-07-22 | 2010-11-24 | 西南科技大学 | Chrysotile tailing microcrystal glass and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109052970A (en) | 2018-12-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109052970B (en) | Method for preparing functional glass ceramics by directly sintering asbestos tailings | |
| CN109320219B (en) | High-performance aluminum-chromium refractory material and manufacturing method and application thereof | |
| US9290409B2 (en) | Glaze composition, method for manufacturing the glaze composition and methods of glazing | |
| CN110713377B (en) | Preparation of CaO-MgO-SiO by using asbestos tailings2Method for making foamed ceramics | |
| CN104045354B (en) | Regeneration corundum spinelle does not burn refractory brick | |
| CN102795870B (en) | Light-weight magnesia brick and preparation method thereof | |
| CN107266052B (en) | Alumina-titanium calcium aluminate-silicon carbide complex phase refractory material and preparation method thereof | |
| CN107954732B (en) | Cordierite-forsterite sagger, preparation method and application thereof | |
| CN110818442B (en) | CaO-MgO-SiO using asbestos tailings as raw material2Is a foamed ceramic | |
| CN102101754A (en) | Method for preparing boron-containing foam glass | |
| CN103351162A (en) | Preparation method for aluminum titanate ceramic | |
| CN109133855A (en) | Low temperature light ceramics and its preparation process | |
| CN109320089B (en) | Functional microcrystalline glass using asbestos tailings as raw material | |
| CN110540414A (en) | Preparation method of nano microporous corundum | |
| CN101913843B (en) | Preparation method of emerald ceramic | |
| CN110461789B (en) | Microcrystalline glass and preparation method thereof, composite grinding wheel bonding agent containing microcrystalline glass and preparation method and application of composite grinding wheel bonding agent | |
| KR101696716B1 (en) | Manufacturing method of high-strength artificial stone block using tailing | |
| CN109160741B (en) | Method for preparing microcrystalline glass by directly sintering fly ash | |
| KR101323109B1 (en) | Porous lightweight ceramics and manufacturing method of the same | |
| CN103553560B (en) | A kind of olive stone ore prepares the method for forsterite | |
| CN101672080B (en) | Method for preparing high stone powder mixing quantity baked brick | |
| CN115043591A (en) | Porous microcrystalline ceramic and preparation method thereof | |
| CN115259834A (en) | Preparation method of building ceramic using high-calcium iron tailings as main raw material and ceramic product thereof | |
| CN109160742B (en) | Microcrystalline glass using fly ash as raw material | |
| CN111423223A (en) | Method for preparing ceramic by replacing kaolin with spodumene slag |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |