Glass ceramic precursor, preparation method and application of glass ceramic precursor in preparation of glass ceramic

Abstract

The invention provides a glass ceramic precursor, a preparation method and an application of the glass ceramic precursor in preparation of glass ceramic, the characteristic of high silicon in lead-zinc smelting depleted slag is utilized, household garbage incineration fly ash which is a dangerous waste is added, and the glass ceramic precursor can be prepared after melting-water quenching treatment; on one hand, the smelting depletion slag and the household garbage incineration fly ash can be digested, on the other hand, trace metals in the smelting depletion slag and the household garbage incineration fly ash are immobilized, the strength of the glass ceramic prepared from the glass ceramic precursor is improved, and therefore the utilization efficiency and the additional value of the smelting depletion slag and the household garbage incineration fly ash are effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical fields of non-ferrous smelting and solid waste treatment, in particular to a glass-ceramic precursor, a preparation method thereof and application of the glass-ceramic precursor in preparation of glass-ceramics. BACKGROUND

[0002] Lead-zinc smelting is a process of processing lead and zinc ore concentrate into pure metal. Since lead and zinc often coexist, smelting plants usually process both kinds of concentrates at the same time. Among them, lead smelting widely applies high-efficiency and environmentally-friendly direct smelting technology, which produces crude lead in one or two steps, and then is refined and purified; zinc smelting mainly uses wet process, which obtains high-purity zinc through roasting, acid leaching, solution purification and electrolytic deposition. The whole process highly focuses on sulfur recovery (acid production), heavy metal pollution control and comprehensive recovery of associated valuable metals (such as gold and silver), and is a technology-intensive and environmentally-friendly industrial field.

[0003] However, lead-zinc smelting slag usually contains a large amount of heavy metals, which belongs to typical hazardous waste. In this case, storage has the risk of heavy metal dissolution on the one hand, and shortage of land area on the other hand, so it is urgent to propose an economic utilization method for the part of smelting slag. SUMMARY

[0004] To solve the above problems, the present application provides a glass-ceramic precursor, a preparation method thereof and application of the glass-ceramic precursor in preparation of glass-ceramics. By utilizing the high-silicon characteristics of lead-zinc smelting lean slag, adding household waste incineration fly ash which is also a hazardous waste, and then preparing a glass-ceramic precursor through melting-water quenching treatment, on the one hand, the smelting lean slag and the household waste incineration fly ash are disposed of, on the other hand, the trace metals in the two are immobilized, the strength of the glass-ceramics made of the glass-ceramic precursor is improved, and the utilization efficiency and added value of the smelting lean slag and the household waste incineration fly ash are effectively improved.

[0005] In a first aspect, the present application provides a preparation method of a glass-ceramic precursor, which comprises: mixing the crushed and ground lead-zinc smelting lean slag with household waste incineration fly ash, melting at a temperature of 1400 ℃-1550 ℃, and keeping the temperature for 1 h-2.5 h to form a molten liquid; performing water quenching treatment on the molten liquid at room temperature, drying and crushing the obtained water-quenched slag to obtain the glass-ceramic precursor; wherein the total content of lead and zinc in the lead-zinc smelting lean slag is less than 2 %, the content of iron is less than 10 %, and the content of silicon dioxide is 28 %-55 %.

[0006] Optionally, the mass ratio of the crushed and ground lead-zinc smelting lean slag to the household waste incineration fly ash is (3-8):1.

[0007] Optionally, the lead-zinc smelting lean slag further comprises calcium in an amount less than 10% and magnesium in an amount less than 3%.

[0008] Optionally, the household garbage incineration fly ash at least comprises calcium oxide, magnesium oxide, silicon dioxide, iron oxide, aluminum oxide, zinc, lead, copper, chromium and nickel.

[0009] Optionally, the fineness of the glass-ceramic precursor is 100 μm-500 μm.

[0010] Optionally, the crushing and grinding step comprises: The lead-zinc smelting lean slag is continuously crushed twice in a jaw crusher, and the crushed lead-zinc smelting lean slag is finely ground to form the crushed and ground lead-zinc smelting lean slag.

[0011] Optionally, the particle size of the lead-zinc smelting lean slag after the two crushing processes is less than 2 mm. The fineness of the crushed and ground lead-zinc smelting lean slag is 150 μm-400 μm.

[0012] Optionally, the preparation method of the lead-zinc smelting lean slag comprises: A reducing agent is added to the molten lead-zinc smelting slag, and reduction treatment is performed at a temperature of 1200 ℃-1300 ℃ for 1 h-2 h; after heat preservation and standing, the lower layer is a metal phase, and the upper layer is a lead-zinc smelting lean slag phase; after separation, the lead-zinc smelting lean slag is obtained; The reducing agent is one of coke, coal powder and natural gas. The metal phase is a lead-zinc alloy.

[0013] In a second aspect, the present application provides a glass-ceramic precursor, which is obtained by the preparation method of the first aspect.

[0014] In a third aspect, the present application provides an application of a glass-ceramic precursor in preparing a glass-ceramic, wherein the glass-ceramic precursor is used to prepare a glass-ceramic by nucleation at a transformation temperature. The transformation temperature is 650 ℃-950 ℃. The main crystal phase of the glass-ceramic is wollastonite, the bending strength is 48 MPa-50 MPa, and the compressive strength is 100 MPa-105 MPa.

[0015] In summary, the present application at least has the following beneficial technical effects: 1. This invention provides a method for preparing a microcrystalline glass precursor. The method involves co-melting lead-zinc smelting slag and municipal solid waste incineration fly ash to form a homogeneous glass melt at a high temperature of 1400℃-1550℃, followed by water quenching and rapid solidification. This process stably encapsulates heavy metal ions within a silicate glass network, blocking their migration pathways. This preparation process not only eliminates the environmental risks of lead-zinc smelting slag and municipal solid waste incineration fly ash but also transforms the waste residue into a high-value-added microcrystalline glass precursor. Compared to traditional landfill disposal, this significantly reduces the volume of waste accumulation and produces microcrystalline glass precursor materials that can be directly used in building material production, achieving the dual benefits of pollution control and resource enhancement.

[0016] 2. This invention also provides an application of a microcrystalline glass precursor in the preparation of microcrystalline glass. Nucleation crystallization is performed at a transition temperature, anchoring heavy metals in the microcrystalline glass precursor within the wollastonite crystal structure. Compared to physical encapsulation in the glass phase, the chemical bonding of the crystals forms a more stable containment barrier, ensuring that heavy metals are not released in the natural environment. The microcrystalline glass prepared by this invention, as a building material that can be directly marketed, can replace natural stone in construction projects, helping to alleviate the consumption of natural stone and other building materials. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating the preparation method of the microcrystalline glass precursor proposed in an embodiment of the present invention is shown. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] In the accompanying drawings, the size of constituent elements, the thickness of layers, or areas may sometimes be exaggerated for clarity. Therefore, any implementation of this disclosure is not necessarily limited to the dimensions shown in the drawings, and the shapes and sizes of the components in the drawings do not reflect true proportions. Furthermore, the drawings schematically illustrate ideal examples, and any implementation of this disclosure is not limited to the shapes or values ​​shown in the drawings.

[0021] In the related art, the smelting slag generated by lead-zinc smelting contains residual heavy metals (lead, zinc, etc.), especially a high content of silicon dioxide, which is not efficiently resourceized, resulting in a low overall resource utilization rate. The traditional stockpiling disposal method not only occupies a large amount of land resources, but also has the risk of heavy metal (especially lead and zinc) leaching to pollute the environment.

[0022] On the other hand, municipal solid waste incineration fly ash, as a kind of hazardous waste that needs to be safely disposed of, is rich in heavy metals and chlorides, but the calcium and aluminum components contained therein have the potential to adjust the composition of the melt. The synergistic treatment of these two types of waste is expected to safely accommodate heavy metals while fully utilizing the calcium and aluminum components in the fly ash to optimize the properties of the melt (such as reducing the melting point and improving the flowability), and to explore resourceization pathways for silicon dioxide in the depleted slag (such as preparing building material bases), achieving the goal of efficient resource recovery.

[0023] Based on the problems in the related art, the embodiments of the present application provide an inventive concept: taking advantage of the silicon-based characteristics of lead-zinc smelting depleted slag and combining fly ash to supplement the elements needed for glass formation, the two types of waste are treated by melting-water quenching to convert into high-value-added microcrystalline glass precursors, which can not only accommodate the two types of waste, but also provide a more environmentally friendly and economically efficient method for preparing microcrystalline glass with higher bending strength and higher compressive strength.

[0024] Specifically, referring to Figure 1 The embodiments of the present application provide a preparation method of a microcrystalline glass precursor, which comprises: Step S1: mixing the crushed and ground lead-zinc smelting depleted slag with municipal solid waste incineration fly ash, melting at a temperature of 1400 ℃-1550 ℃, and keeping the temperature for 1 h-2.5 h to form a molten liquid; Step S2: water quenching treatment of the molten liquid at room temperature, and the obtained water-quenched slag is dried and crushed to obtain the microcrystalline glass precursor; Wherein, the total content of lead and zinc in the lead-zinc smelting depleted slag is less than 2 %, the content of iron is less than 10 %, and the content of silicon dioxide is 28 %-55 %.

[0025] In the embodiments of the present application, the lead-zinc smelting depleted slag is the slag after the lead-zinc smelting slag is depleted, and the main components are spinel, amphibole, aluminum iron garnet and other silicate compounds. Compared with the lead-zinc smelting slag, the total content of lead and zinc is greatly reduced to reduce the risk of heavy metal leaching during subsequent melting.

[0026] In the embodiments of the present application, in step S1, the preparation method of the lead-zinc smelting depleted slag comprises: The reducing agent is added into the molten lead-zinc smelting slag, and the reducing treatment is carried out at a temperature of 1200-1300 DEG C for 1-2 hours; after heat preservation and static stratification, the lower layer is a metal phase, and the upper layer is a lead-zinc smelting lean slag phase; after separation, the lead-zinc smelting lean slag is obtained; The reducing agent is one of coke, coal powder and natural gas. The metal phase is a lead-zinc alloy.

[0027] In specific implementation, the lead-zinc smelting slag is derived from the molten slag produced synchronously after the crude lead / zinc is produced by oxidizing smelting of lead-zinc concentrates (such as galena PbS and sphalerite ZnS) in a smelting furnace, and contains not completely separated lead-zinc, iron and gangue components (SiO2, CaO, etc.). The molten lead-zinc smelting slag is directly produced from a smelting furnace in a main lead-zinc metal smelting process, and the temperature of the molten lead-zinc smelting slag directly produced by the smelting furnace is 1200-1350 DEG C, which has already met the temperature for the reducing treatment, so that the reducing treatment can be directly carried out after the reducing agent is added, without additional heating, thereby saving the energy consumption for cooling and remelting. In the embodiment of the application, the reducing treatment is carried out in a reduction furnace, the molten lead-zinc smelting slag produced by the smelting furnace is introduced into the reduction furnace, and the reducing agent is injected into the deep layer of the molten lead-zinc smelting slag by pneumatic injection when the molten lead-zinc smelting slag flows into the reduction furnace, so that instantaneous mixing is realized by using the convection of the melt, and the fluidity of the high-temperature molten lead-zinc smelting slag helps the reducing agent to quickly diffuse, thereby accelerating the reducing treatment. The particle size of the coke and coal powder in the reducing agent is between 0.5 mm and 3 mm. In the static stratification, the temperature gradient in the reduction furnace can be controlled in the heat preservation and static stage, for example, 1300 DEG C in the lower part and 1250 DEG C in the upper part; the high temperature in the lower part can maintain the fluidity of the metal phase, and the temperature reduction in the upper part can promote the increase of the viscosity of the lead-zinc smelting lean slag, thereby accelerating the phase separation.

[0028] The embodiment of the application converts the original lead-zinc smelting slag into the low-toxicity lead-zinc smelting lean slag by reducing smelting, so that the lead and zinc oxides remaining in the slag are reduced to liquid lead-zinc alloy, thereby realizing the deep separation and recovery of heavy metals. After the reducing treatment, the total amount of lead and zinc in the lead-zinc smelting lean slag is reduced to a very low level, the lead-zinc smelting lean slag phase in the upper layer after reduction is rich in silicon dioxide, reaching 28%-55%, the iron content is synchronously reduced, and a stable phase mainly composed of silicate minerals (spinel and tremolite) is formed, thereby meeting the rigid demand for high-silicon and low-metal raw materials for preparing the glass-ceramic precursor. Moreover, the low-heavy-metal and high-silicon lead-zinc smelting lean slag obtained after reduction and leanization can stably synthesize the glass-ceramic precursor with fly ash by melting and solidification, so that the original smelting slag is changed from an environmental burden to a resource carrier.

[0029] In the embodiment of the present application, biomass charcoal such as straw and wood chip pyrolysis products can be added to the molten lead-zinc smelting slag to replace part of the coke, and the high reactivity and pore structure of the biomass charcoal can accelerate the high-temperature reduction process. In the embodiment of the present application, a small amount of nitrogen can be introduced into the molten lead-zinc smelting slag to accelerate the diffusion of the reducing agent and the aggregation and settlement of the metal droplets, shorten the subsequent standing and layering time, and improve the lead-zinc recovery efficiency. In the embodiment of the present application, quartz sand or limestone can be added to the molten lead-zinc smelting slag during the reduction process to adjust the silicon-calcium ratio in the lead-zinc smelting depleted slag, so that it is more suitable for the SiO2 / CaO ≈ 1.5-2.5 microcrystalline glass formation interval, which helps to reduce the formulation adjustment cost during the preparation of microcrystalline glass precursor.

[0030] In the embodiment of the present application, the zinc-containing dust generated during the reduction process can be captured by a bag filter and then directly returned to the lead-zinc smelting main process to recover zinc metal, thereby reducing the emission of heavy metals into the atmosphere.

[0031] In the embodiment of the present application, the reduction process is carried out in a reduction furnace, and the high-temperature flue gas discharged from the reduction furnace has a temperature > 1000 ℃. The waste heat boiler can generate steam using the heat carried by the steam to heat the lead-zinc smelting depleted slag and the municipal solid waste incineration fly ash, thereby realizing energy self-circulation.

[0032] In the embodiment of the present application, the total content of lead and zinc in the prepared lead-zinc smelting depleted slag is 0.5 %, 0.8 %, 1.0 %, 1.2 %, 1.4 %, 1.6 %, 1.8 %; the content of iron is 1 %, 2 %, 3 %, 4 %, 5 %, 6 %, 7 %, 8 %, 9 %; and the content of silicon dioxide is 28 %, 30 %, 32 %, 34 %, 36 %, 38 %, 40 %, 44 %, 46 %, 48 %, 50 %, 52 %, 55 %.

[0033] In the embodiment of the present application, the lead-zinc smelting depleted slag further includes calcium with a content of less than 10 % and magnesium with a content of less than 3 %.

[0034] For example, the lead-zinc smelting depleted slag further includes calcium with a content of 1 %, 2 %, 3 %, 4 %, 5 %, 6 %, 7 %, 8 %, 9 %, and magnesium with a content of 0.5 %, 1.0 %, 1.5 %, 2.0 %, 2.5 %.

[0035] In the embodiment of the present application, the total amount of lead and zinc in the lead-zinc smelting lean slag is less than 2%, so that the heavy metals are completely sealed by the glass phase during melting, the leaching toxicity tends to be zero, and excessive metals are avoided to destroy the stability of the silicate network; the high iron content promotes the generation of spinel crystal nucleus, which helps to enhance the mechanical strength of the glass-ceramics; the silicon dioxide content in the lead-zinc smelting lean slag can cover the formation requirements of different glass-ceramics, for example, low-silicon slag is suitable for high-calcium fly ash, high-silicon slag is compatible with low-silicon fly ash, and the polymerization degree of the melt is always in the best range. Calcium as a network modifier can reduce the melting temperature, and magnesium can inhibit the glass phase separation, both of which can improve the thermal stability of the glass-ceramics precursor and provide a basis for the subsequent low-temperature crystallization of the glass-ceramics.

[0036] In the embodiment of the present application, the household waste incineration fly ash at least contains calcium oxide, magnesium oxide, silicon dioxide, iron oxide, aluminum oxide, zinc, lead, copper, chromium and nickel.

[0037] The multi-component of the household waste incineration fly ash combines with the silicate network of the lean slag during high-temperature melting, and can form a stable mineral phase. Among them, the chlorides rich in fly ash volatilize during melting, which can avoid the destruction of glass structure by chloride ions, and reduce the load of flue gas treatment. Fly ash can also supplement the missing aluminum oxide in lean slag, thereby enhancing the glass network polymerization degree and improving the anti-crystallization ability of the glass-ceramics precursor.

[0038] In the embodiment of the present application, in step S1, the crushing and grinding steps include: The lead-zinc smelting lean slag is continuously crushed twice in the jaw crusher, and the obtained crushed lead-zinc smelting lean slag is finely ground to form the crushed and ground lead-zinc smelting lean slag.

[0039] In the embodiment of the present application, the lead-zinc smelting lean slag is crushed twice by the jaw crusher to destroy the physical package of silicate minerals on heavy metals and fully expose the lead and zinc particles. After fine grinding, the specific surface area is further increased to ensure that the heavy metals and silicate melt fully react during melting to achieve complete solidification. The finely ground lead-zinc smelting lean slag can form a uniform micron-level mixture with the household waste incineration fly ash, which helps to shorten the melting time, and the uniformity of particle size can also avoid the generation of local unmelted nucleus, eliminate heavy metal dead angles, and make the leaching toxicity of the subsequent crystallization tend to be zero.

[0040] In the embodiment of the present application, the particle size of the lead-zinc smelting lean slag after the two crushing treatments is less than 2 mm; The fineness of the crushed and ground lead-zinc smelting lean slag is 150 μm-400 μm.

[0041] In specific implementation, the particle size of the lead-zinc smelting lean slag after the two crushing treatments is 0.5 mm, 1.0 mm, 1.5 mm or 1.8 mm. The fineness of the crushed and ground lead-zinc smelting lean slag is 150 μm, 180 μm, 200 μm, 220 μm, 240 μm, 260 μm, 280 μm, 300 μm, 320 μm, 340 μm, 360 μm, 380 μm, or 400 μm.

[0042] In the embodiment of the present application, the lean slag is crushed to <2 mm to destroy the physical inclusion of heavy metals (Pb / Zn) by spinel and tremolite; after being finely ground to 150 μm-400 μm, the lead-zinc particles are fully exposed, the specific surface area is increased, and the complete solidification of heavy metals and silicate melt during melting is ensured. At the same time, the mixture of lead-zinc smelting lean slag with a fineness of 150 μm-400 μm and household waste incineration fly ash has an increased specific surface area, which helps to further shorten the melting time and improve the preparation efficiency.

[0043] In the embodiment of the present application, the melting temperature is 1400 ℃, 1450 ℃, 1500 ℃, or 1550 ℃ in step S1; melting at this temperature range can ensure the complete solidification of lead-zinc smelting lean slag and household waste fly ash, and minimize the volatilization of heavy metals; The holding time is 1 h, 1.5 h, 2 h, or 2.5 h; at this holding time, the formation of glass phase and stable solidification of metals are promoted; The molten liquid is a homogeneous high-temperature melt formed by completely melting the crushed and ground lead-zinc smelting lean slag and household waste incineration fly ash at 1400 ℃-1550 ℃; In the embodiment of the present application, the water quenching treatment step includes: The molten liquid is slowly poured into normal temperature water for water quenching.

[0044] In the embodiment of the present application, when preparing the glass-ceramic precursor, copper smelting slag can also be added, which contains a large amount of iron and silicon dioxide, and helps to further adjust the composition of the molten liquid and compatible with more types of hazardous waste to expand the solid waste disposal; In step S1, the flue gas generated by melting can be treated by bag dust removal + acid washing to recover volatilized zinc, which can be sold as a byproduct to create additional economic benefits and offset the processing cost of the glass-ceramic precursor.

[0045] In the embodiment of the present application, the mass ratio of the crushed and ground lead-zinc smelting lean slag to the household waste incineration fly ash is (3-8):1.

[0046] In specific implementation, the mass ratio of the broken and ground lead-zinc smelting depleted slag and the municipal solid waste incineration fly ash is 3:1, 4:1, 5:1, 6:1, 7:1, or 8:1. Within the ratio range, the silicon content and the melting fluidity of the mixture of the broken and ground lead-zinc smelting depleted slag and the municipal solid waste incineration fly ash can be balanced.

[0047] The method can avoid the over-dilution of the melt caused by excessive municipal solid waste incineration fly ash and the over-thickening of the melt caused by excessive broken and ground lead-zinc smelting depleted slag.

[0048] The municipal solid waste incineration fly ash is both a heavy metal solidifying agent and a flux, and the lower limit of the amount of the municipal solid waste incineration fly ash can ensure that the amount of the municipal solid waste incineration fly ash is sufficient to solidify the lead and zinc in the lead-zinc smelting depleted slag with a content of no more than 2%, and the upper limit can avoid the introduction of excessive impurities such as chlorine and sulfur, and avoid the generation of pores or cracks in the final prepared microcrystalline glass.

[0049] In the embodiment of the present application, the fineness of the microcrystalline glass precursor is 100 μm-500 μm.

[0050] In specific implementation, the fineness of the microcrystalline glass precursor is 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, or 500 μm. The microcrystalline glass precursor particles with the fineness have a homogeneous and dense structure, and in the preparation of the microcrystalline glass, the wollastonite crystals grow along the particle boundaries in a directional manner, permanently locking the lead and zinc and other heavy metals in the crystal lattice. The lower limit (≥100 μm) of the fineness ensures that the microcrystalline glass precursor particles have sufficient mechanical strength to resist crystallization stress and avoid the leakage of heavy metals caused by microcracks, and the upper limit (≤500 μm) ensures that there is no unreacted nucleus residue in the microcrystalline glass precursor particles, eliminating dead angles.

[0051] The embodiment of the present application also provides a microcrystalline glass precursor, which is obtained by the preparation method.

[0052] The lead, zinc and other heavy metals in the microcrystalline glass precursor prepared in the embodiment of the present application are double-locked by the silicate glass phase and the wollastonite crystals formed by subsequent crystallization, and the leaching toxicity is greatly reduced, meeting the most stringent environmental protection regulations. The volatile impurities such as chlorine and sulfur in the municipal solid waste incineration fly ash can be completely removed in the melting stage, avoiding the release of harmful gases in the use process of the end product. Moreover, the microcrystalline glass precursor prepared in the embodiment of the present application can be directly nucleated and crystallized at 650 ℃-950 ℃ without additional additives.

[0053] The embodiment of the present application also provides an application of the microcrystalline glass precursor in the preparation of microcrystalline glass, The microcrystalline glass precursor is used for nucleating the preparation of microcrystalline glass at a transition temperature. The transition temperature is 650-950 ℃. The main crystal phase of the glass-ceramics is wollastonite, the bending strength is 48-50 MPa, and the compressive strength is 100-105 MPa.

[0054] In specific implementation, the transition temperature is 650 ℃, 700 ℃, 750 ℃, 800 ℃, 850 ℃, 900 ℃ or 950 ℃. At the transition temperature, the heavy metals (Pb, Zn, etc.) in the glass-ceramics precursor are chemically bonded by the crystal structure of wollastonite (CaSiO3), forming a stable phase similar to natural minerals. Compared with physical packaging, the heavy metals in the crystal lattice cannot be dissolved in extreme environments such as acid rain and freeze-thaw. The wollastonite main crystal phase gives the glass-ceramics a biomimetic mineral structure, with a bending strength (48-50 MPa) and a compressive strength (100-105 MPa) that exceed those of marble (bending strength ≈ 30 MPa) and are equivalent to those of granite (50 MPa), but the price is lower, and the application can achieve the environmental protection goal and reduce the cost of glass-ceramics application.

[0055] The prepared glass-ceramics can be directly cut into curtain wall panels, anti-static floor tiles and other high-end building materials.

[0056] In order to enable those skilled in the art to more clearly understand the present application, the following examples are used to illustrate the glass-ceramics precursor, the preparation method and the application thereof in the preparation of glass-ceramics.

[0057] Example 1 A glass-ceramics precursor is prepared, comprising: (1) directly selecting a lead-zinc smelting plant lean slag, wherein the lead content is 0.8 %, the zinc content is 0.2 %, the iron content is 6.47 %, the calcium content is 9 %, the magnesium content is 2.6 %, and the silicate minerals such as spinel, wollastonite, tremolite and iron almandine account for more than 97 %; the lead-zinc smelting lean slag is continuously crushed twice by using a jaw crusher to obtain fine particles with a particle size of less than 2 mm, and then the fine particles are finely ground to obtain a lead-zinc smelting lean slag powder with a fineness of -400 μm; (2) mixing the lead-zinc smelting lean slag powder and household waste incineration fly ash at a mass ratio of 8:1, melting at 1500 ℃, and forming a molten liquid after 2 h of melting and holding; (3) slowly flowing the molten liquid into water at room temperature for water quenching treatment, crushing, drying and finely grinding the obtained water-quenched slag to obtain a glass-ceramics precursor with a fineness of -500 μm.

[0058] The glass-ceramics precursor prepared in Example 1 is directly nucleated and crystallized at 850 ℃ to obtain a glass-ceramics. The glass-ceramics precursor prepared in Example 1 is directly nucleated and crystallized at 850 ℃ to obtain a glass-ceramics.

[0059] Example 2 A glass-ceramic precursor is prepared, comprising: (1) A certain lead-zinc smelting plant output molten lead-zinc smelting slag is selected, coke is added to the molten lead-zinc smelting slag, and reduction treatment is carried out at 1300 ℃ for 2 h. After insulation and standing, the lower layer is a lead-zinc alloy and the upper layer is a lead-zinc smelting lean slag phase. After separation, the upper layer is taken to obtain the lead-zinc smelting lean slag; wherein the lead content is 1.0 %, the zinc content is 0.3 %, the iron content is 5.84 %, the calcium content is 8.5 %, the magnesium content is 2.2 %, and the silicate minerals such as spinel, wollastonite, tremolite, and grossular reach more than 97 %; (2) The lead-zinc smelting lean slag is continuously crushed twice by using a jaw crusher to obtain fine particles with a particle size of less than 2 mm, and then the fine particles are finely ground by a vertical mill to obtain a lead-zinc smelting lean slag powder with a fineness of -350 μm; (3) The lead-zinc smelting lean slag powder and household waste incineration fly ash are mixed in a mass ratio of 6:1, and then melted at 1450 ℃. After melting and insulation for 2.5 h, a molten liquid is formed; (4) The molten liquid is slowly flowed into normal temperature water for water quenching treatment. The obtained water-quenched slag is crushed, dried, and finely ground to obtain a glass-ceramic precursor with a fineness of -450 μm.

[0060] The glass-ceramic precursor prepared in Example 1 is directly nucleated and crystallized at 850 ℃ to obtain a glass-ceramic Example 3 (1) A certain lead-zinc smelting plant lean slag is directly selected, wherein the lead content is 0.8 %, the zinc content is 0.2 %, the iron content is 6.47 %, the calcium content is 9 %, the magnesium content is 2.6 %, and the silicate minerals such as spinel, wollastonite, tremolite, and grossular reach more than 97 %. The lead-zinc smelting lean slag is continuously crushed twice by using a jaw crusher to obtain fine particles with a particle size of less than 2 mm, and then the fine particles are finely ground by a vertical mill to obtain a lead-zinc smelting lean slag powder with a fineness of -400 μm; (2) The lead-zinc smelting lean slag powder and household waste incineration fly ash are mixed in a mass ratio of 3:1, and then melted at 1400 ℃. After melting and insulation for 1 h, a molten liquid is formed; (3) The molten liquid is slowly flowed into normal temperature water for water quenching treatment. The obtained water-quenched slag is crushed, dried, and finely ground to obtain a glass-ceramic precursor with a fineness of -500 μm.

[0061] Example 4 (1) Directly select the poor slag of a lead-zinc smelting plant, wherein the lead content is 0.8 %, the zinc content is 0.2 %, the iron content is 6.47 %, the calcium content is 9 %, the magnesium content is 2.6 %, and the silicate minerals such as spinel, wollastonite, tremolite, and iron almandine account for more than 97 %; the poor slag of the lead-zinc smelting plant is continuously crushed twice by using a jaw crusher to obtain fine particles with a particle size of less than 2 mm, and then the fine particles are finely ground by using a vertical mill to obtain lead-zinc smelting poor slag powder with a fineness of -250 μm; (2) The lead-zinc smelting poor slag powder and household waste incineration fly ash are mixed at a mass ratio of 5:1, and then are melted at 1550 ℃; after 1.5 h of melting and heat preservation, a molten liquid is formed; (3) The molten liquid is slowly flowed into normal temperature water to perform water quenching treatment; the obtained water-quenched slag is crushed, dried, and finely ground to obtain a glass-ceramic precursor with a fineness of -500 μm.

[0062] Comparative Example 1 (1) Directly select the poor slag of a lead-zinc smelting plant, wherein the lead content is 0.8 %, the zinc content is 0.2 %, the iron content is 6.47 %, the calcium content is 9 %, the magnesium content is 2.6 %, and the silicate minerals such as spinel, wollastonite, tremolite, and iron almandine account for more than 97 %; the poor slag of the lead-zinc smelting plant is continuously crushed twice by using a jaw crusher to obtain fine particles with a particle size of less than 2 mm, and then the fine particles are finely ground by using a vertical mill to obtain lead-zinc smelting poor slag powder with a fineness of -400 μm; (2) The lead-zinc smelting poor slag powder is melted at 1500 ℃; after 2 h of melting and heat preservation, a molten liquid is formed; (3) The molten liquid is slowly flowed into normal temperature water to perform water quenching treatment; the obtained water-quenched slag is crushed, dried, and finely ground to obtain a glass-ceramic precursor with a fineness of -500 μm.

[0063] Comparative Example 2 (1) Silica with a mass percentage of 65 %, alumina with a mass percentage of 12 %, calcium oxide with a mass percentage of 18 %, and sodium carbonate with a mass percentage of 3 % are mixed, and 2 % of a crystal nucleus agent (calcium fluoride or zinc sulfide) is added; the melting temperature is set to be between 1450 ℃ and 1500 ℃; the mixture is subjected to melting treatment, and a glass-ceramic precursor is obtained by water quenching after melting; (2) The glass-ceramic precursor obtained in step (1) is subjected to crystallization heat treatment by using a two-step sintering method; specifically, the glass-ceramic precursor is first sintered at 850 ℃-950 ℃ for 2 hours, and then is subjected to crystallization at 1080 ℃-1130 ℃ to inhibit abnormal grain growth, so as to obtain a glass-ceramic.

[0064] The glass-ceramic precursors prepared in Examples 1-4 and Comparative Example 1 are made into glass-ceramics, and the bending strength and compressive strength of the glass-ceramics in Examples 1-4 and Comparative Examples 1-2 are investigated; the investigation results are shown in Table 1.

[0065] Table 1. Bending strength and compressive strength of the glass-ceramics

[0066] According to Table 1, it can be obtained that the bending strength (49.24 MPa-53.77 MPa) and the compressive strength (103 MPa-121 MPa) of the final product of the glass-ceramics prepared by the lead-zinc smelting lean slag and the municipal solid waste incineration fly ash according to the embodiments 1-4 of the present application are significantly higher than those of the glass-ceramics prepared by the traditional formula according to the comparative example 2. This is due to the complementary components and high-temperature synergistic reaction of the lead-zinc smelting lean slag and the municipal solid waste incineration fly ash. The combination of the lead-zinc smelting lean slag and the municipal solid waste incineration fly ash can immobilize the trace metals in both of them, so as to improve the strength of the final product of the glass-ceramics.

[0067] According to the comparative example 1 and the comparative example 2, it can be obtained that the bending strength and the compressive strength of the final product of the glass-ceramics prepared by the lead-zinc smelting lean slag doped with the municipal solid waste incineration fly ash according to the embodiment 1 are greatly improved compared with those of the glass-ceramics prepared by the single lead-zinc smelting lean slag. It is proved that if the glass-ceramics precursor is prepared only by the lead-zinc smelting lean slag, the performance requirements of the glass-ceramics cannot be met. It is necessary to dope the municipal solid waste incineration fly ash, utilize the multi-component of the municipal solid waste incineration fly ash to combine with the silicate network of the lean slag in high-temperature melting, form stable mineral phase, and enhance the glass network polymerization degree, so as to greatly improve the bending strength and the compressive strength of the final product of the glass-ceramics, and meet the performance requirements of the glass-ceramics.

[0068] In summary, the glass-ceramics precursor, the preparation method and the application thereof in preparing the glass-ceramics provided by the embodiments of the present application utilize the high-silicon characteristics of the lead-zinc smelting lean slag, and prepare the glass-ceramics precursor by adding the municipal solid waste incineration fly ash which is also a hazardous waste. The lead-zinc smelting lean slag and the municipal solid waste incineration fly ash can not only immobilize the trace metals in both of them, but also improve the strength of the final product of the glass-ceramics, so as to effectively improve the utilization efficiency and the added value of the lead-zinc smelting lean slag and the municipal solid waste incineration fly ash.

[0069] Each of the embodiments in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same and similar parts of each embodiment can be referred to each other.

[0070] Although the preferred embodiments of the present application have been described, those skilled in the art can make other changes and modifications to the embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0071] Finally, it is to be understood that the phraseology or terminology such as "first" and "second" etc. used herein is merely intended to differentiate one entity or operation from another entity or operation, without necessarily requiring or implying any actual such relationship or order between such entities or operations. Moreover, the terms "comprising", "including", or any other closure, are intended to cover the non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements does not include those elements alone but can include other elements not expressly listed or even include elements inherent in such process, method, article, or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0072] The above provides a kind of glass-ceramic precursor, preparation method and its application in preparing glass-ceramics provided by the application, are introduced in detail, the principle and implementation mode of the present application are described in this paper, the above example is only used to help understand the method and its core idea of the present application;At the same time, for the general technical personnel in the art, according to the idea of the present application, there will be changes in specific implementation mode and application range, as described above, the content of the specification should not be understood as the limitation of the present application.

Claims

1. A method of preparing a glass-ceramic precursor, characterized in that, The preparation method comprises: The broken and ground lead-zinc smelting lean slag is mixed with household waste incineration fly ash, and is melted at a temperature of 1400-1550 ℃, and is kept for 1-2.5 h to form a molten liquid; The molten liquid is water quenched at room temperature, and the obtained water quenched slag is dried and crushed to obtain the glass-ceramic precursor; The total content of lead and zinc in the lead-zinc smelting lean slag is less than 2 %, the content of iron is less than 10 %, and the content of silicon dioxide is 28-55 %.

2. The method for preparing the microcrystalline glass precursor according to claim 1, characterized in that, The mass ratio of the broken and ground lead-zinc smelting lean slag to the household waste incineration fly ash is (3-8) :

1.

3. The method for preparing the microcrystalline glass precursor according to claim 1, characterized in that, The lead-zinc smelting lean slag further comprises calcium with a content less than 10 % and magnesium with a content less than 3 %.

4. The method for preparing the microcrystalline glass precursor according to claim 1, characterized in that, The household waste incineration fly ash at least comprises calcium oxide, magnesium oxide, silicon dioxide, iron oxide, aluminum oxide, zinc, lead, copper, chromium and nickel.

5. The method for preparing the microcrystalline glass precursor according to claim 1, characterized in that, The fineness of the glass-ceramic precursor is 100-500 μm.

6. The method for preparing the microcrystalline glass precursor according to claim 1, characterized in that, The breaking and grinding step comprises: The lead-zinc smelting lean slag is continuously broken twice in a jaw crusher, and the obtained broken lead-zinc smelting lean slag is finely ground to form the broken and ground lead-zinc smelting lean slag.

7. The method for preparing the microcrystalline glass precursor according to claim 6, characterized in that, The particle size of the lead-zinc smelting lean slag after the twice breaking is less than 2 mm; The fineness of the broken and ground lead-zinc smelting lean slag is 150-400 μm.

8. The method of claim 1-7, wherein the glass-ceramic precursor is prepared by the steps of: The preparation method of the lead-zinc smelting lean slag comprises: A reducing agent is added to the molten lead-zinc smelting slag, and is reduced at a temperature of 1200-1300 ℃ for 1-2 h, and after keeping and standing, the lower layer is a metal phase, and the upper layer is a lead-zinc smelting lean slag phase, and after separation, the lead-zinc smelting lean slag is obtained; The reducing agent is one of coke, coal powder and natural gas; The metal phase is a lead-zinc alloy.

9. A glass-ceramic precursor, characterized in that, The glass-ceramic precursor is obtained by the preparation method of any one of claims 1-8.

10. Use of a glass-ceramic precursor for the preparation of a glass-ceramic, characterized in that, The glass-ceramic precursor is used for nucleation preparation of glass-ceramics at a transformation temperature; The transformation temperature is 650-950 ℃; The main crystal phase of the glass-ceramics is wollastonite, the bending strength is 48-50 MPa, and the compressive strength is 100-105 MPa.

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