Comprehensive treatment method for extracting scattered metal and degrading dioxin in cooperation with slag and waste incineration fly ash

Abstract

The invention relates to a comprehensive treatment method for extracting scattered metal and degrading dioxin in cooperation with slag and waste incineration fly ash. The comprehensive treatment method comprises the following steps: mixing germanium-containing slag, iron-ore slag containing gallium and niobium and waste incineration fly ash to obtain a mixture, and adding a first reagent into the mixture to obtain a composite mixture; the first reagent is at least one of silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder; reacting the composite mixture at a first temperature and a first vacuum degree for a first time to obtain a germanium-rich product, decomposing dioxin in the waste incineration fly ash, reacting at a second temperature and a second vacuum degree for a second time, and cooling to obtain an intermediate product of which the upper layer is residues and the lower layer is a gallium-rich ferroniobium eutectic melt; and the gallium-rich ferroniobium eutectic melt is dissolved in acid, then gallium and niobium are obtained through resin adsorption separation, and recovery of scattered metal is achieved. The problems that slag is wasted, dioxin in waste incineration fly ash is difficult to treat, and secondary pollution is easily caused are solved.

Description

Technical Field

[0001] The invention relates to the technical field of resource utilization of slag and waste incineration fly ash, and in particular to a comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash. Background Art

[0002] In today's rapidly developing science and technology field, rare metals such as germanium (Ge) and gallium (Ga) have become indispensable key materials in the manufacture of semiconductors, electronic and optical devices. Their strategic value has become increasingly prominent and they have been listed as important strategic reserve resources by many countries. In particular, germanium is widely used in many cutting-edge fields such as optical fiber communications, photovoltaic industry, infrared detection technology and efficient chemical catalysis. However, as the global demand for germanium and gallium continues to rise, a reality that cannot be ignored is that the natural reserves of these two metals are extremely limited. The global reserves of germanium are only about 8,600 tons, and gallium is 280,000 tons. Their scarcity has directly led to rising market prices year by year, exacerbating the tension in resource supply.

[0003] At the same time, germanium and gallium do not exist in the form of independent mineral deposits in nature, but exist as associated elements in complex minerals such as sphalerite, which makes extraction difficult and costly. In addition, a large amount of solid waste containing germanium, gallium and niobium, such as fly ash and iron ore slag, is often directly landfilled in traditional treatment methods, which not only occupies precious land resources and increases the economic burden of landfill treatment, but also leads to a huge waste of precious resources and may cause environmental pollution problems. In particular, if the rich germanium, gallium and niobium resources of germanium-containing slag, gallium-containing and niobium-containing iron ore slag are not effectively recycled, it is undoubtedly a great disregard for natural resources.

[0004] On the other hand, the fly ash produced during the incineration of garbage is classified as hazardous waste because it contains a large amount of chloride salts, volatile heavy metals and highly toxic dioxins, which makes it extremely difficult to treat. In the existing technology, high-temperature pyrolysis incineration or melt solidification technology is often used to remove dioxins from fly ash, aiming to decompose dioxins under extreme high temperature conditions and convert them into harmless or low-toxic substances. However, there are significant technical bottlenecks in this process: although dioxins can be decomposed at high temperatures, they are easy to recombine with chloride ions to form dioxin precursors during the cooling stage, and then regenerate dioxins, which seriously threaten environmental safety and human health.

[0005] In summary, from the dual perspectives of environmental protection and efficient resource utilization, the existing methods for treating germanium-containing fly ash and waste incineration fly ash have significant shortcomings. Therefore, developing an innovative technology that can effectively recover the valuable resources in germanium-containing fly ash and inhibit the regeneration of dioxins in waste incineration fly ash is of great significance for alleviating resource shortages, reducing environmental pollution, and promoting the development of a circular economy. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag with waste incineration fly ash, so as to solve the problem that existing germanium-containing slag and gallium-niobium-iron slag cannot be effectively recycled and utilized, resulting in waste of resources, and to solve the problem that dioxins in existing waste incineration fly ash are difficult to treat and easily cause secondary pollution.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows: The comprehensive treatment method for extracting rare metals and degrading dioxins by coordinating slag with waste incineration fly ash includes the following steps: S1, mixing germanium-containing slag, gallium- and niobium-containing iron slag and waste incineration fly ash to obtain a mixture, and adding a first reagent to the mixture to obtain a composite mixture; The first reagent is at least one of silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder; S2, reacting the composite mixture for a first time at a first temperature and a first vacuum degree to obtain a volatilized germanium-rich product and decomposing dioxins in the waste incineration fly ash, and then reacting the composite mixture for a second time at a second temperature and a second vacuum degree, cooling, and obtaining a layered intermediate product; The upper layer of the intermediate product is a residue, and the lower layer is a gallium-rich niobium-iron eutectic; The second temperature is greater than the first temperature; S3. Dissolve the gallium-rich niobium-iron eutectic in acid, and then separate the gallium and niobium by resin adsorption to achieve the recovery of scattered metals.

[0008] According to the above technical means, firstly, through a specific reagent combination (silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder) and specific reaction conditions (different temperatures and vacuum degrees), the volatilization and enrichment of germanium in the slag, as well as the enrichment of gallium and niobium, are effectively promoted. Further, through acid dissolution and resin adsorption separation, high-purity recovery of gallium and niobium is achieved, thereby improving resource utilization, reducing resource waste, and achieving efficient recovery of scattered metals; secondly, in the process of separation and enrichment of scattered metals, dioxins in the fly ash of garbage incineration are also effectively decomposed, reducing dioxin emissions, which is beneficial to environmental protection and ecological safety. It solves the problem that the existing germanium-containing slag and gallium-niobium iron slag cannot be effectively recycled and utilized, resulting in waste of resources, and also solves the problem that the treatment of dioxins in the existing fly ash of garbage incineration is difficult and easy to cause secondary pollution.

[0009] The comprehensive treatment process of the present invention has a germanium recovery rate of more than 98%, and gallium and niobium are enriched by more than 20 times. Compared with the traditional method of incinerating and enriching germanium in a fuming furnace, it overcomes the low germanium recovery rate in the traditional pyrometallurgical germanium extraction and the pollution problem of a large number of fine particle pollutants generated during the pyrometallurgical process; compared with the simple wet method for recovering germanium, the vacuum reduction process greatly reduces the acid dosage and significantly reduces the discharge of wastewater and waste acid. This method is not only economical and efficient, but also environmentally friendly.

[0010] Preferably, the comprehensive treatment method further comprises: The residue is mixed with a second reagent, and the mixture is kept warm for a third time at a third temperature to obtain a microcrystalline glass liquid; The microcrystalline glass liquid is cooled to form, water quenched, and cooled to obtain fluorescent microcrystalline glass; The second reagent is at least one of yttrium oxide, europium oxide, calcium oxide, silicon dioxide and aluminum oxide.

[0011] Preferably, the third temperature is 1200°C~3000°C.

[0012] Preferably, the third time is 1 min to 15 min.

[0013] Preferably, the mass percentages of yttrium oxide, europium oxide, calcium oxide, silicon dioxide and aluminum oxide in the residue are 5% to 20%, 3% to 7%, 5% to 20%, 5% to 20% and 5% to 10%, respectively.

[0014] Preferably, the mass ratio of the residue to the second reagent is 1:1 to 1:3.

[0015] Preferably, the fluorescent glass-ceramics is used as a material for LED fluorescent lamps.

[0016] Preferably, the method for treating the residue comprises: crushing the residue and then adding a second reagent to obtain a mixed glass; The mixed glass is placed in a muffle furnace and kept at a temperature of 1200°C to 3000°C for 1 min to 15 min to obtain a microcrystalline glass liquid; The microcrystalline glass liquid is poured into the mold while it is still hot, and after cooling to form, it is taken out for heat treatment and then cooled to room temperature to obtain fluorescent microcrystalline glass.

[0017] Preferably, the mass ratio of the germanium-containing slag, the iron slag containing gallium and niobium, and the waste incineration fly ash is 5:5:1 to 20:20:1.

[0018] Preferably, the mass percentages of the silicon dioxide, borax, sodium carbonate, alumina and coke powder to the total mass of the slag and waste incineration fly ash are 10% to 20%, 5% to 15%, 5% to 15%, 5% to 20% and 2% to 15%, respectively.

[0019] Preferably, the first temperature is 500°C to 800°C.

[0020] Preferably, the first vacuum degree is 0.1Pa~103Pa.

[0021] Preferably, the first time is 0.01s~120s.

[0022] Preferably, the second temperature is 1000°C to 3000°C.

[0023] Preferably, the second vacuum degree is 0.1Pa~103Pa.

[0024] Preferably, the second time is 0.01s~120s.

[0025] Preferably, S2 specifically includes: reacting the composite mixture at a temperature of 500°C to 800°C and a vacuum degree of 0.1Pa to 103Pa for 0.01s to 120s to obtain a volatile germanium-rich product, wherein the volatile germanium chloride can promote the decomposition of dioxins in the waste incineration fly ash; after the reaction is complete, heating to 1000°C to 3000°C, reacting at a vacuum degree of 0.1Pa to 103Pa for 0.01s to 120s, and cooling to room temperature to obtain a layered intermediate product; The upper layer of the intermediate product is the residue, and the lower layer is the gallium-rich niobium-iron eutectic.

[0026] Preferably, the acid is a mixed acid of hydrochloric acid and sulfuric acid.

[0027] Preferably, the resin is a composite resin of aminophosphoric acid and amidoxime.

[0028] Preferably, S3 specifically includes: dissolving the gallium-rich niobium-iron eutectic in a mixed acid of hydrochloric acid and sulfuric acid, and then separating gallium and niobium through an adsorption separation reaction device to achieve recovery of scattered metals, wherein the adsorption separation reaction device is equipped with a composite resin of aminophosphoric acid and amidoxime.

[0029] Preferably, the concentration ratio of hydrochloric acid to sulfuric acid in the mixed acid is 0.05:1 to 1:1.

[0030] Preferably, the mass ratio of aminophosphoric acid to amidoxime in the composite resin is 1:1 to 10:1.

[0031] Beneficial effects of the present invention: The present invention relates to a comprehensive method for synergistically treating slag and waste incineration fly ash to extract scattered metals and degrade dioxins. First, through a specific reagent combination (including silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder) and reaction conditions (different temperatures and vacuum degrees), the volatilization enrichment of germanium in the slag and the enrichment of gallium and niobium are effectively promoted. Subsequently, through acid dissolution and resin adsorption separation steps, high-purity recovery of gallium and niobium is achieved, thereby improving resource utilization, reducing resource waste, and achieving efficient recovery of scattered metals. Secondly, in the separation and enrichment process of scattered metals, dioxins in waste incineration fly ash are also effectively decomposed, reducing dioxin emissions, which is beneficial to environmental protection and ecological safety. In addition, the comprehensive treatment method converts slag and waste incineration fly ash, which may have been regarded as waste, into valuable metal resources and harmless products (such as glass), which not only reduces the amount of solid waste generated, but also realizes the resource utilization of waste, which is in line with the concept of circular economy. At the same time, this method integrates the extraction of rare metals in slag, the degradation of dioxins in waste incineration fly ash, and the separation and recovery of products, realizing the integration of processes. By precisely controlling the reaction conditions, the operation steps are simplified, the processing efficiency and stability are improved, and it has the value of promotion and application in the field of resource utilization technology of slag and waste incineration fly ash. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Flow chart of the comprehensive treatment method for extracting rare metals and degrading dioxins from slag and waste incineration fly ash. DETAILED DESCRIPTION

[0033] The following will describe the embodiments of the present invention with reference to the preferred embodiments, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0034] The present invention aims to disclose a comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag with waste incineration fly ash, so as to solve the problem that the existing germanium-containing slag and gallium-niobium-iron slag cannot be effectively recycled and utilized, resulting in waste of resources, and to solve the problem that the dioxins in the existing waste incineration fly ash are difficult to treat and easily cause secondary pollution.

[0035] like Figure 1 As shown, the comprehensive treatment method for extracting rare metals and degrading dioxins by coordinating slag with waste incineration fly ash includes the following steps: S1, mixing germanium-containing slag, gallium- and niobium-containing iron slag and waste incineration fly ash to obtain a mixture, and adding a first reagent to the mixture to obtain a composite mixture; The first reagent is a mixture of silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder; S2, reacting the composite mixture for a first time at a first temperature and a first vacuum degree to obtain a volatilized germanium-rich product and decomposing dioxins in the waste incineration fly ash, and then reacting the composite mixture for a second time at a second temperature and a second vacuum degree, cooling, and obtaining a layered intermediate product; The upper layer of the intermediate product is the residue, and the lower layer is the gallium-rich niobium-iron eutectic; The second temperature is greater than the first temperature; S3. Dissolve the gallium-rich niobium-iron eutectic in acid, and then separate the gallium and niobium by resin adsorption to achieve the recovery of scattered metals.

[0036] The above method effectively promotes the volatilization and enrichment of germanium in slag, as well as the enrichment of gallium and niobium, through a specific reagent combination (silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder) and specific reaction conditions (different temperatures and vacuum degrees). Further, through acid dissolution and resin adsorption separation, high-purity recovery of gallium and niobium is achieved, thereby improving resource utilization, reducing resource waste, and achieving efficient recovery of scattered metals; secondly, in the process of separation and enrichment of scattered metals, dioxins in waste incineration fly ash are also effectively decomposed, reducing dioxin emissions, which is beneficial to environmental protection and ecological safety. The recovery rate of germanium in this process exceeds 98%, and gallium and niobium are enriched by more than 20 times. Compared with the traditional method of incineration and enrichment of germanium in the traditional fuming furnace, it overcomes the low recovery rate of germanium in the traditional pyrometallurgical extraction of germanium and the pollution problem of a large number of fine particulate pollutants generated during the pyrometallurgical process; compared with the simple wet method for recovering germanium, the vacuum reduction process greatly reduces the amount of acid used and significantly reduces the discharge of wastewater and waste acid. This method is not only economical and efficient, but also environmentally friendly.

[0037] In some embodiments, the comprehensive processing method further includes: The residue is mixed with a second reagent, and the mixture is kept warm for a third time at a third temperature to obtain a microcrystalline glass liquid; Cooling the glass-ceramic liquid into a shape, heat treating, and cooling to obtain fluorescent glass-ceramic; The second reagent is a mixture of yttrium oxide, europium oxide, calcium oxide, silicon dioxide and aluminum oxide.

[0038] In some embodiments, the third temperature is 1200°C to 3000°C.

[0039] In some embodiments, the third time is 1 min to 15 min.

[0040] In some embodiments, yttrium oxide, europium oxide, calcium oxide, silicon dioxide and aluminum oxide account for 5% to 20%, 3% to 7%, 5% to 20%, 5% to 20% and 5% to 10% of the residue by mass, respectively.

[0041] In some embodiments, the mass ratio of the residue to the second reagent is 1:1 to 1:3.

[0042] In some embodiments, fluorescent micro-ceramic glass is used as a material for LED fluorescent lamps.

[0043] Exemplarily, the method for treating the residue includes: crushing the residue, and then adding a second reagent to obtain a mixed glass; The mixed glass is placed in a muffle furnace and kept at a temperature of 1200°C to 3000°C for 1 min to 15 min to obtain a microcrystalline glass liquid; The microcrystalline glass liquid is poured into the mold while it is still hot, and after cooling to form, it is taken out for heat treatment and then cooled to room temperature to obtain fluorescent microcrystalline glass.

[0044] In some embodiments, the mass ratio of the germanium-containing slag, the iron slag containing gallium and niobium, and the waste incineration fly ash is 5:5:1 to 20:20:1.

[0045] In some embodiments, the mass percentages of silicon dioxide, borax, sodium carbonate, alumina and coke powder in the total mass of the slag and waste incineration fly ash are 10% to 20%, 5% to 15%, 5% to 15%, 5% to 20% and 2% to 15%, respectively.

[0046] In some embodiments, the first temperature is 500°C to 800°C.

[0047] In some embodiments, the first vacuum degree is 0.1 Pa~103 Pa.

[0048] In some embodiments, the first time is 0.01s~120s.

[0049] In some embodiments, the second temperature is 1000°C to 3000°C.

[0050] In some embodiments, the second vacuum degree is 0.1 Pa~103 Pa.

[0051] In some embodiments, the second time is 0.01s~120s.

[0052] Exemplarily, S2 specifically includes: reacting the composite mixture at a temperature of 500° C. to 800° C. and a vacuum degree of 0.1 Pa to 103 Pa for 0.01 s to 120 s to obtain a volatilized germanium-rich product, which can promote the decomposition of dioxins in the waste incineration fly ash; after the reaction is complete, heating to 1000° C. to 3000° C., reacting at a vacuum degree of 0.1 Pa to 103 Pa for 0.01 s to 120 s, and cooling to room temperature to obtain a layered intermediate product; The upper layer of the intermediate product is the residue, and the lower layer is the gallium-rich niobium-iron eutectic.

[0053] In some embodiments, the acid is a mixture of hydrochloric acid and sulfuric acid.

[0054] In some embodiments, the resin is a composite resin of aminophosphoric acid and amidoxime.

[0055] Exemplarily, S3 specifically includes: dissolving the gallium-rich niobium-iron eutectic in a mixed acid of hydrochloric acid and sulfuric acid, and then separating gallium and niobium through an adsorption separation reaction device to achieve recovery of scattered metals, wherein the adsorption separation reaction device is equipped with a composite resin of aminophosphoric acid and amidoxime.

[0056] In some embodiments, the concentration ratio of hydrochloric acid to sulfuric acid in the mixed acid is 0.05:1 to 1:1.

[0057] In some embodiments, the mass ratio of aminophosphoric acid to amidoxime in the composite resin is 1:1 to 10:1.

[0058] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the comprehensive treatment method for extracting rare metals and degrading dioxins from synergistic slag and waste incineration fly ash of the present invention will be further described in detail below in combination with specific embodiments and drawings. Obviously, the specific embodiments described are only part of the embodiments of the present application, not all of them. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the present application and its applications. Based on the specific embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0059] If no specific techniques or conditions are specified in the specific embodiments, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0060] like Figure 1 As shown, a comprehensive treatment method for extracting rare metals and degrading dioxins by coordinating slag with waste incineration fly ash comprises the following steps: S1, mixing 10 g of germanium-containing slag, 10 g of iron slag containing gallium and niobium, and 2 g of waste incineration fly ash to obtain a mixture, and adding 4.8 g of the first reagent to the mixture to obtain a composite mixed powder; The first reagent is a mixture of silicon dioxide, borax, calcium oxide and coke powder, in which the mass percentages of the slag and the waste incineration fly ash are 15%, 8%, 5% and 5% respectively; S2, placing the composite mixed powder obtained in S1 in a flash Joule heat reactor, reacting for 60 seconds at a temperature of 650° C. and a vacuum degree of 100 Pa to volatilize germanium chloride, zinc chloride and lead chloride to obtain a volatilized germanium-rich product, germanium chloride, i.e., vacuum chlorinated volatiles; at the same time, combining the vacuum conditions, the removal of the chlorine source and the synergistic effect of the reaction of germanium and germanium chloride to promote the decomposition of dioxins in the waste incineration fly ash, and after the reaction is complete, continue to heat up to 2000° C., keep the vacuum degree unchanged, react for 120 seconds, perform quenching treatment, and cool to room temperature to obtain a layered intermediate product; The upper layer of the intermediate product is the residue (i.e., the gallium- and niobium-rich roasting residue), and the lower layer is the gallium-rich niobium-iron eutectic; S3, dissolving the gallium-rich niobium-iron eutectic obtained in the lower layer in S2 in a mixed acid of hydrochloric acid and sulfuric acid at a concentration of 1:1, and then placing it in an adsorption separation reaction device filled with a composite resin of aminophosphoric acid and amidoxime at a mass ratio of 5:1, and performing adsorption separation to obtain gallium and niobium, thereby realizing the recovery of scattered metals; S4, crushing the upper residue obtained in S2, and adding 15 g of the second reagent to obtain a mixed glass; The mixed glass was placed in a muffle furnace and kept at 2100°C for 10 min to obtain a microcrystalline glass liquid. Pour the hot microcrystalline glass liquid into the mold, cool it down to form, take it out for water quenching, and then cool it to room temperature to obtain fluorescent microcrystalline glass, which can be used as materials for LED fluorescent lamps, etc. The second reagent is yttrium oxide, calcium oxide and silicon dioxide, and the mass percentages of yttrium oxide, calcium oxide and silicon dioxide in the residue are 10%, 5% and 5% respectively.

[0061] like Figure 1 As shown, a comprehensive treatment method for extracting rare metals and degrading dioxins by coordinating slag with waste incineration fly ash comprises the following steps: S1, mixing 20 g of germanium-containing slag, 20 g of iron slag containing gallium and niobium, and 2 g of waste incineration fly ash to obtain a mixture, and adding 13 g of the first reagent to the mixture to obtain a composite mixed powder; The first reagent is a mixture of silicon dioxide, borax, calcium oxide and coke powder, which account for 10%, 10%, 10% and 5% of the total mass of the slag and the waste incineration fly ash respectively; S2, placing the composite mixed powder obtained in S1 in a flash Joule heat reactor, reacting for 60 seconds at a temperature of 600° C. and a vacuum degree of 10 Pa to volatilize germanium chloride, zinc chloride and lead chloride to obtain a volatile germanium-rich product, germanium chloride, i.e., vacuum chlorinated volatiles. Meanwhile, germanium chloride can promote the decomposition of dioxins in the fly ash of garbage incineration. After the reaction is complete, continue to heat up to 2000° C., keep the vacuum degree unchanged, react for 120 seconds, perform quenching treatment, and cool to room temperature to obtain a layered intermediate product; The upper layer of the intermediate product is the residue, and the lower layer is the gallium-rich niobium-iron eutectic; S3, dissolving the gallium-rich niobium-iron eutectic obtained in the lower layer in S2 in a mixed acid of hydrochloric acid and sulfuric acid at a concentration of 1:1, and then placing it in an adsorption separation reaction device filled with a composite resin of aminophosphoric acid and amidoxime at a mass ratio of 7:1, to perform adsorption separation to obtain gallium and niobium, thereby realizing the recovery of scattered metals; S4, crushing the upper residue obtained in S2, and adding 10 g of the second reagent to obtain a mixed glass; The mixed glass was placed in a muffle furnace and kept at 2100°C for 10 min to obtain a microcrystalline glass liquid. Pour the hot microcrystalline glass liquid into the mold, cool it down to form, take it out for water quenching, and then cool it to room temperature to obtain fluorescent microcrystalline glass, which can be used as materials for LED fluorescent lamps, etc. The second reagent is yttrium oxide, calcium oxide and silicon dioxide, and the mass percentages of yttrium oxide, calcium oxide and silicon dioxide in the residue are 8%, 5% and 10% respectively.

[0062] like Figure 1 As shown, a comprehensive treatment method for extracting rare metals and degrading dioxins by coordinating slag with waste incineration fly ash comprises the following steps: S1, 8 g of germanium-containing slag, 8 g of iron slag containing gallium and niobium, and 2 g of waste incineration fly ash are mixed to obtain a mixture, and 4.8 g of the first reagent is added to the mixture to obtain a composite mixed powder; The first reagent is a mixture of silicon dioxide, borax, calcium oxide and coke powder, in which the mass percentages of the slag and the waste incineration fly ash are 10%, 5%, 8% and 5% respectively; S2, placing the composite mixed powder obtained in S1 in a flash Joule heat reactor, reacting for 60 seconds at a temperature of 650° C. and a vacuum degree of 10 Pa to volatilize germanium chloride, zinc chloride and lead chloride to obtain a volatilized germanium-rich product, germanium chloride. At the same time, the vacuum condition, the removal of the chlorine source and the synergistic effect of the reaction of germanium and germanium chloride promote the decomposition of dioxins in the waste incineration fly ash. After the reaction is complete, continue to heat up to 2000° C., keep the vacuum degree unchanged, react for 120 seconds, perform quenching treatment, and cool to room temperature to obtain a layered intermediate product; The upper layer of the intermediate product is the residue, and the lower layer is the gallium-rich niobium-iron eutectic; S3, dissolving the gallium-rich niobium-iron eutectic obtained in the lower layer in S2 in a mixed acid of hydrochloric acid and sulfuric acid at a concentration of 1:1, and then placing it in an adsorption separation reaction device filled with a composite resin of aminophosphoric acid and amidoxime at a mass ratio of 5:1, and performing adsorption separation to obtain gallium and niobium, thereby realizing the recovery of scattered metals; S4, crushing the upper residue obtained in S2, and adding 15 g of the second reagent to obtain a mixed glass; The mixed glass was placed in a muffle furnace and kept at 2100°C for 10 min to obtain a microcrystalline glass liquid. Pour the hot microcrystalline glass liquid into the mold, cool it down to form, take it out for water quenching, and then cool it to room temperature to obtain fluorescent microcrystalline glass, which can be used as materials for LED fluorescent lamps, etc. The second reagent is yttrium oxide, calcium oxide and silicon dioxide, and the mass percentages of yttrium oxide, calcium oxide and silicon dioxide in the residue are 5%, 10% and 5% respectively.

[0063] Detection and analysis: 1) The germanium-containing slag, the gallium- and niobium-containing iron slag, and the waste incineration fly ash used in S1 of Examples 1 to 3 were analyzed by XRF, and the results are shown in Table 1.

[0064] Table 1 Element analysis results of germanium-containing slag, gallium- and niobium-containing iron slag and waste incineration fly ash From the analysis in Table 1, it can be seen that the germanium content in the germanium-containing slag is 0.56%.

[0065] 2) The samples of germanium-containing slag, gallium- and niobium-containing iron slag, vacuum chlorinated volatiles and gallium- and niobium-rich roasting residues obtained in Example 1 were respectively heated to 150 °C. o The contents of Ge, Ga and Nb were determined by nitric acid digestion of C. The results are shown in Table 2.

[0066] Table 2 Results of Ge, Ga and Nb contents in each sample From the analysis in Table 2, it can be seen that the recovery rate of germanium exceeds 98%, and the enrichment of gallium and niobium is more than 5 times.

[0067] 3) Analysis of dioxin content in the waste incineration fly ash used in S1 of Example 1 and the residue of S2 Table 3 Results of dioxin content in fly ash and residues from waste incineration In summary, the comprehensive treatment method of the present invention for extracting rare metals and degrading dioxins by synergizing slag with waste incineration fly ash, firstly, through a specific reagent combination (silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder) and specific reaction conditions (different temperatures and vacuum degrees), effectively promotes the volatilization or enrichment of rare metal elements such as germanium, gallium and niobium in the slag, so that these rare metals can be more easily separated from the mixture. In particular, through the steps of acid dissolution and resin adsorption separation, high-purity recovery of gallium and niobium is achieved, resource utilization is improved, resource waste is reduced, and efficient recovery of rare metals is achieved; secondly, during the treatment process, by controlling the reaction conditions (such as temperature, vacuum degree, etc.), not only can rare metals be extracted, but also harmful substances such as dioxins in waste incineration fly ash can be effectively decomposed at the same time. Dioxins are highly toxic substances produced during waste incineration and have long-term harm to human health and the environment. This method reduces the emission of dioxins through an integrated treatment method, which is beneficial to environmental protection and ecological safety; thirdly, this method converts slag and waste incineration fly ash, which may have been regarded as waste, into valuable metal resources and harmless products (such as glass), which not only reduces the amount of solid waste generated, but also realizes the resource utilization of waste, which is in line with the concept of circular economy; fourthly, this treatment method integrates the extraction of rare metals in slag, the degradation of dioxins in waste incineration fly ash, and the separation and recovery of products, realizing the integration of processes with high process integration. At the same time, by precisely controlling the reaction conditions, the operation steps are simplified, and the treatment efficiency and stability are improved; finally, compared with the traditional method of separately treating slag and waste incineration fly ash, this comprehensive treatment method has obvious advantages in reducing environmental pollution and improving resource recovery rate. At the same time, due to the recovery of rare metals and the resource utilization of waste, this method also has significant economic and social benefits, and has the advantages of environmental friendliness and significant economic benefits. The comprehensive treatment method of the present invention for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash shows outstanding beneficial effects in resource recovery, environmental protection and economic benefits, and has promotion and application value in the technical field of resource utilization of slag and waste incineration fly ash.

[0068] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or change made by a person skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash, characterized in that: The following steps are involved: S1, mixing germanium-containing slag, gallium- and niobium-containing iron slag and waste incineration fly ash to obtain a mixture, and adding a first reagent to the mixture to obtain a composite mixture; The first reagent is at least one of silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder; S2, reacting the composite mixture for a first time at a first temperature and a first vacuum degree to obtain a germanium-rich product, and decomposing dioxins in the waste incineration fly ash, and then reacting for a second time at a second temperature and a second vacuum degree, cooling, and obtaining a layered intermediate product; The upper layer of the intermediate product is a residue, and the lower layer is a gallium-rich niobium-iron eutectic; The second temperature is greater than the first temperature; S3. Dissolve the gallium-rich niobium-iron eutectic in acid, and then separate the gallium and niobium by resin adsorption to achieve the recovery of scattered metals.

2. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 1 is characterized in that: The comprehensive processing method further includes: The residue is mixed with a second reagent, and the mixture is kept warm for a third time at a third temperature to obtain a microcrystalline glass liquid; Cooling the glass-ceramic liquid into a shape, heat treating, and cooling to obtain fluorescent glass-ceramic; The second reagent is at least one of yttrium oxide, europium oxide, calcium oxide, silicon dioxide and aluminum oxide.

3. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 2 is characterized in that: The third temperature is 1200° C. to 3000° C.; And / or, the third time is 1 min to 15 min.

4. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 2 is characterized in that: The mass percentages of yttrium oxide, europium oxide, calcium oxide, silicon dioxide and aluminum oxide in the residue are 5% to 20%, 3% to 7%, 5% to 20%, 5% to 20% and 5% to 10% respectively; And / or, the mass ratio of the residue to the second reagent is 1:1 to 1:3; And / or, the fluorescent glass-ceramics is used as a material for LED fluorescent lamps.

5. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 1 is characterized in that: The mass ratio of the germanium-containing slag, the gallium- and niobium-containing iron slag, and the waste incineration fly ash is 5:5:1 to 20:20:1; And / or, the mass ratio of the germanium-containing slag to the iron slag containing gallium and niobium is 1:

1.

6. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 1 is characterized in that: The mass percentages of the silicon dioxide, borax, calcium oxide, aluminum oxide and coke powder in the total mass of the slag and waste incineration fly ash are 10% to 20%, 5% to 15%, 5% to 15%, 5% to 20% and 2% to 15%, respectively.

7. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 1, characterized in that: The first temperature is 500° C. to 800° C.; And / or, the first vacuum degree is 0.1Pa~10 3 Pa; And / or, the first time is 0.01s~120s.

8. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 1 is characterized in that: The second temperature is 1000° C. to 3000° C.; And / or, the second vacuum degree is 0.1 Pa~103 Pa; And / or, the second time is 0.01s~120s.

9. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 1, characterized in that: The acid is a mixed acid of hydrochloric acid and sulfuric acid; And / or, the resin is a composite resin of aminophosphoric acid and amidoxime.

10. The comprehensive treatment method for extracting rare metals and degrading dioxins by synergizing slag and waste incineration fly ash according to claim 9, characterized in that: The concentration ratio of hydrochloric acid to sulfuric acid in the mixed acid is 0.05:1 to 1:1; And / or, the mass ratio of aminophosphoric acid to amidoxime in the composite resin is 1:1 to 10:1.

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