A method for coordinating the treatment of vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic

Abstract

The present invention discloses a method for co-processing vortex furnace smoke and chain furnace smoke to enrich germanium and remove arsenic. The method comprises the following steps: (1) uniformly mixing vortex furnace smoke and chain furnace smoke in a mass ratio of 1:1 to 5 to obtain a germanium-containing material; (2) subjecting the germanium-containing material to reduction and volatilization at a temperature of 900°C to 1200°C under protective atmosphere conditions for 3 to 8 hours, and then collecting dust to obtain germanium-arsenic smoke and a volatilized residue; (3) subjecting the germanium-arsenic smoke obtained by reduction and sulfidation volatilization to oxidation and volatilization, and then collecting dust to obtain a germanium enrichment and arsenic-containing smoke. The present invention uses chain furnace smoke as a sulfur source in the volatilization process of vortex furnace smoke, carries out co-processing of chain furnace smoke and vortex furnace smoke, and achieves efficient germanium enrichment.

Description

Technical field:

[0001] The invention relates to the technical field of germanium recovery and extraction, and in particular to a method for co-processing vortex furnace smoke dust and chain furnace smoke dust to enrich germanium and remove arsenic. Background technology:

[0002] Germanium is an important strategic metal, widely used in semiconductor devices, infrared materials, optical fiber materials, catalysts and other fields.

[0003] Currently, about 50% of China's germanium production comes from the zinc smelting process, and the other 50% comes from germanium coal.

[0004] The main method of extracting germanium from germanium coal is to burn the coal in a weakly oxidizing atmosphere, obtain germanium enrichment from the smoke, and finally extract germanium through chlorination distillation.

[0005] There are two main types of combustion devices used to treat germanium coal using the reduction volatilization process: the chain furnace and the vortex furnace. The chain furnace uses a fixed-bed combustion process, eliminating the need for crushing and grinding the raw coal, simplifying the process. However, the combustion process produces a low dust rate and is inefficient. The germanium grade of the chain furnace dust produced is higher than that of the vortex furnace. The vortex furnace uses suspended intensified smelting equipment, drying the germanium coal and grinding it into a fine powder for combustion. While it has high processing capacity and high dust production, the germanium grade of the vortex furnace dust produced is lower.

[0006] Whether it is the chain furnace dust or the vortex furnace dust, when the subsequent chlorination distillation process is used to extract germanium, since part of the germanium in the dust exists in the form of silicon-germanium solid solution and tetragonal germanium dioxide, this part of the germanium is difficult to dissolve during the chlorination distillation process, resulting in low efficiency of the existing chlorination distillation process; at the same time, due to the low grade of germanium, the consumption of auxiliary materials in the chlorination distillation process is large, and due to the high arsenic content in the dust, a large amount of oxidant (MnO2 or Cl2) needs to be added to As 3+ Oxidized to As 5+ To achieve the separation of germanium and arsenic.

[0007] In summary, the existing chlorination distillation process directly treats the smoke from vortex furnaces and chain furnaces, and has problems such as large consumption of auxiliary materials and low distillation efficiency, which need to be solved urgently. Summary of the invention:

[0008] In view of the problems of high auxiliary material consumption and low distillation efficiency in the existing chlorination distillation process that directly treats vortex furnace and chain furnace smoke, the present invention proposes a method for coordinating the treatment of vortex furnace smoke and chain furnace smoke to enrich germanium and remove arsenic. Based on the properties of "silicon is oxygen-friendly and germanium is sulfur-friendly", the high sulfur and carbon content of chain furnace smoke is utilized. By controlling the reaction atmosphere, the germanium in the chain furnace and vortex furnace smoke is volatilized in the form of GeS and GeS2, breaking through the directional dissociation of silicon-germanium solid solution; on the basis of sulfidation volatilization to enrich germanium, the sulfidation volatilization smoke is converted into solid GeO by controlling the oxidizing atmosphere, taking advantage of the high volatility of As2O3 (sublimation at 465°C) and the low volatility of hexagonal GeO2 (boiling point 1200°C). 2(s) With gaseous As2O 3(g) , achieving efficient separation of germanium and arsenic.

[0009] The object of the present invention is to provide a method for co-processing vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic, comprising the following steps:

[0010] (1) Material preparation: Mix the vortex furnace dust and the chain furnace dust in a mass ratio of 1:1 to 5 to obtain a germanium-containing material;

[0011] (2) Reduction sulfide volatilization: The germanium-containing material is subjected to reduction volatilization at a temperature of 900°C to 1200°C under protective atmosphere conditions for 3 to 8 hours, and then the germanium-arsenic smoke and volatile residue are obtained through dust collection;

[0012] (3) Oxidation and volatilization: The germanium-arsenic dust obtained by reduction and sulfidation volatilization is oxidized and volatilized, and then the germanium-enriched product and arsenic-containing dust are obtained through dust collection.

[0013] The method proposed in the present invention performs secondary enrichment of germanium in the chain furnace smoke and vortex furnace smoke before chlorination distillation, thereby improving the germanium grade in the enriched product and achieving precise control of the germanium crystal structure (germanium mainly exists in the form of easily soluble hexagonal germanium dioxide), greatly reducing the difficulty of subsequent chlorination distillation (in terms of the chlorination distillation process, the germanium grade enrichment in the smoke ash is increased by 10 times, the distillation processing volume and the amount of distillation residue will be greatly reduced by 90%, and the acid consumption and waste liquid generation will also be greatly reduced). The environmental and economic benefits are very significant.

[0014] In the above method, the main chemical reactions involved in the reduction volatilization process in step (2) are as follows:

[0015] CaSO4+4C=CaS+4CO↑

[0016] 2CaSO4+GeO2+8C=GeS2↑+2CaO+8CO↑

[0017]

[0018] As2O5+3CaS+2C=As2S3↑+3CaO+2CO↑

[0019] The main chemical reactions involved in the oxidation volatilization process in step (3) are as follows:

[0020] GeS2+3O2=GeO2+2SO2↑

[0021] 2As2S3+9O2=2As2O3↑+6SO2↑

[0022] Preferably, the vortex furnace smoke dust described in step (1) includes the following components: the vortex furnace smoke dust includes the following components: Ge 0.25~2.0wt.%, C 5~20wt.%, S1~5wt.%, As 0.25~8.0wt.%, Si 2.5~20wt.%, Ca 1~5wt.%, wherein germanium mainly exists in the form of soluble GeO2 (accounting for 50~60% of the total germanium) and insoluble GeO2 (accounting for 40~50% of the total germanium), and sulfur mainly exists in the form of calcium sulfate.

[0023] Preferably, the chain furnace smoke dust described in step (1) comprises the following components: Ge 0.5-2.5wt.%, As 0.5-5.0wt.%, C 10-45wt.%, S 5-10wt.%, Si 5-15wt.%, Ca 5-10wt.%, wherein germanium mainly exists in the form of soluble GeO2 (accounting for 65-75% of the total germanium) and insoluble GeO2 (accounting for 25-35% of the total germanium), and sulfur mainly exists in the form of calcium sulfate.

[0024] Preferably, the mass ratio of the vortex furnace smoke and the chain furnace smoke in step (1) is 1:2-4.

[0025] Preferably, the germanium-containing material in step (2) is reduced and volatilized at a temperature of 1000° C. to 1150° C. in a nitrogen atmosphere for 5 to 8 hours, and then the germanium-arsenic fume and volatile residue are obtained by dust collection.

[0026] Preferably, the oxidative volatilization conditions in step (3) are: oxidative volatilization is carried out at a temperature of 500° C. to 800° C. and in an oxidizing atmosphere for 2 to 4 hours.

[0027] More preferably, the oxidative volatilization conditions in step (3) are: oxidative volatilization is carried out at a temperature of 600° C. to 800° C. and in an oxidizing atmosphere for 2 to 3 hours.

[0028] Preferably, the oxidizing atmosphere is an air atmosphere.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] (1) The present invention uses the chain furnace dust as a sulfur source in the volatilization process of the vortex furnace dust, carries out the coordinated treatment of the chain furnace dust and the vortex furnace dust, and realizes the efficient enrichment of germanium;

[0031] (2) The present invention breaks through the technical difficulty of efficient separation of germanium from silicon and arsenic through reduction, sulfidation and oxidation volatilization;

[0032] (3) The present invention achieves precise control of the phase structure of germanium in the enriched material (germanium exists in the form of hexagonal germanium dioxide), providing high-quality raw materials for the subsequent chlorination distillation process. Description of the drawings:

[0033] Figure 1 The present invention is a process flow chart of a method for collaboratively treating vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic. Specific implementation method:

[0034] The following examples are provided to further illustrate the present invention, but are not intended to limit the present invention.

[0035] In order to make the purpose, technical solutions and advantages of the present invention clearer, the embodiments and implementation schemes of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. The following description of at least one example is actually only illustrative and in no way serves as any limitation on the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] The fuel cell membrane electrode activation method and technical effects of the present invention are described below with reference to specific embodiments.

[0037] In the following embodiments, the main components of the chain furnace smoke are: Ge 0.96wt.%, As 1.12wt.%, C 44.0wt.%, S 6.13wt.%, Ca 7.18wt.%, Si 7.5wt.%; the main components of the vortex furnace smoke are: Ge 0.72wt.%, As 1.19wt.%, C 2.34wt.%, S 0.96wt.%, Ca 1.35wt.%, Si 18.6wt.%.

[0038] Example 1:

[0039] A method for co-processing vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic comprises the following steps:

[0040] (1) Material preparation: Mix the vortex furnace dust and the chain furnace dust in a mass ratio of 1:2 to obtain the germanium-containing material;

[0041] (2) Reduction sulfide volatilization: The germanium-containing material is subjected to reduction volatilization at a temperature of 1050°C in a nitrogen atmosphere for 6 hours, and then the germanium-arsenic fume and volatile residue are obtained through dust collection;

[0042] (3) Oxidation and volatilization: The germanium-arsenic fume obtained by reduction and sulfidation volatilization is oxidized and volatilized at a temperature of 600°C in an air atmosphere for 3 hours, and then the germanium-enriched product and arsenic-containing fume are obtained through dust collection.

[0043] Example 2:

[0044] A method for co-processing vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic comprises the following steps:

[0045] (1) Material preparation: Mix the vortex furnace dust and the chain furnace dust in a mass ratio of 1:3 to obtain the germanium-containing material;

[0046] (2) Reduction sulfide volatilization: The germanium-containing material is subjected to reduction volatilization at a temperature of 1150°C in a nitrogen atmosphere for 5 hours, and then the germanium-arsenic fume and volatile residue are obtained through dust collection;

[0047] (3) Oxidation and volatilization: The germanium-arsenic fume obtained by reduction and sulfidation volatilization is oxidized and volatilized at a temperature of 700°C in an air atmosphere for 2 hours, and then the germanium-enriched product and arsenic-containing fume are obtained through dust collection.

[0048] Example 3:

[0049] A method for co-processing vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic comprises the following steps:

[0050] (1) Material preparation: Mix the vortex furnace dust and the chain furnace dust in a mass ratio of 1:4 to obtain the germanium-containing material;

[0051] (2) Reduction sulfide volatilization: The germanium-containing material is subjected to reduction volatilization at a temperature of 1000°C in a nitrogen atmosphere for 8 hours, and then the germanium-arsenic fume and volatile residue are obtained through dust collection;

[0052] (3) Oxidation and volatilization: The germanium-arsenic fume obtained by reduction and sulfidation volatilization is oxidized and volatilized at a temperature of 800°C in an air atmosphere for 3 hours, and then the germanium-enriched product and arsenic-containing fume are obtained through dust collection.

[0053] Comparative Example 1:

[0054] The experimental conditions of this comparative example are basically the same as those of Example 2, except that: vortex furnace dust is used throughout the material preparation process in step (1).

[0055] Comparative Example 2:

[0056] The experimental conditions of this comparative example are basically the same as those of Example 2, except that: in the material preparation process of step (1), the mass ratio of vortex furnace smoke dust to chain furnace smoke dust is 2:1.

[0057] Comparative Example 3:

[0058] The experimental conditions of this comparative example are basically the same as those of Example 2, except that the volatilization temperature in step (2) is 800°C.

[0059] Comparative Example 4:

[0060] The experimental conditions of this comparative example are basically the same as those of Example 2, except that step (3) of the oxidation volatilization process is not performed.

[0061] Example 4:

[0062] The same as Example 2, except that: in step (1), the mass ratio of the vortex furnace smoke dust to the chain furnace smoke dust is 1:1; in step (2), the reduction volatilization is carried out under protective atmosphere at a temperature of 1200°C for 3 hours; and in step (3), the oxidative volatilization conditions are: the temperature is 500°C and the oxidative volatilization is carried out under oxidative atmosphere for 4 hours.

[0063] Example 5:

[0064] The same as Example 2, except that: in step (1), the mass ratio of the vortex furnace smoke dust to the chain furnace smoke dust is 1:5; in step (2), the temperature is 900°C and the reduction volatilization is carried out under protective atmosphere conditions for 8 hours; in step (3), the oxidative volatilization conditions are: the temperature is 800°C and the oxidative volatilization is carried out under oxidative atmosphere conditions for 2 hours.

[0065] The results of Examples 1-5 and Comparative Examples 1-4 are shown in Table 1.

[0066] Table 1

[0067] Ge grade (wt.%) As grade (wt.%) Ge recovery rate (%) Example 1 65.43 1.35 94.5 Example 2 66.57 1.08 95.6 Example 3 67.89 0.97 97.8 Example 4 64.37 1.24 94.9 Example 5 68.59 0.86 98.2 Comparative Example 1 63.28 1.58 65.8 Comparative Example 2 54.50 2.89 54.6 Comparative Example 3 43.80 3.59 45.6 Comparative Example 4 13.8 8.9 95.8

[0068] It can be seen from Table 1 that the volatilization efficiency of vortex furnace dust is poor when chain furnace dust is not used as a volatilization auxiliary agent for reduction sulfidation. When chain furnace dust is used as a volatilization auxiliary agent for vortex furnace dust, it can achieve a good synergistic volatilization effect. Oxidative volatilization based on synergistic sulfidation volatilization can achieve efficient separation of germanium and arsenic.

[0069] The description of the above embodiments is only used to help understand the technical solution and core ideas of the present invention. It should be pointed out that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention. These improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for co-processing vortex furnace dust and chain furnace dust to enrich germanium and remove arsenic, characterized in that: The steps include: (1) Material preparation: vortex furnace smoke dust and chain furnace smoke dust are mixed uniformly in a mass ratio of 1:1-5 to obtain a germanium-containing material, wherein the vortex furnace smoke dust comprises the following components: Ge 0.25-2.0 wt.%, C 5-20 wt.%, S 1-5 wt.%, As 0.25-8.0 wt.%, Si 2.5-20 wt.%, Ca 1-5 wt.%, and the sulfur mainly exists in the form of calcium sulfate; the chain furnace smoke dust comprises the following components: Ge 0.5-2.5 wt.%, As 0.5-5.0 wt.%, C 10-45 wt.%, S 5-10 wt.%, Si 5-15 wt.%, Ca 5-10 wt.%, and the sulfur mainly exists in the form of calcium sulfate; (2) Reduction sulfide volatilization: The germanium-containing material is subjected to reduction volatilization at a temperature of 900°C to 1200°C in a nitrogen atmosphere for 3 to 8 hours, and then the germanium-arsenic fume and volatile residue are obtained through dust collection; (3) Oxidation volatilization: The germanium-arsenic smoke obtained by reduction sulfide volatilization is subjected to oxidation volatilization, and then the germanium-enriched product and the arsenic-containing smoke are obtained through dust collection. The oxidation volatilization conditions are: oxidation volatilization is carried out at a temperature of 500°C to 800°C and an oxidizing atmosphere for 2 to 4 hours.

2. The method according to claim 1, characterized in that The mass ratio of the vortex furnace smoke and the chain furnace smoke in step (1) is 1:2~4.

3. The method according to claim 1, characterized in that The germanium-containing material described in step (2) is reduced and volatilized at a temperature of 1000°C to 1150°C in a nitrogen atmosphere for 5 to 8 hours, and then germanium-arsenic smoke and volatile residue are obtained through dust collection.

4. The method according to claim 1, wherein The oxidative volatilization conditions in step (3) are: oxidative volatilization is carried out at a temperature of 600°C to 800°C and in an oxidizing atmosphere for 2 to 3 hours.

5. The method according to claim 1 or 4, characterized in that The oxidizing atmosphere is air atmosphere.

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