Method for cooperatively treating copper-nickel waste residues and arsenic-containing waste

Abstract

The invention discloses a method for cooperatively treating copper-nickel waste residues and arsenic-containing waste, and belongs to the technical field of solid hazardous waste resourceful treatment in the metallurgical industry. The treatment method comprises the following steps: mixing the copper-nickel waste slag, the arsenic-containing waste material, a reducing agent, a vulcanizing agent and a solvent, performing reduction vulcanization smelting, cooling, and layering to obtain low-density smelting slag, medium-density matte and high-density nickel-containing alloy. The method is short in technological process and can be directly used for separating copper and nickel, and reduction, harmlessness and recycling of the copper-nickel waste residues and the arsenic-containing waste are achieved.

Description

Technical Field

[0001] The invention relates to a method for collaboratively treating copper-nickel waste slag and arsenic-containing waste, belonging to the technical field of resource treatment of solid and hazardous waste in the metallurgical industry. Background Art

[0002] Copper-nickel waste containing precious metals is a hazardous waste. If it is not properly disposed, it will cause secondary pollution and have a huge impact on the ecological environment and human health. At the same time, the above wastes all contain useful substances and have a high recycling value. If they can be centrally processed and the useful components can be recovered, it will not only obtain considerable economic benefits, but also solve the pollution problem.

[0003] At present, the main methods for recycling and utilizing copper-nickel waste containing precious metals are hydrometallurgical process and pyrometallurgical process. The hydrometallurgical process has a long process flow, produces a large amount of wastewater, does not reduce the amount of waste, and the final leaching residue is still a hazardous waste and needs further treatment, so the economic benefits are poor. The pyrometallurgical process mainly produces low-grade nickel matte containing copper and precious metals through reduction sulfide smelting enrichment.

[0004] At present, there are two main processes for separating copper and nickel from low-grade nickel matte containing copper and precious metals. One is to use converter blowing to produce metallized high-grade nickel matte, and then use high-matte grinding and flotation and magnetic separation to obtain nickel sulfide, copper sulfide and copper-nickel alloy, which are respectively sent to the nickel smelting system, copper smelting system and precious metal smelting system. This process is long and requires large equipment investment, which is not conducive to industrialization. The other is to use oxygen pressure leaching to obtain a copper-nickel-iron mixed solution and a leached slag containing precious metals, and the copper-nickel-iron mixed solution is separated by wet processes such as extraction and impurity removal. However, this process is long, has many steps, and has a low recovery rate of valuable metals.

[0005] At the same time, arsenic-containing waste residues are hazardous wastes with high toxicity, high pollution and high permeability. Long-term storage will pollute the atmosphere and groundwater, thus causing harm to the human body. Currently, some arsenic-containing waste residues are incinerated or solidified and landfilled, which does not achieve the treatment goals of "resource utilization, reduction and harmlessness".

[0006] Therefore, how to quickly and efficiently recycle copper-nickel waste slag and resource-recycle, reduce and harmlessly treat arsenic-containing waste slag to meet the needs of environmental protection and resource recovery is a major focus of solid waste resource utilization. Summary of the invention

[0007] In view of the problems existing in the above-mentioned prior art, one of the objects of the present invention is to provide a method for the coordinated treatment of copper-nickel waste slag and arsenic-containing waste. The method has a short process flow and can be directly used to separate copper and nickel. The smelting products are closely connected with the smelting of copper and the smelting of precious metals. The material turnover is fast, the process is simple and efficient, the raw materials have strong adaptability, the equipment is simple, and it is very easy to realize industrialization.

[0008] In order to achieve the above object, the first aspect of the present invention is to provide a method for co-processing copper-nickel waste slag and arsenic-containing waste, the method comprising: Copper-nickel waste slag, arsenic-containing waste, reducing agent, sulfiding agent and solvent are mixed and then reduced and sulfided and smelted, and then cooled and layered to obtain low-density smelting slag, medium-density matte and high-density nickel-containing alloy.

[0009] The innovative point of the present invention is that after the introduction of arsenic-containing waste, copper and nickel in copper-nickel waste slag can be separated, and copper and nickel can be separated according to the difference in geochemical affinity of copper, nickel and arsenic. The present invention reduces and sulfides and smelts copper-nickel waste slag, arsenic-containing waste, reducing agent, sulfiding agent and solvent. Due to the different densities of the matte layer, nickel-containing alloy layer and smelting slag layer, stratification can be achieved during the cooling and standing process to obtain a copper-enriched matte layer and a nickel- and arsenic-enriched alloy layer, thereby reducing the copper-nickel separation process. The method provided by the present invention not only performs harmless treatment on arsenic-containing waste, but also separates copper and nickel in copper-nickel waste slag.

[0010] In a preferred embodiment, the temperature of the reduction sulfidation smelting is 1200-1350°C.

[0011] In a preferred embodiment, relative to 100 parts by weight of the copper-nickel waste slag, the amount of the arsenic-containing waste is 10 to 20 parts by weight, the amount of the reducing agent is 5 to 30 parts by weight, the amount of the sulfiding agent is 5 to 20 parts by weight, and the amount of the solvent is 3 to 20 parts by weight.

[0012] In a preferred embodiment, the copper-nickel waste slag also contains precious metals, and the precious metals are selected from at least one of gold, platinum, palladium, rhodium, ruthenium, osmium and iridium. The inventors have found that the copper-nickel waste slag containing precious metals can also be enriched when the copper-nickel waste slag containing precious metals is subjected to reduction sulfidation smelting. When the copper-nickel waste slag containing precious metals is used, low-density smelting slag, medium-density matte and high-density alloy layer containing precious metals and nickel can be obtained by layering after cooling.

[0013] In a preferred embodiment, the content of copper in the copper-nickel waste slag is 0.5-20wt%, and the content of nickel is 0.5-20wt%.

[0014] In a preferred embodiment, the content of arsenic in the arsenic-containing waste is 1-10wt%.

[0015] In a preferred embodiment, the content of precious metals in the copper-nickel waste slag is ≥1 g / t.

[0016] In a preferred embodiment, the copper-nickel waste slag is selected from at least one of electroplating sludge, wet leaching slag and pyrometallurgical slag.

[0017] In a preferred embodiment, the arsenic-containing waste is selected from at least one of arsenic-containing smelting dust, arsenic-containing fly ash, arsenic-containing wet leaching slag and arsenic matte.

[0018] In a preferred embodiment, the reducing agent is selected from at least one of carbon powder, coke, starch and coal powder.

[0019] In a preferred embodiment, the vulcanizing agent is selected from at least one of copper matte, nickel matte, sodium sulfide, zinc sulfide, pyrite, gypsum, sulfur and sodium sulfate.

[0020] In a preferred embodiment, the solvent is selected from at least one of quartz, calcium oxide, limestone, fluorite, borax and bentonite.

[0021] In a preferred solution, the particle sizes of the copper-nickel waste slag, the arsenic-containing waste, the reducing agent, the sulfiding agent and the solvent are all ≤0.15 mm. Controlling the particle size can make the materials mix more evenly, reduce entrainment during smelting and settling, and achieve better stratification effect.

[0022] In a preferred embodiment, the method further comprises drying the copper-nickel waste slag and the arsenic-containing waste before performing the reduction sulfide smelting, wherein the drying makes the moisture content of the copper-nickel waste slag and the arsenic-containing waste both ≤1wt%.

[0023] In a preferred embodiment, the drying conditions include: a temperature of 90-110° C. and a time of 20-28 hours.

[0024] In a preferred embodiment, relative to 100 parts by weight of the copper-nickel waste slag, the amount of the arsenic-containing waste is 10-15 parts by weight, the amount of the reducing agent is 5-15 parts by weight, the amount of the sulfiding agent is 10-20 parts by weight, and the amount of the solvent is 3-18 parts by weight. Under this condition, the stratification effect is good, the copper grade in the matte is high, the nickel and precious metal grades in the alloy layer are high, and the subsequent copper smelting and precious metal smelting processing volume is reduced. In addition, when the amount of reducing agent is insufficient, the arsenic-containing waste will be easily volatilized into the flue gas, and if the reducing atmosphere is too strong, the alloy layer yield will increase, the nickel and precious metal grades will be reduced, and the subsequent precious metal processing scale will be increased.

[0025] In the preferred solution, the reduction sulfidation smelting temperature is 1250-1300°C and the time is 3-6 hours. If the temperature is too low, the viscosity of the alloy layer and the matte layer is large, and the two-phase entrainment is serious, which affects the separation effect. If the temperature is too high, the mutual solubility of the matte layer and the alloy layer becomes larger, which also affects the separation effect of copper, nickel and precious metals.

[0026] The present invention provides a process flow chart of the method, see Figure 1 .

[0027] Compared with the prior art, the present invention has at least the following advantages: The present invention adopts a one-step pyrometallurgical smelting process to obtain smelting slag, matte and alloy containing precious metals, realizing the reduction, harmlessness and resource utilization of copper-nickel waste slag and arsenic-containing waste; secondly, the pyrometallurgical smelting process realizes the separation of copper and nickel and the enrichment of precious metals, copper enters the matte layer, and precious metals and nickel enter the alloy layer. Due to their different densities, the two are separated during the cooling and standing process, reducing the copper-nickel separation process and facilitating subsequent processing. The matte layer obtained by smelting enters the copper pyrometallurgical smelting system, and the alloy layer containing precious metals enters the precious metal wet leaching system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0029] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0030] In the present invention, room temperature refers to 25±2°C.

[0031] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited to the following specific embodiments. Obviously, the embodiments described below are only a part of the embodiments, and all other embodiments obtained by professionals in this field without creative work still belong to the protection scope of the present invention.

[0032] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0033] Example 1 (1) Dry the gold-containing copper-nickel electroplating sludge and the arsenic-containing smelting fume at 105° C. to a moisture content of less than 1 wt %, grind them into powder and pass them through a 100-mesh sieve for later use; The content of copper in electroplating sludge is 5wt%, the content of nickel is 4wt%, and the content of gold is 4g / t; the content of arsenic in arsenic-containing smelting dust is 8wt%; (2) Weigh 200 g of sieved gold-containing copper-nickel electroplating sludge, 25 g of sieved arsenic-containing smelting dust, 14 g of coke powder, 30 g of sodium sulfide, and 30 g of quartz, add them into a graphite crucible and mix them evenly; the particle sizes of the coke powder, sodium sulfide, and quartz are all less than 0.15 mm; (3) Place the graphite crucible in a resistance furnace for smelting at a temperature of 1250°C for 3 hours; (4) After smelting, cool down to room temperature and take out the product. The product is divided into three layers: the upper layer (low-density layer) is the smelting slag layer, the middle layer (medium-density layer) is the matte layer, and the lower layer (high-density layer) is the silver-white alloy layer.

[0034] After testing, the smelting slag contains, by mass fraction, Cu: 0.2%, Ni: 0.3%, Au: 0.1g / t; the matte layer contains Cu: 20%, Ni: 0.5%, Au: 0.4g / t; the alloy layer contains Ni: 14%, Cu: 0.8%, Au: 30g / t.

[0035] Example 2 (1) drying the copper-nickel oxygen pressure leaching residue containing platinum and palladium and the arsenic alkaline residue (arsenic-containing fly ash) at 105° C. to a moisture content of less than 1 wt %, respectively, grinding them to powders and passing them through a 100-mesh sieve for later use; The content of copper in the oxygen pressure leaching slag is 2wt%, the content of nickel is 3wt%, the content of platinum is 80g / t, and the content of palladium is 60g / t; The content of arsenic in arsenic alkali slag is 5.5wt%; (2) Weigh 300 g of sieved copper-nickel oxygen pressure leaching slag containing platinum and palladium, 40 g of sieved arsenic alkali slag, 20 g of carbon powder, 40 g of sulfur, 30 g of quartz, and 20 g of limestone, add them into a graphite crucible and mix them evenly; the particle sizes of the carbon powder, sulfur, quartz, and limestone are all less than 0.15 mm; (3) Place the graphite crucible in a resistance furnace for smelting at a temperature of 1300°C for 4 hours; (4) After smelting, cool down to room temperature and take out the product. The product is divided into three layers: the upper layer (low-density layer) is the smelting slag layer, the middle layer (medium-density layer) is the matte layer, and the lower layer (high-density layer) is the silver-white alloy layer.

[0036] After testing, the smelting slag contains, by mass fraction, Cu: 0.3%, Ni: 0.3%, Pt: 0.1g / t, Pd: 0.1g / t; the matte layer contains Cu: 18%, Ni: 0.2%, Pt: 1g / t, Pd: 1g / t; the alloy layer contains Ni: 14%, Cu: 0.3%, Pt: 145g / t, Pd: 180g / t.

[0037] Example 3 (1) drying the gold-containing copper-nickel electroplating sludge and the arsenic-containing smelting fume at 105° C. to a moisture content of less than 1wt%, then grinding the dried gold-containing copper-nickel electroplating sludge and passing it through a 100-mesh sieve for later use; passing the dried arsenic-containing smelting fume through a 10-mesh sieve for later use; The content of copper in electroplating sludge is 8wt%, the content of nickel is 13wt%, and the content of gold is 10g / t; The content of arsenic in arsenic-containing smelting dust is 10wt%; (2) Weigh 200 g of gold-containing copper-nickel electroplating sludge that has passed a 100-mesh sieve, 25 g of arsenic-containing smelting dust that has passed a 10-mesh sieve, 14 g of coke powder, 30 g of sodium sulfide, and 30 g of quartz, add them into a graphite crucible and mix them evenly; the particle sizes of the coke powder, sodium sulfide, and quartz are all less than 0.15 mm; (3) Place the graphite crucible in a resistance furnace for smelting at a temperature of 1250°C for 3 hours; (4) After smelting, cool down to room temperature and take out the product. The product is divided into three layers: the upper layer (low-density layer) is the smelting slag layer, the middle layer (medium-density layer) is the matte layer, and the lower layer (high-density layer) is the silver-white alloy layer.

[0038] After testing, the smelting slag contains, by mass fraction, Cu: 2%, Ni: 1.8%, Au: 5g / t; the matte layer contains Cu: 25%, Ni: 3.5%, Au: 15g / t; the alloy layer contains Ni: 30%, Cu: 4.5%, Au: 70g / t.

[0039] Example 4 This example is carried out in a similar manner to that of Example 1, except that the amount of the screened arsenic-containing smelting fume in this example is adjusted to 32 g.

[0040] After smelting, the product is cooled to room temperature and taken out. The product is divided into three layers: the upper layer (low-density layer) is the smelting slag layer, the middle layer (medium-density layer) is the matte layer, and the lower layer (high-density layer) is the silver-white alloy layer.

[0041] After testing, the smelting slag contains, by mass fraction, Cu: 0.2%, Ni: 0.2%, Au: 0.3 g / t; the matte layer contains Cu: 18%, Ni: 0.3%, Au: 0.3 g / t; the alloy layer contains Ni: 8%, Cu: 3.0%, Au: 20 g / t.

[0042] Example 5 This example is carried out in a similar manner to that of Example 1, except that the amount of coke powder used in this example is adjusted to 65 g.

[0043] After smelting, the product is cooled to room temperature and taken out. The product is divided into three layers: the upper layer (low-density layer) is the smelting slag layer, the middle layer (medium-density layer) is the matte layer, and the lower layer (high-density layer) is the silver-white alloy layer.

[0044] After testing, the smelting slag contains, by mass fraction, Cu: 0.4%, Ni: 0.5%, Au: 0.3g / t; the matte layer contains Cu: 15%, Ni: 2%, Au: 1g / t; the alloy layer contains Ni: 10%, Cu: 0.4%, Au: 12g / t.

[0045] Comparative Example 1 This comparative example was carried out in a similar manner to Example 1, except that no arsenic-containing smelting fume was added during the smelting.

[0046] After smelting, the product is cooled and taken out. The product is divided into two layers, the upper layer is the smelting slag layer, and the lower layer is the black low-matte nickel layer.

[0047] After testing, based on mass fraction, the smelting slag contains Cu: 0.3%, Ni: 0.5%, Au: 0.3g / t, and the low-grade nickel matte contains Cu: 18%, Ni: 14%, Au: 20g / t.

[0048] It can be seen from the above results that the method provided by the present invention is used to synergistically treat copper-nickel waste slag and arsenic-containing waste, which can not only separate copper and nickel, but also enrich the precious metals in the copper-nickel waste slag containing precious metals.

[0049] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for co-processing copper-nickel waste slag and arsenic-containing waste, characterized in that: The method includes: Copper-nickel waste slag, arsenic-containing waste, reducing agent, sulfiding agent and solvent are mixed and then reduced and sulfided and smelted, and then cooled and layered to obtain low-density smelting slag, medium-density matte and high-density nickel-containing alloy.

2. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1, characterized in that: The temperature of the reduction sulfidation smelting is 1200-1350°C; And / or, relative to 100 parts by weight of the copper-nickel waste slag, the amount of the arsenic-containing waste is 10 to 20 parts by weight, the amount of the reducing agent is 5 to 30 parts by weight, the amount of the sulfiding agent is 5 to 20 parts by weight and the amount of the solvent is 3 to 20 parts by weight.

3. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1 or 2, characterized in that: The copper-nickel waste slag also contains precious metals, and the precious metals are selected from at least one of gold, platinum, palladium, rhodium, ruthenium, osmium and iridium.

4. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 3, characterized in that: The content of precious metals in the copper-nickel waste slag is ≥1g / t.

5. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1 or 2, characterized in that: The copper content in the copper-nickel waste slag is 0.5-20wt%, and the nickel content is 0.5-20wt%; The content of arsenic in the arsenic-containing waste is 1-10wt%.

6. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1 or 2, characterized in that: The copper-nickel waste residue is selected from at least one of electroplating sludge, wet leaching residue and pyrometallurgical slag; and / or, the arsenic-containing waste is selected from at least one of arsenic-containing smelting dust, arsenic-containing fly ash, arsenic-containing wet leaching slag and arsenic matte; And / or, the vulcanizing agent is selected from at least one of copper matte, nickel matte, sodium sulfide, zinc sulfide, pyrite, gypsum, sulfur and sodium sulfate.

7. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1 or 2, characterized in that: The solvent is selected from at least one of quartz, calcium oxide, limestone, fluorite, borax and bentonite.

8. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1 or 2, characterized in that: The particle sizes of the copper-nickel waste slag, the arsenic-containing waste, the reducing agent, the sulfiding agent and the solvent are all ≤0.15 mm.

9. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 1 or 2, characterized in that: The method also includes drying the copper-nickel waste slag and the arsenic-containing waste before performing the reduction sulfide smelting, wherein the drying makes the moisture content of the copper-nickel waste slag and the arsenic-containing waste both ≤1wt%.

10. The method for co-processing copper-nickel waste slag and arsenic-containing waste according to claim 2, characterized in that: Relative to 100 parts by weight of the copper-nickel waste slag, the amount of the arsenic-containing waste is 10 to 15 parts by weight, the amount of the reducing agent is 5 to 15 parts by weight, the amount of the sulfiding agent is 10 to 20 parts by weight, and the amount of the solvent is 3 to 18 parts by weight; And / or, the reduction sulfidation smelting temperature is 1250-1300° C. and the time is 3-6 hours.

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