A mineral processing method for recovering nickel from ultrabasic nickel tailings.

Abstract

This application provides a mineral processing method for recovering nickel from ultrabasic nickel rock tailings, relating to the field of mineral flotation. The method includes: classifying the flotation tailings of ultrabasic nickel rock to obtain coarse-grained and fine-grained products; grinding the coarse-grained product to obtain a grinding slurry; mixing the grinding slurry, depressant, collector, and frother; performing a first roughing process to obtain a first roughing concentrate and a first roughing tailings; performing a first cleaning process on the first roughing concentrate to obtain a first concentrate; performing a first scavenging process on the first roughing tailings to obtain a first tailings; performing a second roughing process on the fine-grained product, a combination of modifier, depressant, a combination of collector, and frother to obtain a second roughing tailings and a second roughing concentrate; performing a second cleaning process on the second roughing concentrate to obtain a second concentrate; and performing a second scavenging process on the second roughing tailings to obtain a second tailings. This application achieves the efficient and comprehensive utilization of strategic metallic nickel resources.

Description

Technical Field

[0001] This application relates to the field of mineral flotation, and more particularly to a mineral processing method for recovering nickel from ultrabasic rock nickel tailings. Background Technology

[0002] Nickel is a critical strategic metal globally. It is a core raw material for power batteries; the nickel content in ternary lithium batteries directly determines the battery's energy density, which is crucial for improving the range of electric vehicles. Nickel is also a core alloying element in stainless steel production; nickel-containing stainless steel possesses corrosion resistance, high-temperature resistance, and high strength. Furthermore, nickel is a key material in military equipment manufacturing; core components such as armor, engines, and transmission systems in tanks, warships, and fighter jets require nickel-based alloys to enhance their impact resistance, high-temperature resistance, and corrosion resistance.

[0003] Nickel metal primarily comes from two sources: mineral resources and recycled resources, with mineral resources currently being the most important supply channel. China's nickel ore resources are relatively scarce, and facing explosive demand from industries such as new energy and stainless steel, domestic primary nickel production consistently faces a significant shortfall. China's nickel ore deposits are mainly ultrabasic rock nickel deposits, which account for 90% of the country's total nickel ore production.

[0004] Ultrabasic nickel ore deposits often contain large amounts of serpentine and talc. Talc has a Mohs hardness of 1, making it one of the softest minerals in nature; a fingernail can easily leave a scratch on its surface. Nickel pyrrhotite and nickel-bearing pyrrhotite, on the other hand, have a Mohs hardness of 3.5-4.5. Therefore, during the grinding process, talc and some softer gangues (such as chlorite and serpentine) are easily ground into fine particles, while some nickel pyrrhotite and nickel-bearing pyrrhotite, being relatively harder, are produced as coarse particles. Consequently, during flotation, fine-grained nickel-bearing minerals are trapped, intercalated, or covered by fine-grained gangue and lost in the tailings. Coarse-grained nickel-bearing minerals, due to their intercalation, larger size, and higher specific gravity, cannot be lifted to the upper layer by air bubbles and are also lost in the tailings. For these reasons, some nickel in ultrabasic nickel ore deposits is inevitably lost in both coarse and fine-grained tailings, a phenomenon known in the industry as "running away at both ends."

[0005] Therefore, to recover scarce and valuable nickel resources from ultrabasic nickel tailings, it is necessary to "grasp both ends," that is, to grind coarse particles into finer particles to recover nickel minerals; and to fully disperse fine particles to reduce the covering effect of fine gangue on nickel-bearing minerals.

[0006] Therefore, there is an urgent need to provide a mineral processing method for recovering nickel from ultrabasic nickel tailings to solve the above-mentioned problems. Summary of the Invention

[0007] The purpose of this application is to provide a beneficiation method for recovering nickel from ultrabasic nickel tailings to solve the above-mentioned problems.

[0008] To achieve the above objectives, this application provides a mineral processing method for recovering nickel from ultrabasic nickel tailings, comprising: The flotation tailings of ultrabasic nickel rock are classified to obtain coarse-grained and fine-grained products. The coarse-grained product is ground to obtain a grinding slurry. The grinding slurry, inhibitor, collector and frother are mixed and subjected to a first roughing process to obtain a first roughing concentrate and a first roughing tailings. The first roughing concentrate is then subjected to a first cleaning process to obtain a first concentrate, and the first roughing tailings are subjected to a first scavenging process to obtain a first tailings. A combination of modifier, inhibitor, collector and frother are added sequentially to the fine-grained product for a second roughing process to obtain a second roughing tailings and a second roughing concentrate; the second roughing concentrate is then subjected to a second cleaning process to obtain a second concentrate, and the second roughing tailings are subjected to a second scavenging process to obtain a second tailings. The combined modifiers include sodium methylnaphthalene sulfonate formaldehyde condensate, sodium carbonate, and water glass; The combined collectors include xanthate collectors and di-n-butyldithiophosphate ammonium.

[0009] Optionally, the particle size of the coarse-grained product is ≥0.1 mm; The particle size of the fine-grained product is <0.1 mm; The fineness of the grinding slurry is -0.074 mm, accounting for 55%-80%.

[0010] Optionally, the inhibitor includes carboxymethyl cellulose; And / or, the collector includes xanthate; And / or, the foaming agent includes at least one of pine oil, No. 2 oil, and MIBC.

[0011] Optionally, the carboxymethyl cellulose has a molecular weight greater than 500,000 g / mol and a degree of substitution greater than 0.6.

[0012] Optionally, in the combined modifier, the mass ratio of the sodium methylnaphthalene sulfonate formaldehyde condensate, the sodium carbonate, and the water glass is 3-30:20-50:30-60.

[0013] Optionally, in the combined collector, the mass ratio of the xanthate collector to the di-n-butyldithiophosphate ammonium is 20-200:4-40.

[0014] Optionally, the combined collector includes butyl xanthate, pentyl xanthate, and di-n-butyl dithiophosphate, wherein the mass ratio of butyl xanthate, pentyl xanthate, and di-n-butyl dithiophosphate is 0-200:0-200:4-40, and wherein the butyl xanthate and pentyl xanthate are not both 0.

[0015] Optionally, during the first roughing process, the dosage of the inhibitor is 50g-1500g per ton of feed, the dosage of the collector is 20-240g per ton of feed, and the dosage of the frother is 10-80g per ton of feed. And / or, during the second roughing process, the dosage of the combined modifier is 100-500g per ton of feed, the dosage of the inhibitor is 50g-1500g per ton of feed, the dosage of the combined collector is 20-240g per ton of feed, and the dosage of the frother is 10g-80g per ton of feed.

[0016] Optionally, the inhibitor may also be added during the first selection process; And / or, during the first sweep, the inhibitor, the collector, and the foaming agent are also added; And / or, during the second selection, the combined modifier and the inhibitor are also added; And / or, during the second sweep, the inhibitor, the combined collector, and the foaming agent are also added.

[0017] Optionally, during the first selection process, the amount of the inhibitor used is 20-500g per ton of ore feed; And / or, during the first scavenging, the amount of the inhibitor is 20-200g per ton of feed, the amount of the collector is 10-120g per ton of feed, and the amount of the frother is 4-40g per ton of feed. And / or, during the second selection, the dosage of the combined modifier is 50g-250g per ton of feed, and the dosage of the inhibitor is 35g per ton of feed; And / or, during the second scavenging, the dosage of the inhibitor is 20-200g per ton of feed, the dosage of the combined collector is 10-120g per ton of feed, and the dosage of the frother is 4-40g per ton of feed.

[0018] Compared with the prior art, the beneficial effects of this application include: The beneficiation method for recovering nickel from ultrabasic nickel tailings provided in this application solves the fundamental reason why coarse particles cannot be recovered by flotation by grinding coarse particles, solves the problem of fine gangue covering nickel minerals by adding a combination of modifiers, and enhances the recovery of fine-grained nickel minerals by adding a combination of collectors. This application divides the nickel lost in the tailings into two categories by "separate separation" and then takes corresponding measures for specific reasons for loss, thus achieving efficient and comprehensive utilization of strategic metal nickel resources. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation on the scope of this application.

[0020] Figure 1 This is a schematic flowchart of the beneficiation method for recovering nickel from ultrabasic nickel tailings provided in Example 1. Detailed Implementation

[0021] It is important to note that during the grinding process of ultrabasic nickel ore, due to the significant differences in hardness among different minerals, some soft minerals (such as talc, serpentine, and chlorite) are easily over-crushed, while some harder minerals (such as pyrrhotite and nickel-bearing pyrrhotite) are not fully liberated. Over-crushed gangue minerals can easily cover fine-grained pyrrhotite, causing it to be lost in the tailings. The coarse particles, due to insufficient liberation, higher specific gravity, and larger particle size, cannot be lifted to the upper layer by air bubbles and are thus lost in the tailings. Inevitably, some nickel in ultrabasic nickel ore is lost in both the coarse and fine-grained tailings, resulting in a "two-way loss" phenomenon.

[0022] Based on this, in order to solve the problem of large particle size distribution of ultrabasic nickel tailings caused by this phenomenon, this application proposes the following solution.

[0023] Furthermore, the solution provided in this application will be explained in more detail as follows: This application provides a mineral processing method for recovering nickel from ultrabasic nickel tailings, comprising: The flotation tailings of ultrabasic nickel rock are classified to obtain coarse-grained and fine-grained products. The coarse-grained product is ground to obtain a grinding slurry. The grinding slurry, inhibitor, collector and frother are mixed and subjected to a first roughing process to obtain a first roughing concentrate and a first roughing tailings. The first roughing concentrate is then subjected to a first cleaning process to obtain a first concentrate, and the first roughing tailings are subjected to a first scavenging process to obtain a first tailings. It is important to note that grinding reduces the particle size of coarse-grained products, increases the degree of liberation of individual particles, enables the nickel minerals associated with gangue to be liberated, and reduces the particle size of nickel minerals, allowing bubbles to lift the nickel minerals to the upper layer of the slurry for recovery. A combination of modifier, inhibitor, collector and frother are added sequentially to the fine-grained product for a second roughing process to obtain a second roughing tailings and a second roughing concentrate; the second roughing concentrate is then subjected to a second cleaning process to obtain a second concentrate, and the second roughing tailings are subjected to a second scavenging process to obtain a second tailings. The combined modifiers include sodium methylnaphthalene sulfonate formaldehyde condensate, sodium carbonate, and water glass; It is important to note that the sodium methylnaphthalene sulfonate formaldehyde condensate in the combined modifiers plays a significant role in dispersion and improves the fluidity of the slurry. Sodium carbonate, as a pH buffer, can adjust the slurry to a slightly alkaline state, which is beneficial for the dissolution of the inhibitor CMC. It also has a certain activating effect on sulfide ores (nickel pyrrhotite, nickel-bearing pyrrhotite, chalcopyrite, etc.). Water glass is a highly efficient silicate mineral inhibitor and can work synergistically with CMC to achieve a better inhibitory effect. Ultrabasic copper-nickel rocks contain large amounts of talc and serpentine. Talc has a Mohs hardness of 1 (the lowest among minerals), and serpentine has a Mohs hardness of 2.5-3.5. Both are extremely soft minerals and are prone to mud formation during grinding. Fine mud adheres to the surface of useful minerals, forming a cap that hinders collector adsorption, making floatable coarse particles difficult to float and reducing recovery rates. Therefore, it is necessary to add modifiers to disperse fine-grained minerals. In some embodiments, the pH value of the second coarse selection is 7.5-10; The combined collectors include xanthate collectors and di-n-butyldithiophosphate ammonium.

[0024] It should be noted that the di-n-butyl dithiophosphate in the combined collector has a good collecting effect on fine-grained sulfide minerals and works synergistically with xanthate collectors to effectively recover fine-grained nickel minerals.

[0025] In some embodiments, the particle size of the coarse-grained product is ≥0.1 mm; Optionally, the particle size of the coarse-grained product can be any value of 0.1 mm, 0.5 mm, 1 mm or ≥0.1 mm; The particle size of the fine-grained product is <0.1 mm; Optionally, the particle size of the fine-particle product can be any value of 0.01 mm, 0.05 mm, 0.099 mm or <0.1 mm; The fineness of the grinding slurry is -0.074 mm, accounting for 55%-80%.

[0026] Optionally, the fineness of the grinding slurry -0.074 mm can be any value between 55%, 60%, 65%, 70%, 75%, 80%, or 55-80%.

[0027] In some embodiments, the inhibitor comprises carboxymethyl cellulose; And / or, the collector includes xanthate; And / or, the foaming agent includes at least one of pine oil, No. 2 oil, and MIBC.

[0028] In some embodiments, the carboxymethyl cellulose has a molecular weight greater than 500,000 g / mol and a degree of substitution greater than 0.6.

[0029] Optionally, the molecular weight of carboxymethyl cellulose can be any value of 510,000 g / mol, 550,000 g / mol, 600,000 g / mol, 650,000 g / mol, 700,000 g / mol or greater than 500,000 g / mol, and the degree of substitution can be any value of 0.61, 0.65, 0.7, 0.75, 0.8 or greater than 0.6.

[0030] It is important to note that talc and some serpentine minerals have natural buoyancy. Carboxymethyl cellulose (CMC), as a gangue mineral inhibitor, is a highly effective inhibitor of these layered silicate gangue minerals. However, the inhibitory effect varies greatly depending on the molecular weight and degree of substitution of CMC. The molecular weight of CMC should be greater than 500,000 g / mol, and the degree of substitution should be greater than 0.6. Larger molecular weights have better steric hindrance effects, and higher substitution degrees can make the talc surface more hydrophilic. Only CMCs with these parameters can better exert their inhibitory effect on gangue minerals. Larger molecular weight CMCs can stably adsorb on the surface of gangue minerals such as talc and serpentine, and have better steric hindrance effects, resulting in better inhibitory effects. When the degree of substitution is greater than 0.6, CMC has better solubility and hydrophilicity, which is beneficial for the inhibition of gangue minerals.

[0031] In some embodiments, in the combined modifier, the mass ratio of the sodium methylnaphthalene sulfonate formaldehyde condensate, the sodium carbonate, and the water glass is 3-30:20-50:30-60.

[0032] Optionally, in the combined modifier, the mass ratio of sodium methylnaphthalenesulfonate formaldehyde condensate, sodium carbonate and water glass can be any value between (3:20:30), (10:20:30), (20:20:30), (30:20:30), (15:30:30), (15:50:60), (15:50:60) or 3-30:20-50:30-60.

[0033] In some embodiments, in the combined collector, the mass ratio of the xanthate collector to the di-n-butyl dithiophosphate ammonium is 20-200:4-40.

[0034] Optionally, in the combined collector, the mass ratio of xanthate collector to di-n-butyldithiophosphate ammonium can be any value between 20:4, 50:4, 100:4, 150:4, 200:4, 100:20, 100:40, 200:40, or 20-200:4-40.

[0035] In some embodiments, the combined collector comprises butyl xanthate, pentyl xanthate, and di-n-butyl dithiophosphate, wherein the mass ratio of the butyl xanthate, the pentyl xanthate, and the di-n-butyl dithiophosphate is 0-200:0-200:4-40, and wherein the butyl xanthate and the pentyl xanthate are not both 0.

[0036] Optionally, the mass ratio of butyl xanthate, pentyl xanthate, and di-n-butyldithiophosphate can be any value between 0:100:4, 100:0:4, 100:100:10, 200:200:40, or 0-200:0-200:4-40, wherein the butyl xanthate and the pentyl xanthate are not both 0.

[0037] In some embodiments, during the first roughing process, the dosage of the inhibitor is 50g-1500g per ton of feed, the dosage of the collector is 20-240g per ton of feed, and the dosage of the frother is 10-80g per ton of feed. Optionally, the dosage of the inhibitor can be 50 g per ton of feed, 100 g per ton of feed, 500 g per ton of feed, 1000 g per ton of feed, 1500 g per ton of feed, or any value between 50 and 1500 g per ton of feed; the dosage of the collector can be 20 g per ton of feed, 60 g per ton of feed, 100 g per ton of feed, 150 g per ton of feed, 200 g per ton of feed, 240 g per ton of feed, or any value between 20 and 240 g per ton of feed; and the dosage of the frother can be 10 g per ton of feed, 20 g per ton of feed, 40 g per ton of feed, 60 g per ton of feed, 80 g per ton of feed, or any value between 10 and 80 g per ton of feed. And / or, during the second roughing process, the combined modifier is used at a rate of 100-500g per ton of feed, the inhibitor at a rate of 50g-1500g per ton of feed, the combined collector at a rate of 20-240g per ton of feed, and the frother at a rate of 10g-80g per ton of feed.

[0038] Optionally, during the second roughing process, the dosage of the combined modifier can be 100 g / ton of feed, 200 g / ton of feed, 300 g / ton of feed, 400 g / ton of feed, 500 g / ton of feed, or any value between 100 and 500 g / ton of feed; the dosage of the depressant can be 50 g / ton of feed, 100 g / ton of feed, 500 g / ton of feed, 1000 g / ton of feed, 1500 g / ton of feed, or any value between 50 and 1500 g / ton of feed; the dosage of the combined collector can be 20 g / ton of feed, 50 g / ton of feed, 100 g / ton of feed, 150 g / ton of feed, 200 g / ton of feed, 240 g / ton of feed, or any value between 20 and 240 g / ton of feed; and the dosage of the frother can be 10 g / ton of feed, 2 ... g per ton of ore, 40 g per ton of ore, 60 g per ton of ore, 80 g per ton of ore, or any value between 10 and 80 g per ton of ore; In some embodiments, the inhibitor is also added during the first selection process; And / or, during the first sweep, the inhibitor, the collector, and the foaming agent are also added; And / or, during the second selection, the combined modifier and the inhibitor are also added; And / or, during the second sweep, the inhibitor, the combined collector, and the foaming agent are also added.

[0039] In some embodiments, when performing the first selection, the amount of the inhibitor used is 20-500g per ton of ore; Optionally, during the first selection, the amount of inhibitor can be 20 g per ton of feed, 100 g per ton of feed, 200 g per ton of feed, 300 g per ton of feed, 400 g per ton of feed, 500 g per ton of feed, or any value between 20 and 500 g per ton of feed. And / or, during the first scavenging, the amount of the inhibitor is 20-200g per ton of feed, the amount of the collector is 10-120g per ton of feed, and the amount of the frother is 4-40g per ton of feed. Optionally, during the first scavenging, the dosage of the inhibitor can be 20 g per ton of feed, 50 g per ton of feed, 100 g per ton of feed, 200 g per ton of feed, or any value between 20 and 200 g per ton of feed, and the dosage of the collector can be 4 g per ton of feed, 10 g per ton of feed, 20 g per ton of feed, 40 g per ton of feed, or any value between 4 and 40 g per ton of feed. And / or, during the second selection, the dosage of the combined modifier is 50g-250g per ton of feed, and the dosage of the inhibitor is 5-50g per ton of feed; Optionally, during the second selection, the amount of the combined modifier can be 50 g per ton of feed, 100 g per ton of feed, 150 g per ton of feed, 200 g per ton of feed, 250 g per ton of feed, or any value between 50 and 250 g per ton of feed. And / or, during the second scavenging, the dosage of the inhibitor is 20-100g per ton of feed, the dosage of the combined collector is 10-120g per ton of feed, and the dosage of the frother is 4-40g per ton of feed.

[0040] Optionally, during the second scavenging process, the dosage of the inhibitor can be any value between 20 g / ton of feed, 50 g / ton of feed, 100 g / ton of feed, or 20-100 g / ton of feed; the dosage of the combined collector can be any value between 10 g / ton of feed, 50 g / ton of feed, 100 g / ton of feed, 120 g / ton of feed, or 10-120 g / ton of feed; and the dosage of the frother can be any value between 4 g / ton of feed, 10 g / ton of feed, 20 g / ton of feed, 40 g / ton of feed, or 4-40 g / ton of feed.

[0041] The implementation schemes of this application will be described in detail below with reference to specific embodiments. However, those skilled in the art will understand that the following embodiments are only for illustrating this application and should not be regarded as limiting the scope of this application. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used without specified manufacturers are all conventional products that can be purchased commercially.

[0042] Example 1 This embodiment provides a mineral processing method for recovering nickel from ultrabasic nickel tailings. The flow chart of this mineral processing method is shown below. Figure 1 As shown, the ultrabasic rock nickel tailings originated from a nickel mine, and the specific steps are as follows: Step A1: The tailings slurry is classified using a spiral chute to obtain coarse-grained products and fine-grained products. The particle size of the coarse-grained products is ≥0.1mm, and the particle size of the fine-grained products is <0.1mm. Step A2: Grind the coarse-grained product to a fineness of -0.074mm, accounting for 65%, to obtain a grinding slurry; Step A3: Add 200g of CMC per ton of feed (unless otherwise specified, the unit of reagent dosage in this application is g per ton of feed), 120g of butyl xanthate per ton of feed, and 30g of frother pine oil per ton of feed to the grinding slurry for one roughing process to obtain roughing concentrate and roughing tailings. Step A4: Add 30g of CMC per ton of feed to the rough concentrate for one cleaning process to obtain a first-clean concentrate. Add 20g of CMC per ton of feed to the first-clean concentrate for a second cleaning process to obtain a second-clean concentrate. Add 10g of CMC per ton of feed to the second-clean concentrate for a third cleaning process to obtain the first concentrate. Step A5: Add 50g of CMC, 50g of butyl xanthate, and 10g of pine oil to the roughing tailings for one scavenging. Add 30g of butyl xanthate to the tailings from the first scavenging and perform a second scavenging to obtain the first tailings. In process A6, 200g of a combined modifier (sodium methylnaphthalene sulfonate formaldehyde condensate, sodium carbonate and water glass in a mass ratio of 20:30:50) is added per ton of feed to the fine-grained product. Then, 300g / t of CMC, 150g / t of a combined collector (butyl xanthate and di-n-butyl dithiophosphate in a mass ratio of 8:2) and 10g / t of pine oil frother are added per ton of feed for a roughing process. The pH value of this roughing process is 9.5, resulting in a roughing concentrate and a roughing tailings. Step A7: Add 50g of combined modifier per ton of feed to the rough concentrate and 20g of CMC per ton of feed for one cleaning process to obtain a first-clean concentrate. Add 10g of CMC per ton of feed to the first-clean concentrate for a second cleaning process to obtain a second-clean concentrate. Add 5g of CMC per ton of feed to the second-clean concentrate for a third cleaning process to obtain a second concentrate. In step A8, 100g of CMC, 80g of combined collector, and 5g of pine oil are added to the roughing tailings for a first scavenging process. The tailings from the first scavenging process are then scavenged again with 40g of combined collector added to the tailings to obtain the second tailings.

[0043] In this embodiment, the carboxymethyl cellulose (CMC) has a molecular weight greater than 500,000 g / mol and a degree of substitution greater than 0.6.

[0044] All intermediate mines use a sequential return method to enter the previous operation.

[0045] The products of the method were tested, and the specific results are shown in Table 1.

[0046] Table 1 Results of the Test

[0047] Example 2 This embodiment provides a mineral processing method for recovering nickel from ultrabasic nickel tailings, which originate from a nickel mine in Sichuan Province. The specific steps are as follows: Step A1: Use a hydrocyclone to classify the tailings slurry to obtain coarse-grained products and fine-grained products. The particle size of the coarse-grained products is ≥0.1mm, and the particle size of the fine-grained products is <0.1mm. Step A2: Grind the coarse-grained product to a fineness of -0.074mm, accounting for 70%, to obtain a grinding slurry; Step A3: Add 150g of CMC per ton of feed, 100g of butyl xanthate per ton of feed, and 40g of frother No. 2 oil per ton of feed to the grinding slurry in sequence for one roughing process to obtain roughing concentrate and roughing tailings. Step A4: Add 60g of CMC per ton of feed to the rough concentrate for one cleaning process to obtain a first-clean concentrate. Add 30g of CMC per ton of feed to the first-clean concentrate for a second cleaning process to obtain a second-clean concentrate. Add 20g of CMC per ton of feed to the second-clean concentrate for a third cleaning process to obtain the first concentrate. Step A5: Add 40g of CMC, 50g of butyl xanthate, and 15g of No. 2 oil to the roughing tailings for one scavenging. Add 20g of butyl xanthate to the tailings from the first scavenging for a second scavenging to obtain the first tailings. In process A6, 180g of a combined modifier (sodium methylnaphthalene sulfonate formaldehyde condensate: sodium carbonate: water glass in a mass ratio of 10:40:50) is added per ton of feed to the fine-grained product. Then, 200g of CMC is added per ton of feed, 150g of a combined collector (isoamyl xanthate: di-n-butyl dithiophosphate ammonium in a mass ratio of 9:1) is added per ton of feed, and 15g of frother No. 2 oil is added per ton of feed for one roughing process to obtain roughing concentrate and roughing tailings. Step A7: Add 90g of combined modifier per ton of feed to the rough concentrate and 30g of CMC per ton of feed for one cleaning process to obtain a first-clean concentrate. Add 20g of CMC per ton of feed to the first-clean concentrate for a second cleaning process to obtain a second-clean concentrate. Add 10g of CMC per ton of feed to the second-clean concentrate for a third cleaning process to obtain a second concentrate. In process A8, 50g of CMC, 60g of combined collector, and 5g of No. 2 oil are added to the roughing tailings for a first scavenging process. The tailings from the first scavenging process are then scavenged again with 30g of combined collector added to the tailings for a second scavenging process to obtain the second tailings.

[0048] All intermediate mines use a sequential return method to enter the previous operation.

[0049] The products of the method were tested, and the specific results are shown in Table 2.

[0050] Table 2 Results Test

[0051] Example 3 This embodiment provides a mineral processing method for recovering nickel from ultrabasic nickel tailings, which originate from a nickel mine in Guangxi. The specific steps are as follows: Step A1: Use a hydrocyclone to classify the tailings slurry to obtain coarse-grained products and fine-grained products. The particle size of the coarse-grained products is ≥0.1mm, and the particle size of the fine-grained products is <0.1mm. Step A2: Grind the coarse-grained product to a fineness of -0.074mm, accounting for 70%, to obtain a grinding slurry; Step A3: Add 300g of CMC per ton of feed, 120g of butyl xanthate per ton of feed, and 50g of frother No. 2 oil per ton of feed to the grinding slurry in sequence for one roughing process to obtain roughing concentrate and roughing tailings. Step A4: Add 80g of CMC per ton of feed to the rough concentrate for one cleaning process to obtain a first-clean concentrate. Add 30g of CMC per ton of feed to the first-clean concentrate for a second cleaning process to obtain a second-clean concentrate. Add 20g of CMC per ton of feed to the second-clean concentrate for a third cleaning process to obtain the first concentrate. Step A5: Add 60g of CMC per ton of feed, 40g of butyl xanthate per ton of feed, and 20g of No. 2 oil per ton of feed to the roughing tailings for one scavenging. Add 20g of butyl xanthate per ton of feed to the tailings from the first scavenging and perform a second scavenging to obtain the first tailings. In process A6, 150g of a combined modifier (sodium methylnaphthalene sulfonate formaldehyde condensate: sodium carbonate: water glass in a mass ratio of 20:40:40) is added per ton of feed to the fine-grained product. Then, 300g of CMC is added per ton of feed, 150g of a combined collector (butyl xanthate: isopentyl xanthate: di-n-butyl dithiophosphate ammonium in a mass ratio of 4:5:1) is added per ton of feed, and 40g of No. 2 frother is added per ton of feed for roughing to obtain rough concentrate and rough tailings. Step A7: Add 60g of combined modifier per ton of feed to the rough concentrate and 50g of CMC per ton of feed for one cleaning process to obtain a first-clean concentrate. Add 30g of CMC per ton of feed to the first-clean concentrate for a second cleaning process to obtain a second-clean concentrate. Add 20g of CMC per ton of feed to the second-clean concentrate for a third cleaning process to obtain a second concentrate. In process A8, 80g of CMC, 50g of combined collector, and 10g of No. 2 oil are added to the roughing tailings for a first scavenging process. The tailings from the first scavenging process are then scavenged again with 20g of combined collector added to the tailings for a second scavenging process to obtain the second tailings.

[0052] All intermediate mines use a sequential return method to enter the previous operation.

[0053] The results of the examples show that 38.27% of the nickel metal in the tailings was recovered and reused.

[0054] The products of the method were tested, and the specific results are shown in Table 3.

[0055] Table 3 Results of the Test

[0056] Comparative Example 1 The difference from Example 1 is that the classification process of step A1 is not performed. Instead, the tailings slurry is processed according to the flotation steps of the coarse-grained product, that is, the tailings slurry is processed in steps A2-5.

[0057] The products of the method were tested, and the specific results are shown in Table 4.

[0058] Table 4 Results Test

[0059] The experimental results show that without classification, a large amount of fine gangue minerals adhere to the surface of useful minerals, hindering the adsorption of collectors, making floatable coarse particles difficult to float and reducing the recovery rate. In addition, fine mud is easily carried away by foam machinery and enters the concentrate, resulting in low concentrate grade, high impurities, and the inability to form a marketable product.

[0060] Comparative Example 2 The difference from Example 1 is that no combination modifier is added in steps A6-7.

[0061] The products of the method were tested, and the specific results are shown in Table 5.

[0062] Table 5 Results of the Test

[0063] The experimental results show that, without the addition of combined modifiers during fine-grained flotation, fine gangue minerals adhere to the surface of useful minerals, hindering collector adsorption, making floatable coarse particles difficult to float, and reducing recovery rate. Furthermore, fine mud is easily entrained by froth machinery and enters the concentrate, resulting in low concentrate grade and high impurities, making it impossible to form a marketable product from the secondary concentrate.

[0064] Comparative Example 3 The difference from Example 1 is that the combination modifier is replaced with an equal mass of sodium methylnaphthalenesulfonate formaldehyde condensate.

[0065] The products of the method were tested, and the specific results are shown in Table 6.

[0066] Table 6 Results of the Test

[0067] Experimental results show that using sodium methylnaphthalenesulfonate formaldehyde condensate alone as a modifier is far less effective than using a combination of inhibitors. Without the addition of sodium carbonate and water glass, the gangue minerals exhibit weaker positive charge, resulting in poorer dispersion.

[0068] Comparative Example 4 The difference from Example 1 is that the combined modifier is replaced with an equal mass of water glass.

[0069] The products of the method were tested, and the specific results are shown in Table 7.

[0070] Table 7 Results of the Test

[0071] Experimental results show that using water glass alone as an inhibitor is less effective than using a combination of inhibitors. Water glass only hydrolyzes in the slurry to form silica colloids (H2SiO3) and HSiO3. - SiO3 2- It adsorbs with positively charged gangue minerals, but fails to form sulfonic acid groups (-SO3) with sodium methylnaphthalenesulfonate formaldehyde condensate. - The synergistic effect is enhanced, but the decentralized effect is diminished.

[0072] Comparative Example 5 The difference from Example 1 is that the combined modifier is replaced with an equal mass of sodium carbonate.

[0073] The products of the method were tested, and the specific results are shown in Table 8.

[0074] Table 8 Results of the Test

[0075] Experimental results show that using sodium carbonate alone as a modifier does not produce silica colloids (H2SiO3) or HSiO3. - SiO3 2- sulfonic acid group (-SO3) - It adsorbs with positively charged gangue minerals, resulting in poor dispersion.

[0076] Comparative Example 6 The difference from Example 1 is that the combined modifier is replaced with sodium methylnaphthalenesulfonate formaldehyde condensate and sodium carbonate in a mass ratio of 20:30, that is, water glass is not added.

[0077] The products of the method were tested, and the specific results are shown in Table 9.

[0078] Table 9 Results of the Test

[0079] Experimental results show that the lack of silica colloids (H2SiO3) and HSiO3 produced by the hydrolysis of water glass is detrimental. - SiO3 2- The sulfonic acid group (-SO3) formed by the condensation of sodium methylnaphthalenesulfonate with formaldehyde - The synergistic effect is reduced, and water glass, being an alkaline substance, can further adjust the pH value of the slurry, which is beneficial to increasing the positive charge of gangue minerals and improving the dispersion effect.

[0080] Comparative Example 7 The difference from Example 1 is that the combined modifier is replaced with sodium carbonate and water glass in a mass ratio of 30:50, that is, sodium methylnaphthalene sulfonate formaldehyde condensate is not added.

[0081] The products of the method were tested, and the specific results are shown in Table 10.

[0082] Table 10 Results Test

[0083] Experimental results show that the absence of the sulfonic acid group (-SO3) in sodium methylnaphthalenesulfonate formaldehyde condensate leads to the formation of sulfonic acid groups. - The silica colloids (H2SiO3) and HSiO3 produced by the hydrolysis of water glass - SiO 23 2- Synergistic effects are enhanced, while decentralized effects are diminished.

[0084] Comparative Example 8 The difference from Example 1 is that the combined collector is replaced with an equal mass of butyl xanthate, that is, di-n-butyl dithiophosphate ammonium is not added.

[0085] The products of the method were tested, and the specific results are shown in Table 11.

[0086] Table 11 Results of the Test

[0087] The experimental results show that when butyl xanthate is used as a single collector, the concentrate yield and recovery rate decrease significantly due to the lack of collection of fine particles and weakly oxidized nickel pyrite on the surface.

[0088] Comparative Example 9 The difference from Example 1 is that the combined collector is replaced with an equal mass of di-n-butyl dithiophosphate ammonium, that is, butyl xanthate is not added.

[0089] The products of the method were tested, and the specific results are shown in Table 12.

[0090] Table 12 Results Test

[0091] Note: The nickel grade of the feed used in Example 1 was 0.28%, which was the first batch of ultrabasic rock nickel tailings. The sample had been used up due to preliminary basic experimental research. Subsequent comparative examples were resampled, and the nickel grade of the second batch of ultrabasic rock nickel tailings was 0.31%. The following two points need to be explained: 1. The increase in tailings grade from 0.28% to 0.31% is a normal fluctuation in the production process, and such fluctuations are unavoidable; 2. The change in feed grade does not hinder the experimental research. The experimental results presented in Comparative Examples 2-9 still fully demonstrate the changes in relevant indicators caused by the adjustment of the combined collector and combined modifier.

[0092] The experimental results show that when di-n-butyl dithiophosphate ammonium is used as a single collector, the grade of the second concentrate is significantly reduced. Due to the lack of small molecular weight, fast-diffusion xanthate to work synergistically with di-n-butyl dithiophosphate ammonium, some nickel pyrite could not be effectively recovered.

[0093] analyze: As can be seen from the embodiments, the present application can effectively recover nickel minerals from ultrabasic nickel tailings, greatly improving the comprehensive utilization rate of scarce strategic metal nickel resources, and providing resource security for many industries such as new energy, stainless steel, multi-metal alloys, electroplating, and magnetic materials.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0095] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, any of the claimed embodiments can be used in any combination. The information disclosed in this background section is intended only to enhance the understanding of the general background of this application and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

Claims

1. A beneficiation method for recovering nickel from ultrabasic nickel tailings, characterized in that, include: The flotation tailings of ultrabasic nickel rock are classified to obtain coarse-grained and fine-grained products. The coarse-grained product is ground to obtain a grinding slurry. The grinding slurry, inhibitor, collector and frother are mixed and subjected to a first roughing process to obtain a first roughing concentrate and a first roughing tailings. The first roughing concentrate is then subjected to a first cleaning process to obtain a first concentrate, and the first roughing tailings are subjected to a first scavenging process to obtain a first tailings. A combination of modifier, inhibitor, collector and frother are added sequentially to the fine-grained product for a second roughing process to obtain a second roughing tailings and a second roughing concentrate; the second roughing concentrate is then subjected to a second cleaning process to obtain a second concentrate, and the second roughing tailings are subjected to a second scavenging process to obtain a second tailings. The combined modifiers include sodium methylnaphthalene sulfonate formaldehyde condensate, sodium carbonate, and water glass; The combined collectors include xanthate collectors and di-n-butyldithiophosphate ammonium.

2. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 1, characterized in that, The coarse-grained product has a particle size ≥ 0.1 mm; The particle size of the fine-grained product is <0.1 mm; The fineness of the grinding slurry is -0.074 mm, accounting for 55%-80%.

3. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 1, characterized in that, The inhibitor includes carboxymethyl cellulose; And / or, the collector includes xanthate; And / or, the foaming agent includes at least one of pine oil, No. 2 oil, and MIBC.

4. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 3, characterized in that, The carboxymethyl cellulose has a molecular weight greater than 500,000 g / mol and a degree of substitution greater than 0.

6.

5. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 1, characterized in that, In the combined modifier, the mass ratio of the sodium methylnaphthalene sulfonate formaldehyde condensate, the sodium carbonate, and the water glass is 3-30:20-50:30-60.

6. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 1, characterized in that, In the combined collector, the mass ratio of the xanthate collector to the di-n-butyldithiophosphate ammonium is 20-200:4-40.

7. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 6, characterized in that, The combined collector comprises butyl xanthate, pentyl xanthate, and di-n-butyl dithiophosphate ammonium, wherein the mass ratio of butyl xanthate, pentyl xanthate, and di-n-butyl dithiophosphate ammonium is 0-200:0-200:4-40, and wherein the butyl xanthate and pentyl xanthate are not both 0.

8. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 1, characterized in that, During the first roughing process, the dosage of the inhibitor is 50g-1500g per ton of feed, the dosage of the collector is 20-240g per ton of feed, and the dosage of the frother is 10g-80g per ton of feed. And / or, during the second roughing process, the combined modifier is used at a rate of 100g-500g per ton of feed, the inhibitor is used at a rate of 50g-1500g per ton of feed, the combined collector is used at a rate of 20g-240g per ton of feed, and the frother is used at a rate of 10g-80g per ton of feed.

9. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 1, characterized in that, During the first selection process, the inhibitor is also added; And / or, during the first sweep, the inhibitor, the collector, and the foaming agent are also added; And / or, during the second selection, the combined modifier and the inhibitor are also added; And / or, during the second sweep, the inhibitor, the combined collector, and the foaming agent are also added.

10. The beneficiation method for recovering nickel from ultrabasic nickel tailings according to claim 9, characterized in that, During the first selection process, the amount of the inhibitor used is 20g-500g per ton of ore feed; And / or, during the first scavenging, the amount of the inhibitor is 20g-200g per ton of feed, the amount of the collector is 10g-120g per ton of feed, and the amount of the frother is 4g-40g per ton of feed. And / or, during the second selection, the dosage of the combined modifier is 50g-250g per ton of feed, and the dosage of the inhibitor is 35g per ton of feed; And / or, during the second scavenging, the dosage of the inhibitor is 20g-200g per ton of feed, the dosage of the combined collector is 10g-120g per ton of feed, and the dosage of the frother is 4g-40g per ton of feed.

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