A method for beneficiating high-magnesium low-grade copper-nickel sulfide ore

Abstract

The invention discloses a beneficiation method for high-magnesium low-grade copper-nickel sulfide ore, which adopts three-stage grinding, reduces the crushing stage, and the grinding particle size is relatively concentrated, which can fine-grind fine-grained materials while reducing over-grinding, so that fine-grained nickel-copper sulfide can be effectively dissociated, and the problem that the coarse particle size is too coarse to fully dissociate useful minerals and the fine particle size is seriously over-grinded in the traditional ball milling is solved, and the recovery rate of nickel-copper metal and the nickel-copper grade of the concentrate are improved. At the same time, a hydrocyclone is used to classify the grinding discharge for multiple times, and the composite force field of gravity and centrifugal force is used to separate fine mud and sediment products, and flotation is performed separately, which reduces the adsorption cover of fine mud materials in the ore pulp on useful metal minerals, increases the contact area between metal minerals and flotation reagents, and thus improves the recovery rate of nickel-copper sulfide.

Description

Technical Field

[0001] The invention relates to the technical field of copper-nickel sulfide ore dressing, and in particular to a method for dressing high-magnesium low-grade copper-nickel sulfide ore. Background Art

[0002] Nickel metal has good magnetism, plasticity and corrosion resistance, and is widely used in steel, nickel-based alloys, electroplating, batteries and other fields. The main raw material for extracting nickel metal in my country is copper-nickel sulfide ore. However, with the continuous development of mineral resources, the copper-nickel grade of copper-nickel sulfide ore has gradually decreased, making low-grade copper-nickel sulfide ore the main raw material for nickel metal extraction. For high-magnesium low-grade copper-nickel sulfide ore, nickel-copper sulfide minerals are mostly distributed in the ore in a star-shaped structure, and the useful metal minerals are embedded in a small particle size. If the traditional beneficiation method is used for sorting, it is very easy to have coarse particles that fail to dissociate effective minerals and fine particles that are seriously over-grinded during ball milling. It is difficult to effectively select the current high-magnesium low-grade copper-nickel sulfide ore. The general nickel recovery rate is between 55% and 65%, and the fine mud material in the slurry will adsorb and cover the useful metals, which increases the difficulty of metal mineral recovery, resulting in a low recovery rate of nickel-copper metals, resulting in a serious waste of low-grade copper-nickel sulfide ore resources. Therefore, the development of beneficiation methods for high-magnesium and low-grade copper-nickel sulfide ores is of great significance to improving the utilization rate of mineral resources and promoting the sustainable development of mineral resources. Summary of the invention

[0003] The present invention provides a beneficiation method for high-magnesium low-grade copper-nickel sulfide ore, aiming to solve the problem that the existing beneficiation method is difficult to effectively beneficiate the current high-magnesium low-grade copper-nickel sulfide ore, resulting in low utilization rate of mineral resources.

[0004] The present invention is a method for beneficiating a high-magnesium low-grade copper-nickel sulfide ore, comprising the following steps:

[0005] Step 1: Crushing, grinding and classification. The raw ore is coarsely crushed and then semi-autogenous milled. The ore pulp discharged from the semi-autogenous mill is screened, and the ore on the screen is returned to the semi-autogenous mill. The ore under the screen enters the ball mill. During ball milling, carbonate is added to adjust the pH value of the ore pulp to 8.5-9.5; the ball mill discharge enters the first hydrocyclone for primary classification, and the coarse-grained grit product of the primary classification enters the Isa mill for fine grinding. The fine-grained overflow product of the primary classification and the Isa mill discharge enter the second hydrocyclone for secondary classification. The secondary classification obtains the coarse-grained grit product and the fine-grained overflow product;

[0006] Step 2: Stirring the fine-grained overflow product obtained by secondary classification in step 1, adding inhibitors, collectors and auxiliary collectors during stirring, performing a flotation roughing, producing a roughing concentrate and a roughing tailing, and performing two scavenging of the roughing tailing to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailing;

[0007] Step 3: Stirring the coarse-grained sand product obtained by secondary classification in step 1, adding a collector and an auxiliary collector during stirring, and performing a flotation roughing to produce a roughing concentrate and a roughing tailing;

[0008] Step 4: Feed the roughing tailings in step 3 into the third hydrocyclone for three-stage classification, ball mill the coarse-grained sand settling products obtained by the three-stage classification, and return the ball mill discharge to the third hydrocyclone for classification circulation; stir the fine-grained overflow products obtained by the three-stage classification, add collectors and auxiliary collectors during stirring, and then perform two scavengings to produce primary scavenged concentrates, secondary scavenged concentrates and final tailings;

[0009] Step 5: The rougher concentrate obtained in step 2 and step 3 is subjected to two rounds of concentration to produce high-grade concentrate, primary concentrated tailings and secondary concentrated tailings;

[0010] Step 6: The scavenging concentrate, tailings and concentrating tailings obtained in steps 2, 4 and 5 are mixed and concentrating is performed twice to produce low-grade concentrate, primary concentrating tailings and secondary concentrating tailings. The secondary concentrating tailings are returned to the third hydrocyclone in step 4 for classification circulation.

[0011] Preferably, the amount of carbonate added in step 1 is 0-3 kg / t.

[0012] Preferably, the inhibitor is carboxymethyl cellulose, the collector is xanthate, and the auxiliary collector is black medicine.

[0013] Preferably, the added amount of the inhibitor is 0-500 g / t; the added amount of the collector is 100-400 g / t, and the added amount of the auxiliary collector is 50-100 g / t.

[0014] Preferably, the particle size of the ball mill feed in step 1 is -18mm, and the grinding concentration is 50%-70%.

[0015] Preferably, in step 1, the overflow product with a particle size less than 280 mesh in the second hydrocyclone accounts for more than 90%, and the concentration is 20%-40%.

[0016] Preferably, in step 4, the content of the overflow product with a particle size less than 200 mesh in the third hydrocyclone accounts for more than 90%, and the concentration is 20%-40%.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention provides a beneficiation method for high-magnesium low-grade copper-nickel sulfide ore, which adopts three-stage grinding. The first stage grinding adopts semi-autogenous grinding, which can reduce the crushing stage and the energy consumption of crushing and coarse grinding. The second stage grinding adopts ball milling, and the third stage grinding adopts Isa milling. Isa milling has a self-grading function, and the grinding particle size is relatively concentrated, which can reduce over-grinding while fine-grained materials are finely ground, so that fine-grained nickel-copper sulfide can be effectively dissociated, and the problem of coarse particle size failing to fully dissociate useful minerals and serious over-grinding of fine particle size in traditional ball milling is solved, and the recovery rate of nickel-copper metal and the nickel-copper grade of concentrate are improved. Then, a hydrocyclone is used to classify the grinding discharge for multiple times, and the composite force field of gravity and centrifugal force is used to separate fine mud and sediment products, and flotation is performed separately, which reduces the adsorption cover of fine mud materials in the slurry on useful metal minerals, increases the contact area between metal minerals and flotation reagents, and thus improves the recovery rate of nickel-copper sulfide.

[0019] 2. The present invention provides a beneficiation method for high-magnesium low-grade copper-nickel sulfide ore. When sorting fine-grained slurry, a magnesium-containing mineral inhibitor is added to inhibit the floating of the magnesium-containing mineral. At the same time, a collector and an auxiliary collector are added. The collector acts on the surface of the target mineral to repel water. After the slurry is aerated, foam is generated and adsorbed on the foaming surface. The auxiliary collector stabilizes the foam and is not easy to break. The foam is then scraped out with the foam to form a concentrate. This method greatly improves the recovery rate of nickel-copper metals and the nickel-copper grade of the concentrate, reduces the magnesium content in the concentrate, and achieves the purpose of effectively selecting high-magnesium low-grade copper-nickel sulfide ore.

[0020] 3. The present invention provides a beneficiation method for high-magnesium low-grade copper-nickel sulfide ore, wherein the roughing tailings are further ball-milled to further separate the minerals that cannot be dissociated into monomers for flotation recovery, thereby achieving the purpose of increasing the recovery rate of nickel-copper minerals and improving the utilization rate of mineral resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The figure is a process flow chart of the mineral processing method of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0023] Example 1

[0024] like Figure 1 As shown, a certain high-magnesium low-grade copper-nickel sulfide ore with nickel and copper grades of 0.45% and 0.25% respectively is beneficiated using the beneficiation method steps of the present invention:

[0025] Step 1: crushing, grinding and classification. The ore with a particle size of 0-300mm after coarse crushing of the original ore is semi-autogenous grinding. The ore pulp discharged from the semi-autogenous grinding is screened with a screen with a particle size of 18mm. The ore on the screen is returned to the semi-autogenous grinding mill, and the ore under the screen enters the ball mill. The ball mill feed particle size is -18mm, and the grinding concentration is 50%. During ball milling, 1kg / t sodium carbonate is added to adjust the pulp pH value to 8.5; the ball mill discharge enters the first hydrocyclone for primary classification, and the coarse-grained grit product of the primary classification enters the Isa mill for fine grinding. The fine-grained overflow product of the primary classification and the Isa mill discharge enter the second hydrocyclone for secondary classification. The secondary classification obtains the coarse-grained grit product and the fine-grained overflow product. The overflow product with a particle size less than 280 mesh accounts for 90% and the concentration is 20%;

[0026] Step 2: feeding the fine-grained overflow product obtained from the secondary classification in step 1 into a mixing barrel, adding 100 g / t of carboxymethyl cellulose to the mixing barrel to inhibit fine-grained magnesium-containing gangue minerals, and adding 100 g / t of ethyl xanthate and 50 g / t of butyl ammonium black medicine, performing a flotation roughing, producing a roughing concentrate and a roughing tailing, and the roughing tailing is subjected to two scavengings to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailing;

[0027] Step 3: feeding the coarse-grained sand product obtained by secondary classification in step 1 into a mixing barrel, adding 100 g / t ethyl xanthate and 50 g / t butyl ammonium black medicine into the mixing barrel, and performing a flotation roughing to produce a roughing concentrate and a roughing tailing;

[0028] Step 4: Feed the roughing tailings in step 3 into the third hydrocyclone for three-stage classification, ball mill the coarse-grained sand product obtained by the three-stage classification, and return the ball-milled ore to the third hydrocyclone for classification circulation; the fine-grained overflow product with a particle size of less than 200 mesh, a content of 90%, and a concentration of 20% obtained by the three-stage classification is sent to a mixing barrel, 100g / t of ethyl xanthate and 50g / t of butyl ammonium black medicine are added to the mixing barrel, and then two scavengings are performed to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailings;

[0029] Step 5: The rougher concentrate obtained in step 2 and step 3 is subjected to two rounds of concentration to produce high-grade concentrate, primary concentrated tailings and secondary concentrated tailings;

[0030] Step 6: The scavenging concentrate, tailings and concentrating tailings obtained in steps 2, 4 and 5 are mixed and concentrating is performed twice to produce low-grade concentrate, primary concentrating tailings and secondary concentrating tailings. The secondary concentrating tailings are returned to the third hydrocyclone in step 4 for classification circulation.

[0031] Through the above beneficiation steps, the lean ore with nickel and copper grades of 0.45% and 0.25% were separated, and the nickel and copper grades of concentrate and tailings products were detected by ICP inductively coupled ion emission spectrometer. The nickel and copper grades of high-grade concentrate were 4.75% and 2.10%, and those of low-grade concentrate were 2.05% and 1.43%, respectively. The total nickel and copper recoveries were 72.20% and 59.54%, respectively.

[0032] Example 2

[0033] like Figure 1 As shown, a high-magnesium low-grade copper-nickel sulfide ore with nickel and copper grades of 0.55% and 0.33% respectively is beneficiated using the beneficiation method steps of the present invention:

[0034] Step 1: Crushing, grinding and classification. The ore with a particle size of 0-300mm after coarse crushing of the original ore is semi-autogenous grinding. The ore pulp discharged from the semi-autogenous grinding is screened with a screen with a particle size of 18mm. The ore on the screen is returned to the semi-autogenous grinding mill, and the ore under the screen enters the ball mill. The ball mill feed particle size is -18mm, and the grinding concentration is 60%. During ball milling, 2kg / t sodium carbonate is added to adjust the pulp pH value to 9.0; the ball mill discharge enters the first hydrocyclone for primary classification, and the coarse-grained grit product of the primary classification enters the Isa mill for fine grinding. The fine-grained overflow product of the primary classification and the Isa mill discharge enter the second hydrocyclone for secondary classification. The secondary classification obtains the coarse-grained grit product and the fine-grained overflow product. The overflow product with a particle size less than 280 mesh accounts for 92% and the concentration is 30%;

[0035] Step 2: The fine-grained overflow product obtained from the secondary classification in step 1 is fed into a mixing barrel, 200 g / t of carboxymethyl cellulose is added to the mixing barrel to inhibit fine-grained magnesium-containing gangue minerals, and 150 g / t of ethyl xanthate and 80 g / t of butyl ammonium black powder are added at the same time, and a flotation roughing is performed to produce a roughing concentrate and a roughing tailing. The roughing tailing is scavenged twice to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailing;

[0036] Step 3: The coarse-grained sand product obtained by secondary classification in step 1 is fed into a mixing barrel, 150 g / t of ethyl xanthate and 80 g / t of butyl ammonium black medicine are added to the mixing barrel, and a flotation roughing is performed to produce a roughing concentrate and a roughing tailing;

[0037] Step 4: Feed the roughing tailings in step 3 into the third hydrocyclone for three-stage classification, ball mill the coarse-grained sand product obtained by the three-stage classification, and return the ball-milled ore to the third hydrocyclone for classification circulation; send the fine-grained overflow product with a particle size of less than 200 mesh, a content of 92%, and a concentration of 30% obtained by the three-stage classification into a mixing barrel, add 100g / t ethyl xanthate and 50g / t butyl ammonium black medicine into the mixing barrel, and then perform two scavengings to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailings;

[0038] Step 5: The rougher concentrate obtained in step 2 and step 3 is subjected to two rounds of concentration to produce high-grade concentrate, primary concentrated tailings and secondary concentrated tailings;

[0039] Step 6: The scavenging concentrate, tailings and concentrating tailings obtained in steps 2, 4 and 5 are mixed and concentrating is performed twice to produce low-grade concentrate, primary concentrating tailings and secondary concentrating tailings. The secondary concentrating tailings are returned to the third hydrocyclone in step 4 for classification circulation.

[0040] Through the above beneficiation steps, the lean ore with nickel and copper grades of 0.55% and 0.33% were separated, and the nickel and copper grades of concentrate and tailings products were detected by ICP inductively coupled ion emission spectrometer. The nickel and copper grades of high-grade concentrate were 4.38% and 3.13%, respectively, and the nickel and copper grades of low-grade concentrate were 0.94% and 0.61%, respectively. The total nickel and copper recoveries were 74.31% and 88.30%, respectively.

[0041] Example 3

[0042] like Figure 1 As shown, a high-magnesium low-grade copper-nickel sulfide ore with nickel and copper grades of 0.47% and 0.23% respectively is beneficiated using the beneficiation method steps of the present invention:

[0043] Step 1: Crushing, grinding and classification. The ore with a particle size of 0-300mm after coarse crushing of the original ore is semi-autogenous grinding. The ore pulp discharged from the semi-autogenous grinding is screened with a screen with a particle size of 18mm. The ore on the screen is returned to the semi-autogenous grinding mill, and the ore under the screen enters the ball mill. The ball mill feed particle size is -18mm, and the grinding concentration is 70%. During ball milling, 3kg / t sodium carbonate is added to adjust the pulp pH value to 9.5; the ball mill discharge enters the first hydrocyclone for primary classification, and the coarse-grained grit product of the primary classification enters the Isa mill for fine grinding. The fine-grained overflow product of the primary classification and the Isa mill discharge enter the second hydrocyclone for secondary classification. The secondary classification obtains the coarse-grained grit product and the fine-grained overflow product. The overflow product with a particle size less than 280 mesh accounts for 95% and the concentration is 40%;

[0044] Step 2: The fine-grained overflow product obtained from the secondary classification in step 1 is fed into a mixing barrel, 300 g / t of carboxymethyl cellulose is added to the mixing barrel to inhibit fine-grained magnesium-containing gangue minerals, and 100 g / t of ethyl xanthate and 50 g / t of butyl ammonium black medicine are added at the same time, and a flotation roughing is performed to produce a roughing concentrate and a roughing tailing. The roughing tailing is scavenged twice to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailing;

[0045] Step 3: feeding the coarse-grained sand product obtained by secondary classification in step 1 into a mixing barrel, adding 100 g / t ethyl xanthate and 50 g / t butyl ammonium black medicine into the mixing barrel, and performing a flotation roughing to produce a roughing concentrate and a roughing tailing;

[0046] Step 4: Feed the roughing tailings in step 3 into the third hydrocyclone for three-stage classification, ball mill the coarse-grained sand product obtained by the three-stage classification, and return the ball-milled ore to the third hydrocyclone for classification circulation; send the fine-grained overflow product with a particle size of less than 200 mesh, a content of 95%, and a concentration of 40% obtained by the three-stage classification into a mixing barrel, add 100g / t ethyl xanthate and 50g / t butyl ammonium black medicine into the mixing barrel, and then perform two scavengings to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailings;

[0047] Step 5: The rougher concentrate obtained in step 2 and step 3 is subjected to two rounds of concentration to produce high-grade concentrate, primary concentrated tailings and secondary concentrated tailings;

[0048] Step 6: The scavenging concentrate, tailings and concentrating tailings obtained in steps 2, 4 and 5 are mixed and concentrating is performed twice to produce low-grade concentrate, primary concentrating tailings and secondary concentrating tailings. The secondary concentrating tailings are returned to the third hydrocyclone in step 4 for classification circulation.

[0049] Through the above beneficiation steps, the lean ore with nickel and copper grades of 0.47% and 0.23% were separated, and the nickel and copper grades of concentrate and tailings products were detected by ICP inductively coupled ion emission spectrometer. The nickel and copper grades of high-grade concentrate were 4.88% and 2.15%, and those of low-grade concentrate were 1.61% and 0.77%, respectively. The total nickel and copper recoveries were 74.21% and 60.55%, respectively.

[0050] The comparative data of nickel and copper grades obtained in the above three embodiments are shown in Table 1 below:

[0051] Table 1 Comparison of nickel and copper grades

[0052]

[0053] It can be seen from the data in Table 1 that after the beneficiation method provided by the present invention is used to select high-magnesium low-grade copper-nickel sulfide ore, the total nickel recovery rate reaches an average of 73.57%, and the total copper recovery rate reaches an average of 69.46%, which improves the recovery rate of nickel-copper metals and the nickel-copper grade of the concentrate, reduces the magnesium content in the concentrate, achieves the purpose of effectively selecting high-magnesium low-grade copper-nickel sulfide ore, and improves the utilization rate of mineral resources.

Claims

1. A method for beneficiating a high-magnesium, low-grade copper-nickel sulfide ore, characterized in that: The following steps are involved: Step 1: Crushing, grinding and classification. The raw ore is coarsely crushed and then semi-autogenous milled. The ore pulp discharged from the semi-autogenous mill is screened, and the ore on the screen is returned to the semi-autogenous mill. The ore under the screen enters the ball mill. During ball milling, carbonate is added to adjust the pH value of the ore pulp to 8.5-9.5; the ball mill discharge enters the first hydrocyclone for primary classification, and the coarse-grained grit product of the primary classification enters the Isa mill for fine grinding. The fine-grained overflow product of the primary classification and the Isa mill discharge enter the second hydrocyclone for secondary classification. The secondary classification obtains the coarse-grained grit product and the fine-grained overflow product; Step 2: adding inhibitors, collectors and auxiliary collectors to the fine-grained overflow product obtained by secondary classification in step 1 under stirring, performing a flotation roughing to produce a roughing concentrate and a roughing tailings, and the roughing tailings are subjected to two scavengings to produce a primary scavenging concentrate, a secondary scavenging concentrate and a final tailings; Step 3: adding a collector and an auxiliary collector to the coarse-grained grit product obtained by secondary classification in step 1 under stirring, and performing a flotation roughing process to produce a roughing concentrate and a roughing tailing; Step 4: Feed the roughing tailings in step 3 into the third hydrocyclone for three-stage classification, ball mill the coarse-grained sand settling products obtained by the three-stage classification, and return the ball mill discharge to the third hydrocyclone for classification circulation; add collectors and auxiliary collectors to the fine-grained overflow products obtained by the three-stage classification under stirring, and then perform two scavengings to produce primary scavenged concentrates, secondary scavenged concentrates and final tailings; Step 5: The rougher concentrate obtained in step 2 and step 3 is subjected to two rounds of concentration to produce high-grade concentrate, primary concentrated tailings and secondary concentrated tailings; Step 6: The scavenging concentrate, tailings and concentrating tailings obtained in steps 2, 4 and 5 are mixed and concentrating is performed twice to produce low-grade concentrate, primary concentrating tailings and secondary concentrating tailings. The secondary concentrating tailings are returned to the third hydrocyclone in step 4 for classification circulation.

2. The beneficiation method of a high-magnesium low-grade copper-nickel sulfide ore according to claim 1, characterized in that: The amount of carbonate added in step 1 is 0-3 kg / t.

3. The beneficiation method of a high-magnesium low-grade copper-nickel sulfide ore according to claim 1, characterized in that: The inhibitor is carboxymethyl cellulose, the collector is xanthate, and the auxiliary collector is black medicine.

4. The beneficiation method of a high-magnesium low-grade copper-nickel sulfide ore according to claim 3, characterized in that: The addition amount of the inhibitor is 0-500g / t; the addition amount of the collector is 100-400g / t, and the addition amount of the auxiliary collector is 50-100g / t.

5. The beneficiation method of a high-magnesium low-grade copper-nickel sulfide ore according to claim 1, characterized in that: In the step 1, the ball mill feed particle size is -18mm, and the grinding concentration is 50%-70%.

6. A method for beneficiating a high-magnesium, low-grade copper-nickel sulfide ore according to any one of claims 1 to 5, characterized in that: In the step 1, the overflow product with a particle size less than 280 mesh in the second hydrocyclone accounts for more than 90%, and the concentration is 20%-40%.

7. A method for beneficiating a high-magnesium, low-grade copper-nickel sulfide ore according to any one of claims 1 to 5, characterized in that: In the step 4, the overflow product with a particle size less than 200 mesh in the third hydrocyclone accounts for more than 90%, and the concentration is 20%-40%.

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