Beneficiation method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings

Abstract

The invention belongs to a mineral separation technology, and relates to a beneficiation method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings. The method comprises the following steps: firstly, carrying out primary grading on the low-alkalinity high-sulfur copper tailings, feeding settled sand subjected to primary grading into a roughing stirring barrel, adding water for size mixing, then adding a composite collecting agent and a foaming agent, and obtaining high-sulfur-grade sulfur concentrate 1 under the condition of one-time roughing, two-time sweeping and two-time concentration; primary grading overflow is subjected to secondary grading, secondary grading settled sand enters a fine grain stirring barrel, water is added for size mixing, then a composite collecting agent and a foaming agent are added for one-time roughing, two-time sweeping and two-time refining operation, high-sulfur-grade sulfur concentrate 2 is obtained, and fine sulfur roughing concentrate and fine grain sweeping concentrate I enter fine sulfur concentrate I; secondary grading overflow enters a thickener, a flocculating agent is added, the concentration of underflow of the thickener is adjusted to 30%-35%, and the underflow returns to the fine sulfur sweeper I; the method has the advantages of being low in cost, wide in applicability and the like, and efficient flotation recovery of the pyrite can be achieved.

Description

Technical Field

[0001] The invention belongs to mineral separation technology and relates to a mineral separation method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings. Background Art

[0002] As an important chemical raw material, pyrite is widely used in the production of chemical products such as sulfuric acid and sulfur. In the sorting process of non-ferrous metal sulfide ores, in order to improve the grade and recovery rate of the main metal, pyrite is often suppressed and left in the tailings. The suppressed or removed iron sulfide minerals are often stored in the tailings pond together with other gangue minerals, or enriched to obtain sulfur concentrate and sent to the sulfuric acid plant. In the tailings pond, the long-term storage of iron sulfide minerals will have a serious impact on the ecological environment around the mining area. For example, sulfur-containing tailings are prone to produce acid mine drainage due to long-term natural oxidation, resulting in abnormal pH of the water body and increased concentration of heavy metal ions. In addition, if the sulfur content of the tailings is too high, it is also easy to spontaneously combust due to local high temperature caused by sulfur oxidation, which poses a great safety risk. Therefore, improving the recovery rate of the beneficiation of co-existing iron sulfide minerals and reducing the sulfur content of the tailings are of great significance to environmental protection and resource recycling.

[0003] Due to its low economic value and other reasons, the industry often uses lime as a pyrite inhibitor to recover other high-priced metals under high-alkalinity conditions, and pyrite is often left in the tailings. The high-alkalinity copper-sulfur separation process will cause the associated precious metals to be suppressed by high alkalinity, which is detrimental to the equipment and the environment. In addition, a large amount of sulfuric acid needs to be added as an activator during the sulfur recovery stage, and the pH value of the mineral processing wastewater is relatively high. With increasingly stringent environmental protection policies, the low-alkalinity copper-sulfur separation process has gradually replaced the high-alkalinity copper-sulfur separation process. For this reason, it is urgent to design a mineral processing method for flotation recovery of pyrite from low-alkalinity, high-sulfur copper tailings, so as to further improve the economic, social and ecological benefits of mines and promote the green and high-quality development of mines. Summary of the invention

[0004] The invention discloses a beneficiation method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings, so as to solve any of the above and other potential problems in the prior art.

[0005] In order to solve the above technical problems, a beneficiation method for flotation recovery of pyrite from low-alkalinity and high-sulfur copper tailings is provided, the beneficiation method specifically comprising the following steps:

[0006] S1) the low-alkalinity high-sulfur copper tailings to be treated are subjected to a primary classification, the primary classification sedimentation enters a roughing mixing barrel, water is added to prepare the slurry, and then a composite collector and a frother are added to obtain a high-sulfur grade sulfur concentrate 1 and tailings 1 under the conditions of one roughing, two sweeping and two refining;

[0007] S2) the overflow from the primary classification is subjected to secondary classification, the secondary classification sedimentation enters the fine particle mixing barrel, water is added to prepare the slurry, and then a composite collector and a frother are added to perform one roughing, two sweeping and two fine operations to obtain a high-sulfur grade sulfur concentrate 2 and tailings 2;

[0008] S3) The secondary overflow is then sent to the thickener, where flocculants are added to control the underflow concentration, and then pumped to the sand box of the fine sulfur sweep I flotation machine to complete the recovery.

[0009] Furthermore, the fine sulfur roughing concentrate and fine-grained sweep I concentrate in S2) enter the fine sulfur concentrate I.

[0010] Furthermore, it is characterized in that the primary classification pressure in S1) is 0.11-0.15 MPa.

[0011] Further, the crude sulfur sweep I and crude sulfur refine I in S1) are returned to the primary classification sand settling tank, a water replenishment point is set in the sand settling tank, and the slurry in the sand settling tank is transported to the crude sulfur stirring tank through a pipeline, and the slurry concentration value of the crude sulfur stirring tank is 42% to 50%;

[0012] Furthermore, the secondary classification sand settling in S2) is transported to the fine sulfur stirring tank through a pipeline, and the slurry concentration value of the coarse sulfur stirring tank is 30% to 35%.

[0013] Furthermore, in said S1) and S2), the amount of composite collector for crude sulfur selection is 25-30 g / t, the amount of foaming agent is 5-10 g / t, the amount of composite collector for crude sulfur sweep I is 10-15 g / t, the amount of composite collector for crude sulfur sweep II is 5-10 g / t, the amount of composite collector for crude sulfur refinement II is 3-5 g / t, the amount of collector for fine sulfur sweep I is 15-20 g / t, and the amount of collector for fine sulfur sweep II is 5-10 g / t.

[0014] Furthermore, the composite collector includes ethylthiocyanate, isobutyl xanthate and isopentyl xanthate, and the mass ratio of the three is 2:5:3;

[0015] The composite collector is added at a mass concentration of 5%;

[0016] The foaming agent used is 2# oil.

[0017] Further, the amount of flocculant in S3) is 5-15 g / t, and the underflow concentration is adjusted to 30%-35%;

[0018] The flocculant is polyacrylamide.

[0019] Furthermore, the sulfur recovery rate of the ore dressing method reaches 90.44%, and the sulfur grade in the sulfur concentrate product reaches 46.36%.

[0020] A sulfur concentrate is obtained by using the above-mentioned mineral processing method.

[0021] The beneficial effects of the present invention are: due to the adoption of the above technology, the method of the present invention utilizes the composite collector to simultaneously improve the grade of the product, greatly improves the sulfur recovery rate, and has the advantages of low cost and wide applicability, and can achieve efficient flotation recovery of pyrite. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the present invention is further described below in conjunction with the accompanying drawings.

[0023] Figure 1 The present invention is a process flow chart of a mineral processing method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described below with reference to the accompanying drawings.

[0025] like Figure 1 As shown, the present invention provides a flotation beneficiation method for recovering pyrite from low-alkalinity high-sulfur copper tailings, characterized in that the low-alkalinity high-sulfur copper tailings are subjected to primary classification, the primary classification sand is discharged into a roughing stirring barrel, and a high-sulfur grade sulfur concentrate 1 is obtained under the conditions of one roughing, two sweeping and two refining; the overflow of the primary classification is subjected to secondary classification, and the secondary classification sand is discharged to perform one roughing, two sweeping and two refining operations to obtain a high-sulfur grade sulfur concentrate 2, wherein the fine sulfur roughing concentrate and the fine-grained sweep I concentrate enter the fine sulfur concentrate I; the overflow of the secondary classification enters the thickener, and is concentrated and dehydrated and returned to the fine sulfur sweep I.

[0026] Preferably, the primary classification pressure is 0.11-0.15 MPa.

[0027] Preferably, the crude sulfur sweep I and the crude sulfur refine I tail are returned to the primary classification grit tank, a water replenishing point is set in the grit tank, the slurry in the grit tank is transported to the crude sulfur stirring barrel through a pipeline, and the slurry concentration in the crude sulfur stirring barrel is 42% to 50%; the secondary classification grit is transported to the fine sulfur stirring barrel through a pipeline, and the slurry concentration in the crude sulfur stirring barrel is 30% to 35%.

[0028] Preferably, sulfur concentrate 1 and tailings 1 are obtained in the process of one roughing, two sweeping and two finishing in the first classification and sand settling; sulfur concentrate 2 and tailings 2 are obtained in the process of one roughing, two sweeping and two finishing in the second classification and sand settling, wherein the fine sulfur roughing concentrate and the fine sulfur sweeping I concentrate enter the fine sulfur finishing; the overflow from the second classification is dehydrated and concentrated to 30% to 35% through a thickener, and then returned to the fine particle sweeping I.

[0029] Preferably, the composite collectors used are ethylthiocyanate, isobutyl xanthate and isopentyl xanthate, and the added mass ratio is 2:5:3; the foaming agent used is 2# oil, and the flocculant is polyacrylamide, wherein the amount of crude sulfur composite collector is 25-30 g / t, the amount of foaming agent is 5-10 g / t, the amount of crude sulfur sweep I composite collector is 10-15 g / t, the amount of crude sulfur sweep II composite collector is 5-10 g / t, the amount of crude sulfur fine II composite collector is 3-5 g / t, the amount of fine sulfur rough selection composite collector is 15-20 g / t, the amount of foaming agent is 3-5 g / t, the amount of fine sulfur sweep I composite collector is 15-20 g / t, the amount of fine sulfur sweep II composite collector is 5-10 g / t, and the amount of thickener flocculant is 5-15 g / t.

[0030] Preferably, the low-alkalinity high-sulfur copper tailings are copper tailings separated by a low-alkalinity copper-sulfur separation process.

[0031] Example 1

[0032] The mineral raw material is high-sulfur copper tailings from a copper concentrator in Jiangxi, with a pH value of 8-9.5 and a sulfur grade of 8-12%. The gangue minerals are mainly quartz and aluminosilicate. The dosage of the reagents is shown in Table 1. The test is an industrial on-site commissioning.

[0033] Table 1 Example 1 Dosage of medicine

[0034]

[0035] The specific steps are as follows:

[0036] (1) The high-sulfur copper tailings are classified once through a φ300 hydrocyclone with a classification pressure of 0.13 MPa. Collectors and frothers are added in sequence. The roughing operation time is 6 minutes, followed by two scavenging operations, each of which takes 6 minutes. Two concentrating operations, each of which takes 4 minutes, are performed to obtain sulfur concentrate 1 and tailings 1. The intermediate products are returned in sequence. The return points of scavenging I and tailings I are the first classification sand settling tanks.

[0037] (2) The overflow from the primary classification is passed through a φ150 hydrocyclone for secondary classification, with a classification pressure of 0.15 MPa; collectors and frothers are added in sequence, with a roughing operation time of 6 minutes, two scavenging operations, each scavenging operation time of 6 minutes, and two concentrating operations, each concentrating operation time of 4 minutes, to obtain sulfur concentrate 2 and tailings 2. Among them, the fine sulfur roughing concentrate and fine sulfur scavenging I concentrate enter the fine sulfur concentrating, and the remaining intermediate products are returned in sequence, and the return point of the fine sulfur concentrate I tailings is the secondary classification sand settling tank.

[0038] (3) The secondary overflow enters the φ18m thickener, the underflow concentration is controlled at 30% to 35%, and is pumped to the sand box of the fine sulfur sweep I flotation machine.

[0039] (4) Table 2 shows the flotation product indicators of Example 1.

[0040] Table 2 Flotation product indicators of Example 1

[0041] Job Products Yield / % grade / % Recovery rate / % Sulfur concentrate 17.85 46.36 90.44 Tailings 82.15 1.07 9.56 Ore 100.00 9.15 100.00

[0042] From the results in Table 2, it can be seen that the sulfur recovery rate of the high-sulfur copper tailings reached 90.44% after secondary classification and coarse and fine separation, and a relatively high sulfur recovery rate was obtained. The sulfur grade in the sulfur concentrate product reached 46.36%, and high-quality concentrate indicators were obtained.

[0043] Example 2

[0044] The mineral raw materials used in this example are the same as those in Example 1, and the dosage of the reagents is shown in Table 3. The test is an industrial on-site commissioning.

[0045] Table 3 Example 2 dosage

[0046]

[0047] The specific steps are as follows:

[0048] (1) The high-sulfur copper tailings are classified once through a φ300 hydrocyclone with a classification pressure of 0.12 MPa. Collectors and frothers are added in sequence. The roughing operation time is 5 minutes. The scavenging is performed twice, each scavenging time is 5 minutes. The concentrating is performed twice, each concentrating time is 4 minutes. Sulfur concentrate 1 and tailings 1 are obtained. The intermediate products are returned in sequence. The return points of scavenging I and tailings I are the first classification sand settling tank.

[0049] (2) The overflow from the primary classification is passed through a φ150 hydrocyclone for secondary classification, with a classification pressure of 0.15 MPa; collectors and frothers are added in sequence, with a roughing operation time of 5 minutes, two scavenging operations, each scavenging operation time of 5 minutes, and two concentrating operations, each concentrating operation time of 4 minutes, to obtain sulfur concentrate 2 and tailings 2. Among them, the fine sulfur roughing concentrate and fine sulfur scavenging I concentrate enter the fine sulfur concentrating, and the remaining intermediate products are returned in sequence, and the return point of the fine sulfur concentrate I tailings is the secondary classification sand settling tank.

[0050] (3) The secondary overflow enters the φ18m thickener, the underflow concentration is controlled at 30% to 35%, and is pumped to the sand box of the fine sulfur sweep I flotation machine.

[0051] (4) Table 4 shows the flotation product indicators of Example 1.

[0052] Table 4 Flotation product index of Example 2

[0053] Job Products Yield / % grade / % Recovery rate / % Sulfur concentrate 18.27 45.84 91.53 Tailings 81.73 0.95 8.47 Ore 100.00 9.15 100.00

[0054] From the results in Table 4, it can be seen that the sulfur recovery rate of the high-sulfur copper tailings reached 91.53% after secondary classification and coarse and fine separation, and a relatively high sulfur recovery rate was obtained. The sulfur grade in the sulfur concentrate product reached 45.84%, and high-quality concentrate indicators were obtained.

[0055] Example 3

[0056] The mineral raw materials used in this example are the same as those in Example 1, and the dosage of the reagents is shown in Table 5. The test is an industrial on-site commissioning.

[0057] Table 5 Example 2 dosage

[0058]

[0059] The specific steps are as follows:

[0060] (1) The high-sulfur copper tailings are classified once through a φ300 hydrocyclone with a classification pressure of 0.12 MPa. Collectors and frothers are added in sequence. The roughing operation time is 6 minutes, followed by two scavenging operations, each of which takes 6 minutes. Two concentrating operations, each of which takes 5 minutes, are performed to obtain sulfur concentrate 1 and tailings 1. The intermediate products are returned in sequence, and the return points of scavenging I and tailings I are the first classification sand settling tanks.

[0061] (2) The overflow from the primary classification is passed through a φ150 hydrocyclone for secondary classification, with a classification pressure of 0.15 MPa; collectors and frothers are added in sequence, with a roughing operation time of 6 minutes, two scavenging operations, each scavenging operation time of 6 minutes, and two concentrating operations, each concentrating operation time of 5 minutes, to obtain sulfur concentrate 2 and tailings 2. Among them, the fine sulfur roughing concentrate and fine sulfur scavenging I concentrate enter the fine sulfur concentrating, and the remaining intermediate products are returned in sequence, and the return point of the fine sulfur concentrate I tailings is the secondary classification sand settling tank.

[0062] (3) The secondary overflow enters the φ18m thickener, the underflow concentration is controlled at 30% to 35%, and is pumped to the sand box of the fine sulfur sweep I flotation machine.

[0063] (4) Table 6 shows the flotation product indicators of Example 1.

[0064] Table 6 Flotation product index of Example 3

[0065] Job Products Yield / % grade / % Recovery rate / % Sulfur concentrate 18.71 45.13 92.28 Tailings 81.29 0.87 7.72 Ore 100.00 9.15 100.00

[0066] From the results in Table 6, it can be seen that the sulfur recovery rate of the high-sulfur copper tailings reached 92.28% after secondary classification and coarse and fine separation, and a relatively high sulfur recovery rate was obtained. The sulfur grade in the sulfur concentrate product reached 45.13%, and high-quality concentrate indicators were obtained.

[0067] The above is a detailed introduction to the ore dressing method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings provided in the embodiment of the present application. The description of the above embodiment is only used to help understand the method and its core idea of ​​the present application; at the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as limiting the present application.

[0068] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. As mentioned throughout the specification and claims, "including" and "comprising" are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description of the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be determined by the definition of the attached claims.

[0069] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0070] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0071] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.

Claims

1. A method for flotation recovery of pyrite from low-alkalinity high-sulfur copper tailings, characterized in that: The ore dressing method specifically comprises the following steps: S1) the low-alkalinity high-sulfur copper tailings to be treated are subjected to a primary classification, the primary classification sedimentation enters a roughing mixing barrel, water is added to prepare the slurry, and then a composite collector and a frother are added to obtain a high-sulfur grade sulfur concentrate 1 and tailings 1 under the conditions of one roughing, two sweeping and two refining; S2) the overflow from the primary classification is subjected to secondary classification, the secondary classification sedimentation enters the fine particle mixing barrel, water is added to prepare the slurry, and then a composite collector and a frother are added to perform one roughing, two sweeping and two fine operations to obtain a high-sulfur grade sulfur concentrate 2 and tailings 2; S3) The secondary overflow is then sent to the thickener, where flocculants are added to control the underflow concentration, and then pumped to the sand box of the fine sulfur sweep I flotation machine to complete the recovery.

2. The ore dressing method according to claim 1, characterized in that: The fine sulfur roughing concentrate and fine-grained sweep I concentrate in S2) enter the fine sulfur concentrate I.

3. The ore dressing method according to claim 1, characterized in that: The primary classification pressure in S1) is 0.11-0.15 MPa.

4. The ore dressing method according to claim 1, characterized in that: The crude sulfur sweep I and crude sulfur refinement I in S1) are returned to the primary classification sand settling tank, a water replenishment point is set in the sand settling tank, and the slurry in the sand settling tank is transported to the crude sulfur stirring tank through a pipeline. The slurry concentration value of the crude sulfur stirring tank is 42% to 50%.

5. The ore dressing method according to claim 1, characterized in that: The secondary classification sand settling in S2) is transported to the fine sulfur stirring tank through a pipeline, and the slurry concentration value of the coarse sulfur stirring tank is 30% to 35%.

6. The ore dressing method according to claim 1, characterized in that: The amount of composite collector for crude sulfur selection in S1) and S2) is 25-30 g / t, the amount of foaming agent is 5-10 g / t, the amount of composite collector for crude sulfur sweep I is 10-15 g / t, the amount of composite collector for crude sulfur sweep II is 5-10 g / t, the amount of composite collector for crude sulfur refinement II is 3-5 g / t, the amount of collector for fine sulfur sweep I is 15-20 g / t, and the amount of collector for fine sulfur sweep II is 5-10 g / t.

7. The ore dressing method according to claim 6, characterized in that: The composite collector comprises ethylthiocyanate, isobutyl xanthate and isopentyl xanthate, and the mass ratio of the three is 2:5:3; The composite collector is added at a mass concentration of 5%; The foaming agent used is 2# oil.

8. The ore dressing method according to claim 1, characterized in that: The dosage of the flocculant in S3) is 5-15 g / t, and the underflow concentration is adjusted to 30%-35%; The flocculant is polyacrylamide.

9. The ore dressing method according to claim 1, characterized in that: The sulfur recovery rate of the ore dressing method reaches 90.44%, and the sulfur grade in the sulfur concentrate product reaches 46.36%.

10. A sulfur concentrate, characterized in that: The sulfur concentrate is obtained by the mineral processing method described in any one of claims 1 to 9.

Images