Lime-free efficient flotation process for lead-zinc-silver ore

Abstract

The invention provides a lime-free efficient flotation process for lead-zinc-silver ore, and belongs to the technical field of ore dressing processes. The efficient flotation process solves the problems that in the prior art, the use cost of lime is high, the return water treatment cost needs to be improved, and the product quality needs to be improved. The flotation process provided by the invention has the following effects: the lime consumption is reduced, and the lime cost is saved by about 3 million yuan per year. The product quality is improved, the arsenic impurity content in the zinc concentrate is reduced from 2% to below 0.8%, the economic benefit is improved by about 280,000 yuan per year, the copper grade in the lead concentrate is improved from 1.7% to above 2%, and the economic benefit is improved by about 7,000,000 yuan per year. The pH value in the pond is reduced from 11 to 7, and the surrounding environment of the tailing pond is improved. The Ca < 2 + > concentration in the tailing pond return water is reduced, the pipeline structure influence is reduced, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of ore dressing technology, and in particular to a lime-free and efficient flotation process for lead-zinc-silver ore. Background Art

[0002] The lead, zinc and silver beneficiation process is a priority flotation process, that is, lead is selected first and zinc is selected later. Lime must be added during the lead and zinc selection process to improve the grade and quality of lead concentrate and zinc concentrate; the traditional lead and zinc flotation collector is ethylthiocyanate or ethyl xanthate or black medicine or butyl xanthate, etc., the inhibitor is zinc sulfate and lime, the activator is copper sulfate, and the foaming agent is 2# oil. More than 85% of the water used for beneficiation is clarified return water in the tailings pond. Generally, the amount of lime used is about 5-13Kg / ton of ore. The large amount of lime used leads to a high cost of reagents. At the same time, the addition of a large amount of lime causes the pH value of the return water in the tailings pond to be high, and the surrounding environment of the reservoir is poor. In addition, due to the large amount of lime calcium ions in the return water, the return water pipes and slurry pipes are often scaled, and the pipes are often blocked, affecting production and affecting production efficiency. During production, lime often splashes on the site, which also makes the on-site environmental sanitation quality poor. In the return water treatment, sulfuric acid is required to neutralize the water quality so that the pH value of the return water reaches medium before reuse.

[0003] Chinese patent CN108176515A discloses a lead-zinc ore dressing process method that can significantly reduce the consumption of clean water for ore dressing and significantly save clean water resources, and can stably improve the lead-zinc ore dressing index, reduce the discharge of ore dressing wastewater, and reduce environmental pollution. The lead-zinc ore dressing process method uses the lead tailings of the lead tailings to directly return for ball milling and lead selection, uses the zinc tailings of the zinc tailings to directly return for zinc selection, and uses the tailings of the sulfur tailings to directly return for sulfur selection, which can significantly save the amount of clean water.

[0004] However, the existing technology has not solved the problems of high lime use cost, return water treatment cost, and product quality that needs to be improved. Summary of the invention

[0005] The object of the present invention is to provide a lime-free and efficient flotation process for lead-zinc-silver ore, which can effectively avoid lime use costs and return water treatment costs and improve product quality.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a lime-free and efficient flotation process for lead-zinc-silver ore, comprising the following steps:

[0008] S1. Crushing, ball milling and classifying the raw ore in sequence to obtain ore pulp;

[0009] S2, mixing the slurry with zinc inhibitor and lead collector, and entering the lead roughing operation;

[0010] S3. After the lead roughing operation, the pulp is subjected to the lead concentration operation to obtain the lead concentrate product, and the lead tailings are obtained through the lead scavenging operation, and then enter the zinc flotation operation;

[0011] S4, mixing the lead tailings with a sulfur inhibitor to obtain a mixture;

[0012] S5, mixing the mixture with a zinc collector and entering a zinc roughing operation;

[0013] S6. After the zinc roughing operation, the slurry is subjected to the zinc concentration operation to obtain the zinc concentrate product, and the tailings part is obtained through the zinc scavenging operation.

[0014] Preferably, the concentration of the slurry after ball milling is 20-40%.

[0015] Preferably, the fineness of the slurry is 200 mesh.

[0016] Preferably, the concentration of the slurry is 60-80%.

[0017] Preferably, the zinc inhibitor is D82 and the lead collector is Q77.

[0018] Preferably, the dosage of the zinc inhibitor is 800-1200 g / t;

[0019] The dosage of the lead collector is 80-100 g / t.

[0020] Preferably, no lime is added to S2.

[0021] Preferably, the sulfur inhibitor is D52 and the zinc collector is Q66.

[0022] Preferably, the amount of the sulfur inhibitor is 400-600 g / t;

[0023] The dosage of the zinc collector is 20-40 g / t.

[0024] Preferably, the tailings are partially pumped into a tailings pond or partially pumped into a filling station for tailings filling.

[0025] Beneficial effects of the present invention:

[0026] The original lead-zinc-silver beneficiation reagent must be alkaline, that is, lime must be added before the lead-zinc-silver ore can be floated. The flotation process provided by the present invention does not need to add lime, saving the cost of lime. After the tailings slurry enters the tailings pond, the original process causes the pH value of the return water in the tailings pond to be high, which has a certain degree of impact on the surrounding environment of the tailings pond. When the return water in the tailings pond is used or discharged, the return water must be treated, that is, acid is added for neutralization, and the pH value of the return water reaches medium before it can be discharged or reused. The new reagent can be directly reused or discharged without treatment, saving the cost of return water treatment.

[0027] The grade of copper associated with lead concentrate products was only about 1.7% when the original process was used. The use of new environmentally friendly agents can make the grade of copper associated with lead concentrate reach more than 2%, reaching the minimum smelting price, creating about 7 million yuan of economic benefits for the mine every year. The arsenic impurity content in zinc concentrate products was more than 1.5% in the original process, and the arsenic impurities seriously exceeded the standard, seriously affecting the quality of zinc concentrate products. After using the new environmentally friendly agents, the arsenic impurity content in zinc concentrate products is below 0.5%, meeting the quality requirements of zinc concentrate products, creating about 3 million yuan of benefits for the company every year.

[0028] When using the original common reagents, the on-site environment of the ore dressing operation is relatively poor, especially in the lime milk preparation workshop and the flotation workshop, lime splashes everywhere. The flotation process provided by the present invention improves the on-site production environment and the occupational health of employees. The addition of lime to the slurry causes various flotation pipelines, especially the return water pipeline and the slurry pipeline, to be blocked due to frequent scaling, which seriously affects production and has low production efficiency. The flotation process provided by the present invention improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a process flow chart of the present invention;

[0030] Figure 2 This is a graph showing the results of the assay of arsenic impurities in refined zinc during the process of the present invention;

[0031] Figure 3 This is the result of the analysis of arsenic impurities in the original reagent zinc concentrate;

[0032] Figure 4 This is a graph showing the results of the assay of arsenic impurities in refined zinc during the process of the present invention;

[0033] Figure 5 This is a copper grade result diagram of the process test report of the present invention;

[0034] Figure 6 This is the copper grade result chart of the original reagent test report. DETAILED DESCRIPTION

[0035] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0036] The raw ore of a lead-zinc-silver mine contains lead, zinc, silver and a small amount of associated copper elements. The grades of lead, zinc and silver in the raw ore are 2.7%, 2.6% and 85g / t respectively. The ore dressing process is preferential flotation, and the main purpose is to use physical and chemical methods to enrich the useful elements in the raw ore, namely lead, zinc, silver and the target minerals, namely galena and sphalerite, to meet the smelting standards. Before 2024, the main chemical ore dressing agents used in ore dressing production were ethylthionitrile, black medicine, copper sulfate, zinc sulfate, butyl xanthate, 2# oil and a large amount of lime. The dosages are 200g / t, 10g / t, 600g / t, 1000g / t, 200g / t, 40g / t and 13000g / t respectively, among which lime is the largest reagent cost.

[0037] The new mineral processing environmental protection agents D82, D52, Q66 and Q77 used in the embodiments of the present invention are produced by Hunan Huaqi Resources and Environment Technology Development Company.

[0038] Example

[0039] The raw ore containing lead, zinc and silver is ① crushed and ground into a 30% concentration in a ② ball mill, and then graded in a ③ cement cyclone group, and the overflow slurry fineness is about 70% of the -200 mesh;

[0040] Instead of adding lime to the slurry to keep the pH value of the slurry above 10, new environmentally friendly lead dressing agents are added into the ④1# lifting and mixing barrel: zinc inhibitor D82 of about 1000g / t, lead collector Q77 of about 90g / t, the slurry passes through ⑤ lead roughing foam and enters ⑦ lead concentration to obtain lead concentrate products, and the slurry passes through ⑥ lead scavenging to obtain lead tailings that enter zinc flotation operation.

[0041] The lead tailings pass through ⑧2# mixing barrel, and zinc activator copper sulfate and sulfur inhibitor D52 (about 500g / t) are added therein and flow into ⑨3# mixing barrel by gravity. About 30g / t zinc collector Q66 is added into 3# mixing barrel. After sufficient stirring, they enter ⑩ zinc roughing operation for flotation. The flotation foam enters zinc concentration operation to obtain zinc concentrate product. The flotation slurry enters zinc scavenging operation. Part of the tailings is pumped into the tailings pond and part is pumped into the filling station for tailings filling.

[0042] Flowchart as Figure 1 shown.

[0043] Comparative Example

[0044] Original process:

[0045] The raw ore containing lead, zinc and silver is ① crushed and ground into a 30% concentration in a ② ball mill, and then graded in a ③ cement cyclone group, and the overflow slurry fineness is about 70% of the -200 mesh;

[0046] Lime is added to the slurry to keep the pH value of the slurry above 10. At the same time, lead ore dressing reagents are added to the ④1# lifting and stirring barrel: zinc inhibitor zinc sulfate, collector ethyl dithiocarb, and black medicine. The slurry passes through the ⑤ lead roughing foam and enters the ⑦ lead concentration to obtain the lead concentrate product. The slurry passes through the ⑥ lead scavenging to obtain the lead tailings and enter the zinc flotation operation.

[0047] Lead tailings pass through the ⑧2# mixing barrel, and copper sulfate, a zinc activator, and lime, a sulfur inhibitor, are added to it and flow into the ⑨3# mixing barrel. Zinc collector butyl xanthate is added to the 3# mixing barrel. After sufficient stirring, it enters the ⑩ zinc roughing operation for flotation. The flotation foam enters Zinc concentrate is obtained from zinc concentration operations, and the flotation slurry enters Part of the zinc scavenging tailings is pumped into the tailings pond and part is pumped into the filling station for tailings filling.

[0048] Depend on Figure 2 As shown, the process of the present invention uses a new agent zinc concentrate arsenic impurity test result of less than 0.8%;

[0049] Depend on Figure 3 As shown, the arsenic impurity test result of the original reagent zinc concentrate is more than 1.5%;

[0050] Depend on Figure 5 As shown, the copper grade of the new reagent test report can reach more than 2%;

[0051] Depend on Figure 6 As shown, the copper grade in the original ordinary chemical test report was only about 1.7%.

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A limeless and efficient flotation process for lead, zinc and silver ores, characterized in that: The following steps are involved: S1. Crushing, ball milling and classifying the raw ore in sequence to obtain ore pulp; S2, mixing the slurry with zinc inhibitor and lead collector, and entering the lead roughing operation; S3. After the lead roughing operation, the pulp is subjected to the lead concentration operation to obtain the lead concentrate product, and the lead tailings are obtained through the lead scavenging operation, and then enter the zinc flotation operation; S4, mixing the lead tailings with a sulfur inhibitor to obtain a mixture; S5, mixing the mixture with a zinc collector and entering a zinc roughing operation; S6. After the zinc roughing operation, the slurry is subjected to the zinc concentration operation to obtain the zinc concentrate product, and the tailings part is obtained through the zinc scavenging operation.

2. The lime-free efficient flotation process for lead-zinc-silver ore according to claim 1, characterized in that: The concentration of the ore pulp after ball milling is 20-40%.

3. The lime-free efficient flotation process for lead-zinc-silver ore according to claim 1, characterized in that: The fineness of the slurry is 200 mesh.

4. The lime-free efficient flotation process for lead-zinc-silver ore according to claim 3 is characterized in that: The concentration of the ore pulp is 60-80%.

5. The lime-free efficient flotation process for lead-zinc-silver ore according to claim 1, characterized in that: The zinc inhibitor is D82, and the lead collector is Q77.

6. The lime-free efficient flotation process for lead-zinc-silver ore according to claim 5, characterized in that: The dosage of the zinc inhibitor is 800-1200 g / t; The dosage of the lead collector is 80-100 g / t.

7. The lime-free efficient flotation process for lead-zinc-silver ore according to claim 5, characterized in that: No lime is added to the S2.

8. The limeless and efficient flotation process for lead-zinc-silver ore according to claim 1, characterized in that: The sulfur inhibitor is D52, and the zinc collector is Q66.

9. The limeless and efficient flotation process for lead-zinc-silver ore according to claim 8, characterized in that: The amount of the sulfur inhibitor is 400-600 g / t; The dosage of the zinc collector is 20-40 g / t.

10. The limeless and efficient flotation process for lead-zinc-silver ore according to any one of claims 1 to 9, characterized in that: The tailings are partially pumped into a tailings pond or partially pumped into a filling station for tailings filling.

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