CN111330751B

CN111330751B - Combined process for recovering antimony, lead and gold from multi-metal tailings

Info

Publication number: CN111330751B
Application number: CN201811560924.1A
Authority: CN
Inventors: 陈勇; 宋永胜; 李文娟; 张其东
Original assignee: GRINM Resources and Environment Technology Co Ltd
Current assignee: GRINM Resources and Environment Technology Co Ltd
Priority date: 2018-12-19
Filing date: 2018-12-19
Publication date: 2021-11-19
Anticipated expiration: 2038-12-19
Also published as: CN111330751A

Abstract

The invention discloses a combined process for recovering antimony, lead and gold from multi-metal tailings. The combined process comprises the following steps: (1) pretreating tailings: placing the tailing materials into a stirring barrel for size mixing and scrubbing, and then adding a flocculating agent for selective flocculation; (2) performing superfine purification and classification by using a superfine purification classifier to remove fine mud below 2 microns; (3) and (3) enabling settled sand to enter a hydrocyclone for classification, enabling classification underflow to grind, then returning to the hydrocyclone for classification, and enabling classification overflow to float to obtain bulk concentrates. The process greatly improves the recovery rate of valuable elements in the tailings by the measures of pretreatment, superfine purification and desliming of the tailings, construction of a selective grinding loop and the like, and greatly improves the desliming effect.

Description

Combined process for recovering antimony, lead and gold from multi-metal tailings

Technical Field

The invention relates to a combined process for recovering antimony, lead and gold from multi-metal tailings, belonging to the technical field of mineral separation.

Background

The old tailings piled in the polymetallic sulphide ore mine in China contain not only precious metals, nonferrous metals and ferrous metal minerals, but also a large amount of nonmetallic minerals, the lost metallic minerals mostly exist as intergrowths, fine grains or micro-fine grains, both sulphide minerals and oxide minerals exist, and the surfaces of part of sulphide minerals are oxidized due to long-time piling. The properties of the tailings are complex, and the recyclable value is high. For example, lead-antimony-zinc minerals in Guangxi Daicheng are not uniform in the embedded particle size, are mainly embedded with fine particles, are brittle, and gangue minerals are mainly granite with extremely high hardness, so that crushing is caused in the crushing and grinding processes. Along with continuous fine grinding, the amount of slime produced in the production process is continuously increased, part of slime of micro-fine lead and zinc is difficult to settle and is lost in overflow, and part of slime of micro-fine zinc is lost in lead-sulfur separation tailings. The research data of the car and river separation plant show that the fine lead (antimony) metal lost in the overflow of the thickener and the lead-sulfur separation tailings accounts for 7.54 percent of the raw ore, the zinc accounts for 5.82 percent, the granularity is between 1 and 5 microns, and the potential value of the lead-sulfur separation tailings is very high. Because the fine mud has large specific surface area, high specific surface energy and very complex properties, the fine mud is difficult to settle and is not well recovered and lost in tailings all the time.

Flotation is extremely inefficient in recovering particles in the size fraction of greater than 100 microns or less than 5 microns. Coarse fraction metal recovery is low because the heavy or medium particles that have dissociated cannot be hydrodynamically attached to the froth layer, while the fine particles, which are too finely ground, are less than 5 microns and difficult to float because of the lack of sufficient potential energy to form a particle-froth attachment with the froth, both losses that are very common and important in the flotation process. The valuable elements lost in the slime are difficult to recover, and another important reason is that the slime is generally high in content, small in quality, high in surface energy and high in activity, and if the slime is directly floated, the slime can not selectively adsorb a collecting agent, flotation foam is sticky while a large amount of reagents are consumed, mechanical entrainment of gangue minerals is aggravated, and even flotation cannot be carried out.

Therefore, it is necessary to develop a new process for efficiently recovering valuable minerals (Pb, Sb, etc.) or encapsulated/intergrowth minerals (Au) lost due to the over-ground minerals in the multi-metal tailings, eliminating the interference of fine-particle mud, and reducing the loss of the valuable minerals in the desliming process.

Disclosure of Invention

The invention aims to provide a combined process for recovering antimony, lead and gold from multi-metal tailings, so as to improve the recovery rate of useful elements, improve the desliming effect, shorten the flotation process and save the cost.

In order to achieve the purpose, the invention adopts the following technical scheme:

a combined process for recovering antimony, lead and gold from polymetallic tailings comprises the following steps:

(1) pretreating tailings: placing the tailing materials into a stirring barrel for size mixing and scrubbing, and then adding a flocculating agent for selective flocculation;

(2) performing superfine purification and classification by using a superfine purification classifier to remove fine mud below 2 microns;

(3) and (3) enabling settled sand to enter a hydrocyclone for classification, enabling classification underflow to grind, then returning to the hydrocyclone for classification, and enabling classification overflow to float to obtain bulk concentrates.

The invention firstly carries out scrubbing-selective flocculation pretreatment on the tailing materials, and after the pretreatment, monomer minerals of useful minerals with micro-fine particles can be effectively flocculated into large particles so as to achieve the optimal flotation particle size; the desliming of the superfine purification classifier is used for replacing the desliming of the traditional gravity separation equipment, so that the desliming precision is greatly improved; the inclusion and the intergrowth are accurately ground by the constructed selective grinding circuit, and the monomer dissociation degree of the minerals is further improved. The process greatly improves the recovery rate of valuable elements in the tailings by the measures of pretreatment, superfine purification and desliming of the tailings, construction of a selective grinding loop and the like, and greatly improves the desliming effect.

In the step (1), the concentration after size mixing is 10-20% (solid-liquid weight ratio), and the stirring strength is 1500-. The added flocculating agent is one or more of hydrolyzed polyacrylamide, polyacrylonitrile and sodium fluoride, and the dosage is 5-50 g/t.

In the step (2), the pulp conditioning concentration of the ore pulp of the superfine purification classifier is 5-10% (solid-liquid weight ratio), and the working pressure is 0.65-0.85 Mpa.

In the step (3), the fineness of the classification underflow grinding ore is 85-90% of-0.038 mm.

In the step (3), the flotation regulator is sodium carbonate, the dosage is 500-1000g/t, the pH value is 7-8, the activating agent is one or two of copper sulfate and lead nitrate, the dosage is 100-600g/t, the collecting agent is one or two of butyl sodium xanthate and butyl ammonium melanophore, the dosage is 50-300g/t, and the flotation time is 8-20 min.

In the step (3), the flotation process structure comprises one roughing, two scavenging and two fine concentration.

The invention has the advantages that:

the process greatly improves the flocculation granularity of useful minerals after the tailings are pretreated, remarkably removes fine mud with the grain size of-2 mu m by a superfine purification system, eliminates the adverse effect of the fine mud on flotation, and plays a certain role in pre-enrichment; and by constructing a selective ore grinding loop, the monomer dissociation degree of the intergrowth/inclusion is improved, the recovery rate of antimony, lead and gold elements is improved, the flotation process is shortened, the medicament and the power consumption are saved, and good economic benefits can be brought to enterprises.

Drawings

FIG. 1 is a process flow diagram of the present invention.

Fig. 2 is a flow chart of a traditional process for recovering valuable elements from tailings.

Detailed Description

The present invention is further illustrated by the following examples, but the embodiments of the present invention are not limited thereto.

Example 1

In mountain tailings of a polymetallic ore in Weixi of Yunnan, 0.40 percent of Sb, 0.37 percent of Pb, 1.06 percent of S and 0.34g/t of Au. The main metal minerals are pyrite, stibnite and galena; the gangue minerals mainly comprise quartz, calcite, potash feldspar, sericite and the like. The ore structure mainly has a spot structure, a microscopic scale structure, a special-shaped granular structure, a micro-fine granular structure, an inclusion structure and the like.

By utilizing the process, the tailing materials are mixed and scrubbed in the stirring barrel, the stirring concentration is 15 percent (weight ratio), and the stirring strength is 1700 r/min; adding hydrolyzed polyacrylamide and sodium fluoride (weight ratio is 3: 1), the total dosage of the medicament is 16g/t, adopting an ultrafine purification classifier to desliming, the concentration is 10% (weight ratio), and the working pressure is 0.70 MPa; the settled sand enters a hydrocyclone for classification, the underflow of the hydrocyclone is ground by a ball mill, the grinding fineness is 85 percent of minus 0.038 mu m, the overflow of the hydrocyclone is floated, the concentration of the ore pulp is adjusted to 30 percent (weight ratio) before the flotation, the pH is adjusted to 8 by sodium carbonate, the dosage of the sodium carbonate is 800g/t, the dosage of activating agent copper sulfate is 100g/t, 300g/t of lead nitrate, collecting agents are butyl xanthate and butyl ammonium black (weight ratio is 2: 1), the dosage of the collecting agent is 120g/t, a foaming agent is 2# oil (pine oil), the dosage is 40g/t, and the flotation time is 15 min. The process flow is shown in figure 1, and the test results are shown in table 1.

The conventional equipment and combined process flow are adopted and shown in figure 2. The tailing materials are mixed in a stirring barrel, the mixing concentration is 24% (weight ratio), the mixed tailing materials are reselected by a traditional spiral chute, concentrate obtained by reselection is ground to 85% of minus 0.074 mu m, ore pulp obtained after grinding is subjected to flotation by adopting a flow structure of twice roughing, three times of scavenging and three times of concentrating, the dosage of activating agent copper sulfate added in the flotation is 200g/t, 600g/t of lead nitrate, collecting agents are amyl xanthate, butyl xanthate and butyl ammonium black (the weight ratio is 2: 1), the dosage of the collecting agents is 240g/t, foaming agents are 2# oil, the dosage is 80g/t, and the flotation time is 20 min. The process flow is shown in FIG. 2, and the test results are shown in Table 1.

TABLE 1 results of different processes

Unit of injected Au is g/t

Example 2

The tailings of a polymetallic mine in Hunan West Hunan province mainly comprise pyrite, arsenopyrite, stibnite, galena, wheel ore and the like; the gangue minerals are mainly quartz, sericite, calcite, chlorite, kaolin, etc. 0.60% of Sb, 0.51% of Pb, 2.42% of S and 0.36g/t of Au in the ore.

By utilizing the process, the tailing materials are mixed and scrubbed in the stirring barrel, the stirring concentration is 15 percent (weight ratio), and the stirring strength is 2200 r/min; adding hydrolyzed polyacrylamide with the dosage of 20g/t, desliming by adopting an ultrafine purification classifier, wherein the concentration is 12 percent (weight ratio), and the working pressure is 0.75 MPa; the settled sand enters a hydrocyclone for classification, the underflow of the hydrocyclone is ground by a ball mill, the grinding fineness is 82 percent of minus 0.038 mu m, the overflow of the hydrocyclone is floated, the concentration of the ore pulp is adjusted to 33 percent (weight ratio) before the flotation, the pH is adjusted to 7.5 by sodium carbonate, the using amount of the sodium carbonate is 500g/t, the using amount of activating agent copper sulfate is 100g/t, lead nitrate is 260g/t, collecting agents are butyl xanthate and butyl ammonium black (the weight ratio is 3: 1), the using amount of the collecting agent is 150g/t, and the flotation time is 20 min. The process flow is shown in figure 1, and the test results are shown in table 2.

The conventional equipment and combined process flow are adopted and shown in figure 2. The tailing materials are mixed in a stirring barrel, the mixing concentration is 20% (weight ratio), the mixed tailing materials are reselected by a traditional cone concentrator, concentrate obtained by reselection is ground to be 87% with the diameter of-0.074 mu m, ore pulp obtained after grinding is subjected to flotation by adopting a flow structure of twice roughing, three times of scavenging and three times of concentrating, the dosage of activating agent copper sulfate added in the flotation is 250g/t, 550g/t of lead nitrate, collecting agents are amyl xanthate, butyl xanthate and butyl ammonium black (the weight ratio is 3: 2: 1), the dosage of the collecting agent is 246g/t, a foaming agent is 2# oil, the dosage is 85g/t, and the flotation time is 22 min. The process flow is shown in FIG. 2, and the test results are shown in Table 2.

TABLE 2 results of different processes

Unit of injected Au is g/t

From the test results in tables 1 and 2, the grade and recovery rate of the bulk concentrate obtained by the process are far higher than those of the traditional flotation process, particularly the recovery rate of each element is improved by more than 20 percent compared with the traditional combined process, the flotation process is shortened, and the medicament dosage and the power consumption are reduced.

Therefore, after the tailing materials are pretreated, superfine purified and deslimed and a selective ore grinding loop is constructed, the superfine particle over-ground monomer minerals are effectively flocculated to reach the optimal flotation particle size, and the inclusion and the intergrowth are accurately ground, so that the dissociation degree of the minerals is further improved. The measures greatly improve the recovery rate of valuable elements in the tailings, greatly improve the desliming effect and have obvious superiority compared with the traditional process.

Claims

1. A combined process for recovering antimony, lead and gold from polymetallic tailings is characterized by comprising the following steps:

2. The combination process as claimed in claim 1, wherein in the step (1), the concentration after size mixing is 10-20%, and the stirring intensity is 1500-.

3. The combined process according to claim 1, characterized in that in step (1), the flocculant added is hydrolyzed polyacrylamide or polyacrylonitrile, or a mixture of hydrolyzed polyacrylamide and/or polyacrylonitrile and sodium fluoride, in an amount of 5-50 g/t.

4. The combination of claim 1, wherein in the step (2), the pulp conditioning of the ultra-fine purification classifier has a concentration of 5-10% by weight and an operating pressure of 0.65-0.85 Mpa.

5. The combined process according to claim 1, characterized in that in step (3), the classification underflow grind fineness is-0.038 mm 85-90%.

6. The combination process as claimed in claim 1, wherein in the step (3), the flotation regulator is sodium carbonate, the dosage is 500-1000g/t, the pH value is 7-8, the activating agent is one or two of copper sulfate and lead nitrate, the dosage is 100-600g/t, the collecting agent is one or two of butyl sodium xanthate and butyl ammonium nigride, the dosage of the collecting agent is 50-300g/t, and the flotation time is 8-20 min.

7. The combined process of claim 1, wherein in step (3), the flotation process structure comprises one roughing, two scavenging and two concentrating.