Efficient flotation method for medium-low grade and associated difficult-to-utilize bauxite

Abstract

The invention discloses an efficient flotation method for medium-low-grade and co-associated hard-to-utilize bauxite. The efficient flotation method is characterized by comprising the following steps: (1) selecting medium-low-grade co-associated bauxite; (2) crushing the selected bauxite through a crusher; (3) grinding the crushed bauxite through an autogenous mill and a ball mill, checking and screening; (4) mixing and grading the slurry subjected to ore grinding treatment; (5) adding a flotation reagent into the qualified slurry, carrying out flotation through a flotation machine, and carrying out flotation separation to obtain concentrate slurry after the flotation reagent is added; according to the method, bauxite resources are fully and reasonably recycled to the maximum extent, and diaspore, gibbsite, boehmite and soil in the accumulated bauxite are mainly mixed together. In terms of 70% recovery, the ore with the fine fraction smaller than 1 mm can be recovered through flotation, so that the industrial index of the accumulated bauxite and the content of beneficial minerals in the fine fraction slime with the fine fraction smaller than 1 mm of the mud-containing bauxite are comprehensively considered, the boundary ore content can be at least reduced to be below 100 kg / m < 3 >, and the resource reserve of the accumulated bauxite in Guangxi province can be reduced to be below 100 kg / m < 3 >. The number can be multiplied without inputting a large number of exploration projects; the method provided by the invention can reduce the tailing discharge amount, thereby occupying less cultivated land and reducing the tailing discharge cost, can improve the A / S of the wash concentrate, and has obvious economic benefits for improving the productivity, alkali consumption and other indexes of alumina factories.

Description

Technical Field

[0001] The invention relates to the field of bauxite flotation technology, and provides a high-efficiency flotation method for medium- and low-grade and co-existing difficult-to-utilize bauxite. Background Art

[0002] At present, with the development of high-quality bauxite in my country, bauxite resources with high aluminum and high aluminum-silicon ratio are very rare. Most of the bauxite currently processed is coal-based bauxite. The sulfur content of this bauxite is very high, usually high-sulfur bauxite. To develop and utilize this bauxite resource, desulfurization must be carried out to reduce the sulfur content in the mineral to below 0.3%. The factors affecting the desulfurization of high-sulfur bauxite are mainly because the beneficiation fineness of bauxite is very fine, and the sulfur content needs to be reduced to a very low level, which will affect production indicators and other issues. Research and exploration of efficient high-sulfur bauxite desulfurization flotation activators and improving the flotation utilization level of high-sulfur bauxite resources play an important role in comprehensively improving the technical level of the aluminum industry. In the previous high-sulfur bauxite desulfurization technology, copper sulfate or ferrous sulfate is often used to treat the pulp, and collectors and frothers are added for flotation after activation. This activator can only play a good activation role on the mineral in the pulp with little ore mud. In the high-sulfur bauxite pulp with a large amount of mud, the use of a single activator to obtain qualified concentrate indicators will inevitably cause a large amount of useful minerals to float, resulting in a decrease in flotation grade and recovery rate. The present invention has found that in the process of bauxite grinding, due to the serious mudification of bauxite, a large amount of minerals will be adhered to the steel balls during grinding, which greatly reduces the efficiency of grinding and increases energy consumption. In industrial production, it puts a great burden on the subsequent classification process. In the industrial application of bauxite, the aluminum-silicon ratio of bauxite is often required to reach a certain value, or impurities such as titanium, iron, and sulfur need to be removed. Especially in alumina production, the Bayer process with high efficiency, low consumption and simple process generally requires an aluminum-silicon ratio greater than 10. The sintering method for producing alumina requires that the sulfur content of the bauxite ore be less than 0.7%. For medium and low-grade co-existing bauxite, the vast majority of the aluminum-silicon ratios are less than 10, which limits the economic and reasonable industrial application of such bauxite. The existing medium and low-grade co-existing bauxite is difficult to meet the actual use requirements. Summary of the invention

[0003] Purpose of the invention: In order to solve the deficiencies in the prior art, the purpose of the present invention is to provide an efficient flotation method for medium- and low-grade and co-existing difficult-to-utilize bauxite that can be recycled and efficiently recover aluminum resources.

[0004] Technical solution: A high-efficiency flotation method for medium-low-grade and co-existing difficult-to-utilize bauxite, characterized by: (1) selecting medium-low-grade co-existing bauxite; (2) crushing the selected bauxite by a pulverizer; (3) grinding, inspecting and screening the crushed bauxite by an autogenous mill and a ball mill; (4) merging and classifying the slurry after grinding; (5) adding a flotation agent to the qualified slurry and flotating it by a flotation machine, and flotating and separating the concentrate slurry after adding the flotation agent.

[0005] Specifically, in step 3, the autogenous mill is 5500x1800 100t / h, and the ball mill is 3200x4500100t / h.

[0006] Specifically, the grinding concentration is 30-34%, the grinding particle size is -200 mesh, accounting for 80-90%, and the return sand ratio of the grinding machine is 200%, and the overflow concentration of the hydrocyclone in the grinding process is 34-36%. The bottom concentration of the hydrocyclone is 60-70%.

[0007] Specifically, the concentration of the flotation operation in step (5) is 28-30%.

[0008] Specifically, the flotation reagent is composed of xanthate 1.5-2.5 kg / t, sulfuric acid 2-3 kg / t, and 2# oil 100-120 g.

[0009] Specifically, the step 5 includes the following stages: one primary selection operation, one scavenging selection operation, and two concentrating operations. The flotation method can adopt positive flotation or reverse flotation.

[0010] Beneficial effects:

[0011] The advantages of the present invention are:

[0012] The present invention can fully and reasonably recover bauxite resources to the maximum extent. The diaspore, gibbsite, boehmite and soil in the deposited bauxite are mainly mixed together. Only 70% recovery is calculated. Since the ore in the fine particle size less than 1mm can be recovered by flotation, the industrial index of the deposited bauxite should be considered comprehensively with the beneficial mineral content in the fine particle size mud of the mud-containing bauxite less than 1mm. In this way, the boundary mineral content can be at least reduced to below 100kg / m3, so that the reserves of deposited bauxite resources in Guangxi will be doubled without investing in a large number of exploration projects; the amount of tailings discharged can be reduced, thereby occupying less cultivated land and reducing the cost of tailings discharge. The A / S of the washed concentrate can be increased, which will have obvious economic benefits for improving the production capacity and alkali consumption of the alumina plant. Since more bauxite can be recovered by flotation, the amount of ore mining in the mine can be reduced. At the same time, the transportation volume of muddy ore is also greatly reduced, and the cost of the concentrate will be greatly reduced. Since the flotation concentrate has a finer particle size, the grinding cost of the alumina plant can also be saved a lot. It can save water. In a single ore washing process, the water in the overflow of the tailings concentrator and the filtrate of the filter press cannot be directly used. With the process of the present invention, the overflow of the concentrate concentrator and the filtrate of the concentrate filter press can be directly used as flushing water in the ore washing process after being pressurized. DETAILED DESCRIPTION

[0013] The following is a further description in conjunction with specific embodiments of the present invention.

[0014] It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as there is no conflict between them.

[0015] Example 1

[0016] A high-efficiency flotation method for medium-low-grade and co-existing difficult-to-utilize bauxite, characterized by: (1) selecting medium-low-grade co-existing bauxite; (2) crushing the selected bauxite by a pulverizer; (3) grinding, inspecting and screening the crushed bauxite by an autogenous mill and a ball mill; (4) merging and classifying the slurry after grinding; (5) adding a flotation agent to the qualified slurry and flotating it by a flotation machine, and flotating and separating the concentrate slurry after adding the flotation agent.

[0017] Specifically, in step 3, the autogenous mill is 5500x1800 100t / h, and the ball mill is 3200x4500100t / h.

[0018] Specifically, the grinding concentration is 30-34%, the grinding particle size is -200 mesh, accounting for 80-90%, and the return sand ratio of the grinding machine is 200%, and the overflow concentration of the hydrocyclone in the grinding process is 34-36%. The bottom concentration of the hydrocyclone is 60-70%.

[0019] Specifically, the concentration of the flotation operation in step (5) is 28-30%.

[0020] Specifically, the flotation reagent is composed of xanthate 1.5-2.5 kg / t, sulfuric acid 2-3 kg / t, and 2# oil 100-120 g.

[0021] Specifically, step 5 includes the following stages: one preliminary selection operation, one scavenging selection operation, and two concentrating operations. The flotation method can be positive flotation or reverse flotation.

[0022] Example 2

[0023] A high-efficiency flotation method for medium-low-grade and co-existing difficult-to-utilize bauxite, characterized by: (1) selecting medium-low-grade co-existing bauxite; (2) crushing the selected bauxite by a pulverizer; (3) grinding, inspecting and screening the crushed bauxite by an autogenous mill and a ball mill; (4) merging and classifying the slurry after grinding; (5) adding a flotation agent to the qualified slurry and flotating it by a flotation machine, and flotating and separating the concentrate slurry after adding the flotation agent.

[0024] Specifically, in step 3, the autogenous mill is 5500x1800 100t / h, and the ball mill is 3200x4500100t / h.

[0025] Specifically, the grinding concentration is 30-34%, the grinding particle size is -200 mesh, accounting for 80-90%, and the return sand ratio of the grinding machine is 200%, and the overflow concentration of the hydrocyclone in the grinding process is 34-36%. The bottom concentration of the hydrocyclone is 60-70%.

[0026] Specifically, the concentration of the flotation operation in step (5) is 28-30%.

[0027] Specifically, the flotation reagent is composed of xanthate 1.5-2.5 kg / t, sulfuric acid 2-3 kg / t, and 2# oil 100-120 g.

[0028] Specifically, step 5 includes the following stages: one preliminary selection operation, one scavenging selection operation, and two concentrating operations. The flotation method can be positive flotation or reverse flotation.

[0029] Example 3

[0030] A high-efficiency flotation method for medium-low-grade and co-existing difficult-to-utilize bauxite, characterized by: (1) selecting medium-low-grade co-existing bauxite; (2) crushing the selected bauxite by a pulverizer; (3) grinding, inspecting and screening the crushed bauxite by an autogenous mill and a ball mill; (4) merging and classifying the slurry after grinding; (5) adding a flotation agent to the qualified slurry and flotating it by a flotation machine, and flotating and separating the concentrate slurry after adding the flotation agent.

[0031] Specifically, in step 3, the autogenous mill is 5500x1800 100t / h, and the ball mill is 3200x4500100t / h.

[0032] Specifically, the grinding concentration is 30-34%, the grinding particle size is -200 mesh, accounting for 80-90%, and the return sand ratio of the grinding machine is 200%, and the overflow concentration of the hydrocyclone in the grinding process is 34-36%. The bottom concentration of the hydrocyclone is 60-70%.

[0033] Specifically, the concentration of the flotation operation in step (5) is 28-30%.

[0034] Specifically, the flotation reagent is composed of xanthate 1.5-2.5 kg / t, sulfuric acid 2-3 kg / t, and 2# oil 100-120 g.

[0035] Specifically, the step 5 includes the following stages: one primary selection operation, one scavenging selection operation, and two concentrating operations. The flotation method can adopt positive flotation or reverse flotation.

Claims

1. An efficient flotation method for medium-low grade and associated difficult-to-utilize bauxite, characterized by: (1) Select medium- and low-grade co-existing bauxite; (2) Use a pulverizer to crush the selected bauxite; (3) Use an autogenous mill and a ball mill to grind, inspect and screen the crushed bauxite; (4) Combine and classify the slurry after grinding; (5) Add a flotation agent to the qualified slurry and use a flotation machine to float it, and then float and separate the concentrate slurry after adding the flotation agent.

2. The high-efficiency flotation method for low- and medium-grade bauxite and associated difficult-to-utilize bauxite according to claim 1, characterized in that: In step 3, the autogenous mill is 5500x1800 100t / h, and the ball mill is 3200x4500100t / h.

3. The method for high-efficiency flotation of low-grade and co-existing difficult-to-utilize bauxite according to claim 1, characterized in that: The grinding concentration is 30-34%, the grinding particle size is -200 mesh, accounting for 80-90%, and the return sand ratio of the grinding machine is 200%, and the overflow concentration of the hydrocyclone in the grinding process is 34-36%. The bottom concentration of the hydrocyclone is 60-70%.

4. The high-efficiency flotation method for low- and medium-grade bauxite and associated difficult-to-utilize bauxite according to claim 1, characterized in that: The concentration of the flotation operation in step (5) is 28-30%.

5. The method for efficient flotation of low-grade and co-existing difficult-to-utilize bauxite according to claim 1, characterized in that: The flotation reagent is composed of xanthate 1.5-2.5kg / t, sulfuric acid 2-3kg / t, and 2# oil 100-120g.

6. The method for high-efficiency flotation of low- and medium-grade bauxite and associated bauxite that is difficult to utilize according to claim 1, characterized in that: The step 5 includes the following stages: one primary selection operation, one scavenging selection operation, and two concentrating operations. The flotation method can adopt positive flotation or reverse flotation.