CN111298978B

CN111298978B - Method for flotation of lepidolite without desliming

Info

Publication number: CN111298978B
Application number: CN202010130705.0A
Authority: CN
Inventors: 欧乐明; 张政军; 周浩
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2020-02-28
Filing date: 2020-02-28
Publication date: 2022-03-18
Anticipated expiration: 2040-02-28
Also published as: CN111298978A

Abstract

The invention discloses a method for floating lepidolite without desliming, which comprises the steps of coarse grinding, rough concentration, scavenging, fine concentration, middling recleaning and regrinding, and specifically comprises the following steps: mixing lepidolite raw ore and sodium hexametaphosphate, carrying out ball milling to obtain rough grinding ore, merging foam products obtained by two scavenging into rough concentrate, carrying out first concentration operation, mixing middlings obtained by three concentration operations, carrying out middling recleaning operation, carrying out regrinding operation on the concentrate obtained by the middling recleaning operation, and returning the reground products to the rough concentration operation or the first refining operation. According to the method, sodium hexametaphosphate is used as a flotation regulator, the ceramic balls are used as an ore grinding medium, and the steps of middling recleaning and regrinding are added, so that the harmful influence of fine mud on flotation can be obviously inhibited, and therefore, the step of desliming is not required before flotation, and the method has the advantages of high reaction efficiency, simple steps, high recovery rate and the like.

Description

Method for flotation of lepidolite without desliming

Technical Field

The invention relates to the field of mineral separation, in particular to a method for flotation of lepidolite without desliming.

Background

Lithium is a soft silvery white metal, the lightest basic metal. Lithium compounds such as lithium carbonate, lithium hydroxide and lithium bromide are widely used in the manufacture of glass, ceramics, lubricating oils and the like, and other fields of application include the production of aluminum, catalysts for the pharmaceutical and rubber industries, and air conditioning and dehumidification systems. In recent years, the application of lithium ion technology to electric vehicles has made the demand for lithium minerals in industry increasingly greater. The sources of lithium are two: brine and lithium ore. Global lithium yields of over 60% are derived from brine, others from lithium ore. In China, lithium ore resources are abundant, but the grades are generally low and the ore embedding relationship is complex, so that the utilization rate is not high, and the resource advantages are not converted into economic advantages.

Lepidolite is a mica with a complex and variable composition, in which the content of lithium oxide varies between 3.0% and 7.7%. Lepidolite is often associated with silicate minerals of calcite, feldspar, and quartz. The flotation method is the most commonly used method for recovering the fine-grained embedded lepidolite, and the lepidolite is in a single-piece shape and is difficult to grind, so the concentrate grade of the lepidolite is usually below 3 percent, and the recovery rate is not more than 70 percent. Meanwhile, the ore grinding time is too long, so that fine ore is easy to argillization, the separation effect of the lepidolite is poor, and the industrial desliming operation has to be added to remove the fine mud in advance, so that the cost is increased, and the loss of the lepidolite in the separation process is increased.

At present, the research on the lepidolite flotation process in China is less, the research on the lepidolite flotation process is an important part for realizing the high-efficiency recovery of lithium resources and maintaining the sustainable development, and meanwhile, a new method which does not need to desliming and can improve the lepidolite concentrate flotation recovery rate through a re-selection regrinding process is needed to be developed.

Disclosure of Invention

In order to solve the problems, the invention aims to provide a novel lepidolite flotation method which does not need to be deslimed and has high recovery efficiency aiming at the defects of the prior art.

In order to achieve the aim, the invention provides a method for flotation of lepidolite without desliming, which comprises the following steps:

s1, coarse grinding: mixing lepidolite raw ore and sodium hexametaphosphate, and then carrying out ball milling to obtain coarse grinding ore;

s2, rough selection: adding a collecting agent into the rough concentrate, fully stirring, and then carrying out inflation and foam scraping to obtain rough concentrate and rough tailings;

s3, scavenging: adding a collecting agent into the roughed tailings, fully stirring, and then inflating and scraping to obtain scavenging foam products and tailings I;

s4, selecting: and merging the scavenging foam product into the rough concentrate, adding sodium hexametaphosphate, fully stirring, and performing inflation foam scraping to obtain lepidolite concentrate and middlings.

The method for flotation of lepidolite without desliming further comprises the following steps:

s5, middling recleaning: adding a collecting agent into the middlings, fully stirring, and then carrying out inflation and foam scraping to obtain middlings recleaning foam and tailings II;

s6, regrinding: and performing ball milling on the middling recleaning foam to obtain a reground product, and performing circulating treatment on the reground product according to the steps of S2-S4 to finally obtain lepidolite concentrate.

In the method for floating lepidolite without separating mud, the ball milling time in S6 is 8min, and the ball milling medium is ceramic balls.

s6, regrinding: and performing ball milling on the middling recleaning foam to obtain a reground product, and performing circulating treatment on the reground product according to the step of S4 to finally obtain lepidolite concentrate.

The method for flotation of lepidolite without desliming further comprises the step of carrying out Li flotation on the lepidolite raw ore₂The O grade is 0.75 percent, and the content of minus 100 meshes is 70-80 percent.

In the above method for flotation of lepidolite without desliming, in S1, the addition amount of sodium hexametaphosphate is 600g/t, the ball milling time is 3 minutes, the ball milling medium is ceramic balls, and the content of coarse grinding ore in a 100-mesh size is 83%.

In the above method for flotation of lepidolite without separation of mud, S3 specifically includes:

s3-1, adding a collecting agent into the roughed tailings, fully stirring, and then inflating and scraping to obtain scavenging foam products I and scavenging tailings;

and S3-2, merging the obtained scavenging foam product I into the rough concentrate, adding a collecting agent into the scavenging tailings, fully stirring, and then carrying out air inflation and foam scraping to obtain a scavenging foam product II and a tailing I.

In the above method for flotation of lepidolite without separation of mud, S4 specifically includes:

s4-1, merging the scavenged foam product into the rough concentrate, adding sodium hexametaphosphate, stirring fully, and then starting to inflate and scrape the foam to obtain a refined foam product;

s4-2, selecting a first foam product, adding sodium hexametaphosphate, stirring fully, and then starting to inflate and scrape foam to obtain a second foam product;

and S4-3, adding sodium hexametaphosphate into the fine-selected bi-foam product, fully stirring, and then starting to inflate and scrape the foam to obtain a concentrate product.

In the method for flotation of lepidolite without separation of mud, the addition amount of sodium hexametaphosphate in the S4-1 is 200 g/t;

and/or in the S4-2, the addition amount of the sodium hexametaphosphate is 150 g/t;

and/or in the S4-3, the addition amount of the sodium hexametaphosphate is 100 g/t.

In the method for flotation of lepidolite without desliming, the collector is neutral # 2.

Compared with the prior art, the invention has the following beneficial effects:

(1) the invention provides a method for floating lepidolite without desliming, which adopts sodium hexametaphosphate as a flotation regulator and can obviously inhibit fine mud from floating upwards, so that a desliming step is not needed before flotation. The sodium hexametaphosphate has dispersing effect, and can inhibit fine mud covering phenomenon. Specifically, sodium hexametaphosphate can change the electrical property of the surface of the mineral by being adsorbed on the surface of the mineral, so that the electrostatic adsorption between fine mud and the mineral is inhibited, and the entrainment floating amount is reduced. In the coarse grinding stage, the addition amount of the sodium hexametaphosphate is 600g/t, and in the fine selection stage, the addition amounts of the sodium hexametaphosphate are 200g/t, 150g/t and 100g/t in sequence. Addition amount of sodium hexametaphosphate to concentrate Li₂The grade and recovery rate of O have certain influence, which is reflected in that the using amount of sodium hexametaphosphate is increased and Li of concentrate is₂The O grade is increased and the recovery rate is reduced. Based on the particle size characteristics of the lepidolite ore used in the test, better tailing running indexes and ore concentrate indexes can be obtained by performing a flotation test under the condition of the using amount of sodium hexametaphosphate used in the test.

(2) The invention provides a method for floating lepidolite without desliming, wherein ceramic balls are used as ore grinding media in the rough grinding and regrinding operation of lepidolite, and the characteristics of the ceramic balls ensure that the particle size distribution of an ore grinding product is uniform, so that the too high amount of rough mud caused by over grinding is avoided. And because no iron ion pollution exists, the floating amount of the gangue such as quartz, calcite and the like can be obviously reduced. The regrinding time is 8 minutes, coarse particle flaky mica can be effectively ground, and the regrinding product has a-200 mesh content of over 60 percent.

(3) The invention provides a method for flotation of lepidolite without desliming, wherein the grade of concentrate product Li2O reaches 3.21%, the recovery rate reaches 83.5%, and compared with the existing flotation method, the concentrate grade of lepidolite is usually below 3%, the recovery rate does not exceed 70%, and the effect is obviously improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a flow chart of the lepidolite flotation process of the present invention in example 1 of the present invention.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention. Modifications or substitutions to methods, procedures, or conditions of the invention may be made without departing from the spirit and scope of the invention.

Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art; all reagents used in the examples are commercially available unless otherwise specified.

The percentage "%" referred to in the present invention means mass% unless otherwise specified; but the percentage of the solution, unless otherwise specified, refers to the grams of solute contained in 100ml of the solution.

The weight parts in the invention can be the weight units known in the art such as mu g, mg, g, kg, and the like, and can also be multiples thereof, such as 1/10, 1/100, 10, 100, and the like.

The neutral collector 2# is provided for the situation of Yichun Jima in Jiangxi.

Example 1:

the method for flotation of lepidolite without desliming comprises the following steps of:

(1) coarse grinding: selecting lepidolite ore in Yichun in Jiangxi, wherein the gangue mainly comprises quartz, feldspar, calcite and the like, and the raw ore Li₂The O grade is 0.75 percent, and the content of minus 100 meshes is 70-80 percent. The raw ore is added with 600g/t of sodium hexametaphosphate in a ball mill, and the grinding time is 3 minutes, so as to obtain coarse ground ore, wherein the content of minus 100 meshes is 83 percent.

(2) Primary rough selection:

2.1, adding the coarse ores into a mechanical stirring type flotation machine, adjusting the concentration of the ore pulp to be about 30%, and fully stirring for 3 min.

2.2, adding 500g/t of neutral 2#, fully stirring, then starting to inflate and scrape bubbles to obtain rough concentrate and tailings, and continuously carrying out scavenging operation on tailing products in the tank.

(3) Secondary scavenging:

3.1, scavenging one: adding the tailing product into 250g/t neutral 2#, fully stirring, then starting inflating and scraping bubbles to obtain a scavenging foam product I, and continuously scavenging the scavenging tailings in the tank.

3.2, scavenging two: merging the obtained scavenging foam product I into the rough concentrate, adding 125g/t neutral 2# into scavenging tailings, fully stirring, then starting inflating and scraping to obtain a scavenging foam product II, merging the scavenging foam product II into the rough concentrate, and taking the tailing I in the tank.

(4) Tertiary concentration

4.1, selecting one: feeding the rough concentrate obtained in the step (3) into a concentration flotation operation, which specifically comprises the following steps: adding 200g/t sodium hexametaphosphate, fully stirring, and then starting to inflate and scrape bubbles to obtain a fine selection foam product and a middling product.

4.2, selecting two: feeding the first-choice foam product into a second-choice flotation operation, which comprises the following steps: adding 150g/t of sodium hexametaphosphate, fully stirring, and then starting to inflate and scrape bubbles to obtain a second selected foam product and a second middling product. And merging the obtained middling two products into the middling one product.

4.3, selecting three: feeding the selected second-foam product into a selected third flotation operation, which specifically comprises the following steps: adding 100g/t of sodium hexametaphosphate, fully stirring, and then starting to inflate and scrape bubbles to obtain a concentrate product and a middling product. And merging the obtained middling three products into the middling one product so as to obtain a middling mixed product.

(5) And (3) middling recleaning operation:

5.1, mixing the middling mixed product obtained in the step (4) and then feeding the mixture to middling recleaning operation, specifically comprising the following steps: adding 125g/t of neutral 2# into the middling mixed product, fully stirring, and performing air flotation to obtain a middling recleaning foam product, wherein the tailing product is obtained in a tank;

(6) regrinding

6.1, feeding the middling recleaning foam product obtained in the step (5) into a ceramic ball regrinding operation, wherein the regrinding time is 8 minutes to obtain a regrinding product, returning the regrinding product to the rough concentration operation, and continuously performing circulating treatment according to the steps of rough concentration, scavenging, fine concentration, middling recleaning and regrinding to finally obtain lepidolite concentrate.

Li₂The O grade is 0.34 percent, and the concentrate product Li₂The O grade was 3.21% and the recovery rate was 83.5%.

Example 2:

(2) Primary rough selection:

(3) Secondary scavenging:

(4) Tertiary concentration

(5) And (3) middling recleaning operation:

(6) regrinding

6.1, feeding the middling recleaning foam product obtained in the step 5 into a ceramic ball regrinding operation, wherein the regrinding time is 8 minutes to obtain a regrinding product, returning the regrinding product to the concentration operation, and continuously performing circulating treatment according to the steps of first concentration, second concentration, third concentration, middling recleaning and regrinding to finally obtain lepidolite concentrate.

The grade of the finally obtained concentrate product can also reach about 3 percent, and the recovery rate is more than 75 percent.

Example 3:

method for flotation of lepidolite without desliming by respectively inspecting addition amount of sodium hexametaphosphate in rough concentration stage to concentrate Li₂The effect of O grade and recovery, the amount of sodium hexametaphosphate added was as shown in Table 1, and the rest of the procedure was the same as in example 1.

Table 1: result table of influence of sodium hexametaphosphate content in rough concentration stage on flotation effect

The dosage of the roughly selected sodium hexametaphosphate	Concentrate Li₂Grade of O (%)	Concentrate Li₂O recovery (%)
			0	2.26	54.3
400	2.84	84.1
			600	3.21	83.5
800	3.35	77.0

Slave watchThe results of 1 show that: under the condition of roughing without adding sodium hexametaphosphate, concentrate Li obtained by three-stage concentration₂The grade and recovery rate of O are both low, which indicates that the fine mud deteriorates the flotation effect, and the collecting efficiency of the collecting agent on the lepidolite is not high under the condition of the ore pulp; the addition of sodium hexametaphosphate can obviously reduce the influence of fine mud on flotation and improve Li of concentrate₂The grade and the recovery rate of O, and Li of the concentrate ore along with the increase of the using amount of the rough concentration sodium hexametaphosphate₂O tends to increase in grade and decrease in recovery.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. The method for flotation of lepidolite without desliming is characterized by comprising the following steps:

s1, coarse grinding: mixing lepidolite raw ore and 600g/t sodium hexametaphosphate, and then carrying out ball milling to obtain coarse grinding ore; li in the lepidolite raw ore₂The O grade is 0.75%, the-100-mesh content is 70-80%, the ball milling time is 3 minutes, the ball milling medium is ceramic balls, and the coarse grinding ore-100-mesh content is 83%;

s3, scavenging: adding a collecting agent into the roughed tailings, fully stirring, and then inflating and scraping to obtain scavenging foam products I and scavenging tailings; merging the obtained scavenging foam product I into rough concentrate, adding a collecting agent into scavenging tailings, fully stirring, and then carrying out inflation foam scraping to obtain a scavenging foam product II and a scavenging foam product I;

s4, selecting: merging the scavenging foam product I and the scavenging foam product II into rough concentrate, adding 200g/t of sodium hexametaphosphate, stirring fully, and then starting inflation and foam scraping to obtain a first concentration foam product and a first middling product; adding 150g/t of sodium hexametaphosphate into the first foam product, stirring fully, then starting inflation and foam scraping to obtain a second foam product and a second middling product, and merging the second middling product into the first middling product; adding 100g/t of sodium hexametaphosphate into the second-stage foam product, fully stirring, and then starting inflation and foam scraping to obtain a concentrate product and a third-stage mineral product; merging the middling product III into the middling product I to obtain a middling mixed product;

s5, middling recleaning: adding the middling mixed product into a collecting agent, fully stirring, and then carrying out inflation and foam scraping to obtain middling recleaning foam and tailings II;

s6, regrinding: and performing ball milling on the middling recleaning foam to obtain a reground product, performing circulating treatment on the reground product according to the steps of S2-S4 to finally obtain lepidolite concentrate, wherein the regrind time is 8min, and the reground medium is ceramic balls.

2. The method for flotation of lepidolite without separation from mud according to claim 1, wherein the step S6 is: