CN111992336B

CN111992336B - Selective desorption and recycling method for mineral surface medicament

Info

Publication number: CN111992336B
Application number: CN202010833845.4A
Authority: CN
Inventors: 孙伟; 王建军; 高志勇; 胡岳华; 陶黎明; 江哲伊; 汪聪
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2020-08-18
Filing date: 2020-08-18
Publication date: 2021-05-11
Anticipated expiration: 2040-08-18
Also published as: CN111992336A

Abstract

The invention belongs to the technical field of mineral flotation and reagent recycling, and particularly discloses a selective desorption method of a mineral surface reagent, which comprises the steps of adding a desorbent into ore pulp of minerals with chelating reagents on the surfaces, desorbing the minerals and the reagents under the assistance of high-speed stirring, and then carrying out solid-liquid separation to obtain the minerals and the recycled reagents; the medicament comprises a chelating collector; the desorbent is acid or alkali; and the dosage of the desorbent is 30-100 g/t. The invention also provides a method for recycling the recovered medicament. According to the technical scheme, the selective desorption separation of minerals and medicaments can be improved and realized by utilizing the chemical-physical synergistic effect of the desorbent and the high-speed stirring, so that the desorbent is favorable for avoiding the damage of the medicaments and the loss of the minerals, the medicaments on the surfaces of the minerals can be effectively recovered, the subsequent mineral concentrate smelting process is improved, and the corresponding water treatment cost is reduced.

Description

Selective desorption and recycling method for mineral surface medicament

Technical Field

The invention belongs to the technical field of mineral flotation and hydrometallurgy, and particularly relates to a method capable of selectively desorbing beneficial agents on the surface of a mineral, which comprises a desorption method and a recycling method.

Background

In the field of flotation, the types of mineral collectors are mainly divided into a fatty acid system and a chelating agent system. Fatty acid systems have low agent cost but poor selectivity, and chelant systems have high agent cost but good selectivity. However, the fatty acid system is usually accompanied by the use of a large amount of inhibitors, such as water glass, etc., to improve the grade of the target mineral concentrate, which leads to tailing settlement and tail water recycling difficulties. Along with the improvement of the requirement of environmental protection and the higher requirement of the grade of some mineral concentrate products, such as tungsten, tin, rare earth, rutile ore and the like, the chelating agent system medicament is more and more valued and widely used. However, the medicament cost of the chelating agent system is generally higher, which leads to the increase of the production cost, and the popularization and the application of the chelating agent system are also influenced. Therefore, finding a technique to reduce the cost of using chelating agents is of great importance for further applications of chelating agents.

A large amount of beneficial agents, particularly collecting agents, remain on the surface of the mineral concentrate obtained after flotation. However, most mineral concentrates are smelted directly and no further treatment is currently available. Not only does this waste a large amount of valuable beneficial agent, but also because the residual agent on the surface of mineral concentrate leads to the difficulty of smelting, has also increased the waste water treatment cost after smelting simultaneously.

Disclosure of Invention

The invention aims to provide a method for selectively desorbing a mineral surface agent, which aims to solve the problems of high use cost, low efficiency and high wastewater treatment cost of smelting enterprises of chelating agents.

A second object of the present invention is to provide a method for recycling chemicals on the surface of minerals, which is capable of separating chemicals from the minerals to be floated and recycling the chemicals.

The desorption of minerals and agents in flotation concentrates still belongs to the blank of the industry. The invention aims to realize desorption and separation of minerals and agents in flotation concentrate for the first time, however, researches find that the selectivity of agent desorption needs to be properly solved for successfully realizing agent desorption, and the technical problems of agent inactivation, leaching loss of minerals and the like are avoided. In order to solve the technical problem, the inventor of the invention provides the following technical scheme through intensive research:

a selective desorption method of mineral surface agents is characterized in that a desorbent is added into ore pulp of minerals (namely concentrate obtained by agent flotation, the invention is also called flotation concentrate for short) with chelating agents on the surface, the minerals and the agents are desorbed under the assistance of high-speed stirring, and then the minerals and the recovered agents are obtained through solid-liquid separation;

the chelating agent (also called agent for short in the invention) comprises a chelating collector;

the desorbent is acid or alkali; and the dosage of the desorbent is 30-100 g/t.

According to the technical scheme of the invention, the selective desorption and separation of minerals and medicaments can be improved and realized by utilizing the chemical-physical synergistic effect of the desorbent and the high-speed collision (high-speed stirring), and the desorbent is also favorable for avoiding the damage of the medicaments and the loss of the minerals and can effectively recover the medicaments on the surfaces of the minerals. Based on the technical scheme of the invention, the selective desorption of the mineral surface medicament can be realized for the first time, and the technical blank of the industry is filled.

The mineral with the chelating agent on the surface is concentrate obtained by flotation of a chelating collecting agent.

In the invention, the chelating agent is at least one of hydroximic acid collecting agent, organic phosphonic acid collecting agent and hydroxylamine collecting agent.

For example, the chelating collector is one or more of benzohydroxamic acid, salicylhydroxamic acid, octylhydroxamic acid, styrenephosphonic acid, and ammonium N-nitrosophenylhydroxylamine.

The mineral species of the invention include one or more of tungsten ore, tin ore, rare earth ore, rutile and ilmenite.

Preferably, the acid is one which ionizes H in water⁺The substance of (1); preferably at least one of hydrochloric acid and sulfuric acid;

preferably, the base is one which ionizes OH in water^-The substance of (1); preferably at least one of hydroxides and carbonates of alkali metals.

The research of the invention also finds that the physical and chemical synergy of the desorbent and the high-speed collision is beneficial to improving the separation selectivity of minerals and medicaments. Research also finds that the further control of conditions such as ore pulp concentration, desorbent dosage, high-speed collision stirring speed and the like in the treatment process is beneficial to further improving the separation selectivity of minerals and medicaments, improving the medicament recovery rate, avoiding medicament inactivation and avoiding mineral loss.

In the invention, the dosage of the desorbent is based on the mineral flotation raw ore. The flotation raw ore refers to raw ore before reaction with the chelating agent. Preferably, the dosage of the desorbent is 60-80 g/t.

Preferably, the concentration of the ore pulp is 10-70%, preferably 15-60%; further preferably 20-40%; more preferably 25 to 35%.

In the invention, the high-speed stirring speed is 2000-3000 r/min; further preferably 2500 to 2800 r/min.

In the invention, the temperature in the desorption process is room temperature, and preferably 5-40 ℃.

The desorption time is preferably 10-30 min; more preferably 15 to 25 min.

Preferably, after the analysis, solid-liquid separation is performed, and the analyzed minerals and the recovered chemical are recovered.

Preferably, the solid-liquid separation means is centrifugation, and the rotation speed of the centrifugation is 800-1400 r/min; further preferably 1000 to 1200 r/min.

The invention also provides a method for recycling the mineral surface medicament, which adopts the desorption method to obtain the recycled medicament; and recycling the recovered chemicals to the flotation of the next batch of minerals.

The recycling method can effectively recycle beneficial agents on the surface of the floated minerals, and reduces the difficulty of subsequent smelting of the minerals and the environmental protection pressure. Moreover, the research also unexpectedly finds that the recycling of the recovered medicament can further improve the flotation effect, such as the recovery rate and/or the grade of the flotation, on the premise of reducing new medicaments and the use amount.

In the invention, the recycling method mixes the recovered chemical with the reduced new chemical and is used for the flotation of the minerals of the next batch; the decrement proportion of the new medicament is 15-50%. The decrement proportion is 15-50% decrement based on the original planned dosage. In the present invention, the originally planned amount refers to the amount of the flotation reagent used to obtain the mineral to be recovered. More preferably, the recycling of the recovered drug is such that the amount of the new drug is reduced by 20 to 40%.

According to the technical scheme, the recycling treatment can reduce the dosage of the medicament, and can also improve the performances such as flotation recovery rate and/or grade unexpectedly, so that the performances are improved on the premise of really saving resources.

Advantageous effects

(1) The selective desorption and the recycling of the mineral surface medicament are realized for the first time.

In the invention, the potential of the surface of the mineral and the structure of the adsorbed medicament are modified by the desorbent and are further cooperated with high-speed stirring, so that the high-selectivity separation of the mineral and the medicament chelated on the surface can be realized based on the physical and chemical synergistic action, and moreover, the inactivation of the medicament and the loss of the mineral are also avoided. The recycled medicament is further recycled, so that the flotation performance can be improved unexpectedly by matching with the recycled medicament under the condition of reducing new medicament.

(2) The desorption method is simple and efficient; the recycling of the desorption agent is beneficial to reducing the cost of the flotation agent and the treatment cost of the smelting water, and simultaneously improving the smelting process.

The invention provides a simple and efficient selective desorption technology for mineral surface agents, and the desorbed agents are recycled for the flotation process, so that the sustainable use technology of agent adsorption-desorption-reuse-adsorption is realized. The technology not only realizes the sustainable recycling of expensive chelating agents, reduces the cost of flotation agents, but also reduces the wastewater treatment cost and the smelting process in the smelting process (the less the agent residue on the surface of the concentrate affects the smelting process), protects the ecological environment, realizes the win-win situation of mineral processing enterprises and smelting enterprises, and ensures the economic benefit and sustainable development of the enterprises.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, it is obvious that the drawings described below are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:

FIG. 1 is a graph showing the effect of desorption of benzohydroxamic acid; from left to right, comparative example 1, comparative example 2, example 5, example 6 and example 1 were followed.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.

In the following cases, the temperature of the flotation process was room temperature (15-35 ℃) unless otherwise stated.

Example 1

Performing tungsten flotation on sulfur-selecting tailings (tungsten raw ore) taken from Chenzhou of Hunan province, wherein WO₃The grade is 0.40%, the gangue mainly comprises garnet and calcite, the dosage of the roughing collector is 600g/t lead nitrate, 500g/t benzohydroxamic acid, the flotation pH of the ore pulp is 9.0, the flotation time is 6min, the stirring speed of the flotation machine is 2000r/min, and the flotation result (without concentrated solution) is shown in table 1. Then, the tungsten concentrate ore pulp is put into a stirrer, the concentration of the ore pulp is adjusted to be 25%, the stirring speed is 2700r/min, then, 60g/t of sodium hydroxide serving as a desorption agent (aiming at tungsten raw ore) is added, after stirring is carried out for 15min, the ore pulp immediately enters a centrifugal machine for concentration, and centrifugal concentrated solution containing a large amount of beneficial collecting agents returns to the original flotation flow for use. Color concentrateThe color is shown in FIG. 1. After the concentrated solution is added, the dosage of the lead nitrate and the dosage of the benzohydroxamic acid are respectively reduced to 450g/t and 350g/t (30 percent of reduction compared with the original planned medicament), other flotation conditions are consistent, and the flotation results (concentrated solution, namely recycled medicament groups) are shown in Table 1. The results in table 1 show that, after the concentrated solution of the tungsten concentrate surface desorption agent is added, the grade of the tungsten rough concentrate is slightly increased, but the recovery rate is greatly increased, and meanwhile, the use amounts of the collecting agents of lead nitrate and benzohydroxamic acid are respectively reduced by 25.00% and 30.00%, so that the concentrated solution has a better effect on the grade and/or recovery rate, and the indication is obvious in the treatment technical effect on the concentrate.

TABLE 1

Example 2

Tin ore (raw tin ore) taken from a certain old dressing plant in Yunnan is subjected to flotation, wherein the grade of Sn is 0.55 percent, gangue mainly comprises quartz and feldspar, the dosage of a roughing collector is 500g/t of lead nitrate, 700g/t of benzohydroxamic acid, the dosage of inhibitor water glass is 300g/t, the pH value of ore pulp flotation is 8.0, 40g/t of No. 2 oil, the speed is 2000r/min, and the flotation result (without concentrated solution) is shown in Table 2. Then, the tin concentrate ore pulp is put into a stirrer, the concentration of the ore pulp is adjusted to be 30%, the stirring speed is 2800r/min, then, 80g/t (aiming at tin raw ore) of desorbent hydrochloric acid is added, after stirring is carried out for 20min, the ore pulp immediately enters a centrifugal machine for concentration, and centrifugal concentrated solution containing a large amount of beneficial collecting agents returns to the original flotation process for use. After the concentrated solution is added, the use amounts of lead nitrate and benzohydroxamic acid are respectively reduced to 400g/t and 550g/t, other flotation conditions are consistent, and flotation results (with the concentrated solution) are shown in Table 2. The results in table 2 show that after the concentrated solution of the tin concentrate surface desorption agent is added, the grade and the recovery rate of the tin concentrate are greatly increased, and meanwhile, the use amounts of the collecting agents of lead nitrate and benzohydroxamic acid are respectively reduced by 20.00% and 21.43%, and the effect is remarkable.

TABLE 2

Example 3

The method comprises the steps of carrying out flotation on rare earth ore (fluorine-carbon cerium raw ore) taken from a certain Sichuan crown Ning selection plant, wherein the REO grade is 3.06%, gangue mainly comprises feldspar, quartz, barite and fluorite, the dosage of roughing inhibitor water glass is 3000g/t, the dosage of collecting agent salicylhydroxamic acid is 4000g/t, No. 2 oil is 40g/t, the speed is 2000r/min, and the flotation result (without concentrated solution) is shown in Table 3. Then, the rare earth concentrate ore pulp is put into a stirrer, the concentration of the ore pulp is adjusted to be 35%, the stirring speed is 2600r/min, then 80g/t of sodium hydroxide (aiming at fluorine-carbon cerium raw ore) as a desorption agent is added, the ore pulp is stirred for 25min, then the ore pulp immediately enters a centrifugal machine for concentration, and centrifugal concentrated solution containing a large amount of beneficial collecting agents is returned to the original flotation process for use. After the concentrated solution is added, the dosage of the salicylhydroxamic acid is reduced to 3000g/t, other flotation conditions are consistent, and the flotation results (with the concentrated solution) are shown in table 3. From the results in table 3, it can be seen that, after the concentrated solution of the rare earth concentrate surface desorption agent is added, the grade and the recovery rate of the rare earth concentrate are greatly increased, particularly the recovery rate is increased, and meanwhile, the use amount of the collecting agent salicylhydroxamic acid is reduced by 25.00%, and the effect is remarkable.

TABLE 3

Example 4

Subjecting rutile ore (rutile crude ore) from certain selection factory of Ziyang of Hubei to flotation, wherein TiO is₂The grade is 3.19%, the gangue is mainly hornblende, garnet, chlorite, celadon, feldspar and the like, the dosage of roughing inhibitors sodium hexametaphosphate and water glass is 1000 g/t and 300g/t respectively, the dosage of collecting agents styrene phosphonic acid is 800g/t, the dosage of lead nitrate is 200g/t, No. 2 oil is 10g/t, the speed is 2000r/min, and the flotation result (without concentrated solution) is shown in a table 4. Then, willThe rutile concentrate ore pulp is put into a stirrer, the concentration of the ore pulp is adjusted to be 30%, the stirring speed is 2700r/min, then desorption agent sulfuric acid is added for 60g/t (aiming at rutile raw ore), after stirring for 20min, the ore pulp immediately enters a centrifugal machine for concentration, and centrifugal concentrated solution containing a large amount of beneficial collecting agents is returned to the original flotation process for use. After the concentrated solution was added, the amount of styrene phosphonic acid was reduced to 500g/t, and other flotation conditions were consistent, and the flotation results (with concentrated solution) are shown in Table 4. The results in table 4 show that after the concentrated solution of the rutile concentrate surface desorption agent is added, the grade of the rutile concentrate is slightly increased, but the recovery rate is greatly increased, and meanwhile, the dosage of the collecting agent styrene phosphonic acid is reduced by 37.50%, and the effect is remarkable.

TABLE 4

Comparative example 1

The amount of sodium hydroxide as a desorbent was 0g/t, the rest was the same as in example 1, and the color of the concentrate after desorption was shown in FIG. 1, and the flotation results are shown in Table 5.

Comparative example 2

The amount of sodium hydroxide as a desorbent was 15g/t, the rest was the same as in example 1, and the color of the concentrate after desorption was shown in FIG. 1, and the flotation results are shown in Table 5.

Example 5

The amount of sodium hydroxide as a desorbent was 30g/t, the rest was the same as in example 1, and the color of the concentrate after desorption was shown in FIG. 1, and the flotation results are shown in Table 5.

Example 6

The amount of sodium hydroxide as a desorbent was 90g/t, the rest was the same as in example 1, and the color of the concentrate after desorption was shown in FIG. 1, and the flotation results are shown in Table 5.

The desorption pictures of comparative examples 1-2, examples 5 and 6 and example 1 are shown in fig. 1, and it can be seen from the figure that the color of the concentrate after the surface desorption of the concentrate is gradually deepened with the increase of the dosage of the desorbent, the color tends to be stable after a certain dosage is reached (60g/t, example 1), the COD value also tends to be stable, the grade and the recovery rate of the tungsten concentrate also gradually increase and then stabilize, which indicates that the increase of the dosage of the desorbent is helpful for improving the desorption amount of the beneficial agent on the surface of the mineral, namely the dosage of the desorbent is an important influence factor of the invention.

TABLE 5 COD values of concentrates and flotation results at different desorbent dosages

Example 7

The concentration of the slurry in the concentrate desorption process was 10%, the other steps were the same as in example 2, the grade Sn of the obtained tin concentrate was 4.02%, and the recovery rate was 65.35%.

Example 8

The concentration of the ore pulp in the desorption process of the concentrate is 70 percent, the rest is the same as that of the example 2, the grade Sn of the obtained tin concentrate is 3.68 percent, and the recovery rate is 68.72 percent.

Comparative example 3

The stirring speed in the concentrate desorption process is 1000r/min, the rest is the same as that in the example 2, the grade Sn of the obtained tin concentrate is 3.15 percent, and the recovery rate is 61.10 percent.

Compared with the embodiment 2, the embodiments 7-8 and the comparative example 3 show that both too low and too high concentration of the ore pulp during desorption have influence on agent desorption, and further the flotation result is poor; meanwhile, the stirring speed of ore pulp in the desorption process can directly influence the desorption effect of the medicament, and the stirring speed is too low, so that the desorption effect is influenced, and the subsequent flotation index is deteriorated.

In conclusion, by adopting the method provided by the invention, based on the physical and chemical double synergistic effects of the desorbent and the high-speed stirring, the recovery of the chelating agent on the surface of the concentrate can be effectively realized, in addition, the rotating speed of the desorbent and the high-speed stirring and the concentration of the ore pulp in the desorption process are further controlled, the COD recovery of the agent is further improved, the recovery rate is improved, and in addition, the recovered agent is recycled, so that not only can the new agent for the flotation of a new batch of minerals be reduced, but also the flotation recovery rate or/and grade can be improved.

The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention, and various modifications and changes may be made by those skilled in the art. Any improvement or equivalent replacement directly or indirectly applied to other related technical fields within the spirit and principle of the invention and the contents of the specification and the drawings of the invention shall be included in the protection scope of the invention.

Claims

1. A selective desorption method of mineral surface agents is characterized in that a desorbent is added into ore pulp of minerals with chelating agents on the surface, the minerals and the agents are desorbed under the assistance of high-speed stirring, and then the minerals and the recovered agents are obtained through solid-liquid separation;

the medicament comprises a chelating collector;

the desorbent is acid or alkali; and the dosage of the desorbent is 30-100 g/t.

2. The method according to claim 1, wherein the chelating agent is at least one of a hydroximic acid collector, an organic phosphonic acid collector and a hydroxylamine collector.

3. The method of claim 1 wherein the chelating collector is one or more of benzohydroxamic acid, salicylhydroxamic acid, octylhydroxamic acid, styrenephosphonic acid, and ammonium N-nitrosophenylhydroxylamine.

4. The method of claim 1, wherein the mineral species comprises one or more of tungsten ore, tin ore, rare earth ore, rutile and ilmenite.

5. The method of claim 1, wherein the pulp concentration is 10-70%.

6. The method of claim 1, wherein the pulp concentration is 15-60%.

7. The method of claim 1, wherein the acid ionizes H in water⁺The substance of (1).

8. The method of claim 7, wherein the acid is at least one of hydrochloric acid and sulfuric acid.

9. The method of claim 1, wherein the base ionizes OH in water^-The substance of (1).

10. The method of claim 9, wherein the base is at least one of a hydroxide and a carbonate of an alkali metal.

11. The method of claim 1, wherein the high speed stirring speed is 2000 to 3000 r/min.

12. The method according to claim 1, wherein the temperature of the desorption process is room temperature.

13. The method according to claim 1, wherein the temperature during desorption is 5 to 40 ℃.

14. The method according to claim 1, wherein the desorption time is 10 to 30 min.

15. The method according to claim 1, wherein the mineral after the analysis and the recovered chemical are recovered by performing solid-liquid separation after the analysis.

16. The method according to claim 15, wherein the solid-liquid separation means is centrifugation.

17. The method of claim 16, wherein the rotation speed of the centrifuge is 800 to 1400 r/min.

18. A method for recycling a mineral surface agent, which is characterized in that the recovered agent is obtained by the method of any one of claims 1 to 17; and recycling the recovered chemicals to the flotation of the next batch of minerals.

19. The method of claim 18 wherein the recycled chemical is mixed with a reduced amount of new chemical for flotation of the next batch of minerals; the decrement proportion of the new medicament is 15-50%.