CN113560045A

CN113560045A - Method for enhancing flotation selectivity of coal slime

Info

Publication number: CN113560045A
Application number: CN202110698544.XA
Authority: CN
Inventors: 李宏亮; 徐雯楠; 孙玉金; 潘昱蒿
Original assignee: Taiyuan University of Technology
Current assignee: Taiyuan University of Technology
Priority date: 2021-06-23
Filing date: 2021-06-23
Publication date: 2021-10-29

Abstract

The invention discloses a method for strengthening flotation selectivity of coal slime, belongs to the technical field of mineral processing, and aims to simultaneously strengthen the flotation effect of coarse grains and fine grains of the coal slime. The agent can be adsorbed on the surfaces of coal particles and mineral particles to promote coal flotation and inhibit gangue, and the flotation effects of aviation kerosene and emulsified aviation kerosene can be improved, so that the yield of flotation clean coal is greatly improved, the ash content is greatly reduced, and the agent consumption is reduced.

Description

Method for enhancing flotation selectivity of coal slime

Technical Field

The invention belongs to the technical field of mineral processing, and particularly relates to a method for enhancing flotation selectivity of coal slime.

Background

Coal is the main energy of China, and accounts for 62% of the total energy consumption in the energy structure of China. With the adoption of mechanized coal mining means and the increase of the content of gangue in raw coal, the content of fine particles in a separation medium is increased more and more. As an effective means for fine particle separation, coal slime flotation is increasingly important in coal dressing. Under the condition of serious slime argillization, the content of fine mud in the flotation suspension is high, and the fine mud covers coal particle phases, so that the poor flotation effect is easily caused.

In the aspect of medicament, in order to improve the coal slime flotation effect and save the consumption of flotation medicament, experts and scholars at home and abroad carry out a great deal of related work, and mainly carry out a great deal of research and exploration on the aspects of the optimization and the reinforced emulsification process of the emulsifier. In the optimization aspect of the emulsifier, a single surfactant is selected as the emulsifier, and the emulsifier is preferably compounded by two or more surfactants; in the emulsification process, the medicament tends to be stirred in turn in a comprehensive manner in recent years, such as high-pressure jet cutting, ultrasonic crushing and homogenizing, strong magnetization and the like. The dispersed phase particles of the emulsion prepared by the method are smaller, and the stability is also improved.

However, the flotation effect can be remarkably improved after the collector is not emulsified. For coarse flotation, the flotation agent with larger liquid drops can effectively collide with target minerals for collection. For fine-grained flotation, the flotation agent with small liquid drops not only collects fine-grained coal, but also forms a large entrainment effect, and the yield of clean coal cannot be obviously improved. The coal slurry flotation is a wide-size flotation, and in order to strengthen the coal slurry flotation, the effect of collecting coarse particles and fine particles must be strengthened at the same time.

Disclosure of Invention

The invention aims to provide a method for strengthening the flotation selectivity of coal slime, and the method breaks through the flotation effect of simultaneously strengthening coarse grains and fine grains of the coal slime. And the consumption of the flotation reagent can be greatly reduced.

The invention adopts the following technical scheme:

a method for enhancing the flotation selectivity of coal slime comprises the following steps:

adding a reagent into the flotation coal slurry, stirring to enable the reagent to be adsorbed to the surfaces of coal slurry particles, and performing flotation;

the agent comprises methylene blue;

the collecting agent in the flotation coal slurry comprises aviation kerosene or emulsified aviation kerosene.

Furthermore, the addition amount of the aviation kerosene is 2340g added in each ton of coal slime, and the addition amount of the chemical agent is 400g added in each ton of coal slime.

Furthermore, the addition amount of the emulsified aviation kerosene is 333.33g added in each ton of coal slime, and the addition amount of the medicament is 666.66g or 1333.33g added in each ton of coal slime.

The agent provided by the invention can greatly enhance the flotation effect, and can be independently used as a collecting agent for certain coal types.

Coal is an organic matter, so the invention can also be used as an enhancement aid for organic/inorganic substance separation or directly used as a collector for organic/inorganic substance separation.

The invention has the following beneficial effects:

according to the invention, based on the properties of the coal surface and the properties and characteristics of the gangue surface, the methylene blue medicament is adsorbed to the surfaces of coal and gangue in the aqueous solution, and under the combined action of the flotation medicament, the coal collecting effect and the gangue inhibiting effect are strengthened, and the coal slime flotation is strengthened. The consumption of a flotation reagent can be greatly reduced, the flotation cost is saved, and the yield of clean coal can be greatly improved, so that the efficiency of the flotation reagent is greatly improved, the ash content of the flotation clean coal is greatly reduced, and the selectivity of coal slime flotation is improved.

Drawings

Figure 1 shows the flotation yield of aviation kerosene alone added in example 1 of the present invention.

FIG. 2 shows the amount of ash of aviation kerosene added alone in example 1 of the present invention.

Figure 3 shows the flotation recovery with the addition of the agent alone according to example 1 of the present invention.

FIG. 4 shows the ash of example 1 of the present invention with a separate chemical added.

Figure 5 is the agent + aviation kerosene flotation recovery of example 1 of the present invention.

Figure 6 is the inventive example 1 agent + aviation kerosene flotation ash.

Figure 7 shows the flotation recovery of emulsified aviation kerosene alone in example 2 of the present invention.

FIG. 8 is ash content with the addition of emulsified jet fuel alone in accordance with example 2 of the present invention.

Figure 9 shows the flotation recovery of agent + emulsified aviation kerosene in example 2 of the present invention.

Figure 10 is the example 2 agent + emulsified aviation kerosene flotation ash of the present invention.

Detailed Description

Example 1

The coal used in the embodiment is coal for coking of coal bed No. 2 of West mountain of Shanxi province. The method is used for strengthening the coal slime flotation by using the conventional aviation kerosene as a collecting agent.

According to the flotation method, 2340g/t aviation kerosene is used as a collector for flotation, the foaming amount is 6 times that of the collector, the reagent is added on the basis of the reagent, the flotation effect of the reagent is compared with that of the reagent which is not added, and under the condition that 400g/t of the reagent is added, the yield of clean coal is improved to 41.49% from 13.25%, the ash content of the clean coal is reduced to 10.47% from 28.63%, and the ash content of tail coal is improved to 62.13% from 42.67%. The flotation effect of the aviation kerosene is enhanced, the yield of flotation clean coal is greatly improved, and the ash content is greatly reduced. The flotation effect of only adding the medicament is found to be poorer than that of kerosene plus medicament by only adding the medicament for flotation, so that the effect of adding the medicament A is the strengthening of the conventional collecting.

As shown in fig. 1 and fig. 2, after aviation kerosene is added alone, clean coal and tail coal yield and ash content of coal slime flotation are obtained. The yield of clean coal is increased, the yield of tail coal is reduced, the ash content of clean coal is reduced, and the ash content of tail coal is increased with the increase of the addition amount of aviation kerosene, but the amplitudes are all insignificant, when the aviation kerosene is increased from 1100g/t to 10400g/t, the yield of clean coal is increased from 11% to 24.19%, and the yield of tail coal is decreased from 89% to 76.80%. Clean coal ash decreased from 31% to 14%, and tail coal ash increased from 41% to 49%.

As shown in fig. 3 and 4, the agent is added separately, so that the yield of clean coal and tail coal and ash content of coal slime flotation are improved. With the increase of the addition amount of the chemical agent, the yield of clean coal is reduced after being increased, the yield of tail coal is increased after being reduced, the ash content of clean coal is increased after being reduced, the ash content of tail coal is reduced after being increased, but the range is larger, and reaches an extreme value when the chemical agent amount is 400 g/t. When the agent is increased from 66.67g/t to 400g/t, the yield of clean coal is increased from 4 percent to 27.58 percent, and the yield of tail coal is reduced from 96 percent to 72 percent. Clean coal ash content decreased from 26% to 12.87%, and tail coal ash content increased from 37% to 48.52%.

As shown in the figure 5 and the figure 6, after the chemicals and the aviation kerosene are added, the yield of clean coal and tail coal of the coal slime flotation and the ash content are achieved, wherein the amount of the aviation kerosene is 2340 g/t. Along with the increase of the addition amount of the chemical agent, the yield of clean coal is increased to a certain extent, the chemical agent tends to be gentle when reaching 400g/t, the yield of tail coal is reduced to a certain extent, the chemical agent tends to be gentle when reaching 400g/t, the ash content of clean coal is reduced to a certain extent, the chemical agent tends to be gentle when reaching 400g/t, the ash content of tail coal is increased to a certain extent, and the chemical agent tends to be gentle when reaching 400 g/t. When the agent is increased from 0g/t to 400g/t, the yield of clean coal is increased from 13.25 percent to 41.49 percent, and the yield of tail coal is reduced from 86.75 percent to 59.10 percent. Clean coal ash decreased from 28.63% to 10.47%, and tail coal ash increased from 42.67% to 62.13%.

Example 2

The coal slurry flotation is carried out by adopting 333.33g/t emulsified aviation kerosene, after 666.66g/t and 1333.33g/t of chemicals are respectively added, the yield of clean coal is respectively improved to 48.06 percent and 56.71 percent from 12.32 percent, the ash content of the clean coal is respectively reduced to 10.58 percent and 11.64 percent from 12.10 percent, and the ash content of tail coal is respectively improved to 64.31 percent and 74.56 percent from 44.09 percent. The flotation effect of the emulsified aviation kerosene is enhanced, and the yield of the emulsified aviation kerosene flotation clean coal is greatly improved. Compared with common aviation kerosene flotation, the emulsification and reagent flotation effect reduces the consumption of the collector reagent from 2340g/t to 333.33 g/t.

As shown in fig. 7 and 8, the yield of clean coal and tail coal and ash content of coal slurry flotation are obtained after emulsified aviation kerosene is added separately. The yield of clean coal is increased with the increase of the addition amount of the emulsified aviation kerosene, the yield of tail coal is reduced, the ash content of clean coal is reduced, the ash content of tail coal is increased, when the emulsified aviation kerosene is increased from 100g/t to 466.67g/t, the yield of clean coal is increased from 7 percent to 28.77 percent, and the yield of tail coal is decreased from 93 percent to 71.23 percent. Clean coal ash content decreased from 27% to 13.31%, and tail coal ash content increased from 38% to 50.31%. The addition amount of emulsified kerosene is greatly reduced compared with that of non-emulsified kerosene.

As shown in figure 10 of figure 9, the agent and the emulsified aviation kerosene are added, the yield of clean coal and tail coal of the coal slime flotation and the ash content are respectively, and the amount of the emulsified kerosene is 333.33 g/t. Along with the increase of the addition amount of the chemical agent, the yield of clean coal is increased, the yield of tail coal is reduced, the ash content of the clean coal is reduced, the ash content of the tail coal is increased, and the range is obvious. When the agent is increased from 0g/t to 333.33g/t, the yield of clean coal is increased from 12% to 38.16%, and the yield of tail coal is reduced from 87.68% to 61.84%. Clean coal ash content decreased from 27% to 9.06%, and tail coal ash content increased from 44.10% to 57.09%. The agent further improves the yield of clean coal and further reduces the ash content of the clean coal. When the addition amounts of the chemicals reach 666.66g/t and 1333.33g/t respectively, the yields of clean coal are respectively improved from 12.32% to 48.06% and 56.71%, the ash content of the clean coal is respectively reduced from 12.10% to 10.58% and 11.64%, and the ash content of the tail coal is respectively improved from 44.09% to 64.31% and 74.56%. Compared with common aviation kerosene flotation, the emulsification and medicament flotation effects reduce the medicament consumption of the aviation kerosene from 10400g/t to 333.33g/t, the medicament consumption is 666.66g/t and 1333.33g/t, the yield of clean coal is improved from 27.58% to 48.06% and 56.71%, the ash content of the clean coal is reduced from 14% to 10.58% and 11.64%, the collecting effect and selectivity are greatly enhanced, the cost reduction and the benefit increase can be expected to be brought to industrial production.

Claims

1. A method for enhancing the flotation selectivity of coal slime is characterized by comprising the following steps: the method comprises the following steps:

the agent comprises methylene blue;

2. The method for enhancing the flotation selectivity of the coal slime according to claim 1, characterized by comprising the following steps of: the addition amount of the aviation kerosene is 2340g added in each ton of coal slime, and the addition amount of the medicament is 400g added in each ton of coal slime.

3. The method for enhancing the flotation selectivity of the coal slime according to claim 1, characterized by comprising the following steps of: the addition amount of the emulsified aviation kerosene is 333.33g added in each ton of coal slime, and the addition amount of the medicament is 666.66g or 1333.33g added in each ton of coal slime.