CN110560254B - Separation process for reducing sulfur and ash in coal - Google Patents

Separation process for reducing sulfur and ash in coal Download PDF

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Publication number
CN110560254B
CN110560254B CN201910943582.XA CN201910943582A CN110560254B CN 110560254 B CN110560254 B CN 110560254B CN 201910943582 A CN201910943582 A CN 201910943582A CN 110560254 B CN110560254 B CN 110560254B
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coal
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sulfur
fine
ball
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CN110560254A (en
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于伟
刘莉君
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Xian University of Science and Technology
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Xian University of Science and Technology
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03BSEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B7/00Combinations of wet processes or apparatus with other processes or apparatus, e.g. for dressing ores or garbage
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03BSEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B9/00General arrangement of separating plant, e.g. flow sheets
    • B03B9/005General arrangement of separating plant, e.g. flow sheets specially adapted for coal

Abstract

The invention discloses a separation process for reducing sulfur and ash in coal, which comprises the following steps: firstly, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigged clean coal; secondly, feeding the jigging cleaned coal into a crusher to be crushed to obtain a crushed product; thirdly, feeding the fine crushed product into a ball mill for ball milling to obtain a ball milled product; introducing the fine ball grinding product into an ore pulp preprocessor, adding a medicament and water, and stirring to obtain ore pulp of the fine ball grinding product; fifthly, introducing the ore pulp of the fine ball grinding product into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal; sixthly, feeding the flotation clean coal into a defoaming bucket for stirring treatment to obtain defoaming clean coal; seventhly, feeding the defoaming clean coal into a centrifugal separator for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal; eighthly, respectively dehydrating the water-containing low-ash low-sulfur clean coal and the tail coal. The invention can reduce the sulfur content and ash content in the high-sulfur coal, and has high desulfurization and deashing efficiency and simple process flow.

Description

Separation process for reducing sulfur and ash in coal
Technical Field
The invention relates to the technical field of coal desulfurization and deashing, in particular to a separation process for reducing sulfur and ash in coal.
Background
At the present stage, the most important energy resource in China is coal, and the strong energy status of the coal still cannot be changed in a long time. About 1/3 in the coal content of China is high-sulfur coal, and about 1/6 in the coal mining amount in China is high-sulfur coal at present. The sulfur content in the coal is reduced, the sulfur dioxide emission in the coal burning process can be effectively reduced, the pollution to the atmosphere is reduced, and meanwhile, the reasonable allocation of coal resources, especially the reasonable utilization of coking coal resources, is of great significance. Therefore, it is necessary to develop clean desulfurization utilization of high-sulfur coal.
The form of sulfur in most high-sulfur coal in China is mainly pyrite, only a few areas are mainly organic sulfur, and the content of sulfate sulfur in coal is very low. The organic sulfur in the coal is difficult to remove by using a physical method, and the main sulfur capable of being removed is the pyrite.
The formation process of pyrite in coal is influenced by environment and space, so that the pyrite has different forms. The aggregation morphology of pyrite in coal will be directly related to the choice of the desulfurization method of coal and the final desulfurization effect achieved.
Currently, coal desulfurization methods can be broadly classified into three major categories, i.e., physical desulfurization, chemical desulfurization, and biological (bacterial) desulfurization, according to the desulfurization principle. Because of the high cost, both chemical and biological desulfurization methods are still in the experimental and research stages, and only physical desulfurization methods are used in production practice. The physical desulfurization of coal is mainly a process of separating pyrite from coal by using the difference of physical or physicochemical properties between the pyrite in coal and the coal, such as separating pyrite from coal by using the difference of density, electrical property, magnetic property and surface property between pyrite and coal. However, although the sulfur content and ash content in the coal can be reduced by the physical separation method and the conventional flotation method, the total sulfur content of the clean coal after most of the high-sulfur coal is separated is still about 2.0%, the requirement of coking and coal blending on sulfur content is difficult to meet, and the effective utilization of the coking coal is severely restricted. For fine-grained high-sulfur coal slime, the conventional flotation has the defect of low desulfurization selectivity, the desulfurization effect in the existing production is not ideal enough, and the yield of clean coal is reduced sharply by multiple times of concentration.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a separation process for reducing sulfur and ash in coal, wherein the separation process comprises the steps of discharging a part of large gangue from the coal through jigging gravity separation, crushing and finely grinding the jigged clean coal, and then carrying out flotation and centrifugal separation and a combined separation process, so that the sulfur and ash in the high-sulfur coal are reduced, and meanwhile, the separation process has the advantages of high desulfurization and ash removal efficiency, simple process flow, easiness in operation, easiness in industrial realization and strong applicability.
In order to achieve the purpose, the invention adopts the technical scheme that: a separation process for reducing sulfur and ash in coal is characterized by comprising the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 6-0 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 70-80% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 10-20%;
the preparation method comprises the following steps of adding reagents, namely a regulator, a collector and a foaming agent in sequence when the reagents are added, wherein the regulator is used for 1-4 kg/t of fine ball mill product, the collector is used for 0.5-1.2 kg/t of fine ball mill product, and the foaming agent is used for 0.5-0.8 kg/t of fine ball mill product;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: the regulator is calcium oxide, sodium sulfide or ammonium sulfate.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: the collecting agent is kerosene or diesel oil, and the foaming agent is sec-octanol.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: the process of adding the medicament in the fourth step is as follows: and (3) after the regulator is added, stirring for 2-4 minutes, then adding the collecting agent, stirring for 2-4 minutes, and finally adding the foaming agent.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: and the rotating speed of the centrifugal separator in the step seven is 400-1000 revolutions per minute.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: and the granularity of the fine crushed product in the second step is 3 mm.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: and in the third step, the fine ball milled product with the particle size of less than 200 meshes accounts for 75% of the mass of the whole fine ball milled product.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: in the fourth step, the mass percentage concentration of the ore pulp of the fine ball grinding product is 15%.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: in the fourth step, the dosage of the regulator is 2.5kg/t of fine ball milling product, the dosage of the collector is 0.85kg/t of fine ball milling product, and the dosage of the foaming agent is 0.65kg/t of fine ball milling product.
The comprehensive utilization process for reducing the ash content of the high-sulfur coal is characterized by comprising the following steps of: the low-ash and low-sulfur clean coal refers to the low-ash and low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%.
Compared with the prior art, the invention has the following advantages:
1. the invention combines gravity separation, flotation and centrifugal separation processes to realize the removal of sulfur in coal from lump coal and fine coal slime, the elimination of sulfur in lump coal from a large part of gangue through jigging gravity separation, then the crushing and fine grinding of jigged fine coal, and the parallel combination of flotation and centrifugal separation and separation processes to reduce sulfur and ash in high-sulfur coal and realize the separation of fine coal.
2. Aiming at the importance of the influence of sulfur and ash in coal on the processing and utilizing process and the severity of environmental pollution in the combustion process and the problem of single treatment method, the invention researches a technology for removing sulfur and ash, wherein under the condition that mineral compositions in coal have different disseminated particle sizes, large impurities are removed by jigging, and fine disseminated mineral substances are subjected to a flotation and centrifugal separation process in a dissociation state to obtain a low-ash and low-sulfur refined coal product. By reducing the sulfur content and the ash content in the coal, the utilization rate of the high-sulfur coal can be improved, the environmental pollution in the processing and utilization process can be reduced, and a new utilization means can be developed according to the properties of low-ash low-sulfur coal products.
3. Coal is still an important energy source material, but the impurity content is high, and great environmental pollution is generated in the subsequent coal processing and utilizing process. In order to reduce the influence of high-ash and high-sulfur products on the subsequent treatment process, large-particle-level gangue is removed by a gravity separation method, then crushing and grinding are carried out to reduce the particle size of coal products, so that the sulfur in the coal is fully dissociated, then ash content and partial sulfur are greatly reduced by flotation, and the desulfurization effect is enhanced by a centrifugal separation mode, so that the pollution of the high-sulfur coal to the environment in the utilization process is finally reduced, fine-particle-level low-ash and low-sulfur clean coal products, high-ash products and high-sulfur products are obtained, the low-ash and low-sulfur clean coal products are processed and utilized after being dehydrated, and the pollution of impurities to the environment in the utilization process is reduced.
In conclusion, the invention takes high-sulfur coal as a research object, large-particle-level gangue is removed by a gravity separation method, the influence of high-ash high-sulfur products on the subsequent treatment process is reduced, then the crushing and grinding are carried out to reduce the particle size of the coal product, the sulfur in the coal is fully dissociated, the ash content and partial sulfur are greatly reduced by flotation, the desulfurization effect is enhanced by a centrifugal separation mode, and finally the pollution of the high-sulfur coal to the environment in the utilization process is reduced.
The invention is described in further detail below with reference to the figures and examples.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
Example 1
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 3 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 80% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 20%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 3 minutes, then adding the collecting agent, stirring for 4 minutes, and finally adding the foaming agent; the using amount of the regulator is 2kg/t of fine ball milling product, the using amount of the collector is 1kg/t of fine ball milling product, and the using amount of the foaming agent is 0.65kg/t of fine ball milling product; the modifier is calcium oxide, the collector is kerosene, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 700 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 2
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 5 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 78% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 10%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 2 minutes, then adding the collecting agent, stirring for 3 minutes, and finally adding the foaming agent; the using amount of the regulator is 2.5kg/t of fine ball milling product, the using amount of the collector is 0.5kg/t of fine ball milling product, and the using amount of the foaming agent is 0.8kg/t of fine ball milling product; the regulator is ammonium sulfate, the collector is diesel oil, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 500 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 3
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 2 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 70% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 12%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 2 minutes, then adding the collecting agent, stirring for 2 minutes, and finally adding the foaming agent; the using amount of the regulator is 2.8kg/t of fine ball milling product, the using amount of the collector is 1.1kg/t of fine ball milling product, and the using amount of the foaming agent is 0.7kg/t of fine ball milling product; the modifier is sodium sulfide, the collector is kerosene, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 800 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 4
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 6 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 75% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 18%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 4 minutes, then adding the collecting agent, stirring for 3 minutes, and finally adding the foaming agent; the using amount of the regulator is 3kg/t of fine ball milling product, the using amount of the collector is 0.6kg/t of fine ball milling product, and the using amount of the foaming agent is 0.6kg/t of fine ball milling product; the modifier is calcium oxide, the collector is kerosene, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 400 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 5
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 3 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after grading treatment is carried out on the ball-milled products, coarse ball-milled products and fine ball-milled products are obtained, the coarse ball-milled products are returned to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, and the fine ball-milled products with the particle size of less than 200 meshes account for 72% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 15%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 3 minutes, then adding the collecting agent, stirring for 2 minutes, and finally adding the foaming agent; the using amount of the regulator is 1kg/t of fine ball milling product, the using amount of the collector is 1.2kg/t of fine ball milling product, and the using amount of the foaming agent is 0.5kg/t of fine ball milling product; the modifier is sodium sulfide, the collector is diesel oil, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 900 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 6
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 4 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 80% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 14%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 2 minutes, then adding the collecting agent, stirring for 2 minutes, and finally adding the foaming agent; the using amount of the regulator is 3kg/t of fine ball milling product, the using amount of the collector is 0.8kg/t of fine ball milling product, and the using amount of the foaming agent is 0.8kg/t of fine ball milling product; the modifier is sodium sulfide, the collector is kerosene, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 600 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 7
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 0 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 76% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 20%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 3 minutes, then adding the collecting agent, stirring for 4 minutes, and finally adding the foaming agent; the using amount of the regulator is 2.2kg/t of fine ball milling product, the using amount of the collector is 0.7kg/t of fine ball milling product, and the using amount of the foaming agent is 0.6kg/t of fine ball milling product; the regulator is calcium oxide, the collector is diesel oil, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 1000 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 8
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 6 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 80% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 15%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 4 minutes, then adding the collecting agent, stirring for 2 minutes, and finally adding the foaming agent; the using amount of the regulator is 4kg/t of fine ball milling product, the using amount of the collector is 0.85kg/t of fine ball milling product, and the using amount of the foaming agent is 0.7kg/t of fine ball milling product; the regulator is ammonium sulfate, the collector is diesel oil, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 850 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Example 9
As shown in FIG. 1, the sorting process for reducing the sulfur content and the ash content in the coal in the embodiment comprises the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 1 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 75% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 10%;
wherein, the medicament is regulator, collector and foaming agent, and when adding the medicament, adds according to the order of regulator, collector and foaming agent in proper order, and is specific, and the process of adding the medicament is: after the regulator is added, stirring for 3 minutes, then adding the collecting agent, stirring for 3 minutes, and finally adding the foaming agent; the using amount of the regulator is 2.5kg/t of fine ball milling product, the using amount of the collector is 0.9kg/t of fine ball milling product, and the using amount of the foaming agent is 0.5kg/t of fine ball milling product; the modifier is calcium oxide, the collector is kerosene, and the foaming agent is sec-octanol;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator with the rotating speed of 700 revolutions per minute for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal, wherein the low-ash low-sulfur clean coal refers to the low-ash low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
Coal is still an important energy source material, but the impurity content is high, and great environmental pollution is generated in the subsequent coal processing and utilizing process. In order to reduce the influence of high-ash high-sulfur products on the subsequent treatment process, the invention applies a separation process for reducing sulfur and ash in coal, firstly jigging and separating are carried out through a jigger to discharge large pieces of gangue, then the jigged clean coal is crushed and ground to reduce the granularity of the coal products, so that the sulfur in the coal is fully dissociated, then the ash and partial sulfur are greatly reduced through flotation, then the desulfurization effect is enhanced through a centrifugal separation mode, finally the pollution of the high-sulfur coal to the environment in the utilization process is reduced, fine-particle low-ash low-sulfur clean coal products, high-ash products and high-sulfur products are obtained, the low-ash low-sulfur clean coal products are processed and utilized after being dehydrated, and the pollution of impurities to the environment in the utilization process is reduced.
The separation process for reducing the sulfur content and the ash content in the coal provided by the above embodiments 1 to 9 combines the gravity separation, the flotation and the centrifugal separation processes, has high desulfurization and deashing rates, can improve the desulfurization rate of the high-sulfur coal with uneven granularity distribution or fine particle distribution to 80 to 90 percent, has simple process flow, is easy to operate, is easy to realize industrially, and has strong applicability.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims (6)

1. A separation process for reducing sulfur and ash in coal is characterized by comprising the following steps:
step one, feeding high-sulfur coal into a jigger for jigging and sorting to obtain jigging clean coal and jigging tail coal;
step two, feeding the jigging cleaned coal obtained in the step one into a crusher for crushing to obtain a crushed product; after grading treatment is carried out on the crushed product, a coarse crushed product and a fine crushed product are obtained, the coarse crushed product is returned to the crusher to be crushed again until the coarse crushed product is crushed into the fine crushed product, and the granularity of the fine crushed product is 6-0 mm;
step three, feeding the fine crushed product obtained in the step two into a ball mill for ball milling to obtain a ball milled product; after the ball-milled products are subjected to grading treatment, obtaining coarse ball-milled products and fine ball-milled products, returning the coarse ball-milled products to the ball mill for ball milling again until the coarse ball-milled products are ball-milled into the fine ball-milled products, wherein the fine ball-milled products with the particle size of less than 200 meshes account for 70-80% of the mass of the whole fine ball-milled products;
step four, introducing the fine ball grinding product obtained in the step three into an ore pulp preprocessor, then adding a medicament into the ore pulp preprocessor and fully mixing the medicament with the fine ball grinding product to obtain ore pulp of the fine ball grinding product, wherein the mass percentage concentration of the ore pulp of the fine ball grinding product is 10-20%;
the preparation method comprises the following steps of adding reagents, namely a regulator, a collector and a foaming agent in sequence when the reagents are added, wherein the regulator is used for 1-4 kg/t of fine ball mill product, the collector is used for 0.5-1.2 kg/t of fine ball mill product, and the foaming agent is used for 0.5-0.8 kg/t of fine ball mill product;
the modifier is calcium oxide, sodium sulfide or ammonium sulfate, the collector is kerosene or diesel oil, and the foaming agent is sec-octanol;
the process of adding the medicament in the fourth step is as follows: after adding the regulator, stirring for 2-4 minutes, then adding the collecting agent, stirring for 2-4 minutes, and finally adding the foaming agent;
step five, introducing the fine ball grinding product ore pulp obtained in the step four into a flotation machine for flotation to obtain flotation clean coal and flotation tail coal;
step six, feeding the flotation clean coal obtained in the step five into a defoaming bucket for defoaming treatment to obtain defoaming clean coal;
step seven, feeding the defoaming clean coal obtained in the step six into a centrifugal separator for centrifugal separation to obtain water-containing low-ash low-sulfur clean coal and centrifugal tail coal; the rotating speed of the centrifugal separator is 400-1000 rpm;
step eight, dehydrating the water-containing low-ash low-sulfur clean coal obtained in the step seven to obtain a product, namely the low-ash low-sulfur clean coal; and dehydrating the flotation tailings obtained in the fifth step and the centrifugal tailings obtained in the seventh step to obtain high-sulfur tailings.
2. The separation process for reducing the sulfur content and the ash content in the coal according to claim 1, wherein the separation process comprises the following steps: and the granularity of the fine crushed product in the second step is 3 mm.
3. The separation process for reducing the sulfur content and the ash content in the coal according to claim 1, wherein the separation process comprises the following steps: and in the third step, the fine ball milled product with the particle size of less than 200 meshes accounts for 75% of the mass of the whole fine ball milled product.
4. The separation process for reducing the sulfur content and the ash content in the coal according to claim 1, wherein the separation process comprises the following steps: in the fourth step, the mass percentage concentration of the ore pulp of the fine ball grinding product is 15%.
5. The separation process for reducing the sulfur content and the ash content in the coal according to claim 1, wherein the separation process comprises the following steps: in the fourth step, the dosage of the regulator is 2.5kg/t of fine ball milling product, the dosage of the collector is 0.85kg/t of fine ball milling product, and the dosage of the foaming agent is 0.65kg/t of fine ball milling product.
6. The separation process for reducing the sulfur content and the ash content in the coal according to claim 1, wherein the separation process comprises the following steps: the low-ash and low-sulfur clean coal refers to the low-ash and low-sulfur clean coal with the ash content of less than 10% and the sulfur content of less than 2%.
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