CN113122708A - Raw material pretreatment method and raw material pretreatment device for smelting reduction iron making - Google Patents
Raw material pretreatment method and raw material pretreatment device for smelting reduction iron making Download PDFInfo
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 200
- 230000009467 reduction Effects 0.000 title claims abstract description 123
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 100
- 238000003723 Smelting Methods 0.000 title claims abstract description 98
- 239000002994 raw material Substances 0.000 title claims abstract description 85
- 238000002203 pretreatment Methods 0.000 title claims abstract description 15
- 238000006722 reduction reaction Methods 0.000 claims abstract description 143
- 239000000463 material Substances 0.000 claims abstract description 99
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 73
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 73
- 239000003245 coal Substances 0.000 claims abstract description 64
- 238000000034 method Methods 0.000 claims abstract description 62
- 239000000843 powder Substances 0.000 claims abstract description 52
- 230000004907 flux Effects 0.000 claims abstract description 43
- 238000001035 drying Methods 0.000 claims abstract description 35
- 238000002156 mixing Methods 0.000 claims abstract description 26
- 239000008187 granular material Substances 0.000 claims abstract description 6
- 239000002893 slag Substances 0.000 claims description 17
- 239000002245 particle Substances 0.000 claims description 12
- 235000012054 meals Nutrition 0.000 claims description 9
- 229920006395 saturated elastomer Polymers 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 8
- 239000003034 coal gas Substances 0.000 claims description 7
- 238000005507 spraying Methods 0.000 claims description 7
- 239000000428 dust Substances 0.000 claims description 6
- 239000000446 fuel Substances 0.000 claims description 6
- 235000019738 Limestone Nutrition 0.000 claims description 5
- 239000010459 dolomite Substances 0.000 claims description 5
- 229910000514 dolomite Inorganic materials 0.000 claims description 5
- 239000006028 limestone Substances 0.000 claims description 5
- 229910000831 Steel Inorganic materials 0.000 claims description 4
- 230000035484 reaction time Effects 0.000 claims description 4
- 239000010959 steel Substances 0.000 claims description 4
- 238000000746 purification Methods 0.000 claims description 3
- 239000000779 smoke Substances 0.000 claims description 3
- 238000005469 granulation Methods 0.000 claims description 2
- 238000009856 non-ferrous metallurgy Methods 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims 1
- 230000003179 granulation Effects 0.000 claims 1
- 239000010802 sludge Substances 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 43
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 238000005272 metallurgy Methods 0.000 abstract description 2
- 230000007547 defect Effects 0.000 description 8
- 239000007789 gas Substances 0.000 description 8
- 238000012986 modification Methods 0.000 description 5
- 230000004048 modification Effects 0.000 description 5
- 238000004939 coking Methods 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 4
- 230000014759 maintenance of location Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 239000003638 chemical reducing agent Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 239000008188 pellet Substances 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- HGUFODBRKLSHSI-UHFFFAOYSA-N 2,3,7,8-tetrachloro-dibenzo-p-dioxin Chemical compound O1C2=CC(Cl)=C(Cl)C=C2OC2=C1C=C(Cl)C(Cl)=C2 HGUFODBRKLSHSI-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000005453 pelletization Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000007363 ring formation reaction Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000003911 water pollution Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/14—Agglomerating; Briquetting; Binding; Granulating
- C22B1/24—Binding; Briquetting ; Granulating
- C22B1/2406—Binding; Briquetting ; Granulating pelletizing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/0066—Preliminary conditioning of the solid carbonaceous reductant
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/0086—Conditioning, transformation of reduced iron ores
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- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Mechanical Engineering (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention provides a raw material pretreatment method for smelting reduction ironmaking, belonging to the technical field of metallurgy, and the method comprises the following steps: mixing the iron-containing material, the coal powder and the flux according to the mass ratio of 100: 15-30: 5-8 to obtain a mixed material; granulating the mixed material to obtain a carbon-containing prefabricated granule raw material; and drying the carbon-containing prefabricated grain raw material, and then carrying out pre-reduction reaction to obtain the carbon-containing prefabricated grain clinker. The method can improve the reduction degree of iron-containing materials in the raw materials and reduce the smelting load of the smelting reduction furnace on the basis of realizing preheating of the smelting reduction iron-making raw materials, and is beneficial to improving the yield of the smelting reduction iron-making process. The invention also provides a raw material pretreatment device for smelting reduction ironmaking.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to a raw material pretreatment method and a raw material pretreatment device for smelting reduction ironmaking.
Background
The steel industry is a national prop industry and is also a large energy consumer. At present, the mainstream blast furnace ironmaking process must be subjected to raw fuel pretreatment processes such as coking, sintering, pelletizing and the like, so that serious atmospheric and water pollution is caused. With the continuous decrease of coking coal resources, the development of non-blast furnace iron-making production process directly using non-coking coal and iron ore powder is urgent.
The smelting reduction iron-smelting process directly uses raw fuels such as non-coking coal, iron ore powder and the like, the ore powder with the granularity of less than 6mm is preheated and pre-reduced by a preheater and then is sprayed into a smelting reduction furnace by a spray gun, and iron oxide is reduced into molten iron by carbon in a high-temperature smelting state. The method does not use coke, sinter and pellet, and greatly reduces CO2、NOxAnd the emission of dioxin, has the advantages of simple process, high utilization efficiency of resources and energy, small environmental pollution and the like, has very bright prospect for smelting reduction, and is a hot spot for the research of the iron-making industry all the time.
In the smelting reduction iron-making process, the pre-reduction degree of iron ore powder is lower, usually 10-12% or even lower, by the existing pretreatment process, namely the preheating pre-reduction process, so that the smelting load of a smelting reduction furnace is greatly increased, and the yield of the smelting reduction iron-making process is reduced. Because the raw material pretreatment process is a restrictive link of the development of the smelting reduction iron-making process, the development of a raw material pretreatment technology with simple process and high reduction efficiency is urgently needed.
Disclosure of Invention
In order to solve the technical problem of low reduction degree of iron ore powder in a raw material pretreatment process in a smelting reduction iron-making process, the invention provides a raw material pretreatment method for smelting reduction iron-making.
The invention also provides a raw material pretreatment device for smelting reduction ironmaking.
The invention is realized by the following technical scheme:
the embodiment of the invention provides a raw material pretreatment method for smelting reduction ironmaking, which comprises the following steps:
mixing the iron-containing material, the coal powder and the flux according to the mass ratio of 100: 15-30: 5-8 to obtain a mixed material;
granulating the mixed material to obtain a carbon-containing prefabricated granule raw material;
and drying the carbon-containing prefabricated grain raw material, and then carrying out pre-reduction reaction to obtain the carbon-containing prefabricated grain clinker.
Optionally, the iron-containing material comprises at least one of iron ore powder, iron-containing dust mud of iron and steel plants and iron-containing nonferrous metal metallurgical slag, the content of TFe in the iron-containing material is not less than 45%, and the particle size of the iron-containing material is 0-2 mm.
Optionally, the fixed carbon content in the pulverized coal is more than or equal to 70%, and the particle size of the pulverized coal is 0-2 mm.
Optionally, the flux comprises dolomite and/or limestone, and the granularity of the flux is 0-1 mm.
Optionally, the granulating the mixed material to obtain a carbon-containing pre-granulated raw material specifically includes:
granulating the mixture, wherein atomized saturated Ca (OH) is sprayed in the granulating process2Solution of said saturated Ca (OH)2And spraying the solution into the mixture, wherein the mass of the solution is 3-8% of that of the mixed material, and thus obtaining the carbon-containing prefabricated granular raw material with the granularity of 2-6 mm.
Optionally, the step of drying the carbon-containing prefabricated grain raw material, and then performing a pre-reduction reaction to obtain the carbon-containing prefabricated grain clinker specifically includes:
and drying the carbon-containing prefabricated granular raw materials, introducing the coal gas generated by the smelting reduction iron-making reaction and subjected to dust removal and purification to perform a pre-reduction reaction, wherein the air-fuel ratio is 0.8-1.0, the reaction temperature is 800-1100 ℃, and the reaction time is 10-30 min, so as to obtain the carbon-containing prefabricated granular clinker.
Optionally, the drying of the carbon-containing pre-granulated raw material specifically includes:
and (3) distributing the carbon-containing prefabricated granular raw material, wherein the thickness of a material layer is 200-600 mm, drying at 150-300 ℃ for 5-15 min, and taking a drying heat source as smoke generated by the pre-reduction reaction.
Based on the same conception, the embodiment of the invention also provides a raw material pretreatment device for smelting reduction iron making, the raw material pretreatment device comprises an iron-containing material bin, a pulverized coal bin, a flux bin, a mixing device, a granulating device, a distributing machine and a roasting device, discharge ports of the iron-containing material bin, the pulverized coal bin and the flux bin are all connected with a feed port of the mixing device, a discharge port of the mixing device is connected with a feed port of the granulating device, a discharge port of the granulating device is connected with a feed port of the roasting device through the distributing machine, one side of the roasting device close to the feed port is a drying area, the other side of the roasting device is a pre-reduction area, and a discharge port of the roasting device is used for being connected with a feed system of a smelting reduction furnace.
Optionally, the granulating device comprises any one of a disk pelletizer, a cylinder pelletizer and an intensive mixer, and the roasting device comprises a belt roasting machine or a grate.
Optionally, the iron-containing material bin, the pulverized coal bin and the flux bin are respectively used for storing iron-containing materials, pulverized coal and flux.
One or more technical schemes in the invention at least have the following technical effects or advantages:
1. the invention relates to a raw material pretreatment method for smelting reduction ironmaking, which is characterized in that coal powder is added into raw materials of a smelting reduction ironmaking process, the coal powder is used as a reducing substance, the defect of low content of reducing gas in smelting reduction furnace gas can be effectively overcome, so that the reduction degree of an iron-containing material is improved in a pre-reduction reaction, the reduction rate of the iron-containing material in the obtained carbon-containing prefabricated granular clinker can reach 30-60 percent, the iron-containing material is used as a raw material for smelting reduction ironmaking, the smelting load of a smelting reduction furnace can be greatly reduced, the yield of the smelting reduction furnace is improved, wherein the mass ratio of the iron-containing material, the coal powder and a flux is controlled to be 100: 15-30: 5-8, the reduction degree of the iron-containing material is favorably and fully improved, the incomplete combustion of the coal powder in the reduction and smelting processes can be increased due to the excessive mass ratio of the coal powder, the reduction rate is low, on the other hand, insufficient heat supply of a smelting reduction furnace and insufficient carburization of molten iron can be caused, the smelting efficiency and the quality of the molten iron are reduced, the flux is added for controlling the binary alkalinity of slag in the smelting reduction furnace to be 1.1-1.4, and the alkalinity of the slag is increased and the amount of the slag is increased due to overhigh flux; too low results in an increase in the melting point of the slag system, both of which result in an increase in coal consumption.
2. The invention relates to a raw material pretreatment device for smelting reduction ironmaking, wherein an iron-containing material bin, a coal powder bin and a flux bin are respectively used for storing iron-containing materials, coal powder and flux, the iron-containing materials, the coal powder and the flux enter a mixing device to be mixed uniformly to obtain a mixed material, the mixed material enters a granulating device to be granulated to obtain carbon-containing prefabricated grain raw meal, the carbon-containing prefabricated grain raw meal is uniformly distributed to a drying zone of a roasting device through a distributing machine to be dried and then enters a pre-reduction zone of the roasting device to be pre-reduced, and the obtained carbon-containing prefabricated grain clinker is used as a raw material for smelting reduction reaction. And the roasting device replaces the traditional circulating fluidized bed or a two-stage rotary kiln, thereby overcoming the defects of poor process stability, complex process and incapability of treating powder ore below 1mm in the existing smelting reduction iron-making process pretreatment device.
The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.
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 are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
FIG. 1 is a process flow diagram of a feedstock pretreatment process of the present invention;
FIG. 2 is a schematic view of the structure of the raw material pretreatment apparatus of the present invention.
In the figure: 1-iron-containing material bin, 2-pulverized coal bin, 3-flux bin, 4-mixing device, 5-granulating device, 6-distributing machine, 7-roasting device, 71-drying zone and 72-prereduction zone.
Detailed Description
The present invention will be described in detail below with reference to specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly apparent therefrom. It will be understood by those skilled in the art that these specific embodiments and examples are for the purpose of illustrating the invention and are not to be construed as limiting the invention.
Throughout this specification, unless specifically stated otherwise,
the terms used herein are to be understood as meaning as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.
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.
It should be further noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.
In order to solve the technical problems, the embodiment of the invention provides the following general ideas:
for the problem of low reduction degree of iron ore powder in the pretreatment of raw materials of a smelting reduction iron-making process, the inventor finds that the existing ore powder preheater of the smelting reduction iron-making process is usually a circulating fluidized bed, the heat source is coal gas of a smelting reduction furnace, and due to the characteristic of high secondary combustion rate of the smelting reduction iron-making process, the coal gas temperature of the smelting reduction furnace is high but the content of reducing gas is low, so that the reduction degree of the pretreated ore powder is only 10-12%, namely only preheating is performed, but pre-reduction is not performed, the smelting load of the smelting reduction furnace is greatly increased, and in addition, the fluidized bed has the problems of bonding loss, poor stability. The secondary rotary kiln preheating technology adopted in China for treating the iron ore powder simplifies the process flow and reduces the cost, but the problem of pre-reduction of the iron ore powder is still not solved, the pre-reduction degree of the preheated iron ore powder is only about 5 percent, meanwhile, the rotary kiln technology cannot treat the powder ore below 1mm due to the problem of easy ring formation at high temperature, the ore return quantity is ultrahigh when the particle size of the iron ore powder is fine, the applicability of the process to raw materials is limited, and the method is an uneconomical treatment mode.
According to an exemplary embodiment of the present invention, there is provided a raw material pretreatment method for smelting reduction iron making, as shown in fig. 1, the method including:
s1, mixing the iron-containing material, the coal powder and the flux according to the mass ratio of 100 to (15-30) to (5-8) to obtain a mixed material.
In the invention, the coal powder is added into the raw materials of the smelting reduction iron-making process, the coal powder is used as a reducing substance, the defect of low content of reducing gas in the smelting reduction furnace gas can be effectively compensated, so that the reduction degree of the iron-containing material is improved in the pre-reduction reaction, the reduction rate of the iron-containing material in the obtained carbon-containing prefabricated granulated clinker can reach 30-60%, the coal powder is used as the raw materials of the smelting reduction iron-making, the smelting load of a smelting reduction furnace can be greatly reduced, and the yield of the smelting reduction furnace is improved, wherein the mass ratio of the iron-containing material, the coal powder and a flux is controlled at 100: 15-30: 5-8, the reduction degree of the iron-containing material is favorably and fully improved, the incomplete combustion of the coal powder in the reduction and smelting processes is increased due to the overhigh mass ratio of the coal powder, the reduction rate is low, on the other hand, insufficient heat supply of a smelting reduction furnace and insufficient carburization of molten iron can be caused, the smelting efficiency and the quality of the molten iron are reduced, the flux is added for controlling the binary alkalinity of the slag of the smelting reduction furnace to be 1.1-1.4, and the alkalinity of the slag is increased and the amount of the slag is increased due to overhigh flux; too low results in an increase in the melting point of the slag system, both of which result in an increase in coal consumption.
As an optional embodiment, the iron-containing material comprises at least one of iron ore powder, iron-containing dust and mud of iron and steel plants and iron-containing nonferrous metallurgy slag, the TFe content of the iron-containing material is greater than or equal to 45%, and the particle size of the iron-containing material is 0-2 mm.
In the embodiment of the invention, the TFe content in the iron-containing material is more than or equal to 45 percent, and the lower the iron content is, the poorer the smelting economy is; the particle size of the iron-containing material is 0-2 mm, so that the material can be ensured to have better balling and reduction kinetic conditions, and the material is overlarge in particle size, poor in balling property and difficult to reduce.
As an optional implementation mode, the fixed carbon content in the pulverized coal is more than or equal to 70%, and the particle size of the pulverized coal is 0-2 mm.
In the embodiment of the invention, the content of fixed carbon in the coal powder is more than or equal to 70 percent, the higher the content of the fixed carbon is, the higher the content of the effective components is, the less the impurities and harmful elements are brought in, the energy consumption for smelting can be reduced, and the product quality can be improved; the granularity of the pulverized coal is 0-2 mm, so that the pulverized coal can be ensured to have better balling and reactivity, and the granularity is too large, the balling is poor and the reactivity is poor.
As an alternative embodiment, the flux comprises dolomite and/or limestone, the flux having a particle size of 0 to 1 mm.
S2, granulating the mixed material to obtain the carbon-containing prefabricated granular raw material.
As an optional embodiment, the granulating the mixed material to obtain the carbon-containing pre-granulated raw material specifically comprises:
granulating the mixture, wherein atomized saturated Ca (OH) is sprayed in the granulating process2Solution of said saturated Ca (OH)2And spraying the solution into the mixture, wherein the mass of the solution is 3-8% of that of the mixed material, and thus obtaining the carbon-containing prefabricated granular raw material with the granularity of 2-6 mm.
In the examples of the invention, atomized Ca (OH) is sprayed in during the granulation2The solution acts as a pellet binder.
And S3, drying the carbon-containing prefabricated grain raw material, and then carrying out pre-reduction reaction to obtain the carbon-containing prefabricated grain clinker.
As an alternative embodiment, the step of drying the carbon-containing prefabricated granular raw material and then performing a pre-reduction reaction to obtain the carbon-containing prefabricated granular clinker specifically comprises:
and drying the carbon-containing prefabricated granular raw materials, introducing the coal gas generated by the smelting reduction iron-making reaction and subjected to dust removal and purification to perform a pre-reduction reaction, wherein the air-fuel ratio is 0.8-1.0, the reaction temperature is 800-1100 ℃, and the reaction time is 10-30 min, so as to obtain the carbon-containing prefabricated granular clinker.
In the embodiment of the invention, the pre-reduction reaction takes clean coal gas generated by smelting reduction iron-making reaction as a heat source, the air-fuel ratio is 0.8-1.0, the reaction temperature is controlled at 800-1100 ℃, the reaction time is controlled at 10-30 min, materials with over-high temperature are easy to melt and agglomerate, the temperature is too low, and the reduction rate of the materials is low.
As an alternative embodiment, the drying the carbon-containing pre-granulated raw meal specifically includes:
and (3) distributing the carbon-containing prefabricated granular raw material, wherein the thickness of a material layer is 200-600 mm, drying at 150-300 ℃ for 5-15 min, and taking a drying heat source as smoke generated by the pre-reduction reaction.
In the embodiment of the invention, the thickness of the material layer is 200-600 mm, if the material layer is too thick, the material layer is difficult to dry completely, and if the material layer is too thin, the production rate is low; drying for 5-15 min at 150-300 ℃, which is beneficial to controlling the moisture content of the carbon-containing prefabricated grain clinker below 3%, and realizing the reutilization of the flue gas generated by the pre-reduction reaction as a drying heat source.
According to another typical embodiment of the invention, a raw material pretreatment device for smelting reduction iron making is provided, the raw material pretreatment device comprises an iron-containing material bin, a pulverized coal bin, a flux bin, a mixing device, a granulating device, a distributing machine and a roasting device, discharge ports of the iron-containing material bin, the pulverized coal bin and the flux bin are all connected with a feed port of the mixing device, a discharge port of the mixing device is connected with a feed port of the granulating device, a discharge port of the granulating device is connected with a feed port of the roasting device through the distributing machine, one side of the roasting device close to the feed port is a drying area, the other side of the roasting device is a pre-reduction area, and a discharge port of the roasting device is used for being connected with a feeding system of a smelting reduction furnace.
In the invention, an iron-containing material bin, a coal powder bin and a flux bin are respectively used for storing iron-containing materials, coal powder and a flux, the iron-containing materials, the coal powder and the flux enter a mixing device to be mixed uniformly to obtain a mixed material, the mixed material enters a granulating device to be granulated to obtain carbon-containing prefabricated grain raw meal, the carbon-containing prefabricated grain raw meal is uniformly distributed to a drying zone of a roasting device through a distributing machine to be dried and then enters a pre-reduction zone of the roasting device to be pre-reduced, and the obtained carbon-containing prefabricated grain clinker is used as a raw material of a smelting reduction reaction. The defects that the existing pretreatment device and process of the smelting reduction iron-making process are poor in stability, complex in process and incapable of treating ore fines with the particle size of less than 1mm are overcome.
As an alternative embodiment, the granulating device comprises any one of a disk pelletizer, a drum pelletizer and an intensive mixer, and the roasting device comprises a belt roasting machine or a grate.
In the embodiment of the invention, the granulating device and the roasting device both adopt the existing equipment, and the belt type roasting machine or the grate machine replaces the traditional circulating fluidized bed or a two-stage rotary kiln, so that the defects of poor process stability, complex process and incapability of treating powder ore below 1mm of the existing smelting reduction iron-making process pretreatment device are overcome, the yield of the smelting reduction furnace is improved, and the production cost is reduced.
As an optional implementation manner, the iron-containing material bin, the pulverized coal bin and the flux bin are respectively used for storing iron-containing materials, pulverized coal and fluxes.
Hereinafter, a method and an apparatus for pretreating a raw material for use in a smelting reduction iron making according to the present invention will be described in detail with reference to examples, comparative examples, and experimental data.
Example 1
As shown in fig. 2, the raw material pretreatment device for smelting reduction iron making in this embodiment includes an iron-containing material bin 1, a pulverized coal bin 2, a flux bin 3, a mixing device 4, a granulating device 5, a distributing machine 6, and a roasting device 7, where discharge ports of the iron-containing material bin 1, the pulverized coal bin 2, and the flux bin 3 are all connected to a feed port of the mixing device 4, a discharge port of the mixing device 4 is connected to a feed port of the granulating device 5, a discharge port of the granulating device 5 is connected to a feed port of the roasting device 7 through the distributing machine 6, one example of the roasting device 7 close to the feed port is a drying zone 71, and the other side is a pre-reduction zone 72, and a discharge port of the roasting device 7 is used for connecting to a feed system of a smelting reduction furnace.
Optionally, the granulating device 5 includes any one of a disk pelletizer, a cylinder pelletizer and an intensive mixer, and the roasting device 7 includes a belt roasting machine or a grate.
Optionally, the iron-containing material bin 1, the pulverized coal bin 2 and the flux bin 3 are respectively used for storing iron-containing materials, pulverized coal and flux.
Example 2
Based on the raw material pretreatment apparatus of embodiment 1, the present embodiment provides a raw material pretreatment method for smelting reduction iron making:
mixing refined iron powder (TFe 58%), coal powder (fixed carbon 76%) and dolomite according to the ratio of 100: 30: 6Mixing in 4, granulating in 5, spraying saturated Ca (OH) 8% of the total weight of the raw materials2Granulating the solution to obtain 2-6 mm of carbon-containing prefabricated granule raw materials;
uniformly distributing the carbon-containing prefabricated granular raw materials into a roasting device 7 by a material distributor 6, wherein the thickness of a material layer is 250 mm;
the temperature of the drying zone of the roasting device is 200 ℃, and the retention time of the materials in the drying zone is 12 min; the temperature of the pre-reduction area is 1000 ℃, the material stays for 18min, and the carbon-containing prefabricated granular clinker is obtained.
The moisture content of the dried carbon-containing prefabricated granulated clinker is below 3 percent, and the iron reduction rate in the iron fine powder in the carbon-containing prefabricated granulated clinker after pre-reduction is 43 percent.
Example 3
Based on the raw material pretreatment apparatus of embodiment 1, the present embodiment provides a raw material pretreatment method for smelting reduction iron making:
mixing blast furnace gas ash (TFe 51%), coal powder (fixed carbon 73%) and limestone in a mixing device 4 according to the proportion of 100: 15: 5, feeding into a granulating device 4, and spraying saturated Ca (OH) accounting for 5% of the total mass of raw materials2Granulating the solution to obtain 2-6 mm of carbon-containing prefabricated granule raw materials;
uniformly distributing the carbon-containing prefabricated granular raw materials into a roasting device 7 by a material distributor 6, wherein the thickness of a material layer is 500 mm;
the temperature of the drying zone of the roasting device 7 is 300 ℃, and the retention time of the materials in the drying zone is 6 min; the temperature of the pre-reduction area is 1100 ℃, the retention time of the materials is 10min, and the carbon-containing prefabricated granular clinker is obtained.
The moisture content of the dried carbon-containing prefabricated granulated clinker is below 3 percent, and the reduction rate of iron in blast furnace gas ash in the carbon-containing prefabricated granulated clinker after pre-reduction is 58 percent.
Example 4
Based on the raw material pretreatment apparatus of embodiment 1, the present embodiment provides a raw material pretreatment method for smelting reduction iron making:
mixing copper smelting slag (TFe 47%), coal powder (fixed carbon 81%), dolomite and limestone mixture (1: 1) in a mixing device 4 according to the ratio of 100: 21: 8, feeding the mixture into a granulating device 5, and spraying raw materials3% of total mass of saturated Ca (OH)2Granulating the solution to obtain 2-6 mm of carbon-containing prefabricated granule raw materials;
uniformly distributing the carbon-containing prefabricated granular raw materials into a roasting device 7 by a material distributor 6, wherein the thickness of a material layer is 100 mm;
the temperature of the drying zone of the roasting device is 150 ℃, and the retention time of the materials in the drying zone is 8 min; the temperature of the pre-reduction area is 850 ℃, the material stays for 30min, and the carbon-containing prefabricated granular clinker is obtained.
The moisture content of the dried carbon-containing prefabricated granulated clinker is below 3 percent, and the reduction rate of iron in copper smelting slag in the carbon-containing prefabricated granulated clinker after pre-reduction is 36 percent.
It can be seen that the reduction rate of the carbon-containing prefabricated granular clinker in the embodiment 2-4 is 36-58%, which is much higher than that of the rotary kiln, and the stability and maturity of the belt type roasting machine or the grate machine are obviously superior to those of a circulating fluidized bed, so that the defects that the existing pretreatment device and process are poor in stability, complex in process and incapable of treating ore fines below 1mm are overcome.
One or more technical solutions in the embodiments of the present invention at least have the following technical effects or advantages:
(1) the embodiment of the invention provides a raw material pretreatment method for smelting reduction ironmaking, which is characterized in that coal powder is added into raw materials of a smelting reduction ironmaking process, the coal powder is used as a reducing substance, the defect of low content of reducing gas in coal gas of a smelting reduction furnace can be effectively overcome, so that the reduction degree of an iron-containing material is improved in a pre-reduction reaction, the reduction rate of the iron-containing material in the obtained carbon-containing prefabricated granular clinker can reach 30-60%, the iron-containing material is used as a raw material for smelting reduction ironmaking, the smelting load of the smelting reduction furnace can be greatly reduced, the yield of the smelting reduction furnace is improved, wherein the mass ratio of the iron-containing material, the coal powder and a flux is controlled to be 100: 15-30: 5-8, the reduction degree of the iron-containing material is favorably and fully improved, and incomplete combustion of the coal powder in the reduction, the coal powder has low mass ratio, so that the reducing atmosphere is insufficient during reduction roasting, the reduction rate is low, the heat supply of a smelting reduction furnace and the carburization of molten iron are insufficient, the smelting efficiency and the quality of the molten iron are reduced, the flux is added to control the binary alkalinity of slag in the smelting reduction furnace to be 1.1-1.4, and the alkalinity of the slag is increased and the amount of the slag is increased when the flux is too high; too low results in an increase in the melting point of the slag system, both of which result in an increase in coal consumption.
(2) The invention embodiment relates to a raw material pretreatment device for smelting reduction ironmaking, which is characterized in that an iron-containing material bin, a coal powder bin and a flux bin are respectively used for storing iron-containing materials, coal powder and flux, the iron-containing materials, the coal powder and the flux enter a mixing device to be uniformly mixed to obtain a mixed material, the mixed material enters a granulating device to be granulated to obtain carbon-containing prefabricated grain raw meal, the carbon-containing prefabricated grain raw meal is uniformly distributed to a drying zone of a roasting device through a distributing machine to be dried and then enters a pre-reduction zone of the roasting device to be pre-reduced, and the obtained carbon-containing prefabricated grain clinker is used as a raw material for smelting reduction reaction. And the roasting devices such as a belt type roasting machine or a chain grate machine and the like are used for replacing the traditional circulating fluidized bed or a two-stage rotary kiln, thereby overcoming the defects of poor process stability, complex process and incapability of treating ore fines below 1mm in the conventional smelting reduction iron-making process.
Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A method of pretreating a raw material for use in smelting reduction ironmaking, the method comprising:
mixing iron-containing materials, coal powder and a fusing agent according to a mass ratio of 100: (15-30): (5-8) mixing to obtain a mixed material;
granulating the mixed material to obtain a carbon-containing prefabricated granule raw material;
and drying the carbon-containing prefabricated grain raw material, and then carrying out pre-reduction reaction to obtain the carbon-containing prefabricated grain clinker.
2. The raw material pretreatment method for smelting reduction ironmaking according to claim 1, characterized in that the iron-containing material comprises at least one of iron ore powder, iron-containing dust and sludge of iron and steel works and iron-containing nonferrous metallurgy slag, the content of TFe in the iron-containing material is not less than 45%, and the particle size of the iron-containing material is 0-2 mm.
3. The raw material pretreatment method for smelting reduction ironmaking according to claim 1, characterized in that the fixed carbon content in the pulverized coal is not less than 70%, and the particle size of the pulverized coal is 0-2 mm.
4. A method of pre-treating a raw material for a smelting reduction iron-making according to claim 1, wherein the flux comprises dolomite and/or limestone, and the flux has a particle size of 0 to 1 mm.
5. The method as claimed in claim 1, wherein the granulating of the mixed material to obtain the carbon-containing pre-granulated raw material comprises:
will be described inThe mixture is granulated by spraying atomized saturated Ca (OH)2Solution of said saturated Ca (OH)2And spraying the solution into the mixture, wherein the mass of the solution is 3-8% of that of the mixed material, and thus obtaining the carbon-containing prefabricated granular raw material with the granularity of 2-6 mm.
6. The method as claimed in claim 1, wherein the pre-treatment of raw materials for smelting reduction iron making comprises drying the carbon-containing pre-granulated raw meal, and performing pre-reduction reaction to obtain the carbon-containing pre-granulated clinker, which comprises:
and drying the carbon-containing prefabricated granular raw materials, introducing the coal gas generated by the smelting reduction iron-making reaction and subjected to dust removal and purification to perform a pre-reduction reaction, wherein the air-fuel ratio is 0.8-1.0, the reaction temperature is 800-1100 ℃, and the reaction time is 10-30 min, so as to obtain the carbon-containing prefabricated granular clinker.
7. The method as claimed in claim 6, wherein the drying of the carbonaceous pre-granulated raw meal comprises:
and (3) distributing the carbon-containing prefabricated granular raw material, wherein the thickness of a material layer is 200-600 mm, drying at 150-300 ℃ for 5-15 min, and taking a drying heat source as smoke generated by the pre-reduction reaction.
8. A raw material pretreatment device for smelting reduction ironmaking is characterized by comprising an iron-containing material bin (1), a pulverized coal bin (2), a flux bin (3), a mixing device (4), a granulating device (5), a distributing machine (6) and a roasting device (7), the discharge holes of the iron-containing material bin (1), the pulverized coal bin (2) and the flux bin (3) are all connected with the feed inlet of the mixing device (4), the discharge hole of the mixing device (4) is connected with the feed inlet of the granulating device (5), the discharge hole of the granulating device (5) is connected with the feed inlet of the roasting device (7) through the distributing machine (6), one side of the roasting device (7) close to the feed inlet is a drying area (71), the other side is a pre-reduction area (72), and the discharge hole of the roasting device (7) is used for being connected with a feeding system of the smelting reduction furnace.
9. A raw material pretreatment apparatus for melt reduction iron-making according to claim 8, wherein said granulation apparatus (5) comprises any one of a disk pelletizer, a drum pelletizer and an intensive mixer, and said roasting apparatus (7) comprises a belt type roasting machine or a grate.
10. A raw material pretreatment apparatus for smelting reduction ironmaking according to claim 8, characterized in that said iron-containing material silo (1), said pulverized coal silo (2) and said flux silo (3) are used for storing iron-containing material, pulverized coal and flux, respectively.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101935794A (en) * | 2010-10-11 | 2011-01-05 | 北京科技大学 | Method for producing ferro-nickel alloy by using nickel-bearing laterite in shaft furnace and smelting furnace |
| CN104004905A (en) * | 2013-02-27 | 2014-08-27 | 宝山钢铁股份有限公司 | Production process for metalized burden suitable for blast furnace ironmaking |
| CN104498656A (en) * | 2014-12-15 | 2015-04-08 | 钢铁研究总院 | Method for smelting iron by directly melting and reducing powdered ore |
| CN105695850A (en) * | 2016-04-18 | 2016-06-22 | 攀钢集团攀枝花钢铁研究院有限公司 | Utilization method of nickel-contained iron ore |
| CN105695653A (en) * | 2016-03-25 | 2016-06-22 | 首钢总公司 | Production method and system for prereduction iron-containing furnace burden |
-
2021
- 2021-03-09 CN CN202110248845.2A patent/CN113122708A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101935794A (en) * | 2010-10-11 | 2011-01-05 | 北京科技大学 | Method for producing ferro-nickel alloy by using nickel-bearing laterite in shaft furnace and smelting furnace |
| CN104004905A (en) * | 2013-02-27 | 2014-08-27 | 宝山钢铁股份有限公司 | Production process for metalized burden suitable for blast furnace ironmaking |
| CN104498656A (en) * | 2014-12-15 | 2015-04-08 | 钢铁研究总院 | Method for smelting iron by directly melting and reducing powdered ore |
| CN105695653A (en) * | 2016-03-25 | 2016-06-22 | 首钢总公司 | Production method and system for prereduction iron-containing furnace burden |
| CN105695850A (en) * | 2016-04-18 | 2016-06-22 | 攀钢集团攀枝花钢铁研究院有限公司 | Utilization method of nickel-contained iron ore |
Non-Patent Citations (2)
| Title |
|---|
| 朱苗勇等: "《现代冶金工艺学 钢铁冶金卷》", 31 December 2016, 冶金工业出版社 * |
| 陈津等: "自熔性烧结含碳球团研究", 《钢铁》 * |
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