阅读说明：本技术 一种改性的物性重构钢渣微粉制备装置及应用方法 (Modified physical property reconstructed steel slag micro powder preparation device and application method ) 是由 袁章福 王容岳 于湘涛 刘克 施春红 廖亮 于 2020-12-29 设计创作，主要内容包括：本发明涉及一种改性的物性重构钢渣微粉制备装置及应用方法,制备装置包括填料室、离心外场碳化炉、余热回收系统、回收磷粉系统和粉磨-磁选多力场耦合调控装置；离心外场碳化炉包括进料斗、出料口和挡料板,进料斗与所述填料室连接,出料口与所述余热回收系统连接；余热回收系统分别与所述回收磷粉系统和粉磨-磁选多力场耦合调控装置连接。本发明的制备装置利用离心外场增大反应界面,加速钢渣物相重构和元素迁移动力学,采用多力场耦合调控实现多组份高效分离,改性的物性重构钢渣微粉用于喷吹进入高炉,不仅作为二次能源得以利用,变废为宝,而且为杜绝废渣占地,治理环境污染创造了条件,对废渣循环利用及节约能源具有重要意义。(The invention relates to a preparation device and an application method of modified physical property reconstructed steel slag micro powder, wherein the preparation device comprises a packing chamber, a centrifugal external field carbonization furnace, a waste heat recovery system, a phosphorus powder recovery system and a grinding-magnetic separation multi-force field coupling regulation and control device; the centrifugal outfield carbonization furnace comprises a feed hopper, a discharge port and a baffle plate, wherein the feed hopper is connected with the packing chamber, and the discharge port is connected with the waste heat recovery system; and the waste heat recovery system is respectively connected with the phosphorus powder recovery system and the grinding-magnetic separation multi-force field coupling regulation and control device. The preparation device provided by the invention utilizes a centrifugal external field to increase a reaction interface, accelerates phase reconstruction and element migration dynamics of the steel slag, realizes high-efficiency separation of multiple components by adopting multi-force field coupling regulation, and the modified physical reconstructed steel slag micro powder is used for blowing into a blast furnace, so that the modified physical reconstructed steel slag micro powder is utilized as secondary energy, waste is turned into wealth, conditions are created for stopping occupation of land by waste slag and treating environmental pollution, and the preparation device has important significance for recycling waste slag and saving energy.)

1. A modified physical property reconstructed steel slag micro-powder preparation device is characterized by comprising a packing chamber, a centrifugal external field carbonization furnace, a waste heat recovery system, a phosphorus powder recovery system and a grinding-magnetic separation multi-force field coupling regulation and control device;

the centrifugal outfield carbonization furnace comprises a feed hopper, a discharge hole and a material baffle plate;

the feed hopper is connected with the filling chamber, and the discharge port is connected with the waste heat recovery system;

the waste heat recovery system is respectively connected with the phosphorus powder recovery system and the grinding-magnetic separation multi-force field coupling regulation and control device;

the grinding-magnetic separation multi-force field coupling regulation and control device comprises a feed hopper, a shearing force field system, a material receiving slideway and an electromagnetic disc magnetic separator.

2. The apparatus for preparing modified physically-reconstructed steel slag micropowder according to claim 1, wherein the feed hopper is connected to the shear force field system, and the electromagnetic disk magnetic separator adopts a high-gradient magnetic separation technology.

3. The apparatus for preparing modified physical reconstruction steel slag micropowder according to claim 1, characterized in that: the shearing force field system comprises a discharging connecting plate and crushing teeth.

4. The apparatus for preparing modified physically reconstructed steel slag micropowder according to any one of claims 1 to 3, wherein the electromagnetic disk magnetic separator is provided with a magnetic material receiving disk, a non-magnetic material receiving disk and a belt pulley.

5. The method for preparing the modified physical reconstructed steel slag micropowder by using the preparation device as claimed in any one of claims 1 to 4, which is characterized by comprising the following steps:

(1) mixing the steel slag, a reducing agent, an additive and a binder to prepare a mixture, adding the mixture into a centrifugal external field carbonization furnace through a packing chamber, and adopting a centrifugal external field enhanced carbon thermal reduction mode to ensure that high-valence weak-magnetic iron Fe in the steel slag₂O₃To lower valence iron FeO and Fe₃O₄And Fe conversion of elementary substance Fe, and high valence phosphorus P₂O₅Converting the phosphorus P into elemental phosphorus P to obtain high-temperature primarily modified physical property reconstructed steel slag;

(2) loading the high-temperature preliminarily modified physical reconstructed steel slag into a waste heat recovery system for waste heat recovery, removing simple substance phosphorus in the waste heat recovery system, and simultaneously obtaining the cooled modified physical reconstructed steel slag;

(3) cutting and grinding the cooled modified physical property reconstructed steel slag obtained in the step (2) by adopting a vertical grinding and superfine ball milling two-stage technology to obtain the steel slag containing Fe₃O₄The modified physical properties of Fe and FeO reconstruct the steel slag micro powder;

(4) adopting a high-gradient magnetic separation technology to efficiently separate the modified physical reconstructed steel slag micro powder obtained in the step (3) to obtain the steel slag micro powder with Fe and Fe removed₃O₄The modified physical property reconstructed steel slag micro powder.

6. The method for preparing the modified physically-reconstructed steel slag micropowder according to claim 5, wherein the reducing agent in the step (1) is at least one of coal gangue, coal powder and carbon powder; the additive is at least one of calcium carbonate and magnesium carbonate; the binder is bentonite.

7. The method for preparing the modified physically-reconstructed steel slag micropowder according to claim 5, wherein the temperature of the carbothermic reduction roasting treatment of the centrifugal outfield carbonization furnace in the step (1) is 1300-1500 ℃; the roasting time is 15-30 minutes.

8. A method of blowing blast furnace using modified physically reconstructed steel slag micropowder, characterized in that the modified physically reconstructed steel slag micropowder is prepared by the method of any one of claims 5 to 7, and is blown into a blast furnace together with fine coal powder from a tuyere to remove a slag layer in the blast furnace.

9. The method for blowing the blast furnace by using the modified physically reconstructed steel slag micro powder according to claim 8, wherein the mass ratio of the modified physically reconstructed steel slag micro powder to the fine coal powder is 0.8-1.2.

10. The method of claim 8, wherein the amount of the modified physically reconstructed steel slag micropowder blown into the blast furnace is 10 to 30kg per ton of molten iron.

Technical Field

The invention belongs to the field of comprehensive recycling of metallurgical slag resources, and particularly relates to a preparation device and an application method of modified physical-property reconstructed steel slag micro powder.

Background

In the prior art, the amount of steel slag discharged correspondingly is continuously increased along with the continuous rising of the yield of steel. The crude steel yield of the Chinese continental is 9.963 hundred million tons in 2019, accounts for 53.3 percent of the global crude steel yield, and is the first place of the world. About 15% of steel slag is produced per ton of converter steel, the quantity of the steel slag per year is about 1.2 hundred million tons, the accumulated stock exceeds 18 million tons by 2019 years according to incomplete statistics, and the effective utilization rate of the traditional Chinese steel slag is only about 30%, so that resources are wasted, a large amount of cultivated land is occupied, and environmental pollution is caused.

The internal circulation of steel smelting and the preparation of building materials are two main approaches for the conversion and utilization of the current steel slag: harmful phosphorus elements in the steel slag in the metallurgy internal recycling process are easy to be enriched in a blast furnace, the dephosphorization pressure in the steel-making process is increased, and a phosphorus-rich phase (P2O5) in the slag is easy to be combined with a basic metal oxide in the high-temperature calcination process to prepare a phosphate phase, so that the mechanical property of the steel slag-based material is seriously influenced.

During the converter steelmaking process, a large amount of high-temperature molten steel slag is generated, the temperature is as high as about 1600 ℃, the specific heat capacity of the slag is about 1.2J/(kg.cndot.), and the sensible heat contained in each ton of slag is about equivalent to the heat generated after 50-70kg of standard coal is completely combusted. If the sensible heat of the part of the slag can be recovered, the total energy saving amount can reach 600 ten thousand tons of standard coal. Because the sensible heat utilization rate of the steel slag is low in cost problem, huge waste of heat energy is caused, the sensible heat of the steel slag is fully utilized, and the method has important significance for realizing efficient utilization of resources and energy and reducing energy conservation and consumption reduction of iron and steel enterprises.

Disclosure of Invention

The invention aims to provide a preparation device and an application method of modified physical property reconstructed steel slag micro powder, which aim to solve the problems in the prior art.

The invention provides a modified physical property reconstructed steel slag micro-powder preparation device, which comprises a packing chamber, a centrifugal external field carbonization furnace, a waste heat recovery system, a phosphorus powder recovery system and a grinding-magnetic separation multi-force field coupling regulation and control device, wherein the centrifugal external field carbonization furnace is arranged in the packing chamber; the centrifugal outfield carbonization furnace comprises a feed hopper, a discharge port and a material baffle plate, wherein the feed hopper is connected with the packing chamber, and the discharge port is connected with the waste heat recovery system; the waste heat recovery system is respectively connected with the phosphorus powder recovery system and the grinding-magnetic separation multi-force field coupling regulation and control device, and the grinding-magnetic separation multi-force field coupling regulation and control device comprises a feed hopper, a shearing force field system, a material receiving slideway and an electromagnetic disc magnetic separator.

Further, the feed hopper is connected to the shear force field system.

Further, the shear force field system comprises a discharge connecting plate and crushing teeth.

Furthermore, the electromagnetic disc magnetic separator is provided with a magnetic material receiving disc, a non-magnetic material receiving disc and a belt pulley.

Further, the method for preparing the modified physical reconstructed steel slag micro powder by adopting the preparation device comprises the following steps:

(1) mixing steel slag, a reducing agent, an additive and a binder to prepare a mixture, adding the mixture into a centrifugal external field carbonization furnace through a filling chamber, and converting high-valence weak magnetic iron Fe2O3 in the steel slag into low-valence iron FeO, Fe3O4 and iron elementary substance Fe and converting high-valence phosphorus P2O5 into elementary substance P by adopting a centrifugal external field enhanced carbothermic reduction mode to obtain high-temperature primarily modified physical property reconstructed steel slag;

(2) loading the high-temperature preliminarily modified physical reconstructed steel slag into a waste heat recovery system for waste heat recovery, removing simple substance phosphorus in the waste heat recovery system, and simultaneously obtaining the cooled modified physical reconstructed steel slag;

(3) cutting and grinding the cooled modified physical reconstructed steel slag obtained in the step (2) by adopting a vertical grinding and superfine ball milling two-stage technology to obtain modified physical reconstructed steel slag micro powder comprising Fe3O4, Fe and FeO;

(4) and (3) carrying out high-efficiency separation on the modified physical reconstructed steel slag micro powder obtained in the step (3) by adopting a high-gradient magnetic separation technology to obtain the modified physical reconstructed steel slag micro powder with Fe and Fe3O4 removed.

Further, the reducing agent in the step (1) is at least one of coal gangue, coal powder and carbon powder; the additive is at least one of calcium carbonate and magnesium carbonate; the binder is bentonite.

Further, the temperature of the centrifugal external field carbonization furnace carbon thermal reduction roasting treatment in the step (1) is 1300-1500 ℃; the roasting time is 15-30 minutes.

Further, a method of blowing into a blast furnace by using modified physically reconstructed steel slag micro powder containing FeO, which is blown into the blast furnace together with fine coal powder from a tuyere, to remove a slag layer in the blast furnace.

Further, the mass ratio of the modified physical reconstructed steel slag micro powder to the fine coal powder is 0.8-1.2.

Furthermore, the blowing amount of the modified physical reconstructed steel slag micro powder is 10-30 kg per ton of molten iron.

The invention has the advantages of

The modified physical property reconstructed steel slag micro powder preparation device has the following beneficial effects:

1. the centrifugal external field is utilized to enlarge a reaction interface, accelerate steel slag phase reconstruction and element migration dynamics, and multi-component efficient separation is realized by adopting multi-force field coupling regulation.

2. The modified physical property reconstructed steel slag micro powder prepared by the invention not only can be used as secondary energy to change waste into valuable, but also creates conditions for stopping waste slag occupation and treating environmental pollution, and has important significance for recycling waste slag and saving energy.

3. The modified physical reconstructed steel slag micro powder is used as a viscosity remover of the blast furnace, and the ferrous oxide FeO contained in the modified physical reconstructed steel slag micro powder is utilized to enable a viscous slag layer which is difficult to flow in the blast furnace to become smooth and easy to drop, so that the thickness of the slag layer at the periphery of a blast furnace tuyere convolution area is thinned, the air permeability in the blast furnace is improved, and the cost can be reduced because the air permeability of the blast furnace is improved and the coke consumption is reduced.

Drawings

FIG. 1 is a schematic structural view of a modified physical-property reconstructed steel slag micro-powder preparation device;

FIG. 2 is a schematic structural diagram of the centrifugal outfield carbonizing furnace according to the present invention;

FIG. 3 is a schematic structural view of the powder grinding-magnetic separation multi-force field coupling regulation and control device of the present invention.

In the figure: 1-a filling chamber, 2-a centrifugal external field carbide furnace, 201-a feeding hopper, 202-a material baffle, 203-a furnace body, 204-a slag mixture, 205-a discharging port, 3-a waste heat recovery system, 4-a phosphorus powder recovery system, 5-grinding-magnetic separation multi-force-field coupling regulation and control device, 501-a feeding hopper, 502-a shearing force field system, 503-a magnetic material receiving disc, 504-a discharging connecting plate, 505-a belt pulley, 506-a non-magnetic material receiving disc, 507-a material receiving slideway, 508-an electromagnetic roller magnetic separator and 509-a crushing tooth.

Detailed Description

In order to better understand the technical solution of the present invention, the present disclosure includes but is not limited to the following detailed description, and similar techniques and methods should be considered as within the scope of the present invention. In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

It should be understood that the described embodiments of the invention are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

As shown in the figures 1-3, the invention provides a preparation device of modified physical reconstructed steel slag micro powder. The preparation device comprises a packing chamber 1, a centrifugal external field carbonization furnace 2, a waste heat recovery system 3, a phosphorus powder recovery system 4 and a grinding-magnetic separation multi-force field coupling regulation and control device 5; the centrifugal outfield carbonization furnace 2 comprises a feed hopper 201, a discharge port 205 and a material baffle 202, wherein the feed hopper 201 is connected with the packing chamber 1, and the discharge port 205 is connected with the waste heat recovery system 3; the waste heat recovery system 3 is respectively connected with a phosphorus powder recovery system 4 and a grinding-magnetic separation multi-force field coupling regulation and control device 5. The steel slag, the reducing agent, the additive and the binder are mixed to prepare a mixture 204, the mixture is added into a feed hopper 201 of a centrifugal outfield carbide furnace through a packing chamber 1, the mixture is subjected to a carbothermic reduction reaction of a centrifugal outfield carbide furnace 2 to obtain a high-temperature primarily modified physical reconstructed steel slag, the high-temperature primarily modified physical reconstructed steel slag is conveyed into a waste heat recovery system 3 connected with the high-temperature primarily modified physical reconstructed steel slag through a discharge port 205 to be subjected to waste heat recovery, high-valence phosphorus is converted into elemental phosphorus, and finally the phosphorus is converted into phosphorus steam to be volatilized and extracted in a phosphorus powder recovery system 4 connected with the waste heat recovery system 3, so that the cooled modified physical reconstructed steel slag containing Fe, Fe3O4 and FeO is obtained.

The grinding-magnetic separation multi-force field coupling regulation and control device 5 comprises a feed hopper 501, a shearing force field system 502, a material receiving slideway 507 and an electromagnetic disc magnetic separator 508. The feed hopper 501 is connected with a shearing force field system 502; the shearing force field system 502 is provided with a discharging connecting plate 504 and crushing teeth 509; the discharging connecting plate 504 is connected with an electromagnetic disk magnetic separator 508, and the electromagnetic disk magnetic separator 508 is provided with a magnetic material receiving disk 503, a non-magnetic material receiving disk 506 and a belt pulley 505; the belt pulley 505 is connected with a material receiving slideway 507; the material receiving slide 507 is connected with the magnetic material receiving tray 503. The modified physical reconstructed steel slag containing Fe, Fe3O4 and FeO enters a grinding-magnetic separation multi-force field coupling regulation and control device 5 from a feed hopper 501 for processing, wherein the modified physical reconstructed steel slag firstly enters a shearing force field system 502, the modified physical reconstructed steel slag is sheared and ground by a crushing tooth 509 arranged in the system by adopting a vertical grinding and superfine ball milling two-stage technology to obtain modified physical reconstructed steel slag micro powder, the micro powder is conveyed to an electromagnetic cylinder magnetic separator 508 from a discharge connecting plate 504 for magnetic separation, a low-valence iron component in the micro powder is efficiently separated by adopting a high-gradient magnetic separation technology, the non-magnetic micro powder is conveyed to a non-magnetic material receiving disc 506 through a belt pulley 505, the micro powder containing strong magnetic Fe and Fe3O4 is conveyed to a magnetic material receiving disc 503 through a material receiving chute 507 for processing, the ferromagnetic Fe and Fe3O4 substances are removed, and finally modified physical reconstructed steel slag micro powder containing a large amount of FeO is obtained in the non-magnetic substance receiving tray 506.

Preferably, a material baffle 202 is arranged inside a furnace body 203 of the centrifugal outfield carbonization furnace 2 for stirring the mixture 204.

The method for preparing the modified physical reconstructed steel slag micro powder comprises the following steps:

(1) mixing steel slag, a reducing agent, an additive and a binder to prepare a mixture, adding the mixture into a centrifugal external field carbonization furnace through a filling chamber, and converting high-valence weak magnetic iron Fe2O3 in the steel slag into low-valence iron FeO, Fe3O4 and iron elementary substance Fe and converting high-valence phosphorus P2O5 into elementary substance P by adopting a centrifugal external field enhanced carbothermic reduction mode to obtain high-temperature primarily modified physical property reconstructed steel slag;

(2) loading the high-temperature preliminarily modified physical reconstructed steel slag into a waste heat recovery system for waste heat recovery, removing simple substance phosphorus in the waste heat recovery system, and simultaneously obtaining the cooled modified physical reconstructed steel slag;

(3) cutting and grinding the cooled modified physical reconstructed steel slag obtained in the step (2) by adopting a vertical grinding and superfine ball milling two-stage technology so as to obtain modified physical reconstructed steel slag micro powder comprising Fe3O4, Fe and FeO;

(4) and (3) efficiently separating the modified physical reconstructed steel slag micro powder obtained in the step (3) by adopting a high-gradient magnetic separation technology to obtain the modified physical reconstructed steel slag micro powder with Fe and Fe3O4 removed, wherein the electromagnetic cylinder magnetic separator 508 generates a high-gradient magnetic field by adopting the high-gradient magnetic separation technology, and separates Fe and Fe3O4 with stronger magnetism in the modified physical reconstructed steel slag micro powder from the modified physical reconstructed steel slag micro powder to leave FeO with weaker magnetism.

Preferably, the reducing agent in the step (1) is at least one of coal gangue, coal powder and carbon powder; the additive is at least one of calcium carbonate and magnesium carbonate; the binder is bentonite.

Preferably, the conversion of high-valence phosphorus to elemental phosphorus in step (1) and the final conversion of phosphorus to phosphorus vapor are volatilized and extracted in the recovered phosphorus powder system 4.

Preferably, in the step (1), the centrifugal outfield carbonization furnace 2 is provided with a feed hopper 201 for feeding the mixture 204 and a discharge port 205 for discharging the high-temperature primarily modified physical reconstructed steel slag.

Preferably, the temperature of the carbon thermal reduction roasting treatment of the centrifugal external field carbonization furnace in the step (1) is 1300-1500 ℃; the roasting time is 15-30 minutes, the temperature range can enable the mixture to be in a molten state, and the roasting time range can enable the reducing agent to be fully utilized.

The magnetic field intensity of the electromagnetic cylinder magnetic separator 508 in the step (4) is 1000-1500 mT, wherein mT is a magnetic flux unit and represents milliTesla. The magnetic field intensity range can effectively and magnetically select magnetic Fe and Fe3O4 in the modified steel slag, and finally the modified physical reconstructed steel slag rich in FeO is obtained.

The invention also provides a method for blowing the blast furnace by using the modified physical reconstructed steel slag micro powder, the modified physical reconstructed steel slag micro powder obtained by the preparation method is mixed with fine coal powder and blown into the blast furnace from an air inlet of the blast furnace, the air permeability in the blast furnace is adjusted by using FeO in the modified physical reconstructed steel slag, and the use amount of coke used for keeping the air permeability can be reduced, so the cost can be reduced.

Iron making is carried out continuously in a blast furnace. Iron ore, coke, and a flux (limestone) for slag formation are charged from the top of the furnace, and preheated air is blown from tuyeres located at the lower part of the blast furnace along the periphery of the furnace (the blast furnace also blows auxiliary fuel such as fine coal powder, heavy oil, and natural gas). Carbon in the coke is combusted with oxygen blown into the air at a high temperature to generate carbon monoxide and hydrogen, and the carbon monoxide and the hydrogen are used for removing oxygen in the iron ore in the ascending process in the blast furnace, so that molten iron and other substances are obtained through reduction. In the reaction process, a slag layer with strong viscosity is generated in the deep part of a tuyere convolution area of a combustion zone in front of a blast furnace tuyere, the slag layer is called as a bird nest, and the slag layer on the periphery of the tuyere convolution area in the blast furnace becomes larger and larger along with the increase of the consumption of the fine coal powder. The modified physical reconstructed steel slag micro powder obtained by the invention has the advantages that ferrous oxide FeO effectively plays a role and chemically reacts with a slag layer, so that the viscous slag layer which is difficult to flow in the blast furnace becomes smooth and is easy to drip, and the thickness of the slag layer in a tuyere raceway in the blast furnace is thinned. In the preferred embodiment of the invention, the obtained modified physical reconstructed steel slag micro powder and the fine coal powder are simultaneously blown into the blast furnace, and the modified physical reconstructed steel slag micro powder and the slag layer at the convolute region of the blast furnace tuyere chemically react while the fine coal powder is combusted, so that the slag layer is prevented from accumulating on the inner wall of the blast furnace, and the air permeability in the blast furnace is improved.

Preferably, the mass ratio of the modified physical reconstructed steel slag micro powder to the fine coal powder is 0.8-1.2, and the mass ratio can effectively improve the air permeability in the blast furnace and reduce the using amount of coke.

Preferably, the modified physical reconstructed steel slag micro powder is blown in an amount of 10 to 30kg per ton of molten iron, that is, the blowing amount in the production of one ton of molten iron, thereby reducing the coke ratio by 6 to 10 kg.

According to the invention, by controlling the proportion of the steel slag, the reducing agent, the additive and the binder, phosphorus in the steel slag is reduced into a phosphorus simple substance and recovered in a form of phosphorus steam volatilization in the reducing atmosphere of the reducing roasting process of the mixture, and then the dephosphorized reduction product is subjected to shear force-magnetic force multi-force field coupling regulation and control to realize multi-component efficient separation.

The invention will now be described with reference to specific examples, which are intended to be illustrative only and not to be limiting in any way.

Example 1

The steel slag, the coal gangue, the calcium carbonate and the bentonite are steel slag according to the mass ratio: coal gangue: calcium carbonate: bentonite 100: 33: 15: 5, placing the steel slag into a centrifugal external field carbonization furnace, carrying out reduction roasting by adopting a centrifugal external field reinforced carbon thermal reduction mode, wherein the roasting temperature is 1300 ℃, the roasting time is 30min, obtaining a dephosphorized reduction product, carrying out waste heat recovery in the cooling process of the reduction product, then carrying out high-efficiency separation by vertical grinding and superfine ball milling two-stage technology grinding and a high-current high-magnetic technology with the magnetic field intensity of 1000mT, wherein the blowing-in amount of the steel slag micro powder after magnetic separation is 10kg/tFe, and the steel slag micro powder and the fine coal powder are steel slag micro powder according to the mass ratio: fine coal powder 0.8: 1, mixing and carrying out blast furnace blowing.

Example 2

The steel slag, the coal gangue, the calcium carbonate and the bentonite are steel slag according to the mass ratio: coal gangue: calcium carbonate: bentonite 100: 33: 15: 5, placing the steel slag into a centrifugal external field carbonization furnace, carrying out reduction roasting by adopting a centrifugal external field reinforced carbon thermal reduction mode, wherein the roasting temperature is 1400 ℃, the roasting time is 20min, obtaining a dephosphorized reduction product, carrying out waste heat recovery in the cooling process of the reduction product, then carrying out high-efficiency separation by vertical grinding and superfine ball milling two-stage technology grinding and a high-current high-magnetic technology with the magnetic field intensity of 1200mT, wherein the blowing-in amount of the steel slag micro powder after magnetic separation is 15kg/tFe, and the steel slag micro powder and the fine coal powder are the steel slag micro powder according to the mass ratio: 1 of fine coal powder: 1, mixing and carrying out blast furnace blowing.

Example 3

The steel slag, the coal powder, the calcium carbonate and the bentonite are steel slag according to the mass ratio: coal powder: magnesium carbonate: bentonite 100: 23: 18: 5, placing the steel slag into a centrifugal external field carbonization furnace, carrying out reduction roasting by adopting a centrifugal external field reinforced carbon thermal reduction mode, wherein the roasting temperature is 1400 ℃, the roasting time is 20min, obtaining a dephosphorized reduction product, carrying out waste heat recovery in the cooling process of the reduction product, then carrying out grinding by using a vertical mill and a superfine ball milling two-stage technology and carrying out high-efficiency separation by using a high-current high-magnetic technology with the magnetic field intensity of 1200mT, wherein the blowing-in amount of the steel slag micro powder after magnetic separation is 15kg/tFe, and the steel slag micro powder and the fine coal powder are the steel slag micro powder according to: 1 of fine coal powder: 1.2, mixing and carrying out blast furnace blowing.

Example 4

The steel slag, the carbon powder, the calcium carbonate and the bentonite are steel slag according to the mass ratio: carbon powder: calcium carbonate: bentonite 100: 33: 15: 5, placing the steel slag into a centrifugal external field carbonization furnace, carrying out reduction roasting by adopting a centrifugal external field reinforced carbon thermal reduction mode, wherein the roasting temperature is 1500 ℃, the roasting time is 15min, obtaining a dephosphorized reduction product, carrying out waste heat recovery in the cooling process of the reduction product, then carrying out high-efficiency separation by vertical grinding and superfine ball milling two-stage technology grinding and a high-current high-magnetic technology with the magnetic field intensity of 1300mT, wherein the blowing-in amount of the steel slag micro powder after magnetic separation is 20kg/tFe, and the steel slag micro powder and the fine coal powder are the steel slag micro powder according to the mass ratio: 1 of fine coal powder: 0.8, and performing blast furnace blowing. The foregoing description shows and describes several preferred embodiments of the invention, but as aforementioned, it is to be understood that the invention is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.