CN111471817A - Gas quenching method for improving stability of steel slag and recovering physical heat of molten steel slag - Google Patents
Gas quenching method for improving stability of steel slag and recovering physical heat of molten steel slag Download PDFInfo
- Publication number
- CN111471817A CN111471817A CN202010333009.XA CN202010333009A CN111471817A CN 111471817 A CN111471817 A CN 111471817A CN 202010333009 A CN202010333009 A CN 202010333009A CN 111471817 A CN111471817 A CN 111471817A
- Authority
- CN
- China
- Prior art keywords
- steel slag
- gas quenching
- gas
- slag
- molten steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 133
- 239000010959 steel Substances 0.000 title claims abstract description 133
- 239000002893 slag Substances 0.000 title claims abstract description 130
- 238000010791 quenching Methods 0.000 title claims abstract description 70
- 230000000171 quenching effect Effects 0.000 title claims abstract description 67
- 238000000034 method Methods 0.000 title claims abstract description 28
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 53
- 229910052742 iron Inorganic materials 0.000 claims abstract description 27
- 239000000843 powder Substances 0.000 claims abstract description 19
- 238000000227 grinding Methods 0.000 claims abstract description 8
- 238000007885 magnetic separation Methods 0.000 claims abstract description 6
- 239000007789 gas Substances 0.000 claims description 64
- 239000002245 particle Substances 0.000 claims description 31
- 239000010419 fine particle Substances 0.000 claims description 24
- 238000011084 recovery Methods 0.000 claims description 16
- 239000000428 dust Substances 0.000 claims description 13
- 239000007788 liquid Substances 0.000 claims description 13
- 238000012216 screening Methods 0.000 claims description 10
- 239000002918 waste heat Substances 0.000 claims description 10
- 239000000395 magnesium oxide Substances 0.000 claims description 8
- 229910052751 metal Inorganic materials 0.000 claims description 8
- 239000002184 metal Substances 0.000 claims description 8
- 230000009471 action Effects 0.000 claims description 5
- 238000004062 sedimentation Methods 0.000 claims description 5
- 239000008247 solid mixture Substances 0.000 claims description 5
- 238000009628 steelmaking Methods 0.000 claims description 5
- 238000003860 storage Methods 0.000 claims description 5
- 239000011362 coarse particle Substances 0.000 claims description 4
- 239000001095 magnesium carbonate Substances 0.000 claims description 4
- 229910000021 magnesium carbonate Inorganic materials 0.000 claims description 4
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 claims description 4
- 238000002844 melting Methods 0.000 claims description 4
- 230000008018 melting Effects 0.000 claims description 4
- 239000002912 waste gas Substances 0.000 claims description 2
- 230000008569 process Effects 0.000 abstract description 11
- 238000004064 recycling Methods 0.000 abstract description 10
- 238000000926 separation method Methods 0.000 abstract description 5
- 239000003034 coal gas Substances 0.000 abstract description 3
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 239000002910 solid waste Substances 0.000 abstract description 3
- 239000013543 active substance Substances 0.000 abstract 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 27
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 22
- 239000000292 calcium oxide Substances 0.000 description 11
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 11
- 239000001569 carbon dioxide Substances 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 7
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- 238000001816 cooling Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 229910000019 calcium carbonate Inorganic materials 0.000 description 3
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 3
- 239000002826 coolant Substances 0.000 description 3
- 230000001502 supplementing effect Effects 0.000 description 3
- 230000002349 favourable effect Effects 0.000 description 2
- 238000005469 granulation Methods 0.000 description 2
- 230000003179 granulation Effects 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000004566 building material Substances 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000029087 digestion Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- JEGUKCSWCFPDGT-UHFFFAOYSA-N h2o hydrate Chemical compound O.O JEGUKCSWCFPDGT-UHFFFAOYSA-N 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000006148 magnetic separator Substances 0.000 description 1
- 239000004579 marble Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 238000011020 pilot scale process Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 231100000817 safety factor Toxicity 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B3/00—General features in the manufacture of pig-iron
- C21B3/04—Recovery of by-products, e.g. slag
- C21B3/06—Treatment of liquid slag
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B3/00—General features in the manufacture of pig-iron
- C21B3/04—Recovery of by-products, e.g. slag
- C21B3/06—Treatment of liquid slag
- C21B3/08—Cooling slag
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2100/00—Handling of exhaust gases produced during the manufacture of iron or steel
- C21B2100/60—Process control or energy utilisation in the manufacture of iron or steel
- C21B2100/66—Heat exchange
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/02—Physical or chemical treatment of slags
- C21B2400/022—Methods of cooling or quenching molten slag
- C21B2400/026—Methods of cooling or quenching molten slag using air, inert gases or removable conductive bodies
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/08—Treatment of slags originating from iron or steel processes with energy recovery
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/10—Reduction of greenhouse gas [GHG] emissions
- Y02P10/122—Reduction of greenhouse gas [GHG] emissions by capturing or storing CO2
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
The invention relates to a gas quenching method for improving steel slag stability and recovering physical heat of molten steel slag, belonging to the environmental protection technical field of solid waste disposal, secondary resource recycling and the like in the metallurgical industry. The technical scheme is as follows: utilizing CO in a large amount of coal gas generated by iron and steel enterprises2The molten steel slag in the gas quenching chamber is subjected to gas quenching, and is subjected to grinding, fine magnetic separation and separation to obtain high-quality iron-rich powder and tailing powder, the secondary resource iron-rich powder can be fully utilized in various ways, and the tailing can be efficiently utilized as a high-quality secondary resource. And cold CO during gas quenching2Performing rapid heat exchange with molten slag, and converting the physical heat of the molten slag into CO2The physical heat is recycled by the heat exchange device, and the clean CO is dedusted2And (4) recycling. The invention comprehensively solves the problems of the reutilization of free active substances of the steel slag, the physical heat recycling of the steel slag and the like, and partially traps CO in the coal gas2The method has the advantages of realizing safe, efficient and environment-friendly steel slag quenching, sorting and recycling processes.
Description
Technical Field
The invention relates to a gas quenching method for improving steel slag stability and recovering physical heat of molten steel slag, belonging to the environmental protection technical field of solid waste disposal, secondary resource recycling and the like in the metallurgical industry.
Background
The steel slag is a large amount of solid waste generated in the steel industry, and the resource utilization of the steel slag is always strongly concerned by the society. From the initial extensive disposal modes of direct pouring, hot splashing, tray, iron selection, stacking and the like to the appearance of the new processes of hot stewing, rolling, multi-channel crushing and sorting, air quenching, rotary cup granulation and the like which are popular at present; the treatment and recycling of steel slag has been qualitatively changed from large land occupation caused by extensive treatment to fine recycling techniques. However, the current treatment methods still have some problems to different degrees. For example, steel slag is braised by heat, no matter what water supply cooling mode, a large amount of water is needed, and meanwhile, under the high-temperature condition, hydrogen generated by water vapor decomposition is easy to generate strong explosion after meeting air, so that non-safety factors exist; the steel slag after hot braising needs to be crushed and sorted for multiple times, the power consumption is higher, and even other superfine ground tailings still have some free calcium oxide or magnesium oxide to different degrees; the content of metal in the process slag is still higher. Air quenching is also a popular gas quenching mode at present, and water is required to be added for quenching in order to reduce free calcium oxide or magnesium oxide, so that the safety problem is also caused; in some technologies, nitrogen gas quenching is adopted, and physical heat of slag is recovered, but nitrogen has high cost, steel slag needs to be pre-modified to increase stability, and large-scale industrial application is not available; the roller method also has the problems of longer flow similar to the hot braising process, incomplete reutilization of tailings and the like. The rotary cup granulation is a new process which is developed and invested more in recent years, steel slag is quenched under the centrifugal force action of a rotary cup, and at present, certain difficulty is brought to large-scale treatment in a laboratory or a pilot-scale level, and some technical defects are not completely presented.
The technology for producing calcium carbonate by reacting lime water and carbon dioxide and extracting the calcium carbonate as a marble-based material is favorable at home and abroad. The technology is also referred to and proposed to introduce carbon dioxide into the emulsion of steel slag and water vapor or water, so that free calcium oxide is generated into calcium carbonate, the stability of the steel slag is improved, and the solidification of the carbon dioxide is realized.
Disclosure of Invention
The invention aims to provide a gas quenching method for improving the stability of steel slag and recovering physical heat of molten steel slag, which utilizes carbon dioxide to quench the steel slag into relatively uniform fine particles, is also a heat carrier and a reactant, realizes heat recovery and improves the stability of steel tailings, and solves the problems in the background art.
The technical scheme of the invention is as follows:
a gas quenching method for improving steel slag stability and recovering physical heat of molten steel slag comprises the following steps:
step I, conveying molten steel slag from a slag pot of a converter steelmaking system to a liquid steel slag ladle;
step II, flowing the molten steel slag in the liquid steel slag ladle to a gas quenching chamber through a steel slag chute, and flowing CO into the gas quenching chamber2The gas is quenched in a gas quenching chamber from a high-pressure storage tank through a pipeline, the gas quenching pressure is 0.25-0.65MPa, and the gas-liquid mass ratio is 1: 6-1: 12; the molten steel slag is rapidly cooled, and most of the molten steel slag is quenched into particles with the particle size of less than 3mm, the molten steel slag and low-temperature CO2Heat exchange is carried out, and simultaneously, free CaO, MgO and CO in the steel slag are simultaneously2Stabilized water-insoluble CaCO forming very fine particles3And MgCO3；
Step III, discharging the gas-solid mixture doped with metallic iron and slag fine particles, namely the iron-containing steel slag, from the upper part of the gas quenching chamber under the action of air force, and allowing the gas-solid mixture to enter a waste heat recovery device through a settling device, thereby realizing the physical heat recovery of molten steel slag, and simultaneously cooling CO2The waste gas is recycled after being dedusted and purified by a deduster;
IV, screening the iron-containing steel slag in the gas quenching chamber and the sedimentation device by using a screening device, and then feeding coarse particles with the particle size of more than or equal to 3mm into a mechanical crushing or fine grinding device to be crushed into particles with the particle size of less than 3 mm; and the screened particles with the size less than 3mm, the powder recovered by the waste heat recovery device and the powder collected by the dust remover enter a fine-particle steel slag collecting device, and the fine-particle powder and the powder of the mechanical crushing device pass through a magnetic separation separator to be separated into qualified metal iron or waste steel and qualified steel tailings.
In the step II, the molten steel slag is quenched into fine particles with the particle size of less than 3mm, and the fine particles are more than 85 percent; the particle size 100% after crushing or grinding is not more than 3 mm.
And the gas quenching starting temperature of the molten steel slag in the liquid steel slag ladle (2) in the step I is more than 20 ℃ higher than the melting point temperature of the steel slag.
The invention has the beneficial effects that:
1) the invention selects a scientific, simplified, environment-friendly and controllable process technical route, fully utilizes the physical heat of the molten steel slag, and comprehensively utilizes the carbon dioxide contained in the low-rank coal gas and the steel slag in the steel industry into a whole, and is safe, environment-friendly and efficient in the whole system.
2) The recycling of the carbon dioxide contained in the low-rank gas is based on the collection of the carbon dioxide based on the low-heat value gas generated by iron and steel enterprises such as blast furnace gas and the like, the improvement of the heat value of the gas and the realization of higher utilization value, and the problem of massive CO is solved2The problem of in-situ digestion and utilization is also a hot topic for reducing carbon emission in the steel industry at present;
3) the carbon dioxide provided by the invention has the functions in the system, not only can quench the steel slag into uniform fine particles, but also can be used as a heat carrier and a reactant, and can simultaneously realize heat recovery and improve the stability of the steel tailings in the system and improve the application range of the steel tailings;
4) the fine crushing and sorting and the high iron-containing resources generated in the process can be used as scrap steel to be added into an electric furnace or a blast furnace, or used as a coolant to be used for a converter; and ultrafine grinding and fine separation equipment can be additionally arranged according to actual requirements.
5) The invention uses carbon dioxide to replace water or air quenching, avoids unsafe factors existing in water quenching, and avoids the problems of secondary oxidation of air quenching metal iron and the like; meanwhile, the enthalpy of carbon dioxide is high, the amount of gas taking away the same heat is small, the process power consumption is low, and the extra consumption of carbon dioxide gas is relatively low due to the cyclic utilization of clean gas, so that the system economy can be improved;
6) the invention provides the environment-friendly technology model selection and design concept of the system, and the basic principles of no dust emission and ultra-low dust emission in the process are taken.
Drawings
FIG. 1 is a process flow diagram of the present invention;
in the figure: 1. CO 22A storage tank; 2. a liquid steel slag ladle; 3, a steel slag chute; 4, a gas quenching chamber; 5, a settling device; 6. a waste heat recovery device; 7, a dust remover; 8. a fine particle steel slag collecting device; a metal collector; 10. steel slag tailings; a magnetic separator; a crushing or fine grinding device; a screening device; 14. CO 22A replenishing device; 15. gas quenching of CO2A pressurized feeding device; CO 162And (4) supplementing the pipeline.
Detailed Description
The invention is further illustrated by way of example in the following with reference to the accompanying drawings.
Referring to the attached figure 1, a gas quenching method for improving the stability of steel slag and recovering the physical heat of molten steel slag comprises the following steps:
step I, conveying molten steel slag from a slag pot of a converter steelmaking system to a liquid steel slag ladle 2;
step II, flowing the molten steel slag in the liquid steel slag ladle 2 to a gas quenching chamber 4 through a steel slag chute 3, and introducing CO2The gas enters a gas quenching chamber 4 from a high-pressure storage tank through a pipeline for gas quenching, the gas quenching pressure is 0.35MPa, and the gas-liquid mass ratio is 1: 10; the molten steel slag is rapidly cooled, and most of the molten steel slag is quenched into particles with the particle size of less than 3mm, the molten steel slag and cold CO2Heat exchange is carried out, and simultaneously, free CaO, MgO and CO in the steel slag are simultaneously2Stabilized CaCO forming very fine particles3And MgCO3；
III, the gas-solid mixture of the iron-containing steel slag doped with the metallic iron and the fine slag particles in the gas quenching chamber 4 is discharged from the upper part of the gas quenching chamber 4 through the pneumatic action and enters the residual through a settling device 5The heat recovery device 6 realizes the physical heat recovery of the molten steel slag, and simultaneously, the cooled CO2The dust is removed and purified by a dust remover 7 and then recycled;
IV, screening the iron-containing steel slag in the gas quenching chamber 4 and the sedimentation device 5 by a screening device 13, and then feeding coarse particles with the particle size of more than or equal to 3mm into a mechanical crushing or fine grinding device 12 to be crushed into required particle size, namely, the particle size is less than-3 mm or finer; the screened particles smaller than 3mm, the powder recovered by the waste heat recovery device 6 and the powder collected by the dust remover 7 enter a fine-particle steel slag collecting device 8, and the fine-particle powder and the powder of the mechanical crushing device 12 pass through a magnetic separation device 11 to be separated into qualified metal iron 9 or scrap steel and qualified steel tailings 10.
In this embodiment, referring to fig. 1, a steel slag chute 3, a gas quenching chamber 4, a settling device 5, a waste heat recovery device 6, a dust remover 7, a fine steel slag collection device 8, a metal collector 9, a magnetic separation separator 11, a crushing device 12, a screening device 13, CO2Replenishing device 14 and gas quenching CO2The pressurized feeding device 15 is the content of the prior art, and further emphasizes that the gas quenching chamber 5 and the steel slag chute 3 are provided, wherein the gas quenching chamber 5 comprises a gas quenching nozzle and CO2Pressure and flow control and CO2A replenishing device and the like, wherein the gas quenching chamber 5 can ensure that the molten steel slag is quenched into fine particles with the particle size of less than 3mm and the particle size is more than 85 percent; secondly, sufficient heat exchange can be ensured, and most of physical heat of the steel slag is transferred into a gas-solid phase; meanwhile, the structure of the gas quenching chamber and the particle size of fine particles are controlled to ensure CO2And the free oxides CaO and MgO.
The steel slag chute 3 needs necessary heat preservation, and can adopt a chute mode in the form, and the angle can be adjusted within a certain range; the device can also be set into a mode similar to the pouring of a water gap of a continuous casting tundish, shortens the slag flow distance and time, and is favorable for smooth flow of slag.
A gas quenching method for improving steel slag stability and recovering physical heat of molten steel slag is operated according to the following method:
(1) steel slag transportation and temperature control: after tapping of the converter, molten steel slag is conveyed from a slag pot of a converter steel-making system to a receiving pot with heat preservation, automatic temperature rise and temperature control functions, the components and the temperature of the molten slag are measured on line, the melting point of the slag phase is calculated by using Factage commercial software, the fluidity characteristic is analyzed, and gas quenching is carried out under the condition that the temperature is not lower than the melting point and 35 ℃ according to the requirements of the components and the quenching granularity of the slag, so that the fluidity of the steel slag is ensured;
(2) gas quenching of steel slag: molten steel slag with good fluidity flows to a gas quenching chamber through a steel slag chute, and CO flows to the gas quenching chamber2From a high-pressure storage tank to a gas quenching nozzle through a pipeline, the pressure of the nozzle is 0.35MPa, the gas quenching nozzle enters a normal-pressure gas quenching chamber for gas quenching, and molten steel slag and low-temperature CO are obtained2Performing heat exchange with a gas-liquid ratio of 1:10, rapidly cooling the steel slag, and simultaneously quenching the steel slag into particles with a size of less than 3mm, wherein free CaO, MgO and CO in the steel slag are added2Stabilized CaCO forming very fine particles3And MgCO3. The gas quenching chamber is provided with CO2And the supplementing device is used for compensating the problem of low heat exchange caused by insufficient gas.
Related to CO2The reaction mechanism is similar to that of the free oxides CaO or MgO. For example, the gibbs free energy of CaO reaction becomes: Δ GCaO= -177860+160.44T-8.314RTlnPCO2. Such as CaO and CO at 1 atmosphere and less than 836 deg.C2The reaction of (3) can proceed. The temperature at which the theoretical reaction can proceed increases correspondingly with increasing pressure, which is advantageous for the reaction at higher temperatures. Therefore, according to the experimental research result and the actual operation condition, the pressure range of the gas quenching chamber is set to be 0.1-0.5 MPa (namely 1-5 atmospheric pressure) by considering factors such as economy and the like. The present embodiment selects a normal pressure state.
(3) And (3) waste heat recovery: the gas-solid mixture doped with metallic iron and slag fine particles is discharged from the upper part of the gas quenching chamber through pneumatic action, enters a waste heat recovery device through a settling chamber, and is subjected to high-temperature CO2The heat of the medium is exchanged, and the heat of the heat medium can be reused, thereby realizing the recycling of the physical heat of the molten steel slag. At the same time, the net CO after cooling2Recycling; CO in the system due to air leakage or chemical reaction2Loss, special setting of new CO2And (4) supplementing the pipeline.
(4) Slag-iron separation: a small amount of coarse-particle iron-containing steel slag can be generated in the gas quenching chamber and the sedimentation device, after being screened by the screening device, large particles enter the mechanical crushing device to be crushed into required particle size, and the separation efficiency of slag and iron is further improved through a fine grinding and slag and metal iron separation system; and after screening, the particles with the particle size of minus 3mm, the powder recovered by the waste heat recovery device and the powder collected by the dust remover enter a fine-particle steel slag collecting device, and all the fine-particle powder and the mechanically crushed powder with the particle size of minus 3mm pass through a magnetic separation separator to be separated into qualified waste steel and qualified steel slag. The steel slag and the scrap steel can be sold as products or reused in a steel generation system. The iron content of the tailings is less than or equal to 2 percent, and the tailings can be used for various ways such as building materials and the like. The scrap steel can be utilized according to grades of iron, for example, the iron content is more than 85 percent, the requirement of a steel-making coolant in a steel process is met, and the scrap steel can be directly used as the scrap steel or the coolant after being pressed into blocks; the low grade can be directly used for sintering.
In addition, in order to meet the requirement of environmental protection on unorganized emission control, the embodiment is provided with an environment dust removal auxiliary system and the like, dust pollution is strictly controlled in the production process, and dust emission in the production process reaches the standard.
Claims (3)
1. A gas quenching method for improving the stability of steel slag and recovering the physical heat of molten steel slag is characterized in that: the method comprises the following steps:
step I, conveying molten steel slag from a slag pot of a converter steelmaking system to a liquid steel slag ladle (2);
step II, flowing the molten steel slag in the liquid steel slag ladle (2) to a gas quenching chamber (4) through a steel slag chute (3), and flowing CO2Introducing the gas into a gas quenching chamber (4) from a high-pressure storage tank through a pipeline for gas quenching, wherein the gas quenching pressure is 0.25-0.65MPa, and the gas-liquid mass ratio is 1: 6-1: 12; the molten steel slag is rapidly cooled, and most of the molten steel slag is quenched into particles with the particle size of less than 3mm, the molten steel slag and low-temperature CO2Heat exchange is carried out, and simultaneously, free CaO, MgO and CO in the steel slag are simultaneously2Stabilized water-insoluble CaCO forming very fine particles3And MgCO3；
Step III, doping metal iron and slag fine particles in the gas quenching chamber (4)The gas-solid mixture of the iron-containing steel slag is discharged from the upper part of the gas quenching chamber (4) through pneumatic action and enters the waste heat recovery device (6) through the sedimentation device (5), thereby realizing the physical heat recovery of the molten steel slag, and simultaneously, the cooled CO2The waste gas is recycled after being dedusted and purified by a deduster (7);
IV, screening the iron-containing steel slag in the gas quenching chamber (4) and the sedimentation device (5) by a screening device (13), and then feeding coarse particles with the particle size of more than or equal to 3mm into a mechanical crushing or fine grinding device (12) to be crushed into particles with the particle size of less than 3 mm; the particles smaller than 3mm, the powder recovered by the waste heat recovery device (6) and the powder collected by the dust remover (7) enter a fine-particle steel slag collection device (8), and the fine-particle powder and the powder of the mechanical crushing device (12) are separated into qualified metallic iron or scrap steel (9) and qualified steel tailings (10) through a magnetic separation device (11).
2. The gas quenching method for improving the stability of steel slag and recovering the physical heat of molten steel slag according to claim 1, which is characterized in that: in the step II, the molten steel slag is quenched into fine particles with the particle size of less than 3mm, and the fine particles are more than 85%.
3. The gas quenching method for improving the stability of steel slag and recovering the physical heat of molten steel slag according to claim 1, which is characterized in that: the step I: the gas quenching starting temperature of the molten steel slag in the liquid steel slag ladle (2) is more than 20 ℃ higher than the melting point temperature of the steel slag.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010333009.XA CN111471817A (en) | 2020-04-24 | 2020-04-24 | Gas quenching method for improving stability of steel slag and recovering physical heat of molten steel slag |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010333009.XA CN111471817A (en) | 2020-04-24 | 2020-04-24 | Gas quenching method for improving stability of steel slag and recovering physical heat of molten steel slag |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111471817A true CN111471817A (en) | 2020-07-31 |
Family
ID=71764081
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010333009.XA Pending CN111471817A (en) | 2020-04-24 | 2020-04-24 | Gas quenching method for improving stability of steel slag and recovering physical heat of molten steel slag |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111471817A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112899420A (en) * | 2021-01-18 | 2021-06-04 | 山东大学 | Converter slag combined quenching alkali-removing magnetization heat recovery device and method |
| CN113149495A (en) * | 2021-05-26 | 2021-07-23 | 南京腾达环保科技有限公司 | By using CO-containing gas2Device and method for pretreating steel slag by tail gas air quenching |
| CN113789417A (en) * | 2021-09-28 | 2021-12-14 | 北京中航天业科技有限公司 | Atomization treatment device and treatment method for liquid steel slag |
| CN114573250A (en) * | 2022-02-24 | 2022-06-03 | 钢城集团凉山瑞海实业有限公司 | Air quenching method for preparing spherical particles from smelting slag |
| CN114657291A (en) * | 2022-03-24 | 2022-06-24 | 明正鹏达(天津)环保科技有限公司 | Device and method for quenching carbonized steel slag by using carbon dioxide |
| CN114890691A (en) * | 2022-05-09 | 2022-08-12 | 山东大学 | A kind of converter slag flue gas quenching and carbon solidification heat recovery device and method |
| CN115231316A (en) * | 2022-09-22 | 2022-10-25 | 山东大学 | Fluidized powder supply system and method based on waste gas and waste residue chilling steel slag |
| CN116460112A (en) * | 2023-03-09 | 2023-07-21 | 武汉钢铁有限公司 | Method and system for CO2 in steel slag mineralization flue gas |
| US12054795B2 (en) | 2022-09-22 | 2024-08-06 | Shandong University | System and method for delivering fluidized powder based on flue gas carrying waste slag and instant cooling steel slag |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06158124A (en) * | 1992-11-17 | 1994-06-07 | Nippon Steel Corp | Treatment of cooling steelmaking slag |
| CN101691620A (en) * | 2009-09-10 | 2010-04-07 | 河北理工大学 | Process and device for processing liquid steel slag |
| CN102952908A (en) * | 2012-10-15 | 2013-03-06 | 唐山钢铁国际工程技术有限公司 | Equipment for steel slag air quenching and waste heat recycling |
| KR20130046816A (en) * | 2011-10-28 | 2013-05-08 | 현대제철 주식회사 | Slag treatment apparatus and treatment method thereof |
| WO2013094861A1 (en) * | 2011-12-22 | 2013-06-27 | 주식회사 포스코 | Apparatus for reducing carbon dioxide by using molten slag |
| WO2017121694A1 (en) * | 2016-01-14 | 2017-07-20 | Thyssenkrupp Millservices & Systems Gmbh | Method of utilizing a steelworks slag, slag foam and use of a slag foam |
| CN110982967A (en) * | 2019-12-25 | 2020-04-10 | 江西理工大学 | Method and device for quenching steel slag and recovering waste heat by utilizing water and carbon dioxide |
-
2020
- 2020-04-24 CN CN202010333009.XA patent/CN111471817A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06158124A (en) * | 1992-11-17 | 1994-06-07 | Nippon Steel Corp | Treatment of cooling steelmaking slag |
| CN101691620A (en) * | 2009-09-10 | 2010-04-07 | 河北理工大学 | Process and device for processing liquid steel slag |
| KR20130046816A (en) * | 2011-10-28 | 2013-05-08 | 현대제철 주식회사 | Slag treatment apparatus and treatment method thereof |
| WO2013094861A1 (en) * | 2011-12-22 | 2013-06-27 | 주식회사 포스코 | Apparatus for reducing carbon dioxide by using molten slag |
| CN102952908A (en) * | 2012-10-15 | 2013-03-06 | 唐山钢铁国际工程技术有限公司 | Equipment for steel slag air quenching and waste heat recycling |
| WO2017121694A1 (en) * | 2016-01-14 | 2017-07-20 | Thyssenkrupp Millservices & Systems Gmbh | Method of utilizing a steelworks slag, slag foam and use of a slag foam |
| CN110982967A (en) * | 2019-12-25 | 2020-04-10 | 江西理工大学 | Method and device for quenching steel slag and recovering waste heat by utilizing water and carbon dioxide |
Non-Patent Citations (2)
| Title |
|---|
| 彭彝等: "热态钢渣CO2改性及热力学性能研究", 《环境工程》 * |
| 赵计辉等: "钢渣的体积安定性问题及稳定化处理的国内研究进展", 《硅酸盐通报》 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112899420A (en) * | 2021-01-18 | 2021-06-04 | 山东大学 | Converter slag combined quenching alkali-removing magnetization heat recovery device and method |
| CN112899420B (en) * | 2021-01-18 | 2022-02-25 | 山东大学 | Converter slag combined quenching alkali-removing magnetization heat recovery device and method |
| CN113149495A (en) * | 2021-05-26 | 2021-07-23 | 南京腾达环保科技有限公司 | By using CO-containing gas2Device and method for pretreating steel slag by tail gas air quenching |
| CN113789417A (en) * | 2021-09-28 | 2021-12-14 | 北京中航天业科技有限公司 | Atomization treatment device and treatment method for liquid steel slag |
| CN114573250A (en) * | 2022-02-24 | 2022-06-03 | 钢城集团凉山瑞海实业有限公司 | Air quenching method for preparing spherical particles from smelting slag |
| CN114657291A (en) * | 2022-03-24 | 2022-06-24 | 明正鹏达(天津)环保科技有限公司 | Device and method for quenching carbonized steel slag by using carbon dioxide |
| CN114890691A (en) * | 2022-05-09 | 2022-08-12 | 山东大学 | A kind of converter slag flue gas quenching and carbon solidification heat recovery device and method |
| CN115231316A (en) * | 2022-09-22 | 2022-10-25 | 山东大学 | Fluidized powder supply system and method based on waste gas and waste residue chilling steel slag |
| US12054795B2 (en) | 2022-09-22 | 2024-08-06 | Shandong University | System and method for delivering fluidized powder based on flue gas carrying waste slag and instant cooling steel slag |
| CN116460112A (en) * | 2023-03-09 | 2023-07-21 | 武汉钢铁有限公司 | Method and system for CO2 in steel slag mineralization flue gas |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111471817A (en) | Gas quenching method for improving stability of steel slag and recovering physical heat of molten steel slag | |
| CN107470327B (en) | Electronic waste comprehensive resource processing system and method thereof | |
| Wang et al. | Current status and development trends of innovative blast furnace ironmaking technologies aimed to environmental harmony and operation intellectualization | |
| AU2023263558B2 (en) | A processing method of a laterite-nickel ore acid leaching slag | |
| CN102363218B (en) | Method for producing copper-powder-containing iron by reducing copper-containing furnace cinders directly | |
| CN106219550B (en) | A kind of method and production system preparing industrial silicon using industrial waste SILICA FUME | |
| CN112934924A (en) | Method for recovering iron powder by direct reduction of red mud | |
| CN103627835A (en) | Method for treating nickel smelting furnace slag | |
| CN101921919B (en) | Comprehensive utilization process of molten copper slag and system thereof | |
| CN112111660A (en) | Method for enriching lithium from lithium ore and preparing ferro-silicon alloy and recycling aluminum oxide | |
| CN108912493A (en) | A method of graphene wheel hub is produced using pulverized fuel ash carbon dioxide | |
| CN102851427A (en) | Method for online production of sponge iron by using steel residue waste heat | |
| CN112934478B (en) | Method for recovering iron ore concentrate in copper slag and copper floating tailings by microwave low-temperature reduction roasting | |
| CN102268502A (en) | Spongy iron preparation method by smelting refractory iron ore (slag) with reduction rotary kiln | |
| CN214327826U (en) | Treatment and utilization device for recovering zinc oxide by smelting reduction of suspended metallurgical zinc-containing ash | |
| CN116164549B (en) | Liquid copper smelting furnace slag waste heat recovery device and treatment method thereof | |
| CN113955757B (en) | Device and process for preparing carbon dioxide capturing agent from gasified slag and combining hydrogen and alloy | |
| CN108558244B (en) | Device and preparation method for preparing cement mixture by using hot converter slag | |
| WO2015041834A2 (en) | Steel production in a coke dry quenching system | |
| CN114657291A (en) | Device and method for quenching carbonized steel slag by using carbon dioxide | |
| CN219589454U (en) | Blast furnace slag carbon residue and waste heat recovery equipment | |
| JP2001098339A (en) | Method of producing vanadium alloy iron and vanadium alloy steel | |
| CN109811094B (en) | Device and method for preprocessing steel slag by using blowing method | |
| CN112391535A (en) | Treatment and utilization device and method for recovering zinc oxide from metallurgical zinc-containing ash by suspension smelting reduction | |
| KR102272196B1 (en) | Direct reduced iron manufacturing plant based on cement manufacturing plant and manufacturing method using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200731 |