CN116555520A - Method for directly micro-alloying rare earth elements in blast furnace slag in steel - Google Patents
Method for directly micro-alloying rare earth elements in blast furnace slag in steel Download PDFInfo
- Publication number
- CN116555520A CN116555520A CN202310463524.3A CN202310463524A CN116555520A CN 116555520 A CN116555520 A CN 116555520A CN 202310463524 A CN202310463524 A CN 202310463524A CN 116555520 A CN116555520 A CN 116555520A
- Authority
- CN
- China
- Prior art keywords
- rare earth
- self
- blast furnace
- reduction
- slag
- 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 85
- 239000010959 steel Substances 0.000 title claims abstract description 85
- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 83
- 239000002893 slag Substances 0.000 title claims abstract description 75
- 238000000034 method Methods 0.000 title claims abstract description 41
- 238000005275 alloying Methods 0.000 title claims description 26
- 238000006722 reduction reaction Methods 0.000 claims abstract description 67
- 150000002910 rare earth metals Chemical class 0.000 claims abstract description 50
- 239000002994 raw material Substances 0.000 claims abstract description 43
- 229910001404 rare earth metal oxide Inorganic materials 0.000 claims abstract description 28
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 25
- 239000000463 material Substances 0.000 claims abstract description 21
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 19
- 239000000956 alloy Substances 0.000 claims abstract description 19
- 238000002156 mixing Methods 0.000 claims abstract description 19
- 239000000843 powder Substances 0.000 claims abstract description 17
- 238000009628 steelmaking Methods 0.000 claims abstract description 16
- 239000011230 binding agent Substances 0.000 claims abstract description 13
- 238000003825 pressing Methods 0.000 claims abstract description 11
- 238000000748 compression moulding Methods 0.000 claims abstract description 7
- 238000000227 grinding Methods 0.000 claims abstract description 7
- 238000003860 storage Methods 0.000 claims abstract description 4
- 239000011575 calcium Substances 0.000 claims description 20
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 19
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 18
- 229910052742 iron Inorganic materials 0.000 claims description 12
- 239000000440 bentonite Substances 0.000 claims description 11
- 229910000278 bentonite Inorganic materials 0.000 claims description 11
- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 10
- 229910052782 aluminium Inorganic materials 0.000 claims description 9
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 claims description 9
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 6
- 238000009792 diffusion process Methods 0.000 claims description 6
- 238000002844 melting Methods 0.000 claims description 6
- 230000008018 melting Effects 0.000 claims description 6
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 5
- 229910052791 calcium Inorganic materials 0.000 claims description 5
- PLDDOISOJJCEMH-UHFFFAOYSA-N neodymium(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Nd+3].[Nd+3] PLDDOISOJJCEMH-UHFFFAOYSA-N 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 3
- 229910000420 cerium oxide Inorganic materials 0.000 claims description 3
- 229910052749 magnesium Inorganic materials 0.000 claims description 3
- 239000011777 magnesium Substances 0.000 claims description 3
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 claims description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 3
- 229920003002 synthetic resin Polymers 0.000 claims description 3
- 239000000057 synthetic resin Substances 0.000 claims description 3
- 239000004375 Dextrin Substances 0.000 claims description 2
- 229920001353 Dextrin Polymers 0.000 claims description 2
- 229920002472 Starch Polymers 0.000 claims description 2
- 239000010426 asphalt Substances 0.000 claims description 2
- 229910052788 barium Inorganic materials 0.000 claims description 2
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 2
- 235000012216 bentonite Nutrition 0.000 claims description 2
- 235000019425 dextrin Nutrition 0.000 claims description 2
- 238000009472 formulation Methods 0.000 claims description 2
- MMKQUGHLEMYQSG-UHFFFAOYSA-N oxygen(2-);praseodymium(3+) Chemical compound [O-2].[O-2].[O-2].[Pr+3].[Pr+3] MMKQUGHLEMYQSG-UHFFFAOYSA-N 0.000 claims description 2
- 229910003447 praseodymium oxide Inorganic materials 0.000 claims description 2
- 239000008107 starch Substances 0.000 claims description 2
- 235000019698 starch Nutrition 0.000 claims description 2
- 235000019353 potassium silicate Nutrition 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 239000002910 solid waste Substances 0.000 abstract description 5
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 10
- 239000000292 calcium oxide Substances 0.000 description 10
- 229910004298 SiO 2 Inorganic materials 0.000 description 9
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 8
- 230000000694 effects Effects 0.000 description 8
- 238000007670 refining Methods 0.000 description 7
- 238000003723 Smelting Methods 0.000 description 6
- 239000012141 concentrate Substances 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 239000013078 crystal Substances 0.000 description 5
- 229910052746 lanthanum Inorganic materials 0.000 description 5
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 5
- 229910004261 CaF 2 Inorganic materials 0.000 description 4
- 241000723353 Chrysanthemum Species 0.000 description 4
- 235000007516 Chrysanthemum Nutrition 0.000 description 4
- 229910021193 La 2 O 3 Inorganic materials 0.000 description 4
- 239000000853 adhesive Substances 0.000 description 4
- 230000001070 adhesive effect Effects 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052684 Cerium Inorganic materials 0.000 description 3
- WNQQFQRHFNVNSP-UHFFFAOYSA-N [Ca].[Fe] Chemical compound [Ca].[Fe] WNQQFQRHFNVNSP-UHFFFAOYSA-N 0.000 description 3
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000006698 induction Effects 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 239000004115 Sodium Silicate Substances 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- -1 as in example 3 Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000004134 energy conservation Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 description 2
- 238000009616 inductively coupled plasma Methods 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000011572 manganese Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910000476 molybdenum oxide Inorganic materials 0.000 description 2
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 description 2
- 239000011863 silicon-based powder Substances 0.000 description 2
- 229910052911 sodium silicate Inorganic materials 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 229910052720 vanadium Inorganic materials 0.000 description 2
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 2
- 229910004706 CaSi2 Inorganic materials 0.000 description 1
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 1
- 229910000519 Ferrosilicon Inorganic materials 0.000 description 1
- 229910001145 Ferrotungsten Inorganic materials 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 241001062472 Stokellia anisodon Species 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- XHCLAFWTIXFWPH-UHFFFAOYSA-N [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] XHCLAFWTIXFWPH-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000009851 ferrous metallurgy Methods 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000013468 resource allocation Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 229910001935 vanadium oxide Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0006—Adding metallic additives
-
- 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
-
- 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
- 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
- C22B1/242—Binding; Briquetting ; Granulating with binders
- C22B1/243—Binding; Briquetting ; Granulating with binders inorganic
-
- 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
- C22B1/242—Binding; Briquetting ; Granulating with binders
- C22B1/244—Binding; Briquetting ; Granulating with binders organic
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
- C21C2007/0062—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires with introduction of alloying or treating agents under a compacted form different from a wire, e.g. briquette, pellet
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C2200/00—Recycling of waste material
-
- 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
Abstract
The invention provides a direct microalloying method of rare earth elements in blast furnace slag in steel, which comprises the following steps of 1) raw material crushing: grinding blast furnace slag containing rare earth elements into powder; 2) Mixing: adding a reducing agent and a binder into the crushed raw materials; 3) And (3) compression molding: pressing the mixed material into self-reduction balls or self-reduction blocks; 4) When steelmaking is carried out, the self-reduction balls or the self-reduction blocks are directly hoisted from the upper end of the steelmaking furnace or added from a storage bin; 5) Direct microalloying: the temperature of molten steel in the steelmaking process is utilized to melt the self-reduction balls or self-reduction blocks, and a reduction reaction occurs in slag phase, so that rare earth oxide in raw slag is reduced into rare earth alloy or elemental rare earth. The invention utilizes the rare earth elements in the industrial solid waste blast furnace slag to carry out direct microalloying in steelmaking, provides a brand new method for adding the rare earth elements in the production of the rare earth steel, and effectively microalloys the rare earth elements to steel materials, thereby playing a microalloying role.
Description
Technical Field
The invention relates to a direct microalloying method of rare earth elements in blast furnace slag in steel, belonging to the technical field of ferrous metallurgy.
Background
The rare earth elements can play roles in purifying molten steel, modifying impurities, refining grains and microalloying in steel materials. With the continuous progress of metallurgical technology and equipment, the purity of molten steel is continuously improved, and a better and better precondition is provided for the microalloying effect of rare earth in steel. The rare earth adding mode in the existing steel mainly comprises rare earth pure metal, mixed rare earth metal or rare earth alloy blocks, which are added during molten steel refining or made into wires by a wire feeding method in a crystallizer. However, these methods involve special smelting processes of rare earth metals or alloys, which require a certain energy consumption, are very active in chemical properties of the rare earth elements and very easy to oxidize, and when metals or alloys are added, they are very easy to oxidize and cause burning loss, so that the yield after the addition is very low, and most of them exist in the form of inclusions in steel, so that the microalloying effect is hardly exerted. This also makes the rare earth a great waste of valuable resources, restricting the application and development of rare earth in the iron and steel industry. The direct alloying method is to directly reduce the oxide in the ore or slag into simple substance state or alloy compound state during steelmaking and dissolve the oxide into molten steel to realize alloying.
The first attempt of direct alloying was the research and application of the alloy in the 20 th century, 40 th year, japan, usa, germany, etc. in electric furnaces, open furnaces and induction furnaces in succession, and direct reduction alloying was performed using tungsten ore powder instead of ferrotungsten alloy. Since the 90 s of the 20 th century, much research has been carried out in China on direct alloying. Wang Weixiang et al study V 2 O 5 Smelting vanadium-containing steel by self-reduction direct alloying, wherein the final vanadium yield reaches 95.13%; zhang Yong and the like research that the industrial molybdenum oxide is directly alloyed in a converter, and the final molybdenum yield is 92.45% -93.3%; li Jinrong and the like research on direct alloying of scheelite, and take ferrosilicon as an auxiliary reducing agent, and finally the recovery rate of tungsten reaches 98%; zhang Bo and the like research on direct alloying of the manganese ore self-reduction briquetting, and finally the yield of manganese is about 90%.
Compared with the traditional smelting mode, the direct alloying can not only utilize waste slag, low-grade ore and oxides containing alloy elements for smelting, but also reduce smelting procedures, process loss, save raw materials and improve the yield of the alloy elements, and is a promising alloying high-new technology in modern smelting. Because the rare earth oxide has very stable chemical properties and is not easy to be reduced, the current research on direct alloying is focused on oxides which are relatively easy to be reduced, such as molybdenum oxide, vanadium oxide, chromium oxide, manganese oxide and the like, and the research on the rare earth element direct alloying technology is relatively less.
As previously mentioned, only micro-scale (ppm) rare earth alloying in the steel is required to provide the advantageous effect. Meanwhile, as the blast furnace slag is used as industrial solid waste, along with continuous progress of industrial production, the required stacking place is increased continuously and environmental pollution on the surrounding is not negligible, so that the secondary utilization energy of the blast furnace slag is changed into valuables, the adverse effects of the blast furnace slag on the place requirement and the environment can be effectively relieved, and the method has important strategic value and practical significance.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for directly micro-alloying rare earth elements in blast furnace slag in steel. The rare earth elements in the industrial solid waste blast furnace slag are directly microalloyed during molten steel refining, so that a brand new method is provided for adding the rare earth elements in the production of the rare earth steel, and the rare earth elements can be effectively microalloyed to steel materials, thereby playing a microalloying role.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
a method for directly micro-alloying rare earth elements in blast furnace slag in steel comprises the following steps:
(1) Crushing raw materials: grinding blast furnace slag containing rare earth elements into powder, wherein the granularity of the ground powder is 10-100 mu m;
(2) Mixing: adding a reducing agent with the granularity of 10-100 mu m into the crushed raw materials, and uniformly mixing; adding a binder and uniformly mixing again to obtain a mixed material;
(3) And (3) compression molding: pressing the mixed material into self-reduction balls or self-reduction blocks;
(4) Feeding: when in steelmaking, the self-reducing balls or the self-reducing blocks are directly hoisted from the upper end of the steelmaking furnace or added from a storage bin, and the adding amount is 0.1-3% of the mass of molten steel;
(5) Direct microalloying: melting self-reducing balls or self-reducing blocks by utilizing the temperature of molten steel in the steelmaking process, and reducing the rare earth oxide in the raw slag into rare earth alloy or elemental rare earth by a reduction reaction in a slag phase; the microalloying time is 10 min-60 min, and the microalloying is performed in the molten steel through slag-steel interface diffusion.
The blast furnace slag containing rare earth elements is produced by blast furnace ironmaking of rare earth-iron paragenetic ore, or is added with rare earth oxide manually, or is prepared according to the self-prepared rare earth oxide of the blast furnace slag components.
The reducing agent is any one or a mixture of more of aluminum, silicon, magnesium, calcium and barium; the mass of the reducing agent is 5-20% of the total mass of the raw materials by the total amount of the raw materials.
The binder is any one or a mixture of a plurality of sodium silicate, synthetic resin, bentonite, starch, dextrin and asphalt; the mass of the binder is 0.05-1% of the total mass of the raw materials by the total amount of the raw materials.
The rare earth element exists in the form of oxide, which is any one or the mixture of a plurality of lanthanum oxide, cerium oxide, praseodymium oxide and neodymium oxide; based on the total weight of the raw materials, the total weight of the rare earth oxide is 0.3-10% of the total weight of the raw materials.
The diameter of the self-reduction ball is 10 mm-60 mm; the size of the self-reduction block is 10 mm-60 mm.
The invention has the beneficial effects that:
the invention adopts the blast furnace slag containing rare earth oxide as raw material, the blast furnace slag is directly and evenly mixed with the reducing agent and pressed into self-reducing balls (blocks), then the self-reducing balls (blocks) are directly added into molten steel, the reducing agent in the self-reducing balls (blocks) can reduce the rare earth oxide in the blast furnace slag into an alloy or simple substance state which can be dissolved in the molten steel, and finally the slag-steel interface is diffused and microalloyed into the molten steel to play a microalloying role.
The rare earth element source of the invention is blast furnace slag containing rare earth, which belongs to industrial solid waste, the invention can recycle the industrial solid waste with high efficiency, alleviate adverse effect of continuous stockpiling of the blast furnace slag on field requirement and environment, and no extra energy consumption is added in the steelmaking adding process, and the rare earth element in the blast furnace slag can be effectively alloyed directly to steel materials to exert micro-alloying effect, thereby changing waste into valuables.
In order to fully contact the blast furnace slag and the reducing agent and improve the dynamic conditions of the reduction reaction, the invention ensures that the reaction is more complete, uniformly mixes the blast furnace slag and the reducing agent and presses the blast furnace slag and the reducing agent into self-reducing balls (blocks), and a small amount of binding agent (sodium silicate, synthetic resin, bentonite and the like) is added in the pressing process, so that the self-reducing balls (blocks) have certain toughness to ensure that the self-reducing balls (blocks) cannot be broken during storage and transportation, and ensure that elements contained in the binding agent do not influence the reduction reaction in the self-reducing balls (blocks).
The invention effectively utilizes the reduction reaction to directly microalloy rare earth elements from blast furnace slag into steel materials in the production of the steel materials, reduces the rare earth oxides in the self-reduction balls (blocks) into the molten steel by utilizing the heat of the molten steel, does not need to additionally increase energy consumption or specially smelt rare earth metals or rare earth alloys, provides a brand new way for adding rare earth in the production of the steel materials, and has the characteristics of energy conservation and environmental protection.
The invention has the advantages of cheap and easily obtained raw materials, stable and not severe physical and chemical process, safe production process, simple material source, easy industrial production, energy conservation, environmental protection and reasonable resource allocation and utilization.
Drawings
FIG. 1 is a schematic illustration of the process flow of the method of the present invention.
FIG. 2 is a spectral surface scan of the enrichment region of each element in the aluminum-containing self-reduced mass after thermal reduction.
Wherein, (a) reduced product morphology; (b) an oxygen element; (c) magnesium element: (d) fluorine element; (e) a calcium element; (f) an aluminum element; (g) elemental silicon; (h) rare earth lanthanum element. The region 2 product in (a) is Si; the product of zone 3 is CaSi 2 The method comprises the steps of carrying out a first treatment on the surface of the Zone(s)The domain 4 product was (Ca 0.2 La 0.8 )Si 2 。
FIG. 3 shows the diffraction pattern of the chrysanthemum pool in each region of the aluminum-containing self-reduced block after thermal reduction reaction and the analysis result.
Detailed Description
The following describes the embodiments of the present invention in further detail with reference to examples.
The baiyuneboite is a symbiotic deposit rich in rare earth resources, a certain amount of rare earth elements and iron concentrate coexist in the iron concentrate after mineral separation, and the iron concentrate enters a subsequent blast furnace ironmaking process, and the rare earth elements are enriched in blast furnace slag after the process. In addition, a certain amount of rare earth oxide can be added into the blast furnace slag to increase the rare earth content in the slag, or the blast furnace slag containing rare earth can be manually prepared according to the component characteristics of the blast furnace slag.
The invention adopts blast furnace slag containing rare earth oxide as raw material, in order to make the blast furnace slag fully contact with reducing agent to raise the dynamics condition of reduction reaction, make the reaction more fully and not significantly reduce the temperature of molten steel (when self-reducing ball (block) is added, the molten steel is cooled due to heat absorption effect, but the temperature control during refining of molten steel is important, the fluctuation of temperature control can not be too large, the volume and addition quantity of the produced self-reducing ball (block) are moderate, the molten steel temperature can be reduced to less than 10 deg.C), the blast furnace slag and reducing agent are uniformly mixed and pressed into self-reducing ball (block) with moderate volume, then the self-reducing ball (block) is added into molten steel, the reducing agent in the self-reducing ball (block) can reduce rare earth oxide in the blast furnace slag into alloy or simple substance state dissolved in molten steel, as in example 3, lanthanum oxide is reduced into (Ca) 0.2 La 0.8 )Si 2 As shown in fig. 2 and 3, after a certain period of time, the slag-steel interface diffuses and microalloys into the molten steel to exert a microalloying effect.
Example 1
A method for directly micro-alloying rare earth elements in blast furnace slag in steel comprises the following specific steps:
(1) The raw material sources are as follows: the Bayan obo rare earth-iron intergrowth ore is adopted as main feed of iron concentrate, the rare earth-containing blast furnace slag generated after blast furnace ironmaking is adopted as raw material, and the blast furnace slag components are shown in table 1;
TABLE 1 blast furnace slag component (wt%)
| CaO | SiO 2 | Al 2 O 3 | MgO | CaF 2 | La 2 O 3 | CeO 2 |
| 38.29 | 38.28 | 13.61 | 8.72 | 0.55 | 0.14 | 0.41 |
(2) Mixing: mechanically grinding the raw materials into powder, wherein the granularity of the ground powder is 60-80 mu m; adding reducer aluminum powder with granularity of 50-70 mu m, and uniformly mixing by adopting a mechanical stirring or roller mixer; adding the adhesive bentonite, and uniformly mixing again to obtain a mixed material;
the mass of the added reducing agent aluminum powder is 10% of the total mass of the raw materials by the total amount of the raw materials; the mass of the binder bentonite is 0.06% of the total mass of the raw materials;
(3) And (3) compression molding: pressing the mixed material into self-reduction balls with the diameter of 30mm by using a ball pressing machine;
(4) Adding the self-reduction balls: when a ladle refining furnace (LF) is in place, the self-reduction ball is filled into a woven bag, and is directly hoisted and added from the upper end of the ladle steel furnace, wherein the adding amount is 1.5% of the mass of molten steel;
(5) Direct microalloying: melting the self-reduction ball by utilizing the temperature (1570-1580 ℃) of molten steel in the steelmaking process, and carrying out reduction reaction in a slag phase to reduce rare earth oxide in raw slag into rare earth alloy which can be dissolved in molten steel, wherein the reduction reaction process is shown in formulas (1) and (2); the microalloying time is 25min, and the microalloying is performed in the molten steel through slag-steel interface diffusion.
The first step: (SiO) 2 )+Al→Si+Al 2 O 3 (1)
And a second step of: si+ (REO) + (CaO) - (Ca) 0.2 RE 0.8 )Si 2 +SiO 2 (2)
The method is used for directly alloying to obtain the steel billet, and finally, an inductively coupled plasma mass spectrometer (ICP-MS) is used for measuring the rare earth lanthanum content in the steel billet to be 3.6ppm and the rare earth cerium content to be 11.8ppm.
Example 2
A method for directly micro-alloying rare earth elements in blast furnace slag in steel comprises the following specific steps:
(1) The raw material sources are as follows: the Bayan obo rare earth-iron intergrowth ore is adopted as the main feed of iron concentrate, the blast furnace slag containing rare earth produced after blast furnace ironmaking is mixed with 0.4% (wt) lanthanum oxide and 1% (wt) cerium oxide as raw materials, and the blast furnace slag components after rare earth oxide is mixed are shown in table 2;
TABLE 2 blast furnace slag component (wt.%) after adding rare earth oxide
| CaO | SiO 2 | Al 2 O 3 | MgO | CaF 2 | La 2 O 3 | CeO 2 |
| 37.75 | 37.74 | 13.42 | 8.60 | 0.54 | 0.54 | 1.41 |
(2) Mixing: mechanically grinding the raw materials into powder, wherein the granularity of the ground powder is 60-80 mu m; adding reducer aluminum powder and silicon powder with granularity of 50-70 mu m, and uniformly mixing; adding the adhesive bentonite, and uniformly mixing again to obtain a mixed material;
the mass of the added reducing agent aluminum powder and silicon powder is respectively 10 percent and 2 percent of the total mass of the raw materials by the total amount of the raw materials; the mass of the binder bentonite is 0.09% of the total mass of the raw materials;
(3) And (3) compression molding: pressing the mixed material into self-reduction balls with the diameter of 30mm by using a ball pressing machine;
(4) And (3) adding a reducing ball: when LF refining is in place, the self-reduction balls are filled into woven bags, and are directly hoisted and added from the upper end of a ladle steel furnace, wherein the addition amount is 1.5% of the mass of molten steel;
(5) Direct microalloying: melting the self-reduction ball by utilizing the temperature (1570-1580 ℃) of molten steel in the steelmaking process, and carrying out reduction reaction in a slag phase to reduce rare earth oxide in raw slag into rare earth alloy which can be dissolved in molten steel, wherein the reduction reaction process is shown in formulas (3) and (4); the microalloying time is 25min, and the microalloying is performed in the molten steel through slag-steel interface diffusion.
The first step: (SiO) 2 )+Al→Si+Al 2 O 3 (3)
And a second step of: si+ (REO) + (CaO) - (Ca) 0.2 RE 0.8 )Si 2 +SiO 2 (4)
The method is used for directly alloying to obtain the steel billet, and the content of rare earth lanthanum in the steel billet is measured to be 10.2ppm by ICP-MS, and the content of rare earth cerium is measured to be 29.6ppm.
Example 3
A method for directly micro-alloying rare earth elements in blast furnace slag in steel comprises the following specific steps:
(1) The raw material sources are as follows: simulating blast furnace slag components by using analytically pure oxides to prepare slag, wherein the prepared slag components are shown in table 3;
TABLE 3 formulation slag composition (wt%)
| CaO | SiO 2 | Al 2 O 3 | MgO | CaF 2 | La 2 O 3 |
| 38.39 | 38.27 | 13.54 | 8.67 | 0.55 | 0.58 |
(2) Mixing: mechanically grinding the raw materials into powder, wherein the granularity of the ground powder is 60-80 mu m; adding reducer aluminum powder with granularity of 50-70 mu m, and uniformly mixing; adding the adhesive bentonite, and uniformly mixing again to obtain a mixed material;
wherein the mass of the added reducing agent aluminum powder is 13% of the total mass of the raw materials; the mass of the binder bentonite is 0.07% of the total mass of the raw materials;
(3) And (3) compression molding: the mixed materials are pressed into self-reduction blocks (cylinders) by a ball pressing machine, wherein the diameter of the bottom surface of each cylinder is 15mm, and the height of each cylinder is 20mm;
(4) Feeding: after the intermediate frequency induction furnace melts the molten steel, adding the self-reduction block into the molten steel from a hopper in an induction furnace chamber through an inclined hopper, wherein the adding amount is 2% of the mass of the molten steel;
(5) Direct microalloying: melting the self-reduction ball by utilizing the temperature (1580-1600 ℃) of molten steel in the steelmaking process, and carrying out reduction reaction in a slag phase to reduce rare earth lanthanum oxide in raw slag into rare earth alloy which can be dissolved in molten steel, wherein the reduction reaction process is shown in formulas (5) and (6); the microalloying time is 20min, and the microalloying is performed in the molten steel through slag-steel interface diffusion.
The first step: (SiO) 2 )+Al→Si+Al 2 O 3 (5)
And a second step of: si+ (La) 2 O 3 )+(CaO)→(Ca 0.2 La 0.8 )Si 2 +SiO 2 (6)
The method directly alloys to obtain the billet, and the content of rare earth lanthanum in the billet is measured to be 13.6ppm by ICP-MS.
The spectrum surface scanning of the distribution of the reduction products and the nearby elements in the aluminum-containing self-reduction block after the thermal reduction reaction in the embodiment is shown in fig. 2, and it can be seen that a region 2 enriched in Si element exists in the low oxygen region after deoxidization by the reduction reaction; a region 3 enriched in Ca element and Si element; and a region 4 of a nearby Ca element, rare earth La element, and Si element.
The crystal structure of the reduced product in the low oxygen region is calibrated by Electron Back Scattering Diffraction (EBSD) of the chrysanthemum Chi Yanshe pattern, the chrysanthemum pool diffraction pattern of the reduced product after the reduction reaction in the aluminum-containing self-reduction block after the thermal reduction reaction and the crystal structure calibrated according to the chrysanthemum Chi Yanshe pattern are shown in FIG. 3, and it can be seen that the unit cell parameters of the region 2 in FIG. 2 are α=β=90°, γ=120°, which is the crystal structure of Si, combined with the result of the enrichment of the Si element by region 2 in fig. 2, the reduction product in this region is Si; similarly, the unit cell parameters of region 3 in FIG. 2 areα=β=90°, γ=120°, ca 2 The crystal structure of Si, combined with the result that region 3 in FIG. 2 is enriched with Ca element and Si element, the reduction product in this region is Ca 2 Si; the unit cell parameters for region 4 in FIG. 2 areα=β=γ=90°, which is (Ca 0.2 RE 0.8 )Si 2 In combination with the result of the enrichment of zone 4 in FIG. 2 with Ca, rare earth La, anger and Si, the reduction product in this zone is (Ca 0.2 La 0.8 )Si 2 。
Because the reduction reaction of the present invention is essentially a deoxidization process, the low oxygen region in fig. 2 is a reduction product, and the result shown in fig. 2 and 3 is combined to obtain the elemental composition and crystal structure of the reduction product, thereby obtaining the type of the reduction product, i.e., the substance generated after reduction.
Example 4
A method for directly micro-alloying rare earth elements in blast furnace slag in steel comprises the following specific steps:
(1) The raw material sources are as follows: the Bayan obo rare earth-iron intergrowth ore is adopted as the main feed of iron concentrate, the rare earth-containing blast furnace slag generated after blast furnace ironmaking is adopted as the raw material, and the blast furnace slag components are shown in table 4;
TABLE 4 blast furnace slag component (wt%)
| CaO | SiO 2 | Al 2 O 3 | MgO | CaF 2 | La 2 O 3 | CeO 2 |
| 41.36 | 35.68 | 12.64 | 8.83 | 0.52 | 0.34 | 0.63 |
(2) Mixing: mechanically grinding the raw materials into powder, wherein the granularity of the ground powder is 20-40 mu m; adding reducing agent aluminum powder with the granularity of 20-40 mu m and reducing agent calcium iron powder with the granularity of 90-100 mu m (wherein the mass fraction of calcium in the calcium iron powder is 25 percent), and uniformly mixing; adding the adhesive bentonite, and uniformly mixing again to obtain a mixed material;
the mass of the added reducing agent aluminum powder and the mass of the added calcium iron powder are respectively 7% and 3% of the total mass of the raw materials; the mass of the binder bentonite is 0.05% of the total mass of the raw materials;
(3) And (3) compression molding: pressing the mixed material into self-reduction balls with the diameter of 30mm by using a ball pressing machine;
(4) Adding the self-reduction balls: when a ladle refining furnace (LF) is in place, the self-reduction ball is filled into a woven bag, and is directly hoisted and added from the upper end of the ladle steel furnace, wherein the adding amount is 1.5% of the mass of molten steel;
(5) Direct microalloying: melting the self-reduction ball by utilizing the temperature (1570-1580 ℃) of molten steel in the steelmaking process, and carrying out reduction reaction in a slag phase to reduce rare earth oxide in raw slag into elemental rare earth metal and rare earth alloy which can be dissolved in molten steel, wherein calcium can directly reduce Rare Earth Oxide (REO) into elemental rare earth metal (RE); the aluminum reduction process is divided into two steps, the first step is that aluminum firstly reduces silicon dioxide (SiO 2 ) Reduction to elemental silicon, the second step being the reduction of the rare earth oxides and calcium oxide in the slag to (Ca 0.2 RE 0.8 )Si 2 The reduction reaction processes are respectively shown in formulas (7), (8) and (9); the microalloying time is 25min, and the microalloying is performed in the molten steel through slag-steel interface diffusion.
Calcium reduction:
(REO) +Ca→RE+CaO (formula 7)
Aluminum reduction:
the first step: (SiO) 2 )+Al→Si+Al 2 O 3 (8)
And a second step of: si+ (REO)+(CaO)→(Ca 0.2 RE 0.8 )Si 2 +SiO 2 (9)
The method is used for directly alloying to obtain a steel billet, and an inductively coupled plasma mass spectrometer (ICP-MS) is used for measuring the rare earth lanthanum content in the steel billet to be 7.6ppm and the rare earth cerium content to be 14.8ppm.
It should be noted that: the above examples are only for the purpose of clearly illustrating the specific embodiments of the present invention, and are not limited to the embodiments. Other variations in various forms will be apparent to those of ordinary skill in the art in view of the foregoing description. It is not necessary for all embodiments to be exhaustive. And all such variations and modifications are intended to be included herein within the scope of the present invention.
Claims (6)
1. A method for directly micro-alloying rare earth elements in blast furnace slag in steel is characterized by comprising the following steps:
(1) Crushing raw materials: grinding blast furnace slag containing rare earth elements into powder, wherein the granularity of the ground powder is 10-100 mu m;
(2) Mixing: adding a reducing agent with the granularity of 10-100 mu m into the crushed raw materials, and uniformly mixing; adding a binder and uniformly mixing again to obtain a mixed material;
(3) And (3) compression molding: pressing the mixed material into self-reduction balls or self-reduction blocks;
(4) Feeding: when in steelmaking, the self-reducing balls or the self-reducing blocks are directly hoisted from the upper end of the steelmaking furnace or added from a storage bin, and the adding amount is 0.1-3% of the mass of molten steel;
(5) Direct microalloying: melting self-reducing balls or self-reducing blocks by utilizing the temperature of molten steel in the steelmaking process, and reducing the rare earth oxide in the raw slag into rare earth alloy or elemental rare earth by a reduction reaction in a slag phase; the microalloying time is 10 min-60 min, and the microalloying is performed in the molten steel through slag-steel interface diffusion.
2. The method according to claim 1, wherein the rare earth element-containing blast furnace slag is a blast furnace slag produced by blast furnace ironmaking of a rare earth-iron paragenetic ore, or a blast furnace slag to which a rare earth oxide is artificially added, or a rare earth oxide-containing formulation slag self-formulated according to a blast furnace slag component.
3. The method of claim 1, wherein the reducing agent is any one or a mixture of aluminum, silicon, magnesium, calcium, and barium; the mass of the reducing agent is 5-20% of the total mass of the raw materials by the total amount of the raw materials.
4. The method of claim 1, wherein the binder is any one or a mixture of water glass, synthetic resin, bentonite, starch, dextrin and asphalt; the mass of the binder is 0.05-1% of the total mass of the raw materials by the total amount of the raw materials.
5. The method of claim 1, wherein the rare earth element is present in the form of an oxide, which is any one or a mixture of a plurality of lanthanum oxide, cerium oxide, praseodymium oxide, neodymium oxide; based on the total weight of the raw materials, the total weight of the rare earth oxide is 0.3-10% of the total weight of the raw materials.
6. The method of claim 1, wherein the diameter of the self-reducing spheres is from 10mm to 60mm; the size of the self-reduction block is 10 mm-60 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310463524.3A CN116555520A (en) | 2023-04-26 | 2023-04-26 | Method for directly micro-alloying rare earth elements in blast furnace slag in steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310463524.3A CN116555520A (en) | 2023-04-26 | 2023-04-26 | Method for directly micro-alloying rare earth elements in blast furnace slag in steel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116555520A true CN116555520A (en) | 2023-08-08 |
Family
ID=87489106
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310463524.3A Pending CN116555520A (en) | 2023-04-26 | 2023-04-26 | Method for directly micro-alloying rare earth elements in blast furnace slag in steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116555520A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117660726A (en) * | 2024-02-02 | 2024-03-08 | 东北大学 | Steel rare earth treatment method for high-strength engineering machinery |
| CN117660726B (en) * | 2024-02-02 | 2024-04-26 | 东北大学 | Steel rare earth treatment method for high-strength engineering machinery |
-
2023
- 2023-04-26 CN CN202310463524.3A patent/CN116555520A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117660726A (en) * | 2024-02-02 | 2024-03-08 | 东北大学 | Steel rare earth treatment method for high-strength engineering machinery |
| CN117660726B (en) * | 2024-02-02 | 2024-04-26 | 东北大学 | Steel rare earth treatment method for high-strength engineering machinery |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103898413B (en) | V n micro alloying frotton steel and preparation method thereof | |
| CN108085578A (en) | A kind of automobile gear special steel and its production technology | |
| KR101598449B1 (en) | Process for producing low-cost clean steel | |
| CN106834602A (en) | Steel-making rare-earth aluminum-calcium ferrosilicon composite alloy and preparation method thereof | |
| KR20150106661A (en) | Manufacturing method of Fe-Si from Fe-Ni slag | |
| CN102827997A (en) | Calcium carbide ferro-aluminium alloy used for smelting steel, and preparation method thereof | |
| US20200024145A1 (en) | Method for resource recovery from silicon slag and deoxidizing agent for iron and steelmaking | |
| CN102212736B (en) | Method for preparing niobium microalloy steel by using low-niobium molten iron | |
| CN101413044B (en) | Alloy addition method for improving yield of ferromolybdenum | |
| CN105886765A (en) | Method for producing ferrosilicon | |
| CN102586537A (en) | Vanadium extraction coolant and its preparation method | |
| CN115404339B (en) | Method for developing and utilizing oolitic high-phosphorus iron ore | |
| CN116555520A (en) | Method for directly micro-alloying rare earth elements in blast furnace slag in steel | |
| CN105568178A (en) | New manufacturing process of hot-rolled bar for carburized and quenched gear shaft of automobile transmission | |
| Hu et al. | Direct chromium alloying by chromite ore with the presence of metallic iron | |
| CN108715972A (en) | A kind of low-phosphorous silicon iron product and its smelting process | |
| CN101491780B (en) | Desulphurizing slag powder treatment method and desulphurizing slag reutilization method | |
| Zhao et al. | Interface Behavior and Interaction Mechanism between Vanadium-Titanium Magnetite Carbon Composite Briquette and Sinter in Softening-Melting-Dripping Process | |
| CN105624365B (en) | A kind of alkaline earth oxide is combined molten steel refining agent and preparation method thereof | |
| CN212293627U (en) | Online quenching and tempering device for slag tapping cooling process of molten steel slag | |
| CN105274281A (en) | Method used for controlling boron content in steel accurately | |
| CN105463141B (en) | A kind of method using the low poor nickelic molten iron of grade smelting laterite-nickel ores | |
| CN103031409A (en) | Novel process of steelmaking deoxidization by utilizing precipitator dust of refining furnace | |
| KR101182997B1 (en) | Deoxidation method of pouring molten metal by electric arc furnace | |
| CN101565792A (en) | Method for smelting boron steel |
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 |