CN103509934B - Method for producing austenitic stainless steel by using nickel and chromium ores - Google Patents
Method for producing austenitic stainless steel by using nickel and chromium ores Download PDFInfo
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- CN103509934B CN103509934B CN201210336287.6A CN201210336287A CN103509934B CN 103509934 B CN103509934 B CN 103509934B CN 201210336287 A CN201210336287 A CN 201210336287A CN 103509934 B CN103509934 B CN 103509934B
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- nickel
- stainless steel
- ore
- chrome ore
- chromium
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- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 title claims abstract description 392
- 229910052759 nickel Inorganic materials 0.000 title claims abstract description 195
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 title claims abstract description 134
- 239000011651 chromium Substances 0.000 title claims abstract description 69
- 229910052804 chromium Inorganic materials 0.000 title claims abstract description 63
- 238000004519 manufacturing process Methods 0.000 title abstract description 7
- 229910000963 austenitic stainless steel Inorganic materials 0.000 title abstract 2
- 229910001220 stainless steel Inorganic materials 0.000 claims abstract description 69
- 239000010935 stainless steel Substances 0.000 claims abstract description 69
- 238000005245 sintering Methods 0.000 claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 31
- 238000002156 mixing Methods 0.000 claims abstract description 19
- 239000013078 crystal Substances 0.000 claims abstract description 9
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 74
- 239000011707 mineral Substances 0.000 claims description 74
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 72
- 238000000034 method Methods 0.000 claims description 59
- 239000012943 hotmelt Substances 0.000 claims description 42
- 229910052742 iron Inorganic materials 0.000 claims description 36
- 229910001566 austenite Inorganic materials 0.000 claims description 29
- 229910017052 cobalt Inorganic materials 0.000 claims description 22
- 239000010941 cobalt Substances 0.000 claims description 22
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 22
- 238000002844 melting Methods 0.000 claims description 21
- 230000008018 melting Effects 0.000 claims description 21
- 239000002893 slag Substances 0.000 claims description 21
- 229910052751 metal Inorganic materials 0.000 claims description 15
- 239000002184 metal Substances 0.000 claims description 15
- 229910000831 Steel Inorganic materials 0.000 claims description 13
- 238000013467 fragmentation Methods 0.000 claims description 13
- 238000006062 fragmentation reaction Methods 0.000 claims description 13
- 239000010959 steel Substances 0.000 claims description 13
- 239000012530 fluid Substances 0.000 claims description 10
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 9
- 235000011149 sulphuric acid Nutrition 0.000 claims description 9
- 239000001117 sulphuric acid Substances 0.000 claims description 9
- 230000002829 reductive effect Effects 0.000 claims description 8
- 238000010079 rubber tapping Methods 0.000 claims description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 7
- 238000005453 pelletization Methods 0.000 claims description 7
- 239000000571 coke Substances 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 241001417490 Sillaginidae Species 0.000 claims description 3
- 238000003723 Smelting Methods 0.000 abstract description 9
- 239000007788 liquid Substances 0.000 abstract description 7
- 241001062472 Stokellia anisodon Species 0.000 abstract description 6
- 238000009749 continuous casting Methods 0.000 abstract description 4
- UGKDIUIOSMUOAW-UHFFFAOYSA-N iron nickel Chemical compound [Fe].[Ni] UGKDIUIOSMUOAW-UHFFFAOYSA-N 0.000 abstract 4
- 229910000604 Ferrochrome Inorganic materials 0.000 abstract 3
- 238000010438 heat treatment Methods 0.000 abstract 1
- 238000012216 screening Methods 0.000 abstract 1
- 239000000203 mixture Substances 0.000 description 19
- 239000000126 substance Substances 0.000 description 11
- 229910052799 carbon Inorganic materials 0.000 description 9
- 229910000975 Carbon steel Inorganic materials 0.000 description 6
- 239000010962 carbon steel Substances 0.000 description 6
- 238000009628 steelmaking Methods 0.000 description 5
- 238000011084 recovery Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000003245 coal Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 150000002815 nickel Chemical class 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical group [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 239000012452 mother liquor Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/004—Making spongy iron or liquid steel, by direct processes in a continuous way by reduction from ores
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/006—Starting from ores containing non ferrous metallic oxides
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/02—Making spongy iron or liquid steel, by direct processes in shaft furnaces
- C21B13/023—Making spongy iron or liquid steel, by direct processes in shaft furnaces wherein iron or steel is obtained in a molten state
- C21B13/026—Making spongy iron or liquid steel, by direct processes in shaft furnaces wherein iron or steel is obtained in a molten state heated electrically
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/08—Making spongy iron or liquid steel, by direct processes in rotary furnaces
-
- 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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/005—Manufacture of stainless steel
-
- 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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
-
- 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
- C22B23/00—Obtaining nickel or cobalt
- C22B23/005—Preliminary treatment of ores, e.g. by roasting or by the Krupp-Renn process
-
- 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
- C22B23/00—Obtaining nickel or cobalt
- C22B23/02—Obtaining nickel or cobalt by dry processes
- C22B23/023—Obtaining nickel or cobalt by dry processes with formation of ferro-nickel or ferro-cobalt
-
- 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
- C22B34/00—Obtaining refractory metals
- C22B34/30—Obtaining chromium, molybdenum or tungsten
- C22B34/32—Obtaining chromium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
A method for producing austenitic stainless steel by using nickel and chromium ores comprises the steps of (a) crushing, screening and mixing nickel ores, then sending the nickel ores to a rotary kiln for roasting to remove free water and crystal water in the nickel ores, carrying out pre-reduction, and smelting by a submerged arc furnace to obtain rough molten nickel iron; (b) sintering the chromium ore into reduction sintering chromium ore by a heating furnace, and smelting by an ore furnace to obtain ferrochrome water; (c) putting the rough molten nickel iron and the ferrochrome water into a converter in a hot conveying mode, and smelting into stainless steel liquid; (d) and (3) manufacturing the stainless steel liquid into a billet by a continuous casting machine. The invention utilizes the rotary kiln to roast and then prepares the rough molten nickel iron through the submerged arc furnace, and simultaneously, the rough molten nickel iron is directly put into the converter in a hot feeding way together with the ferrochrome water to smelt into the stainless steel liquid, thereby reducing the smelting cost.
Description
Technical field
The present invention relates to a kind of method of steel-making, particularly relate to a kind of method utilizing nickel, chrome ore to produce austenite stainless steel.
Background technology
In the steel-making processing procedure of traditional austenite stainless steel, with steel scrap and alloy iron for main raw material, become after molten iron through electrosmelting, drop into converter smelting again, and depending on produced steel grade (be as 200 or 300 be stainless steel), add nickel, Chrome metal powder to scale in converter, finally obtained austenite stainless steel.Nickelalloy belongs to high precious metal, accounts for stainless cost up to 40% to 50%, if therefore the fluctuation of nickel valency is large, the as easy as rolling off a log profit affecting stainless steel plant, even has the possibility causing loss.
Therefore have and propose directly with nickel ores, chrome ore is that raw material drops into mineral hot furnace or blast furnace, the direct processing procedure smelting mother liquor of stainless steel, as No. CN102212691Ath, Chinese patent or No. CN101701312A, to save stainless production cost, but not through pre-treatment in the ore of above-mentioned processing procedure, there are a large amount of free water or crystal water, cause the process of melting need increase power consumption to remove moisture, and there is Gold in Ores, to belong to the component proportions of nickel wayward, the shortcomings such as impurity too much and the rate of recovery is not good, in addition often to have nickel minerals in cobalt ore is entrained in, if in the mode directly dropping into ore, rare metal will be made also to exist in molten steel with smelting cannot extraction and recovery, so still not mature enough in the production application of reality, perfect.
Summary of the invention
A kind of utilize nickel, chrome ore improving process stability is the object of the present invention is to provide to produce the method for austenite stainless steel.
The present invention utilizes nickel, chrome ore to produce the method for austenite stainless steel, comprises following steps:
A nickel minerals is carried out fragmentation, sieves by (), deliver to a rotary kiln baking after batch mixing to remove free water in nickel minerals and crystal water, coordinating reductive agent together to drop in roasting process to carry out prereduction becomes nickel slag, and the nickel slag after roasting obtains raw nickel matte molten iron by a mineral hot furnace melting again.
B () sinters chrome ore into reduction sintering chrome ore through a process furnace, reduction sintering chrome ore and coke grain are sent into a mineral hot furnace melting again and obtained chromium hot melt.
C the mode that described raw nickel matte molten iron, chromium hot melt send with heat is dropped into converter by (), smelt into molten stainless steel.
D molten stainless steel is made steel billet with continuous caster by ().
The object of the invention to solve the technical problems also can be applied to the following technical measures to achieve further.
Preferably, the aforesaid method utilizing nickel, chrome ore to produce austenite stainless steel, wherein in step (a), the maturing temperature of this rotary kiln is 800 DEG C to 950 DEG C, and in mineral hot furnace the tapping temperature of this raw nickel matte molten iron about 1400 DEG C to 1500 DEG C, in addition, in step (b), chrome ore also mixes with coke powder by this chrome ore before sintering, pelletizing is made through ball press, and remove moisture with dryer, just send into process furnace sintering, and the granularity of the reduction sintering chrome ore of feeding mineral hot furnace is for being less than 30mm.
Preferably, the method for austenite stainless steel produced by aforesaid nickel, the chrome ore of utilizing, and wherein in step (a), nickel minerals carries out fragmentation, sieves, be first send a dry kiln to before batch mixing, to remove the free water in nickel minerals.
Moreover another object of the present invention, is to provide a kind of utilize nickel, chrome ore improveing rare metal recovery rate to produce the method for austenite stainless steel.
The present invention utilizes nickel, chrome ore to produce the method for austenite stainless steel, comprises following steps:
A nickel minerals is carried out fragmentation, adds water and size mixing by (), and after being uniformly mixed under hyperbaric environment with sulphuric acid soln, filtering out the mineral finished fluid containing nickel, cobalt, this be nickeliferous, the mineral finished fluid of cobalt electrolytically draws electrolytic nickel and cobalt metal again.
B () sinters chrome ore into reduction sintering chrome ore through a process furnace, reduction sintering chrome ore obtains chromium hot melt through a mineral hot furnace melting again.
(c) by described electrolytic nickel with Belt Conveying to converter feed bin, and coordinate the mode that chromium hot melt send with heat, drop into converter, smelt into molten stainless steel.
D molten stainless steel is made steel billet with continuous caster by ().
The object of the invention to solve the technical problems also can be applied to the following technical measures to achieve further.
Preferably, the aforesaid method utilizing nickel, chrome ore to produce austenite stainless steel, wherein in step (a), the solid-to-liquid ratio that this nickel minerals mixes with sulphuric acid soln is 1:4, and in the environment of pressure 4 to 5MPa, temperature 250 DEG C to 300 DEG C mix and blend, in addition, in step (b), chrome ore also mixes with coke powder by this chrome ore before sintering, pelletizing is made through ball press, and remove moisture with dryer, just send into process furnace sintering, and the granularity of the reduction sintering chrome ore of feeding mineral hot furnace is for being less than 30mm.
Moreover another object of the present invention, is to provide a kind of utilize nickel, chrome ore improving nickel minerals rate of utilization to produce the method for austenite stainless steel.
The present invention utilizes nickel minerals to produce the method for austenite stainless steel, comprises following steps:
A nickel raw ore material is distinguished into a low grade nickel ore through ore dressing by (), and a higher-grade nickel minerals, and the nickel content wherein in low grade nickel ore is less than 1.5wt%, and the nickel content in higher-grade nickel minerals is not less than 1.5wt%.
B low grade nickel ore is carried out fragmentation, adds water and size mixing by (), and after mixing with sulphuric acid soln and the mineral finished fluid filtered out containing nickel, cobalt, this is nickeliferous, the mineral finished fluid of cobalt electrolytically draws electrolytic nickel and cobalt metal again.
C higher-grade nickel minerals is carried out fragmentation, sieves by (), deliver to a rotary kiln baking after batch mixing to remove free water in higher-grade nickel minerals and crystal water, coordinating reductive agent together to drop in roasting process to carry out prereduction becomes nickel slag, and the nickel slag after roasting obtains raw nickel matte molten iron by a mineral hot furnace melting again.
D () sinters chrome ore into reduction sintering chrome ore through a process furnace, reduction sintering chrome ore and coke grain are sent into a mineral hot furnace melting again and obtained chromium hot melt.
(e) by described electrolytic nickel with Belt Conveying to converter batch bin, and coordinate the mode that raw nickel matte molten iron, chromium hot melt send with heat, drop into converter, smelt into molten stainless steel.
F molten stainless steel is made steel billet with continuous caster by ().
The object of the invention to solve the technical problems also can be applied to the following technical measures to achieve further.
Preferably, the aforesaid method utilizing nickel, chrome ore to produce austenite stainless steel, wherein in step (b), the solid-to-liquid ratio that this low grade nickel ore mixes with sulphuric acid soln is 1:4, and in the environment of pressure 4-5MPa, temperature 250 DEG C to 300 DEG C mix and blend.
Preferably, the aforesaid method utilizing nickel, chrome ore to produce austenite stainless steel, wherein in step (c), the maturing temperature of this rotary kiln is 800 DEG C to 950 DEG C, and in mineral hot furnace the tapping temperature of this raw nickel matte molten iron about 1400 DEG C to 1500 DEG C, in addition, in step (d), chrome ore also mixes with coke powder by this chrome ore before sintering, pelletizing is made through ball press, and remove moisture with dryer, just send into process furnace sintering, and the granularity of the reduction sintering chrome ore of feeding mineral hot furnace is for being less than 30mm.
Preferably, the method for austenite stainless steel produced by aforesaid nickel, the chrome ore of utilizing, and wherein in step (c), higher-grade nickel minerals carries out fragmentation, sieves, be first send a dry kiln to before batch mixing, to remove the free water in higher-grade nickel minerals.
Beneficial effect of the present invention is: utilize rotary kiln baking prereduction to obtain raw nickel matte molten iron through mineral hot furnace melting again and drop into converter again, and utilize high pressure acidleach again electrolysis obtain the mode of metallic nickel, the electrolytic nickel obtaining purity higher drops into converter again, the mode simultaneously coordinating chromium hot melt to send with heat directly drops into converter, smelt into molten stainless steel, in the control of alloying constituent easily, also effectively smelting cost can be reduced.
Accompanying drawing explanation
Fig. 1 is a schema, illustrates that the present invention utilizes nickel, chrome ore to produce the first preferred embodiment of the method for austenite stainless steel;
Fig. 2 is a schema, illustrates that the present invention utilizes nickel, chrome ore to produce the second preferred embodiment of the method for austenite stainless steel;
Fig. 3 is a schema, illustrates that the present invention utilizes nickel, chrome ore to produce the 3rd preferred embodiment of the method for austenite stainless steel.
Embodiment
Below in conjunction with drawings and Examples, the present invention is described in detail.
Before the present invention is described in detail, it should be noted that in the following description content, wt% is weight percentage.
Consult Fig. 1, for the present invention utilizes nickel, chrome ore to produce the first preferred embodiment of the method for austenite stainless steel, comprise:
Step 21, sends a dry kiln to by nickel minerals, the drying temperature of this dry kiln is 600 to 700 DEG C, and free water in nickel minerals is reduced to 10-20% by 30-35%.Carry out fragmentation afterwards, sieve, a rotary kiln baking is delivered to again after batch mixing, maturing temperature be 800 DEG C to 950 DEG C to remove free water in nickel minerals and crystal water, coordinating reductive agent (hard coal) together to drop in roasting process to carry out prereduction becomes nickel slag, nickel slag after roasting drops into a thermal mineral furnace melting again, obtain raw nickel matte molten iron, mobility due to slag affects the effect that scum is separated, strict must control the tapping temperature about 1400 DEG C to 1500 DEG C of temperature about 1550 DEG C to 1650 DEG C that slag comes out of the stove and raw nickel matte molten iron, the chemical composition now obtaining raw nickel matte molten iron is Ni:8-15wt%, C<4wt%, Si<2wt%, P<0.06wt%.
Step 22, by chrome ore (Cr
2o
3content is less than 62wt%) and the mixing of coke powder, through ball press, chrome ore is made pelletizing, and remove moisture with dryer, send into a process furnace sintering afterwards, at temperature 1350 DEG C to 1450 DEG C, reduction sintering chrome ore is sintered into through process furnace, reduction sintering chrome ore and coke grain send into a mineral hot furnace melting more afterwards, send into the granularity of the reduction sintering chrome ore of mineral hot furnace for being less than 30mm, and the tapping temperature controlling slag is 1600 to 1700 DEG C obtains chromium hot melt, the chemical composition of the chromium hot melt of output is Cr<60wt%, C<9wt%, Si<5wt%, P<0.03wt%.
Step 23, drops into converter by the mode that described raw nickel matte molten iron, chromium hot melt send with heat, smelts into molten stainless steel.
Step 24, makes steel billet by molten stainless steel with continuous caster.
Because converter steelmaking to become the processing procedure of steel billet with continuous caster continuous casting, by person of ordinary skill in the field be can easily understand that, no longer add to describe in detail at this.The raw nickel matte molten iron of different ratios, chromium hot melt and make the stainless steel grade of different series can be dropped in the present embodiment according to the composition in stainless steel, as nickel in the stainless steel chemical component of SUS202 system be 4-6wt%, chromium is 17-19wt%, and in the stainless steel chemical component of SUS304 system, nickel is 8-10.5wt%, chromium is 17.5-19.5wt%.
For the nickel content in the raw nickel matte molten iron obtained after melting be 8wt%, the chromium content 50wt% of chromium hot melt, in the total amount of the nickel dropped into, chromium hot melt, raw nickel matte molten iron accounts for 65wt%, chromium hot melt accounts for 35wt%, then can prepare the stainless steel that the meets SUS202 system content demand at chromium, nickel.And for nickel content in the raw nickel matte molten iron obtained after melting be 15wt%, the chromium content of chromium hot melt is for 40wt%, in the total amount of the nickel dropped into, chromium hot melt, raw nickel matte molten iron accounts for 55wt%, chromium hot melt accounts for 45wt%, then can prepare the stainless steel that the meets SUS304 system content demand at chromium, nickel.
According to above-mentioned processing procedure, utilize rotary kiln by nickel minerals pre-reduction treatment, to remove free water in nickel minerals and crystal water becomes nickel slag, and utilize process furnace first to become reduction sintering chrome ore to chrome ore pre-reduction treatment, after again nickel slag and reduction sintering chrome ore being used mineral hot furnace melting respectively, form raw nickel matte molten iron and chromium hot melt respectively, the ratio of metal ingredient easily controls, required input proportioning can be grasped, and raw nickel matte molten iron and the direct heat of chromium hot melt deliver to converter to produce austenite stainless steel, compare conventional process and reduce the number of times repeating melting, relatively reduce fuel and power consumption, cost control has advantage, earning capacity can be increased, improve the market competitiveness.
Consult Fig. 2, for the present invention utilizes nickel, chrome ore to produce the second preferred embodiment of the method for austenite stainless steel, comprise:
Step 31, nickel minerals is carried out fragmentation, adds water and size mixing, and be uniformly mixed under hyperbaric environment with sulphuric acid soln, the solid-to-liquid ratio that wherein this nickel minerals mixes with sulphuric acid soln is 1:4, and in the environment of pressure 4-5MPa, temperature 250 DEG C to 300 DEG C mix and blend, then filter out the mineral finished fluid containing nickel, cobalt, this is nickeliferous, the mineral finished fluid of cobalt electrolytically show that nickel content is greater than the electrolytic nickel of 99wt% again, and cobalt metal.In the present embodiment, the rate of recovery of metallic nickel and cobalt metal can reach more than 90%.
Step 32, by chrome ore (Cr
2o
3content is less than 62wt%) and the mixing of coke powder, through ball press, chrome ore is made pelletizing, and remove moisture with dryer, send into a process furnace sintering afterwards, at temperature 1350 to 1450 DEG C, reduction sintering chrome ore is sintered into through process furnace, reduction sintering chrome ore and coke grain send into a mineral hot furnace melting again, and the granularity of the reduction sintering chrome ore of feeding mineral hot furnace is for being less than 30mm, and obtain chromium hot melt at controlling the tapping temperature 1600 DEG C to 1700 DEG C of slag, the chemical composition of the chromium hot melt of output is Cr<60wt%, C<9wt%, Si<5wt%, P<0.03wt%.
Step 33, by described electrolytic nickel through belt conveyor to converter feed bin, and coordinate the mode that chromium hot melt send with heat, drop into converter, smelt into molten stainless steel.
Step 34, makes steel billet by molten stainless steel with continuous caster.
Because converter steelmaking to become the processing procedure of steel billet with continuous caster continuous casting, by person of ordinary skill in the field be can easily understand that, no longer add to describe in detail at this.The electrolytic nickel of different ratios, chromium hot melt and make the stainless steel grade of different series can be dropped in the present embodiment according to the composition in stainless steel, as nickel in the stainless steel chemical component of SUS202 system be 4-6wt%, chromium is 17-19wt%, and in the stainless steel chemical component of SUS304 system, nickel is 8-10.5wt%, chromium is 17.5-19.5wt%.
For the nickel content of electrolytic nickel be 99wt%, the chromium content of chromium hot melt is for 24wt% and useless carbon steel, in the total amount of the electrolytic nickel dropped into, chromium hot melt and useless carbon steel, electrolytic nickel accounts for 5wt%, chromium hot melt accounts for 75wt% and useless carbon steel accounts for 20wt%, then can prepare the content demand of chromium, nickel in the stainless steel meeting SUS202 system.In the total amount of the electrolytic nickel dropped into, chromium hot melt and useless carbon steel, electrolytic nickel accounts for 9wt%, chromium hot melt accounts for 76wt% and useless carbon steel accounts for 15wt%, then can prepare the stainless steel that the meets SUS304 system content demand at chromium, nickel.
The electrolytic nickel of different ratios, chromium hot melt and useless carbon steel can be dropped into equally according to the composition in stainless steel in the second preferred embodiment, except having except identical effect with the first preferred embodiment, when electrolytically drawing electrolytic nickel, cobalt metal can be obtained simultaneously, and therefore can reclaim the cobalt metal of high value, increase the added economic value of overall process, relatively more can save cost.
Consult Fig. 3, for the present invention utilizes nickel, chrome ore to produce the 3rd preferred embodiment of the method for austenite stainless steel, comprise:
Step 41, is distinguished into a low grade nickel ore by nickel raw ore material through ore dressing, and a higher-grade nickel minerals, and the nickel content wherein in low grade nickel ore is less than 1.5wt%, and the nickel content in higher-grade nickel minerals is not less than 1.5wt%.
Step 42, low grade nickel ore is carried out fragmentation, adds water and size mixing, and mix with sulphuric acid soln, the solid-to-liquid ratio that wherein this low grade nickel ore mixes with sulphuric acid soln is 1:4, and in the environment of pressure 4-5MPa, temperature 250 DEG C to 300 DEG C mix and blend, filter out the mineral finished fluid containing nickel, cobalt afterwards, this is nickeliferous, the mineral finished fluid of cobalt electrolytically show that nickel content is greater than the electrolytic nickel of 99wt% again, and cobalt metal.
Step 43, higher-grade nickel minerals is sent to a dry kiln, the drying temperature of this dry kiln is 600 to 700 DEG C, the free water of higher-grade nickel minerals is reduced to 10-20% by 30-35%, carry out fragmentation afterwards, sieve, a rotary kiln baking is delivered to again after batch mixing, maturing temperature is 800 DEG C to 950 DEG C, to remove free water in higher-grade nickel minerals and crystal water, coordinating reductive agent (hard coal) together to drop in roasting process to carry out prereduction becomes nickel slag, nickel slag after roasting drops into a mineral hot furnace melting again, obtain raw nickel matte molten iron, mobility due to slag affects the effect that scum is separated, strict must control the tapping temperature about 1400 DEG C to 1500 DEG C of temperature about 1550 to 1650 DEG C that slag comes out of the stove and raw nickel matte molten iron, the chemical composition now obtaining raw nickel matte molten iron is Ni:8-15wt%, C<4wt%, Si<2wt%, P<0.06wt%.
Step 44, by chrome ore (Cr
2o
3content is less than 62wt%) and the mixing of coke powder, through ball press, chrome ore is made pelletizing, and remove moisture with dryer, send into a process furnace sintering afterwards, at temperature 1350 to 1450 DEG C, reduction sintering chrome ore is sintered into through process furnace, reduction sintering chrome ore and coke grain send into a mineral hot furnace melting more afterwards, and the granularity of the reduction sintering chrome ore of feeding mineral hot furnace is for being less than 30mm, and obtain chromium hot melt at controlling the tapping temperature 1600 to 1700 DEG C of slag, the chemical composition of the chromium hot melt of output is Cr<60wt%, C<9wt%, Si<5wt%, P<0.03wt%.
Step 45, by described electrolytic nickel through belt conveyor to converter batch bin, and the mode coordinating raw nickel matte molten iron, chromium hot melt to send with heat drops into converter, smelts into molten stainless steel.
Step 46, makes steel billet by molten stainless steel with continuous caster.
Because converter steelmaking to become the processing procedure of steel billet with continuous casting, by person of ordinary skill in the field be can easily understand that, no longer add to describe in detail at this.The raw nickel matte molten iron of different ratios or electrolytic nickel, chromium hot melt and make the stainless steel grade of different series can be dropped in the present embodiment according to the composition in stainless steel, as nickel in the stainless steel chemical component of SUS202 system be 4-6wt%, chromium is 17-19wt%, and in the stainless steel chemical component of SUS304 system, nickel is 8-10.5wt%, chromium is 17.5-19.5wt%.
For the nickel content in the raw nickel matte molten iron obtained after melting be 8wt%, the chromium content of chromium hot melt is for 50wt%, in the raw nickel matte molten iron of input and the total amount of chromium hot melt, raw nickel matte molten iron accounts for 65wt%, chromium hot melt accounts for 35wt%, then can prepare the stainless steel that the meets SUS202 system content demand at chromium, nickel.For the nickel content of electrolytic nickel be 99wt%, the nickel content of raw nickel matte molten iron is 10wt%, the chromium content of chromium hot melt is for 50wt%, in the total amount of the electrolytic nickel dropped into, raw nickel matte molten iron and chromium hot melt, electrolytic nickel accounts for 2wt%, raw nickel matte molten iron accounts for 62wt% and chromium hot melt accounts for 36wt%, then can prepare the stainless steel that the meets SUS304 system content demand at chromium, nickel.
In the 3rd preferred embodiment, in conjunction with the first preferred embodiment and the second preferred embodiment, first effectively classification is done to nickel raw ore material, use, select low grade nickel ore and higher-grade nickel minerals respectively, the mode being the refining of employing wet type at low grade nickel ore obtains electrolytic nickel, rotary kiln baking is adopted to obtain raw nickel matte molten iron with mineral hot furnace melting again at higher-grade nickel minerals, composition depending on nickel raw ore material can do the allotment optimized, production elasticity is large, do not need the quality being limited to mineral aggregate, procedure for producing has better elasticity and configuration, also can reclaim the cobalt metal of high economic worth simultaneously, increase cost advantage and enhance competitiveness.
In sum, the present invention utilizes nickel, the method of austenite stainless steel produced by chrome ore, wet type refining route is adopted at low grade nickel ore, output cobalt metal and highly purified electrolytic nickel respectively, the cobalt metal reclaimed can sell outward increase economic worth, electrolytic nickel directly drops into converter smelting with Belt Conveying, and higher-grade nickel minerals utilizes rotary kiln pre-reduction treatment, removal free water and crystal water become nickel slag, and chrome ore utilizes process furnace pre-reduction treatment to become reduction sintering chrome ore equally, after again the nickel slag after roasting and reduction sintering chrome ore being dropped into mineral hot furnace melting respectively afterwards, output raw nickel matte molten iron and chromium hot melt respectively, directly heat sends into converter producing austenite stainless steel again, production there is preferably combined elastic, and reduce the consumption of the energy, cost control has best advantage, improve market competitiveness.
Claims (3)
1. utilize nickel, chrome ore to produce a method for austenite stainless steel, it is characterized in that: this method utilizing nickel, chrome ore to produce austenite stainless steel comprises following steps:
A nickel raw ore material is distinguished into a low grade nickel ore through ore dressing by (), and a higher-grade nickel minerals, and the nickel content wherein in low grade nickel ore is less than 1.5wt%, and the nickel content in higher-grade nickel minerals is not less than 1.5wt%;
B low grade nickel ore is carried out fragmentation, adds water and size mixing by (), and after mixing with sulphuric acid soln and the mineral finished fluid filtered out containing nickel, cobalt, this is nickeliferous, the mineral finished fluid of cobalt electrolytically draws electrolytic nickel and cobalt metal again;
C higher-grade nickel minerals is carried out fragmentation, sieves by (), deliver to a rotary kiln baking after batch mixing to remove free water in higher-grade nickel minerals and crystal water, coordinating reductive agent together to drop in roasting process to carry out prereduction becomes nickel slag, and the nickel slag after roasting obtains raw nickel matte molten iron by a mineral hot furnace melting again;
D () sinters chrome ore into reduction sintering chrome ore through a process furnace, reduction sintering chrome ore and coke grain are sent into a mineral hot furnace melting again and obtained chromium hot melt;
(e) by described electrolytic nickel with Belt Conveying to converter feed bin, and the mode coordinating raw nickel matte molten iron, chromium hot melt to send with heat drops into converter, smelts into molten stainless steel; And
F molten stainless steel is made steel billet with continuous caster by ().
2. the method utilizing nickel, chrome ore to produce austenite stainless steel according to claim 1, it is characterized in that: in step (c), the maturing temperature of this rotary kiln is 800 DEG C to 950 DEG C, and the tapping temperature of this raw nickel matte molten iron is 1400 DEG C to 1500 DEG C in mineral hot furnace; In step (d), chrome ore also mixes with coke powder by this chrome ore before sintering, makes pelletizing through ball press, and removes moisture with dryer, just sends into process furnace sintering, and the granularity of the reduction sintering chrome ore of feeding mineral hot furnace is for being less than 30mm.
3. the method utilizing nickel, chrome ore to produce austenite stainless steel according to claim 1, it is characterized in that: in step (c), higher-grade nickel minerals carries out fragmentation, sieves, be first send a dry kiln to before batch mixing, to remove the free water in higher-grade nickel minerals.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW101123242 | 2012-06-28 | ||
| TW101123242A TW201400624A (en) | 2012-06-28 | 2012-06-28 | Method for producing austenitic stainless steel with nickel and chromium ore |
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| CN103509934A CN103509934A (en) | 2014-01-15 |
| CN103509934B true CN103509934B (en) | 2016-04-27 |
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| CN201210336287.6A Active CN103509934B (en) | 2012-06-28 | 2012-09-12 | Method for producing austenitic stainless steel by using nickel and chromium ores |
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| US (1) | US20140000834A1 (en) |
| EP (1) | EP2679691B1 (en) |
| JP (1) | JP5778215B2 (en) |
| CN (1) | CN103509934B (en) |
| AU (1) | AU2013206521B2 (en) |
| ES (1) | ES2728922T3 (en) |
| PH (1) | PH12013000179A1 (en) |
| SI (1) | SI2679691T1 (en) |
| TW (1) | TW201400624A (en) |
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| CN103146983B (en) * | 2013-03-18 | 2016-03-23 | 莱芜钢铁集团有限公司 | A kind of method utilizing the production of thick ferronickel to contain nickel steel |
| CN103866076B (en) * | 2014-04-01 | 2016-01-27 | 重庆大学 | A kind of compact type production method of austenitic stainless steel |
| US10081849B2 (en) * | 2014-08-11 | 2018-09-25 | Flsmidth A/S | System and methods for optimizing the efficiency of smelting copper concentrates |
| CN106893946A (en) * | 2017-03-06 | 2017-06-27 | 广东广青金属科技有限公司 | Using the low-carbon (LC) austenitic stainless steel including molybdenum and its production technology of smelting laterite-nickel ores |
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| Publication number | Publication date |
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| JP2014009403A (en) | 2014-01-20 |
| JP5778215B2 (en) | 2015-09-16 |
| EP2679691A1 (en) | 2014-01-01 |
| TW201400624A (en) | 2014-01-01 |
| CN103509934A (en) | 2014-01-15 |
| TWI464277B (en) | 2014-12-11 |
| AU2013206521A1 (en) | 2014-01-16 |
| AU2013206521B2 (en) | 2016-03-17 |
| US20140000834A1 (en) | 2014-01-02 |
| PH12013000179B1 (en) | 2015-12-02 |
| SI2679691T1 (en) | 2019-07-31 |
| EP2679691B1 (en) | 2019-04-17 |
| ES2728922T3 (en) | 2019-10-29 |
| PH12013000179A1 (en) | 2015-12-02 |
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