CN102268509A - Intermediate frequency furnace and arc furnace combined melting method - Google Patents

Intermediate frequency furnace and arc furnace combined melting method Download PDF

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CN102268509A
CN102268509A CN2011101861004A CN201110186100A CN102268509A CN 102268509 A CN102268509 A CN 102268509A CN 2011101861004 A CN2011101861004 A CN 2011101861004A CN 201110186100 A CN201110186100 A CN 201110186100A CN 102268509 A CN102268509 A CN 102268509A
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intermediate frequency
furnace
arc furnace
electric arc
steel
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周伟
金凤奎
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Baoshan Iron and Steel Co Ltd
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Baoshan Iron and Steel Co Ltd
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Abstract

The invention relates to an intermediate frequency furnace and arc furnace combined melting method, which comprises the following steps of: (1) charging steel materials in an intermediate frequency furnace, and discharging to obtain 1,520-1,530DEG C molten steel, wherein the steel materials are calculated according to a non-oxidizing process for an arc furnace, 8 to 12 percent of cast iron can be mixed generally, and 0.40 to 0.60 percent of end point carbon is added preferably; and (2) adding lime into the arc furnace, adding the molten steel, heating, removing phosphorus and carbon, and tapping, and performing a refining process. An intermediate frequency furnace and arc furnace combined melting process is adopted, the melting time is shortened, the cost and comprehensive energy consumption are reduced, the occupied area is small, the investment is low, pollutant emission is low, and an environment-friendly steelmaking flow is realized; and compared with the traditional arc furnace smelting process, the combined process has the advantages of saving comprehensive cost and reducing comprehensive energy consumption.

Description

A kind of intermediate frequency furnace electric arc furnace duplex smelting process
Technical field
The invention belongs to the electric arc furnace smelting field, particularly a kind of intermediate frequency furnace electric arc furnace duplex smelting process.
Background technology
Intermediate frequency furnace is a kind of supply unit that power frequency 50HZ alternating-current is changed into intermediate frequency (300HZ is above to 1000HZ), the three-phase main-frequency alternating-current, become direct current after the rectification, again direct current is become adjustable electric current of intermediate frequency, supply is by the intermediate frequency exchange current that flows through in electric capacity and the ruhmkorff coil, in induction coil, produce highdensity magnetic line of force, and the metallic substance that holds in the cutting induction coil, very big eddy current in metallic substance, produced.
Intermediate frequency furnace has that rate of heating is fast, production efficiency is high, the advantage that charcoal is few, save material and cost is taken off in oxidation, and becomes prolongation die life.Because the principle of Frequency Induction Heating is an electromagnetic induction, its heat self produces in workpiece, and the common laborer need not burn the stove workman and burn stove and banking work in advance with the go to work non-stop run of the task of can forging in back ten minutes of middle frequency furnace.Because this type of heating heat-up rate is fast, so oxidation is few, the oxidization burning loss of heating in medium frequency forging only is 0.5%, the oxidization burning loss of gas furnace heating is 2%, coal furnace reaches 3%, and heating in medium frequency technology material-saving, forging per ton are compared with coal-fired stove and saved steel starting material 20-50 kilogram at least.Its material use efficiency can reach 95%.Because this type of heating homogeneous heating, the core table temperature difference is minimum, so also increased the life-span of forging die greatly aspect forging, the roughness on forging surface is also less than the 50um energy saving technology, heating in medium frequency is than heavy oil heating and energy saving 31.5%~54.3%, than coal gas heating and energy saving 5%~40%.Heating quality is good, and the rate 1.5% of can reducing the number of rejects and seconds boosts productivity 10%~30%, prolongs die life 10%~15%.
But intermediate frequency furnace melting electric consumption height, bad dephosphorization.
Electric arc furnace (electric arc furnace) is to utilize the high melt ore of electrode arc generation and the electric furnace of metal.Energy was very concentrated when geseous discharge formed electric arc, and arc district temperature is more than 3000 ℃.For smelting metal, electric arc furnace is bigger than other steel melting furnace technological flexibilities, can remove impurity such as desulfuration, phosphorus effectively, and furnace temperature is controlled easily, and occupation area of equipment is little, is suitable for the melting of superior alloy steel.
Along with the improvement of arc furnace equipment and the raising of smelting technology, development of electric power industry, the cost of electric-arc furnace steelmaking constantly descends, electric-arc furnace steelmaking not only is used to produce steel alloy now, and be used for producing general carbon steel in a large number, the proportion of its output in major industrial country's steel ultimate production constantly rises.
But the iron and steel stock of electric arc furnace smelting consumes high.
In sum, existing intermediate frequency furnace is smelted advantage: iron and steel stock, yield of alloy height, and existing electric arc furnace smelting advantage: dephosphorization is fast, quick heating; Existing intermediate frequency furnace is smelted shortcoming: power consumption height, bad dephosphorization, existing electric arc furnace smelting shortcoming: iron and steel stock consumes high.
It is a kind of steel-smelting technology that generally adopts both at home and abroad at present that electric arc furnace and LF ladle refining furnace coupling are smelted.For electric furnace hot metal charge producer, because favourable condition (electric furnace improves the production practice of hot metal charge ratio, bao steel technology, 2009 the 6th phases for Jin Fengkui, Zhou Wei etc.) has been created in improving constantly of hot metal ratio to reducing cost.And for the electric arc furnace that does not adopt liquid iron charging technology, owing to need allocate a certain amount of carbon (being generally 30% pig-iron charge) into and flux for oxygen blast, not only make burden structure cost height, and because iron and steel stock consumption higher relatively (being generally about 1120kg/t), cost is high about 150 yuan/ton than bof process.Therefore, this flow process steel-making enterprise is had difficulty in taking a step in the present circumstance.
Part steel mill adopts intermediate frequency furnace to smelt and substitutes electric arc furnace for addressing this problem, and iron and steel stock and yield of alloy are all higher, but the problem that adopts this technology to bring is: the bad oxygen blast dephosphorization of intermediate frequency furnace causes the demanding steel grade of some phosphorus to be restricted.
Yang Lizhong, LF stove and intermediate frequency furnace duplex are smelted high quality steel process practice, Shanxi metallurgy, 2010, No.3.
Summary of the invention
Technical problem to be solved by this invention provides a kind of intermediate frequency furnace electric arc furnace duplex smelting process, and this method has reduced cost, has reduced comprehensive power consumption, is fit to scale operation.
The technical process of a kind of intermediate frequency furnace electric arc furnace duplex smelting process of the present invention comprises:
Steel scrap (comprising the part foundry goods) → intermediate frequency furnace → electric arc furnace → LF stove → VD stove → continuous casting.
A kind of intermediate frequency furnace electric arc furnace duplex smelting process of the present invention comprises:
(1) iron and steel stock is packed in the intermediate frequency furnace, come out of the stove 1520-1530 ℃ of molten steel, wherein iron and steel stock carries out according to electric arc furnace non-oxidizing process burden calculation method, generally can allocate into according to 8-12% cast iron, end point carbon is advisable by 0.40%-0.60%;
(2) in electric arc furnace, add lime, add above-mentioned molten steel then, heat up, dephosphorization, decarburization, tapping at last enters the refining program.
Step (1) is described packs iron and steel stock before the intermediate frequency furnace into, earlier lime is added the intermediate frequency furnace bottom, treat described slag charge all melt form liquid state after, add insulating covering agent on top.
The consumption of above-mentioned lime is a 10kg steel per ton, and the consumption of insulating covering agent is a 1kg steel per ton.
The iron and steel stock of packing into described in the step (1) is distributed in infusible foundry goods etc. in the middle part of the body of heater, and steel scrap is distributed in the bottom and the top of body of heater.
The preferred mass ratio that cast iron described in the step (1) is allocated into is 10%.
Adding lime described in the step (2) adds for pressing 40-45kg/t.
When adding above-mentioned molten steel described in the step (2), the temperature of molten steel is 1520-1530 ℃.
The present invention changes the processing route that at present simple intermediate frequency furnace is smelted or electric arc furnace smelting provides crude molten steel merely, use intermediate frequency furnace and electric arc furnace duplex to smelt crude molten steel is provided, the carbon content of molten steel that intermediate frequency furnace is come out by rational batching remains on the scope of 0.40-0.60%, pour electric arc furnace into after 1520-1530 ℃ of tapping of this molten steel, carrying out tapping after the decarburization dephosphorization is rapidly heated enters the refining program.
By changing traditional processing method, promptly both lower by the characteristics assurance iron and steel stock consumption of intermediate frequency furnace smelting non-oxidation, obtain low-phosphorus molten steel by electric arc furnace smelting again and smelt the high-quality crude molten steel.It is safe and reliable to use the present invention to make steel, and cost is low, and energy consumption is low, and economic and social benefit is good
The present invention is directed to present all cold charge electric arc furnace smelting technology, propose a kind of intermediate frequency furnace electric arc furnace two-link smelting process, analyze its feasibility, introduced the related process scheme, cost and process energy consumption have been carried out analyzing relatively.
The present invention increases an intermediate frequency furnace that is equal to capacity of electric arc furnace before an electric arc furnace operation.In the intermediate frequency furnace, before charging, earlier slag charges such as lime are added people's intermediate frequency furnace bottom, guarantee that slag charge can melt as early as possible, after treating that slag charge all melts the formation molten slag, add insulating covering agent on slag top, it is dried to avoid the later stage to occur sending electric power reduction, slag to return, to realize the covering effect of slag to molten steel.
Medium-frequency induction furnace power density melting capacity per ton is brought up to 1000kW, can make melting period shorten to 35min.Like this, intermediate frequency furnace smelting rhythm can be complementary with ultra-high power electric arc furnace fully.Because medium-frequency induction furnace electrical efficiency and thermo-efficiency height have not only improved melting rate, have shortened fusing time, and have made the corresponding reduction of its unit power consumption.5 tons of medium-frequency induction furnaces, average energy consumption 525kwh/t.For steel-making enterprise, because capacity is bigger, continuous production estimates that its average energy consumption is lower.
The two-link smelting process effect analysis:
1, cost analysis: Li Shiqi etc. (Li Shiqi, Yu Jian, Chen Ze etc., the research of all cold charge electric arc furnace smelting material energy state, special steel proceeding in 2008) have studied the index situation of certain all cold charge steel mill, see the following form 1:
Certain factory's electric arc furnace smelting leading indicator of table 1
After using intermediate frequency furnace melting steel scrap, the leading indicator of expectation sees Table 2:
Table 2 is estimated index
Figure BDA0000073690670000032
As seen, behind intermediate frequency furnace and electric arc furnace two-link smelting process, smelting cycle dropped to 35 minutes from 67 minutes, and output can significantly rise, and power consumption slightly rises, and other consumption all decline to a great extent.Cost as calculated drops to:
Power consumption rising expense: (555-332) * 0.65=144.95 unit/ton 1.
Iron and steel stock decline expense: (1094-1040) * 3000/1000=162 unit/ton 2.
The expense that lime descends: (64-50) * 0.8=11.2 unit/ton 3.
The expense that electrode descends: (2.51-0.4) * 18.2=38.4 unit/ton 4.
The expense that oxygen descends: (60.38-20) * 0.5=20.2 unit/ton 5.
More than after several totals, decline expense always is:
2.+8.+4.+5.-1.=86.85 yuan of/ton, cost space descends bigger, is worth attempting.
2, process energy consumption analysis: the electric furnace operation is owing to need to add the part pig iron, and process energy consumption is higher before the electric furnace, energy consumption data such as table 3 before the domestic steel that Li Shiqi etc. collect:
Process energy consumption kgce/t before the steel-making of table 3 contrast electric furnace steel mill
Figure BDA0000073690670000042
According to last table data, then adopt duplex technology to reduce by 30% pig iron and cut down the consumption of energy and be 218.96kgce/t.
Because adopt duplex technology power consumption to rise, the energy consumption of increase is: 23*0.1229=2.8267kgce/t
Because adopt duplex technology oxygen depletion to descend, the energy consumption of reduction is: 40.38*0.4=16.152kgce/t
Overall energy consumption drops to: 218.96+16.152-2.827=232.285kgce/t
Beneficial effect
1, the present invention adopts intermediate frequency furnace to add the electric arc furnace two-link smelting process, shortens smelting time, reduces cost, and reduces comprehensive energy consumption, and floor space is less, invests lowlyer, and pollutant emission is low, is environmentally friendly steelmaking process.
2, after the present invention adopted duplex technology, comprehensive cost descended 86.85 yuan/ton, and comprehensive energy consumption is than conventional arc stove smelting technology decline 232.285kgce/t.
Embodiment
Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiment only to be used to the present invention is described and be not used in and limit the scope of the invention.Should be understood that in addition those skilled in the art can make various changes or modifications the present invention after the content of having read the present invention's instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.
Embodiment 1
(1) iron and steel stock is packed in the intermediate frequency furnace, come out of the stove 1580-1620 ℃ of molten steel, wherein iron and steel stock carries out according to arc furnace non-oxidizing process burden calculation method, allocates into according to 10% cast iron, end point carbon is advisable by 0.50%;
(2) in electric arc furnace, add lime, add above-mentioned molten steel then, heat up, dephosphorization, decarburization, tapping at last enters the refining program.
Embodiment 2
(1) earlier the lime slag charge is added people's intermediate frequency furnace bottom, the iron and steel stock of packing into then, treat described slag charge all melt form molten slag after, add insulating covering agent on described molten slag top, coming out of the stove and obtaining temperature is 1520-1530 ℃ of molten steel; Wherein prepare burden medium cast iron by 10%, and end point carbon is allocated into by 0.50%; When packing iron and steel stock into, infusible foundry goods etc. is distributed in the middle part of the body of heater, steel scrap is distributed in the bottom and the top of body of heater;
(2) in electric arc furnace, press 40kg/t and add lime, add above-mentioned molten steel (temperature is 1520-1530 ℃) then, heat up, dephosphorization, decarburization, tapping at last enters the refining program.
Embodiment 3
Following institute example: 70 tons of electric arc furnace of certain factory, first wife's 30% pig iron, 70% steel scrap, iron and steel stock consumes 1120kg/t, energy consumption of electric furnace 320kwh/t.After using patent technology of the present invention instead, prepare burden all with steel scrap (wherein 10% left and right sides foundry goods), intermediate frequency furnace power consumption 600kwh/t, energy consumption of electric furnace 50kwh/t, iron and steel stock consumes 1050kg/t.Then main consumption reduced:
Reduce expense without the pig iron: 1120*0.3*300/1000=100.8 unit/ton
Reduce iron and steel consumption and reduce expense: 70/1000*3200=224 unit/ton
Power consumption rising expense: 330*0.62=204 unit/ton
Comprehensive reduction expense: 100.8+224-204=120.8 unit/ton (other reduce lime, oxygen, consumption of electrode etc. and all do not calculate).

Claims (7)

1. intermediate frequency furnace electric arc furnace duplex smelting process comprises:
(1) iron and steel stock is packed in the intermediate frequency furnace, come out of the stove 1520-1530 ℃ of molten steel, wherein prepare burden and carry out according to electric arc furnace non-oxidizing process burden calculation method, allocate into according to 8-12% cast iron, end point carbon is 0.40%-0.60%;
(2) in electric arc furnace, add lime, add above-mentioned molten steel then, heat up, dephosphorization, decarburization, tapping at last enters the refining program.
2. a kind of intermediate frequency furnace electric arc furnace duplex smelting process according to claim 1, it is characterized in that: step (1) is described packs iron and steel stock before the intermediate frequency furnace into, earlier lime is added the intermediate frequency furnace bottom, treat described slag charge all melt form liquid state after, add insulating covering agent on top.
3. a kind of intermediate frequency furnace electric arc furnace duplex smelting process according to claim 2, it is characterized in that: the consumption of described lime is a 10kg steel per ton, the consumption of insulating covering agent is a 1kg steel per ton.
4. a kind of intermediate frequency furnace electric arc furnace duplex smelting process according to claim 1 is characterized in that: when packing iron and steel stock into described in the step (1), the infusible foundry goods is distributed in the body of heater middle part, steel scrap is distributed in the bottom and the top of body of heater.
5. a kind of intermediate frequency furnace electric arc furnace duplex smelting process according to claim 1, it is characterized in that: the mass ratio of the cast iron described in the step (1) is 10%.
6. a kind of intermediate frequency furnace electric arc furnace duplex smelting process according to claim 1 is characterized in that: the adding lime described in the step (2) adds for pressing 40-45kg/t.
7. a kind of intermediate frequency furnace electric arc furnace duplex smelting process according to claim 1 is characterized in that: when adding above-mentioned molten steel described in the step (2), the temperature of molten steel is 1520-1530 ℃.
CN2011101861004A 2011-07-05 2011-07-05 Intermediate frequency furnace and arc furnace combined melting method Pending CN102268509A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105132618A (en) * 2015-08-28 2015-12-09 中钢集团邢台机械轧辊有限公司 Molten steel smelting method
CN105969941A (en) * 2015-12-15 2016-09-28 海安海太铸造有限公司 Method for producing high-performance steel casting material by co-smelting with arc furnace and medium-frequency furnace
CN107326150A (en) * 2017-06-16 2017-11-07 北京科技大学 A kind of production method of full steel scrap electric arc furnaces duplex Clean Steel Smelting
US10767239B2 (en) 2017-06-16 2020-09-08 University Of Science And Technology Beijing Production method for smelting clean steel from full-scrap steel using duplex electric arc furnaces

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CN102072653A (en) * 2011-01-14 2011-05-25 杭州因达电炉有限公司 Electric arc induction furnace and smelting control method

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RU2325960C2 (en) * 2005-09-22 2008-06-10 Белорусский Национальный Технический Университет Method of manufacture of commercial products at casting and rolling complex of metallurgical mini plant
CN102072653A (en) * 2011-01-14 2011-05-25 杭州因达电炉有限公司 Electric arc induction furnace and smelting control method

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105132618A (en) * 2015-08-28 2015-12-09 中钢集团邢台机械轧辊有限公司 Molten steel smelting method
CN105969941A (en) * 2015-12-15 2016-09-28 海安海太铸造有限公司 Method for producing high-performance steel casting material by co-smelting with arc furnace and medium-frequency furnace
CN107326150A (en) * 2017-06-16 2017-11-07 北京科技大学 A kind of production method of full steel scrap electric arc furnaces duplex Clean Steel Smelting
CN107326150B (en) * 2017-06-16 2018-04-03 北京科技大学 A kind of production method of full steel scrap electric arc furnaces duplex Clean Steel Smelting
WO2018227836A1 (en) * 2017-06-16 2018-12-20 北京科技大学 Method for producing clean steel by means of electric arc furnace dual smelting of full scrap steel
US10767239B2 (en) 2017-06-16 2020-09-08 University Of Science And Technology Beijing Production method for smelting clean steel from full-scrap steel using duplex electric arc furnaces

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Application publication date: 20111207