CN113699308A - One-time combustion auxiliary heating electric arc furnace steelmaking equipment and method - Google Patents
One-time combustion auxiliary heating electric arc furnace steelmaking equipment and method Download PDFInfo
- Publication number
- CN113699308A CN113699308A CN202111098608.9A CN202111098608A CN113699308A CN 113699308 A CN113699308 A CN 113699308A CN 202111098608 A CN202111098608 A CN 202111098608A CN 113699308 A CN113699308 A CN 113699308A
- Authority
- CN
- China
- Prior art keywords
- scrap steel
- layer
- electric arc
- furnace
- arc furnace
- 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.)
- Granted
Links
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 88
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000010438 heat treatment Methods 0.000 title claims abstract description 26
- 238000009845 electric arc furnace steelmaking Methods 0.000 title claims abstract description 12
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 220
- 239000010959 steel Substances 0.000 claims abstract description 220
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 63
- 239000007789 gas Substances 0.000 claims abstract description 61
- 239000003546 flue gas Substances 0.000 claims abstract description 49
- 239000000463 material Substances 0.000 claims abstract description 27
- 230000002829 reductive effect Effects 0.000 claims abstract description 21
- 238000007599 discharging Methods 0.000 claims abstract description 15
- 230000009467 reduction Effects 0.000 claims abstract description 8
- 238000001816 cooling Methods 0.000 claims abstract description 5
- 238000010891 electric arc Methods 0.000 claims description 85
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 51
- 238000007789 sealing Methods 0.000 claims description 51
- 229910052760 oxygen Inorganic materials 0.000 claims description 29
- 239000001301 oxygen Substances 0.000 claims description 29
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 28
- 239000000779 smoke Substances 0.000 claims description 25
- 230000008569 process Effects 0.000 claims description 16
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 14
- 239000011819 refractory material Substances 0.000 claims description 12
- 238000000462 isostatic pressing Methods 0.000 claims description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 9
- 238000002347 injection Methods 0.000 claims description 8
- 239000007924 injection Substances 0.000 claims description 8
- 239000000428 dust Substances 0.000 claims description 7
- 238000009628 steelmaking Methods 0.000 claims description 7
- 230000007613 environmental effect Effects 0.000 claims description 6
- 239000003517 fume Substances 0.000 claims description 5
- 230000003647 oxidation Effects 0.000 claims description 5
- 238000007254 oxidation reaction Methods 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 4
- 238000002844 melting Methods 0.000 claims description 4
- 230000008018 melting Effects 0.000 claims description 4
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 3
- 230000004888 barrier function Effects 0.000 claims description 2
- 230000006835 compression Effects 0.000 claims description 2
- 238000007906 compression Methods 0.000 claims description 2
- 238000005520 cutting process Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 3
- 238000005272 metallurgy Methods 0.000 abstract description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 12
- 239000003245 coal Substances 0.000 description 11
- 238000003723 Smelting Methods 0.000 description 10
- 239000000446 fuel Substances 0.000 description 9
- 229910052799 carbon Inorganic materials 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 239000003345 natural gas Substances 0.000 description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 239000002893 slag Substances 0.000 description 5
- 239000002699 waste material Substances 0.000 description 5
- HGUFODBRKLSHSI-UHFFFAOYSA-N 2,3,7,8-tetrachloro-dibenzo-p-dioxin Chemical compound O1C2=CC(Cl)=C(Cl)C=C2OC2=C1C=C(Cl)C(Cl)=C2 HGUFODBRKLSHSI-UHFFFAOYSA-N 0.000 description 4
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000035699 permeability Effects 0.000 description 4
- 229910052717 sulfur Inorganic materials 0.000 description 4
- 239000011593 sulfur Substances 0.000 description 4
- 230000000903 blocking effect Effects 0.000 description 3
- 238000007664 blowing Methods 0.000 description 3
- 239000000571 coke Substances 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- FMMWHPNWAFZXNH-UHFFFAOYSA-N Benz[a]pyrene Chemical compound C1=C2C3=CC=CC=C3C=C(C=C3)C2=C2C3=CC=CC2=C1 FMMWHPNWAFZXNH-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000010079 rubber tapping Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 239000011701 zinc Substances 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- RHZUVFJBSILHOK-UHFFFAOYSA-N anthracen-1-ylmethanolate Chemical compound C1=CC=C2C=C3C(C[O-])=CC=CC3=CC2=C1 RHZUVFJBSILHOK-UHFFFAOYSA-N 0.000 description 1
- 239000003830 anthracite Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 210000000621 bronchi Anatomy 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000033764 rhythmic process Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Images
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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric 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
- C21C5/56—Manufacture of steel by other methods
- C21C5/562—Manufacture of steel by other methods starting from scrap
- C21C5/565—Preheating of scrap
-
- 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
- C21C2100/00—Exhaust gas
- C21C2100/04—Recirculation of the exhaust gas
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Furnace Details (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
The invention relates to a primary combustion auxiliary heating electric arc furnace steelmaking device and a method, belonging to the technical field of metallurgy. In order to distribute gas uniformly, the shaft furnace adopts an annular flue manifold to enter the furnace. The automatic steel scrap feeding device aims to solve the technical problems that a first layer of mechanical arm is high in bearing temperature and difficult in material selection due to the fact that a flue gas inlet channel and a steel scrap discharging channel are shared in the traditional steel scrap heating mode, potential safety hazards are caused due to the fact that water cooling is adopted, and mechanical arm bonding is easily caused due to the fact that steel scrap is melted. The effects of emission reduction and cost reduction are comprehensively realized, and the flue gas emission is ensured to reach the standard when the burning loss of the steel material is reduced.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to a one-time combustion auxiliary heating electric arc furnace steelmaking device and a method.
Background
China is the first major world-wide steel-producing country and is mainly based on long process. The carbon emission of the long-flow steel smelting process is far greater than that of the short-flow electric arc furnace smelting process, so that the long-flow process is gradually limited in future development of China and the short-flow process is encouraged to develop. However, the main electric power in China still comes from thermal power, and through secondary energy conversion, the energy utilization rate is low, the energy conversion rate of the thermal power is only about 40%, the emission is still large, and the waste heat of furnace gas of many traditional electric arc furnaces is not well utilized, so that the power consumption is higher, and the comprehensive carbon emission is still higher, and therefore, a low-carbon energy-saving short-process technology needs to be developed to improve the energy utilization rate.
At present, the electric arc furnace is also provided with a coal injection gun, but the aim is to make foamed slag; oxygen lances are also provided to accelerate the melting and heating of the scrap, but at the expense of the burning of the iron and steel charge. Therefore, the yield of the scrap steel metal is only about 90 percent.
At present, the treatment of a plurality of waste steel preheating tail gases also has problems, and sulfur, nitrate and dioxin are not treated, so that the emission exceeds the standard. The flue gas temperature fluctuation of the electric arc furnace is too large, and the current flue gas treatment technology cannot adapt to the flue gas of the electric arc furnace.
In order to solve the problems, a low-carbon and environment-friendly electric arc furnace smelting process and equipment are developed. Can obtain good energy-saving, low-carbon and environment-friendly effects.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide the primary combustion auxiliary heating electric arc furnace steelmaking equipment and the process, wherein primary energy in the electric arc furnace is added for combustion to supplement heat energy, the primary energy is adopted to replace secondary energy so as to obtain greater carbon reduction benefit, and the fuel is selected from coal or gas and the like and is determined according to local resource conditions. The traditional scrap heating is usually shared by a flue gas inlet channel and a scrap blanking channel. This results in high temperatures to which the first layer of robots are subjected and in difficult material choices. And the potential safety hazard is caused by adopting water cooling. Meanwhile, the molten scrap steel is easy to cause the adhesion of the manipulator. Therefore, scrap steel blanking and flue gas enter the shaft furnace to pass through by a lane. Namely, the flue gas is not discharged from the scrap steel blanking channel, and the flue gas independently enters the shaft furnace through the flue. In order to distribute gas uniformly, the shaft furnace adopts an annular flue manifold to enter the furnace.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides a one-time burning auxiliary heating electric arc furnace steelmaking equipment, preheats shaft furnace 2 including electric arc furnace 1 and the scrap steel that are connected, 1 top of electric arc furnace be equipped with the pipe 3 of discharging fume, the pipe 3 of discharging fume preheat shaft furnace 2 with the scrap steel and be connected.
Due to the defects of low geometric size height and small space of the electric arc furnace, the heat exchange time of combustion furnace gas is short, and the combustion heat cannot be fully utilized, which is the fundamental reason for restricting the combustion in the electric arc furnace. Therefore, the scrap steel preheating shaft furnace is additionally arranged behind the electric arc furnace, escaped high-temperature flue gas is used for heating the scrap steel, the exhaust gas temperature is reduced through heat exchange with the scrap steel, and the energy utilization rate is improved.
The temperature of the scrap steel entering the furnace is improved through scrap steel preheating, the melting time of the scrap steel is shortened, the smelting period is shortened, and the consumption of secondary energy-electricity is reduced.
The axial upper part of the furnace wall of the electric arc furnace 1 is evenly provided with a plurality of strong reducing gas nozzles 5 at intervals, and the axial lower part is evenly provided with a plurality of oxy-coal guns/oxy-fuel guns 4 at intervals.
The scrap steel preheating shaft furnace 2 comprises an upper vertical channel and a bottom inclined blanking channel, and the scrap steel preheating shaft furnace 2 is arranged obliquely above the electric arc furnace 1 and is connected with the electric arc furnace 1 through the inclined blanking channel.
The bottom of the scrap steel preheating shaft furnace 2 is provided with a rotary flap valve 8 which is provided with a locking bolt in a matching way.
The vertical section channel of the scrap steel preheating shaft furnace 2 is an N-section type preheating channel, and specifically comprises a first layer scrap steel preheating section, a second layer scrap steel preheating section, … and an N layer scrap steel preheating section from bottom to top, wherein N is 2-4.
The vertical section channel of the scrap steel preheating shaft furnace 2 is sequentially provided with a first layer of mechanical arm 10-1, a second layer of mechanical arm 10-2, … and an N-1 layer of mechanical arm from bottom to top, a layer of scrap steel preheating section is formed between the rotary flap valve 8 and the first layer of mechanical arm 10-1, a second layer of scrap steel preheating section is formed between the second layer of mechanical arm 10-2 and the first layer of mechanical arm 10-1, …, and N layers of scrap steel preheating sections are formed above the N-1 layer of mechanical arm.
One layer of scrap steel preheating section, the two layers of scrap steel preheating section and … in the shaft furnace section N-section type preheating channel of the scrap steel preheating shaft furnace 2, and the bottom of the side wall of the N-1 layer of scrap steel preheating section are respectively provided with an annular flue, one end of the annular flue is connected with the scrap steel preheating shaft furnace 2 through a branch gas pipe, and the other end of the annular flue is connected with a smoke exhaust pipe 3.
And a high-temperature-resistant and material-resistant valve 12 is arranged on the smoke exhaust pipe/connecting flue 3 connected with the annular flue at the bottom of the side wall of the preheating section of the layer 2 of scrap steel, and a secondary combustion chamber 13 is arranged between the high-temperature-resistant and material-resistant valve 12 and the annular flue.
Each layer of mechanical arm is used for supporting and supporting scrap steel, the static pressure of the scrap steel on the lower part is too large for avoiding the scrap steel material layer of the shaft furnace to be too high, the air permeability is deteriorated, and simultaneously, the scrap steel preheating shaft furnace 2 is provided with each layer of mechanical arms for heating the scrap steel layer by layer for the convenience of discharging. The number of layers is designed according to the capacity of the electric arc furnace, the variety of the common steel scraps and the bearing capacity of the manipulator. The three-layer example is used for describing the steel scrap layered preheating process as follows: in the operation process of the equipment, a first layer of scrap steel falls on the rotary flap valve 8 at the bottom of the furnace, a second layer of scrap steel is supported by a first layer of mechanical arm, a third layer of scrap steel is supported by a second layer of mechanical arm, the amount of each layer of scrap steel is designed according to one half of the charging amount of an electric arc furnace, and the scrap steel in each furnace is added twice.
And a secondary combustion section is arranged between the first layer of mechanical arm and the first layer of scrap steel material top, and a combustion-supporting gas injection system is arranged in a matching manner in the secondary combustion section.
And a combustion-supporting gas nozzle is arranged between the top of the first layer of waste steel and the bottom of the second layer of waste steel, a small oxygen combustion gun is arranged at the position and used as an igniter, and the oxygen combustion gun is far away from the manipulator as far as possible.
The flue gas temperature is the highest to be accepted to the first layer steel scrap, and when lower steel scrap heated to the softening temperature, because steel scrap softening deformation density increases, whole shaft furnace system resistance can increase, and when the resistance reached the settlement limit value, control system started and opened high temperature resistant refractory material valve 12 on the connection flue, and the vast majority of flue gas can directly get into the second floor steel scrap district. Because the flue gas does not pass through the secondary combustion section in the furnace at this time, a secondary combustion chamber 13 is arranged after the refractory valve enters the upper annular flue 9-2, unburned gas is combusted in the secondary combustion chamber 13 before entering the upper annular flue 9-2, the peroxide coefficient is controlled, and oxidation of scrap steel is avoided.
The injection amount of the combustion-supporting gas of the secondary combustion section is controlled by the concentration of carbon monoxide at the top of the furnace, the carbon monoxide is injected until the concentration of the carbon monoxide reaches the level not exceeding the local environmental protection emission standard, and the carbon monoxide detector is arranged at the top of the scrap steel preheating shaft furnace 2 to obtain the concentration of the carbon monoxide at the top of the furnace at any time.
The height of each layer of scrap preheating section of the vertical section of the scrap preheating shaft furnace 2 is designed according to the addition amount of each scrap according to the process requirements, the change of the scrap density and the bulk density change caused by blanking are fully considered, the condition that equipment cannot normally operate due to expanded materials is avoided, and the scrap is relatively stable.
And the oblique blanking channel is provided with a refractory material sealing and blocking valve 7 to prevent the oblique blanking channel from being mixed with gas and prevent the radiant heat of the electric arc furnace 1 from causing high-temperature damage to equipment at the bottom of the scrap steel preheating shaft furnace 2.
The furnace top of the scrap steel preheating shaft furnace 2 is provided with a charging isostatic pressing chamber 14, the side wall of the furnace top is connected with a shaft furnace smoke exhaust pipeline, the shaft furnace smoke exhaust pipeline is sequentially provided with a pipeline reactor 15, a dust remover 16, an induced draft fan 17 and a chimney 18, the inlet of the induced draft fan is provided with a deflation valve 19, and the chimney 18 is designed to have a reasonable height according to the local environmental protection requirement.
A gap is arranged between the oblique scrap steel feeding channel and the furnace body of the electric arc furnace 1 and is sealed by a sealing system 6; the utility model discloses a tilting operation, including the electric arc furnace 1 furnace body, the pipe of discharging fume 3, the electric arc furnace 1 furnace body between be equipped with the clearance to seal through hydraulic seal ring 11, so that the electric arc furnace steel-tapping, rotation operations such as slag tap, when the electric arc furnace need tilt, open closed system, the electric arc furnace can freely realize the operation of tilting.
A moving gap is reserved between an inclined feeding channel of the scrap steel preheating shaft furnace 2 and a charging opening of the electric arc furnace 1 and is connected in a sealing mode through a sealing system 6, and a refractory material blocking valve 7 is arranged in the middle of the inclined feeding channel.
When the device is designed into a three-layer preheating section, a lower annular flue 9-1 is arranged at a position of 300-600mm above a rotary flap valve 8 and is connected with the interior of the shaft furnace through a branch gas pipe, so that firstly, high-temperature flue gas is prevented from causing high-temperature damage to furnace bottom equipment, secondly, the furnace bottom equipment is prevented from being bonded due to the fact that a small amount of scrap steel is melted, and the specific distance is determined according to the temperature of the flue gas, the amount of the flue gas, the smelting period and the type of the scrap steel. A first layer of manipulator 10-1 is arranged at the position 200-300mm above the highest position of the first layer of scrap steel; an upper annular flue 9-2 is arranged on the first layer of manipulator 10-1 at 200-400mm, and is connected with the interior of the shaft furnace by a bronchus; calculating the top height of the second layer of scrap steel according to the selected scrap steel bulk density and the furnace sectional area, reserving a certain safety distance, arranging a second layer of manipulator 10-2, and supporting the third layer of scrap steel; according to the height of the third layer of scrap steel, considering the requirement of a discharging mechanism, a charging isostatic pressing chamber 14 is arranged at the top of the scrap steel preheating shaft furnace 2; the charging isostatic chamber 14 is provided with an upper closing plate and a lower closing plate.
The steelmaking process of the electric arc furnace with the one-time combustion auxiliary heating adopts the equipment, and comprises the following steps:
(1) obtaining high-temperature flue gas during the operation of the electric arc furnace, introducing a layer of scrap steel preheating section-N-1 layer of scrap steel preheating section in parallel through a smoke exhaust pipe 3, adding scrap steel into different preheating sections in a scrap steel preheating shaft furnace 2 in batches, continuously heating the layer of scrap steel by the lower layer of flue gas upwards, finally reducing the temperature of the flue gas to 80-150 ℃ after the flue gas exchanges heat with the scrap steel, discharging the flue gas from a smoke exhaust port of the shaft furnace, and enabling power to come from a rear induced draft fan.
(2) After the whole equipment operates stably, strong reducing gas is blown into the electric arc furnace through the nozzle 5 at the upper part of the electric arc furnace, nitrogen oxides generated by the electric arc and the combustion of the lower oxygen combustion gun are reduced and removed, and the nitrogen oxides and the surplus oxygen of the lower oxygen combustion gun are combusted, so that the oxygen oxidability is reduced, and the burning loss of scrap steel is reduced. The unreacted reducing gas is burned in the secondary combustion section or chamber.
(3) When the heating temperature of the first layer of scrap steel reaches a soft melting point, the compression density of the bottom scrap steel is increased, the system resistance is rapidly increased, when the design limit value is reached, a high-temperature resistant refractory valve 12 in front of a secondary combustion chamber 13 is started, most of flue gas can directly enter an upper annular flue to directly heat the second layer and the upper layer of scrap steel, a combustion-supporting air system of the secondary combustion chamber 13 is started when the valve 12 is started, the combustion-supporting air system is shared with a combustion-supporting air system of a secondary combustion section in the shaft furnace, a switching valve is arranged, and the combustion-supporting air quantity is controlled by the carbon monoxide concentration detected by a flue gas detection system at a smoke outlet of the shaft furnace;
(4) before the electric arc furnace taps steel, stopping oxygen combustion gun and strong reduction gas jetting, stopping the draught fan, or starting to the lowest gear, and setting an air inlet valve in front of the draught fan, so as to avoid the oxidation of scrap steel caused by the air entering the scrap steel preheating shaft furnace system. Frequent adjustment of the frequency conversion system is avoided. Opening a sealing system between the scrap steel blanking channel and the flue gas channel and between the scrap steel blanking channel and the electric arc furnace body, and tilting the furnace body to discharge steel;
(5) after steel is discharged, a sealing system 6 between the scrap steel discharging channel and the flue gas channel and between the scrap steel discharging channel and the electric arc furnace body is closed, a refractory material sealing plate of the scrap steel discharging channel is opened, a rotary flap valve at the bottom of the scrap steel preheating shaft furnace 2 is pulled out for cutting, a rotary flap valve 8 is started, the scrap steel falls into the electric arc furnace 1, and steel is left for reducing the impact of the scrap steel on the bottom of the electric arc furnace;
(6) after adding the scrap steel, closing the rotary flap valve 8, inserting a bolt, recovering the refractory sealing barrier valve 7 to a protection state, withdrawing the first layer of manipulator, placing the second layer of scrap steel on the furnace bottom, recovering the first layer of manipulator to a supporting state, withdrawing the second layer of manipulator, placing the third layer of scrap steel on the first layer of manipulator, and recovering the second layer of manipulator to the supporting state; the whole process is completed.
In the step (1), nitrogen oxides in the flue gas of the electric arc furnace are reduced into nitrogen gas, and the nitrogen gas is removed.
In the step (1), the arc temperature of the electric arc furnace is extremely high, and nitrogen can be oxidized to generate nitrogen oxide in a high-temperature thermal environment due to air brought by raw materials and air entering the furnace because the furnace is not tightly sealed. Secondary combustion within the furnace also produces nitrogen oxides. The temperature fluctuation of the flue gas of the electric arc furnace is too large, so that a proper section is difficult to find for conventional flue gas denitration. Therefore, the flue gas denitration is not carried out on the current electric arc furnace flue gas. In order to solve the problem, a strong reducing agent reduction method is adopted for denitration, and strong reducing gas is sprayed into the electric arc furnace through a strong reducing gas nozzle 5 at the upper part in the electric arc furnace. Such as natural gas, coke oven gas, etc. Under high temperature environment, nitrogen oxides are rapidly reduced into nitrogen by gas with strong reducibility and removed.
In the step (1), specifically, the charging isostatic pressing chamber at the top of the scrap preheating shaft furnace 2 is charged with scrap, the upper sealing plate is opened when the charging isostatic pressing chamber is charged with the scrap, the upper sealing plate is closed after the scrap is charged, and the lower sealing plate is opened when the scrap is charged into the scrap preheating shaft furnace 2, so that the pressure of the top of the furnace is not released.
In the step (1), when the second layer of manipulator returns to the supporting state, the lower sealing plate of the isostatic pressing chamber is opened, after the scrap steel falls to the second layer of manipulator, the lower sealing plate returns to the sealing state, the upper sealing plate can be continuously opened, the material is fed into the isostatic pressing chamber, the upper sealing plate is closed after the scrap steel is added, and the furnace top sealing is strengthened.
In the step (2), the remained unburned reducing gas enters the shaft furnace, and oxidation of the steel scrap in the high-temperature area of the shaft furnace is avoided due to the existence of the excessive reducing gas. Selecting the temperature of the shaft furnace 550 and the 800 ℃ section, and blowing air into the shaft furnace for secondary combustion. The gas has combustion condition at the temperature, and the scrap steel is not easy to oxidize.
In the step (2), an oxygen coal gun or an oxygen combustion gun 4 of the electric arc furnace selects fuel according to the advantages of local resources, strong reducing gas is natural gas or coke oven gas, and the like, if the selected gas is natural gas or coke oven gas, the aim of controlling nitrogen oxide can be achieved by adjusting the oxygen combustion ratio of combustion in the furnace, so that a strong reducing gas nozzle 5 can be omitted; when coal is selected as fuel, low sulfur, low phosphorus and low ash content are selected as far as possible, and the influence of the ash content on the alkalinity and harmful components of the slag is considered when the electric arc furnace is used for slagging.
In the step (2), because the primary combustion is added, the sulfur of the flue gas is increased and needs to be treated, and because the waste steel is coated with paint and oil-like substances, harmful gases such as dioxin and benzopyrene are generated during preheating, a surface active adsorption material is sprayed into the pipeline reactor 15 for desulfurization and dioxin and benzopyrene removal; the dust collector 16 is used for collecting surface active substances injected by the pipeline reactor and dust of the shaft furnace system; the draught fan 17 is used for providing operation power for the whole system, and a proper fan is selected according to the resistance and the smoke volume of the whole system. The control information of the induced draft intensity of the fan comes from a pressure sensor of the electric arc furnace and controls micro negative pressure or micro positive pressure in the furnace. Controlling according to the smelting process; the treated flue gas is discharged through a chimney 18 after reaching the standard, and the surface active adsorption material selects activated carbon powder.
And (3) in the step (2), an induced draft fan is selected and designed according to the smoke resistance and the smoke volume of the whole system, and a variable frequency motor is selected as the motor of the induced draft fan. The frequency conversion fan is controlled to keep the micro negative pressure point of the electric arc furnace mouth, because the excess gas exists in the furnace, the atmosphere in the furnace can not be damaged by little air, and thus, the furnace gas leakage can be avoided.
And (2) adopting a secondary combustion process, namely adopting low oxygen-fuel ratio combustion in the hearth to ensure that furnace gas is reductive, reducing the high-temperature burning loss of the preheated scrap steel, if the fuel is solid carbon fuel, additionally blowing partial strong reductive gas at the upper part of the electric arc furnace to reduce nitrogen oxides in the flue gas, and blowing secondary combustion in an empty material section between the top of the first layer of scrap steel and the second layer of scrap steel by using unburned carbon monoxide and additionally blown strong reductive gas. The secondary combustion section is provided with a normally-burning small oxygen combustion gun for ignition. Because the temperature is lower, the burning loss of the scrap steel is less when the scrap steel is subjected to secondary combustion, and the combustion type nitrogen oxides are not generated basically when the scrap steel is combusted at the temperature.
In the step (2), the steel scrap is heated in a segmented mode through the matching of the refractory material blocking valve 7 and the secondary combustion chamber 13, so that the overall temperature of the steel scrap is increased. Because the heating temperature of the bottom scrap steel cannot be too high, otherwise the scrap steel can be softened and adhered to influence the air permeability of the shaft furnace and be limited by the temperature rise of the lower part, and the temperature of the upper scrap steel cannot be too high. The problem that the smoke exhaust system cannot work due to the fact that system resistance is increased because preheating time of scrap steel is prolonged when smelting is abnormal can also be solved. According to the principle, the method of adopting each layer of small-batch scrap steel and a plurality of secondary combustion chambers can be adopted, and the integral preheating temperature of the scrap steel is improved.
In the step (2), a secondary combustion process is adopted, reducing atmosphere is formed below a secondary combustion section, and if the preheated scrap steel is a crushed material with high zinc content, part of flue gas is led out to be recycled as zinc before the secondary combustion.
In the step (2), a secondary combustion process is adopted, the flue gas before the secondary combustion section is in a reducing atmosphere, nitrogen oxides generated by high temperature of electric arcs in the furnace and nitrogen oxides generated during combustion can be reduced into nitrogen, the secondary combustion temperature of the upper part is lower, and nitrogen oxides cannot be generated any more, so that the nitrogen oxides of the flue gas can be controlled to be very low. The difficult problem that the oxygen of the electric arc furnace can not be denitrated is solved.
In the step (2), the whole equipment operates initially, and because the temperature of the whole system is low, the temperature of the secondary combustion section is low, secondary combustion cannot be realized, strong reducing gas is not injected at the moment, the oxygen proportion can be properly increased, and the concentration of carbon monoxide in the discharged flue gas is ensured to reach the standard. Because the temperature of the scrap steel is low at this time, the burning loss of the scrap steel is not serious. The gas escape is avoided; a normally-burning small oxygen burning gun is arranged in the secondary combustion section to play a role in igniting and supporting combustion; the injection amount of combustion-supporting air for secondary combustion is controlled by the concentration of carbon monoxide detected by a smoke detection system at a smoke outlet of the shaft furnace; and starting to blow strong reducing gas when the equipment enters normal operation.
In the step (4), when the electric arc furnace stops coal injection and steel tapping, in order to prevent the scrap preheating system from sucking air, the rotating speed of the variable frequency fan is reduced to be very low or the induced air is stopped, the variable frequency fan is not suitable for frequent stopping and starting, and in order to facilitate the regulation and control of the induced air pressure of the shaft furnace, an air release valve 19 is arranged on a pipeline between the dust remover 16 and the induced draft fan 17, so that the frequent starting of the variable frequency fan is avoided.
In the process, the first layer of mechanical arm is air-cooled. Because the gas quantity of the secondary combustion is small, the general temperature is not too high, the air cooling can be satisfied, and the water cooling is preferably not needed;
the charging system of the scrap steel considers the problem of material leakage of the supporting of a manipulator and also considers the problem of air permeability of the air inlet part of the annular flue, and broken materials and light and thin materials with poor air permeability are not required to be charged in the charging system.
The invention has the beneficial effects that:
the process disclosed by the invention solves the denitration problem through two-step combustion, reduces the burning loss of the scrap steel, obviously improves the integral charging temperature of the scrap steel by adding a secondary combustion heat source, solves the problems of system resistance surge and even system incapability caused by high preheating temperature of the scrap steel, comprehensively realizes the effects of emission reduction and cost reduction, reduces the burning loss of steel materials, and ensures that the flue gas emission reaches the standard.
Drawings
Fig. 1 is a schematic structural diagram of a steelmaking apparatus of a primary combustion auxiliary heating electric arc furnace according to embodiment 1 of the present invention, wherein:
1-electric arc furnace, 2-scrap steel preheating square shaft furnace, 3-connecting flue, 4-oxygen coal gun, 5-strong reducing gas nozzle, 6-hydraulic sealing system, 7-refractory material sealing and separating valve, 8-split rotating plate valve, 9-1 lower annular flue, 9-2 upper annular flue, 10-1 first layer mechanical arm, 10-2 second layer mechanical arm, 11-hydraulic sealing ring, 12-refractory material valve, 13-secondary combustion chamber, 14-charging isostatic pressing chamber, 15-pipeline reactor, 16-dust remover 16, 17-induced draft fan, 18-chimney and 19-air release valve.
Detailed Description
Example 1
A short-flow steel plant with 75 tons of ultrahigh-power electric arc furnaces is provided with a ladle oxygen combustion gun for heating scrap steel in order to reduce cost and improve capacity. The heat efficiency is less than 40 percent, the burning loss of the scrap steel is more than 11 percent, the flue gas is only dedusted, and the sulfur, the nitrate and the dioxin all exceed the standard. The environmental protection can not reach the standard, and is stopped by local environmental protection departments. Because no scrap steel is heated, the smelting period can not meet the requirements of continuous casting procedures, and the phenomenon of casting break frequently occurs, so that the cost is increased. In order to solve the problem of scrap steel preheating, the technology and equipment are adopted.
The steelmaking equipment of the primary combustion auxiliary heating electric arc furnace has the structural schematic diagram as shown in figure 1: four oxygen coal guns 4 and two natural gas nozzles 5 are arranged on the wall of a 75-ton electric arc furnace 1, a scrap steel preheating square shaft furnace 2 is built above the side of the electric arc furnace, the side length of a refractory material in the furnace is 2 meters, and the minimum bulk density of the scrap steel is designed according to 2.0 tons/cubic meter. A 2-meter square opening is formed in the furnace cover of the electric arc furnace and used for feeding scrap steel; the scrap steel in the shaft furnace is divided into three layers, two mechanical arms 10-1 and 10-2 are arranged, and each layer of scrap steel is 35-40 tons in advance. Adding scrap steel in two times during smelting in each furnace;
the bottom of the shaft furnace is provided with a rotary flap valve 8, the rotary flap valve 8 is provided with a locking bolt, a first layer of manipulator 10-1 is arranged at a position 6 meters away from the rotary flap valve 8 arranged at the bottom of the shaft furnace, a second layer of manipulator 10-2 is 5.5 meters away from the first layer of manipulator 10-1, and the top of the scrap preheating shaft furnace 2 and the second layer of manipulator 10-2 are 6 meters;
the bottom of the shaft furnace is connected with a scrap steel charging hole of an electric arc furnace by an inclined slideway, a certain gap is left between a sealing seat arranged at the scrap steel charging hole of the electric arc furnace and the inclined slideway of the scrap steel, the electric arc furnace is sealed by a hydraulic sealing system 6, and when the electric arc furnace tilts to tap and slag is discharged, a hydraulic sealing plate 6 is automatically opened; a refractory material sealing separation valve 7 is arranged on the inclined slideway to separate the radiant heat of the electric arc furnace, prevent high-temperature flue gas from leaking and protect bottom equipment of the shaft furnace;
taking a three-section type preheating channel as an example, a lower annular flue 9-1 and an upper annular flue 9-2 are respectively arranged at the upper parts of the scrap steel preheating shaft furnace 2, which are 500mm and 6300mm away from the furnace bottom, and the upper annular flue and the lower annular flue are connected with branch gas pipes arranged at the periphery in the shaft furnace; the lower annular flue and the upper annular flue are connected with the exhaust port of the electric arc furnace by a connecting flue.
The lower annular flue 9-1 and the upper annular flue 9-2 are connected with a connecting flue 3 for an exhaust port of an electric arc furnace, a secondary combustion chamber 13 is arranged before the connecting flue 3 enters the upper annular flue 9-2, a refractory material valve 12 is arranged on the connecting flue 3 in front of the secondary combustion chamber 13, a secondary combustion section in the furnace is arranged between a first layer of waste steel material top and a first layer of mechanical arm, 3 auxiliary gas nozzles are arranged on each surface of the furnace wall, combustion-supporting gas is blown in a secondary combustion section to burn unburned gas, and the combustion-supporting gas is selected to be compressed air for convenient adjustment, and the amount of the injected combustion-supporting gas is adjusted according to the concentration of carbon monoxide detected by a carbon monoxide gas detector at a smoke outlet of the furnace top. The command system of the high-temperature resistant material valve 12 is limited by system resistance, the high-temperature resistant material valve 12 is connected with the command system, the command system can detect the pressure of equipment, when the detected negative pressure value reaches a set value, the command system automatically opens the high-temperature resistant material valve 12, the combustion-supporting gas system of the secondary combustion chamber 13 is shared with the combustion-supporting gas system of the secondary combustion section in the furnace, when the high-temperature resistant material valve 12 is opened, the combustion-supporting gas system is automatically switched to the secondary combustion chamber 13 for supporting combustion, and simultaneously, the combustion-supporting gas amount is automatically adjusted and sprayed according to the carbon monoxide concentration value of the smoke detection system, so that the carbon monoxide concentration is reduced to the local environment-friendly emission standard.
The electric arc furnace exhaust port is provided with a connecting sealing seat, a certain gap is reserved between the connecting flue 3 and the electric arc furnace exhaust port connecting sealing seat, the hydraulic sealing ring 11 is used for sealing, and the hydraulic sealing ring 11 can be automatically opened when the electric arc furnace tilts to tap and slag is discharged;
two split rotary plate valves 8 are arranged at the bottom of the shaft furnace, the rotary shafts are arranged at two sides, when the rotary plate is in a state of sealing and bearing scrap steel, the middle parts of the rotary plate valves are respectively provided with locking bolts of the two rotary plate valves, when the scrap steel is unloaded, the bolts are firstly pulled out, the rotary plate valve rotating system is started to unload the scrap steel, and the rotary plate valves are screwed back to the sealing state after the scrap steel is unloaded, and the bolts are inserted.
The top of the shaft furnace is provided with an isostatic pressing sealing feeding system. The isostatic pressing sealing feeding system is provided with an upper sealing plate and a lower sealing plate, the upper sealing plate and the lower sealing plate are in a sealing state during the non-working period of the feeding system, the upper sealing plate is opened when scrap steel is added into a scrap steel groove, the upper sealing plate is closed after the scrap steel is added, the lower sealing plate is opened when the scrap steel is added into the shaft furnace, and the lower sealing plate is closed after the scrap steel is discharged. Therefore, the problem that the normal smoke flow of the system is influenced due to the fact that a large amount of wild wind enters the system due to the pressure relief of the system can be avoided.
And a vent valve 19 is arranged on a pipeline between the dust remover 16 and the induced draft fan 17, and the vent valve is started to adjust the state when the frequency modulation fan runs to a low position. The regulation control system signal is from the electric arc furnace pressure sensor.
The main fuel selects 6500 kilocalorie of anthracite with calorific value, 40 kilograms of coal injection per ton steel, 10 cubic meters of natural gas per ton steel, 100 kilowatt-hour of electricity per ton steel and 95 cubic meters of oxygen per ton steel. Before transformation, 550 degrees per ton of steel is consumed by one ton of steel, 40 cubic meters per ton of steel is consumed by oxygen, 15 kilograms per ton of steel is consumed by coal powder, and 550 kilowatt-hours per ton of steel is consumed by electricity.
The metal yield is as follows: 89% before modification and 97% after modification, and is improved by 8%.
Removal rate of nitrogen oxides: 350mg/Nm before modification330mg/Nm after modification3。
The coal cost is calculated according to 800 yuan/ton steel, the electricity price is calculated according to 0.6 yuan/kilowatt hour, the oxygen is calculated according to 0.5 yuan/cubic meter, the natural gas is calculated according to 2.8 yuan/cubic meter, the steel and iron loss is calculated according to 2500 yuan/ton steel, the fuel cost is saved for 190 yuan/ton steel per ton steel, the steel and iron material is saved, and the cost is reduced to 200 yuan/ton steel. The effect of reducing cost is obvious.
The smelting period is shortened by 10 minutes after the transformation, and the continuous casting rhythm can be completely met. The smoke emission completely meets the environmental protection requirement. The emission of carbon dioxide per ton of steel is reduced by about 300 kg/ton of steel, and the emission is reduced by about 60%.
Claims (10)
1. The utility model provides a burning boosting electric arc furnace steelmaking equipment, its characterized in that preheats the shaft furnace including electric arc furnace and the scrap steel that are connected, electric arc furnace top be equipped with the pipe of discharging fume, the pipe of discharging fume preheat the shaft furnace with the scrap steel and be connected, the scrap steel preheat the shaft furnace stove bottom and be equipped with rotatory flap valve, wherein:
the vertical section channel of the scrap steel preheating shaft furnace is an N-section type preheating channel, and specifically comprises a first-layer scrap steel preheating section, a second-layer scrap steel preheating section, … and an N-layer scrap steel preheating section from bottom to top, wherein N is 2-4;
the vertical section channel of the scrap steel preheating shaft furnace is sequentially provided with a first layer of mechanical arm, a second layer of mechanical arm, … and an N-1 layer of mechanical arm from bottom to top, a first layer of scrap steel preheating section is formed between the rotary flap valve and the first layer of mechanical arm, a second layer of scrap steel preheating section is formed between the second layer of mechanical arm and the first layer of mechanical arm, …, and N layers of scrap steel preheating sections are formed above the N-1 layer of mechanical arm;
one layer of scrap steel preheating section, two layers of scrap steel preheating sections and … in the shaft furnace section N-section type preheating channel of the scrap steel preheating shaft furnace are respectively provided with an annular flue at the bottom of the side wall of the N-1 layer of scrap steel preheating section, one end of the annular flue is connected with the scrap steel preheating shaft furnace through a branch gas pipe, and the other end of the annular flue is connected with a smoke exhaust pipe.
2. The primary combustion auxiliary heating electric arc furnace steelmaking apparatus of claim 1, wherein:
a plurality of strong reducing gas nozzles are uniformly arranged axially above the furnace wall of the electric arc furnace at intervals, and a plurality of oxygen burners are uniformly arranged axially below the furnace wall at intervals;
the scrap steel preheating shaft furnace comprises an upper vertical channel and a bottom inclined blanking channel, and is arranged obliquely above the electric arc furnace and connected with the electric arc furnace through the inclined blanking channel;
the rotary flap valve is provided with a locking bolt in a matching way.
3. The primary combustion auxiliary heating electric arc furnace steelmaking apparatus of claim 1, wherein:
a high-temperature resistant and material-resistant valve is arranged on a smoke exhaust pipe connected with an annular flue at the bottom of the side wall of the preheating section of the layer 2 of scrap steel, and a secondary combustion chamber is arranged between the high-temperature resistant and material-resistant valve and the annular flue;
and a secondary combustion section is arranged between the first layer of mechanical arm and the first layer of scrap steel material top, and a combustion-supporting gas injection system is arranged in a matching manner in the secondary combustion section.
4. The steelmaking apparatus as claimed in claim 1, in which combustion supporting gas nozzles and small oxygen burners are provided between the top of the first layer of scrap and the bottom of the second layer of scrap, the oxygen burners being located away from the robot.
5. The primary combustion auxiliary heating electric arc furnace steelmaking equipment as claimed in claim 1, wherein the inclined blanking channel is provided with a refractory material sealing separation valve, the top of the scrap steel preheating shaft furnace is provided with a charging isostatic pressing chamber, the side wall of the top of the furnace is connected with a shaft furnace smoke exhaust pipeline, the shaft furnace smoke exhaust pipeline is sequentially provided with a pipeline reactor, a dust remover, an induced draft fan and a chimney, the inlet of the induced draft fan is provided with a deflation valve, and the chimney is designed to have a reasonable height according to local environmental protection requirements.
6. The primary combustion auxiliary heating electric arc furnace steelmaking apparatus of claim 1, wherein:
a gap is arranged between the oblique scrap steel feeding channel and the electric arc furnace body and is sealed by a sealing system; a gap is arranged between the smoke exhaust pipe and the electric arc furnace body and is sealed by a hydraulic sealing ring;
a moving gap is reserved between an inclined blanking channel of the scrap steel preheating shaft furnace and a charging opening of an electric arc furnace, the inclined blanking channel is connected in a sealing mode through a sealing system, and a refractory material separation valve is arranged in the middle of the inclined blanking channel.
7. Method for primary combustion-assisted heating of electric arc furnace steelmaking, characterized in that the use of the apparatus according to any of claims 1 to 6 comprises the following steps:
(1) obtaining high-temperature flue gas in the operation process of the electric arc furnace, introducing a layer of scrap steel preheating section-N-1 layer of scrap steel preheating section in parallel through a smoke exhaust pipe, adding scrap steel into different preheating sections in a scrap steel preheating shaft furnace in batches, continuously heating the layer of scrap steel by the lower layer of flue gas upwards, finally cooling the flue gas to 80-150 ℃ after heat exchange with the scrap steel, and discharging the flue gas from a smoke exhaust port of the shaft furnace;
(2) after the whole equipment operates stably, strong reducing gas is blown into the electric arc furnace from the upper part of the electric arc furnace to reduce and remove nitrogen oxides generated by the electric arc and the combustion of the lower oxygen combustion gun, and the nitrogen oxides and the surplus oxygen of the lower oxygen combustion gun are combusted, so that the oxygen oxidability is reduced, and the burning loss of scrap steel is reduced;
(3) when the heating temperature of the first layer of scrap steel reaches a soft melting point, the compression density of the bottom scrap steel is increased, when the system resistance reaches a design limit value, a high-temperature resistant refractory valve in front of a secondary combustion chamber is started, most of flue gas directly enters an upper annular flue, and the second layer of scrap steel and the upper layer of scrap steel are directly heated;
(4) before the electric arc furnace discharges steel, stopping the oxygen combustion gun and the strong reduction gas injection, stopping or starting the draught fan to the lowest gear, avoiding the scrap steel preheating shaft furnace system from entering air to cause scrap steel oxidation, opening a sealing system between a scrap steel blanking channel and a flue gas channel and the electric arc furnace body, and tilting the furnace body to discharge steel;
(5) after steel is discharged, a sealing system between the scrap steel discharging channel and the flue gas channel and the electric arc furnace body is closed, a refractory sealing plate of the scrap steel discharging channel is opened, a rotary flap valve at the bottom of the scrap steel preheating shaft furnace is pulled out for cutting, the rotary flap valve is started, the scrap steel falls into the electric arc furnace 1, steel retaining operation is carried out, and the impact of the scrap steel on the bottom of the furnace is reduced;
(6) after adding the scrap steel, closing the rotary flap valve, recovering the refractory sealing barrier valve to a protection state, withdrawing the first layer of manipulator, placing the second layer of scrap steel on the furnace bottom, recovering the first layer of manipulator to a supporting state, withdrawing the second layer of manipulator, placing the third layer of scrap steel on the first layer of manipulator, recovering the second layer of manipulator to the supporting state, and sequentially recovering the manipulators to the supporting state; the whole process is completed.
8. The steelmaking method using an electric arc furnace as claimed in claim 7, wherein in the step (1), the nitrogen oxides in the flue gas of the electric arc furnace are reduced to nitrogen gas and removed.
9. The steelmaking method as claimed in claim 7, wherein in the step (2), the remaining unburnt reducing gas is introduced into the shaft furnace, oxidation of steel scrap in the high temperature region of the shaft furnace is avoided due to the existence of the surplus reducing gas, and air is blown into the zone at the temperature of 550 ℃ and 800 ℃ of the shaft furnace for secondary combustion to ensure that the unburnt reducing gas is burnt out and the steel scrap is not oxidized.
10. The steelmaking method of the electric arc furnace with the primary combustion auxiliary heating as claimed in claim 7, wherein in the step (3), a combustion-supporting air system of the secondary combustion chamber is started at the same time when the high-temperature resistant and material resistant valve is started, the combustion-supporting air system is shared with a combustion-supporting air system of the secondary combustion section in the shaft furnace, a switching valve is arranged, and the combustion-supporting air quantity is controlled by the carbon monoxide concentration detected by a flue gas detection system at a smoke outlet of the shaft furnace at the same time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111098608.9A CN113699308B (en) | 2021-09-18 | 2021-09-18 | Primary combustion auxiliary heating electric arc furnace steelmaking equipment and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111098608.9A CN113699308B (en) | 2021-09-18 | 2021-09-18 | Primary combustion auxiliary heating electric arc furnace steelmaking equipment and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113699308A true CN113699308A (en) | 2021-11-26 |
| CN113699308B CN113699308B (en) | 2024-05-03 |
Family
ID=78661159
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111098608.9A Active CN113699308B (en) | 2021-09-18 | 2021-09-18 | Primary combustion auxiliary heating electric arc furnace steelmaking equipment and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113699308B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114692434A (en) * | 2022-06-02 | 2022-07-01 | 河北科技大学 | Grading method and device for preheating scrap steel, electronic equipment and storage medium |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2405174Y (en) * | 2000-01-07 | 2000-11-08 | 中国船舶重工集团公司第七研究院第七○三研究所 | Equipment for preheating waste steel using flue gas from vertical kiln-electric furnace combination |
| DE102008060774A1 (en) * | 2008-12-05 | 2010-07-15 | Raile, Wiktor, Dipl.-Ing. | Scrap preheating process in steel production plants, comprises guiding furnace exhaust gas from melting unit into preheater, which flows through scrap column and preheats the furnace exhaust gas by guidable heat of the furnace exhaust gas |
| CN109880959A (en) * | 2019-04-04 | 2019-06-14 | 石家庄巨力科技股份有限公司 | A method of improving converter steel scrap adding proportion |
| CN111485060A (en) * | 2020-05-27 | 2020-08-04 | 沈阳东大山汇环境科技有限公司 | Self-generating coal gas circulation non-tail gas emission smelting steel scrap system and steel-making method |
| CN111518986A (en) * | 2020-05-27 | 2020-08-11 | 沈阳东大山汇环境科技有限公司 | System for smelting scrap steel by utilizing primary combustion heat energy and steelmaking method thereof |
| CN111621612A (en) * | 2020-06-23 | 2020-09-04 | 沈阳东大山汇环境科技有限公司 | Converter tail gas waste heat dry distillation coal cracking gas preheating steelmaking system and steelmaking method |
| CN216107053U (en) * | 2021-09-18 | 2022-03-22 | 沈阳东大山汇环境科技有限公司 | One-time combustion auxiliary heating electric arc furnace steelmaking equipment |
-
2021
- 2021-09-18 CN CN202111098608.9A patent/CN113699308B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2405174Y (en) * | 2000-01-07 | 2000-11-08 | 中国船舶重工集团公司第七研究院第七○三研究所 | Equipment for preheating waste steel using flue gas from vertical kiln-electric furnace combination |
| DE102008060774A1 (en) * | 2008-12-05 | 2010-07-15 | Raile, Wiktor, Dipl.-Ing. | Scrap preheating process in steel production plants, comprises guiding furnace exhaust gas from melting unit into preheater, which flows through scrap column and preheats the furnace exhaust gas by guidable heat of the furnace exhaust gas |
| CN109880959A (en) * | 2019-04-04 | 2019-06-14 | 石家庄巨力科技股份有限公司 | A method of improving converter steel scrap adding proportion |
| CN111485060A (en) * | 2020-05-27 | 2020-08-04 | 沈阳东大山汇环境科技有限公司 | Self-generating coal gas circulation non-tail gas emission smelting steel scrap system and steel-making method |
| CN111518986A (en) * | 2020-05-27 | 2020-08-11 | 沈阳东大山汇环境科技有限公司 | System for smelting scrap steel by utilizing primary combustion heat energy and steelmaking method thereof |
| CN111621612A (en) * | 2020-06-23 | 2020-09-04 | 沈阳东大山汇环境科技有限公司 | Converter tail gas waste heat dry distillation coal cracking gas preheating steelmaking system and steelmaking method |
| CN216107053U (en) * | 2021-09-18 | 2022-03-22 | 沈阳东大山汇环境科技有限公司 | One-time combustion auxiliary heating electric arc furnace steelmaking equipment |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114692434A (en) * | 2022-06-02 | 2022-07-01 | 河北科技大学 | Grading method and device for preheating scrap steel, electronic equipment and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113699308B (en) | 2024-05-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111518986B (en) | Steelmaking method of scrap steel smelting system by utilizing primary combustion heat energy | |
| CN111621612B (en) | Converter tail gas waste heat carbonization coal pyrolysis coal gas preheating steelmaking system and steelmaking method | |
| CN101413041B (en) | Coal-based direct reduction iron rotary hearth furnace and combustion method thereof | |
| CN215856209U (en) | External combustion type scrap steel preheating shaft furnace | |
| CN216107053U (en) | One-time combustion auxiliary heating electric arc furnace steelmaking equipment | |
| CN113699308B (en) | Primary combustion auxiliary heating electric arc furnace steelmaking equipment and method | |
| WO2018014148A1 (en) | Multistage roasting-smelting method and equipment for reduction ironmaking | |
| CN212713622U (en) | System for smelting scrap steel by utilizing once-combustion heat energy | |
| CN111250510B (en) | Flying ash melting treatment device and flying ash melting treatment method operating in sections | |
| CN108800926A (en) | Regenerative gas fire coal scrap melting stove | |
| CN218561557U (en) | Device for extracting heavy metal from hazardous waste through high-temperature melting and vitrification | |
| CN113652521A (en) | External combustion type scrap steel preheating shaft furnace and preheating method thereof | |
| CN212713623U (en) | Self-generating coal gas circulation non-tail gas emission smelting steel scrap system | |
| CN111485060B (en) | Self-generating gas circulation no-tail gas emission steel scrap smelting system and steel smelting method | |
| CN111074033B (en) | Method for directly reducing materials by using rotary hearth furnace | |
| CN203810892U (en) | Coal-oxygen blowing melting separation shaft furnace | |
| AU722145B2 (en) | The production of hot metal by the melting down of scrap as an iron source. | |
| CN215799327U (en) | Coal dry distillation and scrap steel preheating composite equipment | |
| CN212870719U (en) | Scrap steel melting furnace device with oxygen combustion gun as heat source | |
| CN205888057U (en) | Exempt from roast package ware device of switching -over from heat accumulation | |
| CN219572692U (en) | Continuous baking and adding device for converter steelmaking crushed materials | |
| CN113106181B (en) | Pure oxygen two-stage preheating reduction ironmaking equipment | |
| CN113137864B (en) | Alloy raw material preheating device and method | |
| CN115164202B (en) | Multiphase coupling organic/heavy solid-containing waste cooperative treatment process, system and control method | |
| CN113667502A (en) | Coal dry distillation and scrap steel preheating composite equipment and method |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |