CN112877485A - Method for smelting schreyerite in large blast furnace under low-thermal-state strength coke - Google Patents
Method for smelting schreyerite in large blast furnace under low-thermal-state strength coke Download PDFInfo
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- C21B5/00—Making pig-iron in the blast furnace
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Abstract
The invention discloses a method for smelting schreyerite in a large-scale blast furnace under coke with low thermal state strength, which uses the prior eight-steel self-produced sinter ore with alkalinity R = 1.8; sintering ore: mongolian pelletizing: vanadium-titanium pellet = 75%: 17%: 8 percent; adjusting blast furnace operating parameters: coke load O/C: 4.142, oxygen enrichment is maintained at 15500 +/-100 m for carrying out the year/h, and the oxygen enrichment rate is as follows: 4.5% -5%, top temperature: 135 +/-5 ℃, wherein PT of molten iron is 1490-1510 ℃, and [ Si ]: 0.35-0.45, [ Ti ] < 0.20%, fuel ratio: 540-560 kg/t; the ash content of the coke is 11-13%, and M40 is more than or equal to 89.5%; the blast furnace inlet air temperature is 1150-1250 ℃, and the furnace top pressure is 210 kPa; the mass percentage of iron in the sintered ore and the vanadium-titanium pellet ore is adjusted to be more than 56.8 percent in the smelting process, the binary alkalinity is 1.08-1.12, the coke ratio is 440kg/t of minus one-year coke, the coal ratio is 120kg/t of minus one-year coke, and the blast temperature is adjusted to be more than 1150 ℃.
Description
Technical Field
The invention relates to a method for smelting schreyerite in a large-scale blast furnace under low-thermal-state strength coke.
Background
Blast furnace ironmaking production is the most important link in the metallurgical (steel) industry. Blast furnace iron-making smelting is a continuous production process for reducing iron ore into elementary pig iron. The solid raw materials of iron ore, coke and flux are fed into the blast furnace in batches according to a specified proportioning ratio by a furnace top charging device, the furnace throat charge level is kept at a certain height, the coke and the ore form an alternate layered structure in the furnace, and the ore material is gradually reduced, melted into iron and slag in the descending process, gathered in a furnace hearth and discharged from an iron notch and a slag notch at regular intervals. China has wide distribution of vanadium titano-magnetite, abundant reserves, and the reserves and the exploitation amount of the vanadium titano-magnetite at the third position of iron ore nationwide, the reserves are proved to be nearly billion tons, the prospect reserves are more than three billion tons, the reserves of the vanadium titano-magnetite in Xinjiang are abundant, the reserves are proved to be billion tons, eight steel companies meet the strategic requirements of regional markets for regional resources, and the development and utilization are acceleratedThe vanadium-titanium mineral resources in Xinjiang achieve the aim of comprehensively developing and utilizing vanadium-titanium-iron ore concentrates of more than 100 million tons/year, the overall competitiveness of the iron and steel major industry of eight-steel companies is enhanced, the eight-steel blast furnace continuously increases the smelting of vanadium-titanium ores, and the pig iron cost is reduced. By adopting schreyerite smelting, titanium (Ti) is easy to react with carbon (C) and nitrogen (N) in a hearth to generate titanium carbide (TiC) and titanium nitride (TiN), and the titanium carbide (TiC) and the titanium nitride (TiN) cannot be melted at the temperature in the hearth of more than 1400 ℃, and the melting temperatures of the titanium carbide (TiC) and the titanium nitride (TiN) are 2950 ℃ and 3150 ℃. Therefore, TiC and TiN are main sources of the incomplete separation of vanadium-titanium magnetite slag and iron in blast furnace smelting. TiO in slag2For a long time, 19-21%, production practices show that the titanium content in pig iron increases, the viscosity of the pig iron also increases in different degrees, so that the molten iron is seriously stuck to a tank, and a plurality of slag runner hanging holes are formed. Under smelting conditions in which the titanium-containing slag is in a reducing atmosphere and in the presence of hot coke, the viscosity of the titanium-containing slag increases with the increase of the reducing temperature or the extension of the reducing time, so that the slag becomes thick. Thickening of the slag can also lead to upset furnace conditions. The vanadium-titanium ore smelting has the characteristics of large iron slag per ton and small stable slag performance interval, so that the vanadium-titanium ore smelting needs to use higher strength, particularly coke with good thermal state strength, ensures that a material column has good air permeability and liquid permeability, shortens the retention time of titanium-containing iron slag in a blast furnace, smoothly drops to a hearth from a reflow zone, discharges the iron slag in time, reduces the reduction of titanium elements, reduces the content of titanium in iron, activates the hearth, improves the space coefficient of the hearth, and ensures smooth furnace conditions. The thermal reactivity of coke influences the strength of the coke after reaction in the blast furnace, restricts the action of the coke on a stock column framework in the blast furnace, further influences the air permeability and the smooth operation of the blast furnace, if the reactivity of the coke is too high, the thermal strength of the coke is reduced, more broken coke and coke powder are generated to accumulate, a dead stock column is blocked, the blast furnace is difficult to accept high air temperature and high air temperature, and the activity of a furnace hearth is reduced. The degree of deterioration of the coke in the lower portion of the blast furnace has a direct influence on the permeability of the whole blast furnace, and therefore, a higher resistance to the solution loss reaction of the coke is required to improve the CSR of the coke. According to production experience, the coke thermal strength condition of the vanadium-titanium ore smelted by the blast furnace is that CSR is more than or equal to 65 percent, and 2000-4000 m is specified in the design specification of the blast furnace in China3Coke CR for blast furnaceI is less than or equal to 25 percent, and CSR is more than or equal to 62-65 percent. In order to meet the requirements of production and cost, the eight-steel blast furnace further reduces the smelting cost, a large amount of non-coking coal in Xinjiang is added into the coke, and Shanxi coking coal is reduced or not added, so that the coking cost is reduced to the minimum, the pig iron cost is further reduced, and the CSR of the eight-steel coke is less than or equal to 29.8 percent. Therefore, the eight-steel blast furnace smelts schreyerite under the coke with low thermal state strength, and in order to ensure that the blast furnace activates a hearth, stably runs for a long time and reduces the cost of ironmaking production, the production process technology for smelting the vanadium-titanium magnetite needs to be further excavated and improved so as to meet the operation requirements of low consumption, high yield and low cost of the blast furnace.
Disclosure of Invention
In order to solve the technical problem that the large-scale blast furnace can not use the coke with low thermal state strength in the vanadium-titanium ore smelting process, the technical scheme of the invention is to adopt a method for smelting vanadium-titanium ore in the large-scale blast furnace under the coke with low thermal state strength, analyze the technical principle of the vanadium-titanium ore smelting process through scientific technical means, and adopt innovative operation concepts and blast furnace regulating means to ensure that the blast furnace carries out the vanadium-titanium ore smelting under the fuel condition of the coke with low thermal state strength.
The method for smelting vanadium-titanium ore in the large-scale blast furnace under the coke with low thermal state strength, which achieves the aim, comprises the following steps of 1, selecting a proper furnace burden ore blending structure:
(1) sintering ore: using the alkalinity R =1.8 of the existing eight-steel self-produced sinter;
(2) pellet ore: using vanadium-titanium pellets and Mongolian pellets, and adjusting the load of titanium in the furnace by increasing the proportion of the vanadium-titanium pellets;
(3) basic ore blending structure proportion: sintering ore: mongolian pelletizing: vanadium-titanium pellet = 75%: 17%: 8 percent; the specific components of the agglomerate, the vanadium-titanium pellet and the Mongolian pellet are shown in the following table:
TFe of total iron grade =56.7%, basicity of sinter =1.8, TiO2 load 21.4 Kg/t iron
2. Low hot strength coke index: the coking coal blending produced by the coke completely uses local coal, and the thermal state strength of the coke is 29.8 percent;
3. adjusting blast furnace operating parameters:
maintaining the indexes: coke load O/C: 4.142, oxygen enrichment is maintained at 15500 +/-100 m for carrying out the year/h, and the oxygen enrichment rate is as follows: 4.5% -5%, top temperature: 135 +/-5 ℃, wherein PT of molten iron is 1490-1510 ℃, and [ Si ]: 0.35-0.45, [ Ti ] < 0.20%, fuel ratio: 540-560 kg/t; the ash content of the coke is 11-13%, and M40 is more than or equal to 89.5%; the temperature of blast furnace inlet air is 1150-1250 ℃, and the oxygen-enriched amount accounts for 4-5% (v/v) of the inlet air amount; the furnace top pressure is 210 kPa; the mass percentage of iron in the sintered ore and the vanadium-titanium pellet ore is adjusted to be more than 56.8 percent in the smelting process, the binary alkalinity is 1.08-1.12, the coke ratio is 440kg/t of minus one-year coke, the coal ratio is 120kg/t of minus one-year coke, and the blast temperature is adjusted to be more than 1150 ℃.
The tapping frequency of the molten iron is more than 8 times/day and night. Because molten iron and slag of the schreyerite have the characteristics of 'waiting' and 'stopping' in a hearth, the tapping times are increased in the operation in front of the furnace, the slag iron is placed on duty, and the slag is discharged in time.
The invention develops and discusses the key point of the vanadium-titanium ore smelting of the eight-steel blast furnace under the fuel condition of the coke with low thermal state strength from the basic principle of the vanadium-titanium ore smelting. The schreyerite is thermally deformed and locally softened at the furnace waist, and a large amount of primary slagging is generated at the furnace belly part, Ti02The slag is reduced into low-valence oxides, TiC and TiN from the furnace bosh to reach the maximum content in a tuyere area, and is reduced to the content of final slag from a tuyere to an iron notch. Ti0 in high titanium slag2When not reduced, the melting temperature is low and the fluidity is good, and the melting temperature is increased with the generation and increase of suboxides. The TiC and TiN are not melted under the condition of a blast furnace, the melting point of the TiC is 3140 +/-90 ℃, the melting point of the TiN is 2950 +/-50 ℃, and the temperature is far higher than the highest temperature in the furnace, so that the TiC and TiN are suspended in slag as solid particles, and the slag becomes viscous. The more TiC and TiN, the more viscous and viscous, so that the fluidity is lost. In the temperature range of blast furnace, CO and H2Reducing TiO only to a small extent2To Ti203TiO can not be reduced any more, Ti, TiC and TiN can not be produced, but the liquid slag can be directly reduced by C at a sufficient temperature in the furnace bosh after being generated. The reaction to produce Ti (C, N) in the furnace belly involves:
slag- -coke reaction:
TiO2+2C=[Ti]+2C0，[Ti]entering the iron phase.
TiO2+3C=TiC+2C0
TiO2+3C +1/2N2=TiN+2CO
TiC and TiN generated by the reaction are dispersed in the slag phase in the form of Ti (C, N) solid solution.
Slag- -iron reaction:
TiO2+2[C]=TiC+2C0
TiO2+2[C]+1/2N2=TiN+2CO
TiC and TiN are wrapped around iron beads in a slag phase in a Ti (C, N) solid solution mode to form a Ti (C, N) thin shell.
The above reactions are collectively referred to as slag phase reactions, and under blast furnace smelting conditions, these reactions are mainly limited by thermodynamic and kinetic conditions. The key point of the smelting technology is that the furnace temperature is controlled mainly by controlling Ti in the iron phase]The content is calculated. Therefore, control [ Ti]The content correspondingly controls the generation amount of low-valence titanium oxide and Ti (C, N), thereby achieving the purpose of preventing slag from thickening. According to the sample data of the pig iron of the blast furnace, the following steps are displayed: containing [ Si ] in molten iron]The higher the amount, the more the slag contains low-valent titanium compounds and TiC and TiN. Based on the smelting principle of schreyerite, the difficulty of schreyerite smelting is theoretically recognized not to occur at the upper part of a blast furnace but to occur at the lower part of the blast furnace; the slag is thickened and infusible not because of easy solidification of molten iron; the slag and iron cannot be tapped due to the low temperature of the hearth as in the common ore (of course, the titanium slag with low hearth temperature can be condensed in the furnace). Therefore, schreyerite smelting must compromise two aspects: (1) inhibiting TiO2Is a fundamental measure; (2) promoting the reoxidation of low-valence titanium compounds of titanium and TiC and TiN to TiO2. It can be seen that the reduction and oxidation of titanium in a blast furnace is a blast furnace smeltingThe two are in an opposite and unified relationship. To deal with this relationship, on the one hand, TiO is controlled2Only a small amount of reduction is needed, and on the other hand, the excessive low-valence titanium oxide is oxidized into TiO2So that the contradiction is unified and the blast furnace smelting can be normally carried out. Practice has shown that reduction is dominant, since blast furnace smelting is a reduction process, and oxidation does not proceed in large quantities in blast furnaces. Therefore, the vanadium-titanium ore smelting is mainly to control TiO2The reduction of (2) is carried out while maintaining a constant oxygen potential in the furnace hearth.
Through the discussion of the schreyerite smelting, under the blast furnace smelting condition, the key of the smelting technology lies in controlling the furnace temperature, and controlling the furnace temperature controls [ Ti ] in the iron phase]And (4) content. According to the production experience, the coke thermal strength condition of the vanadium-titanium ore smelted by the blast furnace is that CSR is more than or equal to 65 percent, and the requirement of low silicon (Si) of the blast furnace can be met]≤0.2%、[Ti]Less than or equal to 0.2 percent of smelting and further concealing enough vanadium-titanium ore smelting to inhibit TiO2The eight-steel blast furnace is used for meeting the requirements of production and cost, the smelting cost is further reduced, a large amount of non-coking coal in the coke is added, the CSR of the eight-steel coke is less than or equal to 29.8 percent, and the low-silicon smelting [ Si]The control difficulty is larger than or equal to 0.15 percent.
The invention provides a method for smelting vanadium-titanium ore in a large blast furnace under coke with low thermal state strength, which can ensure that the titanium load of eight-steel coke reaches 20.4Kg/t iron under the coke performance index that the thermal state strength CSR is less than or equal to 29.8 percent, simultaneously improve the iron yield of the blast furnace and the percent of pass of pig iron, improve various technical and economic indexes of smelting vanadium-titanium ore in the blast furnace, ensure the stable and smooth operation of the blast furnace, low consumption and high yield.
Detailed Description
A method for smelting schreyerite in a large-scale blast furnace under low-thermal-state-strength coke comprises the following steps of 1, selecting a proper furnace burden ore-blending structure:
(1) sintering ore: using the alkalinity R =1.8 of the existing eight-steel self-produced sinter;
(2) pellet ore: using vanadium-titanium pellets and Mongolian pellets, and adjusting the load of titanium in the furnace by increasing the proportion of the vanadium-titanium pellets;
(3) basic ore blending structure proportion: (sinter: Mongolian pellets: vanadium-titanium pellets = 75%: 17%: 8%);
the specific components of the agglomerate, the vanadium-titanium pellet and the Mongolian pellet are shown in the following table:
TFe of total iron grade =56.7%, basicity of sinter =1.8, TiO2 load 21.4 Kg/t iron
2. Low hot strength coke index: the coking coal blending produced by the coke completely uses local coal, and the thermal state strength of the coke is 29.8 percent;
3. adjusting blast furnace operating parameters:
maintaining the indexes: coke load O/C: 4.142, oxygen enrichment is maintained at 15500 +/-100 m for carrying out the year/h, and the oxygen enrichment rate is as follows: 4.5% -5%, top temperature: 135 +/-5 ℃, wherein PT of molten iron is 1490-1510 ℃, and [ Si ]: 0.35-0.45, [ Ti ] < 0.20%, fuel ratio: 540-560 kg/t; the ash content of the coke is 11-13%, and M40 is more than or equal to 89.5%; the temperature of blast furnace inlet air is 1150-1250 ℃, and the oxygen-enriched amount accounts for 4-5% (v/v) of the inlet air amount; the furnace top pressure is 210 kPa; the mass percentage of iron in the sintered ore and the vanadium-titanium pellet ore is adjusted to be more than 56.8 percent in the smelting process, the binary alkalinity is 1.08-1.12, the coke ratio is 440kg/t of minus one-year coke, the coal ratio is 120kg/t of minus one-year coke, and the blast temperature is adjusted to be more than 1150 ℃.
A method for smelting schreyerite in a large-scale blast furnace under low-thermal-state strength coke comprises the following steps: the process smelting mechanism and the reasonable operation mode of the invention are as follows:
1. reduction and oxidation reaction mechanism for schreyerite smelting
The reduction reaction is carried out in the blast furnace of the common ore, and the indirect reduction (Fe) is carried out above the tuyere plane3O4+CO＝Fe2O3+CO2； Fe2O3+CO＝2FeO+CO2) The tuyere plane area is directly reduced (2FeO + C ═ 2Fe + CO)2). The vanadium-titanium ore blast furnace smelting is different from the common ore,which, in addition to following the above-mentioned reduction law, form crystalline titanium dioxide (TiO)2) Direct reduction is only carried out, and direct reduction (TiO) is carried out on the vanadium-titanium ore slagging zone below the plane of the common ore slagging zone (tuyere plane zone)2+2C ═ Ti +2CO) reaction, with emphasis on reduced titanium (Ti) and carbon monoxide (CO).
Since titanium (Ti) tends to form titanium carbide (TiC) and titanium nitride (TiN) with carbon (C) and nitrogen (N) in the hearth, and titanium carbide (TiC) and titanium nitride (TiN) cannot be melted at temperatures in the hearth of 1400 degrees or more, their melting temperatures are 2950 degrees and 3150 degrees, respectively. Therefore, TiC and TiN are main sources of the incomplete separation of vanadium-titanium magnetite slag and iron in blast furnace smelting.
Therefore, the oxygen-enriched air supply at the tuyere is improved, the oxygen-enriched air supply at the tuyere of the blast furnace is mainly used for assisting coke combustion, the smelting intensity is improved, the purposes of increasing the yield and saving coke are achieved, the titanium (Ti) in the iron slag solution is oxidized on the upper part of a hearth for the vanadium-titanium ore smelting in the blast furnace after the high oxygen enrichment rate is improved, and the oxidizing atmosphere (O) is maintained in the hearth range above the iron slag interface and below the slag forming zone plane of the vanadium-titanium ore2) Enabling titanium (Ti) to undergo an oxidation reaction (Ti + O)2＝TiO2) Formation of amorphous titanium dioxide (TiO)2) And hot-melt slag.
2. Carrying out operation and blending according to the characteristics of molten iron and slag for smelting vanadium and titanium:
(1) air supply system regulating means: a method for smelting schreyerite in large blast furnace by using coke with low thermal strength needs to increase the coal injection amount while increasing the oxygen-rich amount because the thermal strength of the coke is low. However, on the basis of the heat balance of the blast furnace, after the coal ratio is improved, the combustion amount of the coal powder in front of the tuyere is increased, the decomposition heat of the coal powder is increased, the radial length of a convolution area is shortened, edge airflow is increased, central airflow is weakened, the air permeability of a central dead material column is influenced, and the central airflow is inhibited.
Secondly, the air supply area is controlled to be 0.34m2Adjusted to 0.311m2To make the actual area of the tuyereThe air speed is kept at about 265m/s by matching with the air quantity entering the blast furnace, the air quantity is gradually increased to blow through the center, and the purposes of improving the air permeability of the blast furnace and opening the central air flow are achieved. Because the quality of the blast furnace coke is poor, the blast furnace coke is slowed down by reducing the air, the blast kinetic energy is reduced, and the height of the blocky belt is increased, so that the air permeability of the blast furnace is improved, but after the blast kinetic energy is reduced, in order to ensure the normal work of a furnace hearth and the normal distribution of air flow, the air speed is increased by adjusting the area of an air port, and the condition that the air speed is not greatly different from the normal production is ensured.
Because of oxygen (O)2) The reaction with titanium (Ti) is dynamic and particularly strong in oxidation performance, and the reaction capacity of the reaction is greater than the capacity of titanium (Ti) to combine with carbon (C) and nitrogen (N) in a relatively static state (nitrogen is an inert gas) to generate titanium carbide (TiC) and titanium nitride (TiN). Thus inhibiting the formation of refractory mixture of titanium carbide (TiC) and titanium nitride (TiN) at the temperature of the furnace hearth and achieving the effects of thorough slag-iron separation and smooth flow.
(2) The furnace temperature fluctuation range is large, and the phenomenon of overheating and supercooling is easy to occur. Firstly, the levels of silicon (Si) and titanium (Ti) in slag and iron melt are controlled well, so that the level of the silicon (Si) is controlled to be 0.20-0.30% and the level of the titanium (Ti) is controlled to be 0.15-0.20%. If the furnace temperature is overheated, sticky slag is easy to generate, slag and iron are not separated well, the furnace temperature needs to be reduced, and the control can be carried out by increasing schreyerite or reducing the coke consumption or reducing the furnace inlet air temperature; if the furnace temperature is too cold, the furnace temperature needs to be increased, and the adjustment and control can be carried out by reducing the vanadium-titanium ore fed into the furnace, increasing the coke fed into the furnace or increasing the temperature of the air fed into the furnace. If the furnace temperature is controlled stably, slag adhesion occurs, the amount of common ores can be increased in a limited way, and TiO in the slag is reduced2The content of (A) is less than 10%. Or adopting the measures of three highs: the pressure, the high wind temperature and the high humidity of the blast furnace top are regulated and controlled.
(3) Keeping the physical temperature of molten iron, controlling 1480-1510 ℃ according to the production practice PT (physical temperature), so as to ensure that the furnace hearth is active and the temperature is sufficient, and preventing the physical temperature. Making a proper air supply regulation and conditioning means: the furnace condition is stably distributed and adjusted according to the principle that the furnace temperature is adjusted according to the sequence of the wind temperature, the humidity, the coal powder and the oxygen enrichment when the furnace temperature fluctuates.
(4) Selecting a proper charging system: the regulation of the gas flow in the daily production of blast furnaces after the area of the tuyere and the distribution position are fixed mainly depends on the upper regulation, i.e. on the charging system. 2500m3The distribution mode of 'platform + funnel' is adhered to, the reasonable distribution of the edge airflow and the central airflow is ensured, the central airflow is stabilized through the funnel with a certain depth, and meanwhile, the stable and smooth edge ventilation is obtained. In the material distribution process, the distance between the material level platform and the furnace throat steel brick is 300mm, the width of the material level platform is controlled to be about 1.5m, and the depth of the central funnel is controlled to be 1.5-2 m, so that the material level is in a proper shape. And (4) batch weight selection is matched with air volume, the air volume is gradually reduced (adjusted from 4500 Nm/min to 4300Nm for cultivation/min), the batch weight is not adjusted, the batch speed is controlled within 44 +/-1 batches, and the air flow is stabilized.
(5) Molten iron and slag smelted from schreyerite have the characteristics of unavailable stopping and unavailable waiting in a hearth, and iron slag is required to be discharged frequently. And increasing the iron tapping times, namely the iron tapping times in day and night. The blast furnace adopts zero-interval tapping to prevent the phenomenon of wind holding caused by untimely discharge of iron slag; because the coke thermal strength is low, the air permeability and the liquid permeability of the hearth are poor, the iron is discharged from the ferroferric opening in turn under normal conditions, and the activation of the hearth is facilitated; ensuring that the depth of the tap hole is controlled to be 3600mm-3800mm, the stable mud beating amount is 200kg-250kg, controlling the tapping time, and opening the tap hole on time to ensure that the interval time is not more than 15 min; strictly managing the slag-appearing time, and carrying out overlapping tapping (opening two iron mouths) after the iron mouths are opened and no slag appears 40min later; and the mud sleeve management is enhanced, and the mud bleeding rate is reduced to below 1%.
(6) Establishing an evaluation index of the daily furnace conditions
A process for smelting schreyerite in large blast furnace under low-heat-state strength coke includes such steps as determining the comprehensive index of blast furnace, creating a system of furnace condition evaluation index and furnace-hearth activity index, reasonably evaluating the smooth running condition of blast furnace, and regulating the running parameters in time.
Claims (1)
1. A method for smelting schreyerite in a large-scale blast furnace under low-thermal-state strength coke is characterized in that
1. Selecting a proper furnace burden ore distribution structure:
(1) sintering ore: using the alkalinity R =1.8 of the existing eight-steel self-produced sinter;
(2) pellet ore: using vanadium-titanium pellets and Mongolian pellets, and adjusting the load of titanium in the furnace by increasing the proportion of the vanadium-titanium pellets;
(3) basic ore blending structure proportion: sintering ore: mongolian pelletizing: vanadium-titanium pellet = 75%: 17%: 8 percent; the specific components of the agglomerate, the vanadium-titanium pellet and the Mongolian pellet are shown in the following table:
TFe of total iron grade =56.7%, basicity of sinter =1.8, TiO2 load 21.4 Kg/t iron
2. Low hot strength coke index: the coking coal blending produced by the coke completely uses local coal, and the thermal state strength of the coke is 29.8 percent;
3. adjusting blast furnace operating parameters:
maintaining the indexes: coke load O/C: 4.142, oxygen enrichment is maintained at 15500 +/-100 m for carrying out the year/h, and the oxygen enrichment rate is as follows: 4.5% -5%, top temperature: 135 +/-5 ℃, wherein PT of molten iron is 1490-1510 ℃, and [ Si ]: 0.35-0.45, [ Ti ] < 0.20%, fuel ratio: 540-560 kg/t; the ash content of the coke is 11-13%, and M40 is more than or equal to 89.5%; the temperature of blast furnace inlet air is 1150-1250 ℃, and the oxygen-enriched amount accounts for 4-5% v/v of the inlet air amount; the furnace top pressure is 210 kPa; the mass percentage of iron in the sintered ore and the vanadium-titanium pellet ore is adjusted to be more than 56.8 percent in the smelting process, the binary alkalinity is 1.08-1.12, the coke ratio is 440kg/t of minus one-year coke, the coal ratio is 120kg/t of minus one-year coke, and the blast temperature is adjusted to be more than 1150 ℃.
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| 刘永想等: "八钢C高炉钒钛冶炼理论与实践", 《第十二届中国钢铁年会论文集——1.炼铁与原料》 * |
| 李佳俊等: "450m~3高炉钒钛矿冶炼理论与实践", 《云南冶金》 * |
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