A process for smelting chromium-containing hot metal in a blast furnace

Abstract

The present application provides a kind of process for smelting chromium-containing molten iron in blast furnace, which uses laterite nickel ore with 1.3-5.3% chromium ore as raw material, and produces chromium-containing molten iron through sintering + blast furnace smelting process; the proportion of each raw material is optimized and adjusted in the sintering stage, and the chromium content of sinter is controlled at 3.7-5.5%, and the sinter drum strength is greater than or equal to 53%; in the blast furnace smelting stage, the sinter is crushed, and the sinter with particle size above 4.5 mm obtained by separation is used as the sintering ore of blast furnace, the proportion of sintering ore in total sinter is greater than or equal to 55%, and the temperature of molten iron in blast furnace smelting is controlled at 1500-1530℃, the blast furnace condition is kept stable and smooth during the whole blast furnace smelting process, so that the recovery rate of chromium is kept above 89%, and the chromium-containing molten iron with chromium content of 6-7.5% is further smelted, and chromium-iron alloy is not needed to be added for smelting stainless steel, the cost is lower, and it has obvious economic efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of stainless steel smelting, and in particular to a process for smelting chromium-containing molten iron in a blast furnace. BACKGROUND

[0002] Low-nickel stainless steel containing a high chromium content, such as 200 series stainless steel (containing about 16% chromium), 300 series stainless steel (containing about 25% chromium), etc., when using a sintering + blast furnace smelting process, it usually first produces chromium-containing molten iron containing 2~3% chromium through sintering + blast furnace, and then adds chromium-iron alloy (such as high-carbon chromium iron) in the subsequent converter to increase the chromium content of the molten iron to the required chromium content of the finished stainless steel product.

[0003] With the deterioration of global mineral resources, the production cost of chromium-iron alloy is increasing, and as chromium is the second most important alloying element in 200 / 300 series stainless steel after nickel, solving the problem of high cost of chromium raw materials is crucial to the economic production of stainless steel and improving the competitiveness of enterprises. SUMMARY

[0004] The purpose of the present application is to provide a process for smelting chromium-containing molten iron in a blast furnace, which produces chromium-containing molten iron that can be directly smelted into stainless steel (without adding chromium-iron alloy) through sintering and blast furnace process, and compared with the existing process of producing stainless steel using chromium-iron alloy, the cost is lower, and it has obvious economic efficiency.

[0005] A process for smelting chromium-containing molten iron in a blast furnace, comprising the following steps:

[0006] Sintering

[0007] The ore is first prepared before sintering. The weight percentage of laterite nickel ore, quicklime, chromium ore, and fuel in the prepared ore is as follows, based on the total weight of the prepared ore being 100%:

[0008] Table 1

[0009]

[0010] After the prepared ore is mixed and transferred to the sintering machine for sintering, the chromium content of the sintered ore obtained by sintering is controlled at 3.7~5.5%, and the sintered ore drum strength is ≥53%;

[0011] (2) Blast furnace smelting

[0012] The sintered ore obtained in step (1) is crushed, and the sintered ore with a particle size of 4.5 mm or more obtained through separation is used as the sintered ore for blast furnace, and the proportion of the sintered ore for blast furnace in the total amount of the sintered ore obtained in step (1) is greater than or equal to 55%, the sintered ore for blast furnace and fuel are put into a blast furnace together for smelting, the initial chromium content of the molten iron of the blast furnace is controlled to be 6-8%, the temperature of the molten iron in the process of blast furnace smelting is controlled to be 1500-1530 DEG C, the blast furnace condition is kept stable and smooth during the whole process of blast furnace smelting, wherein the blast furnace air pressure fluctuation is within ±20 kPa, and the top temperature fluctuation is within ±50 DEG C, so that the chromium recovery rate is kept to be greater than or equal to 89%, and the molten iron with a chromium content of 6-7.5% (i.e., the final chromium content of the molten iron is 6-7.5%) is further smelted.

[0013] The present inventors use low-nickel laterite ore plus chromium ore as raw materials, and produce molten iron containing chromium which can be directly smelted into stainless steel through the process of sintering + blast furnace smelting, and the following problems are mainly faced in the smelting process:

[0014] (1) The use of chromium ore reduces the strength and ore-forming rate of the chromium-containing sintered ore: because the melting point of Cr2O3 in the chromium ore is relatively higher than that of Fe2O3, and according to the behavior of Cr in the blast furnace and the refining furnace in practice by the present inventors: Cr is a difficult-to-reduce and easy-to-oxidize substance, and requires a high reduction temperature, therefore, under the condition that the reduction temperature is not high enough in the sintering process, the chromium ore does not melt and is difficult to reduce, and it is also difficult to form a liquid phase combined with other substances, which is theoretically not conducive to sintering production.

[0015] (2) It is difficult to control the blast furnace temperature: the control of the blast furnace temperature is directly related to the chromium recovery rate, the higher the blast furnace temperature, the higher the chromium recovery rate, but at the same time, the fuel consumption is also higher, in addition, if the blast furnace temperature is too low or too high, it will also affect the stable and smooth operation of the blast furnace, how to control the most suitable blast furnace temperature to achieve the best balance among the chromium recovery rate, fuel consumption and blast furnace condition (i.e., stable and smooth operation of the blast furnace without obvious fluctuation) is the difficulty of chromium molten iron smelting.

[0016] In the process of ore matching before sintering, the chrome ore is one of the sources of chromium, and by adding the chrome ore in the ore matching, the purpose of increasing the chromium content in the ore matching is achieved. From the change relationship between the chromium content of the sinter and the chromium content of the molten iron of the blast furnace, it can be seen that: increasing the chromium content of the sinter to 4.7%, using the sinter with such high chromium content to carry out subsequent blast furnace smelting, the sinter is melted in the blast furnace to form molten iron and slag system, and the initial chromium content of the molten iron corresponding to the sinter with the chromium content of 4.7% can theoretically reach 8.23%, but the chromium content of the molten iron in the middle and later stages of the blast furnace smelting will show a significant downward trend, that is, the higher the chromium content, the lower the recovery rate will be, and the final chromium content of the molten iron is only 7.10%, and the recovery rate of chromium is only 85%, at the same time, there are multiple obvious fluctuations in the furnace condition during the blast furnace smelting. Based on this, the present inventors strictly control the addition amount of the chrome ore, so that the chromium content of the sinter is only increased from the original 2.84% to 3.7~4.1%, while increasing the amount of the chrome ore used to increase the chromium content of the sinter, the amount of the chrome ore used and the chromium content of the sinter are also controlled to be not too high to cause excessive increase of the sinter fuel consumption, and the fuel is increased from the original 5.4% to 6.1~6.5%, so that the sinter with a drum strength of ≥53.0% can be produced, and the sinter fuel consumption is controlled at a low level while solving the above-mentioned problem of “decrease of the sinter strength after using the chrome ore”.

[0017] Moreover, the present application maintains a high sinter drum strength (≥53%), so that the proportion (≥55%, also called “ore forming rate”) of the sintered body obtained after sintering and then broken to obtain the sinter with a particle size of ≥4.5 mm is higher, the raw material utilization rate is improved, and the raw material cost is reduced. At the same time, the high sinter drum strength makes the proportion of the sinter with a particle size of ≥16 mm in the sinter obtained by breaking increased from 51.9 to more than 52.5%, which is beneficial to improve the overall permeability of the sinter charged into the blast furnace, and thus is beneficial to maintain the stable and smooth operation of the blast furnace.

[0018] In the blast furnace smelting step, the present inventors start from two aspects of controlling the blast furnace fuel consumption at a low level and improving the chromium recovery rate to reduce the blast furnace smelting cost.

[0019] If the final chromium content of the molten iron is to be increased, the recovery rate of chromium must be ensured, and the blast furnace temperature and the temperature of the molten iron must be increased, and when the final chromium content of the molten iron is increased to 8% or more, the increase of the temperature of the molten iron will lose the control of silicon, so that the silicon dioxide in the slag is reduced and enters the molten iron, so that the silicon content in the molten iron exceeds the standard, and at the same time, the slag acid-base ratio is out of balance, the fluidity is poor, and it is not easy to discharge, which easily causes the difficulty of tapping at the blast furnace, so that the blast furnace is difficult to operate. In addition, the fuel consumption will also be greatly increased. Therefore, the present application selects to increase the final chromium content of the molten iron to only 6~7.5%.

[0020] Meanwhile, considering that the reduction temperature of low-nickel laterite ore is 1200 DEG C, the reduction temperature of chromium ore is 1450 DEG C, and the reduction temperature of silicon is 1450-1650 DEG C, the inventors hope that as much chromium as possible can be reduced to improve the chromium recovery rate, and as little silicon as possible can be reduced to avoid the increase of fuel consumption caused by the absorption of a large amount of heat during the reduction of silicon (generally, the reduction of silicon needs to absorb a large amount of heat, and the heat required for the reduction of a unit mole of silicon is 8 times the heat required for the reduction of the same amount of pig iron). Therefore, the inventors design the best molten iron temperature of the blast furnace molten iron in the range of 1450-1560 DEG C. Further, the inventors find in the test that the higher the temperature of the molten iron, the higher the chromium recovery rate, but when the temperature of the molten iron is higher than 1530 DEG C, the change of the chromium recovery rate is not obvious, therefore, the temperature of the molten iron is controlled in the range of 1500-1530 DEG C, at this time, a higher Cr recovery rate can be obtained, and the influence of the large increase of fuel consumption caused by the excessively high temperature of the hearth can be reduced. Therefore, by adjusting the sintering step, and further smelting the chromium-containing molten iron with the chromium content of 6-7.5% by controlling the chromium content in the chromium-containing molten iron obtained by the blast furnace to 6-8% and the temperature of the molten iron to 1500-1530 DEG C, the fuel consumption of the blast furnace can be controlled at a lower level, a higher chromium recovery rate (more than 89%) can be obtained, and the steelmaking cost can be reduced to the maximum. Compared with the existing alloy smelting process, by controlling the increase of the raw material cost of the fuel and the chromium ore powder, the total raw material cost can be reduced, and the purpose of reducing the stainless steel smelting cost can be achieved.

[0021] The process for smelting the chromium-containing molten iron by the blast furnace can keep the chromium recovery rate to be more than 89%. Meanwhile, the proportion of the sinter with the particle size of more than 16 mm in the sinter entering the blast furnace is 52.5-53%, which is beneficial to the stable and smooth operation of the blast furnace.

[0022] Preferably, the technical parameters of the sintering process in the step (2) are as follows:

[0023] Table 2

[0024]

[0025] Preferably, the ore blending in the step (1) further comprises iron oxide scale (i.e. iron chips produced by the falling of the surface oxidation layer of the ingot and billet during the rolling process) or / and stainless steel dust. The iron oxide scale or / and the stainless steel dust can replace part of the chromium concentrate powder in the ore blending, so as to achieve the purpose of further saving the raw material cost.

[0026] Preferably, the chromium content of the molten iron in step (2) is 6-7.5%, the turnover rate of the molten iron ladle is 2-3 hours, and the capacity of the molten iron ladle is controlled to be 65-70 tons per ladle. The higher the temperature of the molten iron, the faster the temperature loss at room temperature. Due to the increase of the chromium content in the molten iron of the present application, the melting point increases, and it is necessary to transfer to the next process (secondary smelting of the steelmaking converter) as soon as possible to prevent the molten iron from freezing and solidifying due to the decrease of the temperature, and the production yield of the finished product is also lost, which will also cause the increase of the production cost. Therefore, the present application improves the molten iron ladle turnover, reduces the empty ladle time, reduces the influence of the molten iron ladle closing, at the same time, increases the ladle filling capacity, avoids the incomplete filling of the ladle and the half ladle iron, causes the molten iron ladle to stick, and thus improves the phenomenon that the molten iron with high viscosity is easy to stick to the ladle.

[0027] Preferably, the fuel in step (2) includes coke, and the coke has a thermal intensity of ≥56%; at the same time, the coke quality is improved, and when the coke has a thermal intensity of ≥56%, the blast furnace basically has no material collapse, and when the coke has a thermal intensity of less than 54%, the material collapse of the blast furnace is obvious. The blast furnace fluctuation includes air pressure fluctuation, top temperature fluctuation and material collapse, and the blast furnace fluctuation will cause physical heat loss or heat loss, thereby reducing the reduction of Cr2O3 and affecting the chromium recovery rate. Embodiment

[0028] The preferred embodiment of the process for smelting molten iron containing chromium in a blast furnace of the present application will be described in detail as follows:

[0029] Taking the production of molten iron containing chromium for 201 series stainless steel as an example.

[0030] The process for smelting molten iron containing chromium in a blast furnace of the present application is used to prepare molten iron containing chromium for the production of 201 series stainless steel, and two embodiments are provided, in which the chromium content of the molten iron containing chromium is designed to be about 6.5% (Example 1) and about 7.5% (Example 2), respectively. At the same time, the existing process for smelting molten iron containing chromium in a blast furnace is used to produce 201 series stainless steel as a comparative example (Comparative Example 1).

[0031] The process for smelting molten iron containing chromium in a blast furnace of the present application comprises the following steps:

[0032] (1) Sintering

[0033] The ore proportioning before sintering is carried out, and the weight percentage of each raw material in the ore proportioning is as follows, taking the total weight of the ore proportioning as 100%:

[0034] Table 3

[0035]

[0036] The laterite nickel ore used in Comparative Example 1, Example 1 and Example 2 is a low-aluminum laterite nickel ore with a chromium content of 1.6-3.1, and the chemical composition is specifically as follows:

[0037] Table 4

[0038]

[0039] The quicklime and fuel are both raw materials commonly used in stainless steel smelting, and are basically free of Cr.

[0040] The chromium ore is selected from a chromium ore with a chromium content (net value) of ≥27%, and can be specifically a chromium ore with a brand of G-30, G-38 or G-40. The chemical composition requirements of the G-30, G-38 or G-40 chromium ore are as follows:

[0041] Table 5

[0042]

[0043] The particle size requirement is that the proportion of particles with a particle size of ≤2 mm is <10%.

[0044] The iron oxide scale is iron filings produced by the surface oxide layer of steel ingots and billets falling off during rolling, and the chromium content is usually 6.5-10%.

[0045] The stainless steel dust is dust from a steelmaking plant, and the chromium content is usually 1-12%.

[0046] After the ore is mixed and uniformly transferred to a sintering machine for sintering, the technical parameters of sintering are specifically as follows:

[0047] Table 2

[0048]

[0049] The composition of the sintered ore obtained by sintering in Example 1 and Example 2 is controlled to meet the following requirements:

[0050] Table 6

[0051] Meanwhile, the tumbler strength of the sintered ore is ≥53%, and the tumbler strength, ore-forming rate and the proportion of sintered ore with a particle size of ≥16 mm to blast furnace charging sintered ore are specifically as follows:

[0052] Table 7

[0053]

[0054] (2) Blast furnace smelting

[0055] The sinter obtained in step (1) is crushed, and the sinter with a particle size of more than 4.5 mm obtained through separation is used as the sinter into the blast furnace, and the proportion of the sinter into the blast furnace in the total amount of the sinter obtained in step (1) (i.e., the sinter production rate) is ≥55%. The sinter into the blast furnace is put into the blast furnace for smelting, and the initial chromium content of the molten iron in the blast furnace is generally 6-8%. The temperature of the molten iron in the smelting process of the blast furnace is controlled at 1500-1530°C, and the blast furnace is kept stable and smooth during the whole smelting process. The blast pressure fluctuation is within ±20 kPa, and the top temperature fluctuation is within ±50°C, so that the chromium recovery rate is kept ≥89%, and the molten iron with a chromium content of 6-7.5% is further smelted.

[0056] When the blast furnace is stable and smooth, there is no collapse or sliding of the material in the furnace, and the material descends uniformly and stably. The material size record shows that the material stably descends, the time interval between adjacent material batches is uniform, and the material line depth remains fixed.

[0057] Table 8

[0058]

[0059] The fuel consumption cost and raw material cost of the process of smelting molten iron with chromium in the blast furnace of Example 1 and Comparative Example 1 are shown in the following table:

[0060] Table 9

[0061]

[0062] Although the cost of the process of smelting molten iron with chromium in the blast furnace of Example 1 is increased by 114.72 yuan / t compared with that of Comparative Example 1, the chromium content of the obtained molten iron is increased by about 2% compared with that of Comparative Example 1.

[0063] On July 13, 2023, the market price of high-carbon chromium iron was about 8550-8750 yuan / 50 base tons (converted to 175 yuan / degree), and the price of chromium ore was about 58 yuan / degree. Compared with chromium ore, the price of high-carbon chromium iron per degree of chromium point (i.e., the molten iron chromium content is increased by 1%) is higher: 175-58=117 yuan. Assuming that 100,000 tons of 201 stainless steel are produced per month, 350 yuan of high-carbon chromium iron is needed to smelt 201 stainless steel using the molten iron with chromium obtained in Comparative Example 1, i.e., the cost of high-carbon chromium iron for smelting 201 stainless steel in Comparative Example 1 is 350 yuan / ton, and no additional high-carbon chromium iron is needed to smelt 201 stainless steel using the molten iron with chromium obtained in Example 1, i.e., the cost of high-carbon chromium iron is 0. After deducting the cost increase of 114 yuan / t caused by the smelting of molten iron with chromium in the blast furnace of Example 1, the net saving is 236 yuan / ton×100,000 tons=2,360,000 yuan / month.

[0064] The fuel consumption cost and raw material cost of the process of Example 2 and Comparative Example 1 for smelting the chromium-containing molten iron in a blast furnace are shown in the following table:

[0065] Table 10

[0066]

[0067] The cost of the process of Example 2 for smelting the chromium-containing molten iron in a blast furnace is 2.93 yuan / t higher than that of Comparative Example 1, but the chromium content of the obtained molten iron is about 3% higher than that of Comparative Example 1.

[0068] Taking the production of 201 stainless steel at 100,000 tons per month as an example, the chromium-containing molten iron obtained by Comparative Example 1 is used to smelt 201 stainless steel, and the cost of high-carbon chromium iron of 175*2=350 yuan / t is needed for each ton of molten steel, that is, the cost of high-carbon chromium iron for smelting 201 stainless steel by Comparative Example 1 is 350 yuan / t, and the cost of high-carbon chromium iron for smelting 201 stainless steel by Example 2 is 0. After deducting the cost increase of 2.93 yuan / t of the process of Example 2 for smelting the chromium-containing molten iron in a blast furnace, the net saving is nearly 347 yuan / t*100,000 tons=3,470,000 yuan / month.

[0069] The inventors also investigated the influence of the chromium content of the sintered ore on the chromium content of the molten iron in the blast furnace during the test process, and the relationship between the chromium content of the sintered ore and the change of the chromium content of the molten iron in the blast furnace is shown in the following table.

[0070] Table 11

[0071]

[0072] In addition, the inventors also investigated the Cr recovery rate at different molten iron temperatures during the smelting process in the blast furnace:

[0073] Table 12

[0074]

[0075] As can be seen from the above table, the molten iron temperature range for the Cr content of the molten iron of 6.5% is divided into four intervals, the higher the temperature, the more obvious the Cr recovery rate; when the molten iron temperature is increased to above 1530℃, the Cr recovery rate changes slightly; therefore, the temperature of the chromium-enriched molten iron is controlled at 1500-1530℃, which is the best, and a higher Cr recovery rate can be obtained, and at the same time, the influence of the increase of fuel consumption due to the too high temperature of the furnace hearth can be reduced.

[0076] And the present inventors have also found in experiments that when the end-point chromium content of the hot metal is increased to 8% or above, the temperature of the hot metal must be further increased, and the increase in the temperature of the hot metal will lose the control of silicon, so that the silicon dioxide in the slag is reduced into the hot metal, the silicon content in the hot metal exceeds the standard, and the slag acid-base ratio is out of balance, the fluidity is poor, and the hot metal is not easy to discharge, which causes the difficulty in tapping at the blast furnace, and the blast furnace is difficult to operate. In addition, the fuel consumption is also greatly increased. Therefore, the present application selects to increase the end-point chromium content of the hot metal to only 6-7.5%.

[0077] In the ore matching before sintering of the present application, the iron oxide scale (i.e. the iron filings produced by the surface oxide layer of the ingot and billet falling off in the rolling process) or / and the stainless steel dust can be added, or the iron oxide scale and the stainless steel dust can not be added.

[0078] Preferably, the turnover rate of the hot metal tank containing the chromium-containing hot metal prepared in step (2) of the present application is 2-3 hours, and the capacity of the hot metal tank is controlled to be 65-70 tons / tank. The higher the temperature of the hot metal, the faster the temperature loss at room temperature. Since the content of chromium in the chromium-containing hot metal of the present application is increased, the melting point is increased, and it is necessary to transfer to the next process (secondary smelting of the steelmaking converter) as soon as possible to prevent the hot metal from freezing and solidifying due to the decrease in temperature, and the loss of product yield and the increase in production cost caused by the freezing and solidification of the hot metal due to the decrease in temperature. Therefore, the present application also increases the turnover rate of the hot metal tank from the existing 5 hours to 3 hours, reduces the empty tank time, and reduces the influence of the hot metal tank sticking. At the same time, the present application also increases the capacity of the hot metal tank from the existing 50 tons / tank to more than 65 tons / tank, increases the tank filling amount, avoids the incomplete filling of the tank and the half-tank iron, causes the hot metal tank to stick, and improves the phenomenon that the hot metal with high viscosity is easy to stick to the tank.

[0079] Preferably, the fuel in step (1) and step (2) comprises coke, and the coke selected has a thermal intensity of ≥56%; at the same time, the coke quality is improved, and when the coke with a thermal intensity of ≥56% is selected, the blast furnace is basically free of material collapse, and when the thermal intensity of the coke is less than 54%, the material collapse of the blast furnace is obvious. The fluctuation of the blast furnace includes the fluctuation of the air pressure, the fluctuation of the top temperature and the collapse of the material, and the fluctuation of the blast furnace will cause physical heat loss or heat loss, thereby reducing the reduction of Cr2O3 and affecting the chromium recovery rate.

[0080] The usage amount of the chromium ore in the present application can be, but is not limited to, 1.3% and 4.0% in the specific embodiments, and the sources of the chromium element in the ore blending mainly include the chromium ore, the laterite nickel ore, the oxide scale and the stainless steel dust. In smelting the nickel-containing stainless steel, the addition amount of the laterite nickel ore is relatively fixed, and the chromium element in the stainless steel mainly comes from the chromium ore except the laterite nickel ore, meanwhile, the oxide scale and the stainless steel dust can replace part of the chromium ore to provide the chromium, as long as the composition of the sintered ore obtained by sintering meets the requirements of the present application. When the addition amount of the oxide scale and the stainless steel dust is 0 in the ore blending, in order to smelt the molten iron containing chromium with the chromium content of 7.5%, theoretically, the addition amount of the chromium ore is 5.3%.

[0081] From the difficulty of the metal enrichment reduction, in the selection of the chromium ore, the higher the chromium content of the chromium ore is, the better, but from the perspective of the production cost, the most economical one is the most reasonable production mode, and the selected chromium ore is determined by the market price.

[0082] The present application can make several simple deductions or substitutions without departing from the concept of the present application for the ordinary skilled person in the technical field of the present application, and all of them should be regarded as belonging to the protection scope of the present application.

Claims

1. A process for smelting chromium-containing molten iron in a blast furnace, characterized in that, Includes the following steps: (1) Sintering First, the ore is blended before sintering. Based on the total weight of the blended ore (100%), the weight percentages of laterite nickel ore, quicklime, chromite, and fuel in the blend are as follows: After the ore is mixed evenly, it is transferred to a sintering machine for sintering, and the chromium content of the sintered ore is controlled between 3.7% and 4.67%, and the drum strength of the sintered ore is ≥58%. (2) Blast furnace smelting The sinter obtained in step (1) is crushed, and the sinter with a particle size ≥ 4.5 mm obtained by sorting is used as the sinter for the blast furnace. The proportion of the sinter for the blast furnace to the total amount of sinter obtained in step (1) is ≥ 55%. The sinter for the blast furnace and fuel are fed into the blast furnace for smelting. The initial chromium content of the molten iron is controlled at 6~8%. The temperature of the molten iron is controlled at 1500~1530°C during the blast furnace smelting process. The blast furnace condition is kept stable and smooth throughout the blast furnace smelting process. The blast furnace wind pressure fluctuation is within ±20 kPa and the top temperature fluctuation is within ±50 degrees. Thus, the chromium recovery rate is kept at ≥ 89%, and chromium-containing molten iron with a chromium content of 6~7.53% is obtained by further smelting. The proportion of sinter with a particle size of 16 mm or larger in the sinter fed into the furnace is 52.5-53%.

2. The process for smelting chromium-containing molten iron in a blast furnace according to claim 1, characterized in that: The technical parameters for the sintering process in step (1) are as follows: 。 3. The process for smelting chromium-containing molten iron in a blast furnace according to claim 1, characterized in that: The turnover rate of the molten iron containing chromium with a chromium content of 6-7.53% in step (2) is 2-3 hours, and the capacity of the molten iron ladle is controlled at 65-70 tons / ladle.

4. The process for smelting chromium-containing molten iron in a blast furnace according to claim 1, characterized in that: The fuel mentioned in step (2) includes coke, and the coke is selected with a thermal strength ≥ 56%.

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