A dephosphorization agent for converter steelmaking and its preparation method and use
By using specific proportional dephosphorizers for cured cast residue, lime and light calcined materials, the problems of large iron loss and slow slag formation in the dephosphorization stage in converter steelmaking are solved, and low oxidation and low consumption dephosphorization are achieved Effect.
Patent Information
- Application Number
- CN202310215643.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-03-08
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2043-03-08
AI Technical Summary
During the dephosphorization stage of converter steelmaking, there is a lot of lime and slag-decomposition materials added, resulting in large iron losses, slow slag-forming speed and unsatisfactory slag-forming effect.
Dephosphorizer composed of cured cast residue, lime and light sintering materials is used to reduce the amount of lime added through specific ratios and additives, improve the slag formation speed and slag removal effect, and reduce iron loss and environmental protection costs.
It is achieved without affecting the dephosphorization effect, reducing the amount of dephosphorization agent added, improving the slag formation speed and slag removal effect, and reducing iron loss and environmental protection costs.
Smart Images
Figure BDA0004114784510000141 
Figure BDA0004114784510000151
Abstract
Description
Technical Field
[0001] The invention relates to the field of converter steelmaking, and in particular to a converter steelmaking dephosphorization agent and a preparation method and application thereof. Background Art
[0002] At present, as users have higher and higher requirements for the quality of steel products, the phosphorus content in most products is required to be below 0.025%. The prices of various raw and auxiliary materials in the market continue to rise. Low-phosphorus steels such as wind power bearings even require the phosphorus content of molten steel to be ≤0.010%. In order to ensure that the phosphorus content meets the standard, the converter generally uses highly oxidizing slag for dephosphorization.
[0003] For example, CN107130085A discloses a highly efficient dephosphorization accelerator suitable for converter steelmaking and a preparation method thereof. The innovation lies in using converter steelmaking dust removal ash as the base material, effectively utilizing its high iron oxide component and active calcium oxide component, and recycling waste resources of steelmaking plants. At the same time, active BaO material is introduced. The barium phosphate formed by BaO has stronger thermodynamic stability than calcium phosphate, forming a highly oxidizable, highly alkaline, low melting point dephosphorization accelerator composed of Fe2O3, CaO, and BaO substances, achieving the purpose of supplementing FeO in the converter steelmaking process and forming a stable dephosphorization product, so as to enhance the dephosphorization efficiency and finally achieve efficient dephosphorization. This method can save more than 30% of the cost, and the dephosphorization efficiency is increased by about 5-10% compared with the traditional dephosphorization agent. At the same time, the product of this scheme effectively protects the environment, saves energy, realizes the efficient utilization of resources of "turning waste into treasure" of solid waste in steelmaking plants, achieves good economic and social benefits, and is suitable for promotion and use.
[0004] CN103882178A A converter steelmaking process for recycling converter final slag belongs to the technical field of converter steelmaking. The converter blowing process is divided into two parts, namely, the dephosphorization stage and the decarburization stage. Before the dephosphorization stage blowing begins, 0-70 kg / t of converter final slag in a cooled state is first added, and then iron and scrap steel are added for blowing in the dephosphorization stage. The blowing process produces slag with low FeO content. After the blowing is completed, the slag is poured, and then the decarburization period is entered. After the decarburization period blowing is completed, carbon is pulled and steel is tapped. The converter terminal slag is left inside the converter for use in the next furnace blowing and dephosphorization stage. The advantage is that the converter slag is used to the greatest extent, and the smelting of low TFe of dephosphorization slag further reduces the loss of steel materials.
[0005] However, in the current converter steelmaking, a lot of lime and slag-forming materials are added during the dephosphorization stage, resulting in large iron loss, slow slagging speed and unsatisfactory slagging effect. Summary of the invention
[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a converter steelmaking dephosphorization agent and a preparation method and use thereof, so as to solve the problem that a large amount of lime and slagging materials are added in the dephosphorization stage of the current converter steelmaking, resulting in large iron loss, slow slagging speed and unsatisfactory slagging effect.
[0007] To achieve this object, the present invention adopts the following technical solutions:
[0008] In a first aspect, the present invention provides a converter steelmaking dephosphorization agent, which comprises, by weight: 7-12 parts of solidified casting slag, 7-21 parts of lime, and 2-19 parts of light burnt material.
[0009] The converter steelmaking dephosphorization agent provided by the present invention can achieve the target requirements of small slag amount, low oxidizability and low consumption without affecting dephosphorization and production.
[0010] In the present invention, the solidified casting slag comprises, by mass percentage, 50-54% CaO, 24-26% Al2O3, 5-6% MgO, 8-9% SiO2, 0.06-0.08% V2O5, 0.3-0.4% MnO, 1.1-1.2% S and 0.7-0.8% TFe, the total being 100%, of which 0.4-0.5% FeO.
[0011] In the present invention, the CaO content in the solidified casting slag is 50-54% by mass percentage, for example, it can be 50%, 50.2%, 50.4%, 50.6%, 50.8%, 51%, 51.2%, 51.4%, 51.6%, 51.8%, 52%, 52.2%, 52.4%, 52.6%, 52.8%, 53%, 53.2%, 53.4%, 53.6%, 53.8% or 54%, but is not limited to the listed values, and other values not listed within the range are equally applicable.
[0012] In the present invention, the mass percentage of Al2O3 in the solidified casting slag is 24-26%, for example, it can be 24%, 24.1%, 24.2%, 24.3%, 24.4%, 24.5%, 24.6%, 24.7%, 24.8%, 24.9%, 25%, 25.1%, 25.2%, 25.3%, 25.4%, 25.6%, 25.7%, 25.8%, 25.9% or 26%, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0013] In the present invention, the mass percentage of MgO in the solidified casting slag is 5-6%, for example, it can be 5%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%, 5.7%, 5.8%, 5.9% or 6%, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0014] In the present invention, the mass percentage of SiO2 in the solidified casting slag is 8-9%, for example, it can be 8%, 8.1%, 8.2%, 8.3%, 8.4%, 8.5%, 8.6%, 8.7%, 8.8%, 8.9% or 9%, etc., but is not limited to the listed values, and other unlisted values within this range are also applicable.
[0015] In the present invention, the mass percentage of V2O5 in the solidified casting slag is 0.06-0.08%, for example, it can be 0.06%, 0.061%, 0.062%, 0.063%, 0.064%, 0.065%, 0.066%, 0.067%, 0.068%, 0.069%, 0.07%, 0.071%, 0.072%, 0.073%, 0.074%, 0.075%, 0.076%, 0.078%, 0.079% or 0.08%, etc., but is not limited to the listed values, and other values not listed within the range are also applicable.
[0016] In the present invention, the mass percentage of MnO in the solidified casting slag is 0.3-0.4%, for example, it can be 0.3%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39% or 0.4%, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0017] In the present invention, the S content in the solidified casting slag is 1.1-1.2% by mass percentage, for example, it can be 1.1%, 1.11%, 1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%, 1.18%, 1.19% or 1.2%, etc., but is not limited to the listed values, and other unlisted values within this range are also applicable.
[0018] In the present invention, the mass percentage of TFe in the solidified casting slag is 0.7-0.8%, for example, it can be 0.7%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79% or 0.8%, etc., but is not limited to the listed values, and other values not listed within the range are also applicable.
[0019] In the present invention, the solidified casting slag in the converter steelmaking dephosphorization agent is 7-12 parts by weight, for example, it can be 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, 10 parts, 10.5 parts, 11 parts, 11.5 parts or 12 parts, but is not limited to the listed values, and other unlisted values within this range are also applicable.
[0020] In the present invention, the amount of lime in the converter steelmaking dephosphorization agent is 7-21 parts by weight, for example, it can be 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.2, 20.4, 20.6, 20.8 or 21 parts, etc., but is not limited to the listed values, and other values not listed within the range are equally applicable.
[0021] In the present invention, the light-burned material in the converter steelmaking dephosphorization agent is 2-19 parts by weight, for example, it can be 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, 10 parts, 10.5 parts, 11 parts, 11.5 parts, 12 parts, 12.5 parts, 13 parts, 13.5 parts, 14 parts, 14.5 parts, 15 parts, 15.5 parts, 16 parts, 16.5 parts, 17 parts, 17.5 parts, 18 parts, 18.5 parts or 19 parts, but is not limited to the listed values, and other values not listed within this range are equally applicable.
[0022] As a preferred technical solution of the present invention, the solidified casting slag is obtained by treating the ladle casting slag with an additive, specifically, the casting slag is solidified with an additive to obtain the solidified casting slag.
[0023] Preferably, the additives include, by mass percentage, 33-34% magnesium oxide, 15-16% boron oxide, 18-19% silicon oxide, 8-15% aluminum oxide, and the balance is calcium oxide.
[0024] In the present invention, the mass percentage of magnesium oxide in the additive is 33-34%, for example, it can be 33%, 33.1%, 33.2%, 33.3%, 33.4%, 33.5%, 33.6%, 33.7%, 33.8%, 33.9% or 34%, but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0025] In the present invention, the mass percentage of boron oxide in the additive is 15-16%, for example, it can be 15%, 15.1%, 15.2%, 15.3%, 15.4%, 15.5%, 15.6%, 15.7%, 15.8%, 15.9% or 16%, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0026] In the present invention, the mass percentage of silicon oxide in the auxiliary agent is 18-19%, for example, it can be 18%, 18.1%, 18.2%, 18.3%, 18.4%, 18.5%, 18.6%, 18.7%, 18.8%, 18.9% or 19%, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0027] In the present invention, the mass percentage of aluminum oxide in the additive is 8-15%, for example, it can be 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5% or 15%, etc., but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0028] Preferably, the additive is added in an amount of 2-4% of the mass of the ladle casting slag, for example, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9% or 4%, etc., but is not limited to the listed values, and other values not listed within the range are equally applicable.
[0029] As a preferred technical solution of the present invention, the particle size of the solidified casting slag is 10-30 mm;
[0030] Preferably, the particle size of the lime is 5-10 mm;
[0031] Preferably, the light-burned material comprises light-burned dolomite;
[0032] Preferably, the particle size of the light fuel is 5-10 mm.
[0033] In the present invention, solidified casting slag, lime and light burnt material are particle aggregates composed of particles of a single particle size within a limited range or aggregates of all particles within a certain particle size range, such as aggregates of 20 mm particles, aggregates of 10 mm particles, aggregates of 6 mm particles, aggregates of 5 mm particles, aggregates of 15 mm particles, aggregates of all solid particles within a particle size range of 10-22 mm, aggregates of all solid particles within a particle size range of 20-30 mm, aggregates of all solid particles within a particle size range of 5-7 mm, aggregates of all solid particles within a particle size range of 6-10 mm, etc.
[0034] In a second aspect, the present invention provides a method for preparing the converter steelmaking dephosphorization agent as described in the first aspect, the preparation method comprising:
[0035] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0036] In a third aspect, the present invention provides a use of the converter steelmaking dephosphorization agent as described in the first aspect, wherein the use comprises dephosphorizing molten iron using the converter steelmaking dephosphorization agent, specifically comprising:
[0037] The converter steelmaking dephosphorization agent is added into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag.
[0038] As a preferred technical solution of the present invention, the converter steelmaking dephosphorization agent is added into the converter through a high-level silo.
[0039] As a preferred technical solution of the present invention, the addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 8-13kg / t steel, for example, 8kg / t steel, 8.2kg / t steel, 8.4kg / t steel, 8.6kg / t steel, 8.8kg / t steel, 9kg / t steel, 9.2kg / t steel, 9.4kg / t steel, 9.6kg / t steel, 9.8kg / t steel, 10kg / t steel, 10.2kg / t steel, 10.4kg g / t steel, 10.6kg / t steel, 10.8kg / t steel, 11kg / t steel, 11.2kg / t steel, 11.4kg / t steel, 11.6kg / t steel, 11.8kg / t steel, 12kg / t steel, 12.2kg / t steel, 12.4kg / t steel, 12.6kg / t steel, 12.8kg / t steel or 13kg / t steel, etc., but not limited to the listed values, other unlisted values within the range are equally applicable.
[0040] As a preferred technical solution of the present invention, the dephosphorization treatment time is 6-7min, for example, it can be 6min, 6.05min, 6.1min, 6.15min, 6.2min, 6.25min, 6.3min, 6.35min, 6.4min, 6.45min, 6.5min, 6.55min, 6.6min, 6.65min, 6.7min, 6.75min, 6.8min, 6.85min, 6.9min, 6.95min or 7min, but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0041] As a preferred technical solution of the present invention, the terminal temperature of the molten steel obtained after the dephosphorization treatment is ≥1630°C, for example, it can be 1630°C, 1635°C, 1640°C, 1645°C, 1650°C, 1655°C, 1660°C, 1665°C, 1670°C, 1675°C, 1680°C, 1685°C, 1690°C, 1695°C or 1700°C, but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0042] As a preferred technical solution of the present invention, the use includes: adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain the final molten steel and the converter final slag;
[0043] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0044] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 8-13 kg / t steel;
[0045] The dephosphorization time is 6-7min;
[0046] The terminal temperature of the molten steel obtained after the dephosphorization treatment is ≥1630°C.
[0047] Compared with the prior art solutions, the present invention has the following beneficial effects:
[0048] (1) The present invention solidifies the ladle casting slag through an auxiliary agent, and the solidified casting slag is added to the converter through the converter high-level silo for use. The solidified casting slag is fed into the converter, which reduces the amount of lime added to the converter on the one hand, and effectively improves the slag forming speed and slag-removing effect of the converter on the other hand, thereby reducing the transportation cost and environmental protection cost of the ladle casting slag.
[0049] (2) In the present invention, the dephosphorization agent is configured by using a specific ratio of low-melting-point solidified casting slag, lime, and light clinker. On the basis of reducing the amount of dephosphorization agent added, the slag forming speed and slag-forming effect are improved, and the iron content in the final slag of the converter and the phosphorus content in the final molten iron are significantly reduced. DETAILED DESCRIPTION
[0050] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:
[0051] Example 1
[0052] This embodiment provides a converter steelmaking dephosphorization agent, the dephosphorization agent comprising, by weight: 7.1 parts of solidified casting slag, 14.07 parts of lime, and 7.22 parts of light burnt material;
[0053] The solidified casting slag is obtained by treating the ladle casting slag with an additive;
[0054] The additives include, by mass percentage, 33.4% magnesium oxide, 15.6% boron oxide, 18.4% silicon oxide, 10% aluminum oxide, and the balance calcium oxide;
[0055] The additive amount is 2% of the mass of the ladle casting slag;
[0056] The particle size of the solidified casting slag is 10-20 mm; the particle size of the lime is 5-7 mm; the light-burned material is light-burned dolomite; the particle size of the light-burned material is 7-9 mm;
[0057] The specific preparation method is as follows:
[0058] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0059] Example 2
[0060] This embodiment provides a converter steelmaking dephosphorization agent, the dephosphorization agent is calculated by weight: 7.7 parts of solidified casting slag, 7.05 parts of lime, and 18.82 parts of light burnt material;
[0061] The solidified casting slag is obtained by treating the ladle casting slag with an additive;
[0062] The additives are calculated by mass percentage as follows: 33% magnesium oxide, 16% boron oxide, 18.6% silicon oxide, 12% aluminum oxide, and the balance is calcium oxide;
[0063] The additive amount is 3% of the mass of the ladle casting slag;
[0064] The particle size of the solidified casting slag is 20-30 mm; the particle size of the lime is 6-9 mm; the light-burned material is light-burned dolomite; the particle size of the light-burned material is 5-10 mm;
[0065] The specific preparation method is as follows:
[0066] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0067] Example 3
[0068] This embodiment provides a converter steelmaking dephosphorization agent, the dephosphorization agent is calculated by weight: 8.3 parts of solidified casting slag, 20.85 parts of lime, and 2.5 parts of light burnt material;
[0069] The solidified casting slag is obtained by treating the ladle casting slag with an additive;
[0070] The additives are calculated by mass percentage as follows: 34% magnesium oxide, 15% boron oxide, 18% silicon oxide, 8% aluminum oxide, and the balance is calcium oxide;
[0071] The additive amount is 4% of the mass of the ladle casting slag;
[0072] The particle size of the solidified casting slag is 10-22 mm; the particle size of the lime is 5-7 mm; the light-burned material is light-burned dolomite; the particle size of the light-burned material is 6-9 mm;
[0073] The specific preparation method is as follows:
[0074] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0075] Example 4
[0076] This embodiment provides a converter steelmaking dephosphorization agent, the dephosphorization agent is calculated by weight: 11.4 parts of solidified casting slag, 8.03 parts of lime, and 7 parts of light burnt material;
[0077] The solidified casting slag is obtained by treating the ladle casting slag with an additive;
[0078] The additives are calculated by mass percentage as follows: 33.6% magnesium oxide, 15.4% boron oxide, 19% silicon oxide, 15% aluminum oxide, and the balance is calcium oxide;
[0079] The additive amount is 2.5% of the mass of the ladle casting slag;
[0080] The particle size of the solidified casting slag is 15-22mm; the particle size of the lime is 5-8mm; the light-burned material is light-burned dolomite; the particle size of the light-burned material is 5-10mm;
[0081] The specific preparation method is as follows:
[0082] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0083] Example 5
[0084] This embodiment provides a converter steelmaking dephosphorization agent, the dephosphorization agent is calculated by weight: 7.4 parts of solidified casting slag, 8.28 parts of lime, and 7.9 parts of light burnt material;
[0085] The solidified casting slag is obtained by treating the ladle casting slag with an additive;
[0086] The additives are calculated by mass percentage as follows: 33.5% magnesium oxide, 15.7% boron oxide, 18.3% silicon oxide, 13% aluminum oxide, and the balance is calcium oxide;
[0087] The additive is added in an amount of 3.4% of the mass of the ladle casting slag;
[0088] The particle size of the solidified casting slag is 15-25 mm; the particle size of the lime is 5-10 mm; the light burnt material includes light burnt dolomite; the particle size of the light burnt material is 5-8 mm;
[0089] The specific preparation method is as follows:
[0090] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0091] Example 6
[0092] This embodiment provides a converter steelmaking dephosphorization agent, wherein the dephosphorization agent is calculated by weight: 7.9 parts of solidified casting slag, 9.85 parts of lime, and 9.35 parts of light burnt material;
[0093] The solidified casting slag is obtained by treating the ladle casting slag with an additive;
[0094] The additives are calculated by mass percentage as follows: 33% magnesium oxide, 15.4% boron oxide, 18.7% silicon oxide, 13% aluminum oxide, and the balance is calcium oxide;
[0095] The additive amount is 2.7% of the mass of the ladle casting slag;
[0096] The particle size of the solidified casting slag is 12-24 mm; the particle size of the lime is 5-10 mm; the light burnt material includes light burnt dolomite; the particle size of the light burnt material is 5-10 mm;
[0097] The specific preparation method is as follows:
[0098] The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
[0099] Application Example 1
[0100] This application example provides a use of the converter steelmaking dephosphorization agent described in Example 1, and the use includes:
[0101] Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag;
[0102] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0103] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 10kg / t steel;
[0104] The dephosphorization time is 6 minutes;
[0105] The final temperature of the molten steel obtained after the dephosphorization treatment is 1630°C.
[0106] The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0107] Application Example 2
[0108] This application example provides a use of the converter steelmaking dephosphorization agent described in Example 2, and the use includes:
[0109] Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag;
[0110] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0111] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 11kg / t steel;
[0112] The dephosphorization time is 7 minutes;
[0113] The final temperature of the molten steel obtained after the dephosphorization treatment is 1650°C.
[0114] The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0115] Application Example 3
[0116] This application example provides a use of the converter steelmaking dephosphorization agent described in Example 3, and the use includes:
[0117] Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag;
[0118] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0119] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 8kg / t steel;
[0120] The dephosphorization time is 6.2 min;
[0121] The final temperature of the molten steel obtained after the dephosphorization treatment is 1650°C.
[0122] The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0123] Application Example 4
[0124] This application example provides a use of the converter steelmaking dephosphorization agent described in Example 4, and the use includes:
[0125] Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag;
[0126] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0127] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 13kg / t steel;
[0128] The dephosphorization time is 6.8min;
[0129] The final temperature of the molten steel obtained after the dephosphorization treatment is 1680°C.
[0130] The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0131] Application Example 5
[0132] This application example provides a use of the converter steelmaking dephosphorization agent described in Example 5, and the use includes:
[0133] Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag;
[0134] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0135] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 13kg / t steel;
[0136] The dephosphorization time is 6.6 min;
[0137] The final temperature of the molten steel obtained after the dephosphorization treatment is 1630°C.
[0138] The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0139] Application Example 6
[0140] This application example provides a use of the converter steelmaking dephosphorization agent described in Example 6, and the use includes:
[0141] Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag;
[0142] The converter steelmaking dephosphorization agent is added into the converter through a high-level silo;
[0143] The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 9kg / t steel;
[0144] The dephosphorization time is 6.4 min;
[0145] The final temperature of the molten steel obtained after the dephosphorization treatment is 1680°C.
[0146] The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0147] Comparative application example 1
[0148] The only difference from Application Example 1 is that the solidified casting slag is replaced by an equal amount of hot casting slag, and the dephosphorizing agent is added directly in batches during dephosphorization. The indicators of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0149] Comparative Application Example 2
[0150] The only difference from Application Example 1 is that the solidified casting slag is replaced with an equal amount of lime. The indicators of the final molten steel and converter final slag obtained are shown in Table 1 and Table 2. In this comparative application example, the amount of lime added was increased by another test, specifically 500 kg, and the indicators of the final molten steel and converter final slag obtained can reach the effect of Application Example 1.
[0151] Comparative Application Example 3
[0152] The only difference from Application Example 1 is that the weight of the solidified casting slag is 20 parts. The indexes of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0153] Comparative Application Example 4
[0154] The only difference from Application Example 1 is that the weight portion of the solidified casting slag is 4. The indexes of the obtained final molten steel and converter final slag are shown in Tables 1 and 2.
[0155] Comparative Application Example 5
[0156] The only difference from Application Example 1 is that the lime is replaced by an equal amount of solidified casting slag. The indices of the final molten steel and converter final slag obtained are shown in Tables 1 and 2.
[0157] Table 1
[0158] Steel Type Slag reduction End point phosphorus content / % Application Example 1 20 Good slag 0.011 Application Example 2 40CR Good slag 0.013 Application Example 3 20 Good slag 0.010 Application Example 4 20 Good slag 0.009 Application Example 5 20 Good slag 0.012 Application Example 6 20 Good slag 0.012 Comparative application example 1 20 Drying 0.016 Comparative Application Example 2 20 Drying 0.012 Comparative Application Example 3 20 Drying 0.014 Comparative Application Example 4 20 Late Splash 0.018 Comparative Application Example 5 20 Late spillage 0.017
[0159] Table 2
[0160]
[0161]
[0162] It can be seen from the results of the above application examples that the converter steelmaking dephosphorization agent provided by the present invention can achieve the target requirements of small slag amount, low oxidizability and low consumption without affecting dephosphorization and production.
[0163] It is stated that the present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.
[0164] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.
[0165] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.
[0166] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.
Claims
1. A converter steelmaking dephosphorization agent, characterized in that: The dephosphorization agent is calculated by weight: 7-12 parts of solidified casting slag, 7-21 parts of lime, and 2-19 parts of light burnt material; The solidified casting slag comprises, by mass percentage, 50-54% CaO, 24-26% Al2O3, 5-6% MgO, 8-9% SiO2, 0.06-0.08% V2O5, 0.3-0.4% MnO, 1.1-1.2% S and 0.7-0.8% TFe, the total being 100%, of which 0.4-0.5% FeO; The light-burned material is light-burned dolomite.
2. The converter steelmaking dephosphorization agent according to claim 1, characterized in that: The solidified casting slag is obtained by treating the ladle casting slag with an auxiliary agent.
3. The converter steelmaking dephosphorization agent as claimed in claim 2, characterized in that: The additives include, by mass percentage, 33-34% magnesium oxide, 15-16% boron oxide, 18-19% silicon oxide, 8-15% aluminum oxide, and the balance calcium oxide.
4. The converter steelmaking dephosphorization agent as claimed in claim 2, characterized in that: The additive is added in an amount of 2-4% of the mass of the ladle casting slag.
5. The converter steelmaking dephosphorization agent according to claim 1, characterized in that: The particle size of the solidified casting slag is 10-30 mm.
6. The converter steelmaking dephosphorization agent according to claim 1, characterized in that: The particle size of the lime is 5-10 mm.
7. The converter steelmaking dephosphorization agent according to claim 1, characterized in that: The particle size of the light burning material is 5-10 mm.
8. A method for preparing a converter steelmaking dephosphorization agent as claimed in any one of claims 1 to 7, characterized in that: The preparation method comprises: The ladle casting slag is treated with an auxiliary agent to obtain solidified casting slag, and then the solidified casting slag, lime and light burnt material are mixed according to a formula to obtain a converter steelmaking dephosphorization agent.
9. A use of the converter steelmaking dephosphorization agent as claimed in any one of claims 1 to 7, characterized in that: The use includes dephosphorizing molten iron using the converter steelmaking dephosphorization agent, specifically including: The converter steelmaking dephosphorization agent is added into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag.
10. The use according to claim 9, characterized in that The converter steelmaking dephosphorization agent is added into the converter through a high-level silo.
11. The use according to claim 9, characterized in that The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 8-13 kg / t steel.
12. The use according to claim 9, characterized in that: The dephosphorization treatment time is 6-7 minutes.
13. The use according to claim 9, characterized in that The terminal temperature of the molten steel obtained after the dephosphorization treatment is ≥1630°C.
14. The use according to claim 9, characterized in that The uses include: Adding the converter steelmaking dephosphorization agent into the converter to dephosphorize the molten steel to obtain final molten steel and converter final slag; The converter steelmaking dephosphorization agent is added into the converter through a high-level silo; The addition amount of the converter steelmaking dephosphorizing agent in the dephosphorization treatment is 8-13 kg / t steel; The dephosphorization time is 6-7min; The terminal temperature of the molten steel obtained after the dephosphorization treatment is ≥1630°C.