A vanadium extraction coolant and its application in reducing the total iron content of vanadium slag in converter

Abstract

The invention discloses a vanadium extraction coolant and its application in reducing the total iron content of vanadium slag in a converter. The invention originally proposes a new method for effectively reducing the total iron content in vanadium slag by adding a self-made vanadium extraction coolant with a high calcium oxide content during the vanadium extraction process; and in the process of preparing the vanadium extraction coolant with a high calcium oxide content, the invention fully utilizes the characteristics of the existing steelmaking converter enrichment sludge containing a high calcium oxide content and a high total iron content, and introduces it into the preparation process of the vanadium extraction coolant in an appropriate amount, which can not only make full use of waste resources, reduce environmental pollution, and increase steel production; but also effectively control the calcium oxide content in the prepared vanadium extraction coolant within a reasonable range, thereby realizing accurate control of the calcium oxide content in the vanadium slag, thereby realizing effective reduction of the total iron content in the vanadium slag without affecting the vanadium product yield in the subsequent process treatment of the vanadium slag.

Description

Technical Field

[0001] The invention relates to the technical field of iron and steel metallurgy, in particular to a vanadium extraction coolant and application thereof in reducing the total iron content of vanadium slag extracted from a converter. Background Art

[0002] The existing converter vanadium extraction process generally has the problem of high total iron content in vanadium slag, which is even as high as 35% to 40%, which will lead to high steel consumption in the vanadium extraction process and increased vanadium slag treatment costs. Therefore, it is urgent to find ways to reduce the total iron content in vanadium slag to reduce the consumption of steel in the converter vanadium extraction process, thereby reducing the production cost of vanadium extraction and effectively improving the grade of vanadium pentoxide in vanadium slag, making it more conducive to the production of vanadium products in subsequent processes. Summary of the invention

[0003] The purpose of the present invention is to originally propose a method of adding a self-made vanadium extraction coolant with a high calcium oxide content during the vanadium extraction process, thereby effectively reducing the total iron content in the vanadium slag.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A vanadium extraction coolant, wherein the raw materials for preparing the vanadium extraction coolant include:

[0006] 55-65% iron oxide scale, 15-20% steelmaking converter enriched sludge, 15-22% vanadium extraction sludge and 5% binder; among which,

[0007] The mass percentage of each component in the iron oxide scale is: TFe 63-70%, and the rest is oxygen and impurities;

[0008] The mass percentages of the components in the steelmaking converter enriched sludge include: TFe 55% to 65%; CaO 5 to 15%; SiO 2 3% to 7%;

[0009] The mass percentages of the components in the vanadium extraction sludge include: TFe 58% to 65%; CaO 0.6% to 1.2%; SiO 25% to 10%;

[0010] The mass percentage of each component in the binder is: SiO2 90-95%, and the rest is impurities.

[0011] As a further improvement of the present invention, the mass percentages of the components in the vanadium extraction coolant include:

[0012] TFe58%~65%; CaO1.2%~1.5%; SiO26%~9%.

[0013] The present invention also provides a method for reducing the total iron content of vanadium slag in a converter by using the aforementioned vanadium extraction coolant, the method comprising:

[0014] In the process of vanadium extraction in the converter, the aforementioned vanadium extraction coolant is added at a unit consumption of 25-35 kg / t, and vanadium slag is obtained through the vanadium extraction process.

[0015] As a further improvement of the present invention, the mass percentages of the components in the vanadium slag include:

[0016] CaO2.2%~2.5%; V2O515%~18%; TFe25%~28%; SiO213.5%~16%.

[0017] As a further improvement of the present invention, the mass percentages of the components in the molten iron used in the converter vanadium extraction process include:

[0018] C4.0%~4.5%; Si0.07%~0.3%; Mn0.10%~0.3%; P0.06%~0.15%; S0.05%~0.15%; V0.29%~0.35%; Ti0.10%~0.25%; the balance is Fe.

[0019] Technical effects and advantages of the present invention:

[0020] The present invention originally proposes a new method for effectively reducing the total iron content in vanadium slag by adding a self-made vanadium extraction coolant with a high calcium oxide content during the vanadium extraction process; and in the process of preparing the vanadium extraction coolant with a high calcium oxide content, the present invention fully utilizes the characteristics of the existing steelmaking converter enrichment sludge containing a high calcium oxide content and a high total iron content, and introduces it into the preparation process of the vanadium extraction coolant in an appropriate amount, which can not only make full use of waste resources, reduce environmental pollution, and increase steel production; but also effectively control the calcium oxide content in the prepared vanadium extraction coolant within a reasonable range, thereby realizing precise control of the calcium oxide content in the vanadium slag, thereby achieving effective reduction of the total iron content in the vanadium slag without affecting the vanadium product yield in the subsequent process treatment of the vanadium slag.

[0021] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a curve chart showing the relationship between the total iron content and the calcium oxide content in vanadium slag. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In order to solve the problem of high total iron content in vanadium slag commonly existing in the existing converter vanadium extraction process, the present invention originally proposes a method of adding a self-made vanadium extraction coolant with a high calcium oxide content during the vanadium extraction process, thereby achieving an effective reduction in the total iron content in the vanadium slag; and in the process of preparing a vanadium extraction coolant with a high calcium oxide content, the present application fully utilizes the characteristics of the existing steelmaking converter enrichment sludge containing a high calcium oxide content and a high total iron content, and introduces it into the preparation process of the vanadium extraction coolant in an appropriate amount, which can not only make full use of waste resources, reduce environmental pollution, and increase steel production; but also effectively control the calcium oxide content in the prepared vanadium extraction coolant within a reasonable range, thereby achieving an effective reduction in the total iron content in the vanadium slag without affecting the vanadium product yield in the subsequent process of the vanadium slag. The specific technical scheme is now introduced as follows:

[0025] In the practice of vanadium extraction in converters, technicians creatively discovered that the total iron content of vanadium slag is negatively correlated with the calcium oxide content, as shown below: Figure 1 The relationship curve between the total iron content and the calcium oxide content in the vanadium slag is shown in (unit: %). The higher the calcium oxide content, the lower the total iron content in the vanadium slag. And further, according to the detailed analysis of the vanadium slag composition data, it is found that with the increase of calcium oxide content, when calcium oxide is greater than 2.2%, the total iron content in the vanadium slag drops from the original 29-32% to below 28%, achieving at least a 1-2 percentage point reduction in the total iron content in the vanadium slag. This effectively reduces the consumption of steel materials in the converter vanadium extraction process and achieves a significant reduction in the production cost of vanadium extraction.

[0026] Furthermore, the present invention increases the calcium oxide content in the vanadium extraction coolant by using enriched sludge with a high calcium oxide content, so that the calcium oxide content in the vanadium slag reaches 2.2-2.5%, thereby reducing the total iron content in the vanadium slag, which is beneficial to reducing the iron loss of converter vanadium extraction and reducing the production cost of vanadium extraction. However, if the calcium oxide content in the vanadium slag is too high, if it exceeds 2.50%, it will affect the vanadium recovery rate of the vanadium slag in the subsequent process treatment. Therefore, the key to the present invention is to control the calcium oxide content in the vanadium extraction coolant to 1.2-1.5%, and then control the calcium oxide content in the vanadium slag to 2.2-2.5%, so as to reduce the total iron content of the vanadium slag without affecting the recovery rate of the vanadium product in the subsequent process treatment.

[0027] Furthermore, in order to prepare a vanadium extraction coolant that meets the calcium oxide content requirements, the present application uses steelmaking converter enriched sludge containing a high calcium oxide content and a high total iron content to prepare the vanadium extraction coolant. The specific composition of the steelmaking converter enriched sludge used includes: by mass fraction, TFe 55% to 65%; CaO 5 to 15%; SiO 2 3% to 7%.

[0028] Furthermore, the raw material ratio for preparing the vanadium-extracting coolant is as follows: 55-65% of iron oxide scale, 15-20% of steelmaking converter enriched sludge, 15-22% of vanadium-extracting sludge and 5% of binder. The mass percentage of each component in the vanadium-extracting coolant thus prepared is preferably controlled at: TFe 58%-65%; CaO 1.2%-1.5%; SiO2 6%-9%.

[0029] Furthermore, the present invention also provides a method for reducing the total iron content of vanadium slag in a converter by utilizing the vanadium extraction coolant prepared above. The method comprises adding the vanadium extraction coolant with a high calcium oxide content into the vanadium extraction converter at a unit consumption of 25 to 35 kg / t during vanadium extraction in the converter, and then obtaining vanadium slag with a high calcium oxide content and a low total iron content through a vanadium extraction process.

[0030] Furthermore, the mass percentages of the components in the prepared vanadium slag include: CaO 2.2% to 2.5%; V2O5 15% to 18%; TFe 25% to 28%; SiO2 13.5% to 16%.

[0031] Specifically, the mass percentages of the components in the molten iron used in the converter vanadium extraction process include:

[0032] C4.0%~4.5%; Si0.07%~0.3%; Mn0.10%~0.3%; P0.06%~0.15%; S0.05%~0.15%; V0.29%~0.35%; Ti0.10%~0.25%; the balance is Fe.

[0033] The method for reducing the total iron content of vanadium slag in a converter provided by the present invention is described in detail below in conjunction with specific embodiments and comparative examples:

[0034] Example

[0035] A steel plant uses steelmaking converter enriched sludge with a mass percentage of TFe61.2%, CaO7.2%, and SiO24.95%. The raw material ratio for producing vanadium-extracting coolant is as follows: 60% iron oxide scale, 17% enriched sludge, 18% vanadium-extracting sludge, and 5% binder. Among them, the mass percentage of each component in the iron oxide scale is: TFe65%, and the rest is oxygen and impurities; the mass percentage of each component in the vanadium-extracting sludge is: TFe60%; CaO0.8%; SiO27%, and the rest is impurities; the mass percentage of each component in the binder is: SiO293%, and the rest is impurities. The mass percentage of the produced vanadium-extracting coolant is: TFe60.2%, CaO1.37%, SiO26.75%, and the rest is impurities. 120 tons of vanadium extraction converter, add 140 tons of molten iron, the mass percentage of molten iron is: C4.25%, Si0.18%, Mn0.20%, P0.076%, S0.087%, V0.302%, Ti0.23%, the balance is Fe. Add 4.2 tons of vanadium extraction coolant, coolant consumption is 30.0kg / t, oxygen lance flow rate is 18000m 3 / h, oxygen blowing time 5 minutes and 40 seconds, the mass percentage of vanadium slag produced is: CaO 2.41%, V2O5 16.5%, TFe 27.56%, SiO2 14.43%.

[0036] Comparative Example

[0037] Comparison of furnaces: The raw material ratio of vanadium extracting coolant is: 65% iron scale, 5% binder, 30% vanadium extracting sludge; among them, the mass percentage of each component in the iron scale is: TFe66.3%, the rest is oxygen and impurities; the mass percentage of each component in the vanadium extracting sludge is: TFe60.6%; CaO1.2%; SiO27.82%, the rest is impurities; the mass percentage of each component in the binder is: SiO293.0%. %, the rest is impurities. The composition of the vanadium extracting coolant is: TFe61.3%, CaO0.36%, SiO27.0%. 120 tons of vanadium extracting converter, add 140 tons of molten iron, the mass percentage of molten iron is: C4.31%, Si0.15%, Mn0.20%, P0.078%, S0.085%, V0.302%, Ti0.21%, the rest is Fe. 4.25 tons of vanadium extraction coolant was added, the coolant consumption was 30.36 kg / t, and the oxygen lance flow rate was 18000 m 3 / h, oxygen blowing time 5 minutes and 15 seconds, the mass percentage of vanadium slag produced: CaO 1.85%, V2O5 16.3%, TFe 31.2%, SiO2 14.66%.

[0038] From the comparison results of the above embodiments and comparative examples, it can be seen that since about 17% of steelmaking converter enriched sludge was added when preparing the vanadium extraction coolant, the calcium oxide content in the coolant increased from 0.36% to 1.37%; then due to the slight increase in the calcium oxide content in the coolant, the calcium oxide content in the vanadium slag obtained by vanadium extraction also increased from 1.85% to 2.41%, and the total iron content was also reduced from 31.2% to 27.56%, thereby reducing the total iron content of the vanadium slag obtained by converter vanadium extraction.

[0039] In summary, the vanadium extraction coolant provided by the present invention and its application in reducing the total iron content of vanadium slag in converter vanadium extraction, originally proposed a new method for effectively reducing the total iron content in vanadium slag by adding a self-made vanadium extraction coolant with a high calcium oxide content during the vanadium extraction process; and in the process of preparing the vanadium extraction coolant with a high calcium oxide content, the present invention fully utilizes the characteristics of the existing steelmaking converter enriched sludge containing a high calcium oxide content and a high total iron content, and introduces it into the preparation process of the vanadium extraction coolant in an appropriate amount, which can not only make full use of waste resources, reduce environmental pollution, and increase steel production; but also can effectively control the calcium oxide content in the prepared vanadium extraction coolant within a reasonable range, thereby realizing precise control of the calcium oxide content in the vanadium slag, thereby achieving effective reduction of the total iron content in the vanadium slag without affecting the vanadium product yield in the subsequent process treatment of the vanadium slag.

[0040] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A vanadium extraction coolant, characterized in that: The raw materials for preparing the vanadium extraction coolant include: 55-65% iron oxide scale, 15-20% steelmaking converter enriched sludge, 15-22% vanadium extraction sludge and 5% binder; among which, The mass percentage of each component in the iron oxide scale is: TFe 63-70%, and the rest is oxygen and impurities; The mass percentages of the components in the steelmaking converter enriched sludge include: TFe 55% to 65%; CaO 5 to 15%; SiO2 3% to 7%; The mass percentages of the components in the vanadium extraction sludge include: TFe 58% to 65%; CaO 0.6 to 1.2%; SiO2 5% to 10%; The mass percentage of each component in the binder is: SiO2 90-95%, and the rest is impurities; The mass percentages of the components in the vanadium extraction coolant include: TFe 58%~65%; CaO 1.2%~1.5%; SiO2 6%~9%, and the rest are impurities.

2. A method for reducing the total iron content of converter vanadium slag using the vanadium extraction coolant according to claim 1, characterized in that: The method comprises: In the process of vanadium extraction in the converter, the aforementioned vanadium extraction coolant is added at a unit consumption of 25-35 kg / t, and vanadium slag is obtained through the vanadium extraction process.

3. The method for reducing the total iron content of vanadium slag in a converter according to claim 2, characterized in that: The mass percentages of the components in the vanadium slag include: CaO 2.2% ~ 2.5%; V2O5 15% ~ 18%; TFe 25% ~ 28%; SiO2 13.5% ~ 16%.

4. The method for reducing the total iron content of vanadium slag in a converter according to claim 2, characterized in that: The mass percentages of the components in the molten iron used in the converter vanadium extraction process include: C 4.0%~4.5%; Si 0.07%~0.3%; Mn 0.10%~0.3%; P 0.06%~0.15%; S 0.05%~0.15%; V 0.29%~0.35%; Ti 0.10%~0.25%; the balance is Fe.

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