A chromium-containing high-speed desulfurization and inclusion-removing slag lotion and its preparation method

Abstract

The present invention discloses a chromium-containing high-speed desulfurization and inclusion removal slag lotion and its preparation method, which relates to the field of iron and steel metallurgy. The chromium-containing slag or a mixture of a chromium-containing material and an alumina-containing material is reacted in a high-temperature oxygen-containing environment to obtain a chromium-containing slag lotion. 3+ Corundum solid solution, containing Cr 3+ A chromium-containing high-speed desulfurization and inclusion removal slag detergent is prepared by grinding, screening, and mixing a corundum solid solution, a CaO-containing material, and a SiO2-containing material. This chromium-containing high-speed desulfurization and inclusion removal slag detergent is used in the steelmaking process to not only recycle chromium slag resources and enhance environmental protection, but also effectively and quickly remove sulfur and other impurities from molten steel, optimizing steel quality, shortening refining time, improving steelmaking efficiency, and reducing costs.

Description

Technical Field

[0001] The present invention relates to the field of iron and steel metallurgy, and in particular to a chromium-containing high-speed desulfurization and inclusion-removing slag lotion and a preparation method thereof. Background Art

[0002] During the steelmaking process, slag washers remove impurities such as sulfur and phosphorus from molten steel through the synergistic effects of physical adsorption of aggregated slag, chemical reaction decontamination, and slag property regulation. They adjust the slag's alkalinity and viscosity to facilitate separation from the molten steel, prevent oxidation of the molten steel in contact with air, and reduce heat loss, thereby removing impurities and protecting the molten steel. Common slag washers are generally composed of CaO, MgO, Al2O3, and SiO2, with SiO2 primarily used as a flux in acidic steelmaking processes.

[0003] Chromium slag is a solid waste produced from the production of metallic chromium and other products, with an output of 60,000 to 80,000 tons per year. Due to the backwardness of science and technology, a large amount of chromium slag solid waste has not been recycled and treated in a timely and effective manner, causing environmental problems such as soil and water pollution. The main components of chromium slag are Al2O3 and Cr2O3. Chromium is present in the form of Cr 3+ The crystal structure of corundum (α-Al2O3) is hexagonal close-packed. 3+ Can replace Al by ion replacement 3+ Enter the crystal lattice and form a solid solution.

[0004] Based on this, how to apply chromium slag solid waste in the preparation process of slag detergent to achieve the goals of waste recycling and optimizing steel performance is of practical significance. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a chromium-containing high-speed desulfurization and inclusion-removing slag lotion and a preparation method thereof.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A chromium-containing high-speed desulfurization and inclusion-removing slag lotion, the preparation of which comprises the following steps:

[0008] Step S1: crush the chromium slag, stir it for 20-25 minutes, and then pass it through a 50-70 mesh sieve to obtain a mixture containing Al2O3 and Cr2O3. Keep the mixture at 1200-1300℃ for 3-5 hours to obtain Cr2O3. 3+ Corundum solid solution;

[0009] Furthermore, the chromium slag in step S1 is selected from one of the slag produced by the production of metallic chromium and the slag produced by the production of chromium alloys. The chromium slag can also be replaced by a mixture of a chromium-containing material and an alumina-containing material in a mass ratio of 60-80 g:12-20 g; the chromium-containing material is selected from one of chromium slag, chromium trioxide, metallic chromium, and a chromium-containing alloy; and the alumina-containing material is selected from one of corundum and high-alumina bauxite.

[0010] During the reaction process of step S1, Al2O3 in the chromium slag is converted into the crystal structure of corundum (α-Al2O3) under high temperature conditions, and the Cr in the chromium slag is converted into the crystal structure of corundum (α-Al2O3). 3+ Can replace Al by ion replacement 3+ Entering the lattice, forming Cr-containing 3+ When chromium slag is replaced by chromium-containing materials and mixed with alumina-containing materials, the Cr in chromium slag, chromium trioxide, metallic chromium or chromium-containing alloy (converted to Cr2O3 under high temperature oxygen-containing conditions) 3+ Can replace Al by ion replacement 3+ Entering the lattice, forming Cr-containing 3+ Corundum solid solution;

[0011] Step S2: 3+ The corundum solid solution, CaO-containing material and SiO2-containing material were crushed and passed through a 4-6 mesh sieve to obtain the Cr-containing 3+ Corundum powder, CaO powder and SiO2 powder, Cr 3+ The corundum powder, CaO-containing powder and SiO2-containing powder are mixed and stirred for 2-2.5 hours, then pelletized, and then dried at 150-250°C for 24-25 hours to obtain a chromium-containing high-speed desulfurization and inclusion-removing slag lotion;

[0012] Furthermore, the CaO-containing material is selected from one of limestone and quicklime, the SiO2-containing material is selected from one of silica and wollastonite, and the Cr-containing material is selected from one of limestone and quicklime. 3+ The ratio of corundum powder, CaO-containing powder and SiO2-containing powder is 70-90g:13-15g:10-12g; the size of the pressed balls is 15-40mm; the Al2O3 content of the chromium-containing high-speed desulfurization and inclusion removal slag lotion is 60-80%, the CaO content is 10-15%, the SiO2 content is 8-10%, and the Cr2O3 content is 5-7%;

[0013] Beneficial effects of the present invention:

[0014] 1. The present invention provides a chromium-containing high-speed desulfurization and inclusion-removing slag lotion and a preparation method thereof. The preparation process of the chromium-containing high-speed desulfurization and inclusion-removing slag lotion achieves high-value and efficient utilization of chromium slag, greatly reducing environmental pollution and improving the secondary utilization rate of chromium resources.

[0015] 2. The present invention heats chromium slag (or chromium-containing material and alumina-containing material) at high temperature to produce Cr 3+ Can replace Al by ion replacement 3+ Entering the lattice, forming Cr-containing 3+ The corundum solid solution structure improves the reactivity of alumina, enabling the slag detergent to remove harmful substances such as sulfides more quickly, thereby purifying molten steel, saving refining time, and effectively promoting energy conservation and carbon reduction in the steelmaking process.

[0016] 3. During the use of slag detergent in steelmaking, Cr 3+ It will be reduced to metallic chromium by the molten steel and evenly dispersed in the molten steel, improving the corrosion resistance, strength and hardness of the steel, thereby optimizing the quality of the steel. DETAILED DESCRIPTION

[0017] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0018] The composition table of the slag produced by producing metallic chromium used in the embodiment is as follows:

[0019]

[0020] Example 1

[0021] A chromium-containing high-speed desulfurization and inclusion-removing slag lotion, the preparation of which comprises the following steps:

[0022] Step S1: crush the slag produced by the production of metallic chromium, stir it for 20 minutes, and then pass it through a 50-mesh sieve to obtain a mixture containing Al2O3 and Cr2O3. The mixture is kept at 1200°C for 3 hours to obtain a Cr-containing 3+ Corundum solid solution;

[0023] Step S2: 3+ The corundum solid solution, CaO-containing material and SiO2-containing material were crushed and passed through a 4-mesh sieve to obtain the Cr-containing 3+ Corundum powder, CaO powder and SiO2 powder, Cr 3+ The corundum powder, CaO-containing powder and SiO2-containing powder were mixed and stirred for 2 hours, then pelletized and dried at 200℃ for 24 hours to obtain a chromium-containing high-speed desulfurization and inclusion-removing slag lotion; the CaO-containing material was limestone (supplier: Zhengbing Lime Factory, Baligangou, Dongbao District, Jingmen City), the SiO2-containing material was silica (supplier: Lingshou County Hengshuo Mineral Products Co., Ltd.), and the Cr-containing3+ The usage ratio of corundum powder, CaO-containing powder and SiO2-containing powder is 70g:13g:10g; the size of the pressed ball is 20mm; the Al2O3 content in the chromium-containing high-speed desulfurization and inclusion removal slag lotion is 64%, the CaO content is 10%, the SiO2 content is 8% and the Cr2O3 content is 5%.

[0024] The prepared chromium-containing high-speed desulfurization and inclusion removal slag detergent is applied to the refining process of a steel plant, with a desulfurization rate of 91%. The slag has moderate viscosity and strong adsorption capacity, which can effectively adsorb inclusions in molten steel and significantly improve the quality of steel. The slag has a fast slagging speed, which can effectively shorten the refining time by 6 minutes. The steelmaking efficiency is high and the cost is low.

[0025] Example 2

[0026] A chromium-containing high-speed desulfurization and inclusion-removing slag lotion, the preparation of which comprises the following steps:

[0027] Step S1: crush the slag and corundum produced by the production of metallic chromium, stir for 23 minutes, and then pass through a 60-mesh sieve to obtain a mixture containing Al2O3 and Cr2O3. The mixture is kept at 1200°C for 3.3 hours to obtain a mixture containing Cr. 3+ The mass ratio of slag produced by the production of metallic chromium to corundum is 60g:12g;

[0028] Step S2: 3+ The corundum solid solution, CaO-containing material and SiO2-containing material were crushed and passed through a 5-mesh sieve to obtain the Cr-containing 3+ Corundum powder, CaO powder and SiO2 powder, Cr 3+ The corundum powder, CaO-containing powder and SiO2-containing powder were mixed and stirred for 2.3 hours, then pelletized and dried at 200℃ for 24 hours to obtain a chromium-containing high-speed desulfurization and inclusion-removing slag lotion; the CaO-containing material was limestone (supplier: Zhengbing Lime Factory, Baligangou, Dongbao District, Jingmen City), the SiO2-containing material was silica (supplier: Lingshou County Hengshuo Mineral Products Co., Ltd.), and the Cr-containing 3+ The usage ratio of corundum powder, CaO-containing powder and SiO2-containing powder is 80g:14g:11g; the size of the pressed ball is 20mm; the Al2O3 content in the chromium-containing high-speed desulfurization and inclusion removal slag lotion is 74%, the CaO content is 11%, the SiO2 content is 8% and the Cr2O3 content is 5%.

[0029] The prepared chromium-containing high-speed desulfurization and inclusion removal slag detergent is applied to the refining process of a steel plant, with a desulfurization rate of 96%. The slag has moderate viscosity and strong adsorption capacity, which can effectively adsorb inclusions in molten steel and significantly improve the quality of steel. The slag has a fast slagging speed, which can effectively shorten the refining time by 10 minutes. The steelmaking efficiency is high and the cost is low.

[0030] Example 3

[0031] A chromium-containing high-speed desulfurization and inclusion-removing slag lotion, the preparation of which comprises the following steps:

[0032] Step S1: crush the slag produced by the production of metallic chromium, stir it for 25 minutes, and then pass it through a 70-mesh sieve to obtain a mixture containing Al2O3 and Cr2O3. The mixture is kept at 1200°C for 5 hours to obtain a Cr-containing 3+ Corundum solid solution;

[0033] Step S2: 3+ The corundum solid solution, CaO-containing material and SiO2-containing material were crushed and passed through a 6-mesh sieve to obtain the Cr-containing 3+ Corundum powder, CaO powder and SiO2 powder, Cr 3+ The corundum powder, CaO-containing powder and SiO2-containing powder were mixed and stirred for 2.5 hours, then pelletized and dried at 200℃ for 25 hours to obtain a chromium-containing high-speed desulfurization and inclusion-removing slag lotion; the CaO-containing material was limestone (supplier: Zhengbing Lime Factory, Baligangou, Dongbao District, Jingmen City), the SiO2-containing material was silica (supplier: Lingshou County Hengshuo Mineral Products Co., Ltd.), and the Cr-containing 3+ The usage ratio of corundum powder, CaO-containing powder and SiO2-containing powder is 90g:15g:12g; the size of the pressed ball is 20mm; the Al2O3 content in the chromium-containing high-speed desulfurization and inclusion removal slag lotion is 68%, the CaO content is 11%, the SiO2 content is 8% and the Cr2O3 content is 5%.

[0034] The prepared chromium-containing high-speed desulfurization and inclusion removal slag detergent is applied to the refining process of a steel plant, with a desulfurization rate of 92%. The slag has moderate viscosity and strong adsorption capacity, which can effectively adsorb inclusions in molten steel and significantly improve the quality of steel. The slag has a fast slagging speed, which can effectively shorten the refining time by 8 minutes. The steelmaking efficiency is high and the cost is low.

[0035] The above content is merely an example and explanation of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion, characterized in that: The steps include: Step S1: crush the chromium slag, stir it and then sieve it to obtain a mixture containing Al2O3 and Cr2O3, and heat the mixture at high temperature to obtain a mixture containing Cr2O3. 3+ Corundum solid solution; Step S2: 3+ The corundum solid solution, CaO-containing material and SiO2-containing material were crushed and sieved to obtain Cr-containing 3+ Corundum powder, CaO powder and SiO2 powder, Cr 3+ The corundum powder, CaO-containing powder and SiO2-containing powder are mixed and stirred, then pelletized and dried to obtain a chromium-containing high-speed desulfurization and inclusion-removing slag lotion.

2. The method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion according to claim 1, characterized in that: The chromium slag in step S1 is selected from one of the slag produced in the production of metallic chromium and the slag produced in the production of chromium alloy, and is sieved with a mesh size of 50-70 meshes.

3. The method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion according to claim 1, characterized in that: The chromium slag in step S1 may also be replaced by a mixture of a chromium-containing material and an alumina-containing material in a mass ratio of 60-80 g:12-20 g.

4. The method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion according to claim 3, characterized in that: The chromium-containing material is selected from one of chromium slag, chromium trioxide, metallic chromium, and chromium-containing alloy; the aluminum oxide-containing material is selected from one of corundum and high-alumina bauxite.

5. The method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion according to claim 1, characterized in that: In step S2, the CaO-containing material is selected from one of limestone and quicklime, and the SiO2-containing material is selected from one of silica and wollastonite.

6. The method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion according to claim 1, characterized in that: The mesh size of the sieve in step S2 is 4-6 mesh, and the size of the pressed balls is 15-40 mm.

7. The method for preparing a chromium-containing high-speed desulfurization and inclusion-removing slag lotion according to claim 1, characterized in that: Step S2 contains Cr 3+ The usage ratio of corundum powder, CaO-containing powder and SiO2-containing powder is 70-90g:13-15g:10-12g.

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