Mineral admixture prepared from converter slag and production method of mineral admixture

Abstract

The invention discloses a mineral admixture prepared from converter slag, which is prepared from the following raw materials in percentage by weight: 10-13% of SiO2, 35-45% of CaO, 1-3% of Al2O3, 5-8% of Fe2O3 and 8-12% of MgO, and the converter slag is finely ground and then mixed with slag, desulfurized gypsum, water and waste rock sand according to the ratio of 1: 4: 1: 10. According to the performance requirements, sulfur trioxide is larger than or equal to 5.0% and smaller than 12.0%, the chlorine ion content is smaller than or equal to 0.06%, the density is larger than or equal to 2.8 g / m < 3 >, the fineness is that screen residues of a 45-micron square hole sieve are smaller than or equal to 10.0%, the initial setting time is larger than or equal to 60 min, and the final setting time is smaller than or equal to 600 min. The method has the advantages that the converter steel slag can be fully recycled, and the manufactured mineral admixture is good in chemical performance, wide in application range and high in practicability.

Description

Technical Field

[0001] The invention belongs to the technical field of iron and steel metallurgy, and in particular relates to a mineral admixture made from converter slag and a production method thereof. Background Art

[0002] Converter slag is a by-product of steel smelting in steel plants, accounting for about 30% to 40% of steel production. In recent years, with the rapid development of my country's steel industry, the amount of steel slag produced has also increased year by year. After water quenching, the main mineral composition is silicon-aluminum glass, which has good potential hydraulic hardness and can be ground into concrete admixtures. The comprehensive utilization rate of steel slag is about 22%. The main mineral composition is overburned tricalcium silicate and dicalcium silicate, olivine, rhodonite, RO phase, etc. The main uses are road materials, engineering backfill materials, building materials, and ground into cement admixtures and concrete admixtures. The preparation of steel slag powder can also help steel plants solve the environmental pressure of "zero emission" of steel slag. At present, converter slag is usually discharged directly, which undoubtedly increases the pollution to the environment. Some companies will reuse converter slag, but the utilization rate is always low, and the physical and chemical properties of the mineral admixtures produced are not high, and the use effect is not good. Summary of the invention

[0003] The purpose of the present invention is to solve the problems of low utilization rate of existing converter slag and poor performance of mineral admixtures, and to provide a method for manufacturing mineral admixtures using converter slag, which can fully recycle converter slag, and the manufactured mineral admixture has good physicochemical properties, a wide range of applications, and strong practicality.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A converter slag manufacturing mineral admixture, the converter slag raw materials and their percentages include: SiO2: 10-13%, CaO: 35-45%, Al2O3: 1-3%, Fe2O3: 5-8%, MgO: 8-12%, and the converter slag is finely ground and mixed with slag, desulfurized gypsum, water, and waste sand in a ratio of 1:4:1:10. Its performance requirements are as follows: 5.0% ≤ sulfur trioxide <12.0%, chloride ion content ≤0.06%, density ≥2.8 g / m 3 The fineness is 45μm square hole sieve residue ≤10.0%, initial setting time ≥60min, final setting time ≤600min, which meets the requirements of compressive strength and flexural strength and realizes batch production.

[0005] Furthermore, the performance requirements of the mineral admixture include: sulfur trioxide: 5.0-11.99%, chloride ion content ≤ 0.06%, density ≥ 2.8 g / m 3 ; Fineness, i.e., the residue on 45μm square hole sieve is ≤10.0%, initial setting time is ≥60min, and final setting time is ≤600min.

[0006] Furthermore, the performance requirements of the mineral admixture include: sulfur trioxide: 6.0-11.0%, chloride ion content ≤ 0.05%, density ≥ 2.9 g / m 3 ; Fineness, i.e., the residue on 45μm square hole sieve is ≤9.0%, initial setting time is ≥70min, and final setting time is ≤500min.

[0007] In order to further achieve the purpose of the present invention, a production method for manufacturing mineral admixtures from converter slag is also provided, and the specific steps are as follows, including: (1) Lime is used to desulfurize the molten iron before it enters the furnace, and then the slag is removed after desulfurization. The slag is then recovered; (2) After the converter is finished tapping, slag splashing and furnace protection operation is carried out. After slag splashing, the slag is introduced into the slag spray for recovery; (3) The recovered desulfurization slag and converter slag are transported to the slag treatment workshop for slag stewing operation, and the stewing time is 3 to 5 days; (4) The slag after slagging is pulverized and mixed with slag, desulfurized gypsum, water, and waste sand in a ratio of 1:4:1:10; (5) The stirring temperature is 0-50°C, and cementitious materials are added to prepare mineral admixtures.

[0008] Compared with the prior art, the technical solution of the present invention has the following advantages: (1) The present invention obtains refined mineral admixture raw materials by simmering and grinding converter slag, which effectively reduces the pollution of converter slag to the environment, realizes green and clean production in the steel industry, and improves the image of the enterprise; (2) After strength and toughness tests, the physical and chemical properties of the mineral admixture of the present invention have reached the requirements of equivalent cement, and mass production has been achieved. The product is highly practical and the supply performance continues to improve; (3) The present invention pulverizes the slag and mixes it with slag, desulfurized gypsum, water, and waste sand in a ratio of 1:4:1:10. This is obtained through continuous practice verification and has a unique formula usage right. The formula can be used by other enterprises and has product versatility. DETAILED DESCRIPTION Example

[0009] In order to make the present invention more clear, the following further describes a method for producing a mineral admixture using converter slag of the present invention. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0010] The raw materials of converter slag for manufacturing mineral admixture from converter slag are: SiO2: 10-13%, CaO: 35-45%, Al2O3: 1-3%, Fe2O3: 5-8%, and MgO: 8-12%.

[0011] A production method for producing mineral admixtures from converter slag, characterized in that: S1. Before the molten iron enters the furnace, it is desulfurized with lime, and then slag is removed after desulfurization. After slag removal, the slag is recovered; S2. After the converter is finished tapping, slag splashing and furnace protection operation is performed. After slag splashing, the slag is introduced into the slag spray for recovery; S3. The recovered desulfurization slag and converter slag are transported to the slag treatment workshop for slag stewing operation, and the stewing time is 3 to 5 days; S4, the slag after slagging is pulverized and mixed with slag, desulfurized gypsum, water, and waste sand in a ratio of 1:4:1:10; S5. The stirring temperature is 0-50°C, and cementitious materials are added at the same time to prepare mineral admixtures.

[0012] The properties of the mineral admixture produced in the above manner are as follows:

[0013] It can be seen from the table that the mineral admixture provided by the present invention has performance that meets the strength requirements of cement, can replace the use of cement in product applications, and has been promoted and applied, thereby improving the green recycling of steel enterprises.

[0014] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A method for producing a mineral admixture from converter slag, characterized in that: The converter slag raw materials and their percentages of the mineral admixture include: SiO2: 10-13%, CaO: 35-45%, Al2O3: 1-3%, Fe2O3: 5-8%, MgO: 8-12%, and the converter slag is finely ground and mixed with slag, desulfurized gypsum, water, and waste sand in a ratio of 1:4:1:

10. Its performance requirements are as follows: 5.0% ≤ sulfur trioxide < 12.0%, chloride ion content ≤ 0.06%, density ≥ 2.8g / m 3 , fineness, i.e. 45μm square hole sieve residue ≤10.0%, initial setting time ≥60min, final setting time ≤600min.

2. The method for producing mineral admixture from converter slag according to claim 1, characterized in that: The performance requirements of the mineral admixture include: sulfur trioxide: 5.0-11.99%, chloride ion content ≤ 0.06%, density ≥ 2.8 g / m 3 ; Fineness, i.e., the residue on 45μm square hole sieve is ≤10.0%, initial setting time is ≥60min, and final setting time is ≤600min.

3. The method for producing mineral admixture from converter slag according to claim 1, characterized in that: The performance requirements of the mineral admixture include: sulfur trioxide: 6.0-11.0%, chloride ion content ≤ 0.05%, density ≥ 2.9 g / m 3 ; Fineness, i.e., the residue on 45μm square hole sieve is ≤9.0%, initial setting time is ≥70min, and final setting time is ≤500min.

4. A method for producing mineral admixtures from converter slag as claimed in claim 1, characterized in that: (1) Lime is used to desulfurize the molten iron before it enters the furnace, and then the slag is removed after desulfurization. The slag is then recovered; (2) After the converter is finished tapping, slag splashing and furnace protection operation is carried out. After slag splashing, the slag is introduced into the slag spray for recovery; (3) The recovered desulfurization slag and converter slag are transported to the slag treatment workshop for slag stewing operation, and the stewing time is 3 to 5 days; (4) The slag after slagging is pulverized and mixed with slag, desulfurized gypsum, water, and waste sand in a ratio of 1:4:1:10; (5) The stirring temperature is 0-50°C, and cementitious materials are added to prepare mineral admixtures.

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