Mineral admixture prepared based on blast furnace slag and production method thereof

Abstract

The invention discloses a mineral admixture prepared based on blast furnace slag. The mineral admixture comprises the following chemical components in percentage by weight: 58-63% of CaO, 18-26% of SiO2, 3-9% of Al2O3, 5-8% of Fe2O3, 1-3% of MgO, 1-3% of Na2O and the balance of impurities. The recycled blast furnace slag, the slag, the desulfurized gypsum, the water and the waste rock sand are reasonably proportioned, mixed and stirred to prepare the mineral admixture meeting the requirements for compressive strength and breaking strength, batch supply of products is achieved, and the mineral admixture has the advantages that the production process is improved, the utilization rate of the blast furnace slag is increased, the use performance of the admixture is improved, and the universality of the admixture is expanded.

Description

Technical Field

[0001] The invention belongs to the technical field of iron and steel metallurgy, and in particular relates to a mineral admixture manufactured based on blast furnace slag and a production method thereof. Background Art

[0002] Blast furnace slag is a by-product of iron smelting, accounting for about 20% to 30% of steel production. In recent years, with the rapid development of my country's steel industry, the amount of iron slag produced has also increased year by year. After water quenching, the main mineral composition of iron slag is silicon-alumina glass, which has good potential hydraulic hardness and can be ground into concrete admixtures. The comprehensive utilization rate of iron 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 iron slag powder can also help steel plants solve the environmental pressure of "zero emission" of iron slag. At present, blast furnace slag cannot be effectively utilized. Even if part of it can be converted into admixtures for use in actual production, the compressive strength and flexural strength of the admixtures are relatively weak, and the poor performance has greatly limited its use effect. Summary of the invention

[0003] The purpose of the present invention is to solve the problems of low utilization rate of existing blast furnace slag, poor performance of admixtures and limited effects, and to provide a method for manufacturing mineral admixtures based on blast furnace slag, improve the production process, increase the utilization rate of blast furnace slag, enhance the performance of admixtures and expand their versatility.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A mineral admixture made from blast furnace slag, the chemical composition and percentage thereof include: CaO: 58-63%, SiO2: 18-26%, Al2O3: 3-9%, Fe2O3: 5-8%, MgO: 1-3%, Na2O: 1-3%, and the rest are impurities. The invention adopts recycled blast furnace slag and slag, desulfurized gypsum, water, and waste sand to mix and stir in a reasonable ratio to make a mineral admixture that meets the requirements of compressive strength and flexural strength, so as to realize batch supply of the product.

[0005] Furthermore, the chemical composition and percentage of the mineral admixture include: CaO: 60-63%, SiO2: 20-26%, Al2O3: 5-9%, Fe2O3: 6-8%, MgO: 2-3%, Na2O: 2-3%, and the rest are impurities.

[0006] Furthermore, the chemical composition and percentage of the mineral admixture include: CaO: 58-60%, SiO2: 18-23%, Al2O3: 3-6%, Fe2O3: 5-7%, MgO: 1-2%, Na2O: 1-2%, and the rest are impurities.

[0007] In order to further achieve the purpose of the present invention, a production method for producing a mineral admixture based on blast furnace slag and a production method thereof is also provided, and the specific steps are as follows: (1) 70-75% of sintered ore, 10-15% of pelletized ore, 10-15% of raw ore, and 5-10% of coke are transported to the top of the blast furnace by belt conveyor, and then molten iron is smelted in the blast furnace; (2) When the temperature of the molten iron reaches 1400-1500°C, the iron is tapped and the molten iron passes through a slag skimmer to separate the slag from the iron. (3) The separated iron slag is transported to the slag treatment workshop for slag stewing operation. The stewing time is 4 to 8 hours and the stewing temperature is 800 to 1200°C; (4) The blast furnace slag after slagging is ground and powdered, and mixed with gypsum, water, and waste sand in a ratio of 3:4:1:7; (5) The stirring temperature is 0-50°C, and cementitious materials are added to prepare mineral admixtures.

[0008] Furthermore, in step (1), the proportions of the components are 73% sintered ore, 12% pelletized ore, 12% raw ore, and 6% coke.

[0009] Furthermore, in step (1), the proportions of the components are 71% sintered ore, 13% pelletized ore, 14% raw ore, and 9% coke.

[0010] Furthermore, in the step (2), the tapping operation is performed when the molten iron temperature reaches 1456°C or 1485°C.

[0011] Furthermore, in the step (3), the slag stewing time is 5 h or 6 h, and the corresponding slag stewing temperature is 916° C. or 1106° C.

[0012] Furthermore, in the step (5), the stirring temperature is 30°C or 33°C.

[0013] Compared with the prior art, the advantages of the technical solution of the present invention are: (1) The present invention rationally utilizes blast furnace slag to produce mineral admixture raw materials through a process, effectively reducing the pollution of blast furnace slag to the ground and water quality in the factory area, realizing green and clean production in the steel industry and improving the image of the enterprise; (2) After physical and chemical property testing, 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 pulverization of slag and mixing with gypsum, water and waste sand in a ratio of 3:4:1:7 is obtained through continuous practice verification. It has a unique formula use right and can be used by other enterprises, which has product versatility. DETAILED DESCRIPTION Example 1

[0014] In order to make the present invention more clear, the following further describes a method for producing a mineral admixture based on blast furnace slag and a production method thereof. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0015] The mineral admixtures for manufacturing a blast furnace slag in this embodiment are: CaO: 61%, SiO2: 23%, Al2O3: 7%, Fe2O3: 7%, MgO: 2.3%, Na2O: 2.7%, and the rest are impurities.

[0016] Among them, a production method for producing mineral admixtures from blast furnace slag is characterized by: S1, 73% sintered ore, 12% pelletized ore, 12% raw ore, and 6% coke are transported to the top of the blast furnace by belts, and then molten iron is smelted in the blast furnace; S2, the molten iron temperature reaches 1456℃ and the tapping operation is carried out. The molten iron passes through the slag skimmer to separate the slag and iron; S3, the separated iron slag is transported to the slag treatment workshop for slag stewing operation, the slag stewing time is 5h, and the slag stewing temperature is 916℃; S4, grinding and powdering the blast furnace slag after slagging, and mixing with gypsum, water, and waste sand in a ratio of 3:4:1:7; S5, stirring at 30°C, adding cementitious materials to prepare mineral admixtures; Example 2

[0017] The mineral admixtures for manufacturing a blast furnace slag in this embodiment are: CaO: 59%, SiO2: 22%, Al2O3: 5%, Fe2O3: 5%, MgO: 2%, Na2O: 1.7%, and the rest are impurities.

[0018] Among them, a production method for manufacturing mineral admixtures from converter slag specifically includes: S1, 71% of sintered ore, 13% of pelletized ore, 14% of raw ore and 9% of coke are transported to the top of the blast furnace by belts, and then molten iron is smelted in the blast furnace; S2, the molten iron temperature reaches 1485℃ and the tapping operation is carried out. The molten iron passes through the slag skimmer to separate the slag and iron; S3, the separated iron slag is transported to the slag treatment workshop for slag stewing operation, the slag stewing time is 6h, and the slag stewing temperature is 1106℃; S4, grinding and powdering the blast furnace slag after slagging, and mixing with gypsum, water, and waste sand in a ratio of 3:4:1:7; S5, stirring temperature 33 ℃, adding cementitious materials to prepare mineral admixture The properties of the mineral admixture produced according to the above embodiment are as follows:

[0019] 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.

[0020] 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 based on blast furnace slag, characterized in that: The chemical composition and percentage of the mineral admixture include: CaO: 58-63%, SiO2: 18-26%, Al2O3: 3-9%, Fe2O3: 5-8%, MgO: 1-3%, Na2O: 1-3%, and the rest are impurities.

2. The method for producing mineral admixtures based on blast furnace slag according to claim 1, characterized in that: The chemical composition and percentage of the mineral admixture include: CaO: 60-63%, SiO2: 20-26%, Al2O3: 5-9%, Fe2O3: 6-8%, MgO: 2-3%, Na2O: 2-3%, and the rest are impurities.

3. The method for producing mineral admixtures based on blast furnace slag according to claim 1, characterized in that: The chemical composition and percentage of the mineral admixture include: CaO: 58-60%, SiO2: 18-23%, Al2O3: 3-6%, Fe2O3: 5-7%, MgO: 1-2%, Na2O: 1-2%, and the rest are impurities.

4. A method for producing a mineral admixture based on blast furnace slag and a production method thereof as claimed in claim 1, characterized in that: (1) 70-75% of sintered ore, 10-15% of pelletized ore, 10-15% of raw ore, and 5-10% of coke are transported to the top of the blast furnace by belt conveyor, and then molten iron is smelted in the blast furnace; (2) When the temperature of the molten iron reaches 1400-1500°C, the iron is tapped and the molten iron passes through a slag skimmer to separate the slag from the iron. (3) The separated iron slag is transported to the slag treatment workshop for slag stewing operation. The stewing time is 4 to 8 hours and the stewing temperature is 800 to 1200°C; (4) The blast furnace slag after slagging is ground and powdered, and mixed with gypsum, water, and waste sand in a ratio of 3:4:1:7; (5) The stirring temperature is 0-50°C, and cementitious materials are added to prepare mineral admixtures.

5. The method for producing mineral admixtures based on blast furnace slag and the production method thereof according to claim 4, characterized in that: In the step (1), the proportions of the components are 73% sintered ore, 12% pelletized ore, 12% raw ore, and 6% coke.

6. The method for producing mineral admixtures based on blast furnace slag and its production method according to claim 4, characterized in that: In the step (1), the proportions of the components are 71% sintered ore, 13% pelletized ore, 14% raw ore, and 9% coke.

7. The method for producing mineral admixtures based on blast furnace slag and its production method according to claim 4, characterized in that: In the step (2), the tapping operation is performed when the molten iron temperature reaches 1456°C or 1485°C.

8. The method for producing mineral admixtures based on blast furnace slag and its production method according to claim 4, characterized in that: In the step (3), the slag stewing time is 5 hours or 6 hours, and the corresponding slag stewing temperature is 916°C or 1106°C.

9. The method for producing mineral admixtures based on blast furnace slag and the production method thereof according to claim 4, characterized in that: In the step (5), the stirring temperature is 30°C or 33°C.

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