Method for improving pelletizing performance of vanadium-titanium pellets in laboratory

Abstract

The invention discloses a method for improving the pelletizing performance of vanadium-titanium pellets in a laboratory, which comprises the following steps: pelletizing by using a pelletizing disc and a sieve commonly used in the laboratory, and screening out mother pellets with the particle size of 10-12.5 mm as qualified vanadium-titanium pellets; the pellets obtained by the method are uniform in size, and the raw compressive strength, the cooked compressive strength, the drop strength performance and the yield are superior to those of a conventional pelletizing method; the pellet performance can completely meet the experiment research requirement, the experiment requirement target can be accurately controlled, iron and steel enterprises or research units can be helped to better complete various pellet pelletizing experiments, the adjustment basis of operation parameters can be provided for pellet production factories, the green pellet quality and the finished product yield of schreyerite pellets can be improved, and the production cost can be reduced. Certain popularization and application values are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of iron and steel metallurgy, and in particular relates to a method for improving the balling performance of laboratory vanadium-titanium pellets. Background Art

[0002] Blast furnace is the core equipment of the steel industry, responsible for converting iron ore into molten iron. In recent years, with the rapid development of my country's steel industry, higher requirements have been put forward for the improvement of blast furnace production efficiency and resource utilization. As a kind of blast furnace raw material, the role and status of pellets in blast furnace production are becoming increasingly prominent. Increasing the proportion of pellets is conducive to optimizing the blast furnace charge structure, improving resource utilization, and reducing production costs. It is of great significance. Pellets are a high-grade and high-utilization blast furnace raw material made by fine grinding, mixing, balling, drying and roasting of iron ore. Pellets have the characteristics of high grade, low water content, high strength, uniform particle size, etc., which can improve the air permeability and liquid permeability of the blast furnace, reduce the resistance in the furnace, reduce fuel consumption, and improve production efficiency.

[0003] In the blast furnace production process, pellets are mainly used to provide iron ore resources, and their proportion in the blast furnace charge directly affects the production performance of the blast furnace. Increasing the proportion of pellets can effectively improve the grade of the blast furnace, reduce production costs, and improve resource utilization. In addition, pellets also have good environmental performance and can reduce the emission of pollutants such as dust and SO2 during the blast furnace production process.

[0004] The vanadium-titanium magnetite concentrate has high TiO2 content, coarse particle size, small specific surface area, poor balling performance, poor high-temperature consolidation, and low compressive strength of finished pellets. Common vanadium-titanium ore pellets are made by disc pelletizing machines. The whole process from the nucleation of the concentrate to the formation of mother balls to the finished green balls is continuous, but due to uneven water distribution and material adhesion, irregular mother balls are prone to appear, resulting in poor sphericity of the finished balls, large differences in particle size, low yield rate and many other problems. Summary of the invention

[0005] In order to overcome the defects of the above-mentioned prior art, the present invention uses the pelletizing disk and sieve commonly used in the laboratory to make pellets, so that the pellet performance meets the requirements of experimental research, and can accurately control the experimental conditions, helping steel companies or research institutions to better complete various pelletizing experiments, and providing a basis for adjusting operating parameters for pelletizing production plants.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides a method for improving the balling performance of laboratory vanadium-titanium pellets, the method comprising the following steps:

[0007] ① Make mother balls by placing the materials on a ball-making plate with a diameter of 1m according to the proportion;

[0008] ② The obtained mother balls are screened for the first time with a 3mm mesh sieve, the balls on the sieve are eliminated, and the mother balls below the sieve are retained to continue ball making;

[0009] ③ Add materials to the undersize mother balls obtained in step ② to form balls. When the particle size of the mother balls is greater than 3 mm, use sieves with a mesh size of 3 mm and a mesh size of 6 mm to screen them. Keep the mother balls with a particle size of 3 to 6 mm and eliminate the rest of the mother balls.

[0010] ④ Add materials to the cue balls between 3 and 6 mm obtained in step ③ to form balls. When the particle size of the cue balls is greater than 6 mm, sieve them with sieves with mesh size of 6 mm and 8 mm, and keep the cue balls between 6 and 8 mm, and eliminate the rest;

[0011] ⑤ Continue to add materials to the mother balls with a particle size of 6 to 8 mm obtained in step ④ to make balls. When the particle size of the mother balls is greater than 10 mm, screen out the mother balls with a particle size of 10 to 12.5 mm as qualified vanadium-titanium pellets, and return the mother balls with a particle size greater than 12.5 mm to the raw materials. The ball making is completed and vanadium-titanium pellets are obtained.

[0012] In the above technical solution, further, the material is vanadium-titanium magnetite concentrate, and bentonite is used as a binder; the added amount of the binder is 1-3% of the mass of the vanadium-titanium magnetite concentrate.

[0013] Furthermore, in the above steps, the moisture content of the mother ball is controlled to be 7.8% to 8.2%.

[0014] Furthermore, the mother balls eliminated in the ball making process in the above steps are crushed and returned to the ball making process as raw materials to ensure that no raw materials are wasted.

[0015] The vanadium-titanium pellets produced by this method are uniform in size, and their raw and cooked compressive strength, drop strength performance, and yield rate are superior to those of conventional pelletizing methods.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention uses the pelletizing disk and sieve commonly used in the laboratory to make pellets, so that the performance of the pellets meets the requirements of experimental research and can accurately achieve the experimental goals, help steel companies or research institutions to better complete various pelletizing experiments, and provide a basis for adjusting operating parameters for pelletizing plants, which is beneficial to improving the quality of raw vanadium-titanium ore pellets and the output of finished products, and has certain innovation and value for promotion and application. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with specific examples, but the present invention is not limited in any way. To avoid redundant description, the raw materials in the following examples are all commercially available products unless otherwise specified, and the methods used are all conventional methods unless otherwise specified.

[0019] A method for improving the balling performance of laboratory vanadium-titanium pellets, the method comprising the following steps:

[0020] ① Make mother balls by placing the materials on a ball-making plate with a diameter of 1m according to the proportion;

[0021] ② The obtained mother balls are screened for the first time with a 3mm mesh sieve, the balls on the sieve are eliminated, and the mother balls below the sieve are retained to continue ball making;

[0022] ③ Add materials to the undersize mother balls obtained in step ② to form balls. When the particle size of the mother balls is greater than 3 mm, use sieves with a mesh size of 3 mm and a mesh size of 6 mm to screen them. Keep the mother balls with a particle size of 3 to 6 mm and eliminate the rest of the mother balls.

[0023] ④ Add materials to the cue balls between 3 and 6 mm obtained in step ③ to form balls. When the particle size of the cue balls is greater than 6 mm, sieve them with sieves with mesh size of 6 mm and 8 mm, and keep the cue balls between 6 and 8 mm, and eliminate the rest;

[0024] ⑤ Continue to add materials to the mother balls with a particle size of 6 to 8 mm obtained in step ④ to make balls until the particle size of the mother balls is greater than 10 mm, and select mother balls with a particle size of 10 to 12.5 mm as qualified vanadium-titanium pellets.

[0025] The matters not described in the following embodiments are the same as the description of the above specific implementation methods.

[0026] Example 1

[0027] A method for improving the balling performance of laboratory vanadium-titanium pellets, using vanadium-titanium magnetite concentrate as raw material and bentonite as binder; the amount of the binder added is 2% of the mass of the vanadium-titanium magnetite concentrate; the moisture content of the mother ball is controlled to be 8.0% during the preparation process; the specific process flow is:

[0028] ① Make mother balls by placing the materials on a ball-making plate with a diameter of 1m according to the proportion;

[0029] ② The obtained mother balls are screened for the first time with a 3mm mesh sieve, the balls on the sieve are eliminated, and the mother balls below the sieve are retained to continue ball making;

[0030] ③ Add materials to the undersize mother balls obtained in step ② to form balls. When the particle size of the mother balls is greater than 3 mm, use sieves with a mesh size of 3 mm and a mesh size of 6 mm to screen them. Keep the mother balls with a particle size of 3 to 6 mm and eliminate the rest of the mother balls.

[0031] ④ Add materials to the cue balls between 3 and 6 mm obtained in step ③ to form balls. When the particle size of the cue balls is greater than 6 mm, sieve them with sieves with mesh size of 6 mm and 8 mm, and keep the cue balls between 6 and 8 mm, and eliminate the rest;

[0032] ⑤ Continue to add materials to the mother balls with a particle size of 6 to 8 mm obtained in step ④ to make balls until the particle size of the mother balls is greater than 10 mm, and select mother balls with a particle size of 10 to 12.5 mm as qualified vanadium-titanium pellets.

[0033] The vanadium-titanium pellets prepared in Example 1 were tested for performance, and the drop strength was 9 times, the compressive strength of the green pellets was 12.3N, the compressive strength of the cooked pellets was 2861N, and the yield was 90%.

[0034] Example 2

[0035] A method for improving the balling performance of laboratory vanadium-titanium pellets, using vanadium-titanium magnetite concentrate as raw material and bentonite as binder; the amount of the binder added is 2% of the mass of the vanadium-titanium magnetite concentrate; the moisture content of the mother ball is controlled to be 8.0% during the preparation process; the specific process flow is:

[0036] ① Make mother balls by placing the materials on a ball-making plate with a diameter of 1m according to the proportion;

[0037] ② The obtained mother balls are screened for the first time with a 3mm mesh sieve, the balls on the sieve are eliminated, and the mother balls below the sieve are retained to continue ball making;

[0038] ③ Continue to pelletize the mother balls obtained in step ②. When the particle size of the mother balls is greater than 3 mm, use sieves with a mesh size of 3 mm and a mesh size of 6 mm to screen them. Keep the mother balls with a particle size of 3 to 6 mm and eliminate the rest of the mother balls.

[0039] ④ Continue to pelletize the cue balls between 3 and 6 mm obtained in step ③. When the particle size of the cue balls is greater than 6 mm, screen them with sieves with mesh size of 6 mm and 8 mm, and keep the cue balls between 6 and 8 mm, and eliminate the rest of the cue balls;

[0040] ⑤ Continue to pelletize the mother balls with a particle size of 6 to 8 mm obtained in step ④ until the particle size of the mother balls is greater than 10 mm, and select the mother balls with a particle size of 10 to 12.5 mm as qualified vanadium-titanium pellets.

[0041] The vanadium-titanium pellets prepared in Example 2 were tested for performance, and the drop strength was 8 times, the compressive strength of the green pellets was 13.1N, the compressive strength of the cooked pellets was 2653N, and the yield was 83%.

[0042] Comparative Example 1

[0043] A method for improving the balling performance of laboratory vanadium-titanium pellets, using vanadium-titanium magnetite concentrate as raw material and bentonite as binder; the amount of the binder added is 2% of the mass of the vanadium-titanium magnetite concentrate; the moisture content of the mother ball is controlled to be 8.0% during the preparation process; the specific process flow is:

[0044] ① Make mother balls by placing the materials on a ball-making plate with a diameter of 1m according to the proportion;

[0045] ② When the particle size of the mother balls is greater than 10mm, stop making balls;

[0046] ③ The mother balls obtained in step ② are screened to select mother balls with a particle size of 10 to 12.5 mm as qualified vanadium-titanium pellets, and the remaining mother balls are eliminated; and vanadium-titanium pellets are obtained.

[0047] The vanadium-titanium pellets prepared in Comparative Example 1 were tested for performance, and the drop strength was 2.5 times, the compressive strength of the green ball was 9.4N, the compressive strength of the cooked ball was 2249N, and the yield rate was 65%. In the conventional pelletizing process of Comparative Example 1, there was no screening process for the mother ball in the middle, and there was no multiple particle size classification, so that the yield rate of the mother ball was not high and the performance of the pellets was also poor.

[0048] It can be seen from the experimental data of the above embodiments and comparative examples that the vanadium-titanium pellets prepared by the present technical solution are uniform in size, and the raw and cooked compressive strength, drop strength performance and yield rate are better than those of the conventional pelletizing method.

[0049] For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention should still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for improving the balling performance of laboratory vanadium-titanium pellets, characterized in that: The method comprises the following steps: ①Prepare the materials on a 1m diameter ball-making plate according to the proportion to prepare the mother ball; ② The obtained mother balls are screened for the first time with a 3mm mesh sieve, the balls on the sieve are eliminated, and the mother balls below the sieve are retained to continue ball making; ③ Continue to pelletize the mother balls obtained in step ②. When the particle size of the mother balls is greater than 3 mm, use sieves with a mesh size of 3 mm and a mesh size of 6 mm to screen them. Keep the mother balls with a particle size of 3 to 6 mm and eliminate the rest of the mother balls. ④ Continue to pelletize the cue balls between 3 and 6 mm obtained in step ③. When the particle size of the cue balls is greater than 6 mm, screen them with sieves with mesh size of 6 mm and 8 mm, and keep the cue balls between 6 and 8 mm, and eliminate the rest of the cue balls; ⑤ Continue to pelletize the mother balls with a particle size of 6 to 8 mm obtained in step ④ until the particle size of the mother balls is greater than 10 mm, and select the mother balls with a particle size of 10 to 12.5 mm as qualified vanadium-titanium pellets.

2. The method according to claim 1, characterized in that Step ① The material is vanadium-titanium magnetite concentrate, and bentonite is used as a binder; the amount of the binder added is 1% to 3% of the mass of the vanadium-titanium magnetite concentrate.

3. The method according to claim 1, characterized in that The moisture content of the mother ball is controlled to be 7.8% to 8.2%.

4. The method according to claim 1, characterized in that: The mother balls eliminated in the ball making process are crushed and returned to the ball making process as raw materials.