A method for detecting the hot performance of tuyere
By obtaining tuyeres coke during blast furnace shutdown and grinding it into ellipsoids for thermal performance testing, the problems of difficulty in obtaining tuyeres coke samples and equipment damage were solved, and high-precision tuyeres coke thermal performance testing was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INNER MONGOLIA BAOTOU STEEL UNION
- Filing Date
- 2026-04-15
- Publication Date
- 2026-07-17
AI Technical Summary
It is difficult to obtain samples of blast furnace coke, and the quantity is small and the coke is severely degraded, which makes it difficult to test its thermal properties. Furthermore, existing methods are prone to damaging equipment.
During blast furnace shutdown, tuyeres coke is collected, manually selected, and ground into ellipsoids for thermal performance testing, including reaction with CO2 gas and strength testing.
This improved the accuracy and repeatability of vent scorch performance testing and reduced the risk of sample damage.
Abstract
Description
Technical Field
[0001] This invention belongs to the field of blast furnace ironmaking technology, and particularly relates to a method for detecting the coke heat performance of tuyeres. Background Technology
[0002] Blast furnace tuyere coke is the residue after undergoing high temperature and complex physicochemical reactions in the blast furnace. Its thermal properties (reactivity CRI and post-reaction strength CSR) are key indicators for evaluating the degree of coke deterioration in the furnace and reflecting the operating status of the blast furnace. However, there has always been a huge challenge in standardizing the thermal performance testing of tuyere coke. The main problems are: (1) it is difficult to obtain samples. The amount of tuyere coke samples is small, and the samples that can be used for testing are extremely limited due to the difficulty in taking them out from the central area of the blast furnace; (2) tuyere coke has undergone severe corrosion, and the particle size is generally small, the shape is extremely irregular, the surface is covered with slag, the internal cracks are low, and the strength is low; (3) the surface or middle of the tuyere coke has high iron content and the equipment is easily damaged during the sample preparation process.
[0003] Therefore, there is an urgent need for a method that can effectively handle special, degraded, and small-particle samples such as fumed coke, and enable standardized and highly repeatable thermal performance testing. Summary of the Invention
[0004] To address the aforementioned technical challenges, the present invention aims to provide a feasible and reliable method for detecting the scorching performance of air vents.
[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0006] This invention discloses a method for detecting the scorching performance of an air vent, which specifically includes the following steps:
[0007] (1) During the blast furnace shutdown period, tuyere coke with a mass >20kg is obtained by scraping the tuyere;
[0008] (2) After removing obvious slag and iron from the surface of the coke sample obtained in step (1), manually select coke blocks with relatively high mechanical strength, capable of withstanding subsequent grinding and with a size of more than 30mm.
[0009] (3) The coke screened in step (2) is processed into an ellipsoid by manual or auxiliary mechanical grinding.
[0010] (4) Weigh a certain mass of the ellipsoidal duct coke that was polished in step (3) and put it into the reactor. React it with pure CO2 gas at a constant temperature of 1100±5℃. After the reaction is completed, cool it to room temperature under N2 protection.
[0011] (5) Take out the sample after the reaction in (4) and test its strength using a test drum device; after the test, sieve it with a 10mm sieve and measure the mass of the dried material.
[0012] (6) Calculate the CRI and CSR of coke respectively to obtain the test results.
[0013] Furthermore, the major axis of the ellipsoid is controlled to be below 25mm, and the minor axis is not less than 23mm.
[0014] Furthermore, the ellipsoid has a smooth surface without obvious edges or sharp points.
[0015] Furthermore, 200g of the ellipsoidal tuyeres coke polished in step (3) is weighed and placed into the reactor.
[0016] Furthermore, in step (4), the mixture is reacted with pure CO2 gas for 2 hours.
[0017] Furthermore, in step (2), 20-30 pieces of coke with a particle size >30mm are selected, and the structure is relatively dense with no obvious through cracks on the surface.
[0018] Furthermore, digital calipers are used for measurement and monitoring to ensure that the major axis of the processed sample is 25±0.2mm, while ensuring that the ellipsoid shape is uniform and the surface is smooth.
[0019] Compared with the prior art, the beneficial technical effects of the present invention are as follows:
[0020] The blast furnace coke samples prepared by this invention show significantly higher accuracy in thermal performance testing compared to irregular blast furnace coke samples, and the repeatability and reliability of the data are greatly improved. Detailed Implementation
[0021] A feasible and reliable method for testing the scorch performance of vents includes the following steps:
[0022] (1) During the blast furnace shutdown period, tuyere coke with a mass >20kg is obtained by scraping the tuyere;
[0023] (2) After removing obvious slag and iron from the surface of the coke sample obtained in step (1), manually select coke blocks with relatively high mechanical strength, capable of withstanding subsequent grinding and with a size of more than 30mm.
[0024] (3) The coke screened in step (2) is processed into an ellipsoid by manual or auxiliary mechanical grinding. The major axis dimension of the ellipsoid is controlled to be below 25 mm, the minor axis dimension is not less than 23 mm, and the sample surface is ensured to be smooth and without obvious edges and sharp points;
[0025] (4) Weigh 200g of the ellipsoidal tuyeres coke prepared in step (3) and place it in the reactor. React it with pure CO2 gas at a constant temperature of 1100±5℃ for 2 hours. After the reaction is complete, cool it to room temperature under N2 protection.
[0026] (5) Take out the sample after the reaction in step (4) and test its strength using a test drum device. After the test, sieve it with a 10mm sieve and measure the mass of the dried material;
[0027] (6) Calculate the CRI and CSR of coke respectively to obtain the test results.
[0028] The technical solution of the present invention will be described in detail below with reference to the embodiments.
[0029] In this embodiment of the invention, Baotou Steel tuyere coke was selected as the test coke. In the laboratory, completely pulverized and surface slag and iron were manually removed. Then, 20-30 pieces of coke with a particle size >30mm were selected, exhibiting a relatively dense structure and no obvious through-cracks on the surface. Each piece of coke was then polished with fine sandpaper into an ellipsoid. A digital caliper was used for measurement and monitoring to ensure that the major axis of the processed sample was 25±0.2mm, while maintaining a uniform ellipsoidal shape and a smooth surface. The successfully prepared qualified ellipsoidal samples were randomly divided into 3 groups (numbered 1#-3#), 200g per group. Thermal reaction and strength tests were conducted according to the aforementioned steps. For comparison, 3 groups of large coke pieces (23-25mm) of similar size but irregular shape were directly selected from the same batch of tuyere coke and subjected to the same tests without polishing.
[0030] The test results are shown in Table 1. It can be seen that the sample groups prepared using this method all exhibited small deviations, and the three groups showed good consistency. In contrast, the control sample group, due to its irregular shape, broke violently in the drum, resulting in larger deviations and indicating greater random error. Therefore, the method of this invention has a significant effect on improving detection accuracy and reliability.
[0031] Table 1. Comparison of thermal properties of coke, %
[0032] CRI CSR Fengkou Jiao 1# 48.2 40.6 Fengkou Jiao 2# 47.3 40.7 Fengkou Jiao 3# 48.7 41.2 Air vent 4# 57.3 40.9 Air vent slag #5 46.8 39.2 Wind-blown coke #6 45.8 43.6
[0033] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. A method for detecting the scorching performance of an air vent, characterized in that, Specifically, the steps include the following: (1) During the blast furnace shutdown period, tuyere coke with a mass >20kg is obtained by scraping the tuyere; (2) After removing obvious slag and iron from the surface of the coke sample obtained in step (1), manually select coke blocks with relatively high mechanical strength, capable of withstanding subsequent grinding, and with a size of more than 30mm. (3) The coke screened in step (2) is processed into an ellipsoid by manual or auxiliary mechanical grinding. (4) Weigh a certain mass of the ellipsoidal duct coke that was polished in step (3) and put it into the reactor. React it with pure CO2 gas at a constant temperature of 1100±5℃. After the reaction is completed, cool it to room temperature under N2 protection. (5) Take out the sample after the reaction in (4) and test its strength using a test drum device; after the test, sieve it with a 10mm sieve and measure the mass of the dried material. (6) Calculate the CRI and CSR of coke respectively to obtain the test results.
2. The method for detecting the scorching performance of an air vent according to claim 1, characterized in that, The major axis of the ellipsoid is controlled to be below 25mm, and the minor axis is not less than 23mm.
3. The method for detecting the scorching performance of an air vent according to claim 2, characterized in that, The ellipsoid has a smooth surface with no obvious edges or sharp points.
4. The method for detecting the scorching performance of an air vent according to claim 1, characterized in that, Weigh 200g of the ellipsoidal tuyeres coke that was polished in step (3) and put it into the reactor.
5. The method for detecting the scorching performance of an air vent according to claim 1, characterized in that, In step (4), the mixture reacts with pure CO2 gas for 2 hours.
6. The method for detecting the scorching performance of an air vent according to claim 1, characterized in that, In step (2), 20-30 pieces of coke with a particle size >30mm are selected, and the structure is relatively dense with no obvious through cracks on the surface.
7. The method for detecting the scorching performance of an air vent according to claim 2, characterized in that, Digital calipers were used for measurement and monitoring to ensure that the major axis of the processed sample was 25±0.2mm, while also ensuring that the ellipsoid shape was uniform and the surface was smooth.