An evaluation device and method for simulating coke quality in a blast furnace environment

Abstract

This invention relates to an evaluation device and method for simulating coke quality under blast furnace conditions. The device includes a reactor body, a reaction tube, a vessel disc, a lifting platform, and a pressurizing device. The reaction tube is disposed within the reactor body, and its upper and lower ends are sealed by flanges. The lifting platform is located at the lower part of the reaction tube and can drive the vessel disc to move up and down within the reaction tube. The pressurizing device is located at the upper part of the reaction tube and can apply pressure to the material in the vessel disc. The reaction tube also has an inlet and an outlet, and a perforated sieve plate is fixed in the middle of the reaction tube. This invention can simulate the real environment of coke in a blast furnace. The coke is subjected not only to the static pressure of the material above but also to the atmospheric conditions such as carbon dioxide and alkali metal atmospheres within the blast furnace, enabling a more realistic and effective evaluation of coke quality and providing reasonable guidance for the correct application of coke.

Description

Technical Field

[0001] This invention relates to the fields of blast furnace ironmaking and coking technology, and specifically to an evaluation device and method for simulating coke quality under blast furnace conditions. Background Technology

[0002] Reducing coke consumption is one of the key methods to reduce greenhouse gas emissions and energy consumption in the current blast furnace ironmaking process. Due to the shortage of high-quality coking coal resources and the continuous improvement of blast furnace technology and operation, the consumption of blast furnace fuel and coke is constantly decreasing. As a result, the skeletal role of coke in the high-temperature zone of the blast furnace is becoming more and more prominent.

[0003] Currently, the evaluation of the hot properties of coke in China is mainly based on GB / T4000-2008 Test Method for Coke Reactivity and Post-Reaction Strength. This method stipulates that coke is reacted with 100% carbon dioxide at 1100℃±5℃ for 2 hours. The coke reactivity (CRI) is expressed as the percentage of coke mass loss. After the coke is subjected to a Type I drum test, the post-reaction strength (CSR) is expressed as the mass fraction of coke particles larger than 10mm in the post-reaction coke.

[0004] The deterioration of coke in a blast furnace is influenced by many factors, such as mechanical damage from the extrusion and wear of the furnace body materials, thermal stress damage caused by high-temperature gas heating, the dissolution reaction of CO2 in the coke, and the erosion of the coke by the liquid slag and iron below the melting zone. Both mechanical damage and chemical erosion can impair the strength and dimensions of the coke, further affecting the gas and liquid permeability in the blast furnace.

[0005] Existing research both domestically and internationally has shown that the catalytic effect of iron on the reactivity of coke is well-known. With the deepening of research on blast furnace anatomy both domestically and internationally, people have gained a better understanding of the distribution of reactions inside the blast furnace and have confirmed that the high-temperature zone (above 1000℃) inside the blast furnace contains a large amount of alkali.

[0006] In recent years, with in-depth research on the melting reaction of coke in blast furnaces, numerous studies have shown that the most severe structural damage to coke during its downward movement from the blast furnace to the tuyeres occurs during the softening zone, due to the carbon dissolution reaction of CO2. The degree of coke damage after passing through this zone determines the smooth operation of the entire blast furnace. However, with the analysis of blast furnace dissections both domestically and internationally, a better understanding of the distribution of alkali metals in blast furnaces has been gained, confirming that high-temperature zones (above 1000℃) contain high levels of alkali metals. The presence of alkali metals in the blast furnace is one of the main reasons for the exacerbated carbon melting reaction of coke. While considerable research has been conducted on coke quality evaluation both domestically and internationally, current laboratory setups cannot accurately simulate the environment inside a blast furnace. Some cokes may not have high initial reactivity, but due to their strong resistance to alkali metal vapors, their performance in the high-temperature zones of the blast furnace may be quite significant.

[0007] The patent application with application number CN202010472478.X discloses a device for simulating the coke reaction in the high-temperature section of a blast furnace. However, this device only involves the situation where liquid slag and iron drips and washes over the coke in the high-temperature section of the blast furnace. In the blast furnace, the coke is not only subjected to high temperature and washing by liquid slag and iron, but also, through the dissection of the blast furnace, it can be seen that the coke is affected by the alkali metal atmosphere, the influence of gases such as carbon dioxide in the blast furnace, and the pressure of the materials piled above, as well as many other environmental factors.

[0008] The patent application with application number CN111401774A proposes a comprehensive evaluation method for coke quality. This method merely uses existing indicators such as ash content, sulfur content, M40, M10, post-reaction strength (CSR), and reactivity (CRI) to assign a certain weight to each parameter through mathematical relationships. However, this method does not deviate from the scope of traditional coke quality evaluation methods, and the weight selection relies on experience without relevant data support. Furthermore, the relationship cannot satisfy all coke quality evaluations and has certain limitations.

[0009] The coke quality evaluation method disclosed in patent application CN202211038519.X uses reactivity (CRI) and post-reaction strength (CSR) as the primary criteria, and then assesses the coke quality based on the ash catalytic index and the distribution of optical microstructure. However, this method does not deviate from traditional coke evaluation methods and cannot accurately reflect the reaction environment of coke within the blast furnace, thus failing to provide a correct and reasonable evaluation.

[0010] The patent document with application number CN202110613492.1 constructs a raw data matrix (cold strength index and hot strength index) by composing the evaluation indexes of each coke sample within the cycle. The raw data matrix X is standardized and dimensionless. The correlation coefficients of each index are calculated based on the standardization to construct the correlation coefficient matrix R. The expressions of the first 5 comprehensive characteristic indexes are obtained by solving the problem using SPSS software.

[0011] An objective evaluation and analysis of coke quality fluctuations is conducted based on a comprehensive evaluation index expression. This method is also based on conventional cold-state and hot-state strength indices. After data processing, SPSS analysis software is used to solve the relevant expressions, and then the coke quality is evaluated using these expressions. However, this method does not closely approximate the actual behavior of coke in the blast furnace and cannot provide an objective evaluation of coke based on actual conditions.

[0012] Patent application CN202111081664.1 proposes a method for evaluating coke deterioration under simulated dynamic reactions in a blast furnace. This method simulates the reaction of coke in a blast furnace by dynamically controlling temperature and carbon dioxide concentration during the reaction process. However, the actual conditions of coke in different regions of the blast furnace are not simply affected by changes in temperature and carbon dioxide concentration. Therefore, this method cannot accurately simulate the reaction process of coke in a blast furnace and cannot objectively evaluate the quality of the coke.

[0013] In conclusion, the evaluation method based on GB / T4000-2008 is no longer sufficient to objectively and reasonably evaluate the true quality of coke. A deeper understanding of the behavior of coke in the blast furnace is increasingly important for a true, objective, and reasonable evaluation of coke quality. Therefore, a reaction device that can realistically simulate the environment inside the blast furnace is needed to objectively and reasonably evaluate the performance of coke. Summary of the Invention

[0014] The purpose of this invention is to provide an evaluation device and method for simulating the quality of coke in a blast furnace environment. The device can simulate the real environment in which coke is located in a blast furnace. The coke is not only subjected to the static pressure of the upper material, but also to the conditions of the atmosphere such as carbon dioxide and alkali metal atmosphere in the blast furnace. This allows for a more realistic and effective evaluation of the quality of coke and can provide reasonable suggestions for the correct application of coke.

[0015] To achieve the above objectives, the present invention employs the following technical solution:

[0016] An evaluation device simulating coke quality under blast furnace conditions includes a reactor body, a reaction tube, a vessel disc, a lifting device, and a pressurizing device. The reaction tube is installed inside the reactor body, and a perforated sieve plate is fixed in the middle of the reaction tube. The upper and lower ends of the reaction tube are sealed by flanges. The lifting device is installed at the lower part of the reaction tube and can drive the vessel disc to move up and down inside the reaction tube. The pressurizing device is installed at the upper part of the reaction tube and can apply pressure to the material placed on the upper part of the sieve plate. The reaction tube is also provided with an air inlet and an air outlet.

[0017] Within the reactor body, heating elements are arranged in two sections along the longitudinal direction of the reaction tube. The upper heating element heats the material on the sieve plate, while the lower heating element heats the material on the vessel disc. The reactor body has an insulation layer on its outer side and thermocouples are installed inside the furnace wall.

[0018] The heating temperature of the upper heating element is 900℃-1600℃, and the heating temperature of the lower heating element is 700℃-1400℃.

[0019] It also includes thermocouples, which are inserted into the material in the reaction tube from the top end of the reaction tube.

[0020] A method for determining coke quality using an evaluation device simulating a blast furnace environment includes the following steps:

[0021] 1) Crush the coke with a jaw crusher, discard the flaky and strip-shaped coke blocks, and manually grind the remaining coke into granular coke samples with a diameter of 23mm-25mm. Place the prepared granular coke samples into a drying oven, take out the coke, cool it to room temperature, weigh it for later use, and record the mass as m, with the unit being g.

[0022] 2) Open the flange at the bottom of the reaction tube and place the activated carbon powder and sodium carbonate or potassium carbonate on the movable container disc.

[0023] 3) Open the flange at the top of the reaction tube, spread the coke cooled to room temperature on the sieve plate in the middle of the reaction tube, and close the flange at the top.

[0024] 4) Insert the temperature measuring thermocouple through the thermocouple sheath set in the reaction tube into the center of the material layer on the sieve plate;

[0025] 5) Connect the reactor's inlet and outlet pipes to the gas supply and exhaust systems respectively, check the gas path, and ensure it is tight;

[0026] 6) The upper pressurization device applies a pressure of 10±0.1Kpa and heats the upper part of the reaction tube from room temperature to 500℃ at a rate of 5~8℃ / min; when the temperature at the center of the material layer reaches 500±5℃, nitrogen is introduced at a flow rate of 0.8±0.05L / min to protect the coke from burning.

[0027] The heating rate from 500℃ to 900℃ is 3-5℃ / min, and nitrogen gas is continuously passed through at a flow rate of 0.8±0.05L / min.

[0028] The heating rate from 900℃ to 1300℃ is 2-3℃ / min. When the center temperature of the material layer on the sieve plate reaches 1300±5℃, stabilize for 10±0.5min, cut off the nitrogen gas, and switch to carbon dioxide with a flow rate of 5±0.1L / min.

[0029] 7) Continue to heat the upper part of the reaction tube to 1500±10℃ at a rate of 2~3℃ / min; maintain the temperature at 1500±10℃ for 2±0.05h, stop heating, cut off the carbon dioxide gas line, switch to nitrogen gas, and control the flow rate at 2±0.1L / min.

[0030] 8) When the upper part of the reaction tube is heated to 300±10℃, the container disc containing activated carbon powder and sodium carbonate or potassium carbonate sample is raised to 3±0.2cm from the middle sieve plate using the lifting device; the lower part of the reaction tube is heated from room temperature to 1300±10℃ at a heating rate of 5-8℃ / min, and the temperature of the lower part of the reaction tube is maintained at 1300±10℃. After the upper reaction is completed, heating is stopped.

[0031] 9) After the device has cooled down, take out the coke sample, weigh the coke after the reaction, and record its mass as m1 in g. The coke reactivity CRI is calculated according to the following formula (1):

[0032]

[0033] The post-reaction strength (CSR) of coke is calculated according to formula (2):

[0034]

[0035] Where: m2 is the mass of coke particles larger than 10mm after the reaction and the remaining coke after the drum is turned, in g.

[0036] The reactivity and post-reaction strength of coke were tested three times, and the results were taken as the arithmetic mean of parallel tests.

[0037] The drying temperature in step 1) above is 170-180℃, and the drying time is 2±0.05h.

[0038] In step 2) above, the purity of sodium carbonate is >99.8%, the purity of potassium carbonate is >99.0%, and the activated carbon powder is an analytical grade sample.

[0039] Compared with existing technologies, the beneficial effects of this invention are:

[0040] In this invention, the temperatures of the upper and lower heating elements in the coke quality evaluation device simulating a blast furnace environment are controlled independently. The adjustable temperature range for the upper element is 0-1600℃, and for the lower element, it is 0-1400℃. Furthermore, the device includes a pressurizing unit at the top to simulate the static pressure exerted on the coke by the upper material within the blast furnace. An automatically lifting device is installed at the bottom, which holds activated carbon powder and sodium carbonate or potassium carbonate to provide an alkali metal reducing atmosphere to the upper element. Therefore, this blast furnace environment simulation device more closely resembles the actual state of coke in a blast furnace, including high temperature, carbon dioxide atmosphere, circulating alkali metal atmosphere, and pressure from the burden column. The reaction process using this device allows for a more realistic, objective, and reasonable evaluation of coke quality, providing better guidance for actual production. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of the evaluation device for simulating coke quality under blast furnace conditions according to the present invention.

[0042] In the diagram: 1. Pressurizing device, 2. Air inlet, 3. Upper flange, 4. Reaction tube, 5. Upper heating element, 6. Insulation layer, 7. Thermocouple, 8. Material, 9. Sieve plate, 10. Reactor body, 11. Lower flange, 12. Air inlet, 13. Lifting device, 14. Vessel disc, 15. Upper heating element, 16. Reactor control device. Detailed Implementation

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are merely illustrative and are not intended to limit the present invention.

[0044] like Figure 1As shown, an evaluation device simulating coke quality under blast furnace conditions includes a reactor body 10, a reaction tube 4, a vessel disc 14, a lifting device 13, and a pressurizing device 1. The reaction tube 4 is disposed inside the reactor body 10, and a perforated sieve plate 9 is fixed in the middle of the reaction tube 4. The upper and lower ends of the reaction tube 4 are sealed by flanges. The lifting device 13 is disposed at the lower part of the reaction tube 4 and can drive the vessel disc 14 to move up and down inside the reaction tube 4. The pressurizing device 1 is disposed at the upper part of the reaction tube 4 and can apply pressure to the material placed on the upper end of the sieve plate 9. The reaction tube 4 also has an air inlet 12 and an air outlet 2. A thermocouple 7 is also included, which is inserted into the material inside the reaction tube 4 from the upper end of the reaction tube 4.

[0045] In the reactor body 10, heating elements are arranged in two sections along the longitudinal direction of the reaction tube 4: the upper heating element 5 is used to heat the material on the sieve plate 9, and the lower heating element 15 is used to heat the material on the vessel disc 14. The reactor body 10 is surrounded by an insulation layer 6, and thermocouples 7 are installed inside the furnace wall.

[0046] The heating temperature of the upper heating element 5 is 900℃-1600℃, and the heating temperature of the lower heating element 15 is 700℃-1400℃.

[0047] A method for determining coke quality using an evaluation device simulating a blast furnace environment includes the following steps:

[0048] 1) Crush the coke with a jaw crusher, discard the flaky and strip-shaped coke blocks, and manually grind the remaining coke into granular coke samples of 23mm-25mm. Place the prepared granular coke samples into a drying oven, take out the coke, cool it to room temperature, weigh it for later use, and record the mass as m, with the unit being g.

[0049] 2) Open the flange (lower flange 11) at the lower end of the reaction tube 4 and place the activated carbon powder and sodium carbonate or potassium carbonate on the container disc 14 that can be raised and lowered.

[0050] 3) Open the flange at the upper end of the reaction tube 4 (upper flange 3), spread the coke cooled to room temperature on the sieve plate 9 in the middle of the reaction tube 4, and close the upper flange 3.

[0051] 4) Insert the temperature measuring thermocouple 7 through the thermocouple sleeve set in the reaction tube 4 into the center of the material layer on the sieve plate 9.

[0052] 5) Connect the reactor's inlet and outlet pipes to the gas supply and exhaust systems respectively, check the gas path, and ensure it is tight;

[0053] 6) The upper pressurization device 1 applies a pressure of 10±0.1Kpa and heats the upper part of the reaction tube 4 from room temperature to 500℃ at a heating rate of 5~8℃ / min; when the temperature of the center of the material layer reaches 500±5℃, nitrogen is introduced at a flow rate of 0.8±0.05L / min to protect the coke from burning.

[0054] The heating rate from 500℃ to 900℃ is 3-5℃ / min, and nitrogen gas is continuously passed through at a flow rate of 0.8±0.05L / min.

[0055] The heating rate from 900℃ to 1300℃ is 2~3℃ / min. When the center temperature of the material layer on the sieve plate 9 reaches 1300±5℃, the nitrogen gas is cut off after stabilizing for 10±0.5min, and carbon dioxide is introduced instead, with a carbon dioxide flow rate of 5±0.1L / min.

[0056] 7) Continue heating the upper part of reaction tube 4 to 1500±10℃, maintain the temperature at 1500±10℃ for 2±0.05h, stop heating, cut off the carbon dioxide gas line, switch to nitrogen gas, and control the flow rate at 2±0.1L / min.

[0057] 8) When the upper part of the reaction tube 4 is heated to 300±10℃, the container disk 14 containing activated carbon powder and sodium carbonate or potassium carbonate sample is raised to a distance of 3±0.2cm from the middle sieve plate; the lower part of the reaction tube 4 is heated from room temperature to 1300±10℃ at a heating rate of 5-8℃ / min, and the temperature of the lower part of the reaction tube 4 is maintained at 1300±10℃. After the upper reaction is completed, the heating is stopped.

[0058] 9) After the device has cooled down, take out the coke sample, weigh the coke after the reaction, and record its mass as m1 in g. The coke reactivity CRI is calculated according to the following formula (1):

[0059]

[0060] The post-reaction strength (CSR) of coke is calculated according to formula (2):

[0061]

[0062] Where: m2 is the mass of coke particles larger than 10mm after the reaction and the remaining coke after the drum is turned, in g.

[0063] The reactivity and post-reaction strength of coke were tested three times, and the results were taken as the arithmetic mean of parallel tests.

[0064] The drying temperature in step 1) above is 170-180℃, and the drying time is 2±0.05h.

[0065] In step 2) above, the purity of sodium carbonate is >99.8%, the purity of potassium carbonate is >99.0%, and the activated carbon powder is an analytical grade sample.

[0066] The atmosphere and temperature data provided and collected by this invention can be programmed and stored as curve data, which can be called and used at any time as needed, and supports the recording and adjustment of parameters such as temperature and atmosphere.

[0067] The air inlet 12, lower flange 11, air outlet 2 and upper flange 3 constitute a gas circulation system. Different gas cylinders are selected according to the experimental atmosphere, and the gas cylinders are connected to the air inlet using hoses to provide the corresponding atmosphere for the experiment.

[0068] The upper heating element 5 and the lower heating element 15 constitute an automatic heating system. The heating element adopts a U-shaped silicon molybdenum rod. The heating range of the upper heating element 5 is 0-1600℃, and the heating range of the lower heating element 15 is 0-1400℃.

[0069] Reaction tube 4 is an alumina tube, which can be designed in two sections: an upper section with a smaller inner diameter and a lower section with a larger inner diameter. The upper section can be placed on top of the lower section, and its end has a perforated sieve plate to facilitate gas passage while preventing the falling of coke material. Reaction tube 4 can accommodate experiments in various atmospheres, including N2, H2O, CO2, K, and Na.

[0070] The upper pressurization device 1 can apply a certain static pressure to the reactants, simulating the static pressure of the upper material on the material in the blast furnace.

[0071] By controlling the height of the lifting device 1, the height of the disc vessel 14 placed on the lifting device 1 can be adjusted. The disc vessel 14 can be filled with materials that provide an alkali metal atmosphere. After being placed according to the required reaction ratio, the distance between the lifting device 13 and the upper material can be controlled. After the heating reaction, an alkali metal reducing atmosphere is provided to the upper coke.

[0072] Thermocouple sleeves can be connected to the upper flange 3 and the bottom pressure plate of the pressurizing device 1 to insert thermocouple 7 from the upper flange into the center of the coke material to directly measure the temperature of the reaction material. Thermocouple 7 on the side of the furnace wall of the reaction furnace body 10 measures the temperature of the upper heating and the temperature of the lower heating respectively.

[0073] The insulation layer 6 is made of alumina hollow sphere bricks, lightweight high-alumina bricks, and aluminum silicate refractory fibers.

[0074] Thermocouple 7 uses a double platinum-rhodium thermocouple for temperature measurement and control.

[0075] Example:

[0076] 1. Different types of metallurgical coke were selected for experiments. A jaw crusher was used to crush the coke, removing strip-shaped and flaky coke, and grinding it into spherical coke particles with a diameter of 20-25 mm. The mass of each particle was recorded. The coke was dried in a drying oven at 175℃ for 2 hours, and then cooled to room temperature.

[0077] 2. Add different masses of potassium carbonate sample or sodium carbonate and activated carbon powder according to different coke, and place the potassium carbonate sample or sodium carbonate and activated carbon powder into a movable container disc 14. Place the dried coke from step 1 onto the sieve plate 9 in the reaction tube 7 and insert the thermocouple 7.

[0078] 3. Proceed with the heating program as set. Connect the power supply, start the device, apply a pressure of 10 kPa to the upper pressurizing device 1, and turn on the upper heating element 5 to heat from room temperature to 500°C at a rate of 7°C / min. When the center temperature of the material layer reaches 500°C, purge with nitrogen at a flow rate of 0.8 L / min to protect the coke from further burn-out. When heating from 500°C to 900°C, the heating rate is 4°C / min, and nitrogen continues to purge at a flow rate of 0.8 L / min. When heating from 900°C to 1300°C, the heating rate is 3°C / min. When the center temperature of the material layer reaches 1300°C, stabilize for 10 minutes, then cut off the nitrogen supply and switch to carbon dioxide at a flow rate of 5 L / min.

[0079] Continue heating the upper part to 1500℃, maintain the temperature at 1500℃ for 2 hours, then stop heating, cut off the carbon dioxide gas line, and switch to nitrogen gas with a flow rate of 2L / min.

[0080] When the upper device is heated to 300℃, the vessel disc is raised to 3cm above the sieve plate using a lifting device. The lower device is then heated from room temperature to 1300℃ at a rate of 6℃ / min. The temperature of the lower device is maintained at 1300℃. Heating is stopped after the upper reaction is complete.

[0081] 4. After the coke has cooled, remove it and weigh the mass of the coke after the reaction. Measure the reactivity CRI and post-reaction strength CSR of different cokes in each experimental example under different alkaline conditions, as shown in Table 1.

[0082] Table 1. Reactivity CRI and Post-Reaction Strength CSR of Coke under Alkaline Conditions in Each Experimental Example

[0083]

[0084] Note: The percentage content in Table 1 is the mass ratio of alkali metal vapor K or Na to coke. 1% K, 3% K, 1% Na, and 3% Na are used to simulate different alkali metal vapor contents in the blast furnace.

[0085] From the perspective of traditional coke evaluation, the quality of coke1 is worse than that of coke2. However, according to the evaluation method of the device of this invention, in the presence of alkali metals, the actual effects of coke1 and coke2 in the blast furnace are not significantly different.

[0086] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for determining the quality of coke under simulated blast furnace conditions, characterized in that, The apparatus includes a reactor body, a reaction tube, a vessel disc, a lifting device, and a pressurizing device. The reaction tube is located inside the reactor body, and a perforated sieve plate is fixed in the middle of the reaction tube. The upper and lower ends of the reaction tube are sealed by flanges. The lifting device is located at the lower part of the reaction tube and can drive the vessel disc to move up and down inside the reaction tube. The pressurizing device is located at the upper part of the reaction tube and can apply pressure to the material placed on the upper part of the sieve plate. The reaction tube is also provided with an air inlet and an air outlet. The methods and steps include the following: 1) Crush the coke, discard the flake and strip coke blocks, and grind the remaining coke into granular coke samples with a diameter of 23mm-25mm. Dry the prepared granular coke samples, cool them, weigh them for later use, and record the mass as m. 2) Place activated carbon powder and sodium carbonate or potassium carbonate on a movable disc; spread cooled coke on the sieve plate in the middle of the reaction tube; 3) Insert the temperature measuring thermocouple through the thermocouple sheath set in the reaction tube into the center of the material layer on the sieve plate; 4) The upper pressurization device applies a pressure of 10±0.1Kpa and heats the upper part of the reaction tube from room temperature to 500℃ at a rate of 5~8℃ / min; when the temperature at the center of the material layer reaches 500±5℃, nitrogen is introduced at a flow rate of 0.8±0.05L / min. The heating rate from 500℃ to 900℃ is 3-5℃ / min, and nitrogen gas is continuously passed through at a flow rate of 0.8±0.05L / min. The heating rate from 900℃ to 1300℃ is 2-3℃ / min. When the center temperature of the material layer on the sieve plate reaches 1300±5℃, stabilize for 10±0.5min, cut off the nitrogen gas, and switch to carbon dioxide with a flow rate of 5±0.1L / min. 5) Continue to raise the temperature of the upper part of the reaction tube to 1500±10℃, with a heating rate of 2~3℃ / min; maintain the temperature at 1500±10℃ for 2±0.05h, stop heating, cut off the carbon dioxide gas line, switch to nitrogen gas, and control the flow rate at 2±0.1L / min. 6) When the upper part of the reaction tube is heated to 300±10℃, raise the glass dish containing activated carbon powder and sodium carbonate or potassium carbonate sample to a distance of 3±0.2cm from the middle sieve plate; start heating the lower part of the reaction tube from room temperature to 1300±10℃ at a heating rate of 5-8℃ / min, maintain the temperature of the lower part of the reaction tube at 1300±10℃, and stop heating after the upper reaction is completed; 7) After the device has cooled down, take out the coke sample, weigh the mass of the coke after the reaction, record the mass as m1, and calculate the reactivity CRI and the strength CSR of the coke under alkaline conditions.

2. The method for determining coke quality under simulated blast furnace conditions according to claim 1, characterized in that, In the reactor body, heating elements are arranged in two sections along the longitudinal direction of the reaction tube. The upper heating element is used to heat the material on the sieve plate, and the lower heating element is used to heat the material on the vessel disc.

3. The method for determining coke quality under simulated blast furnace conditions according to claim 2, characterized in that, The outer side of the reactor body is an insulation layer, and thermocouples are installed inside the furnace wall.

4. The method for determining the quality of coke under simulated blast furnace conditions according to claim 2, characterized in that, The heating temperature of the upper heating element is 0℃-1600℃, and the heating temperature of the lower heating element is 0℃-1400℃.

5. The method for determining coke quality under simulated blast furnace conditions according to claim 1, characterized in that, It also includes thermocouples, which are inserted into the material in the reaction tube from the top end of the reaction tube.

6. The method for determining coke quality under simulated blast furnace conditions according to claim 1, characterized in that, The drying temperature in step 1) above is 170-180℃, and the drying time is 2±0.05h.

7. The method for determining coke quality under simulated blast furnace conditions according to claim 1, characterized in that, In step 2) above, the purity of sodium carbonate is >99.8%, the purity of potassium carbonate is >99.0%, and the activated carbon powder is an analytical grade sample.

8. The method for determining the quality of coke under simulated blast furnace conditions according to claim 1, characterized in that, Step 7) above, the coke reactivity CRI is calculated according to the following formula (1): -------(1) The post-reaction strength (CSR) of coke is calculated according to formula (2): --------(2) in: The mass of coke particles larger than 10 mm remaining after the reaction and after the drum is turned.

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