A kind of iron molybdenum hydrogenation catalyst carbon burning regeneration anti-temperature rising control system and method

Abstract

The application discloses a kind of iron molybdenum hydrogenation catalyst carbon burning regeneration anti-flying temperature control system and method, including nitrogen gas supply unit, compressed air supply unit, gas mixer, preheater, hydrogenation reactor, temperature monitoring component, tail gas purification unit and PLC automatic control unit, the beneficial effects of the present application are that precise oxygen structure and distributed temperature monitoring are used, cooperating with PLC automatic interlock control, realize the precise regulation and control of carbon burning process temperature and oxygen concentration, effectively inhibit the local temperature of bed layer and avoid catalyst sintering and active phase loss, the activity recovery rate of regenerated catalyst is greater than or equal to 85%; The device realizes in-situ regeneration, without disassembling catalyst, greatly shortens the regeneration cycle, reduces construction cost, and the regeneration cost is reduced by more than 60% compared with replacing new catalyst, which effectively reduces enterprise production cost.

Description

Technical Field

[0001] This invention relates to the field of chemical catalytic regeneration, specifically to a temperature control system and method for preventing overheating during the carbonization regeneration of iron-molybdenum hydrogenation catalysts. Background Technology

[0002] Iron-molybdenum based hydrogenation catalysts are core catalytic materials in the hydrogenation and desulfurization processes of feedstock gas in coal chemical and natural gas chemical industries. They are mainly used to hydrogenate organic sulfur compounds such as COS, CS2, and thiophene in feedstock gas into easily removable hydrogen sulfide, while saturating unsaturated hydrocarbons in the feedstock gas. This effectively protects the catalysts in subsequent processes such as methanol synthesis and methanation from sulfur poisoning and carbon buildup, ensuring the long-term stable operation of the equipment.

[0003] During long-term continuous industrial operation, impurities such as tar, benzene compounds, and heavy hydrocarbons in the feed gas can easily cause hydrocarbon cracking and condensation side reactions on the catalyst surface and in the micropores, gradually generating and continuously depositing coke. This leads to the covering of catalyst active sites, pore blockage, and a significant decrease in specific surface area, ultimately resulting in problems such as reduced hydrodesulfurization conversion rate, increased reactor bed pressure difference, and limited unit production load, causing catalyst deactivation. Directly replacing the deactivated catalyst is not only costly in terms of procurement but also creates hazardous waste disposal pressure. Furthermore, frequent shutdowns for replacement severely impact the continuous production efficiency of the unit, increasing the company's production costs.

[0004] Currently, the mainstream industrial method for regenerating deactivated iron-molybdenum hydrogenation catalysts by burning carbon deposits with compressed air is in-situ regeneration. This technology uses oxygen at high temperatures to oxidize the carbon deposits, thereby removing them and restoring catalyst activity. However, existing traditional carbon burning regeneration processes and equipment have several technical defects: First, the gas supply system lacks a precise oxygen distribution structure, resulting in poor oxygen concentration regulation and a tendency for localized excessive oxygen content, leading to localized overheating of the bed, catalyst sintering, loss of active phase, and complete catalyst destruction. Second, temperature monitoring coverage is incomplete, making it impossible to accurately control the temperature of the entire catalyst bed in real time, resulting in strong temperature control lag. Third, the carbon burning exhaust gas contains toxic and harmful gases such as SO2 and CO, which, if directly emitted, will cause environmental pollution and pose safety hazards. Fourth, the equipment has a low degree of automation, relying on manual operation and control, resulting in large operational errors and high safety risks. Summary of the Invention

[0005] In order to overcome the problems of the prior art, the present invention provides a temperature control system and method for preventing overheating during the carbonization regeneration of iron-molybdenum hydrogenation catalysts.

[0006] The technical solution adopted by this invention to solve its technical problem is: a temperature runaway control system for the carbonization regeneration of iron-molybdenum hydrogenation catalyst, comprising a nitrogen supply unit, a compressed air supply unit, a gas mixer, a preheater, a hydrogenation reactor, a temperature monitoring component, a tail gas purification unit, and a PLC automatic control unit. The outlets of the nitrogen supply unit and the compressed air supply unit are both connected to the inlet of the gas mixer. The outlet of the gas mixer is connected to the preheater, the hydrogenation reactor, and the tail gas purification unit in sequence through pipelines, forming a closed regeneration pipeline system. The temperature monitoring component is arranged in the catalyst bed inside the hydrogenation reactor. The PLC automatic control unit is electrically interlocked with the temperature monitoring component, the nitrogen supply unit, the compressed air supply unit, and the preheater. The PLC automatic control unit has a built-in temperature runaway control module, which is based on the temperature data fed back by the temperature monitoring component and has a primary early warning mechanism and a secondary protection mechanism.

[0007] The aforementioned anti-overheating control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst includes a nitrogen supply unit comprising a nitrogen storage tank, a pressure regulating valve, and a nitrogen flow regulating valve, wherein the pressure regulating valve and the nitrogen flow regulating valve are connected in series in the outlet pipe of the nitrogen storage tank. The compressed air supply unit includes an air compressor, a dryer filter, and an oxygen concentration regulating valve, wherein the dryer filter and the oxygen concentration regulating valve are connected in series in the outlet pipe of the air compressor.

[0008] The aforementioned anti-overheating control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst includes a built-in diversion stirring blade inside the gas mixer.

[0009] The above-mentioned anti-overheating control system for the carbonization regeneration of iron-molybdenum hydrogenation catalyst includes a temperature monitoring component comprising multiple sets of axially distributed temperature sensors. These multiple sets of temperature sensors are evenly distributed along the upper, middle, and lower sections of the catalyst bed in the hydrogenation reactor, with at least three sets of temperature sensors distributed in each section.

[0010] The aforementioned anti-overheating control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst includes a primary warning mechanism and a secondary protection mechanism in the PLC automatic control unit. The primary warning mechanism automatically triggers an audible and visual alarm when the highest bed temperature detected by the temperature monitoring component reaches or exceeds 430℃, the bed heating rate reaches or exceeds 15℃ / h, or the temperature difference between different sections of the bed reaches or exceeds 20℃. It also reduces the opening of the oxygen concentration regulating valve and increases the opening of the nitrogen flow regulating valve. After waiting for a preset response time, it determines whether to lift the warning based on the temperature drop. The secondary protection mechanism automatically performs an emergency cut-off when the highest bed temperature detected by the temperature monitoring component reaches or exceeds 460℃ or the bed heating rate reaches or exceeds 20℃ / h. This involves shutting off the oxygen concentration regulating valve and the power supply to the preheater, fully opening the nitrogen flow regulating valve for forced nitrogen purging, and triggering an emergency audible and visual alarm.

[0011] The above-mentioned anti-overheating control system for the carbon regeneration of iron-molybdenum hydrogenation catalyst includes a tail gas purification unit consisting of a desulfurization absorption tower, an activated carbon adsorber, and a flue gas cooler connected in series. The desulfurization absorption tower is filled with an alkaline absorption medium.

[0012] The above-mentioned anti-overheating control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst maintains a slight positive pressure of 0.02~0.05MPa during operation of the closed regeneration pipeline system. The catalyst bed temperature is controlled within the range of 300~450℃ during carbonization, and the oxygen concentration of the mixed gas is regulated within the range of 0.5%~5%.

[0013] A method for preventing runaway temperature during the carbonization regeneration of an iron-molybdenum hydrogenation catalyst includes the following steps:

[0014] Step 1: Introduce high-purity nitrogen into the closed regeneration pipeline system to replace the combustible gas in the system and reduce the concentration of combustible gas to below the safe threshold.

[0015] Step 2: Under a nitrogen protective atmosphere, start the preheater and preheat the catalyst bed in the hydrogenation reactor to the initial carbonization temperature at the set heating rate.

[0016] Step 3: Mix nitrogen and compressed air in a certain proportion using a gas mixer, and introduce the mixture into the hydrogenation reactor with an initial low oxygen concentration. Gradually increase the oxygen concentration of the mixed gas according to the carbonization process, and oxidize and carbonize the catalyst under controllable temperature and oxygen concentration conditions.

[0017] Step 4: During the charcoal burning process, the PLC automatic control unit reads the temperature of each measuring point in the catalyst bed in real time through the temperature monitoring component, calculates the maximum temperature of the bed, the heating rate and the temperature difference of each section, and automatically adjusts the oxygen concentration, nitrogen flow rate and heating power according to the built-in first-level early warning mechanism and the second-level protection mechanism to prevent local overheating of the bed.

[0018] Step 5: Monitor the CO and CO2 concentrations in the tail gas at the outlet of the hydrogenation reactor in real time. When the CO and CO2 concentrations are continuously lower than the preset threshold and remain below the preset time, it is determined that the carbon deposit burn-off is complete.

[0019] Step 6: Cut off the compressed air and shut down the preheater, keep nitrogen purging, reduce the bed temperature to no more than 50°C according to the set cooling rate, and treat the exhaust gas generated throughout the charcoal burning process through the exhaust gas purification unit to meet the emission standards.

[0020] The above-mentioned method for preventing runaway temperature during the carbonization regeneration of iron-molybdenum hydrogenation catalyst, specifically the logic of the runaway temperature control in step 4, is as follows:

[0021] When the first-level warning conditions are met, the PLC automatic control unit issues an audible and visual alarm, reduces the opening of the oxygen concentration regulating valve by 20%, increases the opening of the nitrogen flow regulating valve by 15%, waits for a preset response time, and then determines whether the bed temperature has dropped back to a safe range. If it has dropped back, normal operation is restored; if it has not dropped back, the second-level protection mechanism is triggered.

[0022] When the secondary protection conditions are met, the PLC automatic control unit performs an emergency shutdown, closes the oxygen concentration regulating valve, shuts off the power supply to the preheater, fully opens the nitrogen flow regulating valve, issues an emergency audible and visual alarm to prompt manual intervention, and uses nitrogen to force-purge and cool down until the highest bed temperature drops below 100°C, and then safely shuts down.

[0023] In the above-mentioned method for preventing runaway temperature during the carbonization regeneration of the iron-molybdenum hydrogenation catalyst, the preset threshold in step 5 is 50 ppm, the set duration is 60 min, and the set cooling rate in step 6 is no more than 30 °C / h.

[0024] The beneficial effects of this invention are

[0025] 1. Employing a precise oxygen distribution structure and distributed temperature monitoring, coupled with PLC automatic interlock control, the system achieves precise regulation of temperature and oxygen concentration during the charcoal combustion process. This effectively suppresses localized overheating in the bed, prevents catalyst sintering and active phase loss, and ensures a catalyst activity recovery rate of ≥85% after regeneration. 2. The system enables in-situ regeneration without disassembly or unloading, significantly shortening the regeneration cycle and reducing construction costs. Regeneration costs are more than 60% lower than replacing the catalyst, effectively reducing enterprise production costs. 3. Equipped with a closed-loop tail gas purification unit, the system efficiently treats toxic and harmful gases in the charcoal combustion tail gas, preventing gas leakage pollution, meeting environmental protection production requirements, and eliminating safety hazards. 4. The system boasts a high degree of automation, reducing human error, improving the stability and safety of the charcoal combustion regeneration process, and adapting to the needs of continuous industrial production. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] Figure 1 This is a schematic diagram showing the structural composition and control signal connection of the anti-flying temperature control system described in this invention;

[0028] Figure 2 This is a flowchart of the charcoal regeneration process of the anti-flying temperature control method described in this invention;

[0029] Figure 3 This is a flowchart of the anti-overheating control logic of the PLC automatic control unit described in this invention. Detailed Implementation

[0030] The following is combined Figure 1 , Figure 2 , Figure 3 The technical solution of the present invention will be further described in detail below with reference to the embodiments.

[0031] Example 1

[0032] A temperature control system and method for preventing runaway temperatures during the carbonization regeneration of iron-molybdenum hydrogenation catalyst;

[0033] The anti-runaway temperature control system includes a nitrogen supply unit, a compressed air supply unit, a gas mixer, a preheater, a hydrogenation reactor, a temperature monitoring component, an exhaust gas purification unit, and a PLC automatic control unit.

[0034] The nitrogen supply unit uses a 5m³ nitrogen storage tank, equipped with a pressure stabilizing valve and a nitrogen flow regulating valve. The compressed air supply unit uses a screw air compressor with a discharge volume of 6m³ / min and a discharge pressure of 0.8MPa. The rear end is connected to a dryer filter and an oxygen concentration regulating valve.

[0035] The two pipelines converge and connect to a gas mixer. The gas mixer has built-in stainless steel diversion stirring blades. The gas outlet of the gas mixer is connected to an electric heating preheater. The outlet of the preheater is connected to the feed inlet of the hydrogenation reactor. The hydrogenation reactor is equipped with three sets of PT100 temperature sensors each along the upper, middle and lower sections of the catalyst bed, for a total of nine temperature measurement points. The sensor signal lines are connected to the PLC automatic control unit. The reactor outlet is connected in sequence to the desulfurization absorption tower (filled with 20% NaOH alkaline solution), the activated carbon adsorber, and the flue gas cooler, and finally to the exhaust stack.

[0036] Open the nitrogen storage tank valve, adjust the pressure regulating valve, and introduce high-purity nitrogen (purity ≥99.99%) into the entire system. Purge continuously for 45 minutes, and use a combustible gas detector to detect the concentration of combustible gas in the system until the combustible gas content is ≤0.5%. Then close the exhaust valve to complete the system replacement.

[0037] Keep nitrogen flowing continuously, turn on the preheater, set the heating rate to 15℃ / h through the PLC automatic control unit, and uniformly raise the temperature of the catalyst bed to 320℃. Wait until the temperature of each point in the bed is stable and without fluctuation (temperature difference between each measuring point ≤5℃).

[0038] Compressed air intake was initiated via a PLC automatic control unit, initially adjusting the oxygen concentration to 0.8% before being introduced into the hydrogenation reactor. Real-time monitoring of nine temperature measurement points on the bed was conducted, with the oxygen concentration increased by 0.5% every 30 minutes, gradually reaching 3.5%. The bed temperature was maintained consistently between 400 and 430°C throughout the process, with a maximum temperature difference of ≤10°C between measurement points. The highest recorded hot spot temperature was 442°C, below the safety threshold of 460°C. No localized hot spots occurred during the charcoal combustion process.

[0039] Continuously monitor the CO and CO2 concentrations in the outlet gas of the hydrogenation reactor. When the CO and CO2 concentrations remain below 50 ppm for more than 60 minutes, the carbon deposit removal is considered complete.

[0040] During the charcoal burning process, when the bed temperature reaches the first preset threshold of 430℃, the PLC automatic control unit issues an audible and visual alarm signal and automatically reduces the opening of the oxygen concentration regulating valve by 20%, while increasing the nitrogen flow rate by 15%; in this embodiment, the emergency cut-off protection at the second preset threshold of 460℃ is not triggered.

[0041] After the charcoal burning endpoint is determined, the PLC automatic control unit immediately executes the safety interlock response, automatically cuts off the compressed air, shuts down the preheater, maintains continuous nitrogen purging, sets the cooling rate to 25℃ / h, and reduces the bed temperature to no higher than 50℃; after the cooling is completed, nitrogen is used to purge and replace the residual gas in the system for 30 minutes.

[0042] The exhaust gas generated throughout the charcoal burning process is treated by a desulfurization absorption tower to remove SO2 (removal rate ≥98%) and an activated carbon adsorber. After the gas is purified, the SO2 content is measured to be ≤10ppm and the CO content to be ≤15ppm by a flue gas analyzer. Once the gas meets the standards, it is discharged through a chimney.

[0043] After regeneration, catalyst samples were taken for testing:

[0044] Catalyst appearance: No sintering, pulverization, or agglomeration; particles are intact.

[0045] Specific surface area recovery rate: The specific surface area of ​​the catalyst before regeneration was 68 m² / g, and after regeneration it was 186 m² / g, recovering to 90.7% of that of the fresh catalyst (205 m² / g).

[0046] The hydrodesulfurization activity recovery rate reaches 88%, meeting the requirements for industrial production.

[0047] Bed pressure differential: It recovered from 0.15MPa before regeneration to 0.02MPa, close to the initial operating state.

[0048] Example 2

[0049] The catalyst being treated was another batch of iron-molybdenum hydrogenation catalyst with a higher degree of coking (bed pressure difference 0.20 MPa), with a coking amount of approximately 8.5 wt% of the fresh catalyst.

[0050] To prevent overheating caused by the intense exothermic process during high-coke-density charcoal burning, this embodiment employs a more stringent overheating prevention control strategy:

[0051] A two-stage heating method was adopted, with a rate of 10℃ / h below 100℃ and a rate of 15℃ / h from 100℃ to 320℃. The total preheating time was extended by 4 hours compared to Example 1 to ensure uniform bed temperature.

[0052] The initial oxygen concentration was 0.5%, and the increase was 0.3% each time (lower than 0.5% in Example 1). The interval between two adjacent increases was extended to 45 minutes, and the total charcoal burning cycle was extended from 8 hours in Example 1 to 12 hours.

[0053] The warning temperature threshold is set at 430℃, and the safety protection threshold is set at 460℃, consistent with Example 1.

[0054] During implementation, when the bed temperature rise rate exceeded 15℃ / h, a level one early warning mechanism was triggered. The PLC automatic control unit issued an audible and visual alarm, automatically reduced the opening of the oxygen concentration regulating valve by 20%, and simultaneously increased the opening of the nitrogen flow regulating valve by 15%. After waiting for the preset response time, the bed temperature changed from an upward trend to a stable state, with the highest recorded temperature being 438℃. The level two emergency shut-off at 460℃ was not triggered, and the system returned to normal operation. After regeneration, the catalyst activity recovery rate reached 86%, and the bed pressure difference dropped to 0.03MPa, indicating a good regeneration effect.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A temperature runaway control system for the carbonization regeneration of an iron-molybdenum hydrogenation catalyst, characterized in that, The system includes a nitrogen supply unit, a compressed air supply unit, a gas mixer, a preheater, a hydrogenation reactor, a temperature monitoring component, an exhaust gas purification unit, and a PLC automatic control unit. The outlets of the nitrogen supply unit and the compressed air supply unit are both connected to the inlet of the gas mixer. The outlet of the gas mixer is connected to the preheater, the hydrogenation reactor, and the exhaust gas purification unit in sequence through pipelines, forming a closed regeneration pipeline system. The temperature monitoring component is installed in the catalyst bed inside the hydrogenation reactor. The PLC automatic control unit is electrically interlocked with the temperature monitoring component, the nitrogen supply unit, the compressed air supply unit, and the preheater. The PLC automatic control unit has a built-in anti-overheating control module, which is based on the temperature data fed back by the temperature monitoring component and has a primary early warning mechanism and a secondary protection mechanism.

2. The anti-runaway temperature control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 1, characterized in that, The nitrogen supply unit includes a nitrogen storage tank, a pressure regulating valve, and a nitrogen flow regulating valve. The pressure regulating valve and the nitrogen flow regulating valve are connected in series in the outlet pipe of the nitrogen storage tank. The compressed air supply unit includes an air compressor, a dryer filter, and an oxygen concentration regulating valve. The dryer filter and the oxygen concentration regulating valve are connected in series in the outlet pipe of the air compressor.

3. The anti-runaway temperature control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 1, characterized in that, The gas mixer has built-in flow-diverting stirring blades.

4. The anti-runaway temperature control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 1, characterized in that, The temperature monitoring component includes multiple sets of axially distributed temperature sensors, which are evenly distributed along the upper, middle and lower sections of the catalyst bed in the hydrogenation reactor, with at least three sets of temperature sensors distributed in each section.

5. The anti-runaway temperature control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 1, characterized in that, The anti-overheating control module of the PLC automatic control unit includes a primary early warning mechanism and a secondary protection mechanism. The primary early warning mechanism automatically triggers an audible and visual alarm when the highest bed temperature detected by the temperature monitoring component reaches or exceeds 430℃, the bed heating rate reaches or exceeds 15℃ / h, or the temperature difference between different sections of the bed reaches or exceeds 20℃. It also reduces the opening of the oxygen concentration regulating valve and increases the opening of the nitrogen flow regulating valve. After waiting for a preset response time, it determines whether to lift the warning based on the temperature drop. The secondary protection mechanism automatically performs an emergency shutdown when the highest bed temperature detected by the temperature monitoring component reaches or exceeds 460℃ or the bed heating rate reaches or exceeds 20℃ / h. It shuts off the oxygen concentration regulating valve and the power supply to the preheater, fully opens the nitrogen flow regulating valve for forced nitrogen purging, and triggers an emergency audible and visual alarm. The preset response time is 5 to 15 minutes.

6. The anti-runaway temperature control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 1, characterized in that, The exhaust gas purification unit consists of a desulfurization absorption tower, an activated carbon adsorber, and a flue gas cooler connected in series. The desulfurization absorption tower is filled with an alkaline absorption medium.

7. The anti-runaway temperature control system for the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 1, characterized in that, The closed regeneration pipeline system maintains a slight positive pressure of 0.02~0.05MPa during operation. The catalyst bed temperature is controlled within the range of 300~450℃ during charcoal burning, and the oxygen concentration of the mixed gas is regulated within the range of 0.5%~5%.

8. A method for preventing runaway temperature during the carbonization regeneration of an iron-molybdenum hydrogenation catalyst, based on the anti-runaway temperature control system for the carbonization regeneration of an iron-molybdenum hydrogenation catalyst according to any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Introduce high-purity nitrogen into the closed regeneration pipeline system to replace the combustible gas in the system and reduce the concentration of combustible gas to below the safe threshold. Step 2: Under a nitrogen protective atmosphere, start the preheater and preheat the catalyst bed in the hydrogenation reactor to the initial carbonization temperature at the set heating rate. Step 3: Mix nitrogen and compressed air in a certain proportion using a gas mixer, and introduce the mixture into the hydrogenation reactor with an initial low oxygen concentration. Gradually increase the oxygen concentration of the mixed gas according to the carbonization process, and oxidize and carbonize the catalyst under controllable temperature and oxygen concentration conditions. Step 4: During the charcoal burning process, the PLC automatic control unit reads the temperature of each measuring point in the catalyst bed in real time through the temperature monitoring component, calculates the maximum temperature of the bed, the heating rate and the temperature difference of each section, and automatically adjusts the oxygen concentration, nitrogen flow rate and heating power according to the built-in first-level early warning mechanism and the second-level protection mechanism to prevent local overheating of the bed. Step 5: Monitor the CO and CO2 concentrations in the tail gas at the outlet of the hydrogenation reactor in real time. When the CO and CO2 concentrations are continuously lower than the preset threshold and remain below the preset time, it is determined that the carbon deposit burn-off is complete. Step 6: Cut off the compressed air and shut down the preheater, keep nitrogen purging, reduce the bed temperature to no more than 50°C according to the set cooling rate, and treat the exhaust gas generated throughout the charcoal burning process through the exhaust gas purification unit to meet the emission standards.

9. The method for preventing runaway temperature during the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 8, characterized in that, The specific logic for the anti-overheating control in step 4 is as follows: When the first-level warning conditions are met, the PLC automatic control unit issues an audible and visual alarm, reduces the opening of the oxygen concentration regulating valve by 20%, increases the opening of the nitrogen flow regulating valve by 15%, waits for a preset response time, and then determines whether the bed temperature has dropped back to a safe range. If it has dropped back, normal operation is restored; if it has not dropped back, the second-level protection mechanism is triggered. When the secondary protection conditions are met, the PLC automatic control unit performs an emergency shutdown, closes the oxygen concentration regulating valve, shuts off the power supply to the preheater, fully opens the nitrogen flow regulating valve, issues an emergency audible and visual alarm to prompt manual intervention, and uses nitrogen to force-purge and cool down until the highest bed temperature drops below 100°C, and then safely shuts down.

10. The method for preventing runaway temperature during the carbonization regeneration of the iron-molybdenum hydrogenation catalyst according to claim 8, characterized in that, In step 5, the preset threshold is 50 ppm, the set duration is 60 min, and in step 6, the set cooling rate is no more than 30 °C / h.

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