Fischer-Tropsch synthesis apparatus and methods for treating the oxidative deactivation of iron-based catalysts using it.

Abstract

This invention provides a Fischer-Tropsch synthesis reactor apparatus and a method for oxidatively deactivating an iron-based catalyst using the same. The Fischer-Tropsch synthesis reactor apparatus includes: a Fischer-Tropsch synthesis reactor, heat exchange tubes, a steam drum, and a cyclone separator. The Fischer-Tropsch synthesis reactor is used to perform a first oxidation deactivation of the iron-based catalyst in the Fischer-Tropsch synthesis product system using dynamic cooking to obtain a first product, and then to perform a second oxidation deactivation of the iron-based catalyst in the first product using static cooking to obtain a heavy product and a gas to be discharged. The heat exchange tubes are used to control the temperature inside the reactor. The steam drum is used to heat and melt the wax and iron-based catalyst on the heat exchange tubes. Deionized water is introduced to deactivate the iron-based catalyst on the cyclone separator. Water is introduced through a manhole at the top of the reactor to cool the gas to be discharged, resulting in cooled gas. The top temperature of the Fischer-Tropsch synthesis reactor and the gas state, composition, and CO content of the cooled gas to be discharged are detected to determine whether manual dewaxing is necessary.

Description

Technical Field

[0001] This invention relates to the field of Fischer-Tropsch synthesis technology, and more specifically, to a Fischer-Tropsch synthesis apparatus and a method for treating the oxidative deactivation of iron-based catalysts using the apparatus. Background Technology

[0002] Syngas (CO and H2) undergoes a Fischer-Tropsch synthesis reaction under certain conditions with an iron-based catalyst, producing waxes, heavy hydrocarbons, and light hydrocarbons. This is one of the indirect coal liquefaction technologies. The stable Fischer-Tropsch synthesis iron-based catalyst exists in an oxidized form. It is activated in a catalyst reduction reactor, converting the oxidized iron-based catalyst into iron carbide. Therefore, it is iron carbide that actually undergoes the Fischer-Tropsch synthesis reaction. During the process handover of the Fischer-Tropsch reactor, when the manhole is opened, a large amount of catalyst containing wax and oil adhering to the heat exchange tubes and the top cyclone separator spontaneously combusts upon contact with air. To prevent the fire from spreading and damaging the internal components, manual cleaning inside the reactor is required, making the cleaning extremely difficult. Furthermore, the carbon monoxide released during the combustion process can easily cause personnel poisoning, thus posing a very high risk and resulting in a long process handover time.

[0003] The following problems still exist in the existing technology:

[0004] 1) After the Fischer-Tropsch reactor process finishes its liquid discharge and enters the cooking stage, the partial pressures of the circulating nitrogen and steam entering the reactor are low, which cannot fully oxidize and extinguish the catalyst. Furthermore, the residence time of steam in the Fischer-Tropsch reactor is short, resulting in insufficient contact time with the residual catalyst and failure to destroy its structure.

[0005] 2) During the cooking process, most of the steam in the Fischer-Tropsch reactor remains in the form of steam and cannot destroy the activity of the catalyst. Instead, it evaporates the wax oil that originally wrapped the catalyst, exposing the catalyst completely. After the manhole is opened, the catalyst containing wax oil comes into contact with air and spontaneously combusts.

[0006] 3) The residual catalyst in the Fischer-Tropsch reactor is mainly concentrated on the top cyclone separator and heat exchange tubes, but after the manhole is opened, manual water spraying cannot wash the catalyst above the cyclone separator opposite the manhole.

[0007] 4) The airflow during catalyst passivation was not solidified and the ventilation was too large, causing the residual exposed catalyst to spontaneously combust.

[0008] Therefore, there is an urgent need for a process to solve the problem of spontaneous combustion of Fischer-Tropsch synthesis catalysts after the catalyst is exposed and still has high activity after the Fischer-Tropsch reaction process is handed over, which leads to the opening of the manhole. Summary of the Invention

[0009] The main objective of this invention is to provide a Fischer-Tropsch synthesis apparatus and a method for treating the oxidative deactivation of iron-based catalysts using the apparatus, in order to solve the problem in the prior art where iron-based catalysts in Fischer-Tropsch synthesis are exposed and highly active after the Fischer-Tropsch synthesis reaction process is handed over, leading to spontaneous combustion after the manhole is opened.

[0010] To achieve the above objectives, according to one aspect of the present invention, a Fischer-Tropsch synthesis apparatus is provided, comprising: a Fischer-Tropsch synthesis reactor, a heat exchange tube array, a steam drum, and a cyclone separator. The Fischer-Tropsch synthesis reactor provides a reaction site for a Fischer-Tropsch synthesis product system comprising an iron-based catalyst and a wax. The Fischer-Tropsch synthesis reactor is used to perform a first oxidation deactivation of the iron-based catalyst using dynamic cooking to obtain a first product, and to perform a second oxidation deactivation of the iron-based catalyst in the first product using static cooking to obtain a product comprising a wax and an iron-based catalyst. The reactor contains heavy products of the chemical agent and gases to be discharged; a heat exchange tube array is installed inside the Fischer-Tropsch synthesis reactor, including an upper heat exchange tube array and a lower heat exchange tube array; the heat exchange tube array is used to control the temperature inside the Fischer-Tropsch synthesis reactor; a steam drum is located outside the Fischer-Tropsch synthesis reactor, including an upper steam drum and a lower steam drum. The upper steam drum is connected to the upper heat exchange tube array, and the lower steam drum is connected to the lower heat exchange tube array. The upper steam drum is used to control the temperature of the upper section of the Fischer-Tropsch synthesis reactor, and the lower steam drum is used to control the temperature of the lower section of the Fischer-Tropsch synthesis reactor; the steam drum is used to discharge the upper heat exchange tube array during static cooking. The wax and iron-based catalyst on the tube are heated and melted to obtain heavy products; the temperature of the upper section of the Fischer-Tropsch synthesis reactor is higher than that of the lower section; multiple cyclone separators 4 are arranged horizontally in a ring, and each cyclone separator 4 is located near the top of the Fischer-Tropsch synthesis reactor 1 and inside the reactor 1. The multiple cyclone separators 4 are arranged horizontally in a ring, and there is a certain horizontal distance between each cyclone separator 4 and the inner sidewall of the Fischer-Tropsch synthesis reactor 1; the top sidewall of the Fischer-Tropsch synthesis reactor has multiple demineralized water inlets, each of which is used to introduce demineralized water to flush the iron-based catalyst on the cyclone separators to destroy and deactivate the iron-based catalyst; the Fischer-Tropsch synthesis reactor also includes a top manhole and a bottom manhole. The bottom manhole is used to introduce air into the Fischer-Tropsch synthesis reactor and burn the undeactivated iron-based catalyst, and the top manhole is used to introduce water into the Fischer-Tropsch synthesis reactor to cool the exhaust gas, resulting in cooled exhaust gas; the top temperature of the Fischer-Tropsch synthesis reactor and the gas state, composition, and CO content of the cooled exhaust gas are detected to determine whether artificial wax removal is required.

[0011] Furthermore, the bottom of the Fischer-Tropsch synthesis reactor is also equipped with a nitrogen pipeline and a circulating nitrogen pipeline; the nitrogen pipeline is connected to a first steam cooking line; the bottom of the Fischer-Tropsch synthesis reactor is also equipped with a bottom catalyst feed port, the bottom catalyst feed port is connected to a bottom steam cooking line; the first steam cooking line is used to transport first steam into the Fischer-Tropsch synthesis reactor; the circulating nitrogen pipeline is used to transport first nitrogen into the Fischer-Tropsch synthesis reactor, and the bottom steam cooking line is used to transport second steam into the Fischer-Tropsch synthesis reactor; the first steam and the first nitrogen are mixed and then used with the second steam for dynamic cooking; preferably, the first nitrogen is used to replace the gas in the Fischer-Tropsch synthesis reactor; the first steam and the second steam are used for the first oxidation deactivation of the iron-based catalyst; preferably, the nominal diameter of the first steam cooking line is 80 mm, and / or, the pressure of the first steam is 1.0 MPa, and / or, the pressure of the second steam is 1.0 MPa, and / or, the temperature of the first nitrogen is 110-120°C, and / or, the nominal diameter of the bottom steam cooking line is 40 mm.

[0012] Furthermore, along the axial direction of the Fischer-Tropsch synthesis reactor, an upper catalyst discharge port, a middle catalyst discharge port, and a lower catalyst discharge port are sequentially and spaced apart on the outer wall of the reactor. The upper, middle, and lower catalyst discharge ports are respectively connected to upper, middle, and lower steam cooking lines. These lines are used to supply a third type of steam into the Fischer-Tropsch synthesis reactor for static cooking. And / or, during static cooking, the pressure inside the Fischer-Tropsch synthesis reactor is 0.1–0.15 MPa, and the nominal diameter of each of the upper, middle, and lower steam cooking lines is independently 40 mm.

[0013] Furthermore, the inlet pipes of the upper steam drum and the lower steam drum are respectively connected to the upper steam drum steam pipeline and the lower steam drum steam pipeline; the steam pressure transported by the upper steam drum steam pipeline and the lower steam drum steam pipeline is 5.4 MPa independently; the temperature of the lower section of the Fischer-Tropsch synthesis reactor is 140-150℃, and the temperature of the upper section of the Fischer-Tropsch synthesis reactor is 180-200℃.

[0014] Furthermore, the Fischer-Tropsch synthesis reactor also includes a compressor connected to a circulating nitrogen line, which circulates the first nitrogen gas during the dynamic cooking process; and / or, the nitrogen line supplies a second nitrogen gas to the Fischer-Tropsch synthesis reactor for cooling, with a feed rate of 8000–9000 Nm³. 3 / h; and / or, the Fischer-Tropsch synthesis reactor also includes a pressure vessel connected to the Fischer-Tropsch synthesis reactor, through which heavy products are pressurized into the pressure vessel via a lower catalyst discharge port.

[0015] Furthermore, the combustible gas in the first product is discharged into a flare system connected to the Fischer-Tropsch synthesis reactor.

[0016] Furthermore, the opening angles of the top and bottom manholes are each independently 10–90°; and / or, after flushing with demineralized water, the temperature at the top of the Fischer-Tropsch reactor is tested. When the temperature at the top of the Fischer-Tropsch reactor is ≥70°, the opening angle of the top manhole is opened to 90°, and water is simultaneously introduced into the Fischer-Tropsch reactor through the top manhole for cooling for 20–25 minutes. Then, the introduction of the second nitrogen gas is stopped, and the opening angle of the bottom manhole is opened to 10–15°. The top temperature of the Fischer-Tropsch reactor and the gas state of the exhaust gas after cooling are monitored. The composition of the exhaust gas and its CO content are tested first. The qualified state of the test result is that the top temperature of the Fischer-Tropsch synthesis reactor is ≤40℃, and the exhaust gas after cooling is in the state of water vapor and does not contain flue gas, and the CO content in the exhaust gas after cooling is <25ppm. When the first test result is that the top temperature of the Fischer-Tropsch synthesis reactor is ≥50℃, the exhaust gas after cooling is in the state of water vapor and contains flue gas, and the CO content in the exhaust gas after cooling is ≥25ppm, water is introduced into the Fischer-Tropsch synthesis reactor for 10 minutes every 30 minutes to cool it down, and this is continued for 2 hours until the test result is qualified. The bottom manhole is then opened at an angle increasing by 15-20° each time until it reaches 90°. If the test result is satisfactory, the material enters the Fischer-Tropsch synthesis reactor through both the top and bottom manholes for manual dewaxing. During the process of opening the bottom manhole, before each new angle is opened, it is ensured that the test result is satisfactory; otherwise, water is introduced into the Fischer-Tropsch synthesis reactor for 10 minutes every 30 minutes to cool it down, continuing for 2 hours until the test result is satisfactory. If the first test result shows that the top temperature of the Fischer-Tropsch synthesis reactor is <50°C, and after cooling, the material is ready for discharge... The gas is in a water vapor state and does not contain flue gas. After cooling, when the CO content in the exhaust gas is <25ppm, the opening angle of the bottom manhole is increased by 15-20° each time until the opening angle is 90°. If the test result is qualified, the gas enters the Fischer-Tropsch synthesis reactor through the top and bottom manholes for manual dewaxing. During the process of opening the bottom manhole, before each new angle is opened, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor for 10 minutes every 30 minutes to cool it down, and this continues for 2 hours until the test result is qualified.

[0017] According to another aspect of the present invention, a method for oxidative deactivation of an iron-based catalyst using the above-described Fischer-Tropsch synthesis reactor is provided. The method comprises: performing a first oxidative deactivation on the iron-based catalyst in a Fischer-Tropsch synthesis product system comprising an iron-based catalyst and wax using dynamic cooking within the Fischer-Tropsch synthesis reactor to obtain a first product; performing a second oxidative deactivation on the iron-based catalyst in the first product using static cooking to obtain a heavy product comprising wax and an iron-based catalyst and exhaust gas; and during the static cooking, heating and melting the wax and iron-based catalyst on the upper heat exchange tubes to obtain the heavy product. The temperature of the upper section of the Fischer-Tropsch synthesis reactor is higher than that of the lower section. The iron-based catalyst on the cyclone separator is washed with demineralized water to deactivate it. Air is introduced into the Fischer-Tropsch synthesis reactor through the bottom manhole to burn the undeactivated iron-based catalyst. Water is introduced into the reactor through the top manhole to cool the exhaust gas, resulting in the cooled exhaust gas. The determination of whether artificial dewaxing is necessary is made by detecting the top temperature of the Fischer-Tropsch synthesis reactor, the gas state of the cooled exhaust gas, the composition of the cooled exhaust gas, and the CO content.

[0018] Furthermore, when the concentration of combustible gas in the first product is <5LEL%, static cooking is performed 2-3 hours after the compressor is stopped; and / or, dynamic cooking is performed for 12-16 hours at a temperature of 150-160°C; and / or, static cooking is performed for 14-18 hours at a temperature of 150-180°C; and / or, the rate of demineralized water flow is 10-20 tons / hour.

[0019] Further, after flushing with demineralized water, the temperature at the top of the Fischer-Tropsch reactor is tested. When the temperature at the top of the reactor is ≥70°, the opening angle of the top manhole is opened to 90°, and water is simultaneously introduced into the reactor through the top manhole while a second nitrogen gas is introduced for cooling for 20–25 minutes. Then, the introduction of the second nitrogen gas is stopped, and the opening angle of the bottom manhole is opened to 10–15°. The top temperature of the reactor, the gas state of the vented gas after cooling, the composition of the vented gas after cooling, and the CO content are then measured. The acceptable test results are as follows: the top temperature of the Fischer-Tropsch synthesis reactor is ≤40℃, and the exhaust gas after cooling is in a water vapor state, does not contain flue gas, and the CO content in the exhaust gas after cooling is <25ppm. When the first test result is that the top temperature of the Fischer-Tropsch synthesis reactor is ≥50℃, the exhaust gas after cooling is in a water vapor state, contains flue gas, and the CO content in the exhaust gas after cooling is ≥25ppm, water is introduced into the Fischer-Tropsch synthesis reactor for 10 minutes every 30 minutes for cooling, and this process is continued for 2 hours until the test result is acceptable. Subsequently, the opening angle of the bottom manhole is adjusted according to the following steps. Increase the opening angle by 15-20° until it reaches 90°. If the test result is satisfactory, then manually remove the wax from the Fischer-Tropsch synthesis reactor through the top and bottom manholes. During the process of opening the bottom manhole, ensure the test result is satisfactory before each new angle is opened; otherwise, introduce water into the Fischer-Tropsch synthesis reactor for 10 minutes every 30 minutes to cool it down, continuing for 2 hours until the test result is satisfactory. When the first test result shows the top temperature of the Fischer-Tropsch synthesis reactor is <50°C, and the exhaust gas after cooling is in a water vapor state... Excluding flue gas, when the CO content in the exhaust gas after cooling is <25ppm, the opening angle of the bottom manhole is increased by 15-20° each time until the opening angle is 90°. If the test result is qualified, the gas enters the Fischer-Tropsch synthesis reactor through the top and bottom manholes for manual dewaxing. During the process of opening the bottom manhole, before each new angle is opened, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor for 10 minutes every 30 minutes to cool it down, and this continues for 2 hours until the test result is qualified.

[0020] Applying the technical solution of this invention, this application provides a Fischer-Tropsch synthesis reactor apparatus for scenarios involving the oxidative deactivation of iron-based catalysts in Fischer-Tropsch synthesis reactions. By adding static cooking to the dynamic cooking process within the Fischer-Tropsch reactor, the iron-based catalyst and wax adhering to the upper heat exchange tubes can fall back to the bottom of the reactor under gravity and be expelled, thereby reducing the amount of manual wax removal. Furthermore, static cooking causes a higher degree of damage to the iron-based catalyst. Washing the iron-based catalyst on the cyclone separator within the Fischer-Tropsch reactor with demineralized water also cools the reactor. This allows the demineralized water to vaporize and form a mist during its descent, contacting the iron-based catalyst remaining at the top of the cyclone separator and further deactivating it to a greater degree. Introducing air through the bottom manhole allows even undeactivated iron-based catalyst to burn at lower temperatures, thus preventing spontaneous combustion and potential injury during manual wax removal. After cooling the Fischer-Tropsch synthesis reactor through the top manhole and introducing air through the bottom manhole, the temperature at the top of the reactor and the gas state, composition, and CO content of the cooled exhaust gas discharged from the top manhole can be accurately determined to determine whether manual dewaxing is possible. The Fischer-Tropsch synthesis reactor of this invention can achieve multiple disruptions to the structure of the remaining, undeactivated iron-based catalyst, significantly reducing the risk of injury or death to personnel performing manual dewaxing during emergency repairs. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0022] Figure 1 A schematic diagram of the Fischer-Tropsch synthesis apparatus of this application is shown.

[0023] The above figures include the following reference numerals:

[0024] 1. Fischer-Tropsch synthesis reactor; 2. Heat exchange tubes; 3. Steam drum; 4. Cyclone separator; 5. Pressure tank; 21. Upper heat exchange tubes; 22. Lower heat exchange tubes; 31. Upper steam drum; 32. Lower steam drum; A-1. First steam cooking line; A-2. Bottom steam cooking line; A-3. Upper steam cooking line; A-4. Middle steam cooking line; A-5. Lower steam cooking line; A-6. Upper steam drum steam line; A-7. Lower steam drum steam line; B-1. Circulating nitrogen line; B-2. Nitrogen line; C-1. Bottom catalyst feed port; C-2. Upper catalyst discharge port; C-3. Middle catalyst discharge port; C-4. Lower catalyst discharge port; D-1. First demineralized water valve; D-2. Second demineralized water valve; D-3. Third demineralized water valve. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] As analyzed in the background section of this application, in the prior art, the iron-based catalyst in the Fischer-Tropsch synthesis process is exposed and highly active after the Fischer-Tropsch synthesis reaction process is handed over, which leads to spontaneous combustion after the manhole is opened. In order to solve the above problems, this application provides a Fischer-Tropsch synthesis reaction apparatus and a method for treating the oxidative deactivation of the iron-based catalyst using the apparatus.

[0027] In a typical embodiment of this application, a Fischer-Tropsch synthesis apparatus is provided, such as... Figure 1As shown, the Fischer-Tropsch synthesis reactor includes: a Fischer-Tropsch synthesis reactor 1, a heat exchange tube array 2, a steam drum 3, and a cyclone separator 4. The Fischer-Tropsch synthesis reactor 1 provides a reaction site for a Fischer-Tropsch synthesis product system containing an iron-based catalyst and wax. The Fischer-Tropsch synthesis reactor 1 is used to perform a first oxidation deactivation of the iron-based catalyst using dynamic cooking to obtain a first product, and to perform a second oxidation deactivation of the iron-based catalyst in the first product using static cooking to obtain a heavy product including wax and the iron-based catalyst, and a gas to be discharged. The Fischer-Tropsch synthesis reactor 1 is equipped with a heat exchange tube array. 2. The heat exchange tube 2 includes an upper heat exchange tube 21 and a lower heat exchange tube 22; the heat exchange tube 2 is used to control the temperature inside the Fischer-Tropsch synthesis reactor 1; the steam drum 3 is located outside the Fischer-Tropsch synthesis reactor 1, and the steam drum 3 includes an upper steam drum 31 and a lower steam drum 32. The upper steam drum 31 is connected to the upper heat exchange tube 21, and the lower steam drum 32 is connected to the lower heat exchange tube 22. The upper steam drum 31 is used to control the temperature of the upper section of the Fischer-Tropsch synthesis reactor 1, and the lower steam drum 32 is used to control the temperature of the lower section of the Fischer-Tropsch synthesis reactor 1; the steam drum 3 is used to heat the upper heat exchange tube 21 during static cooking. The wax and iron-based catalyst on 21 are heated and melted to obtain heavy products; the temperature of the upper section of Fischer-Tropsch synthesis reactor 1 is higher than that of the lower section; multiple cyclone separators 4 are arranged horizontally in a ring, and each cyclone separator 4 is horizontally distanced from the inner wall of Fischer-Tropsch synthesis reactor 1; the top sidewall of Fischer-Tropsch synthesis reactor 1 has multiple demineralized water inlets, each demineralized water inlet is used to introduce demineralized water. The iron-based catalyst on the cyclone separator 4 is flushed to deactivate it. The Fischer-Tropsch synthesis reactor 1 also includes a top manhole and a bottom manhole. The bottom manhole is used to introduce air into the Fischer-Tropsch synthesis reactor 1 and burn the undeactivated iron-based catalyst. The top manhole is used to introduce water into the Fischer-Tropsch synthesis reactor 1 to cool the exhaust gas and obtain the cooled exhaust gas. The top temperature of the Fischer-Tropsch synthesis reactor 1 and the gas state, composition and CO content of the cooled exhaust gas are detected to determine whether artificial dewaxing is required.

[0028] This application provides a Fischer-Tropsch synthesis reactor apparatus for scenarios involving the oxidative deactivation of iron-based catalysts in Fischer-Tropsch synthesis reactions. By adding static cooking to the dynamic cooking process within the Fischer-Tropsch reactor 1, the iron-based catalyst and wax adhering to the upper heat exchange tubes 21 of the reactor 1 can fall back to the bottom of the reactor 1 under gravity and be expelled, thereby reducing the amount of wax removed manually. Furthermore, static cooking causes a higher degree of damage to the iron-based catalyst. Washing the iron-based catalyst on the cyclone separator 4 within the Fischer-Tropsch reactor 1 with demineralized water not only removes the adhering iron-based catalyst but also cools the reactor 1. This causes the demineralized water to vaporize during its descent, forming a water mist that contacts the iron-based catalyst at the top of the cyclone separator 4, further deactivating the remaining catalyst with a higher degree of damage. Air is introduced through the bottom manhole, allowing even undeactivated iron-based catalyst to burn at a lower temperature, thus preventing spontaneous combustion and potential injury during manual wax removal. After cooling the Fischer-Tropsch synthesis reactor 1 through the top manhole and introducing air through the bottom manhole, the temperature at the top of the reactor 1, the gas state, composition, and CO content of the cooled exhaust gas discharged from the top manhole can be accurately determined to determine whether manual dewaxing is necessary. The Fischer-Tropsch synthesis reactor of this invention can achieve multiple disruptions to the structure of the remaining, undeactivated iron-based catalyst, significantly reducing the risk of injury or death to personnel performing manual dewaxing during emergency repairs.

[0029] In one embodiment of this application, a nitrogen pipeline and a circulating nitrogen pipeline are further provided at the bottom of the Fischer-Tropsch synthesis reactor 1; a first steam cooking line is connected to the nitrogen pipeline; a bottom catalyst feed port is also provided at the bottom of the Fischer-Tropsch synthesis reactor 1, and a bottom steam cooking line is connected to the bottom catalyst feed port; the first steam cooking line is used to transport first steam into the Fischer-Tropsch synthesis reactor 1; the circulating nitrogen pipeline is used to transport first nitrogen into the Fischer-Tropsch synthesis reactor 1, and the bottom steam cooking line is used to transport second steam into the Fischer-Tropsch synthesis reactor 1. The first steam and the first nitrogen are mixed and then combined with the second steam for dynamic cooking; preferably, the first nitrogen is used to replace the gas in the Fischer-Tropsch synthesis reactor 1; the first steam and the second steam are used to perform the first oxidation deactivation on the iron-based catalyst; preferably, the nominal diameter of the first steam cooking line is 80 mm, and / or, the pressure of the first steam is 1.0 MPa, and / or, the pressure of the second steam is 1.0 MPa, and / or, the temperature of the first nitrogen is 110-120°C, and / or, the nominal diameter of the bottom steam cooking line is 40 mm.

[0030] Adding a first steam cooking line of the aforementioned specifications helps to increase the steam volume by more than 30%, thereby helping to improve the partial pressure of the steam. At the same time, it is more reasonable to set the first steam cooking line at the bottom of the Fischer-Tropsch synthesis reactor 1 to introduce the first steam. The first steam and the first nitrogen are mixed before the distributor. After being distributed by the distributor, the mixed gas is more uniform, thereby further increasing the content of free water and further enhancing the destructive effect on the iron-based catalyst.

[0031] In one embodiment of this application, along the axial direction of the Fischer-Tropsch synthesis reactor 1, an upper catalyst discharge port, a middle catalyst discharge port, and a lower catalyst discharge port are sequentially and spaced apart on the outer wall of the Fischer-Tropsch synthesis reactor 1. The upper catalyst discharge port, the middle catalyst discharge port, and the lower catalyst discharge port are respectively connected to an upper steam cooking pipeline, a middle steam cooking pipeline, and a lower steam cooking pipeline. The upper steam cooking pipeline, the middle steam cooking pipeline, the lower steam cooking pipeline, and the bottom steam cooking pipeline are used to transport third steam into the Fischer-Tropsch synthesis reactor 1 for static cooking; and / or, when static cooking is performed, the pressure inside the Fischer-Tropsch synthesis reactor 1 is 0.1 to 0.15 MPa, and the nominal diameter of the upper steam cooking pipeline, the middle steam cooking pipeline, and the lower steam cooking pipeline is 40 mm each independently.

[0032] Preferably, the content of the third steam during the static cooking process is controlled by adjusting the upper steam cooking pipeline, the middle steam cooking pipeline, the lower steam cooking pipeline and the bottom steam cooking line, and the pressure in the Fischer-Tropsch synthesis reactor 1 is controlled within the above range. This helps to quickly deactivate the exposed and still active iron-based catalyst and melt the iron-based catalyst containing wax oil attached to the upper heat exchange tube 21 and let it fall back to the bottom of the Fischer-Tropsch synthesis reactor 1.

[0033] In one embodiment of this application, the inlet pipes of the upper steam drum 31 and the lower steam drum 32 are respectively connected to the upper steam drum steam pipeline and the lower steam drum steam pipeline; the steam pressure transported by the upper steam drum steam pipeline and the lower steam drum steam pipeline is 5.4 MPa; the temperature of the lower section of the Fischer-Tropsch synthesis reactor 1 is 140-150°C, and the temperature of the upper section of the Fischer-Tropsch synthesis reactor 1 is 180-200°C.

[0034] Preferred control of the steam pressure supplied by the upper and lower steam drums into the upper steam drum 31 and lower steam drum 32, respectively, as well as the temperature of the upper and lower sections of the Fischer-Tropsch synthesis reactor 1, within the aforementioned ranges, helps to allow the iron-based catalyst and wax adhering to the upper heat exchange tubes 21 in the Fischer-Tropsch synthesis reactor 1 to fall back to the bottom of the reactor 1 under gravity and be expelled, thereby reducing the amount of manual wax removal and further improving the degree of damage to the iron-based catalyst.

[0035] In one embodiment of this application, the Fischer-Tropsch synthesis reactor further includes a compressor connected to a circulating nitrogen line, the compressor being used to circulate the first nitrogen gas during the dynamic cooking process; and / or, the nitrogen line being used to supply a second nitrogen gas to the Fischer-Tropsch synthesis reactor 1 for cooling, the feed rate of the second nitrogen gas being 8000–9000 Nm³. 3 / h; and / or, the Fischer-Tropsch synthesis reactor also includes a pressure vessel into which heavy products are pumped through a lower catalyst discharge port.

[0036] Preferably, the compressor described above circulates the first nitrogen gas, which helps to fully replace the gas in the Fischer-Tropsch synthesis reactor 1 during the dynamic cooking process. Preferably, the medium-pressure second nitrogen gas, as described above, is introduced into the bottom of the Fischer-Tropsch synthesis reactor 1 at a controlled feed rate, which helps to further improve the cooling effect.

[0037] In one embodiment of this application, the Fischer-Tropsch synthesis apparatus further includes a pressure tank connected to the Fischer-Tropsch synthesis reactor 1, through which the heavy product is pressurized into the pressure tank via the lower catalyst discharge port.

[0038] By pressing the heavy product into the pressure tank, the amount of manual dewaxing can be further reduced. Before pressing the heavy product into the pressure tank, the pressure tank is a waste catalyst recovery tank equipped with a stirring device. The tank body is equipped with external coil heating, and the temperature is 160-180°C. The stirring device helps to evaporate and dehydrate the heavy product. Evaporation and dehydration help to minimize the occurrence of sudden boiling during the recovery of wax-containing waste iron-based catalysts.

[0039] In one embodiment of this application, the combustible gas in the first product is discharged into a flare system connected to the Fischer-Tropsch synthesis reactor 1.

[0040] Preferably, the combustible gas in the first product is discharged into a flare system connected to the Fischer-Tropsch synthesis reactor 1. This helps to reduce the concentration of combustible gas in the gas to be discharged, thereby minimizing the risk of explosion and improving safety.

[0041] In one embodiment of this application, the opening angles of the top manhole and the bottom manhole are each independently 10–90°; and / or, after flushing with demineralized water, the temperature of the top of the Fischer-Tropsch synthesis reactor 1 is tested. When the temperature of the top of the Fischer-Tropsch synthesis reactor 1 is ≥70°, the opening angle of the top manhole is opened to 90°, and water is simultaneously introduced into the Fischer-Tropsch synthesis reactor 1 through the top manhole for cooling for 20–25 minutes. Then, the introduction of the second nitrogen gas is stopped, and the opening angle of the bottom manhole is opened to 10–15°. The top temperature of the Fischer-Tropsch synthesis reactor 1 and the gas to be vented after cooling are monitored. The composition of the exhaust gas after cooling and its CO content are first tested. The acceptable test results are: the top temperature of Fischer-Tropsch reactor 1 is ≤40℃, the exhaust gas after cooling is in a water vapor state and does not contain flue gas, and the CO content in the exhaust gas after cooling is <25ppm. When the first test result is: the top temperature of Fischer-Tropsch reactor 1 is ≥50℃, the exhaust gas after cooling is in a water vapor state and contains flue gas, and the CO content in the exhaust gas after cooling is ≥25ppm, water is introduced into Fischer-Tropsch reactor 1 for 10 minutes every 30 minutes for cooling, and this process continues for 2 hours until the test results are satisfactory. If the condition is acceptable, the bottom manhole opening angle is increased by 15-20° each time until it reaches 90°. If the test result is acceptable, the material enters the Fischer-Tropsch synthesis reactor 1 through the top and bottom manholes for manual dewaxing. During the process of opening the bottom manhole, before each new angle is opened, ensure the test result is acceptable; otherwise, every 30 minutes, water is introduced into the Fischer-Tropsch synthesis reactor 1 for 10 minutes to cool it down, continuing for 2 hours until the test result is acceptable. If the first test result shows that the top temperature of the Fischer-Tropsch synthesis reactor 1 is <50°C, and the temperature is decreasing... After the exhaust gas is in a water vapor state and does not contain flue gas, when the CO content in the exhaust gas is <25ppm after cooling, the opening angle of the bottom manhole is increased by 15-20° each time until the opening angle is 90°. If the test result is qualified, it enters the Fischer-Tropsch synthesis reactor 1 through the top manhole and the bottom manhole for manual dewaxing. During the process of opening the bottom manhole, before each new angle is opened, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor 1 for 10 minutes every 30 minutes to cool it down and this process is continued for 2 hours until the test result is qualified.

[0042] Controlling the opening angles of the top and bottom manholes to regulate the amount of water and nitrogen introduced helps to cool the Fischer-Tropsch synthesis reactor 1 and monitor the temperature at the top of the reactor, the gas state of the cooled exhaust gas discharged from the top manhole, the composition of the exhaust gas, and whether the CO content is within acceptable limits. This helps to accurately determine whether manual dewaxing can be performed and effectively remove the wax accumulated inside the Fischer-Tropsch synthesis reactor 1, while ensuring personnel safety. Specifically, when the bottom manhole is opened at 90° for the final inspection, continuous monitoring for 2 hours is required, with checks every 10 or 30 minutes during this period. The CO content must be less than 25 ppm to ensure the safety of the manual dewaxing process.

[0043] In a typical embodiment of this application, a method for oxidative deactivation of an iron-based catalyst using the aforementioned Fischer-Tropsch synthesis reactor is provided. The method includes: performing a first oxidative deactivation on the iron-based catalyst in a Fischer-Tropsch synthesis product system comprising an iron-based catalyst and wax using dynamic cooking within the Fischer-Tropsch synthesis reactor 1, obtaining a first product; performing a second oxidative deactivation on the iron-based catalyst in the first product using static cooking, obtaining a heavy product comprising wax and an iron-based catalyst and exhaust gas; and during the static cooking, heating and melting the wax and iron-based catalyst on the upper heat exchange tube 21 to obtain a heavy product. Products; The temperature of the upper section of Fischer-Tropsch synthesis reactor 1 is higher than that of the lower section of Fischer-Tropsch synthesis reactor 1; the iron-based catalyst on the cyclone separator 4 is washed with demineralized water to destroy and deactivate the iron-based catalyst; air is introduced into Fischer-Tropsch synthesis reactor 1 through the bottom manhole and the undeactivated iron-based catalyst is burned; water is introduced into Fischer-Tropsch synthesis reactor 1 through the top manhole to cool the exhaust gas, and the cooled exhaust gas is obtained; the top temperature of Fischer-Tropsch synthesis reactor 1, the gas state of the cooled exhaust gas, the composition of the cooled exhaust gas, and the CO content are detected to determine whether artificial dewaxing is required.

[0044] This application addresses the oxidative deactivation of iron-based catalysts in Fischer-Tropsch synthesis reactions. By adding static cooking to dynamic cooking, the iron-based catalyst and wax adhering to the upper heat exchange tubes 21 within the Fischer-Tropsch reactor 1 can fall back to the bottom of the reactor 1 under gravity and be expelled, thus reducing the amount of wax removed manually. Furthermore, static cooking causes greater damage to the iron-based catalyst. Washing the iron-based catalyst on the cyclone separator 4 within the Fischer-Tropsch reactor 1 with demineralized water also cools the reactor 1, causing the demineralized water to vaporize and further deactivate the iron-based catalyst, resulting in even greater damage. Introducing air through the bottom manhole allows even undeactivated iron-based catalyst to burn at lower temperatures, preventing spontaneous combustion and potential injury during manual wax removal. After cooling the Fischer-Tropsch synthesis reactor 1 through the top manhole and introducing air through the bottom manhole, the temperature at the top of the reactor 1, the gas state, composition, and CO content of the cooled exhaust gas discharged from the top manhole can be accurately determined to determine whether manual dewaxing is necessary. The above-described treatment method of this invention can repeatedly disrupt the structure of the remaining, undeactivated iron-based catalyst, thereby significantly reducing the risk of injury or death to personnel performing manual dewaxing during emergency repairs.

[0045] In one embodiment of this application, when the concentration of combustible gas in the first product is <5LEL%, static cooking is performed after pausing the compressor for 2-3 hours; and / or, dynamic cooking time is 12-16 hours, and / or, dynamic cooking temperature is 150-160°C, and / or, static cooking time is 14-18 hours, and / or, static cooking temperature is 150-180°C; and / or, the rate of demineralized water flow is 10-20 tons / hour.

[0046] Preferably, the concentration of combustible gas in the first product is <5 LEL%, which is considered acceptable. Static cooking is performed after pausing the compressor for the aforementioned time. This facilitates system depressurization after compressor pausing, and all blind flanges connecting the Fischer-Tropsch reactor 1 to the flare are de-blinded. Static cooking after confirming isolation between the Fischer-Tropsch reactor 1 and the flare helps to prevent flare gas backflow as much as possible. Preferably, controlling the temperature and time of dynamic and static cooking within the aforementioned range helps to increase the free water content, thereby further enhancing the destructive effect on the iron-based catalyst. Preferably, controlling the demineralized water flow rate within the aforementioned range helps to thoroughly rinse the iron-based catalyst adhering to the cyclone separator 4, and also cools the Fischer-Tropsch reactor 1, thus allowing the demineralized water to vaporize and further destroy the activity of the iron-based catalyst, and further enhancing the degree of structural damage to the iron-based catalyst. Preferably, the demineralized water flow rate is 10 tons / hour. This is preferably observed by opening the drain outlet at the bottom of the Fischer-Tropsch reactor 1. If the drain outlet is dry, the demineralized water flow rate is adjusted to 15 to 20 tons / hour.

[0047] In one embodiment of this application, after flushing with demineralized water, the temperature at the top of the Fischer-Tropsch synthesis reactor 1 is tested. When the temperature at the top of the reactor 1 is ≥70°, the opening angle of the top manhole is opened to 90°, and water is simultaneously introduced into the reactor 1 through the top manhole while a second nitrogen gas is introduced to cool it down for 20-25 minutes. Then, the introduction of the second nitrogen gas is stopped, and the opening angle of the bottom manhole is opened to 10-15°. The top temperature of the Fischer-Tropsch synthesis reactor 1, the gas state of the vented gas after cooling, the composition of the vented gas after cooling, and the CO content therein are then analyzed. The first test is conducted when the top temperature of the Fischer-Tropsch synthesis reactor 1 is ≤40℃, and the exhaust gas after cooling is in a water vapor state, does not contain flue gas, and the CO content in the exhaust gas after cooling is <25ppm. If the first test result shows that the top temperature of the Fischer-Tropsch synthesis reactor 1 is ≥50℃, the exhaust gas after cooling is in a water vapor state, contains flue gas, and the CO content in the exhaust gas after cooling is ≥25ppm, water is introduced into the Fischer-Tropsch synthesis reactor 1 for 10 minutes every 30 minutes for cooling, continuing for 2 hours until the test result is satisfactory. Then, the opening angle of the bottom manhole is adjusted. The opening angle is increased by 15-20° each time until the opening angle reaches 90°. If the test result is qualified, manual dewaxing is performed by entering the Fischer-Tropsch synthesis reactor 1 through the top and bottom manholes. During the opening of the bottom manhole, before each new angle is opened, it is ensured that the test result is qualified; otherwise, water is introduced into the Fischer-Tropsch synthesis reactor 1 for 10 minutes every 30 minutes to cool it down, continuing for 2 hours until the test result is qualified. When the first test result shows that the top temperature of the Fischer-Tropsch synthesis reactor 1 is <50°C, and the gas to be discharged after cooling is water vapor... When the gas to be discharged is in a state free of flue gas and the CO content in the gas to be discharged after cooling is <25ppm, the opening angle of the bottom manhole is increased by 15-20° each time until the opening angle is 90°. If the test result is qualified, the gas can be manually dewaxed by passing through the top and bottom manholes into the Fischer-Tropsch synthesis reactor 1. During the process of opening the bottom manhole, before each new angle is opened, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor 1 for 10 minutes every 30 minutes to cool it down and this process is continued for 2 hours until the test result is qualified.

[0048] Controlling the opening angles of the top and bottom manholes to regulate the amount of water and nitrogen introduced helps to cool the Fischer-Tropsch synthesis reactor 1 and monitor the temperature at the top of the reactor, the gas state of the cooled exhaust gas discharged from the top manhole, the composition of the exhaust gas, and whether the CO content is within acceptable limits. This helps to accurately determine whether manual dewaxing can be performed and effectively remove the wax accumulated inside the Fischer-Tropsch synthesis reactor 1, while ensuring personnel safety. Specifically, when the bottom manhole is opened at 90° for the final inspection, continuous monitoring for 2 hours is required, with checks every 10 or 30 minutes during this period. The CO content must be less than 25 ppm to ensure the safety of the manual dewaxing process.

[0049] The beneficial effects of this application will be further illustrated below with reference to the embodiments.

[0050] Example 1

[0051] Adopting such Figure 1 The Fischer-Tropsch synthesis apparatus shown oxidizes and deactivates the iron-based catalyst in the Fischer-Tropsch synthesis product system to facilitate artificial dewaxing. Specifically, a first steam cooking line A-1, connected to nitrogen line B-2 at the bottom of Fischer-Tropsch reactor 1, mixes first steam and first nitrogen gas at 110°C, supplied from the compressor via circulating nitrogen line B-1, before entering Fischer-Tropsch reactor 1, to obtain a mixed gas comprising first steam and first nitrogen gas. This mixed gas is then introduced into Fischer-Tropsch reactor 1 through a distributor. Simultaneously, second steam is introduced into Fischer-Tropsch reactor 1 via bottom steam cooking line A-2, connected to bottom catalyst feed port C-1, for dynamic cooking for 16 hours. The first nitrogen gas replaces the gas in Fischer-Tropsch reactor 1, and the first and second steam gases destroy the structure of the iron-based catalyst, yielding the first product. The nominal diameter of the first steam cooking line A-1 is 80 mm, the pressure of the first steam is 1.0 MPa, the pressure of the second steam is 1.0 MPa, and the dynamic cooking temperature is 150°C.

[0052] After dynamic cooking, the combustible gas in the first product is discharged into the flare system connected to the Fischer-Tropsch synthesis reactor 1. Once the concentration of combustible gas in the first product after removal from the Fischer-Tropsch synthesis reactor 1 is <5 LEL%, the compressor is stopped for 2 hours, and the system is depressurized. All blind flanges connected to the flare system are closed, and the demineralized water pipeline connected to the outer wall of the top of the Fischer-Tropsch synthesis reactor 1 is reconnected. Third steam is introduced into the Fischer-Tropsch synthesis reactor 1 through the pipelines connected to the first steam cooking line A-1, the upper catalyst discharge port C-2, the middle catalyst discharge port C-3, and the lower catalyst discharge port C-4, respectively, via the upper steam cooking line A-3, the middle steam cooking line A-4, the lower steam cooking line A-5, and the bottom steam cooking line A-2. Static cooking is then performed for 14 hours, yielding heavy products including wax and iron-based catalyst, and gases to be discharged. Simultaneously, during static cooking, a small amount of cold second nitrogen is introduced through the nitrogen line B-2 to maintain the pressure inside the Fischer-Tropsch synthesis reactor 1 at 0.1 MPa.

[0053] The Fischer-Tropsch synthesis reactor 1 is equipped with a heat exchange tube array 2, which includes an upper heat exchange tube array 21 and a lower heat exchange tube array 22. The steam drum 3 includes an upper steam drum 31 and a lower steam drum 32, which are respectively connected to the upper heat exchange tube array 21 and the lower heat exchange tube array 22. During the static cooking process, the steam flow rate of the 5.4MPa upper steam drum steam pipeline A-6 and the 5.4MPa lower steam drum steam pipeline A-7, connected to the upper steam drum 31 and lower steam drum 32 in steam drum 3, is adjusted to control the temperature of the lower section of the Fischer-Tropsch synthesis reactor 1 at 150℃ and the temperature of the upper section of the Fischer-Tropsch synthesis reactor 1 at 200℃. This melts the wax and iron-based catalyst adhering to the upper heat exchange tubes 21, resulting in a heavy product containing wax and iron-based catalyst. The heavy product falls to the bottom of the Fischer-Tropsch synthesis reactor 1 under gravity. After the static cooking is completed, the wax and deactivated iron-based catalyst are evaporated and dehydrated in a waste catalyst recovery tank equipped with a stirring device at the bottom, and then pressurized to the pressure tank 5 through the lower catalyst discharge port C-4. The static cooking temperature is 150℃.

[0054] Ten cyclone separators are positioned near the top of the Fischer-Tropsch synthesis reactor 1 and within the reactor. Each cyclone separator is arranged in a horizontal ring, with a 1-meter horizontal distance between each separator and the inner wall of the reactor. The pressure in the Fischer-Tropsch synthesis reactor 1 is reduced to atmospheric pressure. The demineralized water lines at the first demineralized water valve D-1, the second demineralized water valve D-2, and the third demineralized water valve D-3 are opened to introduce demineralized water into the reactor, flushing the iron-based catalyst above the cyclone separators 4 and cooling the reactor. Simultaneously, the demineralized water vaporizes upon entering the reactor, and the steam destroys the remaining iron-based catalyst structure, rapidly deactivating it. The demineralized water flow rate is 10 tons per hour.

[0055] After flushing with demineralized water, when the temperature at the top of the Fischer-Tropsch synthesis reactor 1 is 100°C, the opening angle of the top manhole is opened to 90°, and water is introduced into the manhole for cooling for 20 minutes. Simultaneously, 8000 Nm³ of nitrogen is introduced through nitrogen line B-2. 3 The second nitrogen gas is cooled at a rate of / h. Then, the bottom manhole is opened to 15° to obtain the cooled exhaust gas. The top temperature of the Fischer-Tropsch synthesis reactor 1, the gas state of the cooled exhaust gas, the composition of the cooled exhaust gas, and the CO content are then tested. The acceptable test results are: the top temperature of the Fischer-Tropsch synthesis reactor 1 ≤ 40℃; the exhaust gas after cooling is in a water vapor state and does not contain flue gas; and the CO content in the cooled exhaust gas is < 25 ppm. Failure to meet any one of these conditions results in a non-acceptable result.

[0056] The first test result showed that the top temperature of Fischer-Tropsch synthesis reactor 1 was 60°C. After cooling, the exhaust gas was in a water vapor state and contained flue gas. The CO content in the exhaust gas after cooling was 28 ppm. Water was introduced into Fischer-Tropsch synthesis reactor 1 for 10 minutes every 30 minutes to cool it down, and this process was continued for 2 hours until the second test result was qualified.

[0057] The bottom manhole was then opened to 35° for a third test, which was passed. The manhole was then opened to 55° for a fourth test, which was also passed. The manhole was then opened to 75° for a fifth test, which was also passed. Finally, the manhole was opened to 90° for a sixth test, which was also passed. All tests were passed, and the sample entered the Fischer-Tropsch synthesis reactor 1 through both the top and bottom manholes for manual dewaxing. The sixth and final test was conducted continuously for 2 hours, with measurements taken every 10 minutes, and the CO content remained below 25 ppm throughout.

[0058] Example 2

[0059] Adopting such Figure 1The Fischer-Tropsch synthesis apparatus shown oxidizes and deactivates the iron-based catalyst in the Fischer-Tropsch synthesis product system to facilitate artificial dewaxing. Specifically, a first steam cooking line A-1, connected to nitrogen line B-2 at the bottom of Fischer-Tropsch reactor 1, mixes first steam and first nitrogen gas at 120°C, supplied from the compressor via circulating nitrogen line B-1, before entering Fischer-Tropsch reactor 1, to obtain a mixed gas comprising first steam and first nitrogen gas. This mixed gas is then introduced into Fischer-Tropsch reactor 1 through a distributor. Simultaneously, second steam is introduced into Fischer-Tropsch reactor 1 via bottom steam cooking line A-2, connected to bottom catalyst feed port C-1, for dynamic cooking for 12 hours. The first nitrogen gas replaces the gas in Fischer-Tropsch reactor 1, and the first and second steam gases destroy the structure of the iron-based catalyst, yielding the first product. The nominal diameter of the first steam cooking line A-1 is 80 mm, the pressure of the first steam is 1.0 MPa, the pressure of the second steam is 1.0 MPa, and the dynamic cooking temperature is 160°C.

[0060] After dynamic cooking, the combustible gas in the first product is discharged into the flare system connected to the Fischer-Tropsch synthesis reactor 1. Once the concentration of combustible gas in the first product after removal from the Fischer-Tropsch synthesis reactor 1 is <5 LEL%, the compressor is stopped for 3 hours, and the system is depressurized. All blind flanges connected to the flare system are closed, and the demineralized water pipeline connected to the outer wall of the top of the Fischer-Tropsch synthesis reactor 1 is reconnected. Third steam is introduced into the Fischer-Tropsch synthesis reactor 1 through the pipelines connected to the first steam cooking line A-1, the upper catalyst discharge port C-2, the middle catalyst discharge port C-3, and the lower catalyst discharge port C-4, respectively, via the upper steam cooking line A-3, the middle steam cooking line A-4, the lower steam cooking line A-5, and the bottom steam cooking line A-2. Static cooking is then performed for 14 hours, yielding heavy products including wax and iron-based catalyst, and gases to be discharged. Simultaneously, during static cooking, a small amount of cold second nitrogen is introduced through the nitrogen line B-2 to maintain the pressure inside the Fischer-Tropsch synthesis reactor 1 at 0.15 MPa.

[0061] The Fischer-Tropsch synthesis reactor 1 is equipped with a heat exchange tube array 2, which includes an upper heat exchange tube array 21 and a lower heat exchange tube array 22. The steam drum 3 includes an upper steam drum 31 and a lower steam drum 32, which are respectively connected to the upper heat exchange tube array 21 and the lower heat exchange tube array 22. During the static cooking process, the steam flow rate of the 5.4MPa upper steam drum steam pipeline A-6 and the 5.4MPa lower steam drum steam pipeline A-7, connected to the upper steam drum 31 and lower steam drum 32 in steam drum 3, is adjusted to control the temperature of the lower section of the Fischer-Tropsch synthesis reactor 1 at 140℃ and the temperature of the upper section of the Fischer-Tropsch synthesis reactor 1 at 180℃. This melts the wax and iron-based catalyst adhering to the upper heat exchange tubes 21, resulting in a heavy product containing wax and iron-based catalyst. The heavy product falls to the bottom of the Fischer-Tropsch synthesis reactor 1 under gravity. After the static cooking is completed, the wax and deactivated iron-based catalyst are evaporated and dehydrated in a waste catalyst recovery tank equipped with a stirring device at the bottom, and then pressurized to the pressure tank 5 through the lower catalyst discharge port C-4. The static cooking temperature is 180℃.

[0062] Ten cyclone separators are positioned near the top of the Fischer-Tropsch synthesis reactor 1 and within the reactor. Each cyclone separator is arranged in a horizontal ring, with a 1-meter horizontal distance between each separator and the inner wall of the reactor. The pressure in the Fischer-Tropsch synthesis reactor 1 is reduced to atmospheric pressure. The demineralized water lines at the first demineralized water valve D-1, the second demineralized water valve D-2, and the third demineralized water valve D-3 are opened to introduce demineralized water into the reactor, flushing the iron-based catalyst above the cyclone separators 4 and cooling the reactor. Simultaneously, the demineralized water vaporizes upon entering the reactor, and the steam destroys the remaining iron-based catalyst structure, rapidly deactivating it. The initial demineralized water flow rate is 10 tons / hour. After observing the drain at the bottom of the reactor and confirming it is dry, the demineralized water flow rate is adjusted to 20 tons / hour.

[0063] After flushing with demineralized water, when the temperature at the top of the Fischer-Tropsch synthesis reactor 1 is tested to be 80°C, the opening angle of the top manhole is opened to 90°, and water is introduced into the manhole for cooling for 25 minutes. Simultaneously, 8000 Nm³ of nitrogen is introduced through nitrogen line B-2. 3 The second nitrogen gas is cooled at a rate of / h. Then, the bottom manhole is opened to 15° to obtain the cooled exhaust gas. The top temperature of the Fischer-Tropsch synthesis reactor 1, the gas state of the cooled exhaust gas, the composition of the cooled exhaust gas, and the CO content are then tested. The acceptable test results are: the top temperature of the Fischer-Tropsch synthesis reactor 1 ≤ 40℃; the exhaust gas after cooling is in a water vapor state and does not contain flue gas; and the CO content in the cooled exhaust gas is < 25 ppm. Failure to meet any one of these conditions results in a non-acceptable result.

[0064] The first test result showed that the top temperature of Fischer-Tropsch synthesis reactor 1 was 40°C. After cooling, the exhaust gas was in a water vapor state and did not contain flue gas. The CO content in the exhaust gas after cooling was 23 ppm. The bottom manhole was opened to 35°, and the second test result was acceptable. The bottom manhole was opened to 55° for a third test. The third test result showed that the exhaust gas after cooling was in a water vapor state and contained flue gas. The CO content in the exhaust gas after cooling was 27 ppm. Water was introduced into Fischer-Tropsch synthesis reactor 1 for 10 minutes every 30 minutes to cool it down, and this process was continued for 2 hours until the third test result was acceptable.

[0065] The bottom manhole was opened to 75° for a fourth test, which was passed. The bottom manhole was then opened to 90° for a fifth test, which was also passed. With all tests showing a passing result, the material entered the Fischer-Tropsch synthesis reactor 1 through both the top and bottom manholes for manual dewaxing. The fifth and final test was conducted continuously for 2 hours, with measurements taken every 30 minutes, and the CO content remained below 25 ppm throughout.

[0066] Comparative Example 1

[0067] The difference from Example 1 is that the cyclone separator 4 was not cleaned with demineralized water. When the bottom manhole was opened to 90°, the top temperature of the Fischer-Tropsch synthesis reactor 1 was 50°C and the gas to be discharged after cooling was in a water vapor state containing flue gas. The CO content in the gas to be discharged after cooling was 32 ppm.

[0068] Comparative Example 2

[0069] The difference from Example 1 is that the temperature of the upper and lower sections of the Fischer-Tropsch synthesis reactor 1 is the same, both at 220°C. Finally, the top temperature of the Fischer-Tropsch synthesis reactor 1 and the composition of the gas mixture to be tested, the CO content and the gas state are detected. When the bottom manhole is opened to 90°, the top temperature of the Fischer-Tropsch synthesis reactor 1 is detected to be 60°C and the gas to be discharged after cooling is in a water vapor state containing flue gas, and the CO content in the gas to be discharged after cooling is 35ppm.

[0070] Test method:

[0071] The top temperature of the Fischer-Tropsch synthesis reactor was measured using a remote thermometer. The composition of the gas to be discharged after cooling was detected using a portable four-in-one gas detector. The CO content in the gas to be discharged after cooling was detected using a portable carbon monoxide detector. The gas state was determined by observing whether there was water mist in the gas to be discharged after cooling.

[0072] In Comparative Example 1, because the cyclone separator 4 was not cleaned with demineralized water, a large amount of iron-based catalyst remained on the cyclone separator 4, leading to spontaneous combustion after the manhole was opened. In Comparative Example 2, because the temperature of the upper and lower sections of the Fischer-Tropsch synthesis reactor 1 was the same, a large amount of wax and iron-based catalyst remained on the upper heat exchange tubes 21, causing spontaneous combustion after the manhole was opened. No spontaneous combustion occurred in the above embodiments.

[0073] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0074] This application provides a Fischer-Tropsch synthesis reactor apparatus for scenarios involving the oxidative deactivation of iron-based catalysts in Fischer-Tropsch synthesis reactions. By adding static cooking to the dynamic cooking process within the Fischer-Tropsch reactor, the iron-based catalyst and wax adhering to the upper heat exchange tubes can fall back to the bottom of the reactor under gravity and be expelled, thereby reducing the amount of wax removed manually. Furthermore, static cooking causes a higher degree of damage to the iron-based catalyst. Washing the iron-based catalyst on the cyclone separator within the Fischer-Tropsch reactor with demineralized water also cools the reactor. This demineralized water vaporizes during its descent, forming a water mist that contacts the iron-based catalyst remaining at the top of the cyclone separator, further deactivating it to a greater degree. Introducing air through the bottom manhole allows even undeactivated iron-based catalyst to burn at lower temperatures, thus preventing spontaneous combustion and potential injury during manual wax removal. After cooling the Fischer-Tropsch synthesis reactor through the top manhole and introducing air through the bottom manhole, the temperature at the top of the reactor and the gas state, composition, and CO content of the cooled exhaust gas discharged from the top manhole can be accurately determined to determine whether manual dewaxing is possible. The Fischer-Tropsch synthesis reactor of this invention can achieve multiple disruptions to the structure of the remaining, undeactivated iron-based catalyst, significantly reducing the risk of injury or death to personnel performing manual dewaxing during emergency repairs.

[0075] The above are merely embodiments of the present invention and are not intended to limit the invention. Those skilled in the art will recognize that the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A Fischer-Tropsch synthesis apparatus, characterized in that, The Fischer-Tropsch synthesis apparatus includes: The Fischer-Tropsch synthesis reactor (1) provides a reaction site for a Fischer-Tropsch synthesis product system including an iron-based catalyst and wax. The Fischer-Tropsch synthesis reactor (1) is used to perform a first oxidation deactivation of the iron-based catalyst by dynamic cooking to obtain a first product, and to perform a second oxidation deactivation of the iron-based catalyst in the first product by static cooking to obtain a heavy product including wax and the iron-based catalyst and a gas to be discharged. The Fischer-Tropsch synthesis reactor (1) is provided with a heat exchange tube array (2), which includes an upper heat exchange tube array (21) and a lower heat exchange tube array (22); the heat exchange tube array (2) is used to control the temperature inside the Fischer-Tropsch synthesis reactor (1); A steam drum (3) is disposed outside the Fischer-Tropsch synthesis reactor (1). The steam drum (3) includes an upper steam drum (31) and a lower steam drum (32). The upper steam drum (31) is connected to the upper heat exchange tube (21), and the lower steam drum (32) is connected to the lower heat exchange tube (22). The upper steam drum (31) is used to control the temperature of the upper section of the Fischer-Tropsch synthesis reactor (1), and the lower steam drum (32) is used to control the temperature of the lower section of the Fischer-Tropsch synthesis reactor (1). The steam drum (3) is used to heat and melt the wax and the iron-based catalyst on the upper heat exchange tube (21) during the static cooking process to obtain the heavy product. The temperature of the upper section of the Fischer-Tropsch synthesis reactor (1) is higher than the temperature of the lower section of the Fischer-Tropsch synthesis reactor (1). Multiple cyclone separators (4) are arranged in a horizontal ring, with each cyclone separator (4) located near the top of the Fischer-Tropsch synthesis reactor (1) and inside the Fischer-Tropsch synthesis reactor (1). The multiple cyclone separators (4) are arranged in a horizontal ring, and there is a certain horizontal distance between each cyclone separator (4) and the inner wall of the Fischer-Tropsch synthesis reactor (1). The top sidewall of the Fischer-Tropsch synthesis reactor (1) has multiple demineralized water inlets, each of which is used to introduce demineralized water to flush the iron-based catalyst on the cyclone separator (4) to deactivate the iron-based catalyst. The Fischer-Tropsch synthesis reactor (1) further includes a top manhole and a bottom manhole. The bottom manhole is used to introduce air into the Fischer-Tropsch synthesis reactor (1) and burn the undeactivated iron-based catalyst. The top manhole is used to introduce water into the Fischer-Tropsch synthesis reactor (1) to cool the gas to be discharged, thereby obtaining the cooled gas to be discharged. The top temperature of the Fischer-Tropsch synthesis reactor (1) and the gas state of the gas to be vented after cooling, the composition of the gas to be vented after cooling and the CO content therein are detected to determine whether artificial dewaxing is required.

2. The Fischer-Tropsch synthesis apparatus according to claim 1, characterized in that, The bottom of the Fischer-Tropsch synthesis reactor (1) is also provided with a nitrogen pipeline and a circulating nitrogen pipeline; the nitrogen pipeline is connected to a first steam cooking line. The bottom of the Fischer-Tropsch synthesis reactor (1) is also provided with a bottom catalyst feed port, and a bottom steam cooking line is connected to the pipeline of the bottom catalyst feed port. The first steam cooking line is used to deliver the first steam into the Fischer-Tropsch synthesis reactor (1); the circulating nitrogen line is used to deliver the first nitrogen into the Fischer-Tropsch synthesis reactor (1); the bottom steam cooking line is used to deliver the second steam into the Fischer-Tropsch synthesis reactor (1); the first steam and the first nitrogen are mixed and then combined with the second steam for the dynamic cooking process. The first nitrogen gas is used to replace the gas in the Fischer-Tropsch synthesis reactor (1); the first steam and the second steam are used to perform the first oxidation deactivation on the iron-based catalyst; The nominal diameter of the first steam cooking line is 80 mm, and / or the pressure of the first steam is 1.0 MPa, and / or the pressure of the second steam is 1.0 MPa, and / or the temperature of the first nitrogen gas is 110~120℃, and / or the nominal diameter of the bottom steam cooking line is 40 mm.

3. The Fischer-Tropsch synthesis apparatus according to claim 2, characterized in that, Along the axial direction of the Fischer-Tropsch synthesis reactor (1), an upper catalyst discharge port, a middle catalyst discharge port, and a lower catalyst discharge port are sequentially and spaced apart on the outer side wall of the Fischer-Tropsch synthesis reactor (1). The upper catalyst discharge port, the middle catalyst discharge port, and the lower catalyst discharge port are respectively connected to an upper steam cooking pipeline, a middle steam cooking pipeline, and a lower steam cooking pipeline. The upper steam cooking pipeline, the middle steam cooking pipeline, the lower steam cooking pipeline, and the bottom steam cooking pipeline are used to transport third steam into the Fischer-Tropsch synthesis reactor (1) for static cooking. And / or, when the static cooking is performed, the pressure inside the Fischer-Tropsch synthesis reactor (1) is 0.1~0.15 MPa, and the nominal diameter of the upper steam cooking line, the middle steam cooking line and the lower steam cooking line is 40 mm each independently.

4. The Fischer-Tropsch synthesis apparatus according to claim 3, characterized in that, The upper steam drum (31) and the lower steam drum (32) are respectively connected to the upper steam drum steam pipeline and the lower steam drum steam pipeline; the steam pressure transported by the upper steam drum steam pipeline and the lower steam drum steam pipeline is 5.4 MPa; the temperature of the lower section of the Fischer-Tropsch synthesis reactor (1) is 140~150℃, and the temperature of the upper section of the Fischer-Tropsch synthesis reactor (1) is 180~200℃.

5. The Fischer-Tropsch synthesis apparatus according to claim 4, characterized in that, The Fischer-Tropsch synthesis apparatus further includes a compressor connected to the circulating nitrogen pipeline, and the compressor is used to circulate the first nitrogen gas during the dynamic cooking process; And / or, the nitrogen pipeline is used to supply a second nitrogen gas to the Fischer-Tropsch synthesis reactor (1) for cooling, the feed rate of the second nitrogen gas being 8000~9000 Nm³. 3 / h; And / or, the Fischer-Tropsch synthesis apparatus further includes a pressure vessel connected to the Fischer-Tropsch synthesis reactor (1), through which the heavy product is pressurized into the pressure vessel via the lower catalyst discharge port.

6. The Fischer-Tropsch synthesis apparatus according to claim 5, characterized in that, The combustible gas in the first product is discharged into a flare system connected to the Fischer-Tropsch synthesis reactor (1).

7. The Fischer-Tropsch synthesis apparatus according to claim 6, characterized in that, The opening angles of the top manhole and the bottom manhole are each independently 10~90°; And / or, after the demineralized water is introduced for rinsing, the temperature of the top of the Fischer-Tropsch synthesis reactor (1) is tested. When the temperature of the top of the Fischer-Tropsch synthesis reactor (1) is ≥70°, the opening angle of the top manhole is opened to 90°, and the water is introduced into the Fischer-Tropsch synthesis reactor (1) through the top manhole while the second nitrogen gas is introduced to cool down for 20~25 minutes. Then the second nitrogen gas is stopped and the opening angle of the bottom manhole is opened to 10~15°. The top temperature of the Fischer-Tropsch synthesis reactor (1), the gas state of the gas to be vented after cooling, the composition of the gas to be vented after cooling, and the CO content therein are detected for the first time. The qualified state of the test results is that the top temperature of the Fischer-Tropsch synthesis reactor (1) is ≤40℃, and the gas to be discharged after cooling is in the state of water vapor and does not contain flue gas, and the CO content in the gas to be discharged after cooling is <25ppm. When the result of the first test is that the top temperature of the Fischer-Tropsch synthesis reactor (1) is ≥50°C, the gas to be discharged after cooling is in the state of water vapor and contains flue gas, and the CO content in the gas to be discharged after cooling is ≥25ppm, water is introduced into the Fischer-Tropsch synthesis reactor (1) for 10 minutes every 30 minutes to cool it down and this continues for 2 hours until the test result is qualified. Subsequently, the opening angle of the bottom manhole is increased by 15~20° each time until the opening angle is 90°. If the test result is qualified, the artificial wax removal is carried out through the top manhole and the bottom manhole into the Fischer-Tropsch synthesis reactor (1). During the process of opening the bottom manhole, before each time the bottom manhole is opened to a new angle, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor (1) for 10 minutes every 30 minutes to cool it down and this continues for 2 hours until the test result is qualified. When the result of the first test is that the top temperature of the Fischer-Tropsch synthesis reactor (1) is <50°C, and the gas to be discharged after cooling is in a water vapor state and does not contain flue gas, and the CO content in the gas to be discharged after cooling is <25ppm, the opening angle of the bottom manhole is increased by 15~20° each time until the opening angle is 90°. If the test result is qualified, the artificial wax removal is performed by entering the Fischer-Tropsch synthesis reactor (1) through the top manhole and the bottom manhole. During the process of opening the bottom manhole, before each time the bottom manhole is opened to a new angle, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor (1) for 10 minutes every 30 minutes for cooling and this continues for 2 hours until the test result is qualified.

8. A method for treating the oxidative deactivation of an iron-based catalyst using the Fischer-Tropsch synthesis apparatus according to any one of claims 5 to 7, characterized in that, The processing method includes: In the Fischer-Tropsch synthesis reactor (1), the iron-based catalyst in the Fischer-Tropsch synthesis product system, which includes the iron-based catalyst and wax, is subjected to a first oxidation deactivation by dynamic cooking to obtain a first product; the iron-based catalyst in the first product is subjected to a second oxidation deactivation by static cooking to obtain a heavy product including wax and the iron-based catalyst and a gas to be discharged. During the static cooking process, the wax and the iron-based catalyst on the upper heat exchange tube (21) are heated and melted to obtain the heavy product; the temperature of the upper section of the Fischer-Tropsch synthesis reactor (1) is higher than the temperature of the lower section of the Fischer-Tropsch synthesis reactor (1); The iron-based catalyst on the cyclone separator (4) is deactivated by rinsing it with demineralized water. Air is introduced into the Fischer-Tropsch synthesis reactor (1) through the bottom manhole and the undeactivated iron-based catalyst is burned. Water is introduced into the Fischer-Tropsch synthesis reactor (1) through the top manhole to cool the gas to be discharged, and the cooled gas to be discharged is obtained. The need for artificial dewaxing is determined by detecting the top temperature of the Fischer-Tropsch synthesis reactor (1), the gas state of the cooled exhaust gas, the composition of the cooled exhaust gas, and the CO content therein.

9. The processing method according to claim 8, characterized in that, When the concentration of combustible gas in the first product is <5LEL%, the static cooking is performed 2-3 hours after the compressor is stopped; and / or, the dynamic cooking time is 12-16 hours and the dynamic cooking temperature is 150-160°C; and / or, the static cooking time is 14-18 hours and / or, the static cooking temperature is 150-180°C. And / or, the flow rate of the demineralized water is 10-20 tons / hour.

10. The processing method according to claim 9, characterized in that, After the demineralized water is introduced for rinsing, the temperature of the top of the Fischer-Tropsch synthesis reactor (1) is tested. When the temperature of the top of the Fischer-Tropsch synthesis reactor (1) is ≥70°, the opening angle of the top manhole is opened to 90°, and water is introduced into the Fischer-Tropsch synthesis reactor (1) through the top manhole while the second nitrogen gas is introduced to cool it down for 20~25 minutes. Then the second nitrogen gas is stopped and the opening angle of the bottom manhole is opened to 10~15°. The top temperature of the Fischer-Tropsch synthesis reactor (1), the gas state of the gas to be discharged after cooling, the composition of the gas to be discharged after cooling, and the CO content therein are detected for the first time. The qualified state of the test results is that the top temperature of the Fischer-Tropsch synthesis reactor (1) is ≤40℃, and the gas to be discharged after cooling is in the state of water vapor and does not contain flue gas, and the CO content in the gas to be discharged after cooling is <25ppm. When the result of the first test is that the top temperature of the Fischer-Tropsch synthesis reactor (1) is ≥50°C, the gas to be discharged after cooling is in the state of water vapor and contains flue gas, and the CO content in the gas to be discharged after cooling is ≥25ppm, water is introduced into the Fischer-Tropsch synthesis reactor (1) for 10 minutes every 30 minutes to cool it down and this continues for 2 hours until the test result is qualified. Subsequently, the opening angle of the bottom manhole is increased by 15~20° each time until the opening angle is 90°. If the test result is qualified, the artificial wax removal is carried out through the top manhole and the bottom manhole into the Fischer-Tropsch synthesis reactor (1). During the process of opening the bottom manhole, before each time the bottom manhole is opened to a new angle, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor (1) for 10 minutes every 30 minutes to cool it down and this continues for 2 hours until the test result is qualified. When the result of the first test is that the top temperature of the Fischer-Tropsch synthesis reactor (1) is <50°C, and the gas to be discharged after cooling is in a water vapor state and does not contain flue gas, and the CO content in the gas to be discharged after cooling is <25ppm, the opening angle of the bottom manhole is increased by 15~20° each time until the opening angle is 90°. If the test result is qualified, the artificial wax removal is performed by entering the Fischer-Tropsch synthesis reactor (1) through the top manhole and the bottom manhole. During the process of opening the bottom manhole, before each time the bottom manhole is opened to a new angle, it is ensured that the test result is qualified. Otherwise, water is introduced into the Fischer-Tropsch synthesis reactor (1) for 10 minutes every 30 minutes for cooling and this continues for 2 hours until the test result is qualified.

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