A hot feed fractionation system for a hydrogenation unit

Abstract

This invention discloses a hot feed fractionation system for a hydrogenation unit, relating to the field of distillation technology. It includes a stripping tower, a heat exchanger, a suction pump, and a heater, as well as a fractionation tower. After the diesel feedstock completes the hydrogenation process, it enters the stripping tower. After passing through the stripping tower, the diesel feedstock and other heavy components are discharged into the fractionation tower for fractionation. The diesel and wax oil at the bottom are pumped into the heater and then discharged into the fractionation tower. A first tray is fixedly installed inside the fractionation tower, and multiple riser pipes are fixedly installed on the first tray. Each riser pipe has a support component, and each support component has a movable first bubble cap. Each first bubble cap contains a spiral blade. The rotatable first bubble cap of this invention solves the problem of poor separation effect at key locations. By cooling the spiral blades, heavy components in the rising gas can be separated in advance, reducing the burden on the separation of heavy components.

Description

Technical Field

[0001] This invention relates to the field of distillation technology, and more particularly to a hot feed fractionation system for a hydrogenation unit. Background Technology

[0002] In a hydrotreating unit, feedstock oil (such as catalytic diesel, straight-run diesel, etc.) is mixed with hydrogen and then fed into a hydrorefining reactor via a feed heater. The mixture is then introduced into a stripping tower. Superheated steam is introduced to the bottom of the tower, utilizing the heat provided by the steam and the reduction of the partial pressure between the oil and gas to separate light components (such as hydrogen sulfide, some light hydrocarbons, etc.) from the diesel. These components are discharged from the top of the tower with the steam. The diesel, after preliminary fractionation, enters a fractionation tower. Then, utilizing the differences in boiling points of different substances, the products of the hydrotreating reaction are separated through multiple gas-liquid equilibrium and mass and heat transfer processes. Inside the fractionation tower, the rising gaseous stream and the descending liquid stream make full contact on the trays or packing. This allows volatile light components (such as naphtha) to continuously vaporize from the liquid phase and enter the gas phase, moving towards the top of the tower; while less volatile heavy components (such as wax oil) continuously condense from the gas phase and enter the liquid phase, flowing towards the bottom of the tower. This process separates products with different distillation ranges in different sections of the tower.

[0003] The current process typically involves passing the hydrogenated diesel fuel through a stripping tower, then through heat exchange and heating equipment before entering a fractionation tower. The separated products are then segmented, cooled by various cooling devices, and finally fed into the corresponding tank areas. However, in actual operation, this process has drawbacks such as high product moisture content and high energy consumption.

[0004] In practical use, it was found that the existing bubble cap fractionation column has a problem: when the volume of the bubble cap below the feed inlet is too large, the gas-liquid separation effect is poor, the contact between gas and liquid is insufficient, the contact time is short, and the gas moves a short distance in the liquid. This results in a significant defect in the gas-liquid separation at this point, affecting the overall processing progress of the fractionation column and reducing the separation efficiency of the fractionation column.

[0005] In practical use, it was found that although the above improvements enabled the first bubble cap in areas with large processing volumes to rotate, thereby increasing mass and heat transfer between gas and liquid and alleviating the problem of large gas-liquid processing volumes to some extent, in actual use, since the rising gas contains a certain amount of heavy components, after contacting the liquid inside the first bubble cap, the liquefaction of the heavy components will increase the difficulty of separating the lighter components from the lighter components and increase the content of heavy components. Summary of the Invention

[0006] The purpose of this invention is to provide a hot feed fractionation system for a hydrogenation unit to solve the technical problems mentioned in the background art, namely, the low mass and heat transfer efficiency of light and heavy components in key locations and the easy re-gasification of heavy components.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a hot feed fractionation system for a hydrogenation unit, comprising a fractionation tower, a first tray fixedly disposed within the fractionation tower, a plurality of gas risers fixedly disposed on the first tray, a support member fixedly disposed within each gas riser, a movable first bubble cap disposed on each support member, a spiral blade disposed within each first bubble cap for driving the first bubble cap to rotate, and a flow guide fixedly disposed on the outer circumferential surface of each spiral blade for stabilizing the rotation of the first bubble cap.

[0008] Preferably, each of the spiral blades has a gap between itself and the corresponding guide and the first bubble, for the purpose of allowing the rising gas to escape.

[0009] Preferably, each of the support members is provided with a movable member, each of the movable members is fixedly provided with a conductive member, each of the first blister packs is fixedly provided with a conductive ring, the conductive ring is movable on the support member, each of the conductive members and the outer side of the conductive ring is fixedly provided with a heat-insulating member, and each of the spiral blades is fixedly connected to the corresponding conductive ring, for the purpose of rapidly liquefying the heavy components in the first blister pack.

[0010] Preferably, a first downcomer is provided on one side of the first tray, and a first overflow weir is fixedly provided on the side of the first tray away from the first downcomer.

[0011] Preferably, a gas collecting hood is provided on the side of the riser pipe away from the first bubble, which is used to allow gas to enter the riser pipe and rise faster.

[0012] Preferably, each of the support members has a movable slot, and each movable member is inserted into the corresponding movable slot and can move within the corresponding movable slot.

[0013] Preferably, the fractionation tower is provided with a plurality of second trays, each second tray is provided with a second downcomer, and each second tray is provided with a second overflow weir on the side away from the corresponding second downcomer.

[0014] Preferably, each of the second tower plates is fixedly provided with a plurality of gas riser pipes, each of the gas riser pipes is fixedly provided with a support rod, and each of the support rods is provided with a second bubble cap.

[0015] Preferably, the fractionation tower has a light component outlet and a reflux liquid inlet at the top, a product outlet at the bottom, and a feed inlet on one side.

[0016] Preferably, the fractionation system further includes a stripping tower, a heat exchanger, a suction pump, and a heater. After the diesel feedstock completes the hydrogenation operation, it enters the stripping tower from the top. Superheated steam is introduced from the bottom of the stripping tower. After passing through the stripping tower, the heavy components of the diesel feedstock, such as diesel, pass through the heat exchanger and are discharged into the fractionation tower for fractionation. The diesel and wax oil at the bottom are pumped into the heater and then discharged back into the fractionation tower. The light components are discharged into the reflux tank from the top of the fractionation tower. After condensation, a portion of the reflux liquid enters the top of the fractionation tower as reflux liquid, thus repeating the separation of the feedstock in the fractionation tower.

[0017] The beneficial effects of this invention are:

[0018] 1. By directly heating the material at the bottom of the fractionation tower, fuel gas and steam are saved, and the power consumption of air cooling is reduced. Since diesel and wax oil are directly extracted from the bottom of the fractionation tower and transported directly to the tank area, the water content of the product is reduced, thus improving product quality. After the technical upgrade, the middle section of the fractionation tower is shut down, the diesel stripping tower is shut down, and all wax oil and diesel are mixed at the bottom of the fractionation tower and then sent to the tank area through the diesel external transmission process. Thus, the air cooling of wax oil is shut down, reducing power consumption; the water cooling of wax oil is shut down, reducing circulating water consumption; and the steam injection of the fractionation tower is shut down, reducing steam consumption. The water content in the product is reduced through reboiling circulation, thus improving product quality.

[0019] 2. The support components, spiral blades, and guide components enable the first bubble cap to rotate, thus providing an initial centrifugal force when the bubbles exit from the bottom of the first bubble cap. This allows the bubbles to travel a longer distance in the reflux liquid, prolonging their time in the reflux liquid and increasing the consumption of gas within the bubbles in the reflux liquid. The rotation of the first bubble cap causes the reflux liquid to rotate as well. The vortices generated by adjacent rows of first bubble caps are in opposite directions, causing collisions between the reflux liquid and between the bubbles within it. This increases the contact area between the bubbles and the reflux liquid after the collisions.

[0020] 3. Because the gap between the guide and the first bubble is small, the rising gas can gain a certain acceleration again, so that the bubble moves at a greater speed when it is discharged. The spiral blades can also accelerate the rising gas, making the flow rate of the rising gas faster, which is conducive to making the bubble move better in the liquid and move a greater distance.

[0021] 4. The impact between the reflux liquids can agitate some droplets, allowing the droplets to come into contact with the rising gas, further increasing the contact probability between the reflux liquid and the rising gas. This better consumes the heavy components in the bubbles and the light components in the reflux liquid, causing the light components in the reflux liquid to vaporize and the heavy components in the rising gas to liquefy.

[0022] 5. By enabling the first bubble to rotate, a large amount of viscous raw material oil can be prevented from adhering to the first bubble. This prevents the first bubble from becoming heavier due to the adhesion of raw material oil when it is stationary for a long time, thus reducing the burden on the first bubble when it rotates.

[0023] 6. The moving groove and moving parts enable the first bubble to move up and down. The conductive parts, heat insulation parts and conductive rings enable the lower temperature of the upper layer to be transferred to the spiral blades, thereby reducing the temperature of the spiral blades and causing the heavy components in the rising gas to be liquefied in advance, reducing the probability of the heavy components in the liquid being vaporized again.

[0024] 7. By throwing the liquefied heavy components off the spiral blades, and by using the spiral arrangement of the spiral blades, the movement distance of the heavy components in the rising gas can be increased, and the movement time at lower temperatures can be extended, giving the heavy components sufficient time to liquefy, thereby making the gas-liquid separation more efficient and preventing the heavy components in the rising gas from having a significant impact on the separation effect. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the system of the present invention.

[0026] Figure 2 This is a schematic diagram of the overall structure of the distillation tower in this invention.

[0027] Figure 3 This is a schematic diagram of the full cross-sectional structure of the distillation tower of the present invention.

[0028] Figure 4 This is a schematic diagram showing the distribution of the second bubble cap on the second tray of the present invention.

[0029] Figure 5 This is a cross-sectional view of the structure of the second blister in this invention.

[0030] Figure 6 This is a schematic diagram showing the distribution of the first bubble cap on the first tray in this invention.

[0031] Figure 7 This is a schematic diagram showing the connection relationship of the riser pipe on the first tray of the present invention.

[0032] Figure 8 This is a cross-sectional view of the structure of the first blister pack in this invention.

[0033] Figure 9 This is a schematic diagram showing the connection relationship between the spiral blade and the flow guide in this invention.

[0034] Figure 10 This is a schematic diagram showing the connection relationship between the moving part and the moving slot in this invention.

[0035] The attached diagram is labeled as follows: 1. Stripping tower; 101. Condenser; 2. Heat exchanger; 3. Suction pump; 4. Heater; 5. Fractionating tower; 6. Reflux tank;

[0036] 7. First tray; 701. Gas riser; 702. Support component; 703. First bubble cap; 704. Spiral blade; 705. Flow guide; 706. Conducting component; 707. Insulation component; 708. Conducting ring; 709. First downcomer; 710. First overflow weir; 711. Gas collecting hood; 712. Moving component; 713. Moving trough;

[0037] 8. Second tray; 801. Second downcomer; 802. Second overflow weir; 803. Second gas riser; 804. Support rod; 805. Second bubble cap. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0039] The current process typically involves passing the hydrogenated diesel fuel through stripping tower 1, then through heat exchange and heating equipment before entering fractionation tower 5. The separated products are then segmented, cooled by various cooling devices, and finally fed into the corresponding tank area. However, in actual operation, this process suffers from drawbacks such as high product moisture content and high energy consumption due to the segmented processing method.

[0040] To resolve the above technical issues, please refer to Figures 1 to 10 As shown, the technical solution includes a stripping tower 1, a heat exchanger 2, a suction pump 3, and a heater 4, as well as a fractionation tower 5. After the diesel feedstock completes the hydrogenation operation, it enters the stripping tower 1 from the top. Superheated steam is introduced from the bottom of the stripping tower 1. After passing through the stripping tower 1, the heavy components of the diesel feedstock, such as the diesel feedstock, pass through the heat exchanger 2 and are discharged into the fractionation tower 5 for fractionation. The diesel and wax oil at the bottom enter the heater 4 through the suction pump 3 and are then discharged back into the fractionation tower 5. The light components are discharged into the reflux tank 6 through the top of the fractionation tower 5. After condensation, part of it enters the top of the fractionation tower 5 as reflux liquid, and the feedstock in the fractionation tower 5 is separated repeatedly. The top of the fractionation tower 5 has a light component outlet and a reflux liquid inlet, the bottom of the fractionation tower 5 has a product outlet, and one side of the fractionation tower 5 has a feed inlet.

[0041] In actual production, after the feedstock oil (such as catalytic diesel, straight-run diesel, etc.) is mixed with hydrogen, it enters the hydrorefining reactor through the reaction feed heater. This process is not shown in the figure and is existing technology, so it will not be described in detail here. After the feedstock oil is initially separated and purified, the separated feedstock oil is passed into stripping tower 1. By introducing superheated steam into the bottom of stripping tower 1, the heat provided by the steam and the effect of reducing the partial pressure of oil and gas are used to separate the light components (such as hydrogen sulfide, some light hydrocarbons, etc.) from the diesel oil. The light components are discharged from the top of the tower with the steam. A condenser 101 is set at the top of stripping tower 1. After the light components enter the condenser 101 and are condensed, part of them are returned to the top of stripping tower 1 as reflux liquid to participate in the separation, and the other part is collected and processed.

[0042] After preliminary fractionation, the diesel fuel passes through heat exchanger 2 and enters fractionation tower 5 through the feed inlet. Then, utilizing the boiling point differences of different substances, the products after hydrogenation reaction are separated through multiple gas-liquid equilibrium and mass and heat transfer processes. Inside fractionation tower 5, the rising gaseous stream and the descending liquid stream make full contact on the trays. This fractionation tower 5 is equipped with a temperature monitoring device and control equipment, which are not shown in the figure. When the temperature is too high or too low, the temperature inside fractionation tower 5 is maintained within a suitable range by adjusting the reflux of reflux tank 6 or the heating degree of heater 4. Reflux tank 6 can liquefy higher-temperature gases. This technology is existing technology and will not be described in detail here. The bottom temperature of fractionation tower 5 is controlled to a level that can liquefy diesel fuel and wax oil, so that the volatile light components continuously vaporize from the liquid phase and enter the gas phase, moving towards the top of the tower.

[0043] Non-volatile heavy components, such as wax oil and diesel oil, continuously condense from the gas phase into the liquid phase and flow towards the bottom of the fractionation tower 5. The liquefied diesel oil and wax oil are discharged into the heater 4 through the outlet and suction pump 3 for circulating heating. Only the material at the bottom of the tower is heated, saving energy consumption. The heated material is discharged into the fractionation tower 5 through pipelines to participate in the separation of feed oil again and to provide heat to the fractionation tower 5 to maintain the internal temperature balance. After fractionation, part of the diesel oil and wax oil is discharged to the tank area for storage after suction pump 3. The light components are discharged into the reflux tank 6 through the light component outlet at the top of the fractionation tower 5. After condensation, part of it is used as reflux liquid and enters the fractionation tower 5 through the reflux liquid inlet to participate in the separation of the fractionation tower 5. The excess part is collected and treated. During the process of diesel oil and wax oil being discharged to the tank area, the air cooling and water cooling of wax oil are stopped, reducing energy consumption.

[0044] By directly heating the material at the bottom of fractionation tower 5, fuel gas and steam are saved, and the power consumption of air cooling is reduced. Since diesel and wax oil are directly extracted from the bottom of fractionation tower 5 and transported directly to the tank area, the water content of the product is reduced, thus improving product quality. After the technical upgrade, the middle section extraction of fractionation tower 5 is stopped, diesel stripping tower 1 is stopped, and all wax oil and diesel are mixed at the bottom of fractionation tower 5 and then sent to the tank area through the bottom external process of fractionation tower 5. Thus, the air cooling of wax oil is stopped to reduce power consumption, the water cooling of wax oil is stopped to reduce circulating water consumption, and the steam injection of fractionation tower 5 is stopped to reduce steam consumption. The water content in the product is reduced and the product quality is improved through reboiling circulation. Example 2

[0045] In actual use, it was found that when the existing bubble cap fractionating tower 5 is in use, the bubble cap below the feed inlet has poor gas-liquid separation effect due to the large throughput at this point. The contact between gas and liquid is insufficient, the contact time is short, and the gas moves a short distance in the liquid. This results in a significant defect in gas-liquid separation at this point, affecting the overall processing progress of the fractionating tower 5 and reducing its separation efficiency.

[0046] To resolve the above technical issues, please refer to Figures 1 to 10 As shown, the technical solution includes a fractionation tower 5, a first tray 7 fixedly installed inside the fractionation tower 5, and multiple riser pipes 701 fixedly installed on the first tray 7. Each riser pipe 701 has a fixed support member 702, and each support member 702 has a movable first bubble cap 703. Each first bubble cap 703 has a spiral blade 704 installed inside to drive its rotation. Each spiral blade 704 has a guide member 705 fixedly installed on its outer circumference to ensure stable rotation of the first bubble cap 703. A gap is left between each spiral blade 704, the corresponding guide member 705, and the first bubble cap 703 to allow the rising gas to escape. A first... The first tray 7 has a downcomer 709, and a first overflow weir 710 is fixedly provided on the side of the first tray 7 away from the first downcomer 709. A gas collecting hood 711 is provided on the side of the riser 701 away from the first bubble cap 703, which is used to accelerate the gas into the riser 701. Multiple second trays 8 are fixedly provided in the fractionation column 5. A second downcomer 801 is fixedly provided on each second tray 8. A second overflow weir 802 is fixedly provided on the side of each second tray 8 away from the corresponding second downcomer 801. Multiple second riser pipes 803 are fixedly provided on each second tray 8. A support rod 804 is fixedly provided in each second riser pipe 803. A second bubble cap 805 is provided on each support rod 804.

[0047] When processing is carried out at this location, because the location is close to the heat source, there is sufficient rising gas and the impact force of the rising gas is large. Before the rising gas passes through the riser pipe 701 on the first tower plate 7, the gas enters the gas collecting hood 711 and collects most of the surrounding gas into the riser pipe 701. Since the diameter of the gas collecting hood 711 gradually decreases from the direction away from the first tower plate 7 to the direction closer to the first tower plate 7, the rising gas can be accelerated in the riser pipe 701, resulting in a large initial velocity of the rising gas.

[0048] The feed oil and reflux liquid gradually flow down to the first tray 7 and the second tray 8 on the lower side through the first downcomer 709 and the second downcomer 801. The first overflow weir 710 and the second overflow weir 802 can maintain the liquid at a certain height before it is discharged onto the tray, so that the liquid flows to the first tray 7 and the second tray 8 over a larger range and is more evenly dispersed. The rising gas flows upward through the riser 701, the gas collecting hood 711 and the second riser 803, so that there is a certain contact time between the gas and the liquid, and the mass transfer and heat transfer process is completed.

[0049] After passing through the riser pipe 701, the rising gas enters the guide member 705. The rising gas begins to act on the spiral vane 704. Since the spiral vane 704 is spiral-shaped and has a certain angle, there is a gap between the spiral vane 704 and the guide member 705, allowing the rising gas to pass through the gap and be discharged between the guide member 705 and the first bubble cap 703. Therefore, the rising gas can make the spiral vane 704 rotate on the support member 702. The spiral vane 704 drives the guide member 705 and the first bubble cap 703 to rotate on the support member 702. The rising gas is discharged through the bottom of the first bubble cap 703 and comes into contact with the liquid. Since the gap between the guide member 705 and the first bubble cap 703 is small, the rising gas can gain a certain acceleration again, resulting in a large speed when the bubble is discharged.

[0050] Furthermore, the spiral blade 704 can also accelerate the rising gas to a certain extent, making the rising gas flow rate faster. Since the first bubble cap 703 rotates at this time, the liquid can flow to a certain extent, and at the same time, a centrifugal force is given to the rising gas, making the discharged bubbles uniform in size and enabling the rising gas to move further in the liquid and have a longer contact time, thus better completing the mass and heat transfer between gas and liquid, and better separating the light components from the heavy components, and better liquefying the heavy components and vaporizing the light components.

[0051] When the rising gas enters the second bubble 805 through the second riser pipe 803, the gas is discharged from the bottom of the second bubble 805. Multiple exhaust grooves are provided on the lower end face of the first bubble 703 and the second bubble 805 to facilitate the gas to be dispersed into multiple streams, making the gas more evenly dispersed in the liquid. The discharged gas becomes a liquid bubble and moves in the liquid. After mass and heat transfer, the remaining gas continues to participate as rising gas in the gas-liquid mass and heat transfer reaction of the first tray 7 or the second tray 8 on the next layer.

[0052] Furthermore, the first bubble caps 703 are arranged in rows on the first tray 7, with the spiral blades 704 of adjacent rows having different spiral directions, so that the rotation directions of the first bubble caps 703 of adjacent rows are opposite. Therefore, the movement directions of the reflux liquid and the feed oil are staggered, which better allows the vortices of the reflux liquid to impact each other, disperses the bubbles into smaller bubbles, increases the contact area between the bubbles and the liquid, and is more conducive to heat and mass transfer. Moreover, the impact between the reflux liquids can agitate some droplets, so that the droplets can contact the rising gas, further increasing the contact probability between the reflux liquid and the rising gas, and better consuming the heavy components in the bubbles and the light components in the reflux liquid. In addition, the rotation of the first bubble caps 703 can prevent a large amount of feed oil from adhering to the first bubble caps 703, reducing the impact of feed oil adhesion on the rotation of the first bubble caps 703.

[0053] The support member 702, spiral blade 704, and guide member 705 enable the first bubble cap 703 to rotate. This allows the bubbles to receive an initial centrifugal force as they exit from the bottom of the first bubble cap 703, resulting in a longer distance the bubbles travel in the reflux liquid and extending their travel time. This increases the gas consumption within the reflux liquid. The rotation of the first bubble cap 703 also causes the reflux liquid to rotate. The vortices generated by adjacent rows of first bubble caps 703 are in opposite directions, causing collisions between the reflux liquid and between the bubbles within it. This increases the contact area between the bubbles and the reflux liquid after the collisions. Furthermore, the small gap between the guide member 705 and the first bubble cap 703 allows the rising gas to gain additional acceleration. When the bubbles are expelled, their movement speed is relatively high, and the spiral blades 704 can also accelerate the rising gas to a certain extent, making the flow rate of the rising gas faster. This is beneficial for the bubbles to move better in the liquid and travel a longer distance. The impact between the reflux liquids can agitate some droplets, allowing the droplets to come into contact with the rising gas, further increasing the contact probability between the reflux liquid and the rising gas. This better consumes the heavy components in the bubbles and the light components in the reflux liquid, causing the light components in the reflux liquid to vaporize and the heavy components in the rising gas to liquefy. At the same time, the rotation of the first bubble cap 703 can prevent a large amount of viscous raw material oil from adhering to the first bubble cap 703. This also prevents the first bubble cap 703 from being burdened by the adhesion of the raw material oil when it is stationary for a long time. Example 3

[0054] In actual use, it was found that although the above improvements enabled the first bubble cap 703 in areas with large processing volumes to rotate, thereby increasing mass and heat transfer between gas and liquid and alleviating the problem of large gas-liquid processing volumes to some extent, in actual use, since the rising gas contains a certain amount of heavy components, after contacting the liquid inside the first bubble cap 703, the liquefaction of the heavy components at that location would increase the difficulty of separating the lighter components from the lighter components, increase the content of heavy components, and increase the probability of the heavy components being liquefied again.

[0055] To resolve the above technical issues, please refer to Figures 1 to 10 As shown, the technical solution includes a support member 702, each support member 702 is provided with a movable member 712, each movable member 712 is fixedly provided with a conductive member 706, each first bubble 703 is fixedly provided with a conductive ring 708, the conductive ring 708 can move on the support member 702, each conductive member 706 and the outer side of the conductive ring 708 are fixedly provided with a heat insulation member 707, each spiral blade 704 is fixedly connected to the corresponding conductive ring 708, used to rapidly liquefy the heavy components in the first bubble 703, each support member 702 is provided with a movable groove 713, each movable member 712 is inserted into the corresponding movable groove 713 and can move within the corresponding movable groove 713.

[0056] In practical use, based on the above embodiments one and two, when the rising gas enters the riser pipe 701 through the gas collecting hood 711, the impact force of the rising gas causes the first bubble cap 703 to move upward. The first bubble cap 703 drives the spiral blade 704 and the guide component 705 to move upward. The first bubble cap 703 drives the conduction ring 708 and the heat preservation component 707 to move upward. After the conduction ring 708 moves upward a certain distance, it contacts the conduction component 706 and pushes the conduction component 706 to move upward. The conduction component 706 drives the moving component 712 to move upward. The moving component 712 can slide in the moving groove 713 first. After sliding until the conduction component 706 contacts the upper second tower plate 8, the moving component 712 can rotate in the moving groove 713. This can be solved by using keyways and splines, which are not shown in the figure. This technology is prior art and will not be described in detail here.

[0057] Simultaneously, the spiral blade 704 drives the first bubble cap 703 and the flow guide 705 to rotate, and the first bubble cap 703 drives the conduction ring 708 to rotate. Since the temperature of the second tray 8 located above the first tray 7 is lower, the insulation element 707 is made of heat insulation material, and the conduction ring 708 and the conduction element 706 are made of heat conduction material, so that the second tray 8 exchanges heat with the conduction ring 708 and the conduction element 706, thereby causing the temperature of the conduction ring 708 and the conduction element 706 to drop rapidly.

[0058] Meanwhile, the insulation component 707 can prevent the heat on the conduction ring 708 and the conduction component 706 from exchanging heat with the upper space of the first tray 7 and causing a rapid temperature rise. After the conduction ring 708 lowers its temperature, the temperature of the spiral blade 704 also decreases. As a result, the heavy components liquefy after contacting the spiral blade 704. The released heat is carried out by the rising gas and transfers heat to the liquid, causing the light components to vaporize or be absorbed by the spiral blade 704. This reduces the burden on gas-liquid separation at this point, allowing the heavy components in the rising gas to separate earlier and reducing the content of heavy components discharged from the first bubble cap 703. This makes gas-liquid separation more efficient and reduces the probability of heavy components being vaporized again. The liquefied heavy components are thrown out from the spiral blade 704. Due to the centrifugal force when the spiral blade 704 rotates, the heavy components can be thrown out between the spiral blade 704 and the guide component 705 without falling back into the riser pipe 701, preventing the riser pipe 701 from being blocked.

[0059] Meanwhile, the spiral vane 704, being spirally arranged, allows the rising gas to travel a longer time and a greater distance between the spiral vane 704 and the guide vane 705. This results in better separation of heavy and light components within the spiral vane 704, leading to liquefaction of the heavy components upon contact with the spiral vane 704. This reduces the burden on gas-liquid separation at that point, allowing the heavy components in the rising gas to separate earlier and reducing the content of heavy components discharged from the first bubble cap 703. Consequently, gas-liquid separation becomes more efficient, and the probability of the heavy components being re-vaporized is reduced.

[0060] The first bubble cap 703 can move up and down through the movable groove 713 and the movable component 712. Through the conductive component 706, the heat insulation component 707 and the conductive ring 708, the lower temperature of the upper layer can be transferred to the spiral blade 704, thereby reducing the temperature of the spiral blade 704. This causes the heavy components in the rising gas to be liquefied in advance, reducing the probability of the heavy components in the liquid being vaporized again. The liquefied heavy components are then thrown off the spiral blade 704. At the same time, the spiral arrangement of the spiral blade 704 increases the movement distance of the heavy components in the rising gas and prolongs the movement time at a lower temperature, giving the heavy components sufficient time to liquefy. This makes the gas-liquid separation more efficient and prevents the heavy components in the rising gas from having a significant impact on the separation effect.

[0061] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A hot feed fractionation system for a hydrogenation unit, comprising a fractionation tower (5), characterized in that, It also includes a stripping tower (1), a heat exchanger (2), a suction pump (3) and a heater (4). The fractionation tower (5) is fixedly provided with a first tower plate (7). Multiple riser pipes (701) are provided on the first tower plate (7). Each riser pipe (701) is provided with a support (702). Each support (702) is provided with a movable first bubble cap (703). Each first bubble cap (703) is provided with a spiral blade (704) for driving the first bubble cap (703) to rotate. Each spiral blade (704) is fixedly provided with a guide (705) on its outer circumference for stabilizing the rotation of the first bubble cap (703). Each of the spiral blades (704) has a gap between itself and the corresponding guide (705) and the first bubble (703) to allow the rising air to escape. Each of the support members (702) is provided with a movable member (712), each of the movable members (712) is fixedly provided with a conductive member (706), each of the first blister packs (703) is fixedly provided with a conductive ring (708), the conductive ring (708) is movable on the support member (702), each of the conductive members (706) and the conductive ring (708) is fixedly provided with a heat insulation member (707) on the outside, and each of the spiral blades (704) is fixedly connected to the corresponding conductive ring (708) for rapidly liquefying the heavy components in the first blister pack (703); A first downcomer (709) is provided on one side of the first tray (7), and a first overflow weir (710) is fixed on the side of the first tray (7) away from the first downcomer (709). A gas collecting hood (711) is provided on the side of the riser pipe (701) away from the first bubble cover (703) to allow gas to enter the riser pipe (701) and rise faster. Each of the support members (702) has a movable slot (713) therein, and each of the movable members (712) is inserted into the corresponding movable slot (713) and can move within the corresponding movable slot (713).

2. The hot feed fractionation system for a hydrogenation unit according to claim 1, characterized in that: The fractionation tower (5) is fixedly provided with a plurality of second trays (8), each second tray (8) is fixedly provided with a second downcomer (801), and each second tray (8) is fixedly provided with a second overflow weir (802) on the side away from the corresponding second downcomer (801).

3. The hot feed fractionation system for a hydrogenation unit according to claim 2, characterized in that: Each of the second tower plates (8) is provided with a plurality of gas riser pipes (803), each of the gas riser pipes (803) is fixedly provided with a support rod (804), and each of the support rods (804) is provided with a second bubble cap (805).

4. A hot feed fractionation system for a hydrogenation unit according to claim 3, characterized in that: The fractionation tower (5) has a light component outlet and a reflux liquid inlet at the top, a product outlet at the bottom, and a feed inlet on one side.

5. A hot feed fractionation system for a hydrogenation unit according to claim 4, characterized in that: After the diesel feedstock completes the hydrogenation operation, it enters the stripping tower (1) from the top and the superheated steam enters from the bottom. After passing through the stripping tower (1), the heavy components of the diesel feedstock pass through the heat exchanger (2) and are discharged into the fractionation tower (5) to fractionate the diesel feedstock. The diesel and wax oil at the bottom enter the heater (4) through the suction pump (3) and are then discharged into the fractionation tower (5) again. The light components are discharged into the reflux tank (6) through the top of the fractionation tower (5). After condensation, part of it enters the top of the fractionation tower (5) as reflux liquid, and the feedstock in the fractionation tower (5) is separated again.

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