Hot high pressure separator and method of improving separation efficiency in a hydroprocessing plant

Abstract

The present application relates to the technical fields of hydrogenation process separation, and discloses a hot high-pressure separator and a method for improving separation efficiency in a hydrogenation process device. The hot high-pressure separator comprises a barrel-shaped shell, a gas phase outlet is formed at the top of the shell, a gas-liquid two-phase inlet is formed at the middle of the shell, and a liquid phase outlet is formed at the bottom of the shell; a plurality of defoaming nets are formed inside the shell between the gas phase outlet and the gas-liquid two-phase inlet, a gas-liquid inlet pre-separator is communicatively arranged on the gas-liquid two-phase inlet, and a plurality of anti-foam accumulation sieve plates are formed inside the shell between the gas-liquid inlet pre-separator and the liquid phase outlet; the gas-liquid inlet pre-separator has a ring pipe structure and is respectively provided with an inlet and an outlet at two sides, the inlet and the outlet are both provided with curved baffles, and a plurality of separation baffles with different angles are arranged inside the ring pipe structure along the tangent direction of the center line. The hot high-pressure separator can effectively slow down or even eliminate the foaming phenomenon, has high working efficiency, large operation flexibility, and improved stability of the operating liquid level.

Description

Technical Field

[0001] This invention relates to the field of separation technology in hydrogenation processes, specifically to a hot high-pressure separator and a method for improving separation efficiency in hydrogenation process units. Background Technology

[0002] As the trend of increasing heavy and inferior crude oil quality becomes more pronounced, national environmental laws and regulations are imposing increasingly stringent requirements on clean fuel products and production processes. Refining enterprises are facing pressure from heavier and inferior feedstocks, lighter and cleaner products, and cleaner and lower-carbon refining processes. Therefore, improving the level of heavy oil conversion and processing, and achieving efficient heavy oil conversion, is key to enhancing the competitiveness of refining enterprises. Residue hydrotreating technology, with its advantages of strong adaptability to feedstocks, high yield of light liquids, and clean and environmentally friendly processing, is increasingly attracting the attention of refining enterprises. Among them, fixed-bed residue hydrotreating has advantages such as mature technology, low operating costs, and high reliability, making it the most effective processing technology for residue oil in refining enterprises.

[0003] The hot high-pressure separator (HHSS), a key separation device in the residue hydrotreating process, serves as the hub connecting the hydrotreating reactor and subsequent separation processes. It performs orderly gas-liquid phase separation of the hydrotreating product oil to obtain a relatively pure product. As the processed oil becomes increasingly heavy, the difficulty of processing the product oil in the HHSS increases. Foaming frequently occurs in the HHSS, manifesting as a failure in HHSS level control. This allows heavy hydrocarbons separated from the HHSS to enter the cold high-pressure separator and cold low-pressure separator, leading to a decrease in the oil-water separation capacity of subsequent separators. HHSS foaming also disrupts the operation of the high- and low-pressure separation systems and the stripping tower system, causing drastic fluctuations in the HHSS level and increasing the risk of high-pressure to low-pressure crosstalk. Therefore, mitigating or eliminating the hazards caused by HHSS foaming is crucial for the stable operation of the hydrotreating unit.

[0004] To mitigate or eliminate the harmful effects of foaming in hot high-temperature fractions, mechanical defoaming and defoaming agents are commonly used to reduce or control foaming. However, adding defoaming agents to feedstock or product oil may affect oil quality and catalyst activity, and the effect of defoaming agents is relatively short-lived, usually requiring continuous replenishment. Most existing gas-liquid separators employ mechanical defoaming, using fluid dynamics to break up foam and improve separation efficiency by modifying the internal structure.

[0005] In addition, CN01276178.8 discloses a high-pressure separator with tangential feeding, in which the fluid undergoes swirling motion on the wall of the separator, and the gas and liquid phases are separated by swirling. However, this scheme has a small centrifugal force and a large amount of gas-liquid entrainment, which cannot effectively separate the gas and liquid phases.

[0006] CN208279571U discloses a separator for collecting and defoaming viscous liquids. It features a cyclone pre-separation component at the inlet, followed by separation via a small cyclone separator. The separated liquid then passes through a multi-layer defoaming plate to eliminate foam carried by the gas-liquid phase. However, its cyclone separator has a small flow rate and is difficult to install, failing to meet the separation requirements for hydrogenated oils from high-viscosity heavy oils.

[0007] CN102380262A and CN102430294B disclose a method of setting multiple micro-swirling structures on the same plane inside a separator to form a micro-swirling group to separate the entrained droplets. However, no corresponding defoaming element is added inside the separator, so it cannot deal with the problem of foaming inside the separator.

[0008] Currently, most hydrogenation process units use symmetrical double-blade inertial separators at the inlet. These separators utilize multiple sets of symmetrical small cyclone blades to cut the jet flow cross-section of the separator inlet pipe into numerous symmetrical, slender, and narrow "inlet pipes," thereby reducing cyclone separation time. This method effectively solves the problem of limited separation space inside the high-pressure separator. However, with this structure spanning the separator, the separated bottom gas can only be discharged upwards from the spaces on both sides of the inlet separator. This can easily carry small droplets falling from the separator wall upwards, causing gas-liquid entrainment and reducing the separator's separation efficiency. Summary of the Invention

[0009] The purpose of this invention is to overcome the foaming phenomenon that occurs on the static surface of the liquid phase at the bottom of the hot high-pressure separator in the existing technology, which is caused by the low separation efficiency and limited operational flexibility of the hot high-pressure separator. This invention provides a hot high-pressure separator that can effectively reduce or even eliminate the foaming phenomenon that occurs on the static surface of the liquid phase at the bottom of the hot high-pressure separator in the low-quality heavy oil hydrotreating product. It has high working efficiency, great operational flexibility, and improves the stability of the operating liquid level.

[0010] To achieve the above objectives, the present invention provides a thermal high-pressure separator, comprising a cylindrical shell, a gas phase outlet at the top, a gas-liquid two-phase inlet in the middle, and a liquid phase outlet at the bottom; multiple layers of demisters are formed inside the shell between the gas phase outlet and the gas-liquid two-phase inlet; a gas-liquid inlet pre-separator is connected to the gas-liquid two-phase inlet; and multiple layers of anti-foaming sieve plates are formed inside the shell between the gas-liquid inlet pre-separator and the liquid phase outlet; wherein...

[0011] The gas-liquid inlet pre-separator has a ring pipe structure with an inlet and an outlet on both sides. Both the inlet and outlet are equipped with curved baffles. Furthermore, the interior of the ring pipe structure has multiple separation baffles at different angles along the tangent of the center line.

[0012] Preferably, the gas-liquid two-phase inlet is located on the side of the shell and above the static liquid level, with the liquid level height being 10%-50% of the height of the hot high-pressure separator cylinder.

[0013] Preferably, the gas-liquid inlet pre-separator is formed by a circular tube with a radius of 10-250 mm, which surrounds the central axis of the shell in 360° with a radius of 0.2D-0.45D. Furthermore, the gas-liquid inlet pre-separator is centrally arranged on the horizontal cross-section at the gas and liquid inlet, and the area ratio of the inner circle to the outer ring of the plane after the gas-liquid inlet pre-separator is placed is 0.5-3.

[0014] Preferably, the separation baffle is located on the outer ring or inner and outer rings of the gas-liquid inlet pre-separator, and one end of the separation baffle is connected to the ring pipe structure, and the other end is attached to the inner wall of the shell. The bending angle of the separation baffle is 60-150° and the extension distance is 10-300mm.

[0015] Preferably, the separation baffles are evenly distributed at 15-45° intervals on the inner and outer rings of the gas-liquid inlet pre-separator.

[0016] Preferably, the multi-layer anti-foaming stacking screen plate includes at least an anti-foaming stacking screen plate located at the low liquid level and an anti-foaming stacking screen plate located at the normal operating liquid level, wherein,

[0017] The anti-foam accumulation screen plate located at the low liquid level is used to eliminate the large amount of foam accumulation that occurs during the initial operation of the thermal high separation unit. The anti-foam accumulation screen plate located at the normal operating liquid level is used to isolate the foam generated during normal operation of the thermal high separation unit from the bottom static liquid phase, and at the same time eliminate the foam carried by the falling liquid phase and the foam generated by the rising gas.

[0018] Preferably, the anti-foam accumulation screen plate has an annular stepped structure, and the multi-level annular stepped structure is connected at an angle of 90°-135°, with the spacing between each step being 10-100mm.

[0019] Preferably, each layer of the annular stepped structure has circular through holes with a radius of 1-25mm evenly spaced every 10°-30°. The through holes on the upper and lower annular stepped structures are staggered. The bottom layer of the anti-foaming sieve plate has circular through holes of 0.5-25mm, and the circular through holes are arranged in a staggered pattern of triangles or squares.

[0020] Preferably, the circular through-hole is provided with one or more defoaming structures selected from cross-shaped, straight, snowflake-shaped, serrated, and needle-shaped structures, and some of the circular through-holes are provided with guide structures, with the defoaming structures extending to the guide structures.

[0021] Preferably, the multi-layer demister is composed of multiple layers of fillers and sieve plates of different specifications, with a gap of 1-30mm between the sieve plates and the fillers.

[0022] Preferably, the packing material is wire mesh corrugated packing, plate corrugated packing, or plate mesh corrugated packing, and the porosity of the packing material is 80%-99%, and the porosity of the packing material in the lower layer is greater than that of the packing material in the upper layer.

[0023] Preferably, a turbulence screen plate is provided between two adjacent layers of packing. The turbulence screen plate has circular through holes of 0.5-10mm. The circular through holes are arranged in a staggered pattern of triangles or squares, with a porosity of 0.5%-50%. Furthermore, the circular through holes in the upper and lower layers are arranged in a staggered pattern.

[0024] The second aspect of the present invention provides a method for improving the separation efficiency in a hydrogenation process unit using the above-mentioned hot high-pressure separator, wherein the operating medium of the hot high-pressure separator is a two-phase mixture of hydrogenation-generated oil and hydrogen, the operating temperature is 260-400℃, and the pressure is 10-17MPa.

[0025] Preferably, the hydrogenated oil is diesel, wax oil, residual oil, or low-quality, easily foaming heavy oil.

[0026] The above technical solution involves installing an annular gas-liquid inlet pre-separator at the gas-liquid two-phase inlet. This pre-separator separates the incoming gas-liquid mixture through a multi-stage swirling flow, throwing liquid droplets carried by the gas phase against the separator wall. The pre-separator initially separates the gas and liquid phases and breaks up air bubbles carried in the feed stream. Most of the separated gas phase is distributed in the upper space of the separator, avoiding contact with liquid droplets flowing out of the separator. The liquid phase falls along the separator wall into the static space at the bottom of the separator under gravity. A multi-layer demister structure is installed at the top of the separator to capture small droplets carried upwards by the gas phase, while also preventing the captured droplets from coking and reducing the demister's collection capacity. The droplets initially separated by the pre-separator fall under gravity onto the lower anti-foaming sieve plate. As the liquid passes through the multi-stage stepped sieve plate, the foam flowing through the sieve plate is elongated and broken by defoaming elements installed in the sieve holes. Guide screen holes are set below the anti-foam accumulation screen plate, and defoaming elements are also installed in the guide screen holes to intercept and break the continuously accumulating foam layer, control the foam accumulation height, and avoid failure of the hot high-level liquid level control system. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a high-pressure thermal separator provided by the present invention;

[0028] Figure 2 This is a schematic diagram of the gas-liquid inlet pre-separator in a thermal high-pressure separator provided by the present invention;

[0029] Figure 3 This is a schematic diagram of the structure of a multi-layer demister in a high-pressure thermal separator provided by the present invention;

[0030] Figure 4This is a schematic diagram of the structure of an anti-foaming screen plate in a high-pressure thermal separator provided by the present invention;

[0031] Figure 5 This is a schematic diagram of various defoaming structures in a hot high-pressure separator provided by the present invention.

[0032] Explanation of reference numerals in the attached figures

[0033] 1-Shell shell 2-Gas-liquid two-phase inlet

[0034] 3-Gas phase outlet 4-Liquid phase outlet

[0035] 5-Gas-liquid inlet pre-separator; 6-Anti-foaming accumulation screen plate

[0036] 7-Defogging screen 51-Curved baffle

[0037] 52-Separation baffle Detailed Implementation

[0038] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0039] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "inner," and "outer" in the terminology represent the orientation of the term in its normal use or are common terms understood by those skilled in the art, and should not be regarded as limitations on the term.

[0040] See Figures 1 to 5 This invention provides a thermal high-pressure separator, which includes a cylindrical shell 1. A gas phase outlet 3 is formed at the top of the shell 1, a gas-liquid two-phase inlet 2 is formed in the middle, and a liquid phase outlet 4 is formed at the bottom. Multiple layers of demister screens 7 are formed inside the shell between the gas phase outlet 3 and the gas-liquid two-phase inlet 2. A gas-liquid inlet pre-separator 5 is connected to the gas-liquid two-phase inlet 2. Multiple layers of anti-foaming sieve plates 6 are formed inside the shell between the gas-liquid inlet pre-separator 5 and the liquid phase outlet 4.

[0041] The gas-liquid inlet pre-separator 5 has a ring pipe structure with an inlet and an outlet on both sides. Both the inlet and outlet are equipped with curved baffles 51. Furthermore, the interior of the ring pipe structure is equipped with multiple separation baffles 52 at different angles along the tangent of the center line.

[0042] In this embodiment, the gas-liquid two-phase inlet 2 is located on the side of the shell 1 and is higher than the static liquid level. The liquid level is 10%-50% of the height of the hot high-pressure separator cylinder.

[0043] In this embodiment, the gas-liquid inlet pre-separator 5 is composed of a circular tube with a radius of 10-250 mm, which surrounds the central axis of the shell by 360° with a radius of 0.2D-0.45D. Furthermore, the gas-liquid inlet pre-separator 5 is centrally arranged on the horizontal cross-section at the gas-liquid two-phase inlet 2, and the ratio of the area of ​​the inner circle to the outer ring of the plane after the gas-liquid inlet pre-separator 5 is placed is 0.5-3.

[0044] In this embodiment, the separation baffle 52 is located on the outer ring or inner and outer rings of the gas-liquid inlet pre-separator 5. One end of the separation baffle 52 is connected to the ring pipe structure, and the other end is attached to the inner wall of the housing 1. The bending angle of the separation baffle 52 is 60-150°, and the extension distance is 10-300mm.

[0045] Furthermore, the separation baffles 52 are evenly distributed at intervals of 15-45° on the inner and outer rings of the gas-liquid inlet pre-separator 5.

[0046] The multi-layer anti-foaming stacking screen plate 6 includes at least an anti-foaming stacking screen plate located at the low liquid level and an anti-foaming stacking screen plate located at the normal operating liquid level, wherein...

[0047] The anti-foam accumulation screen plate located at the low liquid level is used to eliminate the large amount of foam accumulation that occurs during the initial operation of the thermal high separation unit. The anti-foam accumulation screen plate located at the normal operating liquid level is used to isolate the foam generated during normal operation of the thermal high separation unit from the bottom static liquid phase, and at the same time eliminate the foam carried by the falling liquid phase and the foam generated by the rising gas.

[0048] The specific location of the aforementioned anti-foaming accumulation screen plate can be set within a range of 10-200mm above the selected liquid level, or the anti-foaming accumulation screen plate can be set within a range of 10-200mm above the liquid level according to the actual liquid phase height at the bottom of the thermal superfine analyzer.

[0049] The anti-foam stacking screen plate 6 has an overlapping annular stepped structure around the perimeter and in the middle. It can be set with 2-10 levels of anti-foam stacking screen plates connected at a certain angle around the perimeter. The inclination angle can be 90°-135°, and the spacing between each step can be 10-100mm. The number of screen plates or steps is determined according to the properties of the media being separated in the thermal high-temperature separation and the processing volume.

[0050] Each layer of the annular stepped structure has circular through holes with a radius of 1-25mm evenly spaced every 10°-30°. The through holes on the upper and lower annular stepped structures are staggered. The bottom layer of the anti-foaming stacking screen plate 6 has circular through holes of 0.5-25mm, and the circular through holes are arranged in a staggered pattern of triangles or squares.

[0051] The circular through-holes are provided with one or more defoaming structures in the middle, such as cross-shaped, straight, snowflake-shaped, serrated, or needle-shaped. In addition, some circular through-holes are provided with guide structures, and the defoaming structures extend to the guide structures.

[0052] The multi-layer demister 7 is set near the tangent on the cylindrical shell 1. It consists of multiple layers of packing materials and sieve plates of different specifications. A gap of 1-30mm is formed between the sieve plates and the packing materials to ensure that the captured liquid phase accumulates on the sieve plates and avoids secondary entrainment and coking in the packing materials.

[0053] The packing material is wire mesh corrugated packing, plate corrugated packing, or plate mesh corrugated packing. The porosity of the packing material is 80%-99%, and the porosity of the packing material in the lower layer is greater than that of the packing material in the upper layer.

[0054] A turbulence screen plate is installed between two adjacent layers of packing material. The turbulence screen plate has circular through holes of 0.5-10mm, which are arranged in an alternating pattern of triangles or squares. The porosity is 0.5%-50%, and the circular through holes in the upper and lower layers are staggered. This ensures that they do not overlap in the vertical direction, and the opening ratio of the lower layer of the screen plate can be greater or less than that of the upper layer.

[0055] Using the above scheme, the gas and liquid phases enter the pre-separation element through the inlet of the hot high-pressure separator. The separated liquid phase falls along the separator wall to the liquid phase settling zone at the bottom of the separator and leaves the separator through the liquid phase outlet 4. The gas phase flows uniformly upward through the multi-layer defoaming structure and is discharged from the gas phase outlet 3. The multi-layer packing can intercept small droplets entrained during the upward discharge of the gas phase. The droplets on the separator wall fall onto the multi-layer annular stepped anti-foaming sieve plate 6 under the action of gravity. When the liquid passes through the steps, the internal bubbles are elongated, and then the bubbles are broken by the defoaming elements at the sieve holes.

[0056] The gas-liquid inlet pre-separator 5 can be equipped with curved baffles on the outer ring or both the inner and outer rings, depending on the properties of the material to be separated and the operating conditions within the separator. In this embodiment, it is used to enhance the gas-liquid separation process and achieve rapid gas-liquid phase equilibrium within the separator. First, the curved baffles at the inlet of the pre-separator separate the liquid phase from the gas phase entering the separator, changing the direction of movement at the inlet to cause the two phases to move in a ring within the annular tube. Due to the difference in centrifugal force experienced by the gas and liquid phases, the liquid phase passes through the curved baffles and is discharged to the separator wall through the annular opening. As the droplets accumulating on the separator wall gradually grow larger, they enter the liquid phase settling zone at the bottom of the separator. The gas phase is evenly distributed within the separator through openings uniformly arranged on the annular structure. A large space is left in the center of the pre-separator for the gas phase to discharge upwards, thus avoiding gas-liquid entrainment to some extent. An outlet is also provided at the tail end of the pre-separator to prevent residual gas and liquid phases within the separator from affecting the separation process when the throughput is too large.

[0057] Furthermore, the top demister can be a two- or multi-layer demister structure. The porosity of each demister and the number of demister layers are determined based on the properties and throughput of the feedstock oil in the hydrotreating process. In this embodiment, it is used to intercept small droplets carried by the gas phase to the top outlet, reducing the probability of oil droplets entering the subsequent cold high-pressure separator and cold low-pressure separator. First, multiple layers of demisters with different porosities intercept small droplets carried upwards by the gas phase. The small droplets captured by the demisters gradually aggregate into larger droplets and begin to fall downwards, landing on the turbulence sieves set between the demisters. This prevents a large number of droplets from being carried away by the gas phase again during their downward movement. At the same time, the aggregation and prolonged residence of droplets can easily lead to coking. The multi-layer demister structure and the sieves between the demister structures reduce the risk of reduced demister collection performance due to coking.

[0058] The droplets initially separated by the pre-separator fall under gravity onto the lower anti-foaming sieve plate. As the liquid passes through the multi-stage stepped sieve plate, the foam flowing through different steps is elongated and broken up by defoaming elements installed in the sieve holes during its descent. Unbroken foam remains on the surface or inside the sieve plate, preventing it from being carried into the liquid settling area. Guide sieve holes are located below the anti-foaming sieve plate, and defoaming elements are also installed in these holes to intercept and break up the continuously accumulating foam layer below, controlling the foam layer's height and reducing the impact of liquid level fluctuations within the thermal high-temperature zone caused by foaming.

[0059] This invention also provides a method for improving the separation efficiency in a hydrotreating process using the aforementioned hot high-pressure separator, wherein the operating medium of the hot high-pressure separator is a two-phase mixture of hydrotreating product oil and hydrogen, the operating temperature is 260-400℃, and the pressure is 10-17 MPa. This method is particularly suitable for diesel hydrotreating, wax oil hydrotreating, residue oil hydrotreating, or hydrotreating of inferior, easily foaming heavy oil.

[0060] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A hot high-pressure separator, characterized in that, The high-pressure thermal separator includes a cylindrical shell (1), with a gas phase outlet (3) at the top, a gas-liquid two-phase inlet (2) in the middle, and a liquid phase outlet (4) at the bottom. Multiple layers of demister screens (7) are formed inside the shell between the gas phase outlet (3) and the gas-liquid two-phase inlet (2). A gas-liquid inlet pre-separator (5) is connected to the gas-liquid two-phase inlet (2). Multiple layers of anti-foaming sieve plates (6) are formed inside the shell between the gas-liquid inlet pre-separator (5) and the liquid phase outlet (4). The gas-liquid inlet pre-separator (5) is a ring tube structure with an inlet and an outlet on both sides. Both the inlet and the outlet are provided with curved baffles (51). The curved baffles (51) provided at the inlet of the gas-liquid inlet pre-separator (5) separate the liquid phase and the gas phase entering the separator, and change the movement direction at the inlet so that the gas and liquid phases move in a ring in the ring tube. In addition, multiple separation baffles (52) at different angles are provided inside the ring tube structure along the tangent direction of the center line. The gas-liquid inlet pre-separator (5) is composed of a circular tube with a radius of 10-250 mm, which surrounds the central axis of the shell in 360° with a radius of 0.2D-0.45D. The gas-liquid inlet pre-separator (5) is centrally arranged on the horizontal cross section at the gas-liquid two-phase inlet (2). The ratio of the area of ​​the inner circle to the outer ring of the plane after the gas-liquid inlet pre-separator (5) is placed is 0.5-3. The separation baffle (52) is located on the inner and outer rings of the gas-liquid inlet pre-separator (5).

2. The hot high-pressure separator according to claim 1, characterized in that, The gas-liquid two-phase inlet (2) is located on the side of the shell (1) and is higher than the static liquid level. The liquid level is 10%-50% of the height of the hot high pressure separator cylinder.

3. The hot high-pressure separator according to claim 1, characterized in that, The separation baffles (52) are evenly distributed at intervals of 15-45° on the inner and outer rings of the gas-liquid inlet pre-separator (5).

4. The hot high-pressure separator according to claim 1, characterized in that, The multi-layer anti-foaming stacking screen plate (6) includes at least an anti-foaming stacking screen plate located at the low liquid level and an anti-foaming stacking screen plate located at the normal operating liquid level, wherein, The anti-foam accumulation screen plate located at the low liquid level is used to eliminate the large amount of foam accumulation that occurs during the initial operation of the hot high pressure separator. The anti-foam accumulation screen plate located at the normal operating liquid level is used to isolate the foam generated during normal operation of the hot high pressure separator from the bottom static liquid phase, and at the same time eliminate the foam carried by the falling liquid phase and the foam generated by the rising gas.

5. The hot high-pressure separator according to claim 4, characterized in that, The anti-foaming stacking screen plate (6) is an annular stepped structure, and the multiple levels of the annular stepped structure are connected at an angle of 90°-135°, with a spacing of 10-100mm between each step.

6. The hot high-pressure separator according to claim 5, characterized in that, Each layer of the annular stepped structure has circular through holes with a radius of 1-25mm evenly spaced every 10°-30°. The through holes on the upper and lower layers of the annular stepped structure are staggered. The anti-foaming sieve plate (6) at the bottom layer has circular through holes of 0.5-25mm, and the circular through holes are arranged in a staggered pattern of triangles or squares.

7. The hot high-pressure separator according to claim 6, characterized in that, The circular through-hole is provided with one or more defoaming structures in the middle, such as cross-shaped, straight, snowflake-shaped, serrated, or needle-shaped. Furthermore, some of the circular through-holes are provided with guide structures, and the defoaming structures extend to the guide structures.

8. The hot high-pressure separator according to claim 1, characterized in that, The multi-layer demister (7) is composed of multiple layers of fillers and sieve plates of different specifications, with a gap of 1-30mm between the sieve plates and the fillers.

9. The hot high-pressure separator according to claim 8, characterized in that, The packing material is a wire mesh corrugated packing material, a plate corrugated packing material, or a plate mesh corrugated packing material. The porosity of the packing material is 80%-99%, and the porosity of the packing material in the lower layer is greater than that of the packing material in the upper layer.

10. The hot high-pressure separator according to claim 8, characterized in that, A turbulence screen plate is provided between two adjacent layers of packing. The turbulence screen plate has circular through holes of 0.5-10mm. The circular through holes are arranged in a staggered pattern of triangles or squares, with a porosity of 0.5%-50%. Furthermore, the circular through holes in the upper and lower layers are arranged in a staggered pattern.

11. A method for improving separation efficiency in a hydrogenation process unit using a thermal high-pressure separator according to any one of claims 1-10, characterized in that, The operating medium of the hot high-pressure separator is a two-phase mixture of oil and hydrogen produced by hydrogenation, with an operating temperature of 260-400℃ and a pressure of 10-17MPa.

12. The method according to claim 11, characterized in that, The hydrogenated oil is diesel, wax oil, or residual oil.

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