Catalytic distillation tower

Abstract

The present invention discloses a catalytic reaction distillation tower, comprising: a catalytic reaction unit, the catalytic reaction unit further comprising: a catalyst bed, which is used to fill a solid catalyst, starting from the second layer, the upper part of the solid catalyst filled in each catalyst bed has an inclined surface; a liquid phase feed subunit, which is arranged above the top first catalyst bed, and the liquid phase feed is guided downward to the first catalyst bed; a gas phase feed subunit, which is arranged between the catalyst bed of the upper layer and the inclined surface of the next layer, and the gas phase feed of each layer enters the catalyst bed upward; a gas phase channel, which is in a relatively isolated state with the gas phase feed subunit, and the gas phase product generated after the gas phase feed and the liquid phase feed react in the catalyst bed directly enters the gas phase channel. The catalytic reaction distillation tower of the present invention also includes a rectification unit, which is arranged on the upper part of the catalytic reaction unit and rectifying the gas phase product generated by the catalytic reaction unit.

Description

Technical Field

[0001] The invention relates to the field of petrochemical industry, and in particular to a catalytic reaction distillation tower. Background Art

[0002] Catalytic distillation has many advantages such as energy saving, high efficiency and good economy. As early as the 1960s, American companies had begun to use the concept of catalytic distillation to solve the problem that it was difficult to separate mixtures containing normal olefins, isoolefins and alkanes by traditional distillation due to similar boiling points. Afterwards, various catalytic distillation equipment came into being based on the characteristics of different reactions. For example: a left-right structured equipment that has both distillation and reaction functions, that is, the left side has a distillation function and is equipped with a distillation tower plate; the right side has a reaction function and is filled with the catalyst required for the reaction, and the left and right chambers are separated by a partition. Another example: a more common catalytic distillation equipment with an upper and lower structure, where the upper and lower structure refers to the relative position of the reaction zone and the distillation zone. US6723886B2 discloses a catalytic distillation equipment with an upper and lower structure for preparing methanol from synthesis gas. There are multiple fixed beds in the equipment. The diameter of the reaction zone can be different at different heights. Whether to fill the catalyst and the thickness of the catalyst can be determined according to the situation in the reaction zone. External heat exchangers, dehydration devices or paraffin separation devices and reflux side lines can be installed at side lines at different positions. The entire catalytic distillation device can also be surrounded by a separate cooling device on the outside.

[0003] In view of the presence of gaseous components in the product, in order to make it easier for the gas to pass through the catalyst bed, the industry has proposed the concept of a gas channel. For example, a gas channel can be embedded in the middle of the catalytic distillation equipment. This gas channel enables the gas phase of the lower bed to directly pass through the upper distillation tower plate layer for mass transfer without passing through the obstruction of the catalyst bed. Multiple gas channels can also be set in the catalytic distillation equipment. The catalytic distillation tower is a cylindrical outer cylinder sealed at the top and bottom, with multiple cylindrical gas channels perpendicular to the cross section. The gas channel is embedded in the reaction zone, and the channel terminal is connected to the open area or medium in the distillation section and the stripping section. The outer cylinder of the reaction zone is filled with a high-density catalyst, and the inner cylinder wall can be opened to allow it to be in close contact with the catalyst.

[0004] In summary, the existing catalytic distillation technology itself improves the reaction efficiency and product separation. In the application of catalytic distillation technology, reactors and their internal components have also formed various forms, but the efficiency of current reactors and internal components needs to be further improved, especially the existing technology cannot effectively solve the problem of timely separation of gas-phase reaction products from the reaction zone. Therefore, there is an urgent need for a distillation tower with a catalytic reaction unit to solve the separation efficiency problem in the prior art. In the case where the gas-phase product can undergo a secondary reaction, efficient separation can still be carried out. At the same time, a gas-phase product with a higher pass rate can be formed in the tower through the distillation unit at the top of the reaction zone, further improving the product efficiency and pass rate.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The object of the present invention is to provide a catalytic reaction distillation tower, thereby overcoming the shortcoming in the prior art that the gas phase reaction products cannot be effectively separated from the reaction zone in a timely manner, especially in the case where the gas phase products can undergo secondary reactions, efficient separation can still be performed.

[0007] Another object of the present invention is to further improve the efficiency and qualified rate of gas phase products by coupling the catalytic reaction unit and the distillation unit in the tower.

[0008] To achieve the above-mentioned purpose, the present invention provides a catalytic reaction distillation tower, comprising: a catalytic reaction unit, the catalytic reaction unit further comprising: a catalyst bed, which is used to fill a solid catalyst, and starting from the second layer, the upper part of the solid catalyst filled in each catalyst bed has an inclined surface; a liquid-phase feed subunit, which is arranged above the top first catalyst bed, and the liquid-phase feed is guided downward to the first catalyst bed; a gas-phase feed subunit, which is arranged between the catalyst bed of the upper layer and the inclined surface of the next layer, and the gas-phase feed of each layer enters the catalyst bed upward; a gas-phase channel, which is in a relatively isolated state from the gas-phase feed subunit, and the gas-phase product generated after the gas-phase feed and the liquid-phase feed react in the catalyst bed directly enters the gas-phase channel. The catalytic reaction distillation tower of the present invention also includes a rectification unit, which is arranged on the upper part of the catalytic reaction unit and rectifying the gas-phase product generated by the catalytic reaction unit.

[0009] Furthermore, in the above technical solution, the gas phase channel can be located outside the catalytic reaction unit and be annular and penetrate all catalyst beds from bottom to top. In addition, the gas phase channel can also be arranged in the middle of the catalytic reaction unit.

[0010] Furthermore, in the above technical solution, the inclined surface as a whole can be designed as an inverted umbrella-shaped partition structure. The end of the inverted umbrella-shaped partition can be provided with an inner downcomer, the bottom of which is spaced a distance from the bottom of the catalyst bed, so that the liquid feed enters the catalyst bed in a radial direction.

[0011] Furthermore, in the above technical solution, the catalyst bed may be provided with: an overflow weir, which is arranged on the side close to the gas phase channel; and a liquid sealing baffle, which is arranged on the upper part of the overflow weir to isolate the gas phase feed from the gas phase product.

[0012] Furthermore, in the above technical solution, the liquid seal baffle may include: a horizontal portion, which is an annular flat plate and is located above the overflow weir; a vertical portion, which is cylindrical and is integrally formed with the horizontal portion, and the lower end of the vertical portion is spaced a distance from the bottom of the catalyst bed.

[0013] Furthermore, in the above technical solution, the liquid-phase feed subunit further includes: a liquid-phase feed pipe, which extends along the radial direction of the catalytic reaction unit; a liquid-phase distribution pipe, which is annular and intersects orthogonally or tangentially with the liquid-phase feed pipe, and the tube wall of the liquid-phase distribution pipe is provided with a plurality of channels for evenly distributing the liquid-phase feed to various positions above the first catalyst bed layer.

[0014] Furthermore, in the above technical solution, the gas-phase feed subunit may further include: a gas-phase feed pipe, which extends along the radial direction of the catalytic reaction unit; a gas-phase distribution pipe, which is annular or has multiple layers of concentric rings, and the gas-phase distribution pipe intersects the gas-phase feed pipe orthogonally or tangentially, and a plurality of holes are provided on the wall of the gas-phase distribution pipe for evenly distributing the gas-phase feed to all directions at the bottom of the catalyst bed.

[0015] Furthermore, in the above technical solution, the gas phase feeding subunit may also include: a gas phase distribution plate, which is located at the bottom of the catalyst bed and is disk-shaped as a whole, and a plurality of holes are evenly and densely distributed on the gas phase distribution plate.

[0016] Furthermore, in the above technical solution, the gas phase distribution pipe can be arranged below the catalyst bed or inside the catalyst bed.

[0017] Furthermore, in the above technical solution, the distillation unit may be provided with an inert packing layer, and the rising gas phase product from the gas phase channel is distilled in the inert packing layer.

[0018] Furthermore, in the above technical solution, a guide unit is provided between the inert filler layer and the first catalyst bed layer, and the guide unit as a whole is an inverted umbrella-shaped partition structure; the partition is a hollow structure at a position corresponding to the gas phase channel on one side close to the distillation tower wall, and an opening is provided on the side close to the middle of the distillation tower for the liquid phase heavy components descending after distillation to enter the catalytic reaction unit.

[0019] Furthermore, in the above technical solution, the catalytic reaction distillation tower can be a multi-layer plate tower structure. The number of catalyst beds in the catalytic reaction distillation tower is two or more layers.

[0020] Furthermore, in the above technical solution, the catalytic reaction distillation tower is suitable for a reaction system in which at least one liquid feed and at least one gas feed undergo a chemical reaction on a solid catalyst, and at least one gas product is produced as a reaction product.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) After the reactants used in the present invention undergo chemical reactions in the catalyst bed, the gaseous products generated will leave the reaction zone in time and undergo distillation, and will not re-enter the catalyst bed of the previous layer, thereby avoiding secondary reactions of the target products and improving the selectivity of the reaction;

[0023] 2) The timely departure of gaseous products from the reaction zone increases the driving force of the reaction and improves the equilibrium conversion rate;

[0024] 3) The inverted first umbrella-shaped baffle can separate the gaseous feed and gaseous product between adjacent beds on the one hand, and play a role in guiding the liquid and gas phases on the other hand;

[0025] 4) The liquid seal baffle can effectively isolate the gas phase feed from the gas phase product;

[0026] 5) The arrangement of multiple layers of concentric annular gas phase distribution pipes can keep the distribution of gas phase feed uniform to the maximum extent;

[0027] 6) The inverted second umbrella-shaped baffle can, on the one hand, guide the gas phase product from the gas phase channel of the reaction zone to the upper inert filler layer through the hollow structure arranged on the annular tower wall; on the other hand, it can guide the liquid phase heavy components generated in the distillation process to the opening at the central end of the baffle through the inclined baffle, so that the liquid phase heavy components can flow back into the reaction zone;

[0028] 7) The setting of the distillation unit at the upper part of the reaction zone can achieve a higher qualified rate of gas phase products in the tower, further improve product efficiency and maximize energy saving goals;

[0029] 8) The catalytic reaction unit of the present invention is applicable to a reaction system in which at least one liquid feed and at least one gas feed undergo a chemical reaction on a solid catalyst, and the reaction products include at least one gas product.

[0030] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, and to make the above and other purposes, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the catalytic reaction distillation tower of the present invention.

[0032] Figure 2 It is a top view of the liquid phase distribution pipe in the catalytic reaction unit of the present invention.

[0033] Figure 3 It is a top view of the gas-phase feed pipe and the gas-phase distribution pipe in the catalytic reaction unit of the present invention (showing the situation where the gas-phase feed pipe and the annular gas-phase distribution pipe are arranged orthogonally).

[0034] Figure 4 It is another top view of the gas-phase feed pipe and the gas-phase distribution pipe in the catalytic reaction unit of the present invention (showing the situation where the gas-phase feed pipe and the annular gas-phase distribution pipe are arranged tangentially and intersectingly).

[0035] Figure 5 It is a top view of the gas phase distribution pipe of the present invention which adopts a concentric double-ring distribution pipe.

[0036] Figure 6 It is a top view of the gas phase distribution plate in the catalytic reaction unit of the present invention.

[0037] Figure 7 It is a top view of the catalyst support plate in the catalytic reaction unit of the present invention.

[0038] Figure 8 It is a top view of the inert filler support plate in the distillation unit of the present invention.

[0039] Fig. 9 It is a top view of the guide unit in the distillation unit of the present invention.

[0040] Description of main reference numerals:

[0041] 1-catalytic reaction distillation tower, 10-solid catalyst, 11-first umbrella-shaped baffle, 12-inner downcomer, 13-gas phase channel, 14-overflow weir, 15-downcomer folding plate, 16-liquid receiving tray, 17-liquid sealing baffle, 18-outer downcomer, 19-catalyst support plate, 191-grid;

[0042] 21-liquid phase feed pipe, 22-liquid phase distribution pipe, 220-liquid phase distribution pipe body, 221-liquid phase channel;

[0043] 31-gas phase feed pipe, 32-gas phase distribution pipe, 320-gas phase distribution pipe body, 321-gas phase channel, 33-gas phase distribution plate, 331-hole;

[0044] 41 - second umbrella-shaped partition, 411 - hollow portion, 42 - liquid phase heavy component collecting port, 43 - filler support plate, 44 - inert filler. DETAILED DESCRIPTION

[0045] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0046] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0047] In this document, for the convenience of description, spatial relative terms such as "below", "below", "down", "above", "above", "upper", etc. may be used to describe the relationship between one element or feature and another element or feature in the accompanying drawings. It should be understood that the spatial relative terms are intended to include different directions of objects in use or operation in addition to the directions drawn in the drawings. For example, if the object in the figure is turned over, the elements described as being "below" or "below" other elements or features will be oriented "above" the elements or features. Therefore, the exemplary term "below" can include both below and above directions. Objects may also have other orientations (rotated 90 degrees or other orientations) and the spatial relative terms used in this document should be interpreted accordingly.

[0048] In this document, the terms "first", "second", etc. are used to distinguish two different elements or parts, and are not used to limit a specific position or relative relationship. In other words, in some embodiments, the terms "first", "second", etc. can also be interchangeable.

[0049] like Figure 1As shown, the catalytic reaction distillation tower 1 of the present invention is an upper and lower structure, wherein a catalytic reaction unit is arranged in the lower part of the tower, and a distillation unit is arranged in the upper part of the tower. The catalytic reaction unit is an internal component of the reaction distillation tower 1, and includes a catalyst bed, a liquid-phase feed subunit, a gas-phase feed subunit, and a gas-phase channel. The catalyst bed is used to fill the solid catalyst 10. Starting from the second layer at the top, the upper part of the solid catalyst 10 filled in each catalyst bed has an inclined surface. The overall shape formed by the inclined surface can be an inverted umbrella shape, which acts as a partition. On the one hand, it can separate the gas-phase feed and the product gas between adjacent beds, and on the other hand, it plays a role in guiding the liquid phase and the gas phase. Preferably, but not restrictively, the inverted umbrella surface can be an arc shape or a folding umbrella shape. The liquid-phase feed subunit is arranged above the top first catalyst bed layer, and the liquid-phase feed is guided downward to the first catalyst bed layer to contact the solid catalyst 10. Specifically, an inner downcomer 12 (i.e. Figure 1 The bottom of the inner downcomer 12 is spaced from the bottom of the catalyst bed by a distance, so that the liquid feed enters the catalyst bed along the radial direction of the reaction distillation tower 1. The gas-phase feed subunit is arranged in each catalyst bed, specifically between the catalyst bed of the upper layer and the inverted first umbrella-shaped partition 11 of the lower layer, and the gas-phase feed of each layer enters the catalyst bed upward. After the gas-liquid phase feed and the solid catalyst 10 are fully reacted in the catalyst bed, the gas-phase product of each layer is guided to the gas-phase channel 13 along the lower part of the inverted first umbrella-shaped partition 11. The gas-phase channel 13 is in a relatively isolated state from the gas-phase feed subunit, that is, the gas-phase product generated after the gas-phase feed and the liquid-phase feed react in the catalyst bed directly enters the gas-phase channel 13. Preferably, but not restrictively, the gas-phase channel is located on the outside of the reaction distillation tower 1, is annular and passes through all catalyst beds from bottom to top.

[0050] Further Figure 1 , 2As shown, the liquid-phase feed subunit further includes a liquid-phase feed pipe 21 and a liquid-phase distribution pipe 22. The liquid-phase feed pipe 21 extends in the radial direction of the catalytic reaction unit, and the liquid-phase distribution pipe 22 is annular. The liquid-phase feed pipe 21 intersects orthogonally or tangentially with the pipe body 220 of the liquid-phase distribution pipe 22. The pipe wall of the liquid-phase distribution pipe 22 is provided with a plurality of channels 221 for evenly distributing the liquid-phase feed to various positions above the first catalyst bed. The openings of the channels 221 can be in various directions on the upper, lower and side surfaces of the pipe body. The liquid-phase feed enters the reaction distillation tower 1 through the liquid-phase feed pipe 21, enters the tower through the annular liquid-phase distribution pipe 22, and is distributed to the first catalyst bed. The annular diameter of the annular liquid-phase distribution pipe 22 is larger than the outer diameter of the inner downcomer 12, and smaller than the inner diameter of the reaction distillation tower 1. The height of the downcomer fold 15 is generally smaller than the height of the catalyst loading in this layer, and the size of the space enclosed by the downcomer fold 15 is determined according to the flow rate of the liquid phase reactant in this layer.

[0051] Further Figure 1 As shown, the height of each catalyst bed in the reaction distillation tower 1 can be the same or different, depending on the different chemical reaction systems. The catalyst bed is fixed with a screen to keep the bed relatively stable, and the bed height is set to 10mm to 1000mm. The catalyst bed is provided with an overflow weir 14 and a liquid seal baffle 17, and the overflow weir 14 is arranged on the side close to the gas phase channel 13. The liquid seal baffle 17 is arranged on the upper part of the overflow weir 14 to isolate the gas phase feed from the gas phase product. Further, the liquid seal baffle 17 includes a horizontal part and a vertical part, the horizontal part is an annular flat plate and is located above the overflow weir 14; the vertical part is cylindrical, and the vertical part is integrally formed with the horizontal part, and other seamless connection methods can also be used. The lower end of the vertical part is spaced a distance from the bottom of the catalyst bed to ensure the outflow of the liquid phase product. The unreacted liquid feed and the reacted but liquid-phase material in the catalyst bed pass through the overflow weir 14, through the outer downcomer 18 (i.e., the annular space between the overflow weir 14 and the inner wall of the gas phase channel 13), along the inverted first umbrella-shaped partition 11, and through the inner downcomer 12 of the next layer into the next catalyst bed. The height of the overflow weir 14 is higher than the upper plane of the catalyst in the bed, preferably 10 to 100 mm higher. The annular outer downcomer 18 formed between the overflow weir 14 and the inner wall of the gas phase channel 13 has a spacing size determined by the size of the liquid phase load, and the size of the downcomer of each bed can be the same or different.

[0052] Further Figure 1 , 3 As shown in FIG. 5 , the gas phase feed subunit includes a gas phase feed pipe 31 and a gas phase distribution pipe 32. The gas phase feed pipe 31 extends in the radial direction of the reaction distillation tower 1. The gas phase distribution pipe 32 is annular (see FIG. Figure 3 , 4 ) or multiple layers of concentric rings (see Figure 5 The gas phase feed pipe 31 is orthogonal to the pipe body 320 of the gas phase distribution pipe 32 (see Figure 3 ) or tangential intersection (see Figure 4 ), a plurality of holes 321 are provided on the wall of the gas phase distribution pipe 32, which are used to evenly distribute the gas phase feed to all directions at the bottom of the catalyst bed. Preferably, but not limiting, the gas phase distribution pipe 32 can be arranged below the catalyst bed, or can be arranged inside the catalyst bed. Figure 6 As shown, the gas-phase feed subunit further includes a gas-phase distribution plate 33, which is located at the bottom of the catalyst bed and is in the shape of a plate as a whole. The gas-phase distribution plate is evenly and densely distributed with a plurality of holes 331. The gas-phase feed enters the reaction distillation tower 1 through the gas-phase feed pipes 31 of each layer, is distributed into the reaction distillation tower 1 through the annular gas-phase distribution pipe 32, and enters the catalyst bed upward through the gas-phase distribution plate 33 at the lower part of the catalyst support plate 19. The gas-phase feed pipe 31 enters the reaction distillation tower 1 in a radial direction, and intersects orthogonally or tangentially with the annular gas-phase distribution pipe 32. The annular gas-phase distribution pipe 32 is located below the catalyst bed. The annular diameter of the annular gas-phase distribution pipe 32 is smaller than the outer ring diameter of the catalyst bed, and the inner diameter is larger than the inner ring diameter of the catalyst bed. The plurality of channels 321 on the wall of the annular gas-phase distribution pipe 32 facilitate the uniform distribution of gas at various positions of the gas-phase distribution plate 33. The function of the catalyst support plate 19 is mainly to support the catalyst bed and ensure that the catalyst bed remains stable in the axial direction of the reaction distillation tower. The function of the gas phase distribution plate 33 is to ensure uniform distribution of the gas phase feed, while trying to avoid direct leakage of the liquid phase feed on the catalyst bed (using the gas phase distribution plate 33 of the present invention, the liquid leakage is less than 15%). When more than one concentric annular gas phase distribution pipe 32 with different diameters is arranged on the same plane, the distribution of the gas phase feed can be more uniform. Figure 1 In the embodiment of the present invention, the annular gas phase distribution pipe 32 is arranged below the catalyst bed layer. When the annular gas phase distribution pipe 32 is installed in the catalyst bed layer, the catalyst support plate 19 can Figure 7 The grid 191 is changed into a support plate, and the gas phase distribution plate 33 is cancelled.

[0053] Further Figure 1 As shown, after the liquid feed and the gas feed react in the catalyst bed layers of each layer, the generated gas phase product directly enters the annular gas phase channel 13 on the side of the tower wall, and the gas phase product passes through the gas phase channel 13 and rises to the inert packing layer 44 of the distillation unit. The lower part of the inert packing layer 44 is provided with a grid-type packing support plate 43 (see Figure 8), the gas phase product from the catalytic reaction unit is distilled here. The feed is converted into the target product (i.e., the gas phase product) through the catalytic reaction unit of the present invention and is promptly separated from the reaction system (the gas phase feed will not be mixed with the gas phase product for secondary reaction), and the gas phase product obtained by the catalytic reaction unit rises to the distillation unit through the gas phase channel 13. One or two or more target products can be obtained through the distillation unit. During the distillation process of the inert filler layer 44, some liquid phase heavy components will be generated. Therefore, the present invention is provided with a guide unit between the inert filler layer 44 and the first catalyst bed layer. The guide unit is a connection device between the distillation unit and the catalytic reaction unit. While collecting the liquid, it can play a role in evenly distributing the gas phase product rising from the catalytic reaction unit. The guide unit is an inverted umbrella-shaped partition structure as a whole (i.e. Figure 1 The second umbrella-shaped partition 41 in the distillation tower is a hollow structure at a position corresponding to the gas phase channel 13 (see Fig. 9 The hollow portion 411 is arranged near the tower wall so that the rising gas phase product from the gas phase channel 13 can smoothly enter the inert seasoning layer 44. The second umbrella-shaped partition 41 is provided with an opening (i.e., a hollow portion 411) near the middle of the distillation tower for the descending liquid phase heavy components after distillation to enter the catalytic reaction unit. Figure 1 and Fig. 9 The liquid phase heavy component collection port 42 in the distillation unit can enter the catalytic reaction unit again through the liquid phase heavy component descending through the distillation unit.

[0054] In the catalytic reaction unit of the present invention, liquid-phase feed and gas-phase feed undergo catalytic reaction in the catalyst bed, gas-phase products and unreacted gas-phase feed rise and leave the reaction system through the gas-phase channel 13, and gas-phase products generated after the reactants undergo chemical reaction in the catalyst bed will leave the reaction zone in time and will not enter the upper catalyst bed (isolated by the inverted umbrella-shaped partition) again, thus avoiding secondary reaction of the target product and improving the selectivity of the reaction. At the same time, due to the departure of the product in the reaction zone, the driving force of the reaction is increased and the equilibrium conversion rate is improved.

[0055] The reaction distillation tower of the present invention uses the above catalytic reaction unit, and the reaction distillation tower 1 can be a multi-layer plate tower structure. The number of catalyst beds in the reaction distillation tower is two or more layers. The reaction distillation tower 1 of the present invention is suitable for a reaction system in which at least one liquid feed and at least one gas feed undergo a chemical reaction on a solid catalyst, and at least one gas product is included in the reaction product. For example, hydrocracking of petroleum fractions and chemical synthetic oils, hydrodewaxing of diesel and lubricating oil fractions, and hydrotreatment processes of various petroleum fractions.

[0056] In addition to the downcomers, overflow weirs and liquid receiving trays 16, each tray of the reaction distillation tower 1 of the present invention is also provided with a liquid sealing baffle on the tray, which is connected to the gas phase channel. Adjacent trays are separated by inverted umbrella-shaped partitions. Each tray is an annular structure, and the outer edge of the annular structure is connected to the gas phase channel. The gas phase channel is a common channel for removing the gas phase products generated by the chemical reaction on each tray. In the embodiment of the present invention, the liquid feed positions are all on the upper part of the first tray, and liquid feed can also be provided on some trays or each tray, and the gas phase feed has feed at the lower part of each tray. Above each tray is a catalyst loading area, and the liquid phase feed flows radially through the catalyst bed. The gas phase feed enters from the bottom of the tray and reacts under the action of the catalyst. The gas phase material generated after the reaction directly leaves the reaction system and enters the gas phase channel on the outside. After the liquid phase leaves the current bed, it enters the next bed through the downcomer. Since the reaction and separation are carried out simultaneously, the reaction equilibrium can be destroyed, and the conversion rate of the reactants and the selectivity of the target product can be effectively improved.

[0057] Example 1

[0058] The catalytic reaction unit of the present invention is used in a hydrocracking reactor in a catalytic diesel hydrocracking process, and a pre-refining reactor is connected in series upstream of the cracking reactor process to remove impurities in the crude oil. The catalyst uses the same catalyst used in industrial devices. The gasoline fraction yield of the cracking product is 50.3%, the gasoline octane number RON is 88.4, and the liquid yield is 91.4%.

[0059] Operating conditions and results:

[0060] Catalytic diesel density 0.9464 g•cm -3 , distillation range 168-370℃;

[0061] Hydrogen purity 99.9%;

[0062] Refined oil nitrogen content 70-100mg.kg -3 ;

[0063] The operating pressure of the catalytic distillation tower is 4.0Mpa;

[0064] Number of catalyst beds in catalytic distillation tower: 1;

[0065] Cracking liquid hourly space velocity LHSV: 1.5h -1 ;

[0066] Hydrogen oil volume ratio: 700:1;

[0067] Average reaction temperature: 350-360℃;

[0068] The gasoline fraction yield is 50.3%; the gasoline octane number RON is 88.4; and the liquid yield is 91.4%.

[0069] Example 2

[0070] The catalytic reaction unit of the present invention is used in a hydrocracking reactor in a catalytic diesel hydrocracking process, and a pre-refining reactor is connected in series upstream of the cracking reactor process to remove impurities in the crude oil. The catalyst uses the same catalyst used in industrial devices and is fixed on the bed with a stainless steel mesh. The yield of the cracking product gasoline fraction is 54.2%, the gasoline octane number RON is 93.5, and the liquid yield is 98.1%.

[0071] Operating conditions and results:

[0072] Catalytic diesel density 0.9464 g•cm -3 , distillation range 168-370℃;

[0073] Hydrogen purity 99.9%;

[0074] Refined oil nitrogen content 70-100mg.kg -3 ;

[0075] The operating pressure of the catalytic distillation tower is 4.0Mpa;

[0076] Catalytic distillation tower catalyst bed number: 10 layers;

[0077] Cracking liquid hourly space velocity LHSV: 1.5h -1 ;

[0078] The load of the first-layer downcomer is designed with 60%-130% operational flexibility according to the feed rate;

[0079] The gas phase feed load of each layer is the same (the gas phase flow rate can also be controlled according to the liquid phase load of each layer);

[0080] The diameter of the gas phase channel is the same at the top and bottom (it can also be set to be larger at the top and smaller at the bottom);

[0081] Hydrogen oil volume ratio: 700:1;

[0082] Average reaction temperature: 350-360℃;

[0083] The gasoline fraction yield was 54.2%, the gasoline octane number RON was 93.5, and the liquid yield was 98.1%. Compared with the single-layer bed in Example 1, when the number of catalyst beds was 10, the effect of the invention was more obvious.

[0084] Example 3

[0085] The catalytic reaction unit of the present invention is used in a hydrocracking reactor in a catalytic diesel hydrocracking process, and a pre-refining reactor is connected in series upstream of the cracking reactor process to remove impurities in the crude oil. The catalyst uses the same catalyst used in industrial devices and is fixed on the bed with a stainless steel mesh. The gasoline fraction yield is 55.1%, the gasoline octane number RON is 93.4, and the liquid yield is 98.5%.

[0086] Operating conditions and results:

[0087] Catalytic diesel density 0.9464 g•cm -3 , distillation range 168-370℃;

[0088] Refined oil nitrogen content 70-100mg.kg -3 ;

[0089] The operating pressure of the catalytic distillation tower is 6.0Mpa;

[0090] Catalytic distillation tower catalyst bed number: 10 layers;

[0091] Liquid hourly space velocity LHSV: 1.5h -1 ;

[0092] The load of the first-layer downcomer is designed with 60%-130% operational flexibility according to the feed rate;

[0093] The gas phase feed load of each layer is the same (the gas phase flow rate can also be controlled according to the liquid phase load of each layer);

[0094] The diameter of the gas phase channel is the same at the top and bottom (it can also be set to be larger at the top and smaller at the bottom);

[0095] Hydrogen oil volume ratio: 800:1;

[0096] Average reaction temperature: 360-380℃;

[0097] The gasoline fraction yield is 55.1%; the gasoline octane number RON is 93.4; and the liquid yield is 98.5%.

[0098] Example 4

[0099] The catalytic reaction unit of the present invention is used in the hydrocracking reactor of the VGO hydrocracking process, and a pre-refining reactor is connected in series upstream of the cracking reactor process to remove impurities in the crude oil. The catalyst uses the same catalyst used in industrial devices and is fixed on the bed with a stainless steel mesh. The yield of heavy naphtha fraction is 48.7%, the aromatic content of heavy naphtha is 33.5%, and the liquid yield is 98.7%.

[0100] Operating conditions and results:

[0101] Catalytic diesel density 0.9047 g•cm -3 , distillation range 258-532℃;

[0102] Refined oil nitrogen content 50mg.kg -3 ;

[0103] The operating pressure of the catalytic distillation tower is 12.0Mpa;

[0104] Catalytic distillation tower catalyst bed number: 10 layers;

[0105] Liquid hourly space velocity LHSV: 1.4h -1 ;

[0106] The load of the first downcomer is designed according to the feed rate with an operating flexibility of 60%-130%.

[0107] The gas phase feed load of each layer is the same (the gas phase flow rate can also be controlled according to the liquid phase load of each layer);

[0108] The diameter of the gas phase channel is the same at the top and bottom (it can also be set to be larger at the top and smaller at the bottom);

[0109] Hydrogen oil volume ratio: 1200:1;

[0110] Average reaction temperature: 360-380℃;

[0111] The yield of heavy naphtha fraction is 48.7%; the aromatic content of heavy naphtha is 33.5%; and the liquid yield is 98.7%.

[0112] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. Any simple modifications, equivalent changes and modifications made to the above exemplary embodiments should fall within the scope of protection of the present invention.

Claims

1. A catalytic reaction distillation tower, characterized in that: include: A catalytic reaction unit, the catalytic reaction unit further comprising: A catalyst bed layer, which is used to fill a solid catalyst, and starting from the second layer, the upper part of the solid catalyst filled in each catalyst bed layer has an inclined surface; A liquid phase feed subunit is arranged above the topmost first catalyst bed layer, and the liquid phase feed is guided downward to the first catalyst bed layer; A gas-phase feed subunit, which is arranged between the catalyst bed layer of the upper layer and the inclined surface of the lower layer, and the gas-phase feed of each layer enters the catalyst bed layer upward; A gas phase channel, which is relatively isolated from the gas phase feed subunit, and a gas phase product generated after the gas phase feed and the liquid phase feed react in the catalyst bed directly enters the gas phase channel; The distillation unit is arranged on the upper part of the catalytic reaction unit and distills the gas phase product generated by the catalytic reaction unit.

2. The catalytic reaction distillation tower according to claim 1, characterized in that: The gas phase channel is located outside the catalytic reaction unit and is annular and penetrates all the catalyst beds from bottom to top.

3. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The inclined surface is an inverted umbrella-shaped partition structure as a whole.

4. The catalytic reaction distillation tower according to claim 3, characterized in that: An inner downcomer is disposed at the end of the inverted umbrella-shaped partition, and the bottom of the inner downcomer is spaced a distance from the bottom of the catalyst bed, so that the liquid feed enters the catalyst bed in a radial direction.

5. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The catalyst bed comprises: An overflow weir, which is arranged on a side close to the gas phase channel; A liquid sealing baffle is arranged on the upper part of the overflow weir and is used to isolate the gas phase feed from the gas phase product.

6. The catalytic reaction distillation tower according to claim 5, characterized in that: The liquid sealing baffle comprises: a horizontal portion, which is in the shape of an annular flat plate and is located above the overflow weir; The vertical part is cylindrical and is formed integrally with the horizontal part. The lower end of the vertical part is spaced a distance from the bottom of the catalyst bed.

7. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The liquid phase feeding subunit further comprises: a liquid-phase feed pipe extending in a radial direction of the catalytic reaction unit; The liquid phase distribution pipe is annular and intersects the liquid phase feed pipe orthogonally or tangentially. The wall of the liquid phase distribution pipe is provided with a plurality of holes for evenly distributing the liquid phase feed to various positions above the first catalyst bed layer.

8. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The gas phase feeding subunit further comprises: a gas-phase feed pipe extending in a radial direction of the catalytic reaction unit; The gas phase distribution pipe is annular or multi-layered concentric annular. The gas phase distribution pipe intersects the gas phase feed pipe orthogonally or tangentially. A plurality of holes are arranged on the wall of the gas phase distribution pipe for evenly distributing the gas phase feed to all directions at the bottom of the catalyst bed.

9. The catalytic reaction distillation tower according to claim 8, characterized in that: The gas phase feeding subunit also includes: The gas phase distribution plate is located at the bottom of the catalyst bed and is in the shape of a plate as a whole. A plurality of holes are evenly and densely distributed on the gas phase distribution plate.

10. The catalytic reaction distillation tower according to claim 8, characterized in that: The gas phase distribution pipe is arranged below the catalyst bed or in the catalyst bed.

11. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The distillation unit is provided with an inert packing layer, and the rising gas phase product from the gas phase channel is distilled in the inert packing layer.

12. The catalytic reaction distillation tower according to claim 11, characterized in that: A guide unit is provided between the inert filler layer and the first catalyst bed layer, and the guide unit as a whole is an inverted umbrella-shaped partition structure; the partition is a hollow structure at a position corresponding to the gas phase channel on one side close to the distillation tower wall, and an opening is provided on the side of the partition close to the middle of the distillation tower for the liquid phase heavy components descending after distillation to enter the catalytic reaction unit.

13. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The catalytic reaction distillation tower is a multi-layer plate tower structure.

14. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The number of catalyst beds in the catalytic reaction distillation tower is two or more.

15. The catalytic reaction distillation tower according to claim 1 or 2, characterized in that: The catalytic reaction distillation tower is suitable for a reaction system in which at least one liquid-phase feed and at least one gas-phase feed undergo a chemical reaction on a solid catalyst, and the reaction product contains at least one gas-phase product.

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