CN115785996A

CN115785996A - Special-shaped hydrogenation reactor

Info

Publication number: CN115785996A
Application number: CN202111059331.9A
Authority: CN
Inventors: 郭兵兵; 赵玉琢; 宣根海; 王晶晶; 刘涛
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2021-09-10
Filing date: 2021-09-10
Publication date: 2023-03-14

Abstract

The invention discloses a special-shaped hydrogenation reactor, which comprises: the reaction cavity has a width-to-height ratio of 2:1-10, and comprises from bottom to top: the hydrogen distribution cavity is provided with a plurality of clapboards in parallel along the vertical direction, the clapboards divide the hydrogen distribution cavity into a plurality of air inlet units, and the bottom of each air inlet unit is provided with at least one hydrogen inlet; a porous catalyst layer, and a liquid distribution assembly that uniformly distributes a liquid feedstock over the porous catalyst layer; the heavy oil bin is arranged at the center of the bottom of the reaction cavity and communicated with the plurality of air inlet units; and a separator disposed at the top center of the reaction chamber. The special-shaped hydrogenation reactor has a large width-to-height ratio and is in a 'slice' form, so that reactants can be uniformly contacted, and reaction products quickly leave a reaction system under the action of countercurrent gas carrying and distillation, so that the yield of a target product can be enhanced, and the reaction depth can be controlled through process parameter conditions.

Description

Special-shaped hydrogenation reactor

Technical Field

The invention relates to the technical field of hydrogenation reaction, in particular to a special-shaped hydrogenation reactor capable of controlling the hydrogenation reaction degree.

Background

With the stricter and stricter standards of fuel oil production, the hydrogenation technology has become the mainstream technology of the fuel oil processing technology. According to different raw oil, the hydrogenation reactor is in the forms of fixed bed hydrogenation, moving bed hydrogenation, suspension bed hydrogenation, boiling bed hydrogenation and the like. Among them, the fixed bed hydrotreating technology is the most mature and the application is the most extensive. More and more fixed bed hydrogenation reactors have some outstanding problems in the hydroprocessing process. Firstly, the operation period of an industrial device cannot reach the expected time, and a bed layer of a reactor is blocked due to raw material problems or reactor problems or filling problems, so that the device cannot be operated finally; secondly, most of raw oil and hydrogen of the fixed bed hydrogenation reactor are operated in parallel flow, so that part of light fractions are over-cracked while the overall yield is improved, and the target yield is too low.

Researchers have made diligent efforts to address the problem of plugging of fixed bed catalyst beds. Patent document CN109985574A, CN109985573A discloses an internal member for improving the uniformity of liquid phase distribution, which reduces the local overheating of the catalyst and solves the problem of coking and blockage of the bed layer. However, the reactor is in the form of a conventional fixed bed, i.e. both the feed oil and the hydrogen are operated co-currently, and increasing the overall yield necessarily results in over-cracking of a portion of the light ends.

Patent document CN109777500a discloses a gas-liquid countercurrent two-stage hydrocracking method, which adopts countercurrent hydrocracking to reduce the amount of cold hydrogen, but still has the problem that three-stage cracked products enter a section of high-activity catalyst again for cracking, and the by-products of hydrogen sulfide and ammonia in the catalyst bed still have great restriction on the cracking reaction. CN111575054A discloses a reaction and separation integrated countercurrent hydrogenation process, which provides a countercurrent hydrogenation process for feeding a catalyst and raw oil and feeding the catalyst and the raw oil under hydrogen, and well solves the problem of catalyst coking, but in the countercurrent contact process, the phenomenon of serious uneven gas-liquid distribution can be generated, the product yield is low, and the catalyst cannot be fully utilized.

The height-diameter ratio (the ratio of the total height to the diameter of a reactor bed) of a traditional fixed bed for hydrogenation reaction is generally 2-10, so that the gas-liquid material is ensured to be fully contacted with the solid catalyst, and the required reaction depth and efficiency are achieved. Dong Fangliang et al, in Yi Bin technolog 1998.1 (total 75), and in "determination of main structural parameters of hydrogenation reactor", it is mentioned that in order to avoid small height-diameter ratio "poor catalyst contact efficiency due to uneven fluid distribution", the height-diameter ratio of traditional fixed bed reactor is more than 4-9 ". Patent document CN109679689 a also mentions that the aspect ratio of the conventional liquid phase hydrogenation reactor is generally 2.5 to 12. The design of the above-mentioned aspect ratio of the hydrogenation reactor bed becomes the solidification recognition of those skilled in the art, and the application of a large amount of industrial practice also proves that the design has rationality and relatively universal adaptability, and the wide industrial success may also result in that the skilled person fails to study more comprehensively and more deeply whether other better choices exist for different types of reactions, and there is no relevant research report for a long time or only a research report that the existing aspect ratio is suitable for the design.

The fluidized bed well solves the problem of low conversion rate of inferior heavy oil, but the operation is very complicated, the gas-solid phase retention time is difficult to control, and the risk of reducing the yield of target products exists.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

One of the purposes of the invention is to provide a special-shaped hydrogenation reactor, so that the reaction depth of raw oil in the hydrogenation reactor can be controlled, and the yield of a target product is improved.

Another object of the present invention is to provide a shaped hydrogenation reactor to alleviate the coking and plugging problems of the reactor bed.

In order to achieve the above object, the present invention provides a heterotype hydrogenation reactor, which comprises: the reaction cavity has a width-to-height ratio of 2:1-10, preferably 3:1-6:1. The reaction chamber sequentially comprises from bottom to top: the hydrogen distribution cavity is provided with a plurality of clapboards in parallel along the vertical direction, the clapboards divide the hydrogen distribution cavity into a plurality of air inlet units, and the bottom of each air inlet unit is provided with at least one hydrogen inlet; a porous catalyst layer, and a liquid distribution assembly that uniformly distributes a liquid feedstock over the porous catalyst layer; the heavy oil bin is arranged at the center of the bottom of the reaction cavity and communicated with the plurality of air inlet units; and a separator disposed at the top center of the reaction chamber.

Unless otherwise specified herein, the aspect ratio refers to the ratio of the width of the reaction chamber to the total height of the reaction chamber.

Furthermore, among the above-mentioned technical scheme, the reaction chamber is horizontal storage tank, and its axial is along transversely setting up, and horizontal storage tank both ends are equipped with the head.

Further, among the above-mentioned technical scheme, the reaction chamber is oblate cylindrical tank, and its axial sets up along vertically, and a plurality of baffles are coaxial annular baffle.

Further, in the above technical solution, each partition plate is distributed with a plurality of round holes.

Further, in the above technical solution, the plurality of partition plates extend upward to the porous catalyst layer, the opening ratio of the partition plate below the porous catalyst layer is less than 70%, and the opening ratio of the partition plate in the porous catalyst layer is greater than 50%.

Further, in the above technical solution, the ratio of the cross-sectional area of the separator to the cross-sectional area of the reaction chamber is 1.2 to 1.

Further, in the above technical scheme, the separator comprises a mixing section, a separation section and a stabilizing section from bottom to top.

Further, in the above technical scheme, the separation section is provided with 1-3 product lateral lines; the mixing section is provided with 1-3 light raw material lateral lines, and the mixing section is provided with 1-3 reaction zones.

Further, among the above-mentioned technical scheme, be equipped with the liquid redistributor between separator and the reaction chamber, the liquid redistributor includes: the distribution disc is arranged above the liquid distribution assembly, the shape of the distribution disc is the same as that of the top surface of the porous catalyst layer, a plurality of first through holes are uniformly formed in the distribution disc, a first overflow ring is arranged around each first through hole, and an overflow part is arranged at the outer edge of the distribution disc; and the distribution cone is arranged in the center of the upper part of the distribution disc, is provided with a plurality of second through holes, and is provided with a second overflow ring around the second through holes.

Furthermore, in the above technical scheme, the aperture ratio of the distribution disc is 5-90%, the diameter of the first through hole is 5-100 mm, and the height of the first overflow ring is 1-30 mm; the vertex angle of the distribution cone is more than 90 degrees, the aperture ratio of the distribution cone is 5-80 percent, and the height of the second overflow ring is 1-30 mm; the bottom area of the distribution cone is 2-15% of the area of the distribution disc, and the area of the distribution disc is 50-100% of the area of the top surface of the porous catalyst layer.

Further, among the above-mentioned technical scheme, the inboard of first overflow ring is equipped with sawtooth portion, and sawtooth portion is crooked downwards, is equipped with the guiding gutter on the sawtooth portion.

Further, in the above technical scheme, a gas distributor is arranged at the hydrogen inlet.

Further, in the above technical scheme, the heterotypic hydrogenation ware still includes: and one end of the reboiler is connected with an outlet of the heavy oil bin, and the other end of the reboiler is connected with the hydrogen distribution cavity.

Further, in the above technical scheme, the heterotypic hydrogenation ware still includes: multistage auxiliary reaction chamber, each level auxiliary reaction chamber advance hydrogen alone, the bottom center sets up heavy oil storehouse alone, and the liquid raw material import of each level auxiliary reaction chamber is connected with the heavy oil storehouse of last one-level, and the top of multistage auxiliary reaction chamber all is connected to the separator.

Further, in the above technical scheme, the porosity of the porous catalyst layer is 15% -85%.

Further, in the above technical scheme, when the porous catalyst of the porous catalyst layer is a raschig ring or a honeycomb body, the equivalent pore diameter of the porous catalyst is 1-30 mm.

Compared with the prior art, the invention has one or more of the following advantages:

1. the special-shaped hydrogenation reactor has a large width-to-height ratio and is in a 'slice' form, so that reactants can be uniformly contacted, raw oil and hydrogen are in countercurrent contact in a catalyst layer, reaction products quickly leave a reaction system under the action of countercurrent gas carrying and distillation, the yield of target products can be enhanced, and the reaction depth can be controlled through process parameter conditions.

2. The conventional fixed bed type is a plug flow type reactor, and the plug flow type has the advantage that each catalyst can be fully utilized by performing plug flow in a long distance. Most hydrogenation catalysts are noble metal catalysts and are expensive, so that technical improvement is basically carried out on the basis of a reactor with a large height-diameter ratio by a person skilled in the art. The catalyst layer of the special-shaped hydrogenation reactor is arranged in a 'slice' form, and the effect of uniform gas-liquid contact is ensured from two aspects, namely, the gas-liquid distribution design; and secondly, a porous catalyst is selected to ensure the void ratio and avoid the phenomenon of channeling.

3. The special-shaped hydrogenation reactor couples the reaction cavity with distillation, raw oil directly obtains light distillate oil and heavy distillate oil after passing through the reactor, and a special fractionating tower is not required to be arranged for separation, so that the investment and the energy consumption are saved. Meanwhile, the heat generated in the hydrogenation reaction process is needed in the distillation process, and the heat energy is also saved. The distillation process is mostly applied to lower pressure or vacuum, and the distillation process under the condition of high-pressure hydrogenation in 8 MPaG-16 MPaG is generally considered to not achieve the expected effect. However, by the design of the invention, although the light hydrocarbons cracked under high pressure are in liquid form, the light hydrocarbons can still easily leave the reaction system under the action of stripping, and the expected distillation effect is achieved.

4. The flux of the porous catalyst layer of the special-shaped hydrogenation reactor is greatly increased compared with that of the traditional fixed bed reactor.

5. The liquid redistributor can disperse the passing liquid into small liquid drops, and by means of the stripping action of hydrogen, the lighter part is directly taken away from the reactor, and the heavier part downwards enters a hydrocracking reaction zone under the action of gravity, so that the excessive cracking of the light component is avoided.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood and to make the technical means implementable in accordance with the contents of the description, and to make the above and other objects, technical features, and advantages of the present invention more comprehensible, one or more preferred embodiments are described below in detail with reference to the accompanying drawings.

Drawings

Figure 1 is a schematic diagram of the structure of a profiled hydrogenation reactor according to an embodiment of the present invention.

Figure 2 is a schematic diagram of the structure of a profiled hydrogenation reactor according to another embodiment of the present invention.

Figure 3 is a schematic diagram of the structure of a profiled hydrogenation reactor according to yet another embodiment of the present invention.

Fig. 4 is a side view of a segmental baffle according to an embodiment of the invention.

Fig. 5 is a side view schematically illustrating a segmental baffle according to another embodiment of the invention.

Fig. 6 is a schematic top view of an annular partition according to an embodiment of the present invention.

Fig. 7 is a side view schematically illustrating an annular partition according to another embodiment of the present invention.

FIG. 8 is a side view of an annular partition in accordance with an embodiment of the present invention.

Fig. 9 is a schematic top view of a liquid redistributor according to an embodiment of the present invention.

Fig. 10 is a schematic top view of a liquid redistributor according to another embodiment of the present invention.

Fig. 11 is a side view of the liquid redistributor shown in fig. 10.

Fig. 12 is a schematic top view of a first overflow ring according to an embodiment of the invention.

Fig. 13 is a perspective view of the first overflow ring of fig. 12.

Description of the main reference numerals:

10-reaction chamber, 101-end socket, 111-partition board, 111 a-segmental partition board, 111 b-annular partition board, 1111-round hole, 112-air inlet unit, 113-hydrogen inlet, 12-porous catalyst layer, 13-liquid distribution component, 20-separator, 21-mixing section, 211-light raw material lateral line, 212-reaction zone, 22-separation section, 221-product lateral line, 23-stabilizing section, 30-heavy oil bin, 40-liquid redistributor, 41-distribution disk, 411-first through hole, 412-first overflow ring, 4121-sawtooth part, 4122-diversion groove, 42-distribution cone, 421-second through hole, 422-second overflow ring, 50-reboiler and 60-auxiliary reaction chamber.

Detailed Description

Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.

Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.

Spatially relative terms, such as "below," "lower," "upper," "above," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the figures. For example, if the items in the figures are turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the elements or features. Thus, the exemplary term "below" can encompass both an orientation of below and above. The articles may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.

In this document, the terms "first", "second", etc. are used to distinguish two different elements or portions, and are not used to define a particular position or relative relationship. In other words, the terms "first," "second," and the like may also be interchanged with one another in some embodiments.

As shown in fig. 1, the special-shaped hydrogenation reactor according to the embodiment of the present invention comprises, from bottom to top, a heavy oil bin 30, a reaction chamber 10 and a separator 20. The reaction chamber 10 is a flat structure with a large width-height ratio, and the width-height ratio can be 2:1-10, preferably 3:1-6:1. The reaction chamber 10 comprises a hydrogen distribution chamber, a porous catalyst layer 12 and a liquid distribution assembly 13 from bottom to top in sequence. The hydrogen distribution chamber is divided into a plurality of gas inlet units 112 by a plurality of partition plates 111 arranged in parallel in the vertical direction, and the bottom of each gas inlet unit 112 is provided with at least one hydrogen inlet 113. The liquid distribution member 13 can uniformly distribute the liquid raw material on the porous catalyst layer 12. The heavy oil sump 30 is disposed at the bottom center of the reaction chamber 10 and communicates with a plurality of air inlet units 112. The separator 20 is disposed at the top center of the reaction chamber 10. Further, in one or more exemplary embodiments of the present invention, a gas distributor (not shown in the drawings) may be provided at the hydrogen inlet 113.

Further, in one or more exemplary embodiments of the present invention, the reaction chamber 10 may be a horizontal tank, as shown in fig. 1, which is disposed axially and transversely, and has a sealing head 101 at both ends. Further, in one or more exemplary embodiments of the present invention, the reaction chamber 10 may also be a flat cylindrical tank, which is axially disposed in the longitudinal direction.

Further, in one or more exemplary embodiments of the present invention, the partition 111 has a shape matching the bottom of the reaction chamber 10, and when the reaction chamber 10 is a horizontal tank, the partition 111 is a segmental partition 111a, as shown in fig. 4 and 5; when the reaction chamber 10 is a flat cylindrical tank, the plurality of partition plates 111 are coaxial annular partition plates 111b, as shown in FIGS. 6 to 8. Further, in one or more exemplary embodiments of the present invention, a plurality of circular holes 1111 are distributed on each of the separators 111 (the segmental separator 111a or the annular separator 111 b). Further, in one or more exemplary embodiments of the present invention, as shown in fig. 5 and 8, a plurality of partition plates may extend upward to the porous catalyst layer 12, and the partition plates not in contact with the porous catalyst layer 12 at the bottom have an opening ratio of less than 70%, and a lower opening ratio is advantageous for increasing the resistance so that hydrogen gas enters the porous catalyst layer 12 as upward as possible, further functioning as a gas distributor. The open area ratio of the partition plates in the porous catalyst layer 12 is more than 50%, which is advantageous for more fully utilizing the catalyst.

Further, in one or more exemplary embodiments of the present invention, the ratio of the cross-sectional area of the separator 20 to the reaction chamber 10 is 1.

Further, in one or more exemplary embodiments of the present invention, the separator 20 includes, from bottom to top, a mixing section 21, a separation section 22, and a stabilization section 23. Illustratively, the separation section 22 is provided with 1-3 product sidedraws 221; the mixing section 21 is provided with 1-3 light raw material lateral lines 211, and the mixing section 21 is provided with 1-3 reaction zones 212. Further, in one or more exemplary embodiments of the present invention, under the action of the porous catalyst layer 12 of the reaction chamber 10 and under a certain temperature and pressure, the raw oil and hydrogen react to produce smaller molecular hydrocarbons or other gases, which are rapidly carried by the hydrogen gas to the mixing section 21 of the separator 20, and through the separation action of the mixing section 21 and the separation section 22, a part of the heavier fraction uniformly falls down to the surface of the porous catalyst layer 12 of the reaction chamber 10 through the liquid redistributor 40. Another portion of the light fraction continues in the separation section 22 towards a stabilization section 23 at the top of the separator 20. The product of the desired fraction can be obtained in the separation section 22 via a product side line 221. Heavy fractions which are not available for reaction in the reaction chamber 10 are collected into the heavy oil bin 30 at the bottom, part of the heavy oil can be used as a chemical raw material product, and part of the heavy oil can be gasified by circulating through the reboiler 50 and enter the reaction chamber 10. Illustratively, one end of the reboiler 50 is connected to the outlet of the heavy oil bin 30, and the other end is connected to the hydrogen distribution chamber.

Further, in one or more exemplary embodiments of the present invention, the liquid redistributor 40 between the separator 20 and the reaction chamber 10 includes a distribution disk 41 and a distribution cone 42. The distribution plate 41 is disposed above the liquid distribution assembly 13, the distribution plate 41 has the same shape as the top surface of the porous catalyst layer 12, a plurality of first through holes 411 are uniformly formed in the distribution plate 41, a first overflow ring 412 is disposed around the first through holes 411, and an overflow portion (not shown) is disposed on the outer edge of the distribution plate 41. The distribution cone 42 is disposed at the upper center of the distribution plate 41, the distribution cone 42 is provided with a plurality of second through holes 421, and a second overflow ring (not shown) is disposed around the second through holes 421.

Further, in one or more exemplary embodiments of the present invention, the opening ratio of the distribution plate 41 is 5% to 90%, the diameter of the first through hole 411 is 5mm to 100mm, the height of the first overflow ring 412 is 1mm to 30mm, and the height of the overflow portion of the edge of the distribution plate 41 may be the same as the height of the first overflow ring 412, which is not limited thereto. The apex angle of the distribution cone 42 is greater than 90 deg., the flatter the apex angle of the distribution cone 42 the better, so that the flow rate of the liquid droplets in the distribution tray 41 can be made flatter. The aperture ratio of the distribution cone 42 is 5-80%, and the height of the second overflow ring is 1-30 mm; the bottom area of the distribution cone 42 is 2% to 15% of the area of the distribution disk 41, and the area of the distribution disk 41 is 50% to 100% of the area of the top surface of the porous catalyst layer 12. The distribution cone 42 prevents the liquid returning from the separator 20 from flowing down all the way through the first through hole 411 at the center of the distribution plate 41, making the liquid distribution more uniform.

Preferably, but not by way of limitation, in one or more exemplary embodiments of the present invention, as shown in fig. 12 and 13 in combination, the inner side of the first overflow ring 412 is provided with serrations 4121, the serrations 4121 are bent downward, and the serrations 4121 are provided with guide grooves 4122. Exemplarily, the flow guide groove 4122 is opened along the center of the serration 4121.

As shown in connection with fig. 3, in one or more embodiments of the present invention, the profiled hydrogenation reactor further comprises an auxiliary reaction chamber 60. It should be understood that the auxiliary reaction chamber 60 shown in fig. 3 is one stage, the present invention is not limited thereto, and the auxiliary reaction chamber 60 may be multi-stage. Each stage of the auxiliary reaction cavity 60 separately enters hydrogen, the bottom center is separately provided with a heavy oil bin, the liquid raw material inlet of each stage of the auxiliary reaction cavity 60 is connected with the heavy oil bin of the previous stage, and the top of each stage of the auxiliary reaction cavity is connected to the separator 20.

Further, in one or more exemplary embodiments of the present invention, the porosity of the porous catalyst layer 12 is 15% to 85%.

Further, in one or more exemplary embodiments of the present invention, when the porous catalyst of the porous catalyst layer 12 is a raschig ring or a honeycomb body, the equivalent pore diameter of the porous catalyst is 1 to 30mm.

The profiled hydrogenation reactor of the present invention is described in more detail below by way of specific examples, it being understood that the examples are exemplary only and the invention is not limited thereto.

Example 1

Referring to fig. 1 and 4, in the present embodiment, a special-shaped hydrogenation reactor is used to perform a diesel hydrocracking process, a reaction chamber 10 is in a horizontal storage tank structure, and a hydrogen distribution chamber is divided into a plurality of air inlet units 112 by segmental baffles 111 a. The catalyst filled in the porous catalyst layer 12 is a porous cracking agent which is prepared by preparing active components into a Raschig ring shape of 4 mm. The thickness of the porous catalyst layer 12 is 1/4 of the equivalent diameter of the cross section, the area of the distribution plate 41 of the liquid redistributor 40 is 70% of the top surface of the porous catalyst layer 12, the first through holes 411 of the distribution plate 41 have a hole diameter of 5mm and an opening ratio of 50%. The sectional area of the separator 20 is 1/5 of the maximum sectional area of the reaction chamber 10, and the ratio of the separation section 22 in the separator 20 is 50%.

The process of the embodiment is as follows: diesel oil enters the reaction chamber 10 from the liquid distribution assembly 13, hydrogen enters each gas inlet unit 112 from the hydrogen inlet 113 and upwards enters the porous catalyst layer 12, and after the diesel oil and the hydrogen react in the porous catalyst layer 12, light components upwards enter the separator 20 to finally generate a naphtha product; the heavy components are collected in the heavy oil sump 30 and recycled back to the liquid distribution assembly 13.

The properties of the raw materials and the operating conditions of this example are shown in table 1, and the change in the simulated temperature rise of the porous catalyst layer 12 is shown in table 2. See table 3 for product properties.

Example 2

Referring to fig. 2, fig. 6 and fig. 8, in the present embodiment, a special-shaped hydrogenation reactor is used for performing a diesel hydrocracking process, the reaction chamber 10 adopts a flat cylindrical tank structure, and the hydrogen distribution chamber is divided into a plurality of air inlet units 112 by an annular partition 111 b. The catalyst filled in the porous catalyst layer 12 is a porous cracking agent which is prepared by preparing active components into a Raschig ring shape of 4 mm. The thickness of the porous catalyst layer 12 is 1/4 of the equivalent diameter of the cross section, the area of the distribution disk 41 of the liquid redistributor 40 is 70% of the top surface of the porous catalyst layer 12, the first through holes 411 of the distribution disk 41 have a pore diameter of 5mm and an opening ratio of 50%. The diameter of the separator 20 is 1/5 of the equivalent diameter of the reaction chamber 10, and the separation section 22 in the separator 20 is provided with 10% of the reaction zone 212.

The process of this example differs from that of example 1 in that the light components enter the separator 20 upward, and moderate cracking is continued to finally produce a naphtha product; the heavy components are collected in the heavy oil sump 30 and recycled back to the liquid distribution assembly 13.

Comparative example 1

This comparative example used a conventional plug flow type fixed bed reactor.

The feed properties and operating conditions of this comparative example are shown in Table 1, and the simulated temperature rise of the catalyst bed is shown in Table 2. See table 3 for product properties.

TABLE 1 Properties of the stock oils and operating conditions

The bed reaction temperature profiles of examples 1-2 and comparative example 1 were calculated by simulation in the laboratory using ansys version 19.0 software. The simulation conditions were input according to the actual data of examples and comparative examples. Simulation results show that the traditional fixed bed has the highest central temperature, and the temperature change is normally distributed from the inlet end to the outlet end. The simulated temperature rise of the bed is shown in Table 2. As can be seen from table 2, the temperature difference of the catalyst bed layer was significantly lower than that of comparative example 1 by using the special-shaped hydrogenation reactors of examples 1 and 2 of the present invention. For example, in example 2, the temperature difference in the upper bed was reduced from 18.4 ℃ in the conventional fixed bed to 0.4 ℃ and the temperature difference in the lower bed was reduced from 28.5 ℃ in the conventional fixed bed to 0.5 ℃. The difference between the average temperature and the control temperature is minimum in the embodiment, the average temperature difference between the upper part and the lower part of the embodiment is only 0.04-0.12 ℃, and the average temperature difference between the upper part and the lower part of the embodiment reaches 10.2 ℃, so that the overheating phenomenon of the hydrocracking reaction is eliminated by the reactor disclosed by the invention, and the reaction temperature can be controlled more accurately.

The special-shaped hydrogenation reactor can directly produce naphtha products, and distillate oil cracked by the traditional plug flow type fixed bed reactor needs to enter a next fractionating tower for fractionation so as to cut naphtha fraction and diesel oil.

As can be seen from table 3, the yield of heavy naphtha of example 1 is significantly increased as compared to comparative example 1, and the selectivity of heavy naphtha is 90% or more. Example 2 light naphtha selectivity increases after the separation section increases the cracking section. The light naphtha is used as cracking material for producing ethylene, and the heavy naphtha can be used as high-quality heavy monolith with high aromatic hydrocarbon content. The comparative example using a conventional reactor generally increases the naphtha yield by increasing the pressure or temperature, but this in turn increases the depth of the cracking reaction and the selectivity becomes poor.

TABLE 2 simulated temperature rise change of catalyst bed

Temperature point of bed layer	Example 1	Example 2	Comparative example 1
				Upper part
Maximum radial temperature difference, ° c	1.1	0.4	18.4
				Average temperature of	371.66	371.32	380.74
Lower part
				Maximum radial temperature difference, ° c	1	0.5	28.5
Average temperature of	371.7	371.44	390.94
				Longitudinal temperature difference of DEG C	0.04	0.12	10.2

TABLE 3 Properties of the product

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications. Any simple modifications, equivalent changes and modifications made to the above exemplary embodiments shall fall within the scope of the present invention.

Claims

1. A profiled hydrogenation reactor, comprising:

the reaction cavity has a width-to-height ratio of 2:1-10, and comprises from bottom to top:

the hydrogen distribution chamber is provided with a plurality of clapboards in parallel along the vertical direction, the clapboards divide the hydrogen distribution chamber into a plurality of air inlet units, and the bottom of each air inlet unit is provided with at least one hydrogen inlet;

a porous catalyst layer, and

a liquid distribution assembly that uniformly distributes a liquid feedstock over the porous catalyst layer;

the heavy oil bin is arranged at the center of the bottom of the reaction cavity and communicated with the plurality of air inlet units; and

a separator disposed at a top center of the reaction chamber.

2. The special-shaped hydrogenation reactor according to claim 1, wherein the reaction chamber is a horizontal storage tank, the axial direction of the horizontal storage tank is arranged along the transverse direction, and sealing heads are arranged at two ends of the horizontal storage tank.

3. The special-shaped hydrogenation reactor according to claim 1, wherein the reaction chamber is an oblate cylindrical tank which is axially and longitudinally arranged, and the plurality of baffles are coaxial annular baffles.

4. The profiled hydrogenation reactor of claim 1 wherein a plurality of circular holes are distributed on each of the baffles.

5. The profiled hydrogenation reactor of claim 4 wherein the plurality of baffles extend up to the porous catalyst layer, the baffles below the porous catalyst layer having an open porosity of less than 70 percent and the baffles within the porous catalyst layer having an open porosity of greater than 50 percent.

6. The profiled hydrogenation reactor of claim 1 wherein the ratio of the cross-sectional area of the separator to the reaction chamber is from 1.2 to 1.

7. The profiled hydrogenation reactor of claim 1 wherein the separator comprises, from bottom to top, a mixing section, a separation section, and a stabilization section.

8. The profiled hydrogenation reactor of claim 7 wherein the separation section is provided with 1-3 product side lines; the mixing section is provided with 1-3 light raw material lateral lines, and the mixing section is provided with 1-3 reaction zones.

9. The profiled hydrogenation reactor of claim 1 wherein a liquid redistributor is disposed between the separator and the reaction chamber, the liquid redistributor comprising:

the distribution disc is arranged above the liquid distribution assembly, the shape of the distribution disc is the same as that of the top surface of the porous catalyst layer, a plurality of first through holes are uniformly formed in the distribution disc, a first overflow ring is arranged around the first through holes, and an overflow part is arranged at the outer edge of the distribution disc; and

the distribution cone is arranged in the center of the upper part of the distribution disc, a plurality of second through holes are formed in the distribution cone, and a second overflow ring is arranged around the second through holes.

10. The special-shaped hydrogenation reactor according to claim 9, wherein the opening rate of the distribution disc is 5-90%, the diameter of the first through hole is 5-100 mm, and the height of the first overflow ring is 1-30 mm; the vertex angle of the distribution cone is more than 90 degrees, the aperture ratio of the distribution cone is 5-80 percent, and the height of the second overflow ring is 1-30 mm; the bottom area of the distribution cone is 2-15% of the area of the distribution disc, and the area of the distribution disc is 50-100% of the area of the top surface of the porous catalyst layer.

11. The special-shaped hydrogenation reactor according to claim 9, wherein the inner side of the first overflow ring is provided with a sawtooth part, the sawtooth part is bent downwards, and a diversion trench is arranged on the sawtooth part.

12. The profiled hydrogenation reactor of claim 1 wherein a gas distributor is provided at the hydrogen inlet.

13. The profiled hydrogenation reactor of claim 1 further comprising:

and one end of the reboiler is connected with the outlet of the heavy oil bin, and the other end of the reboiler is connected with the hydrogen distribution cavity.

14. The profiled hydrogenation reactor of claim 1 further comprising:

the multi-stage auxiliary reaction cavity, each grade the auxiliary reaction cavity advances hydrogen alone, the bottom center sets up heavy oil storehouse alone, each grade the liquid raw material import of auxiliary reaction cavity is connected with the heavy oil storehouse of last one-level, the top of multi-stage auxiliary reaction cavity all is connected to the separator.

15. The profiled hydrogenation reactor of claim 1 wherein the porosity of the porous catalyst layer is between 15% and 85%.

16. The heterogeneous hydrogenation reactor of claim 15 wherein when the porous catalyst of the porous catalyst layer is a Raschig ring or a honeycomb body, the equivalent pore size of the porous catalyst is 1-30 mm.