CN109718722B

CN109718722B - Trickle bed reactor

Info

Publication number: CN109718722B
Application number: CN201711025292.4A
Authority: CN
Inventors: 董松涛; 赵广乐; 杨平; 李明丰; 胡志海
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2017-10-27
Filing date: 2017-10-27
Publication date: 2022-03-11
Anticipated expiration: 2037-10-27
Also published as: CN109718722A

Abstract

The invention relates to the field of reactors with solid particle beds, and discloses a trickle bed reactor, which comprises a reactor shell (10) and a plurality of beds (11), wherein the reactor shell is provided with a feed inlet (100) for feeding raw materials, a discharge outlet (101) for discharging products and a discharge outlet (102) for discharging catalysts, the beds (11) are arranged in the reactor shell (10) and are used for filling the catalysts and are arranged along the height direction of the reactor shell (10), adjacent beds (11) are communicated through a discharge pipe (12), and an opening and closing unit (13) for opening and closing the discharge pipe (12) is arranged on the discharge pipe (12). The trickle bed reactor can reduce the back mixing rate of the catalyst in each bed layer and reduce the back mixing phenomenon of the catalyst.

Description

Trickle bed reactor

Technical Field

The present invention relates to a reactor having a bed of solid particles, in particular a trickle bed reactor.

Background

The reactor is a device for realizing the reaction process and is widely applied to the fields of chemical industry, oil refining, metallurgy and the like. The reactor is used for realizing a liquid phase single phase reaction process and a liquid-liquid, gas-liquid, liquid-solid, gas-liquid-solid and other multi-phase reaction processes. Common reactors include tubular reactors, tank reactors, bubble reactors (also referred to as bubble stirred tanks), stirred tank slurry reactors, tower reactors, and jet reactors. In addition, reactors having a bed of solid particles (also known as packed bed reactors) packed with solid catalyst or solid reactant as the gas and/or liquid passes through a bed of solid particles, either fixed or moving, to effect a heterogeneous reaction process, including fixed bed reactors, fluidized bed reactors, moving bed reactors, and the like, are also included. The fixed bed reactor is mainly used for realizing gas-solid phase catalytic reaction, such as an ammonia synthesis tower, a sulfur dioxide contact oxidizer, a hydrocarbon steam converter and the like, and is different from a fluidized bed reactor and a moving bed reactor in that solid particles are in a static state. Trickle bed reactors, also known as trickle bed reactors, are reactors in which gas and liquid are passed cocurrently through a bed of particulate solid catalyst to carry out a gas-liquid-solid phase reaction process. The trickle-bed reactor is one in which the catalyst is present in a fixed bed, and this reactor can also be considered as a fixed-bed reactor.

In order to adapt to the reaction requirements, a plurality of catalyst beds may be arranged in the reactor, and different catalyst beds are filled with different types of catalysts. For example, in a trickle bed reactor used for hydrocracking, a first bed layer, a second bed layer, a third bed layer and a fourth bed layer can be arranged from top to bottom in sequence, wherein the first bed layer is filled with a hydrofining catalyst, the second bed layer and the third bed layer are both filled with a hydrocracking catalyst, and the fourth bed layer is filled with a hydrocracking catalyst and a post-refining catalyst. After a reaction period, the catalysts loaded in different catalyst beds are unloaded and regenerated sequentially. However, the catalyst in different beds may be mixed with each other to different degrees during the unloading of the catalyst, which is called back-mixing. The back mixing phenomenon of the catalyst greatly influences the regeneration of the catalyst and the filling of the regenerated catalyst, thereby influencing the actual application effect of the catalyst.

At present, the back-mixing phenomenon of the catalyst is mainly avoided by adopting a method of separating the catalyst with different particle sizes by a sieving method, however, the method of separating the catalyst by sieving is not practical as the kinds of the catalyst applied in the reactor are more and more; the second mode is that every bed department all sets up the discharge opening that is linked together with corresponding bed, and then every bed passes through corresponding discharge opening and discharges the reactor with catalyst, and in this kind of mode, owing to set up a plurality of discharge openings, consequently can increase the leak source of reactor, reduced the leakproofness of reactor, especially not be applicable to high-pressure reaction, in addition, adopt above-mentioned second mode to make the structure of reactor complicated, the transformation degree of difficulty is great. In addition, catalyst unloading from the upper part of the reactor, i.e. the reverse process of catalyst loading, is also used to reduce back-mixing. In the process of reversely unloading the catalyst, the catalyst is broken more seriously, and the whole process can cause more catalyst loss; and the time consumption is long, the labor intensity of workers is high, the labor environment is severe, and the production cost is greatly improved due to long time consumption and high labor intensity.

Disclosure of Invention

The invention aims to solve the problem that the catalyst in each bed layer in a trickle bed reactor in the prior art has serious back mixing phenomenon in the unloading process, and provides a trickle bed reactor which can reduce the back mixing rate of the catalyst in each bed layer and reduce the back mixing phenomenon of the catalyst.

In order to achieve the above object, in one aspect, the present invention provides a trickle bed reactor, which includes a reactor housing having a feed inlet through which a raw material enters, a discharge outlet through which a product is discharged, and a discharge outlet through which a catalyst is discharged, and a plurality of beds installed in the reactor housing and arranged in a height direction of the reactor housing for filling the catalyst, wherein adjacent beds are communicated with each other through a discharge pipe, and an opening and closing unit for opening and closing the discharge pipe is installed on the discharge pipe.

Preferably, the opening and closing unit includes a cover plate covering the bottom end opening of the discharge pipe and a driving mechanism for controlling the opening and closing of the cover plate.

Preferably, the drive mechanism comprises: the fixed subassembly, the fixed subassembly including set up in the fixed bolster of the outer wall of discharge tube and with the support frame of fixed bolster separable connection connects the rope, connect the both ends of rope respectively with the outer wall of discharge tube with the support frame is connected, the apron connect in connect the rope to and the tractive rope, the one end of tractive rope connect in the support frame, the other end of tractive rope extends to the discharge opening, the tractive rope makes after receiving the tractive force the support frame with the fixed bolster phase separation drives the apron is putd aside the bottom opening of discharge tube.

Preferably, the fixed bolster with connect through buckle structure between the support frame, wherein, buckle structure including set up in the buckle of fixed bolster and set up in the support frame with buckle matched with bayonet socket, perhaps buckle structure including set up in the buckle of support frame and set up in the fixed bolster with buckle matched with bayonet socket.

Preferably, the outer wall of the discharge pipe is provided with a connecting assembly, and the end part of the connecting rope is connected with the outer wall of the discharge pipe through the connecting assembly.

Preferably, the connecting assembly comprises a cylinder body mounted on the outer wall of the discharge pipe and a rotating shaft rotatably arranged in the cylinder body and connected with the end part of the connecting rope, the central axis of the rotating shaft is perpendicular to the height direction of the reactor shell, and the rotating shaft can drive the connecting rope to wind or extend out of the rotating shaft.

Preferably, the support frame is provided with a connecting ring, and the end of the traction rope is connected with the connecting ring.

Preferably, the cover plate is provided with at least one hole, and the hole has a diameter smaller than the particle diameter of the catalyst.

Preferably, the discharge pipe is provided with a plurality of through holes, the through holes are uniformly distributed along the circumferential direction of the pipe wall of the discharge pipe, and the total area of the through hole parts is 10-90% of the total area of the pipe wall of the discharge pipe.

Preferably, every the bed includes first packing layer, catalyst layer and the second packing layer that from the bottom up set gradually, the pipe of unloading is followed the direction of height of reactor shell extends, the top opening of discharge tube stretches into adjacent upper strata in the bed first packing layer of bed, the bottom opening of discharge tube stretches into the lower floor in the bed second packing layer or catalyst layer.

Preferably, said discharge tubes are plural, with opposite ports between adjacent ones of said discharge tubes being aligned, and each of said pull cords connected to a respective one of said deck plates being individually marked.

Preferably, the feed port is provided with a distributor for diffusing the raw material, and/or the discharge port is provided with a product collector.

Preferably, a solid settler is arranged between the catalyst layer and the second packing layer of the bed layer close to the feed inlet, and/or a distribution plate for uniformly distributing materials is arranged in the reactor shell, the distribution plate is positioned above the corresponding bed layer, and a cold hydrogen tank is arranged between the adjacent bed layers and positioned above the distribution plate.

In the above technical solution, the opening and closing unit is installed on the discharge pipe, so that the unloading time of the catalyst in the corresponding bed layer can be controlled, and thus, the catalysts in a plurality of bed layers can be sequentially unloaded, so that the interference between the catalysts in the plurality of bed layers in the unloading process is reduced, and the back mixing rate of the catalyst in each bed layer is greatly reduced, for example, the back mixing rate of the catalyst in each bed layer can be reduced to 7%, thereby greatly reducing the back mixing phenomenon of the catalyst, facilitating the regeneration of the unloaded catalyst, and simultaneously shortening the interval between reaction periods. In addition, the opening and closing unit can control the flow rate of the catalyst passing through the corresponding discharge pipe.

Drawings

FIG. 1 is a schematic cross-sectional structural view of a trickle bed reactor in accordance with a preferred embodiment of the present invention;

fig. 2 is a schematic view of a preferred structure of an opening and closing unit provided to a discharge tube in the trickle bed reactor shown in fig. 1.

Description of the reference numerals

10-a reactor housing; 100-a feed inlet; 101-a discharge hole; 102-a discharge opening; 11-bed layer; 110-a support beam; 12-a discharge tube; 13-an opening and closing unit; 130-a cover plate; 131-a fixed support; 132-a support frame; 133-connecting ropes; 134-a pulling rope; 136-a cylinder; 137-a rotating shaft; 138-connecting ring; 14-a distributor; 15-a distribution tray; 16-a solids settler; 17-a cold hydrogen tank; 18-product collector.

Detailed Description

In the present invention, the use of directional terms such as "upper, lower, left, right" and "above" are generally understood in conjunction with the orientation shown in the drawings and the orientation in practical use, unless otherwise specified.

The invention provides a trickle bed reactor, which comprises a reactor shell 10 and a plurality of beds 11, wherein the reactor shell 10 is provided with a feed inlet 100 for feeding raw materials, a discharge outlet 101 for discharging products and a discharge outlet 102 for discharging catalysts, the beds 11 are arranged in the reactor shell 10 and are used for filling the catalysts and are arranged along the height direction of the reactor shell 10, adjacent beds 11 are communicated through a discharge pipe 12, and an opening and closing unit 13 for opening and closing the discharge pipe 12 is arranged on the discharge pipe 12. The opening and closing unit 13 is arranged on the discharge pipe 12, so that the unloading time of the catalyst in the corresponding bed layer 11 can be controlled, and thus, the catalysts in the bed layers 11 can be sequentially unloaded from bottom to top, so that the interference of the catalysts in the bed layers 11 in the unloading process is reduced, the back mixing rate of the catalyst in each bed layer 11 is greatly reduced, for example, the back mixing rate of the catalyst in each bed layer 11 can be reduced to 7%, the back mixing phenomenon of the catalyst is greatly reduced, the unloaded catalyst is convenient to regenerate, and the connection among all reaction periods is accelerated. Furthermore, the provision of the opening and closing unit 13 also enables the flow rate of the catalyst through the respective discharge pipes 12 to be controlled. After a reaction period is finished, the introduction amount of the raw materials can be gradually reduced, an inert solvent or replacement oil (gasoline and/or light distillate oil) can be introduced into the trickle bed reactor to reduce the temperature and the pressure of the whole reaction system, in addition, inert gas can be introduced to ensure that the whole reaction system is in the atmosphere of the inert gas, and then, the discharge opening 102 is opened, the catalyst in the bottom bed layer 11 is discharged firstly, after the catalyst in the bottom bed layer 11 is discharged, the opening and closing unit 13 installed at the discharge pipe 12 communicating the bottommost bed layer 11 and the bed layer 11 adjacent to the bottommost bed layer 11 is opened, so that the catalyst in the bed layer 11 adjacent to the bottom bed layer 11 is unloaded, and so on, after the catalyst in the lower bed layer 11 is unloaded, and opening the corresponding opening and closing unit 13 to discharge the catalyst in the adjacent upper bed layer 11. It is to be noted that the bed 11 is preferably packed with a catalyst in solid particulate form, and that different beds 11 may be packed with different catalysts, respectively, in order to improve the properties of the reaction products. In addition, the inlet 100 may be opened at the top wall of the reactor housing 10, the outlet 101 may be opened at the bottom wall of the reactor housing 10, and the outlet 102 may be opened at the bottom wall of the reactor housing 10, preferably, the outlet 102 is located at a position higher than the outlet 101. Wherein, the position where the opening and closing unit 13 is disposed is not particularly limited as long as it can control the catalyst to pass through the discharge pipe 12 or be intercepted, and preferably, the opening and closing unit 13 may be disposed at the bottom end opening of the discharge pipe 12. The material of the discharge pipe 12 is not particularly limited, and may be, for example, stainless steel, ceramic, titanium, zirconium, or the like. The discharge pipe 12 may be located in the middle of the inner cavity of the reactor housing 10, or may be located close to the wall of the reactor housing 10, or may be located at other positions as long as it allows the catalyst to pass through to the next bed 11. In addition, the discharge pipe 12 may be a straight pipe with a uniform pipe diameter, or may be in a state where the pipe diameter of the upper portion is large and the pipe diameter of the lower portion is small, and the shape of the discharge pipe 12 is not specifically limited herein. The discharge tube 12 may be formed integrally, or may be formed by connecting multiple sections of tubes through threads or flanges, or may be formed by connecting multiple sections of tubes through a socket structure, a groove structure, or a ferrule structure. The discharge pipe 12 may be a straight pipe or a bent pipe as long as it allows the catalyst to pass through to the next bed 11.

The structure of the opening and closing unit 13 is not particularly limited as long as it can function to open and close the discharge pipe 12. Preferably, the opening and closing unit 13 may include a cover plate 130 covering the bottom end opening of the discharge pipe 12 and a driving mechanism for controlling the opening and closing of the cover plate 130, and the cover plate 130 can cover the bottom end opening of the discharge pipe 12 or remove the bottom end opening of the discharge pipe 12 under the driving action of the driving mechanism, wherein the driving mode may be selected according to actual requirements, for example, an electric driving mode may be selected.

Referring to fig. 1 and 2, the driving mechanism may include a fixing assembly, a connecting rope 133 and a pulling rope 134, wherein the fixing assembly includes a fixing bracket 131 disposed on an outer wall of the discharge pipe 12 and a support bracket 132 detachably connected to the fixing bracket 131, both ends of the connecting rope 133 are respectively connected to the outer wall of the discharge pipe 12 and the support bracket 132, a cover plate 130 is connected to the connecting rope 133, one end of the pulling rope 134 is connected to the support bracket 132, the other end of the pulling rope 134 extends to the discharge opening 102, and an end portion of the pulling rope 134 may be connected to the support bracket 132 through a connecting ring 138 mounted on the support bracket 132 so that the pulling rope 134 is stably connected to the support bracket 132 and can be firmly connected to the support bracket 132 even if a pulling force is applied thereto. When the trickle bed reactor is still in a reaction cycle, namely the raw materials in the trickle bed reactor are still in a reaction stage, the cover plate connected to the connecting ropes 133 covers the bottom end opening of the discharge pipe 12 under the supporting action of the connecting ropes 133; when the catalyst in the corresponding bed layer 11 needs to be unloaded, a pulling force is applied to the pulling rope 134 at the discharge opening 102, and after the pulling force is applied to the pulling rope 134, the supporting frame 132 is separated from the fixed support 131 and the cover plate 130 is driven to move away from the bottom opening of the discharge pipe 12; when the trickle bed reactor needs to be refilled with catalyst for the next reaction cycle, after the bed layer 11 is completely filled, the supporting frame 132 is connected with the fixed bracket 131 again, and the cover plate 130 covers the bottom end opening of the discharge pipe 12. With the above-mentioned form of the driving mechanism, the pulling rope 134 extending to the discharge opening 102 is pulled, so that the cover plate 130 can be removed from the bottom opening of the discharge tube 12 or be connected with the fixing bracket 131 again through the supporting bracket 132, so that the discharge tube 12 is in a closed state, and therefore, the process of opening the discharge tube 12 is simple and convenient to operate, and more importantly, the driving mechanism is selected without additionally forming a mounting hole on the reactor shell 10, so that the airtightness of the whole trickle bed reactor is not affected by the arrangement of additional components.

When the number of the beds 11 is more than 3, a plurality of discharge pipes 12 may be provided, and correspondingly, a plurality of pulling ropes 134 may be provided, and for convenience of operation, each pulling rope 134 connected to the corresponding cover plate 130 may be respectively marked, wherein the marking manner is not particularly limited, for example, metal ropes of different colors may be selected to be respectively connected to the corresponding cover plate 130, and numbers and/or letters may be marked on the end of each pulling rope 134 located at the discharge port 102, and when the catalyst of one bed 11 needs to be unloaded, the corresponding pulling rope 134 may be pulled. It should also be noted that to facilitate the deployment of the pull cords 134, the pull cords 134 of the discharge tubes 12 disposed in the upper tier are sequentially routed through the interior of the discharge tubes 12 in the lower tier to the discharge opening 102. When the discharge tubes 12 are plural, the opposite ports between the adjacent discharge tubes 12 are aligned, so that the flow of the catalyst is facilitated. In addition, a plurality of, for example, 2, discharge pipes 12 are preferably provided between adjacent beds 11 to improve the catalyst unloading efficiency.

In order to facilitate the connection or disconnection of the fixing bracket 131 and the supporting bracket 132, a snap structure may be provided between the fixing bracket 131 and the supporting bracket 132. Further, the fastening structure may include a fastening disposed on the fixing bracket 131 and a bayonet disposed on the supporting bracket 132 and matched with the fastening. In addition, the fastening structure may include a fastening disposed on the supporting frame 132 and a fastening opening disposed on the fixing bracket 131 and matched with the fastening.

In addition, a coupling assembly may be provided at the outer wall of the discharge pipe 12, and the end of the connection string 133 is coupled to the outer wall of the discharge pipe 12 through the coupling assembly, so that the connection string 133 can be stably coupled to the outer wall of the discharge pipe 12.

Further, the connection assembly may include a cylinder 136 installed on an outer wall of the discharge pipe 12, and a rotating shaft 137 rotatably disposed inside the cylinder 136 and connected to an end of the connection string 133, a central axis of the rotating shaft 137 is perpendicular to a height direction of the reactor shell 10, and rotation of the rotating shaft 137 may drive the connection string 133 to wind around or extend out of the rotating shaft 137. After the bed layer 11 is filled, the rotating shaft 137 rotates, the connecting rope 133 extends out of the rotating shaft 137, the supporting frame 132 is connected with the fixed support 131, the cover plate 130 covers the bottom opening of the discharge pipe 12, when the catalyst in the bed layer 11 needs to be unloaded, the corresponding pulling rope 134 is pulled to separate the supporting frame 132 from the fixed support 131 and drive the cover plate 130 to move away from the bottom opening of the discharge pipe 12, and meanwhile, the rotating shaft 137 rotates to drive the connecting rope 133 to wind the rotating shaft 137, so that after the cover plate 130 is moved away, the length of the connecting rope 133 is properly shortened, and the part connected with the connecting rope 133, such as the cover plate 130, cannot influence the unloading of the catalyst due to the blockage of the opening of the adjacent lower discharge pipe 12. In addition, the whole connecting assembly is simple in structure and convenient to operate by operators.

The cover plate 130 may be formed with at least one hole having a diameter smaller than the particle diameter of the catalyst. By forming the holes in the cover plate 130, the materials, such as gas-liquid materials, in the trickle bed reactor can be uniformly distributed when the whole reaction system is in the reaction stage. The shape of the holes is not particularly limited, and may be, for example, circular, rectangular, square, oval, rhombic, or triangular, or may be pentagonal, hexagonal, or other irregular shapes, or may be a combination of these shapes, and the combination may be any of various shapes of holes, for example, one end of the hole may be circular-arc-shaped, and the other end may be triangular, or may be rice-grain-shaped. In addition, the opening ratio of the cover plate 130, i.e. the ratio of the sum of the areas of the holes to the total area of the cover plate 130, is not particularly limited, and may be selected according to actual requirements. Preferably, the cover plate 130 may be provided with a plurality of uniformly distributed holes.

It should be noted that the material used for the components disposed in the opening and closing unit 13 may be stainless steel, or other high temperature and corrosion resistant materials such as ceramic, metallic titanium, titanium alloy, metallic zirconium, or zirconium alloy. Of course, other materials are also possible, and are not particularly limited herein.

In order to make the material, such as gas-liquid material, in the trickle bed reactor evenly distributed during the reaction cycle, at least one through hole, preferably a plurality of through holes, may be formed in the wall of the discharge pipe 12, and the plurality of through holes are evenly distributed along the circumferential direction of the wall of the discharge pipe 12. When a plurality of the through holes are provided, the total area of the part provided with the through holes, that is, the sum of the areas of all the through holes provided on the discharge pipe 12, may be 10 to 90% of the total area of the pipe wall of the discharge pipe 12, so that the material such as the gas-liquid material is further uniformly distributed in the trickle bed reactor. Further, the total area of the opened through-hole parts, i.e., the sum of the areas of all the through-holes provided on the discharge pipe 12, is preferably 20 to 80% of the total area of the pipe wall of the discharge pipe 12, and further, the total area of the opened through-hole parts, i.e., the sum of the areas of all the through-holes provided on the discharge pipe 12, is preferably 30 to 60% of the total area of the pipe wall of the discharge pipe 12. It will be appreciated that a tube of uniform pore size in a mesh structure may be preferred as the discharge tube 12.

Each bed layer 11 comprises a first packing layer, a catalyst layer and a second packing layer which are arranged from bottom to top in sequence, wherein the first packing layer can be filled with ceramic balls, the catalyst layer can be filled with catalysts, the second packing layer can be filled with ceramic balls or protective agents, preferably protective agents RG series such as RG-10, RG-10A/B/C, RG-20 and RG-30, etc., it is also noted that the packing layers such as the first packing layer can be filled with ceramic balls with different grain diameters, for example, a plurality of ceramic ball layers can be arranged in sequence from bottom to top in the first packing layer to respectively fill ceramic balls with different sizes, the grain diameters of the ceramic balls in the ceramic ball layers become smaller gradually in the plurality of ceramic ball layers from bottom to top, specifically, three-quarter inch diameter ceramic balls in the plurality of ceramic ball layers from bottom to top can be arranged in sequence, One-half inch, one-quarter inch and one-eighth inch ceramic balls, and the ceramic balls in each ceramic ball layer have the same particle size. In addition, the thicknesses of the plurality of ceramic ball layers are the same, and for example, the thicknesses of the plurality of ceramic ball layers can be 200 mm.

Further, the discharge pipe 12 may extend along the height direction of the reactor shell 10, and the top end opening of the discharge pipe 12 extends into the first packing layer of the upper bed 11 in the adjacent bed 11, and the bottom end opening of the discharge pipe 12 extends into the second packing layer or the catalyst layer in the lower bed 11. When the bottom opening of the discharge pipe 12 extends into the catalyst layer in the lower bed layer 11, the back mixing phenomenon of the catalyst can be further reduced, so that the discharged catalyst can be directly regenerated, the efficiency of discharging the catalyst is greatly improved, and the connection between reaction cycles is accelerated.

As shown in fig. 1, the bottommost bed 11 may not be provided with the support beam 110 for supporting the catalyst, but each bed 11 above the bottommost bed 11 is provided with the support beam 110 connected to the inner wall of the reactor shell 10, and a first packing layer, a catalyst layer and a second packing layer sequentially arranged on the support beam 110, and the support beam 110 may be a grid structure. In order to remove solid impurities from the material entering the feed inlet 100, a solid settler 16 may be provided between the bed 11 adjacent to the feed inlet 100, i.e. the catalyst layer of the topmost bed 11, and the second packing layer.

In order to diffuse the raw material entering the inlet 100, a distributor 14 may be installed at the inlet 100, and in addition, a product collector 18 may be installed at the outlet 101 to facilitate the collection of the product. The interior of the reactor shell 10 can be equipped with distribution plates 15 for uniform distribution of the material, the distribution plates 15 being located above the respective bed 11. In addition, a cold hydrogen tank 17 may be disposed between adjacent beds 11 to control the temperature in the trickle bed reactor, thereby allowing the reaction in the reactor to be smoothly performed and extending the service life of the catalyst, and the cold hydrogen tank 17 may be disposed above the distribution plate 15.

The effects of the present invention will be further illustrated by examples.

Examples

Example 1

After the trickle bed reactor has completed a reaction cycle, the amount of feed is gradually reduced and naphtha is also fed into the trickle bed reactor, after which nitrogen is fed into the trickle bed reactor and then the discharge port 102 is opened to discharge the catalyst in each bed 11 in sequence. Wherein the configuration in the trickle bed reactor is as follows:

the reactor shell 10 provided with the feed inlet 100, the discharge outlet 101 and the discharge outlet 102 is roughly cylindrical, the inner diameter of the reactor shell 10 is 2438mm, three beds 11 are arranged in the reactor shell 10, and the three beds are a first bed, a second bed and a third bed from bottom to top in sequence, wherein:

the clear height of the first bed layer is 5300mm, the remaining height of the upper part of the first bed layer is 300mm, and the first bed layer is sequentially provided with a ceramic ball layer with the thickness of 200mm (ceramic balls with the diameter of 1/4 inches are filled in the ceramic ball layer), a catalyst bed layer with the thickness of 4200mm (catalyst C filled in the layer, namely catalyst RN-32V), a ceramic ball layer with the thickness of 200mm (ceramic balls with the diameter of 1/8 inches are filled in the ceramic ball layer), a ceramic ball layer with the thickness of 200mm (ceramic balls with the diameter of 1/4 inches are filled in the ceramic ball layer), a ceramic ball layer with the thickness of 200mm (ceramic balls with the diameter of 1/2 inches are filled in the ceramic ball layer) and a ceramic ball layer with the thickness of 200mm (ceramic balls with the diameter of 3/4 inches are filled in the ceramic ball layer);

the net height of the second bed layer is 5180mm, the upper part of the second bed layer is reserved with a height of 300mm, and the second bed layer is sequentially provided with a ceramic ball layer with a thickness of 180mm (ceramic balls with a diameter of 1/4 inches are filled in the ceramic ball layer), a catalyst bed layer with a thickness of 4000mm (catalyst filled in the layer is marked as catalyst B, namely catalyst RT-1), a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 1/8 inches are filled in the ceramic ball layer), a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 1/4 inches are filled in the ceramic ball layer), a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 1/2 inches are filled in the ceramic ball layer) and a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 3/4 inches are filled in the ceramic ball layer);

the net height of the third bed layer is 7270mm, the upper part of the third bed layer is reserved with a height of 300mm, and the third bed layer is sequentially provided with a protective agent layer with a thickness of 500mm (the protective agent in the layer is RG-30), a catalyst bed layer with a thickness of 5400mm (the catalyst filled in the layer is marked as catalyst A, namely RHC-131), a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 1/8 inches are filled in the ceramic ball layer), a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 1/4 inches are filled in the ceramic ball layer), a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 1/2 inches are filled in the ceramic ball layer) and a ceramic ball layer with a thickness of 200mm (ceramic balls with a diameter of 3/4 inches are filled in the ceramic ball layer);

the discharge pipes 12 are arranged between the adjacent beds 11, the top port of each discharge pipe 12 extends into the ceramic ball layer with ceramic balls with the diameter of 3/4 inches in the upper bed 11 of the adjacent bed 11, the bottom port of each discharge pipe 12 extends into the ceramic ball layer with ceramic balls with the diameter of 1/4 inches in the lower bed 11, the length of each discharge pipe 12 is the same, and the opening and closing unit 13 is arranged on each discharge pipe 12, wherein the opening and closing unit 13 can be the opening and closing unit 13 with the preferred structure (namely the structure shown in fig. 2) provided by the invention.

The catalyst A, the catalyst B and the catalyst C are different types of catalysts respectively.

Comparative example

Comparative example 1

The same trickle bed reactor as in example 1 was used, wherein the open/close unit 13 was not provided on each discharge tube 12, the remaining conditions were the same, and the catalyst in each bed 11 was discharged in the same manner as in example 1.

Test examples

The back-mixing ratios of the catalysts a and B obtained in examples 1 to 5 and comparative example 1 were examined by the following method: the catalyst in the material discharged from each bed 11 was sieved, and since the compositions of the catalysts charged in the respective beds 11 were different from each other, after the catalysts in the respective beds 11 were pulverized, the metal compositions were analyzed to obtain the back-mixing ratios of the respective catalysts, and the results are shown in table 1 below.

TABLE 1

As can be seen from table 1, the back-mixing rate of the catalyst is greatly reduced after the opening and closing unit 13 is disposed on the discharge pipe 12, thereby greatly reducing the back-mixing phenomenon of the catalyst.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple modifications can be made to the technical solution of the invention, including combinations of the individual specific technical features in any suitable way. The invention is not described in detail in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.

Claims

1. A trickle bed reactor, characterized in that the trickle bed reactor comprises a reactor shell (10) provided with a feed inlet (100) for raw materials, a discharge outlet (101) for products and a discharge outlet (102) for catalysts, and a plurality of beds (11) for filling catalysts, which are arranged in the reactor shell (10) and arranged along the height direction of the reactor shell (10), wherein adjacent beds (11) are communicated through a discharge pipe (12), and an opening and closing unit (13) for opening and closing the discharge pipe (12) is arranged on the discharge pipe (12);

the opening and closing unit (13) comprises a cover plate (130) covering the bottom end opening of the discharge pipe (12) and a driving mechanism for controlling the opening and closing of the cover plate (130);

the drive mechanism includes:

a fixing assembly including a fixing bracket (131) provided to an outer wall of the discharge pipe (12) and a support bracket (132) detachably connected to the fixing bracket (131),

a connection rope (133), both ends of the connection rope (133) are respectively connected with the outer wall of the discharge pipe (12) and the support frame (132), the cover plate (130) is connected to the connection rope (133), and

the pulling rope (134), one end of the pulling rope (134) is connected to the supporting frame (132), the other end of the pulling rope (134) extends to the discharge opening (102), and the pulling rope (134) enables the supporting frame (132) to be separated from the fixed support (131) after being subjected to pulling force and drives the cover plate (130) to move away from the bottom end opening of the discharge pipe (12).

2. The trickle bed reactor according to claim 1, wherein the fixed bracket (131) and the support bracket (132) are connected by a snap-fit construction, wherein,

the buckle structure comprises a buckle arranged on the fixed support (131) and a bayonet arranged on the support frame (132) and matched with the buckle, or

The buckle structure comprises a buckle arranged on the support frame (132) and a bayonet arranged on the fixed support (131) and matched with the buckle.

3. The trickle bed reactor according to claim 1, characterized in that the outer wall of the discharge tube (12) is provided with a connection assembly by means of which the ends of the connection cord (133) are connected with the outer wall of the discharge tube (12).

4. The trickle bed reactor according to claim 3, wherein the connection assembly comprises a cylinder (136) mounted on the outer wall of the discharge pipe (12) and a rotating shaft (137) rotatably disposed inside the cylinder (136) and connected with the end of the connection rope (133), the central axis of the rotating shaft (137) is perpendicular to the height direction of the reactor shell (10), and the rotation of the rotating shaft (137) can drive the connection rope (133) to wind around or extend out of the rotating shaft (137).

5. The trickle bed reactor according to claim 1, wherein the support frame (132) has a connection ring (138) mounted thereon, and the end of the pulling rope (134) is connected to the connection ring (138).

6. The trickle bed reactor according to claim 1, wherein the cover plate (130) has at least one hole formed therein, the hole having a diameter smaller than the particle size of the catalyst.

7. The trickle bed reactor according to claim 1, wherein said discharge tube (12) is perforated with a plurality of through holes, said through holes being uniformly distributed along the circumferential direction of the wall of said discharge tube (12), the total area of the perforated portions being 10-90% of the total area of the wall of said discharge tube (12).

8. The trickle bed reactor according to any one of claims 1-5, characterized in that each of the beds (11) comprises a first packing layer, a catalyst layer and a second packing layer arranged in this order from bottom to top, the discharge pipe (12) extends in the height direction of the reactor housing (10), the top opening of the discharge pipe (12) extends into the first packing layer of the upper bed (11) in the adjacent bed (11), and the bottom opening of the discharge pipe (12) extends into the second packing layer or the catalyst layer in the lower bed (11).

9. The trickle bed reactor according to claim 8, wherein said discharge tubes (12) are plural, with opposing ports between adjacent said discharge tubes (12) being aligned, and each of said pull cords (134) attached to a respective said cover plate (130) being individually labeled.

10. Trickle bed reactor according to claim 8, characterized in that a distributor (14) for diffusing the feedstock is installed at the inlet (100) and/or a product collector (18) is installed at the outlet (101).

11. Trickle bed reactor according to claim 8, characterized in that a solid settler (16) is arranged between the catalyst layer and the second packing layer of the beds (11) close to the feed inlet (100) and/or in that the reactor housing (10) is internally provided with a distribution plate (15) for even distribution of the material, the distribution plate (15) being located above the respective bed (11), and in that a cold hydrogen tank (17) is arranged between adjacent beds (11), the cold hydrogen tank (17) being located above the distribution plate (15).