Fluidized bed reactor with accurate control function for propane dehydrogenation

Abstract

The invention discloses a fluidized bed reactor for propane dehydrogenation with an accurate control function, which mainly comprises an expansion section, a reaction section and a gas inlet tail section which form a straight cylindrical reactor from top to bottom, a sealing plate is arranged at the upper part in the expansion section, and a gas return space is formed above the sealing plate; a plurality of exhaust valves in a circumferential array are mounted outside the expansion section and are communicated with the air return space, and a feeding pipe is mounted below one side of the outside of the expansion section. The reactor has the advantages that the reactor is divided into the expanding section, the reaction section and the gas inlet tail section from top to bottom, the expanding section, the reaction section and the gas inlet tail section form a straight barrel shape through flange structures, the distribution plate is mounted in the reaction section, and the gas collecting conical barrel capable of reciprocating up and down is mounted in the reaction section, so that gas after reaction can be discharged from the gas collecting conical barrel; the internal space of the reaction section can be changed by adjusting the vertical position of the gas collection cone, so that certain fluid pressure is generated between the gas collection cone and a reactant, and the effect of controlling the reaction process is realized.

Description

Technical Field

[0001] The invention relates to the technical field of petrochemical industry, in particular to a fluidized bed reactor for propane dehydrogenation with a precise control function. Background Art

[0002] Propane dehydrogenation refers to the production of propylene monomer by dehydrogenation of propane, which is an important way to produce propylene.

[0003] Fluidized bed reactor refers to a device in which gas undergoes chemical reaction in a fluidized bed composed of solid materials or catalysts. It is also called "fluidized bed reactor". Within a certain flow rate range, the gas will strongly stir the solid fine particles of catalyst or material piled into a certain thickness (bed), making it like a boiling liquid and having some characteristics of liquid, such as fluid pressure on the vessel wall, overflow and viscosity. This operating condition is called "fluidized bed". At present, the industrialized dehydrogenation catalyst systems are mainly Cr2O3 / Al2O3 system and Pt / Al2O3 system. The industrialized Pt-based propane dehydrogenation processes mainly include UOP's Oleflex process, Wood's STAR process and Linde-BASF PDH process. The advantage of the Oleflex moving bed process is that the reactor operates continuously and there is no need to stop the reaction for catalyst regeneration. However, the equipment investment cost of this process is relatively high, and the catalyst circulates between 4 to 5 reactors and the regenerator, resulting in high catalyst attrition rate and large reaction fluctuations. In addition, the propane conversion rate and propylene selectivity are restricted by the reaction conditions, and the propylene yield has always been low. The STAR process and the Linde-BASF PDH process both use shell-and-tube fixed-bed dehydrogenation reactors, which have the advantages of low catalyst usage and in-vessel regeneration, complex reactor design, frequent switching, and high requirements for valves.

[0004] As for Pt-based catalysts, the mass and heat transfer in the fixed dehydrogenation process is uneven and the carbon deposition is high. Therefore, there is currently no industrial device for the Pt-based dehydrogenation system. The catalysts in the moving bed and circulating fluidized bed need to circulate in the entire reaction system, with high attrition rate and poor control stability. Based on this, the present application proposes a fluidized bed reactor for propane dehydrogenation with precise control function to solve the above problems. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides a fluidized bed reactor for propane dehydrogenation with a precise control function to solve the problems mentioned in the background technology and overcome the deficiencies in the prior art.

[0007] (II) Technical solution

[0008] In order to solve the above-mentioned related problems and achieve the desired purpose, the present invention provides the following technical solutions: a fluidized bed reactor for propane dehydrogenation with precise control function, comprising an expansion section, a reaction section and an air intake tail section, the three of which form a straight cylindrical reactor from top to bottom, a closing plate is installed above the inside of the expansion section, and a return air space is formed above it, a plurality of exhaust valves in a circumferential array are installed outside the expansion section, which are communicated with the return air space, a feed pipe is installed below one side of the outside of the expansion section, which is located below the return air space, a plurality of first telescopic motors in a circumferential array are installed on the bottom surface of the closing plate, and a cone seat is installed at the output end thereof, and an air collecting cone that can reciprocate up and down is installed above the inside of the reaction section, with its large mouth facing downward and the tip of the outside being arranged A fixed cylinder is installed, and a plurality of air outlets are opened on the upper part of the outside of the fixed cylinder. The fixed cylinder passes through the closing plate, and the two are slidably matched. The plurality of air outlets are all located in the return air space, and a plurality of cone cylinders in a circumferential array are installed at the edge below the air collecting cone, and their positions are respectively adapted to the positions of a plurality of cone seats. A heat exchange component is installed below the inside of the reaction section, and an inlet valve and an outlet valve are respectively installed on the outside of the heat exchange component. A distribution plate is installed at the bottom of the reaction section, and an air intake pipe is installed at the midline of the inside of the air intake tail section, and a first air intake valve is installed at the outer end thereof. A plurality of fixed pipes in a circumferential array are installed on the side wall inside the air intake tail section, and a plurality of one-way valves in a uniform array are installed on the outside of the plurality of fixed pipes, and their air outlet directions are toward the distribution plate.

[0009] Preferably, a plurality of assembly pipes in a circular array are installed above the outer surface of the expansion section, which are communicated with the return air space, and the plurality of exhaust valves are respectively installed outside the plurality of assembly pipes.

[0010] Preferably, a second telescopic motor is installed at a middle position of the outer surface of the expansion section, and the top surface of the fixed cylinder is installed at the output end of the second telescopic motor.

[0011] Preferably, the shapes of the plurality of cone seats and cone cylinders are all frustum-shaped, with their small ends facing downwards, and the sizes of the two are adapted.

[0012] Preferably, a plurality of first ring tubes in upper and lower arrays are installed below the outside of the reaction section, a first connecting tube and a second connecting tube are installed outside the topmost and bottommost first ring tubes respectively, the inlet valve and the outlet valve are installed outside the second connecting tube and the first connecting tube respectively, and a plurality of connecting tubes in a circumferential array are installed outside the inner sides of the plurality of first ring tubes, and the two are connected to each other, forming a heat exchange component.

[0013] Preferably, a second annular tube is installed at a middle position outside the intake tail section, a third connecting tube is installed outside the second annular tube, a second intake valve is installed at the outer end of the third connecting tube, a plurality of fixed tubes are installed outside the inner side of the second annular tube, and the two are connected, a plurality of mounting holes in an axial array are provided outside the plurality of fixed tubes, and a plurality of one-way valves are respectively installed in the plurality of mounting holes.

[0014] Preferably, one end of the air intake pipe extends into the air intake tail section, and the height thereof is not lower than the height of the fixed pipe.

[0015] Preferably, flange plates are installed at the outer ends of the expansion section, reaction section and air intake tail section, and through holes are opened on the flange plates.

[0016] (III) Beneficial effects

[0017] Compared with the prior art, the present invention provides a fluidized bed reactor for propane dehydrogenation with precise control function, which has the following beneficial effects:

[0018] 1. The fluidized bed reactor for propane dehydrogenation with precise control function is divided into an expansion section, a reaction section and an air intake tail section from top to bottom. The three sections are connected by a flange structure to form a straight cylinder. A distribution plate is installed in the reaction section. A gas collecting cone that can reciprocate up and down is installed in the reaction section, so that the gas can be discharged from the gas collecting cone after the reaction. By adjusting the up and down position of the gas collecting cone, the internal space of the reaction section can be changed, so that a certain fluid pressure is generated between the reaction section and the reactants, thereby realizing the function of controlling the reaction process.

[0019] 2. The fluidized bed reactor for propane dehydrogenation with precise control function is provided with a plurality of first loop tubes in upper and lower arrays on the wall of the reaction section, and a plurality of connecting tubes in a circumferential array are provided between the plurality of first loop tubes, so that gas or liquid can circulate between the plurality of first loop tubes and the connecting tubes to play a role of heat conduction, and the plurality of connecting tubes are evenly distributed to ensure uniform temperature conduction in the reaction section.

[0020] 3. The fluidized bed reactor for propane dehydrogenation with precise control function has a closing plate installed inside the expansion section, and a plurality of vertically arranged cone seats below it. A plurality of cones in a circular array are installed at the edge below the air collecting cone, and the plurality of cone seats are respectively inserted into the plurality of cones. The air collecting cone can be separated by the up and down movement, so that the material can flow out from the gap between the two, thereby realizing the feeding function and making it convenient for the staff to control it.

[0021] A plurality of exhaust valves are installed on the outside of the expansion section, and a plurality of evenly arrayed air outlets are opened on the outside of the air collecting cone. The exhausted gas will enter the space above the closing plate and then be discharged from the exhaust valve.

[0022] 4. The fluidized bed reactor for propane dehydrogenation with precise control function has an air inlet pipe installed at the middle position inside the air inlet tail section, on which a first air inlet valve is installed, from which air can be blown into the fluidized bed reactor, and a plurality of fixed pipes in a circumferential array are installed inside the air inlet tail section, on which a plurality of one-way valves in a uniform array are installed. During use, the staff can choose to intake air from the air inlet pipe or the fixed pipe according to the use needs, wherein the air inlet pipe intakes air from a single position in the middle, and a plurality of fixed pipes intake air from all sides at the same time, the air inlet positions are diverse, and the control is precise, which greatly improves the practicability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 For the present invention Figure 1 A schematic cross-sectional structure diagram of ;

[0025] Figure 3 It is a schematic diagram of the overall structure of the enlarged section in the present invention;

[0026] Figure 4 It is a schematic diagram of the internal structure of the enlarged section in the present invention;

[0027] Figure 5 It is a schematic diagram of the overall structure of the reaction section in the present invention;

[0028] Figure 6 Schematic diagram of the internal structure of the reaction section in the present invention;

[0029] Figure 7 It is a schematic diagram of the overall structure of the air intake tail section in the present invention;

[0030] Figure 8 Schematic diagram of the internal structure of the air intake tail section in the present invention;

[0031] Fig. 9 It is a schematic diagram of the overall structure of the air collecting cone in the present invention;

[0032] Fig.10 It is a schematic diagram of the internal structure of the air collecting cone in the present invention.

[0033] In the figure: 1-expansion section, 2-reaction section, 3-intake tail section, 4-second telescopic motor, 5-exhaust valve, 6-discharge valve, 7-entry valve, 8-second intake valve, 9-first intake valve, 10-distribution plate, 11-air collection cone, 12-assembly pipe, 13-cone seat, 14-first telescopic motor, 15-closing plate, 16-flange plate, 17-first annular pipe, 18-second connecting pipe, 19-first connecting pipe, 20-connecting pipe, 21-second annular pipe, 22-third connecting pipe, 23-intake pipe, 24-fixed pipe, 25-mounting hole, 26-cone, 27-fixed cylinder, 28-air outlet, 29-feed pipe, 30-check valve. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figure 1-10 A fluidized bed reactor for propane dehydrogenation with precise control function comprises an expansion section 1, a reaction section 2 and an air intake tail section 3, which form a straight cylindrical reactor from top to bottom. A closing plate 15 is installed above the inside of the expansion section 1, and a return air space is formed above it. A plurality of exhaust valves 5 in a circumferential array are installed outside the expansion section 1, which are communicated with the return air space. A feed pipe 29 is installed below one side of the outside of the expansion section 1, which is located below the return air space. A plurality of first telescopic motors 14 in a circumferential array are installed on the bottom surface of the closing plate 15, and a cone seat 13 is installed at the output end thereof. An air collecting cone 11 capable of reciprocating up and down is installed above the inside of the reaction section 2, with its large mouth facing downward, and a fixed cylinder 27 is installed outside the tip, and a fixed cylinder 27 is opened above the outside of the fixed cylinder 27. A plurality of air outlets 28 and a fixed cylinder 27 penetrate the closing plate 15, and the two are slidably matched, and the plurality of air outlets 28 are all located in the return air space, and a plurality of circular arrays of cone cylinders 26 are installed at the edge below the air collecting cone 11, and their positions are respectively adapted to the positions of the plurality of cone seats 13, and a heat exchange component is installed below the interior of the reaction section 2, and an inlet valve 7 and an outlet valve 6 are respectively installed outside the heat exchange component, and a distribution plate 10 is installed at the bottom of the interior of the reaction section 2, and an air intake pipe 23 is installed at the midline inside the air intake tail section 3, and a first air intake valve 9 is installed at the outer end thereof, and a plurality of circular arrays of fixed pipes 24 are installed on the side wall inside the air intake tail section 3, and a plurality of uniformly arrayed one-way valves 30 are installed outside the plurality of fixed pipes 24, and the air outlet direction thereof is toward the distribution plate 10.

[0036] As an optional technical solution of the present invention:

[0037] A plurality of assembly pipes 12 in a circular array are installed above the outer surface of the expansion section 1, which are connected to the return air space. A plurality of exhaust valves 5 are respectively installed outside the plurality of assembly pipes 12. When installing the exhaust valves 5, it is necessary to ensure good sealing between them and the installation positions so that no leakage occurs between the installation positions.

[0038] As an optional technical solution of the present invention:

[0039] A second telescopic motor 4 is installed at the middle position of the outer surface of the expansion section 1, and the top surface of the fixed cylinder 27 is installed at the output end of the second telescopic motor 4. Driven by the second telescopic motor 4, the air collecting cone 11 can achieve up and down reciprocating motion.

[0040] As an optional technical solution of the present invention:

[0041] The shapes of the multiple cone seats 13 and the cone cylinder 26 are all frustum-shaped, with their small ends facing downward, and the sizes of the two are adapted. When the cone seat 13 is inserted into the cone cylinder 26, the cone cylinder 26 can be closed to prevent the raw materials from leaking out. When the cone seat 13 is pulled out, the raw materials can slide out of the cone cylinder 26, making it convenient to evenly feed the reaction section 2.

[0042] As an optional technical solution of the present invention:

[0043] A plurality of first annular tubes 17 in an upper and lower array are installed below the outside of the reaction section 2, a first connecting tube 19 and a second connecting tube 18 are installed outside the topmost and bottommost first annular tubes 17, respectively, the inlet valve 7 and the outlet valve 6 are installed outside the second connecting tube 18 and the first connecting tube 19, respectively, a plurality of connecting tubes 20 in a circumferential array are installed outside the inner sides of the plurality of first annular tubes 17, and the two are interconnected, forming a heat exchange component, and the heat exchange medium flows through the plurality of first annular tubes 17 in sequence from bottom to top, and when the connecting tube 20 contacts the raw material, heat exchange can be achieved, thereby adjusting the temperature in the reaction section 2.

[0044] As an optional technical solution of the present invention:

[0045] A second annular tube 21 is installed at the middle position of the outside of the intake tail section 3, and a third connecting tube 22 is installed on the outside of the second annular tube 21. A second intake valve 8 is installed on the outer end of the third connecting tube 22. Multiple fixed tubes 24 are installed on the outside of the inner side of the second annular tube 21, and the two are connected. Multiple mounting holes 25 are arranged in an axial array on the outside of the multiple fixed tubes 24, and multiple one-way valves 30 are respectively installed in the multiple mounting holes 25. Multiple fixed tubes 24 in a circumferential array can achieve the effect of circumferentially uniform gas outlet, so that the material on the distribution plate 10 can react with the gas evenly.

[0046] As an optional technical solution of the present invention:

[0047] One end of the air intake pipe 23 extends into the air intake tail section 3 , and the height thereof is not lower than the height of the fixed pipe 24 , so as to avoid position interference between the components and affect the use of the components.

[0048] As an optional technical solution of the present invention:

[0049] The outer ends of the expansion section 1, the reaction section 2 and the intake tail section 3 are all installed with flange plates 16, and through holes are opened on the flange plates 16. Fasteners are used to pass through the through holes to assemble the three components together, which is convenient for installation and disassembly. In order to improve the sealing effect, seals can be installed between each flange plate 16.

[0050] The electrical components mentioned in this article are all connected to an external main controller and 220V mains electricity, and the main controller can be a conventional known device for controlling a computer or the like.

[0051] When in use, raw materials are fed into the equipment from the feed pipe 29, and the raw materials fall into the reaction section 2 from the cone 26 and are distributed on the distribution plate 10. Thereafter, the cone seat 13 closes the cone 26, and the upper and lower positions of the air collecting cone 11 are adjusted according to actual conditions to change the size of the reaction space in the reaction section 2. The staff can control the opening and closing of the first air inlet valve 9 and the second air inlet valve 8 to inflate the reaction section 2 in different ways. The heat exchange component maintains the internal temperature of the reaction section 2. The gas after the reaction enters from the air collecting cone 11, enters the return air space in turn, and is finally discharged from the exhaust valve 5. Among them, a recovery device can be installed in the return air space to recover the catalyst used for the reaction.

[0052] In summary, the features, assembly methods, use processes and functions of the various components of the fluidized bed reactor for propane dehydrogenation with precise control function are as follows: from top to bottom, it is divided into an expansion section 1, a reaction section 2 and an air intake tail section 3, and the three are connected by a flange structure to form a straight cylinder. A distribution plate 10 is installed in the reaction section 2, and a gas collection cone 11 that can reciprocate up and down is installed in the reaction section 2, so that the gas after the reaction can be discharged from the gas collection cone 11. By adjusting the up and down position of the gas collection cone 11, the internal space of the reaction section 2 can be changed to make it consistent with the reaction section 2. A certain fluid pressure is generated between the reactants, which realizes the function of controlling the reaction process. A plurality of first annular tubes 17 in an upper and lower array are installed on the wall of the reaction section 2, and a plurality of connecting tubes 20 in a circumferential array are installed between the plurality of first annular tubes 17, so that gas or liquid can circulate between the plurality of first annular tubes 17 and the connecting tubes 20, which plays a role of heat conduction, and the plurality of connecting tubes 20 are evenly distributed, which can ensure that the temperature in the reaction section 2 is evenly conducted. A closing plate 15 is installed inside the expansion section 1, and a plurality of vertically arranged cone seats 13 are arranged below the closing plate 15. A plurality of circular array cones 26 are installed at the edge below the gas cone 11, and a plurality of cone seats 13 are respectively inserted into the plurality of cones 26. The two can be separated by the up and down movement of the gas collecting cone 11, so that the material can flow out from the gap between the two, realizing the function of feeding, and the staff can conveniently control it. A plurality of exhaust valves 5 are installed on the outside of the expansion section 1, and a plurality of uniform array of gas outlets 28 are opened on the outside of the gas collecting cone 11. The exhausted gas will enter the space above the closing plate 15, and then be discharged from the exhaust valve 5. The inside of the intake tail section 3 An air inlet pipe 23 is installed in the middle position, on which a first air inlet valve 9 is installed, from which air can be blown into the fluidized bed reactor, and a plurality of fixed pipes 24 in a circumferential array are installed inside the air inlet tail section 3, on which a plurality of one-way valves 30 in a uniform array are installed. During use, the staff can choose to intake air from the air inlet pipe 23 or the fixed pipe 24 according to the use needs, wherein the air inlet pipe 23 intakes air from a single position in the middle, and the plurality of fixed pipes 24 intake air from all sides at the same time, the air inlet positions are diverse, and the control is precise, which greatly improves the practicability of the equipment.

[0053] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A fluidized bed reactor for propane dehydrogenation with precise control function, characterized in that: The invention comprises an expansion section (1), a reaction section (2) and an air intake tail section (3), which form a straight cylindrical reactor from top to bottom. A closing plate (15) is installed above the inside of the expansion section (1), and a return air space is formed above the closing plate. A plurality of exhaust valves (5) in a circumferential array are installed outside the expansion section (1), which are communicated with the return air space. A feed pipe (29) is installed below one side of the outside of the expansion section (1), which is located below the return air space. A plurality of first telescopic motors (14) in a circumferential array are installed on the bottom surface of the closing plate (15), and a cone seat (13) is installed at the output end. A gas collecting cone (11) capable of reciprocating up and down is installed above the inside of the reaction section (2), with its large mouth facing downward and a fixed cylinder (27) installed outside the tip. A plurality of air outlets (28) are opened above the outside of the fixed cylinder (27). The sealing plate (15) penetrates through the sealing plate (15), and the two are slidably matched. The plurality of air outlets (28) are all located in the return air space. The edges below the air collecting cone (11) are all equipped with a plurality of cones (26) in a circumferential array, and their positions are respectively matched with the positions of the plurality of cone seats (13). A heat exchange component is installed below the interior of the reaction section (2), and an inlet valve (7) and an outlet valve (6) are respectively installed outside the heat exchange component. A distribution plate (10) is installed at the bottom of the interior of the reaction section (2). An air intake pipe (23) is installed at the center line of the interior of the air intake tail section (3), and a first air intake valve (9) is installed at the outer end thereof. A plurality of fixed pipes (24) in a circumferential array are installed on the side wall inside the air intake tail section (3), and a plurality of uniformly arrayed one-way valves (30) are installed outside the plurality of fixed pipes (24), and their air outlet directions are toward the distribution plate (10).

2. A fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: A plurality of assembly pipes (12) in a circular array are installed above the outer surface of the expansion section (1), which are communicated with the return air space, and a plurality of exhaust valves (5) are respectively installed outside the plurality of assembly pipes (12).

3. The fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: A second telescopic motor (4) is installed at the middle position of the outer surface of the expansion section (1), and the top surface of the fixed cylinder (27) is installed at the output end of the second telescopic motor (4).

4. The fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: The shapes of the plurality of cone seats (13) and cone cylinders (26) are all frustum-shaped, with their small ends facing downwards, and the sizes of the two are adapted.

5. The fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: A plurality of first annular tubes (17) in an upper and lower array are installed below the outside of the reaction section (2); a first connecting tube (19) and a second connecting tube (18) are installed outside the top and bottom first annular tubes (17), respectively; the inlet valve (7) and the outlet valve (6) are installed outside the second connecting tube (18) and the first connecting tube (19), respectively; a plurality of connecting tubes (20) in a circumferential array are installed outside the inner sides of the plurality of first annular tubes (17), and the two are connected to each other, and the two constitute a heat exchange component.

6. The fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: A second annular tube (21) is installed at a middle position outside the intake tail section (3), and a third connecting tube (22) is installed outside the second annular tube (21). A second intake valve (8) is installed at the outer end of the third connecting tube (22). The plurality of fixed tubes (24) are installed outside the inner side of the second annular tube (21), and the two are connected. The plurality of fixed tubes (24) are provided with a plurality of mounting holes (25) arranged in an axial direction on the outside, and the plurality of one-way valves (30) are respectively installed in the plurality of mounting holes (25).

7. The fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: One end of the air intake pipe (23) extends into the air intake tail section (3), and its height is not lower than that of the fixed pipe (24).

8. The fluidized bed reactor for propane dehydrogenation with precise control function according to claim 1, characterized in that: The outer ends of the expansion section (1), the reaction section (2) and the air intake tail section (3) are all installed with flange plates (16), and the flange plates (16) are all provided with through holes.

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