A multi-zone reactor with a cyclone separator

Abstract

The present invention relates to the technical field of petrochemical production equipment, and specifically to a multi-zone reactor with a cyclone separator, comprising a main cylinder and a sub-cylinder arranged vertically, an annular shell is provided between the top of the main cylinder and the top of the sub-cylinder, the cyclone separator comprises a pre-vortexer arranged at a position of the annular shell close to the main cylinder and a vortex guide arranged at the inner top of the main cylinder, the vortex guide comprises a head, a jacket and a plurality of guide baffles located at the top of the main cylinder, an annular flow channel is formed between the jacket and the inner wall of the head, the guide baffles are distributed in the annular flow channel along the circumferential direction, and the guide baffles are spirally guided along the longitudinal direction. The pre-vortexer can make the fluid flowing in generate a rotating flow state around the curved central axis of the large annular shell, breaking the biased flow state caused by the centrifugal force when it flows through the annular shell. The vortex guide at the top of the main cylinder can make the fluid coming in from the pre-vortexer generate a circumferentially evenly distributed rotating flow state around the central vertical axis of the main cylinder, which plays a role in further strengthening the vortex.

Description

Technical Field

[0001] The invention relates to the technical field of petrochemical production equipment, and in particular to a multi-zone reactor with a cyclone separator. Background Art

[0002] Among the several production process technologies of polypropylene, there is a multi-zone circulation reactor that uses upper and lower connecting pipes to combine the lifting section and the settling section into an integrated multi-zone circulation reactor. During operation, the polymer particles in the reaction zone of the lifting section are entrained by the gas phase monomer provided by the fan and flow upward, and flow from bottom to top in the lifting zone of the high-speed fluidized bed. Then it enters the settling section through the upper connecting pipe. The fluid medium in the connecting pipe of the multi-zone circulation reactor is the circulating gas entrained polypropylene particles. The connecting pipe should comply with the relevant specifications and standards of pipelines and pressure vessels, and then meet the special requirements of the reactor. At the top of the settling zone, the polymer particles enter the reaction zone of the settling section after completing the gas-solid separation in the stripping zone. The polymer particles in the reaction zone of the settling section are subjected to the action of gravity to form a dense phase plunger and flow downward, and are discharged in the lower section; at the bottom of the reactor, the polymer is recycled into the reaction zone of the lifting section.

[0003] In recent years, as petrochemical plants have developed towards large-scale production, the volume of reactors has become larger and larger, and the height has become higher and higher. As the diameter of the container and the scale of production increase, the reaction process has a large amount of material flow and a fast medium flow rate, which is easy to cause vibration. According to actual production needs, the inventors designed the following Figure 1 The reactor shown has a structure including a first cylinder 01 and a second cylinder 02 arranged vertically and in parallel, a side interface is provided on the side wall of the upper end portion of the first cylinder 01, and an upper interface is provided on the upper end portion of the second cylinder 02, the side interface of the first cylinder 01 and the upper interface of the second cylinder 02 are connected via an annular shell 03, the annular shell 03 is connected to the side interface of the first cylinder 01 and then extends laterally away from the second cylinder 02, then extends upward to arch and bend, and then connects downward to the upper port of the second cylinder 02.

[0004] The above reactor has problems:

[0005] The upper connecting pipe is designed as a ring shell that interfaces with the first cylinder 01 from the side, which brings the following disadvantages:

[0006] 1. The eccentric connection makes the structure asymmetric, and strong support is needed to stabilize the towering structure. The single ring shell structure that meets large-scale production capacity has a larger diameter of the flow cross section, thicker wall thickness, strong rigidity, poor ability to resist vibration fatigue, and unstable structure;

[0007] 2. The eccentric asymmetric structure makes the medium of the whole device circulate in a concentrated manner, the degree of asymmetry is increased, and the vibration caused by the fast flow rate of the medium during operation is more obvious;

[0008] 3. Reactors with large production capacity require ring shells with larger diameters and thicker walls, which are difficult to process;

[0009] 4. The diameter of the ring shell of the side interface is large, the wall thickness is thick, and the rigidity is strong. During operation, the structural rigidity of the sedimentation section and its vertical stability are affected, which is not conducive to the uniform distribution of the medium;

[0010] 5. The large opening connecting the settlement area seriously weakens the strength of the cylinder, requiring the design of integral reinforcement cylinder sections and thick-walled forging pipes, which significantly increases the equipment cost;

[0011] 6. The flow rate of the gas-particle mixed medium entering the sedimentation section through a large annular shell is too large, and it is difficult to achieve a uniform state after a swirl cycle;

[0012] 7. Inconvenient for maintenance and protection.

[0013] In view of the above technical problems in the prior art, it is necessary to innovatively design a reactor to meet the above purpose requirements. Summary of the invention

[0014] In view of the above technical problems in the prior art, the present invention provides a multi-zone reactor with a cyclone separator.

[0015] To achieve the above object, the present invention provides the following technical solutions:

[0016] Provided is a multi-zone reactor with a cyclone separator, comprising a main cylinder and a sub-cylinder arranged vertically, an annular shell for medium circulation is arranged between the top of the main cylinder and the top of the sub-cylinder, a cyclone separator is arranged on the top of the main cylinder and the annular shell, the cyclone separator comprises a pre-cyclone arranged at a position of the annular shell close to the main cylinder and a cyclone guide arranged at the inner top of the main cylinder, the cyclone guide comprises a head located at the top of the main cylinder, a jacket located in the head and a plurality of guide baffles, an annular flow channel is formed between the jacket and the inner wall of the head, the guide baffles are distributed in the annular flow channel along the circumferential direction, and each guide baffle is in a spiral guide shape along the longitudinal direction.

[0017] Specifically, the pre-swirler includes a plurality of swirl plates, which form a cage-type structure, and each swirl plate is in a spiral flow-guiding shape along the axial direction of the annular shell.

[0018] Specifically, the outer side of the cage structure is closely attached to the inner wall of the annular shell, and the cage structure is a curved cage structure whose inner cavity radius gradually decreases along the direction approaching the main cylinder.

[0019] Specifically, a flange body is provided on the top of the main cylinder, a flange cover is provided at the end of the annular shell, the annular shell and the flange cover are welded together, the flange cover and the flange body are sealed and fixed, the cage structure is located in the flange body, and the inner side of the cage structure is a hollow reduced diameter structure.

[0020] Specifically, an outer cylinder is arranged on the outer side of the cage structure, the outer side of the cage structure is closely attached to the inner wall of the outer cylinder, a positioning flange is fixed to the flange body, and the positioning flange is fixedly connected to the outer cylinder.

[0021] Specifically, the swirl plate is in the shape of a single-curved sheet; or the swirl plate is in the shape of a hyperbolic spiral groove with a U-shaped cross section.

[0022] Specifically, a plurality of support plates are provided at the port of the head, the plurality of support plates are distributed along the circumferential direction, the support plates are arranged obliquely relative to the center line of the main cylinder, and the support plates and the jacket are fixed to each other.

[0023] Specifically, the support plate is a flat plate or an arc-shaped plate, one side of the support plate is in close contact with the inner wall of the main cylinder and are welded and fixed to each other, and the other side of the support plate is in close contact with the inner wall of the head and are welded and fixed to each other.

[0024] Specifically, a plurality of internal leakage holes are opened on the lower side wall of the jacket.

[0025] Specifically, the gap between the jacket and the head is consistent from top to bottom; or the gap between the jacket and the head gradually decreases from top to bottom.

[0026] Beneficial effects of the present invention:

[0027] The multi-zone reactor with a cyclone separator of the present invention has the following effects:

[0028] (1) Symmetrical connection structure optimizes stress:

[0029] The medium circulation annular shell connecting the top of the main cylinder and the auxiliary cylinder is improved to be connected to the top of the main cylinder. Compared with the original side opening connection structure of the cylinder, the connection structure is more symmetrical and balanced in force, avoiding the problems caused by the tangential openings between the annular shell and the sedimentation section. In particular, maintaining the structural rigidity of the main cylinder and the auxiliary cylinder and their vertical stability is the key to ensuring the axially symmetrical and uniform distribution of the gas-solid two-phase flow medium in the reactor.

[0030] The symmetrical structure does not require strong support to make the towering structure stable. The single ring shell structure that meets large-scale production capacity has strong rigidity, strong ability to resist vibration fatigue, and stable structure. The symmetrical structure allows the medium of the entire device to circulate evenly, the degree of symmetry is improved, and the medium flow rate is fast during operation without causing obvious vibration. The reactor with large production capacity does not need a ring shell with a larger diameter and thicker wall, and the ring shell is easy to process.

[0031] (2) Lightweight design of the top of the main cylinder:

[0032] The special-shaped large openings connecting the main cylinder are eliminated, which avoids serious weakening of the cylinder's strength. It is no longer necessary to design integral reinforcement cylinder sections and thick-walled forging pipes, which reduces the weight of the equipment. It is also unnecessary to do the blanking layout, groove processing, welding, post-weld heat treatment, hot processing deformation treatment, and weld seal non-destructive testing of special-shaped openings, which reduces equipment costs and shortens processing cycles.

[0033] Further:

[0034] (3) A triple cyclone and flow guide structure is set up to achieve efficient gas-solid separation:

[0035] The first rotational flow pattern generated by flowing through the pre-rotator, the second rotational flow pattern generated by flowing through the jacket guide baffle, and the third rotational flow pattern generated by flowing through the support plate can make the gas-solid mixed fluid medium evenly distributed along the circumference of the main cylinder, and completely realize the efficient separation of gas and solid. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the structure of an existing reactor.

[0037] Figure 2 Schematic diagram of the structure of a multi-zone reactor with a cyclone separator in the embodiment.

[0038] Figure 3 It is a partial cross-sectional schematic diagram of a multi-zone reactor with a cyclone separator in an embodiment.

[0039] Figure 4 Schematic diagram of a bent cage pre-cyclone of a multi-zone reactor with a cyclone separator in an embodiment.

[0040] Figure 5 Schematic diagram of a vertical cage pre-cyclone of a multi-zone reactor with a cyclone separator in an embodiment.

[0041] Figure 6 Schematic diagram of the connection between the support plate and various structures in the embodiment.

[0042] Figure 7 It is a schematic diagram of the connection between another support plate and various structures in the embodiment.

[0043] Figure 1 Reference numerals:

[0044] 01 first cylinder, 02 second cylinder, 03 annular shell;

[0045] Figure 2-7 Reference numerals:

[0046] 1 main cylinder, 2 auxiliary cylinder, 4 ring shell, 5 head, 6 jacket, 7 guide baffle, 8 pre-rotator, 81 curved cage pre-rotator, 82 straight cage pre-rotator, 83 positioning flange, 84 outer cylinder, 9 internal leakage hole, 10 flange cover, 11 bolt and nut assembly, 12 sealing gasket, 13 flange body, 14 support plate, 15 arc-shaped support plate. DETAILED DESCRIPTION

[0047] The present invention is described in detail below in conjunction with specific embodiments and drawings.

[0048] The multi-zone reactor with cyclone separator of this embodiment is as follows: Figures 2 to 4 As shown, it includes a main cylinder 1 and a sub-cylinder 2 arranged vertically, an annular shell 4 for medium circulation is arranged between the top of the main cylinder 1 and the top of the sub-cylinder 2, and a cyclone separator is arranged on the top of the main cylinder 1 and the annular shell 4. The cyclone separator includes a pre-swirl device 8 arranged at a position of the annular shell 4 close to the main cylinder 1 and a guide swirl device arranged at the inner top of the main cylinder 1. The pre-swirl device 8 includes a plurality of swirl plates, and the plurality of swirl plates form a cage structure. Each swirl plate is in a spiral flow guide shape along the axial direction of the annular shell 4, that is, the pre-swirl device 8 is a spiral blade arranged in combination on the inner wall of the annular shell 4, which can make the flowing fluid generate a rotating flow state for the first time around the curved central axis of the large annular shell 4, breaking the biased flow state caused by centrifugal force when it flows through the annular shell 4. The cage structure is a curved cage pre-swirl device 81, the outer side of which is close to the inner wall of the annular shell 4, and the cage structure is a curved cage structure with the inner cavity radius gradually decreasing along the direction close to the main cylinder 1. The pre-rotator 8 of the bending cage not only plays a pre-rotation role, but also has the function of evenly distributing the material in the circumferential direction. The bending cage structure with variable diameter is suitable for casting and can be disassembled and replaced.

[0049] The swirl guide includes a head 5 located at the top of the main cylinder 1, a jacket 6 located inside the head 5 and a plurality of guide baffles 7. An annular flow channel is formed between the jacket 6 and the inner wall of the head 5. The guide baffles 7 are distributed circumferentially in the annular flow channel. Each guide baffle 7 is in a spiral guide shape along the longitudinal direction, which can allow the fluid coming in from the pre-swirler 8 to generate a circumferentially evenly distributed rotating flow state around the central vertical axis of the main cylinder 1 for a second time, thereby further strengthening the swirl.

[0050] Combination Figure 5As shown, in another embodiment, a flange body 13 is provided at the top of the main cylinder 1, a flange cover 10 is provided at the end of the annular shell 4, the annular shell 4 and the flange cover 10 are welded and connected, the flange cover 10 and the flange body 13 are sealed and fixed by bolt and nut assemblies 11 and sealing gaskets 12, the cage structure is changed to be located inside the flange body 13, and the inner side of the cage structure is a hollow reduced diameter straight cage structure, the pre-rotator is a straight cage pre-rotator 82, the outer side of the straight cage pre-rotator 82 is provided with an outer cylinder 84, the outer side of which is tightly attached to the inner wall of the outer cylinder 84, the flange body 13 is fixed with a positioning flange 83, and the positioning flange 83 is fixedly connected to the outer cylinder 84. The straight cage pre-rotator 82 has an outer cylinder 84, which is inserted into the flange body 13 at the top of the main cylinder 1, and can be disassembled and replaced, which not only plays a pre-rotation role, but also has the function of circumferential uniform distribution.

[0051] In this embodiment, the swirl plate of the pre-swirler 8 is in the shape of a single-curved sheet; or the swirl plate is in the shape of a hyperbolic spiral groove with a U-shaped cross section.

[0052] In this embodiment, a plurality of support plates 14 are provided at the port of the head 5 for fixing and supporting the jacket 6. The plurality of support plates 14 are distributed circumferentially, and the support plates 14 form an inclination angle θ with the center line of the main cylinder 1, that is, the support plates 14 are arranged obliquely to enhance the swirl for the third time.

[0053] In this embodiment, the support plate is Figure 6 The flat plate shown or Figure 7 The arc-shaped support plate 15 shown, one side of the support plate 14 / 15 is closely attached to the inner wall of the main cylinder 1 and welded to each other, and the other side is closely attached to the inner wall of the head 5 and welded to each other.

[0054] In this embodiment, a plurality of internal leakage holes 9 are opened on the lower side wall of the jacket 6. The size and distribution of the internal leakage holes 9 depend on the reaction process and production capacity requirements, and are mainly used to facilitate the timely separation of the squeezed airflow from the mixture and the particles.

[0055] In this embodiment, the gap between the jacket 6 and the head 5 is consistent from top to bottom; or the gap between the jacket 6 and the head 5 gradually decreases from top to bottom.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A multi-zone reactor with a cyclone separator, characterized in that: It includes a main cylinder body and a sub-cylinder body arranged vertically, an annular shell for medium circulation is arranged between the top of the main cylinder body and the top of the sub-cylinder body, a cyclone separator is arranged on the top of the main cylinder body and the annular shell, the cyclone separator includes a pre-vortex device arranged at a position of the annular shell close to the main cylinder body and a vortex guide device arranged at the inner top of the main cylinder body, the vortex guide device includes a head located at the top of the main cylinder body, a jacket located in the head and a plurality of guide baffles, an annular flow channel is formed between the jacket and the inner wall of the head, the guide baffles are distributed in the annular flow channel along the circumferential direction, and each guide baffle is in a spiral guide shape along the longitudinal direction.

2. A multi-zone reactor with a cyclone separator according to claim 1, characterized in that: The pre-swirler comprises a plurality of swirl plates, which form a cage structure, and each swirl plate is in a spiral flow-guiding shape along the axial direction of the annular shell.

3. A multi-zone reactor with a cyclone separator according to claim 2, characterized in that: The outer side of the cage structure is closely attached to the inner wall of the ring shell, and the cage structure is a curved cage structure with the inner cavity radius gradually decreasing along the direction approaching the main cylinder.

4. A multi-zone reactor with a cyclone separator according to claim 2, characterized in that: A flange body is provided on the top of the cylinder, a flange cover is provided on the end of the annular shell, the annular shell and the flange cover are welded together, the flange cover and the flange body are sealed and fixed, the cage structure is located in the flange body, and the inner side of the cage structure is a hollow reduced diameter structure.

5. A multi-zone reactor with a cyclone separator according to claim 4, characterized in that: An outer cylinder is arranged on the outer side of the cage structure, the outer side of the cage structure is closely attached to the inner wall of the outer cylinder, a positioning flange is fixed on the flange body, and the positioning flange is fixedly connected with the outer cylinder.

6. The multi-zone reactor with a cyclone separator according to claim 2, characterized in that: The swirl plate is in the shape of a single-curved sheet; or the swirl plate is in the shape of a hyperbolic spiral groove with a U-shaped cross section.

7. The multi-zone reactor with a cyclone separator according to claim 1, characterized in that: A plurality of support plates are arranged at the port of the head, the plurality of support plates are distributed along the circumferential direction, the support plates are arranged obliquely relative to the center line of the main cylinder, and the support plates and the jacket are fixed to each other.

8. The multi-zone reactor with a cyclone separator according to claim 7, characterized in that: The support plate is a flat plate or an arc-shaped plate, one side of the support plate is closely attached to the inner wall of the main cylinder and are welded and fixed to each other, and the other side of the support plate is closely attached to the inner wall of the head and are welded and fixed to each other.

9. The multi-zone reactor with a cyclone separator according to claim 1, characterized in that: The lower side wall of the jacket is provided with a plurality of internal leakage holes.

10. The multi-zone reactor with a cyclone separator according to claim 1, characterized in that: The gap between the jacket and the head is consistent from top to bottom; or the gap between the jacket and the head gradually decreases from top to bottom.

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