A dense phase conveying device and method for powder catalysts

Abstract

The application discloses a dense phase conveying device and method for powder catalyst, wherein the dense phase conveying device comprises a conveying pipe and a gas guide pipe, the conveying pipe is arranged between a reactor and a regeneration system in communication, the gas guide pipe is arranged in the conveying pipe, at least one air suction part for air bubbles to enter the gas guide pipe is arranged on the gas guide pipe, and a gas feeding part for feeding gas into the gas guide pipe is arranged in the middle of the gas guide pipe. During the flowing of the powder catalyst in the reactor through the conveying pipe towards the regeneration system, small air bubbles are formed in the conveying pipe and enter the gas guide pipe under the action of the pressure difference between the inside and outside of the gas guide pipe, and are discharged into the reactor under the guidance of the gas guide pipe, so that the small air bubbles cannot form large air bubbles to affect the flowing of the powder catalyst, the powder catalyst can flow into the regeneration system along the conveying pipe smoothly, and the problems of fluctuation, bridging and equipment vibration in the powder dense phase conveying process are solved.

Description

Technical Field

[0001] This application relates to the field of gas-solid fluidization technology, and in particular to a dense phase conveying device and method for powder catalysts. Background Technology

[0002] Fluidization is a process that transforms particulate solids into a fluid-like state through contact with a gas or liquid. The technology that accomplishes a certain process by means of solid fluidization is called fluidization technology.

[0003] The reaction-regeneration system of a catalytic cracking / catalytic pyrolysis unit is a typical generalized circulating fluidized bed system. The main equipment includes a reactor, a regeneration system, and inclined or vertical pipes to ensure continuous catalyst circulation. This involves bubbling bed fluidization, turbulent bed fluidization, fast bed fluidization, dense phase transport, and dilute phase transport. The continuous and stable flow of solid powder catalyst between the two reactors is crucial for the operation of the reaction-regeneration system, and dense phase transport is one of the widely used transport methods.

[0004] The quality of catalyst delivery is closely related to the physical properties of the catalyst, its flow rate, the structure of the delivery line, and its condition before entering the riser. Riser delivery, in particular, is prone to problems such as noise, equipment vibration, and unstable catalyst delivery, affecting reaction and regeneration efficiency, and potentially leading to equipment damage or even safety accidents. A common cause of unstable dense-phase delivery in the riser is an excessive amount of gas (vapor) carried by the catalyst. During delivery, the catalyst flows downwards, and the gas released during this flow forms small bubbles. These small bubbles are subject to buoyancy, slowing their downward velocity and increasing their residence time, eventually accumulating into large bubbles. When these bubbles become large enough, they move upwards, potentially blocking the catalyst flow area, leading to fluidization instability or catalyst bridging. When these large bubbles rise to the riser inlet and detach, or when they burst or move vertically, a large amount of catalyst surges downwards into the space previously occupied by the bubbles, causing noise, severe equipment vibration, and fluctuations in catalyst delivery. In continuous catalyst circulation delivery, the continuous periodic formation, movement, and bursting of large bubbles in the riser cause continuous periodic fluctuations in the riser's flow rate.

[0005] The problem of dense phase transport in gas-solid risers exists in other circulating fluidized bed units similar to catalytic cracking units, such as MTO units and MTA units. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this application provides a dense phase conveying device and method for powder catalysts, thereby solving the problem of bubble aggregation affecting conveying during catalyst movement in existing technologies.

[0007] The above-mentioned objectives of the present invention are mainly achieved through the following technical solutions:

[0008] A dense-phase conveying device for powder catalysts, comprising:

[0009] A delivery pipe, used to connect the reactor and the regeneration system, and to provide space for the catalyst to flow;

[0010] A gas guide tube is provided inside the delivery pipe. The gas guide tube is provided with at least one air intake section for air bubbles to enter the gas guide tube, and an air filling section for introducing gas into the gas guide tube.

[0011] Furthermore, one end of the gas filling unit extends into the gas guide pipe, and the other end passes through the delivery pipe and extends to the outside of the delivery pipe.

[0012] Furthermore, the gas guide pipe is provided with multiple inclined baffles, which are respectively disposed above the gas supply section and the gas intake section to prevent the catalyst in the gas guide pipe from depositing and blocking the gas supply section and the gas intake section.

[0013] Furthermore, a support plate for fixing the air guide pipe is provided on the inner wall of the delivery pipe.

[0014] Furthermore, the end of the gas guide pipe away from the delivery pipe extends into the reactor and is higher than the highest material level in the reactor.

[0015] Furthermore, a valve is provided between the air guide pipe and the regeneration system.

[0016] Furthermore, the air guide tube is provided in multiple sections, and two adjacent sections of the air guide tube are connected by a socket structure, and each section of the air guide tube is provided with an air filling part.

[0017] Furthermore, the length extension direction of the air guide tube is the same as the length extension direction of the delivery tube.

[0018] Based on the same inventive concept, this application also provides a dense-phase transport method for powder catalysts, employing the aforementioned dense-phase transport device, comprising the following steps:

[0019] S1. Continuously introduce gas into the gas filling section;

[0020] S2. The powdered catalyst inside the reactor flows toward the regeneration system through a delivery pipe;

[0021] S3. As the density inside the gas delivery pipe is less than the density outside the gas delivery pipe, small bubbles are formed inside the delivery pipe and enter the gas delivery pipe under the action of the pressure difference between the inside and outside of the gas delivery pipe, and are discharged into the reactor under the guidance of the gas delivery pipe.

[0022] Furthermore, the gas is a gas that does not react with the catalyst and does not cause the catalyst to clump.

[0023] Compared with the prior art, the advantages of the present invention are as follows:

[0024] The dense phase conveying device of this invention comprises a conveying pipe and a gas guide pipe. The conveying pipe is connected between the reactor and the regeneration system, and the gas guide pipe is located inside the conveying pipe. The gas guide pipe has at least one suction section for bubbles to enter the gas guide pipe, and a gas filling section in the middle of the gas guide pipe for introducing gas into the gas guide pipe. During the dense phase conveying operation, gas is first continuously introduced into the gas filling section. As the powdered catalyst in the reactor flows towards the regeneration system through the conveying pipe, some gas is released from the dense phase of the catalyst and forms small bubbles. As the density inside the gas guide pipe is less than the density outside the gas guide pipe, the small bubbles formed inside the conveying pipe enter the gas guide pipe under the action of the pressure difference between the inside and outside of the gas guide pipe, and are discharged into the reactor under the guidance of the gas guide pipe. This prevents the small bubbles from forming large bubbles that would affect the flow of the powdered catalyst, allowing the powdered catalyst to flow smoothly along the conveying pipe into the regeneration system, thus completing the dense phase conveying of the powdered catalyst. This solves the problems of fluctuation, bridging, and equipment vibration that easily occur during the dense phase conveying of powdered catalyst. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the dense phase conveying device provided in the embodiments of this application;

[0027] Figure 2 Provided for the embodiments of this application Figure 1 A magnified view of a portion of point A in the middle;

[0028] In the diagram: 1. Delivery pipe; 2. Gas guide pipe; 21. Gas intake section; 22. Gas supply section; 23. Inclined baffle; 24. Support plate; 25. Valve; 26. Socket structure; 3. Reactor; 4. Regeneration system; 5. Catalyst. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the description of these embodiments is intended to aid in understanding the invention, but does not constitute a limitation thereof. The specific structural and functional details disclosed herein are merely for describing exemplary embodiments of the invention. However, the invention can be embodied in many alternative forms and should not be construed as being limited to the embodiments described herein.

[0030] like Figure 1-2 As shown, a dense-phase conveying device for powder catalysts includes a conveying pipe 1 and a gas guide pipe 2, wherein:

[0031] The delivery pipe 1 is used to connect the reactor 3 and the regeneration system 4, and provides flow space for the catalyst 5;

[0032] It is worth noting that the flow direction of the powdered catalyst 5 in the conveying pipe 1 can be from reactor 3 to regeneration system 4 or from regeneration system 4 to reactor 3. The positions of reactor 3 and regeneration system 4 can be interchanged according to actual requirements. For ease of explanation, reactor 3 is set above regeneration system 4, that is, the catalyst 5 in reactor 3 flows into regeneration system 4 through conveying pipe 1.

[0033] The air guide pipe 2 is located inside the delivery pipe 1. The air guide pipe 2 is provided with at least one air intake part 21 for introducing air bubbles into the air guide pipe 2. The air guide pipe 2 is provided with an air filling part 22 for introducing gas into the air guide pipe 2. The air filling part 22 can be located in the middle or lower part of the air guide pipe 2.

[0034] The air intake 21 can be a side opening directly on the air duct 2, or it can be a section of pipe connected to the inside of the air duct 2.

[0035] When the suction section 21 is configured as a pipe, the suction section 21 is inclined and one end of the suction section 21 connected to the air guide pipe 2 is higher than the other end, so as to avoid the powder catalyst 5 in the conveying pipe 1 being directly deposited in the suction section 21, thereby avoiding the suction section 21 being blocked and affecting the entry of bubbles into the air guide pipe 2.

[0036] The two ends of the air delivery tube 2 are at different heights to facilitate the movement of air bubbles within the air delivery tube 2.

[0037] The air intake section 21 on the air delivery tube 2 is used to transport air bubbles from the tube 1 into the air delivery tube 2.

[0038] When air is introduced into the air pipe 2 through the air filling section 22, the outside of the air pipe 2 is a mixture of air and powdered catalyst 5, while the inside of the air pipe 2 is the introduced air. This causes the density inside the air pipe 2 to be lower than the density outside the air pipe 2. The density inside the air pipe 2 is lower than the density of the dense phase of catalyst 5 outside the air pipe 2, thus forming a pressure difference between the inside and outside of the air pipe 2. Under the action of the pressure difference, the small bubbles formed in the delivery pipe 1 enter the air pipe 2 from the outside of the air pipe 2 through the air intake section 21, so as to prevent the bubbles from accumulating in the delivery pipe 1.

[0039] When performing the dense phase conveying method for powder catalyst 5, the above-mentioned dense phase conveying device is used, including the following steps:

[0040] S1. Continuously introduce gas into the gas filling section 22;

[0041] S2. The powdered catalyst 5 in reactor 3 flows toward regeneration system 4 through conveying pipe 1;

[0042] S3. As the density inside the gas delivery pipe 2 is less than the density outside the gas delivery pipe 2, small bubbles formed inside the delivery pipe 1 enter the gas delivery pipe 2 under the action of the pressure difference between the inside and outside of the gas delivery pipe 2, and are discharged into the reactor 3 under the guidance of the gas delivery pipe 2.

[0043] The working principle of this embodiment is as follows: A conveying pipe 1 and a gas guide pipe 2 are connected. The conveying pipe 1 is positioned between the reactor 3 and the regeneration system 4. The gas guide pipe 2 is located inside the conveying pipe 1 and has at least one suction section 21 for air bubbles to enter it. A gas filling section 22 for introducing gas into the gas guide pipe 2 is located in the middle of the gas guide pipe 2. During the dense phase conveying method operation, gas is continuously introduced into the gas filling section 22. As the powdered catalyst 5 in the reactor 3 flows towards the regeneration system 4 through the conveying pipe 1, some of the gas... Catalyst 5 is released from the dense phase and forms small bubbles. As the density inside the gas guide pipe 2 is less than the density outside the gas guide pipe 2, the small bubbles formed in the conveying pipe 1 enter the gas guide pipe 2 under the action of the pressure difference between the inside and outside of the gas guide pipe 2, and are discharged into the reactor 3 under the guidance of the gas guide pipe 2. This prevents the small bubbles from forming large bubbles and affecting the flow of powdered catalyst 5. The powdered catalyst 5 can then flow smoothly along the conveying pipe 1 into the regeneration system 4, completing the dense phase conveying of powdered catalyst 5. This solves the problems of fluctuation, bridging and equipment vibration that are prone to occur during the dense phase conveying of powdered catalyst.

[0044] It is worth explaining in detail that the operation of continuously introducing gas into the gas filling section 22 is carried out before the powdered catalyst 5 in the reactor 3 flows toward the regeneration system 4 through the conveying pipe 1, so that the gas can move more stably in the gas guide pipe 2, and the end of the gas guide pipe 2 away from the reactor 3 can be set to a closed state, thereby constraining the gas to move more stably toward the reactor 3.

[0045] Furthermore, based on the above embodiments, one end of the gas filling unit 22 extends into the gas guide pipe 2, and the other end passes through the delivery pipe 1 and extends to the outside of the delivery pipe 1.

[0046] The gas filling unit 22 is connected to the gas delivery pipe 2 so as to facilitate connection to the gas delivery pipe 1.

[0047] Furthermore, based on the above embodiments, the gas introduced into the gas filling section 22 is a gas that does not react with the catalyst 5 and does not cause the catalyst 5 to clump.

[0048] During the process of introducing gas into the gas filling section 22, the gas bubbles drawn into the gas guide pipe 2 from the gas intake section 21 are accompanied by some powdered catalyst 5. This restricts the gas to the characteristics of not being able to react with the catalyst 5 and not causing the catalyst 5 to clump, thus avoiding direct reaction between the gas and the catalyst 5. Under the action of the gas flow in the gas guide pipe 2, the powdered catalyst 5 enters the reactor 3 and is redeposited for re-entry into the delivery pipe 1, thus avoiding waste of the powdered catalyst 5.

[0049] Furthermore, based on the above embodiments, the gas guide pipe 2 is provided with a plurality of inclined baffles 23, which are respectively disposed above the gas filling section 22 and the gas intake section 21 to prevent the catalyst 5 in the gas guide pipe 2 from depositing and blocking the gas filling section 22 and the gas intake section 21.

[0050] The inclined baffle 23 can also be configured in different shapes. Under the guidance of the inclined baffle 23, the catalyst 5 is prevented from entering the gas filling section 22 or the gas intake section 21 during the downward deposition process. Furthermore, there is a gap between one edge of the inclined baffle 23 and the inner wall of the gas guide pipe 2 to reserve space for air flow.

[0051] Furthermore, based on the above embodiments, a support plate 24 for fixing the air guide pipe 2 is provided on the inner wall of the conveying pipe 1, which improves the stability of the air guide pipe 2 installed in the conveying pipe 1, and the air guide pipe 2 can be inserted into the support plate 24 to facilitate the disassembly, assembly and replacement of the air guide pipe 2.

[0052] Furthermore, based on the above embodiments, the end of the gas guide pipe 2 away from the conveying pipe 1 extends into the reactor 3 and is higher than the highest material level in the reactor 3. When part of the powder catalyst 5 is blown into the reactor 3, the air mixed with catalyst 5 is prevented from disturbing the powder catalyst 5 flowing into the conveying pipe 1.

[0053] Furthermore, based on the above embodiments, a valve 25 is provided between the gas guide pipe 2 and the regeneration system 4. The amount of powder catalyst 5 is controlled by operating the valve 25. The valve 25 can be an automatically controlled electronic valve 25 or a manually controlled mechanical valve 25.

[0054] Furthermore, based on the above embodiments, the air guide pipe 2 is provided with multiple sections, and two adjacent sections of the air guide pipe 2 are connected by a socket structure 26, and each section of the air guide pipe 2 is provided with an air filling part 22.

[0055] The multi-segment air guide tube 2 can be assembled and used in accordance with the needs of the delivery tube 1. The bottom position of the air guide tube 2 is controlled in the middle of the delivery tube 1. Combined with the multi-segment air guide tube 2 and the multiple air intake parts 21 and air filling parts 22 on the multi-segment air guide tube 2, the bubble discharge effect is improved.

[0056] The insertion mechanism includes a matching large end and a small end. The small end can be inserted into the large end to form a connection between two adjacent air tubes 2. That is, the two ends of each air tube 2 are respectively set as a large end and a small end.

[0057] The length extension direction of the air guide tube 2 can be the same as that of the delivery tube 1, so that after the bubbles enter the air guide tube 2, they can move smoothly in the air guide tube 2 and avoid the bubbles from accumulating in the air guide tube 2.

[0058] It should be understood that the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Although the terms "first," "second," etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit, without departing from the scope of the exemplary embodiments of the invention.

[0059] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" in this article describes another relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the related objects before and after it are in an "or" relationship.

[0060] It should be understood that in the description of this invention, the terms "upper," "vertical," "inner," "outer," etc., indicate the orientation or positional relationship as commonly placed when the disclosed product is used, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0061] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0062] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” “containing,” and / or “including” as used herein specify the presence of the stated features, integers, steps, operations, units, and / or components, and do not exclude the presence or addition of one or more other features, quantities, steps, operations, units, components, and / or combinations thereof.

[0063] Specific details are provided in the following description to provide a complete understanding of the exemplary embodiments. However, those skilled in the art will understand that the exemplary embodiments can be implemented without these specific details. In other embodiments, well-known processes, structures, and techniques may be omitted in the depiction of non-essential details to avoid obscuring the exemplary embodiments.

[0064] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A dense phase conveying apparatus for powder catalyst, characterized by, It comprises: a conveying pipe for connecting the reactor and the regeneration system and providing a flow-through space for the catalyst; a gas guide pipe arranged in the conveying pipe, the gas guide pipe being provided with at least one gas suction part for introducing gas bubbles into the gas guide pipe, and the gas guide pipe being provided with a gas feeding part for feeding gas into the gas guide pipe.

2. The apparatus for dense phase conveying of a powder catalyst according to claim 1, wherein: One end of the gas feeding part extends into the gas guide pipe, and the other end of the gas feeding part extends through the conveying pipe and is outside the conveying pipe.

3. The dense-phase conveying device for powder catalysts as described in claim 1, characterized in that: A plurality of inclined baffles are arranged in the gas guide pipe, and the inclined baffles are arranged above the gas feeding part and the gas suction part, respectively, to prevent the catalyst in the gas guide pipe from depositing and blocking the gas feeding part and the gas suction part.

4. The apparatus according to claim 1, wherein the apparatus is characterized by: A support plate for fixing the gas guide pipe is arranged on the inner wall of the conveying pipe.

5. The apparatus according to claim 1, wherein: the powder catalyst is conveyed in a dense phase. 5 The end of the gas guide pipe away from the conveying pipe extends into the reactor and is higher than the highest material level in the reactor.

6. The apparatus according to claim 1, wherein the apparatus is used for the dense phase conveying of a powder catalyst. A valve is arranged between the gas guide pipe and the regeneration system.

7. The apparatus according to claim 1, wherein: the apparatus is used for the dense phase conveying of a powder catalyst. The gas guide pipe is provided with multiple sections, and adjacent two sections of the gas guide pipe are connected through a socket structure, and the gas feeding part is arranged on each section of the gas guide pipe.

8. The apparatus according to claim 1, wherein: the apparatus is used for the dense phase conveying of a powder catalyst. The length extension direction of the gas guide pipe is the same as the length extension direction of the conveying pipe.

9. A method of dense phase conveying of a powder catalyst, characterized by The dense phase conveying device according to any one of claims 1-8 comprises the following steps: S1. continuously feeding gas into the gas feeding part; S2. the powder catalyst in the reactor flows through the conveying pipe towards the regeneration system; S3. under the action of the pressure difference between the inside and outside of the gas guide pipe, small gas bubbles in the conveying pipe enter the gas guide pipe and are discharged into the reactor under the guidance of the gas guide pipe, accompanied by the density in the gas guide pipe being less than the density outside the gas guide pipe.

10. The method of claim 9, wherein the powder catalyst is transported in a dense phase. 5 The gas is a gas that does not react with the catalyst and does not cause the catalyst to agglomerate.

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