A new structure of catalyst distributor

Abstract

A new structure of catalyst distributor mainly relates to the field of catalytic cracking technology, comprising an outer sleeve body and a spent riser, the outer sleeve body comprises coaxially distributed first sleeve body and second sleeve body, the bottom of the first sleeve body is provided with an annular top plate, the outer edge of the top plate and the top of the second sleeve body are provided with a head, the bottom of the second sleeve body is provided with a fluidization wind ring pipe, the spent riser penetrates through the first sleeve body and the head and then extends into the second sleeve body, a plurality of nozzles are arranged on the head, and the inner surfaces of the top plate, the head and the nozzles are coated with a wear-resistant layer. The catalyst distributor with the structure can make the density of the catalyst uniformly distributed in the distributor, avoid the mixing combustion of carbon monoxide and oxygen in the dense phase bed layer caused by the uneven distribution of the catalyst, and thus cause damage to the equipment of the dilution catalyst bed layer; the catalyst can also effectively resist the continuous erosion of the catalyst, reduce the wear of the distributor and other internal parts, and prolong the service life of the distributor.

Description

Technical Field

[0001] This utility model relates to the field of catalytic cracking technology, and in particular to a catalyst distributor with a novel structure. Background Technology

[0002] The fluidized bed reactor-regenerator is a crucial site for catalyst regeneration after reaction. The carbon-containing catalyst, called the "regenerated catalyst," is continuously discharged from the reaction zone. The reactivated catalyst from the regeneration zone, called the "regenerated catalyst," is recycled back to the reaction zone. The catalyst is fluidized using gaseous flow, circulating between the reaction and regeneration zones. Driven by bottom-feed air, it enters the regenerator through a catalyst distributor. Heated air at high temperatures carries the catalyst to the upper part of the dense-phase bed in the regenerator and distributes it evenly within the bed using various structures to achieve thorough catalyst regeneration. Therefore, the uniformity of the catalyst distribution directly affects the regeneration effect. Uneven catalyst distribution can lead to the mixing and combustion of carbon monoxide and oxygen in the dilute catalyst bed, resulting in lean tail combustion and a sharp rise in the lean temperature, causing significant damage to the equipment in the dilute bed.

[0003] Please see Figure 1 and Figure 2 The existing catalyst distributor structure includes an outer sleeve 2, a regenerating riser 10 extending into the outer sleeve 2, a fluidizing air ring pipe 1 located at the bottom of the outer sleeve 2, and several branch pipes 3 located at the top of the outer sleeve 2 and distributed along the circumference. The inner surfaces of the outer sleeve 2 and the branch pipes 3 are covered with a high wear-resistant lining 5. Several square outlets 4 are opened on the outer wall of the branch pipes 3. The catalyst passes through the outer sleeve and reaches the branch pipe under the action of the fluidizing air, and is sprayed out into the regenerator through the square outlets 4. The disadvantages of this structure are as follows: Under the action of the bottom fluidizing air, the catalyst continuously scours the inner surface of the distributor. When the catalyst enters the branch pipe from the high-pressure outer sleeve, it has a high flow velocity. The initial section of the branch pipe is a high-velocity zone, meaning that the amount of catalyst leaking from the square outlet near the outer sleeve is greater than that from the square outlet further away from the outer sleeve. This causes uneven catalyst distribution to some extent. In addition, when the catalyst flows too fast through the square outlet, it will scour the surrounding material legs, tie rods, etc. After a certain period of time, due to the special environment of the fluidized bed device, the inside of the distributor and other internal components are also easily scoured by this catalyst, causing significant wear. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this utility model is to propose a catalyst distributor with a novel structure.

[0005] The purpose of this utility model is achieved by the following technical solution. A novel catalyst distributor according to this utility model includes an outer sleeve and a standby riser. The outer sleeve includes a first sleeve and a second sleeve coaxially distributed. The bottom of the first sleeve is provided with an annular top plate, and a cap is provided between the outer edge of the top plate and the top of the second sleeve. The bottom of the second sleeve is provided with a fluidizing air ring pipe. The standby riser passes through the first sleeve and the cap and extends into the second sleeve. Several nozzles are provided on the cap. The inner surfaces of the top plate, the cap, and the nozzles are coated with a wear-resistant layer.

[0006] Furthermore, the generatrix of the end cap is an elliptical arc.

[0007] Furthermore, the wear-resistant layer is a cobalt-based alloy wear-resistant layer.

[0008] Furthermore, the nozzles on the end cap are arranged in a circumferential array.

[0009] Based on the aforementioned technical solution, this utility model has the following beneficial effects:

[0010] (1) When air is delivered from the bottom of the cylinder, the catalyst density distribution in the catalyst distributor of this structure is uniform, avoiding the mixing and combustion of carbon monoxide and oxygen in the dilute catalyst bed caused by uneven distribution of the catalyst, and avoiding the dilute tail combustion that causes the dilute temperature to rise sharply and damage the equipment in the dilute bed.

[0011] (2) The catalyst density in the catalyst distributor under this structure is uniformly distributed. The catalyst flow rate and content from the nozzle to the regenerator are the same, which will not scour the material around the nozzle. The top plate, end cap and inner surface of the nozzle are coated with a cobalt-based alloy wear-resistant layer, which can effectively resist the continuous scouring of the catalyst, reduce the wear on the distributor and other internal parts, and extend the service life of the distributor and nozzle.

[0012] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the existing catalyst distributor in the regenerator.

[0014] Figure 2 yes Figure 1 Top view.

[0015] Figure 3 This is a schematic diagram of a novel catalyst distributor according to this utility model.

[0016] Figure 4 This is a bottom view of the top plate and end cap in a catalyst distributor with a novel structure according to this utility model.

[0017] [Attached image labels]

[0018] 1. Fluidizing air ring pipe, 2. Outer sleeve, 201. First sleeve, 202. Second sleeve, 3. Branch pipe, 4. Square outlet, 5. High wear-resistant lining, 6. Top plate, 7. End cap, 8. Wear-resistant layer, 9. Nozzle, 10. Riser pipe. Detailed Implementation

[0019] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings:

[0020] Please see Figure 3 ,exist Figure 1 The existing catalyst distributor structure shown includes a fluidizing air ring pipe 1 located at the bottom of the outer sleeve 2 of the catalyst distributor for carrying the catalyst to the top of the distributor, and a stand-up pipe 10 extending into the inner sleeve 2. Based on the high wear-resistant lining 5 coated on the inner surface of the outer sleeve 2, the catalyst distributor of this invention divides the outer sleeve into a first cylinder 201 and a second cylinder 202 with the same outer diameter and coaxially distributed. It also includes an annular top plate 6 located at the bottom of the first cylinder 201 and a fluidizing air ring pipe 10 located at the bottom of the second cylinder. A cap is provided between the outer edge of the top plate 6 and the top of the second cylinder. The inner edge of the top plate is connected to the outer wall of the first cylinder 201, and the outer edge is connected to the top wall surface of the cap 7. In this embodiment, the generatrix of the cap 7 is an elliptical arc. The riser 10 extends into the second cylinder 202 after passing through the first cylinder 201 and the cap 7. A wear-resistant layer 8 is coated on the inner surfaces of the top plate 6 and the elliptical cap 7. In this embodiment, the wear-resistant material is a cobalt-based alloy wear-resistant layer. The bottom wall surface of the cap is connected to the outer wall of the second cylinder 202, and the cap 7 is provided with a plurality of nozzles 9 arranged in a circumferential array (e.g., Figure 4(As shown); The top plate 6 and elliptical head 7 structure arranged from top to bottom ensure that when the fluidizing air carrying the catalyst through the fluidizing air ring pipe reaches the top of the distributor, the flow velocity will be relatively reduced due to the obstruction of the top plate. At this time, the catalyst under the action of the fluidizing air is buffered to a certain extent in the chamber, reducing the flow velocity of the catalyst. It mixes with the continuously blown-up catalyst, making this area a small mixing zone with uniform catalyst density. Then, it flows out through the evenly distributed nozzles on the head, so that the flow velocity and content of the catalyst flowing out of each nozzle are basically the same. This avoids the uneven distribution of catalyst caused by excessively high flow velocity when the catalyst flows out of the distributor, as well as the scouring of the distributor and other internal components when the high-velocity catalyst flows out. At the same time, a cobalt-based alloy wear-resistant layer is also coated on the inner surface of each nozzle 9, which can effectively resist the continuous scouring of the catalyst and greatly extend the service life of the nozzle.

[0021] In other embodiments of this utility model, the generatrix of the end cap can also be an arc.

[0022] In other embodiments of this invention, the cobalt-based alloy in this embodiment can be replaced with other wear-resistant materials, such as nickel-based alloys.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solution of this utility model, as long as they do not depart from the design and scope of the technical solution of this utility model, should be covered within the scope of the claims of this utility model.

Claims

1. A novel catalyst distributor, comprising an outer sleeve (2) and a stand-up pouch (10), characterized in that: The outer sleeve (2) includes a first sleeve (201) and a second sleeve (202) coaxially distributed. The bottom of the first sleeve (201) is provided with an annular top plate (6). A head (7) is provided between the outer edge of the top plate (6) and the top of the second sleeve (202). The bottom of the second sleeve (202) is provided with a fluidizing air ring pipe (1). The standpipe (10) passes through the first sleeve (201) and the head (7) and extends into the second sleeve (202). A number of nozzles (9) are provided on the head. The inner surfaces of the top plate (6), the head (7) and the nozzles (9) are coated with a wear-resistant layer (8).

2. The catalyst distributor with a novel structure according to claim 1, characterized in that: The generatrix of the head (7) is an elliptical arc.

3. The catalyst distributor with a novel structure according to claim 1, characterized in that: The wear-resistant layer (8) is a cobalt-based alloy wear-resistant layer.

4. The catalyst distributor with a novel structure according to claim 1, characterized in that: Several nozzles (9) on the end cap are arranged in a circular array.

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