Multistage venturi structure wear-resistant flue gas nozzle device

Abstract

The utility model discloses a multistage venture structure wear -resisting flue gas nozzle device belongs to catalytic cracking device's technical field, including nozzle casing and wear -resistant lining, nozzle casing one end sets up nozzle entrance, and the other end is connected main flue, wear -resistant lining sets up in nozzle casing inside, nozzle casing inside is sequentially provided with entering section, contraction section, diffusion section and communicating section along the flue gas flow direction, the middle passage of contraction section and diffusion section is communicated through the link section, and the cross section area of contraction section gradually reduces, and the cross section area of diffusion section gradually increases, the communicating section is into the straight pipe shape, and one end communicates diffusion section, and the other end communicates main flue, and the communicating section is connected one end with main flue and is provided with orifice plate, the junction of entering section and contraction section lateral wall is arc shape setting, and orifice plate is inclined to the communicating section axis setting, the utility model satisfies the fluid dynamics requirement, solves the wear and tear problem of nozzle, also reduces the collision of flue gas particle to the lateral wall of main flue.

Description

Technical Field

[0001] This utility model belongs to the technical field of catalytic cracking equipment, and more specifically relates to a multi-stage venturi structure wear-resistant flue gas nozzle device. Background Technology

[0002] Currently, the critical velocity nozzle is a key component in catalytic cracking units for controlling the pressure balance of the tertiary cyclone separator and the metered entry of flue gas into the flue gas turbine. Its operating temperature can reach 700℃, the flue gas velocity can reach 200m / s, and it is subjected to erosion from the airflow containing a small amount of catalyst particles. Its operating condition directly affects the efficiency of catalyst recovery in the tertiary cyclone separator, the power generation capacity of the flue gas turbine, and the stable operation of the turbine. Therefore, how to provide a multi-stage venturi structure wear-resistant flue gas nozzle device is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0003] In view of this, the present invention provides a multi-stage Venturi structure wear-resistant flue gas nozzle device, which adopts the following technical solution: A multi-stage Venturi structure wear-resistant flue gas nozzle device includes a nozzle housing and a wear-resistant lining; one end of the nozzle housing is provided with a nozzle inlet, and the other end is connected to the main flue; the wear-resistant lining is disposed inside the nozzle housing; the inside of the nozzle housing is arranged sequentially along the flue gas flow direction as an inlet section, a contraction section, a diffusion section, and a connecting section; the contraction section and the diffusion section are connected by a connecting section, the cross-sectional area of ​​the contraction section gradually decreases, and the cross-sectional area of ​​the diffusion section gradually increases; the connecting section is in the shape of a straight tube, one end of which is connected to the diffusion section, and the other end of which is connected to the main flue; an orifice plate is provided at the end of the connecting section connected to the main flue.

[0004] Furthermore, the nozzle housing is connected to the main flue pipe via a flange.

[0005] Furthermore, the sidewall at the connection between the entry section and the contraction section is arc-shaped.

[0006] Furthermore, the perforated plate is inclined relative to the axis of the connecting section.

[0007] The beneficial effects of this utility model are as follows: This invention provides a multi-stage Venturi structure wear-resistant flue gas nozzle device. The nozzle is equipped with four sections: an inlet section, a contraction section, a diffusion section, and a connecting section, which meets the requirements of fluid dynamics. The inlet section and the arc-shaped connecting section connected to the contraction section stabilize the flow state of the fluid. The structural performance of the nozzle is improved by setting the contraction section and the diffusion section, and the wear problem of existing critical flow velocity nozzles is solved. At the same time, the inclined orifice plate also reduces the collision of flue gas particles with the side wall of the main flue. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0009] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0010] In the figure: 1-Inlet section; 2-Contraction section; 3-Diffusion section; 4-Connecting section; 5-Orifice plate; 11-Nozzle housing; 12-Wear-resistant lining. Detailed Implementation

[0011] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0012] Please see the appendix Figure 1 This utility model provides a multi-stage Venturi structure wear-resistant flue gas nozzle device, including a nozzle housing 11 and a wear-resistant lining 12; one end of the nozzle housing 11 is provided with a nozzle inlet, and the other end is connected to the main flue; the wear-resistant lining 12 is disposed inside the nozzle housing 11.

[0013] The nozzle housing 11 is connected to the main flue pipe via a flange; the nozzle housing 11 is provided with an inlet section 1, a contraction section 2, a diffusion section 3 and a connecting section 4 in sequence along the flue gas flow direction.

[0014] The sidewall at the connection between the inlet section 1 and the converging section 2 is arc-shaped to prevent the flue gas from backflowing after entering the inlet section 1 from the nozzle inlet and accumulating at the connection. At the same time, it can reduce the impact and wear of the sidewall caused by the local secondary vortex due to the reduction of the cross-sectional area of ​​the converging section 2.

[0015] The contraction section 2 and the diffusion section 3 are connected by a connecting section. The cross-sectional area of ​​the contraction section 2 gradually decreases, while the cross-sectional area of ​​the diffusion section 3 gradually increases.

[0016] The connecting section 4 is a straight tube, with one end connected to the diffuser section 3 and the other end connected to the main flue. An orifice plate 5 is provided at the end of the connecting section 4 where it connects to the main flue. The orifice plate 5 is inclined relative to the axis of the connecting section 4, which reduces the radial component of the flue gas flow when entering the main flue, thus reducing particle collisions with the sidewalls of the main flue. The arc-shaped transition section between the inlet section 1 and the contraction section 2 forms a first-stage processing unit, used to stabilize the flow state of the fluid entering the nozzle; the connecting section between the contraction section 2 and the diffuser section 3 forms a second-stage processing unit, increasing the fluid velocity through pressure difference; the orifice plate 5 at the end of the connecting section 4 forms a third-stage processing unit, used to reduce the radial component of the flue gas flow when entering the main flue and to uniformly distribute the fluid velocity.

[0017] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0018] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. 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 the present invention. Therefore, the present invention 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 disclosed herein.

Claims

1. A multi-stage Venturi structure wear-resistant flue gas nozzle device, characterized in that, It includes a nozzle housing (11) and a wear-resistant lining (12); one end of the nozzle housing (11) is provided with a nozzle inlet and the other end is connected to the main flue; the wear-resistant lining (12) is disposed inside the nozzle housing (11); the nozzle housing (11) is provided with an inlet section (1), a contraction section (2), a diffusion section (3) and a connecting section (4) in sequence along the flue gas flow direction; the contraction section (2) and the diffusion section (3) are connected by a connecting section, the cross-sectional area of ​​the contraction section (2) gradually decreases and the cross-sectional area of ​​the diffusion section (3) gradually increases; the connecting section (4) is in the shape of a straight tube, one end is connected to the diffusion section (3) and the other end is connected to the main flue; a perforated plate (5) is provided at the end of the connecting section (4) connected to the main flue.

2. The multi-stage Venturi structure wear-resistant flue gas nozzle device according to claim 1, characterized in that, The nozzle housing (11) is connected to the main flue pipe via a flange.

3. The multi-stage Venturi structure wear-resistant flue gas nozzle device according to claim 1, characterized in that, The sidewall at the connection between the entry section (1) and the contraction section (2) is arc-shaped.

4. The multi-stage Venturi structure wear-resistant flue gas nozzle device according to claim 1, characterized in that, The orifice plate (5) is inclined relative to the axis of the connecting section (4).

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