CN217816724U

CN217816724U - Dual-fuel dual-swirl burner

Info

Publication number: CN217816724U
Application number: CN202220993343.2U
Authority: CN
Inventors: 宋文明; 李玉阁; 卢雪梅; 张玉福; 张�杰; 李煌; 王团亮; 魏利平; 闫渊
Original assignee: NORTHWEST UNIVERSITY; Machinery Industry Shanghai Lanya Petrochemical Equipment Testing Co ltd; Sinopec Zhongyuan Oilfield Co Puguang Branch; Sinopec North China Oil and Gas Co; Lanpec Technologies Ltd
Current assignee: NORTHWEST UNIVERSITY; Machinery Industry Shanghai Lanya Petrochemical Equipment Testing Co ltd; Sinopec Zhongyuan Oilfield Co Puguang Branch; Sinopec North China Oil and Gas Co; Lanpec Technologies Ltd
Priority date: 2022-04-27
Filing date: 2022-04-27
Publication date: 2022-11-15
Anticipated expiration: 2032-04-27

Abstract

The application discloses dual fuel dual cyclone burner includes: the combustion-supporting air duct is arranged in the air duct, the air duct comprises a gas pipeline, a double-rotational-flow flame stabilizing disc and a fuel pipeline which are coaxially arranged from outside to inside in the air duct, an external air loop is formed between the double-rotational-flow flame stabilizing disc and the air duct, and an internal air loop is formed between the double-rotational-flow flame stabilizing disc and the fuel pipeline; ignition electrodes are arranged at the gas outlet of the gas pipeline and the oil outlet of the fuel pipeline, and the gas outlet of the gas pipeline, the oil outlet of the fuel pipeline, the ignition electrodes and the double-swirl flow flame stabilizing disc are all arranged at the outlet end of the air duct. The double-cyclone flame stabilizing disc comprises a secondary cyclone and a primary cyclone arranged in the secondary cyclone, and the primary cyclone and the secondary cyclone adopt reverse cyclone structures. The method solves the problems of single fuel adaptability, low flexibility in adjusting the shape of combustion flame and insufficient combustion stability of the internal heat treatment process.

Description

Dual-fuel dual-swirl burner

Technical Field

The utility model relates to a combustion apparatus technical field especially relates to a dual fuel dual cyclone burner who uses during thermal treatment.

Background

The internal heat method heat treatment is a popular process for the integral heat treatment of domestic large-scale equipment at present. The heat treatment by internal heating method usually adopts light diesel oil as fuel, the fuel is fed into the tower by means of blower and nozzle and atomized, and the high-temp. air flow produced by continuously burning fuel oil is convected and conducted on the inner wall of tower body and the heat radiation of flame is acted, so that the temperature of tower body can be raised to the temp. required for heat treatment.

The fuel fed into the tower is typically atomized and the atomized fuel is brought into intimate contact with air. To do this, the burner head is usually provided with a flame holder. The flame stabilizing disc of the burner nozzle of the burner is also called a cyclone sheet, a swirler and the like, and mainly has the main functions of organizing airflow, enabling flame to be stably combusted, enabling the flame to be in a certain shape and being an important component accessory in the burner nozzle. In the internal heat method heat treatment process, the flame length is too long, so that fuel oil collides the wall, the fuel oil is coked, the combustion is incomplete, the pollutant emission is high, and the service life of equipment is short; the flame length is too short, the average temperature of the combustion chamber is too low, and the combustion and heat transfer efficiency is low. Under the condition of using diesel fuel, the mixing condition of atomized diesel and air is poor, so that the problems of insufficient combustion, high pollution emission, unstable flame and the like are caused. The rotary jet flow is an effective measure for strengthening combustion and organizing flame, strengthens mixing, shortens the length of the flame, improves the combustion efficiency, controls and reduces the emission of pollutants, and is widely applied to various combustors. The principle of swirl flow generated by burner flame is to arrange a swirl device (flame stabilizing disc/swirler) in the fluid flow passage, and the swirler generates tangential velocity and thus rotation to the flowing fluid. If strong swirl is generated, a recirculation zone is established in the central part of the flame during combustion, which recirculation zone plays an important role in stabilizing the flame and has a positive influence on the reduction of the flame length and the combustion intensity.

In the aspects of economy and environmental protection, the natural gas fuel is more economical and environment-friendly than the diesel fuel, and has certain advantages. In the application occasions of rich natural gas storage in China petrochemical industry, natural gas can be selected as fuel, or natural gas and diesel oil can be selected as mixed fuel to be supplied to combustion equipment.

Therefore, it is of great value and significance to develop a burner that can flexibly adjust the flame shape and improve fuel adaptability.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the problems of single fuel adaptability, low flexibility of combustion flame shape adjustment and insufficient combustion stability of the internal thermal method heat treatment process, and providing a dual-fuel dual-cyclone burner device used by the internal thermal method heat treatment process. This equipment adopts two whirl structures to stabilize the flame dish, realizes lower resistance, sufficient whirl intensity, can guarantee the intensive mixing of fuel, reaches the regional stable, flame stable combustion environment of whirl.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a dual fuel dual cyclone burner comprising:

one end of the air duct is provided with an inlet end, the other end of the air duct is provided with an outlet end, and a combustion-supporting air duct is arranged in the air duct; the fuel gas burner comprises a wind barrel, a fuel gas pipeline, a double-cyclone flame stabilizing disc and a fuel oil pipeline, wherein the gas pipeline, the double-cyclone flame stabilizing disc and the fuel oil pipeline are coaxially arranged in the wind barrel from outside to inside; ignition electrodes are arranged at the gas outlet of the gas pipeline and the oil outlet of the fuel pipeline; the gas outlet of the gas pipeline, the oil outlet of the fuel pipeline, the ignition electrode and the double-swirl flow flame stabilizing disc are all arranged at the outlet end of the air duct; wherein the content of the first and second substances,

the gas pipeline comprises a first gas pipeline and a second gas pipeline, the first gas pipeline and the second gas pipeline are uniformly distributed at intervals along the circumferential direction of the external air loop, the gas outlet of the first gas pipeline exceeds the double-cyclone flame stabilizing disc and gradually inclines towards the central axis of the double-cyclone flame stabilizing disc, and the gas outlet of the second gas pipeline exceeds the double-cyclone flame stabilizing disc and is parallel to the central axis of the double-cyclone flame stabilizing disc;

the double-cyclone flame stabilizing disc comprises a primary cyclone and a secondary cyclone, the primary cyclone is arranged in the secondary cyclone, a central through hole is formed in the center of the primary cyclone, and the central through hole is used for placing the fuel pipeline; the first-stage swirler and the second-stage swirler adopt reverse swirl structures, the two-stage swirler is in a ring shape formed by swirl impellers, and included angles among blades of the swirl impellers form a channel through which air flows.

Preferably, the dual cyclone flame stabilizing disc is fixedly arranged in the direction of the inner axis of the outlet end of the air duct, and a preset distance is formed between the outlet end of the dual cyclone flame stabilizing disc and the outlet end of the air duct, for example, the distance is 200mm.

Preferably, the primary cyclone comprises a first cover cylinder and a first cyclone impeller, the secondary cyclone comprises a second cover cylinder and a second cyclone impeller, the first cover cylinder is coaxially nested in the second cover cylinder, the first cyclone impeller is arranged in the first cover cylinder, the second cyclone impeller is arranged between the first cover cylinder and the second cover cylinder, blades of the first cyclone impeller and blades of the second cyclone impeller are uniformly distributed at intervals along the circumferential direction, the same inclination included angle is formed between each blade on the first cyclone impeller and the circumferential tangent line, and the same inclination included angle is formed between each blade on the second cyclone impeller and the circumferential tangent line; the first rotational flow impeller and the second rotational flow impeller are opposite in rotational flow direction.

More preferably, the blades of the first and second swirl impellers have different inclination angles.

In a preferred embodiment, the blades of the first swirl impeller are inclined at an angle of 45 ° and the blades of the second swirl impeller are inclined at an angle of 40 °.

More preferably, the number of the blades of the first swirl impeller and the number of the blades of the second swirl impeller are different.

In a preferred embodiment, the number of the blades of the first swirl impeller is 11, and the number of the blades of the second swirl impeller is 22.

Preferably, the outer diameter of the double-cyclone flame stabilizing disc is 250mm, the height of the double-cyclone flame stabilizing disc is 40mm, and the height of the inclined cyclone blades of the double-cyclone flame stabilizing disc is 30mm.

Preferably, a support is fixed on a pipe wall of the fuel pipeline close to an oil outlet of the fuel pipeline, and the double-cyclone flame stabilizing disc is fixed above the support.

Preferably, the oil outlet of the fuel pipeline is flush with the outlet end of the internal air loop at the center of the double-swirl flame stabilizing disc.

Preferably, an atomizing nozzle is arranged at the oil outlet of the fuel pipeline.

Preferably, the ignition electrode comprises a first high-energy ignition electrode and a second high-energy ignition electrode, the ignition end of the first high-energy ignition electrode is arranged close to the oil outlet of the fuel pipeline, and the ignition end of the second high-energy ignition electrode is arranged close to the gas outlet of the fuel pipeline.

Preferably, the fuel pipeline is communicated with an external fuel input assembly, and a fan for blowing air flow into the air duct is further arranged at the inlet end of the air duct.

Compared with the prior art, the technical scheme of the utility model following beneficial effect has:

the double-swirl flame stabilizing disc in the application has lower resistance and stronger swirl strength compared with a common single-swirl flame stabilizing disc, so that the fuel and the air are mixed more sufficiently, and the formed flame length can be shortened.

The ignition performance of the fuel is influenced by the cyclone effect formed by the flame stabilizing disc to a certain extent, and according to the air flow condition, the cyclone flame can form a backflow area, so that the ignition stability is improved by absorbing the heat of self combustion of the coil and the high-temperature flue gas of the hearth. The swirl strength of the double-swirl flame stabilizing disc can be adjusted, and the double-swirl flame stabilizing disc with different blade numbers and inner and outer swirl directions can be replaced according to actual needs, so that the flame shape can be adjusted flexibly. Meanwhile, in order to control the width of flame generated by a burner used for internal combustion heat treatment, an annular channel is arranged between the double-cyclone flame stabilizing disc and an external air duct, and the flame can be wrapped by air flowing through the annular channel.

According to the method and the device, the flowing condition of the medium flowing through the double-cyclone flame stabilizing disc can be improved by designing the number of the blades, the size of the blades and the inclination angle of the blades of the double-cyclone flame stabilizing disc, and the conditions of large resistance, low cyclone strength and insufficient fuel mixing under a common single-cyclone flame stabilizing disc are improved.

Drawings

The accompanying drawings, which form a part of the present application, are included to provide a further understanding of the present application, and the description and illustrative embodiments of the present application are provided to explain the present application and not to limit the present application. In the drawings:

FIG. 1 is a schematic view of a head construction of a dual cyclone dual fuel burner;

FIG. 2 isbase:Sub>A cross-sectional view of the head A-A of the dual-swirl dual-fuel burner of FIG. 1;

fig. 3 is a comparison result of numerical simulation of the double-swirl flame stabilizing disc and the single-swirl flame stabilizing disc.

Illustration of the drawings:

1. a first gas line; 2. a second gas line; 3. a fuel line; 4. a first high energy ignition electrode; 5. a second high energy ignition electrode; 6. a primary swirler; 7. a secondary cyclone; 8. a support; 9. an inner air loop; 10. an external air loop; 11. an air duct.

Detailed Description

In order to make the objects, technical solutions and effects of the present invention clearer and clearer, the present invention will be described in further detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the above-described drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order, it being understood that the data so used may be interchanged under appropriate circumstances. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions.

Example (b):

fig. 1 isbase:Sub>A schematic structural view ofbase:Sub>A dual cyclone dual fuel burner head, and fig. 2 isbase:Sub>A sectional view of the dual cyclone dual fuel burner headbase:Sub>A-base:Sub>A of fig. 1.

As shown in fig. 1 and fig. 2, the dual-fuel dual-cyclone burner according to the embodiment includes an air duct 11 with a combustion-supporting air duct inside a housing, and a fuel pipeline 3, a gas pipeline, an ignition electrode and a dual-cyclone flame-stabilizing disk which are arranged inside the air duct 11. One end of the air duct 11 is provided with an inlet end, and the other end is provided with an outlet end. The gas pipeline, the double-cyclone flame stabilizing disc formed by the primary cyclone 6 and the secondary cyclone 7 and the fuel pipeline 3 are coaxially arranged in the air duct 11 from outside to inside in sequence. And a support 8 is fixed on the pipe wall of the fuel pipeline 3 close to the oil outlet, and the double-cyclone flame stabilizing disc is fixed above the support 8. An external air loop 10 is formed between the double-swirl flame stabilizing disc and the air duct 11, and an internal air loop 9 is formed between the double-swirl flame stabilizing disc and the fuel pipeline 3. Ignition electrodes are arranged at the gas outlet of the gas pipeline and the oil outlet of the fuel pipeline 3, and the gas outlet of the gas pipeline, the oil outlet of the fuel pipeline 3, the ignition electrodes and the double-cyclone flame stabilizing disc are all arranged at the outlet end of the air duct 11.

The gas pipeline includes first gas pipeline 1 and second gas pipeline 2, first gas pipeline 1 and second gas pipeline 2 are followed the even interval distribution in circumference of outside air loop 10. The gas outlet of the first gas pipeline 1 gradually inclines towards the central shaft of the double-swirl flow flame stabilizing disc, namely the gas outlet of the first gas pipeline 1 has a certain angle and the direction is inward. And the gas outlet of the second fuel gas pipeline 2 is parallel to the central shaft of the double-cyclone flame stabilizing disc, namely the second fuel gas pipeline 2 is a vertical fuel gas pipeline.

The air outlets of the first gas pipeline 1 and the second gas pipeline 2 both exceed one part of the double-cyclone flame stabilizing disc, the exceeding part sprays out gas, and the gas diffuses towards the center of the double-cyclone flame stabilizing disc under the entrainment action of air to realize stable combustion. The second gas line 2 is advantageous for increasing the length of the flame. The gas ejected from the first gas pipeline 1 with an angle is diffused and combusted towards the center under the action of the air flow which is generated and sucked towards the center through the double-swirl flame stabilizing disc, and the gas ejected from the second gas pipeline 2 is diffused and combusted in the external air loop 10. After the air passes through the double-rotational-flow flame stabilizing disc, a stable backflow area is formed above the double-rotational-flow flame stabilizing disc, and the backflow area enables the air and the fuel to be fully mixed, so that stable combustion is realized.

The double-cyclone flame stabilizing disc comprises a primary cyclone 6 and a secondary cyclone 7, the primary cyclone 6 is arranged in the secondary cyclone 7, a central through hole is formed in the center of the primary cyclone 6, and the central through hole is used for placing the fuel pipeline 3. The first-stage swirler 6 and the second-stage swirler 7 adopt reverse swirl structures, the two-stage swirler is in a ring shape formed by swirl impellers, and included angles between blades of the swirl impellers form a channel through which air flows.

The primary cyclone 6 comprises a first cover cylinder and a first cyclone impeller, the secondary cyclone 7 comprises a second cover cylinder and a second cyclone impeller, the first cover cylinder is coaxially nested in the second cover cylinder, the first cyclone impeller is arranged in the first cover cylinder, and the second cyclone impeller is arranged between the first cover cylinder and the second cover cylinder. The blades of the first rotational flow impeller and the blades of the second rotational flow impeller are uniformly distributed at intervals along the circumferential direction, the same inclined included angle is formed between each blade on the first rotational flow impeller and a circumferential tangent line, and the same inclined included angle is formed between each blade on the second rotational flow impeller and the circumferential tangent line. The first rotational flow impeller and the second rotational flow impeller are opposite in rotational flow direction.

The ignition performance of the fuel is influenced by the rotational flow effect formed by the flame stabilizing disc to a certain extent, the rotational flow flame can form a backflow area according to the air flow condition, and the ignition stability is improved by absorbing the heat of self combustion of the coil and the high-temperature smoke of the hearth. The swirl strength of the double-swirl flame stabilizing disc can be adjusted, and the double-swirl flame stabilizing disc with different blade numbers and inner and outer swirl directions can be replaced according to actual needs, so that the flame shape can be adjusted flexibly. Meanwhile, in order to control the width of the flame generated by the burner used for the internal combustion heat treatment, a loop is arranged between the double-swirl flame stabilizing disc and the external wind barrel 11, and the flame can be wrapped by the air flowing through the loop.

The flowing condition of a medium flowing through the double-cyclone flame stabilizing disc can be improved by designing the number of the blades, the size of the blades and the inclination angle of the blades of the double-cyclone flame stabilizing disc. In a preferred embodiment, the outer diameter of the double-cyclone flame stabilizing disc can be designed to be 250mm, the height of the double-cyclone flame stabilizing disc is 40mm, and the height of the inclined blade is 30mm; the inclination angle of the blades of the first swirl impeller may be set to 45 °, the number of the blades may be 11, the inclination angle of the blades of the second swirl impeller may be set to 40 °, and the number of the blades may be 22. The double-swirl flame stabilizing disc improves the conditions of large resistance, low swirl strength and insufficient fuel mixing under the common single-swirl flame stabilizing disc.

The center of the double-cyclone flame stabilizing disc is provided with a fuel pipeline 3, a support 8 is fixed on the fuel pipeline 3, and the double-cyclone flame stabilizing disc is fixed above the support 8. The oil outlet of the fuel pipeline 3 is flush with the outlet end of the internal air loop 9 at the center of the double-swirl flame stabilizing disc. The oil outlet of the fuel oil pipeline 3 is provided with an atomizing nozzle, and the fuel oil is atomized and sprayed out with a certain cone angle and is uniformly mixed with air under the action of swirling gas. Part of the air flows through the inner air circuit 9 in the centre, supplementing oxygen to the central combustion.

In order to make the fuel smoothly go on, a high-energy ignition electrode is arranged at a certain distance from the fuel outlet, and specifically comprises a first high-energy ignition electrode 4 and a second high-energy ignition electrode 5. The ignition end of the first high-energy ignition electrode 4 is close to the oil outlet of the fuel pipeline 3, and the ignition end of the second high-energy ignition electrode 5 is close to the gas outlet of the fuel pipeline. The length of the wind barrel 11 exceeds 200mm of the outlet end of the double-swirl flame stabilizing disc, a certain space is reserved for the sufficient mixing of air and fuel, and the wind barrel also plays a role in stabilizing flame. Combustion-supporting air flows into the inlet end of the air duct 11, and the combustion-supporting air is separated under the action of the double-cyclone flame stabilizing disc and the inner wall of the air duct 11.

The dual-fuel double-cyclone burner can select a mode of single-fuel combustion and mixed combustion of two fuels. When the fuel gas is selected to be combusted independently, the fuel gas is sprayed out through the first fuel gas pipeline 1 and the second fuel gas pipeline 2. The fuel gas is sprayed towards the center direction of the double-cyclone flame stabilizing disc under the action of the first fuel gas pipeline 1 with a certain angle, the fuel gas flowing towards the center direction of the double-cyclone flame stabilizing disc is sucked above the double-cyclone flame stabilizing disc under the action of the double-cyclone flame stabilizing disc, and is ignited after certain energy is applied to the second high-energy ignition electrode 5, so that stable flame is formed above the double-cyclone flame stabilizing disc. The presence of the second gas line 2 increases the extent of the distribution of the fuel in the axial direction, and thus the extent of the flame length. When fuel oil is used alone, the fuel flows in through the fuel line 3 and is atomized and ejected to form a droplet spray. And a stable mixing area is formed with air under the entrainment effect formed by the double-swirl flame stabilizing disc and is ignited by the first high-energy ignition electrode 4. When a single fuel is used for operation, under the condition of insufficient fuel, another fuel can be injected according to the requirement, so that the operation stop condition caused by insufficient fuel can be avoided. When dual fuels are used for operation, on the one hand, one fuel is ignited at the high temperature of the other fuel when operating on the other fuel; on the other hand, a small amount of fuel oil or fuel gas fuel is firstly introduced, after the fuel oil or fuel gas fuel is ignited under the action of the ignition electrode, another fuel is introduced, and the fuel oil or fuel gas fuel works in the mode that a small fire ignites a large fire.

The double-cyclone flame stabilizing disc has the function that when combustion-supporting air flows through the double-cyclone flame stabilizing disc, strong cyclone flow is formed above the double-cyclone flame stabilizing disc, so that rotary jet combustion is formed. The top of two whirl steady flame dish can form a backward flow district simultaneously, and this backward flow district can bring back partial fuel and form the postcombustion, has shortened flame length when making the burning more abundant, has promoted combustion strength.

Compared with the single-flow-selection flame stabilizing disc which is common in the past, the double-swirl flame stabilizing disc is found to have lower resistance compared with the single-swirl flame stabilizing disc after numerical simulation, and the double-swirl flame stabilizing disc is proved to be capable of providing good flowing capacity so that the flue gas can be smoothly discharged from a flue gas outlet during combustion. The results are shown in FIG. 3.

To sum up, the application provides a dual-fuel dual-cyclone burner device used in the internal heat method heat treatment process, and solves the problems of single fuel adaptability, low flexibility of combustion flame shape adjustment and insufficient combustion stability of the internal heat method heat treatment process. This application adopts the steady flame dish of two whirl structures, and the steady flame dish of more general single whirl has lower resistance, stronger whirl intensity, can guarantee the intensive mixing of fuel, reaches whirl regional stability, flame stabilization's combustion environment.

The above detailed description of the embodiments of the present invention is only for exemplary purposes, and the present invention is not limited to the above described embodiments. Any equivalent modifications and substitutions to those skilled in the art are also within the scope of the present invention. Accordingly, variations and modifications in equivalents may be made without departing from the spirit and scope of the invention, which is intended to be covered by the following claims.

Claims

1. A dual fuel dual swirl burner, comprising:

2. The dual-fuel dual-swirl burner of claim 1, wherein the dual-swirl flame stabilizing disc is fixedly arranged in the direction of the inner axis of the outlet end of the air duct, and the outlet end of the dual-swirl flame stabilizing disc is 200mm away from the outlet end of the air duct.

3. The dual fuel dual cyclone burner of claim 1, wherein the primary cyclone comprises a first shroud and a first cyclone impeller, the secondary cyclone comprises a second shroud and a second cyclone impeller, the first shroud is coaxially nested within the second shroud, the first cyclone impeller is disposed within the first shroud, the second cyclone impeller is disposed between the first shroud and the second shroud, the first and second cyclone impeller vanes are uniformly circumferentially spaced, the first and second cyclone impeller vanes have the same inclination angle with the circumferential tangent line, and the second cyclone impeller vanes have the same inclination angle with the circumferential tangent line; the first rotational flow impeller and the second rotational flow impeller are opposite in rotational flow direction.

4. A dual fuel dual swirl burner as claimed in claim 3, wherein the vanes of the first swirl impeller and the vanes of the second swirl impeller are at different angles of inclination.

5. A dual fuel dual cyclone burner as claimed in claim 4, wherein the angle of inclination of the vanes of the first cyclone impeller is 45 ° and the angle of inclination of the vanes of the second cyclone impeller is 40 °.

6. A dual fuel dual cyclone burner as claimed in claim 3, wherein the number of vanes of the first cyclone impeller and the second cyclone impeller are different.

7. The dual-fuel dual-cyclone burner of claim 1, wherein a support is fixed on a pipe wall of the fuel pipeline close to the fuel outlet, and the dual-cyclone flame stabilizing disc is fixed above the support.

8. A dual fuel dual cyclone burner as claimed in claim 1 wherein the fuel outlet of the fuel line is flush with the outlet end of the internal air loop at the center of the dual cyclone flame stabilizing disk.

9. A dual fuel dual cyclone burner as claimed in claim 1, wherein an atomizing nozzle is provided at the oil outlet of the fuel line.

10. The dual fuel dual cyclone burner of claim 1, wherein the ignition electrode comprises a first high energy ignition electrode and a second high energy ignition electrode, the ignition end of the first high energy ignition electrode is disposed proximate to the oil outlet of the fuel gas line, and the ignition end of the second high energy ignition electrode is disposed proximate to the gas outlet of the fuel gas line.