Ignition device and boiler

Abstract

According to the ignition device and the boiler, one end of a pipeline is communicated with the feeding end of a shell, pulverized coal is conveyed to the shell, a front cylinder is arranged in the shell, an arc plasma generator is arranged at the feeding end of the front cylinder, a microwave reaction ring is arranged on the shell in a sleeved mode, and a microwave induction unit is connected with the microwave reaction ring. The microwave reaction ring feeds microwave energy formed by the microwave induction unit into the front cylinder and the first center cylinder, the first center cylinder is communicated with the discharging end of the front cylinder, pulverized coal is conveyed into the shell through a pipeline, part of the pulverized coal enters the front cylinder, at the moment, the microwave reaction ring feeds the microwave energy formed by the microwave induction unit into the front cylinder, and the pulverized coal enters the front cylinder. Plasma arcs generated by the arc plasma generator can be enhanced, meanwhile, part of pulverized coal is preheated, after the arc plasmas are enhanced by microwave energy, the pulverized coal preheated by the microwave energy can be ignited at the same time, and ignition is achieved.

Description

Technical Field

[0001] The utility model relates to the field of coal-fired boilers, and specifically to an ignition device and a boiler. Background Art

[0002] At present, the boilers in thermal power plants are mainly pulverized coal furnaces. The ignition device of a pulverized coal furnace usually consists of a microwave transmitting device, a microwave amplifier, a cooling device and a resonant cavity, which can make the boiler furnace in a microwave environment, and the polar molecules inside the pulverized coal oscillate continuously and mix fully with oxygen, promoting the full combustion of the pulverized coal.

[0003] However, the existing boilers have limitations in terms of coal quality adaptability. When dealing with difficult-to-burn coals such as inferior bituminous coal and lean coal, due to their low volatile content, high ignition temperature and slow flame propagation speed, etc., the existing boilers cannot rely solely on arc plasma to successfully ignite. Summary of the Utility Model

[0004] In view of this, the embodiments of the present utility model provide an ignition device and a boiler to solve the problem that the ignition device of the existing boiler cannot successfully ignite when facing difficult-to-burn coals such as inferior bituminous coal and lean coal.

[0005] To achieve the above object, the embodiments of the present utility model provide the following technical solutions:

[0006] The first aspect of the present utility model discloses an ignition device, including: a housing, an arc plasma generator, a front cylinder, a microwave reaction ring, a microwave inducer, a pipeline and a first central cylinder;

[0007] One end of the pipeline is communicated with the feeding end of the housing for conveying pulverized coal to the housing;

[0008] The front cylinder is arranged inside the housing;

[0009] The arc plasma generator is arranged at the feeding end of the front cylinder for generating arc plasma to heat the pulverized coal in the front cylinder;

[0010] The microwave reaction ring is sleeved on the housing;

[0011] The microwave inducer is connected to the microwave reaction ring, and the microwave reaction ring is used for feeding the microwave energy formed by the microwave inducer into the front cylinder and the first central cylinder;

[0012] The first end of the first central cylinder is communicated with the discharging end of the front cylinder, wherein the diameter of the first central cylinder is larger than that of the front cylinder.

[0013] Preferably, the housing is of a cylindrical structure.

[0014] Preferably, the front cylinder, the housing and the first central cylinder are coaxially arranged.

[0015] Preferably, the microwave inducer includes a magnetron and a waveguide;

[0016] The magnetron is connected to the microwave reaction ring through the waveguide.

[0017] Preferably, the power range of the arc plasma generator is 5KW - 200kW.

[0018] Preferably, the power range of the microwave inducer is 0.5KW - 70KW.

[0019] Preferably, it further includes a second central cylinder;

[0020] One end of the second central cylinder communicates with the second end of the first central cylinder, wherein the diameter of the second central cylinder is greater than that of the first central cylinder.

[0021] Preferably, the microwave reaction ring includes a first reaction ring and a second reaction ring;

[0022] Both the first reaction ring and the second reaction ring are sleeved on the housing. Among them, the first reaction ring is used to enhance the plasma arc generated by the arc plasma generator and preheat the pulverized coal, and the second reaction ring is used to induce and heat the high-temperature fuel gas flow in the first central cylinder and the second central cylinder.

[0023] Preferably, the second central cylinder is coaxially arranged with the first central cylinder.

[0024] In the second aspect of the present invention, a boiler is disclosed, including the ignition device disclosed in the first aspect of the present invention.

[0025] Based on the ignition device and boiler provided by the above-mentioned present invention, one end of the pipeline is communicated with the feeding end of the housing, and the pulverized coal is conveyed to the housing. The front cylinder is arranged in the housing, and the arc plasma generator is arranged at the feeding end of the front cylinder. Thus, the pulverized coal in the front cylinder can be heated by generating arc plasma. And the microwave reaction ring is sleeved on the housing, the microwave inducer is connected to the microwave reaction ring, and the microwave reaction ring feeds the microwave energy formed by the microwave inducer into the front cylinder and the first central cylinder. The first end of the first central cylinder is communicated with the discharging end of the front cylinder, and the diameter of the first central cylinder is greater than that of the front cylinder. Through the disclosed ignition device, when the pulverized coal is conveyed into the housing through the pipeline, part of the pulverized coal enters the front cylinder. At this time, the microwave reaction ring feeds the microwave energy formed by the microwave inducer into the front cylinder, which can enhance the plasma arc generated by the arc plasma generator and preheat part of the pulverized coal at the same time. After the arc plasma is enhanced by the microwave energy, it can ignite the pulverized coal that is simultaneously preheated by the microwave energy, realizing ignition. Compared with the existing boiler ignition device, the present application can improve the ignition performance of difficult-to-burn coals such as inferior bituminous coal and lean coal through multi-point coupling, and realize the ignition of difficult-to-burn pulverized coal. Description of the Drawings

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained according to the provided drawings.

[0027] Figure 1 Structural schematic diagram of an ignition device provided by an embodiment of the present invention;

[0028] Figure 2 Structural schematic diagram of another ignition device provided by an embodiment of the present invention.

[0029] Among them, there are a housing 1, an arc plasma generator 2, a front cylinder 3, a microwave reaction ring 4, a first reaction ring 41, a second reaction ring 42, a magnetron 51, a waveguide 52, a pipeline 6, a first central cylinder 7, and a second central cylinder 8. Specific embodiments

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0031] An embodiment of the present invention provides an ignition device. Refer to Figures 1 to 2 , Figure 1 , which is a structural schematic diagram of the ignition device. The ignition device includes: a housing 1, an arc plasma generator 2, a front cylinder 3, a microwave reaction ring 4, a microwave inducer, a pipeline 6, and a first central cylinder 7;

[0032] One end of the pipeline 6 is communicated with the feeding end of the housing 1 for conveying pulverized coal to the housing 1;

[0033] The front cylinder 3 is arranged inside the housing 1;

[0034] The arc plasma generator 2 is arranged at the feeding end of the front cylinder 3 for generating arc plasma to heat the pulverized coal in the front cylinder 3;

[0035] The microwave reaction ring 4 is sleeved on the housing 1;

[0036] The microwave inducer is connected to the microwave reaction ring 4, and the microwave reaction ring 4 is used to feed the microwave energy formed by the microwave inducer into the front cylinder 3 and the first central cylinder 7;

[0037] The first end of the first central cylinder 7 is communicated with the discharge end of the pre-chamber 3, wherein the diameter of the first central cylinder 7 is larger than that of the pre-chamber 3.

[0038] It should be noted that the main function of the arc plasma generator 2 is to generate arc plasma and heat part of the pulverized coal entering the pre-chamber 3 to improve the temperature and activity of the fuel. The plasma generated by the arc plasma generator 2 will be fed with microwave energy to enhance the activity.

[0039] There is a narrow gap between the pre-chamber 3 and the arc plasma generator 2, so that a part of the primary air-pulverized coal flow enters the pre-chamber 3 through this gap and is ignited. The pre-chamber 3 can protect the fuel pretreated by the plasma and prevent the pulverized coal that has not been plasma-treated outside the pre-chamber 3 from mixing with it, and pyrolyze and activate these fuels by concentrating the energy of the plasma generator power in the pre-chamber 3.

[0040] A first central cylinder 7 is installed behind the pre-chamber 3. The first central cylinder 7 expands and further protects the flame coming from the pre-chamber 3 to improve the ignition effect. The cross-sectional area of the central cylinder is larger than that of the pre-chamber 3 to reduce the flow velocity in the cavity, which is beneficial to the ignition of the pulverized coal flow and the continuous combustion of the flame.

[0041] In the embodiment of the present utility model, one end of the pipeline 6 is communicated with the feeding end of the housing 1, and the pulverized coal is conveyed to the housing 1. The pre-chamber 3 is arranged in the housing 1, and the arc plasma generator 2 is arranged at the feeding end of the pre-chamber 3. Furthermore, the pulverized coal in the pre-chamber 3 can be heated by generating arc plasma, and the microwave reaction ring 4 is sleeved on the housing 1, and the microwave inducer is connected to the microwave reaction ring 4. The microwave reaction ring 4 feeds the microwave energy formed by the microwave inducer into the pre-chamber 3 and the first central cylinder 7. The first end of the first central cylinder 7 is communicated with the discharge end of the pre-chamber 3, and the diameter of the first central cylinder 7 is larger than that of the pre-chamber 3. Through the above disclosed ignition device, when the pulverized coal is conveyed into the housing 1 through the pipeline 6, part of the pulverized coal will enter the pre-chamber 3. At this time, the microwave reaction ring 4 feeds the microwave energy formed by the microwave inducer into the pre-chamber 3, which can enhance the plasma arc generated by the arc plasma generator 2 and preheat part of the pulverized coal at the same time. After the arc plasma is enhanced by the microwave energy, it can ignite the pulverized coal that is preheated by the microwave energy at the same time, realizing ignition. Compared with the existing boiler ignition device, the present application can improve the ignition performance of difficult-to-burn coals such as inferior bituminous coal and lean coal through the multi-point coupling effect, and realize the ignition of difficult-to-burn pulverized coal.

[0042] Specifically, the housing 1 is of a cylindrical structure.

[0043] It should be noted that the housing 1 can be of a cylindrical structure or a polygonal cylindrical structure, and those skilled in the art can choose according to needs.

[0044] Furthermore, the front cylinder 3, the housing 1, and the first central cylinder 7 are all coaxially arranged.

[0045] It should be noted that by coaxially arranging the front cylinder 3 and the housing 1, it can be ensured that the gap formed between the outer wall of the front cylinder 3 and the housing 1 is an annular structure, so that the microwave energy generated by the microwave reaction ring 4 can be evenly fed into the front cylinder 3 from all around.

[0046] And by coaxially arranging the first central cylinder 7 and the front cylinder 3, the microwave energy generated by the microwave reaction ring 4 can be evenly fed into the first central cylinder 7 from all around.

[0047] Specifically, the microwave inducer includes a magnetron 51 and a waveguide 52;

[0048] The magnetron 51 is connected to the microwave reaction ring 4 through the waveguide 52.

[0049] It should be noted that the magnetron 51 generates high-power microwave energy, and through the transmission of the waveguide 52, the microwave energy is transmitted to the microwave reaction ring 4.

[0050] Furthermore, the power range of the arc plasma generator 2 is 5KW - 200KW.

[0051] It should be noted that the power range of the arc plasma generator 2 can be 5KW, or 200KW, or 180KW, and no specific limitation is made here. In the specific implementation process of this application, when the power range of the arc plasma generator 2 is 5KW - 200KW, the temperature of the arc plasma can reach 3000°C - 5000°C.

[0052] Specifically, the power range of the microwave inducer is 0.5KW - 70KW.

[0053] It should be noted that the power of the microwave inducer can be 0.5KW, or 70KW, or 30KW, and those skilled in the art can select according to requirements.

[0054] It is worth noting that the power of the microwave inducer can be appropriately adjusted according to different coal qualities.

[0055] Preferably, the velocity of the pulverized coal air flow in this application is preferably 10 - 25m / s, but is not limited thereto.

[0056] Preferably, the temperature in this application is preferably 20°C - 80°C, but is not limited thereto.

[0057] Preferably, the frequency of the microwave generating device in this application is preferably 915MHz or 2450MHz, but is not limited thereto.

[0058] Further, the ignition device further includes: a second central cylinder 8;

[0059] One end of the second central cylinder 8 communicates with the second end of the first central cylinder 7, wherein the diameter of the second central cylinder 8 is greater than that of the first central cylinder 7.

[0060] It should be noted that by communicating one end of the second central cylinder 8 with the second end of the first central cylinder 7 and making the diameter of the second central cylinder 8 greater than that of the first central cylinder 7, the flame coming from the pre-chamber 3 can be further expanded and protected, improving the ignition effect. The cross-sectional area of the central cylinder is greater than that of the pre-chamber 3 to reduce the flow rate in the chamber, which is beneficial to the ignition of the pulverized coal air flow and the continuous combustion of the flame.

[0061] Preferably, the ignition device further includes: a third central cylinder;

[0062] One end of the third central cylinder communicates with the other end of the second central cylinder 8, and the diameter of the third central cylinder is greater than that of the second central cylinder 8.

[0063] Preferably, the third central cylinder is coaxially arranged with the second central cylinder 8.

[0064] Specifically, the microwave reaction ring 4 includes: a first reaction ring 41 and a second reaction ring 42;

[0065] Both the first reaction ring 41 and the second reaction ring 42 are sleeved on the housing 1. Among them, the first reaction ring 41 is used to enhance the plasma arc generated by the arc plasma generator 2 and preheat the pulverized coal, and the second reaction ring 42 is used to inductively heat the high-temperature fuel gas flow in the first central cylinder 7 and the second central cylinder 8.

[0066] It should be noted that by setting the microwave reaction ring 4 as the first reaction ring 41 and the second reaction ring 42, the first reaction ring 41 enhances the plasma arc generated by the arc plasma generator 2 and preheats the pulverized coal, and the second reaction ring 42 inductively heats the high-temperature fuel gas flow in the first central cylinder 7 and the second central cylinder 8, which can accurately enhance the key area and can further cultivate and protect the ignition.

[0067] Specifically, the second central cylinder 8 is coaxially arranged with the first central cylinder 7.

[0068] It should be noted that by coaxially arranging the second central cylinder 8 with the first central cylinder 7, the microwave energy generated by the second reaction ring 42 can be evenly fed into the second central cylinder 8 from all around.

[0069] Preferably, the ratio of the cross-sectional area of the first central cylinder 7 to that of the pre-chamber 3 is 2 to 5.

[0070] Based on the ignition device provided in the above embodiments, the present utility model further provides a boiler, which includes: an ignition device;

[0071] The ignition device includes: a housing 1, an arc plasma generator 2, a pre-chamber 3, a microwave reaction ring 4, a microwave inducer, a pipeline 6, and a first central cylinder 7;

[0072] One end of the pipeline 6 is communicated with the feeding end of the housing 1 for conveying pulverized coal to the housing 1;

[0073] The pre-chamber 3 is arranged inside the housing 1;

[0074] The arc plasma generator 2 is arranged at the feeding end of the pre-chamber 3 for generating arc plasma to heat the pulverized coal in the pre-chamber 3;

[0075] The microwave reaction ring 4 is sleeved on the housing 1;

[0076] The microwave inducer is connected to the microwave reaction ring 4, and the microwave reaction ring 4 is used for feeding the microwave energy formed by the microwave inducer into the pre-chamber 3 and the first central cylinder 7;

[0077] The first end of the first central cylinder 7 is communicated with the discharging end of the pre-chamber 3, wherein the diameter of the first central cylinder 7 is larger than that of the pre-chamber 3.

[0078] In the embodiment of the present utility model, one end of the pipeline 6 is communicated with the feeding end of the housing 1, and pulverized coal is conveyed to the housing 1. The pre-chamber 3 is arranged inside the housing 1, and the arc plasma generator 2 is arranged at the feeding end of the pre-chamber 3, so as to heat the pulverized coal in the pre-chamber 3 by generating arc plasma. The microwave reaction ring 4 is sleeved on the housing 1, the microwave inducer is connected to the microwave reaction ring 4, and the microwave reaction ring 4 feeds the microwave energy formed by the microwave inducer into the pre-chamber 3 and the first central cylinder 7. The first end of the first central cylinder 7 is communicated with the discharging end of the pre-chamber 3, and the diameter of the first central cylinder 7 is larger than that of the pre-chamber 3. Through the above disclosed ignition device, when the pulverized coal is conveyed into the housing 1 through the pipeline 6, part of the pulverized coal enters the pre-chamber 3. At this time, the microwave reaction ring 4 feeds the microwave energy formed by the microwave inducer into the pre-chamber 3, which can enhance the plasma arc generated by the arc plasma generator 2 and preheat part of the pulverized coal at the same time. After the arc plasma is enhanced by the microwave energy, it can ignite the pulverized coal that is simultaneously preheated by the microwave energy, realizing ignition. Compared with the existing boiler ignition device, the present application can improve the ignition performance of difficult-to-burn coals such as inferior bituminous coal and lean coal through multi-point coupling, and realize the ignition of difficult-to-burn pulverized coal.

[0079] For the convenience of understanding the above solution, the following will be further introduced in combination with Figure 1 and Figure 2 for further introduction.

[0080] In the device for multi-point coupling ignition of microwave and arc plasma in the present utility model, the realization of its effect is divided into three stages:

[0081] The first stage: The microwave of the microwave reaction ring 4 acts on the conventional arc plasma. By feeding a small amount of microwave energy through the microwave reaction ring 4, the formed electromagnetic field achieves the purpose of enhancing the arc plasma core, improves the energy of the arc plasma, and enhances the heat treatment effect of the arc plasma on pulverized coal. In addition, the microwave can preheat the pulverized coal therein and also strengthen the reaction between the pulverized coal and the arc plasma.

[0082] The second stage: The heat treatment of pulverized coal by the arc plasma. Using the arc plasma enhanced by the microwave, part of the pulverized coal is heat-treated into a mixed fuel of volatile matter and coke, improving the fuel temperature and activity.

[0083] The third stage: The microwave acts on the high-temperature fuel gas flow after being treated by the arc plasma. Through microwave-induced heating, with semi-coke and volatile matter in the high-temperature fuel gas flow as absorbents, discharge of coke particles is realized and multiple high-temperature fire nuclei are formed, achieving multi-point ignition of the mixed fuel and successfully cultivating the initial flame and continuous propagation of the flame during ignition.

[0084] Through the mutual coupling of the above three stages, ignition of difficult-to-burn pulverized coal is finally realized.

[0085] Advantages of this application: Through the multi-point coupling of microwave - plasma - high-temperature mixed fuel, that is, the coupling of microwave with arc plasma and pulverized coal gas flow, the heat treatment of pulverized coal gas flow by arc plasma, and the coupling of microwave with high-temperature gas fuel after being heat-treated by arc plasma, multi-point coupling effect is realized, comprehensively improving the ignition performance of difficult-to-burn coal types, and finally realizing ignition of difficult-to-burn pulverized coal.

[0086] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present utility model. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present utility model. Therefore, the present utility model will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An ignition device, characterized in that, Comprising: A housing, an arc plasma generator, a pre-chamber, a microwave reaction ring, a microwave inducer, a pipeline, and a first central tube; One end of the pipeline is communicated with the feeding end of the housing for conveying pulverized coal to the housing; The pre-chamber is arranged inside the housing; The arc plasma generator is arranged at the feeding end of the pre-chamber for generating arc plasma to heat the pulverized coal in the pre-chamber; The microwave reaction ring is sleeved on the housing; The microwave inducer is connected with the microwave reaction ring, and the microwave reaction ring is used for feeding the microwave energy formed by the microwave inducer into the pre-chamber and the first central tube; The first end of the first central tube is communicated with the discharging end of the pre-chamber, wherein the diameter of the first central tube is larger than that of the pre-chamber.

2. The ignition device according to claim 1, characterized in that, The housing is of a cylindrical structure.

3. The ignition device according to claim 2, wherein The pre-chamber, the housing, and the first central tube are all coaxially arranged.

4. The ignition device according to claim 1, characterized in that, The microwave inducer comprises: a magnetron and a waveguide; The magnetron is connected with the microwave reaction ring through the waveguide.

5. The ignition device according to claim 1, characterized in that, The power range of the arc plasma generator is 5KW - 200kW.

6. The ignition device according to claim 1, characterized in that, The power range of the microwave inducer is 0.5KW - 70KW.

7. The ignition device according to claim 1, characterized in that, Further comprising: A second central tube; One end of the second central tube is communicated with the second end of the first central tube, wherein the diameter of the second central tube is larger than that of the first central tube.

8. The ignition device according to claim 7, characterized in that, The microwave reaction ring comprises: a first reaction ring and a second reaction ring; Both the first reaction ring and the second reaction ring are sleeved on the housing, wherein the first reaction ring is used for enhancing the plasma arc generated by the arc plasma generator and preheating the pulverized coal, and the second reaction ring is used for inducing and heating the high-temperature fuel gas flow in the first central tube and the second central tube.

9. The ignition device according to claim 7, characterized in that, The second central tube is coaxially arranged with the first central tube.

10. A boiler, characterized in that, Comprising the ignition device according to any one of claims 1 to 9.

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