Circulating fluidized bed boiler using ammonium sulfate as denitration reagent

Abstract

The utility model relates to a circulating fluidized bed boiler using ammonium sulfate as a denitration reagent, which comprises a boiler main body and a cyclone separator, the upper sides of the boiler main body and the cyclone separator are connected with a horizontal flue, and the lower side of the cyclone separator is connected with a material return device leading to the boiler main body. The boiler is characterized in that a coal falling pipe is connected to the lower side of the boiler body, a first atomization spray gun is arranged on the portion, on the upper side of the coal falling pipe, of the boiler body, a second atomization spray gun is arranged on the horizontal flue, and the second atomization spray gun is used for conducting reverse spraying in the flue gas flowing direction. According to the utility model, the second atomizing spray gun performs reverse spraying towards the flowing direction of the flue gas, so that the retention time of liquid drops in the flue gas is longer, the contact time of the liquid drops and the flue gas is prolonged, the liquid drops can be more uniformly mixed and distributed in the flue gas, and the denitration efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of boilers, in particular to a circulating fluidized bed boiler using ammonium sulfate as a denitration reagent. Background Art

[0002] Circulating fluidized bed boilers are widely used in the industrial and power generation fields due to their efficient combustion and low pollutant emissions. However, when dealing with industrial solid wastes containing high calcium components, traditional denitration processes (such as selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR)) face challenges. The high calcium components can lead to a reduction in denitration efficiency, thus affecting the compliance with emission standards.

[0003] When dealing with high calcium industrial solid wastes, due to the large amount of CaO components in the solid wastes, these components can catalyze the reduction agent NH in the denitration system 3 to be oxidized to NO, thereby reducing the denitration efficiency. When traditional denitration processes are used to deal with such solid wastes, they often cannot achieve the ideal denitration effect, resulting in the over-standard emission of NOx.

[0004] Currently, commonly used denitration reagents such as urea and ammonia water have poor effects when dealing with high calcium industrial solid wastes. In a high calcium industrial solid waste incineration treatment process with the patent application number CN202310036010.X, a method of using ammonium sulfate as a denitration reagent is mentioned. It sprays ammonium sulfate into the boiler from the lower part of the boiler (below the secondary air inlet) and the horizontal flue between the boiler and the cyclone separator through an atomizing spray gun, thereby improving the denitration efficiency, reducing NOx emissions, and meeting environmental protection requirements.

[0005] Among them, when spraying liquid ammonium sulfate solution into the horizontal flue, due to the short residence time of the flue gas in the horizontal flue, the sprayed liquid ammonium sulfate solution may have a problem of low mixing efficiency with the flue gas, making it difficult to ensure that the liquid ammonium sulfate can be evenly dispersed and fully mixed with the flue gas. In view of the above technical problems, this application makes improvements. Summary of the Utility Model

[0006] The utility model provides a circulating fluidized bed boiler using ammonium sulfate as a denitration reagent, which solves the above problems existing in the prior art during use.

[0007] The technical solution of the utility model is realized as follows: A circulating fluidized bed boiler using ammonium sulfate as a denitration reagent includes a boiler main body and a cyclone separator. A horizontal flue is connected to the upper sides of the boiler main body and the cyclone separator. A return feeder leading to the boiler main body is connected to the lower side of the cyclone separator. A coal dropping pipe is connected to the lower side of the boiler main body. A first atomizing spray gun is provided above the coal dropping pipe on the boiler main body. A second atomizing spray gun is provided on the horizontal flue, and the second atomizing spray gun is used for reverse spraying towards the flue gas flow direction.

[0008] Preferably, an adjusting mechanism for adjusting the spraying angle of the second atomizing spray gun is provided on the horizontal flue.

[0009] Preferably, the second atomizing spray gun includes a gun body, a nozzle, an input pipe, and a control tail. The nozzle is connected to the gun body and faces the side of the boiler main body. The control tail is fixedly connected to one end of the gun body away from the nozzle. One end of the input pipe is fixedly connected with a connecting sphere, and the connecting sphere is rotatably fitted on the gun body. A solution chamber leading to the nozzle is provided in the gun body. A high-pressure flow channel is provided on the input pipe, and the high-pressure flow channel penetrates through the connecting sphere and is connected to the solution chamber. The input pipe is fixedly connected to the side wall of the horizontal flue, and one end of the input pipe away from the connecting sphere penetrates through the side wall of the horizontal flue. The adjusting mechanism is connected to the control tail.

[0010] Preferably, the adjusting mechanism includes a driving rod and a telescopic cylinder. The telescopic cylinder is fixedly connected to the outer side wall of the horizontal flue. A sliding hole is provided on the side wall of the horizontal flue. The telescopic shaft of the telescopic cylinder passes through the sliding hole and is hinged to one end of the driving rod. The other end of the driving rod is hinged to the control tail.

[0011] Preferably, at least two second atomizing spray guns are circumferentially arranged on the horizontal flue.

[0012] Preferably, a secondary air inlet is provided in the middle of the boiler main body, and the first atomizing spray gun is located between the secondary air inlet and the coal dropping pipe.

[0013] Preferably, a tail flue is connected to the upper end of the cyclone separator.

[0014] In summary, the beneficial effects of the present utility model are as follows:

[0015] 1. The second atomizing spray gun sprays reversely in the direction of the flue gas flow, which makes the residence time of the liquid droplets in the flue gas longer, thereby increasing the contact time between the liquid droplets and the flue gas, and also helps the liquid droplets to be more evenly mixed and distributed in the flue gas, improving the denitration efficiency.

[0016] 2. The spraying angle of the second atomizing spray gun can be adjusted, so that the present utility model can adjust the angle according to factors such as the flue gas temperature, flow velocity, and the size of the liquid droplets sprayed by the second atomizing spray gun, thereby better improving the mixing efficiency of ammonium sulfate and the flue gas. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1 Schematic diagram of the overall structure of the present invention;

[0019] Figure 2 For Figure 1 Partial enlarged schematic diagram of the horizontal flue part in

[0020] Figure 3 Stereoscopic structure schematic diagram of the second atomizing spray gun part in the present invention;

[0021] Figure 4 For Figure 3 Schematic diagram of the structure after removing the nozzle;

[0022] Figure 5 For Figure 4 Cross-sectional structure schematic diagram of

[0023] In the figure: 1. Boiler main body; 11. Secondary air inlet; 2. Cyclone separator; 3. Horizontal flue; 31. Sliding hole; 4. Loop seal; 5. Coal dropping pipe; 6. First atomizing spray gun; 7. Second atomizing spray gun; 71. Gun body; 711. Solution chamber; 72. Nozzle; 73. Input pipe; 731. Connecting sphere; 732. High-pressure flow channel; 74. Control tail; 81. Driving rod; 82. Telescopic cylinder; 9. Tail flue. Specific embodiments

[0024] The following will combine the attached Figures 1-5 in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all 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.

[0025] Embodiment:

[0026] Such as Figures 1 to 5As shown in the figure, the utility model discloses a circulating fluidized bed boiler using ammonium sulfate as a denitration reagent, which includes a boiler main body 1 and a cyclone separator 2. A horizontal flue 3 is connected to the upper sides of the boiler main body 1 and the cyclone separator 2. A return feeder 4 leading to the boiler main body 1 is connected to the lower side of the cyclone separator 2. A coal dropping pipe 5 is connected to the lower side of the boiler main body 1. Among them, a first atomizing spray gun 6 is provided on the upper side of the coal dropping pipe 5 of the boiler main body 1. In addition, a second atomizing spray gun 7 is provided on the horizontal flue 3, and the second atomizing spray gun 7 is used for reverse spraying towards the direction of flue gas flow.

[0027] When the utility model is in use, ammonium sulfate can be input into the furnace alone in a solid state or alone in a liquid state, or it can be input together in a combination of solid and liquid states. The input method of solid ammonium sulfate is: mixing solid ammonium sulfate with coal and entering the boiler main body 1 through the coal dropping pipe 5. The input method of liquid ammonium sulfate is: spraying it from the first atomizing spray gun 6 and / or the second atomizing spray gun 7. In order to increase the contact time between the ammonium sulfate droplets sprayed into the horizontal flue 3 by the second atomizing spray gun 7 and the flue gas and improve the mixing efficiency, the second atomizing spray gun 7 sprays in the reverse direction of the flue gas flow. Because the spraying speed of the ammonium sulfate solution sprayed in the reverse direction can offset a part of the flow speed of the flue gas, the residence time of the liquid ammonium sulfate solution in the flue gas is longer, and the contact time with the flue gas also increases accordingly. Increasing the contact time between the liquid ammonium sulfate solution and the flue gas also helps the droplets to be more evenly distributed in the flue gas and improves the denitration efficiency.

[0028] Furthermore, an adjusting mechanism for adjusting the spraying angle of the second atomizing spray gun 7 is provided on the horizontal flue 3. Since factors such as the temperature, flow speed of the flue gas, and the size of the sprayed droplets may affect the mixing speed of the flue gas and ammonium sulfate, users can adjust the spraying angle of the second atomizing spray gun 7 according to the specific use.

[0029] Specifically, the second atomizing spray gun 7 includes a gun body 71, a nozzle 72, an input pipe 73 and a control tail 74. The nozzle 72 is connected to the gun body 71 and faces the side of the boiler main body 1. The nozzle 72 is preferably a vortex atomizing nozzle. The vortex atomizing nozzle causes the liquid ammonium sulfate solution to form a vortex inside the nozzle. When the liquid leaves the nozzle, the action of the vortex causes the liquid to break into fine droplets. Since the vortex atomizing nozzle is a prior art, its specific structure will not be described in detail here. In addition, the control tail 74 is fixedly connected to one end of the gun body 71 away from the nozzle 72. One end of the input pipe 73 is fixedly connected with a connecting sphere 731, and the connecting sphere 731 is rotationally fitted on the gun body 71. A solution chamber 711 leading to the nozzle 72 is provided in the gun body 71. A high-pressure flow channel 732 is provided on the input pipe 73, and the high-pressure flow channel 732 penetrates through the connecting sphere 731 and is connected to the solution chamber 711. The input pipe 73 is fixedly connected to the side wall of the horizontal flue 3, and one end of the input pipe 73 away from the connecting sphere 731 penetrates through the side wall of the horizontal flue 3. The end of the input pipe 73 penetrating through the side wall of the horizontal flue 3 is externally connected to a pump body for inputting ammonium sulfate, so as to transport ammonium sulfate to the second atomizing spray gun 7 and spray it out from the nozzle 72. In addition, the adjusting mechanism is connected to the control tail 74. Specifically, the adjusting mechanism includes a driving rod 81 and a telescopic cylinder 82. The telescopic cylinder 82 is fixedly connected to the outer side wall of the horizontal flue 3. A sliding hole 31 is provided on the side wall of the horizontal flue 3. The telescopic shaft of the telescopic cylinder 82 passes through the sliding hole 31 and is hinged to one end of the driving rod 81. The other end of the driving rod 81 is hinged to the control tail 74. In this way, when the telescopic cylinder 82 controls the telescopic shaft to move linearly, the control tail 74 can be driven by the driving rod 81, so that the gun body 71 rotates at an angle with the connecting sphere 731 of the input pipe 73 as the center, thereby realizing the angle adjustment of the second atomizing spray gun 7 within a certain range.

[0030] Furthermore, at least two second atomizing spray guns 7 are circumferentially arranged on the horizontal flue 3. The arrangement of multiple second atomizing spray guns 7 can improve the mixing efficiency of ammonium sulfate and flue gas.

[0031] In the present utility model, a secondary air inlet 11 is provided in the middle of the boiler main body 1, and the first atomizing spray gun 6 is located between the secondary air inlet 11 and the coal dropping pipe 5. Since the temperature below the secondary air inlet 11 is relatively high, it helps the liquid ammonium sulfate solution to quickly evaporate and atomize into fine droplets, thereby improving the denitration efficiency. And there is usually a strong turbulence below the secondary air inlet 11, which helps the liquid ammonium sulfate solution to be fully mixed with the flue gas and further improves the denitration effect.

[0032] In the present utility model, a tail flue 9 is connected to the upper end of the cyclone separator 2. The tail flue 9 is used to extend the residence time of the flue gas in the system, thereby increasing the contact time between the liquid ammonium sulfate solution and the flue gas and improving the denitration efficiency.

[0033] It should be noted that the terms pointed out by the present utility model, such as "front", "rear", "vertical", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the protection scope of the present utility model.

[0034] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A circulating fluidized bed boiler using ammonium sulfate as a denitrification agent, comprising a boiler body and a cyclone separator, wherein the boiler body and the upper side of the cyclone separator are connected with a horizontal flue, and the lower side of the cyclone separator is connected with a return device leading to the boiler body, characterized in that: A coal drop pipe is connected to the lower side of the boiler body, a first atomizing spray gun is arranged on the upper side of the coal drop pipe, and a second atomizing spray gun is arranged on the horizontal flue, and the second atomizing spray gun is used for reverse spraying toward the flue gas flow direction.

2. A circulating fluidized bed boiler using ammonium sulfate as a denitrification agent according to claim 1, characterized in that: The horizontal flue is provided with an adjusting mechanism for adjusting the spray angle of the second atomizing spray gun.

3. A circulating fluidized bed boiler using ammonium sulfate as a denitrification agent according to claim 2, characterized in that: The second atomizing spray gun includes a gun body, a nozzle, an input pipe and a control tail. The nozzle is connected to the gun body and faces one side of the boiler body. The control tail is fixedly connected to the end of the gun body away from the nozzle. A connecting ball is fixedly connected to one end of the input pipe, and the connecting ball is rotatably fitted on the gun body. A solution cavity leading to the nozzle is provided in the gun body. A high-pressure flow channel is provided on the input pipe, and the high-pressure flow channel passes through the connecting ball and is connected with the solution cavity. The input pipe is fixedly connected to the side wall of the horizontal flue, and the end of the input pipe away from the connecting ball penetrates the side wall of the horizontal flue. The adjustment mechanism is connected to the control tail.

4. A circulating fluidized bed boiler using ammonium sulfate as a denitrification agent according to claim 3, characterized in that: The adjustment mechanism includes a driving rod and a telescopic cylinder, the telescopic cylinder is fixedly connected to the outer side wall of the horizontal flue, a sliding hole is opened on the side wall of the horizontal flue, the telescopic shaft of the telescopic cylinder passes through the sliding hole and is hinged to one end of the driving rod, and the other end of the driving rod is hinged to the control tail.

5. A circulating fluidized bed boiler using ammonium sulfate as a denitration agent according to claim 1 or 2, characterized in that: At least two second atomizing spray guns are circumferentially arranged on the horizontal flue.

6. A circulating fluidized bed boiler using ammonium sulfate as a denitrification agent according to claim 1, characterized in that: A secondary air port is provided in the middle of the boiler body, and the first atomizing spray gun is located between the secondary air port and the coal dropping pipe.

7. The circulating fluidized bed boiler using ammonium sulfate as a denitrification agent according to claim 1, characterized in that: The upper end of the cyclone separator is connected with a tail flue.

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