Feeding device of circulating fluidized bed boiler

Abstract

The utility model discloses a feeding device of a circulating fluidized bed boiler, which relates to the technical field of circulating fluidized bed boilers and comprises a feeding pipe and a pneumatic feeding component, and the pneumatic feeding component is used for providing conveying power for fuel particles in the feeding pipe. The pneumatic feeding assembly comprises an outer connecting pipe, an air inlet pipe, a sliding sleeve, a conical plug and a discharging port. High-pressure air is conveyed into the outer connecting pipe through the air inlet pipe to push the sliding sleeve, the conical plug and the discharging port to horizontally move so that the discharging port can communicate with the feeding pipe, and therefore a conveying channel of the fuel particles can be communicated. By arranging the pneumatic feeding assembly and the central gas pipe, efficient feeding of fuel particles can be achieved, and when the air pressure in the boiler is increased sharply due to entering and detonation of the fuel particles and is larger than the air pressure in the outer connecting pipe, the conical plug can be pushed by the air pressure in the boiler to reset to block the outer connecting pipe; air in a boiler is prevented from making contact with fuel particles in a feeding pipe, and feeding operation safety is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of circulating fluidized bed boiler technology, specifically a feeding device for a circulating fluidized bed boiler. Background Technology

[0002] Circulating fluidized bed boilers are a high-efficiency, low-pollution combustion technology widely used in coal-fired power generation, industrial heating, and waste treatment. Their core characteristic is that fuel is burned in a fluidized state, and efficient heat transfer and pollution control are achieved through a material circulation system. The working principle is as follows:

[0003] Primary air is introduced into the bottom of the boiler, which suspends the bed material (quartz sand, limestone, etc.) and fuel particles in the furnace, forming a fluid-like state. During this process, the fuel mixes with the air and burns. The combustion temperature is usually controlled at 50–950℃ (lower than pulverized coal boilers), which effectively reduces the formation of thermal NOx.

[0004] In order to ensure smooth fuel feeding, existing circulating fluidized bed boilers crush fuel into smaller particles. When these smaller fuel particles enter the furnace, they can explode, causing a sudden increase in furnace pressure and potentially leading to high-temperature flue gas backflow into the feed pipe. To avoid this, a circulating fluidized bed boiler feeding device is provided. Utility Model Content

[0005] The purpose of this utility model is to provide a feeding device for a circulating fluidized bed boiler in order to solve the problems mentioned above.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a circulating fluidized bed boiler feeding device, including a feeding pipe, wherein a pneumatic feeding assembly is provided on the outside of the outlet of the feeding pipe, and the pneumatic feeding assembly is used to provide conveying power for fuel particles in the feeding pipe;

[0007] The pneumatic feeding assembly includes an external connecting pipe, an air inlet pipe, a sliding sleeve, a conical plug, and a discharge port;

[0008] The external connecting pipe is fixed to the outside of the feed pipe outlet end, and the front end of the external connecting pipe is fixedly connected to the boiler.

[0009] The air inlet pipe is fixed to the outer side of the end of the external connecting pipe away from the boiler and is in communication with the inner cavity of the external connecting pipe;

[0010] The sliding sleeve is distributed inside the outer connecting pipe and slidably sleeved on the outside of the feeding pipe. The conical plug is fixed to one end of the sliding sleeve and distributed at the front end of the feeding pipe. The discharge port is circumferentially opened on the outer periphery of the sliding sleeve and communicates with the inner cavity of the sliding sleeve.

[0011] High-pressure air is supplied to the external connecting pipe through the air inlet pipe to push the sliding sleeve, conical plug, and discharge port to move horizontally, so that the discharge port is connected to the feed pipe, thereby realizing the connection of the fuel particle conveying channel.

[0012] As a further improvement of this utility model: a tapered expansion hole is formed at the position of the external connecting pipe near the tapered plug, and the tapered surface of the tapered plug fits into the tapered expansion hole to achieve the sealing of the external connecting pipe.

[0013] As a further improvement of this utility model: a fixing ring block is fixed on the outer side of the front end of the feed pipe, and the outer wall of the fixing ring block matches the diameter of the inner wall of the sliding sleeve.

[0014] As a further embodiment of this utility model: the conical plug is located on the inner side of the sliding sleeve and forms a conical protrusion, the conical protrusion being fitted with the front end of the feed pipe to achieve front end sealing of the feed pipe.

[0015] As a further embodiment of this utility model: a central air pipe is provided at one end of the feeding pipe, which extends horizontally into the interior of the feeding pipe. One end of the central air pipe is close to the front end of the feeding pipe and does not contact the conical protrusion of the conical plug.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] By setting up a pneumatic feeding assembly and a central air pipe, efficient feeding of fuel particles can be achieved. When the gas pressure inside the boiler increases dramatically due to the entry and deflagration of fuel particles, and exceeds the gas pressure inside the external connecting pipe, the conical plug will be reset and block the external connecting pipe under the push of the gas pressure inside the boiler. This is to prevent the air inside the boiler from contacting the fuel particles inside the feeding pipe and to ensure safe feeding operation. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a cross-sectional view of the structure of the present invention when the internal air pressure of the external connecting pipe is greater than the internal air pressure of the boiler;

[0020] Figure 3 This is a cross-sectional view of the structure of the external connecting pipe of this utility model when the internal air pressure is lower than the internal air pressure of the boiler.

[0021] In the diagram: 1. Feed pipe; 2. Pneumatic feeding assembly; 201. External connecting pipe; 202. Air inlet pipe; 203. Conical expansion hole; 204. Sliding sleeve; 205. Conical plug; 206. Discharge port; 3. Fixed ring block; 4. Central air pipe. Detailed Implementation

[0022] 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.

[0023] Please see Figures 1-3 In this embodiment of the utility model, a circulating fluidized bed boiler feeding device includes a feeding pipe 1, and a pneumatic feeding assembly 2 is provided on the outside of the outlet of the feeding pipe 1. The pneumatic feeding assembly 2 is used to provide conveying power for the fuel particles in the feeding pipe 1.

[0024] The pneumatic feeding assembly 2 includes an external connecting pipe 201, an air inlet pipe 202, a sliding sleeve 204, a conical plug 205, and a discharge port 206;

[0025] The external connecting pipe 201 is fixed to the outside of the discharge end of the feed pipe 1, and the front end of the external connecting pipe 201 is fixedly connected to the boiler.

[0026] The air inlet pipe 202 is fixed to the outer side of the end of the external connecting pipe 201 away from the boiler and is in communication with the inner cavity of the external connecting pipe 201;

[0027] The sliding sleeve 204 is distributed inside the outer connecting pipe 201 and slidably sleeved on the outside of the feeding pipe 1. The conical plug 205 is fixed at one end of the sliding sleeve 204 and distributed at the front end of the feeding pipe 1. The discharge port 206 is circumferentially opened on the outer periphery of the sliding sleeve 204 and communicates with the inner cavity of the sliding sleeve 204.

[0028] High-pressure air is supplied to the inside of the external connecting pipe 201 through the air inlet pipe 202 to push the sliding sleeve 204, the conical plug 205, and the discharge port 206 to move horizontally, so that the discharge port 206 is connected to the feed pipe 1, thereby realizing the opening of the fuel particle conveying channel.

[0029] A tapered enlarged hole 203 is formed at the position of the external connecting pipe 201 near the tapered plug 205. The tapered surface of the tapered plug 205 fits into the tapered enlarged hole 203 to achieve the sealing of the external connecting pipe 201.

[0030] A central air pipe 4 is provided at one end of the feed pipe 1, which extends horizontally into the interior of the feed pipe 1.

[0031] In this embodiment, it should be noted that the front end of the external connecting pipe 201 is fixed to the circulating fluidized bed boiler and communicates with the inner cavity of the circulating fluidized bed boiler, and the feed pipe 1 is connected to the external feed conveying pipeline.

[0032] When no high-pressure air is input into the air inlet pipe 202, the air pressure inside the external connecting pipe 201 is lower than the air pressure inside the boiler. At this time, the conical plug 205 is squeezed by the air pressure from inside the boiler and fits tightly against the conical surface of the conical expansion hole 203, thereby sealing the external connecting pipe 201.

[0033] When fuel pellets are being fed, the air supply lines of the air inlet pipe 202 and the central air pipe 4 are simultaneously connected, so that high-pressure air is delivered to the air inlet pipe 202 and the central air pipe 4. At this time, the high-pressure air entering the outer connecting pipe 201 through the air inlet pipe 202 increases the air pressure inside the outer connecting pipe 201. When the air pressure inside the outer connecting pipe 201 is greater than the air pressure inside the boiler, the air inside the outer connecting pipe 201 will push the conical plug 205 to move towards the boiler. This not only creates a channel between the conical plug 205 and the conical expansion hole 203, but also causes the conical plug 205 to drive the sliding sleeve 204 to move, so that the front end of the feed pipe 1 and the discharge port 206 are connected to each other.

[0034] At the same time, the central air pipe 4 supplies air to the middle of the front end of the feed pipe 1, so that the fuel particles inside the feed pipe 1 quickly approach the outlet 206. Meanwhile, the airflow flowing along the channel between the conical plug 205 and the conical expansion hole 203 forms a suction at the outlet 206 (Bernoulli principle), so that the fuel particles can be quickly transported into the boiler.

[0035] When the pressure inside the boiler increases dramatically due to the entry and deflagration of fuel particles, and exceeds the pressure inside the external connecting pipe 201, the conical plug 205 will reset and block the external connecting pipe 201 to prevent the air inside the boiler from contacting the fuel particles inside the feed pipe 1, thus ensuring safe feeding operation.

[0036] Please refer to this carefully. Figures 2-3 A fixing ring 3 is fixed on the outer side of the front end of the feed pipe 1, and the outer wall of the fixing ring 3 matches the inner wall diameter of the sliding sleeve 204.

[0037] In this embodiment, the fixed ring block 3 provides guidance and limitation for the movement of the sliding sleeve 204.

[0038] Please refer to this carefully. Figures 2-3 The conical plug 205 is located inside the sliding sleeve 204 and has a conical protrusion. The conical protrusion fits against the front end of the feed pipe 1 to achieve front end sealing of the feed pipe 1.

[0039] One end of the central air tube 4 is close to the front end of the feed tube 1 and does not contact the conical protrusion of the conical plug 205.

[0040] In this embodiment: when the conical plug 205 and the conical expansion hole 203 are in contact, the conical protrusion blocks the front end of the feed pipe 1. At the same time, when feeding, the fuel particles output from the feed pipe 1 collide with the conical protrusion and can be scattered and output outward through the discharge port 206, thereby improving the feeding dispersion of fuel particles.

[0041] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A feeding device for a circulating fluidized bed boiler, comprising a feeding pipe (1), characterized in that, A pneumatic feeding assembly (2) is provided on the outside of the discharge port of the feeding pipe (1). The pneumatic feeding assembly (2) is used to provide conveying power for the fuel particles in the feeding pipe (1). The pneumatic feeding assembly (2) includes an external connecting pipe (201), an air inlet pipe (202), a sliding sleeve (204), a conical plug (205), and a discharge port (206). The external connecting pipe (201) is fixed to the outside of the discharge end of the feed pipe (1), and the front end of the external connecting pipe (201) is fixedly connected to the boiler; The air inlet pipe (202) is fixed to the outer side of the end of the external connecting pipe (201) away from the boiler and is in communication with the inner cavity of the external connecting pipe (201); The sliding sleeve (204) is distributed inside the outer connecting pipe (201) and slidably sleeved on the outside of the feeding pipe (1). The conical plug (205) is fixed at one end of the sliding sleeve (204) and distributed at the front end of the feeding pipe (1). The discharge port (206) is circumferentially opened on the outer periphery of the sliding sleeve (204) and communicates with the inner cavity of the sliding sleeve (204). High-pressure air is supplied to the inside of the external connecting pipe (201) through the air inlet pipe (202) to push the sliding sleeve (204), the cone plug (205), and the discharge port (206) to move horizontally so that the discharge port (206) is connected to the feed pipe (1), thereby realizing the connection of the fuel particle conveying channel.

2. The circulating fluidized bed boiler feeding device according to claim 1, characterized in that, The external connecting pipe (201) has a tapered enlarged hole (203) formed near the tapered plug (205). The tapered surface of the tapered plug (205) fits into the tapered enlarged hole (203) to achieve the sealing of the external connecting pipe (201).

3. The circulating fluidized bed boiler feeding device according to claim 1, characterized in that, A fixing ring block (3) is fixed on the outer side of the front end of the feed pipe (1), and the outer wall of the fixing ring block (3) matches the inner wall diameter of the sliding sleeve (204).

4. The circulating fluidized bed boiler feeding device according to claim 1, characterized in that, The conical plug (205) is located inside the sliding sleeve (204) and forms a conical protrusion. The conical protrusion fits against the front end of the feed pipe (1) to achieve front end sealing of the feed pipe (1).

5. A circulating fluidized bed boiler feeding device according to claim 4, characterized in that, One end of the feed pipe (1) is provided with a central air pipe (4) that extends horizontally into the interior of the feed pipe (1). One end of the central air pipe (4) is close to the front end of the feed pipe (1) and does not contact the conical protrusion of the conical plug (205).

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