A cyclone bed combustion device suitable for coarse particle fuel

Abstract

The application discloses a cyclone bed combustion device suitable for coarse particle diameter particle fuel and belongs to the technical field of thermal combustion power generation. The device comprises a base, a rotating flow channel, a feeding system, a combustion chamber, a slag discharge port, a heat exchange chamber, a horizontal flue and a cyclone separator. The bottom center of the combustion chamber is internally provided with a temperature adjusting fuel channel. A heat reflection arch is connected above the temperature adjusting fuel channel. A plurality of air supply nozzles are arranged on the heat reflection arch. The feeding system is communicated with the bottom of the combustion chamber through the rotating flow channel. A primary air nozzle and a secondary air nozzle are arranged on the inner wall of the rotating flow channel. The design of the cyclone bed combustion device is suitable for coarse particle diameter and has the advantages of timely heating of combustible materials, low energy consumption and no sintering. In addition, the base and the rotating flow channel of the device are further provided with a fixed air chamber. The design of the secondary air of the rotating flow channel and the fixed air chamber can well drive the rotation, pyrolysis and combustion of the fuel, and further improves the utilization rate of the fuel.

Description

Technical Field

[0001] This invention belongs to the field of thermal combustion power generation technology, specifically relating to a cyclone bed combustion device suitable for coarse-diameter particulate fuel. Background Technology

[0002] Currently, the main combustion devices for coarse particulate fuels larger than 2 micrometers (such as low-quality fuels, biomass, sludge, garbage, etc.) are circulating fluidized bed boilers, rotary kilns, grate furnaces, chain grate furnaces, and circulating fluidized bed furnaces.

[0003] The characteristics of grate furnaces burning waste include large variations in fuel calorific value and difficulty in accurately predicting the amount of air required for combustion. Therefore, during combustion, the excess air coefficient in the flue gas is high, the excess oxygen concentration is high, combustion stability is poor, and a large amount of auxiliary fuel is needed to control the furnace temperature. Horizontal axis rotary kilns mainly rely on mechanical rotation to move the bed material forward. The rotating body has a large mass, a small adjustable temperature range, and the reaction rate is difficult to control. Pulverized coal cyclone furnaces are less commonly used, mainly for the combustion of fine pulverized coal particles, where the combustion occurs on the wall surface, resulting in higher reaction temperatures that are not conducive to energy conservation.

[0004] Unlike the aforementioned processes, circulating fluidized bed (CFB) combustion technology offers stronger combustion stability and requires relatively lower temperatures and energy consumption. However, the bed material in a CFB undergoes repeated sintering, ranging from micrometers to tens of millimeters. Combined with the large fuel particle size, this results in a significant pressure drop during fluidized bed combustion, high primary air energy consumption, and difficulty in uniformly distributing the feed within the bed. This leads to unburned fuel being discharged with the slag, causing fuel loss. Furthermore, for the combustion of biomass and waste, it easily causes localized agglomeration and overheating. Current CFB technology suffers from problems such as high particle position uncertainty during large particle fluidization, ash sintering, high energy consumption, burnout loss, and the inability of circulating ash to promptly heat combustibles.

[0005] Therefore, it is essential to invent a new bed structure to address the problems existing in various coarse particle combustion devices and meet the need for clean and efficient combustion. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a cyclone bed combustion device suitable for coarse-diameter particulate fuels. Due to its special rotating flow channel design and flue design, it enables coarse-particle fuel combustion to become more stable and reliable, with high combustion efficiency and less sintering.

[0007] According to one aspect of the present invention, a cyclone bed combustion device suitable for coarse-diameter particulate fuel is provided. The cyclone bed combustion device includes a base, a combustion chamber, a rotating flow channel, a feeding system, a slag discharge port, a heat exchange chamber, a horizontal flue, and a cyclone separator. The combustion chamber is connected to the base, and the heat exchange chamber and the horizontal flue are connected sequentially above the combustion chamber. Cyclone separators are connected to both sides of the horizontal flue. The cyclone separators are connected to the opening at the top of the combustion chamber through pipelines to form a return circuit.

[0008] The combustion chamber has a temperature regulating air duct and a fuel passage at the bottom center. A heat reflector arch is connected above the temperature regulating fuel passage. The heat reflector arch has multiple air supply nozzles. The slag discharge port is located at the bottom of the combustion chamber.

[0009] The feeding system has a feed inlet and is connected to the bottom of the combustion chamber through a rotating channel. The inner wall of the rotating channel is a film cooling wall, and the inner wall of the rotating channel has primary air and secondary air nozzles.

[0010] According to one embodiment of the present invention, the outer wall of the cyclone bed combustion device is an integral three-dimensional conical structure, which is filled with water-cooled pipes and refractory mortar; a rotating shaft is provided at the center of the cone top of the three-dimensional cone, and the rotating shaft has a hollow cooling water channel inside, and the rotating shaft is rotatably and sealedly connected to the base; the top outer wall of the combustion chamber serves as the cone opening of the three-dimensional cone, and the cone opening is provided with multiple L-shaped return ports corresponding to the cyclone separator at intervals in the circumferential direction.

[0011] According to one embodiment of the present invention, the transverse cross-section of the rotating flow channel is either a semi-circular cross-section or a circular cross-section; or it is a cross-section with semi-circles on the left and right sides and a rectangle in the middle.

[0012] According to one embodiment of the present invention, a fixed air chamber is further provided between the base and the rotating flow channel. The fixed air chamber has a double-layer structure of an inner layer and an outer layer, wherein the inner layer is a flue gas layer and the outer layer is an air layer, or the inner layer is an air layer and the outer layer is a flue gas layer. The gas in the fixed air chamber enters the primary air and secondary air nozzles through the air duct on the back of the cone.

[0013] According to one embodiment of the present invention, the inner conical surface of the three-dimensional cone is a spiral channel, and multiple nozzles are arranged in the spiral channel to ensure the oxygen or air required for particle combustion, while providing the power for particle rotation and forward movement.

[0014] According to one embodiment of the present invention, the feed inlet of the feeding system is rotatably connected to the rotary flow channel.

[0015] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages:

[0016] (1) The swirl bed combustion device designed in this invention has the advantages of complete particle combustion, timely heating of combustibles, low energy consumption and no sintering for coarse particle size fuels.

[0017] (2) The rotating flow channel and secondary air intake design of the present invention can effectively promote the gasification, pyrolysis and combustion of fuel, which is conducive to the separation of volatiles, fixed carbon and ash in a time sequence, improve the utilization rate of effective fuel and reduce polluting flue gas. Attached Figure Description

[0018] Appendix Figure 1 This is a schematic diagram of the cyclone bed boiler structure in Embodiment 1 of the present invention.

[0019] Appendix Figure 2 This is a schematic diagram of the AA cross-section of the rotating flow channel in Embodiment 1 of the present invention.

[0020] Appendix Figure 3 This is a cross-sectional schematic diagram of the rotating flow channel in Embodiment 2 of the present invention.

[0021] The attached diagram is labeled as follows: 1 Combustion chamber, 2 Rotary flow channel, 3 Feeding system, 4 Fixed air chamber, 5 Slag discharge port, 6 Temperature regulating air duct and fuel passage, 7 Heat reflector arch, 8 Heat exchange chamber, 9 Horizontal flue, 10 Cyclone separator, 11 Primary and secondary air nozzles, 12 Membrane cooling wall. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0023] Example 1

[0024] like Figure 1 As shown, a cyclone bed combustion device suitable for coarse-diameter particulate fuel is disclosed. The cyclone bed combustion device includes a base, a combustion chamber 1, a rotating channel 2, a feeding system 3, a slag discharge port 5, a heat exchange chamber 8, a horizontal flue 9, and a cyclone separator 10. The combustion chamber 1 is connected to the base. The heat exchange chamber 8 and the horizontal flue 9 are connected sequentially above the combustion chamber 1. Cyclone separators 10 are connected to both sides of the horizontal flue 9. The cyclone separators 10 are connected to the opening at the top of the combustion chamber 1 through pipelines to form a return circuit.

[0025] The combustion chamber 1 has a temperature regulating air duct and a fuel passage 6 at the bottom center. A heat reflector arch 7 is connected above the temperature regulating air duct and the fuel passage 6. The heat reflector arch 7 has multiple air supply nozzles. The slag discharge port is located at the bottom of the combustion chamber 1.

[0026] The feeding system 3 has a feed inlet, and the feeding system 3 is connected to the bottom of the combustion chamber 1 through a rotating channel 2. The transverse cross-section of the rotating channel 2 is semi-circular or circular (e.g., Figure 2 As shown), the inner wall of the rotating flow channel 2 is a film cooling wall 12, and the inner wall of the rotating flow channel has primary air and secondary air nozzles 11 (as shown). Figure 2 (as shown);

[0027] The outer wall of the cyclone bed combustion device is a three-dimensional conical structure, which is filled with water-cooled pipes and refractory mortar. A rotating shaft is set at the center of the cone top of the three-dimensional cone, and the rotating shaft has a hollow cooling water channel inside. The rotating shaft is rotatably and sealed to the base. The top outer wall of the combustion chamber 1 serves as the cone opening of the three-dimensional cone, and the cone opening has two L-shaped return ports corresponding to the cyclone separator 10 at intervals in the circumferential direction.

[0028] The inner conical surface of the cyclone bed combustion device is a spiral channel. During the combustion process, the fuel and ash continuously pyrolyze, gasify and burn along the channel, and the generated ash enters the slag discharge port. Multiple nozzles are arranged in the spiral channel to ensure the oxygen or air required for particle combustion, while providing the power for particle rotation and forward movement.

[0029] The base and the rotating flow channel 2 are further provided with a fixed air chamber 4. The fixed air chamber 4 has a double-layer structure with an inner layer and an outer layer, wherein the inner layer is a flue gas layer and the outer layer is an air layer. The gas in the fixed air chamber 4 enters the primary air and secondary air nozzles 11 through the air duct on the back of the cone.

[0030] Example 2

[0031] The difference from Example 1 is that, as Figure 3 As shown, the transverse cross-sectional shape of its rotating flow channel 2 is a rectangular conical surface with semicircles on both the left and right sides. Compared with embodiment 1, due to the increase in cross-sectional area, it is suitable for use in larger capacity boilers.

[0032] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cyclone combustor, characterized by, The cyclone bed combustion device comprises a base, a combustion chamber (1), a rotating flow channel (2), a feeding system (3), a slag discharge port (5), a heat exchange chamber (8), a horizontal flue (9), and a cyclone separator (10), wherein the combustion chamber (1) is connected to the base, the heat exchange chamber (8) and the horizontal flue (9) are sequentially connected above the combustion chamber (1), the horizontal flue (9) is connected with the cyclone separator (10) on both sides, and the cyclone separator (10) is connected in communication with the opening at the top of the combustion chamber (1) through a pipeline to form a return feeding loop. The bottom center of the interior of the combustion chamber (1) is provided with a temperature adjusting air duct and a fuel channel (6), the temperature adjusting air duct and the fuel channel (6) are connected with a heat reflecting arch (7) above, the heat reflecting arch (7) is provided with a plurality of air supply nozzles, and the slag discharge port (5) is located at the bottom of the combustion chamber. The feeding system (3) is provided with a feeding port, the feeding system (3) is communicated with the bottom of the combustion chamber (1) through the rotating flow channel (2), the inner wall of the rotating flow channel (2) is a membrane type cooling wall (12), and the inner wall of the rotating flow channel is provided with a primary air nozzle and a secondary air nozzle (11). The outer wall of the cyclone bed combustion device is a three-dimensional conical surface structure, the three-dimensional conical surface is filled with water cooling pipes and refractory mud, the center of the top of the three-dimensional conical surface is provided with a rotating shaft, the rotating shaft is internally provided with a hollow cooling water channel, the rotating shaft is rotatably and sealingly connected with the base, the top outer wall of the combustion chamber (1) serves as the cone mouth of the three-dimensional conical surface, and the cone mouth is circumferentially and interval ly provided with a plurality of L-shaped return ports corresponding to the cyclone separators (10).

2. The cyclone combustor according to claim 1, wherein The transverse section of the rotating flow channel (2) is one of a semicircular section and a circular section, or a section with a semicircle on the left side and a semicircle on the right side and a rectangle in the middle.

3. The cyclone combustor according to claim 1, wherein The base and the rotating flow channel (2) are further provided with a fixed air chamber (4), the fixed air chamber (4) is a double-layer structure of an inner layer and an outer layer, the inner layer is a flue gas layer, the outer layer is an air layer, or the inner layer is an air layer and the outer layer is a flue gas layer, the gas in the fixed air chamber (4) enters the primary air nozzle and the secondary air nozzle (11) through the air duct at the back of the cone mouth.

4. The cyclone combustor according to claim 1, wherein The inner conical surface of the three-dimensional conical surface is a spiral channel, a plurality of nozzles are arranged in the spiral channel to ensure the oxygen or air required for particle combustion and to provide the power for particle rotation and forward movement.

5. The cyclone combustor according to claim 1, wherein The feeding port of the feeding system (3) is rotatably connected with the rotating flow channel (2).

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