A fly ash fluidized bed combustion decarbonization device

Abstract

The invention relates to the technical field of fly ash decarbonization, and discloses a fly ash fluidized bed combustion decarbonization device, comprising a fly ash silo, a blower, an electric heater, an air powder classifier, a spiral feeder, a furnace, an ash cooler, a cyclone separator, a return valve, an air heat exchanger, a dust collector, an induced draft fan and a chimney. According to the difference in specific gravity and particle size between unburned ember carbon and burned ember carbon in the fly ash, the fly ash can be carried by hot air into the air powder classifier for screening, and fly ash with larger particles and higher carbon content falls to the bottom of the air powder classifier and enters the next step, so that only a part of the fly ash needs to be reburned, thereby improving the work efficiency of reducing the carbon content of the fly ash, and at the same time increasing the proportion of the carbon content in the fly ash burned in the furnace, so that the fly ash in the furnace can be stably burned and release a large amount of heat, thereby improving the utilization rate of the fly ash.

Description

Technical Field

[0001] The invention relates to the technical field of fly ash decarbonization, in particular to a fly ash fluidized bed combustion decarbonization device. Background Art

[0002] Fly ash is the fine ash collected from the flue gas after coal combustion. Fly ash is the main solid waste discharged from coal-fired power plants. With the development of the electric power industry, the fly ash emissions from coal-fired power plants have increased year by year. It is urgent to increase the resource utilization of fly ash, but the carbon content in fly ash seriously affects its comprehensive utilization. Therefore, it is necessary to further decarbonize the fly ash and reduce the proportion of carbon in the fly ash.

[0003] According to the fly ash fluidized bed combustion decarbonization device proposed in Patent No. 2011103276556, the fly ash with a carbon content greater than 12% is re-combusted and cooled to reduce the carbon content of the fly ash. However, this technology has the following shortcomings:

[0004] Firstly, this device can only reburn fly ash with a carbon content higher than 12%, and its scope of action is limited. At the same time, all fly ash is reheated again, which consumes a lot of resources. Secondly, the furnace and ash cooler in this device have complex structures, and the fly ash is in powder form and will accumulate, which cannot be removed by overflow. Summary of the invention

[0005] The present invention provides a fly ash fluidized bed combustion decarbonization device, which has the advantages of simple structure, wide action range, and can further decarbonize fly ash of various carbon contents, thus solving the above problems of insufficient action range and unreasonable structure.

[0006] The present invention provides the following technical solutions: a fly ash fluidized bed combustion decarbonization device, comprising a fly ash silo, a blower, an electric heater, an air classifier, a screw feeder, a furnace, an ash cooler, a cyclone separator, a return valve, an oxygen-enriched ignition and combustion stabilization device, an air heat exchanger, a dust collector, an induced draft fan and a chimney, a high-temperature resistant ash inlet valve is fixedly installed in the middle part of the furnace connected to the ash cooler, a metering valve is fixedly installed at the lower port of the fly ash silo, the fly ash silo, the blower and the air classifier are connected by an L-shaped pipeline transmission, a pipeline is opened on the right side of the upper surface of the air classifier and is connected to the air heat exchanger for transmission, the bottom of the air classifier is connected to the furnace through a pipeline installed with a screw feeder, and an oxygen-enriched ignition and combustion stabilization device is fixedly installed on the right side of the furnace and below the return valve.

[0007] Preferably, the air powder classifier includes a fixed frame, a powder inlet, an air guide plate, a rotating body, a fixed shaft and a powder outlet, the air guide plate is fixedly installed in the inner cavity of the fixed frame and close to the powder inlet, the fixed shaft is movably installed on the upper surface of the fixed frame and passes through the fixed frame, the rotating body is fixedly sleeved on the middle and upper part of the fixed shaft, and the crushing blades are fixedly installed on the bottom of the fixed shaft.

[0008] Preferably, the furnace includes a refractory insulation layer, a refractory heat transfer layer, a hollow layer one, a rotating air outlet, a spiral heater, a furnace ash discharge pipe, an accident ash discharge pipe, a furnace outlet flue, a return material port and an oxygen-enriched ignition warm combustion channel, a hollow layer one is provided between the refractory insulation layer and the refractory heat transfer layer, a rotating air outlet is provided at the bottom of the refractory heat transfer layer, and the hollow layer one is connected to the air heat exchanger through a pipe.

[0009] Preferably, the ash cooler includes a thermal insulation layer, a heat dissipation layer, a second hollow layer, transverse air outlets, lateral air outlets, an air-cooled serpentine tube bundle and an ash cooler ash discharge pipe. A second hollow layer is provided between the thermal insulation layer and the heat dissipation layer. A uniform array of transverse air outlets is provided on the left wall of the heat dissipation layer. Lateral air outlets are provided on the front and back of the heat dissipation layer. The transverse air outlets and the lateral air outlets connect the second hollow layer with the inner cavity of the heat dissipation layer. The bottom of the inner cavity of the ash cooler is two conical inclined grooves.

[0010] Preferably, the blower is connected to the air-cooled serpentine tube bundle and the second hollow layer, and the first hollow layer is connected to the air heat exchanger.

[0011] Preferably, the cyclone separator is connected to the furnace through a return valve.

[0012] The present invention has the following beneficial effects:

[0013] 1. Through the setting of the air classifier, the fly ash can be carried into the air classifier by hot air for screening according to the difference in specific gravity and particle size between the unburned carbon and the burned carbon in the fly ash. The fly ash with larger particles and higher carbon content falls to the bottom of the air classifier and enters the next process, so that only a part of the fly ash needs to be reburned, which improves the work efficiency of reducing the carbon content of the fly ash. At the same time, the proportion of carbon content in the fly ash burned in the furnace is increased, so that the fly ash in the furnace can burn stably and release a large amount of heat, which improves the utilization rate of the fly ash. The fine fly ash contains less carbon and is burned by hot air, which further reduces the carbon content in the fly ash.

[0014] 2. Through the arrangement of the hollow layer 1 and the rotating air outlet, the air in the hollow layer 1 is heated again and then enters the inner cavity of the refractory heat transfer layer to heat the fly ash, thereby increasing the temperature of the fly ash and ensuring the combustion of the fly ash. At the same time, the rotating air outlet can blow away the fly coal close to the inner wall of the refractory heat transfer layer and gather it to the middle of the refractory heat transfer layer, thereby increasing the aggregation of the fly ash and making it burn more effectively. At the same time, the fly ash that has been burned is made to approach the ash discharge pipe of the furnace in the middle, thereby reducing the accumulation of fly ash and improving the cleaning efficiency of fly ash. Through the arrangement of the cyclone separator and the furnace, the ash discharged from the flue at the furnace outlet contains unburned ash, which is sent back into the furnace under the action of the cyclone separator and the return valve, and the re-entering fly ash is ignited by oxygen-enriched ignition and stabilization combustion device, thereby effectively forming a high-temperature flame, increasing the burnout rate of the fly ash and ensuring the burnout of the fly ash. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a front view schematic diagram of the structure of the present invention;

[0016] Figure 2 This is a schematic diagram of the air powder classifier 4 of the present invention;

[0017] Figure 3 This is a schematic diagram of the furnace 6 of the structure of the present invention;

[0018] Figure 4 This is a schematic diagram of the ash cooler structure of the present invention;

[0019] Figure 5 For the present invention Figure 3 AA schematic diagram;

[0020] Figure 6 For the present invention Figure 4 BB schematic diagram.

[0021] In the figure: 1. fly ash silo; 2. blower; 3. electric heater; 4. air powder separator; 41. fixed frame; 42. powder inlet; 43. air guide vane; 44. rotating body; 45. fixed shaft; 46. powder outlet; 5. screw feeder; 6. furnace; 61. refractory insulation layer; 62. refractory heat transfer layer; 63. hollow layer 1; 64. rotating air outlet; 65. screw heater; 66. furnace ash discharge pipe; 67. accident ash discharge pipe; 68. 8. Furnace outlet flue; 69. Return material port; 610. Oxygen-enriched ignition and warm combustion channel; 7. Ash cooler; 71. Insulation layer; 72. Heat dissipation layer; 73. Hollow layer 2; 74. Horizontal air outlet; 75. Lateral air outlet; 76. Air-cooled serpentine tube bundle; 77. Ash cooler ash discharge pipe; 8. Cyclone separator; 9. Return material valve; 10. Oxygen-enriched ignition and stable combustion device; 11. Air heat exchanger; 12. Dust collector; 13. Draft fan; 14. Chimney. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings 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 part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] See also Figure 1-6 A fly ash fluidized bed combustion decarbonization device comprises a fly ash silo 1, a blower 2, an electric heater 3, an air classifier 4, a spiral feeder 5, a furnace 6, an ash cooler 7, a cyclone separator 8, a return valve 9, an oxygen-enriched ignition and combustion stabilizing device 10, an air heat exchanger 11, a dust collector 12, an induced draft fan 13 and a chimney 14. A high-temperature resistant ash inlet valve is fixedly installed in the middle part where the furnace 6 is connected to the ash cooler 7, a metering valve is fixedly installed at the lower port of the fly ash silo 1, the fly ash silo 1, the blower 2 and the air classifier 4 are connected by an L-shaped pipeline, a pipeline is opened on the right side of the upper surface of the air classifier 4 and is connected to the air heat exchanger 11, the bottom of the air classifier 4 is connected to the furnace 6 by a pipeline installed with a spiral feeder 5, and an oxygen-enriched ignition and combustion stabilizing device 10 is fixedly installed on the right side of the furnace 6 and below the return valve 9.

[0024] Among them, the air powder classifier 4 includes a fixed frame 41, a powder inlet 42, an air guide plate 43, a rotating body 44, a fixed shaft 45 and a powder outlet 46. The air guide plate 43 is fixedly installed in the inner cavity of the fixed frame 41 and is close to the powder inlet 42. The fixed shaft 45 is movably installed on the upper surface of the fixed frame 41 and penetrates the fixed frame 41. The rotating body 44 is fixedly sleeved on the fixed shaft 45. The hot air generated by the blower 2 and the electric heater 3 carries the fly ash into the powder inlet 42. Through the guidance of the air guide plate 43 and under the action of the rotating body 44, the fly ash with a higher carbon content and coarse particles falls to the bottom of the fixed frame 41, and the finer fly ash is discharged from the powder outlet 46. The fly ash is further screened to prepare for the next step and improve the carbon removal efficiency.

[0025] The furnace 6 includes a refractory insulation layer 61, a refractory heat transfer layer 62, a hollow layer 63, a rotating air outlet 64, a spiral heater 65, a furnace ash discharge pipe 66, an accident ash discharge pipe 67, a furnace outlet flue 68, a return port 69 and an oxygen-enriched ignition temperature combustion channel 610. A hollow layer 63 is provided between the refractory insulation layer 61 and the refractory heat transfer layer 62. A rotating air outlet 64 is provided at the bottom of the refractory heat transfer layer 62. The hollow layer 63 is connected to the air heat exchanger 11 through a pipeline. The air entering the hollow layer 63 is The air is heated again and introduced into the inner cavity of the refractory heat transfer layer 62 through the rotating air outlet 64 to heat the fly ash, thereby increasing the temperature of the fly ash and ensuring the combustion of the fly ash. At the same time, the rotating air outlet 64 can blow away the fly coal close to the inner wall of the refractory heat transfer layer 62 and gather it to the middle of the refractory heat transfer layer 62, thereby increasing the aggregation of the fly ash and making it burn more efficiently. At the same time, the fly ash that has finished burning is made to approach the ash discharge pipe 66 in the middle of the furnace, thereby reducing the accumulation of fly ash and improving the efficiency of fly ash cleaning.

[0026] The ash cooler includes an insulation layer 71, a heat dissipation layer 72, a hollow layer 2 73, a transverse air outlet 74, a lateral air outlet 75, an air-cooling serpentine tube bundle 76, and an ash cooler ash discharge pipe 77. A hollow layer 2 73 is provided between the insulation layer 71 and the heat dissipation layer 72. A uniform array of transverse air outlets 74 are provided on the left wall of the heat dissipation layer 72. Side air outlets 75 are provided on the front and back of the heat dissipation layer 72. The transverse air outlets 74 and the lateral air outlets 75 connect the hollow layer 2 73 with the inner cavity of the heat dissipation layer 72. The bottom of the inner cavity of the ash cooler 7 is two circular Conical inclined chute, after the fly ash enters the ash cooler 7 from the furnace 6, part of the cold air is conducted from the hollow layer 2 73 through the lateral air outlet 74 and the lateral air outlet 75 into the heat dissipation layer 72 to cool the fly ash, and the other part is conducted from the air-cooled serpentine tube bundle 76 to cool the fly ash. The wind conducted by the lateral air outlet 74 and the lateral air outlet 75 can cool the fly ash on the one hand, and on the other hand, it can push the fly ash entering from the left side to the right side, thereby increasing the heat dissipation area and heat dissipation effect of the fly ash and preventing the fly ash from accumulating on the left side.

[0027] Among them, the air supply fan 2 is connected with the air-cooled serpentine tube bundle 76 and the hollow layer 2 73, the hollow layer 1 63 is connected with the air heat exchanger 11, and the hot air channel in the air classifier 4 performs heat exchange in the air heat exchanger 11 and then conducts into the hollow layer 1 63, which improves the utilization of heat and reduces the consumption of resources.

[0028] Among them, the cyclone separator 8 is connected to the furnace 6 through the return valve 9. The fly ash discharged from the furnace outlet flue 68 contains unburned coal ash, which is separated in the cyclone separator 8 and falls into the return valve 9, and is sent into the furnace 6 again by the return valve 9. At the same time, the oxygen-enriched ignition and combustion stabilization device 10 performs oxygen-enriched ignition on the re-entering fly ash, which can effectively form a high-temperature flame, improve the burnout rate of the fly ash, and ensure the burnout of the fly ash.

[0029] Working principle: pour fly ash into fly ash silo 1, turn on air blower 2 and electric heater 3 to obtain hot air of a certain temperature, and release fly ash under the control of metering pump, and the hot air carries fly ash into air classifier 4 for screening, and fly ash with high carbon content is conducted into furnace 6 by screw feeder 5 for combustion, and falls into ash cooler 7 for cooling after combustion to obtain fly ash with low carbon content, and fine fly ash with low carbon content in air classifier 4 is carried and heated by hot air to burn, and hot air enters air heat exchanger 11 for heat exchange, and fine fly ash enters dust collector 12 for cooling, and the hot air after exchange enters hollow layer 1 63, and cold air in hollow layer 2 73 and air-cooled serpentine tube bundle 76 is provided by air blower 2.

[0030] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A fly ash fluidized bed combustion decarbonization device, comprising a fly ash silo (1), a blower (2), an electric heater (3), an air powder classifier (4), a screw feeder (5), a furnace (6), an ash cooler (7), a cyclone separator (8), a return valve (9), an oxygen-enriched ignition and stabilizing combustion device (10), an air heat exchanger (11), a dust collector (12), an induced draft fan (13) and a chimney (14), wherein a high temperature resistant ash inlet valve is fixedly installed in the middle of the furnace (6) where it is connected to the ash cooler (7), and characterized in that: A metering valve is fixedly installed at the lower port of the fly ash silo (1); the fly ash silo (1), the blower (2) and the air classifier (4) are connected by an L-shaped pipeline; a pipeline is provided on the right side of the upper surface of the air classifier (4) and is connected by an air heat exchanger (11); the bottom of the air classifier (4) is connected by a pipeline with a screw feeder (5) installed and is connected by a furnace (6); an oxygen-enriched ignition and stabilizing combustion device (10) is fixedly installed on the right side of the furnace (6) and below the return valve (9); The furnace (6) comprises a refractory insulation layer (61), a refractory heat transfer layer (62), a hollow layer one (63), a rotating air outlet (64), a spiral heater (65), a furnace ash discharge pipe (66), an accident ash discharge pipe (67), a furnace outlet flue (68), a return material port (69) and an oxygen-enriched ignition warm combustion channel (610); a hollow layer one (63) is provided between the refractory insulation layer (61) and the refractory heat transfer layer (62); a rotating air outlet (64) is provided at the bottom of the refractory heat transfer layer (62); and the hollow layer one (63) is connected to the air heat exchanger (11) through a pipeline.

2. The fly ash fluidized bed combustion decarbonization device according to claim 1, characterized in that: The air powder classifier (4) comprises a fixed frame (41), a powder inlet (42), an air guide plate (43), a rotating body (44), a fixed shaft (45) and a powder outlet (46); the air guide plate (43) is fixedly mounted in the inner cavity of the fixed frame (41) and close to the powder inlet (42); the fixed shaft (45) is movably mounted on the upper surface of the fixed frame (41) and penetrates the fixed frame (41); and the rotating body (44) is fixedly sleeved on the fixed shaft (45).

3. The fly ash fluidized bed combustion decarbonization device according to claim 1, characterized in that: The ash cooler (7) comprises a heat insulation layer (71), a heat dissipation layer (72), a second hollow layer (73), a transverse air outlet (74), a lateral air outlet (75), an air-cooling serpentine tube bundle (76) and an ash cooler ash discharge pipe (77); a second hollow layer (73) is provided between the heat insulation layer (71) and the heat dissipation layer (72); a left wall of the heat dissipation layer (72) is provided with transverse air outlets (74) arranged uniformly in an array; a front side and a back side of the heat dissipation layer (72) are provided with lateral air outlets (75); the transverse air outlets (74) and the lateral air outlets (75) connect the second hollow layer (73) with the inner cavity of the heat dissipation layer (72); and the bottom of the inner cavity of the ash cooler (7) is two conical inclined grooves.

4. The fly ash fluidized bed combustion decarbonization device according to claim 3, characterized in that: The air blower (2) is in communication with the air-cooling serpentine tube bundle (76) and the second hollow layer (73).

5. The fly ash fluidized bed combustion decarbonization device according to claim 1, characterized in that: The cyclone separator (8) is connected to the furnace (6) via a return valve (9).

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