Boiler flue gas waste heat utilization system

Abstract

The utility model relates to the technical field of thermal power plant flue gas waste heat utilization, and discloses a boiler flue gas waste heat utilization system which comprises a boiler body, a drying device and a feeding device, the drying device comprises a box body, two draught fans distributed in a mirror image mode are fixedly connected to one side of the interior of the box body, a heat exchanger is fixedly connected to the interior of the box body, and the feeding device is fixedly connected to the other side of the box body. The two sides of the interior of the box body are fixedly connected with material guiding plates correspondingly, and one side of the drying device is fixedly connected with a feeding device. According to the boiler flue gas waste heat utilization system, through the arrangement of the boiler body, the drying device and the feeding device, coal entering the boiler body is pre-dried, due to the fact that water is usually sprayed to prevent dust in the transportation process of the coal, the water content is high, and the coal is heated and dried in the drying device through high-temperature flue gas generated through combustion in the boiler body; the water content of the coal is reduced, the dried coal is easier to fully burn, the combustion efficiency is improved, and smoke and pollutants generated by incomplete combustion are reduced.

Description

Technical Field

[0001] This application relates to the field of waste heat utilization technology for flue gas in thermal power plants, specifically a waste heat utilization system for boiler flue gas. Background Technology

[0002] A thermal power plant boiler uses combustibles to heat water and generate steam, converting the chemical energy of the combustibles into thermal energy. The steam pressure drives the turbine to rotate, converting the thermal energy into mechanical energy. Then, the turbine drives the generator to rotate, converting the mechanical energy into electrical energy. However, thermal power plant boilers need to emit flue gas when burning combustibles.

[0003] However, the flue gas from existing thermal power plant boilers is only used to preheat boiler feedwater in economizers, resulting in a still relatively high flue gas temperature after passing through the economizer. This fails to fully utilize the waste heat in the flue gas, leading to waste of waste heat and low energy utilization, thus preventing the effective use of flue gas. Utility Model Content

[0004] To address the shortcomings of existing technologies, this application provides a boiler flue gas waste heat utilization system, which has the advantages of fully utilizing flue gas waste heat. It solves the problem that in existing thermal power plant boilers, flue gas is only used for preheating boiler feedwater in the economizer, resulting in a still high flue gas temperature after passing through the economizer. This fails to fully utilize the waste heat in the flue gas, leading to waste of waste heat, low energy utilization, and ineffective utilization of flue gas.

[0005] To achieve the above objectives, this application provides the following technical solution: a boiler flue gas waste heat utilization system, comprising a furnace body, a drying device, and a feeding device. The drying device includes a box body, with two fans arranged in a mirror image fixedly connected to one side of the box body. A heat exchanger is fixedly connected inside the box body, and guide plates are fixedly connected to both sides of the box body. A first conveyor belt is fixedly installed on one side of the bottom of the box body, and a discharge port is opened on one side of the bottom of the box body. A feeding device is fixedly connected to one side of the drying device, and an exhaust pipe is fixedly connected to one side of the bottom of the drying device. A feeding device is fixedly connected to the end of the bottom of the drying device away from the exhaust pipe, and the output end of the feeding device is fixedly connected to the furnace body.

[0006] The above scheme, through the setup of the furnace body, drying device, and feeding device, pre-dries the coal entering the furnace body. Since coal is usually sprayed with water for dust prevention during transportation, its moisture content is high. By utilizing the high-temperature flue gas generated during combustion in the furnace body, the coal is heated and dried in the drying device, reducing its moisture content. Two mirror-distributed fans are installed inside the drying device, which helps to create a uniform airflow within the device. A heat exchanger allows the waste heat from the boiler flue gas to heat the air entering the device, thus providing a heat source for coal drying. The guide plate is designed to extend the residence time of the coal inside the drying device, ensuring thorough drying. The first conveyor belt is used for automatic transport of the dried coal, and the feeding device delivers the dried coal into the furnace body for combustion. The dried coal is easier to burn completely, improving combustion efficiency and reducing flue gas and pollutants generated from incomplete combustion. This device utilizes the thermal energy of high-temperature flue gas to dry coal, improving combustion efficiency and reducing energy waste and environmental pollution.

[0007] Furthermore, each of the two guide plates has two support plates fixedly connected to its bottom end in a mirror-shaped arrangement, and each of the two guide plates has a vibration motor fixedly connected to its bottom end.

[0008] With the above scheme, the guide plate is fixed on both sides inside the box. Its main function is to guide the flow direction of coal inside the box, prolong the residence time of coal in the drying device, and make full contact with the hot air inside the box, thereby improving the drying efficiency. The main function of the support plate is to provide stable support. The support plate can distribute the weight borne by the guide plate and improve the firmness of the guide plate. The main function of the vibration motor is to generate vibration, so that the guide plate and the coal on it will vibrate slightly, allowing the coal to pass through the guide plate smoothly.

[0009] Furthermore, a dustproof net is fixedly connected to one side of the box.

[0010] The above method is used to prevent dust and impurities from entering the interior of the enclosure.

[0011] Furthermore, the feeding device includes a feeding pipe, and a second conveyor belt is fixedly installed at the bottom of the feeding pipe.

[0012] The above scheme allows the feeding device to continuously and stably feed coal from the storage area into the drying device for drying, and the coal is then conveyed to the drying area via a second conveyor belt.

[0013] Furthermore, the feeding device includes a feeding pipe, a threaded rod is rotatably arranged inside the feeding pipe, a drive motor is fixedly connected to the end of the feeding pipe away from the furnace body, the output end of the drive motor passes through one end of the feeding pipe and is fixedly connected to the threaded rod, and a feed hopper is fixedly connected to one side of the outer wall of the feeding pipe.

[0014] According to the above scheme, the feeding device is used to transport the coal dried by the drying device into the furnace body for combustion. The drive motor provides rotational power to the threaded rod, which is rotatably installed inside the feeding pipe. The rotational motion pushes the coal forward in the feeding pipe. The feed hopper is fixed on one side of the outer wall of the feeding pipe to guide the coal into the feeding pipe.

[0015] Furthermore, an air collecting hood is fixedly connected to the side of the housing away from the dustproof net, an air inlet pipe is fixedly connected to the upper end of the exhaust pipe, a connecting pipe is fixedly connected to the end of the air collecting hood away from the housing, and the end of the connecting pipe away from the air collecting hood is fixedly connected to the air inlet pipe.

[0016] With the above solution, the air collection hood is fixed on the side of the box away from the dust screen, and is used to collect hot air with high moisture content inside the box. The design of the air collection hood can ensure that the hot air with high moisture content can be smoothly guided out of the box and discharged into the exhaust pipe, avoiding accumulation inside the box and affecting the normal operation of the system. The exhaust pipe serves as the channel for subsequent processing.

[0017] Furthermore, the input end of the heat exchanger is installed through the upper end of the casing, and the input end of the heat exchanger is fixedly connected to the furnace body.

[0018] With the above solution, the input end of the heat exchanger is fixedly connected to the furnace body, ensuring that the flue gas can be directly discharged from the furnace body and enter the heat exchanger for waste heat utilization.

[0019] Furthermore, the output end of the heat exchanger is disposed through the bottom end of the housing, and the output end of the heat exchanger extends into the interior of the exhaust pipe.

[0020] With the above solution, the output end of the heat exchanger extends through the bottom of the housing, allowing the flue gas after heat exchange to be discharged directly from the bottom of the heat exchanger. The output end extends into the exhaust pipe, ensuring that the flue gas can smoothly enter the exhaust pipe and then be discharged from the system for further treatment.

[0021] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0022] This boiler flue gas waste heat utilization system, through the arrangement of a furnace body, a drying device, and a feeding device, pre-dries the coal entering the furnace body. Since coal is usually sprayed with water for dust prevention during transportation, its moisture content is relatively high. By utilizing the high-temperature flue gas generated during combustion in the furnace body, the coal is heated and dried in the drying device, reducing its moisture content. Two mirror-distributed fans are installed inside the drying device, which helps to form a uniform airflow within the device. A heat exchanger allows the waste heat from the boiler flue gas to heat the air entering the device, thus providing a heat source for coal drying. The guide plate is designed to extend the residence time of the coal inside the drying device, ensuring thorough drying. A first conveyor belt is used for automatic transport of the dried coal, and the feeding device delivers the dried coal into the furnace body for combustion. The dried coal is easier to burn completely, improving combustion efficiency and reducing flue gas and pollutants generated from incomplete combustion. This device utilizes the thermal energy of high-temperature flue gas to dry coal, improving coal combustion efficiency and reducing energy waste and environmental pollution. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of this application;

[0024] Figure 2 This is a schematic diagram of the internal structure of the drying device according to this application.

[0025] Figure 3 This is a schematic diagram of the transmission device structure of this application;

[0026] Figure 4 This is a schematic diagram of the guide plate structure of this application;

[0027] Figure 5 This is a schematic diagram of the exhaust structure of the present application.

[0028] In the picture:

[0029] 1. Furnace body; 2. Drying device; 201. Box body; 202. Fan; 203. Heat exchanger; 204. Guide plate; 205. Support plate; 206. Vibrating motor; 207. First conveyor belt; 208. Discharge port; 209. Dustproof net; 3. Feeding device; 301. Feeding pipe; 302. Second conveyor belt; 4. Exhaust pipe; 5. Feeding device; 501. Feeding pipe; 502. Threaded rod; 503. Drive motor; 504. Feeding hopper; 6. Air collection hood; 7. Air inlet pipe; 8. Connecting pipe. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0031] Please see Figure 1 , Figure 2 and Figure 3 This embodiment of a boiler flue gas waste heat utilization system includes a furnace body 1, a drying device 2, and a feeding device 5. The furnace body 1, drying device 2, and feeding device 5 are used to pre-dry the coal entering the furnace body 1. Since coal is usually sprayed with water for dust prevention during transportation, its moisture content is high. By utilizing the high-temperature flue gas generated during combustion within the furnace body 1, the coal is heated and dried within the drying device 2, reducing its moisture content. The drying device 2 includes a housing 201. Two fans 202, arranged in a mirror image, are fixedly connected to one side of the housing 201. A heat exchanger 203 is fixedly connected inside the housing 201. The two mirror-image fans 202 help to form a uniform airflow inside the housing 201. The heat exchanger 203 allows the waste heat in the boiler flue gas to be used for... The air entering the chamber 201 is heated to provide a heat source for drying the coal. Guide plates 204 are fixedly connected to both sides of the inside of the chamber 201. The guide plates 204 are designed to extend the residence time of the coal inside the drying device 2, so that the coal can be fully dried. A first conveyor belt 207 is fixedly installed on one side of the bottom of the chamber 201. A discharge port 208 is opened on one side of the bottom of the chamber 201. A feeding device 3 is fixedly connected to one side of the drying device 2. An exhaust pipe 4 is fixedly connected to one side of the bottom of the drying device 2. A feeding device 5 is fixedly connected to the end of the bottom of the drying device 2 away from the exhaust pipe 4. The output end of the feeding device 5 is fixedly connected to the furnace body 1. The first conveyor belt 207 is used for automatic conveying of the dried coal and feeding the dried coal into the furnace body 1 for combustion through the feeding device 5.

[0032] Please see Figure 2 , Figure 3 and Figure 4Two guide plates 204 are fixedly connected to their bottom ends by two mirror-distributed support plates 205. Vibration motors 206 are also fixedly connected to the bottom ends of both guide plates 204. The guide plates 204 are fixed to both sides inside the housing 201. Their main function is to guide the flow of coal inside the housing 201, prolong the residence time of coal in the drying device 2, and ensure sufficient contact with the hot air inside the housing 201, thereby improving drying efficiency. The support plates 205 provide stable support and can distribute the weight borne by the guide plates 204, improving the stability of the guide plates 204. The vibration motors 206 generate vibration, causing slight vibration of the guide plates 204 and the coal on them, allowing the coal to pass smoothly through the guide plates 204. A dustproof net 209 is fixedly connected to one side of the housing 201 to prevent dust and impurities from entering the housing 201. The feeding device 3 includes a feeding pipe 301. A second conveyor belt 302 is fixedly installed at the bottom. The feeding device 3 is used to continuously and stably feed coal from the storage area into the drying device 2 for drying. The second conveyor belt 302 transports the coal to the drying area. The feeding device 5 includes a feeding pipe 501. A threaded rod 502 is rotatably installed inside the feeding pipe 501. A drive motor 503 is fixedly connected to the end of the feeding pipe 501 away from the furnace body 1. The output end of the drive motor 503 passes through one end of the feeding pipe 501 and is fixedly connected to the threaded rod 502. A feed hopper 504 is fixedly connected to one side of the outer wall of the feeding pipe 501. The feeding device 5 is used to transport the coal dried by the drying device 2 into the furnace body 1 for combustion. The drive motor 503 provides rotational power to the threaded rod 502. The threaded rod 502 is rotatably installed inside the feeding pipe 501. The rotational motion pushes the coal forward in the feeding pipe 501. The feed hopper 504 is fixed to one side of the outer wall of the feeding pipe 501 to guide the coal into the feeding pipe 501.

[0033] Please see Figure 1 , Figure 2 and Figure 5A dust collector hood 6 is fixedly connected to the side of the housing 201 away from the dust filter 209. An air inlet pipe 7 is fixedly connected to the upper end of one side of the exhaust pipe 4. A connecting pipe 8 is fixedly connected to the end of the dust collector hood 6 away from the housing 201. The end of the connecting pipe 8 away from the dust collector hood 6 is fixedly connected to the air inlet pipe 7. The dust collector hood 6 is fixed to the side of the housing 201 away from the dust filter 209 and is used to collect hot air with high moisture content inside the housing 201. The design of the dust collector hood 6 ensures that hot air with high moisture content can be smoothly guided out of the housing 201 and discharged into the exhaust pipe 4, avoiding accumulation inside the housing 201 and affecting the normal operation of the system. The exhaust pipe 4 serves as a channel for subsequent processing and heat exchange. The input end of heat exchanger 203 is set through the upper end of the housing 201. The input end of heat exchanger 203 is fixedly connected to the furnace body 1, ensuring that the flue gas can be directly discharged from the furnace body 1 and enter the heat exchanger 203 for waste heat utilization. The output end of heat exchanger 203 is set through the bottom end of housing 201 and extends into the exhaust pipe 4. The output end of heat exchanger 203 extends through the bottom end of housing 201, so that the flue gas after heat exchange can be directly discharged from the bottom of heat exchanger 203. The output end extends into the exhaust pipe 4, ensuring that the flue gas can smoothly enter the exhaust pipe 4 and then be discharged from the system for subsequent treatment.

[0034] In this embodiment, the boiler flue gas waste heat utilization system, through the arrangement of the furnace body 1, drying device 2, and feeding device 5, pre-dries the coal entering the furnace body 1. Since coal is usually sprayed with water for dust prevention during transportation, its moisture content is relatively high. By utilizing the high-temperature flue gas generated during combustion within the furnace body 1 to heat and dry the coal in the drying device 2, the moisture content of the coal is reduced. Two mirror-distributed fans 202 are installed inside the housing 201 of the drying device 2, which helps to form a uniform airflow inside the housing 201. The heat exchanger 203 allows the waste heat in the boiler flue gas to be used for... The air entering the chamber 201 is heated to provide a heat source for coal drying. The guide plate 204 is designed to extend the residence time of the coal inside the drying device 2, so that the coal can be fully dried. The first conveyor belt 207 is used for automatic conveying of the dried coal and feeds the dried coal into the furnace 1 for combustion through the feeding device 5. The dried coal is easier to burn completely, which improves the combustion efficiency and reduces the flue gas and pollutants generated by incomplete combustion. This device uses the heat energy of high-temperature flue gas to dry coal, which improves the combustion efficiency of coal and reduces energy waste and environmental pollution.

[0035] It should be noted that the two guide plates 204 are staggered, forming an inclined channel, which increases the residence time of the material on the guide plates 204 and helps the coal to dry fully.

[0036] The working principle of the above embodiments is as follows:

[0037] Coal is continuously and stably fed into the housing 201 of the drying device 2 through the feed pipe 301 of the feeding device 3 and the second conveyor belt 302. Two mirror-distributed fans 202 are installed inside the housing 201 to help create a uniform airflow. The input end of the heat exchanger 203 is fixedly connected to the furnace body 1, receiving the high-temperature flue gas generated by combustion in the furnace body 1 and using the waste heat in the flue gas to heat the air entering the housing 201, providing a heat source for coal drying. Coal flows on the guide plate 204 inside the housing 201. The design of the guide plate 204 extends the residence time of the coal in the drying device 2, allowing the coal to fully contact the hot air, thereby improving drying efficiency. The support plate 205 provides stable support for the guide plate 204. The vibration motor 206 causes slight vibration of the guide plate 204 and the coal on it, ensuring smooth passage of the coal through the guide plate 204. The dried coal is then conveyed by the first conveyor belt 207 at the bottom of the housing 201. The dried coal is discharged from the discharge port 208 on one side of the bottom and enters the feeding device 5. The feeding device 5 includes a feeding pipe 501, with a threaded rod 502 rotatably installed inside. The drive motor 503 provides rotational power to the threaded rod 502, pushing the coal forward in the feeding pipe 501. The feed hopper 504 is fixed to one side of the outer wall of the feeding pipe 501 to guide the coal into the feeding pipe 501. The dried coal is fed into the furnace body 1 for combustion through the feeding device 5. The box body 201 is located away from the dust screen 209. A side-fixed air collecting hood 6 is used to collect hot air with high moisture content inside the box 201. The air collecting hood 6 is fixedly connected to the air inlet pipe 7 of the exhaust pipe 4 through the connecting pipe 8, ensuring that the hot air with high moisture content can be smoothly guided out of the box 201 and discharged into the exhaust pipe 4. The output end of the heat exchanger 203 passes through the bottom of the box 201 and extends into the exhaust pipe 4, so that the flue gas after heat exchange can be directly discharged from the bottom of the heat exchanger 203 and enter the exhaust pipe 4 for further treatment.

[0038] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0039] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A boiler flue gas waste heat utilization system, comprising a furnace body (1), a drying device (2), and a feeding device (5), characterized in that: The drying device (2) includes a box (201), two fans (202) arranged in a mirror image are fixedly connected to one side inside the box (201), a heat exchanger (203) is fixedly connected inside the box (201), a guide plate (204) is fixedly connected to both sides inside the box (201), a first conveyor belt (207) is fixedly installed on one side of the bottom inside the box (201), a discharge port (208) is opened on one side of the bottom of the box (201), a feeding device (3) is fixedly connected to one side of the drying device (2), an exhaust pipe (4) is fixedly connected to one side of the bottom of the drying device (2), a feeding device (5) is fixedly connected to the end of the bottom of the drying device (2) away from the exhaust pipe (4), and the output end of the feeding device (5) is fixedly connected to the furnace body (1).

2. The boiler flue gas waste heat utilization system according to claim 1, characterized in that: Two support plates (205) are fixedly connected to the bottom of each of the two guide plates (204) in a mirror-shaped arrangement, and a vibration motor (206) is fixedly connected to the bottom of each of the two guide plates (204).

3. The boiler flue gas waste heat utilization system according to claim 1, characterized in that: A dustproof net (209) is fixedly connected to one side of the box (201).

4. A boiler flue gas waste heat utilization system according to claim 1, characterized in that: The feeding device (3) includes a feeding pipe (301), and a second conveyor belt (302) is fixedly installed at the bottom of the inside of the feeding pipe (301).

5. A boiler flue gas waste heat utilization system according to claim 1, characterized in that: The feeding device (5) includes a feeding pipe (501), a threaded rod (502) is rotatably provided inside the feeding pipe (501), a drive motor (503) is fixedly connected to one end of the feeding pipe (501) away from the furnace body (1), the output end of the drive motor (503) passes through one end of the feeding pipe (501) and is fixedly connected to the threaded rod (502), and a feed hopper (504) is fixedly connected to one side of the outer wall of the feeding pipe (501).

6. A boiler flue gas waste heat utilization system according to claim 1, characterized in that: A dust collector hood (6) is fixedly connected to the side of the housing (201) away from the dustproof net (209). An air inlet pipe (7) is fixedly connected to the upper end of the side of the exhaust pipe (4). A connecting pipe (8) is fixedly connected to the end of the dust collector hood (6) away from the housing (201). The end of the connecting pipe (8) away from the dust collector hood (6) is fixedly connected to the air inlet pipe (7).

7. A boiler flue gas waste heat utilization system according to claim 1, characterized in that: The input end of the heat exchanger (203) is installed through the upper end of the box body (201), and the input end of the heat exchanger (203) is fixedly connected to the furnace body (1).

8. A boiler flue gas waste heat utilization system according to claim 1, characterized in that: The output end of the heat exchanger (203) is installed through the bottom of the housing (201), and the output end of the heat exchanger (203) extends into the exhaust pipe (4).

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