Waste heat utilization system for tail flue hollow beam

Abstract

The utility model discloses a tail flue hollow beam waste heat utilization system which comprises an air inlet main pipe and an air outlet main pipe, an inlet of the air inlet main pipe is communicated with an outlet of a primary fan, and an outlet of the air inlet main pipe is communicated with one end of each hollow beam through an air inlet branch pipe. The other end of each hollow beam is communicated with an inlet of an air outlet main pipe through an air outlet branch pipe, and an outlet of the air outlet main pipe is communicated with an inlet of an air pre-heater. The air pre-heater has the advantages that a path of cold air is led out from the outlet of the primary fan and is sent to each hollow beam through the air inlet mother pipe to perform forced ventilation cooling on the hollow beams, so that overhigh temperature of the hollow beams can be avoided and deformation is reduced, and the air after heat absorption is sent to the inlet of the air pre-heater to achieve the purpose of increasing the temperature of the outlet of the air pre-heater; the purpose of utilizing heat of the hollow beam is achieved.

Description

Technical field:

[0001] The utility model relates to the technical field of circulating fluidized bed boilers, in particular to a waste heat utilization system of a hollow beam of a tail flue. Background technology:

[0002] The circulating fluidized bed boiler adopts a single drum and natural circulation mode. It is generally divided into two vertical shafts, the front and the rear. The front vertical shaft is a total suspension structure, surrounded by membrane water-cooled walls, from bottom to top, the primary air chamber, dense phase area, and dilute phase area are arranged in sequence; the tail flue is composed of high-temperature superheater, low-temperature superheater and economizer, and air preheater from top to bottom. Hollow beams for supporting superheater, economizer and air preheater are fixed between the inner walls of the tail flue. The main function of the air preheater is to preheat the cold air sent by the primary fan, and then send it to the boiler for fluidizing air. However, due to the high temperature of the tail flue, the hollow beam has the problem of high temperature and deformation, which poses a great safety hazard. Utility model content:

[0003] The utility model aims to provide a waste heat utilization system of a hollow beam of a tail flue.

[0004] The utility model is implemented by the following technical scheme: a waste heat utilization system of a tail flue hollow beam, which includes an air inlet main pipe and an air outlet main pipe, the inlet of the air inlet main pipe is connected with the outlet of a primary fan, the outlet of the air inlet main pipe is connected with one end of each hollow beam through an air inlet branch pipe, the other end of each hollow beam is connected with the inlet of the air outlet main pipe through an air outlet branch pipe, and the outlet of the air outlet main pipe is connected with the inlet of an air preheater.

[0005] Furthermore, an exhaust pipe is connected to the outlet side of the air outlet main pipe, and an exhaust control valve is installed on the exhaust pipe.

[0006] Furthermore, a temperature sensor is installed at the outlet of the tail flue, the temperature sensor is connected to the input end of the controller, and the output end of the controller is connected to the exhaust control valve.

[0007] The utility model has the advantages that cold air is drawn out from the outlet of the primary fan and sent to each hollow beam through the air inlet main pipe, so as to force ventilation and cool the hollow beam. On the one hand, it can avoid the hollow beam from being overheated and reduce deformation. On the other hand, the air after absorbing heat is sent to the inlet of the air preheater, so as to achieve the purpose of increasing the outlet temperature of the air preheater and realizing the purpose of heat utilization of the hollow beam. Description of the drawings:

[0008] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0009] Tag Name

[0010] 1-air inlet main pipe, 2-air outlet main pipe, 3-fan, 4-air inlet branch pipe, 5-hollow beam, 6-air outlet branch pipe, 7-boiler fluidizing air inlet, 8-exhaust pipe, 9-exhaust control valve, 10-temperature sensor, 11-controller, 12-air preheater, 13-tail flue. Specific implementation method:

[0011] like Figure 1 As shown, the waste heat utilization system of the hollow beam 5 in the tail flue 13 includes an air inlet main pipe 1 and an air outlet main pipe 2. The inlet of the air inlet main pipe 1 is connected to the outlet of the primary fan 3. The outlet of the air inlet main pipe 1 is connected to one end of each hollow beam 5 through the air inlet branch pipe 4. The other end of each hollow beam 5 is connected to the inlet of the air outlet main pipe 2 through the air outlet branch pipe 6. The outlet of the air outlet main pipe 2 is connected to the inlet of the air preheater 12. Part of the cold air sent by the primary fan 3 enters the air inlet main pipe 1 and then enters the hollow beam 5 through each air inlet branch pipe 4. The cold air is used to force ventilation on the hollow beam 5 to reduce the temperature of the hollow beam 5 and reduce the deformation of the hollow beam 5. The cold air that absorbs heat is discharged from the hollow beam 5 and enters the air outlet main pipe 2 through the air outlet branch pipe 6. Then, it enters the air preheater 12 together with another part of the air sent by the primary fan 3 to absorb the flue gas heat again and then be sent to the boiler as fluidizing air.

[0012] The outlet side of the air outlet main pipe 2 is connected with an exhaust pipe 8, on which an exhaust control valve 9 is installed, and a temperature sensor 10 is installed at the outlet of the tail flue 13, and the temperature sensor 10 is connected to the input end of the controller 11, and the output end of the controller is connected to the exhaust control valve 9. The temperature of the outlet of the tail flue 13 can be detected by the temperature sensor 10. When the detected temperature is higher than the set value, the opening of the exhaust control valve 9 is increased, and the inlet temperature of the air preheater 12 is reduced, so as to achieve the purpose of increasing the heat absorption of the primary air and reducing the exhaust gas temperature; when the measured temperature is lower than the set minimum value, the exhaust control valve 9 can be appropriately closed, and the inlet temperature of the air preheater 12 is increased to increase the exhaust gas temperature, so as to achieve the purpose of reducing the heat absorption of the primary air and increasing the exhaust gas temperature, thereby ensuring the normal flue gas temperature of the desulfurization tower.

[0013] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. The tail flue hollow beam waste heat utilization system is characterized by: It includes an air inlet main pipe and an air outlet main pipe. The inlet of the air inlet main pipe is connected to the outlet of the primary fan. The outlet of the air inlet main pipe is connected to one end of each hollow beam through an air inlet branch pipe. The other end of each hollow beam is connected to the inlet of the air outlet main pipe through an air outlet branch pipe. The outlet of the air outlet main pipe is connected to the inlet of the air preheater.

2. The tail flue hollow beam waste heat utilization system according to claim 1 is characterized in that: An exhaust pipe is connected to the outlet side of the air outlet main pipe, and an exhaust control valve is installed on the exhaust pipe.

3. The tail flue hollow beam waste heat utilization system according to claim 2 is characterized in that: A temperature sensor is installed at the outlet of the tail flue, the temperature sensor is connected to the input end of the controller, and the output end of the controller is connected to the exhaust control valve.

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