Boiler waste heat recovery system of thermal power plant

Abstract

The utility model provides a boiler waste heat recovery system of a thermal power plant, which relates to the technical field of boiler waste heat recovery and is characterized in that a first butterfly valve is arranged on a hot air branch pipe, the boiler waste heat recovery system of the thermal power plant further comprises a hot air main pipe, the hot air branch pipe is communicated with the hot air main pipe, and a self-standing pressure reducing valve is arranged on the hot air main pipe. A wet electricity insulation box is arranged on the desulfurizing tower, the wet electricity insulation box is in through connection with the hot air main pipe through a distribution branch pipe, the distribution branch pipe is located between the self-standing pressure reducing valve and the wet electricity insulation box, and a second butterfly valve and a full-automatic temperature control pneumatic adjusting valve are arranged on the distribution branch pipe. The wet electric insulation box is heated through waste heat of the boiler, compared with a traditional mode that the wet electric insulation box is heated through electric heating equipment, a large amount of power consumption can be saved, the improvement cost is relatively low, energy conservation and emission reduction are facilitated, the power consumption expenditure of a factory is reduced, and the use effect is good.

Description

Technical Field

[0001] The utility model relates to the technical field of boiler waste heat recovery, in particular to a boiler waste heat recovery system in a thermal power plant. Background Art

[0002] The desulfurization tower wet electric heating furnace is a heating equipment designed to meet the requirements of the insulation box of the wet electric precipitator of the desulfurization tower in the thermal power plant to maintain the wet electric operating environment. Its function is to provide constant temperature heating for the operating environment inside the wet electric insulation box. The outdoor normal temperature ambient air is sent into the electric heating furnace chamber through its own blower, and the hot air is heated to the range of 60℃-120℃ after being powered on. The waste air after constant temperature heating enters the desulfurization tower and is taken away with the flue gas, thereby ensuring the normal operation of the high-voltage wet electric core equipment in the insulation box.

[0003] The existing wet electric heating furnace and its supporting blower consume electricity to generate hot air, and the cost of electricity resources is relatively high. When multiple furnaces are used at the same time, the power consumption cost increases significantly, which is not conducive to energy conservation and emission reduction, nor to economic benefits, and it is difficult to meet the needs of factory use. Utility Model Content

[0004] The utility model aims to provide a waste heat recovery system for a boiler in a thermal power plant, aiming to solve the problems mentioned in the above background technology.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: the waste heat recovery system of the boiler in the thermal power plant includes a plurality of boilers and desulfurization towers with the same number as the boilers, the boiler transports the flue gas to the desulfurization tower through the flue, the flue is provided with a dust collector, the boiler is provided with a hot air branch pipe, the hot air branch pipe is provided with a first butterfly valve, and also includes a hot air main pipe, the hot air branch pipe is connected with the hot air main pipe, the hot air main pipe is provided with a self-supporting pressure reducing valve, the desulfurization tower is provided with a wet electric insulation box, the wet electric insulation box and the hot air main pipe are connected through a distribution branch pipe, the distribution branch pipe is located between the self-supporting pressure reducing valve and the wet electric insulation box, and the distribution branch pipe is provided with a second butterfly valve and a fully automatic temperature-controlled pneumatic regulating valve.

[0006] Preferably, a first check valve is provided on the distribution branch pipe.

[0007] Preferably, it also includes an electric heating device, which is connected to the wet electrical insulation box.

[0008] Preferably, a second check valve is provided between the electric heating device and the wet electric insulation box.

[0009] The beneficial effects of the utility model are:

[0010] The system can effectively utilize the waste heat from the boiler and heat the wet electric insulation box through the waste heat from the boiler. Compared with the traditional method of heating the wet electric insulation box with electric heating equipment, it can save a lot of electricity and the transformation cost is relatively low. It is beneficial to energy conservation and emission reduction, reduces the factory's electricity consumption, and has a good use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of a specific embodiment of the utility model.

[0012] In the figure: 1. boiler; 2. desulfurization tower; 3. flue; 4. dust collector; 5. hot air branch pipe; 6. first butterfly valve; 7. hot air main pipe; 8. self-supporting pressure reducing valve; 9. wet electric insulation box; 10. distribution branch pipe; 11. second butterfly valve; 12. fully automatic temperature-controlled pneumatic regulating valve; 13. first check valve; 14. electric heating equipment; 15. second check valve. DETAILED DESCRIPTION

[0013] The specific implementation of the utility model is further described below in conjunction with the accompanying drawings.

[0014] like Figure 1 As shown, a waste heat recovery system for boilers in a thermal power plant comprises a plurality of boilers 1 and desulfurization towers 2 having the same number as the boilers 1. The boilers 1 transport flue gas to the desulfurization towers 2 through flues 3. A dust collector 4 is arranged on the flue 3. A hot air branch pipe 5 is arranged on the boiler 1. A first butterfly valve 6 is arranged on the hot air branch pipe 5. The hot air main pipe 7 is also included. The hot air branch pipe 5 is connected through the hot air main pipe 7. A self-supporting pressure reducing valve 8 is arranged on the hot air main pipe 7. A wet electric insulation box 9 is arranged on the desulfurization tower 2. The wet electric insulation box 9 is connected through the hot air main pipe 7 through a distribution branch pipe 10. The distribution branch pipe 10 is located between the self-supporting pressure reducing valve 8 and the wet electric insulation box 9. A second butterfly valve 11 and a fully automatic temperature-controlled pneumatic regulating valve 12 are arranged on the distribution branch pipe 10.

[0015] The waste heat at the tail of each boiler 1 enters into the hot air branch pipe 5, and the on-off of the hot air branch pipe 5 can be controlled by the first butterfly valve 6. When the first butterfly valve 6 is opened, the waste heat at the tail of all boilers 1 can be collected to the hot air main pipe 7 through the hot air branch pipe 5. The outlet end of the hot air main pipe 7 is arranged at the top of the desulfurization tower 2. The pressure at the outlet of the hot air main pipe 7 can be kept within the set range by the self-supporting pressure reducing valve 8. The hot air in the hot air main pipe 7 can enter into the distribution branch pipe 10 respectively. The on-off of the distribution branch pipe 10 can be controlled by the second butterfly valve 11 on the distribution branch pipe 10, so as to control whether the hot air is transported to the wet electric insulation box 9. At the same time, a group of fully automatic temperature-controlled pneumatic regulating valves 12 are set, and a temperature signal sensor is set inside the wet electric insulation box 9, so that the air volume can be automatically controlled according to the signal of the temperature signal sensor to achieve the purpose of heating and constant temperature. At the same time, the signal of the temperature signal sensor can be transmitted to the control room for remote monitoring.

[0016] Furthermore, a first check valve 13 is provided on the distribution branch pipe 10 to prevent reverse wind flow from increasing energy consumption.

[0017] Furthermore, it also includes an electric heating device 14, which is connected to the wet electric insulation box 9. The electric heating device 14 includes an electric heating furnace and a fan, so as to transport hot air to the wet electric insulation box 9. The method of heating the wet electric insulation box 9 by the waste heat of the boiler 1 is method one, and the method of heating the wet electric insulation box 9 by the electric heating device 14 is method two. Method two is a backup system. When it is necessary to inspect and maintain the various equipment of method one, the wet electric insulation box 9 can be heated by method two to prevent shutdown. After the inspection is completed, it is necessary to switch to method one.

[0018] Furthermore, a second check valve 15 is provided between the electric heating device 14 and the wet electric insulation box 9 to prevent reverse cross-flow and increase of energy consumption.

[0019] The exhaust temperature of the flue gas at the outlet of the rear end of the furnace is required to be no less than 130°C, which must be higher than the acid dew point. If the flue gas is directly discharged into the atmosphere after desulfurization and dust removal, a large amount of heat will be lost. The system can effectively utilize the waste heat of the boiler 1, and heat the wet electric insulation box 9 through the waste heat of the boiler 1. Compared with the traditional heating of the wet electric insulation box 9 through the electric heating equipment 14, a large amount of electricity consumption can be saved, and the transformation cost is relatively low, which is beneficial to energy conservation and emission reduction, and reduces the power consumption expenditure of the factory, and the use effect is good.

[0020] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A waste heat recovery system for a boiler in a thermal power plant, characterized in that: The invention comprises a plurality of boilers (1) and desulfurization towers (2) having the same number as the boilers (1), wherein the boilers (1) transport flue gas to the desulfurization towers (2) through flues (3), wherein the flues (3) are provided with dust collectors (4), wherein the boilers (1) are provided with hot air branch pipes (5), wherein the hot air branch pipes (5) are provided with first butterfly valves (6), and further comprising hot air main pipes (7), wherein the hot air branch pipes (5) are connected to the ... A self-supporting pressure reducing valve (8) is arranged on the hot air main pipe (7), a wet electric insulation box (9) is arranged on the desulfurization tower (2), the wet electric insulation box (9) and the hot air main pipe (7) are connected through a distribution branch pipe (10), the distribution branch pipe (10) is located between the self-supporting pressure reducing valve (8) and the wet electric insulation box (9), and a second butterfly valve (11) and a fully automatic temperature-controlled pneumatic regulating valve (12) are arranged on the distribution branch pipe (10).

2. The waste heat recovery system for a thermal power plant boiler according to claim 1 is characterized in that: The distribution branch pipe (10) is provided with a first check valve (13).

3. The waste heat recovery system for a thermal power plant boiler according to claim 1 is characterized in that: It also comprises an electric heating device (14), wherein the electric heating device (14) is connected to the wet electric insulation box (9).

4. The waste heat recovery system for a thermal power plant boiler according to claim 3 is characterized in that: A second check valve (15) is provided between the electric heating device (14) and the wet electric insulation box (9).

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