Comprehensive heating system for flue gas of power station

Abstract

The invention provides a power station flue gas comprehensive heating system used for a coal-fired power station, and relates to the technical field of flue gas heating. The system comprises a flue gas temperature adjusting assembly, a desulfurizing tower, a fused salt heating assembly and an electric heater, the flue gas temperature regulating assembly comprises a first flue gas temperature regulator and a second flue gas temperature regulator; the first flue gas temperature regulator is communicated with an inlet of the desulfurizing tower and the coal-fired power plant; an outlet of the desulfurization tower is connected with an inlet of the second flue gas temperature regulator, an inlet of the fused salt heating assembly and an inlet of the electric heater, and the desulfurization tower is configured to be only communicated with the inlet of the fused salt heating assembly when light exists, only communicated with the inlet of the electric heater and the inlet of the fused salt heating assembly when electricity is abandoned, and communicated with the outlet of the electric heater when light does not exist and electricity is abandoned. The first flue gas temperature regulator is communicated with the second flue gas temperature regulator. According to the comprehensive heating system for the flue gas of the power station, the efficiency is improved, light and abandoned electricity resources are fully utilized, and the energy consumption cost is reduced according to a photoelectric adjustment flue gas heating mode.

Description

Technical Field

[0001] This application relates to the technical field of flue gas heating, and particularly to a comprehensive heating system for power plant flue gas. Background Art

[0002] The flue gas generated by the boiler of a coal-fired power plant is in a wet-saturated state between 50 and 60 °C after desulfurization and is directly discharged through the chimney. This directly discharged flue gas has poor diffusion ability, is prone to accumulate near the chimney, causing the white smoke problem and polluting the environment. Moreover, the temperature of the flue gas is below the dew point, which is prone to cause acid compounds to condense in the flue gas, forming acid droplets that corrode the chimney, polluting the environment and causing low-temperature corrosion to the equipment. Therefore, it is necessary to heat the flue gas after desulfurization to increase the lifting height and diffusion ability of the clean flue gas, reduce the ground-level concentration of pollutants such as SO2, dust, and NO X etc., relieve the condensation phenomenon of the wet flue gas, alleviate the corrosion of the subsequent flue and chimney, and eliminate the phenomenon of white smoke from the clean flue gas chimney.

[0003] In the prior art, after flue gas desulfurization, a flue gas heater is added, that is, the original flue gas of the boiler is used to heat the desulfurized flue gas, so that the flue gas temperature is increased from 50 - 60 °C to about 80 °C and then discharged from the chimney.

[0004] However, due to the inherent defects of the flue gas heater, the inevitable leakage from the original flue gas side to the clean flue gas side reduces the desulfurization and heating efficiency, increasing the energy consumption cost. Summary of the Invention

[0005] This application provides a comprehensive heating system for power plant flue gas to solve the problems of insufficient heating treatment capacity and increased energy consumption cost of the existing flue gas heater.

[0006] This application provides a comprehensive heating system for power plant flue gas, which is used for coal-fired power plants and includes: a flue gas temperature adjustment component, a desulfurization tower, a molten salt heating component, and an electric heater;

[0007] The flue gas temperature adjustment component includes a first flue gas temperature regulator and a second flue gas temperature regulator. The first flue gas temperature regulator is used to connect the inlet of the desulfurization tower to the flue gas exhaust port of the coal-fired power plant, and the first flue gas temperature regulator is used to cool the flue gas discharged from the flue gas exhaust port;

[0008] The outlet of the desulfurization tower is connected to the inlet of the second flue gas temperature regulator, the inlet of the molten salt heating component, and the inlet of the electric heater. The outlet of the second flue gas temperature regulator, the outlet of the molten salt heating component, and the outlet of the electric heater are all used to connect to the chimney;

[0009] The desulfurization tower is configured such that when there is light, it is only connected to the inlet of the molten salt heating component; when there is surplus electricity, it is only connected to both the inlet of the electric heater and the inlet of the molten salt heating component; when there is no light and no surplus electricity, it is only connected to the inlet of the second flue gas temperature regulator.

[0010] In a possible implementation, for the integrated flue gas heating system provided in the present application, the desulfurization tower is respectively and sequentially connected to a second flue gas temperature regulator, a molten salt heating assembly, and an electric heater through flue ducts, and a photoelectric inductor and a plurality of control switches are provided on each flue duct;

[0011] The photoelectric inductor is used to detect light and surplus electricity. Each control switch is sequentially arranged at the outlet and inlet of each flue duct. The control switch is electrically connected to the photoelectric inductor, and the control switch controls the connection or disconnection of the flue duct where the control switch is located according to whether the photoelectric inductor detects light and surplus electricity.

[0012] In a possible implementation, the integrated flue gas heating system provided in the present application further includes a controller and a flowmeter. The flowmeter and the control switch are both electrically connected to the controller. The flowmeter is used to be arranged at the smoke exhaust port of the coal-fired power station to detect the flue gas flow discharged from the smoke exhaust port;

[0013] When the flue gas flow is greater than or equal to a predetermined value, the controller controls the control switch to open. When the flue gas flow is less than the predetermined value, the controller controls the control switch to close.

[0014] In a possible implementation, for the integrated flue gas heating system provided in the present application, the control switch is a flue gas baffle.

[0015] In a possible implementation, for the integrated flue gas heating system provided in the present application, an induced draft fan is arranged between the first flue gas temperature regulator and the desulfurization tower. The induced draft fan is connected to the first flue gas temperature regulator and the desulfurization tower through a flue duct, and a control switch is arranged between the induced draft fan and the desulfurization tower.

[0016] In a possible implementation, the integrated flue gas heating system provided in the present application further includes a dust collector. The inlet of the dust collector is connected to the outlet of the first flue gas temperature regulator, and the outlet of the dust collector is connected to the inlet of the induced draft fan to dust the flue gas flowing into the induced draft fan.

[0017] In a possible implementation, the first flue gas temperature regulator and the second flue gas temperature regulator of the integrated flue gas heating system provided in the present application are connected, and a control switch is arranged between them. By closing the control switch, heat exchange is enabled between the first flue gas temperature regulator and the second flue gas temperature regulator.

[0018] In a possible implementation, the molten salt heating assembly of the integrated flue gas heating system provided in the present application includes a molten salt heater, a molten salt hot tank, and a molten salt cold tank. The molten salt heater is connected to the desulfurization tower, and molten salt is provided in the molten salt heater. Both the molten salt hot tank and the molten salt cold tank are connected to the molten salt heater to enable the molten salt to exchange heat with the flue gas in the molten salt heater to increase the temperature.

[0019] In a possible implementation, for the integrated flue gas heating system of a power station provided by the present application, the molten salt heating assembly further includes a molten salt circulation pump, which is connected to the molten salt cold tank and the molten salt heater, so that the molten salt enters the molten salt cold tank after heat exchange in the molten salt heater.

[0020] In a possible implementation, for the integrated flue gas heating system of a power station provided by the present application, the molten salt heating assembly further includes a molten salt heating source, which includes ambient field heating and electric heating, and the ambient field heating and electric heating are connected in parallel at both ends of the molten salt hot tank and the molten salt cold tank.

[0021] An integrated flue gas heating system of a power station provided by the present application is used for a coal-fired power station and includes: a flue gas temperature adjustment assembly, a desulfurization tower, a molten salt heating assembly, and an electric heater; the flue gas temperature adjustment assembly includes a first flue gas temperature regulator and a second flue gas temperature regulator, and the first flue gas temperature regulator is connected to the desulfurization tower and the exhaust port of the coal-fired power station; the outlet of the desulfurization tower is connected to the inlets of the second flue gas temperature regulator, the molten salt heating assembly, and the electric heater, and the outlets of the second flue gas temperature regulator, the molten salt heating assembly, and the electric heater are all connected to the chimney; it is configured that when there is light, it is only connected to the inlet of the molten salt heating assembly, when there is abandoned electricity, it is only connected to the inlets of the electric heater and the molten salt heating assembly, and when there is no light and abandoned electricity, it is only connected to the inlet of the second flue gas temperature regulator. After the flue gas is cooled by the first flue gas temperature regulator, it enters the desulfurization tower for desulfurization. The desulfurized flue gas can adjust the flue gas to enter the second flue gas temperature regulator, the molten salt heating assembly, and the electric heater for heating according to the presence or absence of light and electricity, so that the flue gas can rise evenly from a lower temperature to a higher temperature that meets the emission temperature requirements, and the heated flue gas is discharged from the chimney; when there is light, the flue gas only enters the molten salt heating assembly for heating, when there is abandoned electricity, the flue gas only enters the electric heater and the molten salt heating assembly for heating, and when there is no light and abandoned electricity, the flue gas only enters the second flue gas temperature regulator for heating. This system adjusts the flue gas heating method according to light and electricity, makes full use of light and abandoned electricity resources, improves efficiency, and reduces energy consumption costs. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a schematic structural diagram of the integrated flue gas heating system of a power station provided by the embodiment of the present application;

[0024] Figure 2 It is a schematic structural diagram of the molten salt heating assembly in the integrated flue gas heating system of a power station provided by the embodiment of the present application;

[0025] Figure 3 This is a schematic structural diagram of an electric heater in the flue gas comprehensive heating system provided by the embodiments of the present application.

[0026] Explanation of reference numerals in the drawings:

[0027] 10 - Chimney;

[0028] 100 - Flue gas temperature adjustment component;

[0029] 110 - First flue gas temperature regulator;

[0030] 120 - Second flue gas temperature regulator;

[0031] 200 - Desulfurization tower;

[0032] 210 - Induced draft fan;

[0033] 300 - Molten salt heating component;

[0034] 310 - Molten salt heater;

[0035] 320 - Molten salt hot tank;

[0036] 330 - Molten salt cold tank;

[0037] 340 - Molten salt circulation pump;

[0038] 350 - Molten salt heating source; 351 - Environmental field heating; 352 - Electric heating;

[0039] 400 - Electric heater;

[0040] 500 - Control switch;

[0041] 510 - Photoelectric inductor;

[0042] 600 - Dust collector;

[0043] 700 - Flowmeter;

[0044] 800 - Controller.

[0045] Through the above drawings, the specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0046] Exemplary embodiments will be described in detail herein, and the embodiments are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims. Instead of all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts fall within the scope of protection of the present application.

[0047] It should be noted that in the description of the embodiments of the present application, the terms indicating the orientation or positional relationship such as "upper", "lower", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description, rather than indicating or implying that the device or component must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0048] In addition, it should be noted that the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0049] In the present application, unless otherwise clearly defined and limited, terms such as "installation", "connection", "fixation", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection or communication with each other; it may be a direct connection, or indirectly connected through an intermediate medium, and may be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0050] First, relevant concepts or terms involved in the present application will be explained.

[0051] Wasted electricity: It refers to the situation in a coal-fired power station where, due to the peak and valley demands in the power transmission and distribution process, especially during the valley period, electricity is not fully utilized and wasted.

[0052] GGH: It is an abbreviation for a gas-gas heater, generally used for heating flue gas.

[0053] FGD: It is the abbreviation of Flue gas desulfurization, representing flue gas desulfurization.

[0054] As described in the background art, if the wet saturated flue gas generated after desulfurization in a coal-fired power plant is directly discharged through a chimney, it is easy to accumulate near the chimney, forming white smoke and polluting the environment. Moreover, the temperature of the flue gas is below the dew point, and sulfides in the flue gas are likely to form acid droplets to corrode the chimney. Therefore, after flue gas desulfurization, it is necessary to heat the flue gas. In the prior art, after flue gas desulfurization, a flue gas heater is added to increase the temperature of the flue gas from 50 - 60 °C to about 80 °C and then discharge it from the chimney. However, the above flue gas heater directly heats the flue gas, resulting in serious corrosion of the heater, increasing the operation failures of the desulfurization system. Since two flue gas heaters need to be installed, the layout of the GGH and the supporting flue ducts increases, resulting in a large pressure loss. The increased pressure loss is close to one-third of the total pressure loss of the overall FGD. This part of the pressure loss needs to be overcome by increasing the head of the desulfurization booster fan, which will cause an increase in additional system operation costs. Moreover, due to the leakage defect of the flue gas heater itself, more heating time is required, reducing the desulfurization efficiency and heating efficiency. In addition, directly heating the flue gas easily causes the flue gas to quickly suspend and accumulate above the heating container, forming a pressure difference, resulting in uneven heating of the flue gas and requiring longer heating time, consuming more energy and having a large energy consumption cost.

[0055] Based on this, a comprehensive flue gas heating system for a power station provided in this application is used for a coal-fired power plant and includes: a flue gas temperature regulation component, a desulfurization tower, a molten salt heating component, and an electric heater; the flue gas temperature regulation component includes a first flue gas temperature regulator and a second flue gas temperature regulator. The first flue gas temperature regulator connects the desulfurization tower to the smoke exhaust port of the coal-fired power plant; the outlet of the desulfurization tower is connected to the inlets of the second flue gas temperature regulator, the molten salt heating component, and the electric heater. The outlets of the second flue gas temperature regulator, the molten salt heating component, and the electric heater are all connected to the chimney; the desulfurization tower is configured to be only connected to the inlet of the molten salt heating component when there is light, only connected to the inlets of the electric heater and the molten salt heating component when there is surplus electricity, and only connected to the inlet of the second flue gas temperature regulator when there is no light and surplus electricity. After the flue gas is cooled by the first flue gas temperature regulator and then enters the desulfurization tower for desulfurization, the desulfurized flue gas can be heated by adjusting the flue gas to enter the second flue gas temperature regulator, the molten salt heating component, and the electric heater according to the presence or absence of light and electricity, so that the flue gas can uniformly rise from a lower temperature to a higher temperature that meets the emission temperature requirements, and the heated flue gas is discharged from the chimney; when there is light, the flue gas only enters the molten salt heating component for heating, when there is surplus electricity, the flue gas only enters the electric heater and the molten salt heating component for heating, and when there is no light and surplus electricity, the flue gas only enters the second flue gas temperature regulator for heating. In the comprehensive flue gas heating system for a power station in the embodiments of this application, by adjusting the way of heating the flue gas according to light and electricity, the efficiency is improved, the light and surplus electricity resources are fully utilized, and the energy consumption cost is reduced.

[0056] The following will be combined with Figures 1 to 3 and specific embodiments to describe this application in detail. Figure 1Schematic structural diagram of the power plant flue gas comprehensive heating system provided by the embodiments of the present application; Figure 2 Schematic structural diagram of the molten salt heating component in the power plant flue gas comprehensive heating system provided by the embodiments of the present application; Figure 3 Schematic structural diagram of the electric heater in the power plant flue gas comprehensive heating system provided by the embodiments of the present application. In the embodiments of the present application, as Figure 1 shown, 10 represents the chimney, which will not be elaborated hereinafter.

[0057] The present application provides a power plant flue gas comprehensive heating system for a coal-fired power plant, including: a flue gas temperature adjustment component 100, a desulfurization tower 200, a molten salt heating component 300, and an electric heater 400; the flue gas temperature adjustment component 100 includes a first flue gas temperature regulator 110 and a second flue gas temperature regulator 120. The first flue gas temperature regulator 110 is used to connect the inlet of the desulfurization tower 200 to the flue gas outlet of the coal-fired power plant, and the first flue gas temperature regulator 110 is used to cool the flue gas discharged from the flue gas outlet. The outlet of the desulfurization tower 200 is connected to the inlet of the second flue gas temperature regulator 120, the inlet of the molten salt heating component 300, and the inlet of the electric heater 400. The outlets of the second flue gas temperature regulator 120, the molten salt heating component 300, and the electric heater 400 are all used to connect to the chimney; the desulfurization tower 200 is configured to be only connected to the inlet of the molten salt heating component 300 when there is light, only connected to both the inlet of the electric heater 400 and the inlet of the molten salt heating component 300 when there is surplus electricity, and only connected to the inlet of the second flue gas temperature regulator 120 when there is no light and no surplus electricity.

[0058] Specifically, the flue gas temperature adjustment component 100 includes a first flue gas temperature regulator 110 and a second flue gas temperature regulator 120. The flue gas outlet of the coal-fired power plant, the first flue gas temperature regulator 110, and the desulfurization tower 200 are connected in sequence. The inlet of the first flue gas temperature regulator 110 is connected to the flue gas outlet of the coal-fired power plant, and the first flue gas temperature regulator 110 is used to cool the flue gas discharged from the flue gas outlet. The second flue gas temperature regulator 120, the molten salt heating component 300, and the electric heater 400 are all used to heat and raise the temperature of the flue gas discharged from the desulfurization tower 200 to a higher temperature that meets the emission temperature requirements.

[0059] In order to heat and raise the temperature of the flue gas, the outlet of the desulfurization tower 200 is connected to the inlet of the second flue gas temperature regulator 120, the inlet of the molten salt heating component 300, and the inlet of the electric heater 400. The outlets of the second flue gas temperature regulator 120, the molten salt heating component 300, and the electric heater 400 are all used to connect to the chimney. By allowing the flue gas to enter the above inlets, it can uniformly rise from a lower temperature to a higher temperature that meets the emission temperature requirements, and the heated flue gas is discharged from the chimney.

[0060] Due to the sufficient optical and curtailment resources in the power station, in order to reduce the energy consumption cost of flue gas heating, when there is light, for example, during the day when the optical resources are sufficient, the desulfurization tower 200 is only connected to the inlet of the molten salt heating assembly 300 to enable the molten salt heating assembly 300 to heat the flue gas; when there is curtailment, for example, in the middle of the night when the curtailment resources are sufficient, the desulfurization tower 200 is connected to both the inlet of the electric heater 400 and the inlet of the molten salt heating assembly 300 to enable both the molten salt heating assembly 300 and the electric heater to heat the flue gas; when there is no light and no curtailment, for example, during peak hours in the morning and evening and during emergencies at night, the desulfurization tower 200 is only connected to the inlet of the second flue gas temperature regulator 120 to enable the second flue gas temperature regulator 120 to heat the flue gas.

[0061] The integrated flue gas heating system for a power station in the embodiment of the present application is used for a coal-fired power station and includes: a flue gas temperature regulation assembly 100, a desulfurization tower 200, a molten salt heating assembly 300, and an electric heater 400; the flue gas temperature regulation assembly 100 includes a first flue gas temperature regulator 110 and a second flue gas temperature regulator 120, and the first flue gas temperature regulator 110 connects the desulfurization tower 200 to the flue gas outlet of the coal-fired power station; the outlet of the desulfurization tower 200 is connected to the inlets of the second flue gas temperature regulator 120, the molten salt heating assembly 300, and the electric heater 400, and the outlets of the second flue gas temperature regulator 120, the molten salt heating assembly 300, and the electric heater 400 are all connected to the chimney; the desulfurization tower 200 is configured to be only connected to the inlet of the molten salt heating assembly 300 when there is light, to be only connected to both the inlet of the electric heater 400 and the inlet of the molten salt heating assembly 300 when there is curtailment, and to be only connected to the inlet of the second flue gas temperature regulator 120 when there is no light and no curtailment. After the flue gas is cooled by the first flue gas temperature regulator 110, it enters the desulfurization tower 200 for desulfurization. The desulfurized flue gas can be heated by adjusting whether it enters the second flue gas temperature regulator 120, the molten salt heating assembly 300, and the electric heater 400 according to the presence or absence of light and electricity, so that the flue gas can uniformly rise from a lower temperature to a higher temperature that meets the emission temperature requirements, and the heated flue gas is discharged from the chimney; when there is light, the flue gas only enters the molten salt heating assembly 300 for heating, when there is curtailment, the flue gas only enters the electric heater 400 and the molten salt heating assembly 300 for heating, and when there is no light and no curtailment, the flue gas only enters the second flue gas temperature regulator 120 for heating. The integrated flue gas heating system for a power station in the embodiment of the present application improves the efficiency by adjusting the way of heating the flue gas according to light and electricity, makes full use of optical and curtailment resources, and reduces the energy consumption cost.

[0062] In some embodiments, for the integrated power plant flue gas heating system provided by the present application, the desulfurization tower 200 is respectively and communicatively connected to the second flue gas temperature regulator 120, the molten salt heating assembly 300, and the electric heater 400 in sequence through flue ducts. Photoelectric sensors 510 and a plurality of control switches 500 are provided on each flue duct; the photoelectric sensors 510 are used to detect light and curtailment electricity. Each control switch 500 is sequentially arranged at the outlet and inlet of each flue duct. The control switch 500 is electrically connected to the photoelectric sensor 510. The control switch 500 controls the connection or disconnection of the flue duct where the control switch 500 is located according to whether the photoelectric sensor 510 detects light and curtailment electricity.

[0063] Specifically, flue ducts are connected in parallel at the outlet of the desulfurization tower 200. The desulfurization tower 200 is respectively and communicatively connected to the second flue gas temperature regulator 120, the molten salt heating assembly 300, and the electric heater 400 in sequence through flue ducts. Photoelectric sensors 510 and a plurality of control switches 500 are provided on each flue duct. The photoelectric sensors 510 can be used to detect light and curtailment electricity, mainly sensing ambient light signals and curtailment electricity signals transmitted from afar in the power grid. Control switches 500 are correspondingly arranged at the inlet and outlet of each flue duct. The disconnection or closure of the control switch 500 can disconnect or connect the flue duct where the control switch 500 is located.

[0064] In some embodiments, the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 can be designed according to actual situations as long as they can meet the flue gas chimney emission temperature. The present application places no restrictions on this. For example, the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 can adopt a flue gas heater GGH, and the specific type can be a regenerative GGH, a rotary type, or a split water medium type.

[0065] In addition, the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 can be integrally arranged or separately arranged in two parts. When the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 are integrally arranged, a switch is provided in the passage between the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 to realize the functions of cooling or heating through opening and closing; when the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 are separately arranged in two parts, they can be flexibly arranged according to the space size as long as the cooling or heating on one side can be realized.

[0066] When the photoelectric sensor 510 detects light and curtailment electricity, the control switches 500 of the flue ducts where the molten salt heating assembly 300 and the electric heater 400 are located are closed, and the corresponding flue ducts are connected. The molten salt heating assembly 300 and the electric heater 400 heat the flue gas, and the control switch 500 of the flue duct where the second flue gas temperature regulator 120 is located is opened, and the corresponding flue duct is disconnected.

[0067] When the photoelectric inductor 510 does not detect light and there is power outage, the control switch 500 of the flue where the molten salt heating assembly 300 and the electric heater 400 are located is disconnected, and the corresponding flue is disconnected; the control switch 500 of the flue where the second flue gas temperature regulator 120 is located is closed, and the corresponding flue is connected, and the second flue gas temperature regulator 120 heats the flue gas.

[0068] In some other embodiments, the power plant flue gas comprehensive heating system provided by the present application further includes a controller 800 and a flowmeter 700. The flowmeter 700 and the control switch 500 are both electrically connected to the controller 800. The flowmeter 700 is used to be arranged at the smoke exhaust port of the coal-fired power plant to detect the flue gas flow discharged from the smoke exhaust port; when the flue gas flow is greater than or equal to a predetermined value, the controller 800 controls the control switch 500 to open, and when the flue gas flow is less than the predetermined value, the controller 800 controls the control switch 500 to close.

[0069] Specifically, the flowmeter 700 is used to be arranged at the smoke exhaust port of the coal-fired power plant to detect the flue gas flow discharged from the power plant smoke exhaust port. The controller 800 is used to be electrically connected to the flowmeter 700 and the control switch 500. When the flowmeter 700 detects that the flue gas flow discharged from the smoke exhaust port is greater than or equal to the predetermined value, the controller 800 controls the control switch 500 to open, and when the flowmeter 700 detects that the flue gas flow discharged from the smoke exhaust port is less than the predetermined value, the controller 800 controls the control switch 500 to close.

[0070] Exemplarily, for the power plant flue gas comprehensive heating system provided by the present application, the control switch 500 is a flue gas baffle.

[0071] Specifically, the present application does not limit the driving form of the flue gas baffle. For example, it can be electric or pneumatic, as long as it can control the opening and closing of the corresponding flue. Exemplarily, the flue gas baffle can be driven by a motor. When the motor rotates forward, it controls the flue gas baffle to rotate and open the flue to allow the flue gas to flow through. When the motor rotates in reverse, it controls the flue gas baffle to rotate in the opposite direction to close the flue and prevent the flue gas from flowing through. Among them, the opening and closing angle of the flue gas baffle can also be controlled by controlling the rotation angle of the motor, such as 30 degrees, 45 degrees or 90 degrees. The baffle can be automatically adjusted according to different working conditions of the boiler and different flue gas flows passing through at different times. Exemplarily, the flue gas baffle can realize self-adjustment of opening and closing according to the controller 800, and realize automatic adjustment according to different flue gas flows passing through at different times detected by the flowmeter 700, and timely cut into the corresponding heater to work to ensure the smoothness of the flue gas flow path.

[0072] In some embodiments, a torque protection and a limit device are provided on the control switch 500 to extend the service life of the control switch 500.

[0073] In some embodiments, for the integrated flue gas heating system provided in the present application, an induced draft fan 210 is arranged between the first flue gas temperature regulator 110 and the desulfurization tower 200. The induced draft fan 210 is connected to the first flue gas temperature regulator 110 and the desulfurization tower 200 through a flue, and a control switch 500 is arranged between the induced draft fan 210 and the desulfurization tower 200.

[0074] Specifically, an induced draft fan 210 is arranged between the first flue gas temperature regulator 110 and the desulfurization tower 200. The inlet of the induced draft fan 210 is connected to the outlet of the first flue gas temperature regulator 110, and the outlet of the induced draft fan 210 is connected to the inlet of the desulfurization tower 200. The flue gas passes through the first flue gas temperature regulator 110 and the induced draft fan 210 in sequence.

[0075] and flows into the desulfurization tower 200.

[0076] Optionally, the integrated flue gas heating system provided in the present application further includes a dust collector 600. The inlet of the dust collector 600 is connected to the outlet of the first flue gas temperature regulator 110, and the outlet of the dust collector 600 is connected to the inlet of the induced draft fan 210 to remove dust from the flue gas flowing into the induced draft fan 210.

[0077] Specifically, a dust collector 600 is arranged between the first flue gas temperature regulator 110 and the induced draft fan 210. The dust collector 600 is used to remove dust from the flue gas. The flue gas passes through the first flue gas temperature regulator 110, the dust collector 600 and the induced draft fan 210 in sequence, and finally flows into the desulfurization tower 200.

[0078] In some other embodiments, for the integrated flue gas heating system provided in the present application, the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 are connected, and a control switch 500 is arranged therebetween. By closing the control switch 500, heat exchange is enabled between the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120.

[0079] Specifically, a control switch 500 is arranged between the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120. When the control switch 500 is closed, the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 are connected. At this time, heat exchange occurs between the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120. The first flue gas temperature regulator 110 is used for cooling, and the second flue gas temperature regulator 120 is used for heating.

[0080] When the control switch 500 is opened, the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 are disconnected, and heat exchange between the first flue gas temperature regulator 110 and the second flue gas temperature regulator 120 stops.

[0081] In some embodiments, for the integrated flue gas heating system of a power station provided in the present application, the molten salt heating assembly 300 includes a molten salt heater 310, a molten salt hot tank 320, and a molten salt cold tank 330. The molten salt heater 310 is communicated with the desulfurization tower 200. Molten salt is provided in the molten salt heater 310. Both the molten salt hot tank 320 and the molten salt cold tank 330 are communicated with the molten salt heater 310, so that the molten salt exchanges heat with the flue gas in the molten salt heater 310 to increase the temperature of the flue gas.

[0082] In specific implementation, the molten salt heating assembly 300 is communicated with the desulfurization tower 200 and is used to heat the flue gas flowing out of the desulfurization tower 200. The flue gas enters the molten salt heater 310. Molten salt is provided in the molten salt heater 310. The molten salt exchanges heat with the flue gas to increase the temperature of the flue gas. Both the molten salt hot tank 320 and the molten salt cold tank 330 are communicated with the molten salt heater 310. The molten salt hot tank 320 raises the temperature of the molten salt. After the molten salt exchanges heat with the flue gas in the molten salt heater 310, it enters the molten salt cold tank 330.

[0083] In the molten salt heating assembly 300 in the embodiments of the present application, since both the molten salt hot tank 320 and the molten salt cold tank 330 are communicated with the molten salt heater 310, heat exchange is performed to heat the flue gas, reducing heat loss and improving heating efficiency.

[0084] In some embodiments, the molten salt can adopt a low-temperature molten salt medium, and the operating temperature ranges from 60 to 150 °C. The present application does not limit this.

[0085] Among them, for the integrated flue gas heating system of a power station provided in the present application, the molten salt heating assembly 300 further includes a molten salt circulation pump 340. The molten salt circulation pump 340 is communicated with the molten salt cold tank 330 and the molten salt heater 310, so that the molten salt enters the molten salt cold tank 330 after heat exchange in the molten salt heater 310.

[0086] In specific implementation, the molten salt circulation pump 340 is arranged at the flue duct where the molten salt hot tank 320 is communicated with the molten salt heater 310 to provide power for the molten salt heat exchange circulation. The molten salt circulation pump 340 is communicated with the molten salt cold tank 330 and the molten salt heater 310. After the molten salt exchanges heat in the molten salt heater 310, it enters the molten salt cold tank 330 through the molten salt circulation pump 340.

[0087] In addition, for the integrated flue gas heating system of a power station provided in the present application, the molten salt heating assembly 300 further includes a molten salt heating source 350. The molten salt heating source 350 includes a field heating 351 and an electric heating 352. The field heating 351 and the electric heating 352 are connected in parallel at both ends of the molten salt hot tank 320 and the molten salt cold tank 330.

[0088] In specific implementation, the field heating 351 mainly uses a light source to provide heat for the molten salt heating assembly 300. Exemplarily, the field heating 351 can utilize the specular reflection of sunlight at the base to provide energy for the molten salt heating assembly 300. The electric heating 352 mainly relies on wasted electricity to provide energy for the molten salt heating assembly 300. The field heating 351 and the electric heating 352 are connected in parallel at both ends of the molten salt hot tank 320 and the molten salt cold tank 330. When there is sufficient sunlight during the day, the field heating 351 provides energy for the molten salt hot tank 320 and the molten salt cold tank 330, and the electric heating 352 is on standby; when there is no sunlight but there is wasted electricity at night, the electric heating 352 provides energy for the molten salt hot tank 320 and the molten salt cold tank 330 to consume the wasted electricity at the power station base. The field heating 351 and the electric heating 352 complement each other to save energy.

[0089] After considering the specification and practicing the invention disclosed herein, those skilled in the art will readily conceive of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and the embodiments are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the following claims.

[0090] It should be understood that the present application is not limited to the exact structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A comprehensive flue gas heating system for power stations, which is used in coal-fired power stations, is characterized in that, Including: A flue gas temperature regulation component (100), a desulfurization tower (200), a molten salt heating component (300), and an electric heater (400); The flue gas temperature regulation component (100) includes a first flue gas temperature regulator (110) and a second flue gas temperature regulator (120). The first flue gas temperature regulator (110) is used to connect the inlet of the desulfurization tower (200) to the smoke exhaust port of the coal-fired power station, and the first flue gas temperature regulator (110) is used to cool the flue gas discharged from the smoke exhaust port; The outlet of the desulfurization tower (200) is connected to the inlet of the second flue gas temperature regulator (120), the inlet of the molten salt heating component (300), and the inlet of the electric heater (400). The outlets of the second flue gas temperature regulator (120), the molten salt heating component (300), and the electric heater (400) are all used to connect to the chimney; The desulfurization tower (200) is configured to be only connected to the inlet of the molten salt heating component (300) when there is light, only connected to both the inlet of the electric heater (400) and the inlet of the molten salt heating component (300) when there is surplus electricity, and only connected to the inlet of the second flue gas temperature regulator (120) when there is no light and no surplus electricity.

2. The integrated flue gas heating system for power plants according to claim 1, wherein The desulfurization tower (200) is respectively connected to the second flue gas temperature regulator (120), the molten salt heating component (300), and the electric heater (400) through flue ducts in sequence. Photoelectric sensors (510) and a plurality of control switches (500) are arranged on each flue duct; The photoelectric sensors (510) are used to detect light and surplus electricity. Each control switch (500) is sequentially arranged at the outlet and inlet of each flue duct. The control switch (500) is electrically connected to the photoelectric sensor (510). The control switch (500) controls the connection or disconnection of the flue duct where the control switch (500) is located according to whether the photoelectric sensor (510) detects light and surplus electricity.

3. The integrated flue gas heating system for power plants according to claim 2, characterized in that, It further includes a controller (800) and a flowmeter (700). The flowmeter (700) and the control switch (500) are both electrically connected to the controller (800). The flowmeter (700) is used to be arranged on the smoke exhaust port of the coal-fired power station to detect the flow rate of the flue gas discharged from the smoke exhaust port; When the flue gas flow rate is greater than or equal to a predetermined value, the controller (800) controls the control switch (500) to open. When the flue gas flow rate is less than the predetermined value, the controller (800) controls the control switch (500) to close.

4. The integrated flue gas heating system for power plants according to claim 3, characterized in that, The control switch (500) is a flue gas baffle.

5. The integrated flue gas heating system for power plants according to any one of claims 1-4, characterized in that An induced draft fan (210) is arranged between the first flue gas temperature regulator (110) and the desulfurization tower (200). The induced draft fan (210) is connected to the first flue gas temperature regulator (110) and the desulfurization tower (200) through a flue duct. A control switch (500) is arranged between the induced draft fan (210) and the desulfurization tower (200).

6. The integrated flue gas heating system for power plants according to claim 5, characterized in that It further includes a dust collector (600), the inlet of the dust collector (600) is communicated with the outlet of the first flue gas temperature regulator (110), and the outlet of the dust collector (600) is communicated with the inlet of the induced draft fan (210) to remove dust from the flue gas flowing into the induced draft fan (210).

7. The integrated flue gas heating system for power plants according to claim 6, characterized in that The first flue gas temperature regulator (110) and the second flue gas temperature regulator (120) are communicated, and a control switch (500) is arranged between them. By closing the control switch (500), heat exchange is enabled between the first flue gas temperature regulator (110) and the second flue gas temperature regulator (120).

8. The integrated flue gas heating system for power plants according to any one of claims 1-4, characterized in that, The molten salt heating assembly (300) includes a molten salt heater (310), a molten salt hot tank (320), and a molten salt cold tank (330). The molten salt heater (310) is communicated with the desulfurization tower (200), and molten salt is arranged in the molten salt heater (310). Both the molten salt hot tank (320) and the molten salt cold tank (330) are communicated with the molten salt heater (310) to enable the molten salt to exchange heat with the flue gas in the molten salt heater (310) to increase the temperature.

9. The integrated flue gas heating system for power plants according to claim 8, wherein The molten salt heating assembly (300) further includes a molten salt circulation pump (340). The molten salt circulation pump (340) is communicated with the molten salt cold tank (330) and the molten salt heater (310) to enable the molten salt to enter the molten salt cold tank (330) after heat exchange in the molten salt heater (310).

10. The integrated flue gas heating system for power plants according to claim 9, wherein, The molten salt heating assembly (300) further includes a molten salt heating source (350). The molten salt heating source (350) includes a field heating (351) and an electric heating (352). The field heating (351) and the electric heating (352) are connected in parallel at both ends of the molten salt hot tank (320) and the molten salt cold tank (330).

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