Optimization system for thermal power denitration

Abstract

The utility model relates to the technical field of thermal power denitration, in particular to an optimization system for thermal power denitration. The system comprises an SCR reactor, a three-way pipeline and an electric denitration device, flue gas generated by thermal power is introduced into a gas inlet of the SCR reactor, a nitrogen oxide concentration sensor is arranged at a gas outlet of the SCR reactor, the gas outlet of the SCR reactor is communicated with a gas inlet of the three-way pipeline, the three-way pipeline comprises a switching device, a first gas outlet and a second gas outlet, the first gas outlet is communicated with the electric denitration device, and the second gas outlet is communicated with the electric denitration device. The switching device is used for opening and closing the first air outlet and the second air outlet; the electric denitration device comprises a complexing absorption bin, a reducing agent storage box and an electrode, the complexing absorption bin is used for containing a complexing agent, the reducing agent storage box is used for containing a reducing agent, the first gas outlet is communicated into the complexing absorption bin, the reducing agent storage box is communicated with the complexing absorption bin, and the electrode is arranged in the complexing absorption bin. The optimization system provided by the embodiment of the utility model can fully remove nitrogen oxides in the flue gas.

Description

Technical Field

[0001] The utility model relates to the technical field of thermal power denitration, in particular to an optimization system for thermal power denitration. Background Art

[0002] Thermal power plants produce flue gas, which contains nitrogen oxides. Nitrogen oxides discharged into the atmosphere will cause acid rain. Therefore, the flue gas needs to be denitrified before it is discharged into the atmosphere.

[0003] In the related art, a selective catalytic reduction (SCR) reactor is used to desulfurize flue gas. When denitrifying flue gas, the content of nitrogen oxides in the flue gas is not fixed. Accordingly, the amount of ammonia output in the SCR reactor needs to be adjusted in time according to the content of nitrogen oxides in the flue gas. However, the temperature in the SCR reactor is not fixed, and the reaction efficiency of catalytic reduction is also not fixed. Therefore, it will affect the effect of denitrification. If the denitrification is not thorough, some nitrogen oxides will still be discharged into the atmosphere with the flue gas.

[0004] Therefore, in view of the above-mentioned shortcomings, there is an urgent need for an optimized system for thermal power denitrification that can fully remove nitrogen oxides in flue gas. Utility Model Content

[0005] The embodiment of the utility model provides an optimization system for thermal power denitrification, which can fully remove nitrogen oxides in flue gas.

[0006] The utility model embodiment provides an optimization system for thermal power denitration, including an SCR reactor, a three-way pipeline and an electric denitration device;

[0007] The air inlet of the SCR reactor is fed with flue gas generated by thermal power generation, a nitrogen oxide concentration sensor is provided at the air outlet of the SCR reactor, the air outlet of the SCR reactor is connected to the air inlet of the three-way pipe, the three-way pipe comprises a switching device, a first air outlet and a second air outlet, the first air outlet is connected to the electric denitration device, and the switching device is used to open and close the first air outlet and the second air outlet;

[0008] The electric denitrification device includes a complex absorption bin, a reducing agent storage box and electrodes. The complex absorption bin is used to contain the complex agent, the reducing agent storage box is used to contain the reducing agent, the first gas outlet is connected to the complex absorption bin, the reducing agent storage box is connected to the complex absorption bin, and the electrode is arranged in the complex absorption bin.

[0009] In a possible design, the first gas outlet is connected to the complex absorption tank through a gas dispersion pipe, and the gas dispersion pipe includes a main pipe and multiple branch pipes. The main pipe is connected to the first gas outlet, one end of each of the branch pipes is connected to the main pipe, and the other end of each of the branch pipes is connected to the complex absorption tank.

[0010] In a possible design, the air outlet of each branch pipe is provided with an aeration device.

[0011] In a possible design, the outlets of the branch pipes are evenly distributed at different positions in the complexing absorption chamber.

[0012] In a possible design, the first air outlet is provided with a filter screen.

[0013] In a possible design, a controller is further included, which is electrically connected to the nitrogen oxide concentration sensor and the switching device respectively, and is used to control the switching device to open and close the first air outlet and the second air outlet according to concentration information collected by the nitrogen oxide concentration sensor.

[0014] In a possible design, the switching device includes a rotating shaft and a baffle, and the baffle is controlled to rotate by the rotating shaft to open and close the first air outlet and the second air outlet.

[0015] Compared with the prior art, the utility model has at least the following beneficial effects:

[0016] In this embodiment, the flue gas enters the SCR reactor for denitration, and the nitrogen oxide concentration sensor set at the outlet of the SCR reactor is used to test whether the nitrogen oxides in the flue gas treated are lower than the safe concentration. If the nitrogen oxide concentration of the flue gas discharged from the SCR reactor meets the standard, the first outlet is closed by the switching device, and the second outlet is opened, so that the flue gas is discharged from the second outlet; if the nitrogen oxide concentration of the flue gas discharged from the SCR reactor does not meet the standard, the second outlet is closed by the switching device, and the first outlet is opened, and the flue gas enters the complex absorption bin from the first outlet. The complex absorption bin is filled with a complexing agent for absorbing nitrogen oxides, for example, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, ferrous complexing agent or cobalt complexing agent. After the flue gas passes through the complexing agent, the nitrogen oxides are absorbed by the complexing agent, and the flue gas without nitrogen oxides is discharged from the complexing absorption bin. After the complexing agent absorbs nitrogen oxides, the reducing agent enters the complexing absorption bin from the reducing agent storage box. The reducing agent may include sulfite ions. The reducing agent and the complexing agent that absorbs nitrogen oxides undergo an oxidation-reduction reaction under the action of electrodes. Sulfite forms sulfate and nitrogen oxides form nitrogen gas and are discharged. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of a thermal power denitrification optimization system provided by an embodiment of the utility model.

[0019] In the figure:

[0020] 1-SCR reactor;

[0021] 2- Tee pipe;

[0022] 21-Switching device;

[0023] 3-complexation absorption chamber;

[0024] 4-Reducing agent storage tank;

[0025] 5-Electrode;

[0026] 6- Main pipeline;

[0027] 7-Pipeline

[0028] 8- Aeration device. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0030] In the description of the embodiments of the present utility model, unless otherwise clearly specified and limited, the terms "first" and "second" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "multiple" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense, for example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0031] In the description of this specification, it is necessary to understand that the directional words such as "upper" and "lower" described in the embodiments of the utility model are described at the angles shown in the drawings and should not be understood as limiting the embodiments of the utility model. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.

[0032] like Figure 1 As shown, the embodiment of the utility model provides an optimization system for thermal power denitration, including an SCR reactor 1, a three-way pipeline 2 and an electric denitration device;

[0033] The air inlet of the SCR reactor 1 is fed with flue gas generated by thermal power generation, and a nitrogen oxide concentration sensor is provided at the air outlet of the SCR reactor 1. The air outlet of the SCR reactor 1 is connected to the air inlet of the three-way pipe 2. The three-way pipe 2 includes a switching device 21, a first air outlet and a second air outlet. The first air outlet is connected to the electric denitration device, and the switching device 21 is used to open and close the first air outlet and the second air outlet.

[0034] The electric denitrification device includes a complex absorption bin 3, a reducing agent storage box and an electrode 5. The complex absorption bin 3 is used to contain the complex agent, the reducing agent storage box is used to contain the reducing agent, the first gas outlet is connected to the complex absorption bin 3, the reducing agent storage box 4 is connected to the complex absorption bin 3, and the electrode 5 is arranged in the complex absorption bin 3.

[0035] In this embodiment, the flue gas enters the SCR reactor 1 for denitration, and the nitrogen oxide concentration sensor arranged at the outlet of the SCR reactor 1 is used to test whether the nitrogen oxide concentration of the flue gas treated is lower than the safe concentration. If the nitrogen oxide concentration of the flue gas discharged from the SCR reactor 1 meets the standard, the first outlet is closed by the switching device 21, and the second outlet is opened, so that the flue gas is discharged from the second outlet; if the nitrogen oxide concentration of the flue gas discharged from the SCR reactor 1 does not meet the standard, the second outlet is closed by the switching device 21, and the first outlet is opened, and the flue gas enters the complexing absorption chamber 3 from the first outlet. The complexing absorption chamber 3 contains a complexing agent for absorbing nitrogen oxides, for example, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, ferrous complexing agent or cobalt complexing agent. After the flue gas passes through the complexing agent, the nitrogen oxides are absorbed by the complexing agent, and the flue gas without nitrogen oxides is discharged from the complexing absorption chamber 3. After the complexing agent absorbs nitrogen oxides, the reducing agent enters the complexing absorption chamber 3 from the reducing agent storage box. The reducing agent may include sulfite ions. The reducing agent and the complexing agent that absorbs nitrogen oxides undergo an oxidation-reduction reaction under the action of the electrode 5. The sulfite ions form sulfate ions, and the nitrogen oxides form nitrogen gas and are discharged.

[0036] It should be noted that both the second gas outlet and the electric denitrification device can be connected to other devices for subsequent treatment of the flue gas.

[0037] In some embodiments of the utility model, the first gas outlet is connected to the complex absorption tank 3 through a gas dispersion pipe, and the gas dispersion pipe includes a main pipe 6 and multiple branch pipes 7. The main pipe 6 is connected to the first gas outlet, one end of each branch pipe 7 is connected to the main pipe 6, and the other end of each branch pipe 7 is connected to the complex absorption tank 3.

[0038] In this embodiment, in order to increase the efficiency of the complexing agent in absorbing nitrogen oxides, a large amount of gas is discharged into the complexing absorption bin 3 through a plurality of branch pipes 7 , so that the flue gas is quickly and evenly distributed in the complexing absorption bin 3 .

[0039] In some embodiments of the present invention, an aeration device 8 is provided at the air outlet of each branch pipe 7. The aeration device 8 further improves the absorption rate of nitrogen oxides.

[0040] In some embodiments of the present invention, outlets of the branch pipes 7 are evenly distributed at different positions in the complexing absorption bin 3 .

[0041] In some embodiments of the utility model, the first air outlet is provided with a filter screen. The filter screen can filter solid dust in the smoke to prevent it from clogging the pipeline. The filter screen needs to be cleaned or replaced regularly.

[0042] In some embodiments of the present invention, a controller is further included. The controller is electrically connected to the nitrogen oxide concentration sensor and the switching device 21 respectively. The controller is used to control the switching device 21 to open and close the first air outlet and the second air outlet according to the concentration information collected by the nitrogen oxide concentration sensor.

[0043] In some embodiments of the present invention, the switching device 21 includes a rotating shaft and a baffle, and the baffle is controlled to rotate by the rotating shaft to open and close the first air outlet and the second air outlet. Of course, the switching device 21 can also be other electrically controlled or manually controlled valves.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. An optimization system for thermal power denitrification, characterized in that: It comprises an SCR reactor (1), a three-way pipeline (2) and an electric denitration device; The air inlet of the SCR reactor (1) is fed with flue gas generated by thermal power generation, a nitrogen oxide concentration sensor is arranged at the air outlet of the SCR reactor (1), the air outlet of the SCR reactor (1) is connected to the air inlet of the three-way pipe (2), the three-way pipe (2) comprises a switching device (21), a first air outlet and a second air outlet, the first air outlet is connected to the electric denitration device, and the switching device (21) is used to open and close the first air outlet and the second air outlet; The electric denitration device comprises a complex absorption chamber (3), a reducing agent storage box and an electrode (5); the complex absorption chamber (3) is used to contain a complex agent, the reducing agent storage box is used to contain a reducing agent, the first gas outlet is connected to the complex absorption chamber (3), the reducing agent storage box (4) is connected to the complex absorption chamber (3), and the electrode (5) is arranged in the complex absorption chamber (3).

2. The optimization system according to claim 1, characterized in that: The first gas outlet is connected to the complex absorption chamber (3) via a gas dispersion pipeline, and the gas dispersion pipeline comprises a main pipeline (6) and a plurality of branch pipelines (7). The main pipeline (6) is connected to the first gas outlet, one end of each of the branch pipelines (7) is connected to the main pipeline (6), and the other end of each of the branch pipelines (7) is connected to the complex absorption chamber (3).

3. The optimization system according to claim 2, characterized in that: The air outlet of each branch pipeline (7) is provided with an aeration device (8).

4. The optimization system according to claim 2, characterized in that: The outlets of the branch pipes (7) are evenly distributed at different positions in the complex absorption bin (3).

5. The optimization system according to claim 1, characterized in that: The first air outlet is provided with a filter screen.

6. The optimization system according to claim 1, characterized in that: It also includes a controller, which is electrically connected to the nitrogen oxide concentration sensor and the switching device (21) respectively, and is used to control the switching device (21) to open and close the first air outlet and the second air outlet according to concentration information collected by the nitrogen oxide concentration sensor.

7. The optimization system according to claim 1, characterized in that: The switching device (21) comprises a rotating shaft and a baffle, and the rotating shaft controls the baffle to rotate so as to open and close the first air outlet and the second air outlet.

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