Accurate ammonia spraying denitration device

Abstract

The utility model discloses an accurate ammonia injection denitration device, including mixing pipe, electrically operated valve, measure and control instrument, the gas outlet of mixing pipe is equipped with first ammonia concentration sensor, the middle part of mixing pipe is equipped with a plurality of central pipe, and central pipe is connected with the nozzle, and the deflector is installed between central pipe and mixing pipe, and the deflector is equipped with the first ammonia concentration sensor and the second ammonia concentration sensor. The spray heads are arranged around the flow guide plate in a layered mode, the flow guide plate is used for flow mixing of atomized ammonia water and nitric oxide, the electric valves are communicated with the center pipe and connected with a liquid supply pump, and the measurement and control instrument is electrically connected with the first ammonia concentration sensor, the electric valves and the liquid supply pump. Ammonia water becomes mist through the spray head, nitrogen oxide spirally flows along the flow guide plate when flowing in the mixing pipe, the flowing path of the nitrogen oxide is prolonged, the contact time of the nitrogen oxide and the ammonia water is prolonged, and the mist ammonia water and the nitrogen oxide are fully mixed through the spiral flow channel.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of denitration, specifically to a precise ammonia spraying denitration device. BACKGROUND

[0002] Nitrogen oxide is one of air pollutants, which has negative effects on the environment and human health. Ammonia water denitration is one of the common methods. By spraying ammonia water into flue gas, ammonia reacts with nitrogen oxide to generate nitrogen and water, thereby achieving the purpose of reducing nitrogen oxide emissions.

[0003] In related technology, through retrieval, it is found that the scheme of a kind of ammonia spraying structure for ammonia water denitration (publication number CN221964925U) is installed with equipment main pipe below preparation bucket, one end of equipment main pipe is connected with air compression pipe, and air compression valve is installed in the middle of air compression pipe, air compression valve can discharge the gas of ammonia water in the process of flowing out, reduce the resistance of ammonia water flowing out, also can control the output pressure of ammonia water, and air compression valve is connected by connecting pipe and flow control pipe, flow control valve is arranged in the middle of flow control pipe, flow control valve can further control the flow of ammonia water, so as to realize the precise control of ammonia water flow.

[0004] However, the above scheme sprays ammonia water through annularly arranged gun nozzles, so that ammonia water contacts with nitrogen oxide. Since nitrogen oxide flows linearly in the pipeline, the mixing effect of ammonia water and nitrogen oxide is poor, and nitrogen oxide cannot be fully mixed, which affects the denitration effect. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a precise ammonia spraying denitration device to solve the problems in the above background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a precise ammonia spraying denitration device, comprising a mixing pipe, a first ammonia gas concentration sensor is installed at the gas outlet of the mixing pipe, a plurality of center pipes are installed in the middle of the mixing pipe, and the center pipes are connected with spray heads, a guide vane is installed between the center pipes and the mixing pipe, the spray heads are arranged in layers around the guide vane, the guide vane is used for the flow mixing of fog state ammonia water and nitrogen oxide, and nitrogen oxide can be fully mixed when flowing, which is beneficial to the rapid removal of nitrogen oxide, and the nitrogen oxide purification efficiency is high.

[0007] An electric valve is provided and communicates with the center pipes, and the electric valve is connected with a liquid supply pump.

[0008] A measurement and control device is electrically connected with the first ammonia gas concentration sensor, the electric valve and the liquid supply pump, and controls the opening of the electric valve to realize the spraying amount of ammonia water and avoid the waste of ammonia water.

[0009] Further, the mixing pipe is connected with an SCR reactor, a second ammonia concentration sensor and two thermometers are installed on the SCR reactor, and the second ammonia concentration sensor and the thermometers are electrically connected with the controller, and the SCR reactor can catalyze the rapid reaction of ammonia water and nitrogen oxide, and improve the processing efficiency of nitrogen oxide.

[0010] Further, the liquid supply pump is connected with a liquid supply tank, and the liquid supply tank is provided with a liquid level meter electrically connected with the controller, and the controller is electrically connected with an air compressor, and the air compressor is communicated with the electric valve, so that the ammonia water extracted by the liquid supply pump is fully atomized by compressed air, and the ammonia water is fully contacted with the nitrogen oxide, and the nitrogen oxide processing is more thorough.

[0011] Compared with the prior art, the utility model has the advantages that:

[0012] (1) The ammonia water is changed into mist state through the spray head, the nitrogen oxide flows along the spiral flow guide plate in the mixing pipe, the flow path of the nitrogen oxide is prolonged, the contact time with the ammonia water is increased, and the mist state ammonia water and the nitrogen oxide are fully mixed through the spiral flow channel.

[0013] (2) The controller detects the consumption of ammonia gas through the first ammonia concentration sensor and the first ammonia concentration sensor, controls the opening degree of the electric valve, adjusts the injection amount of ammonia water, ensures that the nitrogen oxide can be completely removed, prevents the excessive waste of ammonia water, and realizes the best nitrogen oxide removal efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is the schematic diagram of the utility model as a whole;

[0015] Figure 2 It is the structural schematic diagram of the mixing pipe inside the utility model;

[0016] Figure 3 It is the schematic diagram of the mixing pipe and the flow guide plate connection of the utility model;

[0017] Figure 4 It is the sectional view of the center pipe of the utility model.

[0018] In the drawing: 1, controller; 2, liquid supply pump; 3, liquid supply tank; 4, liquid level meter; 5, SCR reactor; 6, thermometer; 7, air compressor; 8, first ammonia concentration sensor; 9, second ammonia concentration sensor; 10, mixing pipe; 11, extension pipe; 12, electric valve; 13, center pipe; 14, spray head; 15, flow guide plate; 16, plugging plate. DETAILED DESCRIPTION

[0019] Clearly, the described embodiments are merely a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0020] Embodiments:

[0021] Please refer to Figures 1-4 The present application provides a technical scheme: a precise ammonia spraying denitration device, comprising a mixing pipe 10, a first ammonia concentration sensor 8 is installed at the gas outlet of the mixing pipe 10, the inside of the mixing pipe 10 is in a high-temperature state, so that the fog state of ammonia water becomes ammonia gas in the flowing process, and the first ammonia concentration sensor 8 can detect the ammonia concentration discharged from the mixing pipe 10.

[0022] A plurality of center pipes 13 are installed in the middle of the mixing pipe 10, and the center pipes 13 are connected with spray heads 14, flow guides 15 are installed between the center pipes 13 and the mixing pipe 10, a plurality of spray heads 14 are arranged in layers around the flow guides 15, the flow guides 15 are used for the flow mixing of the fog state of ammonia water and nitrogen oxides, prolong the mixing time of the fog state of ammonia water and nitrogen oxides, realize the full mixing of nitrogen oxides and ammonia water, and the spray heads 14 are arranged in a straight line along the center pipes 13, so as to provide sufficient ammonia water for the nitrogen oxides.

[0023] The electric valve 12 is provided with a plurality of electric valves 12 and is communicated with the center pipes 13, and the electric valve 12 is connected with a liquid supply pump 2, the opening degree of the electric valve 12 is controlled by the measuring and controlling device 1, the electric valve 12 is controlled according to the ammonia water demand, so as to avoid the ammonia water shortage and prevent the ammonia water excess.

[0024] The measuring and controlling device 1 is electrically connected with the first ammonia concentration sensor 8, the electric valve 12 and the liquid supply pump 2, the opening of the electric valve 12 and the liquid supply pump 2 is controlled by the measuring and controlling device 1, the measuring and controlling device 1 can adopt a Siemens S7 series PLC (such as S7-1200 or S7-1500), which has data processing capability, high-speed communication interface and rich I / O module, and can meet the requirement of precise ammonia spraying.

[0025] In the present embodiment, as Figure 1As shown, the mixing pipe 10 is connected with an SCR reactor 5, which is a catalytic reduction reactor, ammonia (NH3) is sprayed into high-temperature flue gas as a reducing agent to chemically react with nitrogen oxides (NOx) in the flue gas to convert it into harmless nitrogen (N2) and water (H2O), the SCR reactor 5 is provided with a second ammonia concentration sensor 9 and two thermometers 6, and the second ammonia concentration sensor 9 and the thermometers 6 are electrically connected with the controller 1, the thermometer 6 detects the temperature of the SCR reactor 5 to ensure that the SCR catalyst works in a suitable temperature range, and the second ammonia concentration sensor 9 detects whether the gas discharged from the SCR reactor 5 contains ammonia.

[0026] In this embodiment, as shown in Figure 4 several central pipes 13 are connected up and down, and the connection of the central pipe 13 is provided with a blocking plate 16, so that ammonia water is sprayed all the time when nitrogen oxides flow in the mixing pipe 10, providing sufficient ammonia water for nitrogen oxides.

[0027] In this embodiment, as shown in Figure 2 the central pipe 13 is connected with an extension pipe 11 on the side, and the extension pipe 11 passes through the mixing pipe 10, the electric valve 12 is connected with the extension pipe 11, when the electric valve 12 fails, the electric valve 12 can be separated from the extension pipe 11, which is convenient for replacing and repairing the electric valve 12.

[0028] In this embodiment, as shown in Figure 1 the liquid supply pump 2 is connected with a liquid supply tank 3, and the liquid supply tank 3 is provided with a liquid level meter 4 electrically connected with the controller 1, the liquid level meter 4 sends the remaining amount of ammonia water in the liquid supply tank 3 to the controller 1 in the form of an electric signal, when the liquid level is lower than the preset value, the controller 1 sends an alarm, and the ammonia water can be supplemented in time.

[0029] In this embodiment, as shown in Figure 1 the controller 1 is electrically connected with an air compressor 7, the air compressor 7 communicates with the electric valve 12, by increasing the pressure of the ammonia water sprayed from the nozzle 14 through the air compressor 7, the ammonia water can be fully atomized to ensure that the contact area between the ammonia water and the nitrogen oxides is large.

[0030] In this embodiment, as shown in Figure 2 and Figure 3 the guide vane 15 is spirally arranged, and the guide vane 15 is sealingly connected with the mixing pipe 10 and the central pipe 13, the flowing nitrogen oxides drive the ammonia water to flow spirally, prolonging the contact time between the nitrogen oxides and the ammonia water, and mixing uniformly and completely.

[0031] In this embodiment, as shown in Figure 2 and Figure 3As shown, the spray heads 14 are arranged annularly in layers around the central pipe 13, preventing the spray heads 14 from touching the flow guide plates 15, and the spray direction of the spray heads 14 is the same as the flow direction of the nitrogen oxides, so that the ammonia water droplets can better contact and mix with the nitrogen oxides, thereby increasing the collision frequency and reaction opportunities between the reactants.

[0032] Specifically, in use, when the nitrogen oxides flow into the mixing pipe 10, the spiral flow guide plates 15 make the nitrogen oxides flow in a spiral path, the liquid supply pump 2 draws the ammonia water in the liquid supply tank 3 and sends it into the central pipe 13 through the electric valve 12 and the extension pipe 11, and the air compressor 7 also sends compressed air into the central pipe 13, increasing the pressure of the ammonia water, so that the ammonia water is sprayed from the spray heads 14 to form a mist state, and the mist state ammonia water spirally flows with the nitrogen oxides and is fully mixed in the process of flowing, and because the mixing pipe 10 is in a high-temperature state, the mist state ammonia water becomes ammonia gas and is fully mixed with the nitrogen oxides;

[0033] The ammonia gas and the nitrogen oxides enter the SCR reactor 5, in which the ammonia gas acts as a reducing agent and chemically reacts with the nitrogen oxides in the flue gas under the action of the catalyst, and these reactions can efficiently decompose the nitrogen oxides into nitrogen and water under appropriate catalysts and temperature conditions, thereby significantly reducing the content of the nitrogen oxides in the flue gas and meeting the requirements of environmental protection emission, and the two thermometers 6 detect the temperature of the SCR reactor 5 to ensure that the temperature in the SCR reactor 5 is in a suitable state;

[0034] The first ammonia gas concentration sensor 8 detects the ammonia gas concentration of the mixing pipe 10, the second ammonia gas concentration sensor 9 detects the concentration of the ammonia gas after consumption, and the controller 1 adjusts the opening degree of the electric valve 12 based on the ammonia gas concentration difference, if the ammonia gas concentration of the SCR reactor 5 exceeds the standard, the opening degree of the electric valve 12 is reduced to avoid waste of the ammonia water, and if the ammonia gas concentration is lower than the threshold value, the opening degree of the electric valve 12 is increased, and the best nitrogen oxide removal efficiency is realized by adjusting the ammonia water injection amount.

[0035] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A precise ammonia injection denitration device, characterized in that, Include: Mixing pipe (10), the first ammonia concentration sensor (8) is installed to the gas outlet of the mixing pipe (10), a plurality of center pipes (13) are installed in the mixing pipe (10), and the center pipe (13) is connected with the spray head (14), the guide vane (15) is installed between the center pipe (13) and the mixing pipe (10), a plurality of spray heads (14) are arranged in layers around the guide vane (15), and the guide vane (15) is used for the flow mixing of ammonia water and nitrogen oxide in mist state; Electric valve (12), a plurality of electric valves (12) are arranged and communicated with the center pipe (13), and the electric valve (12) is connected with the liquid supply pump (2); The measuring controller (1) is electrically connected with the first ammonia concentration sensor (8), the electric valve (12), the liquid supply pump (2).

2. The precise ammonia injection denitration device according to claim 1, characterized in that: The mixing pipe (10) is connected with the SCR reactor (5), the second ammonia concentration sensor (9) and two thermometers (6) are installed on the SCR reactor (5), and the second ammonia concentration sensor (9) and the thermometer (6) are electrically connected with the measuring controller (1).

3. The device according to claim 1, characterized in that: A plurality of center pipes (13) are connected up and down, and the connecting part of the center pipe (13) is provided with a blocking plate (16).

4. The precise ammonia injection denitration device according to claim 1, characterized in that: The center pipe (13) is connected with the extension pipe (11) on the side, and the extension pipe (11) passes through the mixing pipe (10), and the electric valve (12) is connected with the extension pipe (11).

5. The precise ammonia injection denitration device according to claim 1, characterized in that: The liquid supply pump (2) is connected with the liquid supply tank (3), and the liquid supply tank (3) is provided with the liquid level meter (4) electrically connected with the measuring controller (1).

6. The precise ammonia injection denitration device according to claim 1, characterized in that: The measuring controller (1) is electrically connected with the air compressor (7), and the air compressor (7) is communicated with the electric valve (12).

7. The precise ammonia injection device for denitration according to claim 1, characterized in that: The guide vane (15) is arranged in spiral shape, and the guide vane (15) is sealingly connected with the mixing pipe (10) and the center pipe (13).

8. The precise ammonia injection device for denitration according to claim 1, characterized in that: The spray head (14) is arranged in annular layers around the center pipe (13), and the spray head (14) is arranged in the same direction as the nitrogen oxide flow direction.

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