SCR denitration ammonia escape precise control system

Abstract

The utility model discloses an accurate ammonia escape control system for SCR (Selective Catalytic Reduction) denitration, which relates to the technical field of SCR denitration and comprises a gas analysis system, a controller, an SCR reactor, an ammonia spraying device and a temperature detection device, the nitrogen oxide concentration value and the NH3 concentration value are sent to the controller; the temperature detection device is used for detecting the internal temperature of the SCR reactor and sending the internal temperature to the controller; the controller is used for controlling the ammonia spraying device according to the nitrogen oxide concentration value and the NH3 concentration value of the outlet of the SCR reactor and the internal temperature of the SCR reactor. According to the utility model, the ammonia spraying amount and the ammonia escape amount are accurately controlled within an allowable range, and the emission concentration of nitrogen oxides and the ammonia escape amount can be remotely transmitted to an enterprise central control system and an environment supervision department.

Description

Technical Field

[0001] The utility model relates to the technical field of SCR denitration, and in particular to an SCR denitration ammonia escape precision control system. Background Art

[0002] As the country's environmental protection requirements increase, how to reduce the emission of nitrogen oxides (NOx) has become an important part of the production process in the building materials industry. In this process, SCR (selective catalytic reduction) denitrification technology is generally used.

[0003] SCR denitrification technology is one of the most widely used denitrification technologies. It uses ammonia as a reducing agent to convert NOx into harmless nitrogen and water under the action of a catalyst. However, although SCR denitrification technology has a high efficiency in denitrification, its ammonia escape problem still exists. Ammonia escape not only reduces the denitrification efficiency, but may also cause ammonia leakage, causing secondary pollution, which brings great difficulties to the denitrification and control of nitrogen oxide emissions in the building materials industry. Utility Model Content

[0004] In view of the defects in the prior art, the utility model provides an SCR denitrification ammonia escape precision control system to solve the above technical problems.

[0005] A precise control system for SCR denitration ammonia escape comprises a gas analysis system, a controller, an SCR reactor, an ammonia spraying device, and a temperature detection device. The controller is electrically connected to the gas analysis system, the ammonia spraying device, the SCR reactor, and the temperature detection device; the gas analysis system is used to detect the nitrogen oxide concentration value and NH 3 concentration value, and the nitrogen oxide concentration value and NH 3 The concentration value is sent to the controller; the temperature detection device is used to detect the internal temperature of the SCR reactor and send the internal temperature to the controller; the controller is used to detect the nitrogen oxide concentration value and NH 3 The concentration value and the internal temperature of the SCR reactor control the ammonia injection device.

[0006] Preferably, the gas analysis system comprises a sampler and a gas analyzer, and the sampler is mechanically connected to the gas analyzer.

[0007] Preferably, the gas analyzer includes a nitrogen oxide concentration detection device and a NH 3 The nitrogen oxide concentration detection device can detect the nitrogen oxide concentration value at the outlet of the SCR reactor in real time to ensure the accuracy of the nitrogen oxide concentration detection at the outlet of the SCR reactor; the NH 3The concentration detection device is used to detect the NH 3 Concentration value.

[0008] Preferably, the temperature detection device is installed in the SCR reactor to ensure that the temperature in the reactor is within the range where the catalytic efficiency of the catalyst is the highest.

[0009] Preferably, the ammonia injection device includes a nozzle, which is made of corrosion-resistant and wear-resistant material and is arranged in the SCR reactor. The nozzle is also provided with a compressed air anti-blocking back-blowing system, which can effectively prevent the nozzle from being blocked and worn.

[0010] Preferably, the ammonia injection device comprises an ammonia injection variable frequency speed regulating pump, and the controller is configured to adjust the speed of the ammonia injection device according to the nitrogen oxide concentration value, NH 3 The concentration value and the internal temperature of the SCR reactor are used to adjust the speed of the ammonia injection speed regulating pump, and the ammonia injection amount of the SCR reactor is accurately controlled, thereby controlling the nitrogen oxide concentration and ammonia escape amount.

[0011] Preferably, the SCR denitration ammonia escape precision control system further includes a flow detection device connected to the ammonia injection device and the controller, and used to display the ammonia supply amount and the cumulative value of the ammonia injection amount. The controller can receive the instantaneous value of the flow detection device and the cumulative value of the ammonia injection amount in real time for display, which is convenient for operation and observation.

[0012] Preferably, the controller includes an alarm module. When the control system fails, the nitrogen oxide emissions and the ammonia escape exceed the standard, the alarm module can send out an alarm signal to promptly notify the central control system and the environmental supervision department.

[0013] Preferably, the controller further includes an input module, an output module, a power module, a CPU module, an HMI module and a communication module, and the controller is connected to a central control system and an environmental supervision department via an Ethernet network.

[0014] The beneficial effects of the utility model are embodied in:

[0015] The controller determines the nitrogen oxide concentration and NH 3 The ammonia injection device controls the ammonia injection amount by controlling the concentration and the internal temperature of the SCR reactor, ensuring accurate control of ammonia escape and nitrogen oxide emissions, and adopts a closed-loop mode with simple control and high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation of the utility model or the technical solution in the prior art, the following is a brief introduction to the drawings required for the specific implementation or the prior art description. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0017] Figure 1 This is the block diagram of the SCR reactor ammonia slip precision control system of the utility model;

[0018] Figure 2 This is a detailed structural diagram of the SCR reactor ammonia slip precision control system of the utility model. DETAILED DESCRIPTION

[0019] The following embodiments of the technical solution of the utility model are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.

[0020] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which the utility model belongs.

[0021] In Example 1:

[0022] like Figure 1 As shown, an SCR denitrification ammonia escape precision control system includes a gas analysis system, a controller, an SCR reactor, an ammonia injection device, a temperature detection device and a flow detection device, and the controller is electrically connected to the gas analysis system, the ammonia injection device, the SCR reactor, the temperature detection device and the flow detection device.

[0023] The gas analysis system includes a sampler and a gas analyzer, and the gas analyzer includes a nitrogen oxide concentration detection device, NH 3 The nitrogen oxide concentration detection device can detect the nitrogen oxide concentration value at the outlet of the SCR reactor in real time to ensure the accuracy of the nitrogen oxide concentration value detection at the outlet of the SCR reactor; the NH 3 The concentration detection device is used to detect the NH 3 Concentration value.

[0024] The temperature detection device is used to detect the internal temperature of the SCR reactor to ensure that the temperature in the reactor is within the range of the highest catalytic efficiency of the catalyst, and send the internal temperature to the controller. The controller detects the internal temperature of the SCR reactor according to the nitrogen oxide concentration value, NH 3 The concentration value and the internal temperature of the SCR reactor control the ammonia injection device, accurately control the amount of ammonia injection, and thus achieve the purpose of accurately controlling ammonia escape and nitrogen oxide emissions.

[0025] In this embodiment, the nozzle of the ammonia injection device is made of corrosion-resistant and wear-resistant material, is arranged in the SCR reactor, and is provided with a compressed air anti-blocking backblowing system to effectively prevent the nozzle from being blocked and worn.

[0026] Furthermore, the ammonia injection device includes a variable frequency ammonia injection pump, and the controller generates an ammonia injection pump according to the NH 3 The concentration detection device detects the NH 3 The concentration value adjusts the speed of the ammonia injection pump, thereby controlling the amount of ammonia supplied, preventing too little or too much ammonia injection, achieving precise control of the amount of ammonia injection inside the SCR reactor, and effectively controlling ammonia escape.

[0027] Furthermore, a flow detection device is connected to the ammonia injection device and the controller to display the cumulative value of the ammonia supply amount and the ammonia injection amount, and outputs the cumulative value of the ammonia supply amount and the ammonia injection amount to the controller in the form of an electrical signal for display, which is convenient for operation and observation.

[0028] It should be noted that the controller of the utility model application is the core of the control system. Figure 2 As shown, the controller includes an input module, an output module, a power module, a CPU module, an HMI module and a communication module to complete the precise control function of ammonia escape. The operator can operate on the controller, or transmit the operating status of the denitrification ammonia escape precise control system and the ammonia escape amount and nitrogen oxide emissions to the enterprise central control system and environmental supervision department in real time through the Ethernet network.

[0029] From the above description, it can be known that the ammonia escape precise control system of the utility model adopts closed-loop control to ensure precise control of the ammonia escape amount and nitrogen oxide emissions at the outlet of the SCR reactor. The control is simple and the precision is high, which greatly saves manpower and is conducive to the precise and stable operation of the system.

[0030] In addition, the utility model is used for the precise control system of ammonia escape from denitrification in the building materials industry. The controller is the core, and the operating status of the control system is displayed on the controller in real time, and transmitted to the enterprise's central control system and environmental supervision department, ensuring the precise and stable operation of the control system.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model, and they should all be included in the scope of the claims and specification of the utility model.

Claims

1. An SCR denitrification ammonia escape precision control system, characterized by: It includes a gas analysis system, a controller, an SCR reactor, an ammonia injection device, and a temperature detection device. The controller is electrically connected to the gas analysis system, the ammonia injection device, the SCR reactor, and the temperature detection device; the gas analysis system is used to detect the nitrogen oxide concentration value and the NH3 concentration value at the outlet of the SCR reactor, and send the nitrogen oxide concentration value and the NH3 concentration value to the controller; the temperature detection device is used to detect the internal temperature of the SCR reactor, and send the internal temperature to the controller; The controller controls the ammonia injection device according to the nitrogen oxide concentration value and the NH3 concentration value at the outlet of the SCR reactor and the internal temperature of the SCR reactor.

2. The SCR denitrification ammonia escape precise control system according to claim 1 is characterized by: The gas analysis system comprises a sampler and a gas analyzer, wherein the sampler is mechanically connected to the gas analyzer.

3. The SCR denitrification ammonia escape precise control system according to claim 2 is characterized by: The gas analyzer includes a nitrogen oxide concentration detection device and an NH3 concentration detection device; the nitrogen oxide concentration detection device is electrically connected to the controller and is used to detect the nitrogen oxide concentration value at the outlet of the SCR reactor in real time; the NH3 concentration detection device is electrically connected to the controller and is used to detect the NH3 concentration value at the outlet of the SCR reactor.

4. The SCR denitrification ammonia escape precise control system according to claim 1, characterized in that: The temperature detection device is installed in the SCR reactor.

5. The SCR denitrification ammonia escape precise control system according to claim 1 is characterized by: The ammonia injection device comprises a nozzle, which is arranged in the SCR reactor, and the nozzle is provided with a compressed air anti-blocking back-blowing system.

6. The SCR denitrification ammonia escape precise control system according to claim 5, characterized in that: The nozzle is made of corrosion-resistant and wear-resistant material.

7. The SCR denitrification ammonia escape precise control system according to claim 5, characterized in that: The ammonia injection device also includes an ammonia injection variable frequency speed regulating pump, and the controller adjusts the speed of the ammonia injection speed regulating pump according to the nitrogen oxide concentration value, the NH3 concentration value and the internal temperature of the SCR reactor.

8. The SCR denitrification ammonia escape precise control system according to claim 1, characterized in that: It also includes a flow detection device, which is connected to the ammonia injection device and the controller, and is used to display the cumulative value of the ammonia supply amount and the ammonia injection amount, and output the cumulative value of the ammonia supply amount and the ammonia injection amount to the controller in the form of an electrical signal for display.

9. The SCR denitrification ammonia escape precise control system according to claim 1, characterized in that: The controller includes an alarm module for sending out an alarm signal to promptly notify the central control system and the environmental supervision department when a control system failure occurs, the nitrogen oxide emission and the ammonia escape exceed the standard.

10. The SCR denitrification ammonia escape precise control system according to claim 9, characterized in that: The controller also includes an input module, an output module, a power module, a CPU module, an HMI module and a communication module. The controller is connected to a central control system and an environmental supervision department via an Ethernet network.

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