Ammonia gas leakage monitoring device for denitration system of thermal power plant

Abstract

An ammonia gas leakage monitoring device of a denitration system of a thermal power plant comprises a gas collecting hood, an exhaust fan, an ammonia gas detector and a centralized control terminal, the gas collecting hood is arranged right above the denitration system and is used for collecting leaked ammonia gas; an inlet pipeline of the exhaust fan is mounted at the top of the gas collecting hood and is used for forming negative pressure suction in the gas collecting hood; the ammonia gas detector is mounted on an outlet pipeline of the exhaust fan and is used for detecting the concentration of ammonia gas; and the centralized control terminal is electrically connected with the ammonia gas detector and is used for monitoring and displaying the monitored ammonia gas concentration value. According to the utility model, leaked ammonia gas can be gathered, sucked by the exhaust fan and then fed into the ammonia gas detector to monitor the concentration value of the ammonia gas, and the concentration value of the ammonia gas is sent to the display terminal to be displayed, so that workers can know the leakage condition of the ammonia gas in time, take preventive measures in time, eliminate the hidden danger of leakage points of the device in time, and guarantee the normal operation of a denitration system.

Description

Technical Field

[0001] This utility model relates to an ammonia leakage monitoring device, and more particularly to an ammonia leakage monitoring device for a denitrification system in a thermal power plant. Background Technology

[0002] The ammonia supply regulating unit is a crucial component of the denitrification system in thermal power plants. Many factors can affect its operation, such as equipment malfunction and ammonia leakage. Ammonia leakage is a significant reason why the regulating unit cannot be put into operation. Currently, the primary method for monitoring ammonia leakage in thermal power plants involves installing two ammonia concentration alarms above the regulating unit.

[0003] When monitoring the ammonia concentration leaking from the ammonia supply regulating device in the denitrification system of a thermal power plant, the ammonia leaking from various leak points is dispersed by the airflow due to the relatively open space above the device. The ammonia concentration alarm cannot accurately collect the ammonia emitted from the leak point. As a result, the ammonia concentration alarm cannot issue a timely and accurate ammonia leak alarm signal when the ammonia leaks in the early stage. When a large amount of ammonia leaks to a certain concentration, a leak alarm signal is issued, and the staff loses the best time to deal with the fault. In severe cases, it can lead to the shutdown of the ammonia supply regulating device, posing a major hidden danger to the normal operation of the denitrification system. Utility Model Content

[0004] To address the aforementioned problems, this utility model proposes an ammonia leakage monitoring device for a denitrification system in a thermal power plant. The specific technical solution is as follows:

[0005] A device for monitoring ammonia leakage in a denitrification system of a thermal power plant, comprising:

[0006] A gas collection hood is installed directly above the denitrification system to collect leaked ammonia gas.

[0007] The exhaust fan has its inlet pipe installed at the top of the air collection hood to create negative pressure and draw air into the air collection hood.

[0008] An ammonia detector, installed on the outlet pipe of the exhaust fan, is used to detect the ammonia concentration; and

[0009] The central control terminal is electrically connected to the ammonia detector to monitor and display the monitored ammonia concentration value.

[0010] Furthermore, two sets of exhaust fans are provided, and ammonia detectors are installed on the outlet pipes of both sets of exhaust fans.

[0011] Furthermore, the inlet pipes of the two exhaust fans are connected to the gas collection hood via three-way valves.

[0012] Furthermore, it also includes valve assemblies to allow each of the two exhaust fans to be connected to either ammonia detector.

[0013] Furthermore, the valve group includes multiple shut-off valves, which are respectively installed on the outlet pipes of the two sets of exhaust fans and the inlet pipes of the two ammonia detectors.

[0014] Furthermore, the three-way valve and the shut-off valve are manual valves or electric valves.

[0015] Furthermore, the centralized control terminal has a built-in control program that enables any ammonia detector to connect to any exhaust fan via the control of an electric valve.

[0016] Furthermore, the centralized control terminal is equipped with a display terminal for displaying the device flowchart and operating status screen.

[0017] Furthermore, the ammonia detector is electrically connected to an audible and visual alarm, which is installed on a platform near the ammonia supply pipeline of the denitrification system.

[0018] Furthermore, the gas collection hood is umbrella-shaped.

[0019] Beneficial effects:

[0020] This invention can collect leaked ammonia gas and then draw it into an ammonia detector via a fan to monitor the ammonia concentration. The data is then displayed on a terminal, allowing staff to promptly understand the ammonia leak situation, take preventative measures, eliminate potential leaks, and ensure the normal operation of the denitrification system. Furthermore, the device features four manually and automatically switchable operating modes to ensure continuous monitoring data and reduce the risk of monitoring interruptions due to equipment failure. Attached Figure Description

[0021] Figure 1 This is a simplified planar flow chart of this utility model.

[0022] In the diagram: 1 Denitrification system, 2 Gas collection hood, 3 First exhaust fan, 4 Second exhaust fan, 5 Three-way valve, 6 First shut-off valve, 7 Second shut-off valve, 8 Third shut-off valve, 9 Fourth shut-off valve, 10 First ammonia detector, 11 Second ammonia detector, 12 Central control terminal, 13 Display terminal. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0025] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0026] like Figure 1 As shown, an ammonia leakage monitoring device for a denitrification system in a thermal power plant includes a gas collection hood 2, an exhaust fan, an ammonia detector, and a centralized control terminal 12; wherein:

[0027] The gas collection hood 2 is installed directly above the denitrification system 1, covering the equipment area of ​​the ammonia gas conveying and regulating pipeline of the denitrification system 1, especially the valves and other areas where ammonia gas leakage is likely to occur, in order to collect the leaked ammonia gas.

[0028] The inlet pipe of the exhaust fan is installed on the top of the air collection hood 2 to create negative pressure suction inside the air collection hood 2.

[0029] The ammonia detector is installed on the outlet pipe of the exhaust fan to detect the ammonia concentration; the gas flowing through the ammonia detector can be discharged into the atmosphere at a high point.

[0030] The centralized control terminal 12 is electrically connected to the ammonia detector to monitor and display the monitored ammonia concentration value.

[0031] In one embodiment, two sets of exhaust fans are provided, and an ammonia detector is installed on the outlet pipe of both sets of exhaust fans; when the exhaust fans or ammonia detectors need to be inspected or maintained, they can be switched to be put into use to ensure the normal operation of the system.

[0032] The exhaust fan can be a frequency converter or equipped with a timer module to be activated at certain intervals to ensure low energy consumption.

[0033] Preferably, the inlet pipes of the two exhaust fans are connected to the gas collection hood 2 through a three-way valve 5. By switching the three-way valve 5, the two exhaust fans can be in a "one-for-one" state, or the faulty exhaust fan can be switched off.

[0034] like Figure 1 In the example, the exhaust fan on the left is the first exhaust fan 3, the exhaust fan on the right is the second exhaust fan 4, the ammonia detector on the left is the first ammonia detector 10, and the ammonia detector on the right is the second ammonia detector 11; the position where the three-way valve 5 is connected to the first exhaust fan 3 is the first position, and the position where the three-way valve 5 is connected to the second exhaust fan 4 is the second position.

[0035] In another embodiment, the device includes a valve group for connecting the two sets of exhaust fans to either ammonia detector; by switching the valve group, the two sets of fans and the two sets of ammonia detectors can be used in any combination, thereby ensuring the continuity of the ammonia leak monitoring process and reducing the risk of monitoring interruption due to equipment failure.

[0036] Specifically, the valve group includes multiple shut-off valves, which are respectively installed on the outlet pipes of the two sets of exhaust fans and the inlet pipes of the two ammonia detectors. In the figure, the shut-off valves on the outlet pipes of the left and right sets of exhaust fans are the first shut-off valve 6 and the second shut-off valve 7, respectively, and the shut-off valves on the inlet pipes of the left and right ammonia detectors are the third shut-off valve 8 and the fourth shut-off valve 9, respectively.

[0037] Therefore, the device has four operating procedures, and the states of its valves are as follows:

[0038] (1) The first exhaust fan 3 is allowed, the first ammonia detector 10 is put into operation: the three-way valve 5 is in the first position, the first shut-off valve 6 and the third shut-off valve 8 are open, and the second shut-off valve 7 and the fourth shut-off valve 9 are closed;

[0039] (2) When the first exhaust fan 3 is enabled and the second ammonia detector 11 is put into operation: the three-way valve 5 is in the first position, the first shut-off valve 6 and the fourth shut-off valve 9 are open, and the second shut-off valve 7 and the third shut-off valve 8 are closed;

[0040] (3) When the second exhaust fan 4 is enabled, the first ammonia detector 10 is put into operation: the three-way valve 5 is in the second position, the second shut-off valve 7 and the third shut-off valve 8 are open, and the first shut-off valve 6 and the fourth shut-off valve 9 are closed;

[0041] (4) The second exhaust fan 4 is allowed, the second ammonia detector 11 is put into use: the three-way valve 5 is in the second position, the second shut-off valve 7 and the fourth shut-off valve 9 are open, and the first shut-off valve 6 and the third shut-off valve 8 are closed.

[0042] In one embodiment, the three-way valve 5 and the shut-off valve are manual valves or electric valves. The manual valves can realize the four operating states of the device, but require manual switching on site.

[0043] In another embodiment, the central control terminal 12 has a built-in control program that enables any ammonia detector to connect to any exhaust fan via the control of an electric valve.

[0044] Specifically, both the three-way valve 5 and the shut-off valve are solenoid valves. When the power is on or off, the three-way valve 5 is in the first position and the second position, respectively. When the power is on, the shut-off valve is open, and when the power is off, the shut-off valve is closed. Therefore, by controlling the power on and off, the opening and closing states of the three-way valve 5 and the shut-off valve can be remotely controlled.

[0045] The three-way valve 5 is also equipped with a signal that can provide feedback on its position status, and the shut-off valve is equipped with a signal that can provide feedback on its open or closed status; the two sets of exhaust fans are equipped with remote start and stop functions, and are also equipped with signals that can provide feedback on their running or stopped status.

[0046] Therefore, by electrically connecting the start / stop control of the two sets of exhaust fans, the opening / closing control of the three-way valve 5 and the shut-off valve to the control cabinet of the centralized control terminal 12, and electrically connecting the status signals of the three-way valve 5, the shut-off valve and the exhaust fans to the control cabinet, the remote switching control of the device can be realized.

[0047] In another embodiment, the centralized control terminal 12 is provided with a display terminal 13 for displaying the flowchart and operating status screen of the device.

[0048] Based on the operating status of the device, the four operating flowcharts and the permissible status of the exhaust fan and each valve can be displayed in real time on the display terminal 13, making it easier to view the operating status of the device more intuitively.

[0049] The start / stop control of the two sets of exhaust fans and the opening / closing control of the three-way valve 5 and the shut-off valve can also be set on the display terminal 13, so that the switching, activation or shutdown of the device can be realized on the display terminal 13.

[0050] Alternatively, a PLC module can be installed inside the control cabinet, and a control program can be set within the PLC module. When the exhaust fan, three-way valve 5, or shut-off valve malfunctions, the operating process will be automatically switched according to the program.

[0051] In one embodiment, the ammonia detector is electrically connected to an audible and visual alarm, which is installed on a platform near the ammonia supply pipeline of the denitrification system 1. When ammonia leaks and is detected to exceed the standard, the audible and visual alarm will sound an alarm to alert on-site inspection personnel or to inform them of the area where the leak occurred.

[0052] In one embodiment, the gas collection hood 2 is umbrella-shaped, and leaked ammonia gas can easily accumulate at the top inner part of the gas collection hood 2, making it easier for the exhaust fan to draw it in, thus enabling the ammonia gas leak to be detected immediately.

[0053] It should be noted that the equipment and pipelines of this device are installed on the platform of the denitrification system 1, and other platforms can also be welded to this platform for the installation of this device.

[0054] When in use, select one of the four operating processes to activate the device. The exhaust fan will draw the gas accumulated in the gas collection hood 2 and pass it through the ammonia detector for testing. The detected ammonia value will be displayed on the display terminal 13. When the detected ammonia value exceeds the standard, the audible and visual alarm will sound. If the equipment malfunctions, it can be manually switched on-site, remotely controlled, or automatically switched.

[0055] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An ammonia gas leakage monitoring device for a denitration system of a thermal power plant, characterized by, The application relates to a device for monitoring ammonia leakage in a denitration system. The device comprises: a gas collecting hood installed above the denitration system to collect leaked ammonia; an air extractor with an inlet pipe installed on the top of the gas collecting hood to form a negative pressure suction in the gas collecting hood; an ammonia detector installed on the outlet pipe of the air extractor to detect the ammonia concentration; a control terminal electrically connected with the ammonia detector to monitor and display the monitored ammonia concentration value. The air extractor is provided with two sets of air extractors, and the outlet pipes of the two sets of air extractors are both provided with ammonia detectors; the inlet pipes of the two sets of air extractors are connected with the gas collecting hood through a three-way valve.

2. The ammonia leakage monitoring device for a denitration system of a thermal power plant according to claim 1, characterized in that, The device further comprises a valve group for connecting the two sets of air extractors with any ammonia detector.

3. The ammonia leakage monitoring device for a denitration system of a thermal power plant according to claim 2, characterized in that, The valve group comprises a plurality of cut-off valves arranged on the outlet pipes of the two sets of air extractors and the inlet pipes of the two ammonia detectors.

4. The ammonia leakage monitoring device for a denitration system of a thermal power plant according to claim 3, characterized in that, The three-way valve and the cut-off valves are manual valves or electric valves.

5. The ammonia leakage monitoring device for a denitration system of a thermal power plant according to claim 1, characterized in that, The control terminal is provided with a display terminal for displaying a device flow chart and an operation state picture.

6. The ammonia leakage monitoring device for a denitration system of a thermal power plant according to claim 1, characterized in that, The ammonia detector is electrically connected with an audible and visual alarm installed on a platform near an ammonia supply pipe of the denitration system.

7. The ammonia leakage monitoring device for a denitration system of a thermal power plant according to claim 1, characterized in that, The gas collecting hood is in the shape of an umbrella cover.

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