Ash removal device and ash removal system of air preheater

Abstract

The utility model provides an ash removal device and an ash removal system of an air preheater. The ash removal device comprises a shock wave guide pipe, a pulse tank and a gas distribution ignition device, a first inlet, a second inlet and an outlet are formed in the gas distribution ignition device, the first inlet is used for receiving air, and the second inlet is used for receiving combustible gas; the outlet is connected with one end of the pulse tank; the shock wave conduit is connected with the other end of the pulse tank; and at least one nozzle is arranged on the shock wave conduit. According to the ash removal device, strong shock waves generated by deflagration reaction of air and combustible gas can be directionally sprayed out through the nozzle of the shock wave guide pipe, dust attached to the surface of an element falls off through vibration generated by the acting force of the shock waves, and therefore ash removal operation is achieved. In the whole ash removal process, operation is easy, the operation process is safe and reliable, and the ash removal effect and the ash removal efficiency are effectively improved.

Description

Technical Field

[0001] The utility model relates to, in particular to, a dust cleaning device and a dust cleaning system for an air preheater. Background Art

[0002] Ammonia leakage is unavoidable during the operation of the SCR denitrification device in the flue of a coal-fired unit. The escaped ammonia will react with sulfuric acid in the flue gas to form ammonium bisulfate. Ammonium bisulfate has strong adhesion and will quickly adhere to the surface of the heat transfer element, thereby adsorbing a large amount of ash, causing the rotary air preheater to become blocked, seriously affecting the normal operation of the air preheater and reducing the heat exchange efficiency. Ammonium bisulfate is also a strong corrosive. When the flue gas temperature drops to about 230°C, it will condense from gas to liquid, causing strong corrosion to the medium and low temperature sections of the rotary air preheater, damaging the internal structure of the rotary air preheater, and shortening the service life of the equipment. The blockage and corrosion of the rotary air preheater will also affect the overall operating stability of the generator set, resulting in a decrease in power generation efficiency and even causing safety accidents.

[0003] Traditional cleaning methods mainly include ultrasonic cleaning and steam cleaning. Steam cleaning uses steam for blowing to remove accumulated dust and particles, but the high temperature environment will increase the equipment failure rate and the operation is relatively complicated, requiring professional personnel to operate and monitor, which increases the operating cost to a certain extent. Sonic cleaning uses the vibration generated by sound waves to remove dust, but the cleaning effect is easily affected by many factors such as the frequency and energy of the sound waves and the nature of the accumulated dust, resulting in the cleaning effect being less than expected. At the same time, due to the complexity of the technology, it also requires higher investment costs. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the defects of high failure rate, complicated operation, poor cleaning effect and high investment cost of the cleaning equipment in the prior art, and to provide a cleaning device and a cleaning system for an air preheater.

[0005] The utility model solves the above technical problems through the following technical solutions:

[0006] As a first aspect of the present application, the present application provides a dust cleaning device.

[0007] The above-mentioned dust removal device includes a shock wave guide tube, a pulse tank and a gas distribution ignition device;

[0008] The gas distribution ignition device is provided with a first inlet, a second inlet and an outlet, the first inlet is used to receive air, and the second inlet is used to receive combustible gas;

[0009] The outlet is connected to one end of the pulse tank;

[0010] The shock wave guide tube is connected to the other end of the pulse tank;

[0011] The shock wave guide tube is provided with at least one nozzle.

[0012] Optionally, the dust cleaning device includes an air compression device and a combustible gas device;

[0013] The first inlet is connected to the air compression device via a first pipeline;

[0014] The second inlet is connected to the combustible gas device through a second pipeline.

[0015] Optionally, the dust cleaning device includes a central controller;

[0016] The gas distribution and ignition device is electrically connected to the central controller, and is used to receive a first control signal output by the central controller, and control the opening and closing of the first inlet and the second inlet according to the first control signal.

[0017] Optionally, the combustible gas device is electrically connected to the central controller, and the combustible gas device is used to receive a second control signal output by the central controller and control the output amount of the combustible gas in the combustible gas device according to the second control signal.

[0018] The shape of the nozzle is rhombus.

[0019] The gas distribution ignition device is provided with a pressure sensor for monitoring the shock wave pressure generated when the mixed gas in the pulse tank undergoes an explosion reaction;

[0020] and / or,

[0021] The gas distribution ignition device is provided with a temperature sensor for monitoring the temperature generated when the mixed gas in the pulse tank undergoes an explosion reaction.

[0022] The combustible gas device comprises a gas leakage alarm, and the gas leakage alarm is used to monitor whether the combustible gas leaks.

[0023] There is at least one shock wave guide tube, and all shock wave guide tubes are connected to the other end of the pulse tank.

[0024] As a second aspect of the present application, the present application provides a dust cleaning system for an air preheater, the dust cleaning system comprising an air preheater and a dust cleaning device as described in the first aspect above;

[0025] The shock wave guide tube is arranged inside the air preheater.

[0026] The air preheater is a rotary air preheater.

[0027] On the basis of conforming to the common sense in the art, the above optional conditions can be arbitrarily combined to obtain the preferred embodiments of the utility model.

[0028] The positive progressive effect of the utility model is that the combustible gas and air are mixed through the gas distribution ignition device, the mixed gas is introduced into the pulse tank to make it produce a deflagration reaction, the nozzle arranged on the shock wave guide tube will directionally spray the shock wave generated by the deflagration reaction, and the vibration generated by the shock wave force is used to make the dust attached to the surface of the component fall off, thereby realizing the cleaning operation. The operation is simple and the operation process is safe and reliable in the whole cleaning process, which effectively improves the cleaning effect and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of a dust cleaning device provided in Example 1 of the utility model.

[0030] Figure 2 This is a schematic structural diagram of another dust cleaning device provided in Example 1 of the utility model.

[0031] Figure 3 This is a schematic structural diagram of the dust cleaning system for the air preheater provided in Example 2 of the utility model. DETAILED DESCRIPTION

[0032] A preferred embodiment is given below, and the present invention is described more clearly and completely in conjunction with the accompanying drawings.

[0033] Example 1

[0034] See also Figure 1 The present embodiment provides a dust cleaning device, comprising a gas distribution ignition device 1, a pulse tank 2 and a shock wave guide tube 3; the gas distribution ignition device is provided with a first inlet, a second inlet and an outlet, the first inlet is used to receive air, and the second inlet is used to receive combustible gas; the outlet is connected to one end of the pulse tank; the shock wave guide tube is connected to the other end of the pulse tank; and at least one nozzle is provided on the shock wave guide tube.

[0035] When using the cleaning device in this embodiment, the combustible gas and air are mixed through the gas distribution ignition device, and the mixed gas is introduced into the pulse tank to cause a deflagration reaction. The nozzle arranged on the shock wave guide tube will directionally eject the shock wave generated by the deflagration reaction, and the vibration generated by the shock wave force is used to cause the dust attached to the surface of the component to fall off, thereby realizing the cleaning operation. The operation is simple and the operation process is safe and reliable throughout the cleaning process, which effectively improves the cleaning effect and efficiency.

[0036] In an optional embodiment, see Figure 2The dust cleaning device further comprises a central controller 4, a combustible gas device 5 and an air compression device 6. The first inlet is connected to the air compression device through a first pipeline; the second inlet is connected to the combustible gas device through a second pipeline.

[0037] Specifically, the first pipeline can be an air pipeline for conducting air provided by an air compression device; the second pipeline can be a fuel gas pipeline for conducting fuel gas provided by a fuel gas device. In a specific implementation, the fuel gas device can be an acetylene gas device for providing acetylene gas. Before starting the dust cleaning device, check whether the air pipeline and the acetylene pipeline are tight. If the pipelines are tight, open the acetylene gas cylinder. The normal acetylene gas pressure is controlled at 0.08-0.15MPa, and the compressed air pressure is controlled at 0.3-0.6MPa. In order to maintain the stability of the acetylene gas pressure, more than two bottles of acetylene gas are usually required. In other embodiments, the fuel gas device can also be a device that provides other fuel gases.

[0038] In an optional embodiment, the cleaning device includes a central controller, and the gas distribution ignition device is electrically connected to the central controller. The gas distribution ignition device is used to receive a first control signal output by the central controller and control the opening and closing of a first inlet and a second inlet on the gas distribution ignition device according to the first control signal.

[0039] In a specific example, the gas distribution ignition device and the central controller can be connected by a cable. When the first control signal sent by the central controller is at a high level, the gas distribution ignition device controls the closing of the first inlet and the second inlet, and the air and the combustible gas stop entering the gas distribution ignition device; when the first control signal sent by the central controller is at a low level, the gas distribution ignition device controls the opening of the first inlet and the second inlet, and the air and the combustible gas enter the gas distribution ignition device and mix, and the mixed gas enters the pulse tank through the conduit, wherein the conduit is located at the bottom of the pulse tank, and the mixed gas gradually fills the pulse tank from top to bottom under the action of pressure. When the mixed gas volume in the pulse tank reaches a preset threshold, an explosion reaction occurs. For example, when the mixed gas volume in the pulse tank reaches 94%, the gas distribution ignition device generates an electric spark to cause the mixed gas to undergo an explosion reaction.

[0040] The gas distribution ignition device controls the opening of the first inlet and the second inlet to allow air and combustible gas to enter the pulse tank, thereby controlling the occurrence of the deflagration reaction of the ash cleaning device; after the deflagration reaction occurs, the gas volume in the pulse tank will drop rapidly. At this time, the gas distribution ignition device controls the opening of the first inlet and the second inlet to allow air and combustible gas to enter the pulse tank again. When the gas volume in the pulse tank reaches the preset threshold, the deflagration reaction will occur again. Therefore, when air and combustible gas are continuously input, the ash cleaning device will cyclically undergo a deflagration reaction. Therefore, the central controller can control the frequency of the deflagration reaction of the ash cleaning device by controlling the opening and closing of the first inlet and the second inlet on the gas distribution ignition device.

[0041] In an optional embodiment, the combustible gas device is electrically connected to the central controller, and the combustible gas device is used to receive a second control signal output by the central controller and control the output amount of the combustible gas in the combustible gas device according to the second control signal.

[0042] In a specific example, the combustible gas device can be connected to the central controller via a cable. When the combustible gas device receives the second control signal sent by the central controller, it controls the amount of combustible gas output according to the level of the second control signal. When the second control signal is at a high level, it indicates that the combustible gas device provides the maximum combustible gas output; when the second control signal is at a low level, it indicates that the combustible gas device provides the minimum combustible gas output. The higher the level of the second control signal, the greater the combustible gas output provided by the combustible gas. The greater the combustible gas output, the higher the proportion of combustible gas in the mixed gas of the gas distribution ignition device, the higher the intensity of the deflagration reaction, and the better the cleaning effect, but the combustible gas consumption at this time will be greater.

[0043] Specifically, the frequency and level of the deflagration reaction in the cleaning device can be set according to the ash accumulation conditions. If the ash accumulation is serious, a higher deflagration level will be set. At this time, the central controller will control the combustible gas device to output more combustible gas, increase the proportion of combustible gas in the mixed gas, and enhance the intensity of the deflagration reaction, so as to achieve a better cleaning effect.

[0044] In another optional implementation, the central controller includes a programmable logic controller (PLC), a color touch screen, supporting application software, a communication control module, a relay, an air switch and other components, all of which are integrated in a control cabinet, which can realize real-time display and real-time control of the working status of the entire dust cleaning device. After power is turned on, the PLC indicator light is on. Do not disconnect the power switch of the control cabinet at will during normal operation to avoid affecting the working status of the entire dust cleaning device.

[0045] The central controller can control the cleaning device to realize two working modes: fully automatic control and manual control. In the fully automatic control mode, the cleaning device will automatically control the cycle and level of the deflagration reaction according to the parameters set by the central controller. After the preset time is reached, the cleaning device will automatically start and control the output of the combustible gas according to the preset level of deflagration, thereby controlling the level of deflagration; while in the manual control mode, the start and stop of the cleaning device need to be manually controlled. When the cleaning device needs to be turned on, press the "Start" button, the operation indicator light will light up, and the work will start after setting the parameters. After the work is completed, it will return to the initial state of operation, and the operation indicator light will go out; if you encounter special circumstances during the operation, you can use the "Stop" button to stop the cleaning device and the operation indicator light will go out.

[0046] In an optional embodiment, the nozzle shape on the shock wave guide tube can be diamond-shaped. The shock wave generated by the explosion of the mixed gas in the pulse tank will be directed to the surface of the dust accumulation component through the diamond-shaped nozzle on the shock wave guide tube at a speed of 1000-1500m / s. The vibration generated by the shock wave will shake off the dust attached to the surface of the component, thereby achieving a dust cleaning effect. The more diamond-shaped nozzles distributed on the shock wave guide tube, the larger the area that can be covered by the ejected shock wave, and therefore, the better the dust cleaning effect produced by the dust cleaning device will be.

[0047] In an optional embodiment, a pressure sensor is provided in the gas distribution ignition device for monitoring the shock wave pressure generated when the mixed gas in the pulse tank undergoes a deflagration reaction.

[0048] In an optional embodiment, a temperature sensor is also provided in the gas distribution ignition device for monitoring the temperature generated when the mixed gas in the pulse tank undergoes a deflagration reaction.

[0049] If the shock wave pressure and temperature generated after the deflagration reaction do not reach the preset threshold, it means that the mixed gas in the pulse tank has not fully undergone a deflagration reaction, and combustible gas that has not fully undergone a deflagration reaction may remain in the pulse tank and the shock wave duct. At this time, the cleaning device will perform a pressurization operation to discharge the remaining combustible gas to ensure the safety of the cleaning device.

[0050] In an optional embodiment, the combustible gas device includes a gas leak meter for monitoring whether the combustible gas leaks.

[0051] In a specific example, the combustible gas device can be an acetylene device for providing acetylene gas. The device includes an acetylene gas cylinder, a gas leak meter, a remote pressure transmitter and an outlet main valve. All components are placed in a cabinet. The cabinet adopts an open structure, with a sheet metal frame and a welded steel mesh as the external panel, which is convenient for direct observation of the internal conditions. At the same time, it can maintain air circulation and avoid the large accumulation of acetylene gas. The threaded interfaces on all connecting pipes in the cabinet are sealed with anaerobic sealant to ensure that acetylene gas will not leak through the threaded connections. If acetylene gas leaks, the gas leak meter will send an alarm signal. After the central controller obtains the alarm signal, it will output a closed gas signal. At this time, the combustible gas device closes the outlet main valve to prevent the acetylene gas from continuing to leak.

[0052] The remaining gas content in the acetylene cylinder can be monitored by an on-site remote pressure transmitter. If the pressure of the acetylene cylinder is insufficient, a low pressure alarm signal will appear, reminding you that you need to replace a new acetylene cylinder. After replacing the acetylene cylinder, when the acetylene pressure value is greater than 0.08MPa, the low pressure alarm will be automatically released, and the cleaning device can operate normally. After the cleaning device is finished, close the main outlet valve of the acetylene cylinder.

[0053] In an optional embodiment, there is at least one shock wave guide tube, and all shock wave guide tubes are connected to the other end of the pulse tank. In a specific example, there are two shock wave guide tubes in the cleaning device, one end of the pulse tank is connected to the gas distribution ignition device, and the two shock wave guide tubes are connected to the other end of the pulse tank. The two shock wave guide tubes can guide the shock waves generated by the deflagration reaction into different devices, so that one set of cleaning device can perform cleaning treatment on two sets of equipment, which improves the use efficiency of the cleaning device and reduces the cost.

[0054] When using the cleaning device in this embodiment, the combustible gas and air are mixed through the gas distribution ignition device, and the mixed gas is introduced into the pulse tank to cause a deflagration reaction. The nozzle arranged on the shock wave guide tube will directionally eject the shock wave generated by the deflagration reaction, and the vibration generated by the shock wave force is used to cause the dust attached to the surface of the component to fall off, thereby realizing the cleaning operation. The operation is simple and the operation process is safe and reliable throughout the cleaning process, which effectively improves the cleaning effect and efficiency.

[0055] Example 2

[0056] This embodiment provides a dust cleaning system for an air preheater. Figure 3 , including an air preheater 7 and a dust cleaning device as described in Example 1; the shock waveguide is arranged inside the air preheater.

[0057] In a specific implementation, the air preheater may be a rotary air preheater.

[0058] In an optional embodiment, the shock wave guide tube is located below the cold end element in the air preheater. The shock wave guide tube transmits the shock wave generated by the explosion reaction of the mixed gas to the inside of the rotary air preheater. The generated vibration will remove the dust attached to the cold end element inside the rotary air preheater.

[0059] Using the cleaning system of the air preheater in this embodiment, the combustible gas and air are mixed through a gas distribution ignition device, and the mixed gas is introduced into a pulse tank to cause a deflagration reaction. The nozzle arranged on the shock wave guide tube will spray out the shock wave generated by the deflagration reaction, and the vibration generated by the shock wave force will cause the dust attached to the surface of the component to fall off, thereby realizing the cleaning operation. The operation is simple and the operation process is safe and reliable throughout the cleaning process, which effectively improves the cleaning effect and efficiency.

Claims

1. A dust cleaning device, characterized in that: The dust removal device includes a shock wave guide tube, a pulse tank and a gas distribution ignition device; The gas distribution ignition device is provided with a first inlet, a second inlet and an outlet, the first inlet is used to receive air, and the second inlet is used to receive combustible gas; The outlet is connected to one end of the pulse tank; The shock wave guide tube is connected to the other end of the pulse tank; The shock wave guide tube is provided with at least one nozzle.

2. The dust cleaning device according to claim 1, characterized in that: The dust cleaning device includes an air compression device and a combustible gas device; The first inlet is connected to the air compression device via a first pipeline; The second inlet is connected to the combustible gas device through a second pipeline.

3. The dust cleaning device according to claim 2, characterized in that: The dust cleaning device includes a central controller; The gas distribution and ignition device is electrically connected to the central controller, and is used to receive a first control signal output by the central controller, and control the opening and closing of the first inlet and the second inlet according to the first control signal.

4. The dust cleaning device according to claim 3, characterized in that: The combustible gas device is electrically connected to the central controller, and is used to receive a second control signal output by the central controller and control the output amount of the combustible gas in the combustible gas device according to the second control signal.

5. The dust cleaning device according to claim 1, characterized in that: The shape of the nozzle is rhombus.

6. The dust cleaning device according to claim 1, characterized in that: The gas distribution ignition device is provided with a pressure sensor for monitoring the shock wave pressure generated when the mixed gas in the pulse tank undergoes an explosion reaction; and / or, The gas distribution ignition device is provided with a temperature sensor for monitoring the temperature generated when the mixed gas in the pulse tank undergoes an explosion reaction.

7. The dust cleaning device according to claim 2, characterized in that: The combustible gas device comprises a gas leakage alarm, and the gas leakage alarm is used to monitor whether the combustible gas leaks.

8. The dust cleaning device according to claim 1, characterized in that: There is at least one shock wave guide tube, and all shock wave guide tubes are connected to the other end of the pulse tank.

9. A dust cleaning system for an air preheater, characterized in that: The dust cleaning system comprises an air preheater and a dust cleaning device as described in any one of claims 1 to 8; The shock wave guide tube is arranged inside the air preheater.

10. The dust cleaning system according to claim 9, characterized in that: The air preheater is a rotary air preheater.

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