Rotary arm type online ash removal device for air preheater

Abstract

The utility model relates to a tumbler type on-line air preheater deashing device which comprises a sealing box, a large tumbler, a small tumbler, an air injection mechanism and a cold air cooling system, the sealing box is fixedly connected with a main support in a boiler, an installation support is installed on the inner side of the back of the sealing box, the large tumbler is installed on the inner side of the back of the sealing box through the installation support, and the small tumbler is installed on the air injection mechanism. The small rotating arm is installed below the tail end of the large rotating arm and connected with the large rotating arm through a bearing, the air injection mechanism is installed at the tail end of the small rotating arm, the large rotating arm comprises a hollow outer stand column, a header and a hollow inner stand column, a transmission mechanism I is installed in the outer stand column, a transmission mechanism II is installed in the inner stand column, and a motor I and a motor II are installed in the header. The motor I drives the outer stand column to swing, and the motor II drives the small rotating arm to swing. By the adoption of the technical scheme, the heat exchange tube of the air preheater in the boiler flue can be cleaned and dredged on line under the condition that the boiler is not shut down, operation is easy, and efficiency is high.

Description

Technical Field

[0001] The utility model relates to the field of boiler flue dredging equipment, in particular to a swing-arm type on-line air preheater ash cleaning device. Background Technique

[0002] After the flue gas of the factory boiler is discharged from the furnace, it still contains a large amount of available heat. In order to save energy and protect the environment, it is necessary to recover as much heat as possible before discharging it into the chimney. Installing an air preheater on the flue is an essential step. At present, most boilers use tubular air preheaters, and the heat exchange tubes generally adopt a staggered arrangement. The air preheater is installed in the boiler flue through the main support. Since the flue gas contains a large amount of dust, which is mainly formed by molecular attraction and electrostatic action, and the diameter and unit mass of the ash particles are very small. When the ash particles contact the pipe wall, when the attraction between its molecules and the pipe wall is greater than the gravity of the ash particles, the dust is very easy to deposit on the heat exchange pipes, resulting in loose ash accumulation on the inner wall of the heat exchange tubes of the air preheater. At the same time, there are also multiple groups of other chemical substances in the flue gas. In the high-temperature environment of the flue gas, complex chemical reactions will also occur. The chemical substances generated will combine with the loose ash deposited on the inner wall of the pipe to form a harder polymer, which will ultimately seriously affect the heat transfer effect of the air preheater, cause low-temperature dew point corrosion, and at the same time, the viscosity of the ash will increase, the ash layer will continue to thicken, further reducing the air preheating temperature, expanding the dew point temperature range, and at the same time expanding the area of sticky ash, accelerating the speed of ash accumulation and scaling; forming a vicious cycle, and in the long run, it is very easy to cause the air preheater to fail. This requires regular cleaning and maintenance of the heat exchange tubes of the air preheater. However, due to the huge number of heat exchange tubes of the air preheater, it takes a lot of manpower and time to clean the pipes, and the cleaning difficulty is extremely high or even impossible to clean and dredge. If a device with a simple structure that can quickly clean and dredge the ash accumulation in the heat exchange pipes without stopping the boiler operation can be provided, and the loose ash can be removed regularly and in time during the boiler operation, preventing the formation of hard polymers, improving the heat release coefficient on the flue gas side, increasing the wall temperature, preventing ash accumulation, reducing the thermal resistance, slowing down corrosion, it will be able to save a large amount of maintenance time and cost, extend the service life of the air preheater, and extend the boiler operation cycle. Summary of the Invention

[0003] The purpose of the utility model is to provide a boiler flue dredging device that can quickly clean and dredge the heat exchange tubes of the air preheater in the boiler flue without stopping the boiler operation, aiming to solve the problem of extremely difficult ash cleaning of the heat exchange tubes of the air preheater installed in the boiler flue.

[0004] The technical solution adopted by the utility model is as follows: A rotary arm type on-line air preheater ash cleaning device, which includes a sealing box, a large rotary arm, a small rotary arm, a jetting mechanism and a cold air cooling system. The sealing box is fixedly connected to the main support in the boiler flue. The box body of the sealing box is located outside the air preheater. The sealing box is in a cuboid shape. A sealing inner door is arranged at the front of the sealing box, and a sealing outer door is arranged on the back of the sealing box. An installation bracket is installed on the inner side of the back of the sealing box. The large rotary arm is installed on the inner side of the back of the sealing box through the installation bracket. The small rotary arm is installed below the end of the large rotary arm. The small rotary arm is connected to the large rotary arm through a bearing, so that the small rotary arm can swing freely below the large rotary arm. The jetting mechanism is installed at the end of the small rotary arm. The large rotary arm includes a hollow outer column, a header tank and a hollow inner column. The outer column, the header tank and the inner column are connected to each other. Rotary bearings are respectively installed at the top and bottom of the outer column. A transmission mechanism I is installed inside the outer column, and a transmission mechanism II is installed inside the inner column. A motor I and a motor II are installed inside the header tank. The output end of the motor I is connected to the transmission mechanism I through a chain to drive the outer column to rotate, and thus the large rotary arm to swing. The output end of the motor II is connected to the transmission mechanism II through a chain to drive the small rotary arm to swing. The jetting mechanism includes an air compressor, a compressed air pipeline, a jetting valve, a nozzle lifting mechanism and a nozzle. A fixed protection pipe is arranged above the outer column. A rotary bearing is arranged inside the fixed protection pipe. The compressed air pipeline is externally connected to the air compressor. The compressed air pipeline is installed inside the fixed protection pipe through the rotary bearing and extends downward through the rotary bearing at the top of the outer column into the interior of the outer column, and then extends out from the side of the outer column, passes through the interior of the header tank and is connected to the interior of the inner column, and finally extends to the end of the small rotary arm and is connected to the jetting valve. The jetting valve and the nozzle lifting mechanism are controlled by an automatic control system. The cold air cooling system cools the outer column, the header tank, the inner column and the jetting mechanism.

[0005] A further technical solution of the present utility model is that the cold air cooling system includes a first cooling system and a second cooling system. The first cooling system includes a first blower and an exhaust fan. A fixed hollow shaft is provided at the bottom of the outer column, an air extraction port is provided on the lower side of the outer column, an air vent Ⅰ is opened at the connection part between the outer column and the header tank, an air vent Ⅱ is opened at the connection part between the inner column and the header tank, the lower end of the fixed hollow shaft is a first air inlet, and an air supply pipeline is further laid inside the bottom of the header tank. One end of the air supply pipeline communicates with the lower part of the inner column, and the other end communicates with the lower part of the outer column. The cold air blown by the first blower enters the fixed hollow shaft from the first air inlet, then enters the outer column, then enters the header tank from the air vent Ⅰ, then enters the inner column from the air vent Ⅱ, and finally enters the air supply pipeline from the lower side of the inner column and is extracted by the exhaust fan from the air extraction port; The second cooling system includes a second blower. An inner column partition is provided at the upper middle position inside the inner column, dividing the inside of the inner column into an upper cavity and a lower cavity. A main pipeline is installed in the lower cavity of the inner column. The front end of the main pipeline is connected to the inner column partition, and the end of the main pipeline extends to the end of the small swing arm and is connected to the jet mechanism. An opening is provided on the upper side of the main pipeline. A butt joint is provided at the place where the compressed air pipeline enters the header tank. A compressed air guide pipe is installed between the butt joint and the opening. An inner sleeve is further provided in the main pipeline. The upper end of the inner sleeve communicates with the upper cavity of the inner column and extends along the main pipeline to the side of the jet valve. A cooling pipeline is further provided at the middle and lower part of the outer column. The cooling pipeline is externally connected to the second blower. The cooling pipeline passes through the inside of the outer column and the inside of the header tank and then docks with the upper cavity of the inner column. The cooling pipeline is provided with an interface Ⅰ when entering the header tank body and an interface Ⅱ on the upper cavity of the inner column. A guide pipe is installed between the interface Ⅰ and the interface Ⅱ. The cold air blown by the second blower enters the upper cavity of the inner column after passing through the cooling pipeline, then enters the inner sleeve, is guided by the inner sleeve to the vicinity of the jet valve for cooling the jet valve, then turns back to cool the space between the small swing arm and the inner sleeve, and finally returns to the air supply pipeline inside the header tank and is extracted by the exhaust fan. Cooling is carried out in two ways to cool multiple parts and components. At the same time, the first way can cool the header tank and the gas in the cooling pipeline of the second way at the same time, and the cooling effects are superimposed to ensure the high efficiency of cooling.

[0006] A further technical solution of the present utility model is that: the mounting bracket includes an upper bracket and a lower bracket. Two rotary bearings are arranged inside the upper middle part of the outer column. An upper hollow shaft is installed on the rotary bearings. The upper hollow shaft passes through the upper end of the outer column and is fixedly connected to the upper bracket. The fixed hollow shaft is installed inside the lower middle part of the outer column through two rotary bearings. The lower end of the fixed hollow shaft passes through the lower end of the outer column and is fixedly connected to the lower bracket, so that the outer column can rotate between the upper bracket and the lower bracket, and the header box swings following the rotation of the outer column. When the outer column rotates, it rotates around the upper hollow shaft and the fixed hollow shaft, which is convenient for the installation and fixation of the outer column and improves the stability of the outer column.

[0007] A further technical solution of the present utility model is that: the outer surface of the swing arm type on-line air preheater soot cleaning device is coated with a heat insulation material to minimize the heat transfer of high-temperature flue gas to its outer surface.

[0008] The beneficial effect of the present utility model is that: due to the adoption of the above technical solution, the swing arm type on-line air preheater soot cleaning device of the present utility model can clean and dredge the heat exchange tubes of the air preheater in the boiler flue online without shutting down the boiler, with simple operation and high efficiency. Brief Description of the Drawings

[0009] Figure 1 is the overall structural schematic diagram of the swing arm type on-line air preheater soot cleaning device of the present utility model;

[0010] Figure 2 is the top view structural schematic diagram of the swing arm type on-line air preheater soot cleaning device of the present utility model when it is installed on the boiler flue and working;

[0011] Figure 3 is the top view structural schematic diagram of the swing arm type on-line air preheater soot cleaning device of the present utility model when it is installed on the boiler flue and in the standby state;

[0012] Figure 4 is the internal structural schematic diagram of the swing arm type on-line air preheater soot cleaning device;

[0013] Figure 5 is the side view structural schematic diagram of the sealing box;

[0014] Figure 6 is the structural schematic diagram of the air jetting mechanism. Detailed Description of the Embodiment

[0015] The following further describes the present utility model in conjunction with the drawings and specific embodiments.

[0016] Embodiment:

[0017] As Figures 1 to 6An ash cleaning device for a swing - type on - line air preheater shown in the figure, comprising a sealed box 2, a large swing arm, a small swing arm 7, a jetting mechanism 8 and a cold air cooling system. The sealed box is fixedly connected to the main support 10 in the boiler flue. The sealed box body is located outside the air preheater. The sealed box is in a cuboid shape. A sealed inner door 22 is arranged at the front of the sealed box, and the sealed inner door can be opened or closed by pushing or pulling. A sealed outer door 21 is arranged on the back of the sealed box, and an installation bracket 1 is installed on the inner side of the back of the sealed box. The large swing arm is installed on the inner side of the back of the sealed box through the installation bracket 1. The small swing arm 7 is installed below the end of the large swing arm. The small swing arm is connected to the large swing arm through a bearing, enabling the small swing arm to swing freely below the large swing arm. The jetting mechanism 8 is installed at the end of the small swing arm. The large swing arm includes a hollow outer column 4, a header 5 and a hollow inner column 6. The outer column, the header and the inner column are connected to each other. Rotary bearings are respectively installed at the top and bottom of the outer column. A transmission mechanism I 45 is installed inside the outer column, and a transmission mechanism II 64 is installed inside the inner column. A motor I 53 and a motor II 52 are installed inside the header. The output end of the motor I is connected to the transmission mechanism I through a chain to drive the outer column 4 to rotate, thereby making the large swing arm swing. The output end of the motor II is connected to the transmission mechanism II through a chain to drive the small swing arm 7 to swing. The jetting mechanism 8 includes an air compressor, a compressed air pipeline 31, a jetting valve 81, a nozzle lifting mechanism 82 and a nozzle 83. A fixed protection pipe 3 is arranged above the outer column. A rotary bearing is arranged inside the fixed protection pipe. The compressed air pipeline 31 is externally connected to the air compressor. The compressed air pipeline 31 is installed inside the fixed protection pipe through the rotary bearing and extends downward through the rotary bearing at the top of the outer column 4 into the interior of the outer column 4, then extends out from the side of the outer column and passes through the interior of the header 5 to be connected into the inner column 6, and finally extends to the end of the small swing arm to be connected to the jetting valve. The jetting valve and the nozzle lifting mechanism are controlled by an automatic control system. The cold air cooling system cools the outer column, the header, the inner column and the jetting mechanism.

[0018] Further, the cold air cooling system includes a first cooling system and a second cooling system. The first cooling system includes a first blower and an exhaust fan. A fixed hollow shaft 41 is provided at the bottom of the outer column. An inner partition 44 of the outer column is installed inside the outer column. The fixed hollow shaft extends from the bottom of the outer column into the outer column and extends to the inner partition of the outer column and is connected to the inner partition of the outer column. The inner cavity of the fixed hollow shaft is communicated with the interior of the outer column above the outer column partition. An air extraction port 42 is provided on the lower side of the lower part of the outer column. An air vent Ⅰ100 is opened at the connection part between the outer column and the header tank, and an air vent Ⅱ110 is opened at the connection part between the inner column and the header tank. The lower end of the fixed hollow shaft is the first air inlet. A gas supply pipe 51 is also laid inside the bottom of the header tank. One end of the gas supply pipe 51 is communicated with the lower part of the inner column, and the other end is communicated with the lower part of the outer column. The cold air blown by the first blower enters the fixed hollow shaft 41 from the first air inlet and then enters the outer column 4, then enters the header tank 5 from the air vent Ⅰ100, then enters the inner column from the air vent Ⅱ110, and finally enters the gas supply pipe 51 from the lower side of the lower part of the inner column 6 and is extracted by the exhaust fan from the air extraction port 42. The second cooling system includes a second blower. An inner column partition 62 is provided at the upper middle position inside the inner column, dividing the interior of the inner column into an upper cavity and a lower cavity. A main pipe 63 is installed inside the lower cavity of the inner column. The front end of the main pipe is connected to the inner column partition 62, and the end of the main pipe extends to the end of the small swing arm 7 and is connected to the jet mechanism 8. An opening 310 is provided on the upper side of the main pipe. For the convenience of installation, a docking port 300 is provided at the place where the compressed air pipe 31 enters the header tank 5. A compressed air guide pipe is installed between the docking port 300 and the opening 310. An inner sleeve 61 is also provided inside the main pipe. The upper end of the inner sleeve is communicated with the upper cavity of the inner column. The inner sleeve extends along the main pipe to the side of the jet valve 81 (at the main pipe near the jet valve, the inner sleeve passes through the upper part of the main pipe, and the opening at the end of the inner sleeve faces the jet valve so that the gas ejected from the inner sleeve during operation cools the jet valve). A cooling pipe 43 is also provided at the middle and lower part of the outer column. The cooling pipe is externally connected to the second blower. The cooling pipe 43 passes through the interior of the outer column and the interior of the header tank and is docked with the upper cavity of the inner column. Here, for the convenience of installation, an interface Ⅰ200 is provided at the place where the cooling pipe enters the header tank 5, and an interface Ⅱ210 is provided on the upper cavity of the inner column. A guide pipe is installed between the interface Ⅰ and the interface Ⅱ. The cold air blown by the second blower enters the upper cavity of the inner column after passing through the cooling pipe, then enters the inner sleeve, is guided by the inner sleeve to the vicinity of the jet valve to cool the jet valve, then turns back to cool the space between the small swing arm and the inner sleeve, and finally returns to the gas supply pipe inside the header tank and is extracted by the exhaust fan.When the boiler is operating normally, the flue gas temperature reaching above the lower air preheater is 150 - 200 °C. To enable the soot cleaning device to work inside, it is necessary to insulate and dust-proof the device, and at the same time, air-cool the inside of the soot cleaning device. This device uses two air-cooling paths to cool its inside, enabling the device to have a good cooling function.

[0019] Further, the installation bracket is a handle-type bracket, including an upper bracket and a lower bracket. Two rotary bearings are arranged inside the upper-middle part of the outer column. An upper hollow shaft 46 is installed on the rotary bearings, and the upper hollow shaft 46 passes through the upper end of the outer column 4 and is fixedly connected to the upper bracket; a fixed hollow shaft 41 is installed inside the lower-middle part of the outer column 4 through two rotary bearings, and the lower end of the fixed hollow shaft 41 passes through the lower end of the outer column 4 and is fixedly connected to the lower bracket, enabling the outer column to rotate between the upper bracket and the lower bracket around the upper hollow shaft and the fixed hollow shaft, and the header follows the rotation of the outer column and swings. When the outer column rotates, it rotates around the upper hollow shaft and the fixed hollow shaft, facilitating the installation and fixation of the outer column and improving the stability of the outer column.

[0020] Further, the outer surface of the swing-arm type on-line air preheater soot cleaning device is coated with heat-insulating material to minimize the heat transfer of high-temperature flue gas to its outer surface.

[0021] When the device is working, it is controlled by an automatic control system (the automatic control system is an existing technology and will not be elaborated here). The inner sealing door 22 of the sealing box 2 is opened, and the large swing arm and the small swing arm 7 enter directly above the upper plate 9 of the air preheater. By controlling the rotation of the large swing arm and the small swing arm by the automatic control system, the position of each tube hole of the heat exchange tube can be accurately found. Then, through the automatic control system, the jet valve 81 is opened and the nozzle lifting mechanism 82 in the jetting mechanism 8 works, so that the nozzle 83 is inserted into the heat exchange tube of the air preheater to a certain depth to clean and dredge the preheating tube. After the blowing and cleaning and dredging of each preheating tube are completed, the nozzle 83 rises, and the automatic rotation of the large swing arm and the small swing arm finds the nozzle of the next preheating tube that needs to be blown and cleaned and dredged. Then, again through the automatic control system, the jet valve is opened and the nozzle 83 in the jetting mechanism 8 is inserted into the heat exchange tube to a certain depth to clean and dredge the preheating tube.

[0022] After all the preheating tubes have been blown and cleaned and dredged, the automatic control system rotates the header 5, the inner column 6, the small swing arm 7, the jetting mechanism 8, etc. into the sealing box 2, and then the inner sealing door 22 is closed. If it is necessary to inspect or repair the soot cleaning device, the outer sealing door 21 can be opened for relevant work.

[0023] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A rotary arm type online air preheater dust cleaning device, characterized in that: It includes a sealed box, a large rotating arm, a small rotating arm, an injection mechanism and a cold air cooling system. The sealed box is fixedly connected to the main bracket in the boiler flue. The sealed box body is located outside the air preheater. The sealed box is in the shape of a rectangular parallelepiped. A sealed inner door is arranged at the front of the sealed box, a sealed outer door is arranged on the back of the sealed box, and a mounting bracket is installed on the inner side of the back of the sealed box. The large rotating arm is installed on the inner side of the back of the sealed box through the mounting bracket. The small rotating arm is installed below the end of the large rotating arm. The small rotating arm is connected to the large rotating arm through a bearing so that the small rotating arm can swing freely below the large rotating arm. The injection mechanism is installed at the end of the small rotating arm. The large rotating arm includes a hollow outer column, a header and a hollow inner column. The outer column, the header and the inner column are connected to each other. Rotary bearings are respectively installed on the top and bottom of the outer column. Transmission mechanism I is installed in the outer column, and transmission mechanism II is installed in the inner column. Motor I and motor II are installed in the header, the output end of motor I is connected to transmission mechanism I through a chain to drive the outer column to rotate and then swing the large swing arm, the output end of motor II is connected to transmission mechanism II through a chain to drive the small swing arm to swing, the jet mechanism includes an air compressor, a compressed air pipeline, a jet valve, a nozzle lifting mechanism and a nozzle, a fixed protective pipe is arranged above the outer column, the compressed air pipeline is externally connected to the air compressor, the compressed air pipeline is installed in the fixed protective pipe and extends downward through the rotating bearing at the top of the outer column to enter the interior of the outer column, then extends from the side of the outer column through the inside of the header to connect to the inner column, and finally extends to the end of the small swing arm to be connected to the jet valve, the jet valve and the nozzle lifting mechanism are controlled by an automatic control system; the cold air cooling system cools the outer column, the header, the inner column and the jet mechanism.

2. The rotary arm type online air preheater dust cleaning device according to claim 1 is characterized in that: The cold air cooling system includes a first cooling system and a second cooling system, the first cooling system includes a first blower and an exhaust fan, a fixed hollow shaft is provided at the bottom of the outer column, an exhaust port is provided on the side of the lower part of the outer column, an air vent I is provided at the position where the outer column and the header are connected to each other, an air vent II is provided at the position where the inner column and the header are connected to each other, the lower end of the fixed hollow shaft is a first air inlet, an air supply pipe is also laid in the bottom of the header, one end of the air supply pipe is connected to the lower part of the inner column, and the other end is connected to the outer The lower part of the column is connected, the cold air blown in by the first blower enters the fixed hollow shaft from the first air inlet and then enters the outer column, then enters the header from the vent I, and then enters the inner column from the vent II, and finally enters the air supply duct from the side of the lower part of the inner column and is extracted from the exhaust port by the exhaust fan; the second cooling system includes a second blower, an inner column partition is arranged at the middle and upper part of the inner column, the inner column is divided into an upper cavity and a lower cavity, the lower cavity of the inner column is installed with a main pipeline, the main pipeline The front end of the main pipeline is connected to the inner column partition, the end of the main pipeline extends to the end of the small rotating arm and is connected to the jet mechanism, an opening is arranged on the upper side of the main pipeline, a docking port is arranged at the compressed air pipeline entering the header, a compressed air guide pipe is installed between the docking port and the opening, an inner sleeve is also arranged in the main pipeline, the upper end of the inner sleeve is communicated with the upper cavity of the inner column, the inner sleeve extends along the main pipeline to the jet valve, a cooling pipeline is also arranged on the middle and lower part of the outer column, the cooling pipeline is externally connected to the second blower, and the cooling pipe The cooling duct passes through the inside of the outer column and the inside of the header box and docks with the upper cavity of the inner column. An interface I is set at the exit of the cooling duct entering the header box, and an interface II is set on the upper cavity of the inner column. An air guide pipe is installed between interface I and interface II. The cold air blown in by the second blower enters the upper cavity of the inner column after passing through the cooling duct, and then enters the inner sleeve, is guided by the inner sleeve to the vicinity of the jet valve to cool the jet valve, and then returns to cool the space between the small rotating arm and the inner sleeve, and finally returns to the air supply duct in the header box to be extracted by the exhaust fan.

3. The rotary arm type online air preheater dust cleaning device according to claim 1 is characterized in that: The mounting bracket includes an upper bracket and a lower bracket, two rotating bearings are arranged in the middle and upper part of the outer column, an upper hollow shaft is mounted on the rotating bearing, the upper hollow shaft passes through the upper end of the outer column and is fixedly connected to the upper bracket; the fixed hollow shaft is installed in the middle and lower part of the outer column through two rotating bearings, the lower end of the fixed hollow shaft passes through the lower end of the outer column and is fixedly connected to the lower bracket, so that the outer column rotates around the upper hollow shaft and the fixed hollow shaft between the upper bracket and the lower bracket, and the junction box swings following the operation of the outer column.

4. The rotary arm type online air preheater dust cleaning device according to claim 1 is characterized in that: The surface of the rotary arm type online air preheater cleaning device is coated with a heat insulating material.

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