Cold primary air replacement structure of denitration dilution fan

Abstract

The utility model relates to the technical field of denitration devices, discloses a cold primary air replacement structure of a denitration dilution fan, and solves the problem that a pipeline or a nozzle is blocked by accumulated dust in the prior art. The dilution air drives dust accumulated in the dilution air conveying mother pipe to enter the sleeve and be filtered by the filter screen, so that the accumulated dust cannot be blown into a system, normal operation of equipment such as a mixer and a nozzle is ensured, blockage of a pipeline or the nozzle is avoided, and the service life of the pipeline or the nozzle is prolonged. And the first control valve is opened after starting for one minute, the pressure of the air pressure on the elastic sealing assembly is reduced, and the elastic sealing assembly resets to block the lantern ring to avoid backflow.

Description

Technical Field

[0001] The utility model relates to the technical field of off-stock devices, in particular to a cold primary air replacement structure for an off-stock dilution fan. Background Art

[0002] Ammonia dilution fans play a vital role in the denitration system. Its core function is to supply sufficient air volume for the entire denitration process. During operation, the dilution air and ammonia are fully mixed in a special ammonia-air mixer in a specific ratio. This precisely mixed gas enters the SCR (selective catalytic reduction technology) reactor through the injection grid nozzle. In the reactor, the mixed gas reacts with the flue gas. Through this series of processes, the content of nitrogen oxides in the flue gas is effectively reduced, thereby achieving the purpose of flue gas denitration, ensuring that the discharged flue gas meets environmental protection standards, and reducing pollution to the environment.

[0003] The existing application number is 201720465026.2, which discloses an improved ammonia dilution air source system in the denitration system of a thermal power generator set, including an ammonia dilution fan system, a boiler flue gas pipe, an ammonia-air mixer, an injection grid nozzle and an SCR reactor; it also includes a three-way switching baffle and a cold primary air mother pipe, the port I of the three-way switching baffle is connected to the cold primary air mother pipe through a pipeline, and the three-way switching baffle is connected in series in the pipeline between the ammonia dilution fan system and the inlet end of the ammonia-air mixer through ports II and III thereon. The system achieves the purpose of reducing the failure rate and reducing the power consumption rate of the plant by optimizing the dilution air source.

[0004] Regarding the above-mentioned related technologies, during the period when the dilution fan is shut down and in standby mode, dust accumulates in the pipe connected to the fan due to stagnant air flow. When the fan is started again, the dust is blown into the system, affecting the normal operation of equipment such as the mixer and nozzle, and even clogging the pipe or nozzle. Utility Model Content

[0005] The utility model aims to provide a cold primary air replacement structure for an out-of-stock dilution fan, and the device is adopted to work, thereby solving the problem of dust accumulation blocking the pipeline or nozzle.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a cold primary air replacement structure for an out-of-stock dilution fan, comprising a dilution air delivery main pipe and a control valve 1 installed at the output end of the dilution air delivery main pipe, a dust discharge mechanism is installed at the lower end of the dilution air delivery main pipe, a three-way pipe is installed at the end of the control valve 1 away from the dilution air delivery main pipe, the dust discharge mechanism comprises a sleeve and an elastic seal installed at the upper end of the sleeve for connecting with the dilution air delivery main pipe, a sleeve ring is installed in the middle of the sleeve, an elastic sealing assembly is installed on the inner side of the sleeve at the lower end of the sleeve, a filter screen is arranged at the lower end of the sleeve, and a connecting ring is threadedly connected to the lower end of the sleeve. After the dilution fan is started, the control valve 1 is not opened, and the wind pressure pushes the elastic sealing assembly and the sleeve ring to separate to produce a gap, and the dilution air drives the dust accumulated inside the dilution air delivery main pipe into the sleeve and is filtered by the filter screen.

[0007] Furthermore, a control valve 2 is provided on the three-way pipe, a disposable air main pipe is installed at one end of the control valve 2, and two opposite air inlets of the disposable air main pipe are respectively installed with a cold primary air duct A and a cold primary air duct B, and regulating valves are provided at the connection between the cold primary air duct A and the disposable air main pipe and at the connection between the cold primary air duct B and the disposable air main pipe.

[0008] Furthermore, the elastic sealing assembly includes an elastic sealing block and a return spring fixedly installed on the upper inner end of the elastic sealing block for resetting the elastic sealing block. A guide block for stably moving the elastic sealing block is also installed at the lower end of the return spring, and the guide block is movably connected to the elastic sealing block. A support member for supporting the guide block, the return spring and the elastic sealing block is installed at the lower end of the guide block, and the support member is fixedly connected to the sleeve.

[0009] Furthermore, an upper thread groove is provided on the inner side of the upper end of the connecting ring, and an upper thread sleeve is fixedly installed on the lower end of the sleeve, and the upper thread groove matches the thread of the upper thread sleeve.

[0010] Furthermore, the lower end of the connecting ring is threaded with a connecting straight pipe, the lower end of the connecting straight pipe is installed with a bent pipe for turning, the lower end of the bent pipe is installed with an extension pipe for extending the length, and the output end of the extension pipe is installed with a guide pipe for connecting with the lower end of the three-way pipe.

[0011] Furthermore, a lower threaded sleeve is fixedly mounted on the upper end of the connecting straight pipe, a lower threaded groove is provided on the inner side of the lower end of the connecting ring, and the lower threaded sleeve is threadably matched with the lower threaded groove.

[0012] Furthermore, a movable ring is installed at the upper end of the sleeve, and the movable ring is rotatably connected to an inner groove opened on the inner side of the shell wall at the lower end of the connecting tube.

[0013] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0014] The utility model proposes a cold primary air replacement structure for an out-of-stock dilution fan. When the dilution fan is started, the control valve 1 is temporarily not opened. At this time, the air pressure inside the dilution air delivery mother pipe increases, which will push the elastic sealing component and the sleeve ring to separate and produce a gap. Then the dilution wind drives the dust accumulated inside the dilution air delivery mother pipe to enter the sleeve and be filtered by the filter net, so that the accumulated dust will not be blown into the system, ensuring the normal operation of equipment such as the mixer and the nozzle, avoiding clogging of the pipeline or the nozzle. After 2-4 minutes of starting, the control valve 1 is opened again. At this time, the wind pressure reduces the pressure on the elastic sealing component, and the elastic sealing component is reset to seal the sleeve ring to avoid backflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 The overall three-dimensional structure of the utility model is shown in FIG. Figure 1 ;

[0017] Figure 2 The overall three-dimensional structure of the utility model is shown in FIG. Figure 2 ;

[0018] Figure 3 It is a schematic diagram of the three-dimensional structure of the ash discharge mechanism, the extension pipe and the guide pipe of the utility model;

[0019] Figure 4 It is a schematic diagram of the split three-dimensional structure of the ash discharge mechanism of the utility model;

[0020] Figure 5 It is a schematic diagram of the three-dimensional structure of the elastic sealing component of the utility model;

[0021] Figure 6 It is a schematic diagram of the cutaway three-dimensional structure of the ash discharge mechanism of the utility model.

[0022] In the figure: 1. Dilution air delivery main pipe; 2. Control valve 1; 3. Tee pipe; 4. Control valve 2; 5. Cold primary air duct A; 6. Cold primary air duct B; 7. Regulating valve; 8. Sleeve; 81. Connecting pipe; 811. Upper threaded sleeve; 812. Movable ring; 813. Inner groove; 814. Spring; 82. Sleeve ring; 83. Elastic sealing assembly; 831. Elastic blocking block; 832. Reset spring; 833. Guide block; 834. Support member; 84. Connecting ring; 841. Filter screen; 842. Upper threaded groove; 843. Lower threaded groove; 85. Connecting straight pipe; 851. Lower threaded sleeve; 86. Bend pipe; 9. Extension pipe; 91. Guide pipe. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] Example 1

[0025] Combination Figure 1-Figure 2 A cold primary air replacement structure for an out-of-stock dilution fan comprises a dilution air delivery main pipe 1 for delivering dilution air and a control valve 1 2 installed at the output end of the dilution air delivery main pipe 1 for closing the dilution air delivery main pipe 1. The input end of the dilution air delivery main pipe 1 is connected to the dilution fan. A tee pipe 3 is installed at one end of the control valve 1 2 away from the dilution air delivery main pipe 1. One of the two pipe openings of the tee pipe 3 in the same straight line is fixedly connected to the control valve 1 2 and the other is provided with a control valve 2 4. A disposable air main pipe is installed at one end of the control valve 2 4. Two opposite air inlets of the disposable air main pipe are respectively provided with an A cold primary air duct 5 and a B cold primary air duct 6. , the connection between A cold primary air duct 5 and disposable air main pipe and the connection between B cold primary air duct 6 and disposable air main pipe are both provided with regulating valve 7 for adjusting the primary air volume. The dilution fan is stopped, control valve 1 2 closes the dilution air delivery main pipe 1, control valve 2 4 is opened, and regulating valve 7 controls the air volume. Denitrification dilution air is supplied through A and B cold primary air, saving 54,900 yuan in electricity cost each year. In normal operation, the dilution air volume is 4500m³ / h when the unit load is 50%, and the dilution air volume is 5000m³ / h when the unit load is 100%. The minimum dilution air volume exceeds the protection action value of 730m³ / h, the dilution air margin is sufficient, and the operation is stable.

[0026] Combination Figure 2-Figure 4A dust discharge mechanism is installed at the lower end of the dilution air delivery mother pipe 1. The dust discharge mechanism includes a sleeve 8 and a connecting pipe 81 elastically sealed and installed at the upper end of the sleeve 8 for communicating with the dilution air delivery mother pipe 1. A sealing ring 82 is installed in the middle of the sleeve 8. The sleeve 82 is in the shape of a circular ring with both upper and lower sides concave inward. An elastic sealing component 83 for fitting and sealing with the sleeve 82 when the dilution fan is stopped is installed on the inner side of the sleeve 8 at the lower end of the sleeve 8. A filter screen 841 is provided at the lower end of the sleeve 8. A connecting ring 84 is threadedly connected at the lower end of the sleeve 8 to facilitate replacement of the filter screen 841. The filter screen 841 is detachably installed on the inner side of the connecting ring 84. The connection methods may be bolt connection, glue bonding and snap connection. The mesh size of the filter 841 may be selected according to the needs, preferably between 10-80 meshes. Specifically, when the dilution fan is started, the control valve 2 is temporarily not opened. At this time, the air pressure inside the dilution air delivery mother pipe 1 increases, which in turn pushes the elastic sealing component 83 and the sleeve ring 82 to separate to create a gap. Then the dilution wind drives the dust accumulated inside the dilution air delivery mother pipe 1 to enter the sleeve 8 and be filtered by the filter 841. After 2-4 minutes of starting, the control valve 2 is opened again. At this time, the wind pressure reduces the pressure on the elastic sealing component 83, and the elastic sealing component 83 is reset to seal the sleeve ring 82 to prevent backflow.

[0027] Combination Figure 4-Figure 5 The elastic sealing assembly 83 includes an elastic sealing block 831 and a return spring 832 fixedly installed on the inner upper end of the elastic sealing block 831 for resetting the elastic sealing block 831. The elastic sealing block 831 can be made of soft rubber or plastic, so that it can be squeezed with the ring 82 to form a sealed connection under the resetting pressure of the return spring 832. The lower end of the return spring 832 is also equipped with a guide block 833 for making the elastic sealing block 831 move stably, and the guide block 833 is movably connected to the elastic sealing block 831. The lower end of the guide block 833 is equipped with a support member 834 for supporting the guide block 833, the return spring 832 and the elastic sealing block 831. The support member 834 is fixedly connected to the sleeve 8 through at least two metal tubes. Preferably, four metal tubes are provided to save costs while improving support stability.

[0028] Combination Figure 4 An upper thread groove 842 is provided on the inner side of the upper end of the connecting ring 84, and an upper thread sleeve 811 is fixedly installed on the lower end of the sleeve 8. The upper thread groove 842 matches the thread of the upper thread sleeve 811. The connecting ring 84 is removed by rotating it regularly, and then the filter screen 841 is replaced to ensure that the filter screen 841 can filter normally without being blocked.

[0029] Combination Figure 3-Figure 6In order to solve the problem that the control valve 2 is prone to malfunction due to being closed for a long time, the lower end of the connecting ring 84 is threadedly provided with a connecting straight pipe 85, and the lower end of the connecting straight pipe 85 is installed with a curved pipe 86 for turning, and the lower end of the curved pipe 86 is installed with an extension pipe 9 for extending the length, and the output end of the extension pipe 9 is installed with a guide pipe 91 for connecting with the lower end of the three-way pipe 3. When the air volume of the A and B cold primary air supplying the denitrification dilution air is insufficient, the control valve 2 needs to be opened at this time. At this time, the control valve 2 cannot be opened due to malfunction due to long-term non-use. At this time, the dilution air enters the guide pipe 91 from the casing 8 through the extension pipe 9 and enters the three-way pipe 3 for compensation. While achieving the filtering effect, the problem of insufficient dilution air volume caused by damage to the control valve 2 can be avoided.

[0030] Combination Figure 4 and Figure 6 Furthermore, a lower threaded sleeve 851 is fixedly installed on the upper end of the connecting straight pipe 85, and a lower threaded groove 843 is opened on the inner side of the lower end of the connecting ring 84. The lower threaded sleeve 851 is threadedly matched with the lower threaded groove 843. After the extension pipe 9 and the guide pipe 91 are set, the filter screen 841 needs to be replaced. The connecting ring 84 is rotated to separate it from the lower threaded sleeve 851 and the upper threaded sleeve 811 at the same time. Finally, the connecting ring 84 is removed for easy replacement.

[0031] Combination Figure 4 and Figure 6 Furthermore, in order to compensate for the upward distance of the connecting ring 84 when the thread is removed, a movable ring 812 is installed at the upper end of the sleeve 8, and the movable ring 812 is rotatably connected to the inner groove 813 opened on the inner side of the shell wall of the lower end of the connecting tube 81. When the connecting ring 84 rotates, the connecting ring 84, the sleeve 8 and the movable ring 812 can move upward and rotate in the inner groove 813, which facilitates the removal of the connecting ring 84.

[0032] Combination Figure 6 Furthermore, in order to improve the connection stability between the sleeve 8 and the connecting tube 81 and avoid the problem of excessive noise of the device due to vibration during use, a plurality of springs 814 are installed on the connecting tube 81 located on the inner side of the inner groove 813, and the lower end of the spring 814 is in contact with the movable ring 812. When the equipment is in use, the spring 814 makes the sleeve 8 and the connecting tube 81 tightly connected, and the problem of excessive noise of the device due to vibration will not occur.

[0033] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0034] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cold primary air replacement structure for an out-of-stock dilution fan, comprising a dilution air delivery main pipe (1) and a control valve (2) installed at the output end of the dilution air delivery main pipe (1), a dust discharge mechanism installed at the lower end of the dilution air delivery main pipe (1), and a three-way pipe (3) installed at the end of the control valve (2) away from the dilution air delivery main pipe (1), characterized in that: The dust removal mechanism comprises a sleeve (8) and a connecting pipe (81) elastically sealed and mounted on the upper end of the sleeve (8) for communicating with a dilution air delivery main pipe (1); a sleeve ring (82) is mounted in the middle of the sleeve (8); an elastic sealing assembly (83) is mounted on the inner side of the sleeve (8) located at the lower end of the sleeve ring (82); a filter screen (841) is arranged at the lower end of the sleeve (8); a connecting ring (84) is threadedly connected to the lower end of the sleeve (8); after the dilution fan is started, the control valve 1 (2) is not opened, the wind pressure pushes the elastic sealing assembly (83) and the sleeve ring (82) to separate to generate a gap, and the dilution air drives the dust accumulated inside the dilution air delivery main pipe (1) to enter the sleeve (8) and be filtered by the filter screen (841).

2. The cold primary air replacement structure of the out-of-stock dilution fan according to claim 1 is characterized by: A control valve 2 (4) is provided on the three-way pipe (3), a disposable air main pipe is installed at one end of the control valve 2 (4), and two opposite air inlets of the disposable air main pipe are respectively installed with a cold primary air duct A (5) and a cold primary air duct B (6), and a regulating valve (7) is provided at the connection between the cold primary air duct A (5) and the disposable air main pipe and at the connection between the cold primary air duct B (6) and the disposable air main pipe.

3. The cold primary air replacement structure of the out-of-stock dilution fan according to claim 1 is characterized by: The elastic sealing assembly (83) comprises an elastic sealing block (831) and a return spring (832) fixedly mounted on the inner upper end of the elastic sealing block (831) for returning the elastic sealing block (831); a guide block (833) for making the elastic sealing block (831) move stably is also mounted on the lower end of the return spring (832); the guide block (833) is movably connected to the elastic sealing block (831); a support member (834) for supporting the guide block (833), the return spring (832) and the elastic sealing block (831) is mounted on the lower end of the guide block (833); the support member (834) is fixedly connected to the sleeve (88).

4. The cold primary air replacement structure of the out-of-stock dilution fan according to claim 1 is characterized by: An upper thread groove (842) is provided on the inner side of the upper end of the connecting ring (84), an upper thread sleeve (811) is fixedly mounted on the lower end of the sleeve (8), and the upper thread groove (842) is threadably matched with the upper thread sleeve (811).

5. The cold primary air replacement structure of the out-of-stock dilution fan according to claim 1 is characterized by: The lower end of the connecting ring (84) is provided with a connecting straight pipe (85) through a thread, the lower end of the connecting straight pipe (85) is provided with a curved pipe (86) for turning, the lower end of the curved pipe (86) is provided with an extension pipe (9) for extending the length, and the output end of the extension pipe (9) is provided with a flow guide pipe (91) for communicating with the lower end of the three-way pipe (3).

6. The cold primary air replacement structure of the out-of-stock dilution fan according to claim 5 is characterized by: A lower threaded sleeve (851) is fixedly mounted on the upper end of the connecting straight pipe (85), a lower threaded groove (843) is provided on the inner side of the lower end of the connecting ring (84), and the threads of the lower threaded sleeve (851) and the lower threaded groove (843) are matched.

7. The cold primary air replacement structure of the out-of-stock dilution fan according to claim 6 is characterized by: A movable ring (812) is installed at the upper end of the sleeve (8), and the movable ring (812) is rotatably connected to an inner groove (813) provided on the inner side of the shell wall at the lower end of the connecting tube (81).

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