Soot blowing system, secondary air system and front and back wall opposed firing boiler

Abstract

The invention relates to a soot blowing system, a secondary air system and a front-back wall opposed firing boiler, the soot blowing system comprises a gas guide pipe, a switch valve, a plurality of first sound wave soot blowers and a plurality of second sound wave soot blowers, the gas guide pipe comprises a first pipe section and a second pipe section which are communicated with each other, the first pipe section is communicated with a primary air pipe of the front-back wall opposed firing boiler, and the second pipe section is communicated with a secondary air pipe of the front-back wall opposed firing boiler. The second pipe section is arranged in the secondary air box, the switch valve is arranged on the first pipe section, an air inlet of each first sound wave soot blower is communicated with the second pipe section, the first sound wave soot blowers are arranged in the first part and correspond to the multiple air outlets in the first part in a one-to-one mode, and each first sound wave soot blower is arranged below the corresponding air outlet. And a sound wave guide pipe of each first sound wave soot blower faces upwards, an air inlet of each second sound wave soot blower communicates with the second pipe section, the second sound wave soot blowers are located at the intersections of the interiors of the first parts and the interiors of the second parts, and sound wave guide pipes of the second sound wave soot blowers incline towards the direction close to the air outlet.

Description

Technical Field

[0001] The present disclosure relates to the technical field of secondary air box soot cleaning, and in particular to a soot blowing system, a secondary air system and a front and rear wall counter-combustion boiler. Background Art

[0002] The secondary air box is an important component of the front and rear wall counter-combustion boiler. Its function is to distribute the secondary air entering the furnace. However, during the actual operation of the boiler, a large amount of dust will gradually accumulate in the secondary air box, which will increase the resistance of the secondary air flowing through the secondary air box and cause the pressure of the secondary air entering the furnace to drop, resulting in a series of problems such as increased power required for the secondary air supply, incomplete combustion in the furnace, and affecting the thermal efficiency of the boiler. Therefore, it is very necessary to clean the dust in the secondary air box regularly.

[0003] In the prior art, it is usually necessary to manually clean the dust deposited in the secondary air box, the dust attached to the inner surface and the dust that is difficult to be carried by the airflow when the boiler is shut down for maintenance. However, this cleaning method has certain personal safety risks and relies on the timing of the boiler being shut down for maintenance, and cannot timely guarantee the air supply capacity of the secondary air box. Summary of the invention

[0004] The purpose of the present disclosure is to provide a soot blowing system, a secondary air system and a front and rear wall counter-combustion boiler to solve the above technical problems.

[0005] In order to achieve the above-mentioned object, according to a first aspect of the present disclosure, a sootblowing system is provided, which is used for a secondary wind box of a front and rear wall hedging boiler, wherein the secondary wind box has a first portion adjacent to a furnace front wall or a furnace rear wall and a second portion adjacent to a furnace side wall, and the sootblowing system comprises an air guide pipe, a switch valve, a plurality of first sonic sootblower and a plurality of second sonic sootblower; The air guide pipe includes a first pipe section and a second pipe section that are connected to each other, the first pipe section is used to be arranged outside the secondary wind box and connected to the primary wind pipe of the front and rear wall counter-boiler, the second pipe section is used to be arranged inside the secondary wind box, and the switch valve is arranged on the first pipe section; The air inlet of each of the first sonic soot blowers is communicated with the second pipe section, the plurality of the first sonic soot blowers are used to be arranged inside the first part and are arranged one-to-one corresponding to the plurality of air outlets on the first part, each of the first sonic soot blowers is used to be arranged below the corresponding air outlet, and the sonic waveguide of each of the first sonic soot blowers is arranged upward; The air inlet of each of the second sonic soot blowers is connected to the second pipe section, the second sonic soot blowers are used to be arranged at the intersection of the interior of the first part and the interior of the second part, and the sonic waveguide tube of the second sonic soot blower is inclined toward the direction close to the air outlet.

[0006] Optionally, the vertical distance between the sonic waveguide of the first sonic sootblower and the corresponding air outlet is set to 1.5m-2m, and the horizontal distance between the sonic waveguide of the first sonic sootblower and the corresponding air outlet is set to 0.5m-0.8m; The angle between the sonic waveguide of the second sonic sootblower and the horizontal direction is set to be 30° to 45°.

[0007] Optionally, the first sonic soot blower and the second sonic soot blower are both configured to generate sonic waves with a frequency of 30 Hz to 260 Hz.

[0008] Optionally, the sootblowing system further comprises a controller and a plurality of pressure sensors, wherein the plurality of pressure sensors are arranged inside the first part and used to detect the pressure inside the first part, and the switch valve and the plurality of pressure sensors are electrically connected to the controller.

[0009] Optionally, the air duct is multiple and includes a first air duct and a second air duct, and the switch valve is multiple and includes a first switch valve and a second switch valve; The first switch valve is arranged on the first pipe section of the first air duct, the second switch valve is arranged on the first pipe section of the second air duct, the second pipe section of the first air duct and the second pipe section of the second air duct both extend along the length direction of the first part and are symmetrically arranged about the vertical center line of the first part; The first sonic soot blower and the second sonic soot blower are both arranged on the second pipe section of the first air duct and the second pipe section of the second air duct.

[0010] Optionally, the sootblowing system further comprises a controller and a plurality of pressure sensors, the plurality of pressure sensors are used to be arranged inside the first part, and the plurality of pressure sensors, the first switch valve, and the second switch valve are all electrically connected to the controller; The plurality of pressure sensors include a first pressure sensor, a second pressure sensor, a third pressure sensor, and a fourth pressure sensor, wherein the first pressure sensor and the second pressure sensor are arranged close to the second pipe section of the first air duct, and the first pressure sensor and the second pressure sensor are arranged at intervals along the flow direction of the secondary air in the first part, and the third pressure sensor and the fourth pressure sensor are arranged close to the second pipe section of the second air duct, and the third pressure sensor and the fourth pressure sensor are arranged at intervals along the flow direction of the secondary air in the first part; The controller is used to control the first switch valve to open when the absolute value of the difference between the pressure detected by the first pressure sensor and the pressure detected by the second pressure sensor is greater than or equal to a first preset pressure difference, and to control the first switch valve to close when the absolute value of the difference between the pressure detected by the first pressure sensor and the pressure detected by the second pressure sensor is less than the first preset pressure difference; The controller is also used to control the second switch valve to open when the absolute value of the difference between the pressure detected by the third pressure sensor and the pressure detected by the fourth pressure sensor is greater than or equal to a second preset pressure difference, and to control the second switch valve to close when the absolute value of the difference between the pressure detected by the third pressure sensor and the pressure detected by the fourth pressure sensor is less than the second preset pressure difference.

[0011] Optionally, the sootblowing system further comprises a cyclone separator, and the cyclone separator is arranged on the first pipe section.

[0012] Optionally, the sootblowing system further comprises a check valve and a filter, wherein the check valve and the filter are both arranged on the first pipe section, the filter is located upstream of the switch valve, and the check valve is located upstream of the filter.

[0013] According to a second aspect of the present disclosure, there is provided a secondary air system for a front and rear wall counter-boiler, the secondary air system comprising a secondary air box and the above-mentioned sootblowing system, the secondary air box having a first part for being adjacent to a furnace front wall or a furnace rear wall and a second part for being adjacent to a furnace side wall.

[0014] According to a third aspect of the present disclosure, a front and rear wall opposed combustion boiler is provided, comprising a primary air duct, a furnace and the above-mentioned secondary air system, the furnace comprising a furnace front wall, a furnace rear wall and a furnace side wall located between the furnace front wall and the furnace rear wall, the first portion is adjacent to the furnace front wall or the furnace rear wall, the second portion is adjacent to the furnace side wall, and the first pipe section of the air guide duct is connected to the primary air duct.

[0015] Through the above technical scheme, the first pipe section can be connected to the primary air duct, and the second pipe section can be arranged inside the secondary air box. When the secondary air box needs to be sootblown, the switch valve arranged on the first pipe section can be opened, so that the primary air in the primary air duct can enter the air inlets of multiple first sonic soot blowers and the air inlets of multiple second sonic soot blowers through the first pipe section and the second pipe section, thereby driving the multiple first sonic soot blowers and the multiple second sonic soot blowers to work. Since the sonic waveguide of the sonic soot blower can emit high-energy sound waves, the high-energy sound waves form a multi-directional sound field between the inner walls of the secondary air box in the form of direct radiation, reflection, diffraction, etc., which will peel off the dust attached to the inner surface of the secondary air box, and the secondary air will carry the peeled dust and send it into the furnace of the boiler through the air outlet, thereby realizing the cleaning of the inside of the secondary air box.

[0016] Furthermore, since a plurality of first sonic soot blowers are used to be arranged inside the first part and are arranged one-to-one corresponding to the plurality of air outlets on the first part, each first sonic soot blower is used to be arranged below the corresponding air outlet, so that the first sonic soot blower can generate a stronger sound field below the air outlet, and the sound waveguide of each first sonic soot blower is arranged upward, so that the sound waves emitted by the first sonic soot blower can lift the dust deposited below the air outlet and the dust blown to the bottom of the air outlet by the secondary air to a height close to the air outlet, thereby making it easier for the secondary air to send the dust into the air outlet, which is beneficial to improving the cleaning effect inside the secondary air box.

[0017] In addition, due to the structure of the secondary air box, the volume of secondary air flowing through the intersection of the interior of the first part and the interior of the second part (i.e., the corner inside the secondary air box) is usually small. The air inlet of each second sonic soot blower in the present invention is connected to the second pipe section, and the second sonic soot blower is used to be arranged at the intersection of the interior of the first part and the interior of the second part, so that the second sonic soot blower can generate a stronger sound field at the corner inside the secondary air box, and the sonic waveguide of the second sonic soot blower is inclined in the direction close to the air outlet, so that the sound waves emitted by the second sonic soot blower can more easily loosen the dust deposited at the corner, thereby helping to improve the cleaning ability at the corner inside the secondary air box, and further helping to further improve the cleaning effect inside the secondary air box.

[0018] In summary, compared with the prior art method that requires manual cleaning when the boiler is shut down for maintenance, the soot blowing system disclosed in the present invention can replace manual work to clean the dust deposited inside the secondary air box, the dust attached to the inner surface and the dust that is difficult to be carried by the airflow, thereby helping to avoid personal safety risks. Moreover, the soot blowing system does not need to wait for the boiler to be shut down when cleaning, thereby timely ensuring the air supply capacity of the secondary air box.

[0019] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings: Figure 1 It is a partial three-dimensional structural perspective view of a sootblowing system provided in one embodiment of the present disclosure.

[0021] Figure 2 It is a flow chart of a secondary air system provided in one embodiment of the present disclosure.

[0022] Figure 3 It is a top view of a front and rear wall counter-combustion boiler provided in one embodiment of the present disclosure.

[0023] Description of Reference Numerals 100-sootblowing system; 10-air duct; 11-first pipe section; 12-second pipe section; 13-first air duct; 14-second air duct; 20-on / off valve; 21-first on / off valve; 22-second on / off valve; 31-first sonic sootblower; 32-second sonic sootblower; 50-pressure sensor; 51-first pressure sensor; 52-second pressure sensor; 53-third pressure sensor; 54-fourth pressure sensor; 60-cyclone separator; 70-check valve; 80-filter; 200-secondary air system; 210-secondary air box; 201-first part; 202-second part; 203-air outlet; 204-air inlet; 300-front and rear wall counter-combustion boiler; 310-furnace front wall; 320-furnace rear wall; 330-furnace side wall; 340-primary air duct. DETAILED DESCRIPTION

[0024] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0025] In the present disclosure, unless otherwise stated, the directional words used, such as "upper, lower, top, bottom, vertical, horizontal" are generally defined by the upper, lower, top, bottom, vertical, and horizontal positions of the secondary air box in normal use (for details, please refer to Figure 1), is only for the convenience of describing the present disclosure and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, a specific orientation structure and operation, and therefore cannot be understood as limiting the present disclosure. "Inside and outside" refer to the inside and outside of the corresponding component outline. In addition, the terms "first", "second", etc. used are to distinguish one element from another, and do not have order and importance.

[0026] In the description of the present disclosure, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "connected", and "installed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0027] like Figures 1 to 3 As shown, according to the first aspect of the present disclosure, a sootblowing system 100 is provided, which is used for a secondary wind box 210 of a front and rear wall counter-hedge boiler, the secondary wind box 210 having a first portion 201 adjacent to a furnace front wall 310 or a furnace rear wall 320 and a second portion 202 adjacent to a furnace side wall 330, the sootblowing system 100 comprises an air guide pipe 10, a switch valve 20, a plurality of first sonic soot blowers 31 and a plurality of second sonic soot blowers 32, the air guide pipe 10 comprises a first pipe section 11 and a second pipe section 12 which are interconnected, the first pipe section 11 being used to be arranged outside the secondary wind box 210 and being connected to a primary wind duct 340 of the front and rear wall counter-hedge boiler, the second pipe section 12 being used to be arranged inside the secondary wind box 210, the switch valve 20 being provided It is arranged on the first pipe section 11, and the air inlet of each first sonic soot blower 31 is connected with the second pipe section 12. Multiple first sonic soot blowers 31 are used to be arranged inside the first part 201 and are arranged one by one with the multiple air outlets 203 on the first part 201. Each first sonic soot blower 31 is used to be arranged below the corresponding air outlet 203, and the sound waveguide of each first sonic soot blower 31 is arranged upward. The air inlet of each second sonic soot blower 32 is connected with the second pipe section 12. The second sonic soot blower 32 is used to be arranged at the intersection of the interior of the first part 201 and the interior of the second part 202, and the sound waveguide of the second sonic soot blower 32 is inclined toward the direction close to the air outlet 203.

[0028] Through the above technical scheme, the first pipe section 11 can be connected to the primary air duct 340, and the second pipe section 12 can be arranged inside the secondary air box 210. When the secondary air box 210 needs to be sootblown, the switch valve 20 arranged on the first pipe section 11 can be opened, so that the primary air in the primary air duct 340 can enter the air inlets of multiple first sonic soot blowers 31 and multiple second sonic soot blowers 32 through the first pipe section 11 and the second pipe section 12, thereby driving the multiple first sonic soot blowers 31 and multiple second sonic soot blowers 32 to work. Since the sonic waveguide of the sonic soot blower can emit high-energy sound waves, the high-energy sound waves form a multi-directional sound field between the inner walls of the secondary air box 210 in the form of direct radiation, reflection, diffraction, etc., which will peel off the dust attached to the inner surface of the secondary air box 210, and the secondary air will carry the peeled dust and send it into the furnace of the boiler through the air outlet 203, so as to realize the soot cleaning of the inside of the secondary air box 210.

[0029] Furthermore, since a plurality of first sonic soot blowers 31 are used to be arranged inside the first part 201 and are arranged one-to-one corresponding to a plurality of air outlets 203 on the first part 201, each first sonic soot blower 31 is used to be arranged below the corresponding air outlet 203, so that the first sonic soot blower 31 can generate a stronger sound field below the air outlet 203, and the sound waveguide tube of each first sonic soot blower 31 is arranged upward, so that the sound waves emitted by the first sonic soot blower 31 can lift the dust deposited below the air outlet 203 and the dust blown to the bottom of the air outlet 203 by the secondary air to a height close to the air outlet 203, thereby making it easier for the secondary air to send the dust into the air outlet 203, which is beneficial to improve the cleaning effect on the inside of the secondary air box 210.

[0030] In addition, since the volume of secondary air flowing through the intersection of the interior of the first part 201 and the interior of the second part 202 (i.e., the corner inside the secondary air box 210) is usually small, the air inlet of each second sonic soot blower 32 in the present disclosure is connected to the second pipe section 12, and the second sonic soot blower 32 is used to be arranged at the intersection of the interior of the first part 201 and the interior of the second part 202, so that the second sonic soot blower 32 can generate a stronger sound field at the corner inside the secondary air box 210, and the sound waveguide tube of the second sonic soot blower 32 is inclined toward the direction close to the air outlet 203, so that the sound waves emitted by the second sonic soot blower 32 can more easily loosen the dust deposited at the corner, thereby helping to improve the cleaning ability at the corner inside the secondary air box 210, and further helping to further improve the cleaning effect inside the secondary air box 210.

[0031] In summary, compared with the prior art method that requires manual cleaning when the boiler is shut down for maintenance, the sootblowing system 100 disclosed in the present invention can replace manual work to clean the dust deposited inside the secondary air box 210, the dust attached to the inner surface and the dust that is difficult to be carried by the airflow, thereby helping to avoid personal safety risks. In addition, the sootblowing system 100 does not need to wait for the boiler to be shut down when cleaning, thereby ensuring the air supply capacity of the secondary air box 210 in a timely manner.

[0032] It is understandable that the air outlet 203 refers to the opening through which the secondary air box 210 communicates with the furnace, and is not limited to a specific opening formed on the secondary air box 210 .

[0033] It should be noted that the sonic soot blower usually includes a sonic wave generator and a sonic waveguide. The sonic wave generator can convert compressed air (primary air in the present disclosure) into high-power sound waves, and then export the sound waves through the sonic waveguide. By adjusting the direction of the sonic waveguide, the direction of the sound waves emitted by the sonic soot blower can be adjusted.

[0034] Here, since the temperature of the primary air is usually 310℃~320℃ and the pressure is usually 8kpa~10kpa, using the primary air as the air source to drive the first sonic soot blower 31 and the second sonic soot blower 32 can meet the working requirements of the sonic soot blowers, and the primary air duct 340 and the secondary air box 210 are close to each other, which can reduce the length of the air duct 10 and save the cost of the air duct 10.

[0035] Optionally, the gas pressure of the first sonic soot blower 31 and the second sonic soot blower 32 may be 0.5 MPa to 0.7 MPa, and the gas volume may be 1.5 m 3 / min~3m 3 / min.

[0036] Alternatively, if Figure 1 and Figure 3 As shown, the secondary air box 210 can form a concave shape together with the first part 201 and the second part 202 located at both ends of the first part 201, the air inlet 204 of the secondary air box 210 can be located in the second part 202, the air outlet 203 of the secondary air box 210 can be located in the first part 201, and the flow direction of the secondary air in the first part 201 can be from the second parts 202 on both sides to the first part 201 in the middle.

[0037] In the present disclosure, the spacing between the sound waveguides of the first sonic soot blower 31 can be set to any suitable value according to actual conditions, and the present disclosure does not limit this. As an implementation mode, the vertical distance between the sound waveguide of the first sonic soot blower 31 and the corresponding air outlet 203 is set to 1.5m~2m, and the horizontal distance between the sound waveguide of the first sonic soot blower 31 and the corresponding air outlet 203 can be set to 0.5m~0.8m. Such a setting is not only conducive to the sound waves emitted by the first sonic soot blower 31 to lift the dust to the air outlet 203, but also conducive to the sound waves emitted by the first sonic soot blower 31 to loosen the dust at the bottom of the first part 201.

[0038] The present disclosure does not limit the inclination angle of the acoustic waveguide of the second acoustic wave sootblower 32. As an embodiment, the angle between the acoustic waveguide of the second acoustic wave sootblower 32 and the horizontal direction can be set to 30° to 45°. The acoustic waveguide of the second acoustic wave sootblower 32 is set to this angle, which is conducive to improving the ability of the acoustic wave emitted by the second acoustic wave sootblower 32 to remove dust at the corner.

[0039] In order to further improve the dust removal capability of the first sonic soot blower 31 and the second sonic soot blower 32, as an embodiment, the first sonic soot blower 31 and the second sonic soot blower 32 are both configured to generate sound waves with a frequency of 30 Hz to 260 Hz. The first sonic soot blower 31 and the second sonic soot blower 32 emit sound waves of this frequency, which can efficiently remove dust attached to the inner surface of the secondary air box 210.

[0040] Optionally, the first sonic soot blower 31 and the second sonic soot blower 32 are both configured to generate sonic waves with an intensity of 130 dB to 150 dB.

[0041] In order to reduce the operating burden of the sootblowing system 100, as an embodiment, Figure 2 As shown, the sootblowing system 100 also includes a controller and a plurality of pressure sensors 50, the plurality of pressure sensors 50 are used to be arranged inside the first part 201, and are used to detect the pressure inside the first part 201, and the switch valve 20 and the plurality of pressure sensors 50 are electrically connected to the controller. When the pressure inside the secondary air box 210 rises, it may mean that the dust accumulation inside the secondary air box 210 increases. At this time, the pressure signal detected by the pressure sensor 50 is transmitted to the controller, and then the controller controls the switch valve 20 to open, so that the primary air can enter the air inlet of the first sonic sootblower 31 and the air inlet of the second sonic sootblower 32, so that the first sonic sootblower 31 and the second sonic sootblower 32 emit sound waves to clean the inside of the secondary air box 210. Since the above process does not require manual intervention, it is helpful to reduce the operating burden of the sootblowing system 100.

[0042] Alternatively, if Figure 1 and Figure 2 As shown, there are multiple air ducts 10 including a first air duct 13 and a second air duct 14, there are multiple switch valves 20 including a first switch valve 21 and a second switch valve 22, the first switch valve 21 is arranged on the first pipe segment 11 of the first air duct 13, and the second switch valve 22 is arranged on the first pipe segment 11 of the second air duct 14, the second pipe segment 12 of the first air duct 13 and the second pipe segment 12 of the second air duct 14 both extend along the length direction of the first part 201 and are symmetrically arranged about the vertical center line of the first part 201, and the second pipe segment 12 of the first air duct 13 and the second pipe segment 12 of the second air duct 14 are both provided with a first sonic soot blower 31 and a second sonic soot blower 32. That is to say, the first air duct 13 and the second air duct 14 are connected in parallel, and the first sonic soot blower 31 and the second sonic soot blower 32 are respectively arranged on the first air duct 13 and the second air duct 14, so as to ensure the consistency of the air volume and pressure of the primary air entering different first sonic soot blowers 31 and different second sonic soot blowers 32, and further ensure the consistency of the soot cleaning effect of the soot blowing system 100 on various places in the secondary air box 210. The first switch valve 21 is arranged on the first pipe section 11 of the first air duct 13, and the second switch valve 22 is arranged on the first pipe section 11 of the second air duct 14. Therefore, the first switch valve 21 and the second switch valve 22 can be controlled respectively to realize the selective soot cleaning of some areas in the secondary air box 210, so as to reduce the energy consumption of the soot blowing system 100 for soot cleaning.

[0043] Since the secondary air required by the furnace under different working conditions is different, the wind pressure of the secondary air in the secondary air box 210 under different working conditions is also different. In order to solve this problem, as an implementation method, Figure 2As shown, the sootblowing system 100 also includes a controller and a plurality of pressure sensors 50, the plurality of pressure sensors 50 are used to be arranged inside the first part 201, the plurality of pressure sensors 50, the first switch valve 21, and the second switch valve 22 are all electrically connected to the controller, the plurality of pressure sensors 50 include a first pressure sensor 51, a second pressure sensor 52, a third pressure sensor 53, and a fourth pressure sensor 54, the first pressure sensor 51 and the second pressure sensor 52 are arranged near the second pipe section 12 of the first air duct 13, and the first pressure sensor 51 and the second pressure sensor 52 are arranged at intervals along the flow direction of the secondary air in the first part 201, the third pressure sensor 53 and the fourth pressure sensor 54 are arranged near the second pipe section 12 of the second air duct 14, and the third pressure sensor 53 and the fourth pressure sensor 54 are arranged along the flow direction of the secondary air in the first part 201 The flow direction intervals in the first part 201 are set, and the controller is used to control the first switch valve 21 to open when the absolute value of the difference between the pressure detected by the first pressure sensor 51 and the pressure detected by the second pressure sensor 52 is greater than or equal to the first preset pressure difference, and to control the first switch valve 21 to close when the absolute value of the difference between the pressure detected by the first pressure sensor 51 and the pressure detected by the second pressure sensor 52 is less than the first preset pressure difference. The controller is also used to control the second switch valve 22 to open when the absolute value of the difference between the pressure detected by the third pressure sensor 53 and the pressure detected by the fourth pressure sensor 54 is greater than or equal to the second preset pressure difference, and to control the second switch valve 22 to close when the absolute value of the difference between the pressure detected by the third pressure sensor 53 and the pressure detected by the fourth pressure sensor 54 is less than the second preset pressure difference.

[0044] Since the multiple air outlets 203 of the secondary air box 210 are usually arranged at intervals along the length direction of the first part 201, and the secondary air usually flows in the first part 201 along the length direction of the first part 201, therefore, the wind pressure will gradually decrease during the flow of the secondary air in the first part 201, and the first pressure sensor 51 and the second pressure sensor 52 are arranged close to the second pipe section 12 of the first air duct 13, and the first pressure sensor 51 and the second pressure sensor 52 are arranged at intervals along the flow direction of the secondary air in the first part 201, so that the difference between the pressure detected by the first pressure sensor 51 and the pressure detected by the second pressure sensor 52 can reflect the degree of dust accumulation near the second pipe section 12 of the first air duct 13, and the difference is not affected by changes in operating conditions. When the absolute value of the difference is less than the first preset pressure difference, it means that there is a lot of dust accumulation near the second pipe section 12 of the first air duct 13, and the first switch valve 21 can be controlled by the controller to open, so that the first sonic soot blower 31 and the second sonic soot blower 32 on the second pipe section 12 of the first air duct 13 can clean the nearby dust.

[0045] Similarly, by arranging the third pressure sensor 53 and the fourth pressure sensor 54 close to the second pipe section 12 of the second air duct 14, and the third pressure sensor 53 and the fourth pressure sensor 54 are arranged at intervals along the flow direction of the secondary air in the first part 201, the difference between the pressure detected by the third pressure sensor 53 and the pressure detected by the fourth pressure sensor 54 can reflect the degree of dust accumulation near the second pipe section 12 of the second air duct 14, and the difference is not affected by changes in operating conditions. When the absolute value of the difference is less than the second preset pressure difference, it means that there is a lot of dust accumulation near the second pipe section 12 of the second air duct 14, and the second switch valve 22 can be controlled to open by the controller, so that the first sonic soot blower 31 and the second sonic soot blower 32 on the second pipe section 12 of the second air duct 14 can clean the nearby dust.

[0046] In order to prevent dust impurities in the primary air from clogging or damaging the sootblowing system 100, as an embodiment, Figure 2 As shown, the sootblowing system 100 further includes a cyclone separator 60, which is disposed on the first pipe section 11. The cyclone separator 60 can separate dust impurities in the primary air, thereby reducing the possibility of dust impurities in the primary air clogging or damaging the sootblowing system 100.

[0047] In addition, since the cyclone separator 60 has a certain volume, the cyclone separator 60 can also buffer the primary wind and stabilize the wind pressure flowing to the second pipe section 12, which is beneficial to ensure the working stability of the first sonic soot blower 31 and the second sonic soot blower 32.

[0048] Here, optionally, the diameter of the cavity of the cyclone separator 60 may be 270 mm to 320 mm, the height of the cavity of the cyclone separator 60 may be 350 mm to 400 mm, and the diameter of the ash discharge port may be 90 mm to 100 mm.

[0049] Alternatively, if Figure 2 As shown, the sootblowing system 100 further includes a check valve 70 and a filter 80, both of which are arranged on the first pipe section 11, the filter 80 is located upstream of the switch valve 20, and the check valve 70 is located upstream of the filter 80. By arranging the filter 80 on the first pipe section 11, it is beneficial to further reduce dust impurities in the primary air, thereby facilitating the service life of the first sonic sootblower 31 and the second sonic sootblower 32, and arranging the check valve 70 on the first pipe section 11 can prevent the airflow from flowing back through the second pipe section 12 and the first pipe section 11, affecting the primary air duct 340 and its related equipment.

[0050] According to a second aspect of the present disclosure, Figure 1As shown, a secondary air system 200 is provided for a front and rear wall hedging boiler. The secondary air system 200 includes a secondary air box 210 and the above-mentioned sootblowing system 100. The secondary air box 210 has a first part 201 for being adjacent to the furnace front wall 310 or the furnace rear wall 320 and a second part 202 for being adjacent to the furnace side wall 330.

[0051] According to the third aspect of the present disclosure, a front and rear wall counter-combustion boiler 300 is provided, comprising a primary air duct 340, a furnace and the above-mentioned secondary air system 200, wherein the furnace comprises a furnace front wall 310, a furnace rear wall 320 and a furnace side wall 330 located between the furnace front wall 310 and the furnace rear wall 320, the first portion 201 is adjacent to the furnace front wall 310 or the furnace rear wall 320, the second portion 202 is adjacent to the furnace side wall 330, and the first pipe section 11 of the air guide duct 10 is connected to the primary air duct 340.

[0052] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0053] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0054] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A sootblowing system, used for a secondary wind box of a boiler with front and rear walls, wherein the secondary wind box has a first portion adjacent to the front wall or the rear wall of the furnace and a second portion adjacent to the side wall of the furnace, characterized in that: The sootblowing system comprises an air guide pipe, a switch valve, a plurality of first sonic sootblowers and a plurality of second sonic sootblowers; The air guide pipe includes a first pipe section and a second pipe section that are connected to each other, the first pipe section is used to be arranged outside the secondary wind box and connected to the primary wind pipe of the front and rear wall counter-boiler, the second pipe section is used to be arranged inside the secondary wind box, and the switch valve is arranged on the first pipe section; The air inlet of each of the first sonic soot blowers is communicated with the second pipe section, the plurality of the first sonic soot blowers are used to be arranged inside the first part and are arranged one-to-one corresponding to the plurality of air outlets on the first part, each of the first sonic soot blowers is used to be arranged below the corresponding air outlet, and the sonic waveguide of each of the first sonic soot blowers is arranged upward; The air inlet of each of the second sonic soot blowers is connected to the second pipe section, the second sonic soot blowers are used to be arranged at the intersection of the interior of the first part and the interior of the second part, and the sonic waveguide tube of the second sonic soot blower is inclined toward the direction close to the air outlet.

2. The sootblowing system according to claim 1, characterized in that: The vertical distance between the acoustic waveguide of the first acoustic wave sootblower and the corresponding air outlet is set to 1.5m-2m, and the horizontal distance between the acoustic waveguide of the first acoustic wave sootblower and the corresponding air outlet is set to 0.5m-0.8m; The angle between the sonic waveguide of the second sonic sootblower and the horizontal direction is set to be 30° to 45°.

3. The sootblowing system according to claim 1, characterized in that: The first sonic soot blower and the second sonic soot blower are both configured to generate sonic waves with a frequency of 30 Hz to 260 Hz.

4. The sootblowing system according to claim 1, characterized in that: The sootblowing system further comprises a controller and a plurality of pressure sensors, wherein the plurality of pressure sensors are arranged inside the first part and used to detect the pressure inside the first part, and the switch valve and the plurality of pressure sensors are both electrically connected to the controller.

5. The sootblowing system according to claim 1, characterized in that: The plurality of air guide tubes include a first air guide tube and a second air guide tube, and the plurality of switch valves include a first switch valve and a second switch valve; The first switch valve is arranged on the first pipe section of the first air duct, the second switch valve is arranged on the first pipe section of the second air duct, the second pipe section of the first air duct and the second pipe section of the second air duct both extend along the length direction of the first part and are symmetrically arranged about the vertical center line of the first part; The first sonic soot blower and the second sonic soot blower are both arranged on the second pipe section of the first air duct and the second pipe section of the second air duct.

6. The sootblowing system according to claim 5, characterized in that: The sootblowing system further includes a controller and a plurality of pressure sensors, wherein the plurality of pressure sensors are used to be arranged inside the first part, and the plurality of pressure sensors, the first switch valve, and the second switch valve are all electrically connected to the controller; The plurality of pressure sensors include a first pressure sensor, a second pressure sensor, a third pressure sensor, and a fourth pressure sensor, wherein the first pressure sensor and the second pressure sensor are arranged close to the second pipe section of the first air duct, and the first pressure sensor and the second pressure sensor are arranged at intervals along the flow direction of the secondary air in the first part, and the third pressure sensor and the fourth pressure sensor are arranged close to the second pipe section of the second air duct, and the third pressure sensor and the fourth pressure sensor are arranged at intervals along the flow direction of the secondary air in the first part; The controller is used to control the first switch valve to open when the absolute value of the difference between the pressure detected by the first pressure sensor and the pressure detected by the second pressure sensor is greater than or equal to a first preset pressure difference, and to control the first switch valve to close when the absolute value of the difference between the pressure detected by the first pressure sensor and the pressure detected by the second pressure sensor is less than the first preset pressure difference; The controller is also used to control the second switch valve to open when the absolute value of the difference between the pressure detected by the third pressure sensor and the pressure detected by the fourth pressure sensor is greater than or equal to a second preset pressure difference, and to control the second switch valve to close when the absolute value of the difference between the pressure detected by the third pressure sensor and the pressure detected by the fourth pressure sensor is less than the second preset pressure difference.

7. The sootblowing system according to any one of claims 1 to 6, characterized in that: The sootblowing system further includes a cyclone separator, which is disposed on the first pipe section.

8. The sootblowing system according to any one of claims 1 to 6, characterized in that: The sootblowing system further comprises a check valve and a filter, wherein the check valve and the filter are both arranged on the first pipe section, the filter is located upstream of the switch valve, and the check valve is located upstream of the filter.

9. A secondary air system for a front and rear wall counter-heating boiler, characterized in that: The secondary air system comprises a secondary air box and the sootblowing system according to any one of claims 1 to 8, wherein the secondary air box has a first portion for being adjacent to a furnace front wall or a furnace rear wall and a second portion for being adjacent to a furnace side wall.

10. A front and rear wall counter-combustion boiler, characterized in that: It includes a primary air duct, a furnace and the secondary air system as described in claim 9, the furnace includes a furnace front wall, a furnace rear wall and a furnace side wall located between the furnace front wall and the furnace rear wall, the first part is adjacent to the furnace front wall or the furnace rear wall, the second part is adjacent to the furnace side wall, and the first pipe section of the air duct is connected to the primary air duct.

Images