Swirl burner and system capable of effectively inhibiting high temperature corrosion of boiler furnace side wall

Abstract

The present application provides a swirl burner and its system which can effectively inhibit high-temperature corrosion of the side wall of the boiler furnace, the device includes: a first air duct, which has an inlet and an outlet, and is used to input primary air into the furnace; a second air duct, the second air duct is sleeved outside the first air duct; an annular space is formed between the second air duct and the first air duct; a partition, which is arranged in the annular space, and the partition divides the annular space into a third air duct away from the first air duct and a second air duct located between the first air duct and the third air duct; the second air duct is used to input secondary air into the furnace; the cross-sectional area of ​​the third air duct gradually decreases from the inlet to the outlet to form a nozzle; the end of the third air duct close to the inlet is annular; the end of the third air duct close to the outlet is semi-annular. The embodiment of the present application provides a swirl burner and its system which can effectively inhibit high-temperature corrosion of the side wall of the boiler furnace.

Description

Technical Field

[0001] The present application relates to a swirl burner and a system thereof which can effectively inhibit high-temperature corrosion of a boiler furnace side wall. Background Art

[0002] At present, many power station boilers use the counter combustion system. The counter combustion system includes swirl burners installed on the front and rear walls of the furnace. When the swirl burner is working, the coal powder in the center area burns violently, requiring a large amount of oxygen supply from the outside of the flame. Therefore, the area near the burner flame is generally in an oxygen-deficient state. The side walls of the furnace have no air supply, and a large amount of reducing gases such as CO and H generated by the incomplete combustion of coal powder 2 S will be squeezed to the side wall, thus forming a reducing atmosphere in this area. Therefore, the side wall of the furnace is very prone to high-temperature corrosion, which poses a great safety hazard to the operation of the boiler.

[0003] In the prior art, wall-adhering wind can be used to improve the formation of a reducing atmosphere on the side wall. Specifically, a jet device is first installed on the surface of the side wall. The jet device blows air toward the side wall so that an air film can be formed on the surface of the side wall. The air film can isolate the side wall from the reducing gas, so that the air film can improve the reducing atmosphere. However, the wind direction of the jet device in the prior art is perpendicular to the surface of the side wall, so the wind speed decays relatively quickly, resulting in insufficient rigidity and inability to fully cover the side wall, and it is easy to scour the side wall, thereby accelerating the wear of the side wall. In addition, after adding the wall-adhering wind duct, the flow rate acting on the burner is relatively reduced. Under the same air supply pressure, the pressure of the secondary air box will decrease accordingly, which will cause the coal powder in the burner to fail to burn fully, which not only reduces the efficiency of the boiler but also promotes the formation of a reducing atmosphere in the furnace.

[0004] Therefore, it is necessary to propose a swirl burner and a system thereof that can effectively inhibit high-temperature corrosion of the boiler furnace side wall, so as to solve the above-mentioned problems. Summary of the invention

[0005] In view of this, an embodiment of the present application provides a swirl burner and a system thereof that can effectively suppress high-temperature corrosion of the boiler furnace side wall.

[0006] To achieve the above-mentioned objectives, the present application provides the following technical solutions: a swirl burner, comprising: a first air duct, which has an inlet and an outlet, and is used to input primary air into the furnace; a second air duct, which is sleeved outside the first air duct; an annular space is formed between the second air duct and the first air duct; a partition, which is arranged in the annular space, and the partition divides the annular space into a third air duct away from the first air duct and a second air duct located between the first air duct and the third air duct; the second air duct is used to input secondary air into the furnace; the cross-sectional area of ​​the third air duct gradually decreases from the inlet to the outlet to form a nozzle.

[0007] As a preferred implementation manner, one end of the third air duct close to the inlet is annular; and one end of the third air duct close to the outlet is semi-annular.

[0008] As a preferred implementation, the partition is a tube body, and the tube body is sleeved outside the first air duct; the second air duct is sleeved outside the tube body.

[0009] As a preferred implementation, the cross section of the third air duct along the axial direction extends outwardly obliquely in the direction from the inlet to the outlet.

[0010] As a preferred implementation, the angle between the axial direction of the third air duct and the first air duct is 6 degrees to 12 degrees.

[0011] As a preferred embodiment, a drainage pipe is connected to one end of the second air duct close to the inlet; the drainage pipe is communicated with the annular space; and is used to input secondary air into the third air duct and the second air duct.

[0012] As a preferred embodiment, a baffle for adjusting the airflow in the third air duct and the second air duct is provided in the drainage pipe.

[0013] A swirl combustion system is used for a furnace, the furnace comprising a front water-cooled wall, a rear water-cooled wall and at least one side water-cooled wall located between the front water-cooled wall and the rear water-cooled wall; the swirl combustion system comprises: at least one combustion unit; corresponding to at least one of the side water-cooled walls; the combustion unit comprises two swirl burners as above; the two swirl burners are respectively arranged on the front water-cooled wall and the rear water-cooled wall; and the third air ducts of the two swirl burners are both open toward the corresponding side water-cooled wall, so that the airflow in the third air duct can flow toward the corresponding side water-cooled wall.

[0014] As a preferred embodiment, it also includes: at least one swirl combustion device; arranged on the front water-cooled wall and / or the rear water-cooled wall; the swirl combustion device includes a first air duct, having an inlet and an outlet, for inputting primary air into the furnace; the swirl combustion device is arranged on the side of the swirl burner away from the side water-cooled wall.

[0015] As a preferred embodiment, the third air duct of the swirl burner has an angle with the axial direction of the first air duct, so that the airflows in the third air ducts of the two swirl burners can converge when they do not contact the side water-cooled wall.

[0016] By means of the above technical scheme, the swirl burner and its system described in the embodiment of the present application are provided with a first air duct, a second air duct and a partition, and the cross-sectional area of ​​the third air duct gradually decreases from the inlet to the outlet to form a nozzle; thus, the airflow in the third air duct has strong rigidity when flowing and ejecting in the direction from the inlet to the outlet. This highly rigid airflow can strongly suppress the accumulation of reducing gas on the water-cooled wall on the furnace side, and can also increase the oxygen content of the water-cooled wall on the furnace side, effectively avoiding the formation of a reducing atmosphere in the water-cooled wall area on the furnace side. Therefore, the embodiment of the present application provides a swirl burner and its system that can effectively suppress high-temperature corrosion of the boiler furnace side wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are for explanation purposes only and are not intended to limit the scope of the present application in any way. In addition, the shapes and proportional dimensions of the components in the drawings are only for illustration purposes and are used to help understand the present application. They do not specifically limit the shapes and proportional dimensions of the components of the present application. Under the guidance of the present application, those skilled in the art can select various possible shapes and proportional dimensions to implement the present application according to specific circumstances. In the drawings:

[0018] Figure 1 This is a schematic diagram of the arrangement of the swirl combustion system described in the embodiment of the present application;

[0019] Figure 2 This is a schematic diagram of the arrangement of the swirl combustion system described in the embodiment of the present application on the front water-cooled wall;

[0020] Figure 3 This is a schematic diagram of the outlet end of the swirl burner described in the embodiment of the present application;

[0021] Figure 4 A schematic diagram of a flow channel of a swirl burner according to an embodiment of the present application;

[0022] Figure 5 This is a wind direction diagram of the swirl combustion system in the furnace as described in the embodiment of the present application.

[0023] Description of reference numerals:

[0024] 11. First air duct; 12. Inlet; 13. Outlet; 14. Second air duct; 15. Partition; 17. Third air duct; 19. Second air duct; 21. First air duct; 29. ​​Drain pipe; 31. Baffle; 33. Front water-cooled wall; 35. Rear water-cooled wall; 37. Side water-cooled wall; 39. Swirl burner; 41. Swirl combustion device; 43. Combustion chamber; 45. Flow equalizing tube; 47. Swirl blade; 49. Furnace. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0027] See also Figure 3 , Figure 4 The present embodiment provides a swirl burner 39 that can effectively inhibit high-temperature corrosion of the boiler furnace side wall, including: a first air duct 11, which has an inlet 12 and an outlet 13, and is used to input primary air into the furnace 49; a second air duct 14, which is sleeved outside the first air duct 11; an annular space is formed between the second air duct 14 and the first air duct 11; a partition 15, which is arranged in the annular space, and the partition 15 divides the annular space into a third air duct 17 away from the first air duct 11 and a second air duct 19 located between the first air duct 11 and the third air duct 17; the second air duct 19 is used to input secondary air into the furnace 49; the cross-sectional area of ​​the third air duct 17 gradually decreases from the inlet 12 to the outlet 13 to form a nozzle.

[0028] It can be seen from the above scheme that the swirl burner described in the embodiment of the present application is provided with the first air duct 11, the second air duct 14 and the partition 15, and the cross-sectional area of ​​the third air duct 17 gradually decreases from the inlet 12 to the outlet 13 to form a nozzle; thus, the airflow in the third air duct 17 flows along the direction from the inlet 12 to the outlet 13 and has strong rigidity when it is ejected. This strong rigid airflow can strongly suppress the accumulation of reducing gas on the water-cooled wall 37 on the side of the furnace 49, and can also increase the oxygen content of the water-cooled wall 37 on the side of the furnace 49, effectively avoiding the formation of reducing atmosphere in the water-cooled wall 37 area on the side of the furnace 49.

[0029] like Figure 1 As shown, the furnace 49 described in this embodiment is a boiler furnace 49. The boiler furnace 49 has a combustion chamber 43 for burning coal powder. Specifically, for example, Figure 1 As shown, the furnace 49 is a hollow structure as a whole. The hollow portion forms a combustion chamber 43. Further, the furnace 49 includes a front water-cooled wall 33, a rear water-cooled wall 35, and at least one side water-cooled wall 37 located between the front water-cooled wall 33 and the rear water-cooled wall 35. For example, Figure 1 As shown, the furnace 49 includes two side water-cooled walls 37. Specifically, the two side water-cooled walls 37 include a left side water-cooled wall 37 and a right side water-cooled wall 37. The front water-cooled wall 33, the rear water-cooled wall 35 and the two side water-cooled walls 37 form a combustion chamber 43.

[0030] Furthermore, the swirl burner described in the embodiment of the present application is arranged on the front water-cooled wall 33 or the rear water-cooled wall 35 of the furnace 49, thereby forming a counter-combustion system. Specifically, the swirl burner on the front water-cooled wall 33 corresponds to the swirl burner on the rear water-cooled wall 35, and thus the swirl burner on the front water-cooled wall 33 can input primary air and secondary air into the combustion chamber 43 in the opposite direction to the swirl burner corresponding to it on the rear water-cooled wall 35, thereby causing the coal powder to burn in the combustion chamber 43. This correspondence can be that the number of swirl burners on the front water-cooled wall 33 is equal to the number of swirl burners on the rear water-cooled wall 35. For example Figure 5 A top view of the furnace 49 is shown. Figure 5 It can be seen that there are 8 swirl burners on the front water-cooled wall 33. There are 8 swirl burners on the rear water-cooled wall 35. Of course, the swirl burners on the front water-cooled wall 33 and the rear water-cooled wall 35 are not limited to 8. This application does not stipulate this. The swirl burners on the front water-cooled wall 33 input gas upward, and the swirl burners on the rear water-cooled wall 35 input gas downward, thus forming a counter-combustion system. Furthermore, the swirl burners described in the embodiment of the present application can be fixed to the front water-cooled wall 33 or the rear water-cooled wall 35 of the furnace 49. The fixing method can be, for example, screw fixing, bolt fixing, welding fixing, etc.

[0031] In the present embodiment, the first air duct 11 is used to input primary air into the furnace 49. The primary air is the air sent into the furnace 49 together with the coal powder when the coal powder is burned. The main function of the primary air is to provide air according to the oxygen required by the coal powder during the combustion process in the furnace 49 for the combustion of the furnace 49, and it also has the function of cooling the grate. Specifically, the first air duct 11 has an angle not equal to 0 degrees or 180 degrees with the surface of the front water-cooled wall 33 or the rear water-cooled wall 35. Preferably, the angle between the first air duct 11 and the surface of the front water-cooled wall 33 or the rear water-cooled wall 35 is 90 degrees. That is, the first air duct 11 is arranged perpendicular to the surface of the front water-cooled wall 33 or the rear water-cooled wall 35. Specifically, an opening is provided on the front water-cooled wall 33 or the rear water-cooled wall 35. The first air duct 11 is passed through the opening. Furthermore, a first air duct 21 for the circulation of primary air is formed in the first air duct 11. For example, Figure 4 As shown, the first air duct 11 extends left and right. The first air channel 21 extends left and right. Further, the first air duct 11 has an inlet 12 and an outlet 13. Specifically, the inlet 12 and the outlet 13 are respectively provided at both ends of the first air channel 21. For example, Figure 4 As shown, the left end of the first air duct 21 is the inlet 12. The right end of the first air duct 21 is the outlet 13. Thus, the primary wind energy flows into the first air duct 21 from the inlet 12 and flows out of the first air duct 21 from the outlet 13. Further, the outlet 13 is open toward the combustion chamber 43, so that the primary wind energy is input into the combustion chamber 43 through the outlet 13.

[0032] In this embodiment, the second air duct 14 is sleeved outside the first air duct 11. Further, an annular space is formed between the second air duct 14 and the first air duct 11. Further, a partition 15 is provided in the annular space. Figure 4 As shown, the partition 15 is a tube. Further, the partition 15 divides the annular space into a third air duct 17 away from the first air duct 11 and a second air duct 19 located between the first air duct 11 and the third air duct 17. Figure 4 As shown, the tube body is sleeved outside the first air duct 11. The second air duct 14 is sleeved outside the tube body. In this way, the first air duct 11 and the third air duct 17 are located at the innermost and outermost sides respectively. The second air duct 19 is located in the middle. The second air duct 19 is used to input secondary air into the furnace 49. The secondary air is used to provide oxygen for the coal powder.

[0033] Furthermore, the cross-sectional area of ​​the third air duct 17 gradually decreases from the inlet 12 to the outlet 13 to form a nozzle. Therefore, the airflow in the third air duct 17 has strong rigidity when it is ejected from the inlet 12 to the outlet 13. This strong rigid airflow can strongly inhibit the accumulation of reducing gas on the water-cooled wall 37 on the side of the furnace 49, and can also increase the oxygen content of the water-cooled wall 37 on the side of the furnace 49, effectively avoiding the formation of reducing atmosphere in the water-cooled wall 37 area on the side of the furnace 49. For example, Figure 5 As shown, the third air duct 17 of the swirl burner located on the far left is open to the water-cooled wall on the left, so that when the airflow is ejected from the third air duct 17 along the direction from the inlet 12 to the outlet 13 to the side water-cooled wall 37 on the left, it has strong rigidity, thereby forming a gas barrier on the side water-cooled wall 37 on the left; this can effectively inhibit the reducing swirl gas generated by combustion from diffusing to the side water-cooled wall 37 on the left, reduce the adverse effects of the reducing gas generated by the swirl burner due to combustion on the side water-cooled wall 37 on the left, and alleviate the high-temperature corrosion of the side water-cooled wall 37 of the furnace 49. At the same time, the third air duct 17 is located outside the flame, and can also provide oxygen for combustion, making the combustion more complete. Furthermore, the end of the third air duct 17 close to the inlet 12 is annular; the end of the third air duct 17 close to the outlet 13 is semi-annular. For example, Figure 3 As shown, the left end of the third air duct 17 is annular, and the right end of the third air duct 17 is semi-annular. The cross-sectional area of ​​the third air duct 17 gradually decreases from the left end to the right end to form a nozzle, and the airflow in the third air duct 17 forms an asymmetric peripheral wind.

[0034] Furthermore, since the flame at the outlet 13 of the first air duct 11 will diffuse to a certain extent, in order to avoid the impact on the swirl flame and ensure the stability of combustion, the axial cross section of the third air duct 17 extends outwardly in a direction from the inlet 12 to the outlet 13. Preferably, the angle between the third air duct 17 and the axial direction of the first air duct 11 is 6 degrees to 12 degrees. For example, Figure 4 As shown, the axial direction of the first air duct 11 is the left-right direction. The extension direction of the third air duct 17 is inclined upward from left to right. In this way, when the flame at the outlet 13 of the first air duct 11 spreads upward in the right direction, the third air duct 17 can avoid the impact on the swirl flame. Figure 5 As shown, the axial direction of the first air duct 11 is the up-down direction. And the axial direction of the first air duct 11 is perpendicular to the front water-cooled wall 33 and the rear water-cooled wall 35. The extension direction of the third air duct 17 is inclined to the left in the direction from bottom to top. In this way, when the flame at the outlet 13 of the first air duct 11 spreads to the left in the upward direction, the third air duct 17 can avoid the impact on the swirl flame. That is, the third air duct 17 can reduce the flow cross-section of the asymmetric peripheral wind on the one hand, enhance the rigidity of the asymmetric peripheral wind at the outlet of the third air duct 17, and on the other hand, change the flow direction of the asymmetric peripheral wind, so that the asymmetric peripheral wind flows toward the side water-cooled wall 37 at a certain angle to avoid interference with the swirl flame.

[0035] Furthermore, one end of the second air duct 14 close to the inlet 12 is connected to a drainage pipe 29. Figure 4As shown, the right end of the drainage pipe 29 is connected to the left end of the second air duct 14. The connection method can be screw connection, bolt connection, welding, integral molding, etc. Further, the drainage pipe 29 is connected to the annular space. The drainage pipe 29 is used to input secondary air into the third air duct 17 and the second air duct 19. Further, a baffle 31 is provided in the drainage pipe 29 for adjusting the airflow in the third air duct 17 and the second air duct 19. For example, Figure 4 As shown, the baffle 31 is connected to the partition 15. In this way, the gas in the third air duct 17 mentioned above belongs to the secondary air. The secondary air can be divided through the baffle 31 in the draft tube 29, one stream enters the second air duct 19 to form a swirl to promote combustion, and the other stream enters the third air duct 17 to alleviate high-temperature corrosion. In this way, the swirl burner described in the embodiment of the present application is easy to implement. Specifically, the asymmetric peripheral wind is separated from the secondary air, and no additional pipelines and equipment need to be added, and it can be modified on the original burner equipment. And the swirl burner described in the embodiment of the present application will not interfere with the combustion. Specifically, the asymmetric peripheral wind is separated from the original secondary air, and is located on the outside of the swirl burner and blows toward the side water-cooled wall 37 at a certain angle. It only plays the role of providing oxygen required for combustion and inhibiting the diffusion of reducing gas to the side water-cooled wall 37, and does not impact the flame of the swirl burner and affect its combustion.

[0036] Furthermore, a flow equalizer 45 is provided in both the second air duct 19 and the third air duct 17. The flow equalizer 45 can make the ejected secondary air and the asymmetric peripheral air enter their respective flow ducts in a uniform circular flow form. Furthermore, a swirl blade 47 is provided at one end of the second air duct 19 near the outlet 13. The swirl blade 47 can make the secondary air form a swirl to entrain the low-temperature smoke outside the flame to promote combustion.

[0037] See also Figure 1 , Figure 5 The embodiment of the present application also provides a swirl combustion system, which includes: at least one combustion unit; corresponding to at least one of the side water-cooled walls 37; the combustion unit includes two swirl burners 39 as described above; the two swirl burners 39 are respectively arranged on the front water-cooled wall 33 and the rear water-cooled wall 35; and the third air ducts 17 of the two swirl burners 39 are both open toward the corresponding side water-cooled wall 37, so that the airflow in the third air duct 17 can flow toward the corresponding side water-cooled wall 37.

[0038] It can be seen from the above scheme that the swirl combustion system described in the embodiment of the present application is provided with a combustion unit, and the combustion unit includes two swirl burners 39, so that on the one hand, the two swirl burners 39 form counter combustion, and on the other hand, the third air duct 17 of the swirl burner 39 is open toward the corresponding side water-cooled wall 37, and the cross-sectional area gradually decreases from the inlet 12 to the outlet 13 to form a nozzle; so that the airflow in the third air duct 17 flows along the direction from the inlet 12 to the outlet 13 and is highly rigid when it is ejected. This highly rigid airflow can strongly suppress the accumulation of reducing gas on the water-cooled wall 37 on the side of the furnace 49, and can also increase the oxygen content of the water-cooled wall 37 on the side of the furnace 49, effectively avoiding the formation of a reducing atmosphere in the water-cooled wall 37 area on the side of the furnace 49.

[0039] In this embodiment, the combustion unit includes two swirl burners 39 as described above. That is, the swirl burner 39 includes a first air duct 11, which has an inlet 12 and an outlet 13, for inputting primary air into the furnace 49; a second air duct 14, wherein the first air duct 11 is inserted into the second air duct 14; an annular space is formed between the second air duct 14 and the first air duct 11; a partition 15, which is arranged in the annular space, and the partition 15 divides the annular space into a third air duct 17 away from the first air duct 11 and a second air duct 19 located between the first air duct 11 and the third air duct 17; the second air duct 19 is used to input secondary air into the furnace 49; the cross-sectional area of ​​the third air duct 17 gradually decreases from the inlet 12 to the outlet 13 to form a nozzle. Further, the two swirl burners 39 included in the combustion unit are respectively arranged on the front water-cooled wall 33 and the rear water-cooled wall 35. For example, Figure 1 , Figure 2 , Figure 5 As shown, the swirl burner on the leftmost side of the front water-cooled wall 33 is the swirl burner 39. The swirl burner on the leftmost side of the rear water-cooled wall 35 is the swirl burner 39. The swirl burner 39 on the leftmost side of the front water-cooled wall 33 and the rear water-cooled wall 35 constitutes a combustion unit.

[0040] In this embodiment, at least one combustion unit corresponds to at least one side water-cooled wall 37. The correspondence may be that the number of the combustion units is equal to the number of the side water-cooled walls 37. The correspondence may also be that the position of the combustion unit is close to the position of the side water-cooled wall 37. For example, Figure 1 As shown, the furnace 49 includes a side water-cooled wall 37 on the left and a water-cooled wall on the right. That is, the furnace 49 includes two side water-cooled walls 37. The combustion unit includes a combustion unit on the left and a combustion unit on the right. That is, there are two combustion units. The combustion unit on the left is close to the side water-cooled wall 37 on the left. The combustion unit on the right is close to the side water-cooled wall 37 on the right.

[0041] Further, the third air ducts 17 of the two swirl burners 39 are both open toward the corresponding side water-cooled wall 37, so that the airflow in the third air duct 17 can flow toward the corresponding side water-cooled wall 37. That is, the third air duct 17 of the swirl burner 39 of the left combustion unit is open toward the side water-cooled wall 37 on the left, so that the airflow in the third air duct 17 can flow toward the side water-cooled wall 37 on the left. The third air duct 17 of the swirl burner 39 of the right combustion unit is open toward the side water-cooled wall 37 on the right, so that the airflow in the third air duct 17 can flow toward the side water-cooled wall 37 on the right. In this way, the rigidity of the secondary air is effectively increased by the asymmetric peripheral wind of the swirl burner 39, and the left combustion unit improves the reducing atmosphere of the side water-cooled wall 37 area on the left side of the furnace 49, avoiding the problem of poor rigidity of the wall-adhering wind and easy wear; the right combustion unit improves the reducing atmosphere of the side water-cooled wall 37 area on the right side of the furnace 49, avoiding the problem of poor rigidity of the wall-adhering wind and easy wear.

[0042] Further, the swirl combustion system described in the embodiment of the present application also includes: at least one swirl combustion device 41. The at least one may be 1, 2, 3, 4, etc. The swirl combustion device 41 is arranged on the front water-cooled wall 33 and / or the rear water-cooled wall 35. The swirl combustion device 41 is used to inject primary air into the furnace 49. Specifically, the swirl combustion device 41 includes a first air duct 11. The first air duct 11 has an inlet 12 and an outlet 13. The first air duct 11 is used to input primary air into the furnace 49. The primary air is the air sent into the furnace 49 together with the pulverized coal when the pulverized coal is burned. The main function of the primary air is to provide air according to the oxygen required by the pulverized coal during the combustion process in the furnace 49 for the combustion of the furnace 49, and it also has the function of cooling the grate. Specifically, the first air duct 11 is the first air duct 11. The first air duct 11 has an angle of not 0 degrees or 180 degrees with the surface of the front water-cooled wall 33 or the rear water-cooled wall 35. Preferably, the angle between the first air duct 11 and the surface of the front water-cooled wall 33 or the rear water-cooled wall 35 is 90 degrees. That is, the first air duct 11 is arranged perpendicularly to the surface of the front water-cooled wall 33 or the rear water-cooled wall 35. Specifically, an opening is arranged on the front water-cooled wall 33 or the rear water-cooled wall 35. The first air duct 11 is penetrated in the opening. Further, a first air duct 21 for primary air circulation is formed in the first air duct 11. Further, the first air duct 11 has an inlet 12 and an outlet 13. Specifically, the inlet 12 and the outlet 13 are respectively arranged at both ends of the first air duct 21. Further, the outlet 13 is open toward the combustion chamber 43 so that the primary air energy can be input into the combustion chamber 43 through the outlet 13. Further, the swirl combustion device 41 also includes a second air duct 14. The first air duct 11 is penetrated in the second air duct 14. An annular space is formed between the second air duct 14 and the first air duct 11. The annular space is used to input secondary air into the furnace 49. The secondary air is used to provide oxygen for the pulverized coal.

[0043] Furthermore, the swirl combustion device 41 is arranged on a side of the swirl burner 39 away from the side water-cooled wall 37. Figure 5 As shown, the swirl combustion device 41 is arranged on the right side of the swirl burner 39 on the left side. And the swirl combustion device 41 is arranged on the left side of the swirl burner 39 on the right side. That is, the two first swirlers on the front water-cooled wall 33 are located on the outside of the second swirl. The two first swirlers on the rear water-cooled wall 35 are located on the outside of the second swirl. In this way, the high-temperature corrosion phenomenon of the side water-cooled wall 37 can be alleviated by the asymmetric peripheral wind of the first swirl.

[0044] Furthermore, a multi-layer swirl combustion system is provided on the front water-cooled wall 33. A multi-layer swirl combustion system is provided on the rear water-cooled wall 35. For example, Figure 1 As shown, an upper swirl combustion system, a middle swirl combustion system and a lower swirl combustion system are arranged on the front water-cooled wall 33. The upper swirl combustion system, the middle swirl combustion system and the lower swirl combustion system each include two combustion units and a plurality of swirl combustion devices 41 located between the two combustion units. Furthermore, since the flow in the third air duct 17 is a direct current asymmetric peripheral wind, the jet is ejected at a certain angle to the side water-cooled wall 37 on the left and the side water-cooled wall 37 on the right, with a long range and strong rigidity, so that a gas barrier can be formed between the side water-cooled wall 37 on the left and the side water-cooled wall 37 on the right, reducing the accumulation of reducing gas generated by combustion in the side water-cooled wall 37 and the side water-cooled wall 37 area, thereby alleviating the high-temperature corrosion phenomenon of the side water-cooled wall 37 of the furnace 49.

[0045] Furthermore, the third air duct 17 of the swirl burner 39 has an angle with the axial direction of the first air duct 11. That is, the asymmetric peripheral winds of the front water-cooled wall 33 and the rear water-cooled wall 35 are mirror-symmetrical. In this way, the airflows in the third air ducts 17 of the two swirl burners 39 can converge when they do not contact the side water-cooled wall 37. That is, the asymmetric peripheral winds in the second air duct 14 of the swirl burner 39 blow toward the side water-cooled wall 37 at a certain angle, so that the mirror-symmetrical peripheral winds on both sides converge before reaching the side water-cooled wall 37, which not only effectively increases the oxygen content in the area of ​​the side water-cooled wall 37 and suppresses the formation of a reducing atmosphere, but also avoids the scouring and wear of the side water-cooled wall 37 by the asymmetric peripheral wind.

[0046] Furthermore, the application method of the swirl combustion system of the embodiment of the present application is as follows:

[0047] First, as shown in the figure, the asymmetric peripheral wind tubes of the swirl burners 39 close to the side water-cooled wall 37 on the left side of the furnace 49 and the side water-cooled wall 37 on the right side are placed close to the side water-cooled wall 37.

[0048] Then, the coal powder delivery rate of the first air duct 11 in the swirl burner 39 close to the left side water-cooled wall 37 and the right side water-cooled wall 37 is appropriately reduced to reduce the reducing gas that can be generated by the swirl burner 39 during the combustion process.

[0049] Next, the baffle 31 in the drainage pipe 29 is adjusted so that the flow rate and flow rate of the gas in the second air duct 19 and the third air duct 17 can be reasonably distributed.

[0050] Finally, the gas diverted to the third air duct 17 has strong rigidity after passing through the third air duct 17, forming a gas barrier that can effectively inhibit the diffusion of the reducing swirl gas generated by combustion to the left side water-cooled wall 37 and the right side water-cooled wall 37, thereby reducing the adverse effects of the reducing gas generated by combustion of the swirl burner 39 on the left side water-cooled wall 37 and the right side water-cooled wall 37. At the same time, the asymmetric peripheral wind is located outside the flame, which can also provide oxygen for combustion, making the combustion more complete.

[0051] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, and they cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0052] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the foregoing claims and the full scope of equivalents to which such claims are entitled. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to be a waiver of such subject matter, nor should it be considered that the applicant has not considered such subject matter to be part of the disclosed application subject matter.

Claims

1. A swirl burner that can effectively inhibit high-temperature corrosion of the boiler furnace side wall, characterized in that: include: A first air duct having an inlet and an outlet for inputting primary air into the furnace; a second air duct, the second air duct being sleeved outside the first air duct; An annular space is formed between the second air duct and the first air duct; a partition, which is arranged in the annular space, and the partition divides the annular space into a third air duct away from the first air duct and a second air duct located between the first air duct and the third air duct; the second air duct is used to input secondary air into the furnace; the cross-sectional area of ​​the third air duct gradually decreases from the inlet to the outlet to form a nozzle; One end of the third air duct close to the inlet is annular; one end of the third air duct close to the outlet is semi-annular; A cross section of the third air duct along the axial direction extends outwardly in a direction from the inlet to the outlet.

2. The swirl burner capable of effectively inhibiting high temperature corrosion of the boiler furnace side wall according to claim 1 is characterized in that: The partition is a tube body, and the tube body is sleeved outside the first air duct; the second air duct is sleeved outside the tube body.

3. The swirl burner capable of effectively inhibiting high temperature corrosion of the boiler furnace side wall according to claim 1 is characterized in that: The included angle between the axial direction of the third air duct and the first air duct is 6 degrees to 12 degrees.

4. The swirl burner capable of effectively inhibiting high temperature corrosion of the boiler furnace side wall according to claim 1 is characterized in that: One end of the second air duct close to the inlet is connected with a drainage pipe; the drainage pipe is in communication with the annular space; and is used to input secondary air into the third air duct and the second air duct.

5. The swirl burner capable of effectively inhibiting high temperature corrosion of the boiler furnace side wall according to claim 4 is characterized in that: The drainage pipe is provided with a baffle for adjusting the airflow in the third air duct and the second air duct.

6. A swirl combustion system for a furnace, the furnace comprising a front water-cooled wall, a rear water-cooled wall and at least one side water-cooled wall located between the front water-cooled wall and the rear water-cooled wall; characterized in that: The swirl combustion system comprises: At least one combustion unit; corresponding to at least one of the side water-cooled walls; the combustion unit includes two swirl burners as described in any one of claims 1 to 5 that can effectively inhibit high-temperature corrosion of the boiler furnace side wall; the two swirl burners are respectively arranged on the front water-cooled wall and the rear water-cooled wall; and the third air ducts of the two swirl burners are open toward the corresponding side water-cooled wall, so that the airflow in the third air duct can flow toward the corresponding side water-cooled wall.

7. The swirl combustion system according to claim 6, characterized in that: Also includes: At least one swirl combustion device; arranged on the front water-cooled wall and / or the rear water-cooled wall; the swirl combustion device includes a first air duct, having an inlet and an outlet, for inputting primary air into the furnace; the swirl combustion device is arranged on the side of the swirl burner away from the side water-cooled wall.

8. The swirl combustion system according to claim 6, characterized in that: An included angle is formed between the third air duct of the swirl burner and the axial direction of the first air duct, so that the airflows in the third air ducts of the two swirl burners can converge when they do not contact the side water-cooled wall.

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