Secondary air system of circulating fluidized bed boiler co-burning solid waste and control method

Abstract

The invention discloses a secondary air system of a circulating fluidized bed boiler co-burning solid waste and a control method, and belongs to the technical field of circulating fluidized bed boilers. A first detection assembly is fixedly installed on a secondary fan and an air pre-heater jointly, a secondary air pipeline is arranged in an inner ring of the first detection assembly, a secondary air box is fixedly arranged on a fluidized bed boiler, a second detection assembly is fixedly installed on the air pre-heater and the secondary air box jointly, and the secondary air pipeline is arranged in an inner ring of the second detection assembly. A plurality of secondary air nozzles are arranged on the fluidized bed boiler in a communicating mode, opening and closing assemblies are rotationally arranged on the secondary air nozzles, and cleaning assemblies are further fixedly arranged on the secondary air nozzles. And the secondary air nozzle can be cleaned through wind power, and electric energy is saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of circulating fluidized bed boilers, and in particular, relates to a secondary air system and a control method for a circulating fluidized bed boiler for burning solid waste. Background Art

[0002] A circulating fluidized bed boiler is a boiler that uses fluidized combustion technology. It is widely used in the power generation and industrial fields. In order to practice the concept of environmental protection, in addition to using pure fuel for combustion, circulating fluidized bed boilers can also mix fuel with biomass fuels such as sludge for combustion during use. This not only recycles solid waste, but also reduces fuel usage.

[0003] Chinese patent CN217329769U announces a circulating fluidized bed boiler secondary air classification arrangement system, including a circulating fluidized bed boiler body and a secondary fan, wherein the secondary fan is arranged on one side of the circulating fluidized bed boiler body, and a dual-channel air inlet structure is arranged on the side wall of the circulating fluidized bed boiler body, wherein the dual-channel air inlet structure adopts a layered structure design and is connected to the secondary fan, and the utility model adopts a dual-channel layered structure design, and the air outlet is arranged in a circular array, and the air volume on each branch can be adjusted, thereby effectively improving the stability of secondary air injection, and at the same time cooperating with the wind direction adjustment structure, the injected secondary air is effectively adjusted, the structure is reasonable, the operation is simple, and the practicability is strong.

[0004] The prior art announced above proposes a secondary air classification arrangement system for a circulating fluidized bed boiler. Although the secondary air classification arrangement system can adjust the amount and direction of the secondary air entering, the secondary air classification arrangement system does not have the function of detecting the secondary air duct. Therefore, when the secondary air duct leaks, the amount of secondary air entering will be unstable, which will affect the combustion effect of the circulating fluidized bed boiler. In addition, after a long period of use, dust will accumulate inside the secondary air nozzle in the secondary air system, which will cause the inner diameter of the secondary air nozzle to change, and then the secondary air will change its path when passing through the secondary air nozzle, which will eventually make the secondary air entering the furnace unstable, which will also affect the combustion effect.

[0005] Therefore, we proposed a secondary air system and control method for a circulating fluidized bed boiler that burns solid waste in order to solve the above-mentioned problems. Summary of the invention

[0006] In view of the problem that the prior art lacks the function of detecting the secondary air duct, and that after a long period of use, dust will accumulate inside the secondary air nozzles in the secondary air system, affecting the combustion effect, the purpose of the present invention is to provide a secondary air system and control method for a circulating fluidized bed boiler for co-firing solid waste.

[0007] In order to solve the above problems, the technical solution adopted by the present invention is as follows: a secondary air system for a circulating fluidized bed boiler for co-burning solid waste, comprising a fluidized bed boiler, a secondary fan and an air preheater are respectively arranged on the sides of the fluidized bed boiler, the secondary fan and the air preheater are connected through a secondary air duct, a detection component one is fixedly installed on the secondary fan and the air preheater, and the secondary air duct is arranged in the inner circle of the detection component one, a secondary air box is fixedly installed on the fluidized bed boiler, the air preheater and the secondary air box are connected through the secondary air duct, a detection component two is fixedly installed on the air preheater and the secondary air box, and the secondary air duct is arranged in the inner circle of the detection component two, a plurality of secondary air nozzles are connected on the fluidized bed boiler, the air inlet end of the secondary air nozzle and the air outlet end of the secondary air box are connected through the secondary air duct, an opening and closing component is rotatably arranged on the secondary air nozzle, and a cleaning component is also fixedly arranged on the secondary air nozzle.

[0008] Furthermore, the detection component 1 includes a transparent shell 1, an electronic air valve is connected to the top surface of the transparent shell 1, a color film is tightly bonded to the circumferential outer wall of the secondary air duct, and an air cavity is formed between the circumferential outer wall of the color film and the side wall of the inner cavity of the transparent shell 1.

[0009] Furthermore, the secondary air box comprises an annular box body, and the inner side wall of the annular box body is fixedly connected to the outer side wall of the fluidized bed boiler via a plurality of connecting blocks.

[0010] Furthermore, the detection component 2 includes a transparent shell 2, a square tube is arranged in the inner cavity of the transparent shell 2, the outer wall of the square tube is fixedly connected to the inner wall of the transparent shell 2 by a plurality of fixing blocks, four mounting plates are fixedly installed on the inner wall of the transparent shell 2, the four mounting plates are respectively arranged parallel to the four side walls of the square tube, a plurality of through holes are opened on each mounting plate, a film is arranged on the side wall of the inner cavity of the through hole, white paint is coated on the side wall of the film facing the transparent shell 2, and brightly colored paint is coated on the side wall of the film facing the square tube, a plurality of lifting components are fixedly installed on the outer wall of the square tube, and the lifting components are concentrically arranged with the through holes and the film.

[0011] Furthermore, the square tube includes a tube body, and guide plates are fixedly installed at four corners inside the tube body.

[0012] Furthermore, the lifting assembly includes a mounting cylinder fixedly mounted on the outer wall of the tube body and a push block slidably mounted inside the mounting cylinder. The push block and the mounting cylinder are elastically connected by a first spring. An air chamber is also formed between the push block and the mounting cylinder. The air chamber contains an inert gas. A plurality of mounting grooves are provided at the edge of the outer wall of the push block. A limiting column is fixedly mounted in the inner cavity of the mounting groove. A push rod is rotatably sleeved on the limiting column. The side wall of the push rod is elastically connected to the side wall of the inner cavity of the mounting groove by a second spring.

[0013] Furthermore, the secondary air nozzle comprises a nozzle body, a side wall of the nozzle body is provided with a through groove, and a baffle is fixedly mounted on the inner side wall of the through groove.

[0014] Furthermore, the opening and closing assembly includes an F-shaped bracket fixedly mounted on the side wall of the nozzle body and a motor fixedly mounted on the F-shaped bracket, the output end of the motor is fixedly connected to a rotating shaft, the rotating shaft is penetrated in the through groove, a flip plate is rotatably arranged in the through groove, the flip plate is fixedly sleeved on the rotating shaft, an embedded portion is opened on the inner side wall of the flip plate, the shapes of the embedded portion and the baffle are mutually embedded, a high temperature resistant sealing gasket is arranged at the contact position between the embedded portion and the baffle, and a sealing plate is embedded and slidably installed on the side wall of the through groove cavity.

[0015] Further, the cleaning assembly includes a first load-bearing plate fixedly mounted on the side wall of the nozzle body and a second load-bearing plate fixedly mounted on the first load-bearing plate, a pair of electric telescopic columns are fixedly mounted on the side wall of the second load-bearing plate, a connecting plate is fixedly mounted on the output ends of the two electric telescopic columns, a pair of mounting frames are fixedly mounted on the outer side wall of the connecting plate, a connecting shaft is rotatably mounted on the mounting frame, a fan blade is fixedly mounted on the side wall at one end of the connecting shaft, and a first cleaning member, a second cleaning member and a third cleaning member are fixedly connected to the outer side wall of the connecting shaft respectively; The first cleaning member comprises a first connecting rod fixedly connected to the outer wall of the connecting shaft, a first slide groove is provided inside the first connecting rod, an inert gas is contained inside the first slide groove, a first scraper is slidably installed inside the first slide groove, and the first scraper is elastically connected to the side wall of the inner cavity of the first slide groove through a third spring; The second cleaning member comprises a second connecting rod fixedly connected to the outer wall of the connecting shaft, and second sliding grooves are respectively provided at both ends of the second connecting rod, and the interior of the second sliding groove contains inert gas, and a second scraper is slidably installed inside the second sliding groove, and the second scraper is elastically connected to the side wall of the inner cavity of the second sliding groove through a fourth spring; The third cleaning member includes a third connecting rod fixedly connected to the outer wall of the connecting shaft, a third slide groove is provided inside the third connecting rod, an inert gas is contained inside the third slide groove, a third scraper is slidably installed inside the third slide groove, and the third scraper is elastically connected to the side wall of the inner cavity of the third slide groove through a fifth spring.

[0016] The present invention also provides another technical solution: a control method for a secondary air system of a circulating fluidized bed boiler for solid waste combustion, comprising the following steps: S: When the inspection staff observes through the transparent shell to see if there are bubbles in the color film, it is used to determine whether there is a leak in the secondary air duct; S: The inspector observes through the transparent shell 2 to see if the film has a bright color, which is used to determine whether the secondary air duct is damaged; S: After running for a period of time, the fluidized bed boiler stops running and the cleaning component is started to clean the dust inside the secondary air nozzle; S: After the dust cleaning is completed, the cleaning components are reset and the fluidized bed boiler starts running.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. When the inspection staff observes bubbles in the color film through the transparent shell, it means that a large leakage has occurred in the secondary air duct, and corresponding countermeasures can be taken to stop the loss in time. Moreover, due to the setting of the transparent shell, the leaked high-pressure gas will not be blown directly to the outside, reducing the probability of causing other accidents.

[0018] 2. Inspection personnel can easily see the broken brightly colored film through the transparent shell 2, and then immediately determine that this section of the secondary air duct is damaged. The operator can immediately take remedial measures to reduce the loss and take corresponding measures to ensure the full combustion of the fuel. The setting of the transparent shell 2 can prevent high-temperature gas from being directly sprayed to the outside, reducing the risk of damage to surrounding equipment and personnel.

[0019] 3. The cleaning component used in the present invention has a high degree of automation, and the secondary air nozzle can be cleaned by wind power, saving electricity. There is no need to wait for the fluidized bed boiler to drop to a very low temperature before operation, saving time cost, and no personnel need to use tools for cleaning. It is not only efficient, but also will not cause physical harm to the operator. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 A magnified image of point A; Figure 3 is a cross-sectional schematic diagram of a detection component 1 of the present invention; Figure 4 for Figure 3 The enlarged view of point B; Figure 5It is a disassembly schematic diagram of the detection component 1 of the present invention; Figure 6 It is a cross-sectional schematic diagram of the secondary air box and the second detection assembly of the present invention; Figure 7 for Figure 6 Enlarged view of point C; Figure 8 It is a schematic diagram of the installation position of the detection component 2 of the present invention; Fig. 9 for Figure 8 The enlarged view of point D; Fig.10 It is a three-dimensional structural schematic diagram of the jacking assembly of the present invention; Fig.11 is a cross-sectional schematic diagram of the jacking assembly of the present invention; Fig.12 It is a schematic diagram of the installation position of the secondary air nozzle of the present invention; Fig.13 for Fig.12 The enlarged view of point E; Fig.14 It is a schematic diagram of the opening state of the opening and closing component of the present invention; Fig.15 It is a disassembly schematic diagram of the opening and closing assembly of the present invention; Fig.16 It is a schematic diagram of the installation position of the baffle of the present invention; Fig.17 is a cross-sectional schematic diagram of the secondary air nozzle of the present invention; Fig.18 for Fig.17 The enlarged view of F; Fig.19 It is a cross-sectional schematic diagram of the first cleaning member, the second cleaning member and the third cleaning member of the present invention; Fig. 20 for Fig.19 The enlarged view of G; Fig.21 for Fig.19 Enlarged view of H; Fig. 22 It is a three-dimensional structural schematic diagram of the cleaning component of the present invention; Fig.23 for Fig.23 Enlarged view of point I.

[0021] In the figure: 1, fluidized bed boiler; 2, secondary fan; 3, air preheater; 4, detection component one; 41, transparent shell one; 42, color film; 43, electronic gas valve; 44, air cavity; 5, secondary air box; 51, annular box; 52, connecting block; 6, detection component two; 61, transparent shell two; 62, square tube; 621, tube body; 622, guide plate; 63, fixing block; 64, mounting plate; 65, through hole; 66, lifting component; 661, mounting cylinder; 662, push block; 663, air chamber; 664, first spring; 665, mounting groove; 666, limit column; 667, ejector rod; 668, second spring; 67, film; 7, secondary air nozzle; 71, nozzle body; 72, through groove; 73, baffle; 74, high temperature resistant sealing pad; 8, cleaning management component; 81, the first load-bearing plate; 82, the second load-bearing plate; 83, the electric telescopic column; 84, the connecting plate; 85, the mounting frame; 86, the connecting shaft; 87, the fan blade; 88, the first cleaning piece; 881, the first connecting rod; 882, the first slide groove; 883, the first scraper; 884, the third spring; 89, the second cleaning piece; 891, the second connecting rod; 892, the second slide groove; 893, the second scraper; 894, the fourth spring; 820, the third cleaning piece; 8201, the third connecting rod; 8202, the third slide groove; 8203, the third scraper; 8204, the fifth spring; 9, the secondary air duct; 10, the opening and closing component; 101, the F-shaped bracket; 102, the motor; 103, the rotating shaft; 104, the flip plate; 105, the embedded part; 106, the blocking plate. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with specific embodiments.

[0023] In order to solve the problem that the existing secondary air system cannot detect air leakage in the secondary air duct 9 between the secondary fan 2 and the air preheater 3, Figure 1 - Figure 6 As shown: A secondary air system for a circulating fluidized bed boiler for burning solid waste comprises a fluidized bed boiler 1. After pure fuel and biomass fuel are mixed, the mixed fuel is transported to the furnace of the fluidized bed boiler 1 through a feed port for combustion. A secondary air fan 2 and an air preheater 3 are respectively arranged on the sides of the fluidized bed boiler 1. The secondary air fan 2 and the air preheater 3 are connected through a secondary air duct 9. The secondary air fan 2 is used to generate secondary air, and the air preheater 3 is used to heat the secondary air to prevent the oxygen supply from being affected by frost on the secondary air duct 9. The heated secondary air enters the furnace, which is beneficial to the full combustion of the fuel. A detection component 4 is fixedly installed on the secondary air fan 2 and the air preheater 3, and the secondary air duct 9 is arranged on the detection component 1. 4, the detection component 1 4 is used to detect whether the secondary air duct 9 between the secondary fan 2 and the air preheater 3 is leaking, so as to keep the secondary air system in a stable operating state at all times. A secondary air box 5 is fixedly arranged on the fluidized bed boiler 1, and the air preheater 3 and the secondary air box 5 are connected by the secondary air duct 9. The gas heated by the air preheater 3 will enter the secondary air box 5 through the secondary air duct 9. A detection component 2 6 is fixedly installed on the air preheater 3 and the secondary air box 5, and the secondary air duct 9 is arranged in the inner circle of the detection component 2 6. The detection component 2 6 is used to detect whether the secondary air duct 9 between the air preheater 3 and the secondary air box 5 is leaking, also to keep the secondary air system in a stable operating state at all times.

[0024] A plurality of secondary air nozzles 7 are connected to the fluidized bed boiler 1. The air inlet end of the secondary air nozzle 7 is connected to the air outlet end of the secondary air box 5 via a secondary air duct 9. The secondary air in the secondary air box 5 enters the secondary air nozzle 7 through the secondary air duct 9, and is then sprayed into the furnace of the fluidized bed boiler 1 by the secondary air nozzle 7 to promote the complete combustion of the fuel. An opening and closing component 10 is rotatably provided on the secondary air nozzle 7. A cleaning component 8 is also fixedly provided on the secondary air nozzle 7. When dust is accumulated inside the secondary air nozzle 7, the opening and closing component 10 is started to connect the inside of the secondary air nozzle 7 with the outside world, and then the dust accumulated inside the secondary air nozzle 7 is cleaned by the cleaning component 8. After the dust is cleaned, the opening and closing component 10 is started again to disconnect the inside of the secondary air nozzle 7 from the outside world, and then the secondary air nozzle 7 can be used normally.

[0025] The detection component 4 includes a transparent shell 41, on the top surface of which an electronic air valve 43 is connected, a color film 42 is tightly bonded to the circumferential outer wall of the secondary air duct 9, and an air cavity 44 is formed between the circumferential outer wall of the color film 42 and the side wall of the inner cavity of the transparent shell 41.

[0026] Specifically, since the secondary air has not yet been heated by the air preheater 3, the temperature of this section of the secondary air duct 9 is relatively low. In the initial state, the operator uses an external air pump to inflate the air cavity 44 through the electronic air valve 43, so that a suitable air pressure is generated inside the air cavity 44. The high-pressure gas in the air cavity 44 will generate pressure on the color film 42, so that the color film 42 is firmly attached to the circumferential outer wall of the secondary air duct 9 to prevent the color film 42 from falling off. When a small leak occurs in the secondary air duct 9 and the secondary air speed is small, the sealing effect of the color film 42 and the pressure of the high-pressure gas in the air cavity 44 can achieve the effect of initially blocking the leak, so that the air volume of the secondary air is controlled. In a stable state, the influence on the internal combustion effect of the fluidized bed boiler 1 is reduced. When a large leakage occurs in the secondary air duct 9 and the secondary air speed is large, the air flow pressure blown out from the damaged part of the secondary air duct 9 is greater than the pressure of the high-pressure gas in the air cavity 44, resulting in the formation of bubbles on the circumferential outer wall of the secondary air duct 9 by the colored film 42. When the inspection staff observes bubbles in the colored film 42 through the transparent shell 41, it means that a large leakage has occurred in the secondary air duct 9, and corresponding countermeasures can be taken to stop the loss in time. Moreover, since a transparent shell 41 is provided, the leaked high-pressure gas will not be directly blown to the outside, thereby reducing the probability of causing other accidents.

[0027] In order to solve the problem that the existing secondary air system cannot detect air leakage in the secondary air duct 9 between the air preheater 3 and the secondary air box 5, Figure 1 - Figure 2 and Figure 6 - Fig.11 As shown: The secondary air box 5 comprises an annular box body 51 , and the inner side wall of the annular box body 51 is fixedly connected to the outer side wall of the fluidized bed boiler 1 via a plurality of connecting blocks 52 .

[0028] The detection component 2 6 includes a transparent shell 2 61. The setting of the transparent shell 2 61 is convenient for the inspection personnel to observe the internal conditions through the transparent shell 2 61. A square tube 62 is arranged in the inner cavity of the transparent shell 2 61. The square tube 62 is made of heat-conducting material. The outer wall of the square tube 62 is fixedly connected to the inner wall of the transparent shell 2 61 through a plurality of fixing blocks 63. Four mounting plates 64 are fixedly installed on the inner wall of the transparent shell 2 61. The four mounting plates 64 are respectively arranged in parallel with the four side walls of the square tube 62. Each mounting plate 64 is provided with a plurality of through holes 65. A film 67 is arranged on the side wall of the inner cavity of the through hole 65. The side wall of the film 67 facing the transparent shell 2 61 is coated with white paint, and the side wall of the film 67 facing the square tube 62 is coated with brightly colored paint. A plurality of lifting components 66 are fixedly installed on the outer wall of the square tube 62. The lifting components 66 are concentrically arranged with the through holes 65 and the film 67.

[0029] The square tube 62 includes a tube body 621 , and guide plates 622 are fixedly installed at the four corners inside the tube body 621 . When the damaged part of the secondary air duct 9 faces the guide plates 622 , the high-temperature airflow ejected from the secondary air duct 9 will diverge to both sides through the guide plates 622 .

[0030] The lifting assembly 66 includes a mounting tube 661 fixedly mounted on the outer wall of the tube body 621 and a push block 662 slidably mounted inside the mounting tube 661. The push block 662 and the mounting tube 661 are elastically connected via a first spring 664. An air chamber 663 is also formed between the push block 662 and the mounting tube 661. The air chamber 663 is filled with an inert gas. A plurality of mounting grooves 665 are provided at the edge of the outer wall of the push block 662. A limiting column 666 is fixedly mounted in the inner cavity of the mounting groove 665. A push rod 667 is rotatably sleeved on the limiting column 666. The side wall of the push rod 667 is elastically connected to the side wall of the inner cavity of the mounting groove 665 via a second spring 668.

[0031] Specifically, since the secondary air has been heated by the air preheater 3 at this time, the secondary air in this section of the secondary air duct 9 has a relatively high temperature. When the circumferential outer wall of the secondary air duct 9 is damaged, the high-temperature gas inside the secondary air duct 9 will be quickly sprayed onto the square tube 62. Since the square tube 62 is made of heat-conducting material, the square tube 62 will quickly conduct the temperature to the inside of the air chamber 663 and heat the inert gas inside the air chamber 663. The heated inert gas expands and generates thrust. When the thrust is greater than the elastic force of the first spring 664, the push block 662, the limit column 666 and the push rod 667 are pushed together to move toward the outside of the mounting tube 661. During the process, the push rod 667 will poke the film 67 in the through hole 65 outwards. When the push rod 667 approaches the end of the mounting tube 661 and passes over the edge of the opening of the mounting tube 661, under the elastic force of the second spring 668, the push rod 667 will flip outwards to expand the damaged part of the film 67 and flip the side of the film 67 coated with colored paint to the side facing the transparent shell 61, so that the inspection personnel can easily see the broken and brightly colored film 67 through the transparent shell 61, and then immediately determine that this section of the secondary air duct 9 is damaged, and the operator can immediately take remedial measures to reduce the loss and take corresponding measures to ensure the full combustion of the fuel.

[0032] When the damaged part of the secondary air duct 9 is facing the guide plate 622, the high-temperature airflow ejected from the inside of the secondary air duct 9 will radiate to both sides through the guide plate 622, and the square tube 62 will continue to transfer the heat to the nearby lifting assembly 66, so that the lifting assembly 66 will break the film 67, so that the inspection personnel can find that this section of the secondary air duct 9 is damaged, and prevent the existence of dead corners, which will cause the lifting assembly 66 to be unable to break the film 67, and the inspection personnel will be unable to find the damage of the secondary air duct 9 in time, which will eventually not only affect the combustion effect of the fuel, but may also cause other accidents. The setting of the transparent shell 61 can prevent the high-temperature gas from being directly sprayed to the outside, reducing the risk of damage to surrounding equipment and personnel.

[0033] Since the secondary air temperature in this section is relatively high, when the secondary air duct 9 is not damaged, the secondary air duct 9 will also conduct a small portion of the heat to the air chamber 663 through the square tube 62. At this time, the air pressure generated by the inert gas in the air chamber 663 cannot overcome the elastic force of the first spring 664. Therefore, the lifting component 66 will pierce the film 67, which will not cause the inspection personnel to misjudge.

[0034] When the damaged part of the secondary air duct 9 is repaired, the temperature in the air chamber 663 decreases, so that the pressure of the inert gas is less than the elastic force of the first spring 664. At this time, the lifting assembly 66 gradually retracts toward the inside of the mounting tube 661. During this process, the outer wall of the push rod 667 will contact the inner wall of the mounting tube 661, and the push rod 667 will flip toward the inside of the mounting groove 665 and compress the second spring 668. Through this setting, several push rods 667 are restored to a gathered state for the next use. Then the maintenance personnel can replace the broken film 67 with a new film 67 for the next inspection. The setting method is simple and convenient for maintenance and easy to observe.

[0035] In order to solve the problem that dust is accumulated inside the secondary air nozzle 7 after long-term use, thereby affecting the combustion effect, Fig.12 - Fig.23 As shown: The secondary air nozzle 7 comprises a nozzle body 71 . A through slot 72 is formed on a side wall of the nozzle body 71 . A baffle 73 is fixedly mounted on an inner side wall of the through slot 72 .

[0036] The opening and closing assembly 10 includes an F-shaped bracket 101 fixedly mounted on the side wall of the nozzle body 71 and a motor 102 fixedly mounted on the F-shaped bracket 101. The output end of the motor 102 is fixedly connected to a rotating shaft 103. The rotating shaft 103 is penetrated and arranged in the through groove 72. A flip plate 104 is rotatably arranged in the through groove 72. The flip plate 104 is fixedly sleeved on the rotating shaft 103. An embedded portion 105 is opened on the inner side wall of the flip plate 104. The shapes of the embedded portion 105 and the baffle 73 are mutually embedded. A high temperature resistant sealing gasket 74 is arranged at the contact position between the embedded portion 105 and the baffle 73. A sealing plate 106 is embedded and slidably installed on the side wall of the inner cavity of the through groove 72.

[0037] The cleaning assembly 8 includes a first load-bearing plate 81 fixedly mounted on the side wall of the nozzle body 71 and a second load-bearing plate 82 fixedly mounted on the first load-bearing plate 81, a pair of electric telescopic columns 83 are fixedly mounted on the side wall of the second load-bearing plate 82, a connecting plate 84 is fixedly mounted on the output ends of the two electric telescopic columns 83, a pair of mounting frames 85 are fixedly mounted on the outer side wall of the connecting plate 84, a connecting shaft 86 is rotatably mounted through the mounting frames 85, a fan blade 87 is fixedly mounted on the side wall of one end of the connecting shaft 86, and a first cleaning member 88, a second cleaning member 89 and a third cleaning member 820 are fixedly connected to the outer side walls of the connecting shaft 86, respectively.

[0038] The first cleaning member 88 includes a first connecting rod 881 fixedly connected to the outer wall of the connecting shaft 86, a first slide groove 882 is provided inside the first connecting rod 881, an inert gas is contained inside the first slide groove 882, a first scraper 883 is slidably installed inside the first slide groove 882, and the first scraper 883 is elastically connected to the side wall of the inner cavity of the first slide groove 882 by a third spring 884.

[0039] The second cleaning member 89 includes a second connecting rod 891 fixedly connected to the outer wall of the connecting shaft 86, and second slide grooves 892 are respectively provided at both ends of the second connecting rod 891. The interior of the second slide groove 892 is filled with inert gas, and a second scraper 893 is slidably installed inside the second slide groove 892. The second scraper 893 is elastically connected to the side wall of the inner cavity of the second slide groove 892 through a fourth spring 894.

[0040] The third cleaning component 820 includes a third connecting rod 8201 fixedly connected to the outer wall of the connecting shaft 86, the third connecting rod 8201 is provided with a third slide groove 8202, the third slide groove 8202 is filled with inert gas, the third scraper 8203 is slidably installed inside the third slide groove 8202, and the third scraper 8203 is elastically connected to the side wall of the inner cavity of the third slide groove 8202 through a fifth spring 8204.

[0041] Specifically, after the secondary air nozzle 7 has been used for a long time, a lot of dust will be accumulated inside the secondary air nozzle 7. When cleaning the dust inside the secondary air nozzle 7, usually, the fluidized bed boiler 1 is stopped first, and the fluidized bed boiler 1 is waited to be lowered to a suitable temperature. Only then will the operator wear protective gear and use professional cleaning tools to clean the dust inside the secondary air nozzle 7. This cleaning method is not only inefficient, but also requires waiting for the fluidized bed boiler 1 to be lowered to a suitable temperature before the operation can be started, which is time-consuming and will cause a certain degree of harm to the health of the operator. The specific operation of the present invention is as follows: first, after the fluidized bed boiler 1 is stopped, the operation can be carried out without waiting for the fluidized bed boiler 1 to drop to a very low temperature, thereby saving time cost, and then starting the motor 102, which drives the flip plate 104 to flip outward through the rotating shaft 103, so that the interior of the secondary air nozzle 7 is in a connected state with the outside, and then starting the two electric telescopic columns 83 to extend, driving the connecting plate 84, the mounting frame 85, the connecting shaft 86, the fan blade 87, the first cleaning part 88, the second cleaning part 89 and the third cleaning part 820 to move toward the interior of the secondary air nozzle 7. When they are moved into place, the two electric telescopic columns 83 stop extending. Since the secondary air in this section has a higher temperature, the inert gas inside the first chute 882, the second chute 892 and the third chute 8202 expands due to heat. , push the first scraper 883 out of the first slide groove 882, push the second scraper 893 out of the second slide groove 892, and push the third scraper 8203 out of the third slide groove 8202, so that the first cleaning member 88, the second cleaning member 89 and the third cleaning member 820 can fit the shape of the inside of the secondary air nozzle 7, so as to achieve a better cleaning effect. When cleaning the dust inside the secondary air nozzle 7, increase the wind speed of the secondary air to blow the fan blades 87 to rotate at a high speed. During the high-speed rotation of the fan blades 87, the connecting shaft 86 will be driven to rotate synchronously, and the connecting shaft 86 will then drive the first cleaning member 88, the second cleaning member 89 and the third cleaning member 820 to rotate, so as to achieve the effect of cleaning the dust inside the secondary air nozzle 7. After the cleaning is completed, reset the various components.

[0042] This cleaning method has a high degree of automation, and the secondary air nozzle 7 can be cleaned by wind power, saving electricity. There is no need to wait for the fluidized bed boiler 1 to drop to a very low temperature before operation, saving time costs, and no personnel need to use tools for cleaning. It is not only efficient, but also will not cause physical harm to the operator.

[0043] Since the flip plate 104 is rotatably arranged inside the through groove 72, in order not to interfere with the flipping action of the flip plate 104, the length of the through groove 72 is greater than the length of the flip plate 104. This makes the side wall of the flip plate 104 not tightly fitted with the side wall of the inner cavity of the through groove 72, and air leakage will occur during the secondary air delivery process, which will affect the combustion efficiency of the fuel. In order to alleviate this problem, the present invention provides a baffle 73 on the side wall of the inner cavity of the through groove 72, and opens an embedded portion 105 on the inner side wall of the flip plate 104. The baffle 73 and the embedded portion 105 are interlocked with each other, and a high temperature resistant sealing gasket 74 is provided at the contact portion between the embedded portion 105 and the baffle 73, which completely blocks the gap between the embedded portion 105 and the baffle 73, thereby preventing air leakage and maintaining a stable output of secondary air.

[0044] A blocking plate 106 is slidably installed on the other side wall of the through groove 72. When the flip plate 104 rotates, pressure is applied to the blocking plate 106, causing the blocking plate 106 to retract. When the flip plate 104 passes over the blocking plate 106, the pressure applied to the blocking plate 106 is cancelled, and the blocking plate 106 pops out again and fits tightly with the side wall of the flip plate 104. A sealing gasket may be provided on the side wall of the blocking plate 106. When the blocking plate 106 fits tightly with the side wall of the flip plate 104, a sealing effect is achieved through the sealing gasket, which is also used to maintain a stable output of secondary air to ensure a good combustion effect of the fuel.

[0045] In order to better illustrate the above embodiment, the present invention also provides another implementation scheme: a control method for a secondary air system of a circulating fluidized bed boiler for solid waste combustion, comprising the following steps: Step 1: When the inspection staff observes through the transparent housing 41 whether bubbles appear in the color film 42, it is used to determine whether the secondary air duct 9 is leaking; Step 2: The inspector observes through the transparent housing 61 whether the film 67 has a bright color, so as to judge whether the secondary air duct 9 is damaged; Step 3: After running for a period of time, the fluidized bed boiler 1 stops running, and the cleaning component 8 is started to clean the dust inside the secondary air nozzle 7; Step 4: After the dust cleaning is completed, the cleaning assembly 8 is reset and the fluidized bed boiler 1 starts to operate.

[0046] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0047] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A secondary air system for a circulating fluidized bed boiler for solid waste combustion, comprising a fluidized bed boiler (1), a secondary air fan (2) and an air preheater (3) being arranged on the sides of the fluidized bed boiler (1), the secondary air fan (2) and the air preheater (3) being connected via a secondary air duct (9), characterized in that: The secondary air fan (2) and the air preheater (3) are fixedly mounted with a detection component 1 (4), and a secondary air duct (9) is arranged in the inner circle of the detection component 1 (4). The fluidized bed boiler (1) is fixedly mounted with a secondary air box (5), and the air preheater (3) and the secondary air box (5) are connected via the secondary air duct (9). The air preheater (3) and the secondary air box (5) are fixedly mounted with a detection component 2 (6), and the secondary air duct (9) is arranged in the inner circle of the detection component 2 (6). The fluidized bed boiler (1) is connected with a plurality of secondary air nozzles (7), and the air inlet end of the secondary air nozzle (7) is connected with the air outlet end of the secondary air box (5) via the secondary air duct (9). An opening and closing component (10) is rotatably arranged on the secondary air nozzle (7), and a cleaning component (8) is also fixedly arranged on the secondary air nozzle (7).

2. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 1 is characterized in that: The detection component 1 (4) comprises a transparent shell 1 (41), an electronic air valve (43) is arranged on the top surface of the transparent shell 1 (41), a color film (42) is tightly bonded to the circumferential outer wall of the secondary air duct (9), and an air cavity (44) is formed between the circumferential outer wall of the color film (42) and the side wall of the inner cavity of the transparent shell 1 (41).

3. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 2 is characterized in that: The secondary air box (5) comprises an annular box body (51), and the inner wall of the annular box body (51) is fixedly connected to the outer wall of the fluidized bed boiler (1) via a plurality of connecting blocks (52).

4. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 3 is characterized in that: The detection assembly 2 (6) comprises a transparent shell 2 (61), a square tube (62) is arranged in the inner cavity of the transparent shell 2 (61), the outer wall of the square tube (62) and the inner wall of the transparent shell 2 (61) are fixedly connected via a plurality of fixing blocks (63), four mounting plates (64) are fixedly mounted on the inner wall of the transparent shell 2 (61), the four mounting plates (64) are respectively arranged parallel to the four side walls of the square tube (62), and each mounting plate ( A plurality of through holes (65) are formed on the square tube (64), a film (67) is provided on the side wall of the inner cavity of the through hole (65), a white paint is coated on the side wall of the film (67) facing the transparent shell (61), and a brightly colored paint is coated on the side wall of the film (67) facing the square tube (62), and a plurality of lifting assemblies (66) are fixedly mounted on the outer wall of the square tube (62), and the lifting assemblies (66) are concentrically arranged with the through hole (65) and the film (67).

5. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 4, characterized in that: The square tube (62) comprises a tube body (621), and guide plates (622) are fixedly mounted at four corners inside the tube body (621).

6. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 5, characterized in that: The lifting assembly (66) comprises a mounting tube (661) fixedly mounted on the outer wall of the tube body (621) and a push block (662) slidably mounted inside the mounting tube (661); the push block (662) and the mounting tube (661) are elastically connected via a first spring (664); an air chamber (663) is formed between the push block (662) and the mounting tube (661); an inert gas is contained in the air chamber (663); a plurality of mounting grooves (665) are provided at the edge of the outer wall of the push block (662); a limiting column (666) is fixedly mounted in the inner cavity of the mounting groove (665); a push rod (667) is rotatably sleeved on the limiting column (666); and a side wall of the push rod (667) and a side wall of the inner cavity of the mounting groove (665) are elastically connected via a second spring (668).

7. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 6, characterized in that: The secondary air nozzle (7) comprises a nozzle body (71), a through groove (72) is provided on the side wall of the nozzle body (71), and a baffle (73) is fixedly mounted on the inner side wall of the through groove (72).

8. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 7, characterized in that: The opening and closing assembly (10) comprises an F-shaped bracket (101) fixedly mounted on the side wall of the nozzle body (71) and a motor (102) fixedly mounted on the F-shaped bracket (101); the output end of the motor (102) is fixedly connected to a rotating shaft (103); the rotating shaft (103) is arranged to penetrate the through groove (72); a flip plate (104) is rotatably arranged in the through groove (72); the flip plate (104) is fixedly sleeved on the rotating shaft (103); an embedded portion (105) is provided on the inner side wall of the flip plate (104); the shapes of the embedded portion (105) and the baffle (73) are mutually fitted; a high temperature resistant sealing gasket (74) is provided at the contact portion between the embedded portion (105) and the baffle (73); and a blocking plate (106) is embedded and slidably mounted on the side wall of the inner cavity of the through groove (72).

9. The secondary air system of a circulating fluidized bed boiler for solid waste combustion according to claim 8, characterized in that: The cleaning assembly (8) comprises a first load-bearing plate (81) fixedly mounted on the side wall of the nozzle body (71) and a second load-bearing plate (82) fixedly mounted on the first load-bearing plate (81); a pair of electric telescopic columns (83) are fixedly mounted on the side wall of the second load-bearing plate (82); a connecting plate (84) is fixedly mounted on the output ends of the two electric telescopic columns (83); a pair of mounting frames (85) are fixedly mounted on the outer side wall of the connecting plate (84); a connecting shaft (86) is rotatably mounted through the mounting frame (85); a fan blade (87) is fixedly mounted on the side wall at one end of the connecting shaft (86); and a first cleaning member (88), a second cleaning member (89) and a third cleaning member (820) are respectively fixedly connected to the outer side wall of the connecting shaft (86); The first cleaning member (88) includes a first connecting rod (881) fixedly connected to the outer wall of the connecting shaft (86), a first slide groove (882) is provided inside the first connecting rod (881), an inert gas is contained inside the first slide groove (882), a first scraper (883) is slidably installed inside the first slide groove (882), and the first scraper (883) is elastically connected to the side wall of the inner cavity of the first slide groove (882) via a third spring (884); The second cleaning member (89) comprises a second connecting rod (891) fixedly connected to the outer wall of the connecting shaft (86), and second slide grooves (892) are respectively provided at both ends of the second connecting rod (891), and the interior of the second slide groove (892) contains inert gas, and a second scraper (893) is slidably installed inside the second slide groove (892), and the second scraper (893) is elastically connected to the side wall of the inner cavity of the second slide groove (892) via a fourth spring (894); The third cleaning member (820) comprises a third connecting rod (8201) fixedly connected to the outer wall of the connecting shaft (86); a third sliding groove (8202) is provided inside the third connecting rod (8201); the third sliding groove (8202) contains inert gas; a third scraper (8203) is slidably installed inside the third sliding groove (8202); the third scraper (8203) is elastically connected to the side wall of the inner cavity of the third sliding groove (8202) via a fifth spring (8204).

10. The control method for the secondary air system of a solid waste mixed combustion circulating fluidized bed boiler according to claim 9 is characterized in that: The steps include: S1: When the inspection staff observes through the transparent shell (41) whether bubbles appear on the colored film (42), it is used to determine whether the secondary air duct (9) is leaking; S2: The inspector observes through the transparent housing (61) whether the film (67) has a bright color, so as to judge whether the secondary air duct (9) is damaged; S3: After running for a period of time, the fluidized bed boiler (1) stops running, and the cleaning component (8) is started to clean the dust inside the secondary air nozzle (7); S4: After the dust cleaning is completed, the cleaning component (8) is reset and the fluidized bed boiler (1) starts to operate.

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