A thermal power generation boiler with waste heat recovery

Abstract

The present invention relates to the technical field of waste heat recovery, and specifically discloses a thermal power generation boiler with waste heat recovery, including an economizer installed in the boiler, the economizer including support frames on both sides and a circulating water pipe installed between the support frames, multiple groups of fin assemblies are installed on the outer wall of the circulating water pipe between the two support frames, and the gaps between the fin assemblies form a heat exchange area for the mixed gas of flue gas and ammonia to pass through, and the fin assembly has two states, state one, each fin assembly is in a parallel state, state two, there is a certain angle between two adjacent fin assemblies, and a vortex area is formed at the angle position. The present invention recycles the waste heat in the flue gas through multiple groups of fin assemblies, changes the state of the fins so that the fins guide the flow direction of the flue gas, slows down the flow speed of the flue gas by generating vortices in the flue gas, and cooperates with the vortex to fully fuse and react with the ammonia and sulfur and nitric compounds in the flue gas.

Description

Technical Field

[0001] The invention relates to the technical field of waste heat recovery, and in particular to a waste heat recovery thermal power generation boiler. Background Art

[0002] A boiler is an energy conversion device, which is mainly used to convert chemical energy or electrical energy in fuel into thermal energy, and then heat water or generate steam. Among them, an economizer is a device used to improve the thermal efficiency of industrial boilers. It recovers the waste heat in the boiler exhaust to preheat the boiler feed water. The economizer can significantly improve the thermal efficiency of the boiler, save fuel and reduce operating costs.

[0003] For example, Chinese patent number CN115789608A discloses an economizer and a waste heat boiler having the economizer, comprising at least two economizer bodies connected in series, the economizer body comprising a smoke box, the smoke box consisting of an upper box body and a lower box body, the upper box body and the lower box body are connected through a flue, the upper box body and the lower box body are both provided with at least two layers of tube rows connected to each other, the tube rows in the upper box body and the tube rows in the lower box body are connected to each other, and an economizer body The tube row is a finned tube row, and the tube row of the other economizer body is a bare tube row; the high-temperature flue gas used for waste heat recovery first enters the economizer body whose tube row is a bare tube row, and then enters the economizer body whose tube row is a finned tube row; the high-temperature flue gas used for waste heat recovery enters the economizer body from the lower box body, enters the upper box body through the flue, and is finally discharged from the upper box body. The economizer of this invention has the advantages of not easy to scale, small resistance, high heat exchange efficiency and not easy to produce leakage points.

[0004] However, since the flue gas generated after coal combustion contains a large amount of sulfides and nitrates, these compounds will not only pollute the environment but also affect the operating efficiency of the boiler. Therefore, the flue gas needs to be denitrated or desulfurized. At present, most boilers use ammonia to react with sulfides and nitrates in the flue gas to eliminate them. However, if the ammonia used as a reducing agent does not fully participate in the reaction, some unreacted ammonia will be discharged into the atmosphere with the flue gas, resulting in ammonia escape. It will not only cause irritation to the human respiratory tract and eyes, but may even cause chronic diseases, which may lead to environmental and human health problems. Summary of the invention

[0005] The object of the present invention is to provide a thermal power generation boiler with waste heat recovery to solve at least one technical problem existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following technical solution: a thermal power generation boiler with waste heat recovery, comprising an economizer installed in the boiler, the economizer comprising support frames on both sides and a circulating water pipe installed between the support frames, a plurality of groups of fin assemblies are installed on the outer wall of the circulating water pipe between the two support frames, and the gaps between the fin assemblies form a heat exchange area for the mixed gas of flue gas and ammonia to pass through;

[0007] The fin assembly has two states: state one, each fin assembly is in a parallel state; state two, there is a certain angle between two adjacent fin assemblies, and a vortex area is formed at the angle position.

[0008] Preferably, the fin assembly includes a long plate assembly and a short plate assembly, and the long plate assembly and the short plate assembly are alternately distributed on the outer wall of the circulating water pipe;

[0009] The long plate assembly comprises a fixed long plate fixedly mounted on the outer wall of the circulating water pipe through a perforation, a rotating shaft is fixedly mounted on both sides of the fixed long plate, and two long fins with a height half the height of the fixed long plate are rotatably mounted on the outer wall of the rotating shaft;

[0010] The short plate assembly comprises a fixed short plate fixedly mounted on the outer wall of the circulating water pipe through a perforation, a rotating shaft is fixedly mounted on both sides of the fixed short plate, and four short fins with a height half that of the fixed short plate are rotatably mounted on the outer wall of the rotating shaft, and the four short fins are grouped in pairs and can form fins with the same thickness as the fixed short plate;

[0011] The utility model also comprises a driving component for driving the short fins and the long fins to rotate and adjust.

[0012] Preferably, the driving assembly is arranged on the special-shaped plate 1 and the special-shaped plate 2 on the same side of the short fin and the long fin, and the special-shaped plate 1 and the special-shaped plate 2 can be moved and adjusted relative to or opposite to each other;

[0013] The outer walls of the long fins close to the support frames on both sides are rotatably connected to a rotating rod, the outer walls of each of the long fins located in the middle part are rotatably connected to two rotating rods, and the outer walls of each of the short fins are rotatably connected to a connecting rod. Sliders are rotatably connected between adjacent rotating rods and connecting rods, and two adjacent sliders are set as a group. Each group of sliders is slidably installed on the special-shaped plate one and the special-shaped plate two, and are alternately arranged.

[0014] Preferably, the side walls of the support frame on both sides are provided with sliding grooves, and sliding blocks that can be adjusted to move closer or farther away from each other are installed in the sliding grooves, and the special-shaped plate 1 and the special-shaped plate 2 are respectively fixed in the two sliding blocks;

[0015] The special-shaped plate 1 and the special-shaped plate 2 are set to be symmetrically bent, the intersection of the special-shaped plate 1 and the special-shaped plate 2 is set to be an I-shaped inclined plate, and the intersection of the special-shaped plate 2 and the special-shaped plate 1 is provided with an inclined groove for the I-shaped inclined plate to pass through and slide in it.

[0016] Preferably, the thickness of the end of the long fin far away from the circulating water pipe is inversely proportional to the distance between the long fin and the circulating water pipe.

[0017] Preferably, the multiple groups of short fins are rotatably mounted on the outer wall of the rotating shaft through sleeves, and the multiple groups of long fins are also rotatably mounted on the outer wall of the rotating shaft through sleeves, and each sleeve does not contact each other.

[0018] Preferably, the length of the fixed long plate is more than 1 / 3 of the length of the fixed short plate.

[0019] Preferably, the slider is slidably mounted on the outer wall of the special-shaped plate one or the special-shaped plate two via a slide rail.

[0020] Preferably, the surfaces of the short fins and the long fins are sprayed with a smooth and corrosion-resistant coating.

[0021] Preferably, at least one economizer is provided in the boiler, and a dust removal device is provided in the flue behind the economizer.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention can not only recycle the waste heat in the flue gas through multiple groups of fin assemblies, but also change the state of the fins so that the fins can guide the flow direction of the flue gas, so that the flue gas generates vortices, which can not only slow down the flow speed of the flue gas in the vortex area, but also cooperate with the vortex to fully fuse and react ammonia with sulfur and nitric compounds in the flue gas. In addition, the high-temperature flue gas still flows closely to the outer wall of the fin assembly before the vortex is generated, avoiding the vortex from reducing the efficiency of heat conduction in the flue gas to the fin assembly, so that the economizer can still maintain efficient waste heat recovery.

[0024] 2. The present invention drives the short fins and the long fins to rotate and adjust through a driving component, so that an angle is generated between the short fins and the long fins, so that the short fins and the long fins act as induced draft plates to drain the flue gas, and cooperate with the vibration and vortex generated by the flue gas to fully integrate the ammonia and sulfur or nitric compounds in the flue gas, and can also fully react the sulfur or nitric compounds removed from the economizer with ammonia, thereby cleaning the economizer while avoiding the escape of ammonia. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0026] Figure 2 A top view of the present invention;

[0027] Figure 3 This is a schematic diagram of the smoke flow direction before adjustment of the present invention;

[0028] Figure 4 This is a schematic diagram of the smoke flow direction after adjustment according to the present invention;

[0029] Figure 5 It is a schematic diagram of the three-dimensional structure of the driving component of the present invention;

[0030] Figure 6 It is a schematic diagram of the three-dimensional structure of the short plate assembly of the present invention;

[0031] Figure 7 It is a schematic diagram of the three-dimensional structure of the long board assembly of the present invention;

[0032] Figure 8 For the present invention Figure 4 A partial enlarged view of the middle part;

[0033] Fig. 9 The present invention is a flowchart of the operation process.

[0034] In the figure: 1, support frame; 2, sliding groove; 3, sliding block; 4, special-shaped plate 1; 5, special-shaped plate 2; 6, circulating water pipe; 7, slider; 8, I-shaped inclined plate; 9, inclined groove; 10, rotating rod; 11, connecting rod; 12, fixed short plate; 13, rotating shaft; 14, short fin; 15, fixed long plate; 16, long fin; 17, perforation; 18, sleeve; 19, rotating shaft. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] See also Figures 1 to 9 The present invention provides a technical solution: a thermal power generation boiler with waste heat recovery, comprising an economizer installed in the boiler, the economizer comprising support frames 1 on both sides and a circulating water pipe 6 installed between the support frames 1, a plurality of fin assemblies are installed on the outer wall of the circulating water pipe 6 between the two support frames 1, and the gaps between the fin assemblies form a heat exchange area for the mixed gas of flue gas and ammonia to pass through;

[0037] The fin assembly has two states: in state one, the fin assemblies are in parallel state; in state two, there is a certain angle between two adjacent fin assemblies, and a vortex area is formed at the angle position.

[0038] The methods of generating electricity using the energy contained in combustibles are collectively referred to as thermal power generation. Among them, the proportion of power generation using the burning of coal is about 67% of thermal power. However, the combustion of coal will produce a large amount of carbon dioxide and other harmful gas emissions, leading to environmental problems such as air pollution and climate change. Therefore, in boilers that use coal as the main fuel, a series of processes such as flue gas desulfurization, flue gas denitrification, dust removal, energy conservation and carbon reduction are required to reduce the pollution caused by power generation to the environment. Among them, denitrification, desulfurization and dust removal are used to make the flue gas meet the emission standards after treatment, and energy conservation and carbon reduction are used to recycle the heat energy in the high-temperature flue gas.

[0039] At present, most boilers use ammonia to react with sulfides and nitrates in flue gas to eliminate them. However, if the ammonia used as a reducing agent does not fully participate in the reaction, some unreacted ammonia will be discharged into the atmosphere with the flue gas, which will irritate the human respiratory tract and eyes, and even cause chronic diseases, which may lead to environmental and human health problems. In addition, some units are prone to ammonium bisulfate adhesion, dust accumulation, and blockage on the economizer, reducing the operating efficiency of the boiler. Therefore, the present invention discloses a thermal power generation boiler with waste heat recovery, which is used to reduce the escape of ammonia in the process of recovering waste heat in flue gas. The specific implementation method is as follows:

[0040] When using this device, please refer to Fig. 9 , Fig. 9 The present invention is an operation process of an existing boiler. The present invention only improves the economizer part, so the operation process of the rest of the parts will not be repeated. The flue gas generated after the fuel is burned passes through the economizer, desulfurization, denitrification and dust removal equipment, etc., and meets the emission standards before being discharged from the boiler.

[0041] Among them, when the high-temperature flue gas reaches the economizer, the ammonia injection equipment injects ammonia into the flue gas so that the ammonia can act as a reactant or reducing agent to remove sulfur or nitrate compounds in the flue gas under high temperature and high pressure. Then the mixed gas of flue gas and ammonia passes through the heat exchange area formed by the fin assembly of the economizer. When the ammonia can fully participate in the reaction, please refer to the specific Figure 3 The fin assemblies are in a mutually parallel state in state 1. After absorbing the waste heat in the flue gas, the fin assemblies transfer the heat to the circulating water pipe 6. The circulating water in the circulating water pipe 6 takes away the heat and transports it to the air heater or other devices that can reuse the heat, so as to achieve the purpose of heat recovery in the high-temperature flue gas. The mixed gas of ammonia and flue gas is combined again after being diverted by the economizer, so that the ammonia and the sulfur or nitric compounds in the flue gas can fully react.

[0042] When the exhaust pipe detects that the ammonia content in the flue gas discharged from the boiler is too high, the fin assembly switches to state 2, such as Figure 4In the state shown, there is a certain angle between two adjacent fin assemblies, and a vortex area is formed at the angle position, so that the ammonia can further react with the nitrate or sulfide in the flue gas, allowing the ammonia to fully participate in the reaction process, avoiding damage to the environment caused by excessive ammonia emissions and avoiding the phenomenon of ammonia escape.

[0043] In this way, multiple groups of fin assemblies recycle the waste heat in the flue gas while changing the state of the fins to guide the flow direction of the flue gas. By causing the flue gas to generate vortexes, not only can the speed of the flue gas flow in the vortex area be slowed down, but the ammonia and sulfur and nitric compounds in the flue gas can be fully integrated and reacted with the vortex. Moreover, the high-temperature flue gas still flows close to the outer wall of the fin assembly before the vortex is generated, avoiding the vortex from reducing the efficiency of heat conduction in the flue gas to the fin assembly, so that the economizer can still maintain efficient waste heat recovery.

[0044] Further, the fin assembly includes a long plate assembly and a short plate assembly, and the long plate assembly and the short plate assembly are alternately distributed on the outer wall of the circulating water pipe 6;

[0045] The long plate assembly includes a fixed long plate 15 fixedly mounted on the outer wall of the circulating water pipe 6 through a perforation 17, a rotating shaft 13 is fixedly mounted on both sides of the fixed long plate 15, and two long fins 16 with a height half the height of the fixed long plate 15 are rotatably mounted on the outer wall of the rotating shaft 13;

[0046] The short plate assembly includes a fixed short plate 12 fixedly mounted on the outer wall of the circulating water pipe 6 through a perforation 17, and a rotating shaft 19 is fixedly mounted on both sides of the fixed short plate 12. Four short fins 14 with a height half that of the fixed short plate 12 are rotatably mounted on the outer wall of the rotating shaft 19, and the four short fins 14 are grouped in pairs and can form fins with the same thickness as the fixed short plate 12;

[0047] The utility model also comprises a driving assembly for driving the short fins 14 and the long fins 16 to rotate and adjust.

[0048] According to the above embodiment, since the long plate components and the short plate components are alternately distributed on the outer wall of the circulating water pipe 6, when the high-temperature flue gas flows between the long fins 16 and the short fins 14, the height difference between the long fins 16 and the short fins 14 will cause the flue gas to vibrate irregularly, so that when the flue gas flows through the economizer, the ammonium bisulfate produced by the reaction of ammonia and sulfide cannot adhere to, accumulate dust, or clog the economizer due to the vibration, and for the ammonium bisulfate that has already adhered to the economizer, the vibration of the flue gas drives the economizer to vibrate slightly, which can It can shake off the ammonium bisulfate adhering to it, avoid the reduction of heat transfer efficiency due to dust accumulation and blockage on the economizer, so as to achieve the purpose of cleaning the economizer. The sulfur or nitro compounds and other solid small particles on the economizer can also be shaken off by vibration, so that the sulfur or nitro compounds can fully react with the ammonia in the flue gas, and improve the reaction efficiency in the process of flue gas denitrification and desulfurization, avoid sulfur or nitro compounds and other solid small particles from being adsorbed on the economizer, making it impossible for ammonia to fully react, and further eliminate the possibility of ammonia escape.

[0049] When the exhaust pipe detects that ammonia is escaping, the short fin 14 and the long fin 16 can be driven by the driving assembly to rotate and adjust so that an angle is generated between the short fin 14 and the long fin 16. Figure 4 The short fins 14 and the long fins 16 act as induced draft plates to guide the flue gas, and cooperate with the vibration and vortex mentioned above to fully integrate the ammonia and sulfur or nitric compounds in the flue gas. The sulfur or nitric compounds removed from the economizer can also fully react with ammonia, thereby cleaning the economizer while avoiding the escape of ammonia.

[0050] Furthermore, the driving assembly is arranged on the special-shaped plate 1 4 and the special-shaped plate 2 5 on the same side of the short fin 14 and the long fin 16, and the special-shaped plate 1 4 and the special-shaped plate 2 5 can be moved and adjusted relative to or opposite to each other;

[0051] The outer walls of the long fins 16 close to the support frames 1 on both sides are rotatably connected to a rotating rod 10, the outer walls of each long fin 16 located in the middle part are rotatably connected to two rotating rods 10, the outer walls of each short fin 14 are rotatably connected to a connecting rod 11, and the adjacent rotating rods 10 and connecting rods 11 are rotatably connected to a slider 7, and two adjacent sliders 7 are set as a group, and each group of sliders 7 is slidably installed on the special-shaped plate 1 4 and the special-shaped plate 2 5, respectively, and are alternately arranged.

[0052] In this embodiment, an implementation method for driving the short fins 14 and the long fins 16 to rotate and adjust is provided. Figure 5 and Figure 8When the special-shaped plate 1 4 and the special-shaped plate 2 5 are relatively close to each other, the sliders 7 in the same group are close to or away from each other and drive the rotating rod 10 and the connecting rod 11 thereon to rotate together, pulling the two adjacent short fins 14 on one side away from each other with the rotating shaft 19 as the center, and the short fins 14 on the other side cannot rotate due to the resistance, and at the same time, the two groups of long fins 16 on one side are pulled close to each other with the rotating shaft 13 as the center, and the two groups of long fins 16 on the other side are moved away from each other, so that the long fins 16 and the short fins 14 on the same side rotate alternately, that is, the two groups of short fins 14 between each two groups of long fins 16 are symmetrically arranged with the adjacent vertical short fins 14 as the axis, and finally switch to Figure 8 In the state shown, when the flue gas passes between two long fins 16 close to each other, refer to the direction shown by L in the figure, part of the flue gas L1 will pass through the gap between the short fin 14 and the long fin 16, while the other part of the flue gas L2 will first impact between the two opened short fins 14, and after being blocked, it will return and pass through driven by L1. In this way, the flue gas L1 and L2 will converge again to form a vortex area in the gap between the two short fins 14 and the long fin 16, so as to achieve the above-mentioned slowing down of the flue gas flow speed and make the ammonia fully react with the sulfur or nitric compounds in the flue gas to avoid the problem of ammonia escape.

[0053] Similarly, when the smoke passes between two long fins 16 that are far away from each other, that is, the state shown by L3 in the figure, the smoke at this time will pass through the gap between the long fin 16 and the short fin 14 below. As the gap gradually decreases, the overall smoke flow rate in the area decreases, and the overall smoke flow rate slows down, while the smoke flow rate at the local position of L3 increases, thereby further improving the heat exchange effect at this position.

[0054] On the contrary, when the special-shaped plate 1 4 and the special-shaped plate 2 5 are relatively far away, the short fin 14 and the long fin 16 return to Figure 3 status.

[0055] In this way, by making the special-shaped plate 1 4 and the special-shaped plate 2 5 relatively close to or far away from each other, the rotation adjustment of the long fin 16 and the short fin 14 can be completed, so that the flue gas can quickly pass through the heat exchange area between the long fin 16 and the short fin 14 under normal conditions, thereby improving the heat exchange efficiency. When ammonia escapes, the ammonia can also be fully reacted with sulfur and nitric compounds by adjusting the angle between the long fin 16 and the short fin 14, so as to avoid ammonia pollution and damage to the external environment.

[0056] Furthermore, the side walls of the support frame 1 on both sides are provided with sliding grooves 2, and sliding blocks 3 that can be adjusted to move closer or farther away from each other are installed in the sliding grooves 2, and the special-shaped plate 1 4 and the special-shaped plate 2 5 are respectively fixed in the two sliding blocks 3;

[0057] The special-shaped plate 1 4 and the special-shaped plate 2 5 are set to be symmetrically bent, and the intersection of the special-shaped plate 1 4 and the special-shaped plate 2 5 is set to be an I-shaped inclined plate 8, and the intersection of the special-shaped plate 2 5 and the special-shaped plate 1 4 is provided with an inclined groove 9 for the I-shaped inclined plate 8 to pass through and slide in it.

[0058] According to the above embodiment, the special-shaped plate 1 4 is composed of multiple sets of parallel plates and I-shaped inclined plates 8 alternately, and the special-shaped plate 2 5 is composed of multiple sets of parallel plates and inclined plates. Figure 5 Therefore, the special-shaped plate 1 4 and the special-shaped plate 2 5 can be arranged crosswise in the same vertical plane, so that the special-shaped plate 1 4 and the special-shaped plate 2 5 can simultaneously drive two adjacent groups of long fins 16 and short fins 14, that is, the long fins 16 and the short fins 14 on both sides of the special-shaped plate 1 4 and the special-shaped plate 2 5 can be rotated and adjusted at the same time, and the operation speed of the device can be increased on the basis of improving the structural strength, so that the smoke can be more uniform when passing through the long fins 16 and the short fins 14, thereby improving the heat exchange efficiency between the long fins 16 and the short fins 14 and the smoke.

[0059] Furthermore, the thickness of the end of the long fin 16 far away from the circulating water pipe 6 is inversely proportional to the distance between the end of the long fin 16 and the circulating water pipe 6 .

[0060] According to the above embodiment, since the thickness of the long fin 16 is thinner as it is farther away from the circulating water pipe 6, the wind pressure generated on both sides of the long fin 16 by the flue gas when passing through the long fin 16 becomes greater and greater, causing the end of the long fin 16 to swing slightly, thereby shaking off the solid small particles of sulfur and nitro compounds attached to the outer wall of the long fin 16 and the ammonium bisulfate produced by the reaction of ammonia and sulfide. This not only prevents the ammonium bisulfate from adhering to the surface of the economizer and accumulating ash, thereby reducing the thermal efficiency transfer of the economizer, but also allows the solid small particles produced by the sulfur and nitro compounds to further fully fuse and react, thereby improving the effects of denitrification and desulfurization and eliminating excess ammonia.

[0061] Furthermore, multiple groups of short fins 14 are rotatably mounted on the outer wall of the rotating shaft 19 through sleeves 18, and multiple groups of long fins 16 are also rotatably mounted on the outer wall of the rotating shaft 13 through sleeves 18, and each sleeve 18 does not contact each other.

[0062] According to the above-mentioned embodiment, due to the arrangement of multiple groups of sleeves 18, multiple groups of short fins 14 on the same axis and multiple groups of long fins 16 on the same axis will not interfere with each other's travel due to mutual friction or collision when performing rotation adjustment, thereby avoiding jamming caused by rotation interference or individual long fins 16 and short fins 14 being unable to rotate to a predetermined position, which makes it impossible for flue gas to pass through the economizer evenly, reduces the heat exchange efficiency between the flue gas and the economizer, reduces the adjustment effect, reduces the vibration cleaning effect of the flue gas flow on the economizer, and affects the generation of vortexes, which may cause ammonia and sulfur or nitric compounds to fail to fully fuse and react.

[0063] Furthermore, the length of the fixed long plate 15 is greater than 1 / 3 of the length of the fixed short plate 12 .

[0064] By limiting the length difference between the fixed long plate 15 and the fixed short plate 12, it is prevented that the long fins 16 and the short fins 14 are closed to each other during rotation adjustment, thereby sealing the heat exchange area and preventing the airflow in the exhaust duct from passing normally, affecting the waste heat recovery efficiency, and even seriously hindering the air circulation in the boiler, making it impossible for combustion to proceed normally.

[0065] Furthermore, the slider 7 is slidably installed on the outer wall of the special-shaped plate 1 4 or the special-shaped plate 2 5 through a slide rail.

[0066] Specifically, a dovetail groove or the like can be used to prevent the slider 7 from being separated from the outer wall of the special-shaped plate 1 4 or the special-shaped plate 2 5 when sliding on the outer wall of the special-shaped plate 1 4 or the special-shaped plate 2 5, thereby causing the adjustment function of the device to fail.

[0067] Furthermore, the surfaces of the short fins 14 and the long fins 16 are sprayed with a smooth and corrosion-resistant coating.

[0068] According to the above embodiment, since the flue gas contains a large amount of small solid particles, in order to prevent the small solid particles from being adsorbed on the outer walls of the short fins 14 and the long fins 16, the outer walls of the short fins 14 and the long fins 16 are blocked so that the heat in the flue gas cannot be transferred to the circulating water in the circulating water pipe 6. The surfaces of the short fins 14 and the long fins 16 are sprayed with a smooth metal coating. Since the flue gas contains a large amount of acidic or alkaline substances, as well as corrosive substances such as heavy metals and sulfides, the outer walls of the short fins 14 and the long fins 16 are made of corrosion-resistant materials or coatings, such as aluminized steel or 316L stainless steel.

[0069] Furthermore, at least one economizer is arranged in the boiler, and a dust removal device is provided in the flue behind the economizer.

[0070] According to the above implementation mode, since there is still a large amount of waste heat in the flue gas passing through the economizer, multiple sets of economizers can be set in the flue to recover the waste heat of flue gases at different temperatures and improve the heat utilization efficiency. The dust removal equipment in the flue, such as electrostatic precipitator or cyclone separator, can remove small solid particles in the flue gas so that the flue gas can meet the emission standards after treatment.

[0071] The standard parts used in this embodiment can be purchased directly from the market, and the non-standard structural components recorded in the specification and the drawings can also be directly processed according to the existing technical common sense. At the same time, the connection method of each component adopts the mature conventional means in the prior art, and the machinery, parts and equipment all adopt the conventional models in the prior art, so no specific description will be given here.

[0072] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thermal power generation boiler with waste heat recovery, comprising an economizer installed in the boiler, characterized in that: The economizer comprises support frames (1) on both sides and a circulating water pipe (6) installed between the support frames (1); a plurality of fin assemblies are installed on the outer wall of the circulating water pipe (6) between the two support frames (1); and the gaps between the fin assemblies form a heat exchange area for a mixed gas of flue gas and ammonia to pass through; The fin assembly has two states: state one, each fin assembly is in a parallel state; state two, there is a certain angle between two adjacent fin assemblies, and a vortex area is formed at the angle position; The fin assembly comprises a long plate assembly and a short plate assembly, and the long plate assembly and the short plate assembly are alternately distributed on the outer wall of the circulating water pipe (6); The long plate assembly comprises a fixed long plate (15) fixedly mounted on the outer wall of the circulating water pipe (6) through a perforation (17), a rotating shaft (13) being fixedly mounted on both sides of the fixed long plate (15), and two long fins (16) having a height half that of the fixed long plate (15) being rotatably mounted on the outer wall of the rotating shaft (13); The short plate assembly comprises a fixed short plate (12) fixedly mounted on the outer wall of the circulating water pipe (6) through a perforation (17), a rotating shaft (19) being fixedly mounted on both sides of the fixed short plate (12), and four short fins (14) having a height half that of the fixed short plate (12) being rotatably mounted on the outer wall of the rotating shaft (19), and the four short fins (14) are arranged in groups of two and can form fins having the same thickness as the fixed short plate (12); It also includes a driving assembly for driving the short fins (14) and the long fins (16) to rotate and adjust.

2. The waste heat recovery thermal power generation boiler according to claim 1, characterized in that: The driving assembly is arranged on the special-shaped plate 1 (4) and the special-shaped plate 2 (5) on the same side of the short fin (14) and the long fin (16), and the special-shaped plate 1 (4) and the special-shaped plate 2 (5) can be moved and adjusted relative to or opposite to each other; The outer walls of the long fins (16) close to the support frames (1) on both sides are rotatably connected to a rotating rod (10), the outer walls of each of the long fins (16) located in the middle part are rotatably connected to two rotating rods (10), the outer walls of each of the short fins (14) are rotatably connected to a connecting rod (11), and a slider (7) is rotatably connected between adjacent rotating rods (10) and connecting rods (11), and two adjacent sliders (7) are set as a group, and each group of sliders (7) is slidably installed on the special-shaped plate 1 (4) and the special-shaped plate 2 (5), respectively, and are arranged alternately.

3. The waste heat recovery thermal power generation boiler according to claim 2, characterized in that: The side walls of the support frame (1) on both sides are provided with sliding grooves (2), and sliding blocks (3) that can be adjusted to move closer or farther away from each other are installed in the sliding grooves (2), and the special-shaped plate 1 (4) and the special-shaped plate 2 (5) are respectively fixed in the two sliding blocks (3); The special-shaped plate 1 (4) and the special-shaped plate 2 (5) are arranged in mutually symmetrical bending shapes, the intersection of the special-shaped plate 1 (4) and the special-shaped plate 2 (5) is arranged as an I-shaped inclined plate (8), and the intersection of the special-shaped plate 2 (5) and the special-shaped plate 1 (4) is provided with an inclined groove (9) for the I-shaped inclined plate (8) to pass through and slide in.

4. The waste heat recovery thermal power generation boiler according to claim 3, characterized in that: The thickness of the end of the long fin (16) far away from the circulating water pipe (6) is inversely proportional to the distance between the long fin (16) and the circulating water pipe (6).

5. The waste heat recovery thermal power generation boiler according to claim 4, characterized in that: The plurality of groups of short fins (14) are rotatably mounted on the outer wall of the rotating shaft (19) via sleeves (18), and the plurality of groups of long fins (16) are also rotatably mounted on the outer wall of the rotating shaft (13) via sleeves (18), and each sleeve (18) does not contact each other.

6. The waste heat recovery thermal power generation boiler according to claim 5, characterized in that: The length of the fixed long plate (15) is more than 1 / 3 of the length of the fixed short plate (12).

7. The thermal power generation boiler with waste heat recovery according to claim 6, characterized in that: The slider (7) is slidably mounted on the outer wall of the first special-shaped plate (4) or the second special-shaped plate (5) via a slide rail.

8. The thermal power generation boiler with waste heat recovery according to any one of claims 1 to 7, characterized in that: The surfaces of the short fins (14) and the long fins (16) are sprayed with a smooth and corrosion-resistant coating.

9. The thermal power generation boiler with waste heat recovery according to any one of claims 1 to 8, characterized in that: At least one economizer is arranged in the boiler, and a dust removal device is arranged in the flue behind the economizer.

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