Corner tube boiler of circulating fluidized bed

Abstract

The utility model discloses a corner tube boiler of a circulating fluidized bed, which comprises a circulating water pipe frame which comprises a boiler barrel, an outlet pipe, an upper header arranged on the periphery of the top, a lower header arranged on the periphery of the bottom and downcomers arranged on the periphery. The circulating fluidized bed boiler body is arranged in the circulating water pipe frame, the boiler wall of the circulating fluidized bed boiler body comprises a membrane type water cooling wall, the bottom end of the membrane type water cooling wall is connected with lower collecting boxes arranged on the periphery of the bottom, and the top end of the membrane type water cooling wall is connected with upper collecting boxes arranged on the periphery of the top; a main combustion chamber, an auxiliary combustion chamber, a burnout chamber, a water-cooling separator and a tail vertical shaft which are sequentially connected are arranged in the circulating fluidized bed boiler body. According to the circulating fluidized bed corner tube boiler, the aims of high efficiency, low cost and low emission can be achieved by combining the circulating water pipe frame of the corner tube boiler and the circulating fluidized bed boiler body adopting a circulating fluidized bed combustion mode.

Description

Technical Field

[0001] The utility model belongs to the technical field of industrial boilers, and in particular relates to a circulating fluidized bed corner tube boiler. Background Art

[0002] With the rapid development of urbanization and industrialization in my country, boilers have entered a period of rapid development. While users have high requirements for boiler efficiency, they also hope to save costs as much as possible. At present, circulating fluidized bed boilers have strong adaptability to fuels, full combustion, high thermal efficiency, and good emission effects, but the main steel frame structure is large, the steel consumption is high, and the overall cost is high. Corner tube boilers use full membrane water-cooled walls, self-supporting structures, and advanced water circulation methods, with low consumables, but the flag-type heating surface of the corner tube boiler is complex to assemble and difficult to maintain, and most of them are grate boilers, which have poor fuel adaptability, low combustion efficiency, and high pollution emissions. Utility Model Content

[0003] The utility model aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one purpose of the utility model is to provide a circulating fluidized bed angle tube boiler, which can achieve the goals of high efficiency, low cost and low emission by combining a circulating water tube rack of the angle tube boiler and a circulating fluidized bed boiler body adopting a circulating fluidized bed combustion method.

[0004] In one aspect of the utility model, the utility model proposes a circulating fluidized bed corner tube boiler. According to an embodiment of the utility model, the circulating fluidized bed corner tube boiler includes: a circulating water pipe rack, the circulating water pipe rack includes a boiler drum, an outlet pipe, an upper header arranged around the top, a lower header arranged around the bottom, and downcomers arranged around the four sides, the boiler drum is connected to the downcomer, the downcomer is connected to the lower header, and the upper header is connected to the boiler drum through the outlet pipe; a circulating fluidized bed boiler body, the circulating fluidized bed boiler body is arranged in the circulating water pipe rack, and the furnace wall of the circulating fluidized bed boiler body includes a membrane The membrane water-cooled wall is respectively connected to the lower headers arranged around the bottom, and the top of the membrane water-cooled wall is respectively connected to the upper headers arranged around the top. The circulating fluidized bed boiler body is provided with a main combustion chamber, an auxiliary combustion chamber, a burnout chamber, a water-cooled separator and a tail shaft connected in sequence. A primary air distribution device is provided at the bottom of the main combustion chamber, and a serpentine tube heating surface is provided in the tail shaft. The bottom end of the serpentine tube heating surface is connected to the lower header, and the top end of the serpentine tube heating surface is connected to the water outlet header.

[0005] According to the circulating fluidized bed corner tube boiler of the above embodiment of the utility model, by adopting a circulating water pipe rack, the overall steel consumption of the boiler can be reduced, refractory materials can be saved, and thus the investment cost can be reduced; compared with conventional boilers, the circulating fluidized bed boiler body adopting the circulating fluidized bed combustion method has the advantages of high combustion efficiency and strong fuel adaptability; the three-stage furnace including the main combustion chamber, the auxiliary combustion chamber and the burnout chamber is adopted, which is conducive to achieving efficient and sufficient combustion, thereby achieving the goal of high efficiency and low emission of the boiler; compared with the flag-type heating surface, the serpentine tube heating surface is adopted, which can help solve the problems of dust accumulation and corrosion; in addition, the furnace wall of the circulating fluidized bed boiler body adopts a membrane water-cooled wall, which can be easily installed and maintained.

[0006] In addition, the circulating fluidized bed corner tube boiler according to the above embodiment of the utility model may also have the following additional technical features:

[0007] In some embodiments of the present invention, the top of the main combustion chamber is connected to the top of the auxiliary combustion chamber.

[0008] In some embodiments of the present invention, the bottom of the auxiliary combustion chamber is communicated with the bottom of the burnout chamber.

[0009] In some embodiments of the present invention, the circulating fluidized bed boiler body further comprises an ash hopper, which is arranged below the auxiliary combustion chamber and the burnout chamber, and the bottom of the auxiliary combustion chamber and the bottom of the burnout chamber are both connected to the ash hopper.

[0010] In some embodiments of the present invention, the circulating fluidized bed boiler body further includes a first material returner, which is disposed at the bottom of the ash hopper and is communicated with the main combustion chamber.

[0011] In some embodiments of the present invention, the circulating fluidized bed boiler body further includes a second material returner, which is disposed at the bottom of the water-cooled separator and is communicated with the first material returner.

[0012] In some embodiments of the present invention, the circulating fluidized bed boiler body further comprises: a secondary air distribution device, and the secondary air distribution device is arranged around the main combustion chamber.

[0013] In some embodiments of the present invention, the circulating fluidized bed corner tube boiler further includes: a water-cooled air chamber, and the water-cooled air chamber is connected to the primary air distribution device.

[0014] In some embodiments of the present invention, the circulating fluidized bed corner tube boiler further includes: a feeding device, and the feeding device is connected to the main combustion chamber.

[0015] In some embodiments of the utility model, an air preheater is provided in the tail shaft, and the air preheater is provided below the heating surface of the serpentine tube.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 It is a structural schematic diagram of a circulating fluidized bed corner tube boiler according to an embodiment of the utility model;

[0019] Figure 2 It is a schematic structural diagram of the serpentine tube heating surface according to an embodiment of the utility model.

[0020] Reference numerals:

[0021] 100-circulating water pipe rack; 101-boiler drum; 102-lead-out pipe; 103-upper header; 104-lower header; 105-down pipe; 200-circulating fluidized bed boiler body; 201-membrane water-cooled wall; 202-main combustion chamber; 203-auxiliary combustion chamber; 204-burnout chamber; 205-water-cooled separator; 206-tail shaft; 207-separator outlet flue; 208-primary air distribution device; 209-serpentine tube heating surface; 210-ash hopper; 211-first return material; 212-second return material; 213-secondary air distribution device; 214-water-cooled air chamber; 215-feeding device; 216-air preheater. DETAILED DESCRIPTION

[0022] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0027] In one aspect of the present invention, the present invention provides a circulating fluidized bed corner tube boiler. According to an embodiment of the present invention, referring to Figure 1-2The circulating fluidized bed corner tube boiler comprises: a circulating water pipe rack 100 and a circulating fluidized bed boiler body 200. The circulating water pipe rack 100 comprises a boiler drum 101, an outlet pipe 102, an upper header 103 arranged around the top, a lower header 104 arranged around the bottom, and a downcomer 105 arranged around the drum 101. The boiler drum 101 is connected to the downcomer 105, the downcomer 105 is connected to the lower header 104, and the upper header 103 is connected to the boiler drum 101 through the outlet pipe 102. The circulating fluidized bed boiler body 200 is arranged in the circulating water pipe rack 100. The furnace wall of the circulating fluidized bed boiler body 200 comprises a membrane water-cooled wall 201. The bottom ends of the membrane water-cooled wall 201 are connected to the arranged The bottom is connected to the lower header 104, and the top of the membrane water-cooled wall 201 is respectively connected to the upper header 103 arranged around the top. The circulating fluidized bed boiler body 200 is provided with a main combustion chamber 202, an auxiliary combustion chamber 203, a burnout chamber 204, a water-cooled separator 205 and a tail shaft 206 which are connected in sequence. A primary air distribution device 208 is provided at the bottom of the main combustion chamber 202, and a serpentine tube heating surface 209 is provided in the tail shaft 206. The bottom end of the serpentine tube heating surface 209 is connected to the lower header 104, and the top end of the serpentine tube heating surface 209 is connected to the water outlet header.

[0028] According to the circulating fluidized bed corner tube boiler of the above embodiment of the utility model, a circulating water pipe rack 100 is adopted, which includes a boiler drum 101, an outlet pipe 102, an upper header 103 arranged around the top, a lower header 104 arranged around the bottom, and downcomers 105 arranged around the drum 101. At the same time, the boiler drum 101 is connected to the downcomer 105, and the downcomer 105 is connected to the lower header 104. The bottom end of the membrane water-cooled wall 201 of the circulating fluidized bed boiler body 200 is connected to the lower header 104, and the top end of the membrane water-cooled wall 201 is connected to the upper header 103. The upper header 103 is connected to the boiler drum 101 through the outlet pipe 102 to form a circulation loop. At the same time, the circulating water pipe rack 100 can support the circulating fluidized bed boiler body 200, thereby reducing the overall steel consumption of the boiler, saving refractory materials, and thus reducing Investment cost; Compared with conventional boilers, the circulating fluidized bed boiler body 200 using the circulating fluidized bed combustion method has the advantages of high combustion efficiency and strong fuel adaptability; By adopting a three-stage furnace including a main combustion chamber 202, an auxiliary combustion chamber 203 and a burnout chamber 204, it is conducive to achieving efficient and sufficient combustion, thereby achieving the goal of high efficiency and low emissions of the boiler; A primary air distribution device 208 is provided at the bottom of the main combustion chamber 202, and ignition under the bed can be adopted for rapid start-up; A water-cooled separator 205 is adopted to cool the material while capturing the material, thereby helping to avoid coking caused by ash return; Compared with the flag-type heating surface, the serpentine tube heating surface 209 can help solve the problems of ash accumulation and corrosion; In addition, the furnace wall of the circulating fluidized bed boiler body 200 adopts a membrane water-cooled wall 201, which can be easily installed and maintained. It should be noted that the type of the primary air distribution device 208 is not particularly limited, for example, it can be an air distribution plate with a hood. Furthermore, the furnace of the circulating fluidized bed boiler body 200 can be fully sealed around by a membrane water-cooled wall 201, and the lower part of the main combustion chamber 202 can be contracted into a bucket shape.

[0029] According to some specific embodiments of the present invention, the top of the main combustion chamber 202 is connected to the top of the auxiliary combustion chamber 203. Specifically, the incompletely burned high-temperature flue gas can enter the auxiliary combustion chamber 203 from the main combustion chamber 202 and continue to burn in the auxiliary combustion chamber 203, which is conducive to achieving efficient and sufficient combustion, thereby achieving the goal of high efficiency and low emissions of the boiler.

[0030] According to some further specific embodiments of the present invention, the bottom of the auxiliary combustion chamber 203 is connected to the bottom of the burnout chamber 204. Specifically, the incompletely burned high-temperature flue gas can enter the burnout chamber 204 from the auxiliary combustion chamber 203 and continue to burn in the burnout chamber 204, which is conducive to achieving efficient and sufficient combustion, thereby achieving the goal of high efficiency and low emissions of the boiler.

[0031] According to some further specific embodiments of the present invention, the membrane-type water-cooled wall of the rear wall of the burnout chamber 204 is bent, thereby avoiding waste of materials caused by adding a header, which is further beneficial to reducing investment costs.

[0032] According to some other specific embodiments of the present invention, the water-cooled separator 205 may be a square water-cooled separator surrounded by membrane water-cooled walls.

[0033] According to some other specific embodiments of the present invention, the tail shaft 206 is surrounded by membrane water-cooled walls.

[0034] According to some other specific embodiments of the utility model, a separator outlet flue 207 is provided at the top of the water-cooled separator 205, and the water-cooled separator 205 is connected to the tail shaft 206 through the separator outlet flue 207. Specifically, the separator outlet flue 207 can be formed by bending a membrane water-cooled wall. As a specific example, the rear wall of the water-cooled separator 205 can be shared with the front wall of the tail shaft 206 and bent upward to form the top of the water-cooled separator 205, and then extended to the rear wall of the tail shaft 206 to form the separator outlet flue 207.

[0035] According to some other specific embodiments of the utility model, the circulating fluidized bed boiler body further includes an ash hopper 210, which is arranged below the auxiliary combustion chamber 203 and the burnout chamber 204, and the bottom of the auxiliary combustion chamber 203 and the bottom of the burnout chamber 204 are both connected to the ash hopper. When passing through the ash hopper 210 at the bottom of the auxiliary combustion chamber 203 and the burnout chamber 204, a part of the particles carried in the high-temperature flue gas are separated due to inertial sedimentation, and the separated particles are collected and discharged through the ash hopper 210, thereby facilitating dust removal of the high-temperature flue gas.

[0036] According to some other specific embodiments of the utility model, the circulating fluidized bed boiler body also includes a first returner 211, which is arranged at the bottom of the ash hopper 210, and the first returner 211 is connected to the main combustion chamber 202. Specifically, the particulate matter collected by the ash hopper 210 can be returned to the bed through the first returner 211 for circulation and re-combustion, so that the fuel is fully burned and burned out, which is beneficial to improving the combustion efficiency, has strong adaptability to fuel, and can efficiently burn inferior fuel, thereby helping to improve the utilization efficiency of energy and reduce the emission of waste. It should be noted that the type of the first returner 211 is not particularly limited, for example, it can be a U-shaped valve.

[0037] According to some other specific embodiments of the utility model, the circulating fluidized bed boiler body also includes a second returner 212, which is arranged at the bottom of the water-cooled separator 205, and the second returner 212 is connected to the first returner 211. Thus, not only can two-stage circulation return be performed, but also the particulate matter separated by the water-cooled separator 205 can be returned to the bed for circulation and re-combustion through the second returner 212 and the first returner 211 in turn, which is further conducive to the fuel combustion and burnout, improves the combustion efficiency, enhances the fuel adaptability, and thus helps to improve the energy utilization efficiency and reduce the emission of waste, and can also make the circulating fluidized bed boiler body structure more compact, so as to have significant economy. It should be noted that the type of the second returner 212 is not particularly limited, for example, it can be a U-shaped valve.

[0038] According to some other specific embodiments of the utility model, the circulating fluidized bed boiler body also includes: a secondary air distribution device 213, and the secondary air distribution device 213 is arranged around the main combustion chamber 202. Specifically, secondary air can be distributed into the main combustion chamber 202 through the secondary air distribution device 213, which is conducive to the full combustion of fuel in the main combustion chamber 202, thereby helping to improve the efficiency of energy utilization and reduce waste emissions. It should be noted that the type of the secondary air distribution device 213 is not particularly limited, for example, it can be a nozzle. Furthermore, the secondary air distribution device 213 can be two layers, each layer including a plurality of nozzles.

[0039] According to some other specific embodiments of the present invention, the circulating fluidized bed corner tube boiler further includes: a water-cooled air chamber 214, which is connected to the primary air distribution device 208. Specifically, the primary air can be preheated and flow from the water-cooled air chamber 214 through the primary air distribution device 208 into the furnace.

[0040] According to some specific embodiments of the present invention, the circulating fluidized bed corner tube boiler further includes: a feeding device 215, and the feeding device 215 is connected to the main combustion chamber 202. Specifically, the fuel can enter the dense phase area of ​​the main combustion chamber 202 through the feeding device 215, and after being fluidized by the primary wind and disturbed by the secondary wind around the furnace, the fuel flows through the auxiliary combustion chamber 203 and the burnout chamber 204 to be fully burned. It should be noted that the type of the feeding device 215 is not particularly limited, for example, it can be a feeding pipe.

[0041] According to some specific embodiments of the present invention, an air preheater 216 is provided in the tail shaft 206, and the air preheater 216 is provided below the serpentine tube heating surface 209. Thus, the waste heat of the flue gas can be recovered by the air preheater 216, which is further conducive to improving the utilization efficiency of energy.

[0042] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0043] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A circulating fluidized bed corner tube boiler, characterized in that: include: A circulating water pipe rack, the circulating water pipe rack comprising a boiler drum, an outlet pipe, an upper header arranged around the top, a lower header arranged around the bottom, and downcomers arranged around the bottom, the boiler drum is connected to the downcomer, the downcomer is connected to the lower header, and the upper header is connected to the boiler drum via the outlet pipe; A circulating fluidized bed boiler body, wherein the circulating fluidized bed boiler body is arranged in the circulating water pipe rack, and the furnace wall of the circulating fluidized bed boiler body includes a membrane water-cooled wall, the bottom end of the membrane water-cooled wall is respectively connected to the lower header arranged around the bottom, and the top end of the membrane water-cooled wall is respectively connected to the upper header arranged around the top, and the circulating fluidized bed boiler body is provided with a main combustion chamber, an auxiliary combustion chamber, a burnout chamber, a water-cooled separator and a tail shaft connected in sequence, a primary air distribution device is provided at the bottom of the main combustion chamber, and a serpentine tube heating surface is provided in the tail shaft, the bottom end of the serpentine tube heating surface is connected to the lower header, and the top end of the serpentine tube heating surface is connected to the water outlet header.

2. The circulating fluidized bed corner tube boiler according to claim 1, characterized in that: The top of the main combustion chamber is communicated with the top of the auxiliary combustion chamber.

3. The circulating fluidized bed corner tube boiler according to claim 2, characterized in that: The bottom of the auxiliary combustion chamber is communicated with the bottom of the burnout chamber.

4. The circulating fluidized bed corner tube boiler according to claim 3, characterized in that: The circulating fluidized bed boiler body further comprises an ash hopper, which is arranged below the auxiliary combustion chamber and the burnout chamber, and the bottom of the auxiliary combustion chamber and the bottom of the burnout chamber are both connected to the ash hopper.

5. The circulating fluidized bed corner tube boiler according to claim 4, characterized in that: The circulating fluidized bed boiler body further comprises a first material returner, which is arranged at the bottom of the ash hopper and is communicated with the main combustion chamber.

6. The circulating fluidized bed corner tube boiler according to claim 5, characterized in that: The circulating fluidized bed boiler body further comprises a second material returner, which is arranged at the bottom of the water-cooled separator and is communicated with the first material returner.

7. The circulating fluidized bed corner tube boiler according to claim 1, characterized in that: The circulating fluidized bed boiler body also includes: A secondary air distribution device is arranged around the main combustion chamber.

8. The circulating fluidized bed corner tube boiler according to claim 7, characterized in that: Also includes: A water-cooled air chamber is connected to the primary air distribution device.

9. The circulating fluidized bed corner tube boiler according to claim 1, characterized in that: Also includes: A feeding device is communicated with the main combustion chamber.

10. The circulating fluidized bed corner tube boiler according to claim 1, characterized in that: An air preheater is arranged in the tail shaft and is arranged below the heating surface of the serpentine tube.

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