Supercritical once-through boiler water wall structure

Abstract

This invention relates to the field of power plant boiler technology and discloses a water-cooled wall structure for a supercritical once-through boiler, including a first connecting ring. Four connecting columns are fixedly connected to the outer wall of the first connecting ring, and a connecting plate is fixedly connected to the outer wall of each of the four connecting columns. A wrapping mechanism is fixedly connected to the inner side of each connecting plate. The wrapping mechanism includes a spiral coil, the outer wall of which is fixedly connected to the connecting plate. A lower header is fixedly connected to the bottom of the spiral coil, and a transition component is fixedly connected to the top of the spiral coil. A vertical component is fixedly connected to the top of the transition component. By setting the transition component, the flow path of the working fluid inside the shell is extended using a first, second, and third blocking ring, increasing the mixing time and mixing distance, allowing the working fluid from different areas to be fully mixed, effectively reducing temperature and flow deviations, and providing uniform inlet conditions for the subsequent vertical coil.

Description

Technical Field

[0001] This invention relates to the field of power plant boiler technology, specifically to a water-cooled wall structure for a supercritical once-through boiler. Background Technology

[0002] A supercritical once-through boiler is a once-through boiler with an operating pressure higher than the critical pressure, and it has no steam drum. Feedwater flows through the water-cooled wall tubes in a single pass, directly and continuously becoming superheated steam, without steam-water circulation or boiling. It has a compact structure and high thermal efficiency, and is widely used in large thermal power units and deep peak-shaving applications.

[0003] Patent application CN201810294466.5 discloses a water-cooled wall structure for a supercritical or ultra-supercritical once-through boiler, including a lower spiral section water-cooled wall and an upper vertical section water-cooled wall. The upper vertical section water-cooled wall includes an upper front wall water-cooled wall, an upper side wall water-cooled wall, a rear wall water-cooled wall slagging tube, a flame deflector water-cooled wall, a bottom water-cooled wall of the horizontal flue, and a side wall water-cooled wall of the horizontal flue. The lower spiral section water-cooled wall and the upper vertical section water-cooled wall are connected by a mixing header in the middle of the water-cooled wall. A water-cooled wall inlet header is provided at the inlet end of the lower spiral section water-cooled wall, and a water-cooled wall outlet header is provided at the outlet end of the upper vertical section water-cooled wall. The bottom water-cooled wall of the horizontal flue is connected to the slagging tube of the rear wall water-cooled wall through a slagging tube inlet header, and the bottom water-cooled wall of the horizontal flue is also connected to the side wall water-cooled wall of the horizontal flue through a side wall water-cooled wall inlet header.

[0004] When the existing equipment is in use, the working fluid output from the spiral tube coil directly enters the intermediate mixing header. However, the traditional header lacks an effective turbulence and path extension structure, resulting in short mixing time and insufficient mixing distance. This leads to insufficient mixing of working fluids from different locations, which can easily cause local overheating of the vertical tube, limiting the boiler's peak-shaving capacity and operational safety. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a water-cooled wall structure for a supercritical once-through boiler, thereby solving the problems mentioned in the background section.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a water-cooled wall structure for a supercritical once-through boiler, comprising a first connecting ring, wherein a connecting column is fixedly connected to the outer wall of the first connecting ring, the number of the connecting columns is four, a connecting plate is fixedly connected to the outer wall of the four connecting columns, and a wrapping mechanism is fixedly connected to the inner side of the connecting plate;

[0007] The parcel mechanism includes;

[0008] A spiral tube coil, wherein the outer wall of the spiral tube coil is fixedly connected to a connecting plate, a lower header is fixedly connected to the bottom of the spiral tube coil, a first outlet is provided at the top of the spiral tube coil, a transition component is fixedly connected to the top of the spiral tube coil, and a vertical component is fixedly connected to the top of the transition component.

[0009] According to the above technical solution, a second connecting ring is provided at the bottom of the first connecting ring. The outer wall of the second connecting ring is fixedly connected to the connecting column, and the inner wall of the second connecting ring is fixedly connected to the vertical component. The second connecting ring is used to stabilize the position of the vertical component.

[0010] According to the above technical solution, the top of the vertical component is fixedly connected to an upper header, and the inner wall of the first connecting ring is fixedly connected to the upper header, wherein the first connecting ring is used to fix the position of the upper header.

[0011] According to the above technical solution, the transition component includes a shell, the outer wall of the shell is fixedly connected to the connecting plate, the top of the shell is provided with a second water outlet, the bottom of the shell is provided with a first water inlet, the bottom of the first water inlet is fixedly connected to the first water outlet, wherein the working fluid inside the spiral tube enters the transition component through the first water outlet and the first water inlet, and is finally sent into the vertical component from the second water outlet.

[0012] According to the above technical solution, a first blocking ring is fixedly connected to the inner wall of the shell, a second blocking ring is fixedly connected to the outer wall of the first blocking ring, and a third blocking ring is fixedly connected to both the upper and lower ends of the inner wall of the shell. The third blocking ring, the first blocking ring, and the second blocking ring are used to increase the flow path of the working fluid inside the shell. By setting a transition component, the first blocking ring, the second blocking ring, and the third blocking ring are used to extend the flow path of the working fluid inside the shell, increasing the mixing time and mixing distance, so that the working fluid from different areas can be fully mixed, effectively reducing temperature deviation and flow deviation, and providing uniform inlet conditions for the subsequent vertical tube coil.

[0013] According to the above technical solution, inclined plates are fixedly connected to both the inner and outer sides of the second blocking ring, and a through hole is opened at the top of the first blocking ring. The inclined plates are used to disturb the flow of the working fluid inside the transition assembly. By setting the transition assembly, inclined plates are set on both the inner and outer sides of the second blocking ring, and a through hole is opened on the first blocking ring. The inclined plates are used to disturb and turn the flowing working fluid, breaking the laminar flow state. The mixing effect is further enhanced through the through hole, thereby improving the temperature and flow uniformity in the transition header.

[0014] According to the above technical solution, a cross plate is fixedly connected to the inner side of the third blocking ring. The end of the cross plate away from the third blocking ring is fixedly connected to the outer shell. The cross plate is used to disrupt the flow of the working fluid inside the transition component. By setting the transition component and the cross plate inside the third blocking ring, the working fluid is divided, turned and recombined again when it flows through the cross plate, forming a multi-stage turbulent mixing, further eliminating residual temperature stratification and concentration stratification, and making the outlet working fluid temperature distribution more uniform.

[0015] According to the above technical solution, the vertical component includes a vertical tube, the outer wall of the outer shell is connected to a second connecting ring, the top of the vertical tube is fixedly connected to the upper header, the bottom of the vertical tube is fixedly connected to the second water outlet, and a temperature measuring device is fixedly connected to the outer wall of the top of the vertical tube. The temperature measuring device is used to detect the temperature inside the vertical tube. By setting the vertical component, a movable baffle is set at the bottom of each vertical tube, and a motor drives a threaded column to move the baffle along the axis, thereby adjusting the opening area of ​​the second water inlet in real time. With the temperature measuring device set at the top of the vertical tube, the inlet flow of each vertical tube can be independently controlled according to the temperature feedback of the outlet of each vertical tube, realizing the flow distribution on demand, effectively preventing local overheating, and improving the safety and flexibility of the water-cooled wall.

[0016] According to the above technical solution, a second water inlet is provided at the bottom of the vertical pipe, and a baffle is movably connected to the inner wall of the vertical pipe. The second water inlet is used for the entry of the working medium, and the movement of the baffle can change the size of the opening of the second water inlet.

[0017] According to the above technical solution, a cavity is formed on the inner wall of the rear side of the vertical tube, a motor is fixedly connected to the outer wall of the vertical tube, a threaded column is rotatably connected to the inner wall of the cavity through a bearing, the output end of the motor is fixedly connected to the threaded column, a movable plate is fixedly connected to the top of the baffle, and the inner wall of the movable plate is threadedly connected to the threaded column, wherein the motor drives the baffle to move through the threaded column.

[0018] Compared with the prior art, the present invention provides a water-cooled wall structure for a supercritical once-through boiler, which has the following beneficial effects:

[0019] 1. By setting up transition components, the present invention extends the flow path of the working fluid inside the shell by using a first blocking ring, a second blocking ring and a third blocking ring, thereby increasing the mixing time and mixing distance, so that the working fluid from different regions can be fully mixed, effectively reducing temperature deviation and flow deviation, and providing uniform inlet conditions for subsequent vertical tube coils.

[0020] 2. The present invention sets up a transition component, with inclined plates on the inner and outer sides of the second blocking ring and through holes on the first blocking ring. The inclined plates disturb and turn the flowing working fluid, breaking the laminar flow state, and the mixing effect is further enhanced through the through holes, thereby improving the temperature and flow uniformity in the transition header.

[0021] 3. By setting a transition component and setting a cross plate inside the third blocking ring, the working fluid is divided, turned and recombined again when it flows through the cross plate, forming a multi-stage turbulent mixing, further eliminating residual temperature stratification and concentration stratification, and making the outlet working fluid temperature distribution more uniform.

[0022] 4. This invention sets up a vertical component with a movable baffle at the bottom of each vertical tube. The baffle is moved along the axis by a motor-driven threaded column, thereby adjusting the opening area of ​​the second water inlet in real time. With the help of a temperature measuring device set at the top of the vertical tube, the inlet flow of each vertical tube can be independently controlled according to the temperature feedback of the outlet of each vertical tube, so as to realize the flow distribution on demand, effectively prevent local overheating, and improve the safety and flexibility of the water-cooled wall. Attached Figure Description

[0023] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 This is a partial structural schematic diagram of the present invention;

[0026] Figure 3 Schematic diagram of the packaging mechanism of the present invention Figure 1 ;

[0027] Figure 4 Schematic diagram of the packaging mechanism of the present invention Figure 2 ;

[0028] Figure 5 Schematic diagram of the transition component of the present invention Figure 1 ;

[0029] Figure 6 Schematic diagram of the transition component of the present invention Figure 2 ;

[0030] Figure 7 Cross-sectional view of the transition component of the present invention Figure 1 ;

[0031] Figure 8 Schematic diagram of the transition component of the present invention Figure 3 ;

[0032] Figure 9 Cross-sectional view of the transition component of the present invention Figure 2 ;

[0033] Figure 10 This is a schematic diagram of the vertical component of the present invention;

[0034] Figure 11 This is a cross-sectional view of the vertical component of the present invention;

[0035] Figure 12 For the present invention Figure 11 A magnified view of A in the middle.

[0036] In the diagram: 1. First connecting ring; 101. Connecting column; 102. Connecting plate; 103. Second connecting ring; 2. Wrapping mechanism; 201. Spiral tube coil; 202. Lower header; 203. Upper header; 204. First outlet; 21. Transition assembly; 211. Outer shell; 212. Second outlet; 213. First inlet; 214. First blocking ring; 215. Second blocking ring; 216. Through hole; 217. Inclined plate; 218. Third blocking ring; 219. Cross plate; 22. Vertical assembly; 221. Vertical tube; 222. Temperature measuring device; 223. Motor; 224. Second inlet; 225. Cavity; 226. Baffle; 227. Movable plate; 228. Threaded column. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0038] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0039] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] Example 1: See Figures 1-4The present invention provides a technical solution: a supercritical once-through boiler water-cooled wall structure, including a first connecting ring 1, a connecting column 101 fixedly connected to the outer wall of the first connecting ring 1, the number of connecting columns 101 is four, a connecting plate 102 fixedly connected to the outer wall of the four connecting columns 101, and a wrapping mechanism 2 fixedly connected to the inner side of the connecting plate 102.

[0041] The packaging mechanism 2 includes: a spiral coil 201, the outer wall of which is fixedly connected to a connecting plate 102; a lower header 202 fixedly connected to the bottom of the spiral coil 201; a first outlet 204 opened at the top of the spiral coil 201; a transition component 21 fixedly connected to the top of the spiral coil 201; and a vertical component 22 fixedly connected to the top of the transition component 21. The working fluid first enters the spiral coil 201 from the lower header 202 and flows spirally upward within the spiral coil. Subsequently, the working fluid flows out from the first outlet 204 at the top of the spiral coil and enters the interior of the transition component 21 through the first inlet 213. It is fully mixed in the transition component 21 to eliminate temperature and flow deviations. The uniformly mixed working fluid enters the vertical component 22 and continues to flow upward, eventually converging at the upper header 203 for discharge.

[0042] A second connecting ring 103 is provided at the bottom of the first connecting ring 1. The outer wall of the second connecting ring 103 is fixedly connected to the connecting post 101, and the inner wall of the second connecting ring 103 is fixedly connected to the vertical component 22. The second connecting ring 103 is used to stabilize the position of the vertical component 22. An upper header 203 is fixedly connected to the top of the vertical component 22. The inner wall of the first connecting ring 1 is fixedly connected to the upper header 203. The first connecting ring 1 is used to fix the position of the upper header 203.

[0043] Example 2: Please refer to Figures 5-12Based on Embodiment 1, the present invention provides a technical solution: the transition component 21 includes a housing 211, the outer wall of which is fixedly connected to the connecting plate 102. A second outlet 212 is provided at the top of the housing 211, and a first inlet 213 is provided at the bottom of the housing 211. The bottom of the first inlet 213 is fixedly connected to a first outlet 204. The working fluid inside the spiral coil 201 enters the transition component 21 through the first outlet 204 and the first inlet 213, and finally exits from the second outlet. The working fluid is fed into the vertical assembly 22 through the inlet 212. A first blocking ring 214 is fixedly connected to the inner wall of the outer casing 211, and a second blocking ring 215 is fixedly connected to the outer wall of the first blocking ring 214. Third blocking rings 218 are fixedly connected to both the upper and lower ends of the inner wall of the outer casing 211. The third blocking ring 218, the first blocking ring 214, and the second blocking ring 215 are used to increase the flow trajectory of the working fluid inside the outer casing 211. Inclined plates 217 are fixedly connected to both the inner and outer sides of the second blocking ring 215. The first blocking ring 214... A through hole 216 is provided at the top. An inclined plate 217 is used to disrupt the flow of the working fluid inside the transition assembly 21. A cross plate 219 is fixedly connected to the inner side of the third blocking ring 218. The end of the cross plate 219 away from the third blocking ring 218 is fixedly connected to the outer shell 211. The cross plate 219 is used to disrupt the flow of the working fluid inside the transition assembly 21. The working fluid flows out from the first outlet 204 at the top of the spiral coil and enters the outer shell 211 of the transition assembly through the first inlet 213. Within 1, the working fluid first encounters the cross plate 219, which divides and deflects the working fluid, generating initial turbulence. Subsequently, the working fluid flows upward and encounters a ring-shaped channel formed by the first blocking ring 214 and the second blocking ring 215. When the working fluid flows through this structure, part of it passes through the through hole 216 at the top of the first blocking ring and goes upward, while the other part goes around the inner and outer sides of the second blocking ring. During this process, the inclined plate 217, which is fixedly connected to the inner and outer sides of the second blocking ring, further turbulents and deflects the working fluid, enhancing the mixing effect.

[0044] The vertical assembly 22 includes a vertical pipe 221, an outer wall of a housing 211 connected to a second connecting ring 103, a top of the vertical pipe 221 fixedly connected to an upper header 203, a bottom of the vertical pipe 221 fixedly connected to a second outlet 212, a temperature measuring device 222 fixedly connected to the outer wall of the top of the vertical pipe 221 for detecting the internal temperature of the vertical pipe 221, a second inlet 224 at the bottom of the vertical pipe 221, and a baffle 2 movably connected to the inner wall of the vertical pipe 221. 26, wherein the second inlet 224 is used for the entry of the working medium, and the movement of the baffle 226 can change the size of the opening of the second inlet 224. A cavity 225 is opened on the inner wall of the rear side of the vertical pipe 221. A motor 223 is fixedly connected to the outer wall of the vertical pipe 221. A threaded column 228 is rotatably connected to the inner wall of the cavity 225 through a bearing. The output end of the motor 223 is fixedly connected to the threaded column 228. A movable plate 227 is fixedly connected to the top of the baffle 226. The inner wall of the movable plate 227 is connected to the threaded column 228. The column 228 is threaded, wherein the motor 223 drives the baffle 226 to move through the threaded column 228; the working fluid flows out from the second outlet 212 of the transition component, enters the interior of the vertical pipe 221 through the second inlet 224 at the bottom of the vertical pipe, flows from bottom to top, and finally flows into the upper header 203; a temperature measuring device 222 is provided on the outer wall of the top of each vertical pipe 221 to detect the working fluid temperature at the outlet of the vertical pipe; when the temperature measuring device detects an abnormal increase in the outlet temperature of a certain vertical pipe, it indicates If the flow rate of the pipe is insufficient or the heat load is too high, the motor 223 will start and its output end will drive the threaded column 228 to rotate in the cavity 225, thereby driving the baffle 226 to move. When the baffle 226 moves, it will change the opening area of ​​the second inlet 224. When the flow rate needs to be increased, the motor 223 will drive the baffle 226 to move backward, so that the opening of the second inlet 224 will be increased. When the flow rate needs to be reduced, the motor 223 will drive the baffle 226 to move inward, so that the opening of the second inlet 224 will be reduced.

[0045] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0046] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A supercritical once-through boiler water wall structure, comprising a first connecting ring (1), an outer wall of the first connecting ring (1) is fixedly connected with connecting columns (101), the number of the connecting columns (101) is four, outer walls of the four connecting columns (101) are fixedly connected with connecting plates (102), characterized in that, The inner side of the connecting plate (102) is fixedly connected to the wrapping mechanism (2); The parcel mechanism (2) includes; A spiral tube coil (201) is fixedly connected to a connecting plate (102) on its outer wall. A lower header (202) is fixedly connected to the bottom of the spiral tube coil (201). A first outlet (204) is opened on the top of the spiral tube coil (201). A transition component (21) is fixedly connected to the top of the spiral tube coil (201). A vertical component (22) is fixedly connected to the top of the transition component (21).

2. A supercritical once-through boiler waterwall structure according to claim 1, characterized in that: The bottom of the first connecting ring (1) is provided with a second connecting ring (103). The outer wall of the second connecting ring (103) is fixedly connected to the connecting column (101), and the inner wall of the second connecting ring (103) is fixedly connected to the vertical component (22). The second connecting ring (103) is used to stabilize the position of the vertical component (22).

3. A supercritical once-through boiler waterwall structure according to claim 2, characterized in that: The top of the vertical component (22) is fixedly connected to the upper header (203), and the inner wall of the first connecting ring (1) is fixedly connected to the upper header (203). The first connecting ring (1) is used to fix the position of the upper header (203).

4. A supercritical once-through boiler waterwall structure according to claim 3, characterized in that: The transition component (21) includes a shell (211), the outer wall of which is fixedly connected to the connecting plate (102). The top of the shell (211) is provided with a second outlet (212), and the bottom of the shell (211) is provided with a first inlet (213). The bottom of the first inlet (213) is fixedly connected to the first outlet (204). The working fluid inside the spiral coil (201) enters the transition component (21) through the first outlet (204) and the first inlet (213), and is finally sent into the vertical component (22) from the second outlet (212).

5. The water-cooled wall structure of a supercritical once-through boiler according to claim 4, characterized in that: The inner wall of the outer shell (211) is fixedly connected to a first blocking ring (214), the outer wall of the first blocking ring (214) is fixedly connected to a second blocking ring (215), and the upper and lower ends of the inner wall of the outer shell (211) are fixedly connected to a third blocking ring (218). The third blocking ring (218), the first blocking ring (214), and the second blocking ring (215) are used to increase the flow trajectory of the working fluid inside the outer shell (211).

6. The water-cooled wall structure of a supercritical once-through boiler according to claim 5, characterized in that: The second blocking ring (215) has inclined plates (217) fixedly connected to both its inner and outer sides. The first blocking ring (214) has a through hole (216) at its top. The inclined plates (217) are used to disrupt the flow of the working fluid inside the transition assembly (21).

7. The water-cooled wall structure of a supercritical once-through boiler according to claim 6, characterized in that: A cross plate (219) is fixedly connected to the inner side of the third blocking ring (218). The end of the cross plate (219) away from the third blocking ring (218) is fixedly connected to the outer shell (211). The cross plate (219) is used to disrupt the flow of the working fluid inside the transition assembly (21).

8. The water-cooled wall structure of a supercritical once-through boiler according to claim 7, characterized in that: The vertical assembly (22) includes a vertical tube (221), the outer wall of the outer shell (211) is connected to a second connecting ring (103), the top of the vertical tube (221) is fixedly connected to the upper header (203), the bottom of the vertical tube (221) is fixedly connected to the second outlet (212), and a temperature measuring device (222) is fixedly connected to the outer wall of the top of the vertical tube (221), wherein the temperature measuring device (222) is used to detect the temperature inside the vertical tube (221).

9. The water-cooled wall structure of a supercritical once-through boiler according to claim 8, characterized in that: The bottom of the vertical pipe (221) is provided with a second water inlet (224), and the inner wall of the vertical pipe (221) is movably connected with a baffle (226). The second water inlet (224) is used for the entry of the working medium, and the movement of the baffle (226) can change the size of the opening of the second water inlet (224).

10. The water-cooled wall structure of a supercritical once-through boiler according to claim 9, characterized in that: A cavity (225) is provided on the inner wall of the rear side of the vertical tube (221). A motor (223) is fixedly connected to the outer wall of the vertical tube (221). A threaded column (228) is rotatably connected to the inner wall of the cavity (225) through a bearing. The output end of the motor (223) is fixedly connected to the threaded column (228). A movable plate (227) is fixedly connected to the top of the baffle (226). The inner wall of the movable plate (227) is threadedly connected to the threaded column (228). The motor (223) drives the baffle (226) to move through the threaded column (228).

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