Double-medium hanging pipe structure for deep peak shaving tower type boiler

Abstract

The invention discloses a double-medium hanging pipe structure for a deep peak shaving tower type boiler, belongs to the technical field of coal-fired power generation boilers, and aims to solve the problems that under the working condition of long-time wet operation, the cooling capacity of an existing hanging pipe structure is seriously insufficient, the risk of pipe explosion and shutdown exists, and safe and stable operation of a unit is seriously affected. The device comprises a separator, a separator outlet connecting pipe, a separator inlet connecting pipe, a superheater, a water cooling wall and a plurality of in-furnace hanging pipe panels, the water cooling wall is communicated with the in-furnace hanging pipe panels, and the in-furnace hanging pipe panels are communicated with the separator through the separator inlet connecting pipe. The separator is communicated with the superheater through a separator outlet connecting pipe, steam-water double media discharged by the water cooling wall pass through a plurality of in-furnace hanging pipe panels from bottom to top, then enter the separator and are subjected to steam-water separation in the separator, and then steam media enter the superheater. The hanging pipe structure is mainly used as the hanging pipe structure of the deep peak shaving tower type boiler.

Description

Technical Field

[0001] The invention belongs to the technical field of coal-fired power generation boilers, and in particular relates to a dual-medium hanging pipe structure for a deep peak-shaving tower boiler. Background Art

[0002] Since tower boilers have certain advantages over Π-type boilers in terms of heating surface deviation control, with the improvement of unit parameters, more and more high-efficiency ultra-supercritical units are using tower layout. The heating surfaces of tower-type boilers are all arranged horizontally, and the hanging pipes in the furnace string all the heating surfaces together from top to bottom for hanging. Therefore, the safety of the hanging pipes of tower boilers has become the focus of the entire boiler design.

[0003] The existing hanging pipe structure and process uses superheated steam from the separator outlet to cool the medium in the pipe. The function of the separator is to separate the steam-water dual medium into steam and water. The steam from the separator enters the superheater, and the separated water re-enters the water supply pipe by starting the circulating pump. When the unit is running in the wet state, the dryness of the steam is relatively low, and the separator contains the dual medium of steam and water. The steam separated by the separator enters the hanging pipe. The amount of this part of steam is small, not the full flow of steam and water, and the cooling capacity of the hanging pipe is relatively weak. The load conditions of the existing units are all in dry operation, and the wet condition is basically the starting condition, which passes quickly in actual operation and the time is relatively short. Although the cooling capacity of the hanging pipe is relatively weak, the time is relatively short, and the safety hazard of the hanging pipe is relatively small at this time.

[0004] As the deep peak load of the unit decreases, the boiler will have to operate in a wet state for a long time. Under this condition, the existing hanging pipe structure causes the steam flow rate in the pipe to decrease sharply, and the cooling capacity of the hanging pipe is seriously insufficient, which poses the risk of pipe explosion and shutdown, seriously affecting the safe and stable operation of the unit.

[0005] In addition, the existing hanging pipes all adopt a top-down flow mode, and large pipes are used outside the furnace to connect with the low-temperature superheater. The large pipes are heavy, resulting in high boiler costs and weak market competitiveness. Summary of the invention

[0006] The present invention aims to solve the problem that the cooling capacity of the existing hanging pipe structure is seriously insufficient under the condition of long-term wet operation, there is a risk of pipe bursting and shutdown, which seriously affects the safe and stable operation of the unit, and the existing hanging pipes all adopt a top-down flow mode, so that a large pipeline outside the furnace needs to be connected to the low-temperature superheater, resulting in a high boiler cost; and further provide a dual-medium hanging pipe structure for a deep peak-shaving tower boiler;

[0007] A dual-medium hanging pipe structure for a deep peak-shaving tower boiler, the dual-medium hanging pipe structure comprising a separator, a separator outlet connecting pipe, a separator inlet connecting pipe, a superheater, a water-cooled wall and a plurality of in-furnace hanging pipes and tube panels, the water-cooled wall and the plurality of in-furnace hanging pipes and tube panels are all connected, the plurality of in-furnace hanging pipes and tube panels are all connected with the separator through the separator inlet connecting pipe, the separator is connected with the superheater through the separator outlet connecting pipe, the steam-water dual medium discharged from the water-cooled wall passes through the plurality of in-furnace hanging pipes and tube panels from bottom to top and enters the separator, and after steam-water separation is performed in the separator, the steam medium enters the superheater;

[0008] Further, the superheater is a low temperature superheater;

[0009] Furthermore, a water-cooled wall intermediate header is provided at the inlet end of the water-cooled wall, and the water-cooled wall and the water-cooled wall intermediate header are connected;

[0010] Furthermore, a water-cooled wall outlet header is provided at the outlet end of the water-cooled wall, and the water-cooled wall and the water-cooled wall outlet header are connected to each other;

[0011] Furthermore, a plurality of hanging tube panels in the furnace are arranged in sequence and equidistantly along the extension direction of the water-cooled wall outlet header;

[0012] Furthermore, each furnace hanging tube panel includes a plurality of furnace hanging tubes, and the plurality of furnace hanging tubes are arranged in sequence and equidistantly along the extension direction of the water wall outlet header;

[0013] Furthermore, the dual-medium hanging pipe structure also includes a hanging pipe upper header, and the outlet ends of the plurality of hanging pipe panels in the furnace are connected to the separator inlet connecting pipe through the hanging pipe upper header;

[0014] Furthermore, a hanging pipe lower header is provided at the inlet end of each hanging pipe panel in the furnace, and each hanging pipe panel in the furnace is connected to the hanging pipe lower header;

[0015] Furthermore, a suspension pipe is provided between each suspension pipe lower header and the water-cooled wall outlet header, and each suspension pipe lower header is connected to the water-cooled wall outlet header via a suspension pipe.

[0016] The beneficial effects of this application compared to the prior art are as follows:

[0017] 1. The dual-medium hanging pipe structure for deep peak-shaving tower boilers provided in the present application has readjusted the steam flow compared to the traditional hanging pipe structure, and uses the medium at the outlet of the water-cooled wall for cooling, and the working medium in the hanging pipe flows from bottom to top. During long-term wet operation of deep peak-shaving, the outlet of the water-cooled wall is a dual medium of steam and water. On the one hand, since the working medium in the hanging pipe does not pass through the separator, the cooling flow is the full flow of steam and water, which is a significant increase compared to the existing structure. On the other hand, the cooling capacity of the dual medium of steam and water is also greatly improved compared to the existing superheated steam. This ensures the safety of the hanging pipe, while simplifying the entire steam-water process and reducing the steam-water resistance of the entire system.

[0018] 2. The present application provides a dual-medium hanging pipe structure for a deep peak-shaving tower boiler, in which the water-cooled wall outlet header directly enters the hanging pipe and its tube screen at the outlet of the lower furnace through the hanging pipe outside the furnace, then flows from bottom to top along the hanging pipe, and finally enters the separator through the hanging pipe upper header arranged on the furnace top. After the separator, it enters the low-temperature superheater through the separator outlet pipe, reducing the weight of the large pipe outside the furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural schematic diagram of a dual-medium hanging pipe structure for a deep peak-shaving tower boiler described in this application;

[0020] In the figure, 1 is a separator, 2 is a separator outlet connecting pipe, 3 is a hanging pipe upper header, 4 is a furnace hanging pipe, 5 is a hanging pipe lower header, 6 is a separator inlet connecting pipe, 7 is a water-cooled wall intermediate header, 8 is a hanging pipe, 9 is a water-cooled wall outlet header, 10 is a superheater and 11 is a water-cooled wall. DETAILED DESCRIPTION

[0021] Specific implementation method 1: Combination Figure 1 The present embodiment is described. In the present embodiment, a dual-medium hanging pipe structure for a deep peak-shaving tower boiler is provided, which is characterized in that: the dual-medium hanging pipe structure includes a separator 1, a separator outlet connecting pipe 2, a separator inlet connecting pipe 6, a superheater 10, a water-cooled wall 11 and a plurality of in-furnace hanging pipes and tube panels, the water-cooled wall 11 and the plurality of in-furnace hanging pipes and tube panels are all connected, the plurality of in-furnace hanging pipes and tube panels are all connected to the separator 1 through the separator inlet connecting pipe 6, the separator 1 is connected to the superheater 10 through the separator outlet connecting pipe 2, the steam-water dual medium discharged from the water-cooled wall 11 passes through the plurality of in-furnace hanging pipes and tube panels from bottom to top and enters the separator 1, and after steam-water separation is performed in the separator 1, the steam medium enters the superheater 10.

[0022] A dual-medium hanging pipe structure for a deep peak-shaving tower boiler provided in the present embodiment changes the medium form in the hanging pipe compared to the traditional hanging pipe structure, optimizing the traditional vapor medium to a steam-water dual medium, and optimizing the medium flow. After the optimization of the present application, since the working fluid in the hanging pipe does not pass through the separator, the cooling flow is the full flow of steam and water, which is greatly increased compared to the existing structure, and the cooling capacity of the steam-water dual medium is also greatly improved compared to the existing superheated steam, thereby ensuring the safety of the hanging pipe, simplifying the entire steam-water process, and reducing the steam-water resistance of the entire system.

[0023] Specific implementation method 2: Combination Figure 1 This embodiment is described. The difference between this embodiment and the first embodiment is that the superheater 10 is a low-temperature superheater. The other components and connection methods are the same as those of the first embodiment.

[0024] Specific implementation method three: Combination Figure 1 This embodiment is described. The difference between this embodiment and the second embodiment is that a water-cooled wall intermediate header 7 is provided at the inlet end of the water-cooled wall 11, and the water-cooled wall 11 is connected to the water-cooled wall intermediate header 7. Other components and connection methods are the same as those of the second embodiment.

[0025] Specific implementation method four: Combination Figure 1 This embodiment is described. The difference between this embodiment and the third embodiment is that a water wall outlet header 9 is provided at the outlet end of the water wall 11, and the water wall 11 is connected to the water wall outlet header 9. Other components and connection methods are the same as those of the third embodiment.

[0026] Specific implementation method five: Combination Figure 1 This embodiment is described. The difference between this embodiment and the fourth embodiment is that a plurality of in-furnace hanging tube panels are arranged in sequence and equidistantly along the extension direction of the water-cooled wall outlet header 9. Other components and connection methods are the same as those of the fourth embodiment.

[0027] Specific implementation method six: Combination Figure 1 This embodiment is described. The difference between this embodiment and the fifth embodiment is that each furnace hanging tube panel includes a plurality of furnace hanging tubes 4, and the plurality of furnace hanging tubes 4 are arranged in sequence and equidistantly along the extension direction of the water wall outlet header 9. The other components and connection methods are the same as those of the fifth embodiment.

[0028] Specific implementation method seven: Combination Figure 1This embodiment is described. The difference between this embodiment and the specific embodiment 6 is that the dual-medium hanging pipe structure further includes a hanging pipe upper header 3, and the outlet ends of the multiple hanging pipe panels in the furnace are connected to the separator inlet connecting pipe 6 through the hanging pipe upper header 3. The other components and connection methods are the same as those of the specific embodiment 7.

[0029] Specific implementation method eight: Combination Figure 1 This embodiment is described. The difference between this embodiment and the seventh embodiment is that a hanging tube lower header 5 is provided at the inlet end of each furnace hanging tube panel, and each furnace hanging tube panel is connected to the hanging tube lower header 5. Other components and connection methods are the same as those of the eighth embodiment.

[0030] Specific implementation method nine: Combination Figure 1 This embodiment is described. The difference between this embodiment and the eighth embodiment is that a suspension pipe 8 is provided between each suspension pipe lower header 5 and the water-cooled wall outlet header 9, and each suspension pipe lower header 5 is connected to the water-cooled wall outlet header 9 through a suspension pipe 8. Other components and connection methods are the same as those of the ninth embodiment.

[0031] In this embodiment, the steam-water dual medium passes through the water-cooled wall outlet header 9 and directly enters the hanging pipe lower header 5 through the furnace external hanging pipe 8, which can effectively reduce the weight of the large pipeline outside the furnace.

[0032] The present invention has been disclosed as above with preferred implementation cases, but it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent implementation cases with equivalent changes by using the above-disclosed structures and technical contents without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above implementation cases based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

[0033] How it works

[0034] When the present application is working, the steam-water dual medium process first passes through the water-cooled wall intermediate header 7 into the water-cooled wall 11, and passes through the water-cooled wall 11 from bottom to top and then enters the water-cooled wall outlet header 9. Since the water-cooled wall outlet header 9 and the hanging tube lower header 5 are connected through the hanging tube 8, the steam-water dual medium will directly pass through the water-cooled wall outlet header 9 through the hanging tube 8 and enter the hanging tube lower header 5, and continue to pass through the furnace hanging tube 4 from bottom to top and then enter the hanging tube upper header 3. The hanging tube upper header 3 introduces the steam-water dual medium into the separator 1 through the separator inlet connecting pipe 6. At this time, the steam-water dual medium is separated into gas and liquid in the separator 1, and the separated gas medium enters the superheater 10 along the separator outlet connecting pipe 2, completing the medium process in the present application.

[0035] Based on the optimization of the medium form, hanging pipe structure and medium flow in this application, the cooling flow and cooling capacity under deep peak-shaving wet operation can be effectively increased, the safety of the hanging pipes can be ensured, and at the same time the entire steam-water flow is simplified, and the steam-water resistance of the entire system is reduced. In addition, the structure and process developed this time reduce the traditional superheater inlet connecting pipe, that is, reduce the weight of the large pipeline outside the furnace, which is conducive to saving the manufacturing cost of the structure.

Claims

1. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler, characterized in that: The dual-medium hanging pipe structure comprises a separator (1), a separator outlet connecting pipe (2), a separator inlet connecting pipe (6), a superheater (10), a water-cooled wall (11) and a plurality of in-furnace hanging pipe panels. The water-cooled wall (11) and the plurality of in-furnace hanging pipe panels are connected. The plurality of in-furnace hanging pipe panels are connected to the separator (1) through the separator inlet connecting pipe (6). The separator (1) is connected to the superheater (10) through the separator outlet connecting pipe (2). The steam-water dual medium discharged from the water-cooled wall (11) passes through the plurality of in-furnace hanging pipe panels from bottom to top and enters the separator (1). After steam and water are separated in the separator (1), the steam medium enters the superheater (10).

2. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 1, characterized in that: The superheater (10) is a low-temperature superheater.

3. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 2, characterized in that: A water-cooled wall intermediate header (7) is provided at the inlet end of the water-cooled wall (11), and the water-cooled wall (11) and the water-cooled wall intermediate header (7) are connected.

4. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 3, characterized in that: A water-cooled wall outlet header (9) is provided at the outlet end of the water-cooled wall (11), and the water-cooled wall (11) is connected to the water-cooled wall outlet header (9).

5. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 4, characterized in that: A plurality of in-furnace hanging tube panels are arranged in sequence and at equal intervals along the extension direction of the water-cooled wall outlet header (9).

6. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 5, characterized in that: Each furnace hanging tube panel includes a plurality of furnace hanging tubes (4), and the plurality of furnace hanging tubes (4) are arranged in sequence and at equal distances along the extension direction of the water-cooled wall outlet header (9).

7. The dual-medium hanging pipe structure for deep peak-shaving tower boiler according to claim 1, characterized in that: The dual-medium hanging pipe structure also includes a hanging pipe upper header (3), and the outlet ends of the plurality of hanging pipe panels in the furnace are connected to the separator inlet connecting pipe (6) through the hanging pipe upper header (3).

8. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 7, characterized in that: A hanging pipe lower header (5) is provided at the inlet end of each hanging pipe panel in the furnace, and each hanging pipe panel in the furnace is connected to the hanging pipe lower header (5).

9. A dual-medium hanging pipe structure for a deep peak-shaving tower boiler according to claim 8, characterized in that: A suspension pipe (8) is provided between each suspension pipe lower header (5) and the water-cooled wall outlet header (9), and each suspension pipe lower header (5) is connected to the water-cooled wall outlet header (9) via a suspension pipe (8).

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