New desuperheating water system for superheater and reheater of million-ton tower boiler

Abstract

The present invention relates to a desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler. At present, in order to ensure the wall temperature safety of the reheater system, the desuperheating water of the reheater is often put into use, and the input of the desuperheating water of the reheater will reduce the efficiency of the boiler, thus ultimately affecting the coal consumption of the unit and increasing the operation cost of the power plant. A desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler includes: a feed water pump (1), the feed water pump is connected to a group of high-temperature heaters (2), the group of high-temperature heaters are connected in series on the pipeline of the feed water pump, the group of high-temperature heaters are connected to the boiler feed water system, a superheater desuperheating water main pipe (3) is connected between the boiler feed water system and the group of high-temperature heaters, and the superheater desuperheating water main pipe is connected to a primary desuperheating water branch (11) and a secondary desuperheating water branch (12). The present invention is applied to the field of boilers.

Description

Technical Field

[0001] The present invention relates to a desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler. Background Art

[0002] At present, with the successive commissioning of high-efficiency ultra-supercritical boilers, the phenomenon of over-temperature bursting of high-temperature heating surfaces of superheaters and reheaters has occurred in many power plants. In order to control the over-temperature of the heating surface tube screens, a large amount of desuperheating water is sprayed in the actual operation of both the superheater desuperheating water and the reheater desuperheating water. However, when the boiler is designed, the reheater desuperheating water does not need to be put into operation. If a large amount of reheater desuperheating water is used during actual operation, it will inevitably reduce the boiler efficiency and increase the actual coal consumption on site. The desuperheating water systems of the superheaters and reheaters of all coal-fired units are divided into two paths. At the same time, the superheater desuperheating water is taken from the inlet of the economizer, and the reheater desuperheating water is taken from the intermediate tap of the feed water pump. With the rapid development of ultra (ultra)-critical power technology in the past 20 years, the boiler outlet parameters are getting higher and higher. Especially, the reheater steam has developed to the high-efficiency parameter stage of 623 °C. From the operation data of the actual commissioning at 623 °C, in order to ensure the wall temperature safety of the reheater system, the reheater desuperheating water is often put into operation, and the input of the reheater desuperheating water will reduce the boiler efficiency, thus ultimately affecting the coal consumption of the unit and increasing the operation cost of the power plant. Summary of the Invention

[0003] The purpose of the present invention is to provide a desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler, which solves the problem of affecting the boiler efficiency due to the input of the reheater desuperheating water and can improve the economic indexes of the whole power plant.

[0004] The above purpose is achieved by the following technical solutions:

[0005] A desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler, comprising: a feed water pump, the feed water pump is connected to a group of high-temperature heaters, a group of the high-temperature heaters are connected in series on the pipeline of the feed water pump, a group of the high-temperature heaters are connected to the boiler feed water system, a desuperheating water main pipe for the superheater is connected between the boiler feed water system and a group of the high-temperature heaters, the desuperheating water main pipe for the superheater is connected to a primary desuperheating water branch and a secondary desuperheating water branch, one end of the desuperheating water main pipe for the superheater is connected to a desuperheating and pressure-reducing device, the other end of the desuperheating and pressure-reducing device is connected to a desuperheating water main pipe for the reheater, and the desuperheating water main pipe for the reheater is connected to a desuperheating water branch for the reheater.

[0006] In the desuperheating water system for superheaters and reheaters of the new type of million-ton tower boiler, the primary desuperheating water branch is connected to a primary superheater desuperheater, and the primary superheater desuperheater is respectively connected to a primary superheater outlet header and a secondary superheater inlet header.

[0007] For the desuperheating water system of the superheater and reheater of the new million-ton tower boiler, the secondary desuperheating water branch is connected to the secondary superheater desuperheater, and the secondary superheater desuperheater is respectively connected to the secondary superheater outlet header and the tertiary superheater inlet header.

[0008] For the desuperheating water system of the superheater and reheater of the new million-ton tower boiler, the secondary superheater inlet header is connected to the secondary superheater outlet header through the secondary superheater, and the tertiary superheater inlet header is connected to the tertiary superheater outlet header through the tertiary superheater.

[0009] For the desuperheating water system of the superheater and reheater of the new million-ton tower boiler, the desuperheating water branch of the reheater is connected to the desuperheater of the reheater, and the desuperheater of the reheater is respectively connected to the first-stage reheater outlet header and the second-stage reheater inlet header.

[0010] For the desuperheating water system of the superheater and reheater of the new million-ton tower boiler, the first-stage reheater outlet header is connected to the first-stage reheater inlet header through the first-stage reheater, and the second-stage reheater inlet header is connected to the second-stage reheater outlet header through the second-stage reheater.

[0011] Advantages of the present invention:

[0012] 1. The present invention overcomes the deficiencies of the prior art, solves the problem of reducing the boiler efficiency due to the injection of desuperheating water for the reheater at present, and can improve the economic indicators of the entire power plant.

[0013] The present invention is composed of a feed pump high-pressure heater system, a primary superheater desuperheating water pipeline system, a secondary superheater desuperheating water pipeline system, and a reheater desuperheating water pipeline system.

[0014] (1) The feed pump high-pressure heater system is a boiler feed water heating system, mainly including a feed pump and a high-temperature heater (high-pressure heater), and also includes relevant connecting pipelines.

[0015] (2) The primary superheater desuperheating water pipeline system is mainly used to cool the steam temperature at the outlet of the primary superheater during the operation of the boiler, and control the temperature of the secondary superheater tube bank not to exceed the limit.

[0016] (3) The secondary superheater desuperheating water pipeline system is mainly used to cool the steam temperature at the outlet of the secondary superheater during the operation of the boiler, and control the temperature of the tertiary superheater tube bank not to exceed the limit.

[0017] (4) The reheater desuperheating water pipeline system is mainly used to cool the steam temperature at the outlet of the first-stage reheater during the operation of the boiler, and control the temperature of the second-stage reheater tube bank not to exceed the limit. Description of the Drawings

[0018] Appendix Figure 1 is the structural schematic diagram of the present invention.

[0019] Appendix Figure 2 is the original structural schematic diagram of Appendix Figure 1 .

[0020] In the figure: 1, feed water pump; 2, high-temperature heater; 3, main header of desuperheating water for superheater; 5, desuperheater for primary superheater; 6, desuperheater for secondary superheater; 7, main header of desuperheating water for reheater; 9, desuperheater for reheater; 10, attemperating and pressure-reducing device; 11, primary desuperheating water branch; 12, secondary desuperheating water branch; 13, outlet header of primary superheater; 14, inlet header of secondary superheater; 15, inlet header of tertiary superheater; 16, outlet header of tertiary superheater; 17, outlet header of primary reheater; 18, inlet header of primary reheater; 19, inlet header of secondary reheater; 20, outlet header of secondary reheater; 21, outlet header of secondary superheater; 22, desuperheating water branch for reheater. Detailed implementation manners

[0021] Example 1:

[0022] A novel desuperheating water system for superheater and reheater of a million-ton tower boiler, comprising: a feed water pump 1, the feed water pump is connected to a group of high-temperature heaters 2, the group of high-temperature heaters are connected in series on the pipeline of the feed water pump, the group of high-temperature heaters are connected to the boiler feed water system, a main header of desuperheating water for superheater 3 is connected between the boiler feed water system and the group of high-temperature heaters, the main header of desuperheating water for superheater is connected to a primary desuperheating water branch 11 and a secondary desuperheating water branch 12, one end of the main header of desuperheating water for superheater is connected to an attemperating and pressure-reducing device 10, the other end of the attemperating and pressure-reducing device is connected to a main header of desuperheating water for reheater 7, and the main header of desuperheating water for reheater is connected to a desuperheating water branch 22 for reheater.

[0023] Example 2:

[0024] For the novel desuperheating water system for superheater and reheater of a million-ton tower boiler according to Example 1, the primary desuperheating water branch is connected to a desuperheater 5 for primary superheater, and the desuperheater for primary superheater is respectively connected to an outlet header 13 of primary superheater and an inlet header 14 of secondary superheater.

[0025] Example 3:

[0026] For the novel desuperheating water system for superheater and reheater of a million-ton tower boiler according to Example 1 or 2, the secondary desuperheating water branch is connected to a desuperheater 6 for secondary superheater, and the desuperheater for secondary superheater is respectively connected to an outlet header 21 of secondary superheater and an inlet header 15 of tertiary superheater.

[0027] Example 4:

[0028] The desuperheating water system for the superheater and reheater of the new million-ton tower boiler according to Embodiment 1 or 2 or 3, wherein the inlet header of the secondary superheater is connected to the outlet header of the secondary superheater through the secondary superheater, and the inlet header of the tertiary superheater is connected to the outlet header 16 of the tertiary superheater.

[0029] Embodiment 5:

[0030] The desuperheating water system for the superheater and reheater of the new million-ton tower boiler according to Embodiment 1 or 2 or 3 or 4, wherein the desuperheating water branch of the reheater is connected to the desuperheater 9 of the reheater, and the desuperheater of the reheater is respectively connected to the outlet header 17 of the primary reheater and the inlet header 19 of the secondary reheater.

[0031] Embodiment 6:

[0032] The desuperheating water system for the superheater and reheater of the new million-ton tower boiler according to Embodiment 1 or 2 or 3 or 4 or 5, wherein the outlet header of the primary reheater is connected to the inlet header 18 of the primary reheater through the primary reheater, and the inlet header of the secondary reheater is connected to the outlet header 20 of the secondary reheater through the secondary reheater.

[0033] Embodiment 7:

[0034] As Figure 1 shown, the feed water heating system in the desuperheating water system for the superheater and reheater of the new million-ton tower boiler includes: a feed water pump, a high-temperature heater, and connecting pipes between related equipment.

[0035] The main desuperheating water pipe for the superheater, the desuperheating water branch pipe for the superheater, the primary desuperheater for the superheater, the secondary desuperheater for the superheater, and connecting pipes between related equipment.

[0036] The main desuperheating water pipe for the reheater, the desuperheating water branch pipe for the reheater, the desuperheater for the reheater, the desuperheating and pressure-reducing device, and connecting pipes between related equipment.

Claims

1. A new attemperating water system for the superheater and reheater of a million-ton tower boiler, which comprises: Feed water pump, high-temperature heater, connecting pipe, desuperheater, header, characterized in that: the feed water pump is connected to a group of high-temperature heaters, a group of the high-temperature heaters are connected in series on the pipeline of the feed water pump, a group of the high-temperature heaters are connected to the boiler feed water system, a desuperheated steam desuperheating water main pipe is connected between the boiler feed water system and a group of the high-temperature heaters, the desuperheated steam desuperheating water main pipe is connected to a primary desuperheating water branch and a secondary desuperheating water branch, one end of the desuperheated steam desuperheating water main pipe is connected to a desuperheating and pressure-reducing device, the other end of the desuperheating and pressure-reducing device is connected to the desuperheating water main pipe of the reheater, the desuperheating water main pipe of the reheater is connected to the desuperheating water branch of the reheater, and the feed water pump high-pressure heater system is a boiler feed water heating system, mainly including a feed water pump and a high-temperature heater, and also includes relevant connecting pipelines in addition.

2. The attemperating water system for the superheater and reheater of the novel million-tower boiler according to claim 1, characterized in that: The primary desuperheating water branch is connected to the primary superheater desuperheater, and the primary superheater desuperheater is respectively connected to the primary superheater outlet header and the secondary superheater inlet header.

3. The attemperating water system for superheater and reheater of the new million-tower boiler according to claim 2, characterized in that: The secondary desuperheating water branch is connected to the secondary superheater desuperheater, and the secondary superheater desuperheater is respectively connected to the secondary superheater outlet header and the tertiary superheater inlet header.

4. The desuperheating water system for the superheater and reheater of the new million-tower boiler according to claim 3, characterized in that: The secondary superheater inlet header and the secondary superheater outlet header are connected by a secondary superheater, and the tertiary superheater inlet header and the tertiary superheater outlet header are connected by a tertiary superheater.

5. The desuperheating water system for the superheater and reheater of the new million-tower boiler according to claim 1, characterized in that: The desuperheating water branch of the reheater is connected to the desuperheater of the reheater, and the desuperheater of the reheater is respectively connected to the primary reheater outlet header and the secondary reheater inlet header.

6. The desuperheating water system for the superheater and reheater of the novel million-tower boiler according to claim 5, characterized in that: The primary reheater outlet header and the primary reheater inlet header are connected by a primary reheater, and the secondary reheater inlet header and the secondary reheater outlet header are connected by a secondary reheater.

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