Electric precipitation steam air heater

Abstract

The utility model discloses an electric dust removal steam air heater, which relates to the technical field of electric dust removers of thermal power plants, and comprises a steam main pipe, an air inlet of the steam main pipe is connected with a cold reheat steam source of the thermal power plant, the steam main pipe is connected with a plurality of steam branch pipes, and each steam branch pipe is connected with a steam heater; a drain pipe of the steam heater is connected into a soot blower of a selective catalytic reduction reaction area of the thermal power plant; the device further comprises a blowing air main pipe, one end of the blowing air main pipe is connected with the draught fan, the blowing air main pipe is connected with a plurality of blowing air branch pipes, and each blowing air branch pipe is connected with an air inlet of one steam heater. And a plurality of porcelain bushing heating air pipes are arranged at an air outlet of the steam heater, are connected into a dust removal chamber of the electric dust remover and are used for blowing insulating porcelain bushings of all electric fields in the dust removal chamber with hot air. According to the utility model, the technical problems of insufficient capacity, unstable electric field operation and high maintenance cost in the prior art are solved.

Description

An electrostatic precipitator steam heater Technical Field

[0001] This utility model relates to the technical field of electrostatic precipitators for thermal power plants, specifically an electrostatic precipitator steam heater. Background Technology

[0002] In existing electrostatic precipitators in thermal power plants, the insulated porcelain bushing purging air system typically uses electric heating to heat the purging air to prevent electric field flashover caused by low-temperature condensation or dirt on the insulators. However, with the commissioning of the denitrification system, the capacity of the original electric heaters is insufficient to meet the heating requirements, leading to the following problems: Insufficient electric heater capacity: the purging air temperature cannot stably reach above 140℃, and dust or condensation easily accumulates on the insulator surface, causing electric field flashover; Unstable electric field operation: the electric field frequently reduces output or shuts down, affecting dust removal efficiency; High maintenance costs: frequent cleaning of dirty insulators is required, increasing labor and downtime costs. Summary of the Invention

[0003] The purpose of this utility model is to provide an electrostatic precipitator steam heater in order to solve at least one of the above-mentioned technical problems.

[0004] In a first aspect, this utility model provides an electrostatic precipitator steam heater, comprising: a steam main pipe, the inlet of which is connected to a cold reheat steam source of a thermal power plant, and multiple steam branch pipes connected to the steam main pipe, each steam branch pipe being connected to a steam heater; the drain pipe of the steam heater being connected to a soot blower in the selective catalytic reduction reaction zone of the thermal power plant; and a purge air main pipe, one end of which is connected to a fan, and multiple purge air branch pipes connected to the purge air main pipe, each purge air branch pipe being connected to an inlet of the steam heater; and multiple porcelain sleeve heating air pipes being provided at the outlet of the steam heater, the multiple porcelain sleeve heating air pipes being connected to the dust removal chamber of the electrostatic precipitator for hot air purging of the insulating porcelain sleeves of each electric field in the dust removal chamber.

[0005] Furthermore, a first steam inlet shut-off valve and a second steam inlet shut-off valve are sequentially installed on the steam branch pipe; a first drain shut-off valve and a second drain shut-off valve are sequentially installed on the drain pipe; and a duct shut-off valve is installed on the ceramic sleeve heating air duct.

[0006] Furthermore, the first steam inlet shut-off valve and the second steam inlet shut-off valve include DN40 shut-off valves; the first drain shut-off valve and the second drain shut-off valve include DN32 shut-off valves; and the duct shut-off valve includes DN50 shut-off valves.

[0007] Furthermore, a temperature sensor and a pressure sensor are also provided at the connection between the steam branch pipe and the steam heater; the temperature sensor is used to monitor the inlet temperature of the steam heater; the pressure sensor is used to monitor the inlet pressure of the steam heater.

[0008] Furthermore, the temperature sensor includes a bimetallic thermometer.

[0009] Furthermore, a manual drain valve and an electric drain valve are sequentially installed on the steam header near the outlet.

[0010] Furthermore, a check valve is installed on the purge air main pipe.

[0011] Furthermore, a cold air valve is installed on the purge air branch pipe.

[0012] Furthermore, a temperature monitoring instrument is installed in the dust removal chamber, and a resistance thermometer is installed inside the ceramic sleeve heating air duct. The resistance thermometer is electrically connected to the temperature monitoring instrument.

[0013] Furthermore, the resistance thermometer includes a sheathed resistance thermometer.

[0014] This utility model provides an electrostatic precipitator steam heater, which adopts a layered layout of steam main pipe and steam branch pipe, so that the steam flow is evenly distributed and avoids local overheating or heat waste. The steam heater is used to heat the purge air, which can make full use of the latent heat of steam and has high heat exchange efficiency. Compared with electric heater, steam heater has a low failure rate, thus reducing maintenance costs and alleviating the technical problems of insufficient capacity, unstable electric field operation and high maintenance costs in the prior art. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 is a schematic diagram of an electrostatic precipitator steam heater provided in an embodiment of this utility model.

[0017] In the diagram: 1. Steam header, 2. Cold reheat steam source, 3. Steam branch pipe, 4. Steam heater, 5. Drain pipe, 6. Soot blower, 7. Purge air header, 8. Blower, 9. Purge air branch pipe, 10. Porcelain sleeve heated air duct, 11. First steam inlet shut-off valve, 12. Second steam inlet shut-off valve, 13. First drain shut-off valve, 14. Second drain shut-off valve, 15. Duct shut-off valve, 16. Drain manual valve, 17. Drain electric valve, 18. Temperature sensor, 19. Pressure sensor, 20. Check valve, 21. Cold air valve. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Figure 1 is a schematic diagram of an electrostatic precipitator steam heater according to an embodiment of the present invention. As shown in Figure 1, it includes: a steam main pipe 1, the air inlet of which is connected to a cold reheat steam source 2 of a thermal power plant, multiple steam branch pipes 3 connected to the steam main pipe 1, each steam branch pipe 3 being connected to a steam heater 4; and a drain pipe 5 of the steam heater 4 connected to a soot blower 6 in the selective catalytic reduction reaction zone of the thermal power plant.

[0020] Specifically, as shown in Figure 1, it also includes a purge air main pipe 7, one end of which is connected to a fan 8. Multiple purge air branch pipes 9 are connected to the purge air main pipe 7, and each purge air branch pipe 9 is connected to the air inlet of a steam heater 4. Multiple porcelain sleeve heating air pipes 10 are provided at the air outlet of the steam heater 4. The multiple porcelain sleeve heating air pipes 10 are connected to the dust removal chamber of the electrostatic precipitator for hot air purging of the insulating porcelain sleeves of each electric field in the dust removal chamber.

[0021] Specifically, as shown in Figure 1, a first steam inlet shut-off valve 11 and a second steam inlet shut-off valve 12 are sequentially installed on the steam branch pipe 3 to regulate the steam inlet flow rate of the steam branch pipe 3.

[0022] A first drain stop valve 13 and a second drain stop valve 14 are sequentially installed on the drain pipe 5 to adjust the drain discharge flow rate and thereby control the purging air temperature of the ceramic sleeve heating air pipe 10.

[0023] A duct shut-off valve 15 is installed on the ceramic sleeve heating duct 10 to regulate the purge air volume.

[0024] A manual drain valve 16 and an electric drain valve 17 are installed sequentially near the steam outlet on the steam header 1.

[0025] In some optional embodiments provided by this utility model, the steam main pipe 1 is made of seamless steel pipe 20G, Φ76*3; the steam branch pipe 3 is made of seamless steel pipe 20G, Φ45*2.5; and the drain pipe 5 is made of seamless steel pipe 20G, Φ28*4.

[0026] In some optional embodiments provided by this utility model, the first steam inlet shut-off valve 13 and the second steam inlet shut-off valve 14 include a DN40 shut-off valve, a drain manual valve 16 and a drain electric valve 17 with a nominal diameter of D65, a design temperature of 450℃ and a design pressure of 4MPa.

[0027] The first drain stop valve 13 and the second drain stop valve 14 include DN32 stop valves with a design temperature of 200℃ and a design pressure of 4MPa.

[0028] The duct stop valve 15 includes a DN50 stop valve.

[0029] As shown in Figure 1, a temperature sensor 18 and a pressure sensor 19 are also installed at the connection between the steam branch pipe 3 and the steam heater 4; wherein...

[0030] Temperature sensor 18 is used to monitor the inlet temperature of steam heater 4;

[0031] Pressure sensor 19 is used to monitor the inlet pressure of steam heater 4.

[0032] Optionally, the temperature sensor 18 includes a bimetallic thermometer.

[0033] Optionally, as shown in Figure 1, a temperature sensor 18 and a pressure sensor 19 are also provided at the connection between the drain pipe 5 and the steam heater 4, respectively, to monitor the temperature and pressure inside the drain pipe 5.

[0034] Specifically, as shown in Figure 1, a check valve 20 is installed on the purge air main pipe 7, and a cold air valve 21 is installed on the purge air branch pipe 9. The cold air valve 21 is used to regulate the air volume.

[0035] In one optional embodiment of this utility model, a temperature monitoring instrument is installed in the dust removal chamber, and a resistance thermometer is installed inside the ceramic-sheathed heating air duct 10. The resistance thermometer is electrically connected to the temperature monitoring instrument. Optionally, the resistance thermometer includes a sheathed resistance thermometer.

[0036] Specifically, the temperature monitoring instrument is used to monitor the temperature of the purge air in real time and issue an alarm signal when the temperature of the purge air is lower than a first preset threshold (e.g., 110°C) or higher than a second preset threshold (e.g., 140°C).

[0037] As can be seen from the above description, the present invention provides an electrostatic precipitator steam heater, which has the following technical effects compared with the prior art:

[0038] (1) This utility model adopts a modular steam pipeline design, with a layered layout of steam main pipe and steam branch pipe, and even distribution of steam flow to avoid local overheating or heat waste; the pipeline is made of seamless steel pipe 20G material, which is resistant to high temperature (350℃) and high pressure (4MPa), with pipeline pressure drop ≤0.2MPa and long service life.

[0039] (2) Using a steam heater to heat the purge air can make full use of the latent heat of steam and achieve high heat exchange efficiency (heat exchange efficiency increased by 30%).

[0040] (3) Compared with electric heaters, steam heaters have a lower failure rate, resulting in lower maintenance costs and alleviating the technical problems of insufficient capacity, unstable electric field operation and high maintenance costs in existing technologies.

[0041] (4) The connection relationship simplifies the operation and maintenance process. The temperature of the blow air is monitored in real time by the thermal resistance thermometer embedded in the porcelain sleeve. The alarm is automatically triggered when the limit is exceeded. The operation and maintenance personnel can quickly locate the fault point and the response time is shortened by 80%.

[0042] (5) Energy saving and consumption reduction: Using surplus cold resteam from thermal power plants for heat exchange can save electricity costs, reduce emissions and increase efficiency.

[0043] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0044] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An electrostatic precipitator steam heater, characterized in that, include: The system includes a steam header, whose inlet is connected to the cold reheat steam source of the power plant. Multiple steam branch pipes are connected to the steam header, each connected to a steam heater. The drain pipe of the steam heater is connected to the soot blower in the selective catalytic reduction reaction zone of the power plant. The system also includes a purge air header, one end of which is connected to a blower. Multiple purge air branch pipes are connected to the purge air header, each connected to an inlet of one of the steam heaters. Multiple porcelain-insulated heating air ducts are installed at the outlet of the steam heater, and these ducts are connected to the dust removal chamber of the electrostatic precipitator for hot air purging of the insulating porcelain insulators of each electric field within the dust removal chamber.

2. The electrostatic precipitator steam heater according to claim 1, characterized in that: The steam branch pipe is equipped with a first steam inlet shut-off valve and a second steam inlet shut-off valve in sequence; the drain pipe is equipped with a first drain shut-off valve and a second drain shut-off valve in sequence; and the ceramic sleeve heating air duct is equipped with an air duct shut-off valve.

3. The electrostatic precipitator steam heater according to claim 2, characterized in that: The first steam inlet shut-off valve and the second steam inlet shut-off valve are both DN40 shut-off valves; the first condensate shut-off valve and the second condensate shut-off valve are both DN32 shut-off valves; and the duct shut-off valve is a DN50 shut-off valve.

4. The electrostatic precipitator steam heater according to claim 1, characterized in that: A temperature sensor and a pressure sensor are also provided at the connection between the steam branch pipe and the steam heater; the temperature sensor is used to monitor the inlet temperature of the steam heater; the pressure sensor is used to monitor the inlet pressure of the steam heater.

5. The electrostatic precipitator steam heater according to claim 4, characterized in that: The temperature sensor includes a bimetallic thermometer.

6. The electrostatic precipitator steam heater according to claim 1, characterized in that: A manual drain valve and an electric drain valve are sequentially installed on the steam header near the steam outlet.

7. The electrostatic precipitator steam heater according to claim 1, characterized in that: A check valve is installed on the main purging air pipe.

8. The electrostatic precipitator steam heater according to claim 1, characterized in that: A cold air valve is installed on the purge air branch pipe.

9. The electrostatic precipitator steam heater according to claim 1, characterized in that: A temperature monitoring instrument is installed in the dust removal chamber, and a resistance thermometer is installed inside the ceramic sleeve heating air duct. The resistance thermometer is electrically connected to the temperature monitoring instrument.

10. The electrostatic precipitator steam heater according to claim 9, characterized in that: The resistance thermometer includes a sheathed resistance thermometer.

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