Drainage energy recovery system of photo-thermal power station

Abstract

The utility model discloses a drainage energy recovery system of a photo-thermal power station, which comprises a steam water supply circulating system and a heating circulating water system, the steam water supply circulating system and the heating circulating water system are connected through a drainage system, and the drainage system comprises a blowdown flash tank. A drainage outlet of the low-pressure heater, a drainage outlet of the high-pressure heater and a drainage outlet of the steam generation heat exchanger are connected with an inlet of the blowdown flash tank through branch pipelines, an outlet of the blowdown flash tank is communicated with a hot water outlet pipeline of the heating heat exchanger through a pipeline and then connected with a user, and a drainage pump is arranged on an outlet pipeline of the blowdown flash tank. Potential safety hazards caused by back pressure rise of the steam turbine can be avoided, heat released by drain water can be effectively recycled, and heat efficiency of a unit is improved.

Description

Technical Field

[0001] This utility model relates to a hydrophobic energy recovery system for a solar thermal power plant, belonging to the technical field of solar thermal power plants and energy storage power plants. Background Technology

[0002] Concentrated solar power (CSP) is currently positioned for peak shaving and energy storage, featuring flexible schemes and diverse development models, making it a major development direction for new energy power generation. CSP is characterized by frequent start-ups, shutdowns, and load changes, placing higher demands on the steam-water system. In conventional CSP plants, the emergency condensate drains from the high-pressure and low-pressure heaters are typically connected to the air-cooled exhaust system. However, when the condensate becomes saturated steam under back pressure, the increased specific volume of the exhaust steam ultimately leads to an increase in turbine back pressure, causing excessively high back pressure or reaching alarm back pressure levels, posing a threat to the safe operation of the turbine. Furthermore, the heat released by this condensate cannot be recovered, resulting in energy waste. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a solar thermal power plant condensate drain energy recovery system, which can not only solve the safety hazards caused by the rise of turbine back pressure, but also effectively recover the heat released by the condensate drain and improve the unit's thermal efficiency.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0005] A solar thermal power plant hydrophobic energy recovery system includes a steam feedwater circulation system and a heating circulating water system, which are connected by a hydrophobic system.

[0006] The steam feedwater circulation system includes a deaerator. The outlet of the deaerator is connected to the inlet of the high-pressure heater, the outlet of the high-pressure heater is connected to the inlet of the steam generator heat exchanger, the steam outlet of the steam generator heat exchanger is connected to the steam turbine, the exhaust steam outlet of the steam turbine is connected to the exhaust steam device, the outlet of the exhaust steam device is connected to the inlet of the low-pressure heater, and the outlet of the low-pressure heater is connected to the inlet of the deaerator.

[0007] The heating circulating water system includes a heating heat exchanger. The hot water outlet of the heating heat exchanger is connected to the user through a pipe. The user's heating return water is connected to the heating return water inlet of the heating heat exchanger through a pipe. A heating circulating water pump is installed on the heating return water inlet pipe of the heating heat exchanger.

[0008] The drainage system includes a drain expansion tank, and the drain outlets of the low-pressure heater, high-pressure heater, and steam generator heat exchanger are connected to the inlet of the drain expansion tank via branch pipes. The outlet of the drain expansion tank is connected to the hot water outlet pipe of the heating heat exchanger via a pipe and then connected to the user. A drain pump is installed on the outlet pipe of the drain expansion tank.

[0009] A further improvement of this utility model is that: a valve is provided at the outlet of the condensate pump, and a valve is provided at the hot water outlet of the heating heat exchanger.

[0010] A further improvement of this utility model is that a condensate pump is installed on the outlet pipe of the exhaust device and a feed water pump is installed on the outlet pipe of the deaerator.

[0011] A further improvement of this utility model is that valves are provided on the drain outlet pipes of the low-pressure heater, the high-pressure heater, and the steam generator heat exchanger.

[0012] The technological advancements achieved by this utility model due to the adoption of the above technical solution are as follows:

[0013] This invention not only solves the safety hazards caused by the rise of turbine back pressure in the prior art, but also effectively recovers the heat released by the condensate and improves the thermal efficiency of the unit.

[0014] The drainage system of this invention discharges emergency drainage from any high-pressure heater, low-pressure heater, or steam generator heat exchanger into a blowdown expansion tank. The emergency drainage expands to saturated drainage in the blowdown expansion tank, and then, via a drainage pump, is sent to the heating circulating water system for user heating. This effectively recovers the heat released by the drainage, improves the unit's thermal efficiency, and achieves dual recovery of energy from the heater drainage and the working fluid, ensuring full utilization of energy and improving the unit's economy. Attached Figure Description

[0015] Figure 1 This is a connection diagram of this utility model;

[0016] Among them, 1. Steam turbine, 2. Exhaust steam device, 3. Condensate pump, 4. Low-pressure heater, 5. Deaerator, 6. Feed water pump, 7. High-pressure heater, 8. Steam generating heat exchanger, 9. Blowout expansion tank, 10. Drain pump, 11. Heating heat exchanger, 12. Heating circulating water pump, 13. User. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to embodiments:

[0018] like Figure 1 As shown, a solar thermal power plant condensate energy recovery system includes a steam feedwater circulation system and a heating circulating water system. The steam feedwater circulation system and the heating circulating water system are connected by a condensate system. The condensate system discharges emergency condensate from any high-pressure heater 7 or low-pressure heater 4 and steam generator heat exchanger 8 into a blowdown expansion container 9. The emergency condensate is expanded into saturated condensate in the blowdown expansion container 9 and then sent to the heating circulating water system for users' heating needs via a condensate pump 10.

[0019] The steam feedwater circulation system includes a turbine unit 1, an exhaust system 2, a high-pressure heater 7, a low-pressure heater 4, a deaerator 5, a feedwater pump 6, a condensate pump 3, and a steam generator heat exchanger 8. The outlet of the deaerator 5 is connected to the inlet of the high-pressure heater 7, the outlet of the high-pressure heater 7 is connected to the inlet of the steam generator heat exchanger 8, the steam outlet of the steam generator heat exchanger 8 is connected to the turbine unit 1, the exhaust outlet of the turbine unit 1 is connected to the exhaust system 2, the outlet of the exhaust system 2 is connected to the inlet of the low-pressure heater 4, and the outlet of the low-pressure heater 4 is connected to the inlet of the deaerator 5. All components are connected by pipelines, and valves are installed on each section of the pipeline. A condensate pump 3 is installed on the outlet pipeline of the exhaust system 2, and a feedwater pump 6 is installed on the outlet pipeline of the deaerator 5.

[0020] The feedwater is preheated by the low-pressure heater 4 to increase its temperature before entering the deaerator 5 for deoxygenation. It is then pressurized by the feedwater pump 6 and sent to the steam generator heat exchanger 8. In the steam generator heat exchanger 8, the feedwater is heated and evaporated into steam. The resulting high-temperature, high-pressure steam is sent to the turbine 1 to expand and perform work. The exhaust steam, after performing work, enters the exhaust steam device 2 to be condensed into water, and then is sent back to the deaerator 5 for recirculation via the condensate pump 3.

[0021] The heating circulating water system includes a heating heat exchanger 11 and a heating circulating water pump 12. The hot water outlet of the heating heat exchanger 11 is connected to user 13 via a pipe. The heating return water from user 13 is connected to the heating return water inlet of the heating heat exchanger 11 via a pipe, and the heating circulating water pump 12 is installed on the heating return water inlet pipe of the heating heat exchanger 11. The heating return water from user 13 after heating is sent back to the heating heat exchanger 11 by the heating circulating water pump 12, and after being heated, it enters user 13 for heating.

[0022] The drainage system includes a blowdown expansion tank 9. The drain outlets of the low-pressure heater 4, high-pressure heater 7, and steam generator heat exchanger 8 are connected to the inlet of the blowdown expansion tank 9 via branch pipes. The outlet of the blowdown expansion tank 9 is connected to the hot water outlet pipe of the heating heat exchanger 11 via a pipe and then connected to the user 13. A drain pump 10 is installed on the outlet pipe of the blowdown expansion tank 9. A valve 1 is installed at the outlet of the drain pump 10, and a valve 2 is installed at the hot water outlet of the heating heat exchanger 11.

[0023] When the water level inside any high-pressure heater or low-pressure heater rises abnormally for some reason, such as pipe rupture or leakage, it is necessary to discharge the emergency condensate; or when the emergency condensate of the steam generator heat exchanger 8 needs to be discharged, open the valve on the corresponding branch pipeline to discharge the emergency condensate to the drain expansion container 9, where the drain expansion container 9 is expanded to saturate condensate.

[0024] When the sewage expansion container 9 discharges condensate, valve 2 is closed and valve 1 is opened, and the saturated condensate is sent to user 13 for heating by the condensate pump 10.

[0025] When the sewage expansion container 9 does not need to discharge condensate, valve one is closed and valve two is opened. The heating return water after the user 13 is heated is sent to the heating heat exchanger 11 by the heating circulating water pump 12, and after being heated, it enters the user 13 for heating.

Claims

1. A hydrophobic energy recovery system for a solar thermal power plant, characterized in that: It includes a steam feedwater circulation system and a heating water circulation system, which are connected by a drainage system. The steam feedwater circulation system includes a deaerator (5), the outlet of the deaerator (5) is connected to the inlet of the high-pressure heater (7), the outlet of the high-pressure heater (7) is connected to the inlet of the steam generator heat exchanger (8), the steam outlet of the steam generator heat exchanger (8) is connected to the steam turbine (1), the exhaust steam outlet of the steam turbine (1) is connected to the exhaust steam device (2), the outlet of the exhaust steam device (2) is connected to the inlet of the low-pressure heater (4), and the outlet of the low-pressure heater (4) is connected to the inlet of the deaerator (5). The heating circulating water system includes a heating heat exchanger (11), the hot water outlet of the heating heat exchanger (11) is connected to the user (13) through a pipe, the heating return water of the user (13) is connected to the heating return water inlet of the heating heat exchanger (11) through a pipe, and a heating circulating water pump (12) is installed on the heating return water inlet pipe of the heating heat exchanger (11). The drainage system includes a sewage expansion container (9), and the drainage outlets of the low-pressure heater (4), high-pressure heater (7) and steam generator heat exchanger (8) are connected to the inlet of the sewage expansion container (9) through branch pipes. The outlet of the sewage expansion container (9) is connected to the hot water outlet pipe of the heating heat exchanger (11) through a pipe and then connected to the user (13). A drainage pump (10) is installed on the outlet pipe of the sewage expansion container (9).

2. The solar thermal power plant hydrophobic energy recovery system according to claim 1, characterized in that: The outlet of the condensate pump (10) is equipped with valve one, and the hot water outlet of the heating heat exchanger (11) is equipped with valve two.

3. The solar thermal power plant hydrophobic energy recovery system according to claim 1, characterized in that: A condensate pump (3) is installed on the outlet pipe of the exhaust device (2), and a water supply pump (6) is installed on the outlet pipe of the deaerator (5).

4. The solar thermal power plant hydrophobic energy recovery system according to claim 1, characterized in that: Valves are installed on the drain outlet pipes of the low-pressure heater (4), the high-pressure heater (7), and the steam generator heat exchanger (8).

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