Energy stepped utilization heat supply system of heat supply nuclear power station steam turbine

Abstract

The invention discloses an energy stepped utilization heat supply system of a heat supply nuclear power station steam turbine, and belongs to the technical field of high-power nuclear power station steam turbine heat supply. In order to solve the problem that the plant power consumption rate of heat supply of a steam turbine of a high-power nuclear power station is high, the method comprises the steps that secondary loop main steam of the heat supply nuclear power station enters a high-pressure cylinder through a steam-water separation reheater; exhaust steam of the high-pressure cylinder enters the low-pressure cylinder through the steam-water separation reheater; heating extracted steam is conveyed to a heat supply network heater of an initial heat supply network in the nuclear power station; heat supply network circulating water is conveyed to a heat supply network water supply pipeline through the in-plant heat supply network initial station front heat supply network heater and the nuclear power station internal heat supply network initial station heat supply network heater; heat supply steam enters the heat supply network circulating water pump driving steam turbine through a steam interface for the heat supply network circulating water pump driving steam turbine to drive the steam-driven heat supply network circulating water pump to operate, and exhaust steam of the heat supply network circulating water pump driving steam turbine is conveyed to a front heat supply network heater of an in-plant heat supply network initial station to heat return water of a heat supply network. The invention is used for the heat supply nuclear power station.

Description

Technical Field

[0001] The invention relates to an energy ladder utilization heating system for a steam turbine of a heating nuclear power plant, belonging to the technical field of heating of steam turbines in high-power nuclear power plants. Background Art

[0002] With the continuous development of urbanization, the scale of heating is constantly expanding. At the same time, in order to make efficient use of energy, the heating method is becoming more centralized. At present, large-scale coal-fired cogeneration units are mainly responsible for heating. The main fuel is still fossil fuels. It is difficult to avoid the emission of chemical pollutants such as carbon and sulfur. The livelihood demand for centralized heating has become a major obstacle. Compared with other forms of heating such as traditional fossil energy, nuclear power plant heating has very obvious environmental advantages: nuclear fission has a high energy density. Compared with coal-fired boilers of the same power, the annual transportation volume of nuclear fuel is only about one hundred thousandth of the amount of coal; nuclear energy heating can also significantly reduce carbon dioxide emissions.

[0003] However, existing large-power nuclear power plant steam turbine heating mostly uses high-pressure cylinder exhaust steam extraction modification to achieve heating, but fails to better plan the heating source in combination with the energy level, further reduce carbon emissions and use energy in a tiered and rational manner.

[0004] In addition, when the steam turbines of large-power nuclear power plants are operating for heating, the circulating pumps in the heating network's first station require a large amount of plant electricity. If the plant electricity consumption rate is reduced, it is also an urgent problem to be solved for the heating of steam turbines in large-power nuclear power plants. Summary of the invention

[0005] The purpose of the present invention is to solve the problem of high power consumption rate of steam turbine heating in large-power nuclear power plants, and to provide a step-by-step energy utilization heating system for heating nuclear power plant steam turbines.

[0006] The energy ladder utilization heating system for heating nuclear power plant steam turbines of the present invention comprises:

[0007] The secondary circuit main steam of the heating nuclear power plant enters the high-pressure cylinder through the steam-water separation reheater to perform work;

[0008] The exhaust steam from the high-pressure cylinder passes through the steam-water separation reheater and then enters the low-pressure cylinder to perform work;

[0009] A heating steam extraction interface is led out between the high-pressure cylinder and the steam-water separation reheater, and the heating steam extraction is transported to the heating network heater at the first station of the heating network in the nuclear power plant through the heating steam extraction interface;

[0010] The circulating water in the heat network return pipe is pressurized by the heat network circulating water pump, and then transported to the pre-heat network heater at the first station of the heat network in the plant, and heated by the exhaust steam of the steam turbine driven by the heat network circulating water pump, and then transported to the heat network heater at the first station of the heat network in the nuclear power plant, heated by the heating steam, and then transported to the heat network water supply pipe for heating;

[0011] The heating network circulating water pump includes a steam-driven heating network circulating water pump and an electric heating network circulating water pump;

[0012] When a steam-driven heat network circulating water pump is used, a steam interface for driving the steam turbine of the heat network circulating water pump is arranged between the heating steam extraction interface and the heat network heater at the first station in the heat network of the nuclear power plant. The heating steam enters the heat network circulating water pump to drive the steam turbine through the steam interface for driving the steam turbine of the heat network circulating water pump, and drives the steam-driven heat network circulating water pump to operate. The exhaust steam of the steam turbine driven by the heat network circulating water pump is transported to the pre-heating network heater at the first station of the heat network in the plant to heat the return water of the heat network.

[0013] Preferably, the heating steam extraction is further provided with: a safety valve, a pneumatic check valve, a hydraulic fast pipe valve, a shut-off valve and a flow meter on the pipeline between the heating steam extraction interface and the heating network heater of the first station in the nuclear power plant.

[0014] Preferably, a heating network water supply flow meter is provided on the water outlet pipe on the water side of the heating network heater at the first station of the heating network in the nuclear power plant.

[0015] Preferably, an electric gate valve for the steam inlet pipeline of the heating network circulating water pump driven steam turbine, a flow meter for the steam inlet pipeline of the heating network circulating water pump driven steam turbine and a hydraulic regulating valve for the steam inlet pipeline of the heating network circulating water pump driven steam turbine are arranged between the steam interface for the heating network circulating water pump driven steam turbine and the heating network circulating water pump driven steam turbine.

[0016] Preferably, an electric butterfly valve for exhaust steam pipe of the heat network circulating water pump-driven steam turbine is arranged between the heat network circulating water pump-driven steam turbine and the pre-heat network heater of the first station of the heat network in the plant.

[0017] Preferably, the low-pressure cylinder includes a first low-pressure cylinder, a second low-pressure cylinder and a third low-pressure cylinder.

[0018] Preferably, a first low-pressure cylinder steam inlet fully sealed hydraulic quick-opening valve is provided between the first low-pressure cylinder and the steam-water separation reheater;

[0019] A second low-pressure cylinder steam inlet fully sealed hydraulic quick-opening valve is provided between the second low-pressure cylinder and the steam-water separation reheater;

[0020] A third low-pressure cylinder steam inlet fully sealed hydraulic quick-opening valve is arranged between the third low-pressure cylinder and the steam-water separation reheater.

[0021] Preferably, the water side water inlet pipe of the pre-heating network heater is between the heat network circulating water pump and the pre-heating network heater of the first station of the heat network in the factory;

[0022] The water outlet pipe of the preheating network heater at the first station of the heating network in the plant and the heating network heater at the first station of the heating network in the nuclear power plant is also used as the water inlet pipe of the heating network heater.

[0023] The water outlet pipe of the heating network heater at the first station of the heating network in the nuclear power plant is located between the heating network heater at the first station of the heating network in the nuclear power plant and the heating network water supply pipe.

[0024] Preferably, the preheating network heaters at the first station of the in-plant heating network are connected in parallel in multiple units;

[0025] The heating network heaters at the first station of the heating network in the nuclear power plant are connected in parallel.

[0026] The steam-driven heating network circulating water pump and the electric heating network circulating water pump are used in parallel in multiple units.

[0027] Preferably, the heat network circulating water in the heat network return pipe is subjected to a decontamination treatment using a decontamination device before being pressurized by a heat network circulating water pump.

[0028] Advantages of the present invention: The energy cascade utilization heating system for the steam turbine of a heating nuclear power plant described in the present invention, based on the use of high-pressure cylinder exhaust steam for heating in the steam turbine of a large-power nuclear power plant, uses a steam-driven heat network circulating water pump and is driven by a heating steam source to drive the exhaust steam of the steam turbine to be used as preliminary heating of the heat network circulating water, thereby reducing the plant electricity consumption rate and improving the economy of energy cascade utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the energy ladder utilization heating system of the steam turbine of the heating nuclear power plant described in the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0032] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0033] Embodiment 1:

[0034] Combine the following Figure 1 This embodiment is described. This embodiment is a step-by-step energy utilization heating system for heating a nuclear power plant steam turbine. The nuclear power plant steam turbine includes:

[0035] The secondary circuit main steam of the heating nuclear power plant enters the high-pressure cylinder 1 through the steam-water separation reheater 9 to perform work;

[0036] The exhaust steam from the high-pressure cylinder 1 passes through the steam-water separation reheater 9 and then enters the low-pressure cylinder to perform work;

[0037] A heating steam extraction interface 8 is led out between the high-pressure cylinder 1 and the steam-water separation reheater 9, and the heating steam extraction is transported to the heating network heater 18 of the first station of the heating network in the nuclear power plant through the heating steam extraction interface 8;

[0038] The heat network circulating water in the heat network return water pipeline is pressurized by the heat network circulating water pump, and then transported to the pre-heat network heater 15 at the first station of the heat network in the plant, and is heated by the exhaust steam of the steam turbine 22 driven by the heat network circulating water pump, and then transported to the heat network heater 18 at the first station of the heat network in the nuclear power plant, and is heated by the heating steam, and then transported to the heat network water supply pipeline for heating;

[0039] The heat network circulating water pump comprises a steam-driven heat network circulating water pump 20 and an electric heat network circulating water pump 21;

[0040] When a steam-driven heat network circulating water pump 20 is used, a heat network circulating water pump driving steam turbine steam interface 29 is provided between the heating steam extraction interface 8 and the heat network first station heat network heater 18 in the nuclear power plant. The heating steam enters the heat network circulating water pump driving steam turbine 22 through the heat network circulating water pump driving steam turbine steam interface 29 to drive the steam-driven heat network circulating water pump 20 to operate. The exhaust steam of the heat network circulating water pump driving steam turbine 22 is transported to the pre-heat network heater 15 at the first station of the heat network in the plant to heat the heat network return water.

[0041] Furthermore, the pipeline between the heating steam extraction interface 8 and the heating network heater 18 of the first station of the heating network in the nuclear power plant is also provided with: a safety valve 10, a pneumatic check valve 11, a hydraulic fast pipe valve 12, a shut-off valve 13 and a flow meter 14.

[0042] Furthermore, a heat network water supply flow meter 28 is provided on the water outlet pipe 19 of the heat network heater at the first station of the heat network in the nuclear power plant.

[0043] Furthermore, an electric gate valve 23 for the steam inlet pipeline of the heating network circulating water pump driven steam turbine, a flow meter 24 for the steam inlet pipeline of the heating network circulating water pump driven steam turbine and a hydraulic regulating valve 25 for the steam inlet pipeline of the heating network circulating water pump driven steam turbine are arranged between the steam interface 29 for the heating network circulating water pump driven steam turbine and the heating network circulating water pump driven steam turbine 22.

[0044] Furthermore, an electric butterfly valve 26 for exhaust steam pipe of the heat network circulating water pump driven steam turbine is arranged between the heat network circulating water pump driven steam turbine 22 and the pre-heat network heater 15 of the first station of the heat network in the factory.

[0045] Furthermore, the low-pressure cylinder includes a first low-pressure cylinder 2 , a second low-pressure cylinder 3 and a third low-pressure cylinder 4 .

[0046] Furthermore, a first low-pressure cylinder steam inlet fully sealed hydraulic quick-opening valve 5 is provided between the first low-pressure cylinder 2 and the steam-water separation reheater 9;

[0047] A second low-pressure cylinder steam inlet fully sealed hydraulically actuated quick-opening valve 6 is provided between the second low-pressure cylinder 3 and the steam-water separation reheater 9;

[0048] A third low-pressure cylinder steam inlet fully sealed hydraulic quick-opening valve 7 is provided between the third low-pressure cylinder 4 and the steam-water separation reheater 9.

[0049] Furthermore, between the heat network circulating water pump and the pre-heat network heater 15 at the first station of the heat network in the factory is a pre-heat network heater water side water inlet pipe 16;

[0050] Between the pre-heating network heater 15 at the first station of the plant heat network and the heat network heater 18 at the first station of the nuclear power plant heat network is the pre-heating network heater water side outlet pipe 17, which also serves as the heat network heater water inlet pipe;

[0051] The water outlet pipe 19 of the water side of the heating network heater at the first station of the heating network in the nuclear power plant is located between the heating network heater 18 at the first station of the heating network in the nuclear power plant and the heating network water supply pipe.

[0052] Furthermore, the pre-heating network heater 15 at the first station of the factory heating network is used in parallel in multiple units.

[0053] Furthermore, a plurality of heating network heaters 18 at the first station of the heating network in the nuclear power plant are used in parallel.

[0054] Furthermore, the steam-driven heating network circulating water pump 20 and the electric heating network circulating water pump 21 are used in parallel in multiple units.

[0055] Furthermore, the heat network circulating water in the heat network return pipe is subjected to a decontamination treatment by a decontamination device 27 before being pressurized by the heat network circulating water pump.

[0056] In the present invention, a high-power nuclear power steam turbine is provided with a high-pressure cylinder 1 and a plurality of low-pressure cylinders.

[0057] The main steam of the secondary circuit of the nuclear power plant passes through the steam-water separation reheater 9, is cooled by the high-pressure cylinder exhaust steam, and then enters the high-pressure cylinder 1 to perform work.

[0058] The exhaust steam from the high-pressure cylinder is heated by the secondary circuit main steam of the nuclear power plant through the steam-water separation reheater 9, and then enters the low-pressure cylinder through the steam inlet quick opening valve to perform work.

[0059] The methods for realizing large-scale centralized heating of large-power nuclear power steam turbines are as follows: heating extraction steam is taken from the high-pressure cylinder exhaust steam (between the high-pressure cylinder 1 and the steam-water separation reheater 9), and is connected to the heating network heater 18 at the first station of the heating network in the nuclear power plant through the heating extraction steam interface 8. A safety valve 10, a pneumatic check valve 11, a hydraulic fast pipe valve 12, an electric shut-off valve 13 and a flow meter 14 are provided on the heating steam pipeline in turn.

[0060] The circulating water in the heat network return pipe is pressurized by the decontaminator 27, the steam-driven heat network circulating water pump 20 and the electric heat network circulating water pump 21, and then passes through the water side inlet pipe 16 of the pre-heat network heater and enters the pre-heat network heater 15 at the first station of the heat network in the plant;

[0061] After being preliminarily heated by the exhaust steam of the steam turbine driven by the circulating water pump of the heat extraction network, it passes through the water side outlet pipe 17 of the pre-heating network heater (i.e. the water inlet pipe of the heat network heater) and enters the heat network heater 18 of the first station of the heat network in the nuclear power plant;

[0062] After being heated by the heating steam, it enters the water outlet pipe 19 (i.e., heating network water supply) of the heating network heater at the first station of the heating network in the nuclear power plant, and enters the heating network water supply pipe through the heating network water supply flowmeter 28 for heating.

[0063] In order to reduce the power consumption of the factory and improve the economic efficiency of energy ladder utilization, when using the steam-driven heat network circulating water pump, select the steam interface 29 for driving the steam turbine on the steam supply pipeline at the appropriate position of the heat supply pipeline;

[0064] The water enters the steam turbine and drives the circulating water pump of the heating network to operate through the electric gate valve 23 of the steam turbine steam inlet pipeline driven by the circulating water pump of the heating network, the flow meter 24 of the steam turbine steam inlet pipeline driven by the circulating water pump of the heating network, and the hydraulic regulating valve 25 of the steam turbine steam inlet pipeline driven by the circulating water pump of the heating network;

[0065] The exhaust steam of the steam turbine 22 driven by the circulating water pump of the heating network enters the pre-heating network heater 15 of the first station of the heating network in the factory through the electric butterfly valve 26 of the exhaust steam pipeline of the steam turbine driven by the circulating water pump of the heating network, and preliminarily heats the return water of the network, thereby realizing the cascade utilization of the energy of the heating steam and reducing the power consumption rate of the factory.

[0066] In the present invention, the number of low-pressure cylinders of the nuclear power steam turbine may be more than one, and may be three at most.

[0067] There are a maximum of 3 hydraulic quick-opening valves for the steam inlet to the low-pressure cylinder.

[0068] The preheating network heaters 15 at the first station of the factory heating network are generally used in parallel.

[0069] Generally, multiple heating network heaters 18 at the first station of the heating network in a nuclear power plant are used in parallel.

[0070] A plurality of steam-driven heat network circulating water pumps 20 and electric heat network circulating water pumps 21 are generally used in parallel.

[0071] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. An energy ladder utilization heating system for heating nuclear power plant steam turbines, characterized in that: include: The secondary circuit main steam of the heating nuclear power plant enters the high-pressure cylinder (1) through the steam-water separation reheater (9) to perform work; The exhaust steam from the high-pressure cylinder (1) passes through the steam-water separation reheater (9) and then enters the low-pressure cylinder to perform work; A heating steam extraction interface (8) is led out between the high-pressure cylinder (1) and the steam-water separation reheater (9), and the heating steam extraction is transported to a heating network heater (18) at the first station of the heating network in the nuclear power plant through the heating steam extraction interface (8); The heat network circulating water in the heat network return water pipeline is pressurized by the heat network circulating water pump, and then transported to the pre-heat network heater (15) at the first station of the heat network in the plant, and is heated by the exhaust steam of the steam turbine (22) driven by the heat network circulating water pump, and then transported to the heat network heater (18) at the first station of the heat network in the nuclear power plant, and is heated by the heating steam, and then transported to the heat network water supply pipeline for heating; The heating network circulating water pump comprises a steam-driven heating network circulating water pump (20) and an electric-driven heating network circulating water pump (21); When a steam-driven heat network circulating water pump (20) is used, a heat network circulating water pump driving steam turbine steam interface (29) is provided between the heating extraction steam interface (8) and the heat network heater (18) at the first station of the heat network in the nuclear power plant. The heating steam enters the heat network circulating water pump driving steam turbine (22) through the heat network circulating water pump driving steam turbine steam interface (29) to drive the steam-driven heat network circulating water pump (20) to operate. The exhaust steam of the heat network circulating water pump driving steam turbine (22) is transported to the pre-heat network heater (15) at the first station of the heat network in the plant to heat the heat network return water.

2. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: The pipeline between the heating extraction steam through the heating extraction steam interface (8) and the heating network heater (18) at the first station of the heating network in the nuclear power plant is also provided with: a safety valve (10), a pneumatic check valve (11), a hydraulic fast pipe valve (12), a shut-off valve (13) and a flow meter (14).

3. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: A heat network water supply flow meter (28) is provided on the water outlet pipe (19) on the water side of the heat network heater at the first station of the heat network in the nuclear power plant.

4. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: An electric gate valve (23) for a steam inlet pipeline of a heating network circulating water pump driven steam turbine, a flow meter (24) for a steam inlet pipeline of a heating network circulating water pump driven steam turbine, and a hydraulic regulating valve (25) for a steam inlet pipeline of a heating network circulating water pump driven steam turbine are arranged between the steam interface (29) for the heating network circulating water pump driven steam turbine and the heating network circulating water pump driven steam turbine (22).

5. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: An electric butterfly valve (26) for exhaust steam pipe of a heat network circulating water pump driven steam turbine is arranged between the heat network circulating water pump driven steam turbine (22) and the pre-heat network heater (15) of the first station of the heat network in the factory.

6. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: The low-pressure cylinder comprises a first low-pressure cylinder (2), a second low-pressure cylinder (3) and a third low-pressure cylinder (4).

7. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 6 is characterized in that: A first low-pressure cylinder steam inlet fully sealed hydraulically actuated quick-opening valve (5) is provided between the first low-pressure cylinder (2) and the steam-water separation reheater (9); A second low-pressure cylinder steam inlet fully sealed hydraulically actuated quick-opening valve (6) is provided between the second low-pressure cylinder (3) and the steam-water separation reheater (9); A third low-pressure cylinder steam inlet fully sealed hydraulically actuated quick-opening valve (7) is provided between the third low-pressure cylinder (4) and the steam-water separation reheater (9).

8. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: Between the heating network circulating water pump and the pre-heating network heater (15) at the first station of the heating network in the factory is a water inlet pipe (16) on the water side of the pre-heating network heater; Between the pre-heating network heater (15) at the first station of the heating network in the plant and the heating network heater (18) at the first station of the heating network in the nuclear power plant is a water outlet pipe (17) on the water side of the pre-heating network heater, which also serves as a water inlet pipe for the heating network heater; Between the heating network heater (18) at the first station of the heating network in the nuclear power plant and the heating network water supply pipeline is a water side outlet pipeline (19) of the heating network heater at the first station of the heating network in the nuclear power plant.

9. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: The preheating network heater (15) at the first station of the in-plant heating network is connected in parallel with multiple heaters; The heating network heater (18) at the first station of the heating network in the nuclear power plant is connected in parallel with multiple heaters; A plurality of the steam-driven heating network circulating water pumps (20) and the electric-driven heating network circulating water pumps (21) are used in parallel.

10. The energy ladder utilization heating system for heating nuclear power plant steam turbines according to claim 1 is characterized in that: The heat network circulating water in the heat network return water pipe is subjected to a decontamination treatment by a decontamination device (27) before being pressurized by the heat network circulating water pump.

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