JPH0366591B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a turbine plant, and in particular, to a turbine plant at the time of startup of a condenser circulating water system provided in a condenser, and furthermore, during normal operation. The present invention relates to an air purge operation method and an air purge device used to reliably perform an air purge operation.

(Prior Art) A steam turbine plant is known as a large-sized steam-powered machine that generates power by driving a steam turbine with steam guided from a high-temperature heat source (boiler or nuclear reactor). The basic cycle of this plant is based on the Rankine cycle, and is equipped with a condenser as a low-temperature heat source that maintains a sufficient temperature difference between it and the high-temperature heat source. The cooling medium of this condenser defines the low temperature side heat source temperature, and generally seawater, river water, lake water, etc. are used. Usually, a circulating water system is provided in the condenser in order to lead this water from the intake part of the water source to the condenser and then return it to the water discharge part from there.

Hereinafter, this condenser circulating water system will be explained with reference to the drawings based on an application example to a condenser of an atomic turbine plant.

In FIG. 1, reference numeral 1 indicates a condenser, and first and second water pipes 4 are used to flow circulating water between the condenser 1 and the water intake tank 2 and water discharge tank 3.
a and 4b are provided. In the route of the first and second water pipes 4a and 4b, there is a standpipe 5 for workers to enter and exit during periodic inspections.
a and 5b are provided respectively. Furthermore, vent pipes 6a and 6 are provided at the tops of the standpipe 5a and 5b, respectively.
b are connected, and the open ends thereof face the sump pits 7a and 7b, respectively. In addition, the symbols 8a and 8b in the figure indicate gate valves.

In the above configuration, water in the water intake tank 2 is extracted by a pump, sent as circulating water to the condenser 1 through the first water pipe 4a, and flows through a cooling pipe provided inside. Thereafter, the circulating water whose temperature has increased by absorbing heat from the steam is discharged from the condenser 1 to the water discharge tank 3 through the second water pipe 4b, where it is mixed with low temperature water and cooled. The behavior of the circulating water during operation of the condenser 1 is as described above, but before starting the condenser 1, the condenser 1, the first and second water pipes 4a, 4b, and the standpipes 5a, 5b Since air is flowing into the system, a so-called air purge operation is required to remove it from the system.

In this case, when the circulating water pressurized by the pump is guided to the first water pipe 4a, the air in the system is combined with the circulating water and most of it is sent to the water tank 3, but some air is left in the system. It remains in areas that are outside the mainstream of circulating water. Particularly, this stagnant air is significantly generated at the tops of the branched vertical pipes 5a and 5b. Vent pipe 6 for discharging this accumulated air
a, 6b are provided, and when the gate valves 8a, 8b are opened, the accumulated air is discharged from the tops of the standpipes 5a, 5b through the vent pipes 6a, 6b to the sump pits 7a, 7b.

(Problem to be Solved by the Invention) As mentioned above, when starting the condenser 1, the standpipe 5
The air remaining in a and 5b is discharged outside the system by opening the gate valves 8a and 8b, but when the circulating water is introduced into the system, the gate valves 8a and 8
If b is open, a large amount of circulating water flows into the sump pits 7a and 7b after the air is removed,
This will overflow the sump pits 7a and 7b. Therefore, when starting, the gate valve 8
A and 8b are fully closed, and then the standpipes 5a and 5b are also opened when they are filled with circulating water, but due to the compressibility of air, rapid opening of gate valves 8a and 8b is dangerous. There are cases. That is, when the gate valves 8a, 8b are opened when the pressure of the air trapped in the standpipes 5a, 5b increases, only the compressible air quickly escapes out of the system, followed by the water column. Standpipe 5a,
The closing member at the top of 5b collides. A so-called water hammer phenomenon may occur. Therefore, the gate valves 8a and 8b are operated to open little by little over time, but the starting operation tends to be very complicated.

On the other hand, during normal operation of the condenser 1, part of the air contained in the circulating water is separated from the circulating water and the standpipe 5
It gathers at the top of a and 5b. This air increases over time, so when a certain amount of air has gathered, the gate valves 8a and 8b are opened and the air is discharged outside the system, but monitoring the accumulated air requires the operator's help. There is a drawback that it is necessary.

The purpose of the present invention is to remove the air that accumulates at the top of the standpipe of the condenser circulating water system when starting the condenser, and the air that collects at the top of the same standpipe during normal operation without any manual intervention. It is an object of the present invention to provide an air purge operation method and an air purge device for a condenser circulating water system that automatically discharges air outside the system.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a first water pipe that connects a water intake tank and a condenser, a second water pipe that connects a condenser and a water discharge tank, and a first water pipe that connects a water intake tank and a condenser. at least one standpipe branched from each of the first and second water pipes, the circulating water is pressurized by a pump provided in the first water pipe, and is sent from the water intake tank to the condenser; In a method for venting air from a condenser circulating water system in which the water is then discharged to a water tank through a second water pipe, the tops of the standpipes of the first and second water pipes and each water chamber of the condenser are and communicate with each other via a connecting pipe, and when starting the condenser,
The air stagnant in each water chamber, the first and second water pipes, and each standpipe is sent to the water tank by filling the system with circulating water, and after the stagnant air is discharged, it is mixed with the circulating water and released into the system. It is characterized by sending circulating water from the flowing air into each standpipe and each communication pipe and discharging it into a water tank.

In addition, another invention provides a first connection between a water intake tank and a condenser.
A water pipe, a second water pipe that connects the condenser and the water tank, and at least one standpipe branched from each of the first and second water pipes, and the circulating water is connected to the first water pipe. The pressure is increased by a pump installed in the water pipe, and the water is sent from the water intake tank to the condenser.
In the condenser circulating water system, which is then discharged to the water tank through the second water pipe, the first
The top of the standpipe of the second water pipe and each water chamber of the condenser are communicated through communication pipes.

(Function) In the present invention, the top portions of the standpipes of the first and second water pipes are configured to communicate with the water chamber of the condenser via a communication pipe. Generally, the first and second water pipes are connected to the bottom of the water chamber of the condenser, so that the water chamber side occupies a higher position between the top of the standpipe and the water chamber.

When the pump provided in the first water pipe is started to start the condenser, the circulating water flows into the first water pipe,
The inlet side water chamber, condenser cooling pipe, outlet side water chamber, and second water pipe are sequentially filled, and in this process, the air filling the system is also sequentially sent to the water discharge tank. In other words, the top of the standpipe of the first water pipe and the inlet side water chamber are communicated via the connecting pipe, and the air pushed up to the top of the standpipe by the circulating water passes through the connecting pipe to the inlet side water chamber at a higher level. He is forced to escape into the room.

In addition, at the top of the standpipe of the second water pipe, a flow of circulating water is formed from the time when the circulating water flows into the outlet side water chamber to the standpipe at a lower position via the communication pipe, Air is transported to the second place by circulating water.
It escapes into the water pipe.

On the other hand, even after the accumulated air in the system is discharged to the water tank, the air contained therein continues to flow into the system together with the circulating water. At this time, the flow that passes through the communication pipe in the standpipe of the first water pipe and the flow that passes through the communication pipe in the standpipe of the second water pipe, so even if air is mixed in, each It does not remain at the top of the pipe, but is carried downstream with the circulating water and finally discharged into the water tank. In other words, in the condenser circulating water system according to the present invention, the flow of circulating water is maintained in all areas including the standpipe, and after the accumulated air is discharged, air mixed in the circulating water is continuously discharged to the outside of the system. be done.

(Example) An example of the present invention will be described with reference to FIG.
In the configuration shown in FIG. 2, the same components as those shown in FIG. 1 are given the same reference numerals, and their explanations will be omitted.

In FIG. 2, the standpipe 5a of the first water pipe 4a
The standpipe 5b of the second water pipe 4b is provided with communication pipes 10a and 10b that communicate with the inlet water chamber 9a and the outlet water chamber 9b, respectively. Here, one end of each communication pipe 10a, 10b is connected to the standpipe 5a, 5b.
The other end is connected to the inlet and outlet water chambers 9a and 9b located at a higher position than the top.

In addition, the code|symbol 11 in the figure has shown the pump with which the 1st water pipe 4a is equipped.

The air venting operation of this embodiment proceeds as follows. Atmospheric pressure acts inside the first water pipe 4a before the condenser 1 is started, and the inlet water chamber 9a, the cooling pipe of the condenser 1, the outlet water chamber 9b, and the second Most of the system including the inside of the water pipe 4b is filled with air. Here, when the pump 11 is started, the circulating water flows into the first water pipe 4a, and the internal air is released downstream. Then, circulating water flows throughout the entire area below the inlet side water chamber 9a, and air in the system is discharged to the water discharge tank 3. When the circulating water fills almost the entire area of the first and second water pipes, etc., the water level in the standpipe 5a begins to rise, and the air inside collects at the top, but this air passes through the connecting pipe 10a and flows into the inlet side water. It is discharged into chamber 9a. Further, the air remaining in the standpipe 4b is discharged to the second water pipe 4b by circulating water flowing from the outlet side water chamber 9b through the communication pipe 10b.

In this way, all the accumulated air is discharged outside the system when starting the condenser, but there is no need to operate the gate valves 8a, 8b, etc. as in the conventional case, and the burden on the operator is greatly reduced. In addition, the standpipe 5a, 5b
The safety of the equipment is maintained because the water hammer phenomenon of circulating water does not occur while the air inside is being released.

On the other hand, even after the condenser 1 is started after the above-mentioned water filling, air is mixed with the circulating water and carried into the system. If this air is separated from the circulating water in the circulating water stagnation area, it will remain there, but after filling with water, each standpipe 5a, 5b is connected to the connecting pipe 10.
Since a flow is formed via a and 10b, all entrained air is continuously carried downstream. That is, the air flowing into the standpipe 5a is carried to the inlet water chamber 9a via the communication pipe 10a, and the air guided to the standpipe 5b is carried to the second water pipe 4b by the flow from the communication pipe 10b. air is pumped out, and no air stagnation occurs within the system.

In this way, this air purge operation during normal operation can be performed automatically without the operator's intervention.
The burden on the operator is greatly reduced.

Furthermore, this embodiment is excellently useful when applied to an atomic turbine plant. That is, in general, in a nuclear power turbine plant, the circulating water system in the area connected to the condenser 1 is located within the turbine building, and air circulating water etc. discharged into the sump pits 7a and 7b are transported to the radiation controlled area. This circulating water containing radioactive waste cannot be disposed of unless it passes through a waste treatment device, but in the circulating water system of this example, the circulating water is transported outside the radiation control area and is not used for waste treatment. It becomes possible to dispose of the product without undergoing processing using the device.

〔Effect of the invention〕

As is clear from the above description, the present invention provides communication between the tops of the standpipe of the first and second water pipes provided in the condenser circulating water system and each water chamber of the condenser through a connecting pipe. When starting the condenser,
The air stagnant in each water chamber, the first and second water pipes, and each standpipe is sent to the water tank by filling the system with circulating water, and after the stagnant air is discharged, it is mixed with the circulating water and released into the system. Since the flowing air is sent through each standpipe and each communication pipe to circulate water and discharged to the water discharge tank, the air that collects at the top of the standpipe when the condenser is started and during operation is removed. can be discharged from the system without bothering the operator, resulting in the effect of reducing the burden on the operator.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an example of a condenser circulating water system in a conventional nuclear turbine plant, and FIG. 2 is a system diagram showing a device used in the air purge operation method according to the present invention. 1... Condenser, 2... Water intake tank, 3... Water discharge tank,
4a...first water pipe, 4b...second water pipe, 5
a, 5b...standpipe, 10a, 10b...connection pipe.

Claims (1)

[Scope of Claims] 1. A first water pipe that connects the water intake tank and the ascites, a second water pipe that connects the condenser and the water discharge tank, and a water pipe that branches off from these first and second water pipes, respectively. at least one standpipe provided in the first water pipe, the circulating water is pressurized by a pump provided in the first water pipe and is sent from the water intake tank to the condenser,
In the air-bleeding operation method of a condenser circulating water system, the water is then discharged to the water discharge tank through the second water pipe, the tops of the standpipes of the first and second water pipes and the condenser are communicated with each of the water chambers through connecting pipes, and when starting the condenser, the air stagnant in each of the water chambers, the first and second water pipes, and each of the vertical pipes is removed from the system. filled with circulating water and sent to the water tank,
Further, the condenser circulation is characterized in that after the accumulated air is discharged, the air mixed with the circulating water and flowing into the system is sent to the above-mentioned upright pipes and the above-mentioned communication pipes, and is then discharged to the water discharge tank. How to operate a water system to bleed air. 2. A first water pipe that connects the water intake tank and the condenser, a second water pipe that connects the condenser and the water discharge tank, and at least one water pipe that is branched from each of these first and second water pipes. one standpipe, the circulating water is pressurized by a pump provided in the first water pipe and is sent from the water intake tank to the condenser,
In a condenser circulating water system which is then discharged into the water tank through the second water pipe, the tops of the standpipes of the first and second water pipes and each water chamber of the condenser An air venting device for a condenser circulating water system, characterized in that the two are connected to each other via a connecting pipe.