JPS58876Y2 - Pressurizing device for reactor coolant - Google Patents

Description

[Detailed Description of the Invention] The present invention is a nuclear reactor, particularly a pressurized wooden nuclear reactor (hereinafter referred to as PWR).

) relates to a pressurizing device for adjusting the pressure of a coolant.

In a PWR, the coolant that cools the reactor core and carries the nuclear reaction heat generated within the reactor core out of the reactor vessel to generate steam that ultimately drives the generator drive turbine is used as a cooling agent, which will be described later. Pressure device (hereinafter referred to as pressurizer).

) is maintained at a predetermined pressure.

FIG. 1 shows a schematic structure of a conventional pressurizer.

In Figure 1, a communication pipe 01 is connected to the reactor cooling system (not shown).
A spray device 03, which is connected to a cooling water supply device (not shown), is provided on the top of the container 02, which is connected to the cooling water supply device (not shown).

The lower part of the container 02 is filled with a coolant, usually light water 04,
The upper part of the container 02 is filled with a gas 05 containing steam, and a number of electric heaters 06 are provided penetrating the lower wall of the container 02, and the penetrating portions thereof are sealed.

In the illustrated conventional device, when pressurizing the reactor coolant, light water 04 is heated by electric heater 06 to generate steam, and the amount of steam 05 is increased.

On the other hand, if the pressure of the coolant increases too much and you want to lower it, the spray device 03 will spray out cooling water to remove the gas.
This is done by condensing the vapor in 5 to reduce its volume.

However, the conventional device described above has the following problems.

(a) Since the heat transfer form by the electric heater 06 is pool boiling, a large heat load cannot be achieved.

(b) Since the container 02 is large, sealing a large number of electric heaters 06 through the container requires sophisticated manufacturing technology and consumes a lot of time, which is economically disadvantageous.

(c) During use, the tip of the electric heater 06 is exposed from the surface of the light water 04, and in such a case, if the electric heater 06 is turned on, the electric heater 06
may overheat and burn out, and if you try to avoid this, you will not be able to properly control the pressure.

The present invention has been made in order to solve the above-mentioned problems of the conventional device.

The present invention will be explained below based on the illustrated embodiments.

In FIG. 2, a spray device 3 connected to a cooling water supply device (not shown) is provided on the ceiling of a pressure vessel 2 which is connected to a communication pipe 1 to a reactor cooling system (not shown).

The lower part of the pressure vessel 2 is filled with a coolant, ie, light water 4, and the upper part is filled with a gas 5 containing water vapor.

A rod-shaped electric heater 6 is installed in the container 7 of the heating device 10, which is installed at a lower position than the pressure container 2, and the electric heater 6 is connected to a power source (not shown).

The upper part of the vessel 7 communicates with the gas part of the pressure vessel 2 via a conduit 8, and the lower part of the vessel 7 communicates with the lower part of the pressure vessel 2 via a conduit 9.

The operation of this embodiment having the above-mentioned configuration will be explained.

The operation when lowering the pressure of the coolant is the same as that of the conventional device, so a description thereof will be omitted.

When pressurizing the coolant, the electric heater 6 is energized to heat and boil the light water in the container 7.

As a result, the light water in the container 7 enters a gas-liquid two-phase state, and its specific gravity decreases, creating a difference in specific volume between it and the light water in the pressure container 2, and a natural circulation flow occurs in the direction of the arrow.

The two-phase light water liquid introduced into the pressure vessel 2 from the conduit 8 falls downward and mixes with the light water 4.

The gaseous portion of the two-phase light water, that is, water vapor, is transferred to the pressure vessel 2.
, the pressure of gas 5 increases and pressurizes the reactor coolant.

Due to the natural circulation flow described above, heat transfer between the electric heater 6 and the light water is forced convection heat transfer.

According to this embodiment having the above-described configuration and operation, since light water is flowed around the electric heater 6, the thermal resistance is reduced and the thermal load on the electric heater 6 can be increased, and the heating device 10 is connected to the pressure vessel 2. Because it is located at a lower position, pressure vessel 2
Since the electric heater 6 is always in the light water even if the amount of light water 4 in the tank becomes extremely small, it is possible to prevent the electric heater 6 from being burnt out due to overheating.

Furthermore, since the container 7 is made separate from the large pressure vessel 2, manufacturing such as installation of the electric heater 6 becomes extremely easy, and it is possible to reduce manufacturing costs and improve reliability.

FIG. 3 shows another embodiment of the present invention, which differs from the first embodiment (shown in FIG. 2) in that a circulation pump 11 is provided in the middle of the conduit 9; are the same.

The circulating flow of light water in the direction indicated by the arrow is further ensured by the circulation pump 11, and its operation and effect are the same as those of the first embodiment.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional device, FIG. 2 is a system diagram showing an embodiment of the present invention, and FIG. 3 is a system diagram showing another embodiment of the present invention. 1... Communication pipe, 2... Pressure vessel, 6...
...Electric heater, 7...Container, 8,9.
... Conduit, 10 ... Heating device.

Claims (1)

[Scope of utility model registration request] A pressure vessel whose lower part communicates with the reactor cooling system and which is equipped with a cooling spray device at the upper part, and a conduit that communicates with the lower part and the center of the vessel, respectively, and is located at a relatively low position compared to the vessel. 1. A pressurizing device for a nuclear reactor coolant, comprising an electric heating device.