JPS61241693A - Make-up water controller for nuclear reactor of nuclear power plant - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a nuclear reactor of a nuclear power plant in which a pure water supply system and a boric acid water supply system are connected to the primary cooling circulation system of the nuclear power plant via a volume control tank. This invention relates to a make-up water control device.

(Prior Art) A nuclear reactor is operated with fuel in it for a predetermined period (for example, about one year), and a predetermined nuclear reaction (reactivity) must be obtained even at the end of that period. uranium-23
For materials such as No. 5, which cease to be fissile materials due to nuclear reactions (combustion), a larger amount of fissile material than is required for the reaction is introduced at the beginning of the period, so at the beginning of the period, the nuclear reaction is suppressed and only one reaction Boric acid is used in pressurized water reactors for this reason, but the combustion
As it progresses day by day, the boron must be changed to take this into account.

A conventional example of a reactor make-up water control system that adjusts the concentration of boric acid water as described above is explained with reference to FIG. 3. (g) is a pure water make-up system, (&) is a boric acid water supply system, and (6) is the pure The pure water flow control valve installed in the water supply system (,), (d) is the boron water flow control valve installed in the penta-acid water supply system (b), (#) is the boric acid mixer, (A is the same) The make-up water flow meter installed downstream of the boric acid mixer (1), (g) the boric acid water flow meter installed downstream of the boric acid water flow control valve (d), and the boric acid water flow meter installed downstream of the boric acid mixer (1); The makeup water flow rate detection signal from the makeup water flow meter (1) and the deionized water flow rate set value signal from the makeup water flow rate setting device (not shown) are connected to the makeup water flow rate controller (not shown) through piping connected to the material circulation system. (not shown), and the control signal processed here is sent to the pure water flow control valve (1), which controls the opening degree of the pure water flow control valve (c). The pure water stored in the boric acid mixer (#) is sent to the boric acid mixer (#), and the boric acid flow rate detection signal from the boric acid water flow meter (g) and the boric acid water flow rate from the boric acid water flow rate setting device (not shown) are sent to the boric acid mixer (#). The set value signal is sent to the hydration flow rate controller (not shown), and the control signal processed here is sent to the hydration flow rate control valve (d).
By controlling the opening of the boric water flow rate control valve (d), the boric acid water of a certain concentration stored in the boric water tank (not shown) is sent to the boric acid mixer (-), where the pure boric acid water is The make-up water obtained by mixing with water is supplied to the primary coolant circulation system via a piping body to change the boron concentration in the primary coolant circulation system.

(Problems to be Solved by the Invention) In pressurized water reactors, as already mentioned, it is necessary to change the boron concentration in consideration of the daily progress of combustion.
Conventionally, the primary coolant flowing through the primary coolant circulation system was sampled from the negative point of operation, the mixing ratio was calculated, and the make-up water flow rate setting device and boric acid water were adjusted based on the resulting output value. The operator had to change the □ set value of the flow rate setting device, which placed a considerable burden on the operator.

The present invention addresses the above-mentioned problems, and is intended to solve the problem in a nuclear power plant in which a pure water replenishment system and a boric acid water supply system are connected to the primary coolant circulation system of the nuclear power plant via a volume control tank. Boron concentration setting device determined by the progress and operating conditions.

a boric acid concentration detector for detecting the boric acid concentration in the primary coolant circulation system; a water level detector for detecting the water level in the volume control tank; the boron concentration setting device; the boric acid concentration detector; and the water level detector. A control signal obtained by processing the output of A reactor make-up water control device for a nuclear power plant characterized by comprising a controller for controlling flow rate, the purpose of which is to be able to automatically change boron concentration. The object of the present invention is to provide a reactor make-up water control system for a nuclear power plant that can reduce the burden on operators.

(Means for Solving the Problems) The present invention is directed to an atomic plan in which a pure water supply system and a boric acid water supply system are connected to the primary coolant circulation system of an atomic plant via a volume control tank as described above. , a boron concentration setting device whose set value is determined depending on the progress of combustion and operating conditions; a diffuseness detector that detects the boric acid concentration in the primary coolant circulation system; and a water level that detects the water level of the volume control tank. A pure water flow rate control valve provided in the pure water supply system and a control signal obtained by processing the outputs of the detector, the boron concentration setting device, the boric acid concentration detector, and the water level detector, and the boric acid It is equipped with a boron water flow rate control valve installed in the water supply system and a controller that controls the flow rate of pure water and boric acid water sent to the water supply system, and changes in boron concentration are performed automatically. is reduced.

(Embodiment) Next, the reactor make-up water control system for a nuclear power plant according to the present invention will be explained using an embodiment shown in Fig. 1.2.(1) in Fig. 1 is a pure water tank storing pure water. , (2) is a pure water pump, (3) is a pure water flow control valve, (4) is a boric acid water tank that stores boric acid water at a certain concentration, (5) is a boric acid water pump, and (6) is a boric acid water Flowmeter, (7) is the boric acid mixer, (9) is the make-up water flow meter, (IQ is the volume control tank that stores make-up water, (Iυ is the same volume control tank 4) Piping extending to the primary coolant circulation system, Q3 is the return line of the primary coolant circulation system, a is the water level detector of the same volume control tank 4, (12') is the water level controller of the same volume control tank CIQ , the α force is the return line of the primary coolant circulation system (the pot installed in 13, the a stage is the boric acid concentration detector, and the boric acid concentration detector α1 is the above-mentioned hole). The boric acid concentration in the primary coolant is detected based on the amount of neutrons absorbed at that time, and the results are displayed on the instrument panel.
is the water level control valve of the volume control tank QO, 0η is the coolant storage tank (not shown), and the water level of the make-up water in the volume control tank Ql is detected by the water level detector α, which is obtained at that time. A water level detection signal is sent to the water level controller (12'), and when the water level of the volume control tank Ql decreases, a control signal is sent from the water level controller (12') to the controller (20) described later to control the pure water flow rate. The valve (3) and the boric acid water flow rate controller (force) are sent to each flow rate control valve (3) (force opening degree is controlled to supply make-up water to the current concentration of boric acid in the primary coolant circulation system. A control signal is sent to the volume control tank. Also, if the volume control tank QOI becomes high, a control signal is sent to the water level controller (12).
) is sent from the water level control valve (le) to the water level control valve (I
Q is opened so that make-up water in one volume control tank (101) is sent to the coolant storage tank Qη.

Also, the symbol a in Figure 1.2 is the boron concentration setting device (the set value is determined by the progress of combustion and the operating conditions).
, ← 1 is off, automatic, a replenishment permission switch equipped with a human push button, ■ is processing the outputs of the boron concentration setting device U, the boric acid concentration detector (151, and the water level detector α). The obtained control signal is sent to a pure water flow rate control valve (3) provided in the pure water supply system and a boric acid water flow rate controller (7) provided in the boric acid water supply system to control the flow rates of pure water and boric acid water. The controller is equipped with an integrator (2υ), an arithmetic unit G!21 (251), a comparator (2F), and a make-up water flow rate setting device (25'), In the container (21),
The boric acid water flow rate detection signal from the boric acid water flow meter (6) and the make-up water flow rate detection signal from the make-up water flow meter (9) are used to separately integrate the amount of boric acid (A1) and the amount of pure water (A2). It is supposed to be done. In addition, the arithmetic unit (221) uses the boric acid concentration detector signal (current boric acid concentration detection signal of the primary coolant circulation system) from the boric acid concentration detector (15) and the boron concentration from the boron concentration setting device α mark. The deviation from the set signal is determined, and the amount of boric acid added (B1) and the amount of pure water added (B2) are calculated from the results.v
The comparator (c) compares the boric acid amount (A1) signal from the integrator Qυ with the boric acid addition amount (B1) signal from the computer (company) and determines whether AI=B1. For example, send a control permission signal to close the valve to the boric acid water flow rate controller (7), and if Al (B1), send the control permission signal to the boric acid water flow rate controller (7).
) to send a control permission signal to open the valve. Further, the comparator C2 uses the pure water amount signal (A2) from the integrator Cυ and the pure water addition amount (B2) from the arithmetic unit (24).
) signal and if it is s A2-B2, sends a control permission signal to close the valve to the pure water flow rate control valve (3) %A2<B
If it is 2, a control permission signal for opening the valve is sent to the pure water flow rate control valve (3). In addition, the amount of dilution of the primary coolant is determined by the make-up water flow rate set value signal from the make-up water flow rate setting device (25' in two countries) and the boron concentration setting signal from the boron concentration setting device α barrel. , calculates the concentration amount, and sends the result as a water sprinkler flow rate set value signal. Also, the wire outside the above controller wire is the make-up water flow rate setting device, @ is the water spray amount setting device, (H) ) is a pure water flow rate controller, 翺 is a boric acid water flow rate controller, and either one of the make-up water flow rate setting device - and the make-up water flow rate setting device (25') can be selectively used as the pure water flow rate controller (c). When the contacts to connect and the contacts to selectively connect either the boric acid water flow rate setting device (c) or the calculator c!kiku to the boric acid water flow rate controller are in the positions shown, ) and the make-up water flow rate setting value signal from the make-up water flow rate setting device (c) are sent to the pure water flow rate controller (c), where the control signal obtained by processing is purified. Send the pure water stored in the pure water tank (not shown) to the boric acid mixer (8) by controlling the opening degree of the pure water flow control valve (3), In addition, the boric acid water flow rate detection signal from the boric acid water flow meter (6) and the boric acid water flow rate set value signal from the boric acid water flow rate setting device (5) are sent to the boric acid water flow rate controller (c), where they are processed. The obtained control signal is sent to the penta-acid water flow rate control valve (7), and the opening degree of the boric acid water flow rate controller (7) is controlled to control the boric acid water at a constant concentration stored in the boric acid water tank (4). is sent to the boric acid mixer (8), where the make-up water obtained by mixing with the pure water is sent to the primary coolant circulation system via the volume control tank holder.The above-mentioned contacts are , when a low water level control signal is sent from the water level controller (12') of the volume control tank QQ, and when the replenishment permission switch 4 is switched to automatic.

Makeup water flow rate setting device (a) and irrigation water flow rate setting device (5)
is separated.

(Function) Next, the function of the reactor make-up water control system for the nuclear power plant will be explained. This control device handles approximately 2QOOOII of pure water sent from the pure water tank (1) through the pure water pump (2).
A boric acid water tank (which stores In (constant concentration) boric acid water)
4) through the boric acid water pump (5) and fed to the boric acid mixer (8) and mixed,
The make-up water obtained here is transferred from volume control tank a [to pipe 0
By adding boric acid at a constant flow rate to the primary coolant circulation system via 1), it has the effect of controlling the concentration of boric acid in the primary coolant circulation system to a desired value. In addition, the primary coolant circulation system constitutes a closed loop, and when the temperature of the primary coolant changes,
As the volume increases or decreases, the water level in the volume control tank OQ changes, but in order to maintain the water level in the volume control tank within a certain range, if the water level rises, the excess water is transferred to the water level control valve (
The coolant is transferred to the coolant storage tank (17) via the three-way valve (1G), and when the water level drops, the controller of this controller replenishes the shortage to the volume control tank QOI.

When reducing the degree of desertification of the primary cooling circulation system,
By opening the pure water flow control valve (3) and adding a certain amount of pure water from the pure water tank (1), the degree of desertification of the primary coolant circulation system is reduced. In addition, when increasing the degree of desertification of the primary coolant circulation system, open the boric acid flow control valve (7) and add a certain amount of high concentration boric acid water from the boric acid water tank (3). , increasing the degree of desertification of the primary coolant circulation system. In addition, when the water level in the volume control tank (101) drops, each flow control valve (3) is opened to add boric acid water of the same degree as the primary coolant circulation system, and the pure water and boric acid water are After mixing, it is added to the primary coolant circulation system at a constant flow rate.Also, the degree of indistinctness of the primary coolant circulation system is determined by adding the bottle on the return line side of the primary coolant circulation system.
14) The degree of desertion obtained by measuring the coolant retained in the coolant or the sampled coolant is used as the standard for adjusting the degree of desertity of the primary coolant. The present invention automates the headway desert degree adjustment in the above-mentioned reactor make-up water control system. That is, in the block diagram of the primary coolant desert direct control shown in FIG. 2, the digital part within the dashed line indicates the computer part by direct digital control (computer control), and the other parts are the conventional ones. analog instrument,
Shows switches, etc. When lowering or increasing the degree of desertification of the primary coolant circulation system, set the degree of desertity of the primary coolant circulation system after the decrease or increase in the degree of desertity setting device a8). , the target amount of water to be added and the amount of pure water to be added are calculated by the calculator. In addition, since the replenishment permission switch 0 is taken prisoner and the integrator Cυ is reset, the comparator (C) or (F) is activated, and the make-up water flow rate setting device (C) and the water spray amount setting device (F) are activated. ) The flow rate control valves (3) and (7) are controlled by the set values. In addition, the integrator 0υ integrates the flow detection values of the boron sprinkler flowmeter (6) and makeup water flowmeter, calculates the amount of pure water and the amount of boric acid, and calculates the amount of pure water and boric acid.
221 automatically calculates the target value, and if the primary coolant desert degree reaches the target value, the conditions of the comparator (c) are not satisfied, and the flow control valves (3) and (7) closes, and the distance adjustment operation is completed.

In addition, if the replenishment permission switch is set to "auto" and the water level of the volume control tank (101) falls below the set water level, the water level controller (12') of the volume control tank (101) will operate, and the flow rate control valve (3) will operate. (7) becomes controllable. At this time, the flow rate control valve (3) is controlled by the set value of the make-up water flow rate setting device (25'), and the flow rate control valve (7) is controlled by the calculator (c). Controlled by the calculated set value, boric acid water is automatically replenished until the water level in the volume control tank Q (1) returns.

(Effects of the Invention) The present invention is applicable to a nuclear power plant in which a pure water supply system and a borax supply system are connected to the primary coolant circulation system of the nuclear power plant via a volume control tank as described above. a distance setting device determined by the progress of the vehicle and driving conditions;
a boric acid concentration detector for detecting the boric acid concentration in the primary coolant circulation system; a water level detector for detecting the water level in the volume control tank; A control signal obtained by processing the output from the device is sent to a pure water flow control valve provided in the pure water supply system and a water spray flow control valve provided in the water supply system to supply pure water and water. It is equipped with a controller that controls the flow rate of
The degree of visibility can be changed automatically, which has the effect of reducing the burden on the operator.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of drawings]

Fig. 1 is a system diagram showing one embodiment of the reactor make-up water control system for a nuclear power plant according to the present invention, Fig. 2 is its control block diagram, and Fig. 3 is a conventional reactor make-up water control system for a nuclear power plant. It is a system diagram of a device. (3)...Pure water flow rate control valve, (Power...Sprinkling flow rate control valve, (1...Water level detector, aω...Boric acid concentration detector, (IEfl...Boric acid concentration detector) Degree setting device, wire...
・Controller. Sub-agents: 2 patent attorneys and non-Kaimoto important literary figures

Claims (1)

[Claims] In a nuclear power plant where a pure water supply system and a boric acid water supply system are connected to the primary coolant circulation system of the nuclear power plant via a volume control tank, a boron concentration setting device and a boron concentration setting device whose set value is determined depending on the progress of combustion and operating conditions are used. , a boric acid concentration detector for detecting the boron concentration in the primary coolant circulation system, a water level detector for detecting the water level in the volume control tank, the boron concentration setting device, the boron concentration detector, and the boron concentration detector. A control signal obtained by processing the output from the water level detector is sent to a pure water flow control valve provided in the pure water supply system and a boric acid water flow control valve provided in the boric acid water supply system. A reactor make-up water control device for a nuclear power plant, comprising: a controller for controlling the flow rate of boric acid water.