JP2011002396A - Hydrogen concentration measuring system, and method for calibrating hydrogen concentration measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize tank equipment for storing calibration gas.SOLUTION: This hydrogen concentration measuring system, equipped with a measuring target device through which gas flows, a hydrogen concentration measuring instrument for measuring the concentration of hydrogen in the gas and a measuring system for connecting the measuring target device and the hydrogen concentration measuring instrument, includes a calibration gas system for supplying the calibration gas from the upstream side of the hydrogen concentration measuring instrument. The calibration gas supplied to the hydrogen concentration measuring instrument is recovered from the downstream side of the hydrogen concentration measuring instrument to be returned to the calibration gas system. By this constitution, the tank equipment for storing the calibration gas is miniaturized.

Description

  The present invention relates to a hydrogen concentration measuring system and a hydrogen concentration measuring device calibration method.

  Patent Document 1 discloses a method for calibrating a hydrogen detector in a gas component monitoring device of a nuclear power plant. The calibration gas (hydrogen standard gas) used when calibrating the hydrogen detector is used for the calibration test of the hydrogen detector, then supplied to the hydrogen storage tank to reduce the hydrogen concentration of the calibration gas, and stored in the reactor. Return to container.

Japanese Patent Laid-Open No. 9-21784

  In the calibration test of the hydrogen detector, it is necessary to keep the calibration gas flowing through the hydrogen detector for a certain period of time in order to stabilize the indicated value of the hydrogen detector by the calibration gas. Therefore, a large amount of calibration gas is consumed, and the capacity of the tank that stores the calibration gas increases. Therefore, there has been a problem that the equipment is increased in size.

  An object of the present invention is to reduce the size of a tank facility for storing calibration gas.

  The present invention includes a calibration gas system for supplying calibration gas from the upstream side of the hydrogen concentration measuring instrument, and the calibration gas supplied to the hydrogen concentration measuring instrument is recovered from the downstream side of the hydrogen concentration measuring instrument and is supplied to the calibration gas system. It is returned.

  According to the present invention, it is possible to reduce the size of a tank facility for storing calibration gas.

It is a figure which shows the hydrogen concentration measurement system in the gaseous waste processing equipment of a nuclear power plant. It is a figure which shows the valve opening / closing state in the case of performing zero gas calibration. It is a figure which shows the valve opening / closing situation in performing span gas calibration.

  FIG. 1 shows a hydrogen concentration measurement system in a gaseous waste treatment facility of a nuclear power plant. In the nuclear power plant, the nuclear reactor 1 converts water into steam, rotates the turbine 2 with steam, and generates power with the generator 4. The steam that has driven the turbine 2 returns to water in the condenser 3 and is supplied to the nuclear reactor 1 again.

  The gaseous waste treatment facility 5 continuously extracts hydrogen, oxygen, and the like contained in the gas flowing through the condenser 3, converts the oxygen and hydrogen contained in the gas into water vapor by a catalytic reaction, and the hydrogen concentration is less than the flammable limit. To. Further, the gas is cooled to condense most of the water vapor in the gas, and the moisture is condensed and removed. Further, after the gas is adsorbed on the activated carbon for a certain period and the radioactivity is attenuated to an extent that does not affect the environment, the treated gas is released into the atmosphere.

  The hydrogen concentration measurement system 100 includes a gas waste treatment facility 5, a hydrogen concentration measurement device 6, and a calibration gas device 7 that are measurement targets. The hydrogen concentration measuring device 6 is a device for confirming the hydrogen concentration in the gaseous waste treatment facility 5. The calibration gas device 7 is a device for calibrating the hydrogen concentration measuring device 14 included in the hydrogen concentration measuring device 6.

  In this embodiment, the hydrogen concentration measuring device 6 determines the hydrogen concentration in the gas by the hydrogen concentration measuring device 14, the measurement system 25 connecting the gas waste treatment facility 5 and the hydrogen concentration measuring device 14, and the hydrogen concentration measuring device 14. After the measurement, a pipe 24 for returning the gas to the condenser 3, a valve 8 for adjusting the flow rate of the gas flowing through the measurement system 25, and a valve 9 for adjusting the flow rate of the gas flowing through the pipe 24 are provided. Further, on the upstream side of the hydrogen concentration measuring instrument 14, a first calibration gas system 26 that supplies zero gas, which is a first calibration gas, to the hydrogen concentration measuring instrument 14, and a span gas, which is a second calibration gas, are measured for hydrogen concentration. A second calibration gas system 27 for supplying to the vessel 14 is connected. The first calibration gas system 26 and the second calibration gas system 27 include valves 10 and 11 for adjusting the supply amount of the calibration gas, respectively. A first calibration gas system 26 is connected to the downstream side of the hydrogen concentration measuring instrument 14 in order to recover the first calibration gas supplied to the hydrogen concentration measuring instrument 14. Similarly, a second calibration gas system 27 is also connected to recover the second calibration gas supplied to the hydrogen concentration meter 14.

  The first calibration gas system 26 includes a valve 10, a hydrogen concentration measuring device 19 a, a tank 22, a check valve 23, a pump 17, and a tank 15 from the upstream side. The second calibration gas system 27 includes a valve 11, a hydrogen concentration measuring device 19, a tank 20, a check valve 21, a pump 18, and a tank 16 from the upstream side. Further, a control panel 30 for controlling the hydrogen concentration measuring device 6 and the calibration gas device 7 is provided.

  FIG. 1 shows a valve opening / closing state in the case of measuring the gas hydrogen concentration in the measurement target apparatus. Valves in the “open” state are outlined, and valves in the “closed” state are shown in black. Valves 8 and 9 are opened, and valves 10, 11, 12, and 13 are closed. Since the gas pressure in the measurement system 25 is lower than the gas pressure in the pipe 24, the gas in the measurement system 25 flows through the valve 8, the hydrogen concentration measuring instrument 14, the valve 9, and the pipe 24. The hydrogen concentration in the gas is measured by the hydrogen concentration meter 14.

  Moreover, in order to confirm the soundness of the hydrogen concentration measuring device 14, calibration with a calibration gas is periodically performed. Calibration gas is supplied from the calibration gas device 7. This calibration is performed using zero gas and span gas. Zero gas is a calibration gas used for calibrating the minimum scale value of the hydrogen concentration measuring instrument 14, and nitrogen gas or the like is used. The span gas is a calibration gas used for calibrating the scale value near the maximum scale value of the hydrogen concentration measuring instrument 14, and a hydrogen concentration gas close to the maximum scale value is used. It is also possible to use a midpoint gas. The midpoint gas is a calibration gas used to calibrate a scale value between the minimum scale value and the maximum scale value of the hydrogen concentration measuring instrument 14. In FIG. 1, the midpoint gas is omitted.

  The calibration method of the hydrogen concentration measuring instrument 14 performs zero adjustment after flowing zero gas for a certain period of time and the indicated value of the hydrogen concentration measuring instrument 14 is stabilized. Next, the span gas is allowed to flow for a certain period of time, and the span adjustment is performed after the indicated value of the hydrogen concentration measuring instrument 14 is stabilized. Repeat zero adjustment and span adjustment as necessary, and confirm that the zero and span instructions match within the specified reproducibility.

  Perform zero gas calibration and span gas calibration according to the following procedure.

  When performing zero gas calibration, the control panel 30 transmits a control signal 32 to the valve based on the measurement signal 31 indicating the hydrogen concentration of the zero gas detected by the hydrogen concentration measuring device 19a. FIG. 2 is a diagram illustrating a valve opening / closing state when zero gas calibration is performed. At this time, the valves 10 and 12 are set to “open”, and the valves 8, 9, 11, and 13 are set to “closed”. Further, the pumps 17 and 18 are in a “stop” state. Since the gas pressure in the tank 15 is lower than the gas pressure in the tank 22, the zero gas in the tank 22 flows through the valve 10, the hydrogen concentration measuring device 14, and the valve 12 and is stored in the tank 15. Zero gas is flown for a certain period of time, and after confirming that the instruction of the hydrogen concentration measuring instrument 14 is stable in the vicinity of zero, zero adjustment of the hydrogen concentration measuring instrument 14 is performed. Zero gas calibration is performed while checking the hydrogen concentration of the zero gas with the hydrogen concentration measuring device 19a.

  Next, the span adjustment is performed with the span gas. FIG. 3 is a diagram illustrating a valve opening / closing state when span gas calibration is performed. In the span gas calibration, the control panel 30 transmits the control signal 32 based on the measurement signal 31 indicating the hydrogen concentration of the span gas detected by the hydrogen concentration measuring device 19, and the valves 11, 13 are opened, and the valves 8, 9, 10 are used. , 12 are “closed”. The pumps 17 and 18 are “stopped”. Since the gas pressure in the tank 16 is lower than the gas pressure in the tank 20, the span gas in the tank 20 flows through the valve 11, the hydrogen concentration measuring instrument 14, and the valve 13 and is stored in the tank 16. The span gas is allowed to flow for a certain period of time, and after confirming that the instruction of the hydrogen concentration measuring instrument 14 is stable, the span of the hydrogen concentration measuring instrument 14 is adjusted. The span gas calibration is performed while checking the span gas with the hydrogen concentration measuring device 19.

  Next, the zero gas is returned from the tank 15 to the tank 22. This returning step is performed in the measurement state of FIG. In the measurement state, the valves 8 and 9 are set to “open” and the valves 10, 11, 12 and 13 are set to “closed” by the control signal 32 from the control panel 30. In the measurement state, the zero gas stored in the tank 15 is sucked by the pump 17 and returned to the tank 22 via the check valve 23. The pump 17 is activated by a control signal 32 from the control panel 30. In addition, the zero gas return step is performed at an arbitrary time in the measurement state.

  The span gas is also returned from the tank 16 to the tank 20. During the measurement state, the span gas stored in the tank 16 is sucked by the pump 18 and returned to the tank 20 via the check valve 21. The pump 18 is also activated by a control signal 32 from the control panel 30. The span gas is returned to the tank 20 at an arbitrary time in the measurement state. As described above, the zero gas return process and the span gas return process are performed by starting the pump 17 or the pump 18 for a predetermined time by the control signal 32 from the control panel 30. You may carry out simultaneously.

  As described above, zero gas calibration and span gas calibration can be performed again by returning the zero gas and span gas to the tanks 22 and 20, respectively.

  Thus, the present embodiment includes a calibration gas system that supplies calibration gas from the upstream side of the hydrogen concentration measuring instrument 14, and the calibration gas supplied to the hydrogen concentration measuring instrument 14 is downstream of the hydrogen concentration measuring instrument 14. And returned to the calibration gas system. Therefore, it is possible to prevent the calibration gas from being discharged to the gaseous waste treatment facility 5, and to reduce the size of the tank facility for storing the calibration gas.

  Further, in this embodiment, the two calibration gas systems supplying the first calibration gas and the second calibration gas from the upstream side of the hydrogen concentration measuring device, the first calibration gas supplied to the hydrogen concentration measuring device, and The second calibration gas is collected from the downstream side of the hydrogen concentration measuring device and returned to the two calibration gas systems. Therefore, even when two or more types of calibration gases (for example, span gas and zero gas) are used, two types of calibration gases can be switched and used, so that mixing of different types of calibration gases can be suppressed.

  Thus, the calibration gas supplied from the upstream side of the hydrogen concentration measuring instrument 14 is recovered from the downstream side of the hydrogen concentration measuring instrument 14 by performing the zero gas calibration, the span gas calibration, the zero gas returning process, and the span gas returning process. And returned to the calibration gas system again. Therefore, the calibration gas can be circulated and used. In this embodiment, the gas used in the calibration is returned again to zero gas and span gas and used. Therefore, consumption of the calibration gas can be suppressed, and the capacity of the tank that stores the calibration gas can be reduced. In addition, by circulating the calibration gas, unnecessary zero gas and span gas do not need to flow to the waste treatment facility.

  It can be applied to facilities using hydrogen concentration measuring instruments at nuclear power plants.

DESCRIPTION OF SYMBOLS 1 Reactor 2 Turbine 3 Condenser 4 Generator 5 Gas waste disposal facility 6 Hydrogen concentration measuring device 7 Calibration gas device 8, 9, 10, 11, 12, 13 Valves 14, 19, 19a Hydrogen concentration measuring device 15, 16, 20, 22 Tanks 17, 18 Pumps 21, 23 Check valve 24 Piping 25 Measurement system 26 First calibration gas system 27 Second calibration gas system 30 Control panel 31 Measurement signal 32 Control signal

Claims (3)

A measurement target device through which gas flows;
A hydrogen concentration meter for measuring the hydrogen concentration in the gas;
A hydrogen concentration measurement system comprising a measurement system for connecting the measurement target device and the hydrogen concentration measuring instrument,
A calibration gas system for supplying calibration gas from the upstream side of the hydrogen concentration measuring instrument;
The calibration gas supplied to the hydrogen concentration measuring device is recovered from the downstream side of the hydrogen concentration measuring device and returned to the calibration gas system. A measurement target device through which gas flows;
A hydrogen concentration meter for measuring the hydrogen concentration in the gas;
A hydrogen concentration measurement system comprising a measurement system for connecting the measurement target device and the hydrogen concentration measuring instrument,
Two calibration gas systems for supplying a first calibration gas and a second calibration gas from the upstream side of the hydrogen concentration measuring instrument;
The first calibration gas and the second calibration gas supplied to the hydrogen concentration measuring device are respectively collected from the downstream side of the hydrogen concentration measuring device and returned to the two calibration gas systems. To measure hydrogen concentration. A measurement target device through which gas flows;
A hydrogen concentration meter for measuring the hydrogen concentration in the gas;
A method for calibrating a hydrogen concentration measuring instrument comprising a measurement system for connecting the device to be measured and the hydrogen concentration measuring instrument,
Supply calibration gas from the upstream side of the hydrogen concentration measuring instrument,
A calibration method for a hydrogen concentration meter, wherein the calibration gas supplied to the hydrogen concentration meter is recovered from the downstream side of the hydrogen concentration meter and returned to the calibration gas system.

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