JP2002174579A - Method and apparatus for measurement of noncondensable gas contained in vapor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus where the measurement of the amount of a noncondensable gas contained in a vapor is automated, and the amount can be measured repeatedly. SOLUTION: The vapor to be measured is condensed, and the amount of the noncondensable gas is measured, on the basis of the pressure of a condensed drain and on the basis of the pressure of the noncondensable gas separated from the condensed drain.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for measuring the amount of non-condensable gas contained in steam.

[0002]

2. Description of the Related Art As is well known, in the sterilization of an object to be sterilized such as a medical instrument and the processing and sterilization of an object to be processed in food processing, steam is brought into direct contact with the object to be sterilized and the object to be processed. Sometimes. And recently, the management of the supplied steam has become important. Traditional steam management
Steam pressure control and temperature control are mainly performed. However, this alone is not enough to manage steam strictly. That is, in the sterilization treatment or the like, non-condensable gas contained in steam may cause sterilization failure or sterilization failure. Therefore, it is necessary to measure the amount of the non-condensable gas contained in the steam and reflect it in the control or record it. In addition, it is necessary to measure and continuously monitor the tendency of the deterioration of the steam quality due to the temporal change due to the operation.

[0003] In the measurement of the amount of non-condensable gas contained in steam, a conventional apparatus and method include, for example, a measurement method (EN285: 1997) specified in European standards.
In this measuring method, the separated non-condensable gas is guided to a 50 ml burette, and the scale engraved on the buret is directly read for measurement, and is a batch-type measuring method. For this reason, it has been difficult to perform automated and repeated measurements. This is because the amount of the non-condensable gas is extremely small, so that it is difficult to perform measurement with a normal flow meter or the like.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus which can automate the measurement of the amount of non-condensable gas contained in steam and can perform the measurement repeatedly. And

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is to condense a vapor to be measured, and to determine the pressure of the condensed drain, The amount of the non-condensable gas is measured based on the pressure of the non-condensable gas separated from the condensed drain.

Further, according to the present invention, the vapor condensing means to be measured, a gas container for storing a non-condensable gas separated from the condensed drain, and a drain container for storing the condensed drain And a calculating unit for calculating the amount of the non-condensable gas based on the pressure in the gas container and the pressure in the drain container.

[0007]

Next, an embodiment of the present invention will be described. The present invention can be suitably implemented in measuring non-condensable gas contained in steam.
Here, the non-condensable gas is a general term for inert gases such as nitrogen, oxygen, and argon existing in the vapor.

A method for measuring a non-condensable gas contained in steam in this embodiment will be described. In measuring the amount of non-condensable gas contained in the vapor, the vapor is first continuously condensed to separate the gas and the drain. This is a method of measuring the amount of the non-condensable gas by performing the separation, detecting the respective pressures, and calculating the volume ratio.

That is, the measurement of the amount of the non-condensable gas can be automated by detecting the respective pressures, and the measurement can be performed repeatedly.

Next, a description will be given of an apparatus to which the method for measuring non-condensable gas contained in steam according to this embodiment is applied. Steam is supplied from the steam generating means. The steam supply pipe is provided with a first temperature sensor for measuring the temperature of the steam and a first pressure sensor for detecting the pressure, and further connected to a condenser for condensing the steam. A gas container for storing the non-condensable gas separated from the condensed drain in a state of a gas column; and a drain container for storing the condensed drain in a state of a liquid column. A calculating unit that calculates a gas amount of the non-condensable gas based on a volume ratio of the non-condensable gas based on the pressure in the drain container.

The gas container is submerged in a water container filled with water in advance, an end of a separation tube is arranged at a lower portion, and the drain is introduced. The gas container has a second temperature sensor and a second pressure sensor. Further, a gas discharge pipe for discharging the stored gas, a gas control valve, and an exhaust pipe are connected to an upper end of the gas container.

The water container is open at an upper position, and is provided with an overflow port at an upper end of a side surface thereof.
An overflow pipe is connected. The overflow pipe is inserted into the drain container.

[0013] In the water container, the drain container may include:
It serves to store the overflow of the drain after the non-condensable gas is separated. The drain container has a third temperature sensor and a third pressure sensor. Furthermore, a drain drain pipe for discharging the stored drain, a drain control valve, and a first discharge pipe are connected to the drain container.

Each of the sensors is connected to an arithmetic unit via a sensor line. Furthermore, each of the control valves is connected to a control unit via a control line.

Next, the operation of the non-condensable gas measuring device having the above-described configuration will be described. The non-condensable gas is separated from the condensed drain on the way and stored in the gas container. Then, the drain after separating the non-condensable gas is stored in the drain container. When the drain is stored in the drain container, the pressure is detected at the same time as the pressure in the gas container is detected. And
Based on the pressure in the gas container and the pressure in the drain container, a gas amount is calculated by the calculation unit based on a volume ratio of the non-condensable gas, and the amount of the non-condensable gas is measured.

When the measurement is completed, both the gas control valve and the drain control valve are opened by the control section, and the state of the measurement is returned to an initial state, that is, so-called reset.
Then, the drain and the non-condensable gas are stored again, and the measurement is performed again, that is, the measurement is repeatedly performed.

Therefore, the measurement of the non-condensable gas can be automated and repeated.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. Here, FIG. 1 is a schematic explanatory view of a non-condensable gas contained in steam measuring device 1 suitable for applying the first embodiment of the present invention.

The non-condensable gas measuring apparatus 1 applied to the first embodiment includes a vapor condensing means 2, a gas container 3 for storing non-condensable gas separated from condensed drain, and a condensed drain. And a calculation unit 32 for calculating the amount of the non-condensable gas based on the pressure in the gas container 3 and the pressure in the drain container 4.

Now, steam is supplied from steam generating means (not shown). The supply of steam to be measured is performed from the first steam supply pipe 5. The system after the first steam supply pipe 5 is a system for measuring the non-condensable gas. The first steam supply pipe 5 is provided with a sensor box 6. The sensor box 6 includes a first temperature sensor 7 and a first pressure sensor 8.
Is provided. A control valve 10 is connected to the second steam supply pipe 9 on the downstream side of the sensor box 6.
A downstream side of the control valve 10 is connected to a third steam supply pipe 11.
2 and a condenser (hereinafter, referred to as “condenser 2”), which is the vapor condensing means 2. A drain pipe 13 for discharging condensed drain is connected to the condenser 2. This drain pipe 13 is connected to an electric conductivity meter 14.
To the separation tube 1 from the electric conductivity meter 14.
5 and connected to a water container 16.

The water container 16 is for separating the non-condensable gas in water. The gas container 3 has a cylindrical shape with a lower part (reference number omitted) opened.
It is submerged in the water container 16 previously filled with water 17. Then, the separation tube 15 is moved to the open lower part.
Is disposed, and the drain is introduced. The gas container 3 includes a second temperature sensor 19 and a second pressure sensor 20. Further, a gas discharge pipe 21 for discharging stored gas, a gas control valve 22, and an exhaust pipe 23 are connected to an upper end portion (symbol omitted) of the gas container 3.

The water container 16 is located at an upper position (reference numerals are omitted).
Is open, and an overflow port 24 is provided at the upper end (not shown) of the side surface. An overflow pipe 25 is connected to the overflow port 24. The overflow pipe 25 is connected to the drain container 4 from the open upper part (reference number omitted) of the drain container 4.
Plugged into.

The drain container 4 has a cylindrical shape with an open upper part, and serves to store the overflow of the drain after the non-condensable gas has been separated in the water container 16. is there. The drain container 4 includes a third temperature sensor 26 and a third pressure sensor 27.
It has. Further, a drain drain pipe 29 for discharging the stored drain 28, a drain control valve 30, and a first discharge pipe 31 are connected to a lower end portion (reference numerals omitted) of the drain container 4.

Then, the sensors 7, 8, 19, 2
The electric conductivity meters 0, 26, 27 and the electric conductivity meter 14 are connected to the calculation unit 32 via sensor lines (not shown and some parts are not shown). Further, each of the control valves 10, 22, 30 is provided with a control line (not shown).
Is connected to the control unit 33 via the.

Next, the operation of the non-condensable gas measuring device 1 having the above configuration will be described. First, as an initial measurement, the drain condensed by the condenser 2 is discharged from the end portion 18 into the water 17 of the water container 16. At this time, the non-condensable gas becomes bubbles (not shown) and is separated from the drain. The separated bubbles are replaced with a liquid part (symbol omitted) inside the gas container 3 submerged in the water 17 and stored in a ceiling part (symbol omitted) in the gas container 3. . Therefore, the amount of the liquid part to be replaced increases according to the amount of the separated non-condensable gas.

Then, the drain from which the non-condensable gas has been separated is stored in the drain container 4 through the overflow pipe 25. After a lapse of a predetermined time in the drain container 4, or when a predetermined amount of drain is stored,
When the pressure is detected by the third pressure sensor 27, the pressure in the gas container 3 is simultaneously detected by the second pressure sensor 2.
0 is detected. Then, based on the pressure in the gas container 3 and the pressure in the drain container 4, the gas amount is calculated by the calculation unit 32 based on the volume ratio of the non-condensable gas, and the amount of the non-condensable gas is calculated. Is measured. put it here,
The amount of the non-condensable gas is approximately three times the amount of the drain 28.
From 10 to 10%.

Further, when the first measurement is completed, the gas control valve 22 and the drain control valve 30 are both opened by a signal from the control section 33 to return the state of the first measurement to the initial state. Reset. That is, after the non-condensable gas in the gas container 3 is discharged, the water 17 is filled with the water 17 again. At this time,
The replenishing means (not shown) replenishes the water container 16 with an amount of water that maintains the water level. On the other hand, the drain 28 in the drain container 4 is also discharged. Further, the data of the operation unit 32 is also reset. Then, the gas control valve 22 and the drain control valve 30 are both closed, the drain and the non-condensable gas are stored again, and the measurement is performed again. That is, the same operation is repeated thereafter to perform the measurement.

Next, a method for measuring a non-condensable gas contained in steam will be described. The vapor to be measured is condensed by the condenser 2, and the amount of the non-condensable gas is calculated based on the pressure of the condensed drain and the pressure of the non-condensable gas separated from the condensed drain. Measure. Then, the measurement of the non-condensable gas contained in the steam can be automated and can be repeated. Further, the measurement of the electric conductivity of the condensed drain can also be performed. Further, instead of the measurement of the electric conductivity, a pH value or the like can be measured.

Next, a second embodiment of the present invention will be described. FIG. 2 is a schematic explanatory view of a steam quality measuring device 34 suitable for applying the present invention. In the second embodiment, the non-condensable gas measuring device 1 of the first embodiment is made to function as a part of the quality measuring device 34, and is incorporated in a device such as a steam sterilizer (not shown). This is an embodiment in which the measurement of the electrical conductivity and the dryness of steam is also performed. In FIG. 2, the same reference numerals are used for the components of the non-condensable gas measuring device 1 described in the first embodiment, and the detailed description is omitted.

First, the configuration of the quality measuring device 34 will be described in detail. The quality measuring device 34 includes the non-condensable gas measuring device 1, and further includes the electric conductivity meter 14 and a dryness measuring device 35.

The supply of the steam to be measured is performed in common from the first steam supply pipe 5, branched off downstream of the control valve 10, and connected to the third steam supply pipe 11 and the fourth steam supply pipe. This is done from tube 36. The third steam supply pipe 1
The downstream side of 1 is a measurement system for the non-condensable gas, and the description is omitted. From the fourth steam supply pipe 36 on the system path after the first steam supply pipe 5, a system for measuring the steam dryness is provided.

The structure of the dryness measuring device 35 used for measuring the dryness of steam will be described in detail. The dryness measuring device 35 includes the first pressure sensor 8, a steam throttling unit 37, an expansion container 38 provided downstream of the throttling unit 37, and a negative pressure less than atmospheric pressure in the expansion container 38. And a vacuum suction unit 39 that functions to bring the state into a state.

The fourth steam supply pipe 36 is provided with a throttle valve (hereinafter referred to as “throttle valve 37”) as the throttle means 37 for wet steam in order toward the downstream side, and the expansion vessel 38.
And the vacuum suction means 39 are provided. The throttle valve 37 has a function of controlling the flow rate of the wet steam. The expansion vessel 38 is for expanding steam, the flow rate of which is controlled by the throttle valve 37, so as to abruptly expand the so-called adiabatic expansion and discharge the vapor, thereby vaporizing the moisture contained in the wet steam. The expansion container 38 is provided with a fourth temperature sensor 40 for detecting a temperature during adiabatic expansion and a fourth pressure sensor 41 for detecting pressure. A second discharge pipe 42 for discharging the discharged high-temperature steam and a heat exchanger 43 for cooling the high-temperature steam are connected to the downstream side of the expansion vessel 38. And the heat exchanger 4
The third discharge pipe 44 and the vacuum suction means 39 are connected to the downstream side of 3. On the downstream side of the vacuum suction means 39,
The fourth discharge pipe 45 is connected. This fourth discharge pipe 45
Is led to an outdoor or the like (not shown).

The vacuum suction means 39 is connected to the expansion container 3.
The inside of the pump 8 is evacuated to make the inside thereof a negative pressure lower than the atmospheric pressure. For example, a water ring vacuum pump (hereinafter, referred to as “vacuum pump 39”) is used.

Each of the sensors 40 and 41 is connected to the arithmetic unit 32 via a sensor line (not shown).
Is connected to Further, the vacuum pump 39 is connected to the control unit 33 via a control line (not shown).

Next, the operation of the dryness measuring device 35 having the above configuration will be described. Wet steam is introduced from the throttle valve 37 into the expansion vessel 38, and the inside of the expansion vessel 38 is brought into a negative pressure state lower than the atmospheric pressure by the vacuum pump 39. By setting the inside of the expansion container 38 to a negative pressure state lower than the atmospheric pressure, the measurement range of the dryness can be expanded. That is, even if the steam contains a large amount of water, it is possible to vaporize more water to be released under a state near the atmospheric pressure. And, the fourth discharge pipe 45
This is for discharging the measured steam to the outside of the room (not shown).

Next, a method for measuring the dryness of steam will be described. Steam is introduced from the throttle valve 37 into the expansion vessel 38, and the inside of the expansion vessel 38 is brought into a negative pressure state lower than the atmospheric pressure by the vacuum pump 39. Then, the steam is discharged into the expansion container 38 and adiabatically expanded, and the dryness is measured in this state. That is, based on the signals from the first pressure sensor 8, the fourth pressure sensor 41, and the fourth temperature sensor 40, the calculation is performed by the calculation unit 32 to measure the dryness of the steam.

In this way, the measurement of the non-condensable gas and the various qualities of the vapor can be performed in a state where the non-condensable gas is incorporated in a sterilizer (not shown) or a processing machine (not shown).

[0039]

According to the present invention, the measurement of the non-condensable gas contained in the steam can be automated, and the measurement can be repeated more. Can measure and manage quality.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a measuring device for non-condensable gas contained in steam to which an embodiment of the present invention is applied.

FIG. 2 is a schematic explanatory view of a steam quality measuring apparatus suitable for applying the present invention.

[Explanation of symbols]

 2 Condensing means (condenser) 3 Gas container 4 Drain container

Claims (2)

[Claims] 1. Condensing a vapor to be measured and measuring an amount of the non-condensable gas based on a pressure of the condensed drain and a pressure of the non-condensable gas separated from the condensed drain. A method for measuring non-condensable gas contained in steam. 2. A condensing means 2 for vapor to be measured, a gas container 3 for storing non-condensable gas separated from condensed drain, and a drain container 4 for storing the condensed drain. The pressure in the container 3 and the pressure in the drain container 4
A measuring unit for calculating the amount of the non-condensable gas based on the pressure of the non-condensable gas.