JP2005326273A - Calibration gas generation quantity measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continuously and easily measure the weight of a calibration gas generation tube without being taken out of a thermostat bath. <P>SOLUTION: This device for continuously generating the calibration gas while keeping the calibration gas generation tube in a thermostat state and measuring the quantity of the generated calibration gas, comprises a holder on which the calibration gas generation tube is arranged in a sealed state; the thermostat bath in which the holder is arranged; and a weight meter. The weight meter is connected to the calibration gas generation tube through a connecting member, and the calibration gas generation tube is set in the holder so as to be floated, and the weight of the calibration gas generation tube is continuously measured to measure the generation quantity of the calibration gas. According to this, since the weight of the calibration gas generation tube can be continuously and easily measured even if it is taken out of the thermostat bath, the measurement can be performed in a stable state without requiring much labor hour and time. Therefore, the work efficiency can be improved without causing an error or having influence on the health of a measuring person. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is, for example, the amount of calibration gas generated for use as a calibration gas by continuously generating various gases such as acetaldehyde, ammonia, ethanol, ethyl acetate, dichloromethane, nitrogen dioxide or hydrogen sulfide at a minute concentration. Specifically, the present invention relates to a calibration gas generation amount measurement device that continuously measures the weight of the calibration gas generation tube that generates the various gases to measure the generation amount of the calibration gas. is there.

  Conventionally, various calibration gases (standard gases) used for comparison of gases to measure the concentration of gases such as acetaldehyde, ammonia, ethanol, ethyl acetate, dichloromethane, nitrogen dioxide or hydrogen sulfide are continuously generated. For example, a calibration gas generation tube such as a permeation tube or a diffusion tube is disposed in a device such as a permeator (standard gas generator (constant temperature bath)), and the calibration gas generation tube is in a constant temperature state. Thus, the calibration gas is generated.

As a technique for continuously generating gas using this permeator, for example, an extremely low concentration odor gas continuously generated at a constant concentration using a permeator is pre-enclosed with a deodorant sample. After injecting a certain amount into the odor gas contact bag through a Teflon (registered trademark) tube, sealing it, leaving it for a certain period of time to deodorize, and then introducing the residual gas in the odor gas contact bag into the gas adsorption tube A method for measuring the deodorizing effect of a deodorant comprising adsorbing an adsorbent in an adsorbing tube, then thermally desorbing the gas adsorbed on the adsorbent, and then analyzing the gas with a gas chromatograph mass spectrometer There is.
JP 2003-75418 A

  In the known technique of this Patent Document 1, the deodorizing effect of the deodorant material is measured with high accuracy by using an extremely low concentration odor gas continuously generated at a constant concentration using a permeator. When measuring the concentration (generation amount) of the odorous gas, after adsorbing a nonenal standard solution of various concentrations to these adsorbents, it is desorbed with a thermal desorption device, and the concentration is measured with a gas chromatograph mass spectrometer. The peak area, which is a measure of the above, is measured.

  As described above, when measuring the generation amount, permeation rate, diffusion rate, etc., of various calibration gases generated using a permeator, the weight of the calibration gas generation tube before use is generally determined first. Measure in advance, arrange the calibration gas generation tube in the permeator to generate various gases, take out the calibration gas generation tube disposed in the permeator at regular intervals, and Measure the weight of the gas generation tube, and determine the generation amount, permeation rate, diffusion rate, etc. from the difference in weight loss between the calibration gas generation tube after generation of the various gases and the calibration gas generation tube before use. I'm calculating.

  And when measuring the weight of the calibration gas generation tube taken out from the permeator, in order to reduce the measurement error, the gas of the same type as the gas generated from the calibration gas generation tube is filled That is, the weight is measured in the same space as in the permeator.

  However, the weight of the calibration gas generation tube is measured when the generation amount, permeation rate, diffusion rate, etc. of various calibration gases generated using a permeator (constant temperature bath) are measured as in the prior art. Since the calibration gas generation tube must be taken out of the permeator and measured every time the measurement is performed, the measurement takes a lot of labor and time and causes a measurement error. It has the problem that it cannot be measured.

  Also, when measuring the weight of the calibration gas generating tube taken out from the permeator, the weight is measured in the same space as in the permeator, but depending on the type of gas to be measured Since there are toxic gases, corrosive gases, and the like, there is a risk of affecting the health of the measurer depending on the type of gas to be measured.

  Therefore, in the conventional apparatus for measuring the amount of generated gas for calibration, it is necessary to solve the problem that the weight of the calibration gas generating tube can be continuously and easily measured without taking out from the thermostat. Have.

  As a specific means for solving the problems of the conventional example described above, the calibration gas generation amount measuring apparatus according to the present invention continuously generates calibration gas by maintaining the calibration gas generation tube at a constant temperature. An apparatus for measuring the amount of the calibration gas generated, comprising: a holder in which the calibration gas generation tube is disposed in a sealed state; a thermostat in which the holder is disposed; and a weigh scale. The weight meter and the calibration gas generation tube are connected via a connecting member so that the calibration gas generation tube is floated in the holder, and the weight of the calibration gas generation tube is continuously increased. The main feature is to measure and measure the amount of calibration gas generated.

  In the present invention, the calibration gas generation tube is a permeation tube or a diffusion tube; the holder is provided with a holder cap formed of a magnetic material that covers the opening of the holder, and the holder The cap includes an annular permanent magnet, and the permanent magnet is filled with a magnetic fluid to maintain a sealed state as an additional requirement.

  A calibration gas generation amount measuring apparatus according to the present invention continuously generates a calibration gas while maintaining a calibration gas generation tube at a constant temperature, and measures the amount of the generated calibration gas. An apparatus comprising: a holder in which the calibration gas generation tube is disposed in a sealed state; a thermostatic chamber in which the holder is disposed; and a weight scale; the weight scale and the calibration gas generation tube; Are connected via a connecting member so that the calibration gas generation tube is floated in the holder, and the weight of the calibration gas generation tube is continuously measured to measure the amount of calibration gas generated. This makes it possible to continuously and easily measure the weight of the calibration gas generation tube without taking it out of the thermostatic bath. Arise It is also without without affecting the health and the like of the measurer, an excellent effect that it is possible to improve the workability.

Next, the present invention will be described in detail based on specific embodiments.
A calibration gas generation amount measuring apparatus according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view of a calibration gas generation amount measuring apparatus. A constant-temperature bath 2 is disposed in the calibration gas generation amount measuring apparatus 1. As the thermostat 2, for example, a device capable of maintaining a constant temperature state such as a permeator (standard gas generator) can be used, and the temperature controller 2 a provided in the thermostat 2 is operated. By doing so, the temperature in the thermostat 2 can be controlled, and the temperature can be adjusted and maintained.

  A substantially cylindrical holder 3 is disposed in the thermostat 2, and the holder 3 is maintained at a temperature set in the thermostat 2. The holder 3 is arranged with the upper side protruding from the upper part of the thermostatic chamber 2, and a holder cap 5 is arranged in the opening 4 formed in the upper part of the holder 3. 5, the opening 4 is covered in a sealed state.

  FIG. 2 shows an enlarged cross-sectional view of only the main part of the opening 4 and the holder cap 5 of the holder 3. The cap body 6 of the holder cap 5 is formed of a magnetic material such as iron or nickel, for example. The cap body 6 is formed with a substantially disc-shaped flat surface portion 7 that contacts the upper surface of the opening 4 of the holder 3 and a hanging portion 8 that covers the outer peripheral surface of the opening 4. The opening 4 can be sealed by the portion 7 and the hanging portion 8. Further, a hole 10 having a diameter larger than that of the peripheral surface of the connecting member 9 is formed at a substantially central portion of the flat portion 7.

  A circular concave portion 11 is formed on the upper side of the flat portion 7. An annular permanent magnet 12 is disposed in the recess 11, and the hole 10 is formed inside the permanent magnet 12, that is, inside the inner diameter of the annular permanent magnet 12. And non-magnetic bodies 14a and 14b in which holes 13 having substantially the same diameter are formed.

  The hole portion 10 of the flat surface portion 7 of the cap body 6 and the hole portion 13 of the nonmagnetic bodies 14a and 14b are in communication with each other, and the connecting member 9 includes the hole portion 10 and the hole portion 13. It is inserted in a movable state.

  A magnetic fluid 15 is filled in the holes 13 formed in the nonmagnetic materials 14 a and 14 b, that is, in the gaps between the nonmagnetic materials 14 a and 14 b and the connecting member 9. The magnetic fluid 15 is composed of, for example, components of ferromagnetic ultrafine particles such as magnetite or composite ferrite, a surfactant, and a base liquid such as water or oil. In order to prevent the particles from aggregating with the surfactant, the ferromagnetic ultrafine particles are stably dispersed in the base liquid.

  For this reason, the magnetic fluid 15 has both the property of a magnetic substance called ferromagnetism and the property of a liquid called fluidity. When the magnetic fluid 15 is disposed in a state where magnetic force exists, Therefore, the magnetic field lines formed by the permanent magnet 12 and the cap body 6 formed by the magnetic body adjacent to the permanent magnet 12 via the non-magnetic bodies 14a and 14b exist in the magnetic flux existing in the magnetic flux. By filling and arranging the magnetic fluid 15, the magnetic fluid 15 acts as a fluid magnetic body and stays in the gap between the non-magnetic bodies 14 a and 14 b and the connecting member 9, so that the magnetic fluid It acts as a magnetic seal based on 15 base liquids (such as oil).

  In this way, the opening 4 of the holder 3 is covered with the holder cap 5 formed of a magnetic material, and the annular permanent magnet 12 and the inner diameter of the permanent magnet 12 are disposed on the holder cap 5. Nonmagnetic bodies 14a and 14b are disposed, and the magnetic fluid 15 is connected to the nonmagnetic bodies 14a and 14b by filling the holes 13 formed in the nonmagnetic bodies 14a and 14b with the magnetic fluid 15. By staying and maintaining in the gap with the member 9, the two environments inside and outside the holder 3 can be isolated and separated, and the inside of the holder 3 can be maintained in a sealed state.

  The nonmagnetic bodies 14a and 14b are not necessarily arranged. For example, the cap body 6 is formed of a magnetic body so as to cover the periphery of the annular permanent magnet 12, and the permanent body of the cap body 6 is formed. A hole may be formed at a position located inside the inner diameter of the magnet 12, and the inside of the holder 3 may be sealed by filling the hole, that is, the inner diameter of the permanent magnet 12 with a magnetic fluid 15. Further, a magnetic material may be provided in place of the non-magnetic material 14a, that is, a magnetic material may be provided at the position 14a above the non-magnetic material 14b.

  A calibration gas generating tube 16 is disposed and accommodated inside the sealed holder 3. As the calibration gas generating tube 16, for example, a calibration gas generating tube such as a permeation tube (P-tube) or a diffusion tube (D-tube) can be used.

  This permeation tube is, for example, a high-quality liquefied gas sealed in a constant quality fluororesin tube. By maintaining the permeation tube at a constant temperature, that is, at a constant temperature, the liquefaction inside the permeation tube Since the gas has the property of permeating and diffusing the tube wall in a short time and the amount of permeating and diffusing is constant, for example, the permeation tube is kept at a constant temperature, and a certain amount of air, nitrogen By blowing dilution gas through the permeation tube, the evaporation and diffusion of various liquids stored in the permeation tube is performed in a constant amount, and the calibration gas with a constant and trace concentration, that is, the concentration of various gases is measured. A calibration gas (standard gas) used as a comparison for the calibration can be obtained continuously, and the amount of the calibration gas generated or Those which can be based on calculating the permeability rate.

  By using this permeation tube, for example, acetaldehyde, ammonia, ethyl mercaptan, ethylene oxide, vinylidene chloride, vinyl chloride, methyl chloride, chlorine, dichloromethane, dimethylamine, methyl bromide, bromine, trimethylamine, sulfur dioxide, nitrogen dioxide , Dimethyl disulfide, hydrogen fluoride, propane, propylene oxide, chlorofluorocarbon 11, methylamine, methyl mercaptan, dimethyl sulfide or hydrogen sulfide can be used for calibration gas (standard gas). It can also be prepared.

  Further, the diffusion tube has substantially the same configuration as the permeation tube, and when the diffusion tube is used, for example, acetone, ethanol, O-xylene, ethyl acetate, toluene, carbon disulfide, benzene, methanol, A calibration gas having a constant or trace concentration such as ethyl bromide, methyl acetate or methyl ethyl ketone can be obtained, and the generation amount or diffusion rate of the calibration gas can be calculated.

  The connecting member 9 made of, for example, a wire is connected to the upper end of the calibration gas generating tube 16, and the other end of the connecting member 9 is disposed above the calibration gas generating tube 16. The calibration gas generating tube 16 is connected to the weighing scale 17 and floats in the space in the holder 3. As the weighing scale 17, for example, an apparatus capable of measuring the weight such as a balance can be used.

  That is, the weighing scale 17 and the calibration gas generating tube 16 are connected via the connecting member 9, and the holder 3 has two environments inside and outside of the holder 3 by the holder cap 5 that is covered in a sealed state. Since the calibration gas generating tube 16 is floated in the space in the holder 3 because it is isolated and separated, the calibration gas generating tube 16 is maintained at a constant temperature by the thermostat 2 and calibrated. Even if the calibration gas generation tube 16 is not continuously removed from the holder 3 disposed in the thermostat 2 after the gas for generation is continuously generated, the weight of the calibration gas generation tube 16 can be measured by a weighing scale. 17, the amount of gas for calibration, the permeation rate, the diffusion rate, etc. can be calculated and measured continuously and easily by changing the weight of the calibration gas generating tube 16. In this case, the measurement gas generation tube 16 does not need to be taken out of the thermostatic chamber 2 without requiring labor and time for the measurement, so that the measurement can be performed in a stable state without causing an error. The workability can be improved without affecting the health of the measurer.

  Furthermore, since the hole 10 of the flat surface portion 7 of the cap body 6 and the hole 13 of the non-magnetic bodies 14a and 14b are not in contact with the connecting member 9, these holes 10 and 13 The connecting member 9 has no resistance due to friction or the like, and the magnetic fluid 15 in contact with the connecting member 9 is in the form of oil or the like, and therefore has a very low frictional resistance. The accuracy of measuring the weight of 16 with the weigh scale 17 can be increased, and the magnetic fluid 15 is less likely to wear, so that the sealed state can be maintained for a long period of time.

  As shown in FIG. 1, the thermostatic chamber 2 may be placed on a balance table 18, and a vibration isolation table 19 is provided on the balance table 18, so that vibration from the outside is applied to the thermostatic chamber. 2 is preferably not transmitted.

  A flow rate adjusting means 20 that continuously feeds a certain amount of dilution gas such as air or nitrogen is connected to the holder 3 disposed in the thermostat 2, and the calibration is disposed and stored in the holder 3. The dilution gas may be continuously blown to the gas generation tube 16.

1 is a cross-sectional view schematically showing a calibration gas generation amount measuring apparatus according to the present invention. It is sectional drawing which expanded and showed only the principal part of the opening part and holder cap of the holder of the generation amount measuring apparatus of the same calibration gas.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Calibration gas generation amount measuring device 2 Constant temperature bath 2a Temperature controller 3 Holder 4 Opening part 5 Holder cap 6 Cap main body 7 Flat part 8 Hanging part 9 Connecting member 10, 13 Hole part 11 Recessed part 12 Permanent magnet 14a, 14b Magnetic body 15 Magnetic fluid 16 Gas generating tube 17 for calibration 17 Weigh scale 18 Balance table 19 Vibration isolation table 20 Flow rate adjusting means

Claims (3)

A device for continuously generating a calibration gas by maintaining the calibration gas generation tube at a constant temperature, and measuring the amount of the generated calibration gas,
A holder in which the calibration gas generating tube is disposed in a sealed state;
A thermostatic chamber in which the holder is disposed;
Consisting of a weigh scale,
The weighing scale and the calibration gas generation tube are connected via a connecting member to float the calibration gas generation tube in the holder,
A calibration gas generation amount measuring device characterized by continuously measuring the weight of the calibration gas generation tube to measure the calibration gas generation amount. The calibration gas generating tube is:
2. The calibration gas generation amount measuring device according to claim 1, wherein the calibration gas generation amount measuring device is a permeation tube or a diffusion tube. The holder is provided with a holder cap formed of a magnetic material that covers the opening of the holder,
An annular permanent magnet is disposed on the holder cap,
2. The calibration gas generation amount measuring apparatus according to claim 1, wherein the permanent magnet is filled with a magnetic fluid to maintain a sealed state.

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