Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
  • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
  • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
  • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
  • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
  • G01N21/3554—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for determining moisture content
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
  • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
  • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
  • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
  • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
  • G01N21/3504—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing gases, e.g. multi-gas analysis
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/0004—Gaseous mixtures, e.g. polluted air
  • G01N33/0006—Calibrating gas analysers
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N2201/00—Features of devices classified in G01N21/00
  • G01N2201/06—Illumination; Optics
  • G01N2201/061—Sources
  • G01N2201/06113—Coherent sources; lasers
  • G01N2201/0612—Laser diodes

Definitions

• the present invention relates to an instrument for the measurement of isotopes in a sample gas.
• laser diode spectrometers can be used recently, exploiting the absorption in the near infrared of water molecules.
• One of the advantages of these instruments, especially because of their small footprint, is that they are deployable outside a dedicated analysis laboratory, and operate continuously.
• Calibration consists in introducing, one after the other, two reference liquid samples constituted by waters whose absolute isotopic values are perfectly determined, chosen in such a way that they are not too far apart from each other , while framing the values of the samples to be analyzed. The values then measured by the instrument make it possible to determine a calibration straight line of the instrument and thus to be able to transform the values measured thereafter into absolute values.
• the instrument is equipped with a vaporizer that transforms the waters of the reference samples into a vapor phase and measures them as any air sample.
• SDM Sensor Data Module
• SDM "and consists of two syringes connected on the one hand each to a bulb containing the corresponding reference sample and, secondly, via an injection head, the vaporizer, itself connected to the analyzer.
• one of the syringes sucks through the tubings an amount corresponding to a predefined volume (for example 250 microliters), and distributes it very slowly to the analyzer via the vaporizer, and the analyzer measures during all this duration (which lasts for example of the order of 30 minutes) this reference sample. This step is then renewed with the other syringe.
• a predefined volume for example 250 microliters
• the tubings used are typically 1/16 "outside diameter and their internal diameter does not exceed 0.20 mm, and the system does not remain under pressure. continuously during the period of non-use, which inevitably leads to the appearance of air microbubbles in the tubes.
• the invention aims to provide an instrument for performing a purge of tubing for calibration, without human intervention and remote.
• the invention aims to provide an instrument for measuring the concentration of isotopes of water in a sample gas charged with water vapor, comprising:
• At least one inlet manifold for receiving a purge liquid or a calibration liquid
• an analyzer comprising:
• connection circuit in normal measurement operation connecting the input to the output via said analysis means
• a vaporizer comprising:
• At least one input connected to said input tubing; means for vaporizing said purge liquid or said calibration liquid;
• connection circuit with the analyzer for transmitting said vaporized calibration liquid to the analyzer, said connection circuit with the analyzer connecting the vaporizer inlet to the analyzer output via said analysis means;
• an output circuit for discharging the overflow of said vaporized calibration liquid during measurement by the analyzer, said output circuit being arranged so that the overflow is discharged without passing through the analyzer;
• a purge circuit connected to the inlet of the vaporizer for sucking said vaporized purge fluid through the vaporizer during a purge operation, said purge circuit being arranged such that said vaporized purge fluid does not pass through the vaporizer; analyzer;
• a purge state of the tubing (provided that the instrument generally comprises two pipes for which this purge can be carried out successively) can be performed automatically without altering the accuracy of the analyzer measurements. It is no longer necessary to disconnect the tubings leading the reference samples, as is known in the prior art.
• the analyzer is bypassed so that the purge liquid does not pass through the analyzer when it is used to purge the tubing. In other words, the flow evacuated from the vaporizer is deviated without this flow passing through the analyzer.
• the purge liquid is not likely to damage by immersion the means of analysis (typically an infrared absorption spectrometer) included in the analyzer.
• This rapid and automatic purge also makes it possible to avoid water saturation during the following measurements and to rapidly dry the fluid circuit without interrupting the use of the analyzer for too long a period; to purge, the purge liquids are sent via the inlet manifolds into the vaporizer, where they are vaporized, and are discharged through the purge circuit.
• the quantity of liquid thus evacuated is chosen so as to replace the volume of liquid initially present in the tubes, potentially charged with air bubbles, with liquid free of air bubbles, coming from the reservoir containing the reference sample and taken at the time of the purge operation.
• the output circuit of the open vaporizer (for example in the open air) is also kept so as to evacuate the overflow of liquid present in the vaporizer and which could be introduced into the analyzer.
• the instrument according to the invention may also have one or more of the following characteristics, considered individually or in any technically possible combination:
• said selective establishment means comprise a first valve in the output circuit of the vaporizer and a second valve in the purge circuit, the first valve being open in the first state and closed in the second state, the second valve being open in the second state; the second state and closed in the first state;
• valves are solenoid valves controlled by a control circuit
• the purge circuit comprises a pump
• the purge circuit comprises a desiccator upstream of the pump
• the second valve is arranged upstream of the pump
• the instrument according to the invention comprises two inlet pipes, each being adapted to receive a purge liquid or a calibration liquid, said vaporizer comprising two inlets connected respectively to one of said inlet pipes;
• the instrument according to the invention comprises software means for remote or automatic control of said means for selectively establishing said first and second states.
• FIG. 1 to 3 show a measuring instrument according to the invention according to three operating states in normal operating mode, calibration mode and purge mode;
• FIG. 4 represents an exemplary control circuit of the instrument of FIG. 1.
• the measuring instrument 10 according to the invention shown in FIGS. 1 to 3 comprises:
• a vaporizer 13 capable of receiving two calibration liquids via two inputs E1 and E2 respectively connected to two Tub1 and Tub2 tubings;
• the measuring instrument 10 uses the system for calibration called "Standard Delivery Module (S.D.M.)" and comprises two syringes 34 and 35 each connected to a bulb (not shown) containing a reference sample; these syringes 34 and 35 are advantageously motorized to be remotely controlled and are respectively connected Tub1 and Tub2 tubing.
• S.D.M. Standard Delivery Module
• the analyzer includes analysis means 14 formed for example by an infrared absorption spectrometer using laser diodes.
• the analyzer is for example an analyzer bearing the commercial reference PICARRO LTub130-i.
• the vaporizer 13 makes it possible to transform the waters of the reference samples in the vapor phase received on one of its inputs E1 or E2 via one of the Tub1 or Tub2 tubings and to measure them as any air sample.
• the vaporizer 13 according to the invention furthermore comprises:
• the input E1 (and the input E2) of the vaporizer communicates with the connection circuit C2, the output circuit C3 and the purge circuit C4.
• the output circuit C3 comprises a valve 31, normally open whose outlet is in the open air.
• the purge circuit C4 comprises a desiccator 42, a normally closed valve 44 and a pump 45 whose outlet is in the open air.
• the dryer 42 arranged upstream of the pump 45 makes it possible not to deteriorate it by saturation with water, and comprises, for example, a desiccant cartridge, for example of the type 8 wicks with colored indicator, for example W.H.HAMMOND DRIERITE COMPANY.
• the pump 45 is preferably a diaphragm-type pump such as the pump sold under the reference KNF N86KN.18.
• the valves 31 and 44 are for example 2-way solenoid valves
• valves 31 and 44 are for example solenoid valves controlled by a control circuit 50, shown schematically in FIG. 4 and which can be integrated into the instrument 10 according to the invention.
• This control circuit 50 comprises software means for controlling said valves 31 and 44.
• FIG. 2 represents the state S1 of operation of the instrument 10 according to the invention in calibration mode (denoted by the term calibration).
• a calibration liquid is injected through the tubing Tub1, enters the vaporizer 13 via the inlet E1 and is vaporized by the vaporizer 13.
• the vaporized liquid then follows the circuit C2 which allows it to pass from the vaporizer 13 to the analyzer 12 and to be analyzed by the analysis means 14 to be evacuated by the output 01.
• the valve 31 being open, the overflow of vaporized liquid which does not enter the analyzer 12 is discharged via the outlet circuit C3 in the open air.
• the instrument 10 comprises for example a valve 33 for isolating the input 11 of the analysis means 14.
• FIG. 3 represents the operating state S2 of the instrument 10 according to the invention in the purge mode.
• the valve 31 is closed and the valve 44 is opened and the pump 45 is put into operation.
• One of the reference liquids (which is serve as purge liquid) from the Tub1 tubing in the vaporizer 13 and the gas produced by the vaporization of this liquid is sucked by the pump 45.
• This purge action is then repeated with the other reference liquid injected via the tubing Tub2.
• the instrument 10 according to the invention comprises For example, a valve 32 between the vaporizer and the analysis means 14. The connection circuit C2 of the vaporizer with the analyzer is thus interrupted.
• valves 32 and 33 can advantageously be replaced by a three-way valve (i.e. a valve allowing via a connection at "Y" to connect the output 01 of the analyzer respectively to the circuit C1 or the circuit C2).
• the quantity of liquid, sufficient to evacuate the bubbles present in Tub1 or Tub2 tubing, is advantageously the total volume of the syringes.
• the calibration line is calculated, and it is then possible to measure the isotopes of the water vapor contained in the sample gas.
• the analyzer 12 executes sequentially and automatically, for example using software, all the steps necessary to purge before a new calibration.
• the instrument 10 can also be arranged to allow remote maintenance intervention, for example using free software available as Teamviewer or Log me in. This allows the user to regain control of the actions during routine automatic measurements. He can then trigger the start-up of the system by using a feature of the analyzer software for controlling the analyzer valves, this software being for example the one known as External Valve Sequencer of the company PICARRO.
• the control circuit 50 is for example connected to an output channel of the analyzer for sending to the control circuit 50 an order of tilting of the valves 31, 32, 33 and 44, and starting of the extraction pump 45, which is performed simultaneously with the closing of the valve 31 of the output circuit C3 and the opening of the valve 42 of the purge circuit C4 or operation of the motorized syringes 34 or 35.
• the purge can be carried out automatically and quickly, as often as necessary.
• valves 31 and 44 can be replaced by a three-way valve (i.e. a valve allowing via a "Y" connection to connect the Tub1 or Tub2 tubing respectively to the circuit C3 or the circuit C4). If necessary, the valve 44 is absent, and the stoppage of the pump 45 is sufficient to prevent a flow of fluid through the purge circuit to the extent that the pump is sealed.

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• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Analytical Chemistry (AREA)
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• General Health & Medical Sciences (AREA)
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• Food Science & Technology (AREA)
• Combustion & Propulsion (AREA)
• Sampling And Sample Adjustment (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)

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• 2013
  • 2013-02-12 FR FR1351175A patent/FR3002042B1/fr not_active Expired - Fee Related
• 2014
  • 2014-02-10 FR FR1451019A patent/FR3002043B1/fr not_active Expired - Fee Related
  • 2014-02-11 WO PCT/EP2014/052637 patent/WO2014124934A1/fr active Application Filing
  • 2014-02-11 EP EP14706793.8A patent/EP2956769A1/de not_active Withdrawn
  • 2014-02-11 CN CN201480008301.7A patent/CN105209904B/zh not_active Expired - Fee Related
  • 2014-02-11 US US14/408,858 patent/US9625375B2/en not_active Expired - Fee Related

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