Measurement of Helium Micro Flowrates with High Accuracy for Gas Chromatography |
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| J. Barbe, F. Dijoux, C. Yardin, T. Macé |
- Abstract:
- More and more chemical analysis laboratories using gas chromatographs need to measure the different flowrates involved during the analysis process (split ratio, column flow). The measurement of the column flow is certainly the most difficult because the flowrate of carrier gas is generally very small. For example, the flowrate of helium which is the most often used carrier gas is typically less than 15 µg/s (5 cm³/min). To calibrate helium flowmeters, the "traced gas method" developed at LNE for nitrogen has been optimized for helium microflow measurements in the range of 0.75 µg/s to 30 µg/s. The traced gas method, the uncertainty estimation of the calibration bench and the calibration results of a laminar flow element type Molbloc and an industrial mass flowmeter are presented in this paper.
- Keywords:
- micro flowrate, gas chromatography, Molbloc™
- Download:
- IMEKO-TC9-2010-070.pdf
- DOI:
- -