Quality control of GC makeup gas flow
AssigneeSchlumberger Technology Corporation
InventorsElena Borisova, Pierre Beaudy, Jean Pierre Bailly
Life of this patent
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Abstract
A method for quality control checking a gas chromatography apparatus at a rig site, the GC apparatus including at least a main column and a makeup flow line in fluid communication with a detector manifold. The GC apparatus measures a first chromatogram of a gas sample with a first makeup gas flow rate and a second chromatogram of the gas sample with a second makeup gas flow rate, wherein the second makeup gas flow rate is greater than the first makeup gas flow rate. The elution times of at least one common peak in the first and second chromatograms are compared to indicate a leak or an obstruction in the makeup flow line or the detector manifold.
Claims20
A method for quality control checking a gas chromatography (GC) apparatus, the method comprising:
- providing a GC apparatus and a gas sample, the GC apparatus including at least a main column and a makeup gas flow line in fluid communication with a detector manifold, the main column configured to separate light hydrocarbon compounds in a gas stream;
- using the GC apparatus to measure a first chromatogram of the gas sample with a first makeup gas flow rate;
- using the GC apparatus to measure a second chromatogram of the gas sample with a second makeup gas flow rate, wherein the second makeup gas flow rate is greater than the first makeup gas flow rate;
- and
- comparing elution times of at least one common peak in the first chromatogram and the second chromatogram to indicate a leak or an obstruction in the makeup gas flow line or the detector manifold.
A gas chromatography (GC) apparatus comprising:
- a sample collection loop, a main column, and a carrier gas inlet in fluid communication with a multiport valve, the main column configured to separate light hydrocarbon gases in a gas stream;
- a detector manifold in fluid communication with the main column and a makeup gas flow line;
- a GC detector in fluid communication with the detector manifold;
- and
- an electronic controller configured to
- cause the GC apparatus to measure a first chromatogram of a gas sample with a first makeup gas flow rate;
- cause the GC apparatus to measure a second chromatogram of the gas sample with a second makeup gas flow rate, wherein the second makeup gas flow rate is greater than the first makeup gas flow rate;
- and
- compare elution times of at least one common peak in the first chromatogram and the second chromatogram to indicate a leak or an obstruction in the makeup gas flow line or the detector manifold.
A method for quality control checking a gas chromatography (GC) apparatus, the method comprising:
- providing a GC apparatus and a gas sample including a plurality of light hydrocarbon gases, the GC apparatus including at least a main column and a makeup gas flow line in fluid communication with a detector manifold, the main column configured to separate light hydrocarbon compounds in a gas stream;
- using the GC apparatus to measure a first chromatogram of the gas sample with no makeup gas;
- using the GC apparatus to measure a second chromatogram of the gas sample with a nonzero makeup gas flow rate;
- and
- comparing elution times of a plurality of common peaks in the first chromatogram and the second chromatogram to indicate a leak or an obstruction in the makeup gas flow line or the detector manifold.
Dependencies are inferred from the claim text.