Apparatus for and method of gas analysis
View Patent ↗A method for preparing a sample for analysis includes separating a gas sample into at least one component sample in a separation unit. The output of the at least one component sample from the separation unit is detected, for example, using a thermal conductivity detector. A hydrocarbon in the component sample is combusted in a combustion unit to generate a combustion product. The at least one component sample is collected in a sample collector and supplied to an analysis unit. In some embodiments, the analysis unit may be used to determine an isotopic ratio of the at least one component sample.
1. A method of preparing a sample for analysis, comprising:
separating a gas sample into at least one component sample in a separation unit;
detecting an output of the at least one component sample from the separation unit;
combusting a hydrocarbon in the at least one component sample in a combustion unit to generate a combustion product;
collecting the combustion product in a sample collector; and
supplying the collected combustion product to an analysis unit.
2. The method of claim 1 ,
wherein the combustion product is at least one of carbon dioxide and carbon monoxide.
3. The method of claim 1 , wherein the combustion unit comprises a gas combustion chamber.
4. The method of claim 3 , wherein the gas combustion chamber includes copper wire and platinum wire within a tubing comprising nickel.
5. The method of claim 1 , wherein the analysis unit is a cavity ring down spectrometer.
6. The method of claim 5 , wherein the cavity ring down spectrometer is operated in a static mode.
7. The method of claim 1 , further comprising:
analyzing the combustion product in the analysis unit to determine an isotopic ratio of the at least one component sample.
8. The method of claim 7 , wherein the isotopic ratio is a carbon isotopic ratio.
9. The method of claim 1 , wherein a thermal conductivity detector is used for detecting the output of the at least one component sample from the separation unit.
10. The method of claim 1 , further comprising:
supplying the gas sample to the separation unit from a continuous gas flow.
11. The method of claim 10 , wherein the continuous gas flow is a mudgas stream from a wellbore.
12. The method of claim 1 , wherein the separation unit is a chromatographic column.
13. The method of claim 1 , further comprising:
removing water from the at least one component sample.
14. The method of claim 1 , further comprising:
supplying air as a carrier gas to the separation unit and the sample collector.
15. A method of analyzing mudgas components, comprising:
supplying a mudgas sample to a gas chromatograph to separate the mudgas sample into different components on the basis of component elution times;
detecting an output of at least one component of the mudgas sample from the gas chromatograph using a thermal conductivity detector;
supplying the at least one component to a combustion chamber and combusting a hydrocarbon in the at least one component to form a combusted component sample including at least one of carbon dioxide and carbon monoxide;
collecting the combusted component sample in a sample collection unit; and
supplying the combusted component sample from the sample collection unit to an analysis unit.
16. The method of claim 15 , further comprising:
converting carbon dioxide or carbon monoxide in the combusted component sample to methane before supplying the combusted component sample to the analysis unit.
17. The method of claim 15 , further comprising:
determining a carbon isotopic ratio in the mudgas sample based on an analysis of the combusted component sample in the analysis unit.