Patent ID: 11874230
Assignee: ENDRESS+HAUSER OPTICAL ANALYSIS, INC.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method for determining an amount of a Raman-invisible gas in a sample gas stream, the method comprising:
providing a Raman spectroscopic device, including a Raman laser;
performing a Raman analysis of a calibration gas stream, wherein the Raman analysis of the calibration gas stream includes measuring a pressure and a temperature of the calibration gas stream;
determining a first set of absolute Raman bands from the Raman analysis of the calibration gas stream, wherein the first set of absolute Raman bands correlate to Raman-visible gases within the calibration gas stream;
calculating, using the first set of absolute Raman bands, first amounts of each Raman-visible gas present in the calibration gas stream;
waiting a first time period;
performing a Raman analysis of the sample gas stream, wherein the Raman analysis of the sample gas stream includes measuring a pressure and a temperature of the sample gas stream;
determining a second set of absolute Raman bands from the Raman analysis of the sample gas stream, wherein the second set of absolute Raman bands correlate to the Raman-visible gases within the sample gas stream;
calculating, using the second set of absolute Raman bands, second amounts of each Raman-visible gas present in the sample gas stream;
comparing the amount of each Raman-visible gas in the sample gas stream to the respective amount of each Raman-visible gas in the calibration gas stream;
attributing decreases in the amounts of the Raman-visible gases in the sample gas stream to a displacement of the Raman-visible gases in the sample gas stream by the Raman-invisible gas in the sample gas stream; and
calculating the amount of the Raman-invisible gas in the sample gas stream using the decreases in the amounts of the Raman-visible gases in the sample gas stream.