US 10,545,089 B2 · Gas detection apparatus and method

Abstract

A method of identifying the presence of a first gas such as methane within a sample, for example containing natural gas. A detector is provided having a sensor responsive to a first wavelength, a sensor responsive to a second wavelength, and a sensor for collecting reference readings. A gas sample is analysed to obtain a first absorption reading corresponding to the first wavelength, a second absorption reading corresponding to the second wavelength and a reference reading. A first absorption figure is calculated using the first absorption reading and the reference reading, and a second absorption figure using the second absorption reading and the reference reading. The sensor for each wavelength is calibrated for detecting the first gas such that the data collected at each wavelength gives the same reading when only said first gas is present in a sample.

Claims30

Dependent claims

A method of measuring the concentration of a first gas in a sample, comprising the steps of providing a detector having a sensor responsive to a first wavelength, a sensor responsive to a second wavelength, and a sensor for taking reference readings;

applying a lineariser function to each of the first and second absorption figures to calculate first and second concentration figures, calibrating the sensor for each wavelength for detecting the first gas such that the data at each wavelength gives the same reading when only said first gas is present in a sample;
analysing a gas sample to obtain a first absorption reading at the first wavelength, a second absorption reading at the second wavelength and a reference reading;
calculating a first concentration figure (c1) and a second concentration figure (c2) using the reading at the first wavelength, the reading at the second wavelength and the reference reading, and calculating a corrected concentration figure (ccor) indicative of the actual concentration of said first gas in the sample using the equation ccor=c1−X·(c2−c1), in which X=D·A·(c1/c2)B, where A and B are constants for a particular pair of filter wavelengths chosen depending on the gases which are being looked for in the sample, and D is a correction factor which depends on concentration of the first gas in the sample.

applying a lineariser function to each of the first and second absorption figures to calculate first and second concentration figures, calibrating the sensor for each wavelength for detecting the first gas such that the data at each wavelength gives the same reading when only said first gas is present in a sample;
analysing a gas sample to obtain a first absorption reading at the first wavelength, a second absorption reading at the second wavelength and a reference reading;
calculating a first concentration figure (c1) and a second concentration figure (c2) using the reading at the first wavelength, the reading at the second wavelength and the reference reading, and calculating a corrected concentration figure (ccor) indicative of the actual concentration of said first gas in the sample using the equation ccor=c1−X·(c2−c1), in which X=A·(c1/c2)B, where A and B are constants for a particular pair of filter wavelengths chosen depending on the gases which are being looked for in the sample.

A method of identifying the presence of a first gas within a sample, comprising the steps of providing a detector having a sensor responsive to a first wavelength, a sensor responsive to a second wavelength, and a sensor for collecting reference readings;

analysing a gas sample to obtain a first absorption reading corresponding to the first wavelength, a second absorption reading corresponding to the second wavelength and a reference reading;
calculating a first absorption figure using the first absorption reading and the reference reading, and a second absorption figure using the second absorption reading and the reference reading;
applying a lineariser function to each of the first and second absorption figures to calculate first and second concentration figures;
calibrating the sensor for each wavelength for detecting the first gas such that the data collected at each wavelength gives the same reading when only said first gas is present in a sample;
calculating the ratio of the first concentration figure to the second concentration figure, and using said ratio to identify whether only the first gas is present in the sample.

2 more elements

Dependencies are inferred from the claim text.

Gas detection apparatus and method

Life of this patent

Gas detection apparatus and method

Life of this patent

Abstract

Claims30