04492862 is referenced by 59 patents and cites 22 patents.

Beams (11) and (13) produced by helium-neon gas lasers (10) and (12) are directed at photoacoustic absorption cells (20) and (21) containing a flowing sample gas stream recovered from coal, oil and natural gas well drilling. The common hydrocarbon gases and vapors within cell (20) highly absorb the infrared energy emitted by laser (10) thereby producing an acoustic disturbance which is detected by a transducer (34) which produces an electrical output signal proportional to the concentration of the hydrocarbon gases and vapors. The methane gas within cell (21) weakly absorbs the infrared energy of laser beam (13), and thus the resulting output signal produced by a transducer (35) serves as a reference signal for determining the methane concentration. The output signals from transducers (34) and (35) are used by data processing unit (40) to compute the total concentration of hydrocarbon gases and vapors and the concentration of methane gas within cells (20) and (21). A turnable carbon dioxide gas laser (44) produces laser beams (45) and (47) both in the infrared region which are highly absorbed by the propane and n-butane component gases, respectively, flowing through photoacoustic cell (48). The level of energy absorbed from these two beams, as determined by the energy of the acoustic disturbance produced within cell (48) induces production of an electrical output signal by transducer (56) at levels proportional to the concentrations of the propane and n-butane gases in cell (48). The output signals from transducer (56) are then used by data processing unit (40) to compute the concentrations of propane, n-butane gases and C.sub.5.sup.+ gases in the sample.

Title
Method and apparatus for analyzing components of hydrocarbon gases recovered from oil, natural gas and coal drilling operations
Application Number
6/290824
Publication Number
4492862
Application Date
August 7, 1981
Publication Date
January 8, 1985
Inventor
Stephen E Moody
Kirkland
WA, US
Leonard Y Nelson
Seattle
WA, US
Jack Grynberg
Englewood
CO, US
Agent
Christensen O Connor Johnson & Kindness
Assignee
Mathematical Sciences Northwest
WA, US
IPC
G01V 5/00
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