Hydrocarbon Gas Measurements Using Nuclear Magnetic Resonance

A method of using a transient NMR response signal to determine physical properties of gases, specifically calorific content and compressibility, while the gas is in-line. The amplitude of the free induction decay signal, as well as relaxation time constants, are used to identify components of a gas mixture and to determine relative composition. This data is then used to calculate calorific value and compressibility as a function of the hydrogen content of components of the gas rather than as a function of the total hydrogen content of the gas.