Determining calorific value of natural gas by infrared absorption spectrometry comprises use of single temperature-dependent-variable spectral monomode laser

摘要

Determining the calorific value of natural gas by IR absorption spectrometry uses a single temperature-dependent-variable spectral monomode laser. The number of natural gas components to be detected is stipulated according to a specified accuracy. The emission wavelength of the laser covers at least one specified absorption line in the spectrum of each component. Preferred Features: The monomode laser is a laser diode. The process is carried out in the near or middle IR wavelength region. CH-vibrations of the hydrocarbon molecule are measured in the region of 1.68 Microm in the upper band region. At least methane, ethane, propane and butane are measured. Heavy hydrocarbons, water and carbon dioxide are measured by a further laser or laser diodes. The pressure of the natural gas corresponds approximately to atmospheric pressure or below. -