Determination of the quality of a gas

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein for each physical quantity to be determined with respect to the quality of the gas, at least one spectral vector {overscore (S)} must be created from values coming from spectral regions with different boundary wavelengths or different sizes of spectral regions or different numbers of spectral regions.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein a separation formulation is carried out for determining the physical quantity, in which one part of the physical quantity to be determined varies with the state and composition of the probe gas and another part is influenced only slightly by the composition and state of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectra vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity comprises a compressibility coefficient K of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined comprises a compressibility factor Z of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined comprises a density ρ of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined comprises a Wobbe index of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined is a methane factor of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined is the molar mass of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined is the density of a carbon dioxide part of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein the physical quantity to be determined is the dew point of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein during said step of multiplying, a correcting function is included, said correcting function taking into account equipment differences between a measurement arrangement during determination of the factor vectors {overscore (V)} with the calibrating gases and a measurement arrangement during determination of the spectral vector {overscore (S)} of the probe gas.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein a boundary wavelength of chosen spectral regions during recording of the transmission spectrum is determined by appointing the boundary wavelength relative to a reference signal.

A procedure for determining quality of a probe gas, comprising:

• determining a transmission spectrum of the probe gas at operating conditions by spectroscopical methods of measurement;
• determining pressure p and temperature T of the probe gas;
• determining at least one spectral vector {overscore (S)} in a number of selected spectral regions by integrating quantities of the transmission spectrum of the probe gas, the spectral vector having as components values of integrals with respect to the selected spectral regions and being characteristic for the properties of the probe gas at operating conditions;
• and
• multiplying said spectral vector {overscore (S)} with a factor vector {overscore (V)}, said factor vector {overscore (V)} determined by calibrating measurements of spectral vectors {overscore (S)} of calibrating gases having known features and under known conditions, in which a respective factor vector {overscore (V)} is used to determine a physical quantity based on the quality of the gas, wherein among spectral regions in which the transmission spectrum of the probe gas contains information about the composition of the probe gas, other spectral regions are surveyed in which very little or no absorption by the gas probe occurs.