Devices and methods for quantification of liquids in gas-condensate wells

An apparatus for determining a flow rate of a wet-gas flow or a component of said wet-gas flow, including:

• a first light source and a second light source located downstream of said first light source;
• and
• two or more sensors for detecting the transmittance or scattering of the light from the first and second light sources through said wet-gas flow;
• and
• cross-correlator for determining said flow rate by cross-correlating the detected transmittance or scattering of light from said first and second light sources.

An apparatus for measuring the fractions of water and condensate in a multi-phase gas flow, the apparatus comprising:

• a water measuring device comprising
• one or more light sources emitting at a first wavelength at which water is highly absorbing and emitting at a second wavelength close to the first wavelength and at which water is not highly absorbing;
• and
• one or more sensors for detecting the transmittance of the light at the first and second wavelengths through said gas flow;
• and
• a condensate measuring device comprising
• one or more light sources emitting at a third wavelength at which condensate is highly absorbing and emitting at a fourth wavelength close to the third wavelength and at which the condensate is not highly absorbing;
• and
• one or more sensors for detecting the transmittance of the light at the third and fourth wavelengths through said gas flow;
• the apparatus further including processing means for determining liquid fractions of water and condensate in the wet gas flow by correcting the transmittance measured at the first wavelength for the effects of scattering using the transmittance measured at the second wavelength and correcting the transmittance measured at the third wavelength for the effects of scattering using the transmittance measured at the fourth wavelength.

A device for measuring the fraction of a liquid in a wet gas flow, the device including:

• one or more light sources emitting at a first wavelength at which the liquid is highly absorbing and emitting at a second wavelength close to the first wavelength and at which the liquid is not highly absorbing;
• and
• one or more sensors for detecting the transmittance of the light at the first and second wavelengths through said gas flow,
• at least one additional sensor arranged at an angle to the transmission path of at least one of said light sources to detect scattered light;
• the device including processing means for determining a liquid fraction of the liquid in the wet gas flow by correcting the transmittance measured at the first wavelength for the effects of scattering using the transmittance measured at the second wavelength and also including processing means for measuring the cross-correlation between the levels of light detected at the sensors for detecting transmittance and the additional sensor and determining a flow rate of the wet-gas flow or a component of the wet-gas flow from said measured cross-correlation.