Method for on-site monitoring of the quality of the gases delivered to an industrial consumer site using the thermal conductivity technique

A method for on-site monitoring of the quality of a gas delivered to a consumer site, the monitoring being carried out after a delivery of the gas to the consumer site, in order to declare the delivered gases compliant or non-compliant with specifications for the gas, the delivered gas being a single gas or a mixture of gases, said method comprising the steps of:

• providing, after delivery of the gas and receipt thereof at the consumer site, a gas identification device that comprises a thermal conductivity analyzer that has been precalibrated using pure calibration gases or a mixture of pure calibration gases and a data acquisition and processing system;
• acquiring one or more samples of the delivered gas using the gas identification device;
• acquiring one or more samples of a reference gas using the gas identification device;
• carrying out one or more measurements of the thermal conductivity of the sample(s) of the reference gas using the gas identification device;
• using the gas identification device to compare the thermal conductivity measurements of the sample(s) of the reference gas with thermal conductivity values of the pure calibration gas or the mixture of pure calibration gases obtained during said precalibration;
• carrying out one or more measurements of the thermal conductivity of the sample(s) of the delivered gas using the gas identification device;
• using the gas identification device to compare the thermal conductivity measurements of the sample(s) of the delivered gas with the thermal conductivity measurements of the sample(s) of the reference gas;
• and
• based upon the comparison, by the gas identification device, of the thermal conductivity measurements of the sample(s) of the delivered gas with the thermal conductivity measurements of the sample(s) of the reference gas, using the gas identification device to:
• declare that the delivered gas is compliant with the specifications for the gas and authorize transfer of the delivered gas to storage vessels or,
• declare that the delivered gas is non-compliant with the specifications for the gas and not authorize transfer of the delivered gas to storage vessels.