Electrochemical sensors for gas pipelines using ion conducting membranes

Electrochemical sensors can be used for a wide range of online in-situ process monitoring applications. However, the lack of a consistent electrolyte layer has limited electrochemical monitoring in gas and supercritical fluid streams. A solid state sensor is being designed that uses an ion conducting membrane to perform conductivity and corrosion measurements in natural gas pipelines up to 1000 psi. Initial results show that membrane conductivity measurements can be correlated directly to water content down to dew points of 1 °C with good linearity. Corrosion monitoring can also be performed using methods such as linear polarization resistance and electrochemical impedance spectroscopy (EIS), though care must be taken in the electrode design to minimize deviation between sensors.