| 摘要 |
<p>An electrical sensor module (10) for monitoring chemical properties of oil well fluids comprises at least one electrochemical sensor (18b, c, d) for a chemical species, for example to detect pH and chloride ion concentration. A micro-porous barrier (26) separates the electrochemical sensors from the environment of the module, the micro-porous barrier being of a material which is readily wetted by water. Periodic application of a current pulse between the barrier (26) and a counter electrode (27) enables fouling material to be removed from the micro-porous barrier.</p> |
