What is an agar probe?

Agar probes are use in applications where there is an oil/water interface that needs to be monitored. Often in such interfaces an emulsion occurs (a mixture of oil and water droplets). Such emulsions make it difficult to determine between the emulsion and the pure water/ pure oil strata, using standard methods such as a float level. Agar probes emit microwaves, which are readily absorbed by water but not by oil. By measuring the level of microwave energy absorbed by the surrounding fluid the agar probe can be use to determine whether it is in a water, oil or emulsion strata. A typical application would be in the oil and gas production. The purpose here is to separate and remove pure water used in processing from waste oil. Since this water can be recycled for reuse in processing or even pumped back into the environment, it is important that only pure water and not oil or an oil/water emulsion is pumped from the seperator tanks. Agar probes are a reliable way of ensuring this.