By Jim Fitch
Machinery Lubrication Magazine
Historically, water contaminated oil has been said to exist in two states:
- Dissolved water (bound molecularly in the matrix of the oil)
- Free water (not molecularly bound)
In the last 30 years or so, most of the literature, including Noria’s publications, refer to water as having three states. Free water has been redefined as being water that, by force of gravity, will phase out of the oil. This means it will separate below (most common) or above the oil phase depending on oil density.
The new third state is emulsified water. Water that is held tightly in micro-globules in the oil is no longer referred to as free water. Instead, it has been more accurately referred to as emulsified water, or a “micro-emulsion”.