I -C35, to as high as 50 or higher. Oil and Water do not mix, the oil either flows on top or is emulsified. As far as the EPA is concerned, according to EPA Method 1664, oil and grease is that material extracted from produced water at a pH of 2 and remaining after the solvent is evaporated. Of course, there are many other oils aside from crude oils, such as mineral oils, vegetable oils, animal fats and essential oils. Those are found less frequently in standard industrial waste waters.
Oil rises rapidly to the surface under quiescent conditions.
The droplet size is 150 micron. This oil is present as a sheen, and can be removed with an oil skimmer or by an over- flow weir, down to I 00 ppm. The remaining oil is removed with granular organoclay placed into a activated carbon adsorber. These oil droplets range in size from 20-150 microns. Mechanically emulsified oil floats around within the water, and is stabilized by electrical charges and other forces.