Separation tanks are widely used in the oil and gas industries where pressurized tanks separate fluids into oil, gas and water. Separators operate on the principle of density and the stratification of the three components: gas on top, oil in the middle and water on the bottom.
When mixed with water, oil appears in the form of droplets which rise to the surface. Smaller droplets may be held down by molecular or electrostatic forces. To overcome this problem, separation tanks utilize filters or diffusers. Both methods increase coalescence, improving the separation rate. Diffusers further reduce turbulence in the separation tank.
Once separation occurs, weirs prevent the oil from escaping with the water. Separation is optimized by a motorized wheel skimmer that prevents the growth of anaerobic bacteria.