January 1, 2010

When to Use an Oil Skimmer

Jim Petrucci

Oil skimmers are very effective in removing oil from wastewater before discharge but are also perhaps the most efficient and economical approach.

Despite these advantages, oil skimmers are not found in every power plant. Some plants rely on less-efficient oil removal procedures, failing to recognize that even a single release could cost more money than upgrading a facility to modern oil-skimming equipment.

An oil skimmer (Figure 8) efficiently removes oil from water continuously and puts it into a collection tank, so it can then be recycled. Continuous removal also eliminates oil build-up, greatly reducing evaporation loss and the likelihood of oil escaping.


8. Skimming oil. Oil in plant sumps and other wastewater containment areas can be economically removed using an oil skimmer. In this design, a polymer hose passes through the sump to collect oil that is continuously skimmed from the surface of the hose and collected as illustrated. Courtesy: Oil Skimmers Inc.

Let’s review your options other than real-time oil skimming for removing oil from wastewater, and you can decide which approach is more attractive to you.

Absorbent Pads, Booms, or Pillows

Absorbent pads are one method a facility can use to remove waste oil. Pads are available in different shapes and sizes and are made from a variety of synthetic materials.

These are useful in an emergency, for removing small amounts of oil or soaking up oil on plant floors. If only a few pads or pillows are used per month, then they are most likely sufficient.

However, the results of using absorbents are not always environmentally sound. Only a small amount of oil can be squeezed out of the pad for recycling. The remaining oil must be disposed of in a landfill or burned. At some point, the cost associated with the purchase, disposal, and deployment of these absorbents will add up and may justify installing oil removal equipment.