A breakthrough in oil spill cleanup technology has now been adapted for wastewater treatment use. The oil skimming technology, developed by Elastec in 1990, allows the use of a plastic drum device to skim floating oil from the water’s surface quickly and efficiently. The oil is attracted to plastic, while water isn’t.

The wastewater version is called THE DUKE FOG Maintenance System. According to Linda Henning, Elastec’s marketing director, the device is designed to skim fats, oils, and grease in the cell of the primary treatment process.

“THE DUKE will actually separate the skimmed oil material into a holding tank, where it can then be properly disposed of,” she says. “FOG is an increasing problem in wastewater treatment, and we believe this technology can help alleviate it.”

The skimmer’s drums rotate using an hydraulic power unit at a calibrated speed that picks up FOG and very little water. When the material is accumulated on the skimmer’s wiper blades, the vacuum pump engages and runs for a preset time, suctioning the collected FOG into a separation tank. The vacuum pump continues to run for a set time frame to empty the skimmer of material. Once the cycle ends, it is repeated based on predetermined and adjustable time settings.

“We view THE DUKE FOG skimmer system as a cost/benefit for the treatment plant to lower chemical and filter maintenance expense,” Henning says. “The system is showing promising results in reducing total suspended solids (TSS) and toxic hydrocarbons.”

The tank portion of THE DUKE has two compartments — a vacuum portion on top and a water storage portion underneath. When the vacuum pump is engaged, a ball check valve seals the top portion from the bottom, creating vacuum pressure to separate the FOG from any water that is collected, which is very little. The bottom portion is vented, and the collected water circulates to wash the FOG from the skimmer’s trough to the vacuum hose. When the cycle is complete, the valve opens, and water refills into the bottom portion of the tank. When the tank is full, the FOG can be vacuumed and hauled away.

“We see THE DUKE as a solution to lessening the accumulation of fats, oils, and grease that reach a wastewater treatment facility from restaurants and stormwater runoff — and in turn, it will produce cleaner effluent into the receiving water environment,” Henning says. 618-382-2525; www.elastec.com