About 2.5 billion gallons of produced water—a byproduct from the oil refinery and extraction process—is generated each day in the United States. Handling that water is a major challenge in the oil refinery industry, particularly because it is deemed unusable for household and commercial use by the Environmental Protection Agency because of remaining contaminants.

Several commercial treatments are available, but they are expensive, do not remove all traces of contaminants from water and can be energy-intensive.

Now, Purdue University researchers have developed a process to remove nearly all traces of oil in produced water. The process uses activated charcoal foam and subjects it to solar light to produce heat and purify the water. The foam absorbs the oil contaminants from the water.

A new Purdue University process uses activated charcoal foam and subjects it to solar light to produce heat and purify produced water. Credit: Purdue University/Ashreet Mishra

The Purdue process was presented during the annual conference for the Produced Water Society in February.

The Purdue’s team process also meets all EPA standards for clean water from industrial sources and had a total organic carbon of 7.5 milligrams per liter. The oil absorbed by the foam can be recovered efficiently. The Purdue researchers were able to recover up to 95% of the oil that was absorbed.

Researchers are working with the Purdue Research Foundation Office of Technology Commercialization to patent the innovation, and they are looking for partners to continue developing it.