Oasys is working with National Oilwell Varco to offer its forward-osmosis solution to shale oil and gas companies in the Gulf of Mexico. And in China, where the start-up has signed a deal with Beijing-based Woteer Water Technology, Oasys is in the final throes of delivering its first "zero liquid discharge" project to clean every gallon of contaminated water 100 percent of the way to potable drinking water.
"We're providing a much more cost-effective, robust, simple approach," said CEO Jim Matheson, a former Navy pilot who took on the lead role at Oasys Water in 2013.
Hydraulic fracturing, better known as fracking, is the process by which oil and gas companies inject a cocktail of water, sand and chemicals underground to release and extract gas trapped deep in shale formations. But it's a process plagued with environmental concerns.
"Along with chemicals in the fracking fluids, heavy metals—arsenic, barium, cadmium—are the biggest problem with fracking," said Mark J. La Guardia, an environmental research scientist at the Virginia Institute of Marine Science at the College of William and Mary. "These metals are dislodged from shale during the fracking process."
Typically, such wastewater is purified through capital- and energy-intensive boiling and desalination processes. In the past, hulking thermal systems were used. Think of a big pot that boils the wastewater and leaves the solids behind while distilling the water. Today this process has been largely replaced by a reverse-osmosis method, which cheats the osmotic principle of biology by which water moves from a dilute solution to a concentrated one. In reverse osmosis, a thin semipermeable membrane and a tremendous amount of hydraulic pressure are used to push water out of the wastewater on one side of the membrane and into clean water on the other side of the membrane.
"You need a lot of electricity to pump the pressure to make this flow happen," said Menachem Elimelech, a professor in the department of chemical and electrical engineering at Yale University. What's more, Elimelech said, polluted water that's high in salinity, like that left over from fracking, requires such high hydraulic pressure that the membrane will often break.