Wastewater may not be as dirty as it sounds…
Wastewater may not be as dirty as it sounds…
A long overlooked byproduct of extractive operations, wastewater was left to pollute local waterways or soil, often with devastating effects on local flora and fauna. In recent decades, the focus has been on its effective recycling and treatment, creating a closed water system to be used in mines or on oil rigs. However, this research has come one step further of late. The very waste within the water is being seen as a potential treasure trove of everything from oil, minerals and more besides. Research into how to extract oil from water runoff saw a particular upswing when prices were at over $100 per barrel. Research firm Lux Research estimated that 6-10 percent of oil extracted is lost to wastewater on average when drilling. “Many current wastewater streams contain resources worth billions of dollars of lost product and lost opportunity. As the value of resources rises, recovery technologies are beginning to make sense for even parts-per-million traces of materials such as precious metals and oil,” said Tess Murray, Research Associate at Lux Research and author of the report titled, “Recovering valuable resources from wastewater.”
However, interest in this technology continued as prices tumbled. At a time when exploration and production firms were under severe financial pressure, every drop of oil recovered could help. The sector for clean water technology was estimated at $600 billion in 2014, with startups rushing into the breach. The next question revolved around is the best way to do it. Established technology in the oil and gas industry was adept at separating water and oil, but usually in large quantities during spills. The fine tooth-combing needed for this precise separation lay elsewhere. Tailings recovery has long been a mainstay of the mining industry. Sifting through the mountains of earth and debris taken from a mine is a valuable way for companies to recover more precious minerals and maximize profits. The logic is simple: treat wastewater, recover minerals for recycling and clean the water for reuse. Finland has made important strides in this area, developing ways to purify water while detecting and removing even trace amounts of minerals. This has also helped scientists follow the runoff from industrial sites by linking the minerals found to their places of origin. That same logic has swept through the oil industry. In Alberta, it is now law for oil companies to fully reclaim their tailings ponds at the end of a project, forcing new technological developments.
John Brogly, the director of tailings environmental priority area with Canada’s Oil Sands Innovation Alliance (COSIA), admits “There’s already been lots of work going on to find better solutions to the tailings challenges than we currently have.” Naturally, this has led to discussions about how to maximize profitability from such operations. In an industry first, Suncor Energy in Canada managed to treat the wastewater on site with no external impact. Where Canada led, other countries soon followed. With governments ramping up their efforts to meet their obligations, according to the Paris Agreement on Climate Change, separating oil from wastewater began to look appealing. Norway, ever the environmental pioneer, has passed regulation allowing for zero discharges from oil and gas sites.
This forced oil companies to go onto a war footing, giving their R&D teams a clear goal. The results have been promising. Swiss giant LafargeHolcim has released a technique, named co-processing, which sees oil sludge recycled and reprocessed into a number of byproducts, with minerals recovered, contaminants destroyed, alternative fuel created and leftovers used to manufacture cement. The civil sector has also entered the fray. The Water Environment Research Foundation (WERF) has awarded four contracts to study various ways to extract oil and pollutants from wastewater. These showcase the array of options in play, ranging from reusing gas after methane recovery to extracting rare earth elements, which will be music to the ears of Apple and Samsung. This technology, if deployed en masse in the years to come, can also provide two advantages to the oil industry. Firstly, this will encourage more reprocessing and recycling of wastewater, allowing fracking operations to become more akin to closed systems, without continuously using up more water.
According to Dow Energy & Water Solutions, such closed systems with a fixed amount of water will open up expansion in places “where water is scarce, such as the western regions of North Dakota and southwest Texas, or near major population centers, with little oil and gas infrastructure, like Pennsylvania. This makes water recycling that much more important to reduce the impact of hydraulic fracturing on local water resources, as well as infrastructure.” Secondly, this can provide a fortunate meeting point between lower expenditure and increased environmental benefits. One oil operator asked oilfield water infrastructure firm, BNN Energy, to help it reuse 100 percent of its water. A new water treatment plant was promptly built, with five top-of-the-range filters, with the client increasing recycled produced water from 30 to 100 percent, and dropping operating costs by 60 percent.
These closed systems will help to remove another risk. There have been real concerns that water recycled from oil operations poses a health risk for the population, given the noxious and potentially carcinogenic chemicals used in extraction. A California team found at least 22 toxic chemicals out of a list of 173 being used in oil extraction last year. This technology is blooming at just the right time. Water scarcity is a growing concern around the world and its often wasteful use has put oil and gas practices in the spotlight. Increasingly diverse and specific techniques to recycle wastewater while extracting everything from oil to phosphorus provide as many incentives for private companies to evolve, both as model corporate citizens and as innovative players.
SEE MORE: Dirty water = clean energy by Robin Wylie