A new step that removes salt from the water that is used for the fracking process makes the water reusable. Researchers at MIT and in Saudi Arabia can now add a new step to fracking called electro dialysis.
Produced water from fossil-fuel wells can have salinity three to six times greater than that of seawater; the new research indicates that this salt can be effectively removed through a succession of stages of electro dialysis.
The idea would not be to purify the water sufficiently to make it potable, the researchers say. Rather, it could be cleaned up enough to enable its reuse as part of the hydraulic fracturing fluid injected in subsequent wells, significantly reducing the water needed from other sources.
Lienhard explains that if you’re trying to make pure water, electro dialysis becomes less and less efficient as the water gets less saline, because it requires that electric current flow through the water itself: Salty water conducts electricity well, but pure water does not.
While the electro dialysis technology is available, new fracking equipment is needed that will utilize the new step. This new step will help recycle water that can be used again for fracking and will draw less resources from water starved states like Texas.