(88e) Recycling Wastewater for Hydraulic Fracturing

Authors: 
Cleous, H., University of Arkansas

Hydraulic fracturing is the use of water to recover natural gas and oil. This process uses approximately 5 million gallons of water per well and is unsustainable. The treatment and recycle of hydraulic fracking water is an engineering best practice not only from an environmental standpoint, but also from an economic standpoint. The current disposal method of deep well injection is a costly and ineffective solution. If frac water is treated and recycled, the savings in water and disposal fees would not only pay for the water treatment program, but also give a return on investment of approximately 30%.

Wastewater treatment options may range from traditional chemical precipitation to evaporation to membrane systems such as Nano filtration, a VSEP system, ultrafiltration, or reverse osmosis. Depending on purity requirements, water treatment methods may be placed in parallel or used independently.

My work has been exploring some of these different membrane treatment options, with a focus in Nano filtration, and doing a full scale design of the economic process. To date I have found that water can be treated for less than $3 / barrel, less than the current cost of disposal. Recycle of hydraulic fracking water can make hydraulic racking more sustainable.