Forward Osmosis Technology: Applications for Reducing Produced Wastewater Volumes in the Hydraulic Fracturing Industry

Abstract

The main objective of this research is to further understand the effectiveness of the forward osmosis process as a possible volume reduction method for hydraulic fracturing operation produced waters. In order to broaden knowledge about this technology, I conducted a series of experiments, adapted from previous studies, utilizing a laboratory bench scale forward osmosis unit, the Sterlitech CFO42DFO cell. The experiments focus on two variables central to the forward osmosis process, the draw and feed solutions. The first set of experiments center on varying the type of draw solution (NaCl, KCl, and MgCl2) and observing the effects on water flux across the membrane. The second set of experiments focus on varying the feed solutions in order to mimic the major element concentrations of shale gas operations produced waters from around the United States. It was determined through my experimentation that NaCl was most effective, among the draw solutions tested, in achieving the largest water flux. In addition, the forward osmosis process alone was not sufficient in reducing the volumes for each produced water composition due to non-favorable osmotic pressure differentials as well as effects from internal concentration polarization.