There is growing interest in possible options for treatment or reuse of flowback and produced waters from natural gas processing. Here we investigated the fouling characteristics during microfiltration of different flowback and produced waters from hydraulic fracturing sites in the Marcellus shale. All samples caused severe and highly variable fouling, although there was no direct correlation between the fouling rate and total suspended solids, turbidity, or total organic carbon. Furthermore, the fouling of water after prefiltration through a 0.2 μm membrane was also highly variable. Low fouling seen with prefiltered water was mainly due to removal of submicron particles 0.4-0.8 μm during prefiltration. High fouling seen with prefiltered water was mainly caused by a combination of hydrophobic organics and colloidal particles <100 nm in size (quantified by transmission electron microscopy) that passed through the prefiltration membranes. The small colloidal particles were highly stable, likely due to the surfactants and other organics present in the fracking fluids. The colloid concentration was as high as 1011 colloids/ml, which is more than 100 times greater than that in typical seawater. Furthermore, these colloids were only partially removed by MF, causing substantial fouling during a subsequent ultrafiltration. These results clearly show the importance of organics and colloidal material in membrane fouling caused by flowback and produced waters, which is of critical importance in the development of more sustainable treatment strategies in natural gas processing.
|Original language||English (US)|
|Number of pages||9|
|State||Published - Aug 1 2016|
Bibliographical noteFunding Information:
This research was funded by a Penn State College of Engineering Innovation Grant and a seed grant through the Center for Collaborative Research in Intelligent Gas Systems (CCRINGS) program funded by General Electric (GE). The authors would like to thank CONSOL Energy Inc. for providing the water samples. The authors acknowledge the use of the Penn State Materials Characterization Lab and the Huck Institutes of the Life Science electron microscopy shared facilities and are grateful for the technical support offered by the staff, including Trevor Clark, Julie Anderson, Dustin Hess and Missy Hazen. The Kappe Environmental Engineering laboratories provided TOC measurement instrumentation and technical assistance was provided by David Jones. Water samples were analyzed in the Penn State Water Quality lab. The authors also appreciate Patrick Saboe for assisting in initial TEM method development and Anurag Sen and Ben Farina for helping with the filtration experiments.
© 2016 Elsevier Ltd.
- Flowback water
- Hydraulic fracturing
- Membrane fouling
- Natural colloidal characterization
- Produced water