Desalination, Vol.442, 51-61, 2018
Closed circuit desalination of O&G produced water: An evaluation of NF/RO performance and integrity
Reclamation and reuse of oil and gas (O&G) waste streams is being considered as an option to alleviate stress on freshwater supplies. While limited treatment is necessary to reuse O&G wastewater (e.g., produced water (PW)) for subsequent hydraulic fracturing, high removal of organic matter and total dissolved solids (TDS) is needed to enable broader reuse (e.g., irrigation, stream flow augmentation). This study focused on the use of closed circuit desalination with nanofiltration (NF) and reverse osmosis (RO) to remove TDS and organic matter from pretreated PW. The performance and fouling propensity of three commercial NF and RO membranes was compared during the concentration of 900 feed batches (440 h). Up to 99.6% TDS and 89% dissolved organic carbon (DOC) was removed, producing high quality permeate. Membrane characterization revealed minimal scaling and organic fouling of the three membranes, suggesting that closed circuit desalination (CCD) might be a promising method to facilitate reuse of PW.
Keywords:Closed circuit desalination;Nanofiltration;Reverse osmosis;Membrane integrity;Produced water;Membrane fouling