Available technologies, Clean Technologies, Electrical and Electronic components, Engineering, Environement, Nanotechnology

MEMBRANES FOR FORWARD OSMOSIS AND MEMBRANE DISTILLATION AND PROCESS OF TREATING FRACKING WASTEWATER

Water purification using novel thin-film composite forward osmosis membrane with high flux/antifouling properties and amphiphobic membrane distillation

The need of advanced technologies for treating water and wastewater

  • Management of fracking wastewater is crucial to shale gas development and to the preservation of the environment and human health
  • Water & Wastewater Treatment Equipment Market size was valued at USD 23.20 Billion in 2016 and is projected to reach USD 33.22 Billion by 2022, at a CAGR of 6.2% between 2017 and 2022
  • Desalination equipment is the fastest-growing product type, which is projected to register to reach 5.20 billion by 2022
  • Treatment of highly saline fracking wastewater is both challenging and energy intensive
  • Forward Osmosis is a desalination process in which a feed solution is treated by osmotic pressure rather than hydraulic pressure
  • Reverse osmosis process uses hydraulic pressure as a driving force for separation. Hence more energy is required for reverse osmosis compared to forward osmosis (the most popular water purification membrane technology)
  • Membrane distillation (MD) is an emerging technology utilizes low-grade heat or industrial waste-heat below the boiling temperature to drive separation. MD is still in its embryonic stage and has not been widely applied in industrial and commercial development due to unresolved challenges: membrane fouling and wetting
  • Existing problems with forward osmosis process: Membrane properties (low water flux and the prone to fouling), and draw solutions (low osmotic pressure at solubility and high reverse salt flux)

New designs/methods for membrane distillation and forward osmosis

  • Manufacturing superhydrophobic and amphiphobic membranes for membrane distillation comprising a microporous surface-modified mat of electrospun nanofibers
  • The nanofibers are made of a nanocomposite comprising reduced graphene oxide (rGO) dispersed in a hydrophobic polymer and are grafted with a silane coupling agent or with hydrophobic nanoparticles
  • Manufacturing a thin film composite membrane for forward osmosis membrane comprising a microporous support layer (substrate) and rejection layer formed on one side of the support layer
  • The support layer is a microporous mat of electrospun nanofibers (electrospun N6/SiO2 (20 wt.%) composite nanofiber mat (Water contact angle 15°))
  • The rejection layer (the active layer) is made of nanocomposite of hydrophilic nanoparticles
  • Pre-treatment of fracking wastewater by microfiltration or ultrafiltration
  • Technology developed by Saifur Rahaman (Department of Building, Civil, and Environmental Engineering , Concordia University)

Competitive advantages  

  • Enhanced stability and durability of membrane distillation performance in both high permeation flux and high salt rejection environments
  • Displaying superhydrophobicity with water contact angle larger than 150° and sliding angle lower than 2° indicating their self-cleaning properties
  • Excellent amphiphobic stability even after the challenging treatments including 4h boiling in deionized water, 110h etching in strong hydrochloric acid HCl and Sodium hydroxide NaOH solutions
  • Excellent wetting resistance against low surface tension liquids (diiodomethane and glycerol)
  • Robust dynamic performance with a relatively higher water flux and desired permeate conductivity in the presence of a surfactant (sodium dodecyl sulfate, SDS) through a direct contact membrane distillation (DCMD) process
  • Achieved higher wettability for the fabricated thin film composite (TFC) forward osmosis membrane
  • Higher water flux with lower specific reverse salt flux and less fouling obtained in FO for the pre-treated fracking wastewater used as feed using draw solutions
  • Separation of draw solution from pure water by membrane distillation
  • Improved antifouling propensity in the FO process
figure-3
figure-4

Market applications

  • Water and wastewater treatment
  • Purification water from highly saline feed solutions containing low surface tension substances
  • Seawater desalination and fracking wastewater treatment
  • Downstream process
  • Microfiltration/ ultrafiltration (MF/UF) separation
  • Chemical and petrochemical processing

Business opportunity

  • PCT has been filed on September 18th 2019
  • Technology available for licensing

CONTACT

If you are interested by this technology, please contact :
Jean-Philippe Valois, Director Business Development, Engineering
jpvalois@aligo.ca, (514) 575-0425

UNIVERSITY

Concordia University

Main inventors

saifur-rahaman

Saifur Rahaman, Associate Professor, Building, Civil, and Environmental Engineering

Dr. Saifur Rahaman is currently a tenured Associate Professor of Environmental Engineering at Concordia University. He received his Ph.D. from University of British Columbia (UBC), Vancouver, BC, M.A.Sc. from Dalhousie University, Halifax, NS, and B.Sc. from Bangladesh University of Engineering and Technology (BUET), Dhaka, Bangladesh, all in Civil (Environmental) engineering. His primary focus current research is to develop advanced materials and novel membrane-based processes for water and wastewater treatment. His research interest includes (i) environmental applications and implications of engineered nanomaterials, (ii) membrane separations for water and wastewater purification, (iii) electrochemical advanced oxidation for disinfection and destruction of trace contaminants, and (iv) resource recovery (water, nutrient and energy) from industrial wastewater