Membrane Processes in Water Treatment and Wastewater Reclamation: Commercialization Landscape, Innovations, and Emerging Trends

Recent Evolution of RO Emerging Niches High Recovery Desalting with Scaling Control High Recovery Brine Concentration (Step toward Zero Liquid Discharge (ZLD)) RO Membranes High Permeability RO Low-Fouling RO (Surface Modification) Chlorine Resistant RO Boron Selective RO Ultra-High Pressure RO (UHP-RO) {Brine Concentration Process} RO Spacer Design {3-D Printed Spacers} 7 Membranes in Desalination and Brine Management Seawater Seawater RO (SWRO) Post-SWRO BWRO for Boron Removal Pretreatment: MF or UF (often UF w/o coagulant) Recent Demonstration Work on Ceramic UF MF or UF + SWRO: IMS (Integrated Membrane System) Work on NF Pretreatment (Scaling Reduction) for SWRO Brackish Water Brackish Water RO (BWRO) Electrodialysis (ED) or ED Reversal (EDR) Brine Management Inland Brines → Zero Liquid Discharge (ZLD); Membrane Processes for Brine Concentration and ZLD Coastal Brines → Safe Environmental Disposal via Outfalls New Perspective: Valorization of Brines for Recovery of Valuable Materials → e.g., Lithium; Membrane Processes for Brine Concentration, ZLD, Selective Recovery 14 Partial Desalting: A New Paradigm for Agricultural Sector Irrigation Water for Cultivation University of California of Salt-Tolerant Crops (Halophytes) Salinity Management Salt Tolerance Increased through Breeding or Grafting (e.g., tomatoes) Abundance of Saline and Brackish Waters: Bays, Estuaries, River Deltas, Coastal and Inland Groundwaters, Geothermal Brines, etc. Potential Processes Nanofiltration (NF) Electrodialysis (ED) Focus on New NF and ED Membranes and Different-Objective Operating Conditions Besides Overall Salinity Ions Detrimental to Plant Growth (e.g., Na+, Cl-, H BO -) 2 3 Ions Beneficial to Plant Growth (e.g., K+, Ca2+, Mg2+) Targeting Specific Ions Ion Properties: Size (Hydrated Radius), Ionic Charge NF Membrane Properties: Pore Size and Surface Charge ED Ion Exchange Membranes: Mono-Valent vs. Membranes in Wastewater Reclamation ⇒ (Wastewater Reuse) Cost < 50% of Sea Water Desalination; Energy < 50% of Sea Water Desalination Tertiary Membrane Filtration (post CAS) → MF, UF (OCWD) WWRO → Post UF or MF (IMS); Challenge: Increased Recovery (PUB) NeWater (PUB) Membrane Bioreactor (MBR); MBR-WWRO (+ UV)⇒ Direct Potable Reuse 18 Innovations and Future Trends Computational and Synthetic Chemistry in Membrane Material Design Bioinspired Membrane Materials (e.g., selective biosurfactant functionalities) Enhanced Selectivity Membranes (rejection or recovery) 3-D Printing of Module Components Process Performance Models AI/ML Driven Membrane Operation Membrane-Based Zero Liquid Discharge (ZLD) Approaches SWRO Brine Mining Partial Desalting for Agriculture Renewable Energy Driven Membrane Processes (lower carbon footprint) Reuse of End-of-Life Membranes (e.g., RO for UF) 28.