Meeting the PFAS Challenge with High-Recovery Flow Reversal RO (FR-RO)
PFAS contamination continues to be a growing concern for municipal water treatment and industrial wastewater applications. With stricter PFAS regulations, rising disposal costs, and increasing public awareness, utilities are under pressure to deploy reliable, future-proof treatment solutions.
At the Georgia Association of Water Professionals (GAWP) conference and the Alabama Water and Pollution Control Association (AWPCA) conference, ROTEC’s Head of U.S. Sales, Max Finder, delivered an in-depth presentation on ROTEC’s proven PFAS treatment capabilities. The presentation highlighted results from over 10 pilot programs conducted across the United States, demonstrating consistent non-detect PFAS removal and stable operation at recovery rates of up to 95%. These pilots, carried out in many states including Georgia, North Carolina, New Jersey, and Alabama, showcase how FR-RO maintains performance across varying feedwater qualities and operating conditions, establishing it as a reliable, scalable solution for full-scale PFAS treatment systems.
While granular activated carbon (GAC) and ion exchange (IX) are widely used, they often struggle with breakthroughs on short-chain PFAS and require frequent media changeouts, adding significant OPEX and disposal costs. Reverse osmosis (RO) provides a stronger, more consistent barrier against both short- and long-chain PFAS while also removing other emerging contaminants like 1,4-Dioxane, pharmaceuticals and nanoplastics.
Reverse osmosis membrane systems have become a leading solution for PFAS removal, particularly when facilities face high levels of contamination, including compounds like PFOS and PFOA. It’s especially effective in situations where short-chain PFAS must be completely removed or when total organic carbon (TOC) levels are high, e.g. in surface water treatment applications, as trucking, disposal and replacement costs for spent media are rising and unpredictable.
Limitation of Conventional RO Systems
While RO removes PFAS, scaling and fouling challenges limit its performance at higher recovery rates. In conventional RO:
- Scaling increases chemical cleaning frequencies (CIP) and shortens membrane life
- Permeate quality declines under heavy fouling conditions
- Operating pressures rise, increasing energy consumption
These constraints often keep recovery rates around 75–80%, resulting in higher brine volumes and increased waste management costs.
Flow Reversal RO (FR-RO): A Future-Proof Solution
FR-RO technology overcomes the scaling and fouling challenges that limit conventional RO performance by combining patented flow reversal and block rotation. This solution delivers stable, ultra-high recovery rates even on challenging waters. It provides the most reliable barrier against PFAS and other emerging contaminants (CECs) while achieving the lowest 20-year lifecycle operating costs, making it a future-proof RO technology for municipalities and industries.
How it Works:
- Flow Reversal: Periodically reverses the direction of feedwater through the membranes, changing conditions and resolubulizing any scale particles that might have formed before they can take hold and proliferate.
- Block Rotation: Alternates which membrane block handles the highest concentration stage, distributing fouling stress evenly – similar to “rotating the tires” on a car.
Together, these techniques keep membranes cleaner, extend their life, and stabilize performance- enabling consistent operation even under high TDS and silica conditions.
What you’ll get:
- Ultra-high Recovery Rates: up to 97% recovery when treating PFAS and other contaminants with brine reduction of up to 80%
- Operational Efficiency: Fewer chemicals, including acids and anti-scalants and reduced CIP and downtime.
- Sustainable Solution: Reduces chemical and energy consumption, supports Zero Liquid Discharge (ZLD) goals by minimizing brine volumes helping facilities reach their environmental goals.