PFAS contamination is now a regulatory priority across the EU, UK, and North America. This guide covers the engineering options for removal and destruction — from GAC adsorption to electrochemical advanced oxidation.
The regulatory landscape tightened significantly in 2024–2025. Understanding which limits apply to your site is the first step.
EU Drinking Water Directive (2021/2115): Total PFAS limit of 0.10 µg/L; sum of 20 specific PFAS 0.10 µg/L. Member states must achieve compliance by 2026. PFAS 4 (PFOA + PFOS + PFNA + PFHxS) limit: 0.02 µg/L. The UK Drinking Water Inspectorate has adopted equivalent standards post-Brexit.
Per- and polyfluoroalkyl substances (PFAS) are a group of >4,700 synthetic chemicals characterised by extremely strong C–F bonds. They are extraordinarily persistent (“forever chemicals”), bioaccumulative, and linked to thybenefitsd disruption, immune suppression, and cancer. Sources include AFFF firefighting foams, non-stick coatings, food packaging, and industrial process chemicals.
Water utilities abstracting from groundwater or surface water near military sites, airports, fire training areas, or industrial estates. Industrial dischargers in the chemical, coatings, semiconductor, and textile sectors. Sites seeking a discharge consent renewal after 2024 should assume PFAS testing will be required.
Before technology selection, a full PFAS screen (LC-MS/MS, EPA Method 533 or equivalent) is essential. Short-chain PFAS (C4–C6) behave differently from long-chain (C8 +); some technologies effective against PFOS/PFOA perform poorly on PFBS, PFHxA, and GenX. Contact us to arrange a treatability study.
PFAS removal is rarely achieved by a single technology. We design integrated trains combining pre-treatment, adsorption, and destruction stages to meet your specific regulatory limits and cost targets.
| Technology | Long-chain PFAS (C8+) | Short-chain PFAS (C4–C6) | Energy | Residual | Best Application |
|---|---|---|---|---|---|
| GAC Adsorption | >90% | 40–70% | Very low | Spent carbon (regeneration or disposal) | Drinking water, groundwater |
| Ion Exchange (IX) | >98% | >90% | Very low | Spent resin brine | Low-volume high-value |
| Nanofiltration (NF) | >95% | 60–85% | Medium | Concentrated reject | Potable WTP polishing |
| Reverse Osmosis (RO) | >98% | >90% | High | Concentrated reject (ZLD needed) | Industrial, landfill leachate |
| UV/H&sub2;O&sub2; AOP | Partial | Poor | Very high | Transformation products | Not standalone — polishing only |
| Electrochemical Oxidation | Destruction >99% | Destruction >99% | Very high | Fluoride, CO&sub2; | Concentrate destruction |
| Sonochemical / plasma | Destruction >99% | Destruction >99% | Extremely high | Mineralisation | Research / specialist streams |
PFAS treatment is rarely a single-technology solution. The following trains reflect current best practice for common scenarios.
Coagulation → Filtration → GAC contactors (EBCT 10–20 min) → Disinfection. Carbon replacement/thermal regeneration at breakthrough. Achieves <0.05 µg/L total PFAS. Cost-effective for high-flow, predominantly C8 + contamination.
Coagulation → Single-use Ion Exchange (PFAS-selective resin) → UV disinfection. Single-use IX avoids the brine management problem of regenerable IX. Suited to small communities and package WTPs where operator resource is limited.
Coagulation/DAF → RO (90–95% recovery) → Electrochemical oxidation of RO concentrate (destruction). RO permeate to drain or reuse; concentrate volume minimised before destruction. Achieves zero PFAS discharge without landfill residual.
Biological treatment → NF or RO → GAC polishing on permeate → Discharge. Concentrated reject to licensed hazardous waste. Nanofiltration removes divalent PFAS preferentially; GAC mops up short-chain breakthrough.
Concentrate management is the critical design constraint. RO and NF reject streams concentrate PFAS 5–20× feed levels. Unless electrochemical or thermal destruction is incorporated, these concentrates require licensed hazardous waste disposal — a significant ongoing operating requirement. Engage our engineers at the feasibility stage to model the full mass balance before committing to a technology.
| Parameter | Typical Value | Notes |
|---|---|---|
| EBCT (Empty Bed Contact Time) | 10–20 minutes | Lower EBCT risks early breakthrough; pilot testing essential for short-chain PFAS |
| Carbon grade | Coal-based bituminous, 8×30 or 12×40 mesh | Bituminous outperforms coconut for PFAS; micropore volume matters less than mesopore |
| Lead-lag configuration | Two contactors in series | Allows carbon exchange of lead vessel at breakthrough while lag vessel continues treatment |
| Typical carbon life (long-chain) | 12–30 months | Highly dependent on PFAS loading, DOC competition, and flow rate |
| Thermal regeneration PFAS recovery | >99% destruction at >850°C | Must be performed at PFAS-licensed thermal treatment facility |
| Backwash frequency | As per headloss only | Excess backwashing desorbs PFAS and reduces capacity — minimise frequency |
Granular activated carbon filter design, operation, and regeneration for trace contaminant removal.
View GAC SystemsPFAS, pharmaceuticals, microplastics, and endocrine disruptors in water treatment.
Emerging ContaminantsHigh-rejection RO systems for industrial PFAS containment and permeate reuse.
View RO SystemsPFAS treatability studies to validate technology selection before capital commitment.
Pilot TestingOur process engineers will evaluate your application and recommend the optimal solution for your flowrate, quality targets, and budget.
Our expertise spans multiple industries with sector-specific water treatment solutions.