Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals widely used in industrial and consumer products for their resistance to heat, water, and oil. However, PFAS are persistent in the environment and have been linked to adverse health effects, earning them the nickname “forever chemicals.”
AIMEQUIP provides advanced PFAS treatment systems tailored for industrial and municipal applications. Our solutions are engineered to remove PFAS from contaminated water streams efficiently and reliably, meeting stringent environmental regulations. Here is a detailed overview of the different PFAS treatment technologies:
Granular Activated Carbon (GAC) Filtration
Granular Activated Carbon (GAC) is one of the most used technologies for PFAS treatment, especially for drinking water and groundwater remediation. It works through the process of adsorption, where PFAS molecules physically adhere to the porous surface of carbon granules. GAC is highly effective at removing long-chain PFAS compounds such as PFOA and PFOS due to their stronger hydrophobic interactions. The effectiveness of GAC is influenced by factors like empty bed contact time (EBCT), carbon source (bituminous vs. coconut shell), water pH, and the presence of competing organic compounds. However, short-chain PFAS compounds tend to pass through GAC beds more easily and may require polishing stages or more frequent media changes. Despite this, GAC remains a widely accepted and cost-effective first-line technology for PFAS removal in municipal and environmental settings, often configured in lead-lag vessels for optimized media use.
Performance Factors:
- Contact Time (EBCT): Longer Empty Bed Contact Time increases removal efficiency.
- Carbon Type: Bituminous coal-based GAC generally performs better than wood-based for PFAS.
- Pre-treatment: Turbidity, natural organic matter (NOM), and competing ions can reduce capacity.
- Breakthrough Curves: Need to be monitored to schedule media change-out before PFAS leakage.
Ion Exchange Resin Systems
Ion exchange systems use synthetic polymer beads functionalized with ionic groups that selectively attract and bind PFAS compounds from water. Unlike GAC, which relies on passive surface adsorption, ion exchange uses electrostatic attraction to actively remove both long- and short-chain PFAS molecules. These resins, particularly those designed with hydrophobic backbones, exhibit high affinity for PFAS and typically offer faster kinetics and higher capacity than GAC. Because ion exchange systems can be customized to target specific contaminants, they are well-suited for industrial wastewater, landfill leachate, and sites with complex PFAS mixtures. As a proven PFAS treatment method, the resins can be housed in compact vessels, allowing for a smaller footprint and easier integration into existing treatment infrastructure. However, resin fouling from organics or scaling components like iron or calcium must be managed through pre-treatment. Depending on the type of resin, spent media can either be regenerated or disposed of as hazardous waste. Ion exchange is particularly valuable when footprint, efficiency, and treatment of short-chain PFAS are key concerns.
Performance Factors:
- Resin Selectivity: Anion-exchange resins with hydrophobic matrices are most effective for PFAS.
- Flow Rate: Lower flow rates improve ion exchange kinetics.
- pH Sensitivity: Neutral to slightly basic pH optimizes performance.
- Regeneration Complexity: Some resins allow regeneration; others require incineration.
Reverse Osmosis (RO) and Nanofiltration (NF)
Reverse Osmosis (RO) and Nanofiltration (NF) are pressure-driven membrane technologies that physically exclude PFAS compounds based on molecular size and charge. RO, in particular, is capable of rejecting over 99% of known PFAS species, making it one of the most comprehensive PFAS treatment options available. In RO systems, water is forced through a semi-permeable membrane, leaving contaminants behind in a concentrated brine stream. This makes it highly effective not just for PFAS but also for a broad spectrum of other pollutants like dissolved salts, heavy metals, and organics. However, the rejected brine produced must be carefully managed, as it contains a high concentration of PFAS and other contaminants. RO systems require extensive pre-treatment to prevent membrane fouling, including filtration, softening, and sometimes anti-scalant dosing. Though capital-intensive and energy-demanding, RO is ideal for applications where water purity is critical, such as industrial reuse or potable water supply. Nanofiltration, which operates at lower pressures and has larger pore sizes, may be used for partial PFAS rejection in less stringent applications.
Performance Factors:
- Membrane Type and Pore Size: RO membranes typically remove >99% of PFAS.
- System Recovery Rate: Higher recovery can increase concentration in reject stream, leading to fouling.
- Pre-treatment: Required to protect membranes from fouling by organics, particulates, and hardness.
- Concentrate Handling: PFAS-rich brine requires secure disposal or further treatment.
Advanced Oxidation Processes (AOPs)
Advanced Oxidation Processes (AOPs) are designed to chemically degrade organic contaminants through the generation of highly reactive radicals, such as hydroxyl (•OH) and sulfate (•SO₄⁻) radicals. Common AOP methods include combinations like UV/H₂O₂, ozone/H₂O₂, and UV/persulfate, which produce radicals capable of breaking down complex and otherwise persistent chemicals. However, PFAS are among the most chemically stable substances known, and traditional AOPs have limited efficacy in destroying fully fluorinated compounds like PFOA or PFOS. Instead, AOPs are more successful in breaking down PFAS precursors—compounds that degrade into PFAS—and other co-contaminants. They are often used as a polishing step after GAC, ion exchange, or RO to treat trace-level residuals or precursors that might otherwise escape removal. AOP systems require careful control of oxidant dosage, reaction time, and water chemistry to be effective, and energy demands can be high due to the need for UV light or ozone generation. Despite these challenges, AOPs are valuable when integrated into multi-stage PFAS treatment systems.
Performance Factors:
- Water Matrix: High organic content can scavenge radicals, reducing efficiency.
- Target Contaminants: AOPs are best used for precursors and co-contaminants rather than primary PFAS removal.
- Process Optimization: Requires careful balance of oxidant dose, pH, and contact time.
Thermal Destruction and High-Temperature Treatments
Thermal destruction remains the only method that guarantees complete and irreversible breakdown of PFAS molecules. At extremely high temperatures, typically above 1,000°C, carbon-fluorine bonds are broken down into inert compounds such as carbon dioxide, water, and hydrofluoric acid (HF). Technologies such as rotary kiln incineration, plasma arc destruction, and supercritical water oxidation (SCWO) are used to handle PFAS-laden waste, including spent GAC, ion exchange resins, sludge, or reverse osmosis brines. These PFAS Treatment methods are especially critical for “end-of-pipe” management, where concentrated PFAS waste must be destroyed rather than simply transferred or contained. Plasma arc systems, in particular, offer advanced control and low emissions, making them suitable for high-purity destruction. However, the operational complexity, high energy costs, and need for air emission controls make thermal treatment best suited for centralized or specialized facilities. AIMEQUIP’s systems can be configured to pre-treat, dewater, and package PFAS waste streams for secure transport to approved thermal facilities.
Performance Factors:
- Temperature & Residence Time: Must be sufficient to ensure complete destruction.
- Air Pollution Control: Required to capture acid gases and fluorinated by-products.
- Feedstock Characterization: Must be known to prevent hazardous emissions.
Selecting the Right PFAS Treatment Technology
The optimal PFAS treatment system depends on multiple factors:
Factor | GAC | Ion Exchange | RO/NF | AOP | Thermal |
Long-chain PFAS | ✅✅✅ | ✅✅✅ | ✅✅✅ | ⚠️ | ✅✅✅ |
Short-chain PFAS | ⚠️ | ✅✅ | ✅✅✅ | ⚠️ | ✅✅✅ |
Precursor removal | ⚠️ | ⚠️ | ✅ | ✅✅ | ✅✅✅ |
Waste volume generated | Medium | Low | High | Low | Low |
Energy consumption | Low | Low | High | Medium | High |
CAPEX/OPEX | Low-M | Medium | High | Medium | High |
Final destruction | ❌ | ❌ | ❌ | Partial | ✅✅✅ |
AIMEQUIP’s Integrated Approach
AIMEQUIP designs integrated PFAS treatment trains that combine technologies to meet site-specific goals. For example:
- GAC + Ion Exchange for drinking water plants
- RO + AOP for industrial reuse with precursors
- GAC + Thermal Destruction for landfill leachate with media offloading
- Mobile Skid Units for emergencies or pilot testing
All systems are available as pre-engineered modular skids, containerized packages, or full-scale custom-built plants. Control systems include automated PLCs, telemetry, and SCADA integration for remote support and monitoring.
Why Choose AIMEQUIP?
- Expertise: Our team has extensive experience in designing and implementing water treatment solutions.
- Customization: We tailor our systems to meet specific client requirements and site conditions.
- Compliance: Our solutions adhere to the latest environmental regulations and standards.
- Support: We offer end-to-end services, from design and installation to maintenance and support.
Ready to tackle PFAS contamination at your site? Get in touch with AIMEQUIP to speak with our treatment specialists, request a technical consultation, or arrange a pilot unit.