Electro-Oxidation to Destroy PFAS in Effluent Streams
This technology is based on the use of long-lasting boron-doped-diamond electrodes generating hydroxyl radicals to destroy PFAS in water without the use of chemicals and without producing waste.
WSP’s EO has been successfully tested to destroy PFAS below the US EPA Drinking Water Health Advisory Levels, the Health Canada Criteria and several more stringent standards. The technology is effective for all types of PFAS, scalable, long-lasting and typically treats PFAS in one to two hours, thereby making the technology highly efficient with minimal operation and maintenance requirements. The technology has been successfully tested and optimized in the lab on several effluents and is being used for commercial applications.
The development work has been done in collaboration with the department of Civil Engineering from McGill University.
Ball Milling to Destroy PFAS in Soil
In this research we have partnered with Queen’s University, Royal Military College of Canada and a global Oil and Gas corporation to destroy PFAS in soil using ball milling. This technique is showing very promising results, with significant destruction of all the PFAS measured in laboratory and using field soils. WSP is now working with the research team on further optimization, scaling and field implementation. A patent application has been filed.
More Treatment Tools for the Environmental Industry
To offer a wider range of solutions to the environmental industry to complement destructive technologies, WSP has started a new applied research and development project. Its objective is the development of innovative, cost-effective, and sustainable approaches based on the use of clay minerals for in situ and ex situ treatment of PFAS impacted ground- and surface water, wastewater, soil, and sediment.
We are working with McGill University in Canada, Newcastle University in the UK and CETCO/Mineral Technologies Inc. in the US to develop a new approach that uses reactive and self-regenerating Fe-containing clay minerals for remediation of PFAS source zones via radical-accelerated PFAS degradation. In parallel, we will advance the modified bentonite adsorbents technology to demonstrate that low-cost clay adsorbents are superior alternatives to other sorbent materials with high fouling resistance.
We are also supporting Queen’s University and the Royal Military College of Canada on the feasibility of biodegradation of PFAS utilizing white rot fungi and to identify the key mechanisms and optimization for the destruction of PFAS at high temperatures.
Innovation on PFAS Testing, Fate and Transport, and Risk Assessment
We have been investing to enhance the knowledge on PFAS fate and transport, development of alternative testing and analytical tools as well as identification of supporting tools for efficient risk assessments:
- PFAS transport in porous media: The adsorption of PFAS at air-water interface has become known to critically affect PFAS transport. This is relevant for contaminant transport in the unsaturated zone as well as in the saturated zone where trapped gas can be created by natural processes and remediation-based mechanisms. We supported Queen’s University to investigate the effects of trapped gas bubbles on PFAS contaminant transport in puros media and assessment of competition between PFAS for adsorption to the air-water interface.
- PFAS Passive Sampler: The development of a PFAS passive monitoring method represents a ground-breaking advance for site and risk assessments to measure the dissolved PFAS fraction that drives toxicity. To support this, we assisted with testing and development of an equilibrium passive sampler for the measurement of ionic and neutral PFAS in groundwater, surface water and pore water. Other advantages for this type of sampler include improved detection limits, no disturbance of water column, lower risk of cross-contamination, less time in the field and no water disposal.
- New Analytical Tools and Better Understanding of Toxicity Drivers: This research includes developing and optimizing analytical protocols for measurement of total organic fluorine at lower detection limits as a reliable and cost-effective screening tool; understanding the fate of structurally different PFAS by studying mobility and parameters affecting speciation; investigating toxicity drivers and establishing effect-oriented chemical and biological analysis using mechanistic studies and metabolomics to support risk assessments.
