Per- and polyfluorinated alkyl substances (PFAS) have been used in industry for decades. The spectrum ranges from coated pans to water-repellent textiles and fire-fighting foams. The problem: PFAS are chemically extremely stable and almost impossible to break down biologically. Drinking water sources, rivers, groundwater and soils are now contaminated worldwide.

This means a growing responsibility and an urgent need for action for the industry and municipal utilities, not only due to increasing legal limits, but also due to social pressure. Although traditional methods such as activated carbon or ion exchange can filter out some PFAS, they are ineffective at high contamination levels or when certain types of molecules are present. Furthermore, these processes produce significant amounts of contaminated waste that is challenging to treat.

“We are very actively involved in combatting PFAS, constantly working on new technologies and solutions. The SAFF^® technology is the first available process based on a natural physical mechanism that combines simplicity, efficiency and sustainability,” explains CEO Per O. Bjöörn.

The SAFF^® process is based on a simple principle: it specifically separates PFAS from water (separative), and focuses exclusively on these pollutants (selective) without capturing large quantities of other substances at the same time. This results in a comparatively small volume of contaminated concentrate.

The method is based on the flotation principle: Air bubbles are introduced into the water in the knowledge that PFAS molecules will attach themselves to the surface of such bubbles. Together with the bubbles, they form a stable foam that settles on the surface of the water and can be removed. The result is virtually PFAS-free water and a PFAS-rich foam. This foam undergoes further compaction in an integrated post-treatment step. This increases the concentration of pollutants and significantly reduces the residual volume to be disposed of. What does that mean in concrete figures?
· Approximately 5 m³ of concentrated PFAS waste is produced for every 100,000 m³ of treated landfill water.
· For 100,000 m³ of groundwater, this amounts to a volume of around 50 litres of concentrated PFAS waste.

Focusing on the best solution

“Our goal is to collaborate with our customers to find the optimal solution to every challenge. That’s why we start joint projects with a comprehensive technical analysis and laboratory tests,” Per O. Bjöörn explains. The next step is to initiate a pilot project, the results of which will then be included in the decision as to which system will be implemented in practice.

Flexibel einsetzbar

ACAT offers a range of different types of treatment systems. The “workhorse” is SAFF^®40, which is housed in a 40-foot shipping container. SAFF^®40 is suitable for locations with high volumes of contaminated water. Up to 40 m³ can be treated per hour. SAFF^®20 has been designed specifically for short-term projects and locations with lower flow rates. SAFF®10 is the perfect solution for projects where space is limited.

Internationally proven technology

The SAFF^® process has long since moved beyond the pilot stage. With over 45 installations worldwide, including more than 15 in Europe alone, the technology has proven its worth. “Whether it’s the treatment of landfill leachate or groundwater remediation, SAFF® has impressively demonstrated its ability to remove PFAS effectively and sustainably in everyday use,” says Per O. Bjöörn, providing a thoroughly positive assessment of the experience to date.

Where is SAFF® used?

Landfill leachate

Landfills contain various substances that are flushed out by rain. The result is highly complex wastewater that can contaminate groundwater, thereby also contaminating our drinking water. The SAFF^® process is ideal for this situation because it selectively separates PFAS, and existing mechanisms can be used to treat all residual materials. This is extremely economical and saves costs.

Groundwater

The purification of drinking water is often carried out using groundwater or spring water. The SAFF^® process uses a natural process and does not require any additional chemicals. This allows PFAS pollutants to be removed in a targeted manner, without affecting the quality of the water with additional auxiliary materials.

Reverse osmosis

Existing processes often result in high-volume concentrates containing the filtered-out pollutants. Disposal costs are high because they depend on volume. The SAFF^® process can significantly compact the concentrate, thereby reducing the volume that needs to be disposed of. This increases efficiency and reduces overall costs.

Activated carbon

Activated carbon is frequently used to absorb PFAS. “Fresh” activated carbon has a relatively high separation efficiency for PFAS. However, the efficiency decreases rapidly, allowing PFAS to seep through. A SAFF^® pretreatment can significantly reduce PFAS levels. This means that activated carbon has a significantly longer lifespan and needs to be replaced and regenerated less frequently. This combination significantly reduces the total cost of PFAS removal.

Good to know

SAFF is particularly effective against PFAS compounds with a chain length of ≥C6, achieving 100% removal of PFOS/PFOA and 99% removal of PFHxS in independent tests. The result is a “PFAS super concentrate”, which means significantly less waste needs to be disposed of. (Source: https://epocenviro.com/frequently-asked-questions/)