Indaver wants to remove Substances of Very High Concern (SVHCs), such as PFAS, from wastewater on a large scale. Substances of Very High Concern are chemicals that are dangerous to humans or the environment because, for example, they are carcinogenic, disrupts reproduction or accumulates in the food chain. The criteria used to identify a substance of very high concern are set out in the REACH regulation.
To remove those SVHCs, Indaver installed a reverse osmosis pilot plant at its Waste Transfer Station in Terneuzen, as an addition to its current wastewater treatment plant. This pilot installation proved in 2022 that it is indeed possible to extract the substances of very high concern from the water.
To remove the contaminants, Indaver uses the reverse osmosis technique. This means that we press water through very small holes under high pressure, causing the water to pass through and the pollution, such as, for example, PFAS, to remain behind.
PFAS, a collective name for chemicals (poly- and perfluoroalkyl substances) that do not naturally occur in the environment, is one such example of a ZZS.
The pilot plant, which has been running in Terneuzen since February 2022, has shown that reverse osmosis works. For most PFAS chains, we achieve 100 per cent efficiency. A few smaller molecules still require post-treatment but even these can then be removed from the water.
In the treatment plant, Indaver makes a concentrate of pollution. That means we are left with clear, clean water on one side and a concentrate of all the contaminants still present in the water, including PFAS.
Almost all the water, 95 per cent to be precise, pumped through the plant can be safely discharged into the Western Scheldt. The remaining five per cent, the concentrate, has yet to be processed. This is done at Indavers' specialised and licensed facilities in Antwerp.
Depending on the composition of the water, reverse osmosis may or may not be a solution. Too many salt components in the water, for instance, would clog the holes in the installation. Scale also plays a role.
The pilot plant proved its worth and so Indaver decided to scale up its reverse osmosis plant so that we can treat all the wastewater from our Terneuzen site from Q2 2023.
With this plant, Indaver prevents PFAS from entering surface water from Indaver. Moreover, Indaver also avoids CO emissions with this because instead of twenty, only one truck with wastewater needs to drive to Antwerp every fortnight.