Presenting our just completed 60 m3/h treatment system for PFAS and particle removal from tunnel construction waste water.

Last week ended with Victor Steffansson handing over the ”key” and manuals to construction company YIT – for the complete water treatment system installed to treat water from construction works for Högdalen depo worktunnel 5712.


Water are pumped straight from the drilling rigs carrying out the tunnel construction works, to the treatment plant. As the water enters the first treatment step, a two step mixer, flocculation and precipitation chemicals are automatically added proportional to the flow rate, as well as CO2 for #pH adjustment. The particles are then given enough settling time in two lamella separators connected in parallel. The treated water then enters a buffer tank where the water is pumped to the next step of 4 pressurised filter vessels containing glass media for polishing of the last particles. As the water is about to enter the filter step, turbidity and #conductivity is measured and logged.
From here the water is pumped to another buffer tank where the water can be recirculated back to the drilling rigs, or released to the recipient. Or to a next treatment step, if works are carried out in a tunnel section where PFAS can be expected. 


As the tunnel is situated underneath a landfill, some of the water is expected to be containing PFAS as leachate can reach the tunnel during the works. In this case the water from the polishing step is directed to 4 filter vessels in series containing activated carbon, ready ro treat the PFAS. And then also PFAS contaminated water can be reused or discarded.
And all packaged in a neat, slim, modular based treatment system with minimal footprint, in a weather proof protection tent. A system designed by Envytech in close cooperation with our partners Cornelsen Ltd. UK.

Now THAT is what awesome looks like in our book 👌🤩👏
For information about the project, contact project manager and lead designer Victor Steffansson