After a call-out and returning to the station, hoses and equipment must be washed and uniforms wash and re-imprinted before the next call-out.
The washing water can then contain all kinds of pollution’s ranging from un-burned fuels, soot, heavy metals and a cocktail of organic residues including Pfas. Analysis levels of Pfas 11 could bee around 300ng/l.
This water then goes to the municipality’s sewage treatment plant and in the worst case can interfere with the treatment but also contaminate the sludge and most of the PFAS goes on uncleaned.
Cleaning at the source would be preferable. A simple method we now are testing is to filter the washing water through a Laqua Filter at the fire station.
Since November, a pilot has purified a partial flow of the washing water before it went to the waste water network
Bio-char and peat appear to be as effective as activated carbon, where the peat functions as an ion exchang but also initiates a biological breakdown of the organic pollutants
A first analysis of the cleaning ability will come soon. Other trials with biochar have shown reductions in Pfos of 90% and Pfas 11 of 82% in the line of activated carbon. Bio-char are a cheaper and more environmental chose comparing with activated carbon.
Laqua Treatment AB 