Biosolids have traces of many contaminants, including PFAS, that must be remediated.
- Pharmaceutical products, micro-plastics, hormones, cleaners, oils, fats, greases, VOCs and many other contaminants that make their way into sewage.
- These contaminants make it through the drying stage of our competitors and are present in all dried biosolids products that are currently sold and distributed nation-wide (i.e., Milorganite).
- In the SBS process, these contaminants are separated from the solids in the pyrolysis stage.
- Once in a gaseous form these contaminants are quickly destroyed by thermal oxidation.
Pyrolysis is a decontamination technology that works extremely well with biosolids.
- Dried biosolids are heated in an oxygen-free environment at over 1,100°F for up to 30 minutes which causes even the toughest contaminants to separate and become part of the syngas.
- Syngas is kept hot for the several seconds of its existence to ensure molecules don’t start reconnecting and forming air emissions.
- PFAS compounds are liberated from solids into a volatile gas state where they are destroyed by thermal oxidation (>1,600°F).
- Syngas is thermally oxidized in stages to achieve the lowest NOx emissions possible.
Pyrolysis has been similarly used to remediate soil contaminants for decades, albeit without the advanced air treatment solution that we employ.