Process & contact
Pyreg (pyrolysis)
Member of DPP
Updated 06/2023
Input materials
Sewage sludge (minimum calorific value 10 MJ/kg, that is around 80% DS). Biomass materials.
Output products
Biochar.
From sewage sludge as input, the product has (as % of DM, and depending on the input sludge characteristics):
- c. 25% (15 - 35%) organic carbon,
- depending on input, e.g. 5 - 7% P content
(of which c. 80% is NAC-soluble),
- just over 1% N
- K: depending on input, < 10%.
Pyreg biochar (from sewage sludge) registered as a fertiliser in Sweden and the Czech Republic. However, sewage sludge biochar is not included in EU Fertilising Products Regulation CMC14.
Process description
Twin screw carbonisation reactor operated at 500 – 800 °C.
Organic hazardous substances of the sludge are destroyed nearly completely, including PFAS.
This temperature results in a biochar with volatile organic carbon content < 1%.
Operating status
Nearly 50 full scale units in operation today, of which 7 using sewage sludge (below: tonnage = input capacity):
- Unkel, Germany (1200 tDS/y, since 2015)
- Homburg, Germany (1200 tDS/y, since 2016)
- Redwood, California (1200 tDS/y, since 2016)
- Hammenhög, Sweden (1200 tDS/y, since 2016)
- Trutnov, Czech Republic (1.200t DS/y, since 2020)
- Lorsbach, Germany (1.500 t DS/y, since 2021)
- Kleve, Germany (1.600 t DS/y, since 2023)
Plus three further plants using sewage sludge under construction in the USA and Asia.