Process & contact
Extraphos Budenheim
This process is no longer under development
Input materials
Digested sewage sludge
Output products
Calcium phosphate - DCP
Process description
1) Liquefied CO2 (standard gas product) is used to partially dissolve phosphorus in liquid sludge to soluble form (ambient temperature, operating pressure c. 10 bars).
2) solid/liquid separation
3) the liquid fraction is used for P-recovery, by pressure release and some lime addition, resulting in calcium phosphate precipitation
Iron, aluminium, heavy metals and organic carbon remain mainly in the solid fraction. Tests of contaminant removal using acid acidulation are underway.
Operating status
Process initially developed by Budenheim with a mobile pilot plant: 1 m3 volume.
Technology now owned by Remondis