PHOSPAQ^™

PHOSPAQ^™ combines the removal of COD with the removal and recovery of nutrients like ammonium and phosphate. PHOSPAQ^™ removes up to 95% of the phosphate in wastewater. PHOSPAQ^™ as been applied or treatment of municipal sidestream reject waters as well as in industrial wastewaters increased.

PHOSPAQ^™ is feasible from approximately:

• Load: > 100 kg P/d.
• > 50 mg/l PO4-P
• > 200 mg/l NH4-N

The PHOSPAQ^™ process removes biologically degradable COD, phosphate (PO₄^3-) and ammonium (NH₄⁺) from wastewater. PHOSPAQ^™ is often implemented to increase the phosphorous removal to meet stringent discharge limits. It also prevents downstream struvite scaling of piping and equipment saving maintenance cost.

As phosphate is a finite resource essentially for all life, phosphorus recovery from wastewater has become paramount. PHOSPAQ^™ allows facilities to harvest phosphate in the form of magnesium ammonium phosphate (struvite) which can be turned into a slow release fertilizer or used as feedstock for other products like fire retardants. PHOSPAQ^™ is a cost-effective and environmentally friendly technology for phosphorus recovery.

The PHOSPAQ^™ process takes place in an aerated reactor. Aeration provides optimal mixing of the struvite particles, simultaneously supplying oxygen for the biological conversion of COD. Stripping of carbon dioxide increases the pH and promoting struvite precipitation.

Magnesium oxide is added to remove phosphate that is recovered by precipitation as magnesium-ammonium-phosphate (struvite). The PHOSPAQ^™ reactor is equipped with separators that retain the struvite and discharges the purified effluent.

The struvite is harvested from the bottom of the reactor and can, depending on the outlet requirements, be further processed, purified and dewatered.