ANPHOS - Phosphate production from wastewater and digestate
In order to remove phosphate from waste waters or digestate in an environmentally friendly manner the ANPHOS® process can be applied. During anaerobic waste water purification the phosphate present is largely converted into ortho-phosphate, whereas the nitrogen is mainly converted into ammonia (NH4-N). In case of aerobic pre-purification orthophosphate is formed as well with potassium as counter-ion. The principle of the ANPHOS® process is the aeration of waste water, which induces a positive pH shift. As a result of the addition of magnesium(hydr)oxide the ortho-phosphate reacts with ammonia and magnesium ions to form magnesium-ammonium-phosphate (MgAP) or magnesium-potassium-phosphate (MgKP) also known as ‘struvite’. After the reaction the struvite is precipitated, dewatered and dried. This product can directly be applied as substitute for agricultural fertilizers. The ANPHOS® process can be applied on all types of waste waters with P levels of > 50mg/L.