ABSTRACT
Phosphorus (P) scarcity, jointly with eutrophication problems and water shortage, are forcing urban wastewater treatment plants (WWTP) to redirect their focus to nutrient recovery and treated water reuse. However, before implementing any recovery approach, it is necessary to understand the problem and its variability. In this scope, this work aims to collect data from different WWTP to assess P concentrations, speciation, and variability in urban wastewater. The analysis revealed high levels of total P, before and after anaerobic digestion, and in the sludge dewatering water (100-400 mg P/L), with about 60-80% of total P in the soluble form. Also, in the best-case scenario, soluble reactive P (orthophosphate) accounts for over 50% of soluble total P. Preliminary results showed that it would be possible to recover over 100 kg P/day in a WWTP with about 160,000 p.e.
