A batch monopolar reactor was developed for total phosphorus (TP) recovery using electrochemical struvite precipitation. This study involves the optimization of factors using response surface methodology to maximize the TP recovery. The optimal parameters for this study were found to be a pH of 8.40, a retention time of 35 min, a current density of 300 A/m2, and an interelectrode distance of 0.5 cm, resulting in 97.3% of TP recovery and energy consumption of 2.35 kWh/m3. A kinetic study for TP removal revealed that at optimum operating conditions, TP removal follows second‐order kinetics (removal rate constant(K) = 0.0117 mg/(m2·min)). The system performance was compared to the performance of an iron electrocoagulation system. The composition of the precipitate obtained during the optimal runs were analyzed using X‐ray diffraction and EDS analysis. X‐ray diffraction analysis of the magnesium precipitate revealed the presence of struvite as the only crystalline compound. Practitioner Points Electrochemical struvite precipitation has the potential to recover total phosphorus from anaerobic bioreactor effluent. Optimum conditions for phosphorus recovery was found at a pH of 8.4, retention time of 35 min, current density of 300 A/m2, and interelectrode distance of 0.5 cm. The quadratic model predicted complete (100 %) TP recovery under optimized conditions, whereas 97.3 % recovery was observed under experimental conditions. TP removal under optimum conditions followed second‐order rate equation (removal rate constant(K) = 0.0117 mg/(m2·min)). XRD analysis of the precipitate revealed struvite as the only crystalline compound.

A batch monopolar electrocoagulation system was developed and studied for the removal of phosphorus from anaerobic bioreactor effluent using iron as an electrode material. The study focused on the optimization of the independent variables, such as initial pH, retention time (RT), current density (CD) and inter-electrode distance (IED) using the response surface methodology (RSM) to maximize the removal of total phosphorus (TP). A quadratic model was fitted to the experimental data for TP removal. The optimal parameters were found to be pH of 6.75, RT of 11.06 min, CD of 300 A/m2, and inter-electrode distance of 1.5 cm resulting in 98.05% TP removal and energy consumption of 1.28 kWh/m3. A kinetic study for TP removal revealed that at optimal conditions, removal followed first-order kinetics (K = 0.185 m/min). Phosphorus was recovered from the post-precipitated sludge through combustion at 900 °C followed by acid leaching with sulfuric acid. Acid leaching tests were carried out with sulfuric acid for the post-precipitated sludge obtained at the optimum conditions. It resulted in around 91% of phosphorus recovery at a liquid-to-solid ratio of 100 mL/g.