High-efficiency removal of phosphorous from filtered activated sludge effluent using electrochemical process

Abstract Recently electrochemical process for removing phosphorous (P) from effluents has received more attention to control water resource pollution. However, there are many uncertainties about energy demand in this process. So, in this research energy demand was principally investigated. P concentration was measured on 210 samples before and after the electrochemical process. Direct current electricity was applied in the range of 0.1–1.5 A (A). Cathode and anode electrodes were eight pieces of steel plate submerged in the liquid. After measurement of P concentration, the data were analyzed by Greenhouse-Geisser, one-way ANOVA and Tukey's tests. The results showed that the optimum reaction time and electricity currents were 10 min and 0.6 A, respectively. Also, 98% efficiency for P removal was achieved. The current density was 1.89 mA/cm2. The energy demand was 7.69 KWh per equivalent of removed P and 0.45 kWh/m3. The data showed that the proposed method is economical and certainly more efficient in comparison with conventional P removal methods. Therefore, the electrochemical process alone by steel electrodes may be a capable process for P removal from filtered activated sludge effluent.