Electro living membrane bioreactor for efficient and sustainable treatment of textile wastewater and enhanced fouling control

The effects of integrating electrochemical processes into the innovative living membrane bioreactors (LMBR) for treating synthetic textile wastewater were examined in this study. The efficacy of electrochemical-enhanced-LMBR (e-LMBR) was assessed using wastewater containing high COD levels (1000 mg/L) and reactive (25 mg/L) and direct (25 mg/L) dyes as pollutants. The performance of the e-LMBR was compared with that of the LMBR, which had previously demonstrated high COD and DOC removal efficiencies. Both experimental configurations achieved similarly high removal efficiencies higher than 96 %. Noteworthy, the e-LMBR exhibited a removal efficiency of humic substances of 75 ± 17 %: an average value of 25 % higher than that for LMBR. Notably, the electrochemical processes substantially improved the pollutant removals: the e-LMBR demonstrated higher reductions in sulfate, nitrate‑nitrogen (NO 3 − -N), and phosphate-phosphorous (PO 4 3− -P) concentrations than the corresponding LMBR. Average ammonia, phosphates, and sulphates removal efficiencies were 99 ± 1 %, 86 ± 3 % and 55 ± 8 %, respectively, for the e-LMBR. Besides, the direct and reactive dye concentrations in the e-LMBR effluents were approximately reduced to 2.9 ± 0.5 mg/L and 2.1 ± 1.7 mg/L, corresponding to removal efficiencies of 87.5 ± 5.1 % and 91.4 ± 4.4 %, respectively. Finally, e-LMBR showed a 77 % lower membrane fouling rate and lower concentrations of fouling substances in the reactor compared to the LMBR. Incorporating electrochemical processes into a living membrane bioreactor presents a cost-effective and highly efficient solution for treating textile wastewater. • COD and DOC reduction efficiencies higher than 96 %. • Humic acid-like compounds removal efficiency of 75 ± 17 %. • Average ammonia, phosphates, sulphates removal efficiencies of 99 ± 1 %, 86 ± 3 % and 55 ± 8 %, respectively. • Direct and reactive dye removals of 91.5 ± 2.9 % and 88.1 ± 7.4 %, respectively. • Highly efficient fouling mitigation achieved by reduced concentrations of fouling precursors.