Enhancing synthetic vinasse treatment efficiency using an integrated UASB-Modified Bardenpho Process

Vinasse poses considerable environmental problems due to its complex composition of organic matter, minerals, and toxic compounds. If discharged into the environment without treatment, it can cause adverse impacts on ecosystems. This research investigated the effectiveness of an integrated treatment system involving an upflow anaerobic sludge blanket (UASB) reactor and the modified Bardenpho process (MBP) for purifying synthetic vinasse. The study lasted for 167 days, during which the integrated UASB-MBP system processed untreated synthetic vinasse with organic loading rates (OLR) ranging from 1.6 to 12.5 kgCOD/m³ day. The UASB-MBP system impressively achieved a COD removal efficiency of 99.41%. Removal efficiencies of approximately 98.14, 99.91, and 99.63% were also achieved for total nitrogen (TN), total phosphorus (TP) and total ammonium (NH₄⁺-N), respectively. The final discharge was 51.06 mg/L. The concentrations of NH₄⁺-N and TN in the outflow of the settlement tank were 0.8-1.2 mg/L and 5.1-7.9 mg/L, respectively. Optimal performance was achieved when the HRT and nitrate recycle ratio were 15.5 h and 200%, respectively. The temperature was kept in the mesophilic range (33-35 °C) during the experiments. These results underscores the potential of the integrated UASB reactor and modified Bardenpho process to provide an effective and eco-friendly approach for concurrent removal of COD and nutrients from vinasse treatment, offering broad prospects for implementation in wastewater treatment.