High-performance modified sbr for simultaneous removal of organic and nitrogen matters from rubber latex processing wastewater

Abstract

In this study, the simultaneous removal of organic and nitrogen substances from rubber latex processing wastewater was investigated using modified sequencing batch reactors (SBRs). The reactors were specially designed to consist of both oxic zone with aeration and anoxic one without aeration in a single-stage reactor. In these reactors, wastewater mixture is able to continuously circulate itself from one zone to the other during aeration. Therefore, nitrification and denitrification could be occurred simultaneously in the two zones of these reactors. Reactors R1 and R2 with different aeration modes were used for evaluating the effect of aeration modes. Aeration was kept at constant air flow-rate for R1, while varried from lower air flowrate in the early period of the reaction stage to higher air flow-rate in the later one for R2. The reactor R1 with the conventional aeration mode achieved high COD as well as T-N removal efficiencies. Furthermore, the performance of the reactor R2, which was operated under the specific aeration mode, was greatly improved in terms of T-N removal. In the ranges of COD and T-N loading rates of 0.9-1.6 kg COD⋅m^-3⋅d-1 and 0.16-0.31 kg N⋅m^-3⋅d-1, respectively, the average COD, ammonium, and T-N removal efficiencies of R2 were 97%, nearly 100%, and 94-97%, respectively.