Application of anoxic fixed film and aerobic CSTR bioreactorin treatment of nanofiltration concentrate of real textile wastewater

摘要

An anoxic fixed film bioreactor (FFB) with biomass immobilized on activated carbon and anaerobic continuous stirred tank bioreactor with overflow were applied to degrade concentrate fromnanofiltration of real textile effluents containing Reactive Red 120 (RR-120). The efficiency ofcolor removal was 99 % irrespective of the fraction of nanofiltration concentrate in the feed. Anapproximate dye balance based on the assessed adsorption capacity of RR-120 by activated carbonindicated that the dye was removed by means of adsorption as well as of biological processes.Aromatic amine released from a dye molecule was fully adsorbed by activated carbon. COD levelin the outflow of the system was above that imposed by legislation. Despite an adjustment of thefeed pH to 7 this was constantly increasing up to the value above 9 in both reactors. Neither thenanofiltration concentrate nor the effluents from the bioreactors affected the growth of Pseudomonasputida used as toxicity indicator.