Influence of excess nitrogen in the treatment of the textile effluent in sequential batch reactors with Aspergillus nigerAN 400

ABSTRACT

Textile wastewater was treated by Aspergillus niger AN 400 in sequential batch reactor, which was operated in cycles of 48 h in order to evaluate the effect of an additional source of nitrogen on the system's efficiency, which was fed with effluent diluted (10% v/v) and glucose (3 g.L^-1). The influent received addition of an external source of nitrogen (phase I), in which there was excess ammonia (192 mg.L^-1) in the medium, resulting in organic matter removal of 85%, but in only 55% removal of dye. In the phase II, when the average concentration of ammonia in the medium was lower (98 mg.L^-1), removal of dye (83%) became higher than that of organic matter (69%), showing the negative effect of high concentrations of ammonia over the system and favoring the growth of bacteria, which probably inhibit the production of fungal enzymes and contributed to the loss of efficiency in the removal of dye and the formation of byproducts.

Keywords:
Carmim Indigo; sequential batch; textile effluent; fungi.