Wine distillery wastewater degradation. 2. Improvement of aerobic biodegradation by means of an integrated chemical (Ozone)-biological treatment.

Biological degradation of vinasses, generated during alcohol production from wines and pressed grapes, has been studied in four digesters operating in fill and draw mode. Digesters 1 and 2 were fed with nonozonated and ozonated mixtures of vinasses and domestic sewage (1:10 by volume), respectively. Digesters 3 and 4 operated with pure vinasses at acid and neutral pH values, respectively. The effects of pH, temperature, and ozone dose conditions were studied. Preozonation removed inhibitory compounds and improved the growth of nitrifiers. Ozone dose is the key variable to treat a vinasse-domestic sewage effluent effectively with a combined chemical-biological system. Contois's kinetic model has been applied to experimental results, and kinetic parameters related to the maximum specific growth rate of microorganisms, mu(max), and inhibitory effects, alpha, were calculated and compared for nonozonated and ozonated wastewaters.