Wine distillery wastewater degradation. 1. Oxidative treatment using ozone and its effect on the wastewater biodegradability.

Laboratory-scale experiments were conducted to investigate the impact of ozonation on the degradability of wine distillery wastewaters, usually called vinasses, with the goal of developing combined chemical-biological methods for their treatment. Chemical oxygen demand (COD), biological oxygen demand (BOD), total organic carbon (TOC), and ultraviolet absorbance at 254 nm (UV(254)) were taken as reference parameters to follow the pollution level. The vinasses were treated both directly and after being mixed with domestic sewage. Ozonation of pure vinasses required high ozone doses to achieve a significant efficiency for removing the organic matter. Mixing vinasses with domestic sewage allowed higher degradation rates with ozone. Ozone was also demonstrated to be an appropriate oxidizing agent to improve vinasses's biodegradability and organic matter removal. A mathematical model of the ozonation kinetics based on the film theory concept is also presented.