Possibilities of using ozone for the treatment of wastewater from the yeast industry

The purpose of the study was to establish if ozonation can be used to enhance the process of purifying wastewater from the yeast industry. The results of the experiments indicate that ozonation can be used in the tertiary treatment of yeast wastewater for the reduction of colour, odour, and the overall concentration of contaminants. During ozonation, the biodegradability of the wastewater increased; therefore it is possible to include ozonation into the combined purification process simultaneously with anaerobic and aerobic bio-oxidation. In addition, the application of ozonation as a pre-treatment method for anaerobic digestion of excess sludge from wastewater treatment plants was studied. Ozonation of the excess sludge resulted in a reduction of the sludge amount and increased the solubility of sludge organic matter. Although the solubility of sludge increased, the process of anaerobic mesophilic digestion was not improved.