Leachate and vinasse used in a biological process combined with Fenton’s reaction: a green method for treatment of textile effluents

Abstract: The production of textiles generates a large amount of liquid residues considered to be environmentally problematic and which, if discarded without due treatment, may cause eutrophication of water sources, the intoxication of living beings, and the blocking of light penetration. Some methods have been applied for the treatment of this type of waste, with the prominence of biological and physicochemical techniques. The combination of two or more techniques enhances the treatment’s efficiency. This work investigated the use of bacteria derived from the leachate produced by the textile industry itself, fed with vinasse, a by-product of the alcohol industry, with subsequent application of Fenton’s reaction. The biological method, optimized in terms of aeration and quantity of nutrients for the bacteria, combined with the physicochemical method optimized in terms of the amount of reagents, was efficient for the discoloration of the effluent in approximately 100 %, for toxicity reduction, for the degradation of organic matter in 80 %, and with acceptable acidity for disposal after only eight days of treatment. The method was considered of great efficiency and low application cost, without the production of hazardous waste.