Treatment of waste water from distilleries with chitosan

Purification of vinasse-containing water by an anion-exchange process has been described. The biopolymer chitosan has been used as anion-exchanger, Model experiments with different amounts of Chitosan and different time of contact between the substrate and the waste water have shown a chitosan concentration of 10 g l(-1) and a contact time of 30 min to be the most suitable for the purification of the model waste water with a chemical oxygen demand (COD) of 2800 mg O-2 l(-1). A laboratory column process of water purification has been realized on the basis of these parameters. The possibility of subsequent biomethanation of adsorbed organic acid anions on the ion exchanger by a direct adding of chitosan to an anaerobic bioreactor before and after preliminary hydrolysis has been demonstrated. (C) 2000 Elsevier Science Ltd. All rights reserved.