USE OF TEQUILA VINASSES AS CARBON SOURCE AND ELECTRON DONOR FOR BIOLOGICAL NITRATE REMOVAL

摘要

Tequila vinasses represent a pollution problem in Mexico, while nitrate contamination is an environmental problem world-wide. Carbon sources contained in vinasses could serve as electron donors for biological nitrate removal while nitrates are added as electron acceptors. Three different sources of microorganisms were tested for their ability to degrade vinasses, and simultaneously consume nitrate: activated sludge; anaerobic sludge, and soil. Different modes of aeration and vinasse pretreatments were also studied. The anaerobic sludge was the most efficient inoculum; nitrate removal was highest under non-aerated conditions. Highest removal rates of organic matter and nitrate were achieved in thermally pretreated vinasses. Removal efficiency values after 14 days of non-aerated incubation were: COD 59.4%, nitrates 100% (746 mg).