Distilleries wastewater is an important environmental problem due to its high BOD and COD content, and toxic materials such as phenolic compounds, and low pH. Direct and continuous discharge of this effluent to the soil reduces the quality of soil and destroys agricultural crops. In addition, its discharge to rivers and sea will seriously affect aquatic life. In order to prevent environmental hazards, a number of biological, chemical and physical methods have been introduced for treatment of this wastewater. Chemical and physical methods are based on surface sorption, ion exchange, membrane processes and chemical oxidations. In biological methods, anaerobic processes are more economical than aerobic processes and are more developed more in recent years. Anaerobic lagoons reduce 60-70% of BOD with 1-2 months retention time. Most of anaerobic bioreactor methods are able to reduce wastewater BOD by 80-85% and the remaining 15-20% of BOD can be reduced by aerobic processes.
)