Distillery industries in India pose a very serious threat to the environment because of the large volume of wastewater they generate which contains significant amount of recalcitrant compounds. Distillery spent wash has very high COD and BOD with low pH and dark brown color.
Here membrane technology has answer. This spent liquor after distillation column to be treated by first Ultra filtration membrane followed by Nano filtration membrane and recycle fresh water again for fermentation plant.
In India there are major wine and beer producers has setup their plants in Utter Pradesh, Maharashtra, Tamilnadu, Madhya Pradesh etc they are producing alcohol by using Molasses as raw material. This molasses contains 7 to 8% glucose which is converted in to alcohol by fermentation process. First molasses is diluted to by adding water and adjust the total dissolved solids up to 7 to 8%. Then Yeast to be added in diluted molasses solution and fermentation takes place. As process go up glucose is converted in to ethyl alcohol and carbon dioxide. This carbon dioxide will free as a gaseous form which either collected separately. After sufficient conversion from glucose in to ethyl alcohol this solution now called beer solution. This beer solution then passed through distillation column. Based on temperature difference ethyl alcohol separated from beer solution and condensed in to liquid form. After distillation column spent liquor contains lot of dissolved impurities mainly organic, color, TDS, oil and suspended solids which is very difficult to treat by regular effluent treatment plant.