ABSTRACT
Distillery and sugar mill wastewater is characterized with a strong color, high BOD and COD and the presence of many colored organic compounds. It contains melanoidinds, complex and colored organic compounds formed during the distillery and sugar processing; have resistance to the microbial decomposition. Further presence of lignins and tannins in the distillery and sugar mill wastewater makes the treatment very difficult especially the removal of color. The conventional treatment mainly includes physicochemical processes i.e. floatation, sedimentation, coagulation and flocculation; biological processes i.e., aerobic and anaerobic digestion that are primarily effective in removal of suspended solids and biodegradable organic matter. Many advanced processes like filtration, adsorption and oxidation are also used for the effective removal of color and dissolved solids; but high costs of building and operation and the need of skilled personnel makes them unaffordable and unviable for the industries.
Microalgal remediation could be a potential and sustainable approach that not only provide the effective treatment but also helps in reduction of the cost of the treatment. Due to minimal growth requirements and their wide range survivability, it could be more adaptable in the removal of lignin, tannins and melanoidins from the distillery and sugar mill wastewater. Microalgae also reported the presence of laccases (LACs) and polyphenol oxidases (PPOs) enzymes, that known for their role in the lignin, tannins and melanoidins degradation.
This chapter provides a brief account of the distillery and sugar mill industry, wastewater from these industries and their composition, specific pollutants and impacts on the environment and on public health. It also gives the information on current treatment and their challenges and how microalgal remediation could be able to provide effective and affordable treatment for the distillery and sugar mill wastewater.
