International Journal of ChemTech Research CODEN( USA): IJCRGG ISSN : 0974-4290 Vol.5, No.2, pp 707-711, April-June 2013 ICGSEE-2013[14 th – 16 th March 2013] International Conference on Global Scenario in Environment and Energy Electrochemical Process For Removal Of Color From Effluent Of Maize Based Starch Processing Unit Bidyut Mazumdar, Abhinesh Kumar Prajapati, Parmesh Kumar Chaudhari* Department of Chemical Engineering, National Institute of Technology, Raipur-492001, Chhattisgarh, India *Corres.author: pkchaudhari.che@nitrr.ac.in, Phone: +91-94061 45088, Fax: +91-771-2254600 Abstract: Electrochemical (EC) process for color removal of biodigester effluent of maize (corn) based starch industry wastewater (BDE-MSIWW) was investigated in a 1.5 dm 3 electrolytic batch reactor using aluminum as a sacrificial electrode. Experiments were conducted by the varying pH (4-10) and current density (CD) 51-255 A/m 2 (1-5 A) at 2.2 cm electrode gap. The color reduction of 97 %, 98 %, 67 %, 68 % and 44 % obtained at pH 4, 5, 7.8, 9 and 10 respectively. The color reduction also increased with current density. The best settling of slurry obtained at pH 9 and poorest at pH 4. Keywords: Starch industry wastewater, Biodigester effluent, Electrochemical process. 1. Introduction Maize (corn) is the major raw material for producing products like glucose and starch, which is a major ingredient in human diet. In integrated maize based starch industry each part of maize produces various valuable products like starch, glucose, maize oil, cattle and poultry fodder. For per ton of maize used in starch production about 8 m 3 water is consumed which generating 5.5 m 3 of waste water 1 . This wastewater has high organic load. Therefore, treatment of wastewater is required. In the most of industries in India, composite effluent from integrated starch industry (pH 5-6) is not taken directly for anaerobic digestion treatment, but it is mixed with some effluent of bio- methanation reactor (pH 7.5-8). It is done to maintain optimum (pH~7) of the wastewater stream suitable for biomethanation process, which is sent back to bio-methanation (bio-digestion) reactor. The treated effluent from anaerobic biodigester is called biodigester effluent (BDE), which is fed to aerobic lagoon for bio-aerobic treatment. The discharge of aerobic lagoon contains COD 800-1200 which does not meet the discharge water quality standards to release into surface water (COD < 100 mg/dm 3 ) and sewers (COD < 300 mg/dm 3 ) applicable in India 2 . The black color of effluents is harmful for aquatic life because it reduces air diffusion and sunlight absorption, consequently hindered the photochemical reactions for self purification of the