A COST-EFFECTIVE SORBENT FOR DECOLOURISATION OF TREATED SPENT-WASH

摘要

For decolourization of spent-wash modern techniques like membrane filtration, wet oxidation and electrochemical oxidation are in vogue. They have their own limitations due to high cost of investment and operation. Since colour removal of spent-wash is and END-OF-PIPE treatment step, its cost effectiveness dictates the commercial application. Presently popular biomethanation of spent-wash gives valuable biogas degrading the COD and BOD values effectively. Next step, which is either activated sludge process or physico-chemical process removes colour to a certain extent. Finally, the secondary treated spent-wash has to undergo decolourization using active charcoal. If the costly active charcoal can be replaced by cheap sorbents, the process can become customer-friendly. In the present study, we have prepared a cheap sorbent using solid sludge from effluent treatment plant (ETP) attached to a distillery. Using calcium chloride as a chemical activating agent, an active sorbent was prepared. Eventhough it contained less than 12 % carbon, the capacity of this active sorbent was quite high for colour removal of treated spent-wash. High yield, low cost of preparation and fairly high capacity qualifies this novel sorbentfor industrial applications involving colour removaljobs.