Cassava Mill Wastewater Treatment by a Combination of Physical and Nature-Based Processes : A Pilot Study

Abstract

The absence of wastewater treatment facilities in small-scale cassava agroindustry results in the disposal of toxic effluent that causes environmental problems to host communities. A pilot multi-compartment reactor packed with graded earthen materials with continuous aeration and anaerobic degradation was evaluated for the treatment of cassava mill wastewater. The results suggest that continuous aeration and biodegradation of the effluent reduced Hydrogen Cyanide by 84%, BOD (72%), COD (69%) and Turbidity (41%). A slightly acidic pH of 5.0 was obtained for the final effluent. The results suggest an efficient and promising technique that combines physical and nature-based processes in degrading key pollutants from cassava effluent. Despite having some pollutants with final values above permissible limits, the system can be optimized to enhance performance. The treatment technique is adjudged sustainable with low technical operating demands and can be used for on-site wastewater treatment in small and medium scale cassava processing clusters.