Performance of Wastewater Stabilization Ponds: A Case Study of Nzoia Sugar Factory Wastewater Treatment Plant, Kenya

Abstract

- Water pollution is one of the most common environmental problems encountered worldwide, especially in developing nations. To avert this, both domestic and industrial effluents should be treated by appropriate technologies to acceptable levels before disposal. Wastewater stabilization ponds are widely used for domestic and industrial wastewater treatment worldwide. This study aimed to determine the performance of wastewater stabilization ponds for industrial sugar effluent by evaluating the treatment plant's operational parameters and hydraulic characteristics. Key parameters were; biochemical oxygen demand, total suspended solids, chemical oxygen demand, total dissolved solids, and electrical conductivity. Wastewater samples were tested using the standard testing methods. The results showed the treatment plant did not meet the acceptable discharge standards for the key parameters. It was also established that all parameters varied significantly (p˂0.05) across the different ponds except for BOD (p>0.05). Wrong positioning of the inlet and outlet structures, a smaller length to width ratio, and non-functional mechanical aerators were attributed to the poor effluent quality. Recommendations were to address the design aspects of the ponds and ensure proper maintenance of the mechanical aerators