Design of a small scale iron and manganese removal system for Copperbelt University’s borehole water

 The study aimed at designing and performance testing of a suitable small scale Iron and Manganese removal system for Copperbelt University’s Borehole water. Materials for the filtration system were locally sourced within the Copperbelt province of Zambia. Tests were carried out on borehole water and system filtered water. The results show that the system performed relatively well on reducing Iron and Manganese from groundwater. The model constructed was a small scale version of an Up-flow filtration system. Evaluation showed performance efficiencies of 81.67% and 32% on iron and manganese removal respectively. The Up-flow design is better because water takes relatively more time to pass through the filter increasing contaminant removal capacity. The aerator tray was good but retention time for air was not sufficient and could be made better. Based on the results from the lab scale model a full scale Prototype was proposed and designed. Selecting the most applicable design largely depends on economical availability of materials, ease of construction and operation all this in relation to system efficiency. The Up-flow design in this study can be improved with respect to (i) the sedimentation tank for the settlement of oxidized iron and manganese by improving retention time of water (ii) spray nozzle to increase the surface area for aeration of water. Additionally, a substitute aerator tray with cascades to increase retention time for aeration is proposed. Furthermore, based on the model and literature review of similar designs, the sand layer depth should be at least 20 cm.