Treatment of Iron Rich Groundwater Using KMnO4 and a Fixed Bed of Animal Bone Char

Abstract

The chemical composition of groundwater samples in Yenagoa, Bayelsa State of Nigeria was experimentally investigated. Parameters as pH, temperature, redox potential, iron oxidizing bacteria, dissolved oxygen, iron and manganese were analysed. Results indicate the groundwater samples are rich in iron (3.28mg/L) above regulatory limits of 0.3mg/L. A treatment process was developed to improve the quality of the groundwater. The treatment process involves pre-treatment of the effluent with varying concentrations of KMnO4(1.5mg/L, 2.0mg/L and 2.5mg/L), and passed through a fixed-bed of bone char. The treatment process involving the use of 2.5mg/L dose of KMnO4 filtered through a fixed bed of bone char treatment showed iron and manganese reduction from 3.28mg/L to nil and from 1.03mg/L to nil representing 100% reduction for both metals. Iron oxidizing bacteria (IOB) was reduced from 106 cfu/ml to 101cfu/ml reduction representing 99.999% reduction. Values of pH, temperature, dissolved oxygen (DO) and redox potential were also affected. Results showed a good compliance with World Health Organisation (WHO) standards for drinking water. This means that the final effluent obtained is safe for human consumption and poses no aesthetic nuisance.