REMOVAL OF IRON FROM GROUNDWATER BY CASCADE AERATION: THE CASE OF BASKETO SPECIAL WORE

Abstract

Water is crucial not only for sustaining life but also for socio-economic development of a country. However, its availability in the right quality remains a great challenge. A high concentration of iron in groundwater is a serious problem in Basketo Special Woreda, because of iron contamination in groundwater that is often greater than established limits for human health of 0.3mg/l as the WHO recommendations, which gives the water a sour metal taste, stains laundry and food cooked in the water receives an unappetizing color. As a result, people use the iron water and unprotected surface water instead hence the need for removal of the iron. People are at risk of being exposed to iron contaminated groundwater especially areas, as those communities use groundwater for drinking water and household tasks. To overcome the aforementioned problem, this study shows treating the groundwater with cascade aeration. In which three cascade setups are constructed to prepare a possible treatment unit and select optimum removal efficiency of iron between cascade setups. The raw water sample was collected from Basketo Special Woreda and tested at Arba Minch University Water Quality Engineering Laboratory in order to establish the concentration of iron and to prepare a synthetic representative solution. The ferrous iron (Fe+2) stock solutions were prepared from Ferrous Sulfate Heptahydrate (FeSO4.7H2O) by using distilled water. The result showed that the initial iron concentration in the sample water was found to be 4 mg/l and the final concentration of iron after cascade aeration was 3.27 mg/l, 2.85 mg/l and 2.53 mg/l with a removal efficiency of 25.22% ± 3.58, 43.56% ± 1.40, and 63.02% ± 2.09 for cascade setup 1, 2, and 3 respectively.