Removal of iron from water using oxidation process

• Main Author: Lim, Li Pin
• Format: Final Year Project / Dissertation / Thesis
• Published: 2021
• Subjects: TP Chemical technology
• Online Access: http://eprints.utar.edu.my/5372/2/1603590_FYP.pdf; http://eprints.utar.edu.my/5372/

Ferrous iron is found naturally in groundwater. According to World Health Organisation (WHO), the maximum allowable concentration of iron in drinking water is 0.3 mg/L. However, groundwater in Malaysia especially Kelantan has elevated iron level. Groundwater with high iron content is not suitable to be consumed due to bad odour, unpleasant taste and the possibility of pipe clogging. Continuous intake of iron rich water can lead to health issue. Various technologies have been developed worldwide for remediation of iron contaminated groundwater. This work provides a review on the oxidation approach used to remove iron from groundwater, with emphasis on different types of oxidants (air, ozone, potassium permanganate (KMnO4), sodium hypochlorite (NaOCl)) and effects of operating parameters (dosage of oxidant, pH of water, retention time). It was found that KMnO4 has the highest iron removal efficiency up to 100 %. In addition, the evaluation indicates that the increase oxidant dosage to above stoichiometric amount can increase the iron removal efficiency. Next, it was discovered that oxidation of iron by air, ozone, NaOCl, KMnO4 occur optimally in slightly alkaline condition. A retention time ranging from 5 to 30 minutes are sufficient to achieve desired iron removal efficiency. Other than conventional oxidation process, the recent improvement oxidation technologies (subterranean iron removal, Vyredox method) and catalytic filter materials (DMI-65, Birm, Pyrolox) to improve the conventional oxidation process for iron removal from groundwater were also evaluated. Lastly, a case study on the groundwater in Tanjung Mas, Kelantan was carried out in an attempt to identify the suitable oxidant to be used for iron removal. Thus, this study confirmed that oxidation process is applicable for iron removal in groundwater Malaysia.