Measurement of dissolved oxygen in the cascade aerator for groundwater treatment at Rumah Nur Kasih Ulu Sepetang, Perak

Abstract

A tube well 15 meter deep and 150 mm diameter had been constructed as alternative water supply at Rumah Nur Kasih to help minimize operating cost for orphanage home by water cluster Universiti Sains Malaysia (USM). However, the groundwater wills changed color to rusty after oxidizes with oxygen, unpleasant taste and appearances due to high concentration of iron (Fe3+) and manganese (Mn4+). This groundwater is unable to use for domestic usage. So, this study is proposed to solve the problem of iron and manganese in groundwater at Rumah Nur Kasih. This study focuses on a cascade aerator to increase the concentration dissolved oxygen and from the water sample. From the dissolved oxygen indication, the removal of iron (Fe3+) and manganese (Mn4+) can be determine. Aeration using cascade aerator is more suitable to use in Rumah Nur Kasih because it is low operating and maintenance cost laterally by transferring oxygen into water mass. The removal of iron (Fe3+) and manganese (Mn4+) could be occurred due to oxygen transfer in aeration process. The quality of groundwater at Rumah Nur Kasih consist high concentration of iron (11.56 mg/L) and manganese (0.38 mg/L). The groundwater only used for external usage such as cleaning purposes. In this study, cascade aerator physical model used with flow rate of 22mL/s. It was found that the concentration of dissolved oxygen is increase between 1.7-22 mg/L. The concentrations of iron and manganese removal were 11.56 mg/L to 10.88mg/L (5.8%) and 0.38mg/L to 0.37 mg/L (3.6%) respectively.