Use of Solar Still in Heavy Metals Removal from Kitchen Wastewater

Abstract

Indiscriminate discharge of wastewater into the environment can lead to environmental pollution. Heavy metals present in wastewater can infiltrate into the ground to cause groundwater contamination. In this study, a solar still was employed in the removal of heavy metals from domestic wastewater. Five wastewater samples with high heavy metal contents were kept in a solar still and subjected to heat from the sun. The solar still was constructed using locally available materials. The concentration of Iron (Fe), Zinc (Zn), Manganese (Mn), Chromium (Cr) and Cadmium (Cd) in the untreated and treated wastewater samples were determined. The study revealed a drastic reduction in the heavy metal content of the treated wastewater, however, the heavy metal content of most of the treated wastewater samples did not fall within World Health Organization (WHO) limit for potable water. Remarkably, The Zn content of four out of the five treated wastewater samples fell within WHO limit for potable water except for sample 2 which witnessed a drastic reduction from 13.9 to 3.28 mg/L but still did not meet up with WHO limit of 3 mg/L. The treated wastewater can be safely discharged into the environment; however, further treatment is required to make the water safe for human consumption.