Total and speciated metals and metal scales in domestic water

Abstract

A major part of chemical contamination in domestic water is the release of metals from metallic water distribution systems and the formation of metal scales. The objective of this study is the assessment of well and municipality domestic water quality in houses that use metallic water distribution system in terms of total and speciated metal content and metal scales. An XRF (X-Ray fluorescence) technique was used to determine metal content used in the water distribution system of studied houses. Domestic water samples were collected from taps of 106 houses during the dry season. The following water parameters were measured: pH, alkalinity, DO (dissovled oxygen), Ca2+, Mg2+, Cl- , SO4 2-, PO4 3-, Fe3+, Zn2+, Cu2+, Pb2+ and Cd2+. The corrosivity of water or scale indices were determined using the software AquaChem. The metal species and metal scales were predicted using the PHREEQC geochemical model. The results from this study revealed an inverse relation of Cl- with scale indices and metal scale formation except f