Water Quality on Solar Water Heaters in Remote Islands
Abstract
The use of solar water heaters (SWHs) in Taiwan's remote islands has encountered scaling and corrosion problems attributed to sources of water. In this study, the Langelier Saturation Index (LSI), Ryznar Stability Index (RSI), Puckorius Scaling Index (PSI) and Larson-Skold Corrosive Index (LSCI) were employed to assess scaling and corrosion caused by tap-water and groundwater used for SWHs in Penghu, Kinmen, and Lienchiang Counties. The LSI, RSI and PSI results show a slight scaling tendency in Penghu County, but there is a corrosion tendency in Kinmen and Lienchiang Counties. Nevertheless, all LSCI values show a serious corrosion tendency. In addition, chloride ion (Cl-) concentration levels are all higher than 35 mg/L, resulting in corrosion found in absorbing plates of SWHs using 304 stainless steel. Therefore, more corrosion-resistant metals are required for SWHs.
Keywords
Solar water heater, remote islands, water quality, scaling, corrosion