Yu Z, Yang JS, Yao RJ. An investigation of the factors affecting saline ice melting processes and desalination. Clean – Soil, Air, Water, doi: 10.1002/clen.201700628
Abstract
In this study, a laboratory simulation experiment was undertaken to examine five factors affecting the melt‐water quality and quantity changes during the melting process of saline ice: salinity, freezing/melting temperature, ions composition and the freezing method. A field experiment was conducted to evaluate the freeze–thaw effects on desalination of saline water under natural conditions. The results showed that for all treatments, the melt‐water salinity sharply decreased during the first half of the melting process. Saline ice with a higher original salinity had higher melt‐water salinity. The desalination rates increased with the original salinity when water salinity was less than 15 g L−1, but production of available water showed the opposite trend. Saline ice frozen at –15°C increased production of available water by approximately 23.66% relative to ice formed at –10 and –20°C. Nearly 25% of available water was lost during melting when the ambient temperature increased to 30°C. The addition of Ca2+ significantly reduced desalination rates compared with saline ice composed of solely NaCl. The unidirectional‐freezing method significantly accelerated the salt exclusion, and increased desalination rates. The results of field experiment showed that the salinity and sodium adsorption ratio (SAR) sharply decreased with the saline ice melting. These results indicated that saline water could be desalinized by freeze–thaw process, and the desalinating efficiency was controlled by the salinity of water, freezing and melting temperatures, the freezing method and original ions composition.
