Experiment study of the effect of salt on the stability of solar ponds

摘要

The sun is the largest source of renewable energy and this energy is abundantly available in all part of the earth. One way to trap solar energy is through the use of salt-gradient solar ponds (SGSP). Collecting and storing of energy for this device is in one system, so the heat in summer can be utilized in winter. A typical SGSP consists of a pond containing three density stratified layers. The stability duration and the efficiency of a SGSP depend closely on the self-maintenance of the NCZ layer, which itself depends on the type of the used salt. This article reviews nonconvective solar ponds, the problems encountered in their operations and the effect of the used salts. Three salts: NaCl, MgCl, and CaCl2 were tested in a laboratory set-up under different operating conditions. Temperature and concentration gradients were developed by heating the pond from the bottom. The results showed that MgCl and CaCl2 stratification remains stable until the temperature reaches around 70 degrees C while NaCl layers were mixed at 55 degrees C. (c) 2018 American Institute of Chemical Engineers Environ Prog, 38: 699-705, 2019