Experimental study on energy conversion in static flash evaporation of aqueous NaCl solution

Energy conversion during static flash of aqueous NaCl solution was analyzed on the basis of experiments with an initial waterfilm concentration ranging from 0 to 0.26 (saturated at room temperature), initial height from 0.1 m to 0.4 m, and superheat from 1.8 K to 55.9 K. In the energy released from superheated waterfilm, the present study focused on the portion that transformed into the latent heat of flash steam; this fraction of the total released energy was defined as energy conversion efficiency (ECE). Results suggested that ECE highly depended on both evaporation and steam-carrying effect. Second, ECE decreased monotonically with rising initial height of waterfilm in both non-crystallization and crystallization regions. Finally, with rising superheat or initial concentration of waterfilm, ECE decreased within the non-crystallization region but increased within the crystallization region.