C © Owned by the authors, published by EDP Sciences, 2015 Experimental study of evaporation of horizontal films of water–salt solutions

Abstract. The present studies were carried out for the horizontal films (thin layers) of water and water solutions of NaCl, CaCl2, LiCl, and LiBr with different solubility characteristics, as well as with specific features of formation and decay of water hydrates. Required volume of solution Vo of given weight concentration o, preliminary heated to the working surface temperature, was put in one step on the horizontal bottom of the bowl, heated to working temperature tCT, by means of volume batchers Thermo Scientific. After evaporation completion, the final mass of solution and form of their residue were registered. At the final stage of evaporation formation of NaCl crystals and water hydrates of CaCl2 · 2H2O, LiCl · H2O, and LiBr · 2H2O occurred. The processes of evaporation and boiling of liquid films are one of important directions of development of modern thermal physics. This problem becomes much more complicated, when the objects of study are different kinds of mixtures and solutions used in refrigeration, power engineering, petrochemistry and chemical technologies. Evaporation of solutions is accompanied by changes in their concentration; under the certain conditions separation of the solid phase (crystals of salt hydrates) is also possible. The present studies were carried out for the horizontal films (thin layers) of water and water solutions o