عنوان مقاله [English]
Today, the problems of water scarcity, limited water resources, high volume of evaporation, and water losses have highlighted the importance of ways to reduce the rate of evaporation from small and large reservoirs. In order to increase water supplies, reducing losses through evaporation have been investigated both in theoretical aspects and in practical applications in a number of countries (Ali et al., 2011; Barnes, 2008; Coleman, 2000). One of the most important methods for water conservation is the application of chemical films for reducing evaporation from open water resources such as reservoirs, lakes, and the like (Craig et al., 2007). These applications are especially important in arid and semiarid areas for the purpose of reducing evaporation rates from water surfaces. Most materials suggested by researchers for reduced evaporation have been the fatty alcohols containing 14 to 22 carbon atoms, such as Tetradecanol (C14), Pentadecanol (C15), Xadecanol (C16), Heptadecanol (C17), Octadecanol (C18), Nonadecanol (C19), Eicosanol (C20), Heneicosanol (C21), and Docosanol (C22).The two most favoured compounds used for evaporation control are Hexadecanol (C16H33OH) and Octadecanol (C18H35OH) although more complex variants are currently in development since they offer high resistance to water evaporation. In fact, small flakes of the solid alcohol spread spontaneously to form monolayers with a high molecular packing density (Manges and Crow, 1966). In this study, a new chemical method has been used to reduce the rate of evaporation. A new combination is made from polyvinyl butyral resin and Hexadecanol and Octadecanol as two fatty alcohols to reduce of evaporation from surface water sources and wastewater tailings dam of Sarcheshmeh Copper Complex.