A Freeman Scholar Lecture: Desalination: Some Fluid Mechanical Problems

Abstract

Despite the fact that the world’s need for desalinated water is becoming more urgent, the ability to economically desalinate on a large scale still remains a goal rather than a reality. The present review examines distillation, freezing, electrodialysis, and reverse osmosis which together account for essentially all of the installed desalination capacity. Although distillation is by far the most widely employed system, emphasis is placed on the other three methods because of their potential. It is shown that for each process one or more of the critical technical problems which lead to increased fresh water costs is associated with a fluid mechanical phenomenon. The review attempts to present the critical fluid engineering problems, and where possible the solutions and their consequences in relation to the goal of obtaining desalted water economically.