Introduction to desalination : principles processes and calculations The title of this book includes the word desalination. Dictionary.com (2012) defines desalination as the process of removing salt esp from sea water so that it can be used for drinking or irrigation. Thus desalination is a process that produces potable water. The reader should keep in mind and this will be discussed later in the book that there are other processes available for producing potable water many of which are currently uneconomical. For this reason the book primarily deals with desalination. The general topic of potable water also considered and is addressed in several of the paragraphs to follow. The worlds total water is enormous compared with the presently conceivable needs of man yet there is a growing water problem. Of the 1.39 billion km3 (332 million mi3) of water in the earths crust 99% is salty and useful neither for irrigation by present techniques nor for the majority of mans other needs