Access to an adequate water supply is a requirement for sustaining human life. Although much of the water on Earth is not fit for human consumption, the process of water purification renders the water to be safe for this use. Water purification involves a process by [Page 451]which undesired chemicals, organic and inorganic materials, and biological contaminants are removed from raw water. The purification of raw water takes place in various settings, including large-scale municipal water purification, portable and emergency water purification, industrial water purification, and small-scale distillation of water. All of these methods focus on the central goal of removing undesired che micals and contaminants from water. Different methods are favored to produce water for a variety of purposes. One of the major purposes ...