Cooling water systems are exposed to many types of corrosion and scale problems. Water-formed deposits result from naturally occurring minerals precipitating from water to form scale. Scales built up on surfaces can be extremely hard and difficult to remove. These phenomena have a great economic impact, since the first involves deterioration of metallic surfaces by the medium, and the second causes loss of capacity for thermal exchange. Scaling and corrosion are usually interdependent. When non -uniform formation of scale occurs, corrosion is often present particularly under the deposit. This...