ABSTRACT
Products added to drinking water or to water during its treatment purification steps to purify, disinfect, or stabilize it are considered to be reagents. Among the reagents some play a role of primary importance; for example, disinfectants are determinants for treatment, such as coagulants and products used for pH correction. Furthermore, some chemicals may have a significant auxiliary importance, such as the use as flocculation aids. Other derivatives or mixtures are injected directly or indirectly into the water for particular purposes (e.g., momentary disinfection of part of the mains). Still other products (e.g., adhesives, lubricants) may be used during the laying of mains.
