Kloorimine

Kloorimine, or chloramine, refers to a family of chemical compounds in which one or more chlorine atoms are covalently bound to nitrogen. The principal species are monochloramine (NH2Cl), dichloramine (NHCl2), and trichloramine (NCl3). In water treatment they form when chlorine reacts with ammonia or ammonium ions, usually under controlled pH and chlorine-to-ammonia ratios. Monochloramine is the common disinfectant used in many municipal systems, due to its relative stability and ability to maintain a disinfecting residual as water travels through distribution networks. Dichloramine and trichloramine form at higher chlorine levels or lower pH and are more reactive and volatile; trichloramine is particularly associated with eye and respiratory irritation and with odors in poorly aerated pools.

Chloramines have advantages over free chlorine, including slower consumption by organic matter and lower formation of certain disinfection byproducts, such as trihalomethanes. They are, however, less potent disinfectants on a per-molecule basis and may require longer contact times or higher dosages. Operationally, chloramination requires careful control of pH, ammonia levels, and residuals to balance disinfection efficacy with byproduct formation and potential irritant effects.

Safety and environmental notes: chloramines are irritants and should be handled with appropriate precautions in industrial settings. In drinking water, they persist as residual disinfectants but can be off-gassed in indoor pools, contributing to odors. See also chlorination, drinking water disinfection, and disinfection byproducts.