What results from breakpoint chlorination?

Breakpoint chlorination is a water treatment process that occurs when the amount of chlorine added to water reaches a level sufficient to react with all the organic compounds and ammonia present. This reaction reduces combined chlorine and ultimately leads to the formation of free chlorine in the water.

When breakpoint chlorination is achieved, it results in the destruction of combined chlorine compounds, which are often responsible for unpleasant tastes and odors. As a result, the excess chlorine beyond the breakpoint level becomes available as free chlorine. The presence of this residual free chlorine is essential because it provides ongoing disinfection and ensures the continued safety of drinking water by eliminating pathogens.

Other potential outcomes of chlorination, such as the production of sodium hypochlorite, bacterial growth, or complete chlorine removal, do not reflect the purpose or result of reaching the breakpoint. Sodium hypochlorite is a compound formed when chlorine is dissolved in water and is typically introduced into the process rather than being a direct result of breakpoint chlorination. Bacterial growth contradicts the primary goal of chlorination, which is to kill or inhibit the growth of bacteria. Complete chlorine removal entails eliminating chlorine entirely, which is also counterproductive to the disinfection process aimed at maintaining a level of free chlorine. Thus, the generation of a residual