What is the process of adding chlorine to water until the demand has been met called?

The process of adding chlorine to water until the demand has been met is referred to as breakpoint chlorination. This term describes the specific point at which the amount of chlorine added exceeds the demand created by organic material, chloramines, and other chlorine-consuming compounds in the water. At this stage, chlorine not only reacts with these contaminants but also establishes a residual concentration of free chlorine in the water that is effective for disinfection.

By reaching this breakpoint, operators ensure that the water is adequately disinfected, improving its quality for safe consumption. This is an important step in water treatment because it ensures that enough chlorine remains in the water to provide protection against pathogens while minimizing the formation of undesirable byproducts related to incomplete disinfection.

In contrast, continuous chlorination refers to the ongoing addition of chlorine in smaller doses over time, without specifically addressing breakpoint levels. Shocking typically means applying a large dose of chlorine to quickly address a noticeable contamination issue but does not necessarily denote the level of chlorine needed to achieve breakpoint. Chlorine dosage simply describes the amount of chlorine added and does not indicate whether the demand has been fully met.