Definition - What does Breakpoint Chlorination mean?
Breakpoint chlorination is the point where the demand for chlorine has been fully satisfied in terms of chlorine addition to water.
When chlorine is added to water, a reaction is produced in the compounds present in the water. These compounds utilize the chlorine, resulting in zero chlorine residual.
Corrosionpedia explains Breakpoint Chlorination
Once chlorine has been added to water, it is consumed by a type of chemical reaction that has a net effect of increased concentration of chlorine. For typical addition of chlorine, the rate of reaction instantly speeds up, reducing the concentration of chlorine. This is because chlorinated compounds acquire more chlorine.
The pace at which the chlorine atom is added is comparatively slow, but the rates can be faster for the following reactions since chlorinating potentiates an activity called reactivity. Once almost all of the chlorine reactions are accomplished, adding more chlorine leads to permanent residual.
The period wherein the concentration of chlorine goes into an upward slope is called the "breakpoint." In some cases, there can be no breakpoint seen because various organic compounds react at different rates.
Breakpoint chlorination is usually measured to determine when chlorination has been satisfied. This is a common practice in disinfecting water in industrial water systems as well as swimming pools. It is one of the most typical forms of chlorination where adequate chlorine is incorporated into the water to achieve the breakpoint, keeping the water well chlorinated and appropriate for its intended use.