What is a method used to introduce oxygen into water in treatment facilities?

Aeration is the method specifically used to introduce oxygen into water in treatment facilities. This process involves agitating or diffusing air into water, which enhances the solubility of oxygen in the water. The primary purpose of aeration is to increase the dissolved oxygen concentration, which is crucial for supporting aquatic life and for the effectiveness of certain biological treatment processes.

In aeration, techniques such as spraying water into the air or using diffusers to create small bubbles are commonly employed. By doing so, the surface area of the water is increased, allowing for more efficient gas exchange between the water and the atmosphere. This added oxygen is essential for the survival of aerobic microorganisms that break down organic pollutants during biological treatment.

The other methods mentioned do not introduce oxygen into water in the same way. Coagulation and flocculation refer to processes used to remove suspended particles from water by using chemicals that cause these particles to clump together, while chlorination involves the addition of chlorine for disinfection purposes, not for oxygen introduction. Consequently, aeration stands out as the dedicated technique for enhancing oxygen levels in water treatment.