Aeration in water treatment plants is primarily used to accomplish which of the following?

In water treatment plants, aeration is primarily used to remove dissolved gases, particularly undesirable gases like carbon dioxide and volatile organic compounds, from the water. Through the process of aeration, air is introduced into the water, which creates a mass transfer of gases between the water and the atmosphere.

This action effectively reduces the concentration of gases dissolved in the water, enhancing water quality and improving the overall treatment process. For example, by removing carbon dioxide, aeration can help in stabilizing the pH of the water, which is beneficial for subsequent treatment processes.

While increasing temperature might occur as a side effect due to the contact between air and water, that is not the primary goal of aeration. Similarly, although aeration can lead to an increase in pH levels by removing carbon dioxide, this is a secondary benefit rather than the main purpose. Adding minerals is also not a function of aeration; instead, this process focuses on gas exchange rather than altering the mineral content of the water.