How is chlorination used in water treatment?

Chlorination is used in water treatment to kill bacteria, viruses, and other microbes, making the water safe to drink.

Chlorination is a popular method of water treatment due to its effectiveness and affordability. It involves adding chlorine or chlorine compounds to water. This process is known as disinfection and is crucial in ensuring that the water we consume is free from harmful microorganisms.

Chlorine is a powerful oxidising agent. When it is added to water, it reacts with the water to form hypochlorous acid (HOCl) and hydrochloric acid (HCl). The hypochlorous acid is particularly effective at killing bacteria and viruses. It does this by penetrating the cell walls of the microorganisms and disrupting their metabolic processes, effectively killing them.

The amount of chlorine that needs to be added to the water depends on several factors, including the quality of the water, the temperature, and the pH level. Too little chlorine will not effectively kill all the microorganisms, while too much can lead to a strong chlorine taste and smell in the water, which can be off-putting. Therefore, it's important to get the balance right.

Chlorination is not only used for drinking water, but also in swimming pools, cooling towers in power plants and other industrial applications. Despite its widespread use, it's important to note that chlorination does not remove other contaminants such as heavy metals, salts, and chemicals from the water. Therefore, it is often used in conjunction with other water treatment methods.

In summary, chlorination is a vital process in water treatment. It ensures that our water is safe to drink by effectively killing harmful microorganisms. However, it must be used correctly and in the right amounts to be effective and to maintain the quality of the water.