Disinfection of drinking water is done to remove bacteria.

Bacteria are microscopic organisms that can be present in water sources such as rivers, lakes, and wells. While not all bacteria are harmful, some can cause illnesses and diseases when consumed. Therefore, it is important to remove or kill these bacteria to ensure that the water is safe for drinking.

There are several methods of disinfecting drinking water to remove bacteria:

1. Chlorination: Chlorine is commonly used as a disinfectant in water treatment. It is added to the water in the form of chlorine gas or chlorine compounds such as sodium hypochlorite. Chlorine kills bacteria by disrupting their cell walls and interfering with their metabolic processes.

2. UV disinfection: Ultraviolet (UV) light can also be used to disinfect water. UV light damages the DNA of bacteria, making them unable to reproduce and cause infections. This method is effective against a wide range of bacteria and does not leave any residual chemicals in the water.

3. Ozonation: Ozone is a strong oxidizing agent that can kill bacteria. It is produced by passing oxygen through a high-voltage electrical discharge. Ozone reacts with the cell walls of bacteria, causing them to break down and die. Ozone is effective against a variety of bacteria and viruses.

4. Filtration: Filtration is another method used to remove bacteria from drinking water. Water is passed through a filter that traps bacteria and other contaminants. Filters can be made of materials such as sand, activated carbon, or ceramic. Filtration is often used in combination with other disinfection methods to provide a multi-barrier approach to water treatment.

In conclusion, disinfection of drinking water is done to remove bacteria, which can cause illnesses and diseases. Methods such as chlorination, UV disinfection, ozonation, and filtration are used to kill or remove bacteria from water sources, ensuring that the water is safe for consumption.