How is water disinfected in a sewage treatment plant

Water is vital for all forms of life on our planet. However, due to various human activities, there are many contaminants in the water such as carcinogens, pathogens, and heavy metals. These contaminants make the water unsafe for human consumption and can cause various diseases. To make the water safe for consumption and use, it needs to be treated in a sewage treatment plant. One of the most important steps in the treatment process is disinfection. In this article, we will discuss how water is disinfected in a sewage treatment plant.

Chlorination

Chlorination is one of the most common methods of disinfection used in sewage treatment plants. In this method, a small amount of chlorine gas or sodium hypochlorite is added to the water. The chlorine reacts with the contaminants present in the water and destroys them. Chlorination is a simple and effective method of disinfection that can kill various pathogens and viruses such as bacteria, viruses, and protozoa.

Ultraviolet radiation

Ultraviolet radiation is another method of disinfection used in sewage treatment plants. In this method, the water is exposed to ultraviolet light, which kills the organisms present in the water. The ultraviolet light damages the DNA of the organisms and renders them harmless. This method of disinfection has become increasingly popular in recent years as it does not add any chemicals to the water and does not produce any harmful byproducts.

Ozone disinfection

Ozone disinfection is a relatively new method of disinfection used in sewage treatment plants. In this method, ozone gas is injected into the water. The ozone gas reacts with the contaminants present in the water and destroys them. Ozone disinfection is a highly effective method of disinfection that can kill a wide range of microorganisms such as bacteria, viruses, and protozoa. It is also a more environmentally-friendly method of disinfection as it does not produce any harmful byproducts.

Chloramine disinfection

Chloramine disinfection is another method of disinfection used in sewage treatment plants. In this method, ammonia is added to the water before adding chlorine. The ammonia and chlorine react and form chloramines. Chloramines are highly effective disinfectants that can kill various pathogens and viruses such as bacteria, viruses, and protozoa. Chloramine disinfection is a more stable method of disinfection than chlorination and does not produce any harmful byproducts.

Conclusion

In conclusion, water disinfection is an essential step in the sewage treatment process. The most common methods of disinfection used in sewage treatment plants are chlorination, ultraviolet radiation, ozone disinfection, and chloramine disinfection. Each method has its advantages and disadvantages, and the choice of the method depends on various factors such as the type of contaminants present in the water, the size of the treatment plant, and the cost of the disinfection process.