Introduction

Sewage treatment plants are essential for maintaining the hygiene of a community. They are responsible for purifying the sewage water that is released from households, industries, and commercial establishments. The purified water is then released back into the environment without causing any harm to the ecosystem. In this article, we will learn about how water is purified in sewage treatment plants.

Primary Treatment

The first stage of wastewater treatment is the primary treatment. During this stage, large debris and solids are removed from the wastewater. The sewage water is passed through a series of screens and grit chambers that remove the larger solids. After this, the sewage water is allowed to settle in large holding tanks. This allows the smaller particles to sink to the bottom of the tank while the grease and oils float to the surface. These substances are then removed using skimming mechanisms. The water that remains is then ready to undergo the secondary treatment.

Secondary Treatment

The second stage of wastewater treatment is the secondary treatment. During this stage, biological processes are used to remove dissolved organic matter and other pollutants. The sewage water is introduced to aeration tanks where air is pumped into the water to provide oxygen to the microorganisms that are added to the water. These microorganisms break down the organic matter in the sewage water and convert it into carbon dioxide, water, and other harmless substances.

Tertiary Treatment

The third stage of wastewater treatment is the tertiary treatment. During this stage, any remaining solids or contaminants are removed from the water. There are several methods used for tertiary treatment including chemical treatment, filtration, and disinfection. In chemical treatment, chemicals like chlorine or ozone are added to the water to disinfect it. In filtration, the water is passed through a series of filters that remove any remaining solids or pollutants. Disinfection may also be performed using ultraviolet radiation or other means.

Final Disposition

Once the water has undergone the three stages of treatment, it is ready to be disposed of. The purified water can be returned to the environment in a number of ways. It can be released into rivers, lakes, and oceans. It can also be used for other purposes like irrigation or firefighting. In some cases, the purified water is used as a source of drinking water. To ensure that the water is safe for human consumption, it undergoes further treatment to remove any remaining contaminants. This is known as the fourth stage of wastewater treatment.

Conclusion

In conclusion, sewage treatment plants play a vital role in maintaining a community's hygiene by purifying the wastewater that is released from households, industries, and commercial establishments. The three stages of treatment, primary, secondary, and tertiary, are used to remove all the impurities and pollutants from the water. The final product is a purified water that is safe to be released back into the ecosystem or used for other purposes. The fourth stage of wastewater treatment ensures that the water is safe for human consumption. This whole process is critical for protecting the environment and human health.