Introduction

Water is one of the most essential resources that we need to sustain life. However, we have been polluting our water sources for centuries. Human activities such as industrialization, agriculture, and urbanization have contributed to the pollution of water bodies. If we do not treat contaminated water, it can lead to the spread of waterborne diseases and contamination of aquatic life. Waste water treatment plants have become an essential solution to purify water and make it safe for human use. In this article, we will discuss how waste water treatment plants purify water.

Primary treatment

The first stage of water treatment is called the primary treatment. In this stage, the waste water is passed through a series of screens that remove any large debris such as sticks, paper, and plastics from the water. The water then enters a sedimentation tank where it is held for several hours. During this period, the heavy solid particles settle to the bottom of the tank through gravity. The sediment, which consists of organic matter, sand, and other solids, is then removed from the bottom of the tank with the help of mechanical scrapers.

Secondary treatment

The secondary treatment is designed to remove any dissolved solids and organic matter that remain after primary treatment. In this stage, the water is passed through an aeration tank where microorganisms are added to break down the organic matter into carbon dioxide, water, and other harmless materials. The microorganisms consume the dissolved organic matter and convert it into biological solids. After this process, the water is moved to a settlement tank where the biological solids settle to the bottom with the help of gravity. The remaining water is then passed through a sand filter to remove any remaining solids, and the clean water is ready for the next stage of treatment.

Disinfection

The third and final stage of water treatment is the disinfection stage. This stage is designed to kill any disease-causing microorganisms and viruses that may still be present in the water. In most cases, chlorine is used to disinfect the water, but other methods such as ultraviolet (UV) radiation, ozone, or hydrogen peroxide can also be used. Once the water has been disinfected, it is stored in a tank or reservoir before being distributed to households, industrial plants, and other water users.

Conclusion

Waste water treatment plays a critical role in keeping our water clean and safe for human consumption. Each stage of the water treatment process adds an extra level of purification that ensures the water is free of contaminants that can cause harm to human health. Water treatment plants are essential to remove harmful pollutants from our water supply and protect our environment from waste water pollution. It is our responsibility to use water wisely and to ensure that we do not pollute our water sources so that our waste water treatment plants can do their job effectively.