How a Clarifier Works in Water Treatment Plant

Water treatment plants are essential for supplying clean and safe drinking water to the communities they serve. One of the key processes involved in treating water is clarification, which involves removing suspended particles and impurities from the water. In this article, we will explore how a clarifier works in a water treatment plant and why it is such a crucial step in the water treatment process.

What Is a Clarifier?

A clarifier, also known as a sedimentation tank or settling tank, is a component of a water treatment plant that is used to remove suspended solids and other impurities from the water. The water to be treated is fed into the clarifier where it is allowed to settle, and the impurities in the water sink to the bottom of the tank. The clarified water is then released from the top of the clarifier and goes to the next stage of the water treatment process.

How Does a Clarifier Work?

The basic principle of a clarifier is based on gravity. The water to be treated is introduced into the clarifier, and as it flows through the tank, the suspended solids and other impurities in the water begin to settle to the bottom of the tank. As the impurities settle, they form a layer of sludge at the bottom of the tank, which can then be removed and disposed of.

The clarified water is then drawn off from the top of the tank through a series of weirs, which are adjustable barriers that allow water to flow over them while preventing the sludge from flowing over the top. The weirs are designed to allow the maximum amount of water to flow while still maintaining a stable layer of sludge at the bottom of the tank.

Types of Clarifiers

There are two main types of clarifiers used in water treatment plants: rectangular clarifiers and circular clarifiers. Rectangular clarifiers are typically used in smaller plants, while circular clarifiers are used in larger plants where higher flow rates are required. Both types of clarifiers operate using the same basic principle of gravity sedimentation, but the design and operation of the two types of tanks are slightly different.

Rectangular clarifiers are typically longer, shallower tanks that have a series of weirs on both sides of the tank. Circular clarifiers, on the other hand, are circular tanks that have a single central well that contains a mechanical scraper to remove the sludge from the bottom of the tank. The choice of which type of clarifier to use in a water treatment plant depends on the size of the plant and the flow rate of the water to be treated.

Conclusion

In conclusion, a clarifier is an essential component of a water treatment plant that is used to remove suspended solids and other impurities from the water. The basic principle of a clarifier is based on gravity sedimentation, and there are two main types of clarifiers used in water treatment plants: rectangular clarifiers and circular clarifiers. Choosing the right type of clarifier is crucial to the efficient and effective operation of a water treatment plant, and the proper maintenance of the clarifier is essential to ensuring its continued operation over time.