Water and Sewage Treatment Plants

Dewatering centrifuges are a crucial piece of equipment in water treatment plants and a recent overseas customer purchased dewatering centrifuges for their long-term project.  A dewatering centrifuge is a type of centrifugal separation device used in water treatment plants to remove excess water from solid-liquid mixtures. It's essentially a large, spinning drum that uses centrifugal force to separate the mixture into its component parts.

How Does it Work?

Here's a simplified explanation:

1. Feed material: The mixture of water and solids (e.g., wastewater, sludge, or sediments) is pumped into the centrifuge.
2. Centrifugal separation: The mixture enters the spinning drum, where the centrifugal force causes the heavier solids to be flung outward towards the walls of the drum.
3. Separation: As the mixture spins, the water and solids begin to separate due to differences in density. The lighter water forms a "discharge" or "peripheral" layer, while the heavier solids accumulate at the outer rim of the drum.
4. Dewatering: The centrifuge's design allows for efficient removal of excess water from the solids, reducing their moisture content. This process is called dewatering.
5. Product collection: The resulting dewatered solids are collected in a separate container or hopper.

Benefits in Water Treatment Plants

Dewatering centrifuges play a vital role in water treatment plants by:

1. Reducing wastewater volumes: By removing excess water from wastewater, dewatering centrifuges help reduce the overall volume of wastewater that needs to be treated, making it more efficient and cost-effective.
2. Improving effluent quality: By removing suspended solids and other contaminants, dewatering centrifuges help improve the quality of treated wastewater effluent, making it safer for discharge into receiving waters.
3. Increasing biosolids management: Dewatering centrifuges enable the production of dry biosolids (e.g., Class A or Class B biosolids) that can be easily handled, stored, and transported for land application or other uses.
4. Reducing energy consumption: By reducing the amount of water in wastewater, dewatering centrifuges can help reduce energy consumption and costs associated with treating and pumping large volumes of water.

Types of Dewatering Centrifuges

There are several types of dewatering centrifuges used in water treatment plants, including:

1. Solid bowl centrifuges: These are the most common type, using a stationary bowl with a rotating scroll to separate liquids and solids.
2. Disc stack centrifuges: These use a series of stacked discs to separate liquids and solids.
3. Screw press centrifuges: These combine screw pressing with centrifugal separation.

Conclusion

In summary, dewatering centrifuges are essential equipment in water treatment plants, enabling efficient removal of excess water from solid-liquid mixtures. By reducing wastewater volumes, improving effluent quality, increasing biosolids management, and reducing energy consumption, dewatering centrifuges play a critical role in ensuring effective and sustainable water treatment practices.