Rotary Drum Screen Overview

JX Filtration January 18, 2024 Rotary Drum Screen

Due to factors such as temperature and processing capacity affecting the operation of wastewater treatment plants, it is challenging to maintain the stability of secondary sedimentation tank sludge. Especially during heavy rainfall, the short-term excessive sewage treatment volume leads to increased pollutants and suspended solids in the effluent.

The Rotary Drum Screen is an equipment used for further treatment after the secondary sedimentation tank. Through this equipment, sewage can be further processed, ensuring that the effluent is almost free of solid particles, thus guaranteeing the stability of the effluent.

Working Principle

The Rotary Drum Screen operates through rotary drum filtration. The mechanical equipment consists of a series of horizontally installed, rotatable filter discs mounted on a central shaft, with a maximum immersion volume of up to 60%. Typically, each disc is composed of 6 or 12 components, each with two filter panels fixed to plastic components through a thermal processing technique.

Wastewater flows from the inside to the outside through the disc for filtration, and the filtered liquid flows out from the mechanical end.

During filtration, the disc remains stationary. Under the action of gravity, solid substances deposit on top of the disc. As the filtration time extends, the mesh fabric is covered by the trapped solid material, leading to an increase in pressure differential.

Once the preset maximum pressure differential is reached, the disc starts to rotate. The filtration pump is activated to directly transport the filtered sewage to the cleaning rod, and the mesh fabric is cleaned through targeted flushing using nozzles.

The solids cleaned off are flushed into the discharge hopper installed in the central tube.

Advantages

The equipment is distinctive in that it uses an all-stainless-steel rotary filter with a titanium-containing stainless steel mesh. The mesh material is hydrophobic, ensuring that microorganisms do not breed on the mesh, reducing the likelihood of clogging. Conventional microfiltration uses polyurethane, which is hydrophilic and prone to bacterial growth, affecting the equipment's flow capacity.
Filtration employs an internal-to-external filtration method, with clear water in the pool, providing good sensory properties and not affecting the external environment.
Each filter disc is composed of 6 or 12 individual sections that can be disassembled separately, facilitating maintenance and installation.
The rotary drum filter can be installed individually in a trench, secured by expansion bolts, making it easy to install and ensuring reliable operation.
Low energy consumption during equipment operation.
The rotary drum is equipped with high-pressure flushing water, ensuring both clean filter discs and filtration capacity.
Minimal head loss, with the total head loss of the equipment not exceeding 300mm.