What is Coanda Screen

JX Filtration October 25, 2024 Coanda screen

The Coanda screen, a highly efficient and environmentally friendly solid-liquid separation device, is playing an increasingly important role. It is widely used in wastewater treatment, water purification, industrial wastewater processing, and has become an indispensable tool for water quality improvement due to its unique advantages.

Working Principle

The working principle of the Coanda screen is based on the combined effects of gravity, centrifugal force, and filtration. As wastewater flows through the distributor at the top of the equipment, it is evenly spread across the screen surface. Solid particles are trapped by the screen, while the filtered clean water flows through the screen slots.

Under the influence of the water flow, solid matter is gradually pushed to the lower end of the screen plate and discharged, thus achieving solid-liquid separation. During this process, the Coanda screen effectively reduces the concentration of suspended solids in the water and lessens the load on subsequent treatment stages, ensuring the smooth operation of pumps, pipelines, and instruments.

Performance Advantages

High Efficiency: This equipment is renowned for its efficient solid-liquid separation capability, significantly reducing the concentration of suspended solids and enhancing water purification. In wastewater treatment, its BOD (Biochemical Oxygen Demand) removal efficiency is comparable to primary sedimentation. In municipal wastewater treatment, the flow capacity of the screen can reach up to 2,000 m³/day per meter of screen width, equivalent to a 180 m² clarifier.
Energy Saving and Eco-friendly: The device operates using the water’s own energy without requiring additional power sources, resulting in energy-free operation. This design not only reduces operating costs but also minimizes energy consumption and carbon emissions, aligning with modern environmental protection concepts.
Easy Maintenance: With a simple structural design, the equipment is easy to install and dismantle. The screen is typically made from corrosion-resistant materials like stainless steel, offering high mechanical strength and durability. Regular washing is sufficient to maintain its operation, keeping maintenance costs relatively low.
Wide Applicability: The equipment is suitable for various solid-liquid separation applications across different wastewater types. It is used in industries such as food processing, textiles, dyeing, papermaking, and also in heavy industries like chemicals, pharmaceuticals, and wood processing. Additionally, it is widely applied in municipal wastewater treatment, river management, and seawater desalination projects.