Wastewater Screening


Screening is an essential process in wastewater treatment that involves the removal of large solid objects and debris from the incoming wastewater. It is typically the first step in the treatment process and helps protect downstream equipment and processes from damage or clogging.


The captured solids are then typically collected and disposed of separately, either through landfilling or pipes, pumps, and other equipment, ensuring the smooth operation of subsequent treatment processes.

Benefits of effective screening

1. Protection of downstream equipment: by removing large solid objects and debris, screening helps prevent damage and clogging in pumps, pipes, and other equipment. This extends the lifespan of the equipment and reduces maintenance and repair costs.

2. Improved efficiency: efficient screening ensures that smaller particles and pollutants can be effectively treated in subsequent treatment processes. By removing larger solids, the overall treatment efficiency is enhanced, leading to better water quality outcomes.

3. Reduced operational issues: coarse screening helps prevent blockages and disruptions in the treatment process, minimizing operational issues and downtime. This allows for a more consistent and reliable wastewater treatment operation.

4. Environmental protection: effective coarse and fine screening prevents the release of large solid materials into the environment, reducing the risk of pollution in receiving water bodies. This helps protect aquatic ecosystems and supports the overall environmental health.

5. Compliance with regulations: many wastewater treatment facilities are required to meet specific regulatory standards for effluent quality. Proper screening ensures that the treatment process meets these standards, helping facilities remain compliant with environmental regulations.

6. Enhanced public health and safety: screening removes potentially harmful materials from wastewater, reducing the risk of contamination and the spread of diseases. This contributes to the protection of public health and safety.

Overall, effective screening in wastewater treatment maintains the efficiency, reliability, and environmental sustainability of the treatment process. It helps protect equipment, improves water quality, ensures compliance with regulations, and ensures the protection of public health and environment

Screening methods

Bar screens: bar screens consist of vertical or inclined bars spaced at regular intervals. Wastewater flows through the gaps between the bars, allowing liquid to pass while retaining larger solids. Bar screens can be manually or mechanically cleaned, with the collected solids typically removed using rakes or conveyor systems.

Rotary drum screens are cylindrical-shaped screens that rotate to separate solids from wastewater. As wastewater flows through the rotating drum, solids are captured on the screen surface and lifted out of the water. The collected solids are then discharged and removed for further treatment or disposal.

Step-type fine screens are designed with alternating fixed and movable bars. They are used to capture smaller particles and debris, and often in conjunction with other screening methods to provide additional filtration and removal of finer particles.. Wastewater flows through the gaps between the bars, and solids are retained on the screen surface. The movable bars periodically lift the captured solids, allowing them to be removed and collected for disposal.

Automatic bar screens incorporate automated technologies such as sensors, controls, and mechanical cleaning mechanisms. These systems can monitor the screen performance, adjust cleaning cycles, and optimize the screening process based on real-time conditions.

The selection of a screening method depends on the size and nature of the solids present in the wastewater, the desired level of screening efficiency, and the specific requirements of the treatment plant.

Contact us today so we can work out together wchich screen is most suitable to your needs!