Screening at intake of a wastewater treatment plant (WWTP) to retain and remove solid objects found in the influent wastewater; like plastics, wood, metals, paper, rages to prevent damage and clogging of downstream equipment and piping. Screens can be classified based on the size of the opening in the screening element and the solid objects removal mechanism.

• – Coarse screens
• – Fine screens
• – Microscreens