Introduction to Screens
Screens (Trash Racks) are key equipment in water and wastewater treatment systems, industrial facilities, power plants, oil & gas industries, and process units. They are designed and implemented to separate coarse solids, suspended materials, and foreign objects from fluid streams. These systems play a crucial role in protecting downstream equipment, extending system lifespan, and ensuring stable process performance.
In many industrial processes, the entry of solid materials such as plastics, fibers, wood, sand, sludge, and debris into pumps, heat exchangers, and sensitive equipment can cause clogging, corrosion, efficiency loss, and unplanned shutdowns. Screens act as the first line of defense, preventing such operational problems.
Screen Operation
Screens operate by creating a controlled mechanical barrier within the fluid flow path. As water or wastewater passes through bars, plates, or mesh structures, solid particles larger than the designed spacing are retained and separated from the flow, while the fluid passes through without causing excessive pressure drop.
In more advanced models, the collection and discharge of retained solids are carried out automatically and continuously. The collected materials are then transferred to disposal, compaction, or recycling units. This automated function reduces manpower requirements, enhances safety, and improves continuous system operation.