Screen Manual and Auto

In wastewater treatment, screens are used to filter out coarse materials either manually or automatically. At wastewater treatment plants, screening is the first unit activity. To minimize damage and clogging of downstream equipment, pipelines, and appurtenances, screening eliminates items such as rags, paper, plastics, and metals. Coarse and fine screens are used in some modern wastewater treatment systems. Screens are of two types:

a). Coarse Screens
Coarse screens typically have apertures of 6 mm (0.25 in) or bigger and remove heavy particles, rags, and trash from wastewater. Mechanically and manually cleaned bar screens, as well as trash racks, are examples of coarse screens.

b). Fine Screens
Fine screens are commonly employed to eliminate particles that could cause difficulties in downstream processes, especially in systems that don't have primary treatment. Fine screens typically have openings ranging from 1.5 to 6 mm (0.06 to 0.25 in).

After coarse or fine screens, very fine screens with apertures of 0.2 to 1.5 mm (0.01 to 0.06 in) can reduce suspended particles to values similar to those produced by primary clarifying.

The Mechanical Bar Screen is an automatic equipment that is installed directly in the channels of wastewater treatment plants. During the continuous operation phase, what does not pass through the spacing of the grid is collected and discharged from the discharge spout located at the top of the machine.

The use of this type of mechanical equipment is optimal to obtain fine screening from 1mm to 40mm. The screening is composed of elements multi rake in reinforced techno polymer with high mechanical and thermal performance.

The automatic cleaning or self-cleaning of the filtering elements of this equipment is done by nozzles placed in the upper part of the machine and from 2 systems of brushes which allow obtaining the clean of the filtering screen at each rotation.