Sereco - Model PRVR -Backward and Forward Scraper for Rectangular Clarifier

The PRVR type consists of a traveling girder used as a walkway, a couple of lateral sliding trolleys, an articulated system for sludge scraping and scum overflow, gear motor for lateral trolleys drive, drive unit of articulated system for bottom sludge scraping and control panel. The gear motor and the drive unit are fitted on in correspondence of bridge centerline. The water inlet is located on one of the two short sides of the tank. On the outward journey, the sludge is scraped from the bottom by the scraper in a direction opposite to the horizontal component of the sedimentation speed. The floating materials are gathered by the surface scraper at one of the two stages. The control panel is located on the bridge and is complete with devices for the manual and automatic operation. The protection against overloads is carried out by a control system which periodically controls the bridge working cycle.