“COME AND GO” SCRAPING BRIDGE
I trattamenti meccanici a cui vengono sottoposti i fanghi fanghi biologici hanno il compito di separarli dal resto del refluo chiarificato o trattato.
Infatti, dopo un tempo opportuno di permanenza nella vasca di ossidazione, i fanghi biologici o attivi passano al sedimentatore secondario dove, sedimentando, si separano dal refluo trattato o chiarificato.
HOW IT WORKS
Bridge is installed on a concrete tank with rectangular shape, which permits to sedimentable solids present in the water to treat, to settle on bottom. Bottom scrapers, anchored to the movable walkway positioned on walls of tank, scrape sludge and convey it in a hopper located at the end of tank.
Translation of bridge is very low and is in two phases: the first ahead, with bottom scrapers lowered, so to scrape sludge in the bottom. The second back, with scrapers lifted, to permit to solids to settle again.
Clean water without solids overflows from top part of tank.
HOW IT IS BUILT
Machine is composed by:
A movable walkway made with tubulars, with suitable beams of stiffening, walking floor, translation trolleys, banisters basing rules in force, all in hot galvanized steel.
A pair of drive and idle wheels in cast-iron coated in polyurethane, and guiding wheels inside tank.
A movable surface scraper to collect scums in surface.
A series of lattices and bottom scrapers in carbon steel hot galvanized, with guiding wheels in nylon and support in stainless steel 304.
A motorization for translation of bridge, directly coupled to wheels, by a shaft in stainless steel.
A unique gearmotor of lifting for bottom and surface scrapers.