BRIDGE AT CENTRAL TRACTION
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 in an ascensional flow cylindrical settler, having base with shape like a reversed cone. Mixture of water and sludge enters inside central diffuser cylinder. Solids sedimentable by gravity falls in the bottom where, by suitable scrapers fixed to the rotating shaft, are deliverd in the central zone of cone, and extracted by pump. Clean water overflows from a profile located in the peripheral zone of settler. Floating particles are kept by a surface scraper located inside tank and conveyed to a small tank of collection and evacuation.
HOW IT IS BUILT
The machine is composed by:
a motorization with dynamometric device, for models till tank diameter
13 m. For tanks with bigger diameter, motorization is equipped with fifth wheel and pinion.
A central shaft coupled to motorization and kept in axis by a centering located on bottom of tank.
A series of lateral arms and tie-rods in stainless steel, fixed to shaft with an adjustable system, with function to support bottom scrapers.
A series of bottom scrapers fixed to lateral arms with an adjustable system of inclination and position.
A central diffuser cylinder made in hot galvanized steel.
A Thomson profile complete of brackets and fixing bolts in stainless steel.