A BIORULLI® rotating biological contactor (RBC) carries a pack of closely spaced polypropylene discs on a shaft turned slowly by a geared motor, at 1 to 5 rpm. The discs sit about 40% submerged, so each rotation exposes the surface in turn to the wastewater, from which micro-organisms take their nutrients, and to the oxygen in the air.
A biological film forms on the discs within 5 to 15 days of start-up. The process combines the strengths of activated sludge and trickling filters, and adapts itself to changes in flow and load without operator input.
BIORULLI® is a registered trade mark of MITA Water Technologies, who manufacture every component of the system in Italy.
The Series M is supplied as a packaged unit with its own basin and GRP cover, ready to install indoors or outdoors. No concrete foundations or support structure are needed, so a unit can be moved to another site if requirements change.
The Series B disc roller is a steel shaft carrying single-piece polypropylene sandwich discs, held together with hot-dip galvanised tie-rods, spokes and flanges. Units sit in trapezoidal or semicircular basins built in concrete or steel, and are laid out in series or in parallel to suit the flow, the influent BOD5 and the required effluent quality.
BIORULLI® units treat domestic sewage and highly polluted industrial wastewater. They can also be added upstream as roughing treatment, or downstream as secondary treatment, when the load on an existing biological plant increases or changes.
