W11 Aerobic Digester Didactic Equipment Vocational Training Equipment Water Treatment Trainer
DESCRIPTION Waste water is drawn from a floor-standing feed tank (not supplied) by a DC motor-driven peristaltic pump. Rotational speed – and thus flow rate – is accurately set by a ten-turn potentiometer. The pump delivers the feed to the reactor vessel through a transparent lid. Air is supplied at a measured rate by a small compressor, and discharges into the base of the reactor via a spider-arm dispenser. This design prevents blockages and produces sufficient bubbling for stirring and reaction. The liquid level in the reactor is maintained at a constant value of five to ten litres, by an adjustable overflow device connected to the outer annular chamber of the vessel. Discharge is by gravity to a floor-standing product tank (not supplied). The reactor temperature is maintained by a three-term controller, which varies power to an immersion heater within the vessel. Any temperature between ambient and +35°C may be selected, the best conditions being a few degrees above the diurnal maximum in the user’s laboratory. Dissolved oxygen and pH probes and meters are included. The reactor lid contains a gas exit port, suitable for sampling the gases for subsequent analysis.
TECHNICAL SPECIFICATIONS Feed pump: 24V DC, peristaltic, 0-30rpm corresponding to 0-40 L/day Air compressor: 120V/240V, 0-3.0 L/min (STP) Reactor vessel: 10L maximum capacity pH meter range: 0.00 to 14.00 DO meter range: 0-100% saturation, resolution: 2% Reactor heater: Toughened glass, electrical immersion 200W Temperature controller: 3-term PID (temperature limit set at 35°C)