DESCRIPTION
Aerobic Digester is designed as a comprehensive study facility of this biological water treatment process (continuous activated sludge process).
Synthetically prepared waste water may be used to gain a working knowledge of the operational parameters and purification efficiencies.
The equipment consists of a ten litre reactor vessel mounted on a base, with a liquid feed pump, air supply and instrumentation for monitoring and controlling the process.
The cylindrical wall of the reactor is made from a porous material to retain the suspended solids while allowing treated water to pass through to the outer, annular exit chamber. The porous liner is removable for cleaning; Waste water is drawn from a floor-standing feed tank. Rotational speed and thus flow rate are accurately set. Air is supplied at a measured rate by a small compressor, and discharges into the base of the reactor via a spider-arm dispenser, designed to prevent blockages as well as to produce sufficient bubbling for stirring and reaction.
The liquid level in the reactor is maintained at a constant value of 5-10 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. The reactor temperature is maintained by a controller which varies power to an immersion heater within the vessel. Any temperature between ambient and +35°C may be selected.
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.
