Major Process Components: Headworks, Sequencing Batch Reactor
(SBR), Effluent Equalization, Sludge Digestion, Filtration, PLC
Napier-Reid Services: Process Design, Instrumentation & Control Design, Electro-mechanical
Supplies, Installation and Commissioning Support, Operator's Training
Scope of Supply:
- Mechanical: SBR Tanks (02 Nos): Decanter Assemblies - Napier-Reid
SD-3000, Fine Bubble Aeration Systems, Submersible Waste Sludge Pumps, Fittings,
and Valves with electrical actuators.
Effluent Equalization Tank: Submersible Transfer Pumps, Fittings, Valves.
Aerobic Sludge Digestion Tanks: Fine Bubble Aeration System, Telescopic Supernatant Decant Assembly, Submersible Sludge Transfer Pumps, Fittings
Blower Assemblies for SBR and Sludge Digestion Tanks including Motors and Accessories.
Alum Feed System: Alum Day Tank (1400 Litres), Metering Pumps, Valves and Tubings.
Instrumentation & Control:
Control Panel Complete with PLC, Main Disconnect, Fusing, Relays with bases, Wiring Terminals, Operator Interface Panel, PLC and Operator Int-erface Programming.
SCADA System: Pentium 4 Processor, Hard Drive, Dial-Up Modem, 19" LCD Color Monitor, Color Printer, Hard Drive for Data Backup.
Float Level Switch, Dissolved Oxygen and Suspended Solids Monitoring System.
Ultrasonic Level Sensors.
Distinguished Features: Napier-Reid's Decanter Assemblies
- Napier-Reid SD-3000, High Quality Effluent, Smaller Footprints, Remote Control,
- Process Description
SBR is an aerobic biological system comprising
a batch reactor for eliminating pollutants i.e. BOD, COD, TSS, nitrogen and phosphorous.
Bio-BatchTM is the SBR designed by Napier-Reid. It is a true interrupted batch feed
process, in which, continuous inflow is accommodated through an alternating fill
and draw by feeding two or more reactors. A unique feature of the Bio-BatchTM is
that there is no return activated sludge (RAS) or secondary clarifier required for
solids separation because both aeration and settling occurs in the same reactor.
A portion of the sludge is removed from the reactor at a predetermined interval
in each cycle to maintain a constant and calculated inventory of activated sludge
The Bio-BatchTM process is a sequence of five steps; fill / aerate, settle,
decant, idle / fill, carried out in a 4 hour cycle.
Fill / Aerate: Screened and de-gritted raw wastewater is mixed and aerated to satisfy the design oxygen demand.
In this step, BOD removal and nitrification takes place. To increase biological
performance and eliminate the conditions encouraging filamentous bacteria proliferations,
the inlet end of the reactor has a selector zone.
Settling: Following aeration, the air is shut off and flow is diverted to other reactor(s). A tranquil condition
is created in the main aeration zone for efficient sludge settling. During this
period anoxic/anaerobic conditions are created for denitrification and biological
Decant: After settling, the clarified supernatant water is
decanted through swing type or telescopic type decanter for further processing to meet the discharge standards.
Fill / Idle: At reduced loadings an idle sequence
can be introduced and added to the treatment cycle. When the system is designed
for nutrient removal, idle time can also be used during the aeration sequence to
create an anoxic/anaerobic condition for denitrification and biological phosphorus
BOD5: 250 mg/L
Suspended Solids: 390 mg/L
TKN: 35 mg/L
TP: 9 mg/L
Temperature: no less than 7oC
Specified Treated Effluent
BOD5: 10 mg/L
TSS: 15 mg/L
July to October: 3 mg/L
November to June:
TP: 1 mg/L