The plant is designed to treat up to 400m³/day of landfill
leachate from cells of varying maturities, to reduce the COD,
ammonia and nitrate concentration prior to sewer discharge.
Whitewater was retained by the Principal Contractor to provide
process design, equipment specification, oxygen transfer testing
and performance trial review.
The plant consists of an influent leachate holding tank, transfer
pumps, two 1500m³ SBRs and an effluent
holding tank all constructed in reinforced concrete. The SBRs
are covered to retain heat.
Denitrification takes place during anoxic filling and methanol
dosing is provided to supplement the leachate COD as required.
The anoxic stage is followed by aeration using fine bubble diffusers
with automatic control of the air blowers by dissolved oxygen
concentration. Automatic pH control is provided by caustic soda
A fully automatic sequence controller allows the operator to
set the number of anoxic fill and aeration stages before settlement
of the sludge and decanting under gravity into the effluent holding
tank. The treated effluent is held until a full analysis has
been carried out to ensure compliance prior to discharging to
sewer or road tanker.
Provision is included for future addition of tertiary treatment