Background
Northwich Waste Water Treatment Works had difficulty achieving their solids compliance of below 45mg/l and required a temporary solution to prevent non compliance’s in future. During periods of dry weather the site struggled with solids compliance which were averaging 40mg/l but could peak at 82mg/l.
The crude sewage was highly alkaline which added to the solids being slow settling in nature.
The Overall Objective
The overall objective was to reduce the Total Suspended Solids content however United Utilities also wanted to reduce the Phosphorus and Iron concentrations with chemical dosing, due to an upcoming Phosphorus limit being introduced.
Solution
SPS supplied and installed a D100 DAF with and integral sludge pump and walkways to ensure United Utilities were achieving their discharge consent.