Australian farmer-owned dairy cooperative Norco Foods continues to receive good results from Gold Coast City Council’s (GCCC) testing at its Aerofloat wastewater treatment plant.
Recent testing at the site shows that the Aerofloat design is continuing to reduce the chemical oxygen demand (COD), total suspended solid (TSS), and oil and grease (O&G) levels in the wastewater well below the GCC discharge standards.
Aerofloat’s design at Norco consists of two AeroDAF 400s as the first stage to remove most of the milk fat and protein (by removing the majority of the TSS and O&G). This is followed by a biological stage — the Moving Bed Biofilm Reactor (MBBR) — for approximately 50% of the flow, to further reduce the COD (soluble protein and lactose). The final stage in the AeroDAF 200 removes any remaining biological solids from the MBBR.
Aerofloat’s Managing Director, Ray Anderson, said, “We are producing excellent primary effluent from the two AeroDAF 400s. This has created a stable environment for the fixed film biological culture in the MBBR.”
GCCC discharge limits are 1500 mg/L for COD, 600 mg/L for TSS and 200 mg/L for the O&G. The Aerofloat design at Norco is consistently achieving an effluent quality less than 900 mg/L of COD, 200 mg/L of TSS and 25 mg/L of O&G, meeting regulations.