Devondale-Murray Goulburn Co-operative Co. Limited (MG) is Australia’s largest dairy food company. Popular brands include Devondale and Liddells, which produce a variety of milk, cream, butter, spreads, yogurt, and cheese.

Challenge

Devondale-MG wanted to be a good corporate citizen. It recognized that environmental consciousness extended to its Leongatha processing operations. The dairy cooperative wanted to go beyond merely complying with formal government requirements. It was in the market for a treatment solution with a low carbon footprint that would allow it to treat high-strength, biodegradable, industrial wastewater.

Solution

Devondale-MG selected ADI Systems as the successful bidder of a design/build contract to provide wastewater treatment. ADI Systems’ scope of work for the project consisted of a dissolved air flotation (DAF) effluent equalization tank with mixing, a low-rate anaerobic digester (ADI-BVF® reactor), and two aerobic ADI® sequencing batch reactors (SBRs).

A portion of the process plant’s wastewater is sent directly to the existing DAF; its equalized effluent provides the carbon source necessary for denitrification in the SBRs. The SBRs also treat the anaerobic reactor’s effluent. Excess biosolids (waste activated sludge) from each SBR is pumped to the BVF® reactor, where it is anaerobically digested.

Jet aeration (600 kW installed) supplies air to the two SBR basins, and two ADI Systems decanters in each SBR are used to remove treated effluent.​

The design raw wastewater characteristics include chemical oxygen demand (COD) of 6,500 ppm; biochemical oxygen demand (BOD) of 4,000 ppm; total suspended solids (TSS) of 1,300 ppm; fat, oil, and grease (FOG) of 500 ppm; and total nitrogen (TN) of over 300 ppm.

Results

The work ADI Systems did for Devondale-MG was essential to ensure that MG’s wastewater is properly treated in order to comply with Victoria’s Environment Protection Authority (EPA) standards. The wastewater treatment solution provides a very high quality effluent that is discharged into the local water authority works. Operating effluent characteristics are COD = 58 ppm; BOD = 4 ppm; TSS = 13 ppm; TN = 14 ppm, which easily meet permitted discharge limits.

By selecting ADI Systems for this wastewater treatment project, the dairy cooperative has ensured that its milk processing operations can be sustained well into the future, as well as maintain its “beyond compliance” goals in terms of environmental impact.