Unlock the energy potential of dairy sludge

In the treatment of wastewater from dairy processing, fats, oils and greases (FOGs) are removed from the waste stream.

The resulting white sludge is an energy-dense material containing ~ 50% of the COD of the wastewater. Yet white sludge is often disposed of via land spreading without the realisation of the energy potential.

Biowave™ pre-treatment transforms dairy FOG sludge into a viable feedstock for anaerobic digestion. Our treatment facilitates the break down of the long chain fatty acid content of FOGs sludge, which would otherwise inhibit AD.

Biowave™ unlocks the energy potential of FOG sludge, resulting in substantially higher biogas yields in AD and eliminating the need for costly disposal services.


Unlock the large energy potential of white sludge

Eliminate sludge disposal costs

Generate more biogas

Flexible, modular solution

Common Questions

Dairy fats, oils, and greases (FOGs) are a by-product of the processing of milk into dairy products. FOGs are removed via dissolved air flotation system (DAF) in the treatment of dairy wastewater. The DAF system removes suspended solids by introducing a stream of pressurized water saturated with dissolved air. The release of the trapped air into the influent stream essentially floats the suspended solids to the surface, where a beam skims them off. This is the white sludge.

White sludge is high in long chain fatty acids (LCFAs). The major LCFAs in dairy FOG waste are oleic and palmitic acid. These compounds are insoluble, inhibitive to anaerobic digestion, and will build up in a digester, continually reducing performance. However, FOGs are energy-dense and white sludge can represent > 50% of the total COD of the dairy wastewater. Accessing the COD for conversion to energy in AD means the LCFA content of the white sludge must be removed.

Application of Biowave pre-treatment to dairy FOGs reduces the LCFA content of the dairy FOG sludge. Oleic and palmitic acid reductions of up to 60% have been achieved with an increase in biogas yield in biomethane potential assays of Biowave treated white sludge.
Using Biowave™ pre-treatment to break down the LCFAs from dairy waste creates a product that is no longer harmful to anaerobic digestion and allows the microorganisms to access this untapped energy – leading to a substantial increase in biogas.

The land spreading of dairy processing sludges is expected to be increasingly restricted, with limited availability of land, raising costs of disposal. Biowave™ eliminates these costs and closes the loop in the circular economy, diverting a valuable resource from disposal and using it to create renewable energy.