Biosolids drying plant officially opened

On 16 January, the Victorian Minister for Water, the Hon Peter Walsh MLA, officially opened the $77 million biosolids thermal drying facility at the Black Rock environmental precinct in Connewarre - the largest biosolids drying plant of its type in the Southern Hemisphere.

The project has been more than 10 years in the making and will create 12 new jobs for the Geelong region while providing an environmentally friendly solution for managing waste by-products. Located adjacent to Barwon Water’s Black Rock water reclamation plant, the fully enclosed thermal drying facility will convert biosolids - a by-product of the sewage treatment process - into nutrient-rich farm fertiliser.

“The plant will treat up to 60,000 tonnes of biosolids a year and will significantly reduce greenhouse gas generation compared with alternative treatment methods,” Minister Walsh said.

“It is expected to reduce greenhouse gas emissions by 40% and cut heavy truck movements by 1000 a year, while largely reducing the land area required for biosolids processing.”

The Black Rock water reclamation plant is the Geelong region’s largest sewage treatment and water recycling facility and produces almost 140 tonnes of biosolids every day. Biosolids make valuable fertiliser, but must be first dried and turned into pellets.

An interim arrangement was reached in the late 1990s for Melbourne Water to transport the biosolids to the Western Treatment Plant in Werribee. Since then, nearly 500,000 tonnes of biosolids have been trucked to Werribee for drying before being transported for use as fertiliser.

A group of community members and industry professionals was convened in 2004 and determined criteria for a world-class treatment facility. The facility needed to:

• be fully enclosed;
• not omit odours beyond Barwon Water’s boundary;
• have a small environmental footprint;
• be sympathetic with the coastal landscape;
• produce a high-quality product.

The biosolids drying facility, which has been designed, built and operated by Water Infrastructure Group as part of the Plenary Environment consortium, meets all these criteria. It receives wet biosolids via a pipeline from the nearby water reclamation plant and by truck from Barwon Water’s other reclamation plants. They are then dried and pelletised via a natural-gas-fuelled process before being made available as fertiliser.

The pellets meet the highest standards set by the Environment Protection Authority (EPA) and the plant process is cooled by recycled water from the Black Rock plant. That water is then returned to the Black Rock plant to be re-treated.

Peter Everist, Water Infrastructure Group General Manager, explained that the facility provides a sustainable solution for the next 20 years.

“Water Infrastructure Group brought a new thermal drying technology to Australia that hasn’t been seen here before. It is a high-tech plant that minimises energy use and emissions, and has a small footprint to minimise the scale and impact of the building,” said Everist.

“As part of Water Infrastructure Group’s design, build, operate and maintain approach, we’re always looking for new ways of doing things to provide better service to our clients and minimise costs. One of those is our virtual control room, which is the next generation of how we run plants. We’re implementing virtual control room technology at this plant and others in Australia at this moment.”

Sitting alongside the existing reclamation plant and the Class A recycled water plant (currently under construction), the facility completes the sewage treatment cycle.

“The completion of the project is an important step in Barwon Water’s long-term goal to have ‘no-waste’ sewerage systems where 100% of recycled water and biosolids are committed to sustainable use,” Minister Walsh said.

A short video about the launch of the plant can be viewed below.