Turning trade waste to energy

Trade waste can include contaminants that can be harmful if washed down the drain without proper treatment. A project being undertaken at RMIT, however, is investigating how trade waste can be used for nutrient or energy recovery.

Known as trade waste, liquid wastewater from a food business or industrial entity sometimes needs to be treated before it is discharged. This is to protect the sewer system from any harmful chemicals or fats that may be washed down the drain from commercial businesses, including water that is used for the preparation or cooking of food, washing dishes or cleaning. The liquid waste often has a high nutrient load and the occasional presence of contaminants that can cause harm.

A wastewater PhD research project being delivered by RMIT University and City West Water is focusing on recovering resources and energy from trade waste. The project aims to find ways for City West Water trade waste customers to reduce the cost that is often associated with the disposal of organise waste streams, using them instead for nutrient or energy recovery.

An added benefit of the energy recovery aspect of the project is that it could reduce greenhouse gas emissions as part of City West Water’s Emissions Reduction Target commitment to reduce emissions by 80% before 2025.

RMIT PhD student Jake Elliot is leading the research. Elliot has a double degree in Chemical Engineering and Biotechnology, and three years’ experience working on trade waste treatment systems.

According to Rachel Meinig, Senior Renewable Futures Engineer at City West Water, the project will ultimately help in providing advice and guidance to customers around resource recovery.

“The aim of this project is to create a system for classifying trade waste based on its chemical properties, to easily identify which effluent has potential for resource recovery,” she said.

The project is great hands-on relevant experience for students.

“Industry-university partnerships such as this provide a great opportunity to PhD students like Jake to undertake research directly addressing industry needs, working alongside industry and gaining vital experience,” said RMIT Distinguished Professor Andy Ball, Director of the Australian Research Council Training Centre for the Transformation of Australia’s Biosolids Resource.

“The research carried out by Jake will examine both the biological and technical cycling of waste organics and will assist trade waste customers to move towards a circular economy.”

The research is targeted towards investigating the potential for nutrient recovery and biogas, a renewable energy source that can produce both energy and heat. The nutrients recovered from the wastewater can be re-used as fertiliser.

The project will continue through to the end of 2023.