“Biostabilising” of organic waste in Scotland could produce less carbon than either landfilling or incinerating it, however, current operational challenges in collection and processing limit the potential of this technology, a new report from Zero Waste Scotland finds.
The report, Alternative Residual Waste Treatment: Biostabilisation, carried out by consultancy Ricardo on behalf of Zero Waste Scotland, is a study of alternative “residual” waste treatment practices across Europe.
Zero Waste Scotland describes “residual” waste as what currently goes to landfill and has not been reused or recycled.
Biostabilisation is the process whereby the organic matter in waste that goes to landfill is broken down in a controlled environment so that it will produce fewer harmful greenhouse gases when its landfilled – this requires a biological process, Zero Waste Scotland says.
The report also compares the carbon impacts of different methods of biostabilisation, namely dry anaerobic digestion followed by in-vessel composting, and in-vessel composting alone – both with and without the production of refuse-derived fuel (RDF) as part of the process.
It concludes that all three processes investigated result in a significantly lower carbon impact than either incineration or sending the untreated waste directly to landfill. It also finds however, there are some operational issues with the different biostabilisation methods.
Waste policy in Scotland is changing, with the ban on biodegradable waste to landfill coming in 2025.
Zero Waste Scotland intends for the report to be used as a tool for government, policymakers and local authorities looking to choose the best options for managing the waste they’re responsible for, as well as industry.
Commentating on the report, Chief Executive of Zero Waste Scotland, Iain Gulland, said: “Waste policy in Scotland is changing, with the ban on biodegradable waste to landfill coming in 2025.
“Zero Waste Scotland commissioned this research in order to help inform waste treatment choices by policymakers, local authorities and others, on how to handle their waste after this date. We also anticipate the findings being useful to industry.
“The study shows this is a complex area, with different requirements to be balanced, and a thorough understanding required of the impacts of the different technologies available, before choosing one.
“It does however further underline that we should be doing everything we can to reduce waste, then reuse and recycle, in order to absolutely minimise the amount of waste heading for landfill in Scotland.”
