A major contributor to GHG and climate change is food waste. If food waste were a country, it would be the third highest emitter of GHG following China and the USA.
Scotland is championing some innovative campaigns that have been set up to address the issues surrounding food wastage. SEPA and Zero Waste Scotland have established campaigns that aim to raise awareness amongst businesses and households on food waste and promote efficiencies to maximise food usage. In November 2016, Zero Waste Scotland published a report estimating that 1.35 million tonnes of food and drink – equivalent to more than eight million elephants – is wasted in Scotland every year. Zero Waste Scotland further illustrated that 380,000 tonnes (60 per cent) of household food waste would have been avoidable if purchases been planned, or food stored or prepared differently.
Nevertheless, we know that some food waste is inevitable for example bones or banana and orange peel. This kind of food waste could be efficiently re-used or recycled if it is not mixed with other waste that would lead to them being sent to landfill.
Currently, the most capable way to recycle food waste is using anaerobic digestion, the breakdown of food waste by microorganisms in an airtight condition to produce biogas and bio-solids. The biogas is used to generate clean energy while the bio-solids are used to enrich the soil.
However, in the UK, it is currently assumed that this process is only safe and economically viable on a large scale. Food waste, therefore, needs to be collected from different locations and brought to the large anaerobic digesters to be recycled. This process is perceived to be counter-productive, though. The level of decay that would occur during storage and transportation would result in a reduced yield from the anaerobic digesters. In addition, the carbon dioxide emission by trucks during transportation of food waste poses a huge environmental concern.
As well as inefficiencies in the process, we also need to change people’s food disposal habits. It was observed by a Mintel report that there was only a marginal increment in food waste recycling in the UK from 43.5 to 43.7 per cent between 2014 and 2015.
We need to re-think food waste recycling if Scotland is to meet the target to ban food waste disposal in landfill/sewer by 2020. There is a need to develop a more novel, robust, compact and safe anaerobic food waste digestion system that could enable household recycling of food waste.
Individuals will directly benefit from the recycling process in the form of clean energy hopefully enhancing their commitment to recycling not just their food waste but other waste streams such as plastics that will not be contaminated with putrid and decaying food waste.
Ifeyinwa Kanu is a PhD Researcher at Heriot Watt University, Director of IntelliDigest Limited.