When Dutch chemist and inventor Jan Baptista Van Helmont first determined that decaying organic matter could result in flammable gases in the 17th century, little did he know how helpful this process, now known as Anaerobic Digestion, would be in combating food waste in the centuries to come!
The word ‘anaerobic’ means ‘in the absence of oxygen’. The AD technology mainly involves the decomposition of organic waste in a sealed oxygen-free digester tank to create bio-fertiliser and biogas.
While the biofertiliser is dense in nutrients and is an excellent alternative to fertilisers made from fossil fuels, biogas can be used as a fuel in a combined heat and power (CHP) unit to create renewable energy.
Moreover, a study by Poore and Nemecek found that 24% of food’s emissions come from food which is either lost in supply chains (15% owing to spoilage in processing and transport or lack of refrigeration) or wasted by customers (9%). This shows that food waste is responsible for around 6% of the global greenhouse gas emissions!
In other words, throwing away 3 kgs of edible food causes 23 kgs of carbon dioxide to be emitted into the atmosphere – which means if there is a way to eliminate food waste, we can do our environment a big favour!
No wonder, the AD technology has been recognised by organisations such as Friends of the Earth, the National Farmers Union, and even the UK government as one of the best ways to recycle food waste and to process farm and manufacturer waste.
Food waste in the food and drink industry: an overview
This particular industry is the UK’s largest manufacturing sector; it contributes £28.2bn to the economy each year, employing 400,000 people.
The post-farm-gate food and drink sector, specifically, generates a massive 9.5 million tonnes of food waste every year, costing £19 billion a year and producing 25 million tonnes of greenhouse gas emissions. An estimated 70% of this is edible waste that was still fit for consumption at the time of being discarded.
The frozen products and ready-to-eat meals sector alone accounts for 12% of total food waste in the good and drink industry, mostly because of the packaging. Other causes of food waste include production errors, discarded trimmings and inaccurate demand forecasting.
COVID-19 caused an immediate impact on the industry. Restaurants, pubs and cafes all closed for several months. Supermarkets, although open, saw empty shelves and disrupted supply chains. There was a massive decrease in “on-the-go” foodstuffs such as prepared wraps and sandwiches, and pasta and pizza-ready meals.
And let us not forget the extra 503 million meals being cooked and eaten at home every week. Food producers felt the strain too. Fresh produce struggled to make it out of the warehouses and into supermarkets due to the lockdown.
All of this has led to an increase in food waste. So how can AD technology help in eliminating the wastage? Let’s find out:
Benefits of using Anaerobic Digestion to combat food waste
Farmers, food manufacturers and food suppliers are increasingly turning to Anaerobic Digestion of food waste as the best solution to the waste disposal question and a positive step towards being more environmentally responsible.
1. Onsite energy generation
Biogas is produced in the process of Anaerobic Digestion of food waste. It is rich in methane and can be converted into renewable energy (heat, cooling and electricity) for onsite usage, or into biomethane for use as a vehicle fuel. This lessens the food producer’s dependency on fossil fuels, leading to saved costs and less air pollution. This also helps to capture methane gas that would otherwise have escaped into the atmosphere and contributed to global warming.
2. Valuable fertiliser
The semi-solid residue left behind after the digestion process – known as digestate – is an excellent fertiliser. It is rich in nutrients and is easier for plants to process than raw manure, making it not only more sustainable than chemical fertilisers but also more efficient.
3. Improved hygiene
Accumulated food waste can be challenging to dispose of and also lead to contamination and poor hygiene problems on the business premises. With Anaerobic Digestion, food waste can be easily disposed of in its entirety without the hassle of segregation. It also reduces the need for waste to accumulate, as even smaller quantities can be fed into the digester.
4. Economic opportunities
Anaerobic Digestion is in itself a business that employs multiple groups of people. There are contractors to handle the setup and maintenance of the digester, operators to keep it running and technicians to convert the by-products of Anaerobic Digestion into renewable energy and fertiliser.
This also presents an opportunity for food producers and farmers to make extra revenue through the sale of organic nutrients to other agricultural and horticultural customers.
Summing it up
AD is considered as the “best option” for sustainable food waste management in the UK, and it is expected to supply 15% of its energy from renewable sources by the end of 2020. By deploying this innovative technology via our iD-R-5K Compact Anaerobic Digestion system, businesses in the food and drink sector can convert their food waste into renewable energy which they can use themselves and generate revenue, sustainably and ethically. Contact us to find out more about our systems in detail.
