Nestlé’s factory in Fawdon has achieved zero waste to landfill by turning waste from the confectionery site’s manufacturing processes into renewable energy and clean water through anaerobic digestion (AD).
Every day, up to four tonnes of solid waste residues – a mixture of rejected chocolates and sweets, along with leftover residues of starch and sugar – are broken down and partially dissolved using 200,000 litres of liquid waste from the site’s cleaning processes to create a ‘chocolate soup’. This is fed into an oxygen-free AD tank, where bacteria breaks down the biodegradable material and converts it into by-products such as biogas, which is used to meet 5–8% of the site’s energy needs.
As well as generating renewable energy, the water discharged from the factory is now virtually clean.
