As the recycling lorry trundles off into the distance laden down with you and your neighbours’ food waste do you ever wonder where exactly it is headed and what will become of your leftovers?
And do you ever question whether the effort of sorting and separating organic waste from the regular rubbish is really worth it? Well, the answer to this is a categorical yes – food that ends up in landfill sites rots and lets off methane which is a damaging greenhouse gas.
Obviously, the most important message is that we all need to throw away less food; throwing good food away is a waste of the energy, water and packaging used in its production, transportation and storage. According to recyclenow (England’s national recycling campaign funded and supported by the Government), if everyone stopped wasting food which could have been eaten, it would have the same CO₂ impact as taking 1 in 4 cars off UK roads.
In addition to the environmental damage it is estimated that wasting food costs the average family with children almost £60 a month – or over £700 a year. About seven million tonnes of food is thrown away by households in the UK every year – most of which could have been eaten.
But no matter how careful households are there will always be some food waste in which case recycling is definitely the answer to how it should be disposed of responsibly. What happens though to the contents of your food recycling bin after collection? Individual councils recycle food waste in different ways but the two most common processes are:
In-vessel composting – this is where the food waste is mixed with garden waste. The two are shredded and then composted in an enclosed environment for between two and four weeks. The composting is done at temperatures of up to 70⁰C to speed up the process and kill off any harmful microbes. Afterwards the material is moved outdoors where it is left to mature for one to three months before being used as soil conditioner.
Anaerobic digestion – this process uses micro-organisms to break down food waste and other organic waste in an enclosed environment. As there is no oxygen present methane is created. Methane is a harmful greenhouse gas which damages the Earth’s atmosphere but in the recycling process it is safely collected and converted into biogas which is used to generate electricity, heat or transport fuel. It also creates a nutrient-rich digestate that can be used as a fertiliser for agriculture or in land regeneration.
Rather than sending food waste away to be recycled many householders now do their own composting. Doing so for one year can save global warming gases equivalent to all the CO₂ a kettle produces annually or a washing machine produces in three months. And of course the end result is a nutrient-rich compost for the garden.
So when it comes to food waste the recycling message is as relevant as it is for every other form of recycling – reduce, re-use, recycle.