A guided tour of an Oxfordshire food waste plant

With that in mind, we took a trip down to a food recycling plant in Wallingford earlier this week.

We wanted to see what happens to your food waste if you do what you’re told and leave it to be collected by your district or city councils.

The food dealt with at that plant mostly comes from South Oxfordshire and Vale of White Horse District Councils.

It is run by Oxfordshire-based company Agrivert, which also uses food waste from Oxford City and West Oxfordshire District Councils at its plant near Yarnton.

As part of an innovative process, all the product is vital to a long process, which takes about three months.

The old food is eventually used as a liquid fertiliser called digestate – mostly on farms around Oxfordshire.

And the biogas produced by the product is converted into electricity in gas engines and then fed into the National Grid. Amazingly – when you think this was just old food people didn’t want or need about three months earlier – the power created by the plant in Wallingford is enough to power 4,800 homes.

But let’s go from the start of the trip.

We arrived, along with Becky Kenton-Lake, from the county council’s waste recycling team, for a special tour.

Our first stop was a huge chamber where the food is firstly dumped by lorries into (for want of a better term) a huge hole.

We saw as a lorry driver arriving with waste from Buckinghamshire backed his lorry in the huge hangar.

Within seconds, 26 tonnes of unwanted waste (soon to become energy gold) came streaming from the back of it. The stream was steady, then became an avalanche, before a strange mist – hopefully dust – descended on us.

The smell was odd. It was unpleasant, as anyone would expect, but perhaps unsurprisingly, it was something I’ve not really come across before.

The food dumped was mostly contained in plastic bags but bread bags and other paper bags had been used too. Councils and Agrivert have encouraged people to use other bags to ensure food is delivered, rather than simply chucked into the normal food waste collection.

After all, it is two and a half times cheaper to process food waste if it is put into a food waste caddy for recycling or composting than if it is chucked in the general rubbish.

From what I could see, most of it consisted of loaded bags and uneaten fruit. There were so many apples. There was debate between me and our photographer, Ed, whether someone had thrown a tealight into their waste and it had somehow lit as it came tumbling down from the truck but we came to the conclusion it was probably some sort of shiny foil glimmering in the light.

That waste will have then been macerated using great metal drivers pummelling it into a fine liquid. The bags which once contained the food would be diverted into another section, fired out later and cleared into a corner of the warehouse.

From there, the waste will have been pasteurised and then pumped into larger sealed tanks. It will then be stored until it is eventually taken away in tankers as the fertiliser.

The process can be compared to a large stomach. It must be biologically controlled to make a good product – both for gas and the fertiliser. Just three members of staff are needed to run the whole site in Wallingford but they have to respond to things going awry quickly, sometimes in the middle of the night.

The operation is worthwhile and helps the environment. Aside from the electricity produced, the fertiliser is used on 2,500 acres of farmland a year, replacing other, more harmful fossil fuel fertilisers.

This week, the county council is concerned more than any other week that pumpkins might be throw into general waste rather than placed into food waste.

I suspect some people will follow councils’ advice – and the food dumped from lorries will probably be loaded with pumpkins next week – but the county council wanted to remind residents.

Becky Kenton-Lake said: “18,000 tonnes of pumpkin were thrown into landfill across the UK in 2013.

“In Oxfordshire in 2017, we dealt with around five per cent more food waste during October and November, compared to September.

“Yet, with a bit of thought and creativity, pumpkins can have a useful life beyond Halloween. There are so many healthy and ‘green’ alternatives to throwing them away.

“You can make delicious soups, curries, cakes and even pumpkin brownies. Make sure you visit the Pumpkin Festival Good Food Oxford website for recipes.

“If you do decide to dispose of your pumpkins, remember to put them in your food recycling bin. As we’ve seen, on the tour of the Wallingford anaerobic digestion facility, pumpkins and other food waste can be recycled and used for future uses, such as electricity, and fertiliser for local farm land.”

So if you have pumpkins hanging around and don’t want them anymore, you have been reminded.

Residents are invited to go on tours of Agrivert’s facility and see what work is done at them. Others were taking place at the Cassington plant this week.

For more information visit www.agrivert.co.uk