Supply Chain Waste Prevention Guide 2013 - from factory in-gate to till

What’s it all about?

In vessel composting is a biological process which uses naturally occurring micro-organisms in the presence of oxygen to process waste food and other biodegradable wastes into nutrient rich, solid stabilised soil conditioners (compost). There are a variety of different technologies employed in the UK referred to as in vessel composting falling into 5 broad categories: Containers, Silos, Agitated Bays, Tunnels and Enclosed halls.

By managing the composting process within an enclosed area or vessel we have greater control over conditions, processing time is reduced and higher temperatures can be achieved making many facilities suitable for category 3 animal by products. The process generates its own heat so is self sustaining once begun.

The Good Stuff

• The process diverts food waste away from landfill, reducing methane emissions.
• The process produces good quality soil conditioners suitable for agricultural use which can replace nitrogen and peat based fertilisers.
• The technology is saleable from small farms up to large centralised treatment facilities making it very flexible.

Not so Good

• Capacity - Transport distances in the short term may be prohibitive but will improve as commercial capacity increases.
• Composting does not produce renewable energy but can still make a valuable contribution towards a low carbon economy.
• Not many facilities can process packaged waste so it is important to make sure the waste you have is suitable for the available process.

The composting process

Top Tips

• As with all waste destinations ensure you check the credentials of the location, including all permits, consents or exemptions are in place
• As mentioned in the drawbacks be sure to weigh up the costs/efficiency of de-packaging before sending for composting as this could impact your benefits

Frequently Asked Questions

Q: Is there any food, which cannot be composted?

A: Food which has been cooked - cooked food, even vegetables, can attract vermin

• Meat or fish
• Dairy products
• Non-food items such as cat or dog litter, large pieces of wood, coal ash
• Plastics and metals.

Although food waste is organic and will generally decompose, when mixed with other materials and put into landfill food waste can contribute to the production and release of harmful gases which potentially cause environmental damage.

However, by composting your food waste, you can actually use it to put goodness back into the earth. Composting is when waste decomposes to make compost. You can use this nutrient-rich compost in your garden.