Anaerobic digestion
Anaerobic digestion (AD) is a process that uses microorganisms to break down organic waste such as food waste, farm waste, and certain categories of animal byproducts. The process generates renewable energy and biofertiliser, making it very environmentally friendly.
How do anaerobic digestion facilities work?
Anaerobic digestion plants use a multi-step process to break organic matter down into a biofertiliser and renewable biogas. Here’s how the anaerobic digestion process works.
Key benefits of anaerobic digestion
Microorganisms save energy
Using anaerobic digestion for food waste recycling can help you reduce Scope 3 emissions. Anaerobic digestion is a low-carbon, biological process that doesn’t require light or oxygen, keeping emissions low.
Suitable for many types of organic waste
Anaerobic digestion facilities can accept many types of organic waste. There are exceptions, such as items that would “upset” the chemical or microbial balance of the digester. Let us know what you have, and we’ll advise.
AD plants create biofertiliser and biogas
When the anaerobic digestion process has broken down your food waste and organic matter, the resulting liquid can be used as a nutrient-dense biofertiliser, and the gas released is captured as renewable biogas.
Anaerobic digestion of food waste at AD plants
Simpler recycling regulations in England, the Waste (Scotland) Regulations, and the Waste Separation Requirements (Wales) each compel businesses to have a separate collection for food waste.
If your organisation generates a significant volume of food waste, AD plants are a great option. If you need a reliable supplier for food waste disposal, we can help. Shred Station will arrange your food waste collections, ensuring all possible material is put to good use at an anaerobic digestion facility.
Get in touch
Get in touch to ask any questions or get a quote for anaerobic digestion services.
Frequently asked questions
If your query isn’t answered on this page, feel free to give us a call on 0800 035 3395 or visit our FAQs page for more frequently asked questions.
Many types of waste can be processed for anaerobic digestion. We accept packaged food, expired food, fruit, vegetables, bakery waste, meat, dairy, beverages, farm and agricultural waste, and also waste leftover from food processing or manufacturing (e.g. peels and pomaces). There are some foods that can’t be sent for anaerobic digestion. Let us know what you have, and we can advise.
Yes, we can accept packaged food.
Anaerobic digestion creates two byproducts.
The first is an organic fertiliser called digestate. Essentially, this is what’s left when the AD facility’s microorganisms have broken down all of the food and organic waste. Digestate is reused in the agricultural sector to fertilise crops.
The second is biogas or biomethane. This gas is captured by the AD plants and fed back into the grid as a renewable form of energy.
Biogas is a renewable gas that is produced when organic waste, such as food, breaks down in an oxygen-free environment. It is one of the key environmental benefits of having organic waste recycled at anaerobic digestion plants.
Digestate is the nutrient-rich substance left over when the microorganisms in AD plants have finished “eating” all of the organic waste in the digester. It often takes the form of a sludge or slurry and can be further separated to create a liquid fertiliser and a solid fibrous material similar to compost.
Anaerobic digestion breaks down organic matter without oxygen in sealed tanks. It produces digestate fertiliser and biogas, and typically breaks materials down a lot faster than composting can.
Composting works by breaking down organic matter with the help of oxygen, naturally occurring bacteria, and fungi. It produces nutrient-dense compost, but it can take a while to break materials down, and the compost heaps have to be physically turned. This can be laborious and can also be quite smelly - not ideal for the surrounding neighbours!
Anaerobic digestion is generally seen as superior to composting because the process generates fewer emissions, yields green energy, and isn’t as odorous.