FAQ

Sorting food waste

Why will sorting food waste become compulsory in the Brussels Region from 15 May 2023?

Because it is important to give food waste a new life, by turning it into green energy (gas, electricity, heat) or fertiliser that can be used to enrich vegetable gardens or agricultural land. The white bag is for waste that will go to an incinerator. Food waste that is placed in the orange bag or is composted will create resources!

What solutions are offered to Brussels households for sorting their food waste?

There are three complementary solutions:

• Food waste produced by households can be placed in an individual’s garden compost or indoor compost bin;
• Food waste can also be taken to one of 200 neighbourhood compost bins dotted around the region;
• Lastly, food waste can be sorted by using an orange bag: these bags will be collected once a week by Bruxelles-Propreté for recycling.

Orange bag

What waste can you put in your orange bag?

Almost any kind of kitchen waste can be placed in the orange bag: leftovers from meals (including meat and fish scraps), fruit and vegetable peelings, coffee grounds and teabags, food past its use-by date (without the packaging), and even kitchen roll. A few items should not be put in the orange bag (because they are less suitable for biomethanisation or composting): animal bones and carcasses, fish bones, eggshells, nutshells, the shells of oysters, mussels, fruit stones, etc. They must always be disposed of in the white bag. Liquid food waste (sauces, oils, soup leftovers, etc.) are not permitted in the orange bag.

Where can you get waste bags to sort your organic food waste?

The region’s orange bags, printed with ‘Bruxelles-Propreté’, are available from supermarkets. Only these waste bags are permitted for the collection of food waste.

Where is your food waste processed?

In a biomethanisation centre outside the Brussels-Capital Region, in Ypres (Ieper) or Herstal. Starting in 2026, the food waste from Brussels households will be recycled in a new biomethanisation plant located in the Brussels area. This will result in a short supply chain, giving a second life to these resources.

How is your food waste treated?

Food waste is recycled in a biomethanisation system followed by sub-tunnel composting. The biogas process involves grinding down organic waste, before macerating it with microorganisms in an oxygen-free anaerobic reactor, i.e. without oxygen. At the end of the process, we obtain biogas and digestate.

• Biogas is used to generate heat and electricity simultaneously
• The digestate, which is organic matter that has not broken down, will be recycled through composting.

The decomposing matter will remain in the reactors for around two to three weeks.

After methane is produced in the biomethanisation plant, the digestate, i.e. the remaining organic matter, undergoes an extra phase of maturation lasting two to six weeks. This creates a high-quality compost.

What if you already make compost at home? Can you participate in the collection of orange bags?

Of course you can! Organic food waste collection is complementary to composting. You can throw into your orange bag any waste that takes longer to break down into compost, e.g. citrus fruit, meat or fish leftovers, etc.

How can you avoid any unpleasant odours and small flies?

To avoid this inconvenience, you can for example wrap your waste in a brown paper bag, bread bag or newspaper. You can also seal your bag with a freezer bag clip or clothes peg.

Why keep orange bags in the small orange container?

This container is for collecting and storing several orange bags. It keeps the public space clean, even when there are wild animals around. Your food waste must be put into orange bags and these must be placed in the container. On collection day, you should put your container out in front of your home: any orange bags inside the container should be tightly closed.

What are the advantages of food waste collection?

• A lighter white bag: studies by Bruxelles-Propreté show that food waste makes up 40% of the weight of our white bags.
• The quantity of waste sent to the incinerator is thus reduced. Waste goes into the white bag. The orange bag is for resources that can be used to produce energy and compost.
• Depending on the method used, this waste treatment makes it possible to produce renewable energy and natural fertiliser for soils.
• Sorting food waste therefore helps to avoid the use of fossil fuels. It also avoids the use of chemical fertilisers, which are harmful for health and the environment.

What about people living in apartment blocks that have large containers?

If you live in an apartment block that has its own large containers – for white bags, paper-cardboard and PMD – Bruxelles-Propreté will have offered to install a large orange container with wheels. This has a capacity of 240 litres and is for food waste from everyone living in the apartment block. They should simply put their securely tied orange bags into this container.

Compost

What exactly is compost?

Compost is an organic soil improver that has the appearance and consistency of loose, almost black soil, with a pleasant, forest-floor scent. It results from a decomposition process in which various organic substances (of plant or animal origin) are converted by living organisms (fungi, bacteria, worms, woodlice, etc.) into a kind of humus, under controlled conditions of aeration and humidity.

Initially consisting of 97% organic matter, compost contains living organisms as well as mineral elements which pass into the water in the soil, where they feed the plants.

Where can you buy a vermi-compost bin?

There are several shops that sell individual composting equipment in Brussels. The prices vary from shop to shop. Brussels Environment has published a list of retailers of individual composting equipment. You can also easily build a vermi-compost bin yourself, by stacking buckets or bins. There are many tutorials on the web.

Where can you get a compost bin?

Brussels Environment has issued a special publication with a list of retailers that sell composting equipment.

See our specific FAQ.

Which municipalities offer grants for buying a compost bin?

The list of municipalities that offer their residents grants to buy a compost bin or vermi-compost bin can be obtained by following this link. Discounts of up to 75% are available when purchasing material: each municipality sets its maximum amount.

How do you make good compost successfully?

To make good compost in your garden, whatever the technique you use (except a vermi-compost bin), be sure to bear these 7 rules in mind. They will help you throughout the composting process

1. Start in the spring, summer or autumn. The composting process slows down in cold weather and the materials take longer to decompose.
2. Add organic material that is as fresh as possible to your compost bin. That way you can avoid problems with odour.
3. Do not add waste in large pieces. The smaller the pieces of organic matter that you add to your compost, the more quickly they will decompose.
4. Mix well. For optimal compost, it is crucial to ensure a balance (50/50) and a good mixture of green/wet matter (waste from food and the garden) and brown/dry matter (dead leaves, crushed material from branches, etc.).
5. Avoid adding large quantities all at once. In particular, if a single type of waste is to be composted (e.g. grass cuttings)
6. Ensure optimal aeration. Air flow is really crucial, to allow the organisms in the compost to do their work properly.
7. Be sure to maintain optimal moisture. The compost should be damp but not too much. By using a cover, you can control the addition of dampness.

How do you know if your compost is good?

Good compost is uniform, with a lovely dark colour and little recognisable matter in it. Wood, which decomposes slowly, is very often found in mature compost. It should be possible to crush any twigs you find in your compost with your fingers. If you find larger sticks, they should be easy to break. Mature compost should also be relatively dry, and aerated, with a pleasant forest floor scent.

What can you do with your compost?

The compost you have produced can be used to grow all kinds of plants: vegetables, perennials, the lawn, annual flowers, etc.

Finished, completely mature compost will be used for trees and bushes, as well as for mixtures for seed beds and flowerbeds, and for the lawn. It needs to be sieved before use. Large pieces that remain after sieving can be put back into the compost bin (e.g. with grass cuttings), where they will help to activate the compost.

 

What if you have not found the answer to your question?

See the FAQ at Worms, a non-profit organisation that works in organic waste management in Brussels.