CharcoalIn 2017 655 thousand tonnes of charcoal was imported into the EU from around the world. Large quantities of this come from the forests of tropical countries, such as Indonesia and Nigeria. Between them these two countries export 173 thousand tonnes of charcoal to the EU each year.
Why do you want to produce charcoal?
Managers of nature reserves often burn their plant cuttings onsite, as there is no buyer willing to take it away. This is because it has a low value as firewood, so is not worth transporting away. At the same time a lot of imported charcoal is low quality. In some cases producers have to add petrochemicals to make it burn. Therefore there is a gap many local markets for high quality sustainable charcoal.
What did you do in CANAPE?
CANAPE has tested a mobile charcoal burners (known as a retort) in wetlands. These tests were led by Broads Authority, in partnership with local landowners. This has demonstrated that there is indeed a market for locally produced high quality charcoal, and that this is seen as a premium product by local buyers. The Charcoal we are able to produce is of extremely good quality, burning extremely well and cleanly.
How does the production process work?
The charcoal is produced in a device called a retort. The retort is a large barrel shaped burner, which converts wood and plant material to charcoal using a processed called pyrolysis. In this process the wood is heated in a low oxygen atmosphere. This causes its structure to breakdown, whilst the lack of oxygen prevents it burning. As the material breaks down it releases hydrogen, which can then be burned to provide an ongoing source of heat for the process.
Exeter Retort in use in the CANAPE project. The steam is produced as the water in the feedstock evaporates. Once the wood has completed dried, pyrolysis can begin.
What products did you make?
Using this process charcoal can be produced from wood in 8 hours. This is in comparison to the 8 days required for production in a traditional earth charcoal mound.
Two biochar products were produced from conservation waste. Firstly ordinary charcoal for cooking that could be used as a high quality, local and sustainable substitute for BBQ charcoal.
Secondly a material known as biochar is produced. Biochar is a fine carbon powder that can be used for soil improvement. The addition of fine char to the soil provides a number of benefits to plant growth. It improves water retention, aeration and nutrient availability of the soil. The incorporation of biochar also stores carbon in the soil for long periods. Within the CANAPE project we trialled the production of biochar from reed.
1. Import figures sourced from Eurostat