Biochar is created through the process of pyrolysis. Pyrolysis produces three products, two of which, syngas and bio-oil, can be used as biofuels.
Biochar has significant potential for use in improving soil condition and in carbon storeage. Biochar can be added to soils to increase its fertility by retaining nutrients and water. It reduces greenhouse gas emissions from the biomass that would otherwise naturally decompose. The use of Biochar is a practice indigenous populations of the Amazon used thousands of years ago producing the Terra preta - the world’s most fertile and rich soil.
How is it made?
Biochar is created through the process of pyrolysis, a technique whereby organic matter is heated to at least 350°C under oxygen-depleted conditions.
Pyrolysis produces three products; the quantities of each are dictated by a number of factors such as the speed of the pyrolysis and temperature used.
- Biochar is the solid residue which can be added to soil. This is a stable storage form of carbon for hundreds to thousands of years.
- Bio-oil and syn-gas, which can be used for heating and electricity generation.
Advantages of Biochar
- If used as a soil enhancer reduces the need for fertiliser application and therefore the possible negative impacts of fertiliser use, manufacture and application; such as leaching into groundwater.
- Water retention - More nutrients stay in the soil instead of leaching into groundwater and adding to the production nitrous oxide and methane (greenhouse gases)
- It is a way to deal with biological wastes and produces a non-odorous and much more compact compound which does not release greenhouse gases into the atmosphere, in comparison to composting.