The use of biofuel has been on the rise, and companies are developing techniques to produce clean energy. One way that organizations are producing biofuels is through torrefaction. This process involves using simple materials such as grass, wood biomass, rice husks, sawmill, and straw to produce coal-like pellets.
The process requires heating these materials under high temperatures to turn them into pellets. In some instances, these pellets can be used with coal in large-scale combustion processes or on their own in small-scale combustion processes. Here are the challenges and opportunities of torrefaction technology.
To help you better understand the opportunities and challenges, have a look at how torrefaction works and why it’s important.
How Torrefaction Works
Torrefaction technology involves burning biomass such as wood, peat, and straw in a non-oxidizing state. Therefore, the temperatures must be high, usually between 200 – 300 °C. During this process, the biomass fuel becomes hydrophobic and can’t absorb water even when stored. Additionally, the weight reduces but the combustion heat increases.
Why it’s Important
Torrefaction has come at a time when the world needs friendlier energy sources. Therefore it’s a crucial process to realize this objective. This process turns these low-heat materials into viable energy sources with high heat. It also solves the transportation and storage paradox because the end product is easier to transport and store since it doesn’t occupy much space compared to the low materials.
Torrefaction has various opportunities. It can be used as a coal alternative in combustion processes. The process produces pellets that have similar energy levels to coal. However, these pellets produce fewer impurities than coal and hence are preferable.
The process is handy in places that use liquefied petroleum gas. This is because some materials, such as wood powder fuel, work like LPG after it’s compressed and ground into powder and compressed.
In addition, this process is economical and thus suitable for large-scale use with coal. Therefore it can produce biomass that works with coal to reduce harmful emissions. Additionally, this biomass is easy to handle and store, reducing handling costs. Moreover, it produces biomass with varying lower heating values (LHVs), which makes it easy to use in furnaces. However, it can’t replace coal completely because its LHV is still lower than 25 GJ/ ton.
Also, torrefaction can be comfortably applied in decentralized residential heating. However, the transport strategy might make it more expensive than other energy sources.
The main challenge with torrefaction remains how to deal with the emissions to make it a 100% clean energy source. Although torrefaction technology consultants have suggested methods of getting rid of these gaseous products, none have proven economical.
The cost of torrefied products is also high, making it uneconomical for residential use. Torrefaction is a crucial process in reducing the use of inorganic energy sources. This process involves burning materials such as wood, grass, and straw to produce coal-like pellets. These pellets have reduced exclusive coal use because they can be used for large-scale combustion together with coal-reducing impurities. The main challenge of this technology is the lack of a proper way to deal with resulting emissions to make it 100% clean.