Biorefineries

Biorefineries, in short, are refineries that convert biomass into fuel or other byproducts that are beneficial in some way. Biomass is any organic matter used as fuel, or in this case, processed into fuel. These biorefineries can produce chemical materials by fractionating raw materials into intermediates, which allow them to be converted into products more easily.

Classification:

Biorefineries are classified by four features. The first one is the intermediate used between the raw materials and the finished product. Some of these intermediates include certain types of sugars or lignin. The second classification is the product produced by the biorefinery. These can be further classified into material or energy-driven biorefineries. Energy driven refineries focus on producing energy in the form of biofuel and material-driven refineries make bio-based products. The third category is feedstocks. Like products produced, there are only two main forms of feedstock, dedicated feedstocks and residues. Dedicated feedstocks are grown to be biofuels and to be used in a biorefinery. Residues are byproducts of other processes that happen to work as biofuel. The final classification is the method by which biorefineries transform biomass into a product. These methods include physical, where the chemical structure of the biomass is preserved, biochemical, which are processes under low temperatures that typically use microorganisms or enzymes, thermochemical, where the conditions applied to the feedstock are severe and highly stressful, and chemical processes wherein the biomass suffers change by a chemical. 

Environmental Impact:

One of the main goals of biorefinery is to contribute to a more sustainable world through reusing biological waste. Despite this, certain aspects of biorefineries do lead to environmental burdens. Feedstock is one of the biggest contributors to the environmental impacts of biorefineries. This contribution is related to the function feedstock has which is to grow, handle, and transport biomass. Agricultural residues are the feedstock with the lowest environmental impact although lignocellulosic crops and first-generation arable crops are also being used. However, environmental impacts are subject to change due to crop management practices, harvesting systems, or crop yields. 

Biorefineries are an environmentally great invention, and with so many varieties it is easy to see how they could be a modern source of fuel in a sustainable world. From using residues of other industries to, in general, using biological matter, biorefineries will be a staple of the future.

References

1. Qureshi, N. (2014) Biorefineries. Amsterdam: Elsevier Science. 

2. Jong, E. de et al. (no date) Bio-based Chemicals, International Energy Agency. Available at: Bio-based Chemicals  (Accessed: 28 January 2025). 

3. Gnansounou, E. and Pandey, A. (2017) Life-cycle assessment of Biorefineries. Amsterdam, Netherlands: Elsevier.