To increase the sustainability of biofuels, there is currently a drive to turn away from deriving them from food crops, such as corn and sugarcane. Bioethanol derived from the waste products of agriculture and the food chain is more attractive as this avoids competition with food crops, reduces food waste and lowers the carbon footprint. Achieving this on a commercial scale needs to overcome a number of hurdles, which the Biorefinery Centre on the Norwich Research Park working on.
Sugars are the starting point for the production of bioethanol, and are readily obtainable in large quantities from food crops such as sugar beet, corn and wheat. In agri-food waste however the sugars are effectively locked away in the structure of the plant material – mostly in the form of lignocellulose. Lignocellulose gives plant cells walls their rigidity and resistance, but this makes them harder to convert into biofuels. For most agri-food waste a pre-treatment is needed to break open these structures, reducing the overall economic viability of the process.
However waste paper, particularly shredded paper that cannot be recycled, has effectively been pre-treated, with much of the lignocellulosic structure broken down.
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