Cellulosic Ethanol Feedstock Types
Biomass feedstocks that can be used for cellulosic ethanol production can be broadly divided into five categories:
1. Agricultural wastes — crop residues after taking the edible portion of the plant and can be in the form of stalks, leaves, trunks, branches, peels, or husks; all these parts of the plants are suitable as feedstock. In addition to this, edible agricultural products that are not suitable for human and animal consumption and rejected due to spoiling or contamination are also suitable as feedstock in the bioethanol production.
2. Forestry residue — logging and mill residues such as wood chips, sawdust, and pulping liquor.
3. Grasses — hardy, fast-growing grasses such as switch — grass grown specifically for ethanol production.
4. Trees — fast-growing trees such as poplar and willow grown specifically for ethanol production.
5. Municipal and other wastes — plant-derived wastes such as household garbage, paper products, paper pulp, and food-processing waste. Nevertheless, production of ethanol from starch — and sugar-containing food wastes requires first generation bioethanol technologies, which are in wide use in the current corn and sugarcane ethanol industries.