Biofuel Residues/Wastes: Ban or Boon?

Abstract

Biofuel production generates significant amounts of low-value residues and wastes. This results in concern over the sustainability of the biofuel industry and its impact on the environment. Bioconversion offers opportunities for the economic utilization of biofuel residues and wastes with concomitant remediation of wastes. Due to their characteristics, these residues/wastes can serve as low-cost substrates for bioconversion to high-value products. Attempts have been made to produce several bio-based products, such as single-cell proteins, single-cell oil, enzymes, bioplastics, and organic acids. The authors review biofuel residues/wastes generation and their use in value-added processing. In addition, special attention is given to economic analyses of value-added processing of biofuel residues.

KEY WORDS:

• bio-based products
• biofuel
• biofuel residues/ wastes
• biorefinery
• value-added products

ACKNOWLEDGMENTS

The authors would like to thank the U.S. Department of Agriculture ARS for funding support for biofuel residues research in the College of Tropical Agriculture and Human Resources (CTAHR), University of Hawai’i at Mānoa. They would also like to thank the anonymous reviewers and Dr. Makkar Harinder of FAO for their valuable inputs.

Notes

^aModified from Wilkie et al. (2000).

^bModified from de Menezes (1989).

^cModified from Harada et al. (1996).