This paper discusses the state of current bioenergy platforms, the impact of the new biology of genomics on biomass conversion, and the biorefinery of the future. A biorefinery is herein defined as a facility that integrates biomass conversion processes and equipment to produce fuels, power, and chemicals from biomass. The biorefinery concept is analogous to today’s petroleum refineries, which produce multiple fuels and products from petroleum.
In order to discuss what the future may hold when it comes to the bioeconomy, it is important to examine where we are today with respect to the current bioenergy platforms. Both dry and wet mill ethanol production from corn starch (U.S.) and ethanol production from sugarcane (Brazil) are regarded as essentially mature technologies for producing bio-ethanol. Currently, dry-grind ethanol plants produce the majority of fuel ethanol (ca. 60%) in the U.S. Given concerns regarding net energy balance and the food versus fuel debate, ethanol production from corn is expected to level off (von Braun, 2007). However, some incremental increases in energy efficiency of these processes can be expected as coproduct utilization (e.g. distiller’s grains and bagasse) is incorporated into next generation plants. Currently, distiller’s grains from corn ethanol production are used as animal feed, while most of the bagasse from sugar cane production is burned for power generation.
More than eight million metric tonnes of distillers grains (DDGS) are expected to be produced in the U.S. by the end of this year. Some experts are predicting that DDGS production in the U.S. will reach up to 15 million metric tonnes in a few years (University of Minnesota, 2008; Archibeque, Freetly, and Ferrell, 2008). In addition to starch, distiller’s grain contains fiber, which is composed of cellulose, xylan and arabinan. If these coproducts were further hydrolyzed and converted into liquid fuels or other bioproducts, the efficiency and profitability of these plants would be expected to improve even further. In order to accomplish this, technologies have to be developed for de-construction and enzyme treatment of the fiber component present in DDGS. Members of The Midwest Consortium for Biobased Products recently completed a comprehensive study on the utilization of DDGS that will be published in a special edition of Bioresource Technology. As part of this study, the fermentation of DDGS hydrolysates to biobutanol by the solvent-producing clostridia was examined (Ezeji and Blaschek, 2008).
http://ageconsearch.umn.edu/bitstream/48717/2/What Are the Possibilities for the New Bioeconomy .pdf