Ethanol production has been blasted by everyone from academia to the UN for its undesirable effect of raising food crop prices. However, while researchers try to develop new production methods that don't use sugar crops; the current infrastructure chugs along producing more and more corn based ethanol daily. Barring a dramatic change of course, it seems unlikely that the growth of corn ethanol will stop in the short term.
Thus, while it may not be the best solution, technology such as a new fungal improvement to processing developed by Iowa State still do some good. The new research was also assisted by researchers at the University of Hawai'i. It involves growing fungi in leftovers of ethanol production. The process saves energy, helps recycle more water, and produces higher quality livestock feed, which is a byproduct of the processing.
Hans van Leeuwen, an Iowa State professor of civil, construction and environmental engineering and the leader of the research project states, "The process could change ethanol production in dry-grind plants so much that energy costs can be reduced by as much as one-third."
The rest of the Leeuwen's team is comprised of Anthony L. Pometto III, a professor of food science and human nutrition; Mary Rasmussen, a graduate student in environmental engineering and bio-renewable resources and technology; and Samir Khanal, a former Iowa State research assistant professor who currently is an assistant professor of molecular biosciences and bioengineering at the University of Hawaii at Manoa. The team won the 2008 Grand Prize for University Research from the American Academy of Environmental Engineers for the research.
The prize was awarded based on merit of research in environmental fields. The AAEE describes the selection process thusly: "Those chosen for prizes by an independent panel of distinguished experts address the broad range of modern challenges inherent in providing life-nurturing services for humans and protection of the environment. ... Their innovations and performance illustrate the essential role of environmental engineers in providing a healthy planet."
The Iowa research seeks to fine tune dry-grind ethanol production. In this type of production, raw corn is ground and then water and enzymes are added. The enzymes act to break down the corn's starch, into sugars, which are processed by added yeast. The yeast produces the end product -- ethanol -- through fermentation. Distillation follows to harvest the ethanol.
For every gallon of fuel recovered, there are approximately six gallons of waste known as stillage. The brothy waste is rich in organic solids and other organic compounds. These compounds are harvested by centrifugation and dried; yielding livestock feed known as distillers dried grains.
The leftover stillage contains some smaller solids. This type of stillage is known as thin stillage. Typically only a small percentage of this stillage, which contains valuable water and enzymes, can be reused in the production process. The rest is evaporated and the leftovers are mixed with distillers dried grains to form distillers dried grains with solubles. The downside is that water and expensive enzymes are lost in the process.
The researchers mixed in a special fungus, Rhizopus microsporus, into the thin stillage. The fungus thrived off the organic material and was found to remove 80 percent of the organic material from the water, allowing much more of the thin stillage (and thus the water and enzymes) to be recycled.
The leftover fungus hold superior nutrition value and can be harvested for livestock feed. It’s loaded with protein, amino acids, and other nutrients. It can be sold as a supplement individually or sold blended with distillers dried grains for a higher rate. Such feed is suitable for animals like hogs and chickens, which typical distillers dried grains are not as good for.
With the current infrastructure Leeuwen states that the elimination of evaporation of thin stillage would result in a cost savings of $800M yearly. Furthermore, the process would save $60M per year in enzymes and would reduce the industry's water load by 10B gallons per year. And there would be more profit, with the nutrient rich fungi feed bringing in almost $400M more yearly. The overall energy balance of production (and thus efficiency) would also be improved by lowering the inputs needed.
You don't find many investments like this -- the process could be implemented for only $11M in a plant that produces 100M gallons yearly, and it would pay for itself within six months.
The project is funded by grants of $78,806 from the Grow Iowa Values Fund, a state economic development program, and $80,000 from the U.S. Department of Agriculture through the Iowa Biotechnology Byproducts Consortium.
The researchers have filed for a patent on the new method and are currently looking for investors to help bring it to market. The bottom line Professor Pometto says is getting the technology out there as fast as possible and improving the struggling industry. He states, "We will be saving ethanol producers money and energy. That's the bottom line."