Thanks to Columbia researchers, peanut shell-powered cars may be on the horizon.
According to a new study, peanut shells and other materials, such as tree bark and grass, can be turned from biomass—a renewable energy derived from a recently living source—into fuel.
And the results are more than just peanuts: the findings show that biomass can be converted into liquid fuels while simultaneously recycling carbon dioxide and saving water.
The new process, researchers say, improves on the biomass “gasification” process—the conversion of biomass into fuel—by utilizing carbon dioxide in a new way.
Led by assistant professor of Earth and Environmental Engineering Marco Castaldi and post-doctoral researcher Heidi Butterman, this work provides a beneficial outlet for carbon dioxide during the production of fuel.
Gasification techniques have been used in the past, but scientists typically encountered problems with high water and energy consumption. This new process ameliorates both issues.
To Castaldi, the results initially seemed too good to be true. “For about the first six months [of this research] I thought something was wrong with the calculations,” he said. Castaldi was excited about the twofold benefit of using carbon dioxide, which both increased overall efficiency and reduced the amount of water used in the process.
While a typical gasification process uses only steam to convert biomass into syngas, synthetic gas containing a mixture carbon monoxide and hydrogen, Castaldi’s new method replaces 30 percent of the water with carbon dioxide. Researchers believe that these findings carry exciting potential and hope the process will be able to improve the overall efficiency of fuel production when used on a large scale. Syngas can be converted into a variety of different chemicals and fuels, including diesel products.
Though this technique has yet to be put into widespread use, it is now being tested on a larger scale by the University and a private company, whose name Castaldi declined to disclose. Castaldi hopes that in the future, carbon dioxide will be sequestered from industrial plants and used in this gasification process.
Currently, Castaldi and his research team are working on perfecting the process. They are experimenting with a wide range of biomasses from “poplar trees to beach grass to peanut shells,” he said.
Castaldi and his fellow researchers are also exploring the possibility of using municipal solid waste, which is essentially just trash, instead of biomass. “When I did this [gasification] for biomass I started wondering if I could use it on waste,” he said. This potentially could enhance the “greenness” of this process even further.
Though this research began just a few years ago, it is already creating possibilities for putting carbon dioxide to better use in the future. With some tweaking of the process and an appropriation of funding, Castaldi hopes that this improved gasification technique will be able to play a major role in the search to find more sustainable energy sources.