Scientists from Cornell have analyzed microbes in brewery waste, looking for ways to turn the beer by product into biofuel. Over the course of a year Largus T. Angenent and Jeffery J. Werner took samples from Anheuser-Busch InBev plants around the country in order to study the bacterial communities that exist within the bioreactors. They also collaborated with scientists at the University of Colorado in Boulder, and Washington University in St. Louis.
Using advanced software, the scientists analyzed over 400,000 gene sequences in bacteria taken from the sludge found in the nine different bioreactors. What they found was a dynamic system comprised of thousands of species of bacteria, 145 of which where unique to the specific nine different facilities. Knowing more about these biological systems may allow scientists to change the waste properties into something more beneficial.
The bioreactors the sludge was pulled from are million-gallon tanks, and when the microbes in the sludge interact, they can produce methane gas. In fact, Anheuser-Busch gets 20% of its heat energy from the methane produced in the tanks, an act that saves the company millions in utility costs each year.
In ongoing research, said the university, the Cornell engineers are looking to prevent methane production by the microbes, and instead, to shape the bacterial communities to produce carboxylates, which are a precursor to the alkanes found in fuels. The team doing the work has published its findings in the February journal of the Proceedings of the National Academy of Sciences under the abstract “Bacterial community structures are unique and resilient in full-scale biological systems.”