When making beer, the byproducts can be just as desirable as the nationally beloved amber liquid that leaves the tap.
Most breweries sport a long list of brewing waste, but on top of this list of cast off ingredients are the grains brewers use to flavor their fermentations. These leftover grains represent 85 percent of an average brewery’s waste. It can take as many as seven barrels of water to generate just one barrel of beer and all the wastewater can’t be put back into the local water supply without costly filtration. Also, to brew one keg of beer, breweries vent close to six kegs of carbon dioxide into the atmosphere.
Throughout the history of beer, brewers have tried to reuse the grains leftover from the brewing process for other purposes. For example, bakers have used the spent grains to make bread and energy bars. But in Gunbarrel, Colorado Avery Brewery Co. and scientists at the University of Colorado Boulder, are trying to do more with the byproducts from brewing—including creating soda ash and a material for a more efficient lithium-ion battery.
“Alcohol stays in beer—that’s what everybody likes about beer,” said Dan Driscoll, the Quality Assurance Manager at Avery Brewery. “[The] CO2 needs to go somewhere.”
And it would be better for everyone if breweries like Avery Brewery didn’t pipe their carbon dioxide into the atmosphere, because excessive amounts of carbon dioxide within the Earth’s atmosphere contribute to the planet’s increasing temperatures and changing climate.
Driscoll said Avery Brewery currently vents the carbon dioxide outside, but they want to change this procedure in the future. They want to collect the carbon dioxide produced while Avery’s beers and ales ferment and mix it with caustic soda. The result is the ever useful soda ash. Avery plans to send the soda ash out to O-I, a glass bottle producer in Windsor, Colorado. O-I will add it to the silica sand used to make Avery’s beer bottles. With the additional soda ash, the silica sand melts at a lower temperature, thereby reducing the amount of energy needed to form the beer bottles.
Avery Brewery is also connected to the invention of a new, and initially slimy, carbon source for an energy storage devise at the University of Colorado Boulder.
Scientists at the University of Colorado Boulder took advantage of Avery Brewery’s daily output of 35,000 gallons of wastewater and created a key component for a lithium-ion battery. To produce a rechargeable battery similar to the one in a cell phone, the team had to grow a piece of the technology.
The team added a sugar-loving fungus—Neurospora crassa—to the sample of carbon and sugar rich wastewater and watched it thrive.
“The wastewater is ideal for our fungus to flourish in, so we are happy to take it,” said, Tyler Huggins, the lead author on the project in an article with CU Boulder Today.
The fungus ate the nutrients in the water and grew until it was a lumpy fungus-filled slop. At this point the team drained the water from the mixture and cooked the fungus down—polarizing it—into its most carbon-rich form.
“Out pops this carbon, and that goes right into the battery, that will be one-half of your lithium-ion battery,” said Justin Whiteley, a researcher at the University of Colorado, to Fox 31.
Those little burnt crisps provide the carbon needed to create “one of the most efficient naturally-derived lithium-ion battery electrodes” that also cleans wastewater.
If breweries around the nation applied such a practice, it is possible they could dramatically reduce the amount of money they spend on reintroducing wastewater into the municipal system.
“They can’t just dump it into the sewer because it requires extra filtration,” said Huggins.