A researcher at Queen’s University Belfast has developed a low cost technique to convert left over barley from alcohol breweries into carbon, which could be used as a renewable fuel for homes in winter, charcoal for summer barbecues or water filters in developing countries.
Breweries in the EU throw out around 3.4 million tons of unspent grain every year, weighing the equivalent of 500,000 elephants, according to Queen’s University Belfast.
One of its researchers, Dr Ahmed Osman from the School of Chemistry and Chemical Engineering, has now come up with a process that converts just 1kg of the grain into enough activated carbon to spread across 100 football pitches.
“There are only a few steps in our low cost and novel approach – drying the grain out and a two-stage chemical and heat treatment using phosphoric acid and then a potassium hydroxide wash, both of which are very low cost chemical solutions,” explained Osman.
“This then leaves us with activated carbon and carbon nanotubes – high value materials which are very much in demand.”
According to Osman, liquid forms of carbon are normally shipped to the UK from the Middle East, and solid biocarbon in the form of wood pellets is shipped from the US and elsewhere. The new techniques makes it possible to use more locally produced resources, which reduces emissions linked with the agriculture sector.
“Across the globe there is a real demand for carbon as it is used to create fuel for households, parts for water filters and charcoal for barbecues,” Osman said.
“If we are able to take something that would otherwise be a waste and turn it into a useful biofuel, it can only be a good thing for our planet. It could really help to solve global waste and energy problems.”
Osman calls the conversion of barley waste into carbon “a prime example of the circular economy”.
Image credit: Sam Howzit via Flickr