A startup company in Scotland is working to capitalize on the tons of waste produced by one of the country’s most valued industries and turn the dregs of whisky-making into fuel. Celtic Renewables, formed in 2011, has refined its process based on a century-old fermentation technique and is now taking the next step toward a commercial plant, according to an article in Chemical & Engineering News (C&EN).

Ann M. Thayer, a senior correspondent with C&EN, points out that making whisky requires three ingredients: water, yeast and a grain, primarily barley. But only 10% of the output is whisky, and the rest is waste. Each year, the industry produces 500,000 metric tons of residual solids called draff and 1.6 billion liters of a yeasty liquid known as pot ale. These by-products are usually spread on agricultural lands, turned into low-grade animal feed or discharged into the sea.

Rather than inefficiently re-using these materials or letting them go to waste, Celtic Renewables has taken an old industrial process developed to turn molasses and other sugars into chemicals and fine-tuned it to convert draff and pot ale into acetone, 1-butanol and ethanol. The latter two can be used as fuel. The company is scaling up its process with the help of the U.K. Dept. of Energy & Climate Change, private funds and Bio Base Europe. If all goes well, a commercial facility could be next.

Source: American Chemical Society