Scots Take Apt Approach to Biofuel

Aug. 19, 2010
Scottish process uses the two main waste products of whisky production.

The waste products of one of the world's oldest processes — whisky distillation — are poised to become feedstocks for biofuel thanks to work by engineers and scientists at Edinburgh Napier University in Scotland.

The University has just filed a patent for the new biofuel which has been in development over the last two years at its Biofuel Research Centre (BfRC). The BfRC itself was launched in December 2007 under the directorship of Professor Martin Tangney, an expert in the biological production of biobutanol.

A U.K. government research grant of £500,000 ($780,000), plus another £260,000 ($405,000) from the Proof of Concept program of Scottish Enterprise (Scotland's national economic development agency) have driven the development of the new fuel, which the BfRC says can be used in ordinary cars without any special adaptations.

The Edinburgh Napier team focused on the £4 billion ($6.2 billion) whisky industry as a ripe resource for developing biobutanol. As part of its research, the center was provided with samples of whisky distilling waste products from Diageo's Glenkinchie Distillery in the Scottish borders — home of The Edinburgh Malt brand.

The new process uses the two main waste products of the whisky production process: pot ale and draff.

Pot ale is what's left after the alcohol has been vaporized in the pot still and allowed to pass over the neck of the still into either a condenser or a worm — this being a large copper coil immersed in cold running water where the vapor is condensed into a liquid.

Draff is what's left after the malting process. After germination, the barley (so-called green malt)used in the distillation process goes into a kiln for drying. This halts the germination process and the dried malt is then ground into a coarse flour or grist, which is mixed with water in the mash tun (an insulated vessel). A three-stage water addition process drives the mashing process, which leaves behind a sugary liquid known as wort and the spent grains known as draff. In the past, draff has then been used in cattle feed.

With 1,600 million liters of pot ale and 187,000 metric tons of draff produced by the malt whisky industry annually, the BfRC believes that there's real potential for biofuel to be available at local filling stations alongside traditional fuels. The product can also be used to make other green renewable biochemicals, such as acetone.

The University now plans to create a spin-off company to take the new fuel to market and leverage the commercial opportunity, in the bid to make it available at gas pumps.

"The EU [European Union] has declared that biofuels should account for 10% of total fuel sales by 2020. We're committed to finding new, innovative renewable energy sources," said Tangney. "While some energy companies are growing crops specifically to generate biofuel, we are investigating excess materials such as whisky byproducts to develop them. This is a more environmentally sustainable option and potentially offers new revenue on the back of one Scotland's biggest industries. We've worked with some of the country's leading whisky producers to develop the process," he added.

Lena Wilson, chief executive of Scottish Enterprise also welcomed the breakthrough: "This pioneering research is testament to Scotland's world-class science base and demonstrates how Scottish Enterprise helps to transform cutting-edge knowledge into successful new high-growth sustainable businesses for Scotland. The Scottish Enterprise Proof of Concept Program is successful precisely because of its high caliber projects. By proactively taking innovative ideas from the laboratory to the global market place, Scotland can continue to

Politicians have also been quick to praise the work. Jim Mather, Scottish Minister for Enterprise, Energy and Tourism, said: "This is an innovative development, and I am delighted to see Edinburgh Napier University once again display its expertise in this field by bringing this biofuel to market. In these challenging economic times we need to play to our strengths and take advantage of the low carbon opportunities of the future. It's exactly this type of innovation that will help sustain economic recovery and deliver future sustainable economic growth."

Although details of the technology involved with the new process are being kept under wraps at the moment, the BfRC says that its inspiration came from a 100-year old process created by Chaim Weizmann, who studied butanol fermentation initially as part of a program to produce rubber synthetically. The process was then used in explosives manufacturing and helped the allies to win both World War I and World War II.

Seán Ottewell is Chemical Processing's Editor at Large. You can e-mail him at [email protected].