Doug Ross (MD - Tullibardine), Dr Doug Ward CBE, Prof Martin Tangney, Iain Gulland (Director of Zero Waste Scotland) and Mark Simmers at the Tullibardine Distillery

One for the road � making fuel from whisky waste

A Scottish whisky maker is to become the world’s first distillery to supply ingredients to make biofuel for vehicles from its waste products.

Independent whisky maker Tullibardine has linked up with Edinburgh Napier University to produce biobutanol, an advanced biofuel capable of powering vehicles fuelled by petrol or being incorporated into biodiesel.

Now a spin-out company from the university, Celtic Renewables, is looking at two sites to build a processing plant in central Scotland. The move could eventually see Scotland's 100-plus distilleries feed a new £60m industry.

At present some 97 per cent of Tullibardine’s whisky by-products are disposed of after production. They include draff – the sugar rich kernels of barley which are soaked in water to facilitate the fermentation process – and pot ale, the yeasty liquid that is heated during distillation.

Previously the distillery – 30 miles north-west of Edinburgh – has spent £250,000 a year to dispose of the draff and pot ale, spreading them on fields, making them into animal feed or safely discharging them into the sea under licence.

The distillery is currently supplying raw materials to help refine the conversion process at the Centre for Process Innovation (CPI) at Redcar, in Teesside. Tullibardine alone has the capacity to provide 6,500 tonnes of draff and two million litres of pot ale. Distilleries across Scotland currently produce around 600,000 tonnes of draff and two billion litres of pot ale.

The project hopes to identify the site of its new processing plant by the middle of next year with a capacity to take by-products from the many malt whisky distilleries across the highlands and islands of Scotland and a handful of large grain distilleries largely in the nation's central belt.

While the original “proof-of-concept” research, conducted at Edinburgh Napier, was at a small lab-scale of three litres of pot ale, this industrial scale second phase testing at the CPI will systematically scale up to 10,000 litres.

A bacterial fermentation process known as Acetone-butanol-ethanol (ABE) produces acetone, n-Butanol and ethanol from starch. Biobutanol gives 30 per cent more output power than ethanol.

Unlike ethanol, the nature of the innovative biofuel means that ordinary cars could use the more powerful fuel instead of traditional petrol.

Biobutanol can be used as a direct replacement for petrol, or as a blend, without the need for engine modification and it may also be blended with diesel and biodiesel. The product can also be used to make other green renewable bio-chemicals, such as acetone.

Professor Martin Tangney, director at the university's Biofuel Research Centre and also the Celtic Renewables’s founder and chief scientific officer, has helped develop the process. He said: “Our partnership with Tullibardine is an important step in the development of a business which combines two iconic Scottish industries – whisky and renewables. This project demonstrates that innovative use of existing technologies can use resources on our doorstep to benefit both the environment and the economy.”

The project has the support of ministers who believe it can contribute to the Scottish government’s target of reducing carbon emissions by 42 per cent by 2020 as well as contributing to the EU mandated biofuel target of 10 per cent by 2020.

Douglas Ross, the managing director of Tullibardine, said: “We are delighted to be partnering Celtic Renewables in this innovative venture, the obvious benefits of which are environmental. It takes a cost to us and turns it into something that has social as well as commercial value.”

Mark Simmers, chief executive of Celtic Renewables, said: “By piloting the fermentation at commercial scale we will demonstrate the viability of the process as a new and important industry of potential scale for Scotland.

Because distilleries currently produce around three times more pot ale than draff, the company is also considering other sustainable sources of sugar-rich raw materials, such as the by-products from breweries or paper waste, to help it convert the excess into biofuel.

“If we were to use all the by-products from Scottish distilleries, it would still leave us with almost 1.5 billion litres of pot ale. We could make at least the same volume of fuels again by using alternative waste or residue material such as paper and brewery waste.” 

The Biofuel Research Centre was established by Prof Tangney at Edinburgh Napier University in 2007 and was the first such centre of its kind, set up for the purpose of developing sustainable biofuels.

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