Whisky distillery set to convert by-products to biobutanol

A Scottish whisky distillery is to become the first in the world to have its by-products converted into advanced biofuel capable of powering vehicles fuelled by petrol or diesel.

Tullibardine, an independent malt whisky producer in Blackford, Perthshire, has signed a memorandum of understanding with Celtic Renewables, an Edinburgh-based company that has developed the technology to produce biobutanol from the by-products of whisky production.

Tullibardine has the capacity to provide 6,500 tonnes of draff, which are kernels of barley soaked in water to facilitate the fermentation process, and two million litres of pot ale, a yeasty liquid that is heated during distillation.

At a cost of £250,000, these by-products are currently spread on agricultural fields, turned into animal feed or discharged 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.

Celtic Renewables, a spin-out company from the Biofuel Research Centre (BfRC) at Edinburgh Napier University, aims to build a processing plant in Scotland that will help grow an industry projected to be worth £60m a year.

The pilot demonstration project, said to be a first for Scotland, is being funded with the help of a £155,000 grant from Zero Waste Scotland.

Iain Gulland, director of Zero Waste Scotland, said: ‘To become a zero-waste society we need to find new, innovative ways of turning wastes and by-products into high-quality products.

‘As well as having clear environmental benefits, this project has the potential to lead the way in realising cost savings across Scotland’s whisky industry, unlocking hidden value and helping to boost the economy.’

While the original proof-of-concept research, conducted at Edinburgh Napier, was at a 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.

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.