Spent grains and other by-products from whisky production are being put to use in some unusual and innovative ways. They could even provide an eco-friendly solution to some of our planet’s biggest environmental challenges.
More than 90% of produce from whisky distilleries is not in fact whisky; leftovers such as pot ales and draff have been used in the past for the likes of fertilisation and feeding cattle. In recent years, these by-products have proven to be vitally important when used in the right way, providing sustainable solutions to help both our environment and the economy.
Whisky has been enjoyed as a drink for hundreds of years, it is also sometimes used in cooking and has been recognised for its medicinal benefits, sterilisation, for warming people internally and even as a fuel for starting fire.
Here are four remarkable ways which whisky by-products are being used (and if they end up producing more whisky to create by-products, we’re not complaining!)
Tackling Radioactivity with spent whisky grains
We are all well aware of the dangers associated with radioactivity. The 1986 mass accident in Chernobyl was devastating in terms of casualties, the socio-political fallout and the cost to our environment.
So far we haven’t developed an efficient method of eradicating radioactivity; it is controlled rather than eliminated. Chernobyl and other areas devastated by radiation have been ‘treated’ with multiple methods involving massive financial, human and scientific resources.
The rubble and debris at the Chernobyl site absorbed much of the radioactive waste. There was both natural debris but also around 5000 metric tons of material dropped from helicopters, such as bags of sand, lead and boric acid. Costly measures were put in place to prevent further contamination and to try and restore some of the environment affected (farm land, animals, water sources etc.).
Another issue surrounding the ‘clean up’ of radioactivity is where to dispose of and store the radioactive waste. Radioactivity when absorbed, generates extreme high temperatures; it needs to be cooled to avoid it melting down and resulting in a contaminating explosion. To tackle this, the site is flooded and chilled with cold water, but the question then is where to dispose of millions of gallons of polluted water. Ultimately the best solution is to develop an efficient means of eradicating the dangerous substance. When materials such as uranium have a half-life of roughly 4 billion years, it is not a feasible solution to wait it out. Recent developments at Scotland’s Environmental Research Institute have displayed positive signs that there may be a cost-efficient solution via the process of Biosorption; using biological materials such as spent whisky grain.
Biosorption is a process where alternative non-living biological materials, such as seaweed, coffee grounds and spent grain are being used to reduce and hopefully eliminate radioactive products. Artificial man-made materials can be used to absorb radioactive waste but it’s a costly solution that doesn’t completely ‘solve’ the issue; just contains it. Small extracts of silver and gold have already been removed from sewage via the process of biosorption.
Scientists are practising this new method at the Dounreay nuclear site, in an effort to tackle radioactive waste, disposed of near Thurso in Scotland, between 1959 and 1977.
Leader of the Dounreay Shaft and Silo project team, Mike Gearhart told the BBC: "We still have a number of issues to address but results to date have been very promising."
Scottish distilleries could find themselves with a new purpose if whisky by-products result in a sustainable solution in the neutralization of radioactive waste.
Eco-friendly fuel made with whisky by-products
If tackling radioactivity wasn’t already enough, whisky by-products are also being developed into a new biofuel, to power cars and planes. By modifying a traditional method of fermenting sugar, it is now possible to produce butanol from pot ale and draff. The biofuel could be available at petrol stations in the foreseeable future and is compatible with conventional cars; no engine adaptions required.
Together, Celtic Renewables and independent malt whisky producer, Tullibardine Distillery are conducting the process of specific bacteria feeding on whisky by-products to produce butanol - a sustainable replacement to fuel vehicles.
This development is looking promising with butanol proving to be an efficient alternative, giving out 30% more power output than biofuel, ethanol. With many biofuels posing a threat to forests and wildlife, there is another reason why environmentally-friendly butanol may quickly become a preferable eco-friendly fuel.
Managing director of Tullibardine, Douglass Ross said “It takes a cost to us and turns it into something that has social as well as commercial value”. With distilleries spending money on the disposal of by-products, it would benefit not only the environment but also the whisky producers.
Biomass and biogas made with grain from whisky distilleries
In recent years, whisky distilleries in Scotland have pioneered in whisky-powered bioenergy. By-products from the whisky making process, such as spent grains and pot ale and are being utilised to generate electricity to power homes and heat both whisky distilleries and the local community. The £50million Rothes project, between Helius Energy and Rothes Distillers (CoRD) uses by-products from distilleries such as Macallan distillery and Glenlivet distillery as well as well-known brands such as Chivas Regal and Famous Grouse.
Whisky making by-products, ‘spent wash’ and ‘draff’ are separated into solids or liquids (aqueos streams). The biomass (solids) is then used as a fuel, whereas the liquid produces biogas via the process of anaerobic digestion. Steam or electricity is then created from the biomass and biogas.
Glendullan’s £12million bio energy plant has seen the carbon footprint of the distillery reduce by around 2,000 tonnes of carbon dioxide a year. If renewable projects such as this continue to grow we can improve on the economy and most importantly, the environment.
Lord Dunlop, Scotland Officer Minister when touring a distillery in Speyside said “It’s good for the planet, good for the whisky industry and good for the Scottish economy.”
Purifying poisoned water with DRAM
The people of Bangladesh have a 1 in 5 chance of dying from chronic arsenic poisoning. This horrifying fact desperately needed to be addressed, when Dr. Leigh Cassidy developed DRAM (Device for the Remediation and Attenuation of Multiple pollutants), to clean pollutants from water.
By combining draff (a whisky by-product residue) and a secret ingredient called DRAM, Dr. Leigh Cassidy developed a filter system to successfully purify contaminated water sources in Bangladesh. Native materials such as coconut shells and rice husks are utilised in this process, making it a cheap, sustainable solution. No electricity is required to power the filter as it relies on gravity; the only maintenance required is for the filter to be changed every six months, which can then be used as biofuel.
Cassidy is now working with PurifAid to help villagers in Bangladesh; using Cassidy’s model to deliver purified safe water to surrounding villages. Remarkably around 95% of arsenic particles from water are removed by the DRAM, making water safe to drink for those in Bangladesh who have suffered the “largest daily mass poisoning in history”.
DRAM is also being used in the purification of contaminated soil and farm land and is now used in the UK to purify water at industrial facilities. With PurifAid hoping to expand this system globally, to countries like Vietnam, China and Africa the future is looking bright.