Rok and Diageo's 'distillery of the future'

12 January, 2009

A new whisky distillery with environmental credentials. By Simon Ellery

ProjectRoseisle whisky distillery
Contract value £40 million
ClientDiageo
Lead consultantFaber Maunsell
Main contractorRok on £11.5 million contract
Biomass and water treatment subcontractorDalkia and sister company Veolia
Coppersmiths Abercrombie

Drinks giant Diageo has combined traditional trades and incorporated cutting edge green technology to construct what it claims is the ‘distillery of the future’.

Using traditional copper craftsmanship to build fourteen copper stills with biomass technologies in a new way, the firm is poised to unveil Scotland’s first new whisky distillery for three decades.

Diageo, which is investing £40 million in the project, says the new distillery will be up and running early this year 2009. That is just 15 months after starting work on site.

Main contractor Rok came on site toward the end of 2007 with a brief to build the Roseisle distillery in Elgin, Morayshire, which is North-east of Inverness. Rok coordinated the whole construction package, including the main building, the distillery as well as the biomass, water treatment and reclamation plants.

In a break from building tradition, it was engineers Faber Maunsell and not the architects, who were the lead consultants. This came about because the project was driven by the distilling process and engineering, says project director Richard Mann.

He says: “The challenge for Rok was coordinating the work of all the specialists to build a large bespoke brewery in such a short timescale. They were taking on a project that relied on specialist skills that had not been used for decades – it was extremely challenging for them. Everybody enjoyed working on the project.”

The challenges were overcome through the use of a management contractor and early contractor involvement along with early procurement of key packages of work – that being the steelwork and ground improvement works. He says civil and process work operations overlapped where possible.

A Rok spokesman adds: “Diageo is fitting out the distillery using its own specialist contractors and we are making sure the construction programme fits in with its requirements.”

The distillery’s layout was designed to enable easy maintenance of the stills while the overall building had to blend in with the environment.

Nathaniel Buckingham, Faber Maunsell project manager, says: “Being an industrial process, the challenge was to design a building which reflects the distillery process function while attempting to break down the mass, scale and visual impact of the development to respond to its setting.”

He says the building is a steel frame, clad structure with a concrete foundation on vibrostone columns – a process where soil and stone is vibrated into the ground and steadily compacted to create strong load-bearing columns.

With 27 malt distilleries across Scotland, Diageo’s latest employed traditional coppersmith skills that it claims has a big impact on the spirit produced.

Skilled coppersmiths at Diageo’s Abercrombie workshop built the stills – which weigh 5-6 tonnes each and are 4 metres in diameter and 8 metres high. They were shipped 274 kilometres from the small town of Alloa, near Stirling, by lorry. Crafting copper – which is a highly malleable material - is an art and the 14 stills took four months. The most time-consuming part is sculpting the “shoulders” which must be hammered into shape by hand.

“Traditional coppersmith skills have a huge influence on the spirit which is produced,” says Brian Higgs, Diageo’s malt distilling director. They were transported in sections and assembled on site and a team of coppersmiths travelled to ensure the stills were safely installed.

Throughout the project engineers and the contractors faced a tight schedule. The design process started in March 2007 and planning and building warrants were obtained over the summer. Work started in October 2007 and the finishing touches are coming to an end.

With such a short timescale, steel was chosen for the main building’s frame to speed up the erection time. By June the 3,000 cubic metre structural frame of the building was complete. The steel frame structure, which is comprised of two independent sections to allow structural thermal movement, is over 100 metres long and weighs around 800 tonnes.

Another challenge facing engineers was using structural steel to support a variety of equipment used in the distilling process. This includes two large circular, flat-bottomed vessels for mixing the raw ingredients called mash tuns, large fermenting tanks as well as the fourteen stills.

Rok’s spokesman says: “A major element of the job has been the lifting in and installing of huge storage tanks and stills and their associated equipment. The stills are so big that it has been necessary to get them installed during the construction stage as it would not be possible to get them in afterwards.”

The three key processes involved in whisky distilling are mashing, fermenting and distilling. Barley is malted which involves kiln drying with peat traditionally used as a fuel. The malt is mixed with hot water into the mash tun. Mashing releases starch which then breaks down into sugar and when yeast is added turns to a liquid that has the same alcoholic strength as weak beer. A large volume of this “wash” is boiled and the steam is condensed to leave a small volume of spirit.

That is then distilled again to give it strength and flavour. The spirit is then left in oak casks for at least three years to qualify as whisky although many distilleries leave it for up to 20 years further to improve.

In an eco-friendly move, waste from the distilling process – in the form of malted ground barley grains – powers a biomass boiler. Added to this, a water treatment system reduces water consumption by half, saving around 300,000 cubic metres each year.

Heating costs will also be cut through the sighting of the distillery next to the maltings plant so that waste heat from the distilling process is recycled back into the plant.

Diageo called in Faber Maunsell in 2006 for advice on the biomass process. The firm had advised another rival distiller years ago but this was the first time the technology was going to be commissioned and built.

The project has been entered for a BREEAM “excellent” ward and the combination of green innovation and traditional craftsmanship will help produce a relatively environmentally friendly whisky around 2012.