On-site nitrogen generation boosts productivity at Irish brewery

Northern Ireland-based Whitewater Brewery is a thriving craft beer operation that was established in 1996 on a fifth-generation family farm in Castlewellan, County Down, and produces a wide range of award-winning standard and bespoke cask real ales, keg beers, stout, and lagers. By combining traditional production methods with advanced technology, the company has seen expansion from an initial 800-litre brew size to the handcrafting of 6,500-litre brews and the bottling of 10 different beers on-site.

This substantial increase in productivity from its processes was aided initially by the brewery’s energy-efficient Atlas Copco compressed air system and now, even more so, by its recent addition of an on-site nitrogen generation system. This ensures continuity of supply and achieves significant operational cost savings compared to using bought-in nitrogen or carbon dioxide (CO₂).

Like similar operations within the brewing industry, Whitewater Brewery has seen a growing reliance on nitrogen gas for several stages and process applications throughout the beer-making process. Typically, these range from flushing pipework and tanks to eliminate unwanted CO₂ and oxygen, and purging residual wort or mash from completed batch vessels to prevent the risk of contamination spoiling the next brew batch. Pressurised nitrogen gas can serve as the ideal medium to aid the flow of beer from one tank chamber to another and to facilitate pressurised keg filling, as well as all other filling, bottling and canning operations.

Cost-efficient solution
As Bernard Sloan, the founder and managing director of Whitewater Brewery, has discovered, on-site nitrogen generation offers a more sustainable and cost-efficient solution than reliance on nitrogen or carbon dioxide gas delivered in cylinders or as bulk liquid supply, which all require transport, handling, and dependence upon supplier delivery schedules.

The brewery now operates with an Atlas Copco GA 7 VSD+ FF rotary screw compressor to supply 10-bar clean, dry air, and an NGP15+ nitrogen generator (this incorporates the latest pressure swing adsorption — PSA technology) to provide an independent, reliable, and flexible supply of premium grade nitrogen at the 99.5% purity level required.

A specific benefit derived from the on-site generation facility is its contribution to nitrogenated beer production, such as Irish stout, which contains more dissolved nitrogen gas and less CO₂ than traditional beer, giving it a thicker and longer-lasting foam; the new nitrogen generation system has also reduced the brewery’s reliance on CO₂ within its processes — and the associated costs.

Mr Sloan added: “We were using a tonne of CO₂ every week from delivered bulk supply, which was costing more than £1,000 for each delivery during supply shortages. The on-site nitrogen has replaced many of the CO₂ duties throughout our production and, as a result, we have been able to limit the supply programme to just one delivery every five weeks. This is saving us around £35,000 per year on CO₂ costs — and reducing our carbon emissions.”