In 2021, the UK food and beverage processing industry experienced a significant shortfall in the availability of carbon dioxide. A sharp increase in the rise in wholesale gas prices affected production capability, meaning this essential gas, which is used the drinks industry for soft drinks and some beers, and in packaging to extend the shelf life of fresh food products was in high demand.

At this time, the British Compressed Air Society (BCAS) urged food produces to consider the benefits of on-site nitrogen generation, to help mitigate the risk of CO2 gas shortages in the future.

Why nitrogen?

As an inert gas, nitrogen can be used in place of carbon dioxide in smaller breweries, to remove oxygen when purging tanks, thus preventing oxidation and contamination.  It can also be used for clean in place (CIP) pipework and vessel purging, for assisted filling to increase process speed and during bottling to help extend shelf life.  

Elsewhere in the food processing industry, modified atmosphere packaging is used to replace oxygen with nitrogen, significantly slowing down the process of decay by inhibiting oxidation and the growth of microbes.

Unlike carbon dioxide, nitrogen can be produced cost-effectively as a by-product of the air compression process, which can reduce the cost of bought-in gas, in cylinders or in bulk, by as much as 90 per cent.  

By reducing the amount of gas that needs to be bought in, minimising waste and eliminating the need for storage, on-site nitrogen generation can also reduce supply costs. A company that currently uses liquid nitrogen can expect an on-site system to pay for itself completely in less than two years, whereas one that buys in gas cylinders could have a payback period of as little as one year.

Compatible with standard industrial compressor systems, many manufacturers now offer nitrogen generators, in which pre-treated air is filtered, and the oxygen and water is removed. This leaves high-quality nitrogen, which can be captured at source, and reused for other processes.

Matching production to demand

With only minimal investment in an on-site nitrogen generator, this process enables companies to match their production to help meet gas demand, providing greater control over the volume of gas required.

With some customers of BCAS members quoting pay-back periods of as little as one year when replacing bough-in cylinders with an on-site nitrogen generator, it is certainly worth speaking to your supplier to discover whether nitrogen gas could offer an alternative to an existing CO2 supply.  

Not only could this help improve on-site productivity and ease the logistics of gas storage, but with forecasters predicting that energy prices will continue to rise, it could help to mitigate against future supply-chain issues too.

Food producers keen to learn more about on-site nitrogen generation can download a factsheet from the BCAS website or contact their BCAS supplier for further information.

Vanda Jones is executive director, British Compressed Air Society (BCAS) 

www.bcas.org.uk

Tel: 020 7935 2464