How to produce your own nitrogen for beer brewing

Breweries use nitrogen gas for a wide range of tasks, from nitrogenation to packaging and transportation to homogenising. Many brewers are also turning to nitrogen as an alternative to CO₂. The question is, have you ever wondered how to produce nitrogen on-site?

With the CO₂ shortage driving prices up and brewers looking for viable alternatives, generating your own nitrogen is a game changer.

In this article, we explain how to produce nitrogen for your brewery without the need to hire regular refill bottles. We cover the benefits of nitrogen generation, focusing specifically on breweries in New Zealand.

Uses of nitrogen in breweries

Whether you run a large-scale brewery or a smaller craft brewery, nitrogen is a key resource in the beer brewing process. Common applications include the following:

Nitrogenation
Packaging
Transportation
Purging equipment
Tank blanketing
Forced carbonation
Maintaining pressure in dispensing systems
Homogenising
Inerting to protect sensitive ingredients
An alternative to CO₂ gas.

Whether you use nitrogen for some or all of these tasks, producing your own nitrogen will help to reduce delays and operational costs. We explain more about the benefits below.

How to produce nitrogen on-site

An on-site nitrogen generator allows you to produce your own nitrogen in your brewery, drawing it from the atmosphere. This way, you won’t need to hire nitrogen from a supplier every time you run out.

What is a nitrogen generator?

An on-site nitrogen generator produces high-quality nitrogen on demand. They work by separating nitrogen from other molecules to be used in its purest form. As nitrogen is the most abundant gas in the atmosphere, it is a more reliable gas supply than other alternatives, including carbon dioxide.

Nitrogen generators are efficient, cost-effective, and environmentally friendly, providing a reliable source of gas without the need for frequent deliveries.

Types of nitrogen generators

There are two main types of nitrogen generators – membrane nitrogen generators and pressure swing adsorption nitrogen generators.

Membrane nitrogen generators

In a membrane nitrogen generator, semipermeable membranes separate compressed air into its component gases. At one end, the compressed air is forced through the fibres in the membrane. Oxygen, water vapour, and trace gases can easily pass through but nitrogen is contained within the membrane where it flows through the outlet port and is ready for use.

Membrane nitrogen generators are best suited to applications where the required flow of nitrogen is relatively low and purity levels do not need to exceed 99%. They also cost less upfront than Pressure Swing Adsorption (PSA).

Pressure Swing Adsorption nitrogen generators

In a Pressure Swing Adsorption Generator (PSA), there are two separate pressure vessels – tower A and tower B. Each tower is filled with carbon molecular sieves that switch between a separation process and a regeneration process.

At the beginning of the separation phase, clean, dry compressed air enters tower A. Next, oxygen molecules pass through the tower A sieve while nitrogen molecules bypass it. Some of this nitrogen flows into tower B, triggering the regeneration phase and the rest is ready for use.

The opposite flow of nitrogen in tower B pushes oxygen from a previous separation phase out of the sieves. When the oxygen has been removed, a new cycle of compressed air is introduced for separation. The cycle then repeats, alternating between each tower.

The initial investment cost for PSA generators is higher than membrane generators but the higher flow and higher purity levels are often worthwhile. For breweries, investing in a PSA generator ensures sufficient air purity levels, helping to ensure your beer is safe and consistent every time.

Benefits of on-site nitrogen generation

On-site nitrogen generation system

Being one of the most abundant gases in the atmosphere, nitrogen is a cost-effective alternative to carbon dioxide. Following the recent closure of Marsden Point Oil Refinery, many brewers have struggled to source the CO₂ they need, with prices tripling in the last 6 months of 2022.

To ease the pressure on your brewery, nitrogen generation allows you to operate uninterrupted. It’s also much more cost-effective as you can run the generator as required, not relying on expensive hireage.

No third parties

On-site nitrogen generators eliminate the need for a third-party supplier. You can produce the gas you need directly on the premises, ensuring a consistent, reliable source of nitrogen. This protects your brewery during industry-wide shortages, price spikes, and delivery disruptions.

Unlimited supply

Nitrogen is not affected by shortages or supply chain disruptions because it makes up approximately 78.08% of the Earth’s atmosphere. In comparison, carbon dioxide accounts for less than 0.04%. An on-site generator also allows you to produce nitrogen on demand, even while others in the industry are worried about limited supply.

Lower costs

With lower production costs, reduced waste, fewer delivery costs, and more control over your gas supply, an on-site nitrogen generator can dramatically improve your bottom line. With production on your premises, it’s also easier to track your expenses and make adjustments as necessary.

Reduce your carbon footprint

While carbon dioxide is a greenhouse gas produced from burning fossil fuels, nitrogen is a more sustainable gas for beer brewing. By producing nitrogen on-site, you can reduce your carbon footprint with lower energy consumption and less waste.

Less waste

An on-site generator can produce the exact amount of nitrogen that is required, unlike cylinders or tanks. The generator can be easily adjusted to match your current demand, optimising the amount of nitrogen produced at any given time. This reduces waste, lowers costs, and improves overall efficiency.

Nitrobrew

Nitrobrew nitrogen generator for craft breweries

At Industrial Air Systems, we’ve launched our Nitrobrew nitrogen generator system specifically designed for breweries. Complete with everything you need in one compact, skid-mount system, the Nitrobrew makes it easy.

Features of the Nitrobrew system include: