Nitrogen. A hot topic frequently discussed in the media over the past years. It led to slower driving in the Netherlands and has caused companies in Europe to be denied new permits. So why does 78% of the air we breathe consist of nitrogen?
What is nitrogen?
Nitrogen can have different meanings. The most correct meaning of nitrogen is the nitrogen atom, represented by the symbol N in the periodic table of elements. It can form various compounds, some of which are environmentally harmful, such as NOx and NH₃. Nitrogen naturally exists as N₂, and when we talk about nitrogen in this blog post, we refer to this form. Nitrogen (N₂) is a colorless, odorless and inert gas that makes up the majority of our atmosphere. In its pure gaseous form, it is non-reactive (inert) and does not play a direct role in the chemical processes of living organisms. However, nitrogen in other forms is essential for life, serving as a building block for proteins, DNA and other important biomolecules.
In addition to its biological functions, nitrogen has countless industrial applications. It is used to work safely in potentially hazardous environments and plays a key role in preventing chemical reactions, keeping food fresh, acting as a shielding gas during welding processes, preserving samples and even removing warts through nitrogen treatment!
Inerting: safety first
In industrial environments where fire hazards or unwanted chemical reactions can occur, it is crucial to displace oxygen from certain areas. This process, known as inerting, uses nitrogen to create a stable and safe environment. Nitrogen is commonly used in the (petro)chemical industry to inertize reactors, storage tanks and pipelines when working with hazardous substances. In the food industry, nitrogen (or CO2) helps keep packaged products fresh by replacing oxygen, thus preventing spoilage.
Flushing (inerting) with nitrogen
Nitrogen also plays an important role in handling certain liquids. It removes dissolved gases like oxygen and carbon dioxide, which is crucial in the production of high-quality chemicals, medicines and food products. By allowing nitrogen to flow through the liquid, unwanted gases are removed, enhancing the safety and quality of products. In the oil and gas industry, nitrogen is used to flush (degass) pipelines, storage tanks and ships during commissioning or decommissioning to safely remove hazardous or explosive gases and vapors.
How does nitrogen work with fire suppression?
A fire requires three elements to start and continue burning: fuel, oxygen and an ignition source, this is also known as the "fire triangle". Nitrogen is used to remove the oxygen component of this triangle and to lower high temperatures (cooldown process). By reducing the oxygen concentration in a space to below the level required for combustion (typically under 8%), the fire is extinguished. This makes nitrogen an effective fire suppressant, especially in enclosed or hard-to-reach areas.
The benefits of nitrogen
- Environmentally friendly: Nitrogen is a natural and non-toxic gas that is abundantly present in the atmosphere, making it an environmentally friendly choice.
- Minimal damage: Since nitrogen does not damage equipment or goods, it is ideal for use in environments where property preservation is essential.
- Effective in closed spaces: Nitrogen is particularly effective in enclosed or hard-to-reach spaces.
The drawbacks of nitrogen
- Extremely cold in liquid form : it can cause burns if the correct PPE is not worn.
- Inert gas: There is a risk of suffocation if used incorrectly or when entering inert spaces. You should always wear an oxygen meter when working with nitrogen.