Nitrogen is commonly used in food and pharmaceutical industries for processes like gas chromatography and sample drying. Facility managers can invest in compressed gas tanks or an in-house nitrogen generator for supply of nitrogen gas.
High pressure gas cylinders are used to store liquid nitrogen. Liquid nitrogen is the liquefied version of nitrogen gas and is stored at atmospheric pressure and subzero temperature. There are hazards and safety risks involved in the storage of nitrogen this way. The use of nitrogen generators quells these safety concerns as they provide a continuous supply of pure nitrogen from compressed air and are easily adjustable.
Hazards of Liquid Nitrogen
Using gas cylinders for nitrogen storage can increase the risk that employees experience detrimental health effects.
Compressed-gas tanks store tanks at high pressure. If an accident occurs and the tank is compromised in any way, gaseous nitrogen displaces the oxygen in the air. An oxygen-deficient atmosphere is hazardous, especially if the area is small and enclosed. Employees may be asphyxiated with diminished oxygen supply. They may experience changes in normal function, effects on physical and intellectual performance, and even fainting or unconsciousness.
At low temperatures, the gas could cause frostbite and breathing discomfort. Employees converting liquid nitrogen into nitrogen gas could experience cold burns if the nitrogen comes in contact with unprotected skin.
Safe Work Practices
Facility managers need to consider the task being performed and liquid nitrogen quantities involved when laying out safe work practices. The lower the oxygen levels contained in a nitrogen tank, the more control measures should be in place to mitigate risk. This may involve use of signage, written procedures, and training. Other more severe control measures include emergency stop buttons, immediate evacuations, mechanical ventilators, CCTV cameras, and stricter rules of access.
Use of a Nitrogen Generator
In-house nitrogen generators are designed to remove various particles of matter from the air to provide pure nitrogen gas. They extract the desired nitrogen from the air. The creation of nitrogen in this way is much safer than that required by compressed gas tanks. Nitrogen generators promote facility safety and reduce risks for asphyxiation and frostbite.
Generators are meant to supply gas only at the specific pressure and flow rate necessary for an operation. These are specifications that can be adjusted at any time. As such, the risk of an accident and exposure to reduced levels of oxygen is limited.
In addition, nitrogen generation is convenient. With liquid tanks, employees need to ensure adequate available gas supply. It can be inconvenient and difficult to replace tanks on a regular basis. However, the generation process can easily provide necessary gas without additional hassles.
Facility managers face reduced costs when they invest in nitrogen generators. There are no additional costs beyond electricity use and regular maintenance. On the other hand, compressed tanks require expenses related to regular replacement and inventory control.
Nitrogen generators are generally preferred over compressed tanks because they mitigate the risks involved with handling nitrogen and are more cost-efficient in the long run.