Nitrogen gas is the unsung hero of modern laboratory operations, quietly enabling countless analytical procedures, protecting sensitive equipment, and maintaining the inert atmospheres essential for accurate scientific work. Yet despite its critical importance, many laboratory managers struggle with selecting the optimal nitrogen supply method for their facility's unique needs.
The choice between traditional cylinder delivery, bulk liquid supply, or on-site generation can significantly impact your laboratory's operational efficiency, costs, and research capabilities. This blog explores each supply method in detail, helping you make an informed decision that aligns with your laboratory's requirements and long-term goals.
Understanding Laboratory Nitrogen Demand
Before diving into supply methods, it's essential to understand why laboratories consume such substantial quantities of nitrogen. Modern analytical instruments are increasingly nitrogen-hungry, with applications ranging from liquid chromatography-mass spectrometry (LC-MS) systems that require continuous gas flow to maintain optimal performance, to nuclear magnetic resonance (NMR) spectroscopy equipment that depends on nitrogen for cooling and atmospheric control.
Beyond instrumentation, nitrogen serves critical roles in sample preparation, where it prevents oxidation during reactions, and in maintaining inert atmospheres within gloveboxes used for handling air-sensitive materials. The gas also protects valuable cell cultures in incubators and ensures proper atmospheric conditions in fume hoods, making it indispensable across virtually every laboratory discipline.
While Organomation sample concentrators are more conservative when it comes to nitrogen consumption, nitrogen is the driving force in blowdown evaporation.
Traditional Cylinder Supply: The Familiar Choice
Cylinders of nitrogen gas have long been the default choice for laboratory nitrogen supply, and for good reason. These high-pressure vessels offer immediate availability, require minimal infrastructure investment, and provide flexibility for laboratories with variable or seasonal nitrogen demands.
The Cylinder Advantage
Cylinder supply excels in situations where nitrogen usage is intermittent or unpredictable. Small research facilities, teaching laboratories, and specialized testing facilities often find cylinders perfectly adequate for their needs. The system requires no upfront capital investment in generation equipment, and maintenance responsibilities rest entirely with the gas supplier.
Hidden Costs and Operational Challenges
However, the apparent simplicity of cylinder supply masks several significant drawbacks. The per-unit cost of nitrogen from cylinders is substantially higher than other supply methods, particularly when factoring in delivery charges, cylinder rental fees, and administrative overhead. More critically, cylinders introduce operational risks that can disrupt research workflows.
Running out of nitrogen mid-analysis can invalidate hours of work and potentially damage sensitive samples. The physical handling of heavy cylinders presents safety risks, while the need for regular ordering and delivery coordination creates administrative burden. Additionally, cylinder storage requires dedicated space and proper ventilation, reducing available laboratory real estate.
Bulk Liquid Supply: Scaling Up Efficiency
For laboratories with substantial nitrogen consumption, bulk liquid supply offers a compelling middle ground between cylinders and on-site generation. This approach involves storing nitrogen in liquid form in large tanks, then vaporizing it to gas as needed and distributing it throughout the facility via permanent piping. While liquid nitrogen dewars can be placed outside of a building, they are also stored in warehouse storage or dedicated rooms as well.
Economic and Operational Benefits
Bulk liquid supply dramatically reduces the per-unit cost of nitrogen compared to cylinders, making it economically attractive for high-volume users. The system eliminates the constant cycle of cylinder changes, reducing both labor costs and operational disruptions. Large storage capacity means fewer deliveries and greater supply security.
Infrastructure Requirements and Limitations
The transition to bulk liquid supply requires significant infrastructure investment, including outdoor storage tanks, vaporization equipment, and internal distribution piping. Facilities must have adequate outdoor space for tank placement and comply with safety regulations governing cryogenic liquid storage.
On-Site Nitrogen Generation: The Modern Solution
On-site nitrogen generators represent the cutting edge of laboratory gas supply, offering unprecedented control, cost-effectiveness, and operational reliability. These systems produce nitrogen gas directly from ambient air, eliminating external dependencies while providing unlimited supply capacity.
Pressure Swing Adsorption Technology
Pressure Swing Adsorption (PSA) generators utilize specialized adsorbent materials, typically carbon molecular sieves, to separate nitrogen from compressed air. The process operates through cyclical pressurization and depressurization, with adsorbent beds alternately capturing oxygen and other gases while allowing nitrogen to pass through.
PSA technology excels in applications requiring high purity nitrogen, capable of producing gas with purity levels up to 99.999%. This makes PSA nitrogen generators ideal for critical analytical applications, pharmaceutical manufacturing, and research requiring ultra-pure atmospheres. The technology offers excellent energy efficiency and can be precisely tuned to match specific purity requirements.
Membrane Separation Technology
Membrane nitrogen generators employ semi-permeable hollow fiber membranes that exploit the different permeation rates of atmospheric gases. Oxygen, water vapor, and carbon dioxide pass through the membrane walls more rapidly than nitrogen, effectively concentrating nitrogen in the non-permeate stream.
While membrane technology typically produces nitrogen with purity levels up to 99.5%, it offers several advantages including lower maintenance requirements, simpler operation, and excellent reliability. Membrane generators are particularly well-suited for applications where ultra-high purity isn't critical, such as general laboratory atmospheres, packaging applications, and routine analytical work.
How Should Nitrogen be Supplied to your Lab?
Selecting the right nitrogen supply method represents a strategic decision that will impact your laboratory's operations for years to come. While the initial analysis may seem complex, the long-term benefits of choosing the optimal solution far outweigh the effort required for proper evaluation.
Consider engaging with multiple suppliers to obtain detailed proposals and cost analyses based on your specific requirements. Many suppliers offer trial periods or pilot programs that allow hands-on evaluation of different technologies before making final commitments.
Remember that the lowest initial cost rarely represents the best long-term value. Focus on total cost of ownership, operational reliability, and alignment with your laboratory's research mission when making your final decision.
The investment in proper nitrogen supply infrastructure pays dividends in improved research capabilities, reduced operational stress, and enhanced scientific productivity. Choose wisely, and your laboratory will benefit from reliable, cost-effective nitrogen supply for years to come.
Luckily, Organomation offers several tools to help make the analysis and task of product selection easier:
- Is renting nitrogen gas cylinders too expensive?