In this article you’ll learn how nitrogen gas is supplied for industrial uses, and the reasons why using nitrogen gas generators has become the preferred method.
The Worldwide Demand for Industrial Gases
Industrial gases include elements and compounds that can be found in the atmosphere such as nitrogen, oxygen, hydrogen and carbon dioxide. It can also include gases that are synthesized or produced by separation such as acetylene, nitrous oxide, carbon monoxide, helium etc.
There are a large number of industries where industrial gases are used to operate machinery or provide suitable environments for other chemicals to exist or for chemical processes to occur. And since there are multiple types of industrial gases, they are in demand for their unique physical and chemical properties in ways that can’t be easily substituted. Here’s a brief list of how industries use these gases:
- Chemical manufacturing applications such as petrochemical and fertilizer production
- Steel manufacturing and metal fabrication applications like welding and metal cutting
- Healthcare and medical equipment where certain procedures and test require these gases
- Electronics manufacturing such as semiconductors, circuit boards, flat panels, solar panels etc.
- Food & Beverage production requiring carbonation and for food preservation
- Water treatment applications like lowering PH levels, disinfection, growth of aquaculture etc.
These are just a few of the ways in which they are used but we can’t overstate the demand for industrial gases as they support economic segments that make up a significant portion of the world’s GDP.
For the purposes of this article, we’re focusing only on Nitrogen and how it is supplied to industrial plants and facilities.
The Drawbacks Of Using Industrial Gas Cylinders To Meet The Demand
Nitrogen Gas is supplied in two ways: either nitrogen gas cylinders or on-site nitrogen generators.
Gas cylinders come in different sizes with the maximum height being a little above 1.5 meters and a maximum weight that’s upwards of 80 kg. Gas drums can weigh as much as 700 kg. Delivery of the cylinders to the facility usually happens by truck where they are stationed upright within a container unit that can hold multiple cylinders.
These cylinders need to be off-loaded by forklift and placed in a detached storage space with plenty of ventilation away from the main production area. The storage space should be at a safe distance from sources of heat, from staircases or elevators, and major routes of traffic. The temperature within the storage space shouldn’t exceed 51°C.
Using Nitrogen gas cylinders requires less starting capital and almost no maintenance when compared with using a gas generator. Gas cylinder bundles are purchased on rent with a minimum of three cylinders required on-site at all times – one being used, one waiting to be used, and one empty cylinder waiting to be replaced. But renting cylinders becomes less cost efficient over time, especially if the facility increases production capacity. They take up a large amount of valuable floor space, create a safety hazard, and require special handling due to their weight. And there are estimates that say up to 14% of gas inside cylinders is left inaccessible once the pressure in the cylinder drops past a certain level.
Why On-Site Gas Generators are an Improvement Over Cylinders
When production requirements increase the rental fees and storage requirements of industrial gas cylinders becomes impractical – you’re going to have to pay more and find more space. More cylinders mean more exposure to risk, from contaminants entering cylinder valves and inconsistent purity levels across the cylinder bundles you’ve rented. You will also find that the downtime of loading and unloading or fitting and un-fitting nitrogen gas cylinders adds up significantly.
That’s why gas generators have emerged as the go-to solution for large scale industrial applications. Approximately 78% of atmospheric air contains nitrogen and 21% contains oxygen. Nitrogen gas generators use air compressor technology to extract nitrogen from atmospheric air. Within the generator compressed air will be subject to techniques of separation, which can be either pressure swing adsorption or selective membrane permeation.
This Chart Compares the Outcomes of both Separation Techniques:
The benefits of switching from nitrogen gas cylinders to nitrogen gas compressors are:
- Access to the higher purity levels of Nitrogen which can be anywhere from 95% to 99.999% nitrogen.
- More control over the flow rate and pressure you need from the nitrogen supply.
- Increase in overall up-time because of the constant supply of nitrogen.
- Reduced Nitrogen wastage, which is a common problem of nitrogen gas cylinder supply.
- Decreased risks involving transportation, storage, and maintenance cylinders.
- Significant cost savings because an on-site nitrogen generator will pay for itself in about 2 years or less.
Despite the benefits some plant managers continue to rely on nitrogen gas cylinder suppliers for a variety of reasons. A lot of the time they would rather stick to what they know and would prefer to avoid the initial capital investment of installing a nitrogen gas generator system.
But what they might not be aware of is that air compressor manufacturers like Atlas Copco are making it much easier to switch to Nitrogen gas generators. They create lease-to-own programs where the terms are flexible and monthly payments are low, specifically to address this concern. You could even request an energy efficiency audit of your installation so that you design a nitrogen gas generator system that offers maximum energy savings.
Dealing with the manufacturer directly over email or phone is the best way to ensure that you build a nitrogen gas generator system that is personalized to your needs and outperforms a gas cylinder supply system. And as your production requirements increase switching over to an N2 gas generator becomes a priority as you are essentially incurring more losses than necessary.