One of the many advantages of producing your own nitrogen is that you can set the purity level to what your application requires. That is a
major difference to purchased nitrogen, which is always of the highest purity – even though most jobs don't need it. So what affects
nitrogen purity? And why does it matter?
The second question is easy to answer: High-purity nitrogen costs more because it consumes more energy. Therefore, you want to make sure
that you get the purity just right for your application. This is especially true because increasing it beyond what is necessary yields no
additional benefits.
In other words, using nitrogen with a purity of 99.99% for a job that calls for a purity of 99.5% wastes energy and money.
To answer the first question, we first have to look at how nitrogen gas is generated.
Types of nitrogen generators
Two
different technologies are used for the on-site production of nitrogen: pressure swing adsorption (PSA) and membrane. The key ingredient
in each case is compressed air, which contains 78% nitrogen. In the generator, that nitrogen is separated from the rest of the air.
In a PSA
generator,
this happens through adsorption. The generator consists of two separate pressure vessels. One of them is used to filter out the nitrogen
while the other is regenerating.
As the name indicates, a membrane
generator contains
a membrane filled with small, hollow polymer fibers. Not all gases, vapors and contaminants can pass through the membrane fiber wall with
the same ease. This allows the nitrogen gas to be separated from the compressed air. This is called “permeation.”
A PSA generator allows you to produce a nitrogen with a purity of up to 99.999%. It also requires less compressed air. However, the intake
air for the compressor has to be very clean and dry.
The purity a membrane generator can achieve is a bit lower. However, as noted above, most applications do not require the highest purity.
One of the benefits of this technology is that the intake air can contain water vapor.
Factors that impact your nitrogen purity
There are range of factors that could affect purity, some of which depend on the type of generator you use.
The amount of air that flows through the generator is the most important factor. If that intake air volume is too high, it will impact the
nitrogen purity because the pressure in the generator rises too fast. That means that the separating technology of the generator can no
longer keep up. As a rule of thumb, you want to keep you adsorption pressure between 0.6-0.8 Mpa.
An easy solution is to adjust the amount of air that comes from the compressor.
Another factor could be that the intake air contains too many contaminants. This could clog up the molecular sieve, which would have to be
replaced. To prevent this from happening, you can install air treatment equipment such as filters.
However, at some point, the performance of the molecular sieve will diminish, so you should always follow a maintenance schedule.
PSA generators feature a piece of equipment called a solenoid valve. Its failure is most frequently responsible for a decline in nitrogen
purity. When you notice that this purity drops, this is one of the first things you should check.
Where does nitrogen purity matter most?
The purity of your nitrogen is especially important when the nitrogen gas comes into contact with an end product. It matters less if you are
using it for fire suppression or inflating tires. On the other hand, the gas has to be very pure in the food industry or the pharmaceutical
sector. For these and other industrial applications, you need high purity nitrogen.
Many applications are subject to standards that will define the required purity. For example, there are specific requirements for food grade
nitrogen.
Ask the expert
As the expert in air treatment and gas generation, Ash Air knows all about nitrogen purity. If you have any question on how to achieve
the right purity, contact us today. Our experts are happy to help.
Pneumatech gives oxygen to your business. With the PPOG series, Pneumatech offers an attractive replacement for traditional oxygen supply with very interesting returns on investment.
The PPOG1-120 series uses Pressure Swing Adsorption technology to extract oxygen from compressed air, resulting in oxygen purity levels up to 95%.
The PPOG 2-18 HE series is a true game changer in on-site oxygen generation. 30% more efficient than traditional oxygen generators, the PPOG HE gives you the oxygen volume, purity and reliability you need at a massively reduced cost and a smaller environmental footprint.
PSA Oxygen Generators
With the PPOG series, Pneumatech offers an attractive replacement for traditional oxygen supply with very interesting returns on investment.
Discover the inner workings, versatile applications, and numerous benefits of an N2 generator. This revolutionary machine effectively separates nitrogen from compressed air, comprised of 78% N2 and 21% O2. A gas generator stands out as the easiest, most flexible, and economically viable method for securing your own nitrogen supply. Elevate your professional approach and embrace the efficiency and sustainability offered by on-site nitrogen generation, exclusively available in New Zealand.
Who we are and how Ash Air can help your business!
Ash Air has been around in New Zealand since 1979, and we’ve grown into a nationwide company with international support and a
reputation for quality and reliability.We look after all things compressed air for your business!
Rotary Screw and Piston Air Compressors
Vacuum Pumps and Blowers
Nitrogen Generation
An extensive line of Air Treatment components
AIRnet Piping System and Filtration
Mobile Compressors, Generators, and Light Towers
Ash Air's range of Chicago Pneumatic, ALUP, Pneumatech, and Atlas Copco products are used extensively around the world in
industries ranging from oil and gas to food, automotive and farming, and we bring you these world-class compressors here in the land of
the long white cloud.Our technicians are compressed air equipment experts and are dedicated to addressing customer needs. Supported with
nationwide coverage, Ash Air offers one of the widest selections of compressed air, vacuum pump, and industrial gas equipment and parts
available today in New Zealand.
Reliability and Efficiency
With Ash Air, you can count on reliability and high performance for even the most demanding applications. We focus our efforts
on the following:
Increasing uptime
Reducing unexpected repairs
Reducing energy consumption and meeting our sustainability goals
Air compressors come in many types, rotary screw, piston, scroll, reciprocating, some are oil-free and other air compressors require oil
lubrication. Like many businesses, an efficient air compressor is at the heart of their operations. So, which type of compressor should you
choose? What makes a compressor, like a rotary screw, unique? Here are some clear cut benefits of equipping your business with a rotary
screw compressor. Â
Read More…
In the world of compressors, there are often significant and unutilized energy-saving possibilities including energy recovery, pressure
reduction, leakage reduction and optimization of operations through correct choice of a control and regulation system as well as the choice
of compressor size.We are going to take a look at some of the opportunities for minimizing the compressor’s operating costs.Â
Read More…
Many installations that produce compressed air offer significant and frequently unutilized energy
saving possibilities in
the form of waste energy recovery. In large industries, energy costs can amount to 80% of the total cost of compressed
air production.
However, a lot of this energy can be recovered, which in turn will save you a lot of money.Â
Read More…
Liquid water in compressed-air systems can lead to rusted equipment and unresponsive controls. Anyone who uses compressed air will, at some
point, find liquid water in the air distribution system. This can be anything from a nuisance to a serious problem, depending on the
application. If water might corrode equipment or introduce bacteria, removing it is critical.Â
Read More…
Liquid water in compressed-air systems can lead to rusted equipment and unresponsive controls. Anyone who uses compressed air will, at some
point, find liquid water in the air distribution system. This can be anything from a nuisance to a serious problem, depending on the
application. If water might corrode equipment or introduce bacteria, removing it is critical.Â
Read More…
Whenever most people think about a compressor, they probably have a piston compressor in mind. You might already know there are two basic
principles of air compression. One of those is the principle of displacement compression. There are a lot of compressor types that classify
as a displacement compressor. The piston compressor is one of them, oil-lubricated or oil-free.Â
Read More…
Once you have the size and type of
compressor figured out, one last question remains, should I go with an oil lubricated or oil-free air compressor. To not overcomplicate the
answer, your choice should be based on the application and process that the compressed air will be utilized in.
Read More…
Like all compressor types, rotary screw models do require periodic maintenance. Thanks to the simplicity of the internal components,
maintenance is relatively easy on most rotary air compressors. As long as you stick to a rotary screw compressor maintenance schedule, you
will likely be rewarded with many, many years of optimal productivity from your machine.Â
Read More…
Did you know, the biggest part of the air we breathe is nitrogen? Everyone needs oxygen to survive, however air is made up of 78% nitrogen,
only 21% oxygen and tiny amounts of other gases. Although, the human body does not use this nitrogen, it is very helpful in various
industrial applications. There is an unlimited source of nitrogen readily available, allowing you to achieve needed purity at a fraction of
your current annual nitrogen cost.Â
Read More…
If you notice that your compressor is getting hot and bothered, there may be heating issues affecting your air compressors performance. Did
you know that an overheating compressor is top of the pops for being the most common cause of compressor failure.Â
Read More…
A rotary-screw compressor is an air compressor that uses a rotary-type positive-displacement mechanism, typically used replace piston
compressors where large volumes of high-pressure air are needed, either for large industrial applications or to operate high-power air
tools.Â
Read More…
Have a look around and what do you see? What are you thinking about? Your next holiday to Queenstown maybe? You might go snowboarding with
the kids or have some alone time at the Day Spa. Whatever holiday you choose, compressed air is involved in some way, without you even
realising it! Â
Read More…
There are crucial reasons why you should service and maintain your compressor regularly, with the most common issues being piston failure
caused by wear of components, increased friction, corrosion, reduced cooling, overheating bearings and components, clogging of air filters.Â
Read More…
Our passion for energy efficiency and cost saving derives from the concern for our children’s future. Analysing the efficiency of your
system is a brilliant way to start saving.
Read More…
Compressed air is all around us, from the air in a balloon to pumping up tires on your bicycle. In this article we will explain what
compressed air is and how it is created. Whether you know it or not, compressed air is involved in every aspect of our lives, from the
balloons at your birthday party to the air in the tires of our cars and bicycles. It was probably even used when making the phone, tablet or
computer you’re viewing this on.Â
Read More…
One of the biggest challenges is to correctly size your new air compressor. Similarly to everything else, new compressors available on the
market are more efficient and employ better technology, therefore you have to understand the application and usage to size the machine
correctly. Choosing the wrong air compressor for your facility can lead to problems with production and or increased costs due to wasted
energy.Â
Read More…
Once you have the size of the air compressor figured out, the
next thing to do is to decide on the type of compresor you will need for your application - piston, rotary screw compressor etc. Let us take
a look at two of the most popular options available. When choosing the right type of compressor, you should ask yourself the following
questions:
Read More…
​Which vacuum pump do I need? - this is one of the most frequent questions we receive and this is understandable, because there are number
of technologies which can provide the same vacuum level and pumping speed. Here is quick advice on how to choose the best vacuum pump for
your needs.Â
Read More…
You may be asking, why does my air compressor start, then stop? Allow us to take the guessing out of it. We understand your pain. We know
that a compressor problem can quickly result in hours (if not days) of production downtime and loss of revenue. When your compressor
continuously shuts off from on, we refer that as a short cycle. There are a few reasons that a short cycle may be happening with your
compressor.Â
Read More…
Air compressor leaks are very common in all applications, but can be very costly and difficult to find. On average, 20-30% of the compressed
air used in a manufacturing plant is wasted as leaked air. Finding and fixing these leaks can save your business thousands of wasted dollars
a year.Â
Read More…
When installing a compressed air system into a business, people often look to PVC piping as an option to build a piping system because it is
cheap, versatile and easy to install. However, using PVC pipe in any compressed air application is extremely dangerous and NOT recommended
by multiple associations and manufacturers.Â
Read More…
Changing the oil and oil filters on your compressor is one of the most common routine maintenance tasks to perform to keep your compressor
running efficiently. After you remove your old oil and oil filter, you may find yourself wondering, “Where do I dispose of these?”, or “Can I
just throw them in the trash?”. Because oil is toxic and a pollutant, disposing of your old oil and filters is not as simple as just tossing
them in the trash.Â
Read More…
Two
different technologies are used for the on-site production of nitrogen: pressure swing adsorption (PSA) and membrane. The key ingredient
in each case is compressed air, which contains 78% nitrogen. In the generator, that nitrogen is separated from the rest of the air.
