How to Choose an Inline Filter for Your Compressed Air System?
Picking out an inline filter is not an art, but it could be confusing if we do not ask the right questions or understand the process that
requires filtration. Before we move any further, let’s take a step back and get a general idea of filtration and why it plays an
important role within the compressed air system.
Why do you need a filter?
choosing a filter to dry the compressed air
When you have a taste for coffee, it is simple to go to your nearest coffee bar or use a popular ‘cup’ machine, but we want more. The
example I’d like to use consists of using the drip coffeemaker and roasted beans. One of the most important items in making a good cup
of coffee in such machine is to use a proper filter in order to avoid a cup full of grainy particles and any other remaining pieces of
the coffee bean. As insignificant as it might seem, the paper filter plays a vital role in making coffee that you can enjoy.
Although, a different entity than a coffeemaker, your compressed air system needs a filter as well. As we have learned in past articles,
compressed air is full of particles, aerosols and oil vapors (in oil injected pistons and screws) that contaminate the compressed air
and can cause potential harm to its end users (equipment that uses compressed air). Incorporating the correct inline filter can help you
eliminate the unwanted particulates as well as aerosols and vapors. The amount of filters and types needed will be dependent on the
quality of air your application and or process requires. Let’s take a look at the different types of filters and the questions that will
help you choose the correct filter.
How clean does my air need to be?
In order to understand how clean your air needs to be, you have to identify and assess the application and process that utilizes the compressed air. Not
all applications and processes that use compressed air require the same level of filtration, which is why having this information is the first step
in choosing the correct filter. Compressed air utilized for pneumatic purposes can oftentimes be supported by a standard dry particulate filter that
provides filtration down to 1 or 0.01 micron, however, if your process requires an OSHA-approval and elimination of oil vapors, then a charcoal activated
filter will have to be utilized. Let us get a better understanding of what contaminants are and how they affect compressed air system. Contaminants
within a compressed air system can originate from ambient air that is utilized, as well as the system (compressor) itself. There are three main contaminants
that are found in compressed air: particulates, aerosols and vapors.
Particulates: Particulates in compressed air system are small pieces of solid material such as dust, dirt and or pollen from the ambient air, as
well as loose metal particles that can be caused by pipe corrosion. Depending on the sensitivity of your application and or process, contact with particles
can be damaging to the end product, therefore causing delays in production and quality control issues, not to mention potentially unsatisfied customers.
Aerosols: Aerosols consist of small droplets of liquid that can be found within compressed air system, especially in those using oil-injected compressors.
Aerosols are created from the lubricant, in this case, the oil used in the compressor and can be harmful to both products and people if not treated
properly.
Vapors: In the compressed air system, vapors consist of lubricants as well as any other liquid that has converted to a gas. Such vapors require a special
carbon activated filter in order to be removed from the system.
Now that we have a better understanding of the contaminants above, let us take a look at what types of filtration methods are used in eliminating each
type of contaminant.
Removing dry particulates
There are three main mechanisms that are utilized in dry particulate filters to remove solid particles of all sizes out of compressed air.
Inertial Impaction: Inertial impaction is a process where particles that are too heavy to flow with the compressed air stream get trapped in the fiber
media. The larger the particles are, the easier it will be to separate them.
Interception: Smaller particles can follow the airstream, but if the diameter of the particle is larger than the gap of the filtermedia, it will
get caught by the filter media, making it easier to eliminate larger particles than smaller ones.
Diffusion: Diffusion happens when small particles move erratically throughout the surface, instead of following the compressed air stream. This
irregular movement path is caused by the particles colliding with other gas particles, an occurrence called Brownian movement. Since the particles
have a free range of motion and can move around freely, it is much easier to and more likely that they get intercepted by the filter media and removed
from the compressed air stream. Through diffusion, separation of smaller particles is easier than separating larger ones.
These three forces contribute to the overall efficiency of the filter.
Removing aerosols and vapors
There are two types of filters used to remove aerosols and vapor. The coalescing filters are utilized to remove liquids as well as some particulates, while
vapor filters use adsorption to remove vapors from compressed air.
Coalescing: Coalescing filters are used to remove aerosols and particulates, but are not effective in the removal of vapors. The coalescing process consists
of bringing small droplets of liquid together in order to form large droplets. As the droplets increase in size, they fall from the filter into a moisture
trap, resulting in a cleaner and dryer compressed air stream.
Adsorption: Adsorption is a chemical process is used to remove gaseous lubricants or vapors. The process consists of vapors bonding with the surface of
the media (adsorbent), which commonly uses activated charcoal in the filters due to its high surface area and attraction to the oil vapor. As the oil
vapor covers the surface of the activated charcoal over time, it is essential to change it before it is fully saturated. If not, this would lead to
a breakthrough of the oil into the air system. It is also necessary to use a dust filter after the activated charcoal filter, since small charcoal
particals could break out and enter the airstream.
Can my process be damaged by lubricants like oil?
In order to assess the potential damage that oil can cause within your compressed air system, you have to understand the basic requirements for your industry
or equipment that uses the compressed air. If your industry has strict health codes and or your equipment is sensitive to oil or vapor exposure, it
is crucial to use proper filtration. Let’s take a closer look at lubricants and understand the effects they can have on your end product.
Similar to particulates, lubricants can enter your compressed air system from ambient air as well as from the compressor itself. Facility operations, like
a motor exhaust releases hydrocarbons like oil aerosols into the ambient air, which can compromise air quality and cause equipment failure. Oil injected
air compressors will also release lubricants into the compressed air system, resulting in increased operational and maintenance costs. Industries such
as electronics and semiconductor are especially exposed to lubricant contamination, which can result in product loss, missed deadlines and unsatisfied
customers.
Poor filtration is oftentimes leads to pipe corrosion, increased pressure drops and can cause equipment damage, resulting in costly downtime and unexpected
repair costs. Corrosion can also cause excess debris in your piping system, which in turn results in your compressor working harder, leading to higher
energy consumption and excess ware on compressor parts. Proper filtration is key in achieving desired results when strict codes or purity classes are
enforced.
The only way to protect your product fully from unwanted oil in your compressed air system is to utilize oil-free compressors, as this type of technology
will eliminate the risk of contamination, resulting i clean, high quality compressed air.
Be sure to check out our online shop, where we have a range of Inline Filters to suit your needs:
Do you have an idea for our #expertcorner? Let
us know!
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!
Reciprocating, Screw, air compressors
Vacuum pumps
Nitrogen
An extensive line of air treatment components
Ash Air's range of Chicago Pneumatic, Alup, Pneumatech, and Quincy compressors 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 by a 13 locations
nationwide, Ash Air offers one of the widest selections of compressed air equipment and parts available today in New Zealand.
Reliability and Efficiency
With Ash Air compressors, you can count on reliability and high performance for even the most demanding applications. We focus our
efforts on the following:
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.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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!
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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.
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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.
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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.
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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.
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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:
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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.
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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.
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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.
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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.
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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.
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