What Is Compressed Air Condensate?
Compressed air systems are crucial to a broad range of industrial applications, from automotive to aerospace. As the air is compressed, its water vapour can turn into condensation. If too much of this condensation makes its way through your system, it causes wear and tear to valves and cylinders. You also risk reducing the quality of your end products or services.
In oil-injected compressors, the condensate can also contain minuscule oil droplets and particulate matter. These contaminants may be invisible to the naked eye, but they can wreak havoc on your equipment and the environment if handled or disposed of without air treatment.
Whether you use an oil-injected or oil-free air compressor, high moisture levels can and will degrade your equipment and potentially even put you at risk of breaking the law. This guide will tell you exactly what condensate is, how it forms, the risks of neglecting it, and what you can do about it. We will also discuss the many benefits of proper condensate management and dealing with compressor condensate effectively.
At Search Air, we have been an industry-leading supplier and installer of compressed air systems for over 75 years. If you need a compressed air audit, we are only a phone call away – condensate and contamination are just some of the costly and dangerous issues we can identify. Alternatively, we also supply a range of the most advanced Atlas Copco UK solutions available, equipped with sophisticated water and oil separators that can minimise the risks associated with condensate while improving efficiency and productivity in your workplace.
Call us today to learn more about our energy-saving solutions. Keep reading to learn everything you need to know about compressed air condensate management.
Understanding Compressed Air Condensate
Compressor condensate is a liquid by-product created during the air compression process. Oil-injected compressors release condensate that mostly contains water but can also contain microscopic contaminants and oil particles (forming an emulsion). So, where does this water come from?
Ambient air in the atmosphere contains a certain amount of moisture, which makes its way into your compressor as the air is pulled into the system through the inlet valve. When the compressor pulls in air or gas, it brings this humidity with it. Moisture in air turns into condensate when it reaches a certain temperature, known as the pressure dew point (PDP). When air reaches the PDP, it can no longer hold water vapour and turns into a liquid state called condensation.
This process occurs naturally. As the compressed air cools in the aftercooler or piping, it forces water vapour to condense into liquid form.
In air compressors, the compression process also causes the air to release condensate in addition to the heating process. For example, if your system works at a pressure of 7 bar(e), it reduces the incoming air to seven-eighths of its original volume, reducing the air’s ability to hold moisture by seven-eighths. Your compressor system is fitted with equipment to release this moisture but can rarely eliminate 100% of it.
What Is Compressed Air Condensate?
How Much Condensate is Produced?
The amount of condensate released by a compressor is surprisingly high. A 100 kW system operating with air at 20 degrees Celsius and 60% humidity can release around 85 litres of water over eight hours. The higher the air temperature, the more condensate is produced due to humid air. For example, a 55 kW compressor operating at 24 degrees Celsius with 75% humidity can produce up to 280 litres daily.
By law, you are required to remove, manage, and dispose of condensate responsibly. Fortunately, properly managing condensate is advantageous for more reasons than just compliance.
Why Is Condensate Management Important?
Responsible compressor condensate management is crucial for a host of reasons, namely:
Environmental Impact
Condensate can contain microscopic traces of contaminants such as oil that, while not visible, can damage the environment. Because the condensate contains moisture or oil, it is often classified as hazardous waste. If discharged without first being treated, condensate from compressors can reduce soil quality, contaminate water supplies, and even harm local habitats.
Equipment Longevity
Poor condensate management systems can lead to too much moisture working its way through your air compressor system, which can lead to corrosion not only of the system itself but also of all the pneumatic tools and equipment connected to it. Effective removal ensures consistent air quality and prevents rust in your receiver tank.
Energy Efficiency
Mismanaged condensate can reduce the efficiency of your air systems, often causing users to increase pressure levels to achieve their desired result. This not only drives up energy costs but also prevents you from taking advantage of energy recovery opportunities that could significantly reduce waste and boost system performance. Using smart, zero-loss drain valves ensures you don’t waste expensive compressed air during drainage.
Compliance
Businesses in heavy industries must comply with stringent regulations to protect the environment. Standards such as ISO 8573 set out minimum requirements for air purity, including the safe removal and correct treatment of condensate.
In the UK, strict environmental regulations (such as the Water Resources Act 1991) mean that condensate must be treated before disposal. You cannot simply pour oil-laden water down the sink. Compliance issues can result in unlimited fines, which could tarnish a company’s reputation and consume a significant chunk of its revenue.
How to Manage Compressed Air Condensate
The best way to find out how to properly manage condensate is to book an air compressor audit with our experts, who can identify inefficiencies and compliance issues before they become costly. To optimise your compressed air system, here is what you can do in the meantime:
Inspect Your System
Start by visually inspecting your system as condensate drains to see where it is being directed. Make sure to check all the compressors, air dryers, air receivers, and filters. If your condensate is simply being directed to the floor or into simple containers, you will need to treat the water before you can dispose of it to comply with the law. Be aware that in winter, external pipework can freeze, leading to blockages within the system.
Install Oil and Water Separators
Ideally, the condensate from your compressed air system should be piped into a quality water separator (such as the Atlas Copco OSC series). These oil-water separators use advanced filtration (like oleophilic filters and activated carbon) to treat the mix of water and oil.
These separators treat the condensate so that it can be simply drained into the foul water drain (NOT the rainwater or stormwater drains) without harming the environment. Remember that you may need permission from your local water authority before draining your treated condensate.
Upgrade Your Drains
Old manual or timer drains can be inefficient. We recommend upgrading to electronic zero-loss drains (like the Atlas Copco EWD). These intelligent drains monitor fluid levels and only open when necessary, preventing the loss of valuable compressed air.
FAQ
Is compressed air condensate hazardous waste?
Yes, if it comes from an oil-injected compressor, the condensate is contaminated with oil and is classified as hazardous waste. It must be treated to reduce oil content (typically to below 20 ppm) before the water can be discharged.
What happens if I don’t drain my compressor tank?
Failure to drain the tank allows water to accumulate, reducing the tank’s storage capacity. This leads to corrosion, rust particles entering the airstream, and potential damage to downstream equipment like the drying system.
How do I choose the right air condensate solution?
You must consider the volume of condensate your system produces, the type of oil used (mineral vs. synthetic), and your local discharge regulations. Contacting a specialist to assess your air treatment needs is the safest route.
Learn More about Compressed Air Condensate Management
If you need new oil-water separators to keep your systems in full working condition and your business on the right side of the law, we can help. At Search Air, we have been a leading supplier of advanced compressed air equipment for the better part of eight decades. We were also named the Atlas Copco Distributor of the Year in 2022, so you can trust us for honest advice and recommendations. Call us today to learn more about our effective and efficient separators and compressed air dryers. Unsure what you need? Book an audit at a time that works with your busy schedule.