hit the road jack

Hit the road Jack: when to move your compressed air system outdoors

The most dangerous words in compressed air are, “That’s what we’ve always done before”. Sometimes you need to take a step back to gain perspective. When it comes to installing a compressed air system, many get fixated on the idea of a compressor room. While it usually makes sense to install equipment inside, there are certain situations when it’s not a good idea. If your compressed air system will be exposed to extreme temperatures, excessive dirt/dust or corrosive chemicals, or is in a Classified Area, it may be best to hit the road and move the installation outdoors.

Extreme temperature

Extreme temperatures indoors? Is that even possible? Definitely. If the only place for the compressor room is next to the boiler room or (in the case of food processing) next to the area that’s essentially a plant-sized refrigerator, then think twice about placing compressed air equipment in that room.
Excessive heat can result in high approach temperatures which reduces the cooling efficiency of the aftercooler and creates excess condensate for any downstream air treatment components. It can also reduce lubricant life, causing equipment to overheat and shutdown.
Low temperatures can impede lubricant flow, causing cold starts. Cold starts can result in unnecessary wear and tear on the motor and airend and in extreme cases, lead to catastrophic failure. Low temperatures can also promote excess moisture in control lines and other components. If the temperatures falls too low, this condensate can even freeze.

Excessive contaminants

The ambient air in a compressor room is naturally filled with contaminants: particulates such as dust, oil such as lubricant aerosols vented from equipment, and moisture. All of these contaminants are ingested into the compressor, magnified during the compression process, passed on to the rest of the system, and without proper filtration, to the end process. If your plant process creates additional contaminants, such as dust in a cement plant, then you may want to look at an alternative solution. Here’s an example of a dryer installed in one of those environments:

dirty and dusty dryer

Classified areas

In the past, “Hazardous Location” was used for equipment installed in chemical plants, refineries, or drilling platforms. Now, this terminology appears in sugar mills, grain storage facilities, and anywhere there might be flammable liquids, gasses, or dust present. Hazardous areas are defined as areas where the presence of flammable gases or liquids, combustible dusts, or easily ignited fibers exist in sufficient concentrations to cause a fire or explosion, provided a source of ignition.
While it is possible to customize equipment so it is explosion proof, quite often the cost to do so is incredibly high. It’s considerably less to install the equipment outside in an enclosed system and add the extra hundred feet of piping needed to reach the process.
If you have any or all of these conditions in your plant, then consider moving your compressed air system outdoors. You’ll have the potential to increase uptime, reduce maintenance costs, and keep energy efficiency high.

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