How to make Cold Compressed Air

Air is freely available everywhere, while compressed air isn’t. What is compressed air, and what happens to it when it’s compressed?

All human beings need air, including oxygen, to survive. Engines and electronics also require air for their proper functioning and operation. Compressed air is a standard tool to work in electronics, factories, and manufacturing plants. The forced air comes in handy to remove dust from mouses, keyboards, monitors, and other equipment.

The air plays a vital role but isn’t quite the same as the air we breathe. Compressed air is used as a power source to energize tools and engines. Have you noticed the reaction that occurs when the air comes out of the straw? The atmosphere is cold!

Why is compressed air cool?

It’s not a chemical reaction; it’s about the kinetic of gases. Anyone who ever used compressed air can testify how cold it gets. After all, it comes with frostbite warnings for a reason!

Canned air doesn’t have the same components as atmospheric air. It’s composed of a mixture of nitrogen and other harmless compressed gases. When we compress air, we force molecules closer together. They’re the same molecules as atmospheric air but take less space.

Forcing gas molecules together in a given volume offers a wide range of side effects when the molecules increase in a given volume, the mass and density increase. When both mass and density increase, the pressure of air also increases to create compressed air.

The secret behind cold compressed air lies within how the gas expands, which refers to Adiabatic Expansion. Gas needs the energy to expand. The power is taken from the gas remaining in the can, which cools significantly as the pressure exits. As more gas leaves, the remaining molecules are slower and slower, simultaneously creating a colder temperature. Under the accurate circumstance, the gas can even condense and freeze.

Compressed air cans

Contrary to its name, compressed air cans do not contain air but instead hold easily compressible gases to reach a liquid state. Because these gases are compressed up to 70psi to achieve a liquid form, the compression allows a substantial amount of gas to fit in a relatively small space. Consequently, when the gas is released into a large area, it rapidly expands.

Movement of compressed air energy

The evaporation of liquid inside a can result in a significant heat drop and thus absorbs a large amount of heat from its surroundings – in this case, the metallic can. When the liquid inside captivates the heat from the metals’ core, it rapidly cools down. It will also absorb energy from anything it touches. For example, you’ll often see a thin layer of frost form on your keyboard after its first use.

Compressed air can be compared to the fourth utility. Although not as vital as electricity and petroleum, compressed air plays a fundamental role in our day-to-day. Although you might not realize it, most products that we use today use compressed air to operate.

See our line up of pneumatic air cooling vortex tubes here and discover how you use cold compressed air in your applications.