Buying Guide for Energy Efficient Air Compressors

The most important thing about an industrial air compressor is air, i.e., the air that goes into the compressor and compressed air that goes outside the compressor and then to your industrial applications. For the compressed air to meet ISO 8573-1 quality standard, the air that goes in the plant/process should be as clean as possible and free of any smoke or dust particles. You can use a pre-filter if your industrial plant is situated at a location where the dust concentration in the atmosphere is high.

The choice of an oil-injected or oil-free air compressor depends upon the air demand of your industrial applications. Similarly, the required pressure and flow rate of compressed air for plant equipment determine the optimal size of the air compressor that you should buy. In the same way, compressed air usage pattern and air consumption of the end machine determines the type of compressor either fixed speed or variable speed. All these things need to be catered accordingly by choosing an appropriate energy-efficient air compressor.

The distance from the air compressor and the end machine should be kept as minimal as possible for energy-saving purposes. It is advised that the air compressor should be placed in the central region of the plant to transfer compressed air easily to all industrial equipment. This would save you from any unwanted pressure losses during the transfer of compressed air, making your business cost-efficient. Energy audits and walk-the-line compressed air assessment tests can also help you analyze the energy efficiency and optimal distance of your air compressor from the industrial equipment.

Air compressors are usually placed inside a closed confined space within the facility premises known as a compressor room. One of the many things you should consider while buying an air compressor is the features of the compressor room. A compressor room with ideal characteristics would help in saving your industrial air compressor from wear and tear by protecting it from undesirable weather conditions. The compressor room should have an efficient ventilation system that helps in dissipating heat energy.

You can also invest in an energy recovery system and use this heat in other applications. The compressor room should be designed such that the air coming in the room and then to the compressor is as clean as possible. The volume of atmospheric air coming inside the compressor room should be enough to limit temperature rises till 7-10°C with a maximum air velocity of 4 m/s. An ideal location for your compressor room would help in improving the operating economy of your air compressor by decreasing fluctuations in its working pressure.

You should be devoting enough time to figure out the optimal pipeline distribution system for your air compressor before purchasing it. An ideal piping system would prevent pressure losses by maintaining the flow of compressed air and minimizing throttling effects across your facility. For starters, draw a diagram of the distribution network of compressed air. A closed-loop pipeline system with a network of risers, distribution pipes, and service pipes would be ideal.

The consumption points in your facility should be grouped in logical units and then supplied by compressed air accordingly to maximize efficiency. Besides, the length and diameter of pipes should be properly calculated to minimize friction and pressure losses.

The compressor's intake air must be clean and free of solid and gaseous contamination. Particles of dirt that cause wear and corrosive gases can be particularly damaging. A pre-filter (cyclone, panel or rotary band filter) should be used in installations where the surrounding air has a high dust concentration. In such cases, the pressure drop caused by the pre-filter must be accounted for during design. It is also beneficial for the intake air to be cold. It may, therefore, be appropriate to route this air through a separate pipe from the outside of the building into the compressor.

It can be critical for several installations to remain operational at higher/lower temperatures. So, what kind of compressed air installation is the best fit for your plant? And what effect does the ambient temperature have on your compressor and compressed air installation? When the compressor draws in ambient air at a significantly higher ambient temperature, the installation has to work harder (i.e. more rotations/loaded hours) to produce the same quantity in Nm³. Think of it as a balloon that you have inflated. Leave it in the sun and it will expand; leave it in a refrigerator and it will shrink. To produce the same volume, you would have to inflate more balloons in the sun.