During my visit to Asia, I was confronted with again the daily reality.

We all talk about climate change and the disaster it is becoming. Indeed, no explanation needed to illustrate the floodings, the melting of the Ice caps etc…

At the same time, in the Compressed Air world, little changes.

I witnessed again, typical normal installations, where multiple Oil flooded screw compressors were installed. In one case 5 machines, which all were sold based on low price and good performance 6kW/M3/min. Honestly, 6kW/m3/min is relatively ok. 

The standard should be 5-6kW/m3/min @ 7bar at full load and PARTIAL load !

 However, due to the high ambient temperatures, the user was complaining about the high oil consumption, frequent service intervals and break-downs, resulting in high operational costs. The amount of waste generated by the Oil filters and the oil carry over is additional pollution which is not needed !

 When measuring the power consumption and the air flow of the 5 units, the real measured specific power consumption was not 6 but 10 kW/m3/min. 

 Explanation is very simple, the units are running at 50% of the capacity, load/unload ! 

 An Oil-injected screw compressor Load/unload can be compared with a Centrifugal blowing off most of its energy at partial load. 

 When the Oil-injected screw is switching from load to unload, the pressure is brought down slowly to avoid foaming of the oil-separator. If running above 50%, in many cases it will not have the time to reach its low pressure, which has still 30% unload power. In reality, the pressure remains quite high resulting in 80% of the power consumption at 50% load.

 As the majority of compressor rooms are operating in partial load, the partial load consumption of the compressed air installation should be the focus !

 How would you solve it ?