freefallingbody
Electrical
- Aug 18, 2003
- 55
Dear all,
While analysing the enegry efficiency performance of air compressor, I found difficult to understand the following:
When air is compressed, say from atmosphere to 8 bar(g), the air temperature rises. After the first stage of compression, some heat is removed in the intercooler before the air proceeds to the second stage. Some heat is again removed in the aftercooler after the second stage. The energy balance in this case looks like:
energy input to compressor = heat removed from the air + energy stored in compressed air in the receiver.
So far so good.
Literatures on compressed air systems published by US Dept. of Energy says that the compressed air is a very expensive utility BECAUSE A LOT OF HEAT IS REMOVED DURING AND AFTER COMPRESSION. ( 85% input energy is removed as heat)
Does this mean that efficiency is poor because I am removing lot of heat? What if I cool the compressed air to ambient temperature in the aftercooler? very low efficiency?
Or I am I just confusing myself unnecessarily?
While analysing the enegry efficiency performance of air compressor, I found difficult to understand the following:
When air is compressed, say from atmosphere to 8 bar(g), the air temperature rises. After the first stage of compression, some heat is removed in the intercooler before the air proceeds to the second stage. Some heat is again removed in the aftercooler after the second stage. The energy balance in this case looks like:
energy input to compressor = heat removed from the air + energy stored in compressed air in the receiver.
So far so good.
Literatures on compressed air systems published by US Dept. of Energy says that the compressed air is a very expensive utility BECAUSE A LOT OF HEAT IS REMOVED DURING AND AFTER COMPRESSION. ( 85% input energy is removed as heat)
Does this mean that efficiency is poor because I am removing lot of heat? What if I cool the compressed air to ambient temperature in the aftercooler? very low efficiency?
Or I am I just confusing myself unnecessarily?