To save energy, to use it sensibly or even to re-use it, is a priority today and takes first place when selecting an adsorption dryer. Compressed air dryers consume energy directly and indirectly.
- Direct consumption of heat regenerated dryers in the form of electrical or steam energy as well as power consumption for the blower motor.
- Indirect consumption through pressure loss, leading to higher pressure in the compressor calling for increased power consumption
- Compressed air purge consumption for the regeneration of dryers with heatless or heated regeneration.
In most cases, the purge air consumption of adsorption dryers concerns compressed and already dried compressed air. Closed loop systems regenerated by heat of compression indirectly use energy through the unavoidably increased pressure loss of the system. Expensive operating energy can sensibly be saved through dewpoint or load dependent control systems. However, this is a very complex subject and is described elsewhere (see Section 8). One must accept the principle that energy consumption of a particular system varies widely. It is, therefore, recommended that, in each case, an expert energy system comparison is carried out. The compressed air cost derived from the comparison of the dryer systems, being the result. It is expedient to tailor this system comparison to the consumption requirements. Energy awareness is, however, not only a benefit for the operator but usually justified regarding the capital to be invested. Thus the system comparison preceding the selection of the correct process definitely avoids bad economic decisions.
