One of the most underrated items of plant in an air system, a correctly sized air receiver can significantly lower energy costs by providing compressed air storage and a buffer between the compressor and reticulation system, explains Mark Ferguson, National Sales & Marketing Manager at Southern Cross Compressors Australia Pty Ltd .
A correctly sized vessel has the effect of limiting the load/unload cycles (or stop/start cycles) of the compressor, reducing excessive wear and tear on the control system and drive motor. However, it also has the affect of extending the off load cycle time for partly loaded compressors, which can result in significant energy savings.
The ‘off load’ time is a function of vessel volume, pressure settings and plant demand. Cycling compressors vent their internal pressure when ‘off load’ to reduce absorbed power. If the off load time is too short, the compressor never really fully unloads, resulting in significantly higher energy usage.
Air receivers offer the added benefit of separating liquid condensate entrained in the compressed air. By reducing the vertical particle velocity to below 0.6m/s, the droplet will fall out under gravity and is easily drained away. This will reduce the moisture load on corresponding filters and dryer, improving their life and efficiency.
An air receiver won’t provide more air for the plant than what the compressor/s can deliver. In some circumstances however, an engineered air receiver can accommodate a high demand over a short time frame without the need to invest in a larger compressor. For instance, in a tyre fitting situation where air is used in short bursts, a larger air receiver is often the right solution resulting in significantly lower investment and running costs. The energy saving benefit of extra storage capacity alone outweighs the additional cost of this component.
All compressed air systems can benefit by having the right size air receiver regardless of the size and type.