Energy-efficient oil-injected industrial compressors
August 29th 2008 The new Atlas Copco GA+ 90-160kW range offers users a premium performance package with free air delivery and energy efficiency. These are claimed to be the first oil-injected compressors worldwide to integrate a water separator into the compressed air cooling system, thereby reducing internal pressure drops by 50% and contributing 2% to overall energy efficiency. What’s more, these are Atlas Copco’s first air compressors to offer VSD-controlled cooling fans.
The GA+ VSD version alone is said to have broken eight performance records within the compressed air industry in terms of overall energy requirements, energy consumption of individual elements and the lifetime of replacement parts.
The Specific Energy Requirement (SER) of the GA+ range is the best-in-class – 350Joule/litre according to ISO 1217 edition 3 annex C (1996), thereby using up to 11% less electrical power than the previous GA models. Added to this, the new GA 160 VSD model offers the widest free air delivery (FAD) turndown range – from 100% to 17%. That is at least 18% greater than that of any comparable models.
Operating at pressures from 3.5 to 14bar(e), these machine are capable of the most energy-efficient performance even in ambient temperatures of up to 55°C – and at a maximum noise level of 71dBA, in comparison to the previous benchmark of 75dBA. They also offer a doubled lifetime for both the oil filter and the air inlet filter.
A major contribution to superior energy efficient performance is made by the compression elements, based on Atlas Copco’s patented asymmetric rotor profiles, designed for a 5-6% drop in energy requirements and a drastic reduction of volumetric losses.
Thermodynamic losses are also minimised through optimisation of oil-injection, flow and temperature, so that the compression process is kept as cool as possible.
Other features designed to reduce energy consumption include high efficiency motors and no-loss drains, plus the installation of radial fans with VSD regulation, capable of reducing energy requirements by up to 59%. All components have been optimally integrated to reduce floor space and simplify connections.
Air quality is assured by two key elements: a highly efficient oil removal system to give minimum residual oil content in the outlet air, and state-of-the-art refrigerant dryers. The dryers are available in both integrated and stand-alone versions, which, together with an air filter, ensure a continuous supply of clean dry air to extend the life of downstream equipment, enhance system reliability and avoid costly downtime and production delays. With the integration of its patented Saver Cycle Control, Atlas Copco has achieved further energy savings for its refrigerant dryers of up to 30% in normal load conditions. More articles from Atlas Copco Compressors Ltd: | 
