Atlas Copco Compressors showcased its range of low pressure blowers for the wastewater industry at the 2014 Water Environment Federation Technical Exhibition and Conference (Weftec) at the New Orleans Morial Convention Centre, Weftec is the wastewater industry’s flagship tradeshow.

Products on display included the ZB range of centrifugal air blowers, the ZM range of multistage centrifugal blowers and the ZS range of oil-free screw blowers, which is celebrating its fifth year of production. With the launch of the ZS range in 2009, and through innovations in blower technology and investments in Houston Service Industries (HSi) and their range of energy efficient high-speed turbo blowers, Atlas Copco carries a comprehensive range of blower technologies for the wastewater industry.

“Not only is the ZS range up to 40 per cent more energy efficient than a tri-lobe blower, but it also complies with ISO 8573-1 Class Zero certification for 100 per cent oil-free air, completely eliminating the risk of oil contamination,” said Erik Arfalk, vice president communications and branding, Atlas Copco Compressors. “Our commitment to sustainable productivity is reflected in the ZS range and the technologies we develop to reduce energy consumption by increasing efficiency.”

The efficiency of the ZS range is attributed to its use of screw technology versus conventional lobe technology. The screw compression element has a fixed, built-in pressure ratio and has no mechanical forces that cause unbalance, allowing high shaft speeds and large flow rates with small exterior dimensions. The internal air flow path is also optimised to reduce pressure drops and air turbulence and a direct drive integrated gearbox reduces transmission losses. The combination of these elements plus the integrated variable speed drive (VSD) results in a machine that uses 30 per cent less energy than the previous lobe type blowers.

In the wastewater treatment process, millions of bacteria feed on organic waste, breaking it down into carbon dioxide, nitrogen and water. Because these bacteria require oxygen as part of this process, large quantities of air are blown into aeration tanks. Digester gas, a byproduct of the process, can also be upgraded and compressed to generate electricity. Because air and gas blowers typically represent up to 70 per cent of the total electricity costs at water treatment facilities, many facilities that incorporate the latest technologies are able to reduce these costs by an average of 30 per cent.

In addition to wastewater treatment, other industries with blower applications that can benefit from the latest energy saving technologies include pneumatic conveying, power generation, food and beverage, pharmaceuticals, chemicals, pulp and paper, textiles, cement and general manufacturing.