Wastewater, Not Waste Energy

Recently, officials in the Town of Huntington, New York – home to more than 200,000 residents and located on the north shore of Long Island – identified a need to upgrade portions of their wastewater treatment facility.

Wastewater treatment facilities use low pressure blowers as a critical part of the treatment process, fostering the waste breakdown progression between primary and secondary cycles. Wastewater treatment includes millions of bacteria that feed on organic waste to break it down to carbon dioxide, nitrogen and water. Because these essential bacteria need oxygen, large quantities of air are blown into aeration tanks.

As a critical function that is in operation 24 hours a day, seven days a week, blowers typically represent up to 70 percent of the total electricity costs for municipal and industrial wastewater treatment plants – about $3 billion annually. By reducing the energy use of its aeration blower systems, Huntington would decrease energy costs while operating more efficiently and in an environmentally friendly manner.

Like most capital projects in nearly every city or town, regardless of size or scope, Huntington officials launched a competitive bid process. As part of the process, town officials conducted a head-to-head test between the different manufacturers they were considering. This, they concluded, would ultimately show how to make the wisest investment.

Throughout the test each manufacturer’s machine was run simultaneously to ensure conformity with stated requirements and to enable the town’s consulting engineer to record each machine’s energy-efficiency level.

In the end, Huntington selected three Atlas Copco ZS75-k-900 low pressure screw blowers for the town’s wastewater treatment facility. They chose Atlas Copco low pressure screw blowers because their tests showed our machines provided 30 percent greater efficiency than the competition and reliable delivery of 100 percent oil-free air.

An additional benefit of our screw blower technology, beyond energy efficiency and the resulting savings, is a screw blower is much quieter than other blower technologies. Screw blowers operate at about 75 dBa versus as much as 90 dBa for rotary lobe blowers. That variance is roughly the difference between the buzz of a busy restaurant and the noise generated by a running lawn mower. Additionally, Occupational Safety and Health Administration mandates that employees subjected to occupational noise levels that reach or exceed 85 dBa for exposure periods of eight hours or more be administered a continual hearing conservation program. Employee exposure to noise levels less than 85 dBa do not require any additional safeguards or precautions.

If you use blowers in your wastewater treatment or manufacturing facility, consider the benefits of upgrading to screw blowers – the capital costs can likely be paid back in energy savings in less time than you think.