AireO2 Triton Aerators Give Wisconsin Treatment Plant a More Efficient Air Supply

With help from a Focus on Energy grant, the Oconto Wastewater Treatment Plant replaced aging aerators with high-efficiency units.

Interested in Energy?

Get Energy articles, news and videos right in your inbox! Sign up now.

Energy + Get Alerts

Editor's Note: This article is part of a profile on the Oconto Wastewater Treatment Plant. Watch for a special feature in the June 2015 issue of Treatment Plant Operator. Not a subscriber? Take care of that right here and now. Click here to have TPO delivered monthly to your mailbox.


The Oconto (Wis.) Wastewater Treatment Plant was running just fine, but that wasn’t good enough for Steve Woodworth, operator-in-charge of water and wastewater.

A few years ago, Woodworth saw an opportunity to improve treatment and save energy by replacing aging aerators with more efficient units paired with oxygen sensors.

The plant’s four aeration basins, which still use original-equipment surface mechanical aerators, now each have two AireO2 Triton process aerator/mixers (Aeration Industries). Mounted to the basin sidewalls, they operate on a feedback loop with inline oxygen sensors.

“The mechanical aerators run 24/7,” says Woodworth. “If we get a load that requires more oxygen, the Triton aerators will kick in, too. Each unit has a blower that delivers air through a tube to a motor-driven impeller, which mixes the air with the water.”

The old aerators had 25 hp motors; each of the new models has a 3 hp motor on the blower and a 10 hp motor on the impeller. The smaller motors cut power costs substantially. A $22,000 grant from Focus on Energy, an energy-saving and renewable energy program sponsored by Wisconsin utilities, helped pay for the $76,000 project.

The Aire-O2 Triton units are designed to foster biological nutrient removal and make it more cost-effective by combining mixing and aeration in a compact unit with separate on/off modes. The impeller/diffuser supports high oxygen transfer and efficient mixing at depths from 6 to 33 feet.

Low-speed operation (900 rpm at 60 Hz) helps extend aerator life, enhances mixing and enables quiet operation. The units do not produce splashing or aerosols, so odors and airborne pathogens are minimized. Float, bridge or wall mountings are available. A design with few wearing parts and simple mechanics limits maintenance.

Before the new aerators were installed with inline oxygen sensing, plant operators had to operate the aerators manually to introduce oxygen when needed. They made decisions based on the appearance of the mixed liquor and on measurements from hand-held dissolved oxygen meters. Now the process is automated, freeing the team for other tasks.



Discussion

Comments on this site are submitted by users and are not endorsed by nor do they reflect the views or opinions of COLE Publishing, Inc. Comments are moderated before being posted.