Hach RTC105Wastewater plants are often permitted based on the amount of nitrogen and ammonia they are allowed to discharge. But in many cases, the tendency is to over-aerate so as to ensure always being within compliance, says Bob Dabkowski, wastewater specialist with Hach Co., Loveland, Colo.

Hach is a supplier of analytical instruments and reagents for water testing and water quality analysis. The company says it has developed a packaged solution that brings energy and other savings to those lacking resources for the kind of custom engineering needed to establish consistent control of nitrogen levels in the effluent. The new RTC105 Nitrification/DeNitrification System provides real-time control of nitrification and denitrification in oxidation ditches and sequencing batch reactors.

While some facilities have realized savings by throttling aeration based on dissolved oxygen levels, Dabkowski says, the Hach solution can compound those savings by adjusting aeration based on real-time ammonia and nitrate concentrations.

“What makes the RTC105 great is it allows existing oxidation ditches or sequencing batch reactors the ability to produce a better effluent with less energy, potentially eliminating the need to build extra tanks or other costly construction projects.”  Dabkowski says.

Hach says that within an hour of installation, the RTC105 can be fully operational and controlling the aeration process.  The system has been commercially available in Europe for about four years now, says Dabkowski, and delivered 10% to 30% in energy savings, in addition to savings already realized through regular dissolved oxygen control, as well as better control of nitrate and ammonia. “We’re seeing early adopters come out here in North America,” Dabkowski concludes, “based on better control and an off-the-shelf solution supported by Hach.”