Press Release

Application of CoMagTMballasted magnetite technology to achieve total phosphorus consents of <0.1 mg/l at the Billerica WwTP in Massachusetts

Jeff Kalmes will present the paper, “Phosphate Removal—a summary of the 5 years operation of the CoMag phosphate removal plant at Billerica, Massachusetts, USA” at the European Waste Water Management Conference, October 12-13 in Manchester, England. He is the Wastewater Treatment Plant Supervisor at the Billerica Wastewater Treatment Plant, a 21.25 ML/d (5.5 MGD) capacity facility that is located 20 miles northwest of the city of Boston.

The paper details Billerica’s search for a Phosphorus removal technology to meet stringent new limits set by its National Pollutant Discharge Elimination System (NPDES) permit. Added to this, a warning had already been given that Billerica’s wastewater treatment plant would be expected to achieve a summer Total Phosphorus of 0.1mg/l in the near future. The plant had been using a two-point chemical addition phosphorus removal system, but it was not adequate to remove total phosphorus and aluminum to the concentrations soon required at the facility. A new tertiary phosphorus removal system would be required.

The engineering consultants for Billerica, Woodard and Curran, were commissioned to undertake an evaluation of the most suitable available technologies required to achieve these new onerous Phosphorus limits. The technologies considered were enhanced biological phosphorus removal, effluent cloth filters, and a process that had just been installed at a similar waste plant called CoMag™.

“Compared to the other Phosphorus removal technologies, the CoMag process appeared to be the most reliable to achieve the new more stringent Total Phosphorus levels that would be required,” says Kalmes.

For the reliability and cost, it was decided to go with the CoMag process provided the reliability was proven by a pilot plant trial.

“The Town of Billerica was interested in trying a solution that was new and cutting edge. Based on our experience, we believed that the CoMag process would consistently meet these stringent limits,” adds Tom Hazlett, a Vice President and Project Manager at Woodard & Curran.

However, one of the challenges of installing a new process that had to be reconciled was the lack of full-scale installation data and a full understanding of the requirements of operating such a new process.

A pilot plant was brought to the Billerica WWTP and operated under various regimes for several months to verify the performance expected. The treatment plant staff collected and tested samples alongside engineers from Cambridge Water Technology, the developers of the CoMag technology. In addition to this, a third sample was collected and sent out to a private laboratory. This was done as a final check on all the work being conducted. After several months of sampling and testing, the results confirmed that CoMag was the optimal treatment process.

The innovative CoMag technology enhances conventional coagulation by utilising Magnetite as a ballast, which increases the weight of the flocs, and this results in significantly improved effluent quality, in particular TSS and Phosphate. This paper will discuss why Phosphorus removal technology was required at Billerica and the operational performance of the CoMag process. It will also examine the challenges of introducing, what was then, an untried technology to an established wastewatertreatment works and how such challenges were solved.

The $12.3 million project is one of the first of its kind, and it provides highly treated wastewater to assure that the Town of Billerica is doing their part to keep clean its receiving water, the Concord River.

Jeff Kalmes has more than 28 years of experience in wastewater treatment. He is the recipient of the 2011 Water Environment Federation National Public Educator of the Yearaward and the New England Water Environment Association’s 2008 Public Educator award.