De Nora celebrates 10 years of operation in Chesapeake Bay

De Nora TETRA Denite filters set industry standard for biological nutrient removal

A decade after installation, De Nora reported uninterrupted operation and successful biological nutrient removal at the Arlington County Water Pollution Control Bureau (WPCB). Since 2010, De Nora TETRA Denite filter technology has effectively lowered nitrate, phosphorus and total suspended solids (TSS) from wastewater discharged into the Four Mile Run region of the Potomac River, improving water quality conditions of the Chesapeake Bay and surrounding environment.

The project was included in a US$568 million upgrade to the 75-year-old WPCB, which, at the time, had not been renovated since the early 1990s. A total of 17 De Nora TETRA Denite filters were installed to meet anticipated nutrient regulations, including a total of nitrate limit of approximately 3mg/L with a concurrent low total phosphorous limit of 0.18mg/L. The plant was one of the first major effluent denitrification facilities to achieve these benchmarks consistently, and has received several accolades in response.

Kacey King-McRae, operations specialist at WPCB, said: “De Nora filters were successful at bringing our total nitrogen concentration down to meet laws and regulations pertaining to nutrient permit loadings. The De Nora system is fully automated, requiring very little operator interaction. It’s the future of wastewater treatment.” For more than 50 years, De Nora TETRA DeepBed filtration technologies with Snap T block underdrain filters have been polishing municipal wastewater effluent to reuse standard and regulatory discharge limits with minimal intervention. For potable water applications, De Nora ozone and biological filtration technologies are combined to provide advanced filtration, oxidizing micropollutants to treat contaminants of emerging concern while mitigating disinfection byproduct formation.