As part of its phase II upgrades the Nampa, Idaho Wastewater Division has ordered two MagPrex biological nutrient removal systems, with sequestration, from Centrisys/CNP.
The upgrades will allow Nampa to meet new regulations that mandate Idaho cities to lower phosphorus in wastewater discharge.
In 2010 the City of Nampa began working with technical experts and a committed group, called the Nampa Wastewater Advisory Group, to evaluate options for updating wastewater infrastructure. The group recommended improving Nampa’s wastewater treatment in multiple phases, including reducing phosphorus to an intermediate level.
Phase II includes additional phosphorus reduction to aid in lowering the temperature of nearby Indian Creek and replacing infrastructure at the plant that has reached the end of the lifecycle. To aid in this phase, the city chose the nutrient removal systems offered by Centrisys/CNP, a North American manufacturer of decanter centrifuges and advanced biosolids treatment technologies.
“This will be our second MagPrex installation in Idaho following last year’s design of the system at the Meridian Wastewater Resource Recovery Facility which will be implemented this year,” said Gerhard Forstner, president of CNP and nutrient treatment expert. “Nampa’s consulting engineer, Jacobs Engineering Group Inc., thoroughly evaluated the benefits of our nutrient removal system, and, in partnership with our manufacturer’s representative, Treatment Equipment Company, Centrisys/CNP was awarded the project that will support their phase II initiatives.”
MagPrex’s biological phosphorus removal directs most phosphorus into the solids stream in the form of struvite for dewatering with the cake. By concentrating the phosphorus in the solids stream, Nampa will permanently remove a significant portion of phosphorus from the overall treatment process.
The Nampa Wastewater Division’s new nutrient removal systems will significantly improve treatment efficiency, including:
- Reduced polymer consumption up to 30 percent
- Reduced disposal costs up to 20 percent
- Reduced phosphate recycle loads up to 90 percent
- Reduced maintenance costs up to 50 percent
- No sodium hydroxide required for pH change
“The new system will aid the city in meeting low effluent phosphorus limits, said Forstner. “Rather than using costly and environmentally damaging chemicals, MagPrex will mitigate the high phosphorus levels at the plant with a pioneering process for wastewater treatment plant biosolids optimization and phosphorus recovery.”
Centrisys/CNP now has eight MagPrex installations in the United States, with the Nampa Wastewater Division systems projected to be operational by early 2023.