Kruger Inc., a Veolia Water Solutions & Technologies company, received the purchase order from Penta Corp. to furnish the AnoxKaldnes IFAS process for the expansion and upgrade of the Hooksett, N.H., Wastewater Treatment Plant. Hooksett’s facility will be one of the first wastewater treatment plants in New Hampshire with biological nitrogen removal and it will also be the first plant in the United States to use the high-surface-area Biofilm Chip M IFAS media with 1,200 m2/m3 of specific surface area.
By using the Biofilm Chip M media, Graves Engineering of Worcester, Mass., was able to design the upgrade of the wastewater treatment plant without the construction of additional aeration tanks on the highly constrained site, which saved Hooksett Sewer Commission more than $1.0 million. When the plant goes online in the spring of 2011, the treatment capacity will be increased from 1.1 million gal per day (mgd) to 2.2 mgd. Target effluent concentrations are 15 mg/L BOD, 15 mg/L total suspended solids and 1 mg/L of ammonia. Nitrogen will be removed in anoxic zones upstream of the IFAS aeration tanks by returning nitrified mixed liquor to the anoxic zones, and anaerobic zones are being constructed for biological phosphorus removal.
The plant expansion is being funded in part by the American Recovery and Reinvestment Act. While most of the media is produced in the United States, this specific type is not. Therefore, to comply with the Buy American Requirements, Graves Engineering, in conjunction with Kruger Inc., obtained a waiver for the foreign-made Biofilm Chip media. This was the only media that could meet the design objective of expanding the plant without the need to construct additional aeration tanks.
In addition to the Biofilm Chip M media, Kruger is also supplying the medium bubble aeration grids for the IFAS zones, and media retention sieves.
Source: Kruger
