Author(s): Andrew J. Erickson; John S. Gulliver; Peter T. Weiss; Brian J. Huser
Linked Author(s): John S. Gulliver
Keywords: Sand; Steel wool; Iron; Filtration; Phosphorus; Stormwater management; Adsorption
Abstract: Most treatment practices for urban runoff utilize either settling or filtration to remove compounds associated with particulates (e.g., phosphorus) while dissolved substances are often not captured. Dissolved phosphorus, for example, represents an average of 35-45%of total phosphorus in stormwater but can be more than 95%. Previous research has shown that a combination of sand filtration with 0.3 to 5%by weight steel wool can capture 34%to 81%dissolved phosphorus[1]. In this study, iron filings were tested as an alternative to steel wool for removing dissolved phosphorus for synthetic stormwater. Iron filing sand columns capture on average between 35%and 93%dissolved phosphorus which is significantly more than C 33 sand alone and slightly more than steel wool. A field application of an iron-enhanced sand filter was installed in Maplewood, Minnesota using approximately 5%iron filings by weight with the purpose of removing both total and dissolved phosphorus from stormwater runoff. A model developed from the column studies is used to predict the phosphorus removal in the field application.
Year: 2010