Features Drainage Management Systems
New system could remove both nitrate and phosphorus from ag fields

In a recent study, Laura Christianson, assistant professor of water quality in the Department of Crop Sciences at the University of Illinois, and several colleagues looked at whether they could remove phosphorus in woodchip bioreactors by adding a special “P-filter” designed to trap the fertilizer-derived pollutant. The team tested two types of industrial waste products in the P-filters: acid mine drainage treatment residual (MDR) and steel slag. 

Nitrate removal was consistent, regardless of P-filter type and whether the P-filter was upstream or downstream of the bioreactor. But MDR was far superior as a phosphorus filter. “It removed 80 to 90 percent of the phosphorus at our medium flow rate,” Christianson says. | READ MORE