BIOLOGICAL DENITRIFICATION OF NITRATE CONTAMINATED GROUNDWATER WITH MOVING BED BIOFILM REACTOR

Abstract

In recent years, the massive and uncontrolled use of fertilizer in agriculture has increased the level of nitrate in groundwater up to make this strategic and valuable source of water useless or not convenient for drinking water purpose. Several processes have been tested to remove nitrate from groundwater and although efficient, they require high capital as well as management costs. Biological processes represent a valid and low cost alternative to remove nitrate from water. This paper, actually, presents the preliminary and encouraging results of the startup and operating of a bench scale 1.8L Moving Bed Biofilm Reactor (MBBR) to remove biologically nitrate. Kaldnes K1were used as biofilm carrier and the reactor was fed with synthetic water simulating a typical groundwater with different concentrations of nitrate, i.e. NO3 --N ranging from 30 to 60 mg/L. Acetate was added as carbon source