Denitrification of a nitrate-rich synthetic wastewater using various wood-based media materials.

This laboratory study examined the use of various wood materials as a carbon source in horizontal flow filters to denitrify nitrate-nitrogen (NO3-N) from a synthetic wastewater. The filter materials were: sawdust (Pinus radiata), sawdust and soil, sawdust and sand, and medium-chip wood chippings and sand. Two influent concentrations of NO3-N, 200 mg L(-1) and 60 mg L(-1), loaded at 2.9 to 19.4 mg NO3-N kg(-1) mixture, were used. The horizontal flow filter with a wood chippings/sand mixture and an influent NO3-N concentration of 60 mg L(-1), which operated over a study duration of 166 days, performed best, yielding a 97% reduction in NO3-N at steady-state conditions.