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Updated: May 27, 2026
08:05
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Nitrate removal using different carbon substrates in a laboratory model.
Seyyed Ebrahim Hashemi1, Manouchehr Heidarpour, Behrouz Mostafazadeh-Fard
1Water Engineering Department, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111.
Summary
Date palm leaf biofilters effectively removed nitrate from agricultural runoff, outperforming wood, barley straw, and rice husks. Optimal performance was achieved with higher nitrate concentrations and slower water flow, meeting drinking water standards.
Area of Science:
- Environmental Science
- Water Quality Management
- Agricultural Engineering
Background:
- Agricultural fields are significant sources of nitrate leaching into water bodies.
- Tile drains facilitate direct nitrate transfer to surface waters.
- Bioreactor filters can remove nitrate via denitrification but require external carbon sources.
Purpose of the Study:
- To evaluate four organic carbon sources for enhancing denitrification in bioreactor filters.
- To assess the impact of water velocity and influent nitrate concentration on nitrate removal efficiency.
- To determine the most effective organic material for nitrate reduction in agricultural drainage water.
Main Methods:
- Four organic carbon sources (wood, barley straw, rice husks, date palm leaf) were tested in bioreactor filters.
- Denitrification rates and cumulative nitrate removal were measured.
- The influence of varying water velocities and influent nitrate concentrations was investigated.
Main Results:
- Date palm leaf treatments showed the highest cumulative nitrate removal, while wood showed the lowest.
- Nitrate removal efficiency increased with higher influent nitrate concentrations and decreased water velocity.
- All tested treatments successfully reduced effluent nitrate concentrations below the 45 mg L(-1) USEPA maximum contaminant level.
Conclusions:
- Date palm leaf is a highly effective substrate for nitrate removal in agricultural drainage bioreactors.
- Optimizing water flow and influent nitrate levels enhances bioreactor performance.
- Biofilter technology using organic materials offers a viable solution for mitigating nitrate pollution from agricultural sources.
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