Can We Recycle Nitrate Instead of Wasting It?.

It is nearly impossible to produce annual row crops like corn without nitrate leakage, which has well-known environmental consequences.  To this point, mitigation efforts have largely focused on denitrification – encouraging microbial reduction of NO₃ to N₂. This seems wasteful since initial production of nitrogen fertilizer from N₂ is energy intensive and generates substantial greenhouse gas emissions.  Electrodialysis may offer a means to extract nitrate from drainage water and concentrate it for re-use in fertigation, using renewable energy sources - solar and wind power.  We have conducted greenhouse and small field experiments to verify proof of concept and to generate parameters needed to model field-scale application and to develop cost estimates.  There are a number of challenges to overcome, but initial results are promising.