Development of electrodialysis with bipolar membrane for the treatment of concentrated nitrate effluents

The reprocessing of nuclear combustibles results in the generation of concentrated liquid wastes, An important effluent produced is ammonium nitrate solution. The treatment of this solution by electrodialysis using bipolar membranes is complicated by the leakage of ammonia through the membranes. The treatment involves a two-step process: ammonia stripping after neutralization of NH4NO3 by NaOH (or KOH) followed by a regeneration of NaOH (or KOH) by electrodialysis with a bipolar membrane, which also produces HNO3. This process allows the regeneration of nitric acid and base which can be recycled in the industrial process and is an example of a clean technology with zero effluent production (zero nitrate rejection).