Evaluation of two carbon sources for inducing denitrification: batch and column experiments

Abstract

Artificial recharge improves several water quality parameters. Denitrification is a good example of water treatment process that could be achieved through artificial recharge. To improve the removal of nitrate and other emerging organic contaminants (EOCs) a reactive barrier at the bottom of aninfiltration pond can be added. In the present study, the efficiency in removing nitrate of an artificial recharge system with a compost layer located in the Mediterranean area (Sant Vicenç dels Horts, Catalonia)is evaluated, as well as the feasibility of another carbon source to be used as reactive layer in the artificial recharge system planned in theMaghreb Region. We examined the effectiveness of two different materials, commercial compost and crushed palm tree leaves, in batch and column experiments. The results of batch experiments confirmed that both materials induced denitrification andthe flow-through experiments showed complete nitrate removal. The isotopic fractionation of nitrogen and oxygen of dissolved nitrate was calculated for both experiments in order to provide a tool to evaluate the efficacy of the treatments in future field scale studies.