Efficiency of a pilot system using wetlands in the post-treatment of the leachate generated in the Curitiba Landfill, Curitiba, Paraná, Brazil

ABSTRACT In the Curitiba Landfill the post-treatment of the leachate occurs in natural wetlands. In order to evaluate the role of macrophytes in this post-treatment, it was developed a pilot system. Thus, the objective of this study was to evaluate the effectiveness of the pilot system in the post-treatment of the leachate in this landfill. The system was built with two water tanks: the macrophyte Echinochloa polystachya was placed in the first one; and the Eichhornia crassipes was placed in the second one. The system operated in batch in a seven-day cycle. For monitoring the system, samples were collected, and analyses of the leachate, the substrate, and the macrophytes were performed. The efficiency of the system in the post-treatment of the leachate was 72% for biochemical oxygen demand, 30% for chemical oxygen demand, 76% for total phosphorus and inorganic phosphorus, 38% for nitrate, 33% for nitrite, 58% for ammoniacal nitrogen, 44% for organic nitrogen, and 13% for zinc.