Environmental impacts of landfill bioreactorcells in comparison to former landfill techniques

Former and present landfill techniques at the Filborna plant in Helsingborg, South Sweden are compared with respect to impacts on the environment. This includes the potential for nutrient recovery and heavy metal immobilisation in the waste residue. The results show that optimised landfill bioreactor-cells have a higher turn-over rate for organic matter compared to the former landfills, whereas the retention capacity for heavy metals in both systems was surprisingly high. Full scale leachate data, as well as a laboratory leaching experiments confirmed the role of bioreactor cells as anaerobic filters enabling a separation of nutrients from a mixed waste, while the toxic metals are retained. The conclusion of this article is that by simple measures, the biological processes can be optimised, resulting in higher turn-over rates for organic matter and thus accelerated waste stabilisation.