Enhanced purification of landfill wastewater
Leaching of potentially toxic liquids into soil and groundwater is particularly problematic, as is the relevant treatment process. Leachate wastewater profiles vary tremendously not only among landfills but even within an individual landfill over time. Varying properties, loads and local or regional effluent discharge regulations combined with inefficient biological wastewater treatments (microbes cannot survive to do their work in such highly contaminated environments) reinforce the need to develop new, effective and inexpensive technologies for treatment of landfill wastewater. European researchers initiated the 'Modular purification system for heavily polluted leachate' (PURILEACH) project to develop a site-adaptive approach using 'smart' feedback to optimally select treatment regimes depending on specific wastewater characteristics. The prototype consisted of five treatment modules and an operational system of hardware and software enabling automatic control of treatment parameters depending on wastewater composition and quantity. Its installation in numerous landfills in the United Kingdom and continental Europe provided valuable information leading to design and process optimisation. The final system achieved all project specifications at a significant cost reduction compared to conventional methods. In addition, researchers concluded that increasing tank size would lead to further cost savings on an industrial scale. PURILEACH project outcomes have important implications for the safety of Europe’s landfills and for the quality of local soil and groundwater. Given that landfills are the main way Europe disposes of its municipal and hazardous waste, ensuring their safety is critical to the well-being of Europe’s citizens and the environment.
