Integrated Anaerobic–Aerobic Moving Bed Biofilm Reactor and Biochar Adsorption for the Efficient Removal of Organic Matter and Nutrients from Brazilian Landfill Leachate

Landfill leachate is a complex and highly polluted wastewater that poses significant environmental challenges worldwide. This study proposes an innovative approach to addressing this challenge by developing an integrated anaerobic–aerobic moving bed biofilm reactor (MBBR) and biochar adsorption method for the efficient removal of organic matter and nutrients from landfill leachate. The MBBR provides a suitable environment for the growth of microorganisms that can degrade organic matter and nutrients, while biochar adsorption removes any remaining pollutants that are not biodegradable. The performance of this integrated system was evaluated under different operating conditions, such as the hydraulic retention time and the organic loading rate, to optimize its efficiency and sustainability. The results showed that the integrated system achieved high removal efficiencies for chemical oxygen demand (COD), ammonium–nitrogen (NH 4 -N), and total phosphorus (TP), with maximum removal rates of 98.5% (77% after the anaerobic–aerobic MBBR and 85.4% after biochar adsorption), 91.2% (87% after the anaerobic–aerobic MBBR and 95.9% after biochar adsorption), and 99.9% (92% after the anaerobic–aerobic MBBR and 91.7% after biochar adsorption), respectively. The proposed method offers a promising solution for the treatment of landfill leachate, which is a critical environmental issue worldwide. This study also highlights the importance of developing more effective and sustainable methods for treating landfill leachate, which can have significant impacts on public health and the environment.