Evaluation of Leachate Recirculation as a Stabilisation Strategy for Landfills in Developing Countries

This study evaluated leachate recirculation (LR) as a stabilisation strategy for landfills using bioreactor experiments with excavated waste from tropical landfill in Colombia. The experimental evaluation was performed two 115 L bioreactors, one simulating the operation of LR, Br2, where produced recirculated at rate 0.8 d−1, and control system without Br1. Both systems reached indicator values on dry matter (DM) basis volatile solids VS (<25% DM) biochemical methane potential BMP (≤10 mL CH4 g−1 DM). Likewise, towards end experiment, generated Br2 BOD5 (<100 mg L−1) BOD (biological oxygen demand)/COD (chemical demand) ratio (<0.1). Although criterion COD not met any (<200 L−1), LR helped to release 19% more oxidisable organic than Br1, indicating reduction contaminating case uncontrolled discharges environment. Regarding biogas production, generation intense its cumulative production 34.5% higher Br1; thus, achieved emission rates, (<1.0 m−2 h−1) sooner showing an accelerating effect degradation. A carbon mass balance indicated that degradation, terms initial total mineralisation C gas discharge via CH4, greater Br2. These results demonstrate accelerate but also reduce greenhouse emissions final disposal sites is captured utilised energy production; key aspect when improving sustainability operations developing countries.