USING THE LEACHING TEST TO STUDY THE EFFECT OF DIFFERENT WASTE MANAGEMENT SCHEMES ON THE STABILITY OF MSW IN SEMI-INDUSTRIAL SCALE PILOTS: APPLICATION TO BIOREACTOR AND BIOMECHANICAL PRETREATEMENT

摘要

Municipal Solid Waste (MSW) production is estimated at 391kg/year/person in France (ADEME 2010). An important percentage of this waste goes to landfills which remain the most commonly used mode of waste treatment in this country. Although leachate and biogas can be considered as relevant indicators of stabilization of the waste, they are not sufficient to determine the stability of the system. With time, leachate global parameters seem to be stabilized while the very slowly biodegradable fractions of the waste continue to evolve (Berthe et al., 2008). Leaching tests are laboratory tests used to determine the quality and quantity of leached pollution, thus they can be also applied to stabilized waste. The present work aims at using a completed and adapted leaching test developed by Parodi et al. (2010) to evaluate the stability of excavated waste of four experimental semi-industrial scale pilots after 5 years of landfilling (ELIA program). This Leaching Test (LT) assesses the biodegradability of the waste through analyses on liquid, solid and gaseous phases. In this study, the LT test is used to determine the impact of the different modalities of waste treatment: control, bioreactor and two aerobic pretreatments. Measurements of global parameters and characterization of the organic matter in the liquid phase were used to evaluate the state of degradation of the waste in each pilot. The results have shown that at the leachate recirculation rate defined in the study, an important proportion of the organic molecules remains trapped within the solid waste matrix.