Analysis of MSW full-scale facilities based on anaerobic digestion and/or composting using respiration indices as performance indicators

Abstract

The Landfill Directive (1999/31/EC) forces European States to reduce the amount of biodegradable municipal waste landfilled to 35% of 1995 levels. Mechanical-Biological Treatment (MBT) plants are the main alternative to waste incineration and landfilling. In this work, the waste treatment efficiency of six full-scale MBT facilities has been analysed using respiration indices (Dynamic Respiration Index and Cumulative Oxygen Consumption) to monitor plant performance. MBTs relying on anaerobic digestion plus composting achieved a high grade of stability on final compost (0.24±0.09mgO₂g^-1DMh^-1 and 20±9mgO₂g^-1DM for dynamic respiration and cumulative consumption, respectively). On the contrary, MBTs relying only on composting showed a poor performance (1.3±0.2mgO₂g^-1DMh^-1 and 104±18mgO₂g^-1DM for dynamic respiration and cumulative consumption, respectively). These results highlight the usefulness of respirometric balances to assess the performance of MBT full-scale plants.

Keywords: Anaerobic digestion; Composting; Cumulative Respiration Index; Dynamic Respiration Index; MBT.