Journal of Hazardous Materials 175 (2010) 23–32 Contents lists available at ScienceDirect Journal of Hazardous Materials journal homepage: www.elsevier.com/locate/jhazmat Review Assessment of the effectiveness of an industrial unit of mechanical–biological treatment of municipal solid waste R. Bayard ∗ , J. de Araújo Morais, G. Ducom, F. Achour, M. Rouez, R. Gourdon Université de Lyon, INSA-Lyon, Laboratoire de Génie Civil et d’Ingénierie Environnementale LGCIE, 20 avenue Albert Einstein, F-69621 Villeurbanne, France article info Article history: Received 19 May 2009 Received in revised form 18 September 2009 Accepted 12 October 2009 Available online 20 October 2009 Keywords: Mechanical–biological treatment Total carbon balance Landfill Residual municipal solid waste Biogas potential Bio-methane potential abstract An assessment of the French municipal solid waste (MSW) mechanical–biological treatment (MBT) unit of Mende was performed in terms of mass reduction, biogas emissions reduction and biostability of the biologically treated waste. The MBT unit consists of mechanical sorting operations, an aerobic rotating bioreactor, forced-aeration process in open-air tunnels (stabilization), ripening platforms and a sanitary landfill site for waste disposal in separated cells. On the overall plant, results showed a dry matter reduc- tion of 18.9% and an oxidative organic matter reduction of 39.0%. A 46.2% biogas production decrease could also be observed. Concerning the biotreatment steps, high reductions were observed: 88.1% decrease of biogas potential and 57.7% decrease of oxidative organic matter content. Nevertheless, the usually con- sidered stabilization indices (biogas potential, respirometric index) remained higher than recommended by the German or Austrian regulation for landfilling. Mass balance performed on each step of the treat- ment line showed that several stages needed improvement (especially mechanical sorting operations) as several waste fractions containing potentially biodegradable matter were landfilled with very few or no biological treatment. © 2009 Elsevier B.V. All rights reserved. Contents 1. Introduction .......................................................................................................................................... 24 2. Materials and methods ............................................................................................................................... 24 2.1. Description of industrial MBT unit ........................................................................................................... 24 2.2. Waste sampling and characterization ........................................................................................................ 25 2.2.1. Solid waste component materials separation (MODECOM TM procedure) ......................................................... 25 2.2.2. Solid waste chemical characterization ............................................................................................. 25 2.2.3. Solid waste biological stability characterization: biogas potential (BP) and bio-methane potential (BMP) ...................... 25 2.2.4. Solid waste biological stability characterization: respiration index RI 4 ........................................................... 26 2.2.5. Self-heating capacity SHC 10 ........................................................................................................ 26 2.3. Mass balance ................................................................................................................................. 26 3. Results ................................................................................................................................................ 26 3.1. Composition of waste fractions .............................................................................................................. 26 3.1.1. DM, TOC DM and BP distribution in the different categories of materials in the initial MSW (MODECOM TM procedure) ......... 26 3.1.2. DM and BP distributions in waste fractions at the outlet of sieve #1 ............................................................. 27 3.1.3. DM and BP distributions in waste fractions at the outlet of the ARB and sieve #2 ................................................ 28 3.1.4. Biological stability .................................................................................................................. 28 3.2. Mass balance on DM.......................................................................................................................... 29 3.3. Mass balance on VS and TOC DM .............................................................................................................. 29 3.4. Mass balance on OOM, BP and BMP .......................................................................................................... 29 4. Overall discussion .................................................................................................................................... 30 4.1. Efficiency of sieve #1 ......................................................................................................................... 30 4.2. Efficiency of ARB and sieve #2 ............................................................................................................... 30 ∗ Corresponding author. Tel.: +33 4 72 43 87 53; fax: +33 4 72 43 87 17. E-mail address: remy.bayard@insa-lyon.fr (R. Bayard). 0304-3894/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.jhazmat.2009.10.049