Mechanical-Biological Treatment : A must for future waste upgrading technologies. Arthur Wellinger Task Leader Task 37. What is MBT?

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1 Mechanical-Biological Treatment : A must for future waste upgrading technologies Arthur Wellinger Task Leader Task 37 What is MBT? Mechanical-Biological-Treatment (MBT) processes household waste by mechanically separating some parts of the waste and biologically treating others MBT is a very flexible waste management tool but seldom a stand-alone technology MBT is a well established waste upgrading technology in most parts of Europe

2 The two basic functions M(echanical ) refers to sorting, size reduction, separation and sieving technologies achieving separation of potentially useful products and streams for biological s B(iological ) refers to anaerobic and/or aerobic or processes which convert the organic fraction into a compost-like material and biogas What are the goals of MBT? Help to meet landfill diversion targets Boost recycling performance Reduce the need for incineration Improve product quality Avoid source separation Minimise waste processing cost Reduce implementation time (less public concern) Yes, but not everything at the same time

3 What type of waste is MBT suited? Entire MSW: Black bag Key role plays the mechanical part. It has to be robust and flexible Hand sorting has often to be included M is to prepare input to B rather than recycling Source separated residual waste: Grey bag Lower quantities of waste for M Less sophisticated M (shredding, sorting, etc.) The most widespread options for MBT Make energy & landfill MSW Mechanical AD Aerobic Dry recyclables RDF I Landfill Produce & soil improver MSW Mechanical AD Aerobic Dry recyclables Rejects Compost

4 The lowest cost option for MBT MSW Mechanical AD Aerobic Landfill Dry recyclables Landfill Landfill Partial MBT with landfilling The ecologically best solution Household Waste Source Separation Grey Waste Mechanical Separation RDF I OFMSW Digestion Thermal Digestion Post- Surface Application Fertilizer Compost RDF II Dedicated Combustion

5 Percentage of Population hooked to an MBT Martin Steiner, 2005 Countries with the highest share of MBT Installed capacity of operational facilities by location Italy Germany Spain 6'500 5'700 Australia Netherland Austria USA France Belgium Canada UK Poland Turkey Japan Portugal Israel Input Capacity (in 1'000 Tonnes per annum) Total installed capacitiy approx. 20m tons

6 Commercially available MBT systems In total there are more than 50 technology providers claiming experience with MBT. Only 26 processes have full-scale operating plants: Germany: Biodegma BTA/MAT Haase Hese Horstmann ISKA Linde Nehlsen RosRoca Sutco UK: CIVIC New Earth Wastec Austria: Komptech VKW Italy: SCT EcoDeco NL: Grontmij CH: Kompogas B: OWS SF: Citec Rumen F: Valorga USA: Bedminster Israel: ArrowBio Canada: Wright Example: Valorga MBT with AD: Dry digestion

7 Example: Valorga MBT with AD: Dry digestion Example: Valorga MBT with AD: Dry digestion

8 MBT with AD: Wet digestion (1) Example: Omrin = waste storage 2 = separation unit 3 = washing unit 4 = digestion unit 5 = power plant MBT with AD: Wet digestion (2) Example: Omrin Separation unit Washing unit Digestion unit Water Paper/ plastics 16% RDF 40% suspension (9,4%) Inert 6% 6% 220,000 tonnes (OFMSW) (41%) Organics 36% Digestate 16% 100% Ferro/ non-ferro 3% Sand 5% Residue 3% Effluent 14%

9 MBT with AD: Wet digestion (3) Example: Omrin MBT with AD: Percolation (1) Example: UR-3R Sydney Plant thruput: tpy Landifill diversion: 80% Income from: gate fee electricity Recycled prod OGM CO 2 -equivalent

10 MBT with AD: Percolation (2) Example: UR-3R Sydney MBT with AD: Percolation (3) Example: UR-3R Sydney Percolation Organic fraction

11 MBT with AD: Percolation (4) Example: UR-3R Sydney Digestion MBT with AD: Percolation (5) Example: UR-3R Sydney Composting & Refining

12 Can we afford MBT? Type calculations based on the percolation system: 1. Mass balance Digester 8.5% Household waste Mech. Percolator Composting Mech. Fe 3% > 120mm 12% Sand Degradation 3% 1% Water 11.3% Water 10% > 60mm 8% Landfill 43% MBT before an existing incinerator tpy small business waste tpy household waste 103 per t Household waste Small business waste tpy Digester 8.5% Household waste Mech. Fe 3% > 120mm 12% Percolator tpy Sand Degradation 3% 1% Water 11.3% tpy Incineration

13 MBT & incineration: Household waste grey bag tpy household waste 79 per t Household waste tpy Digester 8.5% Household waste Mech. Fe 3% > 120mm 12% Percolator tpy Sand Degradation 3% 1% Water 11.3% tpy Incineration tpy 150 /t tpy 40 /t MBT, incineration & landfill 79 per ton tpy tpy Digester 8.5% Landfill 43% Household waste Mech. Percolator Composting Mech. Fe 3% > 120mm 12% Sand Degradation 3% 1% Water 11.3% Water 10% > 60mm 8% Incineration tpy tpy

14 Conclusions MBT is a low cost and reliable option within the processes of waste upgrading It is particularly well suited in developed countries where landfill capacities are still available and emissions are to be reduced It is a low cost option to allow more waste to be treated in an existing incineration plant It is an excellent and cost efficient tool in developing countries where most of the (organic rich) waste is still dumped It is an excellent means to produce soil improvers for arid areas