Incineration & landfilling Håkan Jönsson Professor Hakan.Jonsson@et.slu.se Swedish University of Agricultural Sciences Håkan Jönsson Department of Energy and Technology

Department of Energy and Technology Waste incineration Renewable fuel: 80-90% of Swedish household waste is renewable (incineration tax assumed 87.4%) Heating value: 2,5-3,2-4 kWh/kg, 9-11,5-14 MJ/kg Heterogeneous ”dirty” fuel Extensive flue gas cleaning necessary Large plants Storage needed but difficult Even production over the year Difficult when biowaste is included Håkan Jönsson Department of Energy and Technology

Department of Energy and Technology Waste incineration 2008 29 incineration plants for household waste, 4.6 Mton/yr, of which 2.3 Mton/yr household waste Sizes; > 200 000/yr 7 plants (Sthlm, Gbg, Lin, Mö, Stje, Svall, Ua), 100 000 - 200 000/yr 4 plants and <100 000/yr 18 plants Energy recovery 12.2 TWh heat (29% of district heating) & 1.5 TWh electricity (1% of electricity use) Mass decreases by 75%, volume by 90%. Residues: slag 20%, fly ash 3-5% (hazardous waste) Initially introduced for mass and volume reduction Update Håkan Jönsson Department of Energy and Technology

Department of Energy and Technology Air emissions Substance 1985 1996 2002 2005 2008 Reduction 85-08 Particles,ton 420 33 35 39 30 93% HCl, ton 8400 412 143 98 100% SOx, ton 3400 1121 790 310 154 95% NOx, ton 1463 1815 1904 2190 35% Hg, kg 3300 77 21 44 99% Cd, kg 400 8 15 (Cd+Tl) 21 (Cd+Tl) 6 (Cd+Tl) >98% Pb, kg 25 000 214 138 136 Dioxins, g 90 2 1.1 0,8 De totala utsläppen av kvicksilver var 37 , vilket motsvarade 0,0041 g per person. Detta kan jämföras med att 0,01 g kvicksilver per person årligen används till amalgam. Håkan Jönsson Department of Energy and Technology

GRAABS plant, Gothenburg Look for new one Håkan Jönsson Department of Energy and Technology

Waste incinerator - Uganda Håkan Jönsson Department of Energy and Technology

An advanced incineration system Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Department of Energy and Technology Flue gas - pollutants Particles Filter – electrostatic and/or textile filters NOx Fee 50 SEK/kg NOx (Total 688 milj SEK) Ammonia injection: 4 NH3 + 6 NO -> 5 N2 + 6 H2O; 4 NH3 + 4 NO +O2 -> 4 N2 + 6 H2O In furnace SNCR (Selctive Non-Cathalytic Reduction – 900-1050°C, 40-60% reduction) After furnace SCR (Selective Cathalytic Reduction – 300-400°C, 70-90% reduction) HCl Alkaline treatment (lime) SOx Heavy metals Removed with particles and acids Dioxin Attaches to active C, removed with particles at low temperature Håkan Jönsson Department of Energy and Technology

Flue gas cleaning - filters Cyclone Electro filter Textile filter (slangfilter) Scrubber Ill: Niro A/S Figure of cyclone Håkan Jönsson Department of Energy and Technology

Department of Energy and Technology Important parameters Temperature Retention time Oxygen Turbulence Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Sources of dioxin in Sweden Fig: Persson, 2005 Håkan Jönsson Department of Energy and Technology

Department of Energy and Technology Incineration plants Grate furnaces (Rosterpannor) Most common accepts large “particles” sensitive for varying energy content hard to control – much fuel in system grates need water cooling if waste is dry Fluidised bed roaster (Fluidbäddpanna) Easier to control and adjust to fuel Shreading necessary - (max 10 cm) Fluidised bed roaster Get a picture of a fluidized be roaster Håkan Jönsson Department of Energy and Technology Ill: Berman & Dille, Westinghouse

A modern incineration plant Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Department of Energy and Technology Flue gas cleaning Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Incineration hazardous waste Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Department of Energy and Technology Landfill Håkan Jönsson Department of Energy and Technology

The different stages of a landfill Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Department of Energy and Technology Water flows Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Land fill and water flows Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Department of Energy and Technology Requirements on liner Tid Flöde 200 år <5 l/m2, år 50 år <50 l/m2, år 1 år Fig: Persson, 2005 Håkan Jönsson Department of Energy and Technology

Hydrological considerations Fig: Persson, 2005 Håkan Jönsson Department of Energy and Technology

Collection of landfill gas 2003: 414 GWh to district heating, 26 WGWh electricity and 60 GWh not used. Fig: Persson, 2005 Håkan Jönsson Department of Energy and Technology

A well managed sanitary landfill Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Department of Energy and Technology Top and bottom liner Fig: Persson, 2005 Håkan Jönsson Department of Energy and Technology

Liners - hazardous waste Håkan Jönsson Department of Energy and Technology Fig: Persson, 2005

Landfill –biowaste banned EU Directive fully implemented 2008 Containment of waste Biowaste goes anaerobic Org C -> CH4 & CO2 Greenhouse gas, 50% collected (optimistic figure), 10% oxidised Risk of fire Sinking – top liner damaged – more leachate Nutrients and heavy metals leaches Aim: totally sealed Håkan Jönsson Department of Energy and Technology