Trends in utilizing WTE residues in Europe

Transcription

1 Trends in utilizing WTE residues in Europe INSTITUTE FOR TECHNICAL CHEMISTRY / WTERT 2010 Bi-Annual Meeting at Columbia University NEW YORK CITY, OCTOBER 7 & 8, 2010 J. Vehlow Institute for Technical Chemistry -Thermal Waste Treatment Division KIT University of the State of Baden-Wuerttemberg and National Research Center of the Helmholtz Association

2 MSW 1000 furnace / boiler filter scrubber < Fe non Fe (wet with effluents) (wet without effluents) (dry) flows of solid masses in a MSWI plant in kg

3 fundamentals of WtE residue management in Europe almost uniform regulations for disposal (in EU based on Council Decision 2003/32/EC) no common standards or recommendations for utilisation bottom ashes are generally classified as non hazardous depending on national regulations they are either landfilled or utilised boiler ash and filter ashes are classified as hazardous waste APC residues are also classified as hazardous waste

4 selected elements in bottom ash and lithosphere

5 important parameters for bottom ash management total organic carbon chemical composition leaching stability - access criterion for landfills - main quality parameter for utilisation mechanical parameters in case of utilisation

6 selected leaching compliance tests test EN EN / DIN EN TVA NEN 7243 NEN 7243 country EU Germany Switzerland The Netherlands The Netherlands type serial batch batch serial batch column serial batch max- particle size (mm) leachant H 2 O H 2 O number of steps L/S (l/kg) per step contact time agitation 10 actual size H 2 O CO 2 saturated H 2 O 1 mol/l HNO 3 1 st step: ph=7 2 nd step: ph= st step: 2 2 nd step: 8 1 st step: 6 h 2 nd step: 18 h end over end/ roller table h 24 h per step 16 d 3 h end over end/ roller table CO 2 injection leachant pumped through column stirring

7 Cr Ni Cu Zn Cd Pb release in mg/kg TVA DIN EN leaching of bottom ash using the Swiss and the German test

8 regulations for bottom ash management in Germany disposal Ordinance on Environmentally Compatible Storage of Waste from Human Settlements (AbfAblV, 2001) utilisation LAGA M19 - investigation of raw bottom ash LAGA M20 - regulations for utilisation leaflets of federal states, road construction regulations (FGVS),...

9 German landfill and utilisation standards parameter dimen sion landfill landfill utilisation class 1 class 2 (LAGA M20) LOI % 3 5 TOC % DIN EN sol. fraction % 3 6 el. cond. ms/m 1,000 5, Cl mg/l 250 Ni mg/l Cu mg/l Zn mg/l Cd mg/l Pb mg/l strength vane shear strength kn/m axial deformation % uniaxial compr. strength kn/m

10 HCl water bottom ash tank HCl pump filter to scrubber water deslagger filter to bunker water press. air sedimentation process water bottom ash washing at MVR Hamburg

11 raw ash <32 mm sieve 32mm >32 mm sieve 10mm >10 mm impact crusher <10 mm air classifier ferrous scrap nonferrous scrap magnetic separation eddy current separation magnetic separation eddy current separation ferrous scrap nonferrous scrap belt scale belt scale sieve 32mm >32 mm disposal to furnace storage for maturing utilisation (source: Zwahr 2005) treatment of bottom ash for utilisation (Hamburg)

12 importance of metal separation drivers unwanted effects in application (H 2 formation, swelling) economy, esp. for non-ferrous metals status almost all plants practice ferrous scrap separation most plants implement eddy current systems conventional systems remove % of ferrous and 30 % of non ferrous scrap many plants try to do special separation from fine fractions in Switzerland dry ash discharge is considered

13 conveyer belt magnet permanent magnet bottom ash conveyer magnetic fraction magnetic fraction magnetic drum separator non-magnetic fraction over-band system drum system magnetic separation systems

14 eddy current separator sensor operated separator new metal separation systems

15 DEV S4 results of bottom ash samples

16 bottom ash management in selected countries

17 bottom ash management in selected countries year production [Mg/a] utilisation [%] specifics Austria , 'slag concrete for landfill' Belgium , secondary building material Czech Republic ,000 0 landfilling Denmark , % road construction Finland ,000 0 landfilled France ,700, civil engineering Germany ,740, mainly road construction Hungary ,000 0 landfilling Italy , landfilling Netherlands ,500, building material Norway ,000 0 landfilling Portugal ,000 0 landfilling Spain ,693 5 road construction Sweden , few cases of road construction Switzerland ,000 0 landfilling United Kingdom , building material

18 PCDD/F concentration in mg/kg (PCDD/F in ng[te]/kg) selected pollutants in bottom and filter ash

19 filter ash management problem high loads of salts, low volatile organics, and heavy metals status hazardous landfill still preferred disposal practise so-called utilisation for - backfilling of salt mines in Germany - filling of an old quarry on Norwegian Island Langøya utilisation as asphalt filler in The Netherlands especially in Switzerland acid metal extraction (FLUWA) - option of thermal treatment of residues and metal recovery

20 filter ash management in selected countries country year production comments [Mg] Austria ,000 mainly salt mine backfilling, hazardous landfill Belgium ,000 solidification and haz. landfill Czech Republic , hazardous landfill, 1000 underground mine Denmark , % recycled (salt mine after special treatment) France 400,000 Germany ,000 utilisation in salt mine, minor amount haz. landfill Hungary ,585 hazardous landfill Italy ,000 hazardous landfill Netherlands ,200 50% utilised in mines and as asphalt filler Portugal ,000 inertisation before hazardous landfill Spain ,420 hazardous. landfill Sweden ,000 landfilling. partly utilisation in Norway (Langoya) Switzerland ,000 metal extraction, landfill United Kingdom ,125 hazardous landfill

21 boiler filter 1. scrubber 2. scrubber Hg recovery grate ash + 3R product extraction binder extrusion liquid heavy metal recovery scheme of the 3R Process

22 APC residue management problem high loads of salts Hg heavy metals & organics in case of dry scrubbing without separate fly ash removal status hazardous landfill still preferred disposal practise so-called utilisation in mines recovery of HCl and gypsum in few plants

23 NaOH tank offgas halogen scrubber AC filter from CaCl 2 evaporation pre-evaporator fluoride separator distillation column evaporator absorber dm water acid scrubber effluent strip column filter Na 2 S 2 O 3 air NaOCl steam condensate mixed salts AlCl 3 distillate to CaCl 2 evaporation HCl recovery at MVR Hamburg (Germany)

24 conclusions bottom ashes are to an increasing extent utilized as building material secondary treatment pays only if a high quality of the products can be achieved fly ashes hazardous landfill depending on availability backfilling of mines or quarries inertisation with metal recovery may come APC residues recovery in case of Neutrec process few cases of HCl, NaCl, and gypsum recovery else: see fly ashes