Recovery of resources in Bottom Ash Status in Denmark Askedagen 2018, Energy Företagen, Stockholm, April 2018 Jens Kallesøe, Afatek A/S

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1 Recovery of resources in Bottom Ash Status in Denmark Askedagen 2018, Energy Företagen, Stockholm, April 2018 Jens Kallesøe, Afatek A/S

2 Overview 1. About Afatek 2. The key to recover fine metals 3. Next generation metal sorting plant 4. Minerals used in Road Construction 5. Conclusion Where are we in the Circular Economy?

3 About Afatek Owned by 5 public waste companies 6 WtE plants = tons of Bottom Ash = 40 % of the DK market (East Denmark) 3 sites for treatment of BA Adm+R&D: 6 empl. Operations: 12 empl. All Bottom Ash is recovered in Denmark: 6 % ferrous, 2 % nonferrous, minerals for road construction

4 The semi dry ash concept

5 Wet Bottom Ash can be dried down to level % H2O Recovery of fine metals Fine metals can be recovered from Bottom Ash only if the water content is as low as % We tested the screening We tested the metal separation We studied how the Bottom Ash dries out

6 Natural aging of Bottom Ash produce dry ash Tests showed that dried up ash of about % water can be screened down to 0,5 mm A maturation model was established - Chemical and Thermal Temperature drives out moisture Screening efficiency CO 2 consumption limiting factor? Water content decrease over time 0,5 mm Clean cut screening - grainsize 2-4 mm

7 We found copper, aluminium, silver and gold in the fines Rate and Composition of recovered metals Melting results NFE metals in band, [% of dry matter] 900 Hz 1,7% 1,6% 1,5% 1,4% 1,3% 1,2% 1 2 mm 1,1% 1,0% 2 4 mm 0,9% 0,8% 0,7% 0,6% 0,5 1 mm 0,5% 0,4% 0,3% 0,2% 0,1% 0,0% mm mm mm 1-2 mm 1-2 mm 1-2 mm 1-2 mm 2-4 mm 2-4 mm 2-4 mm 2-4 mm Light [%] 0,32% 0,31% 0,38% 0,80% 1,08% 0,44% 0,28% 0,38% 0,43% 0,80% 0,31% Heavy [%] 0,19% 0,14% 0,22% 0,68% 0,48% 0,37% 0,24% 0,37% 0,40% 0,61% 0,31% Gnmsn. 0,52% 0,52% 0,52% 1,10% 1,10% 1,10% 1,10% 0,90% 0,90% 0,90% 0,90% 0,1600% 0,1400% 0,1200% NFE metals in 0-50 mm [% of dry matter] 900 Hz 0,1000% 0,0800% 0,0600% 0,0400% 0,0200% 0,0000% Blandet Vest Vest mm 1-2 mm 2-4 mm Au 0,000001% 0,000002% 0,000004% Ag 0,000151% 0,000091% 0,000061% Sb 0,0000% 0,0000% 0,0000% Ni 0,0001% 0,0001% 0,0001% Sn 0,0006% 0,0004% 0,0002% Pb 0,0010% 0,0012% 0,0018% Zn 0,0010% 0,0012% 0,0018% Cu 0,0236% 0,0195% 0,0099% Al 0,1207% 0,0759% 0,0831% Al Cu Zn Pb Sn Ni Sb Ag Au

8 Next Generation Sorting Plant

9 The new Metal Sorting Plant New metal sorting plant in operation ,5 50 mm in 6 lines Wet Bottom Ash aged and dried Input: tons/y Investment: 8 mill EUR 3 lines for coarse bottom ash: 4-50 mm 3 lines for fine bottom ash: 0,5-4 mm

10 Metals can be recovered with an efficiency of about 80 % - even from wet bottom ash 2,5% Metal Recovery - 7 months - [% of raw bottom ash] SensorMachine 2,0% Copenhagen Plant = 2,0 % (3,3 % of dry sorted BA) Mobile Plant = 1,2 % Stainless 53% Alu 21% Cu 26% 1,5% 1,0% Eddy-Current 0,5% Cu 26% Alu 74% 0,0% KN B9, VF B12, KN B11, VF B14, NF B4, KN B12, VF B15, KN B1, VF B16, VFB17, VF B1, KN 2, VF 2, VF 4, VF 3, KN 3, KN 4, VF 5, KN 5, VF 6, AP B3, RE B4, RE 3, RE 5, AP 4, KV 2, AP 1, Alu Cu Stainless+Alu+Cu from SonsorMachine

11 We could almost double sales value of the metals Reference: Mobile plant New plant: Value increase: + 85 % (Alu: + 53 %, Cu: %)

12 Sorting Efficiency dependence on water content

13 Eddy-Current sorting technique + magnet taking fine iron Fe: 1-4 mm (paper clips) High speed camera

14 Eddy-Current sorting of Al and Cu-fraction (18-50 mm)

15 Eddy-Current sorting of Al and Cu-fraction (1-2 mm)

16 Sensor sorting of Stainless-fraction (18-50 mm)

17 RECOVERY OF MINERALS - develop the business and the environment

18 Use of Bottom Ash Gravel in Road Construction is approved by the state authorities, high way department and the Government Test road Nordhavn, Copenhagen Present: Limited traffic load Future: Unlimited traffic load Revision of standard for construction of roads, the Danish Road Directorate

19 Bottom ash substitute high quality gravel in road construction All bottom ash is tested and declared in accordance to mechanical and physical properties: Water content Particle size distribution Density and water content needed for efficient compaction Classification test for the constituents of coarse recycled aggregate Total Organic Content (TOC) % 25,0 120,0 100,0 80,0 60,0 40,0 20,0 Average grain size distribution for BA samples vs standard grain size distribution curve 0,0 0,001 0,01 0, Gennemsnit Grain size mm Standardkurve Water content w nat [%] Result: Since march 2012 all supplies of BA gravel from Afatek is declared Information about the construction product is now available for both the constructor and the controlling authority The bearing capacity test of the road in Copenhagen, may lead to use of BA gravel in higher road classes Denmark has a long tradition for using BA in road construction due to a clear national policy of using residues to substitute valuable virgin material 20,0 15,0 10,0 5,0-2,0 1,8 1,6 1,4 1,2 1,0 0,8 0,6 0,4 0,2 - Total Organic Content TOC (% dry matter)

20 CONCLUSION

21 The WtE & Bottom Ash Treatment prove its full potential when recovering metals from complex and small waste residues Efficient recovery system when waste residues are combined products (paper+metal, plastic+metal, wood+metal) Efficient recovery system when waste residues are too small to be recovered conventionally The minerals Bottom Ash Gravel is an excellent product to be used in Road Construction - substituting expensive gravel, approved by the National Highway Authority Fact is, that we in Denmark recover all Bottom Ash ( tons/year) nothing is landfilled. Result of a national policy on recovery of residues Ellen MacArthur Foundation Rethink the future Further research will be focused on improvement of metal recovery efficiency (incremental innovation) a short pay back time of the investment allow us to take in newest technology

22 Access to further information: Learn more about Afatek and our projects at - here you will also find access to our results and reports. Contact Jens Kallesøe Afatek A/S Selinevej Copenhagen jka@afatek.dk