1 / 35

Environmental Aspects of Alternative Materials in Road Construction

Learn about utilizing incinerator ash as road sub-base. Discover international projects, regulations, and risk assessments. Gain insight into standardization issues and material testing criteria.

karenhardman
Download Presentation

Environmental Aspects of Alternative Materials in Road Construction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nordisk Vejteknisk ForbundNordisk seminar omAlternative Materialer og Forstærkningsmetoder Miljømæssige aspekter ved anvendelse af affaldsforbrændingsslagger mv. som vejunderlag Environmental aspects of utilisation of MSW incinerator bottom ash and other alternative materials as subbase in road construction Ole Hjelmar DHI - Institut for Vand og Miljø 20. - 21. marts 2003, Eigtveds Pakhus, København

  2. Environmental aspects of alternative materials as sub-base in road construction • International projects and issues • Standardisation issues • Danish environmental regulations • Some Danish activities C-RES Centre for Waste Research/Center for Restprodukter www.c-res.dk Demonstration site for utilisation of MSWI BA as sub-base

  3. International projects and issues • ALT-MAT (1998 - 1999): EU - FP4- DGVII Unbound materials, recommendations for mechanical and environmental tests as well as assessment of environmental impact Contact: TRL, DRI, DHI, SGI, VTI, VTT • SAMARIS (2003 -2005): EU - FP5 - DG Energy & Transport - Better use of primary and secondary materials in road construction - Improved repair of corrosion suffering reinforced concrete structures Contact: DRI, DHI, VTI • Regulations None at EU level • Risk assessment Based on scenario and model calculations, leaching data, Landfill Directive as a model, ENV 12920

  4. ENV 12920: Characterisation of wasteMethodology for the determination of the leaching behaviour of waste under specified conditions • Definition of the problem and the solution sought • Description of the scenario • Description of the waste (material) • Determination of the influence of waste properties and specified scenario conditions on the release of contaminants • Modelling of leaching behaviour • Model validation • Conclusions

  5. Standardisation issues • CEN/TC 292: Characterisation of waste Tools and frameworks for environmental assessments, not only for “waste” e.g. EN 12457-parts 1 - 4 (batch leaching tests) ENV 12920 (methodology guideline) • CEN/TC 154: Aggregates Functional criteria/mechanical tests EN 1744-3 (a batch leaching test - a problem because it does not reflect the leaching mechanisms that control contaminant release)

  6. Danish Statutory Order regulating the use of alternative materials and soil for back-filling and road construction (January 2001) • Materials to be utilized must be on a short list included in the Statutory Order No. 655 of 27 June 2000 • A material must be thoroughly characterized to get on the short list • The following materials are currently on the short list: • MSWI bottom ash (TOC < 3 % (w/w)) • Coal bottom ash • Coal fly ash • Contaminated soil (inorganic contaminants)

  7. Danish Statutory Order regulating the use of alternative materials and soil for back-filling and road construction (January 2001) • Materials must be tested and are classified in 3 categories according to the test results • Materials are tested for “total contents” (category 1) and leaching of selected inorganic components (all categories) • Potential utilization of materials not complying with the category 1, 2 or 3 requirements is regulated by the Environmental Protection Act and will require a specific environmental impact assessment

  8. Danish Statutory Order regulating the use of alternative materials and soil for back-filling and road construction (January 2001) • Category 1: Unrestricted use • Category 2: Use with limited restrictions regarding cover and thickness • Category 3: Use with more severe restrictions regarding cover and thickness

  9. Danish Statutory Order regulating the use of alternative materials and soil for back-filling and road construction (January 2001) Test methods: • “Total” content: TOC and partial digestion with HNO3 and subsequent analyses for As, Cd, Cr (total), Cu, Hg, Ni, Pb, Zn and analysis for leachable Cr (VI) • Leaching: prEN 12457-3 (part 1) - batch leaching with DMW at L/S = 2 l/kg for 6 hrs and subsequent analysis of eluates for pH, conductivity, chloride, sulphate, Ca, Na, As, Ba, Cd, Cr (total), Cu, Hg, Mn, Ni, Pb, Zn

  10. Limit values for “total” contents

  11. Limit values for leaching

  12. Test results for 11 Danish incinerators

  13. Problematic components • Salts: Chloride, sulphate, sodium • Trace elements: Cu, Cr, Pb

  14. Copper leaching from MSWI BA

  15. Ageing experiment in full scale (stockpile) and pilot scale (approx. 100 kg aerated and moistened)

  16. Some potential treatment options for MSWI bottom ash • Washing with water • Chemical fixation/chemical mobilisation • Particle size separation • Ageing (hydration, carbonation, degradation), natural or accelerated • Biological treatment?

  17. C-RESCentre for Waste ResearchCenter for Restprodukter A centre without walls (1999 - 2003), partly funded by the Ministry of Science, Technology and Development Objectives: to develop environmentally and economically sustainable methods, products and technologies for characterisation and treatment of waste products/by-products to enable safe utilisation or landfilling Partners: DHI, DRI, DTU, DTI, RGS 90 A/S, Amagerforbrænding, Vestforbrænding, Babcock & Wilcox Vølund, DRH, SYSAV, Lunds Tekniske Universitet) Budget: Approximately 40 million DKK Contact: Ole Hjelmar, DHI (oh@dhi.dk) or www.c-res.dk

  18. Demonstration site for utilisation of MSWI bottom as sub-base in roadsLocated at Ydernæs - funded by DAFONET

  19. Demonstration site for utilisation of MSWI bottom as sub-base in roads

  20. Demonstration site for utilisation of MSWI bottom as sub-base in roadsCross-section of downstream edge of unit A

  21. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  22. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  23. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  24. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  25. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  26. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  27. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  28. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  29. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  30. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  31. Demonstration site for utilisation of MSWI bottom as sub-base in roadsYdernæs

  32. Initial water balance results

  33. Initial water balance results

  34. Initial water balance results

  35. Some conclusionsEnvironmental aspects of the use of alternative materials in roads • There is a substantial potential for the use of alternative materials in roads • The potential environmental impact must be assessed • Tools for assessment of the environmental impacts are available or under development or being validated • Environmental criteria for utilisation should be based on risk/impact assessments • The choice of test methods should be based on science and related to the risk assessment • International co-ordination of strategies and methods is necessary

More Related