Thermal Separation and Leaching of Valuable Elements from Waste-Derived Ashes
Recovery of trace elements from different industrial waste streams is important in realizing the goals of the circular economy. Ash streams from waste combustion can contain high levels of both toxic and valuable trace elements. These elements can be separated during the combustion process based on volatilization and condensation, as well as being separated in post-combustion processes, through thermal or leaching treatment. In this study, an overview is given of the thermal methods for recovery of valuable elements from ash fractions derived from waste incineration. In addition, a case study is presented of the behaviour of ash-forming elements in combustion of MSW and demolition wood, with special focus on the elements Co, Cu, and Sb. In conclusion, it is shown that thermodynamic modeling of high temperature processes can be a useful tool to predict ash behavior both during combustion and in the post combustion treatment of the ash.
KeywordsAsh treatment Thermodynamic modeling Waste incineration Thermal processing
The study was performed within the ARVI-Material Value Chains Research Program, coordinated by CLIC Innovation Oy and financed by Tekes – the Finnish Funding Agency for Innovation.
- 4.Whiticar DM, Ralph J (2011) Waste to energy. A Technical Review of Municipal Solid Waste Thermal Treatment Practices—Final Report. Stantec Consulting Ltd, p 339. http://www.env.gov.bc.ca/epd/mun-waste/reports/pdf/BCMOE-WTE-Emissions-final.pdf
- 6.C. IAWG (International Ash Working Group) AJ, Eighmy TT, Hartle´n O, Kosson D, Sawell SE, van der Sloot H, Vehlow J (1997) Municipal solid waste incinerator residues. studies in environmental science. ElsevierGoogle Scholar
- 12.Obernberger I, Biedermann F (1997) Fractionated Heavy metal separation in biomass combustion plants-possibilities, technological approach, experiences. In: The impact of mineral impurities in solid fuel combustion, Engineering Foundation, New York, United States, Kona, Hawaii, USAGoogle Scholar
- 14.Kangas P, Koukkari P, Lindberg D, Hupa M (2014) Modelling black liquor combustion with the constrained Gibbs energy method. J Sci Technol For Prod Process 3:6–15Google Scholar
- 18.Vainio E, Lindberg D, Yrjas P (2015) Characterisation and on-line measurements of ashes—continuous leaching analysis of ashes. Arvi - material value chains, project report. https://portal.cleen.fi/_layouts/IWXmlPublications.aspx?Source=ARVI&FileId=265
- 19.Lindberg D, Vainio E, Yrjas P (2015) Critical review of thermodynamic data for heavy metals in aqueous solutions and thermodynamic calculations of solubility of heavy metal compounds in ash. Arvi—material value chains, project report. https://portal.cleen.fi/_layouts/IWXmlPublications.aspx?Source=ARVI&FileId=266
- 20.Laine-Ylijoki J, Bacher J, Tommi Kaartinen K, Korpijärvi M, Wahlström M, Castell-Rüdenhausen z (2015) Review on Elemental Recovery Potential of Ashes. Arvi—material value chains, project report. https://portal.cleen.fi/_layouts/IWXmlPublications.aspx?Source=ARVI&FileId=220
- 21.Vainio E, Hupa E, Eriksson J-E, Lindberg D, Yrjas P (2017) Continuous leaching analysis of ashes. Arvi—material value chains, project report. https://portal.cleen.fi/_layouts/IWXmlPublications.aspx?Source=ARVI&FileId=689