Electrodialytic removal of Cd from biomass combustion fly ash: A new approach for sustinable re-cycling of bio ashes

Anne Juul Pedersen, Lisbeth M. Ottosen, Peter Simonsen, Terkel Christensen

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review


Due to a high concentration of Cd, biomass combustion fly ash often fails to meet the Danish legislative requirements for recycling on agricultural fields. In this work the potential of using the method Electrodialytic Remediation to reduce the concentration of Cd in different biomass combustion fly ashes was studied. Four fly ashes were investigated, originating from combustion of straw (two ashes), wood chips, and co-firing of wood pellets and fuel oil, respectively. One of the straw ashes had been pre-washed and was obtained suspended in water, the other ashes were obtained naturally dry. The initial Cd concentration in the ashes varied between 8.8 mg Cd/kg DM (co-firing ash) and 64 mg Cd/kg DM (pre-washed straw ash), and pH varied from 3.7 to 13.3. In spite of large differences in ash characteristics, the electrodialytic remediation experiments indicated a good remediation potential for all four ashes. Final Cd concentrations below 2.0 mg Cd/kg were reached in all ashes within 14 days of remediation and legislative requirements were met. After further optimization of the remediation process on the pre-washed straw ash, limiting concentrations were reached after only 48 hours of remediation. Hence the potential of the process seems very promising.
Original languageEnglish
Title of host publicationSecond World Biomass Conference. Biomass for Energy, Industry and Climate Protection : Proceedings of the World Conference held in Rome, Italy, 10-14 May 2004
EditorsW. P. M. Van Swaaij
Publication date2004
Publication statusPublished - 2004
Event2nd World conference and Exhibition on Biomass for Energy, Industry and Climate Protection - Rome, Italy
Duration: 1 Jan 2004 → …


Conference2nd World conference and Exhibition on Biomass for Energy, Industry and Climate Protection
CityRome, Italy
Period01/01/2004 → …

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