Environmental Science and Pollution Research

, Volume 24, Issue 17, pp 14770–14781 | Cite as

Ashes from fluidized bed combustion of residual forest biomass: recycling to soil as a viable management option

  • Nuno C. Cruz
  • Sónia M. RodriguesEmail author
  • Lina Carvalho
  • Armando C. Duarte
  • Eduarda Pereira
  • Paul F.A.M. Römkens
  • Luís A.C. Tarelho
Research Article


Although bottom ash (BA) [or mixtures of bottom and fly ash (FA)] from clean biomass fuels is currently used as liming agent, additive for compost, and fertilizer on agricultural and forest soils in certain European countries, in several other countries most of the ashes are currently disposed in landfills. This is due to both a lack of a proper classification of the materials and of regulatory barriers.

Chemical characterization including analysis of an array of potentially toxic elements (PTEs) proved that over 100,000 tons of BA currently landfilled every year in Portugal actually complied with legal limits for PTEs for soil fertilizers applied in other countries. Pot experiments were conducted, testing three dosages of BA and FA (1, 2.5, and 5%, in weight) in three mining soils with different properties. Additions of ash materials to soils led to an increase in the pore water pH relative to control pots (0% of ash added) and had a clear impact on DOC and on the solubilization of both macro- and micronutrients (notably Cu).

The results from the case study using BA and FA from a Portuguese biomass thermal power plant demonstrate that it is imperative to further develop a regulatory framework to alleviate technological and environmental barriers for biomass ash utilization as raw material for fertilizers and/or soil liming agent, in accordance with the goals of the circular economy. A more harmonized view on how to assess the merits and risks of the re-use of these materials is also needed.


Portugal Bottom ash Fly ash Recycling Soil amendment 



This work was supported by European Funds through “Programa Operacional Factores de Competitividade—COMPETE” and by National Funds through the Portuguese Science Foundation (FCT) within project PEst-C/MAR/LA0017/2013. S.M.R. acknowledges the financial support from FCT (Project IF/01637/2013). The authors also acknowledge the financial support of both FCT and COMPETE through Project no. FCOMP-01-0124-FEDER-02800 (FCT PTDC/AGR-PRO/4091/2012) and of the European Commission through Project LIFE14 ENV/PT/000369.

Supplementary material

11356_2017_9013_MOESM1_ESM.docx (2 mb)
ESM 1 (DOCX 2053 kb)


  1. Dahl O, Nurmesniemi H, Pöykiö R, Watkins G (2009) Comparison of the characteristics of bottom ash and fly ash from a medium-size (32 MW) municipal district heating plant incinerating forest residues and peat in a fluidized-bed boiler. Fuel Process Technol 90:871–878CrossRefGoogle Scholar
  2. Dahl O, Nurmesniemi H, Pöykiö R, Watkins G (2010) Heavy metal concentrations in bottom ash and fly ash fractions from a large-sized (246 MW) fluidized bed boiler with respect to their Finnish forest fertilizer limit values. Fuel Process Technol 91:1634–1639CrossRefGoogle Scholar
  3. Demeyer A, Nkana JCV, Verloo MG (2001) Characteristics of wood ash and influence on soil properties and nutrient uptake: an overview. Bioresour Technol 77:287–295CrossRefGoogle Scholar
  4. Etiégni L, Campbell AG (1991) Physical and chemical characteristics of wood ash. Bioresour Technol 37:173–178CrossRefGoogle Scholar
  5. EC (European Commission). 2011. Report from the commission to the European Parliament, the council, the European economic and social committee and the committee of the regions on the thematic strategy on the prevention and recycling of waste. COM/11/13. 19/1/2011, Brussels.Google Scholar
  6. EC (European Commission). 2015. Closing the loop: Commission adopts ambitious new Circular Economy Package to boost competitiveness, create jobs and generate sustainable growth. IP/15/6203. 2/12/2015. Brussels.Google Scholar
  7. EC (European Commission) (2016a) Ordinance reorganising sewage sludge recovery (Sewage Sludge Ordinance). TRIS/16/02979. 27/12/2016. Brussels.Google Scholar
  8. EC (European Commission) (2016b) Proposal for a regulation of the European parliament and the council - laying down rules on the making available on the market of CE marked fertilizing products and amending Regulations (EC) No 1069/2009 and (EC) No 1107/2009. COM (2016), 157. 17/03/2016. Brussels.Google Scholar
  9. Gianfreda L (2015) Enzymes of importance to rhizosphere processes. J Soil Sci Plant Nutr 15(2):283–306Google Scholar
  10. Huang H, Campbell AG, Folk R, Mahler RL (1992) Wood ash as a soil additive and liming agent for wheat. Field studies Communications in Soil Science and Plant Analysis 23:25–33CrossRefGoogle Scholar
  11. Ingerslev M, Skov S, Sevel L, Pedersen LB (2011) Element budgets of forest biomass combustion and ash fertilisation—a Danish case-study. Biomass Bioenergy 35:2697–2704CrossRefGoogle Scholar
  12. Insam H, Knapp BA (2011) Recycling of biomass ash, first edn. Springer-Verlag, BerlinCrossRefGoogle Scholar
  13. Modolo RC, Ferreira VM, Tarelho LA, Labrincha JA, Senff L, Silva L (2013) Mortar formulations with bottom ash from biomass combustion. Constr Build Mater 45:275–281CrossRefGoogle Scholar
  14. Modolo RCE, Tarelho LAC, Teixeira ER, Ferreira VM, Labrincha JA (2014) Treatment and use of bottom bed waste in biomass fluidized bed combustors. Fuel Process Technol 125:170–181CrossRefGoogle Scholar
  15. Modolo RCE, Silva T, Senff L, Tarelho LAC, Labrincha JA, Ferreira VM, Silva L (2015) Bottom ash from biomass combustion in BFB and its use in adhesive-mortars. Fuel Process Technol 129:192–202CrossRefGoogle Scholar
  16. Montes-Hernandez G, Pérez-López R, Renard F, Nieto JM, Charlet L (2009) Mineral sequestration of CO2 by aqueous carbonation of coal combustion fly-ash. J Hazard Mater 161:1347–1354CrossRefGoogle Scholar
  17. Obernberger I, Supancic K (2009) Possibilities of ash utilization from biomass combustion plants. In: Proceedings of the 17th European Biomass Conference & Exhibition. Hamburg, GermanyGoogle Scholar
  18. Ohno T, Erich MS (1993) Incubation-derived calcium carbonate equivalence of papermill boiler ashes derived from sludge and wood sources. Environ Pollut 79:175–180CrossRefGoogle Scholar
  19. Osakia M, Watanabe T, Tadano T (1997) Beneficial effect of aluminum on growth of plants adapted to low pH soils. Soil Sci Plant Nutr 43:551–563CrossRefGoogle Scholar
  20. Pandey VC, Singh N (2010) Impact of fly ash incorporation in soil systems. Agric Ecosyst Environ 136:16–27CrossRefGoogle Scholar
  21. Pels JR, Sarabèr AJ (2011) Utilization of Biomass Ashes. In: Grammelis P (ed) Solid Biofuels for Energy: A Greenhouse Gas Alternative. 1st edn. Springer-Verlag, London pp 219-235Google Scholar
  22. Pels JR, de Nie DS, Kiel JHA (2005) Utilization of ashes from biomass combustion and gasification. In: Proceedings of the 14th European biomass Conference & Exhibition. France, ParisGoogle Scholar
  23. Rajamma R, Ball RJ, Tarelho LAC, Allen GC, Labrincha JA, Ferreira VM (2009) Characterisation and use of biomass fly ash in cement-based materials. J Hazard Mater 172:1049–1060CrossRefGoogle Scholar
  24. Ribbing C (2007) Environmentally friendly use of non-coal ashes in Sweden. Waste Manag 27:1428–1435CrossRefGoogle Scholar
  25. Rodrigues SM, Henriques B, Ferreira da Silva E, Pereira ME, Duarte AC, Römkens PFAM (2010b) Evaluation of an approach for the characterization of reactive and available pools of twenty potentially toxic elements in soils: part I—the role of key soil properties in the variation of contaminants’ reactivity. Chemosphere 81:1549–1559CrossRefGoogle Scholar
  26. Rodrigues SM, Henriques B, Ferreira da Silva E, Pereira ME, Duarte AC, Groenenberg JA, Römkens PFAM (2010a) Evaluation of an approach for the characterization of reactive and available pools of 20 potentially toxic elements in soils: part II—solid-solution partition relationships and ion activity in soil solutions. Chemosphere 81:1560–1570CrossRefGoogle Scholar
  27. Ronen E (2007) Micro-elements in agriculture. Practical Hydroponics & Greenhouses 6:39–48Google Scholar
  28. Smith JL, Doran JW (1996) Measurement and use of pH and electrical conductivity for soil quality analysis. In: Doran JW, Jones AJ (eds) Methods for assessing soil quality. Soil Science Society of America, Wisconsin, pp 169–185Google Scholar
  29. Tack FMG (2010) Trace elements: general soil chemistry, principles and processes. In: Hooda PS (ed) Trace elements in soils. John Wiley & Sons Ltd, Chichester, pp 9–32CrossRefGoogle Scholar
  30. Tarelho LAC, Neves DSF, Matos MAA (2011) Forest biomass waste combustion in a pilot-scale bubbling fluidised bed combustor. Biomass Bioenergy 35:1511–1523CrossRefGoogle Scholar
  31. Tarelho, L.A.C., Teixeira, E.R., Silva, D.F.R., Modolo, R.C.E., Silva, J.J.F., 2012. Characteristics, management, and applications of ashes from thermochemical conversion of biomass to energy. Proceedings of the World Bioenergy 2012, Conference and Exhibition on Biomass for Energy. Jonkoping, Sweden.Google Scholar
  32. Tarelho LAC, Teixeira ER, Silva DFR, Modolo RCE, Labrincha JA, Rocha FJFT (2015) Characteristics of distinct ash flows in a biomass thermal power plant with bubbling fluidised bed combustor. Energy 90:387–402CrossRefGoogle Scholar
  33. Ukwattage NL, Ranjith PG, Bouazza M (2013) The use of coal combustion fly ash as a soil amendment in agricultural lands (with comments on its potential to improve food security and sequester carbon). Fuel 109:400–408CrossRefGoogle Scholar
  34. Van Eijk, R.J., Obernberger, I., Supancic, K., 2012. Options for increased utilization of ash from biomass combustion and co-firing. KEMA Report, Arnhem, Netherlands.Google Scholar
  35. Van Swaaij, W., Kersten, S., Paltz, W., 2015. Biomass power for the world: transformations to effective use—6th volume, first ed. Pan Stanford Publishing PTE. Ltd., Singapore.Google Scholar
  36. Vassilev SV, Baxter D, Andersen LK, Vassileva CG (2013) An overview of the composition and application of biomass ash. Part 2. Potential utilisation, technological and ecological advantages and challenges. Fuel 105:19–39CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Nuno C. Cruz
    • 1
  • Sónia M. Rodrigues
    • 1
    Email author
  • Lina Carvalho
    • 2
  • Armando C. Duarte
    • 1
  • Eduarda Pereira
    • 1
  • Paul F.A.M. Römkens
    • 3
  • Luís A.C. Tarelho
    • 4
  1. 1.CESAM & Department of ChemistryUniversity of AveiroAveiroPortugal
  2. 2.LCA—Central Laboratory of AnalysisUniversity of AveiroAveiroPortugal
  3. 3.Wageningen University and Research CentreWageningenThe Netherlands
  4. 4.CESAM & Department of Environment and PlanningUniversity of AveiroAveiroPortugal

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