Community Research and Development Information Service - CORDIS


Co-firing of Biomass with Coal: Constraints and Role of Biomass Pre-Treatment

Funded under: FP6-JRC


There are many successful commercial co-firing installations, however various constraints can be encountered, especially in direct co-firing mode (which is the most common among co-firing systems), and with tendency to increase biomass/coal ratio, and use low quality biomass. These constraints can include handling, storage, milling and feeding problems, deposit formation (slagging and fouling), agglomeration, corrosion, erosion, and ash utilization issues. Most of the co-firing challenges originate from biomass properties The problems associated with co-firing systems can be addressed by various measures. One of them is application of biomass pre-treatment, which is an interesting option, as by modifying biomass properties, it addresses problems at their source.
The aim of this work is to provide an overview of possible constraints that can be encountered in systems cofiring coal with biomass, and identify biomass pre-treatment options with potential to address them. This was done by investigation of the literature.
The pre-treatment options discussed include sizing, drying, washing, pelletisation, torrefaction and pyrolysis of biomass, as well as combinations of some of them.
The most advanced form of bio-feedstock currently used in co-firing on commercial scale is biomass pretreated into pellets.
An interesting option is pyrolysis of biomass into pyrolysis oil, however this option cannot be applied in direct co-firing systems. It seems that biomass pre-treatment by combination of pelletisation with torrefaction might be an interesting option, as it could to even larger extent (than in case of conventional pellets) mitigate the problems related to high transportation and storage costs, handling, and milling of raw biomass.
The only single pre-treatment option with potential to mitigate problems (if encountered) with bed agglomeration, deposit formation (slagging and fouling) and corrosion was identified to be biomass leaching (washing).

Additional information

Authors: MACIEJEWSKA A, European Commission, Joint Research Centre, Institute for Energy, Petten (NL);VERINGA H, European Commission, Joint Research Centre, Institute for Energy, Petten (NL);SANDERS J, European Commission, Joint Research Centre, Institute for Energy, Petten (NL);PETEVES S, European Commission, Joint Research Centre, Institute for Energy, Petten (NL)
Bibliographic Reference: EUR 22461 EN (2006), 100 pp. Free of charge
Availability: Available from European Commission, JRC Knowledge Management Unit, Ispra (IT) Tel: +39 033278 9893 Fax: +39 033278 5409 E-mail: or Bruxelles (BE) Tel: +32 2 295 76 24 Fax: +32 2 299 63 22
ISBN: ISBN 92-79-02989-4
Record Number: 200718932 / Last updated on: 2007-03-16
Original language: en
Available languages: en