Chlorine in deposits during co-firing of biomass, peat, and coal in a full-scale CFBC boiler

Patrik Yrjas, BJ Skrifvars, Mikko Hupa, J Roppo, M Nylund, P Vainikka

    Research output: Chapter in Book/Conference proceedingConference contributionScientificpeer-review

    19 Citations (Scopus)

    Abstract

    Co-​combustion of coal with biomass or firing biomass alone is increasingly used as a first step to meet the Finnish commitments under the Kyoto agreement.  Fluidized bed combustors are commonly used when co-​firing, however, even if FBC have a wide tolerance for different fuel qualities, co-​combustion of biomass or firing biomass alone may lead to unwanted ash-​related problems. A deposit measurement campaign was done, at the 550 MWth biofueled CFB in Jakobstad, Finland.  During the campaign a total of 16 different fuel blends were burned.  The deposits were sampled with air-​cooled probes with detachable rings.  The deposits were sampled at two different locations, one where the flue gas temp. was about 730°C (probe surface temp. 540°C) and the second where the flue gas temp. was about 530°C (probe surface temp. 350°C)​.  From every deposit sample three elemental analyses were done - one from the wind side, one from the lee side, and one from an angle of about 50° from the wind side.  The analyses were done with a SEM​/EDX analyzer.  The fuels used during the measurement campaigns were sampled and analyzed.  In addn. to proximate and ultimate fuel anal. so called fuel fractionation was applied.  The fractionation method is based on selective leaching by water, ammonium acetate, and hydrochloric acid, consecutively.  After each leaching step the solns. are analyzed for the most important elements.  The method can be used to det. how the elements are bound in the fuel and how they may behave during combustion.  The anal. results from the measurement campaign and from the advanced fuel anal. were combined and are reported in this paper, with emphasis on the fate of chlorine.
    Original languageUndefined/Unknown
    Title of host publicationProceedings of the 18th International Conference on Fluidized Bed Combustion
    EditorsL Jia
    PublisherAmerican Society of Mechanical Engineers, ASME
    Pages679–687
    ISBN (Print)0-7918-4698-9
    Publication statusPublished - 2005
    MoE publication typeA4 Article in a conference publication
    Eventconference; 2005-05-22; 2005-05-25 - Toronto, Canada
    Duration: 22 May 200525 May 2005

    Conference

    Conferenceconference; 2005-05-22; 2005-05-25
    Period22/05/0525/05/05

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