• Ash and Deposit Formation in the Biomass Co-Fired CHP Plant

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This week a new paper has been published in the IFRF Combustion Journal (http://www.journal.ifrf.net), entitled:

“Ash and Deposit Formation in the Biomass Co-Fired Masnedø Combined Heat and Power Production Plant”



Flemming Frandsen
CHEC Research Centre
Department of Chemical Engineering
Technical University of Denmark
Building 229, DK-2800
Lyngby, Denmark

Email  ff@kt.dtu.dk

A series of biomass co-combustion tests were conducted at the Masnedø combined heat and power (CHP) production grate-fired boiler, Denmark, in the period Nov. 1998 %u2013 March 1999. The fuel feedstock mixtures applied were: Danish wheat straw (100 % on a thermal base), wheat straw wood chips (75 25 % on a thermal base), wheat straw olive stones (75 25 %), and wheat straw shea nuts (70 30 %).

During these combustion tests, air-cooled probes were exposed to the flue gas in the tertiary superheater. The metal surface temperature of the probes was kept constant at 500 ºC. Two probes were applied in each test, one was exposed for app. 1 h, the other was exposed for app. 18 hs.

Probe deposits formed have been mounted in epoxy, cross sectioned, polished and studied in a Scanning Electron Microscope (SEM). The 1 h probes are in general covered with a thin oxide scale and a thin ash layer on top of this, while the 18 h probes in addition to a multi-layer oxide scale also contain a thick ash layer. The ash layer consists of residual ash particles glued together by KCl (sometimes with a minor content of S also being present in this %u2019glue%u2019). There seems to be a tendency to be more ash particles in the outer ash layers formed when co-firing straw and other biomasses, compared to %u2019pure%u2019 straw-firing.

This paper provides an outline of fuel characteristics, mapping of the partitioning of K, S and Cl in the boiler, and differences in ash and deposit formation when co-firing biomasses in grate-fired boilers.

The full paper may be downloaded from the server, in the “New Papers” section (http://www.journal.ifrf.net/articles.html), by clicking on the Acrobat PDF icon alongside the title.

Publication in the Journal
The Editor-in-Chief (See associated article in this edition of the MNM) would like to remind all potential authors that publication in the Journal is open to all. If you have interesting results to publish in the field of, or related to, industrial combustion, we invite you to prepare a paper according to the guidelines given in the Author’s Guide on the website (

Papers may be regular “articles” (typically up to 20 pages) or Communications (typically up to 4/5 pages). Review papers can of course be longer. Remember that figures and graphics in general can be in full color. This advantage should be encouraged.

All manuscripts and associated files, proposed for publication should be sent by the Corresponding Author in a compressed/zip file, as an email attachment to journal@ifrf.net. This file should include a statement that the proposal’s content is unpublished material that has not being submitted for publication elsewhere. When an article by the author(s) is cited in the proposed article as “in press”, a copy of this article should accompany the proposed article and should be included in the compressed file.

The Editor-in-Chief looks forward to receiving your proposals.