Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Influence of different shrinkage models and fuel geometry on heat transfer during rapid pyrolysis of solid biofuels
KTH, Tidigare Institutioner, Kemiteknik.
KTH, Tidigare Institutioner, Kemiteknik.
KTH, Tidigare Institutioner, Kemiteknik.
2002 (Engelska)Ingår i: Proceedings of the Finnish-Swedish FlameDays: Adapting Combustion Technology to New Fuels and Fuel Mixtures,september 2002, Vaasa, Finland: The Finnish and Swedish National Committees of The International Flame Research Foundation, IFRF, 2002Konferensbidrag, Publicerat paper (Refereegranskat)
Ort, förlag, år, upplaga, sidor
2002.
Nationell ämneskategori
Kemiteknik
Identifikatorer
URN: urn:nbn:se:kth:diva-7293OAI: oai:DiVA.org:kth-7293DiVA, id: diva2:12256
Konferens
The Finnish-Swedish FlameDays,september 2002, Vaasa, Finland
Anmärkning
QC 20100628Tillgänglig från: 2007-06-04 Skapad: 2007-06-04 Senast uppdaterad: 2012-01-03Bibliografiskt granskad
Ingår i avhandling
1. Modelling of the pyrolysis of large wood particles
Öppna denna publikation i ny flik eller fönster >>Modelling of the pyrolysis of large wood particles
2007 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

Wood is an interesting alternative to fossil fuels. It is CO2-neutral and widely available. However it is a difficult fuel to handle which features a low energy content. Thus technologies for wood thermal conversion need to be improved.

This work concerns the development of a comprehensive two-dimensional mathematical model describing the pyrolysis of large wood particles and its implementation in a Fortran program. The model has been continuously tested and improved by experimental results obtained in a reactor for single particle pyrolysis (SPAR) at the Division of Physical Chemistry at Göteborg University.

The first part of the thesis (Paper I) presents a kinetic study of the pyrolysis of large wood particles, based on experiments carried out in the SPAR. Three pyrolysis kinetic schemes were selected for later inclusion in a model featuring heat and mass transfer.

Paper II concerns the addition of a sub-model for heat and mass transfer to the three kinetic schemes. The resulting model for large wood particles has been tested against experiments in the SPAR. A scheme based on two competing reactions developed from experiments at low temperature pyrolysis in the SPAR was found to perform well but its empirical nature limits its validity to the experimental conditions of the SPAR. A scheme from the literature based on TGA experiments appeared promising, especially when planning to enhance it with secondary reactions.

Paper III deals with the development of shrinkage models for 2D cylindrical particles. The predicted mass loss, size variation and surface temperature were tested against experiments carried out in the SPAR. The shrinkage does not a?ect the pyrolysis rate or the surface temperature in the conditions prevailing in the SPAR.

Paper IV investigates the influence of different shrinkage models and the geometry on the heating rate of a shrinking particle. Shrinkage influences the heating rate positively by increasing the conductive

heat flow and negatively by decreasing the surface area of the particle. Therefore the net effect of shrinkage on the heating rate depends on the particle geometry and the location of shrinkage.

Paper V studies three di?erent models for wood drying under pyrolysis conditions.

The predicted surface temperature and global drying rate were compared with experimental results from pyrolysis experiments of wet particles in the SPAR. A model based on a first order kinetic evaporation rate was found to be the most interesting because of the quality of the prediction of the drying rate and the ease of implementation.

Ort, förlag, år, upplaga, sidor
Stockholm: KTH, 2007. s. vi, 97
Serie
Trita-CHE-Report, ISSN 1654-1081 ; 2007:37
Nyckelord
drying, modelling, pyrolysis, shrinkage, wood
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:kth:diva-4422 (URN)978-91-7178-709-5 (ISBN)
Disputation
2007-06-15, Sal F2, Lindstedtsvägen 26, KTH, SE-100 44, Stockholm, 10:00
Opponent
Handledare
Anmärkning
QC 20100624Tillgänglig från: 2007-06-04 Skapad: 2007-06-04 Senast uppdaterad: 2012-03-19Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Sök vidare i DiVA

Av författaren/redaktören
Bellais, MichelLiliedahl, TrulsSjöström, Krister
Av organisationen
Kemiteknik
Kemiteknik

Sök vidare utanför DiVA

GoogleGoogle Scholar

urn-nbn

Altmetricpoäng

urn-nbn
Totalt: 259 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf