dc.contributor.author | Li, Tian | |
dc.date.accessioned | 2015-05-08T10:47:25Z | |
dc.date.available | 2015-05-08T10:47:25Z | |
dc.date.issued | 2015 | |
dc.identifier.isbn | 978-82-326-0810-2 (printed version) | |
dc.identifier.isbn | 978-82-326-0811-9 (electronic version) | |
dc.identifier.issn | 1503-8181 | |
dc.identifier.uri | http://hdl.handle.net/11250/283365 | |
dc.description.abstract | Gasification of biomass is perceived as one of the most attractive thermochemical
processes to produce carbon neutral syngas that can be burned to release energy or used
as the building blocks for the production of value-added chemicals, especially liquid
fuel in the heavy transport sector. In the present thesis, both experimental and numerical
approaches were applied to investigate the behavior of biomass gasification at high
temperature and high heating rate conditions.
Devolatilization of biomass and conversion of solid char are two most important steps
in the gasification process. In order to assess the behavior of the rapid devolatilization
of biomass, biomass particles (forest residue, torrefied forest residue, Norwegian spruce,
and torrefied Norwegian spruce) were subjected to devolatilization experiments at 1073
K and 1473 K in an electrical heated drop tube reactor (DTR). A computational fluid
dynamic (CFD) simulation with a proposed two-competing rate devolatilization model
was also performed and compared to the experimental results. The conversion behavior
of forest residue char and torrefied forest residue char were further examined under
oxidation and gasification conditions at 1473 K and 1573 K in the same DTR. The
morphological analysis of the parent biomass and corresponding char were showed. In
addition, time-resolved data on compositional transformation of the biomass and char
were presented based on the metal tracer technics.
In parallel, Eulerian–Lagrangian CFD models were developed to study the overall
gasification process in two types of reactors: entrained-flow reactor (EFR) and
fluidized-bed reactor (FBR). Comprehensive CFD simulations were conducted to
evaluate the performance of biomass gasification in an EFR operating at 1273-1673 K.
The model was validated against a wide range of experimental data. Several influential
factors including reactor temperature, steam/carbon molar ratio, excess air ratio,
biomass type, and particle size were discussed. Regarding the FBR, particle flow pattern,
bed expansion, bed pressure drop and fluctuation frequency were compared by using
three different well-known inter-phase drag force correlations in a non-reactive
condition. Steam gasification in FBRs was analyzed by the CFD model developed from
a non-reactive study. Both qualitative and quantitative results were presented to reveal the effects of reactor temperature, steam/biomass ratio, and biomass injection position
on gasification of biomass. | nb_NO |
dc.language.iso | eng | nb_NO |
dc.publisher | NTNU | nb_NO |
dc.relation.ispartofseries | Doctoral thesis at NTNU;2015:77 | |
dc.relation.haspart | Paper 1:
Tian Li, Liang Wang, Xiaoke Ku, Berta Matas Güell, Terese Løvås, Christopher
R. Shaddix.
Experimental and modeling study of the effect of torrefaction on the rapid
devolatilization of biomass.
Is not included due to copyright | nb_NO |
dc.relation.haspart | Paper 2:
Tian Li, Manfred Geier, Liang Wang, Xiaoke Ku, Berta Matas Güell, Terese
Løvås, Christopher R. Shaddix.
Effect of torrefaction on physical properties and conversion behavior of high
heating rate char of forest residue.
Energy & Fuels, 29, 177-184, (2015) <a href="http://dx.doi.org/10.1021/ef5016044" target="_blank"> http://dx.doi.org/ 10.1021/ef5016044</a>
Copyright © 2015, American Chemical Society | |
dc.relation.haspart | Paper 3: Xiaoke Ku, Tian Li, Terese Løvås.
Eulerian−Lagrangian Simulation of Biomass Gasification Behavior in a High-
Temperature Entrained-Flow Reactor.
Energy & Fuels, 28, 5184–5196, (2014). <a href="http://dx.doi.org/10.1021/ef5010557" target="_blank"> http://dx.doi.org/10.1021/ef5010557</a>
Copyright © 2014 American Chemical Society | |
dc.relation.haspart | Paper 4: Ku, Xiaoke; Li, Tian; Løvås, Terese.
Influence of drag force correlations on periodic fluidization behavior in Eulerian-Lagrangian simulation of a bubbling fluidized bed. Chemical Engineering Science 2013 ;Volum 95. s. 94-106 <a href="http://dx.doi.org/10.1016/j.ces.2013.03.038" target="_blank"> http://dx.doi.org/10.1016/j.ces.2013.03.038</a>
This article is reprinted with kind permission from Elsevier, sciencedirect.com | |
dc.relation.haspart | Paper 5:
Ku, Xiaoke; Li, Tian; Løvås, Terese.
CFD-DEM simulation of biomass gasification with steam in a fluidized BEd reactor. Chemical Engineering Science 2015 ;Volum 122. s. 270-283 <a href="http://dx.doi.org/10.1016/j.ces.2014.08.045" target="_blank"> http://dx.doi.org/10.1016/j.ces.2014.08.045</a>
This article is reprinted with kind permission from Elsevier, sciencedirect.com | |
dc.title | Gasification of Biomass for Second Generation Biofuel Production | nb_NO |
dc.type | Doctoral thesis | nb_NO |
dc.subject.nsi | VDP::Technology: 500::Environmental engineering: 610 | nb_NO |