Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials

In this study we present findings from investigations into interactions between biomass tar and two iron based oxygen carrier materials (OCMs) designed for chemical-looping applications: a 100% Fe _2 O _3 (100Fe) OCM and a 60 wt% Fe _2 O _3 /40 wt% Al _2 O _3 (60Fe40Al) OCM. A novel 6 kW _e two-stag...

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Main Authors: Matthew E Boot-Handford, Nick Florin, Paul S Fennell
Format: Article
Language:English
Published: IOP Publishing 2016-01-01
Series:Environmental Research Letters
Subjects:
Online Access:https://doi.org/10.1088/1748-9326/11/11/115001
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author Matthew E Boot-Handford
Nick Florin
Paul S Fennell
author_facet Matthew E Boot-Handford
Nick Florin
Paul S Fennell
author_sort Matthew E Boot-Handford
collection DOAJ
description In this study we present findings from investigations into interactions between biomass tar and two iron based oxygen carrier materials (OCMs) designed for chemical-looping applications: a 100% Fe _2 O _3 (100Fe) OCM and a 60 wt% Fe _2 O _3 /40 wt% Al _2 O _3 (60Fe40Al) OCM. A novel 6 kW _e two-stage, fixed-bed reactor was designed and constructed to simulate a chemical-looping combustion (CLC) process with ex situ gasification of biomass. Beech wood was pyrolysed in the first stage of the reactor at 773 K to produce a tar-containing fuel gas that was used to reduce the OCM loaded into the 2nd stage at 973 K. The presence of either OCM was found to significantly reduce the amount of biomass tars exiting the reactor by up to 71 wt% compared with analogous experiments in which the biomass tar compounds were exposed to an inert bed of sand. The tar cracking effect of the 60Fe40Al OCM was slightly greater than the 100Fe OCM although the reduction in the tar yield was roughly equivalent to the increase in carbon deposition observed for the 60Fe40Al OCM compared with the 100Fe OCM. In both cases, the tar cracking effect of the OCMs appeared to be independent of the oxidation state in which the OCM was exposed to the volatile biomass pyrolysis products (i.e. Fe _2 O _3 or Fe _3 O _4 ). Exposing the pyrolysis vapours to the OCMs in their oxidised (Fe _2 O _3 ) form favoured the production of CO _2 . The production of CO was favoured when the OCMs were in their reduced (Fe _3 O _4 ) form. Carbon deposition was removed in the subsequent oxidation phase with no obvious deleterious effects on the reactivity in subsequent CLC cycles with reduction by 3 mol% CO.
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spelling doaj.art-a47a0f7acc514fc88b834e34a1a6e28e2023-08-09T14:15:39ZengIOP PublishingEnvironmental Research Letters1748-93262016-01-01111111500110.1088/1748-9326/11/11/115001Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materialsMatthew E Boot-Handford0Nick Florin1Paul S Fennell2Department of Chemical Engineering, Imperial College London, SW7 2AZ, LondonGrantham Institute for Climate Change, Imperial College London, SW7 2AZ, London; Institute for Sustainable Futures, University of Technology Sydney , NSW 2007, AustaliaDepartment of Chemical Engineering, Imperial College London, SW7 2AZ, LondonIn this study we present findings from investigations into interactions between biomass tar and two iron based oxygen carrier materials (OCMs) designed for chemical-looping applications: a 100% Fe _2 O _3 (100Fe) OCM and a 60 wt% Fe _2 O _3 /40 wt% Al _2 O _3 (60Fe40Al) OCM. A novel 6 kW _e two-stage, fixed-bed reactor was designed and constructed to simulate a chemical-looping combustion (CLC) process with ex situ gasification of biomass. Beech wood was pyrolysed in the first stage of the reactor at 773 K to produce a tar-containing fuel gas that was used to reduce the OCM loaded into the 2nd stage at 973 K. The presence of either OCM was found to significantly reduce the amount of biomass tars exiting the reactor by up to 71 wt% compared with analogous experiments in which the biomass tar compounds were exposed to an inert bed of sand. The tar cracking effect of the 60Fe40Al OCM was slightly greater than the 100Fe OCM although the reduction in the tar yield was roughly equivalent to the increase in carbon deposition observed for the 60Fe40Al OCM compared with the 100Fe OCM. In both cases, the tar cracking effect of the OCMs appeared to be independent of the oxidation state in which the OCM was exposed to the volatile biomass pyrolysis products (i.e. Fe _2 O _3 or Fe _3 O _4 ). Exposing the pyrolysis vapours to the OCMs in their oxidised (Fe _2 O _3 ) form favoured the production of CO _2 . The production of CO was favoured when the OCMs were in their reduced (Fe _3 O _4 ) form. Carbon deposition was removed in the subsequent oxidation phase with no obvious deleterious effects on the reactivity in subsequent CLC cycles with reduction by 3 mol% CO.https://doi.org/10.1088/1748-9326/11/11/115001chemical-looping combustionbiomasstarchemical-looping reformingbio-syngas upgradingBECCS
spellingShingle Matthew E Boot-Handford
Nick Florin
Paul S Fennell
Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials
Environmental Research Letters
chemical-looping combustion
biomass
tar
chemical-looping reforming
bio-syngas upgrading
BECCS
title Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials
title_full Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials
title_fullStr Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials
title_full_unstemmed Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials
title_short Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials
title_sort investigations into the effects of volatile biomass tar on the performance of fe based clc oxygen carrier materials
topic chemical-looping combustion
biomass
tar
chemical-looping reforming
bio-syngas upgrading
BECCS
url https://doi.org/10.1088/1748-9326/11/11/115001
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