Biomass gasification for the production of methane

Pavlina Nanou

Research output: ThesisPhD Thesis - Research UT, graduation UTAcademic

917 Downloads (Pure)

Abstract

Biomass is very promising as a sustainable alternative to fossil resources because it is a renewable source that contains carbon, an essential building block for gaseous and liquid fuels. Methane is the main component of natural gas, which is a fuel used for heating, power generation and transportation. In The Netherlands, the contribution of natural gas to the primary energy consumption is almost 50% (Source: Energy Research Centre of The Netherlands [ECN]) and it is a fuel with a well-developed pipeline distribution network and infrastructure. There are different biomass conversion routes to methane depending on the water content of the biomass feed. The thermochemical conversion route to convert relatively dry biomass into methane is conventionally envisaged in a two-step process: In the first step, biomass is gasified (with heat demand, high T / low P) and in the second step methane is formed (with heat release, low T / high P) in a separate reactor. In this configuration there is no heat integration possible between the two process stages. In this thesis, a new gasification concept is investigated, termed self-gasification, that overcomes, inter alia, the issue of heat integration. The concept entails an intermediate temperature (700-800°C) and pressure (25-35 bar) steam gasifier, where recycled ash components -contained in the biomass itself- serve as potential “catalysts” for char (from biomass pyrolysis) gasification, methane formation, gas conditioning and tar cracking. The focus of the present research lies on process evaluation and study of the influence of biomass ashes on the aforementioned reactions. Ashes are present in different concentrations in targeted biomass feeds for gasification; ranging from ~0.5 wt.% in “clean wood” to ~15 wt.% in chicken litter. For that reason alone, results presented in this thesis are not limited to the self-gasification concept where methane is the final product, but give valuable information for other biomass gasification processes as well. Subjects such as gasification under pressure, methane formation and the effect of naturally occurring ash in biomass are dealt with in this thesis. The concept is now ready to be studied in an integrated bench-scale unit for further evaluation.
Original languageEnglish
Awarding Institution
  • University of Twente
Supervisors/Advisors
  • Kersten, Sascha R.A., Supervisor
  • van Swaaij, Willibrordus P.M., Supervisor
  • van Rossum, G., Advisor
Award date17 May 2013
Place of PublicationEnschede
Publisher
Print ISBNs978-90-365-3543-4
DOIs
Publication statusPublished - 17 May 2013

Fingerprint

Gasification
Methane
Biomass
Ashes
Natural gas
Natural gas conditioning
Bioconversion
Tar
Liquid fuels
Electric power distribution
Water content
Power generation
Wood
Pyrolysis
Steam
Energy utilization
Pipelines
Heating
Catalysts
Carbon

Keywords

  • METIS-296480
  • IR-85988

Cite this

Nanou, Pavlina. / Biomass gasification for the production of methane. Enschede : Universiteit Twente, 2013. 173 p.
@phdthesis{31940aba68f94973a3f403f825cc1b39,
title = "Biomass gasification for the production of methane",
abstract = "Biomass is very promising as a sustainable alternative to fossil resources because it is a renewable source that contains carbon, an essential building block for gaseous and liquid fuels. Methane is the main component of natural gas, which is a fuel used for heating, power generation and transportation. In The Netherlands, the contribution of natural gas to the primary energy consumption is almost 50{\%} (Source: Energy Research Centre of The Netherlands [ECN]) and it is a fuel with a well-developed pipeline distribution network and infrastructure. There are different biomass conversion routes to methane depending on the water content of the biomass feed. The thermochemical conversion route to convert relatively dry biomass into methane is conventionally envisaged in a two-step process: In the first step, biomass is gasified (with heat demand, high T / low P) and in the second step methane is formed (with heat release, low T / high P) in a separate reactor. In this configuration there is no heat integration possible between the two process stages. In this thesis, a new gasification concept is investigated, termed self-gasification, that overcomes, inter alia, the issue of heat integration. The concept entails an intermediate temperature (700-800°C) and pressure (25-35 bar) steam gasifier, where recycled ash components -contained in the biomass itself- serve as potential “catalysts” for char (from biomass pyrolysis) gasification, methane formation, gas conditioning and tar cracking. The focus of the present research lies on process evaluation and study of the influence of biomass ashes on the aforementioned reactions. Ashes are present in different concentrations in targeted biomass feeds for gasification; ranging from ~0.5 wt.{\%} in “clean wood” to ~15 wt.{\%} in chicken litter. For that reason alone, results presented in this thesis are not limited to the self-gasification concept where methane is the final product, but give valuable information for other biomass gasification processes as well. Subjects such as gasification under pressure, methane formation and the effect of naturally occurring ash in biomass are dealt with in this thesis. The concept is now ready to be studied in an integrated bench-scale unit for further evaluation.",
keywords = "METIS-296480, IR-85988",
author = "Pavlina Nanou",
year = "2013",
month = "5",
day = "17",
doi = "10.3990/1.9789036535434",
language = "English",
isbn = "978-90-365-3543-4",
publisher = "Universiteit Twente",
school = "University of Twente",

}

Biomass gasification for the production of methane. / Nanou, Pavlina.

Enschede : Universiteit Twente, 2013. 173 p.

Research output: ThesisPhD Thesis - Research UT, graduation UTAcademic

TY - THES

T1 - Biomass gasification for the production of methane

AU - Nanou, Pavlina

PY - 2013/5/17

Y1 - 2013/5/17

N2 - Biomass is very promising as a sustainable alternative to fossil resources because it is a renewable source that contains carbon, an essential building block for gaseous and liquid fuels. Methane is the main component of natural gas, which is a fuel used for heating, power generation and transportation. In The Netherlands, the contribution of natural gas to the primary energy consumption is almost 50% (Source: Energy Research Centre of The Netherlands [ECN]) and it is a fuel with a well-developed pipeline distribution network and infrastructure. There are different biomass conversion routes to methane depending on the water content of the biomass feed. The thermochemical conversion route to convert relatively dry biomass into methane is conventionally envisaged in a two-step process: In the first step, biomass is gasified (with heat demand, high T / low P) and in the second step methane is formed (with heat release, low T / high P) in a separate reactor. In this configuration there is no heat integration possible between the two process stages. In this thesis, a new gasification concept is investigated, termed self-gasification, that overcomes, inter alia, the issue of heat integration. The concept entails an intermediate temperature (700-800°C) and pressure (25-35 bar) steam gasifier, where recycled ash components -contained in the biomass itself- serve as potential “catalysts” for char (from biomass pyrolysis) gasification, methane formation, gas conditioning and tar cracking. The focus of the present research lies on process evaluation and study of the influence of biomass ashes on the aforementioned reactions. Ashes are present in different concentrations in targeted biomass feeds for gasification; ranging from ~0.5 wt.% in “clean wood” to ~15 wt.% in chicken litter. For that reason alone, results presented in this thesis are not limited to the self-gasification concept where methane is the final product, but give valuable information for other biomass gasification processes as well. Subjects such as gasification under pressure, methane formation and the effect of naturally occurring ash in biomass are dealt with in this thesis. The concept is now ready to be studied in an integrated bench-scale unit for further evaluation.

AB - Biomass is very promising as a sustainable alternative to fossil resources because it is a renewable source that contains carbon, an essential building block for gaseous and liquid fuels. Methane is the main component of natural gas, which is a fuel used for heating, power generation and transportation. In The Netherlands, the contribution of natural gas to the primary energy consumption is almost 50% (Source: Energy Research Centre of The Netherlands [ECN]) and it is a fuel with a well-developed pipeline distribution network and infrastructure. There are different biomass conversion routes to methane depending on the water content of the biomass feed. The thermochemical conversion route to convert relatively dry biomass into methane is conventionally envisaged in a two-step process: In the first step, biomass is gasified (with heat demand, high T / low P) and in the second step methane is formed (with heat release, low T / high P) in a separate reactor. In this configuration there is no heat integration possible between the two process stages. In this thesis, a new gasification concept is investigated, termed self-gasification, that overcomes, inter alia, the issue of heat integration. The concept entails an intermediate temperature (700-800°C) and pressure (25-35 bar) steam gasifier, where recycled ash components -contained in the biomass itself- serve as potential “catalysts” for char (from biomass pyrolysis) gasification, methane formation, gas conditioning and tar cracking. The focus of the present research lies on process evaluation and study of the influence of biomass ashes on the aforementioned reactions. Ashes are present in different concentrations in targeted biomass feeds for gasification; ranging from ~0.5 wt.% in “clean wood” to ~15 wt.% in chicken litter. For that reason alone, results presented in this thesis are not limited to the self-gasification concept where methane is the final product, but give valuable information for other biomass gasification processes as well. Subjects such as gasification under pressure, methane formation and the effect of naturally occurring ash in biomass are dealt with in this thesis. The concept is now ready to be studied in an integrated bench-scale unit for further evaluation.

KW - METIS-296480

KW - IR-85988

U2 - 10.3990/1.9789036535434

DO - 10.3990/1.9789036535434

M3 - PhD Thesis - Research UT, graduation UT

SN - 978-90-365-3543-4

PB - Universiteit Twente

CY - Enschede

ER -