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Mesfun, S., Lundgren, J., Toffolo, A., Lindbergh, G., Lagergren, C. & Engvall, K. (2019). Integration of an electrolysis unit for producer gas conditioning in a bio-synthetic natural gas plant. Journal of energy resources technology, 141(1), Article ID 012002.
Open this publication in new window or tab >>Integration of an electrolysis unit for producer gas conditioning in a bio-synthetic natural gas plant
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2019 (English)In: Journal of energy resources technology, ISSN 0195-0738, E-ISSN 1528-8994, Vol. 141, no 1, article id 012002Article in journal (Refereed) Published
Abstract [en]

Producer gas from biomass gasification contains impurities like tars, particles, alkali salts, and sulfur/nitrogen compounds. As a result, a number of process steps are required to condition the producer gas before utilization as a syngas and further upgrading to final chemicals and fuels. Here, we study the concept of using molten carbonate electrolysis cells (MCEC) both to clean and to condition the composition of a raw syngas stream, from biomass gasification, for further upgrading into synthetic natural gas (SNG). A mathematical MCEC model is used to analyze the impact of operational parameters, such as current density, pressure and temperature, on the quality and amount of syngas produced. Internal rate of return (IRR) is evaluated as an economic indicator of the processes considered. Results indicate that, depending on process configuration, the production of SNG can be boosted by approximately 50-60% without the need of an additional carbon source, i.e., for the same biomass input as in standalone operation of the GoBi-Gas plant. Copyright

Place, publisher, year, edition, pages
The American Society of Mechanical Engineers (ASME), 2019
National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-70732 (URN)10.1115/1.4040942 (DOI)000452421900004 ()2-s2.0-85052065806 (Scopus ID)
Note

Validerad;2018;Nivå 2;2018-09-03 (andbra)

Available from: 2018-09-03 Created: 2018-09-03 Last updated: 2019-02-13Bibliographically approved
Mesfun, S., Lundgren, J., Toffolo, A., Lindbergh, G., Lagergren, C. & Engvall, K. (2017). Integration of an electrolysis unit for producer gas conditioning in a bio-SNG plant. In: 30th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, ECOS 2017: . Paper presented at 30th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, ECOS 2017, San Diego, United States, 2-6 July 2017. International Measurement Confederation (IMEKO)
Open this publication in new window or tab >>Integration of an electrolysis unit for producer gas conditioning in a bio-SNG plant
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2017 (English)In: 30th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, ECOS 2017, International Measurement Confederation (IMEKO) , 2017Conference paper, Published paper (Refereed)
Abstract [en]

Producer gas from biomass gasification contains impurities like tars, particles, alkali salts and sulfur/nitrogen compounds. As a result a number of process steps are required to condition the producer gas before utilization as a syngas and further upgrading to final chemicals and fuels. Here, we study the concept of using molten carbonate electrolysis cells (MCEC) both to clean and to condition the composition of a raw syngas stream, from biomass gasification, for further upgrading into SNG. A mathematical MCEC model is used to analyze the impact of operational parameters, such as current density, pressure and temperature, on the quality and amount of tailored syngas produced. Investment opportunity is evaluated as an economic indicator of the processes considered. Results indicate that the production of SNG can be boosted by approximately 50% without the need of an additional carbon source, i.e. for the same biomass input as in standalone operation of the GoBiGas plant.

Place, publisher, year, edition, pages
International Measurement Confederation (IMEKO), 2017
National Category
Energy Engineering
Research subject
Energy Engineering; Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-69897 (URN)
Conference
30th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, ECOS 2017, San Diego, United States, 2-6 July 2017
Available from: 2018-06-26 Created: 2018-06-26 Last updated: 2018-06-26Bibliographically approved
Mesfun, S., Sanchez, D. L., Leduc, S., Wetterlund, E., Lundgren, J., Biberacher, M. & Kraxner, F. (2017). Power-to-gas and power-to-liquid for managing renewable electricity intermittency in the Alpine Region. Renewable energy, 107, 361-372
Open this publication in new window or tab >>Power-to-gas and power-to-liquid for managing renewable electricity intermittency in the Alpine Region
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2017 (English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 107, p. 361-372Article in journal (Refereed) Published
Abstract [en]

Large-scale deployment of renewable energy sources (RES) plays a central role in reducing CO2 emissions from energy supply systems, but intermittency from solar and wind technologies presents integration challenges. High temperature co-electrolysis of steam and CO2 in power-to-gas (PtG) and power-to-liquid (PtL) configurations could utilize excess intermittent electricity by converting it into chemical fuels. These can then be directly consumed in other sectors, such as transportation and heating, or used as power storage. Here, we investigate the impact of carbon policy and fossil fuel prices on the economic and engineering potential of PtG and PtL systems as storage for intermittent renewable electricity and as a source of low-carbon heating and transportation energy in the Alpine region. We employ a spatially and temporally explicit optimization approach of RES, PtG, PtL and fossil technologies in the electricity, heating, and transportation sectors, using the BeWhere model. Results indicate that large-scale deployment of PtG and PtL technologies for producing chemical fuels from excess intermittent electricity is feasible, particularly when incentivized by carbon prices. Depending on carbon and fossil fuel price, 0.15−15 million tonnes/year of captured CO2 can be used in the synthesis of the chemical fuels, displacing up to 11% of current fossil fuel use in transportation. By providing a physical link between the electricity, transportation, and heating sectors, PtG and PtL technologies can enable greater integration of RES into the energy supply chain globally.

Place, publisher, year, edition, pages
Elsevier, 2017
National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-61957 (URN)10.1016/j.renene.2017.02.020 (DOI)000396946900032 ()2-s2.0-85013158197 (Scopus ID)
Note

Validerad; 2017; Nivå 2; 2017-03-01 (andbra)

Available from: 2017-02-13 Created: 2017-02-13 Last updated: 2018-09-13Bibliographically approved
Mesfun, S., Anderson, J.-O., Umeki, K. & Toffolo, A. (2016). Integrated SNG Production in a Typical Nordic Sawmill (ed.). Paper presented at . Energies, 9(5), Article ID 333..
Open this publication in new window or tab >>Integrated SNG Production in a Typical Nordic Sawmill
2016 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 5, article id 333.Article in journal (Refereed) Published
Abstract [en]

Advanced biomass-based motor fuels and chemicals are becoming increasingly important to replace fossil energy sources within the coming decades. It is likely that the new biorefineries will evolve mainly from existing forest industry sites, as they already have the required biomass handling infrastructure in place. The main objective of this work is to assess the potential for increasing the profit margin from sawmill byproducts by integrating innovative downstream processes. The focus is on the techno-economic evaluation of an integrated site for biomass-based synthetic natural gas (bio-SNG) production. The option of using the syngas in a biomass-integrated gasification combined cycle (b-IGCC) for the production of electricity (instead of SNG) is also considered for comparison. The process flowsheets that are used to analyze the energy and material balances are modelled in MATLAB and Simulink. A mathematical process integration model of a typical Nordic sawmill is used to analyze the effects on the energy flows in the overall site, as well as to evaluate the site economics. Different plant sizes have been considered in order to assess the economy-of-scale effect. The technical data required as input are collected from the literature and, in some cases, from experiments. The investment cost is evaluated on the basis of conducted studies, third party supplier budget quotations and in-house database information. This paper presents complete material and energy balances of the considered processes and the resulting process economics. Results show that in order for the integrated SNG production to be favored, depending on the sawmill size, a biofuel subsidy in the order of 28–52 €/MWh SNG is required.

National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-11602 (URN)10.3390/en9050333 (DOI)000377263400025 ()2-s2.0-84968807206 (Scopus ID)a9cad9b4-9937-43e1-b40d-14eaef443c81 (Local ID)a9cad9b4-9937-43e1-b40d-14eaef443c81 (Archive number)a9cad9b4-9937-43e1-b40d-14eaef443c81 (OAI)
Note
Validerad; 2016; Nivå 2; 20160701 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Mesfun, S. (2016). Process integration to increase woody biomass utilization for energy purposes (ed.). (Doctoral dissertation). Paper presented at . Luleå tekniska universitet
Open this publication in new window or tab >>Process integration to increase woody biomass utilization for energy purposes
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Woody biomass is an abundant renewable energy resource in Sweden, and the Swedish government has been promoting research and development programs for the exploitation of this resource as a mean to meet the targets on the reduction of the carbon dioxide emissions from the industrial, energy and transportation sectors. This thesis aims at expanding the knowledge on the efficient utilization of the available woody biomass, so that a larger amount of this renewable resource can be used for energy purposes. The thesis presents a collection of studies following the main two policies that have been identified for the reduction of carbon dioxide emission, i.e. the implementation of measures improving energy conservation and efficiency and a deep decarbonization of the energy sector. Process integration and optimization techniques are applied to forest industry sites in order to improve the resource and energy efficiency, the benefits of the integrated design configurations being evaluated by both technical and economic analyses. The integration of woody biomass with intermittent renewable energy sources is also studied in order to enable a large share of non-fossil sources in the energy mix.The results of the investigations show a significant potential for improving biomass resource utilization in the forest industry sites strictly from the energetic point of view. Optimizing the process integration in sites including Kraft pulp and paper mills and/or sawmills and a dedicated common CHP system can lead to a much greater power generation for the same input biomass and for the same production volume, or to large amounts of excess heat to be used in nearby processes or district heating, or even to the re-routing of part of the input biomass to other conversion processes (e.g. lignin separation and hemicellulose fermentation to produce biofuels). The operational profit of the site is consequently increased, but, when the investment costs are considered, some form of subsidies to the “green” byproducts are usually still required to make the integrated design configurations economically viable. The integration of woody biomass with intermittent renewable energy sources can result in an increased efficiency of hybrid power generation plants (e.g. with concentrated solar thermal collectors), and on a large scale it could facilitate the decarbonization of the energy sector with the fundamental contribution from power-to-X technologies in order to produce chemical fuels from the excess intermittent electricity. These technologies would be clearly incentivized by a carbon tax, but the benefit deriving from the large volumes of captured CO2 that are required for the synthesis of chemical fuels through co-electrolysis should also be taken into account. Keywords: Forest industry, process integration, pinch analysis, HEATSEP method, optimization, CHP system, techno-economic, biorefinery, intermittent renewables.

Place, publisher, year, edition, pages
Luleå tekniska universitet, 2016
Series
Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, ISSN 1402-1544
National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-16829 (URN)034f0cc4-c9b0-49b0-97bd-c7711b9c9c67 (Local ID)978-91-7583-599-0 (ISBN)978-91-7583-600-3 (ISBN)034f0cc4-c9b0-49b0-97bd-c7711b9c9c67 (Archive number)034f0cc4-c9b0-49b0-97bd-c7711b9c9c67 (OAI)
Note

Godkänd; 2016; 20160412 (senmes); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Sennai Mesfun Ämne: Energiteknik /Energy Engineering Avhandling: Process Integration to Increase Woody Biomass Utilization for Energy Purposes Opponent: Associate professor Francesco Fantozzi, Department of Engineering & Biomass Research Center, University of Perugia, Perugia, Italien. Ordförande: Professor Andrea Toffolo, Avd för energivetenskap, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet, Luleå. Tid: Torsdag 9 juni, 2016 kl 14.00 Plats: E632, Luleå tekniska universitet

Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2017-11-24Bibliographically approved
Mesfun, S., Andersson, J. O., Umeki, K. & Toffolo, A. (2015). Integrated SNG production in a typical Nordic sawmill (ed.). In: (Ed.), (Ed.), ECOS 2015: 28th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems. Paper presented at International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems : 29/06/2015 - 03/07/2015. : International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems
Open this publication in new window or tab >>Integrated SNG production in a typical Nordic sawmill
2015 (English)In: ECOS 2015: 28th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems , 2015Conference paper, Published paper (Refereed)
Abstract [en]

Advanced biomass based motor fuels and chemicals are becoming increasingly important to replace fossil energy sources within the coming decades. It is likely that the new biorefineries will evolve mainly from existing forest industry sites as they already have the required biomass handling infrastructure in place. The main objective of this work is to assess the potential for increasing the profit margin from sawmill byproducts by integrating innovative downstream processes. The focus is on the techno-economic evaluation of an integrated site for bio-SNG production. The option of using the syngas in a b-IGCC for the production of electricity (instead of SNG) is also considered for comparison. The process flowsheets that are used to analyse the energy and material balances are modelled in MATLAB and Simulink. A mathematical process integration model of a typical Nordic sawmill is used to analyse the effects on the energy flows in the overall site as well as to evaluate the site economics. Different plant sizes have been considered in order to assess the economy-of-scale effect. The technical data required as input are collected from the literature and, in some cases, from experiments. The investment cost is evaluated on the basis of conducted studies, third party supplier budget quotations and in-house database information. This paper presents complete material and energy balances of the considered processes and the resulting process economics.

Place, publisher, year, edition, pages
International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, 2015
National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-34877 (URN)84978786027 (Scopus ID)9312a000-1200-4530-bec8-03eddbaab15f (Local ID)9782955553909 (ISBN)9312a000-1200-4530-bec8-03eddbaab15f (Archive number)9312a000-1200-4530-bec8-03eddbaab15f (OAI)
Conference
International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems : 29/06/2015 - 03/07/2015
Note
Godkänd; 2015; 20160817 (andbra)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Mesfun, S. & Toffolo, A. (2015). Integrating the processes of a Kraft pulp and paper mill and its supply chain (ed.). Paper presented at International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems : 15/06/2014 - 19/06/2014. Energy Conversion and Management, 103, 300-310
Open this publication in new window or tab >>Integrating the processes of a Kraft pulp and paper mill and its supply chain
2015 (English)In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 103, p. 300-310Article in journal (Refereed) Published
Abstract [en]

This paper investigates the possibility of combining different forest industries (a pulp and paper mill, its supply chain, and a wood-pellet plant) into an integrated industrial site in which they share a common heat and power utility. Advanced process integration and optimization techniques are used to study the site from both material and energy viewpoints. An existing pulp and paper mill is used as the site core plant and its pulp and paper production rates are kept fixed as they are in reality, while the other material flow links among the plants are based on the current industrial situation in Sweden. Different scenarios are evaluated in order to reflect the two main objectives that can be pursued (increased electricity production or biomass resource saving) and the two technologies that can be considered for the shared CHP system (boilers and product gas fired gas turbines). The corresponding non-integrated (standalone) configurations are compared to these scenarios to quantify the potential benefits of the integration. Investment opportunity is also calculated for the considered scenarios as an indicator of the economic convenience

National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-11800 (URN)10.1016/j.enconman.2015.06.063 (DOI)000359873300031 ()2-s2.0-84935507224 (Scopus ID)acf77323-f1e5-424d-b3c0-767432015c1d (Local ID)acf77323-f1e5-424d-b3c0-767432015c1d (Archive number)acf77323-f1e5-424d-b3c0-767432015c1d (OAI)
Conference
International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems : 15/06/2014 - 19/06/2014
Note
Validerad; 2015; Nivå 2; 20150715 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Tanaka, Y., Mesfun, S., Umeki, K., Toffolo, A., Tamura, Y. & Yoshikawa, K. (2015). Thermodynamic performance of a hybrid power generation system using biomass gasification and concentrated solar thermal processes (ed.). Paper presented at . Applied Energy, 160, 664-672
Open this publication in new window or tab >>Thermodynamic performance of a hybrid power generation system using biomass gasification and concentrated solar thermal processes
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2015 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 160, p. 664-672Article in journal (Refereed) Published
Abstract [en]

This paper describes the investigation of a hybrid power production system from biomass and solar energy. This paper suggests integration through heat exchanger network as a useful approach to obtain the synergy between biomass and solar. Biomass is first gasified in a bubbling fluidized bed (BFB) gasifier, and then syngas is used in a gas turbine. Excess heat exists in this sub-system and concentrated solar thermal process (CSTP) while there is a demand of steam for generating gasifying agent. Steam Rankine cycle exploits the heat created by these thermal streams to generate power while satisfying the steam demands. Thermodynamic performance was analyzed by process modelling with a semi-kinetic model of BFB gasifier and pinch analyses. The composition and temperature of gasifying agent showed some effect on the overall efficiency of the system. Higher overall efficiency of the system was achieved at higher temperature and higher O2 fraction in the O2-steam mixture as gasifying agent. The increase in thermal input from CSTP had positive effect on overall efficiency of the hybrid system until thermal input from CSTP becomes dominant against thermal stream related to the gasifier and the gas turbine.

National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-7381 (URN)10.1016/j.apenergy.2015.05.084 (DOI)000364890700062 ()2-s2.0-84946017400 (Scopus ID)5c15e41c-5a03-49f0-b32b-c9320a193e53 (Local ID)5c15e41c-5a03-49f0-b32b-c9320a193e53 (Archive number)5c15e41c-5a03-49f0-b32b-c9320a193e53 (OAI)
Note
Validerad; 2016; Nivå 2; 20150615 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Mesfun, S., Lundgren, J., Grip, C.-E., Toffolo, A., Kudahettige-Nilsson, R. & Rova, U. (2014). Black liquor fractionation for biofuels production: A techno-economic assessment (ed.). Paper presented at . Bioresource Technology, 166, 508-517
Open this publication in new window or tab >>Black liquor fractionation for biofuels production: A techno-economic assessment
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2014 (English)In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 166, p. 508-517Article in journal (Refereed) Published
Abstract [en]

The hemicelluloses fraction of black liquor is an underutilized resource in many chemical pulp mills. It is possible to extract and separate the lignin and hemicelluloses from the black liquor and use the hemicelluloses for biochemical conversion into biofuels and chemicals. Precipitation of the lignin from the black liquor would consequently decrease the thermal load on the recovery boiler, which is often referred to as a bottleneck for increased pulp production. The objective of this work is to techno-economically evaluate the production of sodium-free lignin as a solid fuel and butanol to be used as fossil gasoline replacement by fractionating black liquor. The hydrolysis and fermentation processes are modeled in Aspen Plus to analyze energy and material balances as well as to evaluate the plant economics. A mathematical model of an existing pulp and paper mill is used to analyze the effects on the energy performance of the mill subprocesses.

National Category
Energy Engineering Bioprocess Technology
Research subject
Energy Engineering; Biochemical Process Engineering
Identifiers
urn:nbn:se:ltu:diva-15033 (URN)10.1016/j.biortech.2014.05.062 (DOI)000338711100066 ()24950095 (PubMedID)2-s2.0-84902440727 (Scopus ID)e7e17be6-d447-4162-bba8-f0556f074a69 (Local ID)e7e17be6-d447-4162-bba8-f0556f074a69 (Archive number)e7e17be6-d447-4162-bba8-f0556f074a69 (OAI)
Note
Validerad; 2014; 20140603 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Mesfun, S. (2014). Design of integrated industrial sites based on Kraft pulp and paper mills (ed.). (Licentiate dissertation). Paper presented at .
Open this publication in new window or tab >>Design of integrated industrial sites based on Kraft pulp and paper mills
2014 (English)Licentiate thesis, comprehensive summary (Other academic)
Series
Licentiate thesis / Luleå University of Technology, ISSN 1402-1757
National Category
Energy Engineering
Research subject
Energy Engineering
Identifiers
urn:nbn:se:ltu:diva-26544 (URN)ec8f3c88-64fa-4e66-97d8-1353c27fb48f (Local ID)978-91-7439-894-6 (ISBN)978-91-7439-895-3 (ISBN)ec8f3c88-64fa-4e66-97d8-1353c27fb48f (Archive number)ec8f3c88-64fa-4e66-97d8-1353c27fb48f (OAI)
Note
Godkänd; 2014; 20140414 (senmes); Nedanstående person kommer att hålla licentiatseminarium för avläggande av teknologie licentiatexamen. Namn: Sennai Mesfun Ämne: Energiteknik/Energy Engineering Uppsats: Design of Integrated Industrial Sites Based on Kraft Pulp and Paper Mills Examinator: Professor Andrea Toffolo, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Diskutant: Assistant Professor Karin Pettersson, Institutionen för energi och miljö, Chalmers tekniska högskola, Göteborg Tid: Tisdag den 20 maj 2014 kl 14.00 Plats: E632, Luleå tekniska universitetAvailable from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-24Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-4909-6643

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