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  • 1.
    Kreitzberg, Thobias
    et al.
    Rhein Westfal TH Aachen, Inst Heat & Mass Transfer, Aachen, Germany.
    Phounglamcheik, Aekjuthon
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Haugen, Nils Erland L.
    INTEF Energy Res, Dept Thermal Energy, Trondheim, Norway.
    Kneer, Reinhold
    Rhein Westfal TH Aachen, Inst Heat & Mass Transfer, Aachen, Germany.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    A Shortcut Method to Predict Particle Size Changes during Char Combustion and Gasification under regime II Conditions2019Ingår i: Combustion Science and Technology, ISSN 0010-2202, E-ISSN 1563-521XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    In most industrial applications, combustion and gasification of char progresses under regime II conditions. Unlike in other regimes, both particle size and density change simultaneously in regime II due to non-uniform consumption of carbon inside the particles. In this work, mathematical predictions of diameter changes in regime II were made by a one-dimensional simulation tool, where transient species balances are resolved locally inside the particle. This simulation is computationally expensive and usually not appropriate for the implementation in comprehensive CFD simulations of combustion or gasification processes. To overcome this restraint, an alternative shortcut method with affordable computation time has been developed and validated against the detailed model. This method allows the calculation of diameter changes during combustion and gasification from precalculated effectiveness factors. Additionally, the change of particle size has been investigated experimentally in a single particle converter setup. Therein, particles are fixed on a sample holder placed in the hot flue gas of a flat flame burner. Size and temperature trends are optically assessed by a 3CCD camera.

  • 2.
    Phounglamcheik, Aekjuthon
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Biocarbon for fossil coal replacement2018Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This research aims to provide a full view of knowledge in charcoal production for fossil coal replacement. Charcoal from biomass is a promising material to replace fossil coal, which is using as heating source or reactant in the industrial sector. Nowadays, charcoal with quality comparable to fossil coal is produced by high-temperature pyrolysis, but efficiency of the production is relatively low due to the trade-off between charcoal property and yield by pyrolysis temperature. Increasing charcoal yield by means of secondary char formation in pyrolysis of large wood particles is the primary method considering in this work. This research has explored increasing efficiency of charcoal production by bio-oil recycling and CO2 purging. These proposed techniques significantly increase concentration and extend residence time of volatiles inside particle of woodchip resulting extra charcoal. Characterization of charcoals implies negligible effect of these methods on charcoal properties such as elemental composition, heating value, morphological structure, and chemical structure. Besides, reactivity of charcoal slightly increased when these methods were applied. A numerical model of pyrolysis in a rotary kiln reactor has been developed to study the effect of design parameters and conditions in reactor scale. The simulation results showed fair prediction of temperature profiles and products distribution along the reactor length. Nonetheless, to deliver full knowledge in charcoal production, further works are planned to be done at the end of this doctoral research.

  • 3.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Change in size and density of a biomass char during heterogeneous reactions2018Konferensbidrag (Refereegranskat)
  • 4.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wang, Liang
    SINTEF Energy Research .
    Romar, Henrik
    University of Oulu, Research Unit of Applied Chemistry.
    Broström, Markus
    Umeå University, Department of Applied Physics and Electronics.
    Ramser, Kerstin
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Skreiberg, Øyvind
    SINTEF Energy Research .
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Effects of pyrolysis oil recycling and reaction gas atmosphere on the physical properties and reactivity of charcoal from wood2018Konferensbidrag (Refereegranskat)
  • 5.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wretborn, Tobias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Increasing efficiency of charcoal production with bio-oil recycling2018Ingår i: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, nr 9, s. 9650-9658Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Charcoal from biomass is a promising alternative for fossil coal. Although its quality increases at high pyrolysis temperature, charcoal yield decreases, meaning lower economic performances of charcoal production processes. This work aims at demonstrating potential methods to increase charcoal yield while keeping its quality at satisfying levels. We suggested the recycling of bio-oil from pyrolysis process as a primary measure. In addition, we also investigated in detail the consequence of utilizing CO2 instead of N2 as reaction media under practical conditions (i.e. thick particles). An experimental investigation was carried out in a macro-thermogravimetric (macro-TG) reactor. Sample (woodchips, bio-oil, and woodchips embedded with bio-oil) was exposed to the reaction temperature either instantaneously (isothermal condition) or by slow heating (slow pyrolysis) in controlled gas flows of N2 and CO2. The results showed that char yield increases with the bio-oil recycling on wood chips at all pyrolysis temperatures (300–700 °C). By 20% of bio-oil embedding on wood chips, charcoal yield increased by 18.3% on average. The increase of charcoal yield was not only because of the increase in reactants, but also due to the synergetic effect between bio-oil and wood chips upon physical contact. Bio-oil recycling had negligible effects on the property of charcoal, such as carbon content and heating value. Although CO2 did not affect primary pyrolysis, it had effects on mass transfer processes. As a result, significantly higher char yield was obtained from pyrolysis in CO2 than in N2 by ensuring a good contact of volatiles and solid surface (i.e. usage of thick particles and slow heating). This study suggests that we can achieve high charcoal yield while maintaining the similar charcoal property by bio-oil recycling, CO2 purging, use of thick particles, and slow heating.

  • 6.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Pitchot, Romain
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Andefors, Alf
    Future Eco North Sweden AB.
    Norberg, Niclas
    Future Eco North Sweden AB.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Production of metallurgical charcoal from biomass pyrolysis: pilot-scale experiment2018Konferensbidrag (Refereegranskat)
  • 7.
    Toloue Farrokh, Najibeh
    et al.
    Process Metallurgy Research Unit, University of Oulu, P.O. Box 4300, FI-90014, Oulu, Finland.
    Suopajärvi, Hannu
    Process Metallurgy Research Unit, University of Oulu, P.O. Box 4300, FI-90014, Oulu, Finland.
    Mattila, Olli
    Process Metallurgy Research Unit, University of Oulu, P.O. Box 4300, FI-90014, Oulu, Finland.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Phounglamcheik, Aekjuthon
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Romar, Henrik
    Research Unit of Sustainable Chemistry, University of Oulu, P.O. Box 3000, FI-90014, Oulu,.
    Sulasalmi, Petri
    Process Metallurgy Research Unit, University of Oulu, P.O. Box 4300, FI-90014, Oulu.
    Fabritius, Timo
    Process Metallurgy Research Unit, University of Oulu, P.O. Box 4300, FI-90014, Oulu.
    Slow pyrolysis of by-product lignin from wood-based ethanol production: A detailed analysis of the produced chars2018Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 164, s. 112-123Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Slow pyrolysis as a method of producing a high-quality energy carrier from lignin recovered from wood-based ethanol production has not been studied for co-firing or blast furnace (BF) applications up to now. This paper investigates fuel characteristics, grindability, moisture uptake and the flow properties of lignin chars derived from the slow pyrolysis of lignin at temperatures of 300, 500 and 650 °C (L300, L500 and L650 samples respectively) at a heating rate of 5 °C min-1. The lignin chars revealed a high mass and energy yield in the range of 39-73% and 53-89% respectively. Pyrolysis at 500 °C or higher, yielded lignin chars with low H/C and O/C ratios suitable for BF injection. Furthermore, the hydrophobicity of lignin was improved tremendously after pyrolysis. Pyrolysis at high temperatures increased the sphericity of the lignin char particles and caused some agglomeration in L650. Large and less spherical particles were found to be a reason for high permeability, compressibility and cohesion of L300 in contrast to L500 and L650. L300 and L500 chars demonstrated high combustibility with low ignition and burnout temperatures. Also, rheometric analysis showed that L500 has the best flow properties including low aeration energy and high flow function.

  • 8.
    Suopajärvi, Hannu
    et al.
    Process Metallurgy Research Unit, University of Oulu.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Mousa, Elsayed
    Swerea MEFOS, Process Integration Department.
    Hedayati, Ali
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Romar, Henrik
    Research Unit of Sustainable Chemistry, University of Oulu.
    Kemppainen, Antti
    Process Metallurgy Research Unit, University of Oulu.
    Wang, Chuan
    Swerea MEFOS, Process Integration Department.
    Phounglamcheik, Aekjuthon
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Tuomikoski, Sari
    Research Unit of Sustainable Chemistry, University of Oulu.
    Norberg, Nicklas
    Future Eco North Sweden AB.
    Andefors, Alf
    Future Eco North Sweden AB.
    Öhman, Marcus
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lassi, Ulla
    Research Unit of Sustainable Chemistry, University of Oulu.
    Fabritius, Timo
    Process Metallurgy Research Unit, University of Oulu.
    Use of biomass in integrated steelmaking: Status quo, future needs and comparison to other low-CO2 steel production technologies2018Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 213, s. 384-407Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper provides a fundamental and critical review of biomass application as a reducing agent and fuel in integrated steelmaking. The basis for the review is derived from the current process and product quality requirements that also biomass-derived fuels should fulfill. The availability and characteristics of different sources of biomass are discussed and suitable pretreatment technologies for their upgrading are evaluated. The existing literature concerning biomass application in bio-coke making, blast furnace injection, iron ore sintering and production of carbon composite agglomerates is reviewed and research gaps filled by providing insights and recommendations to the unresolved challenges. Several possibilities to integrate the production of biomass-based reducing agents with existing industrial infrastructures to lower the cost and increase the total efficiency are given. A comparison of technical challenges and CO2 emission reduction potential between biomass-based steelmaking and other emerging technologies to produce low-CO2 steel is made.

  • 9.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wretborn, Tobias
    Luleå tekniska universitet.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Biomass pyrolysis with bio-oil recycle to increase energy recovery2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    This study aims at increasing char yield by recycling bio-oil without negative impact on char qualities, i.e. carbon content and heating value. Pyrolysis experiments on spruce and birch chips were carried in a macro-thermogravimetric analyzer. To examine the effect of bio-oil recycle, dried raw woodchips, pure bio-oil, and woodchips impregnated with bio-oil (10, 20 and 25% on mass basis) were compared. The experiments were carried out by introducing sample into the reaction zone with the flow of N2 and at the temperature range of 300 to 600 ˚C. Pyrolysis of the bio-oil impregnated woodchip gave higher char yield than the pyrolysis of raw woodchip. By the 20% (m/m) bio-oil impregnation, char yield increased by 18.9% (spruce) and 19.1% (birch) on average from the raw woodchip pyrolysis. In addition, the char yield from bio-oil impregnated woodchips was higher than the interpolated char yield of raw woodchips and bio-oil, indicating that synergy effect exists by bio-oil impregnation compared with mere recycling of bio-oil. However, high heating rate corresponded to high temperature pyrolysis, i.e. above 400 ˚C, created cavities and breakages on woodchips, which minimized the secondary reaction. Neither carbon content nor heating value of char was influenced by bio-oil impregnation. Energy yield also showed improvement by increasing bio-oil recycling ratio. For example, energy yield of char from woodchips at the temperature of 340 ˚C increased from 48.4% with raw woodchips to 64.5% by woodchips with 25% of bio-oil impregnation.

  • 10.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wretborn, Tobias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Biomass pyrolysis with bio-oil recycle to increase energy recovery in biochar2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    ABSTRACT: This study aims at increasing char yield by recycling bio-oil without negative impact on char qualities, i.e. carbon content and heating value. Pyrolysis experiments on spruce and birch chips were carried in a macro-thermogravimetric analyzer. To examine the effect of bio-oil recycle, dried raw woodchips, pure bio-oil, and woodchips impregnated with bio-oil (10, 20 and 25% on mass basis) were compared. The experiments were carried out by introducing sample into the reaction zone with the flow of N2 and at the temperature range of 300 to 600 ˚C. Pyrolysis of the bio-oil impregnated woodchip gave higher char yield than the pyrolysis of raw woodchip. By the 20% (m/m) bio-oil impregnation, char yield increased by 18.9% (spruce) and 19.1% (birch) on average from the raw woodchip pyrolysis. In addition, the char yield from bio-oil impregnated woodchips was higher than the interpolated char yield of raw woodchips and bio-oil, indicating that synergy effect exists by bio-oil impregnation compared with mere recycling of bio-oil. However, high heating rate corresponded to high temperature pyrolysis, i.e. above 400 ˚C, created cavities and breakages on woodchips, which minimized the secondary reaction. Neither carbon content nor heating value of char was influenced by bio-oil impregnation. Energy yield also showed improvement by increasing bio-oil recycling ratio. For example, energy yield of char from woodchips at the temperature of 340 ˚C increased from 48.4% with raw woodchips to 64.5% by woodchips with 25% of bio-oil impregnation.

  • 11.
    Babler, Matthaus U.
    et al.
    Department Chemical Engineering and Technology, KTH Royal Institute of Technology.
    Phounglamcheik, Aekjuthon
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Amovic, Marko
    Cortus Energy AB.
    Ljunggren, Rolf
    Cortus Energy AB.
    Engvall, Klas
    Department Chemical Engineering and Technology, KTH Royal Institute of Technology.
    Modeling and pilot plant runs of slow biomass pyrolysis in a rotary kiln2017Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 207, s. 123-133Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pyrolysis of biomass in a rotary kiln finds application both as an intermediate step in multistage gasification as well as a process on its own for the production of biochar. In this work, a numerical model for pyrolysis of lignocellulosic biomass in a rotary kiln is developed. The model is based on a set of conservation equations for mass and energy, combined with independent submodels for the pyrolysis reaction, heat transfer, and granular flow inside the kiln. The pyrolysis reaction is described by a two-step mechanism where biomass decays into gas, char, and tar that subsequently undergo further reactions; the heat transfer model accounts for conduction, convection and radiation inside the kiln; and the granular flow model is described by the well known Saeman model. The model is compared to experimental data obtained from a pilot scale rotary kiln pyrolyzer. In total 9 pilot plant trials at different feed flow rate and different heat supply were run. For moderate heat supplies we found good agreement between the model and the experiments while deviations were seen at high heat supply. Using the model to simulate various operation conditions reveals a strong interplay between heat transfer and granular flow which both are controlled by the kiln rotation speed. Also, the model indicates the importance of heat losses and lays the foundation for scale up calculations and process optimization.

  • 12.
    Phounglamcheik, Aekjuthon
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Babler, Matthaus U.
    Department Chemical Engineering and Technology, KTH Royal Institute of Technology.
    Donaj, Pawel
    Cortus Energy.
    Amovic, Marko
    Cortus Energy.
    Ljunggren, Rolf
    Cortus Energy.
    Engvall, Klas
    Department Chemical Engineering and Technology, KTH Royal Institute of Technology.
    Pyrolysis of Wood in a Rotary Kiln Pyrolyzer: Modeling and Pilot Plant Trials2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 908-913Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gasification is a key technology for the utilization of biomass as an energy carrier. The WoodRoll process developed by Cortus Energy is a multistage gasification process where drying, pyrolysis and gasification are conducted in separate units. A central role is thereby given to the pyrolysis step which provides the gas to heat the entire process. In the WoodRoll process pyrolysis is run in an indirectly heated rotary kiln. In this work we study pyrolysis in a rotary kiln by means of numerical simulations and by evaluating pilot plant data obtained from a 500 kW pilot. The simulations indicate the importance of the heat transfer to the solid bed and the exothermic pyrolysis reactions that occur in the late stage of the pyrolysis process. The latter can cause an overshoot of the solid bed temperature. Evaluation of the pilot plant data shows the robustness of the process, expressed in good reproducible and stable operation.

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