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  • 1. Trubetskaya, Anna
    Fast pyrolysis of biomass at high temperatures2016Doctoral thesis, monograph (Other academic)
  • 2.
    Trubetskaya, Anna
    et al.
    Department of Chemical and Biochemical Engi neering, Technical Univ ersity of Denmark.
    Beckmann, Gert
    Retsch Technology GmbH.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    A way of a single biomass particle shape characterization in a CFD model2014Conference paper (Refereed)
  • 3.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Beckmann, Gert
    Retsch Technology GmbH.
    Wadenbäck, Johan
    Amager power plant, HOFOR A/S.
    Holm, Jens Kai
    DONG Energy Thermal Power A/S.
    Velaga, Sitaram
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Weber, Roman
    Institute of Energy Processes Engineering and Fuel Technology, Clausthal University of Technology.
    One way of representing the size and shape of biomass particles in combustion modeling2017In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 206, p. 675-683Article, book review (Refereed)
    Abstract [en]

    This study aims to provide a geometrical description of biomass particles that can be used in combustion models. The particle size of wood and herbaceous biomass was compared using light microscope, 2D dynamic imaging, laser diffraction, sieve analysis and focused beam reflectance measurement. The results from light microscope and 2D dynamic imaging analysis were compared and it showed that the data on particle width, measured by these two techniques, were identical. Indeed, 2D dynamic imaging was found to be the most convenient particle characterization method, providing information on both the shape and the external surface area. Importantly, a way to quantify all three dimensions of biomass particles has been established. It was recommended to represent a biomass particle in combustion models as an infinite cylinder with the volume-to-surface ratio (V/A) measured using 2D dynamic imaging.

  • 4.
    Trubetskaya, Anna
    et al.
    Thermochemical Energy Conversion Laboratory , Umeå University.
    Broström, Markus
    Thermochemical Energy Conversion Laboratory (TEC-Lab), Department of Applied Physics and Electronics, Umeå University.
    Kling, Jens
    Center for Electron Nanoscopy , Technical University of Denmark.
    Brown, Avery
    Chemical Engineering Department, Worcester Polytechnic Institute.
    Tompsett, Geoffrey
    Chemical Engineering Department, Worcester Polytechnic Institute.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Effects of Lignocellulosic Compounds on the Yield, Nanostructure and Reactivity of Soot from Fast Pyrolysis at High Temperatures2017Conference paper (Other academic)
    Abstract [en]

    Gasification offers the utilization of biomass to a wide variety of applications such as heat, electricity, chemicals and transport fuels in an efficient and sustainable manner. High soot yields in the high-temperature entrained flow gasification lead to intensive gas cleaning and can cause a possible plant shut down. The reduction of soot formation increases the overall production system efficiency and improves the economic feasibility and reliability of the gasification plant. The aim of this work is to present the effect of lignocellulosic compoundson the yield, nanostructure and reactivity of soot. Soot was produced from holocelluloses, extractives, two types of organosolv lignin (softwood and wheat straw), and lignin-derived compounds (syringol, guaiacol, p-hydroxyphenol)at temperature of 1250°Cand residence time of 0.17 sand 0.35 sin a drop tube furnace.Soxhlet extraction was performed on soot samples from pyrolysis of both lignin samplesusing acetone and methanol as a solvent.The structure of solid residues was characterized by transmission electron microscopy and Raman spectroscopy. The reactivity of soot inO2oxidation and CO2gasificationwas investigated by thermogravimetric analysis. The present results indicated that soot yields from pyrolysis of ligninfrom softwood and extractives at 1250°C with the residence time of 0.17 swere similaras shown in Figure 1. The highest soot yield was obtained from pyrolysis of wheat straw lignin and quantitatively comparable with the soot yield of hydroquinone. The presence of hydroxyl groups compared to other lignin-derived compounds representing S-and G-lignin types might enhance the soot formation.Lower soot yields were obtained from pyrolysis of cellulose and hemicellulosedue to the lower presence of inherent aromatic rings [1-3].Moreover, the soot yields from pyrolysis of potassium impregnated lignin at 1250°C with the residence time of 0.35 swere significantly lower than that of non-treated lignin samples indicating the catalytic influence of potassium inhibitinggrowth of polycyclic aromatic hydrocarbons, confirming the previous results of Umeki et al. [4]

  • 5.
    Trubetskaya, Anna
    et al.
    Department of Applied Physics and Electronics , Umeå University.
    Broström, Markus
    Thermochemical Energy Conversion Laboratory (TEC-Lab), Department of Applied Physics and Electronics, Umeå University.
    Talbro Barsberg, Søren
    Department of Geosciences and Natural Ressource Management, University of Copenhagen.
    Development of CO2 neutral reductants in metallurgical industry from thermochemically produced biochar using DFT calculations2017In: Biochar: Production, Characterization and Applications: August 20-25, 2017, Hotel Calissano Alba, Italy, 2017Conference paper (Other academic)
    Abstract [en]

    Carbon is a key ingredient for producing metals used for cellphones, laptop computers, photovoltaic panels, and related solid state silicon devices employed by mankind. Thus, introduction of an alternative reductant based on bioresources into steel manufacturing without significant investments in a new technology is of high importance and wide impact. The production of iron, steel, and many other metalscan employ biocarbon as the needed reductant; but because of cost, coals are usually used instead. The anthropogenic CO2emissions can be decreased by substitution of biochar in the production of silicon and metals due to the lower regeneration time of biomass < 10 years compared to 106-107years for bituminous coal.This study aims to develop and to provide knowledge on the biochar structure at the molecular level including the presence of free radicals and oxygen heteroatoms that is essential for the understanding and prediction of biochar valuable properties in metallurgical applications. Both yields and biochar properties are important parameters for the optimization of pyrolysis conditions. Therefore, the pyrolysis conditions for the biochar application as a reducing agent in steel industry were optimized, and the molecular structure of the biochar by the combined use of experimental chemistry (Raman spectroscopy and Fourier transform infrared spectroscopy) and quantum chemistry computations(DFT)was modified.The results indicated the formation of stable radicals from biomass pyrolysis at their termination stage which were quantified by the electron spin resonance spectroscopy. Based on the experimental and fitting results, PAH structures were selected as initial compounds for the DFT modeling. The comparison of hydroxylated with methylated PAH structures showed that hydroxylated PAH are excellent candidates to represent the radical structure based on the low bond dissociation energies. The bond dissociation energy of -10 Kcal mol-1is in the range of the best know antioxidants. The results showed that the present DFT model predicts reasonable the biochar molecular structure, and can capture changes in the biochar molecular structure under different pyrolysis conditions

  • 6.
    Trubetskaya, Anna
    et al.
    Thermochemical Energy Conversion Laboratory, Umeå University, Umeå.
    Brown, A.
    Chemical Engineering Department, Worcester Polytechnic Institute, Worcester, MA, United States.
    Tompsett, G.A.
    Chemical Engineering Department, Worcester Polytechnic Institute, Worcester, MA, United States.
    Timko, M.T.
    Chemical Engineering Department, Worcester Polytechnic Institute, Worcester, MA, United States.
    Kling, J.
    Center for Nanoscopy, Technical University of Denmark, Kgs. Lyngby, Denmark.
    Broström, M.
    Thermochemical Energy Conversion Laboratory, Umeå University, Umeå.
    Andersen, M.L.
    Department of Food Science, University of Copenhagen, Copenhagen, Denmark.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Characterization and reactivity of soot from fast pyrolysis of lignocellulosic compounds and monolignols2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 212, p. 1489-1500Article in journal (Refereed)
    Abstract [en]

    This study presents the effect of lignocellulosic compounds and monolignols on the yield, nanostructure and reactivity of soot generated at 1250 °C in a drop tube furnace. The structure of soot was characterized by electron microscopy techniques, Raman spectroscopy and electron spin resonance spectroscopy. The CO2 reactivity of soot was investigated by thermogravimetric analysis. Soot from cellulose was more reactive than soot produced from extractives, lignin and monolignols. Soot reactivity was correlated with the separation distances between adjacent graphene layers, as measured using transmission electron microscopy. Particle size, free radical concentration, differences in a degree of curvature and multi-core structures influenced the soot reactivity less than the interlayer separation distances. Soot yield was correlated with the lignin content of the feedstock. The selection of the extraction solvent had a strong influence on the soot reactivity. The Soxhlet extraction of softwood and wheat straw lignin soot using methanol decreased the soot reactivity, whereas acetone extraction had only a modest effect. 

  • 7.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. hermochemical Energy Conversion Laboratory, Umeå University.
    Hofmann Larsen, Flemming
    Department of Food Science, University of Copenhagen.
    Shchukarev, Andrey
    Department of Chemistry, Umeå University.
    Ståhl, Kenny
    Department of Chemistry, Technical University of Denmark.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Potassium and soot interaction in fast biomass pyrolysis at high temperatures2018In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 225, p. 89-94Article in journal (Refereed)
    Abstract [en]

    his study aims to investigate the interaction between potassium and carbonaceous matrix of soot produced from wood and herbaceous biomass pyrolysis at high heating rates at 1250°C in a drop tube reactor. The influence of soot carbon chemistry and potassium content in the original biomass on the CO2 reactivity was studied by thermogravimetric analysis. The XPS results showed that potassium incorporation with oxygen-containing surface groups in the soot matrix did not occur during high temperature pyrolysis. The potassium was mostly found as water-soluble salts such as KCl, KOH, KHCO3 and K2CO3 in herbaceous biomass soot. The low ash-containing pinewood soot was less reactive than the potassium rich herbaceous biomass soot, indicating a dominating role of potassium on the soot reactivity. However, the catalytic effect of potassium on the reactivity remained the same after a certain potassium amount was incorporated in the soot matrix during pyrolysis. Raman spectroscopy results showed that the carbon chemistry of biomass soot also affected the CO2 reactivity. The less reactive pinewood soot was more graphitic than herbaceous biomass soot samples with the disordered carbon structure.

  • 8.
    Trubetskaya, Anna
    et al.
    Mechanical Engineering Department, National University of Ireland Galway.
    Hofmann Larsen, Flemming
    Department of Food Science, University of Copenhagen.
    Shchukarev, Andrey
    Department of Chemistry, Umeå University.
    Ståhl, Kenny
    Department of Chemistry, Technical University of Denmark.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Potassium and soot interaction in fast biomass pyrolysis at high temperatures2018Conference paper (Refereed)
  • 9.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Experimental investigations and modeling of devolatilization based on superimposed kinetics of biomass2016Conference paper (Refereed)
  • 10.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Andersen, Mogens Larsen
    Department of Food Science, University of Copenhagen.
    Talbro Barsberg, Søren
    Department of Geosciences and Natural Ressource Management, University of Copenhagen.
    Characterization of Free Radicals By Electron Spin Resonance Spectroscopy in Biochars from Pyrolysis at High Heating Rates and at High Temperatures2016Conference paper (Refereed)
  • 11.
    Trubetskaya, Anna
    et al.
    DTU Chemical Engineering, Technical University of Denmark.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Garcia Llamas, Angel David
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Kling, Jens
    Center for Electron Nanoscopy , Technical University of Denmark.
    Gardini, Diego
    Center for Electron Nanoscopy , Technical University of Denmark.
    Bates, Richard B.
    MIT, Department of Mechanical Engineering.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Effects of Biomass Feedstock on the Yield and Reactivity of Soot from Fast Pyrolysis at High Temperatures2016Conference paper (Refereed)
  • 12.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Larsen, Flemming Hofmann
    Department of Food Science, University of Copenhagen.
    Andersen, Mogens Larsen
    Department of Food Science, University of Copenhagen.
    Characterization of free radicals by Electron Spin Resonance Spectroscopy in biochars from pyrolysis at high heating rates and at high temperatures2016In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 94, p. 117-129Article in journal (Refereed)
    Abstract [en]

    The concentration and type of free radicals from the decay (termination stage) of pyrolysis at slow and fast heating rates and at high temperatures (above 1000°C) in biomass char have been studied. A room-temperature electron spin resonance spectroscopy study was conducted on original wood, herbaceous biomass, holocelluloses, lignin and their chars, prepared at high temperatures in a wire mesh reactor, an entrained flow reactor, and a tubular reactor. The radical concentrations in the chars from the decay stage range up between 7·1016 and 1.5·1018 spins g−1. The results indicated that the biomass major constituents (cellulose, hemicellulose, lignin) had a minor effect on remaining radical concentrations compared to potassium and silica contents. The higher radical concentrations in the wheat straw chars from the decay stage of pyrolysis in the entrained flow reactor compared to the wood chars were related to the decreased mobility of potassium in the char matrix, leading to the less efficient catalytic effects of potassium on the bond-breaking and radical re-attachments. The high Si levels in the rice husk caused an increase in the char radical concentration compared to the wheat straw because the free radicals were trapped in a char consisting of a molten amorphous silica at heating rates of 103–104 K s−1. The experimental electron spin resonance spectroscopy spectra were analyzed by fitting to simulated data in order to identify radical types, based on g-values and line widths. The results show that at high temperatures, mostly aliphatic radicals (g = 2.0026–2.0028) and PAH radicals (g = 2.0027–2.0031) were formed.

  • 13.
    Trubetskaya, Anna
    et al.
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Llamas, Angel David Garcia
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Gardini, Diego
    Center for Electron Nanoscopy, Technical University of Denmark.
    Kling, Jens
    Center for Electron Nanoscopy, Technical University of Denmark.
    Bates, Richard B.
    MIT, Department of Mechanical Engineering, 02139 Cambridge.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Effects of several types of biomass fuels on the yield, nanostructure and reactivity of soot from fast pyrolysis at high temperatures2016In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 171, p. 468-482Article in journal (Refereed)
    Abstract [en]

    This study presents the effect of biomass origin on the yield, nanostructure and reactivity of soot. Soot was produced from wood and herbaceous biomass pyrolysis at high heating rates and at temperatures of 1250 and 1400 °C in a drop tube furnace. The structure of solid residues was characterized by electron microscopy techniques, X-ray diffraction and N2 adsorption. The reactivity of soot was investigated by thermogravimetric analysis. Results showed that soot generated at 1400 °C was more reactive than soot generated at 1250 °C for all biomass types. Pinewood, beechwood and wheat straw soot demonstrated differences in alkali content, particle size and nanostructure. Potassium was incorporated in the soot matrix and significantly influenced soot reactivity. Pinewood soot particles produced at 1250 °C had a broader particle size range (27.2–263 nm) compared to beechwood soot (33.2–102 nm) and wheat straw soot (11.5–165.3 nm), and contained mainly multi-core structures.

  • 14.
    Trubetskaya, Anna
    et al.
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Llamas, Angel David Garcia
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Effect of fast pyrolysis conditions on biomass solid residues at high temperatures2016In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 143, p. 118-129Article in journal (Refereed)
    Abstract [en]

    Fast pyrolysis of wood and straw was conducted in a drop tube furnace (DTF) and compared with corresponding data from a wire mesh reactor (WMR) to study the influence of temperature (1000-1400)°C, biomass origin (pinewood, beechwood, wheat straw, alfalfa straw), and heating rate (103 °C/s, 104 °C/s) on the char yield and morphology. Scanning electron microscopy (SEM), elemental analysis, and ash compositional analysis were applied to characterize the effect of operational conditions on the solid residues (char, soot) and gaseous products. The char yield from fast pyrolysis in the DTF setup was 3 to 7% (daf) points lower than in the WMR. During fast pyrolysis pinewood underwent drastic morphological transformations, whereas beechwood and straw samples retained the original porous structure of the parental fuel with slight melting on the surface. The particle size of Danish wheat straw char decreased in its half-width with respect to the parental fuel, whereas the alfalfa straw char particle size remained unaltered at higher temperatures. Soot particles in a range from 60 to 300 nm were obtained during fast pyrolysis. The soot yield from herbaceous fuels was lower than from wood samples, possibly due to differences in the content of lignin and resin acids

  • 15.
    Trubetskaya, Anna
    et al.
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Steibel, Markus
    Department of Mechanical Engineering, Institute for Energy Systems, Technical University of Munich.
    Spliethoff, Hartmut
    Department of Mechanical Engineering, Institute for Energy Systems, Technical University of Munich.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Influence of fast pyrolysis conditions on yield and structural transformation of biomass chars2015In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 140, p. 205-214Article in journal (Refereed)
    Abstract [en]

    Fast pyrolysis of biomass (wood, straw, rice husk) and its major components (cellulose, hemicellulose, lignin) was conducted in a wire mesh reactor. The aim of this study was to understand the influence of temperature (350-1400 ∗ C), heating rate (10-3000 ∗ C/s), particle size (0.05-2 mm) and holding time (1-4 s) on the char morphology and char yield. Scanning electron microscopy (SEM) and elemental analysis were conducted to determine the effect of operating conditions on char softening and melting during pyrolysis. The char yield decreased with heating rate for rates ≤ 600 ∗ C/s; above this value a similar biomass char yield was obtained. The potassium content affected the char yield stronger than other minerals, while the distribution of the three major biomass constituents (cellulose, hemicellulose, lignin) affected the char yield only to a minor degree. Moreover, it was found that the heat treatment temperature had a larger influence on the char yield than the heating rate. Scanning electron microscopy indicated different types of biomass char plasticization influenced by the applied temperatures, heating rates, particle sizes and holding times, except for the rice husk char that formed chars with a structure similar to the parental fuel at all conditions. The less severe morphological changes of rice husk char were attributed to a high silica content.

  • 16. Trubetskaya, Anna
    et al.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Stiebel, Markus
    Department of Mechanical Engineering, Institute for Energy Systems, Munich University of Technolog.
    Spliethoff, Hartmuth
    Department of Mechanical Engineering, Institute for Energy Systems, Munich University of Technolog.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Larsen, Flemming Hoffmann
    Department of Food Science, Spectroscopy and Chemometrics, University of Copenhagen.
    Comparison of high temperature chars of wheat straw and rice husk with respect to chemistry, morphology and reactivity2016In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 86, p. 76-87Article in journal (Refereed)
    Abstract [en]

    Fast pyrolysis of wheat straw and rice husk was carried out in an entrained flow reactor at high-temperatures (1000–1500) °C. The collected char was analyzed using X-ray diffractometry, N2-adsorption, scanning electron microscopy, particle size analysis with CAMSIZER XT, 29Si and 13C solid-state nuclear magnetic resonance spectroscopy and thermogravimetric analysis to investigate the effect of inorganic matter on the char morphology and oxygen reactivity. The silicon compounds were dispersed throughout the turbostratic structure of rice husk char in an amorphous phase with a low melting temperature (≈730 °C), which led to the formation of a glassy char shell, resulting in a preserved particle size and shape of chars. The high alkali content in the wheat straw resulted in higher char reactivity, whereas the lower silicon content caused variations in the char shape from cylindrical to near-spherical char particles. The reactivities of pinewood and rice husk chars were similar with respect to oxidation, indicating less influence of silicon oxides on the char reactivity.

  • 17.
    Trubetskaya, Anna
    et al.
    Mechanical Engineering Department, National University of Ireland Galway.
    Kling, Jens
    Center for Electron Nanoscopy, Technical University of Denmark.
    Broström, Markus
    Thermochemical Energy Conversion Laboratory (TEC-Lab), Department of Applied Physics and Electronics, Umeå University.
    Tompsett, Geoffrey
    Chemical Engineering Department, Worcester Polytechnic Institute.
    Timko, Michael T.
    Chemical Engineering Department, Worcester Polytechnic Institute.
    Brown, Avery
    Chemical Engineering Department, Worcester Polytechnic Institute.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Andersen, Mogens Larsen
    Department of Food Science, University of Copenhagen.
    The effect of lignocellulosic compounds and monolignols on the soot nanostructure and CO2 reactivity2018Conference paper (Refereed)
  • 18. Trubetskaya, Anna
    et al.
    Kling, Jens
    Center for Electron Nanoscopy, Technical University of Denmark.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Attard, Thomas M.
    Department of Chemistry, The University of York.
    Budarin, Vitaliy L.
    Department of Chemistry, The University of York.
    Hunt, Andrew J.
    Department of Chemistry, Khon Kaen University.
    Effect of supercritical extraction on the soot nanostructure and gasification product yields2018Conference paper (Refereed)
  • 19.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Poyraz, Yunus
    Institute of Energy Processes Engineering and Fuel Technology, Clausthal University of Technology.
    Weber, Roman
    Institute of Energy Processes Engineering and Fuel Technology, Clausthal University of Technology.
    Wadenbäck, Johan
    Amager power plant, HOFOR A/S.
    Secondary comminution of wood pellets in power plant and laboratory-scale mills2017In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 160, p. 216-227Article in journal (Refereed)
    Abstract [en]

    This study aims to determine the influence of mill type and pellet wood composition on particle size and shape of milled wood. The size and shape characteristics of pellets comminuted using power plant roller mills were compared with those obtained by using laboratory-scale roller- and hammer mills. A 2D dynamic imaging device was used for particle characterization. It was shown that mill type has a significant impact on particle size but an almost negligible effect on the shape of milled wood. Comminution in the pilot plant using a Loesche roller mill requires less energy than using a hammer mill, but generates a larger fraction of coarse particles. The laboratory-scale roller mill provides comparable results with the power plant roller mill with respect to particle size and shape.

  • 20.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Stiebel, Markus
    Department of Mechanical Engineering, Institute for Energy Systems, Munich University of Technolog.
    Spliethoff, Hartmuth
    Department of Mechanical Engineering, Institute for Energy Systems, Munich University of Technolog.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Effect of pyrolysis conditions and composition on the char structure and char yield of biomass chars2014In: PYRO 2014, 2014Conference paper (Refereed)
  • 21.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. DTU Chemical Engineering, Green research center.
    Stiebel, Markus
    Department of Mechanical Engineering, Institute for Energy Systems, Munich University of Technolog.
    Spliethoff, Hartmuth
    Department of Mechanical Engineering, Institute for Energy Systems, Munich University of Technolog.
    Talbro Barsberg, Søren
    Department of Geosciences and Natural Ressource Management, University of Copenhagen.
    Andersen, Mogens Larsen
    Department of Food Science, University of Copenhagen.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Structural and Compositional Transformations of Biomass Chars during Fast Pyrolysis2014In: TCS 2014, 2014Conference paper (Refereed)
  • 22.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Surup, Gerrit
    Department of Engineering Sciences, University of Agder.
    Shapiro, Alexander
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Bates, Richard B.
    MIT, Department of Mechanical Engineering.
    Modeling the influence of potassium content and heating rate on biomass pyrolysis2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 194, p. 199-211Article in journal (Refereed)
    Abstract [en]

    This study presents a combined kinetic and particle model that describes the effect of potassium and heating rate during the fast pyrolysis of woody and herbaceous biomass. The model calculates the mass loss rate, over a wide range of operating conditions relevant to suspension firing. The shrinking particle model considers internal and external heat transfer limitations and incorporates catalytic effects of potassium on the product yields. Modeling parameters were tuned with experimentally determined char yields at high heating rates (>200 K s−1) using a wire mesh reactor, a single particle burner, and a drop tube reactor. The experimental data demonstrated that heating rate and potassium content have significant effects on the char yield. The importance of shrinkage on the devolatilization time becomes greater with increasing particle size, but showed little influence on the char yields.

  • 23.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Surup, Gerrit
    Department of Engineering Sciences, University of Agder.
    Shapiro, Alexander
    Department of Chemical and Biochemical Engineering, Technical University of Denmark.
    Bates, Richard B.
    MIT, Department of Mechanical Engineering.
    Publisher’s Note to Modeling the influence of potassium content and heating rate on biomass pyrolysis [Appl. Energy J. 194 (2017) 199–211]2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 202, p. 785p. 785-Article in journal (Other academic)
  • 24.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Chracterization and prediction of tar formation from fast pyrolysis of lignin2017In: Combustion Flame Days 2017, 2017Conference paper (Refereed)
  • 25.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. DTU Chemical Engineering, Green research center.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Garcia Llamas, Angel David
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Effect of Fast Pyrolysis Conditions on Structural Transformation and Reactivity of Herbaceous Biomasses at High Temperatures2015Conference paper (Refereed)
  • 26.
    Trubetskaya, Anna
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. DTU Chemical Engineering, Green research cente.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Garcia Llamas, Angel David
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Jensen, Anker Degn
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Jensen, Peter Arendt
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Glarborg, Peter
    Department of Chemical and Biochemical Engineering, Denmark Technical University.
    Effect of Fast Pyrolysis Conditions on the Biomass Solid Residues at High Temperatures (1000-1400°C)2015Conference paper (Refereed)
1 - 26 of 26
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