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Boström, Dan
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Publications (10 of 133) Show all publications
Thyrel, M., Backman, R., Boström, D., Skyllberg, U. & Lestander, T. A. (2021). Phase transitions involving Ca - The most abundant ash forming element - In thermal treatment of lignocellulosic biomass. Fuel, 285, Article ID 119054.
Open this publication in new window or tab >>Phase transitions involving Ca - The most abundant ash forming element - In thermal treatment of lignocellulosic biomass
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2021 (English)In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 285, article id 119054Article in journal (Refereed) Published
Abstract [en]

Torrefaction, pyrolysis and gasification are of interest to convert lignocellulosic biomass into fuels and chemicals. These techniques involve thermal treatment at low partial pressures of oxygen. However, little is known about the transformation of ash elements during these processes. The phase transition of the major ash element calcium (Ca) was therefore studied with powder from pine as biomass model treated at temperatures 300-800 degrees C under atmospheres of 100% N-2, 3% O-2 and 6% O-2 and thermodynamic equilibrium modelling. For evaluation, Xray powder diffraction and synchrotron Ca K-edge X-ray absorption near edge structure (XANES) spectroscopy in combination with linear combination fitting and reference compounds was used. The results indicated that the most abundant Ca-containing species in the untreated material was thermally unstable Ca oxalate (CaC2O4) primarily decomposing into Ca phases dominated by carbonates at temperatures up to 600 degrees C. Double carbonates of calcium and potassium were observed in the form of fairchildiite/butscheliite (K2Ca(CO3)(2)), and these phases were stable over the low temperature range studied. Hydroxyapatite (Ca-5(PO4)(3)OH) was expected to be present and thermally stable over the entire temperature interval and was found in untreated material. At temperatures above 600 degrees C calcium oxide (CaO) was formed. The amount of oxygen had little effect on the phase transitions. The results of thermodynamic modeling were in agreement with XANES showing that this is a versatile technique that can be applied to systems as complex as Ca phase transitions in thermally treated lignocellulosic biomass at low partial pressures of oxygen.

Place, publisher, year, edition, pages
Elsevier, 2021
Keywords
Pyrolysis, Calcium phases, Equilibrium modelling, XANES, XRD
National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:umu:diva-179061 (URN)10.1016/j.fuel.2020.119054 (DOI)000588132400026 ()2-s2.0-85090129992 (Scopus ID)
Available from: 2021-01-29 Created: 2021-01-29 Last updated: 2023-03-23Bibliographically approved
Rebbling, A., Sundberg, P., Fagerström, J., Carlborg, M., Tullin, C., Boström, D., . . . Skoglund, N. (2020). Demonstrating Fuel Design To Reduce Particulate Emissions and Control Slagging in Industrial-Scale Grate Combustion of Woody Biomass. Energy & Fuels, 34(2), 2574-2583
Open this publication in new window or tab >>Demonstrating Fuel Design To Reduce Particulate Emissions and Control Slagging in Industrial-Scale Grate Combustion of Woody Biomass
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2020 (English)In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 34, no 2, p. 2574-2583Article in journal (Refereed) Published
Abstract [en]

The demand for increased overall efficiency, improved fuel flexibility, and more stringent environmental legislations promotes the development of new fuel- and technology-related concepts for the bioenergy sector. Previous research has shown that careful consideration of the fuel ash composition and the adjustment of the same via various routes, i.e., fuel design, have the potential to alter the ash transformation reactions, leading to, e.g., a reduction of the formation of slag or entrained inorganic ash particles. The objective of the present work was, therefore, to demonstrate the use of fuel design as a primary measure to reduce the emission of PM1 during combustion of woody biomass in medium-scale grate-fired boilers while keeping the slag formation at a manageable level. This was achieved by designing fuel blends of woody biomass with carefully selected Scandinavian peats rich in Si, Ca, and S. The work includes results from three experimental campaigns, performed in three separate grate-fired boilers of different sizes, specifically 0.2 MWth, 2 MWth, and 4 MWth. In one of the campaigns, softwood-based stemwood pellets were copelletized with different additions of peat (5 and 15 wt %) before combustion. In the other campaigns, peat was added in a separate fuel feed to Salix chips (15 wt % peat) and softwood-based stemwood pellets (10 and 20 wt % peat). Particulate matter and bottom ashes were characterized by scanning electron microscopy-energy-dispersive X-ray spectroscopy for morphology and elemental composition as well as by powder X-ray diffraction for crystalline phase composition. The results show that the fuel design approach provided PM1 reduction for all fuel blends between 30 and 50%. The PM1 reduction could be achieved without causing operational problems due to slagging for any of the three commercial boilers used, although an expected increased slagging tendency was observed. Overall, this paper illustrates that fuel design can be implemented on an industrial scale by achieving the desired ash transformation reactions, in this case, leading to a reduction of fine particulate emissions by up to 50% without any operational disturbances due to slag formation on the grate.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2020
Keywords
Redox reactions, Reaction products, Biomass, Fuels, Particulate matter
National Category
Energy Engineering
Identifiers
urn:nbn:se:umu:diva-169362 (URN)10.1021/acs.energyfuels.9b03935 (DOI)000518215400147 ()2-s2.0-85080925129 (Scopus ID)
Projects
Bio4Energy
Funder
Bio4Energy
Available from: 2020-04-07 Created: 2020-04-07 Last updated: 2023-03-24Bibliographically approved
Rebbling, A., Näzelius, I.-L., Schwabl, M., Feldmeier, S., Schön, C., Dahl, J., . . . Boman, C. (2020). Prediction of slag related problems during fixed bed combustion of biomass by application of a multivariate statistical approach on fuel properties and burner technology. Biomass and Bioenergy, 137, Article ID 105557.
Open this publication in new window or tab >>Prediction of slag related problems during fixed bed combustion of biomass by application of a multivariate statistical approach on fuel properties and burner technology
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2020 (English)In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 137, article id 105557Article in journal (Refereed) Published
Abstract [en]

Slag is related to the melting properties of ash and is affected by both the chemical composition of the fuel ash and the combustion parameters. Chemical analysis of slag from fixed bed combustion of phosphorus-poor biomass show that the main constituents are Si, Ca, K, O (and some Mg, Al, and Na), which indicates that the slag consists of different silicates. Earlier research also points out viscosity and fraction of the ash that melts, as crucial parameters for slag formation. To the authors’ knowledge, very few of the papers published to this day discuss slagging problems of different pelletized fuels combusted in multiple combustion appliances. Furthermore, no comprehensive classification of both burner technology and fuel ash parameters has been presented in the literature so far. The objective of the present paper was therefore to give a first description of a qualitative model where ash content, concentrations of main ash forming elements in the fuel and type of combustion appliance are related to slagging behaviour and potential operational problems of a biomass fuel in different small- and medium scale fixed bed appliances. Based on the results from the combustion of a wide range of pelletized biomass fuels in nine different burners, a model is presented for amount of slag formed and expected severity of operational problems. The model was validated by data collected from extensive combustion experiments and it can be concluded that the model predicts qualitative results.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Biomass, Combustion, Fixed bed, Slagging, Predictive model
National Category
Chemical Engineering
Identifiers
urn:nbn:se:umu:diva-165223 (URN)10.1016/j.biombioe.2020.105557 (DOI)000536426600012 ()2-s2.0-85083419587 (Scopus ID)
Funder
EU, European Research Council, 287062Bio4Energy
Note

Originally included in thesis in manuscript form.

Available from: 2019-11-15 Created: 2019-11-15 Last updated: 2020-06-29Bibliographically approved
Skoglund, N., Strandberg, A., Öhman, M. & Boström, D. (2019). Elemental approaches to additives: mechanisms and dosage. In: : . Paper presented at World Sustainable Energy Days, REFAWOOD workshop session, 28 February, 2019, Wels, Austria.
Open this publication in new window or tab >>Elemental approaches to additives: mechanisms and dosage
2019 (English)Conference paper, Oral presentation only (Other academic)
National Category
Energy Engineering
Identifiers
urn:nbn:se:umu:diva-157287 (URN)
Conference
World Sustainable Energy Days, REFAWOOD workshop session, 28 February, 2019, Wels, Austria
Note

Funded by the ERA-NET project REFAWOOD

Available from: 2019-03-13 Created: 2019-03-13 Last updated: 2020-02-24Bibliographically approved
Viggh, E., Boström, D. & Wilhelmsson, B. (2019). Raw meal and slag reactions during cement clinker formation. In: : . Paper presented at 15th International Congress on the Chemistry of Cement, Prague, Czech Republic, September 16–20, 2019.
Open this publication in new window or tab >>Raw meal and slag reactions during cement clinker formation
2019 (English)Conference paper, Oral presentation only (Other academic)
Abstract [en]

Natural limestones as raw material for OPC clinker manufacturing contribute to emissions of CO2gases during the production of clinker. In addition, the mining of limestone can regionally be controlledby restrictions due to environmental concerns. Slags from the steel industry can replace limestone tominimize the use of the mineral deposits. Both materials have similar chemistry and are compatible asraw materials.Utilizing slags raises questions about how slag particles will react with other raw meal components asthe temperature in the kiln increases during clinker formation. This study establishes the chemical andmineralogical aspects of replacing a portion of the limestone with slags. Of interest is how the materialsreact during the formation of the liquid phase and the formation of phases containing MgO.Three different slags were examined, a basic oxygen furnace slag BOF, a crystalline blast-furnace slagand a granulated blast-furnace slag. In the study, the microstructural causes of reactivity, as well asmineral formation in the transition zone between raw meal components, developing liquid phase andslag particles were studied. Heated raw meals were studied using HT-QXRD, QXRD, SEM andthermodynamic modeling to describe the reactions of particles at higher temperatures. The resultsshow that the formation of clinker minerals is strongly influenced by the type and amount of slag. Thus,a careful selection must be done of both composition and quantity of metallurgical slags for naturallimestone replacement in order to maintain clinker quality.

National Category
Chemical Engineering
Identifiers
urn:nbn:se:umu:diva-162764 (URN)
Conference
15th International Congress on the Chemistry of Cement, Prague, Czech Republic, September 16–20, 2019
Available from: 2019-08-28 Created: 2019-08-28 Last updated: 2023-08-21Bibliographically approved
Falk, J., Skoglund, N., Grimm, A., Boström, D. & Öhman, M. (2018). Difference in phosphate speciation between sewage sludge and biomass ash from fluidized bed combustion. In: 27th International Conference of Impacts of Fuel Quality on Power Production and the Environment, September 23–28 September, 2018, Lake Louise, Canada: . Paper presented at International Conference on the Impact of Fuel Quality on Power Production and the Environment.
Open this publication in new window or tab >>Difference in phosphate speciation between sewage sludge and biomass ash from fluidized bed combustion
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2018 (English)In: 27th International Conference of Impacts of Fuel Quality on Power Production and the Environment, September 23–28 September, 2018, Lake Louise, Canada, 2018Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

The role of phosphorus in biomass combustion is a topic that has become increasingly relevantin recent years. Due to the demand for new sources of renewable energy and recovery of phosphorus from waste streams such as sewage sludge, research into the behavior of phosphorus during combustion is necessary for a continued development. This study aims to investigate potential differences in phosphate behavior during co-combustion of sewage sludge compared to other phosphorus-rich biomass or additives. The investigation was carried out in a bench scale bubbling fluidized bed, co-combusting six biomass blends of similar ash composition and combustion conditions but with different phosphorus association (logging residues (LR) or wheat straw (WS) with sewage sludge (SS), dried distiller’s grain (DG), or phosphoric acid (PA)). After combustion, bed ash samples, fly ash deposits and cyclone ash were collected and analyzed for elemental composition (SEM-EDS) and phase composition (XRD). Based on the XRD phase analyses, a significant difference in phosphate speciation were foundbetween biomass blends containing SS compare to DG or PA. Only two phosphate phases were identified in the ash from SS blends compared to a large variety of phosphates in ash from DG or PA blends. The difference in speciation could not be explained by a difference in ash fractionation as the elemental composition of the analyzed ash fractions were similar. Rather, the results indicate that the behavior of phosphorus in SS may be different to that in DG or PA.

National Category
Energy Engineering Other Chemistry Topics
Identifiers
urn:nbn:se:umu:diva-157280 (URN)
Conference
International Conference on the Impact of Fuel Quality on Power Production and the Environment
Funder
Swedish Research Council Formas, 2015-619
Available from: 2019-03-13 Created: 2019-03-13 Last updated: 2019-03-18Bibliographically approved
Skoglund, N., Kuba, M., Boström, D. & Öhman, M. (2018). Effects of Bed Material Type and Fuel Ash Composition on Layer Formation and Bed Agglomeration in Thermo-chemical Conversion of Biomass and Waste Streams in Fluidized Beds. In: 23rd International Conference on Fluidized Bed Conversion, 13-17 May 2018, Seoul, Korea: . Paper presented at 23rd International Conference on Fluidized Bed Conversion, 13-17 May 2018, Seoul, Korea.
Open this publication in new window or tab >>Effects of Bed Material Type and Fuel Ash Composition on Layer Formation and Bed Agglomeration in Thermo-chemical Conversion of Biomass and Waste Streams in Fluidized Beds
2018 (English)In: 23rd International Conference on Fluidized Bed Conversion, 13-17 May 2018, Seoul, Korea, 2018Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

The role of fluidized beds is increasingly important for challenging and ash-rich fuels, such as fast-growing biomass and waste streams. From a biomass perspective, the relatively homogeneous woody-type fuels are most commonly used in fluidized beds today whereas the fuel feedstock for waste streams is more heterogeneous. A key issue in enabling a broader fuel feedstock for existing and planned fluidized beds is how the fuel ash interacts with bed materials of different types during combustion or gasification. The resulting bed particle coating, layers, and cracks formed in bed grains are responsible for bed agglomeration and bed material deposition mechanisms, but studies have suggested that there is a possibility to affect melting temperatures of bed ash and reduce interaction between fuel ash and bed material through additives or by fuel blend design. Furthermore, it is of interest to extend the life-time of bed materials in the reactor to reduce the amount of material that is generated as waste streams, as well as increase the timespan between bed replacements.The aim of this review is therefore to summarize some of our previous research in this topic, to discuss current knowledge concerning layer formation and bed agglomeration mechanisms, address the benefit for different bed materials, and discuss how fuel ash composition can be used to reduce bed agglomeration issues. This is achieved by comparing studies from different combustion and gasification facilities using different biomasses as well as agricultural residues and waste streams. In particular, the possibility of using fuel blend design to reduce interaction of fuel ash with bed material will be highlighted. Using such approaches, coupled with a fundamental understanding of how differences between bed materials affect layer formation mechanisms, has the potential to reduce operational issues caused by interactions between fuel ash and bed materials as well as increase the potential fuel feedstock.

Keywords
bed particle layer formation, bed agglomeration, biomass, waste, combustion, gasification
National Category
Energy Engineering Inorganic Chemistry
Identifiers
urn:nbn:se:umu:diva-148077 (URN)
Conference
23rd International Conference on Fluidized Bed Conversion, 13-17 May 2018, Seoul, Korea
Available from: 2018-05-25 Created: 2018-05-25 Last updated: 2018-08-07Bibliographically approved
Konwar, L. J., Samikannu, A., Mäki-Arvela, P., Boström, D. & Mikkola, J.-P. (2018). Lignosulfonate-based macro/mesoporous solid protonic acids for acetalization of glycerol to bio-additives. Applied Catalysis B: Environmental, 220, 314-323
Open this publication in new window or tab >>Lignosulfonate-based macro/mesoporous solid protonic acids for acetalization of glycerol to bio-additives
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2018 (English)In: Applied Catalysis B: Environmental, ISSN 0926-3373, E-ISSN 1873-3883, Vol. 220, p. 314-323Article in journal (Refereed) Published
Abstract [en]

The enclosed paper introduces a novel, scalable and environmentally benign process for making strongly acidic solid meso/macroporous carbon catalysts from Na-lignosulfonate (LS), a byproduct from sulfite pulping. Ice-templated LS was converted to strongly acidic macro/mesoporous solid protonic acids via mild pyrolysis (350–450 °C) and ion/H+ exchanging technique. The synthesized materials were extensively characterized by FT-IR, Raman, XRD, XPS, TGA, FE-SEM, TEM and N2-physisorption methods. These LS derived materials exhibited a macro/mesoporous and highly functionalized heteroatom doped (O, S) carbon structure with large amounts of surface OH, COOH and SO3H groups similar to the sulfonated carbon materials. Further, these carbon materials showed excellent potential as solid acid catalysts upon acetalization of glycerol with various bio-based aldehydes and ketones (acetone, methyl levulinate and furfural), easily outperforming the commercial acid exchange resins (Amberlite® IR120 and Amberlyst® 70). Most importantly, the optimum LS catalyst exhibiting a large specific surface area demonstrated exceptional potential for continuous solketal production (liquid phase atmospheric pressure operation) maintaining its activity (glycerol conversion ≥ 91%) and structural features even after 90 h time on stream.

Place, publisher, year, edition, pages
Amsterdam: Elsevier, 2018
Keywords
Solid sulfonic acids, Glycerol acetalization, Bio-additives, Solketal, Lignosulfonate
National Category
Chemical Sciences
Identifiers
urn:nbn:se:umu:diva-139656 (URN)10.1016/j.apcatb.2017.08.061 (DOI)000412957200030 ()2-s2.0-85028309107 (Scopus ID)
Projects
Bio4Energy
Funder
Bio4Energy
Available from: 2017-09-20 Created: 2017-09-20 Last updated: 2023-03-23Bibliographically approved
Zhu, Y., van Eyk, P. J., Boman, C., Broström, M., Kirtania, K., Piotrowska, P., . . . Ashman, P. J. (2018). Preliminary understanding on the ash behavior of algae during co-gasification in an entrained flow reactor. Fuel processing technology, 175, 26-34
Open this publication in new window or tab >>Preliminary understanding on the ash behavior of algae during co-gasification in an entrained flow reactor
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2018 (English)In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 175, p. 26-34Article in journal (Refereed) Published
Abstract [en]

Algae are considered as a promising alternative fuel to produce energy due to its advantages such as high production yield, short growth cycle and flexible growing environment. Unfortunately, ash-related issues restrict its thermochemical utilization due to the high ash content and especially the high alkali metal concentration. In this paper, the gasification performance and ash behavior were experimentally analysed for three macro- and micro-algal species. Clear differences in the proximate and ultimate compositions were found between the cultivated algae used in this study and macroalgae (seaweed) harvested from the marine environments. Algal biomass generally contained higher Na and P contents than lignocellulosic biomass. Microalgae also had a relatively high mineral content due to the impurities in the harvesting process which included centrifugal pumping followed by sedimentation. Co-gasification of 20 wt% algae with softwood was investigated using an entrained flow reactor. The addition of both macroalgal species Derbersia tenuissima and Oedogonium to softwood had a limited influence on the gas yields and carbon conversion. On the other hand, the addition of the microalgal species Scenedesmus significantly decreased the main gas yields and carbon conversion. Moreover, the addition of algae clearly changed the residual ash composition of the base fuel. Finally, a preliminary understanding of the ash behavior of the tested algae blends was obtained through the analysis of the fuel ashes and the collected residual ashes. Fouling and corrosion were presumably occurred during the co-gasification of wood/macroalgae blends in view of the high alkali metal content. Microalga Scenedesmus had a high mineral content which could potentially capture the alkali metal in the ash and mitigate fouling when gasified with softwood. The growing environment and harvesting method were found to be significantly affecting the ash behavior implying the need for careful consideration regarding co-gasification process.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
algae, ash behavior, co-gasification, fouling, ash transformation
National Category
Energy Engineering Bioenergy
Identifiers
urn:nbn:se:umu:diva-147730 (URN)10.1016/j.fuproc.2018.02.028 (DOI)000432100300004 ()2-s2.0-85042857511 (Scopus ID)
Projects
Bio4Energy
Funder
Bio4Energy
Available from: 2018-05-16 Created: 2018-05-16 Last updated: 2020-07-01Bibliographically approved
Wei, M., Andersson, R., Xie, G., Salehi, S., Boström, D. & Xiong, S. (2018). Properties of Cassava Stem Starch Being a New Starch Resource. Starke (Weinheim), 70(5–6), Article ID 1700125.
Open this publication in new window or tab >>Properties of Cassava Stem Starch Being a New Starch Resource
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2018 (English)In: Starke (Weinheim), ISSN 0038-9056, E-ISSN 1521-379X, Vol. 70, no 5–6, article id 1700125Article in journal (Refereed) Published
Abstract [en]

This study aims to understand the starch properties of cassava stems, currently a discarded crop residue, which contain up to 40% starch by dry mass. Granule sizes and size distribution of cassava stem starch, and their variations with genotype, growing location, and position along the stem are investigated using scanning electron microscopy (SEM) images. Amylose contents, crystallinity, and pasting characteristics of stem and root starch are also compared. The mean of granule sizes range from 5.65 to 7.64 µm, depending on the environment and position along stems, but not on genotype. Stem starch has a similar granule shape, X-ray diffraction pattern, and amylose content (20.8% of starch basis) to root starch, but a significantly smaller granule size with narrower distribution range and higher pasting temperature (72.1 degrees C). Cassava stem has a woody nature; a development of an efficient starch isolation method shall be included in future studies.

Place, publisher, year, edition, pages
John Wiley & Sons, 2018
Keywords
amylose content, crop residues, crystallinity, starch granule size, gelatinization
National Category
Food Science
Identifiers
urn:nbn:se:umu:diva-148022 (URN)10.1002/star.201700125 (DOI)000431735200002 ()2-s2.0-85041613218 (Scopus ID)
Projects
Bio4Energy
Funder
Bio4Energy
Available from: 2018-05-30 Created: 2018-05-30 Last updated: 2023-03-23Bibliographically approved
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