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  • 1.
    Chen, Xu
    et al.
    State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, China.
    Yang, Haiping
    State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, China.
    Chen, Yingquan
    State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, China.
    Chen, Wei
    State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, China.
    Lei, Tingzhou
    Henan Academy of Sciences Institute of Energy Co., Ltd, Zhengzhou, Henan, China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Chen, Hanping
    State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, China.
    Catalytic fast pyrolysis of biomass to produce furfural using heterogeneous catalysts2017In: Journal of Analytical and Applied Pyrolysis, ISSN 0165-2370, E-ISSN 1873-250X, Vol. 127, p. 292-298Article in journal (Refereed)
    Abstract [en]

    Furfural is a valuable chemical, the production of furfural from renewable biomass resources becomes more attractive in recent years. In this study, biomass fast pyrolysis with heterogeneous catalysts (titanium compounds (TiN, TiO2 and TiOSO4) and metal nitrides (MoN, GaN and VN)) for furfural production was investigated experimentally by means of pyrolysis-gas chromatography/mass-spectrometry (Py-GC/MS). The measurement results indicated that TiN and GaN promoted the furfural compounds production notably mainly through direct decomposition of oligosaccharides. The formation of furfural was promoted when the amount of TiN was increased, and the yield of furfural formed was about 5.5 times the size of that from non-catalytic pyrolysis when TiN/cellulose mass ratio was 4. The furfural yield decreased when the pyrolysis residence time increased from 10 to 30 s, which suggests competitive reactions (formation of 1, 6-anhydro-beta.-D-glucopyranose) against the formation of furfural. TiN, as a catalyst for fast pyrolysis towards furfural production, can be well applied to agriculture biomass residues. Comparing three biomass residues: corncob, wheat straw and cotton stalk, corncob showed higher furfural yield due to the higher holocellulose content, while wheat straw showed higher furfural selectivity. 

  • 2. Chunjiang, Y
    et al.
    Tabikl, A
    Leckner, Bo
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Modeling of deposition and emission of alkalis in boiler systems: Mid-term reporting for project JOR3CT980306 of 4th EU-framework Programme2000Report (Other scientific)
  • 3.
    Ding, Mingyue
    et al.
    Wuhan University, China.
    Ma, Longlong
    Chinese Academy of Sciences, China.
    Zhang, Qian
    Chinese Academy of Sciences, China.
    Wang, Chenguang
    Chinese Academy of Sciences, China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Wang, Tiejun
    Chinese Academy of Sciences, China.
    Enhancement of conversion from bio-syngas to higher alcohols fuels over K-promoted Cu-Fe bimodal pore catalysts2017In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 159, p. 436-441Article in journal (Refereed)
    Abstract [en]

    A novel K-promoted Cu-Fe bimodal derived catalyst was designed to optimize the catalytic activity and higher alcohols selectivity in higher alcohols synthesis (HAS). The characterization results indicated that the Cu-Fe bimodal derived catalyst presented the bimodal pore structures. The adding of K promoter increased the BET surface area and promoted the dispersion of Cu and Fe species in the bimodal pores without destroying the bimodal structure, whereas the excessive adding of potassium resulted in easily the aggregation of bimetal active species. Incorporation of moderate K content enhanced the reduction of Cu and Fe species and promoted the formation of active bimetal species for HAS, while the bimodal derived catalyst with excessive K content restrained the reduction of bimetal particles, decreasing the catalytic activity for higher alcohols synthesis. In addition, the gradual increasing of K content in the Cu-Fe bimodal derived catalyst strengthened the interaction of K and bimetal active species, which was combined with the “confinement effect” of bimodal pore structures, shifting product distribution towards C2 + OH.

  • 4.
    Forsman, Björn
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Alkali Metal Release During Rapid Pyrolysis of Fuel Blends Containing 2005In: Proceedings. 14th European conference and technology exhibition biomass for energy industry and climate protection, Paris, Oct. 2005, 2005Conference paper (Other scientific)
    Abstract [en]

    In the present study the influence of different fuel blends and additives on the release of gaseous alkali metals during rapid pyrolysis of biomass has been investigated. A single particle reactor has been used together with a molecular beam mass spectrometer (MBMS) to study the release of gaseous alkali-containing emissions during pyrolysis. A hot platinum filament was used as the ionization source and alkali-containing compounds that hit the hot filament dissociate and alkali ions leave the Pt -filament and are detected in the MBMS. The fuels used were wood (spruce) and wood waste. The additives included peat, different sewage sludge samples, sludge from the pulp and paper industry and fly ash from co-combusted wood and sewage sludge. Experimental results show time resolved mass loss curves of biomass particles during rapid pyrolysis combined with released amounts of sodium (Na) and potassium (K). The results indicate that the new combined instrument successfully detects gaseous alkali metals, and a difference in the release of Na and K during pyrolysis due to the use of the additives is observed. Additives consisting of sewage sludge ash reduced the release of alkali, probably due to the presence of mullite in the ash together with the sorption effect of fine particles.

  • 5.
    Forsman, Björn
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Svenson, J.
    Pettersson, J.B.C.
    ALKALI METAL RELEASE DURING RAPID PYROLYSIS OF FUEL BLENDS CONTAINING BIOMASS AND DIFFERENT ADDITIVES.2005In: Proceedings of the 14th European Biomass Conference: Biomass for Energy, Industry and Climate Protection, 2005Conference paper (Other academic)
  • 6.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    An experimental study on catalytic bed materials in a biomass dual fluidised bed gasifier2015In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 81, p. 251-261Article in journal (Refereed)
    Abstract [en]

    A study on in-bed material catalytic reforming of tar/CH4 has been performed in the 150 kW allothermal gasifier at Mid Sweden University (MIUN). The major challenge in biomass fluidised-bed gasification to produce high-quality syngas, is the reforming of tars and CH4. The MIUN gasifier has a unique design suitable for in-bed tar/CH4 catalytic reforming and continuously internal regeneration of the reactive bed material. This paper evaluates the catalytic effects of olivine and Fe-impregnated olivine (10%wtFe/olivine Catalyst) with reference to silica sand in the MIUN dual fluidised bed (DFB) gasifier. Furthermore, a comparative experimental test is carried out with the same operation condition and bed-materials when the gasifier is operated in the mode of single bubbling fluidised bed (BFB), in order to detect the internal regeneration of the catalytic bed materials in the DFB operation. The behaviour of catalytic and non-catalytic bed materials differs when they are used in the DFB and the BFB. Fe/olivine and olivine in the BFB mode give lower tar and CH4 content together with higher H-2 + CO concentration, and higher H-2/CO ratio, compared to DFB mode. It is hard to show a clear advantage of Fe/olivine over olivine regarding tar/CH4 catalytic reforming. (C) 2015 Elsevier Ltd. All rights reserved.

  • 7.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    He, Jie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Review of syngas production via biomass DFBGs2011In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 15, no 1, p. 482-492Article, review/survey (Refereed)
    Abstract [en]

    Production of high-quality syngas from biomass gasification in a dual fluidised bed gasifier (DFBG) has made a significant progress in R&D and Technology demonstration. An S&M scale bio-automotive fuel plant close to the feedstock resources is preferable as biomass feedstock is widely sparse and has relatively low density, low heating value and high moisture content. This requires a simple, reliable and cost-effective production of clean and good quality syngas. Indirect DFBGs, with steam as the gasification agent, produces a syngas of high content H2 and CO with 12-20 MJ/mn3 heating value. A good quality syngas from DFBGs can be obtained by optimised design and operation of the gasifier, by the use of active catalytic bed materials including internal reforming of tars and methane, and finally by a downstream cleaning process. This article reviews the whole process from gasification to high quality syngas. © 2010 Elsevier Ltd. All rights reserved.

  • 8.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Henschel, Till
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Internal tar/CH4 reforming in a biomass dual fluidised bed gasifier2014In: Proceeding of 4th International Symposium on Gasification and its Applications, 2014Conference paper (Other academic)
    Abstract [en]

    An internal reformer is developed for in-situ catalytic reforming of tar and methane (CH4) in allothermal gasifiers. The study has been performed in the 150 kW dual fluidised bed (DFB) biomass gasifier at Mid Sweden University (MIUN). The MIUN gasifier is built for research on synthetic fuel production. Reduction of tars and CH4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass fluidised-bed gasification technology towards automotive fuel production. The MIUN gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents a study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH4 content. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6% in the syngas. The novel design in the MIUN gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality

  • 9.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Henschel, Till
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Internal tar/CHreforming in a biomass dual fluidised bed gasifier.2015In: Biomass Conversion and Biorefinery, ISSN 2190-6815, Vol. 5, p. 355-366Article in journal (Refereed)
    Abstract [en]

    An internal reformer is developed for in situ catalyticreforming of tar and methane (CH4) in allothermal gasifiers.The study has been performed in the 150 kW dual fluidised bed (DFB) biomass gasifier at Mid Sweden University(MIUN). The MIUN gasifier is built for research onsynthetic fuel production. Reduction of tars and CH4 (exceptfor methanation application) in the syngas is a major challengefor commercialization of biomass fluidised-bed gasificationtechnology towards automotive fuel production. The MIUN gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH4 content. A novel application of Ni-catalyst in DFB gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.

  • 10.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Biogas production from biological methanation of syngas2018In: European Biomass Conference and Exhibition Proceedings, ETA-Florence Renewable Energies , 2018, no 26thEUBCE, p. 512-515Conference paper (Refereed)
    Abstract [en]

    Biogas to be used as gas vehicle fuel is a highly potential source to meet transport fuel demand and give a significant contribution to the Swedish target: vehicle fleet independent of fossil fuels by 2030. At present the biogas market is limited by the amount of available organic waste and the associated infrastructure. To overcome these issues, biomass could either be gasified into syngas and synthesized into bio-SNG (Synthetic Natural Gas) through catalytic methanation, or biomass gasification could be integrated into the biogas system to produce methane through biological methanation. Biomass gasification integrated in biological methanation is a relatively new idea and technology. Syngas conversion to methane by anaerobic cultures is practically unexplored, and few reports are available on this subject. Nevertheless, the pathway has been receiving intensive attractions and R&D recent years. For this purpose, a novel pathway by integrating biomass gasification into biogas system is studied in detail. This paper reviews the whole process from integration of biomass gasification into the biogas system to methane production through biological methanation: Biomass gasification > H2+CO > Biogas digester > Upgrading > Natural gas network. 

  • 11.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    BTL laboratory at Mid Sweden University2008In: 16th European Biomass Conference, Florence: Italy , 2008, p. 1041-1045Conference paper (Refereed)
    Abstract [en]

    This paper presents the BTL (biomass to liquids) laboratory of MIUN (Mid Sweden University) for production of bio-automotive fuels through biomass gasification. The process is intended to be realized in laboratory scale at MIUN with focus on key issues in the BTL technology development. Thus, the BTL laboratory becomes a resource for BTL education, research and development. The BTL laboratory is based on indirect gasification and the gasifier is a combination of a BFB steam gasifier and a CFB combustion riser. The biomass feeding system is unique in application. The syngas is automatically sampled and analyzed on-line on demand. Considering small & medium scale bio-automotive fuel plant, an oxygen plant would be too expensive to be integrated in BTL systems. An indirect gasifier is thus the choice for development to obtain a good quality high energy content synthesis gas. Based on calculation work performed by TPS, the most energy effective gasification technique is indirectly fluidized bed gasification with steam as the gasification agent. Integration of the gasifier and FT/DME/EtOH-reactors will be emphasized and a theoretic BTL model will be developed. The plan is to develop an effective and a reliable BTL technology under 100 MW possible for bio refinery integration.

  • 12.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    CATALYTIC REDUCTION OF TAR/CH4 BY AN INTERNAL REFORMER IN A DFB GASIFIER2014In: European Biomass Conference & Exhibition Proceedings, 2014, p. 620-625Conference paper (Other academic)
    Abstract [en]

    An internal reformer is developed for in-situ catalytic reforming of tar and methane (CH4) in allothermal gasifiers. Reduction of tars and CH4 in the syngas is a challenge for commercialization of biomass fluidised-bed gasification technology towards advanced automotive fuel production. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets in the Mid Sweden University (MIUN) DFB (Dual Fluidised Bed) gasifier, by evaluation of the syngas composition and tar/CH4 content. The novelty with the application of Ni-catalyst in this paper is the selected location where intensive gas to catalytic-material and bed-material contacts improve the reforming reactions. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6% in the syngas. The tar content will be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.  

  • 13.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Experimental test on a novel dual fluidised bed biomass gasifier for synthetic fuel production2011In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 90, no 4, p. 1340-1349Article in journal (Refereed)
    Abstract [en]

    This article presents a preliminary test on the 150 kWth allothermal biomass gasifier at MIUN (Mid Sweden University) in Härnösand, Sweden. The MIUN gasifier is a combination of a fluidised bed gasifier and a CFB riser as a combustor with a design suitable for in-built tar/CH4 catalytic reforming. The test was carried out by two steps: 1) fluid-dynamic study; 2) measurements of gas composition and tar. A novel solid circulation measurement system which works at high bed temperatures is developed in the presented work. The results show the dependency of bed material circulation rate on the superficial gas velocity in the combustor, the bed material inventory and the aeration of solids flow between the bottoms of the gasifier and the combustor. A strong influence of circulation rate on the temperature difference between the combustor and the gasifier was identified. The syngas analysis showed that, as steam/biomass (S/B) ratio increases, CH4 content decreases and H2/CO ratio increases. Furthermore the total tar content decreases with increasing steam/biomass ratio and increasing temperature.  The biomass gasification technology at MIUN is simple, cheap, reliable, and can obtain a syngas of high CO+H2concentration with sufficient high ratio of H2 to CO, which may be suitable for synthesis of Methane, DME, FT-fuels or alcohol fuels. The measurement results of MIUN gasifier have been compared with other gasifiers. The main differences can be observed in the H2 and the CO content, as well as the tar content. These can be explained by differences in the feed systems, operating temperature, S/B ratio or bed material catalytic effect etc..

  • 14.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Internal Tar/CH4 Reforming using a Novel Design in a Biomass Dual Fluidised Bed Gasifier2013In: 21st European Biomass Conference and Exhibition: Setting the course for a biobased ecomomy, Florence, Italy: ETA-Florence Renewable Energies , 2013, p. 2038-2042Conference paper (Other academic)
    Abstract [en]

    Reforming of tars and methane (CH4) in syngas is a significant challenge for low-temperature biomass gasification. For a dual fluidised bed gasifier (DFBG), catalytic bed materials are usually used to promote the reforming reactions. Intensive contact between gas and catalytic bed material at high temperature enhances the internal tar/CH4 reforming. The MIUN gasifier, built for research into synthetic fuel production, is a dual fluidised bed gasifier (DFBG). The results with different bed materials (silica sand, olivine and Fe-impregnated olivine) give roughly equivalent amounts of methane and gravimetric tar in the raw untreated syngas, and need to be reduced to an acceptably low level. The gasification research group at MIUN investigates a novel design in the MIUN gasifier, to increase the gasification efficiency, suppress the tar generation and to upgrade the syngas quality. The first step is taken towards a novel design in the MIUN gasifier. The application is expected to significantly enhance the syngas quality.

  • 15.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Preliminary Test on the Allothermal Gasifier at Mid Sweden University2009In: 17th European Biomass Conference: FROM RESEARCH TO INDUSTRY AND MARKETS / [ed] G. F. DE SANTI, J. F. DALLEMAND, H. OSSENBRINK, A. GRASSI and P. HELM, Florence, Italy: ETA-Florence Renewable Energies , 2009Conference paper (Other academic)
    Abstract [en]

    This paper presents a preliminary test on the 150 kW allothermal biomass gasifier at MSU (Mid Sweden University) in Härnösand, Sweden. The MSU gasifier is a combination of a fluidized bed gasifier and a CFB riser as a combustor with an unique design suitable for in-built tar/CH4 catalytic reforming. The test was carried out by two steps, 1) fluid-dynamic study and 2) measurements of gas composition. The results show the dependency of bed material circulation rate on the superficial gas velocity in the combustor, the bed material inventory and the aeration of solids flow between the bottoms of the gasifier and the combustor. A strong influence of circulation rate on the temperature difference between the combustor and the gasifier was identified. The syngas analysis showed that, as steam/biomass ratio increases, CH4 content decreases and H2/CO ratio increases. The biomass gasification technology developed at MSU is simple, cheap, reliable, and can obtain a syngas of high CO+H2 concentration with sufficient high ratio of H2 to CO, suitable for synthesis of Methane, DME, FT-fuels or alcohol fuels This development work is expected to help for developing an effective and a reliable BTL technology in S&M scales under 200 MW, possibly for biorefinery integration.

  • 16.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Tar/CH4 Reforming by Catalytic Bed Materials in a Biomass Fluidised Bed Gasifier2012In: 20th European Biomass Conference & Exhibition: Proceedings of the International Confernce held in Milano, Italy, 18 - 22 June 2012, 2012Conference paper (Other academic)
    Abstract [en]

    A study on in-bed catalytic material reforming of tar/methane (CH4) has been performed in the 150 kW allothermal biomass gasifier at Mid Sweden University (MIUN). The MIUN gasifier, built for research on synthetic fuel production, is a dual fluidised bed gasifier (DFBG). The syngas for automotive fuels synthesis has a strict specification of impurities. The biggest challenge for biomass fluidised-bed gasification is the reforming of tars and CH4. Internal reforming should be considered before downstream reforming. The MIUN gasifier has a unique design suitable for in-bed tar/CH4 catalytic reforming and continuously internal regeneration of the reactive bed material. The experimental tests are carried out in three cases: 1) basic condition with silica sand (no catalytic activity), 2) calcinated olivine, and 3) Fe-impregnated olivine (10%wtFe/Olivine Catalyst). The measurement results have been evaluated by comparing tar/CH4 content in the syngas from the gasifier operated under different operation conditions. These results in BFB mode have initiated the ongoing investigations of the catalytic effects and regeneration in DFB mode. It can be concluded that the Fe-impregnated olivine showed a surprising low reactivity for tar and CH4 reforming in the BFB model. 

  • 17.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    TAR/CH4 REFORMING BY CATALYTICALLY ACTIVE MATERIALS IN A BIOMASS DUAL FLUIDISED BED GASIFIER 2010In: The second International Symposium on Gasification and Its Application (ISGA 2010), December 5-8, Fukuoka, Japan, 2010Conference paper (Refereed)
    Abstract [en]

    This paper presents a study on the effects of catalytically active materials, before tests in the 150 kW allothermal biomass gasifier at Mid Sweden University (MIUN). The gasifier has been built up in 2008 for research on synthetic fuel production, and is a combination of a circulating fluidised bed (CFB) riser as combustor and a fluidised bed (FB) as steam gasifier. The MIUN gasifier has a unique design suitable for in-built tar/methane (CH4) catalytic reforming. The lifetime of the catalyst can be prolonged using a dual fluidised bed gasifier (DFBG) with continuously internal regeneration of the catalyst. The catalytic effects of 1) basic condition with silica sand (no catalytic activity), 2) commercial catalyst, 3) development metal-catalyst (high surface area support), and 4) olivine catalyst will be evaluated by comparing tar/CH4 content in the syngas from the gasifier operated under different conditions. Silica sand and commercial catalyst can be considered as extremes for comparing the activity of the chosen conditions.

  • 18.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    A technical description of BTL laboratory at Mid Sweden University2007Report (Other academic)
  • 19. He, J H
    et al.
    Wan, H
    He, T
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Research progress on biomass fuel ethanolManuscript (Other (popular science, discussion, etc.))
    Abstract [en]

    Advances of domestic and overseas biomass fuel ethanol is outlined in this paper. Having evaluated its economic, energy, environmental and social benefits, thereafter its importance as a part of Chinese energy strategy had been confirmed. Finally, a feasible scheme for fuel ethanol production from biomass in large scale is suggested, used for reference.

  • 20.
    He, Jie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Techno-economic evaluation of a mechanical pulp mill with gasification2013In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 28, no 3, p. 349-357Article in journal (Refereed)
    Abstract [en]

    Mechanical pulping processes, including thermomechanical pulp (TMP), groundwood (SGW andPGW), and chemithermomechanical pulp (CTMP) processes, each have a very high wood-to-pulp yield. Producing pulp by means of these processes is a prerequisite for paper (such as printing paper and paperboard) grades requiring high printability and stiffness. However, mechanical pulping processes consume a great amount of electricity, which may account for up to 40% of the total pulp production cost.

    In mechanical pulping mills, wood (biomass) residues are commonly utilized for electricity production through an associated combined heat and power (CHP) plant. This techno-economic evaluation deals with the possibility of utilizing a biomass integrated gasification combined cycle (BIGCC) plant in place of the CHP plant.

    Implementing BIGCC in a mechanical pulp production line might greatly improve the overall energy efficiency and cost-effectiveness, especially when more biomass from forest (such as branches and tree tops) is available. When the fibre material that negatively affects pulp properties is utilized as a bioenergy resource, the overall efficiency will be further improved. A TMP+BIGCC mathematical model is developed with ASPEN Plus. By means of modeling, three cases are studied:

    1) adding more forest biomass logging residues in the gasifier,2) adding the reject fibres in the gasifier, and3) decreasing the TMP-specific electricity consumption (SEC) by up to 50%.

    For a TMP+BIGCC mill, the energy supply and consumption are analyzed in comparison with a TMP+CHP mill. The production profits are evaluated.

  • 21.
    He, Jie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Bio-SNG production in a TMP Mill in comparison with BIGCC2014In: Energy Procedia, Elsevier, 2014, Vol. 61, p. 2894-2897Conference paper (Refereed)
    Abstract [en]

    Biorefinery as a concept for polygeneration of various bio-based materials, fuels and chemicals has been more and more attractive. This concept is applied to the thermomechanical pulp (TMP) and paper industry in the present study to evaluate the possibility of co-production of substitute natural gas (SNG), electricity and district heating (DH) in addition to mechanical pulp and paper. In TMP mills, wood and biomass residues are commonly utilized for electricity and steam production through an associated combined heat and power (CHP) plant. This CHP plant is designed to be replaced by a biomass-T o-SNG (BtSNG) plant including an associated heat and power centre. Implementing BtSNG in a mechanical pulp production line might improve the profitability of a TMP mill and also help to commercialize the BtSNG technology by taking into account of some key issues such as, biomass availability, heat utilization etc. A TMP+BtSNG mathematical model is developed with ASPEN Plus.

  • 22.
    He, Jie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Göransson, Kristina
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Simulation of biomass gasification in a dual fluidized bed gasifier2012In: Biomass Conversion and Biorefinery, ISSN 2190-6815, E-ISSN 2190-6823, Vol. 2, no 1, p. 1-10Article in journal (Refereed)
  • 23.
    He, Jie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Research on ethanol synthesis from syngas2008In: Journal of Zhejiang University - Science A, ISSN 1673-565X, Vol. 9, no 5, p. 714-719Article in journal (Refereed)
    Abstract [en]

    It is a very fine substitutable energy technology to synthesize ethanol from biomass-derived syngas. This paper summarized the development of preparing ethanol from syngas, and especially elaborated on the research status of catalysts for the process. Based on the relative researches on the reaction mechanism, structure and performance of the catalysts, the optimumdesign of catalysts with high activity was presented in this review, which set the theoretical and application foundation for the industrial production of ethanol from syngas.

  • 24.
    He, Jie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Techno-economic evaluation of thermo-chemical biomass-to-ethanol2011In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 88, no 4, p. 1224-1232Article in journal (Refereed)
    Abstract [en]

    Bio-ethanol has received considerable attention as a basic chemical and fuel additive. Bio-ethanol is presently produced from sugar/starch materials, but can also be produced from lignocellulosic biomass via hydrolysis-fermentation route or thermo-chemical route. In terms of thermo-chemical route, a few pilot plants ranging from 0.3 to 67 MW have been built and operated for alcohols synthesis. However, commercial success has not been found. In order to realize cost-competitive commercial ethanol production from lignocellulosic biomass through thermo-chemical pathway, a techno-economic analysis needs to be done. In this paper, a thermo-chemical process is designed, simulated and optimized mainly with ASPEN Plus. The techno-economic assessment is made in terms of ethanol yield, synthesis selectivity, carbon and CO conversion efficiencies, and ethanol production cost. Calculated results show that major contributions to the production cost are from biomass feedstock and syngas cleaning. A biomass-to-ethanol plant should be built around 200 MW. Cost-competitive ethanol production can be realized with efficient equipments, optimized operation, cost-effective syngas cleaning technology, inexpensive raw material with low pretreatment cost, high performance catalysts, off-gas and methanol recycling, optimal systematic configuration and heat integration, and high value byproduct.

  • 25.
    He, Qiao
    et al.
    Huazhong University of Science and Technology, Wuhan, 430074, China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    A study on latent heat storage exchangers with the high-temperature phase-change material2001In: International Journal of Energy Research, ISSN 0363-907X, Vol. 25, no 4, p. 331-341Article in journal (Refereed)
    Abstract [en]

    This paper presents a theoretical analysis and an experimental test on a shell-and-tube latent heat storage exchanger. The heat exchanger is used to recover high temperature waste heat from industrial furnaces and off-peak electricity. It can also be integrated into a renewable energy system as an energy storage component. A mathematical model describing the unsteady freezing problem coupled with forced convection is solved numerically to predict the performance of the heat exchanger. It provides a basis for optimum design of the heat exchanger. The experimental study on the heat exchanger is carried out under various operating conditions. Effects of various parameters, such as the inlet temperature, the mass flow rate, the thickness of the phase change material and the length of the pipes, on the heat transfer performance of the unit are discussed by combining with theoretical prediction. Criterion for analyzing and evaluating the performance of heat exchanger is also proposed.

  • 26.
    Henschel, Till
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    A study on the pyrolysis behaviour of different biomass fuels using thermogravimetry and online gas analysis2016In: European Biomass Conference and Exhibition Proceedings, ETA-Florence Renewable Energies , 2016, Vol. 24thEUBCE, no 24thEUBCE, p. 1290-1293Conference paper (Refereed)
    Abstract [en]

    Fuel availability and flexibility are important issues for biomass-based heat/power and advanced biofuel plants. The physical and chemical properties of biomass feedstocks vary from one to others to a great degree, which must be taken care of for the reactor design/operation, system optimization and blend feedstock application. In this work, the biomass property is evaluated based on pyrolysis behavior of biomass fuels by means of TGA and online gas analysis. Wood, pine bark, peat, straw, black liquor and microalgae are chosen as the biomass feedstocks for the pyrolysis study. The measurement results show high volatile content for algae and black liquor (around 85%) and low volatile content for pine bark and peat (around 69%). Differently from woody biomass, the DTG curve of straw has a single dominant peak at much lower temperature, which suggests a dominant component of hemicellulose in biomass, while algae and peat have a broader temperature specturm of devolatilization but much lower peak temperature. CO2 is released first and H2 later in the pyrolysis process for all biomass feedstocks, whileas the peak of CO formation follows CO2 formation trend for most feedstocks used, except for peat and pine bark which give a peak later at high temperature. This indicates secondary reactions of tar cracking, steam reforming and char gasification.

  • 27.
    Hu, Junhao
    et al.
    Huazhong Univ Sci & Technol, Peoples R China.
    Shao, Jingai
    Huazhong Univ Sci & Technol, Peoples R China.
    Yang, Haiping
    Huazhong Univ Sci & Technol, Peoples R China.
    Lin, Guiying
    Huazhong Univ Sci & Technol, Peoples R China.
    Chen, Yingquan
    Huazhong Univ Sci & Technol, Peoples R China.
    Wang, Xianhua
    Huazhong Univ Sci & Technol, Peoples R China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Chen, Hanping
    Huazhong Univ Sci & Technol, Peoples R China.
    Co-gasification of coal and biomass: Synergy, characterization and reactivity of the residual char2017In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 244, p. 1-7Article in journal (Refereed)
    Abstract [en]

    The synergy effect between coal and biomass in their co-gasification was studied in a vertical fixed bed reactor, and the physic-chemical structural characteristics and gasification reactivity of the residual char obtained from co-gasification were also investigated. The results shows that, conversion of the residual char and tar into gas is enhanced due to the synergy effect between coal and biomass. The physical structure of residual char shows more pore on coal char when more biomass is added in the co-gasification. The migration of inorganic elements between coal and biomass was found, the formation and competitive role of K2SiO3, KAlSiO4, and Ca3Al2(SiO4)(3) is a mechanism behind the synergy. The graphization degree is enhanced but size of graphite crystallite in the residual char decreases with biomass blending ratio increasing. TGA results strongly suggest the big difference in the reactivity of chars derived from coal and biomass in spite of influence from co-gasification.

  • 28. Jensen, A
    et al.
    Åsman, S
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Pyrolys av Biobränsle2000Report (Other (popular science, discussion, etc.))
  • 29.
    Jiang, X.
    et al.
    School of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China.
    Song, X.
    School of Forestry, Central South University of Forestry and Technology, Changsha 410004, China.
    Chen, Y.
    School of Forestry, Central South University of Forestry and Technology, Changsha 410004, China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Research on biogas production potential of aquatic plants2014In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 69, p. 97-102Article in journal (Refereed)
    Abstract [en]

    This paper is to explore the biogas production potential of wetland aquatic biomass plants. 7 species of wetland aquatic biomass plants are used in the study, which include 4 plants with more fiber carbohydrate, Acorus calamus Linn, Typha orientalis Presl, Pontederia cordata and Canna indica, and 3 plants with more starch carbohydrate, Colocasia tonoimo Nakai, Thalia dealbata and Hydrocotyle vulgaris. In the experiment, these plants were treated by anaerobic fermentation in batch mode at 37°C. The results show that the anaerobic biogas production potential (ABP, mL·g-1VS) of aquatic biomass plants is different for different components content (%TS). The correlation between ABP and hemicellulose content is significant and negative (R=-0.784, 0.01<p<0.05), and the correlation between ABP and starch carbohydrate content is significant and positive (R=0.767, 0.01<p<0.05). The multiple stepwise regression equation with cross variable can roughly meet the statistical model to reflect the coeffect of hemicellulose, cellulose, starch carbohydrate and lignin on ABP of aquatic biomass plants, y=238.62+2.60x1+28.55x2-2.08x2x3+12.67x3, (Adj-R2=0.962, p(intercept)=0.034, p(x1)=0.101, p(x2)=0.036, p(x2x3)=0.066, p(x3)=0.031, p=0.025, SD=9.95), y represents ABP (mLg-1VS), x1, x2 and x3 represents the cellulose, lignin and starch carbohydrate content (%TS) respectively.

  • 30.
    Liu, Huihui
    et al.
    Huazhong Univ Sci & Technol, Wuhan, Hubei, Peoples R China.
    Chen, Yingquan
    Huazhong Univ Sci & Technol, Wuhan, Hubei, Peoples R China.
    Yang, Haiping
    Huazhong Univ Sci & Technol, Wuhan, Hubei, Peoples R China.
    Gentili, Francesco G.
    Swedish Univ Agr Sci, Umeå.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Wang, Xianhua
    Huazhong Univ Sci & Technol, Wuhan, Hubei, Peoples R China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Chen, Hanping
    Huazhong Univ Sci & Technol, Wuhan, Hubei, Peoples R China.
    Hydrothermal carbonization of natural microalgae containing a high ash content2019In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 249, p. 441-448Article in journal (Refereed)
    Abstract [en]

    The potential to convert natural microalgae (Scenedesmus) into solid fuels by hydrothermal carbonization (HTC) was evaluated. The deashing microalgae (DA) were obtained by acid-washing natural microalgae (NM) with HCl. The deashing efficiency was high from 44.66% for NM to 14.45% for DA. HTC carried out at temperature in the range from 180 to 260 degrees C with this two types feedstock (i.e. NM and DA). The results showed that DA-derived hydrochars had good physicochemical and fuel properties compared with that of NM-derived hydrochars. HTC process of DA was mainly based on polymerization, and the hydrolysis process was short. The hydrochars obtained from DA at 220 degrees C (HC-D220) had the highest value of 51.86% with a carbon content and fixed carbon content 1.15 and 1.33 times, respectively, greater than that of DA. The high heating value (HHV) of HC-D220 reached 26.64 MJ/kg which is equivalent to medium-high calorific coal. The thermogravimetric analysis (TG) demonstrated that the hydrochars derived from DA have good combustion properties with stable at high temperature zones. They can easily mix with coal or replace coal in combustion application. The results of this study revealed that natural microalgae can be utilized by hydrothermal carbonization to generate renewable fuel resources.

  • 31.
    Tang, Yu-xing
    et al.
    Zhejiang Univ, Hangzhou, Peoples R China.
    Luo, Zhong-yang
    Zhejiang Univ, Hangzhou, Peoples R China.
    Yu, Chun-jiang
    Zhejiang Univ, Hangzhou, Peoples R China.
    Cen, Jian-meng
    Zhejiang Univ, Hangzhou, Peoples R China.
    Chen, Qian-yuan
    Fudan Univ, Shanghai, Peoples R China; Minist Environm & Ecol, State Environm Protect Key Lab Radiat Monitoring, Hangzhou, Zhejiang, Peoples R China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Determination of biomass-coal blending ratio by C-14 measurement in co-firing flue gas2019In: Journal Of Zhejiang University-Science A, ISSN 1673-565X, Vol. 20, no 7, p. 475-486Article in journal (Refereed)
    Abstract [en]

    To verify the feasibility of using radiocarbon detection for the measurement of the biomass-coal blending ratio in co-firing heat and power plants, C-14 activity detection technology that uses benzene synthesis as the sample preparation method and a liquid scintillation counter as the detection instrument was studied. A benzene synthesis system was built to enrich carbon in the combustion flue gas in the form of benzene. The benzene sample was mixed with scintillator (butyl-PBD) and C-14 activity was measured using a liquid scintillation counter (Quantulus 1220). Three kinds of coal and six kinds of biomass were tested repeatedly. The measured C-14 activity was 0.3365 DPM/gC in Zhundong lignite, 0.2701 DPM/gC in Shenmu bitumite, and 0.3060 DPM/gC in Changzhi anthracite. These values were much higher than the instrument background activity. For the co-fired experiment, we used groups with biomass ratios (based on the carbon) of 6.51%, 12.95%, and 20.75%. A modified empirical expression to determine the biomass, coal blending ratio based on the C-14 activity measured in the co-firing flue gas, was proposed by analyzing and verifying measurement accuracy. From the C-14 measurements of the co-fired samples, the corresponding estimated biomass ratios were (5.540.48)%, (12.310.67)%, and (19.490.90)%. The absolute measurement error was around 1% for a typical biomass-coal co-firing application.

  • 32.
    Tran, Khanh-Quang
    et al.
    Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim, Norway.
    Klemsdal, Aksel Junge
    Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim, Norway.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Sandquist, Judit
    SINTEF Energy Research, Trondheim, Norway.
    Wang, Liang
    SINTEF Energy Research, Trondheim, Norway.
    Skreiberg, Øyvind
    SINTEF Energy Research, Trondheim, Norway.
    Fast Hydrothermal Liquefaction of Native and Torrefied Wood2017In: Energy Procedia, Elsevier, 2017, Vol. 105, p. 218-223Conference paper (Refereed)
    Abstract [en]

    The work presented in this paper aimed to examine the effect of heating rate on the bio-crude yield of wood hydrothermal liquefaction. Three different heating methods were developed, resulting in heating rates ranging from 66°C/min to 179°C/min. The experiments were conducted using Norway spruce wood as feedstock at an operation temperature of 350°C and with a total reaction time of 15 minutes. The bio-crude product was collected and separated using dichloromethane (DCM) as solvent and a centrifugal separator. The results confirm that heating rate has a clear positive effect on the bio-crude oil yield, increasing from 18.9 wt% for the lower heating rate of 66°C/min to 35.8 wt% for the higher heating rate of 179°C/min. It is also shown that the effect of feedstock pre-treatment via torrefaction on the bio-crude yield is negative.

  • 33.
    Wennan, Zhang
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Coal gasification - for LKAB pelletizing furnaces2007Report (Other academic)
  • 34.
    Yang, Haiping
    et al.
    Huazhong University of Science and Technology, Wuhan, China.
    Wang, Daqian
    Huazhong University of Science and Technology, Wuhan, China.
    Li, Bin
    Huazhong University of Science and Technology, Wuhan, China.
    Zeng, Zhiwei
    Huazhong University of Science and Technology, Wuhan, China.
    Qu, Lei
    Huazhong University of Science and Technology, Wuhan, China.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Chen, Hanping
    Huazhong University of Science and Technology, Wuhan, China.
    Effects of potassium salts loading on calcium oxide on the hydrogen production from pyrolysis-gasification of biomass2018In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 249, p. 744-750Article in journal (Refereed)
    Abstract [en]

    The effects of potassium (K) salts loading on CaO on the H2 production from pyrolysis-gasification of wheat straw were investigated. The loading of 0.25 wt% KCl could significantly enhance the CO2 absorption capability of CaO. The CO2 concentration in the product gas decreased sharply from 20.83 to 11.70 vol%, and the H2 concentration increased from 48.2 to 55.5 vol%. While the loading of 0.25 wt% K2CO3/K2SO4 inhibited the enhancing effect of CaO. Further increasing the loading of KCl on CaO, the CO2 absorption of CaO declined, but the catalytic effect of KCl on the gasification process was promoted. The loading of 0.25 wt% KCl on CaO significantly improved the cyclic performance of CaO during the pyrolysis-gasification process. Higher H2 concentration and more CO2 absorbed by CaO were obtained with the loading of 0.25 wt% KCl even after 5 cycles compared with those of pure CaO in the first cycle. 

  • 35. Yu, C
    et al.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Modeling potassium release in biomass pyrolysis2008In: Progress in thermochemical biomass conversion: [based on papers delivered to the Fifth International Conference on Thermochemical Biomass Conversion], Oxford: Blackwell science , 2008, p. 1107-1115Conference paper (Refereed)
    Abstract [en]

    Alkali compound emission during biomass thermochemical conversion gives rise to a number of problems such as agglomeration, slag, fouling and metal corrosion in the conversion process system. Understanding the behaviour of alkali emission from biomass fuels is important to solve these problems. In this work, a study focused on the potassium compound release in biomass pyrolysis is carried out. The transformation of the element, K, is interpreted based on literature and the present study. A mathematic model of the potassium compounds emitting from biomass during pyrolysis is proposed. The different existing forms of potassium in biomass, the chemical equilibrium of the compounds at the pyrolytic environment and the potassium compound release due to vaporization at high temperature are taken into account in the model. The result of the mathematic model provides an understanding of the alkali compound release in biomass pyrolysis and the effects of the pyrolytic temperature, the fuel composition and residence time on the release process.

  • 36. Yu, C
    et al.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Cen, K
    A modelling study on cellulose particle pyrolysis under fluidized-bed conditions.2008In: Progress in thermochemical biomass conversion: [based on papers delivered to the Fifth International Conference on Thermochemical Biomass Conversion], Oxford: Blackwell science , 2008, p. 1091-1106Conference paper (Refereed)
    Abstract [en]

    To study biomass pyrolysis processes, a numerical model is developed in this work focusing on the cellulose constituent. A single cellulose particle is supposed to experience pyrolysis at a fairly high heating rate in the case of typical fluidized bed conditions. The model involves the pyrolytic kinetic scheme and the detailed heat and mass transfers caused by radiation, conduction, diffusion and convection with respect to the solid, liquid and gas products from pyrolysis. From the solution of the model, the central role of the reaction heat versus a slow heat supply through the particle is identified. The dynamic characteristic of the pyrolysis and the evolutions of the internal pressure and the flow of the products are analyzed quantitatively. Computation of the model shows the importance of particle permeability, whereas the liquid phase of active cellulose and inter-particle secondary reaction of volatile play a negligible role during the pyrolysis under a typical fluidized bed conditions both for small and large particles. Various predictions by the model provide a good understanding of the complex process of biomass pyrolysis, which can be useful for applications of thermochemical conversions of biomass.

  • 37. Yu, C.
    et al.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Cen, K.
    A study on kinetic model for cellulose pyrolysis modeling2000In: Renewable energy : renewables, the energy for the 21st century: Part II, 2000, p. 1369-1372Conference paper (Refereed)
  • 38. Yu, C.
    et al.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Cen, K.
    PROCESS MODELING OF A CELLULOSE PARTICLE DURING PYROLYSIS2000In: 1st World Conference on Biomass for Energy and Industry: part II, 2000, p. 1848-1851Conference paper (Other scientific)
    Abstract [en]

    To study biomass pyrolysis process, a mathematic model is developed in this work focusing on the cellulose constituent. A single cellulose particle is supposed to experience pyrolysis once exposed to an environment of 800 C°. The model involves the pyrolytic kinetic scheme and the detailed heat and mass transfers caused by radiation, conduction, diffusion and convection with respect to the solid, liquid and gas products from pyrolysis. Based on the model computation results, the heat and mass transfer limits to the pyrolysis are discussed. The central role of the pyrolytic reaction heat versus a slow heat supply through the particle is identified. Various predictions by the model provide a good understanding of the complex process of biomass pyrolysis, which can be useful for applications of thermochemical conversions of biomass.

  • 39.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    A review on biofuels for transportation2006In: Asia Biofuels Conference & Expo IV, 2006, Beijing., 2006Conference paper (Other scientific)
    Abstract [en]

    Energy use in the transport sector is heavily dependent on crude oil which is running out in a limited time. Under the pressure of oil dependency and climate change, the possibility of producing transportation fuels from biomass and wastes has been a more and more attractive subject. The first generation of biofuels for transportation, such as bioethanol, biodiesel and biogas produced from agricultural activities have been successfully introduced into the transport market in a number of countries. From the viewpoint of fuel potential, economics, environment, land use, water use and chemical fertilizer use, there is a strong preference for the use of woody biomass and various forest/agricultural residues as the feedstock. Thus, the production of second generation of biofuels i.e. synthetic transportation fuels such as methanol, DME, FT-diesel and hydrogen through biomass gasification seems promising. This paper is trying to review the present market of the first generation of bio-automotive fuels and the technology development of the second generation of bio-automotive fuels. It can be concluded that the second generation of bio-automotive fuels is on the way to a breakthrough in the transport markets of industrial countries especially for those countries with a strong forest industry. The first generation will remain as favourable bio-automotive fuels in the developing countries.

  • 40.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Automotive fuels from biomass via gasification2010In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 91, no 8, p. 866-876Article in journal (Refereed)
    Abstract [en]

    There exists already a market of bioautomotive fuels i.e. bioethanol and biodiesel produced from food crops in many countries. From the viewpoint of economics, environment, land use, water use and chemical fertilizer use, however, there is a strong preference for the use of woody biomass and various forest/agricultural residues as the feedstock. Thus, the production of 2nd generation of bioautomotive fuels i.e. synthetic fuels such as methanol, ethanol, DME, FT-diesel, SNG and hydrogen through biomass gasification seems promising. The technology of producing synthetic fuels are well established based on fossil fuels. For biomass, however, it is fairly new and the technology is under development. Starting from the present market of the 1st generation of bio-automotive fuels, this paper is trying to review the technology development of the 2nd generation bio-automotive fuels. The production of syngas is emphasized which suggests appropriate gasifier design for a high quality syngas production. A number of bio-automotive fuel demonstration plant will be presented, which gives the state of the art in the development of BTS (biomass to synthetic fuels) technologies. It can be concluded that the 2nd generation bio-automotive fuels is on the way to a breakthrough in the transport markets of industrial countries especially for those countries with a strong forest industry.

  • 41.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Bioethanol market and perspective2007Report (Other academic)
  • 42.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Biomass pellet perspective and market2007Report (Other academic)
  • 43.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Peat perspective and market2007Report (Other academic)
  • 44.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    PROCESS SIMULATION OF CIRCULATING FLUIDIZED BEDS - mid term assessment report 2000Report (Other scientific)
  • 45.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    PROCESS SIMULATION OF CIRCULATING FLUIDIZED BEDS - yearly report1999Report (Other scientific)
  • 46.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    PROCESS SIMULATION OF CIRCULATING FLUIDIZED BEDS - yearly report: reporting the JOR3CT980306 project of 4th EU-framework Programme2000Report (Other academic)
  • 47.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    TRANSPORTATION FUELS FROM BIOMASS VIA GASIFICATION: 2nd World Conference and Exhibition on Biomass for Energy and Industry, May 2004, Rome, Italy2004Conference paper (Other scientific)
    Abstract [en]

    There exists already a market of transportation fuels i.e. bioethanol and biodiesel produced from food crops in several countries. From the viewpoint of economics, environment, land use, water use and chemical fertilizer use, however, there is a strong preference for the use of woody biomass and various forest/agricultural residues as the feedstock. Thus, the production of transportation fuels through biomass gasification seems the most promising. The technology of producing liquid fuels such as methanol and FT-diesel is well established based on fossil fuels. For biomass, however, it is fairly new. This paper critically reviews a number of transportation fuels such as methanol, DME, FT-fuels etc. with respect to four criteria: efficiency, economy, environmental impact and end use with emphasis on well-to-wheel efficiency. The production of syngas required is discussed which suggests appropriate gasifier design for a high quality syngas production. It is supposed that ethanol is the best choice to substitute gasoline while FT-diesel is the best choice to substitute diesel.

  • 48.
    Zhang, Wennan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Dai, X
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Wu, C
    Further test on the Sanya 6MW biomass CFB gasifier2004In: 2nd World Conference and Exhibition on Biomass for Energy, Industry and Climate Protection. Rome, Italy, 10 - 14 May 2004, 2004Conference paper (Other scientific)
    Abstract [en]

    Following a preliminary test on the 6 MW Sanya biomass CFB gasifier (reported in the last conference at Amsterdam), a further test has been carried out focusing on the use of in-bed dolomite in order to reduce the tar content in the product gas. The gas composition and tar contents in the product gas at different temperatures were measured and analyzed. The results show that there is no big difference between two cases with and without dolomite at low temperature of 700C. However, at high temperature of 900C, the tar content was reduced significantly by the addition of in-bed dolomite. Temperature has a strong effect on the efficiency of dolomite catalyst

  • 49.
    Zhang, Wennan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Dai, X.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Wu, C.
    Luo, X.
    A PRELIMINARY TEST ON AN INDUSTRIAL BIOMASS CFB GASIFIER 2002In: 12th European Biomass Conference: Vol. 1, 2002, p. 745-748Conference paper (Other scientific)
    Abstract [en]

    A test was carried out on an 6 MW industrial biomass atmospheric CFB gasifier in a power plant. The gas composition, NH3 and tar contents in the product gas at different temperatures were measured and analyzed. Ash (char in the present case) analysis was also made to make mass balance of chemical element in solid and gas phases during gasification based on Si balance analysis. The measurement results show that a gas productivity of 2 Nm3/kg (daf biomass) with gas LHV of 5MJ/Nm3 can be achieved at 750℃.The conversion of fuel-bound nitrogen (FBN) to NH3 ranges from 6 wt% to 70 wt% depending on temperature. Tar content in the product gas ranges from 2.5 to 16.7 g/m3. Small fractions of H, O, N, Cl and S contents in fuel remain in the ash while most of mineral metal element remains in the ash.

  • 50.
    Zhang, Wennan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Forsman, B.
    Söderlind, U.
    Biofuels in Sweden2005In: Proceedings of the 7th World Congress on Recovery Recycling and Reintegration, 2005Conference paper (Other scientific)
    Abstract [en]

    Biomass residual from forest has been utilized in a large scale in Sweden after full speed development over the past decade, which contributes about 20% of the total energy consumption. This is a big event for an industrial country to shift fossil fuel-based society to a sustainable society. The well established biofuel market in Sweden is, in principle, attributed to the good synergy of a strong forest industry with the energy sector, to a good district heating system, and to a favorable tax system. In this paper, the authors are trying to present a picture of how biomass residual is shaping the Swedish energy system in the past and for the future. The production of heat, electricity and transportation fuels will be discussed. A number of critic points associated to biofuel potential, economy, environmental impact, end-use, as well as to biomass conversion technologies such as combustion, gasification and biological processes will be discussed. The advances of research and technology development in Sweden will be overviewed. Swedish bioenergy industry shows a good example in the world regarding biomass residual utilization as a renewable energy. The practices and experiences might be useful to other countries.

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