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  • 1.
    Antonopoulou, Io
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Spanopoulos, Athanasios
    Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 5 Iroon Polytechniou Str, Zografou Campus, Athens, Greece.
    Matsakas, Leonidas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Single cell oil and ethanol production by the oleaginous yeast Trichosporon fermentans utilizing dried sweet sorghum stalks2020Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 146, s. 1609-1617Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ability of the oleaginous yeast Trichosporon fermentans to efficiently produce lipids when cultivated in dried sweet sorghum was evaluated. First, lipid production was evaluated in synthetic media mimicking the composition of sweet sorghum stalks and optimized based on the nitrogen source and C: N ratio. Under optimum conditions, the lipid production reached 3.66 g/L with 21.91% w/w lipid content by using a mixture of sucrose, glucose and fructose and peptone at C: N ratio 160. Cultivation on pre-saccharified sweet sorghum stalks offered 1.97 g/L, while it was found that sweet sorghum stalks can support yeast growth and lipid production without the need for external nitrogen source addition. At an attempt to increase the carbon source concentration for optimizing lipid production, the Crabtree effect was observed in T. fermentans. To this end, the yeast was evaluated for its potential to produce ethanol under anaerobic conditions in synthetic media and sweet sorghum. The ethanol concentration at 100 g/L glucose was 40.31 g/L, while utilizing sweet sorghum by adding a distinct saccharification step and external nitrogen source offered ethanol concentration equal to 23.5 g/L. To the authors’ knowledge, this is the first time that the Crabtree effect is observed in T. fermentans.

  • 2.
    Gehlin, Signhild
    et al.
    Luleå tekniska universitet.
    Hellström, Göran
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    The influence of the thermosiphon effect on the thermal response test2003Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 28, nr 14, s. 2239-2254Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The issue of natural and forced groundwater movements, and its effect on the performance of ground heat exchangers is of great importance for the design and sizing of borehole thermal energy systems (BTESs). In Scandinavia groundwater filled boreholes in hard rock are commonly used. In such boreholes one or more intersecting fractures provide a path for groundwater flow between the borehole and the surrounding rock. An enhanced heat transport then occurs due to the induced convective water flow, driven by the volumetric expansion of heated water. Warm groundwater leaves through fractures in the upper part of the borehole while groundwater of ambient temperature enters the borehole through fractures at larger depths. This temperature driven flow is referred to as thermosiphon, and may cause considerable increase in the heat transport from groundwater filled boreholes. The thermosiphon effect is connected to thermal response tests, where the effective ground thermal conductivity is enhanced by this convective transport. Strong thermosiphon effects have frequently been observed in field measurements. The character of this effect is similar to that of artesian flow through boreholes.

  • 3. Gehlin, Signild
    et al.
    Hellström, Göran
    Influence on thermal response test by groundwater flow in vertical fractures in hard rock2003Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 28, nr 14, s. 2221-2238Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper different approaches to groundwater flow and its effect in the vicinity of a borehole ground heat exchanger are discussed. The common assumption that groundwater flow in hard rock may be modelled as a homogeneous flow in a medium with an effective porosity is confronted and models for heat transfer due to groundwater flow in fractures and fracture zones are presented especially from a thermal response test point of view. The results indicate that groundwater flow in fractures even at relatively low specific flow rates may cause significantly enhanced heat transfer, although a continuum approach with the same basic assumptions would suggest otherwise.

  • 4.
    Gustafsson, Anna-Maria
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Westerlund, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Heat extraction thermal response test in groundwater-filled borehole heat exchanger: Investigation of the borehole thermal resistance2011Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 36, nr 9, s. 2388-2394Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In groundwater-filled borehole heat exchangers (BHEs) convective flow influences the heat transfer in the borehole. During heat extraction thermal response tests (TRTs) the effect of the changing convective flow is more dominant than during heat injection tests. Water is heaviest around 4 °C and when exceeding this temperature during the test, the convective flow is stopped and restarted in the opposite direction resulting in a higher borehole thermal resistance during that time. Just before 0 °C the convective flow is the largest resulting in a much lower borehole thermal resistance. Finally, during the freezing period phase change energy is released and material parameters change as water is transformed into ice, resulting in a slightly higher borehole resistance than at a borehole water temperature of 0 °C. The changes in borehole thermal resistance are too large for ordinary analysis methods of thermal response tests to work. Instead another method is introduced where the borehole thermal resistance is allowed to change between different time intervals. A simple 1D model of the borehole is used, which is matched to give a similar mean fluid temperature curve as the measured one while keeping the bedrock thermal conductivity constant during the whole test. This method is more time-consuming than ordinary TRT analyses but gives a good result in showing how the borehole thermal resistance changes. Also, a CFD-model with a section of a simplified borehole was used to further study the effect of convection and phase change while the temperature was decreased below freezing point. The test and the model show similar results with large variations in the borehole thermal resistance. If the knowledge of changing borehole thermal resistance was used together with a design program including the heat pump and its efficiency, a better BHE system design would be possible.

  • 5.
    Gustafsson, Anna-Maria
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Westerlund, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Multi-injection rate thermal response test in groundwater filled borehole heat exchanger2010Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 35, nr 5, s. 1061-1070Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During a thermal response test (TRT) or during operation of a borehole heat exchanger (BHE) system, a temperature gradient in and around the borehole is achieved. This causes convective flow in the groundwater due to density differences. In groundwater filled BHE the convective heat flow influences the heat transport in the borehole system. The size of the influence depends on the injection rate used, which changes during the year for normal BHE systems. Multi-injection rate TRT (MIR TRT) may be used as a method to detect the convective heat influence and to examine the effect on the BHE thermal transport parameters. It was shown that MIR TRT constitutes a valuable method to detect fractured bedrock and to examine the effect of different heat injection rates. For boreholes located in solid bedrock only the borehole thermal resistance was influenced by the convective flow. An increase in heat injection rate resulted in a decrease in resistance. It was shown that the length of the collector did not affect the result. For the fractured bedrock the effective bedrock conductivity was also affected, an increase in heat injection rate resulted in a higher effective bedrock thermal conductivity.

  • 6.
    Kharseh, Mohamad
    et al.
    Qatar University, Mechanical & Industrial Engineering Department, Doha.
    Altorkmany, Lobna
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten. Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Al-Khawaja, Mohammed
    Qatar University, Mechanical & Industrial Engineering Department, Doha.
    Hassani, Ferri
    Department of Mining Metals and Materials Engineering, McGill University, H3A 2A7, Montreal.
    Analysis of the effect of global climate change on ground source heat pump systems in different climate categories2015Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 78, s. 219-225Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ground source heat pump (GSHP) systems exhibit high thermal performance. Consequently, they are increasingly used to heat and cool buildings. The thermal performance of GSHP systems strongly depends on the operation ground temperature and thermal quality of the building envelope (TQBE). The operation ground temperature is a function of mean annual air temperature and annual thermal load of the building. The thermal load depends on the TQBE and outside temperature. Given that ongoing global climate change (GCC) affects air temperatures, it also affects the performance of GSHP systems. The magnitude of this impact on a given GSHP system strongly depends on local weather conditions and the TQBE.The overall aim of the current study is to investigate the impact of GCC on the performance of GSHP systems in different climate. To achieve this aim, three cities located in three climate categories were considered: Stockholm, Sweden (cold), Istanbul, Turkey (mild), and Doha, Qatar (hot). In each city, two buildings were modeled. One was built according to current local building regulations, while the other was built to have a TQBE lower than the standard TQBE. Simulations were run for present (2014) and future (projected for 2050) outdoor designing conditions.

  • 7.
    Kharseh, Mohamad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Altorkmany, Lobna
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Global warming’s impact on the performance of GSHP2011Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 36, nr 5, s. 1485-1491Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Since heating and cooling systems of buildings consume 30e50% of the global energy consumption, increased efficiency of such systems means a considerable reduction in energy consumption. Ground source heat pumps (GSHP) are likely to play a central role in achieving this goal due to their high energy efficient performance. The efficiency of GSHP depends on the ground temperature, heating and cooling demands, and the distribution of heating and cooling over the year. However, all of these are affected by the ongoing climatic change. Consequently, global warming has direct effects on the GSHP performance.Within the framework of current study, heating and cooling demands of a reference building were calculated for different global warming scenarios in different climates i.e. cold, mild and hot climate. The prime energy required to drive the GSHP system is compared for each scenario and two configurations of ground heat exchangers. Current study shows that the ongoing climatic change has significant impact on GSHP systems.

  • 8.
    Mesfun, Sennai
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Sanchez, Daniel L.
    Carnegie Institution for Science, Department of Global Ecology.
    Leduc, Sylvain
    International Institute for Applied Systems Analysis (IIASA).
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Biberacher, Markus
    Research Studios Austria (RSA), Studio iSPACE.
    Kraxner, Florian
    International Institute for Applied Systems Analysis (IIASA).
    Power-to-gas and power-to-liquid for managing renewable electricity intermittency in the Alpine Region2017Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 107, s. 361-372Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 9.
    Möllersten, Kenneth
    et al.
    Luleå tekniska universitet.
    Gao, Lin
    Luleå tekniska universitet.
    Yan, Jinyue
    Efficient energy systems with CO2 capture and storage from renewable biomass in pulp and paper mills2004Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 29, nr 9, s. 1583-1598Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper investigates the impact of combining CO2 capture and storage with alternative systems for biomass-based combined heat and power production (CHP) in Kraft pulp and paper mills. We compare heat, power, and CO2 balances of systems with alternative configurations of the CHP and CO2-capture systems. Because the captured CO2 comes from renewable biomass, the studied systems yield negative CO2 emissions. It is shown that pulp mills and integrated pulp and paper mills have the potential to become net exporters of biomass-based electricity while at the same time removing CO2 from the atmosphere on a net basis. The study shows that that the overall best CO2 abatement is achieved when CO2 capture is carried out within a biomass integrated gasifier with combined cycle where the syngas undergoes a CO-shift reaction. This configuration combines efficient energy conversion with a high CO2 capture efficiency. Furthermore, cost curves are constructed, which show how the cost of CO2 capture and storage in pulp and paper mills depends on system configuration and the CO2 transportation distance.

  • 10.
    Nwachukwu, Chinedu M
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Toffolo, Andrea
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Biomass-based gas use in Swedish iron and steel industry: Supply chain and process integration considerations2020Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 146, s. 2797-2811Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Substitution of fossil gaseous fuels with biomass-based gases is of interest to the iron and steel industry due to its role in the mitigation of anthropogenic CO2emissions. In switching from fossil fuels to biomass-based gases, a systems analysis of the full value chain from biomass supply to the production and supply of final gas products becomes crucial. This study uses process and heat integration methods in combination with a supply chain evaluation to analyse full value chains of biomass-based gases for fossil gas replacement within the iron and steel industry. The study is carried out as a specific case study in order to understand the implications of utilizing bio-syngas/bio-SNG as heating fuels in iron- and steel-making, and to provide insights into the most sensitive parameters involved in fuel switching. The results show a significant cost difference in the fuel production of the two gas products owing to higher capital and biomass use in the bio-SNG value chain option. When tested for sensitivity, biomass price, transportation distance, and capital costs show the most impact on fuel production costs across all options studied. Trade-offs associated with process integration, plant localisation, feedstock availability and supply were found to varying extents.

  • 11.
    Patel, Alok
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), Roorkee, Uttarakhand, India.
    Pruthi, Vikas
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), Roorkee, Uttarakhand, India;iofuel Laboratory, Centre for Transportation Systems, Indian Institute of Technology Roorkee (IIT-R), Roorkee, Uttarakhand, India.
    Pruthi, Parul A.
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), Roorkee, Uttarakhand, India.
    Innovative screening approach for the identification of triacylglycerol accumulating oleaginous strains2019Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 135, s. 936-944Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Currently, triacylglycerides (TAG) accumulation in the form of lipid droplets (LDs) in oleaginous microorganisms is of immense importance due to their ability to get transesterified into value-added products in the form of biodiesel. Hence, in order to search for oleaginous microorganisms having high lipid content among a wide range of samples from different niches, there is a compulsive need to develop simple, reliable and rapid methods for screening of TAG accumulating strains. Conventional methods require multistep processes for the isolation, cultivation, extraction and estimation of lipids to identify oleagenic strains. To overcome these challenges, we are proposing an easy, live cellimaging technique for the estimation of lipids via visualization of TAG accumulation in probable strains at the single cell level that gives real-time monitoring of intracellular lipid accumulation in yeasts. In this screening technique, only 100 μl of specific neutral lipid accumulating medium was used to grow the isolated culture in the microtiter plate. The harvested cells were stained with LipidTOX™ Green and visualized by a LED based digital inverted fluorescence microscope. Among 446 yeast colonies screened, maximum lipid producing yeast strains Rhodosporidium kratochvilovae HIMPA1 and Rhodotorula minuta,having supersized lipid body of 5.05 ± 0.87 μm and 4.46 ± 0.61 μm, respectively, were identified as potential candidates for biodiesel production. To the best of our knowledge, this is the first report of using LipidTOX™ Green for the staining of lipid droplets present in yeast cells as per the literature.

  • 12.
    Svanberg, Martin
    et al.
    SSPA SWEDEN AB.
    Finnsgård, Christian
    SSPA SWEDEN AB.
    Flodén, Jonas
    Department of Business Administration, School of Business, Economics and Law, University of Gothenburg.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Analyzing animal waste-to-energy supply chains: The case of horse manure2018Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 129B, s. 830-837Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To reduce human impact upon the environment, a transition from fossil to renewable energy sources such as biomass is imperative. Biomass from animal waste such as horse manure has unutilized potential as it has yet to be implemented at a large scale as an energy source. Research has demonstrated the technical feasibility of using animal waste for energy conversion, though their supply chain cost poses a barrier, as does a gap in research regarding the specific design of efficient horse manure-to-energy supply chains. In response, we investigated the design of horse manure-to-energy supply chains through interviews and site visits at stables, as well as through interviews with transport companies. Our findings show that horse manure-to-energy supply chains have distinct attributes at all stages of the supply chain such as the geographical spread of stables that determines supply chain design and hampers efficiency. They share several such attributes with forest biomass-to-energy supply chains, from which important needs can be identified, including the industrial development of trucks dedicated to the purpose, mathematical modeling to handle the trade-off of cost of substance loss in storage and cost of transport, and business models that reconcile the conflicting goals of different actors along the supply chains.

  • 13.
    Söderholm, Patrik
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Sundqvist, Thomas
    Swedish Competition Authority.
    Empirical challenges in the use of learning curves for assessing the economic prospects of renewable energy technologies2007Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 32, nr 15, s. 2559-2578Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In bottom-up energy models endogenous technical change is introduced by implementing technology learning rates, which specify the quantitative relationship between the cumulative experiences of the technology on the one hand and cost reductions on the other. The main purpose of this paper is to critically analyze the choice of modeling and estimation strategies in learning curve analyses of power generation costs. We identify and discuss a number of theoretical and econometric issues involved in the estimation of learning curves. These include the presence of omitted variable bias and simultaneity, but also methodological problems related to the operationalization of theoretical concepts (i.e., learning-by-doing) and the associated use of data. We illustrate the importance of these issues by employing panel data for wind power installations in four western European countries, which are used to compare the results from different learning curve model specifications. The results illustrate that the estimates of learning rates may differ significantly across different model specifications and econometric approaches. The paper ends by outlining a number of recommendations for energy model analysts, who need to select appropriate energy technology learning rates from the empirical literature, or who choose to perform the empirical work themselves.

  • 14.
    Trivedi, Chirag
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Gandhi, B.K.
    Indian Institute of Technology, Roorkee.
    Cervantes, Michel
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Dahlhaug, O.G.
    Norwegian University of Science and Technology (NTNU), Trondheim.
    Experimental investigations of a model Francis turbine during shutdown at synchronous speed2015Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 83, s. 828-836Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hydraulic turbines are widely used to meet the real-time electricity demand at moderate to low cost. Intermittency in the power grid due to high penetration of wind and solar power has raised significant concerns for grid stability and reliability. The intermittency results in an increase of the start–stop cycles of hydraulic turbines. Each cycle induces fatigue to the turbine runner because it experiences unsteady pressure loading of high amplitude. The turbine runner accelerates freely due to an instantaneous transition into no load during shutdown. The amplitude of the unsteady pressure pulsation increases as the runner accelerates. To investigate the unsteady pressure pulsation, a shutdown slightly different from the normal shutdown was performed. Guide vanes were closed completely before the generator was disconnected from the load. The runner was spinning at constant angular speed through the generator. Amplitudes of the pressure pulsations were 20% and 35% lower in the vaneless space and the runner, respectively, compared to the normal shutdown of the turbine.

  • 15.
    Trubetskaya, Anna
    et al.
    School of Engineering and Ryan Institute, National University of Ireland Galway, Galway, Ireland.
    Souihi, Nabil
    Green Technologies and Environmental Economics Platform, Department of Chemistry, Umeå University, Umeå, Sweden.
    Umeki, Kentaro
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Categorization of tars from fast pyrolysis of pure lignocellulosic compounds at high temperature2019Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 141, s. 751-759Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study presents how the yields of different tar compounds from pure lignocellulosic compounds respond to the change in temperature and residence time. Experiments were carried out with a drop tube furnace in the temperature range from 800 to 1250 °C. The tar composition was characterized by gas chromatography with a flame ionization detector and mass spectrometry using a dual detector system. Longer residence time and higher heat treatment temperatures increased the soot formation and decreased the tar yields. Soot yields from lignin samples were greater than soot yields from holocellulose pyrolysis. The dominating products in tars from pyrolysis of all lignocellulosic compounds were benzene and toluene. Cellulose and hemicellulose pyrolysis produced greater amount of oxygenates in tars, whereas lignin tar was rich in phenols, polycyclic hydrocarbons and naphthalenes. Simultaneous reduction of tar and soot was achieved by impregnation of lignin from wheat straw with alkali metals. The OPLS-DA model can accurately explain the differences in tar composition based on the experimental mass spectrometry data.

  • 16.
    Wei, Juntao
    et al.
    Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, Shanghai.
    Gong, Yan
    Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, Shanghai.
    Guo, Qinghua
    Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, Shanghai.
    Chen, Xueli
    Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, Shanghai.
    Ding, Lu
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Yu, Guangsuo
    Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, Shanghai.
    A mechanism investigation of synergy behaviour variations during blended char co-gasification of biomass and different rank coals2018Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 131, s. 597-605Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Co-gasification reactivity of rice straw and bituminous coal/anthracite blended chars under CO2 atmosphere was evaluated using thermogravimetric analysis, and the influences of coal type and gasification temperature on synergy behaviour variations on co-gasification reactivity as carbon conversions increased were quantitatively studied. Furthermore, the chemical forms and concentrations of AAEM species at different co-gasification conversions were quantitatively analyzed for revealing co-gasification synergy mechanism. The results demonstrate that as conversions increased, synergy behaviour on co-gasification reactivity of rice straw-bituminous coal blends was shown as the weakened inhibition effect firstly and then the enhanced synergistic effect. Moreover, the inhibition effect on co-gasification reactivity of rice straw-bituminous coal blends was sustained up to higher conversion with the increment of gasification temperature. Differing from rice straw-bituminous coal blends, synergistic effect on co-gasification reactivity of rice straw-anthracite blends was obviously enhanced at early stage of co-gasification and started to slowly weaken after reaching the most significant synergistic effect at middle stage of co-gasification. Additionally, it was revealed that synergy behaviour variations on co-gasification reactivity of rice straw-bituminous coal blends were mainly attributed to the combination effects of active K and Ca transformation during co-gasification, while those of rice straw-anthracite blends indicated a good correlation with active K transformation during co-gasification.

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