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Performance Investigation of Biomass Gasification for Syngas and Hydrogen Production Using Aspen Plus

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Open Journal of Modelling and Simulation 2022年第2期10卷 71-87页

作者： Sahar Safarian runar Unnthorsson Christiaan Richter Faculty of Industrial Engineering Mechanical Engineering and Computer Science University of Iceland Reykjavik Iceland Division of Environmental Systems Analysis Department of Technology Management and Economics Chalmers University of Technology Gothenburg Sweden

This study presents a reliable model using Aspen Plus process simulator capable of performing a sensitivity analysis of the downdraft gasification linked to hydrogen production unit. Effects of key factors, including gasification temperature and steam to biomass ratio (SBR) on the syngas composition, calorific value of syngas and hydrogen production are discussed and then the optimal conditions for maximum hydrogen production are extracted. The model is validated by experimental and other modeling data and found to be in great agreement. The sensitivity analysis results obtained by only using air as gasification agent indicate that higher temperatures are favorable for a product gas with higher hydrogen content and calorific value. Moreover, steam consumption as gasifying agent leads to increasing the hydrogen content and heating value of the syngas compared to the use of air as gasification agent. Finally, the results show that the optimal conditions to have the highest value of hydrogen output from sawdust downdraft gasification are 800˚C as gasifier temperature and 0.6 for SBR.

关键词： Biomass Gasification Syngas Hydrogen Simulation Parametric Analysis

Effects of virus infection on expression of cell cycle regulatory proteins in the unicellular marine algae Emiliania huxleyi

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Acta Oceanologica Sinica 2011年第4期30卷 89-95页

作者： LIU Jingwen Gunnar Bratbak ZHENG Tianling runar Thyrhaug Bioengineering College of Jimei University Xiamen 361021 China Department of Microbiology University of Bergen Bergen N-5020 Norway Key Laboratory of MOE for Coast and Wetland Ecosystem School of Life Sciences XiamenUniversity Xiamen 361005 China State Key Laboratory of Marine Environmental Sciences of Xiamen University Xiamen 361005 China

The authors have investigated the biochemical events by which marine algal virus infection induces cell cycle arrest. The key G 2 /M-phase regulatory proteins are analyzed by immunobloting in unicel-lular Emiliania huxleyi,suggesting that virus induced cell cycle arrest is related with virus＇s effect on cyclins and cyclin dependent kinases. E. huxleyi virus（EhV） represses Cdc2/cyclinB complex activity by inhibiting the activity of Cdc2 kinase in a phosphorylation-related manner,blocking host cells G 2 /M checkpoint. Dephosphorylated /inactive Cdc25C combined with up-regulation of Wee1 expression at early infect period appears to be important mechanisms by which EhV represses Cdc2/cyclinB complex activity that is required for entry into M phase. This study has allowed us to confirm that algal virus infection leads to selective activation or inhibition of certain cell-cycle factors,which may play a significant role in establishing a more efficient environment for viral gene expression and DNA replication.

关键词： marine algal virus cell cycle regulators expression Emiliania huxleyi

Ischemia/reperfusion injury in porcine intestine-Viability assessment

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World Journal of Gastroenterology 2018年第18期24卷 2009-2023页

作者： runar J Strand-Amundsen Henrik M Reims Finn P Reinholt Tom E Ruud Runkuan Yang Jan O Hogetveit Tor I Tonnessen Department of Clinical and Biomedical Engineering Oslo University HospitalOslo 0424Norway Department of Physics University of OsloOslo 0316Norway Department of Pathology Oslo University HospitalOslo 0424Norway Institute for Surgical Research Oslo University HospitalOslo 0424Norway Department of Surgery Baerum HospitalVestre Viken Hospital TrustDrammen 3004Norway Department of Emergencies and Critical Care Oslo University HospitalOslo 0424Norway Institute of Clinical Medicine University of OsloOslo 0424Norway

AIM To investigate viability assessment of segmental small bowel ischemia/reperfusion in a porcine *** In 15 pigs, five or six 30-cm segments of jejunum were simultaneously made ischemic by clamping the mesenteric arteries and veins for 1 to 16 h. Reperfusion was initiated after different intervals of ischemia(1-8 h) and subsequently monitored for 5-15 h. The intestinal segments were regularly photographed and assessed visually and by palpation. Intraluminal lactate and glycerol concentrations were measured by microdialysis, and samples were collected for light microscopy and transmission electron microscopy. The histological changes were described and *** Using light microscopy, the jejunum was considered as viable until 6 h of ischemia, while with transmission electron microscopy the ischemic muscularis propria was considered viable until 5 h of ischemia. However, following ≥ 1 h of reperfusion, only segments that had been ischemic for ≤ 3 h appeared viable, suggesting a possible upper limit for viability in the porcine mesenteric occlusion model. Although intraluminal microdialysis allowed us to closely monitor the onset and duration of ischemia and the onset of reperfusion, we were unable to find sufficient level of association between tissue viability and metabolic markers to conclude that microdialysis is clinically relevant for viability assessment. Evaluation of color and motility appears to be poor indicators of intestinal *** Three hours of total ischemia of the small bowel followed by reperfusion appears to be the upper limit for viability in this porcine mesenteric ischemia model.

关键词： Viability histology reperfusion ischemia microdialysis jejunum porcine model

Techno-Economic Analysis of Power Production by Using Waste Biomass Gasification

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Journal of Power and Energy Engineering 2020年第6期8卷 1-8页

作者： Sahar Safarian runar Unnthorsson Christiaan Richter Faculty of Industrial Engineering Mechanical Engineering and Computer Science University of Iceland Reykjavik Iceland

Energy recovery from waste biomass can have significant impacts on the most pressing development challenges of rural poverty and environmental damages. In this paper, a techno-economic analysis is carried out for electricity generation by using timber and wood waste (T & WW) gasification in Iceland. Different expenses were considered, like capital, installation, engineering, operation and maintenance costs and the interest rate of the investment. Regarding to revenues, they come from of the electricity sale and the fee paid by the Icelandic municipalities for waste collection and disposal. The economic feasibility was conducted based on the economic indicators of net present value (NPV) and discounted payback period (DPP), bringing together three different subgroups based on gasifier capacities, subgroup a: 50 kW, subgroup b: 100 kW and subgroup c: 200 kW. The results show that total cost increases as the implemented power is increased. This indicator varies from 1228.6 k€ for subgroups a to 1334.7 k€ for subgroups b and 1479.5 k€ for subgroups c. It is worth mentioning that NPV is positive for three subgroups and it grows as gasifier scale is extended. NPV is about 122 k€ (111,020 $), 1824 k€ (1,659,840 $) and 4392 k€ (3,996,720 $) for subgroups a, b and c, respectively. Moreover, DPP has an inversely proportional to the installed capacity. It is around 5.5 years (subgroups a), 9.5 months (subgroups b) and 6 months (subgroups c). The obtained results confirm that using small scale waste biomass gasification integrated with power generation could be techno-economically feasible for remote area in Iceland.

关键词： Waste Biomass Gasification Techno-Economic Analysis Power Production Waste to Energy

Waste Biomass Gasification Simulation Using Aspen Plus: Performance Evaluation of Wood Chips, Sawdust and Mixed Paper Wastes

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Journal of Power and Energy Engineering 2019年第6期7卷 12-30页

作者： Sahar Safarian Christiaan Richter runar Unnthorsson Faculty of Industrial Engineering Mechanical Engineering and Computer Science University of Iceland Reykjavik Iceland

Biomass is one of the most widely available energy sources and gasification is a thermal conversion process where biomass is transformed into a fuel gas with a gasifying agent. In this paper by using ASPEN Plus, a new steady state simulation model for down draft waste biomass gasification was developed. The model that is stoichiometric equilibrium-based is proposed to be used for optimization of the gasifier performance. Prediction accuracy of the model is validated by comparing with available experimental and modeling results in other literature. Then the model is used for comparative analysis of the gasification performance of sawdust, wood chips and mixed paper wastes. In the model, the operating parameters of temperature and equivalence ratio (ER) have been varied over wide range and their effect on syngas composition, syngas yield, low heating value (LHV) of syngas and cold gas efficiency (CGE) has been investigated. Raise in temperature increases the production of CO and H2 which leads to higher syngas yield, LHV and CGE. However, increasing ER decreases the production of CO and H2 which results lessens in LHV and CGE but syngas yield continuously increases because more oxygen is available for biomass reactions at high ER. The optimal values of CO and H2 mole fraction and CGE of sawdust, wood chips and mixed paper wastes are located at 900°C, 1000°C and 1000°C, respectively and ER range is between 0.20 - 0.35 regardless of the kind of biomass which is used as the feedstock.

关键词： Waste Biomass Gasification Simulation Model Gasifier Performance Waste to Energy

升主动脉心外膜超声成像在冠状动脉旁路移植术中的价值

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中国医学影像技术 2005年第6期21卷 900-902页

作者：张宇虹 Kai Andersen runar Lundblad Halfdan Ihlen 大连医科大学附属二院超声科辽宁大连116027 挪威奥斯陆大学国家医院胸外科挪威奥斯陆0027 挪威奥斯陆大学国家医院胸外科挪威奥斯陆大学国家医院心内科超声实验室

目的　探讨心外膜超声技术在冠状动脉旁路移植术中检查升主动脉的临床意义。方法　应用心外膜超声探头在45例非体外循环旁路移植术中对升主动脉进行检查,判定是否形成粥样斑块及其程度,同时与术者触诊所得出的结果进行比较。术者根据斑... 详细信息

目的　探讨心外膜超声技术在冠状动脉旁路移植术中检查升主动脉的临床意义。方法　应用心外膜超声探头在45例非体外循环旁路移植术中对升主动脉进行检查,判定是否形成粥样斑块及其程度,同时与术者触诊所得出的结果进行比较。术者根据斑块部位及程度改变手术方法及方式。结果　45例中正常20例,动脉粥样斑块形成25例,其中轻度9 例、中度10例、重度6例。心外膜超声技术对升主动脉粥样斑块的检出率明显高于触诊检查。所有病例未发生围手术期中风。结论　应用心外膜超声技术可以较触诊更敏感地发现升主动脉粥样斑块形成,可以降低围手术期中风的发生率,具有重要的临床价值。

关键词：超声检查冠状动脉旁路移植术主动脉升

心外膜超声在非体外循环冠状动脉旁路移植术中对吻合口的评价

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中国医学影像技术 2004年第4期20卷 535-537页

作者：张宇虹 Kai Andersen runar Lundblad Halfdan Ihlen 大连医科大学附属二院超声科辽宁大连116027 挪威奥斯陆大学国家医院胸外科挪威奥斯陆大学国家医院心内科超声实验室

目的　探讨心外膜超声技术在非体外循环冠状动脉旁路移植术中对吻合口的评价及临床意义。方法　应用GE公司的新型心外膜超声探头对 3 2例非体外循环左乳内动脉左前降支动脉旁路移植术中吻合口进行检测。应用二维超声显像法 (2D)和彩色... 详细信息

目的　探讨心外膜超声技术在非体外循环冠状动脉旁路移植术中对吻合口的评价及临床意义。方法　应用GE公司的新型心外膜超声探头对 3 2例非体外循环左乳内动脉左前降支动脉旁路移植术中吻合口进行检测。应用二维超声显像法 (2D)和彩色多普勒显像法 (CDFI)获得吻合口的二维声像图并显示血流通畅情况 ,同时测量吻合口的相关径线。结果　所有病例均获得质量好的吻合口 2D声像图 ,CDFI显示吻合口均通畅。 2D结合CDFI对吻合口的评价结果与术中瞬时测血流量技术 (TTFM )的结果相一致 ,与术后立即进行的造影结果对比 ,符合率为 10 0 %。结论　应用新型探头的心外膜超声技术对左乳内动脉左前降支动脉旁路移植术中吻合口的评价具有重要的临床意义。

关键词：超声检查冠状动脉旁路移植术吻合口

国外木材关税变动对中国和世界木材产品贸易的影响——基于GFPM的分析（英文）

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林业经济评论 2013年 110-116页

作者：侯方淼 Tommy Lundgren runar Brannlund 北京林业大学经济管理学院瑞典农业大学林经系

为了保护环境并刺激国内木材加工,许多国家通过增加木材出口关税限制出口的木材,这将对中国和全球林产品生产和贸易产生影响。俄罗斯是国际木材贸易的主要国家。从2005年起,俄罗斯推出了木材出口税,并增加了很多次。本文模拟了俄罗斯工... 详细信息

为了保护环境并刺激国内木材加工,许多国家通过增加木材出口关税限制出口的木材,这将对中国和全球林产品生产和贸易产生影响。俄罗斯是国际木材贸易的主要国家。从2005年起,俄罗斯推出了木材出口税,并增加了很多次。本文模拟了俄罗斯工业原木出口关税的变化带来的各种影响,得出结论是原材料成本上升将进一步推高产品价格,对中国和全球林业会有长期的影响。如果考虑更多的国家采取类似的政策,将对中国和全球林业有更深远的影响。

关键词：关税木材产品贸易全球林产品模型

2002-2010年欧洲和北美28个国家15岁青少年在同时吸烟和大麻方面的趋势

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预防青少年犯罪研究 2017年第5期 114-118页

作者：安妮·哈勃利特周华珍(译) Pemille Bendtse Margreet E.de Looze Peter Donnelly runar Vilhjalmsson Tibor Baska Katrin Aasvee Iva P.Franelic SaoirseNic Gabhainn Tom F.M.ter Bogt AnastasiosFotiou 根特大学公共卫生系中国青年政治学院青少年健康研究中心南丹麦大学国家公共卫生研究所乌特勒支大学社会科学跨学科研究所圣安德鲁斯大学医学院冰岛大学护理学院夸美纽斯大学Jessenius医学院国立健康发展研究所慢性病系克罗地亚国立公共卫生研究所爱尔兰国立大学健康促进研究中心大学精神健康研究所流行病学部

吸食大麻和吸烟经常共现,同时吸烟和大麻的青少年更容易出现呼吸困难和社会心理问题。本文运用"世界卫生组织-学龄儿童健康行为"模型收集了欧洲和北美33个参与国家在2002-2010年间有关15岁青少年在吸烟和吸食大麻方面的时间变化趋势。

关键词：青少年吸烟和吸食大麻共现时间变化趋势