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In this work, integration of a synthetic natural gas (SNG) production process with an existing biomass CHP steam power cycle is investigated. The paper assesses two different biomass feedstock drying technologies—steam drying and low‐temperature air drying—for the SNG process. Using pinch technology, different levels of thermal integration between the steam power cycle and the SNG process are evaluated. The base case cold gas efficiency for the SNG process is 69.4% based on the lower heating value of wet fuel. The isolated SNG‐related electricity production is increased by a factor of 2.5 for the steam dryer alternative, and tenfold for the low‐temperature air dryer when increasing the thermal integration. The cold gas efficiency is not affected by the changes. Based on an analysis of changes to turbine steam flow, the integration of SNG production with an existing steam power cycle is deemed technically feasible. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Bothwell Batidzirai Geert S. Schotman Mijndert W. van der Spek Martin Junginger Andr P. C. Faaij 《Biofuels, Bioproducts and Biorefining》2019,13(2):325-357
Synthetic natural gas (SNG) derived from biomass gasification is a potential transport fuel and natural gas substitute. Using the Netherlands as a case study, this paper evaluates the most economic and environmentally optimal supply chain for the production of biomass based SNG (so‐called bio‐SNG) for different biomass production regions and location of final conversion facilities, with final delivery of compressed natural gas at refueling stations servicing the transport sector. At a scale of 100 MWth, in, delivered bioSNG costs range from 18.6 to 25.9$/GJdelivered CNG while energy efficiency ranges from 46.8–61.9%. If production capacities are scaled up to 1000 MWth, in, SNG costs decrease by about 30% to 12.6–17.4$ GJdelivered CNG−1. BioSNG production in Ukraine and transportation of the gas by pipeline to the Netherlands results in the lowest delivered cost in all cases and the highest energy efficiency pathway (61.9%). This is mainly due to low pipeline transport costs and energy losses compared to long‐distance Liquefied Natural Gas (LNG) transport. However, synthetic natural gas production from torrefied pellets (TOPs) results in the lowest GHG emissions (17 kg CO2e GJCNG−1) while the Ukraine routes results in 25 kg CO2e GJCNG−1. Production costs at 100 MWth are higher than the current natural gas price range, but lower than the oil prices and biodiesel prices. BioSNG costs could converge with natural gas market prices in the coming decades, estimated to be 18.2$ GJ−1. At 1000 MWth, bioSNG becomes competitive with natural gas (especially if attractive CO2 prices are considered) and very competitive with oil and biodiesel. It is clear that scaling of SNG production to the GWth scale is key to cost reduction and could result in competitive SNG costs. For regions like Brazil, it is more cost‐effective to densify biomass into pellets or TOPS and undertake final conversion near the import harbor. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
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以生物质气化气中的CO2为研究对象,研究压力、气液比、四丁基溴化铵(TBAB)浓度和洗焦废水对CO2分离效率的影响。结果表明:CO2的分离效率(分离因子)随进气压力的增大先增大后减小;随气液比的增加先减小后增大;达到水合物形成的平衡压力后,随TBAB浓度的增大而减小。较低浓度的洗焦废水由于可增加气体的溶解速率并减少水合物的诱导时间而增加水合物的形成速率。在2.1 MPa、气液比14.63、TBAB物质的量浓度为0.29%时,CO2分离效率最高,分离后气相CO2气体含量由17.85%下降到8.71%,目标气体H2、CO损失率约为5%,水合物相中CO2含量达81.63%。 相似文献
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The gasification of biomass can be coupled to a downstream methanation process that produces synthetic natural gas (SNG). This enables the distribution of bioenergy in the existing natural gas grid. A process model is developed for the small‐scale production of SNG with the use of the software package Aspen Plus (Aspen Technology, Inc., Burlington, MA, USA). The gasification is based on an indirect gasifier with a thermal input of 500 kW. The gasification system consists of a fluidized bed reformer and a fluidized bed combustor that are interconnected via heat pipes. The subsequent methanation is modeled by a fluidized bed reactor. Different stages of process integration between the endothermic gasification and exothermic combustion and methanation are considered. With increasing process integration, the conversion efficiency from biomass to SNG increases. A conversion efficiency from biomass to SNG of 73.9% on a lower heating value basis is feasible with the best integrated system. The SNG produced in the simulation meets the quality requirements for injection into the natural gas grid. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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D. Vamvuka 《国际能源研究杂志》2011,35(10):835-862
As the global demand for energy rapidly increases and fossil fuels will be soon exhausted, bio‐energy has become one of the key options for shorter and medium term substitution for fossil fuels and the mitigation of greenhouse gas emissions. Biomass currently supplies 14% of the world's energy needs. Biomass pyrolysis has a long history and substantial future potential—driven by increased interest in renewable energy. This article presents the state‐of‐the‐art of biomass pyrolysis systems, which have been—or are expected to be—commercialized. Performance levels, technological status, market penetration of new technologies and the costs of modern forms of biomass energy are discussed. Advanced methods have been developed in the last two decades for the direct thermal conversion of biomass to liquid fuels, charcoals and various chemicals in higher yields than those obtained by traditional pyrolysis processes. The most important reactor configurations are fluidized beds, rotating cones, vacuum and ablative pyrolysis reactors. Fluidized beds and rotating cones are easier for scaling and possibly more cost effective. Slow pyrolysis is being used for the production of charcoal, which can also be gasified to obtain hydrogen‐rich gas. The short residence time pyrolysis of biomass (flash pyrolysis), at moderate temperatures, is being used to obtain a high yield of liquid products (up to 70% wt), particularly interesting as energetic vectors. Bio‐oil can substitute for fuel oil—or diesel fuel—in many static applications including boilers, furnaces, engines and turbines for electricity generation. While commercial biocrudes can easily substitute for heavy fuel oils, it is necessary to improve the quality in order to consider biocrudes as a replacement for light fuel oils. For transportation fuels, high severity chemical/catalytic processes are needed. An attractive future transportation fuel can be hydrogen, produced by steam reforming of the whole oil, or its carbohydrate‐derived fraction. Pyrolysis gas—containing significant amount of carbon dioxide, along with methane—might be used as a fuel for industrial combustion. Presently, heat applications are most economically competitive, followed by combined heat and power applications; electric applications are generally not competitive. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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This paper presents thermodynamic evaluations of the agriculture residual-to-SNG process by thermochemical conversion, which mainly consists of the interconnected fluidized beds, hot gas cleaning, fluidized bed methanation reactor and Selexol absorption unit. The process was modeled using Aspen Plus software. The process performances, i.e., CH 4 content in SNG, higher heating value and yield of SNG, exergy efficiencies with and without heat recovery, unit power consumption, were evaluated firstly. The results indicate that when the other parameters remain unchanged, the steam-to-biomass ratio at carbon boundary point is the optimal value for the process. Improving the preheating temperatures of air and gasifying agent is beneficial for the SNG yield and exergy efficiencies. Due to the effects of CO 2 removal efficiency, there are two optimization objectives for the SNG production process: (I) to maximize CH 4 content in SNG, or (II) to maximize SNG yield. Further, the comparison among different feedstocks indicates that the decreasing order of SNG yield is: corn stalk > wheat straw > rice straw. The evaluation on the potential of agriculture-based SNG shows that the potential annual production of agriculture residual-based SNG could be between 555×10 8～611×10 8 m 3 with utilization of 100% of the available unexplored resources. The agriculture residual-based SNG could play a significant role on solving the big shortfall of China’s natural gas supply in future. 相似文献
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Jussi Heinim Heikki Malinen Tapio Ranta Andr Faaij 《Biofuels, Bioproducts and Biorefining》2011,5(3):238-249
Introduction of second‐generation biofuels is an essential factor for meeting the EU's 2020 targets for renewable energy in the transport sector and enabling the more ambitious targets for 2030. Finland's forest industry is strongly involved in the development and commercializing of second‐generation biofuel production technologies. The goal of this paper is to provide a quantified insight into Finnish prospects for reaching the 2020 national renewable energy targets and concurrently becoming a large‐scale producer of forest‐biomass‐based second‐generation biofuels feeding the increasing demand in European markets. The focus of the paper is on assessing the potential for utilizing forest biomass for liquid biofuels up to 2020. In addition, technological issues related to the production of second‐generation biofuels were reviewed. Finland has good opportunities to realize a scenario to meet 2020 renewable energy targets and for large‐scale production of wood‐based biofuels. In 2020, biofuel production from domestic forest biomass in Finland may reach nearly a million ton (40 PJ). With the existing biofuel production capacity (20 PJ/yr) and the national biofuel consumption target (25 PJ) taken into account, the potential net export of biofuels from Finland in 2020 would be 35 PJ, corresponding to 2–3% of European demand. Commercialization of second‐generation biofuel production technologies, high utilization of the sustainable harvesting potential of Finnish forest biomass, and allocation of a significant proportion of the pulpwood harvesting potential for energy purposes are prerequisites for this scenario. Large‐scale import of raw biomass would enable remarkably greater biofuel production than is described in this paper. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
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根据最小吉布斯自由能理论,采用ASPEN模拟软件,计算分析了生物质一步制氢过程中,温度、压力、汽碳比以及钙碳比对气化过程的影响,并对该制氢过程进行了实验研究。研究结果表明,随气化温度的升高,气体产物中氢的含量增加;生物质一步制氢比较适宜的气化压力约为2.0MPa;在最佳的压力范围内,钙碳比合适的比例为2.0;高的汽碳比可以抑制甲烷的生成,但其值大于5后其影响明显减弱。对不同种类的生物质的实验研究表明:种类广泛的生物质,均能在该文确定的条件下实现一步制氢和二氧化碳等的同步脱除。 相似文献
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Jean‐Paul Lange 《Biofuels, Bioproducts and Biorefining》2007,1(1):39-48
Governments across the world are stimulating the valorization of local biomass to secure the energy supply, reduce the emissions of fossil CO2 and support the rural economy. A first generation of fuels and chemicals is being produced from high‐value sugars and oils. Meanwhile, a second generation, based on cheaper and more abundant lignocellulosic feedstock, is being developed. This review addresses the variety of chemistries and technologies that are being explored to valorize lignocellulosic biomass. It shows the need to ‘deoxygenate’ the biomass and reviews the main chemical routes for it, i.e. a) the pyrolysis to char, bio‐crude or gas; b) the gasification to syngas and its subsequent conversion, e.g. to alkanes or methanol; c) the hydrolysis to sugar and their subsequent upgrading to oxygenated intermediates via chemical or fermentation routes. The economics of biomass conversion also needs to be considered: the current production cost of biofuels are typically $60–120/barrel of oil equivalent. Influential factors include the cost of the biomass at the plant gate, the conversion efficiency, the scale of the process and the value of the product (e.g. fuel, electricity or chemicals). © 2007 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
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This paper explored the feasibility and benefit of CO2 utilization as gasifying agent in the autothermal gasification process. The effects of CO2 injection on reaction temperature and producer gas composition were examined in a pilot scale downdraft gasifier by varying the CO2/C ratio from 0.6 to 1.6. O2 was injected at an equivalence ratio of approximately 0.33–0.38 for supplying heat through partial combustion. The results were also compared with those of air gasification. In general, the increase in CO2 injection resulted in the shift of combustion zone to the downstream of the gasifier. However, compared with that of air gasification, the long and distributed high temperature zones were obtained in CO2-O2 gasification with a CO2/C ratio of 0.6–1.2. The progress of the expected CO2 to CO conversion can be implied from the relatively insignificant decrease in CO fraction as the CO2/C ratio increased. The producer gas heating value of CO2-O2 gasification was consistently higher than that of air gasification. These results show the potential of CO2-O2 gasification for producing high quality producer gas in an efficient manner, and the necessity for more work to deeply imply the observation. 相似文献
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生物质气化制氢有重要的工业应用价值,本文采用ASPEN PLUS软件数值模拟了稻壳在流化床中的气化过程。本次模拟运用吉布斯自由能最小化原理,选择RGibbs和RYield模块,采用CO2作为气化剂,计算获得了气化温度、CO2质量流量、CO2和稻壳质量比和碳转化率对产氢率的影响规律。结果表明：在CO2质量流量为200kg/h时,H2的生成率高达43%。随着CO2/B增加,CO和CO2体积分数逐渐升高,CH4体积分数下降,H2体积分数在不同的气化温度下趋于平稳（600~700℃）或下降（800~1000℃）。随着气化温度升高,碳转化率增加;随着CO2和稻壳质量比的升高,碳转化率下降。 相似文献
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利用Aspen Plus 软件建立干桦木屑在下吸式固定床气化炉中的气化模型,模拟值与文献实验值吻合良好。利用Aspen Plus的灵敏度分析模块模拟分别以水蒸气（H2O）和二氧化碳（CO2）为气化剂时气化剂/生物质碳比（GC值）对气化结果的影响,并结合H2O、CO2各自的特点研究其复合气化。结果表明,H2O气化时可获得富氢煤气,但其净CO2排放量较高;CO2气化时碳转化率及冷煤气效率较低,但净CO2排放量较低;H2O、CO2复合气化使碳转化率及冷煤气效率略有降低,但可有效减少气化系统中的净CO2排放量。 相似文献
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Ryan P. Lively Pradeep Sharma Benjamin A. McCool Jacques Beaudry‐Losique Dexin Luo Valerie M. Thomas Matthew Realff Ronald R. Chance 《Biofuels, Bioproducts and Biorefining》2015,9(1):72-81
Biofuels have great potential as low‐carbon transportation fuel alternatives and can be essentially drop‐in fuels for existing fossil‐fuel‐based transportation infrastructures. Thus, the incentives for biofuel development are large but there are a number of issues: competition with food, land use, fresh water use, economics in comparison to fossil fuels, and achievable reduction in carbon footprint in comparison to other transportation fuel options. This paper focuses on utilization of anthropogenic CO2 from power plants in advanced biofuel production systems and the integration of those systems with various power plant designs. In doing so, the boundary of the life cycle analysis is expanded to include the power plant CO2 source, considering specifically natural gas, pulverized coal, supercritical coal, and IGCC (integrated gasification combined cycle) options. The carbon footprints for the integrated systems are compared to CCS (carbon capture and sequestration) as well as the current status quo of CO2 release to the atmosphere. The integrated biorefinery‐power plant options considered here are shown to be greatly advantaged compared to the status quo (no CO2 capture) carbon footprint, and also advantaged with respect to CCS as long as the biorefinery alone operates with a carbon footprint that is 75% or more lower than that of gasoline. In addition, the projected carbon footprint values, and estimated production costs, for algal‐based ethanol are favorable compared to other transportation fuel options including corn‐based ethanol and electricity. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
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A promising renewable energy technology is electricity generated with biomass‐derived synthetic gas (syngas). The economic feasibility of using biomass gasification for generating electrical power is very much dependent on the cost of the power plant and the cost of its operation. A cost model was developed to analyze the Unit Cost (unit‐cost) of electricity generation from micro‐scale power facilities that used biomass gasification as its energy input. The costs considered in the model were capital cost and operating costs. The results from the modeling indicated that operating cost was a major part of the total annual production cost of electricity generation, and that labor was the largest part of the total annual production cost of operation, and it was during the time when the power facilities operated at lower generation capacity levels. One effective way of reducing the unit‐cost was to operate the facility at high capacity level. The study found that when the capacity level increased the total of annual cost was also increased, but the electricity unit‐cost decreased markedly. For a given level of generating capacity, the electricity unit‐cost of the facility operating at a two or three shifts operating mode was significantly lower than that of one shift operating mode. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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In this paper we show the effects of expanding the system when evaluating well‐to‐wheel (WTW) CO2 emissions for biomass‐based transportation, to include the systems surrounding the biomass conversion system. Four different cases are considered: DME via black liquor gasification (BLG), methanol via gasification of solid biomass, lignocellulosic ethanol and electricity from a biomass integrated gasification combined cycle (BIGCC) used in a battery‐powered electric vehicle (BPEV). All four cases are considered with as well as without carbon capture and storage (CCS). System expansion is used consistently for all flows. The results are compared with results from a conventional WTW study that only uses system expansion for certain co‐product flows. It is shown that when expanding the system, biomass‐based transportation does not necessarily contribute to decreased CO2 emissions and the results from this study in general indicate considerably lower CO2 mitigation potential than do the results from the conventional study used for comparison. It is shown that of particular importance are assumptions regarding future biomass use, as by expanding the system, future competition for biomass feedstock can be taken into account by assuming an alternative biomass usage. Assumptions regarding other surrounding systems, such as the transportation and the electricity systems are also shown to be of significance. Of the four studied cases without CCS, BIGCC with the electricity used in a BPEV is the only case that consistently shows a potential for CO2 reduction when alternative use of biomass is considered. Inclusion of CCS is not a guarantee for achieving CO2 reduction, and in general the system effects are equivalent or larger than the effects of CCS. DME from BLG generally shows the highest CO2 emission reduction potential for the biofuel cases. However, neither of these options for biomass‐based transportation can alone meet the needs of the transport sector. Therefore, a broader palette of solutions, including different production routes, different fuels and possibly also CCS, will be needed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Blanca Antizar‐Ladislao Juan L. Turrion‐Gomez 《Biofuels, Bioproducts and Biorefining》2008,2(5):455-469
First‐generation biofuels, mainly from corn and other food‐based crops are being used as a direct substitute for fossil fuels in transport. However, they are available in limited volumes that do not make them serious replacements for petroleum. Second‐generation biofuels from forest and crop residues, energy crops and municipal and construction waste, will arguably reduce net carbon emission, increase energy effi ciency and reduce energy dependency, potentially overcoming the limitations of fi rst‐generation biofuels. Nevertheless, implementation of second‐generation biofuels technology will require a sustainable management of energy, or development of local bioenergy systems. This study aims at identifying second‐generation biofuel feedstock. It also provides information on the available technologies to produce second‐generation biofuels. Finally it discusses the development of local bioenergy systems vs sustainable use of second‐generation biofuels. Locally produced second‐generation biofuels will exploit local biomass to optimize their production and consumption. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献