In the current study, processes to produce either ethanol or a representative fatty acid ethyl ester (FAEE) via the fermentation of sugars liberated from lignocellulosic materials pretreated in acid or alkaline environments are analyzed in terms of economic and environmental metrics. Simplified process models are introduced and employed to estimate process performance, and Monte Carlo analyses were carried out to identify key sources of uncertainty and variability. We find that the near-term performance of processes to produce FAEE is significantly worse than that of ethanol production processes for all metrics considered, primarily due to poor fermentation yields and higher electricity demands for aerobic fermentation. In the longer term, the reduced cost and energy requirements of FAEE separation processes will be at least partially offset by inherent limitations in the relevant metabolic pathways that constrain the maximum yield potential of FAEE from biomass-derived sugars.

关键词：生物化学;乙醇;乙酯;柳枝稷;碱性;生物量;脂肪酸;发酵;木质材料;指标;蒙特卡罗法;生产;分离流程;糖

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This report describes in detail one potential conversion process to hydrocarbon products by way of biological conversion of lignocellulosic-derived sugars. The pathway model leverages expertise established over time in core conversion and process integration research at NREL, while adding in new technology areas primarily for hydrocarbon production and associated processing logistics. The overarching process design converts biomass to a hydrocarbon intermediate, represented here as a free fatty acid, using dilute-acid pretreatment, enzymatic saccharification, and bioconversion. Ancillary areas--feed handling, hydrolysate conditioning, product recovery and upgrading (hydrotreating) to a final blendstock material, wastewater treatment, lignin combustion, and utilities--are also included in the design. Detailed material and energy balances and capital and operating costs for this baseline process are also documented.

关键词：生物质;木质纤维素;糖类;碳氢化合物生物转化;设计;经济分析;酶活性;液体燃料;运营成本;生产;技术评估

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The overall objective of this study was to select chemical processing equipment, install and operate that equipment to directly convert algae to biodiesel via a reaction patented by Old Dominion University (Pat. No. US 8,080,679B2). This reaction is a high temperature (250-330 degrees C) methylation reaction utilizing tetramethylammonium hydroxide (TMAH) to produce biodiesel. As originally envisioned, algal biomass could be treated with TMAH in methanol without the need to separately extract triacylglycerides (TAG). The reactor temperature allows volatilization and condensation of the methyl esters whereas the spent algae solids can be utilized as a high-value fertilizer because they are minimally charred. During the course of this work and immediately prior to commencing, we discovered that glycerol, a major by-product of the conventional transesterification reaction for biofuels, is not formed but rather three methoxylated glycerol derivatives are produced. These derivatives are high-value specialty green chemicals that strongly upgrade the economics of the process, rendering this approach as one that now values the biofuel only as a by-product, the main value products being the methoxylated glycerols. A horizontal agitated thin-film evaporator (one square foot heat transfer area) proved effective as the primary reactor facilitating the reaction and vaporization of the products, and subsequent discharge of the spent algae solids that are suitable for supplementing petrochemical-based fertilizers for agriculture. Because of the size chosen for the reactor, we encountered problems with delivery of the algal feed to the reaction zone, but envision that this problem could easily disappear upon scale-up or can be replaced economically by incorporating an extraction process. The objective for production of biodiesel from algae in quantities that could be tested could not be met, but we implemented use of soybean oil as a surrogate TAG feed to overcome this limitation.

关键词：藻类;替代燃料;农药;生物量;化学加工;柴油燃料;酯类;提取;化肥;甘油;实施;石化;弗吉尼亚州;生物柴油

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A greenhouse heating mode was proposed in this paper in order to reduce energy consumption and increase the efficiency of heating system for greenhouse.Considering experimental greenhouse practical operating conditions and various environmental factors, a warm air heating system, with heat source of biomass boilers, end heat abstractor of fan coils, was designed and some winter heating experiments was conducted.With the CFD method, the modelling of thermal environment inside the greenhouse in winter night was realized, temperature variation and distribution was simulated by STAR-CCM+.The simulation results were compared with experimental temperatures at the key positions in the greenhouse, and indicated that temperature errors of the monitoring points were less than 2K, relative error less than 8％, calculated root-mean-square error was 0.47K.Thus the validity of proposed model was certified.

关键词：载荷及温室;温度分布;实验研究;数值模拟

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报告从行业环境、太阳能、风能、生物质能、新能源汽车等几个方面进行了分析及评论。

关键词：太阳能；风能；生物质能；新能源汽车

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This report describes a proposed thermochemical process for converting biomass into liquid transportation fuels via fast pyrolysis followed by hydroprocessing of the condensed pyrolysis oil. As such, the analysis does not reflect the current state of commercially-available technology but includes advancements that are likely, and targeted to be achieved by 2017. The purpose of this study is to quantify the economic impact of individual conversion targets to allow a focused effort towards achieving cost reductions.

关键词：生物质转换;木质纤维素,碳氢化合物,生物燃料;热解;降低成本;经济影响;加氢处理;食用油;热化学过程;运输燃料

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A comprehensive process model is developed for high temperature air-steam biomass gasification in a downdraft gasifier using the ASPEN PLUS simulator.The simulation results are compared with the experimental data obtained through pilot scale downdraft gasifier.In this study,the model is used to investigate the effects of gasifying agent preheating,equivalence ratio (ER),and steam/biomass (S/B) on producer gas composition,high heating value (HHV),and cold gas efficiency (CGE).Results indicate that H2 and CO contents have increased when gasifying agent preheating is used,while gasifying agent preheating has no effect with H2 and CO at high ER.At high level of S/B,the concentrations of H2 and CO are related with water-gas shift reaction in significant.HHV and CGE depend on the concentrations of H2 and CO in producer gas,which can increase by preheated gasifying agent.However,gasifying agent preheating should apply with waste heat from the process because there is no additional cost of energy price.

关键词：气流气化炉；高温空气蒸汽；生物质气化

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在当前资源环境形势日益严峻的背景下，加强我国煤炭需求峰值预测，提前做好产能规划与部署，对于科学推动煤炭消费总量控制，实现煤炭产业健康、稳定和可持续发展意义重大。本研究基于计量经济学理论，针对改革开放后（1978－2013年）的样本数据，构建了基于煤炭需求的多因素协整模型（CM）、误差修正模型（ECM）和向量误差修正模型（VECM），比较发现，ECM的模型性能和拟合效果更佳；随后，基于ECM对未来我国煤炭的需求峰值进行了预测和分析，结果表明，我国煤炭需求峰值预计出现在2020年，峰值水平为45亿吨；2020年前，煤炭需求量年均增幅3.9%，2020年后开始出现下降，年均降幅0.76%，到2030年降至42亿吨。面对即将到来的煤炭峰值，政府管理部门应及早谋划、加强应对，切实推动煤炭产业转型升级和可持续发展。

关键词：煤炭需求；峰值；应对

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2004年西气东输管道的正式商业运作，标志着我国天然气进入快速发展期。近10年来，我国已形成了“西气东输、海气登陆、就近供应"的供气格局，天然气行业发展具备了一定的基础。天然气绝对消费量已从2004年的341亿立方米增长到2013年的1640亿立方米，我国已超过伊朗成为世界第三大天然气消费国。然而，随着经济的快速发展，我国环境压力持续增大。为此，国务院推出了大气污染防治行动计划(国发[2013]37号)等环境政策。天然气作为实现节能减排和治理大气污染最现实的清洁能源，进一步加大发展力度势在必行。笔者拟在此背景下，综合评价我国天然气资源、市场、基础设施现状及水平，探讨未来天然气行业的定位以及实现“大力发展"所需要的基础条件；基于“大力发展"的视角，对我国未来天然气供应能否满足市场需求目标，基础设施建设能力能否与市场规模相匹配，下游天然气利用能否适应上游发展速度、实现均衡发展，不同用户在未来市场条件下的承受能力等问题和风险进行评估，并根据评估结果，提出具有可实施性的保障措施建议，为促进我国天然气快速发展提供有针对性的参考意见。

关键词：天然气；风险因素；对策建议

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关键词：致密气；年产量

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