制取燃料乙醇的甜高粱

制取燃料乙醇(酒精)作为内燃机的代用燃料,近年来在国外已日渐引起人们的注意。在巴西,乙醇已作为内燃机的燃料大量使用,在国民经济中占有重要地位。在美国,乙醇作为一种添加剂以替代铅与汽油     

略谈甜高粱茎秆制取燃料乙醇

由于化石能源资源有限，且环境问题突出．国际上对生物质制取液体燃料早巳提到议事日程。近年来，我国进口石油日益增多，能源压力很大。国家科技部和国家发改委等部门正在编制国家中长期能源发展规划，已将可再生能源中的生物质制取液体燃料列为重点项目之一。利用生物质制取液体燃料，推广应用车用乙醇汽油，既解决急需．也利于能源结构优化，特别与国家能源安全有关。     

甜高粱制燃料乙醇项目经济效益调查分析——以黑龙江桦川县甜高粱制乙醇项目为例

以甜高粱茎秆为原料,制取燃料乙醇作为替代能源,对于解决制约我国经济发展的能源问题大有裨益,成为目前国家大力推广的新兴项目。文章实地调查了国家"863"计划的试点项目-黑龙江桦川县甜高粱制乙醇项目,对该项目中农户和企业的经济效益进行了详细的分析。其结果显示,农户在旱地种植甜高粱的收益比种植大豆和玉米的收益高很多,达到8 060元/hm2。通过分析,企业净收益可以达到每年1 510万元左右,投资回报率为15.11%,投资回收期为7 a。桦川县甜高粱制乙醇项目实现了农户、企业"双赢"的局面,为国家发展类似项目的经济可行性提供了可靠依据。     

甜高粱秸秆燃料乙醇产业化问题与对策的探讨

甜高粱具有极高的光合速率,有"高能植物"之称,其单位种植面积的乙醇产量较高.甜高粱特别适合在我国栽培,甜高粱燃料乙醇极具开发价值,它对能源安全和环境保护具有举足轻重的作用.文章简单介绍了新疆甜高粱用于生产低成本燃料乙醇的优势、试验情况以及产业化过程中面临的问题,并提出了解决这些问题应采取的对策.     

甜高梁制燃料乙醇项目经济效益调查分析——以黑龙江桦川县甜高粱制乙醇项目为例

以甜高粱茎秆为原料，制取燃料乙醇作为替代能源，对于解决制约我国经济发展的能源问题大有裨益，成为目前国家大力推广的新兴项目。文章实地调查了国家“863”计划的试点项目-黑龙江桦川县甜高粱制乙醇项目，对该项目中农户和企业的经济效益进行了详细的分析。其结果显示，农户在旱地种植甜高粱的收益比种植大豆和玉米的收益高很多，达到8060元／hm^2。通过分析，企业净收益可以达到每年1510万元左右，投资回报率为15．11％，投资回收期为7a。桦川县甜高粱制乙醇项目实现了农户、企业“双赢”的局面．为国家发展类似项目的经济可行性提供了可靠依据。     

甜高梁茎秆固态发酵制取燃料乙醇过程分析与中试研究

研究了甜高粱秆固态发酵生产燃料乙醇过程工艺参数的变化规律及相关性,并以此为基础进行了5m~3转鼓式固态发酵反应器中试试验.结果表明:糖份的快速消耗伴随着乙醇的大量产生,酵母分泌相关酶类使非还原糖向还原糖转化;发酵过程pH下降,对乙醇产生无明显抑制;搅拌可以改善传质、传热,有利于菌体的生长和发酵的进行.中试结果表明40～44h内可完成发酵.直接固态发酵与蒸馏后获得30%～40%的粗醇溶液,平均13.5～15.5kg甜高粱秆产1kg(99.5%)无水乙醇,糟渣粗蛋白含量6.94%(干基),可替代"黄储"饲料.糖利用率最高97.50%,乙醇实际收率最高94.48%.     

甜高粱茎杆制燃料乙醇工程路线探讨

探讨了用甜高粱茎杆工业化生产燃料乙醇的工程路线,分析了工业生产三个明确目标和要求,五个具体矛盾和困难。根据实践采取相应措施,提出了分布式加工体系,循环型经济模式和生物法生产工艺三位一体的完整工程路线。     

山东滨州甜高粱种植基地及燃料乙醇中试装置考察报告

国务院扶贫办中国地区开发促进会常务副会长、甜高粱产业发展中心主任、中国能源理事会理事张管生教授说：“当前，可再生能源热吸引了很多人，生物液体能源开发成为热中之热，尤其是甜高粱秸杆制乙醇，高层领导和普通百姓都十分关心。但客观情况是理论探讨多，实际行动少；短期行为多，长期坚持少；‘钓鱼’项目多，‘真投’项目少；照搬传统多，自主创新少；小型试验多，中试工程少。”     

甜高粱制燃料乙醇的原料和工艺

甜高粱生物产量高,适应能力强,被誉为最有希望的能源作物。世界许多国家竞相开发甜高粱制取燃料乙醇的技术。针对甜高粱规模化生产燃料乙醇的重要影响因素,论述了良种选育、栽培技术、储藏技术、生产工艺和综合利用等方面的研究现状,从原料工程和生产工艺的角度阐述了各环节的重要作用．从综合利用的角度评估了甜高粱的制燃料乙醇的技术经济性。     

油污地甜高粱茎秆汁液制取酒精的试验研究

采用正交试验的方法,以辽宁沈抚污灌区栽种的甜高粱茎秆为试材,研究了氮、钾、镁营养盐填加量对酒精产率的影响,确定了甜高梁发酵酒精的适宜工艺。结果表明,在油污地栽种的甜高粱可用来发酵生产酒精;在发酵液中添加0．5％的磷酸二氧钾,0．05％的硫酸铵,0．05％的硫酸镁,5-6h后可得到较高的酒精产率（可达理论产率的93％）。     

Antagonistic bioenergies: Technological divergence of the ethanol industry in Brazil

We present evidence for the coexistence of two antagonistic sugarcane ethanol production technologies in Brazil, with the Southeast region of the country having relatively mechanized production processes, and the Northeast area using labor-intensive ones. We highlight the main differences between the hand-production and fully automated mechanical manufacturing in the Brazilian ethanol industry and examine the historical, political, and economic factors that induced this regional technology gap that is currently observed. We then construct an environmental model based on a 375-industry interregional input–output system for the Brazilian regions, in order to determine the extent to which the primitive ethanol production of Northern Brazil differs from the automated manufacture technologies of the South in terms of greenhouse gas emissions. We show that ethanol produced with modern technologies generates lower carbon dioxide (CO₂) emissions than ethanol produced with traditional production processes. We also demonstrate that ethanol, regardless of the technology with which it was produced, is more carbon-efficient than petrochemical products.     

中国甘蔗燃料乙醇生产的技术、经济和环境可行性分析

我国甘蔗燃料乙醇产业的发展是以2001年国家基于石油替代战略而启动“变性燃料乙醇”和“车用燃料乙醇”计划为背景发展起来的。目前燃料乙醇发展的突出障碍是生产成本较高,因此,需要国家的大量补贴。文中借鉴巴西利用甘蔗发展低成本燃料乙醇的经验,对中国甘蔗燃料乙醇生产的技术成熟度、市场竞争力和环境影响进行了分析,并得出：中国用甘蔗生产燃料乙醇在工艺和设备上不存在根本性、长期性的障碍;在目前的燃料乙醇和食糖价格下,甘蔗燃料乙醇的生产具有相对优势;甘蔗燃料乙醇生产中对环境的负面影响在现有的环保技术条件下可以得到克服,并且还将促进温室气体减排。     

Design and analysis of fuel ethanol production from raw glycerol

Three configurations for fuel ethanol production from raw glycerol using Escherichia coli were simulated and economically assessed using Aspen Plus and Aspen Icarus, respectively. These assessments considered raw glycerol (60 wt%) purification to both crude glycerol (88 wt%) and pure glycerol (98 wt%). The highest purification cost (PC) was obtained using pure glycerol due to its higher energy consumption in the distillation stage. In addition, the remaining methanol in the raw glycerol stream was recovered and recycled, decreasing the purification costs. The E. coli strain is able to convert crude glycerol (at 10 g/L or 20 g/L), or pure glycerol (at 10 g/L) to ethanol. Among these three glycerol concentrations, the lowest bioconversion cost was obtained when crude glycerol was diluted at 20 g/L. Purification and global production costs were compared with the commercial prices of glycerol and fuel ethanol from corn and sugarcane. Purification costs of raw glycerol were lower than previously reported values due to the methanol recovery. Global production costs for fuel ethanol from glycerol were lower than the reported values for corn-based production and higher than those for cane-based production.     

Comparative analysis for power generation and ethanol production from sugarcane residual biomass in Brazil

This work compares the technical, economic and environmental (GHG emissions mitigation) performance of power generation and ethanol production from sugarcane residual biomass, considering conversion plants adjacent to a sugarcane mill in Brazil. Systems performances were simulated for a projected enzymatic saccharification co-fermentation plant (Ethanol option) and for a commercial steam-Rankine power plant (Electricity option). Surplus bagasse from the mill would be used as fuel/raw material for conversion, while cane trash collected from the field would be used as supplementary fuel at the mill. For the Electricity option, the sugarcane biorefinery (mill+adjacent plant) would produce 91 L of ethanol per tonne of cane and export 130 kWh/t of cane, while for the Ethanol option the total ethanol production would be 124 L/t of cane with an electricity surplus of 50 kWh/t cane. The return on investment (ROI) related to the biochemical conversion route was 15.9%, compared with 23.2% for the power plant, for the conditions in Brazil. Considering the GHG emissions mitigation, the environmentally preferred option is the biochemical conversion route: the net avoided emissions associated to the adjacent plants are estimated to be 493 and 781 kgCO₂eq/t of dry bagasse for the Electricity and Ethanol options, respectively.     

车用乙醇汽油在我国推广应用的现状分析及对策

介绍了我国推广使用车用乙醇汽油现状,分析了车用乙醇汽油在我国推广应用中存在的问题,并提出了相应的对策和建议。     

Investigation of natural convection in convergent vertical channels

Using air as the working fluid, natural convection heat transfer in a uniform wall temperature convergent vertical channel has been investigated numerically. The investigation encompassed half angles of convergence between 0° (parallel-walled channel) and 10° and the solutions were performed for (S/L) Ra_s range of 1 to 2 × 10⁴. In order to find a correlation format which will merge the convergent channel results for low Rayleigh number ranges (Ra′ < 10²) with those for the parallel-walled channel ones, the minimum (S_min), mean (S_avg), and maximum (S_max) interval spacing between channel walls were used as characteristic dimensions. It was found that merging was best achieved by the use of maximum interval spacing (S_max) as the characteristic dimension. These numerical findings agree with those for high Rayleigh number ranges (RA′ > 10²) reported in the literature.     

Calculation of Vertical Mixing in Plane Turbulent Buoyant Jets on the Basis of the Algebraic Model of Turbulence

An algebraic model of turbulence,involving buoyancy forces,is used for calculating velocity and temperaturefields in plane turbulent vertical jets in a non-homogeneous stagnant medium.A new approach to the solution ofthe governing system of partial differential equations (continuity,conservation of momentum,heat (buoyancy),turbulent kinetic energy,dissipation rate and mean quadratic temperature fluctuation) is suggested which isbased on the introduction of mathematical variables.Comparison is made between the results of the presentcalculations with experimental and numerical data of other authors.     

A model for industrial production of fuel grade ethanol from sugar beets

In this work we describe a model for industrial production of low cost ethanol from sugar beets. Care is taken to cover the energy needs of the factory in part by using dry pulp as fuel and in part by solar energy, using suitable solar collectors. Also, care is taken for recovery of rejected energy of vinasse, and we propose the use of one distillation column, instead of three column distillation plants which are used for the production of pure ethanol. A method of high fermentation rate, for reduction of cost, is proposed, and the rejected yeast per day from Laval separators. is processed as an animal protein food (8 kg pressed yeast per 1001 spirit). The mass and energy balance is given and a cost analysis of spirit production in current prices. This cost is 25.0 Dr or $0.50 per 1 (1$ - 50 Dr).     

生物质合成气发酵生产乙醇的工艺分析

介绍了生物质合成气发酵制备乙醇的工艺过程。采用Aspen plus软件对工艺过程建立模型,模拟计算乙醇的产量。针对影响乙醇产量的主要参数进行了灵敏度分析,结果表明:气化过程中氧气与干生物质质量比对乙醇产量影响显著,且比值为0.4时,乙醇产量最大;而气化过程中过多蒸汽的加入会降低乙醇产量;发酵过程中CO和H2转化率的提高有利于乙醇产量的增加。     

Full chain energy analysis of fuel ethanol from cane molasses in Thailand

An analysis of energy performance and supply potential was performed to evaluate molasses utilization for fuel ethanol in Thailand. The Thai government recently has set up a production target of 1.925 million litres a day of sugar-based ethanol. The molasses-based ethanol (MoE) system involves three main segments: sugar cane cultivation, molasses generation, and ethanol conversion. Negative net energy value found for MoE is a consequence of not utilizing system co-products (e.g. stillage and cane trash) for energy. Taking into account only fossil fuel or petroleum inputs in the production cycle, the energy analysis provides results in favour of ethanol. A positive net energy of 5.95 MJ/L which corresponds to 39% energy gain shows that MoE is efficient as far as its potential to replace fossil fuels is concerned. Another encouraging result is that each MJ of petroleum inputs can produce 6.12 MJ of ethanol fuel. Regarding supply potential, if only the surplus molasses is utilized for ethanol, a shift of 8–10% sugar cane produce to fuel ethanol from its current use in sugar industry could be a probable solution.