燃料乙醇脱水工艺的研究与展望

伴随人类环境保护意识的进一步提升,清洁能源的应用逐渐普及化,乙醇燃料的脱水提纯处理工艺已成为清洁燃料应用的重要方面。基于此,本文在对乙醇燃料脱水工艺进行整体把握的基础之上,对燃料乙醇脱水主要工艺处理技术进行了详细介绍。     

乙醇脱水工艺改进

应用干燥的纳型阳离子交换树脂作工业乙醇脱水剂,并就接触时间,杂质来源等问题进行分析并提出改进意见,经实际应用,获提高收纺３０％,降低能耗３０％。     

甘薯高效乙醇生产技术通过鉴定

2010年8月31日,四川省科技厅组织专家对中国科学院成都生物研究所完成的甘薯高效乙醇生产技术进行了成果鉴定。 该研究通过高效乙醇发酵菌株、降黏技术体系、鲜甘薯快速乙醇发酵和鲜甘薯高浓度乙醇发酵等关键技术模块的系统集成,形成了乙醇转化率高,能耗低、生产效率高、季节适应性好、原料适应性广、经济性强,符合清洁生产机制的燃料乙醇高效转化技术,为具有我国特色的甘薯燃料乙醇发展提供了技术支持。     

现代燃料乙醇生产技术研究(I)

燃料乙醇以其可再生特点、可替代石油和具备环保功能的特点被选为优良的替代能源,得到大家的高度重视.大规模成套生产工艺;木质纤维素的预处理;现代发酵技术和发酵水溶液的脱水是现代燃料乙醇生产技术的重要内容,成为生物能源产业的研究重点和发展方向.     

燃料乙醇的生产进展和应用探讨

介绍了乙醇的生产技术研究现状、燃料乙醇的生产新工艺和发展现状：对比分析了国内外燃料乙醇标准：讨论了我国应用燃料乙醇生产乙醇汽油的补贴计算方法及开发乙醇柴油的前景，提出以体积为计价单位、扩大原料来源，搞好综合利用、降低生产成本的建议。     

乙醇脱水的木薯粉吸附性能研究

使用恒温固定吸附床对乙醇蒸汽脱水的术薯粉吸附剂的气相选择吸附性能进行研究。乙醇原料液的浓度为75％～95％（质量百分数）,使用干燥过的木薯粉作为吸4;什剂,分别测得吸附床不同位置处、不同表观速率、不同吸附剂粒度和不同温度时的乙醇蒸汽的透过曲线并进行了分析。通过木薯粉吸附最终可获得99．7％（质量百分数）的无水乙醇。     

微藻生物质生产燃料乙醇技术进展

燃料乙醇是燃烧清洁的高辛烷值燃料,是可再生能源,也是优良的燃油改善剂。微藻是一种高光合效率、高生物量产值的生物质资源,部分微藻经光合作用可在胞内积累大量淀粉和纤维素,是制备燃料乙醇的良好原料。利用微藻生物质生产燃料乙醇,对于缓解石油资源日益紧缺的现状及解决一系列由温室气体引起的环境问题具有乐观的应用前景。介绍了微藻作为生物质供应的特性,综述了国内外对于微藻生产燃料乙醇的技术进展、现存在问题及未来的发展前景。     

用于乙醇脱水的生物质吸附性能

The adsorption capability of paddy flour and maize flour for gaseous phase selective adsorption for ethanol dehydration was investigated via a bench-test fixed-bed adsorber at constant temperature. Ethanol concentration in the feed was 93.4% (mass) and each of the dried biomass was used as adsorbent, and breakthrough curves and temperature distribution in adsorptive bed were obtained for different bed depths,superficial velocities, granularities of adsorbent and temperatures. Bed pressure drop curves for different bed depths and superficial velocities were also measured. A product of ethanol purity of 99.5% (mass) could be obtained through both kinds of biomass adsorbent. When 99.5% (mass) of ethanol purity is defined as the breakthrough point, the production capacity for either adsorbent was within 0.0915-0.2256 (gram product/gram adsorbent). Tests on pure ethanol adsorption were also performed to extrapolate the selectivity of both adsorbents.     

乙醇脱水工艺改进

应用干燥的纳型阳离子交换树脂作工业乙醇脱水剂,并就接触时间,杂质来源等问题进行分析并提出改进意见。经实际应用,获提高收率３０％,降低能耗３０％     

我国燃料乙醇生产技术现状与发展前景分析

资源和能源是人类社会生存和发展的永恒需求,当前用以支撑全球经济发展的石油资源及能源供应正面临严峻挑战。燃料乙醇作为新的可再生的燃料替代品,可直接用作液体燃料或者同汽油混合使用,减少对不可再生能源——石油的依赖,保障本国的能源安全而日益受到各国的重视。作者介绍了国内外燃料乙醇生产技术概况与研究发展现状,分析了我国发展非粮燃料乙醇的必要性及存在的技术关键和发展前景。指出从长远来看,生产纤维质原料燃料乙醇是燃料乙醇发展的根本出路。     

燃料乙醇发展现状和前景展望

介绍了国内外燃料乙醇的发展现状以及我国对于发展燃料乙醇的相关政策,从成本、原料、粮食安全、市场及经济性方面进行了分析,建议应借助人大立法,保证燃料乙醇推广的顺利进行;政府应制定补贴、免征税收等政策并及时落实;积极推进燃料乙醇新技术的开发工作;扩大燃料乙醇应用范围,推进燃料乙醇的应用进程;开展乙醇化工的研究。     

Ethanol production from sweet sorghum residual

In this work, the ethanol production from sweet sorghum residue was studied. Sweet sorghum residue was hydrolyzed with phosphoric acid under mild conditions. The liquid hydrolysate was fermented by Pachysolen tannophilus, and the hydrolysis residue was fermented by the simultaneous saccharification and fermentation (SSF) using Saccharomyces cerevisiae with cellulase (60 FPU/g dry materials). Orthogonal experiments were carried out to investigate the effects of main reaction condition factors, such as temperature, acid concentration, time and dry-matter content, on the reducing sugar yield. The results show that the optimal reaction conditions should be 120°C, 80 g/L, 80 min and 10%, respectively. Under these conditions, 0.3024 g reducing sugar/g dry material was obtained. The liquid hydrolysate was then fermented by P.tannophilus with the highest ethanol concentration of 14.5 g/L. At a water-insoluble solid concentration of 5%, 5.4 g/L ethanol was obtained after 12 h of SSF. The total ethanol yield was 0.147 g/g dry material, which would be beneficial for the application of ethanol production from sweet sorghum residue. __________ Translated from Journal of Beijing University of Chemical Technology, 2007, 34(6): 637-639, 652 [译自: 北京化工大学学报]     

中国生物燃料乙醇产业发展现状、存在问题及政策建议

燃料乙醇等生物质能源由于其技术的可实现性、资源的可持续性以及环境的友好性已经成为各国替代能源的重要发展方向。本文阐述了燃料乙醇产业发展的历程和现状,指出燃料乙醇产业发展中存在的问题,并提出了解决问题的对策。     

Effects of pretreatments on properties of microwave-vacuum drying of sweet potato slices

Abstract

Pretreatments of blanching (BL); osmotic dehydration at 35°Brix of sucrose (OD); ultrasound in distilled water (UD), and ultrasound-assisted osmotic dehydration (UO) were carried out for microwave-vacuum drying (MVD) orange- and purple-flesh sweet potato slices, and effects on their properties were investigated in this study. UO had improvements effects on water loss, solid gain, and relaxation time of the samples compared to other pretreatments. Low-field nuclear magnetic resonance results offered a view of water state concerning the effects of different pretreatments on sweet potato. UD treatment following by BL showed a long relaxation time corresponding to the weaker degree of bound hydrogen proton or the greater freedom degree of hydrogen comparing to other pretreated samples. Differential scanning calorimetry parameters appeared to be sensitive to pretreatments by increased Tg value compared to blanched sample. The value of Tg shows that it does not depend only of the water content but also on the experimental conditions (pretreatments). The dried sweet potato exhibited amorphous structures as evidenced by the X-ray diffractograms due to the BL treatment and MVD. Concentration of total phenolics and anthocyanins were high in purple sweet potatoes, whereas content of vitamin C and total carotenoid were high in orange ones. Application of UO is suitable for retention of bioactive compound and stability of MVD sweet potato slices.     

Ultrasound-assisted osmotic process on quality of microwave vacuum drying sweet potato

The effects of pretreatment before microwave vacuum drying (MVD) on texture, color, expansion, rehydration, drying rate, microstructure, sensory evaluation, and other properties of sweet potato were investigated in this study. The pretreatment consisted in five processing conditions, using blanching; osmotic dehydration at 35°Brix of sucrose (OD); ultrasound in distilled water (US); ultrasound in distilled water before osmotic dehydration (US?+?OD), and ultrasound-assisted osmotic dehydration (USOD). Pretreatments of sweet potato before MVD have shown success in reducing drying time with US treatment relatively more effective regarding drying time than other treatments. Compared with other treatments, US showed the highest rehydration ratio values. The osmotic group pretreatment exhibited a pronounced effect on water loss and solid gain, improved the color, aroma, and taste of dried sweet potato, whereas sucrose impregnation resulted in a hard texture observed with OD sample. USOD samples had a higher expansion ratio, lower hardness and color difference values, appeared less cell damaged, and recorded better overall quality than the other samples. There was a slight difference between USOD and US?+?OD samples. Combining osmotic dehydration with ultrasound as a pretreatment can significantly accelerate the heat transfer rate, reducing the dried time accordingly and increasing energy efficiency.     

生物基燃料乙醇生产工艺的能耗分析与节能技术综述

针对如何高效、经济和可持续发展生物质液体燃料这一问题,考察了淀粉质原料生产燃料乙醇的整个流程,从原料预处理到酒精脱水,尤其针对蒸馏、蒸煮液化等耗能较大的阶段,对不同的生产工艺技术进行了能耗比较,分析了不同的节能技术。通过大量的数据分析评述了最佳的技术路线,为燃料乙醇生产系统的节能降耗提出建议。     

云南省燃料乙醇产业发展现状与对策

以云南省燃料乙醇产业发展形势、资源潜力、区位优势为背景,阐述了云南省燃料乙醇产业发展的现状。提出从政策保障角度,云南省燃料乙醇产业发展可从积极争取国家燃料乙醇试点省份,成立专门的燃料乙醇协调部门、建立专项补贴资金体系,形成一定规模的燃料乙醇试点、优先拉通产业链、为燃料乙醇推广形成示范效应等对策方面加以完善;从原料保障角度,可从保障甘蔗原料供应、扩大薯类原料种植面积、积极促进土地流转、建立集约化种植管理模式、开发境外种植基地等方面加以提升。最后提出云南省燃料乙醇产业发展措施,整合省内中小型乙醇生产企业以形成规模效应,综合发展以形成产业链并降低燃料乙醇生产成本。