落实科学发展观 大力发展替代能源 防止盲目发展与投资过热 煤基能源化工将成为我国能源格局重要部分——发展过热 引发深思——对我国煤基能源化工品发展的调查与思考之一

当前,国际油价高企,作为替代能源的煤化工产品正日益受到各方关注。在全球对替代化工原料和替代能源的需求越发迫切的背景下,煤化工产品将成为我国能源结构的重要组成部分。     

能源替代前行中面临挑战

由于石油价格的持续高位,能源替代问题一直是人们共同关注的首要问题,由此引发了国内煤化工热和生物能源之热.从越来越激烈的能源之争、越来越热的煤变油项目阐述了关于能源替代战略的问题,介绍了作为汽车燃料替代能源的甲醇生产的原料、规模、市场的问题,乙醇生产的原料、技术和生态的问题,从原料、经济、毒性几方面分析了甲醇、乙醇作为石油替代能源的优势与劣势.     

多元化替代石油能源的技术发展及趋势

分析了世界多元化替代石油能源的技术现状及发展趋势,以及目前石油高价位下开展替代能源多元化开发的重要战略意义。介绍了国内外开发生物柴油、燃料乙醇、天然气制油、煤制油等多元化替代资源的技术发展现状、存在问题。并提出中国多元化能源替代石油技术发展的思路。     

对我国能源替代战略的思考

结合国内外替代能源的开发应用情况,对目前我国替代能源项目,包括煤变油、甲醇、乙醇、生物柴油等,从原料、经济性、技术、环境污染等方面进行了较为深入的分析,以期引起正在建设和准备建设替代能源项目的地方政府和企业的思考。     

对我国能源替代战略的思考

结合国内外替代能源的开发应用情况,对目前我国替代能源项目,包括煤变油、甲醇、乙醇、生物柴油等,从原料、经济性、技术、环境污染等方面进行了较为深入的分析,以期引起正在建设和准备建设替代能源项目的地方政府和企业的思考.     

中国企业积极寻求应用于生产经营的替代能源——道康宁公司分享针对企业对待替代能源态度的调研结果

随着全球能源价格持续攀升，我国企业正在积极寻求可持续性的替代能源解决方案。根据哈里斯互动调查（Harris Interactive）公司受道康宁公司委托进行的一项关于替代能源趋势的全球性研究显示．我国大约有40％的企业已经开始实施替代能源技术或正在采取积极措施来对各自业务的替代能源方案进行研究。     

从生物燃料热看新能源的开发

近年来,在国际原油价格不断上涨、国内对石油需求量日益增长的情况下,各种新型替代能源的推广和普及对缓解我国石油供应紧张具有重要意义。寻找新型可替代能源,成为中国未来能源战略的关键。     

新能源趋势下看各国能源政策

据有关机构预测,目前世界可替代能源正以每年25%的速度增长.截止2030年,可替代能源将占全球能源市场70%的份额.     

生物燃料热潮与新能源的开发

近年来,在国际原油价格不断上涨、国内对石油需求量日益增长的情况下,各种新型能源的推广和普及,对替代和缓解我国石油不足具有重要意义.寻找新型可替代能源成为中国未来能源战略的关键.     

上宏鞋业：清洁能源替代成就“绿色”鞋企

上海上宏鞋业有限公司根据上海市《燃煤（重油）锅炉清洁能源替代工作方案》的要求,积极开展清洁能源替代工程的建设,创建＂绿色＂胶鞋生产企业。 在替代工程实施前,上宏鞋业平均每天耗煤4吨,每月耗煤100吨,全年耗煤1200吨,折合标煤857吨。清洁能源替代工程建成后,燃煤锅炉停运,预计每年可减少二氧化碳排放1251吨、二氧化硫10.3吨、氮氧化物6吨和烟尘3.4吨。     

木薯酒精渣的预处理及补料同步糖化发酵制取乙醇

木薯酒精渣的处置是制约木薯燃料乙醇大规模产业化的问题之一。本文立足于探索木薯酒精渣利用途径,分析了木薯酒精渣的主要成分,对比了氨水、氢氧化钠、氨水组合稀硫酸3种预处理方式对于木薯酒精渣纤维素和木素含量及纤维素酶水解效率的影响,分析了处理前后木薯酒精渣的表面结构及纤维素结晶度,并以氨水处理后的木薯酒精渣为底物,进行了同步糖化发酵。结果表明,3种预处理方法中组合预处理能更好地增加纤维素含量和提高纤维素酶水解效率,与未处理原料相比,组合预处理后纤维素含量增加了111.26%,木素下降了35.05%,酶水解72h纤维素转化率从42.10%增加到61.71%。氨水预处理后,原料的木素含量降低,处理后木薯酒精渣的表面变得更加粗糙,纤维素结晶度有所增加,以氨水处理后的木薯酒精渣为底物进行分批补料同步糖化发酵,当初始底物浓度为100.0g/L,分别在20h、40h、60h进行补料至最终底物浓度为400.0g/L时,发酵120h乙醇浓度达到51.0g/L。     

FED-BATCH SIMULTANEOUS SACCHARIFICATION AND FERMENTATION OF MICROWAVE/ACID/ALKALI/H2O2 PRETREATED RICE STRAW FOR PRODUCTION OF ETHANOL

The batch simultaneous saccharification and fermentation (SSF) of microwave/acid/alkali/H₂O₂ pretreated rice straw to ethanol was optimized using cellulase from Trichoderma reesei and Saccharomyces cerevisiae YC-097 cells prior to the fed-batch SSF studies. The batch SSF optima were 10% w/v substrate, 40°C, 15 mg cellulase/g substrate, initial pH 5.3, and 72 hours. Under the optimum conditions the ethanol concentration and its yield were 29.1 g/L and 61.3% respectively. Based on the optimal batch SSF, the fed-batch SSF was investigated and its operation parameters were optimized. Under its optimal conditions the ethanol concentration reached 57.3 g/L, while its productivity and yield were only slightly less than those in the batch SSF. This suggests that fed-batch SSF is a potential operation mode for effective ethanol production from microwave/acid/alkali/H₂O₂ pretreated rice straw.     

蒸汽爆破麦草同步糖化发酵转化乙醇的研究

近年来对木质生物资源同步糖化发酵转化乙醇的研究较多,但是,麦草同步糖化发酵转化乙醇的最佳工艺条件还未确定。文中采用正交试验设计的方法,对在混合酶(纤维素酶Celluclast 1.5 1,β-葡萄糖苷酶Novozym 188)与酿酒酵母菌作用下,稀硫酸催化的蒸汽爆破麦草原料同步糖化发酵转化乙醇的工艺条件进行研究,详细讨论了反应温度、底物质量浓度、发酵液pH值、纤维素酶浓度对乙醇质量浓度和得率的影响。结果表明,工艺条件对乙醇质量浓度和得率的影响程度由高到低依次为:底物质量浓度、纤维素酶浓度、发酵液pH值、反应温度。最佳工艺条件为反应温度35℃,底物质量浓度100 g/L,发酵液pH值5.0,纤维素酶浓度30 FPU/g。在此条件下,随着反应时间的延长,乙醇质量浓度持续上升。反应72 h后,乙醇质量浓度和得率分别达到22.7 g/L和65.8%。     

FED-BATCH SIMULTANEOUS SACCHARIFICATION AND FERMENTATION OF MICROWAVE/ACID/ALKALI/H2O2 PRETREATED RICE STRAW FOR PRODUCTION OF ETHANOL

The batch simultaneous saccharification and fermentation (SSF) of microwave/acid/alkali/H₂O₂ pretreated rice straw to ethanol was optimized using cellulase from Trichoderma reesei and Saccharomyces cerevisiae YC-097 cells prior to the fed-batch SSF studies. The batch SSF optima were 10% w/v substrate, 40°C, 15 mg cellulase/g substrate, initial pH 5.3, and 72 hours. Under the optimum conditions the ethanol concentration and its yield were 29.1 g/L and 61.3% respectively. Based on the optimal batch SSF, the fed-batch SSF was investigated and its operation parameters were optimized. Under its optimal conditions the ethanol concentration reached 57.3 g/L, while its productivity and yield were only slightly less than those in the batch SSF. This suggests that fed-batch SSF is a potential operation mode for effective ethanol production from microwave/acid/alkali/H₂O₂ pretreated rice straw.     

Second-generation ethanol production from steam exploded barley straw by Kluyveromyces marxianus CECT 10875

Barley straw is nowadays being considered a potential lignocellulosic raw material for fuel-ethanol production as an alternative to starch- or sugar-containing feedstock. In this work, several configuration strategies for ethanol production from steam-exploded barley straw by Kluyveromyces marxianus CECT 10875 have been studied with the aim of obtaining higher ethanol concentrations.Different substrate loading (2-15%, w/v) were studied during enzymatic hydrolysis. The xylanase contribution on glucose production and glucan conversion at different substrate loading was also investigated. In addition, three different process configurations, separate hydrolysis and fermentation, simultaneous saccharification and fermentation and presaccharification and simultaneous saccharification, were compared at different water insoluble solids concentration (5%, 10% and 15%). The influence of xylanase addition on the ethanol yield was studied as well.Results show that endo-xylanases improved glucan conversion and ethanol yield compared with a standard enzymatic mixture, markedly at low substrate concentration. The positive effect of added xylanase was most evident at early stages of enzymatic hydrolysis. Regarding process configurations for the period of 72 h, SSF with endo-xylanases provided the best ethanol yield, nearly 70%, for 10% WIS. Nonetheless, the higher ethanol concentration, 29.4 g/l, was obtained at 15% WIS.     

乙醇发酵原位分离产物耦合方法研究进展

乙醇发酵过程存在明显的产物抑制现象,严重制约了乙醇产率的提高。乙醇发酵与产物分离的耦合可有效解决这一难题,目前乙醇发酵耦合产物分离的方法主要有乙醇气提发酵、乙醇真空发酵、乙醇吸附发酵、乙醇萃取发酵、乙醇膜分离发酵等。作者主要概述了各种乙醇发酵耦合产物分离方法的研究进展,并对今后乙醇发酵耦合产物分离研究开发提出了展望。     

蛹虫草菌深层液体发酵耦合大孔树脂吸附高效生产虫草素

虫草素是一种核苷类抗生素,具有抗癌、抗肿瘤等活性,主要由蛹虫草菌液体发酵生产,然而低产量限制了其应用。考虑到高浓度虫草素积累对其生物合成过程产生强烈反馈抑制,提出了应用发酵分离耦合技术移除部分虫草素、弱化反馈抑制作用以提高虫草素产量的策略。通过静态吸附实验,筛选出虫草素吸附和解吸性能良好的大孔树脂NKA-Ⅱ,并优化了大孔树脂使用量（60 g·L^-1）、吸附温度（37℃）和解吸剂种类（100%乙醇）。在30 g·L^-1葡萄糖的分批发酵体系中,经过两次树脂吸附,发酵21 d后虫草素产量达到644.50 mg·L^-1,较对照组提高32.07%;随后,将树脂吸附分离策略应用于补料分批发酵体系,虫草素产量达到787.50 mg·L^-1,较对照组提高35.78%。这些结果表明,将虫草素液体发酵与大孔树脂吸附分离耦合,有效弱化了虫草素反馈抑制,显著提高虫草素产量,为虫草素高效生产分离提供了新思路。     

木质纤维生物质同步糖化发酵(SSF)生产乙醇的研究进展

综述了有关木质纤维生物质原料同步糖化发酵生产乙醇的最新研究进展和未来发展方向:同步糖化发酵是一种用于从木质纤维原料生产乙醇的工艺过程,此工艺的优点是酶水解与发酵同时进行,可以减少最终产物对酶水解的抑制作用,并减少投资成本,是最具发展潜力和优势的工艺之一。近年来在优化预处理工艺、降低纤维素酶成本以及己糖戊糖协同发酵等方面的研究都取得了长足的进步,其中以小麦秸秆为原料进行同步糖化发酵所得到的乙醇浓度接近40g/L。     

生物乙醇原位分离技术的研究进展

生物乙醇是一种重要的可再生生物燃料,使用生物乙醇可大幅减少温室气体排放。为了建立更高效低能耗的生物乙醇回收工艺,原位分离（ISPR）技术应运而生。本文综述了近年来乙醇原位分离的研究进展,从原理及应用等进行多方面详细地介绍,包括气提、真空发酵、吸附、液-液萃取、渗透汽化、膜蒸馏等分离技术。针对分离性能、能耗成本等问题分析了不同分离技术耦合发酵过程的优势及不足,重点回顾了以渗透汽化为代表的膜分离技术,总结了渗透汽化膜材料的选择以及膜的制备方法,旨在提升乙醇分离膜性能优化乙醇分离工艺。为整合不同分离技术的特点及优势,聚焦多级耦合分离系统的开发对各级分离技术联用的性能及潜力进行剖析与评价,并在此基础上研判其发展前景。     

Different process configurations for bioethanol production from pretreated olive pruning biomass

BACKGROUND: In Mediterranean countries, olive tree pruning provides a widely available renewable agricultural residue with, currently, no industrial application. This residue could provide feedstock for the bioethanol industry. In the present study, olive tree pruning biomass pretreated with both ‘liquid hot water’ and ‘dilute‐sulfuric acid’ was tested as a substrate for ethanol production. Three different process configurations, separate hydrolysis and fermentation (SHF), simultaneous saccharification, fermentation and prehydrolysis (PSSF), and simultaneous saccharification and fermentation (SSF), were compared at different water‐insoluble solids concentrations. RESULTS: High ethanol concentration of about 3.7% (v/v) was obtained by separate hydrolysis and fermentation or prehydrolysis and simultaneous saccharification and fermentation of liquid hot water pretreated at 23% (w/w) substrate loading. CONCLUSION: The nature of the pretreated residue allows high substrate concentration (≥17% w/w) to be used in the enzymatic hydrolysis step. Substrate loading of 17% DM has been shown to provide a compromise between hydrolysis efficiency and glucose concentrations for the same enzyme/substrate ratio. Prehydrolysis prior to simultaneous saccharification and fermentation facilitated SSF performance at high substrate loading on liquid hot water pretreated olive pruning residue. This effect was not observed with dilute‐acid pretreated substrate. Copyright © 2011 Society of Chemical Industry