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蒸汽渗透作为一种新型膜分离技术,可有效解决生物燃料乙醇生产中发酵产物浓度低、能源消耗量大、污染环境等诸多瓶颈问题。与渗透蒸发相比,蒸汽渗透技术具有分离性能好、进料清洁、能量损耗低、操作弹性大等优点,在燃料乙醇生产领域具备更广阔的应用前景。本文在比较渗透蒸发和气体分离技术的基础上,简述了蒸汽渗透过程的机理和特点。介绍了优先透水膜和优先透醇膜两类应用于燃料乙醇生产不同阶段的蒸汽渗透膜和这两类膜材料当前的研究进展,重点阐述了有机/无机杂化膜在成膜方法、杂化材料选择等方面的最新成果。回顾了蒸汽渗透在乙醇脱水方面的工业应用成果,指出该技术在发酵原位分离乙醇和替代精馏工艺方面所具有的优势,探讨了与固态发酵技术相结合进行一次相变生产燃料乙醇工艺实现的可能性,并提出未来亟待研究和解决的问题,为蒸汽渗透技术在燃料乙醇生产领域大规模发展提供参考。 相似文献
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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。 相似文献
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《精细化工原料及中间体》2014,(3)
正吉林石化研究院和北京化工大学合作承担的利用蒸汽渗透技术实现生物质燃料乙醇的原位发酵-分离过程研究项目通过了中国石油科技管理部组织的专家验收。采用该项目成果建设的乙醇发酵-蒸汽渗透耦合中试装置评价表明:渗透液中乙醇浓度在340~480g/L,发酵液中乙醇浓度保持在54~66g/L,分离性能稳定,效果显著,各项指标均达到要求。该项目组在国内首次提出了一种利用蒸汽渗透技术原位分离乙醇的方法,将生物乙醇发酵过程与蒸汽渗透技术相 相似文献
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超滤技术在化肥生产中的应用 总被引:2,自引:1,他引:1
对超滤技术在化肥企业中的应用情况及效果进行了介绍分析,证明此技术用于化肥生产过程的分离、净化非常有效,尤其适合降低合成塔进口气氨含量及油分等。文章最后列出了超滤技术在化肥装置的应用并对应注意的问题进行了介绍。 相似文献
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作为一种可再生的清洁能源,燃料乙醇的开发利用备受关注,对其发酵工艺的研究也日益深入。近年来,补料发酵工艺逐渐应用于燃料乙醇的生产研究中,并以其降低基质抑制和减轻纤维素稀酸水解液中有毒成分的影响等优点而显示了良好的发展潜力,但由于发酵过程的复杂性和对补料控制策略的研究尚不深入等存在的问题,使该技术在燃料乙醇规模化生产中的应用受到制约。本文介绍了国内外乙醇补料发酵研究的主要进展,着重概述补料发酵技术在乙醇两大重要发酵工艺——纤维素乙醇工艺和超高浓度乙醇发酵工艺中的应用以及补料调控策略等,并提出该领域进一步研究应留意的方向,如应加强乙醇补料发酵动力学和控制理论、新型传感器与在线监测技术等方面的研究。 相似文献
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为提高乙醇生产发酵强度,提出了同步汽提闪蒸乙醇发酵新过程。该过程集合了闪蒸发酵和汽提发酵的优点,在发酵的同时能更有效地在位分离乙醇,从而提高发酵强度。通过与普通发酵、闪蒸发酵、汽提发酵等过程进行间歇实验比较,同步闪蒸汽提发酵过程具有发酵强度高的优势;而且,采用耐高温酵母高温发酵、提高通气量、闪蒸罐的进料流速可进一步提高其发酵强度。该过程简单、高效,具有工业应用的潜力。 相似文献
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Nancy Bawa Devin Bear Gordon Hill Catherine Niu William Roesler 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(4):441-446
BACKGROUND: In North America, compared with sugar, starch is a more economical raw material to produce ethanol. Recently low temperature processing of starch granules directly to ethanol has been commercialized. With a view to minimizing process costs while maintaining a satisfactory ethanol yield, an inexpensive medium that does not require the addition of commercial α‐amylase has been developed for low temperature, direct fermentation of starch particles. RESULTS: Compared with an expensive medium that contained both yeast extract and α‐amylase, the inexpensive medium resulted in identical and 10% higher ethanol yields using glucose and starch granules as the raw substrates, respectively, but required longer processing times. Based on the different ingredient prices for expensive and inexpensive media, the operating cost to produce 10 million litres per year of ethanol utilizing simultaneous raw starch hydrolysis and fermentation is reduced over $ 2 million (Cdn) per year when using inexpensive medium. CONCLUSION: The new inexpensive medium and simultaneous raw starch hydrolysis and fermentation is considered the best strategy to produce ethanol directly from starch particles in North America. Copyright © 2009 Society of Chemical Industry 相似文献
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A new cleaner production process for cassava ethanol has been developed, in which the thin stillage by-product was treated initially by anaerobic digestion, and the digestate further processed by hydrogen-form cation exchange resin before being recycled as process water to make mash for the next ethanol fermentation batch. Thuswastewaterwas eliminated and freshwater and energy consumptionwas significantly reduced. To evaluate the new process, ten consecutive batches of ethanol fermentation and anaerobic digestion at lab scale were carried out. Average ethanol production in the recycling batches was 11.43% (v/v) which was similar to the first batch,where deionized (DI)waterwas used as process water. The chemical oxygen demand (COD) removal rate reached 98% and the methane yield was 322 ml per gramof COD removed, suggesting an efficient and stable operation of the anaerobic digestion. In conclusion, the application of the new process can contribute to sustainable development of the cassava ethanol industry. 相似文献
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Kerstin Hoyer Mats Galbe Guido Zacchi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(4):570-577
BACKGROUND: The production of bio‐ethanol from softwood is considered a promising alternative to fossil fuels in Sweden. In order to make fuel ethanol economically competitive with fossil fuels, it is important to reduce the production cost, which can be done by increasing the dry matter content of the fermentation medium, thus reducing the energy demand in the final distillation of the fermentation broth. Running simultaneous saccharification and fermentation (SSF) at higher dry matter content has, however, been found to decrease the ethanol yield. RESULTS: The use of different stirrer types and stirring speeds in the present study has shown to have an influence on the final ethanol yield in SSF with 10% water‐insoluble solids (WIS). Also, higher concentration of pretreatment hydrolysate, i.e., with increased inhibitor concentration, at the same WIS resulted in a decreased ethanol yield. However, despite stirring problems and high inhibitor concentration, ethanol was produced at 12% WIS with an ethanol yield in the SSF step of 81% of the theoretical based on the content of fermentable sugars in the fermentor. CONCLUSION: The decrease in ethanol yield in SSF at high dry matter content has been shown to be a combined effect of increased mass transfer resistance and increased inhibitor concentration in the fermentation broth. Copyright © 2008 Society of Chemical Industry 相似文献
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采用合成气生物发酵法制乙醇具有反应条件温和、产物选择性高、原料来源广泛、低碳可持续发展等优势,是一种具有前景的可再生能源新型生产工艺。文章综述了合成气发酵法制乙醇的微生物种类及对应的适宜操作条件,分析了合成气发酵法制乙醇的Wood-Ljungdahl代谢途径;总结了合成气的广泛来源;分析讨论了过程工艺参数如合成气组成及压力、pH、温度、培养基组分、气液传质对合成气发酵的影响;指出合成气发酵法制乙醇面临的底物传质性能差、乙醇收率低等关键问题,比较了典型反应器在传质方面的差异,归纳了传质强化方法;总结了合成气发酵法制乙醇的工业化进展, 并提出了未来的发展方向。 相似文献
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采用合成气生物发酵法制乙醇具有反应条件温和、产物选择性高、原料来源广泛、低碳可持续发展等优势,是一种具有前景的可再生能源新型生产工艺。文章综述了合成气发酵法制乙醇的微生物种类及对应的适宜操作条件,分析了合成气发酵法制乙醇的Wood-Ljungdahl代谢途径;总结了合成气的广泛来源;分析讨论了过程工艺参数如合成气组成及压力、pH、温度、培养基组分、气液传质对合成气发酵的影响;指出合成气发酵法制乙醇面临的底物传质性能差、乙醇收率低等关键问题,比较了典型反应器在传质方面的差异,归纳了传质强化方法;总结了合成气发酵法制乙醇的工业化进展, 并提出了未来的发展方向。 相似文献
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蒸汽爆破麦草同步糖化发酵转化乙醇的研究 总被引:4,自引:0,他引:4
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%。 相似文献
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介绍了发展绿色节能酒精工业前景 ,并提出了发酵酒精原料综合利用、节能生产工艺和推广应用乙醇汽油、乙醇柴油的建议。 相似文献