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。     

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。     

渗透汽化在生物燃料乙醇制备中的研究进展

渗透汽化作为一种新型的膜分离技术应用于发酵法制备生物燃料乙醇,不但能减少产物对微生物的抑制作用,而且可以脱水制备高纯度燃料乙醇,因而具有显著的优势。本文对渗透汽化在发酵法制备燃料乙醇中所涉及的膜材料、耦合工艺、应用现状和经济评价进行了详细的综述,并对发展趋势作了展望。     

生物质吸附剂在制备燃料乙醇中应用的研究进展

在最近的几十年中,由于能源短缺和环境恶化,生物质燃料乙醇（BFE）因为其所具有的可循环无污染的优点,引起了人们越来越多的关注。但是在生物燃料乙醇的制备过程中,存在着乙醇脱水工艺能量消耗过大的问题。因此优化乙醇脱水过程一直是人们研究的重中之重。本文简述了国内外吸附法分离乙醇和水工艺中使用的吸附剂,指出了生物质吸附剂在燃料乙醇中优于其它吸附剂的特点,重点分析了生物质吸附剂的研究成果及对其的改性研究。分析表明改性后吸附剂不但拥有良好的吸附效果,还可以在吸附操作结束后重新作为发酵制乙醇的原料,以实现资源的充分利用。最后展望了生物质吸附剂在制备燃料乙醇工艺中的发展趋势,即获得更优秀的脱水效果与更完善的循环利用过程。     

玉米燃料乙醇低能耗工业生产新工艺

本团队研发的玉米燃料乙醇低能耗生产新工艺,采用了低温液化、浓醪同步糖化间歇发酵、三塔压差精馏与分子筛脱水工艺和全厂各工段的废热进行余热回收技术,目前已经成功应用于多家燃料乙醇生产企业.以黑龙江鸿展生物科技股份有限公司已经投产的30万吨级燃料乙醇工程项目为例,对比分析了新工艺与传统工艺在技术特点、能耗、产品质量等方面的差...     

蒸汽渗透技术在燃料乙醇生产中的应用研究进展

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。     

透水型分子筛膜在生物燃料乙醇生产中应用的经济性分析

针对生物燃料乙醇生产过程,提出精馏-分子筛膜耦合工艺(膜工艺)进行脱水,并与精馏-分子筛变压吸附工艺进行了比较,结果表明,采用膜工艺可节约蒸汽0. 3 t/t。以年产20万t生物燃料乙醇项目为例,分析了膜通量、膜单价和蒸汽价格对膜工艺综合运行成本的影响,为膜工艺在生物燃料乙醇生产过程中的应用提供了指导。     

燃料乙醇发展现状及思考

自20世纪70年代以来,生物燃料乙醇作为车用燃料的研究和产业化受到广泛重视,被认为是未来最重要的可再生燃料之一。本文介绍了燃料乙醇的发展概况,综述了近年来国内外研究开发历程、产业政策和最新进展,对化学合成乙醇路线（合成气催化制乙醇、乙酸加氢制乙醇工艺）和生物发酵制乙醇路线（粮食发酵、非粮原料发酵、合成气发酵工艺）的技术特点、纤维素燃料乙醇产业化存在的困难和问题进行了分析,并对影响燃料乙醇产业发展的因素进行了分析,提出了我国燃料乙醇技术研发和产业发展的相关建议,认为我国应加强非粮原料供应体系建设,积极进行技术研发,加强工业示范并优化燃料乙醇使用环节,促进非粮燃料乙醇产业发展。     

燃料乙醇的研究与展望

通过介绍发酵法,乙醇脱水制造燃料乙醇的方法,正确定位燃科乙醇足油品的优良品质改良剂,燃料乙醇不足"油",是一种可再生能源,燃料乙醇的辛烷值高抗爆性能好,且能减少多大气的污染,可作为新的燃料替代品.     

利用CBP发酵纤维素生产燃料乙醇的研究进展

介绍了联合生物加工(CBP)技术,并阐述通过该技术对发酵纤维素生产燃料乙醇的工艺进行技术改造,为利用纤维素低成本生产燃料乙醇提供了有效途径.     

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.     

秸秆制燃料乙醇工艺技术

论述了当前国内秸秆制燃料乙醇的工艺技术过程,包括原料预处理、水解及发酵,并且展望了未来秸秆制乙醇技术的发展方向。纤维乙醇生产示范研究是未来产业化过程中一种必不可少的探索,也是实现其技术工程化的重要基础和平台．     

The Chatham demonstration: From design to operation of a 20 m/d membrane-based ethanol dewatering system

Distillation/dehydration represents the largest fraction of the energy used in the production of ethanol. The Siftek™ technology introduced in this paper carries the potential of reducing energy consumption of distillation/dehydration by up to 50% through the single pass removal of water from the water/ethanol stream at the beer column outlet, using a novel membrane process.Siftek™ is a polymeric membrane that can be used to dry ethanol in the vapor phase. The membrane preferentially permeates water over ethanol in a continuous process. Energy reductions are obtained because this membrane is well suited to remove large quantities of water without phase change.The Siftek™ technology has been piloted since August 2006 in a Greenfield Ethanol plant in Tiverton, Ontario, Canada. The Tiverton unit has a capacity of 1 m³/d and has been producing fuel ethanol from a feed containing between 75 and 90 wt.% ethanol in a single stage system.Based on the successful operation of the pilot, it was decided to scale-up the technology. A two-stage membrane system with a capacity of 20 m³/d was built for the Greenfield Ethanol plant in Chatham, Ontario, Canada. The unit is equipped with full-scale commercial membrane modules and is capable of treating a beer-column feed containing 60-70 wt.% ethanol, producing > 99 wt.% fuel-grade ethanol.     

Simultaneous saccharification and fermentation of sweet potato powder for the production of ethanol under conditions of very high gravity

Due to its merits of drought tolerance and high yield, sweet potatoes are widely considered as a potential alterative feedstock for bioethanol production. Very high gravity (VHG) technology is an effective strategy for improving the efficiency of ethanol fermentation from starch materials. However, this technology has rarely been applied to sweet potatoes because of the high viscosity of their liquid mash. To overcome this problem, cellulase was added to reduce the high viscosity, and the optimal dosage and treatment time were 8 U/g (sweet potato powder) and 1 h, respectively. After pretreatment by cellulase, the viscosity of the VHG sweet potato mash (containing 284.2 g/L of carbohydrates) was reduced by 81%. After liquefaction and simultaneous saccharification and fermentation (SSF), the final ethanol concentration reached 15.5% (v/v), and the total sugar conversion and ethanol yields were 96.5% and 87.8%, respectively.     

乙醇制乙烯技术现状及展望

介绍了乙醇脱水制乙烯生产工艺的技术发展现状,涉及催化剂研制应用现状、不同生产工艺的技术经济比较等,并指出了在现有能源需求背景下,发展乙醇法制乙烯的重要意义及应用前景。     

Reducing the energy demand of corn‐based fuel ethanol through salt extractive distillation enabled by electrodialysis

The thermal energy demand for producing fuel ethanol from the fermentation broth of a contemporary corn‐to‐fuel ethanol plant in the U.S. is largely satisfied by combustion of fossil fuels, which impacts the possible economical and environmental advantages of bioethanol over fossil fuels. To reduce the thermal energy demand for producing fuel ethanol, a process integrating salt extractive distillation—enabled by a new scheme of electrodialysis and spray drying for salt recovery—in the water‐ethanol separation train of a contemporary corn‐to‐fuel ethanol plant is investigated. Process simulation using Aspen Plus® 2006.5, with the electrolyte nonrandom two liquid Redlich‐Kwong property method to model the vapor liquid equilibrium of the water‐ethanol‐salt system, was carried out. The integrated salt extractive distillation process may provide a thermal energy savings of about 30%, when compared with the contemporary process for separating fuel ethanol from the beer column distillate. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

燃料乙醇制备方法研究进展

综述了燃料乙醇制备方法的研究进展。介绍了溶盐精馏法、萃取精馏法、加盐萃取精馏法、吸附法及渗透汽化法等多种乙醇脱水提纯的方法,并对上述方法作用机理及特点进行对比。其中,吸附法能在常温常压下吸附脱除乙醇中的水,如能通过研究,进一步降低再生成本,是一项具有广阔前景的燃料乙醇制备技术。     

Cell‐free ethanol production: the future of fuel ethanol?

The production of fuel ethanol from renewable resources as an economically viable alternative to gasoline is currently the subject of much research. Most studies seek to improve process efficiency by increasing the rate of ethanol production; ultimately, this approach will be limited by the selected ethanol‐producing microorganism. Cell‐free ethanol production, using only the enzymes involved in the conversion of glucose to ethanol, may offer a practical and beneficial alternative. Mathematical modeling of such a system has suggested that a cell‐free process should be capable of producing ethanol much more efficiently than the microbial based process. This finding along with other potential benefits of a microorganism‐free process suggests that a cell‐free process might significantly improve the economy of fuel ethanol production and is a worthy target for further research. Copyright © 2007 Society of Chemical Industry