蔗渣闪爆处理及其黄原酸化物的制备和应用

采用热蒸汽适度闪爆及稀碱洗涤等预处理技术对蔗渣进行纯化和活化,利用处理后的蔗渣纤维素合成纤维素基黄原酸酯,对其在水处理中的应用进行了研究。研究优化了闪爆处理的工艺条件,并采用IR、SEM和化学分析技术对闪爆前后蔗渣纤维的形态、结构、a-纤维素的含量进行了分析,对处理前后的蔗渣纤维的碱化和黄原酸化合成条件进行了优化。结果表明,闪爆预处理技术是一种便宜、迅速、无污染的技术,蔗渣纤维素基黄原酸酯对含金属离子的污水有良好的处理效果。     

用木质纤维素原料生产燃料乙醇预处理工艺研究进展

预处理是利用木质纤维素原料生产燃料乙醇过程中的关键步骤,其直接影响木质纤维素的水解效率和乙醇的生产成本。目前,对木质纤维素原料的预处理方法主要有物理法、化学法、物理化学法和生物法。文章对以上几种预处理方法的研究进行了简要综述,并对各种方法的优缺点进行了分析和讨论,最后对木质纤维素原料生产燃料乙醇预处理方法进行了展望。     

木质纤维“一锅法”制备生物乙醇的研究进展

木质纤维是地球上最丰富的资源,既可以用于制备生物乙醇、生物氢气等生物能源,同时也可以制备各种化工原料及生物基材料,具有绿色、环保、可再生等特点。"一锅法"制备生物乙醇是将预处理、酶解糖化与发酵中的2个或3个连续过程放在同一反应器中进行,具有节约用水、避免物料损失以及在一定程度上提高乙醇产量等优点。通过对预处理与酶解糖化"一锅法",酶解糖化与发酵"一锅法",酶制备、酶解糖化与发酵"一锅法"和预处理、酶解糖化与发酵"一锅法"4类"一锅法"制备生物乙醇方法的介绍,分析了"一锅法"制备生物乙醇的优越性及存在的问题,为使用"一锅法"制备生物乙醇的相关研究提供一定的参考。     

甘蔗渣纤维素的提取及纳米化改性应用研究进展

概述了纤维素的提取方法；综述了甘蔗渣纤维素的预处理方式(物理方法、化学方法、生物法以及混合改性);详细介绍了蔗渣纳米纤维素的制备方法，包括机械法、化学法、微生物法和混合法；对蔗渣纳米纤维素在食品、水处理、医药、复合材料领域的应用进行了总结。     

生物乙醇/丙酮/丁醇生产研究

生物法生产的乙醇、丙酮和丁醇是制药行业重要的溶剂之一,也是可替代生物能源之一。文章对生物发酵法生产乙醇、丙酮和丁醇技术进行了概括,并对其发展的前景进行了展望。     

木质纤维素可再生生物质资源预处理技术的研究进展

阐述了由木质纤维素可再生生物质资源制备生物燃料乙醇对我国可持续发展的重要意义.针对木质纤维素可再生生物质资源利用的关键技术,综述了国内外对木质纤维素可再生生物质资源预处理的研究进展,并重点介绍了物理法、化学法、物理-化学法和生物法预处理木质纤维素可再生生物质资源的技术.最后对木质纤维素可再生生物质资源预处理技术和应用前景进行了展望.     

纤维素燃料乙醇生产技术研究进展

纤维素燃料乙醇已成为下一代燃料乙醇的必然发展方向。文章综述了近年来以木质纤维素为原料生产燃料乙醇的关键技术,重点对物理法、化学法、蒸汽爆破法、生物法等木质纤维素原料预处理技术,酸水解、酶水解等水解(糖化)技术,以及直接发酵法、水解发酵两步法、同步水解发酵法等发酵工艺进行了总结,并指出了未来纤维素乙醇的产业化过程中必须解决的关键问题和发展趋势。     

纤维素乙醇的原料预处理方法及工艺流程研究进展

木质纤维生物质是储量丰富且最有前景的生产燃料乙醇的可再生生物质资源,利用木质纤维生物质生产乙醇主要包括以下步骤：原料预处理、发酵以及产物分离纯化,其中,原料的预处理工艺是限制纤维素乙醇产业化的一个技术瓶颈。本文对酸法、碱法、蒸汽爆破法、合成气法等7种典型预处理方法进行了介绍并对其工艺流程进行简要的说明,同时对不同的预处理方法的优劣、适用范围和工艺流程转化效率等进行了对比,以期为纤维素乙醇预处理方法的工艺选择和评价提供一些参考。提出了纤维素乙醇的产业化前景：不同预处理技术的合理结合使用会有效提高转化率;较好的过程设计能够降低成本,有利于整个过程的经济性。     

生物燃料的技术现状及研究趋势分析

生物液体燃料(燃料乙醇、生物柴油、生物丁醇等)是生物能源战略的重要组成部分,世界范围内产业化运作的液体生物燃料主要包括生物柴油和燃料乙醇。重点对生物柴油和纤维素乙醇这两种生物燃料的技术现状和技术研究趋势进行分析。工业生产生物柴油的主要方法是酯交换法,即利用动植物油脂和低碳醇在催化剂的作用下经酯交换反应生成脂肪酸酯。纤维素乙醇技术目前主要研究集中在开发可高效水解新型木质纤维素原料;开发新型温和预处理工艺;开发新型高效纤维素降解酶系;开发木质素高效利用产品;开发乙醇发酵基因工程菌株这五个方面。还对生物柴油和纤维素乙醇的研究趋势进行了方向性的分析。     

NMMO提取蔗渣纤维素在高取代度羧甲基纤维素钠制备中的应用

对蔗渣进行预处理,利用NMMO(N-甲基吗啉-N-氧化物)对预处理蔗渣进行再生提取,得到纯度较高的再生纤维素。以氯乙酸钠作为醚化剂,在85%乙醇水溶液中,通过二次醚化反应制得了取代度为1.59的羧甲基纤维素钠。利用红外光谱、扫描电镜、X-射线衍射、热重分析等测试手段对制得样品结构进行了表征。     

竹材制取生物乙醇原料预处理技术研究进展

竹子具有可再生性强、生长周期短且富含纤维素、半纤维素,是生产乙醇的重要潜在原料之一。目前有关木质纤维素乙醇的研究主要围绕原料预处理、酶解、发酵三大关键步骤进行,其中原料预处理的能耗和效率问题是该工艺的重要制约因素。本文在综述国内外木质纤维素乙醇原料预处理的基础上,着重分析了竹材的化学组成和结构以及各种竹材预处理的优缺点。包括机械粉碎法能耗大,蒸汽爆破法对设备的要求高,化学方法易造成环境污染,生物方法生产周期长、效率低,离子液体优点明显但需要更深入的研究。提出采用不同预处理工艺联合使用,以期达到优势互补的目的。     

Optimization of Sugarcane Bagasse Hydrolysis by Microwave‐Assisted Pretreatment for Bioethanol Production

Sugarcane bagasse hydrolysis was optimized by dilute‐acid pretreatment and subsequent enzymatic treatment. The studied parameters were microwave heating temperature, residence time, and enzyme dosage as the main factors in a central composite design. The amount of released total reducing sugars, glucose, pentose, phenolic compounds, and furfural were measured after each stage. The optimum conditions with suitable concentrations of inhibitors and reducing sugars were applied for bioethanol production. As an example, ethanol was obtained from reducing sugars by Pichia stipitis without detoxification.     

纤维质原料制乙醇的关键技术

从我国的基本国情出发,提出纤维质原料是我国生产燃料乙醇最可靠的原料。从纤维质原料制燃料乙醇关键技术环节上,分析了原料资源量、原料预处理、高效水解、先进发酵工艺技术的发展趋势和所存在的问题,并在分析各环节存在问题的基础上,对发展纤维质原料的关键技术提出了一些建议。     

高效降解甘蔗渣的预处理技术新进展

甘蔗渣是一种重要的可再生生物质资源,其生物转化利用已成为必然趋势。蔗渣的预处理是利用其生产还原糖的第一个步骤。文章综述了近年来蔗渣预处理技术的新进展,比较了各种预处理技术,并展望其应用前景。     

Integrated design of agricultural and industrial processes: A case study of combined sugar and ethanol production

Bioethanol production from molasses has advantages in greenhouse gas emissions because of its energy acquisition from bagasse. However, the improvement of bioethanol productivity is challenging; while each elemental technology option can be greatly improved, the trade‐offs between the production of raw sugar and bioethanol are complex. This issue should be addressed through the optimization of the whole system, including both agricultural and industrial processes. In this study, we constructed a model of combined raw sugar and bioethanol production from sugarcane considering agricultural and industrial technology options. Data were acquired through a detailed investigation of actual sugar mills. Case studies on the redesign of combined raw sugar and bioethanol production demonstrated that the simultaneous implementation of both technology options increases production of food, materials, and energy from plant‐derived renewable resources, thus demonstrating the effectiveness of the interdisciplinary approach. © 2016 American Institute of Chemical Engineers AIChE J, 63: 560–581, 2017     

Biocatalysts based on immobilized cells of microorganisms in the production of bioethanol and biobutanol

In this work, we discuss the processes for the production of bioethanol and biobutanol, which are promising alternative fuels, using biocatalysts based on cells of various microorganisms immobilized in poly(vinyl alcohol) cryogel. Biocatalysts based on immobilized cells reliably allow ethanol production from a variety of industrial and agricultural wastes (wheat straw, beet and sugarcane bagasse, parchment, corn cobs, soybean processing waste) with a high degree of conversion of consumed substrates to the target product. Ethanol concentrations are appreciably higher in media with biocatalysts than in free cells of the same microorganisms. It is found that immobilized cells of filamentous fungi can convert a wider range of the sugars contained in processed media to ethanol than commonly used yeasts. It is shown that the immobilization of the genus Clostridium cells that produce butanol enables us to reliably change the ratio of solvents that accumulate in the medium during acetone-butanol-ethanol fermentation in the direction of a greater amount of butanol, thereby improving the process’s characteristics relative to present-day technologies based on free bacterial cells.     

Increase in bioethanol production yield from triticale by simultaneous saccharification and fermentation with application of ultrasound

BACKGROUND: Bioethanol produced from renewable biomass, such as sugar, starch or lignocellulosic materials, is one of the alternative energy resources that is environmentally friendly. Triticale crops have a high yield as well as a high starch content and amylolytic enzyme activity and are therefore considered to be ideal for bioethanol production. RESULTS: This study examined the feasibility of ultrasound pretreatment to enhance the release of fermentable sugars from triticale meal during pretreatment and consequently increase bioethanol yield in the simultaneous saccharification and fermentation (SSF) process by Saccharomyces cerevisiae yeast. Ultrasonic pretreatment effectively increased the glucose and maltose content after liquefaction by 15.71% and 52.57%, respectively, compared with the untreated control sample under determined optimal conditions of sonication (5 min, 60 °C). The ultrasound pretreatment consequently improved bioethanol production during SSF processing since the bioethanol content was increased by 10.89%. CONCLUSION: Taking into consideration significant process parameters obtained in the SSF process of triticale meal with ultrasound pretreatment at 60 °C, the process time may be reduced from 72 to 48 h. At that point of the SSF, maximum bioethanol content of 9.55% (w/v), bioethanol yield of 0.43 g g^?1 of triticale starch, and percentage of the theoretical bioethanol yield of 84.56% were achieved. Copyright © 2011 Society of Chemical Industry     

Sustainable management and design of the energy-water-food nexus using a mathematical programming approach

Global primary and secondary resources are important for economic growth. Resource management and environment conservation are currently frequently discussed topics worldwide. In this study, a discrete optimization model formulation is presented for an integrated energy, water, and food (EWF) supply chain problem. The optimization model examines the temporal and spatial integration of the EWF supply chain elements to provide optimal infrastructure capacity expansion of essential commodities within the EWF system, and their corresponding periodic optimal supply for a given region. Furthermore, the model considers endogenous demand between the EWF elements that reflect the interdependency of nexus elements. A mixed integer linear programming model is developed to assist in the process of optimal infrastructure capacity expansion and operation of the EWF system. A case study is given to show the application of the proposed mathematical programming model. Several scenarios are assumed for the case study under different commodity prices and climate change conditions. In addition, diversification in the energy and agriculture sectors is examined by shifting from international refined sugar trading to bioethanol production. The results show economic gains of ~10% under the emergence of bioethanol production compared with the business-as-usual scenario. Production dynamic exits for the production of refined sugar, bioethanol, and power from sugarcane and bagasse resources over time in the considered sale price range for the refined sugar and bioethanol products.