甜高粱秸秆燃料乙醇产业化问题与对策的探讨

甜高粱具有极高的光合速率,有"高能植物"之称,其单位种植面积的乙醇产量较高.甜高粱特别适合在我国栽培,甜高粱燃料乙醇极具开发价值,它对能源安全和环境保护具有举足轻重的作用.文章简单介绍了新疆甜高粱用于生产低成本燃料乙醇的优势、试验情况以及产业化过程中面临的问题,并提出了解决这些问题应采取的对策.     

甜高粱茎杆制燃料乙醇工程路线探讨

探讨了用甜高粱茎杆工业化生产燃料乙醇的工程路线,分析了工业生产三个明确目标和要求,五个具体矛盾和困难。根据实践采取相应措施,提出了分布式加工体系,循环型经济模式和生物法生产工艺三位一体的完整工程路线。     

甜高粱茎汁酒精发酵研究与应用进展

介绍了甜高粱原料保藏、发酵制取乙醇的高效菌株选育、酵母细胞固定化、发酵条件优化、产业化开发与副产物综合利用等甜高粱茎汁酒精发酵技术的研究与应用进展情况,讨论了原料保藏、良种选育、运行成本等问题是实现甜高粱茎汁酒精发酵大规模工业化生产的关键环节.     

我国非粮作物燃料乙醇技术与产业发展现状

非粮燃料乙醇是我国生物质能源发展的重点之一。本文就我国木薯、甜高粱、菊芋、葛和菊叶薯蓣等几种非粮能源作物的资源优势、非粮乙醇转化技术及其产业发展现状进行探讨,并对我国非粮作物燃料乙醇产业的可持续发展提出了建议。     

甜高粱茎秆制取燃料乙醇产业纵向合作模式调查分析

随着能源问题的日益突出,清洁、可再生的新型能源--燃料乙醇越来越被人们所关注.众多研究表明,甜高粱茎秆是生产燃料乙醇的重要原料.近年来,甜高粱茎秆制取燃料乙醇产业在我国发展迅速,而该产业中纵向合作模式(企业与农户合作模式)是其能否成功发展的重要因素之一.以黑龙江省桦川县甜高梁制乙醇项目为例,在充分细致的调查基础上,对企业与农户的合作模式进行了分析.考虑到企业在合作模式选择上具有绝对的优势地位,以不同模式下企业的成本、收益与风险分析为切人点,研究得出符合企业利益最大化的订单模式,并通过调查农户种植甜高粱的积极性及其影响因素,提出企业实施订单模式的建议.     

中国燃料乙醇的应用及生产技术的效益分析与评价

针对国内外燃料乙醇的应用和发展情况,对比分析了淀粉质、糖质和纤维素类原料燃料乙醇生产工艺的异同,并对我国3种原料的资源状况进行了评价.以10万t/a的燃料乙醇工厂为例,对不同原料燃料乙醇生产工艺的经济性、能源效益和社会效益进行了对比分析,发现甜高梁和木薯最有经济优势;从能源效益分析可知生产工艺能耗约占80%,工艺改进非常重要;从单位土地能源净产出情况看,甜高梁最高,其次是甘蔗和木薯,可见能源作物具有开发潜力;通过社会效益分析,10万t燃料乙醇工厂会给农民带来2～4亿元的年收益,提供约1000个的就业岗位;且10万t燃料乙醇的应用CO2年减排量可达30万t以上,减排CO、CH等汽车有害污染物近1700t.     

燃料乙醇炼制系统优化与碳减排研究进展

生物质是丰富可再生的碳源,以糖、淀粉、秸秆纤维素或其他生物质原料高效生产燃料乙醇,可减少化石能源的需求,其中以木质纤维素为原料的第二代燃料乙醇具有广阔的发展前景。与化石能源相比,燃料乙醇具有环保、经济、可再生的优势,但其在生产工艺技术、经济效益和环境影响等方面仍需要深入研究。近年来,通过开展燃料乙醇炼制系统优化及全生命周期分析研究,有力地促进了燃料乙醇技术进步,推动了燃料乙醇碳减排相关研究。文章主要论述了近年来燃料乙醇生产技术的发展,重点对燃料乙醇系统的模拟优化和碳减排研究进展进行了总结,并对燃料乙醇发展趋势进行了展望,以期为燃料乙醇的可持续发展提供参考。     

菊芋生产燃料乙醇工艺路线探讨

在对菊芋汁清液连续发酵和菊芋粉带渣批式发酵的研究基础上,进行了利用菊芋生产燃料乙醇的两种工艺路线的技术经济可行性分析,提出建立分布式加工体系的策略。菊芋乙醇产业生态系统包括种植、仓储、生产粗乙醇和生产精乙醇4个主生产环节以及副产物综合利用环节。菊芋综合利用路线的提出,期望能够为降低生产成本,实现菊芋原料生产燃料乙醇的产业化提供依据。     

我国生物质燃料乙醇示范工程的全生命周期评价

目前,我国甜高粱、木薯等"非粮"燃料乙醇正处于规模化推广的前期论证阶段,亟需对其进行全面深入的可行性分析.文章基于生命周期评价原理,结合国内4家燃料乙醇生产企业的示范工程,对其全生命周期过程的能源消耗、环境影响和经济成本提供定量的评价结果,为评价、对比"非粮"乙醇和"粮食基"乙醇提供科学、权威的数据,填补了这一方面国内研究领域的空白.评价结果表明,发展甜高粱和木薯等非粮乙醇是可行的,与玉米乙醇相比具有较强的优势.     

我国燃料乙醇发展现状和趋势分析

原油价格高企和日益严重的环境污染问题,使得人们越来越关注燃料乙醇等清洁环保的可再生能源。我国2001年开始发展燃料乙醇,已成为第三大燃料乙醇生产国,但我国目前以玉米和小麦等粮食为原料生产燃料乙醇,成本较高且影响国家粮食安全。本文从产业政策和经济效益角度分析了我国燃料乙醇发展趋势和原料路线选择,燃料乙醇的发展应立足于中国国情,走以非粮作物如木薯和纤维素为原料的生产路线。以木薯为原料生产燃料乙醇,技术成熟,经济效益良好。以纤维素为原料生产燃料乙醇,具有广阔的发展前景,是未来燃料乙醇的发展趋势,但目前技术不成熟,生产燃料乙醇成本较高。     

Economic feasibility of producing sweet sorghum as an ethanol feedstock in the southeastern United States

This study examines the feasibility of producing sweet sorghum (Sorghum bicolor (L.) Moench) as an ethanol feedstock in the southeastern United States through representative counties in Mississippi. We construct enterprise budgets along with estimates of transportation costs to estimate sweet sorghum producers’ breakeven costs for producing and delivering sweet sorghum biomass. This breakeven cost for the sweet sorghum producer is used to estimate breakeven costs for the ethanol producer based on wholesale ethanol price, production costs, and transportation and marketing costs. Stochastic models are developed to estimate profits for sweet sorghum and competing crops in two representative counties in Mississippi, with sweet sorghum consistently yielding losses in both counties.     

我国非粮燃料乙醇的原料资源量分析

目前世界燃料乙醇的生产原料约60%为甘蔗或甜菜等糖质原料、33%为玉米或小麦等淀粉质原料,而纤维质原料正日益受到重视。我国可用于生产燃料乙醇的非粮淀粉质原料主要有甘薯、木薯、蕉藕、葛根等。其中蕉藕目前尚未形成产业化生产;葛根原料价格高,不宜作为乙醇原料;甘薯归属粮食范畴;只有木薯是最适宜制燃料乙醇的非粮淀粉质原料。纤维质原料主要包括农作物秸秆、农林废弃物、木屑等,其中农作物秸秆是我国产量最大的非粮燃料乙醇原料。秸秆资源密度考虑,利用区域应主要集中在河南、山东、江苏等地,保守估计这3个省的秸秆量可供生产1117×104t乙醇。目前制约纤维质原料制乙醇的关键瓶颈之一是原料的收集、运输及供应保障,若没有国家大的政策扶持和资金补贴,纤维质原料因缺乏经济可行性而尚不具备工业化生产乙醇的条件。糖质原料主要有甘蔗、甜菜、甜高粱茎秆和菊芋。由于菊芋菊粉附加值高,不宜作乙醇原料;甘蔗、甜菜主要用于糖业,不会作为乙醇原料;从单位土地面积乙醇产量和原料成本、农民种植收益综合来看,甜高粱茎秆是适宜生产燃料乙醇的糖质原料。需要寻求产业化种植模式来落实资源总量,提高资源保障度;另一方面要进一步研究低成本、安全保质的茎秆储藏技术。     

Techno-economic analysis of integrating sweet sorghum into sugar mills: The Central American case

This paper aims to evaluate the potential for electricity and ethanol production in Central America using sweet sorghum, performing a techno-economic analysis. The study proposes the integration of sweet sorghum into Central American sugar mills, by using the existing machinery to process this crop during off-season. A process simulation and a cost model were developed to estimate the technical and economical feasibility of sweet sorghum integration. The data on various parameters used for techno-economic assessment were collected from an existing sugar mill and distillery in Central America. The results show that a sugar mill operating 2 months during off-season could obtain an average revenue of US$ 3 M for a crushing rate of 6500 t/d. Ethanol production costs are estimated to be 24.76 ¢US$/L. In case a new CHP plant is built, a sugar mill operating under the integrated scenario would have a payback period of 4.49 years, as compared to 7.47 years for a sugar mill using sugarcane bagasse as the only fuel. Although several studies highlight the potential of sweet sorghum for ethanol production, the results from this work prove that sweet sorghum must also be seen as a viable feedstock for electricity production. A sensitivity analysis was also performed to determine the variation of the average cost of electricity and ethanol with the variables used in the economic analysis. For all analysed scenarios the effects of installed capacity and crop yield prevailed over the increasing costs of land and transportation.     

能源作物甜高粱及其可供应性研究

甜高粱是一种具有优良特性的能源作物，在我国利用甜高粱生产燃料酒精有着广阔的发展前景。文章在详细介绍了甜高粱生物学特性的基础上，对我国甜高粱新品种的研究和开发现状进行了汇总分析，对今后我国发展能源作物甜高粱的土地可供应性和生产燃料酒精的潜力进行了深入研究。     

Sugar-ethanol-electricity co-generation in Hawai’i: An application of linear programming (LP) for optimizing strategies

This research develops a linear programming (LP) model to assess various options for sugar and biofuel production from sugarcane and other feedstock in Hawaii. More specifically, the study focuses on finding optimal sugar and biomass feedstock that would maximize producer profits in the production of sugar, ethanol and electricity. Feedstock included in the model were sugarcane, banagrass, energy cane and sweet sorghum. Given available land resources for growing energy crops on the island of Maui, four land resource scenarios were considered. If available land resources were used in the production of sugarcane and energy crops with added utilization of non-prime lands, Hawaii's ethanol goal for year 2020 could be achieved while maintaining two-thirds of Hawaii's current sugar production. Crop yields and unit production costs are key factors in determining optimal quantities of feedstock in the optimization model tested in this study.     

油污地甜高粱茎秆汁液制取酒精的试验研究

采用正交试验的方法,以辽宁沈抚污灌区栽种的甜高粱茎秆为试材,研究了氮、钾、镁营养盐填加量对酒精产率的影响,确定了甜高梁发酵酒精的适宜工艺。结果表明,在油污地栽种的甜高粱可用来发酵生产酒精;在发酵液中添加0．5％的磷酸二氧钾,0．05％的硫酸铵,0．05％的硫酸镁,5-6h后可得到较高的酒精产率（可达理论产率的93％）。     

Quest for sustainable bio‐production and recovery of butanol as a promising solution to fossil fuel

Biobutanol has conventionally been generated by fermentation of carbohydrates derived from biomass (starch or sugar‐based feedstock, such as corn) using Clostridia strains (mainly C. beijerinckii and C. acetobutylicum) under anaerobic conditions in batch mode. Under these premises, it has been tough for the acetone–butanol–ethanol fermentation to compete with petro‐butanol production from an energy efficiency and material consumption standpoint. Challenges for butanol production from biomass comprised high cost of feedstock, scarcity of hyper‐butanol producing bacteria and low butanol yield, volumetric productivity and titre, leading to high water usage and separation‐purification costs. This article is an up‐to‐date review on several under explored sections, such as optimization of fermenter feed, microbial culture responsible for solvent production (co‐culture techniques and electro‐biochemical process), latest recovery techniques and the studies integrating in situ continuous fermentation processes. Biobutanol refinery way forward should build upon the use of low‐cost lignocellulosic matter and zero cost organic wastes and by‐products from food, agriculture, forestry, fermentation and paper industries as feedstock; optimized fermentation of such diversified feed with appropriate hyper‐butanol producing strains in biofilm reactors and integration of fermentation step with hybrid high butanol‐selective recovery techniques. Copyright © 2015 John Wiley & Sons, Ltd.     

Modeling of rotating drum bioreactor for anaerobic solid-state fermentation

Solid-state fermentation (SSF) has received more attention and has been applied to production of different products in recent years, especially biofuel production. The major problems to overcome in large-scale SSF are heat accumulation and heterogeneous distribution in a complex gas–liquid–solid multiphase bioreactor (or fermenter) system. In this work, a mathematical model of a rotating drum bioreactor for anaerobic SSF is developed considering the radial temperature distribution in the substrate bed. Validation experiments were conducted in a 5 m³ pilot plant fermenter for production of fuel ethanol from milled sweet sorghum stalks. The model that was developed fit well with the experimental data. From these results, it was concluded that this mathematical model is a powerful tool to investigate the design and scale-up of an anaerobic SSF fermenter in the application of bioethanol production using cellulosic materials such as sweet sorghum stalks.     

Study on genotypic variation for ethanol production from sweet sorghum juice

Sugarcane molasses is the main source for ethanol production in India. Sweet sorghum with its juicy stem containing sugars equivalent to that of sugarcane is a very good alternative for bio-ethanol production to meet the energy needs of the country. Sweet sorghum is drought resistant, water logging resistant and saline–alkaline tolerant. Growing sweet sorghum for ethanol production is relatively easy and economical and ethanol produced from sweet sorghum is eco-friendly. In view of this, it is important to identify superior genotypes for ethanol production in terms of percent juice brix, juice extractability, total fermentable sugars, ethanol yield and fermentation efficiency. This paper presents the study on the variability observed for the production of ethanol by various sweet sorghum genotypes in a laboratory fermentor. Five Sweet Sorghum (Sorghum bicolor L. Moench) genotypes were evaluated for ethanol production from stalk juice (Keller, SSV 84, Wray, NSSH 104 and BJ 248). Sweet sorghum juice differs from cane juice mainly in its higher content of starch and aconitic acid. Data were collected for biomass yield; stalk sugar yield and ethanol production in five genotypes. Maximum ethanol production of 9.0%w/v ethanol was obtained with Keller variety (20% sugar concentration was used), and decreased for other genotypes. A distiller's strain of Saccharomyces cerevisiae (gifted by Seagram Distilleries Ltd.) was employed for fermentation. The fermentation efficiency (FE) was 94.7% for this strain. High biomass of yeast was obtained with BJ 248 variety. When the similar experiments were conducted with unsterile sweet sorghum juice (15% sugar concentration) 6.47%w/v ethanol was produced.