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News and Trendshttp://www.biofuels-news.com/content_item_details.php?item_id=319 The Biofuels International website reports that although their research/analysis points to the use of aviation biofuel blends as the only way to reduce aviation-related GHG emissions, the recent grounding of flights in Europe, due to volcanic ash fallout from Iceland's Eyjafjallajoekull volcano, may have opened "other possibilities". "On a normal day, the 28,000 flights in European airspace emit about 560,000 tonnes of carbon dioxide, or a third of the world's aviation emissions". The grounding of some 63,000 flights in Europe for four days due to the volcanic eruption in Iceland, has reportedly saved "1.3 million tonnes of carbon dioxide, more than the annual emissions of many developing countries".. http://www.biotechnologyforbiofuels.com/content/pdf/1754-6834-3-11.pdf Scientists from the (United States) DOE (Department of Energy) Great Lakes Bioenergy Research Center, Michigan State University, report the side-by-side comparison of cellulose-ethanol fermentation performance of two bacterial strains (Escherichia coli and Zymomonas mobilis), and a yeast strain of Saccharomyces cerevisiae, on a second generation biofuel feedstock. The substrate used was the liquid hydrolyzate from AFEX (ammonia fiber expansion)-pretreated corn stover, supplemented by corn steep liquor (CSL). S. cerevisiae is the commonly used ethanol-fermenting organism in both the beverage and fuel ethanol industries. The bacteria, E. coli and Z. mobilis have recently been considered as potential alternatives to S. cerevisiae, due to their faster growth rates. In contrast to previous comparisons on ethanol fermentation, this study is probably one of the first to compare ethanol fermentation performance of bacteria and yeast, from a second generation biofuel feedstock (i.e. lignocellulosic biomass). Results showed that the three microorganisms were able to ferment the CSL-supplemented AFEX-pretreated corn-stover- hydrolyzate, at a metabolic yield, final concentration, and ethanol productivity of 0.42 g ethanol per g sugar consumed, 40 g ethanol per liter, and 0.7 g ethanol per liter per hour (7 to 48 hours), respectively. The results also showed that glucose fermentations for the three organisms were effective at high solids loading (18% by weight), but xylose consumption in the corn-stover-hydrolyzate is seen as the major bottleneck affecting overall yield and rate of the process. Saccharomyces cerevisiae was gauged as the most "relevant strain for industrial production" for its ability to ferment both glucose and xylose from AFEX-pretreated corn-stover-hydrolyzate. The complete study is published in the open access journal, Biotechnology for Biofuels (URL above). Related information on AFEX (Ammonia Fiber Expansion) Pretreatment http://www.biotechnologyforbiofuels.com/content/3/1/1 Biofuels Processing
The crystallnity index (CI) of cellulose has been commonly used as a parameter to assess/interpret cellulose structures in cellulosic plant biomass, after chemical, biological and/or enzymatic (cellulase) treatments. However, it has been found that the values of crystallinity index vary, depending on the choice of measurement method. With the increasing amount of research devoted to the preatreatment of lignocelluosic biomass for bioenergy production, this may have important implications in the assessment of pretreatment performance. Researchers from the National Renewable Energy Laboratory (NREL, United States) made critical comparisons of four different techniques incorporating X-ray diffraction (XRD) and solid state carbon-13 Nuclear Magnetic Resonance (NMR) methods, on eight different cellulose preparations. Results of the study point to the use of "caution against trying to correlate relatively small changes in the CI with changes in cellulose digestibility". Caution is advised due to the (1) complex nature of cellulase interactions with amorphous and crystalline cellulose, as well as (2) the possibility that factors other than crystallinity (such as lignin/hemicellulose content/distribution, porosity, particle size) may also affect accessibility of cellulose. The complete study is published in the open access journal, Biotechnology for Biofuels (URL above).. Biofuels Policy and Economics
http://www.thebioenergysite.com/news/6257/biofuels-not-harmful-to-food The bioenergy website reports some highlights of the Brazil Biofuels survey made by the Institute of Applied Economic Research (IPEA). The highlights include the following: (1) under an international scenario that the ethanol market will reach 200 billion liters in the next ten years, Brazil exported 4.7 billion liters of ethanol in the last crop year, out of its total production of 25 billion liters, (2) important initiatives must be strengthened as counter measures against protectionist actions based on socio-environmental sustainability; these include, National Commitment for Improving Working Conditions in the Sugarcane Industry, and "the Agro-Ecological Zoning of Sugarcane, which forbids expansion and the setting up of new plants in the Amazon, the Pantanal lowlands and the Alto Paraguai Basin", (3) price stability is one of the main challenges facing the ethanol market, (4) measures to prevent price oscillations include: exemption from tax on ethanol imports, consolidation of a futures market and formation of large stock at the start of the year, (5) the country will not lose its potential as a food producer as a consequence of the expansion of sugarcane crops for biofuel production.. http://www.biofuels-news.com/industry_news.php?item_id=2141 The Biofuels International website reports a joint venture between China and (American aircraft manufacturer) Boeing to develop jatropha-based aviation biofuels, and to launch China's first biofuel-powered flight later this year. The signatories for the joint agreement are the Boeing Company, Air China, and PetroChina; it was signed, following the US-China Strategic and Economic Dialogue meeting. According to Al Bryant (Vice President, Boeing Research and Development Department, China), four biofuel-powered flights have been successfully tested in the United States, and attention has shifted to China due to its desire to "speed up the process". China reportedly contributes about 2% of global gas emissions that are considered harmful. Mr. Bryant says, "We believe that in three to five years we should see a portion of fuel in commercial aviation (using biofuel) but a lot more has to be done; we've proven it can be flown and it is a matter of scaling it up to make it financially viable". "China has now become the top priority for major advancements in the aviation industry"..
http://www.greenfuels.org/files/Doyletech%20Total%20Economic%20Impact%20of%20Biofuels%20Plants.pdf The Biomass Magazine website reports some highlights of the Biofuels Impact Report released by the Canadian Renewable Fuels Association (CRFA), which assesses the economic impacts of renewable investments in Canada. The CFRA commissioned Doyletech (a technology management and research consulting firm) to use its "EconWin model to create total impact assessments for all 28 plants either operating or under construction, taking into account the opportunity costs associated with the construction of a plant". Among the highlights of the study are: (1) the opportunity costs of alternate feedstock sales and renewable energy plants in Canada represent a net economic benefit, which extends from construction phase to current annual operations phase, (2) the major benefits of renewable fuel plants are not merely the provision of transport fuels, but also other benefits, such as the provision of vehicles for rural revitalization and industrial development, (3) all levels of government benefit from renewable fuel plants; "it would seem that incentive programs to encourage biofuels production and use in Canada have been wise investments".. |
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