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Biofuel Industry (biofuel + industry)
Selected AbstractsEnzymatic deconstruction of xylan for biofuel productionGCB BIOENERGY, Issue 1 2009DYLAN DODD Abstract The combustion of fossil-derived fuels has a significant impact on atmospheric carbon dioxide (CO2) levels and correspondingly is an important contributor to anthropogenic global climate change. Plants have evolved photosynthetic mechanisms in which solar energy is used to fix CO2 into carbohydrates. Thus, combustion of biofuels, derived from plant biomass, can be considered a potentially carbon neutral process. One of the major limitations for efficient conversion of plant biomass to biofuels is the recalcitrant nature of the plant cell wall, which is composed mostly of lignocellulosic materials (lignin, cellulose, and hemicellulose). The heteropolymer xylan represents the most abundant hemicellulosic polysaccharide and is composed primarily of xylose, arabinose, and glucuronic acid. Microbes have evolved a plethora of enzymatic strategies for hydrolyzing xylan into its constituent sugars for subsequent fermentation to biofuels. Therefore, microorganisms are considered an important source of biocatalysts in the emerging biofuel industry. To produce an optimized enzymatic cocktail for xylan deconstruction, it will be valuable to gain insight at the molecular level of the chemical linkages and the mechanisms by which these enzymes recognize their substrates and catalyze their reactions. Recent advances in genomics, proteomics, and structural biology have revolutionized our understanding of the microbial xylanolytic enzymes. This review focuses on current understanding of the molecular basis for substrate specificity and catalysis by enzymes involved in xylan deconstruction. [source] Experimental validation of CFD simulations of a lab-scale fluidized-bed reactor with and without side-gas injectionAICHE JOURNAL, Issue 6 2010Jian Min Abstract Fluidized-bed reactors are widely used in the biofuel industry for combustion, pyrolysis, and gasification processes. In this work, a lab-scale fluidized-bed reactor without and with side-gas injection and filled with 500,600 ,m glass beads is simulated using the computational fluid dynamics (CFD) code Fluent 6.3, and the results are compared to experimental data obtained using pressure measurements and 3D X-ray computed tomography. An initial grid-dependence CFD study is carried out using 2D simulations, and it is shown that a 4-mm grid resolution is sufficient to capture the time- and spatial-averaged local gas holdup in the lab-scale reactor. Full 3D simulations are then compared with the experimental data on 2D vertical slices through the fluidized bed. Both the experiments and CFD simulations without side-gas injection show that in the cross section of the fluidized bed there are two large off-center symmetric regions in which the gas holdup is larger than in the center of the fluidized bed. The 3D simulations using the Syamlal-O'Brien and Gidaspow drag models predict well the local gas holdup variation throughout the entire fluidized bed when compared to the experimental data. In comparison, simulations with the Wen-Yu drag model generally over predict the local gas holdup. The agreement between experiments and simulations with side-gas injection is generally good, where the side-gas injection simulates the immediate volatilization of biomass. However, the effect of the side-gas injection extends further into the fluidized bed in the experiments as compared to the simulations. Overall the simulations under predict the gas dispersion rate above the side-gas injector. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] The use of multiple correspondence analysis and hierarchical clustering to identify incident typologies pertaining to the biofuel industryBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 1 2010Carine Riviére Abstract Biofuel production has been expanding for more than five years, leading to an increasing number of production sites worldwide and also to a tremendous diversification of processes and approaches to producing biofuel. Such a fast move in industry has sometimes proven in the past to potentially lead to underestimating safety management needs. The significant number of existing facilities producing so called first generation biofuel allows for a reasonable survey of safety issues from incidents. In 2006, INERIS initiated research work devoted to the analysis of safety-related issues including the implementation of an incidents database. Its purpose is to collect known and reasonably well documented incidents (explosions, fires, spills, derailments, and road accidents) that relate to the life cycle of biofuel supply chains. This paper focuses on the analysis of this database, which contains 100 incidents that occurred from January 2000 to early 2009. From the database, an attempt has been made to identify the root factors of incidents potentially impacting biofuel supply chains, using statistical methods like multiple correspondence analysis and ascendant hierarchical clustering. This multivariate analysis exercise has led us to identify five main incident typologies, which in turn allows us to draw appropriate information on safety issues pertaining to first-generation biofuel supply chains. Each typology is illustrated by actual cases of accidents. Copyright © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Catastrophic incident prevention and proactive risk management in the new biofuels industry,ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2009Judy A. Perry Abstract This article is directed at assisting bioethanol manufacturers with preventing catastrophic incidents which could impact the entire Biofuels Industry. The biofuels industry has common hazards and potential consequences like other industries, related to the handling of flammables, dust explosion hazards and toxic or corrosive materials handling. This article ensures the reader understands these specific bioethanol manufacturer's process hazards are very real as demonstrated by past incidents and their catastrophic results. Regulatory obligations are discussed, as well as key engineering resources and design practices to ensure adequate safeguards are incorporated into the design of a new bioethanol manufacturing facility. The industry is fairly new, however, the hazards and safeguards to reduce the risk level with the common hazards are not new. Preliminary indications are this industry has yet to establish the proactive risk management efforts that are required to reduce the risks to a tolerable level. This article is to provide the supporting data and direction to the Biofuels Industry to ensure each are headed down a path of preventing a future catastrophe. © 2009 American Institute of Chemical Engineers Environ Prog, 2009 [source] Interest of industrial actors in biorefinery concepts in EuropeBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 3 2009Klaus Menrad Abstract To satisfy the rising demand for agricultural and forestry products it is becoming more and more important to use biomass as efficiently as possible. One way of achieving that goal is to implement biorefinery systems in which biomass can be utilized entirely by conversion through multiple processes into a number of valuable products. To pursue the implementation of biorefinery systems, it is important to know to what extent the industry is interested in such concepts. This perspective deals with the results of a cross-European survey investigating the interests of potential industrial actors in biorefinery concepts. A high resonance was identified amongst companies belonging to the biofuels industry; companies active in this sector, therefore, could possibly provide access to further integrated concepts. On the whole, the results reflect a very positive attitude toward biorefinery concepts. But there are also problems with respect to the political and legal framework; policy and legislation may be required to establish stable framework conditions and provide planning security for investment decisions. Oilseed and lignocellulosic feedstock is primarily utilized within the surveyed companies; fuel, heat and power are the primary products produced from biomass. Additionally, the survey showed that biorefinery concepts are highly influenced by aspects concerning regional value chains. On the upstream side ,feedstock issues' appear to be especially important for biorefineries. In general, sustainability aspects are considered to be a benefit of biorefinery concepts. This suggests opportunities for the design of marketing and communication strategies based on ecological aspects of biorefinery implementation. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] The development of biocommodities and the role of North West European ports in biomass chainsBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 3 2009Johan P. M. Sanders Abstract Biomass-derived commodities will compete with commodities derived from fossil fuels in 20 years' time. This perspective will explore the economic conditions that will govern the development of, and the trade in these biocommodities. Markets for biocommodities will open up new revenues for both the agricultural and the chemical sector. We shall explore the importance of the biorefinery concept for the establishment of these new markets. Biorefinery is the sustainable processing of biomass into a spectrum of marketable products and energy. Trade in biobased substances will be greatly enhance if standard ,commodities' are defined and produced in several places in the world. Now we turn to the second question of this perspective: where will biocommodities be produced and where will they be used? The choice of where to process the biomass will depend on the type of biomass, transport distances, bulk density, decay rate, ease of handling, the type of process(ses), the presence of markets, the cost of labor, and logistical conditions. Ports, both on the exporting side and on the importing side, will have a major influence on the formation of biomass chains. In export ports, crude or partially pre-treated biomass will be collected and processed/ transformed into a biocommodity. Existing industries, such as feed production, can be combined with the production of biocommodities, The role of port areas and chemical industries in several biomass chains are shown. The combination of a major port and major application markets for biomass, such as feed industry, chemical industry, biofuels industry and power generation, will allow for the formation of a biomass hub. The formation of a biomass hub will be a step-by-step process in which services and exchange markets are added to existing logistical and industrial structures. The port of Rotterdam has an excellent starting point to become a hub in international biomass trade and processing. In the near future, 5,15 years from now, international biomass trade will become standardized and biocommodities will be defined, partly on the basis of technologies still in development. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] | ||||||||||