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Jatropha Curcase in Oahu and Mozambique : Acknowledging scientific differences and resulting questionsMarshall, Lindsey January 2010 (has links)
In the current search for alternatives to fossil energy sources, scientists have expanded their biofuel research pools to include non-traditional crops. Plants that were once only thought of as food crops (for example rapeseed, maize, sugarcane, and sugar beet) are now experimented with and used for biofuel supply. Other plants that did not have any agricultural or commercial use are now integral parts of biofuel research and advancement. One of these plants, Jatropha curcas, has spread through the biofuel communities throughout the world. Jatropha curcas is noted for its high quality oil and ability to grow in poor conditions. Most of the interest in this tree is concentrated in the tropics, where a year-round growing/harvest season is possible. This study was conducted in order to view and discuss Jatropha curcas in two different settings: two test fields at the Hawaiian Agricultural Research Centers on Oahu, Hawaii, and Sun Biofuels plantation in Chimoio, Mozambique. After visiting Oahu, it was clear that, although some significant steps in pruning techniques had been achieved, many of the questions surrounding jatropha remained unanswered. These questions included, but were not limited to: What is the ideal irrigation level? Is the plant close to domestication? How can optimal yield be achieved? Are there ways to avoid dormancy? Additionally, as a result of the research, many new questions regarding environmental, social, agricultural, and economic aspects of jatropha arose. In Chimoio, it became immediately apparent that the plantation was little more than a huge test plot at its current stage in August, 2009. There was no infrastructure being set-up or built either at Sun Biofuels or in the surrounding cities to accommodate for machine harvesting, crushing, pressing, storage, and transportation, even though the first harvest was scheduled for 2010. Additionally, there were no on-site engineers or scientists to help with the initial phases of growth and harvest. It was evident that jatropha was growing on good quality soil in both Hawaii and Mozambique, and jatropha crops were planted on previous agricultural land. Just because it was shown that jatropha could grow on poor quality land does not mean that it actually grows there in a plantation-like environment. Additionally, because it was been proven that jatropha can grow on good quality soil does not mean it is a competitive substitute for other biofuel crops. It is clear that jatropha has highly irregular qualities (for example, growth, seed content, oil content, oil properties) not just in different parts of the world or even in different plantations, but from genetically identical trees in the same plantation with the same growing conditions. This is an explanation for why jatropha data is so inconsistent across the world. Further scientific and engineering research must be put into jatropha before a company should embark on a large-scale plantation venture. / I dagens sökande efter alternativ till fossila energikällor har forskningen inom biobränsleområdet kommit att inkludera icke-traditionella grödor. Växter som tidigare bara var tänkta som livsmedelsgrödor (t.ex. raps, majs, sockerrör och sockerbetor) ingår idag i experiment och används inom biobränsleutbudet. Andra växter som tidigare inte haft något kommersiellt användningsområde är idag en integrerad del av biobränsleforskningen. En av dessa växter, trädet Jatropha curcas, har spridit sig inom biobränslesamhällen över hela världen. Jatropha är känd för sin högkvalitativa olja och sin förmåga att växa under förhållanden som skulle vara dåliga för andra grödor. Intresset för jatropha är koncentrerat till tropikerna, där skördesäsongen sträcker sig över hela året. Denna studie genomfördes för att undersöka och diskutera Jatropha curcas i två olika miljöer: på The Hawaiian Agricultural Research Center, Oahu, Hawaii samt på Sun Biofuels Plantation, Chimoio, Mozambique. Efter att ha besökt Oahu var det tydligt att även om vissa betydelsefulla framsteg inom beskärningsteknik hade uppnåtts, så är fortfarande många av frågorna kring jatropha obesvarade. Dessa frågor inkluderar, men är inte begränsade till: Vilken är den ideala bevattningsnivån? Kan växten domesticeras? Hur kan optimal avkastning uppnås? Finns det något sätt att undvika trädets naturliga viloperioder? Dessutom, som ett resultat av forskningen, har många nya frågor dykt upp, rörande miljömässiga, sociala, ekonomiska och jordbruksrelaterade effekter av jatrophaodling. I Chimoio blev det uppenbart att Sun Biofuels jatrophaodling, i augusti 2009, inte var mycket mer än en stor försöksanläggning. Ingen infrastruktur vid anläggningen eller i kringliggande städer var inrättad för att möjliggöra maskinell skördning, krossning, pressning, lagring och transportering – trots att första skörden var planerad redan till 2010. Dessutom fanns inga ingenjörer eller forskare på plats för att vara behjälpliga med de inledande faserna av tillväxt och skörd. Relevant data som har samlats in från de två besökta områdena, samt undersökt litteratur, presenteras i resultaten. Det är tydligt att jatropha har mycket varierande egenskaper med avseende på till exempel tillväxt, frönsättning, oljehalt samt oljans egenskaper; inte bara mellan olika delar av världen eller ens mellan olika planteringar, utan också från genetiskt identiska träd i samma plantering med samma odlingsförhållanden. Detta är en förklaring till varför data om jatropha från studier över hela världen är så inkonsekventa. De frågor som uppkom från både Oahu och Chimoio tas upp i diskussionen. Det är uppenbart att ytterligare vetenskaplig och teknisk forskning måste investeras i jatropha innan ett företag kan tänkas ta sig an en storskalig produktion. Det är uppenbart att de två undersökta plantagerna saknar såväl god vetenskaplig kunskap om jatropha som utrustning för dess hantering.
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Sustainable Production of Fuel : A Study for Customer Adoption of 2nd Generation of BiofuelJin, Ying January 2010 (has links)
Abstract Finding a new fuel to substitute gasoline which reducing rapidly every year, is an urgent problem in the world. In this situation, biofuel is considered to be one kind of new fuel which make no pollution. Nowadays, 1st generation biofuel is familiar with people and adopted by customers, which make it have a stable market share. Since it also brings new problems, 2nd generation biofuel appear and solve all the problems.In the thesis, I compared the pros and cons between the 1st and 2nd generation biofuel in order to find the possibility if the 2nd generation biofuel can substitute the 1st generation biofuel in the petroleum market. And the customer surveys will also show the detail ideas and data about the customers’ options. If people trust the 2nd generation biofuel can substitute the 1st generation one, the new biofuel will have the stable market share in the future . It means 2nd generation biofuel could be easily introduced in the market.This thesis investigate the possibility for introducing 2nd generation biofuels into the petroleum market. The theories based on the market segments, customer buying behavior, customer value, adopt decision making and characteristic of innovations.This study contain data which includes five interviews and one hundred customer surveys. It shows consumers’ personal idea and some managers’ thinking about whether 2nd generation biofuels will be potential in the market.In the thesis, it will indicate whether customers will be easily or difficult to adopt the new product and find the critical issues for the adoption.
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Process Design and Optimization of Biorefining PathwaysBao, Buping 2012 May 1900 (has links)
Synthesis and screening of technology alternatives is a key process-development activity in the process industries. Recently, this has become particularly important for the conceptual design of biorefineries. A structural representation (referred to as the chemical species/conversion operator) is introduced. It is used to track individual chemicals while allowing for the processing of multiple chemicals in processing technologies. The representation is used to embed potential configurations of interest. An optimization approach is developed to screen and determine optimum network configurations for various technology pathways using simple data.
The design of separation systems is an essential component in the design of biorefineries and hydrocarbon processing facilities. This work introduces methodical techniques for the synthesis and selection of separation networks. A shortcut method is developed for the separation of intermediates and products in biorefineries. The optimal allocation of conversion technologies and recycle design is determined in conjunction with the selection of the separation systems. The work also investigates the selection of separation systems for gas-to-liquid (GTL) technologies using supercritical Fischer-Tropsch synthesis. The task of the separation network is to exploit the pressure profile of the process, the availability of the solvent as a process product, and the techno-economic advantages of recovering and recycling the solvent. Case studies are solved to illustrate the effectiveness of the various techniques developed in this work.
The result shows 1, the optimal pathway based on minimum payback period for cost efficiency is pathway through alcohol fermentation and oligomerized to gasoline as 11.7 years with 1620 tonne/day of feedstock. When the capacity is increased to 120,000 BPD of gasoline production, the payback period will be reduced to 3.4 years. 2, from the proposed separation configuration, the solvent is recovered 99% from the FT products, while not affecting the heavier components recovery and light gas recovery, and 99% of waster is recycled. The SCF-FT case is competitive with the traditional FT case with similar ROI 0.2. 3, The proposed process has comparable major parts cost with typical GTL process and the capital investment per BPD is within the range of existing GTL plant.
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Comparison of Biological and Thermal (Pyrolysis) Pathways for Conversion of Lignocellulose to BiofuelsImam, Tahmina 1983- 14 March 2013 (has links)
Because of the limited supply of imported crude oil and environmental degradation, renewable energy is becoming commercially feasible and environmentally desirable. In this research, biological and thermal (pyrolysis) conversion pathways for biofuel production from lignocellulosic feedstocks were compared. For biological conversions of sorghum, ethanol yield was improved using M81-E variety (0.072 g/g juice) over Umbrella (0.065 g/g juice) for first-generation biomass (sorghum juice), and 0.042 g/g sorghum was obtained from the cellulosic portion of second-generation biomass. When ultrasonication was combined with hot water pretreatment, yields increased by 15% and 7% for cellulose to glucose, and hemicellulose to pentose, respectively. Ethanol yield was 10% higher when this pretreatment was combined with Accellerase 1500+XC for saccharification. Biological conversion yielded 1,600?2,300 L ethanol/ha for first-generation biomass, and 4,300?4,500 L ethanol/ha from lignocellulosic biomass.
For thermal (pyrolysis) conversion of lignocellulosic switchgrass at 600 degrees C, product yield was 37% bio-oil, 26% syngas, and 25% bio-char. At 400 degrees C, product yield was 22% bio-oil, 8% syngas, and 56% bio-char. Bio-oil from pyrolysis was highly oxygenated (37 wt%). It required chemical transformation to increase its volatility and thermal stability, and to reduce its viscosity by removing objectionable oxygen, so the product could be used as transportation fuel (gasoline). As a consequence of upgrading bio-oil by catalytic hydrogenation, bio-oil oxygen decreased from 37?2 wt%, carbon increased from 50?83 wt%, hydrogen increased from 9?15 wt% and heating value increased from 36?46 MJ/kg, resulting in a fuel that was comparable to gasoline. The upgraded product passed the thermal stability test when kept under an oxygen-rich environment. The upgraded product consisted of 14.8% parrafins, 21.7% iso-parrafins, 3% napthene, 42.6% aromatics, 4.7% olefin, 4.7% DMF, 8% alcohol, and 0.6% ketone on a mass basis.
Comparing the two pathways, biological conversion had 11 wt% ethanol yield from sorghum, and thermal conversion had 13 wt% gasoline yield from switchgrass. For process efficiency, thermal conversion had 35% energy loss versus 45% energy loss for biological conversions. For the biological pathway, ethanol cost was $2.5/gallon ($4/gallon, gasoline equivalent), whereas for the thermal pathway, switchgrass gasoline cost was $3.7/gallon, both with 15% before tax profit.
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Electrolytic Methods as a Cost and Energy Effective Alternative of Harvesting Algae for BiofuelMorrison, Taylor 1986- 14 March 2013 (has links)
Process variables of electrolytic technology to reduce the energy consumption of harvesting Nonnocloropsis salina were investigated including electro-coagulation, electro-floatation, and electro-flocculation. Electro-coagulation and electro-flocculation showed significant cost savings, however electro-floatation did not. The objectives were to determine the effects of electrode material, pH adjustment and electro-polymer addition for electro-coagulation and determine the performance characteristics for electro-coagulation and electro-flocculation. Both treatments proved to be competitive with the energy consumption of a centrifuge. The best electrolytic treatments were electro-coagulation with aluminum and nickel electrodes. Energy requirements at optimum conditions were 239 and 344 kWh/ton. The best treatment combination using electro-flocculation was 432 kWh/ton with no electrode consumption, which could lead to potential cost savings.
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Phytoremediation of Heavy Oil Contaminated Soils through Biofuel and Energy CropsChang, Ya-chu 11 July 2008 (has links)
In this study, we used biofuel crops to treat the soils contaminated by heavy oil by using phytoremediation biotechniques. The experiments of this study were divided into tree stages. In the first stage, we simulated real situation, and planted biofuel crops ( soybeans, the sunflower),while the mycorrhizal fungi of Gloums mosseae inoculated the plants in the soils contaminated by oil pollution of fuel (10,000 ppm) artificially. In the soils, the plants were cultivated in pots of 63 days through the experiment. The experiment results revealed that the removal rate of oil was 70%. In the second stage, fuel oil was degraded and tested for the plants of biofuel crops ( soybeans, the sunflower). The specics of Gloums mixed with other species of mycorrhizal fungi were used in the soils contaminated by fuel (5000 ppm) artificially. In the soils, plants were cultivated in a pot of 30 days through the experiment. The experiment result revealed that the fuel oil removal rate was 60% in soils. In the third stage, the seed greasy dirt tolerance experiment were run for the biofuel crops ( soybeans, the sunflower, rape, maize).The fuel oil with three different concentrations (5000 ppm, 10,000 ppm, 30,000 ppm)were used in the polluted soils cultivated in a pot for 30 days through the experiment. The experimental result reveals, that sunflower and maize were found less apt to receive the inhibition of the fuel oil. During the first stage and second stage, the plant species of soybeans inoculated by mycorrhizal fungi, soybean presented significant phytostabilization and rhizodegradation, while the plant species of sunflower inoculated by mycorrhizal fungi also exhibited significant phytoextraction and rhizodegradation. In the future, they can match the other biofuel crops inoculated by different mycorrhizal fungi, which will increase the ability to remove fuel oil in the soil.
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Characterization of Arabidopsis Glycoside Hydrolases Family 9 GenesLi, Ya-ru 26 January 2010 (has links)
Generation of alcohol for biofuels from fermentation of sugar or starch has several economic disadvantages such as high cost of sugar processing and land usage competing with staple food. The solution may reside in hydrolysis of cellulose from crop waste such as stalks of rice and corn or non-crop plants such as weeds or wood. Our goal is to identify cellulases that can degrade cellulosic biomass more efficiently. Studies of microbial Family 9 glycoside hydrolase (GH9) proteins, including both endo-glucanases (EC 3.2.1.4) and cellobiohydrolases (EC 3.2.1.91), have shown that they function through an inverting mechanism to cleave the 1, 4-£]-glucosidic bond between two unsubstituted Glc units. The main function of plant glycoside hydrolases are involved in polysaccharide metabolism of cell wall during cell growth. Twelve Arabidopsis thaliana (Columbia) endo-1,4-£]-glucanases that belong to the GH9, were cloned and expressed in Pichia pastoris in order to produce cellulases to facilitate efficient bio-alcohol production. The recombinant proteins do not show in vitro endo-1, 4-£]-glucanase activity, but we can detect the recombinant proteins expression in supernatant or in pellet. The lack of enzymatic activity from recombinant proteins is probably due to improper folding or glycosylation, or fast degradation resulted from the above reasons. Other bioreactor will be tested in the future. Genetic engineering to modify Arabidopsis thaliana (Columbia) endo-£]-1, 4-glucanases is another approach to produce functional cellulases with economic efficiency that can be adapted to industrial scale for alcohol generation. On the other hand, we use semi-quantitative PCR method to study the Arabidopsis GH9 genes expression level in different tissue. At4g39000 and At3g43860 were found only in flowers and inflorescence, and At1g65610 expression in roots and shoots of the amount of more. Other genes in different tissues, was no found significant difference.
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Thin film nanoporous silica and graphene based biofuel cells (iBFCs) for low-power implantable medical device applicationsSharma, Tushar 23 February 2011 (has links)
This thesis describes the fabrication and characterization of an inorganic catalyst based glucose Biofuel cell using nanoporous (mesoporous) silica thin-film as a functional membrane. The desired use of nanoporous silica based biofuel cell is for a blood vessel implantable device. Blood vessel implantable Biofuel Cells (iBFCs) are subjected to higher glucose concentrations and blood flow rates. However, reduction in the implant thickness is critical for the intra-vascular implantable Biofuel cells. Platinum thin-film (thickness: 25 nm) deposited on Silicon substrate (500 [mu]m) served as the anode while Graphene pressed on Stainless steel mesh (175 [mu]m) was used as the cathode. Control experiments involved the use of surfactant-coated polypropylene membrane (50 [mu]m) and Activated Carbon (198 [mu]m) electrodes. Preliminary results show that nanoporous silica thin film (270 nm) is capable of replacing the conventional polymer based membranes with an increased power density output of as high as 10 [mu]W/cm2 under physiological conditions. in-vitro (5 [mu]W/cm2) and in-vivo (10 [mu]W/cm2) experiments demonstrate the potential of ultra-thin iBFCs towards powering future medical implants. / text
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Microalgae as the Third Generation Biofuel:Production, Usage, Challenges and ProspectsWang, Yue January 2013 (has links)
Microalgae refer to a kind of autotrophic microorganism with rich nutrition and high photosynthetic utilization degree, which are widely living in the sea and land. Microalgae can be converted into bio energy such as biogas, biodiesel and bio oil. This thesis presents a review on the different cultivation methods and energy conversion techniques of microalgae. Through comparison with other biomass feedstocks, the advantages and disadvantages of microalgae are detailed. Since the large scale of microalgae bioenergy production has not been achieved yet, the commercial production requirements and the sustainability of microalgae are analysed. As a result, high lipid content, less cultivated land use and short life time circle are thought to be the typical advantages of microalgae that it can be considered as a potential substitute of fossil fuel.
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Atomic Force Microscopy Study of Endoglucanases and Cellobiohydrolases on Native Cellulose FilmsQuirk, Amanda 20 March 2012 (has links)
Atomic force microscopy was used to image the action of cellulolytic enzymes in situ on never-dried native cellulose films. Cellomonas fimi, CenA was used as a model enzyme for proof of concept experiments and for the identification of different enzyme action on different cellulose structures. Inactive and active Trichoderma reesei enzymes EGI and CBHI were studied to disentangle the action of the cellulose binding domain from the catalytic domain.
A novel procedure, volume analysis, was developed to quantify changes in cellulose fibers as a result of this action. Volume analysis was used to compare fibers in different experiments (with different structural features and enzymes) regardless of where the change in the fiber occurred. The site-specific nature of cellulose-enzyme interactions is accessible using this analysis technique. Additionally, the reported volume change reflects a change in mass that is of interest for industrial purposes.
From inactive CBHI action there was no distinguishable change between enzyme action on defect or crystalline regions of the cellulose fiber. From the active enzyme results a quantifiable degradation event was measured. Digestion was initially quick then after one hour the volume plateaued. The crystalline cellulose region plateaued at -20 ± 1% and the defect region at -31 ± 2%.
The inactive EGI enzyme was found to have significant non-hydrolytic action on insoluble cellulose fibers. There was more significant swelling effect on the defect than the crystalline regions of the cellulose fiber. From the active EGI results a quantifiable degradation event was measured followed by swelling events. Degradation was initially quick with the total mass loss occurring within the first hour of the experiment. The volume then increased as the enzyme induced swelling of the fiber structure. The extent of degradation and swelling is structure limited with more disordered regions showing larger decreases in volume and predominantly crystalline regions showing mainly swelling events.
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