The renewable energy industry continues to expand at a rapid pace. New advances in cellulosic ethanol technologies have the potential to reduce our dependency on foreign oil. The evolution of these new biofuel markets could have significant effects on future production levels, market prices, and world trade levels for various agricultural commodities. Alternative scenarios involving new biofuel technologies, primary factor availability, and government policy will result in very different outcomes for the agricultural economy. The interactions of current and new biofuel technologies, including conventional ethanol production (from corn grain) and cellulosic ethanol production (from corn stover and switchgrass), and the agricultural economy were examined in a general equilibrium framework. Various outcomes were examined with attention primarily focused on (1) trade offs among competing uses of agricultural commodities, (2) changes in the output of major agricultural producers competing with the U.S., (3) effects on the livestock industry, (4) profitability of the agricultural industry, (5) changes in input costs, including land rents, and (6) changes in land use patterns. Results indicated that advances in cellulosic ethanol technology led to less grain ethanol production and more stover ethanol production in the United States. The production of switchgrass ethanol was not economically feasible under any scenario, which was expected due to the availability of lower priced corn stover. Overall, it was expected that a decrease in the costs of cellulosic ethanol production would lead to a higher increase in total U.S. ethanol production than actually occurred. As a result, the effects on the world economy were smaller than expected.

Thesis advisor: Michael J. Naughton / The nanoscale morphology of metals can enable special functionality in plasmonic and electrochemical devices, with applications in energy conversion and storage, sensors, and computers. In particular, sharp edges on metal nano and microstructures are understood to affect the density of electrons on the metal surface. The associated concentration of electric field can concentrate surface plasmon polaritons (SPPs) and enable waveguiding of the SPPs, as we show in this thesis for sharp ridges along aluminum nanowires. Also important is the presence of facets on the metal structures, which determines the orbitals that electrons occupy on the metal surface. Changes in both the electron density and orbitals can affect the binding of molecules to the metal, which can improve reaction kinetics in catalysis. We demonstrate this on gold dendrite and plate electrocatalysts for CO2 electrolysis. Regarding metal nanostructure fabrication, electrochemical deposition and corrosion have demonstrated promising control over the morphology, including the topography, crystallinity, grain boundaries, and crystal faceting. This is important, because existing methods for metal nanostructure fabrication can only produce a circumscribed assortment of morphologies. In contrast, semiconductors and insulators have many new deposition techniques that produce a wide range of controlled morphologies. Of further appeal, electrochemical techniques are solution-based and typically operate at room temperature and pressure, allowing facile scale-up to industrial production. Here we demonstrate and discuss the mechanisms of two new techniques, which produce the aluminum nanowires and gold dendrites and plates discussed above. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

An experimental study of the effects of turbulent flow regime on the flame structure is conducted by using perforated-plate-stabilized hydrogen-piloted lean premixed methane/air turbulent flames. The underlying non-reacting turbulent flow field was investigated using two-dimensional three-components particle imaging velocimetry (2D3C-PIV) with and without three perforated plates. The non-reacting flow data allowed a separation of the turbulent flow regime into axial velocity dominated and vortex dominated flows. A plate with 62\% blockage ratio was used to represent the stream-dominant flow regime and another with 86\% blockage ratio was used to represent the vortex-dominant flow regime. OH laser-induced fluorescence was used to study the effects of the turbulent flow regime on the mean progress variable, flame brush thickness, flame surface density, and global consumption speed. In comparison with the stream-dominant flow, the vortex-dominant flow makes a wider and shorter flame. Also, the vortex-dominant flow has a thicker horizontal flame brush thickness and a thinner longitudinal flame brush thickness. Especially, the horizontal flame brush thickness for the vortex-dominant flow does not follow the turbulence diffusion theory. Then, the vortex-dominant flow shows a relatively constant flame surface density along the stream-wise direction, while the stream-dominant flow shows a decreasing flame surface density. Lastly, the vortex-dominant turbulent flow improves the consumption speed in comparison to the stream-dominant turbulent flow regime with the same velocity fluctuation level.

Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / During the past 10 years, ethanol production in the United States has grown exponentially. From 2000 to 2009 U.S. ethanol production increased from 1.6 billion gallons annually to 10.8 billion gallons annually. In 2010, U.S ethanol production increased by 23 percent from 2009 to 13.23 billion gallons. The increase in ethanol production was due to lawmakers reacting to skyrocketing oil prices by implementing a Renewable Fuels Standard (RFS) in 2005 and expanding the RFS in 2007. The RFS requires the use of specified amounts of biofuels, such as ethanol, through the year 2022. The creation of the RFS represented a step beyond lawmakers’ usual policy of using the tax code to promote ethanol production. There is a long history of encouraging ethanol production by using the tax code, but the implementation of a biofuels mandate is new and therefore there is not a great deal of research on the effects of such a policy. This study analyzes U.S. oil, unleaded gasoline, corn and ethanol prices dating back to 1985 to determine the impact that the RFS has had on corn prices. The key question answered is whether the creation and expansion of the RFS has brought the instability of the oil market into the corn market. The prices that an ethanol plant in western Kansas paid for the grain it used to produce ethanol and the price that the plant received for the ethanol that it produced are also analyzed. The plant began operation in January 2004, so it is possible to analyze the grain and ethanol prices both before and after the implementation and expansion of the RFS. To study the impact of the RFS creation and expansion, the prices were analyzed to see if there was an increase in the correlation after the creation and expansion of the RFS. Regression analysis of the national corn prices and the prices that Western Plains Energy paid for the grain that it used to produce ethanol; and regression analysis of the national price of ethanol and the price that Western Plains Energy sold its ethanol for were also used to study the impact of the RFS. Finally, the vector autoregression (VAR) model is used to analyze the dynamic relationships between the variables in the system: corn price, oil price, ethanol price and unleaded gasoline price. The analysis of the correlation reveals that both at the national and plant level grain and oil prices track much more closely together after the creation and then expansion of the RFS. The VAR reveals that there is some relationship between corn and oil prices contemporaneously. The correlation matrix of residuals reveals that there is not a strong correlation between national corn and oil prices. The results suggest the need for greater research in this area. The creation and expansion of the RFS represented a step into uncharted territory and the consequences are still not known.

The global problems of climate change, by the emissions of CO2 have over the past decenniums, led to a development of new innovations of renewable energy technologies, with the goal to phase out fossil fuels such as coal and oil. Many forms of renewable energy have already solved part of the energy consumption problems, but there are still large energy intensive industries that rely heavily on fossil fuels. One possible renewable product that could phase out fossil fuels in these industries is the black pellet, which is a processed bioenergy product. If commercialized, the black pellet could change major parts of the industry, thus making it a radical innovation.   One alternative to produce the black pellet is by using the torrefaction technology. The torrefaction technology has a historical record of many failed introductions. The step from pilot production to full scale commercialization is problematic in many ways, especially for a smaller developer. This study is focusing on the external commercialization problems for a radical innovation, the product black pellet and the technology torrefaction. The thesis aim to understand which these external barriers are for a torrefaction developer in Sweden and to answer our research question:   “What is the industry specific external barrier for a new entry-firm to commercialize black pellet with torrefaction technology?”   The theoretical framework is structured in two parts. The first one has a broad focus of theories regarding external barriers for commercialization of radical innovations, with a focus on small- and medium size enterprises. The second part focuses on general effects of industry structure and these two parts are combined in a conceptual theoretical framework. The findings in the study are based on empirical data collected through a total of six interviews with a supplier of torrefaction and black pellet, potential customers and market experts in Sweden.   The study’s analysis combines the theoretical and empirical data together with the industrial chapter, to create an understanding of the external barriers to commercialize black pellet with torrefaction technology. From the analysis we have understood many barriers, which could be summarized in four main barriers; lack of credibility, political incitements, strategic leadership and the costs of commercialization.   The answer to our research question, regarding the industry specific external barrier within the case of torrefaction and black pellet, is that black pellet and especially the torrefaction technology suffers from a lack of credibility by the actors in the market. From this answer, we have contributed with extended theoretical insights, that failures by previous actors create an external barrier for the current and future actors in their commercialization of a new technology.

In the realm of class 8 trucking, fuel economy and emissions compliance are becoming the driving force for development of new heavy-duty direct injected (HDDI) diesel engine technologies. Current production engines in this class convert around 40% of the fuels energy into usable work while the unused potential transfers to the environment as excess heat energy. Current OEMs are working toward decreasing this heat loss and improve engine efficiency and emissions. Quantifying the energy lost by component and system highlights the areas that demand the most attention. By studying test cell data of heat rejection on a production Cummins ISX engine and using the data to calibrate an engine model for the simulation software GT-Suite, heat rejection values and the components which transfer the energy are exposed. The simulation software provides energy transfer by both system and component type. The results reveal that 10% of engine total heat rejection (THR) is transferred through the cylinder wall to the engine coolant system. When the heat imparted on the cylinder wall is broken up by component, the piston rings contribute nearly as much heat into the liner as the combustion gas.

Analytical modeling of the root cause of cylinder-to-cylinder variation and the impact on CO2 emission caused by the reduction in engine efficiency <br>

<div>Currently, fossil resources dominate fuel and chemical production landscape. Besides concerns related to the ever-increasing greenhouse gas emission, fossil resources are also limited. In a petroleum-deprived future, sustainably available biomass can serve as a renewable carbon source. Due to its limited availability, however, this biomass resource must be utilized and converted effciently to minimize carbon losses to undesirable by-products. A modeling and optimization approach that can identify optimal process congurations for chemical and fuel production from biomass using stoichiometric and thermodynamic knowledge of the underlying biomass reaction system is proposed in this dissertation. Several case studies were performed with this approach, and the outcomes found agreement with reported experimental results. In particular, a case study on fast-hydropyrolysis vapor of cellulose led to the discovery of new reaction route and provided insights in comprehending the formation of experimentally observed molecules. The modeling and optimization approach consists of two main steps. The rst step is the generation of the search space and the second step is the identication of all optimal reaction routes.</div><div><br></div><div><div>For the rst step, literature review and automated reaction network generator are employed to identify all possible processes for biomass conversion. Through literature review, yield data on processes that generate biomass-derived molecules are collected. As these biomass-derived molecules often possess multiple functional groups, utilization of automated reaction network generator, which considers a set of biomass-derived molecules and reaction rules, enables generation of all possible reactions. In this work, an automated reaction network generator tool called Rule Input Network Generator is utilized. Using this generated search space, a mathematical optimization problem, which identies the optimal reaction network, is constructed. For the second step, the optimization problem identies all reaction routes with the minimum number of reactions for a given set of biomass and target products. This formulation constructs a process superstructure that contains processes that generate biomass-derived molecules and all possible reactions from biomass-derived molecules. In this optimization problem, the main constraint for the reaction is its thermodynamic favorability within a certain temperature range. Using optimization solver, optimal solutions for this problem are obtained.</div></div><div><br></div><div><div>Using this developed approach, a case study on upgrading fast-hydropyrolysis vapor of cellulose to higher molecular weight products was investigated. Levoglucosan and glycolaldehyde are major components from fast-hydropyrolysis of cellulose. This approach identied a reaction route that can upgrade these molecules to hydrocarbons with carbon number ranging from eight to 12 and this route has not been reported in the literature. The coupling of levoglucosan and glycolaldehyde requires a key intermediate, levoglucosenone, which is identied by this approach. Preliminary experimental results suggest that the proposed reactions are feasible and this serves as another validation for this approach. Other potential pathways to not only branched alkanes, but also substituted cycloalkanes and aromatics, were also identied. Molecules with those structures have been observed experimentally, and potential pathways to those molecules can provide insights for experimentalists as to how these products can form and which intermediates may lead to their formations. This approach has not only revealed unknown reaction routes, but also provided insights for experimentalists for analyzing complex systems.</div></div><div><br></div><div><div>Toward reduction of carbon losses toward char during fast pyrolysis, potential pathways toward char formation during fast pyrolysis were proposed. Investigating proposed char precursors identied using mass spectroscopy, several potential pathways toward the formation of these char precursors were obtained, which include initial insights to the potential driving force for the formation of these char precursors and, ultimately, char itself.</div></div><div><br></div><div><div>Going beyond fast pyrolysis, primary processes that have been developed in C3Bio along with several existing primary processes were considered in order to identify optimal biorenery congurations. This approach identied biorenery congurations with carbon effciencies from 60-64%. These congurations generate not only fuel type molecules, but also commodity chemicals that are being produced in a traditional renfiery. In addition, it is capable of providing these products at their current relative production rates in the United States. Other studies on biorefinery reported only 25-59% carbon effciency and generated mostly fuel-type molecules. Therefore, this approach not only indicates the appropriate reaction sequences, but also optimal utilization of carbon in biomass-derived molecules. This dissertation provides an initial roadmap toward sustainable production of fuels and chemicals from lignocellulosic biomass.</div></div><div><br></div><div><div>Considering that the transition to renewable energy is gradual and shale resource is an abundant fossil resource in the United States, opportunities to valorize shale gas condensate are explored. Recent shale gas boom has transformed the United States energy landscape. Most of the major shale basins are located in remote locations and historically non-gas producing regions. Therefore, many major shale basins regions are lacking the infrastructure to distribute the extracted gas into the rest of the US and particularly the Gulf Coast region. In this dissertation, shale gas catalytic upgrading processes were synthesized, designed, and simulated using Aspen Plus Simulation. Using Aspen Economic Analyzer, preliminary techno-economic analysis and evaluation of its economic potential were assessed at varying scales to assess its impact on the</div><div>United States chemical industry landscape.</div></div>

Submitted by (edna.saturno@ufrpe.br) on 2017-02-17T15:55:36Z No. of bitstreams: 1 Rebeca Ferreira Lemos Vasconcelos.pdf: 270482 bytes, checksum: 094a646397559de7fef19a7c96db3c1f (MD5) / Made available in DSpace on 2017-02-17T15:55:36Z (GMT). No. of bitstreams: 1 Rebeca Ferreira Lemos Vasconcelos.pdf: 270482 bytes, checksum: 094a646397559de7fef19a7c96db3c1f (MD5) Previous issue date: 2012-12-20 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Currently there is much debate about the production of biodiesel and ethanol, and new technologies studied for obtaining oil, for example, microalgae, which are one of the most effective systems for conversion of solar energy into organic compounds. These compounds are mostly carbohydrates, proteins and lipids. The major difficulty in the production of biofuels through the harvesting of algae is therefore still quite expensive methods such as centrifugation, flocculation, sedimentation and filtration. This study aims to evaluate the effect of different flocculants in obtaining the biomass of Chlorella vulgaris (Chordat). The experimental design was completely randomized, with four bioassays, in which the first three comprised four treatments and three repetitions each composed of different treatments molalitys (0.1 M, 0.3 M, 0.5 M and 0.9 M) for flocculating agents sodium hydroxide, ferric chloride and aluminum polychloride. Subsequently fourth bioassay was performed which consisted of three treatments and three replications, where treatments consisted of different flocculating agents (sodium hydroxide, poly aluminum chloride and ferric chloride), in the same molar concentration (0.5 M). For experimentation microalgae of the species C. vulgaris were primed in experimental units, transparent materials with a volume of 2000 mL, reaching the seventh day the exponential phase of their growth curve obtained in previous tests. From the seventh day was started with a flocculation concentration algal average 1085 x 104 cel. mL-1, with a temperature of 22 ± 2 ° C and pH 7.0, constant aeration and light intensity of 2000 lux. Was added in experimental units 1 ml of standard solutions of flocculating agents then microalgae were subjected to moderate stirring continuously for 30 seconds. The pH variation data were interpreted by Analysis of Variance (ANOVA) followed by Tukey's test for comparison of means at the level of 5%. Analysis of the data verified that all treatments were different (P <0.05), but the use of sodium hydroxide as the flocculating agent obtained best results, we can conclude that where sodium hydroxide is the most suitable for flocculating agent quickly raise the pH of the culture (11.00 ± 0.37), thus leading to cell clumping and settling in a short time, and greater weight of biomass compared to other treatments. / Atualmente existe muita discussão sobre a produção de Biodiesel e etanol, sendo estudadas novas tecnologias para a obtenção de óleo, como por exemplo, as microalgas, que são um dos mais eficientes sistemas de transformação de energia solar em compostos orgânicos. Esses compostos são em sua maioria carboidratos, proteínas e lipídeos. A grande dificuldade para a produção de biocombustíveis através das algas é a colheita, pois ainda são métodos bastante onerosos, como a centrifugação, floculação, sedimentação, e filtração. Este trabalho tem como objetivo avaliar o efeito dos diferentes floculantes na obtenção da biomassa da Chlorella vulgaris (Chordat). O delineamento experimental adotado foi o inteiramente casualizado, composto por quatro bioensaios, nos quais os três primeiros compreendiam quatro tratamentos e três repetições cada, sendo os tratamentos compostos por diferentes molalidades (0,1M, 0,3M, 0,5M e 0,9M) para os agentes floculantes hidróxido de sódio, cloreto férrico e policloreto de alumínio. Posteriormente foi realizado o quarto bioensaio o qual era composto por três tratamentos e três repetições, onde os tratamentos consistiram em diferentes agentes floculantes (hidróxido de sódio, policloreto de alumínio e cloreto férrico), na mesma concentração molar (0,5M). Para a experimentação as microalgas da espécie C. vulgaris foram condicionadas em unidades experimentais, materiais transparentes com volume útil de 2000 mL, atingindo no sétimo dia a fase exponencial de sua curva de crescimento obtida em testes anteriores. A partir do sétimo dia deu-se início a floculação com uma concentração algal média de 1085 x 104 cel. mL-1, com temperatura de 22±2°C e pH 7,0, aeração constante e intensidade luminosa de 2000 lux. Foi adicionado nas unidades experimentais 1 mL de soluções padrão dos agentes floculantes, em seguida as microalgas foram submetidas a agitação moderada constante durante 30 segundos. Os dados da variação de pH foram interpretados por meio da análise de variância (ANOVA) seguido pelo teste Tukey para comparação de médias ao nível de 5%,. Após análise dos dados verificou-se que todos os tratamentos foram diferentes (P<0,05), porém a utilização do hidróxido de sódio como agente floculante obteve melhor resultado, onde podemos concluir que o hidróxido de sódio é o agente floculante mais indicado por elevar mais rapidamente o pH da cultura (11,00±0,37), ocorrendo assim a aglutinação e a decantação das células em um curto espaço de tempo, e maior peso da biomassa em relação aos outros tratamentos.

Historically, it has been negative to be dependent on only one resource, in the current situation this resource represents oil. The oil dependence is primarily in the transport sector. From a Swedish perspective oil is an energy resource mainly used in the transport sector. Much of the oil that Sweden imports has its origin in the North Sea. The oil production in the North Sea has however begun to decline, which highlights that oil is a finite resource. This also means that Sweden has to start importing oil from other countries, which may affect the Swedish energy security as these countries may be geographical further away and also be more political instable. It also implies that a transition from oil to renewable fuel within the transport sector is essential. The aim of this thesis is to study how Swedish energy security is affected by the oil production volumes in The North Sea. The thesis is divided into three parts. The first part consists of updating historical data from recent analyses on North Sea oil production (i.e. Höök and Aleklett, 2008 and Höök et al., 2009a), and also create updated forecasts of future oil production for both Denmark and Norway. The second part investigates how production declines in the North Sea affect the Swedish oil imports. The final section examines how a shift to renewable fuels within the transport sector is possible, with a focus on natural resources. Finally some recommendations are presented on how Sweden could increase their energy security regarding the transport sector by introducing renewable fuels.