No description available.

The requirement of bringing an outside coolant source to run through the seals of a multiphase pump has always been a costly endeavor. Using a separator to extract liquid from the exhaust of the pump to use as a coolant is often more expensive than providing an outside source of coolant. This research proposes a cost effective separator design which efficiently separates the liquid from gas, while maintaining a high enough residence time to remove any gas entrainment, and separates only the seal flush requirement by letting any excess liquids carryover with the gas. Conventional multiphase separators operate by substantially decreasing the velocity of the mixture, which reduces the drag force put forth by the gasses and allows gravity to force the liquids downward. Gas-Liquid Cylindrical Cyclones (GLCCs) operate by increasing the velocity of the mixture, using radial force to separate liquids and gasses. This technique requires a smaller diameter vessel to achieve separation. The separator in this research uses gravity as the separation force while maintaining a pipe diameter similar to the GLCC. This way, only standard pipe and pipe fittings are used. The effectiveness of this design is measured two ways. First, efficiency is studied at varying gas volume fractions (GVFs), velocities, pressures, and pipe diameters. Second, the length of air entrainment (LAE) is measured at the same varying conditions. The efficiency and air entrainment studies provide design recommendations to accommodate seal flush requirements and size limitations. The following investigation also offers further areas of research to improve the understanding and modeling of using standard pipe and pipe fittings to create more effective design equations.

No description available.

No description available.

No description available.

The battery separator is a component of the conventional battery that for long has been overlooked. Just because it’s the only inactive component, doesn’t mean it’s any less important for the battery cell. Recent trends point to an immense growth of the electrical vehicle-industry, and by so, also the lithium-ion battery separators market. This is because the lithium-ion battery is the most common battery type in commercial electrical vehicles. In one of the major manufacturing processes of the separator, mineral oil is used, to achieve a porous film. This study aims to evaluate different oils interaction with the polymer resin in the manufacturing process. Since most oils used in the battery separator industry today use paraffin rich oils, oils with different naphthenic content is tested to find correlations between the oils properties and the crystallinity or the porosity. No correlations for either the porosity or the crystallinity could be made to the oil’s properties. The images taken with the SEM was not enhanced enough to study the pores themselves or the pore structure of the films. For future studies it is recommended to collect more data to identify outliers so more accurate values are obtained. The methodology needs to be verified to ensure the procedure is reproducible. For the study of the pores and the pore structure, an FE-SEM should be used to achieve greater quality enhancement images on the surface of the films. / Batteri separatorn är en komponent i det konventionella batteriet som länge har förbisetts. Bara för att den är en inaktiv komponent, betyder inte att den är mindre viktig för battericellens prestation. Trender idag pekar mot en enorm tillväxt inom elbils-industrin, och med det även litium-jon batteriseparatorns marknad. Det är för att litium-jon batteriet är det batteriet som vanligen används kommersiellt idag i elbilar. I en av de två stora industriella tillverkningsprocesserna används olja för att åstadkomma en porös film. Denna studie syftar på att utvärdera olika oljors interaktion med polymeren i denna tillverkningsprocess. Eftersom de flesta batteriseparator-industrier idag använder paraffinrik olja så testas oljor med olika mycket naftalensikt innehåll för att hitta korrelationer mellan oljornas egenskaper och kristalliniteten eller porositeten hos filmerna. Inga korrelationer för porositeten eller kristalliniteten kunde göras till oljornas egenskaper. Bilderna tagna med SEM var ej tillräckligt förstorade för att kunna studera vare sig porstorleken eller porstrukturen hos filmerna. För framtida studier rekommenderas att samla in mer data för att kunna utskilja ”outliers” i datan, för att erhålla mer korrekta värden. Metodiken måste även verifieras för att säkerställa att proceduren är reproducerbar. För att studera porerna och porstrukturen, borde en FE-SEM användas för att få mer förstorade bilder med bättre kvalité på filmernas yta.

A better understanding of several mineral processing devices and applications was gained through studies conducted with mathematical analysis tools. Linear circuit analysis and population balance modeling were utilized to remedy inefficiencies found in a number of popular mineral processing water-based unit operations. Improvements were made in areas, including unit capacity and separation efficiency. One process-engineering tool, known as linear circuit analysis, identified an alternative coal spiral circuit configuration that offered improved performance while maintaining a reasonable circulating load. In light of this finding, a full-scale test circuit was installed and evaluated at an existing coal preparation facility. Data obtained from the plant tests indicate that the new spiral circuit can simultaneously reduce cut-point and improve separation efficiency. A mathematical population balance model has also been developed which accurately simulates a novel hindered-bed separator. This device utilizes a tangential feed presentation system to improve the performance of conventional teeter-bed separators. Investigations utilizing the mathematical model were carried out and have predicted solid feed rates of up to 71 tph/m² (6 tph/ft²) can be achieved at acceptable efficiencies. The model also predicts that the unfavorable impact of operating at low feed percent solids is severely reduced by the innovative feed presentation design. Tracer studies have verified that this system allows excess feed water to cross over the top of the separator without entering the separation chamber, thereby reducing turbulence. A hindered-bed separator population balance model was also developed whose results were utilized to improve the efficiencies encountered when using a teeter-bed separator as a mineral concentrator. It was found that by altering the apparent density of one of the feed components, the efficiency of the gravity separation could be greatly improved. These results led to the development of a new separator which segregates particles based on differences in mass after the selective attachment of air bubbles to the hydrophobic component of the feed stream. Proof-of-concept and in-plant testing indicate that significant improvements in separation efficiency can be achieved using this air-assisted teeter-bed system. The in-plant test data suggest that in some cases, recoveries of the plus 35 mesh plant feed material can be increased by more than 40% through the application of this new technology. / Ph. D.

Lithium-ion battery (LIB) is widely utilized in many modern applications as energy sources. Numerous efforts have been dedicated to increasing electrochemical performances, but improvement on battery safety remains a visible challenge. While new electrode materials have been developed, advancement in new separator for LIB has remained relatively slow. Separator is the polymeric porous material that physically separates electrodes and allows free flow of ions through its structure. It is electrochemically inactive but essential for avoiding thermal runaway conditions. Besides its crucial functions, separator has been known as the mechanically weakest component. Structural battery is a new approach that employs multifunctional material concept to use LIB as load-bearing material to minimize the weight of the complete system and maximize the efficiency. Separator materials are required to have good thermal stability, battery chemistry, and mechanical performance. This work aims at creating electrospun membranes with improved thermal resistance, structural integrity and moderate ionic conductivity as the next generation LIB separators. Electrospinning process is known as a versatile and straightforward technique to fabricate continuous fibers at nano- and micro- scales. The electrospinning process employs an electrostatic force to control the production of fibers from polymer solutions. Solution and process parameters, including type of polymer and solvent system, concentration of polymer solution, acceleration voltage, and solution feed rate, have been studied to achieve the desirable membrane properties. In this report, the electrospinning parameters affecting morphology and corresponding properties of electrospun membranes, electrospun polymer composite and polymer-metal oxide composite membranes for structural battery applications will be discussed.

O presente estudo visa dar luz sobre fenômenos ainda pouco explorados que ocorrem durante a estratificação em leitos de jigagem, bem como sobre novas possibilidades de aplicação da técnica. Por meio de testes com misturas de agregados em jigues hidráulico e pneumático descontínuos, foi pela primeira vez examinada a ocorrência de convecção granular em jigues. Os fatores envolvidos em sua formação e a influência sobre a estratificação foram analisados em detalhes. Do mesmo modo, foi examinada a influência da granulometria do leito sobre a estratificação em jigues pneumáticos e a possibilidade de uso do mesmo como um equipamento multi-separador. Os resultados revelam a existência de um fluxo ordenado e estacionário de partículas durante a pulsação do leito, ascendente na porção central e descendente nas bordas do jigue, de modo similar ao fluxo convectivo descritos na literatura para leitos vibrados mecanicamente. Este fluxo convectivo gerou uma distorção no rearranjo do leito estratificado, dando origem a um perfil horizontal de estratificação no qual as partículas leves se concentraram nas bordas e as partículas densas se concentraram preferencialmente na zona central dos estratos. Com base nos resultados, um mecanismo de formação do fluxo convectivo e um modelo preditivo do rearranjo do leito foram propostos. Observou-se também que a diminuição da granulometria e o aumento da distribuição de tamanho dos constituintes do leito teve um efeito positivo sobre a estratificação. Os resultados sugerem que isto pode estar em parte relacionado a maior compactação do leito quando da presença de partículas de menor tamanho. Também, resultados experimentais demonstraram a possibilidade de uso do jigue pneumático para realizar a operação conjunta de separação de materiais rochosos e não rochosos em um único estágio. O desempenho global na remoção de contaminantes não-rochosos foi similar ao de separadores pneumáticos e sistemas de "sorting" automático descritos na literatura. Ainda, a quantidade inicial de contaminantes no sistema teve um efeito desprezível sobre o desempenho. Os resultados obtidos, em particular aqueles relacionados à convecção granular, fornecem novas perspectivas a respeito dos fenômenos envolvidos na estratificação em jigues. Ainda, benefícios práticos podem ser extraídos a partir dos resultados da análise do efeito da granulometria sobre a estratificação e do uso de jigues pneumáticos como multi-separadores. / This study aims to shed some light on some unclear phenomena that occurs during particle stratification in jigs as well as on new possibilities of application of jigging technique. For the first time, the occurrence of granular convection in jigging beds was analyzed by considering the case of hydraulic and pneumatic jigs operating with mixtures of aggregates. The elements involved in the pattern formation and its influence on bed stratification were analyzed in detail. The influence of particle size distribution on bed stratification and the possibility of using pneumatic jigging as a multi-separator were also examined. The experimental results reveal the existence of a steady, ordered flow of particles over bed pulsation, in which particles move upward in the center of the jig bed and downward along the walls of the jig container, similarly to the circulation patterns reported in the literature. The convection gave rise to a distortion in the particle rearrangement, engendering the formation of a horizontal stratification profile in which light particles tended to be concentrated along the walls while dense particles tended to be concentrated preferentially in the center portion of the strata. On the basis of the experimental results, a mechanism of pattern formation and a prediction model were proposed. The results also revealed that the decrease of the particle size and the increase in the particle size distribution had a positive influence on stratification extent. It was suggested by the results that this behavior can be related to the higher bed compaction due to the presence of smaller particles in the bed. Also, experimental results indicated the technical feasibility of the combined use of pneumatic jigging for the removal undesired non-stony materials together with the bed stratification in only one single stage. The reported separation efficiency in the removal of low-density materials was comparable to those of air classifiers and automatic sorting systems. Also, the initial content of contaminants seemed to have a negligible effect on the separation performance. The results obtained, in particular those related to the granular convection, provides new perspectives about the phenomena involved in stratification by jigging. Moreover, practical benefits can be obtained from the results about the influence of particle size on bed stratification and about the usage of pneumatic jigging for multi-separation.

Proton exchange membrane (PEM) fuel cells, with low operating temperatures and high power density, are a reasonable candidate for use in mobile power generation. One large drawback to their use is that their fuel reformer requires not only fuel but also water, thereby requiring two separate reservoirs to be available. PEM fuel cells exhaust enough water in their oxidant stream to potentially meet the needs of the fuel reformer. If this water could be recovered and routed to the fuel reformer it would markedly increase the portability of PEM fuel cells. The goal of this research was to test a previously designed axial flow moisture separator. The separator was employed in a test bed which utilized compressed, heated air mixed with steam to simulate the oxidant exhaust conditions of a 25 kW PEM fuel cell. The simulated exhaust was saturated with water. The mixture was expanded through the turbine side of an automotive turbocharger, which dropped the temperature and pressure of the mixture, causing water to condense, making it available for separation. The humid air mixture was passed over an axial flow centrifugal separator and water was removed from the flow. The separator was tested in a variety of conditions with and without passing chilled water through the separator. The axial separator was tested independently, with a flow straightener preceding it, and with a commercially available centrifugal moisture separator in series following it. It was shown that cooling makes a significant impact on the separation rate while adding a flow straightener does not. Separation efficiencies of 19% on average were experienced without cooling, while efficiencies of 50% were experienced with 3.1 kW of cooling. The separation efficiency of the two moisture separators combined was found to be 31.7% which is 165% that of the axial separator alone under uncooled conditions.