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1
Schmitt, Vivien. "Investigation expérimentale et numérique d'un ouvrage de séparation particulaire en assainissement." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAD023/document.
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Dans le cadre de cette thèse, un ouvrage de type séparateur hydrodynamique est étudié pour répondre aux problématiques environnementales liées aux déversements de macro-déchets en mer. La première partie est destinée à l’analyse du fonctionnement hydraulique de l’ouvrage et son aptitude face au colmatage sur un pilote en laboratoire. Les données collectées vont ensuite permettre la validation d’une approche numérique capable de simuler l’écoulement. Cette technique est par la suite utilisée pour optimiser l’écoulement et la forme de la grille. Nous avons démontré, à partir de simulations numériques, l’intérêt d’une grille de type métal déployé pour obtenir des phénomènes d’agitations turbulentes et de gradient de pression important à l’amont de la grille. Ces phénomènes favoriseraient ainsi la dispersion des polluants et limiteraient les phénomènes de colmatage. La dernière partie de ce travail a été d’étudier le fonctionnement d’un ouvrage grandeur nature et d’observer son efficacité<br>The installation of hydraulic structures to separate particles is a key element to improve the quality of water bodies. This PhD work focus on the study of a hydrodynamic separator used to capture large wastes before their discharge into the see. Tangential separation mechanism along a screen is used in this device. The first part of the work consists in studying the hydraulic behavior and the clogging effectiveness of the device with laboratory experiments. A CFD multiscale approach was developed in this work to optimize the shape of the screen in order to avoid clogging. This method, validated against experimental data, allows us to predict that expanded metal stripes are useful to develop turbulence and pressure gradients upstream the screen. This hydrodynamic phenomenon favor particles and pollutants ejection near the apertures. The last part of the work was to study the hydrodynamic behavior and the real efficiency with in situ experiments
2
Ortega-Rivas, Enrique. "Dimensionless scale-up of hydrocyclones for separation of concentrated suspensions." Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253983.
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Yuan, Huixin. "Hydrocyclones for the separation of yeast and protein particles." Thesis, University of Southampton, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242214.
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Yawson, Selina Kuukuwa. "Dairy manure treatment using solid-liquid separation and microwave enhanced advanced oxidation process." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29232.
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Dairy manure treatment, using solid-liquid separation and microwave enhanced advanced oxidation process (MW/H₂O₂-AOP), was investigated. The objectives of the research were to determine: 1) the nutrient and metal composition of solid and liquid fractions of raw dairy manure following solid-liquid separation, 2) the effects of MW/H₂O₂-AOP operating factors of temperature, hydrogen peroxide (H₂O₂) dosage, acid concentration and heating time on sugar production and nutrient release from solid dairy manure.
Solid-liquid separation of raw dairy manure, using a 1mm laboratory sieve, showed that solid fractions had a higher composition of TS and volatile solids (VS), while the liquid fractions were richer in nutrients and metals. Laboratory separation by screening alone was not effective in removing high amounts of nutrients and solids from the raw manure.
Screening experiments were conducted using cellulose fibers to study the effects of temperature, acid concentration, H₂O₂ dosage and heating time on sugar production, with the aim of applying the results to dairy manure lignocellulosic material. Sugar production increased when acid concentration was increased from 1% to 3%, but decreased with an increase to 10%. More sugar was produced at 160°C compared to 120°C. Sugar production decreased with increasing time.
Microwave irradiation of solid dairy manure at pH 2, temperatures of 80, 120 and 160°C, H₂O₂ dosages of 0 to 0.50 mL, and heating times of 10 to 20 min, showed that more sugars were released at higher temperatures. Temperature and hydrogen peroxide dosage were identified as the most important factors affecting solubilization of phosphorus and ammonia. Subsequently, a two-stage acid hydrolysis process, using MW/H₂O₂-AOP, was used to investigate sugar production and solubilization of phosphorus and ammonia from solid dairy manure at: 3% acid concentration, 120 and 160°C, 0 and 2 mL H₂O₂ and heating times of 20 and 60min. To enhance sugar production from solid dairy manure, the microwave should be operated at higher temperatures and shorter heating times with no H₂O₂. For ammonia and phosphorus solubilization, higher temperatures and longer heating times, in the presence of H₂O₂, would be advantageous.
MW/H₂O₂-AOP is therefore an efficient means for treating diary manure for nutrient recovery.
5
Strandh, Jenny. "A study of solid and liquid inclusion separation at the steel-slag interface." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-307.
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Kholany, Mariam Achraf Mohamed Bahie El Din El. "Enantioselective separation of chiral compounds using aqueous biphasic systems and solid-liquid biphasic system." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22708.
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Mestrado em Biotecnologia - Industrial e Ambiental<br>Tipicamente, apenas um dos enantiómeros é responsável pelo efeito pretendido de um fármaco, sendo que o outro pode levar a respostas menos potentes ou até mesmo indesejadas. As entidades reguladoras praticam políticas restritas em relação à comercialização de fármacos como misturas racémicas. Assim, a indústria farmacêutica tem enfrentado desafios relacionados com o desenvolvimento de métodos para produção de fármacos oticamente puros. No entanto, e considerando a dificuldade acrescida na produção de enantiómeros puros por síntese direta, a síntese de misturas racémicas seguida da sua purificação surge como uma alternativa mais barata, simples e flexível.
Os sistemas aquosos bifásicos (SABs) e os sistemas de duas fases sólida-líquida (SDFSL) são técnicas alternativas mais biocompatíveis que têm sido utilizados como técnicas de separação enantiosseletiva de fármacos e/ou aminoácidos com enantiosseletividades bastante promissoras. Para além disso, apresentam benefícios de custo, rapidez, simplicidade e versatilidade de operação e possibilidade de aumento de escala.
Este trabalho foca-se no desenvolvimento de SABs e SDFSL constituídos por seletores quirais que possam atuar simultaneamente como solvente. Numa primeira abordagem o objetivo foi desenvolver novos SABs quirais, mais biocompatíveis, simples e eficientes. Para tal, SABs constituídos por açúcares, aminoácidos e líquidos iónicos quirais foram aplicados na resolução enantiomérica de ácido mandélico racémico. O sistema mais promissor, composto por [C1Qui][C1SO4] + K3PO4, obteve um excesso enantiomérico de -33.4%. Numa segunda abordagem, foi possível criar uma alternativa mais simples e mais eficiente recorrendo a SDFSL. Com estes sistemas, foi obtido o valor mais elevado de excesso enantiomérico deste trabalho, de 49.0%, através da precipitação enantiosseletiva do R-ácido mandélico por interação com [N4444][D-Phe].<br>Conventionally, only one of the enantiomers is responsible for the intended effect of a drug, whilst the other may lead to a less potent or even undesired response. Regulation entities are very strict regarding the commercialization of racemic drugs. Thus, pharmaceutical industry has been facing challenges related to the creation of methods to produce optically active drugs. However, considering the increased difficulty in the production of pure enantiomers by direct synthesis, the synthesis of racemic mixtures followed by their purification appears as a cheaper, simpler and more flexible alternative.
Aqueous biphasic systems (ABS) and solid-liquid biphasic system (SLBS) are more biocompatible alternatives that have been used to separate racemic drugs and amino acids with promising enantioselectivities. Furthermore, these are cost-effective, quick, simple and operationally flexible.
This work intended to develop ABS and SLBS using chiral selectors that can simultaneously act as solvents. In a first attempt, chiral ABS of better biocompatibility, simplicity and efficiency were developed. For that purpose, ABS constituted by sugars, amino acids and chiral ionic liquids (CILs) were applied for chiral resolution of racemic mandelic acid (MA). The most promising ABS was a system composed of [C1Qui][C1SO4] + K3PO4 which yielded the maximum enantiomeric excess of -33.4%. In a second approach, it was possible to create a simpler and more efficient technique resorting to SLBS. The enantiomeric excess value of 49.0% was achieved, by the enantioselective precipitation of the R-MA caused by interactions with [N4444][D-Phe].
7
Bailey, Andrew Douglas. "An exploratory investigation of crossflow microfiltration for solid/liquid separation in biological wastewater treatment." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/21915.
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This thesis contains the results and discussion of an exploratory investigation into the application of Crossflow Microfiltration (CFMF) for solid/liquid separation in biological wastewater treatment systems. The principal objective of the study was to assess the influence of CFMF on the performance of identified biological wastewater treatment systems. It was not the objective to optimise filtration performance. A literature review indicated that the crossflow mode of filtration has been widely accepted as a unit operation in the fermentation industry. The filtration mode is now being applied not only for solid/liquid separation but also for separations on a molecular and ionic level. Very few applications of crossflow filtration in the context of biological wastewater treatment solid/liquid separation are reported in the literature. The reasons for this limited experience would appear to be the scale involved and the perceived high costs; separations in the fermentation industry are usually conducted at relatively small scale (laboratory or pilot-scale) and involve high-value products, justifying high capital and operating costs. Also, the high level of separation performance attained is perhaps not necessary for many wastewater treatment applications. No doubt these reservations are largely valid. However, these arguments cannot be applied equally to all filtration methods and wastewater treatment schemes. For example, the costs of microfiltration are substantially less than ultrafiltration or reverse osmosis, and in certain cases effluents with extremely low suspended solids contents may be required. In the light of these observations an investigation of CFMF for solid/liquid separation in biological wastewater treatment systems appears justified. Two biological treatment systems were selected for study: the Upflow Anaerobic Sludge Bed (UASB) reactor and the Activated Sludge system. The envisaged benefits accruing from the application of CFMF were different in each case.
8
Menon, Sreejit Rajiv Menon. "Design and Development of 2-Functionalized Calix[4]arenes and Their Investigation in the Separation of Lanthanides." University of Toledo / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1461715995.
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Adamcewicz, Justine E. "A study on the effects of dot gain, print contrast and tone reproduction as it relates to increased solid ink density on stochastically screened images verus conventionally screened images /." Online version of thesis, 1994. http://hdl.handle.net/1850/11989.
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Du, Toit Geoff J. G. "Design and performance of BNR activated sludge systems with flat sheet membranes for solid-liquid separation." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/5061.
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Includes bibliographical references.<br>Wastewater treatment technologies have developed out of the need to protect receiving water bodies from the increasingly concentrated municipal and industrial waste streams generated through human activity. Of the methods available to clean wastewaters, biological nutrient removal (BNR) activated sludge (AS) is applied throughout South Africa and internationally as it has many advantages, notably it is cheaper to operate, does not introduce salinity into the water and is a simple and robust process. One of the key steps in the BNR AS process is the separation of biomass from the water. This is traditionally achieved by means of secondary settling tanks (SSTs), however recently the use of membranes for solid-liquid separation has gained popularity for the following reasons: Membranes are able to retain all solids and thus are insensitive to the settling characteristics of sludges, • they can be run at high concentrations and hence smaller reactor volumes are required, • membranes can produce a guaranteed high quality effluent free of pathogens and in some cases viruses too. • Additionally smaller reactor volumes and the obviation of SSTs allow a substantial wastewater treatment plant footprint reduction. Hence the combination of membranes in BNR AS is being increasingly applied. where much research has been conducted on the performance of membranes. The majority of the research has focused on the physical membrane performance, investigating the mechanisms of fouling, or on the membrane biological reactor (MBR) performance in removing organic compounds or nitrogen compounds from wastewater. There are however few case studies investigating BNR using membranes despite speculation that the inclusion of membranes may indeed affect the nature of the activated sludge biomass (Witzig et al., 2002).
11
Unadkat, Heema. "Investigation of turbulence modulation in solid-liquid suspensions using FPIV and micromixing experiments." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6377.
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The focus of this thesis is the study of turbulent solid-liquid stirred suspensions, which are involved in many common unit operations in the chemical, pharmaceutical and food industries. The studies of two-phase flows present a big challenge to researchers due to the complexity of experiments; hence there is a lack of quantitative solid and liquid hydrodynamic measurements. Therefore, an investigation of turbulence modulation by dispersed particles on the surrounding fluid in stirred vessels has been carried out, via two-phase fluorescent Particle Image Velocimetry (FPIV) and micromixing experiments. The main property of interest has been the local dissipation rate, as well as root-mean-square (rms) velocities and turbulent kinetic energy (TKE) of the fluid. Initially a single-phase PIV study was conducted to investigate the flow field generated by a sawtooth (EkatoMizer) impeller. The purpose of this study was to gain insight into various PIV techniques before moving on to more complex two-phase flows. Subsequently stereo-, highspeed and angle-resolved measurements were obtained. The EkatoMizer formed a good case study as information regarding its hydrodynamics is not readily available in literature, hence knowledge has been extended in this area. An analysis of the mean flow field elucidated the general structure of fluid drawn into the impeller region axially and discharged radially; the latter characterised the impeller stream. The radial rms velocity was considered to represent best the system turbulence, even though the tangential rms velocity was greater close to the blade; however the radial component was more prevalent in the discharge stream. Due to differences in rms velocities, TKE estimates obtained from two and three velocity components deviated, being greater in the latter case. Integral (1-D and 2-D) length scales were overestimated by the quantity W / 2 in the impeller region. Ratios of longitudinal-to-lateral length scales also indicated flow anisotropy (as they deviated from 2:1). The anisotropy tensor showed that the flow was anisotropic close to the blade, and returned to isotropy further away from the impeller. Instantaneous vector plots revealed vortices in the discharge stream, but these were not associated with flow periodicity. Alternatively, the vortex structures were interpreted as low frequency phenomena between 0-200 Hz; macro-instabilities were found to have a high probability of occurrence in the discharge stream. Dissipation is the turbulent property of most interest as it directly influences micromixing processes, and its calculation is also the most difficult to achieve. Its direct determination from definition requires highly resolved data. Alternative methods have been proposed in the literature, namely dimensional analysis, large eddy simulation (LES) analogy and deduction from the TKE balance. All methods were employed using 2-D and 3-D approximations from stereo-PIV data. The LES analogy was deemed to provide the best estimate, since it accounts for three-dimensionality of the flow and models turbulence at the smallest scales using a subgrid scale model. (Continues...).
12
Breitschuh, Birgit. "Continuous dry fractionation of milk-fat : application of high shear fields in crystallization and solid-liquid separation /." Zürich, 1998. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12605.
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Burke, Thomas A. "Modification and Validation of a Novel Solid-Liquid Separation Technique Using a Microscreen and Capillary Belt System." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1324052073.
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Zhao, Qichao. "Ionic Liquid Materials as Gas Chromatography Stationary Phases and Sorbent Coatings in Solid-Phase Microextraction." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1320963975.
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Matkar, Rushikesh Ashok. "Phase Diagrams and Kinetics of Solid-Liquid Phase Transitions in Crystalline Polymer Blends." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1189533285.
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Zhou, Ling. "DEVELOPMENT OF A UNIVERSAL POLYMERIC STATIONARY PHASE FOR SOLID PHASE EXTRACTION AND AN IONIC LIQUID MOBILE PHASE MODIFIER FOR SEPARATION OF NATIVE PROTEINS BY LIQUID CHROMATOGRAPHY." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1371503762.
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Cruz, Othon Carlos da. "Desempenho de um hidrociclione de geometria "rietema" como pré filtro para sistemas de irrigação /." Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/105302.
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Orientador: José Renato Zanini<br>Banca: Antônio Carlos Barreto<br>Banca: Tarlei Arriel Botrel<br>Banca: Luiz Carlos Pavani<br>Banca: Antônio Sergio Ferraudo<br>Resumo: Os hidrociclones são equipamentos amplamente utilizados pela indústria em processos envolvendo separação sólido-líquido, porém, ainda, pouco divulgados na agricultura irrigada brasileira. Buscou-se neste trabalho determinar a perda de carga e avaliar o desempenho de um hidrociclone de geometria "Rietema" como pré-filtro de partículas sólidas. Os testes foram realizados no Centro Federal de Educação Tecnológica de Uberaba - MG - Brasil utilizando um hidrociclone de geometria "Rietema". Este equipamento possui um diâmetro de 19,20 cm na parte cilíndrica e opera com vazões variando entre 10 m3 h-1 e 27 m3 h-1. Os materiais particulados usados em suspensão foram: solo franco-argiloso e areia de rio. Os resultados mostraram que a perda de carga máxima média foi de 52 kPa e 47 kPa para as suspensões aquosas de areia e solo, respectivamente. Seu melhor desempenho ocorreu operando com suspensão aquosa de areia, apresentando eficiência total de 92,31% para a vazão de 26,97 m3 h-1. Dentre as conclusões pode-se inferir que o equipamento avaliado é eficiente para remoção de partículas de areia, podendo ser utilizado como pré-filtro em sistemas de irrigação.<br>Abstract: The hydrocyclones are equipments widely used by industry in cases involving solid-liquid separation, but still, little reported in brazilian irrigated agriculture. The proposal of this research was to determining the head loss and evaluate the performance of a hydrocyclone of geometry "Rietema" as a pre-filter of solid particles. The tests were performed in the Centro Federal de Educação Tenológica de Uberaba - MG - Brazil using a hydrocyclone of Rietema geometry. This equipment has a diameter of 19.20 cm at the cylindrical part and operates with flows ranging between 10 m3 h-1 and 27 m3 h-1. The materials used in particulate suspension were: clay loam soil and sand from river. The results showed that the average maximum head loss was 52 kPa and 47 kPa of aqueous suspensions of sand and soil, respectively. Its best performance occurred operating with slurry of sand, presenting total efficiency of 92.31% for flow rate of 26.97 m3 h-1. Among the conclusions can be inferred that the equipment is judged effective at removing particles of sand and can be used as pre-filter in irrigation systems.<br>Doutor
18
Haupt, Petronella. "Effective solvent extraction of coal and subsequent separation processes." Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-08282007-113611.
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Thesis (M. Eng.)(Chemical Engineering)--University of Pretoria, 2006.<br>Accompanied by a CD-ROM containing Matlab programs. Includes bibliographical references. Available on the Internet via the World Wide Web.
19
Bizard, Arnaud François Marie. "Design of conical centrifugal filters : an analytical approach." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609854.
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Martins, Mónia Andreia Rodrigues. "Studies for the development of new separation processes with terpenes and their environmental distribution." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22515.
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Doutoramento em Engenharia Química<br>Os terpenos pertencem ao que é provavelmente a maior e mais diversificada
classe de produtos naturais com aplicações em vários setores devido aos seus
sabores e fragrâncias. O seu elevado número, variedade de estruturas e
complexidade química, fazem deles uma classe de compostos onde há ainda
muitos estudos a serem realizados e questões a serem respondidas tanto
sobre as suas propriedades termofísicas e equilíbrio de fases como sobre o
seu impacto nos processos de extração e purificação e no ambiente. Ambos
são relevantes para o desenvolvimento de biorrefinarias, onde estes
compostos podem desempenhar um papel importante dada a sua ubiquidade,
valor económico e variedade de aplicações.
Esta tese está relacionada com a extração de terpenos de fontes naturais e a
sua posterior separação e purificação. Além do desenvolvimento de novos
métodos experimentais para medir propriedades termodinâmicas e equilíbrios
de fases, algumas abordagens teóricas foram também consideradas para o
mesmo fim.
Inicialmente, de forma a criar novas aplicações para estes compostos e tirando
vantagem da sua baixa solubilidade em água, tal como demonstrado por novas
e precisas determinações experimentais, os terpenos são utilizados para
preparar solventes hidrofóbicos sustentáveis e de baixo custo, no âmbito dos
solventes eutécticos profundos. Depois, com base nos coeficientes de
atividade a diluição infinita e previsões do COSMO-RS, foi feita uma seleção
de líquidos iónicos com potencial para o fracionamento de terpenos. Mais
ainda, visando o desenvolvimento de novos processos de separação de
terpenos, foram também formulados e caracterizados solventes eutécticos
profundos compostos por sais de amónio e ácidos monocarboxílicos.
Finalmente, e com o objetivo de desenvolver modelos precisos para o destino
dos terpenos no ambiente, uma série de propriedades físico-químicas
essenciais foi medida e modelada.<br>Terpenes belong to what is probably the largest and most diverse class of
natural products with applications in several industries due to their flavor, and
fragrance. Their high number, variety of structures and chemical complexity,
make of them a class of compounds for which there are still many studies to be
carried out and questions to be answered both concerning their thermophysical
properties and phase equilibria and their impact in their extraction and
purification processes and on their environmental impact. Both are relevant for
the development of the biorefinery where these compounds may play an
important role given their ubiquity, economic value and variety of applications.
This thesis is related to terpenes extraction from natural sources and their
subsequent separation and purification. Besides to the development of new
experimental procedures for thermodynamic properties and equilibrium
measurements, some theoretical approaches were also applied to this end.
First, to create new applications for this compounds, and taking advantage of
their very low solubility in water as shown by new and accurate experimental
determinations, terpenes are used to prepare sustainable and cheap
hydrophobic solvents within the deep eutectic solvents framework. After, based
on the activity coefficients at infinite dilution measurements and COSMO-RS
predictions a selection of ILs was made with potential for terpenes fractionation.
Yet, and aiming at the development of new separation processes of terpenes,
deep eutectic solvents composed of ammonium salts and monocarboxylic
acids were also formulated and characterized. Finally, and targeting the
development of accurate models for the fate of terpenes in the environment, a
range of essential physicochemical properties of terpenes were measured and
modelled.
21
Sumonsiri, Nutsuda. "Effect of Powder and Target Properties on Food Powder Coating and Comparison of Solid-liquid Separation (SLS) and Vacuum Concentration of Tomato Juice." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1336625577.
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Cruz, Othon Carlos da [UNESP]. "Desempenho de um hidrociclione de geometria rietema como pré filtro para sistemas de irrigação." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/105302.
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cruz_oc_dr_jabo.pdf: 582231 bytes, checksum: 0d0f21ba758e5ca444fec02d67a3b555 (MD5)<br>Funep<br>Os hidrociclones são equipamentos amplamente utilizados pela indústria em processos envolvendo separação sólido-líquido, porém, ainda, pouco divulgados na agricultura irrigada brasileira. Buscou-se neste trabalho determinar a perda de carga e avaliar o desempenho de um hidrociclone de geometria “Rietema” como pré-filtro de partículas sólidas. Os testes foram realizados no Centro Federal de Educação Tecnológica de Uberaba - MG - Brasil utilizando um hidrociclone de geometria “Rietema”. Este equipamento possui um diâmetro de 19,20 cm na parte cilíndrica e opera com vazões variando entre 10 m3 h-1 e 27 m3 h-1. Os materiais particulados usados em suspensão foram: solo franco-argiloso e areia de rio. Os resultados mostraram que a perda de carga máxima média foi de 52 kPa e 47 kPa para as suspensões aquosas de areia e solo, respectivamente. Seu melhor desempenho ocorreu operando com suspensão aquosa de areia, apresentando eficiência total de 92,31% para a vazão de 26,97 m3 h-1. Dentre as conclusões pode-se inferir que o equipamento avaliado é eficiente para remoção de partículas de areia, podendo ser utilizado como pré-filtro em sistemas de irrigação.<br>The hydrocyclones are equipments widely used by industry in cases involving solid-liquid separation, but still, little reported in brazilian irrigated agriculture. The proposal of this research was to determining the head loss and evaluate the performance of a hydrocyclone of geometry “Rietema” as a pre-filter of solid particles. The tests were performed in the Centro Federal de Educação Tenológica de Uberaba - MG - Brazil using a hydrocyclone of Rietema geometry. This equipment has a diameter of 19.20 cm at the cylindrical part and operates with flows ranging between 10 m3 h-1 and 27 m3 h-1. The materials used in particulate suspension were: clay loam soil and sand from river. The results showed that the average maximum head loss was 52 kPa and 47 kPa of aqueous suspensions of sand and soil, respectively. Its best performance occurred operating with slurry of sand, presenting total efficiency of 92.31% for flow rate of 26.97 m3 h-1. Among the conclusions can be inferred that the equipment is judged effective at removing particles of sand and can be used as pre-filter in irrigation systems.
23
Manfoumbi, Christian. "Précipitation des gels de silice en solution aqueuse sursaturée à forte acidité : mécanismes et mésostructures, application à la filtrabilité des pulpes dans les procédés hydrométallurgiques." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30251/document.
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La formation de gels de silice dans les procédés hydrométallurgiques est très souvent problématique pour la performance des étapes de séparation solide-liquide, en raison du colmatage des filtres. Ces étapes interviennent en aval des étapes de lixiviation visant à mettre en solution les éléments d'intérêts, notamment dans des milieux à forte acidité. Egalement mis en solution au cours de ces attaques acides, le silicium précipite alors sous forme d'oxyde de silicium et forme des gels extrêmement préjudiciables à la filtration. Dans le cadre d'une collaboration avec ERAMET Research, centre de recherche d'ERAMET, groupe minier français qui conçoit des procédés hydrométallurgiques, nous avons étudié l'influence des conditions de lixiviation d'un minerai spécifique sur la cinétique de dissolution du silicium ainsi que sur les mécanismes de précipitation de la silice en milieu acide. Nous avons montré qu'en-dessous d'une valeur de pH égale à 2, la silice polymérise pour former des gels suivant des mécanismes indépendants de la composition ionique de la solution. L'étude structurale des gels obtenus, réalisée par diffusion de rayonnement aux petits angles (SAXS) nous a conduit à proposer un modèle pour la mésostructure qui permet de comprendre leur impact sur les vitesses de filtration. Par la suite, des stratégies consistant à modifier la mésostructure des gels par des approches physiques ou physico-chimiques ont été considérées. Les résultats obtenus ont montré la possibilité d'utiliser à court terme ces stratégies pour améliorer la filtrabilité des gels de silice dans un procédé hydrométallurgique<br>The formation of silica gels in hydrometallurgical processes is very often problematic for the performance of the solid-liquid separation steps, due to clogging of the filters. These steps are carried out downstream of leaching aiming to solubilize the elements of interests, in particular in solutions with strong acidity. Also dissolved during acidic leaching, the silicon then precipitates in the form of silicon oxide and forms gels extremely detrimental to filtration. In collaboration with ERAMET Research, a research center of ERAMET, a french mining group that designs hydrometallurgical processes, we studied the influence of the leaching conditions of a specific ore on the dissolution kinetics of silicon as well as on the mechanisms of precipitation of silica in an acidic solution. We have shown that below a pH value of 2, silica polymerizes to form gels following mechanisms independent of the ionic composition of the solution. Based, on the structural study of the gels, carried out by small angle radiation scattering (SAXS) we proposed a model for the mesotructure, which explain the impact on filtration rates. Subsequently, strategies to modify the mesostructure of the gels by physical or physicochemical approaches were considered. The results have shown the potentialities of these strategies in the short term to improve the filterability of precipitated silica gels in a hydrométallurgical process
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Beydoun, Donia Chemical Engineering & Industrial Chemistry UNSW. "Development of a novel magnetic photocatalyst : preparation, characterisation and implication for organic degradation in aqueous systems." Awarded by:University of New South Wales. Chemical Engineering and Industrial Chemistry, 2000. http://handle.unsw.edu.au/1959.4/20451.
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Magnetic photocatalysts were synthesised by coating a magnetic core with a layer of photoactive titanium dioxide. This magnetic photocatalyst is for use in slurry-type reactors in which the catalyst can be easily recovered by the application of an external magnetic field. The first attempt at producing this magnetic photocatalyst involved the direct deposition of titanium dioxide onto the surface of magnetic iron oxide particles. The photoactivity of these Fe3O4/TiO2 was lower than that of single-phase TiO2 and was found to decrease with an increase in the heat treatment. These observations were explained in terms of an unfavourable heterojunction between the titanium dioxide and the iron oxide core. Fe ion diffusion from the iron oxide core into the titanium dioxide matrix upon heat treatment, leading to a highly doped TiO2 lattice, was also contributing to the observed low activities of these samples. These Fe3O4/TiO2 particles were found to be unstable, with photodissolution of the iron oxide phase being encountered. This photodissolution was dependent on the heat treatment applied, the greater the extent of the heat treatment, the lower the incidence of photodissolution. This was explained in terms of the stability of the iron oxide phases present, as well as the lower photoactivity of the titanium dioxide matrix. In fact, the observed photodissolution was found to be induced-photodissolution. That is, the photogenerated electrons in the titanium dioxide phase were being injected into the lower lying conduction band of the iron oxide core, leading to its reduction and then dissolution. Thus, the approach of directly depositing TiO2 onto the surface of a magnetic iron oxide core proved ineffective in producing a stable magnetic photocatalyst. The introduction of an intermediate passive SiO2 layer between the titanium dioxide phase and the iron oxide phase inhibited the direct electrical contact and hence prevented the photodissolution of the iron oxide phase. Improvements in the photoactivity were seen to be due to the inhibition of both the electronic and chemical interactions between the iron oxide and titanium dioxide phases. Preliminary optimisation experiments revealed that a thin SiO2 layer is sufficient for inhibiting the photodissolution. The thickness of the TiO2 coating was found not to have a significant effect on the photocatalytic performance of the coated particles. Finally, heat treating for 20 minutes at 450??C was sufficient for converting the titanium dioxide into a photoactive phase, longer heating times had no beneficial effect on the photoactivity.
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Lawson, Kathryn Elizabeth. "Removal of Water-Extractable Phosphorus from Dairy Manure." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500610175015237.
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Macedo, Sofia Alexandra de Negrier Almeida. "Avaliação do impacto ambiental de novas estratégias de gestão de chorumes para minimização de perdas de nutrientes e aumento da produção." Master's thesis, ISA, 2013. http://hdl.handle.net/10400.5/6466.
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Mestrado em Engenharia do Ambiente - Gestão Ambiental - Instituto Superior de Agronomia<br>The increasing of population along with the decrease of agricultural area led to the intensification of agriculture and livestock production in order to continue to respond to the current food requirements. Consequently there has been an increase of animal waste that might be a source of environmental pollution.
This study has as main objective to evaluate strategies for land application of slurry in relation to its environmental impact and the agronomic value of slurry. The following treatments were considered: acidification, solid-liquid separation and the impact of slurry incorporation shortly after its surface application.
An assay in pots has been performed during which emissions of ammonia (NH3) and greenhouse gases (GHG) were monitored and also the concentration of nutrients in the soil solution. At the end of the assay, the production of fodder oats was evaluated as well as the export of nutrients associated.
It has been concluded that the best combination of treatments is the surface application of acidified slurry without incorporation. As the method currently recommended is the injection of slurry, that has several limitations, it may be relevant to review the legislation concerning land application of livestock effluents, if future assays to full scale validate our results.
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Martins, Jason Alves. "Separador solido-liquido para operação em fundo de poços de petroleo." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264088.
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Orientador: Eugenio Spano Rosa<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica<br>Made available in DSpace on 2018-08-07T21:12:52Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006<br>Resumo: O presente trabalho investiga os mecanismos de separação sólido-líquido em separadores tubo-ciclônicos. O trabalho é desenvolvido a partir de testes experimentais e simulação numérica. A etapa experimental investiga a influência do aumento de viscosidade sobre a eficiência do separador. Através de uma análise dimensional, os dados experimentais são reduzidos em grupos adimensionais. Obtem-se uma correlação entre a eficiência de separação e os grupos adimensionais. Ela revela como a eficiência depende dos parâmetros geométricos e operacionais do separador. A correlação obtida possibilita dimensionar estes separadores para cenários com elevada viscosidade. As simulações numéricas são realizadas utilizando um método de volumes finitos. O processo de separação é estudado através do adimensional Stokes. São introduzidos os conceitos de superfície de captura e tempo de residência de partículas. Define -se um importante parâmetro do escoamento, o comprimento de decaimento. Propõe-se um modelo unidimensional para o separador. Realiza-se com base neste modelo uma análise comparativa entre dois separadores. Os resultados são coerentes com dados experimentais e indicam quais características geométricas melhoram a eficiência do separador<br>Abstract: This work investigates the solid-liquid separation mechanisms in swirl tubes through experimental and numerical analysis. In the experimental phase, it is analyzed the impact of the viscosity increase on the separation efficiency of swirl tubes. The experimental data are reduced using dimensional analysis. A functional relationship between the separation efficiency and the dimensionless groups is obtained, allowing to calculate the separation efficiency dependency on the liquid viscosity, flow rate, particle size, and other geometrical parameters of the separator. This relationship helps to design these desander devices to scenarios with high viscosity. Numerical simulations are carried out in a structured grid using a finite volume method. Separation process is studied through the Stokes number. The concepts of capture surface and residence time of particles are introduced and an important flow field parameter, the length of decay is defined. A one-dimensional model is proposed for the swirl tube. A comparative analysis between two separators is done based on the one-dimensional model. The results are in agreement with experimental data and indicate which geometrical features help to improve the separator efficiency<br>Mestrado<br>Termica e Fluidos<br>Mestre em Engenharia Mecânica
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Pillin, Béatrice. "Utilisation des champs magnétiques intenses pour la séparation d'inclusions : application aux particules solides immergées dans les métaux liquides." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0017.
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La separation de particules solides immergees dans un liquide en ecoulement au travers d'un champ magnetique statique intense a ete etudiee. Des forces magnetiques, liees aux susceptibilites magnetiques et au gradient spatial de champ magnetique, ou bien des forces electromagnetiques, liees aux conductivites electriques et au mouvement relatif de l'element conducteur par rapport au champ magnetique, peuvent etre mises en oeuvre. La separation est effective lorsque ces forces agissent sur la trajectoire des particules perpendiculairement a la direction de l'ecoulement. Ce sont les forces precedemment citees agissant soit directement sur la particule, soit via le liquide par l'intermediaire de forces de pression. A partir de la distribution du champ magnetique delivre par un bobinage supraconducteur axisymetrique vertical, deux principes de separation sont proposes. Un exploite les zones de gradient de champ ou un ecoulement de liquide conducteur et/ou magnetique, de type cylindrique parallele a l'axe du bobinage permet d'obtenir des forces electromagnetiques et magnetiques. L'autre exploite la zone centrale de champ homogene ou un ecoulement de type conique convergent ou divergent, incline par rapport a l'axe du bobinage, permet d'obtenir des forces electromagnetiques. Les effets des forces electromagnetiques et magnetiques sur la deviation de particules sont demontres experimentalement grace a la conception et l'exploitation de dispositifs creant des ecoulements cylindrique ou conique dans les differentes zones de champ de bobinages supraconducteurs. Des solutions aqueuses a proprietes conductrices et/ou magnetiques chargees en particules de plexiglas sont testees. Une simulation numerique des aspects electromagnetiques induits dans le procede est developpee et validee a partir des ordres de grandeur deduits de l'approche theorique ou obtenus experimentalement.
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Smaniotto, André Luiz Amorim. "Aplicação de sedimentadores de fluxo vertical na separação sólido-líquido de água de processo em usinas de beneficiamento de carvão mineral na região sul de Santa Catarina." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/170967.
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O processo de espessamento e clarificação dos efluentes das usinas de beneficiamento de carvão mineral com a adoção de sedimentadores é uma prática consagrada ao longo de todo o mundo uma vez que é necessário o reaproveitamento da água utilizada tanto por questões econômicas como ambientais. O primeiro sedimentador, tipo espessador, a entrar em operação industrial na região carbonífera de Santa Catarina foi instalado na Mina Barro Branco da Carbonífera Rio Deserto em 2007. O equipamento era dotado de lamelas de PVC e foi instalado como alternativa às bacias de decantação, que apresentam alto custo de construção e operação. Contudo, o equipamento se mostrou ineficaz devido a deposição de sólidos nas lamelas. Essa dificuldade levou a adoção de outros modelos de sedimentadores de fluxo vertical que não utilizam lamelas. Esse trabalho apresenta os dados disponíveis da operação do equipamento com as lamelas na Mina Barro Branco e resultados atuais da operação dos sedimentadores da Mina Esperança sem lamelas. Nesse segundo caso foi medida a vazão, concentração de sólidos e dos metais ferro, alumínio e manganês, nos fluxos de entrada e saída. No efluente clarificado mediu-se ainda o pH e a turbidez. Registraram-se dados de uma operação satisfatória, com impacto importante na redução dos custos no transporte e deposição dos rejeitos finos e no tratamento do overflow clarificado possibilitando o descarte de acordo com a Legislação Ambiental.<br>The process of thickening and clarifying the effluents of mineral coal processing plants with the use of settlers is a well-established practice throughout the world since it is necessary to reuse the water used for both economic and environmental reasons. The first settler, a thickener type, to enter into industrial operation in the Santa Catarina coal region was installed at the Barro Branco Mine of the Carbonifera Rio Deserto in 2007. The equipment was equipped with PVC lamellae and was installed as an alternative to the decantation basins, which have a high cost of construction and operation. However, the equipment proved to be ineffective due to deposition of solids in the lamellae. This difficulty led to the adoption of other models of vertical flow settlers that do not use lamellae. This work presents the available data of the operation of the equipment with lamellae in the Mina Barro Branco and current results of the operation of the settlers in the Mina Esperança without lamellae. In this second case the flow, concentration of solids and iron, aluminum and manganese metals in the inflow and outflow were measured. In the clarified effluent the pH and turbidity were also measured. Data were recorded for a satisfactory operation, with a significant impact on the reduction of costs in the transportation and deposition of the fine tailings and in the treatment of the clarified overflow, allowing the disposal according to the Environmental Legislation.
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Akhiar, Afifi. "Caractérisation de la fraction liquide des digestats issus de la codigestion de résidus solides." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS004/document.
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Le secteur de la méthanisation à la ferme ou territoriale connait un fort développement, entrainant la production de grandes quantités de digestats. Si la fraction solide de ces digestats est généralement utilisée en tant qu’amendement organique, la fraction liquide peut être valorisée par la récupération des éléments minéraux bien que la présence de composés organiques pose des problèmes de traitement et d’élimination. Les objectifs de cette thèse sont i) de caractériser la fraction liquide des digestats et donner des premiers éléments pour leur futur traitement et ii) d’expliquer la variabilité des composés résiduels présents dans cette fraction liquide en relation avec l’origine des substrats, les paramètres du procédé de méthanisation et le type de séparation solide/liquide. Dans une première partie, nous avons caractérisé de manière détaillée onze digestats issus d’installations industrielles de co-digestion. Le fractionnement par neuf filtrations successives de la fraction liquide des digestats a permis de quantifier la contribution des matières en suspension, des colloïdes grossiers et fins et des matières dissoutes aux différents paramètres physico-chimiques et biologiques. Il a été montré la faible biodégradabilité aérobie des composés organiques dont la majeure partie se trouve dans la matière en suspension (> 1,2 µm). Pour élargir la base de données, nous avons caractérisé dix-huit digestats supplémentaires et un digestat de boues de station d’épuration dont les fractions liquides ont été fractionnées par deux filtrations successives (1,2 μm et 1 kDa). L’analyse en composantes principales, la classification hiérarchique et la matrice de corrélation réalisées sur l’ensemble des 30 digestats ont mis en avant l’impact majeur des techniques de séparation solide/liquide sur la composition de la fraction liquide des digestats. Dans le groupe des techniques de séparation hautement performantes, des sous-groupes ont permis de distinguer les digestats à base de boues d’épuration, ceux à base de lisiers porcins et ceux issus de procédés piston thermophiles. Dans le groupe des procédés de séparation à faible performance, les teneurs en DCO et matières sèches de la fraction liquide des digestats ont été corrélées aux teneurs en cultures énergétiques et fumiers bovins dans l’alimentation. Finalement, pour l’ensemble des digestats, le paramètre SUVA, lié à la teneur en matière aromatique et à la stabilisation des composés, a été corrélé au temps de séjour des digesteurs. Pour comprendre l’origine des composés résiduels observés dans la fraction liquide des digestats issus de la co-digestion avec de fortes proportions de fumier bovin, quatre réacteurs CSTR alimentés avec respectivement de la paille de blé, de la bouse de vache et du fumier ont été conduits pendant 48 semaines. Les performances de méthanisation ont mis en évidence le caractère âgé du fumier qui avait été partiellement dégradé pendant le stockage à la ferme. Ainsi la fraction liquide du digestat du fumier a présenté les plus fortes concentrations en composés organiques qui en outre présentaient une complexité, mesurée par fluorimétrie 3D, plus élevée que les autres substrats. La fraction liquide du digestat issue de la méthanisation de la paille a révélé les plus fortes proportions de DCO dans les fractions colloïdales et dissoutes. La faible biodégradabilité des composés organiques et leur forte proportion dans les matières en suspension suggèrent le développement de procédés physico-chimiques de séparation tels que la coagulation pour le traitement de la fraction liquide des digestats<br>Agricultural and centralized biogas plants are facing a fast development, leading to the production of huge amounts of digestates. Whereas the solid fraction of digestates is used as fertilizer, the liquid fraction can be valorized by the recovery of mineral materials, although the presence of organic compounds may be problematic for the treatment and disposal of this effluent. The objectives of this thesis are: i) to characterize the liquid fraction of digestates and to provide guidelines for its further treatment, ii) to explain the variability of residual compounds in the liquid fraction of digestates in relation with substrate origin, process parameters and the type of solid-liquid separation. In a first part, eleven digestates from full scale codigestion plants were thoroughly characterized. Their liquid fractions were fractionated by nine successive filtrations, which allowed quantifying the contribution of suspended particles, coarse and fine colloids and dissolved matter on several physico-chemical and biological parameters. Organic compounds were mainly found in suspended particles (> 1.2 µm) and presented low aerobic biodegradability. To enlarge the data base, eighteen more digestates from codigestion and one digestate from waste activated sludge were characterized; their liquid fractions were fractionated by two successive filtrations (1.2 μm and 1 kDa). Principal component analysis, hierarchical clustering analysis and correlation matrix carried out on the 30 digestates set, highlighted the major impact of the solid-liquid separation process on the composition of the liquid fraction of digestates. In the high performance separation process group, subgroups allowed separating digestates from sewage sludge, digestates from pig manure and digestates from plug-flow thermophilic processes. In the low performance separation process group, COD and total solids concentration in the liquid fraction of digestates were correlated to the percentage of energy crops and cow manure in the feed. Finally, SUVA parameter which accounts for aromatic compounds content and the stabilization of organic matter, was correlated to the retention time in digester for the whole digestates set. To understand the origin of residual compounds in the liquid fraction of digestates from co-digestion of high proportions of cattle manure, four CSTR reactors fed with wheat straw, cow dung and cow manure were operated for 48 weeks. Anaerobic digestion performances showed that cow manure had undergone some aerobic degradation during its storage at the farm. Therefore, the liquid fraction of manure digestate had the highest concentrations in organic compounds. In addition, these organic compounds had the highest complexity measured by 3D fluorimetry. The low biodegradability of organic compounds and their high percentage in suspended particles suggest the development of physico-chemical separation process such as coagulation for the treatment of the liquid fraction of digestates
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Orsine, Noeber Maciel. "Definição de tecnologias para desaguamento de ultrafinos ricos de minério de ferro : uma aplicação na Vale Carajás - Pará - Brasil." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/140518.
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O minério de ferro produzido no complexo de Carajás traz consigo características mineralógicas que conferem um elevadíssimo teor de Fe em todas as suas frações granulométricas. Dessa forma, ao final da cadeia produtiva, tanto os produtos comerciais mais grosseiros quanto os finos contem cerca de 62% de Fe contido na sua composição. Importante destacar que em Carajás as fases no processamento desse minério são apenas para cominuição e classificação por tamanho. Não existem etapas de concentração e os produtos são diferenciados por suas respectivas curvas granulométricas: o “granulado” - mais grosseiro (> 13 mm), o “Sinter-Feed” (< 13 mm e > 0,5 mm) e o “pellet feed” (< 0,15 mm). Garantir a correta distribuição granulométrica da matéria prima é uma premissa de mercado. A ultima etapa da classificação é feita através de hidrociclones e gera um overflow ultrafino de altíssima superfície específica maior que 6.500 Blaine e com 45% até 95 % < 7 μm. E ainda possui um elevado teor de Fe - cerca de 62 %. Dessa forma os objetivos gerais dessa pesquisa buscaram a solução para essa oportunidade de recuperar e vender esses rejeitos. O estudo sugeriu através de ensaios com tecnologias capazes de desaguar os ultrafinos gerados para 9,00 % de umidade, que é o valor que permite a movimentação e o manuseio desses rejeitos, além de permitir sua incorporação na blendagem de produtos mais grossos. Desse modo, foram realizados experimentos em diversos laboratórios externos e em escala piloto na Usina de Carajás com amostras dos dois rejeitos ultrafinos das duas fases de hidrociclonagem: o natural e o moído. Ficou evidente que o equipamento tem de combinar necessariamente e de forma eficiente dois fatores essências ao desaguamento: elevadíssimas pressões e altas temperatura na operação desses ultrafinos. A produtividade atingida foi da ordem de 50 t/h x m² para o rejeito da hidrociclonagem do Sinter Feed e 40 t/h x m² para o rejeito dos hidrociclones da Moagem.<br>The Iron ore that is produced in Carajás mining complex brings mineralogical characteristics that give a very high Fe content in all its size fractions. Thus, at the end of the production chain both coarser and fine contains about 62% Fe contained in its composition. Importantly, in Carajás stages in the processing of this ore are for reduction and classification by size. There is thus no concentration steps and products are differentiated by their respective size distribution curves: the "grain" - coarser (> 13 mm), the "Sinter-Feed" (<13 mm and > 0.5 mm) and the "pellet feed" (<0.15 mm). Ensure proper particle size distribution of the raw material is a market premise. The last step of classification is made using hydrocyclones and generates an overflow ultrafine high specific surface area greater than 6.500 Blaine and with 45% to 95% <7 μm. And has a high Fe content - about 62%. The overall objectives of this research sought the solution to this opportunity to recover and sell these “tailings”. The study suggested by testing with technologies capable of flowing into the ultrathin generated to 9.00% of moisture, which is the value that allows movement and handling these wastes, and allows their incorporation into the blending of thicker products. Thus, experiments were carried out in several external laboratories and pilot-scale plant in the Carajás with samples of both ultrafine “tailings” of the two phases of hydrocycloning: the natural and the ground. It was evident that the equipment must necessarily match and two efficiently factors essences to dewatering: very high pressure and high temperature operation of these “tailings”. The productivity achieved was around 50 t/h x m² in reject of the Sinter Feed hydrocycloning and 40 t/h x m² to reject of the grinding hydrocyclones.
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Balci, Oguz. "Affinity chromatographic purification of recombinant human growth hormone." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12609269/index.pdf.
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The purpose of the study is to purify human growth hormone from the fermentation broth by affinity chromatography. For this purpose, human growth hormone specific oligonucleotide aptamers are selected among an aptamer library<br>selected oligonucleotides were synthesized and used as ligands. Effect of pH on ligand-human growth hormone complex formation was investigated and the highest complex formation was obtained at pH= 7.0. Human growth hormone is separated from the fermentation broth with 99.8% purity and 41% overall yield. The equilibrium data obtained was described by Langmuir type isotherm where saturation constant (q0) and affinity constant (K) are calculated as 0.338 mg hGH/µ<br>mol aptamer and 0.059 mg hGH/ml, respectively. Further, equilibrium data obtained using aptamer affinity column was described by Langmuir type isotherm where saturation constant (q0) and affinity constant (K) are 0.027 mg hGH/µ<br>mol aptamer and 1.543 mg hGH/ml, respectively. It is possible that, selected aptamer can be used for purification of bulk amounts of recombinant human growth hormone by using aptamer affinity chromatography.
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Wei, Shuting. "Capturing molecules with templated materials analysis and rational design of molecularly imprinted polymers /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/24817.
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Thesis (Ph.D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2008.<br>Committee Chair: Boris Mizaikoff; Committee Member: Andrew Lyon; Committee Member: Ching-Hua Huang; Committee Member: David Collard; Committee Member: Facundo M. Fernandez.
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Jean-Baptiste, Conrardy. "Contribution à l’étude de l’électro-compression des boues résiduaires urbaines." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3037/document.
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Dans une problématique de réduction des volumes de déchet, l’électro-compression (ou électro-déshydratation) apparaît être une technique efficace pour éliminer une grande partie de l’eau des boues résiduaires urbaines. Cette thèse de doctorat présente différentes contributions à l’étude de ce procédé appliqué à ce type de boues. Un lien entre les données cinétiques et énergétiques est établi par une étude expérimentale à l’échelle du laboratoire. D’autre part, un nouveau modèle relativement simple est proposé pour l’étude et la simulation de l’électro-compression et permet de mettre en avant les phénomènes prépondérants. Enfin, un protocole d’analyse ionique des filtrats et des tranches de gâteaux de boue a permis une étude de la migration des espèces chimiques au cours de l’électro-déshydratation<br>In the purpose to reduce waste amount, the electro-dewatering process is a promising technique to efficiently withdraw a large part of the water included in wastewater sludge. This PhD thesis contributes in various ways to the study of this technique. Lab-scale experiments showed correlations between dewatering kinetics and energy consumption of the process. Moreover, a new model, relatively simple, is proposed to study and simulate the process. This model highlights the main phenomena involved in the electro-dewatering. Finally, a study of the migration of chemical species during the dewatering process is carried out thanks to an analytical protocol measuring ions in filtrates and sludge slices.1
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Burešová, Jitka. "Využití separačních metod pro studium vybraných léčiv a pesticidů ve vodách." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-234424.
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This work is focused on the study of penetration of pesticides and pharmaceuticals in the aquatic environment. The aim was to develop and verify the optimal method for long-term monitoring of the occurrence of selected pesticides and pharmaceuticals in surface waters. Two frequently used analgesics ibuprofen and diclofenac, and carbamazepine that is used to treat epilepsy, were chosen from the group of drugs. A group of 41 pesticides were selected for monitoring too. The attention was focused on a group of urea pesticides and phenoxyacetic acids, as well as on selected pesticides falling to the group of priority substances or identified as environmental quality standards. Some of pesticides were selected because their consumption in the Czech Republic exceeds 30 tons a year. Liquid chromatography with tandem mass spectrometry (LC / MS / MS) was used for the determination of selected analytes in surface waters. Two optimized analytical method were developed. Ten analytes were determined in negative ion mode and 34 analytes in positive ion mode. Solid phase extraction (SPE) was used for purification and concentration of the samples. Developed methodology was validated and used for monitoring of selected compounds in samples of surface waters from the Morava River basin. Samples were collected on the rivers Morava and Svratka monthly for two years. Samples from the river Blata and stream Nivnička were collected for one year. Surface water samples were also collected from the river Litava. Four samples were taken throughout the length of the flow during one day. Smaller streams were chosen for monitoring because of the probability of occurrence of pesticides. They flow abundantly agriculturally cultivated areas. Drugs ibuprofen and diclofenac were detected in all taken samples, carbamazepine mostly. Among the most commonly occurring pesticides were bentazon, diuron, isoproturon, carbendazim, MCPA, MCPP, propiconazole, tebuconazole and 2,4-D.
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Pereira, Marina Seixas. "Caracterização de cascalho e lama de perfuração ao longo do processo de controle de sólidos em sondas de petróleo e gás." Universidade Federal de Uberlândia, 2010. https://repositorio.ufu.br/handle/123456789/15156.
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Drilling, one of the stages of oil and gas exploration, now has as targets regions of
great complexity, with high depths. Coated or contaminated cuttings with drilling fluid are a
result of drilling. The drilling fluids are water-based or non-aqueous based liquids. A more
restrictive environmental legislation and the need to reduce the costs of drilling (exploration
and production) lead to optimization of solid-liquid separation and recycling drilling fluids.
Because oil industry has to submit itself to ever more stringent environmental laws it has
applied a great deal of investments on sustainability research. In this context, this work
provides a study of the characteristics of drilling cuttings and synthetic drilling muds at
different steps of the solids control sistem, in order to know their behavior and its change over
the process. The concentration of water, organic phase and solids in the mud were measured.
The density and particle size of the cuttings were analyzed. The rheology and thixotropy of
the mud were investigated. For this, samples of drilling mud were collected throughout the
solids control system of five PETROBRAS onshore drilling rigs in Bahia (BA). The
concentrations index are so important when investigating the efficiency of operation of the
equipments in the solids control. The density of solids is very close to the density of clays.
The results show that the rheology of drilling mud in the solids control process behaves as a
non-Newtonian fluid, pseudoplastic, viscoplastic and thixotropic. The particle size of solids
varies with operating conditions and always presents two average diameters by sample. The
cutting dryer, a vertical centrifuge, plays a key role in the waste disposal due the stringent
environmental laws, especially on offshore platforms. Thus, in order to research the
optimization or restructuration of this step in the waste disposal, a study was carried on this
equipment and the main points of its structure and operation were reported.<br>A perfuração, uma das etapas da exploração de petróleo e gás, hoje objetiva cenários
geológicos de grande complexidade, com elevadas profundidades. Como efluente da atividade
exploratória há a geração de cascalhos contaminados ou revestidos com fluido de perfuração.
Uma legislação ambiental mais rigorosa e a necessidade de reduzir os custos de perfuração
(prospecção e produção) apontam para a necessidade de otimização da separação e reciclagem
do fluido de perfuração de poços de petróleo e gás. A atividade petrolífera é desenvolvida em
condições cada vez mais restritivas do ponto de vista ambiental, sendo incessantes os estudos
e investimentos em busca da sustentabilidade. Como exemplos de equipamentos para o
processamento da lama de perfuração podem ser citados as peneiras vibratórias, os
hidrociclones e as centrífugas. Neste contexto, o presente trabalho traz um estudo detalhado
das características dos sólidos e da lama de perfuração base n-parafina em diferentes
pontos do processo de controle de sólidos, com o objetivo de investigar o comportamento dos
mesmos e sua alteração ao longo do processo. Foram realizadas análises de concentração de
água, fase orgânica e sólidos na lama, densidade dos sólidos, reologia e tixotropia da lama e
granulometria dos sólidos. Para isso, amostras de lama de perfuração foram coletadas ao
longo do sistema de controle de sólidos em cinco sondas de perfuração terrestre da Petrobras
no interior da Bahia (BA). As concentrações analisadas são de grande importância na
investigação da eficiência de operação dos equipamentos do processo de controle de sólidos.
A massa específica dos sólidos é bem próxima da massa específica de argilas. Os resultados
de reologia mostram que a lama de perfuração em todo o processo de controle de sólidos se
comporta como um fluido não-newtoniano, pseudoplástico, viscoplástico e tixotrópico. A
granulometria dos sólidos varia com as condições de operação e apresenta, no geral, dois
diâmetros médios em cada corrente amostrada. O secador de cascalho, um tipo de centrífuga
vertical, desempenha papel fundamental na adequação dos resíduos às leis ambientais de
descarte, principalmente em plataformas offshore. Assim, visando futuramente a otimização
ou mesmo reestruturação desta etapa do processo de descarte de resíduos, foi realizado um
estudo sobre esse equipamento e levantado os pontos principais de sua estrutura e operação.<br>Mestre em Engenharia Química
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Hassen, Barkai Allatchi. "Caractérisation d’un écoulement diphasique dans un airlift sous dépression. Application pour l’extraction des matières solides en suspension." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI038.
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Les colonnes à bulles sont des contacteurs gaz-liquide très répandus en milieu industriel, notamment dans des applications de procédés chimiques, biologiques et minéralogiques. Dans la gamme de colonne à bulles disponible, l'airlift sous dépression est une innovation française présentant des caractéristiques très intéressantes pour le pompage hydraulique, le transfert de masse et la séparation des matières en suspension. Ce travail de thèse s'inscrit dans le cadre du développement de cet airlift amélioré, très utilisé dans le milieu industriel. L'objectif de la thèse est la caractérisation hydrodynamique de la colonne airlift sous dépression et l'analyse de ses capacités à assurer la fonction de séparation solide-liquide pour des particules en suspension. Le travail est exclusivement expérimental et le dispositif expérimental est constitué d'une colonne à bulles verticale transparente en plexiglass soumise à une dépression en tête et connectée à un bassin de recirculation hydraulique. L'analyse hydrodynamique a été réalisée à l'aide de capteur de pression différentielle pour l'étude globale et à l'aide d'une double sonde optique pour une caractérisation locale. Les résultats obtenus ont permis d'étudier le régime d'écoulement pour les principaux paramètres : le taux de vide, la vitesse d'ascension et le diamètre des bulles. La Vélocimétrie par Images des Particules a été appliquée pour visualiser et analyser les structures d'écoulement dans le bassin de recirculation. Les capacités extractives de la colonne ont été étudiées en eau douce avec ajout de produits tensioactifs. La caséine soluble et le Methyl Iso Butyl Carbinol (MIBC) sont les deux tensioactifs qui ont donné les meilleurs résultats en termes de séparation solide-liquide des matières en suspension. Ce travail a contribué à la compréhension de l'hydrodynamique des airlift sous dépression et a permis de mettre en évidence les potentialités de cette colonne dans le processus de séparation solide-liquide. Le travail ouvre aussi la voie à la modélisation numérique de l'hydrodynamique de la colonne en s'appuyant sur les résultats expérimentaux<br>Bubble columns are gas-liquid contactors widely used in industry, especially in chemical, biological and mineralogical process applications. In the range of bubble columns available, the vacuum airlift is a French innovation with very interesting characteristics for hydraulic pumping, mass transfer and suspended matter separation. This thesis work is part of the development of this improved airlift, which is widely used in the industrial environment. The objective of the thesis is the hydrodynamic characterization of the airlift column under vacuum and analysis of its capacities to ensure the solid-liquid separation function. This work is exclusively experimental and the experimental setup is a vertical bubble column in plexiglass under vacuum and connected to a recirculation basin. The hydrodynamic analysis was carried out using a differential pressure sensor for the global study and using a double optical probe for local characterization. Results obtained made it possible to study flow regime. The main parameters obtained are the void fraction, superficial velocity and bubbles diameter. Particle Image Velocimetry is applied to visualize and analyze the flow structures in the recirculation basin. The extracting capacities of the column were studied in tap water with the addition of surfactants. Soluble casein and Methyl Iso Butyl Carbinol (MIBC) are the two surfactants that have given the best results in terms of solid-liquid separation of suspended matter. This work contributed to the understanding hydrodynamics for vacuum airlift column and helped to highlight the potential of this column in the solid-liquid separation process. This work also opens the way to numerical modelling of airlift column hydrodynamics from experimental results
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Du, Fei [Verfasser]. "Separation of solid-liquid and liquid-liquid phases using dielectrophoresis / Fei Du." 2010. http://d-nb.info/1010641530/34.
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Tu, Ssu-Hung, and 杜思鴻. "Solid-Liquid Separation of Nonaqeous Submicron Particle Suspensions." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/rgyn48.
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碩士<br>中原大學<br>化學工程研究所<br>103<br>In this study, atmospheric plasma spray was used for making tubular aluminum oxide membranes. The membranes had porous structure in the surface and high flux for pure water permeation. Moreover, it had 95% rejection rate using average particle size 0.18 μm silica particle.
As results, average pore size of the coating layer increased as substrates with larger pore sizes were utilized. Besides, for the plasma parameters, for example plasma power, spray times, spray distance and powder feed rate, changed for discussing the pure water permeation rate, particle rejection and surface structure of the sprayed membrane. At low plasma power, particles heated insufficiently, caused melt poorly. On the other hand, at high plasma power, the temperature of the plasma plume exceeded the particles boiling point, caused particles evaporated. No matter what kind of secondary gas injected into the plasma, the plasma power was so high that particles were evaporated. The optimum plasma power was 18 kW to 21 kW. As increasing the spray times, the thickness of the coating layer increased and the average pore size decreased. The optimum spray times were 5 times to 7 times in the wet process because the pure water declination rate kept at 20%. Increasing the spray distance resulted in decreasing particle rejection rate and coating efficiency due to the affecting of the ambient atmosphere on in-flight particles. Thus, the optimum spray distance was 7 cm to 10 cm. With the powder feed rate increased, the amount of injecting aluminum oxide particles increased. Plasma could not melt the particles totally, caused poor coating efficiency. The optimum powder feed rate was 1 rpm to 3 rpm.
For the application of the membrane, nonaqeous submicron particle suspensions was used for studying the steady state flux and submicron particle rejection rate under different operating pressure and backwash times, With the pressure increased, steady state flux increased to 1 bar. After that, the denseness cake resulted in a decrease of the steady state flux. Moreover, submicron particle rejection rate increased with the pressure because of the concentration polarization phenomenon. As a result, the best operating pressure was 1 bar, which had higher steady state flux and submicron particle rejection rate. On the other hand, with the backwash times increased, the steady state flux increased because of higher amount of particles be washed from the membrane surface. But the effect on submicron particle rejection rate was not clear. The best backwash times was determined to be 5 times, which had higher steady state flux and submicron particle rejection rate.
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Bekker, M. C. "Separation of solid-liquid suspensions with acoustic energy." Thesis, 2014. http://hdl.handle.net/10210/9027.
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M.Ing.<br>Fouling of suspended solids on piping and equipment causes severe operating and maintenance problems in process, water treatment and miningrelated plants. In the SASOL environment fouling related problems are mainly experienced on equipment operating in process cooling water services. Suspended solids appear in the form of activated sludge in the cooling water system and the solid particle sizes are usually submicron in size. Conventional solid liquid separation techniques like centrifuging, sedimentation, filtration, etc. could up to this stage not be applied successfully to remove the finest solids from the process cooling water system. The possibility to separate solid liquid suspensions by means of acoustic energy was investigated. The theoretical principles of acoustic waves, especially standing waves, were studied and explained. A theoretical model indicates that separation of solid/liquid suspensions can be obtained virtually immediately after acoustic energy is applied. Theoretically the size and frequency of a tipical acoustic transducer can be calculated for a specific application. Based on theoretical calculations and findings, an experimental setup was prepared to carryout experiments on different suspensions. A control suspension made-up of water and powder, of Yttlich the particle sizes were approximately 10 pm, was prepared and exposed to a standing acoustic wave. Separation was achieved successfully. Follow-up experiments were carried out to establish the optimum conditions to which separation could be achieved. Different flow velocities were tested as well as different power inputs. The best separation was achieved with the lowest flow rate of 2.5 mils and the highest available voltage of 12 Volt. These conditions were not only used to separate a control suspension but also in a real situation where it was attempted to separate suspended solids from the cooling water system. The attempts were unsuccessful. Additional experiments were also done on ash water and cooling water blowdown which also failed. The failure of effective separation of the process cooling water suspensions is due to the extremely small sizes of the solid partides in suspension. Greater energy input than was available for this project, is required as the particle sizes decreases. Provision needs to be made for all particle sizes to achieve effective results. The separation of solid liquid suspensions is achievable with the aid of acoustic energy. The physical properties of the suspension however determines the size and magnitude of the separating equipment. A proposal for the implementation of a full scale acoustic separation system is given. The proposal comprises of a parallel system to ensure continuity of the cooling process.
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Stickland, Anthony D. "Solid-liquid separation in the water and wastewater industries." 2005. http://repository.unimelb.edu.au/10187/6752.
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Water and wastewater treatment produce sludge that is dewatered prior to disposal in order to reduce disposal costs. This work combined mathematical modelling of thickeners, filters and centrifuges with accurate measurement of sludge dewatering properties to give improvements in operation, design and control of such devices, including increased throughput and reduced water content.<br>The theoretical basis of this work was the phenomenological solid-liquid separation theory of Buscall and White, 1987, in which the local volume fraction dependent properties of compressive yield stress, Py(φ), and hindered settling function, R(φ) (which, when combined, give the solids diffusivity, D(φ)), describe the material behaviour in compression. The local conservation equations were given in vector notation, converted to one-dimension, and applied to piston-driven filtration. A range of models of plate-and-frame filter presses and solid-bowl centrifuges were developed. Simple visual basic programs were written to provide operators and designers access to filter model predictions.<br>Filtration and settling tests were used to measure the material characteristics for water and wastewater treatment sludges from a range of industrial sites, including different coagulants and coagulation conditions, with weekly and seasonal variations. The results showed that ferric-based water treatment sludges have very little variability, while alum sludges can exhibit some changes in properties. New qualitative and quantitative methods were developed for wastewater sludges, which exhibit atypical filtration behaviour. The production of synthetic sewage sludge showed that this is caused by the extracellular polymeric constituent.<br>The material characteristics were used to predict the throughput and cake solids for filter presses, centrifuges and continuous thickeners. The filter models were validated at a range of water treatment plants, and used to investigate the optimisation and control of press performance. A modified-Darcy’s law, which was validated using model predictions, was used to determine the membrane resistance from on-site measurements.<br>The centrifuge models included one-dimensional transient and continuous, and two-dimensional continuous decanting models. Algorithms for the solution of the one-dimensional models were developed for both the un-networked and networked cases, and the results for a simple example illustrated. The development of the decanting centrifuge model included conversion of the conservation equations to helical coordinates, consideration of the viscous flow of the centrate down the spiral formed by the blades of the scroll, the movement of the solids due to differential speed of the scroll and the sedimentation-consolidation of the solids due to the centrifugal acceleration.<br>Civil engineering consolidation theory and testing methods were outlined and compared to filtration. The relevant dewatering parameters were related via a simple equation. The material characteristics of a kaolin sample were measured using oedometer and pressure filtration testing and compared using the derived relationship.<br>Overall, this represents several important developments in the understanding of water and wastewater sludge dewatering, especially the measurement of water treatment sludge characteristics at a range of sites and with seasonal variations, the development of analysis techniques to determine wastewater sludge characteristics, and the development or adaptation of new or existing models of filters, centrifuges and thickeners. Considerable cost savings were made possible by understanding both the material behaviour and the dewatering device.
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曹, 達啓, and Daqi CAO. "STUDIES ON SOLID-LIQUID SEPARATION OF O/W EMULSION." Thesis, 2014. http://hdl.handle.net/2237/20654.
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Chu, Yu-Hsin, and 朱育欣. "Study of Solid-Liquid Separation in Hydrocyclones for Biomass Raw Materials." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/32068350364204190539.
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碩士<br>逢甲大學<br>化學工程學所<br>98<br>Solid-liquid separation in hydrocyclones for cassava starch, modified starch and condensed molasses fermentation solubles ( C.M.S. ) were carried out by three modes which are batch, recycle loop and hydrocyclones in series, respectively. The operating parameters were feed flow rate, feed solid concentrations and fluid viscosities.
It was found that recycle loop mode was the best method of three operating modes for starch-water separation. Total operating time was shorter than free settling that about 12~15 minute instead of 6 to 8 hours for the washing or dewatering processes of modified starch. The solid recovery was about 92% or even higher, that means still has 5-8% solid loss within the total washing process.
It was also found that C.M.S. can not be clarify by small hydrocyclone, and only mild changes in COD concentrations and total sugar concentrations for the treatment of C.M.S.
After the treatment of C.M.S., the acceleration of aggregation and settlement were found. The settling velocities were varied from 0.08 to 0.19 cm/hr after treatment, which faster than free settling of 0.02 cm/hr, the total settling time of after hydrocyclone treatment was 36 hours that up to 20 times shorter than free settling. Finally, these results of solid-liquid separation in this study for decreasing settling time and increasing capacity of dewatering the starch and/or modified starch is satisfactory.
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Agomoh, Ikechukwu Vincent. "Chemically enhanced gravitational solid-liquid separation for the management of phosphorus in liquid swine manure." 2012. http://hdl.handle.net/1993/8847.
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This laboratory column (125 cm high, 15 cm diameter) research investigated solids and P removal from liquid swine manure amended with calcium carbonate, magnesium sulphate, alum and polyacrylamide (PAM). Results showed that PAM was the most effective amendment for enhancing solids removal from manure containing 1% initial total solids (TS). The effectiveness of PAM was lower at 5% and 8% than at 1% due to resuspension of solids occurring at settling times beyond 4 h. After 24 h of settling, P removal from non-amended manure was comparable to that in amended manure and decreased with TS concentration for all amendments except alum, which was equally effective at all TS concentrations. These results indicate that, for manure containing 1% TS, P can be adequately removed by gravity separation without addition of chemical amendments while alum is a more effective amendment for removing P from manure containing higher (5% and 8%) TS.
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Cheng, Chang-Yuan, and 程長遠. "Molecular Modeling of Polymers Adsorbed onto Solid Surface and Separation Mechanisms in Liquid Chromatography." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/52847304065192384605.
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博士<br>淡江大學<br>化學學系<br>87<br>The subject of dissertation is base on a molecular modeling developed to study polymers adsorbed onto solid surfaces and the separation mechanisms in liquid chromatography. The method for theoretical calculation and molecular modeling simulation is certainly favorable in studying the principles and reasons of the adsorption phenomenon with the micromolecular view.
The simulations are executed by using Cerius2 molecular modeling software. The procedure employs molecular mechanics and molecular dynamic techniques on the real time simulation on four models: (1) polymers/alumina surface model, (2) polyphenyl linkages/alumina surface, (3) polymers/solvent/silica surface and (4) components/solvents/silica gel. A set of parameters obtained from the UNIVERSAL or DREIDING force field is assigned to each model.
The results from this simulation procedure indicate that there are five possible adsorption mechanisms: (1) adsorption orientation of polymers, (2) framework form of polymers, (3) cohesion of polymers, (4) solvent effect and (5) properties of solid surface. Besides, the fourth model compared sorption of several compounds on stationary phases and in mobile phases and explains the difference of distribution between two stationary and mobile phases and the difference of retention time. In this study, the simulated models contributes to the understanding of the retention behavior and predicted the elution order of the test mixture as well as the guiding principle for the selection of a suitable stationary bonded phases and eluted solvents in bonded phase liquid chromatography.
This simulation procedure is helpful to understand the principle and operating skill of Cerius2 molecular modeling software.
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Abbas-Pour, Nima. "A Numerical Model for Oil/water Separation from an Accelerating Oil-coated Solid Particle." Thesis, 2013. http://hdl.handle.net/1807/42657.
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A computational fluid dynamics model has been developed to examine the separation of an oil film from a spherical oil-coated particle falling through quiescent water due to gravity. Using this model, the separation process was studied as a function of the viscosity ratio of oil to water, R, and the ratio of viscous forces to surface tension, represented by the Capillary number Ca. The governing equations of this flow-induced motion are derived in a non-inertial spherical coordinate system, and discretized using a finite volume approach. The Volume-of-Fluid method is used to capture the oil/water interface. The model predicts two mechanisms for oil separation: at R less than 1, the shear difference between the particle/oil interface and the oil/water interface is not significant and Ca determines whether separation occurs or not; at R larger than 1, the shear difference is considerable, and the Ca effect becomes less dominant.
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王耀貞. "The study of dissolved air floation on the solid-liquid separation technology for the wastewater treatment." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/43467551851588588367.
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Torrealba, Juan Guillermo Cartajena. "Determination of Air Flotation Parameters to Perform Solid Liquid Separation Treatment in an Activated Sludge Treating Grease Waste by Promoting Filamentous Bacteria." 2007. http://trace.tennessee.edu/utk_gradthes/272.
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The focus of this investigation was the determination of air flotation parameters to perform solid liquid separation treatment in an activated sludge treating grease waste by promoting filamentous bacteria. The treatment was intended to achieve a pretreatment level, previous to the application of the typical activated sludge process.
Generally solid liquid separation in activated sludge is performed by gravitational settling, but it is been demonstrated that the presence of an overgrowth population of filamentous microorganism in activated sludges hinder the settling properties of it. For this reason, gravitational settling may result in an inefficient treatment. Therefore, an alternative treatment has to be applied.
The treated waste in this project has a density lighter than water; additionally filamentous microorganisms tend to trap fine bubbles therefore causes floating. These specific conditions make air flotation a suitable alternative technology. The ranges of minimum operation for Dissolve Air Flotation (DAF) controlling parameters (air pressure, recycle rate, rise rate, air to solid ratio, and solids recovery) were determined. For this purpose a descriptive model for the treatment was developed. The research determined that the traditional gravitational settling was not adequate for separating the biomass from the liquid phase. In contrast dissolve air flotation showed that it was possible to achieve the pretreatment level (300 mg/L in the final effluent).
In the analysis the correlations between the parameters under study (air pressure and recycle rate) and the response variables (rise rate, air to solid ratio, suspended solids in the subnatant, and solids recovery) were determined. With the relationships defined, the minimum ranges for the parameters of operation of a DAF unit were determined. The results showed that in order to achieve the pretreatment level air pressure should range between 45-70 psi and the recycle rate between 30-35%. All the values for the rest of the response variables were determined to be within the ranges of the typical application of DAF, therefore the same equipment used for the typical application can be used to apply this treatment under these specific conditions.
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Kao, Shao-Chieh, and 高卲傑. "Integrating Eco-efficiency Model and Carbon Inventory to Evaluate the Liquid-Solid Separation for Sewage Sludge Treatment: Case Study of Electro-dewatering and PV System Compensation." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/z6etfx.
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碩士<br>國立臺灣科技大學<br>營建工程系<br>106<br>As time progresses, disposal of a large amount of solid waste becomes of great concern to many countries and needs to be solved in no time. In this study, the dewatering process of the solid waste is driven by using electric potential gradient which has lower energy consumption compared to traditional thermal drying. The municipal sewage sludge from Keya Water Recycling Center is used as an example.
According to electro-osmotic theory, mechanism and the review of pertinent experimental literatures, a series of laboratory experiments was designed to explore the impact of process parameter on energy efficiency. Furthermore, feasibility assessment of solar photovoltaic (PV) system as the backup power supply was also studied. The reduction of carbon emission equivalent can be estimated from each additional unit of energy compensation rate.
The result showed that within the range of the static pressure of 50, 150 and 200 kPa and the voltage of 10, 30 and 50 V, the water content of sludge can be reduced from 82 ± 2 % to 72 ± 2 %. The higher pressure and voltage can get the better dewatering effect. In the aspect of energy consume, the energy consumption is around 0.02~0.6 kWh/kg H2O which increases as the voltage increases. It is lower than the traditional sludge drying machine which the energy consumption is around 0.28~1.2 kWh/kg H2O.
Assuming the energy consumption is 0.2 kWh/kg H2O (when voltage equal to 30 V) and 8 tons/day sludge cake (water content from 80% to 60%) from Keya Water Recycling Center is treated, the energy consumption is about 880 kWh/day. If an 80 kWp solar PV system can be built on 800 m2 incline roof, the construction cost would be about 5 million NT dollar and its service life is about 25 years, the energy compensation rate in the spring, summer, fall and winter is corresponding to 23~31 %, 37~48 %, 26~34 % and 14~18%. When increasing each additional unit of energy compensation rate, the carbon emission can be reduced 0.87 %. Using Keya Water Recycling Center as an example, if compensation rate can reache 100 %, the carbon emission equivalent can be reduced by 482 kg-CO2e per day.
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Pereira, Andreia Filipa Dias. "Understanding colloidal speciation events of ASDs through advanced screening tools." Master's thesis, 2019. http://hdl.handle.net/10362/89618.
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Biopharmaceutics Classification System (BCS) class II and IV drugs may be formulated as supersaturating drug delivery systems (e.g., amorphous solid dispersions [ASDs]). The mechanisms that contribute to the increased bioavailability of these systems are generally attributed to the increased solubility of the amorphous form but another mechanism, with significant contributions to the improved bioavailability has been recently identified. This mechanism is related with the formation of colloidal species that are able to improve the bioavailability several fold beyond that of the amorphous drug alone. These species occur when the concentration of drug generated in solution exceeds the amorphous solubility during dissolution, resulting in a liquid-liquid phase separation (LLPS).
This work intended to implement a screening methodology to understand the ability of a drug to form colloidal species in a biorelevant dissolution media. This screening strategy was therefore focused on following the colloidal formation of itraconazole (ITZ; model drug from BCS class II) in the presence of hydroxypropyl methylcellulose acetate succinate (HPMC-AS) L, HPMC-AS M and HPMC-AS H (HPMC-AS with varying ratios of succinoyl:acetyl groups), using UV absorbance and a laser diffraction-based methodology. The ability of ITZ to form colloids by a solvent-shift approach was compared with the actual colloidal formation of ITZ amorphous solid dispersions produced by spray-drying (SDD). Results indicate that regardless of the used methodology to form supersaturated solutions of ITZ, colloids could be detected and monitored. The extension of colloid generation showed to be correlated with the SDD disintegration/dissolution rate, i.e, polymers with faster wettability kinetics led to faster SDD disintegration and colloidal formation.
As conclusion, this study showed that both laser diffraction and UV absorbance could give complementary information about colloidal formation and SDD dissolution profile, showing to be an excellent screening strategy to be applied in the early stage development of amorphous solid dispersions.