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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Measuring wall forces in a slurry pipeline

El-Sayed, Suheil Unknown Date
No description available.
92

Nitrogen and phosphorus in soil and groundwater following repeated nitrogen-based swine slurry applications to a tame grassland on coarse textured soil

Coppi, Luca 08 January 2013 (has links)
Swine slurry is a source of nutrients to grasslands. However, accumulation of N or P can lead to their movement to groundwater. This thesis’ research was conducted using a tame pasture fertilized over six years with swine slurry at N-requirement rates, on a gravelly soil in south-eastern Manitoba. Objectives were to determine N and P soil surplus and accumulation over time, soil profile P fractions and soil surface P saturation, and nitrate and dissolved-P in shallow groundwater for treatment combinations of forage utilization (Hay and Grazed), slurry application in spring (Single), split in fall and spring (Split) and no slurry (Control), and Grassed areas of grazed paddocks and Bare areas where cattle congregated around water troughs. There were less surplus and accumulation of extractable-P in the soil surface for the Split compared to the Single treatment because of less P in fall- than in spring-applied manure. With Grazing, there were greater surpluses of N and P than with Haying, and surface accumulation of extractable-P over time was linear being 16.5 and 11.9 mg P kg-1 year-1at 0-5 cm for Grazed and Hay treatments, respectively. Labile inorganic-P fractions (water- and bicarbonate-extractable) increased in the Bare and in the Single Grassed treatments. In the Bare treatment, P-sorption capacity at 0-5 cm decreased compared to the Grassed treatment. The surface soil of the Bare areas had large concentrations of water-soluble-P up to 165 mg P kg-1 associated with an increase in P-saturation to 88 % of the sorption capacity, and nitrate was elevated in the soil profile. Concentrations of nitrate-N and dissolved-P in groundwater were below the environmental thresholds of 10 mg nitrate-N L-1 and 0.025 mg P L-1, respectively, in both the Hay and the Grazed Grassed treatments. In contrast, the Control and Single Bare treatments had nitrate concentrations always above the threshold, and the Bare areas in the Single paddocks had P concentrations of environmental concern in 2009, averaging 0.7 mg total dissolved P L-1. Nitrogen-based slurry applications did not cause leaching of N or P, but Bare areas in grazed pastures are at risk of N and P leaching.
93

Nitrogen and phosphorus in soil and groundwater following repeated nitrogen-based swine slurry applications to a tame grassland on coarse textured soil

Coppi, Luca 08 January 2013 (has links)
Swine slurry is a source of nutrients to grasslands. However, accumulation of N or P can lead to their movement to groundwater. This thesis’ research was conducted using a tame pasture fertilized over six years with swine slurry at N-requirement rates, on a gravelly soil in south-eastern Manitoba. Objectives were to determine N and P soil surplus and accumulation over time, soil profile P fractions and soil surface P saturation, and nitrate and dissolved-P in shallow groundwater for treatment combinations of forage utilization (Hay and Grazed), slurry application in spring (Single), split in fall and spring (Split) and no slurry (Control), and Grassed areas of grazed paddocks and Bare areas where cattle congregated around water troughs. There were less surplus and accumulation of extractable-P in the soil surface for the Split compared to the Single treatment because of less P in fall- than in spring-applied manure. With Grazing, there were greater surpluses of N and P than with Haying, and surface accumulation of extractable-P over time was linear being 16.5 and 11.9 mg P kg-1 year-1at 0-5 cm for Grazed and Hay treatments, respectively. Labile inorganic-P fractions (water- and bicarbonate-extractable) increased in the Bare and in the Single Grassed treatments. In the Bare treatment, P-sorption capacity at 0-5 cm decreased compared to the Grassed treatment. The surface soil of the Bare areas had large concentrations of water-soluble-P up to 165 mg P kg-1 associated with an increase in P-saturation to 88 % of the sorption capacity, and nitrate was elevated in the soil profile. Concentrations of nitrate-N and dissolved-P in groundwater were below the environmental thresholds of 10 mg nitrate-N L-1 and 0.025 mg P L-1, respectively, in both the Hay and the Grazed Grassed treatments. In contrast, the Control and Single Bare treatments had nitrate concentrations always above the threshold, and the Bare areas in the Single paddocks had P concentrations of environmental concern in 2009, averaging 0.7 mg total dissolved P L-1. Nitrogen-based slurry applications did not cause leaching of N or P, but Bare areas in grazed pastures are at risk of N and P leaching.
94

Treatment of oily drill cuttings slurries using supercritical carbon dioxide

Jones, Christopher Robert 06 1900 (has links)
Research was conducted into using supercritical fluid extraction (SFE) for removing hydrocarbons from drill cuttings slurries, which will be used in a pilot-scale continuous SFE system currently under development. A laboratory-scale batch SFE system employing supercritical carbon dioxide (CO2) was used in this research. Based on the measured hydrocarbon solubility and apparent hydrocarbon solubility in supercritical CO2, conditions of 14.5 MPa and 40oC were selected for SFE treatment. The slurries require a minimum water to drill cuttings ratio of 1:1 (mass basis) to be free-flowing and therefore suitable for treatment in a continuous system. Water in the slurries leads to lower hydrocarbon extraction efficiencies during SFE treatment compared to the treatment of drill cuttings without slurrying. However, effective mixing and introduction of the supercritical CO2 at the bottom of the extraction vessel resulted in treated slurries containing less than 1% hydrocarbons (dry mass basis). / Environmental Engineering
95

Fly-ash particulates analysis of no. 6 fuel oil and coal-oil-water slurries in a small industrial boiler

Zronek, Steven C. January 1986 (has links)
Thesis (M.S.)--Ohio University, June, 1986. / Title from PDF t.p.
96

Modelling the effect of mill length on the relationship between slurry hold-up and flowrate /

Tello, Sebastian. January 2002 (has links) (PDF)
Thesis (M.Eng.Sc.)--University of Queensland, 2003. / Includes bibliography.
97

OHD Processing of Coal Waste Materials

Tobin, Amberly Hope 01 December 2016 (has links)
AN ABSTRACT OF THE THESIS OF Amberly Hope Tobin, for the Master of Science degree in Organic Geochemistry, presented on August 4th 2016, at Southern Illinois University Carbondale. TITLE: OHD PROCESSING OF COAL WASTE MATERIALS MAJOR PROFESSOR: Dr. Susan M. Rimmer This research addresses coal-waste utilization via the OHD process and the implications for both economic and environmental impacts. The goal of this project is to determine if coal-waste products can be processed by the OHD technique. Furthermore, this project will determine what types of products are produced from the coal-waste materials and will compare these to those produced by the OHD processing of raw coal. This research has the potential to be beneficial to the coal industry as OHD would allow production of high-value products from what is currently viewed as a waste material; additionally, this research will provide a way to recycle what is considered a hazardous waste product and provide an incentive to reclaim coal slurry ponds that are an environmental concern. A preliminary suite of grab samples from an active coal slurry pond along with a stream reject sample were obtained in order to determine if these types of materials could be processed via OHD. After these samples were deemed viable in the OHD process, core samples were taken from a large slurry pond. These cores were then ii sampled at 2 ft (0.61 m) intervals. The key analyses performed were geochemical, petrographic, OHD, and GC-MS. Geochemical analysis included carbon, sulfur, moisture, volatile matter, ash, and fixed carbon content of the coal-waste samples before OHD, and provided a basis for comparison with raw coal samples. Petrographic analysis was performed to determine the maceral composition before the OHD processing. The OHD process is the core technique of this research project. The preliminary slurry pond samples were processed in a small semi-continuous OHD reactor. While the stream reject and slurry pond core samples were processed using a continuous OHD reactor, as this type of reactor is best suited for fine-grained slurries. GC-MS was used to examine the OHD liquid products analysis in order to determine the types of compounds present in the final liquefied product; these products were then compared to raw coal OHD products in order to determine their economic potential. Petrography of the coal-waste materials showed that these samples did contain a notable amount of coal; predominantly vitrinites and inertinites were observed in the samples. Geochemical analysis proved that there were significant amounts of organic carbon in these materials, ranging between 25 and 37%. OHD processing was successful on all coal-waste materials, although the continuous OHD reactor tended to work better with the fine-grained slurries than the semi-continuous OHD reactor. The GC-MS analysis of the coal-waste OHD product showed very similar suites of compounds to that of a bulk coal OHD product; in general, almost all major compounds that are found in a typical coal OHD product were also found in the coal-waste OHD products. This suggests that these slurry ponds, which are typically regarded as waste products, could be viable feedstocks for OHD processing.
98

\"Validação da metodologia analítica para a determinação do diclofenaco sódico em amostras de esgoto da estação de tratamento da cidade de Araraquara-SP\" / \"Validation of an analytical methodology to the determination of sodium diclofenac in slurry samples from the water treatment station of Araraquara-SP\"

Keila Angélica Peron 26 March 2007 (has links)
Os resíduos de fármacos presentes em matrizes ambientais têm sido foco em pesquisas no mundo todo. Este tema tem sido bastante discutido devido ao fato de que fármacos são freqüentemente encontrados em efluentes de estações de tratamento de esgotos (ETE´s), águas de abastecimento público e em outras matrizes ambientais, tais como solos, sedimentos e águas naturais em concentrações na faixa de µg L-1 e ng L-1. A grande preocupação da presença de resíduos de fármacos na água são os potenciais efeitos adversos para a saúde humana, animal e de organismos aquáticos. Neste trabalho estudou-se o diclofenaco sódico, por ser um dos antiinflamatórios mais prescritos pelos médicos. O método utilizado para a extração do diclofenaco sódico de amostras de efluentes domésticos da ETE de Araraquara-SP foi à extração em fase sólida, e subseqüentemente a determinação por cromatografia líquida de alta eficiência com detector UV. O método foi validado e a recuperação foi de 94-105%. Constatou-se a presença do diclofenaco sódico nas amostras do efluente doméstico da cidade de Araraquara-SP antes e após o tratamento e as concentrações foram 2,12 e 3,52 µg L-1 na coleta feita em março e 18,0 e 22,0µg L-1 na coleta feita em setembro. / The pharmacos residues that are present in the environmental matrices has been a focus of research all over the world. This subject has been discussed because the fact that pharmacos are frequently found in effluents of sewage treatment plants (STPs), public water supply and in others environmental matrices, such as the soil, sediments and water springs in concentrations between µg L-1 and ng L-1. The biggest concern of pharmacos residues in the water are the adverse effects for the human health and the other species too. So, in this research the sodium diclofenac was studied for being the most prescribed anti-inflammatory by the doctors. The method used for the extraction of the sodium diclofenac of samples from the domestic effluent at STP-Araraquara (SP) was the extraction in solid phase, and subsequently the determination by liquid chromatography of high efficiency with UV detector. The method was validated and the recovery was of 94 to 105%. The results of the research have shown the presence of sodium diclofenac in the samples of Araraquara\'s domestic effluent before and after the treatment and the concentrations were 2,12 and 3,52 µg L-1 in the collection made in March and 18,0 and 22,0µg L-1 in the collection made in September.
99

Particle Interactions in Industrial Granular Systems: Experiments, Theory, and Simulations

Patil, Deepak C. 01 May 2017 (has links)
Granular media continue to be among the most manipulated materials found in various industries. Particle interactions in granular flow has fundamental importance in analyzing the performance of a wide range of key engineering applications such as hoppers, tumblers, and mixers etc. In spite of such ubiquitous presence, till date, our understanding of the granular flow is very limited. This restricts our ability to design efficient and optimal granular processing equipment. Additionally, the existing design abilities are also constrained by the number of particles to be analyzed, where, a typical industrial application involves millions of particles. This motivated the current research where investigations on the above limitations are pursued from three different angles: experimental, theoretical, and simulation. More specifically, this work aims to study particle-wall interaction and developing a computationally efficient cellular automata simulation framework for industrial granular applications. Towards this end, the current research is divided into two part: (I) energy dissipation during particle-wall interaction (II) cellular automata modeling. In part I, detailed experiments are performed on various sphere-thin plate combinations to measure the coefficient of restitution (COR) which is a measure of energy dissipation and it is one of the most important input parameters in any granular simulation. Alternatively, the energy dissipation measure also used to evaluate the elastic impact performance of superelastic Nitinol 60 material. Explicit finite element simulations are performed to gain detail understanding of the contact process and underlying parameters such as contact forces, stress-strain fields, and energy dissipation modes. A parametric study reveals a critical value of plate thickness above which the effect of plate thickness on the energy dissipation can be eliminated in the equipment design. It is found that the existing analytical expressions has limited applicability in predicting the above experimental and numerical results. Therefore, a new theoretical model for the coefficient of restitution is proposed which combines the effect of plastic deformation and plate thickness (i.e. flexural vibrations). In part II, in order to advance the existing granular flow modeling capabilities for the industry (dry and slurry flows) a cellular automata (CA) modeling framework is developed which can supplement the physically rigorous but computationally demanding discrete element method (DEM). These include a three-dimensional model which takes into account particle friction and spin during collision processing, which provides the ability to handle flows beyond solely the kinetic regime, and a multiphase framework which combines computational fluid dynamics (CFD) with CA to model multi-million particle count applications such as particle-laden flows and slurry flows.
100

An investigation into the development of a portable, ultrasonic, density measuring instrument

Hulse, Nigel Douglas January 1987 (has links)
Dissertation submitted in compliance with the requirements for the Master's Diploma in Technology: Electrical Engineering (Light Current), Technikon Natal, 1987. / In the gold mining industry, one of the significant physical properties of the mineral slurry is its density and it is important to be able to measure this parameter in most processes. There are many techniques for determining the density of fluids, but because of the hostile, abrasive nature of mineral slurry, very few of these are suitable, This dissertation describes the deveiopment, construction and testing of a portable, ultrasonic, density measuring instrument. The instrument uses an ultrasonic transducer as the primary measuring element, and system operation is based on the fact that the driving impedance of the transducer varies with changes in the physical properties, and hence the characteristic impedance, of the surrounding medium into which the ultrasonic energy is being transferred. The technique may a-Lao be used to measure the relative concentrations of two liquids in a mixture or emulsion, provided that the characteristic impedances of the liquids are sufficiently dissimilar. The electronic circuitry is fairly straightforward, consisting essentially of an oscillator, driving circuit for the transducer and a voltage monitor to provide a d.c. voltage proportional to the impedance of the transducer, and hence to the density of the surrounding medium. Most of the research has been concentrated on the probe design, as the type of transducer, the type and thickness of facing material and the method of construction all contribute to the sensitivity of the instrument. A design of probe assembly has been developed that may be used for both slurry density measurement and the measurement of the ratio of aqueous to organic liquids in emulsion. / M

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