Digitized by Kansas Correctional Industries

Commercial Magnafloc 1011and in-house synthesized Al-PAM were used as flocculants for model tailings, laboratory extraction tailings and tailings from paraffin froth treatment unit. The polymers were tested for their flocculation ability in settling and filtration. For model tailings, both polymers showed excellent ability to improve the settling and filtration performance. Magnafloc 1011 is found sensitive to overdosing, but Al-PAM is not sensitive to the dosage within the tested range. For the laboratory extraction tailings, both polymers showed excellent ability to enhance settling. Al-PAM performed very well as a filtration aid. The moisture of the cake obtained from tailings derived from a low fines ore was 6.6 1.2wt% and that from a high fines ore was 16.9 0.8wt%. However, Magnafloc 1011 was found not effective as a filtration aid. For the froth treatment tailings, Al-PAM improved the settling and filterability dramatically. Although the moisture of the cake obtained was 42.5wt%, no free water is seen visually in the cake. The solid cake is self-supportive and remains intact. This class of Al-PAM polymers can provide an alternative approach for oil sands tailings disposal that can potentially eliminate tailings ponds. / Chemical Engineering

Abstract The goal of this study is to infer the nature of suspended particles from settling, advection, and resuspension processes. Previous studies have not shown that the influence of physical and biogeochemical nature on the behavior of suspended particles. Therefore we expect to observe differential hydrodynamic behavior of suspended particles of different nature in the study. The size distribution of suspended particles is a variable of sediment transport. Size and density, which play a major role in distribution of particles through the water column, are two of primary factors in determining the settling velocity of suspended particles. The sites of the field experiments were located on the Kao-ping Shelf and Kao-ping Submarine Canyon in Southern Taiwan in order to observe resuspension and settling processes. The field experiments were conducted to deploy moored instruments at the two study sites for collecting the time series data. The experiments also included profiling of temporal and special particle and hydrographic parameters along the Kao-ping Submarine Canyon using R/V Ocean Researcher III. In this study we employed a multidisciplinary approach to the study of suspended particles on a plainer inner shelf and sinuous submarine canyon. Base on the observations on the Kao-ping Shelf, the concentration of coarse-grained suspended particles near the bottom was greater than near the surface, and the fine-grained suspended particles was greater near the surface than the bottom. Coarse-grained suspended particles had better correlation with salinity of which nonlithogenic matters were the primary constituents. Fine-grained suspended particles, which consist mainly of lithogenic matters, were affected more by the current. Initial analysis of the data showed that local current speed controlled the distribution of different sizes particles. When strong currents were present, there were more coarse-grained suspended particles. Conversely, there were more fine-grained suspended particles. Regarding the temporal and special observations in the Kao-ping Submarine Canyon, the concentration of suspended particles increased with depth. The compositions of suspended particles measured by LISST-100 and water samples in the submarine canyon showed opposite trends. It revealed that different methods lead to different results. The two sediment trap arrays deployed in submarine canyon were influenced by oscillatory tidal currents. In spring tide there was high concentration of settling particles, which is composed of nonlithogenic materials. Suspended particles in the lower part of the submarine canyon did not all come from the upper part of the canyon but were transported by strong tidal currents to the observed site. The distributions of different sizes particles were the result by different hydrodynamic behavior due to nature of particles. Oscillatory tidal currents could affect the transports of suspended particles from the Kao-ping continental shelf to the Kao-ping Submarine Canyons.

Polymer-free viscoelastic surfactant-based (VES) fluid systems have been used to eliminate polymer-based damage and to efficiently transport proppants into the fracture. Current models and correlations neglect the important influence of fracture walls and fluid elasticity on proppant settling. This report presents an experimental study that investigates the impact of fluid elasticity and fracture width on proppant settling in VES fluid systems. Proppant settling experiments are performed in shear-thinning VES fluids. Experimental data is presented to show that fluid elasticity plays an important role in controlling the settling rate of the proppants. It is shown that elastic effects can increase as well as reduce the settling velocities depending upon the rheological properties of the fluid and properties of the proppants. Data is presented to show that the settling velocity reduces significantly as the proppant size becomes comparable to the fracture width. The reduction in settling velocity due to the presence of the fracture walls depends on the rheological properties of the fluid, ratio of particle diameter to fracture width as well as the diameter of the particle. / text

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Thèse (M.Eng.) -- Université du Québec à Chicoutimi, 2003. / Bibliogr.: f. [184]-191. Document électronique également accessible en format PDF. CaQCU

Dissertação(mestrado)- Universidade Federal do Rio Grande, Programa de Pós-Graduação em Geografia, Instituto de Ciências Humanas e da Informação, 2009. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-08-10T16:10:09Z No. of bitstreams: 1 dissertacao pedroso.pdf: 25800249 bytes, checksum: 6dad8829dfc67b03d9ea3ce47021e403 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-08-23T15:17:09Z (GMT) No. of bitstreams: 1 dissertacao pedroso.pdf: 25800249 bytes, checksum: 6dad8829dfc67b03d9ea3ce47021e403 (MD5) / Made available in DSpace on 2012-08-23T15:17:09Z (GMT). No. of bitstreams: 1 dissertacao pedroso.pdf: 25800249 bytes, checksum: 6dad8829dfc67b03d9ea3ce47021e403 (MD5) Previous issue date: 2009 / Neste estudo buscamos analisar alguns fatores que consideramos importantes para a formação do município de Seberi-RS. Partimos do pressuposto de que Seberi foi uma área de ocupação tardia dentro do estado do Rio Grande do Sul e, assim, buscamos compreender os motivos que acabaram transformando a porção norte do município de Palmeira das Missões em uma das últimas grandes reservas de terras disponíveis para os projetos de colonização do estado gaúcho. Buscou-se compreender os motivos que proporcionaram a valorização deste espaço, atraindo, assim, grupos de imigrantes de outras regiões do estado e a importante atuação do Estado através da Comissão de Terras e Colonização de Palmeira. E que, num período aproximado de 30 anos, tranformaram o então sertão de Palmeira em uma das áreas de maior densidade demográfica do Rio Grande do Sul. Esta dinâmica popula-cional acabou favorecendo a economia local e influenciando a formação de grupos de pessoas atuantes em cada uma das sedes distritais. Para que pudéssemos compreender a formação do município de Seberi, resgatamos aspectos históricos importantes sobre os agentes/atores que, ao se organizarem, visualizaram a possibilidade de buscar maior autonomia para o desenvolvimento de suas atividades econômicas através da emancipação do distrito de Seberi do município sede, Palmeira das Missões. / In this study we analyzed some factors that we consider important for the formation of a city called Seberi-RS. We started from the estimative that Seberi was an area of delayed occupation inside Rio Grande do Sul State, through this way, we tried to understand the reasons that turned the portion north of the city Palmeira das Missões into one of the last available land reserves for the settling project of the State. We looked for understanding the reasons that had provided the valuation of this space, attracting groups of immigrants from other regions of the state and the important performance of the State through the Land Commission and Settling of Palmeira. Who, during a period about 30 years, had transformed the hinterland Palmeira in one of the areas of bigger demographic density of Rio Grande do Sul. This dynamics population finished favoring the local economy and influencing the formation of groups of people operating in each one of the headquarters districts. For us to understand the formation of Seberi, we rescue important historical aspects on the agents/actors who, organizing themselves, had visualized the possibility to search a greater autonomy for the development of its economic activities through the emancipation of the Seberi district of the headquarter city, Palmeiras das Missões.

<p> Laboratory and field measurements were combined with theory in developing models for the various wastewater treatment processes. Some assumptions were made, both in an attempt to simplify the complex mechanisms encountered and to explain known experiences and observations. </p> <p> Models for a primary settling tank, a secondary settling tank, a generalized aerobic biological sludge treatment scheme, an anaerobic digestion system and several other unit processes have been developed. The generalized aerobic biological sludge treatment scheme is an attempt to describe in one physical package, all the various activated sludge process modifications. </p> <p> The executive system used is GEMCS · together with its library of subroutines, such as CONTLl, SEPAOl, JUNCOl and SETSPI, some of which have been modified slightly. </p> <p> The models have been tested on the Drury Lane and the Skyway, Burlington, Sewage Treatment Plants, and have been found to agree very well with plant data. The former has a conventional activated sludge process, whilst the latter employs the extended aeration modification. </p> <p> An inter-active version has been developed, which requires the minimum knowledge of GEMCS for its use. This can be applied as a training and teaching tool for plant operators and students in the field. </p> / Thesis / Master of Engineering (MEngr)

Yes / Sedimentation processes are fundamental to solids/liquid separation in water and wastewater treatment, and therefore a robust understanding of the settlement characteristics of mass fractal aggregates (flocs) formed in the flocculation stage is fundamental to optimized settlement tank design and operation. However, the use of settling as a technique to determine aggregates’ traits is limited by current understanding of permeability. In this paper, we combine experimental and numerical approaches to assess settling velocities of fractal aggregates. Using a non-intrusive in situ digital image-based method, three- and two-dimensional fractal dimensions were calculated for kaolin-based flocs. By considering shape and fractal dimension, the porosity, density and settling velocities of the flocs were calculated individually, and settling velocities compared with those of spheres of the same density using Stokes’ law. Shape analysis shows that the settling velocities for fractal aggregates may be greater or less than those for perfect spheres. For example, fractal aggregates with floc fractal dimension, Df ¼ 2.61, floc size, df > 320 μm and dp ¼ 7.5 μm settle with lower velocities than those predicted by Stokes’ law; whilst, for Df ¼ 2.33, all aggregates of df > 70 μm and dp ¼ 7.5 μm settled below the velocity calculated by Stokes’ law for spheres. Conversely, fractal settling velocities were higher than spheres for all the range of sizes, when Df of 2.83 was simulated. The ratio of fractal aggregate to sphere settling velocity (the former being obtained from fractal porosity and density considerations), varied from 0.16 to 4.11 for aggregates in the range of 10 and 1,000 μm, primary particle size of 7.5 μm and a three-dimensional fractal dimension between 2.33 and 2.83. However, the ratio decreases to the range of 0.04–2.92 when primary particle size changes to 1.0 μm for the same fractal dimensions. Using the floc analysis technique developed here, the results demonstrate the difference in settlement behaviour between the approach developed here and the traditional Stokes’ law approach using solid spheres. The technique and results demonstrate the improvements in understanding, and hence value to be derived, from an analysis based on fractal, rather than Euclidean, geometry when considering flocculation and subsequent clarification performance / Rodrigo B. Moruzzi is grateful to São Paulo Research Foundation (Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP) Grant 2017/19195-7 for financial support and to CNPq for the fellowship Grant 301210/2018-7.