Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on July 15, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Engineering Management, Department of Mechanical Engineering, University of Alberta. Includes bibliographical references.

Thesis (Ph.D.)--University of Tulsa, 1987. / Bibliography: leaves 222-226.

Thesis (Ph. D.)--University of Adelaide, Dept. of Chemical Engineering, 1988? / Typescript (Photocopy). Includes bibliographical references (leaves 196-205).

The analytical advantages of some novel approaches to atomisation using gaseous sample transport and slurry nebulization have been investigated and applied to the determination of trace metals in coal. A cold vapour atomic fluorescence spectroscopic method for the determination of mercury using a gas-sheathed atom cell and front surface illumination was developed. With a manual injection technique the detection limit was 0.01 ng. Replacement with a continuous flow system yielded a more rapid and precise method with a detection limit of C.045 ng.ml-1. Quantitative recoveries of mercury from a standard coal were obtained through liberation of the analyte using nonoxidative pyrolysis. Continuous hydride generation methods for the determination of arsenic and selenium using atomic absorption and atomic fluorescence spectrometry were developed.

Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2016. / This dissertation presents how material properties (solids densities, particle size distributions, particle shapes and concentration) of gold tailings slurries are related to their rheological parameters, which are yield stress and viscosity. In this particular case Bingham yield stresses and Bingham plastic viscosities. Predictive models were developed from analysing data in a slurry database to predict the Bingham yield stresses and Bingham plastic viscosities from their material properties. The overall goal of this study was to develop a validated set of mathematical models to predict Bingham yield stresses and Bingham plastic viscosities from their material properties. The interaction of the non-Newtonian material properties is very complex at varying mass solids concentrations. The evaluation of these interactions in terms of constitutive equations is almost impossible and the relationship between material properties, mass solids concentration and rheology can only be modelled in a statistical manner. The validity of each model is checked to ensure that predictions and interpretations are unbiased and efficient. This is done by comparing the resulting models to experimental data generated from test work. An in-depth analysis was conducted to see the interrelationship between the material properties and how they affect the yield stress and viscosity values.

Recent interest in producing superclean coal has lead to the development of coal cleaning techniques which require the grinding of coal to sizes below 10 microns. Coal in this size range has inherent material handling problems, most of which can be eliminated by the utilization of this ultrafine coal in a slurry form. Ultrafine coal-water slurries, prepared from an Eastern bituminous coal, are investigated to determine the effect of size distribution on slurry rheology. The effect of reagent addition on slurry rheology is normalized by conducting experiments at optimum additions determined to maximize particle dispersion. As a result of this investigation, it has been found that the maximum solids loading for ultrafine coal slurries ranges from 55 to 60 percent by weight as compared to 70 to 75 percent solids reported for coarser slurries. It was further shown that as particle size decreases there is an increase in slurry viscosity and a corresponding decrease in maximum solids loading. Continued analysis in view of a suspension viscosity model (Lee, 1970) yields unsatisfactory predictions as compared to the experimental results. Modification of this model by incorporating a volume correction factor improves the correlation between model predictions and experimental results. The volume correction factor reflects an increase in apparent solids loading which becomes greater as the particle size decreases. Also investigated is the effect of various reagents on the rheology of ultrafine coal slurries. Pseudoplastic or dilatant slurry rheologies are shown to be more dependent upon dispersing reagent than the size distribution. / M.S.

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PhD, Faculty of Engineering, University of the Witwatersrand, 1990

a b s t r a c t A slurry nebulisation technique was applied for elemental analysis of bituminous coals SARM 18, SARM 19 and four coals from three different seams in Witbank, South Africa, by inductively coupled plasma optical emission spectroscopy (ICP-OES). Major elements (Al, Ca, Fe, Mg, S, Si and Ti) and trace elements (Ba, Cr, Mn, Ni, Sr, V, Zn and Zr) in coal were determined. Various slurry preparations were evaluated using two dispersants (glycerol and Triton X-100) and by varying the concentration of dispersants, between 0.1% and 1.0% (v/v). The effect of initially solubilising the ground coal in N,N-dimethylformamide (DMF) was investigated by varying the volume of DMF added. The effect of wet grinding with DMF was investigated. Wet grinding with DMF was shown to drastically reduce particle sizes (50.0% < 0.28 lm and 90.0% < 6.17 lm) as compared to dry grinding (50.0% < 5.25 lm and 90.0% < 11.1 lm). The reduced particle sizes and increased transport efficiency of the coal slurries led to improved analytical recoveries of elements in the reference coal, SARM 18. The best analytical recoveries for all elements were achieved using 0.1% Triton X-100 with 10.0% DMF. Results obtained by ICP-OES after wet grinding of the coal with DMF, using 0.1% Triton X-100, also gave excellent recoveries (Al, 100%; Ca, 103%; Cr, 106%; Fe, 102%; Mg, 100%; Mn, 104%; Ni, 109%; Si, 102%; Ti, 95.0%; and V, 108%). The results obtained with 10.0% DMF and 0.1% Triton X-100 were in agreement with certified values for all selected elements according to paired t-test at the 95.0% confidence level. Selected elements (Al, Ca, Fe, Mg, Mn, Si, Ti and V) were also analysed with X-ray fluorescence for comparison with results obtained from ICP-OES. Analysis by ICP-OES of microwave digested coal was also carried out. It is suggested that the DMF slurry technique could be used for routine analysis of bituminous coals.