Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. Description based on print version record. Includes bibliographical references.

Teve como objetivo verificar e comparar a alteração das características do carvão antracitoso e do carvão betuminoso utilizados em meio filtrante, devido ao efeito abrasivo causado entre os grãos decorrentes de lavagens exclusivamente com água e lavagens independentes com ar e água. Foram estudados dois tipos de carvão antracitoso e um tipo de carvão betuminoso, para os quais foram determinadas suas características químicas e físicas. Os ensaios foram realizados em uma instalação ao piloto montada na escola de engenharia de São Carlos-EESC, USP, na qual foram feitas simulações de lavagens admitindo-se uma lavagem diária durante um ano para cada método, de modo intermitente, em que o meio granular era compactado ao final de cada lavagem, e continuo, sem compactação do meio granular. A velocidade ascensional utilizada para cada simulação de lavagem foi de 0,9 m/min, promovendo expansão no meio granular de 35 a 40%. A taxa de ar utilizada para as simulações de lavagens com aplicação de ar foi de 15 l/sm2. Após o término das 365 lavagens, foram determinados os valores médios do coeficiente de esfericidade e da porosidade do meio granular estratificado e construída a curva de distribuição granulométrica das amostras utilizadas nos ensaios. Conclui-se que o carvão betuminoso apresentou comportamento semelhante ao dos carvões antracitosos e que a metodologia de lavagem continua produz praticamente o mesmo efeito abrasivo comparada a de lavagem intermitente. / This work had the objetive to verify and to compare the alterations on the properties of Anthracite coal and Betuminous coal, due to the abrasive effect caused between the grains resulted from washing exclusively with water and independent washing with air and water. There were studied two types of Anthracite coal and one type of Betuminous coal, their chemical and physical properties were determined. The tests were performed at a pilot instalation setted at the School of Engineering of São Carlos - EESC,USP; where, were done simulations of washing, it was admitted one washing a day during one year (365 washing) for each method, in an intermitent way, in which the granular medium was compacted at the end of each washing, and continous without compactation of the granular medium. The ascending speed used for each simulation of washing was 0,9 m/min, promoting an expansion in the granular medium of 35 to 40%. The rate of air used for the simulations of washing with the aplication of air was 15 I/sm2. After the last of the 365 washing, were determined the average values of the coefficient of sphericity and porosity of the granular estratified medium and was constructed a curve of the granulometric distribution of the samples used during the tests. It was conclued that Betuminous coal shows similar behaviour as Anthracite coaI and the continous method produce the same effect abrasive compared intermitent method.

This masters’ thesis deals with a thermal design of a draft dry bottom boiler for bituminous coal that should replace a disassembled boiler in a current boiler room. Application of SCR is intended in order to reach emission standards of NOx.

No description available.

This master´s thesis deals with the constructional and calculation design of the boiler for burning wood and sub-bituminous coal. The work is divided into several parts. First, stoichiometrics calculation and enthalpy calculations of air and flue gas are performed. It is calculated heat balance of the boiler, the boiler losses and the thermal efficiency of the boiler is determined. After designing the combustion chamber thermal calculation is made. Then, the dimensions and individual heating surfaces are proposed. At the end of the calculations are controlling the overall energy balance.

MESMEG / Department of Mining and Environmental Geology / The Mushithe coal occurrence is situated approximately 16 km west of the Tshikondeni coal mine in the Tshipise-Pafuri sub-basin of the Soutpansberg coalfield in South Africa. The Soutpansberg Coalfield has received comparatively less attention compared to other more notable South African coalfields. There is as a consequence very limited information in the public domain applicable to the geology as well as quality of coal in this coalfield, as a result there is no known study focused exclusively on the Mushithe coal occurrence. The aim of the study was to conduct detailed geological mapping of the Mushithe Deposit so as to ascertain the geological environment and petrological characteristics of rocks within the area. Further work involved coal sampling and analysis in order to establish coal quality and its physical and chemical characteristics. Samples were collected using geological field mapping and channel sampling. Nine coal samples were collected from the coalbed and host rock, exposed along the Mbodi River, during geological field mapping using channel sampling. Furthermore, 92 rock samples were collected during geological field mapping of which 10 representative samples were selected for further analysis. X-ray fluorescence spectrometry was conducted on all selected samples. Proximate analysis and ultimate analyses, and calorimetry tests were undertaken on coal samples. Three samples were selected based on calorific value for maceral identification, mineral analyses and vitrinite reflectance using petrographic study. Detailed geological mapping of the area around the Mushithe coal occurrence showed the geological setting of coal in this area. The following lithologies were identified in the study area: sandstone, mudstone, ironstone, calcrete, shale, quartzite, quartz vein with a general strike direction to the north-east. The host rocks including coal were intruded by dolerite dykes and this resulted in the devolatilization of coal. The current study concluded that the Mushithe coal was formed in a wet swampy environment. This has been confirmed based on tissue preservation index (1.69) and gelification index (2.35). Coal rank ranged from bituminous Rank C- B according to United Nations Economic Commission for Europe Coal Classification (UNECE) and samples were characterised by high ash (27.90%), high moisture (10.47%) and low sulphur (0.24%). Furthermore, coal was graded below grade D based on classification for use by ESKOM which consider any calorific value below 24.5 MJ/kg to be in this category. The coal is vitrinite rich (77.75 vol%) and low in Inertinite (22.25 vol%) and devoid of Liptinite and pseudovitrinite, thus it is of good coking quality. Geochemical analysis revealed that the coal was enriched in TiO2 and Fe2O3 which was corroborated by the mineral matter which was mostly clay and pyrite. Comparatively, coal quality analysis revealed the calorific value of 14.26 MJ/kg and vitrinite reflectance between 0.94 %ROV to 1 %ROV which was less than that of the Tshikondeni Deposit but greater than that at Waterberg coalfield. The study recommends further detailed exploration of coal in the area, applying such techniques such as geophysical exploration and borehole drilling leading to resource evaluation. Further studies are recommended to provide a better interpretation of the depositional environment of coal at Mushithe as well as the effect of devolatilaziton by a dolerite dyke. / NRF