通风模型在掘进的应用和加拿大煤炭资源在社会和政治上限制的影响毕业论文外文翻译.doc

附录AVentilates the model in the tunneling application with Canada coal resource the influence which limits in the society and politics The extraction of minerals and coal at greater depth, employing higher-powered machinery to increase production levels has imposed an increased burden on ventilation systems to maintain an acceptable working environment. A deterioration in the climate experienced within these workings may also adversely affect the health and safety of the workforce. In the UK, mineral extraction is now being practiced at depths of over 1000 m. In addition, the adoption of continuous miner and tunnel bolting support methods has permitted improved development rates to be achieved at the cost of increased emissions of dust, gas and heat and humidity. There is a recognized need to improve the efficiency in the design and operation of auxiliary ventilation systems to maintain an adequate underground environment and climate. Any improvement achieved in the quality, quantity and control of the delivered ventilation will assist in the provision of improved gas and dust dilution and climatic control. Due to the constraints imposed by the mining method, there may be an economic or practical limit to the climatic improvement that may be obtained by the sole use of ventilation air. Where this limit is identified, there may be the need to consider the selective application of air-cooling systems. The paper details the construction of a computer based climatic prediction tool developed at the University of Nottingham. This work builds upon earlier research (Ross et al., 1997, Proceedings of 6th International Mine Ventilation Congress, SME, Littleton, CO, pp. 283–288) that developed a prototype model for short tunnel developments. The current model predicts the psychrometric and thermodynamic conditions within long rapid development single entry tunnel drivages. The model takes into account the mass and heat transfer between the strata, water, machinery and the ventilation air. The results produced by the model have been correlated against ventilation, climatic and operational data, obtained from a number of rapid tunnel developments within UK deep coalmines. The paper details the results of a series of correlation and validation studies conducted against the ventilation and climate survey data measured within 105s district Tail Gate tunnel development at Maltby Colliery, UK. The paper concludes by presenting the results of a case study that illustrate the application of the validated model to the design and operation of an integrated mine ventilation and cooling system. The case study illustrates the effect that an increased depth and hence increased virgin strata temperature has on the climate experienced within rapid tunnel developments. Further investigations were performed to identify the optimum cooling strategy that should be adopted to maintain a satisfactory climate at the head of the drivage.A coal resource estimate should reflect the wealth that coal endows to the land within which it occurs. It forms the basis for long term public and commercial planning in areas such as future coal supply possibilities, and land use options. Coal beds occur in a variety of forms and amounts in most sedimentary basins in Canada. Coal bed thickness, depth form surface, geographical location and coal quality are primary indicators of a deposit’s potential utility Exploitation of some coal deposits is currently unfeasible for economic and/or technological reasons associated with the nature of their occurrence. Some of these deposits may become viable sources of coal, or coal-derived products, in the foreseeable future as technologies advance and economic conditions change. Other deposits, such as those that are extremely deep or thin, have no imaginable future utility and are not included in estimates of the nation’s coal resources.Most of this report focuses on Canada’s coal resources of immediate interest (refer to Chapter 2). Additional large quantities of coal that might be exploited in the foreseeable future given more favourable economical, technological, and/or statutory conditions are classified as coal of future interest.Resources of future interest generally consider coal that are less than 60cm thick (with the exception of resources in New Brunswick, where thinner beds are currently mined), occurring at depths that are greater than 600m from surface, (with the exception of resources in Nova Scotia, where mining to much greater depths is currently planned). For relatively thin coal beds to be considered resources of future interest where underground mining is the likely coal extraction method, they must contribute to a minimum aggregate thickness of 1.5m with other beds in close proximity. This is often referred to as a coal zone or mining zone.Coal is the most abundant fossil in Canada and in the rest of the world.It currently represents about 14 per cent of Canada/s primary energy economy. t。