Factor Intensity and Site Geology as Determinants of Returns to Scale in Coal Mining
نویسنده
چکیده
-Increasing returns to scale (RTS) is frequently postulated as affecting productivity in surface coal mining. However, it is not clear whether increased capital intensity or increased output is the relevant phenomenon. A ray-homothetic production function that incorporates the capital-labor mix and fixed site geology into the scale elasticity is presented and estimated with a micro (mine level) dataset. The results indicate that higher capital intensity contributes to higher RTS for some types of capital equipment, but not all. On the average increasing RTS was found, with few mines approaching optimal scale.
منابع مشابه
Fundamentals of 3D modelling and resource estimation in coal mining
The prerequisite of maintaining an efficient and safe mining operation is the proper design of a mine by considering all aspects. The first step in a coal mine design is a realistic geometrical modelling of the coal seam(s). The structural features such as faults and folding must be reliably implemented in 3D seam models. Upon having a consistent seam model, the attributes such as calorific val...
متن کاملImprovement of coal mine roof rating classification using fuzzy type-2
One of the main concerns of an underground coal mining engineer is the safety and stability of the mine. One way that the safety and stability can be ensured is to know and understand the coal mine geology and how it reacts to the mining process. One technique that has shown a lot of success in the coal mining industry for geologic technical evaluation purposes is the coal mine roof rating (CMR...
متن کاملGeological and Geochemical Features of Alborz Basin Coal Deposits, Iran
The Alborz coal basin is located in northern part of Iran. The coal deposits of Shahrood in eastern Alborz, Zirab in central Alborz and Abyek in western Alborz were studied as typical coalfields of the basin. Shemshak Formation which is the main coal-bearing sequence was formed during the Triassic-Jurassic in the basin. It consists of sandstone, siltstone, shale and claystone, which variedly al...
متن کاملInvestigating the effect of fractures on unusual gas emission in coal mines; case study of Parvadeh coal mine, Iran
In the present study, an investigation was carried out on Parvadeh coal mine in Tabas, Iran, to survey the effect of fractures on unusual methane gas emission in coal mines. This coal mine was chosen for investigating because of its high methane gas content in the coal body and available data from sensors in desired locations. Gas concentration monitoring programs were carried out at the mine s...
متن کاملApplying rock engineering systems (RES) approach to evaluate and classify the coal spontaneous combustion potential in Eastern Alborz coal mines
Subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. Empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. The Rock Engineering Syst...
متن کامل