Energy performance of loading and hauling operations in opencast mines

Abstract

Loading and hauling machines accounts for significant share of the total energy usage in large opencast mines. Major share of power is consumed in electric shovels used for loading operations and accounts for 32% of the total electricity usage in mine. Diesel is also used for operating hauling machines (dump trucks) in opencast mine and accounts for 56% of the total diesel consumption. In this paper, a methodology is proposed for calculating overall energy consumption in major energy intensive mining processes such as loading and hauling operations of the coal mine. Statistical approach has been used to estimate minimum SEC of a specific mine based on the annualized data. A linear regression method has been used to develop a mine specific model for estimating SEC by the correlation between SEC and composite production. A case study of an Indian opencast mine is presented to illustrate the results. Minimum SPC of electric shovels is calculated as 0.15 kWh/cum whereas the best operating SDC values of dump trucks operating in same mine is 0.47 l/cu.m. The overall SEC of loading and hauling operations calculated for the same opencast mine is 17.76 MJ/Cu.m and SEC of total operation in mine is 27.2 MJ/Cu.m. The best practices opencast mine without dragline from the literature is 26.3 MJ/cu.m.