Impact of Surface Miner Utilisation on Production Efficiency in Opencast Coal Mines Using Least Squares Method: A Case Study

Abstract

Surface miner ensures layer-by-layer cutting and crushing of power-grade coal simultaneously in opencast mines. This technology is proven efficient, environment-friendly and economical in Indian opencast coal mines, especially for producing coal adjacent to densely populated areas that require restricted blasting operations. This paper gives an insight into the applicability, working, advantages and utilisation of surface miner. This study was conducted in two adjacent opencast coal mines, ‘X’ and ‘Y’, of Mahanadi Coalfields Limited, Odisha, India. The range of surface miner utilisation in both mines, ‘X’ and ‘Y’, varied from 41.72 to 71.5% in a 24-h shift. A linear regression model was developed between production efficiency and the utilisation of surface miner using the least squares method for both mines having the same surface miner model. According to this model, the regression coefficient was calculated as 1.398 in mine ‘X’ and 2.001 in mine ‘Y’. As a result, 100% production efficiency was achieved at 78% utilisation of surface miner in mine ‘X’ and 54.3% utilisation in mine ‘Y’. This confirmed that despite setting a 25% less production target in mine ‘Y’ than mine ‘X’, the target was achieved with 30.38% less utilisation of surface miner, respectively. This makes mine ‘Y’ 7.71% more efficient in producing coal through surface miners than mine ‘X’. Furthermore, the model determined that mine ‘Y’ achieved the same coal production with 7.16% lesser machine shift time than mine ‘X’, which further concludes that the target production of any surface miner should complement its technical specifications as well as its actual range of utilisation in a particular mine. © The Institution of Engineers (India) 2023.