Improving Energy Efficiency of Coal Transportation by Adjusting the Speeds of a Combine and a Mine Face Conveyor

Abstract

The object of this research is the process that forms the weighted specific energy consumption for the transportation of rock mass by a coal face scraper conveyor at intensive coal mining under conditions of the non-uniform movement of a cleaning combine. The subject of this study is the regularities in the influence of uneven feed speed of a cleaning combine on energy indicators for the transportation of breakage face by a scraper conveyor under conditions of intensive coal mining. The aim of this work is to substantiate a technique to improve energy efficiency in the operation of the system "Cleaning combine ‒ mine face conveyor" under intensive coal mining conditions. We have statistically processed the results of experimental research into feed speed of the cleaning combine KDK500 at the eastern coal face No. 23 of deposit с11 at the mine "Yuzhnodonbasskaya" (Ugledar, Ukraine) of GP "Donetskugol", undertaken by the Institute "Dongiprouglemash" (Ukraine). We have constructed the structural and mathematical models of the process that enables the output cargo flow of breakage face and forms specific energy consumption for the transportation of rock mass by a coal face scraper conveyor. A mathematical model of the operating process takes into consideration the impact of the magnitude and non-uniformity of the feed speed of a cleaning combine on energy consumption at cargo transportation. We have established significant non-uniformity in the speed modes, in the productivity of a cleaning combine, caused by the mining-geological conditions and the nature of the technological process, by existing procedures for harmonizing the operational modes of mining and transporting equipment at breakage faces. The influence has been established of speed modes and efficiency of the combine on specific energy consumption for the transportation of cargo by a coal face scraper conveyor. The result is the high irregularity of a cargo flow both along a coal face and along further transport chain, which leads to a significant increase in energy consumption for cargo transportation. We have examined the effect of speed modes during operation of a combine, consequently its efficiency, on energy indicators for the process of coal transportation and the distribution of a cargo flow. It was established that increasing the feed speed of a cleaning combine and decreasing the speed of a scraper conveyor bring down specific energy costs for the transportation of discharged rock mass along a coal face.