Turkish Coal Enterprises Research Articles

An equipment selection and cost analysis system for openpit coal mines

Turkish Coal Enterprises (TKI) is the largest coal producer of Turkey, The majority of coal stripping is done by private contractors and the decision for a contractual agreement is dictated by two relevant problems. The first problem is selection of size, type and number of major equipment that would yield the minimum unit cost for a stripping job. The second problem requires determining whether the given stripping job can be completed by the due date using whatever equipment is available to the contractor. The latter case considers the situation where the contractor's equipment is not the optimum but the job can still be finished with less profit. Two optimization models are developed to overcome these problems. To establish efficient and practical criteria for the selection of excavation method, an extensive study is carried out in the surface coal mines of Turkish Coal Enterprises and the diggability classification developed as a result of this study is the basis of the models. The first model is the equipment selection model that aims to select the equipment fleet minimizing the unit stripping cost. The second model is the equipment evaluation model that aims to maximize the production done with a given equipment fleet. The models assume that the stripping is done by excavator-truck system. Besides the loading-hauling operations, material preparation and the activities required in the dump area are also handled by the models in order to evaluate the overburden removal operation as a whole.

Performance assessment of hydraulic and cable shovels

Abstract In this paper, performance assessment studies for hydraulic and cable shovels carried out on a nationwide scale in the surface lignite mines of Turkish Coal Enterprises are explained. The work was involved manual stopwatch surveys of shovel dig cycle times, estimation of bucket filling and hourly excavation capacity of shovels. The accumulated data is compared with the literature values in order to be evaluated in terms of ease of digging. The observed bucket size ranges of hydraulic and cable shovels varied from 2,5 to 10.5 and 4.5 to 25 yd respectively. The work efficiencies were established by considering observed and net outputs. Furthermore, the performance results were cooperated with geotechnical data to define the ease of digging.