Modelling the flow of a non-homogeneous ore is an important element needed to identify ore parameters for the purpose of ore processing control. The simulation model of the underground ore haulage system with the implemented function of estimating ore qualitative and quantitative parameters was built in the dedicated FlexSim simulation environment to address this issue. The transported ore is averaged in transfer and retention points, for instance in ore bunkers. This fact renders the modelling of ore flow inside the bunker a necessary part of the simulation. The movement of the granulated material, restricted by the geometry of the floor and walls, is modelled using Discrete Elements Method (DEM) with regard to the technological cycles of bunker filling and emptying. An experimental task was conducted on the site to identify the transport time of RFID tags that flowed together with the portions of ore they annotated. Empirical model of the transport system in the KGHM Lubin mine was parameterized with mean retention times obtained in DEM simulations in order to be compared with the RFID-tag experiment. The as-parameterized FlexSim simulation for one-chute bunker discharge variant yields tag transport times comparable with the experimental data. The results proved the reliable description of the ore transport time in the FlexSim model.

The ore quality at mining faces in the KGHM underground copper ore mines can be determined based on channel samples and block models built in the Datamine system. Unfortunately, even very accurate information regarding the quality of deposits at mining faces does not translate into the possibility of predicting the composition of feed to enrichment plants. The mixed ore from mining faces is cyclically loaded by trucks onto belt conveyors, which in turn convey it to shafts. When transported on the conveyors, mixed ore portions from many loading points form a divisional stream, which then goes to the main haulage conveyors where ore streams from various divisions are combined. The way of filling the bunkers, as well as ore flow temporary stoppages, changes the sequence of ore mixing and its arrival, which hinders the ability to track its quality. In the current study, radiofrequency identification (RFID) was proposed for tracking ore composition. A complementary method of ore quality prediction comes from simulating the tagged ore flow within the FlexSim software package. The discrete element method (DEM) of simulations, verified by experiments with RFID tags, can determine the ore flow through bunkers. Forecasts of ore feed composition for the next shift can be prepared with actual plans of mining division operations, the filling level of bunkers and the work plan of the transport system.

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A model of the transport system in a copper ore mine was prepared using FlexSim software and the simulations were performed for five days. Empirical parameters were applied to each item of the transport system in order for the ore transport times to correspond to the actual conditions. Both the class-and the loading point-specific haul truck courses were based on the five-day schedule. Mean inter-arrival times were modelled for haul trucks according to empirical histograms. The ore portions were discretized and their masses were based on haul truck load capacities. The simulations were performed for twelve variants covering the unavailability of different ore sources. The recorded statistics include ore provenience, lithology, Cu content and tag survival rate for RFID-tagged ore variants. The model represents the new way of solving the problem of ore mixing in a conveyor beltbased transport system. Adoption of the proposed scheme, will allow the enrichment plant managers to adjust the milling and crushing parameters to the lithology of the ore before it will leave the mine. The model allows to pinpoint the areas in the mine that produce certain demanded lithological factions and helps the managers to choose the most desirable pattern of the mining schedule and forecast the economical outcome.