Witold Kawalec

Study on Tracking the Mined Ore Compound with the Use of Process Analytic Technology Tags

The growing need of reducing the use of raw materials and energy in the chain of supplying goods draws the attention to all aspects of the most energy intensive processes like mining and processing of metal ore. Processing of raw materials strongly depends on their parameters, hence the more accurate identification of them should improve the process efficiency. The Process Analytic Technology with information carrying tags (pellets), annotating transported or processed raw material – is investigated within the DISIRE project. The application of DISIRE PAT for non-ferrous minerals processing is dealt with the copper producer KGHM S.A. The ore exploited in its underground mines in Poland is among the most difficult for processing. The ore compound is recognized in-situ – in mining faces. On the way to processing plants down the transportation system consisting of belt conveyors and ore bunkers, the portions of ore from numerous mining faces are converted into an unknown mixture. The study of PAT tags implementation to assign the conveyed ore with the relevant information to recognize the mixed ore compound is presented.

Application of compound Poisson process for modelling of ore flow in a belt conveyor system with cyclic loading

Abstract This paper deals with the analysis of the random process of cyclic loading of a mining belt conveyor with portions of ore discharged by loaders or trucks. Such transfer of transported ore from a cyclic to a continuous transport is typical for the specific mining operations implemented in the underground copper ore mines with room and pillar mining. The conveyors in such systems are usually significantly oversized in order to match the peak loads of cumulated discharges of ore hauled from mining fields by loaders. Therefore, the actual loadings that occur in the mining transportation systems need to be analysed to provide the data for more accurate design and control of belt conveyors. The large data-set of actual loadings of the belt conveyors has been used for the stochastic modelling of the analysed process. The compound Poisson process has been proposed as mathematical tool to analyse/describe properties of ore flow. The discussion of the chosen distribution functions and results of the fitted model simulations compared with the examined measurement data are presented. In this paper, the case of a belt conveyor loaded only by a single feeding point where loaders are randomly discharged have been analysed. More complex cases (several loading points, mixed ore supply from cyclic and continuous ore mass flow from preceding conveyors or ore bunkers) are under investigation and will be presented in the future.

Autocorrelation Analysis of Cu Content in Ore Streams in One of KGHM Polska Miedż S.A. Mines

Information about ore quality along its route from its source – the deposit, through long and complicated belt conveyor system till processing plant is not available in KGHM Polska Miedz on a daily basis. There were only few papers which analyzed variability of Cu content in feed to processing plant, on the transfer conveyor linking two mines and on the selected sectional conveyors. There were no such analysis regarding variation of ore lithological compositions. Such knowledge should improve metal recovery and reduce energy in processing plant by adjustment of milling and ore beneficiation parameters to known in advance copper ore quality data. Lack of data about ore composition prompted authors to analyze autocorrelations of Cu content time series in ore streams on the section and transfer conveyors as well as in the feed to processing plant. Determined differences in range of significant autocorrelations in ACF and PACF in different places along belt conveyor route have been explained by increasing difficulties in changing the average content of copper in ore coming from the growing area and a range of routes of loading machinery and face advance in comparison to range of directional semivariogram. The planned DISIRE experiment with application of Process Analyser Technology (PAT) sensors (containing ore information pellets), dropped into the transported ore streams and simulations of real flow of ore stream should show possibility to predict ore quality in advance to give enough time for necessary adjustments.

Random Loading of Blasted Ore with Regard to Spatial Variations of Its Actual Lithological Compound

The simulation model of the mine transportation system with regard to actual parameters of haul truck inter-arrival times was built in FlexSim. Haul trucks classified by their payload were sampling the rock material from corresponding mining faces. Two main simulation variants (V1 and V2) with a constant overall or mining face specific copper content and lithology were analyzed. The new algorithm was developed, based on the random sampling of lithologic factions from the muck pile by haul trucks. The variant V2b illustrates the interesting feature of this algorithm, when first more material from the bottom layer of the mined seam was drawn, causing the depletion of its deposit in the subsequent haul truck courses. The study demonstrated that both approaches can be used interchangeably to simulate the economic outcome of the metal production on the hourly basis. The difference between V1 and V2 variants in the total amount of copper produced after full simulation cycle changes linearly with the amount initially blasted rock mass declared in the V2 variant. The algorithm allows to choose the maximum amount of rocks to be blasted that can be delivered to the OEP in a given time.

Application of the Discrete Element Method (DEM) for Simulation of the Ore Flow Inside the Shaft Ore Bunker in the Underground Copper Ore Mine

Identification of the stream of transported mine output has a great importance for the effectiveness of ore processing and for the control of mining operations. The above fact entails the growing importance of various types of scanners and on-line sensors which serve to determine the measurable parameters of a random sample and to use this information as a basis for the classification of the whole stream of mine output. An alternative method consists in effective processing of large data sets (the “big data” technology), i.e. in combining the previously generated information on the deposit (geological data), information on the locations of currently operated mine fields (mining data), and information on the flow of the stream of mined ore in the underground transportation system. The flow of mine ore is modeled with the use of simulation methods, whose reliability largely depends on how accurately a particular transportation system and its operation are reproduced in the model. Particular attention must be paid to accurate modeling of ore behavior in the nodes of the transportation system, i.e. in the bunkers. The bunkers, apart from serving a retaining function, also effect the averaging of ore parameters, as the portions of mined material subsequently added to the bunker change their position and mix. Modeling the behavior of mined ore inside the bunker is the object of tests performed with the use of Discrete Element Method (DEM).