Following an unexpected event in an underground mine, it is important to know the state of the mine immediately to manage the situation effectively. Particularly when part or the whole mine is inaccessible, remotely and quickly ascertaining the ventilation status is one of the pieces of essential information that can help mine personnel and rescue teams make decisions. This study developed a methodology that uses tracer gas techniques and CFD modeling to analyze underground mine ventilation system status remotely. After an unanticipated event that has damaged ventilation controls, the first step of the methodology is to assess and estimate the level of the damage and the possible ventilation changes based on the available information. Then CFD models will be built to model the normal ventilation status before the event, as well as possible ventilation damage scenarios. At the same time, tracer gas tests will be designed and performed on-site. Tracer gas will be released at a designated location with constant or transient release techniques. Gas samples will be collected at other locations and analyzed using Gas Chromatography (GC). Finally, through comparing the CFD simulated results and the tracer on-site test results, the general characterization of the ventilation system can be determined. A review of CFD applications in mining engineering is provided in the beginning of this dissertation. The basic principles of CFD are reviewed and six turbulence models commonly used are discussed with some examples of their application and guidelines on choosing an appropriate turbulence model. General modeling procedures are also provided with particular emphasis on conducting a mesh independence study and different validation methods, further improving the accuracy of a model. CFD applications in mining engineering research and design areas are reviewed, which illustrate the success of CFD and highlight challenging issues. Experiments were conducted both in the laboratory and on-site. These experiments showed that the developed methodology is feasible for characterizing underground ventilation systems remotely. Limitations of the study are also addressed. For example, the CFD model requires detailed ventilation survey data for an accurate CFD modeling and takes much longer time compared to network modeling. Some common problems encountered when using tracer gases in underground mines are discussed based on previously completed laboratory and field experiments, which include tracer release methods, sampling and analysis techniques. Additionally, the use of CFD to optimize the design of tracer gas experiments is also presented. Finally, guidelines and recommendations are provided on the use of tracer gases in the characterization of underground mine ventilation networks. / Ph. D.

The safety of miners is of interest to all countries. In the event of a coal mine disaster, how to locate the miners remains the biggest and most urgent issue. The aim of this study is to propose a precise positioning method for underground mine environments to a low cost and with acceptable accuracy. During the research work, in-depth learning and analysis of current geolocation methods for indoor areas have been carried out: advantages, disadvantages and the level of suitability of each method for mine environment have been presented. A layered two-step Hidden Markov Model has been proposed to simulate human walking in underground mine environments and an improved Viterbi algorithm suitable for the model has been implemented. The result of the positioning accuracy is quite satisfying compared to other positioning methods in the same category. A small modification to the proposed model has been illustrated in the future work which makes it more suitable for different situations rather than that limited by assumptions. The proposed positioning method can be claimed to be quite suitable for underground mine environments to a low cost and with acceptable accuracy.

This study investigates the possibilities of using mesh networking in underground mines. It is of utmost importance to investigate the safety and ethical aspects of implementing new systems in mines, namely mesh networking. Simulations and calculations have been made to analyze and arrive at findings of update intervals for a potential mesh network. Semi-structured interviews have been conducted with responsible staff at underground mine sites, and this study has followed a qualitative approach. Theoretical concepts such as Locatilization infrastructures in underground mines and Personal security and work environment laws in underground mines have been analyzed and discussed in relation to empirical results using thematic analysis. Due to the importance of safety aspects of emergency notifications and real time location tracking, our findings show that mesh networks may not be a viable replacement for a fully connected network in a mine network infrastructure. However, mesh networks or hybrid networks may be a more viable way to improve safety for certain mines that do not have an existing network infrastructure, or as a temporary extension to a fully connected network infrastructure.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Mining activities around the world are undergoing constant change and modernization owing to technological and scientific advancements. Consequently, there are frequent proposals to streamline and enhance processes in mining operations. This study deals with ore transportation in mechanized mining units and aims to optimize fleet management using the Lean Six Sigma methodology to obtain a model in this specific process. The proposed method was implemented using a Lean Six Sigma instrument known as DMAIC (Define, Measure, Analyze, Improve, and Control). The case study was applied to an underground mine located in the Huancavelica region, Peru. The simulation showed that 24% of the time in the ore transport cycle is un-productive time and the improvement potential time represents 53% of the transportation process time.

En la presente tesis se estudia la aplicación de las herramientas del Lean Six Sigma en el desarrollo de una metodología para la evaluación de proyectos auríferos de vetas angostas en el norte del Perú. Dichas herramientas responden a controles de calidad, tiempo y procesos, los cuales tienen como finalidad el desarrollo de la evaluación económica del Proyecto Trinidad. La propuesta se desarrolló, en primer lugar, con un análisis inicial del proyecto Trinidad con la finalidad de generar estrategias, dicha actividad consta de tres partes: matriz inicial del proyecto, House of Quality y análisis FODA. En segundo lugar, se determinaron las mermas operativas y se diseñó el mapa de flujo de procesos mediante la herramienta BPM (Business Process Management). En tercer lugar, se estableció un control en los tiempos para los procesos identificados para la evaluación del proyecto, mediante la herramienta JIT (Just In Time), es aquí donde se determina los plazos para las actividades involucradas, desde gestión de información hasta cálculo de recursos, método y secuenciamiento de minado y determinación de costos. Finalmente, se analiza el valor del proyecto y el riesgo que conlleva su ejecución. Mediante indicadores como VAN y TIR calculados a partir de la identificación del CAPEX, OPEX y el flujo de caja obtenido del valor teórico de los recursos y los costos operativos. / This thesis studies the application of Lean Six Sigma tools in the development of a methodology for evaluating narrow vein gold projects in northern Peru. Such tools respond to quality, time and process controls, which are intended to develop the economic evaluation of the Trinidad Project. The proposal was developed, firstly, with an initial analysis of the Trinidad project in order to generate strategies, said activity consists of three parts: initial project matrix, House of Quality and SWOT analysis. Secondly, operational losses were determined and the process flow map was designed using the BPM (Business Process Management) tool. Third, a control was established in the times for the processes identified for the evaluation of the project, through the JIT (Just In Time) tool, it is here where the deadlines for the activities involved are determined, from information management to calculation of resources, mining method and sequencing and cost determination. Finally, the value of the project and the risk involved in its execution are analyzed. Through indicators such as NPV and IRR calculated from the identification of CAPEX, OPEX and the cash flow obtained from the theoretical value of resources and operating costs. / Tesis