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2020 International Conference on Ground Control in Mining, ICGCM 2020, Canonsburg, PA, USA, 28 Jul 2020 - 30 Jul 2020; International Journal of Mining Science and Technology 31(1), 9-13 (2021). doi:10.1016/j.ijmst.2020.12.005 special issue: "special issue on ground control in mining in 2020", Published by Elsevier, Amsterdam [u.a.]

International Journal of Mining Science and Technology 28(1), 79-83 (2018). doi:10.1016/j.ijmst.2017.10.004 special issue: "Special issue on ground control in mining in 2017 / Edited by Michel M. Murphy, Brijes Mishra, Kyle Perry, Heather Lawson", Published by Elsevier, Amsterdam [u.a.]

In the electrochemical deposition of copper on structured substrates, additives are commonly used as ingredients to refine the copper thin film properties. By means of cyclovoltametric (CV) measurements, we examine the process behavior of the additives PEG (polyethylene glycol) and chloride ions over a wide range of experimental parameters relevant for production-like conditions. In this plating process, additives practically are neither consumed in chemical reactions nor are they incorporated into the growing copper film. To understand the observed complex hysteresis behavior of the deposition current in CV scans, we have recently proposed a model which is able to qualitatively explain this behavior without supposing additive consumption. In the present study, we fit crucial parameters of this model from the experimental data to increase its predictive power. The quantitative agreement of performed simulations of CV scans with the measured scans demonstrates the validity of the proposed copper deposition model. Equipped with the determined parameter set, the model can help to optimize the copper plating process in industrial applications.

The use of new technologies makes it possible to increase automation in primary raw material extraction and contributes to meeting growing demands for higher productivity, reducing environmental impact and improving safety. One of the main technical challenges is the (increased) automation of navigation of mobile machines in underground mining environment. Until now, automated navigation in underground mines has been possible to a very limited extent. Current developments in the field of sensors for localisation and environment detection, algorithms for environment mapping and recognition, motion planning and the performance of computer and network technology open up potential for increasing the automation of navigation. The developments are available in principle, but have only been tested in individual applications or laboratory environments for practical use and have not been integrated into overall systems in a practical manner. The navigation of a mobile machine can be broken down into different tasks. These tasks include localisation, mapping, route planning, environment recognition, trajectory planning and vehicle motion control. For the navigation tasks, the characteristics of the underground mining environment are presented, which illustrate the technical challenges of underground navigation. The increase in automation is always linked to a reduction in human action. For the objective classification of the automation of technical systems, different levels of automation are defined. Existing levels of automation and levels of driving automation do not, however, reflect the complexity of underground navigation or the possibilities of including auxiliary systems for navigation automation. In order to classify the automation of under-ground navigation, new levels of navigation automation degrees are defined for the mining industry and are referred to as Level of Mine Navigation Automation (LoMNA) in accordance with the driving automation standards. These range in six levels from no automation (LoMNA 0) to full automation (LoMNA 5). Existing systems from production and research do not exceed the automation degree of conditional automation (LoMNA 3). This is due to the insufficient recognition of the environment and non-existent or inflexible reaction to a changing (dynamic) environment. Based on the tasks of navigation and LoMNA, a comprehensive system concept is being developed for the first time in analogy to the human information processing model. This is developed into a system architecture based on available sensors and in principle suitable, novel algorithms and implemented in a novel navigation sys-tem. The navigation system is evaluated in the underground environment of an active mining operation, in certain scenarios based on the tasks of navigation. Apart from the first-time use of some of the sensors and algorithms in the underground environment, novel developments include, in particular, the infrastructure-free, map-based, geo-referenced localisation, the way in which the detection of and dynamic reaction to obstacles is implemented, and the testing of route and trajectory planning in the underground environment. The navigation system developed within this thesis demonstrated a novel level of autonomous, flexible, dynamic navigation in the underground mining environment. It reaches the level of high automation (LoMNA 4) and can thus be classified higher than all known systems. In future, the application-oriented further development of system automation is to be seen in the context of a broader range of requirements from environmental conditions to becoming an innovation. Furthermore, the investigation of the possibilities of integrating perceptive intelligent infrastructure for navigation automation and system interoperability for process integration are to be presented as approaches for further research and development.

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019; Aachen 1 Online-Ressource (XXII, 245 Seiten) : Illustrationen, Diagramme (2019). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019, With an energy consumption of 10.4 % of the gross production value, the extraction of natural stones is one of the most energy-intensive industries in Germany. In-pit haulage is particularly critical in quarries, where those natural stones are extracted, as it is the most energy-intensive and cost-intensive process step. There are currently around 1,000 active quarries in Germany. In 90 % of these quarries, diesel-powered trucks are currently used for transportation. So far, more sustainable transport alternatives such as conveyor belts have only been used in exceptional cases. In this context, the aim of this thesis is to quantify energy and economic optimization potentials by the use of alternative transport techniques in German quarries. The analysis of the mining systematics and the process technology in quarries show that for an energetic and economical comparison of different transport techniques the process steps loading, transportation and primary crushing have to be considered. In order to implement these process steps, four different equipment combinations have to be examined. Besides the conventional transport with trucks in combination with a stationary primary crusher, the transport with belt conveyors in combination with a mobile primary crusher is considered. In addition, the combined transport of belt conveyors connected by a semi-mobile primary crusher with either trucks or wheel loaders in load & carry operation are investigated. The analysis of the relevant literature shows that application examples for belt conveyors in quarries have already been investigated. However, there are no studies with regard to an industry-related application potential. In addition, the general assessment of the basic framework conditions for the economically advantageous use of belt conveyors require high production tonnages, long transport distances and high lifting heights. Even the more optimistic estimates of a minimum production tonnage required for the economically advantageous use of belt conveyors of 1 million t/a rule out the use of belt conveyors in more than 90 % of German quarries. In order to identify general application potentials for the use of belt conveyors and to make them specifically assignable, a five-step cluster analytical technology comparison has been developed. In the first step, the required data is collected before it is structured in a cluster analysis. Eventually, specific reference quarries are defined. In the third step, the development of a calculation system results in the creation of a planning and calculation tool for a standardized technology comparison. The evaluation and interpretation of the calculation results is content of the fourth step. In the last step, the results are validated by the use of case studies. Based on the cluster characteristics pit size and pit depth, eleven clusters are defined, for each of which a reference quarry is defined by determining average values within a cluster. These reference quarries are used as application scenarios whose results can be transferred approximately to the other operations within a cluster. The development of a planning and calculation tool is based on the definition and presentation of the required calculation basis. By entering individual quarry parameters, the tool compares the transport techniques with regard to costs and takes into account the most economically advantageous equipment combination of each transport technique. In addition, the tool compares the energy requirements as well as the resulting greenhouse gas (GHG) emissions. For the evaluation two different scenarios are considered. In the “status quo” scenario, the transport techniques are compared for the most extreme level of a quarry. The second scenario “development model” is used to calculate average costs over the entire lifetime of a quarry. In a final sensitivity analysis, the influence of changing quarry parameters on the results is determined and general application restrictions for the economically advantageous use of belt conveyors are defined. The application of the planning and calculation tool to real quarries and the subsequent comparison with the actual conditions validates the tool and confirms the reliability of the determined results. The results of the work show that the use of belt conveyors could lead to economic advantages with a total savings potential of 63 million €/a in 70 % of German quarries, while compared to the use of trucks. This is paired with an industry-wide economic energy savings potential of 40 %. It also becomes apparent that economic advantages can be achieved from an annual production tonnage of 400,000 t/a onwards through the use of belt conveyors in quarries., Published by Aachen

The rising demands for automation systems continuously pose new challenges on the sensor systems. Due to the increasing capabilities of computer systems and their proportionally rising ability to process and aggregate data, the automation of manufacturing equipment is the long term goal since the 1990’s.Based on the developments of the industrial nations regarding Industry 4.0, the mining and heavy machinery industry have realized the potential of this vision. The digitization of the mine is the big subject of the future for many companies.This digitization is obviously multilayered, as one can immediately see from the many different and independent tasks in a modern mine: beginning with the winning, the transport and analysis of the material, the processing, the quality control, the loading and in parallel to all these tasks the repeated stacking and reclaiming of material. However, a central aspect of this automation is the knowledge of the surroundings of the machines to be automated. This inevitably leads to the task of mobile machinery positioning.In this thesis, a new positioning system, based on the UWB-Technology, is presented. The advantages of such a system can overcome several drawbacks of existing positioning systems in the industry.The basics of radio-based positioning, which are necessary for the understanding of positioning systems, are explained. The current state of the art of positioning systems is outlined and advantages and disadvantages are discussed. Furthermore, the state of art in research is outlined. After this, the basics of the UWB-Technology are explained and the development of the new positioning system is described. Several test measurements are shown in which the performance of the system is being tested and relevant installations of the system in real applications are described. Possible use-cases of the developed system are created. Improvements regarding (process) safety are described in which the new system can deliver an added value. Furthermore, an overview over the approval process of such a radio system in Germany, the EU and the USA is given, in order to help with the commercialization of this system. The thesis ends with a summary and an outlook on upcoming future developments.

Miners trapped underground at great depths can require long-lasting rescue missions of unknown dimensions. However, common tasks for today’s mine rescue teams mainly cover short-term fire-related incidents and first aid. Since European mining is going to greater depths than before, mine rescue needs innovative approaches for future challenges that will arise. Thus, this thesis develops a Mine Rescue Management (MRM) concept to increase preparedness for an efficient response to long-lasting entrapments.An analysis of current European mine rescue as well as a risk assessment regarding possible entrapment scenarios in modern mining operations give the scope of this thesis. A database of 56 major mine rescue missions has been compiled and a quantitative analysis proves the relevance of research. In the main part of this thesis, six single case studies are prepared with qualitative methods followed by a multiple case study analysis. Systematic lessons learned provide a first input for the MRM concept. Identified gaps and weaknesses in mine rescue are then met by a transfer of approved disaster management principles. Together, the two pillars – the case study results as well as the adapted disaster management principles – allow a definition of MRM. This management concept gives comprehensive instructions regarding planning, response, and learning.The tripartite MRM concept has the potential to improve the preparedness of today’s mine rescue for a complex mission to rescue miners trapped underground.

More than 100 years of hard-coal-mining in the lower Rhine area in the west of Germany were accompanied by subsidences of the surface. Existing today is a dense drainage system consisting of more than 270 pumping stations, 380 km of rivers, ditches, drains and dikes to avoid damages. The system is set in a 624 km2 large populated area and is operated by a water board, called LINEG. In conjunction with an integrated water resources management the system should be optimized, to reduce the on-going costs for pumping and maintenance.Planning should generally be holistic and long-term directed but what does that mean for this optimization process? There are plenty of interests, stakeholders, technical solutions, concepts and ideas, instruments, methods, tools, requirements, laws and planning factors. Hydraulic constructions require land and property and they are also impacting nature and landscape. There are also many approaches to improve the system; operational optimization, physical protection of objects, reparations, reduction of the total quantity of pumped water, constructional changes in the drainage system (e.g. deepening or rerouting), adjustment of the ground water table, multi-purpose usage of water, land and infrastructure and also organizational approaches, for example integration into spatial and city planning. Above all future changes, trends, predictions and the dealing with uncertainty should be considered (e. g. sustainable development, climate change but also technological, financial and social trends.This dissertation analyses these influences on this planning task especially for long-term considerations and shows related potentials opportunities and risks. It starts with a description of the characteristics of the planning area, looks at the operational costs and also decision-orientated costs like foreseeable investments and (not) internalized externalities as well as non-monetary aspects. It identifies and describes relevant influences in the planning environment and the planning process, as well as possible approaches for optimization. Finally the complex and dynamic problem of optimization is a decision problem of an (technical) investment planning, which requires an easy to handle support system and customized information.Based on these results a concept for planning, optimization and evaluation is designed. Among other principles it combines knowledge management, a geographical information system, model-based large-scale investigations, a dynamic cost comparison method and a sensitivity analysis into one bundle. In the end the system supports the water board to develop long-term and almost holistic masterplans.

The end of hard coal mining in the German Ruhr-District in 2018 will change the nature of the mining industry’s tasks. Even after the shutdown of the mines, the mining industry will continue to effect the region. Different measures of aftercare will have to be performed for a not foreseeable amount of time. Part of those measures is the pit dewatering, the cost of which largely depends on the level of mine water. Rising mine water can trigger different processes that potentially also lead to cost. In this work, all potentially triggered processes are identified, described and then examined in regard to their dependence on the level of mine water. The cost of the dependent processes is quantified and merged into a consolidated optimization model. This model may be used to determine the mine water level with the minimal cost overall.

In this doctoral thesis a detailed report about and a critical evaluation of the geothermal project "SuperC" and especially the well "RWTH-1" showed the wide range of a deep geothermal project run by a public administration. This mainly contained the technical, geological, economical and juristic tasks during the planning and realization stage. The use of a geothermal resource concerning the demand of resource protection in the German mining law was discussed. The necessity of a geological quality management before, during and after the drilling job was pointed out. First technical and geological project results were presented.The "SuperC"-project of RWTH Aachen University offers the unique possibility of demonstrating the use of renewable energies to a wide audience. The practical realization can be shown step by step. Due to its purposes as central service-center and as a kind of portal for the university the "SuperC" will be a location of communication where the use of geothermal energy will be transferred to a wide public for quite a long time. Furthermore there is a great chance to show the research activities of engineers and geoscientists in such an outstanding project and by this to support the development of geothermal energy in Germany and Europe.

W pracy przedstawiono analize dokladnosci prognozowania ruchow powierzchni i gorotworu wywolanych podziemna eksploatacja gornicza. Przeanalizowano czynniki, ktore maja negatywny wplyw na dokladnosc prognozowania oraz analize pomierzonych elementow ruchu gorotworu. Metodami geostatystycznymi przeanalizowano dane pomiarowe z polskiego okregu wydobycia miedzi pod katem ich przestrzennej zmiennosci. Glowna czesc pracy stanowi zaproponowana przez autora metoda symulacji elementow ruchu powierzchni wywolanych podziemna eksploatacja gornicza. Z jej pomoca zbadano w jaki sposob oddzialuja na przebieg prognozowanych elementow ruchu powierzchni niepewnosci zalozenia parametrow eksploatacji i parametrow gorotworu. Zaproponowana metoda, ktora mozna badac proces osiadania w ujeciu dynamicznym, pozwala na obliczenie najbardziej prawdopodobnego przebiegu elementu ruchu powierzchni wraz z obszarem zaufania prognozy oraz prawdopodobieñstwem przekroczenia dowolnie zalozonej wartosci krytycznej.