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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 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.