Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie Number 03/2022

The method of excavation and the type of ore transport used make it possible to divide mineral extraction technologies into: continuous, cyclic and mixed. In opencast mining, cyclic technologies are leading the way. Automated systems are being developed for its needs. The first group includes collision detection systems, the second group semi-automatic systems in which most operations are controlled by a human and only some are performed automatically, and the third group remote control systems. In addition to the above groups, fully automatic and autonomous systems are being developed, in which the operator acts as a supervisory factor, intervening only in emergency situations. Eliminating the weakest link in vehicle operation - the human being - increases the system's availability to 24 h/d all year round and improves crew safety. In addition, the entire planning and logistics part is taken over by artificial intelligence systems. This allows constant monitoring of the technical condition of the equipment and its full utilisation, while optimising fuel consumption. Among the world leaders in this field are: Komatsu, Volvo, Scania and Kamaz, which is just starting out in this segment. A review of the solutions they develop convinces us that they mostly use suitably modified, mass-produced trucks, which reduces the costs of implementing the systems, resulting, among other things, from the need to provide redundant data transmission systems and separated ICT networks, preventing outside interference with the system. In addition to their provision, Polish regulations for opencast mines to enable the use of autonomous cyclic transport systems should also oblige, inter alia, the use of at least two independent teletransmission lines for real-time exchange of information between vehicles and the dispatcher, and the marking of the area of the mine with signs informing of the work of autonomous vehicles and the prohibition of the movement of people on haul roads during their work.

The use of an allflux AFX 1500 fluidised bed sorter at the Bielinek mine, which purifies and sorts fine sand fractions in a single process, as well as the automated sorting process at the new processing plant, streamlines the sand production process and improves the safety of machinery and equipment. The advantage of using modern sand production methods is the ability to create aggregate compositions requested by customers for appropriate applications and to improve the quality of the aggregate by reducing the content of impurities and limiting the loss of fine fractions of sorted sand, which are necessary for the production of sand and gravel mixes allowing better grain compression and optimising cement consumption for concrete production.

Floating excavators are becoming increasingly important in the extraction of natural aggregates. It involves the need to ensure the stability of permanent slopes (banks) of created water bodies. The preservation of stable slopes requires that they be properly formed already during the exploitation phase, as the subsequent "slope correction" involves additional costs and serious technical problems. When approaching the limits of the planned mining, there is therefore a need to run slopes with different parameters than the working ones. For this reason, excavator operators and supervisors should be able to assess the position of the excavating body (immersion depth and distance from the protective strip on the surface), in relation to the established limits of exploitation. Most floating excavators have the ability to control the dip depth of the excavating body, but do not have the equipment to measure its position relative to the above-water part of the slope being excavated. In practice, rangefinders are best suited for this purpose. The correctness of the measurements made with them, however, requires that they be carried out parallel to the water surface and perpendicular to the edge of the target permanent slope, preferably always from a selected measuring point on the excavator's platform.