A comprehensive scientific approach will facilitate rationalization processes and minimization of mine liquidation costs. The study, based on a statistical analysis of liquidation processes in 19 mining plants from 2015 to 2023, proposes a method for preliminary estimation of costs and time of potential liquidation of hard coal mines. The method can be used for preliminary estimation of mine liquidation costs and as a cost management tool. The method does not refer directly to the liquidation processes used in SRK S.A. therefore, it can also be used by any entity in mine liquidation process as a comparative tool for detailed and multi-criteria estimation of the costs of planned mine liquidation.

Statistical data on occupational diseases recorded by the Institute of Occupational Medicine in Lodz, Poland, indicate a renewed increase in the number of cases of pneumoconiosis in Poland in recent years, especially in the PKD section of mining and quarrying industries. At the same time, in 2018 as a result of the implementation of directives of the European Parliament and the Council of the European Union, the changes were introduced to the Polish legislation in the area of protection of workers from the risk of exposure to carcinogenic or mutagenic agents related to the respirable fraction of crystalline silica found, among others, in mine dust. As a result of these solutions, since 2020 we have seen a spike in the number of miners employed in conditions of risk of carcinogenic dust. These facts indicate that despite the wide measurement of harmful factors in coal mines, the effectiveness of preventive measures taken does not bring tangible benefits, and OSH services have problems with the proper assessment of industrial dust hazards at workplaces. In the article, based on surveys, diagnostic (health) tests of workers and verification of the risk assessment methods used, the authors try to point out the most common mistakes made in estimating the level of risk associated with exposure to industrial dust.

The paper focuses on experimental monitoring of tightening and floating of the belt at controlled loading of belt gear. In general, the belt gear is referred to as friction gear in practice the primary function of which is to transfer the performance as a consequence of frictional forces occurring between a driven belt pulley, a driving belt pulley and a flexible element. In experimental measurements, the flexible element is represented by a V-belt. The main advantages of the belt gears are peripheral speed, flexible engagement, silent running, vibration absorption and their price. Standard operation of the belt gear requires correct belt tightening which is achieved by movement of a pulley and a tension roll. At the same time, the belt tightening can be achieved by changing the spacing of the shaft axes used in experiments. In the case of belt gears use, specific principles must be observed. The principles include tightening of the belt with particular force which represents, in fact, primary condition of transmission of motion and force. At rest, the tension of both belt parts is identical. Complex analysis of belt gears was followed by experimental measurements on the stands designed for testing and monitoring of belt gears. For the purposes of monitoring of the belt floating there was a system designed which used a high precision sensor to measure distance between the belt and the sensor. At the same time, a device designed to determine the belt tightening was used as well. All measurements were analysed and collected data and facts were used to determine dependencies possible to be applied when the monitored parameters are evaluated. The results of experimental monitoring of the selected parameters at controlled loading of the belt gear can be useful in practice for designing, checking and maintenance operations.

The article presents a study of the dynamic forces occurring in the chain of a rescue scraper conveyor during its steady operation. It describes the characteristics of the test stand in the form of a scraper conveyor for investigating dynamic forces in the chain, moreover, the results of these tests are presented. Based on the values obtained during the dynamic tests, the characteristic parameters of the above mentioned measurements were determined.

Based on the results of tests of the monorail transport system using suspended diesel locomotives with traditional transport beams and with the use of an innovative system of transport beams for the delivery of heavy loads, it was found that to reduce the dynamics of the load to the elements of the suspended route segments fastened to the arches of the arch support, it is beneficial to use the proposed an innovative technical solution that increases the reliability of the route catches to the support arches, which is important when transporting heavy loads. The new solution significantly reduces the dynamic loads to the route catches to the support arches by redistributing the load over a greater number of sections of the suspended monorail route. It has been proven that during the period of intensification of preparatory work, these technical solutions make it possible to keep to the timely preparation of new mining pillars and are perceived as a promising direction for improving the existing transport system for the mines of the region and ensuring the operational parameters of mining transport equipment at a high technical level in the specific conditions of the mines of Western Donbass.

Waste Electrical and Electronic Equipment (WEEE) that contains neodymium magnets (NdFeB) has the potential to serve as a valuable source of elements, including critical ones. These magnets contain Rare Earth Elements (REEs) like Neodymium, Dysprosium, and Praseodymium.  A noteworthy method of recycling REEs involves the magnet-to-magnet process, wherein the NdFeB alloy is separated from WEEE and directly reused in the production of new products, specifically new NdFeB magnets. The initial step in this recycling process involves disintegration, a procedure aimed at reducing and segregating the materials within the WEEE. The conventional process of disintegrating WEEE for recycling faces challenges due to the presence of magnetic materials, making it ineffective with existing equipment. To address this, a specialized device called a disintegrator, using counter-rotating cutting shafts, has been developed for efficient shredding of WEEE containing NdFeB. The goal of the research is to develop a prototype shredder to effectively recover valuable metals, including REEs, from WEEE. Specific sub-objectives include motor and gearbox selection, shaft bearings selection, gear design, and cutting blades design. The work involved calculations and 3D modelling of the disintegrator components using Autodesk Inventor 2020 software.