Impact of the Winding Angle of the Auger Blade on the Loading Process With Milling Auger Drums

This publication addresses the impact of selected design parameters of milling auger cutting drums on the loading process, and above all the winding angle of the auger blade. The loading process is often referred to as an auxiliary process because the milling process is considered to be the dominant throughout the work of the cutting drum. The correct determination of the relationship between the mining process and the loading process allows to understand how the individual design and kinematic parameters of the mining drums and the mining machine on which they are installed affect each other. The publication discusses the problem of loading with milling cutting drums and ways to increase its efficiency. The research results of the loading process have been presented, affecting the efficiency of this process in the aspect of various angles of inclination of the auger blades. Based on the tests, conclusions have been formulated that allow for the possible selection of an appropriate winding angle for the auger blade, depending on the granulation of spoil.

Key Performance Indicators (KPIs) as a Tool to Improve Product Quality

The literature includes a wide selection and distribution of performance indicators to be used in different areas of the company. The paper highlights the Key Performance Indicators (KPIs) as those that are the most universal and allow the control of intended targets in different areas of the enterprise. KPIs are financial and non-financial process measures used to assess the degree of achievement with regard to strategic and operational objectives in a company. They are also used to measure the effectiveness of all activities undertaken in an organizational unit. The paper presents the possibility of using KPIs to improve the quality of manufactured products, by analyzing the trend of selected indicators. This analysis gave an impulse to undertake improvement actions in the company consisting in the use of quality management method – in this case 5 WHY leading to the initiation of preventive and corrective actions in the occurrence of defective products.

Analysis of Gas-Geodynamic Phenomena During the Preparatory and Mining Works in Seam 358/1 at KWK “Budryk”

The nature of gas-geodynamic phenomena is so complicated and unpredictable that it forces the necessity of continuous search for new principles of identifying the outburst threat and ongoing monitoring of this threat with view of current conditions in the mine. After the incidents in JSW S.A, the mines carrying out works in seams threatened with outbursts, upon their own initiative introduced additional rigours and increased the frequency of measurements and tests regardless of the existing legal requirements. Incidents that have taken place in KWK “Budryk” in recent years show how important is continuous verification of knowledge related to the forecasting of the outburst threat on the basis of ongoing observations of works. The local occurrence of a zone characterized by high methane-bearing capacity in the coal seam, even after taking preventive measures and introducing additional rigorous did not allow for the complete elimination of gas-geodynamic phenomena and avoidance of danger to employed people.

Functioning Efficiency of the Central Air-Conditioning System on the Selected Example

One of the particularly significant threats during exploitation is the climatic threat, which is associated with an increase in the overall costs that are allocated to combating it. The rise in the virgin temperature of the rock mass by 1oC increases the demand for the required cooling capacity to be taken from the air. The publication assesses the effectiveness of the air-conditioning installation by testing its operation on a selected example. The assessment of the efficiency of the air-conditioning installation for a selected hard coal mine showed that none of the five tested coolers achieved the maximum assumed rated power. The use of total power (7.5 MW) in mining excavations was less than 50% and amounted to η = 0.472%. The research showed that the main reason for obtaining low cooling parameters is the inability to locate them in the place of the highest air temperatures. The other problem is an insufficient airflow rate of cooling water supplied to the coolers at too high temperature. The above considerations indicated that the cooling power from built-in air- conditioning systems is not properly and effectively used. Improving the efficiency of its functioning is possible by proceeding research that will eliminate the above factors and by using air conditioning equipment, taking into account the periodic audit of their work to reduce electricity consumption.

Subsidies as Financing Opportunities – the Development of Renewable Energy Sources in Poland

As Poland is considered a coal country, renewable energy resources still do not have a significant share in energy production. Further, 14% contribution of renewable energy to total primary energy production in 2020 is endangered. Thus, in order to speed up with renewable energy sources new actions should be stimulated. The aim of the article is to describe the most popular renewable energy installations in Poland and further to search for a case study indicating that an investment in renewable sources is profitable without financial support. The results indicate that prior literature does not present any analysis of profitable renewable energy investment without financial support. It states the need for regulators to implement additional financial support not only on the European Union level but also on the national one.

Economic Assessment of Methods of Coal and Gas Outburst Prevention in the Extraction of Coalfaces

In this paper, the authors focused on the assessment of the individual methods to prevent coal and gas outbursts. The first part deals with a characteristic of this anomalous phenomenon and some basic methods of coal and gas outburst prevention. The second part presents the economic assessment of the costs necessary to ensure the possible prevention methods in the coalface 080 211 in the locality of the Paskov Mine, Mining Plant 3, OKD as, Czech Republic. In this coalface, a simulation method was used for calculating costs for the drift length of 100 m for the use of various prevention methods (irrigation, relief boreholes, relief blasting). The results show the cost of preventive measures during mining intended to eliminate and protect against the formation of coal and gas outbursts. The measures are compared applying the principle of the decision analysis. Four criteria are used for the mutual comparison of the methods (costs, effort, efficiency, time consumption). The comparison has shown that the optimal method to prevent coal and gas outbursts is irrigation.

Information Value of the Segment Reporting in the Polish Energy Sector

Conventional energy sources dominate in the Polish energy sector, which is a huge risk to meeting environmental protection requirements. Polish energy companies are facing challenges related to meeting the requirements of the European Union and the National Energy Policy. The paper attempts to answer the question whether the ongoing discussion on the future of the energy sector, dealing with such issues as development of renewable energy sources is reflected in the annual financial reports of companies listed on the Warsaw Stock Exchange and covered by the WIG_ENERGY index. This study contributes to the extant literature on financial disclosures in several ways. First, the examination of compliance of segment reporting of selected companies listed on the Polish stock exchange with International Reporting Standards (IFRS) was carried out (particularly IFRS 8 – Operating Segments). Second, the information value of disclosures for investors in the energy industry was assessed. The empirical part was preceded by a description of segment reporting principles in accordance with IFRS 8 and the summary of challenges facing the energy sector in Poland.

Conical Pick Production Process

One of the basic methods of mechanical rock mining is cutting, which faces increasingly difficult working conditions. Despite the rapid development of machines used in underground and opencast mining as well as in tunnel building, construction industry and road engineering, the problem of insufficient durability of mining tools remains unsolved. In addition to drilling and, to a lesser extent, planing, cutting provides a huge market for tools. Currently, the process of cutting is mainly based on conical picks. The cutterheads of cutting machines are equipped with several dozen, and frequently – more than one hundred conical picks, which, due to their workability and abrasiveness, sometimes work only a few hours. There is a market demand for over two hundred models of conical picks. This is due to the huge variety of shapes and sizes of picks as well as the methods of their mounting in the holder. The article briefly presents various solutions of conical picks, their construction, methods of protection, dimensions and materials used. Next, based on materials produced by ZWM Carbonex, the classic method of their manufacture using the turning technology has been described. The authors have also presented briefly the use of die forging for the large-scale production of picks, applied by Górnicza Fabryka Narzędzi Sp. z o.o.

Geostatistical Methods as a Tool Supporting Revitalization of Industrially Degraded and Post-Mining Areas

Post-industrial and post-mining areas have often been under strong anthropogenic pressure for a long time. As a result, such areas, after the ending of industrial activity require taking steps to revitalize them. It may cover many elements of the natural or urban environment, such as water, soil, vegetated areas, urban development etc. To carry out revitalization, it is necessary to determine the initial state of such areas, often using selected chemical, geophysical or ecological. After that it is also important to properly monitor the state of such areas to assess the progress of the revitalization process. For this purpose a variety of change detection technics were developed. Post-industrial areas are very often characterized by a large extent, are difficult to access, have complicated land cover. For this reason, it is particularly important to choose appropriate methods to assess the degree of pollution of such areas. Such methods should be as economical as possible and time-effective. A very desirable feature of such methods is that they should allow a quick assessment of the entire area. Geostatistics supplemented by modern remote sensing can be effective for this purpose. Nowadays, using remote sensing, it is possible to gather information simultaneously from the entire, even vast area, with high spatial, spectral and temporal resolution. Geostatistics in turn provides many tools that are able to enable rapid analysis and inference based on even very complicated often scarce spatial data sets obtained from ground measurement and satellite observations. The goal of the article was to present selected results obtained using geostatistical methods also related to remote sensing, which may be helpful for decision makers in revitalizing post-industrial and post-mining areas. The results described in this paper were based mostly on the previous studies, carried out by authors.

Rehabilitation of Post-Mining Areas in the Bohumin City Area (Czech Republic). Case Study

Rehabilitation of post-industrial areas involves many areas. The area after hard coal mines, requires many specific actions and funds in order to eliminate any remnants of the former infrastructure that is located in this area. The area of Upper Silesia, which includes areas on both the Polish and Czech borders, belongs to the area where the process of underground hard coal mining is being extinguished. As a result of the completion of mining works, the mine areas and adjacent sites begin to undergo transformations. Thus, the landscape of this area changes, various types of land, residential buildings and roads are destroyed. The activities related to restoring the utility value to degraded areas should be carried out consistently, primarily from their inhabitants’ perspective. The rehabilitation of post-mining area and its proper management can bring great benefits to the city and its inhabitants in the future. The publication presents a proposal for land development solutions for the former hard coal mine in Bohumin, Vrbice district in the Czech Republic.