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Abstract

Significant quantities of coal sludge are created during the coal enrichment processes in the mechanical processing plants of hard coal mines (waste group 01). These are the smallest grain classes with a grain size below 1 mm, in which the classes below 0.035 mm constitute up to 60% of their composition and the heat of combustion is at the level of 10 MJ/kg. The high moisture of coal sludge is characteristic, which after dewatering on filter presses reaches the value of 16–28% (Wtot r) (archival paper PG SILESIA). The fine-grained nature and high moisture of the material cause great difficulties at the stage of transport, loading and unloading of the material. The paper presents the results of pelletizing (granulating) grinding of coal sludge by itself and the piling of coal sludge with additional material, which is to improve the sludge energy properties. The piling process itself is primarily intended to improve transport possibilities. Initial tests have been undertaken to show changes in parameters by preparing coal sludge mixtures (PG SILESIA) with lignite coal dusts (LEAG). The process of piling sludge and their mixtures on an AGH laboratory vibratory grinder construction was carried out. As a result of the tests, it can be concluded that all mixtures are susceptible to granulation. This process undoubtedly broadens the transport possibilities of the material. The grain composition of the obtained material after granulation is satisfactory. Up to 2 to 20 mm granules make up 90–95% of the product weight. The strength of the fresh pellets is satisfactory and comparable for all mixtures. Fresh lumps subjected to a test for discharges from a height of 700 mm can withstand from 7 to 14 discharges. The strength of the pellets after longer seasoning, from the height of 500 mm, shows different values for the analyzed samples. The values obtained for hard coal sludge and their blends with brown coal dust are at the level from 4 to 5 discharges. The strength obtained is sufficient to determine the possibility of their transport. At this stage of the work it can be stated that the addition of coal dust from lignite does not cause the deterioration of the material’s strength with respect to clean coal sludge. Therefore, there is no negative impact on the transportability of the granulated material. As a result of mixing with coal dusts, it is possible to increase their energy value (Klojzy-Karczmarczyk at al. 2018). The cost analysis of the analyzed project was not carried out.
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Abstract

Caving in the excavation of mining galleries is a dangerous phenomenon, resulting in a threat to the health and life of humans, technological difficulties (transport, ventilation, etc.) and economic losses. Mining galleries list: design errors, runtime errors, errors and random causes among the causes of the caving occurring in recent periods in the excavation of underground coal mines. Examples in the recent period of caving in the excavation of mining galleries in coal mines indicated that one of the main causes of the situation was the loss of capacity and double timber technical wear caused by the corrosion of the profile. In practice, the caving that occur as a result of the technical wear can be divided into the breaking arc of a roof – bar, the loss of stability of one of the heading walls and a total heading collapse. On the basis of the carried out analysis of these cases, guidelines were proposed for improving the safe operation of the workings. The improvement of support stability may be achieved by applying additional supports, stabilizing the structure by bolting the support sets or by introducing a fiber-reinforced concrete coating with injection into the rock mass. Examples of caving occurring in the excavation, for which the preparatory selection of support does not match the geological-mining conditions, were also presented. The summary indicated the importance of diagnostics roadway in the safe and efficient conduct of mining that should be covered by the operational rules, and their scope and frequency should be adapted to the rank of the occurrence of hazard and support construction.
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Abstract

A subject of the paper Substantive Declension in Slavic Linguistic Atlas is based on an extensive field research of the Dialects of all Slavic languages. The territory of the research is delimited by the international Slavistic project Slavic Linguistic Atlas the database of which is formed by answers to 3400 questions within 853 localities of the overall Slavic territory. However, not all the forms of all the substantive paradigms are presented, but only the selected representative phenomena testifying to the natural constitutive processes of the national languages in connection with the phonetic changes proving the specifi c character of the linguistic development under the infl uence of a genetically homogeneous or heterogeneous environment and testifying to linguistic changes as results of intercultural, interlingual and probably also inter-confessional infl uences. The final part of the publication is oriented upon the constitutive processes of substantive declination in the Slavic macro-areas (South-Slavic, West-Slavic, and East-Slavic – and within them also in the particular Slavic languages) from the point of view of “otherness” and “foreignness”, i.e. from the point of view of the original and non-original grammatical endings in the particular declension types. The genuine basis of the transgression from the original domestic elements to the new ones gets manifested not only within the adaptation processes of the lexical level, but its basis is hidden in the long-term stabilization processes, in systemic changes by which the inner structure of the language, the area of the distribution of changes, and their impact upon the typological substance of the language are modified. By its interpretative character, the paper The Interpretation of Substantive Declension in Slavic Languages aims at integrating the genetic, areal as well as typological aspects of the investigated domain.
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