The study included bituminous coal seams (30 samples coal from the Bogdanka and Chełm deposits)

of the Lublin Formation, the most coal-bearing strata in the best developed and recognized in

terms of mining parts of the Lublin Coal Basin in Poland. High phosphorus concentrations in coal of

the Lublin Formation were found (1375 g/Mg) as well as P2O5 in coal ash (2.267 wt%). The phosphorus

contents in coal and coal ash from the 385 and 391 coal seams in the area of the Lubelski Coal Bogdanka

Mine and in the area of its SE neighbor is the highest (max. 2.644 wt. % in coal and 6.055 wt. %

of P2O5 in coal ash). It has been shown that mineral matter effectively affects phosphorus contents

in coal and coal ash. At the same time, phosphate minerals (probably apatite and crandallite) present

in kaolinite aggregates of tonsteins contain the most of phosphorus and have the greatest impact on

the average P content in the 382, 385, 387, and 391. The secondary source of phosphorus in these

coal seams and main source of phosphorus in these coal deposits that do not contain mineral matter

of pyroclastic origin (378, 389, 394) may be clay minerals, which absorbed phosphorus compounds

derived from organic matter released during coalification. Phosphorus-rich ash from the combustion

of the Lublin Formation coal tend to be environmentally beneficial to the environment and also useful

for improving the soil quality. Due to the low degree of coalification and high content of phosphorus

in coal, this coals of little use for coking.

The new boreholes drilled between 2009 and 2012 enabled a detailed exploration of the profile of the Kraków sandstone series in the Dąb area between the “Sobieski” and “Janina” mining plants, USCB (Upper Silesian Coal Basin). The core from the No. 111. bituminous coal seam was selected for further analysis. 30 intervals corresponding to the defined lithotypes were separated in the seam with a thickness of 116.8 cm. The thickness of lithotypes ranges from 10 mm to 89 mm. A microprofile of the examined seam was made using the modified method of determining microlithotypes. A quantitative determination of the maceral composition was performed for each interval corresponding to the separated lithotypes. This allowed petrographic and facies characteristics of the seam to be determined. Its lower part is dominated by lithotypes with a large share of bright coal – vitrain coal. This section of the profile was formed under conditions of a strongly flooded wet forest swamp. In the upper section of the seam, a higher macroscopic share of dull coal – durain was observed. The microscopic analysis has shown that the conditions dominant during the formation of this section were typical for swamp forest peats. New technologies also require expanding knowledge about the structure of coal seams. This is only possible with a detailed profiling of the coal seam on a macro scale combined with micro-profiling and a detailed petrographic description of the isolated lithotypes. This methodology is also useful in the facies analysis of bituminous coal seams.

Studies on the quality of bituminous coal are mainly focused on physico-chemical analysis, examining the ash content, sulphur content, volatile matter content, moisture content, and the Net Calorific Value of coal. Until now, the above mentioned parameters form the basis of the Polish Standard PN-82/87002, on the basis of which individual types of bituminous coal are determined. In addition, an elemental analysis, providing information about the content of primary elements in the organic matter of solids, i.e. coal, hydrogen, nitrogen, oxygen, and sulphur, is carried out for the selected samples. This issue has been studied by many authors, which undoubtedly provide invaluable knowledge due to the huge amount of data, but, as the authors themselves indicate, the knowledge of the petrography of coal, coking properties (Probierz et al. 2012) and finally the coke obtained from individual coal types (based on tests carried out using the Karbotest installation or the so-called „box tests” performed in the coke oven battery) is still very limited. The article discusses the impact of petrographic composition on the quality of metallurgical coke. The analysis was performed using samples of coking coal from the following mines: Pniówek, Zofiówka, Borynia, and Krupiński. The mentioned coal types are used to produce coke mixtures used for the production of coke in the Przyjaźń and Radlin coking plants. Based on the rank of coal and physicochemical parameters, the mentioned coal types were classified according to the Polish classification and the UN/ECE International Classification of In-Seam Coals (UN/ECE 1995). The prediction of thermomechanical properties of coke (CSR and CRI) performed according to the original CCP method were compared with the results obtained using the classical method of Nippon Steel Corporation.

Knowledge of the way in which minor and trace elements occur in coal is one of the most important geochemical indicators of coal quality. The differences between the methods of binding elements in coal in each coal seam and the variability of this feature of coal in the basin profile have not been discussed so far. These coal features were identified in a group of selected coal seams (209, 401, 405, 407, 501, 504, 510, 615, 620) in the Upper Silesian Coal Basin (USCB). At the same time, the differences in the role of identified mineral and maceral groups in concentrating specific elements in coal is highlighted. Identical or similar tendencies of changes in the way in which As and V, Ba and Rb, Co and Pb, Co and Zn, Mn and Pb, Pb and Zn, Co and Rb, and for Cr and Cu occur in the coal seams in the USCB profile was found. Changes in the mode of occurrence of As and Pb in coal in the USCB profile were probably influenced by carbonate mineralization. The changes in the mode of occurrence of Mni and Pb in the coal were probably determined by dia and epigenetic sulfide mineralization, while the content of Ba, Cr, Rb, Sr, and V in coal from these deposits was affected by clay minerals. It was observed that the greater the degree of the carbonization of the organic matter of coal, the lower the content of As, Mn and Pb in coal and the higher the content of Ba and Sr in coal.

Dependences Between Certain Petrographic, Geochemical and Technological Indicators of Coal Quality in the Limnic Series of the Upper Silesian Coal Basin (Uscb), Poland

This article aims to assess the values of the most often measured petrographic, geochemical and technological indicators of coal quality and to identify probable dependences between them in the USCB coal. The following can also be observed: high content of Cd and Co in carbonate minerals separated from coal, in clay minerals – Cr and Zn, and in sulfide minerals – Cu, Ni and Pb. Nevertheless, it is organic matter which has the greatest influence on the average content of trace elements in coal. Correlations between the values of some of the indicators of coal quality were also observed. It has been observed that the increase in vitrinite content in coal is accompanied by a decrease in, while an increase in the content of liptinite and inertinite in coal is accompanied by an increase in the content of CaO, MgO, and SO3 in coal ash. An increase in the carbonization of organic matter is accompanied by an increase in the content of Cu and Ni in coal, and a decrease in the content of Pb and S in coal and the content of Fe2O3 in coal ash.

Volatility is one of the most characteristic features in the all market types. In the raw material market, including the bituminous coal market, volatility is visible in the supply and demand variations, in consequence in the prices fluctuations. Market actors usually having opposite interests, for example buy low, sell high, are vitally interested in identifying the causes of these fluctuations.

Some of the factors causing the market fluctuations are quite common, others are more complicated because of circumstances complexity. This article attempts to examine the relationships between bituminous coal fines prices and the economic situation. Given the complexity of the issue, the research area has been narrowed down – territorially to Poland and temporarily – to the present decade.

The average prices of coal fines in Poland are presented by the Industrial Development Agency (Agencję Rozwoju Przemysłu SA) in the form of two indices: PSCMI 1 and PSCMI 2. Both indices are calculated based on the prices of pattern bituminous coal, produced by domestic manufacturers and sold on domestic markets, the energy and heat market respectively.

Statistical methods, because of their quantitative nature, are important in identifying the correlations between the coal fines prices and economic conditions. Therefore, the article presents examples of relatively strong linear correlations between the PSCMI 1 and/or PSCMI 2 and some indicators of the economic situation.