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Abstract

Applying new technologies basing on coal utilization demands precise identification of coal-bed composition. It is suggested, that such possibility is enabled by coal-bed logging with use of - adjusted to this aim - microlithotype analysis. Modification of this research method relies on ten-fold augmentation of 20 point grid size dimensions - up to 500 x 500 [...]. Maceral associations - as identified duringmicroscope observations - are placed in computer database according to their localization in logging. This allows for later graphic interpretation - microlithotype profile drawing. 13 associations has been educed in description, in majority being consistent with commonly used microlithotypes. However, a few changes has been introduced: in description of vitrite, telovitrite, macroscopically recognized in logging as vitrine layers, has been distinguished, as well as detro-gelo-vitrite, macroscopically recognized in logging as durain, while within bimaceralic microlithotypes there has been distinguished: vitrinertite (W), vitrinertite (I), clarite (W), clarite (I), durite (L), durite (I), all on the basis of dominant ingredient named in parenthesis. Accepted research methodology enables precise characteristics of petrographic variation within coal-bed logging. This allows especially to describe variation within dull coal (durain). Basing on research results, it is suggested that the biggest share in seam composition belongs to duroclarite - 23.8%, then vitrite - 18.7% and clarodurite - 17.6%, lower share of few percent belongs to: vitrinertite (I), vitrinertite (W), inertite, clarite (W), vitrinertoliptite, durite (I), durite (L), while both liptite and clarite (L) are less than one percent . Sequence of following microlithotypes also illustrate facies variation, what allows interpretation of environments of peat deposition in paleo-peat bog 116/2. Dominating percentage in log belongs to Forest Moor facies - 33.5%, while the lowest is Forest Terrestial Moor - 12.5%.

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Authors and Affiliations

Jacek Misiak
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Abstract

Proper values of physical and mechanical properties and their homogeneity are one of major requirements deciding about technological suitability of the rocks quarried to manufacturing aggregates. These properties depend on the natural features of a rock, its mineral composition, texture and structure. The characteristic of aggregates and the technical requirements they must meet are normalized in adequate standards that describe the procedures of conducting particular determinations and the methods of interpreting their results. In the basaltoids (usually called basalts) of selected deposits of Lower Silesia that represent different intrusive forms, five textural varieties have been distinguished: aphanitic, aphanitic-porphyritic, porphyritic-aphanitic, porphyritic-nodular and nodular-porphyritic. The petrography and essential physical and mechanical properties of these varieties have been described in Tables 1 and 2, respectively. The highest technical parameters have the aphanitic and aphanitic-porphyritic rock varieties. They result mainly from the textures of these rocks and their insignificant weathering, and to a lesser degree from their mineral composition. The resistance to wear (micro-Deval) and the resistance to fragmentation (Los Angeles) of the aggregates that represent the grain fraction 10-14 mm of the five varieties of basaltoids and the rock composites were determined according to the standards PN-EN 12620: 2008 and PN-EN 13043: 2004. Of the aggregates produced from the five major varieties, only those made of the nodular-porphyritic basaltoids have the properties of lower categories, whereas the remaining four are the materials of very high quality. Additionally, it has been shown that by combining various basaltoid types it is possible to produce composite aggregates with the variable qualities belonging to the categories LA and MDE (Tab. 3). The effect of rock petrography on the differentiation of the parameters of aggregates depending on the grain fraction of the products (Fig. 1, Tab. 4) is the lowest in the case of the aggregates produced from the homogenous and not weathered rock. In contrast, the range of variability of the parameters is higher if the starting material to produce aggregates is composed of several textural varieties and shows signs of weathering as well. The possibility of delineation of the areas occupied in the deposit by basaltoids with specific textural varieties creates the conditions of determining the rock zones, from which the aggregates of the predicted quality may be produced. This quality may be controlled and partly changed to the user needs by producing aggregates from the specially prepared rock mixtures (i.e. the charge to crushers) with specified proportions of the basaltoid varieties.

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Authors and Affiliations

Marek Rembiś
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Abstract

Wood pellets are classified as a solid biomass type. They are one of the most popular bio-heating fuels used in Europe, especially in the small heating sector, where pellets are burned in low-power domestic boilers. The pellets and automatic pellet-fired heating devices gained popularity due to the increasing air pollution (smog) problem and the low emission limiting campaigns associated with it. Wood pellets are formed as a result of small forestry particles mechanical compression (mainly conifers originated) and they are listed among renewable energy sources. The purpose of the presented studies was to compare the quality of wood pellets used for pellet-fired boilers and to identify, qualitatively and quantitatively, impurities marked in the samples obtained from the domestic market. The application of petrographic analyses, applied so far in relation to fossil fuels, is a presented work innovation for wood pellets. The microscopic analyses were performed on both certified (ENplus/DINplus) and uncertified wood pellets available on the market. Unfortunately, the analysis revealed that the quality requirements were not met, because of the unacceptable contamination presence. The unacceptable organic inclusions in the analyzed samples are fossil coals and their derivatives, coke, and polymeric materials of natural origin. Unacceptable inorganic inclusions determined in the analyzed samples were: glass, slag, rust, pieces of metal, stone powder, plastic, and polymeric materials of inorganic origin.

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Authors and Affiliations

Adam Nocoń
Iwona Jelonek
Marta Jach-Nocoń
Zbigniew Jelonek

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