Abstrakt: |
The efficient use of both the main and accompanying minerals is one of the fundamental problems of rational mineral resources management. The article presents the problems related to the documentation of limestone, one of the accompanying minerals in the Bełchatów lignite deposit (central Poland) used for the production of SO2 sorbents and desulfurization in the Bełchatów conventional power plant, which is located in the immediate proximity of the deposit. Both lignite resources and the annual production (over 42 million tons per year) put the Bełchatów mine among the largest European suppliers of this raw material. The Jurassic limestone occurs in the opencast slopes. They are gradually uncovered as a result lignite mining. In order to ensure the stability of slopes during the extraction of lignite, it is necessary to form them to the desired dip angle. This involves the need to extract up to 70 million tons of limestone. Limestones from Bełchatów deposit are characterized by a high lithological variability, numerous marl interbeddings and marl rocks, and various secondary mineralization processes. This results in a high variability of physico-chemical and physico-mechanical parameters forming the basis for the assessment of the suitability for numerous economic applications. A reliable geological documentation of limestone as a raw material for the production of SO2 sorbents requires a quantitative assessment of parameters and the development of a model of spatial distribution of their values, allowing determining batches meeting the required specifications. The documentation is difficult due the fact that the production of limestone, as an accompanying mineral, is limited due to technical requirements of the exploitation of the main mineral, and in particular by the need to separate minerals from gangue (mineral processing) in order to form excavation scarps. Due to the lower economic importance of the accompanying mineral, its degree of exploration, when compared to the main mineral, is low. In addition, it is characterized by a lower density of exploratory boreholes and significantly longer average lengths of samples collected from drill cores. This makes it practically impossible to construct a fully reliable 3D model of the distribution of limestone parameters, which is crucial for determining limestones that can be used for the production of sorbents. [ABSTRACT FROM AUTHOR] |