Systematic Analysis of Energy Coal Mixtures in Judicial Practice. Case Study: Jiu Valley, Hunedoara County, Romania

There are several situations in which it is necessary to clarify the types of coal that enter into the composition of mixtures: technical expertise and/or establishing the nature of some coal wastes, often from old stockpiles, in order to eliminate them. The proposed method is based on the identification and description of those mineralogical-petrographic and physico-chemical properties whose pursuit can lead to a diagnosis in differentiation of coal types. Systematic analysis involves in the first stage the identification of the different types of coal present in the sample by mineralogical analysis. From the sample subjected to mineralogical analysis, granules are extracted from the different types of coal present in the sample and the characteristics defining them are determined: moisture and hygroscopic moisture content, volatile matter content, fixed carbon content, agglutination characteristics, etc. Further, the characteristics of the mixtures are determined on another part of the sample and their structure is determined by algebraic methods. There are situations when is necessary an evaluation of the quantity of material existing in a stockpile or possible to be stored in a dump. This could be done using CAD software for modeling the stockpile surface (upper surface) and of the terrain beneath the stockpile (lower surface) then a volume calculation can be made between upper surface and lower surface, confined by the boundary of the stockpile.