It is well known that lignite satisfies over 70% of Greece’s needs in electric power. Out of the 60 million tons of coal produced annually in Greece, 48 million tons derive from the coal fields of northern Greece. In addition, by the year 2002 it is expected that another 2,5 millions tons of coal will be exploited from the coal fields of Florina in order to satisfy the newly under construction, 365 MW plant, located at Meliti, Florina, Northern Greece.

The scope of our presentation is to identify potential problems in the homogenization processes which someone might not realize if he restricts himself in looking only at the results obtained from the classical or rudimentary analysiw of coals. It is abundantly clear that Greek lignites appear in multilayer seams interrupted by interbedded sediments, and having substantial intercalations. Moreover, the length of the seams promotes or enhances variabilities in properties. As a result, one has to consider the impact of interbedded sediments in the process of homogenization. In the past, serious operational problems occurred at the Amynteon power station, northern Greece, due to the presence of unexpected minerals such as quartz, feldpars, and pyrites. These minerals caused the shut down of the power of the power plants thus costing PPC of Greece millions of dollars in damages and lost revenues though the nature of the combustible material, as obtained from the classical methods of analysis, was the same as the other power plants of Ptolemais, Kardia, and Aghios Dimitrios.