Contribution on Lignite Recovery from Multi-Seam Deposits

Multi-seam lignite deposits consist of thin lignite seams alternating with thin sterile intercalations. This type of deposit requires selective excavation; however, thin sterile intercalations are unavoidably co-excavated with lignite, thus reducing the run-of-mine lignite quality. Criteria based on the lignite quality and the technical specifications of the equipment are used in order to evaluate the recoverable lignite. Both geological lignite recovery and geological lignite losses have to be determined in order to achieve efficient lignite exploitation. This article illustrates the method and the criteria of determining the lignite recovery in multi-seam lignite deposits of the Ptolemais basin, the biggest lignite deposit in northern Greece. Using this method, lignite recovery of up to 93.2% is achieved.