Mineable Lignite Reserves Estimation in Continuous Surface Mining

The deposit modelling and evaluation and the mineable reserves estimation of multi-seam lignite deposits is an essential process for mine planning activities. The first approach of the original drill holes data evaluation of the exploration programs refers to the analysis of the in-situ lignite seams characteristics. The algorithm of compositing of the drill holes assay intervals should take into account specific criteria of evaluation based on the corresponding power plant specifications as well as on the applied mining equipment. Especially in the case of continuous surface mining, the accuracy of the mineable reserves and the run-of-mine lignite quality estimation is a very important subject of mine planning and design procedure, provided that the applied equipment is less flexible to operation changes regarding the short-term scheduling. The objective of this paper is the investigation of the critical parameters which affect the lignite deposit evaluation procedure in relation to the algorithms of mineable reserves and run-of-mine lignite quality estimation in multi-seam continuous surface lignite mines. The analysis is based on a wide range of deposits, power plants and equipment parameters. Emphasis is placed on the spatial variability of the lignite deposit parameters and on the recommended design criteria as well as on mine development improvements.