APPLICATION OF MATHEMATICAL PROGRAMMING MODELS TO COAL QUALITY CONTROL

The problem of utilizing blending techniques to control coal quality at the production-consumption phase is considered. Three blending models were developed to provide coal of high thermal content and low pollutants. With the aid of operational mine planning, coal is blended at the coal producing mines such that the best quality of coal is mined during a planning period, while meeting the management production objectives. The first model developed uses 0-1 programming formulation to select potential working areas of a mine on the basis of predicted grade values obtainable from geostatistics. A second model developed combines economically coals produced by different suppliers to meet the specification of a power plant. The second model uses a linear programming formulation to develop coal purchasing strategy. Finally, a multiobjective programming technique is used to determine the tonnages of coal which must be cleaned from various sources (e.g. stockpiles) in order to result in clean coal of high thermal content and low sulfur content. The two objectives used are minimization of total sulfur and maximization of total Btu.;Both the operational mine planning and coal purchasing models were tested on actual mine data. The study demonstrated the capability of controlling coal quality by blending technique with the aid of the three models. This can be translated into dollar savings to both the coal producer and the coal consumer.