Pit optimisation is the earliest and most established application of its kind in the minerals industry, but this has been primarily driven by metal, not coal. Coal has the same financial drivers for resource optimisat...Pit optimisation is the earliest and most established application of its kind in the minerals industry, but this has been primarily driven by metal, not coal. Coal has the same financial drivers for resource optimisation as does the metalliferous industry, yet pit optimisation is not common practice. Why？ The following discussion presents the basics of pit optimisation as they relate to coal and illustrates how a technology developed for massive deposits is not suitable for thin, multi-seam deposits where mine planning is often driven more by product quality than by value drivers such as Net Present Value. An alternative methodology is presented that takes advantage of the data structure of bedded deposits to optimise resource recovery in terms of a production schedule that meets constraints on coal quality.展开更多
Among spatial interpolation techniques,geostatistics is generally preferred because it takes into account the spatial correlation between neighbouring observations in order to predict attribute values at unsampled loc...Among spatial interpolation techniques,geostatistics is generally preferred because it takes into account the spatial correlation between neighbouring observations in order to predict attribute values at unsampled locations.A doline of approximately 15 000 m 2 at 1 900 m above sea level (North Italy) was selected as the study area to estimate a digital elevation model (DEM) using geostatistics,to provide a realistic distribution of the errors and to demonstrate whether using widely available secondary data provided more accurate estimates of soil pH than those obtained by univariate kriging.Elevation was measured at 467 randomly distributed points that were converted into a regular DEM using ordinary kriging.Further,110 pits were located using spatial simulated annealing (SSA) method.The interpolation techniques were multi-linear regression analysis (MLR),ordinary kriging (OK),regression kriging (RK),kriging with external drift (KED) and multi-collocated ordinary cokriging (CKmc).A cross-validation test was used to assess the prediction performances of the different algorithms and then evaluate which methods performed best.RK and KED yielded better results than the more complex CKmc and OK.The choice of the most appropriate interpolation method accounting for redundant auxiliary information was strongly conditioned by site specific situations.展开更多
文摘Pit optimisation is the earliest and most established application of its kind in the minerals industry, but this has been primarily driven by metal, not coal. Coal has the same financial drivers for resource optimisation as does the metalliferous industry, yet pit optimisation is not common practice. Why？ The following discussion presents the basics of pit optimisation as they relate to coal and illustrates how a technology developed for massive deposits is not suitable for thin, multi-seam deposits where mine planning is often driven more by product quality than by value drivers such as Net Present Value. An alternative methodology is presented that takes advantage of the data structure of bedded deposits to optimise resource recovery in terms of a production schedule that meets constraints on coal quality.
文摘Among spatial interpolation techniques,geostatistics is generally preferred because it takes into account the spatial correlation between neighbouring observations in order to predict attribute values at unsampled locations.A doline of approximately 15 000 m 2 at 1 900 m above sea level (North Italy) was selected as the study area to estimate a digital elevation model (DEM) using geostatistics,to provide a realistic distribution of the errors and to demonstrate whether using widely available secondary data provided more accurate estimates of soil pH than those obtained by univariate kriging.Elevation was measured at 467 randomly distributed points that were converted into a regular DEM using ordinary kriging.Further,110 pits were located using spatial simulated annealing (SSA) method.The interpolation techniques were multi-linear regression analysis (MLR),ordinary kriging (OK),regression kriging (RK),kriging with external drift (KED) and multi-collocated ordinary cokriging (CKmc).A cross-validation test was used to assess the prediction performances of the different algorithms and then evaluate which methods performed best.RK and KED yielded better results than the more complex CKmc and OK.The choice of the most appropriate interpolation method accounting for redundant auxiliary information was strongly conditioned by site specific situations.
