The advent of mine planning and scheduling computer software for underground mine design has greatly enhanced the planning process. Previously, mine planning was carried out by hand or with the assistance of standard CAD packages. Reserves were calculated manually using default values for relative density and seam thickness across large areas, and scheduling was done with manual calculations or via spreadsheets. The planning process was time consuming and did not readily facilitate the comparison of numerous iterations against each other. It focused heavily on production continuity and resource recovery, the degree of accuracy was often low, and at the end of the design process the understanding of the resource was still very limited.
But things have improved. The widespread acceptance of computer technology in our everyday lives has provided the platform for change, and the major issues that have reshaped and improved the whole mine design process and necessitated a higher level of confidence in mine planning have included:
* The increase in production capacity of the industry.
* The increased competition and product variety produced.
* The dramatic increase in capital expenditure required to establish a new mine.
* The need for ongoing customer satisfaction.
The current crop of underground mine design software suppliers in the Australian market are listed in the accompanying table. MINEX and XPAC currently have the strongest user bases in the underground sector of the Australian coal mining industry, in terms of both mine site personnel and external consultants.
Of the five underground design packages, MINEX, Vulcan and Minescape have been established for the longest period. These packages all contain geological modelling software, to which the underground design module is integrated. They all originated as UNIX-based programs, running on expensive workstations. They have since been configured to run under the Windows NT operating system. This change has reduced the total system cost dramatically, as a $3000 PC can now be used in place of the $20,000 workstation that was required as late as 1998.
The recently developed design packages, ICAMPS and XPAC, are based on the Windows environment.
The continued expansion of suppliers will probably be hindered by the ongoing consolidation occurring within the coal industry, evident by the spate of mergers and acquisitions of mining companies of the past few years. Imagine two mining companies with separate design packages. If the two companies became one, it is likely the software would be standardised across the board, and one design package would be discarded. The end result is larger slices of the market for fewer software suppliers. The considerable rationalisation activity that has taken place on the part of several of the software developers in recent times should prepare them well for any possible process of attrition of software suppliers that could follow from the industry consolidation.
XPAC has undergone substantial development, which has raised the bar in terms of overall functionality. The first consideration is the integration of a margin ranking facility, whereby geological and geotechnical data is analysed across the lease area to determine the most profitable mining areas, providing input into the optimisation of the financial performance of the project. Previously, this type of work could be undertaken in Excel, but required considerable time and effort to set up. XPAC has simplified the process markedly. Project financial performance is now an important consideration at the initial planning stages, and the mine planner can more readily assess the impacts of changes to the mine design.
The other advance in XPAC is the linking of the financial evaluation package XERAS to the production scheduling process, removing the need to generate reports, reformat them and import the data into a separate financial model. With the XPAC/XERAS combination, the financial implications of a change in mining parameters can be derived very quickly and easily.
MINEX is also undergoing significant change, with the creation of a totally new graphical user interface (GUI). Experienced MINEX users have generally considered MINEX to have the superior ‘back-end’ (the ability to arrive at the correct answers in the quickest possible time) compared to the other packages. But MINEX has also suffered from a very steep learning curve for users. The new GUI should go some way to remedying this situation.
*Graeme Rigg is a senior mining engineer with Minarco.
