4. COPPER CONCENTRATOR PROJECTS – HISTORICAL TIMELINE A number of Bechtel projects have been selected that cover developments over the last three decades in the Americas and Australia. This will allow one to highlight between remote south American projects in highly seismic areas versus projects in low seismic remote locations in the USA and Australia. Figure 30– Three decades of copper concentrator projects by Bechtel It should be noted that projects in South America have been developed at elevated altitudes above sea level and in some cases more than 300 km inland from the nearest commercial shipping ports. The supporting infrastructure of these projects requires much deeper analysis and nowadays with some geopolitical relationships (e.g. projects close to the ChileArgentina border). Figure 1 illustrates the range of projects delivered across the globe. 5. KEY INFLUENCING FACTORS IN THE DESIGN AND DEVELOPMENT PROCESS For a project to be successful, it requires an immense amount of work across all the study phases and into the project execution itself. From the earliest geological resource definition through early metallurgical testwork all the way through to variability studies and in some cases bulk sampling for pilot plant test work requires a huge attention to detail. As can be seen recently, the timeline from first discovery of the resource through to first metal can take around 15 to 25 years which is a significant timeline. In broad terms, below are some of the most influential factors to consider: • Site location • Resource definition and ore variability across the planned life of mine • Mineralogy, understanding of the ore that will be extracted over the life of mine • Metallurgical testing performance (Ore hardness and its variation, concentrate grade and recovery) • Understanding gangue mineralogy and potential minor elemental contaminants • Water requirements – supply and consumption, plus actual water chemistry of the water source • Power requirements – supply and consumption • Project location – geotechnical condition for construction of facilities • Impact of weather (particularly with respect to extreme temperatures, wind and snow / rainfall) • Transport and logistics associated with delivering materials, people and equipment to the project site • Process residue (tailings) – long term storage and water recovery / water reclaim • Operation and maintenance staff requirements and shift rosters. • Operation and maintenance staff availability • Degree of automation and remote operating centers During the design of the process facilities, the focus will need to be placed on minimizing capital intensity while maintaining reliability, availability and maintainability. This means that the operating and maintenance philosophies need to be defined / established as early as possible and then stress tested in the feasibility and execution stages via Reliability-Availability-Maintainability (RAM) modelling. The operating and maintenance plans will be tested with respect to equipment sparing and the impact this has on plant availability. Plant footprint is another key focus area as this serves to influence the amount of bulk earth works needed to establish the site prior to construction and quantities of the major commodities; by optimizing the footprint, it allows to minimize mass concrete requirements while not compromising the accessibility for maintenance and
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