1. Mitigating Risk in the Mining Sector: Best Practice Implementation & Independent Audits
Jean Richardson, Andre McKen, Russ Calow, SGS Minerals Services
Outi Maatta, SGS Systems, Standards and Certifications
Adrian Shaw, SGS Project Finance

2. Definition of Risk, Risk Management
Risk - the effect of uncertainty on objectives
Risk management
identification, assessment, and prioritization of risks
followed by coordinated and economical application of resources
to minimize, monitor & control probability and/or impact of unfortunate events
to maximize the realization of opportunities
ISO 31000, Nov 2009

3. Risk in the Minerals Sector
PROJECT FINANCE
SSC

4. Top Risks to Mitigate, 2009/2010 Cost containment
Industry consolidation
Access to capital
Keep social license to operate
Climate change
Skills shortage
Lack of infrastructure access
Access to secure energy
Resources nationalization
Pipeline shrinkage
Technical/operational
Strategic
Financial
Social
Environmental
Operational/Human Resources
Location
Location/Operational
Political
Ernst and Young, 2009.

5. 54% Somewhat or extremely concerned
CEOs’ Concerns, 2009/2010
2010
2009
54% Somewhat or extremely concerned
Pricewaterhousecoopers, 2010

6. Energy Use
85%
14% 1%
3-4% of global energy consumption used for comminution. Of this 1% is used for grain size reduction.
Alavadro et al 1998
South Africa (Eskom) generates 38 GV/yr
AngloPlats uses 1 GV/yr
40% in comminution and smelting
Less than 1% results in grain size reduction
Countries heavily dependent on coal to generate electricity.
Rule 2009

7. Comminution Update Technology advancements
Jaw, cone crushers → ball& rod mills → SAG & FAG mills → HPGR
Complex deposits, complex mineralogy, fine grained ore
Finer grinding needed – UFG, Activox, multiple regrinds
1998 High Definition Mineralogy
2000 Variability in hardness & grindability - geometallurgy
Simulation and modeling in feasibility
Process and systems control
Technical and management audits
Plant improvements & ISO 50001
Need, costs and availability of power
Carbon emissions
1995 Escondita 34 foot mill – 13.4 MW power
34 foot mill – 9.3 MW power
2003 Chatree MW
2005 Collahuasi 39 foot MW
2001 Cadia foot MW (Newcrest)
Optimize flowsheet to be energy efficient:
a) exploit the mineralogy of the ore. Even within one deposit, various zones or domains have differenign graindability. Eg. Merenshy Reef vs UG 2 : Average energy requirement to smelt
Platreef: 579
Merenshy reef 554
UG2 667 b)

8. Technology Advances Replace old equipment & assess technologies
Design flowsheet for mineralogy – can require fine grinding
HPGR more energy efficient
40%
Reasons for the increasing popularity of HPGR technology include increases in energy efficiency within the comminution circuits, increased throughput in milling and processing and improvements in metallurgical efficiency.
These improvements can be attributed to the unique breakage patterns associated with inter-particle crushing and the production of micro cracks in rock particles. The applicability of HPGR technology within a flowsheet is ore dependent and so requires testing to estimate the size of equipment required and the effect on throughput and metallurgical performance associated with its use.
SGS Mineral Services offers a standardized laboratory scale test of high pressure grinding rolls and complements the test with the most extensive background in HPGR lab testing in the business. Proprietary models, a broad database and a depth of experience in data interpretation ensure that risk is minimized during investigations with this still-developing technology.
The product generated by HPGR is also often finer than products from conventional grinding circuits, leading to increased throughput through the comminution circuit as a whole.
An exciting application for HPGR makes use of the report of observed micro cracks within the rock particles themselves. Increased overall leach recovery or kinetics have been attributed to the formation of these fissures during crushing, and the subsequent contact of leach solution and fresh mineral surface. The boundaries of this new application for HPGR are still being explored and continue to produce new avenues for investigation.
20%
coarse
fine
Rule et al., 2009

9. Complex Deposits Mapping Variability/Geometallurgy
SGS SPI Grindability Test
Tumbling (abrasive) test
2 kg of 22 mm top size
Good for variability mapping
Batch test
Yields SPI & Ci for SAG design
Hardness
Domains

10. SGS SPI Database
soft
hard

11. Simulate & Populate the Block Model
SAG
MILL
BALL
MILL
Comminution Economic Evaluation Tool
Comminution Model SGS CEET
Completed

12. Throughput Modeled in 3D
5000
4500
Peruvian Porphyry Cu-Au
Blue / soft ore/ high tph
Brown / hard ore/ low tph

13. Predict Power Needs by Year (SAG and Ball Mills)
SAG MILL
P80
hard
Bulled, 2007a, b

14. Technical Audits Technical Audits (Plant optimization)
Surveys, sampling, analysis, troubleshooting
Many plant parameters
PSA, critical size build-up, mill speed, pulp density

15. Results Oriented: Improved Profitability
Cu plant
Implementation of a pre-crusher improved power efficiency 31% for hard ores
Capex = $US 11M
New revenues $US 40M/yr
Au oxide plant
Optimization increased throughput by 9.5% at similar grind
No CAPEX
New revenue $US13M/yr
Guidelines for Presentation: (left)
In this case, the plant was encountering occasionally a harder ore, which decreased their throughput significantly. A simulation study was carried on to determine the effect that would have pre-crushing for this particular ore. The simulation study yielded to a ‘go ahead’ for the project.
The installation of the crusher did cost $US11M, but the additional revenue from the additional throughput more than compensate for the investment.
Guidelines for Presentation (Right)
This is another example where plant optimization through computer simulation can increase profitability substantially, sometimes with zero capital expenditure. In this case, modification in operation allow for an throughput increase of 9.5%, which yielded in additional revenue

16. Management Audits: ISO Standards
BS EN → ISO
Energy supply and use including equipment and systems
Procurement and use-related disposal issues
Continuous improvement cycles
ANSI/MSE

17. Value of Systematic Energy Management
PRODUCTION
Decreased energy use
Controlled energy costs
Improved operational efficiency
PLANNING
Data for fact-based decisions
Operating and capital spending
Purchasing strategies
PROTECTION
Protection against energy market instabilities
Reduced environmental impacts, show corporate social responsibility
Competitive advantages

18. SGS: a Partner in Risk Mitigation