Design and construction of surface air cooling and refrigeration installations

1. Ross Wilson* & Andre Pieters+ * BBE Projects + Impala Platinum Design and construction of surface air cooling and refrigeration installations

2. Description of refrigeration plant Aspects of construction management Lessons learnt Photographs of other large installations

3. Impala 16 Shaft Production 257 ktons / month Max depth 1 535 m VRT 57 °C Current maximum duty 31.5 MW (R)

4. Surface BAC and refrigeration systems TO SHAFT AMBIENT AIR BAC CHILLER[S] CCT

5. Obuasi Ghana KMS and GCS Shafts

6. Sprays Fans Water chillers Condenser cooling towers Continue

7. Return

8. Return

9. Return

10. Return

12. Construction management • EPCM • Turnkey

13. Construction project EPCM Option Turnkey Option • Partial EPCM • Client places orders • Client manages site Full EPCM Design & Build Design, Build & Operate Variations of EPCM Variations of Turnkey RISK Client High Turnkey Contractor High

14. Schedule EPCM Concept or pre-feasibility Feasibility study CBE study [detailed design & costing] Project Implementation

15. Schedule EPCM Concept or pre-feasibility Feasibility study CBE study [detailed design & costing] Project Implementation TURNKEY Concept or pre-feasibility Feasibility study Time Saving Tender and contract Project Implementation

16. Detailed design and client approval Civil works Manufacture of equipment Mechanical installation Electrical and instrumentation Commissioning Implementation - the real schedule Detailed design and client approval Civil works Manufacture of equipment Mechanical installation Electrical and instrumentation Commissioning

17. SAFETY • Mindset • Training • Induction • Communication • Task Observations • Risk Management • Risk Assessment • Risk Controls • Inspections • 4 Corrective actions • Review • Incident Investigations • Accident/Incident Review • SHEMS Review • Performance Review • Control Systems • Policy, standards, procedures. • Contractor Control • Incident monitoring • Document control

21. Conclusions • With Turnkey projects, risk shifts to contracting company • Whether Turnkey or EPCM mining company retains ultimate control over design aspects, sub-contractors, risk assessments, etc • With many mines in the USA approaching the threshold where refrigeration is required, the experience of the many South African mines who have installed refrigeration plants can be called on

22. From concept…… Amandelbult No.2 Shaft

23. ..… to completion Amandelbult No.2 Shaft

24. Impala No.11C Shaft, 13 MW Impala No.14B Shaft, 14 MW

25. Impala No.11C Shaft, 13 MW Impala No.14B Shaft, 14 MW

26. Obuasi Ghana KMS and GCS Shafts

33. Mponeng DSM Project