Compañía Minera Teck Quebrada Blanca’s pipeline system is designed to transport copper concentrate from the concentrator to the Punta Patache Norte port facilities area. The system includes a copper concentrate pipeline, make-up and reclaim water system, and tailings transport system.
Ausenco was selected to perform a pre-feasibility study update in Phase 1 of the project and a cost-saving engineering feasibility study in Phase 2.
In Phase 1, the client initially requested that we perform updates on the concentrate and seawater pipeline designs associated with a 41.6 million tonnes per year (mt/y) copper ore process. Subsequently, the client requested that we perform another update with a new design basis relating to an expanded plant capacity of 46.8 mt/y.
In addition, we performed three value engineering studies as follows:
- Optimal internal/external liner design for the seawater pipeline
- Trade-off study to determine whether the seawater pipeline should be installed above or below ground
- Trade-off study to determine whether the seawater pipeline should be installed next to the concentrate pipeline or in a separate right-of-way (ROW)
The CAPEX and OPEX estimates (+25%/-20%) were also updated to reflect the new design.
The concentrate pipeline system design included a 172 kilometre (km), 6.625/7.625-inch, HDPE lined concentrate pipeline with the capacity to transport 0.9 - 1.2 mt/y of copper concentrate. The system also included one head pump station, three intermediate valve/choke stations, four pressure monitoring stations and a terminal station.
The seawater pipeline system included a 172km, 42-inch, HDPE lined pipeline. The design also featured five pump stations with a maximum flow rate of 1 593 l/s (5 735 m3/h), and submerged intake with sump and vertical turbine pumps. The proposed pipelines were to be buried underground sharing the same right of way. The SCADA system utilised a common fiber optic cable buried in the trench with the pipelines. The study was completed in 2010.
The second phase of the project involved the design of a new copper concentrate transportation system, tailings system, make-up water pipeline and reclaim water system for processing 46.8 mt/y (135 000 tonnes per day) of hypogene ore in a new concentrator.
Ausenco executed a feasibility study in this phase for the following:
- 0.9 - 1.2 mt/y, 160km, 7-inch copper concentrate slurry pipeline from the Phase II concentrator to the port with one pump station, two choke stations, 2 valve stations, two pressure monitoring stations and an automated control system with leak detection
- 5 735 m3/h, 160km, 36-inch unlined desalinated water (make-up water) pipeline from a desalination facility at the port to process water ponds at the concentrator. System included five pump stations and an automated control system.
- 60km, 24-inch reclaim water pipeline system from the tailings dam to the concentrator with three pump stations
- 50km tailings transportation system from concentrator to the tailings management facility with open channel, rapids and collection boxes to dissipate energy generated by the 2 220 metre drop in elevation
A key achievement in this project included improving the prospective financial outcomes of the project by developing a route for the tailings pipelines which eliminated the low points and reduced the need for a high volume – and high cost – pumping station.
Our scope of work included:
- Route selection
- CAPEX (-10%/+15%)
- Trade-off study to determine whether the water system should be open or closed
- Trade-off study to determine whether the water pipeline should be lined or unlined
- Trade-off study to determine the optimal tailings transport system: pressurised pipelines or concrete open channel
Concurrently, Ausenco executed a feasibility study for intermediate storage, port load-out facilities and the seawater intake system at Iquique, Chile.
Our work on Phase 2 of the project was completed in 2012.