In 2014 a leading diversified natural resources company was considering the development of its bauxite deposit in Guinea, Africa.
The project which comprises a mine and associated infrastructure would produce and export 10 Mt/y of bauxite.
The company had previously completed study work on the project which considered conventional road and/or rail options as the means of delivering the product to the available port facility.
Ausenco was commissioned to conduct a concept study that considered an alternative approach to the transportation of the product to the port facility using a long-distance slurry pipeline, and to compare this approach with a more traditional rail transport method.
Ausenco developed a conceptual study and order of magnitude cost estimate to evaluate the technical and commercial feasibility for the proposed plant-to-ship concept, including the necessary infrastructure upstream and downstream of the long distance pipeline, the process plan and terminal/port facilities.From the bauxite process plant, the bauxite pipeline would transport the concentrate to the terminal and river port facilities located approximately 110 km away.
The pipeline system would comprise a buried 26-inch API5L-X42 bare steel pipe with a single pump station located near the process plant. The pipeline, including two intermediate valve stations, would be operated from the process plant main control room via a fibre optic communication system along the entire length of the pipeline.
At the pipeline terminal, the bauxite concentrate reports to desliming cyclones where approximately 4.6 Mt/y of fines (slimes) are separated and rejected to the tailings storage facility. The deslimed concentrate reports to a bank of three belt filters and is dewatered to a moisture limit suitable for safe shipping.
The scope of work included the following key elements for the slurry pipeline transport option:
The cost-effective processing, transport and shipping of fine bauxite using a long-distance slurry pipeline transport infrastructure would be a world first. Challenges associated with dewatering/drying fines and achieving a cost effective solution required a holistic plant-to-ship supply chain approach.
The proposed concept plant-to-ship infrastructure is deemed technically feasible. Value to the project and enhancement of capital and operation cost confidence level can be achieved from progressing engineering definition in the following areas:
The client is currently comparing the technical and commercial feasibility options available before determing the next steps.