Breakthrough thickeners for iron ore project in Western Australia

Four 45 metre concentrate thickeners and four 90 metre diameter tailings thickeners fitted with a unique feed delivery system are set to assume a pivotal role in the processing circuits at CITIC Pacific Mining’s Sino Iron project near Port Headland, Western Australia.

The Sino Iron project is a large-scale magnetite iron ore mining and processing operation. Considered highly-technical and requiring significant processing and transport infrastructure, the project will, under full operating conditions, produce some 27 million tonnes of magnetite pellets and concentrate per year. This project also includes the single biggest order to date of Krebs pumps, cyclones and valves.

The eight thickeners, designed by FLSmidth Minerals, have been developed to accommodate the unique requirements of magnetite processing.

New technology within the feed system

The overall operational plan for the project includes

• two concentrate thickeners (delivering 72% solids)
• two high-rate tailings thickeners (64% solids) at the on-site processing plant
• two high-density tailings thickeners (72% solids) at the disposal site and
• two filtrate thickeners (delivering 72% solids) at the port processing facility, twenty-five kilometres away
• six primary cyclone manifolds and six secondary (regrind and tailings) cyclone manifolds utilizing gMAX technology and Technequip valves
• all centrifugal slurry pumps, 235 knife gate valves, all large ball valves, and a variety of other pumps throughout the plant.

The four tailings thickeners – each processing some 25,000 m3 per hour – include new technology in the feed system to maximise the mixing potential of the slurry and flocculant to deliver greater efficiency for output processing downstream.

High productivity and smaller footprint

Engineered for high productivity, the giant tailings thickeners are fitted with four rake arms and feature 4.5 metre high walls to aid compression. When fully operational, they will each process some 4,300 tph.

At both the mine site and the port facility, the concentrate thickeners have been elevated to meet site and environmental requirements. Elevated tanks provide safer working environment and improved maintenance and process outcome by eliminating the need for a tunnel improving access to the underflow pumps and associated equipment.