Breakthrough technology in thickeners for CITIC Pacific

The first of its kind in 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.
The eight thickeners, designed by solids/liquid separation specialists FLSmidth Minerals, have been developed to accommodate the unique requirements of magnetite processing. Additionally, the four tailings thickeners are introducing a new feed delivery system which will enhance mixing and markedly improve the quality of output.
The design and delivery of the eight thickeners is a joint venture between FLSmidth offices in Australia and China. The company’s WA office will supply the drive, lift and hydraulics for each cell with the mechanism, bridge and feed system coming from China.
The overall operational plan for the project includes two concentrate thickeners (delivering 72 per cent solids) and two high-rate tailings thickeners (64 per cent solids) at the on-site processing plant, two high-density tailings thickeners (72 per cent solids) at the disposal site and, at the port processing facility, twenty-five kilometres away, two more concentrate thickeners (delivering 72 per cent solids).
The four 90m diameter tailings thickeners – each processing some 25,000m3 per hour – will be equal to the largest diameter thickeners ever built in Australia. They are based on the proven FLSmidth thickener and E-Duc® feed system but 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.
Developed by FLSmidth design engineers in Australia following extensive CFD modelling of low aspect ratio feed wells by the CSIRO, the revolutionary feed system ‘barrel rolls’ the combined slurry/floc feed as it is introduced into the thickener tank to enhance mixing and retention in the feed well.
Engineered for high productivity, the giant tailings thickeners are fitted with four rake arms and feature 4.5m 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. Apart from a considerably smaller footprint than tanks of a similar size installed at ground level, elevated tanks will improve access to the underflow pumps and associated equipment. With a ground level tank, such equipment would be housed in and accessed through a series of tunnels and trenches.
These ‘bridge’ type concentrate thickeners are fitted with industry-proven EIMCO gearboxes and the bridge structures have been designed to accommodate a range of extra services including lighting and pipework.

For further information contact David Williams on tel: +61 (0)2 4320 4700 or email: david.williams@flsmidth.com