McLanahan Hydrosizer® History Rooted in Minerals Processing
A lithium mine in Western Australia recently purchased a McLanahan Hydrosizer® for removing mica from its spodumene-bearing pegmatite ore.
For over 50 years, Hydrosizers® have provided the mining industry with nearly ideal-efficient classification by size as well as the capability to separate particles by specific gravity using a dense bed of teetered solids. In general, Hydrosizers® accept feed material into the top of the unit via a central feed well. Water is injected near the center of the unit to create an upward rising current, which soon establishes a zone of suspended solids. Smaller or less dense particles are lifted out of the Hydrosizer® and over the weir, while larger or denser particles pass through the current to be collected in the underflow cone for discharge.
McLanahan Hydrosizers® are based on the designs of the company’s legacy brand LPT Group, which has had Hydrosizers® operating in various minerals processing applications around the world for decades.
In one example of this, a customer making iron ore pellets required its iron ore concentrate to be less than 1% silica. Hydrosizers® were used to upgrade the conventional 5% silica concentrate to less than 1%. The overflow from the Hydrosizer® was again treated in other Hydrosizers™ to bring the concentrate back down to less than 5% silica for normal pellet grade.
Another minerals processing application in which Hydrosizers® are used is for preparing phosphate for flotation circuits. Flotation circuits typically can’t float out particles coarser than 0.5mm, so a number of phosphate operations use Hydrosizers® to make the 0.5mm separation. The coarser material that exits out the bottom of the Hydrosizer™ can be sent back to the grinding circuit or to tailings, depending on grade, while the fines that overflow the unit are sent to the flotation circuit.
These are just a few of the many mineral applications using Hydrosizers®. Others include the processing of tantalum, feldspar, garnet, silica, mineral sands, coal and many more.
Now part of McLanahan’s product line, Hydrosizers® continue to provide sharp wet classification for minerals processing applications. McLanahan has updated the design from square units to round, eliminating potential dead zones of material buildup in the corners. McLanahan has also added side-accessible teeter water pipes for easier, faster and safer maintenance of the water distribution system.
As with all of its equipment, McLanahan is able to tailor its standard designs to meet customers’ specific needs. For the spodumene project, McLanahan opted to provide ceramic ball valves in lieu of its more standard pinch and linear dart valves. These ceramic valves are ported for linear control and are expected to perform better than rubber-lined units for this duty. The valves also have special v-gates to prevent them from closing on a pebble of spodumene ore and destroying the ceramic valve.
Former Project Delivery Manager, now Director of Engineering Brent Gooley said one of biggest advantages of partnering with McLanahan on a project like this is the company’s vast experience working with a variety of materials. Coupled with local support and advanced control systems, McLanahan is able to pull from its global network of personnel and resources to deliver these advanced projects.