Technology differentiation

Mineral processing equipment and solutions provider Multotec will focus on the parallel development of new innovations to existing mineral processing technology to complement its approach of focusing on innovation and verification in technology management. 

These developments – pursued in collaboration with tertiary institutions at the testing facilities of the Multotec Technology Division, in Johannesburg – included an adjustable spiral and a magnetic cyclone and water treatment and metals recovery technology, said Multotec Process Equipment technology manager Faan Bornman at a media briefing in Johannesburg last month. 

The application of a positron emission particle tracking rig is also being investigated to track particles in the cyclone and monitor mineral separation.

Key Developments

A PhD study is currently being undertaken under the leadership of the University of Pretoria on an adjustable or flexible spiral. The aim is to study the effect of varying trough angles and pitch lengths on the performance of the spiral.

“Multotec believes that the current spirals, which  have a  fixed trough angle, should rather include a varying profile, since some of the concentrate is removed at an early stage, thereby changing the characteristics of the material put through the spiral,” said Bornman, who oversees the research and testing 

He emphasized that the knowledge generated from these studies might be invaluable for future processing equipment designs.

The magnetic cyclone – to be used in coal and iron - ore applications – is being developed in collaboration with  North -West University.  The aim of the research is to improve the separation efficiency of the near dense material and ensure reduced misplacement in dense-media separation by magnetically controlling the differential over the cyclone. 

The use of non-magnetic material for the cyclone assembly and support to avoid disturbing the magnetic field, as well as the position and strength of the magnet, will be taken into account during the design research and testing.

Multotec aims to display the cyclone at the Electra Mining Africa Exhibition in Johannesburg later this year. 

The technology division’s testing facilities include a continuous ionic filtration (CIF) test rig, comprising a dual-stage CIF system, called DeSALx. The DeSALx desalination process uses two stages of CIF to desalinate brackish water to produce water with low dissolved solids content and a neutral pH.

A cationic resin is used in the first stage to remove cations, such as calcium and magnesium, from the water, while an anionic resin is used in the second stage to remove anions, such as sulphates and nitrates, from the water.  

The automated test rig has the capacity to treat water at a flow rate of 1 m³/h, yielding water recoveries of 90% and higher, depending on the feed water quality. The rig is fully mobile and can be relocated to customer sites for pilot work.

Multotec’s testing and verification facilities also include a sample de-sliming station, where fine material, smaller than -45 μ, is removed from the cyclone feed material. The technology division plans to implement a new de-sliming station by the end of this year.

“The aim is to improve the de-sliming process to be simpler, safer, less labour - intensive and process larger volumes of material – up to four times the original quantity,” said Bornman, who added that these improvements would also provide an increased test turnaround time for clients.

Multotec Process Equipment MD Rikus Immink noted that the innovations and testing services were ways through which Multotec could differentiate and add value to its products.

“Innovation starts with an idea . . . followed by an inward turning spiral of research, design, manufacturing, pilot testing, prototyping, installation, modification and repetition of the process until commercialisation . . . during this process, testing plays a vital role,” he concluded.

Published by Mining Weekly