National Metrology Institute of SA
The RAM5 is a patented, modern, industrial mixing technology, capable of mixing quantities varying from 1 to 36 kg.
The National Metrology Institute of SA unveiled its state-of-the-art production-scale Resodyn Acoustic Mixer, better known as RAM, in April 2017.

The National Metrology Institute of SA’s  facility is located on the Council for Scientific and Industrial Research campus in Pretoria, South Africa.

Mining Review Africa’s senior deputy editor, Chantelle Kotze.

Chantelle Kotze reports.

The National Metrology Institute of SA acquired the production-scale RAM5 unit at a cost of R12 million to enable it to mix larger quantities of material, a feat not previously possible.

To complement this, the National Metrology Institute of SA will also be procuring a bench top, laboratory-scale RAM2 unit – which is used for small scale research and testing.

“This enables us to not only provide these services to industry, without them having to incur the cost of acquiring the technology; but also enables us to improve our service offering and fulfil our mandate as a metrology institute,” says National Metrology Institute of SA CEO, Ndwakhulu Mukhufhi.

The RAM5 is a patented, modern, industrial mixing technology, capable of mixing quantities varying from 1 to 36 kg, that thoroughly mixes gases, liquids, solids, powders and very viscous materials, without the need for impellers or agitators.

“The mixer works similar to that of a paint shaker, yet shakes much faster and harder than a conventional paint shaker, explains US-based research and development firm Resodyn senior electric and controls engineer, Brian Seaholm.

“The RAM process uses low-frequency, high-intensity acoustic energy to create a consistent shear field throughout the entire mixing vessel that in turn ensures complete and thorough mixing of several different elements, either solid-solid; liquid-liquid, liquid-solid and liquid-gas.

[quote]It does this by vibrating up and down at 60 cycles a second at 100 g of acceleration and at a displacement of 14 mm,” he explains.

Seaholm adds that an automated hoist safely loads vessels into the mixer. Digital controls and sophisticated software provide real-time monitoring and control of the mixing process.

The benefits of using a RAM5 includes faster cycle times, reduced process waste, simple scale up, flexibility in mixing vessel selection, and new options for product and process design.

Specific examples from the energetics, abrasives and dentistry industry sectors were presented that demonstrate a 57-95% reduction in ingredient addition and mix cycle times. In the energetics examples this resulted in 66% greater production volumes and 50% less waste generated.

Mukhufhi said at the event that the National Metrology Institute of SA is the first institution on the African, South American, and Asian continents to own a production-scale RAM5 acoustic mixing system.

“This technology reinforces the National Metrology Institute of SA as a thought leader and an industry go-to for these kinds of expertise because we are the only owner of a production scale unit which means that the potential impact of this within South Africa is significant.

“Investigations have demonstrated significantly improved material mixing, and reduced mixing-time compared to traditional mixers. Over eight Fortune 500 companies in the world own the RAM5 technology, with all intellectual property rights protected as it provides distinct competitive advantage over other material producers.

“The RAM technology could benefit most industries in South Africa, most specifically the mining, pharmaceuticals and manufacturing sectors,” states Mukhufi.

He explained that this mixing technology is essential for South Africa as it assists in helping these sectors remain competitive.

“Most of the products that are manufactured or produced for different applications require homogeneity in the product; every part needs to be the same, and that is what the technology does,” he notes.

The National Metrology Institute of SA plans to make the mixing technology available to all potential users in all manufacturing spheres in the hopes that clients would engage with the institution and co-develop their required materials, and perhaps some novel materials, in partnership with us,” says Mukhufhi.

Supplementary service offering

In support of this new technology available at the National Metrology Institute of SA, measurements such as nanoscale scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction can also be performed by the materials characterisation section within the institute.

The materials characterisation team will assist with the characterisation of these novel materials to determine the intrinsic and procedural properties of materials, including compositional and micro-structural properties once mixed on the acoustic system, be it cosmetics, energetics (explosives), pharmaceuticals, polymers, ceramics or nanomaterials.

The National Metrology Institute of SA’s mandate

The National Metrology Institute of SA is responsible for maintaining the SI measurement units and to maintain and develop primary scientific standards of physical quantities for South Africa and compare those standards with other national standards to ensure global measurement equivalence.

It must also provide reference analysis in the case of a measurement dispute and maintain and develop primary methods for chemical analysis to certify reference materials for South Africa and the region.​​​​​​​​​​​​​​​​

The National Metrology Institute of SA also acts at the interface between the national and international measurement systems while also playing a leading role in the development of metrology infrastructure in Africa, especially in support of South Africa’s immediate neighbours, in SADC.


Feature image credit: The National Metrology Institute of South Africa

The benchtop, laboratory-scale labRAM units –  used for small scale research and testing.