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MechChem Africa talks to Multotec Group CEO Thomas Holtz about establishing digital platforms for minerals processing plants and the need for much closer cooperation and collaboration between service and equipment suppliers, to realise the true value of 4IR-technology and autonomous processing.
“The journey towards the autonomous plant is not hugely different to the one for driverless vehicles, but before getting into that, I think we need to focus on the intent,” suggests Thomas Holtz, CEO of the Multotec Group.
“The idea of using technology to replace people, I believe, is the wrong mindset completely. At the outset, I think we must make a case for the human being in this equation. This notion that we can do minerals processing without humans doesn’t make any sense to me. Our equipment is often installed in remote areas surrounded by impoverished communities. Employment questions are therefore serious and we must question the role of the human in the digital 4IR environment,” Holtz argues.
The real challenge, he believes, is to see our organisations in ecological terms, with a head, heart and hands for thinking, feeling and doing. “Automated solutions may be able to think/analyse and do/respond faster and more consistently than a human can, but this discounts the human ability to feel empathy, connect with others and bring creativity and energy in response to changes being experienced. The value to human beings and the role they play in creating and using digital platforms needs to be highlighted at the starting point of this journey,” says Holtz, adding that the skills and know-how are already available to make the workplace more attractive for everyone. “We need to embrace this journey with the acknowledgment of where the human being fits in,” he say.
Africa and South Africa are sitting on plant assets that are relatively old, many plants being more than 30 years old, he continues. “We can’t retrofit these old plants completely. We need to start building new plants from the ground up, but we need to start with a different mindset. The idea that we can replace an operator with a robot is the wrong way of thinking. Instead, we need to take an overview of the process flowsheet in its entirety: how plant engineers design the system; and how the equipment suppliers deliver pieces of equipment that can work optimally and seamlessly together to deliver the results required,” he says.
“Core technologies involved in 4IR plants include data management, communication technology, and sensors that collect data and the analytics to make sense of the data and provide useful information from it. The ability to share information coming from each piece of plant equipment becomes essential, because the whole system is influenced by all the components feeding into it. Shared data then needs to be collectively compiled, analysed and displayed to be of use to plant operators,” he notes.
This approach signals the need for collaboration: “We need partnerships, alliances, a network infrastructure and like-minded people to deliver the initial plant and then to keep the plant operating optimally. This is contrary to our current business model, where each company has an R&D division to develop and test prototypes before patenting and commercialising begins, all while remaining in-house. In the new digital world with so many advanced technologies embedded into every aspect of a plant, this closed and confidential approach is surely going to be impossible.
“No company can do this on its own; all of the specialist equipment providers like ourselves will have to collaborate to make this possible,” Holtz tells MechChem Africa. “We need to be willing to form partnerships and alliances, share information and open up our businesses to a host of stakeholders, including competitors,” he says, adding that the package that ultimately runs an autonomous plant will, undoubtedly, be a collaborative one that uses shared information rather than copyrighted and protected IP.
Citing an example, Holtz says IMS has a Kawasaki crusher installed at a client site where Multotec has supplied screen panels and cyclones. “We are negotiating a shared platform to provide information from the screen panels that is useful for the crusher, and vice versa. We hope to start influencing the crusher efficiency based on the recirculating load we are picking up off the screen panel, for example. And we are already able to supply this data using vibration sensors on our panels. So our data can help make IMS’s Kawasaki crusher more efficient,” he explains.
“Through our involvement with SAMPEC, (South African Minerals Processing Equipment Cluster) we are trying to persuade our fellow equipment suppliers to identify more pilot collaborative projects that use common service providers for the communication, data and analytics technology. Ultimately, plant operators need to see the collective result, they can’t be expected to succeed by juggling separate pieces of information from different suppliers. The ultimate goal is a single platform that brings all the interacting components together based on how the whole plant is running.
“But this depends on collaboration between different equipment providers and OEMs and this vital step on the journey needs to start now,” Holtz believes.
Multotec started its 4IR journey a few years back with some R&D projects on separate pieces of equipment. “We now have sensors on our cyclones, screen panels and mill liners, and we have invested heavily in modelling and trending the data so that we are able to live stream data, analyse it and extract performance and efficiency information. When we started out, we were under the impression that we would have to develop our own sensors. We now know that a simple standard sensor such as vibration sensor can provide almost everything we need,”
he discloses.
Citing an example, he says Multotec cyclones are sealed units that typically run 24/7 on a plant. Refurbishment of these is based on the wear rates of the liner, but it is difficult to routinely check these liners. “So we set out to develop a way of monitoring the wear rate in real time to determine exactly when a replacement was needed. Initially, we looked at traditional thickness measurement tools: infrared, X-ray and ultrasound technologies. We soon realised that by putting a standard vibration sensor onto the outside of a cyclone we could easily pick up data about the vibration as a result of movement of material, and we could use this data to identify trends relating to liner thickness changes.
“Taking this further, we have partnered with an artificial intelligence (AI) company to develop machine learning algorithms based on the vibration data. It is amazing how much information we can pick up by fully analysing the data from this simple sensor,” Holtz tells MechChem Africa. “We can now pick up the presence of pieces of metal inside the cyclone (metal hang-up) and we can notify the client immediately. And with AI technology, we can create algorithms to look for a multitude of specific performance, wear and fault conditions,” he adds.
He says that Multotec is also using gyro sensors to track how a screen is flexing in all three axes. “The data we get is complex, but with AI, we can determine a huge amount, starting with throughput and the recirculating load and going all the way to misalignments, faulty springs or excitors and screen media damage – and we are achieving 80 to 90% correlation on wear monitoring,” he says.
The business side also needs to evolve, he continues. “The real benefits do not lie in condition based maintenance, although these are useful,” Holtz asserts, adding that this is already being implemented on several Multotec installed units. “The true value of the autonomous plant lies in production efficiency and optimisation: being able to extract the highest possible mineral recovery from the whole plant, from run-of-mine ore to saleable minerals.”
Minerals processing lines always have variability and, if a fully autonomously run plant is the objective, the whole plant needs to respond quickly and automatically to these changes. With cyclones, recovery efficiency is determined by the minimum and maximum battery limits: the feed volume and pressure, for example. “If, for any reason, feed parameters exceed the upper or lower limits, valuable resources will be lost. Operators, therefore, tend to target the centre point of the limit band, but using feedback from a digital platform, the set point can be set at its most efficient point near the top of the band, because the system can auto-adjust to prevent the upper limit being exceeded. This enables the whole plant to be run in a narrow window at the higher capacity,” Holtz points out.
“Collaboration is key, though,” he reiterates. “ We tend to like paddling our own canoes in South Africa, even when promoting localisation initiatives or lobbying for industry-wide government support. We need to be more prepared to align with each other, establish partnerships and share our IP with our fellow equipment providers.
“Tesla is the closest to having succeeded in developing the autonomous motor vehicle, but to deliver this innovative success story, an incredible collaborative ecosystem has been built consisting of multiple highly specialised partners. The autonomous minerals processing plant will need similar levels of collaboration. No one of us can do it on our own,” Holtz concludes.
