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Two key facts often stand out in relation to today's industrial processes: they are becoming increasingly complex, and there are fewer people available who have the skills and dedication needed to get the best out of them. Little wonder, then, that the traditional rule-of-thumb approach to process operations is steadily being replaced by control systems that can be fine-tuned to optimize them in terms of a variety of parameters, either singly or in unison. Technology has moved on dramati- cally since the first programmable logic control (PLC) systems became available in the early 1970s. As Martin Knabenhans, head of pro- cess control engineering at ABB, told Coal Age, the early PLC systems bear little resemblance to those available today. "There is a large range of automation lev- els, from the basic ability to monitor and interact with specific components (such as valves, pumps or motors) to complete process optimization systems, where the automation system takes over control of the process like an 'autopilot,'" he said. "One can safely assume that a highly automated system will provide a 20% improvement in productivity, product quality and energy efficiency, compared to a purely manual operation." As Knabenhans inferred there, there is a whole raft of componentry that can be applied in whole or in part to the indus- trial processes involved in mining and mineral processing — not forgetting, of course, that control systems are increas- ingly finding their way into the under- ground environment for applications such as ventilation and pumping. Rapid Development History Numerous advances have taken place in plant control and instrumentation technology over the past 10 years. "Ten years ago, control systems were not as open, integrated and object-orientated as today," Knabenhans explained. "Many solutions were either PLC + HMI (human-machine interface)-based with lots of effort for interface engineering between them, or proprietary — often closed — DC (distributed control) sys- tems. Alarm and asset management, historian and advanced process control, nowadays seamlessly integrated parts of modern automation platforms, could only be implemented by adding sepa- rate systems running on dedicated hardware and requiring different engi- neering environments. "The introduction of standardized wired and wireless, vendor-independent communication protocols connecting intelligent electrical and instrumentation devices to the automation platform has been another game changer," he added. Chris Culph, electrical engineer at Gekko Systems, noted that user-friendly interfacing, distributed components and data storage have been pivotal in gather- ing the required information from around process plants. "Historically, instrumentation had a feeling of a 'black art,' which often meant that devices were difficult to install, calibrate, and get con- nected into the control system," he pointed out. "Centralized systems also meant that required power and control cabling had to be run over large dis- tances at great labor and capital expense. The time and cost expense to get more information has become the key factor as to whether or not that information was absolutely necessary. "By suppliers making instruments easier to connect to, and providing some universal or commonality of communica- tions, and distributing data capture loca- tions (such as field-based PLC input and outputs), much of the cost has been reduced. This allows for further instru- mentation to be installed," Culph said. He also noted that over the past 10 years, data storage has increasingly become cheaper, so more information can be retained, pro- cessed and developed to provide better clarity on how a plant is performing. According to Bob Jonas, mining and metals market development manager at Honeywell Process Solutions, multivari- able predictive control (MPC) has had a considerable impact on directly improv- ing operations and delivering significant financial benefits. Honeywell now has more than 300 individual mineral pro- cessing units that are being optimized by its MPC, he said, with the technology being used in 20 different mineral pro- automat e d c o n t r o ls B Y S I M O N W A L K E R , E U R O P E A N E D I T O R 36 www.coalage.com December 2014 Smart Control Optimizes Operations In concentrators and mines alike, control systems are increasingly proving their worth as operators strive to streamline functions and improve productivity State-of-the-art control stations are designed for optimum usability. (Photo courtesy of Honeywell)